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Engineering of materials with specific physical properties has recently focused on the effect of nano-sized ‘guest domains’ in a ‘host matrix’ that enable tuning of electrical, mechanical, photo-optical or thermal properties. A low thermal conductivity is a prerequisite for obtaining effective thermoelectric materials, and the challenge is to limit the conduction of heat by phonons, without simultaneously reducing the charge transport. This is named the ‘phonon glass–electron crystal’ concept and may be realized in host–guest systems. The guest entities are believed to have independent oscillations, so-called rattler modes, which scatter the acoustic phonons and reduce the thermal conductivity. We have investigated the phonon dispersion relation in the phonon glass–electron crystal material Ba 8 Ga 16 Ge 30 using neutron triple-axis spectroscopy. The results disclose unambiguously the theoretically predicted avoided crossing of the rattler modes and the acoustic-phonon branches. The observed phonon lifetimes are longer than expected, and a new explanation for the low κ L is provided. The presence of guest atoms—known as rattlers—in the cages of some clathrate structures is considered to be responsible for the low thermal conductivity of the materials. Neutron spectroscopy provides important evidence regarding the actual phonon dispersion in the material, and the precise way in which this is influenced by rattlers.

The spread of farming from western Asia to Europe had profound long-term social and ecological impacts, but identification of the specific nature of Neolithic land management practices and the dietary contribution of early crops has been problematic. Here, we present previously undescribed stable isotope determinations of charred cereals and pulses from 13 Neolithic sites across Europe (dating ca . 5900–2400 cal B.C.), which show that early farmers used livestock manure and water management to enhance crop yields. Intensive manuring inextricably linked plant cultivation and animal herding and contributed to the remarkable resilience of these combined practices across diverse climatic zones. Critically, our findings suggest that commonly applied paleodietary interpretations of human and herbivore δ ¹⁵N values have systematically underestimated the contribution of crop-derived protein to early farmer diets.

Background Marfan syndrome is associated with morbidity and mortality due to aortic dilatation and dissection. Preventive aortic root replacement has been the standard treatment in Marfan syndrome patients with aortic dilatation. In this study, we present aortic event data from a nationwide Marfan syndrome cohort. Method The nationwide cohort of Danish Marfan syndrome patients was established from the Danish National Patient Registry and the Cause of Death Register, where we retrieved information about aortic surgery and dissections. We associated aortic events with age, sex, and Marfan syndrome diagnosis prior or after the first aortic event. Results From the total cohort of 412 patients, 150 (36.4 %) had an aortic event. Fifty percent were event free at age 49.6. Eighty patients (53.3 %) had prophylactic surgery and seventy patients (46.7 %) a dissection. The yearly event rate was 0.02 events/year/patient in the period 1994–2014. Male patients had a significant higher risk of an aortic event at a younger age with a hazard ratio of 1.75 (CI 1.26–2.42, p  = 0.001) compared with women. Fifty-three patients (12.9 %) were diagnosed with MFS after their first aortic event which primarily was aortic dissection [ n  = 44 (83.0 %)]. Conclusion More than a third of MFS patients experienced an aortic event and male patients had significantly more aortic events than females. More than half of the total number of dissections was in patients undiagnosed with MFS at the time of their event. This emphasizes that diagnosing MFS is lifesaving and improves mortality risk by reducing the risk of aorta dissection.

Background Marfan syndrome is associated with abnormalities in the musculoskeletal system including scoliosis, pectus deformities, protrusio acetabuli, and foot deformities. Over a life span, many patients with Marfan syndrome will need treatment; however, the musculoskeletal morbidity over a life span is not well described. The aim of the present study was to assess the overall burden of musculoskeletal disease in patients with Marfan syndrome. Materials and methods A registry-based, nationwide epidemiological study of patients with a Ghent II verified Marfan syndrome diagnosis from 1977 to 2014. Each patient was matched on age, and sex with up to 100 controls from the background population. Results We identified 407 patients with Marfan syndrome and 40,700 controls and compared their musculoskeletal diagnoses and surgical treatments using Cox proportional hazards ratio (HR). The risk of a registration of a musculoskeletal diagnosis in patients with Marfan syndrome was significantly increased compared to controls (HR: 1.94 (1.69–2.24). One out of six with Marfan syndrome was registered with scoliosis (HR: 36.7 (27.5–48.9). Scoliosis was more common in women with Marfan syndrome compared to men (HR: 4.30 (1.73–1.08)). One out of 11 were registered with a pectus deformity HR: 40.8 (28.1–59.3), and one out of six with a deformity of the foot. Primarily pes planus (HR: 26.0 (15.2–44.3). The proportion of patients with Marfan syndrome (94/407) that underwent musculoskeletal surgery was also significantly higher (HR: 1.76 (1.43–2.16)). The major areas of surgery were the spine, pectups correction, and surgery of the foot/ankle. Ten patients with Marfan syndrome had elective orthopedic surgery without being recognized and diagnosed with Marfan syndrome until later in life. None of these had scoliosis, pectus deformity or a foot deformity. Among patients with an aortic dissection, the age at dissection was 34.3 years in those with at least one major musculoskeletal abnormality. In patients without a major abnormality the age at dissection was 45.1 years ( p  < 0.01). Conclusions The extent of musculoskeletal disease is quite significant in Marfan syndrome, and many will need corrective surgery during their life span. Surgeons should be aware of undiagnosed patients with Marfan syndrome when treating patients with a Marfan syndrome like-phenotype.

