224 research outputs found
Macroalgae contribute to the diet of Patella vulgata from contrasting conditions of latitude and wave exposure in the UK
Analysis of gut contents and stable isotope composition of intertidal limpets (Patella vulgata) showed a major contribution of macroalgae to their diet, along with microalgae and invertebrates. Specimens were collected in areas with limited access to attached macroalgae, suggesting a major dietary component of drift algae. Gut contents of 480 animals from 2 moderately wave exposed and 2 sheltered rocky shores in each of 2 regions: western Scotland (55–56°N) and southwest England (50°N), were analysed in 2 years (n = 30 per site per year). The abundance of microalgae, macroalgae and invertebrates within the guts was quantified using categorical abundance scales. Gut content composition was compared among regions and wave exposure conditions, showing that the diet of P. vulgata changes with both wave exposure and latitude. Microalgae were most abundant in limpet gut contents in animals from southwest sites, whilst leathery/corticated macroalgae were more prevalent and abundant in limpets from sheltered and northern sites. P. vulgata appears to have a more flexible diet than previously appreciated and these keystone grazers consume not only microalgae, but also large quantities of macroalgae and small invertebrates. To date, limpet grazing studies have focussed on their role in controlling recruitment of macroalgae by feeding on microscopic propagules and germlings. Consumption of adult algae suggests P. vulgata may also directly control the biomass of attached macroalgae on the shore, whilst consumption of drift algae indicates the species may play important roles in coupling subtidal and intertidal production
Complete structure of an epithelial keratin dimer: implications for intermediate filament assembly
Keratins are cytoskeletal proteins that hierarchically arrange into filaments, starting with the dimer sub-unit. They are integral to the structural support of cells, in skin, hair and nails. In skin, keratin is thought to play a critical role in conferring the barrier properties and elasticity of skin. In general, the keratin dimer is broadly described by a tri-domain structure: a head, a central rod and a tail. As yet, no atomistic-scale picture of the entire dimer structure exists; this information is pivotal for establishing molecular-level connections between structure and function in intermediate filament proteins. The roles of the head and tail domains in facilitating keratin filament assembly and function remain as open questions. To address these, we report results of molecular dynamics simulations of the entire epithelial human K1/K10 keratin dimer. Our findings comprise: (1) the first three-dimensional structural models of the complete dimer unit, comprising of the head, rod and tail domains; (2) new insights into the chirality of the rod-domain twist gained from analysis of the full domain structure; (3) evidence for tri-subdomain partitioning in the head and tail domains; and, (4) identification of the residue characteristics that mediate non-covalent contact between the chains in the dimer. Our findings are immediately applicable to other epithelial keratins, such as K8/K18 and K5/K14, and to intermediate filament proteins in general
Traditions in Spider Monkeys Are Biased towards the Social Domain
Cross-site comparison studies of behavioral variation can provide evidence for traditions in wild species once ecological and genetic factors are excluded as causes for cross-site differences. These studies ensure behavior variants are considered within the context of a species' ecology and evolutionary adaptations. We examined wide-scale geographic variation in the behavior of spider monkeys (Ateles geoffroyi) across five long-term field sites in Central America using a well established ethnographic cross-site survey method. Spider monkeys possess a relatively rare social system with a high degree of fission-fusion dynamics, also typical of chimpanzees (Pan troglodytes) and humans (Homo sapiens). From the initial 62 behaviors surveyed 65% failed to meet the necessary criteria for traditions. The remaining 22 behaviors showed cross-site variation in occurrence ranging from absent through to customary, representing to our knowledge, the first documented cases of traditions in this taxon and only the second case of multiple traditions in a New World monkey species. Of the 22 behavioral variants recorded across all sites, on average 57% occurred in the social domain, 19% in food-related domains and 24% in other domains. This social bias contrasts with the food-related bias reported in great ape cross-site comparison studies and has implications for the evolution of human culture. No pattern of geographical radiation was found in relation to distance across sites. Our findings promote A. geoffroyi as a model species to investigate traditions with field and captive based experiments and emphasize the importance of the social domain for the study of animal