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Radiocarbon (14C) can be used to build absolute chronologies and reconstruct ocean ventilation over the last 40 ka. Sample size requirements have restricted 14C measurements in marine cores with low foraminifer content, impeding 14C-based studies focused on abrupt climate events. Recent developments have demonstrated that small-sized foraminifer samples can now be dated using a gas introduction system at the cost of a small decrease in precision. We explore the potential of gas measurements on benthic and planktonic foraminifers from core SU90-08 (43°03′1″N, 30°02′5″W, 3080 m). Gas measurements are accurate, reproducible within 2σ uncertainty and comparable to graphite measurements. Both techniques yield negative 14C benthic-planktonic (B-P) age-offsets after Heinrich event 1. We argue that negative B-P ages result from bioturbation and changes in foraminifer abundances, with the chance of negative B-P especially increased when the 14C age gradient between the deep and surface waters is decreased. Small-sized 14C measurements seem to capture the variance of the foraminifera age distribution, revealing the active mixing in those archives. Sediment deposition and mixing effects possibly pose a greater obstacle for past 14C-based dating and ocean ventilation reconstructions than the measurement precision itself, particularly in relatively low sedimentation rate settings.
Cancer-related fatigue (CRF) is one of the most commonly reported disease- and treatment-related side effects that impede quality of life. This systematic review and meta-analysis describes the effects of nutrition therapy on CRF and quality of life in people with cancer and cancer survivors. Studies were identified from four electronic databases until September 2017. Eligibility criteria included randomised trials in cancer patients and survivors; any structured dietary intervention describing quantities, proportions, varieties and frequencies of food groups or energy and macronutrient consumption targets; and measures of CRF and quality of life. Standardised mean differences (SMD) were pooled using random-effects models. The American Dietetic Association’s Evidence Analysis Library Quality Checklist for Primary Research was used to evaluate the methodological quality and risk of bias. A total of sixteen papers, of fifteen interventions, were included, comprising 1290 participants. Nutrition therapy offered no definitive effect on CRF (SMD 0·18 (95 % CI –0·02, 0·39)) or quality of life (SMD 0·07 (95 % CI –0·10, 0·24)). Preliminary evidence indicates plant-based dietary pattern nutrition therapy may benefit CRF (SMD 0·62 (95 % CI 0·10, 1·15)). Interventions using the patient-generated subjective global assessment tool and prescribing hypermetabolic energy and protein requirements may improve quality of life. However, the heterogeneity seen in study design, nutrition therapies, quality-of-life measures and cancer types impede definitive dietary recommendations to improve quality of life for cancer patients. There is insufficient evidence to determine the optimal nutrition care plan to improve CRF and/or quality of life in cancer patients and survivors.
Melt electrospinning is a facile fabrication technique that can be utilized in the creation of microfibers without the use of solvent and with good control over feature placement. The available thermal energy of the melt electrospinning technique is often only utilized in the formation of the polymer melt but can also be used to thermodynamically drive chemical reactions. In this study, hybrid perovskite microcrystallites are synthesized in the polymer melt and electrospun to form composite microfibers. Unique hybrid perovskite microstructures were studied, elucidating mechanisms of formation at work in the polymer melt.
