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Green manures are a promising alternative for achieving the sustainable production of maize in the face of low soil fertility and increasingly long canicule periods, particularly in rainfed systems associated with the reproduction of local agrobiodiversity. However, it is necessary to investigate what are the advantages and disadvantages associated with different species of native and exotic pulse, as well as their overall contribution to the sustainable production of maize landraces. In order to do so, we followed the MESMIS method to assess five species of pulse (three native and two exotic) grown with maize in two plots with different soil conditions. This was done in the seasons of 2017 and 2018 the municipality of Villa de Zaachila, Oaxaca, a site with remarkable biological, agricultural and cultural diversity. A fully randomized complete block design was implemented with 11 treatments and three repetitions in the two plots. The output variables of the experiment were: land equivalence ratio, interspecific aggressiveness, content of soil organic matter, decomposition rate, plant survival rate and plant dry biomass. We also evaluated quantitative or qualitative indicators of cost, adaptability and contribution to food security. For all the possible maize-pulse combinations, except for one, polyculture outperformed maize and pulse monocultures. Exotic pulses (Crotalaria junscens spp. and Dolicho lablab) had a better performance in biomass, reincorporation of organic matter and possible nitrogen fixation, as well as greater resistance to drought in the second cycle. The native pulses (Phaseolus vulgaris and Phaseolus coccineus), however, had a greater acceptance and economic output and are important for the food security in our study site. Our results provide quantitative and qualitative elements to design combined schemes of green manures associated with maize that would help tackle current challenges regarding maize productivity, food security and response to climate change.
TwinsMX is a national twin registry in Mexico recently created with institutional support from the Universidad Nacional Autónoma de México. It aims to serve as a platform to advance epidemiological and genetic research in the country and to disentangle the genetic and environmental contributions to health and disease in the admixed Mexican population. Here, we describe our recruitment and data collection strategies and discuss both the progress to date and future directions. More information about the registry is available on our website: https://twinsmxofficial.unam.mx/ (content in Spanish).
This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8–12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.
Cerrado vegetation is the main formation covering c.60% of the land surface of Maranhão, Brazil, with cerradão being the dominant physiognomy. To characterise the cerrado flora in Maranhão, 12 localities were selected across its distribution in the northeastern, central, southern and southeastern regions of the state. A total of 150 angiosperm species were identified, distributed across 105 genera and 43 families. Twelve are new occurrences in Maranhão, and of these, four are also new records for Northeast Brazil. Two distinct floristic regions were recognised: the cerrados of the northeastern and central regions, and the cerrados of the southern region. Three subgroups were recognised in the southern region: cerrados of the highest altitudes, medium-altitude cerrados and cerrados of variable altitudes. Floristic comparisons with the Brazilian cerrados suggest that the medium-altitude southern cerrados of Maranhão are similar to those of the central region of Brazil, whereas the northeastern, central and southern highest-altitude regions form a distinct floristic group.
Speaking fluently requires three main processes to run smoothly: conceptualization, formulation, and articulation. This study investigates to what extent fluency in spontaneous speech in both first (L1) and second (L2) languages can be explained by individual differences in articulatory skills. A group of L2 English learners (n = 51) performed three semispontaneous speaking tasks in their L1 Spanish and in their L2 English. In addition, participants performed articulatory skill tasks that measured the speed at which their articulatory speech plans could be initiated (delayed picture naming) and the rate and accuracy at which their articulatory gestures could be executed (diadochokinetic production). The results showed that fluency in spontaneous L2 speech can be predicted by L1 fluency, replicating earlier studies and showing that L2 fluency measures are, to a large degree, measures of personal speaking style. Articulatory skills were found to contribute modestly to explaining variance in both L1 and L2 fluency.
Traumatic events are associated with increased risk of psychotic experiences, but it is unclear whether this association is explained by mental disorders prior to psychotic experience onset.
To investigate the associations between traumatic events and subsequent psychotic experience onset after adjusting for post-traumatic stress disorder and other mental disorders.
We assessed 29 traumatic event types and psychotic experiences from the World Mental Health surveys and examined the associations of traumatic events with subsequent psychotic experience onset with and without adjustments for mental disorders.
Respondents with any traumatic events had three times the odds of other respondents of subsequently developing psychotic experiences (OR=3.1, 95% CI 2.7–3.7), with variability in strength of association across traumatic event types. These associations persisted after adjustment for mental disorders.
Exposure to traumatic events predicts subsequent onset of psychotic experiences even after adjusting for comorbid mental disorders.
