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ConspectusOver the past five decades, significant progress has been made in the field of anion recognition with a diverse variety of synthetic receptors because of the fundamental importance of anions in chemical, environmental, and biological processes. In particular, urea- and thiourea-based molecules offering directional binding sites are attractive receptors for anions due to their ability to bind anions employing primarily hydrogen-bonding interactions under neutral conditions and have gained a recent paramount attention in the area of supramolecular chemistry. The presence of two imine (-NH) groups on each urea/thiourea functionality in these receptors gives them potential for excellent binding of an anion, mimicking the natural binding process in living cells. The increased acidity offered by thiocarbonyl groups (CâS) in a thiourea-functionalized receptor could enhance its anion binding ability as compared to its analogous urea-based receptor containing a carbonyl (CâO) group. During the last several years, our group has been involved in exploring a wide variety of synthetic receptors, and we have studied them with anions experimentally and computationally. In this Account, we will highlight the overall summary of our group's efforts focusing on anion coordination chemistry of urea- and thiourea-based receptors with varying linkers (rigid and flexible), dimensions (dipodal and tripodal), and functionalities (bifunctional, trifunctional, and hexafunctional). Depending on the linkers and attached groups, bifunctional-based dipodal receptors can bind anions forming 1:1 or 1:2 complexes. A dipodal receptor with flexible aliphatic or rigid m-xylyl linkers forms a cleft to bind a single anionic species in the pocket. However, a dipodal receptor with p-xylyl linkers binds anions in both 1:1 and 1:2 binding modes. As compared to a dipodal receptor, a tripodal receptor provides a more organized cavity for an anion, forming predominantly a 1:1 complex, while the binding strength and selectivity are influenced by linking chains and terminal groups. A hexafunctional-based tripodal receptor bridged with o-phenylene groups provides two clefts that can host two small anions or one large anion. However, a hexafunctional receptor with p-phenylene groups as linkers binds two anions, one at an inner pocket and the other at an outer pocket. It was shown that the presence of suitable chromophores at the terminal groups makes the receptor useful for the naked-eye detection for certain anions (e.g., fluoride, acetate) in solution. The field of anion binding chemistry is rapidly growing, and this Account aims to provide fundamental aspects influencing the binding strength and selectivity of anionic species with abiotic receptors which might eventually be useful for the development of new devices for binding, sensing, and separating biologically and environmentally important anions.
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BACKGROUND: Worldwide, a significant number of girls become mothers during adolescence. In Bangladesh, adolescent childbirth is highly prevalent and has adverse effects on children's health and undernutrition. We aimed to identify the relationship between the undernutrition of children and adolescent motherhood, the factors associated with adolescent mothers' age at first birth, and to examine the programmatic factors and gaps influencing children's undernutrition in Bangladesh. METHODS: We analysed the 'Bangladesh Demographic and Health Survey' BDHS-17-18 data and desk review. To examine the factors associated with adolescent motherhood and its impact on child undernutrition, data from 7,643 mother-child pairs were selected. Child stunting, wasting, and underweight were measured according to the World Health Organisation (WHO) median growth guidelines based on z-scores - 2. Univariate, bivariate, simple, and multiple logistic regressions were used for analyse. We followed the systematic procedures for the literature review. RESULTS: Approximately, 89% of adolescents aged ≤ 19 years were married and 71% of them gave their first childbirth. Children of adolescent mothers (≤ 19 years) were significantly 1.68 times more wasted (aOR: 1.68; 95% CI: 1.08 to 2.64), 1.37 times more underweight (aOR: 1.37; 95% CI: 1.01 to 1.86) and either form 1.32 times more stunting, wasting or underweight (aOR:1.32; 95% Cl: 1.05 to 1.66) compared to the children of adult mothers (> 19 years) after adjusting potential confounders. The factors associated with mothers' first childbirth during adolescence were the age gap between husband and wife 5-10 years (aOR: 1.81; 95% Cl: 1.57-2.10) and age gap > 10 years (aOR: 2.41; 95% Cl: 1.96-2.97) compared with the age group < 5 years, and husbands' education (aOR: 1.29; 95% Cl: 1.04-1.61) compared with the uneducated husbands. In the literature review, we found potential gaps in focusing on the Adolescent Sexual and Reproductive Health (ASRH) program in Bangladesh, from thirty-two programmes only half of them focused on adolescents aged 10-19 years, and eleven programmes focused only on girls. CONCLUSION: Children of adolescent mothers are at risk of wasting, underweight, and any form of undernutrition. For effective policies and interventions in Bangladesh, it is important to emphasise delaying adolescent pregnancy and prioritising child undernutrition.
