This work proposes a novel approach to developing a core component for a near-infrared (NIR) spectrometer with wavelength tunability, which is based on a liquid crystal (LC)-in-cavity structure as a ...hybrid photonic crystal (PC). By electrically altering the tilt angle of the LC molecules under applied voltage, the proposed PC/LC photonic structure consisting of an LC layer sandwiched between two multilayer films generates transmitted photons at specific wavelengths as defect modes within the photonic bandgap (PBG). The relationship between the number of defect-mode peaks and the cell thickness is investigated using a simulated approach based on the 4 × 4 Berreman numerical method. Furthermore, the defect-mode wavelength shifts driven by various applied voltages are studied experimentally. To minimize the power consumption of the optical module for spectrometric application, cells of different thicknesses are explored for the wavelength-tunability performance of the defect modes scanning through the entire free spectral ranges to the wavelengths of their next higher orders at null voltage. A 7.9 μm thick PC/LC cell is verified to attain the low operating voltage of merely 2.5 V
required to successfully cover the entire NIR spectral range between 1250 and 1650 nm. The proposed PBG structure is thus an excellent candidate for application in monochromator or spectrometer development.
Antiferromagnetic spintronics is an emerging field of non‐volatile data storage and information processing. The zero net magnetization and zero stray fields of antiferromagnetic materials eliminate ...interference between neighbor units, leading to high‐density memory integrations. However, this invisible magnetic character at the same time also poses a great challenge in controlling and detecting magnetic states in antiferromagnets. Here, two antiferromagnetic spin states close in energy in strained BiFeO3 thin films at room temperature are discovered. It can be reversibly switched between these two non‐volatile antiferromagnetic states by a moderate magnetic field and a non‐contact optical approach. Importantly, the conductivity of the areas with each antiferromagnetic textures is drastically different. It is conclusively demonstrated the capability of optical writing and electrical reading of these newly discovered bistable antiferromagnetic states in the BiFeO3 thin films.
Two bistable and reversibly controllable antiferromagnetic states in strained BFO film are discovered. These two non‐volatile antiferromagnetic states are successfully patterned with a non‐contact approach combining both optical and magnetic methods. The written antiferromagnetic pattern is electrically readable with at least 30% signal difference. This work promises an alternative route toward practical applications of antiferromagnetic spintronics.
Detecting clandestine, intermittent release of heavy metal pollution into natural and man-made water ways is challenging. Conventional chemical methods are both labor intensive and expensive. A ...recent approach combining ion-exchange resins with the capabilities of X-ray fluorescence core scanners (XRF-CS) therefore is of great interest. In short, ion-exchange resin is deployed in the water using small sachets, the resin is then collected, dried, filled into sample holders and scanned using XRF-CS. Ion-exchange resins take up heavy metals in proportion to the concentration in the ambient water, with a correlation coefficient (R
) between concentration and XRF-CS counts better than 0.96 for most elements. However, a number of parameters influence the measurements. Different drying methods introduce differences in the XRF counts because of lattice bound water, resin shrinkage, and disaggregation of the resin particles. Furthermore, the newly developed sample carrier, which was constructed using 3D printed polymers, contains trace amounts of elements that may influence the sample measurements through edge effects and secondary fluorescence. In the tested sample carrier materials, substantial levels of Cr, Fe, Co, and Zn were detected, while Ca, Ti, Ni, Cu, Ga showed variable levels. Ba, Tl and Bi show very low levels, and Pb is only of importance in the PLA carrier. It is therefore necessary to streamline the analysis-process to ensure that the variations in sample treatment and drying and filling methods are minimized. It is also recommended that only spectra from the center of the compartments are used for the evaluation to avoid edge effects caused by secondary fluorescence of metals in the compartment walls. Although the technique of using ion-exchange resin sachets and XRF-CS analysis is only semi-quantitative, it is a cost effective and fast way to monitor large areas for environmental pollution, and the new sample carrier greatly contributes to make the process faster and less error prone.
Background
Antihyperglycemic drugs have been linked to new‐onset atrial fibrillation (NAF). However, the effect of the different classes of antihyperglycemic drugs on the development of NAF in ...elderly patients has not been well studied. In this study, we investigated the association between different classes of antihyperglycemic drugs and NAF in elderly patients.
