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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]

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]

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]

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]

Percutaneous embolization of the bronchial arteries to control massive or recurrent hemoptysis has become an accepted procedure, especially in treating patients with chronic pulmonary disease who are poor candidates for lung resection. Nonbronchial systemic collateral arteries and pulmonary arteries may contribute significantly to pulmonary hemorrhage, but embolization of these vessels has not been stressed in recent literature. When embolization of the bronchial artery fails to control hemoptysis, nonbronchial systemic collateral arteries should be embolized. If no systemic collaterals are present, then embolization of segmental pulmonary arteries may prove helpful. [ABSTRACT FROM AUTHOR]

Suspended particulate organic matter (POM) in headwater streams is an important source of food and energy to stream food webs. In order to determine the effects of watershed land use on the sources and characteristics of POM, we compared the lipid composition of POM (fatty acid, aliphatic alcohol and sterol) from streams influenced by different types of watershed land use. Eight first-order streams discharging to the York River Estuary (Virginia, USA) were sampled during baseflow conditions bi-monthly from February to November 2009, including streams draining forest-dominated, pasture-dominated, cropland-dominated, and urban land-dominated watersheds. Allochthonous vs. autochthonous lipids showed that POM in most of these streams was dominated by allochthonous sources (59.5 ± 14.2 vs. 39.6 ± 14.5 % for aliphatic alcohols and 52.9 ± 11.5 vs. 34.1 ± 10.3 % for sterols). The relative abundance of allochthonous vs. autochthonous lipid inputs to POM varied as a function of land use type. POM in streams draining forest-dominated watersheds contained a higher proportion of allochthonous lipids and a lower proportion of autochthonous lipids than the streams influenced by human land use. The contribution of bacterial fatty acids differed significantly among sampling times ( P = 0.003), but not among land use types ( P = 0.547). Stepwise linear regression model selected nitrate and temperature as the best predictors of variation in bacterial inputs to POM. Proxies used to assess the nutritional value of POM potentially available to stream consumers included C:N ratios, and the concentrations of total long-chain polyunsaturated fatty acids, eicosapentaenoic acid, arachidonic acid, and cholesterol. None of these nutritional proxies differed among sampling months ( P ≥ 0.171), but the proxies showed that the nutritional value of POM in forest streams was lower than in urban streams. Collectively, these findings suggest that human land use in upstream watersheds alters the source composition and nutritional value of stream POM, which not only impacts food quality for stream biota, but also potentially changes the characteristics of OM reaching downstream ecosystems. [ABSTRACT FROM AUTHOR]

We examined interannual variation in soil properties from wetlands occurring in adjacent drainage basins from the southeastern Everglades. Triplicate 10-cm soil cores were collected, homogenized, and analyzed during the wet season 2006–2010 from five freshwater sawgrass wetland marshes and three estuarine mangrove forests. Soil bulk density from the Taylor Slough basin ranged from 0.15 gm-cm−3 to 0.5 gm-cm−3, was higher than from the Panhandle basin every year, and generally increased throughout the study period. Organic matter as a percent loss on ignition ranged from 7 % to 12 % from freshwater marshes and from 13 % to 56 % from estuarine mangroves. Extractable iron in soils was similar among drainage basins and wetland types, typically ranging from 0.6 to 2.0 g Fe kg−1. In contrast, inorganic sulfur was on average over four times higher from estuarine soils relative to freshwater, and was positively correlated with soil organic matter. Finally total soil phosphorus (P) was lower in freshwater soils relative to estuarine soils (84 ± 5 versus 326 ± 32 mg P kg−1). Total P from the freshwater marshes in the Panhandle basin rose throughout the study period from 54.7 ± 8.4 to 107 ± 17 mg P kg−1, a possible outcome of differences in water management between drainage basins. [ABSTRACT FROM AUTHOR]

