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Background: Evidence for the longer-term benefits of online mindfulness training for medical students, including in the reduction of stress and improved wellbeing, is limited. This study aimed to evaluate the impact of a novel online mindfulness training program on trait mindfulness, wellbeing and study engagement of medical students at program completion and 6-month follow-up. Methods: This was a randomised waitlist control study of an 8-week, online, mindfulness-based intervention versus normal curriculum alone for medical students (N = 114). The primary outcome measures were the changes from baseline to program completion at Week 8 for self-reported trait mindfulness (Freiburg Mindfulness Inventory), perceived stress (Perceived Stress Scale), self-compassion (Self-Compassion Scale) and study engagement scores (Utrecht Work Engagement Scale for Students). The secondary outcome measures were these score changes from baseline to 6-month follow up. Intervention and control students completed surveys at all three time points. Program adherence (Mindfulness Adherence Questionnaire) was also measured in the intervention group. Results: The intervention group experienced modest but statistically significant improvements in mindfulness (9%, p = 0.0002), self-compassion (5%, p = 0.026), and study engagement (4%, p = 0.035) from baseline to Week 8. They also reported a sustained improvement of 5% (p = 0.017) in mindfulness scores at 6 months. The control group reported no significant changes at Week 8 or 6 Months. Between-group comparisons showed that compared to the control group, the intervention group improved significantly more in mindfulness (p = 0.0076), and statistically marginally more in study engagement (p = 0.0534) at Week 8. No statistically significant between-group differences were observed at 6 months. Conclusions: These results add to the small but growing body of evidence suggesting that online mindfulness-based interventions with minimal contact can improve, albeit in modest magnitude, mindfulness and possibly study engagement in medical students for the duration of a mindfulness program. Further refinements to the program may be important to maintain improvements in the longer-term. Trial registration: Registration number ACTRN12624000783527. [ABSTRACT FROM AUTHOR]

The Hudson River (HR) Estuary has a long history of pollution with a variety of contaminants including PCBs and dioxins. In fact, 200 miles of the mainstem HR is designated a U.S. federal Superfund site, the largest in the nation, because of PCB contamination. The tidal HR hosts the southernmost spawning population of Atlantic tomcod, Microgadus tomcod, and studies revealed a correlation between exposure of juveniles to warm water temperature during summer to abundance of spawning adults of the same cohort in the following winter. Further, a battery of mechanistically linked biomarkers, ranging from the molecular to the population levels, were significantly impacted from contaminant exposures of the HR tomcod population. In response to xenobiotic insult, the HR tomcod population developed resistance to PCB and TCDD toxicity resulting from a deletion in the aryl hydrocarbon receptor2 (AHR2) gene. Furthermore, RNA-Seq analysis of global gene expression demonstrated that effects of the AHR2 polymorphism were far more pervasive than anticipated. The most highly PCB-contaminated sediments in the upper HR were dredged between 2009 and 2015 with the objective of lowering PCB concentrations in fishes in the lower HR. Success of the remediation project has been controversial. These observations suggest that tomcod provides an informative model to evaluate the efficacy of HR PCB remediation efforts on downriver fish populations and possible interactive effects between contaminant exposure and a warming environment. [ABSTRACT FROM AUTHOR]

