Determinants of reef fish assemblages in tropical Oceanic islands

Diversity patterns are determined by biogeographic, energetic, and anthropogenic factors, yet few studies have combined them into a large‐scale framework in order to decouple and compare their relative effects on fish faunas. Using an empirical dataset derived from 1527 underwater visual censuses (UVC) at 18 oceanic islands (five different marine provinces), we determined the relative influence of such factors on reef fish species richness, functional dispersion, density and biomass estimated from each UVC unit. Species richness presented low variation but was high at large island sites. High functional dispersion, density, and biomass were found at islands with large local species pool and distance from nearest reef. Primary productivity positively affected fish richness, density and biomass confirming that more productive areas support larger populations, and higher biomass and richness on oceanic islands. Islands densely populated by humans had lower fish species richness and biomass reflecting anthropogenic effects. Species richness, functional dispersion, and biomass were positively related to distance from the mainland. Overall, species richness and fish density were mainly influenced by biogeographical and energetic factors, whereas functional dispersion and biomass were strongly influenced by anthropogenic factors. Our results extend previous hypotheses for different assemblage metrics estimated from empirical data and confirm the negative impact of humans on fish assemblages, highlighting the need for conservation of oceanic islands.     

影响微生物接种剂发挥作用的因素

大量施用化肥不仅造成了环境污染,而且也是一个能源消耗的问题.在生态农业中,通过向土壤中接种有益微生物部分替代化肥已是科学家研究的热点.微生物通过活化土壤养分、抑制病原菌、降解有毒污染物等方式发挥作用,然而,微生物要发挥功效必须在土壤中能够定殖.本文主要针对国内外在影响微生物根际定殖的因素以及影响引入微生物活性的因素两方面的研究进行综述,同时强调对接种剂引入所引起的生物种群及生态环境变化应予以重视.     

影响微生物接种剂发挥作用的因素

大量施用化肥不仅造成了环境污染, 而且也是一个能源消耗的问题。在生态农业中, 通过向土壤中接种有益微生物部分替代化肥已是科学家研究的热点。微生物通过活化土壤养分、抑制病原菌、降解有毒污染物等方式发挥作用, 然而, 微生物要发挥功效必须在土壤中能够定殖。本文主要针对国内外在影响微生物根际定殖的因素以及影响引入微生物活性的因素两方面的研究进行综述, 同时强调对接种剂引入所引起的生物种群及生态环境变化应予以重视。     

Differential expression of sympathoadrenal lineage-determining genes and phenotypic markers in cultured primary neural crest cells

Bone morphogenetic protein-2 (BMP-2) promotes the development of primary neural crest cells grown in tissue culture to the sympathoadrenal (SA) lineage. Independent studies have characterized the expression patterns of SA-lineage genes in developing chicken embryo; however, studies using cultured primary neural crest cells have characterized only the expression patterns of the catecholaminergic markers, tyrosine hydroxylase (TH) and catecholamines (CAs). To further explore the molecular mechanisms that control SA-cell development using the in vitro model system, it is crucial to define the expression patterns of both the catecholaminergic markers and the genes regulating SA-lineage determination. Accordingly, we defined, in the absence and presence of BMP-2, the temporal expression patterns of TH and CA, the SA lineage-determining genes ASH-1, Phox2a, and Phox2b, the GATA-2 gene, and the pan-neuronal SCG10 gene. Comparison of these data with the reported temporal and spatial patterns of expression in vivo demonstrate that the inductive steps of SA-lineage determination, including the specification of neurotransmitter identity and neuronal fate, are recapitulated in the neural-crest culture system.     

The influence of biological and environmental factors on metallothionein concentration in the blood

The concentration of metallothionein (MT), a low-molecular-weight protein, is regulated by many factors, primarily metals (zinc, cadmium, copper), cytokines, glucocorticoides and free radicals. These factors are determined by such aspects of human biology as gender, pregnancy and age, as well as by environmental factors including the use of oral contraceptives and cigarette smoking, all which may affect MT levels in the body.The aim of this study was to investigate the influence of these biological and environmental factors on MT concentrations in erythrocyte lysate and in plasma.MT concentrations were determined by a two-step direct enzyme-linked immunosorbent assay. Evaluation of exposure to cigarette smoking was performed by checking cotinine levels in the plasma of subjects.The studies showed higher MT concentrations in both the erythrocyte lysate and plasma of women when compared to men. Furthermore, pregnancy causes an increase of MT concentration in plasma, while oral contraceptives cause an elevated concentration of MT in erythrocyte lysate. Age impacts plasma MT concentrations in men, whereas it does not affect concentrations of MT in erythrocyte lysate.     

