81 results on '"M Z, Hussain"'
Search Results
2. Uncertainty in phosphorus fluxes and budgets across the U.S. long‐term agroecosystem research network
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P. Welikhe, M. R. Williams, K. King, J. Bos, M. Akland, C. Baffaut, E. G. Beck, A. Bierer, D. D Bosch, E. S. Brooks, A. R. Buda, M. Cavigelli, J. Faulkner, G. W. Feyereisen, A. Fortuna, J. Gamble, B. R. Hanrahan, M. Z. Hussain, J. L. Kovar, B. Lee, A. B. Leytem, M. A. Liebig, D. Line, M. L. Macrae, T. B. Moorman, D. Moriasi, R. Mumbi, N. Nelson, A. Ortega‐Pieck, D. Osmond, C. Penn, O. Pisani, M.L. Reba, D. R. Smith, J. Unrine, P. Webb, K. E. White, H. Wilson, and L. M. Witthaus
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Environmental Engineering ,Management, Monitoring, Policy and Law ,Pollution ,Waste Management and Disposal ,Water Science and Technology - Published
- 2023
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3. Phosphorus availability and leaching losses in annual and perennial cropping systems in an upper US Midwest landscape
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Stephen K. Hamilton, G. Philip Robertson, M. Z. Hussain, and Bruno Basso
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Multidisciplinary ,biology ,Science ,Miscanthus ,Biogeochemistry ,biology.organism_classification ,Article ,Environmental sciences ,Agronomy ,Soil water ,Panicum virgatum ,Environmental science ,Medicine ,Miscanthus giganteus ,Leaching (agriculture) ,Cropping system ,Hydrology ,Eutrophication ,Surface runoff - Abstract
Excessive phosphorus (P) applications to croplands can contribute to eutrophication of surface waters through surface runoff and subsurface (leaching) losses. We analyzed leaching losses of total dissolved P (TDP) from no-till corn, hybrid poplar (Populus nigra X P. maximowiczii), switchgrass (Panicum virgatum), miscanthus (Miscanthus giganteus), native grasses, and restored prairie, all planted in 2008 on former cropland in Michigan, USA. All crops except corn (13 kg P ha−1 year−1) were grown without P fertilization. Biomass was harvested at the end of each growing season except for poplar. Soil water at 1.2 m depth was sampled weekly to biweekly for TDP determination during March–November 2009–2016 using tension lysimeters. Soil test P (0–25 cm depth) was measured every autumn. Soil water TDP concentrations were usually below levels where eutrophication of surface waters is frequently observed (> 0.02 mg L−1) but often higher than in deep groundwater or nearby streams and lakes. Rates of P leaching, estimated from measured concentrations and modeled drainage, did not differ statistically among cropping systems across years; 7-year cropping system means ranged from 0.035 to 0.072 kg P ha−1 year−1 with large interannual variation. Leached P was positively related to STP, which decreased over the 7 years in all systems. These results indicate that both P-fertilized and unfertilized cropping systems may leach legacy P from past cropland management.
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- 2021
4. Evaluation of Early Renal Involvement in Essential Hypertension by Measuring Urinary Biomarkers
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M R, Morshed, I, Ashraf, M Z, Hussain, T A, Khan, M I, Anwar, M N, Imtiaz, M A, Alam, N A, Siddiqui, and A S, Ahmed
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Adult ,Bangladesh ,Sodium ,Cross-Sectional Studies ,Albumins ,Creatinine ,Hypertension ,Uromodulin ,Potassium ,Albuminuria ,Humans ,Kidney Diseases ,Essential Hypertension ,Biomarkers ,Glomerular Filtration Rate - Abstract
Hypertensive kidney damage results in glomerular as well as tubular dysfunction. Albuminuria is a well-known marker of glomerular damage. On the other hand, urinary uromodulin is increasingly considered as a potential biomarker of early tubular dysfunction. The aim of the study was to assess glomerular and tubular function of the kidney by measuring urinary albumin and uromodulin excretion in hypertensive subjects. This cross-sectional study was conducted from July 2018 to June 2019 in Hypertension Clinic of Dhaka Medical College Hospital, Dhaka and Kidney Care and Research Centre, Sonargaon, Narayanganj, Bangladesh. In this study 122 hypertensive subjects with age30 years, duration of hypertension5 years, without accelerated or malignant BP, absence of dipstick proteinuria and eGFR60ml/min were included. There were also 33 normotensive individuals included as healthy controls. Albumin-creatinine ratio (uACR mg/g), urine uromodulin-creatinine ratio (uUMODμg/g), urinary sodium-creatinine ratio (mEq/g) and potassium-creatinine ratio (mEq/g) were measured from single morning spot urine sample. Urinary uromodulin levels were measured by ELISA method. The hypertensive and normotensive subjects were age matched 49.0±12.0 vs. 48.0±11.0, years (p=NS). The mean uACR was 29.0±65.0 versus 5.6±2.7mg/g, (p0.001) respectively. The median uUMOD in hypertensive subjects was 3.38 (1.73-9.06) and in normotensives 3.85(2.28-5.69) μg/g (p=non significant). Multivariate analysis showed significant inverse association between diastolic blood pressure and urinary uromodulin excretion. A uUMOD cut-off of 2.9 (25th percentile) showed eGFR, urinary sodium and potassium excretions were significantly lower at low uromodulin group. The glomerular involvement was found in 21.0% of hypertensive subjects as evidenced by albuminuria. No difference was observed in urinary uromodulin level between hypertensive and normotensive subjects. Low urinary uromodulin level was associated with lower eGFR, Na+ and K+ excretion which indicate simultaneous tubular and glomerular involvement.
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- 2022
5. C1 monotone cubic Hermite interpolant.
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Robert J. Cripps and M. Z. Hussain
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- 2012
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6. Shape preserving surface data visualization using rational bi-cubic functions.
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M. Z. Hussain and S. Bashir
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- 2011
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7. Smooth polynomial approximation of spiral arcs.
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Robert J. Cripps, M. Z. Hussain, and S. Zhu
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- 2010
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8. Role of Oral Misoprostol in First Trimester Abortion: A Prospective Study at CMH, Dhaka, Bangladesh
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M. Z. Hussain and S. K. Chowdhury
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Pregnancy ,education.field_of_study ,medicine.medical_specialty ,business.industry ,Obstetrics ,medicine.medical_treatment ,Population ,medicine.disease ,Medical abortion ,Incomplete Abortion ,Obstetrics and gynaecology ,medicine ,Gestation ,business ,Prospective cohort study ,education ,Misoprostol ,medicine.drug - Abstract
Background: Misoprostol has been used for medical abortion. We conducted this prospective study to see the efficacy of oral misoprostol in our tertiary Hospital. Objective: Objective of this study was to assess the efficiency, safety and compliance of misoprostol in first trimester abortion. Materials and Methods: This prospective study was undertaken in obstetrics and gynecology dept of CMH Dhaka, Bangladesh from July 2014 up to Dec 2014. A total 50 patients of incomplete abortion (54%), missed abortion (30%), anembryonic pregnancy (14%) and inevitable abortion (2%) of s of gestation were the targeted population. Study population was diagnosed from history, physical examination and ultrasonogram had received 600 microgram misoprostol orally. If the pregnancy was not completely evacuated at this time another dose of misoprostol was given. All women returned for follow-up care 7 days later. If the pregnancy was not completely evacuated at this time, women underwent immediate surgical evacuation. Efficacy was defined as the percent of women discharged from the study without need for surgical intervention. Results: 30 patients had complete evacuation after 1st dose, 12 cases needed 2nd dose and only 2 cases needed 3rd dose. Remaining 6 cases needed surgical evacuation. Efficacy was satisfactory (85%) and analysis revealed statistically significant (p 0.05). Conclusion: Management of first trimester abortion with oral misoprostol is highly effective and highly acceptable.
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- 2020
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9. Nitrate Leaching from Continuous Corn, Perennial Grasses, and Poplar in the US Midwest
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Stephen K. Hamilton, Ajay Kumar Bhardwaj, G. Philip Robertson, Bruno Basso, and M. Z. Hussain
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Environmental Engineering ,Perennial plant ,biology ,Sowing ,04 agricultural and veterinary sciences ,Miscanthus ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,biology.organism_classification ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,Nitrate ,chemistry ,Agronomy ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Panicum virgatum ,Drainage ,Leaching (agriculture) ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Leaching from annual corn (Zea mays L.) crops is a primary source of nitrate (NO3−) pollution of ground and surface waters. Here, we compare NO3− losses from no‐till corn with losses from various alternative perennial cropping systems (switchgrass [Panicum virgatum L.], miscanthus [Miscanthus ×giganteus J.M. Greef & Deuter ex Hodkinson & Renvoiz], a native grass mixture, and restored prairie), as well as hybrid poplar (Populus nigra L. × P. maximowiczii A. Henry ‘NM6’), all grown on a well‐drained soil in Michigan. Soil water was sampled from below the root zone using suction cup samplers during nonfrozen periods (March–November) between 2009 and 2016. Leaching was estimated from NO3− concentrations in soil water and modeled drainage (percolation) rates. Drainage rates were not significantly different among crops, constituting ∼30% of total annual precipitation. Aboveground net primary production (Mg ha−1 yr−1) averaged across the 7 yr was highest in poplar (30.8 ± 1.9 [SE]) followed by miscanthus (23.9 ± 2.4) and corn (20.4 ± 0.9). Volume‐weighted mean NO3− concentrations (mg N L−1) and NO3− leaching (kg ha−1 yr−1) averaged across the 7 yr were 9.2 and 34.1, 2.3 and 5.9, and 3.0 and 7.2, respectively, for corn, perennial grasses and poplar. Approximately 10 to 32% of applied N was lost as NO3− from these crops, with the highest percent losses from poplar (32%) followed by corn (20%). Perennial cropping systems leached considerably more NO3− in first few years after planting, but over 7 yr they lost much less NO3− than corn. Perennial crops may therefore help ameliorate NO3− pollution in agricultural landscapes even if they receive modest N fertilization.
