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The microsomal metabolism of phenol (11 °C) over an annual reproductive cycle from June to December was studied using fall spawning adult brook trout (Salvelinus fontinalis). Hepatic microsomes were isolated from three male and three female fish each month. Incubations were optimized for time, cofactor concentration, pH, and microsomal protein concentration. The formation of phase I ring-hydroxylation metabolites, i.e., hydroquinone (HQ) and catechol (CAT), was quantified by HPLC with dual-channel electrochemical detection. Sample preparation and chromatographic conditions were optimized to achieve the separation and sensitivity required for the analysis of these labile products. Biotransformation of phenol over a range of substrate concentrations (1 to 150 mM) was quantified for the calculation of Michaelis–Menten constants (Km and Vmax) for each month. Results indicate a nearly equal production of HQ and CAT among males and females in late June. At the peak of maturity in October, there was an approximate ten-fold greater production of ring-hydroxylation metabolites noted in females in comparison with males on a total liver basis. In vitro phase II biotransformation of phenol glucuronidation was assessed by determining the Michaelis–Menten constants (Km, Vmax) using brook trout hepatic microsomes over a range of substrate concentrations (1 to 60 mM). Initially, there were no significant differences in the glucuronide rate of formation (pmol/min/mg protein) or total capacity (nmol/min/liver) between females and males. At the peak of maturation, the maximum rate of glucuronide formation was 4-fold less in females; however, the total capacity was 2-fold less in females due to the increased liver size in the females. The alterations in biotransformation coincided with increases in the hepatic and gonadal somatic indices and with changes in plasma hormone concentrations. These experiments provide insight into the metabolic deactivation of xenobiotics and to provide data for the prediction of altered hepatic biotransformation rates and pathways during the reproductive cycle. [ABSTRACT FROM AUTHOR]

The objective of this research is to investigate the effect of customer involvement in different stages of the new product development process and absorptive capacity on the growth performance of startups. In this paper, the linear regression was utilised to analyse the empirical data collected from 152 startups in Vietnam. Results showed that customer involvement has a positive impact on startup growth. Particularly, startups who involve customers more intensively in the ideation stage will yield better growth than those involving customers in the development and commercialisation. The next finding is about knowledge absorptive capacity whose four processes affect startup growth differently. The analysed data revealed that only knowledge acquisition and knowledge exploitation have a significant positive impact on the performance of startups. Other processes of absorptive capacity, which are knowledge assimilation and transformation, have no contribution to performance. Based on results, some recommendations to enhance the startups' performance are proposed. [ABSTRACT FROM AUTHOR]

Temperature is a key parameter that influences the uptake and subsequent utilization of nitrogen by plants. Both suboptimal and supraoptimal temperatures can impair nutrient uptake. The close relatives of bread wheat provide a possible source for breeders to increase stress tolerance. The effect of the increasing temperature (5, 10, 15, 20 and 30 °C) on nitrate uptake and metabolism in five modern spring cultivars of bread wheat (Triticum aestivum L.) and two cultivars of emmer wheat (Triticum dicoccon Schrank), was monitored. Wheat plants were grown under controlled conditions in hydroponics. The parameters of Michaelis-Menten kinetics, maximum uptake rate (Vmax), the Michaelis constant (Km) and selected characteristics of nitrate metabolism, the activity of nitrate reductase (NR) and contents of nitrate in leaves were observed. The effect of temperature was significant for all studied traits except Km, while the cultivar factor was significant for Vmax, Km, NR and root/shoot ratio (R/S). Emmer wheat cultivar Rudico had significantly higher Vmax at 5, 15, 20 and 30 °C than all bread wheat cultivars, on average 7.07, in comparison with 4.09-4.43 μmol NO3-/g FW/h in bread wheat cultivars. Emmer wheat Rudico and Tapiruz had significantly higher Km (on average, 41.59 and 47.22 μM NO3-) than bread wheat cultivars (27.59-33.44 μM NO3-). Differences in the studied kinetic parameters of nitrate uptake offer the possibility of using T. dicoccon genotypes in breeding for better nitrogen use efficiency.

Blood is important evidence that can assist an investigator in solving a crime. It connects the suspect to a crime and aid in the reconstruction of the crime scene. Criminals frequently attempt to wipe away blood stained evidence at a crime scene. These efforts may result in the modification or partial or total elimination of blood on the stained parts. Numerous presumptive tests are employed to identify bloodstains on floor surfaces since they are frequently cleansed after a crime using various surfactants. However, the traces of stains remain there and if analysed with appropriate reagents will give conclusive results. In This study Blood-stained floor surfaces were cleaned using a commercially available and widely used floor cleaners and After repeated washings, the Kastle-Meyer (KM), Leucomalachite green (LMG), and Tetra methylbenzidine (TMB) tests were employed to determine the presence of blood on these surfaces, and their sensitivity were assessed, this study will help the forensic investigator to select the appropriate reagents for detection of blood stains on the various washed floor surfaces and effectiveness of reagents for detection of blood stains washed with various floor cleaners. [ABSTRACT FROM AUTHOR]

Maintaining essential skills is a challenge for organizations today. This study investigates the relationship between Knowledge Management (KM) and Quality of Work Life (QWL) to address the lack of exploration in this domain. Our goal is a comprehensive literature review to reveal the impact of KM practices on QWL. By employing a qualitative methodology, our study concludes that effective implementation of KM strategies is critical in influencing positive QWL outcomes. We propose essential strategies for optimal KM integration in the workplace.

