316 research outputs found
Generalized fuzzy modified distribution method for generalized fuzzy transportation problem
In this paper, a new approach is proposed to solve Generalized fuzzy transportation problem. Here for the initial solution,Generalized fuzzy Vogel’s approximation method is preferred and to find the optimum solution a new approach, Generalized fuzzy modified distribution method is developed. This new approach is applied to a numerical example and it works well
Implementation of a new third order weighted Runge-Kutta formula based on Centroidal Mean for solving stiff initial value problems
A new third order weighted Runge-Kutta formula based on Centroidal Mean(CeM) is derived and implemented. To illustrate the effectiveness of the method, a stiff problem has been chosen and compared with the classical fourth order Runge-Kutta method and the third order weighted Runge-Kutta method based on Contraharmonic Mean(CoH). The stability of the new method is analysed. The investigation undertaken in the study reveals that the third order RK method based on CeM suits very well and indicates that this method is superior compared to the other methods discussed for the stiff initial value problems
Uniaxial stress studies of the Be pair bound exciton absorption spectrum in silicon
The authors report the results of preliminary uniaxial stress studies of the beryllium pair isoelectronic bound exciton absorption spectrum in silicon. The results confirm that the exciton behaves as an isoelectronic acceptor
Dietary influences on lutein pigments and carcass fat quality in wethers of different maturity types
The aim of this research was to study the effect of high-maize diets and pelleting on the accumulation of lutein pigments and appearance of the subcutaneous fat in Dorper and SA Mutton Merino wethers. High and medium energy maize diets were fed to Dorper and SA Mutton Merino wethers from an initial live weight of ca. 21 kg to a target weight of 43 kg. Fat colour and firmness were evaluated subjectively on a 5-point scale. Samples of the subcutaneous fat and feed were collected for fatty acid and lutein analyses. Loin samples (L1-L6) were oven-roasted and fat characteristics evaluated by a trained sensory panel. The concentrations of lutein pigments and total long-chain fatty acids were influenced mainly by the fattening period (p<0.05) and pelleting of the diets (p<0.05). Lutein concentrations increased during longer fattening periods and resulted in lower colour scores for subcutaneous fat. Neither breed nor the maize content of the diet significantly affected the concentration of lutein in the subcutaneous fat. Lutein concentrations resulted in lower subjective colour scores (p<0.05) and improved the aroma of lamb during carving (p<0.05). The present results suggest that the 'unacceptable' lutein pigments contribute to the typical aroma of lamb.Die doel van die studie was om die invloed van hoe mielie-diete en verpilling van
hoe mielie-diete op die aansameling van luteinpigmente en voorkoms van die subkutanevet
van Dorper en SA Vleismerino hamels te bestudeer. Hoe en medium
energie mielie-diete is aan Dorper en SA Vleismerino hamels vanaf ca. 21 kg tot
teikenmassas van 37 en 43 kg gevoer. Onderhuidse vetmonsters en voermonsters
is versamel vir vetsuur- en luteinontledings. Subkutanevet-eienskappe is subjektief
geevalueer op 'n 5-punt skaal. Monsters van die linker lende (L 1-L6) is geoondbraai
en vet-eienskappe is sintuiglik geevalueer deur 'n opgeleide proepaneel. Die
konsentrasies van lutein pigmente en totale langketting-vetsure is beinvloed deur
die tydperk van vetmesting (p<0.05) en die verpilling van die dieet (p<0.05). Luteinkonsentrasies
het verhoog tydens langer vetmestingsperiodes terwyl die kleur van
die subkutane vet verswak het. Die ras en vlak van mieliemeel-insluiting in die dieet
het geen betekenisvolle invloed gehad op die konsentrasies van lutein in die subkutane
vet nie. Die konsentrasie van luteinpigmente het die subjektiewe kleurtellings
verlaag (p<0.05) en aroma tydens voorsny verbeter (p<0.05). Die huidige
resultate dui daarop dat 'n klein hoeveelheid van die 'onaanvaarbare' luteinpigmente
bydra tot die tipiese aroma van lamsvleis.https://www.sasas.co.za/resources/sa-journal-animal-sciencehj2020Animal and Wildlife Science
Strategies to build a positive and inclusive Antarctic field work environment
