Current climate models often have significant wet biases in the Tibetan Plateau and encounter particular difficulties in representing the climatic effect of the Central Himalaya Mountain (CHM), where ...the gradient of elevation is extremely steep and the terrain is complex. Yet, there were few studies dealing with the issue in the high altitudes of this region. In order to improve climate modeling in this region, a network consisting of 14 rain gauges was set up at elevations > 2800 m above sea level along a CHM valley. Numerical experiments with Weather Research and Forecasting model were conducted to investigate the effects of meso- and micro-scale terrain on water vapor transport and precipitation. The control case uses a high horizontal resolution (0.03°) and a Turbulent Orographic Form Drag (TOFD) scheme to resolve the mesoscale terrain and to represent sub-grid microscale terrain effect. The effects of the horizontal resolution and the TOFD scheme were then analyzed through comparisons with sensitivity cases that either use a low horizontal resolution (0.09°) or switch off the TOFD scheme. The results show that the simulations with high horizontal resolution, even without the TOFD scheme, can not only increase the spatial consistency (correlation coefficient 0.84–0.92) between the observed and simulated precipitation, but also considerably reduce the wet bias by more than 250%. Adding the TOFD scheme further reduces the precipitation bias by 50% or so at almost all stations in the CHM. The TOFD scheme reduces precipitation intensity, especially heavy precipitation (> 10 mm h
−1
) over high altitudes of the CHM. Both high horizontal resolution and TOFD enhance the orographic drag to slow down wind; as a result, less water vapor is transported from lowland to the high altitudes of CHM, causing more precipitation at lowland area of the CHM and less at high altitudes of CHM. Therefore, in this highly terrain-complex region, it is crucial to use a high horizontal resolution to depict mesoscale complex terrain and a TOFD scheme to parameterize the drag caused by microscale complex terrain.
Silver-based I-III-VI-type semiconductor nanocrystals have received extensive attention due to their narrow-band luminescence properties. Herein, we demonstrated a seed-mediated growth of quaternary ...Ag-In-Ga-S (AIGS) nanocrystals (NCs) with narrow-band luminescence. By conducting partial cation exchange with In
3+
and Ga
3+
based on Ag
2
S NCs and controlling the Ag/In feeding ratios (0.25 to 2) of Ag-In-S seeds as well as the inventory of 1-dodecanethiol, we achieved optimized luminescence performance in the synthesized AIGS NCs, characterized by a narrow full width at half maximum of less than 40 nm. Meanwhile, narrow-band luminescent AIGS NCs exhibit a tetragonal AgGaS
2
crystal structure and a gradient alloy structure, rather than a core-shell structure. Most importantly, the kinetics decay curves of time-resolved photoluminescence and the ground state bleaching in transient absorption generally agree with each other regarding the lifetime of the second decay component, which indicates that the narrow-band luminescence is due to the slow radiative recombination between trapped electrons and trapped holes located at the edge of the conduction band and the deep silver-related trap states (
e.g.
, silver vacancy), respectively. This study provides new insights into the correlation between the narrow-band luminescence properties and the structural characteristics of AIGS NCs.
Narrow-band luminescence was observed from Ag-In-Ga-S alloyed nanocrystals were synthesized through a seed-mediated growth and cation exchange strategy, which was originated from the recombination of the conduction band edge to silver vacancy states.
Abrupt drought–flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice ...production. In this study, the response mechanism of yield decline under abrupt drought–flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought–flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought–flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought–flood alteration stress, which are factors that leads to the rice grain yield reduction.
This study aimed to investigate an early diagnostic method for lumbar disc degeneration (LDD) and improve its diagnostic accuracy.
Quantitative biomarkers of the lumbar body (LB) and lumbar discs ...(LDs) were obtained using nuclear magnetic resonance (NMR) detection technology. The diagnostic weights of each biological metabolism indicator were screened using the factor analysis method.
