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The influence of chromium‐bearing filler sand on the transformation of inclusions in high‐Mn and high‐Al steel under various reaction times and Mn content levels is studied, and the mechanism of filler sand intrusion into the steel matrix is analyzed. It is demonstrated that an inclusion containing Cr2O3 is discovered. The evolution pathway of oxide inclusions is identified as Al2O3–MnO → Al2O3–MnO–SiO2 → Al2O3–MnO–SiO2–Cr2O3(Cr2O3 + MnO–SiO2) → Al2O3–MnO–Cr2O3–MgO·Al2O3. It is noteworthy that Cr2O3 inclusions tend to diffuse from the outside inward, but the internal content remains almost unchanged, which is due to the strong diffusion hindrance of SiO2. The formation of a liquid phase in the filler sand is a necessary condition for its infiltration into the steel matrix. The critical liquid‐phase content that results in the formation of Cr2O3 inclusions is 42%, which contains 5–8% of Cr2O3. The formation of pore channels provides favorable conditions for sand penetration, with the maximum penetration depth reaching up to 29 mm. Large sand inclusion particles reach millimeter scale in size and are distributed quite randomly. Chemical reactions at the steel/sand interface can lead to an increase in the total oxygen (T.O) content in the steel. The reaction time has little effect on the T.O content, while the Mn content in the steel has a significant impact, with an increase of up to 41 ppm. During the smelting stage, the filler sand can enter the molten steel, thereby affecting the quality of the product. [ABSTRACT FROM AUTHOR]

Developing novel filler sands has garnered significant interest in improving the ladle's free‐opening rate and enhancing the cleanliness of high‐Mn and high‐Al steel. Laboratory studies explore the effect of adding Cr2O3 powder on the sintering behavior of chromite‐based filler sands. Furthermore, interfacial phenomena are examined between the sands and the steel grades, varying in Mn contents. The results demonstrate that adding Cr2O3 power plays a role in inhibiting the liquid phase formation in the sand. With a 16% addition, the steel (Mn mass% = 30) reacts with the sand, leading to the shape of a spinel phase, specifically (Mn, Fe, Mg)O·(Al, Cr)2O3, which facilitates the separation of the liquid phase. The reduction of FeO to Fe by Mn, Al, and C in steel, especially Al, is hindered by adding Cr2O3, resulting in a suitable sintering degree that ultimately benefits ladle free‐opening. SiO2 is crucial for forming the liquid phase during the sintering process. The SiO2 content of the sand should be about 20% to achieve optimal sintering effects. Chromite sand for casting is not suitable for the steels. The mixed sand presented in the current study demonstrates potential as a suitable filler sand for the steel (20 ≤ Mn mass% ≤ 30). [ABSTRACT FROM AUTHOR]

Alpine Rhododendron species are prominent constituents and renowned ornamental plants in alpine ecosystems. Consequently, evaluating the genetic variation in embolism resistance within the genus Rhododendron and predicting their adaptability to future climate change is important. Nevertheless, the assessment of embolism resistance in Rhododendron species remains limited. This investigation aimed to examine leaf vulnerability to embolism across ten alpine Rhododendron species, which are frequently employed as ornamental species in Rhododendron forests in Southwest China. The study analyzed the correlation between embolism resistance and various morphological traits, while also conducting water control experiments to evaluate the relationship between embolism resistance and drought resistance. The outcomes indicated pronounced variations in leaf vulnerability to embolism among species, as reflected by the water potential at 50% of embolized pixels (P50). Furthermore, the leaf P50 exhibited a significant positive correlation with vessel diameter (D) (R2 = 0.44, P = 0.03) and vessel wall span (b) (R2 = 0.64, P = 0.005), while displaying a significant negative correlation with vessel reinforcement ((t/b)2) (R2 = 0.67, P = 0.004). These findings underscore the reliability of selecting species based on embolism vulnerability to preserve the diversity of alpine ecosystems and foster resilience to climate change. [ABSTRACT FROM AUTHOR]

Rosacea is a complex chronic inflammatory skin disorder with high morbidity. Pyroptosis is known as a regulated inflammatory cell death. While its association with immune response to various inflammatory disorders is well established, little is known about its functional relevance of rosacea. So, we aimed to explore and enrich the pathogenesis involved in pyroptosis‐related rosacea aggravations. In this study, we evaluated the pyroptosis‐related patterns of rosacea by consensus clustering analysis of 45 ferroptosis‐related genes (FRGs), with multiple immune cell infiltration analysis to identify the pyroptosis‐mediated immune response in rosacea using GSE65914 dataset. The co–co‐work between PRGs and WGCNA‐revealed hub genes has established using PPI network. FRG signature was highlighted in rosacea using multi‐transcriptomic and experiment analysis. Based on this, three distinct pyroptosis‐related rosacea patterns (non/moderate/high) were identified, and the notably enriched pathways have revealed through GO, KEGG and GSEA analysis, especially immune‐related pathways. Also, the XCell/MCPcount/ssGSEA/Cibersort underlined the immune‐related signalling (NK cells, Monocyte, Neutrophil, Th2 cells, Macrophage), whose hub genes were identified through WGCNA (NOD2, MYD88, STAT1, HSPA4, CXCL8). Finally, we established a pyroptosis‐immune co‐work during the rosacea aggravations. FRGs may affect the progression of rosacea by regulating the immune cell infiltrations. In all, pyroptosis with its mediated immune cell infiltration is a critical factor during the development of rosacea. [ABSTRACT FROM AUTHOR]

