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1.
Chemistry ; 30(9): e202302900, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38105290

RESUMO

The catalytic mechanisms of nitrogen reduction reaction (NRR) on the pristine and Co/α-MoC(001) surfaces were explored by density functional theory calculations. The results show that the preferred pathway is that a direct N≡N cleavage occurs first, followed by continuous hydrogenations. The production of second NH3 molecule is identified as the rate-limiting step on both systems with kinetic barriers of 1.5 and 2.0 eV, respectively, indicating that N2 -to-NH3 transformation on bimetallic surface is more likely to occur. The two components of the bimetallic center play different roles during NRR process, in which Co atom does not directly participate in the binding of intermediates, but primarily serves as a reservoir of H atoms. This special synergy makes Co/α-MoC(001) have superior activity for ammonia synthesis. The introduction of Co not only facilitates N2 dissociation, but also accelerates the migration of H atom due to the antibonding characteristic of Co-H bond. This study offers a facile strategy for the rational design and development of efficient catalysts for ammonia synthesis and other reactions involving the hydrogenation processes.

2.
Biosci Biotechnol Biochem ; 88(5): 529-537, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38509025

RESUMO

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.


Assuntos
Sobrevivência Celular , Cinnamomum , Peróxido de Hidrogênio , Queratinócitos , Potencial da Membrana Mitocondrial , Mitocôndrias , Mitofagia , Estresse Oxidativo , Extratos Vegetais , Espécies Reativas de Oxigênio , Humanos , Mitofagia/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/citologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cinnamomum/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Folhas de Planta/química , Antioxidantes/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Sirolimo/farmacologia , Células HaCaT , Proteínas Quinases/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
3.
Aging Clin Exp Res ; 36(1): 10, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281223

RESUMO

BACKGROUND: Circulating metabolites (CM) play a pivotal role in our overall health, yet the current evidence concerning the involvement of diverse CM in benign prostatic hyperplasia (BPH) remains limited. Mendelian randomization (MR) offers a promising avenue to explore the potential impact of CM on BPH. METHODS: In a forward MR analysis, a cohort of 249 circulating metabolites was employed as exposures to investigate their potential associations with BPH risk. Conversely, in a reverse MR analysis, BPH was employed as an exposure to assess its effects on CM. RESULTS: The forward MR analysis discerned a linkage between six metabolites and BPH, with careful consideration to excluding heterogeneity and pleiotropy. Subsequently, the reverse MR analysis unveiled that nine metabolic compounds, mainly comprising phospholipids and triglycerides, potentially exhibit elevated levels in BPH patients. CONCLUSION: Bidirectional MR analysis furnishes genetic insight into the interplay between CM and BPH. The prominence of lipids and triglycerides emerges as significant factors intricately linked to BPH risk.


Assuntos
Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/genética , Hiperplasia , Análise da Randomização Mendeliana , Próstata , Triglicerídeos
4.
Small ; 18(4): e2106067, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34889049

RESUMO

Herein, a heterostructural hexagonal@tetragonal GeO2 (HT-GeO2 ) composite has been designed based on density functional theory (DFT) calculations and synthesized via an acidic-heating route dealt with rapid cooling, where the inner hexagonal GeO2 (H-GeO2 ) phase is covered by a porous layer of tetragonal GeO2 (T-GeO2 ) owing to HF etching. Interestingly, the HT-GeO2 electrode has a self-optimizing effect in lithium storage induced by heterointerface regulation, where the porous T-GeO2 layer on the surface of HT-GeO2 can act as not only a Li+ /electron conducting layer, but also a buffer layer, while the inner H-GeO2 phase can react preferentially with Li ions owing to lower intercalation energy, which is confirmed by operando XRD measurement contributing to thorough lithiation for HT-GeO2 . Moreover, the heterointerface can enhance the pseudocapacitance effect, which can boost the Li storage and accelerate the discharge-charge process. As a result, a large capacity of 984 mAh g-1 after 500 cycles at 2 A g-1 and a capacity of 430 mAh g-1 at a high current density of 20 A g-1 are delivered. This work provides an easy and efficient way to improve the cycling stability of the GeO2 anode, and the T-GeO2 phase would be a novel anode material in energy storage devices.

