Potential impacts of pandemics on global warming, agricultural production, and biodiversity loss

The rising frequency of infectious diseases under climate change poses an emerging threat to environmental and agricultural sustainability by consuming large quantities of materials. The demand for crops to produce personal protective equipment (PPE) competes for land and fertilizers, leads to cropland expansion, and accelerates climate change, but the ecological impacts remain unclear. Here we explore the impacts of pandemics on global warming, agricultural production, and biodiversity loss in an Earth system model by developing relationships between consumption of PPE and the rate of infection during COVID-19. Meeting the demand for PPE would increase production of cotton lint, corn, and natural rubber, which accelerates global warming by 0.2°C with 1.8% additional species losses by 2100. Our results suggest that the risks of public health, food security, climate change, and ecological integrity have been connected to each other, which should be considered when predicting the impacts of future pandemics

A ocean acidification and oxygen analog device

本实用新型涉及一种海洋酸化和低氧模拟装置，包括气源、空气干燥过滤减压器、备用安全电磁阀、CO2过滤器、干燥过滤器、质量流量控制器、采集控制器、水质传感器、排气阀组。通过pH和溶氧传感器实时监测海水pH和溶氧值，采用双增量式PID控制的方式，调控空气、N2、CO2的曝气比例，以调节海水pH和溶氧水平至设定值并保持稳态。本实用新型可以实时监测并调整气源配比，同步控制海水的pH和溶氧含量，具有稳态精度高、动态响应好、调整时间短等优点，且在有海洋生物呼吸干扰的条件下仍可保持较高的精度

Effect of Current Density on the Composition, Structure and Morphology of Ni W Alloy Electrodeposit

采用分光光度法、X射线衍射和金相显微镜等方法研究在焦磷酸盐体系中，电流密度影响下所获得的nI-W合金电沉积层的组成、结构和表面形态.结果表明，随着电流密度的提高，合金沉积层中的W含量增大；形成置换固溶体的合金沉积层晶格参数涨大、晶格畸变度增大、而显微晶粒尺寸减小；合金沉积层的电结晶生长形态均呈现整齐的团粒状生长特征.讨论了上述实验结果.The effect of current density on the composition, structure and morphology of Ni W alloy electrodeposit obtained in pyrophosphate bath were studied by the methods of spectrophotometry, X ray diffraction and metallurgical microscope.The results show that, by the increment of the cathodic current density,the alloy electrodeposit was formed in displacemental solid solution, and that, with W content raised,lattice parameter expanded,and lattice distortion increased, whereas grain size decreased.All the morphologies of the deposits were presented in neat granular structure in the growth of electrocrystallization.The results were discussed.国家自然科学基

湖泊磷酸酶与微生物活性对内源磷负荷的贡献及其与富营养化的关系

磷酸酶可通过增加磷的生物可利用性促进富营养化过程,在太湖、龙阳湖与莲花湖探讨了这种机制。磷酸酶活性与磷营养水平以及叶绿素a浓度相关。反胶团酶学方法的实验结果表明,溶解态磷酸酶稳定性的不同可能源于酶分子大小、结构与活性基团的差异。太湖微囊藻水华发生处间隙水溶解态磷酸酶在胶团中的活性高且稳定,溶解反应性磷浓度较低,沉积物不同形态磷的含量与好气性细菌数量均低,且呼吸强度明显较高,无机磷与有机磷细菌以及其它微生物均在表层富集,却极少见诸于沉积物。因此,来自酶促水解或其它途径的大量内源磷可能在厌氧状态下经上覆水随

Bioaccumulation and biotransformation of inorganic arsenic in Ruditapes philippinarum

Arsenic (As) is a ubiquitous toxic metalloid, and its toxicity depends greatly on its chemical speciation. Marine mollusks are apt to bioaccumulation of high arsenic contents because of their living habits. In this study, the bioaccumulation and biotransformation of the clam Ruditapes philippinarum were investigated after waterborne exposure to arsenite (As (Ⅲ)) or arsenate (As (Ⅴ)) for 14 days. The results showed that arsenic uptake increased with increasing arsenic concentration in the seawater, while gills of R. philippinarum showed the limited ability to bioaccumulate inorganic arsenic from seawater, with no significant difference compared with control group following waterbone 10 mug/L As (Ⅲ) and As (Ⅴ) exposure for 14 days. The bioavailability of As (Ⅲ) was slightly higher than that of As (Ⅴ) to R. philippinarum, and arsenic was easier to be accumulated in digestive glands. The results demonstrated the As biotransformation in the clams included As (Ⅴ) reduction, As (Ⅲ) oxidation, and methylation. Arsenobetaine (AsB) and dimethylarsinic acid (DMA) was the major arsenic speciation in all treatments, while monomethylarsonic acid (MMA) contents decreased significantly after exposure, indicating that MMA can be quickly metabolized or converted into other arsenic speciation in the rate-limiting conversion reaction of inorganic arsenic. Inorganic arsenic in gills was mainly converted to DMA, but AsB in digestive glands, indicating the different transformation efficiency in different tissues. In summary, the results provided an important basis for elucidating the arsenic bioaccumulation and biotransformation mechanism in R. philippinarum and provided theoretical basis for shellfish breeding and food safety