The amounts, sources and relative ages of inorganic and organic carbon pools were assessed in eight headwater streams draining watersheds dominated by either forest, pasture, cropland or urban development in the lower Chesapeake Bay region (Virginia, USA). Streams were sampled at baseflow conditions six different times over 1 year. The sources and ages of the carbon pools were characterized by isotopic (δC and ∆C) analyses and excitation emission matrix fluorescence with parallel factor analysis (EEM-PARAFAC). The findings from this study showed that human land use may alter aquatic carbon cycling in three primary ways. First, human land use affects the sources and ages of DIC by controlling different rates of weathering and erosion. Relative to dissolved inorganic carbon (DIC) in forested streams which originated primarily from respiration of young, C-enriched organic matter (OM; δC = −22.2 ± 3 ‰; ∆C = 69 ± 14 ‰), DIC in urbanized streams was influenced more by sedimentary carbonate weathering (δC = −12.4 ± 1 ‰; ∆C = −270 ± 37 ‰) and one of pasture streams showed a greater influence from young soil carbonates (δC = −5.7 ± 2.5 ‰; ∆C = 69 ‰). Second, human land use alters the proportions of terrestrial versus autochthonous/microbial sources of stream water OM. Fluorescence properties of dissolved OM (DOM) and the C:N of particulate OM (POM) suggested that streams draining human-altered watersheds contained greater relative contributions of DOM and POM from autochthonous/microbial sources than forested streams. Third, human land uses can mobilize geologically aged inorganic carbon and enable its participation in contemporary carbon cycling. Aged DOM (∆C = −248 to −202 ‰, equivalentC ages of 1,811-2,284 years BP) and POM (∆C = −90 to −88 ‰, C ages of 669-887 years BP) were observed exclusively in urbanized streams, presumably a result of autotrophic fixation of aged DIC (−297 to −244 ‰, C age = 2,251-2,833 years BP) from sedimentary shell dissolution and perhaps also watershed export of fossil fuel carbon. This study demonstrates that human land use may have significant impacts on the amounts, sources, ages and cycling of carbon in headwater streams and their associated watersheds. [ABSTRACT FROM AUTHOR]

There is a critical need to develop novel pharmacotherapeutics capable of addressing the positive, negative, and cognitive symptoms of schizophrenia. Building on recent studies with a racemic mixture of the synthetic tetrahydroprotoberberine, D,L-Govadine, we isolated the D- and L-stereoisomers and employed a battery of behavioral, neurochemical, and electrophysiological procedures to assess their individual therapeutic potential. Rodent models predictive of antipsychotic efficacy and those that model positive symptoms were employed and we found that L-Govadine, but not D-Govadine, improved these measures. Pretreatment with either stereoisomer during CS pre-exposure prevented the disruption of latent inhibition by amphetamine. Moreover, pretreatment with either stereoisomer also improved deficits in social interaction in the neonatal ventral hippocampal lesioned rat. Improved cognitive performance in two different prefrontal cortex-dependent tasks was observed with D-, but not L-Govadine, which strongly suggests that the D-steroisomer may be an effective cognitive enhancer. Alterations in dopamine efflux were also assessed and L-Govadine increased dopamine efflux in both the prefrontal cortex and nucleus accumbens. However, D-Govadine only increased dopamine efflux in the prefrontal cortex and not in the nucleus accumbens. Electrophysiological studies confirmed that L-Govadine is a DA-D2 antagonist, whereas D-Govadine shows no appreciable physiological effects at this receptor. Collectively these data show that L-Govadine performs well on measures predictive of antipsychotic efficacy and rodent models of positive symptoms through antagonism of DA-D2 receptors, whereas D-Govadine improves impairments in compromised memory function in delayed response tasks possibly through selective increases in DA efflux in the frontal cortex. [ABSTRACT FROM AUTHOR]

The effective use of spatial information, that is, the geographic locations of population units, in a regression model-based approach to small area estimation is an important practical issue. One approach for incorporating such spatial information in a small area regression model is via Geographically Weighted Regression (GWR). In GWR, the relationship between the outcome variable and the covariates is characterised by local rather than global parameters, where local is defined spatially. In this paper, we investigate GWR-based small area estimation under the M-quantile modelling approach. In particular, we specify an M-quantile GWR model that is a local model for the M-quantiles of the conditional distribution of the outcome variable given the covariates. This model is then used to define a bias-robust predictor of the small area characteristic of interest that also accounts for spatial association in the data. An important spin-off from applying the M-quantile GWR small area model is that it can potentially offer more efficient synthetic estimation for out of sample areas. We demonstrate the usefulness of this framework through both model-based as well as design-based simulations, with the latter based on a realistic survey data set. The paper concludes with an illustrative application that focuses on estimation of average levels of Acid Neutralising Capacity for lakes in the Northeast of the USA. [ABSTRACT FROM AUTHOR]

