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1.
Nature ; 576(7785): 85-90, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31723266

RESUMO

Thermoelectric materials transform a thermal gradient into electricity. The efficiency of this process relies on three material-dependent parameters: the Seebeck coefficient, the electrical resistivity and the thermal conductivity, summarized in the thermoelectric figure of merit. A large figure of merit is beneficial for potential applications such as thermoelectric generators. Here we report the thermal and electronic properties of thin-film Heusler alloys based on Fe2V0.8W0.2Al prepared by magnetron sputtering. Density functional theory calculations suggest that the thin films are metastable states, and measurements of the power factor-the ratio of the Seebeck coefficient squared divided by the electrical resistivity-suggest a high intrinsic figure of merit for these thin films. This may arise from a large differential density of states at the Fermi level and a Weyl-like electron dispersion close to the Fermi level, which indicates a high mobility of charge carriers owing to linear crossing in the electronic bands.

2.
BMC Plant Biol ; 24(1): 502, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840053

RESUMO

BACKGROUND: Lentil is a significant legume that are consumed as a staple food and have a significant economic impact around the world. The purpose of the present research on lentil was to assess the hydrothermal time model's capacity to explain the dynamics of Lens culinaris L. var. Markaz-09 seed germination, as well as to ascertain the germination responses at various sub-optimal temperatures (T) and water potentials (Ψ). In order to study lentil seed germination (SG) behavior at variable water potentials (Ψs) and temperatures (Ts). A lab experiment employing the hydrothermal time model was created. Seeds were germinated at six distinct temperatures: 15 0С, 20 0С, 25 0С, 30 0С, 35 0С, and 40 0С, with five Ψs of 0, -0.3, -0.6, -0.9, and - 1.2 MPa in a PEG-6000 (Polyethylene glycol 6000) solution. RESULTS: The results indicated that the agronomic parameters like Germination index (GI), Germination energy (GE), Timson germination index (TGI), were maximum in 25 0C at (-0.9 MPa) and lowest at 40 0C in 0 MPa. On other hand, mean germination time (MGT) value was highest at 15 0C in -1.2 MPa and minimum at 40 0C in (-0.6 MPa) while Mean germination rate (MGR) was maximum at 40 0C in (0 MPa) and minimum at 15 0C in (-0.6 MPa). CONCLUSIONS: The HTT model eventually defined the germination response of Lens culinaris L. var. Markaz-09 (Lentil) for all Ts and Ψs, allowing it to be employed as a predictive tool in Lens culinaris L. var. Markaz-09 (Lentil) seed germination simulation models.


Assuntos
Germinação , Lens (Planta) , Sementes , Temperatura , Germinação/fisiologia , Sementes/fisiologia , Sementes/crescimento & desenvolvimento , Lens (Planta)/fisiologia , Lens (Planta)/crescimento & desenvolvimento , Água/metabolismo , Modelos Biológicos , Pressão Osmótica
3.
BMC Plant Biol ; 24(1): 108, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347449

RESUMO

Soil pollution with heavy metals has grown to be a big hassle, leading to the loss in farming production particularly in developing countries like Pakistan, where no proper channel is present for irrigation and extraction of these toxic heavy metals. The present study aims to ameliorate the damages caused by heavy metal ions (Hg-Mercury) on rapeseed (Brassica napus L.) via a growth regulator (α-tocopherol 150 mg/L) and thermopriming technique at 4 °C and 50 °C to maintain plant agronomical and physiological characteristics. In pot experiments, we designed total of 11 treatments viz.( T0 (control), T1 (Hg4ppm), T2 (Hg8ppm), T3 (Hg4ppm + 4 °C), T4 (Hg4ppm + 4 °C + tocopherol (150 m/L)), T5 (Hg4ppm + 50 °C), T6 (Hg4ppm + 50 °C + tocopherol (150 mg/L)), T7 (Hg8ppm + 4 °C), T8 (Hg8ppm + 4 °C + tocopherol (150 mg/L)), T9 (Hg8ppm + 50 °C), T10 (Hg8ppm + 50 °C + tocopherol (150 mg/L) the results revealed that chlorophyll content at p < 0.05 with growth regulator and antioxidant enzymes such as catalase, peroxidase, and malondialdehyde enhanced up to the maximum level at T5 = Hg4ppm + 50 °C (50 °C thermopriming under 4 ppm mercuric chloride stress), suggesting that high temperature initiate the antioxidant system to reduce photosystem damage. However, protein, proline, superoxide dismutase at p < 0.05, and carotenoid, soluble sugar, and ascorbate peroxidase were increased non-significantly (p > 0.05) 50 °C thermopriming under 8 ppm high mercuric chloride stress (T9 = Hg8ppm + 50 °C) representing the tolerance of selected specie by synthesizing osmolytes to resist oxidation mechanism. Furthermore, reduction in % MC (moisture content) is easily improved with foliar application of α-tocopherol and 50 °C thermopriming and 4 ppm heavy metal stress at T6 = Hg4ppm + 50 °C + α-tocopherol (150 mg/L), with a remarkable increase in plant vigor and germination energy. It has resulted that the inhibitory effect of only lower concentration (4 ppm) of heavy metal stress was ameliorated by exogenous application of α-tocopherol and thermopriming technique by synthesizing high levels of proline and antioxidant activities in maintaining seedling growth and development on heavy metal contaminated soil.