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Gravidez na Adolescência , Humanos , Adolescente , Bangladesh/epidemiologia , Feminino , Gravidez na Adolescência/estatística & dados numéricos , Adulto Jovem , Transtornos da Nutrição Infantil/epidemiologia , Gravidez , Criança , Pré-Escolar , Lactente , Fatores Socioeconômicos , Adulto , Inquéritos Epidemiológicos , Fatores Sociodemográficos , Mães/estatística & dados numéricos , Mães/psicologia , Magreza/epidemiologia , MasculinoRESUMO
Vehicular edge computing (VEC) is one of the prominent ideas to enhance the computation and storage capabilities of vehicular networks (VNs) through task offloading. In VEC, the resource-constrained vehicles offload their computing tasks to the local road-side units (RSUs) for rapid computation. However, due to the high mobility of vehicles and the overloaded problem, VEC experiences a great deal of challenges when determining a location for processing the offloaded task in real time. As a result, this degrades the quality of vehicular performance. Therefore, to deal with these above-mentioned challenges, an efficient dynamic task offloading approach based on a non-cooperative game (NGTO) is proposed in this study. In the NGTO approach, each vehicle can make its own strategy on whether a task is offloaded to a multi-access edge computing (MEC) server or a cloud server to maximize its benefits. Our proposed strategy can dynamically adjust the task-offloading probability to acquire the maximum utility for each vehicle. However, we used a best response offloading strategy algorithm for the task-offloading game in order to achieve a unique and stable equilibrium. Numerous simulation experiments affirm that our proposed scheme fulfills the performance guarantees and can reduce the response time and task-failure rate by almost 47.6% and 54.6%, respectively, when compared with the local RSU computing (LRC) scheme. Moreover, the reduced rates are approximately 32.6% and 39.7%, respectively, when compared with a random offloading scheme, and approximately 26.5% and 28.4%, respectively, when compared with a collaborative offloading scheme.
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BACKGROUND: Post-hospital discharge mortality risk is high among young children in many low and middle-income countries (LMICs). The available literature suggests that child, caregiver and health care provider gender all play important roles in post-discharge adherence to medical advice, treatment-seeking and recovery for ill children in LMICs, including those with undernutrition. METHODS: A qualitative study was embedded within a larger multi-country multi-disciplinary observational cohort study involving children aged less than 2 years conducted by the Childhood Acute Illness and Nutrition (CHAIN) Network. Primary data were collected from family members of 22 purposively selected cohort children. Family members were interviewed several times in their homes over the 6 months following hospital discharge (total n = 78 visits to homes). These in-depth interviews were complemented by semi-structured individual interviews with 6 community representatives, 11 community health workers and 12 facility-based health workers, and three group discussions with a total of 24 community representatives. Data were analysed using NVivo11 software, using both narrative and thematic approaches. RESULTS: We identified gender-related influences at health service/system and household/community levels. These influences interplayed to family members' adherence to medical advice and treatment-seeking after hospital discharge, with potentially important implications for children's recovery. Health service/system level influences included: fewer female medical practitioners in healthcare facilities, which influenced mothers' interest and ability to consult them promptly for their child's illnesses; gender-related challenges for community health workers in supporting mothers with counselling and advice; and male caregivers' being largely absent from the paediatric wards where information sessions to support post-discharge care are offered. Gendered household/community level influences included: women's role as primary caretakers for children and available levels of support; male family members having a dominant role in decision-making related to food and treatment-seeking behaviour; and greater reluctance among parents to invest money and time in the treatment of female children, as compared to male children. CONCLUSIONS: A complex web of gender related influences at health systems/services and household/community levels have important implications for young children's recovery post-discharge. Immediate interventions with potential for positive impact include awareness-raising among all stakeholders - including male family members - on how gender influences child health and recovery, and how to reduce adverse consequences of gender-based discrimination. Specific interventions could include communication interventions in facilities and homes, and changes in routine practices such as who is present in facility interactions. To maximise and sustain the impact of immediate actions and interventions, the structural drivers of women's position in society and gender inequity must also be tackled. This requires interventions to ensure equal equitable opportunities for men and women in all aspects of life, including access to education and income generation activities. Given patriarchal norms locally and globally, men will likely need special targeting and support in achieving these objectives.