Through factor analysis, common factors such as the LB fat fraction, fat content, and T2* value of LDs were identified as covariates for the diagnostic model for the evaluation of LDD. This model can optimize the accuracy and reliability of LDD diagnosis.
The application of biomarker quantification methods based on NMR detection technology combined with factor analysis provides an effective means for the early diagnosis of LDD, thereby improving diagnostic accuracy and reliability.
Continuous renal replacement therapy (CRRT) is a commonly utilized form of renal replacement therapy (RRT) in the intensive care unit (ICU). A specialized CRRT team (SCT, composed of physicians and ...nurses) engage playing pivotal roles in administering CRRT, but there is paucity of evidence-based research on joint training and management strategies. This study armed to evaluate the knowledge, attitude, and practice (KAP) of ICU staff toward CRRT, and to identify education pathways, needs, and the current status of CRRT implementation.
This study was performed from February 6 to March 20, 2023. A self-made structured questionnaire was used for data collection. Descriptive statistics, T-tests, Analysis of variance (ANOVA), multiple linear regression, and Pearson correlation coefficient tests (α = 0.05) were employed.
A total of 405 ICU staff from 66 hospitals in Central and South China participated in this study, yielding 395 valid questionnaires. The mean knowledge score was 51.46 ± 5.96 (61.8% scored highly). The mean attitude score was 58.71 ± 2.19 (73.9% scored highly). The mean practice score was 18.15 ± 0.98 (85.1% scored highly). Multiple linear regression analysis indicated that gender, age, years of CRRT practice, ICU category, and CRRT specialist panel membership independently affected the knowledge score; Educational level, years of CRRT practice, and CRRT specialist panel membership independently affected the attitude score; Education level and teaching hospital employment independently affected the practice score. The most effective method for ICU staff to undergo training and daily work experience is within the department.
ICU staff exhibit good knowledge, a positive attitude and appropriately practiced CRRT. Extended CRRT practice time in CRRT, further training in a general ICU or teaching hospital, joining a CRRT specialist panel, and upgraded education can improve CRRT professional level. Considering the convenience of training programs will enhance ICU staff participation. Training should focus on basic CRRT principles, liquid management, and alarm handling.
ABSTRACT
The South Asian summer monsoon brings abundant precipitation and associated latent heat release to the south of central Himalaya, and alters hydrothermal conditions of this region. This ...study explored the impact of South Asian summer monsoon on the elevation‐dependence of meteorological variables along the south slope of Mt. Everest in the central Himalaya, which is crucial to modelling the glacio‐hydrological processes in this elevated region. The data were collected at five stations deployed at 2660–5600 m above sea level (asl) along the slope during 2007–2011. Major findings are the following: (1) The amount of precipitation during the monsoon season usually decreases with elevation but it is relatively uniform between 3600 and 5000 m asl. This uniform profile may be attributed to the monsoon–terrain–land interactions, particularly to the retard effect of glacier cooling on daytime upvalley wind; (2) Cloud shielding effects cause lower solar radiation and higher downward longwave radiation in the monsoon than in the other seasons. In particular, higher elevations have more clouds in the afternoon, resulting in an abnormal elevation‐dependence of solar radiation (i.e. higher elevations receive less solar radiation); (3) Strong daytime upvalley wind and moist convection homogenizes the vertical distributions of air mass along the slope, causing a constant lapse rate of both surface air temperature and dew‐point temperature (representing humidity) during typical monsoon months, but this phenomenon is not found in the other seasons. These findings provide critical guidance for extrapolating the meteorological variables from lower to higher elevations in this region.
South Asian summer monsoon greatly affects the elevation‐dependence of meteorological variables along the steepest valley in the world (south of Mt. Everest). Strong daytime upvalley winds and deep convection during the monsoon season cause a uniform precipitation profile between 3500 and 5000 m above sea level, an abnormal elevation‐dependence of solar radiation (higher elevations receive less solar radiation), and a constant vertical gradient of near‐surface air temperature and dew‐point temperature.