The purpose of the current study was to evaluate the effect of different levels of crude glycerine (CG, 810·9 g glycerol/kg) replacing dry ground maize on intake, digestibility, microbial nitrogen (N) synthesis and N utilization in grazing beef cattle. Five Nellore bulls (332 ± 29·6 kg initial body weight (BW)) were used in a 5 × 5 Latin square design. The animals grazed five Marandu grass (Urochloa brizantha cv. Marandu) paddocks of approximately 0·32 ha. Five supplements were evaluated: mineral supplementation (control, only ad libitum access to a mineral mixture) and 4 g of protein-energy supplementation/kg of BW with four levels of CG (0, 330, 660 and 1000 g/kg) replacing dry ground maize. Bulls that received protein-energy supplementation had greater organic matter (OM) pasture and digested OM (DOM) intakes than the control. No differences were observed among CG levels with regard to OM pasture, neutral detergent fibre and DOM intakes. However, ether extract intake increased linearly as CG levels increased. Protein-energy supplementation enhanced efficiency of microbial N synthesis, N balance and ammonia concentration, but they were not influenced by the CG levels. In conclusion, partial or total replacement of dry ground maize by CG in protein-energy supplements for grazing beef cattle exerted no changes on pasture intake, digestibility and N utilization. Therefore, the use of CG as an energy source in supplements for grazing cattle can be recommended.
Tuberculosis (TB) infection was evaluated in Brazilian immunocompetent children and adolescents exposed and unexposed (control group) to adults with active pulmonary TB. Both groups were analysed by clinical and radiological assessment, TST, QFT-IT and T-SPOT.TB. The three tests were repeated after 8 weeks in the TB-exposed group if results were initially negative. Individuals with latent tuberculosis infection (LTBI) were treated and tests were repeated after treatment. Fifty-nine TB-exposed and 42 controls were evaluated. Rate of infection was 69·5% and 9·5% for the exposed and control groups, respectively. The exposed group infection rate was 61% assessed by TST, 57·6% by T-SPOT.TB, and 59·3%, by QFT-IT. No active TB was diagnosed. Agreement between the three tests was 83·1% and 92·8% in the exposed and control groups, respectively. In the exposed group, T-SPOT.TB added four TB diagnoses [16%, 95% confidence interval (CI) 1·6–30·4] and QFT-IT added three TB diagnoses (12%, 95% CI 0–24·7) in 25 individuals with negative tuberculin skin test (TST). Risk factors associated to TB infection were contact with an adult with active TB [0–60 days: odds ratio (OR) 6·9; >60 days: OR 27·0] and sleeping in the same room as an adult with active TB (OR 5·2). In Brazilian immunocompetent children and adolescents, TST had a similar performance to interferon-gamma release assays and detected a high rate of LTBI.
The Australian Centre for Advanced Photovoltaics (ACAP) co-ordinates the activities of the six Australian research institutions and a group of industrial partners in the Australia-US Institute for Advanced Photovoltaics (AUSIAPV) to develop the next generations of photovoltaic device technology and to provide a pipeline of opportunities for performance increase and cost reduction. AUSIAPV links ACAP with US-based partners. These national and international research collaborations provide a pathway for highly visible, structured photovoltaic research collaboration between Australian and US researchers, institutes and agencies with significant joint programs based on the clear synergies between the participating organizations. The research program is organized in five collaborative Program Packages (PPs). PP1 deals with silicon wafer-based cells, focusing on three main areas: cells from solar grade silicon, rear contact and silicon-based tandem cells. PP2 involves research into a range of organic solar cells, organic/inorganic hybrid cells, "earth abundant" thin-film materials and "third generation" approaches. PP3 is concerned with optics and characterization. PP4 will deliver a substantiated methodology for assessing manufacturing costs of the different technologies and PP5 involves education, training and outreach. The main research topics, results and plans for the future are presented.
The addition of a CdMgTe (CMT) layer at the back of a CdTe solar cell should improve its performance by reflecting both photoelectrons and forward-current electrons away from the rear surface. Higher collection of photoelectrons will increase the cell’s current, and reduction of forward current will increase its voltage. To achieve electron reflection, conformal CMT layers were deposited at the back of CdTe cells, and a variety of measurements including performance curves, transmission electron microscopy, x-ray photoelectron spectroscopy, and energy-dispersive x-ray spectroscopy were performed. Oxidation of magnesium in the CMT layer was addressed by adding a CdTe capping layer. MgCl2 passivation was substituted for CdCl2 in some cases, but little difference was seen.
