755 results on '"Patel, N. A."'
Search Results
52. Patterns of online information use prior to middle-ear surgery: a retrospective cohort study.
- Author
-
Lodhia, C, Jufas, N, and Patel, N
- Subjects
- *
MIDDLE ear surgery , *ELECTIVE surgery , *MULTIMEDIA systems , *INTERNET , *SOCIAL media , *RETROSPECTIVE studies , *SCREEN time , *SURVEYS , *INFORMATION retrieval , *INFORMATION resources , *HEALTH , *ACCESS to information , *LONGITUDINAL method , *WORLD Wide Web , *DIGITAL diagnostic imaging - Abstract
Objective: This study aimed to identify what proportion of middle-ear surgery patients utilise the internet for information and to characterise which resources and media formats are used and for what durations. Method: A single-arm, retrospective cohort study was performed using an online survey of English-speaking patients who underwent middle-ear surgery over a three-year period across two otology practices. Results: Of 260 invitees, 165 responded. A total of 122 used online resources: 9.8 per cent used online resources for less than 15 minutes, 27.0 per cent used them for 15 to 29 minutes, 27.0 per cent used them for 30 to 59 minutes and 36.1 per cent used them for 60 minutes or more. Of online users with complete responses (108 of 122), the most used resources (used for 12 minutes or more) were: written information (73.1 per cent); surgeons' websites (55.6 per cent); pictures, diagrams or photos (42.6 per cent); videos (37.0 per cent); and social media (10.2 per cent). Conclusion: At least 46.9 per cent of patients undergoing elective ear surgery use online resources. Most time is spent using written information, pictures, diagrams, photos and videos. Therefore, it is increasingly essential that accurate and informative resources in these formats are readily available online. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
53. Correlation and path analysis in brinjal (Solanum melongena L.) for yield and yield related traits.
- Author
-
Chetan, Gal, Pandya, M. M., Patel, N. A., Joshi, Rutvik J., and Desai, Bhavya
- Subjects
- *
EGGPLANT , *PATH analysis (Statistics) , *STATISTICAL correlation , *FRUIT yield , *PLANT yields , *GENOTYPES - Abstract
Sixty different varieties of brinjal (Solanum melongena L.) were evaluated for character association. The findings showed that the genotypic correlation was higher than the phenotypic correlation coefficient for most traits. Strong positive correlation was observed between the number of fruits per plant, branches per plant, and fruit yield per plant. Positive correlation was observed between moisture content and fruit characteristics, such as fruit volume and average fruit weight. The path coefficient analysis revealed that high positive direct effect on fruit yield was exerted by fruits per plant, followed by moisture content. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
54. Attitudes and barriers to participation in window-of-opportunity trials reported by White and Asian/Asian British ethnicity patients who have undergone treatment for endometrial cancer.
- Author
-
Mandane, B., Amirthanayagam, A., Patel, N., Darko, N., and Moss, E. L.
- Subjects
- *
ETHNICITY , *ENDOMETRIAL cancer , *CRIME & the press , *ATTITUDE (Psychology) , *MINORITIES , *PARTICIPATION , *VITAMINS - Abstract
Purpose: Window-of-opportunity trials (WOT) are a study design that have been used to investigate drug activity in endometrial cancer (EC). Recruitment to cancer clinical trials by patients from ethnic minority groups is reported to be lower than for patients of White ethnicity. Methods: A verbal questionnaire was conducted with White and Asian/Asian British ethnicity patients who had undergone treatment for EC. Strategic purposeful sampling was used to recruit patients from diverse social/educational backgrounds. Questions explored: background knowledge of clinical research, WOT study design, and views on medications that might be investigated. Thematic analysis was used to explore motivations for WOT participation and perceived barriers. Results: In total, 21 patients were recruited to the study (15 White and 6 Asian/Asian British). Views on optimum time to receive trial information differed, preferences ranging from 'at the time of diagnosis' to 'a few days after diagnosis'. The choice of medication under investigation had a strong influence on potential willingness to participate, with greater interest reported in medications derived from vitamins or food supplements rather than hormone-based drugs. Potential barriers to participation included concern over potential side-effects and the emotional/physical burden of a cancer diagnosis prior to major surgery. Discussion: This study provides important insights into patients' views on WOT participation in EC and raises issues that need to be considered for future trial design and participant recruitment materials. The timing and format of study information and type of substance under investigation were factors influencing potential participation. Future studies should consider using multi-lingual visual information videos to address information needs, as this may encourage participation by ethnic minority patients. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
55. Athena: Specialty Certificate Examination case for outpatient medical dermatology.
- Author
-
Hussain, K. and Patel, N. P.
- Subjects
- *
IRRITABLE colon , *DERMATOLOGY , *LEUKOCYTE count - Abstract
Int J Dermatol 2020; 59: 221 - 8. 3 Petryszyn P, Staniak A, Wolosianska A, Ekk-Cierniakowski P. Faecal calprotectin as a diagnostic marker of inflammatory bowel disease in patients with gastrointestinal symptoms: meta-analysis. A 20-year-old black woman presents to clinic with a 2-year history of recurrent nodules and abscesses affecting her groins and axillae. Option (a) is not required in our patient but is performed in patients with fistulating perianal and genital disease to assess the anatomy of the sinus tracts. [Extracted from the article]
- Published
- 2022
- Full Text
- View/download PDF
56. Genetic investigation of 93 families with microphthalmia or posterior microphthalmos.
- Author
-
Patel, N., Khan, A. O., Alsahli, S., Abdel‐Salam, G., Nowilaty, S. R., Mansour, A. M., Nabil, A., Al‐Owain, M., Sogati, S., Salih, M. A., Kamal, A. M., Alsharif, H., Alsaif, H. S., Alzahrani, S. S., Abdulwahab, F., Ibrahim, N., Hashem, M., Faquih, T., Shah, Z. A., and Abouelhoda, M.
- Subjects
- *
MICROPHTHALMIA , *SINGLE nucleotide polymorphisms , *NUCLEOTIDE sequencing , *EYE diseases , *MICROPHTHALMIA-associated transcription factor - Abstract
Microphthalmia is a developmental eye defect that is highly variable in severity and in its potential for systemic association. Despite the discovery of many disease genes in microphthalmia, at least 50% of patients remain undiagnosed genetically. Here, we describe a cohort of 147 patients (93 families) from our highly consanguineous population with various forms of microphthalmia (including the distinct entity of posterior microphthalmos) that were investigated using a next‐generation sequencing multi‐gene panel (i‐panel) as well as whole exome sequencing and molecular karyotyping. A potentially causal mutation was identified in the majority of the cohort with microphthalmia (61%) and posterior microphthalmos (82%). The identified mutations (55 point mutations, 15 of which are novel) spanned 24 known disease genes, some of which have not or only very rarely been linked to microphthalmia (
PAX6, SLC18A2, DSC3 andCNKSR1 ). Our study has also identified interesting candidate variants in 2 genes that have not been linked to human diseases (MYO10 andZNF219 ), which we present here as novel candidates for microphthalmia. In addition to revealing novel phenotypic aspects of microphthalmia, this study expands its allelic and locus heterogeneity and highlights the need for expanded testing of patients with this condition. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
57. Development of a selective androgen receptor modulator for transdermal use in hypogonadal patients.
- Author
-
Krishnan, V., Patel, N. J., Mackrell, J. G., Sweetana, S. A., Bullock, H., Ma, Y. L., Waterhouse, T. H., Yaden, B. C., Henck, J., Zeng, Q. Q., Gavardinas, K., Jadhav, P., Saeed, A., Garcia‐Losada, P., Robins, D. A., and Benson, C. T.
- Subjects
- *
ANDROGEN receptors , *HYPOGONADISM , *SKELETAL muscle , *SKIN absorption , *DRUG side effects , *PATIENTS - Abstract
Summary: We have identified a non‐steroidal selective androgen receptor modulator (SARM), termed LY305, that is bioavailable through a transdermal route of administration while highly cleared via hepatic metabolism to limit parent compound exposure in the liver. Selection of this compound and its transdermal formulation was based on the optimization of skin absorption properties using both in vitro and in vivo skin models that supported PBPK modeling for human PK predictions. This molecule is an agonist in perineal muscle while being a weak partial agonist in the androgenic tissues such as prostate. When LY305 was tested in animal models of skeletal atrophy it restored the skeletal muscle mass through accelerated repair. In a bone fracture model, LY305 remained osteoprotective in the regenerating tissue and void of deleterious effects. Finally, in a small cohort of healthy volunteers, we assessed the safety and tolerability of LY305 when administered transdermally. LY305 showed a dose‐dependent increase in serum exposure and was well tolerated with minimal adverse effects. Notably, there were no statistically significant changes to hematocrit or HDL after 4‐week treatment period. Collectively, LY305 represents a first of its kind de novo development of a non‐steroidal transdermal SARM with unique properties which could find clinical utility in hypogonadal men. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
58. Estimating net primary productivity of croplands in Indo-Gangetic Plains using GOME-2 sun-induced fluorescence and MODIS NDVI.
- Author
-
Patel, N. R., Padalia, Hitendra, Devadas, R., Huete, A., Kumar, A. Senthil, and Krishna Murthy, Y. V. N.
