Physical and Chemical Response of Small, North Temperate Lakes to Recovery From Acidification and Climate Change

As the rate of sulfate (SO42-) deposition continues to decline and climate is trending towards warmer and wetter conditions, the biogeochemical and physical response of small, north temperate lakes is variable. In this study, we observed long-term chemical trends combined with seasonal water temperature patterns in the context of climate change and recovery from acidification in two remote lake populations in Maine: 29 high elevation lakes and eight low elevation lakes. Small, temperate lakes are the most abundant type of lake, making them a widely representative study sample to consider. Maine’s high elevation lakes (\u3e600m) could potentially provide unique insight into the response of surface water chemistry to declining acidic deposition and interannual climate variability. The geochemical response in 29 lakes was analyzed during 30 years of change in sulfate (SO42-) deposition and climate. All 29 lakes exhibited positive trends in DOC from 1986-2015, and 19 of 29 lakes had statistically significant increases in DOC throughout the study period. These results illustrate a region-wide change from low DOC lakes (/L) to moderate DOC lakes (5-30 mg/L). Increasing DOC trends for these high elevation lakes were more consistent than for lower elevation lakes in the northeastern US. A linear mixed effects model demonstrated that lakewater SO42- and climate variables describe most of the variability in DOC concentrations (r2 = 0.78), and the strongest predictor of DOC concentration was an inverse relationship with SO42-. Due to SO42- concentrations trending towards pre-acidification levels and projections of a warmer, wetter, and more variable climate, there is uncertainty for the future trajectory of DOC trends in surface waters. Long-term monitoring of Maine’s high elevation lakes is critical to understand the recovery and response in surface water chemistry to a changing chemical and physical environment in the decades ahead. DOC trends in lower elevation lakes were more variable. We hypothesize this is attributed to different levels of SO42- deposition and availability of DOC in these watersheds, which varied in size and landscape character. We used high frequency temperature arrays to observe stratification dynamics during summer 2017. We hypothesized that lakes with higher DOC concentrations will exhibit a larger ratio of hypolimnion volume: total lake volume, and therefore have a larger volume of cold-water refugium that is less likely to warm or disappear over the course of a summer stratification period. We found the strongest predictors of percent change of hypolimnion volume ratio (HVR) were both the interaction of DOC concentration and maximum lake depth and just DOC concentration. This suggests that deeper and darker lakes are more likely to maintain larger hypolimnia and cold-water refugia over the course of summer stratification than shallower lakes. Schmidt stability quantifies the strength of stratification, and a significant, inverse relationship between mean Schmidt stability and percent change in (HVR) suggests that morphometry matters; lakes with greater stratification stability and simple basin morphometry are more likely to maintain larger hypolimnia throughout the course of summer stratification The disproportionately large contribution of small lakes to the global carbon cycle deem them an ideal system to observe and quantify changing DOC dynamics. Disentangling the effects of climate, acidification, and individual lake characteristics on small, north temperature lakes is critical to understanding the biogeochemical response of freshwater to a changing physical and chemical environment in the decades to come

Chronic Nuisance Ordinances: Turning Victims of Domestic Violence into Nuisances in the Eyes of Municipalities

Chronic nuisance ordinances are municipal ordinances that identify and terminate unwanted nuisance activities. Although chronic nuisance ordinances originally targeted households that harbored prolific drug use, many municipalities have broadened the scope of their ordinances to include a wide range of activities, including acts of domestic violence. As a result, domestic violence victims are now frequently deemed nuisances when they call the police for protection. Municipalities, to abate the nuisances, evict the domestic violence victims from their homes. Because chronic nuisance ordinances are gaining in popularity throughout the country, an increasing number of domestic violence victims are being victimized twice: once by their abusers and again by their municipalities. This Comment explores the objectives, validity, and effects of chronic nuisance ordinances. This Comment also analyzes several arguments that have been used to challenge the constitutionality of these ordinances. Ultimately, this Comment recommends that municipalities avoid chronic nuisance ordinances entirely, but in the alternative, recommends several strategies for limiting the ordinances\u27 harmful effects