Invasive rodents detrimentally affect native bird species on many islands worldwide, and rodent eradication is a useful tool to safeguard endemic and threatened species. However, especially on tropical islands, rodent eradications can fail for various reasons, and it is unclear whether the temporary reduction of a rodent population during an unsuccessful eradication operation has beneficial effects on native birds. Here we examine the response of four endemic land bird species on subtropical Henderson Island in the Pitcairn Island Group, South Pacific Ocean, following an unsuccessful rodent eradication in 2011. We conducted point counts at 25 sampling locations in 14 survey periods between 2011 and 2015, and modelled the abundance trends of all species using binomial mixture models accounting for observer and environmental variation in detection probability. Henderson Reed Warbler Acrocephalus taiti more than doubled in abundance (2015 population estimate: 7,194-28,776), and Henderson Fruit Dove Ptilinopus insularis increased slightly between 2011 and 2015 (2015 population estimate: 4,476–10,072), while we detected no change in abundance of the Henderson Lorikeet Vini stepheni (2015 population estimate: 554–3014). Henderson Crake Zapornia atra increased to pre-eradication levels following anticipated mortality during the operation (2015 population estimate: 4,960–20,783). A temporary reduction of rat predation pressure and rat competition for fruit may have benefitted the reed warbler and the fruit dove, respectively. However, a long drought may have naturally suppressed bird populations prior to the rat eradication operation in 2011, potentially confounding the effects of temporary rat reduction and natural recovery. We therefore cannot unequivocally ascribe the population recovery to the temporary reduction of the rat population. We encourage robust monitoring of island biodiversity both before and after any management operation to better understand responses of endemic species to failed or successful operations.
Bacterial cultures exposed to iron-doped apatite nanoparticles (IDANPs) prior to the introduction of antagonistic viruses experience up to 2.3 times the bacterial destruction observed in control cultures. Maximum antibacterial activity of these bacteria-specific viruses, or phage, occurs after bacterial cultures have been exposed to IDANPs for 1 hr prior to phage introduction, demonstrating that IDANP-assisted phage therapy would not be straight forward, but would instead require controlled time release of IDANPs and phage. These findings motivated the design of an electrospun nanofiber mesh treatment delivery system that allows burst release of IDANPs, followed by slow, consistent release of phage for treatment of topical bacterial infections. IDANPs resemble hydroxyapatite, a biocompatible mineral analogous to the inorganic constituent of mammalian bone, which has been approved by the Food and Drug Administration for many biomedical purposes. The composite nanofiber mesh was designed for IDANP-assisted phage therapy treatment of topical wounds and consists of a superficial, rapid release layer of polyethylene oxide (PEO) fibers doped with IDANPs, followed by inner, coaxial polycaprolactone / polyethylene glycol (PCL/PEG) blended polymer fiber layer for slower phage delivery. Our investigations have established that IDANP-doped PEO fibers are effective vehicles for dissemination of IDANPs for bacterial exposure and resultant increased bacterial death by phage. In this work, slower delivery of the phage behind IDANPs was accomplished using coaxial, electrospun fibers composed of PCL/PEG polymer blend.
Hybrid organic-inorganic perovskites (HOIPs) have been previously compounded with hydrophobic polymers in order to improve the resilience of HOIPs in humid environments. In this study HOIP particles were synthesized and dispersed into a polymer solution. The weight loading of the HOIP phase in the composite was increased until an abrupt change in the electrical conduction was observed indicating a percolation threshold was approached. Additionally, the CH3NH3PbI3/ polystyrene composite media was characterized to assess morphology and the effect it has on the observed electrical properties.
Control of fire was a hallmark of developing human cognition and an essential technology for the colonisation of cooler latitudes. In Europe, the earliest evidence comes from recent work at the site of Cueva Negra del Estrecho del Río Quípar in south-eastern Spain. Charred and calcined bone and thermally altered chert were recovered from a deep, 0.8-million-year-old sedimentary deposit. A combination of analyses indicated that these had been heated to 400–600°C, compatible with burning. Inspection of the sediment and hydroxyapatite also suggests combustion and degradation of the bone. The results provide new insight into Early Palaeolithic use of fire and its significance for human evolution.
