Metallic zinc is an attractive anode material for aqueous rechargeable batteries because of its high theoretical capacity and low cost. However, state-of-the-art zinc anodes suffer from low coulombic ...efficiency and severe dendrite growth during stripping/plating processes, hampering their practical applications. Here we show that eutectic-composition alloying of zinc and aluminum as an effective strategy substantially tackles these irreversibility issues by making use of their lamellar structure, composed of alternating zinc and aluminum nanolamellas. The lamellar nanostructure not only promotes zinc stripping from precursor eutectic Zn
Al
(at%) alloys, but produces core/shell aluminum/aluminum sesquioxide interlamellar nanopatterns in situ to in turn guide subsequent growth of zinc, enabling dendrite-free zinc stripping/plating for more than 2000 h in oxygen-absent aqueous electrolyte. These outstanding electrochemical properties enlist zinc-ion batteries constructed with Zn
Al
alloy anode and K
MnO
cathode to deliver high-density energy at high levels of electrical power and retain 100% capacity after 200 hours.
In this study, Moderate Resolution Imaging Spectroradiometer land cover, land surface temperature (LST), and enhanced vegetation index (EVI) data were used to investigate the trends of surface urban ...heat island intensity (SUHII, urban LST minus rural LST) and their relations with vegetation in 397 global big cities during 2001–2017. Major findings include the following: (1) Annual daytime and nighttime SUHII increased significantly (p < 0.05, Mann‐Kendall trend test) in 42.1% and 30.5% cities, respectively. (2) The daytime SUHII in the growing season was significantly and positively correlated with rural EVI in 58.9% cities. This is because high rural EVI can increase the EVI difference between urban and rural areas. (3) Rural greening contributed 22.5% of the increased daytime SUHII in the growing season at the global scale. This study highlights that the effect of greening in rural areas was a significant and widespread driver for the increased daytime SUHII.
Plain Language Summary
Surface urban heat island (SUHI) refers to higher land surface temperature (LST) in urban than in rural areas. The increased SUHI intensity (urban LST minus rural) was mainly attributed to increased anthropogenic heat emission and built‐up areas and reductions in vegetation in urban areas in the literature. However, this study showed that the increased vegetation (i.e., greening) in rural areas was a significant and widespread driver for the increased daytime SUHI intensity around the world during 2001–2017. The implication of this study is that urban LST may increase much faster than rural LST in future global warming.
Key Points
Annual daytime and nighttime surface urban heat island intensity increased significantly in 42.1% and 30.5% global cities, respectively
Daytime surface urban heat island intensity was significantly and positively correlated with rural enhanced vegetation index in 58.9% cities
At the global scale, the contribution of rural greening to the increased daytime surface urban heat island intensity was 22.5%
AbstractObjectiveTo examine the protective effects of appropriate personal protective equipment for frontline healthcare professionals who provided care for patients with coronavirus disease 2019 ...(covid-19).DesignCross sectional study.SettingFour hospitals in Wuhan, China.Participants420 healthcare professionals (116 doctors and 304 nurses) who were deployed to Wuhan by two affiliated hospitals of Sun Yat-sen University and Nanfang Hospital of Southern Medical University for 6-8 weeks from 24 January to 7 April 2020. These study participants were provided with appropriate personal protective equipment to deliver healthcare to patients admitted to hospital with covid-19 and were involved in aerosol generating procedures. 77 healthcare professionals with no exposure history to covid-19 and 80 patients who had recovered from covid-19 were recruited to verify the accuracy of antibody testing.Main outcome measuresCovid-19 related symptoms (fever, cough, and dyspnoea) and evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, defined as a positive test for virus specific nucleic acids in nasopharyngeal swabs, or a positive test for IgM or IgG antibodies in the serum samples.ResultsThe average age of study participants was 35.8 years and 68.1% (286/420) were women. These study participants worked 4-6 hour shifts for an average of 5.4 days a week; they worked an average of 16.2 hours each week in intensive care units. All 420 study participants had direct contact with patients with covid-19 and performed at least one aerosol generating procedure. During the deployment period in Wuhan, none of the study participants reported covid-19 related symptoms. When the participants returned home, they all tested negative for SARS-CoV-2 specific nucleic acids and IgM or IgG antibodies (95% confidence interval 0.0 to 0.7%).ConclusionBefore a safe and effective vaccine becomes available, healthcare professionals remain susceptible to covid-19. Despite being at high risk of exposure, study participants were appropriately protected and did not contract infection or develop protective immunity against SARS-CoV-2. Healthcare systems must give priority to the procurement and distribution of personal protective equipment, and provide adequate training to healthcare professionals in its use.