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- 2019
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10. Evapotranspiration and water use efficiency of continuous maize and maize and soybean in rotation in the upper Midwest U.S
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Kurt D. Thelen, M. Z. Hussain, G. P. Robertson, Ajay Kumar Bhardwaj, Bruno Basso, and Stephen K. Hamilton
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0208 environmental biotechnology ,Soil Science ,Growing season ,04 agricultural and veterinary sciences ,02 engineering and technology ,Biology ,020801 environmental engineering ,Agronomy ,Evapotranspiration ,Yield (wine) ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,DNS root zone ,Soil horizon ,Water-use efficiency ,Agronomy and Crop Science ,Stover ,Earth-Surface Processes ,Water Science and Technology - Abstract
This study examined evapotranspiration (ET) from no-till, rainfed maize and soybean during three growing seasons (May-Sep) of normal rainfall years (2009, 2010, 2011) and a drought year (2012) in Michigan, USA, based on daily soil water uptake measured by time-domain reflectometry at multiple depths through the root zone. During normal rainfall years, growing-season ET was similar between continuous maize (mean ± standard deviation: 471 ± 47 mm) and maize in rotation (469 ± 51 mm). During the drought year, ET decreased by only 3% for continuous maize but by 20% for maize in rotation. During the normal rainfall years, ET for soybean (453 ± 34 mm) was statistically indistinguishable from ET for maize, and was lower during the drought year (333 mm). Water use efficiency (WUE), calculated from harvest yield (grain + corn stover) and ET, was 25.3 ± 4.2 kg ha−1 mm-1 for continuous maize and 27.3 ± 3.1 kg ha−1 mm−1 for maize in rotation during the normal rainfall years, whereas WUEs for both continuous maize and maize in rotation were much lower in the 2012 drought year (14.0 and 15.5 kg ha−1 mm−1, respectively), coincident with lower production. Soybean had a much lower WUE than maize during the three normal years (6.95 ± 0.96 kg ha−1 mm−1) and the drought year (4.57 kg ha−1 mm−1), also explained by lower yield. Both maize and soybean tended to use all available water in the soil profile; there was no consistent difference in ET between these crops, while yield varied markedly from year to year.
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- 2019
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11. Salmonella Hepatitis - A Case Report
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M. Z. Hussain and S. K. Chowdhury
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Salmonella hepatitis is a rare complication of Typhoid fever in tropics. Typhoid fever is an infectious disease associated with high morbidity and mortality. The classical pattern of presentation is continuous fever with a “step ladder”rise, headache, abdominal pain, diarrhea, constipation, and relative bradycardia. In a rare instance, Typhoid fever presented with the feature of acute hepatitis like hepatomegaly and deranged liver functions with hepatic encephalopathy. After taking proper informed consent,we have reported a young patient who presented with low-grade fever, diarrhea,and jaundice. Subsequently he was found to have acute salmonella hepatitis secondary to typhoid fever. Recognition of Salmonella hepatitis is of clinical importance as it can mimic acute viral hepatitis. Early institution of specific therapeutic intervention and supportive care improve the prognosis in these patients.
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- 2020
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12. Estimating solar radiation from temperature
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ANIL SHARMA, U. A. SONI, H.K. RAI, M. Z. HUSSAIN, SUBHASH CHANDER, A. K. MISHRA, MUKESH SEHGAL, and NAVEEN KALRA
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Solar radiation ,Maximum and minimum temperatures ,Agriculture - Published
- 2005
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13. Evapotranspiration is resilient in the face of land cover and climate change in a humid temperate catchment
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Christopher Lowrie, G. P. Robertson, M. Z. Hussain, Stephen K. Hamilton, and Bruno Basso
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Hydrology ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,0208 environmental biotechnology ,Climate change ,Wetland ,02 engineering and technology ,Land cover ,Vegetation ,15. Life on land ,01 natural sciences ,6. Clean water ,020801 environmental engineering ,Catchment hydrology ,Water balance ,13. Climate action ,Agricultural land ,Evapotranspiration ,Environmental science ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
In temperate humid catchments, evapotranspiration returns more than half of the annual precipitation to the atmosphere, thereby determining the balance available to recharge groundwaters and support stream flow and lake levels. Changes in evapotranspiration rates and, therefore, catchment hydrology could be driven by changes in land use or climate. Here, we examine the catchment water balance over the past 50 years for a catchment in southwest Michigan covered by cropland, grassland, forest, and wetlands. Over the study period, about 27% of the catchment has been abandoned from row‐crop agriculture to perennial vegetation and about 20% of the catchment has reverted to deciduous forest, and the climate has warmed by 1.14 °C. Despite these changes in land use, the precipitation and stream discharge, and by inference catchment‐scale evapotranspiration, have been stable over the study period. The remarkably stable rates of evapotranspirative water loss from the catchment across a period of significant land cover change suggest that rainfed annual crops and perennial vegetation do not differ greatly in evapotranspiration rates, and this is supported by measurements of evapotranspiration from various vegetation types based on soil water monitoring in the same catchment. Compensating changes in the other meteorological drivers of evaporative water demand besides air temperature—wind speed, atmospheric humidity, and net radiation—are also possible but cannot be evaluated due to insufficient local data across the 50‐year period. Regardless of the explanation, this study shows that the water balance of this landscape has been resilient in the face of both land cover and climate change over the past 50 years.
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- 2018
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14. Enhanced evapotranspiration was observed during extreme drought from Miscanthus, opposite of other crops
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M. Z. Hussain, Evan H. DeLucia, Éva Joó, Marcelo Zeri, and Carl J. Bernacchi
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0106 biological sciences ,010504 meteorology & atmospheric sciences ,biology ,Renewable Energy, Sustainability and the Environment ,Vapour Pressure Deficit ,Eddy covariance ,Primary production ,Forestry ,Miscanthus ,biology.organism_classification ,01 natural sciences ,Agronomy ,Evapotranspiration ,Environmental science ,Miscanthus giganteus ,Water-use efficiency ,Waste Management and Disposal ,Agronomy and Crop Science ,010606 plant biology & botany ,0105 earth and related environmental sciences - Published
- 2017
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15. Depression among Medical Students of Bangladesh
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S R, Tareq, R A, Likhon, S N, Rahman, S, Akter, M S, Basher, M S, Hasan, M Z, Hussain, and M K, Khan
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Male ,Bangladesh ,Cross-Sectional Studies ,Students, Medical ,Depression ,Surveys and Questionnaires ,Humans ,Female - Abstract
Now a days depression is one of the leading cause of disabilities all over the world. Depression leads to a wide range of disorders and affects people of all communities. Medical students pass through a relatively high level of stress. Several studies revealed that anxiety and depression is significantly prevalent among medical students and often it persists even when they become physicians. The study was designed with an aim to estimate the prevalence of depression among the medical students of Bangladesh. The cross sectional descriptive type of observational study was conducted among randomly selected 399 Bangladeshi students of third year MBBS from six (6) randomly selected public medical colleges of Bangladesh from February 2017 to July 2017. Data were collected by a semi-structured self-administered questionnaire containing Beck's Depression Inventory. Data were entered and analyzed by SPSS version 20.0. Among 399 medical students, 45.6% were male and 54.4% were female. Regarding presence of depression among the medical students, 35.8% students had normal score. More than one fourth of the students (25.1%) had mild mood disturbance. Borderline clinical depression was found in 15.5% and moderate depression was found in 18.0% of the students. Severe depression was found in 5.3% students and one (0.3%) student was suffering from extreme depression. Overall 39.1% students were suffering from different levels of depression. Depression was prevalent more in female students (45.6%) than male students (31.3%). Suicidal tendency was present in 18.8% students. Among them 14.3% had thoughts of killing themselves but they would not carry them out; 3% would like to kill themselves and 1.5% would kill themselves if they had the chance. Suicidal tendency was also a bit higher in female students (19.3%) than male students (18.1%). A significant number (39.1%) of medical students of Bangladesh are suffering from depression and many of them (18.8%) have suicidal tendency which demands immediate attention of the authority. The findings of the study warrant a need for psychiatric counseling and support services for vulnerable students.
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- 2020
16. Risk Factors for Hypertension in Young Adults of Bangladesh
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G K, Paul, K K, Karmoker, B, Sen, M Z, Hussain, M S, Hasan, and M K, Khan
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Adult ,Male ,Rural Population ,Bangladesh ,Heart Diseases ,Urban Population ,Blood Pressure ,Comorbidity ,Middle Aged ,Young Adult ,Social Class ,Ischemia ,Risk Factors ,Hypertension ,Diabetes Mellitus ,Humans ,Female - Abstract
Hypertension is a major public health challenge to population in socio-economic and epidemiological transition. It is a risk factor for cardiovascular mortality which accounts for 20-50 per cent of all deaths. Hypertension has been recognized among young adults more frequently in recent years. Data regarding hypertension in Bangladesh is often insufficient. The purpose of the study was to find out the risk factors of hypertension in young adults of Bangladesh. The study was conducted among 322 purposively selected young adults aged 20 to 49 years attending in the outpatient department of one public and five private hospitals of Mymensingh and Dhaka division of Bangladesh during the period of January 2018 to December 2018. More than half (54.4%) of the patients were at or below the age of 40 years. Mean age of the patients was 38.7±7.8 years and 58.7% were male. Maximum patients (87.6%) were married and with variable educational and occupational status. More than three fourth of the patients (76.7%) were from urban area whereas 14.3% from rural and 9.0% were from sub-urban area. Family history of hypertension was positive in 86.6% of patients. Blood pressure was categorized according to JNC 7. About half (49.4%) of the patients were stage I hypertensive; 22.4% were stage II hypertensive and 28.3% were pre-hypertensive. The major risk factor was tobacco smoking (46.0%), obesity (29.2%), dyslipidaemia (25.2%), high salt intake 21.8% and use of chewable tobacco (13.7%). Serum creatinine was found raised in 11.5%, cardiomegaly in 2.2% and concentric left ventricular hypertrophy in 18.6% of patients. In 38.5% patients hypertension was complicated affecting heart (27.0%) and kidney (11.5%). Common comorbidities were ischaemic heart diseases (20.5%) and diabetes mellitus (13.4%). Tobacco use, obesity, dyslipidaemia and high salt intake are the major modifiable risk factors found in hypertensive young adults. In addition to medication these factors should be addressed for prevention and effective control of hypertension.
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- 2020
17. Comparative water use by maize, perennial crops, restored prairie, and poplar trees in the US Midwest
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S K Hamilton, M Z Hussain, A K Bhardwaj, B Basso, and G P Robertson
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evapotranspiration ,grasslands ,crops ,trees ,biofuels ,water balance ,Environmental technology. Sanitary engineering ,TD1-1066 ,Environmental sciences ,GE1-350 ,Science ,Physics ,QC1-999 - Abstract
Water use by plant communities across years of varying water availability indicates how terrestrial water balances will respond to climate change and variability as well as to land cover change. Perennial biofuel crops, likely grown mainly on marginal lands of limited water availability, provide an example of a potentially extensive future land cover conversion. We measured growing-season evapotranspiration (ET) based on daily changes in soil profile water contents in five perennial systems—switchgrass, miscanthus, native grasses, restored prairie, and hybrid poplar—and in annual maize (corn) in a temperate humid climate (Michigan, USA). Three study years (2010, 2011 and 2013) had normal growing-season rainfall (480–610 mm) whereas 2012 was a drought year (210 mm). Over all four years, mean (±SEM) growing-season ET for perennial systems did not greatly differ from corn (496 ± 21 mm), averaging 559 (±14), 458 (±31), 573 (±37), 519 (±30), and 492 (±58) mm for switchgrass, miscanthus, native grasses, prairie, and poplar, respectively. Differences in biomass production largely determined variation in water use efficiency (WUE). Miscanthus had the highest WUE in both normal and drought years (52–67 and 43 kg dry biomass ha ^−1 mm ^−1 , respectively), followed by maize (40–59 and 29 kg ha ^−1 mm ^−1 ); the native grasses and prairie were lower and poplar was intermediate. That measured water use by perennial systems was similar to maize across normal and drought years contrasts with earlier modeling studies and suggests that rain-fed perennial biomass crops in this climate have little impact on landscape water balances, whether replacing rain-fed maize on arable lands or successional vegetation on marginal lands. Results also suggest that crop ET rates, and thus groundwater recharge, streamflow, and lake levels, may be less sensitive to climate change than has been assumed.
