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Organic small‐molecule fluorophores, characterized by flexible chemical structure and adjustable optical performance, have shown tremendous potential in biosensing. However, classical organic fluorophore motifs feature large overlap between excitation and emission spectra, leading to the requirement of advanced optical set up to filter desired signal, which limits their application in scenarios with simple settings. Here, a series of wavelength‐tunable small‐molecule fluorescent dyes (PTs) bearing simple organic moieties have been developed, which exhibit Stokes shift up to 262 nm, molar extinction coefficients ranged 30,000–100,000 M−1 cm−1, with quantum yields up to 54.8 %. Furthermore, these dyes were formulated into fluorescent nanoparticles (PT‐NPs), and applied in lateral flow assay (LFA). Consequently, limit of detection for SARS‐CoV‐2 nucleocapsid protein reached 20 fM with naked eye, a 100‐fold improvement in sensitivity compared to the pM detection level for colloidal gold‐based LFA. Besides, combined with loop‐mediated isothermal amplification (LAMP), the LFA system achieved the visualization of single copy level nucleic acid detection for monkeypox (Mpox). [ABSTRACT FROM AUTHOR]

Organic small‐molecule fluorophores, characterized by flexible chemical structure and adjustable optical performance, have shown tremendous potential in biosensing. However, classical organic fluorophore motifs feature large overlap between excitation and emission spectra, leading to the requirement of advanced optical set up to filter desired signal, which limits their application in scenarios with simple settings. Here, a series of wavelength‐tunable small‐molecule fluorescent dyes (PTs) bearing simple organic moieties have been developed, which exhibit Stokes shift up to 262 nm, molar extinction coefficients ranged 30,000–100,000 M−1 cm−1, with quantum yields up to 54.8 %. Furthermore, these dyes were formulated into fluorescent nanoparticles (PT‐NPs), and applied in lateral flow assay (LFA). Consequently, limit of detection for SARS‐CoV‐2 nucleocapsid protein reached 20 fM with naked eye, a 100‐fold improvement in sensitivity compared to the pM detection level for colloidal gold‐based LFA. Besides, combined with loop‐mediated isothermal amplification (LAMP), the LFA system achieved the visualization of single copy level nucleic acid detection for monkeypox (Mpox). [ABSTRACT FROM AUTHOR]

Telocytes (TCs) are distinctive interstitial cells due to their characteristic structures and heterogeneity. They are suggested to participate in tissue repair/regeneration. TCs have been identified in many organs of various mammals. However, data on TCs in lower animals are still very limited. In this work, TCs were identified in the myocardium of the bullfrog (Rana catesbeiana) by light and transmission electron microscopy (TEM). The structural relationships between TCs and neighbouring cell types were measured using the ImageJ (FiJi) morphometric software. TCs with slender Tps (telepodes) were located around cardiomyocytes (CMC). TEM revealed TCs with long Tps in the stroma between CMC. The homocellular tight junctions were observed between the Tps. The Tps were also very close to the neighbouring CMC. The distance between Tps and CMC was 0.15 ± 0.08 μm. Notably, Tps were observed to adhere to the periphery of the satellite cells. The Tps and the satellite cells established heterocellular structural connections by tight junctions. Additionally, Tps were frequently observed in close proximity to mast cells (MCs). The distance between the Tps and the MCs was 0.19 ± 0.09 μm. These results confirmed that TCs are present in the myocardium of the bullfrog, and that TCs established structural relationships with neighbouring cell types, including satellite cells and MCs. These findings provide the anatomical evidence to support the note that TCs are involved in tissue regeneration. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID‐19) remains a serious issue, and the role played by meteorological indicators in the process of virus spread has been a topic of academic discussion. Previous studies reached different conclusions due to inconsistent methods, disparate meteorological indicators, and specific time periods or regions. This manuscript is based on seven daily meteorological indicators in the NCEP reanalysis data set and COVID‐19 data repository of Johns Hopkins University from 22 January 2020 to 1 June 2021. Results showed that worldwide average temperature and precipitable water (PW) had the strongest correlation (ρ > 0.9, p < 0.001) with the confirmed COVID‐19 cases per day from 22 January to 31 August 2020. From 22 January to 31 August 2020, positive correlations were observed between the temperature/PW and confirmed COVID‐19 cases/deaths in the northern hemisphere, whereas negative correlations were recorded in the southern hemisphere. From 1 September to 31 December 2020, the opposite results were observed. Correlations were weak throughout the near full year, and weak negative correlations were detected worldwide (|ρ| < 0.4, p ≤ 0.05); the lag time had no obvious effect. As the latitude increased, the temperature and PW of the maximum confirmed COVID‐19 cases/deaths per day generally showed a decreasing trend; the 2020‐year fitting functions of the response latitude pattern were verified by the 2021 data. Meteorological indicators, although not a decisive factor, may influence the virus spread by affecting the virus survival rates and enthusiasm of human activities. The temperature or PW threshold suitable for the spread of COVID‐19 may increase as the latitude decreases. Plain Language Summary: Climate change has altered life's living environment; humans seem to be able to adapt to climate change within a certain range. This adaptability seems to be human talent, but how about a coronavirus? The impact of environmental variables on coronavirus disease (COVID‐19) spread varies between regions. The two meteorological variables that are most likely to affect the distribution of COVID‐19 have significant latitude patterns, which means that in areas with higher climate temperatures, the temperature range for the maximum spread of COVID‐19 is higher, while in areas with lower climate temperatures, the temperature for the maximum spread of COVID‐19 is lower. Perhaps it indicates that the virus also has the ability to adapt to climate change, even more so than humanity. The complete cessation of COVID‐19 pandemic requires everyone's efforts. Key Points: A more than yearlong and global scale analysis showed environmental variables having a possible influence on coronavirus disease (COVID‐19) spreadTemperature and precipitable water had the strongest correlations with COVID‐19 (ρ > 0.9, p < 0.001) than common meteorological indicatorsThe latitude pattern of COVID‐19 may be a key point in the prediction of the next round of its outbreak [ABSTRACT FROM AUTHOR]

