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71.
In this report, we describe a national-scale monitoring of the SARS-CoV-2 (SC-2) variant dynamics in Israel, using multiple-time sampling of 13 wastewater treatment plants. We used a combination of inclusive and selective quantitative PCR assays that specifically identify variants A19/A20 or B.1.1.7 and tested each sample for the presence and relative viral RNA load of each variant. We show that between December 2020 and March 2021, a complete shift in the SC-2 variant circulation was observed, where the B.1.1.7 replaced the A19 in all examined test points. We further show that the normalized viral load (NVL) values and the average new cases per week reached a peak in January 2021 and then decreased gradually in almost all test points, in parallel with the progression of the national vaccination campaign, during February–March 2021. This study demonstrates the importance of monitoring SC-2 variant by using a combination of inclusive and selective PCR tests on a national scale through wastewater sampling, which is far more amendable for high-throughput monitoring compared with sequencing. This approach may be useful for real-time dynamics surveillance of current and future variants, such as the Omicron (BA.1, BA.2) and other variants.  相似文献   
72.
A porous TiO2 layer was prepared with the plasma electrolytic oxidation (PEO) of Ti. In a further step, Pd was deposited on the TiO2 surface layer using the adsorption method. The activity of the Pd/TiO2/Ti catalyst was investigated during the oxidation of CO to CO2 in a mixture of air with 5% CO. The structure of the catalytic active layer was studied using a scanning electron microscope equipped with an energy dispersive spectrometer (SEM-EDS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), inductively coupled plasma mass spectrometry (ICP-MS), and X-ray diffraction (XRD). The PEO process provided a porous TiO2 layer with a uniform thickness in the range of 5–10 µm, which is desirable for the production of Pd-supported catalysts. A TOF-SIMS analysis showed the formation of Pd nanoparticles after the adsorption treatment. The conversion of CO to CO2 in all samples was achieved at 150–280 °C, depending on the concentration of Pd. The composition of Pd/ TiO2/Ti was determined using ICP-MS. The optimum concentration of Pd on the surface of the catalyst was approximately 0.14% wt. This concentration was obtained when a 0.4% PdCl2 solution was used in the adsorption process. Increasing the concentration of PdCl2 did not lead to a further improvement in the activity of Pd/ TiO2/Ti.  相似文献   
73.
In the present work, we provide a comprehensive numerical investigation of the magnetic properties and phase spectra of three types of spin-1/2 branched chains consisting of one, two and three side spins per unit block with intra-chain interaction and a uniform inter-chain interaction in the presence of an external magnetic field. In a specific magnetic field interval, the low-temperature magnetization of these chains shows a step-like behavior with a pronounced plateau depending on the strength and the type of intra-chain interaction being ferromagnetic or antiferromagnetic. We demonstrate that when inter-chain interaction J1 is antiferromagnetic and intra-chain interaction J2 is ferromagnetic, the magnetization of the models manifests a smooth increase without a plateau, which is evidence of the existence of a Luttinger-like spin liquid phase before reaching its saturation value. On the other hand, when J1 is ferromagnetic and J2 is antiferromagnetic, the low-temperature magnetization of the chain with two branches shows an intermediate plateau at one-half of the saturation magnetization that breaks a quantum spin liquid phase into two regions. The magnetization of the chain with three branches exhibits two intermediate plateaus and two regions of a quantum spin liquid. We demonstrate that the chains with more than one side spin illustrate in their ground-state phase diagram a Kosterlitz–Thouless transition from a gapful phase to a gapless spin liquid phase.  相似文献   
74.
75.
The possibility of the formation of an alkali–silicate reaction (ASR) is a crucial issue for the service life of concrete. The coexistence of key parameters such as the presence of alkalis, reactive SiO2, humidity, and temperature predetermine the possibility of its formation and application. When an ASR gel forms, it results in the concreting cracking and spalling as well as in the deterioration of its overall properties. The risk of ASR depends on the concentration of alkalis and their mobility, which influence their ability to penetrate the concrete. The objective of this study was to determine the ionic mobility of not only Na+ and K+, but Ca2+ as well, from external sources (0.5 and 1.0 mol/L solutions of Na/K carbonate, nitrate, and hydroxide) to a cementitious matrix as the precursor for ASR. The concentrations of ions in both the immersion solutions (ICP) and the cementitious matrix itself (SEM-EDX) were studied as a function of time, from 0 to 120 days, for leaching, and according to temperature (25 and 40 °C). The reaction products were characterized using SEM-EDX. Different diffusion rates and behavior were observed depending on the anion type of the external alkali source. Both sodium and potassium ions in all the three environments studied, namely carbonate, hydroxide, and nitrate, penetrated into the composite and further into its structure by different mechanisms. The action of hydroxides, in particular, transformed the original hydration products into calcium-silicate-hydrate (CASH) or ASR gel, while nitrates crystallized in pores and did not cause any changes in the hydration product. The driving force was the increased temperature of the experiment as well as the increased concentration of the solution to which the test specimen was exposed.  相似文献   
76.
