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1.
ACS Omega ; 9(13): 15202-15209, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38585125

RESUMO

In this study, surface-enhanced Raman spectroscopy (SERS) technique, along with principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA), is used as a simple, quick, and cost-effective analysis method for identifying biochemical changes occurring due to induced mutations in the Aspergillus niger fungus strain. The goal of this study is to identify the biochemical changes in the mutated fungal cells (cell mass) as compared to the control/nonmutated cells. Furthermore, multivariate data analysis tools, including PCA and PLS-DA, are used to further confirm the differentiating SERS spectral features among fungal samples. The mutations are caused in A. niger by the clustered regularly interspaced palindromic repeat CRISPR-Cas9 genomic editing method to improve their biotechnological potential for the production of cellulase enzyme. SERS was employed to detect the changes in the cells of mutated A. niger fungal strains, including one mutant producing low levels of an enzyme and another mutant producing high levels of the enzyme as a result of mutation as compared with an unmutated fungal strain as a control sample. The distinctive features of SERS corresponding to nucleic acids and proteins appear at 546, 622, 655, 738, 802, 835, 959, 1025, 1157, 1245, 1331, 1398, and 1469 cm-1. Furthermore, PLS-DA is used to confirm the 89% accuracy, 87.7% precision, 87% sensitivity, and 88.9% specificity of this method, and the value of the area under the curve (AUROC) is 0.67. It has been shown that surface-enhanced Raman spectroscopy is an effective method for identifying and differentiating biochemical changes in genome-modified fungal samples.

2.
Sci Total Environ ; 928: 172525, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631635

RESUMO

Bumblebees play a vital role in both natural and agricultural environments, but there has been a noticeable decline in their populations. Pesticides, particularly neonicotinoids, are widely regarded as a substantial contributing factor to the decline in bumblebee populations, as evidenced by the detrimental impacts documented across many stages of their life cycle. Mating is vital for the population maintenance of bumblebees. Nevertheless, there is a scarcity of research conducted on the effects of pesticides on the mating process. In this study, we individually examined the impact of imidacloprid on the mating behavior of bumblebee males and queens. A competitive mating experiment was conducted to evaluate the effect on the competitive prowess of male individuals and the mate selection behavior of female individuals. The study revealed that the mating rate of bumblebees exposed to a concentration of 10 ppb of imidacloprid was 3 %. This finding demonstrated a statistically significant impact when compared to the control group, which exhibited a mating rate of 58 % in the normal mating experiment. Furthermore, in the competitive mating experiment, we found that the competitive mating success rate of treated males (1 %) was significantly lower than that of untreated males (35 %). Hence, it provides evidence that neonicotinoid imidacloprid negatively affects bumblebee mating success and cautions us to protect bumblebees from pesticide exposure to prevent a severe impact on their populations.

3.
Mol Biol Rep ; 51(1): 490, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578476

RESUMO

BACKGROUND: One of the most challenging aspects of nucleic acid amplification tests is the extraction of genomic DNA. However, achieving satisfactory quality and quantity of genomic DNA is not always easy, while the demand for rapid, low-cost and less laborious DNA isolation methods is ever-increasing. METHODS AND RESULTS: We have developed a rapid (⁓2 min) crude DNA extraction method leading to direct-PCR that requires minimum reagents and laboratory equipment. It was developed by eliminating the time-consuming purification steps of DNA extraction, by processing the sample in optimized amounts of Taq KCl PCR buffer and DNARelease Additive/Proteinase K in only two minutes and carrying out amplification using conventional Taq DNA polymerase. The DNA preparation method was validated on muscle tissue samples from 12 different species as well as 48 cooked meat samples. Its compatibility was also successfully tested with different types of PCR amplification platforms extensively used for genetic analysis, such as simplex PCR, PCR-RFLP (Restriction Fragment Length Polymorphism), multiplex PCR, isothermal amplification, real-time PCR and DNA sequencing. CONCLUSIONS: The developed protocol provides sufficient amount of crude DNA from muscle tissues of different species for PCR amplifications to identify species-of-origin via different techniques coupled with PCR. The simplicity and robustness of this protocol make nucleic acid amplification assays more accessible and affordable to researchers and authorities for both laboratory and point-of-care tests.


