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31.
Mental conditions usually affect cognitive, emotional and volitional aspects and functions of the personality, which are also functions of interest in law, as they are essential at the time of adjudicating guilt, labeling the accused a criminal, and proffering a sentence. A relationship between mental illness and criminality has, thus, been described and given as one of the reasons for the large number of mental patients in prisons. Whether this relationship is one of causality or one that flows through many other variables is a matter of debate, but there is no debating that prisons have become a de facto part, and an important one, of mental health systems in many countries. This paper deals with the issue of the relationship and provides estimates of prevalence of mental patients in prisons culled from many studies in different countries. It also provides some direction for the management of mental patients as they crowd correctional systems.  相似文献   
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The mimicry of malpighiaceous oil‐flowers appears to be a recurrent pollination strategy among many orchids of the subtribe Oncidiinae. These two plant groups are mainly pollinated by oil‐gathering bees, which also specialize in pollen collection by buzzing. In the present study, the floral ecology of the rewardless orchid Tolumnia guibertiana (Oncidiinae) was studied for the first time. The orchid was self‐incompatible and completely dependent on oil‐gathering female bees (Centris poecila) for fruit production. This bee species was also the pollinator of two other yellow‐flowered plants in the area: the pollen and oil producing Stigmaphyllon diversifolium (Malpighiaceae) and the polliniferous and buzzing‐pollinated Ouratea agrophylla (Ochnaceae). To evaluate whether this system is a case of mimetism, we observed pollinator visits to flowers of the three plant species and compared the floral morphometrics of these flowers. The behavior, preferences and movement patterns of Centris bees among these plants, as well as the morphological data, suggest that, as previously thought, flowers of T. guibertiana mimic the Malpighiaceae S. diversifolium. However, orchid pollination in one of the studied populations appears to depend also on the presence of O. agrophylla. Moreover, at the two studied populations, male and female pollination successes of T. guibertiana were not affected by its own floral display, and did not differ between populations. The results are discussed in relation to the behavior and preferences of Centris bees, as well as the differential presence and influence of each of the two floral models.  相似文献   
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We perform phylogenetic analyses of the ‘polymorphic earless praying mantises’, a heterogeneous assemblage comprising c. 55% of mantodean diversity in the Neotropics. Bayesian and maximum‐likelihood were implemented on a DNA dataset of 9949 aligned nucleic acid characters comprising ten mitochondrial and nuclear genes. Our analyses largely resolved congruent relationships with high levels of support for higher‐level taxonomic groups, but revealed extensive inconsistencies between the resolved topology and morphology‐based classification systems. The polymorphic earless praying mantises, now granted superfamily status as the Acanthopoidea stat. n., comprises 8 families, 15 subfamilies and 18 tribes. Our newly revised organization required the following taxonomic changes: (i) Thespidae sensu n., including subfamilies Pseudopogonogastrinae subfam. n., Pseudomiopteryginae sensu n., Bantiinae subfam. n., Miobantiinae sensu n. and Thespinae sensu n. (tribes Musoniellini trib. n. and Thespini sensu n. ); (ii) Angelidae stat. n. et sensu n. ; (iii) Coptopterygidae stat. n. ; (iv) Liturgusidae sensu n. ; (v) Photinaidae stat. n., including Macromantinae stat. n., Cardiopterinae stat. n., Photiomantinae subfam. n. and Photinainae sensu n. (tribes Microphotinini trib. n., Orthoderellini stat. n. and Photinaini sensu n. ); (vi) Stenophyllidae stat. n. ; (vii) Acontistidae stat. n. ; and (viii) Acanthopidae sensu n. Our new system also resulted in the reassignment of various genera to new and existing higher‐level taxa, the exclusion of old world genera otherwise traditionally classified among the Thespidae, Liturgusidae and Angelidae, the confirmation of Stenophylla Westwood as member of this clade, and the revalidation of Paradiabantia Piza stat. r. We provide diagnoses for all suprageneric taxa using external morphological characters and male genitalia. A key to higher‐level groups is provided. We incorporate egg case structural variation as a novel approach for taxon delineation. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:29E37322‐30EB‐4F64‐80C9‐E2149B5B0195 .  相似文献   
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The tuco-tucos [Ctenomys) are subterranean rodents that are widespread in southern South America. On the basis of its 60 living species, Ctenomys is one of the most speciose mammalian genera and displays great chromosomal variation. In order to study the mode of speciation in Ctenomys and to evaluate the role of chromosomes in cladogenesis, it is essential to generate an accurate phylogeny of the genus. From such a phylogeny it should be possible to identify particular species lineages worthy of further study. Following the success in 1998 of Lessa & Cook in generating a phylogeny of 10, mostly Bolivian, species from mitochondrial cytochrome b sequences, we sequenced a further 18, mostly Argentinian, species. By combining our datasi't with that of Lcssa & Cook's we were able to confirm six species lineages within Ctenomys. These lineages correspond well to taxonomic groups suggested on the basis of morphology and biogeographv. At least two of the species groups (the Boliviano-Matogrossense and Chaco) arc very variable chromosomally, and are worthwhile systems to examine the possibility of chromosomal spec iation. While, in general, multiple specimens of the named species did form monophyletic groups on the basis of the cytochrome b analysis, there were some exceptions. Thus, C. bergi and C yolandae did not form separate clades in the phylogenetic analysis, nor did C. roigi and C. dorbignyi. The molecular analysis was also very informative with regards species designations for C. boliviensis and related forms.  相似文献   
37.
