The impact of general anesthesia on the outcomes of preterm infants with gestational age less than 32 weeks delivered via cesarean section.

Background: Recent advancements in China's perinatal and neonatal intensive care have significantly reduced neonatal mortality, yet preterm births before 32 weeks remain the primary cause of neonatal fatalities and contribute to long-term disabilities. The prognosis of very preterm infants (VPIs) is significantly affected by factors including the intrauterine environment, delivery method and neonatal intensive care. Cesarean section which often used for preterm births has implications that are not fully understood, particularly concerning the type of anesthesia used. This study examines the impact of general anesthesia (GA) during cesarean delivery on VPI outcomes, aiming to identify strategies for mitigating GA-associated risks. Methods: This cohort study analyzed 1,029 VPIs born via cesarean section under 32 weeks' gestation at our single-center from 1 January 2018, to 31 December 2022. Detailed medical records, encompassing perioperative information, maternal data and neonatal outcomes were meticulously examined. The primary aim of this investigation was to compare maternal characteristics and neonatal outcomes between VPIs delivered under GA and neuraxial anesthesia (NA). A significance level of p < 0.05 was established. Results: Of the 1,029 VPIs analyzed, 87.95% (n = 905) were delivered via NA and 12.05% (n = 124) via GA. Mothers with hypertensive pregnancy diseases and emergency operations were more inclined to choose GA. VPIs delivered under GA showed a lower Apgar score at one and 5 minutes (p < 0.01), increased need for tracheal intubation resuscitation (32.2% vs. 12.2%, p < 0.01) and a greater incidence of severe neurological injury (SNI) (14.5% vs. 5%, p < 0.01). Multivariable analysis revealed GA was significantly associated with lower Apgar scores at one (OR 6.321, 95% CI 3.729-10.714; p < 0.01) and 5 minutes (OR 4.535, 95% CI 2.975-6.913; p < 0.01), higher risk of tracheal intubation resuscitation (OR = 3.133, 95% CI = 1.939-5.061; p < 0.01) and SNI (OR = 3.019, 95% CI = 1.615-5.643; p < 0.01). Furthermore, for VPIs delivered under GA, a prolonged interval from skin incision to fetus delivery was associated with a lower 5-min Apgar score (p < 0.01). Conclusion: This study revealed the significant impact of GA on adverse outcomes among VPIs. In cases when GA is required, proactive measures should be instituted for the care of VPIs such as expediting the interval from skin incision to fetal delivery.

Cross Relaxation Channel Tailored Temperature Response in Er3+ -rich Upconversion Nanophosphor.

Recently high doping of lanthanide ions (till 100 %) is realized unprecedentedly in nanostructured upconversion (UC) phosphors. However, oddly enough, this significant breakthrough did not result in a corresponding UC enhancement at ambient temperature, which hinders the otherwise very interesting applications of these materials in various fields. In this work, taking the Er3+ -rich UC nanosystem as an example, we confirm unambiguously that the phonon-assisted cross relaxation (CR) is the culprit. More importantly, combining the theoretical modeling and experiments, the precise roles of different CR channels on UC energy loss are quantitatively revealed. As a result, lowering the temperature can exponentially enhance the relevant UC luminescence by more than two orders of magnitude. Our comprehension will play an important role in promoting the UC performance and further application of high doping rare earth materials. As a proof of concept, an Er3+ -rich core/multi-shell nanophosphor is exploited which demonstrates the great potential of our finding in the field of ultra-sensitive temperature sensing.

Application of Blurred Image Processing and IoT Action Recognition in Sports Dance Sports Training.

In order to process the blurred image, this study proposes to combine the blurred point functions in the invariant space into multiple blurred images and then restore them through the deconvolution operation. The PSF functions of the fuzzy invariant space are combined to obtain the fuzzy invariant space. Finally, a gradual restoration method is used to perform many blurred image processing steps. The experimental results prove that the method proposed in this study can avoid the noise introduced in the process of multiple deconvolutions, can reduce the calculation error, and can improve the recovery effect. Based on fuzzy image processing, this research studies the nature of human motion and the identification of actions in the Internet of Things, which provides new ideas and methods for recognition research. The Kinect somatosensory camera of the Internet of Things is used to capture deep images, and 20 three-dimensional points of the human skeleton structure are obtained through its SDK. Based on this, the motion characteristics of human joints were studied, and a motion resolution model suitable for the Internet of Things was proposed. The model has low complexity, simple calculation, and sorting characteristics. Based on this, this research study also uses software engineering ideas and general methods of system development to design and create sports dance management information systems and uses advanced methods such as computers and the Internet to maintain training management to achieve optimal sports training for sports dance mode and to provide information about the management of sports dance athletes training to improve efficiency and the management level.