Better performance due to repeated testing can bias long-term trajectories of cognitive aging and correlates of change. We examined whether retest effects differ as a function of individual differences pertinent to cognitive aging: race/ethnicity, age, sex, language, years of education, literacy, and dementia risk factors including apolipoprotein E ε4 status, baseline cognitive performance, and cardiovascular risk. We used data from the Washington Heights-Inwood Columbia Aging Project, a community-based cohort of older adults (n=4073). We modeled cognitive change and retest effects in summary factors for general cognitive performance, memory, executive functioning, and language using multilevel models. Retest effects were parameterized in two ways, as improvement between the first and subsequent testings, and as the square root of the number of prior testings. We evaluated whether the retest effect differed by individual characteristics. The mean retest effect for general cognitive performance was 0.60 standard deviations (95% confidence interval [0.46, 0.74]), and was similar for memory, executive functioning, and language. Retest effects were greater for participants in the lowest quartile of cognitive performance (many of whom met criteria for dementia based on a study algorithm), consistent with regression to the mean. Retest did not differ by other characteristics. Retest effects are large in this community-based sample, but do not vary by demographic or dementia-related characteristics. Differential retest effects may not limit the generalizability of inferences across different groups in longitudinal research. (JINS, 2015, 21, 506–518)
Methylation of the fragile X mental retardation 1 (FMR1) exon 1/intron 1 boundary positioned fragile X related epigenetic element 2 (FREE2), reveals skewed X-chromosome inactivation (XCI) in fragile X syndrome full mutation (FM: CGG > 200) females. XCI skewing has been also linked to abnormal X-linked gene expression with the broader clinical impact for sex chromosome aneuploidies (SCAs). In this study, 10 FREE2 CpG sites were targeted using methylation specific quantitative melt analysis (MS-QMA), including 3 sites that could not be analysed with previously used EpiTYPER system. The method was applied for detection of skewed XCI in FM females and in different types of SCA. We tested venous blood and saliva DNA collected from 107 controls (CGG < 40), and 148 FM and 90 SCA individuals. MS-QMA identified: (i) most SCAs if combined with a Y chromosome test; (ii) locus-specific XCI skewing towards the hypomethylated state in FM females; and (iii) skewed XCI towards the hypermethylated state in SCA with 3 or more X chromosomes, and in 5% of the 47,XXY individuals. MS-QMA output also showed significant correlation with the EpiTYPER reference method in FM males and females (P < 0.0001) and SCAs (P < 0.05). In conclusion, we demonstrate use of MS-QMA to quantify skewed XCI in two applications with diagnostic utility.
Teflon amorphous fluoropolymer (TAF) multi-walled carbon nanotube (MWCNT) suspensions have the potential for creating conductive coatings on insulating films for numerous applications. However, there are few studies on polymer MWCNT suspension properties and even fewer that use Teflon. To define mechanical and electrical property relationships, bilayer films of TAF-MWCNT were created with differing concentrations of MWCNTs. Nanoindentation revealed that addition of 8 wt% MWCNTs to TAF increased the elastic modulus by about 25% and hardness by about 15%. Conducting indentation showed 8 wt% MWCNT films exhibit uniform stable conductance once indentation depth exceeds several hundred nanometers. Films with lower concentrations of CNTs were insulating. The two techniques provide a unique description of structure property relationships in this suspension film system.
The draft paper sets out the authors' views of what good practice for the actuarial aspects of internal models will look like in 2012, the year Solvency II is expected to be implemented. Actuaries working on internal models can expect to have to follow such practices if their internal models are to be approved for use in calculating regulatory capital. The paper is therefore relevant for actuaries who plan to work on internal model implementation for Solvency II.
Moreover, the risk quantification techniques discussed in the paper can also be used in the Own Risk Solvency Assessment (ORSA) process also required by Solvency II. The paper is therefore relevant to actuaries working in companies that are not planning to apply to use an internal model.
The paper covers both life and non-life insurance and reinsurance, and reviews current practice as well as setting out possible future practice. This leads to identification of areas for research by the Profession to prepare for 2012 and an indication of the directions this work might take.
The paper is effectively a work in progress, and readers should ask themselves what they should do in response to the ideas discussed.