traditions.Research at Barro Colorado Island was supported by grants from the National Science Foundation (SBR-9711161), the Leakey Foundation, the Department of Anthropology, University of California, Berkeley (www.berkeley.edu) and a Short-term Fellowship from the Smithsonian Tropical Research Institute (www.stri.org). Research at Corcovado National Park's Sirena Biological Station was supported by NSF award 0233248 (with R. Sussman), the Wenner-Gren Foundation, the Leakey Foundation, the American Society of Primatologists (www.asp.org), and Washington University in St. Louis (www.wustl.edu). Funds for Sirena's field lab facility were provided to L. E. Gilbert (Univ. of Texas at Austin) by NSF BSR 8315399 and a matching WWF grant, and funds for updating Sirena's trail system and installation of spatial reference system were provided by the Mellon Foundation through the Institute of Latin American Studies at UT Austin. Research at Santa Rosa and Punta Laguna was supported by The British Academy (www.britac.ac.uk), the Wenner-Gren Foundation (www.wennergren.org), the Leakey Foundation (www.leakeyfoundation.org) and the North of England Zoological Society (www.chesterzoo.org). CJS was supported by a Gladstone bursary from the University of Chester (www.chester.ac.uk) and by the Santander University Scheme (www.santander.co.uk). Research at Runaway Creek was supported by the Natural Sciences and Engineering Research Council of Canada
Traditions in spider monkeys are biased towards the social domain
Cross-site comparison studies of behavioral variation can provide evidence for traditions in wild species once ecological and genetic factors are excluded as causes for cross-site differences. These studies ensure behavior variants are considered within the context of a species' ecology and evolutionary adaptations. We examined wide-scale geographic variation in the behavior of spider monkeys (Ateles geoffroyi) across five long-term field sites in Central America using a well established ethnographic cross-site survey method. Spider monkeys possess a relatively rare social system with a high degree of fission-fusion dynamics, also typical of chimpanzees (Pan troglodytes) and humans (Homo sapiens). From the initial 62 behaviors surveyed 65% failed to meet the necessary criteria for traditions. The remaining 22 behaviors showed cross-site variation in occurrence ranging from absent through to customary, representing to our knowledge, the first documented cases of traditions in this taxon and only the second case of multiple traditions in a New World monkey species. Of the 22 behavioral variants recorded across all sites, on average 57% occurred in the social domain, 19% in food-related domains and 24% in other domains. This social bias contrasts with the food-related bias reported in great ape cross-site comparison studies and has implications for the evolution of human culture. No pattern of geographical radiation was found in relation to distance across sites. Our findings promote A. geoffroyi as a model species to investigate traditions with field and captive based experiments and emphasize the importance of the social domain for the study of animal traditions.Research at Barro Colorado Island was supported by grants from the National Science Foundation (SBR-9711161), the Leakey Foundation, the Department of Anthropology, University of California, Berkeley (www.berkeley.edu) and a Short-term Fellowship from the Smithsonian Tropical Research Institute (www.stri.org). Research at Corcovado National Park's Sirena Biological Station was supported by NSF award 0233248 (with R. Sussman), the Wenner-Gren Foundation, the Leakey Foundation, the American Society of Primatologists (www.asp.org), and Washington University in St. Louis (www.wustl.edu). Funds for Sirena's field lab facility were provided to L. E. Gilbert (Univ. of Texas at Austin) by NSF BSR 8315399 and a matching WWF grant, and funds for updating Sirena's trail system and installation of spatial reference system were provided by the Mellon Foundation through the Institute of Latin American Studies at UT Austin. Research at Santa Rosa and Punta Laguna was supported by The British Academy (www.britac.ac.uk), the Wenner-Gren Foundation (www.wennergren.org), the Leakey Foundation (www.leakeyfoundation.org) and the North of England Zoological Society (www.chesterzoo.org). CJS was supported by a Gladstone bursary from the University of Chester (www.chester.ac.uk) and by the Santander University Scheme (www.santander.co.uk). Research at Runaway Creek was supported by the Natural Sciences and Engineering Research Council of Canada. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
An Analysis of Efficiency Improvements in Residential Sized Heat Pumps
The objectives of this study included: (1) development of
classes of heat pumps, (2) evaluation and selection of a suitable
heat pump design model, (3) characterization of suitable baseline
heat pump designs, (4) selection of design options that can be
used to improve heat pump efficiency, and (5) development of
