四川若尔盖县不同退化程度高寒草地群落比较研究

于2008年、2009年在若尔盖县沿高寒草地退化梯度进行物种多样性和生物量等方面的群落监测,以期探讨不同退化程度高寒草地群落结构特征,并提出引起退化的原因.结果表明:(1)随着退化加剧,草地群落盖度、群落物种丰富度、Shannon-Wiener指数和Pielou指数均递减.未退化群落以鹅绒委陵菜、无脉苔草为优势种,群落...     

四川卧龙亚高山林线生态交错带群落的种多度关系

以盖度作为物种多度指标,用描述物种多度分布的模型：断棍分布、几体级数分布、对数级数分布和截尾对数正态分布研究了卧龙巴郎山岷江冷棚林线交错带附近草本群落的种－－我镀分布关系。结果表明,截尾对数正态分布和对数级数分布能较好地拟合交错带附近群落的种－多度分布,截尾对数正态分布模型更适合交错带群落,对数级数分布 较好地适合亚高山草甸群落。对数级数分布的参数α和对数正态分布的参数λ是反映群落结构特征内在性质     

Prevalence rate and risk factors of human cystic echinococcosis: A cross-sectional,community-based,abdominal ultrasound study in rural and urban north-central Chile

BackgroundCystic echinococcosis (CE) caused by Echinococcus granulosus sensu lato (s.l.) is a neglected and underdiagnosed parasitic zoonosis that has a significant socioeconomic impact on rural communities relying on livestock farming. CE is endemic across Latin America, including Chile, where the Coquimbo region exhibits a relatively high record of hospital-based human cases and infected animals. However, the incidence of hospitalized CE cases may underestimate the real burden of infection in a population, since the majority of cases never reach medical attention or official disease records.Methodology/Principal findingsIn 2019, a cross-sectional, community-based study was conducted with the objectives of estimating for the first time the prevalence of human abdominal CE using abdominal ultrasound (US) screening in volunteers residing in urban and rural localities of the Monte Patria municipality located in Limarí province, Coquimbo region, Chile, and identifying the risk factors associated with human infection. Pre-screening activities included a 16-h lecture/hands-on training aimed at rural physicians that focused on the diagnosis of CE by US, based on current WHO recommendations. A total of 2,439 (~8% of municipality inhabitants) people from thirteen target localities were screened by abdominal US in June-July 2019. We found an overall CE prevalence of 1.6% (95% CI 1.1–2.2) with a significantly higher likelihood of infection in rural localities, older age classes and people drinking non-potable water; 84.6% of infected volunteers were newly diagnosed with CE. Cysts were either in active or inactive stages in equal proportions; active cysts were detected in all age classes, while 95.7% of inactive cysts occurred in >40 years-old subjects.Conclusions/SignificanceThis is the first US survey aimed at detecting human infection caused by Echinococcus granulosus s.l. in Chile. Our findings indicate a high CE prevalence in the area, and contribute to define the demographic and behavioral risk factors promoting the transmission of the parasitic infection within target communities. Our results support the implementation of cost-effective strategies for the diagnosis, treatment and control of CE, and the need to improve the epidemiological surveillance system in Chile.     

降水量对川西北高寒草甸牦牛粪分解速率的影响

青藏高原高寒草甸的降水年际变化很大,而且在未来全球气候变化的背景下可能进一步增大.为了研究降水量变化对川西北高寒草甸牦牛粪分解的潜在影响,通过塑料膜覆盖(去除降水)、模拟额外增水(增水量为实际降水量的50％)和对照(野外无干扰情形)形成3种不同的水分处理.测定了牛粪的含水量、干重及氮磷含量,并统计了主要分解者(手捡法获取粪食性甲虫及其幼虫)的种类和数量.结果发现:覆盖处理显著地降低了牛粪含水量、牛粪中的粪食性甲虫数量与牛粪分解量,但增水处理并没有显著影响牛粪的分解进程,可能与实验期间降水量较高有关.在牛粪分解前期,粪食性甲虫数量与牛粪含水量之间正相关,而牛粪分解量与粪食性甲虫数量之间正相关,说明牛粪含水量的高低影响了粪食性甲虫数量,进而决定了牛粪分解量.但是,降水量的人为增加或减少均没有显著地改变牛粪中的全氮和全磷含量.总体上看,在高寒草甸的放牧生态系统中,降水量的减少将会降低牛粪的分解速率、延长牛粪分解过程,从而可能会降低生态系统的生产力水平.     