5.
Chemistry ; 28(19): e202104575, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35170133

RESUMO

Weak light absorption of common Ir(III) complexes (e. g., using phenylpyridine as the ligand) has hindered their applications in photocatalytic hydrogen generation from water as an efficient photosensitizer. To address this issue, a series of cyclometalated Ir(III) complexes (Ir1-Ir5), featuring different electron-donating substituents to enhance the absorptivity, have been synthesized and studied as photosensitizers (PSs) for light-driven hydrogen production from water. Ir6-Ir7 were prepared as fundamental systems for comparisons. Electron donors, including 9-phenylcarbazole, triphenylamine, 4,4'-dimethoxytriphenylamine, 4,4'-di(N-hexylcarbazole)triphenylamine moieties were introduced on 6-(thiophen-2-yl)phenanthridine-based cyclometalating (C^N) ligands to explore the donor effect on the hydrogen evolution performance of these cationic Ir(III) complexes. Remarkably, Ir4 with 4,4'-dimethoxytriphenylamine achieved the highest turn-over number (TON) of 12 300 and initial turnover frequency (TOFi ) of 394 h-1 , with initial activity (activityi ) of 547 000 µmol g-1 h-1 and initial apparent quantum yield (AQYi ) of 9.59 %, under the illumination of blue light-emitting diodes (LEDs) for 105 hours, which demonstrated a stable three-component photocatalytic system with high efficiency. The TON (based on n(H2 )/n(PSr)) in this study is the highest value reported to date among the similar photocatalytic systems using Ir(III) complexes with Pt nanoparticles as catalyst. The great potential of using triphenylamine-based Ir(III) PSs in boosting photocatalytic performance has also been shown.

6.
Arch Virol ; 167(2): 545-551, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35064833

RESUMO

Feline immunodeficiency virus (FIV) naturally infects more than 20 kinds of felines and poses a serious threat to their health, but there has been little research on FIV in tigers. In this study, 320 captive Siberian tigers (225 from Harbin, 55 from Hailin, and 40 from Shenyang) were tested for FIV by nested PCR, and three Siberian tigers from Hailin were FIV positive (5.45%). From these three animals, FIV gene fragments, gag-p26 (444 nt) from samples HD094 and HD1786 and pol-RT (576 nt) and pol-RNase (730 nt) from sample HD631, were sequenced and found to share more than 99% sequence identity with FIV subtype A from domestic cats. This is the first time FIV has been detected in Siberian tigers in China.


Assuntos
Vírus da Imunodeficiência Felina , Tigres , Animais , Gatos , China/epidemiologia , Vírus da Imunodeficiência Felina/genética
7.
Phys Chem Chem Phys ; 24(26): 16183-16192, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35749066

RESUMO

First-principles calculations based on density functional theory were utilized to study the performance of Na2ZrO3 (NZO) and yttrium-doped Na2ZrO3 (Y-NZO) as cathode materials for sodium ion batteries (SIBs), including the stability of the desodiated structures, desodiation energy, redox mechanism, and the diffusion of Na. When 62.5% sodium is removed from NZO, its structure and volume change little and the layered structure is retained, whereas the structure starts to distort and shift to the ZrO3 phase with the extraction of more than 62.5% sodium. As desodiation proceeds, oxygen anions act as the only redox center for charge compensation, yielding a high initial voltage of 4.03 eV vs. Na/Na+ by PBE + U-D3 functional and 4.82 eV vs. Na/Na+ by HSE06-D3 functional. When the desodiation content is less than 31.25%, O23- is formed with an O-O distance of 2.38 Å. At the desodiation content of 31.25%, peroxide dimer O22- starts to form; at the desodiation content of 56.25%, the O-O bond distance is further shortened to 1.3 Å, corresponding to the formation of superoxide O2-. However, for Y-NZO, the redox reaction firstly involves O2-/O1-, which does not occur in NZO. Peroxides and superoxides appear when the sodium removal concentration is 59.38% and 75%, respectively. This indicates that the O-O dimers appear in Y-NZO at much deeper sodium removal. The calculations of diffusion paths and barriers of Na ions in NZO by PBE + U-D3 predict that the barrier of Na escaping from the mixed layer to the Na layer in NZO is 0.48 eV (the reverse barrier is 0.76 eV), smaller than those of other O3-type layered transition metal compounds, such as Na2IrO3 and Na2RuO3. After yttrium doping, the diffusion of Na ions becomes easier, indicating that the Y-doping improves the diffusion ability. This investigation interprets the mechanism of oxygen oxidation of NZO as a cathode for SIBs, and provides theoretical support for a better design of Na-rich layered oxide Na2MO3 (M represents the transition metal element) in the future research.

