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1.
Chemosphere ; 352: 141248, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280643

RESUMO

Anthracene belongs to the polycyclic aromatic hydrocarbon (PAH) consisting of benzene rings, unusually highly stable through more π-electrons and localized π-bond in entire rings. Aqueous-phase anthracene adsorption using carbon-based materials such as biochar is ineffective. In this paper, carbon dots (CDs) derived from the acid treatment of coconut shell biochar (CDs/MCSB) decorated with chitosan (CS) are successfully synthesized and applied for anthracene removal from aqueous solutions. The h-CDs/MCSB exhibited fast adsorption of anthracene with significant sorption capacity (Qmax = 49.26 mg g-1) with 95 % removal efficiency at 60 min. The study suggested chemisorption dominated monolayer anthracene adsorption onto h-CDs/MCSB, where a significant role was played by ion-exchange. Density Functional Theory (DFT) suggested the anthracene adsorption was dominated by the electrostatic interactions and delocalized electron, induced by higher polarizability of functional groups on the surface of hybrid CDs/MCSB assisted by chitosan (h-CDs/MCSB). In addition, the aromatic structure of CDs/MCSB and high polarizability of functional groups provided the strong interactions between benzene rings of anthracene and hybrid adsorbent-assisted multiple π-bond through delocalized π-bond and polarization-induced H-bond interactions. The presence of carboxylic and sulfonic groups on the CDs/MCSB surface also contributed to the effective adsorption of anthracene was confirmed by the fluorescence spectra. The results showed that the hybrid adsorbent was an effective material for removing PAHs, usually difficult to remove from water owing to the presence of benzene rings in their structures. Further, consistency in the DFT results suggested the outstanding binding capacity with the anthracene molecules with h-CDs/MCSB.


Assuntos
Quitosana , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Carbono , Adsorção , Água , Benzeno , Carvão Vegetal/química , Antracenos , Poluentes Químicos da Água/química , Cinética
2.
Heliyon ; 9(11): e21245, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954389

RESUMO

Land use land cover change (LULC) significantly impacts urban sustainability, urban planning, climate change, natural resource management, and biodiversity. The Chattogram Metropolitan Area (CMA) has been going through rapid urbanization, which has impacted the LULC transformation and accelerated the growth of urban sprawl and unplanned development. To map those urban sprawls and natural resources depletion, this study aims to monitor the LULC change using Landsat satellite imagery from 2003 to 2023 in the cloud-based remote sensing platform Google Earth Engine (GEE). LULC has been classified into five distinct classes: waterbody, build-up, bare land, dense vegetation, and cropland, employing four machine learning algorithms (random forest, gradient tree boost, classification & regression tree, and support vector machine) in the GEE platform. The overall accuracy (kappa statistics) and the receiver operating characteristic (ROC) curve have demonstrated satisfactory results. The results indicate that the CART model outperforms other LULC models when considering efficiency and accuracy in the designated study region. The analysis of LULC conversions revealed notable trends, patterns, and magnitudes across all periods: 2003-2013, 2013-2023, and 2003-2023. The expansion of unregulated built-up areas and the decline of croplands emerged as primary concerns. However, there was a positive indication of a significant increase in dense vegetation within the study area over the 20 years.

3.
Proc Inst Mech Eng H ; 237(11): 1297-1305, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37924244

RESUMO

Clinical fixation screws are common in clinical practices to fix mandibular condyle fractures. Evidence suggests significance of 'working length' that is, distance between proximal and distal fixation screws in proximity to the fracture in orthopaedic implant design. In pursuit of stable implant-bone construct, this study aims to investigate the biomechanical performance of each configuration considered in the study and provide an optimal working length between the screws for clinical reference. Finite element models of virtually designed broken condyle as type 'B' were simulated and analysed in ANSYS Workbench. Screws are implanted according to previous literature at five varied distances 'd' maintaining five different ratios with the fracture length 'D'. Based on a literature review, boundary conditions, muscle traction forces and non-linear contacts were assigned to obtain precise results. Each case is considered an individual configuration and von Mises distribution, microstrain in bone, screw-bone interface micromotion and fracture dislocation were evaluated for all these configurations. Stress-shielding phenomenon is observed for maximum von Mises stresses in bone. Microstrain concentration was significant in cancellous bone in the vicinity of the screw around the fracture line. Configurations were compared based on the stress-strain along with micromotion to support the required amount of osseointegration between implant and bone. Presented data from all five conditions supported the assumption that under physiological loading conditions, the D3 configuration provided stability for fracture healing. Further research on screw shapes, diameters and material properties, or investigating the direction of forces within the screws could provide further insight into this topic.