Assuntos
DNA , Técnicas de Amplificação de Ácido Nucleico , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA/genética , Sequência de Bases , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase em Tempo Real , Músculos
4.
Sci Prog ; 107(2): 368504241242282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38614468

RESUMO

This research aims to optimize the silk and wool dyeing process using natural dyes from Bixa orellana (annatto) through response surface methodology. Central composite design experiments highlight the significant enhancement of color outcomes achieved through microwave treatment. For silk, the optimal conditions (80 °C for 40 min) with annatto extract yield a color strength (K/S) of 17.8588, while wool achieves a K/S of 7.5329. Introducing eco-friendly bio-mordants, such as pomegranate peel and red sumac tannins, enhances color strength. Pre-dyeing treatments with 2% red sumac, 1.5% pomegranate peel, and weld flower extracts for silk produce high color strength, with K/S values of 16.4063, 16.3784, and 12.1658, respectively. Post-dyeing, the K/S values increase to 40.1178, 17.4779, and 21.6494. Wool yarn exhibits similar improvements, with pre-dyeing K/S values of 13.1353, 13.5060, and 16.3232, escalating to 10.5892, 15.3141, and 23.4850 post-dyeing. Furthermore, this research underscores improved colorfastness properties, including notable enhancements in light, wash, and rubbing fastness for both silk fabric and wool yarn. These findings underscore the efficacy of the proposed sustainable dyeing methods, offering valuable insights for eco-friendly textile production.


Assuntos
Carotenoides , Árvores , , Animais , Bixaceae , Têxteis , Sementes , Seda
5.
Heliyon ; 10(8): e29175, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38628732

RESUMO

This study examined instructional practices and challenges English language teachers face in elementary schools. This study used a phenomenological approach and a mixed-method design. The data were collected through four tools: questionnaires, case studies, interviews, and observations in eight elementary schools in which eight educators and two hundred students participated from schools of three districts in central Punjab, Pakistan. This study aimed to explore the perspectives of teachers and students regarding the current pedagogical and instructional practices employed in English language classes. This study identified issues related to the lack of professional training and qualifications, overcrowded classrooms, cultural and social barriers, limited availability of the latest resources and technology, and a lack of parental cooperation. The findings suggested revisiting teachers' professional development programs, focusing on innovative teaching methods, incorporating technology into language teaching classes and classroom materials development, and adaptation preparation. It further suggested that teachers with low levels of professional qualifications and training should consider focusing on specific approaches to meet the challenges they face in language classes instead of general teaching approaches.

6.
Sci Total Environ ; 927: 172213, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580116

RESUMO

In the environment, sunlight or ultraviolet (UV) radiation is considered to be the primary cause of plastic aging, leading to their fragmentation into particles, including micro(nano)plastics (MNPs). Photoaged MNPs possess diverse interactive properties and ecotoxicological implications substantially different from those of pristine plastic particles. This review aims to highlight the mechanisms and implications of UV-induced photoaging of MNPs, with an emphasis on various UV sources and their interactions with co-occurring organic and inorganic chemicals, as well as the associated ecological and health impacts and factors affecting those interactions. Compared to UV-B, UV-A and UV-C were more widely used in laboratory studies for MNP degradation. Photoaged MNPs act as vectors for the transportation of organic pollutants, organic matter, and inorganic chemicals in the environment. Literature showed that photoaged MNPs exhibit a higher sorption capacity for PPCPs, PAHs, PBDEs, pesticides, humic acid, fulvic acid, heavy metals, and metallic nanoparticles than pristine MNPs, potentially causing significant changes in associated ecological and health impacts. Combined exposure to photoaged MNPs and organic and inorganic pollutants significantly altered mortality rate, decreased growth rate, histological alterations, neurological impairments, reproductive toxicity, induced oxidative stress, thyroid disruption, hepatotoxicity, and genotoxicity in vivo, both in aquatic and terrestrial organisms. Limited studies were reported in vitro and found decreased cellular growth and survival, induced oxidative stress, and compromised the permeability and integrity of the cell membrane. In addition, several environmental factors (temperature, organic matter, ionic strength, time, and pH), MNP properties (polymer types, sizes, surface area, shapes, colour, and concentration), and chemical properties (pollutant type, concentration, and physiochemical properties) can influence the photoaging of MNPs and associated impacts. Lastly, the research gaps and prospects of MNP photoaging and associated implications were also summarized. Future research should focus on the photoaging of MNPs under environmentally relevant conditions, exploiting the polydisperse characteristics of environmental plastics, to make this process more realistic for mitigating plastic pollution.


