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621.
Dyadic social interactions among 34 adult male golden hamsters reared in either standard wire cages (Experiment 1) or cages with sandy substrates (Experiment 2) were observed for 15 min on consecutive days in two neutral arenas with either a bare Plexiglas or a sandy substrate. The tests showed that in the arena with the sandy substrate the hamsters spent less time engaged in agonistic encounters, initiated fewer agonistic encounters of all kinds and engaged in fewer agonistic encounters of a potentially physically damaging nature (i.e. violent encounters) than they did in the arena with the Plexiglas substrate. These effects were the same in animals reared under either condition. This finding argues against the behavioural effects being due to the novelty of a sand substrate to laboratory-reared hamsters. Consequently, the social behaviour of hamsters in laboratory settings is highly labile across various contexts. Therefore, it is necessary to examine the behavioural effects of contextual variables if general behavioural principles are to be derived from laboratory indices of social behaviour in hamsters, and possibly a number of other species.  相似文献   
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Counselors work in an increasingly complex cultural milieu where every encounter with a client must be considered multicultural in nature. Reflective practice is a central component of professional competence and necessarily involves attention to culture. The cultural auditing model provides an effective and flexible reflective process for enhancing multicultural counseling. The 13 steps in the model are detailed with probes and questions to guide counselor reflection. A case example illuminates the principles involved.  相似文献   
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Discrimination of sensory signals is essential for an organism to form and retrieve memories of relevance in a given behavioral context. Sensory representations are modified dynamically by changes in behavioral state, facilitating context-dependent selection of behavior, through signals carried by noradrenergic input in mammals, or octopamine (OA) in insects. To understand the circuit mechanisms of this signaling, we characterized the function of two OA neurons, sVUM1 neurons, that originate in the subesophageal zone (SEZ) and target the input region of the memory center, the mushroom body (MB) calyx, in larval Drosophila. We found that sVUM1 neurons target multiple neurons, including olfactory projection neurons (PNs), the inhibitory neuron APL, and a pair of extrinsic output neurons, but relatively few mushroom body intrinsic neurons, Kenyon cells. PN terminals carried the OA receptor Oamb, a Drosophila α1-adrenergic receptor ortholog. Using an odor discrimination learning paradigm, we showed that optogenetic activation of OA neurons compromised discrimination of similar odors but not learning ability. Our results suggest that sVUM1 neurons modify odor representations via multiple extrinsic inputs at the sensory input area to the MB olfactory learning circuit.

Behavioral choices depend on discrimination among “sensory objects,” which are neural representations of multiple coincident sensory inputs, across a range of sensory modalities. For example, “odor objects” (Gottfried 2009; Wilson and Sullivan 2011; Gire et al. 2013) are represented in sparse ensembles of neurons, that are coincidence detectors of multiple parallel inputs from odor quality channels. This principle is used widely in animals, including in mushroom bodies (MBs), the insect center for associative memory (Masuda-Nakagawa et al. 2005; Honegger et al. 2011), and in the piriform cortex (PCx) of mammals (Stettler and Axel 2009; Davison and Ehlers 2011).The selectivity of sensory representations can be modulated dynamically by changes in behavioral state, allowing an animal to learn and respond according to perceptual task. In mammals, the noradrenergic system originating in the locus coeruleus (LC) is implicated in signaling behavioral states such as attention, arousal and expectation (Aston-Jones and Cohen 2005; Sara and Bouret 2012).In insects, octopamine (OA), structurally and functionally similar to noradrenalin (NA) in mammals (Roeder 2005), can mediate changes in behavioral state that often promote activity; for example, sensitization of reflex actions in locusts (Sombati and Hoyle 1984), aggressive state in crickets (Stevenson et al. 2005), initiation and maintenance of flight state (Brembs et al. 2007; Suver et al. 2012), and enhanced excitability of Drosophila motion detection neurons during flight (Strother et al. 2018). Another role of OA is as a reward signal: A single OA neuron, VUMmx1, mediates the reinforcing function of unconditioned stimulus in the honeybee proboscis extension reflex (Hammer 1993; Hammer and Menzel 1998; Menzel 2012). In Drosophila, acquisition of appetitive memory is impaired in TβH mutants, unable to synthesize OA (Schwaerzel et al. 2003), and activation of OA neurons can substitute reinforcing stimulus in appetitive learning (Schroll et al. 2006). Moreover, OA receptors are necessary for reward learning in Drosophila (Burke et al. 2012) and crickets (Matsumoto et al. 2015).To understand the neural mechanisms of OA in higher order sensory discrimination, we used the simple sensory “cortex” of larval Drosophila, the calyx, which is the sensory input region of the mushroom bodies (MBs), the insect memory center. Here, each MB neuron (Kenyon cell [KC]) typically arborizes in several glomeruli, most of which are organized around the terminus of an olfactory projection neuron (PN); KCs thus combinatorially integrate multiple sensory input channels (Masuda-Nakagawa et al. 2005) and are coincidence detectors of multiple inputs. The APL provides inhibitory feedback (Lin et al. 2014; Masuda-Nakagawa et al. 2014) and helps to maintain KC sparse responses and odor selectivity (Honegger et