Assuntos
Parafusos Ósseos , Fixação Interna de Fraturas , Análise de Elementos Finitos , Fenômenos Biomecânicos , Placas Ósseas , Osso Esponjoso
4.
J Environ Health Sci Eng ; 21(2): 319-332, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37869606

RESUMO

Purpose: The aim of this study was to evaluate the effectiveness of nitrilotriacetic acid (NTA) on cadmium (Cd) fractions and microbial biomass in a calcareous soil spiked with Cd under cultivated (Zea mays L.) and uncultivated regime subject to soil leaching condition. Expanding investigations related to soil-plant interactions on metal-contaminated soils with insights on microbial activity and associated soil toxicity perspective provides novel perspectives on using metal-chelating agents for soil remediation. Methods: The experimental factors were three levels of Cd contamination (0, 25, and 50 mg kg-1 soil) and three levels of NTA (0, 15, and 30 mmol L-1) in loamy soil under maize-cultured and non-cultured conditions. During the experiment, the adding NTA and leaching processes were performed three times. Results: The results showed that the amount of leached Cd decreased in cultivated soil compared to uncultivated soil due to partial uptake of soluble Cd by plant roots and changes in Cd fractions in soil, so that Cd leached in Cd50NTA30 was 9.2 and 6.1 mg L-1, respectively, in uncultivated and cultivated soils. Also, Cd leached in Cd25NTA30 was 5.7 and 3.1 mg L-1 respectively, in uncultivated and cultivated soils. The best treatment in terms of chemical and microbial characteristics of the soil with the high percentage of Cd removed from the soil was Cd25NTA30 in cultivated soil. In Cd25NTA30 compared to Cd25NTA0 in cultivated soil, pH (0.25 unit), microbial biomass carbon (MBC, 65.0 mg kg-1), and soil respiration (27.5 mg C-CO2 kg-1 24 h-1) decreased, while metabolic quotient (qCO2, 0.05) and dissolved organic carbon (DOC, 20.0 mg L-1) increased. Moreover, the changes of Cd fractions in Cd25NTA30 in cultivated soil compared to uncultivated soil were as follows; the exchangeable Cd (F1, 0.27 mg kg-1) and Fe/Mn-oxide-bounded Cd (F4, 0.15 mg kg-1) fractions increased, in contrast, carbonate-Cd (F2, 2.67 mg kg-1) and, organically bounded Cd (F3, 0.06 mg kg-1) fractions decreased. NTA had no significant effect on the residual fraction (F5). Conclusion: The use of NTA, especially in calcareous soils, where most of the Cd is bound to calcium carbonate, was able to successfully convert insoluble fractions of Cd into soluble forms and increase the removal efficiency of Cd in the phytoremediation method. NTA is a non-toxic chelating agent to improve the accumulation of Cd in maize.

