Composite Sampling Approaches for Bacillus anthracis Surrogate Extracted from Soil

Any release of anthrax spores in the U.S. would require action to decontaminate the site and restore its use and operations as rapidly as possible. The remediation activity would require environmental sampling, both initially to determine the extent of contamination (hazard mapping) and post-decon to determine that the site is free of contamination (clearance sampling). Whether the spore contamination is within a building or outdoors, collecting and analyzing what could be thousands of samples can become the factor that limits the pace of restoring operations. To address this sampling and analysis bottleneck and decrease the time needed to recover from an anthrax contamination event, this study investigates the use of composite sampling. Pooling or compositing of samples is an established technique to reduce the number of analyses required, and its use for anthrax spore sampling has recently been investigated. However, use of composite sampling in an anthrax spore remediation event will require well-documented and accepted methods. In particular, previous composite sampling studies have focused on sampling from hard surfaces; data on soil sampling are required to extend the procedure to outdoor use. Further, we must consider whether combining liquid samples, thus increasing the volume, lowers the sensitivity of detection and produces false negatives. In this study, methods to composite bacterial spore samples from soil are demonstrated. B. subtilis spore suspensions were used as a surrogate for anthrax spores. Two soils (Arizona Test Dust and sterilized potting soil) were contaminated and spore recovery with composites was shown to match individual sample performance. Results show that dilution can be overcome by concentrating bacterial spores using standard filtration methods. This study shows that composite sampling can be a viable method of pooling samples to reduce the number of analysis that must be performed during anthrax spore remediation.     

Optimization of anthrax vaccination on the basis of rational classification of populated sites

The improved epidemiological situation requires the proper revision of the tactics used in vaccinating the population against anthrax. The important task lies in the optimization of the immunoprophylaxis of the rural population in accordance with the epizootologic situation in a given locality. To ensure correct orientation in choosing the groups of population to be vaccinated a rational classification of inhabited localities is proposed: they are classified as anthrax-free and anthrax-affected, and the latter fall into manifest, conditionally manifest, nonmanifest and unclassified. The use of the cartographic method based on this classification is recommended. The proposed vaccination tactics will allow to reduce the number of persons covered by immunoprophylaxis by 70-75%, making this coverage more exact, and to improve the epidemiological effectiveness of vaccination.     

Arundo micrantha,a new reed species for Italy,threatened in the freshwater habitat by the congeneric invasive A. donax

Arundo micrantha Lam., a reed species from southern Mediterranean area, has found in Sardinia. Its presence represents the first record for Italy and the third one for western Europe. Investigations on distribution and ecology of the Sardinian population have been carried out, with special focusing on synecology of the species. A. micrantha has found in 40 localities mainly distributed along temporary streams and permanent rivers in the central and southern part of the island. Most of Sardinian populations occurs on alluvial soils in Thermomediterranean bioclimatic context. The autonomy of Sardinian phytocoenoses was characterized with the definition of exclusive floristic taxa, biological and chorological elements, and syndinamic relationships with other assemblages. Comparing the community with other reed beds from the Mediterranean basin, a marked floristic differentiation arose between the phytocoenoses characterized by autochthonous Arundo species and those dominated by the invasive Arundo donax. Finally, management activities are proposed to ensure the conservation of this threatened autochthonous plant community in freshwater habitat.     

A longitudinal entomologic survey on the transmission of malaria in Ouagadougou (Burkina Faso)

A longitudinal entomological malaria survey was carried out in five zones of the town of Ouagadougou, Burkina Faso, and in three neighbouring villages. The main vector is Anopheles gambiae s.l. with An. funestus having a role in some localities during the dry season. Pyrethrum spray catches were carried out once or twice per month to determine variations in vector density. Inoculation rates were estimated from the number of blood-fed vectors per man and from the sporozoite rates. Larval sampling was routinely carried out all over the urban area in order to map the larval breeding sites. Widely different degrees of malaria transmission were documented in the urban area mainly related to the spatial and temporal distribution of An. gambiae larval breeding sites. Higher inoculation rates, depending both on higher vector densities and sporozoite rates, were documented in the villages.     

Carnivory in the common hippopotamus Hippopotamus amphibius: implications for the ecology and epidemiology of anthrax in African landscapes

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Convergent adaptations: bitter manioc cultivation systems in fertile anthropogenic dark earths and floodplain soils in central amazonia

SHIFTING CULTIVATION IN THE HUMID TROPICS IS INCREDIBLY DIVERSE, YET RESEARCH TENDS TO FOCUS ON ONE TYPE: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for research and debate concerning the origins, evolution, history and contemporary cultivation of bitter manioc in Amazonia and beyond.     

