Graphene nanoribbons grown in hBN stacks for high-performance electronics.

Van der Waals encapsulation of two-dimensional materials in hexagonal boron nitride (hBN) stacks is a promising way to create ultrahigh-performance electronic devices1-4. However, contemporary approaches for achieving van der Waals encapsulation, which involve artificial layer stacking using mechanical transfer techniques, are difficult to control, prone to contamination and unscalable. Here we report the transfer-free direct growth of high-quality graphene nanoribbons (GNRs) in hBN stacks. The as-grown embedded GNRs exhibit highly desirable features being ultralong (up to 0.25 mm), ultranarrow (<5 nm) and homochiral with zigzag edges. Our atomistic simulations show that the mechanism underlying the embedded growth involves ultralow GNR friction when sliding between AA'-stacked hBN layers. Using the grown structures, we demonstrate the transfer-free fabrication of embedded GNR field-effect devices that exhibit excellent performance at room temperature with mobilities of up to 4,600 cm2 V-1 s-1 and on-off ratios of up to 106. This paves the way for the bottom-up fabrication of high-performance electronic devices based on embedded layered materials.

Tip Growth of Quasi-Metallic Bilayer Graphene Nanoribbons with Armchair Chirality.

Graphene nanoribbons (GNRs), quasi one-dimensional (1D) narrow strips of graphene, have shown promise for high-performance nanoelectronics due to their exceptionally high carrier mobility and structurally tunable bandgaps. However, producing chirality-uniform GNRs on insulating substrates remains a big challenge. Here, we report the successful growth of bilayer GNRs with predominantly armchair chirality and ultranarrow widths (<5 nm) on insulating hexagonal boron nitride (h-BN) substrates using chemical vapor deposition (CVD). The growth of GNRs is catalyzed by transition metal nanoparticles, including Fe, Co, and Ni, through a unique tip-growth mechanism. Notably, GNRs catalyzed by Ni exhibit a high purity (97.3%) of armchair chirality. Electron transport measurements indicate that the ultrathin bilayer armchair GNRs exhibit quasi-metallic behavior. This quasi-metallicity is further supported by density functional theory (DFT) calculations, which reveal a significantly reduced bandgap in bilayer armchair GNRs. The chirality-specific GNRs reported here offer promising advancements for the application of graphene in nanoelectronics.

Insulin resistance assessed by estimated glucose disposal rate and risk of incident cardiovascular diseases among individuals without diabetes: findings from a nationwide, population based, prospective cohort study.

BACKGROUND: Recent studies have suggested that insulin resistance (IR) contributes to the development of cardiovascular diseases (CVD), and the estimated glucose disposal rate (eGDR) is considered to be a reliable surrogate marker of IR. However, most existing evidence stems from studies involving diabetic patients, potentially overstating the effects of eGDR on CVD. Therefore, the primary objective of this study is to examine the relationship of eGDR with incidence of CVD in non-diabetic participants. METHOD: The current analysis included individuals from the China Health and Retirement Longitudinal Study (CHARLS) who were free of CVD and diabetes mellitus but had complete data on eGDR at baseline. The formula for calculating eGDR was as follows: eGDR (mg/kg/min) = 21.158 - (0.09 × WC) - (3.407 × hypertension) - (0.551 × HbA1c) [WC (cm), hypertension (yes = 1/no = 0), and HbA1c (%)]. The individuals were categorized into four subgroups according to the quartiles (Q) of eGDR. Crude incidence rate and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed to investigate the association between eGDR and incident CVD, with the lowest quartile of eGDR (indicating the highest grade of insulin resistance) serving as the reference. Additionally, the multivariate adjusted restricted cubic spine (RCS) was employed to examine the dose-response relationship. RESULTS: We included 5512 participants in this study, with a mean age of 58.2 ± 8.8 years, and 54.1% were female. Over a median follow-up duration of 79.4 months, 1213 incident CVD cases, including 927 heart disease and 391 stroke, were recorded. The RCS curves demonstrated a significant and linear relationship between eGDR and all outcomes (all P for non-linearity > 0.05). After multivariate adjustment, the lower eGDR levels were founded to be significantly associated with a higher risk of CVD. Compared with participants with Q1 of eGDR, the HRs (95% CIs) for those with Q2 - 4 were 0.88 (0.76 - 1.02), 0.69 (0.58 - 0.82), and 0.66 (0.56 - 0.79). When assessed as a continuous variable, per 1.0-SD increase in eGDR was associated a 17% (HR: 0.83, 95% CI: 0.78 - 0.89) lower risk of CVD, with the subgroup analyses indicating that smoking status modified the association (P for interaction = 0.012). Moreover, the mediation analysis revealed that obesity partly mediated the association. Additionally, incorporating eGDR into the basic model considerably improve the predictive ability for CVD. CONCLUSION: A lower level of eGDR was found to be associated with increased risk of incident CVD among non-diabetic participants. This suggests that eGDR may serve as a promising and preferable predictor and intervention target for CVD.