5.
Sci Total Environ ; 904: 166165, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37574065

RESUMO

Microplastics (MPs) are a new and lesser-known pollutant that has intrigued the interest of scientists all over the world in recent decades. MP (<5mm in size) can enter marine environments such as mangrove forests in a variety of ways, interfering with the health of the environment and organisms. Mangroves are now getting increasingly exposed to microplastic contamination due to their proximity to human activities and their position as critical transitional zones between land and sea. The present study reviews the status of MPs contamination specifically in mangrove ecosystems situated in Asia. Different sources and characteristics of MPs, subsequent deposition of MPs in mangrove water and sediments, bioaccumulation in different organisms are discussed in this context. MP concentrations in sediments and organisms were higher in mangrove forests exposed to fishing, coastal tourism, urban, and industrial wastewater than in pristine areas. The distribution of MPs varies from organism to organism in mangrove ecosystems, and is significantly influenced by their morphometric characteristics, feeding habits, dwelling environment etc. Mangrove plants can accumulate microplastics in their roots, stem and leaves through absorption, adsorption and entrapment helping in reducing abundance of microplastic in the surrounding environment. Several bacterial and fungal species are reported from these mangrove ecosystems, which are capable of degrading MPs. The bioremediation potential of mangrove plants offers an innovative and sustainable approach to mitigate microplastic pollution. Diverse mechanisms of MP biodegradation by mangrove dwelling organisms are discussed in this context. Biotechnological applications can be utilized to explore the genetic potential of the floral and faunal species found in the Asian mangroves. Detailed studies are required to monitor, control, and evaluate MP pollution in sediments and various organisms in mangrove ecosystems in Asia as well as in other parts of the world.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Ecossistema , Bioacumulação , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Ásia
6.
Environ Pollut ; 334: 122171, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437759

RESUMO

In light of the current COVID-19 pandemic caused by the virus SARS-CoV-2, there is an urgent need to identify and investigate the various pathways of transmission. In addition to contact and aerosol transmission of the virus, this review investigated the possibility of its transmission via microplastics found in sewage. Wastewater-based epidemiological studies on the virus have confirmed its presence and persistence in both influent sewage as well as treated ones. The hypothesis behind the study is that the huge amount of microplastics, especially Polyvinyl Chloride and Polyethylene particles released into the open waters from sewage can become a good substrate and vector for microbes, especially Polyvinyl Chloride and Polyethylene particles, imparting stability to microbes and aiding the "plastisphere" formation. A bibliometric analysis highlights the negligence of research toward plastispheres and their presence in sewage. The ubiquity of microplastics and their release along with the virus into the open waters increases the risk of viral plastispheres. These plastispheres may be ingested by aquatic organisms facilitating reverse zoonosis and the commercial organisms already reported with accumulating microplastics through the food chain poses a risk to human populations as well. Reliance of high population density areas on open waters served by untreated sewage in economically less developed countries might bring back viral transmission.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Esgotos , Microplásticos , Águas Residuárias , Plásticos , Pandemias , Cloreto de Polivinila , Polietileno
7.
Environ Monit Assess ; 195(7): 818, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286743

RESUMO

The nature and intensity of water pollution determine the effects on aquatic biota and aquatic ecosystem health. The present study aimed at assessing the impact of the degraded physicochemical regime of river Saraswati, a polluted river having a historical legacy, on the parasitic infection and the role of fish parasite as a bioindicator of water quality. Two Water Quality Indices (WQIs) were adopted as useful tools for assessing the overall water quality status of polluted river based on 10 physicochemical parameters. Total 394 fish (Channa punctata) were examined. Ectoparasite Trichodina sp., Gyrodactylus sp., and endoparasites Eustrongylides sp. were collected from the host fish. Prevalence, mean intensity and abundance for each sampling period were calculated for the determination of parasitic load. The parasitic load of Trichodina sp. and Gyrodactylus sp. was significantly (p < 0.001) higher in winter, whereas the parasitic load of Eustrongylides sp. showed no significant (p > 0.05) seasonal fluctuation. The parasitic load of ectoparasites was negatively correlated with temperature, free carbon dioxide, biochemical oxygen demand, and WAWQI but positively correlated with electrical conductivity and CCMEWQI. Fish health was found to be adversely affected by degrading water qualities and parasitic infection. A 'vicious cycle' develops as a result of the interplay among deteriorating water quality, withering fish immunological defence, and amplifying parasitic infection. Since parasitic load was strongly conditioned by the combined influence of a suite of water quality parameters the fish parasites can be used as a powerful indicator of deteriorating water quality.


