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Anion-intercalation lithium metal batteries (AILMBs) are appealing due to their low cost and fast intercalation/de-intercalation kinetics of graphite cathodes. However, the safety and cycliability of existing AILMBs are constrained by the scarcity of compatible electrolytes. Herein, we showcase that a difluoroester can be applied as electrolyte solvent to realize high-performance AILMBs, which not only endows high oxidation resistance, but also efficiently tunes the solvation shell to enable highly reversible and kinetically fast cathode reaction beyond the trifluoro counterpart. The difluoroester-based electrolyte demonstrates nonflammability, high ionic conductivity, and electrochemical stability, along with excellent electrode compatibility. The Li| |graphite AILMBs reach a high durability of 10000 cycles with only a 0.00128% capacity loss per cycle under fast-cycling of 1 A g−1, and retain ~63% of room-temperature capacity when discharging at −65 °C, meanwhile supply stable power output under deformation and overcharge conditions. The electrolyte design paves a promising path toward fast-rate, low-temperature, durable, and safe AILMBs. The authors report a difluoroester electrolyte to enhance anion intercalation lithium metal batteries (AILMBs), improving safety and cyclability. This enables cost-effective graphitic carbon cathodes, with high durability, stability, and performance. [ABSTRACT FROM AUTHOR]

Ordered layered structures serve as essential components in lithium (Li)-ion cathodes1–3. However, on charging, the inherently delicate Li-deficient frameworks become vulnerable to lattice strain and structural and/or chemo-mechanical degradation, resulting in rapid capacity deterioration and thus short battery life2,4. Here we report an approach that addresses these issues using the integration of chemical short-range disorder (CSRD) into oxide cathodes, which involves the localized distribution of elements in a crystalline lattice over spatial dimensions, spanning a few nearest-neighbour spacings. This is guided by fundamental principles of structural chemistry and achieved through an improved ceramic synthesis process. To demonstrate its viability, we showcase how the introduction of CSRD substantially affects the crystal structure of layered Li cobalt oxide cathodes. This is manifested in the transition metal environment and its interactions with oxygen, effectively preventing detrimental sliding of crystal slabs and structural deterioration during Li removal. Meanwhile, it affects the electronic structure, leading to improved electronic conductivity. These attributes are highly beneficial for Li-ion storage capabilities, markedly improving cycle life and rate capability. Moreover, we find that CSRD can be introduced in additional layered oxide materials through improved chemical co-doping, further illustrating its potential to enhance structural and electrochemical stability. These findings open up new avenues for the design of oxide cathodes, offering insights into the effects of CSRD on the crystal and electronic structure of advanced functional materials.The introduction of chemical short-range disorder substantially affects the crystal structure of layered lithium oxide cathodes, leading to improved charge transfer and structural stability. [ABSTRACT FROM AUTHOR]

Nickel-rich layered oxide cathodes promise ultrahigh energy density but is plagued by the mechanical failure of the secondary particle upon (de)lithiation. Existing approaches for alleviating the structural degradation could retard pulverization, yet fail to tune the stress distribution and root out the formation of cracks. Herein, we report a unique strategy to uniformize the stress distribution in secondary particle via Kirkendall effect to stabilize the core region during electrochemical cycling. Exotic metal/metalloid oxides (such as Al2O3 or SiO2) is introduced as the heterogeneous nucleation seeds for the preferential growth of the precursor. The calcination treatment afterwards generates a dopant-rich interior structure with central Kirkendall void, due to the different diffusivity between the exotic element and nickel atom. The resulting cathode material exhibits superior structural and electrochemical reversibility, thus contributing to a high specific energy density (based on cathode) of 660 Wh kg−1 after 500 cycles with a retention rate of 86%. This study suggests that uniformizing stress distribution represents a promising pathway to tackle the structural instability facing nickel-rich layered oxide cathodes. Nickel-rich layered oxide cathodes offer high energy density yet suffer from mechanical degradation during (de)lithiation. Here, the authors present a strategy that leverages the Kirkendall effect to equalize stress within the cathode particles, thereby stabilizing their structure and enhancing the cycling stability. [ABSTRACT FROM AUTHOR]

Low temperatures severely impair the performance of lithium-ion batteries, which demand powerful electrolytes with wide liquidity ranges, facilitated ion diffusion, and lower desolvation energy. The keys lie in establishing mild interactions between Li+ and solvent molecules internally, which are hard to achieve in commercial ethylene-carbonate based electrolytes. Herein, we tailor the solvation structure with low-ε solvent-dominated coordination, and unlock ethylene-carbonate via electronegativity regulation of carbonyl oxygen. The modified electrolyte exhibits high ion conductivity (1.46 mS·cm−1) at −90 °C, and remains liquid at −110 °C. Consequently, 4.5 V graphite-based pouch cells achieve ~98% capacity over 200 cycles at −10 °C without lithium dendrite. These cells also retain ~60% of their room-temperature discharge capacity at −70 °C, and miraculously retain discharge functionality even at ~−100 °C after being fully charged at 25 °C. This strategy of disrupting solvation dominance of ethylene-carbonate through molecular charge engineering, opens new avenues for advanced electrolyte design. Low-temperature operation remains challenging for batteries. Here, the authors report an electrolyte solvation structure design strategy to break solvation dominance of ethylene carbonate to facilitate the desolvation process that improves the low-temperature performance of lithium-ion batteries even below −100 °C. [ABSTRACT FROM AUTHOR]