EB病毒潜伏膜蛋白1介导c-Jun/Jun B异源二聚体对cyclin D1的调节

研究发现LMP1可介导c-Jun/JunB活性异源二聚体的形成,在此基础上,利用建立的Tet-on系统调控LMP1表达的细胞系,采用间接免疫荧光法联合激光共聚焦荧光显徽镜技术、Westernblot方法、荧光素酶活性检测、Super-EMSA方法和流式细胞术,探讨LMP1介导c-Jun/JunB异源二聚体对cyclinD1的调节功能.结果表明,LMP1介导的c-Jun/JunB异源二聚体可上调cyclinD1启动子活性及其表达,并影响细胞周期的行进.国家重点基础研究发展规划(973计划)(批准号:G1998051201) 国家自然科学基金(批准号:30300403,30100005,30000087) 国家杰出青年科学基金(批准号:39525022)资助项

The Memory Effect of MH-Ni Battery

放电深度 (DOD)、放电速率、循环次数对MH Ni电池的记忆效应影响很大 .经过几次全充放循环可以消除记忆效应 .记忆效应的存在与Zn无关 .电池在低DOD循环过程中 ,其放电电位、放电容量一开始下降很快 ,然后逐渐趋于某一值 ,并且放电电流越小 ,相应的最高充电电压越低 .若放电电流增加 ,在随后的第一周充放电过程中最高充电电压迅速增加、放电容量显著小于稳定值 .最后探讨了导致记忆效应的原因 ,并给出了若干消除或减弱记忆效应的设想The memory effect of MH Ni battery was investigated. The depth of discharge, discharge rate and cycle number influence the memory effect greatly. A few completely full charge/discharge cycles could eliminate it. The existence of the memory effect had nothing to do with zinc element. During the course of life cycling at low DOD (degree of discharge),the smaller the discharge current was, the lower was the maximum charge voltage. In addition, discharge voltage and discharge capacity drop fast at the beginning, gradually leveled off at about a value. If the discharge current was increased, the discharge capacity was obviously less than the stabilized value and maximum charge voltage was also changed suddenly. At last, the cause of the memory effect is discussed, and tentative recommendations to eliminate or mitigate the appearance of the memory effect phenomena are given.作者联系地址：浙江大学化学系!浙江杭州310027,浙江大学化学系!浙江杭州310027,浙江大学化学系!浙江杭州310027,浙江大学化学系!浙江杭州310027Author's Address: Dept. of Chem., Zhejiang Univ., Hangzhou City, 310027, Chin

Single and joint acute toxic effects of cadmium and lead on Palaemon carincauda

The presence of heavy metals in the coastal environment has been of great concern due to their non-biodegradable nature. This study aims to investigate single and joint acute toxic effects of Cd~(2+) and Pb~(2+) on Palaemon carincauda and provides the basis for the water quality management of aquaculture. The effects of different concentrations of Cd~(2+) and Pb~(2+) on P. carincauda within 96 h were investigated by using the semistatic acute toxicity test. The results showed the following:(1)The 24, 48, 72 and 96 h median lethal concentrations(LC_(50))of Cd~(2+) on P. carincauda were 138.699, 33.110, 9.719 and 3.650 mg/L, respectively, and the 48, 72 and 96 h LC_(50) of Pb~(2+) were 254.541, 62.750 and 29.074 mg/L, respectively. The 96 h safety concentrations(SC)of Cd~(2+) and Pb~(2+) on P. carincauda were predicted to be 0.365 mg/L and 2.907 mg/L, respectively;(2)At a concentration ratio of 1︰1, the additive index values for Cd~(2+) and Pb~(2+) were 0.155, 0.068, and 0.258 during the experiment time of 48, 72 and 96 h, respectively. These results indicated that Cd~(2+) presented higher toxicity toward the shrimps than Pb~(2+). Joint toxic effects of Cd~(2+) and Pb~(2+) demonstrated synergistic effects during the experimental period.</p