Assuntos
Biomarcadores Ambientais , Monitoramento Ambiental , Peixes , Parasitos , Animais , Ecossistema , Peixes/parasitologia , Rios/parasitologia , Qualidade da Água , Índia
8.
Ann Hepatobiliary Pancreat Surg ; 27(4): 350-365, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37336782

RESUMO

Backgrounds/Aims: Extra hepatic portal venous obstruction (EHPVO) is the most common cause of portal hypertension in Indian children. While endoscopy is the primary modality of management, a subset of patients require surgery. This study aims to report the short- and long-term outcomes of EHPVO patients managed surgically. Methods: All the patients with EHPVO who underwent surgery between August 2007 and December 2021 were retrospectively reviewed. Postoperative complications were classified after Clavien-Dindo. Binary logistic regression in Wald methodology was used to determine the predictive factors responsible for unfavourable outcome. Results: Total of 202 patients with EHPVO were operated. Mean age of patients was 20.30 ± 9.96 years, and duration of illness, 90.05 ± 75.13 months. Most common indication for surgery was portal biliopathy (n = 59, 29.2%), followed by bleeding (n = 50, 24.8%). Total of 166 patients (82.2%) had shunt procedure. Splenectomy with esophagogastric devascularization was the second most common surgery (n = 20, 9.9%). Nine major postoperative complications (Clavien-Dindo > 3) were observed in 8 patients (4.0%), including 1 (0.5%) operative death. After a median follow-up of 56 months (15-156 months), 166 patients (82.2%) had favourable outcome. In multivariate analysis, associated splenic artery aneurysm (p = 0.007), isolated gastric varices (p = 0.004), preoperative endoscopic retrograde cholangiography and stenting (p = 0.015), and shunt occlusion (p < 0.001) were independent predictors of unfavourable long-term outcome. Conclusions: Surgery in EHPVO is safe, affords excellent short- and long-term outcome in patients with symptomatic EHPVO, and may be considered for secondary prophylaxis.

9.
J Environ Manage ; 343: 118221, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37245308

RESUMO

Jarosite is a residue that is generated as a by-product during zinc extraction, and it consists of various types of heavy metal (loid)s such as arsenic, cadmium, chromium, iron, lead, mercury and silver. Due to the huge jarosite turn-over rate, and less efficient and expensive residual metal extraction processes, the zinc-producing industries dispose this waste in landfills. However, the leachate generated from such landfills contains a high concentration of heavy metal (loid)s that could contaminate the nearby water resources and cause environmental concern and human health risk. Various thermo-chemical and biological processes have been developed for the recovery of heavy metals from such waste. In this review, we have discussed all those pyrometallurgical, hydrometallurgical, and biological. Those studies were critically reviewed and compared on the basis of their techno-economic differences. The review indicated that these processes have their own benefits and drawbacks such as overall yield, economic and technical constraints, and the need for more than one process to mobilize multiple metal ions from jarosite. Also, in this review, the residual metal extraction processes from jarosite waste have been linked with the relevant UN Sustainable Development Goals (SDGs), which can be useful for a better approach to sustainable development.


Assuntos
Fenômenos Bioquímicos , Metais Pesados , Humanos , Compostos Férricos/química , Zinco
10.
Environ Dev Sustain ; : 1-12, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36785714

RESUMO

There has been a long-lasting impact of the lockdown imposed due to COVID-19 on several fronts. One such front is climate which has seen several implications. The consequences of climate change owing to this lockdown need to be explored taking into consideration various climatic indicators. Further impact on a local and global level would help the policymakers in drafting effective rules for handling challenges of climate change. For in-depth understanding, a temporal study is being conducted in a phased manner in the New Delhi region taking NO2 concentration and utilizing statistical methods to elaborate the quality of air during the lockdown and compared with a pre-lockdown period. In situ mean values of the NO2 concentration were taken for four different dates, viz. 4th February, 4th March, 4th April, and 25th April 2020. These concentrations were then compared with the Sentinel (5p) data across 36 locations in New Delhi which are found to be promising. The results indicated that the air quality has been improved maximum in Eastern Delhi and the NO2 concentrations were reduced by one-fourth than the pre-lockdown period, and thus, reduced activities due to lockdown have had a significant impact. The result also indicates the preciseness of Sentinel (5p) for NO2 concentrations.

