RESUMO
Coral reefs in the Central Indo-Pacific region comprise some of the most diverse and yet threatened marine habitats. While reef monitoring has grown throughout the region in recent years, studies of coral reef benthic cover remain limited in spatial and temporal scales. Here, we analysed 24,365 reef surveys performed over 37 years at 1972 sites throughout East Asia by the Global Coral Reef Monitoring Network using Bayesian approaches. Our results show that overall coral cover at surveyed reefs has not declined as suggested in previous studies and compared to reef regions like the Caribbean. Concurrently, macroalgal cover has not increased, with no indications of phase shifts from coral to macroalgal dominance on reefs. Yet, models incorporating socio-economic and environmental variables reveal negative associations of coral cover with coastal urbanisation and sea surface temperature. The diversity of reef assemblages may have mitigated cover declines thus far, but climate change could threaten reef resilience. We recommend prioritisation of regionally coordinated, locally collaborative long-term studies for better contextualisation of monitoring data and analyses, which are essential for achieving reef conservation goals.
Assuntos
Antozoários , Recifes de Corais , Animais , Teorema de Bayes , Oceanos e MaresRESUMO
Objective: To analyze whether there are differences and related influencing factors in liver injury associated with different strains of 2019-nCoV/SARS-CoV-2 infection. Methods: Data of epidemiology, clinical symptoms, laboratory tests, and treatment outcomes of patients with COVID-19 infection confirmed with Alpha and Delta virus strain in Zhejiang Province were retrospectively collected. Statistical analysis was performed using independent samples t-test or Mann-Whitney U test, χ2 test or Fisher's exact test, and logistic regression analysis. Results: A total of 788 and 381 cases with Alpha and Delta virus strain were included. Vaccination ratio was 0% in Alpha and 85.30% in Delta group (P<0.001), The proportion of patients with fever (80.71% vs. 40.94%, P<0.001) was significantly higher in Alpha than Delta strain group. The proportion of critical ill patients was significantly higher in Delta group (9.90% vs. 1.57%, respectively, P<0.001). The virus negative conversion time was significantly longer in Delta than Alpha group (22 d vs. 11 d, P<0.001), but the incidence of liver injury was significantly higher in Alpha than Delta group (20.05% vs. 13.91%, P=0.011). Univariate analysis showed that Alpha virus strain infection, male sex, body mass index, chronic liver disease, fever, diarrhea, shortness of breath, severe/critical illness, elevated creatine kinase (CK), elevated international normalized ratio (INR) and an elevated neutrophil/lymphocyte ratio was significantly associated with an increased risk of liver injury occurrence, and in patients with pharyngeal pain the risk of liver injury occurrence was significantly reduced. Multivariate analysis showed that shortness of breath [OR, 2.667 (CI: 1.389-5.122); P=0.003], increased CK [OR, 2.544 (CI: 1.414-4.576); P=0.002] and increased INR [OR, 1.721] (CI: 1.074-2.758); P=0.024] was significantly associated with an increased risk of liver injury occurrence, and in patients with pharyngeal pain the risk of liver injury occurrence was significantly reduced [OR, 0.424 (CI: 0.254-0.709); P=0.001]. Conclusion: Although the virulence of the Delta is stronger than Alpha strain, most patients infected with Delta strain vaccinated against COVID-19 in Zhejiang province had milder clinical symptoms and a lower incidence and degree of liver injury. Notably, the infection risk even remains after vaccination; however, symptoms and the incidence of severe and critical illness can be significantly reduced.
Assuntos
COVID-19 , Estado Terminal , Dispneia , Febre , Humanos , Fígado , Masculino , Dor , Estudos Retrospectivos , SARS-CoV-2RESUMO
Objective: To observe the efficacy and safety of de novo combination of Lamivudine(LAM) and Adefovir Dipivoxil (ADV) therapy counter to Entecavir (ETV) monotherapy in patients with chronic hepatitis B (CHB)- related compensated liver cirrhosis. Methods: Patients with chronic hepatitis B-related compensated cirrhosis who were initially treated with LAM and ADV for more than 1 year were randomly assigned to two groups, one half replaced with ETV monotherapy, and the other half continued LAM and ADV co-therapy. Liver biochemistry, renal biochemistry, estimated glomerular filtration rate, alpha-fetoprotein, HBV serology markers and serum HBV DNA were measured every 3 months. Urine ß2-microglobulin was measured every 6 months And retinol binding protein, followed up for 3 years. The mean values of the two groups were compared with t-test, and the rate of comparison was analyzed by x2 test. Results: A total of 580 cases were collected, 290 cases were replaced with ETV monotherapy, the other 290 patients continued to LAM and ADV combination therapy. In the ETV group, the rates of HBV DNA negative conversion at 1 year, 2 years and 3 years were 77.6%, 84.5% and 94.5% respectively, while the HBV DNA negative conversion rates at 1, 2 and 3 years in the LAM and ADV combination groups were 69.3%, 73.4% and 80.3% respectively. Among them, the negative rates of HBV DNA in the second year and the third year were P < 0.05, the difference was statistically significant. The 3-year cumulative gene-resistant rate in the ETV group was 1.4%, while the combined treatment was as high as 8.6%, and the difference was statistically significant in the two groups. The estimated value of serum creatinine and glomerular filtration rate in ETV group was followed by 3 years, and the baseline level was maintained, in the same group, the serum creatinine was higher than baseline, and the estimated value of glomerular filtration rate decreased. The results showed that there were 6.2%, 12.1%, 22.1% and 0, 0.3%, 1%, respectively, in 1, 2 and 3 years for the group of consecutive treatment and the replacement of ETV Group. The estimated glomerular filtration rate decreased by more than 30% compared with the baseline. The difference was statistically significant; the proportion of serum creatinine in the 1 year, 2 years and 3 years of the combined treatment group was 1.7%, 4.5% and 6.6%, compared with the baseline rise of > 50 µmol/l, and the ETV group was replaced in the 1 year, The values of 2 and 3 years were 0,0,0.7%, of which the 2nd and 3rd years were statistically significant; the proportion of microalbuminuria and retinol-binding protein in patients with combined treatment group was also significantly higher than that of Β2-m ETV Group. Conclusion: The initial combination of LAM and ADV therapy is inferior in terms of ETV monotherapy. Single therapy with ETV increase the rate of viral response, reduce the incidence of drug resistance, and also reduce the incidence of renal impairment in patients with chronic hepatitis B -related compensated liver cirrhosis.
Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , DNA Viral , Farmacorresistência Viral , Quimioterapia Combinada , Guanina/uso terapêutico , Vírus da Hepatite B/isolamento & purificação , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/virologia , Resultado do TratamentoRESUMO
Nickel metal hydride (Ni-MH) batteries have demonstrated key technology advantages for applications in new-energy vehicles, which play an important role in reducing greenhouse gas emissions and the world's dependence on fossil fuels. However, the poor high-rate dischargeability of the negative electrode materials-hydrogen storage alloys (HSAs) limits applications of Ni-MH batteries in high-power fields due to large polarization. Here we design a hybrid electrode by integrating HSAs with a current collector of three-dimensional bicontinuous nanoporous Ni. The electrode shows enhanced high-rate dischargeability with the capacity retention rate reaching 44.6% at a discharge current density of 3000 mA g(-1), which is 2.4 times that of bare HSAs (18.8%). Such a unique hybrid architecture not only enhances charge transfer between nanoporous Ni and HSAs, but also facilitates rapid diffusion of hydrogen atoms in HSAs. The developed HSAs/nanoporous metals hybrid structures exhibit great potential to be candidates as electrodes in high-performance Ni-MH batteries towards applications in new-energy vehicles.
RESUMO
Nitrogen-doped carbon nanotubes (NCNTs) are attractive for electrocatalytic applications in fuel cells due to their low cost and high electrocatalytic activity. By using density functional theory calculations, the electrocatalytic mechanisms of the oxygen reduction reaction (ORR) under electrochemical conditions are studied at graphite-like N groups (N(G)) and pyridine-like N groups (N(P)) of NCNTs, in which the effect of electrode potentials on the activation energy (E(a)) and reaction energy (E(r)) is taken into account. The ORR occurs at both N(G) and N(P) defect sites via two different four-electron OOH and two-electron H(2)O(2) mechanisms. At the lower potential region, both mechanisms are simultaneously responsible for the reaction at N(G) and N(P) defect sites; while at higher potentials, the four-electron mechanism becomes dominant and the ORR at N(P) defect sites is more energetically favorable than that at N(G) defect sites.
RESUMO
In this work, the glass transition of water was studied with density functional theory. The transition temperature was determined by measuring the heat capacity Cp of low-density amorphous water during rapid heating. This technique ensures that all measurements were implemented without crystallization occurring, which is difficult to be achieved experimentally. The results showed that the glass transition occurs at 171 K, which is much higher than the reported value of 136 K. In addition, the triply hydrogen-bonded water molecules were found when T > 180 K, demonstrating the existence of the liquid structure at the higher temperature range.
RESUMO
Electronic structures of hexagonal ice (ice Ih), high-density amorphous ice (HDA), and very high-density amorphous ice (VHDA) are investigated using ab initio density functional theory (DFT) at 77 K under a pressure of 0.1 MPa, focusing on band structure, density of states (DOS), partial density of states (PDOS), and electron density. It is found that the integration intensity of the O-2p bonding band in HDA is 1.53 eV wider than that in the VHDA. Because more 2p electrons in HDA participate the 2p-1s hybridization of O-H. The classical molecular dynamics (MD) method has further been carried out to analyze the hydrogen bond network of HDA and VHDA with larger numbers of water molecules under the same temperature, pressure, and boundary conditions used as those during the DFT calculation. MD results show that there exists some water molecules with five hydrogen bonds in both HDA (4.1 +/- 0.1%) and VHDA (2.8 +/- 0.1%), as compared with the LDA, being consistent with the integration intensity results of PDOS. This result can be used to interpret the physical nature of the similar transition temperature of HDA and VHDA to LDA with different heating rates.