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Megaphages, bacteriophages harbouring extremely large genomes, have recently been found to be ubiquitous, being described from a variety of microbiomes ranging from the animal gut to soil and freshwater systems. However, no complete marine megaphage has been identified to date. Here, using both short and long read sequencing, we assembled >900 high-quality draft viral genomes from water in the English Channel. One of these genomes included a novel megaphage, Mar_Mega_1 at >650 Kb, making it one of the largest phage genomes assembled to date. Utilising phylogenetic and network approaches, we found this phage represents a new family of megaphages. Genomic analysis showed Mar_Mega_1 shares relatively few homologues with its closest relatives, but, as with other megaphages Mar_Mega_1 contained a variety of auxiliary metabolic genes responsible for carbon metabolism and nucleotide biosynthesis, including a NADP-dependent isocitrate dehydrogenase [Idh] and nicotinamide-nucleotide amidohydrolase [PncC], which have not previously been identified in megaphages. Mar_Mega_1 was abundant in a marine virome sample and related phages are widely prevalent in the oceans.

The significance of large tropical lakes as environmental reservoirs of Vibrio cholerae in cholera endemic countries has yet to be established. By combining large scale plankton sampling, microbial culture and ultrasensitive molecular methods, namely Droplet Digital PCR (ddPCR) and targeted genomics, the presence of Vibrio cholerae was investigated in a 96,600 L volume of surface water collected on a 322 nautical mile (596 km) transect in Lake Tanganyika. V. cholerae was detected and identified in a large area of the lake. In contrast, toxigenic strains of V. cholerae O1 or O139 were not detected in plankton samples possibly in relation to environmental conditions of the lake ecosystem, namely very low salinity compared to marine brackish and coastal environments. This represents to our knowledge, the largest environmental study to determine the role of tropical lakes as a reservoir of V. cholerae.

This paper describes the development of an MCNP6 model and a suite of supporting MATLAB scripts being developed to conduct detailed studies of the radioactive noble gas background activity concentrations resulting from cosmic-neutron-induced reactions in the Earth’s atmosphere, in various geologies, and in seawater. Initial results generated using the MCNP6 model and the suite of supporting MATLAB scripts indicate that the cosmic-neutron-induced 133Xe background activity concentrations at a depth of 1 m in a geology representative of the Earth’s upper crust and a depth of 5 m in seawater are about 3.48 × 10−1 and 8.49 × 10−7 mBq m−3, respectively.

In recent decades, coral reefs worldwide have undergone significant changes in response to various environmental and anthropogenic impacts. Among the numerous causes of reef degradation, coral disease is one factor that is to a large extent still poorly understood. Here, we characterize the physiology of white patch syndrome (WPS), a disease affecting poritid corals on the Great Barrier Reef. WPS manifests as small, generally discrete patches of tissue discolouration. Physiological analysis revealed that chlorophyll a content was significantly lower in lesions than in healthy tissues, while host protein content remained constant, suggesting that host tissue is not affected by WPS. This was confirmed by transmission electron microscope (TEM) examination, which showed intact host tissue within lesions. TEM also revealed that Symbiodinium cells are lost from the host gastrodermis with no apparent harm caused to the surrounding host tissue. Also present in the electron micrographs were numerous virus-like particles (VLPs), in both coral and Symbiodinium cells. Small (

Porites tissue loss is a common disease of Porites compressa on Hawaiian reefs. Despite its prevalence, to date, the aetiological agent of the disease has not been found. The apparent lack of a microbial causative agent in the similar disease Porites bleaching with tissue loss, as well as increasing evidence of viral infections in scleractinian corals and Symbiodinium, led us to hypothesise that a virus may be responsible. Electron microscopy revealed the presence of numerous and varied virus-like particles (VLPs) in healthy and diseased P. compressa colonies. While overall virus numbers were similar in all samples, the abundance of a group of icosahedral VLPs differed significantly between healthy and diseased colonies. While not conclusive, these results suggest that viruses may play a role in this disease, and provide a basis for further studies.