Sex difference in nocturnal blood pressure dipping in adolescents with varying degrees of adiposity.

BACKGROUND: For adolescents, abnormal dipping patterns in blood pressure (BP) are associated with early-onset organ damage and a higher risk of cardiovascular disorders in adulthood. Obesity is one of the most common reasons for abnormal BP dipping in young people. However, it is unknown whether the severity of obesity is associated with BP dipping status and whether this association is sex-dependent. METHODS: 499 participants between 12 and 17 years old with overweight or obesity underwent ambulatory blood pressure monitoring (ABPM) between April 2018 and January 2019 in Beijing and Baoding. Participants were grouped by body mass index (BMI) into overweight (BMI 85th-95th percentile), obese (BMI ≥ 95th percentile) and severely obese (BMI ≥ 120% of 95th percentile or ≥ 35 kg/m2) groups. Non-dipping was defined as a < 10% reduction in BP from day to night. The interaction effect between sex and obesity degree was also analyzed. RESULTS: 326 boys and 173 girls were included, of whom 130 were overweight, 189 were obese, and 180 were severely obese. Girls with severe obesity had a higher prevalence of non-dipping, but boys showed no significant differences in BP dipping status between obesity categories. In addition, as obesity severity went up, a more evident increase in night-time SBP was observed in girls than in boys. CONCLUSIONS: Severely obese is associated with a higher prevalence of non-BP dipping patterns in girls than in boys, which suggests that the relationship between the severity of obesity and BP dipping status might be sex-specific.

Association between Chinese visceral adiposity index and risk of stroke incidence in middle-aged and elderly Chinese population: evidence from a large national cohort study.

BACKGROUND: Abdominal obesity has long been considered as a crucial risk factor of stroke. Chinese visceral adiposity index (CVAI), a novel surrogate indicator of abdominal obesity, has been confirmed as a better predictor for coronary heart disease than other indicators in Asian population. However, the data on the relationship of CVAI with stroke is limited. The objective of our study is evaluating the relationship between CVAI and stroke incidence. METHODS: In the present study, we enrolled 7242 middle-aged and elderly residents from the China Health and Retirement Longitudinal Study (CHARLS) and placed them into groups according to quartile of CVAI. The outcome of interest was stroke. Kaplan-Meier curves were used to estimate the cumulative incidences of stroke. Cox regression analyses and multivariable-adjusted restricted cubic spline (RCS) curves were performed to evaluate the relationship between CVAI and incident stroke. Multiple sensitivity analyses and subgroups analyses were performed to test the robustness of the findings. RESULTS: During a median 84 months of follow-up, 612 (8.45%) participants experienced incident stroke, and the incidences of stroke for participants in quartiles (Q) 1-4 of CVAI were 4.42%, 7.29%, 9.06% and 13.04%, respectively. In the fully adjusted model, per 1.0-SD increment in CVAI has a significant increased risk of incident stroke: hazard ratio (HR) [95% confidence interval (CI)] was 1.17 (1.07-1.28); compared with participants in Q1 of CVAI, the HRs (95% CI) of incident stroke among those in Q2-4 were 1.47 (1.10-1.95), 1.62 (1.22-2.15), and 1.70 (1.28-2.27), respectively. Subgroups analyses suggested the positive association was significant in male participants, without diabetes, hypertension and heart disease. The findings were robust in all the sensitivity analyses. Additional, RCS curves showed a significant dose-response relationship of CVAI with risk of incident stroke (P for non-linear trend = 0.319). CONCLUSION: Increased CVAI is significantly associated with higher risk of stroke incidence, especially in male individuals, without hypertension, diabetes and heart disease. The findings suggest that baseline CVAI is a reliable and effective biomarker for risk stratification of stroke, which has far-reaching significance for primary prevention of stroke and public health.

