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This study was conducted to assess fruit and seed yield, oil content and oil composition of Jatropha curcas fertilized with different doses of nitrogen and potassium in Espinal (Tolima, Colombia). The yields ranged from 4,570 to 8,800 kg ha-1 of fruits and from 2,430 to 4,746 kg ha-1 of seeds. These yields showed that the fertilizer dose of 150 kg ha-1 N + 120 kg ha-1 K increased fruit production by 92% and seed production by 95%, which represents an increase of about 100% in oil production, which increased from 947 to 1,900 kg ha-1. The total oil content in the seeds ranged from 38.7 to 40.1% (w/w) with a high content of the unsaturated fatty acids oleic (> 47%) and linoleic acid (> 29%). The highest content of oleic acid in the seed oil was from the unfertilized control plants and plants with an application of 100 kg ha-1 of N and 60 kg ha-1 of K, with an average of 48%. The lowest content of oleic acid was registered when a low dose of nitrogen and a high level of potassium were applied at a ratio of 1:2.4 and doses of 50 kg ha-1 N + 120 kg ha-1 K, respectively. Low contents of the saturated fatty acids palmitic (13.4%) and stearic (7.26%) were obtained, making this oil suitable for biodiesel production. The nitrogen was a more important nutrient for the production and quality of oil in J. curcas than potassium under the studied conditions of soil and climate.

The genus Salmonella contains approximately 2,579 serovars, most of which are zoonotic and transmitted by foods of animal origin, such as fresh pork and further processed by-products. Non-typhoid salmonellosis in humans manifests as gastroenteritis, septicemia, or can be asymptomatic during the carrier state. Salmonella spp. has a considerable impact in the pork industry due to economic losses resulting from diagnosis, treatment, reduced production, and because this pathogen constitutes a non-tariff barrier to food trade and a serious public health problem. The microorganism is usually introduced to farms through incoming breeding stock or pig feed and is subsequently spread by sick animals or asymptomatic carriers. Infection and/or dissemination of the microorganism may increase particularly during pre-slaughtering due to contaminated trucks, long periods of time spent in transit, stress during handling and fasting, or high animal density or time spent in corrals. Contamination during slaughtering is commonly associated with carcass de-hairing and polishing, evisceration and rectum separation, or from Salmonella present in skin, oral cavity, feces or lymphatic nodes. Pork contamination may also occur through contact with equipment or tools, handling, storage, or improper preservation during slaughter, post-slaughter, marketing, sale, or consumption. For this reason, Salmonella control, with a focus on the supply chain and risk assessment is fundamental for guaranteeing quality and food safety of pork products in Colombia, thereby contributing to public health and improving competitiveness. Studies directed at establishing baselines for the disease and the microorganism in each of the stages of the supply chain should be conducted, including identification of differential risks and establishing measures for monitoring, prevention and control.

In viticulture, deficit irrigation strategies are often implemented to control vine canopy growth and to impose stress at critical stages of vine growth to improve wine grape quality. To support deficit irrigation scheduling, remote sensing technologies can be employed in the mapping of evapotranspiration (ET) at the field to sub-field scales, quantifying time-varying vineyard water requirements and actual water use. In the current study, we investigate the utility of ET maps derived from thermal infrared satellite imagery over a vineyard in the Central Valley of California equipped with a variable rate drip irrigation (VRDI) system which enables differential water applications at the 30 × 30 m scale. To support irrigation management at that scale, we utilized a thermal-based multi-sensor data fusion approach to generate weekly total actual ET (ETa) estimates at 30 m spatial resolution, coinciding with the resolution of the Landsat reflectance bands. Crop water requirements (ETc) were defined with a vegetative index (VI)-based approach. To test capacity to capture stress signals, the vineyard was sub-divided into four blocks with different irrigation management strategies and goals, inducing varying degrees of stress during the growing season. Results indicate derived weekly total ET from the thermal-based data fusion approach match well with observations. The thermal-based method was also able to capture the spatial heterogeneity in ET over the vineyard due to a water stress event imposed on two of the four vineyard blocks. This transient stress event was not reflected in the VI-based ETc estimate, highlighting the value of thermal band imaging. While the data fusion system provided valuable information, latency in current satellite data availability, particularly from Landsat, impacts operational applications over the course of a growing season.

Brucellosis, also known as “undulant fever” is a zoonotic disease caused by Brucella, which is a facultative intracellular bacterium. Despite efforts to eradicate this disease, infection in uncontrolled domestic animals persists in several countries and therefore transmission to humans is common. Brucella evasion of the innate immune system depends on its ability to evade the mechanisms of intracellular death in phagocytic cells. The BvrR-BvrS two-component system allows the bacterium to detect adverse conditions in the environment. The BvrS protein has been associated with genes of virulence factors, metabolism, and membrane transport. In this study, we predicted the DNA sequence recognized by BvrR with Gibbs Recursive Sampling and identified the three-dimensional structure of BvrR using I-TASSER suite, and the interaction mechanism between BvrR and DNA with Protein-DNA docking and molecular dynamics (MD) simulation. Based on the Gibbs recursive Sampling analysis, we found the motif AAHTGC (H represents A, C, and T nucleotides) as a possible sequence recognized by BvrR. The docking and EMD simulation results showed that C-terminal effector domain of BvrR protein is likely to interact with AAHTGC sequence. In conclusion, we predicted the structure, recognition motif, and interaction of BvrR with DNA.