Hybrid organic/silicon heterostructures have become of great interest for photovoltaic application due to their promising features (e.g. easy fabrication in a low-temperature process) for cost-effective photovoltaics. This work is focused on solar cells with a hybrid heterojunction between the polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) and n-doped monocrystalline silicon. As semi-transparent top contact, a thin (15 nm) Au layer was employed. Devices with different P3HT thicknesses were processed by spin-casting and compared with a reference Au/n-Si Schottky diode solar cell.
The current density-voltage (J-V) measurements of the hybrid devices show a significant increase in open-circuit voltage (VOC) from 0.29 V up to 0.50 V for the best performing hybrid devices compared to the Schottky diode reference, while the short-circuit current density (JSC) does not change significantly. The increased VOC indicates that P3HT effectively reduces the reverse electron current into the gold contact. The wavelength-dependent JSC measurements show a decreased JSC in the wavelength range of P3HT absorption. This is related to the reduced JSC generation in silicon not being compensated by JSC generation in P3HT. It is concluded that the charge generation in P3HT is less efficient than in silicon.
After a thermal annealing of the hybrid P3HT/silicon solar cells, we achieved power conversion efficiencies (PCE) (AM1.5 illumination) up to 6.5% with VOC of 0.52 V, JSC of 18.6 mA/cm² and a fill factor (FF) of 67%. This is more than twice the efficiency of the reference Schottky diode.
Although variation in the long-term course of major depressive disorder (MDD) is not strongly predicted by existing symptom subtype distinctions, recent research suggests that prediction can be improved by using machine learning methods. However, it is not known whether these distinctions can be refined by added information about co-morbid conditions. The current report presents results on this question.
Data came from 8261 respondents with lifetime DSM-IV MDD in the World Health Organization (WHO) World Mental Health (WMH) Surveys. Outcomes included four retrospectively reported measures of persistence/severity of course (years in episode; years in chronic episodes; hospitalization for MDD; disability due to MDD). Machine learning methods (regression tree analysis; lasso, ridge and elastic net penalized regression) followed by k-means cluster analysis were used to augment previously detected subtypes with information about prior co-morbidity to predict these outcomes.
Predicted values were strongly correlated across outcomes. Cluster analysis of predicted values found three clusters with consistently high, intermediate or low values. The high-risk cluster (32.4% of cases) accounted for 56.6–72.9% of high persistence, high chronicity, hospitalization and disability. This high-risk cluster had both higher sensitivity and likelihood ratio positive (LR+; relative proportions of cases in the high-risk cluster versus other clusters having the adverse outcomes) than in a parallel analysis that excluded measures of co-morbidity as predictors.
Although the results using the retrospective data reported here suggest that useful MDD subtyping distinctions can be made with machine learning and clustering across multiple indicators of illness persistence/severity, replication with prospective data is needed to confirm this preliminary conclusion.
We present some highlights of two ongoing investigations that deal with the dynamics of planetary systems. Firstly, until recently, observed eccentric patterns in debris disks were found in young systems. However recent observations of Gyr-old eccentric debris disks leads to question the survival timescale of this type of asymmetry. One such disk was recently observed in the far-IR by the Herschel Space Observatory around ζ2 Reticuli. Secondly, as a binary companion orbits a circumprimary disk, it creates regions where planet formation is strongly handicapped. However, some planets were detected in this zone in tight binary systems (γ Cep, HD 196885). We aim to determine whether a binary companion can affect migration such that planets are brought in these regions and focus in particular on the planetesimal-driven migration mechanism.
PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed 2.5-m optical/infrared telescope to be located at Dome C on the Antarctic plateau. The atmospheric conditions at Dome C deliver a high sensitivity, high photometric precision, wide-field, high spatial resolution, and high-cadence imaging capability to the PILOT telescope. These capabilities enable a unique scientific potential for PILOT, which is addressed in this series of papers. The current paper presents a series of projects dealing with the nearby Universe that have been identified as key science drivers for the PILOT facility. Several projects are proposed that examine stellar populations in nearby galaxies and stellar clusters in order to gain insight into the formation and evolution processes of galaxies and stars. A series of projects will investigate the molecular phase of the Galaxy and explore the ecology of star formation, and investigate the formation processes of stellar and planetary systems. Three projects in the field of exoplanet science are proposed: a search for free-floating low-mass planets and dwarfs, a program of follow-up observations of gravitational microlensing events, and a study of infrared light-curves for previously discovered exoplanets. Three projects are also proposed in the field of planetary and space science: optical and near-infrared studies aimed at characterising planetary atmospheres, a study of coronal mass ejections from the Sun, and a monitoring program searching for small-scale Low Earth Orbit satellite debris items.
PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed 2.5-m optical/infrared telescope to be located at Dome C on the Antarctic plateau. Conditions at Dome C are known to be exceptional for astronomy. The seeing (above ∼30 m height), coherence time, and isoplanatic angle are all twice as good as at typical mid-latitude sites, while the water-vapour column, and the atmosphere and telescope thermal emission are all an order of magnitude better. These conditions enable a unique scientific capability for PILOT, which is addressed in this series of papers. The current paper presents an overview of the optical and instrumentation suite for PILOT and its expected performance, a summary of the key science goals and observational approach for the facility, a discussion of the synergies between the science goals for PILOT and other telescopes, and a discussion of the future of Antarctic astronomy. Paper II and Paper III present details of the science projects divided, respectively, between the distant Universe (i.e. studies of first light, and the assembly and evolution of structure) and the nearby Universe (i.e. studies of Local Group galaxies, the Milky Way, and the Solar System).
Current trends in population aging affect both recipients and providers of informal family caregiving, as the pool of family caregivers is shrinking while demand is increasing. Epidemiological research has not yet examined the implications of these trends for burdens experienced by aging family caregivers.
Cross-sectional community surveys in 20 countries asked 13 892 respondents aged 50+ years about the objective (time, financial) and subjective (distress, embarrassment) burdens they experience in providing care to first-degree relatives with 12 broadly defined serious physical and mental conditions. Differential burden was examined by country income category, kinship status and type of condition.
Among the 26.9–42.5% respondents in high-, upper-middle-, and low-/lower-middle-income countries reporting serious relative health conditions, 35.7–42.5% reported burden. Of those, 25.2–29.0% spent time and 13.5–19.4% money, while 24.4–30.6% felt distress and 6.4–21.7% embarrassment. Mean caregiving hours per week in those giving any time were 16.6–23.6 (169.9–205.8 h/week per 100 people aged 50+ years). Burden in low-/lower-middle-income countries was 2- to 3-fold higher than in higher-income countries, with any financial burden averaging 14.3% of median family income in high-, 17.7% in upper-middle-, and 39.8% in low-/lower-middle-income countries. Higher burden was reported by women than men and for conditions of spouses and children than parents or siblings.
Uncompensated family caregiving is an important societal asset that offsets rising formal healthcare costs. However, the substantial burdens experienced by aging caregivers across multiple family health conditions and geographic regions threaten the continued integrity of their caregiving capacity. Initiatives supporting older family caregivers are consequently needed, especially in low-/lower-middle-income countries.
A life-course approach to reduction of risk of non-communicable diseases (NCD) suggests that early-life interventions may be more effective than lifestyle modifications in middle age. Knowledge translation to develop understanding of the Developmental Origins of Health and Disease (DOHaD) within the community offers the potential to encourage informed diet and lifestyle choices supporting reduction of NCD risk in current and future generations. Many women do not make sustained dietary change before or during pregnancy, therefore appropriate nutritional behaviours need to be established prior to adulthood. This makes adolescence an appropriate stage for interventions to establish suitable dietary and lifestyle behaviours. Therefore, we engaged adolescents in a school-based educational intervention, and assessed the value of this in development of understanding of DOHaD concepts to support behaviour change that could lead to NCD risk reduction in the next generation. Modules of course work were written for 11–14 year olds and trialled in nine schools. Matched pre- and post-intervention questionnaire responses from 238 students and 99 parents, and post-intervention interviews evaluated the intervention. Understanding of a link between maternal diet during pregnancy and the health of the foetus in adulthood increased from 46% to 76% following intervention. Post-intervention evidence suggests the programme facilitated discussion of diet, lifestyle and DOHaD concepts in most families. The intervention was effective in improving understanding of DOHaD concepts and in some cases led to appropriate behaviour change. However, the sustainability of these changes remains to be determined through on-going evaluation of attitudes and behaviour within this cohort.
In a recent study by our group on the prevalence of intestinal parasitic infections and on the knowledge, attitudes and practices of local residents of Campos dos Goytacazes, Rio de Janeiro, Brazil, we observed that about 50% of the inhabitants were parasitized and had some knowledge of intestinal parasitic infections but did not apply this knowledge in daily practice. We were thus motivated to implement strategies in health education to promote preventive measures in the locality. The goal of the present work was to evaluate the influence of health education on the prevalence of intestinal parasitic infections in the region in an effort to strengthen public policies for controlling these diseases in Brazil. The methodology adopted was based on action-research and a theoretical framework of health promotion. Our results demonstrate that the study population exhibited an enhanced awareness of the importance of disease from intestinal parasitic infections. Attitudes and practices related to prevention were significantly improved after the shared health education. In conclusion, this study allowed the shared construction of knowledge that reflected the true needs of the residents.