Predicting the risk of 1-year mortality among patients hospitalized for acute heart failure in China

BACKGROUND

We aimed to develop and validate a model to predict 1-year mortality risk among patients hospitalized for acute heart failure (AHF), build a risk score and interpret its application in clinical decision making.

METHODS

By using data from China Patient-Centred Evaluative Assessment of Cardiac Events Prospective Heart Failure Study, which prospectively enrolled patients hospitalized for AHF in 52 hospitals across 20 provinces, we used multivariate Cox proportional hazard model to develop and validate a model to predict 1-year mortality.

RESULTS

There were 4,875 patients included in the study, 857 (17.58%) of them died within 1-year following discharge of index hospitalization. A total of 13 predictors were selected to establish the prediction model, including age, medical history of chronic obstructive pulmonary disease and hypertension, systolic blood pressure, Kansas City Cardiomyopathy Questionnaire-12 score, angiotensin converting enzyme inhibitor or angiotensin receptor blocker at discharge, discharge symptom, N-terminal pro-brain natriuretic peptide, high-sensitivity troponin T, serum creatine, albumin, blood urea nitrogen, and highly sensitive C-reactive protein. The model showed a high performance on discrimination (C-index was 0.759 [95% confidence interval: 0.739, 0.778] in development cohort and 0.761 [95% confidence interval: 0.731, 0.791] in validation cohort), accuracy, calibration, and outperformed than several existed risk scores. A point-based risk score was built to stratify low- (0-12), intermediate- (13-16), and high-risk group (≥17) among patients.

CONCLUSIONS

A prediction model using readily available predictors was developed and internal validated to predict 1-year mortality risk among patients hospitalized for AHF. It may serve as a useful tool for individual risk stratification and informing decision making to improve clinical care.

Associations of cumulative depressive symptoms within 1-year of discharge with subsequent mortality among patients hospitalized for acute heart failure: Findings from The China PEACE Prospective Heart Failure Study

BACKGROUND

To examine the associations between cumulative depressive symptoms and subsequent mortality among patients hospitalized for acute hear failure (AHF).

METHODS

By using data from a prospective cohort study of patients with HF, depressive symptoms were measured by using Patient Health Questionnaire-2 (PHQ-2) at admission, 1-and 12-month after discharge. Cumulative depressive symptoms were interpreted by cumulative PHQ-2 score and cumulative times of depressive symptoms. Outcomes included subsequent 3-year all-cause and cardiovascular mortality.

RESULTS

We included 2347 patients with the median follow-up of 4.4 (interquartile range [IQR]: 4.0-5.0) years. Tertile 3 of cumulative PHQ-2 score had the highest risk of all-cause (hazard ratio [HR]: 1.47, 95 % confidence interval [CI]: 1.21-1.78) and cardiovascular mortality (HR: 1.51, 95 % CI: 1.21-1.89) compared with Tertile 1; patients with≥2 times of depressive symptoms had the highest risk of all-cause (HR: 1.62, 95 % CI: 1.31-2.00) and cardiovascular mortality (HR: 1.60, 95 % CI: 1.25-2.05) compared with patients without any depressive symptom. Cumulative PHQ-2 score provided the highest level of incremental prognostic ability in predicting the risk of all-cause (C-statistics: 0.64, 95 % CI: 0.62-0.66) and cardiovascular mortality (C-statistics: 0.65, 95 % CI: 0.62-0.67) on the basis of Get With The Guidelines-Heart Failure score.

CONCLUSION

Cumulative depressive symptoms were associated with the increased risk of subsequent mortality and provided incremental prognostic ability for the outcomes among patients with HF. Repeated depressive symptom measurements could be helpful to monitor long-term depressive symptoms, identify targeted patients and perform psychological interventions and social support to improve clinical outcomes among patients with AHF.

Association of cumulative health status with subsequent mortality in patients with acute heart failure

OBJECTIVE

We aim to examine the association between long-term cumulative health status and subsequent mortality among patients with acute heart failure (HF).

METHODS

Based on a national prospective cohort study of patients hospitalized for HF, we measured health status by Kansas City Cardiomyopathy Questionnaire (KCCQ)-12 at 4 time points, i.e. admission, 1-,6- and 12-month after discharge. Cumulative health status was interpreted by cumulative KCCQ-12 score and cumulative times of good health status. Outcomes included subsequent all-cause and cardiovascular mortality. Multivariable Cox proportional hazard models were performed to examine the association between cumulative health status and subsequent mortality.

RESULTS

Totally, 2328 patients (36.7% women and median age 66 [IQR: 56-75] years) were included, the median follow-up was 4.34 (IQR: 3.93-4.96) years. Compared with Quartile 4, the lowest Quartile 1 had the highest HR for all-cause mortality (2.96; 95% CI: 2.26-3.87), followed by Quartile 2 (1.79; 95% CI: 1.37-2.34) and Quartile 3 (1.62; 95% CI: 1.23-2.12). Patients with 0-time of good health status had the highest risk of all-cause mortality (HR: 2.41, 95% CI: 1.69-3.46) compared with patients with 4-times of good health status. Similar associations persisted for cardiovascular mortality.

CONCLUSIONS

A greater burden of cumulative health status indicated worse survival among patients hospitalized for HF. Repeated KCCQ measurements could be helpful to monitor long-term health status and identify patients vulnerable to death. Clinical Trial Registration: www.clinicaltrials.gov (NCT02878811).

Effects of cumulative cognitive function within 1-year of discharge on subsequent mortality among patients hospitalized for acute heart failure: A nationwide prospective cohort study

BACKGROUNDS

To examine the association between cumulative cognitive function and subsequent mortality among patients hospitalized for acute heart failure (AHF).

METHODS

Based on a prospective cohort of patients hospitalized for AHF, cognitive function was measured by using Mini-Cog test at admission, 1- and 12-month following discharge. Cumulative cognitive function was interpreted by cumulative Mini-Cog score and cumulative times of cognitive impairment. Outcomes included subsequent all-cause and cardiovascular mortality.

RESULTS

1454 patients hospitalized for AHF with median follow-up of 4.76 (interquartile range [IQR]: 4.18-5.07) years were included. Tertile 1 of cumulative Mini-Cog score had the highest risk of all-cause (hazard ratio [HR]: 1.52, 95% confidence interval [CI]: 1.14-2.03) and cardiovascular mortality (HR: 1.40, 95% CI: 1.02-1.93) compared with Tertile 3; patients with ≥ 2 times of cognitive impairment had the highest risk of all-cause (HR: 1.34, 95% CI: 1.03-1.73) and cardiovascular mortality (HR: 1.25, 95% CI: 0.93-1.67) compared with patients without any cognitive impairment. Cumulative Mini-Cog score provided the highest incremental prognostic ability in predicting all-cause (C-statistics: 0.64, 95% CI: 0.61-0.66) and cardiovascular mortality (C-statistics: 0.63, 95% CI: 0.60-0.67) risk on the basis of Get With The Guidelines-Heart Failure score.