heat pump designs to cover the whole spectrum of efficiencies
available today and those that may be technologically feasible in
the next few years
Building Energy Use and Conservation in Cycle VIII of the Texas Institutional Conservation Program
Sixty-two technical assistance (energy audit)
reports by twelve different consulting firms representing
fifteen independent school districts, nine
hospitals, and five colleges have been reviewed to
assess energy use characteristics and recommended
energy saving measures. Such measures include both
maintenance and operation (H&O) measures (generally
regarded as "low-cost, no-cost") and energy conservation
(ECH) measures (generally more expensive and
requiring outside skills). Implementation cost,
annual savings of energy and costs, and paybacks
were reported for all M&Os and ECHs. Measures were
broken down by the consulting firms according to
energy use characteristics and categories, and it
was determined that average costs for electricity
and gas, before implementation of M&Os and ECHs,
were 4.85/MMBTU respectively. The
total implementation cost and projected annual
savings for the M&Os are 223,000
respectively, yielding a four-month payback. The
corresponding results for implementation of ECHs are
555,000, resulting in a four-year
payback. Also, some obvious problems in the preparation
of technical assistance reports along with
the general background and implementation of the
Institutional Conservation Program in Texas,
resulting from the National Energy Act of 1978, are
discussed
Synthesis and functionalization of azetidine‐containing small macrocyclic peptides
Cyclic peptides are increasingly important structures in drugs but their development can be impeded by difficulties associated with their synthesis. Here, we introduce the 3-aminoazetidine (3-AAz) subunit as a new turn-inducing element for the efficient synthesis of small head-to-tail cyclic peptides. Greatly improved cyclizations of tetra-, penta- and hexapeptides (28 examples) under standard reaction conditions are achieved by introduction of this element within the linear peptide precursor. Post-cyclization deprotection of the amino acid side chains with strong acid is realized without degradation of the strained four-membered azetidine. An special feature of this chemistry is that further late-stage modification of the resultant macrocyclic peptides can be achieved via the 3-AAz unit. This is done by: (i) chemoselective deprotection and substitution at the azetidine nitrogen, or by (ii) a click-based approach employing a 2-propynyl carbamate on the azetidine nitrogen. In this way, a range of dye and biotin tagged macrocycles are readily produced. Structural insights gained by XRD analysis of a cyclic tetrapeptide indicate that the azetidine ring encourages access to the less stable, all-trans conformation. Moreover, introduction of a 3-AAz into a representative cyclohexapeptide improves stability towards proteases compared to the homodetic macrocycle
The Care Home Independent Prescribing Pharmacist Study (CHIPPS)—a non- randomised feasibility study of independent pharmacist prescribing in care homes
Background
Residents in care homes are often very frail, have complex medicine regimens and are at high risk of adverse drug events. It has been recommended that one healthcare professional should assume responsibility for their medicines management. We propose that this could be a pharmacist independent prescriber (PIP). This feasibility study aimed to test and refine the service specification and proposed study processes to inform the design and outcome measures of a definitive randomised controlled trial to examine the clinical and cost effectiveness of PIPs working in care homes compared to usual care. Specific objectives included testing processes for participant identification, recruitment and consent and assessing retention rates; determining suitability of outcome measures and data collection processes from care homes and GP practices to inform selection of a primary outcome measure; assessing service and research acceptability; and testing and refining the service specification.
Methods
Mixed methods (routine data, questionnaires and focus groups/interviews) were used in this non-randomised open feasibility study of a 3-month PIP intervention in care homes for older people. Data were collected at baseline and 3 months. One PIP, trained in service delivery, one GP practice and up to three care homes were recruited at each of four UK locations. For ten eligible residents (≥ 65 years, on at least one regular medication) in each home, the PIP undertook management of medicines, repeat prescription authorisation, referral to other healthcare professionals and staff training. Outcomes (falls, medications, resident’s quality of life and activities of daily living, mental state and adverse events) were described at baseline and follow-up and assessed for inclusion in the main study. Participants’ views post-intervention were captured in audio-recorded focus groups and semi-structured interviews. Transcripts were thematically analysed.