Assuntos
Brassica napus , Metais Pesados , Poluentes do Solo , Antioxidantes/metabolismo , alfa-Tocoferol/farmacologia , alfa-Tocoferol/metabolismo , Brassica napus/metabolismo , Cloreto de Mercúrio/toxicidade , Cloreto de Mercúrio/metabolismo , Tocoferóis/metabolismo , Tocoferóis/farmacologia , Metais Pesados/metabolismo , Prolina/metabolismo , Poluentes do Solo/metabolismo
4.
BMC Plant Biol ; 24(1): 477, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816803

RESUMO

BACKGROUND: The rate of germination and other physiological characteristics of seeds that are germinating are impacted by deep sowing. Based on the results of earlier studies, conclusions were drawn that deep sowing altered the physio-biochemical and agronomic characteristics of wheat (Triticum aestivum L.). RESULTS: In this study, seeds of wheat were sown at 2 (control) and 6 cm depth and the impact of exogenously applied salicylic acid and tocopherol (Vitamin-E) on its physio-biochemical and agronomic features was assessed. As a result, seeds grown at 2 cm depth witnessed an increase in mean germination time, germination percentage, germination rate index, germination energy, and seed vigor index. In contrast, 6 cm deep sowing resulted in negatively affecting all the aforementioned agronomic characteristics. In addition, deep planting led to a rise in MDA, glutathione reductase, and antioxidants enzymes including APX, POD, and SOD concentration. Moreover, the concentration of chlorophyll a, b, carotenoids, proline, protein, sugar, hydrogen peroxide, and agronomic attributes was boosted significantly with exogenously applied salicylic acid and tocopherol under deep sowing stress. CONCLUSIONS: The results of the study showed that the depth of seed sowing has an impact on agronomic and physio-biochemical characteristics and that the negative effects of deep sowing stress can be reduced by applying salicylic acid and tocopherol to the leaves.


Assuntos
Germinação , Ácido Salicílico , Tocoferóis , Triticum , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Triticum/efeitos dos fármacos , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Tocoferóis/metabolismo , Germinação/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Antioxidantes/metabolismo , Estresse Fisiológico , Desenvolvimento Sustentável , Clorofila/metabolismo
5.
Pharmacol Res ; 200: 107076, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237646

RESUMO

Sciatica characterized by irritation, inflammation, and compression of the lower back nerve, is considered one of the most common back ailments globally. Currently, the therapeutic regimens for sciatica are experiencing a paradigm shift from the conventional pharmacological approach toward exploring potent phytochemicals from medicinal plants. There is a dire need to identify novel phytochemicals with anti-neuropathic potential. This review aimed to identify the potent phytochemicals from diverse medicinal plants capable of alleviating neuropathic pain associated with sciatica. This review describes the pathophysiology of sciatic nerve pain, its cellular mechanisms, and the pharmacological potential of various plants and phytochemicals using animal-based models of sciatic nerve injury-induced pain. Extensive searches across databases such as Medline, PubMed, Web of Science, Scopus, ScienceDirect, and Google Scholar were conducted. The findings highlights 39 families including Lamiaceae, Asteraceae, Fabaceae, and Apocyanaceae and Cucurbitaceae, effectively treating sciatic nerve injury-induced pain. Flavonoids made up 53% constituents, phenols and terpenoids made up 15%, alkaloids made up 13%, and glycosides made up 6% to be used in neuorpathic pain. Phytochemicals derived from various medicinal plants can serve as potential therapeutic targets for both acute and chronic sciatic injury-induced neuropathic pain.


