Investigation on Mechanism of Microstructure Evolution during Multi-Process Hot Forming of GH4169 Superalloy Forging

Typically, in the manufacturing of GH4169 superalloy forgings, the multi-process hot forming that consists of pre-deformation, heat treatment and final deformation is required. This study focuses on the microstructural evolution throughout hot working processes. Considering that δ phase can promote nucleation and limit the growth of grains, a process route was designed, including pre-deformation, aging treatment (AT) to precipitate sufficient δ phases, high temperature holding (HTH) to uniformly heat the forging, and final deformation. The results show that the uneven strain distribution after pre-deformation has a significant impact on the subsequent refinement of the grain microstructure due to the complex coupling relationship between the evolution of the δ phase and recrystallization behavior. After the final deformation, the fine-grain microstructure with short rod-like δ phases as boundaries is easy to form in the region with a large strain of the pre-forging. However, necklace-like mixed grain microstructure is formed in the region with a small strain of the pre-forging. In addition, when the microstructure before final deformation consists of mixed grains, dynamic recrystallization (DRX) nucleation behavior preferentially depends on kernel average misorientation (KAM) values. A large KAM can promote the formation of DRX nuclei. When the KAM values are close, a smaller average grain size of mixed-grain microstructure is more conductive to promote the DRX nucleation. Finally, the interaction mechanisms between δ phase and DRX nucleation are revealed.

Effects of Aging Treatment on the Microstructures and Mechanical Properties of a TC18 Alloy

In the present work, the effects of aging treatment on the microstructures of a TC18 alloy are studied. The influence of aging treatment on the tensile properties and failure mechanisms is systematically analyzed. It is found that the size and morphology of the primary α (αp) phases are insensitive to aging temperature and time. Furthermore, the aging temperature and time dramatically influence the precipitation of the secondary α (αs) phases. Massive αs phases precipitate and gradually coarsen, and finally weave together by increasing the aging temperature or extending the aging time. The variations in αp and αs phases induced by aging parameters also affect the mechanical properties. Both yield strength (YS) and ultimate tensile strength (UTS) first increase and then decrease by increasing the aging temperature and time, while ductility first decreases and then increases. There is an excellent balance between the strengths and ductility. When the aging temperature is changed from 450 to 550 °C, YS varies from 1238.6 to 1381.6 MPa, UTS varies from 1363.2 to 1516.8 MPa, and the moderate elongation ranges from 9.0% to 10.3%. These results reveal that the thickness of αs phases is responsible for material strengths, while the content of α phases can enhance material ductility. The ductile characteristics of the alloy with coarser αs phases are more obvious than those with thinner αs phases. Therefore, the aging treatment is helpful for the precipitation and homogeneous distribution of αs phases, which are essential for balancing the strengths and ductility of the studied Ti alloy.

Comparison of contrast-enhanced ultrasonography and MRI results obtained by expert and novice radiologists indicating short-term response after transarterial chemoembolisation for hepatocellular carcinoma

AIM

To evaluate inter-reader agreement between novice and expert radiologists in assessing contrast-enhanced ultrasonography (CEUS) and magnetic resonance imaging (MRI) images for detecting viable tumours with different sizes after conventional transarterial chemoembolisation (cTACE).

MATERIALS AND METHODS

This prospective study included patients who had less than five hepatomas and who underwent cTACE. Hepatomas with one or two feeding arteries were selected as target lesions. CEUS and MRI were performed within 1 week after cTACE to evaluate viable tumours.

RESULTS

The expert group had higher kappa values in evaluating all tumour sizes via CEUS compared with MRI. The novice group had similar kappa values. In patients with tumours measuring ≤3 cm, the expert group had higher kappa values in reading CEUS compared with MRI images; however, in the novice group, the kappa value was lower in evaluating CEUS compared with MRI images. In patients with tumours measuring >3 cm, the expert and novice groups had good to excellent kappa values. The confidence level of the two groups in reading MRI images was high; however, the novice group had a lower confidence level.

CONCLUSION

CEUS is a convenient, cost-effective, and easy to apply imaging tool that can help interventionists perform early detection of viable hepatocellular carcinoma post-TACE. It has a higher inter-rater agreement in interpreting CEUS images compared with MRI images among expert radiologists even when they are extremely familiar with post-cTACE MRI images. In novice radiologists, there may be a learning curve to achieve good consistency in CEUS interpretation.