Neutron activation analysis was used to investigate and quantify the level of heavy metal uptake in the marine environment of Lake Austin in Austin, TX. Specifically, the samples studied were largemouth bass, or micropterus salmoides. The presence of heavy metals in the food chain presents multiple hazards, mostly as a food hazard for those species that ingest the fish, namely humans. To measure the concentrations of heavy metals in various fish samples, the nuclear analytical technique of neutron activation analysis (NAA) was used. Both epithermal and thermal irradiations were conducted for the NAA to look for short and long-lived radioisotopes, respectively. The samples themselves consisted of liver and tissue samples for each of the fish caught. Each sample was freeze-dried and homogenized before irradiation and spectrum acquisition. The results showed that all levels of heavy metals were not sufficient enough to make the fish unsafe for eating, with the highest levels being found for iron and zinc. Gold was found to be at much higher concentrations in the younger fish and virtually non-existent in the larger of the samples.

EhV-86 is a large double stranded DNA virus with a 407,339 base pair circular genome that infects the globally important microalga Emiliania huxleyi. It belongs to a new genus of viruses termed the Coccolithoviridae within the algal virus family Phycodnaviridae. By plotting the EhV-86 genome against itself in a dot-plot analysis we revealed three families of distinctly different repeat sequences throughout its genome, designated Family A, B and C. Family A repeats are non-coding, found immediately upstream of 86 predicted coding sequences (CDSs) and are likely to play a crucial role in controlling the expression of the associated CDSs. Family B repeats are GC rich, coding and correspond to possible calcium binding sites in 22 proline-rich domains found in the protein products of eight predicted EhV-86 CDSs. Family C repeats are AT-rich, non-coding and are likely to form part of the origin of replication. We suggest that these repeat regions are of fundamental importance during virus propagation being involved with transcriptional control (Family A), virus adsorption/release (Family B) and DNA replication (Family C).

In early 2002 coral mortality occurred along 600 km of coastline from Tanzania to Kenya. Astreopora, Echinopora, and Montipora species were severely affected, with Montipora being nearly eliminated from Kenyan reefs. Acropora, Platygyra, Goniopora, and massive Porites were also affected; however, Porites and Goniopora rarely died and often recovered, whereas death for most other species occurred within 2 weeks. In Echinopora and Montipora, a dull ashy tissue color and brittle skeletons characterized the early stages of this event with a mucus layer on the tissue surface in intermediate stages. Mucus and embedded debris then disappeared and surfaces were left covered in a white calcareous dust that sometimes capped a black layer. Astreopora tissues became dull and pale, and seldom produced mucus; eventually the skeleton became bare and white. Either a colorless translucent or brownish thin margin of tissue was visible between living tissue and bare skeleton, depending on species. Scanning electron micrographs of affected corals revealed the presence of fungi. Histology and staining showed that the fungi were mostly in the three genera that died from the syndrome and it may be that fungi invaded and killed corals weakened by another unidentified pathogen.

Water samples from a range of fresh-water Antarctic lakes on Signy Island (South Orkney Islands: 60°45′S, 45 °38′W) were examined for the presence of virus-like particles (VLPs) during the 1998/1999 field season. It was discovered that VLPs were ubiquitous, morphologically diverse and abundant, with high concentrations ranging from 4.9 × 106 ml−1 to 3.1 × 107 ml−1. Likely hosts include bacteria, cyanobacteria and eukaryotic algae. In addition, an unusually large virus morphotype was observed with a head diameter 370 × 330 nm and a tail 1.3 μm long.

Abecarnil is a metabolically stable beta-carboline that binds with high affinity and selectivity to central benzodiazepine receptors. The effects on cognitive and psychomotor skills of abecarnil (ZK 112-119), 2.5 mg and 5.0 mg, were compared with lorazepam 2.0 mg and placebo. Twenty-four healthy, young males participated in a double-blind, four-way Latin square design and performed batteries of behavioral tests at predrug and at 20, 40, 60, 80, 100, 120, 180, 240, 360 and 480 min after drug administration. Abecarnil 5.0 mg and lorazepam 2.0 mg displayed similar impairment profiles in tests of cognitive functions including memory encoding. Abecarnil 2.5 mg was substantially less impairing than lorazepam. Impairment levels of the abecarnil and lorazepam treatments peaked at 2-3 h after oral administration. The two abecarnil doses showed dose-dependent effects on the cognitive and psychomotor tasks. All three drug treatments were well tolerated by the subjects, with no one terminating early due to adverse events. The incidence of reported adverse events for abecarnil was dose-dependent. The most frequent, statistically significant adverse effects were drowsiness, lack of concentration and visual disturbance for abecarnil 5.0 mg; and lack of concentration and dizziness for lorazepam 2.0 mg. There were no significant differences in adverse incidence rates between abecarnil 2.5 mg and placebo.