11.
Environ Res ; 220: 115098, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586716

RESUMO

Cadmium (Cd), a major contaminant of concern, has been extensively reviewed and debated for its anthropogenic global shifts. Cadmium levels in rice grains raise wide food safety concerns. The aim of this review is therefore to capture the dynamics of Cd in paddy soil, translocation pathways of Cd from soil to consumption rice, and assess its bio-accessibility in human consumption. In crop plants, Cd reduces absorption of nutrients and water, triggers oxidative stress, and inhibits plant metabolism. Understanding the mechanisms and behaviour of Cd in paddy soil and rice allows to explain, predict and intervene in Cd transferability from soil to grains and human exposure. Factors affecting Cd movement in soil, and further to rice grain, are elucidated. Recently, physiological and molecular understanding of Cd transport in rice plants have been advanced. Morphological-biochemical characteristics and Cd transporters of plants in such a movement were also highlighted. Ecologically viable remediation approaches, including low input cost agronomic methods, phytoremediation and microbial bioremediation methods, are emerging.


Assuntos
Oryza , Poluentes do Solo , Humanos , Cádmio/toxicidade , Cádmio/análise , Oryza/química , Solo/química , Agricultura , Biodegradação Ambiental , Poluentes do Solo/análise
12.
Environ Res ; 216(Pt 2): 114496, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257453

RESUMO

The emergence of novel respiratory disease (COVID-19) caused by SARS-CoV-2 has become a public health emergency worldwide and perturbed the global economy and ecosystem services. Many studies have reported the presence of SARS-CoV-2 in different environmental compartments, its transmission via environmental routes, and potential environmental challenges posed by the COVID-19 pandemic. None of these studies have comprehensively reviewed the bidirectional relationship between the COVID-19 pandemic and the environment. For the first time, we explored the relationship between the environment and the SARS-CoV-2 virus/COVID-19 and how they affect each other. Supporting evidence presented here clearly demonstrates the presence of SARS-CoV-2 in soil and water, denoting the role of the environment in the COVID-19 transmission process. However, most studies fail to determine if the viral genomes they have discovered are infectious, which could be affected by the environmental factors in which they are found.The potential environmental impact of the pandemic, including water pollution, chemical contamination, increased generation of non-biodegradable waste, and single-use plastics have received the most attention. For the most part, efficient measures have been used to address the current environmental challenges from COVID-19, including using environmentally friendly disinfection technologies and employing measures to reduce the production of plastic wastes, such as the reuse and recycling of plastics. Developing sustainable solutions to counter the environmental challenges posed by the COVID-19 pandemic should be included in national preparedness strategies. In conclusion, combating the pandemic and accomplishing public health goals should be balanced with environmentally sustainable measures, as the two are closely intertwined.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Ecossistema , Pandemias , Plásticos , SARS-CoV-2
13.
Am J Surg ; 225(4): 709-714, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36266135

RESUMO

BACKGROUND: The literature on predictors for postoperative complications after Frey procedure (FP) is sparse. The aim of this study is to report our experience with 90-day complications of FP and predictors for complications. METHODS: All patients with chronic pancreatitis (CP), who underwent a FP between August 2007 and July 2021, were retrospectively reviewed. Univariate and multivariate analysis were used to identify predictors of 90-day morbidity and mortality. RESULTS: Of the total 270 patients, 84 (31%) patients developed at least one postoperative complication. Major complications occurred in 32 (12%) patients. Most common complication was wound infection and it was significantly more common in stented patients (p = 0.017). Pancreatic fistula and post pancreatectomy hemorrhage (PPH) developed in 7.4% of patients. Thirteen patients (4.8%) required early re-operation and the most common cause of re-exploration was PPH. 90-day mortality was 1% (n = 3) and all 3 patients required re-exploration for PPH. Median postoperative hospital stay was 9 (5-51) days. Perioperative blood transfusions was the only independent predictor of postoperative complications after FP. CONCLUSIONS: Frey procedure is an acceptable treatment modality with low rates of mortality and reasonable perioperative morbidities. Minimizing blood transfusions may further improve 90-day outcomes.


