COVID-19 causes record decline in global CO2 emissions

The considerable cessation of human activities during the COVID-19 pandemic has affected global energy use and CO2 emissions. Here we show the unprecedented decrease in global fossil CO2 emissions from January to April 2020 was of 7.8% (938 Mt CO2 with a +6.8% of 2-{\sigma} uncertainty) when compared with the period last year. In addition other emerging estimates of COVID impacts based on monthly energy supply or estimated parameters, this study contributes to another step that constructed the near-real-time daily CO2 emission inventories based on activity from power generation (for 29 countries), industry (for 73 countries), road transportation (for 406 cities), aviation and maritime transportation and commercial and residential sectors emissions (for 206 countries). The estimates distinguished the decline of CO2 due to COVID-19 from the daily, weekly and seasonal variations as well as the holiday events. The COVID-related decreases in CO2 emissions in road transportation (340.4 Mt CO2, -15.5%), power (292.5 Mt CO2, -6.4% compared to 2019), industry (136.2 Mt CO2, -4.4%), aviation (92.8 Mt CO2, -28.9%), residential (43.4 Mt CO2, -2.7%), and international shipping (35.9Mt CO2, -15%). Regionally, decreases in China were the largest and earliest (234.5 Mt CO2,-6.9%), followed by Europe (EU-27 & UK) (138.3 Mt CO2, -12.0%) and the U.S. (162.4 Mt CO2, -9.5%). The declines of CO2 are consistent with regional nitrogen oxides concentrations observed by satellites and ground-based networks, but the calculated signal of emissions decreases (about 1Gt CO2) will have little impacts (less than 0.13ppm by April 30, 2020) on the overserved global CO2 concertation. However, with observed fast CO2 recovery in China and partial re-opening globally, our findings suggest the longer-term effects on CO2 emissions are unknown and should be carefully monitored using multiple measures

Comparative Analysis of Microstructure and Physicochemical Properties of Sweetpotato (Ipomoea batatas (L.) Lam) Starch

To explore and make use of the properties of sweetpotato starch (Luoshu), the particle morphology, particle size, ordered structure, lamella structure, amylose content, amylopectin chain length distribution, degree of branching, thermal, pasting and rheological properties of sweetpotato starch were analyzed. Furthermore, the correlations between their microstructure and physicochemical properties were also studied using correlation analysis. The starch granules were round spherical, round-like, oval, hemispherical, and angled polyhedral shapes, and the median diameter range was 15.01~18.40 μm. The pasting pattern of the sweetpotato starch was "from the central umbilical point of the starch granule to the surface", and the main fragments of amylopectin were short chains, with fa and fb1 chains accounting for 76.27%~79.22%. Luoshu 9 and Luoshu 10 had high peak viscosity and swelling power. Luoshu 11 had low breakdown value, high storage modulus and loss modulus. Luoshu 12 exhibited the lowest setback value and was difficult to retrogradation. Luoshu 14 had good thermal stability and elasticity. Luoshu 16 had the highest amylose content and setback value. Therefore, Luoshu 9 and Luoshu 10 could be used as thickeners, Luoshu 11 was suitable for baked foods, Luoshu 12 was suitable for frozen products, Luoshu 14 could be used as raw materials for jelly, and Luoshu 16 was suitable for starch noodle processing. In addition, particle size, molecular structure of amylose and amylopectin, short-range order degree were the key factors affecting the thermal stability, pasting and gel properties of sweetpotato starch. A significant correlation was observed between the microstructure and physicochemical properties of starch made from different varieties of sweetpotatoes, thus providing a basis for the processing and utilization of sweetpotato starch as well as sweetpotato breeding

Comparison of HBV-specific T cell reactivity across the pregnant, postpartum and non-pregnant women with chronic HBV infection

