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Organic electronics is emerging for large-area applications such as photovoltaic cells, rollable displays or electronic paper. Its future development and integration will require a simple, low-power organic memory, that can be written, erased and readout electrically. Here we demonstrate a non-volatile memory in which the ferroelectric polarisation state of an organic tunnel barrier encodes the stored information and sets the readout tunnel current. We use high-sensitivity piezoresponse force microscopy to show that films as thin as one or two layers of ferroelectric poly(vinylidene fluoride) remain switchable with low voltages. Submicron junctions based on these films display tunnel electroresistance reaching 1,000% at room temperature that is driven by ferroelectric switching and explained by electrostatic effects in a direct tunnelling regime. Our findings provide a path to develop low-cost, large-scale arrays of organic ferroelectric tunnel junctions on silicon or flexible substrates. Ferroelectric organic materials can be used for tunnel barriers in memory devices as a cheaper and eco-friendly replacement of their inorganic counterparts. Here, Tian et al . use poly(vinylidene fluoride) with 1–2 layer thickness to achieve giant tunnel electroresistance of 1,000% at room temperature.

Background It is unclear whether the offspring of subclinical hypothyroidism (SCH) pregnant rats still have abnormal cardiac development, and whether early intervention with L-T4 can improve the abnormality of these offspring. Therefore, the aim of this study was to investigate the effect of early L-T4 intervention on the heart development of offspring of SCH pregnant rats and its possible molecular mechanism. Methods Eighty female Wistar rats were randomly divided into Sham group (placebo control), SCH group, LT4-E10 group (L-T4 treatment started on the 10th day of gestation), and LT4-E13 group (L-T4 treatment started on the 13th day of gestation). Each group was further divided into E16 (16th day of gestation), E18 (18th day of gestation), P5 (5th day postnatal day), and P10 (10th day postnatal day) subgroups. The levels of serum TT4 and TSH, the ratio of heart weight to body weight of offspring rats, the expression of metabolic enzymes, and the histopathology of cardiomyocytes were determined. To elucidate the effects of L-T4 on cardiac development of offspring of SCH pregnant rats, the expression levels of GATA4, Nkx2–5 and proteins involved in BMP4/Smad4 signaling pathway were detected by immunohistochemistry, real time quantitative polymerase chain reaction and Western blotting to elucidate the molecular mechanism of L-T4 regulating the heart development of the offspring of SCH pregnant rats. Results Compared with Sham group, serum TSH was significantly increased in SCH pregnant rats. Moreover, early L-T4 intervention significantly reduced the levels of serum TSH. Compared with the offspring in the SCH group, early L-T4 intervention significantly increased the heart weight, heart weight to body weight ratio, the activities of succinate dehydrogenase (SDH), Na + /K + -ATPase and Ca 2+ -ATPase, but reduced myocardial cell shrinkage and nuclear staining, hyperemia/congestion and vacuolar degeneration. In addition, early L-T4 intervention not only significantly increased the mRNA and protein expression of Gata4 and Nkx2–5, but also increased the protein expression involved in BMP4/Smad4 signal pathway in myocardium of the offspring of SCH pregnant rats. Conclusions Early L-T4 intervention can regulate the cardiac development of the offspring of SCH pregnant rats by activating BMP4/Smad4 signaling pathway and increasing the expression of Gata4 and Nkx2–5 proteins.

γ-Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the central nervous system, has several well-known physiological functions and has been applied to the production of many drugs and functional foods. The technology of GABA production via submerged fermentation by Streptococcus salivarius subsp. thermophilus Y2 was investigated in this paper. It indicated that the GABA production was related to the biochemical characteristics of glutamate decarboxylase (GAD) of S. salivarius subsp. thermophilus Y2. After 24 h of fermentation at 37 °C, which is the suitable culture conditions for GAD-production, then the culture condition were adjusted to the optimal temperature (40 °C) and pH (4.5) for the GAD reaction activity in biotransformation of cells and pyridoxal 5′-phosphate (0.02 mmol/l) were added to the broth at the 48 h, the GABA production was increased up to 1.76-fold, reaching 7984.75 ± 293.33 mg/l. The strain shows great potential use as a starter for GABA-containing yoghurt, cheese and other functional fermented food productions.

Vibrio harveyi is a normal flora present in seawater, but in recent years, with large density aquaculture, V. harveyi has become one of the causative organisms in fish and shrimp. In this study, V. harveyi VieA gene was used as the target to design primers and establish the loop-mediated isothermal amplification ( LAMP) combined with visual lateral flow test strip (LFD). The optimal reaction conditions were optimized as 60°C, 45 min, 1.2 mM Mg 2+ , 0.64 mM dNTPs, 0.25 mM betaine, and 16:1 ratio of internal/external primers. The results showed that the established LAMP assay was able to specifically detect V. harveyi with a sensitivity of 3.4 × 10 –5 ng/µL. Clinical applicability analysis revealed that only V. harveyi was detected in the samples for pearl gentian grouper and whiteleg shrimp artificially infected by Vibrio . Therefore, we established a visual, reliable, rapid and sensitive LAMP-LFD method for detecting V. harveyi in aquatic animals.

