Roost Site Selection and Site Fidelity in the Neotropical Katydid Docidocercus gigliotosi (Tettigoniidae)

We investigated the remarkable roosting behavior of Docidocercus gigliotosi , an understory pseudophylline katydid in the lowland forests of Panama. The insects used a spiny terrestrial bromeliad, Aechmea magdalenae , as a daytime shelter and were significantly more frequently found in those plants, which had been: (1) higher; (2) of better quality; (3) closer to 'night time walkways' into the canopy; and (4) showed a better central tube condition. The katydids demonstrated strong site fidelity, returning to the same plants for up to 3 wk. Such a choice may provide sufficient protection against some predators and serve as a suitable shelter for the offspring.     

Annual Winter Site Fidelity of Barrow's Goldeneyes in the Pacific

Coastal regions on the Pacific north coast of North America provide important wintering habitat for many species of sea ducks. Although winter range and habitat preferences are well described for most species, fidelity to coastal wintering sites is generally undocumented. Fidelity is an important factor necessary for understanding interactions with coastal developments and activities and corresponding management strategies. We used data from Barrow's goldeneyes (Bucephala islandica), a sea duck that winters predominantly in nearshore habitats along the Pacific north coast, to investigate inter-annual fidelity to, and intra-annual fidelity within, coastal wintering sites. Between 2006 and 2015, we marked goldeneyes on breeding, molting, and wintering sites with satellite transmitters. We retained 4,931 locations in coastal habitats from 221 goldeneyes across 4 coastal regions for our analyses. These birds demonstrated high inter-annual fidelity to coastal wintering sites; 75% of selected wintering sites were within 29 km of sites used the previous winter. Inter-annual fidelity to wintering sites was similar between sex and age classes but differed by coastal region. Goldeneyes from southcentral Alaska, USA, expressed greater inter-annual fidelity relative to birds from northern or southern British Columbia, Canada, and southeast Alaska. Goldeneyes also expressed high intra-annual fidelity within wintering sites, with 75% of individuals averaging within-season movements of ≤9 km. Intra-annual fidelity was lesser for female than male goldeneyes but did not differ between hatch-year and after-hatch-year birds. We found regional variation in intra-annual fidelity, with goldeneyes from southcentral Alaska expressing greater intra-annual fidelity compared to birds from other regions. High inter- and intra-annual winter site fidelity by Barrow's goldeneyes suggests that, at a population level, habitat use is predictable and can be used to inform risk assessment or to evaluate factors affecting habitat choice. Also, low dispersal among wintering sites suggests that recovery from population perturbations, whether caused by natural or anthropogenic events, will be protracted. © 2019 The Wildlife Society.     

PCR-Based Seamless Genome Editing with High Efficiency and Fidelity in Escherichia coli

Efficiency and fidelity are the key obstacles for genome editing toolboxes. In the present study, a PCR-based tandem repeat assisted genome editing (TRAGE) method with high efficiency and fidelity was developed. The design of TRAGE is based on the mechanism of repair of spontaneous double-strand breakage (DSB) via replication fork reactivation. First, cat-sacB cassette flanked by tandem repeat sequence was integrated into target site in chromosome assisted by Red enzymes. Then, for the excision of the cat-sacB cassette, only subculturing is needed. The developed method was successfully applied for seamlessly deleting, substituting and inserting targeted genes using PCR products. The effects of different manipulations including sucrose addition time, subculture times in LB with sucrose and stages of inoculation on the efficiency were investigated. With our recommended procedure, seamless excision of cat-sacB cassette can be realized in 48 h efficiently. We believe that the developed method has great potential for seamless genome editing in E. coli.     