Introduction: Student wellbeing is a growing concern for physiotherapy and other health professional students, with potential impacts on academic success, patient care and future personal wellbeing. The purpose of this study was to determine the predictors of future stress, anxiety, depression, study engagement and academic performance in physiotherapy students, including a subgroup who undertook a mindfulness training program. Methods: Predictors of outcome were obtained from a prospective cohort study involving 83 penultimate-year physiotherapy students, who could volunteer to participate in a 6-week mindfulness training program during semester (n = 17) or complete outcome measures without mindfulness training (n = 66). Baseline predictors of outcome were obtained at the start of Semester 1: age, gender, trait mindfulness, study engagement, training (mindfulness training or no training), stress, anxiety and depression. Outcomes were measured at the end of Semester 1 (study engagement, stress, anxiety, depression, grade point average) and at the end of the course (grade point average). Multiple regression was used to determine the ability of baseline characteristics to predict outcomes. Results: Psychological distress (stress, anxiety and depression) increased across the full study cohort between the start and end of the semester as exams approached (p < .05). Completion of mindfulness training was significantly associated with better academic performance and lower levels of depression at follow-up. Female gender, lower baseline depression scores and higher study engagement were also significant predictors of superior academic performance, while older age and higher trait mindfulness predicted greater study engagement at end of semester (p < .05). Conclusions: Potentially modifiable factors (study engagement, depression and mindfulness training) were associated with future wellbeing and academic success in physiotherapy students. Further research is warranted to explore interventions to address these outcomes in randomised controlled trials. [ABSTRACT FROM AUTHOR]

Sturgeon populations worldwide are threatened with extirpation but little is known about their tendency to bioaccumulate contaminants and their sensitivities to environmental burdens of these contaminants. Shortnose sturgeon and Atlantic sturgeon, two species that are federally endangered in the USA, co-occur in the Hudson River (HR) where high sediment levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-p-furans (PCDFs) occur. Previous controlled laboratory studies showed that young life-stages of both species are sensitive to toxicities at low levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and PCB126 exposure. The objective here was to measure congener-specific hepatic levels of PCBs and PCDD/Fs in HR specimens in order to determine if in situ bioaccumulation of these compounds is sufficiently high to have caused the early life-stage toxicities previously observed. Estimates of hepatic burdens of PCBs and PCDD/Fs were obtained from a small number of specimens of each species collected between 2014 and 2016 and specimens of shortnose sturgeon collected over 30 years earlier and archived in a museum collection. Several significant patterns emerged. Hepatic levels of legacy PCBs and PCDDs were low in specimens of both species but typically higher in shortnose than Atlantic sturgeon, a pattern consistent with their habitat use in the HR. Hepatic burdens in shortnose sturgeon tended to be higher in archived specimens than in more recently collected ones despite expected reduction in archived specimens due to preservation methods. Several inadvertent PCBs congeners were detected at high levels, including PCB11, but their toxicity to natural populations remains unknown. Levels of select PCDFs congeners, 2,3,7,8-TCDF and 2,3,4,7,8 PeCDF, were elevated in some shortnose sturgeon individuals from the HR. Using Relative Potency (ReP) factors derived from white sturgeon, the observed levels of some hepatic PCDFs in HR shortnose sturgeon may have been sufficiently high to impair recruitment of young life-stages in this ecosystem. [ABSTRACT FROM AUTHOR]

Several methods have been devised to mitigate the effects of outlier values on survey estimates. If outliers are a concern for estimation of population quantities, it is even more necessary to pay attention to them in a small area estimation (SAE) context, where sample size is usually very small and the estimation in often model based. In this paper we set two goals: The first is to review recent developments in outlier robust SAE. In particular, we focus on the use of partial bias corrections when outlier robust fitted values under a working model generate biased predictions from sample data containing representative outliers. Then we propose an outlier robust bootstrap MSE estimator for M-quantile based small area predictors which considers a bounded-block-bootstrap approach. We illustrate these methods through model based and design based simulations and in the context of a particular survey data set that has many of the outlier characteristics that are observed in business surveys. [ABSTRACT FROM AUTHOR]

