Sites In Southwest Research Articles

Factors Associated With 30-Day Readmissions After Transsphenoidal Pituitary Surgery

PurposeDetermine the association between clinical and demographic factors and 30-day readmission risk after pituitary surgery. MethodsPatients undergoing pituitary surgery between January 2018 and December 2022 were retrospectively reviewed. Cases were extracted from a converged electronic health record that included surgeries performed at the Midwest, Southeast, and Southwest campuses of the same healthcare Enterprise. Variables were compared between patients with 30-day readmission following discharge after pituitary surgery (N = 83) and a randomly sampled patient cohort with pituitary surgery but no readmission within 30 days (N = 174). ResultsIn a multivariable regression model looking at the relationship between patient characteristics and readmission risk, every increase in the Medicare Severity Diagnosis Related Group score resulted in a nearly 2.3-fold increase in the risk of readmission (OR = 2.335, 95% CI 1.050, 5.562, P = .045). The presence of arginine vasopressin deficiency increased the odds of readmission by more than 2-fold (OR = 2.784, 95% CI 1.118, 7.124, P = .029). The Midwest site was observed to have a nearly 67% decrease in readmission risk compared to the Southwest site (OR = 0.334, 95% CI 0.134, 0.813, P = .016), with the Southeast site being comparable to the Southwest. ConclusionOur study identifies postoperative arginine vasopressin deficiency, greater co-morbidities, and geographic location as risk factors for 30-day readmission after pituitary surgery. Further investigation is required to determine how site-specific care processes can be adopted to lower readmission risk at other locations in the same healthcare enterprise.

Microplastics in the Surface Waters and Sediment in an Agrarian Part of Vembanad-Kol Wetlands, the Largest Ramsar Site—Southwest India

Microplastics in the Surface Waters and Sediment in an Agrarian Part of Vembanad-Kol Wetlands, the Largest Ramsar Site—Southwest India

Geochemical Evolution in Historical Time of Thermal Mineral Springs at Campetti Southwest (Veii, Central Italy) through Geoarcheological Investigation

A multidisciplinary study, involving hydrogeological, geochemical, and mineralogical analyses, was conducted to define the evolution of thermal mineral springs in the Sabatini Volcanic District (SVD) (Central Italy) in a historic period. The outcomes were integrated with the archeological findings to improve the knowledge of the evolution of Veii, a settlement established since the Iron Age and later expanded by Etruscans and Romans. During the archeological excavations, water-related buildings were identified, especially at the Campetti Southwest site in the Veii settlement. Votive inscriptions also suggest the presence of buildings linked to sacred waters, even if a clear definition of the source and type of water is missing. In the SVD, some low-flow thermal mineral springs are present as a result of the mixing of thermal and CO2-rich groundwater from the deep carbonate aquifer and the cold, shallow volcanic aquifer. Mineralogical and chemical analyses characterized the travertine and Fe-hydroxide deposits on Roman tanks and walls in Campetti Southwest and in a nearby ancient Roman bath along the Valchetta River. These deposits showed different relative concentrations of sedimentary and volcanic-related elements, testifying a geochemical evolution of the groundwater mixing and the presence of a paleothermal mineral spring in Campetti Southwest.

Impact of repeated mass ivermectin administration using a community directed approach on L. loa infection in Chrysops silacea of the rain forest and forest savanna of Cameroon