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Creating 3D‐engineered macroscopic architectures while inheriting the superior properties of individual building blocks remains one of the fundamental challenges in nanotechnology. Stable covalent interconnection between micro/nanoblocks is a desired but underexplored strategy to meet the challenges, rather than current dependently‐used weak physical forces or organic cross‐linking, which disrupts the continuity of chemical composition and electrical properties. Herein, a novel layer‐by‐layer covalent growth protocol is developed to construct all‐graphene macrostructures (AGM) with micro‐to‐macro inheritable electrical properties by laser‐assisted covalent linkage of polyethersulfone‐derived 3D porous graphene microblocks without introducing any catalysts, templates, and additives. Creatively, along with graphene generation and inter‐layer bonding, a quality optimization process is integrated into one‐step laser irradiation, which is unique and efficient for synthesizing high‐crystalline graphene. With the covalently nondestructive bridge and free of non‐graphene foreign phase impurities, AGM shows unprecedented electrical conductivity, especially a more than 100‐fold improvement in cross‐layer conductivity compared with non‐covalent assembly. Furthermore, the covalent growth mechanism of AGM is clarified by molecular dynamics simulations. Finally, the application efficacy of AGM with enhanced isotropic conductivity is verified by using it as a supercapacitor electrode. This methodology enables the as‐obtained AGM to possess the potential for high‐performance‐pursuing, multi‐disciplinary, or large‐scale applications. [ABSTRACT FROM AUTHOR]

We still lack a mechanistic understanding of why soil carbon sequestration responds distinctly to cordgrass invasion in different coastal habitats. Rapid invasion of this alien species puts carbon-rich mangroves at a risk of carbon loss by promoting the decomposition of belowground soil organic matter. [Extracted from the article]

BACKGROUOND: Grain chalkiness lowers the market value of rice. Alleviating grain chalkiness is the most challenging issue in many rice‐producing areas of the world. Nitrogen (N) metabolism has received increasing attention as a result of its relationship with grain chalkiness, although little information is available on the mechanism of N‐induced grain chalk. RESULTS: A highly chalky rice variety OM052 was used to explore the protein synthesis and its accumulation in the grain exposed to N topdressing (N+) at the panicle initiation stage and a control (N–). The results showed that chalky kernels were stimulated by the N+ treatment and more prone to occur on the top and primary rachis. The grain protein content was increased because of the increased average and maximum rates of protein accumulation during grain filling, which was related to the enhanced activities of glutamine synthetase, glutamate synthase, glutamic oxalo‐acetic transaminase and glutamate pyruvate transaminase under the N+ treatment. The activities of these enzymes at 15 days after flowering (DAF) were notably positively correlated with grain chalky traits and protein content. CONCLUSION: N topdressing regulates the synthesis and accumulation of the protein by affecting the key enzymes, especially at 15 DAF, which is attributed to grain chalkiness in rice. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The effects of global warming on crop production have received great attention in recent years. However, inconsistent results have been obtained with regard to major crops such as rice and wheat in rice–wheat rotation systems of China. Therefore, we undertook a comprehensive meta‐analysis of literature data. The yield response to warming differed for rice and wheat in the rice–wheat rotation system. Overall, warming significantly increased wheat yield (by 4.8%) but significantly reduced rice yield (by 14.8%). A number of factors were responsible for these observations. For example, rice yield responses varied with the temperature increase, variety and nitrogen (N) rate. Of these, N was the most important variable influencing yield responses to warming. The yield loss for rice was lower at temperature increases of 0.40–1.40°C and at a high N rate than that at temperature increases of 1.60–2.49°C and at a low N rate, respectively. The yield loss of indica rice was lower than that of japonica rice. For wheat, however, yield responses to warming varied with the warming regime, ambient temperature, temperature increases, and CO2 concentrations. Of these factors, ambient temperature was the most important variable influencing yield in response to warming. Warming increased wheat yield at a mean growth season temperature ≤10°C, temperature increases of 0.80–1.50°C, and at ambient CO2 concentrations. In addition, either daytime warming or nighttime warming significantly increased wheat yield. However, all‐day warming had no effect on wheat yields. We conclude that global warming will benefit wheat production but result in a serious loss of rice yield in rice–wheat rotations in China. [ABSTRACT FROM AUTHOR]