Modeling Dynamic Recrystallization Behavior in a Novel HIPed P/M Superalloy during High-Temperature Deformation

The dynamic recrystallization (DRX) features and the evolution of the microstructure of a new hot isostatic pressed (HIPed) powder metallurgy (P/M) superalloy are investigated by hot-compression tests. The sensitivity of grain dimension and DRX behavior to deformation parameters is analyzed. The results reveal that the DRX features and grain-growth behavior are significantly affected by deformation conditions. The DRX process is promoted with a raised temperature/true strain or a reduced strain rate. However, the grains grow up rapidly at relatively high temperatures. At strain rates of o.1 s⁻¹ and 1 s⁻¹, a uniform microstructure and small grains are obtained. Due to the obvious differences in the DRX rate at various temperatures, the piecewise DRX kinetics equations are proposed to predict the DRX behavior. At the same time, a mathematical model for predicting the grain dimension and the grain growth behavior is established. To further analyze the DRX behavior and the changes in grain dimension, the hot deformation process is simulated. The developed grain-growth equation as well as the piecewise DRX kinetics equations are integrated into DEFORM software. The simulated DRX features are consistent with the test results, indicating that the proposed DRX kinetics equations and the established grain-growth model can be well used for describing the microstructure evolution. So, they are very useful for the practical hot forming of P/M superalloy parts.

Evolution of Annealing Twins in a Hot Deformed Nickel-Based Superalloy

The hot deformation characteristics of a GH4169 superalloy are investigated at the temperature and strain rate ranges of 1193–1313 K and 0.01–1 s⁻¹, respectively, through Gleeble-3500 simulator. The hot deformed microstructures are analyzed by optical microscopy (OM), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD) technology. The effects of deformation parameters on the features of flow curves and annealing twins are discussed in detail. It is found that the shapes of flow curves are greatly affected by the deformation temperature. Broad peaks appear at low deformation temperatures or high strain rates. In addition, the evolution of annealing twins is significantly sensitive to the deformation degree, temperature, and strain rate. The fraction of annealing twins first decreases and then rises with the added deformation degree. This is because the initial annealing twin characters disappear at the relatively small strains, while the annealing twins rapidly generate with the growth of dynamic recrystallized grains during the subsequent hot deformation. The fraction of annealing twins is relatively high when the deformation temperature is high or the strain rate is low. In addition, the important role of annealing twins on dynamic recrystallization (DRX) behaviors are elucidated. The obvious bulging at initial twin boundaries, and the coherency of annealing twin boundaries with dynamic recrystallized grain boundaries, indicates that annealing twins can motivate the DRX nucleation during the hot deformation.

Microstructure Evolution and a Unified Constitutive Model of Ti-55511 Alloy Compressed at Stepped Strain Rates

The flow behavior and microstructure change of the Ti-55511 alloy are investigated by thermal compression experiments with stepped strain rates. The phase transformation features, the dynamic recrystallization (DRX) behavior of the β matrix, the dynamic spheroidization mechanism of the lamellar α phase and the evolution of the β sub-grain size are quantitatively analyzed. A unified constitutive model is constructed to characterize the hot deformation features of the Ti-55511 alloy. In the established model, the work hardening effect is taken into account by involving the coupled effects of the equiaxed and lamellar α phases, as well as β substructures. The dynamic softening mechanisms including the dynamic recovery (DRV), DRX and dynamic spheroidization mechanisms are also considered. The material parameters are optimized by the multi-objective algorithm in the MATLAB toolbox. The consistency between the predicted and experimental data indicates that the developed unified model can accurately describe the flow features and microstructure evolution of the hot compressed Ti-55511 at stepped strain rates.

Tunable light absorption of graphene using topological interface states

A tunable light absorption of graphene using topological interface states (TISs) is presented. The monolayer graphene is embedded in the interface of asymmetric topological photonic crystals (ATPCs). A strong absorption phenomenon occurs by the excitation of TISs. It is found that the absorption spectra are intensively dependent on the chemical potential of graphene and the periodic number of the ATPCs. Furthermore, the absorption can be rapidly switched in a slight variation of chemical potential, which is modulated by the applied gate voltage on graphene. This study not only opens up a new approach for enhancing light-monolayer graphene interactions, but also provides for practical applications in high absorption optoelectronic devices. This strong absorption phenomenon is different from those in Fabry-Perot resonators, nano-cavities photonic crystal, and traditional topological photonic crystals (TPCs).