Background and purpose: Efforts to improve nurses' physical and mental health are critical to ensuring the safety and quality of the healthcare system. Long-term studies targeting the relevancy of nurses' occupation characteristics with health conditions remain insufficient. This study aimed to examine the relationship between nurses' night shift and sleep problems and metabolic abnormalities risk. Methods: This study was a part of the National Nurse Health Study, an ambispective cohort study in China, in 2021. Based on an integration physical examination data system, this study carried out a retrospective analysis of 730 nurses from 2018 to 2020 and combined with a questionnaire survey in 2021. The STROBE guidelines were adopted for reporting. Results: In the 23 (23.0, 24.0) months follow-up, higher night shift load was associated with more sleep problems such as shortened sleep duration, sleep disorders, poor sleep quality, and sleep deprivation. Moreover, night shift load was associated with chronic diseases risk factors, increasing body mass index and body fat, with more night shift density, increasing the occurrence of low levels of high-density lipoprotein cholesterol, high triglyceride, triglyceride/high-density lipoprotein cholesterol ratio, and serum uric acid. Conclusion: The night shift load has become an occupational health concern, contributing to chronic diseases relevant metabolic risk factors and negative influence on sleep health. Focus on the strategies to improve the sleep quality of nurses undergoing night shift work, optimize work scheduling and ongoing monitor the relevant risk factors are essential to enhance the stability and well-being of the nursing workforce. Clinical Trials registration information: NCT04572347, on October 1, 2020. https://www.clinicaltrials.gov/ct2/show/NCT04572347 [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of MRI in the diagnosis and classification of fetal microtia. Methods: Ninety-five fetuses with suspected microtia based on ultrasound and MRI performed within 1 week were enrolled in this study. The diagnosis based on MRI was compared with postnatal diagnosis. Among the microtia cases suspected on the basis of MRI, mild and severe cases were further classified. In addition, external auditory canal (EAC) atresia was evaluated by MRI in 29 fetuses with a gestational age > 28 weeks, and the accuracy of MRI in the diagnosis and classification of microtia was determined. Results: Of 95 fetuses, 83 were considered to have microtia on the basis of MRI, 81 were confirmed to have microtia, and 14 were found to be normal according to postnatal diagnosis. Among 190 external ears in 95 fetuses, 40 ears were suspected to have mild microtia, and 52 ears were suspected to have severe microtia on the basis of MRI. According to the postnatal diagnosis, mild and severe microtia were confirmed in 43 and 49 ears, respectively. Among the 29 fetuses with a gestational age > 28 weeks, 23 ears were suspected to have EAC atresia according to MRI and 21 ears were ultimately confirmed to have EAC atresia. The accuracy of MRI in diagnosing microtia and EAC atresia was 93.68% and 93.10%, respectively. Conclusion: MRI shows good performance in diagnosing fetal microtia and has the potential to evaluate its severity on the basis of classification and EAC status. Clinical relevance statement: This study was aimed at investigating the role of MRI in the diagnosis and classification of fetal microtia. MRI shows good performance and can help evaluate microtia severity and EAC atresia, thus allowing for better clinical management. Key Points: • MRI is a useful adjunct to prenatal ultrasound. • MRI has a higher accuracy rate than ultrasound in diagnosing fetal microtia. • The accurate classification of fetal microtia and the diagnosis of external auditory canal atresia through MRI may help guide clinical management. [ABSTRACT FROM AUTHOR]

Direct band gap GeSn alloys have recently emerged as promising lasing source materials for monolithic integration on Si substrate. In this work, optically pumped mid-infrared GeSn lasers were studied with the observation of dual-wavelength lasing at 2187 nm and 2460 nm. Two simultaneous lasing regions include a GeSn buffer layer (bulk) and a SiGeSn/GeSn multiple quantum well structure that were grown seamlessly using a chemical vapor deposition reactor. The onset of dual lasing occurs at 420 kW/cm2. The wider bandgap SiGeSn partitioning barrier enables the independent operation of two gain regions. While the better performance device in terms of lower threshold may be obtained by using two MQW regions design, the preliminary results and discussions in this work paves a way towards all-group-IV dual wavelength lasers monolithically integrated on Si substrate. [ABSTRACT FROM AUTHOR]

Aims: To quantitatively analyze and compare the differences in retinal neurovascular units (NVUs) between healthy individuals and patients with type 2 diabetes mellitus (DM) by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) techniques and to determine the value of this technique for the early diagnosis of retinal neurovascular damage in patients with diabetes mellitus without retinopathy (NDR). Methods: This observational case‒control study was conducted from July 1, 2022, to November 30, 2022, at the outpatient ophthalmology clinic of the Affiliated Hospital of Shandong University of Traditional Chinese Medicine. All subjects underwent baseline data entry and mean thickness of the peripapillary retinal nerve fiber layer (pRNFL), the thickness of each retinal layer in the macula 3 × 3 mm, and vascular density (VD) examination. Results: The study included 35 healthy individuals and 48 patients with DM. The retinal VD as well as partial pRNFL, macular nerve fiber layer (NFL), and macular ganglion cell layer (GCL) thickness in DM patients exhibited significantly lower VD in the DM group than in the control group (p < 0.05). Age and disease duration of DM patients showed a negative trend with pRNFL thickness, macular NFL thickness, macular GCL thickness, and VD. However, a positive trend was observed between DM duration and partial inner nuclear layer (INL) thickness. Moreover, there was a positive correlation between macular NFL and GCL thickness and VD for the most part, while a negative correlation was shown between INL temporal thickness and DVC-VD. pRNFL-TI and GCL-superior thickness were screened as two variables in the analysis of the predictors of retinal damage in DM according to the presence or absence of DM. The AUCs were 0.765 and 0.673, respectively. By combining the two indicators for diagnosis, the model predicted prognosis with an AUC of 0.831. In the analysis of retinal damage indicators associated with the duration of DM, after regression logistic analysis according to the duration of DM within 5 years and more than 5 years, the model incorporated two indicators, DVC-VD and pRNFL-N thickness, and the AUCs were 0.764 and 0.852, respectively. Combining the two indicators for diagnosis, the AUC reached 0.925. Conclusions: Retinal NVU may have been compromised in patients with DM without retinopathy. Basic clinical information and rapid noninvasive OCT and OCTA techniques are useful for the quantitative assessment of retinal NVU prognosis in patients with DM without retinopathy. [ABSTRACT FROM AUTHOR]

Summary: Hip fractures represent a significant public health issue due to high incidence in aging society. Our study further proved that increased risk for hip fractures in adults is associated with weather conditions. Purpose: Hip fractures represent a significant public health issue due to high incidence in aging society. Evidence of the short-term effects of weather on the risk of hip fracture is limited and inconsistent. We aimed to examine the associations between weather conditions and daily hospital admissions for hip fracture in adults in China. Methods: A national time-series analysis between 2014 and 2017 was conducted. Data on daily hospital admissions for hip fracture were obtained from the database of Urban Employee Basic Medical Insurance (UEBMI) and Urban Resident Basic Medical Insurance (URBMI). Weather conditions were acquired from the China Meteorological Data Sharing Service Center. Based on a time-stratified case-crossover design, conditional Poisson regression was used to estimate the impact on relative risk (RR) of weather conditions on hospital admissions for hip fracture. Results: During the study period, a total of 137,504 hospital admissions for hip fractures were identified. All analyzed weather conditions showed consistent significant associations at lag 0 day for each 10 mm increase in precipitation, 10 m/s in wind speed, and 10°C in temperature, with the RR value being 1.079 (95% CI, 1.074–1.083) for precipitation, 1.404 (95% CI, 1.346–1.465) for wind speed, and 1.558 (95% CI, 1.546–1.570) for temperature. Women were more vulnerable to be affected by precipitation and temperature. Conclusion: In conclusion, increased risk for hip fractures in adults is associated with weather conditions. The improved understanding of the relationship between weather conditions and hip fractures hospital admission can be useful for resource allocation and provider preparedness. [ABSTRACT FROM AUTHOR]