- Subjects
- *
FLUORESCENCE spectroscopy , *PRIMARY productivity (Biology) measurement , *NORMALIZED difference vegetation index , *AGRICULTURAL productivity - Abstract
Recently evolved satellite-based sun-induced fluorescence (SIF) spectroscopy is considered as a direct measure of photosynthetic activity of vegetation. We have used monthly averages of satellite-based SIF retrievals for three agricultural year cycles, i.e. May to April for each of the three years, viz. 2007-08, 2008-09 and 2009-10 to assess comparative performance of SIF and normalized difference vegetation index (NDVI) for predicting net primary productivity (NPP) over the Indo-Gangetic Plains, India. Results show that SIF values for C4 crop-dominated districts were higher than C3 crop-dominated districts during summer and low during winter for all three years. SIF explained more or less above 70% of variance in NPP. The variance explained by integrated NDVI ranged from 60% to 67%. Thus the present study has shown the potential of SIF data for improved modelling of agricultural productivity at a regional scale. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
59. Direct cost comparison of totally endoscopic versus open ear surgery.
- Author
-
Mohammadi, A, Patel, N, and Jufas, N
- Subjects
- *
COST effectiveness , *EAR surgery , *ENDOSCOPY , *MEDICAL care costs , *COST analysis , *RETROSPECTIVE studies - Abstract
Objective:Totally endoscopic ear surgery is a relatively new method for managing chronic ear disease. This study aimed to test the null hypothesis that open and endoscopic approaches have similar direct costs for the management of attic cholesteatoma, from an Australian private hospital setting.Methods:A retrospective direct cost comparison of totally endoscopic ear surgery and traditional canal wall up mastoidectomy for the management of attic cholesteatoma in a private tertiary setting was undertaken. Indirect and future costs were excluded. A direct cost comparison of anaesthetic setup and resources, operative setup and resources, and surgical time was performed between the two techniques.Results:Totally endoscopic ear surgery has a mean direct cost reduction of AUD$2978.89 per operation from the hospital perspective, when compared to canal wall up mastoidectomy.Conclusion:Totally endoscopic ear surgery is more cost-effective, from an Australian private hospital perspective, than canal wall up mastoidectomy for attic cholesteatoma. [ABSTRACT FROM PUBLISHER]
- Published
- 2018
- Full Text
- View/download PDF
60. Evaluation of remote-sensing-based models of gross primary productivity over Indian sal forest using flux tower and MODIS satellite data.
- Author
-
Watham, T., Patel, N. R., Kushwaha, S. P. S., Dadhwal, V. K., and Kumar, A. Senthil
- Subjects
- *
MODIS (Spectroradiometer) , *SATELLITE-based remote sensing , *REMOTE sensing devices , *CLIMATE change , *FORESTS & forestry - Abstract
Forest plays a significant role in regulating the carbon budget and mitigating climate change in long term. However, lack of spatially explicit and accurate information on carbon exchange components from diverse forest ecosystem types in India limits carbon budgeting on a regional scale. Remote-sensing-driven ecosystem models are well-established tools for estimating gross primary productivity (GPP) over large areas but they are seldom found erroneous if implemented without proper calibration of biome-specific parameters. The present study evaluates the combined use of eddy covariance (EC) data and satellite-derived variables for estimating GPP over large areas. Four remote-sensing-driven models, (i) temperature–greenness (TG) model, (ii) greenness–radiation (GR) model, (iii) light use efficiency (LUE) model, and (iv) remote-sensing-based LUE (LUERS) model, were parameterized with EC measurements and compared with 8-day Moderate Resolution Imaging Spectroradiometer (MODIS) GPP products for a moistShorea robustaforest in northern part of India. EC observed 8-day average GPP varied from 5.38 to 12.42 g C m−2day−1. Among the four tested models, TG model had the highest root mean square error (RMSE) of 1.28 g C m−2day−1, while GR and LUERSmodels had moderate RMSE of 0.99 g C m−2day−1and 0.98 g C m−2day−1, respectively. The closest GPP estimate was given by LUE model with RMSE of 0.93 g C m−2day−1.The RMSE for all four models were four times lower than that of MODIS GPP. Lower maximum LUE (and uncertainty in the environmental scalar used in MODIS GPP algorithm could have contributed to higher RMSE. More accurate modelling of GPP can help in better understanding of forest ecological functions with the changing climate. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
61. Confirming the recessive inheritance of SCN1B mutations in developmental epileptic encephalopathy.
- Author
-
Ramadan, W., Patel, N., Anazi, S., Kentab, A.Y., Bashiri, F.A., Hamad, M.H., Jad, L., Salih, M.A., Alsaif, H., Hashem, M., Faqeih, E., Shamseddin, H.E., and Alkuraya, F.S.
- Subjects
- *
GENETIC mutation , *PEOPLE with epilepsy , *HEPATIC encephalopathy , *DOMINANCE (Genetics) , *EXOMES , *PATIENTS - Abstract
Dominant SCN1B mutations are known to cause several epilepsy syndromes in humans. Only 2 epilepsy patients to date have been reported to have recessive mutations in SCN1B as the likely cause of their phenotype. Here, we confirm the recessive inheritance of 2 novel SCN1B mutations in 5 children from 3 families with developmental epileptic encephalopathy. The recessive inheritance and early death in these patients is consistent with the Dravet-like phenotype observed in Scn1b−/− mice. The 'negative' clinical exome in one of these families highlights the need to consider recessive mutations in the interpretation of variants in typically dominant genes. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
62. Imaging appearances at follow-up after image-guided solid-organ abdominal tumour ablation.
- Author
-
Patel, N., King, A.J., and Breen, D.J.
- Subjects
- *
DESMOID tumors , *ABLATION techniques , *CANCER treatment , *METASTASIS , *DISEASE progression , *TUMOR treatment - Abstract
The role of minimally invasive, locoregional therapies in cancer is increasingly driven by the detection of small asymptomatic disease either incidentally or under surveillance for a known primary malignancy. Percutaneous image-guided ablation has become established as a parenchyma-sparing tool in the management of small volume primary and metastatic disease in the liver as well as solitary renal masses. As ablation is non-extirpative, post-ablation imaging is critical for the assessment of treatment completion, recurrence, and complications. Within established regional cancer networks, understanding of normal post-ablation imaging appearances is essential for the early identification of primary treatment failure or local recurrence, which may be amenable to repeat treatment. We provide an imaging primer of two common ablation sites - kidney and liver - focusing on normal appearances and appreciation of local disease progression. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
63. Magnetic domain confinement using nonplanar substrates.
- Author
-
Patel, N. K. and Pepper, M.
- Subjects
- *
FERROMAGNETIC materials , *CHROMOGENIC compounds - Abstract
Provides information on a study that examined the ferromagnetic films deposited on nonplanar substrates. Procedure to control and position domain walls; Samples used in the study; Results and discussion; Conclusions.
- Published
- 2000
- Full Text
- View/download PDF
64. Validation of the Cardiac Allograft Vasculopathy (CAV) Trajectory Score after Heart Transplantation.
- Author
-
Patel, N., Kittleson, M., Chang, D., Patel, J., Azarbal, B., Singer-Englar, T., Geft, D., Czer, L., Esmailian, F., and Kobashigawa, J.
- Subjects
- *
HEART transplantation , *HOMOGRAFTS , *LEFT ventricular dysfunction , *VASCULAR diseases , *HEART diseases - Abstract
We have recently reported on a CAV score after HTx to predict the development of this complication. The discovery phase of this trajectory score was developed by the Paris Transplant Group with validations at Leuven University Hospital (Belgium) and Cedars-Sinai Heart Institute (USA). The CAV trajectory score was validated to predict outcomes (CAV and survival) after HTx. We now present our real-world experience using the CAV trajectory score for our patient population. For our clinical application of the CAV trajectory score, we used a 70% or greater prediction of either Trajectory 1 or Trajectory 2 to merit the avoidance of annual coronary angiograms. At this selected threshold, there would be a 0.07% chance of any patient developing CAV within 10 years. For these patients, we reduced angiograms to 5-year intervals. We prospectively assessed 19 HTx patients transplanted between 2011 and 2017 who were given CAV trajectory scores which resulted in a prediction of 70% or greater for CAV Trajectories 1 and 2. CAV trajectory scores were calculated in 2020 according to each patient's first-year angiogram results. These patients were followed with at least 1 angiogram avoided prior to their 5- or 10-year angiograms. Patients with new onset LV dysfunction, DSA, and ACR after the first year were deleted from this study as they could no longer be in Trajectory 1 or 2. Those patients with predicted CAV Trajectories 1 and 2 at the first-year post-transplant were entered in a cross-sectional pattern, but all had angiograms at 5- or 10-year post-transplant. 100% of patients at their 5- or 10-year angiogram showed no evidence of CAV, consistent with the predictive model. Furthermore, all patients had no cardiac dysfunction, no rejection, and no abnormal hemodynamics at the time of the angiogram. The mean predicted score for trajectory 1 and 2 was 76% ± 11% (range 71-91%). The CAV trajectory score with 70% or greater prediction of CAV Trajectory Score 1 and 2 appears to be valid in avoiding annual angiograms as no significant clinical presentation for concern occurred in these patients. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
65. A1080 - ESWL: Prematurely falling out of favour? A 10 year audit from a high volume stone centre.
- Author
-
Patel, N., Yao, L., Charlotte, B., and Kothari, A.
- Published
- 2023
- Full Text
- View/download PDF
66. 113: THE PARA-OESOPHAGEAL HERNIA SYMPTOM TOOL (POST): A MODIFIED DELPHI CONSENSUS STUDY.
