To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Using validated psychological assessment instruments, this study examined the psychological distress associated with potential language barriers experienced by over 135 000 Puerto Rican residents who either temporarily or permanently migrated to the continental United States with the landfall of Hurricane Maria in 2017.
Participants were Puerto Rican residents (n = 107) who remained in Puerto Rico (control) or left the island for at least 3 months because of Hurricane Maria (migrants). Participants completed an online survey in their preferred language (Spanish or English), which assessed self-reported English language proficiency, Kessler Psychological Distress Scale (K6), Posttraumatic Stress Disorder Checklist for DSM 5, Patient Health Questionnaire 9-item depression scale, and the Generalized Anxiety Disorder 7-item scale. It was hypothesized that migrants with lower self-reported English proficiency would have comparatively higher indices of post-disaster distress than those with a higher proficiency.
Dividing the migrant group by preferred language for questionnaire completion, the Fisher’s exact test showed significant differences in prevalence of severe mental distress, as defined by K6 scores above 13, between the Spanish-preferring migrants (30.4%), English-preferring migrants (0%), and controls (9.6%).
Our results support a possible correlation between decreased language proficiency in post-disaster migrants and a higher risk factor for severe mental distress.
The objective was to compare the performance of the updated Charlson comorbidity index (uCCI) and classical CCI (cCCI) in predicting 30-day mortality in patients with Staphylococcus aureus bacteraemia (SAB). All cases of SAB in patients aged ⩾14 years identified at the Microbiology Unit were included prospectively and followed. Comorbidity was evaluated using the cCCI and uCCI. Relevant variables associated with SAB-related mortality, along with cCCI or uCCI scores, were entered into multivariate logistic regression models. Global model fit, model calibration and predictive validity of each model were evaluated and compared. In total, 257 episodes of SAB in 239 patients were included (mean age 74 years; 65% were male). The mean cCCI and uCCI scores were 3.6 (standard deviation, 2.4) and 2.9 (2.3), respectively; 161 (63%) cases had cCCI score ⩾3 and 89 (35%) cases had uCCI score ⩾4. Sixty-five (25%) patients died within 30 days. The cCCI score was not related to mortality in any model, but uCCI score ⩾4 was an independent factor of 30-day mortality (odds ratio, 1.98; 95% confidence interval, 1.05–3.74). The uCCI is a more up-to-date, refined and parsimonious prognostic mortality score than the cCCI; it may thus serve better than the latter in the identification of patients with SAB with worse prognoses.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Obligate symbionts may be genetically structured among host individuals and among phenotypically distinct host populations. Such processes may in turn determine within-host genetic diversity of symbionts, which is relevant for understanding symbiont population dynamics. We analysed the population genetic structure of two species of feather mites (Proctophyllodes sylviae and Trouessartia bifurcata) in migratory and resident blackcaps Sylvia atricapilla that winter sympatrically. Resident and migratory hosts may provide mites with habitats of different qualities, what might promote specialization of mite populations. We found high genetic diversity of within-host populations for both mite species, but no sign of genetic structure of mites between migratory and resident hosts. Our results suggest that, although dispersal mechanisms between hosts during the non-breeding season are unclear, mite populations are not limited by transmission bottlenecks that would reduce genetic diversity among individuals that share a host. Additionally, there is no evidence that host phenotypic divergence (associated with the evolution of migration and residency) has promoted the evolution of host-specialist mite populations. Unrestricted dispersal among host types may allow symbiotic organisms to avoid inbreeding and to persist in the face of habitat heterogeneity in phenotypically diverse host populations.
This study investigated the potential application of genomic selection under a multi-breed scheme in the Spanish autochthonous beef cattle populations using a simulation study that replicates the structure of linkage disequilibrium obtained from a sample of 25 triplets of sire/dam/offspring per population and using the BovineHD Beadchip. Purebred and combined reference sets were used for the genomic evaluation and several scenarios of different genetic architecture of the trait were investigated. The single-breed evaluations yielded the highest within-breed accuracies. Across breed accuracies were found low but positive on average confirming the genetic connectedness between the populations. If the same genotyping effort is split in several populations, the accuracies were lower when compared with single-breed evaluation, but showed a small advantage over small-sized purebred reference sets over the accuracies of subsequent generations. Besides, the genetic architecture of the trait did not show any relevant effect on the accuracy with the exception of rare variants, which yielded slightly lower results and higher loss of predictive ability over the generations.