Aqueous Zn-ion batteries have attracted increasing research interest; however, the development of these batteries has been hindered by several challenges, including dendrite growth, Zn corrosion, cathode material degradation, limited temperature adaptability and electrochemical stability window, which are associated with water activity and the solvation structure of electrolytes. Here we report that water activity is suppressed by increasing the electron density of the water protons through interactions with highly polar dimethylacetamide and trimethyl phosphate molecules. Meanwhile, the Zn corrosion in the hybrid electrolyte is mitigated, and the electrochemical stability window and the operating temperature of the electrolyte are extended. The dimethylacetamide alters the surface energy of Zn, guiding the (002) plane dominated deposition of Zn. Molecular dynamics simulation evidences Zn2+ ions are solvated with fewer water molecules, resulting in lower lattice strain in the NaV3O8·1.5H2O cathode during the insertion of hydrated Zn2+ ions, boosting the lifespan of Zn|| NaV3O8·1.5H2O cell to 3000 cycles. The electrochemical performance of aqueous zinc ion batteries is limited by water activity. Here, the authors propose a hybrid electrolyte that incorporate strongly polar molecules to strengthen the water O–H bonds, thus reduce water activity and improve the electrochemical performance of the batteries. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is the ultimate anode choice for next generation high energy density batteries. However, the high nucleation energy barrier and nonuniform electric field distribution, as well as huge volume expansion, lead to the uncontrollable growth of Li dendrites and poor utilization of Li metal, which hinders its practical application. Herein, titanium dioxide/cuprous oxide (TiO2/Cu2O) heterostructure is constructed on the rimous skeleton of Cu mesh, and the heterostructure decorated rimous Cu mesh (H-CM) can act as both current collector and host for dendrite-free Li metal anode. The TiO2/Cu2O heterostructure realizes selective Li nucleation by nano TiO2 and then induces fast and uniform Li conduction with the aid of heterostructure interface and nano Cu2O contributing to dendrite-free Li deposition. While the internal and external space of rimous skeletons in H-CM is used to accommodate the deposited Li and buffer its volume change. Therefore, the cycling reversibility of the derived Li metal anode in H-CM is improved to a high Coulombic efficiency of 98.8% for more than 350 cycles at a current density of 1 mA·cm−2, and 1,000 h (equals to 500 cycles) stable repeated Li plating/stripping can be operated in a symmetric cell. Furthermore, full cells with limited Li anode and high loading LiFePO4 cathode present excellent cycling and rate performances. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the potential association between trace elements and latent tuberculosis infection (LTBI) based on the data from the National Health and Nutritional Examination Survey (NHANES) during 2011–2012. In this cross-sectional study, tuberculin skin testing (TST) and QuantiFERON®-TB Gold In-Tube (QFT-GIT) were utilized to screen for LTBI. Participants with positive results of TST or/and QFT-GIT were defined as LTBI. Weighted univariate and multivariate logistic regression analyses were used to explore the association between trace elements and LTBI. Subgroup analyses were conducted according to gender, age, birthplace, race, and health insurance holding status. A total of 6064 participants were included in this study, of whom 655 (10.80%) participants were with positive results of LTBI. Weighted multivariable analysis demonstrated that zinc [odds ratio (OR) = 0.89; 95% confidence interval (CI), 0.82–0.97] and selenium (OR = 0.31; 95%CI, 0.13–0.70) in the serum may be associated with a reduced risk of LTBI. In different concentrations of zinc and selenium, serum zinc concentration of 12.56–13.99 μmol/l (vs. < 11.23 μmol/l; OR = 0.37, 95% CI, 0.20–0.67) was related to a reduced risk of LTBI, while no significant difference was observed under different selenium levels (P > 0.05). Subgroup analyses indicated that the role of zinc and selenium in reducing TB risk may be more significant in males, people aged 21–64, people born in the USA, people with health insurance, and non-Hispanic Whites. Maintaining serum zinc and selenium levels may help reduce the risk of LTBI and indirectly help people prevent TB. [ABSTRACT FROM AUTHOR]

Rechargeable halide-ion batteries (HIBs) are good candidates for large-scale due to their appealing energy density, low cost, and dendrite-free features. However, state-of-the-art electrolytes limit the HIBs' performance and cycle life. Here, via experimental measurements and modelling approach, we demonstrate that the dissolutions in the electrolyte of transition metal and elemental halogen from the positive electrode and discharge products from the negative electrode cause the HIBs failure. To circumvent these issues, we propose the combination of fluorinated low-polarity solvents with a gelation treatment to prevent dissolutions at the interphase, thus, improving the HIBs' performance. Using this approach, we develop a quasi-solid-state Cl-ion-conducting gel polymer electrolyte. This electrolyte is tested in a single-layer pouch cell configuration with an iron oxychloride-based positive electrode and a lithium metal negative electrode at 25 °C and 125 mA g–1. The pouch delivers an initial discharge capacity of 210 mAh g–1 and a discharge capacity retention of almost 80% after 100 cycles. We also report assembly and testing of fluoride-ion and bromide-ion cells using quasi-solid-state halide-ion-conducting gel polymer electrolyte. State-of-the-art electrolytes limit the cycle life of halide-ion batteries. Here, the authors report a fluorinated low-polar gel polymer electrolyte capable of improving the stability of the electrolyte and electrode interphases to boost battery performance. [ABSTRACT FROM AUTHOR]

