Vocational Training for Disadvantaged Youth in Colombia: A Long-Term Follow-Up

We evaluate the long-term impacts of a randomized Colombian training and job placement program. Following the large short-term effects, we now find that the program effects persist, increasing formal participation and earnings contributions to social security and working in larger firms. By using a large administrative source we are also able to establish that the program improved both male and female labor market outcomes by a similar amount--a result that was not apparent with the smaller evaluation sample. The results point to a cost-effective approach to reducing informality and improving labor market outcomes in the long run

Factors Affecting Consumers’ Purchase Intention of Eco-friendly Food in China: The Evidence from Respondents in Beijing

The purpose aims to examine the key factors influencing Chinese consumer’s purchasing behaviour of eco-friendly food in China giving its context as an emerging economy and its rapidly rising importance in the world eco-friendly food market. This paper adopts and extends the Responsible Environmental Behaviour (REB) theory by empirically testing key psycho-social factors influencing the purchase intention of eco-friendly food and the moderating effects of consumers’ demographic characteristics on the relationship between the key psycho-social factors and the purchase intention.  A number of hypotheses are proposed. A questionnaire was designed and distributed via online survey in Beijing, China.  A total of 239 valid responses were received. The empirical data was used to test the research hypotheses using the hierarchical multiple regression analysis. The research finds that the personality factors in the REB model (i.e., pro-environmental attitudes, the internal locus of control and personal responsibly) have significant positive effects on the consumers’ eco-friendly food purchase intention. Such effect is stable across consumers with different income levels. On the other hand, the knowledge-skill factors in the REB model do not have significant effect on the purchase intention of consumers. This study contributes to a better understanding of factors affecting eco-friendly food consumption intention in China and the behavioural characteristics of consumers in developing countries. Moreover, the findings also shed light on the applicability of the REB theory in emerging economies and a specific industrial context

Electroluminescence on-off ratio control off n−i−n GaAs/AlGaAs-based resonant tunneling structures

We explore the nature of the electroluminescence (EL) emission of purely n-doped GaAs/AlGaAs resonant tunneling diodes (RTDs) and the EL evolution with voltage. A singular feature of such a device is unveiled when the electrical output current changes from higher to lower values and the EL on-off ratio is enhanced by two orders of magnitude compared to the current on-off ratio. By combining the EL and the current properties, we are able to identify two independent impact ionization channels associated with the coherent resonant tunneling current and the incoherent valley current. We also perform the same investigation with an associated series resistance, which induces a bistable electrical output in the system. By simulating a resistance variation for the current voltage and the EL, we are able to tune the EL on-off ratio by up to six orders of magnitude. We further observe that the EL on and off states can be either direct or inverted compared to the tunneling current of the on and off states. This electroluminescence, combined with the unique RTD properties, such as the negative differential resistance and high-frequency operation, enables the development of high-speed functional optoelectronic devices and optical switches.Publisher PDFPeer reviewe

A high-yielding traits experiment for modeling potential production of wheat: field experiments and AgMIP-Wheat multi-model simulations

Grain production must increase by 60% in the next four decades to keep up with the expected population growth and food demand. A significant part of this increase must come from the improvement of staple crop grain yield potential. Crop growth simulation models combined with field experiments and crop physiology are powerful tools to quantify the impact of traits and trait combinations on grain yield potential which helps to guide breeding towards the most effective traits and trait combinations for future wheat crosses. The dataset reported here was created to analyze the value of physiological traits identified by the International Wheat Yield Partnership (IWYP) to improve wheat potential in high-yielding environments. This dataset consists of 11 growing seasons at three high-yielding locations in Buenos Aires (Argentina), Ciudad Obregon (Mexico), and Valdivia (Chile) with the spring wheat cultivar Bacanora and a high-yielding genotype selected from a doubled haploid (DH) population developed from the cross between the Bacanora and Weebil cultivars from the International Maize and Wheat Improvement Center (CIMMYT). This dataset was used in the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Phase 4 to evaluate crop model performance when simulating high-yielding physiological traits and to determine the potential production of wheat using an ensemble of 29 wheat crop models. The field trials were managed for non-stress conditions with full irrigation, fertilizer application, and without biotic stress. Data include local daily weather, soil characteristics and initial soil conditions, cultivar information, and crop measurements (anthesis and maturity dates, total above-ground biomass, final grain yield, yield components, and photosynthetically active radiation interception). Simulations include both daily in-season and end-of-season results for 25 crop variables simulated by 29 wheat crop models

Concurrent Oral 1 - Rheumatoid Arthritis: Treatment [OP4-OP9]: OP4. Inhibition of Radiographic Progression and Improvements in Physical Function at 2 Years, with Increasing Clinical Efficacy Over Time, in Rheumatoid Arthritis (Ra) Patients Treated with Tocilizumab (Tcz): The Lithe Study

