Increasing comparability among coral bleaching experiments.

Coral bleaching is the single largest global threat to coral reefs worldwide. Integrating the diverse body of work on coral bleaching is critical to understanding and combating this global problem. Yet investigating the drivers, patterns, and processes of coral bleaching poses a major challenge. A recent review of published experiments revealed a wide range of experimental variables used across studies. Such a wide range of approaches enhances discovery, but without full transparency in the experimental and analytical methods used, can also make comparisons among studies challenging. To increase comparability but not stifle innovation, we propose a common framework for coral bleaching experiments that includes consideration of coral provenance, experimental conditions, and husbandry. For example, reporting the number of genets used, collection site conditions, the experimental temperature offset(s) from the maximum monthly mean (MMM) of the collection site, experimental light conditions, flow, and the feeding regime will greatly facilitate comparability across studies. Similarly, quantifying common response variables of endosymbiont (Symbiodiniaceae) and holobiont phenotypes (i.e., color, chlorophyll, endosymbiont cell density, mortality, and skeletal growth) could further facilitate cross-study comparisons. While no single bleaching experiment can provide the data necessary to determine global coral responses of all corals to current and future ocean warming, linking studies through a common framework as outlined here, would help increase comparability among experiments, facilitate synthetic insights into the causes and underlying mechanisms of coral bleaching, and reveal unique bleaching responses among genets, species, and regions. Such a collaborative framework that fosters transparency in methods used would strengthen comparisons among studies that can help inform coral reef management and facilitate conservation strategies to mitigate coral bleaching worldwide.

Vesicle shrinkage in hydrous phonolitic melt during cooling.

The ascent of hydrous magma prior to volcanic eruptions is largely driven by the formation of H2O vesicles and their subsequent growth upon further decompression. Porosity controls buoyancy as well as vesicle coalescence and percolation, and is important when identifying the differences between equilibrium or disequilibrium degassing from textural analysis of eruptive products. Decompression experiments are routinely used to simulate magma ascent. Samples exposed to high temperature (T) and pressure (P) are decompressed and rapidly cooled to ambient T for analysis. During cooling, fluid vesicles may shrink due to decrease of the molar volume of H2O and by resorption of H2O back into the melt driven by solubility increase with decreasing T at P < 300 MPa. Here, we quantify the extent to which vesicles shrink during cooling, using a series of decompression experiments with hydrous phonolitic melt (5.3-3.3 wt% H2O, T between 1323 and 1373 K, decompressed from 200 to 110-20 MPa). Most samples degassed at near-equilibrium conditions during decompression. However, the porosities of quenched samples are significantly lower than expected equilibrium porosities prior to cooling. At a cooling rate of 44 K·s-1, the fictive temperature T f, where vesicle shrinkage stops, is up to 200 K above the glass transition temperature (T g), Furthermore, decreasing cooling rate enhances vesicles shrinkage. We assess the implications of these findings on previous experimental degassing studies using phonolitic melt, and highlight the importance of correctly interpreting experimental porosity data, before any comparison to natural volcanic ejecta can be attempted.

Neurotic Personality Traits and Risk for Adverse Alcohol Outcomes: Chained Mediation through Emotional Disorder Symptoms and Drinking to Cope.

BACKGROUND: Rates of alcohol abuse are high on Canadian postsecondary campuses. Individual trait differences have been linked to indices of alcohol use/misuse, including neurotic traits like anxiety sensitivity (AS) and hopelessness (HOP). We know little, though, about how these traits confer vulnerability. AS and HOP are related to anxiety and depression, respectively, and to drinking to cope with symptoms of those disorders. Neurotic personality may therefore increase risk of alcohol use/abuse via (1) emotional disorder symptoms and/or (2) coping drinking motives. OBJECTIVES: Allan and colleagues (2014) found chained mediation through AS-generalized anxiety-coping motives-alcohol problems and AS-depression-coping motives-alcohol problems. We sought to expand their research by investigating how emotional disorder symptoms (anxiety, depression) and specific coping motives (drinking to cope with anxiety, depression) may sequentially mediate the AS/HOP-to-hazardous alcohol use/drinking harms relationships among university students. METHODS: This study used cross-sectional data collected in Fall 2014 as part of the Movember-funded Caring Campus Project (N = 1,883). The survey included the SURPS, adapted DMQ-R SF, and AUDIT-3. RESULTS: AS and HOP were both related to hazardous alcohol and drinking harms via emotional disorder symptoms and, in turn, coping drinking motives. All indirect pathways incorporating both mediators were statistically significant, and additional evidence of partial specificity was found. Conclusions/Importance: The study's results have important implications for personality-matched interventions for addictive disorders.

