321 research outputs found

    Orbital textures and charge density waves in transition metal dichalcogenides

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    Low-dimensional electron systems, as realized naturally in graphene or created artificially at the interfaces of heterostructures, exhibit a variety of fascinating quantum phenomena with great prospects for future applications. Once electrons are confined to low dimensions, they also tend to spontaneously break the symmetry of the underlying nuclear lattice by forming so-called density waves; a state of matter that currently attracts enormous attention because of its relation to various unconventional electronic properties. In this study we reveal a remarkable and surprising feature of charge density waves (CDWs), namely their intimate relation to orbital order. For the prototypical material 1T-TaS2 we not only show that the CDW within the two-dimensional TaS2-layers involves previously unidentified orbital textures of great complexity. We also demonstrate that two metastable stackings of the orbitally ordered layers allow to manipulate salient features of the electronic structure. Indeed, these orbital effects enable to switch the properties of 1T-TaS2 nanostructures from metallic to semiconducting with technologically pertinent gaps of the order of 200 meV. This new type of orbitronics is especially relevant for the ongoing development of novel, miniaturized and ultra-fast devices based on layered transition metal dichalcogenides

    Met vlas naar een biobased economie: omgeving Enschede

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    Al zoekende naar hernieuwbare grondstoffen om producten te ontwikkelen wordt duidelijk dat vlas heel wat potenties biedt. Een aantal partijen in en rondom Enschede is daar alvast van overtuigd en klaar voor de volgende stap: een biobased vlascluster ontwikkelen in omgeving Enschede. Het Ministerie van Economische Zaken is enthousiast over deze ambitie en wil met dit onderzoek de partijen een steun in de rug geven om de volgende stap te maken. Concreet is het onderzoek gericht op de volgende vragen: - Is het mogelijk om een schaalsprong te maken in vlasteelt in omgeving Enschede ten behoeve van de biobased productontwikkeling in de regio? - En zo ja, welke instrumenten kunnen daartoe ingezet worden? Over deze vragen bundelt deze notitie een grote hoeveelheid van beschikbare informatie om de partijen te helpen om tot focus te komen. Ook worden aanbevelingen gemaakt over de route die bewandeld kan worden om de biobased vlascluster te realiseren, zoals welke acties en projecten gerealiseerd moeten worden, alsook welke financieringsinstrumenten beschikbaar zijn om deze acties te realiseren. Ook geven we suggesties over een organisatiestructuur die deze vlascluster kan realiseren

    Dietary Intake of Total, Animal, and Vegetable Protein and Risk of Type 2 Diabetes in the European Prospective Investigation into Cancer and Nutrition (EPIC)-NL Study

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    OBJECTIVE - Dietary recommendations are focused mainly on relative dietary fat and carbohydrate content in relation to diabetes risk. Meanwhile, high-protein diets may contribute to disturbance of glucose metabolism, but evidence from prospective studies is scarce. We examined the association among dietary total, vegetable, and animal protein intake and diabetes incidence and whether consuming 5 energy % from protein at the expense of 5 energy % from either carbohydrates or fat was associated with diabetes risk. RESEARCH DESIGN AND METHODS - A prospective cohort study was conducted among 38,094 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC)-NL study. Dietary protein intake was measured with a validated food frequency questionnaire. Incident diabetes was verified against medical records. RESULTS - During 10 years of follow-up, 918 incident cases of diabetes were documented. Diabetes risk increased with higher total protein (hazard ratio 2.15 [95% CI 1.77-2.60] highest vs. lowest quartile) and animal protein (2.18 [1.80 -2.63]) intake. Adjustment for confounders did not materially change these results. Further adjustment for adiposity measures attenuated the associations. Vegetable protein was not related to diabetes. Consuming 5 energy % from total or animal protein at the expense of 5 energy % from carbohydrates or fat increased diabetes risk. CONCLUSIONS - Diets high in animal protein are associated with an increased diabetes risk. Our findings also suggest a similar association for total protein itself instead of only animal sources. Consumption of energy from protein at the expense of energy from either carbohydrates or fat may similarly increase diabetes risk. This finding indicates that accounting for protein content in dietary recommendations for diabetes prevention may be useful

    Ставлення істориків українських земель другої половини XIX — початку XX ст. до релігії та церкви

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    У статті показані головні підходи істориків того періоду до важливих суспільних явищ, підкреслені відмінності підходи позитивістів та прихильників інших наукових парадигм.The article shows the main approaches of historians of that period to these important social phenomena, stresses the differences between the approaches of the positivists and supporters of other scientific paradigms

