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1.
Phys Rev Lett ; 132(13): 135101, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613280

RESUMO

We report observations of nonlinear two-plasmon decay instabilities (TPDIs) of a high-power microwave beam, a process similar to half-harmonic generation in optics, during electron cyclotron resonance heating in a tokamak. TPDIs are found to occur regularly in the plasma edge due to wave trapping in density fluctuations for various confinement modes, and the frequencies of both observed daughter waves agree with modeling. Emissions from a cascade of subsequent decays, which indicate a generation of ion Bernstein waves, are correlated with fast-ion generation. This emphasizes the limitations of standard linear microwave propagation models and possibly paves the way for novel microwave applications in plasmas.

2.
Environ Monit Assess ; 196(4): 365, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483634

RESUMO

Identifying factors contributing to water salinity is paramount in efficiently managing limited water resources in arid environments. The primary objective of this study is to enhance understanding regarding the hydrochemistry, source, and mechanism of water salinity, as well as to assess the suitability of water for various uses in southern Iraq. The groundwater samples were collected from water wells and springs and analyzed for major cations and anions along with stable isotopes (δ18O and δ2H) to accomplish the objective. The analysis of major ion chemistry, hydrochemical techniques, principal component analysis (PCA), and isotope signatures were adopted to determine the primary factors contributing to water mineralization. The study inferred that evaporation and geological processes encompassing water-rock interactions, such as dissolution precipitation and ion exchange, were key processes. The stable isotope analysis revealed that the water originated from meteoric sources and underwent significant evaporation during or before infiltration. The utility assessment of water samples indicates that most samples are not appropriate for consumption and are significantly below the established standards for potable water. In contrast, a significant portion of the groundwater samples were found to meet the criteria for irrigation suitability by adopting Wilcox and the US Salinity Laboratory criteria. The groundwater could be considered for irrigation with proper salinity control management. Overall, this study has significantly improved the understanding of the hydrogeochemical regimes and acts as a first step toward the sustainable utilization of water resources.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Salinidade , Iraque , Poluentes Químicos da Água/análise , Água Subterrânea/química , Água Potável/química , Isótopos/análise
3.
Biomed Eng Lett ; 14(2): 221-233, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374909

RESUMO

Lymph node metastasis detections are more clinically significant task associated with the presence and reappearance of lung cancer. The development of the computer-assisted diagnostic approach has greatly supported the diagnosis of human disorders in the field of medicine including lung cancer. Lung cancer treatment is possible if it is detected at the initial stage. Radiologists have great difficulty identifying and categorizing lung cancers in the initial phase. So, several methods were used to predict the lung cancer but does not provide accurate solutions with increased error rate. To overcome these issues, a Deep Volcanic Residual U-Net (DVR U-Net) for nodal metastasis is proposed in this manuscript which identifies the LC accurately in the early stage. Initially, the input images are taken from two datasets. After that, these input data are pre-processed using Anisotropic Diffusion Filter with a Fuzzy based Contrast-Limited Adaptive Histogram Equalization (ADFFCLAHE) method. Then the pre-processed images are given to the DVR U-Net to segment and extract the volume of interest for estimating the nodal stage of each volume of interest. Finally, DVR U-Net effectively detects and classifies the N + (nodal metastasis) or N- (non-nodal metastasis). The introduced method attains 99.9% higher accuracy as compared with the existing methods. Also, the statistical analysis of the Shapiro-Wilk test, Friedman test and Wilcoxon Signed-Rank test are executed to prove the statistical effectiveness of the implemented method.