Exposure to overprotective parenting and psychopathology in extremely low birth weight survivors.

BACKGROUND: Extremely low birth weight (ELBW; <1,000 g) infants are the most vulnerable babies and are at higher risk for experiencing overprotective (i.e., controlling and intrusive) parenting, which is hypothesized to contribute to the risk for mental disorders. Despite the increased risk for anxiety disorders and decreased risk for alcohol or substance use disorders seen in ELBW survivors, no research has examined the impact of parenting. This study investigated if overprotective parenting mediates links between ELBW birth status and psychiatric disorders in adulthood. STUDY DESIGN: Participants included ELBW survivors born in 1977-1982 and matched normal birth weight (≥2,500 g) control participants (ELBW n = 81; normal birth weight n = 87) prospectively followed in Ontario, Canada. These individuals retrospectively reported on whether either of their parents was overprotective using the Parental Bonding Instrument. Presence of a current anxiety disorder and of current alcohol or substance use disorders was assessed using the Mini International Neuropsychiatric Interview at age 29-36 years. RESULTS: Path analysis showed that overprotective parenting was a significant mediator of the association between ELBW status and risk for an anxiety disorder in adulthood and the risk for an alcohol or substance use disorder in adulthood in ELBW survivors. Overprotective parenting accounted for 53% of the association between ELBW status and the risk for an anxiety disorder in adulthood and 26% of the association between ELBW status and alcohol or substance use disorders. CONCLUSIONS: Overprotective parenting accounted for a substantial proportion of the increased risk for anxiety and alcohol or substance use disorders in adulthood in ELBW survivors. Despite their perceived vulnerabilities, it is important that the parents of ELBW survivors be supported in their attempts to facilitate their children's pursuit of independence during childhood and beyond.

Frontal fibrosing alopecia: possible association with leave-on facial skin care products and sunscreens; a questionnaire study.

BACKGROUND: Since its first description in 1994, frontal fibrosing alopecia (FFA) has become increasingly common, suggesting that environmental factors are involved in the aetiology. OBJECTIVES: To identify possible causative environmental factors in FFA. METHODS: A questionnaire enquiring about exposure to a wide range of lifestyle, social and medical factors was completed by 105 women with FFA and 100 age- and sex-matched control subjects. A subcohort of women with FFA was patch tested to an extended British standard series of allergens. RESULTS: The use of sunscreens was significantly greater in the FFA group compared with controls. Subjects with FFA also showed a trend towards more frequent use of facial moisturizers and foundations but, compared with controls, the difference in frequencies just failed to reach statistical significance. The frequency of hair shampooing, oral contraceptive use, hair colouring and facial hair removal were significantly lower in the FFA group than in controls. Thyroid disease was more common in subjects with FFA than controls and there was a high frequency of positive patch tests in women with FFA, mainly to fragrances. CONCLUSIONS: Our findings suggest an association between FFA and the use of facial skin care products. The high frequency of sunscreen use in patients with FFA, and the fact that many facial skin care products now contain sunscreens, raises the possibility of a causative role for sunscreen chemicals. The high frequency of positive patch tests in women with FFA and the association with thyroid disease may indicate a predisposition to immune-mediated disease.

Does response propensity bias stress audits?

