关于食用菌基质菌丝代谢及其质内环境改良的研究

食用菌基质菌丝分解代谢与呼吸过程产生酸性物质和引起基质氧气缺乏,在基质中加过氧化钙可抵制pH值下降的趋势,并可补充氧气.     

Current progress of China＇s free ART program

China＇s Free ART Program was initiated in 2002 as an emergency response to save and improve the lives of AIDS patients living mainly in impoverished rural regions of central China. With little experience in HIV/AIDS treatment and care and resource limitations, China＇s efforts to provide widespread access to free antiretroviral therapy has been a process fraught with difficulty. However, the Free ART Program is progressing from an emergency response to a standardized treatment and care system. The development of national guidelines, training programs, a laboratory support network, a national patient database, programs for special populations such as children and patients living with coinfections, and operational research has improved the scope and quality of the free treatment program. As of June 30, 2005, a total of 19,456 patients in 28 provinces, autonomous regions, and special municipalities had received free ART. Challenges stemming from the nature of China＇s health system and patient population persist, but with strong government support and a diverse set of resources, China has the capacity to overcome these challenges and to provide nationwide access to high quality treatment and care.     

Biomechanism of impact resistance in the woodpecker’s head and its application

The woodpecker does not suffer head/eye impact injuries while drumming on a tree trunk with high acceleration(more than 1000×g) and high frequency.The mechanism that protects the woodpecker’s head has aroused the interest of ornithologists,biologists and scientists in the areas of mechanical engineering,material science and electronics engineering.This article reviews the literature on the biomechanisms and materials responsible for protecting the woodpecker from head impact injury and their applications in engineering and human protection.     

埃塞俄比亚塔纳湖鲤科鱼类体内亚美尼亚许氏绦虫Khawia armeniaca (Cholodkovsky, 1915) Shulman, 1958 (绦虫纲: 鲤蠢目) 的形态鉴定

在埃塞俄比亚境内塔纳湖中发现了1种寄生于鲤科鱼类: 间魮(Labeobarbus intermedius)和Labeobarbus tsanensis体内的许氏绦虫, 经形态学鉴定其为亚美尼亚许氏绦虫Khawia armeniaca (Cholodkovsky, 1915)(绦虫纲: 鲤蠢目)。该绦虫鉴别特征为头节呈半球状, 边缘光滑, 无皱褶; 睾丸分布区域从虫体中部至阴茎囊之前; 卵巢前卵黄腺分布于虫体中后部至阴茎囊前部区域, 少数排列在阴茎囊之后; 子宫起始于阴茎囊后方弯曲环绕直至卵巢后部区域, 有少许卵黄腺排列在子宫和卵巢的两侧。此外, K. armeniaca卵巢呈滤泡状或蝴蝶状, 雌雄生殖孔分离但彼此距离很近, 开口于体表并形成同一生殖腔, 且雄性生殖孔位于雌性生殖孔前方。卵巢后卵黄腺数目少于100个, 分布于虫体末端, 卵黄腺距离卵巢后翼较远, 部分样品内卵黄腺接近卵巢后翼。     

Maternal-effect Floped gene is essential for the derivation of embryonic stem cells in mice

Floped (official name Ooep) is specifically and abundantly expressed in mouse oocytes and embryonic stem cells (ESCs). Depletion of Floped from oocytes leads to early embryonic arrest at the 2-cell stage. Although crucial in cleavage stage development, its roles in early embryos as well as in ESCs remain completely unknown. Here, we compared the efficiency of mouse ESC derivation from inner cell mass (ICM) with and without Floped to study its possible roles in mESCs. Derivation rates of mESC from wild-type, heterozygous, and homozygous blastocysts were 33.3%, 21.43%, and 3.85%, respectively, indicating that Floped-/-blastocysts had significantly decreased derivation rates. Respective outgrowth appearing rate five days after blastocyst attachment were 83.3%, 85.7%, and 15.4%. Morphologically, the outgrowth of ICM from Floped-/-blastocysts appeared severely death three to five days after blastocyst attachment, and the respective derived stem cells showed long-term instability with long-standing epithelial-like colonies. This result suggests a possible role of Floped in the course of ICM-ESCs transition.     

Phylogenetic Analysis of Homologous Proteins Encoded by UL2 and UL23 genes of Herpesviridae

The proteins encoded by the Herpesviridae β-gene play a critical role in the replication stage of the virus.In this paper,phylogenetic analyses provided evidence that some β-gene products,such as UL2 and UL23 from HSV1,have their homologous genes in its family,and also exist in prokaryotic organisms,indicating that these viruses appear to have been assembled over evolutionary time by numerous independent events of horizontal gene transfer.     

