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Although adult Lepidoptera are not often considered medically relevant, some butterflies and moths are notorious for their consumption of mammalian body fluids. These Lepidoptera can be blood‐feeding (hematophagous), tear‐feeding (lachryphagous), or sweat‐feeding (we use the term “sudophagous”). Blood‐feeding Lepidoptera have been observed piercing the skin of their hosts during feeding, while tear‐feeding Lepidoptera have been observed frequenting the eyes of hosts in order to directly obtain lachrymal fluid. These behaviors have negative human health implications and some potential for disease transmission. In this study, articles concerning feeding behavior of blood, sweat, and tear‐feeding Lepidoptera were reviewed, with emphasis on correlations between morphological characters and feeding behaviors. Harmful effects and vector potential of these Lepidoptera are presented and discussed.  相似文献   

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Abstract

In the first decade of the 21st Century, calls for interdisciplinary research are commonplace. Yet, relatively few papers discuss how to complete such research successfully. In this paper, I describe the details of data collection focused on five, six and seven‐year old children. The project examined the effect of environmental contaminants on children's educational outcomes. It included a primary caregiver interview, a skill test with the child, and a venous blood draw from the child to test for lead, mercury, cadmium, arsenic, nicotine, and cotinine. This paper describes key issues and the solutions I adopted. Challenges discussed here include navigating the Institutional Review Board Process, analyzing the blood, obtaining the supplies needed to draw blood, banking blood for future research, hiring a phlebotomist, and recruiting subjects. While not all details will apply directly to other research projects, this paper provides some perspective on the current realities facing social scientists who decide to collect biological samples.  相似文献   

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In this article, I seek to show how states of insecurity provoked by ongoing social, economic, and political ruptures in Haiti can disorder individual subjectivity and generate the flight of individuals seeking asylum within and across borders. Nongovernmental actors working in Haiti and with Haitians in the diaspora frequently managed the long-term psychosocial effects of insecurity. Their interventions can range from repressive to compassionate and influence the formation of identity and the embodied experiences of trauma for vulnerable Haitians. The case of a young Haitian refugee who was repatriated to Haiti from the United States in the 1990s demonstrates how insecurity is both an existential state reflecting the disordering of embodied experience, as well as a collective sociopolitical condition the effects of which cannot be managed or contained within national borders. The case is emblematic of the plight of thousands of Haitians affected by the January 12, 2010, earthquake.  相似文献   

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《Journal of bryology》2013,35(4):283-287
Abstract

Following revision of Dendroceros specimens from West Africa and South Atlantic islands, three species are recognized for this geographical area: Dendroceros adglutinatus, D. africanus and finally D. herasii which is described as new. On the other hand, D. crispatus is excluded from Africa while Folioceros fuciformis (Megaceros lacerus, Anthoceros fuciformis) is excluded from Equatorial Guinea. A preliminary key to the five Dendroceros species known to occur in Africa is included.  相似文献   

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Coral Reefs - Characterizing deep-sea coral biodiversity is essential to evaluate the current state of deep-sea ecosystems and to assess vulnerability to anthropogenic threats such as offshore...  相似文献   

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Two new species of Gnathostomulida from Bermuda and one from North Carolina are described. All belong to the higher Bursovaginoidae with two occurring in the genus Austrognathia and one in the genus Gnathostomula. Tables of major diagnostic characters showing morphological variability within species and between previously described species in the same genus are included. Clarification in recognition of Gnathostomula jenneri and Gnathostomula brunidens is given under “Remarks on Known Species”.  相似文献   