CONCLUSION

Poor cumulative cognitive function was associated with increased risk of subsequent mortality and provided incremental prognostic ability for the outcomes among patients with AHF. Longitudinal assessment and monitoring of cognitive function among patients with AHF would be of great importance in identifying patients at greater risk of self-care absence for optimizing personal disease management in clinical practice.

Long-Term Cumulative High-Sensitivity C-Reactive Protein and Mortality Among Patients With Acute Heart Failure

Background Elevated hsCRP (high-sensitivity C-reactive protein) level is associated with worse prognosis among patients hospitalized for heart failure. However, the prognostic value of the long-term cumulative hsCRP remains unknown. Methods and Results We consecutively enrolled patients hospitalized for heart failure and collected their hsCRP data at admission and 1 and 12 months after discharge. Long-term cumulative hsCRP was evaluated using 2 approaches, cumulative hsCRP level quartiles and cumulative times of high hsCRP levels. Patients were classified into 4 groups by cumulative hsCRP level quartiles and cumulative times of high hsCRP levels (0- to 3-times: number of times that hsCRP levels were higher than cutoff values at admission or 1 or 12 months), respectively. Multivariable Cox models were used to assess the association of mortality with cumulative hsCRP. A total of 1281 patients were included; the median age was 64 (interquartile range, 54-73) years, and 35.4% were women. Over a 4.8-year (interquartile range, 4.2-5.1) follow-up, 374 (29.2%) patients died. Elevated long-term cumulative hsCRP level was related to higher mortality. Specifically, taking the quartile 1 as the reference, the hazard ratios (HRs) were 1.29 (95% CI, 0.92-1.81) for quartile 2, 1.62 (95% CI, 1.16-2.25) for quartile 3, and 2.38 (95% CI, 1.75-3.23) for quartile 4. Similarly, compared with the patients with 0-times (hsCRP level lower than the cutoff values in all 3 time points) of high hsCRP level, the HRs were 1.36 for 1-time (hsCRP level higher than the cutoff value in one of the 3 time points) (95% CI, 0.92-2.01), 1.95 for 2-times (hsCRP levels higher than the cutoff values in 2 of the 3 time points) (95% CI, 1.34-2.82), and 2.80 for 3-times (hsCRP levels higher than the cutoff values in the 3 time points) (95% CI, 1.97-4.00). Conclusions Increasing long-term cumulative hsCRP level was associated with worse outcomes in patients hospitalized for acute heart failure. Repeated hsCRP measurements could assist physicians in identifying patients with a high risk of death. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02878811.

Individual Trajectories of Health Status During the First Year of Discharge From Hospitalization for Heart Failure and Their Associations With Death in the Following Years

Background Improving health status is one of the major goals in the management of heart failure (HF). However, little is known about the long-term individual trajectories of health status in patients with acute HF after discharge. Methods and Results We enrolled 2328 patients hospitalized for HF from 51 hospitals prospectively and measured their health status via the Kansas City Cardiomyopathy Questionnaire-12 at admission and 1, 6, and 12 months after discharge, respectively. The median age of the patients included was 66 years, and 63.3% were men. Six patterns of Kansas City Cardiomyopathy Questionnaire-12 trajectories were identified by a latent class trajectory model: persistently good (34.0%), rapidly improving (35.5%), slowly improving (10.4%), moderately regressing (7.4%), severely regressing (7.5%), and persistently poor (5.3%). Advanced age, decompensated chronic HF, HF with mildly reduced ejection fraction, HF with preserved ejection fraction, depression symptoms, cognitive impairment, and each additional HF rehospitalization within 1 year of discharge were associated with unfavorable health status (moderately regressing, severely regressing, and persistently poor) (P<0.05). Compared with the pattern of persistently good, slowly improving (hazard ratio [HR], 1.50 [95% CI, 1.06-2.12]), moderately regressing (HR, 1.92 [1.43-2.58]), severely regressing (HR, 2.26 [1.54-3.31]), and persistently poor (HR, 2.34 [1.55-3.53]) were associated with increased risks of all-cause death. Conclusions One-fifth of 1-year survivors after hospitalization for HF experienced unfavorable health status trajectories and had a substantially increased risk of death during the following years. Our findings help inform the understanding of disease progression from a patient perception perspective and its relationship with long-term survival. Registration URL: https://www.clinicaltrials.gov; unique identifier: NCT02878811.

Age-Related Trends in the Predictive Value of Carotid Intima-Media Thickness for Cardiovascular Death: A Prospective Population-Based Cohort Study

Background The age-related trends in the predictive ability of carotid intima-media thickness (CIMT) for cardiovascular risk remain unclear. We aimed to identify the age-related trends in the predictive value of CIMT for cardiovascular death. Methods and Results In a prospective cohort of adults aged 35 to 75 years without history of cardiovascular disease who were enrolled between 2014 and 2020, we measured CIMT at baseline and collected the vital status and cause of death. We divided the study population into 4 age groups (35-44, 45-54, 55-64, and 65-75 years). Competing risk models were fitted to estimate the associations between CIMT and cardiovascular death. The added values of CIMT in prediction were assessed by the differences of the Harrell's concordance index and the net reclassification improvement index. We included 369 478 adults and followed them for a median of 4.7 years. A total of 4723 (1.28%) cardiovascular deaths occurred. After adjusting for the traditional risk factors, the hazard ratios for CIMT_mean per SD decreased with age, from 1.27 (95% CI, 1.17-1.37) in the 35 to 44 years age group to 1.14 (95% CI, 1.10-1.19) in the 65 to 75 years age group (P for interaction <0.01). Meanwhile, the net reclassification improvement indexes for CIMT_mean were attenuated with age, from 22.60% (95% CI, 15.56%-29.64%) in the 35 to 44 years age group to 7.00% (95% CI, -6.82% to 20.83%) in the 65 to 75 years age group. Similar results were found for maximum CIMT in all age groups. Conclusions CIMT may improve cardiovascular risk prediction in the young and middle-aged populations, rather than those aged ≥55 years.

Polarized tip-enhanced Raman spectroscopy at liquid He temperature in ultrahigh vacuum using an off-axis parabolic mirror

Tip-enhanced Raman spectroscopy (TERS) combines inelastic light scattering well below the diffraction limit down to the nanometer range and scanning probe microscopy and, possibly, spectroscopy. In this way, topographic and spectroscopic as well as single- and two-particle information may simultaneously be collected. While single molecules can now be studied successfully, bulk solids are still not meaningfully accessible. It is the purpose of the work presented here to outline approaches toward this objective. We describe a home-built, liquid helium cooled, ultrahigh vacuum TERS. The setup is based on a scanning tunneling microscope and, as an innovation, an off-axis parabolic mirror having a high numerical aperture of ∼0.85 and a large working distance. The system is equipped with a fast load-lock chamber, a chamber for the in situ preparation of tips, substrates, and samples, and a TERS chamber. Base pressure and temperature in the TERS chamber were ∼3 × 10-11 mbar and 15 K, respectively. Polarization dependent tip-enhanced Raman spectra of the vibration modes of carbon nanotubes were successfully acquired at cryogenic temperature. The new features described here including very low pressure and temperature and the external access to the light polarizations, thus the selection rules, may pave the way toward the investigation of bulk and surface materials.

Long-term cumulative high-sensitivity cardiac troponin T and mortality among patients with acute heart failure

AIMS

This study aimed to evaluate the cumulative high-sensitivity cardiac troponin T (hs-cTNT) from admission to 12 months after discharge and its association with mortality after 12 months among patients with acute heart failure (HF).

METHODS

We used data from the China Patient-Centered Evaluative Assessment of Cardiac Events Prospective Heart Failure Study (China PEACE 5p-HF Study), which enrolled patients hospitalized primarily for HF from 52 hospitals between 2016 and 2018. We included patients who survived within 12 months and had hs-cTNT data at admission (within 48 h of admission) and 1 and 12 months after discharge. To evaluate the long-term cumulative hs-cTNT, we calculated cumulative hs-cTNT levels and cumulative times of high hs-cTNT level. Patients were divided into groups according to the quartiles of cumulative hs-cTNT levels (Quartiles 1-4) and cumulative times of high hs-cTNT levels (0-3 times). Multivariable Cox models were constructed to examine the association of cumulative hs-cTNT with mortality during the follow-up period.

RESULTS

We included 1137 patients with a median age of 64 [interquartile range (IQR), 54-73] years; 406 (35.7%) were female. The median cumulative hs-cTNT level was 150 (IQR, 91-241) ng/L*month. Based on the cumulative times of high hs-cTNT levels, 404 (35.5%) patients were with zero time, 203 (17.9%) with one time, 174 (15.3%) with two times, and 356 (31.3%) with three times. During a median follow-up of 4.76 (IQR, 4.25-5.07) years, 303 (26.6%) all-cause deaths occurred. The increasing cumulative hs-cTNT level and cumulative times of high hs-cTNT level were independently associated with excess all-cause mortality. Compared with Quartile 1 group, Quartile 4 had the highest hazard ratio (HR) of all-cause mortality [4.14; 95% confidence interval (CI): 2.51-6.85], followed by Quartile 3 (HR: 3.35; 95% CI: 2.05-5.48) and Quartile 2 (HR: 2.47; 95% CI: 1.49-4.08) groups. Similarly, taking the patients with zero time of high hs-cTNT level as the reference, the HRs were 1.60 (95% CI: 1.05-2.45), 2.61 (95% CI: 1.76-3.87), and 2.86 (95% CI: 1.98-4.14) in patients who had one, two, and three times of high hs-cTNT level, respectively.

CONCLUSIONS

Elevated cumulative hs-cTNT from admission to 12 months after discharge was independently associated with mortality after 12 months among patients with acute HF. Repeated measurements of hs-cTNT after discharge may help monitor the cardiac damage and identify patients with high risk of death.

Long-Term Trajectories of High-Sensitivity C-Reactive Protein Level Among Patients with Acute Heart Failure

Background

Inflammation contributes to the progression of heart failure (HF). However, long-term inflammatory trajectories and their associations with outcomes in patients with acute HF remain unclear.

Methods

Data was obtained from the China Patient-Centered Evaluative Assessment of Cardiac Events Prospective Heart Failure Study, and high-sensitivity C-reactive protein (hsCRP) was used to reflect the inflammatory level. Only patients who survived over 12-month and had hsCRP data at admission, 1-, and 12-month after discharge were included. The latent class trajectory modeling was used to characterize hsCRP trajectories. Multivariable Cox regression models were used to explore the association between hsCRP trajectories and following mortality.

Results

Totally, 1281 patients with a median 4.77 (interquartile range [IQR]: 4.24-5.07) years follow-up were included. The median age was 64 years (IQR: 54-73 years); 453 (35.4%) were female. Four distinct inflammatory trajectories were characterized: persistently low (n = 419, 32.7%), very high-marked decrease (n = 99, 7.7%), persistently high (n = 649, 50.7%), and persistently very high (n = 114, 8.9%). Compared with the persistently low trajectory, the all-cause mortality was increased in a graded pattern in the persistently high (hazard ratio [HR]: 1.59, 95% confidence interval [CI]: 1.23-2.07) and persistently very high (HR: 2.56, 95% CI: 1.83-3.70) trajectories; nevertheless, the mortality was not significantly increased in very high-marked decrease trajectory (HR: 0.94, 95% CI: 0.57-1.54).

Conclusion

Four distinct inflammatory trajectories were identified among patients with acute HF who survived over 12-month. Patients with persistently high and very high trajectories had significantly higher mortality than those with the persistently low trajectory.

Hospital Variation of Spironolactone Use in Patients Hospitalized for Heart Failure in China-The China PEACE Retrospective Heart Failure Study

Background Although aldosterone antagonists improve outcomes in select individuals with heart failure and reduced ejection fraction, studies in the United States have raised concerns about underuse and overuse. Variations in the prescription of aldosterone antagonist in China are unknown. Methods and Results In the multicenter, hospital-based, retrospective China PEACE (China Patient-Centered Evaluative Assessment of Cardiac Events) study, we identified a nationally representative cohort of admissions for heart failure in a nationally representative sample of Chinese hospitals in 2015. Patients were classified into 1 of 3 groups according to their eligibility for spironolactone-"ideal" (left ventricular ejection fraction <40% and without contraindications), "contraindicated" (a documented contraindication, irrespective of left ventricular ejection fraction), and "uncertain-benefit" (all others). We measured hospital variation of spironolactone prescriptions at discharge in the "ideal" and "contraindicated" group and calculated the median odds ratio (MOR), a measure of institution-level variation for 2 individuals with similar characteristics discharged at 2 randomly selected hospitals. Hospital characteristics associated with spironolactone use were identified using multivariable linear regression model. Among 1222 ideal patients from 97 hospitals, the median rate of spironolactone prescription was 78.6% (interquartile range [IQR], 42.8%-89.6% [range, 0%-100%], MOR, 3.4 [95% CI, 2.7-4.0]) at discharge. Among 900 contraindicated patients from 83 hospitals, the median rate of spironolactone prescription was 30.0% (IQR, 9.1%-50.0% [range, 0%-100%], MOR, 3.1 [95% CI, 2.4-3.9]) at discharge. Hospitals with independent departments of cardiology and located in Eastern China were associated with a 38.0% (95% CI, 18.7-57.3; P<0.001) and a 14.6% (95% CI, 2.3%-26.9%; P=0.020) higher rate of spironolactone use for ideal patients. Conclusions In this national study of hospitals in China, the use of spironolactone among ideal patients and the inappropriate use of spironolactone among patients with contraindications was substantial, with rates that varied markedly by institution. Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT02877914.

Impact of Non-cardiac Comorbidities on Long-Term Clinical Outcomes and Health Status After Acute Heart Failure in China

Background

Individual non-cardiac comorbidities are prevalent in HF; however, few studies reported how the aggregate burden of non-cardiac comorbidities affects long-term outcomes, and it is unknown whether this burden is associated with changes in health status.

Aims

To assess the association of the overall burden of non-cardiac comorbidities with clinical outcomes and quality of life (QoL) in patients hospitalized for heart failure (HF).