Assuntos
Pancreatite Crônica , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Pancreatite Crônica/cirurgia , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Complicações Pós-Operatórias/etiologia , Morbidade
14.
Environ Geochem Health ; 45(5): 1555-1572, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35532837

RESUMO

Metal contamination from upstream river water is a threat to coastal and estuarine ecosystem. The present study was undertaken to unveil sedimentation processes and patterns of heavy metal deposition along the salinity gradient of a tropical estuary and its mangrove ecosystem. Sediment columns from three representative sites of differential salinity, anthropogenic interference, and sediment deposition pattern were sampled and analyzed for grain size distribution and metal concentrations as a function of depth. Sediments were dominantly of silty-medium sand texture. A suite of fluvial and alluvial processes, and marine depositional forcing control the sediment deposition and associated heavy metal loading in this estuary. The depth profile revealed a gradual increase in heavy metal accumulation in recent top layer sediments and smaller fractions (silt + clay), irrespective of tidal regimes. Alluvial processes and long tidal retention favor accumulation of heavy metals. Enrichment factor (0.52-15), geo-accumulation index (1.4-5.8), and average pollution load index (PLI = 2.0) indicated moderate to higher heavy metal contamination status of this estuary. This study showed that alluvial processes acted as dominant drivers for the accumulation of metals in sediments, which prevailed over the influence of marine processes. Longer tidal retention of the water column favored more accumulation of heavy metals. Metal accumulation in the sediments entails a potential risk of bioaccumulation and biomagnification through the food web, and may increasingly impact estuarine ecology, economy, and ultimately human health.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Ecossistema , Sedimentos Geológicos , Rios , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Metais Pesados/análise , Estuários , Água , Medição de Risco
15.
J Orthop Sci ; 28(5): 992-1003, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36175251

RESUMO

BACKGROUND: Lumbar pedicle screw is one of the most common and important elements in the field of lumbar surgery. It plays a great role in rectifying the spinal alignment and stabilization providing strength and stability to the affected area of spine. In spinal surgery, minimally invasive techniques and minor incisions are made which makes it less painful for the patients than the traditional methods. Moreover, the screws are not needed to be removed after the surgery which is yet another great advantage of the pedicle screw. METHOD: In this study, 3D Finite Element (FE) model of human L4 vertebrae is taken for analysis using image processing tool. Pedicle screw design with varying mechanical and geometrical properties has been carried out at different applied loads on it along with considering the effect of frictional forces between all contact surfaces. RESULT: Mathematical relationship among stress, strain, pitch of the screw and diameter have been developed for different thread profiles which will be beneficial for researchers for further development of pedicle screw implants. CONCLUSION: Results from the different analysis shows that bending stress on the screw for different loads at triangular pitch is higher than the trapezoidal. Hence, trapezoidal thread is efficacious than triangular thread. In case of vertebral bone, the magnitude of stress is less for trapezoidal screw than triangular and stress has a linear relationship with pitch length. In term of strain, triangular thread develops more strain than trapezoidal thread. A set of mathematical relation has been developed for different thread profile based on pitch length, stress and strain which gives the idea about von Mises stress and strain.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Análise de Elementos Finitos , Fenômenos Biomecânicos , Vértebras Lombares/cirurgia , Processamento de Imagem Assistida por Computador , Fusão Vertebral/métodos
16.
Environ Monit Assess ; 195(1): 201, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36525097