- Author
-
Puri, A, Patel, N, Sounderajah, V, Ferri, L, Griffiths, E, Low, D, Maynard, N, Mueller, C, Pera, M, Henegouwen, M Van Berge, Zaninotto, G, Hanna, G, and Markar, S
- Subjects
- *
HERNIA , *QUALITY of life , *HEARTBURN , *LIKERT scale , *SYMPTOMS , *TEST validity , *CHEST pain - Abstract
Background and aim Patients with a para-oesophageal hernia (POH) report a range of symptoms and quality of life (QOL) issues. Clinicians often utilise existing health-related quality of life tools to identify patients eligible for surgical management and to evaluate the benefit of surgical intervention. However, the most commonly used tools for this purpose are not disease specific. Therefore, crucial POH-specific symptoms which impact QOL may not be captured. To address this, a modified Delphi consensus study was undertaken to establish a HRQOL instrument specific to POH. Methods A two-round modified Delphi consensus study was conducted with a group of international experts. Participants were identified through their authorship in landmark POH studies and the professional networks of the study investigators. Before the Delphi process, a scoping survey was undertaken to generate a list of candidate items. Participants were asked to rate the items' importance in assessing patients with POH using a 5-point Likert scale. The a priori threshold for inclusion was 80% for scores of 4 or 5. If consensus was not achieved, the item was carried through to the next round. Results The candidate list of items consisted of 64 symptoms, refined to 20 for inclusion within the first modified Delphi round. Four symptoms; 'difficulty getting solid foods down', 'chest pain after meals', 'difficulty getting liquids down' and 'shortness of breath only after meals', reached consensus threshold of 80% in the first round and additionally, 'early feeling of fullness after eating', reached consensus in the second. A total of 26 participants took part in the first and 24 in the second round. These five symptoms form the initial version of the Para-Oesophageal Hernia Symptom Tool (POST). Conclusion POST is the first tool that aims to capture POH-specific symptoms that impact HRQOL. Prior to clinical use, this tool will be presented in international patient workshops to assess its construct validity. Thereafter, we aim to assess the content validity of the tool through a longitudinal study in a cohort of patients with undergoing POH repair. This tool aims to serve as a decision-support tool for clinicians when evaluating the risk–benefit of surgical intervention in this cohort of patients. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
67. Is ATG Induction with Delayed Initiation of CNI Protective of Renal Function in Patients with Mild Renal Insufficiency?
- Author
-
Patel, N., Kittleson, M., Patel, J., Singer-Englar, T., Chang, D., Hage, A., Azarbal, B., Czer, L., Esmailian, F., and Kobashigawa, J.A.
- Subjects
- *
KIDNEY failure , *KIDNEY physiology , *GRAFT rejection , *GLOMERULAR filtration rate - Abstract
Rabbit anti-thymocyte globulin (ATG) therapy has been used for induction to allow delay of initiation of calcineurin inhibitor (CNI) immediately post-heart transplant (HTx) in patients with moderate to severe renal insufficiency. In our program, this approach has been routine for patients with serum creatinine >2.0 mg/dL. Although this mode of therapy has been shown to be effective for renal protection, its benefit has not been established for patients with less renal insufficiency, in the 1.5-2.0 mg/dL range. Therefore, we reviewed our patient population to assess whether ATG induction was renal-protective for these patients. Between 2010 and 2020, we assessed 84 patients with baseline creatinine in the 1.5-2.0 mg/dL range who underwent HTx, and divided them into those who underwent ATG with delay of initiation from CNI to those patients who did not. Patients given ATG (x 5 days) had delayed CNI beginning on days 3-5 post-operatively once urine output was established. Endpoints included comparison of glomerular filtration rate (GFR) at baseline, with change at 6- and 12-months for each group. In addition, 1-year freedom from temporary and chronic dialysis (occurring greater than 30 days postop) and freedom from rejection (any treated rejection [ATR], acute cellular rejection [ACR], antibody mediated rejection [AMR]) was assessed. There was no significant difference in the ATG induction compared to control in renal function (creatinine/GFR) at baseline and change in GFR at 6 months and 1 year post-HTx. In addition, there was no difference between groups in 1-year freedom from temporary or chronic dialysis, and freedom from ATR, ACR, or AMR. ATG induction with delay of CNI does not appear beneficial for kidney function in patients with mild renal insufficiency. Larger studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
68. Primary mastoid reconstruction with Sofradex®-soaked autologous bone pâté: is there a sensorineural hearing effect?
- Author
-
Virk, J.S. and Patel, N.
- Subjects
- *
TREATMENT of hearing disorders , *TREATMENT of deafness , *MASTOID process surgery , *MASTOIDECTOMY , *EAR canal , *ANATOMY - Abstract
The article presents research on the sensorineural hearing effect and effectiveness of Sofradex-soaked autologous for bone pâté epitympanic and mastoid reconstruction after cholesteatoma mastoidectomy. Research shows the significant morbidity caused by modified radical mastoidectomy, the recreation of normal ear canal anatomy using epitympanic and mastoid bony obliteration, and the absence of adverse sensorineural hearing effects from Sofradex.
- Published
- 2017
- Full Text
- View/download PDF
69. Co-Mo-B Nanoparticles as a non-precious and efficient Bifunctional Electrocatalyst for Hydrogen and Oxygen Evolution.
- Author
-
Gupta, S., Patel, N., Fernandes, R., Hanchate, S., Miotello, A., and Kothari, D.C.
- Subjects
- *
NANOPARTICLES , *ELECTROCATALYSTS , *OXYGEN evolution reactions , *BIFUNCTIONAL catalysis , *ELECTROLYSIS - Abstract
This work reports, for the first time, Co-Mo-B as a bifunctional electrocatalyst, prepared by a facile reduction method. The optimized catalyst, Co-3Mo-B shows excellent HER performance and achieves 10 mA/cm 2 at mere 96 and 66 mV (vs RHE) in pH 7 and pH 14, respectively with good stability (40 hours) and reusability (5000 cycles). Co-3Mo-B catalyst is found to be made up of nano-sized crystalline domains, separated by grain boundaries containing active under-co-ordinated sites. From morphological, physico-chemical and electrochemical analyses, it was found that Co-3Mo-B nanoparticles (NPs) exhibit small size (∼18 nm) with high specific and electrochemical surface area. Under alkaline conditions, Co-3Mo-B can also produce oxygen at meagre overpotentials (10 mA/cm 2 at 320 mV) with favourable stability. Bifunctional property is demonstrated by employing Co-3Mo-B in a 2-electrode alkaline cell to execute overall water electrolysis, producing 10 mA/cm 2 at just 1.69 V, which is maintained for at least 25 hours of operation. The nature of the catalyst to form Co oxide/hydroxide species on the surface is responsible for good OER performance. The significant activity of Co-3Mo-B makes it the best metal boride bifunctional electrocatalyst reported so far. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
70. DEVELOPMENT AND VALIDATION OF HPLC METHOD FOR QUANTITATIVE ESTIMATION OF NUCIFERINE FROM LOTUS LEAVES.
- Author
-
Patel, N. A. and Jadhav, A. P.
- Subjects
- *
EAST Indian lotus , *NELUMBONACEAE , *MEDICINAL plants , *LEAVES , *TREATMENT of fever , *HYPERLIPIDEMIA treatment , *THERAPEUTICS - Abstract
Nelumbo nucifera Gaertn (Family: Nelumbonaceae), commonly known as lotus, is an aquatic perennial plant. The lotus leaves are used to treat fever, hematemesis, hyperlipidaemia and obesity. The leaves are rich in alkaloids such as nuciferine, roemerine, pronuciferine and N-nornuciferine. The present study describes simple, accurate, precise, robust RP-HPLC method to detect and quantitate nuciferine as a marker from lotus leaves. The marker was resolved using Hemochrom Intsil C-18 column, with mobile phase methanol:10mm phosphate buffer (85:15), pH adjusted to 4 (using orthophosphoric acid) at a flow rate of 1 mL/min. Retention time of nuciferine was 5.60±0.2 minutes at 272 nm. Linear responses were obtained in concentration range of 1 - 9 ppm for nuciferine with correlation coefficient (r2) of 0.9996. The developed method was applied for quantitation of marker from lotus leaves. This method can be used to evaluate nuciferine containing extracts, thus conforming to the need of ensuring quality and safety of herbal drugs. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
71. Co–Ni–B nanocatalyst for efficient hydrogen evolution reaction in wide pH range.
- Author
-
Gupta, S., Patel, N., Fernandes, R., Kadrekar, R., Dashora, Alpa, Yadav, A.K., Bhattacharyya, D., Jha, S.N., Miotello, A., and Kothari, D.C.
- Subjects
- *
ELECTROCATALYSTS , *HYDROGEN evolution reactions , *COBALT alloys , *PH effect , *NANOSTRUCTURED materials synthesis , *CATALYTIC activity - Abstract
Amorphous Co–Ni–B nanocatalyst with high electrocatalytic activity toward hydrogen evolution reaction (HER) in wide pH range was successfully synthesized. The content of Ni was varied by adjusting the molar ratio Ni/(Ni + Co) in Co–Ni–B from 10% to 50% to identify the most suitable composition for HER. Co-30Ni–B (with 30% Ni/(Ni + Co)) showed the highest catalytic activity and could reach a current density of 10 mA/cm 2 at just 170 mV in pH 7 and 133 mV in pH 14. It also exhibited a Tafel slope value of 51 mV/dec in pH 7 suggesting Volmer-Heyrovsky reaction mechanism for HER. The role of each element in improving the activity was justified with results from XPS, XAS and DFT calculations. It was observed that the presence of Ni promotes higher electron density at Co active sites of Co–Ni–B which in turn facilitates efficient reduction reaction to enhance HER rate. Co-30Ni–B could sustain 1000 cycles and prolonged hours of operation for about 40 h without losing activity making it an excellent low-cost electrocatalyst material. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
72. Effect of growth regulators and stages of spray on seed yield and seed quality parameters of ridge gourd [Luffa acutangula (Roxb) L.].
