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Background: Perfusion imaging, one of MRI’s techniques, is widely used to test damaged tissues of the body. The parameters used in this technique include cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT). The MRI scanner contains a device called a “phantom”, which controls the accuracy of various imaging models. Objective: Our goal is to design and produce a microphantom to control the perfusion-imaging model in MRI scanners.Material and Methods: Firstly, in an analytical study type, we designed the phantom based on Murray’s minimum work rule using AutoCAD software. Next, the phantom was fabricated using lithography and then imaged using a Siemens Magnetom 3T Prisma MRI scanner at the National Brain Laboratory. Finally, the velocity and pressure in the capillary network was simulated using COMSOL software. Results: CBF, CBV, and MTT curves for the capillary network were obtained at different times. In addition, the simulations showed that the velocity and pressure in the capillary network were between 0.0001 and 0.0005 m/s and between 5 and 25 mm/Hg, respectively. Conclusion: The fabricated microphantom was used to simulate the movement of blood within tissues of the body. Different parameters of perfusion imaging were measured inside the phantom, and they in the phantom were similar to in the body.

Abstract Due to extensive root system, connected rhizome bamboos are considered suitable for improving soil properties within a short period, though most of the claims are anecdotal and need to be supported with quantified data. The study evaluates seven bamboo species viz., Bambusa balcooa, Bambusa bambos, Bambusa vulgaris, Bambusa nutans, Dendrocalamus hamiltonii, Dendrocalamus stocksii and Dendrocalamus strictus for their rooting pattern and impact on soil health properties. Coarse and fine root intensity was maximum in B. vulgaris. Coarse root biomass ranged from 0.6 kg m−3 in B. nutans to 2.0 kg m−3 in B. vulgaris and B. bambos. Fine root biomass ranged from 1.1 kg m−3 in B. nutans to 4.5 kg m−3 in D. hamiltonii. Contribution of fine roots in terms of intensity and biomass was much higher than coarse roots. Fine root biomass showed declining trend with increase in soil depth in all the species. During sixth year, the litter fall ranged from 8.1 Mg ha−1 in D. stocksii to 12.4 Mg ha−1 in D. hamiltonii. Among soil physical properties significant improvement were recorded in hydraulic conductivity, water stable aggregates and mean weight diameter. Soil pH, organic carbon and available phosphorus under different species did not reveal any significant changes, while significant reduction was observed in total nitrogen and potassium. Significant positive correlation was observed between WSA and iron content. Soil microbial population and enzyme activities were higher in control plot. Considering root distribution, biomass, soil hydraulic conductivity and water stable aggregates, B. bambos, B. vulgaris and D. hamiltonii are recommended for rehabilitation of degraded lands prone to soil erosion.

Age-related visual decline and disease due to neural dysfunction are major sources of disability that have resisted effective treatment. In light of evidence that visual impairment and mitochondrial dysfunction advance with age, we characterized age-related decline of spatial visual function in mice and investigated whether treatment of aged mice with the mitochondrion-penetrating peptide elamipretide that has been reported to improve mitochondrial function, would improve it. Impaired photopic acuity measured by using a virtual optokinetic system emerged near 18 months and declined to ∼40% below normal by 34 months. Daily application of the synthetic peptide elamipretide, which has high selectivity for mitochondrial membranes that contain cardiolipin and promotes efficient electron transfer, was able to mitigate visual decline from 18 months onwards. Daily application from 24 months onwards, i.e. when acuity had reduced by ∼16%, reversed visual decline and normalized function within 2 months. Recovered function persisted for at least 3 months after treatment was withdrawn and a single treatment at 24 months delayed subsequent visual decline. Elamipretide applied daily from 32 months onwards took longer to take effect, but substantial improvement was found within 2 months. The effects of age and elamipretide treatment on contrast sensitivity were similar to those on acuity, systemic and eye drop applications of elamipretide had comparable effects, scotopic spatial visual function was largely unaffected by age or treatment, and altered function was independent of variation in optical clarity. These data indicate that elamipretide treatment adaptively alters the aging visual system. They also provide a rationale to investigate whether mitochondrial dysfunction is a treatable pathophysiology of human visual aging and age-related visual disease.