Highlights: A symbiotic host of porous graphite layer is designed as hybrid Li anode for Li ion intercalation and subsequent uniform plating. An ultrahigh plating reversibility of 99.5% is achieved in the carbonate electrolyte. An air-stable cathode prelithiation agent is introduced to provide extra Li source, resulting high energy density of the as-developed practical hybrid Li-ion/metal full cell.The energy density of commercial lithium (Li) ion batteries with graphite anode is reaching the limit. It is believed that directly utilizing Li metal as anode without a host could enhance the battery’s energy density to the maximum extent. However, the poor reversibility and infinite volume change of Li metal hinder the realistic implementation of Li metal in battery community. Herein, a commercially viable hybrid Li-ion/metal battery is realized by a coordinated strategy of symbiotic anode and prelithiated cathode. To be specific, a scalable template-removal method is developed to fabricate the porous graphite layer (PGL), which acts as a symbiotic host for Li ion intercalation and subsequent Li metal deposition due to the enhanced lithiophilicity and sufficient ion-conducting pathways. A continuous dissolution-deintercalation mechanism during delithiation process further ensures the elimination of dead Li. As a result, when the excess plating Li reaches 30%, the PGL could deliver an ultrahigh average Coulombic efficiency of 99.5% for 180 cycles with a capacity of 2.48 mAh cm−2 in traditional carbonate electrolyte. Meanwhile, an air-stable recrystallized lithium oxalate with high specific capacity (514.3 mAh g−1) and moderate operating potential (4.7–5.0 V) is introduced as a sacrificial cathode to compensate the initial loss and provide Li source for subsequent cycles. Based on the prelithiated cathode and initial Li-free symbiotic anode, under a practical-level 3 mAh capacity, the assembled hybrid Li-ion/metal full cell with a P/N ratio (capacity ratio of LiNi0.8Co0.1Mn0.1O2 to graphite) of 1.3 exhibits significantly improved capacity retention after 300 cycles, indicating its great potential for high-energy-density Li batteries. [ABSTRACT FROM AUTHOR]

Highlights: The effect of electrostatic interaction on regulating an anion-rich solvation in electrolyte is firstly proposed. The moderate electrostatic interaction between anion and solvent promotes anion-rich solvation sheath, inducing a stable electrolyte|electrode interface with fast Li+ transport kinetics. The outstanding electrochemical performance of 50 μm-thin Li||high-loading LiCoO2 batteries is achieved at high voltage of 4.5 V (even up to 4.6 V), lean electrolyte of 15 μL, and wide temperature range of − 20 to 60 °C.Through tailoring interfacial chemistry, electrolyte engineering is a facile yet effective strategy for high-performance lithium (Li) metal batteries, where the solvation structure is critical for interfacial chemistry. Herein, the effect of electrostatic interaction on regulating an anion-rich solvation is firstly proposed. The moderate electrostatic interaction between anion and solvent promotes anion to enter the solvation sheath, inducing stable solid electrolyte interphase with fast Li+ transport kinetics on the anode. This as-designed electrolyte exhibits excellent compatibility with Li metal anode (a Li deposition/stripping Coulombic efficiency of 99.3%) and high-voltage LiCoO2 cathode. Consequently, the 50 μm-thin Li||high-loading LiCoO2 cells achieve significantly improved cycling performance under stringent conditions of high voltage over 4.5 V, lean electrolyte, and wide temperature range (− 20 to 60 °C). This work inspires a groundbreaking strategy to manipulate the solvation structure through regulating the interactions of solvent and anion for high-performance Li metal batteries. [ABSTRACT FROM AUTHOR]

Owing to the conductance-adjustable performance, the emerging two-terminal memristors are promising candidates for artificial synapses and brain-spired neuromorphic computing. Although memristors based on molybdenum disulfide (MoS2) have displayed outstanding performance, such as thermal stability and high energy efficiency, reports on memristors based on MoS2 as the functional layer to simulate synaptic behavior are limited. Herein, a homologous Mo2C/MoS2-based memristor is prepared by partially sulfuring two-dimensional Mo2C crystal. The memristor shows good stability, excellent retention (~104 s) and endurance (>100 cycles), and a high ON/OFF ratio (>103). Moreover, for comprehensively mimicking biological synapses, the essential synaptic functions of the device are systematically analyzed, including paired-pulse facilitation (PPF), short-term plasticity (STP), long-term plasticity (LTP), long-term depression (LTD), and the transitions from STP to LTP. Notably, this artificial synapse could keep a high-level stable memory for a long time (60 s) after repeated stimulation. These results prove that our device is highly desirable for biological synapses, which show great potential for application in future high-density storage and neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

The topology management classifiers consist of several methods, such as the typical clustering-based method excelled in wireless network partitioning. However, most algorithms appear load unbalanced in the application of irregular network, resulting "energy hot zone" phenomenon. This paper proposes an improved intelligent clustering algorithm and applies it to the complex water system environment. Firstly, we build a new energy consumption model for wireless transmission network, and design a genetic clustering strategy via the minimum energy consumption principle. Secondly, we introduce the P matrix coding approach considering the search scale, so as to avoid the squared increasing relationship between the searching space and the data calculation. Thirdly, we employ adaptive genetic operator to enhance the directivity of the searching space, and utilize a fuzzy modified operator to enhance the accuracy of the cluster head selection, which may ensure the iterative efficiency. Through numerical simulations, empirical results show better performance than traditional methods in load balancing and clustering efficiency, which can effectively improve the network convergence speed and extend the network lifetime. [ABSTRACT FROM AUTHOR]

A key challenge for solid-state-batteries development is to design electrode-electrolyte interfaces that combine (electro)chemical and mechanical stability with facile Li-ion transport. However, while the solid-electrolyte/electrode interfacial area should be maximized to facilitate the transport of high electrical currents on the one hand, on the other hand, this area should be minimized to reduce the parasitic interfacial reactions and promote the overall cell stability. To improve these aspects simultaneously, we report the use of an interfacial inorganic coating and the study of its impact on the local Li-ion transport over the grain boundaries. Via exchange-NMR measurements, we quantify the equilibrium between the various phases present at the interface between an S-based positive electrode and an inorganic solid-electrolyte. We also demonstrate the beneficial effect of the LiI coating on the all-solid-state cell performances, which leads to efficient sulfur activation and prevention of solid-electrolyte decomposition. Finally, we report 200 cycles with a stable capacity of around 600 mAh g−1 at 0.264 mA cm−2 for a full lab-scale cell comprising of LiI-coated Li2S-based cathode, Li-In alloy anode and Li6PS5Cl solid electrolyte. Development of all-solid-state batteries requires stable solid electrolyte-electrode interfaces. Here, via exchange-NMR measurements, the authors investigate the positive electrode-solid electrolyte interface, revealing the impact of an inorganic coating on the Li-ion transport properties. [ABSTRACT FROM AUTHOR]