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Assistência ao Convalescente , Mães/psicologia , Poder Psicológico , Cooperação e Adesão ao Tratamento , Idoso , Bangladesh , Criança , Pré-Escolar , Feminino , Hospitais , Humanos , Lactente , Entrevistas como Assunto , Masculino , Alta do Paciente , Gravidez , Pesquisa Qualitativa , Cooperação e Adesão ao Tratamento/etnologia , Cooperação e Adesão ao Tratamento/psicologiaRESUMO
BACKGROUND: Undernourished children in low- and middle-income countries remain at elevated risk of death following hospital discharge, even when treated during hospitalisation using World Health Organisation recommended guidelines. The role of community health workers (CHWs) in supporting post-discharge recovery to improve outcomes has not been adequately explored. METHODS: This paper draws on qualitative research conducted as part of the Childhood Acute Illnesses and Nutrition (CHAIN) Network in Bangladesh and Kenya. We interviewed family members of 64 acutely ill children admitted across four hospitals (a rural and urban hospital in each country). 27 children had severe wasting or kwashiorkor on admission. Family members were interviewed in their homes soon after discharge, and up to three further times over the following six to fourteen months. These data were supplemented by observations in facilities and homes, key informant interviews with CHWs and policy makers, and a review of relevant guidelines. RESULTS: Guidelines suggest that CHWs could play a role in supporting recovery of undernourished children post-discharge, but the mechanisms to link CHWs into post-discharge support processes are not specified. Few families we interviewed reported any interactions with CHWs post-discharge, especially in Kenya, despite our data suggesting that opportunities for CHWs to assist families post-discharge include providing context sensitive information and education, identification of danger signs, and supporting linkages with community-based services and interventions. Although CHWs are generally present in communities, challenges they face in conducting their roles include unmanageable workloads, few incentives, lack of equipment and supplies and inadequate support from supervisors and some community members. CONCLUSION: A multi-pronged approach before or on discharge is needed to strengthen linkages between CHWs and children vulnerable to poor outcomes, supported by clear guidance. To encourage scale-ability and cost-effectiveness of interventions, the most vulnerable, high-risk children, should be targeted, including undernourished children. Intervention designs must also take into account existing health worker shortages and training levels, including for CHWs, and how any new tasks or personnel are incorporated into hospital and broader health system hierarchies and systems. Any such interventions will need to be evaluated in carefully designed studies, including tracking for unintended consequences.