In thermal explosions of the nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)- based explosives LX-10 and PBX-9501, the pre-ignition spatial and temporal heating profile defines the ignition location. The ignition location then determines the extent of inertial confinement and the violence of the resulting deflagration. In this work, we present results of experiments in which ~23 g cylinders of LX-10 and PBX 9501 in thin-walled aluminum confinement vessels were subjected to identical heating profiles but which presented starkly different energy release signatures. Post-explosion LX-10 containment vessels were completely fragmented, while the PBX 9501 vessels were merely ruptured. Flash x-ray radiography images show that the initiation location for the LX-10 is a few mm farther from the end caps of the vessel relative to the initiation location of PBX 9501. This difference increases deflagration confinement for LX-10 at the time of ignition and extends the pressurization time during which the deflagration front propagates in the explosive. The variation in the initiation location, in turn, is determined by the thermal boundary conditions, which differ for these two explosives because of the larger coefficient of thermal expansion and greater thermal stability of the Viton binder in LX-10 relative to the estane and bis(2,2- dinitropropyl) acetal/formal binder of the PBX 9501. The thermal profile and initiation location were modeled for LX-10 using the hydrodynamics and structures code ALE3D; results indicate temperatures in the vicinity of the ignition location in excess of 274 °C near the time of ignition. The conductive burn rates for these two explosives, as determined by flash x-ray radiography, are comparable in the range 0.1-0.2 mm/μs, somewhat faster than rates observed by strand burner experiments for explosives in the temperature range 150-180 °C and pressures up to 100 MPa. The thinnest-wall aluminum containment vessels presented here rupture at lower pressures, in the range 10 MPa, suggesting that moderately higher temperatures and pressures are present near the deflagration front. For these explosives, however the most important property for determining deflagration violence is the degree of inertial confinement. [ABSTRACT FROM AUTHOR]

Data linkage can be used to combine values of the variable of interest from a national survey with values of auxiliary variables obtained from another source, such as a population register, for use in small area estimation. However, linkage errors can induce bias when fitting regression models; moreover, they can create non‐representative outliers in the linked data in addition to the presence of potential representative outliers. In this paper, we adopt a secondary analyst's point of view, assuming that limited information is available on the linkage process, and develop small area estimators based on linear mixed models and M‐quantile models to accommodate linked data containing a mix of both types of outliers. We illustrate the properties of these small area estimators, as well as estimators of their mean squared error, by means of model‐based and design‐based simulation experiments. We further illustrate the proposed methodology by applying it to linked data from the European Survey on Income and Living Conditions and the Italian integrated archive of economic and demographic micro data in order to obtain estimates of the average equivalised income for labour market areas in central Italy. [ABSTRACT FROM AUTHOR]

Introduction: Medical students experience high levels of psychological distress and are at risk for depression, burnout and suicidal ideation. To address these issues, the mindfulnessbased Health Enhancement Program (HEP) forms part of the MBBS (Bachelor of Medicine) at Monash University. This pilot study investigated the relationship between amount of mindfulness practice and measures of mental health, study engagement and dispositional mindfulness. We also sought to understand how "Big Five" personality traits predicted engagement with the intervention. Methods: From an eligible cohort of 322 MBBS students, 37 (24 females, 13 males; aged 17 to 20) provided pre- and post-intervention responses. Participants completed the International Personality Item Pool (IPIP-100) pre-intervention and the Freiburg Mindfulness Inventory (FMI), Depression and Anxiety Scale Stress Scale (DASS-21) and the student version of the Utrecht Work Engagement Scale (UWES-S) pre- and post-intervention. Evaluation: Results indicated that both dispositional mindfulness and study engagement increased from pre- to post-intervention. Results also indicated no increase in depression, anxiety and stress from mid-semester to exam periods. Amount of mindfulness meditation was positively related to agreeableness. Conclusions: These results suggest that individuals who score higher in agreeableness may engage most with mindfulness programs, which may be protective for mental health. However, the conclusions of the study are limited by a small sample size and lack of control group. [ABSTRACT FROM AUTHOR]

A response by author R. J. Chambers to a review by D. Anderson and R. Leftwich of his book "Securities and Obscurities: A Case for Reform of the Law of Company Accounts," is presented.

