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1.
Cytokine ; 156: 155917, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35660715

RESUMO

Gastrointestinal (GI) cancers refer to a group of malignancies associated with the GI tract (GIT). Like other solid tumors, hypoxic regions consistently feature inside the GI tumor microenvironment (TME) and contribute towards metabolic reprogramming of tumor-resident cells by modulating hypoxia-induced factors. We highlight here how the metabolic crosstalk between cancer cells and immune cells generate immunosuppressive environment inside hypoxic tumors. Given the fluctuating nature of tumor hypoxia, the metabolic fluxes between immune cells and cancer cells change dynamically. These changes alter cellular phenotypes and functions, resulting in the acceleration of cancer progression. These evolved properties of hypoxic tumors make metabolism-targeting monotherapy approaches or immunotherapy-measures unsuccessful. The current review highlights the advantages of combined immunometabolic treatment strategies to target hypoxic GI cancers and also identifies research areas to develop better combinational therapeutics for future.


Assuntos
Desastres , Neoplasias Gastrointestinais , Neoplasias , Neoplasias Gastrointestinais/terapia , Humanos , Hipóxia , Imunoterapia/métodos , Neoplasias/metabolismo , Microambiente Tumoral
2.
Clin Transplant ; 31(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27935642

RESUMO

AIM: The aim of this study was to evaluate long-term health-related quality of life (HRQOL), changes in lifestyle, and complications in living liver donors at a single transplant center from southern India. METHODS: A total of 64 consecutive living liver donors from 2008 to 2011 were evaluated; 46 of 64 donors completed the short form 36 (SF-36) via telephonic interviews or clinic consultations. Mean follow-up was 48 months (range: 37-84 months). RESULTS: There was no mortality in the donors evaluated. Overall morbidity was 23%, which included wound infections (4.3%), incisional hernia (2.1%), biliary leak (4.3%), and nonspecific complaints regarding the incision site (15.2%). All 46 donors who completed the SF-36 had no change in career path or predonation lifestyle. A total of 40 of 46 (87%) donors had no limitations, decrements, or disability in any domain, while six of 46 (13%) had these in some domains of which general health (GH) was most severely affected. CONCLUSIONS: Living donor hepatectomy is safe with acceptable morbidity and excellent long-term HRQOL with no change in career path or significant alteration of lifestyle for donors.


Assuntos
Transplante de Fígado , Doadores Vivos , Qualidade de Vida , Coleta de Tecidos e Órgãos , Adulto , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
3.
Small ; 11(3): 361-6, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25168184

RESUMO

Temperature and/or composition mapping inside high temperature energy conversion and storage devices are challenging, yet of critical importance to improve the material design for optimum performance. Here, the great potential of TiO2 nanoparticle (NP)-decorated graphite nanoplatelet (GNP) nanocomposites as high temperature thermal senors or gas sensors is reported. Effects of the GNP substrate on phonon confinement in Raman spectrum, grain growth, and phase stability of anatase TiO2 NPs at high temperatures are systematically studied. Thermally sensitive Raman signatures, indicating the ultrafast grain growth of TiO2 NPs in response to short thermal shock treatments (0.1-25 s) at high temperatures, are exploited for high temperature thermal sensing applications. A very high accuracy of nearly 98% in temperature measurements is demonstrated for a given short-time thermal exposure. Thermal stability of anatase TiO2 NPs against transformation into the rutile phase in TiO2 -GNP nancomposites is substantially increased by controlling the surface area of the substrate, which would significantly improve the performance of TiO2 -based high temperature gas sensors.

4.
J Phys Chem Lett ; 15(5): 1246-1253, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38277511

RESUMO

Metal-air batteries can play a crucial role in curbing air pollution due to carbon emission. Here, we report the hydrothermally synthesized bimetal oxides (NiFe2O4 and CoFe2O4) and their hybrid nanostructures with MoSe2 as potential electrocatalysts for electrically rechargeable Zn-air batteries. The NiFe2O4-MoSe2 hybrid nanostructure exhibits the best electrocatalytic activity (overpotential η10 ≈ 218 mV and Tafel slope ≈ 37 mV dec-1) for the OER study among prepared electrocatalysts in 1 M KOH electrolyte. Among the designed rechargeable Zn-air batteries, hybrid nanostructure-based batteries show superior performance, with the NiFe2O4-MoSe2 based device showing the best performance, having a high open-circuit voltage of ∼1.43 V, a peak power density of ∼176 mW cm-2, a specific capacity of ∼1025 mAh gZn-1, and an energy density of ∼1205 Wh kgZn-1. The superior performance of the hybrid nanostructures is due to the synergistic effect between MoSe2 and bimetal oxides, which enhances the conductivity, oxygen mobility, and active sites of the catalysts.