The medical field now needs more novel drugs to treat obesity and type-2 diabetes mellitus (T2D) than ever before. Obesity and T2D are both characterized by resistance to the hormones leptin and insulin. PTP-1B is a promising target for drug growth, as strong genetic, pharmacological, and biochemical evidence points to the possibility of treating diabetes and obesity by blocking the PTP-1B enzyme. Studies have also found that PTP-1B is overexpressed in patients with diabetes and obesity, suggesting that inhibiting PTP-1B may be a useful technique in their care. There are no clinically used PTP-1B inhibitors, despite the fact that numerous naturally occurring PTP-1B inhibitors have demonstrated great therapeutic promise. This is most likely due to their low activity or lack of selectivity. It is still important to look for more effective and focused PTP-1B inhibitors. A few organovanadium metal complexes were synthesized and characterized, and binding studies on vanadium complexes with PTP-B were also performed using fluorescence emission spectroscopy. Additionally, we theoretically (molecular modeling) and experimentally (enzyme kinetics) examined the PTP-1B inhibitory effects of these vanadium metal complexes and found that they have excellent PTP-1B inhibitory properties. [ABSTRACT FROM AUTHOR]

Alpha-amylase is one of the most widely used enzymes in the starch industry. However, industrial application of soluble alpha-amylase is hampered by changes in pH and temperature (adverse effects on enzyme stability) and activity loss, leading to higher costs. Immobilization of alpha-amylase is an efficient strategy to reduce the enzyme losing and subsequently reduces costs in this regard. Alpha-amylases are immobilized by adsorption, entrapment, covalent attachment, and cross-linking. A barrier in alpha-amylase immobilization is the large size of its substrate, namely amylose and amylopectin. Most of these immobilization methods decrease the affinity of the enzyme for its substrate as well as the maximum rate of reaction (Vmax). This review aims to study different aspects of alpha-amylase including enzyme activity, applications, structure, starch, immobilization methods, and immobilization’s obstacles to improve alpha-amylase efficiency in the industry and also lowering the costs related to providing this enzyme.

Maintaining essential skills is a challenge for organizations today. This study investigates the relationship between Knowledge Management (KM) and Quality of Work Life (QWL) to address the lack of exploration in this domain. Our goal is a comprehensive literature review to reveal the impact of KM practices on QWL. By employing a qualitative methodology, our study concludes that effective implementation of KM strategies is critical in influencing positive QWL outcomes. We propose essential strategies for optimal KM integration in the workplace. [ABSTRACT FROM AUTHOR]

Abstract:This Research aims to study The Unpublished km stela, As it has not been investigated nor studied in a comprehensive analytical by Researchers, This Stela appears to be rectangular and it has a top that takes the shape of the Egyptian cornice, and it is preserved in the Egyptian Museum in Cairo and bears the number (CG 20573), The Stela is divided into three recorded texts and recorded scenes.Where the first record contained the main text of the Stela, which is a formula for offering sacrifices topped by the shape of the Egyptian cornice that crowns the top of the stela, and this record was divided into three written sections with different directions as shown in the linear study, while only one word was recorded in the second record Behind the deceased and it is a continuation of the text recorded in the first record, while the third record contains separate phrases written either vertically or horizontally, some of which were written in front and behind the deceased or above the offering table, or between the offeror's of the owner of the Stela as shown in the written study. As for the scenes recorded on this Stela where it was noticed the presence of some artistic elements and religious symbols that were represented by the offerings, the offering table, the lotus flower, the geese bird, as well as the presence of some shapes of the vessels presented as an offering to the owner of Stela, This stela will be dealt with through a linguistic and artistic analytical study according to the Methodology of the Study through the descriptive and analytical comparative approach, applying the formula and linguistic structures contained in the stela in addition to refuting and analyzing the artistic elements and their symbolic connotations in the ancient Egyptian beliefs, The comparative Historical method also be used to apply the artistic elements and linguistic connotations in order to establish an accurate date for that Stela in question. Key Words: Km stela - Egyptian Museum- Egyptian cornice - offerings- offerings table- The Lotus - Geese.