Background: Patients with moderate to severe RA who remained on methotrexate (MTX) despite inadequate response were treated with TCZ in a double-blind, randomized, controlled phase 3 trial. Results of a 2-year planned analysis from this study are presented. Methods: Patients were randomized to treatment with TCZ 4 mg/kg + MTX (TCZ4), TCZ 8 mg/kg + MTX (TCZ8) or placebo + MTX (CON) every 4 weeks. If patients failed to respond ( 60% of patients and the DAS28 remission (DAS28 < 2.6) rate was 48% at week 52 and continued to increase to week 104. By week 52, patients treated with TCZ8 had clinically significant improvements in SJC that were maintained through week 104. Rates per 100 PY for adverse events (AEs) were higher in TCZ8 and TCZ4 (263.6, 275.4) vs CON patients (251.4) while rates for serious AEs were comparable (11.4, 12.1, 10.9, respectively). Rates per 100 PY of AEs leading to withdrawal (7.4, 32.5, 4.8) and treatment modification (8.4, 30.7, 20.4) were higher in TCZ8 and TCZ4 vs CON patients, respectively and death rates were comparable (0.6, 0.2, 0.4). Conclusions: Treatment with TCZ + MTX inhibits radiographic progression over 2 years and improves physical function as shown by DAS28 remission, LDAS and low SJC, with a manageable safety profile. Disclosure statement: E.A., F. Hoffmann-La Roche - Employee. P.A., F. Hoffmann-La Roche - Employee. R.B.-V., F. Hoffmann-La Roche - Honoraria. R.F., Genentech - Research Funding, Honoraria. J.K., F. Hoffmann-La Roche - Research funding, Honorari

Analysis of ecological thresholds in a temperate forest undergoing dieback.

Positive feedbacks in drivers of degradation can cause threshold responses in natural ecosystems. Though threshold responses have received much attention in studies of aquatic ecosystems, they have been neglected in terrestrial systems, such as forests, where the long time-scales required for monitoring have impeded research. In this study we explored the role of positive feedbacks in a temperate forest that has been monitored for 50 years and is undergoing dieback, largely as a result of death of the canopy dominant species (Fagus sylvatica, beech). Statistical analyses showed strong non-linear losses in basal area for some plots, while others showed relatively gradual change. Beech seedling density was positively related to canopy openness, but a similar relationship was not observed for saplings, suggesting a feedback whereby mortality in areas with high canopy openness was elevated. We combined this observation with empirical data on size- and growth-mediated mortality of trees to produce an individual-based model of forest dynamics. We used this model to simulate changes in the structure of the forest over 100 years under scenarios with different juvenile and mature mortality probabilities, as well as a positive feedback between seedling and mature tree mortality. This model produced declines in forest basal area when critical juvenile and mature mortality probabilities were exceeded. Feedbacks in juvenile mortality caused a greater reduction in basal area relative to scenarios with no feedback. Non-linear, concave declines of basal area occurred only when mature tree mortality was 3-5 times higher than rates observed in the field. Our results indicate that the longevity of trees may help to buffer forests against environmental change and that the maintenance of old, large trees may aid the resilience of forest stands. In addition, our work suggests that dieback of forests may be avoidable providing pressures on mature and juvenile trees do not pass critical thresholds

Evidence for increasing global wheat yield potential

Wheat is the most widely grown food crop, with 761 Mt produced globally in 2020. To meet the expected grain demand by mid-century, wheat breeding strategies must continue to improve upon yield-advancing physiological traits, regardless of climate change impacts. Here, the best performing doubled haploid (DH) crosses with an increased canopy photosynthesis from wheat field experiments in the literature were extrapolated to the global scale with a multi-model ensemble of process-based wheat crop models to estimate global wheat production. The DH field experiments were also used to determine a quantitative relationship between wheat production and solar radiation to estimate genetic yield potential. The multi-model ensemble projected a global annual wheat production of 1050 +/- 145 Mt due to the improved canopy photosynthesis, a 37% increase, without expanding cropping area. Achieving this genetic yield potential would meet the lower estimate of the projected grain demand in 2050, albeit with considerable challenges

Maternal Colonization With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses.

Background: Maternal rectovaginal colonization with group B Streptococcus (GBS) is the most common pathway for GBS disease in mother, fetus, and newborn. This article, the second in a series estimating the burden of GBS, aims to determine the prevalence and serotype distribution of GBS colonizing pregnant women worldwide. Methods: We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus), organized Chinese language searches, and sought unpublished data from investigator groups. We applied broad inclusion criteria to maximize data inputs, particularly from low- and middle-income contexts, and then applied new meta-analyses to adjust for studies with less-sensitive sampling and laboratory techniques. We undertook meta-analyses to derive pooled estimates of maternal GBS colonization prevalence at national and regional levels. Results: The dataset regarding colonization included 390 articles, 85 countries, and a total of 299924 pregnant women. Our adjusted estimate for maternal GBS colonization worldwide was 18% (95% confidence interval [CI], 17%-19%), with regional variation (11%-35%), and lower prevalence in Southern Asia (12.5% [95% CI, 10%-15%]) and Eastern Asia (11% [95% CI, 10%-12%]). Bacterial serotypes I-V account for 98% of identified colonizing GBS isolates worldwide. Serotype III, associated with invasive disease, accounts for 25% (95% CI, 23%-28%), but is less frequent in some South American and Asian countries. Serotypes VI-IX are more common in Asia. Conclusions: GBS colonizes pregnant women worldwide, but prevalence and serotype distribution vary, even after adjusting for laboratory methods. Lower GBS maternal colonization prevalence, with less serotype III, may help to explain lower GBS disease incidence in regions such as Asia. High prevalence worldwide, and more serotype data, are relevant to prevention efforts

The global abundance of tree palms

Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests