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A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.
Previous research has shown that problematic parent–child, peer, and romantic partner relationships are associated with an increased likelihood for major depressive disorder (MDD). Less research has evaluated the developmental unfolding of how these interpersonal relationship features are both an antecedent versus a consequence of MDD symptoms from adolescence through young adulthood. These gaps were evaluated using a large community sample (N = 1,127; 54% female, 96% white) via a developmental cascade model. Results showed support for significant antecedent effects, as greater parent–child relationship problems at ages 11 and 17 predicted rank-order increases in MDD symptoms at ages 14 and 20. Supporting a developmental cascade of problematic social relationships, greater parent–child relationship problems at ages 11 and 14 also predicted greater subsequent rank-order increases in antisocial peer affiliation at ages 14 and 17. Greater affiliation to antisocial peers at age 20 predicted greater rank-order increases in romantic relationship problems at age 24, which in turn predicted greater MDD symptoms at age 29. Cross-effects were generally small (βs ≤ .16), illustrating other factors may be relevant to the development or consequences of MDD. Nonetheless, findings support the importance of efforts to strengthen social support networks to offset risk as well as potentially treat depression.
Diet manipulation and genetic selection are two important mitigation strategies for reducing enteric methane (CH4) emissions from ruminant livestock. The aim of this study was to assess whether the diurnal pattern of CH4 emissions from individual dairy cows changes over time when cows are fed on diets varying in forage composition. Emissions of CH4 from 36 cows were measured during milking in an automatic (robotic) milking station in three consecutive feeding periods, for a total of 84 days. In Periods 1 and 2, the 36 cows were fed a high-forage partial mixed ration (PMR) containing 75% forage, with either a high grass silage or high maize silage content. In Period 3, cows were fed a commercial PMR containing 69% forage. Cows were offered PMR ad libitum plus concentrates during milking and CH4 emitted by individual cows was sampled during 8662 milkings. A linear mixed model was used to assess differences among cows, feeding periods and time of day. Considerable variation was observed among cows in daily mean and diurnal patterns of CH4 emissions. On average, cows produced less CH4 when fed on the commercial PMR in feeding Period 3 than when the same cows were fed on high-forage diets in feeding Periods 1 and 2. The average diurnal pattern for CH4 emissions did not significantly change between feeding periods and as lactation progressed. Emissions of CH4 were positively associated with dry matter (DM) intake and forage DM intake. It is concluded that if the management of feed allocation remains constant then the diurnal pattern of CH4 emissions from dairy cows will not necessarily alter over time. A change in diet composition may bring about an increase or decrease in absolute emissions over a 24-h period without significantly changing the diurnal pattern unless management of feed allocation changes. These findings are important for CH4 monitoring techniques that involve taking measurements over short periods within a day rather than complete 24-h observations.
Digital dermatitis is one of the main causes of lameness in dairy cattle, possibly accounting for 25% of the reported cases of lameness (Watson, 1999). With lameness being attributed to reduced milk yields and increased calving intervals there are considerable economic implications and effective treatment and prevention regimes are essential. Topical antibiotic treatment is the most common method of treating digital dermatitis in the UK although there is currently only one product licensed for use (Terramycin spray, Pfizer Animal Health) which contains oxytetracycline. Although effective, there can be various problems (e.g. antibiotic resistance) associated with using antibiotics for the management of digital dermatitis meaning that a suitable prevention regime that uses a non-antibiotic solution instead would be desirable. One possible alternative is sodium chloride solution (salt water) which is hypertonic and would therefore cause the bacterial cells to dehydrate, inhibiting cell growth and multiplication. This trial aimed to investigate the effect of topical application of either oxytetracycline or sodium chloride solution on the pre-washed rear feet of cows for the prevention/treatment of digital dermatitis in dairy cattle.
Children with poor mental health often struggle at school. The relationship between childhood psychiatric disorder and exclusion from school has not been frequently studied, but both are associated with poor adult outcomes. We undertook a secondary analysis of the British Child and Adolescent Mental Health Surveys from 2004 and its follow-up in 2007 to explore the relationship between exclusion from school and psychopathology. We predicted poorer mental health among those excluded.
Psychopathology was measured using the Strengths and Difficulties Questionnaire, while psychiatric disorder was assessed using the Development and Well-Being Assessment and applying Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM IV) criteria. Exclusion from school and socio-demographic characteristics were reported by parents. Multi-variable regression models were used to examine the impact of individual factors on exclusion from school or psychological distress.
Exclusion from school was commoner among boys, secondary school pupils and those living in socio-economically deprived circumstances. Poor general health and learning disability among children and poor parental mental health were also associated with exclusion. There were consistently high levels of psychological distress among those who had experienced exclusion at baseline and follow-up.
We detected a bi-directional association between psychological distress and exclusion. Efforts to identify and support children who struggle with school may therefore prevent both future exclusion and future psychiatric disorder.
One of the most conspicuous phenomena in the Arctic Is the fracture of sea ice. It is scarcely possible to travel far without seeing a variety of fracture forms, produced both by natural processes and by human activity.