The distribution of the D2-like dopamine receptor (D2DR) in the cortex and striatum was compared between rats with absence, audiogenic, or combined genetically determined epilepsy and normal Wistar rats by autoradiography. A significantly lower D2DR binding density was observed in the dorsal and ventrolateral aspects of the nucleus accumbens in epileptic vs. non-epileptic rats. Rats with audiogenic epilepsy additionally showed a higher D2DR density in the dorsal striatum and motor and somatosensory cortex and a lower D2DR density in the ventrolateral part of the nucleus accumbens. The findings indicated that a common neuronal circuit is involved in the pathogenesis of both convulsive and nonconvulsive forms of generalized epilepsy. [ABSTRACT FROM AUTHOR]

Abstract Background Complex enzymatic models are required for analyzing kinetic data derived under conditions that may not satisfy the assumptions associated with Michaelis–Menten kinetics. To analyze these data, several software packages have been developed. However, the complexity introduced by these programs is often dispensable when analyzing data conforming to the canonical Michaelis–Menten model. In these cases, the sophisticated routines of these packages become inefficient and unnecessarily intricated for the intended purpose, reason for which most users resort to general-purpose graphing programs. However, this approach, in addition of being time-consuming, is prone to human error, and can lead to misleading estimates of kinetic parameters, particularly when unweighted regression analyses of transformed kinetic data are performed. Results To fill the existing gap between highly specialized and general-purpose software, we have developed an easy-to-use R package, renz, designed for accurate and efficient estimation of enzyme kinetic parameters. The package provides different methods that can be clustered into four categories, depending on whether they are based on data fitting to a single progress curve (evolution of substrate concentration over time) or, alternatively, based on the dependency of initial rates on substrate concentration (differential rate equation). A second criterion to be considered is whether the experimental data need to be manipulated to obtain linear functions or, alternatively, data are directly fitted using non-linear regression analysis. The current program is a cross-platform, free and open-source software that can be obtained from the CRAN repository. The package is accompanied by five vignettes, which are intended to guide users to choose the appropriate method in each case, as well as providing the basic theoretical foundations of each method. These vignettes use real experimental data to illustrate the use of the package utilities. Conclusions renz is a rigorous and yet easy-to-use software devoted to the analysis of kinetic data. This application has been designed to meet the needs of users who are not practicing enzymologists, but who need to accurately estimate the kinetic parameters of enzymes. The current software saves time and minimizes the risk of making mistakes or introducing biases due to uncorrected error propagation effects.

Knowledge sharing is relevant to the success and development of organizations of different natures whose processes are based on information flows. Software development organizations constantly demand technological innovation and face challenges in the market in which they operate. Therefore, they need to manage and share knowledge to achieve innovation and sustainability in the market. This article investigates the influencing factors of knowledge sharing in software development teams. Methodologically, this is exploratory research carried out through a closed questionnaire conducted via chatbot. The article analyses quantitative data from the Knowledge Management (KM) literature. It identifies factors influencing knowledge sharing at the individual and organizational level in software development companies. As contributions, in addition to the discussion of data, the article presents recommendations for KM practices that can deepen knowledge sharing in software development organizations. [ABSTRACT FROM AUTHOR]

Fungal metabolic rates could increase under climate warming but may be counteracted by mechanisms of physiological acclimation and evolutionary adaptation. We hypothesized that Vmax and Km parameters of Neurospora discreta extracellular enzymes would acclimate to warmer temperatures through compensatory mechanisms. We also predicted that evolution under warmer temperatures would alter enzyme parameters and fungal respiration through adaptive mechanisms. In contrast to these predictions, growth at higher temperature (22 °C versus 16 °C) increased the temperature-corrected Vmax of three enzymes. The carbon substrate used for fungal growth (lignin versus sucrose) had a much greater impact on enzyme Vmax than temperature. Following experimental evolution, the enzymatic parameters of Neurospora strains did not adapt to higher temperatures as hypothesized; rather, enzyme Vmax values were unaffected, and respiration rates increased. Together, these results suggest that physiological and evolutionary mechanisms are unlikely to counteract soil carbon losses driven by saprotrophic fungi under climate warming.

Fungal metabolic rates could increase under climate warming but may be counteracted by mechanisms of physiological acclimation and evolutionary adaptation. We hypothesized that Vmax and Km parameters of Neurospora discreta extracellular enzymes would acclimate to warmer temperatures through compensatory mechanisms. We also predicted that evolution under warmer temperatures would alter enzyme parameters and fungal respiration through adaptive mechanisms. In contrast to these predictions, growth at higher temperature (22 °C versus 16 °C) increased the temperature-corrected Vmax of three enzymes. The carbon substrate used for fungal growth (lignin versus sucrose) had a much greater impact on enzyme Vmax than temperature. Following experimental evolution, the enzymatic parameters of Neurospora strains did not adapt to higher temperatures as hypothesized; rather, enzyme Vmax values were unaffected, and respiration rates increased. Together, these results suggest that physiological and evolutionary mechanisms are unlikely to counteract soil carbon losses driven by saprotrophic fungi under climate warming.