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- 2015
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18. Risk of Abdominal Aortic Calcifications among End Stage Renal Disease Patients under Maintenance Haemodialysis
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M A, Razzak, K, Fatima, O F, Miah, A N, Hai, M Z, Hussain, M R, Anwar, M A, Faraji, D K, Debnath, G M, Hasan, and A, Zannat
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Bangladesh ,Renal Dialysis ,Risk Factors ,Case-Control Studies ,Calcinosis ,Humans ,Kidney Failure, Chronic ,Aorta, Abdominal ,Renal Insufficiency, Chronic - Abstract
Calcification of soft tissue and blood vessel wall occurs more frequently in dialyzed patients. The purpose of the present study was to estimate the risk of abdominal aortic calcification among end stage renal disease patients under maintenance haemodialysis. This case-control study was carried out in the Department of Nephrology at National Institute of Kidney Diseases and Urology (NIKDU), Dhaka and National Institute of Cardiovascular Disease and Hospital (NICVD), Dhaka, Bangladesh from January 2013 to December 2014 for a period of two (02) years. Chronic kidney disease in stage 5 {CKD-5(D)} patients older than 18 years on maintenance haemodialysis (MHD) for more than 3 months were selected as case group. And same age and sex non CKD patients were considered as control group. Serum calcium, serum albumin, serum phosphate and iPTH were estimated by semi-automated biochemistry analyzer from the Department of Biochemistry of NIKDU, Dhaka and NICVD, Dhaka. Plain X-ray abdomen in lateral view was performed for all patients. Total 100 patients were enrolled for this study of which 50 patients were in end stage renal disease (ESRD) group and the rest 50 patients were in non-CKD group. Abdominal aortic calcification on X ray was present in 22(44%) patients of ESRD group and 6(12%) patients of non CKD group of population. Mean±SD serum calcium (corrected) level was significantly high (p0.001) in ESRD patients (9.79±0.87) compared to non CKD group of population (9.13±0.70). Mean±SD of serum phosphate level was significantly higher (p0.001) in ESRD patients (5.71±0.96) compared to non CKD group of population (4.20±0.59). However, mean±SD iPTH level showed no significant difference between ESRD (25.33±51.98) and non CKD group of population (38.53±19.52), though iPTH level remain below the target level in ESRD group. Abdominal aortic calcification is significantly higher among ESRD subjects.
- Published
- 2019
19. The influence of drought and heat stress on long-term carbon fluxes of bioenergy crops grown in the Midwestern USA
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Marcelo Zeri, Evan H. DeLucia, M. Z. Hussain, Michael D. Masters, Carl J. Bernacchi, J. N. Miller, Éva Joó, and Nuria Gomez-Casanovas
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010504 meteorology & atmospheric sciences ,Perennial plant ,biology ,Physiology ,Eddy covariance ,Primary production ,Biomass ,Carbon sink ,04 agricultural and veterinary sciences ,Plant Science ,Miscanthus ,biology.organism_classification ,01 natural sciences ,Carbon cycle ,Agronomy ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Panicum virgatum ,0105 earth and related environmental sciences - Abstract
Perennial grasses are promising feedstocks for bioenergy production in the Midwestern USA. Few experiments have addressed how drought influences their carbon fluxes and storage. This study provides a direct comparison of ecosystem-scale measurements of carbon fluxes associated with miscanthus (Miscanthus × giganteus), switchgrass (Panicum virgatum), restored native prairie and maize (Zea mays)/soybean (Glycine max) ecosystems. The main objective of this study was to assess the influence of a naturally occurring drought during 2012 on key components of the carbon cycle and plant development relative to non-extreme years. The perennials reached full maturity 3-5 years after establishment. Miscanthus had the highest gross primary production (GPP) and lowest net ecosystem exchange (NEE) in 2012 followed by similar values for switchgrass and prairie, and the row crops had the lowest GPP and highest NEE. A post-drought effect was observed for miscanthus. Over the duration of the experiment, perennial ecosystems were carbon sinks, as indicated by negative net ecosystem carbon balance (NECB), while maize/soybean was a net carbon source. Our observations suggest that perennial ecosystems, and in particular miscanthus, can provide a high yield and a large potential for CO2 fixation even during drought, although drought may negatively influence carbon uptake in the following year, questioning the long-term consequence of its maintained productivity.
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- 2016
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20. Leaching losses of dissolved organic carbon and nitrogen from agricultural soils in the upper US Midwest
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Bruno Basso, Stephen K. Hamilton, M. Z. Hussain, and G. Philip Robertson
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Total organic carbon ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Perennial plant ,biology ,Miscanthus ,010501 environmental sciences ,biology.organism_classification ,01 natural sciences ,Pollution ,Nutrient ,Agronomy ,Dissolved organic carbon ,Soil water ,Environmental Chemistry ,Environmental science ,Water quality ,Leaching (agriculture) ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Leaching losses of dissolved organic carbon (DOC) and nitrogen (DON) from agricultural systems are important to water quality and carbon and nutrient balances but are rarely reported; the few available studies suggest linkages to litter production (DOC) and nitrogen fertilization (DON). In this study we examine the leaching of DOC, DON, NO3−, and NH4+ from no-till corn (maize) and perennial bioenergy crops (switchgrass, miscanthus, native grasses, restored prairie, and poplar) grown between 2009 and 2016 in a replicated field experiment in the upper Midwest U.S. Leaching was estimated from concentrations in soil water and modeled drainage (percolation) rates. DOC leaching rates (kg ha−1 yr−1) and volume-weighted mean concentrations (mg L−1) among cropping systems averaged 15.4 and 4.6, respectively; N fertilization had no effect and poplar lost the most DOC (21.8 and 6.9, respectively). DON leaching rates (kg ha−1 yr−1) and volume-weighted mean concentrations (mg L−1) under corn (the most heavily N-fertilized crop) averaged 4.5 and 1.0, respectively, which was higher than perennial grasses (mean: 1.5 and 0.5, respectively) and poplar (1.6 and 0.5, respectively). NO3− comprised the majority of total N leaching in all systems (59–92%). Average NO3− leaching (kg N ha−1 yr−1) under corn (35.3) was higher than perennial grasses (5.9) and poplar (7.2). NH4+ concentrations in soil water from all cropping systems were relatively low (
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- 2020
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21. Leaf and Ecosystem Gas Exchange Responses of Buffel Grass-Dominated Grassland to Summer Precipitation
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Chhakchhuak Lalrammawia, M. Z. Hussain, John Tenhunen, Dennis O. Otieno, Gnaana Saraswathi, and Kailash Paliwal
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Biomass (ecology) ,Stomatal conductance ,biology ,Ecology ,Soil Science ,Carbon sink ,Carbon sequestration ,biology.organism_classification ,Agronomy ,Cenchrus ciliaris ,Environmental science ,Ecosystem ,Precipitation ,Ecosystem respiration - Abstract
Sporadic rain events that occur during summer play an important role in the initiation of biological activity of semi-arid grasslands. To understand how ecosystem processes of a buffel grass ( Cenchrus ciliaris L.)-dominated grassland respond to summer rain events, an LI 6 400 gas exchange system was used to measure the leaf gas exchange and plant canopy chambers were used to measure net ecosystem CO 2 exchange (NEE) and ecosystem respiration ( R eco ), which were made sequentially during periods before rain (dry) and after rain (wet). Gross ecosystem photosynthesis (GEP) was estimated from NEE and R eco fluxes, and light use efficiency parameters were estimated using a rectangular hyperbola model. Prior to the monsoon rain, grassland biomass was non-green and dry exhibiting positive NEE (carbon source) and low GEP values during which the soil water became increasingly scarce. An initial rain pulse (60 mm) increased the NEE from pre-monsoon levels to negative NEE (carbon gain) with markedly higher GEP and increased green biomass. The leaf photosynthesis and leaf stomatal conductance were also improved substantially. The maximum net CO 2 uptake (i.e., negative NEE) was sustained in the subsequent period due to multiple rain events. As a result, the grassland acted as a net carbon sink for 20 d after first rain. With cessation of rain (drying cycle), net CO 2 uptake was reduced to lower values. High sensitivity of this grassland to rain suggests that any decrease in precipitation in summer may likely affect the carbon sequestration of the semiarid ecosystem.
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- 2015
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22. The biophysical link between climate, water, and vegetation in bioenergy agro-ecosystems
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Sarah Davis, M. Z. Hussain, Andy VanLoocke, Stephen W. Nesbitt, J. N. Miller, Carl J. Bernacchi, Matei Georgescu, and Justin E. Bagley
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Land use ,Renewable Energy, Sustainability and the Environment ,Natural resource economics ,Agroforestry ,Forestry ,Ecosystem services ,Bioenergy ,Greenhouse gas ,Environmental science ,Land use, land-use change and forestry ,Ecosystem ,Energy source ,Temporal scales ,Waste Management and Disposal ,Agronomy and Crop Science - Abstract
Land use change for bioenergy feedstocks is likely to intensify as energy demand rises simultaneously with increased pressure to minimize greenhouse gas emissions. Initial assessments of the impact of adopting bioenergy crops as a significant energy source have largely focused on the potential for bioenergy agroecosystems to provide global-scale climate regulating ecosystem services via biogeochemical processes. Such as those processes associated with carbon uptake, conversion, and storage that have the potential to reduce global greenhouse gas emissions (GHG). However, the expansion of bioenergy crops can also lead to direct biophysical impacts on climate through water regulating services. Perturbations of processes influencing terrestrial energy fluxes can result in impacts on climate and water across a spectrum of spatial and temporal scales. Here, we review the current state of knowledge about biophysical feedbacks between vegetation, water, and climate that would be affected by bioenergy-related land use change. The physical mechanisms involved in biophysical feedbacks are detailed, and interactions at leaf, field, regional, and global spatial scales are described. Locally, impacts on climate of biophysical changes associated with land use change for bioenergy crops can meet or exceed the biogeochemical changes in climate associated with rising GHG's, but these impacts have received far less attention. Realization of the importance of ecosystems in providing services that extend beyond biogeochemical GHG regulation and harvestable yields has led to significant debate regarding the viability of various feedstocks in many locations. The lack of data, and in some cases gaps in knowledge associated with biophysical and biochemical influences on land–atmosphere interactions, can lead to premature policy decisions.