ObjectiveTo investigate the features of HBV-specific T cell reactivity across the pregnant, postpartum or non-pregnant women with chronic HBV infection.MethodsA total of 283 patients with chronic HBV infection were enrolled in this study, including 129 patients during pregnancy, 58 patients during postpartum less than 6 months and 96 non-pregnant patients at childbearing age. A universal ELISpot assay was set up using a broad-spectrum T-cell epitope peptide library which containing 103 functionally validated CD8+ T-cell epitopes derived from overall HBsAg, HBc/eAg, HBx and HBpol proteins and fitting to the human leukocyte antigen polymorphisms of Chinese population. Then, The functional HBV-specific T cells in peripheral blood were detected.ResultsThe spot-forming units (SFUs) of HBV-specific T cells in the pregnant group showed no statistical difference from the postpartum group, but significantly less than that in the non-pregnant group (p = 0.046). In the untreated patients, the pregnant group displayed HBe/cAg-specific T cells (SFUs) less than the non-pregnant group (P = 0.025) and the postpartum group (P = 0.045). Meanwhile, in the NUCs-treated patients, the three groups presented similar HBV-specific T cell reactivity. Furthermore, the SFUs in the NUCs-treated pregnant group were similar to that in the NUCs-untreated pregnant group. Importantly, ROC analysis demonstrated that the HBV-specific T cells (SFUs) (AUC = 0.742) and combined with HBsAg levels (AUC = 0.775) or with HBeAg level (AUC = 0.78) had a good predictive performance for hepatitis progression during pregnancy group.ConclusionPregnancy can reduce HBV-specific T cell reactivity in the women with chronic HBV infection, and NUCs treatment cannot improve their HBV-specific T cells reactivity. Routine monitoring of HBV-specific T cells during pregnant and postpartum period can provide precise evaluation for immune function and valuable guidance for treatments

Development of a live attenuated vaccine candidate for equid alphaherpesvirus 1 control: a step towards efficient protection

Equid alphaherpesvirus 1 (EqAHV1) is a viral pathogen known to cause respiratory disease, neurologic syndromes, and abortion storms in horses. Currently, there are no vaccines that provide complete protection against EqAHV1. Marker vaccines and the differentiation of infected and vaccinated animals (DIVA) strategy are effective for preventing and controlling outbreaks but have not been used for the prevention of EqAHV1 infection. Glycoprotein 2 (gp2), located on the envelope of viruses (EqAHV1), exhibits high antigenicity and functions as a molecular marker for DIVA. In this study, a series of EqAHV1 mutants with deletion of gp2 along with other virulence genes (TK, UL24/TK, gI/gE) were engineered. The mutant viruses were studied in vitro and then in an in vivo experiment using Golden Syrian hamsters to assess the extent of viral attenuation and the immune response elicited by the mutant viruses in comparison to the wild-type (WT) virus. Compared with the WT strain, the YM2019 Δgp2, ΔTK/gp2, and ΔUL24/TK/gp2 strains exhibited reduced growth in RK-13 cells, while the ΔgI/gE/gp2 strain exhibited significantly impaired proliferation. The YM2019 Δgp2 strain induced clinical signs and mortality in hamsters. In contrast, the YM2019 ΔTK/gp2 and ΔUL24/TK/gp2 variants displayed diminished pathogenicity, causing no observable clinical signs or fatalities. Immunization with nasal vaccines containing YM2019 ΔTK/gp2 and ΔUL24/TK/gp2 elicited a robust immune response in hamsters. In particular, compared with the vaccine containing the ΔTK/gp2 strain, the vaccine containing the ΔUL24/TK/gp2 strain demonstrated enhanced immune protection upon challenge with the WT virus. Furthermore, an ELISA for gp2 was established and refined to accurately differentiate between infected and vaccinated animals. These results confirm that the ΔUL24/TK/gp2 strain is a safe and effective live attenuated vaccine candidate for controlling EqAHV1 infection

Oligo/Amenorrhea Is an Independent Risk Factor Associated With Low Ovarian Response

