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Self-propelled bacteria are marvels of nature with a potential to power dynamic materials and microsystems of the future. The challenge lies in commanding their chaotic behavior. By dispersing swimming Bacillus subtilis in a liquid crystalline environment with spatially varying orientation of the anisotropy axis, we demonstrate control over the distribution of bacterial concentration, as well as the geometry and polarity of their trajectories. Bacteria recognize subtle differences in liquid crystal deformations, engaging in bipolar swimming in regions of pure splay and bend but switching to unipolar swimming in mixed splay-bend regions. They differentiate topological defects, heading toward defects of positive topological charge and avoiding negative charges. Sensitivity of bacteria to preimposed orientational patterns represents a previously unknown facet of the interplay between hydrodynamics and topology of active matter.

Stimuli-responsive liquid crystal elastomers with molecular orientation coupled to rubber-like elasticity show a great potential as elements in soft robotics, sensing, and transport systems. The orientational order defines their mechanical response to external stimuli, such as thermally activated muscle-like contraction. Here we demonstrate a dynamic thermal control of the surface topography of an elastomer prepared as a coating with a pattern of in-plane molecular orientation. The inscribed pattern determines whether the coating develops elevations, depressions, or in-plane deformations when the temperature changes. The deterministic dependence of the out-of-plane dynamic profile on the in-plane orientation is explained by activation forces. These forces are caused by stretching-contraction of the polymer networks and by spatially varying molecular orientation. The activation force concept brings the responsive liquid crystal elastomers into the domain of active matter. The demonstrated relationship can be used to design coatings with functionalities that mimic biological tissues such as skin. Liquid crystal elastomers are anisotropic rubbers which can be actuated by an external trigger. Here the authors develop elastomer coatings with pre-patterned molecular orientation that induces deterministic topography changes in response to changes in temperature.

Active matter exhibits remarkable collective behaviour in which flows, continuously generated by active particles, are intertwined with the orientational order of these particles. The relationship remains poorly understood as the activity and order are difficult to control independently. Here we demonstrate important facets of this interplay by exploring the dynamics of swimming bacteria in a liquid crystalline environment with predesigned periodic splay and bend in molecular orientation. The bacteria are expelled from the bend regions and condense into polar jets that propagate and transport cargo unidirectionally along the splay regions. The bacterial jets remain stable even when the local concentration exceeds the threshold of bending instability in a non-patterned system. Collective polar propulsion and the different roles of bend and splay are explained by an advection–diffusion model and by numerical simulations that treat the system as a two-phase active nematic. The ability of prepatterned liquid crystalline medium to streamline the chaotic movements of swimming bacteria into polar jets that can carry cargo along a predesigned trajectory opens the door for potential applications in microscale delivery and soft microrobotics. The relationship between the dynamics and spatial order of active matter gives rise to a rich phenomenology that is not fully understood. A study of bacteria swimming in a patterned liquid crystalline environment is a case in point, and provides a way to streamline the chaotic movements of swimming bacteria into polar jets.

Alfalfa ( Medicago sativa L.) is an important legume forage known for its high yield, quality, and adaptability. However, due to its cross-pollination and tetraploid inheritance characteristics, biotechnologies such as genetic modification and gene editing are challenging to be utilized in the practice of alfalfa breeding. In this study, a MsJAR1 gene involved in jasmonic acid (JA)pathway was overexpressed into ‘Zhongmu No.1’ alfalfa, and the effects of MsJAR1 gene on alfalfa development were analyzed. Subcellular localization results indicated that the MsJAR1 protein was located to chloroplast. Compared to wildtype (WT), MsJAR1 overexpressed alfalfa plants displayed smaller leaves, reduced internode distance, increased lateral branches and plant height. Moreover, anatomical analysis revealed that xylem and phloem area decreased in leaves but increased in stems of MsJAR1 overexpressed alfalfa. Except intercellular CO₂, photosynthetic rates, stomatal conductance, and transpiration were significantly higher than in MsJAR1 overexpressed alfalfa. Comparative transcriptomics results showed that 12,046 DEGs were identified between transgenic alfalfa (OE-1 and OE-2) and WT. The DEGs were significantly enriched in ribosome, glycolysis / gluconeogenesis and tricarboxylic acid cycle pathways. Therefore, it is speculated that the MsJAR1 gene affects the growth and development of alfalfa by regulating photosynthesis-related pathways.