4.
Chemosphere ; 340: 139898, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37607597

RESUMO

Groundwater is important for the survival of humanity and the demand for the same is drastically increasing globally. The precious water resources are under constant threat, either as a result of natural processes or due to the influence of the anthropogenic activities. Arsenic contamination of groundwater is one of those threats that have affected approximately over 500 million people in 107 countries globally. Although, many studies (∼1000 Nos.) have been carried out on arsenic hydrogeobiochemistry, only a few have reported, on the use of different isotopes in understanding the arsenic hydrochemistry, and its release mechanism and mobilization. Determination of the isotopic composition of a groundwater sample and its dissolved compounds enable a better insight into the hydrological processes that control the distribution and migration of arsenic in the subsurface hydrological system. The environmental isotopes of water molecules (δ18O and δ2H) have been widely used to assess the groundwater origin, its recharge mechanisms, the rock-water interactions and quality. The stable isotopes of dissolved compounds of water (δ34S, δ15N, δ13C, δ56Fe etc.) give better information on the reaction processes within these elements and thus act as a tracer for contaminants, while the radioactive isotopes, such as 14C, 3H, 81Kr, 36Cl, 39Ar etc., can be used to assess the residence time of groundwater and its renewability. This article reviews the different uses of environmental isotopes as tools for providing critical information on various hydrological processes in the arsenic contaminated regions that can't be obtained through conventional tools for better management of the groundwater resources.


Assuntos
Arsênio , Água Subterrânea , Humanos , Hidrologia , Isótopos , Água
5.
Environ Geochem Health ; 45(11): 7979-7997, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37515727

RESUMO

Nutrient management in resource conservation practices influence the structural and functional microbial diversities and thereby affect biological processes and biochemical properties in soil. We studied the long-term effects of resource conservation technologies on functional microbial diversity and their interactions with soil biochemical properties and enzymatic activities in tropical rice-green gram cropping system. The experiment includes seven treatments viz., conventional practice (CC), brown manuring (BM), green manuring (GM), wet direct drum sowing, zero tillage, green manuring-customized leaf colour chart based-N application (GM-CLCC-N) and biochar (BC) application. The result of the present study revealed that microbial biomass nitrogen (N), carbon (C) and phosphorus (P) in GM practice were increased by 23.3, 37.7 and 35.1%, respectively than CC. GM, BM and GM-CLCC-N treatments provide higher yields than conventional practice. The average well color development value, Shannon index and McIntosh index were significantly higher by 26.6%, 86.9% and 29.2% in GM as compared to control treatment. So, from this study we can conclude that resource conservation practices like GM, GM-CLCC N and BM in combination with chemical fertilizers provide easily decomposable carbon source to support the microbial growth. Moreover, dominance of microbial activity in biomass amended treatments (GM, GM-CLCC N and BM) indicated that these treatments could supply good amount of labile C sources on real time basis for microbial growth that may protect the stable C fraction in soil, hence could support higher yield and soil organic carbon build-up in long run under rice-green gram soil.


Assuntos
Oryza , Solo , Solo/química , Carbono/análise , Biomarcadores Ambientais , Indicadores de Qualidade em Assistência à Saúde , Agricultura/métodos , Fertilizantes , Nitrogênio/análise
6.
Soft comput ; : 1-11, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37362260

RESUMO

In the innovative concept of the "Social Internet of Things" (IoT), the IoT is combined with social platforms so that inanimate devices can form their interactions with one another. Still, customers have a wary attitude toward this new standard. They worry that their privacy will be invaded and their information will be made public. IoT won't become a frontrunner technology until we have tried true techniques to improve trustworthy connections between nodes. As a result, data privacy becomes extremely difficult, further increasing the difficulty of providing high-quality services and absolute safety. Several articles have attempted to analyze this issue. To categorize safe nodes in the IoT network, they suggested many models based on various attributes and aggregation techniques. In contrast, prior works failed to provide a means of identifying fraudulent nodes or distinguishing between different forms of assaults. To identify attacks carried out by hostile nodes and separate them from the network, we propose a novel Multi-hop Convolutional Neural Network with an attention mechanism (MH-CNN-AM). To achieve the best performance in the suggested research, performance measures including accuracy, precision, recall, F1-score, and MAE are studied and compared with the of existing methodologies.

