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The association between schizophrenia and decreased vitamin D levels is well documented. Low maternal and postnatal vitamin D levels suggest a possible etiological mechanism. Alternatively, vitamin D deficiency in patients with schizophrenia is presumably (also) the result of disease-related factors or demographic risk factors such as urbanicity.
In a study population of 347 patients with psychotic disorder and 282 controls, group differences in vitamin D concentration were examined. Within the patient group, associations between vitamin D, symptom levels and clinical variables were analyzed. Group × urbanicity interactions in the model of vitamin D concentration were examined. Both current urbanicity and urbanicity at birth were assessed.
Vitamin D concentrations were significantly lower in patients (B = −8.05; 95% confidence interval (CI) −13.68 to −2.42; p = 0.005). In patients, higher vitamin D concentration was associated with lower positive (B = −0.02; 95% CI −0.04 to 0.00; p = 0.049) and negative symptom levels (B = −0.03; 95% CI −0.05 to −0.01; p = 0.008). Group differences were moderated by urbanicity at birth (χ2 = 6.76 and p = 0.001), but not by current urbanicity (χ2 = 1.50 and p = 0.224). Urbanicity at birth was negatively associated with vitamin D concentration in patients (B = −5.11; 95% CI −9.41 to −0.81; p = 0.020), but not in controls (B = 0.72; 95% CI −4.02 to 5.46; p = 0.765).
Lower vitamin D levels in patients with psychotic disorder may in part reflect the effect of psychosis risk mediated by early environmental adversity. The data also suggest that lower vitamin D and psychopathology may be related through direct or indirect mechanisms.
Orbital-free density functional theory (OFDFT) is both grounded in quantum physics and suitable for direct simulation of thousands of atoms. This article describes the application of OFDFT for materials research over roughly the past two decades, highlighting computational studies that would have been impractical (or impossible) to perform with other techniques. In particular, we review the growing body of simulations of solids and liquids that have been conducted with planewave-pseudopotential (or related) techniques. We also provide an updated account of the fundamentals of OFDFT, emphasizing aspects—such as nonlocal density functionals for computing the kinetic energy of noninteracting electrons—that enabled much of the application work. The article concludes with a discussion of the OFDFT frontier, which contains brief descriptions of other topics at the forefront of OFDFT research.
A significant proportion of the grass silage fed to lactating dairy cows may be of only modest quality due either to delayed harvesting and/or poor ensiling conditions. In such situations, both total feed intake and milk production are likely to be compromised with the consequent need to feed more concentrates. Part of this effect is considered to be due to the development of a solid mass of digesta in the rumen, with loss of the normal layered or biphasic stratification of rumen contents. Under such conditions, rumen motility, rate of forage digestion and hence voluntary feed intake will be compromised. Mertens (1997) stressed that chemical definition of dietary fibre such as neutral- (NDF) or acid-detergent (ADF) fibre content was an inadequate description of the fibre content of a diet as it affects rumen function and animal performance. Consequently he proposed both effective NDF (eNDF; ability of a feed to replace a roughage with no negative effect on milk fat content) and physically effective NDF (peNDF; a measure of the physical properties of fibre as it stimulates chewing activity and development of the biphasic stratification of rumen contents) as additional descriptors of the physical characteristics of dietary fibre but to date these concepts have attracted limited attention in the UK. This study examined the effect of replacing increasing amounts of grass silage (GS) on a dry matter (DM) basis in a silage:concentrate ration with pressed sugar beet pulp (PP) on various processes of digestion in the rumen of lactating dairy cows, specifically in relation to chewing activity and rumen mat density.
The in sacco technique has been successfully utilised to differentiate feedstuffs in terms of their rate and extent of degradation. However, the large initial particle losses associated with the requirement to finely divide the substrates prior to incubation and the inability of the technique to examine liquid feed supplements has led to alternative methodologies being adopted. This study examined the ability of the Reading Pressure Technique (RPT) to differentiate a number of minimally processed energy supplements, in terms of their rate of degradation.
Intensively finished beef cattle have traditionally been fed rations based on rolled mineralised barley with a protein supplement such as soya bean or rapeseed meal. Since feed accounts for 75-85% of the variable costs of intensive beef production systems (MLC 1999) the use of alternative feeds that have a lower cost per unit of energy are worthy of investigation. The objective of this trial was to evaluate feeding pressed sugar beet pulp ensiled with dried maize distillers grains (Praize, Trident Feeds) on the performance of fast finishing continental cross weaned suckled bulls.
Dairy cows are increasingly being fed high levels of starch to increase energy intake and promote milk protein content. However, too high levels of degradable starch can cause rumen acidotic effects leading to poor rumen health, laminitis and ultimately reduced efficiency of milk production. Fibrous feeds have known benefits on rumen health by helping to buffer rumen pH, but little is known of the effects of replacing starch with fibre in high maize silage based rations for dairy cows. The objective of this trial was to determine the effects of incremental replacement of cereal grain with sugar beet feed in a total mixed ration on dry matter intake, milk yield, milk composition and yield of milk constituents of lactating dairy cows receiving a high starch diet based on maize silage.