Vortex beams' orbital angular momentum (OAM) has important application value in optical communication and other fields. Accurate measurement of their OAM topological charges is required for the ...application of vortex beams in the field of optical communication. As a type of convolutional neural network, DenseNet which combines the "Data Augmentation with Expansion" method, was introduced to measure the fractional topological charge of OAM images in the case of few samples. The OAM images used in this paper generally do not have high brightness, which simulates ultra-long-distance transmission situations in reality. The experiment shows that the classification accuracy of DenseNet network reaches 98.77%, with an average training time of about 1100 seconds, which is short. Our results showcase the potential of convolutional neural network approach to further study the OAM light in the application of free-space optical communication.
The aim of the present work is to isolate a series of triterpene derivatives with rhamnosyl linking acetyl groups from Glechoma longituba according to the structural characteristics of previously ...described triterpene saponins. The extract ion chromatography spectrum of the crude extract of G. longituba was detected and analyzed by HPLC‐HR‐ESI‐MS to determine possible components, and these metabolites were traced and separated by combining high‐resolution mass spectrometry and predicted liquid chromatography retention time. Three 11α, 12α‐epoxypentacyclic oleanolic acid triterpene saponins (glechomanosides H–J) and one ursane triterpene aldehyde saponin with a C‐28 aldehyde group were isolated from G. longituba. The structure of these compounds was confirmed by NMR and compared with those of previously characterized compounds. The strategy described in this report enables a rapid, reliable, and complete analysis of glycoside compounds containing different numbers of acetyl groups at different positions on the sugar.
Nuciferine (NF) has received extensive attention due to its medicinal value in the treatment of metabolic diseases, such as obesity; however, to date, the effects of NF on obesity-related intestinal ...permeability, autophagy and the gut microbiota have not been investigated. Herein, C57BL/6J mice were fed either a chow or a high-fat diet (HFD) with or without NF for 8 weeks. The results showed that NF supplement reduced weight gain, fat accumulation and intestinal permeability in the HFD mice accompanied by improved autophagy. Subsequently, an in vitro experiment was performed using Caco-2 and HT-29 cells, which showed that NF supplement not only promoted the formation of autophagosomes and autophagolysosomes, but also alleviated LPS-increased intestinal permeability. Importantly, NF supplement protected from LPS-induced paracellular permeability impairment after the administration of autophagy-related gene (Atg) 5 small-interfering RNA (siRNA). These results demonstrate that NF exerts beneficial effects on the intestinal permeability by improving autophagy. Furthermore, we also found that NF supplement lowered the abundance of Butyricimonas and increased the abundance of Akkermansia, an anti-obesity bacterium. Thus, overall, we demonstrated that NF supplement confers reduced intestinal permeability by improving autophagy and alters the composition of the gut microbiota in HFD-fed mice, thereby producing an anti-obesity effect.
Low temperature stress is an important abiotic stress for garden roses in northern regions. Two garden rose cultivars ('Dagmar Hastrup' and 'Chandos Beauty') were selected to study the role of ...dehydrin and of carbohydrate metabolism during cold acclimation and deacclimation under the controlled daylength and temperature. The presence of bud dormancy was also observed as this could prevent budburst during warm spells. Both cultivars showed a similar changing pattern of cold acclimation and deacclimation and did not differ in their lowest LT
values.
(
) was up-regulated by low temperatures and not by dehydration stress as the stem water content remained stable during the treatments. Total soluble sugars accumulated with a transient up-regulation of
(a key gene in starch hydrolysis) for 'Dagmar Hastrup' at 2°C and a strong expression under both 2 and -3°C for 'Chandos Beauty'. At 2 and -3°C, raffinose and stachyose strongly accumulated though the up-regulation of
and
differed in the cultivars. Although similar cold hardiness levels were reached, carbohydrate metabolism in response to cold stress is different in the two cultivars. Increasing the temperature after a cold period resulted in fast deacclimation as found by the downregulation of
and
, the decrease of raffinose and stachyose. Bud endodormancy was hardly present in both cultivars.
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