BackgroundAdvanced heart failure (HF) patients usually poorly tolerate guideline‐directed HF medical therapy (GDMT) and suffer high rates of morbidity and mortality. The use of continuous inotropes in the outpatient settings is hampered by previous data showing excess morbidity. We aimed to assess the safety and efficacy of repetitive, intermittent, short‐term intravenous milrinone therapy in advanced HF patients with an intention to introduce and up‐titrate GDMT and improve functional class.HypothesisRepetitive, intermittent milrinone therapy may assist with the stabilization of advanced HF patients.MethodsAdvanced HF patients treated with beta‐blockers and implanted with defibrillators were initiated with repetitive, intermittent short‐term intravenous milrinone therapy at our HF outpatient unit. Patients were prospectively followed with defibrillator interrogation, functional class assessment, B‐natriuretic peptide (BNP) levels, and echocardiography parameters.ResultsThe cohort included 24 patients with a mean 330 ± 240 days of milrinone therapy exposure. Mean age was 73 ± 6 years with male predominance (96%). Following milrinone therapy, median BNP levels decreased significantly (882 [286−3768] to 631 [278−1378] pg/ml, p = .017) with a significant reduction in the number of patients with New York Heart Association (NYHA) Class III and IV (p = .012, 0.013) and an increase in number of patients on GDMT. Importantly, the number of total sustained ventricular tachycardia events and HF hospitalizations did not change.ConclusionsIn this small cohort of advanced HF, repetitive, intermittent, short‐term milrinone therapy was found to be safe and potentially efficacious.  相似文献   
77.
PurposeClinic-based psychosocial interventions, including volunteer-based ones, may be a cost-efficient and acceptable means of integrating psychosocial support into cancer care during radiotherapy. The present study evaluated a new psychosocial volunteer support program in a large radiotherapy clinic.Methods and MaterialsPatients were asked to complete a demographic and satisfaction with care questionnaire. Clinic volunteers were asked to report their interactions with patients on shift logs.ResultsOf the 182 participating patients, 93 (51%) recalled meeting a volunteer in the clinic, with the 2 most common support types provided being the following: “listening and caring,” and “information on services.” Analysis of 224 volunteers' shift logs indicated that almost all interactions (94%) were initiated by the volunteers, and almost half (47%) involved the patients' companions in the clinic. The most common support type documented was “information and navigation” (71%), followed by “emotional” (47%), “diversional” (21%), and “physical/practical” (17%) support.ConclusionsTrained volunteers can effectively provide clinic-based psychosocial support and information to a high proportion of radiotherapy patients. These findings demonstrate that volunteer support is a feasible means of meeting the psychosocial needs of patients with cancer attending outpatient radiotherapy clinics, who may not require or want professional psychosocial support.  相似文献   
78.
Colorectal cancer screening guidelines are identical for men and women despite reported differences in epidemiology, endoscopy performance, screening preferences, and screening uptake. High-quality research is needed to determine whether gender aspects may in real world increase acceptance and overcome screening barriers, which may lead to better use of limited resources allocated for public health.  相似文献   
79.
Background/Aim: Acute non‐specific abdominal pain (NSAP) is prevalent in 6–25% of the general population and is a common cause of admission to the emergency department (ED). Despite involvement of substantial financial and human resources, there are few data on long‐term outcome after initial diagnosis. The aim of this study was to evaluate long‐term outcome of patients initially admitted with NSAP to an ED. Methods: The study involves a 5‐year follow‐up analysis of prospectively collected data on 104 patients admitted to our ED in 2003 with NSAP. Primary end‐point was clinical outcome 5 years after initial ED admission. Predictive risk factors were assessed using a multivariate regression model. Results: 29 patients (28%) had recurring NSAP 5 years after initial ED admission, 76% of these patients received (multiple) diagnostic examinations and 13% eventually required diagnostic (or therapeutic) surgery. Although approximately half of patients with recurring NSAP eventually received a definite diagnosis, 30% still suffered from recurrent abdominal pain. Using regression analysis, no single factor in our dataset could be identified as a predictor for NSAP persistence. Conclusion: The long‐term impact for patients initially admitted to our ED with acute NSAP is significant – 28% of patients continue to suffer from recurring NSAP after 5 years. NSAP therefore remains, despite more advanced diagnostic tools, a true and, as yet, unsolved problem.  相似文献   
80.
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