The current Li-based battery technology is limited in terms of energy contents. Therefore, several approaches are considered to improve the energy density of these energy storage devices. Here, we report the combination of a heteroatom-based gel polymer electrolyte with a hybrid cathode comprising of a Li-rich oxide active material and graphite conductive agent to produce a high-energy "shuttle-relay" Li metal battery, where additional capacity is generated from the electrolyte's anion shuttling at high voltages. The gel polymer electrolyte, prepared via in situ polymerization in an all-fluorinated electrolyte, shows adequate ionic conductivity (around 2 mS cm−1 at 25 °C), oxidation stability (up to 5.5 V vs Li/Li+), compatibility with Li metal and safety aspects (i.e., non-flammability). The polymeric electrolyte allows for a reversible insertion of hexafluorophosphate anions into the conductive graphite (i.e., dual-ion mechanism) after the removal of Li ions from Li-rich oxide (i.e., rocking-chair mechanism). The energy content increase is of paramount importance for the development of future Li-based batteries. Here, the authors propose a gel polymer electrolyte in combination with a positive electrode comprising of a Li-rich oxide active material and graphite to produce a high-energy Li metal cell. [ABSTRACT FROM AUTHOR]

The increase in the area treated with the insecticide fipronil has caused concern for aquatic organisms such as fish. Here, we assessed the effect of fipronil on carp indexes of non-specific immunity, oxidative stress, autophagy, and apoptosis following exposure to 0.074 mg/L and 0.185 mg/L of fipronil in the aqueous environment for 1 day, 3 days, 5 days, and 7 days. It was found that glutathione (GSH), malonaldehyde (MDA), and superoxide dismutase (SOD) in gills were significantly reduced (P < 0.05). The increase in exposure time increases the impact on GSH, SOD, and MDA parameters in the liver and intestine. Liver acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LZM) activity levels increased significantly in the treatment group on the first day after exposure, except for the 0.074 mg/L group of ACP (P < 0.05). The mRNA expression levels of autophagy-related genes ATG12, ATG5, ATG16L, LC3-II, and BECN1 were generally elevated in the liver and intestine during the initial exposure period (P < 0.05), while mTOR was significantly reduced on the first and third days after treatment (P < 0.05). From the results of Western blotting (WB), we can see that the amount of LC3-II was significantly higher than that of LC3-I at 1, 3, and 5 days of exposure (P < 0.05). Furthermore, the apoptosis-related gene Bcl-2 reached its peak in the liver, intestine, and gill on the first day, and caspase3 was significantly downregulated throughout the exposure period (P < 0.05). The results showed that fipronil was potentially harmful to carp and should be used moderately to reduce the damage to aquatic ecosystems. This study complements the mechanism theory of fipronil on fish toxicology and has a certain value for human health risk assessment. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the basic principle of the Brillouin optical time domain analysis (BOTDA) system and simulate the gain-type BOTDA system. In order to extract the Brillouin frequency shift more accurately, the filtering method is vitally important. In this letter, Gaussian filtering, median filtering and hybrid filtering are used to remove the noise respectively. It is observed that hybrid filtering has the best performance among the three methods, which can improve the signal-to-noise ratio by 9.18 dB. Besides, a peak location method is proposed to quickly extract the center frequency of the filtered Brillouin gain spectrum. This method reduces processing complexity by omitting Lorentz fitting and it possesses the advantages of fast processing rate and high accuracy. Therefore, the peak location method we proposed can be considered as an attractive method for extracting temperature distributions. [ABSTRACT FROM AUTHOR]

Congenital facio-cervical masses can be a developmental anomaly of cystic, solid, or vascular origin, and have an inseparable relationship with adverse prognosis. This retrospective cross-sectional study aimed at determining on the prenatal diagnosis of congenital facio-cervical masses, its management and outcome in a large tertiary referral center. We collected information on prenatal clinical data, pregnancy outcomes, survival information, and final diagnosis. Out of 130 cases of facio-cervical masses, a total of 119 cases of lymphatic malformations (LMs), 2 cases of teratoma, 2 cases of thyroglossal duct cyst, 4 cases of hemangioma, 1 case of congenital epulis, and 2 cases of dermoid cyst were reviewed. The accuracy of prenatal ultrasound was 93.85% (122/130). Observations of diameters using prenatal ultrasound revealed that the bigger the initial diameter is, the bigger the relative change during pregnancy. Magnetic resonance imaging (MRI) revealed that 2 cases of masses were associated with airway compression. In conclusion, ultrasound has a high overall diagnostic accuracy of fetal face and neck deformities. Prenatal US can enhance the management of ambulatory monitoring and classification. Furthermore, MRI provided a detailed assessment of fetal congenital malformations, as well as visualization of the trachea, presenting a multi-dimensional anatomical relationship. [ABSTRACT FROM AUTHOR]

Earlier literature suggests that ovarian preservation in young premenopausal clinical stage I endometrioid endometrial carcinoma patients does not negatively impact prognosis. The main purpose of this study was to clarify the incidence of ovarian malignant involvement in this group and further identify potential preoperative predictive factors of ovarian malignant involvement. A total of 511 premenopausal (age ≤ 50 years) patients were enrolled for the study at Women's Hospital, Zhejiang University School of Medicine, between January 2002 and December 2016. Ovarian malignant involvements were detected in 23 of the patients (4.5%). Univariate and multivariate logistic analysis validated preoperative imaging of myometrial invasion depth and preoperative serum carbohydrate antigen 125 (CA125) level as independent risk predictors of postoperative ovarian malignant involvement. Receiver operating characteristic (ROC) curves was generated for a combination of the two factors. The area under curve (AUC) was 0.772 (95% confidence interval [CI] 0.661–0.884) for the combined two factors. The incidence of postoperative ovarian malignant involvement was relatively minimal. Preoperative imaging of myometrial invasion depth and serum CA125 level were independent risk predictors of ovarian malignant involvement. These findings may facilitate preoperative counseling of patients and informed clinical decision-making on ovarian preservation in these patients. [ABSTRACT FROM AUTHOR]