Media Freedom is the Primary Culprit for Depressive Disorders: A Cross-National Analysis

Background

There has been much speculation about social environments causing an epidemic of depression. The objectives of this study are to examine how media freedom influences prevalence of depressive disorders. A direct effect of free media is great levels of information complexity causing poor mental health. Two indirect effects are that media freedom facilitates modernization, which is associated with competition-related stress, and government investment in social protection, which impedes the person’s ability to manage stress.

Methods

The study used a cross-sectional analysis on determinants of prevalence of depressive disorders in 2015 covering 98 democratic countries. Media freedom was measured as the degree to which a country allows the freedom of news and information of print media, television, and radio broadcasting (0-100: least to most free). Control variables were then added, including GDP per capita growth, population density, country latitude, and religious affiliations. Further, a mediation analysis was applied to test if there is a causal pathway that links the degrees of media freedom and the levels of economic development or/and social protection to prevalence of depression.

Results

We found that an increase in the score of media freedom by 10 resulted in a 0.20 percentage point increase in prevalence of depressive disorders (%) (0.20, CI = 0.10-0.30). Our theoretical expectations were still confirmed when this study examined the relationship for each year between 2011 and 2014 (e.g. in 2014, 0.19, CI = 0.09-0.29), used an alternative index of media freedom from a practitioners’ view (0.17, CI = 0.02-0.32), or measured each country’s level of internet and digital media freedom (0.30, CI = 0.10-0.49). Further, a mediation test showed that 39.88% and 21.38% of the total effect was mediated through the economic and social pathway respectively.

Conclusions

The findings suggest that great levels of media freedom matter in increasing prevalence of depression.

Key messages

Great levels of media freedom matter in increasing prevalence of depression. There are direct and two indirect effects of media freedom on prevalence of depression.

P1880Entropy-based algorithm for atrial fibrillation detection using photoplethysomgraphic signal recorded by a smart watch

Background

Atrial fibrillation (AF) is the most common arrhythmia, and its paroxysmal and short duration nature makes its detection challenging. The most important limitation of current smartwatches is that patients need to touch to the sensor of the watch to record signals when patients feel discomfort. We developed a wearable smart watch and evaluated its accuracy to differentiate AF from sinus rhythm, which can continuously detecting heart rhythm without hand touching the device.

Methods and results

A wearable smart watch with PPG sensor and electrocardiogram (ECG) recording function was used for signal acquisition. A total 399 patients with a mean age of 67 years old were enrolled in the study, of whom 237 (81.5%) were male, and 101 have been diagnosed with AF. Pulse wave extracted from the green light spectrum of the signal and ECG were recorded for about 10 minutes for each patient. Pulse-to-pulse intervals (PPI) were automatically identified. All ECG signals were verified by two cardiologists. The correlation between R-to-R interval on ECG and PPI were excellent, with a correlation coefficient R >0.99 (p<0.05). An entropy-based algorithm which combined Shannon entropy of successive difference of PPI and sample entropy of PPI was used to discriminate between AF and sinus rhythm. This method had high sensitivity and specificity (96% and 98%, respectively), the area under receiver operating characteristic curve reached 0.98.

Conclusions

We developed an entropy-based algorithm for AF detection with PPG signal recorded by a wearable smart watch. This algorithm discriminates AF from sinus rhythm accurately. This advance in technology overcomes an important clinical obstacle and can increase the AF detection rate tremendously.

[Clinical analysis of five cases of autism spectrum disorder complicated with epilepsy with chromosome copy number variation]