RESUMO

Despite being a historically significant and biologically diverse protected area in Bangladesh, Bhawal National Park (BNP) has been the victim of anthropogenic activities that have challenged its sustainability. This study aims to determine the extent of landscape change and forest area depletion within BNP territory from 2005 to 2020, as land use change is the most visible indicator of human footprint liable to biodiversity loss and land degradation. Landsat satellite images from four sensors are used in this research (MSS, TM, OLI, and TIRS). The complex spatial composition of Bhawal National Park was characterized using a supervised classification technique using ArcMap version 10.8. The findings show a steady decline in the dense and degraded forest classifications, but an increase in the other classed classes. Waterbody, settlement, and chala/baid are found to increase by approximately 105, 369, and 650% respectively from 2005 till 2020, while, the area of dense and degraded forest decreased by about 47 and 51%. Within 16 years, nearly 1000 ha of dense forest cover has been depleted. Comparing the latest classified image of BNP with the relevant map, Bhabanipur, B.K. Bari, and Boupara beat are identified to be the most degraded areas. The conclusion can be drawn from this study that owing to most suppressing factors, namely settlement and chala/baid, a forest cover of nearly 2284 ha has been depleted from this national park which is almost 49% of the total possessed forest cover in 2005.


Assuntos
Conservação dos Recursos Naturais , Parques Recreativos , Humanos , Conservação dos Recursos Naturais/métodos , Bangladesh , Monitoramento Ambiental/métodos , Florestas
17.
Sci Total Environ ; 853: 158562, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36089037

RESUMO

Rising global temperature, pollution load, and energy crises are serious problems, recently facing the world. Scientists around the world are ambitious to find eco-friendly and cost-effective routes for resolving these problems. Biochar has emerged as an agent for environmental remediation and has proven to be the effective sorbent to inorganic and organic pollutants in water and soil. Endowed with unique attributes such as porous structure, larger specific surface area (SSA), abundant surface functional groups, better cation exchange capacity (CEC), strong adsorption capacity, high environmental stability, embedded minerals, and micronutrients, biochar is presented as a promising material for environmental management, reduction in greenhouse gases (GHGs) emissions, soil management, and soil fertility enhancement. Therefore, the current review covers the influence of key factors (pyrolysis temperature, retention time, gas flow rate, and reactor design) on the production yield and property of biochar. Furthermore, this review emphasizes the diverse application of biochar such as waste management, construction material, adsorptive removal of petroleum and oil from aqueous media, immobilization of contaminants, carbon sequestration, and their role in climate change mitigation, soil conditioner, along with opportunities and challenges. Finally, this review discusses the evaluation of biochar standardization by different international agencies and their economic perspective.


Assuntos
Poluentes Ambientais , Gases de Efeito Estufa , Petróleo , Solo/química , Biodiversidade , Temperatura , Carvão Vegetal/química , Água , Micronutrientes
18.
Environ Res ; 214(Pt 3): 113937, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35931193

RESUMO

In this study the multiple metal(loid) (As, Cd, Cu and Ni) resistant bacterium Serratia sp. KUJM3 was able to grow in both single and multiple metal(loid) contaminated wastewater and removed them by 34.93-48.80% and 22.93-32%, respectively. It reduced As(v) to As(III) by 68.44-85.06% in a concentration dependent manner. The strain's IAA production potential increased significantly under both metal(loid)s regime. The lentil (Lens culinaris) seed germination and seed production were enhanced with the exogenous bacterial inoculation by 20.39 and 16.43%, respectively. Under both multi-metal(loid) regimes the bacterial inoculation promoted shoot length (22.65-51.34%), shoot dry weight (33.89-66.11%) and seed production (13.46-35%). Under bacterial manipulation the metal(loid)s immobilization increased with concomitant curtailment of translocation in lentil plant by 61.89-75.14% and 59.19-71.14% in shoot and seed, respectively. The strain biomineralized struvite (MgNH4 PO4 ·6H2O) from human urine @ 403 ± 6.24 mg L-1. The fertilizer potential of struvite was confirmed with the promotion of cowpea (Vigna unguiculata) growth traits e.g. leaf number (37.04%), pod number (234%), plant wet weight (65.47%) and seed number (134.52%). Thus Serratia sp. KUJM3 offers multiple benefits of metal(loid)s bioremediation, As(V) reduction, plant growth promotion, and struvite biomineralization garnering a suite of appealing environmental applications.