Purpose: To translate the International Consultation of Incontinence Questionnaire (ICIQ)-bladder diary into Chinese and validate it among Chinese women with lower urinary tract symptoms. Methods: After receiving permission to translate and validate the ICIQ-bladder diary from Bristol Urological Institute, a Chinese ICIQ-bladder diary was developed through translation, re-translation and cultural adaption. Subsequently, we tested its reliability, validity and responsiveness and evaluated its optimal record duration among females with lower urinary tract symptoms. Results: A total of 146 participants were recruited in the study. We interviewed eight women about the content and format of the ICIQ-bladder diary, and they all thought it was clear and easy to use. Nineteen women completed the ICIQ-bladder diary twice with a 2-week interval. The resulting agreement of each item fluctuated between 0.582 and 0.940. A total of 11 urologists and nurses evaluated its content validity, and the experts' authority was 0.94 ± 0.06. The item content validity index of the ICIQ-bladder diary was 0.909–1.000, and the scale content validity index was 0.974. Another 22 women recorded their information in the ICIQ-bladder diary pre- and post-treatment, which showed a significant difference (P < 0.01), demonstrating rigorous responsiveness. Eighty-six women completed the ICIQ-bladder diary for 4 days, and the optimal duration of the ICIQ-bladder diary was tested as 3 days. Conclusions: The Chinese ICIQ-bladder diary demonstrates good stability, strong content validity and rigorous responsiveness among Chinese women with lower urinary tract symptoms. [ABSTRACT FROM AUTHOR]

Porous Si can be synthesized from diverse silica (SiO2) via magnesiothermic reduction technology and widely employed as potential anode material in lithium ion batteries. However, concerns regarding the influence of residual silicon oxide (SiOx) component on resulted Si anode after reduction are still lacked. In this work, we intentionally fabricate a cauliflower-like silicon/silicon oxide (CF-Si/SiOx) particles from highly porous SiO2 spheres through insufficient magnesiothermic reduction, where residual SiOx component and internal space play an important role in preventing the structural deformation of secondary bulk and restraining the expansion of Si phase. Moreover, the hierarchically structured CF-Si/SiOx exhibits uniformly-dispersed channels, which can improve ion transport and accommodate large volume expansion, simultaneously. As a result, the CF-Si/SiOx-700 anode shows excellent electrochemical performance with a specific capacity of ~1,400 mA·h·g−1 and a capacity retention of 98% after 100 cycles at the current of 0.2 A·g−1. [ABSTRACT FROM AUTHOR]

Silicon–germanium (SiGe) films have been grown using chemical vapor deposition on c-plane sapphire substrates. Optical and material characterization of the films show successful alloying of SiGe up to 22.4% Si. X-ray diffraction characterizations show that the SiGe films are oriented in the (111) direction on the sapphire (0001) substrates. However, 60°-rotated twin defects are observed as well. Transmission electron microscopy (TEM) shows crystalline growth of the film. The high surface roughness observed in the TEM images and the atomic force microscopy scans of the films indicates the formation of two different orientations of SiGe on sapphire substrates. [ABSTRACT FROM AUTHOR]

Efficient thermal dissipation is one of the most critical factors constraining the development of modern microelectronic devices. Placing vertically aligned carbon nanotubes (VACNTs) with anisotropic thermal conductive between high-power devices and heat sink such as copper plate can improve the interfacial thermal conductance. Due to the limited contact area between CNTs and the surface of the devices, direct use of ACNTs as thermal interface material fails to meet people's expectations. Here, we employ reduced graphene oxide (rGO) as the substrate for the growth of CNT arrays. VACNTs grown on rGO (rGO-ACNT) by chemical vapor deposition are then used as thermal conducting filler in epoxy resin. Compared with direct contact between CNT and the interface, using CNT and reduced graphene oxide junction to form contact with the surface can improve heat transfer efficiency. The resultant composite film exhibited excellent thermal conductivity at 9.62 W m−1 K−1 along the thickness direction. The obtained rGO-ACNT and its composite present higher thermal conductivity and heat transfer ability than ACNT. This strategy offers an insight into the easy preparation of flexible and highly thermal conductive composite materials, which may enable potential applications in advanced electronic devices. [ABSTRACT FROM AUTHOR]

Purpose: Persistent infection with high-risk human papillomavirus (HR-HPV) is thought to play a prominent role in the initiation and progression of almost all cases of cervical cancer. Previously, we and others found that microRNA 34a (miR-34a) may be regulated by HR-HPV E6 to contribute to the development of cervical cancer. Here, we aimed to identify the oncogenic potential and clinical significance of a known miR-34a target, WNT1, in cervical squamous cell carcinoma (SCC) development and to investigate the associated mechanisms underlying cervical SCC cell proliferation and invasion. Methods: WNT1 and miR-34a expression levels were assessed in primary cervical lesions using immunohistochemistry and qRT-PCR, respectively. The cellular effects and the expression of its associated genes were examined in cervical SCC-derived Siha and Caski cells after siRNA-WNT1 (downregulation) or miR-34a mimic (upregulation) treatment. A cervical SCC xenograft mouse model was used to investigate the in vivo effects of miR-34a overexpression. HPV-16 E6/E7 expression was inhibited by gene promoter siRNA targeting, after which the levels of miR-34a and WNT1 were examined. Results: WNT1 protein upregulation was found to be associated with a poor prognosis in cervical SCC patients. In vitro assays in Siha and Caski cells revealed that WNT1 downregulation decreased cell proliferation and invasion, inhibited WNT/β-catenin activation and affected the expression of E-cadherin and P-cadherin. MiR-34a upregulation resulted in decreased WNT1 expression. An inverse correlation between miR-34a and WNT1 expression was also observed in primary cervical SCC tissues. In addition, we found that MiR-34a could regulate an E-cadherin to P-cadherin switch (E-P cadherin switch) to inhibit cell proliferation and tumorigenesis in vitro and in vivo via inactivation of the WNT1/β-catenin pathway. Finally, we found that decreased HPV-16 E6/E7 expression resulted in miR-34a upregulation and WNT1 downregulation in Siha and Caski cells. Conclusions: From our results we conclude that WNT1, as a target of miR-34a, can promote cervical SCC cell proliferation and invasion by induction of an E-P cadherin switch via the WNT1/β-catenin pathway. Our results may provide new options for the treatment of patients with cervical SCC. [ABSTRACT FROM AUTHOR]

