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Abstract The variability of renewable energy within microgrids (MGs) necessitates the smoothing of power fluctuations through the effective scheduling of internal power equipment. Otherwise, significant power variations on the tie‐line connecting the MG to the main power grid could occur. This study introduces an innovative scheduling strategy that utilizes a data‐driven approach, employing a deep reinforcement learning algorithm to achieve this smoothing effect. The strategy prioritizes the scheduling of MG's internal power devices, taking into account the stochastic charging patterns of electric vehicles. The scheduling optimization model is initially described as a Markov decision process with the goal of minimizing power fluctuations on the interconnection lines and operational costs of the MG. Subsequently, after preprocessing the historical operational data of the MG, an enhanced scheduling strategy is developed through a neural network learning process. Finally, the results from four scheduling scenarios demonstrate the significant impact of the proposed strategy. Comparisons of reward curves before and after data preprocessing underscore its importance. In contrast to optimization results from deep deterministic policy gradient, soft actor‐critic, and particle swarm optimization algorithms, the superiority of the deep deterministic policy gradient algorithm with the addition of a priority experience replay mechanism is highlighted.

Abstract Abrupt monsoon onsets/retreats are indispensable targets for climate prediction and future projection, but the origins of their abruptness remain elusive. This study establishes the existence of three climatological Madden-Julian Oscillation (CMJO) episodes contributing to the rapid Australian summer monsoon retreat in mid-March, the South China Sea (or East Asian) summer monsoon onset in mid-May, and the Indian summer monsoon onset in early June. The CMJO displays a dynamically coherent convection-circulation structure resembling its transitionary counterpart, demonstrating its robustness as a convectively coupled circulation system and the tendency of the transient MJOs’ phase-lock to the annual cycle. The CMJO is inactive during the boreal winter due to destructive year-to-year modulations of El Niño-Southern Oscillation. We hypothesize that the interaction between atmospheric internal variability (MJO) and the insolation-forced slow annual cycle generates the sudden monsoon withdrawal/onset during the boreal spring. Understanding the factors determining the timing and location of the MJO’s phase-locking and its variability is vital for monsoon forecasting and climate projection.

Abstract Tianshan Mountains are the headwater regions for the central Asia rivers, providing water resources for ecological protection and economic development in semiarid regions. Due to scarce observations, the hydroclimatic characteristics of the Tianshan Mountains Precipitation (TMP) measured over highland (>1500 m) regions remain to be revealed. Here, we show the TMP belongs to a monsoon-like climate regime, with a distinct annual range and a high ratio of summer-to-yearly rainfall, and exhibits six abrupt changes, dividing the annual cycle into six precipitation sub-seasons. Over the past 60 years, the yearly TMP has significantly increased by 17.3%, with a dramatic increase in winter (135.7%). The TMP displays a significant 40-day climatological intra-seasonal oscillation (CISO) in summer. The TMP CISO’s wet phase results from the confrontation of the eastward propagating mid-tropospheric Balkhash Lake Low and the southward migrating Mongolian High. The sudden changes in the two climatological circulation systems trigger TMP’s changes, shaping the 40-day CISO. Emerging scientific issues are also discussed.

The use of isolation layer structures has been a proven and effective method in reducing the seismic dynamic response of tunnels. It is considered a crucial measure in enhancing the seismic capacity of tunnels. This paper focused on the Xianglushan Tunnel Project and investigated the key factors affecting the glass fiber reinforced concrete (GFRC) isolation layer through shaking table tests. The research analyzed the seismic dynamic response characteristics of the lining under varying fiber content, isolation layer thickness, and seismic intensity. According to the test results, the GFRC isolation layer is more effective in reducing the acceleration and strain response of the lining compared to the rubber isolation layer, indicating a superior isolation effect. The shock absorption effect of the GFRC isolation layer is affected by its fiber content. The best effect is achieved when the isolation layer thickness and lining thickness are in the ratio of 1:1 and the GFRC isolation layer contains 0.9 % glass fiber. The thickness of the GFRC isolation layer has an optimal interval, which is directly related to the glass fiber content. The effectiveness of the GFRC isolation layer in reducing seismic impact decreases as the intensity of the earthquake increases. While the GFRC isolation layer cannot alter the way in which the lining deforms or fails during an earthquake, it can help reduce the seismic dynamic response of critical parts of the lining.

