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HighlightsThis review summarizes applications and developments of MXenes in solar cells by far. The issues needing to be addressed for performance improvement of the related solar cells are discussed.Suggestions are given for pushing exploration of MXenes’ application in solar cells.Application of two-dimensional MXene materials in photovoltaics has attracted increasing attention since the first report in 2018 due to their metallic electrical conductivity, high carrier mobility, excellent transparency, tunable work function and superior mechanical property. In this review, all developments and applications of the Ti3C2Tx MXene (here, it is noteworthy that there are still no reports on other MXenes’ application in photovoltaics by far) as additive, electrode and hole/electron transport layer in solar cells are detailedly summarized, and meanwhile, the problems existing in the related studies are also discussed. In view of these problems, some suggestions are given for pushing exploration of the MXenes’ application in solar cells. It is believed that this review can provide a comprehensive and deep understanding into the research status and, moreover, helps widen a new situation for the study of MXenes in photovoltaics.

The Shunbei ultra-deep carbonate strike-slip fault-controlled reservoir in Tarim Basin is rich in reserves. The strike-slip faults and the natural structural fractures are the main storage space and flow channels of hydrocarbon resources. Therefore, studying the natural fracture development characteristics in this kind of reservoir is of great significance. The lithology of the Middle and Lower Ordovician strata in the Shunbei area is limestone and dolomite, including packstone, wackestone, grainstone, boundstone, lime mudstone, silicified limestone and silty-fine crystalline dolomite, medium-coarse crystalline dolomite. Based on the statistics of fracture density and brittleness index of core samples, it is found that in limestone, lime mudstone has the highest brittleness index, while boundstone has the lowest; in dolomite, the brittleness index of medium-coarse crystalline dolomite is higher than that of silty-fine crystalline dolomite. The natural structural fracture density has an obvious positive correlation with the rock brittleness index. The brittleness index of dolomite is generally higher than that of limestone. When the brittleness index is the same, dolomite has superior porosity and permeability, whereas limestone has a stronger capacity to fracture. Those kinds of highly brittle layers in carbonate reservoirs are more likely to be geological sweet spots in the Shunbei area.

Background Gestational diabetes mellitus (GDM), a common endocrine disorder with rising prevalence in pregnancy, has been reported to be associated with alteration of gut microbiota in recent years. However, the role of gut microbiome in GDM physiopathology remains unclear. This pilot study aims to characterize the alteration of gut microbiota in GDM on species-level resolution and evaluate the relationship with occurrence of GDM. Methods An analysis based on 16S rRNA microarray was performed on fecal samples obtained from 30 women with GDM and 28 healthy pregnant women. Results We found 54 and 141 differentially abundant taxa between GDM and control group at the genus and the species level respectively. Among GDM patients, Peptostreptococcus anaerobius was inversely correlated with fasting glucose while certain species (e.g., Aureimonas altamirensis , Kosakonia cowanii ) were positively correlated with fasting glucose. Conclusions This study suggests that there are large amounts of differentially abundant taxa between GDM and control group at the genus and the species level. Some of these taxa were correlated with blood glucose level and might be used as biomarkers for diagnoses and therapeutic targets for probiotics or synbiotics.

Background To investigate the epidemiological, clinical characteristics and outcomes of diabetes in pregnancy (DIP). Methods This single-center, retrospective study included 16,974 pregnant women hospitalized during 2018–2019. Among them, 2860 DIP patients were grouped according to diabetes type, glycemic status, and insulin use. Multivariate logistic regression analysis was conducted. Results The incidence of DIP [17.10%; pregestational diabetes mellitus (PGDM), 2.00% (type I, 0.08%; type 2, 1.92%); gestational diabetes mellitus (GDM), 14.85% (GDM A1, 13.58%; GDM A2, 1.27%)] increased annually. Premature birth, congenital anomalies, large for gestational age (LGA), neonatal asphyxia, neonatal intensive care unit transfer, hypertension, and puerperal infection were more common in DIP than in healthy pregnancies. The most common comorbidities/complications were hypertension, thyroid dysfunction, cervical incompetence, intrahepatic cholestasis, premature membrane rupture, oligo/polyhydramnios, and fetal distress. GDM incidence at ages ≥35 and ≥ 45 years was 1.91 and 3.26 times that at age < 35 years, respectively. If only women with high-risk factors were screened, 34.8% GDM cases would be missed. The proportion of insulin use was 14.06% (PGDM, 55%; GDM, 8.53%). Mean gestational age at peak insulin dose in DIP was 32.87 ± 5.46 weeks. Peak insulin doses in PGDM and GDM were 3.67 and 2 times the initial doses, respectively. The risks of LGA, premature birth, cesarean section, and neonatal hypoglycemia in PGDM were 1.845, 1.533, 1.797, and 1.368 times of those in GDM, respectively. The risks of premature birth and neonatal hypoglycemia in women with poor glycemic control were 1.504 and 1.558 times of those in women with good control, respectively. Conclusions The incidence of adverse outcomes in DIP is high.