Association between non-insulin-based insulin resistance indices and cardiovascular events in patients undergoing percutaneous coronary intervention: a retrospective study.

BACKGROUND: Insulin resistance (IR) has been confirmed that getting involved in the pathophysiological process of cardiovascular diseases (CVD). Recently, increasing evidence suggests metabolic score for insulin resistance (METS-IR), triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride and glucose (TyG) index, triglyceride glucose-body mass (TyG-BMI) index are simple and reliable surrogates for IR. However, their abilities in predicting cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) are not well explored. Therefore, this study aimed to investigate the association and evaluate the predictive performance of each index. METHODS: A total of 2533 consecutive participants undergoing PCI were included in this study, and the data from 1461 patients were used to determine the correlation of these non-insulin-based IR indices with major adverse cardiac and cerebrovascular events (MACCEs) via performing the multivariate logistic models and restricted cubic splines (RCS). RESULTS: During a median of 29.8 months follow-up, 195 cases of 1461 patients experienced incident MACCEs. In the overall population, both univariate and multivariate logistic regression analyses indicated no statistically significant connection between these IR indices and MACCEs. Subgroup analyses revealed significant interactions between age subgroups and TyG-BMI index, as well as METS-IR, and between sex subgroups and TyG index. In elderly patients, per 1.0-SD increment in TyG-BMI index and METS-IR had a significant association with MACCEs, with odds ratios (ORs) [95% confidence interval (CI)] of 1.24 (1.02-1.50) and 1.27 (1.04-1.56), respectively (both P < 0.05). Moreover, in female patients, all the IR indices showed significant associations with MACCEs. Multivariable-adjusted RCS curves demonstrated a linear relationship between METS-IR and MACCEs in elderly and female patients, respectively. However, all the IR indices failed to enhance the predictive performance of the basic risk model for MACCEs. CONCLUSION: All the four IR indices showed a significant association with MACCEs in female individuals, whereas only TyG-BMI index and METS-IR showed associations in elderly patients. Although the inclusion of these IR indices did not improve the predictive power of basic risk model in either female or elderly patients, METS-IR appears to be the most promising index for secondary prevention of MACCEs and risk stratification in patients undergoing PCI.

A novel AGK splicing mutation in a patient with Sengers syndrome and left ventricular non-compaction cardiomyopathy.