Abstract 2D MoTe2 is regarded as a favorable candidate for semiconductor nanoelectronics integration. Chemical‐vapor‐deposition‐grown MoTe2 usually presents p‐type characteristics. In order to realize basic electronic units like complementary metal‐oxide‐semiconductor (CMOS) inverter, controllable fabrication of p‐ and n‐type transistors at large scale is of vital importance. Here, large‐scale MoTe2 n‐channel field‐effect transistor (n‐FET) arrays are successfully fabricated with seamless coplanar metallic 1T′‐WTe2 contacts to reduce contact resistance. High‐k HfO2 serves as a gate dielectric and its atomic‐layer‐deposition (ALD) process causes an n‐doping effect on the 2H‐MoTe2 channel. The FETs perform typical n‐type characteristics with average electron density and on/off ratio of ≈1.7 × 1013 cm−2 and 2.1 × 104, respectively. Furthermore, large‐scale homogeneous CMOS inverter arrays are fabricated, showing clear logic swing with low power consumption (≈0.4 nW) and high device yield (≈92%). Notably, their voltage transfer characteristics exhibit small hysteresis, and they work well after being kept in air for 16 months, indicating high device stability. The statistical results show that both the n‐FETs and CMOS inverters have high uniformity and reliability in performance. Significantly, this fabrication method is free from transfer processes and compatible with traditional silicon technology. This work paves the way for the application of few‐layer MoTe2 in semiconductor nanoelectronics integration.

Highlights Fabrication, characterizations and photothermal properties of MXenes are systematically described. Photothermal-derived antibacterial performances and mechanisms of MXenes-based materials are summarized and reviewed. Recent advances in the derivative applications relying on antibacterial properties of MXenes-based materials, including in vitro and in vivo sterilization, solar water evaporation and purification, and flexible antibacterial fabrics, are investigated. Abstract The pernicious bacterial proliferation and emergence of super-resistant bacteria have already posed a great threat to public health, which drives researchers to develop antibiotic-free strategies to eradicate these fierce microbes. Although enormous achievements have already been achieved, it remains an arduous challenge to realize efficient sterilization to cut off the drug resistance generation. Recently, photothermal therapy (PTT) has emerged as a promising solution to efficiently damage the integrity of pathogenic bacteria based on hyperthermia beyond their tolerance. Until now, numerous photothermal agents have been studied for antimicrobial PTT. Among them, MXenes (a type of two-dimensional transition metal carbides or nitrides) are extensively investigated as one of the most promising candidates due to their high aspect ratio, atomic-thin thickness, excellent photothermal performance, low cytotoxicity, and ultrahigh dispersibility in aqueous systems. Besides, the enormous application scenarios using their antibacterial properties can be tailored via elaborated designs of MXenes-based materials. In this review, the synthetic approaches and textural properties of MXenes have been systematically presented first, and then the photothermal properties and sterilization mechanisms using MXenes-based materials are documented. Subsequently, recent progress in diverse fields making use of the photothermal and antibacterial performances of MXenes-based materials are well summarized to reveal the potential applications of these materials for various purposes, including in vitro and in vivo sterilization, solar water evaporation and purification, and flexible antibacterial fabrics. Last but not least, the current challenges and future perspectives are discussed to provide theoretical guidance for the fabrication of efficient antimicrobial systems using MXenes.

Abstract East Asia will face a skewed monsoon cycle with soaring flood, drought, and weather whiplash risks in a warming climate. In our objective eight-intraseasonal-monsoon-stage framework, we uncover a ‘dry-get-wetter’ paradigm in East Asia, contesting the fallen ‘rich-get-richer’ common belief. On timing, the Mid-summer and Fall periods are stretching at the expense of three delayed, shortened, and weakened winter stages, especially near the end of the twenty-first century. On threats, entire East Asia will experience up to 14–20 more heavy precipitation days during the rainy Spring to Mid-summer stages. Specifically, the Yangtze basin will suffer from an earlier pluvial period with escalating flood risks. Moreover, societal security and ecosystem resilience in the Huai-Yellow basin, South Japan, and the Korean Peninsula will be challenged by more frequent weather whiplash. Under the monsoon-stage framework, a complete moisture budget decomposition sheds light on the causes of a slower precipitation scaling and the ‘dry-get-wetter’ paradigm.