The magnitude and direction of carbon cycle feedbacks under climate warming remain uncertain due to insufficient knowledge about the temperature sensitivities of soil microbial processes. Enzymatic rates could increase at higher temperatures, but this response could change over time if soil microbes adapt to warming. We used the Arrhenius relationship, biochemical transition state theory, and thermal physiology theory to predict the responses of extracellular enzyme Vmax and Km to temperature. Based on these concepts, we hypothesized that Vmax and Km would correlate positively with each other and show positive temperature sensitivities. For enzymes from warmer environments, we expected to find lower Vmax , Km , and Km temperature sensitivity but higher Vmax temperature sensitivity. We tested these hypotheses with isolates of the filamentous fungus Neurospora discreta collected from around the globe and with decomposing leaf litter from a warming experiment in Alaskan boreal forest. For Neurospora extracellular enzymes, Vmax Q10 ranged from 1.48 to 2.25, and Km Q10 ranged from 0.71 to 2.80. In agreement with theory, Vmax and Km were positively correlated for some enzymes, and Vmax declined under experimental warming in Alaskan litter. However, the temperature sensitivities of Vmax and Km did not vary as expected with warming. We also found no relationship between temperature sensitivity of Vmax or Km and mean annual temperature of the isolation site for Neurospora strains. Declining Vmax in the Alaskan warming treatment implies a short-term negative feedback to climate change, but the Neurospora results suggest that climate-driven changes in plant inputs and soil properties are important controls on enzyme kinetics in the long term. Our empirical data on enzyme Vmax , Km , and temperature sensitivities should be useful for parameterizing existing biogeochemical models, but they reveal a need to develop new theory on thermal adaptation mechanisms.

ABSTRACT Understanding the kinetics of Zn absorption by roots and its effect on morphology of this organ is relevant for improving crop management, but still poorly studied for common beans. Therefore, an experiment was conducted in a hydroponic system with five initial concentrations of Zn (CZnI): 0.0; 1.0; 4.0; 16.0 and 48.0 µmol L-1. The experiment was installed with plants at V3 stage of development and aliquots of the solution collected over 24 h. The maximum absorption rate (Vmax), Michaelis-Menten constant (Km) and the absorption power (α) increased as a function of CZnI. The minimum concentration of Zn estimated for its absorption (Cmin) was at 0.0028 mg L-1. The influx of Zn (Imax) was higher in higher CZnI, 16,0 µmol L-1. Root length, root volume, root Zn content and Zn absorption efficiency increased with the increase of CZnI. Therefore, the increase of CZnI positively influenced kinetic parameters of root Zn absorption and common bean root morphology, characteristics that favor Zn absorption by roots and improves overall plant nutrition, favoring agronomical biofortification practices for Zn and other nutrients.

Background: Complex enzymatic models are required for analyzing kinetic data derived under conditions that may not satisfy the assumptions associated with Michaelis–Menten kinetics. To analyze these data, several software packages have been developed. However, the complexity introduced by these programs is often dispensable when analyzing data conforming to the canonical Michaelis–Menten model. In these cases, the sophisticated routines of these packages become inefficient and unnecessarily intricated for the intended purpose, reason for which most users resort to general-purpose graphing programs. However, this approach, in addition of being time-consuming, is prone to human error, and can lead to misleading estimates of kinetic parameters, particularly when unweighted regression analyses of transformed kinetic data are performed. Results: To fill the existing gap between highly specialized and general-purpose software, we have developed an easy-to-use R package, renz, designed for accurate and efficient estimation of enzyme kinetic parameters. The package provides different methods that can be clustered into four categories, depending on whether they are based on data fitting to a single progress curve (evolution of substrate concentration over time) or, alternatively, based on the dependency of initial rates on substrate concentration (differential rate equation). A second criterion to be considered is whether the experimental data need to be manipulated to obtain linear functions or, alternatively, data are directly fitted using non-linear regression analysis. The current program is a cross-platform, free and open-source software that can be obtained from the CRAN repository. The package is accompanied by five vignettes, which are intended to guide users to choose the appropriate method in each case, as well as providing the basic theoretical foundations of each method. These vignettes use real experimental data to illustrate the use of the package utilities. Conclusions: renz is a rigorous and yet easy-to-use software devoted to the analysis of kinetic data. This application has been designed to meet the needs of users who are not practicing enzymologists, but who need to accurately estimate the kinetic parameters of enzymes. The current software saves time and minimizes the risk of making mistakes or introducing biases due to uncorrected error propagation effects. [ABSTRACT FROM AUTHOR]

Blended Learning (BL) essentially fuses high-tech digital learning with traditional ones to involve students in "network learning", which helps in transcending physical boundaries. Especially during the ongoing COVID-19 pandemic, BL has been embraced as a realistic possibility to ensure seamless knowledge distribution regardless of time and space. Knowledge Management (KM)-based approaches are typically used to collect, coordinate, and control processes that may be utilised efficiently to both recognise and address customer needs. This study aims to explain how to apply KM techniques within the BL environment to increase educational excellence and quality. We used a quantitative approach, specifically by adopting an online questionnaire circulated to about 272 undergraduate students, primarily from the Department of Information Science and Library Management (ISLM) of the University of Dhaka, Bangladesh. We received completed answers from 74 students; the data gathered were analysed using Statistical Package for the Social Sciences (SPSS) version 20. The findings reveal that KM can be used with BL, especially during crisis times like the one we have today, as it includes integrated tasks and online and e-learning. Finally, the study also proposed an intuitive model for applying BL through KM. Importantly, this study seems to be among the first to examine the students' perceptions about BL and KM integration during a pandemic. Therefore, this research would possibly prompt further research on different aspects of the combined learning process at different universities, especially within Bangladesh. [ABSTRACT FROM AUTHOR]

