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The peoples of southern Mesoamerica, including the Classic period Maya, are often claimed to exhibit a distinct type of spatial organization relative to contemporary urban systems. Here, we use the settlement scaling framework and properties of settlements recorded in systematic, full-coverage surveys to examine ways in which southern Mesoamerican settlement systems were both similar to and different from contemporary systems. We find that the population-area relationship in these settlements differs greatly from that reported for other agrarian settlement systems, but that more typical patterns emerge when one considers a site epicenter as the relevant social interaction area, and the population administered from a given center as the relevant interacting population. Our results imply that southern Mesoamerican populations mixed socially at a slower temporal rhythm than is typical of contemporary systems. Residential locations reflected the need to balance energetic and transport costs of farming with lower-frequency costs of commuting to central places. Nevertheless, increasing returns in activities such as civic construction were still realized through lower-frequency social mixing. These findings suggest that the primary difference between low-density urbanism and contemporary urban systems lies in the spatial and temporal rhythms of social mixing.
The fibrous scaffolds for bone tissue engineering that mimic the extracellular matrix with bioactive and bactericidal properties could provide adequate conditions for regeneration of damaged bone. Electrospun ultrathin fiber covered with nano-hydroxyapatite is a favorable fibrous scaffold design. We developed a fast and reproducible strategy to produce polyvinylidene fluoride (PVDF)/nano-hydroxyapatite (nHAp) nanofibrous scaffolds with bactericidal and bioactive properties. Fibrous PVDF scaffolds were obtained first by the electrospinning method. Then, their surfaces were modified using oxygen plasma treatment followed by electrodeposition of nHAp. This process formed nanofibrous and superhydrophilic PVDF fibers (133.6 nm, fiber average diameter) covered with homogeneous nHAp (202.6 nm, average particle diameter) crystals. Energy-dispersive X-ray spectrometry demonstrated the presence of calcium phosphate, indicating a Ca/P molar ratio of approximately 1.64. X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy spectra identified β-phase of nHAp. Thermal analysis indicated a slight reduction in stability after nHAp electrodeposition. Bactericidal assays showed that nHAp exhibited 99.8% efficiency against Pseudomonas aeruginosa bacteria. The PVDF/Plasma and PVDF/nHAp groups had the highest cell viability, total protein, and alkaline phosphatase activity by 7 days after exposure of the scaffolds to MG63 cell culture. Therefore, the developed scaffolds are an exciting alternative for application in bone regeneration.
A functional polymorphism of the brain-derived neurotrophic factor gene (BDNF) Val66Met has been associated with cognitive function and symptom severity in patients with schizophrenia. It has been suggested that the Val66Met polymorphism has a role as a modulator in a range of clinical features of the illness, including symptoms severity, therapeutic responsiveness, age of onset, brain morphology and cognitive function. However, little work has been done in first-episode schizophrenia (FES) spectrum disorders. The objective of this study is to investigate the association of the BDNF Val66Met polymorphism on cognitive function and clinical symptomatology in FES patients.
Using a cross-sectional design in a cohort of 204 patients with FES or a schizophrenia spectrum disorder and 204 healthy matched controls, we performed BDNF Val66Met genotyping and tested its relationship with cognitive testing (attention, working memory, learning/verbal memory and reasoning/problem-solving) and assessment of clinical symptom severity.
There was no significant influence of the BDNF allele frequency on cognitive factor scores in either patients or controls. An augmented severity of negative symptoms was found in FES patients that carried the Met allele.
The results of this study suggest that in patients with a first-episode of schizophrenia or a schizophrenia spectrum disorder, the BDNF Val66Met polymorphism does not exert an influence on cognitive functioning, but is associated with negative symptoms severity. BDNF may serve as suitable marker of negative symptomatology severity in FES patients within the schizophrenia spectrum.
To investigate the association between parity and the risk of incident dementia in women.
We pooled baseline and follow-up data for community-dwelling women aged 60 or older from six population-based, prospective cohort studies from four European and two Asian countries. We investigated the association between parity and incident dementia using Cox proportional hazards regression models adjusted for age, educational level, hypertension, diabetes mellitus and cohort, with additional analysis by dementia subtype (Alzheimer dementia (AD) and non-Alzheimer dementia (NAD)).
Of 9756 women dementia-free at baseline, 7010 completed one or more follow-up assessments. The mean follow-up duration was 5.4 ± 3.1 years and dementia developed in 550 participants. The number of parities was associated with the risk of incident dementia (hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02–1.13). Grand multiparity (five or more parities) increased the risk of dementia by 30% compared to 1–4 parities (HR = 1.30, 95% CI = 1.02–1.67). The risk of NAD increased by 12% for every parity (HR = 1.12, 95% CI = 1.02–1.23) and by 60% for grand multiparity (HR = 1.60, 95% CI = 1.00–2.55), but the risk of AD was not significantly associated with parity.