Objective: To explore the clinical features and genetic causes of autism spectrum disorder (ASD) patients with epilepsy. Methods: The clinical data of five patients with ASD and epilepsy admitted to Xuanwu Hospital between September 2017 and September 2018 were collected, including medical history, intelligence level, developmental level, physical examination, neuroimaging and electroencephalogram. High-throughput whole-genome sequencing was applied to five patients and their parents. Results: Of five patients, four were male and one was female. All five patients had mild mental retardation, and one patient had significant growth retardation and craniofacial deformity. The average epilepsy onset age was 6.3 years old (7 months to 16 years). The main epileptic type was tonic-clonic seizure with abnormal EEG results. All patients have a favorable response to anti-epileptic drugs. Whole-exome sequencing (WES) revealed copy number variation in all 5 patients. Among them, 3 cases were reported to be pathogenic, and 2 cases were not reported (chromosome 16p13.3 duplication and chromosome 21q22.3 deletion). Conclusions: The results of current study support that autism spectrum disorders with seizures is often associated with copy number variations, such as Williams-Beuren region duplication syndrome, chromosome 15q11.2 duplication syndrome and chromosome 15q11.2 deletion syndrome. We reported two novel copy number variations (chromosome 16p13.3 duplication and chromosome 21q22.3 deletion) in two autism spectrum disorder patients with epileptic seizures.

Synchronous renal cell carcinoma and pheochromocytoma presenting as acute decompensated heart failure

We report a 49-year-old woman who presented with a hypertensive crisis and acute heart failure and reduced left ventricular systolic function. An abdominal ultrasonography revealed a huge lobulated heterogeneous mass at the lower pole of the right kidney and a mass over the left suprarenal area, which were further delineated by magnetic resonance imaging. The patient underwent laparoscopic right radical nephrectomy and left adrenalectomy. Histopathological analysis confirmed the diagnoses of clear cell renal cell carcinoma of the right kidney with metastasis to the lung; and atypical pheochromocytoma of the left adrenal gland. Target therapy was initiated, which resulted in stabilization of the patient's tumors and the recovery of her heart function. To avoid a delayed diagnosis and catastrophic outcome, clinicians should consider such rare causes of acute decompensated heart failure.

[Clinical features and gene analysis of TBC1D24 gene mutation related early-onset focal myoclonic epilepsy]

Objective: To investigate the clinical features and genetic characteristics of patients with TBC1D24 gene mutation related early-onset focal myoclonic epilepsy. Methods: Clinical data of 3 patients with TBC1D24 gene mutation related early-onset focal myoclonic epilepsy of Xuanwu Hospital from November 2016 to June 2017 was collected and analyzed.Candidate gene mutations were screened by second generation sequencing. Results: Among the 3 patients, 1 was male and 2 were females.Seizure onset age was 4 months, 3 years and 5 years after birth respectively. Two patients had family history of epilepsy.They all had prolonged episodes of focal myoclonus. Two patients had mental retardation.Scalp electroencephalograms (EEG) was recorded in all 3 cases and myoclonic seizures were captured.The ictal EEGs were normal in all cases. In one patient, the ictal EEG of generalized seizure showed alpha rhythm originating from left fronto-central region. Brain magnetic resonance imaging (MRI) was normal in 2 patients. Abnormal signal was found bilaterally in cerebellum in 1 patient. The gene screening showed that two patients carried compound heterozygous mutation of TBC1D24 gene and one carried homozygous mutation, all of which were de novo mutations.All the patients were treated with multiple antiepileptic drugs (AEDs) and seizures were uncontrolled in 2 patients. One patient was followed up for 10 months without recurrence. Conclusions: TBC1D24 gene related early-onset focal myoclonic epilepsy is clinically characterized by early onset, prolonged focal myoclonus which relieved with sleep, mental retardation and poor response to AEDs.The interictal and ictal EEG usually show normal. Genetic analysis can assist in diagnosis and genetic counseling.

Ultra-slow light in one-dimensional Cantor photonic crystals

Ultra-slow light and complete transmission properties in one-dimensional Cantor photonic crystals are presented. In contrast to traditional dielectric photonic crystals, the proposed structure has large group delay, slower group velocity, and a high quality factor within the same layers and materials. This study shows that larger than 1 μs group delay and slower than 1 m/s group velocity are achieved in the fifth-order Cantor photonic crystal with 52.75 μm length. This ultra-slow-light structure is very promising for application in advanced slow-light devices. A high quality factor of 10⁹ and multiband filters with complete transmission can also be obtained by using this approach.

Time-resolved inline digital holography for the study of noncollinear degenerate phase modulation

Recent works demonstrated that digital time-resolved holography is the prospective approach to study nonlinear light-matter interaction processes. In this Letter, we present a straightforward inline holographic approach for studying degenerate phase modulation induced by an inclined collimated pump beam in the isotropic sample. The method is based on a minimization of the difference between experimentally acquired data and simulated inline holograms obtained from a numerical model of pump-probe interaction in optical nonlinear media. A sophisticated experimental data processing algorithm is implemented to provide high sensitivity and a signal-to-noise ratio eligible for soft interaction with a collimated pump beam. The integral phase shift determined by our method can be used to estimate the nonlinear refractive index and the relaxation time for material with a low damage threshold. We validated our approach for the case of soda-lime and BK7 glasses.

