Background: COVID-19 is a highly infectious respiratory disease. No therapeutics have yet been proven effective for treating severe COVID-19. Objectives: To determine whether human umbilical cord mesenchymal stem cell infusion may be effective and safe for the treatment of severe COVID-19. Methods: Patients with severe COVID-19 were randomly divided into 2 groups: the standard treatment group and the standard treatment plus hUC-MSC infusion group. The incidence of progression from severe to critical illness, 28-day mortality, clinical symptom improvement, time to clinical symptom improvement, hematologic indicators including C-reactive protein, lymphocyte number, and interleukin 6, and imaging changes were observed and compared between the two groups. Measurements and main results: The incidence of progression from severe to critical illness and the 28-day mortality rate were 0 in the hUC-MSC treatment group, while 4 patients in the control group deteriorated to critical condition and received invasive ventilation; 3 of them died, and the 28-day mortality rate was 10.34%. In the hUC-MSC treatment group, the time to clinical improvement was shorter than that in the control group. Clinical symptoms of weakness and fatigue, shortness of breath, and low oxygen saturation obviously improved beginning on the third day of stem cell infusion and reached a significant difference on day 7. CRP and IL-6 levels were significantly lower from day 3 of infusion, the time for the lymphocyte count to return to the normal range was significantly faster, and lung inflammation absorption was significantly shorter on CT imaging in the hUC-MSC group than in the control group. Conclusions: Intravenous transplantation of hUC-MSCs is a safe and effective method that can be considered a salvage and priority treatment option for severe COVID-19.

This study draws upon social cognitive career theory and higher education literature to test a conceptual framework for understanding the entrance into science, technology, engineering, and mathematics (STEM) majors by recent high school graduates attending 4-year institutions. Results suggest that choosing a STEM major is directly influenced by intent to major in STEM, high school math achievement, and initial postsecondary experiences, such as academic interaction and financial aid receipt. Exerting the largest impact on STEM entrance, intent to major in STEM is directly affected by 12th-grade math achievement, exposure to math and science courses, and math self-efficacy beliefs—all three subject to the influence of early achievement in and attitudes toward math. Multiple-group structural equation modeling analyses indicated heterogeneous effects of math achievement and exposure to math and science across racial groups, with their positive impact on STEM intent accruing most to White students and least to underrepresented minority students.

This paper raises the question and provides empirical evidence regarding the status of the evolution of the state‐owned enterprises (SOEs) in China today. In this study, we compare the SOEs to domestic private‐owned enterprises (POEs) and foreign‐controlled businesses (FCBs) in the context of their organizational cultures. While a new ownership form, many of the POEs evolved from former collectives that reflect the traditional values of Chinese business. Conversely, the FCBs are much more indicative of the large global MNCs. Therefore, we look at the SOEs in the context of these two reference points. We conclude that the SOEs of today have substantially transformed to approximate a configuration desired by the Chinese government when it began the SOE transformation a couple of decades ago to make them globally competitive. The SOEs of today appear to be appropriately described as China's economic dynamic dynamo for the future. Copyright © 2006 John Wiley & Sons, Ltd.

Immediate hemorrhage control and anti-infection play important roles in the wound management. Besides, a moist environment is also beneficial for wound healing. Hydrogels are promising materials in urgent hemostasis and drug release. However, hydrogels have the disadvantage of rapid release profiles, leading to the exposure to high drug concentrations. In this study, we constructed hybrid hydrogels with rapid hemostasis and sustainable antibacterial property combining aminoethyl methacrylate hyaluronic acid (HA-AEMA) and methacrylated methoxy polyethylene glycol (mPEG-MA) hybrid hydrogels and chlorhexidine diacetate (CHX)-loaded nanogels. The CHX-loaded nanogels (CLNs) were prepared by the enzyme degradation of CHX-loaded lysine-based hydrogels. The HA-AEMA and mPEG-MA hybrid hydrogel loaded with CLNs (labeled as Gel@CLN) displayed a three-dimensional microporous structure and exhibited excellent swelling, mechanical property, and low cytotoxicity. The Gel@CLN hydrogel showed a prolonged release period of CHX over 240 h and the antibacterial property over 10 days. The hemostasis and wound-healing properties were evaluated in vivo using a mouse model. The results showed that hydrogel had the rapid hemostasis capacity and accelerated wound healing. In summary, CLN-loaded hydrogels may be excellent candidates as hemostasis and anti-infection materials for the wound dressing application.

Mosquitoes transmit devastating human diseases because they need vertebrate blood for egg development. Metabolism in female mosquitoes is tightly coupled with blood meal-mediated reproduction, which requires an extremely high level of energy consumption. Functional analysis has shown that major genes encoding for enzymes involved in lipid metabolism (LM) in the mosquito fat bodies are down-regulated at the end of the juvenile hormone (JH)-controlled posteclosion (PE) phase but exhibit significant elevation in their transcript levels during the post-blood meal phase (PBM), which is regulated mainly by 20-hydroxyecdysone (20E). Reductions in the transcript levels of genes encoding triacylglycerol (TAG) catabolism and β-oxidation enzymes were observed to correlate with a dramatic accumulation of lipids in the PE phase; in contrast, these transcripts were elevated significantly and lipid stores were diminished during the PBM phase. The RNAi depletion of Methoprene-tolerant (Met) and ecdysone receptor (EcR), receptors for JH and 20E, respectively, reversed the LM gene expression and the levels of lipid stores and metabolites, demonstrating the critical roles of these hormones in LM regulation. Hepatocyte nuclear factor 4 (HNF4) RNAi-silenced mosquitoes exhibited down-regulation of the gene transcripts encoding TAG catabolism and β-oxidation enzymes and an inability to use lipids effectively, as manifested by TAG accumulation. The luciferase reporter assay showed direct regulation of LM-related genes by HNF4. Moreover, gene expression was down-regulated by Met and activated by EcR and Target of rapamycin, providing a link between nutritional and hormonal regulation of LM in female mosquitoes.

Hematophagous mosquitoes serve as vectors of multiple devastating human diseases, and many unique physiological features contribute to the incredible evolutionary success of these insects. These functions place high-energy demands on a reproducing female mosquito, and carbohydrate metabolism (CM) must be synchronized with these needs. Functional analysis of metabolic gene profiling showed that major CM pathways, including glycolysis, glycogen and sugar metabolism, and citrate cycle, are dramatically repressed at post eclosion (PE) stage in mosquito fat body followed by a sharply increase at post-blood meal (PBM) stage, which were also verified by Real-time RT-PCR. Consistent to the change of transcript and protein level of CM genes, the level of glycogen, glucose and trehalose and other secondary metabolites are also periodically accumulated and degraded during the reproductive cycle respectively. Levels of triacylglycerols (TAG), which represent another important energy storage form in the mosquito fat body, followed a similar tendency. On the other hand, ATP, which is generated by catabolism of these secondary metabolites, showed an opposite trend. Additionally, we used RNA interference studies for the juvenile hormone and ecdysone receptors, Met and EcR, coupled with transcriptomics and metabolomics analyses to show that these hormone receptors function as major regulatory switches coordinating CM with the differing energy requirements of the female mosquito throughout its reproductive cycle. Our study demonstrates how, by metabolic reprogramming, a multicellular organism adapts to drastic and rapid functional changes.

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T he ChAllenge. Climate and weather forecasting applications share a common ancestry and build on the same physical principles. Nevertheless, climate research and numerical weather prediction (NWP) are commonly seen as different disciplines. The emerging concept of "seamless prediction" forges weather forecasting and climate change studies into a single framework. At the same