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1.
A hamate and the proximal part of a first metacarpal from the type locality of the Nagri Formation in Pakistan, and attributed to Sivapithecus parvada, are described. In overall proportions, the hamate is rather robust, showing most similarity to that of Gorilla. Unlike extant hominoids it lacks a well-developed hamulus, and its triquetral facet is morphologically dissimilar to that in extant anthropoids. The morphology of the hamate indicates effective weight transmission through the ulnar side of the wrist, limited ulnar deviation and restricted extension in the triquetrohamate joint, and stability of the hamatometacarpal joints. The morphology of the partial first metacarpal is most similar to that of Pan. Previously described postcranial bones of S. parvada indicate that its locomotor behaviour included both quadrupedalism and climbing. This is consistent with the limited evidence of the first metacarpal, whereas the hamate strongly emphasizes the quadrupedal aspect of the locomotor repertoire.  相似文献   
2.
Shrewsbury  M. M.  Sonek  A. 《Human Evolution》1986,1(3):233-242
Human Evolution - Four Types of precision holding in the human hand have been identified and described in accordance with the contrasting regional properties of a differentiated ungual pulp of the...  相似文献   
3.
This paper examines the relationship between the early rearing experience of zoo-born, zoo-reared chimpanzees (Pan troglodytes) and the subsequent occurrence of successful copulation as adults. Developmental histories were acquired for 71 subjects via questionnaires and phone interviews. The following variables related to aspects of chimpanzees' early rearing experience were examined: (1) Rearing conditions, that is, hand reared alone, reared with siblings or peers, or reared by at least one adult conspecific. (2) Age removed from mother. (3) Sex of subject, and/or (4) participation in shows. Each of these variables was then compared to the subjects' sexual competence, defined here as having been observed to exhibit functional copulatory behavior as adults. Seventy-five percent of the subjects were observed to exhibit functional copulatory behavior on at least one occasion. No single component of rearing was successful in producing sexually competent adults 100% of the time; no rearing condition, as defined in this study, resulted in reproductive failure for all subjects experiencing those conditions. Chimpanzees that were hand reared alone, that is, in the total absence of conspecifics, were least likely to copulate as adults; about half of those chimpanzees that were reared with siblings or peers (and in the absence of adult conspecifics) copulated as adults. Almost 90% of those chimpanzees that were reared with at least one adult conspecific copulated as adults. Chimpanzees removed from their mothers at an early age (less than one year of age) were less likely to reproduce as adults. Male and female chimpanzees were equally likely to reproduce as adults. Participation in shows or demonstrations appeared to have no effect on chimpanzees' ability to copulate as adults. © 1994 Wiley-Liss, Inc.  相似文献   
4.
In order to test for the specific therapeutic effects of thermal biofeedback (TBF) for hand warming on vascular headache (HA), 70 patients with chronic vascular HA were randomly assigned to TBF for hand warming, TBF for hand cooling, TBF for stabilization of hand temperature, or biofeedback to suppress alpha in the EEG. Patients in each condition initially had high levels of expectation of therapeutic benefit and found the treatment rationales highly credible. Participants in each condition received 12 treatment sessions on a twice-per-week basis. Based on daily HA diary data gathered for 4 weeks prior to treatment and 4 weeks after treatment, HA Index was significantly (p=.003) reduced as was HA medication consumption. There were no differential reducations in HA Index or Medication Index among the four conditions. Global self-reports of improvement gathered at the end of the post-treatment monitoring period also did not differ among the four conditions. We were unable to demonstrate a specific effect of TBF for hand warming on vascular HA activity.  相似文献   
5.
Determining the best management practices for plant invasions is a critical, but often elusive goal. Invasive removals frequently involve complex and poorly understood biotic interactions. For example, invasive species can leave potent legacies that influence the success of native species restoration efforts, and positive plant‐microbial feedbacks may promote continued reinvasion by an exotic species following restoration. Removal methods can vary in their effects on plant–soil feedbacks, with consequences for restoration of native species. We determined the effects of invasion by a leguminous shrub (French broom; Genista monspessulana) on the density and community composition of, and benefit conferred by, its microbial mutualists in its invading range. Densities of soil‐dwelling rhizobia were much higher in areas invaded by G. monspessulana relative to uninvaded areas, and this increased density of rhizobia fed back to increase seedling growth of both the invader and native legumes. We further compared how three techniques for removing G. monspessulana affected the densities of rhizobia relative to areas where G. monspessulana was still present. Removal by hand‐pulling reduced soil rhizobial densities, and reduced growth of one native legume, while having no effect on the growth of the invader. Overall, our results show that the consequences of restoration techniques, both above‐ and belowground, could be critical for the successful removal of an invasive legume and restoration of native species.  相似文献   
6.
摘要 目的:探讨股前外侧穿支皮瓣与胸腹带蒂皮瓣对手外伤组织缺损修复的应用效果及对创面愈合程度的影响。方法:选取我院2018年12月到2020年12月共收治的119例手外伤组织缺损患者作为研究对象,随机分为2组,分别为对照组(n=59,应用胸腹带蒂皮瓣修复术)和观察组(n=60,应用股前外侧穿支皮瓣修复术)。对比两组患者治疗优良率,对比两组患者治疗前后手部创面面积、创面愈合程度以及组织愈合时间,对比两组患者治疗后的Jamar握力、TAM和DASH评分情况,对比两组患者的皮瓣成活率、皮瓣危象率和血管吻合时间。结果:通过对比两组患者治疗优良率发现,观察组患者优的人数为21例、良为35例,优良率为93.33%,对照组患者优的人数为16例,良为30例,优良率为77.97%,观察组高于对照组(P<0.05);治疗后,与对照组相比,观察组患者的手部创面面积、组织愈合时间和DASH评分显著减少,创面愈合程度以及TAM与Jamar握力显著增加(P<0.05);通过对比两组患者的皮瓣成活率、术后皮瓣危象率以及血管吻合时间发现,两组患者的术后皮瓣危象率、血管吻合时间对比无明显差异(P>0.05),两组患者的术后皮瓣成活率对比差异显著,观察组明显高于对照组(P<0.05)。结论:对手外伤组织缺损患者应用股前外侧穿支皮瓣与胸腹带蒂皮瓣修复术均具有明显的修复效果,但是应用股前外侧穿支皮瓣能够提升治疗效果,提升患者创面愈合程度减少愈合时间,提升患者手部运动情况,提升术后皮瓣成活率,值得临床应用推广。  相似文献   
7.