Optimization of dietary zinc for egg production and antioxidant capacity in Chinese egg-laying ducks fed a diet based on corn-wheat bran and soybean meal

The aim of this study was to evaluate the effect of zinc supplementation on productive performance and antioxidant status in laying ducks. Five-hundred-four laying ducks were divided into 7 treatments, each containing 6 replicates of 12 ducks. The ducks were caged individually and fed a corn-soybean meal and wheat bran basal diet (37 mg Zn/kg) or the basal diet supplemented with 15, 30, 45, 60, 75, or 90 mg Zn/kg (as zinc sulfate). During the early laying period of 10 d (daily egg production <80%), egg production, daily egg mass, and FCR increased quadratically with increasing dietary Zn levels (P < 0.05). The highest egg production and daily egg weight were obtained when 30 or 45 mg Zn/kg diet was supplemented, with lowest FCR. Similarly, the highest egg production and daily egg mass were observed in the group supplemented with 30 or 45 mg Zn/kg during the peak laying period of the subsequent 120 d (daily egg production >80%). Average egg weight and feed intake did not differ among the groups of graded Zn supplementation.The egg quality was not affected by dietary Zn, including the egg shape index, Haugh unit, yolk color score, egg composition, and shell thickness. The activities of plasma activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) increased in a quadratic manner (P < 0.001) with increasing supplemental Zn. Plasma concentration of Zn increased quadratically (P < 0.05) as dietary Zn increased. The hepatic activity of Cu/Zn-SOD and GSH-PX increased quadratically (P < 0.05) with increasing dietary Zn. Plasma Zn concentrations were positively correlated with activities of T-SOD (P < 0.05), and positively with plasma Cu. Plasma concentration of reduced glutathione was correlated with plasma Cu. In conclusion, supplementation of Zn at 30 or 45 mg/kg to a corn-wheat bran and soybean basal diet may improve the productive performance and enhance the antioxidant capacity.

First-line icotinib versus cisplatin/pemetrexed plus pemetrexed maintenance therapy for patients with advanced EGFR mutation-positive lung adenocarcinoma (CONVINCE): a phase 3, open-label, randomized study

BACKGROUND

Icotinib has been previously shown to be non-inferior to gefitinib in non-selected advanced non-small-cell lung cancer patients when given as second- or further-line treatment. In this open-label, randomized, phase 3 CONVINCE trial, we assessed the efficacy and safety of first-line icotinib versus cisplatin/pemetrexed plus pemetrexed maintenance in lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutation.

PATIENTS AND METHODS

Eligible participants were adults with stage IIIB/IV lung adenocarcinoma and exon 19/21 EGFR mutations. Participants were randomly allocated (1 : 1) to receive oral icotinib or 3-week cycle of cisplatin plus pemetrexed for up to four cycles; non-progressive patients after four cycles were maintained with pemetrexed until disease progression or intolerable toxicity. The primary end point was progression-free survival (PFS) assessed by independent response evaluation committee. Other end points included overall survival (OS) and safety.

RESULTS

Between January 2013 and August 2014, 296 patients were randomized, and 285 patients were treated (148 to icotinib, 137 to chemotherapy). Independent response evaluation committee-assessed PFS was significantly longer in the icotinib group (11.2 versus 7.9 months; hazard ratio, 0.61, 95% confidence interval 0.43-0.87; P = 0.006). No significant difference for OS was observed between treatments in the overall population or in EGFR-mutated subgroups (exon 19 Del/21 L858R). The most common grade 3 or 4 adverse events (AEs) in the icotinib group were rash (14.8%) and diarrhea (7.4%), compared with nausea (45.9%), vomiting (29.2%), and neutropenia (10.9%) in the chemotherapy group. AEs (79.1% versus 94.2%; P < 0.001) and treatment-related AEs (54.1% versus 90.5%; P < 0.001) were significantly fewer in the icotinib group than in the chemotherapy group.