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- 2014
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23. Carbon sink strength of a Mediterranean cork oak understorey: how do semi-deciduous and evergreen shrubs face summer drought?
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F. Costa e Silva, M. Z. Hussain, Jorge S. David, A.V. Correia, João Pereira, Alexandra Correia, and A.D. Rodrigues
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Ecology ,biology ,ved/biology ,Semi-deciduous ,ved/biology.organism_classification_rank.species ,Carbon sink ,Plant Science ,Understory ,Evergreen ,biology.organism_classification ,Shrub ,Agronomy ,Cistus salviifolius ,Environmental science ,Ecosystem ,Transpiration - Abstract
Questions How do semi-deciduous and evergreen shrubs exploit environmental resources during summer drought? What is the contribution of the understorey shrubby layer to ecosystem carbon assimilation? To what extent are carbon balance and transpiration impacted by a rain pulse? Location Cork oak open woodland in the Mediterranean region. Methods We used closed dynamic light and dark chambers to measure gas exchange (CO2 and H2O) in the dominant shrub understorey species Cistus salviifolius, Cistus crispus (semi-deciduous) and Ulex airensis (evergreen), together with plant physiological and morphological measurements during summer drought and autumn recovery. A hyperbolic light response model constrained by vapour pressure deficits was fitted for up-scaling shrub photosynthesis to the ecosystem level. The data were compared, on a daily and daytime basis, with gross primary productivity estimates from ecosystem eddy-covariance flux measurements. Results The onset of summer drought led to a significant leaf area reduction in semi-deciduous species. A general decrease in photosynthesis in all species was observed, while evapotranspiration and above-ground respiration fluxes contrasted among species during summer progression and autumn recovery. The shallow-rooted C. salviifolius was able to use light more efficiently than the other two species, although with poor stomatal control over water loss and consistently higher above-ground respiration rates, leading to lower water and carbon use efficiencies when compared with C. crispus. The deep-rooted shrub U. airensis maintained higher leaf water potentials and very low photosynthetic rates while decreasing transpiration rates throughout the summer drought. A summer rain pulse showed that shallow-rooted shrubs use water in an opportunistic way, with immediate leaf rehydration and concomitant photosynthesis increments. Conversely, deep-rooted shrubs (U. airensis) were unresponsive, only recovering photosynthesis with high soil water content. An opportunistic growth response may be disadvantageous to shallow-rooted shrubs in a future climate with extended dry summers and higher probability of rain pulse events. The prominent increase in transpiration rates and plant respiration costs observed during the dry conditions that followed the rain pulse, led to a reduced plant ability to recover after autumn rains. Conclusions The shrubs that naturaly colonized this montado understorey showed contrasting strategies to overcome summer drought, suggesting an efficient mosaic exploitation of seasonal environmental resources. The contribution of these shrubs to total ecosystem CO2 uptake during summer and autumn recovery was 17%. This high contribution implies that shrub density management decisions should consider a carbon balance perspective.
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- 2013
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24. Water use efficiency of perennial and annual bioenergy crops in central Illinois
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M. Z. Hussain, Carl J. Bernacchi, Marcelo Zeri, Kristina J. Anderson-Teixeira, and Evan H. DeLucia
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Atmospheric Science ,Ecology ,biology ,Paleontology ,Soil Science ,Biomass ,Forestry ,Row crop ,Miscanthus ,Aquatic Science ,Carbon sequestration ,biology.organism_classification ,Agronomy ,Bioenergy ,Panicum virgatum ,Environmental science ,Ecosystem ,Water-use efficiency ,Water Science and Technology - Abstract
[1] Sustainable bioenergy production depends upon the efficiency with which crops use available water to produce biomass and store carbon belowground. Therefore, water use efficiency (WUE; productivity vs. annual evapotranspiration, ET) is a key metric of bioenergy crop performance. We evaluate WUE of three potential perennial grass bioenergy crops, Miscanthus × giganteus (miscanthus), Panicum virgatum (switchgrass), and an assemblage of prairie species (28 species), and Zea mays–Glycine max rotation, during the establishment phase in Illinois. Ecosystem WUE (EWUE; net ecosystem productivity vs. ET) was highest in miscanthus, reaching a maximum value of 12.8 ± 0.3 kg ha–1 mm–1 in the third year, followed by switchgrass (7.5 ± 0.3 kg ha–1 mm–1) and prairie (3.9 ± 0.3 kg ha–1 mm–1); the row crop was the lowest. Besides EWUE, harvest-WUE (HWUE, harvested biomass vs. ET) and net biome productivity-WUE (BWUE, calculated as net ecosystem production – harvest vs. ET) were also estimated for all crops and years. After three years of establishment, HWUE and BWUE were highest in miscanthus (9.0 ± 2 and 3.8 ± 2.9 kg ha–1 mm–1, respectively) providing a net benefit to the carbon balance, while the row crops had a negative carbon balance and a negative BWUE. BWUE for maize/soybean indicate that this ecosystem would deplete the soil carbon stocks while using the water resources. Switchgrass had the second highest BWUE, while prairie was almost neutral indicating that long-term carbon sequestration for this agro-ecosystem would be sensitive to harvest timing with an early harvest removing more biomass, and thus carbon, from the field.
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- 2013
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25. Influence ofPseudomonas aeruginosabacteria on corrosion resistance of 304 stainless steel
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Esah Hamzah, M Z Hussain, Ahmad Abdolahi, and Zaharah Ibrahim
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Materials science ,biology ,Scanning electron microscope ,Pseudomonas aeruginosa ,General Chemical Engineering ,Metallurgy ,Biofilm ,Energy-dispersive X-ray spectroscopy ,General Chemistry ,biology.organism_classification ,medicine.disease_cause ,Corrosion ,medicine ,Pitting corrosion ,General Materials Science ,Layer (electronics) ,Bacteria - Abstract
Microbiologically influenced corrosion (MIC) is a corrosion phenomenon that is destructive to many industries. This research aims to investigate on the MIC behaviour of a 304 stainless steel (SS) substrate in a nutrient rich simulated seawater inoculated with Pseudomonas aeruginosa bacteria. Atomic force microscopy, scanning electron microscopy and energy dispersive spectroscopy (EDS) techniques were used to analyse MIC behaviour of 304 SS. Atomic force microscopy was used to observe the degree of pitting corrosion on 304 SS due to the presence of P. aeruginosa bacteria. Scanning electron microscopy and EDS were used to analyse the biofilm layer formed on 304 SS. The considerable feature was the severe pitting corrosion of 304 SS due to presence of P. aeruginosa in biofilm state.
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- 2013
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26. Future carbon dioxide concentration decreases canopy evapotranspiration and soil water depletion by field-grown maize
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Andrew D. B. Leakey, M. Z. Hussain, R. J. Cody Markelz, Ursula M. Ruiz-Vera, Donald R. Ort, Matthew H. Siebers, Carl J. Bernacchi, and Andy VanLoocke
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Canopy ,Stomatal conductance ,Time Factors ,Climate Change ,Photosynthesis ,Zea mays ,Soil ,Evapotranspiration ,Environmental Chemistry ,Water content ,General Environmental Science ,Transpiration ,Global and Planetary Change ,Ecology ,Free-air concentration enrichment ,Chemistry ,Water ,food and beverages ,Plant Transpiration ,Carbon Dioxide ,Circadian Rhythm ,Plant Leaves ,Agronomy ,Soil water ,Illinois ,Seasons ,Energy Metabolism - Abstract
Maize, in rotation with soybean, forms the largest continuous ecosystem in temperate North America, therefore changes to the biosphere-atmosphere exchange of water vapor and energy of these crops are likely to have an impact on the Midwestern US climate and hydrological cycle. As a C4 crop, maize photosynthesis is already CO2 -saturated at current CO2 concentrations ([CO2 ]) and the primary response of maize to elevated [CO2 ] is decreased stomatal conductance (gs ). If maize photosynthesis is not stimulated in elevated [CO2 ], then reduced gs is not offset by greater canopy leaf area, which could potentially result in a greater ET reduction relative to that previously reported in soybean, a C3 species. The objective of this study is to quantify the impact of elevated [CO2 ] on canopy energy and water fluxes of maize (Zea mays). Maize was grown under ambient and elevated [CO2 ] (550 μmol mol(-1) during 2004 and 2006 and 585 μmol mol(-1) during 2010) using Free Air Concentration Enrichment (FACE) technology at the SoyFACE facility in Urbana, Illinois. Maize ET was determined using a residual energy balance approach based on measurements of sensible (H) and soil heat fluxes, and net radiation. Relative to control, elevated [CO2 ] decreased maize ET (7-11%; P 0.01) along with lesser soil moisture depletion, while H increased (25-30 W m(-2) ; P 0.01) along with higher canopy temperature (0.5-0.6 °C). This reduction in maize ET in elevated [CO2 ] is approximately half that previously reported for soybean. A partitioning analysis showed that transpiration contributed less to total ET for maize compared to soybean, indicating a smaller role of stomata in dictating the ET response to elevated [CO2 ]. Nonetheless, both maize and soybean had significantly decreased ET and increased H, highlighting the critical role of elevated [CO2 ] in altering future hydrology and climate of the region that is extensively cropped with these species.