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Agentes Comunitários de Saúde , Alta do Paciente , Assistência ao Convalescente , Bangladesh , Criança , Hospitais , Humanos , Quênia , Pesquisa QualitativaRESUMO
Multi-access edge computing (MEC) is a new leading technology for meeting the demands of key performance indicators (KPIs) in 5G networks. However, in a rapidly changing dynamic environment, it is hard to find the optimal target server for processing offloaded tasks because we do not know the end users' demands in advance. Therefore, quality of service (QoS) deteriorates because of increasing task failures and long execution latency from congestion. To reduce latency and avoid task failures from resource-constrained edge servers, vertical offloading between mobile devices with local-edge collaboration or with local edge-remote cloud collaboration have been proposed in previous studies. However, they ignored the nearby edge server in the same tier that has excess computing resources. Therefore, this paper introduces a fuzzy decision-based cloud-MEC collaborative task offloading management system called FTOM, which takes advantage of powerful remote cloud-computing capabilities and utilizes neighboring edge servers. The main objective of the FTOM scheme is to select the optimal target node for task offloading based on server capacity, latency sensitivity, and the network's condition. Our proposed scheme can make dynamic decisions where local or nearby MEC servers are preferred for offloading delay-sensitive tasks, and delay-tolerant high resource-demand tasks are offloaded to a remote cloud server. Simulation results affirm that our proposed FTOM scheme significantly improves the rate of successfully executing offloaded tasks by approximately 68.5%, and reduces task completion time by 66.6%, when compared with a local edge offloading (LEO) scheme. The improved and reduced rates are 32.4% and 61.5%, respectively, when compared with a two-tier edge orchestration-based offloading (TTEO) scheme. They are 8.9% and 47.9%, respectively, when compared with a fuzzy orchestration-based load balancing (FOLB) scheme, approximately 3.2% and 49.8%, respectively, when compared with a fuzzy workload orchestration-based task offloading (WOTO) scheme, and approximately 38.6%% and 55%, respectively, when compared with a fuzzy edge-orchestration based collaborative task offloading (FCTO) scheme.
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Dual-acting virucidal entry inhibitors (DAVEIs) have previously been shown to cause irreversible inactivation of HIV-1 Env-presenting pseudovirus by lytic membrane transformation. This study examined whether this transformation could be generalized to include membranes of Env-presenting cells. Flow cytometry was used to analyze HEK293T cells transiently transfected with increasing amounts of DNA encoding JRFL Env, loaded with calcein dye, and treated with serial dilutions of microvirin (Q831K/M83R)-DAVEI. Comparing calcein retention against intact Env expression (via Ab 35O22) on individual cells revealed effects proportional to Env expression. "Low-Env" cells experienced transient poration and calcein leakage, while "high-Env" cells were killed. The cell-killing effect was confirmed with an independent mitochondrial activity-based cell viability assay, showing dose-dependent cytotoxicity in response to DAVEI treatment. Transfection with increasing quantities of Env DNA showed further shifts toward "High-Env" expression and cytotoxicity, further reinforcing the Env dependence of the observed effect. Controls with unlinked DAVEI components showed no effect on calcein leakage or cell viability, confirming a requirement for covalently linked DAVEI compounds to achieve Env transformation. These data demonstrate that the metastability of Env is an intrinsic property of the transmembrane protein complex and can be perturbed to cause membrane disruption in both virus and cell contexts.
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Proteínas de Bactérias/farmacologia , Membrana Celular/metabolismo , Membrana Celular/virologia , Inibidores da Fusão de HIV/farmacologia , Lectina de Ligação a Manose/farmacologia , Internalização do Vírus/efeitos dos fármacos , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Sequência de Aminoácidos , Membrana Celular/efeitos dos fármacos , Células HEK293 , Humanos , Estabilidade Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Produtos do Gene env do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Produtos do Gene env do Vírus da Imunodeficiência Humana/químicaRESUMO
Two thiophene-based monocyclic receptors L1 and L2 have been studied for phosphate binding in solutions (D2O and DMSO-d6 ) by 1H NMR and 31P NMR titrations, and in the solid state by single crystal X-ray analysis. Results from 1H NMR titrations suggest that the ligands bind phosphate anions in a 1:2 binding mode in DMSO-d6 , with the binding constants of 5.25 and 4.20 (in log K), respectively. The binding of phosphate to L1 and L2 was further supported by 31P NMR in D2O at pH = 5.2. The crystal structure of the phosphate complex of L1 reveals unambiguous proof for the formation of a ditopic complex via multiple hydrogen bonds from NH···O and CH···O interactions.