BACKGROUND: Sengers syndrome characterized by hypertrophic cardiomyopathy is an extremely rare genetic disorder. Sengers syndrome associated with left ventricular non-compaction (LVNC) has not been described. METHODS: Genetic testing was used to identify candidate AGK variants in the proband. The predicted molecular structures were constructed by protein modeling. Exon skipping caused by the identified splicing mutations was verified by in silico analyses and in vitro assays. The genotypic and phenotypic features of patients with AGK splicing mutations were extracted by a systematic review. RESULTS: The proband was characterized by Sengers syndrome and LVNC and caused by a novel compound heterozygous AGK splicing mutation. This compound mutation simultaneously perturbed the protein sequences and spatial conformation of the acylglycerol kinase protein. In silico and in vitro analyses demonstrated skipping of exons 7 and 8 and premature truncation as a result of exon 8 skipping. The systematic review indicated that patients with an AGK splicing mutation may have milder phenotypes of Sengers syndrome. CONCLUSIONS: The genotypic and phenotypic spectrums of Sengers syndrome have been expanded, which will provide essential information for genetic counseling. The molecular mechanism in AGK mutations can offer insights into the potential targets for treatment. IMPACT: First description of a child with Sengers syndrome and left ventricular non-compaction cardiomyopathy. A novel pathogenic compound heterozygous splicing mutation in AGK for Sengers syndrome was identified. The identified mutations led to exons skipping by in silico analyses and in vitro assays.

Childhood-Onset Refractory Hypertension Results from Neurofibromatosis Type 1 Caused by a Splicing NF1 Mutation.

INTRODUCTION: Neurofibromatosis type 1 (NF-1) is caused by mutations in the NF1 gene that encodes neurofibromin, a negative regulator of RAS proto-oncogene. Approximately one-third of the reported pathogenic mutations in NF1 are splicing mutations, but most consequences are unclear. The objective of this study was to identify the pathogenicity of splicing mutation in a Chinese family with NF-1 and determine the effects of the pre-mRNA splicing mutation by in vitro functional analysis. METHODS: Next-generation sequencing was used to screen candidate mutations. We performed a minigene splicing assay to determine the effect of the splicing mutation on NF1 expression, and three-dimensional structure models of neurofibromin were generated using SWISS-MODEL and PROCHECK methods, respectively. RESULTS: A pathogenic splicing mutation c.479+1G>C in NF1 was found in the proband characterized by childhood-onset refractory hypertension. In vitro analysis demonstrated that c.479+1G>C mutation caused the skipping of exon 4, leading to a glutamine-to-valine substitution at position 97 in neurofibromin and an open reading frame shift terminating at codon 108. Protein modeling showed that several major domains were missing in the truncated neurofibromin protein. CONCLUSION: The splicing mutation c.479+1G>C identified in a Chinese patient with NF-1 and childhood-onset refractory hypertension caused the skipping of exon 4 and a truncated protein. Our findings offer new evidence for the molecular diagnosis of NF-1.

Lipoprotein(a) is a new prognostic factor in patients with psoriasis and coronary artery disease: a retrospective cohort study.

BACKGROUND: The prognostic value of lipoprotein (Lp) (a) in patients who have suffered from coronary artery disease (CAD) has not been fully studied, and the results are inconsistent. This study was conducted to evaluate whether increased Lp(a) concentrations cause differences in clinical adverse outcomes in patients with psoriasis who have already suffered from CAD. METHODS: This retrospective cohort study included consecutive patients with psoriasis and CAD between January 2017 and May 2022 in our hospital. The clinical records were collected, and comparisons were made between patients in the low Lp(a) and high Lp(a) groups. Cox proportional hazard analysis and log-rank tests were used to evaluate the association between variables. RESULTS: Among 295 patients, 148 patients were in the low Lp(a) group, and 147 were in the high Lp(a) group. These two groups did not differ significantly in age, gender or body mass index. Compared with the low Lp(a) group, the levels of platelet counts (P = 0.038) and high sensitivity C reactive protein (P = 0.012) were higher in the high Lp(a) group. Patients in the high Lp(a) group had higher total cholesterol levels (P = 0.029) and lower triglyceride levels (P = 0.037). Among the whole cohort, clinical adverse events were not correlated with Lp(a) concentrations after a median follow-up of 3 years. However, in the subgroup analysis, there were significant differences in all-cause death (log rank P = 0.036) and rehospitalization (log rank P = 0.037) between the two groups in patients with diabetes; a difference in rehospitalization (log rank P = 0.042) was also found between the two groups in men. CONCLUSIONS: In patients with psoriasis and CAD, high levels of Lp(a) were related to a poor prognosis, especially in patients with diabetes and in men. These results will provide valuable information for the risk stratification of patients with psoriasis and CAD.