Support from National Science Foundation (NSF: Grants 1738913, 1738896, 1738942, 1738992, 1738896, 1738934) and Natural Environment Research Council (NERC: Grants NE/S006788/1, NE/S006605/1, NE/S00677X/1). This research was supported in part by the NOAA cooperative agreement NA17OAR4320101. Logistics provided by NSF-U.S. Antarctic Program and NERC-British Antarctic Survey. ITGC Contribution No. ITGC-084.To increase inclusivity, diversity, equity and accessibility in Antarctic science, we must build more positive and inclusive Antarctic field work environments. The International Thwaites Glacier Collaboration (ITGC) has engaged in efforts to contribute to that goal through a variety of activities since 2018, including creating an open-access 'Field and Ship Best Practices' guide, engaging in pre-field season team dynamics meetings, and surveying post-field season reflections and experiences. We report specific actions taken by ITGC and their outcomes. We found that strong and supported early career researchers brought new and important perspectives regarding strategies for transforming culture. We discovered that engaged and involved senior leadership was also critical for expanding participation and securing funding to support efforts. Pre-field discussions involving all field team members were particularly helpful for setting expectations, improving sense of belonging, describing field work best practices, and co-creating a positive work culture.Publisher PDFPeer reviewe
Clinical endpoints for the study of geographic atrophy secondary to age-related macular degeneration
Purpose: To summarize the recent literature describing the application of modern technologies in the study of patients with geographic atrophy (GA) secondary to age-related macular degeneration. Methods: Review of the literature describing the terms and definitions used to describe GA, imaging modalities used to capture and measure GA, and the tests of visual function and functional deficits that occur in patients with GA. Results: In this paper, we describe the evolution of the definitions used to describe GA. We compare imaging modalities used in the characterization of GA, report on the sensitivity and specificity of the techniques where data exist, and describe the correlations between these various modes of capturing the presence of GA. We review the functional tests that have been used in patients with GA, and critically examine their ability to detect and quantify visual deficits. Conclusion: Ophthalmologists and retina specialists now have a wide range of assessments available for the functional and anatomic characterization of GA in patients with age-related macular degeneration. To date, studies have been limited by their unimodal approach, and we recommend that future studies of GA use multimodal imaging. We also suggest strategies for the optimal functional testing of patients with GA
An Immunocompetent Mouse Model of HPV16(+) Head and Neck Squamous Cell Carcinoma
The incidence of human papilloma virus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) is increasing and implicated in more than 60% of all oropharyngeal carcinomas (OPSCCs). Although whole-genome, transcriptome, and proteome analyses have identified altered signaling pathways in HPV-induced HNSCCs, additional tools are needed to investigate the unique pathobiology of OPSCC. Herein, bioinformatics analyses of human HPV(+) HNSCCs revealed that all tumors express full-length E6 and identified molecular subtypes based on relative E6 and E7 expression levels. To recapitulate the levels, stoichiometric ratios, and anatomic location of E6/E7 expression, we generated a genetically engineered mouse model whereby balanced expression of E6/E7 is directed to the oropharyngeal epithelium. The addition of a mutant PIK3CAE545K allele leads to the rapid development of pre-malignant lesions marked by immune cell accumulation, and a subset of these lesions progress to OPSCC. This mouse provides a faithful immunocompetent model for testing treatments and investigating mechanisms of immunosuppression
Observations of glyoxal and formaldehyde as metrics for the anthropogenic impact on rural photochemistry
We present simultaneous fast, in-situ measurements of formaldehyde and glyoxal from two rural campaigns, BEARPEX 2009 and BEACHON-ROCS, both located in Pinus Ponderosa forests with emissions dominated by biogenic volatile organic compounds (VOCs). Despite considerable variability in the formaldehyde and glyoxal concentrations, the ratio of glyoxal to formaldehyde, R<sub>GF</sub>, displayed a very regular diurnal cycle over nearly 2 weeks of measurements. The only deviations in R<sub>GF</sub> were toward higher values and were the result of a biomass burning event during BEARPEX 2009 and very fresh anthropogenic influence during BEACHON-ROCS. Other rapid changes in glyoxal and formaldehyde concentrations have hardly any affect on R<sub>GF</sub> and could reflect transitions between low and high NO regimes. The trend of