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Although executive and other cognitive deficits have been found in patients with borderline personality disorder (BPD), whether these have brain functional correlates has been little studied. This study aimed to examine patterns of task-related activation and de-activation during the performance of a working memory task in patients with the disorder.
Sixty-seven DSM-IV BPD patients and 67 healthy controls underwent fMRI during the performance of the n-back task. Linear models were used to obtain maps of within-group activations and areas of differential activation between the groups.
On corrected whole-brain analysis, there were no activation differences between the BPD patients and the healthy controls during the main 2-back v. baseline contrast, but reduced activation was seen in the precentral cortex bilaterally and the left inferior parietal cortex in the 2-back v. 1-back contrast. The patients showed failure of de-activation affecting the medial frontal cortex and the precuneus, plus in other areas. The changes did not appear to be attributable to previous history of depression, which was present in nearly half the sample.
In this study, there was some, though limited, evidence for lateral frontal hypoactivation in BPD during the performance of an executive task. BPD also appears to be associated with failure of de-activation in key regions of the default mode network.
To determine if specific dietary patterns are associated with risk of hypertension, type 2 diabetes mellitus (T2DM) and high BMI in four sites in Peru.
We analysed dietary patterns from a cohort of Peruvian adults in four geographical settings using latent class analysis. Associations with prevalence and incidence of hypertension, T2DM and high BMI were assessed using Poisson regression and generalised linear models, adjusted for potential confounders.
Four sites in Peru varying in degree of urbanisation.
Adults aged ≥35 years (n 3280).
We identified four distinct dietary patterns corresponding to different stages of the Peruvian nutrition transition, reflected by the foods frequently consumed in each pattern. Participants consuming the ‘stage 3’ diet, characterised by high proportional consumption of processed foods, animal products and low consumption of vegetables, mostly consumed in the semi-urban setting, showed the highest prevalence of all health outcomes (hypertension 32·1 %; T2DM 10·7 %; high BMI 75·1 %). Those with a more traditional ‘stage 1’ diet characterised by potato and vegetables, mostly consumed in the rural setting, had lower prevalence of hypertension (prevalence ratio; 95 CI: 0·57; 0·43, 0·75), T2DM (0·36; 0·16, 0·86) and high BMI (0·55; 0·48, 0·63) compared with the ‘stage 3’ diet. Incidence of hypertension was highest among individuals consuming the ‘stage 3’ diet (63·75 per 1000 person-years; 95 % CI 52·40, 77·55).
The study found more traditional diets were associated with a lower prevalence of three common chronic diseases, while prevalence of these diseases was higher with a diet high in processed foods and low in vegetables.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Stripe domains in ferroelectric thin films form in order to minimize the total energy of the film. It has been known for some time that a stable configuration is reached when the decrease in elastic energy from domain formation is balanced by the energetic costs of domain wall formation, local elastic strains in the substrate, and internal electric field formation from domain polarizations. The size and strain of each domain is determined by the lattice mismatch and the energetic costs of interface formation. Recent piezoelectric force microscopy measurements have shown that BiFeO3 (BFO) films on SrRuO3/SrTiO3 (001) substrates form striped polarization domains. Since the details of the local structure and polarization cannot be measured at the same time with conventional techniques, we have used synchrotron x-ray microdiffraction to study these effects. Probing only a few domains at a time with the submicron x-ray spot resulted in a diffraction pattern near the substrate (103) reflection consisting of several BFO peaks. We have unambiguously assigned these peaks to individual structural variants. Based on these results, we propose a physical model that includes the striped domains. The structural variants within the stripes are similar to those predicted by striped patterns in rhombohedral films which minimize elastic energy. The local piezoelectric properties were measured using time-resolved microdiffraction in order to examine the role of the striped domains in the linear responses of the film. The out of plane piezoelectric coefficient d33 was approximately 50 pm/V and the piezoelectric strain was proportional to electric field was up to 0.55%, the maximum strain we have measured. The projection of the in-plane piezoelectric coefficients onto the reciprocal space maps for different structural variants had vastly different values due to the differences in orientation of the domains.
To determine the association between excess body fat, assessed by skinfold thickness, and the incidence of type 2 diabetes mellitus (T2DM) and hypertension (HT).
Data from the ongoing PERU MIGRANT Study were analysed. The outcomes were T2DM and HT, and the exposure was skinfold thickness measured in bicipital, tricipital, subscapular and suprailiac areas. The Durnin–Womersley formula and SIRI equation were used for body fat percentage estimation. Risk ratios and population attributable fractions (PAF) were calculated using Poisson regression.
Rural (Ayacucho) and urban shantytown district (San Juan de Miraflores, Lima) in Peru.
Adults (n 988) aged ≥30 years (rural, rural-to-urban migrants, urban) completed the baseline study. A total of 785 and 690 were included in T2DM and HT incidence analysis, respectively.
At baseline, age mean was 48·0 (sd 12·0) years and 47 % were males. For T2DM, in 7·6 (sd 1·3) years, sixty-one new cases were identified, overall incidence of 1·0 (95 % CI 0·8, 1·3) per 100 person-years. Bicipital and subscapular skinfolds were associated with 2·8-fold and 6·4-fold risk of developing T2DM. On the other hand, in 6·5 (sd 2·5) years, overall incidence of HT was 2·6 (95 % CI 2·2, 3·1) per 100 person-years. Subscapular and overall fat obesity were associated with 2·4- and 2·9-fold risk for developing HT. The PAF for subscapular skinfold was 73·6 and 39·2 % for T2DM and HT, respectively.
We found a strong association between subscapular skinfold thickness and developing T2DM and HT. Skinfold assessment can be a laboratory-free strategy to identify high-risk HT and T2DM cases.