Background: Exosomes, internal proteins, lipids, and nucleic acids coated by phospholipid bilayer membranes, are one type of small extracellular vesicles, which can mediate cell-cell communication. In recent years, exosomes have gained considerable scientific interest due to their widely applied prospect in the diagnosis and therapeutics of human and animal diseases. In this study, we describe for the first time a feasible method designed to isolate and characterize exosomes from feline plasma, urine and adipose-derived mesenchymal stem cells. Results: Exosomes from feline plasma, urine and adipose-derived mesenchymal stem cells were successfully isolated by differential centrifugation. Quantification and sizing of exosomes were assessed by transmission electron microscopy, flow nano analysis and western blotting. Detected particles showed the normal size (30–100 nm) and morphology described for exosomes, as well as presence of the transmembrane protein (TSG101, CD9, CD63, and CD81) known as exosomal marker. Conclusions: The results suggest that differential centrifugation is a feasible method for isolation of exosomes from different types of feline samples. Moreover, these exosomes can be used to further diagnosis and therapeutics in veterinary pre-clinical and clinical studies. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stem cells (MSCs) have generated a great amount of interest in recent years as a novel therapeutic application for improving the quality of pet life and helping them free from painful conditions and diseases. It has now become critical to address the challenges related to the safety and efficacy of MSCs expanded in vitro. In this study, we establish a standardized process for manufacture of canine adipose-derived MSCs (AD-MSCs), including tissue sourcing, cell isolation and culture, cryopreservation, thawing and expansion, quality control and testing, and evaluate the safety and efficacy of those cells for clinical applications. Results: After expansion, the viability of AD-MSCs manufactured under our standardized process was above 90 %. Expression of surface markers and differentiation potential was consistent with ISCT standards. Sterility, mycoplasma, and endotoxin tests were consistently negative. AD-MSCs presented normal karyotype, and did not form in vivo tumors. No adverse events were noted in the case treated with intravenously AD-MSCs. Conclusions: Herein we demonstrated the establishment of a feasible bioprocess for manufacturing and banking canine AD-MSCs for veterinary clinical use. [ABSTRACT FROM AUTHOR]

Enrofloxacin, a third-generation fluoroquinolone, is a broad-spectrum antimicrobial drug against a lot of veterinary bacterial diseases. However, bactericidal activity of enrofloxacin is concentration-dependent and its poor aqueous solubility and bitter taste limit its development and application. Meanwhile, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), a widely used cyclodextrin analog, is a safe and an effective drug carrier. It forms inclusion complexes with its drug substrates and improves their physiochemical and pharmacokinetic properties. Enrofloxacin was also found to form a stable inclusion complex with HP-β-CD and different research groups have shown improved solubility for enrofloxacin by 32.5%, 9.25 and 165-fold. Our own efforts in this direction resulted in manifold improvement (916-fold) in its solubility compared to the previous studies. It was further shown that pharmaceutical properties, absorption and bioavailability, of enrofloxacin have also been significantly improved by complexation with HP-β-CD. [ABSTRACT FROM AUTHOR]