8.
J Chem Phys ; 156(20): 204702, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35649874

RESUMO

The properties of KTiOPO4Mx (M = K, Na, and Li; x = 0.000-1.000) as an anode for potassium-ion batteries (PIBs), sodium-ion batteries (SIBs), and lithium-ion batteries (LIBs) are investigated by density functional theory calculations. Our work reveals that the electrochemical performance of KTiOPO4 as an anode for PIBs is superior to that for SIBs and LIBs, in terms of average voltage and ion diffusion kinetics. The ab initio molecular dynamics simulations indicate that the KTiOPO4Mx anode exhibits high structural stability, and alkali ion intercalation contributes to accelerating ion diffusion during the charging process. Particularly, the low activation energy of 0.406 eV of K migration on surface KTP(210), obtained by the climbing-image nudged elastic band method, suggests a high-rate capability. The systematical comparison of the performance of KTiOPO4 as an anode for PIBs, SIBs, and LIBs on the theoretical perspective clarifies that a large channel is not always promising for small radius ion intercalation and diffusion.

9.
Angew Chem Int Ed Engl ; 61(39): e202204561, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35931663

RESUMO

Developing light-harvesting materials with broad spectral response is of fundamental importance in full-spectrum solar energy conversion. We found that, when a series of earth-abundant metal (Cu, Co, Ni and Fe) salts are dissolved in coordinating solvents uniformly dispersed nanodots (NDs) are formed rather than fully dissolving as molecular species. The previously unrecognized formation of this condensed state is ascribed to spontaneous aggregation of molecular transition-metal-complexes (TMCs) via weak intermolecular interactions, which results in redshifted and broadened absorption into the NIR region (200-1100 nm). Typical photoredox reactions, such as carbonylation and oxidative dehydrogenation, well demonstrate the feasibility of efficient utilization of NIR light (λ>780 nm) by TMCs NDs. Our finding provides a conceptually new strategy for extending the absorption towards low energy photons in solar energy harvesting and conversion via photoredox transformations.

10.
J Org Chem ; 86(21): 15284-15297, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34647457

RESUMO

Energy transfer plays a special role in photocatalysis by utilizing the potential energy of the excited state through indirect excitation, in which a photosensitizer determines the thermodynamic feasibility of the reaction. Bioinspired by the energy-transfer ability of natural product cercosporin, here we developed a green and highly efficient organic photosensitizer HiBRCP (hexaisobutyryl reduced cercosporin) through structural modification of cercosporin. After structural manipulation, its triplet energy was greatly improved, and then, it could markedly promote the efficient geometrical isomerization of alkenes from the E-isomer to the Z-isomer. Moreover, it was also effective for energy-transfer-mediated organometallic catalysis, which allowed realization of the cross-coupling of aryl bromides and carboxylic acids through efficient energy transfer from HiBRCP to nickel complexes. Thus, the study on the relationship between structural manipulation and their photophysical properties provided guidance for further modification of cercosporin, which could be applied to more meaningful and challenging energy-transfer reactions.


