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1.
J Comput Chem ; 45(29): 2476-2500, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970309

RESUMO

This paper is the first to look at the structural, electronic, mechanical, optical, and thermodynamic properties of the ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) half-Heusler (HH) using DFT based first principles method. The lattice parameters that we have calculated are very similar to those obtained in prior investigations with theoretical and experimental data. The positive phonon dispersion curve confirm the dynamical stability of ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn). The electronic band structure and DOS confirmed that the studied materials ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) are direct band gap semiconductors. The investigation also determined significant constants, including dielectric function, absorption, conductivity, reflectivity, refractive index, and loss function. These optical observations unveiled our compounds potential utilization in various electronic and optoelectronic device applications. The elastic constants were used to fulfill the Born criteria, confirming the mechanical stability and ductility of the solids ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn). The calculated elastic modulus revealed that our studied compounds are elastically anisotropic. Moreover, ANiX (ASc, Ti, Y, Zr, Hf; XBi, Sn) has a very low minimum thermal conductivity (Kmin), and a low Debye temperature (θD), which indicating their appropriateness for utilization in thermal barrier coating (TBC) applications. The Helmholtz free energy (F), internal energy (E), entropy (S), and specific heat capacity (Cv) are determined by calculations derived from the phonon density of states.

2.
Environ Monit Assess ; 193(4): 218, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33758982

RESUMO

Drought is an affliction for a region that primarily depends on agriculture as economic activity. Commonly monitoring and characterizing of drought is performed by only analyzing the meteorological aspect, assuming precipitation as the primary source of water. However, in riverine Bangladesh, this can lead to an erroneous conclusion, as there is a multitude of available water sources. Consequently, in this study, vegetation condition (Standard Vegetation Index), soil moisture (Soil Moisture Index), and precipitation (Standard Precipitation Index) are separately investigated from 2003 to 2019, in the Northwestern Teesta floodplain. Subsequently, statistical regression analysis is performed to determine the relationships between different aspects of drought. In addition, information obtained from field visits and expert opinions has also been assimilated. Analysis of vegetation and soil moisture condition presents a progressively improving scenario. However, SPI shows an incessant decline in meteorological drought conditions, especially after 2007. Evidently, regression analysis does not provide any indication of an interrelationship between the studied agricultural and meteorological parameters. Presumably, this absence is instigated because the study area is highly irrigated as the groundwater table is suitably near the surface and the existence of nearby Teesta river allows for the utilization of surface water. Moreover, the cropping pattern is shifting toward crops that require much less water and to places where soil moisture is scarce. Thus, this study addresses the gap in knowledge regarding the nature of agricultural drought and the dynamics of different aspects of drought which will be invaluable for the water management and agricultural policy in the study area as well as other regions with a similar backdrop.


Assuntos
Secas , Tecnologia de Sensoriamento Remoto , Agricultura , Bangladesh , Monitoramento Ambiental
3.
Water Sci Technol ; 77(5-6): 1418-1430, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29528329

RESUMO

This study was conducted to assess the levels of toxic metals like arsenic (As), chromium (Cr), cadmium (Cd), and lead (Pb) in water and sediments of the Pasur River in Bangladesh. The ranges of Cr, As, Cd, Pb in water were 25.76-77.39, 2.76-16.73, 0.42-2.98 and 12.69-42.67 µg/L and in sediments were 20.67-83.70, 3.15-19.97, 0.39-3.17 and 7.34-55.32 mg/kg. The level of studied metals in water samples exceeded the safe limits of drinking water, indicating that water from this river is not safe for drinking and cooking. Certain indices, including pollution load index (PLI) and contamination factor (Cif) were used to assess the ecological risk. The PLI indicated progressive deterioration of sediments by the studied metals. Potential ecological risks of metals in sediment indicated low to considerable risk. However, the Cif values of Cd ranged from 0.86 to 8.37 revealed that the examined sediments were strongly impacted by Cd. Considering the severity of potential ecological risk (PER) for single metal (Eir), the descending order of contaminants was Cd > Pb > As > Cr. According the results, some treatment scheme must formulate and implement by the researchers and related management organizations to save the Pasur River from metals contamination.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/química , Bangladesh , Poluição Ambiental , Metais Pesados/análise , Medição de Risco , Água
4.
Cardiovasc Toxicol ; 24(1): 27-40, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971645