Assuntos
Neuralgia , Plantas Medicinais , Neuropatia Ciática , Ciática , Animais , Humanos , Plantas Medicinais/química , Ciática/tratamento farmacológico , Ciática/etiologia , Neuralgia/tratamento farmacológico , Neuralgia/etiologia , Neuropatia Ciática/tratamento farmacológico , Inflamação/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/química , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química
6.
Fish Shellfish Immunol ; 152: 109792, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39084277

RESUMO

The aim of this study was to investigate the effects of antibacterial peptides from Brevibacillus texasporus (BT) on the growth performance, meat quality and gut health of cultured largemouth bass (Micropterus salmoides). Largemouth bass (36.17 ± 1.52 g) were divided into 2 groups and each group was fed with diets supplemented with or without 200 ppm of BT peptides for 130 days. The results showed that BT peptides had no significant influences on growth performance and body indexes, but significantly enhanced total antioxidant capacity and lysozyme content in the serum. Moreover, digestive enzymes activities and intestinal villous height were also prominently increased. From meat quality aspect, no significant differences were found in nutritional components, amino acid composition, fatty acid composition and texture property, except the values of hardness, gumminess and γ-linolenic acid (C18:3n6) were remarkably increased after BT peptides intervention. Finally, the results of gut microbiota and short chain fatty acids revealed that BT peptides significantly decreased the relative abundances of harmful bacteria such as genus Acinetobacter and Pseudomonas, and increased the production of short chain fatty acids. In conclusion, this study confirmed that BT peptides could be used to improve the health of largemouth bass, which provided novel insights into the application of antimicrobial peptides in aquacultures.


Assuntos
Ração Animal , Bass , Brevibacillus , Dieta , Microbioma Gastrointestinal , Animais , Bass/crescimento & desenvolvimento , Ração Animal/análise , Dieta/veterinária , Microbioma Gastrointestinal/efeitos dos fármacos , Carne/análise , Suplementos Nutricionais/análise , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Distribuição Aleatória , Proteínas de Bactérias
7.
J Fluoresc ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967859

RESUMO

Nitrite ions (NO2-), as one of the leading type-A inorganic-anion, showing significant-effects in the aquatic environment and also to humans health. Whereas, the higher uptake causes detrimental threat to human health leading to various chronic diseases, thus demanding efficient, reliable and convenient method for its monitoring. For this purpose, in the present research study we have fabricated the mimetic nonozyme like catalyst based colorimetric nitrite sensor. The acetic acid capped Zinc Oxide (ZnO) nanosheets (NSs) were introduce as per-oxidase mimetic like catalyst which shows high efficiency towards the oxidative catalysis of colorless tetramethylbenzidine (TMB) to oxidized-TMB (blue color) in the presence of Hydrogen-peroxide (H2O2). The present nitrite ions will stimulate the as formed oxidized-TMB (TMBox), and will caused diazotization reaction (diazotized-TMBox), which will not only decreases the peak intensity of UV-visible peak of TMBox at 652 nm but will also produces another peak at 446 nm called as diazotized-TMBox peak, proving the catalytic reaction between the nitrite ions and TMBox. Further, the prepared colorimetric sensor exhibits better sensitivity with a wider range of concentration (1 × 10-3-4.50 × 10-1 µM), lowest limit of detection (LOD) of 0.22 ± 0.05 nM and small limit of quantification (LOQ) 0.78 ± 0.05 nM having R2 value of 0.998. Further, the colorimetric sensor also manifest strong selectivity towards NO2- as compared to other interference in drinking water system. Resultantly, the prepared sensor with outstanding repeatability, stability, reproducibility, re-usability and its practicability in real water samples also exploit its diverse applications in food safety supervision and environmental monitoring.