植物环境响应启动子的诱导元件及转录因子

光、温度、水分等环境因素影响植物的生长发育,植物可以通过启动子中顺式作用元件与转录因子的相互协调作用,对这些信号产生响应,调控基因表达。本文综述了光、温度、水分诱导表达启动子中的顺式作用元件及相关转录因子研究的最新进展,从分子水平上探讨了环境因子诱导的基因表达调控,对研究植物适应环境的机制具有一定的意义。     

网柄细胞状黏菌生态学的研究进展

网柄细胞状黏菌(简称网柄菌)是黏菌的第二大类群,对其生态特征的研究有助于深入了解这类生物适宜的生存条件和人类活动的影响。本文回顾了1869年至今的网柄菌生态学研究历史,从地理因素、植被因素、生物因素三个角度,探讨了影响网柄菌物种丰度和多度的生态因素,从而为土壤及凋落物中黏菌的物种多样性保护提供参考。     

武夷山风景区马尾松毛虫发生趋势与环境因子的相关性

应用DPS数据处理系统分析武夷山风景区环境因子与马尾松毛虫发生趋势的关系,利用2007年武夷山风景区气象和地理因子进行主成分因子分析。结果表明,降雨量与马尾松毛虫的发生量关系显著,但受地区性影响大;海拔和纬度与马尾松毛虫的发生量关系显著,但受人为活动的影响大。     

Analysis on new occurrence records of red imported fire ant (Solenopsis invicta Buren) in China in 2021

Solenopsis invicta Buren, also known as the red imported fire ant (RIFA), has had a very negative effect on biological diversity, public safety, agriculture, and economics. Because of the growth in global trade, the RIFA threat to China will continue to increase. To better understand characteristics of newly observed distributions of RIFA, we studied the effects of three factors including provincial areas, landcover types, and climatic conditions on the 130 new occurrence records in 2021. (1) We found that RIFA preferred to invade Sichuan and Guangxi, and provinces that are large agricultural producers were more vulnerable to invasive RIFA. Guangdong was the most damaged province, and wealthy provinces, especially southeastern coastal provinces, were more at risk and suffered a bigger loss from the further RIFA threat. (2) Compared with other habitats, plantations received more significant damage from invasive RIFA. (3) Areas with an annual precipitation of 516.4 mm, annual average temperature of 18.6°C, or elevation of 569.9 m had a great abundance of invasive RIFA. Our study suggests that stringent inspection and quarantine measures are necessary in new occurrence areas to prevent further RIFA outbreak, and highlights the need for cross-provincial cooperation and national coordination to slow its spread.     

Arterial cells and CNS sheath cells from Aplysia californica produce factors that enhance neurite outgrowth in co-cultured neurons

Substrate-bound and soluble factors regulate neurite outgrowth and synapse formation during development, regeneration, and learning and memory. We report that sheath cells from CNS connectives and arterial cells from the anterior aorta of the sea slug, Aplysia californica, enhance neurite outgrowth from co-cultured Aplysia neurons. Sheath and arterial cell cultures contain several cell types, including fibrocytes, myocytes, and amoebocytes. When compared to controls (neurons with defined growth medium alone), the percentage of neurons with growth and the average neurite lengths are significantly enhanced by sheath and arterial cells at 48 h after plating of the neurons; these parameters are comparable to those of neurons cultured in medium containing hemolymph. Our results indicate that sheath cells produce substrate-bound factor(s) and arterial cells produce diffusible factor(s) that promote growth. These growth factors likely promote neuron survival and neurite outgrowth during neural plasticity exhibited in the adult CNS. Electronic Publication     

Analysis of differential proteomes in pathogenic and non‐pathogenic Leptospira: Potential pathogenic and virulence factors