RESUMO

Arsenic contamination is a global health concern, primarily through contaminated groundwater and its entry into the food chain. The association between arsenic exposure and cardiovascular diseases (CVDs) is particularly alarming due to CVDs being the leading cause of death worldwide. Arsenic exposure has also been linked to changes in telomere length, mitochondrial DNA copy number (mtDNAcn), and deletion, further increasing the risk of CVDs. We aimed to determine whether arsenic exposure alters telomere length and mtDNAcn and deletion in a total of 50 CVD patients who underwent open heart surgery hailed from known arsenic-affected and unaffected areas in Bangladesh. Amount of arsenic was determined from the collected nails and cardiac tissues. Relative telomere length and mtDNAcn and deletion were quantified by qRT-PCR. The patients from arsenic-contaminated areas had higher average arsenic deposits in their fingers and toenails (P < 0.05) and higher cardiac tissue injury scores (P < 0.05). Moreover, approximately 1.5-fold shorter telomere length (P < 0.05, r = - 0.775), 1.2-fold decreased mtDNAcn (P < 0.05, r = - 0.797), and an 81-fold higher amount of mitochondrial DNA deletion (P < 0.05, r = 0.784) were observed in the patients who had higher arsenic deposition in their nails. Higher levels of arsenic exposure were found to be linked to shorter telomere length, decreased mtDNAcn, and increased mitochondrial DNA deletion in the patients from As-affected areas. It can also be anticipated that the correlation of arsenic exposure with telomere length, mtDNAcn, and deletion can be used as biomarkers for early diagnosis of arsenic-induced cardiovascular diseases.


Assuntos
Arsênio , Doenças Cardiovasculares , Humanos , DNA Mitocondrial/genética , Arsênio/toxicidade , Variações do Número de Cópias de DNA , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Telômero/genética
5.
Vet Med Sci ; 10(6): e70100, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39470115

RESUMO

A 12 years-old, male indigenous dog was presented to Shahedul Alam Qaderi Teaching Veterinary Hospital (SAQTVH) in Chattogram, Bangladesh with a large tumour on its right front leg. The histopathological findings of the tumour were highly suggestive of an alveolar rhabdomyosarcoma (ARMS). The tumour was surgically removed from the dog. While there had been no recurrence for 5 months, the patient died 5 months post-operatively. The cause of the death and presence of metastasis could not be confirmed as follow-up investigations were declined by the owner. A histopathological study showed poorly differentiated neoplastic mononuclear cells forming nests in an alveolar pattern. Despite that the limited resources prevented myogenin staining for diagnostic confirmation, the well-contained, defined appearance of the tumour supports the diagnosis of ARMS. This report highlights the challenges in diagnosing and treating ARMS in indigenous dogs and emphasizes the need for further research and diagnostic markers to improve detection and management.


Assuntos
Doenças do Cão , Rabdomiossarcoma Alveolar , Cães , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/cirurgia , Doenças do Cão/patologia , Masculino , Rabdomiossarcoma Alveolar/veterinária , Rabdomiossarcoma Alveolar/patologia , Rabdomiossarcoma Alveolar/diagnóstico , Bangladesh , Evolução Fatal
6.
Environ Sci Pollut Res Int ; 31(2): 2343-2359, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38057678

RESUMO

Toxic metals and freshwater fish's metalloid contamination are significant environmental concerns for overall public health. However, the bioaccumulation and sources of metal(loids) in freshwater fishes from Bangladesh still remain unknown. Thus, the As, Pb, Cd, and Cr concentrations in various freshwater fish species from the Rupsha River basin were measured, including Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, and Pseudeutropius atherinoides. An atomic absorption spectrophotometer was used to determine metal concentrations. The mean concentrations of metal(loids) in the fish muscle (mg/kg) were found to be As (1.53) > Pb (1.25) > Cr (0.51) > Cd (0.39) in summer and As (1.72) > Pb (1.51) > Cr (0.65) > Cd (0.49) in winter. The analyzed fish species had considerably different metal(loid) concentrations with seasonal variation, and the distribution of the metals (loids) was consistent with the normal distribution. The demersal species, M. vittatus, displayed the highest bio-accumulative value over the summer. However, in both seasons, none of the species were bio-accumulative. According to multivariate statistical findings, the research area's potential sources of metal(loid) were anthropogenic activities linked to geogenic processes. Estimated daily intake, target hazard quotient (THQ), and carcinogenic risk (CR) were used to assess the influence of the risk on human health. The consumers' THQs values were < 1, indicating that there were no non-carcinogenic concerns for local consumers. Both categories of customers had CRs that fell below the permissible range of 1E - 6 to 1E - 4, meaning they were not at any increased risk of developing cancer. The children's group was more vulnerable to both carcinogenic and non-carcinogenic hazards. Therefore, the entry of metal(loids) must be regulated, and appropriate laws must be used by policymakers.