Assuntos
Poluentes Ambientais , Poluentes Ambientais/toxicidade , Raios Ultravioleta , Plásticos , Nanopartículas/toxicidade
7.
Heart Lung Circ ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604884

RESUMO

BACKGROUND: Heart transplantation is an effective treatment for end-stage congestive heart failure, however, achieving the right balance of immunosuppression to maintain graft function while minimising adverse effects is challenging. Serial endomyocardial biopsies (EMBs) are currently the standard for rejection surveillance, despite being invasive. Replacing EMB-based surveillance with cardiac magnetic resonance (CMR)-based surveillance for acute cardiac allograft rejection has shown feasibility. This study aimed to assess the cost-effectiveness of CMR-based surveillance in the first year after heart transplantation. METHOD: A prospective clinical trial was conducted with 40 orthotopic heart transplant (OHT) recipients. Participants were randomly allocated into two surveillance groups: EMB-based, and CMR-based. The trial included economic evaluations, comparing the frequency and cost of surveillance modalities in relation to quality-adjusted life years (QALYs) within the first year post-transplantation. Sensitivity analysis encompassed modelled data from observed EMB and CMR arms, integrating two hypothetical models of expedited CMR-based surveillance. RESULTS: In the CMR cohort, 238 CMR scans and 15 EMBs were conducted, versus (vs) 235 EMBs in the EMB group. CMR surveillance yielded comparable rejection rates (CMR 74 vs EMB 94 events, p=0.10) and did not increase hospitalisation risk (CMR 32 vs EMB 46 events, p=0.031). It significantly reduced the necessity for invasive EMBs by 94%, lowered costs by an average of AUD$32,878.61, and enhanced cumulative QALY by 0.588 compared with EMB. Sensitivity analysis showed that increased surveillance with expedited CMR Models 1 and 2 were more cost-effective than EMB (all p<0.01), with CMR Model 1 achieving the greatest cost savings (AUD$34,091.12±AUD$23,271.86 less) and utility increase (+0.62±1.49 QALYs, p=0.011), signifying an optimal cost-utility ratio. Model 2 showed comparable utility to the base CMR model (p=0.900) while offering the benefit of heightened surveillance frequency during periods of elevated rejection risk. CONCLUSIONS: CMR-based rejection surveillance in orthotopic heart transplant recipients provides a cost-effective alternative to EMB-based surveillance. Furthermore, it reduces the need for invasive procedures, without increased risk of rejection or hospitalisation for patients, and can be incorporated economically for expedited surveillance. These findings have important implications for improving patient care and optimising resource allocation in post-transplant management.

8.
Chemosphere ; 357: 141955, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38614403

RESUMO

A novel family of multifunctional nanomaterials called MXenes is quickly evolving, and it has potential applications that are comparable to those of graphene. This article provides a current explanation of the design and performance assessment of MXene-based membranes. The production of MXenes nanosheets are first described, with an emphasis on exfoliation, dispersion stability, and processability, which are essential elements for membrane construction. Further, critical discussion is also given to MXenes potential applications in Vacuum assisted filtration, casting method, Hot press method, electrospinning and electrochemical deposition and layer-by-layer assembly for the creation of MXene and MXene derived nanocomposite membranes. Additionally, the discussion is carried forward to give an insight to the modification methods for the construction of MXene-based membrane are described in the literature, including pure or intercalated nanomaterials, surface modifiers and miscellaneous two-dimensional nanomaterials. Furthermore, the review article highlights the potential utilization of MXene and MXene based membranes in separation and purification processes including removal of small organic molecules, heavy metals, oil-water separation and desalination. Finally, the perspective use of MXenes strong catalytic activity and electrical conductivity for specialized applications that are difficult for other nanomaterials to accomplish are discussed in conclusion and future prospectus section of the manuscript. Overall, important information is given to help the communities of materials science and membranes to better understand the potential of MXenes for creating cutting-edge separation and purification membranes.