7.
Crit Care Med ; 51(11): 1449-1460, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37294145

RESUMO

OBJECTIVE: To determine if initial fluid resuscitation with balanced crystalloid (e.g., multiple electrolytes solution [MES]) or 0.9% saline adversely affects kidney function in children with septic shock. DESIGN: Parallel-group, blinded multicenter trial. SETTING: PICUs of four tertiary care centers in India from 2017 to 2020. PATIENTS: Children up to 15 years of age with septic shock. METHODS: Children were randomized to receive fluid boluses of either MES (PlasmaLyte A) or 0.9% saline at the time of identification of shock. All children were managed as per standard protocols and monitored until discharge/death. The primary outcome was new and/or progressive acute kidney injury (AKI), at any time within the first 7 days of fluid resuscitation. Key secondary outcomes included hyperchloremia, any adverse event (AE), at 24, 48, and 72 hours, and all-cause ICU mortality. INTERVENTIONS: MES solution ( n = 351) versus 0.9% saline ( n = 357) for bolus fluid resuscitation during the first 7 days. MEASUREMENTS AND MAIN RESULTS: The median age was 5 years (interquartile range, 1.3-9); 302 (43%) were girls. The relative risk (RR) for meeting the criteria for new and/or progressive AKI was 0.62 (95% CI, 0.49-0.80; p < 0.001), favoring the MES (21%) versus the saline (33%) group. The proportions of children with hyperchloremia were lower in the MES versus the saline group at 24, 48, and 72 hours. There was no difference in the ICU mortality (33% in the MES vs 34% in the saline group). There was no difference with regard to infusion-related AEs such as fever, thrombophlebitis, or fluid overload between the groups. CONCLUSIONS: Among children presenting with septic shock, fluid resuscitation with MES (balanced crystalloid) as compared with 0.9% saline resulted in a significantly lower incidence of new and/or progressive AKI during the first 7 days of hospitalization.


Assuntos
Injúria Renal Aguda , Choque Séptico , Desequilíbrio Hidroeletrolítico , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Soluções Cristaloides , Hidratação/efeitos adversos , Hidratação/métodos , Ressuscitação/métodos , Solução Salina , Choque Séptico/terapia , Desequilíbrio Hidroeletrolítico/terapia , Lactente
8.
Chemphyschem ; 24(14): e202300098, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37221939

RESUMO

Dual ion batteries (DIBs) have garnered significant attention from researchers due to their unique ability to store charges using electrolyte-born ions, making them promising candidates for grid storage applications. However, despite extensive efforts to explore DIBs with various electrolytes, such as organic, aqueous, gel polymer etc., challenges such as electrolyte decomposition and poor stability of anode materials in aqueous electrolytes remain unresolved. To address these issues, we report a novel approach utilizing a flip-cum-reverse sequence of anion/cation storage chemistry in a ZnCl2 water-in-salt electrolyte (ZnCl2 -WiSE)-based reverse dual ion battery (RDIB), employing Zn-based Prussian blue analogue i. e., Zn3 [Fe(CN)6 ]2 and ferrocene-carbon composite (FcC) as cathode and anode electrodes, respectively. The RDIB operates in the opposite direction compared to conventional DIBs, offering a fresh perspective. Through our investigations, we discovered that increasing the concentration of ZnCl2 -WiSE [ZnCl2 -WiSE] resulted in a positive shift of 270 mV in the redox potential for cation/anion (de)insertion at the cathode, and a negative shift of 70 mV at the anode, indicating enhanced performance. Remarkably, the RDIB operate in 10 m ZnCl2 -WiSE exhibited an impressive energy density of 23 Wh kg-1 , showcasing the potential of this approach for high-performance energy storage.