Assuntos
Peixes-Gato , Metais Pesados , Poluentes Químicos da Água , Animais , Criança , Humanos , Metais Pesados/análise , Rios , Cádmio , Bioacumulação , Saúde Pública , Bangladesh , Chumbo , Peixes , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Medição de Risco
7.
Food Chem Toxicol ; : 114580, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467293

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

8.
Polymers (Basel) ; 15(4)2023 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-36850325

RESUMO

This work investigates the effects of fibre content, fibre orientation, and frequency on the dynamic behaviour of flax fibre-reinforced polypropylene composites (FFPCs) to improve understanding of the parameters affecting vibration damping in FFPCs. The effects of fibre content and fibre orientation on the mechanical performances of FFPCs, along with fracture characteristics, are also investigated in this study. Laminates of various fibre contents and orientations were manufactured by a vacuum bagging process, and their dynamic and static properties were then obtained using dynamic (dynamic mechanical analysis (DMA) to frequencies of 100 Hz) and various mechanical (tensile and flexural) analyses, respectively. The findings suggest that of all the parameters, fibre orientation has the most significant impact on the damping, and the maximum loss factor (i.e., 4.3-5.5%) is obtained for 45° and 60° fibre orientations. However, there is no significant difference in loss factors among the composites with different fibre contents. The loss factors lie mainly in the range of 4-5.5%, irrespective of the fibre volume fraction, fibre orientation, and frequency. A significant improvement (281 to 953%) in damping is feasible in flax fibre/polypropylene composites relative to more widespread glass/epoxy composites. The mechanical properties of composites are also strongly affected by fibre orientation with respect to the loading direction; for example, the tensile modulus decreases from 20 GPa to 3.45 GPa at an off-axis angle of 30° for a fibre volume fraction of 0.40. The largest mechanical properties (tensile and flexural) are found in the case of 0° fibre orientation. For composites with fibre volume fractions in the range 0.31-0.50, tensile moduli are in the range 16-21 GPa, and tensile strengths are in the range 125-173 MPa, while flexural moduli and strengths are in the ranges 12-15 GPa and 96-121 MPa, respectively, making them suitable for structural applications. The obtained results also suggest that flax fibre composites are comparable to glass fibre composites, especially in terms of specific stiffness. The ESEM analysis confirms the tensile failures of specimens due to fibre debonding, fibre pull-out and breakage, matrix cracking, and inadequate fibre/matrix adhesion. The outcomes from this study indicate that flax fibre-reinforced composite could be a commercially viable material for applications in which noise and vibration are significant issues and where a significant amount of damping is required with a combination of high stiffness and low weight.

9.
Nanomaterials (Basel) ; 13(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36903724

RESUMO

Graphene is a two-dimensional (2D) material with a single atomic crystal structure of carbon that has the potential to create next-generation devices for photonic, optoelectronic, thermoelectric, sensing, wearable electronics, etc., owing to its excellent electron mobility, large surface-to-volume ratio, adjustable optics, and high mechanical strength. In contrast, owing to their light-induced conformations, fast response, photochemical stability, and surface-relief structures, azobenzene (AZO) polymers have been used as temperature sensors and photo-switchable molecules and are recognized as excellent candidates for a new generation of light-controllable molecular electronics. They can withstand trans-cis isomerization by conducting light irradiation or heating but have poor photon lifetime and energy density and are prone to agglomeration even at mild doping levels, reducing their optical sensitivity. Graphene derivatives, including graphene oxide (GO) and reduced graphene oxide (RGO), are an excellent platform that, combined with AZO-based polymers, could generate a new type of hybrid structure with interesting properties of ordered molecules. AZO derivatives may modify the energy density, optical responsiveness, and photon storage capacity, potentially preventing aggregation and strengthening the AZO complexes. They are potential candidates for sensors, photocatalysts, photodetectors, photocurrent switching, and other optical applications. This review aimed to provide an overview of the recent progress in graphene-related 2D materials (Gr2MS) and AZO polymer AZO-GO/RGO hybrid structures and their synthesis and applications. The review concludes with remarks based on the findings of this study.