Apparent mineralocorticoid excess: comprehensive overview of molecular genetics.

Apparent mineralocorticoid excess is an autosomal recessive form of monogenic disease characterized by juvenile resistant low-renin hypertension, marked hypokalemic alkalosis, low aldosterone levels, and high ratios of cortisol to cortisone metabolites. It is caused by defects in the HSD11B2 gene, encoding the enzyme 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2), which is primarily involved in the peripheral conversion of cortisol to cortisone. To date, over 50 deleterious HSD11B2 mutations have been identified worldwide. Multiple molecular mechanisms function in the lowering of 11ß-HSD2 activity, including damaging protein stability, lowered affinity for the substrate and cofactor, and disrupting the dimer interface. Genetic polymorphism, environmental factors as well as epigenetic modifications may also offer an implicit explanation for the molecular pathogenesis of AME. A precise diagnosis depends on genetic testing, which allows for early and specific management to avoid the morbidity and mortality from target organ damage. In this review, we provide insights into the molecular genetics of classic and non-classic apparent mineralocorticoid excess and aim to offer a comprehensive overview of this monogenic disease.

Rapid cycling of reactive nitrogen in the marine boundary layer.

Nitrogen oxides are essential for the formation of secondary atmospheric aerosols and of atmospheric oxidants such as ozone and the hydroxyl radical, which controls the self-cleansing capacity of the atmosphere. Nitric acid, a major oxidation product of nitrogen oxides, has traditionally been considered to be a permanent sink of nitrogen oxides. However, model studies predict higher ratios of nitric acid to nitrogen oxides in the troposphere than are observed. A 'renoxification' process that recycles nitric acid into nitrogen oxides has been proposed to reconcile observations with model studies, but the mechanisms responsible for this process remain uncertain. Here we present data from an aircraft measurement campaign over the North Atlantic Ocean and find evidence for rapid recycling of nitric acid to nitrous acid and nitrogen oxides in the clean marine boundary layer via particulate nitrate photolysis. Laboratory experiments further demonstrate the photolysis of particulate nitrate collected on filters at a rate more than two orders of magnitude greater than that of gaseous nitric acid, with nitrous acid as the main product. Box model calculations based on the Master Chemical Mechanism suggest that particulate nitrate photolysis mainly sustains the observed levels of nitrous acid and nitrogen oxides at midday under typical marine boundary layer conditions. Given that oceans account for more than 70 per cent of Earth's surface, we propose that particulate nitrate photolysis could be a substantial tropospheric nitrogen oxide source. Recycling of nitrogen oxides in remote oceanic regions with minimal direct nitrogen oxide emissions could increase the formation of tropospheric oxidants and secondary atmospheric aerosols on a global scale.

Clinical characteristics of concurrent primary aldosteronism and renal artery stenosis: A retrospective case-control study.

Background: Rare cases of concurrent primary aldosteronism (PA) and renal artery stenosis (RAS) have been reported. Methods: In this retrospective case-control study, we selected a cohort of 10 PA with RAS patients and a control group of 20 PA without RAS patients from January 1, 2006, to January 1, 2016.  Results: All patients presented with refractory hypertension, and a nonstatistically significant trend toward lower mean serum potassium was seen in the PA with RAS group (p =.07). PA with RAS patients had lower mean orthostatic aldosterone-to-renin ratios (38.4 ± 41.4 ng dL-1/ng mL-1 h-1 vs. 87.4.4 ± 38.4 ng dL-1/ng mL-1 h-1, respectively; p < .01) and a higher false-negative rate (50% vs. 15%, respectively; p < .05) compared with controls. All misdiagnosed patients had the diagnosis of PA confirmed when we revaluated the repeated screening and confirmative tests because of residual hypertension or hypokalemia after successful revascularization of renal artery stenosis.  Conclusions: PA is easily missed in patients with RAS because of the high false-negative rate for screening tests. RAS patients with residual hypertension after successful renal angioplasty should be monitored for coexisting PA. Reevaluation of screening and confirmatory tests is helpful in establishing the correct diagnoses.