The volatile profile of ‘Redchief Delicious’ apple (Malus ×domestica Borkh.) fruit was evaluated at 18 time points from 3 weeks before to 8 weeks after onset of autocatalytic ethylene production to capture the dynamics associated with development from mature green to senescent fruit. Minor amounts of ester production began several days before the onset of ethylene production. Ester production rose rapidly as internal ethylene levels increased beyond 22 nmol·L−1 (0.5 µL·L−1). Peak ester production roughly coincided with maximum ethylene synthesis, declining thereafter. Ester production was further evaluated according to the acid- (alkanoate) and alcohol- (alkyl) derived portions of the ester. The maximum rate of production for a given ester tended to occur later in development as the chain length of the alcohol-derived portion declined. The production rate for many esters paralleled the rate of emanation of their respective alcohol substrates, suggesting that availability of the alcohols limits ester production more than availability of the acid substrates. Combining production rates with sensory descriptors and human sensitivity to individual volatiles permitted approximations of aroma sensations likely engendered by the fruit throughout ripening. Overripe and alcoholic sensations are predicted to increase 2 weeks after the initiation of ripening in response to an increase in the production of ethyl esters. Acetate esters predominated, comprising 50% to 80% of esters throughout maturation and ripening, indicating that the substrate acetyl-CoA may be at saturating levels for alcohol acyl transferase (AAT) at the final step of ester formation. Acetate feeding did not enhance ester production, although label from 13C-acetate was extensively incorporated into esters. The data are consistent with the action of multiple AAT isozymes differing in activity and substrate preference. Incorporation of labeled 13C-acetate into precursors of esters, alcohols, and acids, reflected ester biosynthesis via 1- and 2-carbon chain elongation pathways in ripening ‘Redchief Delicious’ apple fruit.

The coronavirus pandemic has compelled academic institutions across the globe to initiate online teaching, impacting thereby the teaching-learning process to undergo a structural change. Among various pedagogical techniques that have been adopted, organizing synchronous classes has been found to be the most beneficial. It simulates the classroom environment, facilitating thereby parallel knowledge dissemination to a broader audience. This study measures the efficacy of synchronous web-based learning during this ongoing pandemic, among postgraduate Library and Information Science (LIS) students of Bangladesh. Using an online questionnaire, a survey was conducted among the postgraduate students of the Department of Information Science Library Management (ISLM) of the University of Dhaka. The results revealed that limitation of internet data, unstable internet, along with power blackouts were some of the primary inhibitors blocking the participants to attend classes online. Finally, this study concludes that as most students do not seem to be ready yet to study in a synchronous delivery mode, it recommends educational institutions in Bangladesh to provide an alternative delivery method, in order to sustain academic excellence in these challenging times.

β-glucosidases (3.2.1.21) are present in all domains of living organisms, and their importance in a number of essential biological processes and industrial applications has been highlighted. They are interesting for biomass conversion because b-glucans are the world's largest source of biomass. For this reason, several fungal β-glucosidases have been investigated. The β-glucosidase gene of Aspergillus fumigatus, as well as its mutants D262E and W263F, were cloned and expressed in Pichia pastoris in this study. Their optimum temperature, pH, glucose tolerance, metal ion effect, and Vmax, km, and kcat were determined. The optimal temperature for recombinant β-glucosidase was 65 °C. For mutant D262E, there is an improvement in pH stability ranging from 4 to 6. As compared to the D262E mutant and recombinant β-glucosidase, mutant W263F showed a higher glucose tolerance and kcat. [ABSTRACT FROM AUTHOR]

Background: Knowledge management (KM) holds a major influence on the effective delivery of services in government departments as it is tactically affiliated to the formation, composition, and sharing of information to prevent 'reinvention of the wheel' by staffs when performing their jobs. However, few government departments within the South African context have implemented formal KM initiatives. Objectives: This research sought to examine the KwaZulu-Natal Department of Public Works (Pietermaritzburg) employees' awareness of any KM initiatives, their benefits, and barriers that are preventing the successful implementation of a formal initiative. Method: A survey research approach was utilised in which structured questionnaires were administered to respondents. Data were analysed using the Statistical Package for the Social Science (SPSS). Results: The research established that KM initiatives are being practiced informally within the Department and there is a reasonably high level of awareness of these initiatives together with the benefits associated with them. The lack of a dedicated unit for KM and KM professionals are some of the barriers to the successful implementation of formal initiatives. Conclusion: The research concluded that the Department is in dire need of a formal KM initiative to reap the potential benefits and improve service delivery. [ABSTRACT FROM AUTHOR]