- Author
-
Jyoti, Sondarva, Patel, N. B., and Patel, J. B.
- Subjects
- *
GROWTH regulators , *LUFFA , *SEEDS , *GERMINATION , *FRUIT - Abstract
The experiment was undertaken to study the influence of different growth regulators on seed yield and seed quality parameters in ridge gourd [Luffa acutangula (Roxb) L.]. There were 30 treatment combinations comprising of two factors; plant growth stage as main plot treatment, and plant growth regulators as sub plot treatment embedded in a split plot design. The results indicated that significantly the highest average fruit weight (32.76 g), matured fruit yield per plant (65.84 g), 100 seed weight (13.41 g) and seed yield per plant (12.79 g) was recorded with spraying of 500 ppm ethereal, whereas significantly the maximum fruit length (20.89 cm) and fruit diameter (5.15 cm) with 25 ppm GA3. Significantly the highest seed germination (69.22 %) was recorded with spraying of 250 ppm ethereal, while application of NAA at 50 ppm recorded significantly the highest vigour index I (2737.85) and vigour index II (5029.33). Spraying of PGR at two to four leaf stage recorded the higher fruit length (20.19 cm), fruit yield per plant (47.49 g), 100 seed weight (13.18 g) and seed yield per plant (11.98 g) as well as highest germination (60.90%), vigour index I (2460.80) and vigour index II (4377.66). It is concluded that spraying of 500 ppm etherel at two to four leaf stage increased the higher fruit length, fruit yield per plant, 100 seed weight and seed yield per plant as well as highest germination, vigour index I and vigour index II. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
73. High baseline bilirubin and low albumin predict liver decompensation and serious adverse events in HCV-infected patients treated with sofosbuvir-containing regimens.
- Author
-
Perumalswami, P. V., Patel, N., Bichoupan, K., Ku, L., Yalamanchili, R., Harty, A., Motamed, D., Khaitova, V., Chang, C., Grewal, P., Liu, L., Schiano, T. D., Woodward, M., Dieterich, D. T., and Branch, A. D.
- Subjects
- *
HEPATITIS C treatment , *DISEASE incidence , *HEPATITIS C virus , *ALBUMINS , *BILIRUBIN , *COHORT analysis , *PATIENTS ,SOFOSBUVIR - Abstract
To conduct surveillance and determine the safety profile of new hepatitis C virus treatments in real-world clinical practice. Hepatic decompensation and other serious adverse events were investigated in an observational cohort study of 511 patients treated with regimens containing sofosbuvir, December 2013-June 2014. Among 499 previously stable patients (no history of hepatic decompensation during the previous 12 months), a nested case-control study was performed to identify predictors of decompensation/serious adverse event. Cases and controls were matched 1:5 based on treatment regimen and duration. Matched conditional logistic regression was used for analysis. Providers scored the likelihood that events were treatment-related (scale = 0-4). The cumulative incidence of decompensation/events was 6.4% for the total cohort. Among 499 previously stable patients, the incidence of decompensation/events was 4.5%; the mortality rate was 0.6%. Sixteen of the 499 experienced one or more serious complications considered to be at least potentially treatment-related, and the sustained virological response rate was 7/16 (44%). Two cases, both on sofosbuvir/simeprevir (without interferon or ribavirin), had complications consistent with autoimmune events (score 3, 'likely treatment-related'), and one experienced a flare of autoimmune hepatitis. Compared to controls, cases had higher baseline median model for end-stage liver disease scores (14 vs 8, P < 0.01). Decompensation/events was independently associated with lower baseline albumin ( OR = 0.12/g/dL, P = 0.01) and higher total bilirubin ( OR = 4.31/mg/dL, P = 0.01). Reduced hepatic function at baseline increased the risk of liver decompensation/events. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
74. EE373 Assessment of Extent and Quality of Pharmacoeconomic Studies in India Using Quality of Health Economic Studies (QHES) Score: A Targeted Literature Review.
- Author
-
Patel, N, Yanamala, S, Gautam, R, and Rai, MK
- Subjects
- *
LITERATURE reviews - Published
- 2022
- Full Text
- View/download PDF
75. 89 (PB-089) Poster - Accuracy of pre-operative axillary US and biopsy in breast cancer patients.
- Author
-
Hudson-Phillips, S., Patel, N., Akthar, H., Morris, A., and Noor, L.
- Subjects
- *
BIOPSY , *PREDICTIVE tests , *PREOPERATIVE period , *AXILLA , *CONFERENCES & conventions , *CANCER patients , *BREAST tumors - Published
- 2022
- Full Text
- View/download PDF
76. INTEGRATED NUTRIENT MANAGEMENT (INM) APPROACH FOR BRINJAL (SOLANUM MELONGENA L.) AND OTHER SOLANACEOUS VEGETABLES -A REVIEW.
- Author
-
Saravaiya, S. N., Patel, N. B., Ahir, M. P., Patel, N. M., Desai, K. D., and Patel, J. B.
- Subjects
- *
EGGPLANT growing , *FRUIT quality , *SOIL fertility , *CROP nutrition , *CROP yields , *AGRICULTURAL productivity , *ORGANIC farming , *MICRONUTRIENTS - Abstract
Integrated Nutrient Management (INM) implies the most efficient use and management of organic, inorganic and biological sources of major nutrients as well as micronutrients to attain higher levels of crop productivity and to maintain the fertility of the soil. Brinjal is one of the most popular and commercially important vegetable crops of India. Research works on INM system for brinjal crop is scanty. This paper has reviewed the research work carried out by various scientists in India and abroad. The review deals with the effect of different INM components on growth, yield, fruit quality, nutrient content and uptake, incidence of brinjal shoot and fruit borer (BSFB) as well as economics of brinjal and other Solanaceous vegetables. [ABSTRACT FROM AUTHOR]
- Published
- 2010
77. Effect of induced mutagenesis in M1 and M2 generations of cumin (Cuminum cyminum L.).
- Author
-
Patel, H. N., Patel, M. P., Soni, N. V., Patel, N. B., Patel, A. M., and Patel, N. I.
- Abstract
Cumin is an important spice that has been used for centuries in various cuisines around the world. Two cumin varieties (GC 3 and GC 4) were subjected to mutation to understand macromutational modifications. Ethyl methane sulphonate (EMS) @ 0.6% and gamma rays (190 Gy) significantly reduced germination and plant survival percentage as compared to 0.2% EMS and 130 Gy. Physical mutagens showed higher plant suravival than chemical mutagens. However, chemical mutagen treated plants showed more sterility than physical mutagens. Chlorophyll mutations were confined to rare albinos and small number of xanthas in the M2 generation. Morphological changes viz., miniature, loosly branched and thick stem were effective with seed treatment of 0.4% EMS for GC 3 and with 0.6% EMS for GC 4. The estimates of mutagenic efficiency varied with 0.6% EMS and 160 Gy for GC 3, while it varied with 0.6% EMS and 190 Gy for GC 4. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
78. Transtympanic balloon dilatation of the eustachian tube: systematic review.
- Author
-
Jufas, N and Patel, N
- Subjects
- *
EUSTACHIAN tube surgery , *CATHETERIZATION , *INFORMATION storage & retrieval systems , *MEDICAL databases , *MEDICAL information storage & retrieval systems , *MEDLINE , *PATIENT safety , *SYSTEMATIC reviews , *TREATMENT effectiveness - Abstract
Objective:To investigate the evidence for balloon dilatation of the eustachian tube using a transtympanic approach.Methods:A systematic search of several databases was conducted (using the search terms ‘dilation’ or ‘dilatation’, and ‘balloon’ and ‘eustachian tube’). Only studies that used a transtympanic approach for the procedure were included. These studies were then assessed for risk of bias.Results:Three studies were included. Each of these studies was a limited case series, with two performed on human subjects and one on human cadavers. Results of safety and efficacy are conflicting. There is a high risk of bias overall.Conclusion:At present, there is a very narrow evidence base for transtympanic balloon dilatation of the eustachian tube. There are a number of advantages and disadvantages of the technique. Previously identified and theoretical safety concerns will need to be addressed thoroughly in future studies prior to wider clinical use. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
79. Efficient Co-B-codoped TiO2 photocatalyst for degradation of organic water pollutant under visible light.
- Author
-
Jaiswal, R., Patel, N., Dashora, Alpa, Fernandes, R., Yadav, M., Edla, R., Varma, R.S., Kothari, D.C., Ahuja, B.L., and Miotello, A.