Modelling and mapping of weekly rainfall was carried out for NW Himalayan states of India for kharif crop planning. Based on the findings of the study it was observed that, J&K states with area coverage of 2.7 m ha witnessed maximum rainy days at 25 SMW indicating 1st week of July as optimum sowing time for kharif crops, whereas in HP, 26th SMW, i.e. 2nd week of July was maximum considering both rainfall amount and rainy days with 0.54 m ha area coverage. But, in case of Uttarakhand, it differs widely which ranges from 26-28 SMW for rainfall and 30-31 SMW for rainy days category in 0.68 m ha area. The spatial-temporal maps of rainfall distribution will help in site-specific decision making for entire kharif crop planning adjusted to different landforms.

Background: Glucose transporter (Glut), a cellular transmembrane receptor, has a key role in the metabolism of cell glucose and is also associated with various human carcinomas.Objective: In this study, we evaluated a magnetic resonance (MR) imaging contrast agent for tumor detection based on paramagnetic gadolinium oxide (Gd2O3) coated polycyclodextrin (PCD) and modified with glucose (Gd2O3@PCD-Glu) for the targeting of overexpressed glucose receptors.Material and Methods: In this experimental study, 3T magnetic resonance imaging (MRI) scanner was used to assess the specific interactions between Glut1-overexpressing tumor cells (MDA-MB-231) and Gd2O3@PCD-Glu NPs. Furthermore, the capacity of transporting Gd2O3@PCD-Glu NPs to tumor cells was evaluated. Results: It was found that the acquired MRI T1 signal intensity of MDA-MB-231 cells that were treated with the Gd2O3@PCD-Glu NPs increased significantly. Based on the results obtained, Gd2O3@PCD-Glu NPs can be applied in targeting Glut1-overexpressing tumor cells in vivo, as well as an MRI-targeted tumor agent to enhance tumor diagnosis. Conclusion: Results have shown that glucose-shell of magnetic nanoparticles has a key role in diagnosing cancer cells of high metabolic activity.

The present study explores the possibility of developing statistical models for prediction of dry fibre yield of tossa jute (Corchorus olitorius) in India. Sixty plants of 110 days age were randomly selected from the study area, and their basal diameter and dry fibre yield were measured for analysis and fitting of models. Basal diameter was found to be a very good predictor of dry fibre yield and was included in the model. Various functions (linear, monomolecular, logistic, Gompertz, allometric, Chapman) were fitted to estimate a relationship between dry fibre yield and basal diameter of the plant. The adjusted R2 values were > 0.72 for all six models and Chapman model (Y = k × (1-exp (-a×X))b was found as best performing with highest R2 (0.77) lowest Akaike's information criterion (AIC) value (68.40) . The paired t statistics value between observed and predicted fibre yield was found non-significant (p>0.05), which clearly indicates the validity of the model. The models developed in the present study will be of immense help to the jute cultivators in estimating dry fibre yield before harvesting, by simply measuring the basal diameter values of the jute plants. The estimated fibre yield is 34 q/ha with average basal diameter of 1.3 cm and 4 lakh/ha plant density.

Introduction: Electrical impedance of tissues on low frequencies includes useful information about functional and structural changes in tissues. This property is used in Electrical Impedance Tomography (EIT) imaging modality for the detection of lesions in tissues. Objective: The goal of this article is to study changes in electrical impedance of tissues in the presence of gold nanoparticles. Materials and Methods: Spherical gold nanoparticles with size of 20-25 nm were synthesized with Turkevich method. Size distribution and shape of nanoparticles were characterized by transmission electron microscopy (TEM). Electrical impedance of two types of phantoms (chicken fat and muscle paste tissues) was measured by 4-electrode method with and without gold nanoparticles. Results: Results demonstrate a reduction in electrical impedance of tissues in the presence of gold nanoparticles. However, this reduction is not the same for fat and muscle tissues. Reductions in resistive impedance are for fat and muscle tissues on the frequency of 1 KHz, respectively. A reduction in electrical impedance is accompanied by a rise in electrical conductance leading to increase in EIT signal. Conclusion: As signal enhancement is different for fat and muscle tissues; presence of gold nanoparticles could be used to improve EIT image contrast.

