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Objective To explore the characteristics of thoracic and lumbar mobility in patients with degenerative spine deformity (DSD). Methods A total of 60 patients with degenerative spine deformity (DSD) admitted in our hospital from May 2018 to May 2021 were recruited in the study, and another 40 healthy individuals who taking physical examination during same period served as control group. The patients including 39 cases of scoliosis convex to the left and 21 cases to the right. A handheld joint actiometer was used to measure thoracic vertebrae left-right lateral flexion, left-right rotation, and lumbar vertebrae flexion and extension, left and right lateral flexion in the deformed group and control group. The parameters, including coronal Cobh angle (CA) and apical vertebra (AV) were measured on the X-ray films of the whole spine in the standing position. The apical vertebra rotation (AVR) was measured on the cross-sectional T2W1 image of MRI. Differences in thoracic and lumbar vertebrae range of motion (ROM) were compared between the 2 groups, and the correlation of thoracic and lumbar vertebrae ROM with AVR and CA angle were analyzed in the deformed group. Results The overall ROM of the lumbar lateral flexion, flexion, extension and the ROM of the thoracic vertebra rotation were significantly smaller than those of the control group (P < 0.01). In the left-sided curved deformities, the lumbar flexion, extension, lateral flexion (concave) and thoracic rotation (concave, convex) were significantly smaller than those in the control group (P < 0.05). In the right-sided curved deformities, the lumbar extension, lumbar flexion (concave, convex), and thoracic rotation (concave, convex) were significantly small than in the control group (P < 0.05). In the deformed group, the lumbar lateral flexion (convex) was significantly negatively correlated with both CA angle (r=-0.282, P=0.035) and AVR (r=-0.343, P=0.010). Conclusion DSD patients have limitations in spinal mobility in all directions. The mobility limitation for lumbar spine mainly focuses on flexion and extension (sagittal plane) and lateral flexion (coronal plane), while mobility limitation for thoracic vertebrae mainly concentrates on rotation. The lateral flexion mobility on the convex side are closely associated with the Cobb angle and AVR.

There are four sizable black soil regions throughout the world, all of which are valuable natural resources. The black soil region in Northeast China is a major foundation for grain production. Serious risks of soil erosion do exist, and they have an immediate impact on both the country's food security and future ecological security. Many soil and water conservation measures have been put in place to control soil erosion. However, how effective and suitable are these measures? Currently, systematic analyses and assessments are lacking. The objective of this study was to assess the effectiveness and suitability of soil and water conservation measures on hillslopes using the comprehensive index method and the Pressure–State–Response model. The categorization of effectiveness and suitability of these measures were similar for both methods: that is, very effective and suitable measures included no-tillage + straw mulch and ridge belt or contour ridge. The two methods validated one another. Thus, this categorization standard is useful for choosing the best soil and water conservation measures for different soil erosion regions. [ABSTRACT FROM AUTHOR]

This study aims to provide a precise assessment of the distribution of educational facilities within the Guangdong–Hong Kong–Macao Greater Bay Area, serving as a crucial foundation for managing educational resource allocation and enhancing the quality of educational services. Utilizing a kernel density analysis, global autocorrelation analysis, and geographic detectors, this research systematically analyzes the spatial distribution characteristics and influencing factors of educational facilities in the area. The findings reveal significant geographical disparities in facility distribution with dense clusters in urban centers such as Guangzhou and Shenzhen, and less dense distributions in peripheral areas like Zhongshan and Macau. These facilities exhibit a multi-center cluster pattern with strong spatial autocorrelation, mainly influenced by the population size and economic and urban development levels. The results provide actionable insights for refining educational planning and resource allocation, contributing to the enhancement of educational quality across diverse urban landscapes. [ABSTRACT FROM AUTHOR]

The twist-bend nematic liquid crystal phase is a three-dimensional fluid in which achiral bent molecules spontaneously form an orientationally ordered, macroscopically chiral, heliconical winding of a ten nanometer-scale pitch in the absence of positional ordering. Here, the structure of the twist-bend phase of the bent dimer CB7CB and its mixtures with 5CB is characterized, revealing a hidden invariance of the self-assembly of the twist-bend structure of CB7CB, such that over a wide range of concentrations and temperatures, the helix pitch and cone angle change as if the ground state for a pitch of the TB helix is an inextensible heliconical ribbon along the contour formed by following the local molecular long axis (the director). Remarkably, the distance along the length for a single turn of this helix is given by 2πRmol, where Rmol is the radius of bend curvature of a single all-trans CB7CB molecule. This relationship emerges from frustrated steric packing due to the bent molecular shape: space in the fluid that is hard to fill attracts the most flexible molecular subcomponents, a theme of nanosegregation that generates self-assembled, oligomer-like correlations of interlocking bent molecules in the form of a brickwork-like tiling of pairs of molecular strands into duplex double-helical chains. At higher temperatures in the twist-bend phase, the cone angle is small, the director contour is nearly along the helix axis z, and the duplex chains are sequences of biaxial elements formed by overlapping half-molecule pairs, with an approximately 45° rotation of the biaxis between each such element along the chain. [ABSTRACT FROM AUTHOR]