9.
Crit Care Explor ; 5(1): e0815, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36600781

RESUMO

Our objective was to compare norepinephrine plus dobutamine versus epinephrine as the first-line agent in children with fluid refractory cold septic shock. DESIGN: Open-label randomized controlled study. SETTING: A single-center PICU from North India. PATIENTS: Children 2 months to less than 18 years old with fluid refractory cold septic shock. INTERVENTIONS: In the intervention group, norepinephrine and dobutamine were started and in the control group, epinephrine was started as the first-line vasoactive agent. The primary outcome was the proportion attaining shock resolution (attaining all the therapeutic endpoints) at 1 hour of therapy. MEASUREMENTS AND MAIN RESULTS: We enrolled 67 children: 34 in the norepinephrine plus dobutamine group (intervention) and 33 in the epinephrine group (control). There was no difference in shock resolution at 1 hour (17.6% vs 9%; risk ratio [RR], 2.0; 95% CI, 0.54-7.35; p = 0.25), 6 hours (76.4% vs 54.5%; RR, 1.69; 95% CI, 0.92-3.13; p = 0.06), and 24 hours between the intervention and control groups, respectively. Children in the norepinephrine plus dobutamine group attained shock resolution earlier (measured from starting of vasoactive agents to attaining all the therapeutic endpoints) (hazard ratio, 1.84 [1.1-3.08]). The difference in 28-day mortality was not significant (23.5% vs 39.3% in the intervention and control groups, respectively [RR, 0.59; 95% CI, 0.28-1.25]). CONCLUSIONS: In children with fluid refractory cold septic shock, with use of norepinephrine plus dobutamine as first-line agents, the difference in the proportion of children attaining shock resolution at 1 hour between the groups was inconclusive. However, the time to shock resolution was earlier in the norepinephrine plus dobutamine group. Also, fewer children in the intervention group were refractory to treatment. Further studies powered to detect (or exclude) an important difference would be required to test this intervention.

10.
J Environ Radioact ; 257: 107083, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36516518

RESUMO

Enrichment of heavy isotopes of hydrogen (D, 3H) and oxygen (18О) is observed in water samples collected from open brine storage of Kalush-Golinsky deposit. The brine storage facilities were formed during the operation of the Kalush-Golynsky deposit of potassium salts and after its decommissioning. Enrichment of isotopes is also observed in groundwater samples, collected from wells located along with downstream groundwater from brine storage facilities. The analysis of levels of influence of possible sources of chemical pollution of groundwater (waters of the Dombrovsky quarry, tailings and sludge storage, salt dumps, saline soils) and correlation relationships between isotopes and groundwater mineralization have been determined by statistical processing of geochemical data.


Assuntos
Água Subterrânea , Monitoramento de Radiação , Poluentes Químicos da Água , Sais/análise , Sais/química , Potássio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água Subterrânea/química , Isótopos de Oxigênio/análise
11.
Comput Intell Neurosci ; 2022: 3357508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211018

RESUMO

In the modern world, Tuberculosis (TB) is regarded as a serious health issue with a high rate of mortality. TB can be cured completely by early diagnosis. For achieving this, one tool utilized is CXR (Chest X-rays) which is used to screen active TB. An enhanced deep learning (DL) model is implemented for automatic Tuberculosis detection. This work undergoes the phases like preprocessing, segmentation, feature extraction, and optimized classification. Initially, the CXR image is preprocessed and segmented using AFCM (Adaptive Fuzzy C means) clustering. Then, feature extraction and several features are extracted. Finally, these features are given to the DL classifier Deep Belief Network (DBN). To improve the classification accuracy and to optimize the DBN, a metaheuristic optimization Adaptive Monarch butterfly optimization (AMBO) algorithm is used. Here, the Deep Belief Network with Adaptive Monarch butterfly optimization (DBN-AMBO) is used for enhancing the accuracy, reducing the error function, and optimizing weighting parameters. The overall implementation is carried out on the Python platform. The overall performance evaluations of the DBN-AMBO were carried out on MC and SC datasets and compared over the other approaches on the basis of certain metrics.


