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Liquid-phase transmission electron microscopy is a technique for simultaneous imaging of the structure and dynamics of specimens in a liquid environment. The conventional sample geometry consists of a liquid layer tightly sandwiched between two Si3N4 windows with a nominal spacing on the order of 0.5 μm. We describe a variation of the conventional approach, wherein the Si3N4 windows are separated by a 10-μm-thick spacer, thus providing room for gas flow inside the liquid specimen enclosure. Adjusting the pressure and flow speed of humid air inside this environmental liquid cell (ELC) creates a stable liquid layer of controllable thickness on the bottom window, thus facilitating high-resolution observations of low mass-thickness contrast objects at low electron doses. We demonstrate controllable liquid thicknesses in the range 160 ± 34 to 340 ± 71 nm resulting in corresponding edge resolutions of 0.8 ± 0.06 to 1.7 ± 0.8 nm as measured for immersed gold nanoparticles. Liquid layer thickness 40 ± 8 nm allowed imaging of low-contrast polystyrene particles. Hydration effects in the ELC have been studied using poly-N-isopropylacrylamide nanogels with a silica core. Therefore, ELC can be a suitable tool for in situ investigations of liquid specimens.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Brain derived neurotrophic factor (BDNF) is the most widely distributed and highly expressed neurotrophin in the CNS. BDNF gene have been associated with increased risk psychiatric disorders. It has been described interaction between BDNF and serotonin system at a neural and genetic level. Neuroticism as a personality trait relevant in borderline personality disorder (BPD) has genetic inheritance and is associated with serotonergic dysfunction. Has been reported that BDNF Val66Met variant is associated with neuroticism in general population. The aim of this study is to test the association between Val66Met and neuroticism and evaluate if the presence of Val66Met allele interacts with polymorphism in promoter region of serotonin transporter gene (5-HTTLPR) for develop neuroticism in BPD. We evaluate personality with NEO PI R in 104 BPD subjects that did not meet criteria for axis I diagnoses and other personality disorders. Genetic analysis of BDNF was performed determining the presence of Val/Val Val/Met and Met/Met BDNF variants. 5-HTTLPR was performed determining the presence of L and S 5-HTTLPR alleles. Statistical analysis were tested with parametric and correlation method with Stata10. We did not found differences in neuroticism between BDNF variants, but when controlled by BDNF alleles we found that Met/Met modulate the expression of 5-HTTLPR, with S-carriers (LS+SS) having higher neuroticism than LL (F = 6.36, p = 0.0031). We found no differences in expression of 5-HTTLPR in other BDNF variants. We conclude that BDNF have a differential modulating effect of 5-HTTLPR in neuroticism in BPD.
Neuroticism is characterized by emotional instability and the tendency to experience negative emotions such as anger, anxiety and depressed mood. Subjects with borderline personality disorder (BPD) present this personality dimension as a temperamental core trait. There has been proposed that neuroticism can appropriately describe the most important characteristics of BPD. The polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) has been implicated in depression, anxiety and suicide. It is estimated that 5-HTTLPR polymorphism account to 7 to 9% of inherited variance of neuroticism in personality. The aim of this study is to evaluate the association between neuroticism and 5-HTTLPR polymorphism in BPD. We evaluate personality with NEO PI R inventory in 104 BPD subjects (76 female/28 male) that did not meet criteria for axis I diagnoses and other personality disorders. The genetic analysis of 5-HTTLPR were performed determining the presence of long and short alleles, subjects were grouped in long/long (LL) and S-carriers (LS+SS). Statistical analysis were tested with parametric and correlation method with Stata10. We found significant difference in neuroticism between the genotype groups (F = 8.57, p = 0.0004) and lower levels of neuroticism in LL than S-carriers. Female have higher neuroticism than male. 5-HTTLPR polymorphism explains 18.02% of inherited variance in neuroticism. The S-carriers had 11.9 times higher risk of presenting elevated neuroticism compared with LL. We conclude that there are relation between 5-HTTLPR polymorphism and neuroticism in BPD. These results should contribute to the genetic study of BPD.
Poly-victims are described as subjects who experience extremely high levels of victimization. This condition is regularly associated with wide psychopathological distress. Children and adolescents are special risk collective for this type of victimization.
To describe and analyze more frequents mental health problems in adolescents with different levels of victimization.
A community sample of 895 adolescents (M = 15.7; SD = 1.3 years old) was subdivided into several groups taking as reference the number of victimizations suffered in the last year, obtained from the Juvenile Victimization Questionnaire. Resulting groups were as follows: those adolescents presenting no type of victimization, the group below average, a group above average and the group of poly-victimized adolescents. Mental health problems were identified with the Youth Self Report, analyzing specifically the DSM syndrome scales.