Onobrychis viciifolia (sainfoin) is a forage legume crop with many positive agronomic, environmental, nutritional and nutraceutical attributes. Farmers also benefit from its drought tolerance in areas of low rainfall and light free draining soil, mainly due to its deep taproot. It is resistant to most common pest and diseases and is a valuable resource for pollinators, specifically cultivated for honey production in some regions. It has many benefits for animals, being highly palatable and without danger of bloat, which can be life-threatening to livestock. Its decline in Northern Europe started during the Green Revolution and was impacted by changes towards more intensive farming. Unlike other forage legume crops such as red clover and lucerne, sainfoin does not respond well to inputs and is difficult to establish and maintain. Sainfoin could be classified as an ‘orphan crop’ with very little genetic improvement or agronomic studies in the past 60 years. In the past 5–10 years, however, there has been a resurgence in interest and this has given rise to a number of studies and initiation of systematic improvement of the crop, which is indispensable to its reintroduction into the farmed environment. Interest has been driven in part by considerable evidence to suggest that condensed tannins present in the legume foliage, together with other polyphenol compounds, have positive effects on animal nutrition together with anthelmintic properties. These compounds are also thought to play a role in environmental benefits. There remain many challenges to address in order to optimize the potential for cultivation of sainfoin and its use as a beneficial forage crop. This review makes particular reference to a recently completed project; ‘Legume Plus’, funded by the European Union and embracing a multi-disciplinary approach to both understand and improve the crop for farmers. The present review covers results from both this project and other studies during the past 5 years, also drawing on historic studies of etymology, taxonomy, genetics, agronomy and botany, aiming to be a useful resource for research and for practical plant breeders and agronomists.
We discuss the connection between Chevalley’s definition of a covering space and the usual definition given in an introductory topology course. Then we indicate how some theorems about the covering groups of a topological group can be proved from the global point of view, without using local isomorphisms between topological groups.
Let G be a group and H be a subgroup of G. We say that H is left relatively convex in G if the left G-set G/H has at least one G-invariant order; when G is left orderable, this holds if and only if H is convex in G under some left ordering of G. We give a criterion for H to be left relatively convex in G that generalizes a famous theorem of Burns and Hale and has essentially the same proof. We show that all maximal cyclic subgroups are left relatively convex in free groups, in right-angled Artin groups, and in surface groups that are not the Klein-bottle group. The free-group case extends a result of Duncan and Howie. More generally, every maximal m-generated subgroup in a free group is left relatively convex. The same result is valid, with some exceptions, for compact surface groups. Maximal m-generated abelian subgroups in right-angled Artin groups are left relatively convex. If G is left orderable, then each free factor of G is left relatively convex in G. More generally, for any graph of groups, if each edge group is left relatively convex in each of its vertex groups, then each vertex group is left relatively convex in the fundamental group; this generalizes a result of Chiswell.
This is a summary, written by the first-named author, of his joint work with Ross Geoghegan over the past years. Most of the material is available in detail in the preprint “Limit sets for modules over groups on cat(0) spaces – from the Euclidean to the hyperbolic,” available at http://arxiv.org/abs/1306.3403, and I will occasionally refer to specific detail in that paper. Other parts of our joint work - results mostly concerned with extending concepts and results from that paper to higher dimensions – will also be mentioned but are still in preparation.
Let G be a group, and let S be a finite subset of G that generates G as a monoid. The co-word problem is the collection of words in the free monoid S∗ that represent non-trivial elements of G. A current conjecture, based originally on a conjecture of Lehnert and modified into its current form by Bleak, Matucci, and Neunhöffer, says that Thompson’s group V is a universal group with context-free co-word problem. It is thus conjectured that a group has a context-free co-word problem exactly if it is a finitely generated subgroup of V. Hughes introduced the class FSS of groups that are determined by finite similarity structures. An FSS group acts by local similarities on a compact ultrametric space. Thompson’s group V is a representative example, but there are many others.We show that FSS groups have context-free co-word problem under a minimal additional hypothesis. As a result, we can specify a subfamily of FSS groups that are potential counterexamples to the conjecture.
Let G be a finitely generated group, and Σ a finite subset that generates G as a monoid. The word problem of G with respect to Σ consists of all words in the free monoid Σ* that are equal to the identity in G. The co-word problem of G with respect to Σ is the complement in Σ* of the word problem. We say that a group G is coCF if its co-word problem with respect to some (equivalently, any) finite generating set Σ is a context-free language. We describe a generalized Thompson group V(G,θ) for each finite group G and homomorphism θ: G → G. Our group is constructed using the cloning systems introduced by Witzel and Zaremsky. We prove that V(G,θ) is coCF for any homomorphism θ and finite group G by constructing a pushdown automaton and showing that the co-word problem of V(G,θ) is the cyclic shift of the language accepted by our automaton. Demonstrative subgroups of V, introduced by Bleak and Salazar-Diaz, can be used to construct embeddings of certain wreath products and amalgamated free products into V. We extend the class of known finitely generated demonstrative subgroups of V to include all virtually cyclic groups.
An important “stability” theorem in shape theory, due to D. A. Edwards and R. Geoghegan, characterizes those compacta having the same shape as a finite CW complex. In this chapter we present a straightforward and self-contained proof of that theorem.
We give a simple technique to compute the distance between two points in an n-dimensional Euclidean simplex, where the points are given in barycentric coordinates, using only the edge lengths of that simplex. We then use this technique to verify a few computations which will be used in subsequent papers. The most important application is a formula for intrinsically computing the volume of a Euclidean simplex, which is more efficient (and more natural) than any previously documented methods.