Methods

We prospectively enrolled patients hospitalized for HF from 52 hospitals in China. Eight key non-cardiac comorbidities [diabetes, chronic renal disease, chronic obstructive pulmonary disease (COPD), anemia, stroke, cancer, peripheral arterial disease (PAD), and liver cirrhosis] were included, and patients were categorized into four groups: none, one, two, and three or more comorbidities. We fitted Cox proportional hazards models to assess the burden of comorbidities on 1-year death and rehospitalization.

Results

Of the 4,866 patients, 25.3% had no non-cardiac comorbidity, 32.2% had one, 22.9% had two, and 19.6% had three or more in China. Compared with those without non-cardiac comorbidities, patients with three or more comorbidities had higher risks of 1-year all-cause death [heart rate, HR 1.89; 95% confidence interval (CI) 1.48–2.39] and all-rehospitalization (HR 1.35; 95%CI 1.15–1.58) after adjustment. Although all patients with HF experienced a longitudinal improvement in QoL in the 180 days after discharge, those with three or more non-cardiac comorbidities had an unadjusted 11.4 (95%CI −13.4 to −9.4) lower Kansas City Cardiomyopathy Questionnaire (KCCQ) scores than patients without comorbidities. This difference decreased to −6.4 (95%CI −8.6 to −4.2) after adjustment for covariates.

Conclusion

Among patients hospitalized with HF in this study, a higher burden of non-cardiac comorbidities was significantly associated with worse health-related QoL (HRQoL), increased risks of death, and rehospitalization post-discharge. The findings highlight the need to address the management of comorbidities effectively in standardized HF care.

Multi-Biomarker Points and Outcomes in Patients Hospitalized for Heart Failure: Insights From the China PEACE Prospective Heart Failure Study

Objective

To quantitatively characterize the pattern of systemic impairment reflected by conventional biomarkers and assess how it relates to clinical outcomes and quality of life among patients hospitalized for heart failure (HF).

Methods

Patients hospitalized for HF from 52 hospitals in China were enrolled between 2016 and 2018. They were divided into developing and validating cohorts; the developing cohort was used for calculating the weights of biomarkers and constructing the multi-biomarker panel, while the validating one was used for evaluating the relationship between multi-biomarker points and outcomes. In total, five conventional biomarkers reflecting various pathophysiological processes were included in the panel: N-terminal pro-B type natriuretic peptide, high-sensitivity troponin T, hemoglobin, albumin, and creatinine. The weights of the biomarkers were defined based on their relationship with cardiovascular death, and each patient had a multi-biomarker point ranging from 0 to 12. The primary clinical outcome was cardiovascular death, and the other clinical outcomes included rehospitalization for HF, all-cause death, and all-cause rehospitalization in 1-year. The quality of life was measured using Kansas City Cardiovascular Questionnaire. Multi-variable Cox proportional hazard models were used to assess the risks of clinical outcomes, and generalized linear models were used to evaluate the quality of life.

Results

In total, 4,693 patients hospitalized for HF were included in this analysis; the median (interquartile range, IQR) age was 67 (57-75) years old and 1,763 (37.6%) were female. The median multi-biomarker point was 5 (IQR, 2-6). There were 18.0% of patients in the low point group (<2), 29.4% in the mid-low point group (2-4), 27.8% in the mid-high point group (5-6), and 24.7% in the high point group (>6). Compared with those in the low point group, the patients in the high point group had a significantly excess risk of cardiovascular death (adjusted hazard ratio: 5.69, 95% CI, 3.33-9.70). Furthermore, patients with higher points were also more prone to worse quality of life.

Conclusion

Systemic impairment reflected by abnormal conventional biomarker values was common amongst patients hospitalized for HF and had substantially cumulative adverse influence on clinical outcomes and quality of life.

Analysing neutron radiation damage in YBa2 Cu3 O7-x high temperature superconductor tapes

Superconducting windings will be necessary in future fusion reactors to generate the strong magnetic fields needed to confine the plasma, and these superconducting materials will inevitably be exposed to neutron damage. It is known that this exposure results in the creation of isolated damage cascades, but the presence of these defects alone is not sufficient to explain the degradation of macroscopic superconducting properties and a quantitative method is needed to assess the subtle lattice damage in between the clusters. We have studied REBCO coated conductors irradiated with neutrons to a cumulative dose of 3.3×10²²  n*m^-2  that show a degradation of both T_c  and J_c values, and use HRTEM analysis to show that this irradiation introduces ∼10 nm amorphous collision cascades. In addition we introduce a new method for the analysis of these images to quantify the degree of lattice disorder in the apparently perfect matrix between these cascades. This method utilises Fast Fourier and Discrete Cosine Transformations of a statistically-relevant number of HRTEM images of pristine, neutron-irradiated, and amorphous samples, and extracts the degree of randomness in terms of entropy values. Our results show that these entropy values in both mid-frequency band FFT and DCT domains correlate with the expected level of lattice damage, with the pristine samples having the lowest and the fully amorphous regions the highest entropy values.  Our methodology allows us to quantify 'invisible' lattice damage to and correlate these values to the degradation of superconducting properties, and also has relevance for a wider range of applications in the field of electron microscopy where small changes in lattice perfection need to be measured. This article is protected by copyright. All rights reserved.

Health Status Predicts Short- and Long-Term Risk of Composite Clinical Outcomes in Acute Heart Failure

OBJECTIVES

This study aims to examine the association between the Kansas City Cardiomyopathy Questionnaire (KCCQ)-12 score and the 30-day and 1-year rates of composite events of cardiovascular death and heart failure (HF) rehospitalization in patients with acute HF.

BACKGROUND

Few studies reported the prognostic effects of KCCQ in acute HF.

METHODS

This study prospectively enrolled adult patients hospitalized for HF from 52 hospitals in China and collected the KCCQ-12 score within 48 hour of index admission. The study used multivariable Cox regression to examine the association between KCCQ-12 score and 30-day and 1-year composite events and was further stratified by new-onset HF and acutely decompensated chronic heart failure (ADCHF). Subgroup analyses were performed to explore the potential heterogeneity. The study evaluated the incremental prognostic value of KCCQ-12 score over N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and established risk scores by C-statistics, net reclassification improvement, and integrated discrimination improvement.

RESULTS

Among 4,898 patients, 29.4% had new-onset HF. After adjustment, each 10-point decrease in the KCCQ-12 score was associated with a 13% increase in 30-day risk and a 7% increase in 1-year risk. The associations were consistent regardless of new-onset HF or ADCHF, age, sex, left ventricular ejection fraction, New York Heart Association functional class, NT-proBNP level, comorbidities, and renal function. Adding KCCQ-12 score to NT-proBNP and established risk scores significantly improved prognostic capabilities measured by C-statistics, net reclassification improvement, and integrated discrimination improvement.

CONCLUSIONS

In acute HF, a poor KCCQ-12 score predicted short- and long-term risks of cardiovascular death and HF rehospitalization. KCCQ-12 could serve as a convenient tool for rapid initial risk stratification and provide additional prognostic value over NT-proBNP and established risk scores.