The Effects of Tai Chi on the Executive Functions and Physical Fitness in Middle-Aged Adults with Depression: A Randomized Controlled Trial.

Objective: The present study examined the effects of Tai Chi exercise on the executive functions (EFs) and physical fitness of middle-aged adults with depression. Methods: A total of 39 middle-aged adults with depression (M age = 50.59, SD = 7.38) were randomly assigned to the Tai Chi group (n = 20) or the waiting-list control group (n = 19). The Tai Chi group engaged in two 90 min sessions of Tai Chi exercise per week for 12 weeks; the waiting-list control group was asked to maintain their usual daily routines for 12 weeks. Depression symptoms, EFs (i.e., inhibitory control, planning, working memory, and cognitive flexibility), and physical fitness (i.e., cardiovascular fitness, muscular strength, muscular endurance, power, and flexibility) were evaluated at the baseline (pretest), 6-week (mid-test), and 12-week (post-test) marks. Results: Both groups showed decreased depression symptoms over time. Compared with the control group, the Tai Chi group showed decreased reaction times for incongruent conditions in the Stroop test from pretest to mid- and post-test, and shorter reaction time for incongruent conditions in the Stroop test than the control group at post-test; the Tai Chi group performed significantly better than the control group in overall total move score of Tower of London (TOL). The Tai Chi group also showed increased total correct scores of TOL from pretest to mid- and post-test, and greater total correct scores of TOL than the control group at post-test. Additionally, results indicated that Tai Chi exercise comprehensively improved physical fitness from pretest to mid- and post-test. Greater performance in terms of cardiovascular fitness, muscular strength, and power was also found in the Tai Chi group at post-test than in the control group. Conclusions: These findings suggest that the 12-week Tai Chi exercise improved inhibitory control, planning and working memory aspects of executive functions, and physical fitness in middle-aged adults with depression.

Effects of Acute High-Intensity Interval Exercise and High-Intensity Continuous Exercise on Inhibitory Function of Overweight and Obese Children.

This study aimed to examine whether a single bout each of high-intensity interval exercise (HIIE) and high-intensity continuous exercise (HICE) could improve inhibitory functions of overweight and obese children, and which mode of exercise was more beneficial. Seventy-two overweight and obese children, with (26.02 ± 1.05 kg/m2), aged 10-14 years (11.56 ± 1.03 years), were randomly assigned to three groups. The HIIE group completed a 30-min treadmill exercise session (5-min warm up, 20-min HIIE, and 5-min cool-down). The HICE group performed 30 min of rope skipping, while the control (CON) group watched a designated cartoon on a tablet computer for the same duration. Reaction time and number of errors in the Stroop test were determined before and after the intervention. The difference between pre- and post-test reaction time scores was higher in the HIIE and HICE groups than in the CON group, while the pre- and post-test difference in the number of errors was similar between groups. Overall, it is likely that both acute HIIE and HICE were similarly efficient in facilitating cognitive and inhibitory functions of children with overweight and obesity conditions, supporting the benefits of acute high-intensity exercise probability for cognitive functions of children in general, as well as of the population with overweight and obesity conditions.

Metaplastic breast carcinoma: a retrospective study of 26 cases.

Metaplastic breast carcinoma is a rare invasive breast cancer. Metaplastic breast carcinoma is mainly characterized by an epithelial or mesenchymal cell population mixed with adenocarcinoma. We collected 26 cases of metaplastic breast carcinoma in the First Affiliated Hospital of Bengbu Medical College from 2008 to 2014. Tumor size, tumor grade, vascular invasion, ER/PR status, histologic classification, and HER2/neu status were assessed for all cases and the literature was reviewed. Clinicopathologic characteristics of patients diagnosed with metaplastic breast carcinomas and its key points of differential diagnosis were discussed. All patients were female, with the median age of 50 years. The mean tumor size was 3.2 cm. 4 subtypes of metaplastic breast carcinomas were documented. Fibromatosis-like metaplastic carcinomas are typically characterized by wavy, intertwined, gentle spindle cells. When the tumor components are almost squamous cell carcinoma components and the primary squamous cell carcinoma of other organs and tissues are excluded, we can diagnose breast squamous cell carcinoma. In spindle cell carcinoma, atypical spindle cells are arranged in many ways and are usually accompanied by inflammatory cell infiltrate. Cancer with interstitial differentiation has mixed malignant epithelial and mesenchymal differentiation, and the mesenchymal components are diverse. Most tumors are triple negative. At present, surgical resection combined with chemotherapy or radiation therapy is the most effective and acceptable method for treating metaplastic breast carcinoma.