5.
Chempluschem ; : e202400278, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963318

RESUMO

Zinc-air batteries are promising energy storage devices owing to their high energy density, low cost, and environmental friendliness. However, the development of durable and efficient bifunctional electrocatalysts is a major concern for Zn-air batteries. In this review, we summarize the recent progress on transition metal dichalcogenides (TMDs) as bifunctional electrocatalysts for Zn-air batteries. We discuss the advantages of TMDs, such as high activity, good stability, and tunable electronic structure, as well as the challenges, such as low conductivity, poor durability, and limited active sites. We also highlight the strategies for fine-tuning the properties of TMDs, such as defect engineering, doping, hybridization, and structural engineering, to enhance their catalytic performance and stability. We provide a comprehensive and in-depth analysis of the applications of TMDs in Zn-air batteries, demonstrating their potential as low-cost, abundant, and environmentally friendly alternatives to noble metal catalysts. We also suggest future directions like exploring new TMDs materials and compositions, developing novel synthesis and modification techniques, investigating the interfacial interactions and charge transfer processes, and integrating TMDs with other functional materials. This review aims to illuminate the path forward for the development of efficient and durable Zn-air batteries, aligning with the broader objectives of sustainable energy solutions.

6.
J Hazard Mater ; 472: 134453, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38723481

RESUMO

Crop plants face complex tropospheric ozone (O3) stress, emphasizing the need for a food security-focused management strategy. While research extensively explores O3's harmful effects, this study delves into the combined impacts of O3 and CO2. This study investigates the contrasting responses of O3-sensitive (PBW-550) and O3-resistant (HUW-55) wheat cultivars, towards elevated ozone (eO3) and elevated carbon dioxide (eCO2), both individually and in combination. The output of the present study confirms the positive effect of eCO2 on wheat cultivars exposed to eO3 stress, with more prominent effects on O3-sensitive cultivar PBW-550, as compared to the O3-resistant HUW-55. The differential response of the two wheat cultivars can be attributed to the mechanistic variations in the enzyme activities of the Halliwell-Asada pathway (AsA-GSH cycle) and the ascorbate and glutathione pool. The results indicate that eCO2 was unable to uplift the regeneration of the glutathione pool in HUW-55, however, PBW-550 responded well, under similar eO3 conditions. The study's findings, highlighting mechanistic variations in antioxidants, show a more positive yield response in PBW-550 compared to HUW-55 under ECO treatment. This insight can inform agricultural strategies, emphasizing the use of O3-sensitive cultivars for sustained productivity in future conditions with high O3 and CO2 concentrations.


Assuntos
Ácido Ascórbico , Dióxido de Carbono , Glutationa , Ozônio , Triticum , Ozônio/toxicidade , Ozônio/farmacologia , Triticum/efeitos dos fármacos , Triticum/metabolismo , Dióxido de Carbono/metabolismo , Glutationa/metabolismo , Ácido Ascórbico/metabolismo , Poluentes Atmosféricos/toxicidade
7.
Biol Trace Elem Res ; 202(5): 1856-1865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37535217

RESUMO

Cutaneous leishmaniasis is a parasitic skin disease prevalent in many parts of the world. Zinc has been investigated for its potential role in the immune response against Leishmania parasites. This study aimed to systematically review the literature and conduct meta-analyses to evaluate the serum zinc level and efficacy of zinc therapy in cutaneous leishmaniasis. A comprehensive search of electronic databases was performed to find studies reporting serum zinc levels and the efficacy of zinc therapy in cutaneous leishmaniasis. Meta-analyses were conducted using RevMan software (version 5.4), calculating the mean difference for serum zinc levels and risk ratio for the efficacy of zinc therapy. A total of 11 studies with 1009 participants were evaluated. Five of these studies, comprising 637 participants, examined serum zinc levels; the remaining six, involving 372 individuals, examined the effectiveness of zinc therapy in treating cutaneous leishmaniasis. The results showed that the serum zinc level was significantly lower in cutaneous leishmaniasis patients compared to controls (MD: - 26.65; 95% CI: [- 42.74, - 10.57]; p = 0.001). However, zinc therapy did not demonstrate a significant clinical improvement compared to standard treatment (RR: 0.96; 95% CI: [0.74, 1.23], p = 0.73).