[Mn2+-doped Prussian blue nanoparticles for T1-T2 dual-mode magnetic resonance imaging and photothermal therapy in vitro]

OBJECTIVE

To prepare Mn²⁺-doped Prussian blue nanoparticles (Mn-PB NPs) for T1-T2 dual-mode magnetic resonance imaging (MRI) and photothermal therapy in vitro.

OBJECTIVE

Mn-PB NPs were prepared based on manganese chloride, ferrous chloride and potassium ferricyanide using the microemulsion method. The performance of T1-T2 dual-mode MRI with Mn-PB NPs and the photothermal property of the nanoparticles were assessed. CCK-8 assay and AM/PI double staining were used to evaluate the effect of photothermal therapy in vitro using the parepared nanoparticles.

OBJECTIVE

The prepared Mn-PB NPs had a mean particle size of 39.46±0.42 nm with a Zeta potential of -25.9±1.2 mV and exhibited a good dispersibility and uniform particle size. In MRI using the nanoparticles, the r1 and r2 values reached 0.68 and 3.65 (mmol/L)^-1s^-1, respectively, indicating good performance of Mn-PB NPs for T1 and T2 enhancement in MRI. When irradiated with 808 nm laser for 10 min, Mn-PB NPs showed a temperature rise to 90 ℃ to cause significant reduction of cell survival. CCK-8 assay and AM/PI double staining confirmed that Mn-PB NPs were capable of efficient killing of HepG2 cells upon 808 nm laser irradiation.

OBJECTIVE

The Mn-PB NPs prepared in this work have uniform particle size and show good performances both in MRI for T1 and T2 enhancement and in photothermal therapy in vitro without obvious cytotoxicity.

Histological analysis of spermatogenesis and the germ cell seasonal development within the testis of domesticated tree shrews (Tupaia belangeri chinensis)

This study aimed to address the lack of information on the male germ cell seasonal development of domesticated tree shrews (Tupaia belangeri chinensis). Testicular tissues were collected from 60 tree shrews (n=5 per month). The ultrastructures of the testes and spermatids were examined via transmission electron microscopy. Apoptosis of spermatogenic cells was measured through terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The expression of proliferation factors, namely, proliferating cell nuclear antigen (PCNA) and Ki67, in testicular tissues was assayed through immunohistochemistry. Spermatids ultrastructure showed seasonal differences, and spermatogenesis was relatively active in June and July and relatively stagnant from October to November. The percentage of TUNEL-positive germ cells was less during October and November, while greater in July than other phases. The number of PCNA-nucleus-positive germ cells was most in June and July, but with cytoplasm staining from October to November. Ki67 presented positive expression in the testes from April to September, with highest expression in June, but with no expression from October to March. In summary, there are seasonal differences in tissue morphology related to spermatogenesis in domesticated tree shrews. PCNA expression and Ki67 expression are good indicators of seasonal differences in male germ cells.

Are medical record front page data suitable for risk adjustment in hospital performance measurement? Development and validation of a risk model of in-hospital mortality after acute myocardial infarction

OBJECTIVES

To develop a model of in-hospital mortality using medical record front page (MRFP) data and assess its validity in case-mix standardisation by comparison with a model developed using the complete medical record data.

DESIGN

A nationally representative retrospective study.

SETTING

Representative hospitals in China, covering 161 hospitals in modelling cohort and 156 hospitals in validation cohort.

PARTICIPANTS

Representative patients admitted for acute myocardial infarction. 8370 patients in modelling cohort and 9704 patients in validation cohort.

PRIMARY OUTCOME MEASURES

In-hospital mortality, which was defined explicitly as death that occurred during hospitalisation, and the hospital-level risk standardised mortality rate (RSMR).

RESULTS

A total of 14 variables were included in the model predicting in-hospital mortality based on MRFP data, with the area under receiver operating characteristic curve of 0.78 among modelling cohort and 0.79 among validation cohort. The median of absolute difference between the hospital RSMR predicted by hierarchical generalised linear models established based on MRFP data and complete medical record data, which was built as 'reference model', was 0.08% (10th and 90th percentiles: -1.8% and 1.6%). In the regression model comparing the RSMR between two models, the slope and intercept of the regression equation is 0.90 and 0.007 in modelling cohort, while 0.85 and 0.010 in validation cohort, which indicated that the evaluation capability from two models were very similar.

CONCLUSIONS

The models based on MRFP data showed good discrimination and calibration capability, as well as similar risk prediction effect in comparison with the model based on complete medical record data, which proved that MRFP data could be suitable for risk adjustment in hospital performance measurement.

Remote Mesoscopic Signatures of Induced Magnetic Texture in Graphene

Mesoscopic conductance fluctuations are a ubiquitous signature of phase-coherent transport in small conductors, exhibiting universal character independent of system details. In this Letter, however, we demonstrate a pronounced breakdown of this universality, due to the interplay of local and remote phenomena in transport. Our experiments are performed in a graphene-based interaction-detection geometry, in which an artificial magnetic texture is induced in the graphene layer by covering a portion of it with a micromagnet. When probing conduction at some distance from this region, the strong influence of remote factors is manifested through the appearance of giant conductance fluctuations, with amplitude much larger than e^{2}/h. This violation of one of the fundamental tenets of mesoscopic physics dramatically demonstrates how local considerations can be overwhelmed by remote signatures in phase-coherent conductors.

Raman Study of Cooper Pairing Instabilities in (Li_{1-x}Fe_{x})OHFeSe

We studied the electronic Raman spectra of (Li_{1-x}Fe_{x})OHFeSe as a function of light polarization and temperature. In the B_{1g} spectra alone we observe the redistribution of spectral weight expected for a superconductor and two well-resolved peaks below T_{c}. The nearly resolution-limited peak at 110  cm^{-1} (13.6 meV) is identified as a collective mode. The peak at 190  cm^{-1} (23.6 meV) is presumably another collective mode since the line is symmetric and its energy is significantly below the gap energy observed by single-particle spectroscopies. Given the experimental band structure of (Li_{1-x}Fe_{x})OHFeSe, the most plausible explanations include conventional spin-fluctuation pairing between the electron bands and the incipient hole band and pairing between the hybridized electron bands. The absence of gap features in A_{1g} and B_{2g} symmetry favors the second case. Thus, in spite of various differences between the pnictides and chalcogenides, this Letter demonstrates the proximity of pairing states and the importance of band structure effects in the Fe-based compounds.

Universal scaling of weak localization in graphene due to bias-induced dispersion decoherence

The differential conductance of graphene is shown to exhibit a zero-bias anomaly at low temperatures, arising from a suppression of the quantum corrections due to weak localization and electron interactions. A simple rescaling of these data, free of any adjustable parameters, shows that this anomaly exhibits a universal, temperature- (T) independent form. According to this, the differential conductance is approximately constant at small voltages (V < kBT/e), while at larger voltages it increases logarithmically with the applied bias. For theoretical insight into the origins of this behaviour, which is inconsistent with electron heating, we formulate a model for weak-localization in the presence of nonequilibrium transport. According to this model, the applied voltage causes unavoidable dispersion decoherence, which arises as diffusing electron partial waves, with a spread of energies defined by the value of the applied voltage, gradually decohere with one another as they diffuse through the system. The decoherence yields a universal scaling of the conductance as a function of eV/kBT, with a logarithmic variation for eV/kBT > 1, variations in accordance with the results of experiment. Our theoretical description of nonequilibrium transport in the presence of this source of decoherence exhibits strong similarities with the results of experiment, including the aforementioned rescaling of the conductance and its logarithmic variation as a function of the applied voltage.