Two-dimensional magnetic semiconductors hold promise for spin- and valleytronic applications. Here, the authors report the realization of light helicity detectors based on graphene/CrI3 van der Waals heterostructures, exhibiting a photocurrent behaviour determined by the magnetic state of CrI3.

ObjectiveTo analyze the related factors of the postpartum thyroid function in women with overt hypothyroidism (OH)/subclinical hypothyroidism (SCH) and explore the effects of vitamin D categories.MethodsThyroid hormones, thyroid autoantibody, and serum 25OHD levels were continuously recorded from the first trimester of pregnancy (T1) to the 12th postpartum month. Logistic regression analysis and Cox regression analysis were used to screen the related factors of postpartum thyroid function, and the Latent Class Growth Model was performed to analyze the trajectory characteristics of serum 25OHD levels.ResultsTotally, 252 pregnant women with OH/SCH were enrolled in the study. In the 12th month postpartum, 36.5% of the patients improved thyroid function, 37.3% continued hypothyroidism, and 26.2% developed thyroid dysfunction. Vitamin D sufficiency, positive TPOAb, and positive TgAb in T1 were independent prognostic factors of postpartum thyroid function. Vitamin D sufficiency in T1 was illustrated as an independent factor of the improved postpartum thyroid function, but the protective effect for the developed postpartum thyroid dysfunction was only confirmed in TPOAb-positive patients. Cox regression analysis further confirmed the effects of vitamin D categories. Notably, the high-level 25OHD trajectory during pregnancy and postpartum could predict improved postpartum thyroid function and decrease the risk of developed postpartum thyroid dysfunction.ConclusionAppropriate vitamin D nutrition during pregnancy and postpartum may be beneficial to postpartum thyroid function.

PurposeThis study aimed to investigate the changes in the functional connectivity between the bilateral thalamus and the whole-brain in patients with severe traumatic brain injury (sTBI) patients suffering from disorders of consciousness (DOC) and to explore their potential prognostic representation capacity.MethodsThe sTBI patients suffering from DOC and healthy controls underwent functional magnetic resonance imaging. We defined patients with the Extended Glasgow Outcome Score (GOS-E) ≥ 3 as the wake group and GOS-E = 2 as the coma group. The differences in functional connectivity between sTBI and healthy controls and between wake and coma groups were compared. Based on the brain regions with altered functional connectivity between wake and coma groups, they were divided into 26 regions of interest. Based on the Z-values of regions of interest, the receiver operating characteristic analysis was conducted to classify the prognosis of patients.ResultsA total of 28 patients and 15 healthy controls were finally included. Patients who had DOC indicated a significant disruption of functional connectivity between the bilateral thalamus and the whole-brain (FDR corrected, P < 0.0007). The functional connectivity strength (bilateral thalamus to whole-brain) was significantly different between coma patients who went on to wake and those who were eventually non-awake at 6 months after sTBI (Alphasim corrected, P < 0.05). Furthermore, the 26 regions of interest had a similar or even better prognostic distinction ability than the admission Glasgow coma score.ConclusionThe thalamus-based system of consciousness of sTBI patients suffering from DOC is disrupted. There are differences in the thalamus-to-whole-brain network between wake and coma groups and these differences have potential prognostic characterization capability.

The use of the heavy hammer compaction method can enhance the bearing characteristics of underwater rubble-mound foundations. This is crucial to ensure the safety and stability of port and coastal engineering projects. In the present work, a combination of image-recognition technology, 3D laser scanning technology, a discrete element numerical simulation, and a field test was first utilized to establish riprap particles and reconstruct a discrete element numerical model of a rubble-mound foundation, and then the effects of various influencing factors on the bearing characteristics of the rubble-mound foundation were studied. The main conclusions are as follows. (1) The load–settlement curve of the rubble-mound foundation can be divided into three stages: rapid growth stage, slow growth stage, and failure stage. (2) The ultimate bearing capacity of the rubble-mound foundation is positively correlated with the vibration time and vibration amplitude. The riprap particle size and the foundation thickness have negligible effects on the ultimate bearing capacity of the rubble-mound foundation. (3) When adjusting the vibration time, vibration amplitude, and foundation thickness, the settlement value of the rubble-mound foundation tends to increase as the compactness increases. On the other hand, the effects of factors such as the riprap particle size, riprap particle gradation, and vibration frequency on the compactness and settlement value of the rubble-mound foundation are less significant.