The durability of permeable pavement needs to be further studied by accelerated pavement testing (APT). Full-scale APT facilities are commonly associated with a very high initial investment and operational costs. A piece of small-scale accelerated testing equipment, the model mobile load simulator (MMLS), was used to investigate and evaluate the mechanical properties of three types of permeable asphalt pavements, including a 4 cm porous asphalt layer with cement-treated permeable base (4PA-CTPB), 7 cm porous asphalt layer with cement-treated permeable base (7PA-CTPB), and 7 cm porous asphalt layer with cement-treated base (7PA-CTB). Under different conditions of subgrade soil, transverse and longitudinal strains at the bottom of the porous asphalt layer and average rut depth and temperature data were collected. The results indicated that 4PA-CTPB produced the maximum average rut depth but minimum resilient tensile strain. The transverse resilient tensile strain of 7PA-CTPB was significantly higher than the other two structures under both wet and dry conditions. The transverse resilient tensile strain significantly increased with increasing loading cycles with a decreasing rate, which could be affected by both load and temperature. MMLS could be used to explore and evaluate the mechanical properties of permeable asphalt pavement. From the data under dry and wet conditions, it may be better to increase the strength of the subgrade, where a suitable hydraulic conductivity coefficient should be considered.

Volatile organic compounds (VOCs) play an important role in the biological activities of the medicinal Zingiberaceae species. In commercial preparations of VOCs from Kaempferia parviflora rhizomes, its leaves are wasted as by-products. The foliage could be an alternative source to rhizome, but its VOCs composition has not been explored previously. In this study, the VOCs in the leaves and rhizomes of K. parviflora plants grown in a growth room and in the field were analyzed using the headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography and time-of-flight mass spectrometry (GC-TOF-MS). The results showed a total of 75 and 78 VOCs identified from the leaves and rhizomes, respectively, of plants grown in the growth room. In the field samples, 96 VOCs were detected from the leaves and 98 from the rhizomes. These numbers are higher compared to the previous reports, which can be attributed to the analytical techniques used. It was also observed that monoterpenes were dominant in leaves, whereas sesquiterpenes were more abundant in rhizomes. Principal component analysis (PCA) revealed significantly higher abundance and diversity of VOCs in plants grown in the field than in the growth room. A high level of similarity of identified VOCs between the two tissues was also observed, as they shared 68 and 94 VOCs in the growth room and field samples, respectively. The difference lies in the relative abundance of VOCs, as most of them are abundant in rhizomes. Overall, the current study showed that the leaves of K. parviflora, grown in any growth conditions, can be further utilized as an alternative source of VOCs for rhizomes.

Background Risk prediction models can identify individuals at high risk of chronic liver disease (CLD), but there is limited evidence on the performance of various models in diverse populations. We aimed to systematically review CLD prediction models, meta-analyze their performance, and externally validate them in 0.5 million Chinese adults in the China Kadoorie Biobank (CKB). Methods Models were identified through a systematic review and categorized by the target population and outcomes (hepatocellular carcinoma [HCC] and CLD). The performance of models to predict 10-year risk of CLD was assessed by discrimination (C-index) and calibration (observed vs predicted probabilies). Results The systematic review identified 57 articles and 114 models (28.4% undergone external validation), including 13 eligible for validation in CKB. Models with high discrimination (C-index ≥ 0.70) in CKB were as follows: (1) general population: Li-2018 and Wen 1–2012 for HCC, CLivD score (non-lab and lab) and dAAR for CLD; (2) hepatitis B virus (HBV) infected individuals: Cao-2021 for HCC and CAP-B for CLD. In CKB, all models tended to overestimate the risk (O:E ratio 0.55–0.94). In meta-analysis, we further identified models with high discrimination: (1) general population (C-index ≥ 0.70): Sinn-2020, Wen 2–2012, and Wen 3–2012 for HCC, and FIB-4 and Forns for CLD; (2) HBV infected individuals (C-index ≥ 0.80): RWS-HCC and REACH-B IIa for HCC and GAG-HCC for HCC and CLD. Conclusions Several models showed good discrimination and calibration in external validation, indicating their potential feasibility for risk stratification in population-based screening programs for CLD in Chinese adults.