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A p-xylyl-based macrocycle L has been synthesized and its binding properties with halides have been investigated by (1)H NMR titrations, single crystal X-ray diffraction analysis, and density functional theory (DFT) calculations. As investigated by (1)H NMR titrations, the ligand preferentially binds a halide in a 1:2 binding mode, with the association constants (in log K2) of 2.82, 2.70, 2.28, and 2.20 for fluoride, chloride, bromide, and iodide, respectively. The overall binding trend was found to be in the order of fluoride > chloride > bromide > iodide, reflecting that the binding strength correlates with the relative basicity and size of the respective halide. Crystallographic studies indicate that the ligand forms 1:2 complexes with chloride, bromide and iodide. In the chloride complex, the ligand is hexaprotonated and each chloride is held via three NH···Cl(-) bonds. The ligand is tetraprotonated for the other complexes, where each halide is H-bonded to two secondary ammonium NH(+) groups via NH···X(-) bonds. The results of DFT calculations performed on [H6L](6+) at M062x/6-311G (d,p) level in both gas and solvent phases, suggest that the ligand binds halides with the binding energy in the order of F(-) > Cl(-) > Br(-) > I(-), supporting the experimental data obtained from (1)H NMR studies. Results from DFT calculations further indicate that a 1:2 binding is energetically more favorable than a 1:1 binding of the ligand.
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Compostos Aza/química , Brometos/química , Cloretos/química , Fluoretos/química , Iodetos/química , Compostos Macrocíclicos/química , Compostos Aza/síntese química , Cristalografia por Raios X , Gases/química , Ligação de Hidrogênio , Ligantes , Compostos Macrocíclicos/síntese química , Modelos Químicos , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Prótons , Solventes/química , TermodinâmicaRESUMO
Treatment of diseases with synthetic materials has been an aspiration of mankind since the dawn of human development. In this research, three complex compounds of azamacrocycle (TD1, TD2, and TD3) were synthesized, and experiments were conducted to determine whether their toxicity to human liver carcinoma (HepG2 ) cells is associated with apoptotic and/or necrotic cell death. Cell survival was determined by MTT assay. Apoptosis and necrosis were measured by annexin V FITC/PI assay using the flow cytometry and by propidium iodide (PI) assay using the cellometer vision. HepG2 cells were treated with different concentrations of azamacrocycles for 48 h. Results from MTT assay indicated that all the three azamacrocycles significantly (p < 0.05) reduce cell viability in a dose-dependent manner, showing 48 h-LD50 values of about 37.97, 33.60, and 19.29 µM, for TD3, TD1 and TD2, respectively. Among the three compounds tested, TD2 showed the most pronounced cytotoxic activity against HepG2 cells, being about twofold more potent than TD3. The order of toxicity was TD2 > TD1 > TD3. Because TD2 exerted the most cytotoxic activity against HepG2 cells, it was used in the subsequent apoptosis and necrosis-related experiments. The flow cytometry assessment showed a strong dose-response relationship with regard to TD2 exposure and annexin V/PI positive cells. PI assay data indicated that TD2 exposure increased the proportion of fluorescence positive cells. Overall, our results indicate that azamacrocycle toxicity to HepG2 cells is associated with apoptotic and necrotic cell death resulting from phosphatidylserine externalization and loss of membrane integrity.