Objective:To investigate the neural mechanisms of food motivation in children and adolescents, and examine brain activation differences between healthy weight (HW) and obese participants.Subjects:Ten HW children (ages 11-16; BMI < 85%ile) and 10 obese children (ages 10-17; BMI >95%ile) matched for age, gender and years of education.Measurements:Functional magnetic resonance imaging (fMRI) scans were conducted twice: when participants were hungry (pre-meal) and immediately after a standardized meal (post-meal). During the fMRI scans, the participants passively viewed blocked images of food, non-food (animals) and blurred baseline control.Results:Both groups of children showed brain activation to food images in the limbic and paralimbic regions (PFC/OFC). The obese group showed significantly greater activation to food pictures in the PFC (pre-meal) and OFC (post-meal) than the HW group. In addition, the obese group showed less post-meal reduction of activation (vs pre-meal) in the PFC, limbic and the reward-processing regions, including the nucleus accumbens.Conclusion:Limbic and paralimbic activation in high food motivation states was noted in both groups of participants. However, obese children were hyper-responsive to food stimuli as compared with HW children. In addition, unlike HW children, brain activations in response to food stimuli in obese children failed to diminish significantly after eating. This study provides initial evidence that obesity, even among children, is associated with abnormalities in neural networks involved in food motivation, and that the origins of neural circuitry dysfunction associated with obesity may begin early in life. [ABSTRACT FROM AUTHOR]

Background:Differences in behavioral phenotypes between the two most common subtypes of Prader-Willi syndrome (PWS) (chromosome 15q deletions and maternal uniparental disomy 15 (UPD) indicate that distinct neural networks may be affected. Though both subtypes display hyperphagia, the deletion subgroup shows reduced behavioral inhibition around food, whereas those with UPD are generally more able to maintain cognitive control over food intake impulses.Objective:To examine the neural basis of phenotypic differences to better understand relationships between genetic subtypes and behavioral outcomes. We predicted greater food motivation circuitry activity in the deletion subtype and greater activity in higher order cognitive regions in the UPD group, especially after eating.Design and participants:Nine individuals with PWS due to UPD and nine individuals with PWS due to (type 2) deletion, matched for age, gender and body mass index, underwent functional magnetic resonance imaging (fMRI) while viewing food images during two food motivation states: one before (pre-meal) and one after (post-meal) eating a standardized 500 kcal meal.Results:Both PWS subgroups showed greater activity in response to food pre- and post-meal compared with the healthy-weight group. Compared with UPD, the deletion subtype showed increased food motivation network activation both pre- and post-meal, especially in the medial prefrontal cortex (mPFC) and amygdala. In contrast, the UPD group showed greater activation than the deletion subtype post-meal in the dorsolateral prefrontal cortex (DLPFC) and parahippocampal gyrus (PHG).Conclusion:These preliminary findings are the first functional neuroimaging findings to support divergent neural mechanisms associated with behavioral phenotypes in genetic subtypes of PWS. Results are discussed within the framework of genetic mechanisms such as haploinsufficiency and gene dosage effects and their differential influence on deletion and UPD subtypes, respectively.International Journal of Obesity (2009) 33, 273–283; doi:10.1038/ijo.2008.255; published online 2 December 2008 [ABSTRACT FROM AUTHOR]

Current evidence for the use of FDG PET/PET-CT in staging thoracic oesophageal and GOJ cancer is reviewed. PubMed, Medline, Embase (1988–November 2006) and the Cochrane database identifed studies in which FDG PET and PET CT were used for the assessment of thoracic and GOJ cancer. Conventional assessment remains the mainstay for evaluating the primary site. EUS is used for assessing the primary site, but when EUS is incomplete or not tolerated FDG PET CT is invaluable. The major of advantage of FDG PET CT lies in the ability to detect metastatic disease beyond the celiac axis. There is growing evidence to show that FDG PET CT is useful for assessment of treatment response. FDG PET CT will also detect other occult primary cancers. The contribution of FDG PET CT to the investigation of patients with primary thoracic oesophageal and GOJ cancer has resulted in improved staging, so providing the ability to optimise treatment. [ABSTRACT FROM AUTHOR]

Discusses a research on natural reward-related learning in rats with neonatal ventral hippocampal lesions and prior cocaine exposure. Dissolution of concaine hydrochloride; Assessment of reward-conditioned learning; Information on lesion verification.