al. 2011), analogous to inhibition in the mammalian PCx (Poo and Isaacson 2009; Stettler and Axel 2009; Gire et al. 2013). Thus, odors are represented as a sparse ensemble of KCs that are highly odor selective, a property beneficial for memory (Olshausen and Field 2004).In addition, the larval MB calyx is innervated by two OA neurons, sVUMmd1 and sVUMmx1, ventral unpaired medial neurons with dendritic fields originating in the mandibular and maxillary neuromeres, respectively, of the SEZ in the third instar larva (Selcho et al. 2014). sVUMmd1 and sVUMmx1 are named as OANa-1 and OANa-2, respectively, in the EM connectomic analysis of a 6-h first instar larva (Eichler et al. 2017; Supplemental Fig. 3 of Saumweber et al. 2018). These sVUM1 neurons also innervate the first olfactory neuropile of the antennal lobe (AL). This pattern of innervation is conserved in other insects, for example, the dorsal unpaired median (DUM) neurons in locusts (for review, see Bräunig and Pflüger 2001), the VUMmx1 neuron in honeybees (Hammer 1993; Schröter et al. 2007), and OA-VUMa2 neurons in adult Drosophila (Busch et al. 2009). In adult Drosophila, OA-VUMa2 neurons also show a dense innervation of the lateral horn, implicated in innate behaviors (Busch et al. 2009). The widespread innervation of the insect olfactory neuropiles also resembles the widespread NA innervation of mammalian olfactory processing areas, such as the olfactory bulb, and piriform cortex, by LC neurons originating in the brainstem.We characterized the innervation pattern and synaptic targets of sVUM1 neurons in the calyx, with MB intrinsic and also extrinsic neurons, the localization of the OA receptor Oamb in the calyx circuit, and the impact of sVUM1 neuron activation on behavioral odor discrimination. For this we used an appetitive conditioning paradigm, and tested the ability of larvae to discriminate between similar odors, as opposed to dissimilar odors. Since the larval connectome is based on a single brain, at first instar stage before octopaminergic connections have become as extensive as at third instar, and to obtain a comprehensive understanding of the synaptic targets of sVUM1s in the third-instar larval calyx, we extended our analysis to previously unanalyzed connectivity of VUM1s, to APL and PNs. Further, we combined light microscopy of third-instar larvae with the connectome described by Eichler et al. (2017).We find that sVUM1 neurons in third-instar larvae contact all the major classes of calyx neuron to some degree, consistent with EM synaptic analysis of the 6-h larva (Eichler et al. 2017). A GFP fusion of the OA receptor Oamb is localized in the terminals of PNs, and activating a subset of five SEZ neurons, including sVUM1 neurons, can affect discrimination of similar odors, without affecting underlying olfactory learning and memory ability. We suggest a broad modulatory effect of sVUM1 neurons in the calyx, including a potential role in modulating PN input at the second synapse in the olfactory pathway.  相似文献   
626.
ABSTRACT

A growing number of face-to-face group therapy interventions are being translated into online versions in psycho-oncology. Yet few researchers have systematically described the complex translation process or systematic approaches used to maintain the integrity of the original empirically supported interventions. In this article, we present a case study to illustrate the process of translating an evidence-based face-to-face therapy group, Restoring Body Image after Cancer (ReBIC) into an online format. We highlight how three critical therapeutic components from the original intervention (guided imagery exercises, psychoeducational reading materials, and psychotherapeutic group processes) were maintained and translated for online delivery. We provide preliminary recommendations for future translation efforts of text-based online group therapies to encourage best practices.  相似文献   
627.
Political philosophers have long disagreed on the issue of whether churches should exercise restraint in the appeal to religious reasons in public discussion and political mobilization. Exclusivists defend the restraint, whereas inclusivists reject it. Both sides, however, assume the existence of a democratic government. In this essay, I discuss whether churches should exercise restraint in a non‐democratic, authoritarian society. I defend inclusivism and believe that churches should not restrain themselves, especially when doing so can promote democracy and prevent severe injustices. First, I argue that two exclusivist arguments which justify the restraint cannot be applied in an authoritarian society. Second, I defend inclusivism because religious reasons are effective in cultivating active citizens that strengthen the democratic movement. Finally, I use the Umbrella Movement in Hong Kong as an example to show how inclusivism can enhance democratic movements under authoritarianism.  相似文献   
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Flavour neophobia in gerbils and hamsters was studied by comparing the ingestive/pouching behaviour of these animals when presented with either a familiar unflavoured peanut or a novel one that imparted basic flavours such as sweet, salty, sour, or bitter. Neophobia was expressed by an aversion towards the novel nut manifested by greater latency either to ingest it (gerbils) or to deposit it in the cheek pouch (hamsters) relative to that of the unflavoured one. This method, involving reactions to the taste of novel solid food, provides a more sensitive measure than the traditional one measuring intake of a novel flavoured fluid. The results indicated that gerbils and hamsters encountering either a sweet, salty, or sour nut for the first time showed a neophobic reaction. However, there was no apparent sign of neophobia when the animals were tested with a nut flavoured with quinine. The theoretical implications of these findings are discussed.  相似文献   
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