Background: Lymph node characteristics markedly affect nasopharyngeal carcinoma (NPC) prognosis. Matted node (MN), an important characteristic for lymph node, lacks explored MRI‐based prognostic implications. Purpose: Investigate MRI‐determined MNs' prognostic value in NPC, including 5‐year overall survival (OS), distant metastasis‐free survival (DMFS), local recurrence‐free survival (LRFS), progression‐free survival (PFS), and its role in induction chemotherapy (IC). Study Type: Retrospective cohort survival study. Population: Seven hundred ninety‐two patients with non‐metastatic NPC (female: 27.3%, >45‐year old: 50.1%) confirmed by biopsy. Field Strength/Sequence: 5‐T/3.0‐T, T1‐, T2‐ and post‐contrast T1‐weighted fast spin echo sequences acquired. Assessment: MNs were defined as ≥3 nodes abutting with intervening fat plane replaced by extracapsular nodal spread (ENS). Patients were observed every 3 months for 2 years and every 6 months for 5 years using MRI. Follow‐up extended from treatment initiation to death or final follow‐up. MNs were evaluated by three radiologists with inter‐reader reliability calculated. A 1:1 matched‐pair method compared survival differences between MN‐positive patients with or without IC. Primary endpoints (OS, DMFS, LRFS, PFS) were calculated from therapy initiation to respective event. Statistical Tests: Kappa values assessed inter‐reader reliability. Correlation between MN, ENS, and LNN was studied through Spearman's correlation coefficient. Clinical characteristics were calculated via Fisher's exact, Chi‐squared, and Student's t‐test. Kaplan–Meier curves and log‐rank tests analyzed all time‐to‐event data. Confounding factors were included in Multivariable Cox proportional hazard models to identify independent prognostic factors. P‐values <0.05 were considered statistically significant. Results: MNs incidence was 24.6%. MNs independently associated with decreased 5‐year OS, DMFS, and PFS; not LRFS (P = 0.252). MN‐positive patients gained significant survival benefit from IC in 5‐year OS (88.4% vs. 66.0%) and PFS (76.4% vs. 53.5%), but not DMFS (83.1% vs. 69.9%, P = 0.145) or LRFS (89.9% vs. 77.8%, P = 0.140). Data Conclusion: MNs may independently stratify NPC risk and offer survival benefit from IC. Evidence Level: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Exposure to PM2.5, a harmful type of air pollution, has been associated with compromised male reproductive health; however, it remains unclear whether such exposure can elicit transgenerational effects on male fertility. Here, we aim to examine the effect of paternal exposure to real-world PM2.5 on the reproductive health of male offspring. We have observed that paternal exposure to real-world PM2.5 can lead to transgenerational primary hypogonadism in a sex-selective manner, and we have also confirmed this phenotype by using an external model. Mechanically, we have identified small RNAs (sRNAs) that play a critical role in mediating these transgenerational effects. Specifically, miR6240 and piR016061, which are present in F0 PM sperm, regulate intergenerational transmission by targeting Lhcgr and Nsd1, respectively. We have also uncovered that piR033435 and piR006695 indirectly regulate F1 PM sperm methylation by binding to the 3′-untranslated region of Tet1 mRNA. The reduced expression of Tet1 resulted in hypermethylation of several testosterone synthesis genes, including Lhcgr and Gnas, impaired Leydig cell function and ultimately led to transgenerational primary hypogonadism. Our findings provide insights into the mechanisms underlying the transgenerational effects of paternal PM2.5 exposure on reproductive health, highlighting the crucial role played by sRNAs in mediating these effects. The findings underscore the significance of paternal pre-conception interventions in alleviating the adverse effects of environmental pollutants on reproductive health. [ABSTRACT FROM AUTHOR]

In this study, we examined the impact of dexmedetomidine (DEX) on the effectiveness of epidural analgesia and labor outcomes. We administered different doses of DEX combined with 0.1% ropivacaine for epidural analgesia to evaluate the clinical effects and safety. To assess the effects of different concentrations of DEX in parturient women receiving epidural analgesia, we conducted a randomized double‐blind trial. We selected 400 parturient women and randomly assigned them to 4 groups, with 100 parturient women in each group: S0.1 (0.1 µg/mL DEX), S0.2 (0.2 µg/mL DEX), S0.3 (0.3 µg/mL DEX), and a control group (0.3 µg/mL sufentanil). Post‐analgesia, we recorded the Bromage score, duration of labor, method of delivery, bleeding, neonatal Apgar score, adverse reactions, and maternal satisfaction. The number of patients with a Bromage score of ≥2 and the incidence of bradycardia were higher in the S0.3 group compared with the other 3 groups (P <.05), whereas the high satisfaction rate was lower in the S0.3 group (P <.05). Moreover, we found that the number of times that additional patient‐controlled analgesia was administered was higher in the S0.1 group compared with the remaining 3 groups (P <.05). The control group exhibited a higher incidence of pruritus than the other 3 groups (P <.05). In conclusion, when administering spinal anesthesia for the relief of labor pain, epidural analgesia with 0.1% ropivacaine combined with 0.2 µg/mL DEX provides relatively ideal analgesic effects, higher maternal satisfaction, and reduces the incidence of pruritus, compared with the combination of 0.1% ropivacaine and 0.3 µg/mL sufentanil. [ABSTRACT FROM AUTHOR]