Population growth, the intensification of human activities, the impact of natural hazards related to water and climate change, directly and indirectly, affect the availability of water resources. This requires rational and sustainable management of water resources. Thus, it is essential to conduct a comprehensive assessment of available water resources based on current and future needs. This assessment involves collecting and processing hydrological data to provide reliable information on water resources' status and evolution. However, the non-availability and lack of hydrological data constrain the process of this assessment. Therefore, we propose in this work to adopt a clustering analysis based-regionalization approach combining multivariate data analysis (PCA) and clustering algorithms (HAC and KM) to delineate watersheds' homogeneous clusters. Clustering analysis produces groups of watersheds based on their similarity which will allow the transfer of data from gauged sites to ungauged sites. At the end of the present study, 6 clusters of watersheds were identified. These identified clusters have their characteristics in terms of surface, perimeter, length of the equivalent rectangle, time of concentration, and land use. Based on result validation indicators (cross-validation approach), the studied catchment areas have been assigned to the clusters that represent them the best. [ABSTRACT FROM AUTHOR]

Background: Knowledge management (KM) holds a major influence on the effective delivery of services in government departments as it is tactically affiliated to the formation, composition, and sharing of information to prevent ‘reinvention of the wheel’ by staffs when performing their jobs. However, few government departments within the South African context have implemented formal KM initiatives. Objectives: This research sought to examine the KwaZulu-Natal Department of Public Works (Pietermaritzburg) employees’ awareness of any KM initiatives, their benefits, and barriers that are preventing the successful implementation of a formal initiative. Method: A survey research approach was utilised in which structured questionnaires were administered to respondents. Data were analysed using the Statistical Package for the Social Science (SPSS). Results: The research established that KM initiatives are being practiced informally within the Department and there is a reasonably high level of awareness of these initiatives together with the benefits associated with them. The lack of a dedicated unit for KM and KM professionals are some of the barriers to the successful implementation of formal initiatives. Conclusion: The research concluded that the Department is in dire need of a formal KM initiative to reap the potential benefits and improve service delivery.

This paper argues that business enterprises in this competitive global market cannot compete and remain sustainable without effective knowledge sharing to improve business intelligence processes. The central argument hinges on the deployment and use of information technology (IT) as strategic tools to promote business decision making through quick business data analysis and dissemination of business ideas across business units and locations. The study reiterated the critical role IT plays in facilitating a culture of organizational learning and knowledge sharing practices. The study utilized surveys and questionnaires that were distributed to 230 small and medium enterprises (SMEs), and both descriptive and inferential statistics were used to present the results. Findings showed that firms are still using one-on-one meeting to share knowledge, while knowledge sharing activities are controlled through a rigid and inflexible process at the top management level, thereby hindering knowledge flow that is crucial for real-time decision making. The advances in IT have not been used advantageously to improve knowledge sharing and to advance business management. The paper concludes that without strong positive correlation between IT infrastructure integration, and communication strategies and knowledge sharing, the SMEs may not be able to compete in a highly competitive knowledge economy. Consequently, they may lose leverage to another competitor with more robust and mature IT infrastructure alignment for sharing business analytics and intelligence efficiently. A technologically driven, open, and informal approach to knowledge sharing for productive and innovative engagement is recommended. Furthermore, the use of IT that can promote agile and real-time knowledge sharing is recommended.

Background: The lactate dehydrogenase C4 (LDH-C4) isoenzyme is an important enzyme involved in metabolic processes that are needed for spermatogenesis and sperm motility. Objectives: This study aims to assess the activity and kinetic parameters (maximum velocity, Vmax and Michaelis constant, Km) of LDH-C4 in fertile and infertile (azoospermia and oligospermia) men in Baghdad City, Iraq. Methods: A total of 120 participants (80 infertile and 40 healthy fertile men) were included in the current study. The patients were sub-grouped into: 40 infertile men with oligospermia, and 40 infertile men with azoospermia. The oligospermia patients were further subdivided into subgroups based on sperm count and motility. Semen samples were obtained by masturbation after 3-5 days abstain for seminal fluid analysis. The microscopic test included the assessment of the count, motility and morphology of the sperms. In addition, the coulometric assay was used for measuring the activity and kinetic parameters of LDH-C4 enzyme. Results: The activity of LDH-C4 is significantly higher in fertile men when compared with infertile subjects (fertile: 403.13±189.90, oligospermia: 110.01±58.13, azoospermia: 39.06±28.15; p≤0.01). Statistically significant differences in LDH-C4 activity were also noted among patients with oligospermia based on sperms count and motility. Based on sperms’ count in patients with oligospermia, a significantly higher LDH-C4 activity (p≤0.01) was noted in those with higher sperm count (10-15 million/ml) when compared to others who have lesser count. Significant elevation in enzyme activity (p≤0.01) was also observed in oligospermia patients with higher percentages of motile sperms when compared with others who have fewer percentages of motile sperms. Moreover, the highest Vmax value (0.483 mmol/L.min) and the lowest Km value (0.39 mmol/L.min) were recorded in fertile men. While, the lowest Vmax value (0.174 mmol/L.min) and the lowest Km value (0.75 mmol/L.min) were detected in azoospermia patients. Conclusions: Our results suggest that LDH-C4 is essential for the count and motility of sperm and may be considered as a therapeutic approach for infertility.