MiR-485-3p serves as a biomarker and therapeutic target of Alzheimer's disease via regulating neuronal cell viability and neuroinflammation by targeting AKT3.

BACKGROUND: Numerous microRNAs (miRNAs) have been identified as functional molecules in Alzheimer's disease (AD) pathogenesis. This study aimed to investigate the diagnostic value of microRNA-485-3p (miR-485-3p) in AD patients, evaluate the effect of miR-485-3p on neuronal viability and neuroinflammation, as well as the underlying molecular mechanisms. METHODS: Quantitative Real-Time PCR was used to estimate expression of miR-485-3p and AKT3. A ROC analysis was used to evaluate the diagnostic value of miR-485-3p. The correlation of miR-485-3p with patients' MMSE score and inflammatory response was analyzed. Using Aß-treated SH-SY5Y and BV2 cells models, the effects of miR-485-3p on neuronal proliferation, apoptosis, and neuroinflammation were explored. A luciferase reporter assay was used to confirm the target gene of miR-485-3p in both SH-SY5Y and BV2 cells. RESULTS: Serum miR-485-3p expression was significantly upregulated in AD patients and cell models, which had a high diagnostic accuracy and correlated with MMSE score and inflammatory response in AD patients. The knockdown of miR-485-3p in SH-SY5Y and BV2 cells was found to significantly reverse the effect of Aß treatment on neuronal viability and neuroinflammation. AKT3 was determined as a target of miR-485-3p, which might mediate the biological function of miR-485-3p in AD pathogenesis. CONCLUSION: All the data indicated that increased serum miR-485-3p serves as a diagnostic biomarker in AD patients, and knockdown of miR-485-3p exerts a neuroprotective role by improving neuronal viability and weakening neuroinflammation, which may be mediated by AKT3. This study may provide a novel biomarker and therapeutic target for AD therapy.

Carrier Dynamic Investigations of AlGaInAs Quantum Well Revealed by Temperature-Dependent Time-Resolved Photoluminescence.

AlGaInAs quantum well (QW) lasers have great potential in the application fields of optical communications and eye-safety lidars, owing to the advantages of good gain performance. A large amount of experimental evidence indicated that carrier dynamic affects the resonant frequency and modulation response performance of QW lasers. However, the mechanism of carrier dynamic in AlGaInAs QW structure is still ambiguous for complicated artificial multilayers. In this paper, the carrier dynamic of AlGaInAs QW structure was investigated by temperature-dependent time-resolved photoluminescence (TRPL) in the range of 14 to 300 K. Two relaxation times (a fast component and a slow one) have a major impact on the PL emission spectra of the AlGaInAs QW below 200 K. The carriers prefer a fast decay channel in the low temperature regime, whereas the slow one a higher temperature. An unconventional temperature dependence of carrier relaxation is observed in both decay processes. The carriers' lifetime decreases with the temperature increasing till 45 K and then increases with temperature up to 250 K. It is quite different from that in the bulk semiconductor. The mechanism of temperature-dependent carrier relaxation at temperatures above 45 K is a combination of dark state occupation and a nonradiative recombination process.

Modulation of Field-Effect Passivation at the Back Electrode Interface Enabling Efficient Kesterite-Type Cu2ZnSn(S,Se)4 Thin-Film Solar Cells.

For further efficiency improvement in kesterite-type Cu2ZnSn(S,Se)4 (CZTSSe) solar cells, it is essential to address the carrier recombination issue at the back electrode interface (BEI) caused by the undesirable built-in potential orientation toward an absorber as an n-MoSe2 interfacial layer formed. In this regard, back surface field (BSF) incorporation, i.e., field-effect passivation, shows promise for dealing with this issue due to its positive effect in decreasing recombination at the BEI. In this study, the BSF was realized with the p-type conduction transition in interfacial layer MoSe2 by incorporating Nb into the back electrode. The BSF width can be tuned via modulating the carrier concentration of the absorber, which has been demonstrated by capacitance-voltage characterization. A beyond 7% efficiency BSF-applied CZTSSe solar cell is prepared, and the effects of a tunable BSF and the mechanism underpinning device performance improvement have been investigated in detail. The wider BSF distribution in the absorber induces a decrease in reverse saturation current density (J0) due to the stronger BSF effect in suppressing BEI recombination. As a result, an accompanying increase in open-circuit voltage (VOC) and short-circuit current density (JSC) is achieved as compared to the BSF-free case. This study offers an alternative strategy to address the BEI recombination issue and also broadens the interface passivation research scope of potentially competitive kesterite solar cells.

