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Summary: Ultraviolet (UV) radiation influences development and genome stability in organisms; however, its impact on meiosis, a special cell division essential for the delivery of genetic information across generations in eukaryotes, has not yet been elucidated.In this study, by performing cytogenetic studies, we reported that UV radiation does not damage meiotic chromosome integrity but attenuates centromere‐mediated chromosome stability and induces unreduced gametes in Arabidopsis thaliana.We showed that functional centromere‐specific histone 3 (CENH3) is required for obligate crossover formation and plays a role in the protection of sister chromatid cohesion under UV stress. Moreover, we found that UV specifically alters the orientation and organization of spindles and phragmoplasts at meiosis II, resulting in meiotic restitution and unreduced gametes. We determined that UV‐induced meiotic restitution does not rely on the UV Resistance Locus8‐mediated UV perception and the Tapetal Development and Function1‐ and Aborted Microspores‐dependent tapetum development, but possibly occurs via altered JASON function and downregulated Parallel Spindle1.This study provides evidence that UV radiation influences meiotic genome stability and gametophytic ploidy consistency in flowering plants. [ABSTRACT FROM AUTHOR]

Intravoxel incoherent motion (IVIM) modeling is a widely used double‐exponential model for describing diffusion‐weighted imaging (DWI) signal, with a slow component related to pure molecular diffusion and a fast component associated with microcirculatory perfusion, which compensates for the limitations of traditional DWI. IVIM is a noninvasive technique for obtaining liver pathological information and characterizing liver lesions, and has potential applications in the initial diagnosis and treatment monitoring of liver diseases. Recent studies have demonstrated that IVIM‐derived parameters are useful for evaluating liver lesions, including nonalcoholic fatty liver disease (NAFLD), liver fibrosis and liver tumors. However, the results are not stable. Therefore, it is necessary to summarize the current applications of IVIM in liver disease research, identify existing shortcomings, and point out the future development direction. In this review, we searched for studies related to hepatic IVIM‐DWI applications over the past two decades in the PubMed database. We first introduce the fundamental principles and influential factors of IVIM, and then discuss its application in NAFLD, liver fibrosis, and focal hepatic lesions. It has been found that IVIM is still unstable in ensuring the robustness and reproducibility of measurements in the assessment of liver fibrosis grade and liver tumors differentiation, due to inconsistent and substantial overlap in the range of IVIM‐derived parameters for different fibrotic stages. In the end, the future direction of IVIM‐DWI in the assessment of liver diseases is discussed, emphasizing the need for further research on the stability of IVIM‐derived parameters, particularly perfusion‐related parameters, in order to promote the clinical practice of IVIM‐DWI. Level of Evidence: 5 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

Laterally epitaxial two‐dimensional (2D) transition metal dichalcogenides (TMDs) heterojunctions are of considerable interest in recent years due to atomically sharp interfaces and tunable band alignment, which have potential applications in novel functional electronics and optoelectronics. However, the studies of 2D lateral heterostructures have mainly focused on the synthesis methods and pristine performance of the fabricated heterojunctions. Herein, the controllable photocurrent generation and enhanced performances of the lateral bilayer (LBL) MoS2–WS2 heterojunctions are reported. A tunable and abrupt built‐in field forms at the interface, and the gate‐tunable rectifying behavior and photovoltaic effect are realized. It is demonstrated that the generation of the photocurrent in the device can be highly controlled to realize ultrahigh responsivity of 1.06 × 104 A W−1 and detectivity of 1.14 × 1013 Jones at a 638 nm incident light. The lateral TMDs heterostructures are expected to constitute the ultimate functional elements of novel electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is typically associated with iron (Fe) hydroxides in paddy soils. Our study investigated the impact of different fertilization treatments on the availability of P regulated by Fe redox transformation in a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system in the mid‐low reaches of the Yangtze River. Five fertilization treatments were examined: control (CK), chemical fertilizer (CF), 35% CF (P) plus pig manure compost (CFM), 100% CF (P) plus straw (CFS), and 35% CF (P) plus pig manure compost and straw (CFMS). Nine‐year rice–wheat rotations increased the oxalate‐extractable poorly crystalline Fe hydroxides (i.e., Feo) by 33%–87% compared with the initial soil, while fertilization further accelerated this process. Compost application increased the proportion of labile P by 75%–108% and decreased the proportion of non‐labile P by 14%–22% compared with the single chemical fertilization treatment. Furthermore, organic fertilization increased the mass proportions of macroaggregates and macroaggregate‐associated labile P. The Feo was positively correlated with the content of labile P but negatively correlated with the proportion of non‐labile P. Moreover, the reductive dissolution of Fe hydroxides was accompanied by the transformation of P from NaOH‐extractable to NaHCO3‐ and H2O‐extractable phases. These results indicate that seasonal alternation of drying and wetting can progressively drive the redox transformation of Fe hydroxides and promote the formation of Feo, thereby affecting the availability of P. Therefore, we suggested that P fertilizer should be reduced in the rice season due to the reduction of Fe hydroxides, particularly in the compost‐amended soils in the temperate rice–wheat cropping system. Core Ideas: Fertilization accelerated the poorly crystalline iron hydroxide formation.Organic fertilization enhanced the availability of phosphorus.Poorly crystalline iron hydroxide formation contributed to the increase in phosphorus availability. [ABSTRACT FROM AUTHOR]