Leptospirosis is a bacterial zoonotic disease caused by spirochetes in the genus Leptospira. To date, factors determining the pathogenicity and virulence of leptospires remain unclear. We performed a gel‐based proteomic analysis to evaluate differential leptospiral proteomes in the pathogenic L. interrogans (serovars Australis, Bratislava, Autumnalis, and Icterohaemorrhagiae) and the non‐pathogenic L. biflexa (serovar Patoc). Quantitative proteome analysis and MS protein identification revealed 42 forms of 33 unique proteins whose levels were significantly greater in the pathogenic serovars compared with the non‐pathogenic serovar. Among the four pathogenic serovars, the more virulent serovar Icterohaemorrhagiae (which is most commonly associated with severe leptospirosis in patients) had significantly greater levels of 14 forms of 12 unique proteins, when compared with the other three pathogenic serovars. Some of these identified proteins may serve as the pathogenic and/or virulence factors of leptospirosis.     

The future excess fraction of cancer due to lifestyle factors in Australia

BackgroundMany cancers are caused by exposure to lifestyle, environmental, and occupational factors. Earlier studies have estimated the number of cancers occurring in a single year which are attributable to past exposures to these factors. However, there is now increasing appreciation that estimates of the future burden of cancer may be more useful for policy and prevention. We aimed to calculate the future number of cancers expected to arise as a result of exposure to 23 modifiable risk factors.MethodsWe used the future excess fraction (FEF) method to estimate the lifetime burden of cancer (2016–2098) among Australian adults who were exposed to modifiable lifestyle, environmental, and occupational risk factors in 2016. Calculations were conducted for 26 cancer sites and 78 cancer-risk factor pairings.ResultsThe cohort of 18.8 million adult Australians in 2016 will develop an estimated 7.6 million cancers during their lifetime, of which 1.8 million (24%) will be attributable to exposure to modifiable risk factors. Cancer sites with the highest number of future attributable cancers were colon and rectum (n = 717,700), lung (n = 380,400), and liver (n = 103,200). The highest number of future cancers will be attributable to exposure to tobacco smoke (n = 583,500), followed by overweight/obesity (n = 333,100) and alcohol consumption (n = 249,700).ConclusionA significant proportion of future cancers will result from recent levels of exposure to modifiable risk factors. Our results provide direct, pertinent information to help determine where preventive measures could best be targeted.     

昆明西山滇青冈林内滇青冈种子库动态的研究

通过对昆明西山滇青冈林内滇青冈种子库的跟踪取样调查和种子埋藏试验,对滇青冈种子库的动态进行了研究。昆虫在种子成熟前侵入种子,经种子雨进入种子库时已有71.8%的种子失去萌发能力。种子雨输入种子库的绝大部分种子停留在表面种子库,其中48.55%的种子被虫害,25.36%被某些非生物或生物搬运,17.39%的腐烂,8.7%的被动物当场取食,没有种子萌发,影响种子库动态的各种因子的作用大小在时间上是变化。被搬运的种子中,有4.9%的由表面种子库转移到埋藏种子库。土层是滇青冈种子的安全生境,土壤种子库的存在时间超过250天。埋入土壤的试验种子一直处于静止状态,到6月雨季后有80%种子萌发,20%的腐烂。萌发种子数是当年产种子的0.26%。滇青冈林内的滇青冈种子库是季节性的,种子库对种群个体的补充作用是有限的。     

胰胆管造影术后发生胰腺炎的危险因素分析

目的:探讨经胰胆管造影术后患者发生胰腺炎的危险因素,以期为临床实践提供一定的参考依据。方法:回顾性分析2015年1月1日至2018年1月1日入住我院行胰胆管造影术的患者,根据纳入排除标准,分成胰腺炎组和非胰腺炎组,比较分析两组患者的性别、年龄、既往行内镜逆行性胰胆管造影术(endoscopic retrograde pancreatic cholangiography,ERCP)与否、ERCP次数、ERCP手术时间、胆道括约肌气囊扩张术、插管困难等因素和血清炎症因子TNF-α、IL-1、IL-6、IL-10的表达情况。结果:研究共纳入1891例患者,并发胰腺炎者124例(6.55%),非胰腺炎患者1767例。性别、年龄、既往行ERCP、ERCP次数、ERCP手术时间、胆道括约肌气囊扩张术、插管困难均为胰腺炎发生的危险因素,且ERCP手术时间和胆道括约肌气囊扩张术是为并发胰腺炎的独立危险因素。ERCP术后胰腺炎组血清TNF-α、IL-1、IL-6、IL-10的表达水平均显著高于非胰腺炎组(P0.05)。结论:ERCP手术时间、胆道括约肌气囊扩张术及高血清炎症因子水平可能是并发胰腺炎的独立危险因素。     