Feeding strip into continuous casting mold is a technique that can reduce the central segregation and increase the equiaxed zone ratio of continuous casting slab. Over the past decades, some steel mills have gradually applied this technique, but it still lacks a comprehensive understanding of the control theory of process parameters. Many parameters joint the influence of the steel strip melting process and strip feeding ratio, deciding the inner quality of the slab eventually. Herein, the mechanism and heat transfer of feeding strip technology are analyzed. Parameter sensitivity studies and feeding strip experiments are summarized and some new conclusions are proposed. Finally, some suggestions for industrial production will give an outlook for future work. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) contain specific proteins, lipids, and nucleic acids that can be passed to other cells as signal molecules to alter their function. However, there are many problems and challenges in the conversion and clinical application of EVs. Storage and protection of EVs is one of the issues that need further research. To adapt to potential clinical applications, this type of problem must be solved. This review summarizes the storage practices of EVs in recent years, and explains the impact of temperature on the quality and stability of EVs during storage based on current research, and explains the potential mechanisms involved in this effect as much as possible. [ABSTRACT FROM AUTHOR]

BACKGROUND: Removing excessive naturally occurring fluoride from tea and/or infusions is difficult because the process has low efficiency and causes secondary pollution. In this study, a novel electrodialysis (ED) technology was developed. We examined the effect of crucial parameters (electrolyte concentration, operation voltage, ED duration and initial concentration of the tea infusion) on defluoridation performance using a highly efficient ion‐exchange membrane with five‐compartment cells. RESULTS: The most effective ED system results were obtained at an electrolyte concentration of 10 g kg−1 and operating voltage of 20 V. Moreover, the fluoride removal capacity (10.70–66.93%) was highly dependent on the ED duration (1–15 min) and initial concentration of the tea infusion (0.5–10 g kg−1). The longer the ED duration and the lower the initial concentration, the higher was the defluoridation performance. During ED, limited loss of the main inclusions (total polyphenols, catechins, caffeine and selected ions) was observed. Furthermore, the D201 anion resin‐filled ED stack (0.5–5 g) and improvement of concentrate compartment electrolyte (≥5 times the dilute compartment electrolyte) in the ED system enhanced the defluoridation rate significantly. CONCLUSION: ED is a potentially effective method that can be used for defluoridation in the deep processing of tea products. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Introduction: Noise oversensing encountered in patients with Abbott Tendril leads in our hospital triggered an internal investigation. Methods: We retrospectively analyzed patients with a Tendril lead model 1688, 1788, 1888, and 2088. Most leads were connected to Abbott generators. To exclude a primary generator issue as the cause of noise oversensing, we enrolled a cohort of patients in whom Medtronic CapSureFix leads model 4076 and 5076 were prospectively connected to similar Abbott generators. Results: A total of 1063 Tendril leads were implanted in 869 patients. Noise was encountered in 66 leads (6.2%) during a follow‐up of 3.9 years. Most affected leads had normal impedance and only a few of these patients were symptomatic. Reprogramming was attempted in 44 of 66 (67%), and reduced oversensing in 34 of 44 (77%) of these patients. Seventeen malfunctioning leads (1.5%) were replaced, including 16 of 66 (24%) of those with noise. Of the four leads with noise extracted and returned to the manufacturer, lead to device abrasion was identified in two and inner insulation breach in one. None of the 145 Medtronic CapSureFix leads connected to Abbott generators had noise during a follow‐up of 3.6 years. Conclusion: Noise oversensing was relatively common in Tendril leads, but was not detected in Medtronic leads despite connecting to Abbott generators. Although the majority of the affected leads did not show abnormal impedance, outer or inner insulation breach was identified in three of the four returned leads. As patients with affected leads are generally asymptomatic, most of them can be managed conservatively. [ABSTRACT FROM AUTHOR]

Background Occupational health and safety (OHS) self-auditing is a common practice in industrial workplaces. However, few audit instruments have been tested for inter-rater reliability and accuracy. Methods A lockout/tagout (LOTO) self-audit checklist was developed for use in manufacturing enterprises. It was tested for inter-rater reliability and accuracy using responses of business self-auditors and external auditors. Results Inter-rater reliability at ten businesses was excellent ( κ = 0.84). Business self-auditors had high (100%) accuracy in identifying elements of LOTO practice that were present as well those that were absent (81% accuracy). Reliability and accuracy increased further when problematic checklist questions were removed from the analysis. Conclusions Results indicate that the LOTO self-audit checklist would be useful in manufacturing firms' efforts to assess and improve their LOTO programs. In addition, a reliable self-audit instrument removes the need for external auditors to visit worksites, thereby expanding capacity for outreach and intervention while minimizing costs. [ABSTRACT FROM AUTHOR]

