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Niu  Lili  Guo  Yanchen  Lin  Zhengrong  Shi  Zhe  Bian  Tianyuan  Qi  Lin  Meng  Long  Grace  Anthony A.  Zheng  Hairong  Yuan  Ti-Fei 《中国科学:生命科学英文版》2020,63(9):1328-1336
Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.  相似文献   
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This article explores the material practices through which lower-caste and poor villagers engage with bureaucracy in contemporary India. We take documents and paperwork – such as ration cards and community certificates – as a ‘lens’ through which to explore how paper materiality is infused with the politics of power, patronage, and identity. The article brings ethnography from rural Tamil Nadu, South India, in conversation with two bodies of literature: one on the materiality of bureaucracy and one on the nature of political mediation in contemporary India. We demonstrate how everyday engagements with paperwork as well as processes of applying, form filling, and securing recommendations are constitutive of social and political relationships and, ultimately, of citizenship itself. Political mediation around paperwork and bureaucracy generates a hierarchy of citizens rather than equal citizenship for all, yet ordinary villagers transpire as anything but passive. Drawing on patronage networks, engaging in affective performances, and navigating a politics of identity, they actively negotiate access to the state in an attempt to claim their rights as citizens.  相似文献   
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Coral Reefs - A correction to this paper has been published: https://doi.org/10.1007/s00338-021-02111-z  相似文献   
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The southern Persian/Arabian Gulf experiences extreme seasonal temperature variation (> 20 °C) making it among the most hostile reef environments on Earth. Previous anecdotal evidence has suggested that seasonal temperature changes may influence regional reef fish assemblages, but to date research has been limited. To examine the influence of temperature on reef fish abundance and composition, we performed visual surveys in summer and in winter over three years at three reefs in the southern Gulf (Dhabiya, Saadiyat and Ras Ghanada). Overall abundance of fishes was 40% higher in summer than in winter, and multivariate analyses showed strong and significant differences in overall seasonal community structure, consistent at all sites and across all years. Seasonal differences were largely driven by nine of the 30 observed species, which together accounted for 70% of the divergence in community structure between summer and winter. Of these nine species, Lutjanus ehrenbergii, Lutjanus fulviflamma, Plectorhinchus sordidus and Abudefduf vaigiensis were significantly more abundant in summer, Parupeneus margaritatus and Acanthopagrus bifasciatus, were significantly more common on reefs in winter. We discuss these changes in terms of seasonal physiological and ecological constraints, and explore the implications of these changes on the functional ecology of reef fishes in this thermally variable and extreme environment.

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This study uncovered the prevalence, harboured species, and subtype diversity of Cryptosporidium species in river water and its sediment from the Apies River in South Africa. Cryptosporidium spp. concentrations in freshwater and its sediment were determined using Ziehl-Neelsen staining and quantitative Polymerase Chain Reaction (qPCR) techniques. Next-generation sequencing (NGS) targeting the 60 kDa glycoprotein (gp60) gene of Cryptosporidium spp. was performed to reveal the species, subtype families and subtypes harboured in freshwater and its sediment. Although the results revealed that water samples had a higher prevalence (30%) compared with sediment (28%), the number of observable Cryptosporidium spp. oocysts in sediment samples (ranging from 4.90 to 5.81 log10 oocysts per 1 Liter) was higher than that of river water samples (ranging from 4.60 to 5.58 log10 oocysts per 1 L) using Ziehl-Neelsen staining. The 18S ribosomal ribonucleic acid (rRNA) gene copy of Cryptosporidium in riverbed sediments ranged from 6.03 to 7.65 log10, whereas in river water, it was found to be between 4.20 and 6.79 log10. Subtyping results showed that in riverbed sediments, Cryptosporidium parvum accounted for 40.72% of sequences, followed by Cryptosporidium hominis with 23.64%, Cryptosporidium cuniculus with 7.10%, Cryptosporidium meleagridis with 4.44% and the least was Cryptosporidium wrairi with 2.59%. A considerable percentage of reads in riverbed sediment (21.25%) was not assigned to any subtype. River water samples had 45.63% of sequences assigned to C. parvum, followed by 30.32% to C. hominis, 17.99% to C. meleagridis and 5.88% to C. cuniculus. The data obtained are concerning, as Cryptosporidium spp. have intrinsic resistance to water treatment processes and low infectious doses, which can pose a risk to human health due to the various uses of water (for human consumption, leisure, and reuse).  相似文献   
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Cellular and Molecular Neurobiology - Almost a half century of research has elaborated the discoveries of the central mechanisms governing the analgesic responses of opiates, including their...  相似文献   
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