BackgroundVariations in the gut microbiota may affect the metabolism, inflammation and immune response of the host. Microbiota dysbiosis has been extensively investigated in neurological disorders and diseases of the central nervous system (CNS). However, the alterations of the gut microbiota in patients suffering from brain tumors and the associations of the gut microbiota with these diseases remain unknown. Herein, we investigate the alterations of the gut microbiota community in patients with brain tumors and the associations between the two and further explore microbial markers used for the diagnosis of brain tumors.MethodsIn our study, we recruited 158 participants, consisting of 101 brain tumor patients (65 benign and 36 malignant cases) and 57 age- and sex-matched healthy controls (HCs). We characterized the gut microbial community by using 16S rRNA gene amplicon sequencing and investigated its correlations with clinical features.ResultsThe results showed remarkably less microbial ecosystem richness and evenness in patients with brain tumors than in HCs. The gut microbiota community structure underwent profound changes in the brain tumor group, including an increase in the abundances of pathogenic bacteria, such as Fusobacteriota and Proteobacteria and a reduction in the abundances of probiotic bacteria, such as Bifidobacterium or Lachnospira. Moreover, our study indicated more significant correlations and clustering of pathogens in the malignant brain tumor group. Furthermore, a biomarker panel was used to discriminate the brain tumor patients from the healthy controls (AUC: 0.77). Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation revealed an accumulation of harmful metabolites and disorders of the basic physiological pathways in the brain tumor group.ConclusionsOur study revealed that brain tumor patients may possess divergent host-microbe interactions from those of healthy controls, especially in malignant brain tumor patients. In addition, the intestinal flora may be involved in immune responses and metabolism in the microenvironment of brain tumors. All evidence, including the biomarker panel, suggests that the intestinal flora may be a useful diagnostic and predictive tool and an important preventive target for brain tumors.

Abstract Rain belts in East Asia frequently pose threats to human societies and natural systems. Advances in a skillful forecast on heavy precipitation require a deeper understanding of the preconditioned environments and the hydrologic cycle. Here, we disentangle 15 dominant moisture channels along four corridors reaching the Somali Jet, South Asia, Bay of Bengal, and Pacific basin for the warm-season rain belts. Among them, the Somali and South Asian channels were underappreciated in the literature. The results also highlight the importance of terrestrial moisture sources, and the close relationship between the moisture pathways and rain belts’ characteristics. Back-tracing the weather within a 2-week lead time reveals the pre-existing weather systems and circumglobal wave trains, that govern the moisture channels. Findings from this work develop a better understanding of East Asian rain belts’ water cycle, and may offer insights into model evaluation and heavy rainfall prediction at a longer lead time.

The perovskite microlaser is a competitive candidate of light source for optical communication and integrated photonic circuits. Understanding the fundamental mechanism of lasing is crucial for the upcoming devices. The ultrafast establishment of lasing modes within a 2D perovskite microplate cavity at room temperature is investigated. The transient red shift of lasing modes can be found. Analysis based on electron–hole plasma (EHP) and a dynamic Drude‐like model are carried out with simulations on the transient dielectric response and the mode shift. In addition, the integrated lasing gain profile have a red shift at high excitation intensity, which is explained with EHP‐induced bandgap renormalization. The conflict between the experimental phenomena and the exciton–polariton theory confirms that under intense excitation, the exciton–polariton is ruled out for the origin of lasing. These results provide a direct understanding of the lasing evolving in a 2D perovskite microcavity. Suppressing the EHP‐related transient shift of cavity modes will advance the lasing applications.

Summary: Two-dimensional (2D) semi-conductive transition metal dichalcogenides (TMDCs) have shown advantages for logic application. Complementary metal-oxide-semiconductor (CMOS) inverter is an important component in integrated circuits in view of low power consumption. So far, the performance of the reported TMDCs-based CMOS inverters is not satisfactory. Besides, most of the inverters were made of mechanically exfoliated materials, which hinders their reproducible production and large-scale integration in practical application. In this study, we demonstrate a practical approach to fabricate CMOS inverter arrays using large-area p-MoTe2 and n-MoS2, which are grown via chemical vapor deposition method. The current characteristics of the channel materials are balanced by atomic layer depositing Al2O3. Complete logic swing and clear dynamic switching behavior are observed in the inverters. Especially, ultra-low power consumption of ∼0.37 nW is achieved. Our work paves the way for the application of 2D TMDCs materials in large-scale low-power-consumption logic circuits.