The Impact of Intensive Genetic Selection for Improved Performance in the Broiler Chicken on Metabolic Rate, Morphology and Body Composition

The intensive genetic selection for fast growth rate, improved feed conversion ratio and increased breast meat yield that broilers have undergone has resulted in an increased incidence of metabolic disorders. It has been hypothesised that this is due to an imbalance in form and function between supply and demand tissues, known as symmorphosis. Such a breakdown in symmorphosis may also have consequences in limiting future performance. The effects of genetic selection on the gross morphology (organ mass), metabolic rates and carcass composition of three genotypes of chicken, which have undergone selection on different criteria, were examined. In addition, the use of near-infrared spectroscopy (NIRS) was investigated as an alternative technique for assessing the chemical composition of chicken carcasses. The experimental studies described within this thesis investigated the effects of the intensive genetic selection in the modem broiler by comparing it with two other genotypes of chicken that have undergone different levels of selection. These included: a modem commercial broiler (Ross 308, FB), a broiler that has not been selected for fast growth since 1972 (Ross 1972, SB) and a layer chicken which has never been selected for fast growth rate (Euribrid HISEX, L). A thermal load was placed on the birds to evaluate the effects of genetic selection on metabolic rate. Metabolic rate was determined using open-circuit indirect calorimetry to measure oxygen consumption (VO2). Resting (RMR) and peak metabolic rate (PMR) were measured in each individual bird on the same day during the first 2 weeks of life. Resting metabolic rate was determined by measuring VO, of the birds at thermoneutrality (28-3

Prefrontal cortex haemodynamics and affective responses during exercise: a multi-channel near infrared spectroscopy study

The dose-response effects of the intensity of exercise upon the potential regulation (through top-down processes) of affective (pleasure-displeasure) responses in the prefrontal cortex during an incremental exercise protocol have not been explored. This study examined the functional capacity of the prefrontal cortex (reflected by haemodynamics using near infrared spectroscopy) and affective responses during exercise at different intensities. Participants completed an incremental cycling exercise test to exhaustion. Changes (Δ) in oxygenation (O2Hb), deoxygenation (HHb), blood volume (tHb) and haemoglobin difference (HbDiff) were measured from bilateral dorsal and ventral prefrontal areas. Affective responses were measured every minute during exercise. Data were extracted at intensities standardised to: below ventilatory threshold, at ventilatory threshold, respiratory compensation point and the end of exercise. During exercise at intensities from ventilatory threshold to respiratory compensation point, ΔO2Hb, ΔHbDiff and ΔtHb were greater in mostly ventral than dorsal regions. From the respiratory compensation point to the end of exercise, ΔO2Hb remained stable and ΔHbDiff declined in dorsal regions. As the intensity increased above the ventilatory threshold, inverse associations between affective responses and oxygenation in (a) all regions of the left hemisphere and (b) lateral (dorsal and ventral) regions followed by the midline (ventral) region in the right hemisphere were observed. Differential activation patterns occur within the prefrontal cortex and are associated with affective responses during cycling exercise

A Function Acquisition Speed Test for Equivalence Relations.

The current study employed a stimulus equivalence paradigm to assess the ability of the recently developed Function Acquisition Speed Test (FAST) to measure the existence and strength of experimentally produced derived relations. Twenty-two participants were exposed to a One-to-Many stimulus equivalence training procedure (A1–B1, A1–C1, A2–B2, A2–C2), followed by testing for derived B1–C1 and B2–C2 relations. All participants were then exposed to a FAST procedure in which a simple common operant response was established for pairs of equivalent stimuli (e.g., B1 and C1) in one block of training. In another bock of training, a common response was established for pairs of non-equivalent stimuli (e.g., B1 and C2). Trial numbers required for participants to reach mastery criteria differed across the two FAST blocks, as expected, but only for those participants who had passed the prior equivalence testing phase. This finding suggest that the FAST procedure functions as both a concurrent measure of stimulus equivalence class emergence and a functional-analytic tool that might assess unreinforced and socially sensitive stimulus relations formed in the world outside the laboratory. Large inter- and intra-participant variations in performances across FAST blocks are discussed

High Levels of Oxidative Stress and Skin Microbiome are Critical for Initiation and Development of Chronic Wounds in Diabetic Mice.