At strain-rates below about 10−4 s−1, deformation is dominated by creep, but at higher strain-rates fracture is much more important. One of the reasons for this is the very low fracture toughness of ice. The movements of ice in contact with offshore structures often induce strain-rates well beyond the level at which fracture begins, and so offshore structures will often operate in the fracture regime, and it is fracture processes which will determine the design loads. We consider the different modes of repeated fracture that will occur, and classify them into distinct mechanisms of crushing, spalling, and radial and circumferential cracking. Experimental and field observations are plotted on a deformation mode map. A theoretical treatment of radial cracking confirms that very low loads can propagate cracks to long distances; these loads are small by comparison with those calculated from theoretical models that treat ice as a plastically-deforming continuum.
Several studies in the last decade have explored dramatic instances of refractive fringing in dynamic spectra. We draw attention to a subtler but more widespread refractive effect: wisp-like structures extending (either linearly or with curvature) outward from the origin in the secondary spectrum plane. We have employed a simple pinhole screen simulation to investigate this phenomenon. It appears that the presence of one or more wisps in a secondary spectrum indicates a clump of scattering material that is significantly offset from the optical axis. Unlike the dramatic fringing events that have been investigated in the past, however, the interference that gives rise to a wisp is interference between rays within a scattering clump rather than between two major ray bundles. Furthermore, the scattering clump must be significantly elongated along the direction of pulsar motion. The range of fringe spacings that this produces, all with a similar slope in the secondary spectrum, gives rise to the linear extent of the wisp in the secondary spectrum.
Suicide is a devastating public health problem and very few biological treatments have been found to be effective for quickly reducing the intensity of suicidal ideation (SI). We have previously shown that a single dose of ketamine, a glutamate N-methyl-d-aspartate (NMDA) receptor antagonist, is associated with a rapid reduction in depressive symptom severity and SI in patients with treatment-resistant depression.
We conducted a randomized, controlled trial of ketamine in patients with mood and anxiety spectrum disorders who presented with clinically significant SI (n = 24). Patients received a single infusion of ketamine or midazolam (as an active placebo) in addition to standard of care. SI measured using the Beck Scale for Suicidal Ideation (BSI) 24 h post-treatment represented the primary outcome. Secondary outcomes included the Montgomery–Asberg Depression Rating Scale – Suicidal Ideation (MADRS-SI) score at 24 h and additional measures beyond the 24-h time-point.
The intervention was well tolerated and no dropouts occurred during the primary 7-day assessment period. BSI score was not different between the treatment groups at 24 h (p = 0.32); however, a significant difference emerged at 48 h (p = 0.047). MADRS-SI score was lower in the ketamine group compared to midazolam group at 24 h (p = 0.05). The treatment effect was no longer significant at the end of the 7-day assessment period.
The current findings provide initial support for the safety and tolerability of ketamine as an intervention for SI in patients who are at elevated risk for suicidal behavior. Larger, well-powered studies are warranted.
Resilience is the capacity of individuals to resist mental disorders despite exposure to stress. Little is known about its neural underpinnings. The putative variation of white-matter microstructure with resilience in adolescence, a critical period for brain maturation and onset of high-prevalence mental disorders, has not been assessed by diffusion tensor imaging (DTI). Lower fractional anisotropy (FA) though, has been reported in the corpus callosum (CC), the brain's largest white-matter structure, in psychiatric and stress-related conditions. We hypothesized that higher FA in the CC would characterize stress-resilient adolescents.
Three groups of adolescents recruited from the community were compared: resilient with low risk of mental disorder despite high exposure to lifetime stress (n = 55), at-risk of mental disorder exposed to the same level of stress (n = 68), and controls (n = 123). Personality was assessed by the NEO-Five Factor Inventory (NEO-FFI). Voxelwise statistics of DTI values in CC were obtained using tract-based spatial statistics. Regional projections were identified by probabilistic tractography.
Higher FA values were detected in the anterior CC of resilient compared to both non-resilient and control adolescents. FA values varied according to resilience capacity. Seed regional changes in anterior CC projected onto anterior cingulate and frontal cortex. Neuroticism and three other NEO-FFI factor scores differentiated non-resilient participants from the other two groups.
High FA was detected in resilient adolescents in an anterior CC region projecting to frontal areas subserving cognitive resources. Psychiatric risk was associated with personality characteristics. Resilience in adolescence may be related to white-matter microstructure.
1.1.1 The Faculty of Actuaries' Marketing Research Group was set up in May 1988 to research areas of interest to that new breed of Fellow, the “Marketing Actuary”.
In the initial meetings two general areas of interest were identified—namely the marketing of the actuarial profession, and the marketing of financial services products.
Whilst the group has spent time on both subjects this first paper is concerned with the marketing of the actuarial profession.
1.1.2 We felt that the starting point for a marketing audit of the profession was to conduct research amongst the members. In addition we have investigated the coverage achieved by the profession in the media, and looked into developments in North America, including a survey which ranked the actuarial profession against other forms of employment.