Stable chest pain is a common indication for cardiac catheterization. We assessed the prognostic value of the Prospective Multicenter Imaging Study for Evaluation (PROMISE) Minimal-Risk Tool in identifying patients who are at very low risk of obstructive coronary artery disease (CAD) or downstream cardiovascular adverse outcomes. We applied the PROMISE Minimal-Risk Tool to consecutive patients without known CAD who underwent elective cardiac catheterization for stable angina from January 1, 2000 to December 31, 2014 in the Duke Databank for Cardiovascular Disease (DDCD). Patients with scores >0.46 (top decile of lowest-risk from the PROMISE cohort) were classified as low-risk. Logistic regression modeling compared likelihood of freedom from obstructive coronary artery disease on index angiography, 2-year survival, and 2-year survival free of myocardial infarction (MI) and MI/revascularization between low- and non low-risk patients. Alternative cut points to define low- risk patients were also explored. Among 6251 patients undergoing cardiac catheterization for stable chest pain, 1082 (17.3%) were low-risk per the PROMISE minimal-risk tool. Among low risk patients, obstructive coronary artery disease was observed in 14.9% and left main disease (≥ 50% Stenosis) was rare (0.9%). Compared with other patients, low risk patients had a higher likelihood of freedom from obstructive coronary disease on index catheterization (85.1% vs. 44.2%, OR 4.84, 95% CI 4.06-5.77). Low risk patients had significantly higher survival (98.2% vs. 94.4%, OR 3.18, 95% CI 1.99-5.08), MI-free survival (97.2% vs. 91.9%, OR 3.03, 95% CI 2.07-4.45), and MI/revascularization-free survival (86.2 vs. 59.9%, OR 4.19, 95% CI 3.48-5.05) at 2 years than non-low risk patients. Operating characteristics for predicting the outcomes of interest varied modestly depending on the low-risk cut-point used but the positive predictive value for 2 year freedom from death was >98% regardless. The PROMISE minimal-risk tool identifies 17% of stable chest pain patients referred to cardiac catheterization as low risk. These patients have a low prevalence of obstructive CAD and better survival than non-low risk patients. While this suggests that these patients are unlikely to benefit from catheterization, further research is needed to confirm a favorable downstream prognosis with medical management alone.

Possessing only essential genes, a minimal cell can reveal mechanisms and processes that are critical for the persistence and stability of life 1 , 2 . Here we report on how an engineered minimal cell 3 , 4 contends with the forces of evolution compared with the Mycoplasma mycoides non-minimal cell from which it was synthetically derived. Mutation rates were the highest among all reported bacteria, but were not affected by genome minimization. Genome streamlining was costly, leading to a decrease in fitness of greater than 50%, but this deficit was regained during 2,000 generations of evolution. Despite selection acting on distinct genetic targets, increases in the maximum growth rate of the synthetic cells were comparable. Moreover, when performance was assessed by relative fitness, the minimal cell evolved 39% faster than the non-minimal cell. The only apparent constraint involved the evolution of cell size. The size of the non-minimal cell increased by 80%, whereas the minimal cell remained the same. This pattern reflected epistatic effects of mutations in ftsZ , which encodes a tubulin-homologue protein that regulates cell division and morphology 5 , 6 . Our findings demonstrate that natural selection can rapidly increase the fitness of one of the simplest autonomously growing organisms. Understanding how species with small genomes overcome evolutionary challenges provides critical insights into the persistence of host-associated endosymbionts, the stability of streamlined chassis for biotechnology and the targeted refinement of synthetically engineered cells 2 , 7 – 9 . An engineered minimal cell evolves to escape the negative consequences of genome streamlining.