CapsuleOligo/amenorrhea is an independent risk factor of low ovarian response but not high ovarian response, particularly in women with low AMH levels.ObjectiveTo investigate the association of menstrual cycle length (MCL) with anti-Müllerian hormone (AMH) and ovarian response.MethodsThis was a retrospective cohort study. A total of 7471 women who underwent ovarian stimulation and oocyte retrieval were enrolled. The main outcome was the number of oocytes retrieved.Main ResultsA total of 5734 patients were eligible for analysis. In women without polycystic ovary syndrome (PCOS), serum AMH levels and antral follicle count were significantly lower in women with short cycles and higher in women with oligo/amenorrhea than those with a normal menstrual cycle. In women with PCOS, compared to women with a normal menstrual cycle, women with short cycles and women with oligo/amenorrhea showed higher antral follicle count and higher serum AMH levels. Compared with the 0-25th range group of AMH levels, 75-100th percentile groups showed a significantly increased rate of oligo/amenorrhea in women with and without PCOS [adjusted odds ratio (OR) =1.9 (1.04, 3.46), 2.4 (1.70, 3.35)]. In women without PCOS, the low ovarian response was more common in women with short cycles and less common in women with oligo/amenorrhea compared to women with normal cycles [OR=3.0 (2.38, 3.78), 0.7 (0.55, 0.96), respectively]. When adjusted for AMH levels, both short cycles and oligo/amenorrhea were associated with an increased risk of low response [adjusted OR=1.3 (1.02, 1.75), 1.3 (0.93, 1.86), respectively]. In women without PCOS and with low AMH levels, the low ovarian response was more common in women with short cycles as well as in women with oligo/amenorrhea [OR=1.5 (1.08, 1.98), 1.7 (1.08, 2.69), adjusted OR=1.2 (0.86, 1.74), 2.2 (1.31, 3.82), respectively].ConclusionAMH levels are significantly associated with increased risk of oligo/amenorrhea in women with and without PCOS. AMH is an indispensable confounder in the association between MCL and ovarian response in women without PCOS. Oligo/amenorrhea is an independent risk factor associated with a low ovarian response in women without PCOS, particularly those with low AMH levels

Establishment and application of a TaqMan-based quantitative PCR assay for simultaneous detection of bovine Brucella spp. and Mycobacterium spp.

Brucellosis and tuberculosis are two zoonotic, chronic infectious diseases caused by bacteria of the genus Brucella and Mycobacterium, respectively, which pose significant hazards to both animal husbandry and human health. Currently, mixed infections of these two pathogens are prevalent in livestock production; thus, establishing a molecular diagnostic method for the simultaneous detection and analysis of brucellosis and tuberculosis is crucial for the prevention and control of these diseases. By utilizing conserved regions within the genomes of Brucella and Mycobacterium, we designed specific primers and probes. After optimizing the developed qPCR assay conditions, we determined the lower limit of detection to be ten copies/ μL. Cross-testing with other bovine-derived pathogens demonstrated no cross-reactivity. Repeatability tests indicated that the coefficient of variation for the developed qPCR assay was less than 4.10% both within and between batches. We employed both the developed qPCR assay and a commercial qPCR assay to analyze sixty mixed infection samples of Brucella and Mycobacterium from various regions. The results revealed positivity rates of 100% and 96.67% for Brucella, and 100% and 95.00% for Mycobacterium, respectively. These findings indicate that a highly sensitive, specific, reproducible, and versatile qPCR method has been developed for the simultaneous quantitative detection of Brucella and Mycobacterium, which can be applied in studying the pathogenesis and epidemiology of these pathogens

Near-real-time monitoring of global CO2 emissions reveals the effects of the COVID-19 pandemic

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO2 emissions (−1551 Mt CO2) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic’s effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially

Near-real-time monitoring of global CO₂ emissions reveals the effects of the COVID-19 pandemic

The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO₂) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO₂ emissions (−1551 Mt CO₂) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic’s effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially

Political Resource Curse under Authoritarianism: Evidence from China *

Abstract By analyzing a panel constructed on the political turnovers of 4,390 county leaders in China during 1999-2008, we find that the revenue windfalls accrued to these officials from land sales since 1998 have both undermined the effectiveness of the promotion system for government officials and fueled corruption. Instead of rewarding efforts made to boost GDP growth, promotion is now also positively correlated with signaling efforts or specifically increased spending on flamboyant (so-called "image") public projects, with those politically connected to their superiors and those who are beyond the prime age for promotion being the primary beneficiaries. Likewise, the same revenue windfalls have also led to corruption, as gauged from the increases in the government workforce and administrative expenditure but not social welfare spending. Our findings highlight how land revenue windfalls can lead to a political resource curse in a highly politically centralized authoritarian regime