Grain boundary cracks in flexible perovskite films can be repaired by filling with self‐repairing polymers during the preparation and wearable operation. However, the self‐repairing polymers are commonly active through external heating or humidification treatments, which cannot match with the human body's temperature tolerance of wearable devices. Herein, a body temperature‐responsive shape memory polyurethane (SMPU) is demonstrated to achieve the real‐time mechanical self‐repairing of grain boundary cracks (~37°C). Furthermore, the strong intermolecular interaction between SMPU and the uncoordinated Pb2+ and I−, can reduce the trap density in perovskite films. The blade‐coated device achieves a power conversion efficiency (PCE) of 21.33%, which is among the best reported flexible perovskite solar cells (PSCs; 0.10 cm2). Importantly, the device with SMPU can recover more than 80% of the PCE after 6000 cycles (bending radius: 8 mm). Finally, the flexible PSCs are used for wearable solar power supply of a smartphone, which show great potential for self‐repairing wearable electronics. [ABSTRACT FROM AUTHOR]

Inorganic cesium lead iodide perovskite CsPbI3 is attracting great attention as a light absorber for single or multi‐junction photovoltaics due to its outstanding thermal stability and proper band gap. However, the device performance of CsPbI3‐based perovskite solar cells (PSCs) is limited by the unsatisfactory crystal quality and thus severe non‐radiative recombination. Here, vacuum‐assisted thermal annealing (VATA) is demonstrated as an effective approach for controlling the morphology and crystallinity of the CsPbI3 perovskite films formed from the precursors of PbI2, CsI, and dimethylammonium iodide (DMAI). By this method, a large‐area and high‐quality CsPbI3 film is obtained, exhibiting a much reduced trap‐state density with prolonged charge lifetime. Consequently, the solar cell efficiency is raised from 17.26 to 20.06 %, along with enhanced stability. The VATA would be an effective approach for fabricating high‐performance thin‐film CsPbI3 perovskite optoelectronics. [ABSTRACT FROM AUTHOR]

Objectives: This study was conducted to evaluate the effect of adding riboflavin to boar sperm freezing extender on the challenge of cryopreservation. Methods: Different concentrations (0, 5, 10, 15, 20 or 25 μM) of riboflavin were added to the freezing extender. Spermatozoa motility, membrane integrity, acrosomal integrity, mitochondrial membrane potential and enzyme activities were analysed once 10 min after thawing. Q‐PCR was used to detect the mRNA expression of Caspase3, Bcl‐2 and Bax. Results: The results showed that the addition of 10 μM riboflavin to boar sperm freezing extender significantly increased the frozen‐thawed sperm progressive motility compared with the control group (p < 0.05). Activities of superoxide dismutase, glutathione peroxidase and catalase improved after adding riboflavin to the extender (p < 0.05). During freezing‐thawing, the boar sperm mitochondrial membrane potential, acrosomal integrity, plasma membrane and DNA at 10 μM in the riboflavin group increased by 6.6%, 9.6%, 5.49% and 5.62% (p < 0.05), respectively, compared with the control group. The addition of 10 μM riboflavin to the extender significantly decreased the malondialdehyde (p < 0.05) content, whereas it increased the ATP content (p < 0.05) of boar sperm during freezing‐thawing. Furthermore, the expression of Caspase‐3 and Bax (p < 0.05) were significantly lower, whereas the expression of BCL‐2 (p < 0.05) was greater than the control group when adding 10 μM riboflavin to the extender. Conclusions: Riboflavin showed cryoprotective capacity to the freezing extender used for boar sperm during the process of freezing‐thawing, and the optimal concentration of riboflavin for the frozen extender was 10 μM. [ABSTRACT FROM AUTHOR]