My paper was prompted by deviations in the state of the art of accounting from ideals espoused by individual accountants and professional bodies. Professor Benston's defense or advocacy of traditional practice disregards those deviations. He disregards the facts that up-to-date prices alone provide serviceable data for the calculation of solvency, debt to equity and asset composition ratios and rates of return, and that only money equivalents or resale prices of assets at a given date can properly be added to derive the asset components of those ratios. Benston contends that traditional accounting may be upheld against exit price accounting on the grounds of its transactions basis, of its longevity, of its cost-benefit relationship, and of its free and willing acceptance by managers and other parties. There are serious defects in each of these lines of argument; and other critical observations on the use of selling price valuations will not withstand scrutiny. Only the acknowledgment of the flaws in present practice and the pursuit of ideals avowed by the profession will rid its practice of absurdities. [ABSTRACT FROM AUTHOR]

To commerce and to finance there can be great service given by accountancy. Its power, though, will not be fully known while bits and pieces stand apart, alone. To teach, to practice, to research, invent, is how the time of many has been spent. But cost of time and effort has been vain; for doubt, dispute, confusion still remain. A better prospect far there is in reach. If those who practice and research and teach were disciplined in such a way that each acknowledged that a common course of thought relates, for all men, to things sold and bought--Accounting, then, might do the job it ought. [ABSTRACT FROM AUTHOR]

Copyright of Contemporary Accounting Research is the property of Canadian Academic Accounting Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article reports on price variation accounting and the paper "Price-Level Changes and Useless Information" by Russell Mathews. The definition of income can be divided by the macroeconomic and microeconomic points of view. In macroeconomics the concept of income can be defined as restricted to the increment in wealth resulting from productive activities which are represented in actual transactions. However, in microeconomics this is not the case. A firm, borrowing money and repaying it during a period where purchasing power is lower than when it borrowed, is better off.

This article discusses the price level problems of capital goods. The author has written the article in response to comments made by R. L. Mathews' article, "Price Level Changes and Useless Information," published in a previous issue. A simplified, four-item balance sheet featuring a transactionless interval and a change only in the general level of prices is presented. "Accounting Research Study No. 6" is discussed. The assumptions of Edgar O. Edwards and Philip W. Bell, who selected opportunity cost and current cost as the base for non-monetary asset accounting, are also discussed.

The article presents an extension of earlier works discussed in "Towards a General Theory of Accounting" and "The Resolution of Some Paradoxes in Accounting." The article adopts the position that accounting is only concerned with the past and present, but presented in a way that remains relevant to the future. The article considers the question of measurement in accounting. The definition of accounting is presented and clarified. The author looks at the monetary and financial aspects associated with choice. Variables to consider regarding the act of valuation are discussed. The author also discussed the accuracy and relevance of accounting measurements.

Abnormalities in brain white matter (WM) structure have been reported in youths having a family history of substance use disorders (SUDs). It was hypothesized that these abnormalities constitute features of the liability for SUDs transmitted across generations. The association between severity of intergenerational risk for SUD, measured by the Transmissible Liability Index (TLI), and white matter microstructure was examined. Diffusion tensor imaging (DTI) measured WM microstructure in forty-four drug-naïve 10-14 year-olds (N = 19 with parental SUD). Metrics of WM microstructure (i.e., fractional anisotropy, radial diffusivity, mean diffusivity and axial diffusivity) were quantified across the whole brain and in four tracts of interest: anterior corona radiata, superior and inferior longitudinal fasciculi and superior fronto-occipital fasciculi. The TLI was completed by the youths, their parents and, when available, their teachers. The relationship between WM structure and TLI score across the entire group was evaluated using linear multiple regression and between group comparisons were also examined. Fractional anisotropy and radial diffusivity in multiple tracts across the brain were significantly associated with TLI scores. Confirming and extending prior research, the findings indicate that global atypicality in WM tracts was linearly related to liability for eventual SUD development in drug naïve youths. [ABSTRACT FROM AUTHOR]

Interpersonal attachment and drug addiction share many attributes across their behavioral and neurobiological domains. Understanding the overlapping brain circuitry of attachment formation and addiction illuminates a deeper understanding of the pathogenesis of trauma-related mental illnesses and comorbid substance use disorders, and the extent to which ending an addiction is complicated by being a sort of mourning process. Attention to the process of addiction recovery-as a form of grieving-in which Kubler-Ross's stages of grief and Prochaska's stages of change are ultimately describing complementary viewpoints on a general process of neural network and attachment remodeling, could lead to more effective and integrative psychotherapy and medication strategies. [ABSTRACT FROM AUTHOR]

