Free radical and overtone spectroscopy

In the fall of 1987 during a photoacoustic study of hydrogen peroxide's fourth vibrational overtone band, the remarkably clear and well resolved spectrum was observed. Its periodicity and K subband structure suggested that the spectrum was not of hydrogen peroxide but of a smaller near-prolate symmetric top molecule. Furthermore, the time dependent behavior of the signal indicated that chemical changes were taking place within the photoacoustic apparatus

SLIDES: UK Climate Policy

Presenter: James Reilly, Senior Energy & Environment Advisor, British Embassy, Washington DC. 28 slides. Contains references

Cortical Contributions to the Age-Related Decline in Contrast Sensitivity

A signal detection paradigm was employed to investigate the possibility that changes in decision-making may contribute to the age-related decline in contrast sensitivity. Detection of sinusoidal grating patterns was measured at 3 and 15 c/deg for a range of contrasts which were psychophysically equivalent for young and old subjects. A decline in contrast sensitivity with age at the spatial frequencies studied was confirmed for contrast thresholds obtained both by an ascending method and from the 50% hit rate for detection of the grating pattern. The criterion adopted for decision-making, expressed as both B and percentage bias, did not change significantly between young and old subjects at 15 c/deg. At 3 c/deg, criterion did not change significantly at 0. 8x, 1.0x, or 1.2x contrast threshold, but at contrast giving 50% hit rate there was a significant increase with age. Paradoxically, the percentage bias increased significantly at contrast threshold but not at 50% hit rate. It is inferred from the results that the loss of contrast sensitivity is not accountable in terms of adoption of a more conservative criterion by older subjects. Hence visual loss in ageing is attributed to changes within the visual pathway rather than within higher decision-making centres. In order to further investigate this conclusion, the transient pattern visually evoked response (PVER) was recorded in young and old subjects to the onset of a vertical sinusoidal grating pattern of spatial frequency 3 and 8 c/deg and contrasts 40%, 20%, 10%, 5% and 3%. The waveform evoked contained a series of negative and positive components which were labelled N1, P1, N2 and P2. The latencies of the N1, P1 and N2 components were generally found to be significantly longer in old subjects compared with young, while no significant age-related differences were found for P2. Amplitudes and rise times were not found to be significantly different between the age groups. Latencies of the first 3 components generally generally showed a significant inverse correlation with log contrast although the 'gain' of the relationship was not significantly different between young and old subjects. Amplitude and rise time showed no significant correlation with log contrast. The age-related latency changes were confirmed when PVERs to grating patterns of 40% contrast and spatial frequencies 1, 2, 3, 5, 8, 10 and 15 c/deg were recorded in young and old subjects. The latencies of N1 and P1 were found to be significantly correlated with increasing spatial frequency. Rise times of P1 and N2 were significantly inversely correlated with spatial frequency. Amplitudes of P1 and N2 showed a significant inverse correlation with spatial frequency only in young subjects. Age-related latency changes in the flash VER are interpreted in terms of a possible decline in cortical inhibitory function in old subjects. PVERs were also recorded to grating patterns of 3 and 8 c/deg, the contrasts of which were normalized with respect to contrast threshold and hence were psychophysically comparable between subjects of different ages. At 8 c/deg there were no significant latency, amplitude or rise time differences between young and old subjects. At 3 c/deg, however, the age-related latency differences were maintained, even though the stimuli had been made perceptually equivalent. The results indicate that the location of at least some of the physiological changes underlying the age-related deficit in visual performance must lie in or prior to the primary visual cortex where the early components of the PVER are thought to be generated. In addition, it is concluded that the results in the signal detection experiment where contrast thresholds obtained from the 50% hit rate at 3 c/deg (but not 15 c/deg) were higher than expected in old subjects, and the results in the PVER experiments where normalizing stimulus contrast failed to abolish age-related latency differences at 3 c/deg (but not 8 c/deg), can best be explained by an impairment in old people in the processing of transient stimuli at low spatial frequency

Risk and Protective Factors of Delinquency: Perspectives from Professionals Working with Youth