BackgroundLoiasis is an endemic filarial infection in the rainforest zone of West and Central Africa. Repeated annual community-directed treatment with ivermectin (CDTI) delivered for several years to control onchocerciasis has been shown to reduce the prevalence and intensity of Loiasis in some Loa loa-Onchocerca volvulus co-endemic areas. However, the impact of these multiple rounds of CDTI on entomological indicators of loiasis transmission is not known, and was therefore assessed in this study in areas with contrasting histories of CDTI. MethodsThe study was conducted in the East, North-west and South-west 1 CDTI project sites of Cameroon. Two communities per CDTI project were selected for fly collection and dissection. Ivermectin treatment coverage was documented in these areas, and this was correlated to Chrysops infection and infective rates. A total of 7029 female Chrysops were collected from 6 communities of the 3 CDTI projects (East, North-west, and South-west 1) and from 2 communities in a non-CDTI district (East). ResultsChrysops biting densities and parous rates were significantly reduced in the North-west and South-west sites post-CDTI, while in the East, biting densities were similar in non-CDTI and CDTI sites, with higher parous rates observed in the non-CDTI site. Infection and infective rates in the East non-CDTI site were 4.4% and 1.8% respectively, as compared to 3.3% and 1.3% in the CDTI site after 10 ivermectin rounds (there were no baseline data for the latter). In the North-west site, significant reductions in Chrysops infection and infective rates from 10.2% and 4.2% respectively, to 3.5% and 1.2 (after 9 rounds of ivermectin treatment), were recorded following CDTI. In the South-west, infection rate significantly increased from 1.74% to 2.8% and infective rate remained statistically unchanged after 14 rounds of CDTI (0.45% - 0.40%). Similar trends in Mean Head L3 were observed except in the East site where this indicator was similar in both CDTI and control sites. Only in the North-west site did monthly transmission potentials decrease significantly. ConclusionThis study demonstrated that the impact of repeated annual treatment with ivermectin for the control of onchocerciasis using community directed delivery approach on the entomological indicators of loiasis varies with bioecological zones. Community directed treatment with ivermectin induced a significant reduction in the entomological indicators of loiasis in the North-West project site which lies in forest savanna area. A non-significant decrease was observed in the East project site and in contrast, a significant increase was observed in the South-West 1 project site which both lies in the rainforest zones.

High‐resolution P‐ and S‐wavefield seismic investigations of a quick‐clay site in southwest of Sweden

AbstractSeismic investigations were performed at a site in the southwest of Sweden where major quick‐clay landslides have occurred in the past. Given the potential high risk of the area and the presence of medium infrastructures, the site posed a need for detailed investigations in a wide depth range and in high resolution. A high‐fold seismic survey was designed and conducted along two profiles using a 1–2 m receiver and shot spacing in order to retrieve both P‐ and S‐wavefield seismic images from vertical component data. The data were analysed by combining first‐break traveltime tomography and surface‐wave analysis as well as P‐ and S‐wavefield reflection seismic imaging. Using the first breaks, P‐wave velocity (VP) models were estimated, indicating the bedrock topography along the profiles and the sediment characteristics. The S‐wave velocity (Vs) models were estimated from the surface waves and indicated areas of low shear strength. Combined with VP and Vs models, this permits the estimation of VP/VS, a parameter that can indicate areas with high water content, significant for the detection of quick clays and possible liquefaction issues. The results are integrated with the P‐ and S‐wave reflection seismic images and compared with other geophysical investigations, such as magnetic and gravity data that were collected along the profiles.

Mobility of antimony in contrasting surface environments of a mine site: influence of redox conditions and microbial communities.

Microbial processes can influence the complex geochemical behaviour of the toxic metalloid antimony (Sb) in mining environments. The present study is aimed to evaluate the influence of microbial communities on the mobility of Sb from solid phases to water in different compartments and redox conditions of a mining site in southwest (SW) Spain. Samples of surface materials presenting high Sb concentrations, from two weathered mining waste dumps, and an aquatic sediment were incubated in slurries comparing oxic and anoxic conditions. The initial microbial communities of the three materials strongly differed. Incubations induced an increase of microbial biomass and an evolution of the microbial communities' structures and compositions, which diverged in different redox conditions. The presence of active bacteria always influenced the mobility of Sb, except in the neutral pH waste incubated in oxic conditions. The effect of active microbial activities in oxic conditions was dependent on the material: Sb oxic release was biologically amplified with the acidic waste, but attenuated with the sediment. Different bacterial genera involved in Sb, Fe and S oxidation or reduction were present and/or grew during incubation of each material. The results highlighted the wide diversity of microbial communities and metabolisms at the small geographic scale of a mining site and their strong implication in Sb mobility.

A Multi-Species Simulation of Mosquito Disease Vector Development in Temperate Australian Tidal Wetlands Using Publicly Available Data.