Previous cafeteria studies suggested that a moderate natural gastrointestinal nematode (GIN) infection did not modify the resource selection of adult Criollo goats towards tannin-rich plants compared with worm-free goats. A higher infection with Haemonchus contortus could trigger a change in the resource selection behaviour towards tannin-rich foliage. Alternatively, goats might select plant species solely to meet their nutritional requirements. A cafeteria study investigated the effect of a high artificial infection with H. contortus on the feed resource selection of goats. Adult Criollo goats (37.5±4.8 kg BW) with browsing experience were distributed in two groups: the infected group (IG) with six animals artificially infected with H. contortus (6000 L3/animal); and the non-infected group (NIG) with six animals maintained worm-free. The experiment included two 5-day periods with additional 5-day adaptation period. In the first period, animals were offered foliage of five plant species with a decreasing gradient of condensed tannins (CT) (Mimosa bahamensis, Gymnopodium floribundum, Havardia albicans, Acacia pennatula, Lysiloma latisiliqum), and three plant species with negligible CT content (Leucaena leucocephala, Piscidia piscipula and Brosimum alicastrum). In the second period the foliage of B. alicastrum was withdrawn. A grain-based concentrate feed was offered daily at 1% BW in DM basis. Dry matter and nutrient intake was determined. Foliage selection of each experimental group was determined using the Chesson selection index. The H. contortus egg count per gram of faeces (EPG) was determined for infected goats twice daily. Chesson index showed a similar pattern of foliage selection on periods 1 and 2. Mean EPG of goats in IG was 2028±259 EPG during period 1 and 1 293±198 EPG during period 2 (P>0.05). During period 1, the selection pattern was highest for B. alicastrum (tannin-free), followed by a tannin-rich plant (M. bahamensis). These two plants remained as highly selected during period 2. The Chesson index showed that both experimental groups (IG and NIG) selected the same plant species in both periods. Thus, a high H. contortus infection did not affect selection of goats fed with CT-rich plants. Apparently, goats balanced their nutrient intake with the plants selected, showing evidence of nutritional wisdom. This balance may have helped to prevent excess protein in the diet and also to maintain a low GIN infection, both considered as examples of prophylactic self-medication.
The Spanish local beef cattle breeds have most likely common origin followed by a process of differentiation. This particular historical evolution has most probably left detectable signatures in the genome. The objective of this study was to identify genomic regions associated with differentiation processes in seven Spanish autochthonous populations (Asturiana de los Valles (AV), Avileña-Negra Ibérica (ANI), Bruna dels Pirineus (BP), Morucha (Mo), Pirenaica (Pi), Retinta (Re) and Rubia Gallega (RG)). The BovineHD 777K BeadChip was used on 342 individuals (AV, n=50; ANI, n=48; BP, n=50; Mo, n=50; Pi, n=48; Re, n=48; RG, n=48) chosen to be as unrelated as possible. We calculated the fixation index (FST) and performed a Bayesian analysis named SelEstim. The output of both procedures was very similar, although the Bayesian analysis provided a richer inference and allowed us to calculate significance thresholds by generating a pseudo-observed data set from the estimated posterior distributions. We identified a very large number of genomic regions, but when a very restrictive significance threshold was applied these regions were reduced to only 10. Among them, four regions can be highlighted because they comprised a large number of single nucleotide polymorphisms and showed extremely high signals (Kullback–Leiber divergence (KLD)>6). They are located in BTA 2 (5 575 950 to 10 152 228 base pairs (bp)), BTA 5 (17 596 734 to 18 850 702 bp), BTA 6 (37 853 912 to 39 441 548 bp) and BTA 18 (13 345 515 to 15 243 838 bp) and harbor, among others, the MSTN (Myostatin), KIT-LG (KIT Ligand), LAP3 (leucine aminopeptidase 3), NAPCG (non-SMC condensing I complex, subunit G), LCORL (ligand dependent nuclear receptor corepressor-like) and MC1R (Melanocortin 1 receptor) genes. Knowledge on these genomic regions allows to identify potential targets of recent selection and helps to define potential candidate genes associated with traits of interest, such as coat color, muscle development, fertility, growth, carcass and immunological response.
Blazar OJ 287 is one of the best observed extragalactic objects. It's historical light curve goes back to 1890′s. Based on the historical behaviour Sillanpää et al. (1988) showed that OJ 287 displays large periodic outbursts, with a period of 11.7 years. We have monitored OJ 287 intensively for two years, during the OJ-94 project. This project was created for monitoring OJ 287 during its predicted new outburst in 1994. In the data archive we have over 7000 observations on OJ 287, in the radio, infrared and optical bands. This data archive contains the best ever obtained light curves for any extragalactic object. The optical light curve shows continuous variability down to time scales of tens of minutes. The variability observed in OJ 287 can be broken down to (at least) four different categories:
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
The size-dependent optical properties of CdSe nanoparticles are desirable in bio-imaging and cell sorting applications because of their tunable photoluminescence in the visible range. Previous studies have already suggested that CdSe QDs could be utilized for pathogen detection by using suitable capping agents to make it biocompatible; however, systematic works on the effect of crystallite size and composition of the nanocrystals are scarce. The present research will be focused on the effect of CdSe crystal size and composition (pure and doped systems) to systematically evaluate its applicability in detecting pathogens, like Escherichia coli (E. coli). Highly luminescent water-soluble CdSe QDs were firstly synthesized in the aqueous phase, in the presence of thioglycolic acid (TGA) as a capping agent. CdSe/TGA molar ratios, reaction temperature, time, and pH were evaluated in order to optimizer the QDs optical properties. X-Ray diffraction (XRD) measurements confirmed the formation of CdSe exhibiting hexagonal structure with an estimated averaged crystallite size in the 4-6 nm range. Transmission electron microscopy (TEM) analyses evidenced the formation of CdSe nanocrystals with particle sizes between 3-5 nm. UV-Vis measurements showed a strong exciton peak between 390-400 nm with an estimated band gap of 2.64 eV (bulk: 1.74 eV); additionally, a strong fluorescence peak was observed between 500-550 nm using an excitation wavelength of 400 nm. Fourier Transform Infrared Spectroscopy (FT-IR) analyses suggested the actual functionalization of the CdSe surface with TGA functional groups. Preliminary results of the CdSe/TGA coupling with the selected bacteria, E. coli, are presented and discussed.
