In the classic transistor, the number of electric charge carriers--and thus the electrical conductivity--is precisely controlled by external voltage, providing electrical switching capability. This ...simple but powerful feature is essential for information processing technology, and also provides a platform for fundamental physics research. As the number of charges essentially determines the electronic phase of a condensed-matter system, transistor operation enables reversible and isothermal changes in the system's state, as successfully demonstrated in electric-field-induced ferromagnetism and superconductivity. However, this effect of the electric field is limited to a channel thickness of nanometres or less, owing to the presence of Thomas-Fermi screening. Here we show that this conventional picture does not apply to a class of materials characterized by inherent collective interactions between electrons and the crystal lattice. We prepared metal-insulator-semiconductor field-effect transistors based on vanadium dioxide--a strongly correlated material with a thermally driven, first-order metal-insulator transition well above room temperature--and found that electrostatic charging at a surface drives all the previously localized charge carriers in the bulk material into motion, leading to the emergence of a three-dimensional metallic ground state. This non-local switching of the electronic state is achieved by applying a voltage of only about one volt. In a voltage-sweep measurement, the first-order nature of the metal-insulator transition provides a non-volatile memory effect, which is operable at room temperature. Our results demonstrate a conceptually new field-effect device, extending the concept of electric-field control to macroscopic phase control.
The nature of the pseudogap phase of the copper oxides ('cuprates') remains a puzzle. Although there are indications that this phase breaks various symmetries, there is no consensus on its ...fundamental nature
. Fermi-surface, transport and thermodynamic signatures of the pseudogap phase are reminiscent of a transition into a phase with antiferromagnetic order, but evidence for an associated long-range magnetic order is still lacking
. Here we report measurements of the thermal Hall conductivity (in the x-y plane, κ
) in the normal state of four different cuprates-La
Nd
Sr
CuO
, La
Eu
Sr
CuO
, La
Sr
CuO
and Bi
Sr
La
CuO
. We show that a large negative κ
signal is a property of the pseudogap phase, appearing at its critical hole doping, p*. It is also a property of the Mott insulator at p ≈ 0, where κ
has the largest reported magnitude of any insulator so far
. Because this negative κ
signal grows as the system becomes increasingly insulating electrically, it cannot be attributed to conventional mobile charge carriers. Nor is it due to magnons, because it exists in the absence of magnetic order. Our observation is reminiscent of the thermal Hall conductivity of insulators with spin-liquid states
, pointing to neutral excitations with spin chirality
in the pseudogap phase of cuprates.
Background
Improving patients' oral hygiene is an option for preventing postoperative pneumonia that may be caused by aspiration of oral and pharyngeal secretions. Whether preoperative oral care by a ...dentist can decrease postoperative complications remains controversial. A retrospective cohort study was undertaken to assess the association between preoperative oral care and postoperative complications among patients who underwent major cancer surgery.
Methods
The nationwide administrative claims database in Japan was analysed. Patients were identified who underwent resection of head and neck, oesophageal, gastric, colorectal, lung or liver cancer between May 2012 and December 2015. The primary outcomes were postoperative pneumonia and all‐cause mortality within 30 days of surgery. Patient background was adjusted for with inverse probability of treatment weighting using propensity scoring.
Results
Of 509 179 patients studied, 81 632 (16·0 per cent) received preoperative oral care from a dentist. A total of 15 724 patients (3·09 per cent) had postoperative pneumonia and 1734 (0·34 per cent) died within 30 days of surgery. After adjustment for potential confounding factors, preoperative oral care by a dentist was significantly associated with a decrease in postoperative pneumonia (3·28 versus 3·76 per cent; risk difference − 0·48 (95 per cent c.i. −0·64 to−0·32) per cent) and all‐cause mortality within 30 days of surgery (0·30 versus 0·42 per cent; risk difference − 0·12 (−0·17 to −0·07) per cent).
Conclusion
Preoperative oral care by a dentist significantly reduced postoperative complications in patients who underwent cancer surgery.
Preoperative dental care reduces postoperative pneumonia
Purpose
Pheochromocytoma crisis is a life-threatening endocrine emergency that requires prompt diagnosis and treatment. Because of its rarity, sudden onset, and lack of internationally uniform and ...validated diagnostic criteria, pheochromocytoma crisis remains to be fully clarified. Therefore, we aimed to describe the clinical characteristics and outcomes of pheochromocytoma crisis through a literature review.
Methods
We performed a systematic literature search of PubMed/MEDLINE database, Igaku-Chuo-Zasshi (Japanese database), and Google Scholar to identify case reports of pheochromocytoma crisis published until February 5, 2021. Information was extracted and analyzed from the literature that reported adequate individual patient data of pheochromocytoma crisis in English or Japanese. Cases were also termed as pheochromocytoma multisystem crisis (PMC) if patients had signs of hyperthermia, multiple organ failure, encephalopathy, and labile blood pressure.