8.
Eur J Clin Pharmacol ; 80(9): 1271-1283, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38722350

RESUMO

PURPOSE: Currently, body weight-based dosing of rifampicin is recommended. But lately, fat-free mass (FFM) was reported to be superior to body weight (BW). The present evaluation aimed to assess the influence of body mass-related covariates on rifampicin's pharmacokinetics (PK) parameters in more detail using non-linear mixed effects modeling (NLMEM). METHODS: Twenty-four healthy Caucasian volunteers were enrolled in a bioequivalence study, each receiving a test and a reference tablet of 600 mg of rifampicin separated by a wash-out period of at least 9 days. Monolix version 2023R1 was used for NLMEM. Monte Carlo simulations (MCS) were performed to visualize the relationship of body size descriptors to the exposure to rifampicin. RESULTS: A one-compartment model with nonlinear (Michaelis-Menten) elimination and zero-order absorption kinetics with a lag time best described the data. The covariate model including fat-free mass (FFM) on volume of distribution (V/F) and on maximum elimination rate (Vmax/F) lowered the objective function value (OFV) by 56.4. The second-best covariate model of sex on V/F and Vmax/F and BW on V/F reduced the OFV by 51.2. The decrease in unexplained inter-individual variability on Vmax/F in both covariate models was similar. For a given dose, MCS showed lower exposure to rifampicin with higher FFM and accordingly in males compared to females with the same BW and body height. CONCLUSION: Our results indicate that beyond BW, body composition as reflected by FFM could also be relevant for optimized dosing of rifampicin. This assumption needs to be studied further in patients treated with rifampicin.


Assuntos
Voluntários Saudáveis , Modelos Biológicos , Rifampina , População Branca , Humanos , Rifampina/farmacocinética , Rifampina/administração & dosagem , Masculino , Feminino , Adulto , Adulto Jovem , Equivalência Terapêutica , Método de Monte Carlo , Antibióticos Antituberculose/farmacocinética , Antibióticos Antituberculose/administração & dosagem , Peso Corporal , Estudos Cross-Over , Dinâmica não Linear
9.
Environ Res ; 252(Pt 4): 119069, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38735376

RESUMO

Dwarf bamboo (Indocalamus decorus) is an O3-tolerant plant species. To identify the possible mechanism and response of leaf morphological, antioxidant, and anatomical characteristics to elevated atmospheric O3 (EO3) concentrations, we exposed three-year-old I. decorus seedlings to three O3 levels (low O3-LO: ambient air; medium O3-MO: Ambient air+70 ppb high O3-HO: Ambient air+140 ppb O3) over a growing season using open-top chambers. Leaf shape and stomatal characteristics, and leaf microscopic structure of I. decorus were examined. The results indicated that 1) the stomata O3 flux (Fst) of HO decreased more rapidly under EO3 as the exposure time increased. The foliar O3 injury of HO and MO occurred when AOT40 was 26.62 ppm h and 33.20 ppm h, respectively, 2) under EO3, leaf number, leaf mass per area, leaf area, and stomata length/width all decreased, while leaf thickness, stomatal density, width, and area increased compared to the control, 3) MDA and total soluble protein contents all showed significantly increase under HO (36.57% and 32.77%) and MO(31.91% and 19.52%) while proline contents only increased under HO(33.27%). 4) MO and HO increased bulliform cells numbers in the leaves by 6.28% and 23.01%, respectively. HO reduced the transverse area of bulliform cells by 13.73%, while MO treatments had no effect, and 5) the number of fusoid cells interspace, the transverse area of fusoid cells interspace, and mesophyll thickness of HO significantly increased by 11.16%, 28.58%, and 13.42%, respectively. In conclusion, I. decorus exhibits strong O3 tolerance characteristics, which stem from adaptions in the leaf's morphological, structural, antioxidant, and anatomical features. One critical attribute was the enlargement of the bulliform cell transverse area and the transverse area of fusoid cells interspace that drove this resistance to O3. Local bamboo species with high resistance to O3 pollution thus need to be promoted for sustained productivity and ecosystem services in areas with high O3 pollution.


Assuntos
Poluentes Atmosféricos , Ozônio , Folhas de Planta , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Ozônio/toxicidade , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Poaceae/efeitos dos fármacos , Poaceae/anatomia & histologia , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/anatomia & histologia
10.
Spinal Cord ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060481