Is primary aldosteronism a potential risk factor for aortic dissection? A case report and literature review.

BACKGROUND: Primary aldosteronism (PA) increases the risk of cardiovascular morbidity, including stroke, coronary artery disease, atrial fibrillation, and heart failure. The relationship between primary aldosteronism and aortic dissection has rarely been reported. We report a case of aortic dissection caused by secondary hypertension from PA and review similar cases in the literature. CASE PRESENTATION: A 56-year-old woman with a history of surgery for aortic dissection presented for follow-up of hypertension and a left adrenal mass. She had been diagnosed with hypertension and hypokalemia in 2003. Blood pressure had been controlled by antihypertensive medications. In 2009, she presented with chest and back pain; she was diagnosed with aortic dissection by computed tomography (CT). She underwent placement of an endovascular aortic stent graft. CT at that time showed a left adrenal mass with a diameter of 1 cm. In 2017, CT reexamination revealed that the left adrenal mass had grown to 3 cm in diameter. Laboratory data showed blood potassium 2.4 mmol/L (reference range: 3.5-5.3 mmol/L). The plasma aldosterone/renin ratio was elevated because of suppressed plasma renin and elevated serum aldosterone levels. Plasma aldosterone levels were not suppressed after taking captopril. Positron emission tomography/CT showed that the left adrenal tumor radiographic uptake was slightly increased (maximum standardized uptake value of 2.2), and metastasis was not detected. Laparoscopic adrenalectomy was performed, and an adrenocortical adenoma was confirmed histopathologically. After surgery, blood pressure and laboratory findings were within their reference ranges without any pharmacological treatment. CONCLUSIONS: Our patient and the literature suggest that PA is a potential cause of aortic dissection. Diagnosing PA in the early stages of the disease and early treatment are important because affected patients may be at increased risk of aortic dissection.

Premature Stroke Secondary to Severe Hypertension Results from Liddle Syndrome Caused by a Novel SCNN1B Mutation.

INTRODUCTION: Liddle syndrome (LS), an autosomal dominant and inherited monogenic hypertension syndrome caused by pathogenic mutations in the epithelial sodium channel (ENaC) genes SCNN1A, SCNN1B, and SCNN1G. OBJECTIVE: This study was designed to identify a novel SCNN1B missense mutation in a Chinese family with a history of stroke, and to confirm that the identified mutation is responsible for LS in this family. METHODS: DNA samples were collected from the proband and 11 additional relatives. Next-generation sequencing was performed in the proband to find candidate variants. In order to exclude genetic polymorphism, the candidate variantin SCNN1B was verified in other family members, 100 hypertensives, and 100 healthy controls by Sanger sequencing. RESULTS: Genetic testing revealeda novel and rare heterozygous variant in SCNN1B in the proband. This variant resulted in a substitution of threonine instead of proline at codon 617, altering the PY motif of ß-ENaC. The identified mutation was only verified in 5 relatives. In silico analyses indicated that this variant was highly pathogenic. In this family, phenotypic heterogeneity was present among 6 LS patients. Tailored medicine with amiloride was effective in controlling hypertension and improving the serum potassium concentration in patients with LS. CONCLUSIONS: We identified a novel SCNN1B mutation (c.1849C>A) in a family affected by LS. Patients with LS, especially those with severe hypertension, should be alert for the occurrence of premature stroke. Timely diagnosis using genetic testing and tailored treatment with amiloride can help LS patients to avoid severe complications.