职业倦怠与性别的相关性及其生物学基础的研究*

从上个世纪七十年代开始,职业倦怠就引起了欧美发达国家相关学者的关注。在中国,对这方面的研究相对较少。近年来,随着我国社会经济的快速发展,人们的工作压力增大,而职业倦怠对人们工作和生活造成的影响也日趋严重,已经成为日常生活中一个不可回避的问题。男性和女性之间职业倦怠的表现和程度存在一定差异,本文从环境和生物学的角度分析男性和女性之间职业倦怠的表现和程度不同的原因。     

Polyphenols of Leaf,Litter and Soil of Pinus bungeana across China and Their Responses to Ecological Factors

The importance of phenolic compounds for responding to various environmental conditions has been widely emphasized. However, the role of interactions between polyphenols and ecological factors, especially C, N, and P stoichiometry was little studied. Here, 15 sites across five provinces of Pinus bungeana in temperate regions of China were studied. The results showed that the higher values of total phenolic contents (TPC) of leaf and litter were distributed among the north distribution area of P. bungeana, lower values were in the south, whereas soil TPC were contrary to leaf and litter TPC. The stepwise regression, path analysis and decision index of path analysis for leaf TPC and ecological factors showed that altitude had the most direct impact on leaf TPC. Moreover, the principal determinants of leaf, litter and soil TPC were soil C/P ratios, longitude, and soil N/P ratios, respectively. In addition, the leaf, litter and soil TPC of P. bungeana were limited by soil C/N ratios, mean annual temperature, and soil P, respectively. Overall, our study provided evidence that ecological factors affected strongly the leaf, litter and soil TPC of P. bungeana.     

Microbial levan from Brachybacterium phenoliresistens: Characterization and enhancement of production

Levan producing bacteria was isolated from rhizosphere soil. The molecular identification of this isolate was conducted using 16S rRNA, which resulted in a sequenced region of 1298 base pairs. The sequence alignment in the gene bank indicated that this isolate has a high percentage of similarity (99%) to the retrieved consensus sequence of Brachybacterium phenoliresistens strain phenol-A. The produced levan was characterized using TLC, FTIR, 1H NMR and 13C NMR spectroscopy techniques. The effects of nutritional and physical factors on this isolate’s levan production were investigated. The results demonstrated that the optimal sources for carbon and casein during levan production were sucrose and casein, yielding 7.88 g/land 8.12 g/l of levan, respectively. The highest levan yield (7.97 g/l) was obtained at a sucrose concentration of 300 g/l. At an initial pH of 7.8, this bacterium yielded their highest levan production of 7.88 g/l. The optimal incubation period was 72 h with a yield of 8.58 g/l, the optimal temperature was 30 °C and resulted in 7.87 g/l, and the highest levan production yield was obtained at 150 rpm and yielded 8.12 g/l.     

Decomposition in salt marsh ecosystems of the S.W. Netherlands: the effects of biotic and abiotic factors

Decomposition rates, determined with the litterbag technique in salt marshes of the S.W. Netherlands during the past decade are compared; the biotic and abiotic factors influencing these rates are identified and discussed.Tissue composition is the main variable affecting decay rates of halophytes, particularly variations in lignin content between plant parts and between species.Experiments in which the loss of the tensile strength of cotton strips was used as an index of cellulolytic decay, show that there is a conspicuous variation in decay rates on different sites in a salt marsh. Nonetheless, the locally varying environmental conditions within salt marshes of the S.W. Netherlands have less impact on the variation in decomposition rates of halophyte litter than the chemical make-up of the plant material.Larger fauna elements (> 300 m) may increase decomposition rates, but this effect is only limited and depends on location and litter type. The role of small fauna elements such as nematodes, which occur abundantly in association with halophyte litter, remains largely unknown.     

茶树根系生长及其影响因子研究进展

本文主要综述茶树根系的结构、特点、功能与生长营养特性,以及近些年来影响和调控茶树根系生长的非生物和生物因子的研究进展,并对进一步研究进行展望。