Assuntos
Alcenos , Níquel , Brometos , Catálise , Transferência de Energia
11.
Arch Virol ; 166(12): 3427-3431, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34536127

RESUMO

Here, we report the discovery and molecular characterization of a novel mitovirus isolated from tissues of Lagenaria siceraria, named "Lagenaria siceraria associated mitovirus 1" (LsaMV1). Next-generation sequencing and adapter-ligation-mediated amplification were used to obtain the full-length genome sequence of LsaMV1. The genome of LsaMV1 is 3,098 nucleotides (nt) long and contains an opening reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRP). Homology searches and phylogenetic analysis of the 855-aa RdRP suggested that LsaMV1 is a member of a new species in the family Mitoviridae. This is the first report of a member of the family Mitoviridae associated with the important summer vegetable bottle gourd.


Assuntos
Genoma Viral , Vírus de RNA , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Filogenia , Vírus de RNA/genética , RNA Viral/genética
12.
Phys Chem Chem Phys ; 23(19): 11528-11537, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33960343

RESUMO

Ni-rich layered oxides, like LiNi0.8Co0.1Mn0.1O2 (NCM811), have been widely investigated as cathodes due to their high energy density. However, gradual structural transformation during cycling can lead to capacity degradation and potential decay of cathode materials. Herein, we doped high-valence transition metal (TM) ions (V5+, Nb5+, and Zr4+) at the Ni site of NCM811 by first principles simulations and explored the mechanism of doping TMs in NCMs for enhancing the electrochemical performance. Analysis of the calculations shows that doping V, Nb and Zr has an efficient influence on alleviating the Ni oxidation, reducing the loss of oxygen, and facilitating Li+ migration. Moreover, V doping can further suppress the lattice distortion due to the radius of V5+ being close to the radius of Mn4+. In particular, compared with the barrier of the pristine NCM in Li divacancy, the barrier of V-doped NCM reaches the lowest. In conclusion, V is the most favorable dopant for NCM811 to improve the electrochemical properties and achieve both high capacity and cycling stability.

13.
Phys Chem Chem Phys ; 23(9): 5143-5151, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33624671

RESUMO

Based on first-principle calculations, we proposed a one two-dimensional (2D) blue AsP (b-AsP) monolayer as an ideal anode material for lithium/sodium-ion (Li/Na-ion) batteries for the first time. The b-AsP monolayer possesses thermal and dynamic stabilities. The system undergoes the transition from semiconductor to metal after Li/Na atoms are embedded, which ensures good electric transportation. Most remarkably, our results indicate that the b-AsP monolayer exhibits high theoretical capacities of 1011.2 mA h g-1 (for Li) and 1769.6 mA h g-1 (for Na), low average open circuit voltages of 0.17 eV for Li4AsP and 0.14 eV for Na7AsP systems and ultrafast diffusivity with the low energy barriers of 0.17/0.15 eV and 0.08/0.07 eV of the P/As sides for Li and Na, respectively. Given these exceptional properties, the synthesis of a buckled b-AsP monolayer is desired to achieve a promising electrode material for Li- and Na-ion batteries.

14.
J Chem Phys ; 154(5): 054703, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33557547

RESUMO

Density functional theory calculations have been performed to study the reaction mechanism of N2 thermal reduction (N2TR) over a single metal atom incorporated nitrogen-doped graphene. Our results reveal that the type of metal atoms and their coordination environments have a significant effect on the catalytic activity of N2TR. Regarding CoN4- and FeN4-embedded graphene sheets that the metal atom is fourfold coordinated, they are inactive for N2TR owing to the poor stability of the adsorbed H2 and N2 molecules. In contrast, if the monodisperse metal atom is surrounded by three N atoms, namely, CoN3/G and FeN3/G show activity toward N2TR, and catalytic conversion of N2 into ammonia is achieved through the associative mechanism rather than the dissociative mechanism. Further investigations show that the synthesis of NH3 over the two surfaces is mainly through the formation of an NHNH* intermediate; however, the detailed reaction mechanisms are sensitive to the type of metal atom introduced into N-doped graphene. Based on the calculated kinetic barriers, FeN3/G exhibits a better catalytic activity for N2TR. The superior performance of FeN3/G can be attributed to the fact that this surface prefers a high spin-polarized state during the whole process of N2TR, while the non-spin polarized state is predicted as the ground state for most of the elementary steps of N2-fixation over CoN3/G. The present study provides theoretical insights into developing graphene-based single atom catalysts with a high activity toward ammonia synthesis through N2TR.