Atlantic tomcod in the Hudson River Estuary bioaccumulate high hepatic burdens of environmental toxicants. Previously, we demonstrated that Hudson River tomcod developed resistance to TCDD and PCB toxicity probably through strong natural selection during their early life-stages for a variant of the Aryl Hydrocarbon Receptor2 (AHR2). Here, we evaluated the genomic consequences of the resistant genotype by comparing global gene expression in larval tomcod from the Hudson River with expression in larvae from a nearby sensitive population (Shinnecock Bay). We developed an annotated draft tomcod genome to explore the effects of multigenerational exposure to toxicants and a functionally impaired AHR2 on the transcriptome. We used the tomcod genome as a reference in RNA-Seq to compare global gene expression in tomcod larvae from the Hudson River and Shinnecock Bay after experimental exposure of larvae to graded doses of TCDD. We found dramatic differences between offspring from the two populations in the number of genes that were differentially expressed at all doses (0.01, 0.1, and 1 ppb) and even in the vehicle controls. At the two lowest TCDD doses, 250 and 1,141 genes were differentially expressed in Shinnecock Bay larvae compared with 14 and 12, respectively, in Hudson River larvae. At the highest dose (1.0 ppb), 934 genes were differentially expressed in Shinnecock Bay larvae and 173 in Hudson River larvae, but only 28 (16%) of affected genes were shared among both populations. Given the large difference between the two populations in the number and identity of differentially expressed genes, it is likely that the AHR2 pathway interacts directly or indirectly with many genes beyond those known in the AHR2 battery and that other regulatory systems may also respond to TCDD exposure. The effects of chronic multi-generational exposure to environmental toxicants on the genome of Hudson River tomcod are much greater than previously expected. [ABSTRACT FROM AUTHOR]

Rational: Prefrontal cortical (PFC)-hippocampal-striatal circuits, interconnected via glutamatergic signaling, are dysfunctional in mental illnesses that involve addiction vulnerability. Objectives: In healthy and neurodevelopmentally altered rats, we examined how Radial Arm Maze (RAM) performance estimates addiction vulnerability, and how starting a glutamatergic modulating agent, N-acetyl cysteine (NAC) in adolescence alters adult mental illness and/or addiction phenotypes. Methods: Rats with neonatal ventral hippocampal lesions (NVHL) vs. SHAM-operated controls were randomized to NAC vs. saline in adolescence followed by cognitive testing (RAM) in early adulthood and then cocaine behavioral sensitization (experiment 1; n = 80) or nicotine self-administration (experiment 2; n = 12). Results: In experiment 1, NVHL rats showed over-consumption of food (Froot-Loops (FL)) baiting the RAM with poor working memory (low-arm entries to repeat (ETR)), producing an elevated FL to ETR ratio ('FLETR'; p < 0.001). FLETR was the best linear estimator (compared to FL or ETR) of magnitude of long-term cocaine sensitization ( R = 0.14, p < 0.001). NAC treatment did not alter FL, ETR, FLETR, or cocaine sensitization. In experiment 2, FLETR also significantly and uniquely correlated with subsequent drug seeking during nicotine-induced reinstatement after extinction of nicotine self-administration ( R = 0.47, p < 0.01). NAC did not alter RAM performance, but significantly reversed NVHL-induced increases in nicotine seeking during extinction and reinstatement. Conclusions: These findings demonstrate the utility of animal models of mental illness with addiction vulnerability for developing novel diagnostic measures of PFC-hippocampal-striatal circuit dysfunction that may reflect addiction risk. Such tests may direct pharmacological treatments prior to adulthood and addictive drug exposure, to prevent or treat adult addictions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Fourfold increases in opioid prescribing and dispensations over 2 decades in the U.S. has paralleled increases in opioid addictions and overdoses, requiring new preventative, diagnostic, and treatment strategies. This study examines Prescription Drug Monitoring Program (PDMP) tracking as a novel measure of opioid addiction treatment outcomes in a university-affiliated integrated mental health-addiction treatment clinic.Methods: Repeated measure parametrics examined PDMP and urine drug screening (UDS) data before and after first injection for all patients (N = 68) who received at least one long-acting naltrexone injection (380 mg/IM) according to diagnostic groupings of having either (i) alcohol (control); (ii) opioid; or (iii) combined alcohol and opioid use disorders.Results: There were no group differences post-injection in treatment days, injections delivered, or treatment service encounters. UDS and PDMP measures of opioid exposures were greater in opioid compared to alcohol-only patients. Post-first injection, UDS's positive for opioids declined (p < .05) along with PDMP measures of opioid prescriptions (p < .001), doses (p < .01), types (p < .001), numbers of dispensing prescribers (p < .001) and pharmacies (p < .001). Opioid patients without alcohol disorders showed the best outcomes with 50% to 80% reductions in PDMP-measures of opioids, down to levels of alcohol-only patients.Conclusions: This study shows PDMP utility for measuring opioid addiction treatment outcomes, supporting the routine use of PDMPs in clinical and research settings.Scientific Significance: These findings demonstrate that opioid addiction in patients with complex addictions and mental illnesses comorbidities can show effective treatment responses as measured by PDMP tracking of decreases in opioid prescriptions to those patients. (Am J Addict 2016;25:557-564). [ABSTRACT FROM AUTHOR]