Assuntos
Lens (Planta) , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Humanos , Metais , Metais Pesados/análise , Desenvolvimento Vegetal , Serratia , Poluentes do Solo/análise , Estruvita
19.
Updates Surg ; 74(5): 1543-1550, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35840791

RESUMO

The aim of the study is to report the outcomes of reoperative surgery for late failure of postcholecystectomy bile duct injury (BDI) repair. All the patients, who underwent a reoperative surgery for late failure of postcholecystectomy BDI repair at our institution between August 2007 and July 2020, were retrospectively reviewed. Of the total 262 patients of BDI repair, 66 underwent reoperative surgery for late failure. Median duration between last attempt repair and the onset of recurrent symptoms was 18 months. Eighty-five percent of patients with failed repair became symptomatic within 5 years of attempt repair. The most common type of BDI was E3. All the patients underwent Roux-en-Y hepaticojejunostomy. Twenty-nine postoperative complications developed in 23 (35%) patients. Postoperative mortality was 1.5%. Median postoperative hospital stay was 9 (5-61) days. Over a median follow-up of 80 (12-150) months, 5.2% (3/58) of patients developed clinically relevant anastomotic stricture. Three patients with secondary biliary cirrhosis died in the follow-up period due to decompensated liver disease. Overall, excellent or good long-term outcome was achieved in 83% (48/58) of patients which was significantly less satisfactory than primary repair patients (82.8% vs 92.7%, p = 0.039). Reoperative surgery is safe in patients with failed repair after postcholecystectomy BDI and good long-term clinical success can be achieved in most of the patients. The long-term results were less satisfactory in failed-repair group than those who underwent primary repair at our institution. Early referral to a specialized unit for BDI repair may improve long-term outcome.


Assuntos
Traumatismos Abdominais , Doenças dos Ductos Biliares , Colecistectomia Laparoscópica , Traumatismos Abdominais/cirurgia , Doenças dos Ductos Biliares/etiologia , Ductos Biliares/lesões , Ductos Biliares/cirurgia , Colecistectomia Laparoscópica/efeitos adversos , Humanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
20.
Comput Methods Biomech Biomed Engin ; 25(16): 1812-1820, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35152795

RESUMO

Titanium alloy-based Pedicle screw-rod fusion is a very common technique to provide higher fusion regularity than other methods. In recent times, Carbon-fibre-reinforced (CFR)-PEEK rod is used to better reduce the fusion rate. Alternatively, total disc replacement (TDR) is also very common for the non-fusion treatment method for degenerative disc disease (DDD). This study aims to investigate flexibility (ROM), stability, stress condition in implant, implant adjacent bone of the implanted lumbar spine during different physiological movements and loading environments. The finite element (FE) intact model of the lumbar spine (L2-L5) with two-level pedicle screw-rod fusion at L3-L4-L5 and two-level artificial disc replacement was developed. CFR-PEEK was taken for rod for semi-rigid fusion. UHMWPE was taken as core part of the artificial disc. The FE models were simulated under 6, 8 and 10 Nm moments in left right lateral bending, flexion and extension movements. The total ROM was reduced for two-level pedicle screw fixation and increased for the artificial disc replacement model during flexion extension compared to the intact spine. The total ROM was reduced by around 54% and 25% for two-level fixation and increased by 30% and 19.5% for artificial disc replacement spine, under flexion-extension and left-right lateral bending respectively. For screw fixation, the ROM increased by 15% and 18% reduced by 4.5% and 14% for disc replacement at the adjacent segments for flexion-extension and left-right lateral bending.


Assuntos
Disco Intervertebral , Parafusos Pediculares , Fusão Vertebral , Substituição Total de Disco , Análise de Elementos Finitos , Fusão Vertebral/métodos , Fenômenos Biomecânicos , Vértebras Lombares/cirurgia , Vértebras Lombares/fisiologia , Amplitude de Movimento Articular/fisiologia , Disco Intervertebral/cirurgia
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