Background Metal fabrication workers are at high risk for machine-related injury. Apart from amputations, data on factors contributing to this problem are generally absent. Methods Narrative text analysis was performed on workers' compensation claims in order to identify machine-related injuries and determine work tasks involved. Data were further evaluated on the basis of cost per claim, nature of injury, and part of body. Results From an initial set of 4,268 claims, 1,053 were classified as machine-related. Frequently identified tasks included machine operation (31%), workpiece handling (20%), setup/adjustment (15%), and removing chips (12%). Lacerations to finger(s), hand, or thumb comprised 38% of machine-related injuries; foreign body in the eye accounted for 20%. Amputations were relatively rare but had highest costs per claim (mean $21,059; median $11,998). Conclusions Despite limitations, workers' compensation data were useful in characterizing machine-related injuries. Improving the quality of data collected by insurers would enhance occupational injury surveillance and prevention efforts. Am. J. Ind. Med. 59:656-664, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT A mechanically flexible mat consisting of structurally amorphous SiO2 (glass) nanofibers was first prepared by electrospinning followed by pyrolysis under optimized conditions and procedures. Thereafter, two types of hybrid multi-scale epoxy composites were fabricated via the technique of vacuum assisted resin transfer molding. For the first type of composites, six layers of conventional glass microfiber (GF) fabrics were infused with the epoxy resin containing shortened electrospun glass nanofibers (S-EGNFs). For the second type of composites, five layers of electrospun glass nanofiber mats (EGNF-mats) were sandwiched between six layers of conventional GF fabrics followed by the infusion of neat epoxy resin. For comparison, the (conventional) epoxy composites with six layers of GF fabrics alone were also fabricated as the control sample. Incorporation of EGNFs (i.e., S-EGNFs and EGNF-mats) into GF/epoxy composites led to significant improvements in mechanical properties, while the EGNF-mats outperformed S-EGNFs in the reinforcement of resin-rich interlaminar regions. The composites reinforced with EGNF-mats exhibited the highest mechanical properties overall; specifically, the impact absorption energy, interlaminar shear strength, flexural strength, flexural modulus, and work of fracture were (1097.3 ± 48.5) J/m, (42.2 ± 1.4) MPa, (387.1 ± 9.9) MPa, (12.9 ± 1.3) GPa, and (30.6 ± 1.8) kJ/m2, corresponding to increases of 34.6%, 104.8%, 65.4%, 33.0%, and 56.1% compared to the control sample. This study suggests that EGNFs (particularly flexible EGNF-mats) would be an innovative type of nanoscale reinforcement for the development of high-performance structural composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42731. [ABSTRACT FROM AUTHOR]

Background Small manufacturing businesses often lack important safety programs. Many reasons have been set forth on why this has remained a persistent problem. Methods The National Machine Guarding Program (NMGP) was a nationwide intervention conducted in partnership with two workers' compensation insurers. Insurance safety consultants collected baseline data in 221 business using a 33-question safety management audit. Audits were completed during an interview with the business owner or manager. Results Most measures of safety management improved with an increasing number of employees. This trend was particularly strong for lockout/tagout. However, size was only significant for businesses without a safety committee. Establishments with a safety committee scored higher (55% vs. 36%) on the safety management audit compared with those lacking a committee ( P < 0.0001). Conclusions Critical safety management programs were frequently absent. A safety committee appears to be a more important factor than business size in accounting for differences in outcome measures. Am. J. Ind. Med. 58:1184-1193, 2015. © 2015 The Authors. American Journal of Industrial Medicine Published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background Metal fabrication workers experience high rates of traumatic occupational injuries. Machine operators in particular face high risks, often stemming from the absence or improper use of machine safeguarding or the failure to implement lockout procedures. Methods The National Machine Guarding Program (NMGP) was a translational research initiative implemented in conjunction with two workers' compensation insures. Insurance safety consultants trained in machine guarding used standardized checklists to conduct a baseline inspection of machine-related hazards in 221 business. Results Safeguards at the point of operation were missing or inadequate on 33% of machines. Safeguards for other mechanical hazards were missing on 28% of machines. Older machines were both widely used and less likely than newer machines to be properly guarded. Lockout/tagout procedures were posted at only 9% of machine workstations. Conclusions The NMGP demonstrates a need for improvement in many aspects of machine safety and lockout in small metal fabrication businesses. Am. J. Ind. Med. 58:1174-1183, 2015. © 2015 The Authors. American Journal of Industrial Medicine published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background Collision repair employs approximately 205,500 people in 33,400 shops. Workers are exposed to a diverse array of chemical, physical, and ergonomic hazards. Methods CARSS was based on a random and purposeful sample. Baseline and one baseline and one-year evaluations consisted of 92 questions addressing issues, such as Right-to-Know, fire protection, painting-related hazards, ergonomics, electrical safety, and personal protective equipment. Owners received a report and selected at least 30% of items found deficient for remediation. In-person and web-based services were provided. Results Forty-nine shops were evaluated at baseline and 45 at follow-up. At baseline, 54% of items were present. This improved to 71% at follow-up ( P < 0.0001). Respiratory protection improved 37% ( P < 0.0001) and Right-to-Know training increased 30% ( P < 0.0001). Owners completed 61% of items they selected for remediation. Conclusions Small businesses' interventions should address the lack of personnel and administrative infrastructure. Tailored information regarding hazards and easy-to-use training and administrative programs overcome many barriers to improvement. Am. J. Ind. Med. 58:88-100, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

