As part of an international effort to completely sequence the rice genome, we have produced a fine bacterial artificial chromosome (BAC)-based physical map of the Oryza sativa japonica Nipponbare ...chromosome 4 through an integration of 114 sequenced BAC clones from a taxonomically related subspecies O. sativa indica Guangluai 4 and 182 RFLP and 407 expressed sequence tag (EST) markers with the fingerprinted data of the Nipponbare genome. The map consists of 11 contigs with a total length of 34.5 Mb covering 94% of the estimated chromosome size (36.8 Mb). BAC clones corresponding to telomeres, as well as to the centromere position, were determined by BAC-pachytene chromosome fluorescence in situ hybridization (FISH). This gave rise to an estimated length ratio of 5.13 for the long arm and 2.9 for the short arm (on the basis of the physical map), which indicates that the short arm is a highly condensed one. The FISH analysis and physical mapping also showed that the short arm and the pericentromeric region of the long arm are rich in heterochromatin, which occupied 45% of the chromosome, indicating that this chromosome is likely very difficult to sequence. To our knowledge, this map provides the first example of a rapid and reliable physical mapping on the basis of the integration of the data from two taxonomically related subspecies.
The complete genome sequence of cultivated rice (
Oryza sativa
) provides an unprecedented opportunity to understand the biology of this model cereal. An essential and necessary step in this effort ...is the determination of the coding information and expression patterns of each sequenced chromosome. Here, we report an analysis of the transcriptional activity of rice chromosome 4 using a tiling path microarray based on PCR-generated genomic DNA fragments. Six representative rice organ types were examined using this microarray to catalog the transcribed regions of rice chromosome 4 and to reveal organ- and developmental stage–specific transcription patterns. This analysis provided expression support for 82% of the gene models in the chromosome. Transcriptional activities in 1643 nonannotated regions were also detected. Comparison with cytologically defined chromatin features indicated that in juvenile-stage rice the euchromatic region is more actively transcribed than is the transposon-rich heterochromatic portion of the chromosome. Interestingly, increased transcription of transposon-related gene models in certain heterochromatic regions was observed in mature-stage rice organs and in suspension-cultured cells. These results suggest a close correlation between transcriptional activity and chromosome organization and the developmental regulation of transcription activity at the chromosome level.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Cognitive impairment (CI) is common among patients with chronic kidney disease (CKD), and is associated with a poor prognosis. We assessed the prevalence and associated factors of CI in patients with ...CKD. A systematic review and meta-analysis were conducted by searching PubMed, Embase, and the Web of Science through December 1, 2023. Random effects models were performed with subgroup analyses to further explore the heterogeneity. 50 studies involving 25,289 CKD patients were included. The overall prevalence of CI was 40% (95% confidence interval 33-46). The pooled prevalence of CI was relatively higher in CKD patients from Africa (58%), Asia (44%) and America (37%). Attention and executive dysfunction appeared to be the most common manifestations. The prevalence of CI was higher among patients with hemodialysis (53%) and peritoneal dialysis (39%) than those without dialysis (32%) and post-kidney transplanted (26%). In addition, advanced age, the presence of diabetes and hypertension might increase the risk of CI in CKD patients. People with CKD have a high prevalence of CI, especially in patients with hemodialysis. An early and comprehensive screening for CI in CKD patients is needed to improve clinical outcomes.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Photomechanical molecular crystals are receiving much attention due to their efficient conversion of light into mechanical work and advantages including faster response time; higher Young's modulus; ...and ordered structure, as measured by single‐crystal X‐ray diffraction. Recently, various photomechanical crystals with different motions (contraction, expansion, bending, fragmentation, hopping, curling, and twisting) are appearing at the forefront of smart materials research. The photomechanical motions of these single crystals during irradiation are triggered by solid‐state photochemical reactions and accompanied by phase transformation. This Minireview summarizes recent developments in growing research into photoresponsive molecular crystals. The basic mechanisms of different kinds of photomechanical materials are described in detail; recent advances in photomechanical crystals for promising applications as smart materials are also highlighted.