This study examines the risk factors that increase an adolescent’s chance of engaging in delinquency and the protective factors that reduce the risk of delinquency. The risk and protective factors were examined through the ecological paradigm, which included the individual, family/peers, and neighborhood/community domains. This study used a qualitative method to examine the risk and protective factors through the perspective of professionals working in the juvenile justice system. Data was collected from a sample of professionals working at all levels of the juvenile justice system (N=6, average length of experience in working with youth=21 years), which included juvenile judges, assistant county attorneys, and probation officers. This study has found that professionals, who are responsible for the decision-making in the juvenile justice system, base their decision-making on the risk and protective factors that a youth presents. The study has also revealed that youth in the criminal justice possess more risk factors than protective factors. Risk and protective factor themes are identified in each of the domains. Implications for social work and interventions within each domain are discussed

The End of an Era

Les images nostalgiques et les souvenirs de Damas évoqués dans des représentations récentes sont pour la plupart établis à partir d’une vision de l’état de la ville remontant à fin de la période ottomane. Ainsi, vue de la perspective de la fin du xxe siècle et du début du xxie siècle, la fin de la période ottomane peut nous sembler avoir été « traditionnelle », alors que les damascènes ont éprouvé des changements importants et dramatiques, préludes à une nouvelle ère débutée dans les années 1830. Au cours de cette décennie, les différents contextes, dans lesquels les damascènes vivaient depuis un siècle, commencèrent rapidement à s’altérer. Fondé principalement sur les registres des tribunaux šarʿī, cet article examine les modèles de la vie économique et sociale de la ville de Damas tels qu’ils apparaissent à la fin des années 1820 avant l’invasion égyptienne et les réformes des Tanzimat ottomans qui suivirent.Nostalgic images and memories of Old Damascus invoked in recent representations are mostly dated from the later Ottoman period. From the perspective of the late 20th and early 21st centuries, the later Ottoman period may appear to have been “traditional”. In fact, Damascenes had been experiencing significant and dramatic changes that heralded a new era beginning in the 1830s. During that decade century old living conditions of Damascenes altered rapidly. This article is mainly based on sharia court records. It article examines patterns of Damascene economic and social life as they appeared in the late 1820s, before Egyptian invasion, and the subsequent Ottoman Tanzimat reforms.إن صور الحنين لدمشق وذكرياتها التي ذكرت في التماثيل الحديثة قد تمّ إعدادها في معظمها انطلاقاً من رؤية لحال المدينة تعود إلى نهاية العصر العثماني. وهكذا، إذا نظرنا من خلال منظور نهاية القرن العشرين وبداية القرن الحادي والعشرين، فمن الممكن أن تبدو لنا نهاية العصر العثماني «تقليدية»، بينما أحسّ الدمشقيون بتغيّرات هامة ومؤثرة كانت مدخلاً لحقبة جديدة بدأت في ثلاثينيات القرن التاسع عشر. خلال هذا العقد من الزمن، بدأ سياق الوقائع الذي كان يعيشه الدمشقيون منذ قرن من الزمن، يتغير بسرعة نحو الأسوأ. اعتماداً بشكل أساسي على سجلات المحاكم الشرعية تدرس هذه المقالة بإمعان نماذج الحياة الاقتصادية والاجتماعية لمدينة دمشق كما تبدو في نهاية عشرينيات القرن التاسع عشر، قبل الغزو المصري وإصلاحات التنظيمات العثمانية التي تلته

The Expression of ICER Under the Control of the Ovarian CYP19A1 Promoter in Zebrafish Ovaries Danio rerio

Infertility, according to the World Health Organization, is defined as the failure to conceive after twelve months of regular unprotected sexual intercourse. A recent study measuring the prevalence of female infertility estimated that 48.5 million women were affected globally (World Health Organization). To even begin to understand infertility is a colossal undertaking. Before we can hope to cure this disorder in humans we must first understand its pathogenesis in animal models. For this purpose, a study will be undertaken in zebrafish, Danio rerio, a popular model organism for reproductive studies (Segner, 2009). Based on a previous study in mouse models the ICER (inducible cAMP early repressor) protein has been identified as a potentiator of hyperovulation in mice (Muñiz). The ICER protein is an inducible early repressor of the cAMP second messenger system and a dominant negative autoregulator of its own expression (Molina, 1993). Based on the results of the Muñiz study, the present research will focus on the expression of ICER in zebrafish ovaries. First, it was proven via protein and RNA expression analysis that ICER is expressed in a stage-dependent manner in the zebrafish ovary during folliculogenesis. Next, based on this expression profiling, an ICER plasmid vector was designed with ICER under the control of the cyp19a1 ovarian-specific promoter. Cyp19a1 is a gonadotropin and estrogen inducible promoter predominantly expressed in the zebrafish ovary (Kazeto, 2001). This plasmid vector can be utilized in the future, in conjunction with the Tol2 transposase system in zebrafish, to study the effects of ICER overexpression in the ovary and hopefully elucidate some further understanding of the causes and pathology of infertility as well as possible treatment scenarios (Kawakami, 2007)

