Agricultural practices and nitrate pollution in ground water in the Central Valley of Chile

Nitrate contamination of groundwater is an issue of global concern. Anthropogenic fixation of nitrate has increased exponentially in the last century and the over-application of nitrogen fertilizer is currently the largest intrusion into the nitrogen cycle. Previous studies have determined that various regional conditions can contribute to the level of nitrate contamination in groundwater. In addition to chemical and physical conditions, fertilizer application rates and overirrigation can serve as compounding factors. This study attempted to analyze the previously mentioned conditions by monitoring nitrogen concentrations in ground water from sampling wells in the Central Valley of Chile over a 13-month period. Samples were collected monthly and nutrient concentrations were analyzed. In all wells, concentrations of nitrate and nitrite were determined to be well above the established MCL?s for each and a general trend was observed in the concentrations that correlates to seasonal changes in land-use practices. A field experiment was conducted to reduce fertilizer application rates and irrigation water volumes applied to test fields by deploying an experimental fertilizer/ irrigation system. Data from the sampling wells associated with the test fields shows a substantial decrease in nitrate and nitrite concentrations in the groundwater. Furthermore, when the experimental system was combined with improved water delivery methods (medium-volume furrow flooding and low-volume drip irrigation) a decrease in water volumes and fertilizer application rates of up to two? thirds was obtained without affecting crop yield rates. Results of this study suggest that the over-application of fertilizer and irrigation water reported in previous studies are in fact areas of concern and that a link exists between ground water recharge and irrigation volumes. It is further suggested that long-term application of the experimental system is necessary to prove its benefits to the agricultural, ecological, economical, and scientific communities. If the performance record for this device can be repeated under a variety of conditions its role in reducing global intrusions to the nitrogen cycle would be substantial

Molecular basis of flowering under natural long-day conditions in <i>Arabidopsis</i>

Plants sense light and temperature changes to regulate flowering time. Here, we show that expression of the Arabidopsis florigen gene, FLOWERING LOCUS T (FT), peaks in the morning during spring, a different pattern than we observe in the laboratory. Providing our laboratory growth conditions with a red/far-red light ratio similar to open-field conditions and daily temperature oscillation is sufficient to mimic the FT expression and flowering time in natural long days. Under the adjusted growth conditions, key light signalling components, such as phytochrome A and EARLY FLOWERING 3, play important roles in morning FT expression. These conditions stabilize CONSTANS protein, a major FT activator, in the morning, which is probably a critical mechanism for photoperiodic flowering in nature. Refining the parameters of our standard growth conditions to more precisely mimic plant responses in nature can provide a powerful method for improving our understanding of seasonal response

Visual surveys reveal coral growth in mangrove fringe in a subtropical metropolis

Although coexisting mangrove-coral (CMC) habitats have been identified and categorized globally, they are still underreported and understudied. Visual surveys revealed the presence of five species of corals in two out of four potential CMC habitats around Biscayne Bay, Miami, Florida, a highly urbanized subtropical lagoon. These corals were dominated by algal symbionts in the genus Breviolum , suggesting these low-light but thermally variable environments may be buffered from photoinhibition stress that characterizes nearby hardbottom environments. Further surveys and monitoring of CMCs, particularly in urban environments, may inform coastal community ecology and advance conservation and restoration efforts

Distribution of surfactant, lung compliance, and aeration of preterm rabbit lungs after surfactant therapy and conventional and high-frequency oscillatory ventilation

Previous studies in preterm lambs have shown that exogenous surfactant is more uniformly distributed if given at birth before ventilation or if followed by high-frequency ventilation (HFV) after establishing conventional ventilation (CV). We hypothesized that the pre-term rabbit pup would respond similarly and that improved respiratory system compliance (Crs) would accompany improved surfactant distribution. We randomized pups (27 d gestation) into three groups: control, surfactant at birth, and surfactant after 15 min of CV (rescue). We administered dipalmitoylphosphatidyl-[3H]choline-labeled natural surfactant by tracheostomy to each of the treated groups. The two treatment groups were treated for 15 min with either HFV or CV and subsequently with CV. We measured Crs at 15, 25, 35, and 45 min after surfactant. Lungs from pups treated with CV or HFV (n = 89) for 15 min, with and without 30 min of subsequent CV, were cut into 32 pieces that were counted for distribution of label or were sectioned for quantitative morphometry (n = 36). Pups receiving surfactant after 15 min of CV had higher Crs 15 min after surfactant than either pups treated with surfactant at birth or controls (p less than 0.001). The Crs of pups 15 min after rescue surfactant followed by HFV was lower than that of pups treated with CV (p less than 0.05) but was higher than that of either control or pups treated at birth groups (p less than 0.05). Crs at 35 and 45 min after surfactant were the same in all treatment groups. Application of HFV appeared to delay the delivery of surfactant to the distal airspaces.(ABSTRACT TRUNCATED AT 250 WORDS

Standardized outcome measures of mental health in research with older adults who are incarcerated.

