Alien Registration- Lang, Irene L. (Van Buren, Aroostook County)

https://digitalmaine.com/alien_docs/33253/thumbnail.jp

The influence of microstructure on electrical resistivity in palladium alloys

The relationship between microstructure and electrical resistivity has been studied in palladium-tungsten and palladium-molybdenum alloys, which exhibit an anomalous increase in resistivity after annealing. The effect of dislocations and structural order on resistivity has been investigated in order to determine the mechanisms whereby changes in resistivity occur in these alloys. The electrical resistivity of palladium-tungsten and palladium-molybdenum alloys has been determined as a function of annealing temperature, using a sensitive electronic apparatus purpose-designed for the present work. For alloys of low solute concentration a minimum in the electrical resistivity with respect to annealing temperature, which has not previously been reported, was observed. Specimens subjected to annealing experiments have been studied by means of transmission electron microscopy, in order to determine the effect of annealing on microstructure and structural order. The information obtained bas been used to relate the measured changes in electrical resistance and microhardness to the structural evolution of the alloys. It is concluded that the unusual resistance effects observed arise from competition between changing degrees of structural order and dislocation density. Which of these mechanisms predominates under given conditions varies as a function of solute concentration and annealing temperature. In alloys containing more than 6 at.% solute, recovery and recrystallisation processes are accompanied by an increase in resistivity and a decrease in microhardness; after recrystallisation is complete, further annealing bas no significant effect on either property. In alloys containing less than 6 at.% solute, recovery and recrystallisation are accompanied by a decrease in both resistivity and microhardness; but further annealing results in an increase in resistivity. Consideration of this data leads to the conclusion that microbardness is more sensitive to changes in dislocation density than structural order, whereas electrical resistivity is more sensitive to structural order than dislocation density. On this basis it is shown that short-range order increases rapidly at low annealing temperatures in alloys containing more than 6 at.% solute, but slowly in alloys containing less than 6 at.% solute in which short-range order increases rapidly only at higher annealing temperatures

Supernova neutrino physics with xenon dark matter detectors: A timely perspective

Dark matter detectors that utilize liquid xenon have now achieved tonne-scale targets, giving them sensitivity to all flavours of supernova neutrinos via coherent elastic neutrino-nucleus scattering. Considering for the first time a realistic detector model, we simulate the expected supernova neutrino signal for different progenitor masses and nuclear equations of state in existing and upcoming dual-phase liquid xenon experiments. We show that the proportional scintillation signal (S2) of a dual-phase detector allows for a clear observation of the neutrino signal and guarantees a particularly low energy threshold, while the backgrounds are rendered negligible during the supernova burst. XENON1T (XENONnT and LZ; DARWIN) experiments will be sensitive to a supernova burst up to 25 (35; 65) kpc from Earth at a significance of more than 5 sigma, observing approximately 35 (123; 704) events from a 27 Msun supernova progenitor at 10 kpc. Moreover, it will be possible to measure the average neutrino energy of all flavours, to constrain the total explosion energy, and to reconstruct the supernova neutrino light curve. Our results suggest that a large xenon detector such as DARWIN will be competitive with dedicated neutrino telescopes, while providing complementary information that is not otherwise accessible.Comment: 19 pages, 9 figures. Minor revisions compared to original version. Matches version published in Phys. Rev.

Treprostinil for pulmonary hypertension

Treprostinil is a stable, long-acting prostacyclin analogue which can be administered as a continuous subcutaneous infusion using a portable miniature delivery system. Subcutaneous treprostinil has been shown in a large multicenter randomized controlled trial to improve exercise capacity, clinical state, functional class, pulmonary hemodynamics, and quality of life in patients with pulmonary arterial hypertension, an uncommon disease of poor prognosis. Side effects include facial flush, headache, jaw pain, abdominal cramping, and diarrhea, all typical of prostacyclin, and manageable by symptom-directed dose adjustments, and infusion site pain which may make further treatment impossible in 7%–10% of the patients. Long-term survival in pulmonary arterial hypertension patients treated with subcutaneous treprostinil is similar to that reported with intravenous epoprostenol. There are uncontrolled data suggesting efficacy of subcutaneous treprostinil in chronic thromboembolic pulmonary hypertension. Treprostinil can also be administered intravenously, although increased doses, up to 2–3 times those given subcutaneously, appear to be needed to obtain the same efficacy. Preliminary results of a randomized controlled trial of inhaled treprostinil on top of bosentan and sildenafil therapies have shown significance on the primary endpoint, which was exercise capacity as assessed by the distance walked in 6 minutes. Trials of oral formulations of treprostinil have been initiated

Choriocarcinoma mimicking chronic thromboembolic pulmonary hypertension

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Antibiotic resistance surveillance of Klebsiella pneumoniae complex is affected by refined MALDI-TOF identification, Swiss data, 2017 to 2022.

