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141.
Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian).  相似文献   
142.
Infectious and inflammatory diseases in the intestine remain a serious threat for patients world-wide. Reprogramming of the intestinal epithelium towards a protective effector state is important to manage inflammation and immunity and can be therapeutically targeted. The role of epigenetic regulatory enzymes within these processes is not yet defined. Here, we use a mouse model that has an intestinal-epithelial specific deletion of the histone demethylase Lsd1 (cKO mice), which maintains the epithelium in a fixed reparative state. Challenge of cKO mice with bacteria-induced colitis or a helminth infection model both resulted in increased pathogenesis. Mechanistically, we discovered that LSD1 is important for goblet cell maturation and goblet-cell effector molecules such as RELMß. We propose that this may be in part mediated by directly controlling genes that facilitate cytoskeletal organization, which is important in goblet cell biology. This study therefore identifies intestinal-epithelial epigenetic regulation by LSD1 as a critical element in host protection from infection.  相似文献   
143.
Pocillopora damicornis (Linnaeus, 1758; Scleractinia, Pocilloporidae) has recently been found to comprise at least five distinct genetic lineages in Eastern Australia, some of which likely represent cryptic species. Due to similar and plastic gross morphology of these lineages, field identification is often difficult. Here we present a quick, cost effective genetic assay as well as three novel microsatellite markers that distinguish the two most common lineages found on the Great Barrier Reef. The assay is based on PCR amplification of two regions within the mitochondrial putative control region, which show consistent and easily identifiable fragment size differences for the two genetic lineages after Alu1 restriction enzyme digestion of the amplicons.  相似文献   
144.
Adapted tango dancing improves mobility and balance in older adults and additional populations with balance impairments. It is composed of very simple step elements. Adapted tango involves movement initiation and cessation, multi-directional perturbations, varied speeds and rhythms. Focus on foot placement, whole body coordination, and attention to partner, path of movement, and aesthetics likely underlie adapted tango’s demonstrated efficacy for improving mobility and balance. In this paper, we describe the methodology to disseminate the adapted tango teaching methods to dance instructor trainees and to implement the adapted tango by the trainees in the community for older adults and individuals with Parkinson’s Disease (PD). Efficacy in improving mobility (measured with the Timed Up and Go, Tandem stance, Berg Balance Scale, Gait Speed and 30 sec chair stand), safety and fidelity of the program is maximized through targeted instructor and volunteer training and a structured detailed syllabus outlining class practices and progression.  相似文献   
145.
The effects of temperature and light on the breakdown of the coral-Symbiodinium symbiosis are well documented but current understanding of their roles during initial uptake and establishment of symbiosis is limited. In this study, we investigate how temperature and light affect the uptake of the algal symbionts, ITS1 types C1 and D, by juveniles of the broadcast-spawning corals Acropora tenuis and A. millepora. Elevated temperatures had a strong negative effect on Symbiodinium uptake in both coral species, with corals at 31°C showing as little as 8% uptake compared to 87% at 28°C. Juveniles in high light treatments (390 µmol photons m−2 s−1) had lower cell counts across all temperatures, emphasizing the importance of the light environment during the initial uptake phase. The proportions of the two Symbiodinium types taken up, as quantified by a real time PCR assay using clade C- and D-specific primers, were also influenced by temperature, although variation in uptake dynamics between the two coral species indicates a host effect. At 28°C, A. tenuis juveniles were dominated by C1 Symbiodinium, and while the number of D Symbiodinium cells increased at 31°C, they never exceeded the number of C1 cells. In contrast, juveniles of A. millepora had approximately equal numbers of C1 and D cells at 28°C, but were dominated by D at 30°C and 31°C. This study highlights the significant role that environmental factors play in the establishment of coral-Symbiodinium symbiosis and provides insights into how potentially competing Symbiodinium types take up residence in coral juveniles.  相似文献   
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147.
In intact eels in sea water (SW), ovine prolactin (PRL) treatment induces hypercalcemia, but its mechanism of action, which is discussed, remains to be defined. Corpuscles of Stannius (CSt) are modified simultaneously: two cell categories then become evident. The first cell type (type 1) predominates; it has an oval shape and large granules, it shows a nuclear and nucleolar hypertrophy and a mitotic activity, and appears greatly stimulated by PRL; it may elaborate a hypocalcemic factor (hypocalcin) which would compensate for the PRL-induced hypercalcemia. A similar effect, although slightly less intense, is detected in hypophysectomized-PRL treated eels in SW. A second cell type (type 2), is more elongated, smaller in size, and has an oval nucleus and fine granules. Scarcely less active in SW, it is significantly stimulated by PRL despite an increased blood sodium and potassium level. This experiment does not help to clarify its function.  相似文献   
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The short 8–10 amino acid “hinge” sequence in lactose repressor (LacI), present in other LacI/GalR family members, links DNA and inducer‐binding domains. Structural studies of full‐length or truncated LacI‐operator DNA complexes demonstrate insertion of the dimeric helical “hinge” structure at the center of the operator sequence. This association bends the DNA ~40° and aligns flanking semi‐symmetric DNA sites for optimal contact by the N‐terminal helix‐turn‐helix (HtH) sequences within each dimer. In contrast, the hinge region remains unfolded when bound to nonspecific DNA sequences. To determine ability of the hinge helix alone to mediate DNA binding, we examined (i) binding of LacI variants with deletion of residues 1–50 to remove the HtH DNA binding domain or residues 1–58 to remove both HtH and hinge domains and (ii) binding of a synthetic peptide corresponding to the hinge sequence with a Val52Cys substitution that allows reversible dimer formation via a disulfide linkage. Binding affinity for DNA is orders of magnitude lower in the absence of the helix‐turn‐helix domain with its highly positive charge. LacI missing residues 1–50 binds to DNA with ~4‐fold greater affinity for operator than for nonspecific sequences with minimal impact of inducer presence; in contrast, LacI missing residues 1–58 exhibits no detectable affinity for DNA. In oxidized form, the dimeric hinge peptide alone binds to O1 and nonspecific DNA with similarly small difference in affinity; reduction to monomer diminished binding to both O1 and nonspecific targets. These results comport with recent reports regarding LacI hinge interaction with DNA sequences.  相似文献   
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