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Apoptose , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Compostos Macrocíclicos/farmacologia , Necrose , Antineoplásicos/farmacologia , Sobrevivência Celular , Citometria de Fluxo , Células Hep G2 , HumanosRESUMO
Social media has become integral to contemporary society, with online behaviors impacting individual experiences and the wider community. In Bangladesh, a developing country, SNS have played a pivotal role in the nation's digitalization efforts. This study explores the relationship between social capital theory, D&M Information System Model, subjective well-being, and SNS Citizenship Behavior (SCB) among active social media users in Bangladesh. Data was collected from 418 participants through an online survey, and hypotheses were tested using structural equation modeling. The findings indicate that the items of the D&M model positively influenced the aspects of social capital theory, excluding service quality. In contrast, social interaction ties and shared values were positively associated with SCB, although social trust did not exhibit a significant relationship. Additionally, subjective well-being mediated the connection between social capital and SCB. This research offers valuable insights into the factors influencing online prosocial behavior and provides practical implications for cultivating a positive communication culture in the digital era. The model proposed in this study holds significant implications for Bangladesh's policymakers and social networking site authorities, guiding their efforts in implementing technology-based initiatives.
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The extent of drought tolerance in the seedlings of three wheat cultivars (WMRI-1, BARI GOM-33 and BARI GOM-21) was investigated by seed and root priming using abscisic acid (ABA) and glycine betaine (GB). The seeds were primed with ABA (10 and 20 µM) and GB (50 and 100 mM) and grown in pots maintaining control (0 % PEG) and drought (10 % PEG) conditions. Under drought, the root and shoot length, root and shoot biomass were significantly increased in ABA and GB primed seedlings than non-primed seedlings in all cultivars. Among the priming agents, either 20 µM ABA or 50 mM GB triggered better seedling growth in all wheat cultivars. These two levels were then applied with the nutrient solution in the hydroponics following four treatments: Control, Drought, Drought + ABA and Drought + GB. The seedling growth significantly declined in drought, while an improved seedling growth was observed in ABA and GB-treated plants in all cultivars. A considerable increase in lipid peroxidation, proline content, total antioxidant capacity and total flavonoid content in roots and leaves were recorded in all drought conditions, while these values were considerably reduced in ABA and GB treatments. Hierarchical clustering heatmap using stress tolerance index (STI) values showed that Drought + ABA and Drought + GB secured higher STI scores suggesting a greater degree of drought tolerance in all cultivars. In conclusion, seed and root priming of ABA and GB enhanced drought tolerance in the wheat seedlings by improving seedling growth and antioxidative defense suggesting a declined state of oxidative damage.
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BACKGROUND: Problematic smartphone use (PSU) and attention deficit hyperactivity disorder (ADHD) in children, adolescents, and young adults are of major concern to parents. However, the prevalence and associated factors related to these issues in Bangladeshi adolescents and young adults remain unclear to the best of our knowledge. The aim of this study is to assess PSU and ADHD in the context of adolescent and young adult age groups in Bangladesh. METHODS: The present study collected data from diverse geographical locations in Bangladesh via face-to-face surveys using stratified random sampling methods. We considered age, sex, and geographic location stratification criteria. A total of 578 respondents participated in the survey initially. From this, we discarded 36 responses after screening because the information provided was insufficient or incomplete response. In the end, 542 replies were incorporated into the final analysis. PSU and ADHD depend on several factors, including the individual's demographic background. RESULTS: The prevalence of PSU and ADHD symptoms in adolescents and young adults in Bangladesh is 61.44% and 37.45%, respectively based on our findings. The symptoms of PSU are correlated with age, education level, family type (nuclear/joint), sleeping pattern, physical exercise, and residence area. ADHD symptoms are correlated with age, education level, living with family, smoking habit, physical disability, sleeping pattern, physical exercise, residence area, and PSU. Also, we observed that ADHD and PSU symptoms are positively correlated with each other. CONCLUSION: A large proportion of young adults and adolescents reported PSU and ADHD symptoms. The present findings have practical implications in clinical psychology, psychotherapy, and related policy considerations. We propose to develop an inclusive interventional strategy and community-based programs to address PSU and ADHD-related issues.