BackgroundModern laboratory methods such as next generation sequencing and MALDI-TOF allow identification of novel bacterial species. This can affect surveillance of infections and antimicrobial resistance. From 2017, increasing numbers of medical microbiology laboratories in Switzerland differentiated Klebsiella variicola from Klebsiella pneumoniae complex using updated MALDI-TOF databases, whereas many laboratories still report them as K. pneumoniae or K. pneumoniae complex.AimOur study explored whether separate reporting of K. variicola and the Klebsiella pneumoniae complex affected the ANRESIS surveillance database.MethodsWe analysed antibiotic susceptibility rates and specimen types of K. variicola and non-K. variicola-K. pneumoniae complex isolates reported by Swiss medical laboratories to the ANRESIS database (Swiss Centre for Antibiotic Resistance) from January 2017 to June 2022.ResultsAnalysis of Swiss antimicrobial resistance data revealed increased susceptibility rates of K. variicola compared with species of the K. pneumoniae complex other than K. variicola in all six antibiotic classes tested. This can lead to underestimated resistance rates of K. pneumoniae complex in laboratories that do not specifically identify K. variicola. Furthermore, K. variicola strains were significantly more often reported from blood and primarily sterile specimens than isolates of the K. pneumoniae complex other than K. variicola, indicating increased invasiveness of K. variicola.ConclusionOur data suggest that refined differentiation of the K. pneumoniae complex can improve our understanding of its taxonomy, susceptibility, epidemiology and clinical significance, thus providing more precise information to clinicians and epidemiologists

Characteristics and survival data from Latvian pulmonary hypertension registry : comparison of prospective pulmonary hypertension registries in Europe

Publisher Copyright: © The Author(s) 2018.Patient registries are a valuable tool in the research of rare conditions such as pulmonary hypertension (PH). We report comprehensive hemodynamic and survival data of 174 patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), included in the prospective Latvian PH registry over a period of > 9 years. In total, 130 adult PAH patients (75%) and 44 adult CTEPH patients (25%) were enrolled. The median follow-up period was 33 months for PAH and 18 months for CTEPH, P = 0.001. Latvian CTEPH patients had significantly higher plasma levels of B-type natriuretic peptide, higher pulmonary vascular resistance, and lower cardiac index than Latvian PAH patients. Calculated incidence of PAH and CTEPH in Latvia in 2016 was 13.7 and 5.1 cases per million inhabitants, calculated prevalence was 45.7 and 15.7 cases per million inhabitants, respectively. Survival rates at one, three, and five years for PAH patients was 88.0%, 73.3%, and 58.1%, and 83.8%, 59.0%, and 44.2% for CTEPH patients, respectively. We compared our study results with data from European adult PH registries. Latvian PAH patients had the fourth lowest and CTEPH patients the lowest one-year survival rate among European adult PH registries. As most PH registries in Europe are small, yet with equivalent patient inclusion criteria, it would be desirable to combine these registries to produce more reliable and high-quality study results.publishersversionPeer reviewe

Calcium channel blockers reduce the antiplatelet effect of clopidogrel

ObjectivesBecause of the known CYP3A4 inhibition by calcium-channel blockers (CCBs), we hypothesized that there might be a drug-drug interaction between clopidogrel and dihydropyridines in patients with coronary artery disease.BackgroundClopidogrel is activated by CYP3A4, which also metabolizes CCBs of the dihydropyridine class.MethodsResponsiveness to clopidogrel was assessed by the vasodilator-stimulated phosphoprotein (VASP) phosphorylation assay and aggregometry in 200 patients with coronary artery disease undergoing percutaneous coronary intervention.ResultsThe platelet reactivity index (PRI) (in the VASP assay, normal range 69% to 100%) was higher in patients receiving both clopidogrel and CCBs (61%) as compared with patients receiving clopidogrel without CCBs (48%). The absolute difference was 13% (95% confidence interval: 6% to 20%; p = 0.001), and the relative difference approached 21%. A decreased platelet inhibition by clopidogrel (PRI >69%) was seen in 40% of patients with concomitant CCB treatment and in 20% of patients without concomitant treatment (chi-square test, p = 0.008). Intake of CCB remained an independent predictor of reduced platelet inhibition by clopidogrel after adjustment for cardiovascular risk factors. Adenosine diphosphate-induced platelet aggregation was 30% higher in patients on concomitant CCB treatment compared with patients without CCBs (p = 0.046). Moreover, intake of CCBs was associated with adverse clinical outcome. In vitro incubation with CCBs (nimodipine, verapamil, amlodipine, and diltiazem) did not alter the PRI or the adenosine diphosphate–induced platelet aggregation of patients taking clopidogrel. This finding indicates that the negative effect occurs in vivo, conceivably at the level of the CYP3A4 cytochrome.ConclusionsCoadministration of CCBs is associated with decreased platelet inhibition by clopidogrel