Abstract Purpose The objective of this study was to explore whether there were any differences between the theoretical recommendations for children's supracondylar humeral fractures (CSHF) according to the American Academy of Orthopaedic Surgeons (AAOS) guidelines and the treatments they actually received in our institution. Methods We retrospectively reviewed the medical charts and radiographs of all CSHFs at our hospital between January 2015 and December 2018. In all, 301 children meeting our inclusion criteria were identified and evaluated using the AAOS-Appropriate Use Criteria (AUC) application for supracondylar humerus fractures. Actual treatment was then compared with the treatment recommended by the AUC. Results Actual operative management was undertaken in 0/58 (0%) Gartland type I fractures, 61/108 (56.5%) type II fractures and 98/135 (72.6%) type III fractures. Actual nonoperative management was undertaken in 58/58 (100%) Gartland type I fractures, 47/108 (43.5%) type II fractures and 37/135 (27.4%) type III fractures. Surgeon decisions for nonoperative treatment were in agreement with the AUC recommendations 100% of the time, whereas surgeon decisions for surgery matched the AUC recommendations 65.4% of the time. Predictors of actual operative management were age (p =0.003), fracture classification (p =0.000), associated orthopaedic injury requiring surgery (p =0.025) and anterior humeral line (AHL) not intersecting the capitellum (p =0.008). Conclusion We found low agreement between actual treatments and the AUC-recommended ‘appropriate’ treatments. The AUC favoured operative intervention more frequently largely on the basis of fracture classification while we emphasized age, fracture classification, associated orthopaedic injury requiring surgery and alignment of the AHL with the capitellum in our operative decision-making process. Level of evidence Therapeutic Level II

A renewable granular iron-based technology for hydrogen sulfide removal from sediment and water in box culverts and storm drains is discussed. Iron granules, including granular ferric hydroxide (GFH), granular ferric oxide (GFO) and rusted waste iron crusts (RWIC) embedded in the sediment phase removed aqueous hydrogen sulfide formed from sedimentary biological sulfate reduction. The exhausted iron granules were exposed to dissolved oxygen and this regeneration process recovered the sulfide removal capacities of the granules. The recovery is likely attributable to the oxidation of the ferrous iron precipitates film and the formation of new reactive ferric iron surface sites on the iron granules and sand particles. GFH and RWIC showed larger sulfide removal capacities in the sediment phase than GFO, likely due to the less ordered crystal structures on their surfaces. This study demonstrates that the iron granules are able to remove hydrogen sulfide from sediment and water in box culverts and storm drains and they have the potential to be regenerated and reused by contacting with dissolved oxygen.

BackgroundEmerging evidence has revealed that obstructive sleep apnea (OSA) is associated with non-alcoholic fatty liver disease (NAFLD). However, the impact of OSA on NAFLD among obese patients undergoing metabolic and bariatric surgery (MBS), especially during follow-up period, remains unclear.ObjectiveTo analyze the correlation based on preoperative characteristics and postoperative conditions among bariatric patients with comorbid OSA and NAFLD. Methods: Clinical data of patients who underwent MBS in our institution between January 2016 and June 2019 were reviewed retrospectively. Correlation analysis and linear regressions were used to identify how OSA links with NAFLD before and after treatment of MBS.ResultsOf 308 patients, 181 were diagnosed with OSA and enrolled in the present study, and 127 completed follow-up visits at 6 months. The proportion of NAFLD in the mild-moderate OSA and severe OSA groups was 75.0% and 96.0%, respectively. MBS was effective at improving sleep apnea and nocturnal hypoxia, as well as liver steatosis and fibrosis (P < 0.05). And we also found that there were significant correlations not only between OSA- and NAFLD-related characteristics at baseline but also between their improvements after surgery, eventually leading to similar prognosis of NAFLD for both groups (P < 0.05), no matter what presurgical differences existed. In addition, the results of the univariate and multivariate linear regression analyses supported preoperative liver/spleen Hounsfield units ratio (LSR) by computerized tomography (CT) as an independent predictor of the effect of MBS on liver steatosis.ConclusionIn conclusion, MBS plays a pivotal role in the control of medical conditions in obese patients with OSA and NAFLD. Given the correlation between OSA and NAFLD in the present study, in the case of both the severity at baseline as well as the improvement after surgery, OSA may pose an impact on the prognosis of NAFLD in bariatric patients.

With the increasing white pollution problem and the enhancement of people’s awareness of environmental protection, the bio-based and biodegradable polymers have received unprecedented attention. Poly-lactic acid (PLA) is considered as one of the most potential alternatives to petroleum-based polymer materials. However, Due to its inherent brittleness and the difficulties of post-disposal and recycling caused by traditional processing methods, PLA has not been fully accepted by the market. To overcome the issues, self-reinforcing PLA composites (SRPLA) were prepared with different PLA grades as the matrix and the reinforcement respectively. High toughness SRPLA were prepared by hot pressing using PLA3052 casting films as the matrix and PLA6202 oriented tapes fabricated by solid state drawing as the reinforcement. In addition, the toughening mechanism was analyzed. Mechanical tests showed that the strength, modulus and elongation at break were increased by 124.3%, 114% and 145.2% respectively compared with pure PLA hot pressed film. Particularly, the tensile toughness of SRPLA is more than 200% that of pure PLA. The interface debonding and tape pullout were the main toughening mechanisms.