RESUMO

CONTEXT/OBJECTIVE: People with spinal cord injury (SCI) are the deciding force behind the rehabilitation program to improve their quality of life (QoL) based on their personal preferences. Here we aimed to determine the preferences perceived most vital by Saudi SCI population to improve their QoL, and explore if these preferences are affected by gender, education, and duration, level, or extent of injury. DESIGN: Participants ranked seven priorities of bodily functions as Rank I-VII with "I" being "Most important," and "VII" being "Least important." SETTING: Inpatient rehabilitation facility. PARTICIPANTS: 120 participants (>18 years of age) of either sex with SCI without polytrauma, acquired brain injury, neurodegenerative disease, and dementia. OUTCOME MEASURES: Ranking scale of seven priorities of bodily functions as Rank I-VII with "I" being "Most important," and "VII" being "Least important." RESULTS: Of 101 individuals (mean age: 35.2 ± 14.8 years) finally included, 70.3% were males, 66.3% had onset of SCI since ≥ 3 years, 48.5% had a complete injury, and 75% had paraplegia. Most (26.7%) participants ranked walking as the first priority followed by hand/arm function (20.8%). Sexual function was the least important priority (39.6%). Hand/arm function was significantly more important for individuals with tetraplegia (p < 0.001). Trunk strength and balance was significantly less important for individuals with complete injury (p = 0.037). Participants with the onset of injury < 3 years and a complete injury reported bladder/bowel function as significantly more important (p = 0.011). Walking was significantly more important for people with incomplete injury and for people with injury duration ≥ 3 years (p = 0.022, p = 0.002 respectively). CONCLUSION: The top priority in our sample of Saudi people with SCI was walking followed by hand/arm function while the least desired function was regaining sexual function. Walking was a prioritized function for people with injury duration ≥ 3 years and people with a complete injury while hand/arm function was highly prioritized by people with tetraplegia.

11.
Biomed Chromatogr ; : e5968, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039695

RESUMO

Withania somnifera belongs to the family Solanaceae, commonly called ashwagandha, and is traditionally used as an astringent, hepatoprotective and antioxidant, and as a treatment for rheumatism. Therefore the current study aimed to explore the dichloromethane fraction of W. somnifera whole plant (DCFWS) and ethyl acetate fraction of W. somnifera (EAFWS) using gas chromatoghraphy-mass spectrometry (GC-MS) analysis and to find the acetylcholinesterase inhibition potential along with spasmolytic activity. The GC-MS-detected phytochemicals were 2,4-bis(1,1-dimethylethyl), hexadecanoic acid, 1-nonadecene and 11-octadecenoic acid. The DCFWS and EAFWS exhibited acetylcholinesterase inhibitory potential with significant inhibitory concentration values. The acute toxicity results of both fractions showed high toxicity, causing emesis at 0.5 g and both emesis and diarrhea at 1 g/kg. Both fractions exhibited significant (p ≤ 0.01) laxative activity against metronidazole (7 mg/kg) and loperamide hydrochloride (4 mg/kg) induced constipation. Both DCFWS (66.8 ± 3.85%) and EAFWS (58.58 ± 3.28%) significantly (p ≤ 0.05) increased charcoal movement compared with distal water (43.93 ± 4.34%). Similarly the effect of DCFWS on KCl-induced (80 mm) contraction was more significant as compared with EAFWS. It was concluded that the plant can be used in the treatment of gastrointestinal tract diseases such as constipation. Furthermore, additional work is required in the future to determine the bioactive compounds that act as therapeutic agents in W. somnifera.

12.
Chem Biodivers ; : e202401013, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189631

RESUMO

The present paper is a comprehensive study on the optimization of ultrasonic assisted extraction and characterization of valued components from the newly developed garlic cultivar NARC-G1. The response surface methodology was employed to optimize the extraction time, solvent-to-solid ratio and extraction temperature, for optimal total phenolic contents (TPC), DPPH radical scavenging activity, α-amylase inhibition, and α-glucosidase inhibition. Under the optimized conditions (23 min extraction time, 60 °C temperature, and 39 : 1 solvent-to-solute ratio) the optimal TPC (13.76 mg GAE/g), DPPH radical scavenging activity (62.76 %), α-amylase inhibition (71.43 %), and α-glucosidase inhibition (79.43 %) were obtained. Significant correlations were observed between actual values and predicted values for the selected responses. Gas chromatography-mass spectrometry (GC-MS), revealed 26 high-value bioactives, with diallyl disulphide being the most abundant (16.22 %), followed by 2,3-dihydro-3,5-dihydroxy-6-methyl, 4H-pyran-4-one and 5-Hydroxymethylfurfural. Additionally, in silico investigation indicated that stigmasterol, arbutin, squalene, α-tocopherol and linoleic acid were responsible for antihyperglycemic potential. Moreover, antimicrobial activity revealed that S. mutans (19.25±1.98 mm) and L. monocytogenes (19.34±2.04 mm) were the most sensitive, while P. aeruginosa was the least sensitive bacterial strains against the optimized NARC-G1 garlic extract. This research effectively explains the optimal recovery of high-valued components from NARC-G1 and may contribute to nutra-pharmaceutical and functional food developments.

