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InGaN-based long-wavelength light-emitting diodes (LEDs) are indispensable components for the next-generation solid-state lighting industry. In this work, we introduce additional InGaN/GaN pre-wells in LED structure and investigate the influence on optoelectronic properties of yellow (~575 nm) LEDs. It is found that yellow LED with pre-wells exhibits a smaller blue shift, and a 2.2-fold increase in light output power and stronger photoluminescence (PL) intensity compared to yellow LED without pre-wells. The underlying mechanism is revealed by using Raman spectra, temperature-dependent PL, and X-ray diffraction. Benefiting from the pre-well structure, in-plane compressive stress is reduced, which effectively suppresses the quantum confined stark effect. Furthermore, the increased quantum efficiency is also related to deeper localized states with reduced non-radiative centers forming in multiple quantum wells grown on pre-wells. Our work demonstrates a comprehensive understanding of a pre-well structure for obtaining efficient LEDs towards long wavelengths.

Background Transcutaneous electrical acupoint stimulation (TEAS), which is also known as acupuncture-like transcutaneous electrical nerve stimulation (TENS), has been widely used in acute or chronic pain. However, previous research has not demonstrated that TEAS is effective for cancer-related pain. Opioid drugs are strongly recommended for treating cancer-related pain, but opioid-induced immunosuppression is still the most intractable drug-induced medical problem. Evaluating the efficacy and potential advantage of TEAS combined with opioid drugs in moderate and severe cancer-related pain in China is important because such studies are lacking. Methods/Design This trial is a multicenter, prospective randomized controlled clinical trial. In total, 160 patients who were enrolled from two hospitals in the Zhejiang Province (China) will be randomly allocated into two groups: a TEAS group and sham TEAS group without acupoint electrical stimulation. Both groups will receive a 21-day interval of chemotherapy and conventional cancer pain therapy. Fifteen treatment sessions will be performed over a three-week period. The primary outcomes will be measured by changes in the Numerical Rating Scale (NRS) scores and equivalent dosage of morphine at baseline, three weeks of treatment and one two-week follow-up. The secondary outcome measures include cellular immunity function, life quality assessment, opioids side effects assessment, and safety and compliance evaluation. Discussion This trial is expected to clarify whether TEAS is effective for cancer-related pain. These results demonstrate the advantage of TEAS combined with opioid drugs on improving immune function and decreasing opioid induced side effects. Trial registration Chinese Clinical Trial Registry, ChiCTR-13003803. Registered on 27 August 2013. Electronic supplementary material The online version of this article (10.1186/s13063-018-3145-y) contains supplementary material, which is available to authorized users.

The current outbreak of coronavirus disease 2019 (COVID-19) has been defined as a pandemic by the World Health Organization. We aimed to evaluate the clinical features and virological course of non-severe COVID-19 patients with or without symptoms who were admitted to a Chinese cabin hospital. In this retrospective single center study, we reviewed 252 laboratory-confirmed COVID-19 patients treated at one temporary cabin hospital in Wuhan, China. Demographic, clinical, serial chest computed tomography (CT), and serial viral test data were compared between asymptomatic and symptomatic patients. The association between clinical features and symptomatic status or patient referral status was analyzed. Among all 252 patients, 74 (29.4%) were asymptomatic and 138 (54.76%) had more than two family members who developed COVID-19. The probability for family clustering was similar between asymptomatic and symptomatic patients (59.70 vs. 61.64%, P = 0.79). Asymptomatic patients and symptomatic patients were equally likely to reach a virus-free state during their stay at the cabin hospital (93.15 vs. 86.44%, P = 0.13). The initial chest CT screening showed that 81 (32.1%) patients had no visible pneumonia, 52 (20.6%) had unilateral pneumonia, and 119 (47.2%) had bilateral pneumonia. Symptomatic patients had a higher chance to have bilateral pneumonia (P < 0.0001) and were less likely to show improvement on the follow-up CT scan (P = 0.0002). In total, 69 (27.4%) patients were referred to the designated hospital and only 23 (9.1%) patients were referred due to the progression of pneumonia. Non-severe COVID-19 patients can transmit the disease regardless of their symptomatic status. It is highly recommended that asymptomatic patients be identified and quarantined to eliminate the transmission of COVID-19.