10.
Sci Rep ; 13(1): 11151, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429953

RESUMO

Severe failure of improperly designed and poorly constructed structures may occur due to the amplified and prolonged ground motion during an earthquake, and hence prediction of the ground motion characteristics at the soil surface is crucial. In this study, based on the prepared simplified engineering geomorphic map, we performed a one-dimensional (1D) nonlinear site response analysis for seismic site characterization of the recently proposed Detailed Area Plan (DAP) area of Dhaka City, the Capital of Bangladesh. The engineering geomorphic unit-based map was prepared from image analysis and verified with the collected borehole data and surface geology map. The study area was classified into three major geomorphic units and seven sub-units subject to the subsurface soil profiles. Nine earthquake time histories, seven from the PEER NGA WEST2 data set and two synthetics, and seven identified subsurface soil profiles were used for nonlinear site response analysis, along with the BNBC 2020 uniform hazard spectrum as the target spectrum. For the selected earthquake ground motions, the near-surface soil response of the DAP area showed de-amplification of acceleration in the short period and amplification of acceleration in the long period. The amplified long-period acceleration could cause severe damage in inappropriately designed and poorly constructed long-period structures. The outcome of this study could be used to prepare a seismic risk-sensitive land use plan for the future development of the DAP of Dhaka City.

11.
Environ Sci Pollut Res Int ; 30(29): 73061-73086, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37202640

RESUMO

A wildfire, an unplanned fire that is mainly uncontrolled and originates in combustible vegetation in rural or urban settings, is one of the most pervasive natural catastrophes in some areas, such as Siberia, California and Australia. Many studies, such as standard reviews, have been undertaken to look into the works of literature on wildfires or forest fires and their effects on aquatic and terrestrial ecosystems. Regrettably, conventional literature reviews failed to identify the important researchers, evolving complexities, emerging research hotspots, trends and opportunities for further research on the ground of wildfire study. The present study employs bibliometric analysis to investigate this study area qualitatively and quantitatively. The Scopus database systems and Web of Science Core Collection yielded 78 qualifying papers, which were then evaluated using Biblioshiny (A bibliometrix tool of R-studio). According to the statistics, the discipline is expanding at a pace that is 13.68% faster than average. So far, three key periods of transformation have been documented: preliminary evolution (8 articles; 1999-2005), gentle evolution (14 articles; 2006-2013) and quick evolution (56 articles; 2014 to 2021). Forest Ecology and Management and Science journals have the highest number of publications, accounting for 7.70% of total wildfire-related articles published from 1999 to 2021. However, recent data indicate that investigators are shifting their focus to wildfires, with the term 'Australia' having the highest frequency (91) and 'wildfire' having the second highest (58) as the most appeared keywords. The present study will provide a foundation for future research on wildfire incidence and management by receiving information by synthesising previously published literature in Australia and around the world.


Assuntos
Incêndios , Incêndios Florestais , Ecossistema , Florestas , Bibliometria
12.
J Adv Vet Anim Res ; 9(4): 649-662, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36714521

RESUMO

Indigenous sheep are highly adaptable and widely distributed in different regions of Bangladesh. They are famous for their tolerance to harsh environmental conditions, low demand for feed, and disease resistance with minimum or no housing and management facilities. Ample indiscriminate research reports and case studies on the native sheep of Bangladesh have been published. Nonetheless, a comprehensive review of reproductive and productive performances, as well as their various morphometric physiognomies and climate resilience capabilities, is lacking. This review was designed to explore and summarize the available research reports on indigenous sheep to highlight the gaps and provide an updated database for the future research plan for sustainable native sheep production in Bangladesh. It covers studies on sheep biodiversity, their adaptability to the local environment, morphometric features, feeding and nutrition, reproduction and production performances, diseases and health management, and the problems and prospects of sheep farming in Bangladesh. Due to the increased demand for animal protein, especially red meat, the scope of sheep farming increases along with that of other large and small ruminants. The vital constraints of sheep production in Bangladesh include insufficient feed and fodder supply with its high prices, higher disease occurrence with low or no management practices, kid mortality, and a poor marketing channel with the lower popularity of sheep meat than goat meat. Future research would be a prerequisite to measuring the impact of native sheep on household economies and food security during the year, evaluating the other challenges, and finding out the possible interventions in the fields of nutrition, reproduction, and health management.