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Transtorno do Deficit de Atenção com Hiperatividade , Smartphone , Humanos , Adolescente , Bangladesh/epidemiologia , Feminino , Masculino , Adulto Jovem , Estudos Transversais , Prevalência , Smartphone/estatística & dados numéricos , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Adulto , Inquéritos e Questionários , Transtorno de Adição à Internet/epidemiologiaRESUMO
In the centrosymmetric trinuclear Zn(II)â¯Ca(II)â¯Zn(II) title complex, [CaZn2(CH3COO)6(C12H12N2)2], the Ca(II) ion lies on an inversion centre and is octa-hedrally coordinated by six acetate O atoms. The Zn(II) ion is coordinated by two N atoms from a bidentate di-methyl-bipyridine ligand and three O atoms from acetate ligands bridging to the Ca(II) ion, leading to a distorted square-pyramidal coordination sphere. The Znâ¯Ca distance is 3.4668â (5)â Å.
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In the title compound, C24H40N4S3 (4+)·2SiF6 (2-)·3CH3OH, the central tertiary amine function is protonated and is connected to three thio-phen-2-yl-methyl-amino-n-propyl groups, forming the arms of a T-shaped cation that has two pockets. Each arm contains one protonated secondary amine function, and each pocket is occupied by one SiF6 (2-) anion bonded via two N-Hâ¯F inter-actions with the protonated amine group on the middle arm, while two methanol solvent mol-ecules are N-Hâ¯O hydrogen-bonded with the other secondary protonated amine groups on the side arms. Weak O-Hâ¯O and O-Hâ¯F hydrogen bonds between the solvent mol-ecules and between the solvent mol-ecules and the anions, respectively, are also observed. All three thio-phene groups in the arms are disordered over two sets of sites, with occupancy ratios of 0.828â (3):0.172â (3), 0.910â (2):0.090â (2) and 0.890â (3):0.110â (3).
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The title compound, [Ag(C9H13N5S)Cl(C18H15P)2], crystallizes with four independent mol-ecules in the asymmetric unit, in each of which the Ag atom is in a distorted tetra-hedral coordination, defined by the chloride ligand, the S atom of the neutral ligand and two P atoms derived from the triphenyl phosphine ligands. The thio-semicarbazone acts as a monodentate ligand through its thione S atom. An intra-molecular N-Hâ¯Cl hydrogen bond occurs in two of the independent mol-ecules. In the crystal, the mol-ecules are assembled through N-Hâ¯Cl hydrogen bonds, forming chains along [101].
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In the title complex, [Cd(C12H11N4S2)I(C12H12N4S2)], the Cd(II) ion is penta-coordinated by two thio-semicarbazone ligands (one neutral and the other anionic) and one iodide ion in a distorted square pyramidal (τ = 0.35) geometry. The central ion is coordinated by the thia-zole N atom, the thio-ureido N and the S atom of the deprotonated thio-semicarbazone ligand. The other ligand is linked with the central ion through the C=S group. The deprotonated ligand intra-molecularly hydrogen bonds to the thia-zole ring N atom, while the ligand forms an inter-molecular hydrogen bond to the thiol-ate S atom of the second ligand. The deprotonation of the tridentate ligand and its coordination to the Cd(II) ion via the S atom strikingly affects the C-S bond lengths. The C-S bond lengths in the neutral and deprotonated ligands in the metal complex are 1.709â (3) and 1.748â (2)â Å, respectively, whereas it is 1.671â (3)â Å in the free ligand. In the metal complex, the Cd-S distances are 2.6449â (6) and 2.5510â (6)â Å. The Cd-I bond length is 2.7860â (2)â Å.