Measures of population productivity and individual survival are essential for effective conservation management and scientific investigations. In studies of birds, individuals are often marked with unique colour band combinations to enable estimates of population vital rates. If birds are banded in the nest this must be done at the correct stage in nestling development. If nestlings are banded too early it can lead to leg damage. If they are banded too late it can cause early fledging and reduced survival. Here, we use photographs to guide estimation of the best stage to band North Island robin (Petroica longipes), or toutouwai, nestlings, which is typically at 9–12 days of age. [ABSTRACT FROM PUBLISHER]

Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) has proven to be a powerful technique revealing complexity and diversity of natural DOM molecules, but its application to DOM analysis in grazing-impacted agricultural systems remains scarce. In the present study, we presented a case study of using ESI-FTICR-MS in analyzing DOM from four headwater streams draining forest- or pasture-dominated watersheds in Virginia, USA. In all samples, most formulas were CHO compounds (71.8–87.9%), with other molecular series (CHOS, CHON, CHONS, and CHOP (N, S)) accounting for only minor fractions. All samples were dominated by molecules falling in the lignin-like region (H/C = 0.7–1.5, O/C = 0.1–0.67), suggesting the predominance of allochthonous, terrestrial plant-derived DOM. Relative to the two pasture streams, DOM formulas in the two forest streams were more similar, based on Jaccard similarity coefficients and nonmetric multidimensional scaling calculated from Bray-Curtis distance. Formulas from the pasture streams were characterized by lower proportions of aromatic formulas and lower unsaturation, suggesting that the allochthonous versus autochthonous contributions of organic matter to streams were modified by pasture land use. The number of condensed aromatic structures (CAS) was higher for the forest streams, which is possibly due to the controlled burning in the forest-dominated watersheds and suggests that black carbon was mobilized from soils to streams. During 15-day biodegradation experiments, DOM from the two pasture streams was altered to a greater extent than DOM from the forest streams, with formulas with H/C and O/C ranges similar to protein (H/C = 1.5–2.2, O/C = 0.3–0.67), lipid (H/C = 1.5–2.0, O/C = 0–0.3), and unsaturated hydrocarbon (H/C = 0.7–1.5, O/C = 0–0.1) being the most bioreactive groups. Aromatic compound formulas including CAS were preferentially removed during combined light+bacterial incubations, supporting the contention that black carbon is labile to light alterations. Collectively, our data demonstrate that headwater DOM composition contains integrative information on watershed sources and processes, and the application of ESI-FTICR-MS technique offers additional insights into compound composition and reactivity unrevealed by fluorescence and stable carbon isotopic measurements. [ABSTRACT FROM AUTHOR]