Pilot studies to test methods to determine the incidence, agents, risk factors and socioeconomic costs of infectious intestinal disease (IID) in England were carried out as recommended by the Committee on the Microbiological Safety of Food (the Richmond Committee) by eight general practices. There were case control and enumeration studies of patients presenting to general practice with IID, a population-based prospective cohort study, and a survey of socioeconomic costs of cases of IID. Information on risk factors was obtained by questionnaire (self-administered compared with interview) and a stool sample was requested on all cases and controls. Response rates in the GP case control study were 75% for case questionnaires and 74% for stools; for controls the figures were 70% and 68% respectively. The acceptance rate into the cohort study was 49%; this was significantly higher where phone contact was made. The rate was similar if recruitment was by individual or household. Follow-up of the cohort by negative reporting was complete for up to 6 months. Direct postage by subject was required to obtain fresh stool specimens. Estimates were obtained of presentation rates of IID and the distribution of risk factors which were used to plan the main study. The pilot study demonstrated that it is possible to undertake a national study based in general practice to determine the incidence of IID in the population and presenting to GPs and its agents, risk factors and costs.
Previous studies have characterized the development of the biological control insects, Galerucella calmariensis and Galerucella pusilla on purple loosestrife and on nontarget Lythraceae species, including two species native to Minnesota, winged loosestrife, and swamp loosestrife. The impact of Galerucella spp. on these plants, when grown in outdoor mesocosms that more closely mimics ecological host range, has not been reported. The first objective of this study was to compare the growth and seed capsule production of purple loosestrife, winged loosestrife, and swamp loosestrife, with and without exposure to Galerucella spp. With purple loosestrife, larval feeding on apical and lateral shoot buds resulted in fewer seed capsules, and reduced aboveground biomass and plant height compared to control plants. No measured plant growth or reproductive parameters were reduced as a result of beetle feeding on swamp loosestrife. Presence of Galerucella spp. on winged loosestrife resulted in a reduction of seed capsules in one of 2 yr of study. A second objective of our study was to compare the phenology of the three Lythraceae species in relation to that of Galerucella spp. In the northern United States, flowering and seed development in swamp loosestrife occurred a month later than in purple or winged loosestrife. The delayed flowering of swamp loosestrife resulted in avoidance of shoot meristem feeding damage caused by the first generation of beetles. Laboratory studies might have overestimated the host range of Galerucella spp. on swamp loosestrife with the finding of asynchronous flowering times of purple and swamp loosestrife. Our mesocosm studies confirm that previous laboratory host range testing did accurately predict the ecological host range of winged loosestrife.
To examine the contribution of genetic factors to food choice, we determined dietary patterns from food frequency questionnaires in 3262 UK female twins aged 18 to 79 years. Five distinct dietary patterns were identified (fruit and vegetable, high alcohol, traditional English, dieting, low meat) that accounted for 22% of the total variance. These patterns are similar to those found in other singleton Western populations, and were related to body mass index, smoking status, physical activity and deprivation scores. Older subjects had higher scores on the fruit and vegetable and traditional English patterns, while lower social deprivation was associated with higher scores for fruit and vegetable, and lower scores for traditional English patterns. All 5 patterns were heritable, with estimates ranging from 41% to 48%. Among individual dietary components, a strongly heritable component was identified for garlic (46%), coffee (41%), fruit and vegetable sources (49%), and red meat (39%). Our results indicate that genetic factors have an important influence in determining food choice and dietary habits in Western populations. The relatively high heritability of specific dietary components implicates taste perception as a possible target for future genetic studies.
Objectives: To demonstrate a potentially life-threatening complication following tonsillectomy in a diabetic patient and discuss the possible pathogenesis.
Methods: Case report and review of the world literature concerning parapharyngeal abscess post-tonsillectomy.
Case report: A 20-year-old female patient underwent an uneventful tonsillectomy following a history of recurrent tonsillitis. She re-presented 14 days post-surgery with a large erythematous tender right mid cervical neck swelling. Clinical and radiological evaluation confirmed a parapharyngeal abscess. She proceeded to have an incision and drainage of the abscess through a horizontal skin crease incision and subsequent intravenous antibiotic therapy. She was discharged home well three days post-surgery.
Conclusion: Diabetes mellitus is a well-recognised systemic disease that may leave an individual more susceptible to infection. We report the first case in a young healthy diabetic patient and highlight a potential serious complication following a routine tonsillectomy.
