Comparison of species ordinations resulting from alternative indices of interspecific association and different numbers of included species

Summary Several measures of interspecific association are compared. Dispersion and covariance are limited in value because they respond to the commonness of the species compared. Correlation is not so limited but it responds to discrepancies in commonness among the species. The practical result of these relationships between commonness and association is that only the most common species can occupy periferal positions in a species ordination. Rare species are relegated to positions near the center not on the basis of their phytosociological pattern but simply because of their rarity. Both Cole's index of association and the tetrachoric correlation overcome the problem imposed by the relationship between ordination position and species commonness and they both produce very similar results. The effect of differing numbers of species on the ordination configuration is examined using both Pearson's correlation and Cole's index. The basic pattern of the ordination is set with the first few species when Cole's index is used, however, since rare species are given more weight in the analysis with this index, the addition of several very rare species can change the configuration of the ordination.Nomenclature of species is given in Table 1.Research supported by the Eastern Deciduous Forest Biome Project, US-IBP, funded by the National Science Foundation under Interagency Agreement AG-199, BMS69-01147 A09 with the Energy Research and Development Administration — Oak Ridge National Laboratory. Research also supported by the U.S. Energy Research and Development Administration under contract with the Union Carbide Corporation. Contribution No. 240 from the EDFB, US-IBP. Publication No. 790. Environmental Sciences Division, ORNL.     

下一代益生菌Akk菌的研究进展

Akk菌(Akkermansia muciniphila)是具有巨大发展潜力的下一代益生菌,被广泛认为是改善炎症性肠病、肠易激综合征、糖尿病、肥胖症和渐冻症等疾病的一种新的潜在候选菌。近年来,随着人们对肠道共生菌重视程度的加深和各种组学技术的发展,Akk菌迅速成为益生菌研究领域的热点。然而,目前国内外有关Akk菌最新研究进展的归纳总结仍较少。因此,本文对近十年国内外有关Akk菌取得的最新研究进展进行综述,从Akk菌对宿主健康的调控作用,Akk菌的分离、鉴定和培养,以及Akk菌研究面临的挑战、机遇和前景等几方面进行阐述,以期为国内外同行对Akk菌的进一步深入研究和开发提供参考。     

Navigator-assisted hypofractionation (NAVAH) to address radiation therapy access disparities facing African-Americans with breast cancer

BackgroundAfrican-Americans have the highest overall cancer death rate and shortest survival time of any racial or ethnic group in the United States. The most common cancer studied in African-American radiation therapy (RT) access disparities research is breast cancer. The goal of this study is to evaluate the impact of patient navigation on RT access for African-American breast cancer patients.Material and methodsThis study is a prospective survey-based evaluation of the impact of patient navigation on access to hypofractionated RT and financial toxicity in African-American breast cancer patients. The impact of patient navigation on RT access will be collated and analyzed from survey results pre-RT versus post-RT as well as for patients with versus without receipt of patient navigation. The validated COST-Functional Assessment of Chronic Illness Therapy score will be used to compare hypofractionation versus standard fractionated RT financial toxicity for patients with early-stage breast cancer who have received lumpectomy.ConclusionThis is the first study to investigate the impact of patient navigation on reducing RT access disparities facing African-American breast cancer patients. The natural progression of this work will be to expand this model to include additional breast cancer populations most vulnerable to suffering RT access disparities (Native American, Hispanic American, Appalachian) within the United States.     

基于生态系统服务和生态系统健康的生态风险评价——以长株潭城市群为例

基于生态系统服务和生态系统健康的生态风险评估框架为城市群生态风险管理和国土生态修复提供新的视角。以生态风险评估框架为基础,综合运用生态系统服务、生态系统健康评估模型以及相关分析法对长株潭城市群展开生态风险评价,并对风险程度进行分类。结果表明:(1)城市群的城市化水平提升,区域生态风险也随之增加。生态系统服务价值、生态系统组织、生态系统活力、生态系统弹性等生态指数呈现下降趋势。(2)人工表面比率和生态指数之间的Pearson相关系数表明,人工表面比率与生态指数之间存在负相关关系,人工表面比率是生态风险提升的关键因素。(3)城市群人工表面比率要控制在36%以下,以进行生态风险管理和国土生态修复。总的来说,评价框架可以作为区域生态风险的评价终点。     

湖泊生态系统弹性系数理论及其应用

在湖泊生态系统健康评价的基础上,分析城市湖泊营养状态的特殊性,论证得出响应型和非响应型湖泊的生态系统健康指数(EHI)与营养状态指数(TSI)近似呈二次函数关系.提出湖泊生态系统弹性系数,对生态系统健康指数(EHI)做出适当改进.改进后的生态系统健康指数(EHI′)能够更好地反映各类型湖泊的健康状态,完善了Xu等的EHI理论并扩展了其应用范围,是目前最为接近Costanza对HI定义的可量化计算的数学公式和方法,并成功用于厦门杏林湾生态系统健康评价.     

Latitudinal comparison of altitudinal changes in forest structure,leaf-type,and species richness in humid monsoon Asia

A new template for mountain vegetation zonation along latitudinal gradients is proposed for examining geographical pattern of various forest attributes in humid monsoon Asia. The contrasting temperature regime in tropical and temperate mountains, i.e., the former is a non-seasonal, temperature-sum controlled environment, and the latter is a seasonal, low temperature limiting environment, leads to different altitudinal patterns of tree height distribution and species richness. In the tropical mountains, both tree height and species richness decrease steeply, and the tree height often stepwise. The decline of tree height and species diversity in the temperate mountains is far less pronounced except near the forest limit. Both trends are explained by their temperature regime.     

四川旋木雀一新亚种—天全亚种（雀形目：旋木雀科）

本文报道了旋木雀的一新亚种,命名为旋木雀天全亚种Ｃｅｒｔｈｉａ ｆａｍｉｌｉａｒｉｓ ｔｉａｎｑｕａｎｅｎｓｉｓ,并记述了新亚种同国内已知亚种区别的形态特征。     

Lifestyle factors and quality of life among primary health care physicians in Madinah,Saudi Arabia

BackgroundPhysicians are considered to be a high-risk population for a poor quality of life (QoL), but few studies of lifestyle factors include the QoL among them.ObjectivesThis study aimed to investigate the relationship between lifestyle factors and a positive QoL among primary health care (PHC) physicians.MethodsA cross-sectional study was conducted at 20 primary healthcare centers in Madinah, Saudi Arabia. A self-administered questionnaire was used, including sociodemographic characteristics, lifestyle data, and the short version of the World Health Organization Quality of Life questionnaire. Appropriate statistical analyses were used, including multivariate logistic regression models.ResultsThe response rate was 85.7% (72/84) physicians. The mean score of the total QoL and its four studied domains (physical, psychological, social, and environmental) was relatively high, with no statistically significant difference between the consultants and general practitioners. The positive total QoL in this study was significantly lower among physicians with obesity (OR = 0.55, 95%CI = 0.25–0.97), those using butter and animal fat for cooking (OR = 0.10, 95%CI = 0.02–0.81), and those eating meals out > 3 times per week (OR = 0.30, 95%CI = 0.10–0.90). Although non-significant, vegetable consumption and a high level of physical activity were associated with a positive QoL, with adjusted ORs of 2.5 (95%CI = 0.82–7.58) and 1.5 (95%CI = 0.33–6.65), respectively.ConclusionThe findings indicate a relatively good QoL among the participating physicians; however, a lower QoL was associated with unhealthy lifestyle factors. QoL was significantly associated with obesity, cooking practices, and eating meals from restaurants.     

Insight into the biological impact of COVID-19 and its vaccines on human health

COVID-19 (coronavirus disease-2019) is a contagious illness that has been declared a global epidemic by the World Health Organization (WHO). The coronavirus causes diseases ranging in severity from the common cold to severe respiratory diseases and death. Coronavirus primarily affects blood pressure by attaching to the angiotensin converting enzyme 2 (ACE 2) receptor. This virus has an impact on multiple organ systems, including the central nervous system, immune system, cardiovascular system, peripheral nervous system, gastrointestinal tract, endocrine system, urinary system, skin, and pregnancy. For the prevention of COVID-19, various vaccines such as viral-like particle vaccines, entire inactivated virus vaccines, viral vector vaccines, live attenuated virus vaccines, subunit vaccines, RNA vaccines, and DNA vaccines are now available. Some of the COVID-19 vaccines are reported to cause a variety of adverse effects that range from mild to severe in nature. SARS-CoV-2 replication is controlled by the RNA-Dependent RNA-Polymerase enzyme (RdRp). The availability of FDA-approved anti-RdRp drugs (Ribavirin, Remdesivir, Sofosbuvir, Galidesivir, and Tenofovir) as potent drugs against SARS-CoV-2 that tightly bind to its RdRp may aid in the treatment of patients and reduce the risk of the mysterious new form of COVID-19 viral infection. RdRp inhibitors, such as remdesivir (an anti-Ebola virus experimental drug) and favipiravir (an anti-influenza drug), inhibit RdRp and thus slow the progression of COVID-19 and associated clinical symptoms, as well as significantly shorten recovery time. Molnupiravir, an orally active RdRp inhibitor and noval broad spectrum antiviral agent, is an isopropyl pro-drug of EIDD-1931 for emergency use. Galidesivir's in vitro and in vivo activities are limited to RNA of human public health concern. Top seeds for antiviral treatments with high potential to combat the SARS-CoV-2 strain include guanosine derivatives (IDX-184), setrobuvir, and YAK. The goal of this review is to compile scattered information on available COVID-19 vaccines and other treatments for protecting the human body from their harmful effects and to provide options for making better choices in a timely manner.