Characterization of neuronal death and neurogenesis in the adult brain of birds, humans, and other mammals raises the possibility that neuronal turnover represents a special form of neuroplasticity associated with stress responses, cognition, and the pathophysiology and treatment of psychiatric disorders. Multilayer neural network models capable of learning alphabetic character representations via incremental synaptic connection strength changes were used to assess additional learning and memory effects incurred by simulation of coordinated apoptotic and neurogenic events in the middle layer. Using a consistent incremental learning capability across all neurons and experimental conditions, increasing the number of middle layer neurons undergoing turnover increased network learning capacity for new information, and increased forgetting of old information. Simulations also showed that specific patterns of neural turnover based on individual neuronal connection characteristics, or the temporal-spatial pattern of neurons chosen for turnover during new learning impacts new learning performance. These simulations predict that apoptotic and neurogenic events could act together to produce specific learning and memory effects beyond those provided by ongoing mechanisms of connection plasticity in neuronal populations. Regulation of rates as well as patterns of neuronal turnover may serve an important function in tuning the informatic properties of plastic networks according to novel informational demands. Analogous regulation in the hippocampus may provide for adaptive cognitive and emotional responses to novel and stressful contexts, or operate suboptimally as a basis for psychiatric disorders. The implications of these elementary simulations for future biological and neural modeling research on apoptosis and neurogenesis are discussed. [ABSTRACT FROM AUTHOR]

The prevalence of problem and pathological gambling in adolescence and young adulthood has been found to be two- to fourfold higher than in adulthood. Given that these high rates might predict future increases across all age groups, it is important to explore the causes of the elevated rates of problem and pathological gambling among youths. This article reviews evidence for a neurobiological basis for adolescent vulnerability to problem and pathological gambling behaviors. We propose that a common trait motif of impulsivity might underlie phenomenology of pathological gambling, commonly comorbid psychiatric disorders, and related aspects of adolescent behavior. Recent advances in understanding the brain mechanisms involved in motivation, reward, and decision-making allow a discussion of neural circuitry underlying impulsivity. Emerging data indicate that important neurodevelopmental events during adolescence occur in brain regions associated with motivation and impulsive behavior. We hypothesize that immaturity of frontal cortical and subcortical monoaminergic systems during normal neurodevelopment underlies adolescent impulsivity as a transitional trait-behavior. While these neurodevelopmental processes may confer advantage by promoting a learning drive for optimal adaptation to adult roles, they may also confer an increased vulnerability to addictive behaviors such as problem and pathological gambling. An exploration of the developmental changes in neural circuitry involved in impulse control has significant implications for understanding adolescent behaviors and treating problem and pathological gambling among youths. [ABSTRACT FROM AUTHOR]

The high prevalence of substance use disorders in schizophrenia relative to the general population and other psychiatric diagnoses could result from developmental neuropathology in hippocampal and cortical structures that underlie schizophrenia. In this study, we tested the effects of neonatal ventral hippocampal lesions on instrumental behavior reinforced by sucrose pellets and intravenous cocaine injections. Lesioned rats acquired sucrose self-administration faster than sham-lesioned rats, but rates of extinction were not altered. Lesioned rats also responded at higher rates during acquisition of cocaine self-administration, and tended to acquire self-administration faster. Higher response rates reflected perseveration of responding during the post-injection “time-out” periods, and a greater incidence of binge-like cocaine intake, which persisted even after cocaine self-administration stabilized. In contrast to sucrose, extinction from cocaine self-administration was prolonged in lesioned rats, and reinstatement of cocaine seeking induced by cocaine priming increased compared with shams. These results suggest that neonatal ventral hippocampal lesions facilitate instrumental learning for both natural and drug rewards, and reduce inhibitory control over cocaine taking while promoting cocaine seeking and relapse after withdrawal. The findings are discussed in terms of possible developmental or direct effects of the lesions, and both positive reinforcement (substance use vulnerability as a primary disease symptom) and negative reinforcement (self-medication) theories of substance use comorbidity in schizophrenia. [Copyright &y& Elsevier]

Semi-crystalline poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymers are biodegradable systems with potential as substrates for use in tissue regeneration. Previous studies have shown that severe embrittlement occurs on storage at room temperature restricting their application possibilities. Concepts such as secondary, advancing crystallisation causing changes in the amorphous/crystalline ratio have been mooted as the cause of the embrittlement. Using films prepared by extrusion and compression moulding procedures we have attempted to probe not only the pure amorphous and crystalline phases but also the interfacial region. Interpretation of dynamic mechanical and dielectric data highlights the changes in the nature of the interfacial region on processing. Moreover, the use of the Thermally Stimulated Discharge technique is a powerful probe for highlighting the morphological changes induced in multiphase systems by the processing step. [ABSTRACT FROM AUTHOR]

The directional technology distance function is introduced, given an interpretation as a min-max, and compared with other functional representations of the technology including the Shephard input and output distance functions and the McFadden gauge function. A dual correspondence is developed between the directional technology distance function and the profit function, and it is shown that all previous dual correspondences are special cases of this correspondence. We then show how Nerlovian (profit-based) efficiency measures can be computed using the directional technology distance function. [ABSTRACT FROM AUTHOR]