BACKGROUND: Non-response bias in surveys occurs when non-respondents differ from respondents. Methods of dealing with this include measuring 'response propensity'. We propose that response propensity has a trait-like component, measurable within the survey. Covariance of this component with survey items could indicate non-response bias. AIMS: To measure and validate trait-like response propensity, to test whether it co-varied with survey items during a routine stress audit and to test whether a prior staff attitude survey may have been biased. METHODS: Stress survey sent to government employees during a routine audit. We designed two new items to measure trait-like response propensity and completion of a prior staff survey. We calculated an odds ratio, correlations and Mann-Whitney U-tests to assess relationships between trait response propensity, completion of the prior staff survey and current stress survey scores. RESULTS: There were 71 respondents; response rate 68%. The trait response propensity item predicted completion of a prior staff survey (odds ratio 8.75, 95% confidence interval 2.32-33.08). Trait response propensity significantly correlated with two of the 40 survey items and did not significantly correlate with any of the eight 'stressor' sub-scales. Non-respondents to the prior staff survey had a significantly lower risk of stress on two of the eight stressor scales. CONCLUSIONS: Trait response propensity seems to be a valid construct. The weight of evidence does not provide an indication of non-response bias (yet neither does it assure freedom from non-response bias). The prior staff survey may have been affected by non-response bias.

Employing temporal self-similarity across the entire time domain in computed tomography reconstruction.

There are many cases where one needs to limit the X-ray dose, or the number of projections, or both, for high frame rate (fast) imaging. Normally, it improves temporal resolution but reduces the spatial resolution of the reconstructed data. Fortunately, the redundancy of information in the temporal domain can be employed to improve spatial resolution. In this paper, we propose a novel regularizer for iterative reconstruction of time-lapse computed tomography. The non-local penalty term is driven by the available prior information and employs all available temporal data to improve the spatial resolution of each individual time frame. A high-resolution prior image from the same or a different imaging modality is used to enhance edges which remain stationary throughout the acquisition time while dynamic features tend to be regularized spatially. Effective computational performance together with robust improvement in spatial and temporal resolution makes the proposed method a competitive tool to state-of-the-art techniques.

Spinal nociceptive reflexes are sensitized in the monosodium iodoacetate model of osteoarthritis pain in the rat.

OBJECTIVE: Evidence suggests that osteoarthritis (OA) is associated with altered central pain processing. We assessed the effects of experimentally induced OA on the excitability of spinal nociceptive withdrawal reflexes (NWRs), and their supraspinal control in a preclinical OA model. DESIGN: Experimental OA was induced in rats with knee injection of monosodium iodoacetate (MIA) and pain behaviour was assessed. 14/28 days post-MIA or saline injection, rats were anaesthetised for spinal NWR recording from tibialis anterior (TA) and biceps femoris (BF) hind limb muscles during plantar hind paw stimulation. Thresholds, receptive field sizes and wind up (incremental increase to repetitive stimulation) were measured in intact (d14/28) and spinalised (severed spinal cord; d28) MIA- and saline-injected rats. RESULTS: MIA reduced BF mechanical thresholds at day 28. Spinalisation of MIA rats did not prevent this hyperexcitability, and failed to produce the reduction in reflex receptive field (RRF) size observed in saline rats. These data indicate that MIA induces a hyperexcitability of BF NWR circuits that is maintained at the spinal level. In contrast, MIA appeared to have no effect on NWRs evoked by mechanical stimuli in the ankle flexor TA in intact rats, however spinalisation revealed hyperexcitability. Thus, 28 days following MIA-treatment, descending supraspinal inhibition normalised TA NWRs and was only overcome following repetitive noxious stimulation during wind up. CONCLUSIONS: We demonstrate that spinal nociceptive reflex pathways are sensitized following the development of OA, suggesting the presence of central sensitization. Further, our data reflect OA-induced alterations in the descending control of reflex responses. Our findings contribute to a mechanism-based understanding of OA pain.

Needs of the hidden homeless - no longer hidden: a pilot study.