The group of poly-victimized adolescents presented more significant (p<.05) affective, anxious symptomatology with attention and behavior problems, post-traumatic and obssesive compulsive disturbances, even after Bonferroni's post-hoc contrast regarding the other groups. On the other hand, somatic and oppositional defiant problems were perceived with same intensity between the group above average and the poly-victimized group in front of the groups below victimizations average.
Poly-victimization in adolescents is associated to larger symptomatology patterns and mental health problems development.
Acute respiratory dysfunction is one of the most frequent medical complications of critically ill patients, including those suffering from neurological diseases. It contributes the highest percentage of mortality from non-neurologic causes in neurocritically ill patients [1–3]. This chapter will focus on the mechanisms, diagnostic criteria, stratification of severity, and management of hypoxemia with attention to acute respiratory distress syndrome (ARDS) in the context of the neurocritically ill. Special consideration will be provided as well to other commonly encountered diseases in the intensive care unit (ICU) such as chronic obstructive pulmonary disease (COPD), and venous thromboembolism.
Hookworms of the genus Uncinaria parasitize pinniped pups in various locations worldwide. Four species have been described, two of which parasitize pinniped pups in the southern hemisphere: Uncinaria hamiltoni parasitizes Otaria flavescens and Arctocephalus australis from the South American coast, and Uncinaria sanguinis parasitizes Neophoca cinerea from the Australian coast. However, their geographical ranges and host specificity are unknown. Uncinaria spp. are morphologically similar, but molecular analyses have allowed the recognition of new species in the genus Uncinaria. We used nuclear genetic markers (internal transcribed spacer (ITS) and large subunit (LSU) rDNA) and a mitochondrial genetic marker (cytochrome c oxidase subunit I (COI)) to evaluate the phylogenetic relationships of Uncinaria spp. parasitizing A. australis and O. flavescens from South American coasts (Atlantic and Pacific coasts). We compared our sequences with published Uncinaria sequences. A Generalized Mixed Yule Coalescent (GMYC) analysis was also used to delimit species, and principal component analysis was used to compare morphometry among Uncinaria specimens. Parasites were sampled from A. australis from Peru (12°S), southern Chile (42°S), and the Uruguayan coast, and from O. flavescens from northern Chile (24°S) and the Uruguayan coast. Morphometric differences were observed between Uncinaria specimens from both South American coasts and between Uncinaria specimens from A. australis in Peru and southern Chile. Phylogenetic and GMYC analyses suggest that south-eastern Pacific otariid species harbour U. hamiltoni and an undescribed putative species of Uncinaria. However, more samples from A. australis and O. flavescens are necessary to understand the phylogenetic patterns of Uncinaria spp. across the South Pacific.
Phenological and aerobiological research into major crops is of great value in adapting traditional processes to the new conditions prompted by global climate change. Data on flowering phenology and airborne pollen have also proved useful for harvest forecasting purposes. The current paper reports on an agrometeorological study carried out in the Montilla-Moriles Protected Designation of Origin area (Córdoba, southern Spain) in 2015 and 2016. The study focused on four grape cultivars produced at seven local vineyards (Pedro Ximénez, the most widely grown in the area; Verdejo; Muscat blanc à petits grains; and Chardonnay, which has been recently introduced). Phenological observations were performed on a weekly basis using the Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie scale adapted for grapevine. Airborne pollen concentrations were monitored using one Hirst-type volumetric sampler and seven passive samplers. Airborne pollen was mainly detected in vineyards during inflorescence emergence and flowering. Year-on-year differences in climatic conditions led to differences in airborne pollen levels. The main variables affecting pollen concentrations were dew point and temperature. The life-cycles recorded here were shorter than in temperate climates but longer than in tropical climates. In terms of flowering period, the cultivars studied here were classed as ‘early cultivars’. Data obtained using local passive samplers located directly in the vineyard confirmed that the airborne pollen concentrations recorded by the volumetric sampler were representative of the study area.