Effects of wet atmospheric nitrogen deposition on epiphytic lichens in the subtropical forests of Central China: Evaluation of the lichen food supply and quality of two endangered primates

Over the last few decades, the threat posed to biodiversity and ecosystem function by atmospheric nitrogen (N) deposition has been increasingly recognized. The disturbed nutrient balance and species composition of plants induced by higher N deposition can impact the biodiversity of the organisms that consume the plants. In this research, we implemented several experiments to estimate the effects of increased N deposition on the growth, survival, and nutrients of the dominant epiphytic lichens in the subtropical mountains in Central China to assess the lichen food amount and nutritional quality for two endangered primates endemic to China. Our results indicated that the thallus growth and propagule survival of the lichens were significantly decreased when nitrogen addition changed from 6.25 to 50.0 kg N·ha^-1·y^-1; it was also shown that lichen biomass could be decreased by 11.2%-70.2% when the deposition addition exceeded 6.25 kg N·ha^-1·y^-1. Further, our study revealed that increased nitrogen deposition also reduced the nutritional quality of the lichens via reducing the soluble protein and soluble sugar levels and increasing the fiber content, which would substantially affect the diet selection of the plants consumers in the region, particularly the populations of the two lichen-eating endangered primate species, Rhinopithecus roxellana and R. bieti. Our experimental study suggested that the nitrogen pollution derived from anthropogenic activities could cause cascading effects for the whole forest ecosystem of Central China; thus, more studies about nitrogen deposition in this region are required.

Isolation of H8N4 avian influenza virus from wild birds in Shanghai, China

The H8 subtype viruses are rarely isolated from wild ducks. Shanghai is one of the important wintering or stopover sites on the East Asia-Australia Migration Flyway. An influenza virus, subtype H8N4, was firstly isolated from a common teal (Anas crecca) in Shanghai during 2017-2018 in this study. To clarify the genetic characteristics of the H8N4 virus, the whole genome sequences were analyzed. Phylogenetic analysis of the hemagglutinin and neuraminidase genes showed that they shared highest nucleotide identity (99.19%-99.64%) with the Japan duck-origin H8N4 virus collected in 2016 (A/duck/Aichi/231003/2016) and belonged to the Eurasian-like avian lineage. Six other genes of the H8N4 isolated virus were all highly similar to the corresponding genes of a wide range of AIV subtypes including H9N2, H5N7, H3N8, H1N2, H4N6 and H1N1. The results indicated that the H8N4 virus was a multiple reassortant virus. The study emphasized that the continuous surveillance of influenza virus in wild birds should be strengthened. Keywords: avian influenza virus; H8N4; phylogenetic analysis; Shanghai.

Semi-dominant mutation in the cysteine-rich receptor-like kinase gene, ALS1, conducts constitutive defence response in rice

Plants have evolved a sophisticated two-branch defence system to prevent the growth and spread of pathogen infection. The novel Cys-rich repeat (CRR) containing receptor-like kinases, known as CRKs, were reported to mediate defence resistance in plants. For rice, there are only two reports of CRKs. A semi-dominant lesion mimic mutant als1 (apoptosis leaf and sheath 1) in rice was identified to demonstrate spontaneous lesions on the leaf blade and sheath. A map-based cloning strategy was used for fine mapping and cloning of ALS1, which was confirmed to be a typical CRK in rice. Functional studies of ALS1 were conducted, including phylogenetic analysis, expression analysis, subcellular location and blast resistance identification. Most pathogenesis-related (PR) genes and other defence-related genes were activated and up-regulated to a high degree. ALS1 was expressed mainly in the leaf blade and sheath, in which further study revealed that ALS1 was present in the vascular bundles. ALS1 was located in the cell membrane of rice protoplasts, and its mutation did not change its subcellular location. Jasmonic acid (JA) and salicylic acid (SA) accumulation were observed in als1, and enhanced blast resistance was also observed. The mutation of ALS1 caused a constitutively activated defence response in als1. The results of our study imply that ALS1 participates in a defence response resembling the common SA-, JA- and NH1-mediated defence responses in rice.

Etching gas-sieving nanopores in single-layer graphene with an angstrom precision for high-performance gas mixture separation

One of the bottlenecks in realizing the potential of atom-thick graphene membrane for gas sieving is the difficulty in incorporating nanopores in an otherwise impermeable graphene lattice, with an angstrom precision at a high-enough pore density. We realize this design by developing a synergistic, partially decoupled defect nucleation and pore expansion strategy using O₂ plasma and O₃ treatment. A high density (ca. 2.1 × 10¹² cm^-2) of H₂-sieving pores was achieved while limiting the percentage of CH₄-permeating pores to 13 to 22 parts per million. As a result, a record-high gas mixture separation performance was achieved (H₂ permeance, 1340 to 6045 gas permeation units; H₂/CH₄ separation factor, 15.6 to 25.1; H₂/C₃H₈ separation factor, 38.0 to 57.8). This highly scalable pore etching strategy will accelerate the development of single-layer graphene-based energy-efficient membranes.

[The treatment of nose-eye correlated diseases with external nasal incision combined with nasal cavity approach surgery through endoscope]

Objective:To explore the indications and characteristics for the treatment of nose-eye correlated diseases with endoscopic surgery through external nasal incision combined with nasal cavity approach.Method:The clinical data of 13 patients whom hospitalized in our department and treated by endoscopic surgery through external nasal incision combined with nasal cavity approach since October 2011, were retrospectively analyzed and the characteristics of different pathological changes, clinical manifestations, surgical approach and follow-up results were summarized.Four cases of patients underwent endoscopic surgery through nasal cavity and lacrimal caruncle conjunctival incision, 4 cases received bone fracture reduction and DCR with endoscope through double path of nasal cavity and the original trauma wound, 2 cases with endoscopic bone tumor resection through nasal cavity and external nasal incision, the rest of the 3 cases with endonasal endoscopic and peri-orbit incision surgery.Result:Two cases of tumor patients showed no recurrence followed up for 1.5 to 2 years; the diplopia disappeared in 2 cases of orbital medial wall fracture; surgeries of 4 cases of orbital wall fracture with lacrimal duct obstruction patients, 3 cases succeeded, 1 case failed and change into dacryocystorhinotomy with external nasal incision, and epiphora of all patients vanished; all of the patients of sinus osteoma, foreign bodies and abscess were cured and symptoms disappeared; the symptoms of ectopic meningioma patient gradually died down with eyebrow scars left.Conclusion:The surgery with external nasal incision combined with nasal cavity approach through endoscope to treat noseeye correlated diseases can effectively deal with relevant pathological changes, with the advantages of clear operation field and less damage, but its exact indications and surgical methods still need to be further explored.