The distribution of two major malaria vectors, Anopheles gambiae and Anopheles arabiensis, in Nigeria.

The distribution of Anopheles gambiae and An. arabiensis across the ecological zones of Nigeria (arid savanna in the north gradually turns into humid forest in the south) was investigated. Results of the present study were compared to the distributions determined from samples of indoor-resting females reported by an earlier study over 20 years ago. Larvae were sampled in the rainy seasons of 1997 and 1999 from 24 localities, 10 of which were sampled in both years. Specimens were identified by the polymerase chain reaction method. Results showed that species composition changed significantly among the 10 localities in both years (chi2=13.62, P = 0.0002), but this change was significant in only four of the 10 localities. The identity of the prevalent (more abundant) species changed between 1997 and 1999 in only three of 10 localities. An. arabiensis was prevalent in several localities in the southern Guinea savanna, an area where it was virtually absent over 20 years ago. The data suggest that An. arabiensis has extend its range, although differences in sampling technique (larval sampling versus adult collection) can not be ruled out as a possible explanation.     

Constitution and reactivity of the organism

A new principle of somatotyping according to the set of the most informative anthropometric indices is offered. For the first time we carried out a comparative analysis of anthropometric indices of physical development, of cardiovascular system functioning and its vegetative regulation for the representatives of different somatotypes. The purpose of the analysis was to define constitutional peculiarities of adaptation reactions in young males and females to the deficiency of vital macro- and microelements in soils and drinkable water of the Southern region of Belarus. Typological specificity of organism reactivity to the unfavorable geochemical situation of the Southern region of Belarus was revealed in young males and females in different degrees of tension in adaptation processes. The suggested approach to somatotyping has allowed us to define more precisely the constitutional properties of organism reactivity in a discomfort environment.     

Ecology of two cytotypes ofButomus umbellatus III. Distribution and habitat differentiation in the Czech and Slovak Republics

The distribution, total frequency of occurrence, regional differences and habitat conditions of diploid and triploidButomus umbellatus L. were studied in the Czech and Slovak Republics. Triploids are more frequent than diploids, with numerous localities in warm lowland regions in river floodplains. Diploids were found primarily in the South Bohemian T?eboň basin, outside the warm regions. The two cytotypes do not differ in dependence on water depth. Triploids occur more in habitats with more alkaline and base-rich soils. Considering the total distribution of both cytotypes in the area studied, triploidB. umbellatus appears to be more successful than its diploid progenitor, owing to its wider habitat range and superiority in vegetative reproduction.     

A plant-geographical study of the genusDorycnium MILL. (Fabaceae) in the Czech Republic

Two species of the genusDorycnium with the most northern distribution reach the absolute northern limit of their distribution areas in the Czech Republic.Dorycnium germanicum, a less ecologically plastic and more xerothermic species, covers a compact area in south Moravia, connected with its occurrence in Lower Austria.Dorycnium herbaceum, and ecologically more tolerant species, has its primary distribution area in south-east Moravia; this is connected with the Slovak part of the area of this species; secondary occurrences are scattered throughout other parts of Moravia and Bohemia. The distribution of both species was evaluated, using 23 herbarium collections. Climatic characteristics are provided for 54 climatic and ombrometric stations from the distribution area of both species. In the Czech RepublicD. germanicum represents the Illyrian-Noric migration element whileD. herbaceum represents the Carpathian one. There is a clear climatic differentiation between the localities of both species:D. germanicum occurs in dryer and warmer regions thanD. herbaceum. An introgression, zone was identified in the vicinity of the twon of Uherské Hardi?tě and the area south-east of this town. This zone coincides with the area where most of the identification problems with these species occurred.     

Prescribed burning reduces species richness of wood-decay fungi in the forests of northwest Arkansas

The present study, which was carried out at three localities in the Ozark Mountains of northwest Arkansas, investigated the effects of prescribed burning on wood-decomposing fungi using samples of decaying woody debris (DWD) placed in plastic incubation chambers. One of the localities had not been subjected to recent prescribed burning, whereas the other localities contained both an unburned area as well as an area recently subjected to burning. In all three localities, small pieces of decaying woody debris (DWD) were collected, placed in the incubation chambers and the latter kept moist for any extended period of time. Pieces of DWD collected in the areas subjected to burning typically displayed evidence of considerable charring. Fruiting bodies appearing in the incubation chambers were removed and identified by sequencing of ribosomal DNA region. A total of 101 specimens representing 80 different taxa were recorded in the entire investigation, but the numbers of both specimens and taxa were appreciably higher for the unburned collecting sites. As such, the data obtained indicate that prescribed burning lowers the species richness of the wood-decomposing fungi associated with DWD at a particular locality. The unique aspect of the present study was the use of incubation chambers to characterize the taxa of fungi associated with CWD.     