Over the last 30 years, there have been several methods developed for the synthesis of oligosaccharides, such as combinatorial synthesis, programmable one‐pot glycosylations, pre‐activation‐based chemo‐selective glycosylation strategy, random glycosylation, chemo‐enzymatic processes, and automated platforms. Distinguishing hydroxyl groups in carbohydrate monomers form the crux of oligosaccharides synthesis. The protection of hydroxyl groups stops glycosylation at undesired positions on carbohydrates, but additional steps are required to install and remove the protecting groups. The targeted functionalization of carbohydrates relies mostly on the protection of hydroxyl groups that are not supposed to undergo glycosylation and to leave the hydroxyl group unprotected where the glycosylation should occur. Numerous procedures to avoid or decrease protecting group manipulations have been developed for the synthesis of a single or an oligosaccharide library, such as glycosylation on unprotected or partially protected acceptors, and random glycosylation on unprotected acceptors. In this review, overall approaches for glycosylation on unprotected or partially protected acceptors in the synthesis of oligosaccharides and oligosaccharide libraries are summarized, the glycosylation on unprotected or partially protected carbohydrate acceptors with or without tin or boron mediation, and random glycosylation on unprotected or partially protected acceptors in solution phase or on solid phase are discussed. [ABSTRACT FROM AUTHOR]

Recent studies have reported that T-reg cells are intimately linked with hair follicles in a stage-dependent manner and play an important role in hair follicle cycling and regeneration in murine skin. Further study revealed that T-reg cell's regulation of hair follicle growth is through its preferential expression of the Notch ligand Jagged‐1 (Jag1), which facilitates hair follicle regeneration. However, the role of Jag1 in androgen-suppressed hair growth is yet to be investigated. In addition, although epidermal growth factor (EGF) is a mitogen for cells including skin cells, whether it works synergistically with Jag1 to enhance hair follicle development is unknown. The current study intended to investigate effects of topical application of Jag1 on androgen-suppressed hair growth, and to determine the potential synergistic effect of EGF and Jag1 in this process in vivo. Fifty mice were depilated at the dorsal back area to achieve synchronized anagen development, and randomly divided into five groups with the following topical treatments control for 14 days; testosterone to induce androgenetic alopecia; Jagged1 (testosterone + Jagged1); EGF (testosterone + EGF); and Jagged1 + EGF (testosterone + Jagged1 + EGF). It was found that EGF and Jag1 by itself respectively, did not promote androgen-suppressed hair growth significantly. This stimulating effect was enhanced in the presence of both EGF and Jagged1 (p < 0.05). The hair growth promoting effect was accompanied by better follicle growth, which is associated with increased cell proliferation in the hair follicle and altered the expression of genes that are important in hair follicular cell proliferation and differentiation. Our results provide insights into the therapeutic potential of these peptides for androgenetic alopecia. [ABSTRACT FROM AUTHOR]

The Weather Research and Forecasting (WRF) model was employed to simulate the water and energy process over the near surface in the Yellow River source region from July to September 2015. The Rapid Update Cycle (RUC), Noah, Noah-Multi-Physics (Noah-MP), and Community Land Model (CLM) version 4 land surface schemes were selected and evaluated in our experiments. The simulated results were also compared with the Global Land Data Assimilation System (GLDAS) outputs, the ground-based automatic weather stations (AWSs), and the Zoige plateau wetlands ecosystem research flux station data. There was substantial agreement between the results of the simulations and observations in terms of 2-m temperature and relative humidity. However, the simulated values of the 2-m temperature were mostly lower than observations, while the values of relative humidity were higher than the observations. The correlation coefficients (R) between the simulations and observations of air temperature in four experiments were all higher than 0.94, and simulated results of the WRF-RUC experiment had the minimum bias compared with other experiments. The root mean square error (RMSE) and bias of 2-m relative humidity between the WRF-CLM4 simulations and observations were lower than other experiments. Moreover, the simulation of the 10-cm soil temperature was lower than the observations. WRF-CLM4 simulations agreed better with the observations, and WRF-Noah-MP simulations had the largest bias in all of the experiments. The soil moisture increased rapidly when precipitation was occurring and decreased slowly after the precipitation. The four experiments overestimate precipitation leading to higher soil moisture compared with the real situations. The peak value of net radiation was appropriately 850 W/m2 during the summertime in the Zoige plateau area. The simulated net radiation agreed well with the observation except in the WRF-RUC scheme. During the summertime, vegetation grew rapidly, and the latent heat flux transport increased and played a dominant role in surface energy transport in the Zoige area. The RMSE between the simulation and observation of latent heat flux had the minimum value of 98.0 W/m2 in the WRF-CLM4 scheme, and the bias of sensible heat flux had the minimum value of 15.4 W/m2 in the WRF-Noah scheme. This study used the WRF model to explore the applicability of the different land surface schemes in the Zoige plateau area. The research related to this study can be used to understand the water-energy cycle process over the Qinghai-Tibet Plateau wetland and can also provide references for the application of regional meteorological models over this area. [ABSTRACT FROM AUTHOR]