Going through the motions: Photomechanical molecular crystals receive much attention due to their efficient conversion of light into mechanical work, as well as faster response time, higher Young's modulus, and ordered structure (see figure). Recent developments in growing research into photoresponsive molecular crystals is summarized.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Noncollinear antiferromagnetic materials have received dramatically increasing attention in the field of spintronics as their exotic topological features such as the Berry-curvature-induced anomalous ...Hall effect and possible magnetic Weyl states could be utilized in future topological antiferromagnetic spintronic devices. In this work, we report the successful integration of the antiferromagnetic metal Mn3Sn thin films onto ferroelectric oxide PMN-PT. By optimizing growth, we realized the large anomalous Hall effect with small switching magnetic fields of several tens mT fully comparable to those of bulk Mn3Sn single crystals, anisotropic magnetoresistance and negative parallel magnetoresistance in Mn3Sn thin films with antiferromagnetic order, which are similar to the signatures of the Weyl state in bulk Mn3Sn single crystals. More importantly, we found that the anomalous Hall effect in antiferromagnetic Mn3Sn thin films can be manipulated by electric fields applied onto the ferroelectric materials, thus demonstrating the feasibility of Mn3Sn-based topological spintronic devices operated in an ultralow power manner.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
It is widely believed that raters’ cognition is an important aspect of writing assessment, as it has both logical and temporal priority over scores. Based on a critical review of previous research in ...this area, it is found that raters’ cognition can be boiled to two fundamental issues: building text images and strategies for articulating scores. Compared to the scoring contexts of previous research, the TEM 8 integrated writing task scoring scale has unique features. It is urgent to know how raters build text images and how they articulate scores for text images in the specific context of rating TEM8 compositions. In order to answer these questions, the present study conducted qualitative research by considering raters as problem solvers in the light of problem-solving theory. Hence, 6 highly experienced raters were asked to verbalize their thoughts simultaneously while rating TEM 8 essays, supplemented by a retrospective interview. Analyzing the collected protocols, we found that with regard to research question 1, the raters went through two stages by setting building text images as isolated nodes and building holistic text images for each dimension as two sub-goals, respectively. In order to achieve the first sub-goal, raters used strategies such as single foci evaluating, diagnosing, and comparing; for the second sub-goal, they mainly used synthesizing and comparing. Regarding the second question, the results showed that they resorted to two groups of strategies: demarcating boundaries between scores within a dimension and discriminating between dimensions, each group consisting of more specific processes. Each of the extracted processes was defined clearly and their relationships were delineated, on the basis of which a new working model of the rating process was finalized. Overall, the present study deepens our understanding of rating processes and provides evidence for the scoring validity of the TEM 8 integrated writing test. It also provides implications for rating practice, such as the need for the distinction between two types of analytical rating scales.
Recently, increasing numbers of box tunnels have been built in urban areas due to their high space utilization. Rectangular boring machines are commonly used in box tunneling, and tunnels are driven ...by thrusting prefabricated linings. Sometimes, when a tunnel machine encounters obstructions, such as boulders or steel plates, the excavation efficiency decreases. The tunnel drive has to be suspended to remove obstructions in the working chamber. Mostly, for ordinary machines, obstruction removal is carried out under open air, and the working face is no longer fully supported. This paper investigates the working face stability of box tunnels redundant on the situation in which the working face is not fully supported. According to practical experiences, the support pressure provided by the remains in the chamber is explored, and unsupported and supported areas at the face are identified. To analyze the ground stability, an analytical model is proposed by modifying the traditional silo-wedge model. In the proposed model, the wedge and prim blocks are divided into sub-blocks, and the interactions between the blocks are taken into account. Based on the proposed model, the solution of the pressure for stability is derived through limit equilibrium analysis. Parametric analysis is carried out to determine the effects of the factors on stability. A comparison of the proposed model and the traditional model is performed, and the rationality of the current model is discussed. This paper ends with the validation of the current model by investigating a case of a box tunnel in Suzhou, China.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Accurate and fast detection of pavement distress can provide reliable and effective technical support for pavement maintenance and rehabitation. Recently, deep learning has been widely used in ...pavement distress detection. However, its application is still limited by the laborious and difficult annotation process due to the complex topology of pavement distress. In this study, we propose a pavement anomaly detection network (PAD Net), which is a semi-supervised learning approach based on generative adversarial networks for identifying pixel-level anomalous image segments. We build a mapping function for unpaired abnormal and normal pavement images through a framework containing two generators and three novel discriminators. The framework is capable of maintaining background pixels and modifying anomalous foreground regions with the help of multi-style discriminators that consider interrelationships of multi-scale generated images. Meanwhile, pixel-level abnormal areas are detected through an end-to-end mask channel. Experiments show that our approach is able to achieve 80.75% accuracy on our dataset without pixel-level or patch-level annotations. Quantitative comparisons with several prior semi-supervised methods demonstrate the superiority of our approach.
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