The exploration of deeply buried hydrocarbon is still a challenge for the petroleum geology. The Shunbei area is a newly discovered oil fields, located in the center of the Tarim Basin. The oil is mainly yielded from the Middle–Lower Ordovician carbonate reservoirs with depth>7000 m in the Shunbei No. 1 and No. 5 fault zones. Calcite cements filled in vugs (v-calcite) and fractures (f-calcite) are identified in limestones and dolostones of the carbonate reservoirs. F-calcites in the Shunbei No. 1 fault zone trap secondary inclusions in trails, which comprise liquid-dominated biphase aqueous inclusions, liquid-dominated biphase oil inclusions, and/or oil-bearing triphase inclusions. F-calcite and v-calcite in the No. 5 fault zone trap secondary inclusions in trails, which consist of liquid-only monophase aqueous inclusions, liquid-dominated biphase aqueous inclusions, liquid-dominated biphase oil inclusions, liquid-only monophase oil inclusions, and/or oil-bearing triphase inclusions. The ranges of the homogenization temperature (Th) and ice-melting temperature (Tm−ice) in the Shunbei No. 1 fault zone are, respectively, 130–150°C and -2.1–-1.5°C. The coexistence of liquid-only and liquid-dominated aqueous inclusions in the Shunbei No. 5 fault zone indicates that the aqueous inclusions are trapped at low temperatures. The aqueous inclusions in the Shunbei No. 5 fault zone show a range from -0.4 to -0.2°C in Tm−ice which is very close to the meteoric fluid. In the context of the burial-thermal history and the Cambrian source rock evolution, the charging process of hydrocarbon in the Shunbei No. 1 and No. 5 fault zones corresponds to the Silurian and Middle Ordovician, respectively. Results of fluid inclusions indicate a tightly coupling relationship between the hydrocarbon charging process and fault system evolution in the Shunbei area. This study reveals the application of fluid inclusion under the systemically petrographic constraints to decipher the charging history of hydrocarbon, especially for the deeply buried reservoirs.

Lithium niobate on insulator (LNOI) has been demonstrated as a promising platform for photonic integrated circuits (PICs), thanks to its excellent properties such as strong electro‐optic effect, low material loss, and wide transparency window. Herein, a monolithic PIC for high‐speed data communication application on a lithium‐niobate‐etchless platform with silicon nitride (Si3N4) as a loading material is proposed and demonstrated. The fabricated PIC consists of four racetrack resonator modulators and a pair of four‐channel mode (de)multiplexers, which shows high data modulation rate of 70 Gbps for single channel and the total data throughput reaches up to 280 Gbps. To the best of knowledge, this is the first demonstration of PIC consisting of high‐speed electro‐optical modulators and (de)multiplexers with such high data capacity on Si3N4‐LNOI hybrid platform, which opens up new avenues for achieving large‐scale monolithic integration on LNOI platform in future. Herein, the authors propose and demonstrate a monolithic photonic integrated circuit for high‐speed data communication based on silicon nitride and lithium niobate on an insulator hybrid platform. By combing the modulators with the four‐channel mode (de)multiplexers (MMUXs), the application for on‐chip high‐speed data communication with the 280 Gbps total data throughput has been verified.

Background The current study aimed to investigate whether serum RBP levels can be a key predictor of peripartum depression (PPD). Methods This was a prospective cohort study, conducted at a general teaching hospital in South China. Research participants were evaluated at three time points: the third trimester of pregnancy (T1), after delivery at week one (T2), and after delivery week six (T3) using a set of self-reported questionnaires and blood sample assays. Results A total of 156 subjects were included for data analysis. The prevalence of anxiety symptoms ranged from 32.69% to 36.53%. The prevalence of PPD was also high and ranged from 27.56% to 35.89%. In the third trimester, significant predictors of depressive symptoms include serum retinol-binding protein (RBP) concentrations and estradiol levels ( P  = 0.008 and 0.033, respectively). At one week after delivery, serum concentrations of RBP at T2 were still significant predictors of depressive symptoms ( P  = 0.020, and serum estradiol concentrations at T1 were a significant predictor ( P  = 0.010). The most stable predictor of depressive symptoms at T3 was anxiety symptoms, especially at T3 time point ( P  < 0.001). Serum RBP concentrations at T1 and T2 were still significant predictors of depressive symptoms at T3. Conclusion A high prevalence of anxiety and depressive symptoms tended to persist in Chinese women during the peripartum period. This study, which found the potential contribution of RBP to the occurrence of PPD, requires that large sample studies be conducted in future with a longer-term follow-up period, in order to confirm its results.