Assuntos
Aprendizado Profundo , Tuberculose , Algoritmos , Atenção à Saúde , Diagnóstico Precoce , Humanos , Tuberculose/diagnóstico por imagem
12.
Am J Audiol ; 31(4): 1098-1115, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35998292

RESUMO

OBJECTIVES: Adverse effects of noise exposure on hearing and cognition are well documented in the literature. Recently, it has becoming increasingly evident that noise exposure deteriorates suprathreshold auditory skills, even though the hearing sensitivity is intact. This condition is termed as cochlear synaptopathy or hidden hearing loss, which is apparent in animal models. However, equivocal findings are reported in humans. This study aimed at assessing the working memory, attention abilities, and suprathreshold hearing abilities in normal-hearing individuals with and without occupational noise exposure. We also explored the relationship between cognitive measures and suprathreshold auditory measures. DESIGN: The study participants were divided into two groups. All the participants had normal-hearing thresholds. The control group consisted of 25 individuals with no occupational noise exposure, whereas the noise exposure group had 25 individuals exposed to occupational noise of 85 dBA for a minimum period of 1 year. Working memory was assessed using auditory digit span (forward and backward), operation span, and reading span. The Erikson flanker test was used to evaluate attention abilities. The suprathreshold hearing was assessed in terms of gap detection thresholds and sentence identification in noise. RESULTS: The results showed that the noise exposure group performed poorly compared to the control group on all auditory and cognitive tasks except the reading span. CONCLUSION: The results of the study suggest that occupational noise exposure may hamper the cognitive skills and suprathreshold hearing abilities of the individual despite having normal peripheral hearing.


Assuntos
Ruído Ocupacional , Percepção da Fala , Animais , Humanos , Limiar Auditivo , Audição , Testes Auditivos , Ruído Ocupacional/efeitos adversos , Cognição
13.
Polymers (Basel) ; 13(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065404

RESUMO

Antimicrobial irradiated seaweed-neem biocomposite films were synthesized in this study. The storage functional properties of the films were investigated. Characterization of the prepared films was conducted using SEM, FT-IR, contact angle, and antimicrobial test. The macroscopic and microscopic including the analysis of the functional group and the gas chromatography-mass spectrometry test revealed the main active constituents present in the neem extract, which was used an essential component of the fabricated films. Neem leaves' extracts with 5% w/w concentration were incorporated into the matrix of seaweed biopolymer and the seaweed-neem bio-composite film were irradiated with different dosages of gamma radiation (0.5, 1, 1.5, and 2 kGy). The tensile, thermal, and the antimicrobial properties of the films were studied. The results revealed that the irradiated films exhibited improved functional properties compared to the control film at 1.5 kGy radiation dosage. The tensile strength, tensile modulus, and toughness exhibited by the films increased, while the elongation of the irradiated bio-composite film decreased compared to the control film. The morphology of the irradiated films demonstrated a smoother surface compared to the control and provided surface intermolecular interaction of the neem-seaweed matrix. The film indicated an optimum storage stability under ambient conditions and demonstrated no significant changes in the visual appearance. However, an increase in the moisture content was exhibited by the film, and the hydrophobic properties was retained until nine months of the storage period. The study of the films antimicrobial activities against Staphylococcus aureus (SA), and Bacillus subtilis (BS) indicated improved resistance to bacterial activities after the incorporation of neem leaves extract and gamma irradiation. The fabricated irradiated seaweed-neem bio-composite film could be used as an excellent sustainable packaging material due to its effective storage stability.

14.
Reumatismo ; 73(1): 24-31, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33874644

RESUMO

Genetic predisposition may play an important role in the development of fibromyalgia syndrome (FMS). Serotonin is known to be involved in pain modulation and serotonin-1A receptor plays a considerable role in determining the central 5-HT tone. Consequently, variation in 5-HT1A receptor gene (HTR1A) may be responsible for inter-individual variability in pain sensitivity and other clinical symptoms of FMS. Therefore, the objectives of this research work were to study the gene polymorphism of 5-HTR1A gene and to explore the correlation between rs6295 genotype (-1019C/G HTR1A) and duration of pain, pain intensity and pain related depression and anxiety, if any, in FMS. 5-HTR1A genotype for the C(-1019)G polymorphism was typed in 62 patients with FMS and 42 healthy subjects. Present pain intensity, components of pain and pain related depression and anxiety were assessed using the numerical pain rating scale, McGill pain questionnaire and Hamilton depression and anxiety rating scale respectively. 5-HTR1A gene was represented by three different genotypes, homozygous C/C, heterozygous C/G and homozygous G/G. Analysis of the 5-HTR1A gene showed a frequency of 58%, 31% and 11% for the C/C, C/G and G/G genotypes, respectively in FMS group. This proportion was 69%, 23% and 8% in healthy subjects. No significant correlation was observed between 5-HTR1A gene polymorphism and pain and related symptoms in FMS patients. To the best of our knowledge this is the first study which investigated the correlation between the 5-HTR1A gene polymorphism and pain intensity, the affective component of pain, pain related depression and anxiety in FMS.