Worldwide, mosquito monitoring and control programs consume large amounts of resources in the effort to minimise mosquito-borne disease incidence. On-site larval monitoring is highly effective but time consuming. A number of mechanistic models of mosquito development have been developed to reduce the reliance on larval monitoring, but none for Ross River virus, the most commonly occurring mosquito-borne disease in Australia. This research modifies existing mechanistic models for malaria vectors and applies it to a wetland field site in Southwest, Western Australia. Environmental monitoring data were applied to an enzyme kinetic model of larval mosquito development to simulate timing of adult emergence and relative population abundance of three mosquito vectors of the Ross River virus for the period of 2018-2020. The model results were compared with field measured adult mosquitoes trapped using carbon dioxide light traps. The model showed different patterns of emergence for the three mosquito species, capturing inter-seasonal and inter-year variation, and correlated well with field adult trapping data. The model provides a useful tool to investigate the effects of different weather and environmental variables on larval and adult mosquito development and can be used to investigate the possible effects of changes to short-term and long-term sea level and climate changes.

P051Understanding medication abortion denial among a cohort of abortion clinic patients in southern california

<h3>Objectives</h3> Medication abortion is safe and effective up to 77 days' gestation. It is unknown how often patients who present for medication abortion do not receive one and whether those who are ineligible for medication abortion eventually receive surgical abortion. <h3>Methods</h3> We performed a retrospective cohort study of patients presenting for medication abortion at medication-abortion-only Planned Parenthood of the Pacific Southwest (PPPSW) sites from January to December 2021. PPPSW has 15 such clinics and two that offer surgical abortion. Patients seen at a medication-abortion-only site who were found ineligible after intake ultrasound (>70 days' gestation) were scheduled for an abortion at a surgical location. Electronic medical records were reviewed to determine medication abortion outcomes. <h3>Results</h3> Of 11,684 patients presenting for medication abortion at sites that only offered this service, 2,224 (19%) did not receive a medication abortion: 1,251 (56%) had an intrauterine pregnancy (IUP), 388 (17%) had a pregnancy of unknown location (PUL), and 116 (5%) had a non-viable pregnancy. Among those with an IUP, 426 (34%) presented at >70 days' gestation by ultrasound, and 223 (18%) between 71–77 days' gestation. Of these patients, 324 (76%) went on to receive a surgical abortion (54% dilation and curettage and 22% dilation and evacuation) after an average wait time of 10.5 days. <h3>Conclusions</h3> Even with a referral system in place, one-quarter of those presenting for medication abortion with an IUP at >70 days' gestation were lost to follow-up. Despite safety of medication abortion for patients with PUL, many of these patients did not receive one. Expanding medication abortion eligibility criteria by one week to 77 days' gestation and allowing medication abortion for PUL would expand access.

Cancer-Related Symptom Management Intervention for Southwest American Indians.

Simple SummaryQuality of life during, and even after, cancer treatment is greatly affected by cancer symptoms that include pain, fatigue, and changes to mental state and activities of daily living, to name a few. American Indians living in the Southwestern United States have cancer experiences which may be different than the general population and have long been understudied. A randomized controlled trial designed to test the impact of a culturally tailored intervention on the management of individual cancer symptoms was implemented. Outcomes included improvement in pain, depression, fatigue and loss of function management in adult American Indians. Study evaluations at post-test show a significant improvement in scores from pre-test and compared to the control group, demonstrating increased knowledge levels in managing cancer-related symptoms. Study findings guide researchers towards a better understanding of the meaning and impact of cancer symptoms for American Indian cancer survivors, thus their improving care and quality of life.There is limited literature related to culturally embedded meanings of cancer and related symptoms among American Indians. A culturally appropriate intervention to improve management of cancer-related symptoms, including pain, depression, fatigue and loss of function, was tested. Two-hundred and twenty-two adult American Indians with cancer were recruited from eight Southwest sites for a randomized clinical trial. The intervention group received tailored education, a toolkit with a video, and participated in discussion sessions on cancer symptom management; the control group received information on dental care. Pre- and post-test questionnaires were administered to control and intervention groups. Measures included socio-demographics, cancer-related symptom management knowledge and behavior, and quality of life measures. Male cancer survivors reported poorer self-assessed health status and lower scores on quality-of-life indicators as compared to female cancer survivors. Significant improvement was reported in symptom management knowledge scores following the intervention: management of pain (p = 0.003), depression (p = 0.004), fatigue (p = 0.0001), and loss of function (p = 0.0001). This study is one of the first to demonstrate a change in physical symptom self-management skills, suggesting culturally appropriate education and interventions can successfully enhance cancer-related symptom management knowledge and practice.

Correlates and Patterns of COVID-19 Vaccination Intentions among Parents of Children with Type 1 Diabetes.