Total synthesis of teixobactin and its stereoisomers

The total syntheses of teixobactin and a series of its stereoisomers at positions 2, 5, 6, 10 and 11 were achieved via a combined strategy of solution and solid phase peptide synthesis.

High throughput in vitro and in vivo screening of inland waters of Southern California

The impact of unmonitored contaminants, also known as contaminants of emerging concern (CECs), on freshwater streams remains largely uncharacterized. Water samples from 31 streams representing urban, agricultural and undeveloped (i.e., open space) land use in Southern California (USA) were analyzed for in vitro and in vivo bioactivity. The extent and magnitude of bioactivity screened using endocrine-responsive cell bioassays and a fish embryo screening assay were low. In contrast, a wider gradient of responses for the aryl hydrocarbon receptor (AhR) assay was observed, which was negatively correlated with a measure of benthic community structure. Both aromatic and non-aromatic CECs were tentatively identified in these samples, but polycyclic aromatic hydrocarbons (PAHs), known AhR agonists in urban environments, were not present at detectable levels. These results suggest that a combination of in vitro and in vivo show potential as screening techniques for biological condition in situ, but that more advanced, comprehensive analytical methods are needed to identify bioactive contaminants.

[The study of locating facial nerve precisely in middle ear surgery based on clinical anatomy]

Objective:To investigate the methods of locating facial nerve precisely in middle ear surgery through the observation and measurement of the facial nerve and surrounding anatomical structures and to provide reference for the middle ear surgery.Method:Combined surgical approach on 15 cases (30 sides) fresh adult cadaveric specimens were dissected, observed the characteristics of facial nerve and its shape and spatial relationship of the surrounding structures, and measured the distance between the facial nerve and its surrounding structures.Result:The shortest distance from the midpoint of the posterior wall of external auditory canal (annulus level) to the vertical segment of the facial nerve was (3.37±0.34)mm, the shortest distance from the leading edge of the sigmoid sinus to the vertical segment of facial nerve was (7.40±0.71)mm, the shortest distance from the lateral margin of jugular bulb to the facial nerve was (5.58±0.79)mm, the shortest distance from Henle crest to the pyramidal segment of facial nerve was (12.76±1.24)mm, the shortest distance between the pyramidal segment of facial nerve and the posterior short limb of incus was (1.56±0.35)mm, the shortest distance between the pyramidal segment of facial nerve and the lower edge of posterior semicircular canal was (2.56±0.41) mm, the shortest distance between the lower edge of horizontal semicircular canal and the horizontal segment of facial nerve was (1.28±0.32) mm, the shortest distance between the upper edge of vestibular window and the horizontal segment of facial nerve was (0.67±0.15)mm.Conclusion:A good command of the anatomy of temporal bone as well as the methods of locating facial nerve will provide the key to reduce the probability of iatrogenic facial nerve injury in middle ear surgery.

Contrast-enhanced ultrasound in the diagnosis of orbital space-occupying lesions

AIM

To summarise the sonographic findings and assess the feasibility of contrast-enhanced ultrasound (CEUS) as an imaging method for the diagnosis of orbital space-occupying lesions.

MATERIALS AND METHODS

This was a prospective study of 53 patients who underwent orbital ultrasound at Xijing Hospital. Two-dimensional ultrasound, colour Doppler flow imaging (CDFI), and CEUS imaging were obtained and compared in patients with orbital haemangioma, pseudotumour, melanoma of the choroid, and retinoblastoma.

RESULTS

CEUS imaging cannot only visualise the location, shape, border, acoustic properties of a lesion, and interactions between the lesion and surrounding tissues, but also display the microvasculature and tissue perfusion within the lesion. The information obtained from CEUS imaging is valuable for diagnosis and differential diagnosis of orbital space-occupying lesions.

CONCLUSION

CEUS imaging allowed better visualisation of the lesions, enabled detection of vascular changes, increased the signal-to-noise ratio, and increased the sensitivity of detection of changes in perfusion in the microcirculation. It has relatively high sensitivity and specificity in the diagnosis of orbital space-occupying lesions and increases the accuracy of diagnosis.

Tumour-activated liver stromal cells regulate myeloid-derived suppressor cells accumulation in the liver

Regulating mechanisms underlying hepatic myeloid-derived suppressor cell (MDSC) accumulation remain to be described. Here, we provide evidence for the involvement of tumour-activated liver stromal cells in the process of hepatic MDSCs migration and accumulation. Our data showed an elevated frequency of MDSCs in the liver of tumour-bearing mice. Moreover, tumour-activated liver stromal cells promote MDSC migration into the liver site. Further investigation indicated higher levels of cytokine and chemokine expression in liver stromal cells after exposure to the tumour-conditioned supernatant. Notably, the expression levels of proinflammatory factors, mainly including macrophage colony stimulating factor (M-CSF), transforming growth factor-β (TGF-β), monocyte chemotactic protein-1 (MCP-1) and stromal-derived factor-1 (SDF-1), increased after treatment with tumour-conditioned supernatant, and blockade of MCP-1 or SDF-1 decreased the proportion of tumour infiltrated MDSCs in mice co-transplanted with liver stromal cells and tumour cells, but not in mice with only tumour cells injection. These findings demonstrate that tumour-activated liver stromal cells produce higher levels of chemokines and cytokines, which may contribute to MDSC accumulation into the liver site in patients with liver cancer.

Simultaneous detection of 45 fusion genes in leukemia by dual-color fluorescence real-time PCR

INTRODUCTION

Detection of recurrent genetic abnormalities is of great significance for a refined diagnosis and assessment of prognosis in leukemia. Conventional nested reverse transcription PCR is labor intensive and time-consuming.

METHODS

We have developed a novel dual-color TaqMan probe-based real-time PCR method for the simultaneous screening of 45 fusion transcripts in 12 parallel reactions. The method was tested and validated with cell lines carrying known fusion transcripts and patient samples.

RESULTS

A multiplex real-time PCR method was successfully developed for rapid detection of 45 fusion genes and validated for 15 of the more commonly detected fusion genes. Intra-assay reproducibility assessed for the most frequent rearrangements ranged from 0.41% to 0.74% for the coefficient of variation (CV) of cycle threshold (Ct) and the interassay reproducibility ranged from 1.62% to 2.83% in five separate experiments. The lowest detection limit for the translocations tested ranged between 1 : 16 000 and 1 : 32 000. Validation of the method with 213 patient samples showed 100% specificity and excellent consistence with conventional nested RT-PCR.

CONCLUSION

Overall, we believe that this method is easily applicable, cost-effective, and clinically useful for a rapid screening of fusion genes in the initial diagnostic phase of leukemia. Its use can also be extended to the monitoring of minimal residual disease.