Background: 2019 novel coronavirus disease (COVID-19) has been characterized as a pandemic by WHO Clinical and virological course of patients with severe disea

The realization of efficient III-nitride emitters in the green-to-amber region is fundamental to the monolithic integration of multicolor emitters and the development of III-nitride-based full-color high-resolution displays. A hybrid nucleation layer, which includes sputtered AlN and mid-temperature GaN components, was proposed for the development of efficient III-nitride emitters in the green-to-amber region. The mid-temperature GaN component in the hybrid nucleation layer induced the formation of a stacking fault band structure, which effectively relaxed the misfit stress at the GaN/sapphire interface. A reduced dislocation density and in-plane compressive stress in InGaN/GaN multiple quantum wells were obtained on the hybrid nucleation layer in comparison with the conventional sputtered AlN nucleation layer. Consequently, a significantly enhanced internal quantum efficiency and improved light output power were achieved for the LEDs grown on the hybrid nucleation layer. This gain is attributed to the increased localization depth and spatial overlapping of the electron and hole wave functions. In the present study, the hybrid nucleation layer provides a promising approach for the pursuit of efficient III-nitride emitters in the green-to-amber region.

High-quality and crack-free aluminum nitride (AlN) film on sapphire substrate is the foundation for high-efficiency aluminum gallium nitride (AlGaN)-based deep ultraviolet light-emitting diodes (DUV LEDs). We reported the growth of high-quality and crack-free AlN film on sapphire substrate with a nanometer-scale-thick AlN nucleation layer (NL). Three kinds of nanometer-scale-thick AlN NLs, including in situ low-temperature AlN (LT-AlN) NL, oxygen-undoped ex situ sputtered AlN NL, and oxygen-doped ex situ sputtered AlN NL, were prepared for epitaxial growth of AlN films on sapphire substrates. The influence of nanoscale AlN NL thickness on the optical transmittance, strain state, surface morphology, and threading dislocation (TD) density of the grown AlN film on sapphire substrate were carefully investigated. The average optical transmittance of AlN film on sapphire substrate with oxygen-doped sputtered AlN NL was higher than that of AlN films on sapphire substrates with LT-AlN NL and oxygen-undoped sputtered AlN NL in the 200&ndash, 270 nm wavelength region. However, the AlN film on sapphire substrate with oxygen-undoped sputtered AlN NL had the lowest TD density among AlN films on sapphire substrates. The AlN film on sapphire substrate with the optimum thickness of sputtered AlN NL showed weak tensile stress, a crack-free surface, and low TD density. Furthermore, a 270-nm AlGaN-based DUV LED was grown on the high-quality and crack-free AlN film. We believe that our results offer a promising and practical route for obtaining high-quality and crack-free AlN film for DUV LED.

Metastasis is the dominant cause of patient death in small-cell lung cancer (SCLC), and a better understanding of the molecular mechanisms underlying SCLC metastasis may potentially improve clinical treatment. Through genome-scale screening for key regulators of mouse Rb1(–/–) Trp53(–/–) SCLC metastasis using the pooled CRISPR/Cas9 library, we identified Cullin5 (CUL5) and suppressor of cytokine signaling 3 (SOCS3), two components of the Cullin-RING E3 ubiquitin ligase complex, as top candidates. Mechanistically, the deficiency of CUL5 or SOCS3 disrupted the functional formation of the E3 ligase complex and prevented the degradation of integrin β1, which stabilized integrin β1 and activated downstream focal adhesion kinase/SRC (FAK/SRC) signaling and eventually drove SCLC metastasis. Low expression levels of CUL5 and SOCS3 were significantly associated with high integrin β1 levels and poor prognosis in a large cohort of 128 clinical patients with SCLC. Moreover, the CUL5-deficient SCLCs were vulnerable to the treatment of the FDA-approved SRC inhibitor dasatinib. Collectively, this work identifies the essential role of CUL5- and SOCS3-mediated integrin β1 turnover in controlling SCLC metastasis, which might have therapeutic implications.