Nest Site Preference and Fidelity of Chinese Alligator(Alligator sinensis)

Oviparous female reptiles select nesting sites with optimal ecological factors that contribute to egg development. Chinese alligator(Alligator sinensis), an oviparous reptile, is a critically endangered crocodilian with temperature-dependent sex determination. Research on its nesting behavior may facilitate the protection of this species. In this study, we monitored nesting behavior over eight years. We compared selected frequency of nest sites, distance from nest site to water, height from nest site top to the water surface, distance from nest site to human activity region, and canopy density between nest sites on the island and bank. The results showed that 45 nest sites were used by female alligators over eight years and each site was selected from one to 10 times. The selected frequency of nest site occurrence on the island was higher than that on the bank(P 0.001). We observed that 88% of the individual alligators(15/17) showed different degrees of nest site fidelity. However, Chinese alligators might not always be loyal to only one nest site because of environmental changes or interspecific competition at nest sites. Our findings suggest that female alligators prefer to nest at island, which might be because of the nests on the island had a higher canopy density(P = 0.010) and were further from the human activity region(P 0.001) than those on the bank did. It would be beneficial to reduce human activities during the breeding season and protect the vegetation of Chinese alligator habitats in the future. of the beach(Ali et al., 2005; Kamel and Mrosovsky, 2005; Turkozan et al., 2012). Other species such as snakes and lizards select nest sites with more moist substrates, which significantly increases their body size at hatching(Brown and Shine, 2004; Reedy et al., 2013). Nest site preference may be maintained for one or more breeding seasons(Janzen and Morjan, 2001; Kamel et al., 2006). When female chose the same site or area during different years, it is called nest site fidelity(Switzer, 1993). This nest choice behavior may influence offspring survival(Lindeman, 1992) and nest site fidelity has been documented in numerous species such as birds(Lindberg and Sedinger, 1997), turtles(Mitrus, 2006; Walde et al., 2007), tuatara(Refsnider et al., 2010), and crocodilians(Elsey et al., 2008).Chinese alligator(Alligator sinensis) is a critically endangered freshwater crocodilian endemic to China(Thorbjarnarson and Wang, 1999). Recent investigations show that there are no more than 130 Chinese alligators     

Long-Term Changes in Species Composition and Relative Abundances of Sharks at a Provisioning Site

Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today’s recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004–2006 and 2007–2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004–2006 and very rare in the period of 2007–2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark species.     

Some Mechanisms of Disturbances and Recovery of T-Lymphocyte Migratory Properties In Irradiated Mice

Abstract Migration of ⁵¹Cr-labelled T cells from irradiated mice into lymph nodes of syngeneic unirradiated recipients decreased in a dose-dependent fashion. Influx of labelled T cells between 4 and 24 hr after injection (secondary migration) is more radiosensitive than lymph-node migration of T cells in the first 4 hr (primary migration). Treatment of T cells from irradiated mice in vitro with Con A or with trypsin does not enhance radiation-induced alteration of their migratory properties, but irradiation enhances the effects of Con A and trypsin on T-cell migration. Recovery of primary migration of irradiated T cells is completed 3 months after irradiation; it is probably caused by T-cell renewal. the defect of T-cell secondary migration is more stable: it remains 6 months after irradiation in a dose of 4 Gy. Post-irradiation defects of the T-cell differentiation process as a cause of long-lasting alteration of T-cell secondary migration are discussed.     

Long-Term Asymmetric Hearing Affects Cochlear Implantation Outcomes Differently in Adults with Pre- and Postlingual Hearing Loss