[Endonasal endoscopic surgery in treatment of medial recus muscle entrapment: the management and effectiveness]

Objective:To explore the indications , surgery method and effect for the treatment of medial rectus muscle entrapment with endoscopic surgery.Method: Eight medial rectus muscle entrapment patients were enrolled in this study,3 cases underwent obital medial wall fracture reposition and medial rectus muscle adhesion decomposition surgery through endonasal endoscope,and 5 cases received obital medial wall fracture reposition surgery with endoscope through nasal cavity and lacrimal caruncle conjunctival incision. Result:The diplopia disappeared and eyeball abduction function recovered in 6 cases of medial rectus muscle entrapment patients within 2 months,and 1 case with each surgery had mild diplopia and eyeball incomplete abduction left.Conclusion:Adopting endonasal endoscopic surgery or dual approaches surgery with endonasal endoscopic and transcaruncular surgery were ideal methods for medial rectus muscle entrapment diseases.Surgery with endoscope has the characteristics of clear field and less damage.The surgery should be performed whithin 3 weeks, and the entrapment of medial rectus muscle can be resoved effectively.

Thermally Assisted Nonvolatile Memory in Monolayer MoS2 Transistors

We demonstrate a novel form of thermally-assisted hysteresis in the transfer curves of monolayer MoS₂ FETs, characterized by the appearance of a large gate-voltage window and distinct current levels that differ by a factor of ∼10². The hysteresis emerges for temperatures in excess of 400 K and, from studies in which the gate-voltage sweep parameters are varied, appears to be related to charge injection into the SiO₂ gate dielectric. The thermally-assisted memory is strongly suppressed in equivalent measurements performed on bilayer transistors, suggesting that weak screening in the monolayer system plays a vital role in generating its strongly sensitive response to the charge-injection process. By exploiting the full features of the hysteretic transfer curves, programmable memory operation is demonstrated. The essential principles demonstrated here point the way to a new class of thermally assisted memories based on atomically thin two-dimensional semiconductors.

[Outcomes of total deafness type of idiopathic suddendeafness in different ages]

Objective:This retrospective study was aimed to investigate the characteristics of hearing recovery in the complete deafness type of SSNHL(≥81 dBHL) in patients with different ages.Method:Clinical outcomes of 179 total deafness type of idiopathic sudden deafness were compared.Patients were divided into 5 groups according to age,they were,pediatric group(13 years or less),youthful group(14-44 years),middle-aged group(45-59 years),presenium group(60-74 years),senectitude group(75 years or higher).Patients were divided into 3 groups according to the initial degree of hearing loss: 81 dB group (81-89 dBHL),90 dB group(90- 99 dBHL),100 dB group(100 dBHL or higher).Routine comprehensive treatment including corticosteroids,the inner ear microcirculation improvement drugs,neurotrophic drugs,saturationoxygen and hyperbaric oxygen therapy,etc.was applied.Patients were treated in accordance with the age and body weight.Result:The percentage of youthful group(83/179,46.4%) was highest(P<0.05),middle-aged group(57/179,31.8%)followed(P<0.05),presenium group(26/179,14.5%)was lower(P<0.05),pediatric group(8/179,4.5%) and senectitude group(5/179,2.8%)were the lowest.No a complete recovery in either pediatric group or senectitude group.A complete recovery was rare in the other groups.Recovery rate of the different aged groups was similar(P>0.05).The percentage of 100 dB group(108/179,60.3%) was highest(P<0.05).The percentage of 81 dB group(39/179,21.8%)was similar to 90 dB group(32/179,17.9%)(P>0.05).Recovery rate was similar in 81 dB group(25/39,64.1%)and 90 dB group(18/32,56.2%)(P>0.05).Recovery rate of both 81 dB group and 90 dB group were greater than 100 dB group(24/108,22.2%)(P<0.05).The 100 dB group reduced the satisfactory recovery effects.There were no differences in the proportion of the patients with dizziness(95/179,53.1%)and without dizziness(84/179,46.9%)(P>0.05).Recovery rate of patients without dizziness(43/84,51.2%) was greater than with dizziness(24/95,25.3%)(P<0.05).The percentage of the patients without dizziness(31/39,79.5%)in 81 dB group was the highest(P<0.05),90 dB group(18/32,56.2%)followed(P<0.05).The percentage of the patients with dizziness in 100 dB group(73/108,67.6%)was highest(P<0.05).Recovery rate was similar in the patients without dizziness of 81 dB group(21/31,67.7%)and 90 dB group(11/18,61.1%)(P>0.05).Recovery rate of the above two groups was greater than that of 100 dB group(11/35,31.4%)(P<0.05).Conclusion:Recovery rate of the different aged groups was similar.The percentage of the patients with dizziness in 100 dB group was highest.Initial hearing threshold in excess of 100 dB reduced the satisfactory recovery in patients with total deafness type of SSNHL.Our results provided a good reference for other clinicians.

Tristetraprolin: a novel mediator of the anticancer properties of resveratrol

Resveratrol is a natural compound that exhibits anticancer properties. Previous studies have proved that it can inhibit the proliferation of breast cancer cell lines and upregulate some cytokines such as cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF). The initiation and progression of cancer are associated with the abnormal expression of multiple cytokines. Tristetraprolin (TTP), an mRNA-binding protein, is one of the key proteins that participate in regulating cytokine expression. Two different proliferation assays on MCF-7 cells showed that the cell proliferation rate significantly reduced following treatment with resveratrol. Most importantly, we found that resveratrol promoted TTP expression at both the mRNA and protein level in a dose- and time-dependent manner. In addition, the expression of COX-2 and VEGF were significantly suppressed by resveratrol while that of inducible nitric oxide synthase (iNOS) was upregulated. Lastly, the effects of resveratrol on both MCF-7 proliferation and expression of COX-2, VEGF, and iNOS were significantly inhibited by TTP knockdown, indicating that TTP mediates the anticancer properties of resveratrol. In summary, we conclude that resveratrol inhibits the proliferation of MCF-7 cells by TTP upregulation, which is associated with downregulation of COX-2 and VEGF and upregulation of iNOS.

"Freeing" Graphene from Its Substrate: Observing Intrinsic Velocity Saturation with Rapid Electrical Pulsing

Rapid (nanosecond-scale) electrical pulsing is used to study drift-velocity saturation in graphene field-effect devices. In these experiments, high-field pulses are utilized to drive graphene's carriers on time scales much faster than that on which energy loss to the underlying substrate can occur, thereby allowing the observation of the highest saturation velocities reported to date. In a dramatic departure from the behavior exhibited by conventional metals and semiconductors, as the electron or hole density is reduced toward the charge-neutrality point, the drift velocity is found to reach values comparable to the Fermi velocity itself. Corresponding current densities are as large as 10(9) A/cm(2), similar to the values reported for carbon nanotubes and for graphene-on-diamond transistors. In essence, our approach of rapid pulsing allows us to "free" graphene from the deleterious influence of its substrate, revealing a pathway to achieve the superior electrical performance promised by this material. The usefulness of this approach is not merely limited to graphene but should extend also to a broad variety of two-dimensional semiconductors.

Block copolymer synthesis by controlled/living radical polymerisation in heterogeneous systems

We review the range of CLRP-controlled syntheses of block copolymer particles in dispersed systems, which are being exploited to create new opportunities for the design of nanostructured soft materials.

Palladium-catalyzed arylation of β-methylene C(sp3)–H bonds at room temperature: desymmetrization of simple cycloalkyl carboxylic acids

A new protocol for Pd-catalyzed β methylene C–H arylation of N-quinolyl cycloalkylcarboxamides with aryl iodides at room temperature is reported.