Liquid crystal (LC) micro-droplet arrays are elegant systems that have a range of applications, such as chemical and biological sensing, due to a sensitivity to changes in surface properties and strong optical activity. In this work, we utilize self-assembled monolayers (SAMs) to chemically micro-pattern surfaces with preferred regions for LC occupation. Exploiting discontinuous dewetting, dragging a drop of fluid over the patterned surfaces demonstrates a novel, high-yield method of confining LC in chemically defined regions. The broad applicability of this method is demonstrated by varying the size and LC phase of the droplets. Although the optical textures of the droplets are dictated by topological constraints, the additional SAM interface is shown to lock in inhomogeneous alignment. The surface effects are highly dependent on size, where larger droplets exhibit asymmetric director configurations in nematic droplets and highly knotted structures in cholesteric droplets.

Erectile dysfunction (ED) is a major sexual problem for men. Nogo-B receptor (NgBR) has been found to be involved in the regulation of vascular remodeling and angiogenesis. The present study explores the effects of NgBR in penile corpus cavernosum in rats with diabetic ED. Firstly, the ED model of Sprague Dawley rats was established. Hematoxylin-eosin staining and Masson staining were conducted to observe pathological morphology. Immunochemical assay was adopted to detect α-smooth muscle actin (α-SMA), NgBR and intercellular cell adhesion molecule-1 (ICAM-1) expression. Reverse transcription quantitative polymerase chain reaction assay and Western blot analysis were carried out for the assessment of NgBR, factors correlated to ICAM-1, including steroid receptor coactivator (SRC) and proline-rich tyrosine kinase2 (PYK2), and factors associated with apoptosis, including B-cell lymphoma-2 (Bcl-2), Bcl-2 associated protein X (Bax), caspase 3 and cleaved-caspase 3. The results found that capillaries and vascular smooth muscle cell content reduced, and NgBR and ICAM-1 were elevated in rats with diabetic ED. si-NgBR relieved ED by decreasing penile corpus cavernosum smooth muscle systolic percentage and increasing erectile time and rate, intracavernous pressure (ICP)/mean arterial pressure (MAP) and diastolic percentage, improving the pathological changes and inhibiting cavernosum cell apoptosis. si-NgBR also resulted in the down-regulation of ICAM-1 and downstream SRC and PYK2 and promoted α-SMA expression. In conclusion, si-NgBR can provide a potential therapy for diabetic ED in rats by down-regulating ICAM-1, SRC and PYK2, making it a potential therapeutic option for diabetic ED.

Background Glioma has the characteristics of high incidence and mortality, and is a common malignant tumor of the central nervous system. Circular RNAs (circRNAs) have been reported to play vital roles in progression of cancer including glioma, and circKIF4A is up-regulated in glioma tissues. However, its role and mechanisms in gliomas are unclear. Methods circKIF4A and miR-139-3p were determined by qRT-PCR. Transwell assay, wound-healing assay, cell colony formation and flow cytometry were performed to measure cell invasion, migration, proliferation and apoptosis. Western blotting was used to evaluate Wnt/β-catenin pathway-related protein. Luciferase reporter assays confirmed the relationship among circKIF4A, miR-139-3p and Wnt5a. Sphere formation was performed to measure the ability of glioma-initiating cells (GICs) spheroid formation. A nude mouse xenograft model was established and immunohistochemical staining was used to detect Ki-67 and Wnt5a levels. Results circKIF4A and Wnt5a were up-regulated and miR-139-3p was down-regulated in both glioma cells and tissues. circKIF4A promoted Wnt5a expression by sponging miR-139-3p. Knockdown of circKIF4A inhibited the colony formation ability, migration and invasion, and promoted the apoptosis of glioma cells by regulating miR-139-3p. Knockdown of circKIF4A inhibited Wnt/β-catenin signaling pathway and proliferation-related signal via miR-139-3p. Furthermore, knockdown of circKIF4A or overexpression of miR-139 suppressed the ability of sphere formation of GICs and inhibitd Wnt/β-catenin signaling pathway and proliferation-related signal in GICs. Additionally, depletion of circKIF4A decreased the expression level of Wnt5a and Ki-67, inhibited tumorigenesis in xenograft modes. Conclusion circKIF4A was overexpressed in glioma, and knockdown of circKIF4A suppressed glioma progression via miR-139-3p/Wnt5a axis. The results indicated that circKIF4A may be a potential target for clinical treatment of glioma.