Nitrogen, the most demanded nutrient by coffee plants, has a rate of recovery from the soil of about 50%. Because of that high doses of nitrogenous fertilizers are used to reach high production, and consequently high amounts of N are lost to the environment. Knowing the kinetic parameters of nitrate (NO3-) absorption over the fruit development cycle is important as a mean of achieve more adjusted fertilizer doses and better recovery rates for the N applied as fertilizers. This study aimed determining the kinetic parameters of NO3- absorption in different development stages of fruits from adult coffee plants. The kinetic parameters Vmax and Km were determined in a low production year, at the pinhead (PH), rapid expansion (RE), grain filling (GF), and maturation (MT) stages. One month before each kinetics assay, lateral roots of eight plants were excavated and wrapped into non-woven fabrics grow cylinders filled in with vermiculite to produce absorbent roots. On the assay day, the roots were washed and immersed into a container with 1 L of 90 μmol L−1 NO3- solution. Sampling began one and a half hours after that, and was taken every hour over 7 h. Data on NO3- depletion were used to calculate the absorption kinetic parameters Vmax and Km. In a low production year the Vmax ranged from 0.14 to 0.72 μmol g−1 h−1 in a root fresh matter basis and Km from 6.47 to 50.31 μmol L−1. The Vmax values were highest at the PH and MT stages; the lowest absorption rate was recorded at GF and Km was lowest at RE. As at the RE stage of fruits Vmax shows a positive correlation with grain production, adequate nitrogen availability must be ensured before this phase to not to affect coming coffee production.

Understanding the kinetics of Zn absorption by roots and its effect on morphology of this organ is relevant for improving crop management, but still poorly studied for common beans. Therefore, an experiment was conducted in a hydroponic system with five initial concentrations of Zn (CZnI): 0.0; 1.0; 4.0; 16.0 and 48.0 µmol L-1. The experiment was installed with plants at V3 stage of development and aliquots of the solution collected over 24 h. The maximum absorption rate (Vmax), Michaelis-Menten constant (Km) and the absorption power (a) increased as a function of CZnI. The minimum concentration of Zn estimated for its absorption (Cmin) was at 0.0028 mg L-1. The influx of Zn (Imax) was higher in higher CZnI, 16,0 µmol L-1. Root length, root volume, root Zn content and Zn absorption efficiency increased with the increase of CZnI. Therefore, the increase of CZnI positively influenced kinetic parameters of root Zn absorption and common bean root morphology, characteristics that favor Zn absorption by roots and improves overall plant nutrition, favoring agronomical biofortification practices for Zn and other nutrients. [ABSTRACT FROM AUTHOR]

We are living in the Big Data era, and yet we may have serious troubles when dealing with a handful of kinetic data if we are not properly instructed. The aim of this paper, related to enzyme kinetics, is to illustrate how to determine the Km and Vmax of a michaelian enzyme avoiding the pitfalls in which we often fall. To this end, we will resort to kinetic data obtained by second‐year Biochemistry students during a laboratory experiment using β‐galactosidase as an enzyme model, assayed at different concentrations of its substrate. When these data were analyzed using conventional linear regression of double‐reciprocal plots, the range of Km and Vmax values obtained by different students varied widely. Even worse, some students obtained negative values for the kinetic parameters. Although such a scenario could make us think of a wide inter‐student variability regarding their skills to obtain reliable data, the reality was quite different: when properly analyzed (accounting for error propagation) the data obtained by all the students were good enough to allow a correct estimation of the Km (2.8 ± 0.3 mM) and Vmax (179 ± 27 mM/min) with a reduced intergroup standard deviation. A student‐accessible discussion of the importance of weighted linear regression in biochemical sciences is provided. [ABSTRACT FROM AUTHOR]

Rapid and accurate monitoring of soil organic matter (SOM) content is of great significance for precision fertilization of farmland. However, the SOM retrieval models are mainly established by statistical methods, which have limited application scope and incomplete theoretical foundation. Moreover, the accuracy of the SOM retrieval models remains raised. In this paper, for the first time, a semi-empirical SOM content retrieval model is constructed, which has certain theoretical basis, strong applicability and higher accuracy than before. Based on the Kubelka-Munk (KM) theory, the SOM retrieval model with the absorption coefficient k and scattering coefficient s related to SOM (r = k/s) is derived. The validity and reliability of the model are confirmed with validation set (n = 26) including three sorts of soils. Results show that the model can estimate SOM content in different sorts of soils with high prediction accuracy and good prediction ability (root mean square errors of prediction (RMSEP), coefficients of determination (R2) and relative percentage deviation (RPD) values of 0.18%, 89.9% and 3.2, respectively) in the range of 552-950nm. The model provides an innovative method for predicting SOM content.

