Do astigmatid teeth matter: a tribological review of cheliceral chelae in co-occuring mites from UK beehives

The dentition of the chelal moveable digit in cohabiting astigmatids from UK beehives (i.e., Carpoglyphus lactis (Linnaeus), Glycyphagus domesticus (DeGeer), and Tyrophagus putrescentiae (Schrank)) is characterised for the first time using quantitative tribological measures within a 2D mechanical model. The trophic function of astigmatid chelae are reviewed in terms of macroscopic tools used by humans including hooking devices, pliers, shears, rasps and saws. Comparisons to oribatid claws and isopod dactyli are made. The overall pattern of the moveable digit form of T.putrescentiae is not just a uniformly shrunken/swollen version between the other two taxa at either the macro- or micro-scale. Mastication surface macro-roughness values are in the range of international Roughness Grade Numbers N5 − N6. The moveable digit of C.lactis has low rugosity values compared to the glycyphagid and acarid (which are topographically more similar and match that roughness typical of some coral reef surfaces). C.lactis has the most plesiomorphic moveable digit form. The mastication surface of all three species as a chewing tool is distinctly ornamented despite the moveable digit of C.lactis looking like a bar-like beam. The latter has more opportunities to be a multifunctional tool behaviourally than the other two species. Little evidence of any differences in the ‘spikiness’ of any ‘toothiness’ is found. Some differences with laboratory cultured specimens are found in C.lactis and possibly T.putrescentiae suggesting where selection on the digit may be able to occur. The chelal surface of T.putrescentiae has been deformed morphologically during evolution the most, that of C.lactis the least. Repeated localised surface differentiation is a feature of the moveable digit in G.domesticus compared to the likely more concerted changes over certain nearby locations in T.putrescentiae. An impactful chelal teeth design is present in G.domesticus but this is more equivocal in T.putrescentiae. Pockets within the mastication surface of the glycyphagid (and to some extent for the acarid) may produce foodstuff crunch forces of the scale of the chelal tips of oribatids. The moveable digit dentition of G.domesticus is adapted to shred foodstuf (like a ripsaw) more than that of the grazing/shearing dentition of T.putrescentiae. The collecting ‘picker‘ design of C.lactis posterior teeth matches the size of Bettsia alvei hyphae which attacks hive-stored pollen. Detritus accumulated in chelal digit gullets through a sawing action matches the smallest observed ingested material. The dentition of C.lactis should produce less friction when moving through food material than G.domesticus. C.lactis is the most hypocarnivorous and may ‘skim’ through fluids when feeding. Astigmatid teeth do matter. The three commensal species can avoid direct competition. Future work is proposed in detail

Variation in the trophic morphology of astigmatid mites common in UK beehives

The chelal moveable digit in Carpoglyphus lactis (Linnaeus), Glycyphagus domesticus (DeGeer), and Tyrophagus putrescentiae (Schrank) from UK beehives is described using quantitative measures within a 2D mechanical model. The location of maximum jerk on the profile of the chelal moveable digit indicates the end of the mastication surface, which in these mites is confirmed to be just before the theoretical cut-off point for a functioning chewing `machine`. All three species should be able to grasp yeasts, spores and mycelial hyphae in the hive. The moveable digit of C. lactis may be designed to enable pollenophagy. The mastication surface is 21.3 μm in C. lactis, 18.8 μm in G. domesticus, and 17.2 μm in T. putrescentiae. The wild-collected C. lactis shows the smallest chelal moveable digit tip velocity ratios (i.e., the lowest relative length of input to output moment arms). Glycyphagus domesticus has the most primitive geometry of its chela. The depth of the moveable digit matches the inferred resistive forces applied by the mite to food at that point. Condylar and moveable digit strengthening by sclerotisation is associated with eating tougher food. Effective chelal gape is 28.7 μm in C. lactis, 25.9 μm in G. domesticus and 24.8 μm in T. putrescentiae. Maximum food fragment size grabbed by the chela is estimated as 7786 μm3 in C. lactis, 5348 μm3 in G. domesticus and 4703 μm3 in T. putrescentiae. Morsel size pre-ingestion is estimated as 4031 μm3 in C. lactis, 5228 μm3 in G. domesticus and 4246 μm3 in T. putrescentiae. Under reasonable assumptions one of these mites might be able to excavate its own body volume equivalent in about one hour