Levels of immunoglobulins and lysozyme in 10-year-old children from different regions and the condition of the lymphatic apparatus. I. Condition of tonsils in connection with some immunological parameters and different environment

The condition of tonsils was investigated and the levels of serum IgG, IgA, IgM and lysozyme were measured in 305 ten-year-old children from three localities of the Central-Bohemian Region. The tonsils were not enlarged in 30.8% of children, in 26.2% they were enlarged, in 35.5% furrowed and in 7.5% of children tonsillectomy had been carried out. Mean levels of IgA were significantly higher in two localities in children with enlarged tonsils, insignificantly lower in children with furrowed tonsils and lowest in tonsilectomized children. The difference in the distribution of IgM levels were significant between girls with enlarged furrowed tonsils. The levels of lysozyme were not correlated with the finding in the tonsils, but a significant difference was found in the groups with enlarged tonsils between the three locailties under observation and in the groups with furrowed tonsils between two localities. The importance of the findings observed is discussed from the point of view of a possible influence of air pollution in two of the three localities under study.     

Sex-Specific Elk Resource Selection during the Anthrax Risk Period

Anthrax, caused by the spore-forming bacterium Bacillus anthracis, is a zoonosis affecting animals and humans globally. In the United States, anthrax outbreaks occur in wildlife and livestock, with frequent outbreaks in native and exotic wildlife species in Texas, livestock outbreaks in the Dakotas, and sporadic mixed outbreaks in Montana. Understanding where pathogen and host habitat selection overlap is essential for anthrax management. Resource selection and habitat use of ungulates may be sex-specific and lead to differential anthrax exposure risks across the landscape for males and females. We evaluated female elk (Cervus canadensis) resource selection in the same study areas as male elk in a previous anthrax risk study to identify risk of anthrax transmission to females and compare transmission risk between females and males. We developed a generalized linear mixed-effect model to estimate resource selection for female elk in southwest Montana during the June to August anthrax transmission risk period. We then predicted habitat selection of female and male elk across the study area and compared selection with the distribution of anthrax risk to identify spatial distributions of potential anthrax exposure for the male and female elk. Female and male elk selected different resources during the anthrax risk period, which resulted in different anthrax exposure areas for females and males. The sex-specific resource selection and habitat use could infer different areas of risk for anthrax transmission, which can improve anthrax and wildlife management and have important public health and economic implications. © 2020 The Wildlife Society.     

Sensitivity Analysis of CLIMEX Parameters in Modeling Potential Distribution of Phoenix dactylifera L.

Using CLIMEX and the Taguchi Method, a process-based niche model was developed to estimate potential distributions of Phoenix dactylifera L. (date palm), an economically important crop in many counties. Development of the model was based on both its native and invasive distribution and validation was carried out in terms of its extensive distribution in Iran. To identify model parameters having greatest influence on distribution of date palm, a sensitivity analysis was carried out. Changes in suitability were established by mapping of regions where the estimated distribution changed with parameter alterations. This facilitated the assessment of certain areas in Iran where parameter modifications impacted the most, particularly in relation to suitable and highly suitable locations. Parameter sensitivities were also evaluated by the calculation of area changes within the suitable and highly suitable categories. The low temperature limit (DV2), high temperature limit (DV3), upper optimal temperature (SM2) and high soil moisture limit (SM3) had the greatest impact on sensitivity, while other parameters showed relatively less sensitivity or were insensitive to change. For an accurate fit in species distribution models, highly sensitive parameters require more extensive research and data collection methods. Results of this study demonstrate a more cost effective method for developing date palm distribution models, an integral element in species management, and may prove useful for streamlining requirements for data collection in potential distribution modeling for other species as well.     

Chemical mapping of co-existing RNA structures.

In many cases RNA can assume co-existing or meta-stable structures preventing structure determination by chemical mapping. A novel method is described, by which RNA is modified with dimethyl sulphate without shifting the distribution of different structures. The different structures are then separated in native gel electrophoresis, and structure determination by primer extension can be carried out separately for each structure.     