Grand multiparity is a significant risk factor for dementia in women. This may have particularly important implications for women in low and middle-income countries where the fertility rate and prevalence of grand multiparity are high.
Social cognition has been associated with functional outcome in patients with first episode psychosis (FEP). Social cognition has also been associated with neurocognition and cognitive reserve. Although cognitive reserve, neurocognitive functioning, social cognition, and functional outcome are related, the direction of their associations is not clear. Therefore, the main aim of this study was to analyze the influence of social cognition as a mediator between cognitive reserve and cognitive domains on functioning in FEP both at baseline and at 2 years.
The sample of the study was composed of 282 FEP patients followed up for 2 years. To analyze whether social cognition mediates the influence of cognitive reserve and cognitive domains on functioning, a path analysis was performed. The statistical significance of any mediation effects was evaluated by bootstrap analysis.
At baseline, as neither cognitive reserve nor the cognitive domains studied were related to functioning, the conditions for mediation were not satisfied. Nevertheless, at 2 years of follow-up, social cognition acted as a mediator between cognitive reserve and functioning. Likewise, social cognition was a mediator between verbal memory and functional outcome. The results of the bootstrap analysis confirmed these significant mediations (95% bootstrapped CI (−10.215 to −0.337) and (−4.731 to −0.605) respectively).
Cognitive reserve and neurocognition are related to functioning, and social cognition mediates in this relationship.
Dirofilariosis caused by Dirofilaria immitis (heartworm) is a zoonosis, considered an endemic disease of dogs and cats in several countries of Western Europe, including Portugal. This study assesses the levels of D. immitis exposure in humans from Northern Portugal, to which end, 668 inhabitants of several districts belonging to two different climate areas (Csa: Bragança, Vila Real and Csb: Aveiro, Braga, Porto, Viseu) were tested for anti-D. immitis and anti-Wolbachia surface proteins (WSP) antibodies. The overall prevalence of seropositivity to both anti-D. immitis and WSP antibodies was 6.1%, which demonstrated the risk of infection with D. immitis in humans living in Northern Portugal. This study, carried out in a Western European country, contributes to the characterisation of the risk of infection with D. immitis among human population in this region of the continent. From a One Health point of view, the results of the current work also support the close relationship between dogs and people as a risk factor for human infection
We sought to evaluate the role healthcare providers play in carbapenem-resistant Enterobacteriaceae (CRE) acquisition among hospitalized patients.
A 1:4 case-control study with incidence density sampling.
Academic healthcare center with regular CRE perirectal screening in high-risk units.
We included case patients with ≥1 negative CRE test followed by positive culture with a length of stay (LOS) >9 days. For controls, we included patients with ≥2 negative CRE tests and assignment to the same unit set as case patients with a LOS >9 days.
Controls were time-matched to each case patient. Case exposure was evaluated between days 2 and 9 before positive culture and control evaluation was based on maximizing overlap with the case window. Exposure sources were all CRE-colonized or -infected patients. Nonphysician providers were compared between study patients and sources during their evaluation windows. Dichotomous and continuous exposures were developed from the number of source-shared providers and were used in univariate and multivariate regression.
In total, 121 cases and 484 controls were included. Multivariate analysis showed odds of dichotomous exposure (≥1 source-shared provider) of 2.27 (95% confidence interval [CI], 1.25–4.15; P=.006) for case patients compared to controls. Multivariate continuous exposure showed odds of 1.02 (95% CI, 1.01–1.03; P=.009) for case patients compared to controls.
Patients who acquire CRE during hospitalization are more likely to receive care from a provider caring for a patient with CRE than those patients who do not acquire CRE. These data support the importance of hand hygiene and cohorting measures for CRE patients to reduce transmission risk.
We present quantitative data on population size and plaza area in three groups of ancient Mesoamerican settlements: a sample of 30 Late Postclassic cities and towns from throughout Mesoamerica and two regional settlement systems from the Classic period, including south-central Veracruz (the Mixtequilla) and the Palenque region. Plaza size scales with population in a sublinear relationship in all three groups, meaning that larger settlements had considerably less plaza area per capita than smaller settlements. These results suggest that the currently popular interpretation drawn from Classic Maya archaeology that plazas were places designed to hold the entire urban population for passive viewing of spectacles may be incomplete. We argue that the observed quantitative relationships between population and plaza area support the notion that plazas were designed to be used for a variety of purposes—including several types of ceremonies and marketplaces—held at different times following a regular schedule.