Truncated Epithelial Sodium Channel ß Subunit Responsible for Liddle Syndrome in a Chinese Family.

BACKGROUND/AIMS: Liddle syndrome (LS) is a rare autosomal dominant disease caused by mutations in genes coding for epithelial sodium channel (ENaC) subunits. The aim of this study was to identify the mutation responsible for the LS in an extended Chinese family. METHODS: DNA samples from the proband with early-onset, treatment-resistant hypertension, and hypokalemia and 19 additional relatives were all sequenced for mutations in exon 13 of the ß-ENaC and γ-ENaC genes, using amplification by polymerase chain reaction and direct DNA sequencing. RESULTS: Genetic testing of exon 13 of SCNN1B revealed duplication of guanine into a string of 3 guanines located at codon 602. This frameshift mutation is predicted to generate a premature stop codon at position 607, resulting in truncated ß-ENaC lacking the remaining 34 amino acids, including the crucial PY motif. Among a total of 9 participants with the identical mutation, different phenotypes were identified. Tailored treatment with amiloride was safe and effective in alleviating disease symptoms in LS. No mutation of SCNN1G was identified in any of the examined participants. CONCLUSIONS: We report here a family affected by LS harboring a frameshift mutation (c.1806dupG) with a premature stop codon deleting the PY motif of ß-ENaC. Our study demonstrates that the earlier LS patients are diagnosed by genetic testing and treated with tailored medication, the greater the likelihood of preventing or minimizing complications in the vasculature and target organs.

Automatic Identification of Tool Wear Based on Convolutional Neural Network in Face Milling Process.

Monitoring of tool wear in machining process has found its importance to predict tool life, reduce equipment downtime, and tool costs. Traditional visual methods require expert experience and human resources to obtain accurate tool wear information. With the development of charge-coupled device (CCD) image sensor and the deep learning algorithms, it has become possible to use the convolutional neural network (CNN) model to automatically identify the wear types of high-temperature alloy tools in the face milling process. In this paper, the CNN model is developed based on our image dataset. The convolutional automatic encoder (CAE) is used to pre-train the network model, and the model parameters are fine-tuned by back propagation (BP) algorithm combined with stochastic gradient descent (SGD) algorithm. The established ToolWearnet network model has the function of identifying the tool wear types. The experimental results show that the average recognition precision rate of the model can reach 96.20%. At the same time, the automatic detection algorithm of tool wear value is improved by combining the identified tool wear types. In order to verify the feasibility of the method, an experimental system is built on the machine tool. By matching the frame rate of the industrial camera and the machine tool spindle speed, the wear image information of all the inserts can be obtained in the machining gap. The automatic detection method of tool wear value is compared with the result of manual detection by high precision digital optical microscope, the mean absolute percentage error is 4.76%, which effectively verifies the effectiveness and practicality of the method.

Genetic screening of SCNN1B and SCNN1G genes in early-onset hypertensive patients helps to identify Liddle syndrome.

BACKGROUND: Liddle syndrome is an autosomal dominant form of monogenic hypertension. Phenotypic variability makes it difficult to identify patients with Liddle syndrome, resulting in misdiagnosis and severe complications at early age. OBJECTIVES: To identify mutation in SCNN1B and SCNN1G genes in an adolescent with suspicious Liddle syndrome and his family members and to explore the screening target subjects of Liddle syndrome. METHODS: Genetic analysis of the C-terminus of SCNN1B and SCNN1G genes was conducted in an adolescent, with treatment-resistant hypertension and hypokalemia, who was suspected of having Liddle syndrome, and his family members. A Medline research of the reported cases with Liddle syndrome was also performed. RESULTS: A recurrent SCNN1B mutation, c.1853C>A (p.P618H), was detected in the 19-year-old male patient, and family screening identified five additional members who were heterozygous for the mutation. The diagnosis of Liddle syndrome was made in all affected individuals. Despite the phenotypic variability, a systematic review of 54 reported index cases revealed the early-onset hypertension, aged no more than 30 years, as a common feature. CONCLUSIONS: Genetic screening for Liddle syndrome should be considered in hypertensive subjects with early penetrance, maybe no more than 30 years, after exclusion of common secondary causes of hypertension.

