228 research outputs found

    Preliminary studies on the food and feeding habits of Synodontis membraneceus from Ogobiri River, Nigeria

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    The food and feeding habits of Synodontis membraneceus of Ogobiri River of Bayelsa State, Nigeria was studied using 44 male and 51 specimens that were bought from fishers in the study area measuring between 5 and 25 cm total length. The Numerical and the frequency of Occurrence method of analysis were used. For the males, the food items by the numerical method were copepods (168), insects, (118), Cladocera (69), and unidentified items (32). In the female specimens, the food items were Cladocera (286), Insect (216), Copepod (100) and unidentified organisms/materials (65). In the Frequency of Occurrence method for the males, Copepod was still with a total of (48), Cladocera (44), Insects (29) and unidentified (16). For the females, Cladoera (48), Insects were (30) by Copepods (35) and unidentified (19). The Percentage composition of food items by the Numerical method was Cladocera (45.5%), Insects (34.5%), Copepod (12.5%), and unidentified items (7.0%) while the Percentage Frequency of Occurrence was, Cladocera, (30.5%), Insects (30.9%), Copepod (29.6%), and unidentified items (9.0%)

    Theory of periodic swarming of bacteria: application to Proteus mirabilis

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    The periodic swarming of bacteria is one of the simplest examples for pattern formation produced by the self-organized collective behavior of a large number of organisms. In the spectacular colonies of Proteus mirabilis (the most common species exhibiting this type of growth) a series of concentric rings are developed as the bacteria multiply and swarm following a scenario periodically repeating itself. We have developed a theoretical description for this process in order to get a deeper insight into some of the typical processes governing the phenomena in systems of many interacting living units. All of our theoretical results are in excellent quantitative agreement with the complete set of available observations.Comment: 11 pages, 8 figure

    Electron neutrino tagging through tertiary lepton detection

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    We discuss an experimental technique aimed at tagging electron neutrinos in multi-GeV artificial sources on an event-by-event basis. It exploits in a novel manner calorimetric and tracking technologies developed in the framework of the LHC experiments and of rare kaon decay searches. The setup is suited for slow-extraction, moderate power beams and it is based on an instrumented decay tunnel equipped with tagging units that intercept secondary and tertiary leptons from the bulk of undecayed \pi^+ and protons. We show that the taggers are able to reduce the \nue contamination originating from K_e3 decays by about one order of magnitude. Only a limited suppression (~60%) is achieved for \nue produced by the decay-in-flight of muons; for low beam powers, similar performance as for K_e3 can be reached supplementing the tagging system with an instrumented beam dump.Comment: 19 pages, 7 figures; minor changes, version to appear in EPJ

    Vector Correlators in Lattice QCD: methods and applications

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    We discuss the calculation of the leading hadronic vacuum polarization in lattice QCD. Exploiting the excellent quality of the compiled experimental data for the e^+e^- --> hadrons cross-section, we predict the outcome of large-volume lattice calculations at the physical pion mass, and design computational strategies for the lattice to have an impact on important phenomenological quantities such as the leading hadronic contribution to (g-2)mu and the running of the electromagnetic coupling constant. First, the R(s) ratio can be calculated directly on the lattice in the threshold region, and we provide the formulae to do so with twisted boundary conditions. Second, the current correlator projected onto zero spatial momentum, in a Euclidean time interval where it can be calculated accurately, provides a potentially critical test of the experimental R(s) ratio in the region that is most relevant for (g-2)mu. This observation can also be turned around: the vector correlator at intermediate distances can be used to determine the lattice spacing in fm, and we make a concrete proposal in this direction. Finally, we quantify the finite-size effects on the current correlator coming from low-energy two-pion states and provide a general parametrization of the vacuum polarization on the torus.Comment: 16 pages, 9 figure files; corrected a factor 2 in Eq. (7) over the published versio