The objectives of this study were to investigate the relationship between the in vitro ruminal ammonia nitrogen (NH3‐N) concentration and the Cornell Net Carbohydrate and Protein System (CNCPS) N‐fractions of feeds for cattle and further compare the performance of developing multiple linear regression (MLR) and artificial neural network (ANN) models in estimating the NH3‐N concentration in rumen fermentation. Two data sets were established, of which the training data set containing forty‐five rations for cattle with concentrate/roughage ratios of 50:50, 40:60, 30:70, 20:80 and 10:90 used for developing models and the test data set containing ten other rations with the same concentrate/roughage ratios with the training data set were used for validating of models. The NH3‐N concentrations of feed samples were measured using an in vitro incubation technique. The CNCPS N‐fractions (g), for example PB1 (rapidly degraded true protein), PB2 (neutral detergent soluble nitrogen), PB3 (acid detergent soluble nitrogen) of rations, were calculated based on chemical analysis. Statistical analysis indicated that the NH3‐N concentration (mg) was significantly correlated with the CNCPS N‐fractions (g) PB1, PB2 and PB3 in a multiple linear pattern: NH3‐N = (130.70±33.80) PB1 + (155.83±17.89) PB2 ‐ (85.44±37.69) PB3 + (42.43±1.05), R2 = 0.77, p < 0.0001, n = 45. The results indicated that both MLR and ANN models were suitable for predicting in vitro NH3‐N concentration of rations using CNCPS N‐fractions PB1, PB2, and PB3 as independent variables while the neural network model showed better performance in terms of greater r2, CCC and lower RMSPE between the observed and predicted values. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Via the bottom‐up synthetic strategy, we synthesized a pair of dodecanuclear metal clusters of Eu12(C2O4)9(R/S‐BNP)18(EtOH)6(H2O)6·8EtOH·7H2O (complex 2), which represent the largest axial chiral lanthanide metal clusters. In the structure, rare four‐pointed star coordination mode of oxalic acid is reported by this work. In addition, as a fluorescence sensor, the complex 2 exhibits high enantioselectivity for R‐/S‐BINOL‐TF2 (EF = 2.87) and other chiral binaphthyl derivatives. [ABSTRACT FROM AUTHOR]

Herein, the effect of metal contact doping on the scaled graphene field effect transistor (GFET) is investigated. Different from the traditional semiconductors device, the drain current of GFET is not inversely proportional to the channel length (LCH). The abnormal scaling behavior for drain current in GFETs can be attributed to the modification of channel resistance induced by the penetration of contact metal doping. In addition, the field‐effect mobility (μEF) of long channel GFET trend to saturate with decreasing LCH, which is consistent with the diffusive transport model. As the channel length is further scaled down, the μEF at first increases drastically and then decreases due to the enhanced effect of electrical property of graphene under the metal electrode as well as the contact resistance on the carrier transport of GFET. This study indicates that there will be a trade‐off between scaled channel length and the best performance of GFET. Further efforts should be made to modulate the properties of graphene both in channel and contact region to improve the scaling behavior of GFET. [ABSTRACT FROM AUTHOR]

The article titled "Metal-Contact-Induced Transition of Electrical Transport in Monolayer MoS2: From Thermally Activated to Variable-Range Hopping" was published in Advanced Electronic Materials in 2019. The article acknowledges additional funders that were not initially listed in the manuscript. The authors apologize for any inconvenience caused, but assure that these additions do not impact the conclusions of the paper. The authors of the article are Songang Peng, Zhi Jin, Yao Yao, Ling Li, Dayong Zhang, Jingyuan Shi, Xinnan Huang, Jiebin Niu, Yanhui Zhang, and Guanghui Yu. [Extracted from the article]

Modulating the electronic property of graphene by doping is essential for its device and circuit applications. Unfortunately, controllable p‐ and n‐type doping in top‐gated graphene field effect transistor (GFET) is reported. Here, the O3‐based atomic layer deposited Al2O3 layer as top gate dielectric is chosen. The epoxide functional group formed in the O3 process serves as effective interface trap sites. As the sweeping range of top gate voltage increases, the Dirac point position of GFET moves from positive voltage to negative voltage. The shift of the Dirac point voltage indicates the doping transition of graphene from p‐type to n‐type. The gate voltage dependent doping can be attributed to the charge exchange between graphene and interface trap sites. Furthermore, a trap‐dependent charge model is proposed to explain the transport mechanism in the doping process. This approach is promising to produce the complementary p‐ and n‐type top‐gated GFET for multiple applications. [ABSTRACT FROM AUTHOR]

Abstract: The Dirac point(s) in graphene field‐effect transistors (GFETs) are of great importance for electronic application. However, the lack of the effective means to distinguish the electrical properties of graphene at the contact and channel regions limits a clear understanding of their contributions to the Dirac point(s). A method, which can characterize the electrical properties of graphene under metal contact and in the channel, is developed, respectively. It is found that the Fermi levels of graphene at the contact and channel regions are quite different in the GFETs. The difference in Fermi levels results in the penetration of the doping effect under the contact into the channel with a length as long as 1 µm. The difference also causes the double Dirac point feature in the long‐channel GFET due to the combined graphene properties both in contact and channel. One of the two Dirac points diminished in short‐channel GFET due to the penetration of doping effect under the contact. The study demonstrates that the electrical behavior of short‐channel GFET is dominated by the contact region. This paces a way to deeply understand and further improve the performances of GFETs by controlling the Fermi levels in the whole devices. [ABSTRACT FROM AUTHOR]