Nearly 90% of schizophrenics smoke cigarettes, considerably higher than the general population's rate of 25%. There is some indication that schizophrenics may smoke as a form of self-medication. Nicotine has a variety of pharmacologic effects that may both counteract some of the cognitive deficits of schizophrenia and counteract some of the adverse side effects of antipsychotic drugs. In the current study, we assessed the interactions of haloperidol and nicotine on cognitive performance of a group of schizophrenics. These patients were in a double-blind study, randomly assigning them to low, moderate, and high dose levels of haloperidol. The subjects, all smokers, came to the laboratory on four different mornings after overnight deprivation from cigarettes. In a double-blind fashion, they were administered placebo, low (7 mg/day), medium (14 mg/day), or high (21 mg/day) dose nicotine skin patches. Three hours after administration of the skin patch, the subjects were given a computerized cognitive test battery including: simple reaction time, complex reaction time (spatial rotation), delayed matching to sample, the Sternberg memory test, and the Conners continuous performance test (CPT). With the placebo nicotine patch, there was a haloperidol dose-related impairment in delayed matching to sample choice accuracy and an increase in response time on the complex reaction time task. Nicotine caused a dose-related reversal of the haloperidol-induced impairments in memory performance and complex reaction time. In the CPT, nicotine reduced the variability in response that is associated with attentional deficit. These results demonstrate the effects of nicotine in reversing some of the adverse side effects of haloperidol and improving cognitive performance in schizophrenia.

State hospitals provide essential services to many of society's most ill and needy individuals. As the next century approaches, state hospitals can best fulfil their missions by developing as high-quality neuropsychiatric/rehabilitation institutes, as opposed to custodial care centers. Highly skilled professionals whose education has included the special knowledge and skill pertinent to state hospitals are central to this development. Although “training units” in state hospitals have existed in many locales, a specific curriculum is often lacking. This article describes the curriculum for psychiatric residents who rotate through the Professional Education Unit at Dammasch State Hospital, as part of the Oregon Public Psychiatry Training Program. The curriculum is described by exploration of the individual learning contract, known as the “Educational Plan,” which guides each resident's work.

Training has been a longstanding and fruitful area of collaboration between the public and academic sectors. Graduate medical education for psychiatry residents is one example. This paper reviews the history of Oregon's public psychiatry training program and highlights factors contributing to its success.

This double-blind placebo controlled, parallel design clinical trial compared the therapeutic effects of the addition of lithium or placebo to haloperidol in 21 seriously ill state hospital patients with DSM-III-R schizophrenia, who did not have concurrent affective disorders and who had not responded to previous trials of conventional antipsychotic medication. During a baseline period of 6 weeks, patients were switched to a stable dose of haloperidol (mean +/- SD dose = 13.6 +/- 8.1 mg/day). Patients were then randomized to receive either lithium or placebo in addition to haloperidol for 8 weeks (mean +/- SD lithium level = 0.98 +/- 0.13 mEq/l). Symptoms and side effects were assessed weekly. Improvement in symptoms correlated with the non-blind adjustment of antipsychotic dose, but not with lithium or placebo treatment. Side effects ratings did not differ between the two groups, but one patient developed a reversible delirium associated with combined lithium/haloperidol treatment. For these long-term, severely ill patients, combined treatment afforded no advantage over treatment with haloperidol alone.

In 1989, the Public Psychiatry Training Program of the Oregon Health Sciences University Department of Psychiatry and Dammasch State Hospital opened a collaborative Professional Education Unit with the author as Director. This article describes the Unit's structure and programs, as an example of successful state/university collaboration and a possible model for other training programs in public psychiatry.

