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The Asian monsoon system controls precipitation over mainland Asia and is a critical component of modern global atmospheric circulation (1). During summer monsoons, high insolation over continental regions produces a [...], The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well- dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago.

Studies have shown that factors in the blood of young organisms can rejuvenate the old ones. Studies using heterochronic parabiosis models further reinforced the hypothesis that juvenile factors can rejuvenate aged systems. We sought to determine the effect of juvenile plasma-derived factors on the outcome following hemorrhagic shock injury in aged mice. We discovered that pre-pubertal (young) mice subjected to hemorrhagic shock survived for a prolonged period, in the absence of fluid resuscitation, compared to mature or aged mice. To further understand the mechanism of maturational dependence of injury resolution, extracellular vesicles isolated from the plasma of young mice were administered to aged mice subjected to hemorrhagic shock. The extracellular vesicle treatment prolonged life in the aged mice. The treatment resulted in reduced oxidative stress in the liver and in the circulation, along with an enhanced expression of the nuclear factor erythroid factor 2-related factor 2 (Nrf2) and its target genes, and a reduction in the expression of the transcription factor BTB and CNC homology 1 (Bach1). We propose that plasma factors in the juvenile mice have a reparative effect in the aged mice in injury resolution by modulating the Nrf2/Bach1 axis in the antioxidant response pathway. [ABSTRACT FROM AUTHOR]

An external network for school-based agricultural education (SBAE) teachers is integral to reducing teacher turnover. Because SBAE teachers are often isolated geographically from other teachers, it is important to identify other methods of communication with peers. The California Ag Ed Discussion Lab was acreated in 2016 to more closely address the unique needs of teachers in California. A dearth of literature exists about the use of closed Facebook groups for teachers, especially in agricultural education. The purpose of this study was to analyze posts in a closed Facebook group for SBAE teachers in California to determine the intent and content shared. This study employed quantitative content analysis using a conceptual framework to identify what members were posting about in the California Ag Ed Discussion Lab Facebook group by SBAE teacher role and how they communicated the information via communicative functions of social media. Data collected included three years of posts in the Facebook group. Findings indicated the SBAE teacher roles of Instruction and FFA were the most posted subject areas. Using the conceptual framework, data revealed 53.9% of posts coded to one of three categories: Mobilization/Instruction, Information Sharing/Instruction, and Mobilization/FFA and also coincided with events in the agricultural education teaching profession. [ABSTRACT FROM AUTHOR]

School-based agricultural education (SBAE) and its teachers must remain current with the times to be effective. Producing an abundance of competent, highly qualified, effective, SBAE teachers is an ongoing prerogative, and measuring effective teaching in SBAE is difficult due to the complexity and uniqueness of the demands of the position. The purpose of this study was to identify the self-perceived characteristics of effectiveness of SBAE teachers nationwide. The effective teaching instrument for SBAE teachers (ETI-SBAE), supported by a conceptual framework considering the potential factors impacting the effectiveness of SBAE teachers, was used to determine teacher effectiveness scores in this non-experimental, descriptive survey research study. All SBAE teachers across the country were included in the study's frame. After multiple rounds of data collection, 2807 SBAE teachers responded to the study with complete data sets. It was found that these teachers are diverse and have a variety of needs depending on the state from which they responded and their years of experience. A wide range of personal and professional characteristics were identified. Based on their composite sum effectiveness score, SBAE teachers who intended to remain in the profession through retirement were statistically significantly more effective than those who did not intend to retire or were still undecided. [ABSTRACT FROM AUTHOR]

Among the various chemicals that are commonly used as pesticides, organophosphates (OPs), and to a lesser extent, carbamates, are most frequently associated with adverse long-term neurological consequences. OPs and the carbamate, pyridostigmine, used as a prophylactic drug against potential nerve agent attacks, have also been implicated in Gulf War Illness (GWI), which is often characterized by chronic neurological symptoms. While most OP- and carbamate-based pesticides, and pyridostigmine are relatively potent acetylcholinesterase inhibitors (AChEIs), this toxicological mechanism is inadequate to explain their long-term health effects, especially when no signs of acute cholinergic toxicity are exhibited. Our previous work suggests that a potential mechanism of the long-term neurological deficits associated with OPs is impairment of axonal transport (AXT); however, we had not previously evaluated carbamates for this effect. Here we thus evaluated the carbamate, physostigmine (PHY), a highly potent AChEI, on AXT using an in vitro neuronal live imaging assay that we have previously found to be very sensitive to OP-related deficits in AXT. We first evaluated the OP, diisopropylfluorophosphate (DFP) (concentration range 0.001-10.0 µM) as a reference compound that we found previously to impair AXT and subsequently evaluated PHY (concentration range 0.01-100 nM). As expected, DFP impaired AXT in a concentration-dependent manner, replicating our previously published results. In contrast, none of the concentrations of PHY (including concentrations well above the threshold for impairing AChE) impaired AXT. These data suggest that the long-term neurological deficits associated with some carbamates are not likely due to acute impairments of AXT. [ABSTRACT FROM AUTHOR]

Producing competent, qualified, effective teachers to meet a growing nationwide demand is a daunting task. Identifying and preparing school-based agricultural education teachers is no exception. The purpose of the study was to validate and refine a 58-item effective teaching instrument for SBAE teachers. The population of interest was SBAE teachers nationwide (N = 12,690). Through principal component analysis, 26 of the original 58 items were retained as measures of SBAE teacher effectiveness. The instrument was validated and found to have acceptable Cronbach's alpha levels for each of the six components. As a result, we conclude the instrument is appropriate for measuring the effectiveness of SBAE teachers and recommend it being used with other teachers, especially those in the Career and Technical Education fields. [ABSTRACT FROM AUTHOR]