38 research outputs found
Cold-Active Enzymes and Their Potential Industrial Applications—A Review
More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes
Cold-Active Enzymes and Their Potential Industrial Applications—A Review
More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes
Interplay between Side Chain Density and Polymer Alignment: Two Competing Strategies for Enhancing the Thermoelectric Performance of P3HT Analogues
A series of polythiophenes with varying side chain density was synthesized, and their electrical and thermoelectric properties were investigated. Aligned and non-aligned thin films of the polymers were characterized in the neutral and chemically doped states. Optical and diffraction measurements revealed an overall lower order in the thin films with lower side chain density, also confirmed using polarized optical experiments on aligned thin films. However, upon doping the non-aligned films, a sixfold increase in electrical conductivity was observed for the polythiophene with the lowest side chain density compared to poly(3-hexylthiophene) (P3HT). We found that the improvement in conductivity was not due to a larger charge carrier density but an increase in charge carrier mobility after doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). On the other hand, doped aligned films did not show the same trend; lower side chain density instead led to a lower conductivity and Seebeck coefficient compared to those for P3HT. This was attributed to the poorer alignment of the polymer thin films with lower side chain density. The study demonstrates that optimizing side chain density is a synthetically simple and effective way to improve electrical conductivity in polythiophene films relevant to thermoelectric applications
VPR-Bench: An Open-Source Visual Place Recognition Evaluation Framework with Quantifiable Viewpoint and Appearance Change
Visual place recognition (VPR) is the process of recognising a previously visited place using visual information, often under varying appearance conditions and viewpoint changes and with computational constraints. VPR is related to the concepts of localisation, loop closure, image retrieval and is a critical component of many autonomous navigation systems ranging from autonomous vehicles to drones and computer vision systems. While the concept of place recognition has been around for many years, VPR research has grown rapidly as a field over the past decade due to improving camera hardware and its potential for deep learning-based techniques, and has become a widely studied topic in both the computer vision and robotics communities. This growth however has led to fragmentation and a lack of standardisation in the field, especially concerning performance evaluation. Moreover, the notion of viewpoint and illumination invariance of VPR techniques has largely been assessed qualitatively and hence ambiguously in the past. In this paper, we address these gaps through a new comprehensive open-source framework for assessing the performance of VPR techniques, dubbed “VPR-Bench”. VPR-Bench (Open-sourced at: https://github.com/MubarizZaffar/VPR-Bench) introduces two much-needed capabilities for VPR researchers: firstly, it contains a benchmark of 12 fully-integrated datasets and 10 VPR techniques, and secondly, it integrates a comprehensive variation-quantified dataset for quantifying viewpoint and illumination invariance. We apply and analyse popular evaluation metrics for VPR from both the computer vision and robotics communities, and discuss how these different metrics complement and/or replace each other, depending upon the underlying applications and system requirements. Our analysis reveals that no universal SOTA VPR technique exists, since: (a) state-of-the-art (SOTA) performance is achieved by 8 out of the 10 techniques on at least one dataset, (b) SOTA technique in one community does not necessarily yield SOTA performance in the other given the differences in datasets and metrics. Furthermore, we identify key open challenges since: (c) all 10 techniques suffer greatly in perceptually-aliased and less-structured environments, (d) all techniques suffer from viewpoint variance where lateral change has less effect than 3D change, and (e) directional illumination change has more adverse effects on matching confidence than uniform illumination change. We also present detailed meta-analyses regarding the roles of varying ground-truths, platforms, application requirements and technique parameters. Finally, VPR-Bench provides a unified implementation to deploy these VPR techniques, metrics and datasets, and is extensible through templates
SMAD4 - Molecular gladiator of the TGF-β signaling is trampled upon by mutational insufficiency in colorectal carcinoma of Kashmiri population: an analysis with relation to KRAS proto-oncogene