In this study we investigated the chemical constituents of bioactive methanol extract of Euphorbia schimperi C. Presl. For this the methanol extract was fractionated into 20, 40, 60, 80% MeOH in CHCl3, and 100% MeOH fractions respectively by vacuum liquid chromatography. Excision wound surface of the animals were topically treated with these fractions at a dose of 100 mg/kg body weight for twenty days. Povidone-iodine ointment was used as a reference drug. Wound contraction measurement and period of epithelialization were used to assess the effect of fractions on wound repairing. The 100% MeOH fraction treated animals achieved significant (p < 0.001) value by showing 100% wound contraction and minimum period of epithelization (17.75±0.47) on the 20th day as compared to standard drug treated animals on the same day. The active 100% MeOH fraction was subjected to various chromatographic techniques led to the isolation of miquelianin (1), kaempferol 3-O-glucuronide (2) and quercitrin (3). Compounds (1-3) were isolated from this plant for the first time.

Although intensive agriculture is necessary to sustain the world's growing population, accelerated soil erosion contributes to a decrease in the environmental health of ecosystems at local, regional and global scales. Reversing the process of land degradation using vegetative measures is of utmost importance in such ecosystems. The present study critically analyzes the effect of grasses in reversing the process of land degradation using a systematic review. The collected information was segregated under three different land use and land management situations. Meta-analysis was applied to test the hypothesis that the use of grasses reduces runoff and soil erosion. The effect of grasses was deduced for grass strip and in combination with physical structures. Similarly, the effects of grasses were analyzed in degraded pasture lands. The overall result of the meta-analysis showed that infiltration capacity increased approximately 2-fold after planting grasses across the slopes in agricultural fields. Grazing land management through a cut-and-carry system increased conservation efficiencies by 42 and 63 % with respect to reduction in runoff and erosion, respectively. Considering the comprehensive performance index (CPI), it has been observed that hybrid Napier (Pennisetum purpureum) and sambuta (Saccharum munja) grass seem to posses the most desirable attributes as an effective grass barrier for the western Himalayas and Eastern Ghats, while natural grass (Dichanthium annulatum) and broom grass (Thysanolaena maxima) are found to be most promising grass species for the Konkan region of the Western Ghats and the northeastern Himalayan region, respectively. In addition to these benefits, it was also observed that soil carbon loss can be reduced by 83 % with the use of grasses. Overall, efficacy for erosion control of various grasses was more than 60 %; hence, their selection should be based on the production potential of these grasses under given edaphic and agro-ecological conditions. The present analysis also indicated that grass must be used as a vegetative strip to maintain soil quality in sloppy arable areas (8.5 Mha) of Indian hilly regions. Similarly, due attention should be paid for establishing grasses in 3 Mha of degraded pasture lands and 3.5 Mha of shifting cultivation areas in India to reverse the land degradation.

Concept of the paper is firstly to remove the trend of crop yield and then to develop the forecasting models using detrended yield. Not much work is available or development of forecast models or modelling due to their non-linear behaviour. For that, in this paper, methodology developed for forecasting using nonlinear growth models, which will help in forecasting yield, pest and disease incidences etc with high accuracy. Crop yield forecast models for wheat crop have been developed (using non-linear growth models, linear models and weather indices approach with weekly weather data) for different districts of Uttar Pradesh (UP). Weather Indices (WI) were obtained using above two approaches. Weather indices based regression models were developed using weather indices as independent variables while character under study such as crop yield was used as dependent variable for wheat crop, i.e. two step non-linear forecast model. Technique of forecasting using non-linear approach and using weather indices will enrich the knowledge in developing customized models on forecasting for different types of crops and for different locations. The approach provided reliable yield forecast about two months before harvest.

IntroducationIn a recent Cochrane review the authors concluded that there is an urgent need for well-powered, well-conducted randomized controlled trials comparing various modes of treatment of fistula-in-ano. Ten randomized controlled trials were available for analyses: There were no significant differences in recurrence rates or incontinuence rates in any of the studied comparisons. The following article reviews all studies available for treatment of fistula-in-ano with a fistula plug.Material and MethodsPubMed, Medline, Embase and the Cochrane medical database were searched up to December 2014. 47 articles were relevant for this review.ResultsHealing rates of 50 – 60 % can be expected for treatment of complex anal fistula with a fistula plug, with a plug-extrusion rate of 10 – 20 %. Such results can be achieved not only with plugs made of porcine intestinal submucosa, but also those made of other biological mesh materials, such as acellular dermal matrix. Important technical steps in the performance of a complex anal fistula plug repair need to be followed.SummaryTreatment of a complex fistula-in-ano with a fistula plug is an option with a success rate of 50 – 60 % with low complication rate. Further improvements in technique and better studies