ObjectiveTo examine psychosocial, sociodemographic, medical, and coronavirus disease 2019 (COVID-19) experiences as correlates of COVID-19 vaccination intentions among parents of children with type 1 diabetes (T1D).Methods121 parents of children with T1D (Mchild age = 7.78 ± 1.70; MA1c = 8.3% ± 1.5%) in the mid-Atlantic and Southwest regions completed self-report measures in February to March 2021.ResultsParents’ general vaccination behaviors and attitudes were associated with COVID-19 vaccination intentions. Child insurance type and social distancing adherence were associated with vaccination intention in the Southwest site. Higher A1c was associated with lower intention. Vaccine safety was the top reported concern.ConclusionsCOVID-19 vaccination intentions are important to address in parents of youth with health conditions.

Legume Cover Crop Contributions to Ecological Nutrient Management in Upper Midwest Vegetable Systems

Cover cropping, especially with legumes, is a critical approach to ecological soil nutrient management as a means to meet Sustainable Development Goal (SDG) 2, addressing food security issues via sustainable agriculture approaches. However, cover cropping in some of the most intensified food production regions of the northern U.S. is challenged by short growing seasons and harsh winters with variable temperatures and increasingly erratic snowfall. In this study, we explore the potential of winter annual legume cover crops to augment soil organic carbon (C) and nitrogen (N) stocks within a horticultural cropping system under climate conditions that allow only modest cover crop biomass production. We compared hairy vetch, cereal rye, red clover, and a hairy vetch/rye biculture in a randomized complete block design at two sites (North Central and Southwest Research and Outreach Centers in Minnesota) over 2 years. Cover crops were established in fall and terminated in spring prior to sweet corn planting, and soils sampled both at pre-cover crop termination and 2 weeks post-termination. We determined several indicators of C and N dynamics, including microbial biomass C (MBC), permanganate-oxidizable C (POXC), particulate organic matter C and N (POMC and POMN, respectively), extractable soil N (EXTN), and potentially mineralizable N (PMN). Out of all treatments evaluated, vetch production increased soil EXTN the greatest after 2 weeks, contributing two to 11 times more EXTN to soils compared to non-vetch treatments, meeting N requirements for sweet corn in three out of four site-years. Overall, time of sampling, either pre-or post-termination, consistently impacted soil measurements, with p &amp;lt; 0.05 in 20 out of 24 soil parameter × site-year combinations. Study results suggest that cover crops planted in colder northern climates during winter fallow periods can supply valuable N following spring termination, but termination effects on labile C and N pools are mixed. Our findings advance understanding of how cover cropping can support SDG 2 outcomes by assessing cover crop legume systems under biophysical conditions that challenge cover crop integration in agroecosystems.

Acoustic detection range of right whale upcalls identified in near-real time from a moored buoy and a Slocum glider.

The goal of this study was to characterize the detection range of a near real-time baleen whale detection system, the digital acoustic monitoring instrument/low-frequency detection and classification system (DMON/LFDCS), equipped on a Slocum glider and a moored buoy. As a reference, a hydrophone array was deployed alongside the glider and buoy at a shallow-water site southwest of Martha's Vineyard (Massachusetts, USA) over a four-week period in spring 2017. A call-by-call comparison between North Atlantic right whale upcalls localized with the array (n = 541) and those detected by the glider or buoy was used to estimate the detection function for each DMON/LFDCS platform. The probability of detection was influenced by range, ambient noise level, platform depth, detection process, review protocol, and calling rate. The conservative analysis of near real-time pitch tracks suggested that, under typical conditions, a 0.33 probability of detection of a single call occurred at 6.2 km for the buoy and 8.6-13.4 km for the glider (depending on glider depth), while a 0.10 probability of detection of a single call occurred at 14.4 m for the buoy and 22.6-27.5 km for the glider. Probability of detection is predicted to increase substantially at all ranges if more than one call is available for detection.