Transitional chelal digit patterns in saprophagous astigmatan mites

Changes in the functional shape of astigmatan mite moveable digit profiles are examined to test if Tyrophagus putrescentiae (Acaridae) is a trophic intermediate between a typical micro-saprophagous carpoglyphid (Carpoglyphus lactis) and a common macro-saprophagous glycyphagid (Glycyphagus domesticus). Digit tip elongation in these mites is decoupled from the basic physics of optimising moveable digit inertia. Investment in the basal ramus/coronoid process compared to that for the moveable digit mastication length varies with feeding style. A differentiated ascending ramus is indicated in C. lactis and in T. putrescentiae for different trophic reasons. Culturing affects relative investments in C. lactis. A markedly different style of feeding is inferred for the carpoglyphid. The micro-saprophagous acarid does not have an intermediate pattern of trophic functional form between the other two species. Mastication surface shape complexity confirms the acarid to be heterodontous. T. putrescentiae is a particularly variably formed species trophically. A plausible evolutionary path for the gradation of forms is illustrated. Digit form and strengthening to resist bending under occlusive loads is explored in detail. Extensions to the analytical approach are suggested to confirm the decoupling of moveable digit pattern from cheliceral and chelal adaptations. Caution is expressed when interpreting ordinations of multidimensional data in mites

Looking for future biological control agents: the comparative function of the deutosternal groove in mesostigmatid mites

The physics of fluid laminar flow through an idealised deutosternum assembly is used for the first time to review predatory feeding designs over 72 different-sized example species from 16 mesostigmatid families in order to inform the finding of new biological control agents. Gnathosomal data are digitised from published sources. Relevant gnathosomal macro- and micro-features are compared and contrasted in detail which may subtly impact the control of channel- or ‘pipe’-based transport of prey liquids around various gnathosomal locations. Relative deutosternal groove width on the mesostigmatid subcapitulum is important but appears unrelated to the closing velocity ratio of the moveable digit. Big mites are adapted for handling large and watery prey. The repeated regular distance between deutosternal transverse ridges (‘Querleisten’) supports the idea of them enabling a regular fluctuating bulging or pulsing droplet-based fluid wave ‘sticking’ and ‘slipping’ along the groove. Phytoseiids are an outlier functional group with a low deutosternal pipe flow per body size designed for slot-like microchannel transport in low volume fluid threads arising from daintily nibbling nearby prey klinorhynchidly. Deutosternal groove denticles are orientated topographically in order to synergise flow and possible mixing of coxal gland-derived droplets and circumcapitular reservoir fluids across the venter of the gnathosomal base back via the hypostome to the prey being masticated by the chelicerae. As well as working with the tritosternum to mechanically clean the deutosternum, denticles may suppress fluid drag. Shallow grooves may support edge-crawling viscous flow. Lateral features may facilitate handling unusual amounts of fluid arising from opportunistic feeding on atypical prey. Various conjectures for confirmatory follow-up are highlighted. Suggestions as to how to triage non-uropodoid species as candidate plant pest control agents are included

Using Spatio-temporal Modelling as a Decision Support Tool for Management of a Native Pest Herbivore

Landscape modification can alter the distribution and abundance of wildlife, which can result in irruptions of native species causing significant impacts on economically and ecologically valuable systems. This study investigated the applications of the Spatio- Temporal Animal Reduction (STAR) model, originally designed for the management of feral ungulates, by adapting it for the management of a native pest herbivore (the Tasmanian pademelon, Thylogale billardierii) within an agricultural-forest mosaic, typical of Tasmanian (Australian) agricultural landscapes. Empirical data of habitat and demographic features of a pest population were inputted into STAR to test the cost-effectiveness of three simulated density reduction models. Compared with the projected population growth under no management, simulations demonstrated that low, medium and high density reduction all reduced population abundance over 10 years. Cost increased with the level of population reduction due to increasing difficulty with locating individuals. The revenue gained from a simulated harvest was greatest for medium-intensity density reduction. We propose STAR can be used as a decision support tool to guide situations considering resource availability, browsing intensity and site- specific management objectives. The application of STAR highlights the model’s adaptability across diverse pest populations, landscape features and where there is competition for resources between domestic and native populations