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- 2013
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27. Altered Belowground Carbon Cycling Following Land-Use Change to Perennial Bioenergy Crops
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Christopher K. Black, Carl J. Bernacchi, Marcelo Zeri, Kristina J. Anderson-Teixeira, Evan H. DeLucia, Michael D. Masters, and M. Z. Hussain
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Biomass (ecology) ,Ecology ,Perennial plant ,biology ,Miscanthus ,Soil carbon ,biology.organism_classification ,Carbon cycle ,Soil respiration ,Agronomy ,Bioenergy ,Environmental Chemistry ,Environmental science ,Ecosystem ,Ecology, Evolution, Behavior and Systematics - Abstract
Belowground carbon (C) dynamics of terrestrial ecosystems play an important role in the global C cycle and thereby in climate regulation. Globally, land-use change is a major driver of changes in belowground C storage. The emerging bioenergy industry is likely to drive widespread land-use changes, including the replacement of annually tilled croplands with perennial bioenergy crops, and thereby to impact the climate system through alteration of belowground C dynamics. Mechanistic understanding of how land-use changes impact belowground C storage requires elucidation of changes in belowground C flows; however, altered belowground C dynamics following land-use change have yet to be thoroughly quantified through field measurements. Here, we show that belowground C cycling pathways of establishing perennial bioenergy crops (0- to 3.5-year-old miscanthus, switchgrass, and a native prairie mix) were substantially altered relative to row crop agriculture (corn-soy rotation); specifically, there were substantial increases in belowground C allocation (>400%), belowground biomass (400–750%), root-associated respiration (up to 2,500%), moderate reductions in litter inputs (20–40%), and respiration in root-free soil (up to 50%). This more active root-associated C cycling of perennial vegetation provides a mechanism for observed net C sequestration by these perennial ecosystems, as well as commonly observed increases in soil C under perennial bioenergy crops throughout the world. The more active root-associated belowground C cycle of perennial vegetation implies a climate benefit of grassland maintenance or restoration, even if biomass is harvested annually for bioenergy production.
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- 2013
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28. Evapotranspiration is resilient in the face of land cover and climate change in a humid temperate catchment
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Christopher Lowrie, Bruno Basso, G. Philip Robertson, M. Z. Hussain, and Stephen K. Hamilton
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Hydrology ,geography ,geography.geographical_feature_category ,Watershed ,010504 meteorology & atmospheric sciences ,0207 environmental engineering ,Climate change ,Wetland ,02 engineering and technology ,Vegetation ,Land cover ,15. Life on land ,01 natural sciences ,6. Clean water ,Water balance ,13. Climate action ,Evapotranspiration ,Temperate climate ,Environmental science ,020701 environmental engineering ,0105 earth and related environmental sciences - Abstract
In temperate humid catchments, evapotranspiration returns more than half of the annual precipitation to the atmosphere, thereby determining the balance available to recharge groundwaters and support stream flow and lake levels. Changes in evapotranspiration rates and therefore catchment hydrology could be driven by changes in land use or climate. Here we examine the catchment water balance over the past 50 y for a catchment in southwest Michigan covered by cropland, grassland, forest, and wetlands. Over the study period about 27% of the catchment has been abandoned from row-crop agriculture to perennial vegetation and about 20% of the catchment has reverted to deciduous forest, and the climate has warmed by 1.14°C. Despite these changes in land use, precipitation and stream discharge, and by inference catchment-scale evapotranspiration, have been stable over the study period. The remarkably stable rates of evapotranspirative water loss from the catchment across a period of significant land cover change suggest that rainfed annual crops and perennial vegetation do not differ greatly in evapotranspiration rates, and this is supported by measurements of evapotranspiration from various vegetation types based on soil water monitoring in the same catchment. Compensating changes in the other meteorological drivers of evaporative water demand besides air temperature—wind speed, atmospheric humidity, and net radiation—are also possible, but cannot be evaluated due to insufficient local data across the 50-y period. Regardless of the explanation, this study shows that the water balance of this landscape has been resilient in the face of both land cover and climate change over the past 50 y.
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- 2016
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29. Summer drought influence on CO2 and water fluxes of extensively managed grassland in Germany
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H. Mirzae, Margarete Wartinger, Katherine E. Owen, Markus Schmidt, Thomas Grünwald, Ch. Bernhofer, Yuelin Li, M. Z. Hussain, Nguyen Quoc Dinh, Dennis O. Otieno, and John Tenhunen
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Canopy ,Biomass (ecology) ,Ecology ,Water flow ,Eddy covariance ,Primary production ,Atmospheric sciences ,Evapotranspiration ,Environmental science ,Animal Science and Zoology ,Ecosystem respiration ,Water-use efficiency ,Agronomy and Crop Science - Abstract
Net ecosystem CO2 exchange (NEE) and water fluxes of extensively managed grassland in Germany were measured in a dry year, 2003 and a normal year, 2004 using eddy covariance. Empirical descriptions of canopy capacities (light utilization efficiency and canopy capacity for maximum carboxylation) and inherent water use efficiency (IWUE*) were computed to indicate the grassland's response to environmental and management conditions. Compared with 2004, 2003 was characterized by a 2.5 °C rise in summer mean temperature and an annual precipitation deficit of 286 mm, which was almost one-third below the average precipitation of the normal year 2004 and the long-term annual average (1959–2005). Annual net water balance (precipitation minus evapo-transpiration) in 2003 and 2004 were 85 mm and 361 mm, respectively. Slightly higher IWUE* in 2003 indicates the grassland's sensitivity to drought. The grassland provided an annual gross primary production (GPP) and ecosystem respiration (Reco) of 1022 and 728 g C m−2 respectively in 2003, as compared to their corresponding values of 1233 and 973 g C m−2 in 2004. Drought-induced biomass senescence caused GPP reduction in 2003, which in turn affected the ecosystem respiration. Light explained more than 80% of NEE variability during canopy development and as a result, annual NEE in 2003 and 2004 were −295 and −260 g C m−2, respectively. Taking into account the exported carbon by biomass harvest, we calculated net biome productivity (NBP) of −113 g C m−2 yr−1. We conclude that this managed grassland acted as a moderate carbon sink, despite the difference in environmental and management conditions.
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- 2011
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30. Prospects of biodiesel production from microalgae in India
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Shakeel A. Khan, Uttam Chand Banerjee, Rashmi, Shiv Prasad, and M. Z. Hussain
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Biodiesel ,Engineering ,Waste management ,Renewable Energy, Sustainability and the Environment ,business.industry ,Greenhouse gas ,Biodiesel production ,Fossil fuel ,Biomass ,Carbon sequestration ,business ,Biorefinery ,Renewable energy - Abstract
Energy is essential and vital for development, and the global economy literally runs on energy. The use of fossil fuels as energy is now widely accepted as unsustainable due to depleting resources and also due to the accumulation of greenhouse gases in the environment. Renewable and carbon neutral biodiesel are necessary for environmental and economic sustainability. Biodiesel demand is constantly increasing as the reservoir of fossil fuel are depleting. Unfortunately biodiesel produced from oil crop, waste cooking oil and animal fats are not able to replace fossil fuel. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Production of biodiesel using microalgae biomass appears to be a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. Microalgae are photosynthetic microorganisms which convert sunlight, water and CO2 to sugars, from which macromolecules, such as lipids and triacylglycerols (TAGs) can be obtained. These TAGs are the promising and sustainable feedstock for biodiesel production. Microalgal biorefinery approach can be used to reduce the cost of making microalgal biodiesel. Microalgal-based carbon sequestration technologies cover the cost of carbon capture and sequestration. The present paper is an attempt to review the potential of microalgal biodiesel in comparison to the agricultural crops and its prospects in India.
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- 2009
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31. CO2 exchange and biomass development of the herbaceous vegetation in the Portuguese montado ecosystem during spring
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H. Mirzae, Yuelin Li, L. Siebke, M. Z. Hussain, John Tenhunen, Thomas Foken, João Pereira, Dennis O. Otieno, Nuno Ribeiro, and Markus Schmidt
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Biomass (ecology) ,Ecology ,Plant community ,Understory ,Vegetation ,Herbaceous plant ,Productivity (ecology) ,Agronomy ,Environmental science ,Animal Science and Zoology ,Ecosystem ,Ecosystem respiration ,Agronomy and Crop Science - Abstract
Montado are spatially heterogeneous ecosystems that are economically important for the production of cork and herbaceous biomass that provide fodder for animals. Understanding of how trees and the herbaceous layer interact to determine pasture yield and the overall CO2 exchange of the herbaceous layer is crucial. Portable chambers were used to study CO2 exchange by the herbaceous layer component of the montado ecosystem in southern Portugal. Biomass, Net herbaceous layer CO2 exchange (NEE) and respiration (Reco) were measured in the open and understory locations between March and May, during the active growing period. Parameter fits on the NEE data were performed using empirical hyperbolic light response model, while ecosystem respiration (Reco) data were fitted with a two-parameter exponential model. Annual green biomass productions were 405.8 ± 9.0 and 250.6 ± 6.3 g m−2 in the open and the understory, respectively. The respective maximum NEE during the day were −24.0 ± 2.9 and −9.6 ± 2.2 μmol m−2 s−1 while maximum Reco were 20.6 ± 2.2 and 10.0 ± 1.6 μmol m−2 s−1, occurring in April. Photosynthetic photon flux density (PPFD) explained more that 70% of variations in daytime NEE while soil temperature at 10 cm depth (Tsoil) explained >50% of the variations in Reco under non-limiting soil moisture conditions. Both the herbaceous layer communities shared similar plant functional types and no significant difference in nutrient nitrogen (N) occurred between them. The two herbaceous layer components shared similar physiological characteristics and differences that arose in their CO2 uptake capacities and green biomass production were the result of microclimatic differences created by tree shading.
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- 2009
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32. Responses of CO2 Exchange and Primary Production of the Ecosystem Components to Environmental Changes in a Mountain Peatland
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Jan Muhr, Dennis O. Otieno, A. Nishiwaki, Gunnar Lischeid, Margarete Wartinger, M. Z. Hussain, and Werner Borken
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Biomass (ecology) ,Peat ,Ecology ,Environmental Chemistry ,Primary production ,Environmental science ,Species diversity ,Ecosystem ,Vegetation ,Leaf area index ,Ecosystem respiration ,Ecology, Evolution, Behavior and Systematics - Abstract
The complexity of natural ecological systems presents challenges for predicting the impact of global environmental changes on ecosystem structure and function. Grouping of plants into functional types, that is, groups of species sharing traits that govern their mechanisms of response to environmental perturbations, reduce the complexity of species diversity to a few key plant types for better understanding of ecosystem responses. Chambers were used to measure CO2 exchange in grass and moss growing together in a mountain peatland in southern Germany to assess variations in their response to environmental changes and how they influence ecosystem CO2 exchange. Parameter fits and comparison for net ecosystem exchange (NEE) in two ecosystem components were conducted using an empirical hyperbolic light response model. Annual green biomass production was 320 and 210 g dwt m−2, whereas mean maximum NEE was –10.0 and –5.0 μmol m−2 s−1 for grass and moss, respectively. Grass exhibited higher light use efficiency (α) and maximum gross primary production [(β+γ)2000]. Leaf area index explained 93% of light use and 83% of overall production by the grass. Peat temperature at 10-cm depth explained more than 80% of the fluctuations in ecosystem respiration (R eco). Compared to grass, moss NEE was more sensitive to ground water level (GWL) draw-down and hence could be more vulnerable to changes in precipitation that result in GWL decline and may be potentially replaced by grass and other vegetation that are less sensitive.