- Subjects
- *
TITANIUM dioxide , *PHOTOCATALYSTS , *DOPING agents (Chemistry) , *BIODEGRADATION of organic water pollutants , *VISIBLE spectra , *CATALYTIC activity , *SOL-gel processes - Abstract
Lattice location of B in TiO 2 is tuned to determine its effect on the photocatalytic activity of Co-B codoped TiO 2 . Sol–gel method was used to synthesize the samples. The concentrations of Co and B were first optimized by maximizing the photocatalytic activity for the monodoped (Co or B)-TiO 2 . In addition to the DFT calculations for discovering new energetic levels introduced in TiO 2 by codoping, various characterization techniques were used to determine the dopant lattice sites in TiO 2 and interactions between them; and also determining their consequences on electronic, morphological, structural, and optical properties. At low concentration of B-doping (1 at.%), B occupies the interstitial site (B int ), but as the concentration increases (2 at.% and 3 at.%) B also occupies substitutional O position (B sub ) in addition to B int to form TiO 2 containing B int+sub . Both these B-doped TiO 2 showed improved photocatalytic activity attributed to effective charge separation obtained for TiO 2 –B int due to the formation of shallow energy level while higher visible light absorption is achieved with TiO 2 –B int+sub owing to the presence of two deep energy levels in the band gap as confirmed by DFT calculations. In the case of Co doping, the band gap of TiO 2 is reduced but the recombination rates are always high and are caused by the formation of Co states in the band gap. For Co monodoped TiO 2 , the photocatalytic activity is low for all the concentrations considered, except for very low concentration of Co (0.1 at.%). Two opposite effects were observed when small amount of Co (0.1 at.%) was codoped with B int or B int+sub . In particular, the photocatalytic degradation rate of organic aqueous pollutants ( p -nitrophenol and rhodamine B dye) reduces for TiO 2 –Co–B int whereas it is enhanced remarkably for TiO 2 –Co–B int+sub as compared to (Co or B) monodoped (∼2.1 times) and undoped (∼7.8 times) TiO 2 . Higher photocatalytic activity observed in Co-doped TiO 2 –B int+sub is discussed in terms of the interactions of Co with B at two different lattice positions in TiO 2 and the synergistic effect created by higher visible light absorption and the improved charge separation. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
80. The relationship among gastroparetic symptoms, quality of life, and gastric emptying in patients referred for gastric emptying testing.
- Author
-
DiBaise, J. K., Patel, N., Noelting, J., Dueck, A. C., Roarke, M., and Crowell, M. D.
- Subjects
- *
GASTRIC emptying , *GASTROPARESIS , *LOGISTIC regression analysis , *QUALITY of life , *DIGESTION , *INTESTINAL absorption , *ABDOMINAL bloating - Abstract
Background Symptoms suggestive of gastroparesis are non-specific and conflicting reports exist regarding the ability of symptoms to predict the presence of gastroparesis. Our aim, therefore, was to evaluate the relationships between gastroparetic symptoms and their impact on quality of life and determine their relationship with clinical factors and gastric emptying. Methods Gastric emptying scintigraphy, sociodemographic features, health care resource utilization, gastroparetic symptoms, and quality of life using validated questionnaires were obtained from consecutive patients referred for gastric emptying testing ( GET). Descriptive analyses were conducted and logistic regression was performed to evaluate associations with abnormal gastric emptying after controlling for other covariates. Key Results Two hundred and sixty-six patients participated (195 females; mean age, 49.1 ± 17.6 years); 75% met Rome III criteria for functional dyspepsia. Gastric emptying was delayed in 28.2% at 4 h; the delay was mild in 48%, moderate in 20% and severe in 32%. Nausea/emesis and postprandial fullness, but not bloating, were significantly greater in those with delayed emptying. Postprandial fullness was most severe. Weak correlations were identified between symptom severity and the severity of gastric emptying delay. Quality of life was also lower in the delayed emptying group. Logistic regression analysis demonstrated associations between delayed gastric emptying and lower quality of life and increased symptom severity. Conclusions & Inferences In patients referred for GET, gastroparetic symptoms were more severe in those with delayed emptying. A decrease in quality of life in those with delayed gastric emptying was also present; this was not related to the severity of the delay in gastric emptying. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
81. Memory deficits associated with khat ( Catha edulis) use in rodents.
- Author
-
Kimani, S., Patel, N., and Kioy, P.
- Subjects
- *
MEMORY disorders , *COGNITION disorders , *KHAT , *CATHA , *PSYCHOTROPIC plants - Abstract
Khat products and chewing practices are common in East Africa, Middle East for centuries with concomitant socio-economic and public health repercussions. We assessed memory deficits associated with khat use in rodents. Young male CBA mice, 5-7 weeks old ( n = 20), weighing 25-35 g were used. Mice were treated with either 40, 120 or 360 mg/kg body weight (bw) methanolic khat extract, or 0.5 ml saline for 10 days. Spatial acquisition, reversal and reference memory were assessed using modified Morris Water maze (MMWM). Mice treated with 40 mg/kg khat extract had longer (t = 4.12 p = 0.015) and t = 2.28 p = 0.065) escape latency on first and second day during reversal relative to the baseline. Under 120 mg/kg khat dose, the escape latency was shorter (t = −2.49 p = 0.05) vs (t = −2.5 p = 0.05) on third and fourth day. Further, treatment with 360 mg/kg khat extract resulted in significantly longer time (49.13, 33.5, 40.2 and 35.75) vs. (23.5 s), compared to baseline. Mice treated with khat or control preferred the target quadrant post acquisition while differential pattern was seen during reversal phase. Mice treated with 40 or 120 mg/kg khat showed significant preference for target quadrant. Substantial time (19.9) was spent in the old target compared to the new (16.9 s) by animals treated with highest dose however, the difference was not significant. There is a biological plausibility that chronic khat use may induce memory deficits and impair cognitive flexibility. The differential patterns of memory deficits may reflect the differences in dose effect as well as time dependent impairment. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
82. Heterosis for yield and its related traits in Okra (Abelmoschus esculentus L. Moench).
- Author
-
Bhatt, J. P., Patel, N. A., Acharya, R. R., and Kathiria, K. B.
- Subjects
- *
HETEROSIS in plants , *OKRA , *PLANT yields , *FLOWER varieties , *PLANT breeding - Abstract
Eight parental lines of okra and their 28 F1 hybrids obtained from half diallel were studied to investigate the extent of heterosis for yield and yield attributing characters. The magnitude of heterosis varied from cross to cross for all the characters studied. Maximum positive heterosis for fruit yild per plant over better parent and standard check (JOH 2) was observed to be 62.12 and 44.11 per cent, respectively. The cause of heterosis may be due to its component traits, mainly, days to first flowering, nodes per plant, length of internode, fruit weight and fruits per plant. The best performing hybrid AOL 09-25 x AOL 09-26 which recorded 44.11 per cent heterosis for yield over standard check may be exploited for commercial cultivation. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
83. Assessment of atopic dermatitis using self-report and caregiver report: a multicentre validation study.
- Author
-
Silverberg, J.I., Patel, N., ImmanENi, S., Rusniak, B., Silverberg, N.B., Debashis, R., Fewkes, N., and Simpson, E.L.
- Subjects
- *
ECZEMA , *REPORTING of diseases , *CAREGIVERS , *SENSITIVITY & specificity (Statistics) , *CONFIDENCE intervals , *DIAGNOSIS - Abstract
Background The epidemiology of atopic dermatitis ( AD) in the U.S.A. has been described largely via US population-based questionnaire studies. However, the validity of the questions used for self- and caregiver-reported eczema has not been previously demonstrated. Objectives To validate the assessment of self- and caregiver-reported eczema. Methods We performed a prospective multicentre dermatology-practice-based study (three sites) to determine the validity of caregiver- and self-reported ever having eczema and 1-year history of eczema. Questionnaires were administered to unselected patients prior to their encounter. Patients ( n = 782) were then evaluated by expert dermatologists trained in utilizing the Hanifin and Rajka criteria for AD. Sensitivity, specificity, positive predictive value ( PPV) and negative predictive value were determined. Results Caregiver-reported 1-year history of childhood eczema was found to have a sensitivity (95% confidence interval) of 0·70 (0·59-0·80), specificity of 0·96 (0·93-0·99) and PPV of 0·87 (0·78-0·96) when compared with a physician's diagnosis of AD at that visit. Similarly, self-reported 1-year history of adult eczema was found to have a sensitivity of 0·70 (0·59-0·80), specificity of 0·95 (0·93-0·97) and PPV of 0·76 (0·64-0·85). The specificities and PPVs of a history of ever having caregiver- (0·89, 0·82-0·96 and 0·81, 0·70-0·93) and self-reported eczema (0·97, 0·95-0·99 and 0·91, 0·85-0·97) were high, with a high sensitivity in children (0·83, 0·72-0·95) but not in adults (0·43, 0·37-0·51). Conclusions Self- and caregiver-reported diagnosis of eczema ever or in the past year based on a single question demonstrates sufficient validity for the epidemiological study of AD. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
84. The cost of adverse events from knee surgery in the United Kingdom: an in-depth review of the National Health Service Litigation Authority database.