Objective. A retrospective analysis of clinical characteristics and immunological manifestations of primary Sjogren’s syndrome (pSS) patients with or without renal involvement was conducted in order to elucidate the potential risk factors of renal damage in pSS and evaluate the condition. Methods. A total of 1002 patients, who fulfilled the 2002 classification criteria for pSS from the Second Affiliated Hospital of Shanxi Medical University, were enrolled in the cross-sectional study. Clinical, immunological, and histological characteristics were compared between pSS patients with and without renal involvement, and potential risk factors of renal involvements in pSS patients were examined by multivariate analysis. Results. Among these pSS patients, there were 162 cases (16.17%) with and 840 cases (83.83%) without renal damage. Serious edema of both lower limbs, interstitial nephritis, and renal tubular acidosis were found in the pSS with renal damage group. Compared with simple pSS patients, the levels of creatinine, cystatin C, and alpha-1-microglobulin (α1-MG) in the pSS with renal damage group were significantly increased. The difference between the two groups was statistically significant (P<0.05). The AUC of the combination of creatinine and α1-MG and creatinine, α1-MG, and creatinine was statistically larger than that of creatinine, and the biomarker of the biggest AUC is the combination of creatinine and α1-MG. Conclusion. The main clinical manifestations of pSS with renal damage were edema of the lower limbs, interstitial nephritis, and renal tubular acidosis. Creatinine and α1-MG are effective indicators for renal function in pSS, which may provide a better understanding for clinical decision-making.

Targeted poverty alleviation is a major national initiative in China. The Hotan region, located within the four prefectures of Southern Xinjiang, is one of the 14 contiguous poverty-stricken areas in China as well as a quintessential inland arid zone. Water scarcity is the primary constraint on development in the Hotan region and a major bottleneck for Northwest China as a whole. However, previous assessments of the effectiveness of poverty alleviation measures have primarily focused on industrial growth itself, lacking an analysis of the adaptability between key regional resource elements and industrial poverty alleviation measures. The core of promoting targeted poverty alleviation in arid regions is properly managing the relationships within the “industry–water resources” system and achieving a balance between resource use, environmental capacity, and economic development. Focusing on the coordinated development of industry and water resources, this study evaluates the spatio-temporal evolution of the industry–water resource relationships in the Hotan region after the implementation of the targeted poverty alleviation policy with the aim of measuring the sustainability of industrial poverty alleviation outcomes in this arid region. The results indicate the following: (1) The targeted poverty alleviation policy has reduced industrial water consumption. Following the policy’s implementation, industrial water consumption decreased by 541 million m3, driven by improvements in water use intensity and shifts in the industrial structure. The primary contributor to this reduction was enhanced water use efficiency within the primary sector. (2) The policy exacerbated the misallocation of water resources relative to industrial output across the region. The Gini coefficient for water resources versus GDP across Hotan’s eight counties and cities rose from 0.26 to 0.32, indicating a shift from a ‘relatively balanced’ to a ‘moderately imbalanced’ allocation. Therefore, achieving sustainable poverty alleviation in this arid region necessitates enhanced coordination between industrial development and water resources.

Non-homologous end joining (NHEJ) is a major pathway to repair DNA double-strand breaks (DSBs), which can display different types of broken ends. However, it is unclear how NHEJ factors organize to repair diverse types of DNA breaks. Here, through systematic analysis of the human NHEJ factor interactome, we identify PAXX as a direct interactor of Ku. The crystal structure of PAXX is similar to those of XRCC4 and XLF. Importantly, PAXX-deficient cells are sensitive to DSB-causing agents. Moreover, epistasis analysis demonstrates that PAXX functions together with XLF in response to ionizing radiation-induced complex DSBs, whereas they function redundantly in response to Topo2 inhibitor-induced simple DSBs. Consistently, PAXX and XLF coordinately promote the ligation of complex but not simple DNA ends in vitro . Altogether, our data identify PAXX as a new NHEJ factor and provide insight regarding the organization of NHEJ factors responding to diverse types of DSB ends. DNA double-strand breaks (DSBs), a highly deleterious form of DNA damage, are associated with multiple types of broken ends. Here, the authors identify a XRCC4-like factor that functions in the non-homologous end-joining DNA repair pathway to repair DSBs with complex broken ends.