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• The expression of Ski in reactive astrocytes was increased in a time dependent manner. • OGD/R can induce the activation and inflammation of astrocytes. • Ski regulates inflammatory response of reactive astrocytes by regulating NF-κB pathway. • Ski silencing can inhibit the expression of NF-κB pathway, thereby inhibiting the activation of astrocytes and the release of inflammatory factors. • Ski is a promising therapeutic target for the inflammatory response after CNS ischemia injury. Spinal cord injury (SCI) is a common disease of the nervous system, including primary and secondary injuries. Neuronal inflammation after SCI is the most important pathological process of SCI and a chemical barrier to nerve function recovery after injury. Ski, an evolutionarily conserved functional transcriptional regulator protein, is upregulated in reactive astrocytes after SCI and regulates the biological characteristics of astrocytes. However, its role in the glial inflammatory response triggered by reactive astrocytes after spinal cord ischemia and its exact mechanism remains unclear. This study investigated the role and mechanism of Ski in the inflammatory response triggered by reactive astrocytes induced by oxygen and sugar deprivation/reoxygenation (OGD/R) model in vitro. In the ODG/R model, Ski expression was upregulated. In contrast, Ski upregulation was accompanied by increased levels of iNOS, IL-1β, IL-6, TNF-α, and other inflammation-related factors. These results indicated that the inflammatory response triggered by astrocytes was significantly enhanced in OGD/R-stimulated astrocytes. Astrocytes were transfected with Ski specific siRNA to knock out Ski and subsequently attenuate OGD-induced astrocyte-triggered inflammation. Our results also suggest that Ski downregulation downregulates the expression of iNOS, IL-1β, IL-6, and TNF-α in OGD/R-induced reactive astrocytes by inhibiting the activity of the NF-κB signaling pathway. In conclusion, downregulation of Ski can effectively inhibit glial inflammation in SCI by inhibiting the activity of the NF-κB pathway. These findings suggest that Ski is a promising therapeutic target for inflammatory responses after SCI. In conclusion, Ski downregulation can effectively inhibit glial inflammation in SCI by inhibiting the activity of the NF-κB pathway. These findings suggest that Ski might serve as a promising target for the treatment of inflammatory responses after SCI. [ABSTRACT FROM AUTHOR]

• The proliferation of reactive astrocytes is involved in the whole process of spinal cord injury. • The proliferation of astrocytes regulated by Ski mediated by SP2 was studied in vitro. • Verify the hypothesis by using bioinformatics, WB, RT-PCR, immunofluorescence, flow cytometry, and other tests. • The transcription factor SP2 mediates astrocyte proliferation by specifically binding the Ski promoter region to regulate its. • This finding may lead to new targets for therapeutic treatments after SCI. Transcription factors bind specific sequences upstream of the 5′ end of their target genes to ensure proper spatiotemporal expression of the target gene. This study aims to demonstrate that the transcription factor SP2 regulates expression of the Ski gene, which has specific binding sites for SP2, and thus enables Ski to regulate astrocyte proliferation. The upstream regulation mechanism of astrocyte proliferation was explored to further regulate the formation of glial scar in specific time and space after spinal cord injury. JASPAR and UCSC databases were used to predict transcription factor binding and the threshold was gradually reduced to screen transcription factors upstream of Ski, leading to the identification of SP2. Next, we analyzed the correlation between the expression of SP2 and Ski in normal astrocytes and reactive astrocytes, as well as the changes in astrocyte proliferation. To confirm that SP2 regulates Ski during astrocyte proliferation, astrocytes were transfected siRNA targeting SP2 and then astrocyte proliferation were analyzed. Finally, a dual luciferase reporter assay and Chromatin immunoprecipitation (ChIP) assay confirmed that the promoter region of Ski contained a specific SP2 binding site. This is the first that SP2 has been identified and confirmed to play an important role in astrocyte proliferation by regulating Ski expression. These results may help identify novel targets for the treatment of spinal cord injury. [ABSTRACT FROM AUTHOR]