    An Anglo-Saxon execution cemetery at Walkington Wold, Yorkshire

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    This paper presents a re-evaluation of a cemetery excavated over 30 years ago at Walkington Wold in east Yorkshire. The cemetery is characterized by careless burial on diverse alignments, and by the fact that most of the skeletons did not have associated crania. The cemetery has been variously described as being the result of an early post-Roman massacre, as providing evidence for a ‘Celtic’ head cult or as an Anglo-Saxon execution cemetery. In order to resolve the matter, radiocarbon dates were acquired and a re-examination of the skeletal remains was undertaken. It was confirmed that the cemetery was an Anglo-Saxon execution cemetery, the only known example from northern England, and the site is set into its wider context in the paper

    Aquatic food security:insights into challenges and solutions from an analysis of interactions between fisheries, aquaculture, food safety, human health, fish and human welfare, economy and environment

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    Fisheries and aquaculture production, imports, exports and equitability of distribution determine the supply of aquatic food to people. Aquatic food security is achieved when a food supply is sufficient, safe, sustainable, shockproof and sound: sufficient, to meet needs and preferences of people; safe, to provide nutritional benefit while posing minimal health risks; sustainable, to provide food now and for future generations; shock-proof, to provide resilience to shocks in production systems and supply chains; and sound, to meet legal and ethical standards for welfare of animals, people and environment. Here, we present an integrated assessment of these elements of the aquatic food system in the United Kingdom, a system linked to dynamic global networks of producers, processors and markets. Our assessment addresses sufficiency of supply from aquaculture, fisheries and trade; safety of supply given biological, chemical and radiation hazards; social, economic and environmental sustainability of production systems and supply chains; system resilience to social, economic and environmental shocks; welfare of fish, people and environment; and the authenticity of food. Conventionally, these aspects of the food system are not assessed collectively, so information supporting our assessment is widely dispersed. Our assessment reveals trade-offs and challenges in the food system that are easily overlooked in sectoral analyses of fisheries, aquaculture, health, medicine, human and fish welfare, safety and environment. We highlight potential benefits of an integrated, systematic and ongoing process to assess security of the aquatic food system and to predict impacts of social, economic and environmental change on food supply and demand

    Clinician-rated quality of video otoscopy recordings and still images for the asynchronous assessment of middle-ear disease

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    INTRODUCTION : Video otoscopy plays an important role in improving access to ear health services. This study investigated the clinician-rated quality of video otoscopy recordings and still images, and compared their suitability for asynchronous diagnosis of middle-ear disease. METHODS : Two hundred and eighty video otoscopy image–recording pairs were collected from 150 children (aged six months to 15 years) by an ear, nose, and throat (ENT) specialist, audiologists, and trained research assistants, and independently rated by an audiologist and ENT surgeon. On a five-point scale, clinicians rated the cerumen amount, field of view, quality, focus, light, and gave an overall rating, and asked whether they could make an accurate diagnosis for both still images and recordings. RESULTS : More video otoscopy recordings were rated as ‘good’ or ‘excellent’ compared to still images across all domains. The mean difference between the two otoscopic procedures ratings was significant across almost all domains (p < 0.05), except ‘cerumen amount’. The suitability to make a diagnosis significantly improved when using recordings (p<0.05). Younger participant age was found to have a significant, negative impact on the ratings across all domains (p < 0.03). The role of the tester conducting video otoscopy did not have a significant impact on the ratings. DISCUSSION : Video otoscopy recordings were found to provide clearer views of the tympanic membrane and increase the ability to make diagnoses, compared to still images, for both audiologists and ENT surgeons. Research assistants with limited practice were able to obtain video otoscopy images and recordings that were comparable to the ones obtained by clinicians.The Telethon Kids Institutehttps://journals.sagepub.com/home/jtthj2022Speech-Language Pathology and Audiolog

    Clinician-rated quality of video otoscopy recordings and still images for the asynchronous assessment of middle-ear disease