Results
In the 200 cases of pheochromocytoma crisis identified from 187 articles, the mean patient age was 43.8 ± 15.5 years. The most common symptom was headache (39.5%). The heart was the most commonly damaged organ resulting from a complication of a pheochromocytoma crisis (99.0%), followed by the lungs (44.0%) and the kidney (21.5%). PMC accounted for 19.0% of all pheochromocytoma crisis cases. After excluding 12 cases with unknown survival statuses, the mortality rate was 13.8% (26/188 cases). Multivariable logistic regression analysis revealed that nausea and vomiting were significantly associated with a higher mortality rate.
Conclusion
Pheochromocytoma can present with different symptomatology, affecting different organ systems. Clinicians should be aware that patients with nausea or vomiting are at a higher risk of death because of pheochromocytoma crisis.
Signatures of sulfur isotope mass-independent fractionation (S-MIF) have been observed in stratospheric sulfate aerosols deposited in polar ice. The S-MIF signatures are thought to be associated with ...stratospheric photochemistry following stratospheric volcanic eruptions, but the exact mechanism responsible for the production and preservation of these signatures is debated. In order to identify the origin and the mechanism of preservation for these signatures, a series of laboratory photochemical experiments were carried out to investigate the effect of temperature and added O2 on the S-MIF produced by two absorption band systems of SO2: photolysis in the 190 to 220 nm region and photoexcitation in the 250 to 350 nm region. The SO2 photolysis (SO2 + h nu arrow right SO + O) experiments showed S-MIF signals with large 34S/34S fractionations, which increases with decreasing temperature. The overall S-MIF pattern observed for photolysis experiments, including high 34S/34S fractionations, positive mass-independent anomalies in 33S, and negative anomalies in 36S, is consistent with a major contribution from optical isotopologue screening effects and data for stratospheric sulfate aerosols. In contrast, SO2 photoexcitation produced products with positive S-MIF anomalies in both 33S and 36S, which is different from stratospheric sulfate aerosols. SO2 photolysis in the presence of O2 produced SO3 with S-MIF signals, suggesting the transfer of the S-MIF anomalies from SO to SO3 by the SO + O2 + M arrow right SO3 + M reaction. This is supported with energy calculations of stationary points on the SO3 potential energy surfaces, which indicate that this reaction occurs slowly on a single adiabatic surface, but that it can occur more rapidly through intersystem crossing. Based on our experimental results, we estimate a termolecular rate constant on the order of 10-37 cm6 molecule-2 s-1. This rate can explain the preservation of mass independent isotope signatures in stratospheric sulfate aerosols and provides a minor, but important, oxidation pathway for stratospheric SO2. The production and preservation of S-MIF signals requires a high SO2 column density to allow for optical isotopologue screening effects to occur and to generate a large enough signature that it can be preserved. In addition, the SO2 plume must reach an altitude of around 20 to 25 km, where SO2 photolysis becomes a dominant process. These experiments are the first step towards understanding the origin of the sulfur isotope anomalies in stratospheric sulfate aerosols.
The use of implementation strategies is an active and purposive approach to translate research findings into routine clinical care. The Expert Recommendations for Implementing Change (ERIC) ...identified and defined discrete implementation strategies, and Proctor and colleagues have made recommendations for specifying operationalization of each strategy. We use empirical data to test how the ERIC taxonomy applies to a large dissemination and implementation initiative aimed at taking cardiac prevention to scale in primary care practice.
EvidenceNOW is an Agency for Healthcare Research and Quality initiative that funded seven cooperatives across seven regions in the USA. Cooperatives implemented multi-component interventions to improve heart health and build quality improvement capacity, and used a range of implementation strategies to foster practice change. We used ERIC to identify cooperatives' implementation strategies and specified the actor, action, target, dose, temporality, justification, and expected outcome for each. We mapped and compiled a matrix of the specified ERIC strategies across the cooperatives, and used consensus to resolve mapping differences. We then grouped implementation strategies by outcomes and justifications, which led to insights regarding the use of and linkages between ERIC strategies in real-world scale-up efforts.
Thirty-three ERIC strategies were used by cooperatives. We identified a range of revisions to the ERIC taxonomy to improve the practical application of these strategies. These proposed changes include revisions to four strategy names and 12 definitions. We suggest adding three new strategies because they encapsulate distinct actions that were not described in the existing ERIC taxonomy. In addition, we organized ERIC implementation strategies into four functional groupings based on the way we observed them being applied in practice. These groupings show how ERIC strategies are, out of necessity, interconnected, to achieve the work involved in rapidly taking evidence to scale.
Findings of our work suggest revisions to the ERIC implementation strategies to reflect their utilization in real-work dissemination and implementation efforts. The functional groupings of the ERIC implementation strategies that emerged from on-the-ground implementers will help guide others in choosing among and linking multiple implementation strategies when planning small- and large-scale implementation efforts.
Registered as Observational Study at www.clinicaltrials.gov ( NCT02560428 ).
Polyelectrolyte film fabrication by successive spraying of polycation and polyanion solutions is described and compared to classic dipping. The poly(styrenesulfonate)/poly(allylamine) system is ...examined in detail. The influence of various parameters such as spraying time, polyelectrolyte concentration, and effect of film drying during multilayer construction is investigated. It is found that film deposition by spraying is easily controlled and very reliable. The thickness of the multilayers grows linearly with the number of deposition cycles similarly to what is observed when dipping substrates or when polyelectrolyte solutions flow over a surface. The assembly of films is very fast and leads to films with small surface roughness as estimated by atomic force microscopy and X-ray reflectometry. Spray deposition allows achieving regular multilayer growth even under conditions for which dipping fails to produce homogeneous films (e.g., extremely short contact times). Moreover, because drainage constantly removes a certain quantity of the excess material arriving at the surface, one can even skip the rinsing step and, thus, speed up even further the whole buildup process.
The objective of this crossover experiment was to investigate the effect of a methane inhibitor, 3-nitrooxypropanol (3NOP), on enteric methane emission, methane isotopic composition, and rumen ...fermentation and microbial profile in lactating dairy cows. The experiment involved 6 ruminally cannulated late-lactation Holstein cows assigned to 2 treatments: control and 3NOP (60 mg/kg of feed dry matter). Compared with the control, 3NOP decreased methane emission by 31% and increased hydrogen emission from undetectable to 1.33 g/d. Methane emissions per kilogram of dry matter intake and milk yield were also decreased 34% by 3NOP. Milk production and composition were not affected by 3NOP, except milk fat concentration was increased compared with the control. Concentrations of total VFA and propionate in ruminal fluid were not affected by treatment, but acetate concentration tended to be lower and acetate-to-propionate ratio was lower for 3NOP compared with the control. The 3NOP decreased the molar proportion of acetate and increase those of propionate, butyrate, valerate, and isovalerate. Deuterium-to-hydrogen ratios of methane and the abundance of 13CH3D were similar between treatments. Compared with the control, minor (4‰) depletion in the 13C/12C ratio was observed for 3NOP. Genus composition of methanogenic archaea (Methanobrevibacter, Methanosphaera, and Methanomicrobium) was not affected by 3NOP, but the proportion of methanogens in the total cell counts tended to be decreased by 3NOP. Prevotella spp., the predominant bacterial genus in ruminal contents in this experiment, was also not affected by 3NOP. Compared with the control, Ruminococcus and Clostridium spp. were decreased and Butyrivibrio spp. was increased by 3NOP. This experiment demonstrated that a substantial inhibition of enteric methane emission by 3NOP in dairy cows was accompanied with increased hydrogen emission and decreased acetate-to-propionate ratio; however, neither an effect on rumen archaeal community composition nor a significant change in the isotope composition of methane was observed.
Although endoscopic submucosal dissection (ESD) is becoming accepted as an established treatment for superficial esophageal squamous cell neoplasms, the risks for developing postoperative stricture ...have not been elucidated.
This was a retrospective study at a single institution. From January 2002 to October 2008, 65 patients with high-grade intraepithelial neoplasms (HGINs) or m2 carcinomas treated by ESD were enrolled. Predictors of postoperative stricture were investigated by comparing results from 11 patients who developed strictures with those from 54 patients who did not.
Significant differences between the two groups were observed in longitudinal diameter (45.0 +/- 15.9 mm vs. 31.5 +/- 13.6 mm) and circumferential diameter (37.2 +/- 8.6 mm vs. 26.8 +/- 9.7 mm) of the resected specimens, and the proportion of extension to the whole circumference of the lumen (< 1 / 2/ > 1 / 2/ > 3 / 4 : 2 / 4 / 5 vs. 40 / 13 / 1), histologic depth (HGIN/m2 : 2 / 9 vs. 41 / 13), and procedure time (85.6 +/- 42.8 minutes vs. 53.3 +/- 30.1 minutes). Multivariate analysis revealed that circumferential extension of > 3 / 4 (odds ration OR: 44.2; 95 % confidence interval CI: 4.4 - 443.6) and histologic depth to m2 (OR: 14.2; 95 %CI: 2.7 - 74.2) are reliable risk factors. Subanalysis for each category by combinations of these risk factors revealed that patients with lesions in > 3 / 4 of the circumferential area were associated with a high rate of postoperative stricture. By contrast, patients with HGIN lesions in < 3 / 4 extension have no probability of postoperative strictures. Additionally, subanalysis of patients with m2 lesions in < 3 / 4 circumferential extension revealed that circumferential diameter can be a reliable predictor for postoperative stricture.
Circumferential extension and histologic depth are the reliable risk factors for postoperative strictures. In combination with circumferential diameter, we can perform effective and appropriate preventive balloon dilatations after esophageal ESD.
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