Miro is a highly conserved calcium‐binding GTPase at the regulatory nexus of mitochondrial transport and autophagy. Here we present crystal structures comprising the tandem EF hand and carboxy terminal GTPase (cGTPase) domains of Drosophila Miro. The structures reveal two previously unidentified ‘hidden’ EF hands, each paired with a canonical EF hand. Each EF hand pair is bound to a helix that structurally mimics an EF hand ligand. A key nucleotide‐sensing element and a Pink1 phosphorylation site both lie within an extensive EF hand–cGTPase interface. Our results indicate structural mechanisms for calcium, nucleotide and phosphorylation‐dependent regulation of mitochondrial function by Miro.  相似文献   
8.
The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants'' own hidden hand is touched. If the viewed and felt touches are given at the same time then this is sufficient to induce the compelling experience that the rubber hand is one''s own hand. The RHI can be used to investigate exactly how the brain constructs distinct body representations for one''s own body. Such representations are crucial for successful interactions with the external world. To obtain a subjective measure of the RHI, researchers typically ask participants to rate statements such as "I felt as if the rubber hand were my hand". Here we demonstrate how the crossmodal congruency task can be used to obtain an objective behavioral measure within this paradigm.The variant of the crossmodal congruency task we employ involves the presentation of tactile targets and visual distractors. Targets and distractors are spatially congruent (i.e. same finger) on some trials and incongruent (i.e. different finger) on others. The difference in performance between incongruent and congruent trials - the crossmodal congruency effect (CCE) - indexes multisensory interactions. Importantly, the CCE is modulated both by viewing a hand as well as the synchrony of viewed and felt touch which are both crucial factors for the RHI.The use of the crossmodal congruency task within the RHI paradigm has several advantages. It is a simple behavioral measure which can be repeated many times and which can be obtained during the illusion while participants view the artificial hand. Furthermore, this measure is not susceptible to observer and experimenter biases. The combination of the RHI paradigm with the crossmodal congruency task allows in particular for the investigation of multisensory processes which are critical for modulations of body representations as in the RHI.  相似文献   
9.
It has not been established whether the smallest perceptible change in the intensity of vibrotactile stimuli depends on the somatosensory channel mediating the sensation. This study investigated intensity difference thresholds for vibration using contact conditions (different frequencies, magnitudes, contact areas, body locations) selected so that perception would be mediated by more than one psychophysical channel. It was hypothesized that difference thresholds mediated by the non-Pacinian I (NPI) channel and the Pacinian (P) channel would differ. Using two different contactors (1-mm diameter contactor with 1-mm gap to a fixed surround; 10-mm diameter contactor with 2-mm gap to the surround) vibration was applied to the thenar eminence and the volar forearm at two frequencies (10 and 125?Hz). The up-down-transformed-response method with a three-down-one-up rule provided absolute thresholds and also difference thresholds at various levels above the absolute thresholds of 12 subjects (i.e., sensation levels, SLs) selected to activate preferentially either single channels or multiple channels. Median difference thresholds varied from 0.20 (thenar eminence with 125-Hz vibration at 10?dB SL) to 0.58 (thenar eminence with 10-Hz vibration at 20?dB SL). Median difference thresholds tended to be lower for the P channel than the NPI channel. The NPII channel may have reduced difference thresholds with the smaller contactor at 125?Hz. It is concluded that there are large and systematic variations in difference thresholds associated with the frequency, the magnitude, the area of contact, and the location of contact with vibrotactile stimuli that cannot be explained without increased understanding of the perception of supra-threshold vibrotactile stimuli.  相似文献   
10.
《Ostrich》2013,84(3):271-272
The Berlese funnel method, and its variations, is commonly used for the extraction of arthropods from various substrates such as nest material. However, little is known about its effectivity in extracting ectoparasites from penguin nests. This study aimed to assess the efficacy of a modified Berlese funnel method in extracting ectoparasites from African Penguin Spheniscus demersus nests and to determine differences in extraction capacity across parasite taxa and life stages. African Penguin nests (n = 278) were sampled at five penguin colonies along the south-west coast of South Africa in 2017. Nest samples were subjected to a modified Berlese funnel method with naphthalene as a repellent. Thereafter, all remaining ectoparasites were removed by hand sorting. Ectoparasite abundance was positively correlated between the two extraction methods (Spearman’s r = 0.73–0.89). Compared to total counts, flea (combined life stages and larvae) and total ectoparasite abundance and prevalence were significantly lower with the modified Berlese funnel method. In addition, adult flea and tick prevalence (but not abundance) was significantly lower with the modified Berlese funnel method compared with total counts. The modified Berlese funnel method fails as a quantitative method and can only provide a crude indication of the incidence of ectoparasites in penguin nests.  相似文献   
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