    Get PDF
    INTRODUCTION : Video otoscopy plays an important role in improving access to ear health services. This study investigated the clinician-rated quality of video otoscopy recordings and still images, and compared their suitability for asynchronous diagnosis of middle-ear disease. METHODS : Two hundred and eighty video otoscopy image–recording pairs were collected from 150 children (aged six months to 15 years) by an ear, nose, and throat (ENT) specialist, audiologists, and trained research assistants, and independently rated by an audiologist and ENT surgeon. On a five-point scale, clinicians rated the cerumen amount, field of view, quality, focus, light, and gave an overall rating, and asked whether they could make an accurate diagnosis for both still images and recordings. RESULTS : More video otoscopy recordings were rated as ‘good’ or ‘excellent’ compared to still images across all domains. The mean difference between the two otoscopic procedures ratings was significant across almost all domains (p < 0.05), except ‘cerumen amount’. The suitability to make a diagnosis significantly improved when using recordings (p<0.05). Younger participant age was found to have a significant, negative impact on the ratings across all domains (p < 0.03). The role of the tester conducting video otoscopy did not have a significant impact on the ratings. DISCUSSION : Video otoscopy recordings were found to provide clearer views of the tympanic membrane and increase the ability to make diagnoses, compared to still images, for both audiologists and ENT surgeons. Research assistants with limited practice were able to obtain video otoscopy images and recordings that were comparable to the ones obtained by clinicians.The Telethon Kids Institutehttps://journals.sagepub.com/home/jtthj2022Speech-Language Pathology and Audiolog

    Recognize fish as food in policy discourse and development funding

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    The international development community is off-track from meeting targets for alleviating global malnutrition. Meanwhile, there is growing consensus across scientific disciplines that fish plays a crucial role in food and nutrition security. However, this ‘fish as food’ perspective has yet to translate into policy and development funding priorities. We argue that the traditional framing of fish as a natural resource emphasizes economic development and biodiversity conservation objectives, whereas situating fish within a food systems perspective can lead to innovative policies and investments that promote nutrition-sensitive and socially equitable capture fisheries and aquaculture. This paper highlights four pillars of research needs and policy directions toward this end. Ultimately, recognizing and working to enhance the role of fish in alleviating hunger and malnutrition can provide an additional long-term development incentive, beyond revenue generation and biodiversity conservation, for governments, international development organizations, and society more broadly to invest in the sustainability of capture fisheries and aquaculture

    Effectiveness of Antipsychotic Drugs in Patients with Chronic Schizophrenia

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    BACKGROUND The relative effectiveness of second-generation (atypical) antipsychotic drugs as compared with that of older agents has been incompletely addressed, though newer agents are currently used far more commonly. We compared a first-generation antipsychotic, perphenazine, with several newer drugs in a double-blind study. METHODS A total of 1493 patients with schizophrenia were recruited at 57 U.S. sites and randomly assigned to receive olanzapine (7.5 to 30 mg per day), perphenazine (8 to 32 mg per day), quetiapine (200 to 800 mg per day), or risperidone (1.5 to 6.0 mg per day) for up to 18 months. Ziprasidone (40 to 160 mg per day) was included after its approval by the Food and Drug Administration. The primary aim was to delineate differences in the overall effectiveness of these five treatments. RESULTS Overall, 74 percent of patients discontinued the study medication before 18 months (1061 of the 1432 patients who received at least one dose): 64 percent of those assigned to olanzapine, 75 percent of those assigned to perphenazine, 82 percent of those assigned to quetiapine, 74 percent of those assigned to risperidone, and 79 percent of those assigned to ziprasidone. The time to the discontinuation of treatment for any cause was significantly longer in the olanzapine group than in the quetiapine (P<0.001) or risperidone (P=0.002) group, but not in the perphenazine (P=0.021) or ziprasidone (P=0.028) group. The times to discontinuation because of intolerable side effects were similar among the groups, but the rates differed (P=0.04); olanzapine was associated with more discontinuation for weight gain or metabolic effects, and perphenazine was associated with more discontinuation for extrapyramidal effects. CONCLUSIONS The majority of patients in each group discontinued their assigned treatment owing to inefficacy or intolerable side effects or for other reasons. Olanzapine was the most effective in terms of the rates of discontinuation, and the efficacy of the conventional antipsychotic agent perphenazine appeared similar to that of quetiapine, risperidone, and ziprasidone. Olanzapine was associated with greater weight gain and increases in measures of glucose and lipid metabolism
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