Assuntos
Fibromialgia , Serotonina , Fibromialgia/genética , Genótipo , Humanos , Dor/genética , Polimorfismo de Nucleotídeo Único , Receptor 5-HT1A de Serotonina/genética
15.
Polymers (Basel) ; 12(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911705

RESUMO

Biopolymers have been used as a replacement material for synthetic polymers in scaffold forming due to its biocompatibility and nontoxic properties. Production of scaffold for tissue repair is a major part of tissue engineering. Tissue engineering techniques for scaffold forming with cellulose-based material is at the forefront of present-day research. Micro- and nanocellulose-based materials are at the forefront of scientific development in the areas of biomedical engineering. Cellulose in scaffold forming has attracted a lot of attention because of its availability and toxicity properties. The discovery of nanocellulose has further improved the usability of cellulose as a reinforcement in biopolymers intended for scaffold fabrication. Its unique physical, chemical, mechanical, and biological properties offer some important advantages over synthetic polymer materials. This review presents a critical overview of micro- and nanoscale cellulose-based materials used for scaffold preparation. It also analyses the relationship between the method of fabrication and properties of the fabricated scaffold. The review concludes with future potential research on cellulose micro- and nano-based scaffolds. The review provides an up-to-date summary of the status and future prospective applications of micro- and nanocellulose-based scaffolds for tissue engineering.

16.
Indian J Crit Care Med ; 24(7): 527-530, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32963434

RESUMO

BACKGROUND: Central venous catheterization is a vital procedure for volume resuscitation, infusion of drugs, and for central venous pressure monitoring in the perioperative period and intensive care unit (ICU). It is associated with position-related complications like arrhythmia's, thrombosis, tamponade, etc. Several methods are used to calculate the catheter insertion depth so as to prevent these position-related complications. OBJECTIVE: To compare Peres' formula and radiological landmark formula for central venous catheter insertion depth through right internal jugular vein (IJV) by the anterior approach. MATERIALS AND METHODS: A total of 102 patients posted for elective cardiac surgery were selected and divided into two equal groups-Peres' group (group P) and radiological landmark group (group R). Central venous catheterization of right IJV was done under ultrasound (USG) guidance. In group P, central venous catheter insertion depth was calculated as height (cm)/10. In group R, central venous catheter insertion depth was calculated by adding the distances from the puncture point to the right sternoclavicular joint and on chest X-ray the distance from the right sternoclavicular joint to carina. After insertion, the catheter tip position was confirmed using transesophageal echocardiography (TEE) in both the groups. RESULTS: About 49% of the catheters in group P and 74.5% in group R were positioned optimally as confirmed by TEE, which was statistically significant. No complications were observed in both the groups. CONCLUSION: Radiological landmark formula is superior to Peres' formula for measuring optimal depth of insertion of right internal jugular venous catheter. HOW TO CITE THIS ARTICLE: Manudeep AR, Manjula BP, Dinesh Kumar US. Comparison of Peres' Formula and Radiological Landmark Formula for Optimal Depth of Insertion of Right Internal Jugular Venous Catheters. Indian J Crit Care Med 2020; 24(7):527-530.