Background Women with Turner Syndrome have an increased risk for aortic dissection. Arterial stiffening is a risk factor for aortic dilatation and dissection. Here we investigate if arterial stiffening can be observed in Turner Syndrome patients and is an initial step in the development of aortic dilatation and subsequent dissection. Methods Fifty-seven women with Turner Syndrome (48 years [29–66]) and thirty-six age- and sex-matched controls (49 years [26–68]) were included. Distensibility, blood pressure, carotid-femoral pulse wave velocity (PWV), the augmentation index (Aix) and central blood pressure were determined using cardiovascular magnetic resonance, a 24-h blood pressure measurement and applanation tonometry. Aortic distensibility was determined at three locations: ascending aorta, transverse aortic arch, and descending aorta. Results Mean aortic distensibility in the descending aorta was significantly lower in Turner Syndrome compared to healthy controls ( P  = 0.02), however, this was due to a much lower distensibility among Turner Syndrome with coarctation, while Turner Syndrome without coarctation had similar distensibility as controls. Both the mean heart rate adjusted Aix (31.4% vs. 24.4%; P  = 0.02) and central diastolic blood pressure (78.8 mmHg vs. 73.7 mmHg; P  = 0.02) were higher in Turner Syndrome compared to controls, and these indices correlated significantly with ambulatory night-time diastolic blood pressure. The presence of aortic coarctation ( r  =  −  0.44, P  = 0.005) and a higher central systolic blood pressure ( r  =  −  0.34, P  = 0.03), age and presence of diabetes were inversely correlated with aortic distensibility in TS. Conclusion Aortic wall function in the descending aorta is impaired in Turner Syndrome with lower distensibility among those with coarctation of the aorta, and among all Turner Syndrome higher Aix, and elevated central diastolic blood pressure when compared to sex- and age-matched controls. Trial registration The study was registered at ClinicalTrials.gov ( #NCT01678274 ) on September 3, 2012.

Turner syndrome is a rare condition in women that is associated with either complete or partial loss of one X chromosome, often in mosaic karyotypes. Turner syndrome is associated with short stature, delayed puberty, ovarian dysgenesis, hypergonadotropic hypogonadism, infertility, congenital malformations of the heart, endocrine disorders such as type 1 and type 2 diabetes mellitus, osteoporosis and autoimmune disorders. Morbidity and mortality are increased in women with Turner syndrome compared with the general population and the involvement of multiple organs through all stages of life necessitates a multidisciplinary approach to care. Despite an often conspicuous phenotype, the diagnostic delay can be substantial and the average age at diagnosis is around 15 years of age. However, numerous important clinical advances have been achieved, covering all specialty fields involved in the care of girls and women with Turner syndrome. Here, we present an updated Review of Turner syndrome, covering advances in genetic and genomic mechanisms of disease, associated disorders and multidisciplinary approaches to patient management, including growth hormone therapy and hormone replacement therapy.

Although much has been learned about the design of models of β-sheets during the last decade, modest fold stabilities in water and terminal fraying remain a feature of most β-hairpin peptides. In the case of hairpin capping, nature did not provide guidance for solving the problem. Some observations from prior turn capping designs, with further optimization, have provided a generally applicable, \"unnatural\" beta cap motif (alkanoyl-Trp at the N terminus and Trp-Thr-Gly at the C terminus) that provides a net contribution of 6 + kJ/mol to β-hairpin stability, surpassing all other interactions that stabilize β-hairpins including the covalent disulfide bond. The motif, made up entirely of natural residues, is specific to the termini of antiparallel β-strands and reduces fraying at the ends of hairpins and other β-sheet models. Utilizing this motif, 10- to 22-residue peptide scaffolds of defined stereochemistry that are greater than 98% folded in water have been prepared. The β-cap can also be used to staple together short antiparallel β-strands connected by a long flexible loop.