Antipsychotic prescribing in care homes before and after launch of a national dementia strategy:an observational study in English institutions over a 4-year period

Objectives To assess associations between the launch of the National Dementia Strategy (NDS) and antipsychotic prescribing in long-term residential care (LTC) in England. Setting and participants Retrospective analysis of prescribing patterns in 616 LTC institutions (31 619 residents) following launch of the NDS, using information from electronic medicines management system. Primary and secondary outcome measures Antipsychotic prescribing point prevalence (PP) for all residents in a cross section of LTC settings over a 4-year period following NDS launch. Secondary outcomes included dosages, length of treatment and use of recommended second-generation antipsychotics (SGAs) versus first-generation antipsychotics (FGAs). Associations between facility-level PP values and institutional characteristics, resident demographics were explored. Variations across geographical areas examined. Prescription net ingredient costs calculated. Results No statistically significant difference was observed in overall prescribing rates over the 4-year period (Kolmogorov-Smirnov (KS) test p=0.60), and there was no significant shift towards newer SGAs (KS test p=0.32). Dosages were above the maximum indicated in only 1.3% of cases, but duration of prescribing was excessive in 69.7% of cases. Care homes in the highest prescribing quintile were more likely to be located in a deprived area (rate ratio (Q5/Q1) RR=5.89, 95% CI 4.35 to 7.99), registered for dementia (RR=3.38, 95% CI 3.06 to 3.73) and those in the lowest quintile were more likely to be served by a single general practitioner (GP) practice (RR=0.48; 95% CI 0.37 to 0.63); p<0.001 all. A sixfold variation in PP levels was observed between geographical areas. The average annual expenditure on antipsychotics was £65.6 per person resident (2012 prices). Conclusions The NDS in England was not associated with reduced PP levels or the types of antipsychotic prescribing in care homes. Further research is needed to explore why. Clear standards specifying recommended agents, dosages and length of treatment, together with routine monitoring and greater accountability for antipsychotic prescribing, may be required

A two-phase model for smoothly joining disparate growth phases in the macropodid Thylogale billardierii

Generally, sigmoid curves are used to describe the growth of animals over their lifetime. However, because growth rates often differ over an animal's lifetime a single curve may not accurately capture the growth. Broken-stick models constrained to pass through a common point have been proposed to describe the different growth phases, but these are often unsatisfactory because essentially there are still two functions that describe the lifetime growth. To provide a single, converged model to age animals with disparate growth phases we developed a smoothly joining two-phase nonlinear function (SJ2P), tailored to provide a more accurate description of lifetime growth of the macropod, the Tasmanian pademelon Thylogale billardierii. The model consists of the Verhulst logistic function, which describes pouch-phase growth--joining smoothly to the Brody function, which describes post-pouch growth. Results from the model demonstrate that male pademelons grew faster and bigger than females. Our approach provides a practical means of ageing wild pademelons for life history studies but given the high variability of the data used to parametrise the second growth phase of the model, the accuracy of ageing of post-weaned animals is low: accuracy might be improved with collection of longitudinal growth data. This study provides a unique, first robust method that can be used to characterise growth over the lifespan of pademelons. The development of this method is relevant to collecting age-specific vital rates from commonly used wildlife management practices to provide crucial insights into the demographic behaviour of animal populations.Financial support was provided by the Tasmanian Community Forest Agreement: Alternatives to 1080 Programme. In-kind support was provided by the University of Tasmania

Provision of NHS generalist and specialist services to care homes in England: review of surveys