9.
Heliyon ; 10(8): e29695, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660259

RESUMO

Cotton bollworm (Helicoverpa armigera) is a highly polyphagous, widely prevalent, and persistent Old World insect pest that affects numerous important crops that are directly consumed by people, including tomato, cotton, pigeon pea, chickpea, rice, sorghum, and cowpea. Insects do not synthesize steroids but obtain them from their diet. Inhibition of dietary uptake of steroids by insects is a potentially effective insecticidal mechanism that should not be toxic to humans and other mammals, who synthesize their steroids. Ten curcumin derivatives were tested against H. armigera sterol carrier protein-2 (HaSCP-2) for their potential as insecticidal agents. Curcumin derivatives were initially docked at the binding site of HaSCP-2 to determine their binding affinities and plausible binding modes. The binding modes predominantly show hydrophobic interactions of derivatives with Phe53, Phe110, and Phe89 as core interacting residues in the active site. Validation of in silico results was carried out by performing a fluorescence binding and displacement assay to determine the binding affinities of curcumin derivatives. Among a collection of curcumin derivatives tested, Cur10 showed the lowest IC50 value of 9.64 µM, while Cur07 was 19.86 µM, and Cur06 was 20.79 µM. There was a significant negative correlation between the ability of the curcumin derivatives tested to displace the fluorescent probe from the sterol binding site of HaSCP-2 and to inhibit Sf9 insect cell growth in culture, which is consistent with the curcumin derivatives acting by the novel mechanism of blocking sterol uptake. Then molecular dynamics simulation studies validated the predicted binding modes and the interactions of curcumin derivatives with HaSCP-2 protein. In conclusion, these studies support the potential use of curcumin derivatives as insecticidal agents.

10.
Heliyon ; 10(8): e29553, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660268

RESUMO

In the recent development of energy storage devices, the scientific study has demonstrated a significant interest in the applications of the magnesium iron oxide (MgFe2O4) nanoparticles. In this work, we present synthesized novel MgFe2O4 nanoparticles at different molarities (0.1-0.5 M), via hydrothermal technique. An X-ray Diffractometer was used to study the phase analysis of the prepared samples at different molarities. A pure cubic phase of the MgFe2O4 is observed at molar concentrations of 0.3 M and 0.4 M. However, the mixed phases consisting of (MgFe2O4 + Î³-Fe2O3) were also observed at 0.1 M, 0.2 M, and 0.5 M. The pure cubic MgFe2O4 nanoparticles depict the large value of crystallite size, 19.5 nm, and the lowest dislocation density and strain. The vibrating Sample Magnetometer shows the ferromagnetic nature of the pure MgFe2O4 with a high saturation magnetization. The value of saturation magnetization surged from 36.88 emu/g to 55.2 emu/g at 0.4 M concentration. The dielectric response of the materials as a function of applied frequency was studied thoroughly by using an Impedance Analyzer. The highest value of dielectric constant and low tangent loss was also reported at 0.4 M. Cole-Cole plots are the affirmation of the contribution of both grains and grain boundaries in the charge mechanism. These distinctive features make the synthesized material an excellent choice for future spintronics and energy storage devices.