13.
Geoderma ; 443: 116831, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38533356

RESUMO

Soils are a major player in the global carbon (C) cycle and climate change by functioning as a sink or a source of atmospheric carbon dioxide (CO2). The largest terrestrial C reservoir in soils comprises two main pools: organic (SOC) and inorganic C (SIC), each having distinct fates and functions but with a large disparity in global research attention. This study quantified global soil C research trends and the proportional focus on SOC and SIC pools based on a bibliometric analysis and raise the importance of SIC pools fully underrepresented in research, applications, and modeling. Studies on soil C pools started in 1905 and has produced over 47,000 publications (>1.7 million citations). Although the global C stocks down to 2 m depth are nearly the same for SOC and SIC, the research has dominantly examined SOC (>96 % of publications and citations) with a minimal share on SIC (<4%). Approximately 40 % of the soil C research was related to climate change. Despite poor coverage and publications, the climate change-related research impact (citations per document) of SIC studies was higher than that of SOC. Mineral associated organic carbon, machine learning, soil health, and biochar were the recent top trend topics for SOC research (2020-2023), whereas digital soil mapping, soil properties, soil acidification, and calcite were recent top trend topics for SIC. SOC research was contributed by 151 countries compared to 88 for SIC. As assessed by publications, soil C research was mainly concentrated in a few countries, with only 9 countries accounting for 70 % of the research. China and the USA were the major producers (45 %), collaborators (37 %), and funders of soil C research. SIC is a long-lived soil C pool with a turnover rate (leaching and recrystallization) of more than 1000 years in natural ecosystems, but intensive agricultural practices have accelerated SIC losses, making SIC an important player in global C cycle and climate change. The lack of attention and investment towards SIC research could jeopardize the ongoing efforts to mitigate climate change impacts to meet the 1.5-2.0 °C targets under the Paris Climate Agreement of 2015. This bibliographic study calls to expand the research focus on SIC and including SIC fluxes in C budgets and models, without which the representation of the global C cycle is incomplete.

14.
J Environ Manage ; 365: 121549, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955042

RESUMO

In this study, the authors projected the impacts of clean energy investment on environmental degradation by applying a novel and dynamic Autoregressive Distributed Lag (DARDL) model for Pakistan from 1990 to 2022. Most researchers have used ecological footprint or CO2 emissions indicators to look at how clean energy investment affects environmental degradation, which primarily represents contamination induced by humans' consumption patterns and does not consider the impact of the supply side. Against this background, the study scrutinized the dynamic interaction between clean energy investment and environmental sustainability using the load capacity factor (LCF) as an ecological indicator in Pakistan, including economic growth, population density, trade openness, urbanization, and industrialization in the analysis. The long-run estimates from DARDL indicate that a 1 percent upsurge in clean energy investment mitigates environmental degradation by approximately 0.42 percent on average, controlling for other factors. Further, the study also revealed that a 1 percent increase in clean energy investment diminishes dirty energy consumption by approximately 0.45 percent. The validity of the findings is confirmed using alternate methods, i.e., KRLS. The study recommends that Pakistan prioritize investment in clean energy projects to promote environmental sustainability and enforce environmental regulations to reduce the adverse externalities associated with dirty energy activities.


Assuntos
Investimentos em Saúde , Paquistão , Humanos , Meio Ambiente , Modelos Teóricos , Conservação dos Recursos Naturais
15.
J Environ Manage ; 353: 120174, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38316073

RESUMO

The pace of species extinction and deforestation has increased dramatically due to the substantial increase in global environmental degradation. This trend is approaching the crucial temperature threshold of 2 °C and calls for more attention. Although previous research has observed the individual impacts of forest depletion, structural change, economic growth, and urbanization on various sustainability outcomes, there has been no previous research into their interrelationships with an emphasis on the load capacity factor (LCF). Furthermore, no previous study has examined the environmental impacts of the abovementioned variables by contrasting the results of LCF and CO2 emissions in Pakistan. Therefore, this research suggests a theoretical framework that integrates these concepts, provides a roadmap for an effective and sustainable mitigation strategy for Pakistan and compares LCF results with CO2 emissions. Using the time-series data from 1970 to 2021, a unique and sophisticated dynamic Autoregressive Distributed Lag (DARDL) technique, the authors found that (i) a 1 % rise in forest depletion leads to a decline in load capacity factor by 0.026 %. (ii) A one per cent upsurge in structural change fosters environmental sustainability by raising the load capacity factor by 0.084 %. (iii) An increase of 1 % in economic growth dwindles the load capacity factor by 0.027 %. (iv) A one per cent surge in urbanization enhances the load capacity factor by 0.029 %. The findings suggest that Pakistan's Government should promote afforestation by emphasizing the constructive role of structural change in achieving environmental sustainability.