Background: The number of beds in care homes (with and without nurses) in the United Kingdom is three times greater than the number of beds in National Health Service (NHS) hospitals. Care homes are predominantly owned by a range of commercial, not-for-profit or charitable providers and their residents have high levels of disability, frailty and co-morbidity. NHS support for care home residents is very variable, and it is unclear what models of clinical support work and are cost-effective. Objectives: To critically evaluate how the NHS works with care homes.MethodsA review of surveys of NHS services provided to care homes that had been completed since 2008. It included published national surveys, local surveys commissioned by Primary Care organisations, studies from charities and academic centres, grey literature identified across the nine government regions, and information from care home, primary care and other research networks. Data extraction captured forms of NHS service provision for care homes in England in terms of frequency, location, focus and purpose. Results: Five surveys focused primarily on general practitioner services, and 10 on specialist services to care home. Working relationships between the NHS and care homes lack structure and purpose and have generally evolved locally. There are wide variations in provision of both generalist and specialist healthcare services to care homes. Larger care home chains may take a systematic approach to both organising access to NHS generalist and specialist services, and to supplementing gaps with in-house provision. Access to dental care for care home residents appears to be particularly deficient. Conclusions:Historical differences in innovation and provision of NHS services, the complexities of collaborating across different sectors (private and public, health and social care, general and mental health), and variable levels of organisation of care homes, all lead to persistent and embedded inequity in the distribution of NHS resources to this population. Clinical commissioners seeking to improve the quality of care of care home residents need to consider how best to provide fair access to health care for older people living in a care home, and to establish a specification for service delivery to this vulnerable population

A Two-Phase Model for Smoothly Joining Disparate Growth Phases in the Macropodid Thylogale billardierii

Generally, sigmoid curves are used to describe the growth of animals over their lifetime. However, because growth ratesoften differ over an animal&rsquo;s lifetime a single curve may not accurately capture the growth. Broken-stick models constrainedto pass through a common point have been proposed to describe the different growth phases, but these are oftenunsatisfactory because essentially there are still two functions that describe the lifetime growth. To provide a single,converged model to age animals with disparate growth phases we developed a smoothly joining two-phase nonlinearfunction (SJ2P), tailored to provide a more accurate description of lifetime growth of the macropod, the Tasmanianpademelon Thylogale billardierii. The model consists of the Verhulst logistic function, which describes pouch-phase growth&ndash; joining smoothly to the Brody function, which describes post-pouch growth. Results from the model demonstrate thatmale pademelons grew faster and bigger than females. Our approach provides a practical means of ageing wildpademelons for life history studies but given the high variability of the data used to parametrise the second growth phaseof the model, the accuracy of ageing of post-weaned animals is low: accuracy might be improved with collection oflongitudinal growth data. This study provides a unique, first robust method that can be used to characterise growth overthe lifespan of pademelons. The development of this method is relevant to collecting age-specific vital rates fromcommonly used wildlife management practices to provide crucial insights into the demographic behaviour of animalpopulations

A systematic review and meta-synthesis of the impact of low back pain on people's lives

Copyright @ 2014 Froud et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.Background - Low back pain (LBP) is a common and costly problem that many interpret within a biopsychosocial model. There is renewed concern that core-sets of outcome measures do not capture what is important. To inform debate about the coverage of back pain outcome measure core-sets, and to suggest areas worthy of exploration within healthcare consultations, we have synthesised the qualitative literature on the impact of low back pain on people’s lives. Methods - Two reviewers searched CINAHL, Embase, PsycINFO, PEDro, and Medline, identifying qualitative studies of people’s experiences of non-specific LBP. Abstracted data were thematic coded and synthesised using a meta-ethnographic, and a meta-narrative approach. Results - We included 49 papers describing 42 studies. Patients are concerned with engagement in meaningful activities; but they also want to be believed and have their experiences and identity, as someone ‘doing battle’ with pain, validated. Patients seek diagnosis, treatment, and cure, but also reassurance of the absence of pathology. Some struggle to meet social expectations and obligations. When these are achieved, the credibility of their pain/disability claims can be jeopardised. Others withdraw, fearful of disapproval, or unable or unwilling to accommodate social demands. Patients generally seek to regain their pre-pain levels of health, and physical and emotional stability. After time, this can be perceived to become unrealistic and some adjust their expectations accordingly. Conclusions - The social component of the biopsychosocial model is not well represented in current core-sets of outcome measures. Clinicians should appreciate that the broader impact of low back pain includes social factors; this may be crucial to improving patients’ experiences of health care. Researchers should consider social factors to help develop a portfolio of more relevant outcome measures.Arthritis Research U