312 research outputs found

    Combination of an electrolytic pretreatment unit with secondary water reclamation processes

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    The design and fabrication of a flight concept prototype electrolytic pretreatment unit (EPU) and of a contractor-furnished air evaporation unit (AEU) are described. The integrated EPU and AEU potable water recovery system is referred to as the Electrovap and is capable of processing the urine and flush water of a six-man crew. Results of a five-day performance verification test of the Electrovap system are presented and plans are included for the extended testing of the Electrovap to produce data applicable to the combination of electrolytic pretreatment with most final potable water recovery systems. Plans are also presented for a program to define the design requirements for combining the electrolytic pretreatment unit with a reverse osmosis final processing unit

    Field-induced suppression of the pi-band superconductivity and magnetic hysteresis in the microwave surface resistance of MgB_2 at temperatures near T_c

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    We report on the magnetic-field-induced variations of the microwave surface resistance, R_s, in a polycrystalline MgB_2 sample, at different values of temperature. We have detected a magnetic hysteresis in R_s, which exhibits an unexpected plateau on decreasing the DC magnetic field below a certain value. In particular, at temperatures near T_c the hysteresis manifests itself only through the presence of the plateau. Although we do not quantitatively justify the anomalous shape of the magnetic hysteresis, we show that the results obtained in the reversible region of the R_s(H) curve can be quite well accounted for by supposing that, in this range of magnetic field, the pi-gap is almost suppressed by the applied field and, consequently, all the pi-band charge carriers are quasiparticles. On this hypothesis, we have calculated R_s(H) supposing that fluxons assume a conventional (single core) structure and the flux dynamics can be described in the framework of conventional models. From the fitting of the experimental results, we determine the values of H_{c2}^pi(T) at temperatures near T_c. In our opinion, the most important result of our investigation is that, at least at temperatures near T_c, the value of the applied field that separates the reversible and irreversible regions of the R_s(H) curves is just H_{c2}^pi(T); a qualitative discussion of the possible reason of this finding is given.Comment: 20 pages, 8 embedded figures, 2 Appendices, accepted for publication in Supercond. Sci. Techno

    A survey on knowledge and perceptions regarding head lice on a sample of teachers and students in primary schools of north and south of Italy

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    High rates of pediculosis are found in every part of the world. The age-range most affected is between 3 and 12 years. No-nit policies are ineffective in preventing infestations. On the other hand, misdiagnosis and overuse of pediculicides, increase resistance to treatment. Lack of information leads people to consider this kind of infestation to be associated to low social classes and immigrants. This research has been implemented to find out about the information level on pediculosis on a sample of students (722) and teachers (408) of some primary schools in northern and southern Italy, and to highlight the role of personal aspects such as age, gender, cultural level, geographical position which may influence this topic and, eventually, allow the use of the correct knowledge in developing appropriate procedures within the school district. Data was obtained through a questionnaire containing 21 multiple choice questions for the teachers and 14 for the students. Standard descriptive statistics were computed. ?2 tests were applied to highlight statistical association among observed variables; test for the difference of two proportions were applied to confirm significant differences among the observed proportions. The level of information for students seems to be, approximately, the same both for northern and southern Italy. There was a slight prevalence of correct answers from southern teachers, probably because the phenomenon of pediculosis has a positive trend of growth in the south. The number of correct answers was, for all, on average about 60.0%; a negative result in itself, considering the simplicity of the questions. Knowledge about the biology of the louse was virtually absent. The area of prevention showed lack of information and need for improvement. Most of the teachers believe that there are specific products that can prevent infestation by louse. Most of the teachers have information which does not come from scientific sources. Students receive some short and incomplete information from their parents. Deficiencies in teachers? knowledge indicate that they are inadequately equipped to manage lice infestation. Educational interventions with teachers and families and, as a consequence, with students should be taught at school to allow a correct understanding of the pediculosis, increasing the teachers? competence and, consequently, as soon as the infestation should manifest, a rapid alert of the Health Service so that proper treatment could be provided