13.
Polymers (Basel) ; 14(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35406172

RESUMO

Increasingly prevalent respiratory infectious diseases (e.g., COVID-19) have posed severe threats to public health. Viruses including coronavirus, influenza, and so on can cause respiratory infections. A pandemic may potentially emerge owing to the worldwide spread of the virus through persistent human-to-human transmission. However, transmission pathways may vary; respiratory droplets or airborne virus-carrying particles can have a key role in transmitting infections to humans. In conjunction with social distancing, hand cleanliness, and other preventative measures, the use of face masks is considered to be another scientific approach to combat ubiquitous coronavirus. Different types of face masks are produced using a range of materials (e.g., polypropylene, polyacrylonitrile, polycarbonate, polyurethane, polystyrene, polyester and polyethylene) and manufacturing techniques (woven, knitted, and non-woven) that provide different levels of protection to the users. However, the efficacy and proper disposal/management of the used face masks, particularly the ones made of non-biodegradable polymers, pose great environmental concerns. This review compiles the recent advancements of face masks, covering their requirements, materials and techniques used, efficacy, challenges, risks, and sustainability towards further enhancement of the quality and performance of face masks.

14.
Mar Pollut Bull ; 175: 113274, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066413

RESUMO

Quantification of four toxic metals (As, Cr, Cd, and Pb) in water and sediments at the Sitakunda ship breaking area in Bangladesh was studied. Along with this, sediment quality and ecological risk were evaluated for the metal intrusion to the study area. A total sample number of 120 (water; n = 60 and sediment; n = 60) were analyzed for both winter and summer seasons using atomic absorption spectrophotometer (AAS). The trace metal concentration in both water and sediment showed decreasing trend as follows; Cr (mean-W: 0.118 mg/L; mean-S:121.87 mg/kg) > Pb (mean-W: 0.064 mg/L; mean-S: 65.31 mg/kg) > As (mean-W: 0.03 mg/L; mean-S: 32.53 mg/kg) > Cd (mean-W: 0.004 mg/L; mean-S: 4.81 mg/kg). However, in both segments, the concentrations of the toxic metals exceeded the recommended acceptable limits. As and Cd showed significant variation (water and sediment) between the seasons, while Pb and Cr had no seasonal impact. Metal pollution index (MPI) and contamination factor (CF) was evaluated and revealed that the study area exhibited the critical score of water quality (MPI > 100). The cumulative effect of the metal concentrations was high (CI > 3). The assessed mean geoaccumulaiton index (Igeo) revealed that the study area was moderate to strongly polluted except for Cr. According to the contamination factor (CF), the sediment samples were moderate to highly contaminated by Cd, Pb, and As. Moreover, the explored range of pollution load index (PLI) in all sampling sites in the ship breaking region was from 1.75 to 3.10, suggesting that the sediment in the study area was highly polluted by heavy metals (PLI > 1). The risk index and the potential ecological risk index (PERI) suggested that the study area was at high risk due to metals pollution. Therefore, it is obligatory to maintain some crucial efforts for the betterment of the surrounding environment near the investigated sites.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Bangladesh , Baías , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Medição de Risco , Navios , Poluentes Químicos da Água/análise , Qualidade da Água
15.
Environ Sci Pollut Res Int ; 29(26): 40131-40145, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35118591

RESUMO

The release of toxic metals in the water creates an adverse condition for the living organisms (e.g., fish). The aim of this research was to learn more about the spatiotemporal variations and toxicity of heavy metals (As, Cr, Cd, and Pb) among fish species that are economically important (Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, Harpadon nehereus, Pseudapocryptes elongatus, Polynemus paradiseus, and Sillaginopsis panijus) collected from Pasur River. Heavy metal (HMs) concentrations were evaluated using the atomic absorption spectrometry (AAS) technique. Most of the metals showed no significant variation spatiotemporally (p ˃ 0.05) except As and Cr showed substantial variation in terms of seasons (p ˂ 0.05). All fish species' Cr and Pb concentrations, as well as As and Cd values, were estimated to be greater than FAO/WHO tolerable concentrations, implying that these metals pose danger to humans. HM has a total hazard quotient (THQ) value in individual fish species reported to be greater than 1, whereas an individual metal, arsenic, exceeds the standard value (THQ > 1), causing a significant noncarcinogenic issue in the study region. The target hazard (TR) value for As and Pb exceeds the USEPA norm (10-4) suggesting that long-term consumption of fish poses a chronic cancer risk to the people in the study field. According to the findings, the fish in the Pasur River are unfit for human consumption. The correlation matrix (CM) indicates that sources of metals are similar (e.g., industries, ships, agricultural inputs, etc.).