CONCLUSIONS

First-line icotinib significantly improves PFS of advanced lung adenocarcinoma patients with EGFR mutation with a tolerable and manageable safety profile. Icotinib should be considered as a first-line treatment for this patient population.

Effect of culture conditions on metabolites produced by the crinoid-derived fungus Aspergillus ruber 1017

Two different culture media were used to cultivate fungus Aspergillus ruber 1017 and resulted in the isolation of one new compound (1) and 23 known compounds (2-24). Alkaloids were the major metabolite in soybean medium instead of anthraquinone from rice medium. The structures of these compounds were elucidated according to spectroscopic analysis and comparison with reported data. Antibacterial activities of compounds 1-12 against 12 aquatic bacteria were evaluated.

Acidification and sulfide formation control during reductive dechlorination of 1,2-dichloroethane in groundwater: Effectiveness and mechanistic study

To enhance the reductive dechlorination of 1,2-dichloroethane (DCA) in groundwater, substrate injection may be required. However, substrate biodegradation causes groundwater acidification and sulfide production, which inhibits the bacteria responsible for DCA dechlorination and results in an odor problem. In the microcosm study, the effectiveness of the addition of ferrous sulfate (FS), desulfurization slag (DS), and nanoscale zero-valent iron (nZVI) on acidification and sulfide control was studied during reductive dechlorination of DCA, and the emulsified substrate (ES) was used as the substrate. Up to 94% of the sulfide was removed with FS and DS addition (0.25 wt%) (initial DCA concentration = 13.5 mg/L). FS and DS amendments resulted in the formation of a metal sulfide, which reduced the hydrogen sulfide concentration as well as the subsequent odor problem. Approximately 96% of the DCA was degraded under reductive dechlorination with nZVI or DS addition using ES as the substrate. In microcosms with nZVI or DS addition, the sulfide concentration was reduced to less than 15 μg/L. Acidification can be controlled via hydroxide ions production after nZVI oxidation and reaction of free CaO (released from DS) with water, which enhanced DCA dechlorination. The quantitative polymerase chain reaction results confirmed that the microcosms with nZVI added had the highest Dehalococcoides population (up to 2.5 × 10(8) gene copies/g soil) due to effective acidification control. The α-elimination mechanism was the main abiotic process, and reductive dechlorination dominated by Dehalococcides was the biotic mechanism that resulted in DCA removal. More than 22 bacterial species were detected, and dechlorinating bacteria existed in soils under alkaline and acidic conditions.

Single-agent capecitabine as maintenance therapy after induction of XELOX (or FOLFOX) in first-line treatment of metastatic colorectal cancer: randomized clinical trial of efficacy and safety

BACKGROUND

The optimal strategy of maintenance therapy for patients with mCRC is controversial. This study was to evaluate the efficacy and safety of maintenance therapy with capecitabine versus observation following inductive chemotherapy in patients with metastatic colorectal cancer.

PATIENTS AND METHODS

In this randomized, open-label, multicenter, phase III trial, patients who received 18-24 weeks of induction chemotherapy with XELOX or FOLFOX and achieved disease control were randomly assigned centrally (1:1) to receive maintenance therapy of capecitabine or only observation until disease progression. The primary end point was progression-free survival (PFS) from randomization; the secondary end points included overall survival (OS), PFS from induction treatment (PFS2) and safety. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT02027363.

RESULTS

Between 30 July 2010 and 15 September 2013, 274 patients were enrolled in the study from 11 sites in China and randomly assigned to maintenance group (n = 136) or observation group (n = 138). Clinicopathological characteristics were balanced in two groups. The median follow-up time from randomization was 29.0 months [interquartile range (IQR) 21-36 months]. The primary end point of PFS was statistically significantly longer in capecitabine maintenance group than in observation group {6.43 [95% confidence interval (CI) 5.26-7.71] versus 3.43 (2.83-4.16) months, HR 0.54 (0.42-0.70), P < 0.001}. The median OS of capecitabine maintenance group was longer than that of observation group, but not statistically significant [25.63 (22.46-27.80) versus 23.30 (19.68-26.92) months; HR 0.85 (0.64-1.11), P = 0.2247]. Similar safety profiles were observed in both arms. The most common grade 3 or 4 toxicities in capecitabine maintenance group versus observation group were neutropenia, hand-foot syndrome, and mucositis.