Acute coordinative exercise ameliorates general and food-cue related cognitive function in obese adolescents.

Whether the acute coordinative exercise could affect the inhibitory control and food-cue related attention in obese adolescents remains understudied. Therefore, this study used the Stroop test and the food-cue related Stroop test to explore the impacts of 20 min of acute coordinative exercise on the cognitive tests involving inhibitory control and attentional bias towards food-cue related stimuli, respectively, in obese adolescents. Thirty-eight obese adolescents (mean age = 14.63 ± 0.69 years) were equally divided into exercise and control groups. The cognitive tests (i.e., the Stroop test and the food-cue related Stroop test) and hunger scores were conducted and assessed before and after an intervention. The exercise group had significantly larger negative pre-post response time difference in the congruent (-1.04 ± 0.29 ms) and incongruent (-5.76 ± 1.66 ms) conditions of the Stroop test than the control group (ps < 0.01), and a smaller post-interference (1.13 ± 0.14) than the pre-interference (1.31 ± 0.14, p = 0.04). Moreover, a significantly larger negative pre-post response time difference on the food-cue related Stroop test was observed in the exercise group (-4.42 ± 7.20 ms) than the control group (1.76 ± 8.37 ms, p = 0.02). Collectively, an acute coordinative exercise session could induce superior inhibitory control and less attentional bias towards food-cue related stimuli in obese adolescents.

Self-Organized Back Surface Field to Improve the Performance of Cu2ZnSn(S,Se)4 Solar Cells by Applying P-Type MoSe2:Nb to the Back Electrode Interface.

Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells have been encountering a bottleneck period since the champion power conversion efficiency (PCE) of 12.7% was achieved by Kim et al. in 2014. One of the critical factors that impede its further development is the relatively low open-circuit voltage (VOC) caused by serious interface carrier recombination. In this regard, back surface field (BSF) employment is a feasible strategy to address the VOC issue of CZTSSe solar cells to some extent. Here, we demonstrated a self-organized BSF introduced by prompting interfacial MoSe2 layer transition from inherent n-type to desirable p-type with Nb doping (p-MoSe2:Nb). The BSF application can significantly reduce the carrier recombination at the back electrode interface (BEI) and lower down the back contact barrier height. The PCE of the corresponding cell was improved from 4.72 to 7.15% because of the enhancement of VOC and fill factor, primarily stemming from the doubling aspects of increased shunt resistance (RSh), decreased series resistance (RS), and alleviative recombination velocity of the BEI induced by the BSF. Our results suggest that introducing a BSF fulfilled with p-MoSe2:Nb is a facile and promising route to improve the performance of CZTSSe thin-film solar cells.

Cognitive Decline in Asymptomatic Middle Cerebral Artery Stenosis Patients with Moderate and Poor Collaterals: A 2-Year Follow-Up Study.

BACKGROUND The aim of this study was to determine whether poor collaterals contribute to the occurrence of certain types of cognitive disorders in asymptomatic middle cerebral artery stenosis (MCAS). MATERIAL AND METHODS Patients aged ≥45 years with asymptomatic MCAS confirmed by computed tomography angiography were included in a single-center retrospective study. They did not have prior stroke or dementia. Within 7 days of admission, MRI and comprehensive neuropsychological assessment were performed. Cognitive assessment was conducted after 2 years. Two independent neuroradiologists evaluated intracranial collaterals by using the Miteff scale. Demographic date and Fazekas scores were collected. RESULTS A total of 173 patients with asymptomatic MCAS (66% men, mean age 59.4 years) and 42 controls (45% men, mean age 61.4 years) were enrolled. Executive function, attention, and information-processing speed in poor collateral circulation patients were more frequently and more often impaired than those in good collateral circulation patients. Throughout the study period, patients with poor collateral circulation had worse executive function, attention, and information-processing speed than those with moderate collateral circulation. Over time, MCAS patients with good collateral circulation did not show an association with cognitive function. CONCLUSIONS MCAS patients with moderate and poor collateral circulation have impairment of ≥1 cognitive domain over time. The affected domains are consistent with the profile of vascular cognitive impairment. Good collateral circulation is more important in patients with MCAS, and is associated with less risk of cognitive disorders.