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Animais , Bangladesh , Cádmio/análise , Monitoramento Ambiental , Peixes , Contaminação de Alimentos/análise , Humanos , Chumbo/análise , Metais Pesados/análise , Medição de Risco , Rios/química , Oligoelementos/análise , Poluentes Químicos da Água/análise
16.
Environ Sci Pollut Res Int ; 29(14): 20112-20127, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34727308

RESUMO

The chemical contaminants in dried fish are of great food safety concern and an emerging public health issue in Bangladesh. The aim of this study was to assess the public health risk associated with exposure to pesticides (organochlorine and organophosphorus) and heavy metals (lead, mercury, cadmium, chromium, arsenic) through the consumption of dried fish (Bombay duck, ribbon fish, silver jewfish, shrimp, Chinese promfret) in coastal districts (Cox's Bazar, Chittagong, Bhola, Patuakhali, Khulna) of Bangladesh. Dried fish consumption data were collected from 500 adult respondents (100 from each district) using a food frequency questionnaire (FFQ). Pesticide residues were determined using QuEChERS extraction coupled to gas chromatography and gas chromatography mass spectrometry, and heavy metals were estimated using an atomic absorption spectrophotometric method. The results revealed that the frequency and amount of dried fish consumption was highest for Bombay duck in Cox's Bazar (11.57 g/capita/day) and ribbon fish (12.10 g/capita/day) in Chittagong. The estimated daily intake (EDI, 7.40 × 10-5 to 1.10 × 10-4 mg/kg/day) and health risk index (HRI, 0.013 to 0.16) values expressed no health risk from pesticide residues in all the positive samples. For heavy metals, target hazard quotients (THQ) for non-carcinogenic health risk were below 1 (0.001-0.154), indicating no health risk for all samples. However, carcinogenic risk R value indicated a potential health risk for chromium (2.64 × 10-6 to 4.06 × 10-6), and carcinogenic RT value (2.82 × 10-6 to 5.71 × 10-6) indicated a potential health risk for all the metals. It is concluded that the risk of exposure to pesticides through the consumption of dried fish is low, while heavy metals pose moderate-to-high health risks to dried fish consumers in the study area. Thus, the study suggests an appropriate risk management policy that controls pesticides and heavy metals in dried fish to ensure safe food for local and global consumers, underpinned by a producers' capacity building and consumers' awareness raising strategy.


Assuntos
Metais Pesados , Praguicidas , Poluentes Químicos da Água , Animais , Bangladesh , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Metais Pesados/análise , Praguicidas/análise , Saúde Pública , Medição de Risco/métodos , Poluentes Químicos da Água/análise
17.
Chemosphere ; 301: 134660, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35469901

RESUMO

Contamination of fish with heavy metals (Heavy metals) is one of the most severe environmental and human health issues. However, the contamination levels in tropical fishes from Bangladesh are still unknown. To this end, the evaluated concentrations of arsenic (As), chromium (Cr), cadmium (Cd), and lead (Pb) in 12 different commercially important fish species (Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Glossogobius giuris, Pseudeutropius atherinoides, Polynemus paradiseus, Sillaginopsis panijus, Corica soborna, Amblypharyngodon mola, Trichogaster fasciata, and Wallago attu) were collected from the Kirtankhola River assess human health risk for the consumers, both in the summer and winter seasons. Toxic metals surpassed the acceptable international limits in P. atherinoides, P. paradiseus, S. panijus, C. soborna, and W. attu. The target hazard quotient (THQ) revealed that non-carcinogenic health effects (HI < 1) for children and adults, and the carcinogenic risk (CR) indicated safety. Results show that children are more susceptible to carcinogenic and non-carcinogenic hazards from higher As. The multivariate analysis justified that heavy metals were from anthropogenic actions. The lessening of toxic metals might need strict rules and regulations as metal enrichment would continue to increase in this tidal river from both the anthropogenic and natural sources.