    Electromagnetic response of LaO_0.94F_0.06FeAs: AC susceptibility and microwave surface resistance

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    We discuss on the electromagnetic response of a polycrystalline sample of LaO_0.94F_0.06FeAs exposed to DC magnetic fields up to 10 kOe. The low- and high-frequency responses have been investigated by measuring the AC susceptibility at 100 kHz and the microwave surface resistance at 9.6 GHz. At low as well as high DC magnetic fields, the susceptibility strongly depends on the amplitude of the AC driving field, highlighting enhanced nonlinear effects. The field dependence of the AC susceptibility exhibits a magnetic hysteresis that can be justified considering the intragrain-field-penetration effects on the intergrain critical current density. The microwave surface resistance exhibits a clockwise magnetic hysteresis, which cannot be justified in the framework of the critical-state models of the Abrikosov-fluxon lattice; it may have the same origin as that detected in the susceptibility.Comment: 8 pages, 4 embedded eps figures; Proceedings of the 9th EUCAS Conference (Dresden, Germany, September 13-17, 2009

    Share your voice: Online community building during reaffirmation of accreditation

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    Generic University recently underwent a successful reaffirmation of accreditation process with The Higher Learning Commission of the North Central Association of Colleges and Schools. As part of the 3-year process, a committee, named the Education and Communication working group, was formed to inform and engage with the entire Generic community. The aim of this report is to describe the process and strategies this working group employed to achieve those goals in a distance learning environment. The primary charges of the Education and Communication working group were to (1) educate stakeholders about the Higher Learning Commission (HLC), the importance of accreditation, and their role in the accreditation process; (2) provide consistent and quality communication to ensure stakeholders are appropriately informed about HLC and the self-study process; and (3) create and execute an appropriate and supportive communication and education plan during the HLC self-study process. The Education and Communication working group primarily focused on internal stakeholders, including students, faculty, and staff. Additional outreach specifically addressed associated individuals, such as alumni and field site supervisors. Other institutions may define their constituencies differently but will find that the goals, plans, and strategies described here will help them to achieve involvement by their stakeholders in accreditation processes.DOI: 10.18870/hlrc.v3i3.11

    Fluxon dynamics by microwave surface resistance measurements in MgB2

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    Field-induced variations of the microwave surface resistance, Rs(H), have been investigated in high-density ceramic MgB2. At low temperatures, several peculiarities of the Rs(H) curves cannot be justified in the framework of models reported in the literature. We suggest that they are ascribable to the unconventional vortex structure in MgB2, related to the presence of two gaps. On the contrary, the results near Tc can be accounted for by the Coffey and Clem model, with fluxons moving in the flux-flow regime, provided that the anisotropy of the upper critical field is taken into due account.Comment: 6 pages, 4 figure

    Isolation and expression of a novel MBL-like collectin cDNA enhanced by LPS injection in the body wall of the ascidian Ciona intestinalis

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    Collectins are a family of calcium-dependent lectins that are characterized by their collagen-like domains. Considerable interest has been focused on this class of proteins because of their ability to interact with components of the complement system activating a cascade of events responsible for the activation of the innate immune system. A differential screening between LPS-challenged and na\uefve Ciona intestinalis has been performed allowing the isolation of a full length cDNA encoding for a 221 AA protein. In silico analysis has shown that this polypeptide displays protein domains with similarities to mannose-binding lectins. A phylogenetic analysis suggested that C. intestinalis MBL has evolved early as a prototype of vertebrate MBL. Real-time PCR assay demonstrated that this gene is strongly activated after LPS injection in the tunica. In situ hybridization performed in LPS-induced animals has shown that this gene is expressed in granular amoebocytes and large granules hemocytes in the inflamed body wall tissue. Finally, an antimicrobial activity of the C. intestinalis MBL has been demonstrate

    An uncommon presentation of eosinophilic granulomatosis with polyangiitis: a case report