Regulation of Proliferation and Epithelial-to-Mesenchymal Transition (EMT) of Gastric Cancer by ZEB1 via Modulating Wnt5a and Related Mechanisms.

BACKGROUND As a member of the zinc-finger E-box binding protein (ZEB) family, ZEB1 can modulate onset and progression of various tumors, but its regulatory effect or mechanism in GC has not been defined. MATERIAL AND METHODS GC tumor tissues and adjacent tissues were collected from GC patients across different TNM stages. Real-time PCR was used to measure ZEB1 expression to analyze its correlation with pathological features of tumors. Cultured GC cell lines SGC-7901 and MGC-803 were randomly assigned into control group, scramble group, and ZEB1 siRNA group. Real-time PCR was employed to analyze ZEB1 expression, and MTT approach was used to measure cell proliferation. Cell apoptosis was evaluated by flow cytometry. Wound healing assay was used to detect its effect on cell migration. Expression of E-cadherin and Vimentin involved in epithelial-to-mesenchymal transition (EMT) was measured by Western blot analysis, along with Wnt5a proteins. RESULTS GC tissues had upregulation of ZEB1 (P<0.05 compared to adjacent tissues), whose expression level was correlated with differentiation grade, lymph node metastasis, and tumor pathological stage (P<0.05). Transfection of ZEB1 siRNA into SGC-7901 or MGC-803 cells can suppress ZEB1 expression, inhibit tumor cell proliferation, enhance apoptosis, and inhibit cell migration. Transfected GC cells had higher E-cadherin expression and decreased Vimentin expression or Wnt5a expression (P<0.05 compared to the control group). CONCLUSIONS ZEB1 expression is increased in GC tumor tissues and is associated with pathological features. The downregulation of ZEB1 can facilitate cell apoptosis via mediating Wnt5a, further suppressing GC cell proliferation and migration, and reducing EMT occurrence.

Hydrothermal Synthesis and Upconversion Properties of About 19 nm Sc2O3: Er3+, Yb3+ Nanoparticles with Detailed Investigation of the Energy Transfer Mechanism.

The Sc2O3: Er3+, Yb3+ nanoparticles (NPs) with the size of about 19 nm were synthesized by a simple oleic acid-mediated hydrothermal (HT) process. X-ray diffraction (XRD), transmission electron microscopy (TEM), upconversion luminescence (UCL) spectra, and decay curves were used to characterize the resulting samples. The Sc2O3: Er3+, Yb3+ NPs made by HT method exhibit the stronger UCL, of which the red UCL are enhanced by a factor of 4, in comparison with those samples prepared by solvothermal (ST) method at the same optimized lanthanide ion concentrations. The UCL enhancement can be attributed to the reduced surface groups and longer lifetimes. Under 980 nm wavelength excitation, the decay curves of Er3+: (2H11/2, 4S3/2) → 4I15/2 and 4F9/2 → 4I15/2 emissions for Sc2O3: Er3+, Yb3+ NPs samples are both close to each other, resulting from the cross relaxation energy transfer from Er3+ to Yb3+, followed by an energy back transfer within the same Er3+-Yb3+ pair. Also, under the relatively low-power density, the slopes of the linear plots of log(I) vs. log(P) for red and green emissions are 2.5 and 2.1, implying the existence of three-photon processes. Our results indicate that Sc2O3: Er3+, Yb3+ NPs is an excellent material for achieving intense UCL with small size in the biological fields.

Investigation of Interface Effect on the Performance of CH3NH3PbCl3/ZnO UV Photodetectors.

Recent investigations indicate that the performance of organic-inorganic perovskite optoelectronic devices can be improved by combining the perovskites and the inorganic materials. However, very few studies have focused on the investigation of perovskites/inorganic semiconductor hybrid UV photodetectors and their detailed performance-enhancement mechanism is still not very clear. In this work, a CH3NH3PbCl3/ZnO UV photodetector has been first demonstrated and investigated. Both the photoresponsivity and response speed of the hybrid device are higher than those of pure CH3NH3PbCl3 and ZnO devices. The photoluminescence and transient absorption spectra indicate that the photoinduced electron transfer between CH3NH3PbCl3 and ZnO should be responsible for the performance enhancement of the hybrid device. In addition, the high crystal quality of CH3NH3PbCl3 on ZnO film is another important reason for the excellent UV detection performance. Our findings in this work provide new insights into the intrinsic photophysics essential for perovskite optoelectronic devices.