Introduction: Image distortion is one of the major problems of magnetic resonance imaging (MRI) for use in 3DMRI, velocity MRI, FMRI and radiotherapy treatment planning (RTTP). It is widely known that the most obvious effect of the inhomogenity of the magnetic fields and the nonlinearity of the gradient is the Geometric Distortion of MR tomograms. In this study, the accuracy of MR images was considered by the phantom study and the reproducibility of images was evaluated by repeating the phantom measurements. Materials and Methods: MRI scans of the phantom with grid pattern inside it were performed using head coil in two 1.5 Tesla MRI systems (Picker VISTA TM HPQ, USA & GE Signa Echo Speed, USA). For the Geometric Distortion reproducibility evaluation the T1W, T2W and PDW SE protocols were repeated three times. The Geometric Distortion was measured by an edge detection program in MATLAB. Results: The geometric distortion in the peripheral area of the images tends to be generally larger than it in the central area in all images. The average displacement in Picker MRI was 3 pixels in the y and 1 pixel in the x direction and in GE MRI it was 1 pixel in both x and y direction for 24 cm FOV (pixel = 0.9 mm). Discussion and Conclusions: Since the positional variation was within 1 to 3 pixels for the head coil, it will be possible to use this MR system in 3DMRI, velocity MRI, FMRI and RTTP. To decrease the geometric distortion the use of suitable coil and protocol are expected.

In the present study, standardized precipitation index (SPI) series at 3-month, 6-month, 9-month, 12-month and 24month time scale has been used to assess the vulnerability of meteorological drought in the Bundelkhand region of Central India. SPI values revealed that the droughts in the region over the study period vary from moderately high to extremely high. Suitable linear stochastic model, viz. seasonal and non-seasonal autoregressive integrated moving average (ARIMA) developed to predict drought at different time scale. The best model was selected based on minimum Akaike Information Criterion (AIC) and Schwarz Bayesian Criterion (SBC). Statistical analysis revealed that non-seasonal ARIMA model was appropriate for 3-month SPI series while seasonal ARIMA models have been found promising for SPI series at 6-, 9,12 and 24-month time scale. Parameter estimation step indicates that the estimated model parameters are significantly different from zero. The predicted data using the best ARIMA model were compared to the observed data for model validation purpose in which the predicted data show reasonably good agreement with the actual data. Hence the models were applied to forecast drought in the Bundelhand region up to 3 months advanced with good accuracy.

Background and purpose: Selection of suitable parameters for brain MRA requires accurate measures, because the image quality depends on the location of arteries, veins and also the velocity differences of blood, taking into account the low blood flow in small veins and arteries, use of paramagnetic contrast media is recommended. Hence, in present study, we investigated the imaging optimization of brain vessels using contrast media in 1.5 T field.Materials and Methods: For image optimization blood T1 was estimated after the injection of 0.1mmol/kg of Gd-DTPA and the relative blood signals were measured at T1=300, 600, 900 and 1200ms using TR=20ms and TE=7ms parameters. Ernest angle and relative signal increased as the T1 decreased. MRA was obtained in three groups, each including five volunteer patients using parameters TR=20ms, TE=7ms and flip angle 10, 20 & 30 degrees in two series without and during contrast injection.Signals of carotid, M.C.A and thorcolar herofili and SD in air were measured and it was shown that in 20 degrees flip angle, C/N was maximum.At the last stage, three series of MRA, without, during c.i and 15 minutes after c.i where obtained in 20 volunteer patients using parameters TR=20ms, TE=7ms and flip angle 20 degrees and calculated C/N .Results: After statistical analysis the highest C/N was observed during c.i MRA. Paired t-student test was performed to compare the differences between the C/N ratios. For clinical purposes one vein and two arterles were graded in 5 definite levels.Conclusion: Results indicated an important effect of paramagnetic contrast media on better observing of small arteries and vein. The best quality was taken during c.i, but in some arteries contrast media did not improve the quality of MRA.