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    INTRODUCTION: Eosinophilic granulomatosis with polyangiitis is a rare and potentially fatal disease if not readily diagnosed. Cerebral involvement is extremely rare and clinical presentation as hemorrhagic stroke is even rarer. CASE PRESENTATION: A 58-year-old Caucasian man was admitted to our medical unit because of a computed tomography-diagnosed hemorrhagic stroke with right-sided hemiparesis and fever. A chest computed tomography scan also revealed multiple bilateral pulmonary infiltrates; coronary artery, and carotid and left vertebral artery calcifications were also observed. Empiric antimicrobial therapy with cephalosporins was promptly undertaken; low-molecular-weight heparin was introduced as prophylaxis for venous thromboembolism. Over the following days, magnetic resonance imaging scans showed a regression of the hemorrhagic framework, also revealing hypoxic areas consistent with acute ischemic lesions. With a computed tomography scan showing a worsening of his pulmonary framework, antimicrobial therapy was modified and corticosteroids were introduced. A new blood cell count revealed further increased leukocytosis (17.49×10(3)μL), characterized by a surprising rise of eosinophilic cells (32.8%). Angiography of the coronary arteries found diffuse dilatations with severe signs of endothelial damage. Such an unexpected framework induced a strong suspicion that the stroke was the expression of a systemic vasculitis, which had triggered his cerebral, coronary, and pulmonary frameworks. The search for antineutrophil cytoplasmic antibody was positive for perinuclear antineutrophil cytoplasmic antibody, and eosinophilic granulomatosis with polyangiitis was diagnosed. Explaining to the patient the rarity of his disease, and what the most typical presentations of eosinophilic granulomatosis with polyangiitis were, he revealed that before admission he had had scalp injuries, in the nuchal region, and had taken corticosteroids as self-medication, with subsequent disappearance of the lesions. Therefore, high-dose corticosteroid treatment was started, and at discharge he was in good clinical condition with a slight right-sided hyposthenia. CONCLUSIONS: A diagnosis of eosinophilic granulomatosis with polyangiitis is often difficult, but we are convinced that intake of corticosteroids on a self-prescribed basis may have obscured the clinical presentation. Therefore, this case also suggests how the growing phenomenon of self-medication can be harmful, and that a careful investigation of clinical history is still an act of paramount importance

    An Analysis of the Neutralizing Antibodies against the Main SARS-CoV-2 Variants in Healthcare Workers (HCWs) Vaccinated against or Infected by SARS-CoV-2

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    : Although the anti-COVID-19 vaccination has proved to be an effective preventive tool, "breakthrough infections" have been documented in patients with complete primary vaccination courses. Most of the SARS-CoV-2 neutralizing antibodies produced after SARS-CoV-2 infection target the spike protein receptor-binding domain which has an important role in facilitating viral entry and the infection of the host cells. SARS-CoV-2 has demonstrated the ability to evolve by accumulating mutations in the spike protein to escape the humoral response of a host. The aim of this study was to compare the titers of neutralizing antibodies (NtAbs) against the variants of SARS-CoV-2 by analyzing the sera of recovered and vaccinated healthcare workers (HCWs). A total of 293 HCWs were enrolled and divided into three cohorts as follows: 91 who had recovered from SARS-CoV-2 infection (nVP); 102 that were vaccinated and became positive after the primary cycle (VP); and 100 that were vaccinated with complete primary cycles and concluded the follow-up period without becoming positive (VN). Higher neutralization titers were observed in the vaccinated subjects' arms compared to the nVP subjects' arms. Differences in neutralization titers between arms for single variants were statistically highly significant (p < 0.001), except for the differences between titers against the Alpha variant in the nVP and in VP groups, which were also statistically significant (p < 0.05). Within the nVP group, the number of subjects with an absence of neutralizing antibodies was high. The presence of higher titers in patients with a complete primary cycle compared to patients who had recovered from infection suggested the better efficacy of artificial immunization compared to natural immunization, and this further encourages the promotion of vaccination even in subjects with previous infections
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