11.
J Appl Stat ; 51(5): 913-934, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524795

RESUMO

Traditional process monitoring control charts (CCs) focused on sampling methods using fixed sampling intervals (FSIs). The variable sampling intervals (VSIs) scheme is receiving increasing attention, in which the sampling interval (SI) length varies according to the process monitoring statistics. A shorter SI is considered when the process quality indicates the possibility of an out-of-control (OOC) situation; otherwise, a longer SI is preferred. The VSI multivariate exponentially moving average for compositional data (VSI-MEWMACoDa) CC based on a coordinate representation using isometric log-ratio (ilr) transformation is proposed in this study. A methodology is proposed to obtain the optimal parameters by considering the zero-state (ZS) average time to signal (ZATS) and the steady-state (SS) average time to signal (SATS). The statistical performance of the proposed CC is evaluated based on a continuous-time Markov chain (CTMC) method for both cases, the ZS and the SS using a fixed value of in-control (IC) ATS0. Simulation results demonstrate that the VSI-MEWMACoDa CC has significantly decreased the OOC average time to signal (ATS) than the FSIMEWMACoDa CC. Moreover, it is found that the number of variables (d) has a negative impact on the ATS of the VSI-MEWMACoDa CC, and the subgroup size (n) has a mildly positive impact on the ATS of the VSI-MEWMACoDa CC. At the same time, the SATS of the VSI-MEWMACoDa CC is less than the ZATS of the VSI-MEWMACoDa CC for all the values of n and d. The proposed VSI-MEWMACoDa CC under steady-State performs effectively compared to its competitors, such as the FSI-MEWMACoDa CC, the VSI-T2CoDa CC and the FSI-T2CoDa CC. An example of an industrial problem from a plant in Europe is also given to study the statistical significance of the VSI-MEWMACoDa CC.

12.
Nucl Med Mol Imaging ; 58(2): 95-96, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38510826

RESUMO

The technetium-99m methylene diphosphonate (99mTc-MDP) whole-body bone scan along with single-photon emission computed tomography (SPECT/CT) can detect challenging soft tissue uptake patterns. We present a case of a 67-year-old female in whom the 99mTc-MDP scan, performed 3 hours after injection, revealed abnormal soft tissue uptake in the right thoracic region. No functioning right kidney was seen in the right lumbar region. Hybrid SPECT/CT revealed an ectopic right kidney in the subdiaphragmatic location, accompanied by gut loops and eventration of the right-sided diaphragm. This case underscores the value of SPECT/CT in identifying and characterizing unexpected anatomical abnormalities, such as ectopic kidneys.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124126, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490122

RESUMO

Large amount of sulphur is released by the combustion of fossil fuels in the form of SoX which affects human health and leads to acid rain. To overcome this issue, it is essential to eliminate sulphur moieties from heterocyclic organo-sulphur compounds like Dibenzothiophene (DBT) present in the petrol. In this study Surface enhanced Raman scattering (SERS) spectroscopy is used to analyze the desulfurizing activity of Tsukamurella paurometabola bacterial strain. The most prominent SERS peaks observed at 791, 837, 944 and 1032 cm-1, associated to C-S stretching, are solely observed in dibenzothiophene and its metabolite-I (DBTS) but absent in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Moreover, the SERS peaks observed at 974 (characteristic peak of benzene ring) and 1015 cm-1 is associated to C-C ring breathing while 1642 and 1655 cm-1 assigned to CC bonds of aromatic ring. These peaks are only observed in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Notably, these peaks are absent in the Dibenzothiophene and its metabolite-I which indicate that aromatic ring is carrying sulfur in this fraction. Moreover, multivariate data analytical tools like principal component analysis (PCA) and PCA-loadings are applied to further differentiate between dibenzothiophene and its metabolites that are Dibenzothiophene sulphone (metabolite-I) and 2-Hydroxybiphenyl (metabolite-II).


Assuntos
Actinobacteria , Compostos de Bifenilo , Análise Espectral Raman , Enxofre , Tiofenos , Humanos , Enxofre/química , Biodegradação Ambiental
14.
Materials (Basel) ; 17(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38541426

RESUMO

Solid-state refrigeration based on elastocaloric materials (eCMs) requires reversibility and repeatability. However, the intrinsic intergranular brittleness of ferromagnetic shape memory alloys (FMSMAs) limits fatigue life and, thus, is the crucial bottleneck for its industrial applications. Significant cyclic stability of elastocaloric effects (eCE) via 53% porosity in Ni-Fe-Ga FMSMA has already been proven. Here, Ni-Fe-Ga foams (single-/hierarchical pores) with high porosity of 64% and 73% via tailoring the material's architecture to optimize the eCE performances are studied. A completely reversible superelastic behavior at room temperature (297 K) is demonstrated in high porosity (64-73%) Ni-Fe-Ga foams with small stress hysteresis, which is greatly conducive to durable fatigue life. Consequentially, hierarchical pore foam with 64% porosity exhibits a maximum reversible ∆Tad of 2.0 K at much lower stress of 45 MPa with a large COPmat of 34. Moreover, it shows stable elastocaloric behavior (ΔTad = 2.0 K) over >300 superelastic cycles with no significant deterioration. The enhanced eCE cyclability can be attributed to the pore hierarchies, which remarkably reduce the grain boundary constraints and/or limit the propagation of cracks to induce multiple stress-induced martensitic transformations (MTs). Therefore, this work paves the way for designing durable fatigue life FMSMAs as promising eCMs by manipulating the material architectures.