川西亚高山不同暗针叶林群落类型的冠层降水截留特征

在林分和小流域尺度上,应用模型研究了四川卧龙亚高山暗针叶林冠层的降水截留特征.结果表明:生长季节(5—10月),箭竹-岷江冷杉原始林冠层截留系数在33%～72%之间,平均48%;冠层截留量与降水量之间呈显著的线性关系,截留系数与降水量之间呈负指数函数关系;试验小流域内,植被冠层最大截留量的平均值为1.74mm,不同林分间的差异显著,其顺序为藓类-箭竹-岷江冷杉林>草类-箭竹-岷江冷杉林>藓类-杜鹃-岷江冷杉林>草类-杜鹃-岷江冷杉林>杜鹃灌丛;冠层最大截留量与叶面积指数(LAI)之间呈极显著的线性关系;冠层截留量、冠层最大截留量、附加截留量分别占同期降水量的39%、25%和14%.所选模型对整个生长季平均截留量的模拟效果较好,相对误差为9%～14%.     

Natural history of cystic echinococcosis in humans

This study provides a contribution to understanding of the natural history of the hydatid cyst during its evolution in the human liver examining the high morphostructural variability of larval forms of Echinococcus granulosus. A detailed study of a large sample of intact cysts removed from patients surgically treated by means of total pericystectomy, has enabled to outline the different developmental stages of the parasite over time, up to its death and complete degeneration.     

Economic impact of cystic echinococcosis in peru

Background

Cystic echinococcosis (CE) constitutes an important public health problem in Peru. However, no studies have attempted to estimate the monetary and non-monetary impact of CE in Peruvian society.

Methods

We used official and published sources of epidemiological and economic information to estimate direct and indirect costs associated with livestock production losses and human disease in addition to surgical CE-associated disability adjusted life years (DALYs) lost.

Findings

The total estimated cost of human CE in Peru was U.S.$2,420,348 (95% CI:1,118,384–4,812,722) per year. Total estimated livestock-associated costs due to CE ranged from U.S.$196,681 (95% CI:141,641–251,629) if only direct losses (i.e., cattle and sheep liver destruction) were taken into consideration to U.S.$3,846,754 (95% CI:2,676,181–4,911,383) if additional production losses (liver condemnation, decreased carcass weight, wool losses, decreased milk production) were accounted for. An estimated 1,139 (95% CI: 861–1,489) DALYs were also lost due to surgical cases of CE.

Conclusions

This preliminary and conservative assessment of the socio-economic impact of CE on Peru, which is based largely on official sources of information, very likely underestimates the true extent of the problem. Nevertheless, these estimates illustrate the negative economic impact of CE in Peru.     

四川龙门山西北部植被分布与地形因子的相关性

在利用GIS技术提取地形统计数据的基础上,采用关联分析和因子分析法对四川龙门山西北部的植被分布与地形因子的相互关系进行了分析。结果表明,在该区域内,植被分布与地形因子均有显著关联。其中地形因子中的海拔对植被分布的影响最大,其第一主分量的因子载荷达到0.929,充分体现了其通过影响温度条件而限制植被分布的特点。此外,植被分布还受坡度及坡向的影响,二者在第二主分量和第三主分量中的因子载荷分别为0.989和0.998,这体现了它们通过影响水分和光照条件从而间接影响植被生长发育的特点,但由于其变化幅度不大,对植被分布的影响小于海拔因子。     

Past and present of cystic echinococcosis in Bolivia

Viable eggs of the canine intestinal tapeworm Echinococcus granulosus sensu lato (s.l.) infect various intermediate hosts causing cystic echinococcosis (CE). Furthermore, CE represents a serious zoonosis causing a significant global burden of disease. CE is highly endemic in South America, including Argentina, Brazil, Chile, Uruguay, and Peru. For Bolivia, no official data concerning the incidence in humans or the number of livestock and dogs infected are available. However, it is well known that CE occurs in Bolivia. We aim here to fill the gap in the current knowledge of the epidemiological situation of CE in Bolivia, providing a historical overview of documents published within the country, which have never been comprehensively reviewed. The very first documentation of E. granulosus infection in animals dates in 1910, while the first human case was reported in 1913. In total, 876 human CE cases have been reported in the scientific literature, with an apparent increase since the 1970s. In the absence of other epidemiological studies, the highest prevalence in human comes from Tupiza, Potosí Department, where 4.1% (51/1,268) of the population showed signs of CE at mass ultrasound screening in 2011. In the same report, 24% of dog faecal samples were positive for coproantigens of E. granulosus s.l. in ELISA. The highest prevalence in intermediate hosts reported at abattoir reached 37.5% in cattle from Potosí, followed by 26.9% in llamas from Oruro, 2.4% in pigs and 1.4% in sheep from La Paz. Finally, Echinococcus granulosus sensu stricto (s.s.), Echinococcus ortleppi (G5), and Echinococcus intermedius (G7) have been identified in Bolivia. Data reviewed here confirm that E. granulosus s.l. is circulating in Bolivia and that a proper prospective nationwide epidemiological study of CE is urgently needed to define transmission patterns as a basis for the planning and implementation of future control measurements.     

Early diagnosis, treatment and follow-up of cystic echinococcosis in remote rural areas in Patagonia: impact of ultrasound training of non-specialists

Cystic echinococcosis (CE) is a chronic, complex and neglected disease caused by the larval stage of Echinococcus granulosus. The effects of this neglect have a stronger impact in remote rural areas whose inhabitants have no chances of being diagnosed and treated properly without leaving their jobs and travelling long distances, sometimes taking days to reach the closest referral center.

Background

In 1980 our group set up a control program in endemic regions with CE in rural sections of Rio Negro, Argentina. Since 1997, we have used abdominopelvic ultrasound (US) as a screening method of CE in school children and determined an algorithm of treatment.

Objectives

To describe the training system of general practitioners in early diagnosis and treatment of CE and to evaluate the impact of the implementation of the field program.

Materials and Methods

In 2000, to overcome the shortage of radiologists in the area, we set up a short training course on Focused Assessment with Sonography for Echinococcosis (FASE) for general practitioners with no previous experience with US. After the course, the trainees were able to carry out autonomous ultrasound surveys under the supervision of the course faculty. From 2000 to 2008, trainees carried out 22,793 ultrasound scans in children from 6 to 14 years of age, and diagnosed 87 (0.4%) new cases of CE. Forty-nine (56.4%) were treated with albendazole, 29 (33.3%) were monitored expectantly and 9 (10.3%) were treated with surgery.

Discussion

The introduction of a FASE course for general practitioners allowed for the screening of CE in a large population of individuals in remote endemic areas with persistent levels of transmission, thus overcoming the barrier of the great distance from tertiary care facilities. The ability of local practitioners to screen for CE using US saved the local residents costly travel time and missed work and proved to be an efficacious and least expensive intervention tool for both the community and health care system.     

四川省藓类植物新记录

在对四川省第一高峰贡嘎山的野外调查和1 000余份采集标本鉴定的基础上,现已知贡嘎山有藓类植物40科,133属,321种.其中,隶属于10科,12属的12种为四川省苔藓植物新记录种.该文就新记录种进行详细报道,为中国和四川省的苔藓植物区系研究提供新的资料.     

四川绵阳地区水鸟的多样性分析

2000年1月～2003年1月,采用样线法对绵阳地区水鸟进行调查,共记录7目10科30属58种。其中有各级保护动物19种,留鸟12种(20．7％),夏候鸟4种(6．92％),旅鸟、冬候鸟各21种(36．19％)。区系组成包括：古北型43种(74．1％),东洋型9种(15．5％),广布型6种(10．4％)。多样性分析得出绵阳地区水鸟Shannon-Winer指数H’=2．5736、Pielou指数J=0．6338及G-F指数DG-F=0．5936。在3种不同类型湿地生以涪江境中,河谷多样性最丰富。同时指出,自然环境恶化和人类活动是该地区水鸟面临的主要威胁。     

Assessment of a 10-year dog deworming programme on the transmission of Echinococcus multilocularis in Tibetan communities in Sichuan Province,China