We report the metal-organic chemical vapor deposition growth of high-quality AlN on sapphire enabled by an alternating V/III ratio AlN superlattice. We demonstrated that the insertion of an alternating V/III ratio AlN superlattice facilitates the relaxation of tensile stress during growth and assists the annihilation of threading dislocations. Dislocation inclination was proposed to play a major role in the stress relaxation and dislocation reduction, which not only provides an effective misfit-dislocation component but also increases the dislocation reaction probability. By this method, crack-free 3.25 μm-thick AlN films were grown on flat sapphire substrate (FSS) and nano-patterned sapphire substrate (NPSS) at 1180 °C, and the full width at half maximum of (002)/(102) rocking curves was 204/408 and 152/323 arcsec for such AlN/FSS and AlN/NPSS templates.

High-efficiency InGaN-based yellow light-emitting diodes (LEDs) with high brightness are desirable for future high-resolution displays and lighting products. Here, we demonstrate efficient InGaN-based yellow (∼570 nm) LEDs with optimized three-layer staggered quantum wells (QWs) that are grown on patterned sapphire substrates. Numerical simulations show that the electron–hole wavefunction overlap of staggered InGaN QWs with high In content exhibits a 1.7-fold improvement over that of square InGaN QWs. At the same injection current, LEDs with staggered QWs exhibit lower forward voltages and narrower full widths at half maximum than LEDs with square QWs. The light output power and external quantum efficiency of a staggered QW LED are 10.2 mW and 30.8%, respectively, at 15 mA. We combine atomic probe tomography (APT), time-resolved photoluminescence (TRPL), and transmission electron microscopy (TEM) with energy-dispersive x-ray (EDX) mapping spectroscopy to shed light on the origin of enhanced device performance. APT results confirm the staggered In profile of our designed staggered QWs structure, and TRPL results reveal decreased defect-state carrier trapping in staggered QWs. Furthermore, TEM with EDX mapping spectroscopy supports the viewpoint that staggered QWs exhibit uniform elemental distribution and improved crystal quality. Together, these factors above contribute to enhanced LED performance. Our study shows that staggered InGaN QWs provide a promising strategy for the development of LEDs that are efficient in the long-wavelength region.

Objective To compare the complication rates after uterine artery chemoembolization (UACE) followed by dilation and curettage (D&C) guided by different types of monitoring for treatment of cesarean scar pregnancy (CSP). Methods A randomized controlled trial was undertaken of women with CSP attending a hospital in Wuhan, China, between June 1, 2010, and June 30, 2014. Using sealed opaque envelopes containing random numbers, participants were randomly allocated to undergo D&C with hysteroscopy monitoring, ultrasonography monitoring, or no monitoring. Participants and investigators were masked to group assignment. The primary outcome was the number of participants with complications at 2 months of follow-up after D&C. Analyses were by intention to treat. Results Among 144 participants, 48 were assigned to hysteroscopy monitoring, 44 to ultrasonography monitoring, and 52 to no monitoring. Complications were noted for 1 (2.1%) patient in the hysteroscopy group, 2 (4.5%) in the ultrasonography group, and 12 (23.1%) in the no monitoring group (P = 0.001). Conclusion Hysteroscopy or ultrasonography monitoring of D&C after UACE for CSP treatment can decrease the complication rate. ClinicalTrials.gov: NCT02357095.