In many countries, a single cochlear implant is offered as a treatment for a bilateral hearing loss. In cases where there is asymmetry in the amount of sound deprivation between the ears, there is a dilemma in choosing which ear should be implanted. In many clinics, the choice of ear has been guided by an assumption that the reorganisation of the auditory pathways caused by longer duration of deafness in one ear is associated with poorer implantation outcomes for that ear. This assumption, however, is mainly derived from studies of early childhood deafness. This study compared outcomes following implantation of the better or poorer ear in cases of long-term hearing asymmetries. Audiological records of 146 adults with bilateral hearing loss using a single hearing aid were reviewed. The unaided ear had 15 to 72 years of unaided severe to profound hearing loss before unilateral cochlear implantation. 98 received the implant in their long-term sound-deprived ear. A multiple regression analysis was conducted to assess the relative contribution of potential predictors to speech recognition performance after implantation. Duration of bilateral significant hearing loss and the presence of a prelingual hearing loss explained the majority of variance in speech recognition performance following cochlear implantation. For participants with postlingual hearing loss, similar outcomes were obtained by implanting either ear. With prelingual hearing loss, poorer outcomes were obtained when implanting the long-term sound-deprived ear, but the duration of the sound deprivation in the implanted ear did not reliably predict outcomes. Contrary to an apparent clinical consensus, duration of sound deprivation in one ear has limited value in predicting speech recognition outcomes of cochlear implantation in that ear. Outcomes of cochlear implantation are more closely related to the period of time for which the brain is deprived of auditory stimulation from both ears.     

Reconstructing the Migratory Behavior and Long-Term Survivorship of Juvenile Chinook Salmon under Contrasting Hydrologic Regimes

The loss of genetic and life history diversity has been documented across many taxonomic groups, and is considered a leading cause of increased extinction risk. Juvenile salmon leave their natal rivers at different sizes, ages and times of the year, and it is thought that this life history variation contributes to their population sustainability, and is thus central to many recovery efforts. However, in order to preserve and restore diversity in life history traits, it is necessary to first understand how environmental factors affect their expression and success. We used otolith ⁸⁷Sr/⁸⁶Sr in adult Chinook salmon (Oncorhynchus tshawytcha) returning to the Stanislaus River in the California Central Valley (USA) to reconstruct the sizes at which they outmigrated as juveniles in a wetter (2000) and drier (2003) year. We compared rotary screw trap-derived estimates of outmigrant timing, abundance and size with those reconstructed in the adults from the same cohort. This allowed us to estimate the relative survival and contribution of migratory phenotypes (fry, parr, smolts) to the adult spawning population under different flow regimes. Juvenile abundance and outmigration behavior varied with hydroclimatic regime, while downstream survival appeared to be driven by size- and time-selective mortality. Although fry survival is generally assumed to be negligible in this system, >20% of the adult spawners from outmigration year 2000 had outmigrated as fry. In both years, all three phenotypes contributed to the spawning population, however their relative proportions differed, reflecting greater fry contributions in the wetter year (23% vs. 10%) and greater smolt contributions in the drier year (13% vs. 44%). These data demonstrate that the expression and success of migratory phenotypes vary with hydrologic regime, emphasizing the importance of maintaining diversity in a changing climate.     

Movements,Home Range and Site Fidelity of Snapper (Chrysophrys auratus) within a Temperate Marine Protected Area

Understanding the movement dynamics of marine fish provides valuable information that can assist with species management, particularly regarding protection within marine protected areas (MPAs). We performed an acoustic tagging study implemented within the Port Stephens-Great Lakes Marine Park on the mid-north coast of New South Wales, Australia, to assess the movement patterns, home range and diel activity of snapper (Chrysophrys auratus; Sparidae); a species of significant recreational and commercial fishing importance in Australia. The study focused on C. auratus movements around Cabbage Tree Island, which is predominantly a no-take sanctuary zone (no fishing), with an array of acoustic stations deployed around the island and adjacent reefs and islands. Thirty C. auratus were tagged with internal acoustic tags in November 2010 with their movements recorded until September 2014. Both adult and juvenile C. auratus were observed to display strong site fidelity to Cabbage Tree Island with a mean 12-month residency index of 0.83 (range = 0 low to 1 high). Only three fish were detected on acoustic receivers away from Cabbage Tree Island, with one fish moving a considerable distance of ~ 290 kms over a short time frame (46 days). The longest period of residency recorded at the island was for three fish occurring regularly at the site for a period of 1249 days. Chrysophrys auratus displayed strong diurnal behaviour and detection frequency was significantly higher during the day than at night; however, there was no significant difference in detection frequency between different hours. This study demonstrates that even small-scale protected areas can benefit C. auratus during multiple life-history stages as it maintains a small home range and displays strong site fidelity over a period of 3 years.     