To explore the clinical relevance of three lymphocyte-related serum microRNAs (miR-155, miR-214, and miR-326) to the pathogenesis of graft-versus-host disease (GVHD), 64 subjects who received allogeneic peripheral blood stem cell transplantation (allo-PBSCT) were recruited in this study, of whom 19 subjects did not develop GVHD, 25 subjects were diagnosed with acute GVHD ( aGVHD), and 20 subjects were diagnosed with chronic GVHD ( cGVHD). Serum miRNAs were determined by real-time RT-PCR. Expression level of miRNAs and the expression signatures of miRNAs as a panel were analyzed among the three groups. The expression level of miR-214 and miR-326 showed no significant difference between GVHD and non-GVHD groups. However, miR-155 was significantly up-regulated in GVHD patients. There was a correlation between the level of miR-155 and the severity of aGVHD. Moreover, serum IFN-gamma, IL-17, and IL-9 levels were higher in aGVHD patients with high miR-155. In conclusion, the expression level of lymphocyte-related miR-155 in serum was significantly increased in aGVHD patients. The miR-155 may be considered as a potential targeted therapy for aGVHD patients. [ABSTRACT FROM AUTHOR]

Background In the United States, approximately 236,000 people work in 37,600 auto collision-repair businesses. Workers in the collision-repair industry may be exposed to a wide range of physical and chemical hazards. Methods This manuscript examines the relationship of safety climate as reported by collision repair shop workers and owners to: (1) an independent business safety assessment, and (2) employee self-reported work practices. The study was conducted in the Twin Cities metropolitan area. Results A total of 199 workers from 49 collision shops completed a survey of self-reported work practices and safety climate. Surveys were completed by an owner or manager in all but three shops. In general, self-reported work practices were poor. Workers' scores on safety climate were uniformly lower than those of owners. For workers, there was no correlation between how well the business scored on an independent audit of business safety practices and the safety climate measures they reported. For owners, however, there was a positive correlation between safety climate scores and the business safety assessment. For workers, safety rules and procedures were associated with improved work practices for those engaged in both painting-related and body technician-related activities. Conclusions The enforcement of safety rules and procedures emerged as a strong factor positively affecting self-reported work practices. These findings identify a simple, cost effective path to reducing hazards in small workplaces. Am. J. Ind. Med. 57:78-86, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective Human mesenchymal stem cells (hMSCs) represent one of the most promising stem cell therapies for traumatic injury and age-related degenerative diseases involving cartilage. However, few genetic factors regulating chondrogenesis of MSCs have been identified. One study showed that zinc-finger protein 145 (ZNF145), a transcription factor, was up-regulated during 3-lineage differentiation of hMSCs. The present study was undertaken to validate whether this novel transcription factor is useful for the repair and regeneration of cartilage. Methods Human MSCs were transfected with lentiviral short hairpin RNA (for small interfering RNA knockdown of ZNF145) and a lentiviral vector for overexpression of ZNF145, and the effects of ZNF145 on chondrogenesis were studied using quantitative polymerase chain reaction and immunostaining. Microarray and transient expression analyses were used to determine whether ZNF145 is a factor operating upstream of SOX9. Allogeneic transplantation of hMSCs into osteochondral defects in rats was performed to determine the effects of ZNF145 on repair of cartilage in vivo. Results Small interfering RNA-mediated gene silencing of ZNF145 slowed down chondrogenesis, whereas overexpression of ZNF145 enhanced chondrogenesis. Global gene expression profiling showed up-regulated gene expression in ZNF145-overexpressing MSCs, and transient overexpression of ZNF145 enhanced the expression of SOX9, suggesting that ZNF145 acts as a factor upstream of SOX9, the master regulator of chondrogenesis. Moreover, allogeneic transplantation of hMSCs into osteochondral defects of rat knees showed that ZNF145-overexpressing MSCs repaired cartilage defects better and earlier than empty control MSCs. Conclusion These findings suggest that ZNF145 gene therapy may be a very useful strategy for improving the quality of cartilage regeneration and repair. [ABSTRACT FROM AUTHOR]

A slot-type split-ring resonator (SRR) as a new type of perturbation element for dual-mode square patch resonator is introduced in this article.The slot-type SRR used in the patch resonator allows coupling between the two degenerate modes. Moreover, coupling characteristics can be adjusted by the location of slot-type SRR. By adding two notches in the dual-mode filter with slot-type SRR, the high degenerate mode near the passband is eliminated, and the center frequency is lowered slightly. It has been verified by both simulation and measurement. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26148 [ABSTRACT FROM AUTHOR]

Human embryonic stem cells (hESCs) are considered as useful tools for pre-clinical studies in regenerative medicine. Although previous reports have shown direct chondrogenic differentiation of mouse and hESCs, low yield and cellular heterogenicity of the resulting cell population impairs the generation of sufficient numbers of differentiated cells for further testing and applications. Based on our previously established high-density micromass model system to study hESC chondrogenesis, we evaluated the effects of transforming growth factor (TGF)-β1 and bone morphogenetic protein-2 on early stages of chondrogenic differentiation and commitment by hESCs. Significant chondrogenic induction of hESCs, as determined by quantitative measurements of cartilage-related gene expression and matrix protein synthesis, was achieved in the presence of TGF-β1. By means of selective growth factor combination (TGF-β1, FGF-2 and platelet-derived growth factor-bb) and plating on extracellular matrix substratum, we report here the reproducible isolation of a highly expandable, homogenous and unipotent chondrogenic cell population, TC1, from chondrogenically committed hESCs. Like primary chondrocytes, TC1 rapidly dedifferentiates upon isolation and monolayer expansion but retains the chondrogenic differentiation potential and responds to TGF-β1 for cartilaginous tissue formation both in vitro and in vivo. In addition, TC1 displays a somatic cell cycle kinetics, a normal karyotype and does not produce teratoma in vivo. Thus, TC1 may provide a potential source of chondrogenic cells for drug testing, gene therapy and cell-based therapy. [ABSTRACT FROM AUTHOR]