PURPOSE: The targeted use of standardized outcome measures (SOMs) of mental health in research with older adults who are incarcerated promotes a common language that enables interdisciplinary dialogue, contributes to the identification of disparities and supports data harmonization and subsequent synthesis. This paper aims to provide researchers with rationale for using "gold-standard" measures used in research with community-dwelling older adults, reporting associated study sample psychometric indexes, and detailing alterations in the approach or measure. DESIGN/METHODOLOGY/APPROACH: The authors highlight the mental health of older adults who are incarcerated. They also discuss the benefits of SOMs in practice and research and then identify gold-standard measures of mental health used in research with community-dwelling older adults and measures used in research with older adults who are incarcerated. Finally, the authors provide several recommendations related to the use of SOMs of mental health in research with this population. FINDINGS: Depression, anxiety and post-traumatic stress disorder are common among older adults who are incarcerated. Researchers have used a variety of measures to capture these mental health problems, some parallel to those used with community-dwelling samples. However, a more targeted use of SOMs of mental health in research with this population will contribute to important strides in this burgeoning field. ORIGINALITY/VALUE: This review offers several practical recommendations related to SOMs of mental health in research with older adults who are incarcerated to contribute to a rigorous evidence base and thus inform practice and potentially improve the health and well-being of this population

Fulfilling the Mission of Academic Medicine: Training Residents in the Health Needs of Prisoners

The single mission of academic medicine is the pursuit of health for all. This mandate serves as a reminder to focus care on vulnerable and underserved populations. The 12 million Americans who cycle through correctional facilities each year are arguably among the most vulnerable populations in this country; predominantly black, with a high burden of disease and many barriers to care after release. Medical training programs should provide exposure to the health needs of prisoners. Residents could establish care with inmates prior to release and arrange follow-up in the community. This addition to training would not only provide care to this underserved group, but also would train residents in the myriad problems prisoners face, and foster social responsibility

Reducing Homicide Risk in Indianapolis between 1997 and 2000

Rates of homicide risk are not evenly distributed across the US population. Prior research indicates that young males in disadvantaged urban neighborhoods are particularly vulnerable to lethal violence. The traditional criminal justice response to violent crime in the urban context has the potential to exacerbate problems, particularly when broad-based arrest sweeps and general deterrence initiatives are the standard models used by law enforcement. Recent studies suggest that alternative intervention approaches that use both specific deterrence combined with improving pro-social opportunities has shown promise in reducing violent crime in these high-risk contexts. This paper examines the changes in homicide patterns for the highest-risk populations in Indianapolis after a “pulling levers” intervention was implemented in the late 1990s to address youth, gang, and gun violence. Multilevel growth curve regression models controlling for a linear trend over time, important structural correlates of homicide across urban neighborhoods, and between-neighborhood variance estimates showed that homicide rates involving the highest-risk populations (i.e., actors 15 to 24 years old) were most likely to experience a statistically significant and substantive reduction after the intervention was implemented (IRR = 0.48, 95% CI = 0.29 – 0.78). Among male actors in this age range, Black male homicide rates (IRR = 0.41, 95% CI = 0.25 – 0.70) and White male rates (IRR = 0.38, 95% CI = 0.15 – 0.79) declined substantially more than homicide rates involving actors outside the 15 to 24 years age range (IRR = 0.95, 95% CI = 0.54 – 1.69). In addition, neighborhoods where specific, community-level strategies were implemented had statistically significant and substantive high-risk homicide rate declines. We conclude that further extension of the pulling levers framework appears warranted in light of the recent findings. Alternative justice strategies that rely on the threat of sanctions coupled with strengthening social service provisions, as well as risk communication aimed at high-risk individuals, appears to hold significant promise as a means to reduce lethal violence