Background: Perfusion imaging, one of MRI's techniques, is widely used to test damaged tissues of the body. The parameters used in this technique include cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT). The MRI scanner contains a device called a "phantom", which controls the accuracy of various imaging models. Objective: Our goal is to design and produce a microphantom to control the perfusion-imaging model in MRI scanners. Material and Methods: Firstly, in an analytical study type, we designed the phantom based on Murray's minimum work rule using AutoCAD software. Next, the phantom was fabricated using lithography and then imaged using a Siemens Magnetom 3T Prisma MRI scanner at the National Brain Laboratory. Finally, the velocity and pressure in the capillary network was simulated using COMSOL software. Results: CBF, CBV, and MTT curves for the capillary network were obtained at different times. In addition, the simulations showed that the velocity and pressure in the capillary network were between 0.0001 and 0.0005 m/s and between 5 and 25 mm/Hg, respectively. Conclusion: The fabricated microphantom was used to simulate the movement of blood within tissues of the body. Different parameters of perfusion imaging were measured inside the phantom, and they in the phantom were similar to in the body. [ABSTRACT FROM AUTHOR]

Background: Numerous unique characteristics of the nanosized gold, including high atomic number, low toxicity, and high biocompatibility make it one of the most appropriate nanostructures to boost radiotherapy efficacy. Many in-vivo and in-vitro investigations have indicated that gold nanoparticles (AuNPs) can significantly increase tumor injuries in low kilovoltage radiotherapy. While deep-lying tumors require much higher energy levels with greater penetration power, and investigations carried out in megavoltage energy range show contradictory results. Objective: In this study, we quantitatively assess and compare dose enhancement factors (DEFs) obtained through AuNPs under radiation of Cobalt-60 source (1.25MeV) versus Iridium-192 source (380 KeV) using MAGAT gel dosimeter. Material and Methods: MAGAT polymer gel in both pure and combined with 0.2 mM AuNPs was synthesized. In order to quantify the effect of energy on DEF, irradiation was carried out by Co-60 external radiotherapy and Ir-192 internal radiotherapy. Finally, readings of irradiated and non-irradiated gels were performed by MR imaging. Results: The radiation-induced R2 (1/T2) changes of the gel tubes doped with AuNPs compared to control samples, upon irradiation of beams released by Ir-192 source showed a significant dose enhancement (15.31% ±0.30) relative to the Co-60 external radiotherapy (5.85% ±0.14). Conclusion: This preliminary study suggests the feasibility of using AuNPs in radiation therapy (RT), especially in low-energy sources of brachytherapy. In addition, MAGAT polymer gel, as a powerful dosimeter, could be used for 3D visualization of radiation dose distribution of AuNPs in radiotherapy. [ABSTRACT FROM AUTHOR]

Management of severely malnourished children with associated complications relies on hospital-based treatment. Implementation of a standardized protocol at the Dhaka Hospital, ICDDR,B reduced case fatality approximately 50%. We developed and prospectively evaluated a day-care clinic approach that provided antibiotics, micronutrients and feeding during the day with continued care by parents at home at night as an alternative to hospitalization. Severely malnourished children aged 6–23 months denied admission to hospital were enrolled at Radda Clinic, Dhaka and received protocolized management with antibiotics, micronutrients and milk-based diet from 8:00 am to 5:00?pm each day, while mothers were educated on continuation of care at home. They were transitioned to the day-care nutrition rehabilitation (NR) unit of Radda Clinic following resolution of acute illness, received NR diet (Khichuri, halwa and milk-based) daily until children attained 80% weight-for-length. From February 2001 to November 2003, 264 children were enrolled; 52% were boys and 78%, 21% and 1% had marasmus, marasmus–kwashiorkor and kwashiorkor, respectively. Only 13% had severe malnutrition alone while 35% had pneumonia, 35% had diarrhea and 17% had both pneumonia and diarrhea. The mean (SD) duration of acute and NR phases were 8 (4) and 14 (13) days, respectively. Children gained weight [mean (SD) g/kg day] more rapidly during acute 10 (7) than NR phase 6 (5). Successful management was possible in 82% (95% CI 77–86%) children, 12% discontinued treatment and 6% referred to hospitals. Only one child died during NR phase. Severely malnourished children can be successfully managed at existing day-care clinics using a protocolized approach. [ABSTRACT FROM AUTHOR]