OBJECTIVE: The purpose of this pilot study was to describe the health, housing and social service needs of the hidden homeless. It has been estimated that 80% of all people experiencing homelessness are hidden homeless, and because they remain 'hidden', resources are not allocated to provide this vulnerable population with support. STUDY DESIGN: This was a descriptive, case series research design. METHODS: Participants were recruited through agency referral and snowball sampling. Research ethics board (REB) approval was granted. Using descriptive statistics, information obtained from participant surveys was analysed using SPSS version 19. RESULTS: Thirty-four participants met the inclusion criteria and ranged from 15 to 69 years. Fifty percent of the participants reported first being homeless between 14 and 18 years of age. Participants had several comorbidities, including mental health challenges, dental and respiratory problems, and sleep disorders. Participants described several challenges with accessing adequate nutrition, and finding adequate transportation and finances, and did not list housing as a priority need. The most frequent barriers to accessing health and social services identified by participants included their personal challenges with addiction, lack of transportation, and the perceived stigma they experienced when they sought help from health and social service agencies. CONCLUSIONS: Findings from this study can contribute to the development of best practice guidelines and policies that specifically address the needs of this unique population. Improved allocation of resources and coordination of health and community services are cost-effective, and advance the overall health of the hidden homeless.

Nickel skin levels in different occupations and an estimate of the threshold for reacting to a single open application of nickel in nickel-allergic subjects.

BACKGROUND: Nickel is a frequent allergen throughout the world. However, the extent to which nickel is relevant as an occupational contact allergen as opposed to being simply a reflection of jewellery exposure has been unclear. Some thresholds for cutaneous nickel exposure to induce a dermatitis reaction in nickel-allergic individuals have been defined. Over recent years it has become possible to measure accurately the quantity of nickel on the skin of individuals in a number of occupations. OBJECTIVES: To measure the quantities of nickel on the skin of the fingers in workers employed in occupations for which nickel has been suspected as a contact allergen. To define the threshold for a dermatitis reaction after the single application of a quantity of nickel to the skin of nickel-allergic individuals when read at 2days. METHODS: We employed the 'finger immersion' technique for sample collection and induction coupled plasma mass spectrometry for the nickel measurement. Nickel platers, cashiers, sales assistants, caterers, healthcare assistants, office workers, dental nurses and hairdressers were studied (five in each group except for seven cashiers). A correction was made for the fact that the finger immersion method underestimates the amount of nickel on the fingertip. The threshold for reactivity to a single application of nickel was studied by the application of various concentrations of nickel (µgcm(-2) ) [0·05 (two subjects), 0·5 (two subjects), 2·5 (three subjects), 5·0 (21 subjects), 15 (19 subjects), 30 (19 subjects) and 45 (18 subjects)] in 21 subjects overall using Finn chambers on forearm skin. The reading was made at 2days and reactions were graded using the International Contact Dermatitis Research Group classification. RESULTS: Nickel levels on the fingers of platers, cashiers, sales assistants, caterers, and even office staff, were at or above the 0·035µgcm(-2) level at which 22% of nickel-allergic subjects will react (after applying a correction). The single open application of nickel study demonstrated a dose-response relationship, with no subjects reacting to ≤ 2·5µgcm(-2) , but increasing numbers reacting at the higher concentrations as follows: six of 21 (28%) at 5·0µgcm(-2) , six of 19 (31%) at 15µgcm(-2) , seven of 19 (37%) at 30µgcm(-2) and 11 of 18 (61%) at 45µgcm(-2) . CONCLUSIONS: This study confirms that nickel levels on the skin in coin handling occupations and some others are sufficient to induce an allergic contact dermatitis in some nickel-allergic subjects. A single application of 5µgcm(-2) when read at 2days induced a dermatitis reaction in six of 21 nickel-allergic subjects.

Investigation of the male pattern baldness major genetic susceptibility loci AR/EDA2R and 20p11 in female pattern hair loss.