Assuntos
Leishmaniose Cutânea , Zinco , Humanos , Zinco/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico
8.
Nanoscale ; 15(40): 16480-16492, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37794765

RESUMO

Surface-enhanced Raman scattering (SERS) has attracted extensive attention for its rapid, ultra-sensitive, non-destructive and label-free fingerprint detection of trace molecules. Recently, two-dimensional transition metal dichalcogenides have been investigated as SERS substrates owing to their low cost, simple synthesis, excellent optical behavior, tunable bandgap, high carrier mobility and good biocompatibility. Here, we have synthesized 2H-MoS2 nanostructures of different morphologies (vertically and horizontally oriented) via the chemical vapor deposition (CVD) method on different substrates (FTO-coated glass, Si and SiO2-Si) and utilized them as SERS substrates for the detection of bilirubin and vitamin B12 biomolecules. The strong vibronic coupling within the charge transfer (CT) process leads to photo-induced charge transfer (PICT) resonance, showing enhanced SERS activity. This CT mechanism is further confirmed by observing quenching of the room temperature PL spectra and enhanced SERS signals of biomolecules over SERS substrates. To the best of our knowledge, the detection limit in this work (10-11 M for bilirubin and 10-8 M for vitamin B12) is considerably higher than previously reported values. The improved efficiency of the PICT process can be achieved at low temperature, and this is confirmed when performing low temperature-dependent photoluminescence (PL) studies on SERS substrates. Furthermore, we also demonstrated enhanced SERS activity at low temperature on CVD-grown pristine MoS2 films over different substrates for biomolecule detection for the first time, attributing this activity to the enhanced PICT process at low temperature.

9.
Front Plant Sci ; 14: 1125529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909422

RESUMO

The present study investigates the efficiency of nitrogen (N) amendments in the management of ozone (O3) stress in two varieties (Kashi Sheetal and Kashi Harittima) of Indian bean (Dolichos lablab L.). Two O3 concentrations, ambient (44.9 ppb) and elevated (74.64 ppb) were used, and each O3 concentration has 3 nitrogen (N) dose treatments viz recommended (N1), 1.5 times recommended (N2), 2 times recommended (N3) and no nitrogen, which served as control (C). The experiment concluded Kashi Sheetal as O3 tolerant, as compared to Kashi Harittima. N amendments were effective in the partial amelioration of O3 stress, with N2 being the most effective nitrogen dose, at both ambient and elevated O3 concentrations. Kashi Sheetal has been determined to be O3 tolerant due to greater endogenous levels of H2O2 accumulation and enzymatic antioxidant contents with O3 exposure. The O3-sensitive variety, Kashi Harittima, responded more positively to N treatments, at both O3 concentrations. The positive effect of N amendments is attributed to the stimulated antioxidative enzyme activity, rather than the biophysical processes like stomatal conductance. Strengthened defense upon N amendments was attributed to the enhanced activities of APX and GR in Kashi Sheetal, while in Kashi Harittima, the two enzymes (APX and GR) were coupled by SOD and CAT as well, during the reproductive phase. Yield (weight of seeds plant-1) increments upon N (N2) amendments were higher in Kashi Harittima (O3 sensitive), as compared to Kashi Sheetal (O3 tolerant) at both ambient and elevated O3 concentration, due to higher antioxidant enzymatic response and greater rate of photosynthesis in the former.