The success of efforts to re-establish mammalian carnivores within their former range is dependent on three key factors: methodological considerations, the biological requirements of the target species, and the involvement of local human communities for whom large carnivores pose a threat. We consider the role of these factors in the first 13 years of an effort to re-establish wild lions in northern KwaZulu-Natal Province, South Africa. We employed soft-release methods to mitigate the characteristic problems associated with restoration of large carnivores. A pre-release captivity period facilitated acclimatization of reintroduced lions and promoted long-term bonding of unfamiliar individuals into cohesive groups. All individuals remained in the release area and established enduring, stable home ranges. Reintroduced lions successfully reproduced and raised 78% of their cubs to independence. Human activity was the cause of all post-release mortality. Despite rapid population growth and the re-establishment of the species at Phinda Private Game Reserve, the population is small and isolated with little prospect for re-colonizing additional areas where the species has been extirpated, or for connecting with other isolated lion populations in the region. Accordingly, although we essentially overcame the short-term technical and biological challenges facing lion reintroduction, the long-term value of the Phinda population for addressing the conservation issues facing the species remains equivocal.
Osteophagia, variable serum calcium (Ca) and phosphorus (P) concentration, high serum alkaline phosphatase activity, a high growth rate, and a large skeletal mass, all suggest that Ca and P requirements and availability are finely balanced in giraffes. The mineral content of some marker bones in skeletons obtained from adult male giraffes (browsers) and adult male African buffaloes (grazers of similar body mass) were compared to assess the idea of critical Ca and P balance. Our results show that the P concentration of plasma varies more than Ca concentration, and that the Ca content of giraffe bones (0.196±0.01 g/g) and buffalo (0.202±0.006 g/g) varies more than P content (0.095±0.002 in both). The average Ca and P content of the bones analysed was similar in both species (Ca=∼20.0%, P=∼9.5%). Giraffe skeletons, however, contain three times more Ca and P than do buffalo skeletons. This translates into a 1.5–2.0 fold higher Ca requirement for giraffes, with which they seem to cope effectively by selection for Ca-rich, dicotyledonous, browse. Sources of P to meet requirements are not obvious and a seasonal deficiency of P is a more likely cause of observed osteophagia than Ca deficiency. Giraffe rib P density, the best measure of P balance, of 0.142±0.01 g/cm3 is, however, above the deficiency threshold. Bone mineral content (Ca and P) correlates well with bone density and shows only slight differences between adult males of the two species.
Unique features of giraffe Giraffa camelopardalis anatomy are its long neck and slender long limbs. Its neck vertebrae should be light and have low density to make it manoeuvrable while the limb bones should have high density to provide the strength to support the giraffe's mass. Giraffes also have a very high vertical growth rate, a diet with a high Ca:P ratio, and a skeleton that constitutes a high proportion of its body mass. To investigate whether the giraffe skeleton is affected by its anatomy and biology, giraffe bone density and morphology were compared with those of African buffalo Syncerus caffer, an artiodactyl of similar mass, more conventional anatomy, a lower vertical growth rate, and different diet. Our results show that except for minor differences the density of giraffe bones is the same as that of buffaloes. Giraffe limb bones have a slightly greater diameter and much thicker walls than equivalent bones in buffaloes. Giraffe cervical vertebrae, unlike those in buffaloes, decrease in mass with cranial distance. We conclude that giraffe biology and anatomy do not affect bone deposition or density. However, other characteristics of their skeletons seem to be adaptations to their unique anatomy.
Cerebrospinal fluid (CSF) leak following VS removal is a challenging complication. With experience, it can be seen that anatomical factors such as the extent of pneumatization of the petrous temporal bone and posterior wall of the internal auditory canal play animportant role in contributing to CSF leak. Nevertheless, the risk of post-operative CSF leak remains a major concern for both the surgeon and patient. This paper describes a technique, which we have used since 1994, and which has helped us to achieve the lowest reported rate of post-operative CSF leak in translabyrinthine excision of vestibular schwannoma in the world literature.