Effects of temperature and precipitation on litterfall phenology in four evergreen broad‐leaved forests of southern China

AbstractVegetative and reproductive growth of subtropical and tropical forests plays an important role in regulating carbon cycle and maintaining food web dynamic balance. Here, we used litterfall and climatic data during 1998–2017 at four evergreen forest sites in southern China to analyze temporal variations of community phenology and their climate drivers. Results show that two southwest forests have unimodal patterns with leaf litterfall peaks during dry season, while two southeast forests have bimodal patterns with the first peaks during rainy season and the second peaks during rainy and dry seasons respectively. Peaks of flower litterfall for the four forests occurred during the transitional period between dry and rainy seasons, while peaks of fruit litterfall appeared either at the end of the rainy season at the two southern sites or in the dry season at the two northern sites. Leaf litterfall correlates significantly positively with preseason maximum temperature at the four sites, but significantly negatively with preseason precipitation at two southwest sites. By contrast, flower and fruit litterfall correlates significantly positively with preseason temperature and precipitation at only three and two sites. Moreover, leaf, flower, and fruit litterfall exhibits a 12‐month cycle, which is consistent with the 12‐month cycle of monthly temperature and precipitation. Flower and fruit litterfall displays also multiyear cycles between 18 and 48 months, however, it is inconsistent with the multiyear cycles of monthly temperature and precipitation. Our study highlights that temperature and precipitation are key factors affecting litterfall variations in different time scales in southern China.Abstract in Chinese is available with online material.

Calibration of an evapotranspiration algorithm in a semiarid sagebrush steppe using a 3‐ha lysimeter and Landsat normalized difference vegetation index data

AbstractIn arid and semiarid environments, evapotranspiration (ET) is the primary discharge component in the water balance, with potential ET exceeding precipitation. For this reason, reliable estimates of ET are needed to construct accurate water budgets in these environments. Remote sensing affords the ability to provide fast, accurate, field‐scale ET estimates, but these methods have largely been restricted to deep rooted (phreatophytic) plant communities underlain by shallow groundwater. We used 13 years of data from a 3‐ha drainage lysimeter in a semiarid sagebrush steppe and Landsat normalized difference vegetation index (NDVI) data to calibrate a generalized least squares model capable of predicting vadose zone ET in a high elevation upland ecosystem. Annual precipitation was the best predictor of annual ET, as they were nearly balanced every year analysed (mean difference = 3 mm). We incorporated reference crop ET and a linear combination of NDVI and precipitation to capably predict ET on a subannual, lag‐determined interval of 48 days, with a mean error of only 9.92% across all observations. To our knowledge, this is the first vegetation index‐ET algorithm calibrated in a semiarid upland plant community using field‐scale lysimetry. Vadose zone ET is particularly important at waste disposal sites in the Desert Southwest, where accurate and spatially explicit ET estimates are needed for monitoring potential mobilization and transport of contaminants past the root zone into local aquifers and for monitoring and modelling effects of recharge on flow and transport of contaminants in underlying aquifers.

Satellite and UAV-based remote sensing for assessing the flooding risk from Tibetan lake expansion and optimizing the village relocation site

Climate change in recent decades led to the remarkable expansions for most lakes in endorheic basins of the Tibetan Plateau (TP). Enlarged lake inundation areas may pose adverse effects and potential threats on the local human living environment, especially for high-risk villages adjacent to rapidly expanding lakes. Taking a rapidly expanding lake, Angzi Co in the central TP as a study case, we investigated the flooding risk of lake growth on the local living environment and proposed an optimized solution of village relocation selection on the basis of satellite and unmanned aerial vehicle (UAV) remote sensing. The detection of spatiotemporal variations of Angzi Co using optical and altimetric satellite observations revealed a significant area and water level increase by 81.28 km2 and 5.78 m, respectively, from 2000 to 2020. We also assessed the vertical accuracy of multi-source digital elevation model (DEM) products using Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) altimetry data and further examined the flooding risk and potential influences of lake expansion on adjacent settlements (Guozha Village). Results indicated that UAV-DEM achieves excellent advantages in depicting details of lake shoreline variations and simulating potential submergence regions, followed by Advanced Land Observing Satellite World 3D DEM (AW3D DEM). Moreover, assuming that Angzi Co maintains the water level at a growth rate of 0.29 m/a (the average change rate during 2000–2020), the village will be submerged in approximate 10 years based on our assessment. Furthermore, we designed an optimal relocation site southwest of Guozha Village and approximately 3 km away based on the GIS-MVDA method and field investigations. An initial remote sensing-based approach for assessing the flooding risk from dramatic lake expansions in the TP and optimizing the village relocation site was proposed in this study to provide an essential scientific reference for formulating risk mitigation solutions under future climate change scenarios.