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In the age of sophisticated cyber threats, botnet detection remains a crucial yet complex security challenge. Existing detection systems are continually outmaneuvered by the relentless advancement of botnet strategies, necessitating a more dynamic and proactive approach. Our research introduces a ground-breaking solution to the persistent botnet problem through a strategic amalgamation of Hybrid Feature Selection methods-Categorical Analysis, Mutual Information, and Principal Component Analysis-and a robust ensemble of machine learning techniques. We uniquely combine these feature selection tools to refine the input space, enhancing the detection capabilities of the ensemble learners. Extra Trees, as the ensemble technique of choice, exhibits exemplary performance, culminating in a near-perfect 99.99% accuracy rate in botnet classification across varied datasets. Our model not only surpasses previous benchmarks but also demonstrates exceptional adaptability to new botnet phenomena, ensuring persistent accuracy in a landscape of evolving threats. Detailed comparative analyses manifest our model's superiority, consistently achieving over 99% True Positive Rates and an unprecedented False Positive Rate close to 0.00%, thereby setting a new precedent for reliability in botnet detection. This research signifies a transformative step in cybersecurity, offering unprecedented precision and resilience against botnet infiltrations, and providing an indispensable blueprint for the development of next-generation security frameworks.
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The purpose of this paper is to explore the relationship between corporate social responsibility (CSR) and firm value in the Chinese market and identify factors that may influence it. We discuss the relationship between CSR engagement in Chinese firms and firm value from a nonlinear perspective. In addition, we examine how the degree of internationalization in a firm may affect the relationship between CSR and firm value. We employ the Hausman test to compare a random-effects and a fixed-effects model, and after testing and comparison, the fixed-effects model was chosen in our paper. Using data from 314 firms listed in China's A-shares market from 2010 to 2017, we verify the U-shaped relationship between CSR and firm value. Meanwhile, the degree of internationalization will affect firm value but cannot positively regulate the relationship between corporate social responsibility and firm value.
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Indústrias , Responsabilidade Social , China , Indústrias/éticaRESUMO
BACKGROUND: The human immunodeficiency virus (HIV) burden has frequently been changing over time due to epidemiological and demographic transitions. To safeguard people, particularly women of reproductive age, who can be exposed to transmitting this burden to the next generation, knowledge regarding this life-threatening virus needs to be increased. This research intends to identify the trends and associated correlates of "low" HIV knowledge among ever-married women of reproductive age in Bangladesh from 1996 to 2014. METHODS: We analyzed data derived from six surveys of Bangladesh Demographic and Health Surveys conducted in 1996, 1999, 2004, 2007, 2011, and 2014. Analyses were primarily restricted to ever-married women aged 15-49 years who had ever heard of HIV. The correlates of "low" HIV knowledge were investigated using multiple binary logistic regression models. RESULTS: The study found that the proportion of women with "low" HIV knowledge decreased from 72% in 1996 to 58% in 2014. In adjusted models, age at first marriage, level of education, wealth quintile, and place of residence (except in the survey year 2011) were found to be potential correlates of "low" HIV knowledge in all survey years. In the pooled analysis, we found lower odds of "low" HIV knowledge in the survey years 1999 (Adjusted Odds Ratio: 0.67; 95% CI: 0.57, 0.78), 2004 (AOR: 0.60; 95% CI: 0.52, 0.70), 2007 (AOR: 0.51; 95% CI: 0.44, 0.60), 2011 (AOR: 0.36; 95% CI: 0.32, 0.42) and 2014 (AOR: 0.47; 95% CI: 0.41, 0.54) compared to the survey year 1996. CONCLUSION: The proportion of "low" HIV knowledge has declined over time, although the proportion of women with "low" HIV knowledge still remains high. The prevention of early marriage, the inclusion of HIV-related topics in the curricula, reduction of disparities between urban-rural and the poorest-richest groups may help to improve the level of HIV knowledge among ever-married Bangladeshi women.