BACKGROUND: The aetiology of female pattern hair loss (FPHL) is largely unknown. However, it is hypothesized that FPHL and male pattern baldness (AGA) share common susceptibility alleles. The two major susceptibility loci for AGA are the androgen receptor (AR)/ectodysplasin A2 receptor (EDA2R) locus on the X-chromosome, and a locus on chromosome 20p11, for which no candidate gene has yet been identified. OBJECTIVES: To examine the role of the AR/EDA2R and 20p11 loci in the development of FPHL using 145 U.K. and 85 German patients with FPHL, 179 U.K. supercontrols and 150 German blood donors. METHODS: Patients and controls were genotyped for 25 single nucleotide polymorphisms (SNPs) at the AR/EDA2R locus and five SNPs at the 20p11 locus. RESULTS: Analysis of the AR/EDA2R locus revealed no significant association in the German sample. However, a nominally significant association for a single SNP (rs1397631) was found in the U.K. sample. Subgroup analysis of the U.K. patients revealed significant association for seven markers in patients with an early onset (P = 0·047 after adjustment for the testing of multiple SNPs by Monte Carlo simulation). No significant association was obtained for the five 20p11 variants, either in the overall samples or in the analysis of subgroups. CONCLUSIONS: The observed association suggests that the AR/EDA2R locus confers susceptibility to early-onset FHPL. Our results do not implicate the 20p11 locus in the aetiology of FPHL.

A detailed surgical method for mechanical decerebration of the rat.

Surgical methods currently employed for the mechanical decerebration of a rat are only briefly described in the literature; hence, an information void exists for researchers wishing to adopt this technique successfully. Decerebration can lead to a high rate of mortality owing to cranial bleeding, particularly if the operator is inexperienced and uninformed. The illustrated methodology presented here describes, in detail, steps in the decerebration process and indicates effective approaches, such as reversible occlusion of a carotid artery, the combined use of tissue adhesive and haemostatic sponge, and perisurgical monitoring of blood pressure, by which to control blood loss and thus maintain mean postsurgical blood pressure within acceptable physiological parameters. By using this methodology, animal losses can be minimized, particularly in the early stages of adoption of the technique, ultimately reducing the numbers required for a study of this nature.

In situ observation of the percolation threshold in multiphase magma analogues.

Magmas vesiculate during ascent, producing complex interconnected pore networks, which can act as outgassing pathways and then deflate or compact to volcanic plugs. Similarly, in-conduit fragmentation events during dome-forming eruptions create open systems transiently, before welding causes pore sealing. The percolation threshold is the first-order transition between closed- and open-system degassing dynamics. Here, we use time-resolved, synchrotron-source X-ray tomography to image synthetic magmas that go through cycles of opening and closing, to constrain the percolation threshold Φ C at a range of melt crystallinity, viscosity and overpressure pertinent to shallow magma ascent. During vesiculation, we observed different percolative regimes for the same initial bulk crystallinity depending on melt viscosity and gas overpressure. At high viscosity (> 106 Pa s) and high overpressure (~ 1-4 MPa), we found that a brittle-viscous regime dominates in which brittle rupture allows system-spanning coalescence at a low percolation threshold (Φ C ~0.17) via the formation of fracture-like bubble chains. Percolation was followed by outgassing and bubble collapse causing densification and isolation of the bubble network, resulting in a hysteresis in the evolution of connectivity with porosity. At low melt viscosity and overpressure, we observed a viscous regime with much higher percolation threshold (Φ C > 0.37) due to spherical bubble growth and lower degree of crystal connection. Finally, our results also show that sintering of crystal-free and crystal-bearing magma analogues is characterised by low percolation thresholds (Φ C = 0.04 - 0.10). We conclude that the presence of crystals lowers the percolation threshold during vesiculation and may promote outgassing in shallow, crystal-rich magma at initial stages of Vulcanian and Strombolian eruptions.

Personality and prescription drug use/misuse among first year undergraduates.