Materials and methods
This was a nested case–control study performed using the database of National Health Insurance programme in Taiwan. Each participant aged 65 years and older who were NAF from 2005 to 2012 were assigned to the NAF group, whereas case was sex‐, age‐, diabetes duration‐, index date‐matched, and Charlson Comorbidity Index score‐matched randomly selected participant without NAF were assigned to the non‐NAF group. Multivariable logistic regression model was used for the estimation of odds ratios (ORs) and 95% confidence intervals (CIs) of NAF associated with use of different classes of antihyperglycemic agents. Nonusers served as the reference group.
Results
We identified 1958 cases and 7832 controls. The risk of NAF after adjusting for sex, age, comorbidities and concurrent medication was higher among the users of insulin than among the nonusers (OR, 1·58; 95% CI, 1·37–1·82). Patients who took dipeptidyl peptidase 4 inhibitors were at lower risk of developing NAF than the nonusers (OR, 0·65; 95% CI, 0·45–0·93).
Conclusions
In this population, use of dipeptidyl peptidase 4 inhibitor was associated with a low risk of NAF. Insulin use was associated with a significant increase in the risk of NAF during the long‐term follow‐up.
Utilizing a cognitive perspective, this article examines the social processes through which teachers come to understand the Common Core State Standards. The authors begin by identifying three beliefs ...that have important implications for policy implementation: self-efficacy, resource adequacy, and value for clients. They measure those beliefs and the Common Core discussion networks that emerge among teachers at three points in time. Through the use of SIENA models, the authors explore how networks and beliefs coevolve within schools. Unlike prior research on social networks, which consistently finds strong homophilous tendencies, this research finds no evidence that teachers seek out coworkers who hold similar beliefs. Rather, teachers relied on preexisting formal and informal relationships to guide interactions. Those interactions were characterized by social influence, whereby a teacher's own beliefs adapted toward the beliefs held by the members of their social network. The findings offer a novel perspective on the complex dynamic that occurs within organizations as new policies are unveiled and employees interact with one another to understand the changes those policies entail.
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•Global methylation and oxidative DNA damage levels in nanomaterial handling workers were assessed.•8-isoprostane in exhaled breath condensate of workers exposed to nanoparticles was ...higher.•8-OHdG was negatively correlated with global methylation.•Exposure to metal oxide nanoparticles may lead to global methylation and DNA oxidative damage.
This is the first study to assess global methylation, oxidative DNA damage, and lipid peroxidation in workers with occupational exposure to metal oxide nanomaterials (NMs). Urinary and white blood cell (WBC) 8-hydroxydeoxyguanosine (8-OHdG), and exhaled breath condensate (EBC) 8-isoprostane were measured as oxidative stress biomarkers. WBC global methylation was measured as an epigenetic alteration. Exposure to TiO2, SiO2, and indium tin oxide (ITO) resulted in significantly higher oxidative biomarkers such as urinary 8-OHdG and EBC 8-isoprostane. However, significantly higher WBC 8-OHdG and lower global methylation were only observed in ITO handling workers. Significant positive correlations were noted between WBC and urinary 8-OHdG (Spearman correlation r=0.256, p=0.003). Furthermore, a significant negative correlation was found between WBC 8-OHdG and global methylation (r=−0.272, p=0.002). These results suggest that exposure to metal oxide NMs may lead to global methylation, DNA oxidative damage, and lipid peroxidation.