    Automatic quantification of perivascular spaces in T2-weighted images at 7 T MRI

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    Perivascular spaces (PVS) are believed to be involved in brain waste disposal. PVS are associated with cerebral small vessel disease. At higher field strengths more PVS can be observed, challenging manual assessment. We developed a method to automatically detect and quantify PVS. A machine learning approach identified PVS in an automatically positioned ROI in the centrum semiovale (CSO), based on -resolution T2-weighted TSE scans. Next, 3D PVS tracking was performed in 50 subjects (mean age 62.9 years (range 27–78), 19 male), and quantitative measures were extracted. Maps of PVS density, length, and tortuosity were created. Manual PVS annotations were available to train and validate the automatic method. Good correlation was found between the automatic and manual PVS count: ICC (absolute/consistency) is 0.64/0.75, and Dice similarity coefficient (DSC) is 0.61. The automatic method counts fewer PVS than the manual count, because it ignores the smallest PVS (length <2 mm). For 20 subjects manual PVS annotations of a second observer were available. Compared with the correlation between the automatic and manual PVS, higher inter-observer ICC was observed (0.85/0.88), but DSC was lower (0.49 in 4 persons). Longer PVS are observed posterior in the CSO compared with anterior in the CSO. Higher PVS tortuosity are observed in the center of the CSO compared with the periphery of the CSO. Our fully automatic method can detect PVS in a 2D slab in the CSO, and extract quantitative PVS parameters by performing 3D tracking. This method enables automated quantitative analysis of PVS

    Exploring Parents' Experiences and Needs During Disclosure of a Cerebral Palsy Diagnosis of Their Young Child: A Scoping Review

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    BACKGROUND: Parents often perceive the news that their child has cerebral palsy (CP) as overwhelming and shocking. They are at increased risk of parental stress and mental health problems, which in turn can affect the interaction between the parent and the child. Parental mental health outcomes are known to be affected by the process of disclosure of a diagnosis. In this study, we aimed to synthesize the current knowledge about parents' experiences and needs regarding communication during the disclosure of the diagnosis of their child with (or at risk of) CP. METHODS: A scoping review following the methodological steps outlined by the Joanna Briggs Institute was performed using PubMed, Embase, CINAHL and PsycINFO. We qualitatively explored parent-reported experiences and needs across included studies, using thematic analysis. RESULTS: A total of 19 studies were included. Six themes were identified, three in relation to experiences (i.e., preceding experiences and feelings, perceptions of the disclosure and emotional impact) and three in relation to needs (i.e., transparency in information, supportive attitude and having a say). Despite high variability across studies regarding parental needs, most studies reported the need for (i) honest and clear information, (ii) good communication skills amongst professionals and (iii) emotional and practical support after diagnosis. CONCLUSIONS: Our findings suggest that parents' experiences and needs in the period when their child's diagnosis of (high risk of) CP is communicated are highly variable, due to an interplay of personal and contextual factors. To facilitate good communication during disclosure, it is crucial that health care professionals assess and understand this complex process and consider parents' needs for open communication and autonomy in the process. Therefore, professionals need to attune to parents' needs and their individual preferences regarding conversations about their child with (or at risk of) CP

    Non-fasting lipids and risk of cardiovascular disease in patients with diabetes mellitus

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    The aim of this study was to examine the effect of postprandial time on the associations and predictive value of non-fasting lipid levels and cardiovascular disease risk in participants with diabetes. This study was conducted among 1,337 participants with diabetes from the Dutch and German (Potsdam) contributions to the European Prospective Investigation into Cancer and Nutrition. At baseline, total cholesterol, LDL- and HDL-cholesterol and triacylglycerol concentrations were measured and the ratio of total cholesterol/HDL-cholesterol was calculated. Participants were followed for incidence of cardiovascular disease. Lipid concentrations changed minimally with increasing postprandial time, except for triacylglycerol which was elevated just after a meal and declined over time (1.86 at 0.1 h to 1.33 at >6 h, p for trend <0.001). During a mean follow-up of 8 years, 116 cardiovascular events were documented. After adjustment for potential confounders, triacylglycerol (HR for third tertile compared with first tertile (HR(t)₃(to)₁), 1.73 [95% CI 1.04, 2.87]), HDL-cholesterol (HR(t)₃(to)₁, 0.41 [95% CI 0.23, 0.72]) and total cholesterol/HDL-cholesterol ratio (HR(t)₃(to)₁, 1.65 [95% CI 0.95, 2.85]) were associated with cardiovascular disease, independent of postprandial time. Cardiovascular disease risk prediction using the UK Prospective Diabetes Study risk engine was not affected by postprandial time. Postprandial time did not affect associations between lipid concentrations and cardiovascular disease risk in patients with diabetes, nor did it influence prediction of cardiovascular disease. Therefore, it may not be necessary to use fasting blood samples to determine lipid concentrations for cardiovascular disease risk prediction in patients with diabete

    Alcoholic beverage preference and diabetes incidence across Europe the Consortium on Health and Ageing Network of Cohorts in Europe and the United States (CHANCES) project