15.
J Therm Biol ; 98: 102948, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34016365

RESUMO

Climate warming may have an impact on invasive species and their ecological consequences. Invasive reptiles, which have temperature-dependent physiology, are expected to be greatly impacted by climate warming, though data supporting this is limited. We investigated the potential impact of a warmer climate on an invasive lizard, Eutropis multifasciata, in Taiwan. A mechanistic model, NicheMapR, was used to simulate the maximum activity time available at three elevations, with varying forest densities, under the current climate and a warmer scenario. The results show that climate warming will provide this species more time for activity in the currently occupied lowland region but not in the mountain areas, which are covered with dense forests. However, if the landscape becomes more open in mountain areas, it will become more suitable for this species and may enable an expansion upslope. Our results show that climate warming has a positive impact on this species, and that landscape's characteristics profoundly modulate its impact and the possibilities for elevational expansion in the future.


Assuntos
Mudança Climática , Espécies Introduzidas , Lagartos/fisiologia , Altitude , Animais , Temperatura Corporal , Feminino , Florestas , Masculino , Modelos Teóricos , Solo , Taiwan , Temperatura
16.
Epidemiol Infect ; 148: e125, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32580792

RESUMO

The clinical characteristics of patients with COVID-19 were analysed to determine the factors influencing the prognosis and virus shedding time to facilitate early detection of disease progression. Logistic regression analysis was used to explore the relationships among prognosis, clinical characteristics and laboratory indexes. The predictive value of this model was assessed with receiver operating characteristic curve analysis, calibration and internal validation. The viral shedding duration was calculated using the Kaplan-Meier method, and the prognostic factors were analysed by univariate log-rank analysis and the Cox proportional hazards model. A retrospective study was carried out with patients with COVID-19 in Tianjin, China. A total of 185 patients were included, 27 (14.59%) of whom were severely ill at the time of discharge and three (1.6%) of whom died. Our findings demonstrate that patients with an advanced age, diabetes, a low PaO2/FiO2 value and delayed treatment should be carefully monitored for disease progression to reduce the incidence of severe disease. Hypoproteinaemia and the fever duration warrant special attention. Timely interventions in symptomatic patients and a time from symptom onset to treatment <4 days can shorten the duration of viral shedding.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Eliminação de Partículas Virais/fisiologia , Adulto , Análise de Variância , COVID-19 , China , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Progressão da Doença , Feminino , Humanos , Hipoproteinemia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Fatores de Tempo
17.
Oecologia ; 192(3): 657-669, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006183

RESUMO

Accurate evaluation of habitat availability for wildlife is relevant for ecological applications. Researchers have frequently used models to simulate habitats thermally suitable for reptiles, but these results have limited application for species highly selective for habitat humidity. Here, we use the biophysical Niche Mapper™ model to investigate impacts of vegetation cover on the habitat quality of a high-elevation forest skink, Sphenomorphus taiwanensis, and to predict changes in habitat suitability in a future warmer climate (3 °C increase in air temperature). We assess habitat suitability with different densities of canopy cover in our study areas using two ecologically relevant estimates for lizards: maximum activity time and evaporative water loss (EWL) during the activity season. We measured preferred body temperature and EWL of this species for model parameterization, and behavioral response to EWL to supplement habitat quality assessment. The results indicated that this species is sensitive to EWL and reduces its activity when dehydrated. The model predicted that denser canopy levels increase microclimate cooling and humidity, and that most canopy levels are thermally suitable for this species, as the lizard can thermoregulate to manage adverse temperatures. Nevertheless, increasing canopy density could significantly decrease EWL during activity. In the warmer climate scenario, simulated maximum activity time and EWL changed little because of thermoregulation behavior. Our results suggest that habitat preference of this species is a consequence of water and energy requirements, and we note that combining EWL and maximum activity time data can enhance model accuracy of lizards' habitat quality in a warmer climate.