Comprehensive treatment programs for individuals with schizophrenia usually include a variety of groups, many of which have concrete tasks as a focus: medication management, social skills training, meal preparation, etc. These groups can simultaneously serve more general rehabilitative purposes if leaders apply principles of group leadership which recognize the neuropathological substrate of schizophrenia and which take into account the specific interpersonal characteristics and needs of individuals who have the illness. This paper presents a framework for leading task-oriented groups for individuals with schizophrenia and give examples from a medication group in a psychosocial rehabilitation program.

Background Emiliania huxleyi virus 86 (EhV-86) is the type species of the genus Coccolithovirus within the family Phycodnaviridae. The fully sequenced 407,339 bp genome is predicted to encode 473 protein coding sequences (CDSs) and is the largest Phycodnaviridae sequenced to date. The majority of EhV-86 CDSs exhibit no similarity to proteins in the public databases. Results Proteomic analysis by 1-DE and then LC-MS/MS determined that the virion of EhV-86 is composed of at least 28 proteins, 23 of which are predicted to be membrane proteins. Besides the major capsid protein, putative function can be assigned to 4 other components of the virion: two lectin proteins, a thioredoxin and a serine/threonine protein kinase. Conclusion This study represents the first steps toward the identification of the protein components that make up the EhV-86 virion. Aside from the major capsid protein, whose function in the virion is well known and defined, the nature of the other proteins suggest roles involved with viral budding, caspase activation, signalling, anti-oxidation, virus adsorption and host range determination.

Research in the area of visual selection has consistently demonstrated that viewing time increases with the complexity of the stimuli. A theoretical position has been proposed to account for these findings in terms of stimulus encoding. This position by Nunnally and his associates (e.g., Nunnally & Lemond, 1973) places primary emphasis on the number of meaningful encodable elements as the stimulus variables to account for the effects attributed to complexity. Two experiments were performed to examine these two stimulus variables. Both experiments employed college students in a free-viewing time procedure. The dependent variable was length of viewing time for each of a series of slides. Experiment I manipulated the number of encodable elements in each slide and the homogeneity or heterogeneity of the stimulus elements. Experiment II compared physical complexity with the number of encodable elements in a factorial design. Both experiments found significant support for the number of meaningful encodable elements as an important determiner of visual selection.

Regional cerebral blood flow (CBF), blood pressure, pulse rate, respiratory rate, end-tidal carbon dioxide and mood states were measured before and after IV injections of 15 mg dextroamphetamine sulfate or saline in 22 physically and mentally healthy normal volunteers. Amphetamine administration was associated with significant increases in systolic blood pressure and vigor and decrease in end-tidal carbon dioxide. There were no significant differences between the amphetamine and saline groups on CBF changes. However, there was a non-significant trend towards a post-amphetamine CBF reduction, even after the flow values were corrected for the acute changes in CO2.

Cerebral blood flow (CBF) measurements and mental status examinations were performed before and 30 min after oral administration of 250 mg of caffeine or a placebo given under double-blind conditions, in two groups of patients with schizophrenia. Caffeine produced significant CBF reductions but no changes in the patient's clinical condition.

The production of randomly generated polygons of high complexity is a very time-consuming process with presently available methods. A technique was developed for speeding this process, particularly when producing very complex figures (e.g., polygons with over 40 sides). A portion of this process was computerized to facilitate production further. The procedure was employed to produce polygons with up to 200 sides. The technique proved feasible in practice, and subsequently clear results were obtained with the polygons in research on visual exploratory behavior.

The purpose of this investigation was to examine the effects of a new methodology in the study of acquired meaning. Over a 15-day period, 20 boys and girls in a sixth-grade classroom learned to associate CVC nonsense syllables with classroom activities (e.g., lunch and recess). The syllables were employed as tickets of permission to participate in associated activities. Subsequently, measures were made of the semantic properties acquired by the syllables. The findings demonstrate the feasibility of employing this naturalistic methodology for the study of acquired meaning.