10.
Nanoscale Adv ; 5(10): 2756-2766, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37205289

RESUMO

Thermal transport and exciton dynamics of semiconducting transition metal dichalcogenides (TMDCs) play an immense role in next-generation electronic, photonic, and thermoelectric devices. In this work, we synthesize distinct morphologies (snow-like and hexagonal) of a trilayer MoSe2 film over the SiO2/Si substrate via the chemical vapor deposition (CVD) method and investigated their morphological dependent exciton dynamics and thermal transport behaviour for the first time to the best of our knowledge. Firstly, we studied the role of spin-orbit and interlayer couplings both theoretically as well as experimentally via first-principles density functional theory and photoluminescence study, respectively. Further, we demonstrate morphological dependent thermal sensitive exciton response at low temperatures (93-300 K), showing more dominant defect-bound excitons (EL) in snow-like MoSe2 compared to hexagonal morphology. We also examined the morphological-dependent phonon confinement and thermal transport behaviour using the optothermal Raman spectroscopy technique. To provide insights into the nonlinear temperature-dependent phonon anharmonicity, a semi-quantitative model comprising volume and temperature effects was used, divulging the dominance of three-phonon (four-phonon) scattering processes for thermal transport in hexagonal (snow-like) MoSe2. The morphological impact on thermal conductivity (ks) of MoSe2 has also been examined here by performing the optothermal Raman spectroscopy, showing ks ∼ 36 ± 6 W m-1 K-1 for snow-like and ∼41 ± 7 W m-1 K-1 for hexagonal MoSe2. Our research will contribute to the understanding of thermal transport behaviour in different morphologies of semiconducting MoSe2, finding suitability for next-generation optoelectronic devices.

11.
J Nanosci Nanotechnol ; 12(8): 6658-64, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962803

RESUMO

Recently, the focus on carbon based nanostructures for various applications has been due to their novel properties such as high electrical conductivity, high mechanical strength and high surface area. In the present work, we have investigated the charge storage capacity of modified graphite nanoplatelets and hybrid structure of graphite nanoplatelets-multiwalled carbon nanotubes (MWNTs). These MWNTs can be used as spacers to reduce the possibility of restacking of graphite nanoplatelets and hence increases the surface area of the hybrid carbon nanostructure thereby high degree of metal oxide decoration is achieved over the hybrid structure. MWNTs were prepared by catalytic chemical vapor deposition technique and further purified with air oxidation and acid treatment. Graphite was treated with conc. nitric acid and sulphuric acid in the volumetric ratio of 1:3 for 3 days and these modified graphite nanoplatelets were further stirred with MWNTs in equal weight ratio to form hybrid nanostructure. Further, ruthenium oxide (RuO2) nanoparticles were decorated on this hybrid structure using chemical route followed by calcination. RuO2 decorated hybrid carbon nanostructure was characterized by using X-ray diffraction, Electron microscopy and Raman spectroscopy. The performance of the hybrid structure based nanocomposite as electrochemical capacitor electrodes was analyzed by studing its capacitive and charge-discharge behaviours using cyclic voltammetry and chronopotentiometry techniques and the results have been discussed.

12.
J Clin Orthop Trauma ; 27: 101829, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35310788

RESUMO

Background: Obesity is a significant risk factor for developing knee osteoarthritis, and these cases suffer from complications following Total Knee Arthroplasty (TKA). An association between obesity and outcome after TKA is ambiguous. Knowledge is scarce about a definite relation between the two. This study aims to establish a correlation between obesity and early outcomes of TKA. Methods: This prospective cross-sectional study was done in cases undergoing primary knee arthroplasty between September 2019 to August 2020. Obesity was classified in all cases, and multiple variables like pain, functional status, Range of Motion, knee deformity, and Patient Response Outcome Measures were recorded. Statistical analysis was performed using SPSS Statistical Software version 22.0 and R.3.2.0. The level of statistical significance was taken as p < 0.05. Results: We studied 100 knees (37 bilateral and 26 unilateral) in 63 cases. Pain score decreased maximally in the normal and overweight group and minimal in class III obesity (p < 0.001). KSS, FKSS, and PROMs gradually improved in all, except in morbidly obese (p < 0.001). Although the improvement in all variables was minimum in class III obesity compared to other classes of obesity, the margin of difference from the preoperative period was maximum in class III obese participants. Conclusion: All cases, irrespective of class of obesity, experienced a comparable improvement in their knee function and improved quality of life. In addition, the TKA offered substantial benefits in terms of pain relief, knee stability, walking distance, range of movement of the knee, and stair climbing.

13.
ACS Omega ; 7(21): 18110-18121, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35664626

RESUMO

We report a comprehensive investigation of MnNi0.7Fe0.3Ge Heusler alloy to explore its magnetic, caloric, and electrical transport properties. The alloy undergoes a ferromagnetic transition across T C ∼ 212 K and a weak-antiferromagnetic transition across T t ∼ 180 K followed by a spin-glass transition below T f ∼ 51.85 K. A second-order phase transition across T C with mixed short and long-range magnetic interactions is confirmed through the critical exponent study and universal scaling of magnetic entropy and magnetoresistance. A weak first-order phase transition is evident across T t from magnetization and specific heat data. The frequency dependent cusp in χAC(T) along with the absence of a clear magnetic transition in specific heat C(T) and resistivity ρ(T) establish the spin glass behavior below T f. Mixed ferromagnetic and antiferromagnetic interactions with dominant ferromagnetic coupling, as revealed by density functional calculations, are experimentally evident from the large positive Weiss temperature, magnetic saturation, and negative magnetic-entropy and magnetoresistance.