Cancellous bone plays an indispensable role in the skeletal system due to its various functions and high porosity. In this work, chitosan and hydroxyapatite nanowires (CS@HAP NWs) hybrid nanostructured scaffolds with suitable mechanical properties, high porosity and a fine porous structure were prepared to simulate the 3-dimensional structure of cancellous bone. The 3D-hybrid scaffolds promote cell adhesion and the migration of human adipose-derived stem cells (hADSCs) inside the scaffolds. The cavities in the scaffolds provide space for the hADSCs proliferation and differentiation. Moreover, the various contents of HAP and the induced mechanical property changes regulate the differentiation of hADSCs toward osteoblasts. Overall, cellular fate regulation of hADSCs via rationally engineered HAP-based hybrid scaffolds is a facile and effective approach for bone tissue engineering.

Triple-negative breast cancer is an aggressive form of the disease. Here, the authors identify EGFL9 as a mediator of metastasis in TNBC through interactions with cMET.

In this work, a novel amphoteric copolymer named Poly(sodium p-styrenesulfonate–co-acrylic acid-co-diallyldimethylammonium chloride) (P(SS-co-AA-co-DMDAAC)) was synthesized via free radical polymerization. Afterwards, P(SS-co-AA-co-DMDAAC) was explored for use as a dispersant in coal water slurry (CWS) preparation. The structure of P(SS-co-AA-co-DMDAAC) was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The synthetic conditions were optimized as the feed ratio of AA to SS was 1 : 1 (for Yulin coal) or 1.5 : 1 (for Yili coal), and DMDAAC dosage was 4.0 wt% (for Yulin coal) and 6.0 wt% (for Yili coal) toward total monomers. The performances of P(SS-co-AA-co-DMDAAC) as a dispersant for CWS were evaluated by various technologies, such as apparent viscosity, zeta potential, static stability and contact angle measurements. The results revealed that the optimized dosage of P(SS-co-AA-co-DMDAAC) in CWS preparation was 0.3 and 0.4 wt% for Yulin coal and Yili coal respectively. In this optimum condition, CWS prepared using P(SS-co-AA-co-DMDAAC) as dispersant showed a typical shear thinning behaviour and excellent stability, which are desired in industries. The rheological models also confirmed the pseudo-plastic characteristics of CWS. Finally, compared with the widely used anionic dispersant naphthalene sulphonate formaldehyde condensate (NSF) and poly(sodium p-styrenesulfonate) (PSS), P(SS-co-AA-co-DMDAAC) developed in this work exhibited better slurry making performance. The introduction of cationic functional groups promoted the adsorption of the dispersant, which further enhanced the electrostatic repulsion and steric hindrance among coal particles. Accordingly, the viscosity of CWS decreased and static stability enhanced.

Two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides (TMDCs), are highly appealing in the fields of electronics, optoelectronics, energy, etc. Graphene, with high conductivity and high carrier mobility, is an excellent candidate for transparent electrodes. TMDCs have remarkably strong light absorption in the range of visible to infrared wavelength. High-performance photodetectors are expected to achieve through the combination of graphene and TMDCs. Nowadays, near-infrared (NIR) photodetectors play significant roles in many areas. MoTe2 with bandgap energy of about 1.0 eV in its bulk form is a promising material for cost-saving NIR photodetectors. Thus far, only a few of the reported studies on NIR photodetectors built on MoTe2/graphene heterostructures have achieved high responsivity and short response time simultaneously in one device. In this study, we fabricate graphene–MoTe2–graphene vertical van der Waals heterostructure devices through chemical vapor deposition (CVD) growth, wet transfer method, and dry etching technique. Under 1064 nm laser illumination, we acquire responsivity of as high as 635 A/W and a response time of as short as 19 μs from the as-fabricated device. Moreover, we acquire higher responsivity of 1752 A/W and a shorter response time of 16 μs from the Al2O3-encapsulated device. Our research drives the application of 2D materials in the NIR wavelength range.