There are many studies focusing on spatial variations of surface urban heat islands (SUHIs) in literature. In this study, MODIS land surface temperature (LST) data and China's Land Use/Cover Datasets ...(CLUDs) were used to examine the temporal trends of SUHIs in 31 major Chinese cities during 2001–2015 using three indicators: SUHI intensity (SUHII), area of the SUHI (AreaSUHI) and percentage of area with increasing SUHII (PAISUHII). Correlation analyses between SUHII and background (rural) LST (extracted from MODIS LST), vegetation coverage (reflected by MODIS EVI data) and anthropogenic heat release (reflected by nighttime light data) were performed from temporal rather than spatial perspectives. Our findings showed that the SUHII and AreaSUHI in urbanized areas increased significantly in most cities in summer days, whereas they increased significantly in approximately half and more than half of the cities in summer and winter nights, respectively. In summer days, summer nights and winter nights, the PAISUHII was approximately 80% and over 50% in union areas and the 20km buffer, respectively. Correlation analyses indicated that the SUHII in stable urban areas was negatively correlated with the background LST in summer and winter days for most cities, especially in northern China. A reduction in vegetation contributed to the increasing SUHII in urbanized areas in summer days and nights. The increasing anthropogenic heat release was an important factor for increases in the SUHII in urbanized areas.
Temporal trends of surface urban heat island intensity in China during 2001–2015. SUA: stable urban area. UA: urbanized area. Display omitted
•It is first time to study the temporal trends of SUHI at national scale.•The surface urban heat island is intensifying in China.•SUHII in SUA and UA was correlated with LST and urbanization, respectively.
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome that elevates the risk of hepatocellular carcinoma (HCC). Although alteration of lipid metabolism has ...been increasingly recognized as a hallmark of cancer cells, the deregulated metabolic modulation of HCC cells in the NAFLD progression remains obscure. Here, we discovers an endoplasmic reticulum-residential protein, Nogo-B, as a highly expressed metabolic modulator in both murine and human NAFLD-associated HCCs, which accelerates high-fat, high-carbohydrate diet-induced metabolic dysfunction and tumorigenicity. Mechanistically, CD36-mediated oxLDL uptake triggers CEBPβ expression to directly upregulate Nogo-B, which interacts with ATG5 to promote lipophagy leading to lysophosphatidic acid-enhanced YAP oncogenic activity. This CD36-Nogo-B-YAP pathway consequently reprograms oxLDL metabolism and induces carcinogenetic signaling for NAFLD-associated HCCs. Targeting the Nogo-B pathway may represent a therapeutic strategy for HCC arising from the metabolic syndrome.
The spatial, diurnal and seasonal variations of surface urban heat islands (SUHIs) have been investigated in many places, but we still have limited understanding of the interannual variations of ...SUHIs and associated drivers. In this study, the interannual variations in SUHI intensity (SUHII, derived from MODIS land surface temperature (LST) data (8-day composites of twice-daily observations), urban LST minus rural) and their relationships with climate variability and urbanization were analyzed in 31 cities in China for the period 2001–2015. Significant increasing trends of SUHII were observed in 71.0%, 58.1%, 25.8% and 54.8% the cities in summer days (SDs), summer nights (SNs), winter days (WDs) and winter nights (WNs), respectively. Pearson's correlation analyses were first performed from a temporal perspective, which were different from a spatial perspective as previous studies. The results showed that the SUHII in SDs and WDs was negatively correlated with the background LST and mean air temperature in most of the cities. The nighttime SUHII in most cities was negatively and positively correlated with total precipitation and total sunshine duration, respectively. Average wind speed has little effect on SUHII. Decreasing vegetation and increased population were the main factors that contributed to the increased SUHII in SDs and SNs, while albedo only influenced the SUHII in WDs. In addition, Pearson's correlation analyses across cities showed that cities with higher decreasing rates of vegetation exhibited higher increasing rates of the SUHII in SDs and WDs. Cities with larger population growth rates do not necessarily have higher increasing rates of SUHII.