Heterogeneous CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; content of glacial meltwater from the Greenland Ice Sheet and implications for subglacial carbon processes

Abstract. Accelerated melting of the Greenland Ice Sheet has increased freshwater delivery to the Arctic Ocean and amplified the need to understand the impact of Greenland Ice Sheet meltwater on Arctic greenhouse gas budgets. We evaluate subglacial discharge from the Greenland Ice Sheet for carbon dioxide (CO2) and methane (CH4) concentrations and δ13C values and use geochemical models to evaluate subglacial CH4 and CO2 sources and sinks. We compare discharge from southwest (a sub-catchment of the Isunnguata Glacier, sub-Isunnguata, and the Russell Glacier) and southern Greenland (Kiattut Sermiat). Meltwater CH4 concentrations vary by orders of magnitude between sites and are saturated with respect to atmospheric concentrations at Kiattut Sermiat. In contrast, meltwaters from southwest sites are supersaturated, even though oxidation reduces CH4 concentrations by up to 50 % during periods of low discharge. CO2 concentrations range from supersaturated at sub-Isunnguata to undersaturated at Kiattut Sermiat. CO2 is consumed by mineral weathering throughout the melt season at all sites; however, differences in the magnitude of subglacial CO2 sources result in meltwaters that are either sources or sinks of atmospheric CO2. At the sub-Isunnguata site, the predominant source of CO2 is organic matter (OM) remineralization. However, multiple or heterogeneous subglacial CO2 sources maintain atmospheric CO2 concentrations at Russell but not at Kiattut Sermiat, where CO2 is undersaturated. These results highlight a previously unrecognized degree of heterogeneity in greenhouse gas dynamics under the Greenland Ice Sheet. Future work should constrain the extent and controls of heterogeneity to improve our understanding of the impact of Greenland Ice Sheet melt on Arctic greenhouse gas budgets, as well as the role of continental ice sheets in greenhouse gas variations over glacial–interglacial timescales.

The Inner Solar System Chronology (ISOCHRON) Lunar Sample Return Mission Concept: Revealing Two Billion Years of History

Abstract We present the Inner SOlar System CHRONology (ISOCHRON) concept to return samples of the youngest extensive mare basalt for age-dating and geochemical analysis. The young basalt is exposed at a site southwest of Aristarchus Plateau, for which complete remote-sensing data are available for thorough landing site analysis. Data from these samples would revolutionize the ability to assign exposure ages to rocky planetary surfaces based on the samples returned by Apollo and Luna. Their petrology and geochemistry will enable assessment of the most recent voluminous lunar magmatism. Regolith evolution and mixing models such as ballistic sedimentation would be directly testable to provide crucial ground truth that would enhance the science value of current and future remotely sensed data sets. ISOCHRON’s science goals support NASA’s Artemis program to return to the Moon and its related robotic programs currently in planning.

Meteorology-driven variability of air pollution (PM&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt;) revealed with explainable machine learning

Abstract. Air pollution, in particular high concentrations of particulate matter smaller than 1 µm in diameter (PM1), continues to be a major health problem, and meteorology is known to substantially influence atmospheric PM concentrations. However, the scientific understanding of the ways in which complex interactions of meteorological factors lead to high-pollution episodes is inconclusive. In this study, a novel, data-driven approach based on empirical relationships is used to characterize and better understand the meteorology-driven component of PM1 variability. A tree-based machine learning model is set up to reproduce concentrations of speciated PM1 at a suburban site southwest of Paris, France, using meteorological variables as input features. The model is able to capture the majority of occurring variance of mean afternoon total PM1 concentrations (coefficient of determination (R2) of 0.58), with model performance depending on the individual PM1 species predicted. Based on the models, an isolation and quantification of individual, season-specific meteorological influences for process understanding at the measurement site is achieved using SHapley Additive exPlanation (SHAP) regression values. Model results suggest that winter pollution episodes are often driven by a combination of shallow mixed layer heights (MLHs), low temperatures, low wind speeds, or inflow from northeastern wind directions. Contributions of MLHs to the winter pollution episodes are quantified to be on average ∼5 µg/m3 for MLHs below &lt;500 m a.g.l. Temperatures below freezing initiate formation processes and increase local emissions related to residential heating, amounting to a contribution to predicted PM1 concentrations of as much as ∼9 µg/m3. Northeasterly winds are found to contribute ∼5 µg/m3 to predicted PM1 concentrations (combined effects of u- and v-wind components), by advecting particles from source regions, e.g. central Europe or the Paris region. Meteorological drivers of unusually high PM1 concentrations in summer are temperatures above ∼25 ∘C (contributions of up to ∼2.5 µg/m3), dry spells of several days (maximum contributions of ∼1.5 µg/m3), and wind speeds below ∼2 m/s (maximum contributions of ∼3 µg/m3), which cause a lack of dispersion. High-resolution case studies are conducted showing a large variability of processes that can lead to high-pollution episodes. The identification of these meteorological conditions that increase air pollution could help policy makers to adapt policy measures, issue warnings to the public, or assess the effectiveness of air pollution measures.