15.
Sci Rep ; 14(1): 5986, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472251

RESUMO

Lead (Pb) is toxic to the development and growth of rice plants. Nanoparticles (NPs) have been considered one of the efficient remediation techniques to mitigate Pb stress in plants. Therefore, a study was carried out to examine the underlying mechanism of iron (Fe) and silicon (Si) nanoparticle-induced Pb toxicity alleviation in rice seedlings. Si-NPs (2.5 mM) and Fe-NPs (25 mg L-1) were applied alone and in combination to rice plants grown without (control; no Pb stress) and with (100 µM) Pb concentration. Our results revealed that Pb toxicity severely affected all rice growth-related traits, such as inhibited root fresh weight (42%), shoot length (24%), and chlorophyll b contents (26%). Moreover, a substantial amount of Pb was translocated to the above-ground parts of plants, which caused a disturbance in the antioxidative enzyme activities. However, the synergetic use of Fe- and Si-NPs reduced the Pb contents in the upper part of plants by 27%. It reduced the lethal impact of Pb on roots and shoots growth parameters by increasing shoot length (40%), shoot fresh weight (48%), and roots fresh weight (31%). Both Si and Fe-NPs synergistic application significantly elevated superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione (GSH) concentrations by 114%, 186%, 135%, and 151%, respectively, compared to plants subjected to Pb stress alone. The toxicity of Pb resulted in several cellular abnormalities and altered the expression levels of metal transporters and antioxidant genes. We conclude that the synergistic application of Si and Fe-NPs can be deemed favorable, environmentally promising, and cost-effective for reducing Pb deadliness in rice crops and reclaiming Pb-polluted soils.


Assuntos
Nanopartículas , Oryza , Poluentes do Solo , Oryza/genética , Silício/farmacologia , Chumbo/metabolismo , Ferro/metabolismo , Antioxidantes/metabolismo , Glutationa/metabolismo , Superóxido Dismutase/metabolismo , Estresse Oxidativo , Poluentes do Solo/metabolismo
16.
J Environ Manage ; 356: 120579, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503230

RESUMO

In contemporary times, geopolitical risk, and natural resources prices are susceptible due to the Russian-Ukraine conflict. In the meantime, emerging economies are struggling to explore the factors that could reduce ecological challenges and enhance environmental management. This research aims to analyze several economic, environmental, political, and institutional variables to ascertain their influence on greenhouse gas emissions in China. Covering the latest period from 1990 to 2022, various time series tests, including normality, stationarity, and cointegration tests. The results confirm that the variables studied have a stable pattern over time and are connected in the long run. The non-normal distribution of variables leads to opt novel moment quantile regression, where the results are tested for robustness via parametric approaches. The empirical results asserted that economic growth, natural resource prices, and trade significantly enhance ecological challenges (emissions). However, globalization, geopolitical risk, and institutional quality significantly reduce such environmental challenges. The results are robust, and both unidirectional and bidirectional causal associations confirm the importance of these variables in environmental management. Based on the results, this study recommends engagement in environmentally-friendly trading, investment in clean and green energy, and strengthening institutional quality for the region's environmental recovery.