- Author
-
Chen, A, Patel, N K, Khan, Y, Cobb, J P, and Gupte, C M
- Abstract
Background: There has been a significant rise in the number and value of claims against the National Health Service (NHS), with limited studies on litigation in orthopaedic surgery and none in knee surgery alone. We aimed to examine claims against the NHS involving all aspects of knee surgery with respect to costs and trends.Clinical Relevance: To raise awareness of the reasons for litigation in knee surgery, thus potentially improve patient care and reduce future claims.Methods: We analysed the NHS litigation authority (NHSLA) database for all orthopaedic surgery claims reported to the NHSLA between 2005 and 2010, with calculation of litigation success rates and odds ratios for those relating to knee surgery.Results: There were 515 cases identified from the 4609 orthopaedic cases in the NHSLA database (11.2%): 298 (58%) involving total knee replacements (TKRs), 11 (2%) involving unicondylar knee replacements, and 90 cases (30%) remaining open. The total pay out for closed cases was £10.45 million and amputation following TKR resulted in the highest single pay out. Litigation success rates for claimants were highest for retained drains (100%), incorrect prosthesis/prosthesis size (78%), renal failure (75%), poor outcome requiring further surgery (74%) and malalignment (71%). There were also 60 cases of delayed diagnosis which resulted in pay outs totalling £2.90 million. Based on these data, projected future pay out costs for the open TKR cases were estimated to be £2.71 million.Conclusion: Litigation success rates for TKR were highest following technical errors such as malalignment compared to events less under the surgeon's control, such as infection. The number of claims involving incorrect prosthesis/size continues to be of concern. Despite the increased availability of imaging modalities, missed diagnosis also resulted in substantial pay outs. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
85. Dermatology virtual consultations: are we providing the best care for our patients?
- Author
-
Patel, N. P. and Fearfield, L.
- Subjects
- *
SKIN cancer , *DERMATOLOGY , *DERMATOLOGISTS , *MEDICAL students , *MEDICAL personnel , *COVID-19 pandemic , *COVID-19 - Abstract
As many countries start to recover from a second wave of COVID-19 infection, the dermatology community must now seriously consider how it wishes dermatology services to be provided in future. We support the employment of innovative technology to enhance the patient experience, but consider that dermatology patient care is overall best administered FTF, and hope that the dermatology community supports efforts to reinstitute FTF consultations when safe to do so. [Extracted from the article]
- Published
- 2021
- Full Text
- View/download PDF
86. MRI directed bilateral stimulation of the subthalamic nucleus in patients with Parkinson's disease.
- Author
-
Patel N K, Plaha P, O'Sullivan K, McCarter R, Heywood P, Gill S S, Patel, N K, Plaha, P, O'Sullivan, K, McCarter, R, Heywood, P, and Gill, S S
- Subjects
- *
BRAIN function localization , *BRAIN stimulation , *NEUROPHYSIOLOGY , *MAGNETIC resonance imaging - Abstract
Objective: Bilateral chronic high frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has emerged as an appropriate therapy for patients with advanced Parkinson's disease refractory to medical therapy. Advances in neuroimaging and neurophysiology have led to the development of varied targeting methods for the delivery of this treatment. Intraoperative neurophysiological and clinical monitoring is regarded by many to be mandatory for accurate STN localisation. We have examined efficacy of bilateral STN stimulation using a predominantly magnetic resonance imaging (MRI)-directed technique.Methods: DBS leads were stereotactically implanted into the STN using an MRI directed method, with intraoperative macrostimulation used purely for adjustment. The effects of DBS were evaluated in 16 patients followed up to 12 months, and compared with baseline assessments. Assessments were performed in both off and on medication states, and were based on the Unified Parkinson's Disease Rating Scale (UPDRS) and timed motor tests. Functional status outcomes were examined using the PDQ-39 quality of life questionnaire. A battery of psychometric tests was used to assess cognition.Results: After 12 months, stimulation in the off medication state resulted in significant improvements in Activities of Daily Living and Motor scores (UPDRS parts II and III) by 62% and 61% respectively. Timed motor tests were significantly improved in the off medication state. Motor scores (UPDRS part III) were significantly improved by 40% in the on medication state. Dyskinesias and off duration were significantly reduced and the mean dose of L-dopa equivalents was reduced by half. Psychometric test scores were mostly unchanged or improved. Adverse events were few.Conclusions: An MRI directed targeting method for implantation of DBS leads into the STN can be used safely and effectively, and results are comparable with studies using intraoperative microelectrode neurophysiological targeting. In addition, our method was associated with an efficient use of operating time, and without the necessary costs of microelectrode recording. [ABSTRACT FROM AUTHOR]- Published
- 2003
- Full Text
- View/download PDF
87. Paediatric splenectomy: The Johannesburg experience.
- Author
-
Patel, N., Nicola, A., Bennet, P., Loveland, J., Mapunda, E., and Grieve, A.
- Subjects
- *
SPLENECTOMY in children , *TREATMENT effectiveness , *BLOOD disease treatment , *LENGTH of stay in hospitals , *PUBLIC health - Abstract
Background. Splenectomy is an uncommon procedure in children, and data on children who underwent splenectomy in South Africa are sparse. Objective. To describe the profile, operative management and outcomes of children undergoing splenectomy. Methods. The records for all children aged 0 to 16 years who underwent splenectomy at Charlotte Maxeke Johannesburg Academic (CMJAH) and Chris Hani Baragwanath Academic (CHBAH) hospitals between 2000 and 2015 were reviewed. Student's t-tests and ϰ² tests were used to analyse the data. Results. The mean age at surgery was 9.9 years (range 3-16). Most splenectomies (91%; n=30/33) were performed for haematological disorders and were open (67%; n=22/33). The mean post-operative length of stay (LOS) was shorter in the laparoscopic (4.5 days) than the open (7.1 days) groups (p<0.05). Surgical complications were more common in the laparoscopic (36%, 4/11) than open (9%; n=2/22) group, and in children older than the mean age at time of surgery. No cases of overwhelming post splenectomy infection (OPSI) were noted. At study completion, 61% (n=20/33) of patients were alive, 9% (n=3/33) had demised, and 30% (n=10/33) were lost to follow-up. Conclusion. Local indications for paediatric splenectomy mirror those found in international literature. Mean and median postoperative lengths of stay (LOS) were shorter in the laparoscopic than open group, but relatively longer for both groups than reported internationally. Laparoscopy is not currently the preferred technique for splenectomy in our setting. All mortalities were due to progression of underlying disease and no cases of OPSI were recorded. The high loss-to-follow-up rate in this study is a significant barrier to accurate data collection, analysis and reporting. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
88. A novel mutation in SLC25A46 causes optic atrophy and progressive limb spasticity, with no cerebellar atrophy or axonal neuropathy.
- Author
-
Sulaiman, R.A., Patel, N., Alsharif, H., Arold, S.T., and Alkuraya, F.S.
- Subjects
- *
GENETIC mutation , *PERIPHERAL neuropathy , *MITOCHONDRIAL DNA - Published
- 2017
- Full Text
- View/download PDF
89. Interactions of basic compounds with ionic liquids used as oils in microemulsion liquid chromatography.
- Author
-
Pankajkumar-Patel, N., Peris-García, E., Ruiz-Angel, M.J., and García-Alvarez-Coque, M.C.
- Subjects
- *
MICELLAR liquid chromatography , *MICROEMULSIONS , *LIQUID chromatography , *IONIC liquids , *ANIONIC surfactants , *SODIUM sulfate , *PHENOLIC acids - Abstract
• Use of methylimidazolium ionic liquids in microemulsion liquid chromatography. • Analysis of β-adrenoceptor antagonists using ionic liquids of diverse polarity. • Effect on retention of the alkyl chain lengths and anions in the ionic liquids. • Effect of the ionic liquid nature on the peak profiles. • Behaviour of ionic liquid/surfactant mixtures without organic solvent. Aqueous microemulsions (MEs), where an oil coexists with water in the presence of the anionic surfactant sodium dodecyl sulphate (SDS), have been proposed as a solution to decrease the amount of organic solvent in the mobile phase needed in reversed-phase liquid chromatography (RPLC). However, the oil phase of a typical ME is volatile, toxic and flammable, and although it is added in a small amount, it would be desirable to avoid it from an environmental perspective. This is the reason for the proposal of Peng et al. (J. Chromatogr. A 1499 (2017) 132‒139) to replace the oil in microemulsion liquid chromatography (MELC) by the apolar ionic liquid (IL) 1-hexyl-3-methylimidazolium hexafluorophosphate ([C 6 C 1 IM][PF 6 ]), to analyse neutral phenolic acids at acidic pH. Based on this report, an MELC procedure is here proposed for β-adrenoceptor antagonists, which are basic compounds where the dominant species is cationic. To verify the formation of MEs containing SDS and IL, and elucidate the interactions between the cationic basic compounds with the SDS anion, and the cation and anion in the IL, an extensive study was carried out with several methylimidazolium ILs containing the cations [C 2 C 1 IM]+, [C 4 C 1 IM]+, or [C 6 C 1 IM]+, combined with the anions Cl–, BF 4 –, or PF 6 –, using 1-butanol as co-surfactant. The behaviour was compared with that observed in classical MELC with octane, micellar liquid chromatography with SDS and 1-propanol, and RPLC with mobile phases containing an IL and acetonitrile. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