Predisposition to offspring metabolic dysfunction due to poor maternal nutrition differs with the developmental stage at exposure. Post-weaning nutrition also influences offspring phenotype in either adverse or beneficial ways. We studied a well-established rat maternal protein-restriction model to determine whether post-weaning dietary intervention improves adverse outcomes produced by a deficient maternal nutritional environment in pregnancy. Pregnant rats were fed a controlled diet (C, 20% casein) during pregnancy and lactation (CC) or were fed a restricted diet (R, 10% casein isocaloric diet) during pregnancy and C diet during lactation (RC). After weaning, the offspring were fed the C diet. At postnatal day (PND) 70 (young adulthood), female offspring either continued with the C diet (CCC and RCC) or were fed commercial Chow Purina 5001 (I) to further divide the animals into dietary intervention groups CCI and RCI. Another group of mothers and offspring were fed I throughout (III). Offspring food intake was averaged between PND 95–110 and 235–250 and carcass and liver compositions were measured at PND 25 and 250. Leptin (PND 110 and 250) and serum glucose, triglycerides and cholesterol (PND 250) levels were measured. Statistical analysis was carried out using ANOVA. At PND 25, body and liver weights were similar between groups; however, CCC and RCC carcass protein:fat ratios were lower compared with III diet. At PND 110 and 250, offspring CCC and RCC had higher body weight, food intake and serum leptin compared with CCI and RCI. CCI had lower carcass fat and increased protein compared with CCC and improved fasting glucose and triglycerides. Adult dietary intervention partially overcomes adverse effects of programming. Further studies are needed to determine the mechanisms involved.
A mathematical model is developed to describe deoxidation of water in a physical model of a batch aluminum degassing reactor equipped with the rotor-injector technique, assuming that deoxidation kinetics of water is similar to dehydrogenization of liquid aluminum. Degassing kinetics is described by using mass transport and mass balance principles by assuming that degassing kinetics can be characterized by a mass transfer coefficient, which depends on the process variables. The transport coefficient and the average bubble diameter are estimated with correlations reported in the literature for similar gas-injection systems. The water physical model helped to validate the mathematical model and to perform a process analysis by varying: 1) Gas flow rate (20 and 40 l/min); and 2) Impeller’s angular velocity (290 and 573 rpm). Results from the model agree well with measurements of deoxidation kinetics at low impeller rotating speeds. At high rotating speeds the model is still valid but less reliable because it does not take into account the formation of the vortex at the free surface. Nevertheless, the model provides predictions of the influence of every operating parameter and it can be used as a good approximation for real systems.
In this work the thermal and kinetic analysis of the cooling and solidification of a near eutectic Al-Cu alloy is performed using inverse thermal and solidification kinetics analysis. The Fourier thermal analysis is applied to experimental cooling curves to obtain data on solid fraction evolution and latent heat of solidification. Inverse thermal analysis is applied to calculate the global heat transfer coefficients that allow correct simulation of the cooling of experimental probes. The free growth method is used to obtain the eutectic growth coefficients. All the obtained parameters are feed into a heat transfer-solidification kinetics model to validate the methodology and results generated from this work. It is found a relatively good agreement between experimental and predicted cooling curves which suggest that this methodology could be used to generate useful information needed to simulate eutectic solidification.
A study of the fluid flow in a mixing device proposed to dissolve alloying elements in iron baths is performed through a mathematical model in order to predict the best operating conditions for a proper melting/dissolution of solid alloying particles. The mathematical model consists in the mass and momentum conservation equations (continuity and Turbulent Navier-Stokes equations), and the standard two k-epsilon turbulence model. The model is numerically solved in transient regime with the Volume of Fluid algorithm (VOF) to calculate the vortex shape. VOF is built-in the CFD (Computational Fluid Dynamics) software ANSYS FLUENT 14. A flow of metal enters tangentially in the mixing chamber of the proposed mixing device (taken from an open patent) to generate a vortex. The shape and height of the vortex reached in this chamber depends on several design variables, but in this work only the presence or absence of a barrier in the device is analyzed. Results are obtained on the vortex sizes and shapes, liquid flow patterns, turbulent structure, residence times of the particles of alloying elements added to the melt and mixing times (Residence time distribution curves) of two devices: one with a barrier and the other without this barrier. It is found that the presence of the barrier in the device increases turbulence, destroys the vortex, decreases the residence time of the particles, and decreases the volume of fluid in the device. Most of the features of the barrier are detrimental for mixing and inhibits melting/dissolution of the alloying elements. Then, it is suggested a device without the presence of barrier for better performance.