Methane (CH4) emissions by dairy cows vary with feed intake and diet composition. Even when fed on the same diet at the same intake, however, variation between cows in CH4 emissions can be substantial. The extent of variation in CH4 emissions among dairy cows on commercial farms is unknown, but developments in methodology now permit quantification of CH4 emissions by individual cows under commercial conditions. The aim of this research was to assess variation among cows in emissions of eructed CH4 during milking on commercial dairy farms. Enteric CH4 emissions from 1964 individual cows across 21 farms were measured for at least 7 days/cow using CH4 analysers at robotic milking stations. Cows were predominantly of Holstein Friesian breed and remained on the same feeding systems during sampling. Effects of explanatory variables on average CH4 emissions per individual cow were assessed by fitting a linear mixed model. Significant effects were found for week of lactation, daily milk yield and farm. The effect of milk yield on CH4 emissions varied among farms. Considerable variation in CH4 emissions was observed among cows after adjusting for fixed and random effects, with the CV ranging from 22% to 67% within farms. This study confirms that enteric CH4 emissions vary among cows on commercial farms, suggesting that there is considerable scope for selecting individual cows and management systems with reduced emissions.
This paper presents the results of research into the marketing of the actuarial profession including a SWOT analysis, public awareness and image of the profession amongst target groups (general public, undergraduates, journalists, company directors, pension scheme trustees and insurance intermediaries), and the desire to allocate more resources to the profession's public awareness and image. The paper also contains an analysis of the national press coverage achieved by the profession and reports on developments in North America where a task force on strengthening the actuarial profession has been set up.
The current study explored longitudinal associations between interparental aggression, the development of child attention skills, and early childhood behavior problems in a diverse sample of 636 families living in predominately low-income, nonmetropolitan communities. The results of latent-variable, cross-lagged longitudinal models revealed that maternal-reported interparental aggression in infancy predicted reduced observed attention skills in toddlerhood; no association was observed, however, between attention in infancy and interparental aggression during the toddler years. Further, reduced toddler attention and high interparental aggression were both associated with increased risk for attention-deficit/hyperactivity disorder symptoms and conduct problems at 3 years of age. Processes largely operated in similar ways regardless of child gender or low-income status, although a few differences were observed. Overall, the results suggest that interparental aggression undermines attention development, putting children's early behavioral adjustment at risk.
After discussions of multilayer relaxation for monatomic metallic surfaces and low-energy electron diffraction (LEED) procedures, some available results concerning the atomic structure of alloy surfaces are reviewed briefly. Results are discussed only for surfaces of ordered binary alloys and crystalline, substitutionally random binary alloys. Surfaces for which detailed results are available are highlighted as examples which illustrate some general crystallographic effects that occur at alloy surfaces. Specific effects included in the examples are the rippling of atomic constituents in the surface layers of ordered alloys, the preferential termination of alloys by a specific type of layer where more than one type of layer exists in the bulk, a mixture of two possible terminations, and the alternating enrichment and depletion of an atomic constituent in the surface layers of alloys which are disordered in the bulk.
Optical second harmonic generation is a new surface diagnostic applicable both in ultra-high vacuum and ambient environments and capable of examining gas-solid, liquid-solid and solid-solid interfaces. Studies of surface segregation of chromium and nitrogen on Fe-18Cr-3Mo(II0) single crystal surfaces in ultra-high vacuum are described. Major increases in second harmonic intensity generated by 700 nm excitation at the surface are seen upon heating to temperatures at which chromium and nitrogen cosegregate. Adsorption of oxygen has also been studied on this surface. Second harmonic generation shows promise in providing structural and electronic information for surfaces and interfaces in a wide variety of environments.
During the growth of the first monolayer, Cu has been shown to form in 2d islands pseudomorphic to the Ru 0001) surface under a tensile strain of -6%. The chemical behavior of such films has been found to be unlike that of either of the pure elements both from the standpoint of catalytic activity and molecular adsorption properties. In addition, these strainedlayer films have unique electronic properties. Specifically, we have identified a set of interface and surface states near the K point in the surface Brillioun zone. Here are shown new results concerning the behavior of the interface states with respect to CO adsorption. Specifically, CO is found to attenuate all Cu/Ru ARUPS structures except those due to the antibonding components of the interface states and these components move to higher binding energy with CO coverage. An analysis of these results, based on the properties of the interface states, indicates that there is negligible direct interaction between the CO orbitals and the metal d states. The increased bonding that is seen for CO on Cu/Ru compared to CO on Cu is suggested to result from an enchanced polarizability of the Cu 4s states due to the proximity of the Ru substate.
Carbon monoxide chemisorption on the (111) and (110) surfaces of a single-crystal NiAI alloy has been studied using several surface sensitive techniques, including work function change measurements, ultra-violet photoelectron, thermal desorption and electron energy loss spectroscopy. Results from these experiments indicate that the reactivity of these NiAI surfaces toward CO is distinctly different and that although the CO/NiAI (111) surface behaves more like CO adsorbed on pure nickel surfaces, the CO/NiAI (110) surface is neither like CO adsorbed on pure nickel nor aluminum surfaces. The local CO bonding sites, as probed with photoemission and electron energy loss spectroscopy, are similar on both NiAI surfaces.