Assuntos
Arsênio , Metais Pesados , Poluentes Químicos da Água , Animais , Arsênio/análise , Bangladesh , Carcinógenos/análise , Monitoramento Ambiental , Peixes , Metais Pesados/análise , Medição de Risco , Rios , Estações do Ano , Impostos , Poluentes Químicos da Água/análise
18.
Acta Biomater ; 121: 41-67, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33285327

RESUMO

Natural protection offered to living beings is the result of millions of years of biological revolution. The protections provided in fishes, armadillos, and turtles by unique hierarchal designs help them to survive in surrounding environments. Natural armors offer protections with outstanding mechanical properties, such as high penetration resistance and toughness to weight ratio. The mechanical properties are not the only key features that make scales unique; they are also highly flexible and breathable. In this study, we aim to review the structural and mechanical characteristics of the scales from ray-finned or teleost fishes, which can be used for new bio-inspired armor designs. It is also essential to consider the hierarchical structure of extinct and existing natural armors. The basic characteristics, as mentioned above, are the foundation for developing high-performance, well-structured flexible natural armors. Furthermore, the present review justifies the importance of interaction between toughness, hardness, and deformability in well-engineered bio-inspired body armor. At last, some suggestions are proposed for the design and fabrication of new bio-inspired flexible body armors.


Assuntos
Peixes , Tartarugas , Animais , Dureza
19.
Iran J Pathol ; 16(4): 362-369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567184

RESUMO

BACKGROUND & OBJECTIVE: Vascular Endothelial Growth Factor (VEGF) is one of the newer molecular markers that acts as a central mediator of tumor angiogenesis and is essential for tumor growth, progression, and metastasis. So anti-angiogenic drugs can be used as anticancer therapy. Treatments with anti-VEGF (Bevacizumab) therapy have been proved to improve relapse-free survival in many tumors. Urinary bladder tumor has become emerging cancer globally among elderly individuals. So, the identification and development of novel biomarkers for effective treatment of urinary bladder carcinoma is essential. The present study aimed to investigate the immunohistochemical expression of VEGF in urothelial carcinoma of urinary bladder and to assess its association with tumor grade and muscle invasiveness. METHODS: This cross-sectional study was conducted in the Department of Pathology, Chittagong Medical College, Chattogram from September 2018 to August 2020. Fifty-six formalin-fixed paraffin-embedded tissue blocks of urinary bladder carcinoma were prepared for both histopathological and immunohistochemical examination. Each slide was evaluated by at least two pathologists. RESULTS: Weak to strong positive expression of VEGF were observed in 52 cases (92.86%). The proportion of tumors positive for VEGF expression was higher among patients with high grade and non-muscle invasive bladder carcinoma. CONCLUSION: We found that VEGF expression has a significant association with tumor grade and an inverse association with muscle invasion. These findings may be useful for selecting the subset of patients likely to respond to anti-VEGF targeted therapy.

20.
Plants (Basel) ; 10(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34834656

RESUMO

Sesame is sensitive to waterlogging, and its growth is devastatingly impacted under excess moisture conditions. Thus, waterlogging tolerance is crucial to alleviate yield constraints, particularly under expected climate change. In this study, 119 diverse sesame genotypes were screened for their tolerance to 12, 24, 48, and 72 h of waterlogging relative to non-waterlogged conditions. All plants died under 72 h of waterlogging, while 13.45%, 31.93%, and 45.38% of genotypes survived at 48, 24, and 12 h, respectively. Based on the seedling parameters and waterlogging tolerance coefficients, genotypes BD-7008 and BD-6985 exhibited the highest tolerance to waterlogging, while BD-6996 and JP-01811 were the most sensitive ones. The responses of these four genotypes to waterlogged conditions were assessed at different plant growth stages-30, 40, and 50 days after sowing (DAS)-versus normal conditions. Waterlogging, particularly when it occurred within 30 DAS, destructively affected the physiological and morphological characteristics, which was reflected in the growth and yield attributes. Genotype BD-7008, followed by BD-6985, exhibited the highest chlorophyll and proline contents as well as enzymatic antioxidant activities, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). These biochemical and physiological adjustments ameliorated the adverse effects of waterlogging, resulting in higher yields for both genotypes. Conversely, JP-01811 presented the lowest chlorophyll and proline contents as well as enzymatic antioxidant activities, resulting in the poorest growth and seed yield.

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