We demonstrate the achieving of high-quality AlN films on flat sapphire substrate (FSS) by introducing voids during growth. Voids are embedded into AlN epilayers through a growth-mode transition from island growth to step flow growth. Such voids significantly facilitated the underlying dislocations annihilation as demonstrated by the transmission electron microscopy (TEM) image. For the 3 μm-thick AlN film grown on FSS, the full width at half maximum of the X-ray rocking curve was 57/260 arcsec for (0 0 2)/(1 0 2) reflection and a threading dislocation density of 1.7 × 108 cm−2 was determined from plain-view TEM image. Moreover, the voids provided an additional stress relief channel in the AlN film grown on FSS, resulting in a tensile stress comparable to that of grown on nano-patterned sapphire substrate (NPSS). The measured lattice constants and Raman shift of AlN-E2 (high) peak verified the 3 μm-thick AlN film grown on FSS is nearly stress free at room temperature. Taking advantages of the deliberately embedded voids, a crack-free and atomically flat AlN film was grown on FSS. The strategy put forward in this work to obtaining high-quality AlN films on FSS is much cost-efficient, which is believed to hold great promise for commercialization in AlN-based devices.

Accurate lumbar spine measurement in CT images provides an essential way for quantitative spinal diseases analysis such as spondylolisthesis and scoliosis. In today’s clinical workflow, the measurements are manually performed by radiologists and surgeons, which is time consuming and irreproducible. Therefore, automatic and accurate lumbar spine measurement algorithm becomes highly desirable. In this study, we propose a method to automatically calculate five different lumbar spine measurements in CT images. There are three main stages of the proposed method: First, a learning based spine labeling method, which integrates both the image appearance and spine geometry information, is used to detect lumbar and sacrum vertebrae in CT images. Then, a multiatlases based image segmentation method is used to segment each lumbar vertebra and the sacrum based on the detection result. Finally, measurements are derived from the segmentation result of each vertebra. Our method has been evaluated on 138 spinal CT scans to automatically calculate five widely used clinical spine measurements. Experimental results show that our method can achieve more than 90% success rates across all the measurements. Our method also significantly improves the measurement efficiency compared to manual measurements. Besides benefiting the routine clinical diagnosis of spinal diseases, our method also enables the large scale data analytics for scientific and clinical researches.

Objectives: To investigate the relationship between maximum standardized uptake value (SUVmax) of 18F-FDG PET/CT and clinicopathological features of oral squamous cell carcinoma (OSCC), in order to formulate a better clinical guideline. Methods: In 104 patients with OSCC confirmed by pathology, there were 67 males and 37 females (age, 33–76 years; mean age, 56 years).18FDG, 18-fludeoxyglucose (18F-FDG) PET/CT manifestations and the clinicopathological features of the 104 patients were retrospectively analysed. Single-factor analysis and multiple regression analysis were conducted on possible factors influencing primary tumour SUVmax, including gender, age, smoking history, tumour location, tumour size, histological differentiation, TNM stage, T stage, N stage. Diagnostic performance of SUVmax for invading peri-tissue of OSCC was measured by the area under receiver operating characteristic curve, and sensitivity and specificity were determined at the Youdons index. Results: The single-analysis results showed that SUVmax was correlated with the histological differentiation, tumour size, TNM stage, T stage, N stage(p < 0.05), yet it was not correlated with gender, age, smoking history, tumour location (p > 0.05). Multivariate liner regression analysis showed that tumour size, TNM stage were influencing factors independent of primary tumour SUVmax (p < 0.05). Primary tumour SUVmax had predictive value for invading peri-tissue of OSCC. When the cutoff value was 7.98, the diagnostic efficiency was the highest, with the sensitivity being 90.0％ and the specificity being 76.2%. Conclusions: OSCC 18F-FDG PET/CT SUVmax is higher among patients with larger tumour size, poorer stage, and that primary tumour SUVmax is of important significance in predicting invading peri-tissue.