The objective of the present study was to assess if trypsin, a key enzyme involved in protein digestion, presents some kind of functional adaptations to seasonal changes in water temperature in freshwater fish. In order to test this hypothesis, individuals of two fish species Carassius gibelio (agastric) and Perca fluviatilis (gastric) were sampled in the basin of Chany Lake (Siberia, Russia) at two different seasons (spring and summer). Apparent kinetic parameters (Km and Vmax) were determined for both species and seasons at the actual pH values in fish guts, and at actual temperatures. Results showed a significant effect of both the species and sampling season on the apparent kinetic parameters of trypsin. In the case of Prussian carp, Km and Vmax were lower for each assayed temperature (for 5 and 15 °C the differences were significant) for fish sampled in summer when compared to those sampled in spring. In contrast, values of Km in perch tended to be lower in spring at 5 and 25 °C but these differences were not significant, while Vmax showed a significant decrease in summer samples. This suggests a sort of functional adaptation of the same trypsin enzymes to seasonal changes, oriented to maximize protein digestion under variable conditions. [ABSTRACT FROM AUTHOR]

Few proteins have been characterized as abscisic acid transporters. Several of them are NRT1/PRT Family (NPF) transporters which have been characterized in yeast using reporter systems. Because several members of the NPF4 subfamily members were identified in yeast as ABA transporters, here, we screened for ABA transport activity the seven members of the NPF4 subfamily in Xenopus oocytes using cRNA injection and 3H-ABA accumulation. The ABA transport capacities of NPF4.2, NPF4.5, NPF4.6, and NPF4.7 were confirmed. The transport properties of NPF4.5 and NPF4.6 were studied in more detail. Both ABA transporter activities are pH-dependent and slightly pH-dependent apparent Km around 500 μM. There is no competitive inhibition of the ABA-analogs pyrabactin and quinabactin on ABA accumulation demonstrating a different selectivity compared to the ABA receptors. Functional expression of these ABA transporters in Xenopus oocyte is an opportunity to start structure–function studies and also to identify partner proteins of these hormone transporters.

Maximal velocity (Vmax) is a well established biomarker for the assessment of tissue redox status. There is scarce evidence, though, that it does not probably reflect sufficiently in vivo tissue redox profile. Instead, the Michaelis constant (Km) could more adequately image tissue oxidative stress and, thus, be a more physiologically relevant redox biomarker. Therefore, the aim of the present study was to side-by-side compare Vmax and Km of an antioxidant enzyme after implementing an in vivo set up that induces alterations in tissue redox status. Forty rats were divided into two groups including rats injected with blood plasma originating from rats that had previously swam until exhaustion and rats injected with blood plasma originating from sedentary rats. Tail-vein injections were performed daily for 21 days. Catalase Vmax and Km measured in gastrocnemius muscle were increased after administration of the exercise-conditioned plasma, denoting enhancement of the enzyme activity but impairment of its affinity for the substrate, respectively. These alterations are potential adaptations stimulated by the administered plasma pointing out that blood is an active fluid capable of regulating tissue homeostasis. Our findings suggest that Km adequately reflects in vivo modifications of skeletal muscle catalase and seems to surpass Vmax regarding its physiological relevance and biological interpretation. In conclusion, Km can be regarded as an in vivo-like biomarker that satisfactorily images the intracellular environment, as compared to Vmax that could be aptly parallelized with a biomarker that describes tissue oxidative stress in an in vitro manner.

Background: Software testing benefits from the usage of Knowledge Management (KM) methods and principles. Thus, there is a need to adopt KM to the software testing core processes and attain the benefits that it provides in terms of cost, quality, etc. Aim: To investigate the usage and implementation of KM for software testing. The major objectives include 1. To identify various software testing aspects that receive more attention while applying KM. 2. To analyse multiple software testing techniques, i.e. test design, test execution and test result analysis and highlight KM involvement in these. 3. To gather challenges faced by industry due to the lack of KM initiatives in software testing. Method: A Systematic Literature Review (SLR) was conducted utilizing the guidelines for snowballing reviews by Wohlin. The identified studies were analysed in relation to their rigor and relevance to assess the quality of the results. Results: The initial resulting set provided 4832 studies. From these, 35 peer-reviewed papers were chosen among which 31 are primary, and 4 are secondary studies. The literature review results indicated nine testing aspects being in focus when applying KM within various adaptation contexts and some benefits from KM application. Several challenges were identified, e.g., improper selection and application of better-suited techniques, a low reuse rate of software testing knowledge, barriers in software testing knowledge transfer, no possibility to quickly achieve the most optimum distribution of human resources during testing, etc. Conclusions: The study brings supporting evidence that the application of KM in software testing is necessary, e.g., to increase test effectiveness, select and apply testing techniques. The study outlines the testing aspects and testing techniques that benefit their users.