γ-Amino butyric acid (GABA) and proline play a crucial role in protecting plants during various environmental stresses. Their synthesis is from the common precursor glutamic acid, which is catalyzed by glutamate decarboxylase and Δ1-pyrroline-5-carboxylate synthetase respectively. However, the dominant pathway under water stress has not yet been established. To explore this, excised tobacco leaves were used to simulate a water-stress condition. The results showed GABA content was much higher than that of proline in leaves under water-deficit and non-water-deficit conditions. Specifically, the amount of GABA significantly increased compared to proline under continuous water loss for 16 h, indicating that GABA biosynthesis is the dominant pathway from glutamic acid metabolism under these conditions. Quantitative reverse transcription polymerase chain reaction and protein Western gel-blot analysis further confirmed this. To explore the function of GABA accumulation, a system producing superoxide anion (O2−), peroxide hydrogen (H2O2), and singlet oxygen (1O2) was employed to investigate the scavenging role on free-radical production. The results demonstrated that the scavenging ability of GABA for O2−, H2O2, and 1O2 was significantly higher than that of proline. This indicated that GABA acts as an effective osmolyte to reduce the production of reactive oxygen species under water stress. [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenides (TMDs) have attracted intensive interests for its unique electronic, optical, and thermal properties. Doping is necessary to expand the application. However, the stability of doped materials has been overlooked. This study focuses on the stability of monolayer‐doped MoS2 with different vanadium (V) concentrations. It provides a quantitative assessment of the etching results. Findings indicate that the stability of MoS2 under different etching atmospheres follows the series of lightly doped MoS2, pristine MoS2, moderately doped MoS2, and highly doped MoS2. This research indicates that the stability of the material is linked to the bonding energy of cations and anions, as well as the amount of lattice distortion, which competes with one another. Low levels of V doping do not lead to significant lattice distortion, and the binding energy between sulfur (S) and V surpasses that of molybdenum (Mo), which is the primary factor. Excessive doping results in lattice distortion, which leads to a multitude of defects and a reduction in durability. This work is important for guiding the assessment of the reliability, the protection of degradation, and application scenarios of TMDs. [ABSTRACT FROM AUTHOR]

An understanding of the charge transport of atomically thin molybdenum sulfide (MoS2) beneath the metal electrode is important to the fabrication of high performance MoS2 devices and circuits with low ohmic contact resistance. However, the carrier‐transport mechanism in monolayer MoS2 under the metal contact has remained elusive due to the difficulty of measuring the electrical properties of MoS2 in contact regions. A method to distinguish the electrical properties of monolayer MoS2 in the contact and channel regions is presented. Temperature‐dependent measurement reveals that the carriers are thermally activated in the channel region. In contrast, they are variable‐range hopping in the contact region. This difference can be attributed to the localization of the MoS2 electronic states caused by metal‐induced gap states. The variable‐range hopping transport in MoS2 under contact causes a reduction of the carrier mobility and an increase in the contact resistance. This work is not only important for fundamental understanding of metal–MoS2 contact but also helpful for further improving the performance of MoS2 devices. [ABSTRACT FROM AUTHOR]

Reconfigurable artificial synapse with synaptic responses modulated between excitatory and inhibitory modes is critical for building artificial intelligence systems. However, it is still a challenge to realize such reconfigurability with a simple single‐gated transistor. Here, hydrogen‐rich silicon nitride film is employed as the gate dielectric to construct a single‐gate controlled graphene‐based artificial synapse to realize the reconfigurable synaptic responses. In this dielectric, both traps and movable hydrogen ions are introduced to induce the carrier trapping effect and the capacitive gating effect, respectively. Comparatively, the capacitive gating effect needs stronger electrical fields excitation and can significantly modulate the graphene channel in a longer time. Utilizing the carrier trapping effect and the ambipolar property of graphene, the fundamental potentiation and depression behaviors can be emulated in each response mode. Then, utilizing the capacitive gating effect, the reconfiguration between excitatory and inhibitory response modes can be achieved. All synaptic responses only depend on the signals inputted through the back‐gate electrode, which is distinctively different from previous dynamic devices with additional modulating terminals. Such reconfiguration feature provides the artificial synapse the ability to emulate some complicated biological behaviors in future artificial intelligence systems, such as the adjustable perception of different external stimuli under different conditions. [ABSTRACT FROM AUTHOR]