The temporal trends of SUHII on SDs in the WUA in 31 cities in China. Display omitted
•The interannual variations in surface urban heat island intensity (SUHII) and their relationships with climate variability and urbanization were analyzed.•Decreasing vegetation and increased population in whole urban area were important factors contributing to the increasing SUHII.•The impacts of climate variability on SUHII in the city center depended on time periods and geographical positions.
Objective:
Stroke is a leading cause of mortality and disability. Nicotinamide phosphoribosyltransferase (Nampt) is the rate‐limiting enzyme in mammalian nicotinamide adenine dinucleotide (NAD)+ ...biosynthesis and contributes to cell fate decisions. However, the role of Nampt in brain and stroke remains to be investigated.
Methods:
We used lentivirus‐mediated Nampt overexpression and knockdown to manipulate Nampt expression and explore the effects of Nampt in neuronal survival on ischemic stress both in vivo and in vitro. We also used adenosine monophosphate (AMP)‐activated kinase‐α2 (AMPKα2) and silent mating type information regulation 2 homolog 1 (SIRT1) knockout mice to investigate the underlying mechanisms of Nampt neuroprotection.
Results:
Nampt inhibition by a highly‐specific Nampt inhibitor, FK866, aggravated brain infarction in experimentally cerebral ischemia rats, whereas Nampt overexpression in local brain and Nampt enzymatic product nicotinamide mononucleotide (NMN) reduced ischemia‐induced cerebral injuries. Nampt overexpression and knockdown regulated neuron survival via the AMPK pathway. Neuroprotection of Nampt was abolished in AMPKα2−/− neurons. In neurons, Nampt positively modulated NAD+ levels and thereby controlled SIRT1 activity. SIRT1 coprecipitated with serine/threonine kinase 11 (LKB1), an upstream kinase of AMPK, and promoted LKB1 deacetylation in neurons. Nampt‐induced LKB1 deacetylation and AMPK activation disappeared in SIRT1−/− neurons. In contrast, Ca2+/calmodulin‐dependent protein kinase kinase‐β (CaMKK‐β), another upstream kinase of AMPK, was not involved in the neuroprotection of Nampt. More important, Nampt overexpression‐induced neuroprotection was abolished in SIRT1+/− and AMPKα2−/− mice.
Interpretation:
Our findings reveal that Nampt protects against ischemic stroke through rescuing neurons from death via the SIRT1‐dependent AMPK pathway and indicate that Nampt is a new therapeutic target for stroke. Ann Neurol 2011.
The influences of different data and methods on spatial variations of surface urban heat island intensity (SUHII) in summer days (SDs). A dot represented a city.
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•Influences of ...different data and methods on estimating SUHII were analyzed.•Using nearby suburban will underestimate the variation trends of SUHII.•Ignoring the influences of water body and elevation will influences the SUHII.•The SUHII in SDs monitored by Aqua satellite were higher than Terra satellite.
Few studies have examined the influence of different data and method on estimating the SUHIs. This study aims at analyzing the impact of different method (to define rural area) and different data (MODIS Terra and Aqua satellite data) on estimating the SUHI intensity (SUHII, LST in urban minus rural reference) in 31 cities of China. The major findings include: (1) For SUHII, ignoring the influence of elevation and water body will overestimate the SUHII by 1.68 °C (averaged for 31 cities, hereafter) and 0.28 °C, respectively, in summer days (SDs). Using nearby suburban area as reference will underestimate the SUHII by 1.48 °C in SDs. Different data and method have smaller impact on estimating the SUHII in summer nights (SNs) than in SDs. (2) For spatial variation of SUHII, ignoring the influence of elevation will influence the spatial variation of SUHII in SDs (r = 0.3, p > .05), but other methods have little impact on estimating the spatial variation of SUHII. (3) For interannual variation of SUHII, using nearby suburban area will underestimate the increasing rate of SUHII (SD: 0.106 °C/year, SN: 0.012 °C/year), whereas ignoring the influence of elevation and water body have little influence on the changing rate of SUHII. The changing rates of SUHII in SDs monitored by Terra satellite were 0.025 °C/year lower than Aqua satellite. In all, the present study can enhance our understanding of the influence of different data and method on estimating the SUHII, and provide a useful reference to study the SUHII.