Human sera from patients showing seroconversion following a primary herpes simplex virus type 1 (HSV-1) or HSV type 2 (HSV-2) infection, as well as 19S and 7S fractions obtained from the same sera, have been used for typing 191 HSV isolates by an indirect peroxidase-labeled antibody (PLA) method. Typing has also been performed on all of the isolates using a microneutralization (MN) and the indirect hemagglutination (IHA) inhibition test. Furthermore, 30 isolates have been typed by a plaque method. Results obtained with the PLA method was in complete agreement with those of the other two procedures. The PLA method is rapid and simple, offers easy interpretation and a permanent record of results. [ABSTRACT FROM AUTHOR]

Sixteen cytomegalovirus (CMV) isolates from both ill and healthy patients were identified by the immunoperoxidase technique (IP). CMV detection was accomplished by direct examination of the primary isolate using either direct (DIP) or indirect immunoperoxidase (IIP) techniques. In thirteen of the isolates, confirmation of identification was achieved by indirect immunofluorescence (IFA) and by demonstration of herpes particles by electron microscopy (EM). Further, in four cases of non-CMV alterations in the tissue culture which might be confused with actual infection, the IP test was negative as were the confirmatory tests. The IIP is preferred over the DIP test since the latter shows a certain amount of background stain of uninfected cells. Tissue culture cells showing focal CMV cytopathic effect contained both nuclear and cytoplasmic inclusions stained by IP technique. Nonspecific staining was associated with cytoplasmic inclusion bodies. The IP technique can detect individual cell CMV infection at 24 hours when EM reveals only unenveloped viral particles. It is sensitive, specific, and allows direct identification of infected cells in the primary isolate in as little as 90 minutes. Furthermore, it can be performed in standard isolation tissue culture tubes, whereas IFA requires the transfer of the infected cells onto slides or the routine use of Leighton tubes. [ABSTRACT FROM AUTHOR]

The theory of the Gantmakher effect (the radio-frequency size effect) is outlined, and the information on mean free paths obtained from it is briefly reviewed. [ABSTRACT FROM AUTHOR]

The management of patients with respiratory insufficiency, using intermittent positive pressure, has been discussed in detail Emphasis has been laid on the underlying physiological problems and on the need for detailed specialized knowledge. The available equipment and methods of use are discussed, together with methods of monitoring assisted respiration. Problems of diagnosis of underventilation, general principles of management and the problems associated with the more common causes of respiratory insufficiency are discussed. [ABSTRACT FROM AUTHOR]

40 rats were subjected daily for 6 months to an atmosphere containing 50 ppm MnBK. 32 of the rats presented with demyelination of the sciatic nerve and 2 of these with axonal hypertrophy. [ABSTRACT FROM AUTHOR]

Computed tomography has proved to be the most effective mode of evaluating cerebral infarction in 143 documented cases. This was especially true when multiple focal infarcts were present. The incidence of contrast enhancement in acute infarcts was 88%. Concomitant acute and old infarcts were observed in 20% of cases. In the acute stage of stroke, radionuclide studies are preferable to contrast angiography since the latter may aggravate the pre-existing focal ischemia. Follow-up CT and radionuclide scans were extremely useful in confirming the diagnosis and demonstrating various postifarction sequelae. [ABSTRACT FROM AUTHOR]

Primary lymphoma of the thyroid, although uncommon, is being reported more frequently. Although its relationship to Hashimoto's disease is not known a higher incidence of their coexistence has been reported. Seven cases are reported with literature review. [ABSTRACT FROM AUTHOR]

We report a case of non-Hodgkin's lymphoma with CNS involvement confined to the epidural space causing cranial suture diastasis. Cerebrospinal fluid and bone marrow were normal. Two cases only of cranial epidural lymphoma have been reported in the literature; in both cases, the leptomeninges were also involved but without suture diastasis. [ABSTRACT FROM AUTHOR]

Acute non-cardiogenic pulmonary edema (NCPE) following intravenous administration of contrast media is a rare but life-threatening complication of radiologic contrast material. We recently observed this complication as an idiosyncratic reaction following a coelio-mesenteric arteriography. [ABSTRACT FROM AUTHOR]

Presents an obituary for David Shoenberg, a distinguished scientist who established low-temperature physics as a flourishing discipline in Great Britain before second world war.

Several species of Orius are under investigation in the UK, Europe and North America for the biological control of thrips, especially western flower thrips (Frankliniella occidentalis). The available species are briefly compared and findings on effectiveness and oviposition of O. laevigatus are reported. [ABSTRACT FROM AUTHOR]