Assuntos
Dióxido de Carbono , Florestas , Paquistão , Dióxido de Carbono/análise , Desenvolvimento Econômico , Urbanização
16.
Antimicrob Agents Chemother ; 67(7): e0030923, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37366614

RESUMO

Cefepime has been reported to cause concentration-related neurotoxicity, especially in critically ill patients with renal failure. This evaluation aimed to identify a dosing regimen providing a sufficient probability of target attainment (PTA) and the lowest justifiable risk of neurotoxicity in critically ill patients. A population pharmacokinetic model was developed based on plasma concentrations over four consecutive days obtained from 14 intensive care unit (ICU) patients. The patients received a median dose of 2,000 mg cefepime by 30-min intravenous infusions with dosing intervals of every 8 h (q8h) to q24h. A time that the free drug concentration exceeds the MIC over the dosing interval (fT>MIC) of 65% and an fT>2×MIC of 100% were defined as treatment targets. Monte Carlo simulations were carried out to identify a dosing regimen for a PTA of 90% and a probability of neurotoxicity not exceeding 20%. A two-compartment model with linear elimination best described the data. Estimated creatinine clearance was significantly related to the clearance of cefepime in nondialysis patients. Interoccasion variability on clearance improved the model, reflecting dynamic clearance changes. The evaluations suggested combining thrice-daily administration as an appropriate choice. In patients with normal renal function (creatinine clearance, 120 mL/min), for the pharmacodynamics target of 100% fT>2×MIC and a PTA of 90%, a dose of 1,333 mg q8h was found to be related to a probability of neurotoxicity of ≤20% and to cover MICs up to 2 mg/L. Continuous infusion appears to be superior to other dosing regimens by providing higher efficacy and a low risk of neurotoxicity. The model makes it possible to improve the predicted balance between cefepime efficacy and neurotoxicity in critically ill patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT01793012).


Assuntos
Antibacterianos , Estado Terminal , Humanos , Cefepima/uso terapêutico , Estado Terminal/terapia , Creatinina , Antibacterianos/efeitos adversos , Mitomicina , Probabilidade , Testes de Sensibilidade Microbiana , Método de Monte Carlo
17.
BMC Plant Biol ; 23(1): 414, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679677

RESUMO

The application of germination models in economic crop management makes them extremely useful for predicting seed germination. Hence, we examined the effect of varying water potentials (Ψs; 0. - 0.3, - 0.6, - 0.9, - 1.2 MPa) and temperatures (Ts; 20, 25, 30, 35, 40 °C) on maize germination and enzymatic antioxidant mechanism. We observed that varying Ts and Ψs significantly influenced germination percentage (GP) and germination rate (GR), and other germination parameters, including germination rate index (GRI), germination index (GI), mean germination index (MGI), mean germination time (MGT), coefficient of the velocity of germination (CVG), and germination energy (GE) (p ≤ 0.01). Maximum (87.60) and minimum (55.20) hydro-time constant (θH) were reported at 35 °C and 20 °C, respectively. In addition, base water potential at 50 percentiles was highest at 30 °C (15.84 MPa) and lowest at 20 °C (15.46 MPa). Furthermore, the optimal, low, and ceiling T (To, Tb and Tc, respectively) were determined as 30 °C, 20 °C and 40 °C, respectively. The highest θT1 and θT2 were reported at 40 °C (0 MPa) and 20 °C (- 0.9 MPa), respectively. HTT has a higher value (R2 = 0.43 at 40 °C) at sub-optimal than supra-optimal temperatures (R2 = 0.41 at 40 °C). Antioxidant enzymes, including peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione peroxidase (GPX), increased with decreasing Ψs. In contrast, CAT and POD were higher at 20 °C and 40 °C but declined at 25, 30, and 35 °C. The APX and GPX remained unchanged at 20, 25, 30, and 40 °C but declined at 35 °C. Thus, maintaining enzymatic activity is a protective mechanism against oxidative stress. A decline in germination characteristics may result from energy diverting to anti-stress tools (antioxidant enzymes) necessary for eliminating reactive oxygen species (ROS) to reduce salinity-induced oxidative damage. The parameters examined in this study are easily applicable to simulation models of Z. mays L. germination under extreme environmental conditions characterized by water deficits and temperature fluctuations.