Background/Aims: Acute myocardial infarction (AMI) is one of the leading causes of death in the world. However, specific diagnostic biomarkers have not been fully determined, and candidate regulatory ...targets for AMI have not been identified to date. Long noncoding RNAs (lncRNAs) are a class of RNA molecules that have diverse regulatory functions during embryonic development, normal life, and disease in higher organisms. However, research on the role of lncRNAs in cardiovascular diseases, particularly AMI, is still in its infancy. HOX antisense intergenic RNA (HOTAIR), a 2.2 kb lncRNA, was initially described as a modulator of HOX gene expression. Recent studies have illustrated the important role of HOTAIR in cancer progression, but few studies have reported its function in cardiac disease, including AMI. In the current study, we aimed to detect the expression of HOTAIR during AMI and to explore its function in hypoxia-induced cardiomyocyte injury in neonatal cardiomyocytes. Methods: In 50 consecutively enrolled AMI patients, we examined the serum expression levels of HOTAIR and analysed its correlation with cardiac troponin I (cTnI) expression. Another 50 age- and sex-matched subjects served as healthy controls. Next, the HOTAIR expression was detected in the serum from C57BL/6J mice subjected to coronary artery ligation and in neonatal rat cardiomyocytes induced by hypoxia. Cultured cardiomyocytes apoptosis were measured by terminal deoxynucleotide transferase dUTP nick end labelling (TUNEL) staining. A search for miRNAs that had complementary base paring with HOTAIR was performed utilizing an online software program, and the interaction between miR-1 and HOTAIR was examined using a luciferase reporter assay. Results: Our study revealed that HOTAIR expression was significantly decreased in the serum of AMI patients compared with that of the healthy controls. Similarly, we observed that HOTAIR was downregulated in the serum of mice subjected to coronary artery ligation and in cultured cardiomyocytes exposed to hypoxia. Furthermore, we observed that the adenovirus vector-driven overexpression of HOTAIR dramatically limited hypoxia-induced myocyte apoptosis, whereas knockdown HOTAIR by AdshHOTAIR (adenoviral short hairpin HOTAIR) exhibited the opposite phenotype. Mechanistically, we discovered that the cardioprotective function of HOTAIR is partly based on the negative regulation of miR-1. Conclusions: Taken together, the results of our study suggest that HOTAIR is a protective factor for cardiomyocytes and that the plasma concentration of HOTAIR may serve as a biomarker for human AMI diagnosis.
In this study, the relationships between interannual variations of surface urban heat islands (SUHIs) and climate variability were studied in 31 cities of China for the period 2001–2016. For cold and ...dry Northern China, it was found that the interannual variations of SUHI intensity (SUHII, land surface temperature (LST) in urban minus rural) in urban cores was significantly (p<0.05) and negatively correlated with rural LST in 9 (in summer days (SDs)) and 8 (in winter days (WDs)) of the 15 northern cities, respectively. In addition, the daytime LST differences between hot summers and other summers and between cold winters and other winters were generally lower in urban cores (1.141°C for SDs and 2.535°C for WDs) than in rural areas (1.890°C for SDs and 3.377°C for WDs). The standard deviation was further used to reflect the interannual stabilities of LST, enhanced vegetation index (EVI) and white sky albedo (WSA). Interestingly, the standard deviations of LST across 2001–2016 were generally lower in urban cores (0.994°C for SDs and 1.577°C for WDs) than in rural areas (1.431°C for SDs and 2.077°C for WDs). Similar results were observed for EVI and WSA (winter). The results suggested that the urban surface is less sensitive to climate variability than rural areas in Northern China. Comparatively, most findings were less evident in hot and humid Southern China. Despite the whole world would become warmer or colder in future, the insensitivity of urban surface may mitigate its impacts in cold and dry Northern China. However, it does not mean that urbanization is totally good due to its environmental problem.
The land surface temperature in summer days and winter days in urban cores was more stable than rural in Northern China. Display omitted
•SUHII in summer days and winter days was significantly negatively correlated with background LST•The SUHII generally decreased in hot summers, while increased in cold winters•The standard deviations were used to reflect the interannual stabilities of LST, EVI and WSA•Urban LST, EVI and WSA (in winter) were generally more stable than in rural areas.
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