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    It is unknown if wine, beer and spirit intake lead to a similar association with diabetes. We studied the association between alcoholic beverage preference and type 2 diabetes incidence in persons who reported to consume alcohol.Ten European cohort studies from the Consortium on Health and Ageing: Network of Cohorts in Europe and the United States were included, comprising participant data of 62 458 adults who reported alcohol consumption at baseline. Diabetes incidence was based on documented and/or self-reported diagnosis during follow-up. Preference was defined when ⩾70% of total alcohol consumed was either beer, wine or spirits. Adjusted hazard ratios (HRs) were computed using Cox proportional hazard regression. Single-cohort HRs were pooled by random-effects meta-analysis.Beer, wine or spirit preference was not related to diabetes risk compared with having no preference. The pooled HRs were HR 1.06 (95% confidence interval (CI) 0.93, 1.20) for beer, HR 0.99 (95% CI 0.88, 1.11) for wine, and HR 1.19 (95% CI 0.97, 1.46) for spirit preference. Absolute wine intake, adjusted for total alcohol, was associated with a lower diabetes risk: pooled HR per 6 g/day was 0.96 (95% CI 0.93, 0.99). A spirit preference was related to a higher diabetes risk in those with a higher body mass index, in men and women separately, but not after excluding persons with prevalent diseases.This large individual-level meta-analysis among persons who reported alcohol consumption revealed that the preference for beer, wine, and spirits was similarly associated with diabetes incidence compared with having no preference

    Sensory hypersensitivity after acquired brain injury: the patient perspective

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    Purpose: Sensory hypersensitivity is a frequently reported complaint after acquired brain injury (ABI). This study explores patients’ perceptions of sensory hypersensitivity following ABI and its impact on everyday life. Materials and Methods: Semi-structured interviews were conducted with 18 patients with ABI (stroke, brain tumour, TBI) who reported complaints of sensory hypersensitivity. Interview data were analysed using qualitative thematic analysis. Results: Six themes emerged from the data: (1) definition of sensory hypersensitivity, relating to individual perceptions of sensory hypersensitivity; (2) type of sensory stimuli, relating to the variety of stimuli that patients may be sensitive to; (3) course, relating to changes in sensory hypersensitivity following ABI; (4) fatigue, relating to its association with sensory hypersensitivity; (5) consequences of sensory hypersensitivity, relating to the physical, social and emotional impact of sensory hypersensitivity on patients’ lives; and (6) coping strategies, relating to behaviours used to cope with sensory hypersensitivity. Conclusions: Sensory hypersensitivity can have a major impact on patients’ physical well-being, return to work and (social) participation after ABI. Characteristics of sensory hypersensitivity vary between patients with ABI. To develop treatments for sensory hypersensitivity, future studies should focus on cognitive (e.g., filtering information) and psychological factors (e.g., coping) in relation to sensory hypersensitivity

    South African cardiovascular risk stratification guideline for non-cardiac surgery

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    The South African (SA) guidelines for cardiac patients for non-cardiac surgery were developed to address the need for cardiac risk assessment and risk stratification for elective non-cardiac surgical patients in SA, and more broadly in Africa. The guidelines were developed by updating the Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management for Patients Who Undergo Non-cardiac Surgery, with a search of literature from African countries and recent publications. The updated proposed guidelines were then evaluated in a Delphi consensus process by SA anaesthesia and vascular surgical experts. The recommendations in these guidelines are: 1. We suggest that elective non-cardiac surgical patients who are 45 years and older with either a history of coronary artery disease, congestive cardiac failure, stroke or transient ischaemic attack, or vascular surgical patients 18 years or older with peripheral vascular disease require further preoperative risk stratification as their predicted 30-day major adverse cardiac event (MACE) risk exceeds 5% (conditional recommendation: moderate-quality evidence). 2. We do not recommend routine non-invasive testing for cardiovascular risk stratification prior to elective non-cardiac surgery in adults (strong recommendation: low-to-moderate-quality evidence). 3. We recommend that elective non-cardiac surgical patients who are 45 years and older with a history of coronary artery disease, or stroke or transient ischaemic attack, or congestive cardiac failure or vascular surgical patients 18 years or older with peripheral vascular disease should have preoperative natriuretic peptide (NP) screening (strong recommendation: high-quality evidence). 4. We recommend daily postoperative troponin measurements for 48 - 72 hours for non-cardiac surgical patients who are 45 years and older with a history of coronary artery disease, or stroke or transient ischaemic attack, or congestive cardiac failure or vascular surgical patients 18 years or older with peripheral vascular disease, i.e. (i) a baseline risk >5% for MACE 30 days after elective surgery (if no preoperative NP screening), or (ii) an elevated B-type natriuretic peptide (BNP)/N-terminal-prohormone B-type natriuretic peptide (NT-proBNP) measurement before elective surgery (defined as BNP >99 pg/mL or a NT-proBNP >300 pg/mL) (conditional recommendation: moderate-quality evidence). Additional recommendations are given for the management of myocardial injury after non-cardiac surgery (MINS) and medications for comorbidities.The Global Surgery Fellowship grant.http://www.samj.org.zadm2022Anaesthesiolog
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