CONCLUSIONS

Maintenance therapy with a single agent of capecitabine can be considered an appropriate option following the induction of XELOX or FOLFOX in mCRC patients with acceptable toxicities.

CLINICAL TRIALS NUMBER

NCT02027363.

Upregulation of Haploinsufficient Gene Expression in the Brain by Targeting a Long Non-coding RNA Improves Seizure Phenotype in a Model of Dravet Syndrome

Dravet syndrome is a devastating genetic brain disorder caused by heterozygous loss-of-function mutation in the voltage-gated sodium channel gene SCN1A. There are currently no treatments, but the upregulation of SCN1A healthy allele represents an appealing therapeutic strategy. In this study we identified a novel, evolutionary conserved mechanism controlling the expression of SCN1A that is mediated by an antisense non-coding RNA (SCN1ANAT). Using oligonucleotide-based compounds (AntagoNATs) targeting SCN1ANAT we were able to induce specific upregulation of SCN1A both in vitro and in vivo, in the brain of Dravet knock-in mouse model and a non-human primate. AntagoNAT-mediated upregulation of Scn1a in postnatal Dravet mice led to significant improvements in seizure phenotype and excitability of hippocampal interneurons. These results further elucidate the pathophysiology of Dravet syndrome and outline a possible new approach for the treatment of this and other genetic disorders with similar etiology.

In-situ atomic layer deposition of tri-methylaluminum and water on pristine single-crystal (In)GaAs surfaces: electronic and electric structures

The electronic structure of single-crystal (In)GaAs deposited with tri-methylaluminum (TMA) and water via atomic layer deposition (ALD) is presented with high-resolution synchrotron radiation core-level photoemission and capacitance-voltage (CV) characteristics. The interaction of the precursor atoms with (In)GaAs is confined at the topmost surface layer. The Ga-vacant site on the GaAs(111)A-2 × 2 surface is filled with Al, thereby effectively passivating the As dangling bonds. The As-As dimers on the GaAs(001)-2 × 4 surface are entirely passivated by one cycle of TMA and water. The presumed layerwise deposition fails to happen in GaAs(001)-4 × 6. In In0.20Ga0.80As(001)-2 × 4, the edge row As atoms are partially bonded with the Al, and one released methyl then bonds with the In. It is suggested that the unpassivated surface and subsurface atoms cause large frequency dispersions in CV characteristics under the gate bias. We also found that the (In)GaAs surface is immune to water in ALD. However, the momentary exposure of it to air (less than one minute) introduces significant signals of native oxides. This indicates the necessity of in situ works of high κ/(In)GaAs-related experiments in order to know the precise interfacial atomic bonding and thus know the electronic characteristics. The electric CV measurements of the ALD-Al2O3 on these (In)GaAs surfaces are correlated with their electronic properties.

Xyloketal B attenuates atherosclerotic plaque formation and endothelial dysfunction in apolipoprotein e deficient mice

Our previous studies demonstrated that xyloketal B, a novel marine compound with a unique chemical structure, has strong antioxidant actions and can protect against endothelial injury in different cell types cultured in vitro and model organisms in vivo. The oxidative endothelial dysfunction and decrease in nitric oxide (NO) bioavailability are critical for the development of atherosclerotic lesion. We thus examined whether xyloketal B had an influence on the atherosclerotic plaque area in apolipoprotein E-deficient (apoE-/-) mice fed a high-fat diet and investigated the underlying mechanisms. We found in our present study that the administration of xyloketal B dose-dependently decreased the atherosclerotic plaque area both in the aortic sinus and throughout the aorta in apoE-/- mice fed a high-fat diet. In addition, xyloketal B markedly reduced the levels of vascular oxidative stress, as well as improving the impaired endothelium integrity and NO-dependent aortic vasorelaxation in atherosclerotic mice. Moreover, xyloketal B significantly changed the phosphorylation levels of endothelial nitric oxide synthase (eNOS) and Akt without altering the expression of total eNOS and Akt in cultured human umbilical vein endothelial cells (HUVECs). Here, it increased eNOS phosphorylation at the positive regulatory site of Ser-1177, while inhibiting phosphorylation at the negative regulatory site of Thr-495. Taken together, these findings indicate that xyloketal B has dramatic anti-atherosclerotic effects in vivo, which is partly due to its antioxidant features and/or improvement of endothelial function.