Fondaparinux (trade name Arixtra) is a safe and efficacious anticoagulant, and it is chemically related to low-molecular-weight heparins such as enoxaparin. Fondaparinux is a synthetic pentasaccharide, and its synthesis is difficult and expensive. The high cost of fondaparinux thwarts its extensive worldwide usage. Over the last two decades, several research groups and pharmaceutical companies have been interested in finding efficient and practical methods for its synthesis. The present review discusses those strategies and their pros and cons in a comparative account. [ABSTRACT FROM AUTHOR]

To study the land surface and atmospheric meteorological characteristics of non-uniform underlying surfaces in the semi-arid area of Northeast China, we use a “High-Resolution Assimilation Dataset of the water-energy cycle in China (HRADC)”. The grid points of three different underlying surfaces were selected, and their meteorological elements were averaged for each type (i.e., mixed forest, grassland, and cropland). For 2009, we compared and analyzed the different components of leaf area index (LAI), soil temperature and moisture, surface albedo, precipitation, and surface energy for various underlying surfaces in Northeast China. The results indicated that the LAI of mixed forest and cropland during the summer is greater than 5 m2 m−2 and below 2.5 m2 m−2 for grassland; in the winter and spring seasons, the Green Vegetation Fraction (GVF) is below 30%. The soil temperature and moisture both vary greatly. Throughout the year, the mixed forest is dominated by latent heat evaporation; in grasslands and croplands, the sensible heat flux and the latent heat flux are approximately equal, and the GVF contributed more to latent heat flux than sensible heat flux in the summer. This study compares meteorological characteristics between three different underlying surfaces of the semi-arid area of Northeast China and makes up for the insufficiency of purely using observations for the study. This research is important for understanding the water-energy cycle and transport in the semi-arid area. [ABSTRACT FROM AUTHOR]

To better understand how severe storms form and evolve in the outer rainbands of typhoons, in this study, we investigate the evolutionary characteristics and possible formation mechanisms for severe storms in the rainbands of Typhoon Mujigae, which occurred during 2-5 October 2015, based on the NCEP-NCAR reanalysis data, conventional observations, and Doppler radar data. For the rainbands far from the inner core (eye and eyewall) of Mujigae (distance of approximately 70-800 km), wind speed first increased with the radius expanding from the inner core, and then decreased as the radius continued to expand. The Rankine Vortex Model was used to explore such variations in wind speed. The areas of strong stormy rainbands were mainly located in the northeast quadrant of Mujigae, and overlapped with the areas of high winds within approximately 300-550 km away from the inner core, where the strong winds were conducive to the development of strong storms. A severe convective cell in the rainbands developed into waterspout at approximately 500 km to the northeast of the inner core, when Mujigae was strengthening before it made landfall. Two severe convective cells in the rainbands developed into two tornadoes at approximately 350 km to the northeast of the inner core after Mujigae made landfall. The radar echo bands enhanced to 60 dBZ when mesocyclones occurred in the rainbands and induced tornadoes. The radar echoes gradually weakened after the mesocyclones weakened. The tops of parent clouds of the mesocyclones elevated at first, and then suddenly dropped about 20 min before the tornadoes appeared. Thereby, the cloud top variation has the potential to be used as an early warning of tornado occurrence. [ABSTRACT FROM AUTHOR]

In this paper, the NCEP-NCAR daily reanalysis data are used to investigate the characteristics of the atmospheric heat source/sink (AHSS) over South Asia (SA) and southern Indian Ocean (SIO). The thermal differences between these two regions and their influence on the outbreak of the Indian summer monsoon (ISM) are explored. Composite analysis and correlation analysis are applied. The results indicate that the intraseasonal variability of AHSS is significant in SA but insignificant in the SIO. Large inland areas in the Northern Hemisphere still behave as a heat sink in March, similar to the situation in winter. Significant differences are found in the distribution of AHSS between the ocean and land, with distinct land-ocean thermal contrast in April, and the pattern presents in the transitional period right before the ISM onset. In May, strong heat centers appear over the areas from the Indochina Peninsula to the Bay of Bengal and south of the Tibetan Plateau (TP), which is a typical pattern of AHSS distribution during the monsoon season. The timing of SA-SIO thermal difference turning positive is about 15 pentads in advance of the onset of the ISM. Then, after the thermal differences have turned positive, a pre-monsoon meridional circulation cell develops due to the near-surface heat center and the negative thermal contrast center, after which the meridional circulation of the ISM gradually establishes. In years of early (late) conversion of the SA-SIO thermal difference turning from negative to positive, the AHSS at all levels over the TP and SIO converts later (earlier) than normal and the establishment of the ascending and descending branches of the ISM's meridional circulation is later (earlier) too. Meanwhile, the establishment of the South Asian high over the TP is later (earlier) than normal and the conversion of the Mascarene high from winter to summer mode occurs anomalously late (early). As a result, the onset of the ISM is later (earlier) than normal. However, the difference in vorticity between early and late conversion only shows in the changes of strong vorticity centers' location in the upper and lower troposphere. [ABSTRACT FROM AUTHOR]