90. Expression of MMP2, MMP9 and PGP 9.5 in human aorta in patients with coronary artery disease.
- Author
-
Patel, N and Chandrashekhar, R
- Subjects
- *
CORONARY artery disease , *MATRIX metalloproteinases , *AORTA , *AORTIC valve diseases , *CAROTID intima-media thickness , *COMPLEX regional pain syndromes ,AORTIC valve surgery - Abstract
Funding Acknowledgements Type of funding sources: None. Atherosclerosis has been recognised as inflammatory conditions which involves activation of MMPs of which increased MMP2 & MMP9 expression has been correlated with the development of human aortic plaques.The Sympathetic Nervous System exerts complex control over inflammation in atherosclerosis both: on systemic scale and at the regional level.Protein gene product9.5 (PGP9.5) is a cytoplasmic neuron & is a reliable marker for visualisation of the cardiovascular system innervation.There have been no studies in the existing literature on the expression of PGP 9.5 and MMP2, MMP9 on human aorta.Aim:To study the expression of MMP2, MMP9 and PGP9.5 in the human aorta & gain insights into atherosclerosis & neural modulation in the aorta.Materials & Methods This is a single centre, prospective cohort, pilot study with a sample size of 87 patients,done over 2 years at AIMS,Kochi.During CABG, punch biopsy of the aorta taken & processed.One paraffin embedded section used for routine H&E staining & others used for IHC.IHC detection kits use 3, 3'-DABChromogen as a substrate of HRP for visualisation of antigenic structures in the tissues.Positive & negative control tissue were run for all 3 Antibodies.Interpretation done as Diffuse/Focal & Intense/Moderate/ Weak classification based on intensity signals observed on IHC by an experienced Cardiac Pathologist.Results:7 Controls with well matched baseline characteristics: Controls-Aorta samples taken from patients who were undergoing Aortic Valve Surgery for Aortic Valve disease with normal coronaries documented on a coronary angiogram.65.9% of patients with Positive MMP2 & 28.6 % of patients in the Control group was found to have significant difference when compared to positive & negative outcomes amongst the 2 groups.89.3% of patients with positive MMP2 had significant co-relation with PGP9.5 levels expressed in the same specimen analysed.MMP9 also had a p value of 0.002 suggesting a significant co-relation between MMP9 & PGP9.5.Statistically significant Co-relation seen between the Age, CRP & the levels of MMP 9 expressed in the Aorta observed.MMP2 & MMP9 expression have a definite & significant co-expression with PGP9.5 expression in human aorta,suggesting a novel marker of neuromodulation in atherosclerotic process in human aorta. Expression of MMP2, MMP9 and PGP 9.5 in human aorta in patients with coronary artery disease Open in new tab Download slide Cases vs Control [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
91. 1069 ESSENTIAL FRAILTY TOOLSET AS A PREDICTOR OF PROLONGED LENGTH OF STAY AND DISCHARGE DESTINATION AFTER TRANSCATHETER AORTIC VALVE IMPLANTATION.
- Author
-
Patel, N, Teh, W, Omoniyi, O, Martin, W, Weir-McCall, J, D'Errico, L, O'Sullivan, M, Davies, W, Costopoulos, C, and Costanzo, P
- Subjects
- *
LENGTH of stay in hospitals , *FRAIL elderly , *HEART valve prosthesis implantation , *RISK assessment , *POSTOPERATIVE period , *TELECONFERENCING , *DISCHARGE planning - Abstract
Introduction Frailty is associated with poor outcomes following transcatheter aortic valve implantation (TAVI). Rockwood is the widely used score for this population. In a recent trial, a more objective score, the Essential Frailty Toolset (EFT) outperformed Rockwood's in predicting mortality and disability 1-year post-TAVI. Whether it predicts in-hospital length of stay (LOS) and discharge destination post-TAVI remains unclear. Method A cohort of patients undergoing TAVI for aortic stenosis was recruited, demographic characteristics collected, and frailty assessed with EFT and Rockwood scores. Primary outcomes were LOS post-TAVI, categorised as 'not prolonged' (≤2 days) or 'prolonged' (>2 days) and discharge destination, characterised as 'home' or 'non-home'. Results 86 patients were recruited, with median age 82 years (IQR 78–86). 54% were male. EFT identified 35% and Rockwood 11% as frail. 19% were cognitively impaired. 5 chair rises were completed by 70%, with 30% managing under 15 seconds. Median haemoglobin was 121 g/L (IQR 109.5–136). Median albumin was 36 g/L (IQR 33–39). 84% of procedures were transfemoral. 20% had moderate–severe left ventricular systolic dysfunction. Median LOS post-TAVI was 2 days (IQR 2–5). 94% were discharged home, 6% to referring local hospital or rehabilitation centre. 46% were NYHA class III-IV. A model for prolonged LOS including comorbidities, showed frailty determined by EFT (OR 4.80, CI 95% 1.52–15.2, p = 0.008) but not Rockwood (OR 5.00, CI 95% 0.865–29.0, p = 0.072) was the only significant independent predictor for prolonged LOS. A model adjusting for comorbidities also showed EFT to be an independent predictor for non-home discharge destination of borderline significance (OR 2.57 CI 95% 0.994–6.66, p = 0.051) but Rockwood was not (OR 1.38 CI95% 0.485–3.91, p = 0.548). Conclusion In a real-world elderly population, EFT score was a stronger, more independent predictor of prolonged LOS and non-home discharge post-TAVI, than Rockwood's. EFT would be an effective pre-operative assessment tool for LOS and discharge destination for TAVI. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
92. EVALI-RELATED PULMONARY TOXICITY.
- Author
-
PATEL, N., MCCANN, T., NAMDARIZANDI, V., and HAYNER, C.
- Published
- 2022
- Full Text
- View/download PDF
93. P161 Body mass index change in adult patients with cystic fibrosis following the introduction of triple CFTR therapy elexacaftor/tezacaftor/ivacaftor: a regional adult cystic fibrosis centre experience.
- Author
-
Barrett, J., Patel, N., Rashid, R., and Whitehouse, J.L.
- Published
- 2022
- Full Text
- View/download PDF
94. Successful Haploidentical Donor Hematopoietic Stem Cell Transplant and Restoration of STAT3 Function in an Adolescent with Autosomal Dominant Hyper-IgE Syndrome.
- Author
-
Patel, N., Gallagher, J., Torgerson, T., and Gilman, A.
- Subjects
- *
HEMATOPOIETIC stem cell transplantation , *IMMUNODEFICIENCY , *ADOLESCENT health , *GENETIC mutation , *STAT proteins , *HEALTH outcome assessment , *PATIENTS - Abstract
Purpose: Autosomal dominant hyper-IgE syndrome (AD-HIES), caused by mutations in Signal Transducer and Activator of Transcription 3 (STAT3) is associated with defective STAT3 signaling and Th17 differentiation and recurrent bacterial and fungal infections. Most patients suffer significant morbidity and premature mortality. Hematopoietic stem cell transplantation (HSCT) has been reported in a small number of cases, with mixed outcomes. We report successful haploidentical donor HSCT in a patient with AD-HIES. Methods: Evaluation of lymphocyte subsets, STAT3 signaling, and Th17 cells was performed pre- and post-HSCT. Results: A 14-year old female with AD-HIES developed recurrent methicillin-resistant Staphylococcus aureus (MRSA) abscesses. Immunologic analysis showed elevated IgE (4331 kU/L), absent Th17 cells, and markedly decreased STAT3 phosphorylation in cytokine stimulated peripheral blood mononuclear cells. She had breakthrough abscesses despite clindamycin and trimethoprim-sulfamethoxazole prophylaxis, and developed steroid refractory autoimmune hemolytic anemia. She underwent T-cell depleted haploidentical HSCT from her father following reduced intensity conditioning. She developed one MRSA hand abscess after transplant. Twenty-four months post transplant, she had complete donor chimerism (>95 % donor), normal absolute T cell numbers, and a normal percentage of Th17 cells. IgE was normal at 25 kU/L. She remains well 42 months after transplantation off all antibacterial prophylaxis. Conclusions: Haploidentical HSCT led to successful bone marrow engraftment, normalization of STAT3 signaling in hematopoietic cells, normalization of IgE, and restoration of immune function in this patient with AD-HIES. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
95. Concerns and perceptions about necessity in relation to insulin therapy in an ethnically diverse UK population with Type 2 diabetes: a qualitative study focusing mainly on people of South Asian origin.
- Author
-
Patel, N., Stone, M. A., McDonough, C., Davies, M. J., Khunti, K., and Eborall, H.
- Subjects
- *
PEOPLE with diabetes , *INSULIN therapy , *TYPE 2 diabetes & psychology , *ASIANS , *EDUCATION , *ETHNIC groups , *INSULIN , *INTERVIEWING , *RESEARCH methodology , *TYPE 2 diabetes , *PATIENT compliance , *SENSORY perception , *POPULATION , *QUALITATIVE research , *LITERATURE reviews , *HUMAN research subjects , *PATIENT selection , *HEALTH literacy - Abstract
Aim To explore attitudes towards insulin acceptance an ethnically diverse population of people with Type 2 diabetes. Methods We conducted semi-structured interviews using a topic guide based on a literature review and findings from our previous study, which explored the perspectives of healthcare professionals about insulin initiation and management. Analysis of data involved undertaking an abductive reasoning approach in response to emerging themes. Results Participants discussed not only their concerns about insulin therapy, but also their views and beliefs about the necessity of insulin. Their attitudes to insulin treatment could be mapped into four main typologies. These fitted with an attitudinal scale based on the Necessity-Concerns Framework described in the medication adherence literature, comprising four attitudes: accepting, sceptical, ambivalent and indifferent. Decisions about accepting insulin involved balancing concerns (such as needle size) against the perceived necessity of insulin (generally, inadequacy of oral medication). The South Asian and white participants had similar concerns, but these were sometimes greater in South Asian participants, because of the influence of negative views and experiences of other insulin users. Conclusions When discussing insulin with people with Type 2 diabetes, healthcare providers need to ensure that they explore and contribute to patients' understanding and interpretation of the necessity of insulin as well as discussing their concerns. Furthermore, they should be aware of how an individual's social context can influence his/her perceptions about the necessity of insulin as well as their concerns, and that this influence may be greater in some South Asian populations. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
96. Highly photo-catalytically active hierarchical 3D porous/urchin nanostructured Co3O4 coating synthesized by Pulsed Laser Deposition.