Assuntos
Dióxido de Carbono , Conservação dos Recursos Naturais , Ucrânia , Dióxido de Carbono/análise , Desenvolvimento Econômico , China , Federação Russa , Energia Renovável
17.
Artigo em Inglês | MEDLINE | ID: mdl-38478445

RESUMO

In a previous paper, we have shown that a recurrent neural network (RNN) can be used to detect cellular network radio signal degradations accurately. We unexpectedly found, though, that accuracy gains diminished as we added layers to the RNN. To investigate this, in this article, we build a parallel model to illuminate and understand the internal operation of neural networks (NNs), such as the RNN, which store their internal state to process sequential inputs. This model is widely applicable in that it can be used with any input domain where the inputs can be represented by a Gaussian mixture. By looking at RNN processing from a probability density function (pdf) perspective, we are able to show how each layer of the RNN transforms the input distributions to increase detection accuracy. At the same time we also discover a side effect acting to limit the improvement in accuracy. To demonstrate the fidelity of the model, we validate it against each stage of RNN processing and output predictions. As a result, we have been able to explain the reasons for RNN performance limits with useful insights for future designs for RNNs and similar types of NN.

19.
RSC Adv ; 14(12): 8548-8555, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38482068

RESUMO

The ability of surface-enhanced Raman spectroscopy (SERS) to generate spectroscopic fingerprints has made it an emerging tool for biomedical applications. The objective of this study is to confirm the potential use of Raman spectroscopy for early disease diagnosis based on blood serum. In this study, a total of sixty blood serum samples, consisting of forty from diseased patients and twenty (controls) from healthy individuals, was used. Because disease biomarkers, found in the lower molecular weight fraction, are suppressed by higher molecular weight proteins, 50 kDa Amicon ultrafiltration centrifugation devices were used to produce two fractions from whole blood serum consisting of a filtrate, which is a low molecular weight fraction, and a residue, which is a high molecular weight fraction. These fractions were then analyzed, and their SERS spectral data were compared with those of healthy fractions. The SERS technique was utilized on blood serum, filtrate and residue of patients with tuberculosis to identify characteristic SERS spectral features associated with the development of disease, which can be used to differentiate them from healthy samples using silver nanoparticles as a SERS substrate. For further analysis, the effective chemometric technique of principal component analysis (PCA) was used to qualitatively differentiate all the analyzed samples based on their SERS spectral features. Partial least squares discriminant analysis (PLS-DA) accurately classified the filtrate portions of healthy and tuberculosis samples with 97% accuracy, 97% specificity, 98% sensitivity, and an area under the receiver operating characteristic (AUROC) curve of 0.74.

20.
Molecules ; 29(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474656

RESUMO

The SARS-CoV-2 virus and its mutations have affected human health globally and created significant danger for the health of people all around the world. To cure this virus, the human Angiotensin Converting Enzyme-2 (ACE2) receptor, the SARS-CoV-2 main protease (Mpro), and spike proteins were found to be likely candidates for the synthesis of novel therapeutic drug. In the past, proteins were capable of engaging in interaction with a wide variety of ligands, including both manmade and plant-derived small molecules. Pyrus communis L., Ginko bibola, Carica papaya, Syrian rue, and Pimenta dioica were some of the plant species that were studied for their tendency to interact with SARS-CoV-2 main protease (Mpro) in this research project (6LU7). This scenario investigates the geometry, electronic, and thermodynamic properties computationally. Assessing the intermolecular forces of phytochemicals with the targets of the SARS-CoV-2 Mpro spike protein (SP) resulted in the recognition of a compound, kaempferol, as the most potent binding ligand, -7.7 kcal mol-1. Kaempferol interacted with ASP-187, CYS-145, SER-144, LEU 141, MET-165, and GLU-166 residues. Through additional molecular dynamic simulations, the stability of ligand-protein interactions was assessed for 100 ns. GLU-166 remained intact with 33% contact strength with phenolic OH group. We noted a change in torsional conformation, and the molecular dynamics simulation showed a potential variation in the range from 3.36 to 7.44 against a 45-50-degree angle rotation. SAR, pharmacokinetics, and drug-likeness characteristic investigations showed that kaempferol may be the suitable candidate to serve as a model for designing and developing new anti-COVID-19 medicines.


Assuntos
COVID-19 , Proteases 3C de Coronavírus , Humanos , Animais , Cricetinae , Simulação de Acoplamento Molecular , Quempferóis , Ligantes , Simulação de Dinâmica Molecular , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Mesocricetus , Inibidores de Proteases
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