Risk and Protective Factors of Delinquency: Perspectives from Professionals Working with Youth

This study examines the risk factors that increase an adolescent’s chance of engaging in delinquency and the protective factors that reduce the risk of delinquency. The risk and protective factors were examined through the ecological paradigm, which included the individual, family/peers, and neighborhood/community domains. This study used a qualitative method to examine the risk and protective factors through the perspective of professionals working in the juvenile justice system. Data was collected from a sample of professionals working at all levels of the juvenile justice system (N=6, average length of experience in working with youth=21 years), which included juvenile judges, assistant county attorneys, and probation officers. This study has found that professionals, who are responsible for the decision-making in the juvenile justice system, base their decision-making on the risk and protective factors that a youth presents. The study has also revealed that youth in the criminal justice possess more risk factors than protective factors. Risk and protective factor themes are identified in each of the domains. Implications for social work and interventions within each domain are discussed

Comparison of accelerometer measured levels of physical activity and sedentary time between obese and non-obese children and adolescents: a systematic review

Background: Obesity has been hypothesized to be associated with reduced moderate-to-vigorous physical activity (MVPA) and increased sedentary time (ST). It is important to assess whether, and the extent to which, levels of MVPA and ST are suboptimal among children and adolescents with obesity. The primary objective of this study was to examine accelerometer-measured time spent in MVPA and ST of children and adolescents with obesity, compared with MVPA recommendations, and with non-obese peers. Methods: An extensive search was carried out in Medline, Cochrane library, EMBASE, SPORTDiscus, and CINAHL, from 2000 to 2015. Study selection and appraisal: studies with accelerometer-measured MVPA and/or ST (at least 3 days and 6 h/day) in free-living obese children and adolescents (0 to 19 years) were included. Study quality was assessed formally. Meta-analyses were planned for all outcomes but were precluded due to the high levels of heterogeneity across studies. Therefore, narrative syntheses were employed for all the outcomes. Results: Out of 1503 records, 26 studies were eligible (n = 14,739 participants; n = 3523 with obesity); 6/26 studies involved children aged 0 to 9 years and 18/26 involved adolescents aged 10.1 to19 years. In the participants with obesity, the time spent in MVPA was consistently below the recommended 60 min/day and ST was generally high regardless of the participant’s age and gender. Comparison with controls suggested that the time spent in MVPA was significantly lower in children and adolescents with obesity, though differences were relatively small. Levels of MVPA in the obese and non-obese were consistently below recommendations. There were no marked differences in ST between obese and non-obese peers. Conclusions: MVPA in children and adolescents with obesity tends to be well below international recommendations. Substantial effort is likely to be required to achieve the recommended levels of MVPA among obese individuals in obesity treatment interventions

TSPO ligands promote cholesterol efflux and suppress oxidative stress and inflammation in choroidal endothelial cells

Choroidal endothelial cells supply oxygen and nutrients to retinal pigment epithelial (RPE) cells and photoreceptors, recycle metabolites, and dispose of metabolic waste through the choroidal blood circulation. Death of the endothelial cells of the choroid may cause abnormal deposits including unesterified and esterified cholesterol beneath RPE cells and within Bruch’s membrane that contribute to the progression of age-related macular degeneration (AMD), the most prevalent cause of blindness in older people. Translocator protein (TSPO) is a cholesterol-binding protein that is involved in mitochondrial cholesterol transport and other cellular functions. We have investigated the role of TSPO in choroidal endothelial cells. Immunocytochemistry showed that TSPO was localized to the mitochondria of choroidal endothelial cells. Choroidal endothelial cells exposed to TSPO ligands (Etifoxine or XBD-173) had significantly increased cholesterol efflux, higher expression of cholesterol homeostasis genes (LXRα, CYP27A1, CYP46A1, ABCA1 and ABCG1), and reduced biosynthesis of cholesterol and phospholipids from [14C]acetate, when compared to untreated controls. Treatment with TSPO ligands also resulted in reduced production of reactive oxygen species (ROS), increased antioxidant capacity, and reduced release of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and VEGF) induced by oxidized LDL. These data suggest TSPO ligands may offer promise for the treatment of AMD