Maize distillers grains (MDG) is a high quality by-product feed containing 317 g crude protein (CP)/kg DM and 13.5 MJ metabolisable energy/kg DM, and as such is a valuable traceable feed resource. An earlier study conducted at the Centre for Dairy Research (Sutton et al. 2000) with cows in late lactation using a total mixed ration (TMR) based on maize silage, compared the protein value of MDG with that of soyabean meal (SB). The study showed that MDG could be used to replace SB on a total nitrogen (TN) basis without effecting feed intake or nutrient digestion in the rumen, or flow of non-ammonia nitrogen to the duodenum. The aim of the current study was to determine the effect of replacing SB with MDG on a TN basis, on DM intake and milk production in high yielding lactating dairy cows.
Feeding of lowland sheep on straw-based systems during pregnancy and in early lactation has shown that ewe and lamb performance can be satisfactory, providing adequate compound supplementation is fed (Davies and Chapple, 1995). Whole barley and soya bean meal has been the standard ration. However, soya bean meal is imported and not fully traceable. Experiments with January- and March-lambing ewes have shown that traceable, homeproduced feeds based on equal quantities of molassed sugar beet feed and either maize or barley distillers grains can replace a barley/soya supplement when fed with straw or silage-based diets in late pregnancy (Chapple et al., 1998 and 1999). The objective of this work was to evaluate the effects on ewe and lamb performance of feeding sugar beet feeds with distillers grains to March-lambing ewes rearing twin lambs at pasture.
Lameness in the dairy cow not only causes major financial loss but also has serious welfare implications. Both environmental and nutritional factors have been implicated in its occurrence, which is commonly observed as laminitis, white line disease and sole ulcers, which are disorders of the corium. The aim of the current study was to examine the effect of diet composition in the form of non-structural carbohydrates on hoof health.
Feeding lowland sheep on straw-based systems during pregnancy (Davies and Chapple 1995) has shown that ewe and lamb performance can be satisfactory, providing adequate compound supplementation was fed. Whole barley and soya bean meal has been the standard ration. Experiments with March-lambing ewes (Chapple et al., 1997) has shown that feeds based on molassed sugar beet feed and maize distillers dark grains can replace a barley/soya supplement. The objective of this work was to evaluate the effects on ewe and lamb performance of feeding sugar beet feeds with higher levels of distillers grains to January-lambing ewes on straw-based and big-bale silage systems during pregnancy and early lactation.
The complete replacement of soyabean meal by maize distillers grains (MDG) in dairy cow diets had no significant effects on milk production, rumen digestion or the supply of non-ammonia N to the duodenum (Sutton et al., 2000; Phipps et al., 2001). The present experiment was designed to extend this work by examining the response when barley (BDG) or wheat (WDG) distillers grains replaced soyabean meal.
Lamb concentrate costs account for around 30% of the variable costs of an early lambing system and can account for up to 33% of the variable costs for store lamb finishing (MLC, 2000). Over recent years the price for finished lambs has declined. It is against this background of declining lamb prices and reduced gross margins that cheaper alternatives to proprietary lamb concentrates are being sought. The aim of this work was to evaluate an ensiled mix of pressed sugar beet pulp and dried maize distillers dark grains (Praize, Trident Feeds Limited) for finishing lambs.
Feeding of lowland sheep on straw-based systems during pregnancy and in early lactation has shown that ewe and lamb performance can be satisfactory, providing adequate compound supplementation is fed (Davies and Chapple, 1995). Whole barley and soya bean meal has been the standard ration. However, soya bean meal is imported and may not be fully traceable. Maize or barley distillers fed with beans could provide traceable protein to replace soya bean meal in sheep diets. Experiments with housed early-lambing ewes and ewes suckling twin lambs at grass have shown that traceable feeds, based on molassed sugar beet and either maize or barley distillers grains, can replace a barley/soya supplement when fed with straw based diets in late pregnancy or at grass (Chapple et al., 1999 and 2000). The objective of this work was to evaluate the effects on ewe and lamb performance of feeding sugar beet feeds with distillers grains and beans to March-lambing ewes on a straw-based system.
Extracted soya-bean meal is used by many beef producers in the UK as a protein source for cattle. A number of farm assurance schemes and abattoirs now prohibit the use of this feedstuff due to the possible inclusion of genetically modified material. Organic production standards prohibit the feeding of solvent extracted feeding stuffs. Therefore, there is a requirement to evaluate alternative traceable protein sources for beef cattle. The objective of this trial was to determine the effect on cattle performance of feeding sugar beet feed with distillers grains or soya-bean meal to beef cattle on a silage based system.
Maize distillers grains (MDG) are a traceable and valuable energy and protein feed for dairy cows (Owen and Larson, 1991) but little is known about the ability of UK MDG to replace more conventional protein sources, particularly their effects on the supply of protein to the cow. The purpose of the present experiment was to examine the effects of replacing soyabean meal with MDG on digestion in the rumen and flow of protein to the duodenum of lactating dairy cows.