Assuntos
Lagartos , Água , Animais , Ecossistema , Florestas , Microclima
18.
J Therm Biol ; 93: 102730, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33077141

RESUMO

1: The decrease of temperatures along an elevation gradient imposes physiological constraints on reptiles that ultimately determine their distribution ranges. Forest patterns are likely to interact with this process, but very few studies have examined their contribution in determining distribution limits. 2: We examined the role played by thermal physiology and forest cover in determining the elevational ranges of a lizard, Eutropis longicaudata. We integrated this species' thermal traits in simulating its maximum activity time under different conditions of forest cover and elevation using a NicheMapR model. In addition, we evaluated the influence of winter temperatures on the range limit by examining the simulated soil temperatures at the occurrence sites. 3: Laboratory experiments showed that E. longicaudata has a high preferred body temperature and low cold tolerance. The model predicts that maximum activity time decreases with elevation and forest cover. Although unforested areas may provide longer active time in all simulated elevations, mountain areas in Taiwan are heavily forested and are predicted to allow only a very short period of activity above 1000 m elevation. 4: All sightings were indeed located in areas below 1000 m elevation, in which the predicted average soil temperature is above 10 °C in January in cold years. 5: Our results show that reptile physiological response does respond strongly to the change of microclimate induced by forest cover and elevation. Overall, this suggests that forest cover is a major determinant of some reptiles' elevational range.


Assuntos
Aclimatação , Altitude , Temperatura Corporal , Lagartos/fisiologia , Temperatura , Distribuição Animal , Animais , Florestas , Taiwan
19.
J Therm Biol ; 87: 102475, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32001018

RESUMO

1. Temperature rise due to climate change affects seasonal activity times, leading to a discordance of phenology among species and changing the strength of interaction between species. Understanding how temperature changes will affect the length of a species' activity period is essential in order to forecast its response to climate warming. 2. We investigated the thermal physiology and monthly activity of a skink from subtropical areas in Taiwan, Scincella formosensis. In addition, we predicted its response to climate warming and potential landscape vegetation changes using a mechanistic model, Niche MapperTM. We incorporated the animals' thermal traits and climatic data to simulate thermally suitable time for activity each month in two sites (open area, dense forest). 3. We found that this species restricts its activity to the cool months of the year, and that juveniles emerge in June. The thermally suitable period for activity is predicted to be longer in cool months than warm months. 4. Our model predicts that a 3 °C increase in temperature will curtail the thermally suitable time for activity in open areas in late spring and result in very minimal time for activity in the summer, even when dense forest is available. These results add to the growing body of literature indicating that a temperature rise will have a widespread impact on sub/tropical forest reptiles.


Assuntos
Comportamento Animal , Mudança Climática , Lagartos/fisiologia , Aclimatação , Animais , Temperatura Corporal , Movimento , Estações do Ano , Taiwan , Clima Tropical
20.
Small ; 15(51): e1903904, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31747125

RESUMO

In the present work, a hierarchical composite of rose-like VS2 @S/N-doped carbon (VS2 @SNC) with expanded (001) planes is successfully fabricated through a facile synthetic route. Notably, the d-spacing of (001) planes is expanded to 0.92 nm, which is proved to dramatically reduce the energy barrier for Li+ diffusion in the composite of VS2 @SNC by density functional theory calculation. On the other hand, the S/N-doped carbon in the composite greatly promotes the electrical conductivity and enhances the structural stability. In addition, the hierarchical structure of VS2 @SNC facilitates rapid electrolyte diffusion and increases the contact area between the electrode and electrolyte simultaneously. Benefiting from the merits mentioned above, the VS2 @SNC electrode exhibits excellent electrochemical properties, such as a large reversible capacity of 971.6 mA h g-1 at 0.2 A g-1 , an extremely high rate capability of 772.1 mA h g-1 at 10 A g-1 , and a remarkable cycling stability up to 600 cycles at 8 A g-1 with a capacity of 684.5 mA h g-1 , making it a promising candidate as an anode material for lithium-ion batteries.

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