Climate increases regional tree-growth variability in Iberian pine forests   总被引:3,自引:0,他引:3  
Tree populations located at the geographical distribution limit of the species may provide valuable information about tree‐growth response to changes on climatic conditions. We established nine Pinus nigra, 12 P. sylvestris and 17 P. uncinata tree‐ring width chronologies along the eastern and northern Iberian Peninsula, where these species are found at the edge of their natural range. Tree‐growth variability was analyzed using principal component analysis (PCA) for the period 1885–1992. Despite the diversity of species, habitats and climatic regimes, a common macroclimatic signal expressed by the first principal component (PC1) was found. Moreover, considering the PC1 scores as a regional chronology, significant relations were established with Spanish meteorological data. The shared variance held by the tree chronologies, the frequency of narrow rings and the interannual growth variability (sensitivity) increased markedly during the studied period. This shows an enhancement of growth synchrony among forests indicating that climate might have become more limiting to growth. Noticeably, an upward abrupt shift in common variability at the end of the first half of the 20th century was detected. On the other hand, moving‐interval response functions showed a change in the growth–climate relationships during the same period. The relationship between growth and late summer/autumn temperatures of the year before growth (August–September, negative correlation, and November, positive correlation) became stronger. Hence, water stress increase during late summer previous to tree growth could be linked to the larger growth synchrony among sites, suggesting that climate was driving the growth pattern changes. This agrees with the upward trend in temperature observed in these months. Moreover, the higher occurrence of extreme years and the sensitivity increase in the second half of the 20th century were in agreement with an increment in precipitation variability during the growing period. Precipitation variability was positively related to tree‐growth variability, but negatively to radial growth. In conclusion, a change in tree‐growth pattern and in the climatic response of the studied forests was detected since the mid‐20th century and linked to an increase in water stress. These temporal trends were in agreement with the observed increase in warmer conditions and in precipitation variability.  相似文献   
38.
This article explores the student resistances that shape orientations to schooling. Drawing on a study of Latina/o youth, I examine how race and gender influence whether they perceive education as oppressive or useful in resisting oppression. The key lever that may alter their perceptions is how school and society treat Latinos differently from Latinas. This study shows how ethnography can inspire pedagogical practices that bolster urban students' resistances to the oppressive forces negatively impacting their education. [Latina/o youth, race, gender, resistance, urban education]  相似文献   
39.
ABSTRACT. We recently reported the isolation of a leptomyxid ameba from the brain of a mandrill baboon that died of meningo-encephalitis. Based on light and electron microscopic studies, animal pathogenicity tests, and immunofluorescence patterns, we conclude that our isolate differs fundamentally from the other two amebas ( Leptomyxa and Gephyramoeba ) included in the Order Leptomyxida. We therefore created a new genus, Balamuthia , to accommodate our isolate and described it as Balamuthia mandrillaris to reflect the origin of the type species. Briefly, B. mandrillaris is a pathogenic ameba that causes amebic encephalitis in humans and animals. It has trophic and cyst stages in its life cycle, and is uninucleate with a large vesicular nucleus and a central nucleolus. Mature cysts have a tripartite wall consisting of an outer loose ectocyst, an inner endocyst and a middle mesocyst. Unlike Acanthamoeba and Naegleria , the other two amebas that cause amebic encephalitis in humans, Balamuthia will not grow on agar plates seeded with enteric bacteria. However, Balamuthia grows on a variety of mammalian cell cultures and kills mice following intranasal or intraperitoneal inoculation. Based on immunofluorescence testing, 35 cases of amebic encephalitis in humans and three in other animals have been identified worldwide as being caused by Balamuthia .  相似文献   
40.
A total of 46 populations belonging to the genus Coincya Ruoy (Brassicaceae) from the Iberian Peninsula was examined for their wax ester fatty acids composition. Size of ester fatty acids in the genus Coincya varies between 14 and 28 carbon atoms. This series is dominated by acids with an even number of carbon atoms. The most abundant acids are Ojg, C^y, C^^o and C26 among evens and C17 and C21 among odds. A positive correlation was observed between chemical composition and environmental adaptation, and also with certain morphological characters. Changes relate to low temperatures or to high relative humidity, and there is a positive correlation between chemical composition and leaf glaucousness.  相似文献   
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