Nestedness of waterbird assemblages in the subsidence wetlands recently created by underground coal mining

Nestedness has been a research focus in fields of island biogeography and community ecology in recent decades. Although nestedness of faunal assemblages has been investigated in natural wetlands, it remains largely unknown whether and why waterbird communities in artificial wetlands follow n ested patter ns. We exami ned the existence of n ested ness and un derlyi ng drivers in waterbird comm un ities in subside nee wetlands that are recently created by large-scale un derground coal mining in the North China Plain. Twelve point-count surveys for waterbirds were undertaken approximately every 2 weeks in 55 subside nee wetla nds from September 2016 to April 2017. We used the metric WNODF to estimate nestedness of the assemblages. Partial Spearman rank correlations were performed to examine the association between the nestedness and habitat variables (wetland area, landscape connectivity, wetland age, and habitat diversity) as well as life-history traits (body size, clutch size, dispersal ratio, geographical range size, and migrant status) related to species exti notion risk and colon izati on rate. Waterbird assemblages in the subside nee wetla nds were significantly nested. After controlling for other independent variables, the magnitude of nestedness was significantly and negatively correlated with wetland area and species trait linked to extinction risk (i.e., geographical range size). Our results indicate that selective extinction may be the main driver of the nestedness of waterbird assemblages in our study system. However, the nestedness was not due to passive sampling, selective colonization, or habitat diversity. From a conservation viewpoint, both large wetlands and waterbirds with a small geographic range should be protected to maximize the preserved species richness.     

Karyotyping of Brassica napus L. Based on C0t-1 DNA Banding by Fluorescence In Situ Hybridization

In order to precisely recognize and karyotype Brassica napus L. chromosomes, C0t-1 DNA was extracted from its genomic DNA, labeled with biotin-1 1-dUTP and in situ hybridized. The hybridized locations were detected by Cy3-conjugated streptavidin. Specific fluorescence in situ hybridization （FISH） signal bands were detected on all individual chromosome pairs. Each chromosome pair showed specific banding patterns. The B. napus karyotype has been constructed, for the first time, on the basis of both Cot-1 DNA FISH banding patterns and chromosome morphology.     

Heavy Metal Accumulation and Ecological Responses of Turfgrass to Rubbish Compost with EDTA Addition

Domestic rubbish compost is a complex-polluted system, containing multiple heavy metals,which limits its application. In the present study, Cr, Mn, Ni, Cu, Zn, Cd, and Pb accumulation and ecological responses of turfgrass to rubbish compost were investigated following the addition of EDTA. The results showed that the addition of EDTA significantly increased heavy metal accumulation in Lolium perenne L.and Festuca arundinacea L. Most heavy metal concentrations in L. perenne increased with increasing EDTA supply. The concentrations of Cr, Mn, Ni, Cu, and Cd in L. perenne were highest following the addition of 30 mmol/kg EDTA and the concentrations of Cr and Ni at this point reached concentrations of1914.17 and 521.25 μg/g, respectively. When the EDTA level was ＜ 20 mmol/kg, the accumulation of most heavy metals in F. arundinacea increased with increasing EDTA supply, but showed a tendency to decrease at EDTA concentrations ＞20 mmol/kg. The highest concentrations of Mn, Ni, Cu, and Zn in F.arundinacea reached 268.01, 110.94, 161.52 and 1 354.97 μg/g, respectively, following the addition of 20mmol/kg EDTA. The EDTA-induced increase in the accumulation of heavy metals in turfgrass was plantand metal-specific. L. perenne had a relatively high ability to accumulate Cr, Ni, and Zn. The highest Zn concentration was 2 979.58 μg/g and, following the addition of EDTA, the concentrations of the three metals were increased 26.23, 20.03, and 10.49-fold, respectively, compared with control. However, F. arundinacea showed a high ability to accumulate Cr, with the highest concentration (596.02 μg/g) seen following the addition of 30 mmol/kg EDTA; the concentration of Cr increased 15.51-fold compared with control. With EDTA addition, ecological responses of both turfgrass species showed that EDTA at concentrations ＜10mmol/kg increased seed germination and aboveground net primary production (ANP) of L. perenne and slightly inhibited those of F.arundinacea, but EDTA at concentrations ＞20 mmol/kg inhibited these parameters significantly for both species. Moreover, EDTA increased the chlorophyll and proline content at all concentrations tested. On the basis of the synthetic remediation index, the optimal EDTA concentration for turfgrass remediation of heavy metals in compost is approximately 10 mmol/kg.     

Respective and interactive effects of doubled CO2 and O3 concentration on membrane lipid peroxidation and antioxidative ability of soybean

Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined. But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2- generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.