14.
Science ; 375(6579): 455-460, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35084986

RESUMO

The evolution and diversification of ancient megathermal angiosperm lineages with Africa-India origins in Asian tropical forests is poorly understood because of the lack of reliable fossils. Our palaeobiogeographical analysis of pollen fossils from Africa and India combined with molecular data and fossil amber records suggest a tropical-African origin of Dipterocarpaceae during the mid-Cretaceous and its dispersal to India during the Late Maastrichtian and Paleocene, leading to range expansion of aseasonal dipterocarps on the Indian Plate. The India-Asia collision further facilitated the dispersal of dipterocarps from India to similar climatic zones in Southeast Asia, which supports their out-of-India migration. The dispersal pathway suggested for Dipterocarpaceae may provide a framework for an alternative biogeographic hypothesis for several megathermal angiosperm families that are presently widely distributed in Southeast Asia.


Assuntos
Fósseis , Malvales , Dispersão Vegetal , Pólen , África , Sudeste Asiático , Evolução Biológica , Clima , Ecossistema , Florestas , Índia , Ilhas , Malvales/anatomia & histologia , Malvales/classificação , Malvales/genética , Filogenia , Filogeografia , Pólen/anatomia & histologia , Floresta Úmida , Estações do Ano
15.
Cureus ; 13(3): e14175, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33936886

RESUMO

Introduction Most of the patients with rectal prolapse complain of fecal incontinence followed by constipation. Surgery is the only definitive treatment option for rectal prolapse. There are two approaches: either transanal/perineal or transabdominal. The abdominal procedures can be done in the open laparotomy method or laparoscopically. Suture rectopexy is a very old and popular method of treating rectal prolapse. Nowadays, rectopexy by laparoscopic approach is considered the gold standard treatment for rectal prolapse. The study has been conducted to compare both the procedures and their outcomes in terms of conditions associated with rectal prolapse. Methods All consecutive patients with full-thickness rectal prolapse who had attended the surgery outpatient department were included in the study. The patients had undergone either open suture rectopexy or laparoscopic rectopexy after randomization. Assessment of postoperative pain, mean days of hospital stay, constipation, and incontinence score along with operative time, recurrence within six months of follow-up, and time to resume bowel activity were done. The patients were followed up for 18 months at regular intervals. Results A total of 58 patients were included in the study: 27 in the open group and 31 in the laparoscopic group. The operative time was 102 minutes versus 129 minutes (p=0.0001) in the open and laparoscopic groups, respectively. The laparoscopic group had an earlier resumption of bowel activity (3.1 days vs. 1.4 days [p=0.0001]); fewer days of hospital stay (6.8 days vs. 2.5 days [p=0.0001]), less postoperative pain (mean visual analogue scale score for pain on postoperative day one 4.0 versus 3.1 [p=0.0035] and on postoperative day two 3.8 versus 2.2 [p=0.0001]). There was no significant difference in postoperative constipation score and incontinence score between the two groups. Conclusion Laparoscopic rectopexy results in lesser postoperative pain, lesser hospital stay, and better patient satisfaction than open rectopexy.

16.
J Phys Chem Lett ; 11(4): 1268-1275, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32003998

RESUMO

Large area growth of MoS2 can show great advances in optoelectronic devices due to its unique optical and electronic properties. Here, we directly grow vertically oriented and interconnected few-layer MoS2 over 1 × 1 cm2 of p-type Si substrate using CVD technique. We report for the first time the thermal conductivity of vertically oriented few-layer (VFL) MoS2 using the optothermal Raman technique. The reduced phonon-defect scattering due to minimal defects and strains in VFL MoS2 results in excellent thermal conductivity of 100 ± 14 W m-1 K-1 at room temperature. The photoluminescence and DFT study confirm the semiconducting behavior of VFL-MoS2. The VFL-MoS2/Si photodiode shows high photoresponsivity of 7.37 A W-1 at -2.0 V bias under 0.15 mW cm-2 intensity of 532 nm laser. The enhanced light trapping and highly exposed edges of VFL MoS2 due to vertical orientation, formation of efficient p-n junction at the MoS2/Si interface and effective charge separation leads to the excellent performance of grown VFL-MoS2 for optoelectronic applications.