- Author
-
Edla, R., Patel, N., Orlandi, M., Bazzanella, N., Bello, V., Maurizio, C., Mattei, G., Mazzoldi, P., and Miotello, A.
- Subjects
- *
PHOTOCATALYSIS , *NANOSTRUCTURED materials , *COBALT oxides , *COATING processes , *INORGANIC synthesis , *PULSED laser deposition - Abstract
A porous coating assembled with hierarchical 3D Co 3 O 4 urchin-like particles was synthesized by Pulsed Laser Deposition (PLD) and thermal oxidation. Laser ablation of Co B powder, used as the target material, in oxygen atmosphere formed core–shell particles on the coating surface with mainly a metallic Co core and a mixture of Co, B and O accommodating the shell. The thermal oxidation of these core–shell particles in air at 600 °C induces the morphological transformation to urchin-like particles consisting of nanowires (NWs) (diameter: 30–60 nm and length 1–3 μm) grown radially from the core surface. The extrusion marks on the surface of NWs indicate that the stress induced growth process is caused by difference in the thermal expansion coefficient. XRD, Raman, EXAFS and HRTEM analysis confirmed that the NWs are polycrystalline consisting of pure Co 3 O 4 phase. A wet-chemistry hydrothermal procedure was also employed to synthesize nanostructured urchin-like particles which are hollow and the structure is held together by the radially oriented nanorods (diameter: 40–150 nm). During photocatalysis, urchin-like particles synthesized by PLD displayed significantly higher (∼5 times) degradation rates when compared to chemical urchins for degradation of methylene blue dye via a photo-Fenton reaction in presence of H 2 O 2 and visible light. This is mainly attributed to poor stability of the nanorods in the chemical urchin structure. Features such as high surface area, enhanced stability against agglomeration, polycrystalline nature of the NWs, porous surface and superior adhesion, are responsible for the enhanced photocatalytic activity of Co 3 O 4 urchin-like particles assembled in a porous coating synthesized by PLD and thermal oxidation. Reusability tests also demonstrate the robust nature of the catalyst coating. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
97. Heterozygote to homozygote related living donor liver transplantation in maple syrup urine disease: A case report.
- Author
-
Patel, N., Loveland, J., Zuckerman, M., Moshesh, P., Britz, R., and Botha, J.
- Subjects
- *
GENETIC carriers , *LIVER transplantation , *MAPLE syrup urine disease , *INFANT diseases , *PHYSIOLOGICAL stress - Abstract
Liver transplantation is an accepted treatment modality in the management of MSUD. To our knowledge, ours is only the second successful case to date of a patient with MSUD receiving an allograft from an RLD who is a heterozygous carrier for the disease. In view of the worldwide shortage of available organs for transplantation, heterozygote to homozygote transplantation in the setting of MSUD may provide a viable alternative for those awaiting transplantation. We report on the case of a two-yr-old infant with MSUD, who received a left lateral segment (segments II and III) liver transplant from his mother, a heterozygote carrier of one of the three abnormal genes implicated in MSUD. Post-operative BCAA levels normalized in our patient and remained so on an unrestricted protein diet and during times of physiological stress. To date, this is only the second case of a successful RLD liver transplant in a child with MSUD. Preliminary results indicate that RLD liver transplants are at least equivalent to deceased donor liver transplants in the treatment of MSUD, although longer term follow-up is required. Heterozygote to homozygote RLD transplant in patients with MSUD presents a new pool of potential liver donors. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
98. Ruthenium nanoparticles supported over carbon thin film catalyst synthesized by pulsed laser deposition for hydrogen production from ammonia borane.
- Author
-
Fernandes, R., Patel, N., Edla, R., Bazzanella, N., Kothari, D.C., and Miotello, A.
- Subjects
- *
RUTHENIUM compounds , *NANOPARTICLES , *HYDROGEN production , *AMMONIA , *PULSED laser deposition , *POROUS materials - Abstract
Ruthenium nanoparticles (NPs) supported over carbon thin films (Ru/C thin films) catalysts were synthesized by pulsed laser deposition and used as catalysts for hydrolysis of ammonia borane (AB). Highly irregular and porous carbon films with high surface area were deposited by varying Ar gas pressures during the deposition. By taking the advantage of phase explosion phenomena, occurring at high laser fluence, the surface of the carbon films were decorated with crystalline Ru NPs with size below ∼10 nm. Ru/C thin film catalyst produced H 2 with 6 times higher H 2 generation rate as compared to unsupported Ru NPs assembled film, and with a high turnover frequency value of 70.5 mol H 2 mol −1 Ru min −1 . A combination of morphological features and high content of sp 2 bonded C atoms provides good dispersion of Ru NPs over a large surface area. Both these features contribute in generating large number of active sites leading to the increase in catalytic efficiency. A possibility of using the present form of catalyst as an ON/OFF switch for H 2 production was also tested. Although the catalytic activity decreased with the number of hydrolysis cycles, Ru/C thin film catalyst was able to generate the expected amount of H 2 gas in each cycle when it was reused several times. The observed low activation energy (∼28 kJ mol −1 ) and high H 2 generation rate (15.5 L H 2 min −1 g −1 of Ru) by hydrolysis of AB suggest that Ru/C thin film catalyst is highly efficient. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
99. Would you choose an academic career? Views of current dental clinical academic trainees.
- Author
-
Patel, N. and Petersen, H. J.
- Subjects
- *
DENTAL care , *DENTAL education , *DENTAL health education , *DENTISTS , *DENTAL surveys - Abstract
Objective To determine the views of current dental clinical academic trainees regarding their current posts.Design Online questionnaire emailed to 51 dental academic trainees. Survey results were collected over a six-week period. Eighteen closed statement questions were included using a five-point scale from 'strongly agree' to 'strongly disagree'. All questions had a section for open text comments.Results The response rate for the survey was 73%. A total of 38% were male and 62% female. Just under half of the sample (43%) had a higher teaching qualification. The majority of trainees were from oral surgery (22%), closely followed by restorative and dental public health (both 14%). The main reason trainees stated for choosing an academic post was to be involved in research (68%). The majority of dental clinical academic trainees would recommend a career in academia.Conclusion The majority of dentistry's academic trainees (73%) would recommend an academic career to their peers, a positive change in the culture of modern clinical academia. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
100. Analyzing the dynamics and inter-linkages of carbon and water fluxes in subtropical pine (Pinus roxburghii) ecosystem.
- Author
-
Singh, Nilendu, Patel, N. R., Bhattacharya, B. K., Soni, Prafulla, Parida, B. R., and Parihar, J. S.
- Subjects
- *
CHIR pine , *FOREST canopies , *ECOSYSTEMS , *CARBON , *EVAPOTRANSPIRATION , *MICROMETEOROLOGY - Abstract
The carbon and water fluxes are key aspects of ecosystem functions. Their coupling processes are complicated over terrestrial ecosystems. To understand the seasonal dynamics and coupling mechanism between these fluxes in deciduous subtropical coniferous vegetation in the western Himalayas, the present study involved systematic and concurrent measurements of micrometeorological variables and ecophysiological characteristics within a uniformly distributed young pine forest ecosystem at Forest Research Institute, India. Micrometeorological data were measured continuously for a 14-month period along with key ecophysiological measurements during a growth cycle (2010-2011). These measurements allowed an examination of daytime net canopy assimilation (Cnar), evapotranspiration (ET), light use efficiency (LUE), and water use efficiency (WUE) of this coniferous ecosystem. Results showed that daily variations of ET, Cnar, LUE and WUE were strong functions of temperature and vapour pressure deficit (VPD) but within optimal limits, while these efficiency terms had a close relationship with LAI dynamics and phenology on the seasonal scale. ET being the principal component of water balance (~50% of rainfall), varied between 0.7 and 4.2 mm d-1 depending on LAI and seasonal cycle. It was primarily driven by evaporative demand (VPD) (R² = 0.696, P < 0.001) and air temperature (R² = 0.92, P < 0.001) in addition to radiation and PAR. Significant and stronger correlation of ET against VPD as compared to soil water content (R² = 0.35) in pine ecosystem is indicative of dominant role of stomatal control. The seasonal course of Cnar (peak in post-monsoon and minimum during winter) followed the LAI dynamics except during monsoon. The Cnar of pine varied between 1.2 and 10.5 μmol CO2 m-2 s-1 while that of understory (Lantana camara) varied between 3.7 and 17.3 μmol CO2 m-2 s-1. Pooled data over the seasons showed significant linear relation between Cnar and ET or evaporative fraction. The degree of coupling between water and carbon exchange was strongest in the post-monsoon and spring seasons, and weaker during winter and monsoon seasons. A remarkable strong link between resource use efficiencies (WUE and LUE) was observed particularly in the dry season. This study highlights specifically the response of carbon and water exchange to environmental conditions that would help in forest management by optimizing water resource use. The optimal mix of resource use efficiencies may be the ecophysiological reason of pine ingression into higher reaches of oak forests in the western Himalaya. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.