Our previous studies have indicated that TGF-β1 exerts its effect on the expression of A-type potassium channels (IA) in rat vascular myofibroblasts by activation of protein kinase C during the phenotypic transformation of vascular fibroblasts to myofibroblasts. In the present study, patch-clamp whole-cell recording and transwell-migration assays were used to examine the effects of TGF-β1- and phorbol 12-myristate 13-acetate (PMA)-induced expression of IA channels on myofibroblast migration and its modulation by the protein kinase A (PKA) pathway. Our results reveal that incubation of fibroblasts with TGF-β1 or PMA up-regulates the expression of IA channels and increases myofibroblast migration. Blocking IA channel expression by 4-aminopyridine (4-AP) significantly inhibits TGF-β1- and PMA-induced myofibroblast migration. Incubation of fibroblasts with forskolin does not result in increased expression of IA channels but does cause a slight increase in fibroblast migration at higher concentrations. In addition, forskolin increases the TGF-β1- and PMA-induced myofibroblast migration but inhibits TGF-β1- and PMA-induced the expression of IA channels. Whole-cell current recordings showed that forskolin augments the delayed rectifier outward K+ (IK) current amplitude of fibroblasts, but not the IA of myofibroblasts. Our results also indicate that TGF-β1- and PMA-induced expression of IA channels might be related to increase TGF-β1- or PMA-induced myofibroblast migration. Promoting fibroblast and myofibroblast migration via the PKA pathway does not seem to involve the expression of IA channels, but the modulation of IK and IA channels might be implicated. J. Cell. Physiol. 216: 835–843, 2008, © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Previously, we reported that apoptosis of cerebellar granular neurons induced by low-K+ and serum-free (LK-S) was associated with an increase in the A-type K+ channel current ( IA), and an elevated expression of main α-subunit of the IA channel, which is known as Kv4.2 and Kv4.3. Here, we show, as assessed by quantitative RT-PCR and whole-cell recording, that besides Kv4.2 and Kv4.3, Kv1.1 is very important for IA channel. The expression of Kv1.1 was elevated in the apoptotic neurons, while silencing Kv1.1 expression by siRNA reduced the IA amplitude of the apoptotic neuron, and increased neuron viability. Inhibiting Kv1.1 current by dendrotoxin-K evoked a similar effect of reduction of IA amplitude and protection of neurons. Applying a protein kinase C (PKC) activator, phorbol ester acetate A (PMA) mimicked the LK-S-induced neuronal apoptotic effect, enhanced the IA amplitude and reduced the granule cell viability. The PKC inhibitor, bisindolylmaleimide I and Gö6976 protected the cell against apoptosis induced by LK-S. After silencing the Kv1.1 gene, the effect of PMA on the residual K+ current was reduced significantly. Quantitative RT-PCR and Western immunoblot techniques revealed that LK-S treatment and PMA increased the level of the expression of Kv1.1, in contrast, bisindolylmaleimide I inhibited Kv1.1 expression. In addition, the activation of the PKC isoform was identified in apoptotic neurons. We thus conclude that in the rat cerebellar granule cell, the IA channel associated with apoptotic neurons is encoded mainly by the Kv1.1 gene, and that the PKC pathway promotes neuronal apoptosis by a brief modulation of the IA amplitude and a permanent increase in the levels of expression of the Kv1.1 α-subunit. [ABSTRACT FROM AUTHOR]

The present study aimed to describe the disease progression of chronic hepatitis B patients without or with compensated cirrhosis at baseline, to estimate the risk of progression to decompensated cirrhosis, hepatocellular carcinoma and death, and to determine prognostic factors of disease progression in patients in Shanghai, China. Stored medical records from 322 biopsy-confirmed chronic hepatitis B cases diagnosed between 1981 and 1993 were selected, and the status of patients was tracked in 1999–2000. Among consenting patients, ultrasound examination and laboratory tests were conducted. Person-year incidence rates, Kaplan–Meier analysis, log-rank tests, and Cox regression analysis were conducted. Among chronic hepatitis B patients without compensated cirrhosis, the incidence rates of decompensated cirrhosis, hepatocellular carcinoma, and death were 6.3, 2.8, and 7.6 per 1000 person-years, respectively, while for patients with compensated cirrhosis, the rates were 35.6, 8.2, and 35.2 per 1000 person-years, respectively. The 15-year survival rate was 88% for patients without compensated cirrhosis, compared with 56% for patients with compensated cirrhosis ( P < 0.001). Cox regression analysis demonstrated that increased α-fetoprotein (AFP) ( P < 0.01), γ-globulin ( P < 0.05), and high-level severity of hepatic fibrosis ( P < 0.01) at baseline were risk factors of decompensated cirrhosis. Factors associated with a high risk of death included elevated AFP at baseline ( P < 0.01), severity of hepatic fibrosis ( P < 0.003), and sustained positivity for hepatitis B surface antigen ( P < 0.004). Increased AFP and severity of hepatic fibrosis at baseline were associated with higher risk of decompensated cirrhosis and death. These data provide rare empirical estimates of the negative long-term outcomes for patients with chronic hepatitis B in Shanghai, China. [ABSTRACT FROM AUTHOR]