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- 2009
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33. A single drought event of 100‐year recurrence enhances subsequent carbon uptake and changes carbon allocation in experimental grassland communities
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Juergen Kreyling, Anke Jentsch, Carl Beierkuhnlein, Heydar Mirzaei, John Tenhunen, M. Z. Hussain, and Yuelin Li
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geography ,geography.geographical_feature_category ,Vegetative reproduction ,Ecology ,food and beverages ,Soil Science ,Climate change ,Plant Science ,Grassland ,Extreme weather ,Productivity (ecology) ,Agronomy ,Respiration ,Environmental science ,Compensatory growth (organism) ,Ecosystem - Abstract
Evidence suggests that the expected increase in frequency and magnitude of extreme weather events during climate change will alter plant productivity. Therefore, extreme weather events might also be capable of changing C sequestration and allocation. Here, experimental grassland communities of two species compositions, differing in their diversity, were exposed either to a simulated single drought or to a heavy-rainfall event. The magnitude of these manipulations imitated the local 100-year weather extreme according to extreme-value statistics. Effects on Net Ecosystem CO2 Exchange (NEE in lmol m–2 s–1) as well as aboveground biomass production and leaf-area index (LAI) were recorded from prior to the manipulations until two months after the manipulations ended. Initial light utilization efficiency and maximum NEE increased after the drought. No change in the respiration was detected and maximum uptake capacity (GPPmax) was 15% higher for the drought-manipulated plots compared to controls, which indicates an enhanced CO2 uptake into the systems. The level of diversity was also found to alter the lightresponse curves, increasing respiration and maximum NEE to a higher degree than drought in the more diverse compared to the less diverse community. This resulted in an increase of GPPmax by 55%. No significant interactions between species composition and weather manipulations were detected. Interestingly, aboveground biomass production was not significantly affected by weather manipulations, even though LAI increased due to drought. This increase was caused by a decrease in the ratio between reproductive and vegetative growth. The heavyrainfall manipulation resulted in no significant effects. Our data suggest that C sequestration can be enhanced by a single weather event. However the importance, long-term duration, and thresholds or turning points of such effects need to be investigated further as intensification of weather extremes is currently emerging as one of the most important facets of climate change.
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- 2008
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34. Assessment and up-scaling of CO2 exchange by patches of the herbaceous vegetation mosaic in a Portuguese cork oak woodland
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Nuno Ribeiro, John Tenhunen, M. Z. Hussain, Dennis O. Otieno, Yuelin Li, João Pereira, J. Banza, Markus Schmidt, Thomas Foken, Luis Aires, Heydar Mirzaei, Lukas Siebicke, and Casimiro Pio
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Atmospheric Science ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,biology ,Ecology ,Eddy covariance ,Biometeorology ,Forestry ,Understory ,Woodland ,Vegetation ,Quercus suber ,Atmospheric sciences ,biology.organism_classification ,Grassland ,Environmental science ,Ecosystem ,Agronomy and Crop Science - Abstract
Long-term eddy covariance measurements over a montado oak woodland in southern Portugal have documented a vulnerability to predicted decreases in springtime rainfall, since water availability during spring limits annual CO 2 gain, the growth of fodder for animals, and the production of cork by Quercus suber . The current study examined CO 2 exchange of three different herbaceous vegetation components distributed over montado landscapes and within the footprint of long-term landscape eddy covariance monitoring studies. Simultaneous measurements with eddy covariance at two sites and with manually operated chambers at multiple locations revealed that slow drainage of shallow basins, the onset of drying at higher sites and a high release of CO 2 below tree canopies significantly influenced the overall course of montado ecosystem gas exchange during the spring. Hyperbolic light response models were employed to up-scale and compare herbaceous gas exchange with landscape net ecosystem CO 2 flux. The up-scaling demonstrates the importance of the herbaceous understory in determining annual carbon balance of the montado and suggests a relatively small additional CO 2 uptake by the tree canopies and boles, i.e., by the aboveground tree compartment, during springtime. Annual flux totals obtained during the extremely dry year 2005 and a normal precipitation year 2006 for the oak woodland and a nearby grassland were essentially the same, indicating that both ecosystems similarly exploit available resources. Based on comparisons with additional temperate grasslands, we can visualize the montado herbaceous cover as a typical European grassland canopy, but where temperature fluctuations in winter control uptake, and where total production depends on springtime rainfall as it controls phenological events and eventually dieback of the vegetation. On the other hand, tree canopies remain active longer during late spring and early summer, modifying the montado response from that of grassland. Uncertainties in flux estimates via both chamber and eddy covariance methodologies currently prevent a full understanding of vegetation/atmosphere coupling, of the recycling of CO 2 between the understory communities and trees, and of relationships between exchange rates of individual components of the vegetation mosaic and overall carbon and water balances in montado landscapes.
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- 2008
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35. Lactate down-regulates cellular poly(ADP-ribose) formation in cultured human skin fibroblasts
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Jürgen Weinreich, H. D. Becker, S. Wagner, Thomas K. Hunt, Alfred Königsrainer, S. Beckert, M. Z. Hussain, and Q. P. Ghani
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Wound Healing ,Poly ADP ribose polymerase ,Clinical Biochemistry ,Down-Regulation ,General Medicine ,Fibroblasts ,Biology ,Nicotinamide adenine dinucleotide ,Biochemistry ,Molecular biology ,chemistry.chemical_compound ,medicine.anatomical_structure ,chemistry ,Apoptosis ,Cell culture ,Gene expression ,medicine ,Humans ,Lactic Acid ,NAD+ kinase ,Poly(ADP-ribose) Polymerases ,Fibroblast ,Wound healing ,Cells, Cultured ,Skin - Abstract
Background Polyadenosine diphosphate-ribose (poly(ADP-ribose)) is a nuclear polymer which is derived from nicotinamide adenine dinucleotide (NAD+) catalysed by poly(ADP-ribose) polymerase 1 (PARP-1). Aside from the well known role of poly(ADP-ribosyl)ation (pADPR) in DNA repair, pADPR is also involved in other cellular processes such as apoptosis and gene expression. However, the factors that regulate the level of pADPR are not fully elucidated. In view of the fact that healing wounds contain high concentrations of lactate (10–15 mm) and exogenous lactate reduce the NAD+ pool in cultured fibroblasts, we propose that high lactate lowers the level of nuclear pADPR. Materials and methods Neonatal human dermal fibroblasts (NHDF) were plated to subconfluence and allowed to adhere. Cells were treated with 15 mm l-lactate and pADPR production was assessed by immunofluorescence analysis using 10H antibody. Difference in pADPR production was determined by calculation of positively stained cells compared to total cell numbers. Inhibition of PARP activity was tested by treatment with 100 µm 3-aminobenzamide (3-AB). Specificity of the lactate effect on pADPR synthesis was verified by using the analogue d-lactate. The contents of nicotinamide adenine dinucleotide (NAD+) and its reduced form (NADH) in lactated and non-lactated cell cultures were quantified by the enzymatic cyclic assay. Results We found that exogenous l-lactate (15 mm) can significantly depress pADPR content in cultured fibroblasts. PARP-1 activity was inhibited by 3-AB and analogue d-lactate showed no effect on pADPR synthesis. NAD+/NADH ratio was significantly lowered in lactated compared to non-lactated cell culture. Conclusions Exogenous l-lactate (15 mm) can depress pADPR content in cultured fibroblasts. In view of the fact that healing wounds contain such high concentrations of lactate, we propose that down regulation of pADPR is associated with elevated tissue repair via pADPR dependent gene expression. This observation is important in understanding the stimulation of lactate-mediated protein expression during wound healing.
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- 2007
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36. [Untitled]
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Rashmi Chaudhary, Vinod Kumar, M. C. Jain, Shakeel A. Khan, Sudhir Kumar Sharma, Naveen Kalra, Himanshu Pathak, Sushil Kumar, H. C. Joshi, Ravindra Kumar, M. Z. Hussain, and R.C. Harit
- Subjects
Soil health ,General Medicine ,Management, Monitoring, Policy and Law ,Silt ,Pollution ,Bulk density ,Soil management ,Agronomy ,Loam ,Soil water ,Environmental science ,Transplanting ,Water content ,General Environmental Science - Abstract
Field experiments were carried out during 1996–97at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, NewDelhi and NCPP Campus, Dadri to evaluate changes in soilcharacteristics and growth of wheat (Triticum aestivum L.),mustard (Brassica juncea L.), lentil (Lence esculentaMoench.), rice (Oryza sativa L.) and maize (Zea mays L.) byvarying amounts of flyash addition (up to 50t ha-1) in soils atsowing/transplanting time of crops. Flyash addition in areasadjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P.ranged from 5–12 t ha-1 yr-1 in 1995–96. Shoot and root growthand yield of test crops at different locations after flyashincorporation resulted in beneficial effects of flyashaddition in most cases. The silt dominant texture of flyashimproved loamy sand to sandy loam textures of the surfacesoils at the farmers' fields. The increased growth in yield ofcrops with flyash incorporation was possibly due tomodifications in soil moisture retention and transmissioncharacteristics, bulk density, physico-chemical characterssuch as pH and EC and organic carbon content. The response offlyash addition in the soil on soil health and cropproductivity needs to be evaluated on long-term sustainableaspects.
- Published
- 2003
- Full Text
- View/download PDF
37. Improvement of tropical vegetation mapping using a remote sensing technique: A case of Khao Yai National Park, Thailand
- Author
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S. Murai, Rajendra P. Shrestha, M. Z. Hussain, Yongyut Trisurat, and A. Eiumnoh
- Subjects
Geography ,Thematic map ,Aerial photography ,Thematic Mapper ,National park ,Remote sensing (archaeology) ,Forest ecology ,Tropical vegetation ,medicine ,General Earth and Planetary Sciences ,medicine.symptom ,Vegetation (pathology) ,Remote sensing - Abstract
The forest ecosystems of Thailand are characterized by a diverse and complex vegetation structure. Classification of vegetation types of such forest ecosystems has been experienced as a difficult task, even with large-scale aerial photography. Satellite remote sensing, the digital technique in particular, has not been widely used for vegetation mapping in Thailand until now. The objective of this study was to explore the potential of digital image processing over the existing technique of visual interpretation of Landsat Thematic Mapper (TM) false colour composite (BGR-2, 3, 4) to produce forest cover maps in Thailand. Supervised and unsupervised classification methods were employed with different band combinations to discriminate vegetation types in the Khao Yai National Park using Landsat TM data. The results indicated that thematic classes derived from supervised classification produced higher overall accuracy than unsupervised classification. In addition, the combination of ratio bands R4/3, R5/2, R5/...