•Reaction of O2•– + HOCl provides a potent HO• and RCS source for advanced oxidation•Organic probe compounds are effectively degraded by in situ generated HO• and RCS•HO• and RCS exposures up to ...5×10-10 and 10-9 M×s are comparable to other AOPs•Treatment remains effective even at DOC levels typical of natural and reuse waters•Only minor impacts of treatment on formation of regulated DBPs are observed
The reaction of hypochlorous acid (HOCl) with superoxide radical (O2•–) – a source of hydroxyl radical (HO•) and various reactive chlorine species (RCS) – was investigated as the basis for a novel non-photochemical advanced oxidation process (AOP). Moderately stable (t1/2 ~ minutes) aqueous O2•– stocks were prepared by several approaches at pH>12 and either (a) added directly to aqueous free available chlorine (FAC; i.e., HOCl/OCl–) at circumneutral pH, or (b) premixed with alkaline FAC and then acidified to pH 7, to degrade various organic probe compounds via in situ generated HO• and RCS. Radical production was optimal at HO2•/O2•–0/FAC0 ~ 2, with ~0.8 mol HO• formed/mol FAC consumed, and HO• and RCS exposures reaching ~5×10−10 and ~10−9 M×s, respectively. Similar trends were observed in natural waters and organic matter-amended phosphate buffer containing up to 5 mgC/L of dissolved organic carbon. Direct formation of oxyhalides, trihalomethanes (THMs), and haloacetic acids (HAAs), was minimal, though THM and HAA formation was moderately enhanced during post-chlorination of O2•–/FAC-treated solutions. This process could provide a beneficial addition to the range of available AOPs due to its high radical exposures, simplicity, rapid time-scales, potential for on-site O2•– generation, and widespread accessibility of FAC and other reagents.
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Summary Background Whether concomitant therapy is superior to bismuth quadruple therapy or 14-day triple therapy for the first-line treatment of Helicobacter pylori infection remains poorly ...understood. We aimed to compare the efficacy and safety of 10-day concomitant therapy, 10-day bismuth quadruple therapy, and 14-day triple therapy in the first-line treatment of H pylori. Methods In this multicentre, open-label, randomised trial, we recruited adult patients (aged >20 years) with H pylori infection from nine medical centres in Taiwan. Patients who had at least two positive tests from the rapid urease test, histology, culture, or serology or who had a single positive13 C-urea breath test for gastric cancer screening were eligible for enrolment. Patients were randomly assigned (1:1:1) to either concomitant therapy (lansoprazole 30 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg, all given twice daily) for 10 days; bismuth quadruple therapy (bismuth tripotassium dicitrate 300 mg four times a day, lansoprazole 30 mg twice daily, tetracycline 500 mg four times a day, and metronidazole 500 mg three times a day) for 10 days; or triple therapy (lansoprazole 30 mg, amoxicillin 1 g, and clarithromycin 500 mg, all given twice daily) for 14 days. A computer-generated permuted block randomisation sequence with a block size of 6 was used for randomisation, and the sequence was concealed in an opaque envelope until the intervention was assigned. Investigators were masked to treatment allocation. The primary outcome was the eradication frequency of H pylori with first-line therapy assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov , number NCT01906879. Findings Between July 17, 2013, and April 20, 2016, 5454 patients were screened for eligibility. Of these, 1620 patients were randomly assigned in this study. The eradication frequencies were 90·4% (488/540 95% CI 87·6–92·6) for 10-day bismuth quadruple therapy, 85·9% (464/540 82·7–88·6) for 10-day concomitant therapy, and 83·7% (452/540 80·4–86·6) for 14-day triple therapy in the intention-to-treat analysis. 10-day bismuth quadruple therapy was superior to 14-day triple therapy (difference 6·7% 95% CI 2·7–10·7, p=0·001), but not 10-day concomitant therapy. 10-day concomitant therapy was not superior to 14-day triple therapy. The frequency of adverse events was 67% (358/533) in patients treated with 10-day bismuth quadruple therapy, 58% (309/535) in patients treated with 10-day concomitant therapy, and 47% (252/535) in patients treated with 14-day triple therapy. Interpretation Bismuth quadruple therapy is preferable to 14-day triple therapy in the first-line treatment in the face of rising prevalence of clarithromycin resistance. Concomitant therapy given for 10 days might not be optimum and a longer treatment length should be considered. Funding National Taiwan University Hospital and Ministry of Science and Technology of Taiwan.
The complex population of microbes in the human gastrointestinal (GI) tract interacts with itself and with the host, exerting a deep influence on health and disease development. The development of ...modern sequencing technology has enabled us to gain insight into GI microbes. Helicobacter pylori colonization significantly affects the gastric microenvironment, which in turn affects gastric microbiota and may be correlated with colonic microbiota changes. Crosstalk between H. pylori and GI commensal flora may play a role in H. pylori-related carcinogenicity and extragastric manifestations. We review current knowledge on how H. pylori shapes GI microbiota with a specific focus on its impact on the stomach and colon. We also review current evidence on colonic microbiota changes attributed to eradication therapy based on the clinical studies performed to date.
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