Results
Across the four locations, 44 GP practices and 16 PIPs expressed interest in taking part; all care homes invited agreed to take part. Two thirds of residents approached consented to participate (53/86). Forty residents were recruited (mean age 84 years; 61% (24) were female), and 38 participants remained at 3 months (two died). All GP practices, PIPs and care homes were retained. The number of falls per participating resident was selected as the primary outcome, following assessment of the different outcome measures against predetermined criteria. The chosen secondary outcomes/outcome measures include total falls, drug burden index (DBI), hospitalisations, mortality, activities of daily living (Barthel (proxy)) and quality of life (ED-5Q-5 L (face-to-face and proxy)) and selected items from the STOPP/START guidance that could be assessed without need for clinical judgement. No adverse drug events were reported. The PIP service was generally well received by the majority of stakeholders (care home staff, GPS, residents, relatives and other health care professionals). PIPs reported feeling more confident implementing change following the training but reported challenges accommodating the new service within their existing workload.
Conclusion
Implementing a PIP service in care homes is feasible and acceptable to care home residents, staff and clinicians. Findings have informed refinements to the service specification, PIP training, recruitment to the future RCT and the choice of outcomes and outcome measures. The full RCT with internal pilot started in February 2016 and results are expected to be available in mid late 2020
Production and perception of situationally variable alarm calls in wild tufted capuchin monkeys (Cebus apella nigritus)
Many mammalian and avian species produce conspicuous vocalizations upon encountering a predator, but vary their calling based on risk urgency and/or predator type. Calls falling into the latter category are termed “functionally referential” if they also elicit predator-appropriate reactions in listeners. Functionally referential alarm calling has been well documented in a number of Old World monkeys and lemurs, but evidence among Neotropical primates is limited. This study investigates the alarm call system of tufted capuchin monkeys (Cebus apella nigritus) by examining responses to predator and snake decoys encountered at various distances (reflecting differences in risk urgency). Observations in natural situations were conducted to determine if predator-associated calls were given in additional contexts. Results indicate the use of three call types. “Barks” are elicited exclusively by aerial threats, but the call most commonly given to terrestrial threats (the “hiccup”) is given in nonpredatory contexts. The rate in which this latter call is produced reflects risk urgency. Playbacks of these two call types indicate that each elicits appropriate antipredator behaviors. The third call type, the “peep,” seems to be specific to terrestrial threats, but it is unknown if the call elicits predator-specific responses. “Barks” are thus functionally referential aerial predator calls, while “hiccups” are better seen as generalized disturbance calls which reflect risk urgency. Further evidence is needed to draw conclusions regarding the “peep.” These results add to the evidence that functionally referential aerial predator alarm calls are ubiquitous in primates, but that noncatarrhine primates use generalized disturbance calls in response to terrestrial threats
Utilising Drone Technology in Primatology for 3D Mapping
Emergent Unmanned Aerial System (or drone) technology allows the 3-dimensional mapping of forest landscapes, allowing a new perspective of arboreal primate habitat use. Utilising UASs in primatological studies enables the assessment of habitat quality for different arboreal
primate species, the identification of discreet forms of anthropogenic disturbance (such as historical selective logging), and detailed investigation of canopy use by arboreal primate species. Combining 3D canopy structure with microclimate measurements, we can see how canopy structure buffers solar radiation and how arboreal species may be affected by future climate change. We present data on a study of the arboreal primate community in a lowland section of the Gunung
Leuser Ecosystem in northern Sumatra, focusing on how 3D canopy structure effects ranging (siamang, Symphalangus syndactylus), different primate species’ population densities (lar gibbon, Hylobates lar, siamang and Thomas langur, Presbytis thomasi) and habitat selection (orang-utan,
Pongo abelii and siamang) and how UAS technology can be utilised in other future studies; the potential opportunities, challenges and pitfalls
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