17.
Br Dent J ; 229(3): 148, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32811908
18.
Polymers (Basel) ; 12(5)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32422913

RESUMO

Neem leaves extract was incorporated into the matrix of seaweed biopolymer, and the seaweed-neem biocomposite films were irradiated with various doses of gamma irradiation (0.5, 1.5, 2.5, 3.5, and 4.5 kGy). The physical, barrier, antimicrobial, and mechanical properties of the films were studied. The incorporation of 5% w/w neem leaves extract into a seaweed-based film, and gamma irradiation dose of 2.5 kGy was most effective for improved properties of the film. The results showed that the interfacial interaction of the seaweed-neem improved with physical changes in colour and opacity. The water solubility, moisture content, and water vapour permeability and biodegradability rate of the film reduced. The contact angle values increased, which was interpreted as improved hydrophobicity. The tensile strength and modulus of the films increased, while the elongation of the composite films decreased compared to the control film. The film's antimicrobial activities against bacteria were improved. Thus, neem leaves extract in combination with the application of gamma irradiation enhanced the performance properties of the film that has potential as packaging material.

19.
J Colloid Interface Sci ; 568: 54-62, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32078938

RESUMO

Various experimental investigation had proved that metal dimers possess excellent oxygen reduction reaction (ORR) activity compared to single metal atom catalysts, due to the synergistic effect exerted by two metal atoms. However, it is still unclear how the electrocatalytic activity is enhanced in a fundamental aspect. In this study, we systematically investigated five 3d transition metals (Fe, Co, Ni, Cu and Zn) by density functional theory (DFT) to explore the ability of metal dimers to catalyze the ORR. It is found that different combinations of different metal atoms have different adsorption strengths to oxygenated intermediates, which helps to screen suitable catalyst materials. The scaling relationship of the free energy of adsorption of oxygen-containing species was calculated for various metal-dimer systems. The classical volcanic diagram is derived, and it is found that the CoZnOH embedded nitrogen-doped graphene (the overpotential is 0.61 V) shows the best catalytic properties, and it is predicted that when the adsorption free energy of OH is equal to 0.95 eV, the optimal overpotential is 0.29 V. Electronic structure calculations show that the pairing of different metal atoms alters the d-band center which in turn change the adsorption properties and hence ORR catalytic performance.

20.
Indian J Pediatr ; 86(12): 1142-1145, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31701427

RESUMO

The objective of the present study was to identify risk factors for mortality at admission in children admitted to the Pediatric Intensive Care Unit (PICU) with acute gastroenteritis (AGE) with severe dehydration and shock. This was a retrospective chart review of all cases of AGE with severe dehydration and shock admitted to the PICU from 2012 to 2017. Children who died during hospital stay were compared with those who survived. A total of 62 children were admitted with AGE to the PICU during this period. Twenty-four children (39%) died. The following variables were found to be significantly associated with death on univariate analysis: clinical pallor (p = 0.01), thrombocytopenia (p = 0.018), elevated leucocyte count (p = 0.02), hypoalbuminemia (p = 0.02) and severe acute malnutrition (SAM) (p = 0.04). On multivariate analysis, only hypoalbuminemia {RR [95% CI: 2.6 (1.27 to 9.21)]; 0.039} and SAM {RR [95% CI: 4.9 (1.12 to 10)]; 0.045} remained statistically significant. Children admitted with severe dehydration and shock had high mortality rates. These children were a sicker subset with probable sepsis. Severe acute malnutrition and hypoalbuminemia were associated with increased risk of death in these patients.


Assuntos
Criança Hospitalizada , Desidratação/complicações , Desidratação/mortalidade , Gastroenterite/complicações , Gastroenterite/mortalidade , Hospitalização , Adolescente , Criança , Pré-Escolar , Desidratação/fisiopatologia , Feminino , Gastroenterite/fisiopatologia , Humanos , Hipoalbuminemia/epidemiologia , Índia/epidemiologia , Lactente , Unidades de Terapia Intensiva Pediátrica , Tempo de Internação , Masculino , Desnutrição/epidemiologia , Mortalidade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Sepse , Choque , Trombocitopenia/epidemiologia
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