Reduced water resources are of increasingly urgent global concern. One potential strategy to address the crisis is the use of drought tolerant crops in agriculture. Barley varieties developed for reduced irrigation (“Solum” and “Solar”) use significantly less water than conventional varieties (“Cochise” and “Kopious”). The underlying mechanism of this drought tolerance is unknown but root structure and function play a key role in plant water uptake. In this study, an empirical survey compared early root development between drought tolerant and conventional varieties. Traits associated with root meristem-regulated cell division including rate of seed germination, border cell number and root cap mucilage production, and root hair emergence were quantified during root emergence. Preliminary results revealed that drought tolerant varieties exhibited faster seed germination and root hair production than conventional varieties. Border cell number and mucilage production in the drought tolerant varieties also were higher than in the conventional variety “Kopious,” but lower than in “Cochise”. Each trait, if found to be linked to the observed drought tolerance, could yield a simple, rapid, and inexpensive tool to screen for new crop varieties. Further detailed studies are needed.

An ever-growing challenge to agricultural production worldwide is the reduced availability of water and increased incidence of drought. The development of low-irrigation barley cultivars marks a significant achievement in breeding efforts for drought tolerance, but specific traits conferring adaptation to water stress remain unclear. Here, we report results from two years of replicated field trials comparing yield, phenology, water usage, and rooting characteristics of low-irrigation varieties “Solar” and “Solum” to high-input, semi-dwarf varieties “Kopious” and “Cochise”. The objective was to identify differential performance of varieties under high- and low-water conditions through comparison of growth and developmental traits. Rooting characteristics were analyzed by digging in-field root profile walls to a depth of 1.8 m. Varieties were compared under high (877 mm) and low (223 mm) water regimes including irrigation and precipitation. Observed traits associated with improved performance of the low-irrigation varieties under drought conditions included early vigor, early flowering, greater root growth at 40−80 cm depth, and more effective water use exhibited by greater water extraction post-anthesis. The deeper rooting pattern of the low-irrigation varieties may be related to their ability to use more water post-anthesis under water stress, and thus, to fill grain, compared to high input varieties.

This study uses bibliometric techniques to explore the international knowledge base on climate change education (CCE), which considers education as crucial for addressing the climate emergency through fostering climate-literate citizens. Analyzing two decades of scientific literature on CCE, we identify evolving considerations, foci, trends, and recommendations, examining a total of 1,264 articles published between 2000 and 2022 in educational-related fields in Web of Science. Using bibliometric techniques, we assessed research trends, author co-citations and journal citations to reveal an evolving publication landscape, including shifts in locations of productive researchers, influential articles, and leading journals publishing CCE studies. Bibliometric techniques help to identify the intellectual knowledge structure and inter-journal referencing, encompassing Theoretical Basis of CCE, Psychology of CCE and Communication, Climate Change within Socioscientific Issues, Conceptions of Climate Change, and Epistemology in CCE. Based on the trends, association networks, limitations and gaps revealed by this analysis, we conclude with suggestions for future research.

Objective: This study examined symptoms of anxiety, depression and suicidality in a national sample of college students. Participants: Using national survey data from the Healthy Minds Study (HMS), a random sample from 184 U.S. campuses from fall 2016 to spring 2019 was analyzed (N = 119,875). Methods: Prevalence rates were examined with the Generalized Anxiety Disorder 7-Item scale, Patient Health Questionnaire-9 and suicidality questions. Relationships between anxiety, depression and suicidality were assessed through Spearman's correlations, the Kruskal-Wallis H test and logistic regressions. Results: Findings revealed that screening only for depression would pick up 23% of suicidal ideation, increasing to 35% when also screening for anxiety. Those with anxiety and no to minimal depression had the second highest likelihood of suicide attempt, following those with anxiety and depression. The symptom "feeling afraid something awful might happen" doubled the odds of suicidal ideation. Conclusions: College campuses may benefit from assessing particular anxiety symptoms in relation to suicide.

In the United States, science education has experienced substantial shifts in the last decade. For in-service teachers, professional development programs (PDPs) play an important role in reform success. Despite well-known core features of effective PDPs, research still suggests a range of results among programs that claim to use those features. An analysis of the nuances associated with these core features has emerged as an important step in bridging the gap between conceptual and actual effective PD. This article presents the validation of constructs for "responsive facilitation", which may serve as a source of these nuances. Using an adapted Delphi Method, constructs were validated by multiple expert groups. A 10-construct consensus is presented with an eleventh remaining under dispute. All constructs have connections to current literature and may support the gap noted above. Implications include a structure that may provide nuance to the core features and support more consistently effective PD.