Human alveolar echinococcosis (AE) is considered a neglected zoonotic disease by the World Health Organization (WHO). The causative pathogen, Echinococcus multilocularis, lives as an adult tapeworm in the intestinal tract of canines. AE was identified as an emerging public health issue in Tibetan communities of Shiqu County 20 years ago. On St. Lawrence Island, Alaska (USA), in the 1980s peri-domestic transmission of E. multilocularis was controlled by regular deworming of owned dogs over a 10-year period. In Tibetan communities, on the Tibetan Plateau, control of E. multilocularis transmission is challenging due to the continental setting, complex epidemiology, disease ecology, geography, and socio-cultural factors. However, a control programme based on deworming owned dogs using praziquental (PZQ) has been carried out since 2006. Assessment was conducted in townships where baseline data were available 10 years prior. Purging of dogs by oral administration of arecoline was used to measure E. multilocularis prevalence, trapping small mammals around communities was employed to assess the change in infection of pikas and voles, and analysis of human AE abdominal ultrasound-based data was used to understand the change in prevalence in the past decade. In all three evaluated townships, the E. multilocularis prevalence in owned dogs was significantly (P < 0.01) reduced from 7.23% (25/346) during 2000–2003 to 0.55% (1/181) in 2016. Human AE ultrasound-based prevalence (adjusted for age and sex) in five evaluated townships decreased significantly (P < 0.01) from 6.25% (200/3,198) during 2000–2002 to 3.67% (706/19,247) during 2015–2017. The 2016 prevalence of E. multilocularis metacestodes in small mammal intermediate hosts was not significantly different from the prevalence in 2008. The control programme was effective in reducing E. multilocularis infection in owned dogs and human AE prevalence, but did not significantly impact infection in wildlife intermediate hosts.     

鹮嘴鹬夜栖地报道

2010年在四川省稻城地区发现鹮嘴鹬3个夜栖地,采用样方法调查其夜栖地的生境特征,并设置对照样方15个。研究结果表明河滩宽度、河心岛面积和石头盖度为关键因子。     

生态斑块重要性综合评价方法研究——以四川省为例

生态斑块为生物提供生存和发展的场所,城市化的推进引发生态斑块面积锐减且趋于破碎化,严重威胁生态系统服务。通过对生态斑块重要性的分析,可识别对保持景观连接度有关键作用的区域,是优化有限资金配置、实现高效生态保护和分级管理的有效途径。以2015年的四川省为例,从景观连接度出发,基于网络建模和拓扑指标计算,结合逼近理想点排序法(TOPSIS)和有序样品聚类进行了斑块重要性的综合评估和排序。研究结果表明,四川省内生态斑块呈现西北部相对连续,南部和东部零散而稀疏的分布特点,在此基础上构建的生态基础设施网络具有无标度性;所选拓扑指标结合综合评价方法后可有效评估斑块重要性,所有斑块可分为5个重要性层级,高层级斑块主要位于相对核心的位置,低层级斑块分布于全省边缘。针对不同层级斑块的特点提出了相应规划建议,从整体角度出发引导局部生态规划,以期为有限资源下省域尺度复合种群保护工作提供参考与借鉴。     

Mental health problems among children one-year after Sichuan earthquake in China: a follow-up study

Background

On May 12, 2008, a destructive earthquake registering 8.0 on the Richter scale struck Sichuan Province, southwest China. Beichuan County was the epicenter which was one of the areas nearly completely destroyed by the earthquake. In Beichuan, about 15000 people died and 3000 people were missing. Specially, the earthquake took 1587 students'' and 214 teachers'' lives from the elementary and middle schools there. The main purpose of the study was to provide a better understanding of mental health problems and associated risk factors among children after earthquake.

Method

Three hundred and thirty grades 3–5 children completed the questionnaire of disaster –related experience and the Trauma Symptom Checklist for Children-Alternate Version (TSCC-A). The first survey was carried out six months after the earthquake, and the second one was carried out six months later. The measurements and methodology applied in the two sessions were identical.

Results

The prevalence rates of the problems at two time-points were 23.3% and 22.7% for anxiety, 14.5% and 16.1% for depression, and 11.2% and 13.4% for PTSD, respectively. Among demographic variables, no significant age difference existed, while it was found that 6 months after the earthquake, symptoms of anxiety, depression and PTSD were significantly more common among students in grades 4 and 5 than those in grade 3, Initial exposure to death, bereavement and extreme fear were significant predictive factors for the occurrence of anxiety, depression and PTSD.

Conclusions

Findings of this study suggest that posttraumatic mental health problems after natural disaster in children may have reached epidemic proportions and remain high for a long period. Psychologist and social workers should pay more attention to children who experienced more traumatic stresses and provide appropriate mental health interventions. Implications and limitations of these findings were discussed.     

四川串珠藻属一新种

发表了四川串珠藻属一新种,即彭州串珠藻(Batrachospermum pengzhouense S.L.Xieet Z.X.Shi)。     

A new species of Arctomia from Sichuan Province,China

Arctomia teretiuscula sp. nov. (Arctomiaceae) is described from Sichuan Province, China. A minutely coralloid, bryophilous cyanolichen, it is a further example of the biogeographical link between the lichen biotas of the Himalayan region and the Arctic. A key to the three accepted species of Arctomia is provided.