The high ridge in the northern branch of the subtropical westerly (hereafter referred to as northern branch ridge) extends from the north of the Tibetan Plateau to the north of Barr Kashmir Lake (32.5 °-47.5 ° N, 70 °-95 ° E) during wintertime. The intensity index and zonal position index of the wintertime northern branch ridge (WNBR) are defined in this study by using the NCEP-NCAR reanalysis data and precipitation and temperature observations at 160 stations in China. Interannual variation features of the WNBR and its relation with precipitation and surface air temperature in China are discussed based on wavelet analysis, correlation analysis, and composite analysis. The results indicate that the intensity and zonal position of the WNBR exhibit significant interannual variability. The intensity of the WNBR gradually weakens and varies in periodic cycles of 4-6, quasi-2, and quasi-16 yr. Its zonal position shifts westward slightly and varies in periodic cycles of quasi-8 and quasi-16 yr. The WNBR is highly correlated with precipitation and surface air temperature in China. When the WNBR is strong (weak) and its zonal position shifts eastward (westward), winter precipitation in Northeast China and the northern region of Northwest China increases (decreases), whereas precipitation decreases in central China, South China, and eastern regions of Northwest and Southwest China. Meanwhile, surface air temperatures in most areas of China are higher (lower) than normal. Further investigation has revealed that the two indexes are closely related to variations in general atmospheric circulation, which explains why there exists a close linkage between the variation of the WNBR and climate in China. It is believed that the WNBR is also tied to the Rossby wave, the North Atlantic Oscillation, the East Asian trough, and the North Pacific jet stream. [ABSTRACT FROM AUTHOR]

Cholic acid and galactose or lactose dual conjugated chitosan derivatives were designed and synthesized as potential anti liver cancer drug carriers, their structures were characterized through proton NMR spectra, elemental analysis, size distribution, zeta potential, and scanning electron microscope image studies. The ability of the dual conjugates to enhance the aqueous solubility of the cancer drug sorafenib was evaluated. The entrapment efficiency (EE%) and drug content (DC%) of sorafenib in the inclusion complexes were measured. The chitosan dual conjugate with cholic acid and galactose was found to be best in enhancing the aqueous solubility of sorafenib. The solubility of sorafenib in water has increased from 1.7 µg/mL to 1900 µg/mL which is equal to 1117-fold increase in its solubility due to the inclusion complex with chitosan conjugate. [ABSTRACT FROM AUTHOR]

Precipitation microphysics over the Tibetan Plateau (TP) remain insufficiently understood, due to the lack of observations and studies. This paper presents a comprehensive investigation of the raindrop size distribution (DSD) for rainfall that happened on the eastern slope of TP in summer. DSD differences between different rain types and under different rain rates are investigated. Confidential empirical relationships between the gamma shape and slope parameters, and between reflectivity and rain rate are proposed. DSD properties in this area are also compared with those in other areas. The results indicate that the stratiform and convective rains contribute to different rain duration and amount, with diverse rainfall macro- and microphysical properties. The rain spectra of two rain types can become broader with higher concentrations as the rain rate increases. DSDs in this area are different to those in other areas. The stratiform DSD is narrower than that in the non-plateau area. The two rain types of this area both have higher number concentrations for 0.437–1.625 mm raindrops than those of the mid-TP. The relationships of shape–slope parameters and reflectivity–rain rate in this area are also different from those in other areas. The rain spectra in this area can produce a larger slope parameter under the same shape parameter than in the mid-TP. The convective rain can produce a smaller rain rate under the same reflectivity. The accuracy proposed reflectivity–rain rate relationship in application to quantitative rainfall estimation is also discussed. The results show that the relationship has an excellent performance when the rain rate exceeds 1 mm h−1. [ABSTRACT FROM AUTHOR]