Assuntos
Antioxidantes , Zea mays , Pressão Osmótica , Temperatura , Germinação , Peroxidases , Peroxidase , Ascorbato Peroxidases
18.
Small ; 19(25): e2208179, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36935369

RESUMO

The realization of solar-light-driven CO2  reduction reactions (CO2 RR) is essential for the commercial development of renewable energy modules and the reduction of global CO2 emissions. Combining experimental measurements and theoretical calculations, to introduce boron dopants and nitrogen defects in graphitic carbon nitride (g-C3 N4 ), sodium borohydride is simply calcined with the mixture of g-C3 N4 (CN), followed by the introduction of ultrathin Co phthalocyanine through phosphate groups. By strengthening H-bonding interactions, the resultant CoPc/P-BNDCN nanocomposite showed excellent photocatalytic CO2 reduction activity, releasing 197.76 and 130.32 µmol h-1  g-1 CO and CH4 , respectively, and conveying an unprecedented 10-26-time improvement under visible-light irradiation. The substantial tuning is performed towards the conduction and valance band locations by B-dopants and N-defects to modulate the band structure for significantly accelerated CO2 RR. Through the use of ultrathin metal phthalocyanine assemblies that have a lot of single-atom sites, this work demonstrates a sustainable approach for achieving effective photocatalytic CO2 activation. More importantly, the excellent photoactivity is attributed to the fast charge separation via Z-scheme transfer mechanism formed by the universally facile strategy of dimension-matched ultrathin (≈4 nm) metal phthalocyanine-assisted nanocomposites.

19.
Glob Chang Biol ; 29(12): 3256-3270, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36994691

RESUMO

Mangroves are among the most carbon-dense ecosystems worldwide. Most of the carbon in mangroves is found belowground, and root production might be an important control of carbon accumulation, but has been rarely quantified and understood at the global scale. Here, we determined the global mangrove root production rate and its controls using a systematic review and a recently formalised, spatially explicit mangrove typology framework based on geomorphological settings. We found that global mangrove root production averaged ~770 ± 202 g of dry biomass m-2 year-1 globally, which is much higher than previously reported and close to the root production of the most productive tropical forests. Geomorphological settings exerted marked control over root production together with air temperature and precipitation (r2 ≈ 30%, p < .001). Our review shows that individual global changes (e.g. warming, eutrophication, drought) have antagonist effects on root production, but they have rarely been studied in combination. Based on this newly established root production rate, root-derived carbon might account for most of the total carbon buried in mangroves, and 19 Tg C lost in mangroves each year (e.g. as CO2 ). Inclusion of root production measurements in understudied geomorphological settings (i.e. deltas), regions (Indonesia, South America and Africa) and soil depth (>40 cm), as well as the creation of a mangrove root trait database will push forward our understanding of the global mangrove carbon cycle for now and the future. Overall, this review presents a comprehensive analysis of root production in mangroves, and highlights the central role of root production in the global mangrove carbon budget.


Assuntos
Carbono , Ecossistema , Áreas Alagadas , Biomassa , Florestas , Solo
20.
Langmuir ; 39(50): 18447-18457, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38055936

RESUMO

Graphene oxide-based composite membranes have received enormous attention for highly efficient water desalination. Herein, we prepare arginine/graphene oxide (Arg/GO) composite membranes by surface functionalizing GO nanosheets with arginine amino acid. Arginine has a unique combination of hydroxyl and amino functional groups that cross-link GO nanosheets through hydrogen bonding and electrostatic interactions. The as-prepared Arg@GO composite membranes with different thicknesses are used to separate the salt and dye molecules. The 900-nm-thick Arg@GO composite membrane shows high rejection of 98% for NaCl and 99.8% for MgCl2, Ni(NO3)2, and Pb(NO3)2 with good water permeance. Such a membrane also shows a high separation efficiency (100%) for methylene blue, rhodamine B, and Evans blue dyes. At the same time, the ultrathin Arg@GO composite membrane (220 ± 10 nm) exhibits high water permeance of up to 2100 ± 10 L m-2 h-1 bar-1. Furthermore, the 900-nm-thick Arg@GO composite membrane is stable in an aqueous environment for 40 days with significantly less swelling. Therefore, these membranes can be utilized in future desalination and separation applications.

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