Agronomic and Economic Performance Characteristics of Conventional and Low-External-Input Cropping Systems in the Central Corn Belt

We conducted a 9-ha field experiment near Boone, IA, to test the hypothesis that yield, weed suppression, and profit characteristics of low-external-input (LEI) cropping systems can match or exceed those of conventional systems. Over a 4-yr period, we compared a conventionally managed 2-yr rotation system {corn (Zea mays L.)/soybean [Glycine max (L.) Merr.]} with two LEI systems: a 3-yr corn/soybean/small grain + red clover (Trifolium pratense L.) rotation, and a 4-yr corn/soybean/small grain + alfalfa (Medicago sativa L.)/alfalfa rotation. Synthetic N fertilizer use was 59 and 74% lower in the 3- and 4-yr systems, respectively, than in the 2-yr system; similarly, herbicide use was reduced 76 and 82% in the 3- and 4-yr systems. Corn and soybean yields were as high or higher in the LEI systems as in the conventional system, and weed biomass in corn and soybean was low (≤4.2 g m−2) in all systems. Experimentally supplemented giant foxtail (Setaria faberi Herrm.) seed densities in the surface 20 cm of soil declined in all systems; supplemented velvetleaf (Abutilon theophrasti Medik.) seed densities declined in the 2- and 4-yr systems and remained unchanged in the 3-yr system. Without subsidy payments, net returns were highest for the 4-yr system ($540 ha−1 yr−1), lowest for the 3-yr system ($475 ha−1 yr−1), and intermediate for the 2-yr system ($504 ha−1 yr−1). With subsidies, differences among systems in net returns were smaller, as subsidies favored the 2-yr system, but rank order of the systems was maintained

Selected sociodemographic factors and related differences in patterns of alcohol use among university students in Slovakia

Background: Alcohol use and misuse and their relation to sociodemograhic factors are well studied among university students in Western European countries and the USA, but less is known about students in Eastern Europe. The historical past as communistic countries might have affected the social life among these populations, which is again one of the main factors determining the alcohol consumption among university students. The aim of our study was to assess the association of selected sociodemographic factors with different patterns of alcohol use among university students in Slovakia. Methods: A sample of 813 young adults (mean age 21.1 years, 63.8% females; response rate of 71%) from four universities in Kosice answered questions about their sociodemographic background and about alcohol use. To obtain a detailed picture of different aspects, alcohol use was measured by four variables: frequency of alcohol use, heavy episodic drinking, frequency of drunkenness and problem drinking. Four separate logistic regression models were used to assess the association between sociodemographic and alcohol-related variables. To assess the potentially different effects in both genders, all two-way interactions with gender were tested. Results: While 41% of the students drank alcohol once a week or more often, 77% reported heavy episodic drinking and 49% had been drunk more than once in the last month. Problem drinking existed in 23.3% of the sample. Gender was consistently associated with all four alcohol-related variables, with males being at higher risk. A higher study year was associated only with lower levels of heavy episodic drinking, but displayed no association with the other studied variables. Living with parents during the semester was consistently associated with less frequent heavy episodic drinking, drunkenness episodes, and problem drinking while having an intimate relationship was associated with less problem drinking only. Conclusions: Our findings for the university students from Slovakia are in line with previous studies in Western Europe. Additionally, it appears that frequent alcohol use, excessive alcohol use (heavy episodic drinking and drunkenness) and problem drinking among university students represent a continuum and are influenced by the same sociodemographic factors

Proceedings of the 3rd Biennial Conference of the Society for Implementation Research Collaboration (SIRC) 2015: advancing efficient methodologies through community partnerships and team science