The Flight Apparatus of Migratory and Sedentary Individuals of a Partially Migratory Songbird Species

Variations in the geometry of the external flight apparatus of birds are beneficial for different behaviors. Long-distance flight is less costly with more pointed wings and shorter tails; however these traits decrease maneuverability at low speeds. Selection has led to interspecific differences in these and other flight apparatuses in relation to migration distance. If these principles are general, how are the external flight apparatus within a partially migratory bird species shaped in which individuals either migrate or stay at their breeding grounds? We resolved this question by comparing the wing pointedness and tail length (relative to wing length) of migrant and resident European blackbirds (Turdus merula) breeding in the same population. We predicted that migrant blackbirds would have more pointed wings and shorter tails than residents. Contrary to our predictions, there were no differences between migrants and residents in either measure. Our results indicate that morphological differences between migrants and residents in this partially migratory population may be constrained.     

Return Customers: Foraging Site Fidelity and the Effect of Environmental Variability in Wide-Ranging Antarctic Fur Seals

Strategies employed by wide-ranging foraging animals involve consideration of habitat quality and predictability and should maximise net energy gain. Fidelity to foraging sites is common in areas of high resource availability or where predictable changes in resource availability occur. However, if resource availability is heterogeneous or unpredictable, as it often is in marine environments, then habitat familiarity may also present ecological benefits to individuals. We examined the winter foraging distribution of female Antarctic fur seals, Arctocephalus gazelle, over four years to assess the degree of foraging site fidelity at two scales; within and between years. On average, between-year fidelity was strong, with most individuals utilising more than half of their annual foraging home range over multiple years. However, fidelity was a bimodal strategy among individuals, with five out of eight animals recording between-year overlap values of greater than 50%, while three animals recorded values of less than 5%. High long-term variance in sea surface temperature, a potential proxy for elevated long-term productivity and prey availability, typified areas of overlap. Within-year foraging site fidelity was weak, indicating that successive trips over the winter target different geographic areas. We suggest that over a season, changes in prey availability are predictable enough for individuals to shift foraging area in response, with limited associated energetic costs. Conversely, over multiple years, the availability of prey resources is less spatially and temporally predictable, increasing the potential costs of shifting foraging area and favouring long-term site fidelity. In a dynamic and patchy environment, multi-year foraging site fidelity may confer a long-term energetic advantage to the individual. Such behaviours that operate at the individual level have evolutionary and ecological implications and are potential drivers of niche specialization and modifiers of intra-specific competition.     

Biological Observations of Monarch Butterfly Behavior at a Migratory Stopover Site: Results from a Long-term Tagging Study in Coastal South Carolina

Like most migratory species, monarch butterflies (Danaus plexippus) must stop frequently during their long southward migration to rest and refuel, and the places where they stop are important for the success of the migration. The behavior of monarch butterflies at migratory stopover sites has never been examined in detail. Here we present results of a long-term study of monarchs at one stopover site in coastal South Carolina where over 12,000 monarchs have been captured, measured and tagged (with numbered stickers to track recovery rates) over 13 years. Only 3 monarchs (0.023%) were recovered at the monarchs’ overwintering sites in Mexico, which is consistent with other tagging studies on the eastern coast. The migration season was longer at this site than at inland locations and monarchs continued to be captured in November and December, when most monarchs had already arrived at the overwintering areas in Mexico. In addition, there were 94 monarchs captured between Jan 1 and Mar 15, indicating that some monarchs overwinter at this site. Of all monarchs captured during the migration season, 80% were captured while nectaring and 10% while roosting. Others were basking, resting, flying and even mating. The sex ratio was male biased by three to one in all behavior categories except those captured mating. Roosting and nectaring monarchs had fresher wings than those in other behavior categories, suggesting that these are younger individuals. There were 13 observations of females ovipositing on non-native Asclepias curassavica during the fall months, which speaks to the potential for this plant to pull monarchs out of the migratory pool. Aside from these insights, this study also serves as an example of the potential that monarch tagging studies have to advance scientific understanding of monarch migration.     