- Published
- 2000
- Full Text
- View/download PDF
38. Alterations of Fibroblast Metabolism in Early Ligature-Induced Periodontitis in the Cynomolgus Monkey
- Author
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B Enriquez, M Z Hussain, Q P Ghani, J C Zhang, C Hayashi, and M R Wirthlin
- Subjects
Poly Adenosine Diphosphate Ribose ,Pathology ,medicine.medical_specialty ,DNA Repair ,Biology ,Lesion ,Extracellular matrix ,chemistry.chemical_compound ,Gingivitis ,Transforming Growth Factor beta ,medicine ,Animals ,Periodontitis ,Fibroblast ,Ligation ,Cells, Cultured ,Superoxide ,Mesenchymal stem cell ,Proteins ,Fibroblasts ,medicine.disease ,Chronic periodontitis ,Disease Models, Animal ,Macaca fascicularis ,medicine.anatomical_structure ,chemistry ,Protein Biosynthesis ,Disease Progression ,Periodontics ,Female ,Collagen ,medicine.symptom ,Cell Division - Abstract
Cellular and biochemical observations were made of fibroblasts harvested from ligature-induced periodontitis and treated gingivitis areas in four adult female cynomolgus monkeys (Macaca fascicularis) to define the changes that occur in the early periodontitis lesion. Compared with fibroblasts from the treated sites, fibroblasts from the diseased areas had a significantly higher rate of proliferation, produced about two-thirds the amount of total protein and collagen, and failed to respond to TGF-beta, which normally stimulates extracellular matrix formation in mesenchymal cells. The diseased cells were also deficient in the activity of poly(ADP-ribose) synthetase, an enzyme involved in the repair of DNA breaks such as occur from the insults of superoxide and other active radicals present in inflamed areas. Although the precise nature of these biochemical defects is not fully elucidated, they may have an important bearing on chronic periodontitis cases with a "downhill" course.
- Published
- 1994
- Full Text
- View/download PDF
39. Injecting drug users in Bangladesh: prevalence of syphilis, hepatitis, HIV and HIV subtypes
- Author
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Akhil C. Banerjea, Abu S. M. M. Rahman, Mian M. M. Amin, J. Bogaerts, Abu M. Z. Hussain, Tasnim Azim, M S Sarker, Giasuddin Ahmed, and David L. Yirrell
- Subjects
Sexually transmitted disease ,Immunology ,HIV Infections ,Acquired immunodeficiency syndrome (AIDS) ,Prevalence ,medicine ,Humans ,Immunology and Allergy ,Syphilis ,Substance Abuse, Intravenous ,Sida ,Hepatitis ,Bangladesh ,biology ,business.industry ,fungi ,virus diseases ,Hepatitis C ,Hepatitis B ,medicine.disease ,biology.organism_classification ,Virology ,Needle-Exchange Programs ,Infectious Diseases ,Lentivirus ,HIV-1 ,business ,Viral hepatitis - Abstract
Injecting drug users (IDU) were enrolled from two detoxification clinics and two needle/syringe exchange programmes (NEP) in central and northwest Bangladesh. Syphilis, hepatitis C and HIV rates were highest in IDU from the NEP of central Bangladesh (23, 66.5 and 1.4%, respectively), whereas current hepatitis B infection rates were highest in IDU from the NEP of northwest Bangladesh (12%). Five HIV strains were subtype C and one E/B. The 32 base pair (bp) deletion of the CCR5 gene was not detected.
- Published
- 2002
- Full Text
- View/download PDF
40. Chest pain in children: an update
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M Z, Hussain, S, Ishrat, M, Salehuddin, M, Mahmood, and M T, Islam
- Subjects
Chest Pain ,Humans ,Child - Abstract
Chest pain is a common symptom for children and adolescents. It is the second most frequent complaint leading to referral to paediatric cardiologist, murmurs being the largest. The most common cause of chest pain prompting a child to visit a physician is idiopathic chest pain (21-59%). Other disorders are pulmonary (12-24%), psychologic (17-19%), musculoskeletal (7-16%), gastrointestinal (5-7%), cardiac (1-4%) and miscellaneous (2-4%). Most children with chest pain have normal physical findings. Careful physical examination can reveal important clues and save much unnecessary investigations. When an organic cause is found for the pain then specific treatment is commenced. Depending on the circumstances, a therapeutic trial may be warranted, for example use of an inhaled bronchodilator 15-20 minutes before exercise for suspected exercise induced asthma, use of adequate anti-reflux medication for gastro-oesophageal reflux disease or non-steroidal anti-inflammatory medication for musculoskeletal pain. Where an organic cause is not considered to be present, explanation and reassurance can reduce anxiety and decrease the severity of the symptoms. This article specifically deals with problems of chest pain in children and approach to such problems in the form of relevant investigations and management.
- Published
- 2011
41. Herbaceous layer development during spring does not deplete soil nitrogen in the Portuguese montado
- Author
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Margarete Wartinger, João Pereira, Heydar Mirzaei, Eun-Young Jung, Nuno Ribeiro, John Tenhunen, Dennis O. Otieno, Markus Schmidt, M. Z. Hussain, and Yanli Li
- Subjects
Biomass development of the herbaceous vegetation ,root distribution ,nutrient uptake ,Plant and soil nitrogen pools ,Pasture ,biomass development ,Nutrient ,Ecosystem ,Water content ,Ecology, Evolution, Behavior and Systematics ,Earth-Surface Processes ,geography ,geography.geographical_feature_category ,Ecology ,herbaceous vegetation ,Herbaceous plant ,Root distribution and nutrient uptake ,Portuguese montado ,Agronomy ,Soil water ,Mediterranean ecosystems ,Soil horizon ,Environmental science ,Soil moisture ,Cycling - Abstract
Available at ScienceDirect Nitrogen (N) content in the soil and in the herbaceous biomass were monitored during spring of 2004e2006 to determine how the herbaceous layer development influences soil N availability in the montado ecosystem of southern Portugal. Highest (246.6 52.7 g m 2) and lowest (123.2 89.5 g m 2) peak biomass occurred in 2006 and 2005 respectively. Total soilNwithin the top 20 cmsoil profile ranged between 0.2 0.1% in February and 0.41 0.2% inMay,while available soil N was lowest (5 2 mg g 1soil) in February but increased three-to-five fold in March and was >17.5 mg g 1soil at senescence in May. Significant (p < 0.001) increase in total N in the aboveground pool occurred between February and May. There was however, no decay in soil N content. Instead, the herbaceous vegetation enhanced soil N input and N retention in the ecosystem. Most of the herbaceous plants were annuals with large reserves of organic N at senescence, which returned to the soil as detritus. The herbaceous vegetation is a critical component of the montado that contributes to N recharge and cycling within the ecosystem
- Published
- 2010
42. Climate Change, Climate Variability and Indian Agriculture: Impacts Vulnerability and Adaptation Strategies
- Author
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Naveen Kalra, M. Z. Hussain, Shakeel A. Khan, and Sanjeev Kumar
- Subjects
Momentum (finance) ,Agriculture ,business.industry ,Natural resource economics ,Political economy of climate change ,Greenhouse gas ,Environmental resource management ,Vulnerability ,Biosphere ,Climate change ,Environmental science ,business ,Sea level - Abstract
Climate is changing naturally at its own pace, since the beginning of the evolution of earth, 4–5 billion years ago, but presently, it has gained momentum due to inadvertent anthropogenic disturbances. These changes may culminate in adverse impact on human health and the biosphere on which we depend. The multi-faceted interactions among the humans, microbes and the rest of the biosphere, have started reflecting an increase in the concentration of greenhouse gases (GHGs) i.e. CO2, CH4 and N2O, causing warming across the globe along with other cascading consequences in the form of shift in rainfall pattern, melting of ice, rise in sea level etc. The above multifarious interactions among atmospheric composition, climate change and human, plant and animal health need to be scrutinized and probable solutions to the undesirable changes may be sought.
- Published
- 2009
- Full Text
- View/download PDF
43. Laktat stimuliert die Migration von humanen Endothelzellen
- Author
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M. Z. Hussain, Heinz Scheuenstuhl, Stefan Beckert, Stephan Coerper, Rummana Aslam, and Alfred Königsrainer
- Subjects
Andrology ,Tissue culture ,Chemistry ,Protein biosynthesis ,Cell culture supernatant ,Biological activity ,Cell migration ,Chemotaxis ,Healing wounds ,Umbilical vein - Abstract
Introduction: Healing wounds are characterized by high lactate levels. Lactate has been shown to enhance collagen synthesis by fibroblasts and VEGF production by macrophages. However, little is known whether the increased VEGF level correlates with enhanced biological activity. Therefore, we investigated the migration of endothelial cells treated with lactate. Material and methods: Human umbilical vein endothelial cells (HUVEC) were cultured to subconfluent monolayers in standard 6 well tissue culture plates. Following a 16 hour serum starvation period, cells were treated with indicated concentrations of lactate for 20 hours in a standard incubator at 95% air and 10% CO2. Cellular migration was assessed using a modified Boyden-chamber. VEGF protein in the cell culture supernatant was measured by ELISA. All experiments were performed in triplicates and repeated at least twice. Results are given as mean ± SD; a p-value less than 0.05 calculated by Student’s t-test was considered significant. Results: Lactate enhanced VEGF protein synthesis in a time- and dose-dependent manner. Lactate added to the bottom well did not stimulate cellular migration from the upper well. However, lactate together with endothelial cells in the bottom well of the Boyden-Chamber increased cellular migration in a dose-dependent manner. This effect could be blocked both by anti-VEGF or cyclohexamide as well. Conclusion: Lactate enhances VEGF production in human endothelial cells. However, lactate is not a chemoattractant. Lactate mediated increase in cellular migration is regulated by VEGF.
- Published
- 2005
- Full Text
- View/download PDF
44. Soil properties and crop productivity as influenced by flyash incorporation in soil
- Author
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Naveen, Kalra, M C, Jain, H C, Joshi, R, Chaudhary, Sushil, Kumar, H, Pathak, S K, Sharma, Vinod, Kumar, Ravindra, Kumar, R C, Harit, S A, Khan, and M Z, Hussain
- Subjects
Soil ,India ,Agriculture ,Particulate Matter ,Plants, Edible ,Fertilizers ,Coal Ash ,Carbon - Abstract
Field experiments were carried out during 1996-97 at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, New Delhi and NCPP Campus, Dadri to evaluate changes in soil characteristics and growth of wheat (Triticum aestivum L.), mustard (Brassica juncea L.), lentil (Lence esculenta Moench.), rice (Oryza sativa L.) and maize (Zea mays L.) by varying amounts of flyash addition (up to 50t ha(-1)) in soils at sowing/transplanting time of crops. Flyash addition in areas adjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P. ranged from 5-12 t ha(-1)] yr(-1) in 1995-96. Shoot and root growth and yield of test crops at different locations after flyash incorporation resulted in beneficial effects of flyash addition in most cases. The silt dominant texture of flyash improved loamy sand to sandy loam textures of the surface soils at the farmers' fields. The increased growth in yield of crops with flyash incorporation was possibly due to modifications in soil moisture retention and transmission characteristics, bulk density, physico-chemical characters such as pH and EC and organic carbon content. The response of flyash addition in the soil on soil health and crop productivity needs to be evaluated on long-term sustainable aspects.