Genetic parameters for visual assessment traits measured at 487 days of age (body structure (BS), finishing precocity (FP) and muscling (MS)), body weight at 450 days of age (W450), age at first calving (AFC), heifer pregnancy (HP) and stayability (STAY, i.e. the probability of a cow to produce at least three calves before reaching 76 months of age) were estimated in Nellore cattle, seeking to include these traits in the selection criteria for dams. The statistical models included additive genetic and residual random effects using single- and two-trait Bayesian analyses. The average heritability estimates were equal to 0·37 for BS, 0·42 for FP, 0·37 for MS and 0·48 for W450. Age at first calving had a low average heritability estimate (0·13), while HP and STAY estimates were higher (0·36 and 0·24, respectively). The genetic correlations between AFC, HP and STAY with visual assessment traits and body weight were favourable, indicating that selecting animals with higher BS, FP, MS and W450 values will result in the indirect selection of animals with lower AFC and successful scores for HP and STAY. The selection of heifers that present an early pregnancy should anticipate AFC and improve HP in the current herd. Except for AFC, the heritability and genetic correlation estimates between the studied traits justify their inclusion in the selection criteria of the Nellore breeding programme.
In a background of interest in staging models in psychiatry, we tested the validity of a simple staging model of cognitive impairment to predict incident dementia.
A large community sample of adults aged ≥55 years (N = 4803) was assessed in the baseline of a longitudinal, four-wave epidemiological enquiry. A two-phase assessment was implemented in each wave, and the instruments used included the Mini-Mental Status Examination (MMSE); the History and Aetiology Schedule and the Geriatric Mental State-AGECAT. For the standardised degree of cognitive impairment Perneczky et al's MMSE criteria were applied. A panel of psychiatrists diagnosed cases of dementia according to DSM-IV criteria, and cases and sub-cases of dementia were excluded for the follow-up waves. Competing risk regression models, adjusted by potential confounders, were used to test the hypothesised association between MMSE levels and dementia risk.
Out of the 4057 participants followed up, 607 (14.9%) were classified as ‘normal’ (no cognitive impairment), 2672 (65.8%) as ‘questionable’ cognitive impairment, 732 (18.0%) had ‘mild’ cognitive impairment, 38 (0.9%) had ‘moderate’ cognitive impairment and eight (0.2%) had ‘severe’ impairment.
Cognitive impairment was associated with risk of dementia, the risk increasing in parallel with the level of impairment (hazard ratio: 2.72, 4.78 and 8.38 in the ‘questionable’, ‘mild’ and ‘moderate’ level of cognitive impairment, respectively).
The documented gradient of increased risk of dementia associated with the severity level of cognitive impairment supports the validity of the simple staging model based on the MMSE assessment.
To (i) explore the factors influencing family out-of-home (OH) eating events and (ii) identify possible opportunities for food businesses to support families in making healthier OH choices.
Focus group discussions were conducted with parents (six to eight participants per group) and friendship pair discussions (informal interviews with two children who are friends) were conducted with children (5–12 years) throughout the island of Ireland. Both discussions were audio-recorded and analysed using a thematic content analysis.
Eight focus groups and sixteen friendship pairs were conducted in Northern Ireland and sixteen focus groups and thirty-two friendship pairs were conducted in the Republic of Ireland.
Purposive sampling was used to recruit a sample of non-related parents and children that represented equal numbers of gender, age, socio-economic status and demographic backgrounds.
The main, overarching theme was that families perceived OH eating to be a treat, while health was not currently a key priority for many parents and children. Children were reported to have most responsibility for their own food choice decisions in this environment, with taste and food neophobia having the greatest influences. Parents believed that if food businesses could meet parent and child priorities in addition to health influences, e.g. change cooking methods, and increase flexibility, then families would be more likely to patronise these establishments.
The entire family OH eating experience needs to be considered when developing public health interventions and this research has highlighted key opportunities that caterers could employ to support healthier family OH food choices.
To test the hypothesis that cognitive impairment in older adults is associated with all-cause mortality risk and the risk increases when the degree of cognitive impairment augments; and then, if this association is confirmed, to report the population-attributable fraction (PAF) of mortality due to cognitive impairment.
A representative random community sample of individuals aged over 55 was interviewed, and 4557 subjects remaining alive at the end of the first year of follow-up were included in the analysis. Instruments used in the assessment included the Mini-Mental Status Examination (MMSE), the History and Aetiology Schedule (HAS) and the Geriatric Mental State (GMS)-AGECAT. For the standardised degree of cognitive impairment Perneczky et al's MMSE criteria were applied. Mortality information was obtained from the official population registry. Multivariate Cox proportional hazard models were used to test the association between MMSE degrees of cognitive impairment and mortality risk. We also estimated the PAF of mortality due to specific MMSE stages.