Aim: Tongue carcinoma is one of the most common oral and maxillofacial malignant tumors worldwide, maximum standardized uptake value (SUVmax) in 18 F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (PET/CT) has been widely used in cancer research; however, there are few systematical reports on the relationship between SUVmax and clinicopathological characteristics in tongue squamous cell carcinoma (TSCC). This study aimed to investigate the relationship between them and whether SUV parameters can predict lymph node metastasis. Materials and Methods: PET/CT manifestations and clinicopathological features of 52 patients with TSCC confirmed by pathology were retrospectively analyzed. Single-factor and multiple regression analyses were conducted on possible factors influencing TSCC SUVmax, including sex, age, smoking history, tumor location and size, histological differentiation, and tumor node metastasis (TNM) stages, T stages, and N stages. Diagnostic performance of SUVmax for lymph node metastasis was measured by the area under the receiver operating characteristic curve, and sensitivity and specificity were determined by Youden's J statistic. Results: SUVmax was correlated with sex, tumor location and size, and TNM stages, T stages, and N stages (P < 0.05) but was not correlated with histological differentiation, smoking history, and age (P > 0.05). Sex, tumor location, tumor size, and N stage were influencing factors independent of TSCC SUVmax (P < 0.05). TSCC SUVmax had predictive value for lymph node metastasis. When the cutoff value was 6.57, the diagnostic efficiency was the highest, with the sensitivity being 79.2% and the specificity being 85.7%. Conclusions: SUVmax was higher among male patients with TSCC with posterior tumor location, larger tumor size, and lymph node metastasis, and TSCC SUVmax was important in predicting lymph node metastasis.

Lumbar spondylolisthesis is one of the most common spinal diseases. It is caused by the anterior shift of a lumbar vertebrae relative to subjacent vertebrae. In current clinical practices, staging of spondylolisthesis is often conducted in a qualitative way. Although meyerding grading opens the door to stage spondylolisthesis in a more quantitative way, it relies on the manual measurement, which is time consuming and irreproducible. Thus, an automatic measurement algorithm becomes desirable for spondylolisthesis diagnosis and staging. However, there are two challenges. 1) Accurate detection of the most anterior and posterior points on the superior and inferior surfaces of each lumbar vertebrae. Due to the small size of the vertebrae, slight errors of detection may lead to significant measurement errors, hence, wrong disease stages. 2) Automatic localize and label each lumbar vertebrae is required to provide the semantic meaning of the measurement. It is difficult since different lumbar vertebraes have high similarity of both shape and image appearance. To resolve these challenges, a new auto measurement framework is proposed with two major contributions: First, a learning based spine labeling method that integrates both the image appearance and spine geometry information is designed to detect lumbar vertebrae. Second, a hierarchical method using both the population information from atlases and domain-specific information in the target image is proposed for most anterior and posterior points positioning. Validated on 258 CT spondylolisthesis patients, our method shows very similar results to manual measurements by radiologists and significantly increases the measurement efficiency.

The present study evaluated the efficacy and safety of maintenance therapy with oral etoposide following first-line docetaxel-cisplatin chemotherapy in patients with metastatic non-small cell lung cancer. The overall response rate in the docetaxel-cisplatin phase was 30.4%, with complete response of 0, partial response of 28, stable disease of 39. Maintenance chemotherapy with oral etoposide was given in 67 patients. No complete response was observed, but 10 patients presented with partial response and 45 with stable disease . The median time to progression was 5.0 months; median overall survival time was 10 months and the 1-year survival rate was 41% during the maintenance therapy. Therapy with oral etoposide was well tolerated with the hematologic toxicities, fatigue and oral mucositis being the most frequent side effects. Docetaxel-cisplatin chemotherapy followed by maintenance therapy with oral etoposide was well tolerated and moderately active against metastatic metastatic non-small cell lung cancer.

Apart from random noise, an atomic force microscopic (AFM) image may also suffer from an inclined plane owing to the in-coincidence between the scanning plane and the sample plane. While the wavelet-shrinkage-based image denoising technique was applied to remove the noise in the AFM image, the least-square-fitting technique was applied to the approximate sub-image so as to emendate the inclined plane. By using this method, the image de-noising and incline emendation can be implemented in parallel. As incline emendation was implemented in the approximate sub-band, the time cost for incline fitting is greatly reduced, and hence the real-time performance of the algorithm is improved. In addition, as the algorithm was implemented by means of wavelet transform, it can be easily combined with the wavelet-based image compression, which is beneficial to in-situ analysis and processing of AFM images. Through experiments, the new method was evaluated by employing an AFM image and the results were given and discussed.