A half‐mode substrate integrated waveguide (HMSIW) omnidirectional slot antenna is proposed for the first time by integrating four narrow wall radiating slot antenna elements and a four‐way power divider. The slot antenna element realises energy radiation from the open side of the HMSIW by etching several pairs of transversal slots both on the upper and the lower surfaces of the HMSIW and alternately arranging the slot pairs. A novel HMSIW four‐way power divider is achieved to feed the slot antenna elements by loading four big metallic vias to guide the microwave into the HMSIW branches. This omnidirectional slot antenna has an efficiency of 86%, a gain of 5.8 dBi and an out‐of‐roundness of ±1.5 dB at 3 GHz, which makes it a good candidate for wireless communication applications. [ABSTRACT FROM AUTHOR]

A compact microstrip dual-plane resonant cell structure is presented. Good lowpass performance and wide stopband characteristics can be obtained with a simple single resonant cell; multiple resonant modes are introduced in the stopband, thus rejection width is significantly improved. Measured results of the fabricated prototype show that the stopband bandwidth better than -20 dB is more than 13 GHz, but its occupied area is only 20 × 30 mm2. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1776–1778, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25357 [ABSTRACT FROM AUTHOR]

A novel compact microstrip low-pass filter (LPF) with ultra-wide stopband, low insertion loss, and sharp cutoff is introduced in this letter. The LPF is composed of a stepped-impedance hairpin resonator, a square split-ring resonator, defected ground structure (DGS), and a pair of coupled DGSs with compensated microstrip lines. Measured results show that the 10-dB stopband is up to 19.62 GHz, passband loss is below 0.5 dB, and the selectivity of the filter is more than 180 dB/GHz, but its occupied area is only 20 × 35 mm2. It can be widely used for higher harmonics suppression for wideband microwave applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 568–570, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24976 [ABSTRACT FROM AUTHOR]

Although physical exercise has been recommended as a useful means of enhancing the mental health of adolescents, the exact mechanisms through which physical exercise plays a role are unclear. Both physical exercise and mental health are complex concepts with multiple facets, and traditional methods may constrain the manifestations of their mapping relationships. This research aimed to find the bridging connections between physical exercise and mental health. Mental health and physical exercise behaviors were assessed using the Symptom Checklist 90 (SCL‐90) and the Adolescent Physical Activity Questionnaire (PAQ‐A) in 9072 Chinese adolescents, respectively. Network analysis was utilized to construct the mental health‐physical exercise network and to analyze the relationships between individual physical exercise behaviors and mental health symptoms. Core and bridging nodes were identified based on expected influence (EI) and bridge expected influence (BEI). Gender differences were also examined. The results revealed specific and distinct pathways between physical exercise and mental health (e.g., winter sports–obsessive‐compulsive symptoms, winter sports–phobia). For both males and females, anxiety, depression, interpersonal sensitivity, ball sports, and evening activity were the most central symptoms/behaviors, reflecting their relative significance in their respective associations. The nodes with the highest BEI were obsessive‐compulsive symptoms and physical education, showing negative associations with nodes in the other community. Furthermore, in the male group, somatization and winter sports stood out as the most positive bridge nodes. Conversely, in the female group, interpersonal sensitivity and sports games were the most positive bridge nodes. These findings illuminate the pathways linking physical exercise and mental health, supporting the implementation of physical exercise in a more elaborate way. [ABSTRACT FROM AUTHOR]

A half-mode substrate integrated waveguide (HMSIW) omnidirectional slot antenna is proposed for the first time by integrating four narrow wall radiating slot antenna elements and a four-way power divider. The slot antenna element realises energy radiation from the open side of the HMSIW by etching several pairs of transversal slots both on the upper and the lower surfaces of the HMSIWand alternately arranging the slot pairs. A novel HMSIW four-way power divider is achieved to feed the slot antenna elements by loading four big metallic vias to guide the microwave into the HMSIW branches. This omnidirectional slot antenna has an efficiency of 86%, a gain of 5.8 dBi and an out-of-roundness of ±1.5 dB at 3 GHz, which makes it a good candidate for wireless communication applications. [ABSTRACT FROM AUTHOR]

Chemical equations are presented for the article "Environmentally Friendly Approach to Convergent Synthesis of Highly Functionalized Indanone Fused Multicyclic Pyrrolines" by X.-M. Liu and colleagues, published in the periodical "Tetrahedron."