It is well documented that the majority of adults, children and families in need of evidence-based behavioral health interventionsi do not receive them [1, 2] and that few robust empirically supported methods for implementing evidence-based practices (EBPs) exist. The Society for Implementation Research Collaboration (SIRC) represents a burgeoning effort to advance the innovation and rigor of implementation research and is uniquely focused on bringing together researchers and stakeholders committed to evaluating the implementation of complex evidence-based behavioral health interventions. Through its diverse activities and membership, SIRC aims to foster the promise of implementation research to better serve the behavioral health needs of the population by identifying rigorous, relevant, and efficient strategies that successfully transfer scientific evidence to clinical knowledge for use in real world settings [3]. SIRC began as a National Institute of Mental Health (NIMH)-funded conference series in 2010 (previously titled the “Seattle Implementation Research Conference”; $150,000 USD for 3 conferences in 2011, 2013, and 2015) with the recognition that there were multiple researchers and stakeholdersi working in parallel on innovative implementation science projects in behavioral health, but that formal channels for communicating and collaborating with one another were relatively unavailable. There was a significant need for a forum within which implementation researchers and stakeholders could learn from one another, refine approaches to science and practice, and develop an implementation research agenda using common measures, methods, and research principles to improve both the frequency and quality with which behavioral health treatment implementation is evaluated. SIRC’s membership growth is a testament to this identified need with more than 1000 members from 2011 to the present.ii SIRC’s primary objectives are to: (1) foster communication and collaboration across diverse groups, including implementation researchers, intermediariesi, as well as community stakeholders (SIRC uses the term “EBP champions” for these groups) – and to do so across multiple career levels (e.g., students, early career faculty, established investigators); and (2) enhance and disseminate rigorous measures and methodologies for implementing EBPs and evaluating EBP implementation efforts. These objectives are well aligned with Glasgow and colleagues’ [4] five core tenets deemed critical for advancing implementation science: collaboration, efficiency and speed, rigor and relevance, improved capacity, and cumulative knowledge. SIRC advances these objectives and tenets through in-person conferences, which bring together multidisciplinary implementation researchers and those implementing evidence-based behavioral health interventions in the community to share their work and create professional connections and collaborations

Superoxide Production Increases in Nucleus Tractus Solitarius (NTS) Neurons in Rat Brain Slices during Acute Normobaric Hyperoxia and Hypoxia

We previously reported that hyperbaric hyperoxia stimulates firing rate of putative CO2-chemoreceptors in the solitary complex of the dorsocaudal medulla oblongata in rat brain slices (JAP 95: 910-921, 2003). We next reported that the typical control level of 95%O2 is a greater source of redox stress than ≤ 40%O2 leading to increased cell death in brain slices (J. Neurophysiol. 98:1030-1041, 2007). In the present study we used 20-40%O2 as the control to test the hypothesis that normobaric hyperoxia and hypoxia increase the rate of superoxide production (·O2-) in NTS neurons. Brain slices (400μm, 36-37oC) were maintained using 1- or 2-sided superfusion. Brainstem neurons maintained in 20-40%O2 (5%CO2, balance N2) exhibited i) whole-cell/intracellular activity for many hours, ii) CO2 chemosensitivity (10-15%CO2) and iii) were stimulated by hyperoxia (60-95%O2). ·O2- production was measured (3 min intervals) using the fluorogenic probe, dihydroethidium (2.5μM), continuously loaded via the superfusate. The rate of ·O2- production (slope of fluorescence intensity units/min, FIU/min) increased during acute hyperoxia (20 to 95%O2, 15-20min). Likewise, FIU/min increased during hypoxia (40/20% to 0%O2, 10-20min). ·O2- production during hypoxia was dependent on a lower threshold tissue pO2 that is estimated to be well below 20 Torr based on measurements of tissue slice pO2. ·O2- production during hypoxia was repeatedly induced using 95%N2-5%CO2 during either 1) 1-sided slice superfusion or 2) in combination with an O2-scavenger (1mM Na2SO3) during 2-sided slice superfusion. Myxothiazol (10μM; an inhibitor of Complex III) decreased ·O2- production during hypoxia but had little effect during hyperoxia. This suggests that mitochondrial Complex III is the primary source of ·O2- during hypoxia but not hyperoxia in NTS neurons. Preliminary experiments in CA1 hippocampus and Inferior olive indicate that these neurons do not increase their rate of ·O2- production during hypoxia/Na2SO3. We posit that the similar pattern of ·O2- production in NTS neurons activated by hypoxia and hyperoxia renders these cardio-respiratory neurons vulnerable to redox stimulation and/or stress during sleep disordered breathing (episodic hypoxia, reoxygenation and rebound hyperoxia) and during exposure to normobaric and hyperbaric hyperoxi