Left Ventricular Non-Compaction: A Cardiomyopathy With Acceptable Prognosis in Children.

BACKGROUND: Data on children with left ventricular non-compaction (LVNC) is sparse. The purpose of this study was to evaluate its clinical profiles in a population of Chinese children. METHODS: From January 2010 to March 2016, consecutive Chinese children (aged <18 years) with LVNC diagnosed by cardiovascular magnetic resonance (CMR) were prospectively recruited at Fuwai Hospital. RESULTS: A total of 41 Chinese children (male: 28%; mean age: 14±4years) were included in this study. Left ventricular non-compaction was not detected in 13 (32%) patients at initial echocardiographic evaluation. Congenital heart disease (CHD) was found in 11 (27%) patients. Four (10%) patients had Wolff-Parkinson-White (WPW) syndrome. Mean left ventricular ejection fraction (LVEF) was 41±15%. Late gadolinium enhancement (LGE) was detected in eight (20%) subjects. During a mean follow-up of 2.9 years, four (9%) patients died or received heart transplantation. These patients had lower systolic blood pressure (91±10 vs. 108±14mmHg; p=0.02), diastolic blood pressure (57±7 vs. 68±8mmHg; p=0.007) and LVEF (19±7 vs. 44±12%; p=0.002) than the survivors. In addition, advanced heart failure (100% vs. 16%; p=0.002) and LGE (50% vs. 5%; p=0.04) were detected more in these subjects. CONCLUSIONS: Left ventricular non-compaction is easily overlooked at echocardiographic assessment. Congenital heart disease and WPW syndrome were relatively common in LVNC children. The prognosis of children with LVNC seemed to be better than previous studies reported, and its long-term prognosis needs to be further investigated.

Photolysis of Particulate Nitrate as a Source of HONO and NOx.

Photolysis of nitric acid on the surface has been found recently to be greatly enhanced from that in the gas phase. Yet, photolysis of particulate nitrate (pNO3) associated with atmospheric aerosols is still relatively unknown. Here, aerosol filter samples were collected both near the ground surface and throughout the troposphere on board the NSF/NACR C-130 aircraft. The photolysis rate constants of pNO3 were determined from these samples by directly monitoring the production rates of nitrous acid (HONO) and nitrogen dioxide (NO2) under UV light (>290 nm) irradiation. Scaled to the tropical noontime condition on the ground level (solar zenith angle = 0°), the normalized photolysis rate constants (jpNO3N) are in the range from 6.2 × 10-6 s-1 to 5.0 × 10-4 s-1 with a median of 8.3 × 10-5 s-1 and a mean (±1 SD) of (1.3 ± 1.2) × 10-4 s-1. Chemical compositions, specifically nitrate loading and organic matter, affect the rate of photolysis. Extrapolated to ambient pNO3 loading conditions, e.g. ≤ 10 nmol m-3, the mean jpNO3N value is over 1.8 × 10-4 s-1 in the suburban, rural, and remote environments. Photolysis of particulate nitrate is thus a source of HONO and NO2 in the troposphere.

Transcatheter closure or surgical repair of right pulmonary artery-left atrial fistula.

Right pulmonary artery-left atrial fistula is a rare congenitalcardiac anomaly, and only a few articles published so far have reported the diagnosis and treatment of right pulmonary artery-left atrial fistula. In this study, we report three cases of successful transcatheter closure or surgical repair of right pulmonary artery-left atrial fistula.