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T.M.R. Houlton  B.K. Billings 《HOMO》2017,68(5):362-377
This paper addresses the history, composition and scientific value of one of the most comprehensive facemask collections in Africa, the Raymond A. Dart Collection of African Life and Death Masks. Housed within the School of Anatomical Sciences at the University of the Witwatersrand (South Africa), it comprises 1110 masks (397 life, 487 death, 226 unknown). Life masks represent populations throughout Africa; death masks predominately southern Africa. Males preponderate by 75%. Recorded ages are error prone, but suggest most life masks are those of <35 year-olds, death masks of 36+ year-olds. A total of 241 masks have associated skeletons, 209 presenting a complete skull.Life masks date between 1927 and c.1980s, death masks 1933 and 1963. This historical collection presents uncanny associations with outmoded typological and evolutionary theories. Once perceived an essential scientific resource, performed craniofacial superimpositions identify the nose as the only stable feature maintained, with the remaining face best preserved in young individuals with minimal body fat. The facemask collection is most viable for teaching and research within the history of science, specifically physical anthropology, and presents some value to craniofacial identification. Future research will have to be conducted with appropriate ethical considerations to science and medicine.  相似文献   

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Beards, baldness, and sweat secretion   总被引:2,自引:0,他引:2  
The hypothesis according to which male common baldness has developed in the human species as a compensation for the growth of a beard in order to achieve heat loss has been tested. In 100 clean-shaven men direct measurement of the area of glabrous skin on the forehead and calvaria was found to be proportional to that of the hairy skin on the lips, cheeks, chin and neck. During light hyperthermia the evaporation rate on the bald scalp was 2 to 3 times higher than on the hairy scalp. Conversely the evaporation rate was practically equal on the foreheads and chins of women and unbearded young men, while in adult clean-shaven bearded men it was 40% less on the chin than the forehead. These results support the hypothesis that male baldness is a thermoregulatory compensation for the growth of a beard in adults.  相似文献   

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Peptide sr11a was purified from the venom of Conus spurius, a vermivorous cone snail collected in the Yucatan Channel, in the Western Atlantic. Its primary structure was determined by automatic Edman degradation after reduction and alkylation. Its molecular mass, as determined by MALDI-TOF mass spectrometry (average mass 3650.77 Da), confirmed the chemical data (calculated average mass, 3651.13 Da). The sequence of peptide sr11a (CRTEGMSCgamma gamma NQQCCWRSCCRGECEAPCRFGP&; gamma, gamma-carboxy-Glu; &, amidated C-terminus) shows eight Cys residues arranged in the pattern that defines the I-superfamily of conotoxins. Peptide sr11a contains two gamma-carboxy-Glu residues, a post-translational modification that has been found in other I-conotoxins from species that live in the West Pacific: r11e from the piscivorous Conus radiatus, and kappa-BtX from the vermivorous Conus betulinus. Peptide sr11a is the eighth I-conotoxin isolated from a Conus venom and the first I-conotoxin from a species from the Western Atlantic. Peptide sr11a produced stiffening of body, limbs and tail when injected intracranially into mice.  相似文献   

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The biological function of anatomical specializations in the mechanosensory lateral line of elasmobranch fishes is essentially unknown. The gross and histological features of the lateral line in the Atlantic stingray, Dasyatis sabina, were examined with special reference to its role in the localization and capture of natural invertebrate prey. Superficial neuromasts are arranged in bilateral rows near the dorsal midline from the spiracle to the posterior body disk and in a lateral position along the entire length of the tail. All dorsal lateral line canals are pored, contain sensory neuromasts, and have accessory lateral tubules that most likely function to increase their receptive field. The pored ventral canal system consists of the lateral hyomandibular canal along the disk margin and the short, separate mandibular canal on the lower jaw. The extensive nonpored and relatively compliant ventral infraorbital, supraorbital, and medial hyomandibular canals form a continuous complex on the snout, around the mouth, and along the abdomen. Vesicles of Savi are small mechanosensory subdermal pouches that occur in bilateral rows only along the ventral midline of the rostrum. Superficial neuromasts are best positioned to detect water movements along the transverse body axis such as those produced by tidal currents, conspecifics, or predators. The pored dorsal canal system is positioned to detect water movements created by conspecifics, predators, or possibly distortions in the flow field during swimming. Based upon the stingray lateral line morphology and feeding behavior, we propose the Mechanotactile Hypothesis, which states that the ventral nonpored canals and vesicles of Savi function as specialized tactile mechanoreceptors that facilitate the detection and capture of small benthic invertebrate prey. J. Morphol. 238:1–22, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