Neuropeptides exert their activity through binding to G protein-coupled receptors (GPCRs). GPCRs are well-known drug targets in the pharmaceutical industry and are currently discussed as targets to control pest insects. Here, we investigate the neuropeptide adipokinetic hormone (AKH) system of the desert locust . The desert locust is known for its high reproduction, and for forming devastating swarms consisting of billions of individual insects. It is also known that produces three different AKHs as ligands but has only one AKH receptor (AKHR). The AKH system is known to be essential for metabolic regulation, which is necessary for reproduction and flight activity. Nuclear magnetic resonance techniques (NMR) in a dodecylphosphocholin (DPC) micelle solution were used to determine the structure of the three AKHs. The primary sequence of the AKHR was used to construct a 3D molecular model. Next, the three AKHs were individually docked to the receptor, and dynamic simulation of the whole ligand-receptor complex in a model membrane was performed. Although the three endogenous AKHs of have quite different amino acids sequences and chain length (two octa- and one decapeptide), NMR experiments assigned a turn structure in DPC micelle solution for all. The GPCR-ModSim program identified human kappa opioid receptor to be the best template after which the AKHR was modeled. All three AKHs were found to have the same binding site on this receptor, interact with similar residues of the receptor and have comparable binding constants. Molecular switches were also identified; the movement of the receptor could be visually shown when ligands (AKHs) were docked and the receptor was activated. The study proposes a model of binding of the three endogenous ligands to the one existing AKHR in the desert locust and paves the way to use such a model for the design of peptide analogs and finally, peptide mimetics, in the search for novel species-specific insecticides based on receptor-ligand interaction.

Background The risk of aortic dissection is 100-fold increased in Turner syndrome (TS). Unfortunately, risk stratification is inadequate due to a lack of insight into the natural course of the syndrome-associated aortopathy. Therefore, this study aimed to prospectively assess aortic dimensions in TS. Methods Eighty adult TS patients were examined twice with a mean follow-up of 2.4 ± 0.4 years, and 67 healthy age and gender-matched controls were examined once. Aortic dimensions were measured at nine predefined positions using 3D, non-contrast and free-breathing cardiovascular magnetic resonance. Transthoracic echocardiography and 24-hour ambulatory blood pressure were also performed. Results At baseline, aortic diameters (body surface area indexed) were larger at all positions in TS. Aortic dilation was more prevalent at all positions excluding the distal transverse aortic arch. Aortic diameter increased in the aortic sinus, at the sinotubular junction and in the mid-ascending aorta with growth rates of 0.1 - 0.4 mm/year. Aortic diameters at all other positions were unchanged. The bicuspid aortic valve conferred higher aortic sinus growth rates (p < 0.05). No other predictors of aortic growth were identified. Conclusion A general aortopathy is present in TS with enlargement of the ascending aorta, which is accelerated in the presence of a bicuspid aortic valve.

Mineral inclusions are common and have been widely used to investigate complex geological history. When a rock undergoes cooling and decompression after the entrapment of an inclusion into a host mineral, residual pressure may develop within the inclusion because of the differences in thermal expansivity and compressibility between the inclusion and host. By combining laser Raman spectroscopy and experimental data relating hydrostatic pressure and Raman shift, it is possible to estimate the entrapment pressure–temperature (P–T) conditions using an isotropic elastic model. In this study, we report Raman spectroscopic data on both zircon and quartz inclusions in garnet host from the Holsnøy eclogite, Bergen Arcs, Norway. Averaged residual pressures based on different Raman peaks for zircon and quartz inclusions are obtained to be ca. 0.6 GPa and ca. 0.65 GPa respectively. Using the equation of state for zircon and quartz, the entrapment P–T conditions are constrained to be 1.7–1.9 GPa, 680–760 °C, consistent with previous estimates based on phase equilibria. Heating/cooling experiments are performed on an entrapped zircon inclusion. A clear trend is found between the residual zircon inclusion pressure and the externally controlled temperature. We show that the residual zircon inclusion pressure sealed in garnet host is very sensitive to the entrapment temperature, and can be used as a Raman thermometer. The effects of laser heating and the thermo-elastic anisotropy of zircon inclusion are quantified and discussed.