Fidelity of Target Site Duplication and Sequence Preference during Integration of Xenotropic Murine Leukemia Virus-Related Virus

Xenotropic murine leukemia virus (MLV)-related virus (XMRV) is a new human retrovirus associated with prostate cancer and chronic fatigue syndrome. The causal relationship of XMRV infection to human disease and the mechanism of pathogenicity have not been established. During retrovirus replication, integration of the cDNA copy of the viral RNA genome into the host cell chromosome is an essential step and involves coordinated joining of the two ends of the linear viral DNA into staggered sites on target DNA. Correct integration produces proviruses that are flanked by a short direct repeat, which varies from 4 to 6 bp among the retroviruses but is invariant for each particular retrovirus. Uncoordinated joining of the two viral DNA ends into target DNA can cause insertions, deletions, or other genomic alterations at the integration site. To determine the fidelity of XMRV integration, cells infected with XMRV were clonally expanded and DNA sequences at the viral-host DNA junctions were determined and analyzed. We found that a majority of the provirus ends were correctly processed and flanked by a 4-bp direct repeat of host DNA. A weak consensus sequence was also detected at the XMRV integration sites. We conclude that integration of XMRV DNA involves a coordinated joining of two viral DNA ends that are spaced 4 bp apart on the target DNA and proceeds with high fidelity.     

Expression of CD11c Is Associated with Unconventional Activated T Cell Subsets with High Migratory Potential

CD11c is an α integrin classically employed to define myeloid dendritic cells. Although there is little information about CD11c expression on human T cells, mouse models have shown an association of CD11c expression with functionally relevant T cell subsets. In the context of genital tract infection, we have previously observed increased expression of CD11c in circulating T cells from mice and women. Microarray analyses of activated effector T cells expressing CD11c derived from naïve mice demonstrated enrichment for natural killer (NK) associated genes. Here we find that murine CD11c⁺ T cells analyzed by flow cytometry display markers associated with non-conventional T cell subsets, including γδ T cells and invariant natural killer T (iNKT) cells. However, in women, only γδ T cells and CD8⁺ T cells were enriched within the CD11c fraction of blood and cervical tissue. These CD11c⁺ cells were highly activated and had greater interferon (IFN)-γ secretory capacity than CD11c^- T cells. Furthermore, circulating CD11c⁺ T cells were associated with the expression of multiple adhesion molecules in women, suggesting that these cells have high tissue homing potential. These data suggest that CD11c expression distinguishes a population of circulating T cells during bacterial infection with innate capacity and mucosal homing potential.     

Ribavirin-Resistant Mutants of Human Enterovirus 71 Express a High Replication Fidelity Phenotype during Growth in Cell Culture

