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291.
The small, basically Oriental family Opisotretidae is rediagnosed, reclassified, and shown to comprise the following seven genera, all keyed: Carlotretus Hoffman, 1980, with two species, including Carlotretus triramus sp. n. from southern China; Corypholophus Attems, 1938, with two species, one in Vietnam, the other in the Ryukyus, Japan; Martensodesmus Golovatch, 1987, with eight species, all keyed, including Martensodesmus cattienensis sp. n. from southern Vietnam, as well as Martensodesmus bedosae sp. n. and Martensodesmus spiniger sp. n. from southern China; Opisotretus Attems, 1907, with seven species, all keyed, including Opisotretus beroni sp. n. and Opisotretus hagen sp. n., both from Papua New Guinea, Opisotretus deharvengi sp. n. from Sulawesi, Indonesia, and Opisotretus spinosus sp. n. from Nusakambangan Island, off Java, Indonesia; Opisthoporodesmus Silvestri, 1899, with six nominate species; Retrodesmus Chamberlin, 1945, with two species, i.e. the type-species Retrodesmus dammermani Chamberlin, 1945, from Java, Indonesia, revised from the holotype, and Retrodesmus cavernicola sp. n., from Papua New Guinea; and Solaenaulus Attems, 1940, with two species. Comments are presented on the family’s possible relationships and palaeogeographic history. Instead of being considered as the sole component of the superfamily Opisotretoidea, the Opisotretidae is believed here to form one of the families of the diverse superfamily Trichopolydesmoidea, perhaps the sister-group to, if not immediately derived from, the pantropical family Fuhrmannodesmidae. The origin of Opisotretidae, previously dated as far back as the Triassic (220 Ma) in relation to the fragmentation of eastern Gondwanaland, mainly in the region of present-day Indonesia, could have had nothing to do with Gondwanaland. Opisotretids might have originated in mainland Southeast Asia well within the Cenozoic, with subsequent dispersals along the Himalayas in the West and across Indonesia (including New Guinea) in the East, also reaching as far north as the Ryukyus, Japan and Guangxi, southern China.  相似文献   
292.

Introduction

We used a multidimensional approach to study isometric force control in single and dual-task conditions.

Methods

Multiple measures of performance, efficiency, variability, and structural interference were calculated at low and higher force levels under single (force maintenance) and dual-task (force maintenance and reaction time) conditions.

Results

Reaction time and signal-to-noise ratio were larger in the dual-task conditions. They were also greater for the higher force condition, while sample entropy was lower. Perturbation analyses revealed smaller relative amplitude of downward perturbations for the higher force level.