<p>Abstract</p> <p>Background</p> <p>The development and progression of colorectal cancer has been extensively studied and the genes responsible have been well characterized. However the correlation between the <it>SMAD4 </it>gene mutations with <it>KRAS </it>mutant status has not been explored by many studies so far. Here, in this study we aimed to investigate the role of <it>SMAD4 </it>gene aberrations in the pathogenesis of CRC in Kashmir valley and to correlate it with various clinicopathological variables and <it>KRAS </it>mutant genotype.</p> <p>Methods</p> <p>We examined the paired tumor and normal tissue specimens of 86 CRC patients for the occurrence of aberrations in MCR region of <it>SMAD4 </it>and exon 1 of <it>KRAS </it>by PCR-SSCP and/or PCR-Direct sequencing.</p> <p>Results</p> <p>The overall mutation rate of mutation cluster region (MCR) region of <it>SMAD4 </it>gene among 86 patients was 18.6% (16 of 86). 68.75% (11/16) of the <it>SMAD4 </it>gene mutants were found to have mutations in <it>KRAS </it>gene as well. The association between the <it>KRAS </it>mutant genotype with <it>SMAD4 </it>mutants was found to be significant (P =< 0.05). Further more, we found a significant association of tumor location, tumor grade, node status, occupational exposure to pesticides and bleeding PR/Constipation with the mutation status of the <it>SMAD4 </it>gene (P =< 0.05).</p> <p>Conclusion</p> <p>Our study suggests that <it>SMAD4 </it>gene aberrations are the common event in CRC development but play a differential role in the progression of CRC in higher tumor grade (C+D) and its association with the <it>KRAS </it>mutant status suggest that these two molecules together are responsible for the progression of the tumor to higher/advanced stage.</p
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Technical Evaluation of Ionic Liquid-Extractive Processing of Ultra Low Sulfur Diesel Fuel
© 2015 American Chemical Society. Recent trends in legislation across the world are aimed toward the reduction of the levels of sulfur in fuel oils to less than 10 ppm (ultra low sulfur diesel, ULSD) due to its toxic and environmental effects. Hydrodesulfurization (HDS) is the current method used for desulfurization and faces technical challenges, due to the extreme conditions and energy consumption necessary to reach low sulfur levels. Recently, ionic liquid (IL) technology has been proposed as a possible solution toward achieving ULSD. ILs represent a new class of "green" solvents that are gaining popularity due to their favorable properties and have recently been shown to be effective extractants for desulfurization on a laboratory scale. In this work, the feasibility of industrial scale IL-extractive processing of ULSD has been examined via the simulation and optimization of a conceptual process in ASPEN Plus. The widely used [Cnmim] [NTF2] series of ionic liquids have been employed, due to their favorable properties and the availability of experimental data in literature. User-defined ionic liquid components have been created within ASPEN Plus, incorporating several thermodynamic and physical property parameters derived from literature, to allow the process to be simulated via the UNIFAC thermodynamic method. On the basis of the technical analysis, it is proposed that the most feasible process configuration consists of HDS as a preliminary treatment, followed by IL extraction as intermediate treatment to reduce the sulfur content to 50 ppm, with adsorption as the final treatment to achieve ULSD levels
A Numerical Investigation of Nanocomposite of Copper and Titanium Dioxide in Water Based Fluid Influenced by Instigated Magnetic Region
Cadmium-induced ultramorphological and physiological changes in leaves of two transgenic cotton cultivars and their wild relative
The present study describes cadmium-induced alterations in the leaves as well as at the whole plant level in two transgenic cotton cultivars (BR001 and GK30) and their wild relative (Coker 312) using both ultramorphological and physiological indices. With elevated levels of Cd (i.e. 10, 100, 1000 μM), the mean lengths of root, stem and leaf and leaf width as well as their fresh and dry biomasses linearly decreased over their respective controls. Moreover, root, stem and leaf water absorption capacities progressively stimulated, which were high in leaves followed by roots and stems. BR001 accumulated more cadmium followed by GK30 and Coker 312. Root and shoot cadmium uptakes were significantly and directly correlated with each other as well as with leaf, stem and root water absorption capacities. The ultrastructural modifications in leaf mesophyll cells were triggered with increase in Cd stress regime. They were more obvious in BR001 followed by GK30 and Coker 312. Changes in morphology of chloroplast, increase in number and size of starch grains as well as increase in number of plastoglobuli were the noticed qualitative effects of Cd on photosynthetic organ. Cd in the form of electron dense granules could be seen inside the vacuoles and attached to the cell walls in all these cultivars. From the present experiment, it can be well established that both apoplastic and symplastic bindings are involved in Cd detoxification in these cultivars. Absence of tonoplast invagination reveals that Cd toxic levels did not cause water stress in any cultivars. Additionally, these cultivars possess differential capabilities towards Cd accumulation and its sequestration