Desert salt flats as oases for the spider Saltonia incerta Banks (Araneae: Dictynidae)

The deserts of southwestern North America have undergone dramatic changes over their recent geological history including large changes in size and connectivity during the Pleistocene glaciopluvial cycles. This study examines the population history of the rare spider Saltonia incerta, once thought to be extinct, to determine the role of past climatological events in shaping the structure of the species. This species is restricted to salt crusts of intermittent or dry lakes, streams or rivers in the desert southwest, a region that was much wetter during glacial periods. We examine the distribution and genetic variability of populations to test whether there is recent dispersal throughout the range of the species. Analyses of mitochondrial and nuclear DNA indicate significant population structure, with one major clade comprising New Mexico localities and one comprising California‐northern Baja California localities. Finer‐scale structure is evident within the California clade, although not all of the subclades are reciprocally monophyletic. However, isolation with migration analysis suggests that migration is very low to non‐existent. These results extend the known distribution of Saltonia, provide genetic evidence of strong isolation among localities within drainage basins and between drainage basins and provide a mechanistic understanding of population connectivity after the aridification of the American southwest. The implication is that although the species' distribution has been fragmented, populations have persisted throughout this area, suggesting that desert salt flats may have served as refugia for at least some terrestrial species.     

Analysis of In Situ Distribution of Inorganic Elements in Plants by Micro-XRF

植物的无机元素分布特征对植物生理过程具有重要的指标作用, 可揭示营养物质分布、代谢途径及毒理耐受性等多种生命过程。用微区XRF技术测试样品中无机元素的分布, 具有原位无损、可进行较大面积样品连续成像分析以及前处理过程简单等诸多优势。将微区XRF技术应用于植物样品不同器官的无机元素分布检测, 旨在探讨该技术在植物样品测试中的仪器参数选择、样品前处理方法和数据后处理手段等对测试结果的影响。为得到可靠的实验结果, 对不同含水量的器官进行不同的前处理, 并比较不同驻留时间、测试腔体真空与否等仪器条件对测试结果的影响, 同时对数据处理方法进行探索, 包括对获得的数据进行图像叠加及对不同元素浓度比例进行半定量分析。研究结果表明, 微区XRF技术测试植物样品中无机元素分布具有一定的技术优势。     

微区XRF技术分析无机元素在植物中的原位分布

植物的无机元素分布特征对植物生理过程具有重要的指标作用, 可揭示营养物质分布、代谢途径及毒理耐受性等多种生命过程。用微区XRF技术测试样品中无机元素的分布, 具有原位无损、可进行较大面积样品连续成像分析以及前处理过程简单等诸多优势。将微区XRF技术应用于植物样品不同器官的无机元素分布检测, 旨在探讨该技术在植物样品测试中的仪器参数选择、样品前处理方法和数据后处理手段等对测试结果的影响。为得到可靠的实验结果, 对不同含水量的器官进行不同的前处理, 并比较不同驻留时间、测试腔体真空与否等仪器条件对测试结果的影响, 同时对数据处理方法进行探索, 包括对获得的数据进行图像叠加及对不同元素浓度比例进行半定量分析。研究结果表明, 微区XRF技术测试植物样品中无机元素分布具有一定的技术优势。     

Anthrax explodes in an Australian summer

Anthrax occurred on 83 properties in an area of north central Victoria between 26 January and 26 March in the summer of 1997. Anthrax had not been recorded in the outbreak area since records were initiated in 1914, although anthrax did occur in the general area in the 1880s to 1890s. Standard Australian control measures were applied to the properties, including quarantine, tracing movements of animals on and off affected properties, secure disposal of carcases by burning, enhanced surveillance of stock generally in the area and the use of local disaster control procedures including an alert of health authorities. As affected property numbers began to increase dramatically from 8 February, it was decided to use blanket area vaccination to control the disease. By 26 February, the epidemic curve had returned to the base line and a buffer vaccination zone of 457 farms holding 78,649 cattle was formed by early March 1997. Between 26 January and 26 March when the outbreak was declared over, 202 cattle and 4 sheep were confirmed to have died of anthrax. Between 27 March and early November a further 26 cattle were confirmed as dying due to anthrax and 14 of these had not had previous vaccination, including four young calves and one horse. One new property within the vaccination buffer zone had an anthrax case in a cow in early November 1997. By mid-November 1997, all previously infected and all neighbouring properties within 1 km were compulsorily re-vaccinated, as were all calves when two months of age and all introduced cattle. In 1998, only two confirmed cases of anthrax were diagnosed; both were vaccinated calves on farms which had had multiple cases during the outbreak. The public reaction and attention fueled by unprecedented media attention led to intense international scrutiny from countries where anthrax is a particular zoonotic problem. Very strong representations had to be made about the safety of livestock and livestock products that came from Victoria. This event has demonstrated that there is a need to review OIE and other requirements and recommendations covering anthrax where strict restrictions are placed on livestock and livestock products to protect livestock and human populations against anthrax infection.