- Published
- 2003
45. Detection of interleukin-6 in human dental pulp and periapical lesions
- Author
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M. Z. Hussain, R. A. Barkhordar, and C. Hayashi
- Subjects
Adult ,Pathology ,medicine.medical_specialty ,biology ,business.industry ,Interleukin-6 ,medicine.medical_treatment ,Host response ,Pulpitis ,Inflammation ,Middle Aged ,Cytokine ,stomatognathic system ,medicine ,biology.protein ,Pulp (tooth) ,Humans ,Periapical Diseases ,Oral Surgery ,medicine.symptom ,business ,Interleukin 6 ,Periapical Periodontitis - Abstract
Pulpal and periapical diseases are characterized by inflammation. The cytokine IL-6 is a major mediator of the host response to tissue injury and infection. This study examined the level of interleukin-6 (IL-6) in six inflamed human pulps and six human periapical lesions of endodontic origin using ELISA. Pulp samples from eight clinically impacted teeth were used as controls. The periapical samples exhibited significant levels of IL-6 (mean = 78.1 +/- 9 pg/mg protein) as did inflamed pulpal tissues mean = 36 +/- 3.9 pg/mg protein) compared to healthy pulp mean = 0.01 +/- 0.02 pg/mg protein). These data indicated that IL-6 was produced and released locally in the inflamed pulpal and periapical lesions.
- Published
- 1999
46. Biochemical alterations in inflammatory periodontal diseases I. Poly (ADP-ribose) synthetase activity in gingiva and gingival fibroblasts from humans with periodontitis
- Author
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Gary C. Armitage, M Z Hussain, and Q P Ghani
- Subjects
Adult ,Male ,Poly Adenosine Diphosphate Ribose ,DNA Repair ,DNA repair ,Gingiva ,Inflammation ,Statistics, Nonparametric ,Microbiology ,Enzyme activator ,medicine ,Humans ,Fibroblast ,Periodontitis ,chemistry.chemical_classification ,biology ,Dental Plaque Index ,Fibroblasts ,Middle Aged ,medicine.disease ,Molecular biology ,Enzyme assay ,Enzyme Activation ,medicine.anatomical_structure ,Enzyme ,chemistry ,biology.protein ,Periodontics ,Specific activity ,Female ,medicine.symptom ,Periodontal Index ,Poly(ADP-ribose) Polymerases ,Reactive Oxygen Species - Abstract
Periodontal diseases are characterized in part by generation of oxygen free radicals, which can cause breaks in cellular DNA strands. Repair of damaged DNA is dependent upon the synthesis of poly (ADP-ribose)(PADPR) catalyzed by PADPR synthetase, an enzyme known to be activated by the broken ends of DNA strands. We measured the activities of PADPR synthetase and of PADPR glycohydrolase, which degrades PADPRS, in gingival biopsy specimens from 16 sites with adult periodontitis and 12 clinically healthy control sites. The results indicated that sites with periodontitis displayed markedly reduced PADPR synthetase activity compared with healthy control sites, whereas PADPR glycohydrolase activity was not changed. The mean specific activity of PADPR synthetase for the diseased specimens was one-sixth of that of the healthy specimens (p < 0.001). The PADPR synthetase activity was negatively correlated with the Gingival Index (rs = -0.60), pocket depth (rs = -0.70) and bleeding upon probing (rs = -0.72). Cultured fibroblasts derived from clinically characterized healthy and diseased gingival sites reflected similar patterns of enzyme activity. The mean specific activity of PADPR synthetase for the diseased-site cultures (n = 9) was 56 +/- 7% (p < 0.001) of the cultures from healthy control sites (n = 6). These results suggest that a reduced level of PADPR synthetase activity is associated with increased inflammation and periodontal destruction, and that the ability to synthesize PADPR is compromised in adult periodontitis.
- Published
- 1996
47. Lactate stimulation of macrophage-derived angiogenic activity is associated with inhibition of Poly(ADP-ribose) synthesis
- Author
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D D, Zabel, J J, Feng, H, Scheuenstuhl, T K, Hunt, and M Z, Hussain
- Subjects
Cornea ,Niacinamide ,Poly Adenosine Diphosphate Ribose ,Macrophages ,Lactates ,Animals ,Neovascularization, Physiologic ,Lactic Acid ,Rabbits ,NAD ,Oxidation-Reduction ,Cells, Cultured - Abstract
Injury and inflammation lead to hypoxia and elevated lactate in wounds. This redox environment establishes cells in a reparative phenotype and leads macrophages to release angiogenic substances by unclear mechanisms. We investigated compounds known to modulate polyadenosine diphophoribose (pADP-R) levels in their effect on macrophage-derived angiogenic activity. Macrophages cultured from rabbit bone marrow were exposed to lactate, nicotinamide, and/or beta-nicotinamide adenine dinucleotide (NAD+). Supernatants were assayed for angiogenesis, and macrophages were analyzed for NAD+ content, poly(ADP-ribose) synthetase activity, and total (ADP-ribose)n synthesis. Lactate-, nicotinamide-, and lactate and nicotinamide-treated macrophages elicited significantly increased angiogenic activity compared with control or NAD+-treated cells. Lactate treatment decreased NAD+ content by 42 +/- 4% and (ADP-ribose)n synthesis by 37 +/- 5%. Nicotinamide reduced poly(ADP-ribose) synthetase activity and poly(ADP-ribose) synthesis. Thus, macrophage-derived angiogenic activity may be mediated by the redox environment involving NAD+ metabolites.
- Published
- 1996
48. Decreased signal intensity of cerebral cortex on T2-weighted MR images
- Author
-
H, Oba, K, Ohtomo, T, Araki, G, Uchiyama, S, Monzawa, Y, Nogata, K, Kachi, M Z, Hussain, K, Koizumi, and Z, Shiozawa
- Subjects
Adult ,Aged, 80 and over ,Cerebral Cortex ,Male ,Aging ,Brain Diseases ,Adolescent ,Brain ,Middle Aged ,Magnetic Resonance Imaging ,Child, Preschool ,Humans ,Female ,Child ,Aged ,Retrospective Studies - Abstract
To define the frequency of decreased signal intensity (DSI) in cerebral cortex on T2-weighted images relative to aging and to the incidence of identifying white matter pathology, T2-weighted MR brain images of 906 patients consecutively examined between July 1989 and June 1991 were reviewed. MR images of cerebral cortex were divided into five areas: frontal lobe (F), pre- and postcentral gyri (C), parietal lobe (P), occipital lobe (O) and temporal lobe (T). Each area was separately and independently evaluated for the presence or absence of DSI. The frequency of DSI in each area was plotted against patients' ages. The severity of leukoaraiosis was evaluated in relation with DSI in each cortical area. Patients with DSI in area F numbered 61 (5.7%), in area C 236 (26.0%), in area P 174 (15.9%), in area O 428 (47.2%), and in area T 10 (1.1%). The number of patients with DSI in each area increased with age. The greater the severity of leukoaraiosis, the greater the chance of finding DSI of the cerebral cortex. The incidence of DSI in the cerebral cortex increased with the patient's age as well as with the severity of co-existent white matter pathology.
- Published
- 1996
49. Blood pressure and glycemic status in relation to body mass index in a rural population of Bangladesh
- Author
-
M A, Sayeed, A R, Khan, A, Banu, M Z, Hussain, and S M, Ali
- Subjects
Adult ,Blood Glucose ,Male ,Bangladesh ,Adolescent ,Blood Pressure ,Rural Health ,Middle Aged ,Body Mass Index ,Hypertension ,Diabetes Mellitus ,Prevalence ,Humans ,Female - Abstract
A cluster sampling of five villages in Dohar thana were selected for screening of hypertension and diabetes in relation to age structure and body habitus. All the subjects over 15 years of age were enlisted for investigation. The response rate was more than 70%. Height, weight, blood pressure (BP) and capillary blood glucose (fasting and 2-hPG) were measured. Diagnostic criteria of international standard were used for hypertension and diabetes. Out of 1005 participants 106 subjects (10.5%) had systolic blood pressure (sBP) more than 140 mmHg and 9% of them had diastolic blood pressure (dBP) more than 90 mmHg. The prevalence of non-insulin-dependent diabetes mellitus (NIDDM) was 2.1% and impaired glucose tolerance (IGT) was 13.3%. The mean body mass index (BMI) of men was 20.39 (SD = 2.91) and that of women was 20.11 (SD = 2.92), having no significant difference between them. Increased age (or = 50 yr), high BMI (or = 23.0) and hyperglycemia (2-hPG7.8 mmol/L) were the risk factors for both systolic (sBP140 mmHg) and diastolic (dBP90 mmHg) hypertension. Likewise, increased age, high BMI and hypertension showed significant association with glucose intolerance. Moreover, significant correlations were observed between age and BP (sBP, r = 0.328 p0.001; dBP, r = 0.187 p0.001) BMI and BP (sBP, r = 0.193 p0.001; dBP, r = 0.192 p0.001) and 2-hPG and BP (sBP, r = 0.188 p0.001; dBP, r = 0.134 p0.001).
- Published
- 1994
50. A study of chondroitin sulfate iron colloid as a liver specific MR contrast agent
- Author
-
M Z, Hussain, K, Ohtomo, K, Kachi, G, Uchiyama, and Y, Itai
- Subjects
Carcinoma, Hepatocellular ,Time Factors ,Iron ,Chondroitin Sulfates ,Liver Neoplasms ,Contrast Media ,Adenocarcinoma ,Image Enhancement ,Magnetic Resonance Imaging ,Rats ,Liver ,Image Processing, Computer-Assisted ,Animals ,Colloids - Abstract
Chondroitin sulfate iron colloid (CSIC) is a therapeutic agent for iron deficiency anemia. The potential of CSIC to decrease liver signal intensity at magnetic resonance (MR) imaging has already been tested. Enhanced detection of liver carcinoma by CSIC at MR imaging was studied in vivo. Our purpose was to determine the time period required to obtain the maximum contrast enhancement from CSIC at different dose levels. We performed MR imaging of eight rats with hepatic carcinoma before and after CSIC administration. For all dose groups it was found that on T2-weighted images the maximum contrast to noise ratio (C/N) was at 4-8 hours after the drug administration, while on proton density-weighted images the maximum C/N was at 2-8 hours.
- Published
- 1994
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