increased R<sub>GF</sub> from both anthropogenic reactive VOC mixtures and biomass burning compared to biogenic reactive VOC mixtures is robust due to the short timescales over which the observed changes in R<sub>GF</sub> occurred. Satellite retrievals, which suggest higher R<sub>GF</sub> for biogenic areas, are in contrast to our observed trends. It remains important to address this discrepancy, especially in view of the importance of satellite retrievals and in situ measurements for model comparison. In addition, we propose that R<sub>GF</sub> represents a useful metric for biogenic or anthropogenic reactive VOC mixtures and, in combination with absolute concentrations of glyoxal and formaldehyde, furthermore represents a useful metric for the extent of anthropogenic influence on overall reactive VOC processing via NO<sub>x</sub>. In particular, R<sub>GF</sub> yields information about not simply the VOCs dominating reactivity in an airmass, but the VOC processing itself that is directly coupled to ozone and secondary organic aerosol production
Reparative cell therapy for the heart: critical internal appraisal of the field in response to recent controversies
The concept that cell-based repair of myocardial injury might be possible was introduced almost two decades ago; however, the field of cardiovascular reparative medicine has been criticized as translation to clinically effective approaches has been slow. The recent retraction of a series of papers has further impacted perception of this area of research. As researchers, clinicians, and teachers in this field, we felt it incumbent to critically appraise the current state of cardiac cell repair, determine what can be learned from past mistakes, and formulate best practices for future work. This special communication summarizes an introspective assessment of what has fallen short, how to prevent similar issues, and how the field might best move forward in the service of science and patients.Cardiolog
Grading immunohistochemical markers p16INK4a and HPV E4 identifies productive and transforming lesions caused by low- and high-risk HPV within high-grade anal squamous intraepithelial lesions
Objectives: Because current guidelines recognise high-grade anal squamous intraepithelial lesions (HSILs) and low-grade SILs (LSILs), and recommend treatment of all HSILs although not all progress to cancer, this study aims to distinguish transforming and productive HSILs by grading immunohistochemical (IHC) biomarkers p16INK 4a (p16) and E4 in low-risk human papillomavirus (lrHPV) and high-risk (hr)HPV-associated SILs as a potential basis for more selective treatment. Methods: Immunostaining for p16 and HPV E4 was performed and graded in 183 biopsies from 108 HIV-positive men who have sex with men. The causative HPV genotype of the worst lesion was identified using the HPV SPF10-PCR-DEIA-LiPA25 version 1 system, with laser capture microdissection for multiple infections. The worst lesions were scored for p16 (0–4) to identify activity of the hrHPV E7 gene, and panHPV E4 (0–2) to mark HPV production and life cycle completion. Results: There were 37 normal biopsies, 60 LSILs and 86 HSILs, with 85% of LSILs caused by lrHPV and 93% of HSILs by hrHPV. No normal biopsy showed E4, but 43% of LSILs and 37% of HSILs were E4 positive. No differences in E4 positivity rates were found between lrHPV and hrHPV lesions. Most of the lesions caused by lrHPV (90%) showed very extensive patchy p16 staining; p16 grade in HSILs was variable, with frequency of productive HPV infection dropping with increasing p16 grade. Conclusions: Combined p16/E4 IHC identifies productive and nonproductive HSILs associated with hrHPV within the group of HSILs defined by the Lower Anogenital Squamous Terminology recommendations. This opens the possibility of investigating selective treatment of advanced transforming HSILs caused by hrHPV, and a ‘wait and see’ policy for productive HSILs. What's already known about this topic?. For preventing anal cancer in high-risk populations, all patients with high-grade squamous intraepithelial lesions (HSILs) are treated, even though this group of lesions is heterogeneous, the histology is variable and regression is frequent. What does this study add?. By adding human papillomavirus (HPV) E4 immunohistochemistry to p16 INK4a (p16), and grading expression of both markers, different biomarker expression patterns that reflect the heterogeneity of HSILs can be identified. Moreover, p16/E4 staining can separate high-risk HPV-associated HSILs into productive and more advanced transforming lesions, providing a potential basis for selective treatment
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