This paper presents latest thinking from the Institute and Faculty of Actuaries’ Model Risk Working Party and follows on from their Phase I work, Model Risk: Daring to Open the Black Box. This is a more practical paper and presents the contributors’ experiences of model risk gained from a wide range of financial and non-financial organisations with suggestions for good practice and proven methods to reduce model risk. After a recap of the Phase I work, examples of model risk communication are given covering communication: to the Board; to the regulator; and to external stakeholders. We present a practical framework for model risk management and quantification with examples of the key actors, processes and cultural challenge. Lessons learned are then presented from other industries that make extensive use of models and include the weather forecasting, software and aerospace industries. Finally, a series of case studies in practical model risk management and mitigation are presented from the contributors’ own experiences covering primarily financial services.
Children and adolescents are a vulnerable group to develop post-traumatic stress symptoms after natural or man-made disasters. In the light of increasing numbers of refugees under the age of 18 years worldwide, there is a significant need for effective treatments. This meta-analytic review investigates specific psychosocial treatments for children and adolescents after man-made and natural disasters. In a systematic literature search using MEDLINE, EMBASE and PsycINFO, as well as hand-searching existing reviews and contacting professional associations, 36 studies were identified. Random- and mixed-effects models were applied to test for average effect sizes and moderating variables. Overall, treatments showed high effect sizes in pre–post comparisons (Hedges' g = 1.34) and medium effect sizes as compared with control conditions (Hedges' g = 0.43). Treatments investigated by at least two studies were cognitive–behavioural therapy (CBT), eye movement desensitization and reprocessing (EMDR), narrative exposure therapy for children (KIDNET) and classroom-based interventions, which showed similar effect sizes. However, studies were very heterogenic with regard to their outcomes. Effects were moderated by type of profession (higher level of training leading to higher effect sizes). A number of effective psychosocial treatments for child and adolescent survivors of disasters exist. CBT, EMDR, KIDNET and classroom-based interventions can be equally recommended. Although disasters require immediate reactions and improvisation, future studies with larger sample sizes and rigorous methodology are needed.
The aim of this study was to assess the efficacy of meaning-centered group psychotherapy for cancer survivors (MCGP-CS) to improve personal meaning, compared with supportive group psychotherapy (SGP) and care as usual (CAU).
A total of 170 cancer survivors were randomly assigned to one of the three study arms: MCGP-CS (n = 57); SGP (n = 56); CAU (n = 57). The primary outcome measure was the Personal Meaning Profile (PMP; total score). Secondary outcome measures were subscales of the PMP, psychological well-being (Scales of Psychological Well-being; SPWB), post-traumatic growth (Posttraumatic Growth Inventory), Mental Adjustment to Cancer (MAC), optimism (Life Orientation Test-Revised), hopelessness (Beck's Hopelessness Scale), psychological distress (anxiety and depression, Hospital Anxiety and Depression Scale; HADS) and quality of life (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire; EORTC QLQ-C30). Outcome measures were assessed before randomization, post-intervention, and after 3 and 6 months of follow-up (FU).
Linear mixed model analyses (intention-to-treat) showed significant differences between MCGP-CS, SGP and CAU on the total PMP score, and on (sub)scales of the PMP, SPWB, MAC and HADS. Post-hoc analyses showed significantly stronger treatment effects of MCGP-CS compared with CAU on personal meaning (d = 0.81), goal-orientedness (d = 1.07), positive relations (d = 0.59), purpose in life (d = 0.69); fighting spirit (d = 0.61) (post-intervention) and helpless/hopeless (d = −0.87) (3 months FU); and distress (d = −0.6) and depression (d = −0.38) (6 months FU). Significantly stronger effects of MCGP-CS compared with SGP were found on personal growth (d = 0.57) (3 months FU) and environmental mastery (d = 0.66) (6 months FU).
MCGP-CS is an effective intervention for cancer survivors to improve personal meaning, psychological well-being and mental adjustment to cancer in the short term, and to reduce psychological distress in the long run.
Parasites of the genera Plasmodium and Haemoproteus (Apicomplexa: Haemosporida) are a diverse group of pathogens that infect birds nearly worldwide. Despite their ubiquity, the ecological and evolutionary factors that shape the diversity and distribution of these protozoan parasites among avian communities and geographic regions are poorly understood. Based on a survey throughout the Neotropics of the haemosporidian parasites infecting manakins (Pipridae), a family of Passerine birds endemic to this region, we asked whether host relatedness, ecological similarity and geographic proximity structure parasite turnover between manakin species and local manakin assemblages. We used molecular methods to screen 1343 individuals of 30 manakin species for the presence of parasites. We found no significant correlations between manakin parasite lineage turnover and both manakin species turnover and geographic distance. Climate differences, species turnover in the larger bird community and parasite lineage turnover in non-manakin hosts did not correlate with manakin parasite lineage turnover. We also found no evidence that manakin parasite lineage turnover among host species correlates with range overlap and genetic divergence among hosts. Our analyses indicate that host switching (turnover among host species) and dispersal (turnover among locations) of haemosporidian parasites in manakins are not constrained at this scale.