It has been shown in animal models that ribavirin-resistant poliovirus with a G64S mutation in its 3D polymerase has high replication fidelity coupled with attenuated virulence. Here, we describe the effects of mutagenesis in the human enterovirus 71 (HEV71) 3D polymerase on ribavirin resistance and replication fidelity. Seven substitutions were introduced at amino acid position 3D-G64 of a HEV71 full-length infectious cDNA clone (26M). Viable clone-derived virus populations were rescued from the G64N, G64R, and G64T mutant cDNA clones. The clone-derived G64R and G64T mutant virus populations were resistant to growth inhibition in the presence of 1,600 μM ribavirin, whereas the growth of parental 26M and the G64N mutant viruses were inhibited in the presence of 800 μM ribavirin. Nucleotide sequencing of the 2C and 3D coding regions revealed that the rate of random mutagenesis after 13 passages in the presence of 400 μM ribavirin was nearly 10 times higher in the 26M genome than in the mutant G64R virus genome. Furthermore, random mutations acquired in the 2C coding regions of 26M and G64N conferred resistance to growth inhibition in the presence of 0.5 mM guanidine, whereas the G64R and G64T mutant virus populations remained susceptible to growth inhibition by 0.5 mM guanidine. Interestingly, a S264L mutation identified in the 3D coding region of 26M after ribavirin selection was also associated with both ribavirin-resistant and high replication fidelity phenotypes. These findings are consistent with the hypothesis that the 3D-G64R, 3D-G64T, and 3D-S264L mutations confer resistance upon HEV71 to the antiviral mutagen ribavirin, coupled with a high replication fidelity phenotype during growth in cell culture.     

Identification and Characterization of a New Serotonergic Recognition Site with High Affinity for 5-Carboxamidotryptamine in Mammalian Brain

Abstract: We analyzed the existence of an additional serotonin (5-HT) receptor subtype, sensitive to 5-carboxamidotryptamine, in the mammalian brain. Radioligand binding studies with [³H]5-HT were carried out in rat, guinea pig, and human brain membranes, in the presence of unlabeled drugs to mask the binding to all known 5-HT receptors, with the exception of 5-HT_1E sites. Under these conditions, unlabeled 5-carboxamidotryptamine still showed a biphasic competition curve with a nanomolar affinity component. Saturation studies with 5-[³H]carboxamidotryptamine were carried out in the presence of (±)-8-hydroxy-2-(di- n -propylamino)tetralin, mesulergine, and ergotamine, to mask the binding to all receptors known to be labeled by 5-carboxamidotryptamine. These studies showed the existence in cortex and hippocampus from guinea pig and human brain of a remaining binding site with high affinity ( pK _D = 7.8–8.1) and a unique pharmacological profile. 5-HT and 5-carboxamidotryptamine showed nanomolar affinity, whereas 5-methoxytryptamine recognized this binding site with intermediate affinity. Other drugs exhibited low or very low potency in inhibiting this binding. The addition of 5'-guanylylimidodiphosphate significantly reduced the number of binding sites labeled by 5-[³H]carboxamidotryptamine, in the presence of the masking drugs described above, indicating the interaction with a GTP-binding protein. Preliminary autoradiographic studies in human brain appear to indicate that this 5-HT binding site is present in areas such as the globus pallidus, neocortex, and hippocampus, among others.     

超声乳化人工晶状体植入术治疗高度近视合并白内障的效果

目的:探讨超声乳化人工晶状体植入术在高度近视合并白内障中的应用及对中央角膜厚度(CCT)、角膜内皮细胞计数(CEC)、图像视觉诱发电位(P-VEP)与黄斑光学相干断层成象(OCT)的影响。方法:选择2014年1月至2016年6月我院接诊的96例高度近视合并白内障患者,通过随机数表法分为观察组(n=48)和对照组(n=48)。对照组行白内障囊外摘出人工晶状体植入术,观察组行超声乳化人工晶状体植入术。手术1个月后,比较两组CCT、CEC、P-VEP、黄斑OCT、最佳矫正视力以及并发症的发生情况。结果:手术后,观察组CCT、CEC均明显高于对照组(P0.05)。P-VEP检测结果显示观察组P100波振幅明显高于对照组,P100波潜时显著低于对照组(P0.05)。黄斑OCT结果显示观察组黄斑中心凹厚度明显低于对照组(P0.05);观察组最佳矫正视力明显高于对照组(P0.05);观察组并发症的总发生率明显低于对照组(P0.05)。结论:应用超声乳化人工晶状体植入术治疗高度近视合并白内障患者的效果显著,可有效减轻对角膜内皮的损伤,促进视力恢复,提高视觉质量。