Glomerella leaf spot (GLS) has been found on apple trees in China since 2011 and severely affects apple production (Malus domestica Borkh.). The fungus that causes GLS, Glomerella cingulata (Stoneman) Spauld. & H.Schrenk, is epidemic in regions with humid climates each year. It can spread more than 200 km per year, and within the last several years has been found in most apple-producing areas in China. To investigate the origin, evolution and diversity of G. cingulata for better GLS management, we sequenced the whole genome of G. cingulata isolate 030206 and scanned simple sequence repeat (SSR) motifs in the genome. Then we constructed an SSR marker library containing 844 markers and their primers for amplifying the makers. We selected 25 prime pairs to test 96 G. cingulata isolates gathered from eight areas in Shandong Province, China, where GLS is prevalent and proved that the SSR markers were polymorphic among the tested isolates and were informative for analyzing genetic diversity. Developing SSR markers for G. cingulata using the whole-genome sequence is an efficient strategy for genetic diversity analysis, and the library of SSR marker constructed in this study should aid the identification of G. cingulata. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the value of MRI in the prenatal diagnosis and classification of cleft palate (CP).Methods: We collected 94 fetal cases that were suspected of cleft palate with or without cleft lip by prenatal ultrasound (US) and then carried out further MRI to examine the entire body of each fetus within 1 week. The diagnoses resulting from MRI and US examination were compared separately with the final diagnoses obtained from postnatal physical examination or fetal autopsy. The diagnostic accuracy between MRI and US was then determined.Results: During the follow-up period, the results for 6 fetuses (6.38%) were lost. Of the remaining 88 cases, the final diagnoses identified 23 cases of cleft lip (CL), 45 cases of unilateral cleft lip with cleft palate (UCLP), 4 cases of median cleft lip with cleft palate (MCLP), 12 cases of bilateral cleft lip with cleft palate (BCLP), 3 cases of unilateral cleft lip and cleft alveolus (CLA), and 1 case of isolated cleft palate (CPO). The total accuracy rate of US was 59.09%, while that of MRI was 92.05%. More importantly, 81 cases were accurately identified by MRI; the accuracy rate for CL, UCLP, MCLP, BCLP, CLA, and CPO was 86.96%, 95.56%, 100%, 91.67%, 66.67%, and 100%, respectively.Conclusion: Our results suggest that MRI could be a useful adjunct to US examination in the prenatal diagnosis of fetuses with cleft palate, and further demonstrates the classification and degree of involvement of the cleft palate.Key Points: • MRI is a useful adjunct to prenatal ultrasound. • MRI has a higher accuracy rate for CP. • The accurate classification of CP diagnosed by MRI can guide clinical management. [ABSTRACT FROM AUTHOR]

Nitrogen is an essential macronutrient for plant growth and basic metabolic processes. The application of nitrogen-containing fertilizer increases yield, which has been a substantial factor in the green revolution1. Ecologically, however, excessive application of fertilizer has disastrous effects such as eutrophication2. A better understanding of how plants regulate nitrogen metabolism is critical to increase plant yield and reduce fertilizer overuse. Here we present a transcriptional regulatory network and twenty-one transcription factors that regulate the architecture of root and shoot systems in response to changes in nitrogen availability. Genetic perturbation of a subset of these transcription factors revealed coordinate transcriptional regulation of enzymes involved in nitrogen metabolism. Transcriptional regulators in the network are transcriptionally modified by feedback via genetic perturbation of nitrogen metabolism. The network, genes and gene-regulatory modules identified here will prove critical to increasing agricultural productivity. The yeast one-hybrid network for nitrogen-associated metabolism in Arabidopsis reveals the transcription factors that regulate the architecture of root and shoot systems under conditions of changing nitrogen availability. [ABSTRACT FROM AUTHOR]

Germanium (Ge) films have been grown on silicon (Si) substrate by ultrahigh-vacuum chemical vapor deposition with plasma enhancement (PE). Argon plasma was generated using high-power radiofrequency (50 W) to assist in germane decomposition at low temperature. The growth temperature was varied in the low range of 250°C to 450°C to make this growth process compatible with complementary metal-oxide-semiconductor technology. The material and optical properties of the grown Ge films were investigated. The material quality was determined by Raman and x-ray diffraction techniques, revealing growth of crystalline films in the temperature range of 350°C to 450°C. Photoluminescence spectra revealed improved optical quality at growth temperatures of 400°C and 450°C. Furthermore, material quality study using transmission electron microscopy revealed existence of defects in the Ge layer grown at 400°C. Based on the etch pit density, the average threading dislocation density in the Ge layer obtained at this growth temperature was measured to be 4.5 × 108 cm−2. This result was achieved without any material improvement steps such as use of graded buffer or thermal annealing. Comparison between PE and non-plasma-enhanced growth, in the same machine at otherwise the same growth conditions, indicated increased growth rate and improved material and optical qualities for PE growth. [ABSTRACT FROM AUTHOR]

Key message: ILR3 and PYE function in a regulatory network that modulates GLS accumulation under iron deficiency.Abstract: The molecular processes involved in the cross talk between iron (Fe) homeostasis and other metabolic processes in plants are poorly understood. In Arabidopsis thaliana the transcription factor IAA-LEUCINE RESISTANT3 (ILR3) regulates iron deficiency response, aliphatic glucosinolate (GLS) biosynthesis and pathogen response. ILR3 is also known to interact with its homolog, POPEYE (PYE), which also plays a role in Fe response. However, little is known about how ILR3 regulates such diverse processes, particularly, via its interaction with PYE. Since GLS are produced as part of a defense mechanism against wounding pathogens, we examined pILR3::β-GLUCURONIDASE expression and found that Fe deficiency enhances the wound-induced expression of ILR3 in roots and that ILR3 is induced in response to the wounding pathogen, sugarbeet root cyst nematode (Heterodera schachtii). We also examined the expression pattern of genes involved in Fe homeostasis and aliphatic GLS biosynthesis in pye-1, ilr3-2 and pye-1xilr3-2 (pxi) mutants and found that ILR3 and PYE differentially regulate the expression of genes involved these processes under Fe deficiency. We measured GLS levels and sugarbeet root cyst nematode infection rates under varying Fe conditions, and found that long-chain GLS levels are elevated in ilr3-2 and pxi mutants. This increase in long-chain GLS accumulation is correlated with elevated nematode resistance in ilr3-2 and pxi mutants in the absence of Fe. Our findings suggest that ILR3 and PYE function in a regulatory network that controls wounding pathogen response in plant roots by modulating GLS accumulation under iron deficiency. [ABSTRACT FROM AUTHOR]