New England coastal and adjacent Nova Scotia shelf waters have a reduced buffering capacity because of significant freshwater input, making the region's waters potentially more vulnerable to coastal acidification. Nutrient loading and heavy precipitation events further acidify the region's poorly buffered coastal waters. Despite the apparent vulnerability of these waters, and fisheries' and mariculture's significant dependence on calcifying species, the community lacks the ability to confidently predict how the region's ecosystems will respond to continued ocean and coastal acidification. Here, we discuss ocean and coastal acidification processes specific to New England coastal and Nova Scotia shelf waters and review current understanding of the biological consequences most relevant to the region. We also identify key research and monitoring needs to be addressed and highlight existing capacities that should be leveraged to advance a regional understanding of ocean and coastal acidification. [ABSTRACT FROM AUTHOR]

Rational: Nicotine use in schizophrenia has traditionally been explained as 'self-medication' of cognitive and/or nicotinic acetylcholinergic receptor (nAChR) abnormalities. Objectives: We test this hypothesis in a neurodevelopmental rat model of schizophrenia that shows increased addiction behaviors including enhanced nicotine reinforcement and drug-seeking. Methods: Nicotine transdermal patch (5 mg/kg/day vs. placebo × 10 days in adolescence or adulthood) effects on subsequent radial-arm maze learning (15 sessions) and frontal-cortical-striatal nAChR densities (αβ; [3H]-epibatidine binding) were examined in neonatal ventral hippocampal lesion (NVHL) and SHAM-operated rats. Results: NVHL cognitive deficits were not differentially affected by nicotine history compared to SHAMs. Nicotine history produced minimal cognitive effects while increasing food-reward consumption on the maze, compounding with NVHL-induced overconsumption. Acute nicotine (0.5 mg/kg) delivered before the final maze sessions produced modest improvements in maze performance in rats with nicotine patch histories only, but not differentially so in NVHLs. Consistent with in vivo neuroimaging of β nAChR binding in schizophrenia smokers vs. non-smokers and healthy controls, adult NVHLs showed 12% reductions in nAChR binding in MPFC ( p < 0.05) but not ventral striatum (<5% changes, p > .40), whereas nicotine history elevated nAChRs across both regions (>30%, p < 0.001) without interacting with NVHLs. Adolescent vs. adult nicotine exposure did not alter nAChRs differentially. Conclusions: Although replicating nicotine-induced upregulation of nAChRs in human smokers and demonstrating NVHL validity in terms of schizophrenia-associated nAChR density patterns, these findings do not support hypotheses explaining increased nicotine use in schizophrenia as reflecting illness-specific effects of nicotine to therapeutically alter cognition or nAChR densities. [ABSTRACT FROM AUTHOR]

This study developed and applied an approach to calculate the proportion of fish gut content composed of mucus secreted by the oropharyngeal cavity and gut. The amount of nitrogen in the contents of the foregut (oesophagus and gizzard) and the epibranchial organs of suspension-feeding American gizzard shad Dorosoma cepedianum was significantly higher than the nitrogen in the homogeneous food source. Using data collected from suspension-feeding experiments and the nitrogen content of D. cepedianum mucus, a series of equations illustrated that mucus constituted c. 10% of D. cepedianum foregut content and 12% of epibranchial organ content by dry mass. Future quantification of fish feeding selectivity and absorption efficiency can use this approach to take into account the contribution of fish mucus to the nutrients in the gut contents. This study supports the conclusion that suspension-feeding D. cepedianum in a heterogeneous environment selectively ingest nutrient-rich particles, even when gut nutrient content is adjusted to take into account the contribution of mucus. [ABSTRACT FROM AUTHOR]