Pollution assessment, spatial distribution and exposure of Cd and Pb in surface soils of abandoned landfill site in Gorgan, north of Iran

The purpose of the present research was Cadmium (Cd) and Lead (Pb) pollution assessment and monitoring the spatial distribution of soil ‎contamination around the municipal landfill site in southwest of Gorgan, Iran. Thus, in a systematic network with a distance of 250m, from 32 stations three samples of surface soil (0 to ‎‎20cm) were obtained and mixed together. In addition, three samples away from the landfill with similar ‎characteristics and geology were used as control. The concentration of heavy metals for the samples was determined using nitric acid and hydrochloric acid and atomic absorption spectrometry. Mean concentrations of Cd and Pb in the soil around the ‎landfill site were 0.37 and 17.31 mg/kg respectively. The total concentration of Cd and Pb was higher than the control areas. There was a positive correlation between Cd and Pb showing these elements in the soil are from the same origin. Based on our research, soil in the landfill area has a moderate ‎ecological risk index, which is about 120. The central parts of the study area have higher concentrations of Cd and Pb than southern parts due to the slope and runoff of the waste leachate. In general, there was an increase in the concentration of Cd and Pb in the sampling sites ‎compared to the control site.

Shifting signals: Correlations among freshwater, marine and climatic indices often investigated in Pacific salmon studies

The common practice of incorporating environmental indices into population models has greatly advanced our understanding of ecological systems. Unfortunately, we are increasingly seeing published correlations between population indicators and environmental indices breaking down when tested with new data. Examining how the correlations among indices change over time could help explain underlying causal mechanisms, which ultimately strengthen the basis for prediction of population indicators. For migratory animals such as anadromous salmon (Oncorhynchus spp.), the habitat conditions they experience can affect their lifetime fitness and population viability. We analyzed 43 freshwater, marine, and climate indices associated with 72 river sites and five coastal ecoregions inhabited by Chinook and coho salmon (O. tshawytscha and O. kisutch) in the western USA. Utilizing long time series (ranging from 32 to 124 years), we examined spatial and temporal patterns in correlations through hierarchical clustering across sites and non-stationarity across time. Individual river sites clustered into two Northwest and one Southwest groups. Northwest sites generally showed stronger correlations between freshwater and climate indices, while Southwest sites showed stronger correlations within freshwater or within marine/climate indices. For a closer examination at shorter periods, we parsed the time series into 10-year windows and showed how pairwise correlations changed over time with spring–summer Pacific Decadal Oscillation index in the Northwest and with spring flow in the Southwest. Stronger correlations across multiple indices tended to occur when large-scale climatic events (e.g., Oceanic Niño and Pacific Decadal Oscillation indices) were in-phase, and phase transitions (e.g., from positive to negative) occurred in the same 10-year window. In a third analysis, we assessed how well indices provided unique vs. confounding/complex information and had consistent vs. varying relationships based on the mean and variance of 10-year correlations. Across index types, the variance in correlations tended to be lowest in marine vs. climate indices, higher among freshwater indices, and highest for freshwater vs. marine/climate indices. Yet, the mean strength of correlations for freshwater vs. marine/climate indices was still comparable to those among freshwater ones. Overall, identifying time periods when correlations tend to change will help interpret historical and projected population indicators. Spatial trends in the strength of correlations also indicate that the level of confounding effects among indices can differ regionally. We emphasize the importance of knowing the strength and variability of correlations among indices, and their representativeness of ecological processes in the context of combined phases of multiple climatic indices.