Porous FeO/carbon microspheres (PFCMs) were successfully fabricated via a facile electrospray method and subsequent heat treatment, using ferrous acetylacetonate, carbon nanotubes (CNTs), Ketjen black (KB), polyvinylpyrrolidone (PVP), and polystyrene (PS) as raw materials. The porous carbon sphere framework decorated with well-dispersed CNTs and KB exhibits excellent electronic conductivity and acts as a good host to confine the FeO nanoparticles. The abundant mesopores in the carbon matrix derived from polymer pyrolysis can effectively accommodate the volume changes of FeO during the charge/discharge process, facilitate electrolyte penetration, and promote fast ion diffusion. Moreover, a thin amorphous carbon layer on the FeO nanoparticle formed during polymer carbonization can further alleviate the mechanical stress associated with volume changes, and preventing aggregation and exfoliation of FeO nanoparticles during cycling. Therefore, as anode materials for lithium-ion batteries, the PFCMs exhibited excellent cycling stability with high specific capacities, and outstanding rate performances. After 130 cycles at a small current density of 0.1 A·g, the reversible capacity of the PFCM electrode is maintained at almost 1,317 mAh·g. High capacities of 746 and 525 mAh·g were still achieved after 300 cycles at the larger currents of 1 and 5 A·g, respectively. The optimized structure design and facile fabrication process provide a promising way for the utilization of energy storage materials, which have high capacities but whose performance is hindered by large volume changes and poor electrical conductivity in lithium or sodium ion batteries. [ABSTRACT FROM AUTHOR]

The lithium-ion batteries show extremely poor cycling performance at low temperature. The main degradation mechanism is not clear. To address the fading mechanism, the cycling degradation of commercial LiFePO/mesocarbon microbead (MCMB) batteries under various charge rate (1/10C, 1/3C, 1/2C, and 1C) at −10 °C is systematically investigated using nondestructive tests combining with post-mortem analysis. The low-temperature charging under high charge rates of 1/3C, 1/2C, and 1C results in severe lithium plating, which leads to extremely serious capacity loss. In contrast, no lithium plating occurred under low charge rate of 1/10C. The lithium plating on the anode surface leads to consumption of active lithium ions and electrolyte, which causes the capacity decay and increases ohmic resistance ( R ) with cycling number under high charge rates. The lithium plating on the anode surface is partially reversible, which brings about the capacity recovery of batteries after 80 cycles at 25 °C. The above results are proved by the followed post-mortem measurements. The evolution of the surface morphologies of MCMB electrodes upon cycling shows that a layer composed of rod-like lithium is formed on the anode surface. [ABSTRACT FROM AUTHOR]

Recently, increasing attention has been paid to magneto-conjugated polymer core-shell nanoparticles (NPs) as theranostic platforms. However, the utilization of surfactants and extra oxidizing agents with potential toxicity in synthesis, the lack of general methods for the controlled synthesis of various kinds of magnetic NP (MNP)@conjugated polymer NPs, and the difficulty of obtaining balanced magneto-optical properties have greatly limited the applications of magneto-conjugated polymers in theranostics. We developed an in situ surface polymerization method free of extra surfactants and oxidizing agents to synthesize MNP@polypyrrole (PPy) NPs with balanced, prominent magneto-optical properties. MNP@PPy NPs with an adjustable size, different shapes, and a controlled shell thickness were obtained using this method. The method was extended to synthesize other MNP-conjugated polymer core-shell NPs, such as MNP@polyaniline and MNP@poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS). We discuss the formation mechanism of the proposed method according to our experimental results. Finally, using the optical and magnetic properties of the obtained MNP@PEDOT:PSS NPs, in vivo multimodal imaging-guided hyperthermia was induced in mice, achieving an excellent tumor-ablation therapeutic effect. Our work is beneficial for extending the application of MNP-conjugated polymer core-shell NPs in the biomedical field. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-021-26190-2, published online 12 October 2021 The original version of this article contained errors in Figure 3a and Figure 3f. In Figure 3a, the activation energies (Ea) were calculated using a log scale instead of a logarithm ln scale. The correct y-axis interval in Figure 3f and the numerical values of the activation energy are now provided in Figure 3a and the main text. [Extracted from the article]

Germanium-tin (GeSn) films with Sn compositions from 5% to 11% were grown on Ge-buffered Si using a reduced pressure chemical vapor deposition system with low-cost SnCl and GeH precursors. Material characterization showed that relaxed GeSn layers with thicknesses ranging from 400 nm to 1 μm were achieved. The strong photoluminescence (PL) intensity and the low defect density indicated very high material quality. In addition, temperature-dependent 10-300 K photoluminescence spectra showed that, due to strain relaxation of the material, the emission wavelength is longer than that of strained GeSn thin film samples ( t < 200 nm) having the same Sn composition. At 300 K, the PL peak at 2520 nm was observed from the sample with a 1- μm-thick GeSn layer and 11% Sn composition. [ABSTRACT FROM AUTHOR]

This paper reports the study of GeSn/GeSn/GeSn single quantum well (SQW) and double quantum wells (DQWs). The quantum well (QW) structures were grown on Ge buffered Si substrates using an industrial standard reduced-pressure chemical vapor deposition system. Pseudomorphically grown structures were observed using x-ray diffraction measurements. Defect-free interfaces between each layer were revealed using cross-sectional transmission electron microscopy. Atomic-scale high-resolution transmission electron microscopy and Fourier transform patterns exhibited the high crystalline quality of QWs. Temperature-dependent photoluminescence (PL) was performed, and the emission peaks attributed to the QW region were identified. The dominant optical transition changed from direct bandgap transition at 300 K to indirect bandgap transition at 10 K. Theoretical calculation showed the type-I band alignment for the QWs. Moreover, the Γ and L valley electron distributions and non-radiative lifetimes were evaluated, which further explained the PL characteristics of the QW samples. [ABSTRACT FROM AUTHOR]