A balanced redox state is critical for proper healing. Although human chronic wounds are characterized by high levels of oxidative stress (OS), whether OS levels are critical for chronic wound development is not known. For these studies, we used our chronic wound model in diabetic mice that has similar characteristics as human chronic wounds, including naturally developed biofilm. We hypothesize that OS levels in wound tissues are critical for chronic wound initiation and development. We show that increased OS levels in the wound correlate with increased chronicity. Moreover, without increased OS levels, biofilm taken from chronic wounds and placed in new excision wounds do not create chronic wounds. Similarly, high OS levels in the wound tissue in the absence of the skin microbiome do not lead to chronic wounds. These findings show that both high OS levels and bacteria are needed for chronic wound initiation and development. In conclusion, OS levels in the wound at time of injury are critical for biofilm formation and chronic wound development and may be a good predictor of the degree of wound chronicity. Treating such wounds might be accomplished by managing OS levels with antioxidants combined with manipulation of the skin microbiome after debridement

Playing by white rules of racial equality:student athlete experiences of racism in British university sport

Inequalities related to racial identity are consistently reported across social institutions, not least education, and sport. These inequalities consistently challenge ‘post-race’ narratives that rationalise racism down to individual prejudices and poor decision-making. This paper presents part of the findings from a wider a twelve-month research project commissioned by British University and Colleges Sport (BUCS) to explore race equality. This wider research privileged the voices of non-White students and staff in an exploration of race and equality in British UK university sport. ‘Non-white’ was chosen as a race identifier to focus on Whiteness, the normalised, raceless power that reproduces itself both knowingly and unknowingly, to ensure racial ‘others’ remain subordinate. This paper presents the findings of the student voices. In this study a research team of academic and student researchers explored the experiences of 38 students across five universities. Generating case studies from each university, the data was analysed from an Intersectional and Critical Race Theory perspective. Two core themes relating to negotiating Whiteness were developed from the data analysis which reflected experiences of university sport as predominantly White spaces; ‘Play by the Rules’ and ‘Keep You Guessing’. Racial abuse was subtle, camouflaged in comments and actions that happened momentarily and hence were implausible to capture and evidence. For incidents to be addressed, evidence had to meet a ‘beyond doubt’ standard. Students were required to consciously negotiate racial bias and abuse to ensure they did not provide a justification for abuse. Navigating racialisation and stereotypes, plus White denial, was additional emotional labour for students. This mechanism of silencing the victim served to normalise racism for both the abused and perpetrator. The conclusion explores potential ways of disrupting these mechanisms of Whiteness in placing students’ welfare at the heart of university sport

FcγRI-Deficient Mice Show Multiple Alterations to Inflammatory and Immune Responses

AbstractThe inactivation of the mouse high-affinity IgG Fc receptor FcγRI resulted in a wide range of defects in antibody Fc-dependent functions. These studies showed the primary importance of FcγRI in endocytosis of monomeric IgG, kinetics, and extent of phagocytosis of immune complexes, in macrophage-based ADCC, and in immune complex-dependent antigen presentation to primed T cells. In the absence of FcγRI, antibody responses were elevated, implying the removal of a control point by the deletion of FcγRI. In addition, FcR-γ chain-deficient mice were found to express partially functional FcγRI. Thus, FcγRI is an early participant in Fc-dependent cell activation and in the development of immune responses