Emerging adults (18-25 year olds) endorse the highest rates of prescription drug misuse. Attending college or university may confer additional risk. Previous research suggests that personality is an important predictor of many addictive behaviours. Four traits have been consistently implicated: anxiety sensitivity, hopelessness, sensation seeking, and impulsivity. Published studies on personality as a predictor of prescription drug abuse are limited, however, by a primary focus on overall prescription drug use, inconsistent operationalisation of misuse, and failure to control for alcohol use. Sample sizes have been small and non-specific. We sought to better understand how personality predicted the overall use, the medically-sanctioned use, and the misuse of prescription sedatives/tranquilizers, opioids, and stimulants. A large (N = 1755) sample of first year Canadian undergraduate students (mean age = 18.6 years; 68.9% female) was used. We predicted that: anxiety sensitivity would be related to sedatives/tranquilizers, hopelessness to opioids, sensation seeking to stimulants, and impulsivity to all three. Save for the impulsivity to opioid use path, predictions were fully supported in our "any use" model. For medically-sanctioned use: anxiety sensitivity predicted sedative/tranquilizers, hopelessness predicted opioids, and impulsivity predicted stimulants. For misuse: anxiety sensitivity (marginally) predicted sedatives/tranquilizers, sensation seeking predicted stimulants, and impulsivity predicted all three. Our models support using personality-matched interventions. Specifically, results suggest targeting anxiety sensitivity for sedative/tranquilizer misuse, sensation seeking for stimulant misuse, and impulsivity for unconstrained prescription drug misuse. Interventions with early coping skills that pertain to all four traits might be useful for preventing prescription drug uptake and later misuse.

Determinants and incidence of depression in multiple sclerosis: A prospective cohort study.

OBJECTIVE: To estimate the incidence and explore potential determinants of incidence of depression in MS. METHODS: A prospective cohort study used a sample of 192 patients from the southern Alberta MS clinic registry. Participants completed baseline risk factor assessment questionnaires using either online, mail or telephone surveys, and completed the Patient Health Questionnaire every 2weeks for 6months to assess depressive symptoms in real time. Risk factors assessed included biopsychosocial variables such as socioeconomic status, illness-related factors, childhood risk factors, psychosocial factors, and health behaviors. Cox proportional hazard models were fit to estimate predictors of incidence. RESULTS: 2-week incidence of depression for females was 0.019 (95% CI 0.013-0.029) and for males was 0.044 (0.026-0.074). Strongest predictor of depression incidence risk included fatigue impact, low mobility, resiliency, self-esteem, self-efficacy, and coping style. CONCLUSION: Depression in MS exhibits a risk factor profile similar to that of depression in the general population, with the additional impact of MS illness-related factors. Potentially modifiable risk factors, such as coping with stress and resiliency, present opportunities for focus of further research in depression in MS treatment and prevention efforts. Some differences in determinants of incidence were found compared to the prevalence risk factors, highlighting the danger of using cross-sectional data to make assumptions about risk. For example, the finding that depression incidence was higher for men is opposite to the higher depression prevalence estimates found for women as well as the consensus in the literature.

Different receptors mediate the electrophysiological and growth cone responses of an identified neuron to applied dopamine.

Neurotransmitters are among the many cues that may guide developing axons toward appropriate targets in the developing nervous system. We have previously shown in the mollusk Lymnaea stagnalis that dopamine, released from an identified pre-synaptic cell, differentially affects growth cone behavior of its target and non-target cells in vitro. Here, we describe a group of non-target cells that also produce an inhibitory electrophysiological response to applied dopamine. We first determined, using pharmacological blockers, which receptors mediate this physiological response. We demonstrated that the dopaminergic electrophysiological responses of non-target cells were sensitive to a D2 receptor antagonist, as are known target cell responses. However, the non-target cell receptors were linked to different G-proteins and intracellular signaling pathways than the target cell receptors. Despite the presence of a D2-like receptor at the soma, the growth cone collapse of these non-target cells was mediated by D1-like receptors. This study shows that different dopamine receptor sub-types mediated the inhibitory physiological and growth cone responses of an identified cell type. We therefore not only provide further evidence that D2- and D1-like receptors can be present on the same neuron in invertebrates, but also show that these receptors are likely involved in very different cellular functions.