Arc welding processes such Gas Tungsten (GTAW), Gas Metal (GMAW) and Submerged Arc (SAW) are typically used in order to produce a weld joint in stainless steels (SS). However, welding thermal cycle generates a sensitization by formation of chromium carbides. In addition, the heat affected zone (HAZ) is also susceptible to sensitization and fracture of the weldment. Weld bead geometric parameters such depth penetration, fusion zone (FZ) width and size of HAZ are mainly determined by welding operation parameters. This research work studies the influence of welding current, welding speed and arc gap on the width and grain size in the HAZ produced by a single pass of autogenous GTAW process applied to a plate butt-welded joint of AISI 304 SS. The welded specimens were prepared for analysis by light optical (LOM) and scanning electron (SEM) microscopies to identify the interfaces between FZ-HAZ and base material as well as the grain growth in the HAZ. Adams equation for 2-D heat distribution was used to estimate theoretically the width of the HAZ. Furthermore, computational simulation which solved a convective-diffusion problem of the volumetric heat applied during the weld pool formation allowed to correlate the thermal gradient and the molten material flow of the FZ with the welding depth penetration, and width and grain size in the HAZ. The results demonstrated that the high heat input generates an important grain growth in the HAZ caused by low heat diffusion in the adjacent material to the fusion line. Welding speed was the main factor in the thermal gradient changes. Simulation results indicate that outward recirculating flow in the molten metal produced by surface tension forces is responsible for the shallow penetration of the autogenous GTAW process. Theoretical and computational estimations of the HAZ are in good agreement with the experimental results.
Energy reserve, estimated as body condition score (BCS), is the major determinant of the re-initiation of ovarian activity in postpartum cows. Leptin, IGF-I and insulin are positively related to BCS and are putative mediators between BCS and reproductive function. However, when BCS and body composition dissociates, concentrations of these metabolic hormones are altered. We hypothesized that increasing lean muscle tissue, but not fat tissue, would diminish the reproductive response to oestrus induction treatments. Thirty lactating beef cows with BCS of 3.10±1.21 and 75.94±12 days postpartum were divided in two groups. Control cows (n=15) were supplemented with 10.20 kg of concentrate daily for 60 days. Treated cows (n=15) were supplemented equally, and received a β-adrenergic receptor agonist (β-AA; 0.15 mg/kg BW) to achieve accretion of lean tissue mass and not fat tissue mass. Twelve days after ending concentrate supplementation/β-AA treatment, cows received a progestin implant to induce oestrus. Cows displaying oestrus were inseminated during the following 60 days, and maintained with a fertile bull for a further 21 days. Cows in both groups gained weight during the supplementation period (Daily weight gain: Control=0.75 kg v. β-AA=0.89 kg). Cows treated with β-AA had a larger increase in BCS (i.e. change in BCS: control=1 point (score 4.13) v. β-AA=2 points (score 5.06; P<0.05), as a result of muscle accretion (i.e. change in muscle depth: control 0.21 cm v. β-AA 0.97 cm; P<0.05) but not adipose tissue (i.e. change in back fat depth; control 0.13 cm v. β-AA −0.06 cm; P<0.05). The changes in body composition in β-AA cows were associated with a reduction in serum concentrations of IGF-I (25.4%) and leptin (27.9%), without observed changes in insulin. Ovulation and pregnancy to 1st service (P>0.05) did not differ between groups. However, the number of cows displaying oestrus (control 13/15 v. β-AA 8/15; P<0.05) and the percentage cycling (control 6/8 v. β-AA 3/10; P=0.07) after progestin treatment and the pregnancy percentage at the end of the breeding period (control 13/15 v. β-AA 8/15; P<0.05) were lower in β-AA than control cows. In summary, the increase BCS through muscle tissue accretion, but not through fat tissue accretion, resulted in a lower response to oestrus induction, lower percentage of cycling animals and lower pregnancy percentage after progestin treatment; which was associated with a decrease in serum concentrations of leptin and IGF-I.
When high strength and high ductility are required, the Twinning Induced Plasticity steels are an excellent choice. Their mechanical advantages are perfectly known in the automotive industry. Then, they are currently deeply studied. During the deformation at high temperature, TWIP steel experiences dynamic recrystallization. This mechanism results from dislocation interactions, and it depends of temperature, stress, strain, and strain rate. Experimental data give the maximum stress reached by the material, but the critical stress which determinates the DRX onset must be calculated from the strain hardening rate. Both stress and strain change simultaneously, and this variation gives the analytic data to determine σc, which is located at the inflection point of θ-σ plot. The main purpose of this paper was to study how the chemical composition and the experimental parameters (temperature and strain rate) affect the DRX, by the calculation and analysis of the σc values. Hot compression tests were applied to a pair of TWIP steels to compare the DRX onset and its relationship with the vanadium addition. The experimental variables were temperature and strain rate. The true stress–true strain plots were used to calculate σc by cutting data up to a previous point before the σp value, then, a polynomial fit and derivation were applied. The Zener-Hollomon parameter (Z) versus the stresses (peak and critical) plots show how the micro-alloying element vanadium improves the strain hardening in the analyzed TWIP steels.