TLR-4/microRNA-125a/NF-κB signaling modulates the immune response to Mycobacterium tuberculosis infection.

Tuberculosis (TB), caused by Mycobacterium tuberculosis, could lead to kinds of clinical disorders and remains a leading global health problem, resulting in great morbidity and mortality worldwide. Previous studies have firmly demonstrated that M. tuberculosis (M.tb) has evolved to utilize different mechanisms to evade or attenuate the host immune response, such as regulation of immune-related genes by modulation of miRNAs of host or bacteria. However, the knowledge of functions of miRNAs during M.tb infection remains limited. Here, we reported that a host microRNA, miR-125a, was significantly up-regulated by M.tb infection in both RAW264.7 and THP-1cells, in a TLR4 signaling-dependent manner. Subsequently, our results demonstrated that miR-125a was a negative regulator of NF-kB pathway by directly targeting TRAF6, resulting in the suppression of cytokines, attenuation of immune response and promotion of M.tb survival. Taken together, our findings provide a novel detailed molecular mechanism in which miR-125a was enhanced to inhibit inflammatory cytokines secretion and attenuate the immune response during M.tb infection in RAW264.7 and THP-1 cells, and suggest an intrinsic a promising anti-M.tb therapeutic target.

Efficient Blue-emitting Phosphor SrLu2O4:Ce3+ with High Thermal Stability for Near Ultraviolet (~400 nm) LED-Chip based White LEDs.

Blue-emitting phosphors for near ultraviolet (NUV) based tri-color RGB phosphor blend converted white light emitting diodes (LEDs) have been extensively investigated in the past few years. LED chip peaked near 400 nm is the most efficient among the NUV chips currently. However, most of blue phosphors show inefficient excitation around 400 nm. Herein, a novel blue phosphor SrLu2O4:Ce3+ matching well with near 400 nm chip and showing high thermal stability has been developed. The photoluminescence spectrum presents a broad emission band peaking at 460 nm with a bandwidth of nearly 90 nm. By optimizing the Ce3+ concentration, an internal quantum efficiency (IQE) as high as 76% was achieved. Furthermore, 86% of the room-temperature emission intensity is still maintained at 150 °C, indicating a good thermal stability and practicality. A series of white LEDs were fabricated based on 405 nm chips coated with a blend of the new blue phosphor with the commercial yellow and red phosphors. High color rendering indexes (≥90) were achieved while the correlated color temperature was tuneable in the range of 3094 to 8990 K. These results suggest that SrLu2O4:Ce3+ can be utilized as a blue-emitting phosphor in NUV based white LEDs.

RETRACTED: Astragaloside IV reduces the hypoxia-induced injury in PC-12 cells by inhibiting expression of miR-124.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. Given the comments of Dr Elisabeth Bik regarding this article "… the Western blot bands in all 400+ papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated", the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article.

Microscopic View of Defect Evolution in Thermal Treated AlGaInAs Quantum Well Revealed by Spatially Resolved Cathodoluminescence.

An aluminum gallium indium arsenic (AlGaInAs) material system is indispensable as the active layer of diode lasers emitting at 1310 or 1550 nm, which are used in optical fiber communications. However, the course of the high-temperature instability of a quantum well structure, which is closely related to the diffusion of indium atoms, is still not clear due to the system’s complexity. The diffusion process of indium atoms was simulated by thermal treatment, and the changes in the optical and structural properties of an AlGaInAs quantum well are investigated in this paper. Compressive strained Al0.07Ga0.22In0.71As quantum wells were treated at 170 °C with different heat durations. A significant decrement of photoluminescence decay time was observed on the quantum well of a sample that was annealed after 4 h. The microscopic cathodoluminescent (CL) spectra of these quantum wells were measured by scanning electron microscope-cathodoluminescence (SEM-CL). The thermal treatment effect on quantum wells was characterized via CL emission peak wavelength and energy density distribution, which were obtained by spatially resolved cathodoluminescence. The defect area was clearly observed in the Al0.07Ga0.22In0.71As quantum wells layer after thermal treatment. CL emissions from the defect core have higher emission energy than those from the defect-free regions. The defect core distribution, which was associated with indium segregation gradient distribution, showed asymmetric character.