Discussion

Attentional effort and efficiency are positively related when force level increases, and inversely related to entropy. These relations were presumably mediated by attentional investment. Behavioral perturbations show that attentional resources and structural interference models are not mutually exclusive to account for dual-task situation. Overall, the present study highlights the interest of a multidimensional assessment of force control.  相似文献   
293.
In the early nineteen sixties, Arambourg and Magnier found some freshwater fish (i.e., Polypterus sp., Siluriformes indet. and Lates sp.) mixed with marine members in an Eocene vertebrate assemblage at Gebel Coquin, in the southern Libyan Desert. This locality, aged ca 37–39Ma and now known under the name of Dur At-Talah, has been recently excavated. A new fish assemblage, mostly composed of teeth, was collected by the Mission Paléontologique Franco-Libyenne. In this paper, we describe freshwater fish members including a dipnoan (Protopterus sp.), and several actinopterygians: bichir (Polypterus sp.), aba fish (Gymnarchus sp.), several catfishes (Chrysichthys sp. and a mochokid indet.), several characiforms (including the tiger fish Hydrocynus sp., and one or two alestin-like fish), and perciforms (including the snake-head fish Parachanna sp. and at least one cichlid). Together with the fossiliferous outcrops at Birket Qarun in Egypt, the Libyan site at Dur At-Talah reduces a 10-Ma chronological gap in the fossil record of African freshwater fish. Their fish assemblages overlap in their composition and thus constitute a rather homogenous, original and significant amount of new elements regarding the Paleogene African ichthyofauna. This supports the establishment of the modern African freshwater fish fauna during this time period because these sites mostly contain the earliest members known in modern genera.  相似文献   
294.
Isernia La Pineta (south-central Italy, Molise) is one of the most important archaeological localities of the Middle Pleistocene in Western Europe. It is an extensive open-air site with abundant lithic industry and faunal remains distributed across four stratified archaeosurfaces that have been found in two sectors of the excavation (3c, 3a, 3s10 in sect. I; 3a in sect. II). The prehistoric attendance was close to a wet environment, with a series of small waterfalls and lakes associated to calcareous tufa deposits. An isolated human deciduous incisor (labelled IS42) was discovered in 2014 within the archaeological level 3 coll (overlying layer 3a) that, according to new 40Ar/39Ar measurements, is dated to about 583–561 ka, i.e. to the end of marine isotope stage (MIS) 15. Thus, the tooth is currently the oldest human fossil specimen in Italy; it is an important addition to the scanty European fossil record of the Middle Pleistocene, being associated with a lithic assemblage of local raw materials (flint and limestone) characterized by the absence of handaxes and reduction strategies primarily aimed at the production of small/medium-sized flakes. The faunal assemblage is dominated by ungulates often bearing cut marks. Combining chronology with the archaeological evidence, Isernia La Pineta exhibits a delay in the appearance of handaxes with respect to other European Palaeolithic sites of the Middle Pleistocene. Interestingly, this observation matches the persistence of archaic morphological features shown by the human calvarium from the Middle Pleistocene site of Ceprano, not far from Isernia (south-central Italy, Latium). In this perspective, our analysis is aimed to evaluate morphological features occurring in IS42.  相似文献   
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296.

Background

In case of outbreak of rash illness in remote areas, clinically discriminating monkeypox (MPX) from severe form of chickenpox and from smallpox remains a concern for first responders.

Objective

The goal of the study was therefore to use MPX and chickenpox outbreaks in Democratic Republic of Congo (DRC) as a test case for establishing a rapid and specific diagnosis in affected remote areas.

Methods

In 2008 and 2009, successive outbreaks of presumed MPX skin rash were reported in Bena Tshiadi, Yangala and Ndesha healthcare districts of the West Kasai province (DRC). Specimens consisting of liquid vesicle dried on filter papers or crusted scabs from healing patients were sampled by first responders. A field analytical facility was deployed nearby in order to carry out a real-time PCR (qPCR) assay using genus consensus primers, consensus orthopoxvirus (OPV) and smallpox-specific probes spanning over the 14 kD fusion protein encoding gene. A PCR-restriction fragment length polymorphism was used on-site as backup method to confirm the presence of monkeypox virus (MPXV) in samples. To complete the differential diagnosis of skin rash, chickenpox was tested in parallel using a commercial qPCR assay. In a post-deployment step, a MPXV-specific pyrosequencing was carried out on all biotinylated amplicons generated on-site in order to confirm the on-site results.

Results

Whereas MPXV proved to be the agent causing the rash illness outbreak in the Bena Tshiadi, VZV was the causative agent of the disease in Yangala and Ndesha districts. In addition, each on-site result was later confirmed by MPXV-specific pyrosequencing analysis without any discrepancy.

Conclusion

This experience of rapid on-site dual use DNA-based differential diagnosis of rash illnesses demonstrates the potential of combining tests specifically identifying bioterrorism agents and agents causing natural outbreaks. This opens the way to rapid on-site DNA-based identification of a broad spectrum of causative agents in remote areas.  相似文献   
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For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (s.l.) associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of Khoratpithecus, increasing thereby the Miocene diversity of southern Asian hominoids. The composition of the associated fauna as well as stable isotope data on Hipparion (s.l.) indicate that it inhabited an evergreen forest in a C3-plant environment. Our results enlighten that late Miocene hominoids were more regionally diversified than other large mammals, pointing towards regionally-bounded evolution of the representatives of this group in Southeast Asia. The Irrawaddy Formation, with its extensive outcrops and long temporal range, has a great potential for improving our knowledge of hominoid evolution in Asia.  相似文献   
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