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Blood volume, the venous system, preload, and cardiac output   总被引:7,自引:0,他引:7  
Cardiac output is determined by heart rate, by contractility (maximum systolic elastance, Emax) and afterload, and by diastolic ventricular compliance and preload. These relationships are illustrated using the pressure-volume loop. Diastolic compliance and Emax place limits determined by the heart within which the pressure-volume loop must lie. End-diastolic and end-systolic pressures and hence the exact position of the loop within these limits are determined by the peripheral circulation. In the presence of minimal sympathetic tone, some 60% of total blood volume is hemodynamically inactive and constitutes a blood volume reserve (the unstressed volume). The remainder of the blood volume (the stressed volume) and the compliance of the venous system determine the venous pressure. This venous pressure together with venous resistance determines venous return, right atrial pressure, cardiac preload, and hence cardiac output. Venoconstriction causes conversion of unstressed volume to the stressed volume, the blood volume reserve is converted into hemodynamically active blood volume. After hemorrhage this replaces the lost stressed volume, while in other situations where total blood volume is not reduced, it allows a sustained increase in cardiac output. The major blood volume reserve is in the splanchnic bed: the liver and intestine, and in animals but not man, the spleen. A major unsolved problem is how the conversion of unstressed volume to stressed volume by venoconstriction is reflexly controlled.  相似文献   

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This study investigates the effects of a short-term aerobic training program in a hot environment on thermoregulation, blood parameters, sweat secretion and composition in tropic-dwellers who have been exposed to passive heat. Sixteen healthy Malaysian-Malay male volunteers underwent heat acclimation (HA) by exercising on a bicycle ergometer at 60% of VO2max for 60 min each day in a hot environment (Ta: 31.1+/-0.1 degrees C, rh: 70.0+/-4.4%) for 14 days. All parameters mentioned above were recorded on Day 1 and at the end of HA (Day 16). On these two days, subjects rested for 10 min, then cycled at 60% of VO2max for 60 min and rested again for 20 min (recovery) in an improvised heat chamber. Rectal temperature (Tre), mean skin temperature (Tsk) heart rate (HR), ratings of perceived exertion (RPE), thermal sensation (TS), local sweat rate and percent dehydration were recorded during the test. Sweat concentration was analysed for sodium [Na+]sweat and potassium. Blood samples were analysed for biochemical changes, electrolytes and hematologic indices. Urine samples were collected before and after each test and analysed for electrolytes.After the period of acclimation the percent dehydration during exercise significantly increased from 1.77+/-0.09% (Day 1) to 2.14+/-0.07% (Day 16). Resting levels of hemoglobin, hematocrit and red blood cells decreased significantly while [Na+]sweat increased significantly. For Tre and Tsk there were no differences at rest. Tre, HR, RPE, TS, plasma lactate concentration, hemoglobin and hematocrit at the 40th min of exercise were significantly lower after the period of acclimation but mean corpuscular hemoglobin and serum osmolality were significantly higher while no difference was seen in [Na+]sweat and Tsk. It can be concluded that tropic-dwelling subjects, although exposed to prolonged passive heat exposure, were not fully heat acclimatized. To achieve further HA, they should gradually expose themselves to exercise-heat stress in a hot environment.  相似文献   

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The detection of West Nile virus (WNV) nucleic acid in a blood donation from Vienna, Austria, as well as in Culex pipiens pupae and egg rafts, sampled close to the donor’s residence, is reported. Complete genomic sequences of the human- and mosquito-derived viruses were established, genetically compared and phylogenetically analyzed. The viruses were not identical, but closely related to each other and to recent Czech and Italian isolates, indicating co-circulation of related WNV strains within a confined geographic area. The detection of WNV in a blood donation originating from an area with low WNV prevalence in humans (only three serologically diagnosed cases between 2008 and 2014) is surprising and emphasizes the importance of WNV nucleic acid testing of blood donations even in such areas, along with active mosquito surveillance programs.  相似文献   

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