Cognitive impairment was associated with mortality risk, the risk increasing in parallel with the degree of cognitive impairment (Hazard ratio, HR: 1.18 in the ‘mild’ degree of impairment; HR: 1.29 in the ‘moderate’ degree; and HR: 2.08 in the ‘severe’ degree). The PAF of mortality due to severe cognitive impairment was 3.49%.
A gradient of increased mortality-risk associated with severity of cognitive impairment was observed. The results support the claim that routine assessment of cognitive function in older adults should be considered in clinical practice.
Rocky shore intertidal communities along the cold- and warm-temperate coasts of the south-western Atlantic are dominated by small mussels of the genus Brachidontes s.l. (Mytilidae), yet the status of species occurring in the region remains unresolved. Taxonomic studies have been based on shell morphology, but high phenotypic variability has led to much confusion. Based on mitochondrial and nuclear genes (COI, 28S rDNA and ITS1) from nine localities in Uruguay and Argentina we confirmed the occurrence of three species in the south-western Atlantic: Brachidontes darwinianus and B. rodriguezii in the warm-temperate and B. purpuratus in the cold-temperate sector. The latter two species coexist in the same beds along the transition zone (41–43°S). The phylogeny based on mitochondrial and nuclear genes, indicate an early divergence of B. purpuratus. At the intra-specific level, low genetic differentiation and absence of fossil record for B. purpuratus from the earlier Quaternary marine terraces of Patagonia likely result from a relatively recent (post-LGM) colonization originated from populations in the south-eastern Pacific. In the case of B. rodriguezii, by contrast, genetic intraspecific differentiation, a fossil record of phenotypically-related forms going back to the Late Miocene, and phylogenetic position in the COI-based phylogeny, prompts the hypothesis that this species is derived from a local stock with a long history of occurrence in the warm-temperate region of the south-western Atlantic. While intertidal mussel beds from the south-western Atlantic are ecologically similar in appearance, their assembly involves components clearly differentiated in terms of historical biogeography and phylogeny.
Fish renal morphology has been studied since the 1960’s, but is still incomplete for most species, even for some of the most studied. The functional and morphological diversity and specialization of the fish kidney, due to environmental adaptations, makes this a large subject that remains understudied. References to studies on fish renal structure are given in Table 1. Although authors as Hentschel and Elger contributed to the knowledge of fish renal morphology in a comparative perspective, the knowledge concerning this issue is still reduced. Here we give a short comparative summary of fish renal morphology, using as baseline model the brown trout.
The objective of this study was to estimate (co)variance components using random regression on B-spline functions to weight records obtained from birth to adulthood. A total of 82 064 weight records of 8145 females obtained from the data bank of the Nellore Breeding Program (PMGRN/Nellore Brazil) which started in 1987, were used. The models included direct additive and maternal genetic effects and animal and maternal permanent environmental effects as random. Contemporary group and dam age at calving (linear and quadratic effect) were included as fixed effects, and orthogonal Legendre polynomials of age (cubic regression) were considered as random covariate. The random effects were modeled using B-spline functions considering linear, quadratic and cubic polynomials for each individual segment. Residual variances were grouped in five age classes. Direct additive genetic and animal permanent environmental effects were modeled using up to seven knots (six segments). A single segment with two knots at the end points of the curve was used for the estimation of maternal genetic and maternal permanent environmental effects. A total of 15 models were studied, with the number of parameters ranging from 17 to 81. The models that used B-splines were compared with multi-trait analyses with nine weight traits and to a random regression model that used orthogonal Legendre polynomials. A model fitting quadratic B-splines, with four knots or three segments for direct additive genetic effect and animal permanent environmental effect and two knots for maternal additive genetic effect and maternal permanent environmental effect, was the most appropriate and parsimonious model to describe the covariance structure of the data. Selection for higher weight, such as at young ages, should be performed taking into account an increase in mature cow weight. Particularly, this is important in most of Nellore beef cattle production systems, where the cow herd is maintained on range conditions. There is limited modification of the growth curve of Nellore cattle with respect to the aim of selecting them for rapid growth at young ages while maintaining constant adult weight.
We have discovered eight relatively strong radio sources that have no optical counterparts. A NIR follow-up has detected faint (17–20 mag) host galaxies in all targets. In general, the radio properties are similar to those observed in 3CRR sources but the optical-radio slopes are consistent with moderate to high redshift (z < 4) GHz-peaked spectrum sources. Our results suggest that these are galaxies whose black hole has been recently re-ignited into activity but that retain large-scale radio structures, signatures of previous AGN activity.