17.
PLoS One ; 14(1): e0211325, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30682174

RESUMO

Water is one of the main agent of erosion in many environmental settings, but erosion rates derived from beryllium-10 (10Be) suggests that a relationship between precipitation and erosion rate is statistically non-significant on a global scale. This might be because of the strong influence of other variables on erosion rate. In this global 10Be compilation, we examine if mean annual precipitation has a statistically significant secondary control on erosion rate. Our secondary variable assessment suggests a significant secondary influence of precipitation on erosion rate. This is the first time that the influence of precipitation on 10Be-derived erosion rate is recognized on global scale. In fact, in areas where slope is <200m/km (~11°), precipitation influences erosion rate as much as mean basin slope, which has been recognized as the most important variable in previous 10Be compilations. In areas where elevation is <1000m and slope is <11°, the correlation between precipitation and erosion rate improves considerably. These results also suggest that erosion rate responds to change in mean annual precipitation nonlinearly and in three regimes: 1) it increases with an increase in precipitation until ~1000 mm/yr; 2) erosion rate stabilizes at ~1000 mm/yr and decreases slightly with increased precipitation until ~2200 mm/yr; and 3) it increases again with further increases in precipitation. This complex relationship between erosion rate and mean annual precipitation is best explained by the interrelationship between mean annual precipitation and vegetation. Increased vegetation, particularly the presence of trees, is widely recognized to lower erosion rate. Our results suggest that tree cover of 40% or more reduces erosion rate enough to outweigh the direct erosive effects of increased rainfall. Thus, precipitation emerges as a stronger secondary control on erosion rate in hyper-arid areas, as well as in hyper-wet areas. In contrast, the regime between ~1000 and ~2200 mm/yr is dominated by opposing relationships where higher rainfall acts to increase erosion rate, but more water also increases vegetation/tree cover, which slows erosion. These results suggest that when interpreting the sedimentological record, high sediment fluxes are expected to occur when forests transition to grasslands/savannahs; however, aridification of grasslands or savannahs into deserts will result in lower sediment fluxes. This study also implies that anthropogenic deforestation, particularly in regions with high rainfall, can greatly increase erosion.


Assuntos
Berílio/análise , Desenvolvimento Vegetal , Radioisótopos/análise , Chuva , Conservação dos Recursos Naturais , Ecossistema
18.
Chem Commun (Camb) ; 52(85): 12661-12664, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-27722614

RESUMO

The first report of oxygen functionalized few-layer graphene (OFG) having an interlayer distance of 3.6 Å as an excellent proton conductor (8.7 × 10-3 S cm-1 at 80 °C, 95% RH) utilizing hydrophilic oxygen functionalities present at sheet edges bypassing the theoretical limitation of proton conduction through a basal plane. The synthesized OFG also exhibited excellent supercapacitor performance (296 F g-1).

19.
Chem Commun (Camb) ; 52(89): 13179, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27774534

RESUMO

Correction for 'Proton conduction through oxygen functionalized few-layer graphene' by Chanderpratap Singh et al., Chem. Commun., 2016, 52, 12661-12664.

20.
Sci Rep ; 5: 15718, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26503125

RESUMO

Exfoliated transition metal dichalcogenides (TMDs) such as WS2 and MoS2 have shown exciting potential for energy storage, catalysis and optoelectronics. So far, solution based methods for scalable production of few-layer TMDs usually involve the use of organic solvents or dangerous chemicals. Here, we report an eco-friendly method for facile synthesis of few-layer WS2 and MoS2 nanosheets using dilute aqueous solution of household detergent. Short time sonication of varying amount of bulk samples in soapy water was used to scale up the production of nanosheets. Thermal stability, optical absorption and Raman spectra of as-synthesized WS2 and MoS2 nanosheets are in close agreement with those from other synthesis techniques. Efficient photocatalytic activity of TMDs nanosheets was demonstrated by decomposing Brilliant Green dye in aqueous solution under visible light irradiation. Our study shows the great potential of TMDs nanosheets for environmental remediation by degrading toxic industrial chemicals in wastewater using sunlight.

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