A novel compact miniaturized stepped impedance low-pass filter using an improved split ring resonator defected ground structure is proposed. This filter has the advantages of compact size, easy fabrication. When compared with conventional SIR, it has a sharp cutoff characteristic with low insertion loss. It is quite useful for common planar circuits and devices. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2257–2258, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24619 [ABSTRACT FROM AUTHOR]

Human embryonic stem cells (hESCs) are considered as useful tools for pre-clinical studies in regenerative medicine. Although previous reports have shown direct chondrogenic differentiation of mouse and hESCs, low yield and cellular heterogenicity of the resulting cell population impairs the generation of sufficient numbers of differentiated cells for further testing and applications. Based on our previously established high-density micromass model system to study hESC chondrogenesis, we evaluated the effects of transforming growth factor (TGF)-beta(1) and bone morphogenetic protein-2 on early stages of chondrogenic differentiation and commitment by hESCs. Significant chondrogenic induction of hESCs, as determined by quantitative measurements of cartilage-related gene expression and matrix protein synthesis, was achieved in the presence of TGF-beta(1). By means of selective growth factor combination (TGF-beta(1), FGF-2 and platelet-derived growth factor-bb) and plating on extracellular matrix substratum, we report here the reproducible isolation of a highly expandable, homogenous and unipotent chondrogenic cell population, TC1, from chondrogenically committed hESCs. Like primary chondrocytes, TC1 rapidly dedifferentiates upon isolation and monolayer expansion but retains the chondrogenic differentiation potential and responds to TGF-beta(1) for cartilaginous tissue formation both in vitro and in vivo. In addition, TC1 displays a somatic cell cycle kinetics, a normal karyotype and does not produce teratoma in vivo. Thus, TC1 may provide a potential source of chondrogenic cells for drug testing, gene therapy and cell-based therapy.

Background: Problems of improving safety in small business establishments may include a lack of resources, limited unionization, and an informal management structure., Methods: We evaluated worker and manager perceptions of worksite health and safety using Social Cognitive Theory. We used a business safety scorecard to audit the safety conditions, policies and programs, and work practices. Comparisons were made between the different measures., Results: Businesses with safety committees had 1.7-2.1 times higher proportion of positive safety scorecard items than businesses without committees. Union status and business size were not associated with business safety audit results. Non-English-speaking and less educated employees reported higher levels of knowledge about safety than did their more educated and/or English-speaking peers., Conclusions: The presence of a safety committee is the single most important indicator of workplace safety. Self-reported understanding of workplace safety is greater among employees who do not speak English or have lower levels of formal education. Future worksite interventions should consider the need for participatory worksite safety committees. Multilingual training programs would help reach a greater proportion of workers.

Background: Metal working has been identified as an industry with one of the highest rates of non-fatal injury in the United States. However, the systematic evaluation of machine-related hazards is lacking., Methods: The Minnesota Machine Guarding Study evaluates the effectiveness of a peer-based technical and educational intervention designed to reduce exposure to amputation hazards among workers in small machining/metal working businesses. The data presented here provide a profile of machine guarding in small (5-100 employees) metal fabrication businesses in Minnesota. A set of checklists to quantify machine-guarding practices were developed. Up to 25 randomly selected machines were evaluated in each facility. In addition, walk-through surveys were conducted to assess machine-related safety practices and programs (e.g., lock out-tag out)., Results: A total of 824 machines were evaluated. Overall, 55% (SD 11%) of items addressing machine guarding were present. No single machine complied with all critical safety requirements. Shops with safety committees tended to have better scores than did shops without safety committees. Thirty-five percent of all businesses had established machine guarding procedures and 17% provided training in machine guarding (e.g., use of machine guards and devices in daily operations) to their employees., Conclusions: These data indicate that machine guarding and related safety programs in small metal fabrication businesses were inadequate. The data also suggest that safety committees are an important component in improving machine safety and related programs in small businesses., (Copyright 2006 Wiley-Liss, Inc.)

Background: Each year there are an estimated 4.2-6.7 amputations per 10,000 workers in the metal fabrication trades in the United States. The Minnesota Machine Guarding Study evaluates the effectiveness of a peer-based technical and educational intervention designed to reduce exposure to amputation hazards among workers in small machining/metal working shops. The study reported here involved the development and evaluation of methods for measuring machine safety, which will be used in the intervention study., Methods: Using OSHA regulations, ANSI standards, and industry best practices, we developed 23 machine-safety scorecards. The safety scores were dependent on the presence or absence of guards, other safety devices and implements, and the presence or absence of acceptable administrative programs. Inter-rater reliability was assessed for the evaluation of eight types of commonly used metal fabrication machines., Results: Of the 23 most common types of machines, there were a sufficient number of machines to evaluate inter-rater reliability for eight types. Three raters in four shops assessed fifty-nine machines. Overall, the kappa statistic ranged from 0.57 to 0.84, indicating good to very good concordance between raters. In general, machines did not fare well with regard to compliance with current standards., Discussion: The ability to assess machine-related hazards is important in industries where it is difficult to identify and count injuries in a timely fashion. Machinists and safety professionals may use this scoring system as a means of reproducible assessment of machine safety.