Introduction: Sport helmet effectiveness in preventing traumatic brain injury (TBI) has been repeatedly questioned. This study assesses the effect of helmet use on risk of TBI and other types of head injury (OTHI) in alpine sports.Methods: From 2012 to 2014, data on the injured population were collected by physicians in on-mountain clinics in 30 French ski resorts, and interviews were conducted on the slope to sample a noninjured control population. Two sets of cases (1425 participants with TBI and 1386 with OTHI) were compared with 2 sets of controls (2145 participants without injury and 40,288 with an injury to a body part other than the head). The effect of helmet use on the risk of TBI and OTHI was evaluated with a multivariate logistic regression adjusted for age, sex, sport, skill level, crash type, and crash location.Results: Using participants without injury as control, we found that helmet wearers were less likely to sustain any head injury (odds ratio [OR]TBI = 0.65; OROTHI = 0.42). When considering participants with an injury to another body part as control, the risk of OTHI was lower among helmet wearers (OROTHI: 0.61). However, no significant effect was found for the risk of TBI. Participants with low skill levels, those aged <26 and >50 years, snowboarders, and those involved in collision and in snowpark accidents were at higher risk of head injury.Conclusions: This study confirms the effectiveness of helmets in protecting users from head injuries but questions their effects on TBI, especially concussion. [ABSTRACT FROM AUTHOR]

Purpose Skiing and snowboarding are popular winter sports. The purpose of this study was to determine differences in injury patterns and severity between children participating in these sports treated at trauma centers in the United States. Methods Ski and snowboard injuries in children < 15 identified from the 2011–2015 National Trauma Data Bank were compared using t tests, chi squared tests, and multivariable analyses. Time trends were evaluated using the Cochran Armitage trend test. Results We identified 1613 injured snowboarders and 1655 skiers. Snowboarders were older (12 vs. 11 years, p < .001) and more likely to be male (84 vs. 68%, p < .001). The proportion of ski to snowboard injuries increased over time (p < .001). Skiers had greater median ISS than snowboarders (5 vs. 4, p < .001) but similar severe injuries ISS ≥ 16 (9 vs. 8%, p = .31). Head injuries were more frequent among snowboarders (26 vs. 23%, p = .013). Helmet use was greater in skiers (46 vs. 34%, p < .001). Skiers were more likely to sustain face, chest, and lower extremity injuries. Snowboarders had more abdominal and upper extremity injuries (p < .05). Snowboarders were more likely to undergo CT (20 vs. 16%, p = .008), and skiers were more likely to undergo surgery (25 vs. 22% p = .021). Need for intensive care (12 vs. 13%, p = .43) and mortality (0.3 vs. 0.3%, p = .75) were similar. Median length of stay was greater for skiers (2 days vs. 1 day, p < .001). Conclusion Many children are treated at United States trauma centers for ski and snowboard injuries. One in 10 is severely injured. Different injury patterns between sports can be used to tailor prevention efforts. However, avoiding head injury and improving helmet use should be a priority for all children on the slopes. Level of Evidence III Type of study Prognostic [ABSTRACT FROM AUTHOR]

The relationship between methylation abnormality and autoimmune pancreatitis (AIP)—a representative IgG4-related disease—has not yet been elucidated. We identified SKI might have a significant methylation abnormality in AIP through methylation array analysis using the Illumina Infinium Human Methylation 450K BeadChip array, and investigated the relationship of SKI with AIP clinicopathological features. The methylation rate of SKI was assessed by quantitative SYBR green methylation-specific PCR, and the degree of SKI expression in tissue specimens was assessed by immunohistochemistry in 10 AIP cases, 14 cases of obstructive pancreatitis area in pancreatic ductal adenocarcinoma (PDA) without a history of AIP, and 9 normal pancreas (NP) cases. The SKI methylation ratio was significantly lower in AIP than in PDA and NP. Additionally, the immunohistochemical staining-index (SI) score for SKI was significantly higher in AIP than NP, although there was no significant difference between AIP and PDA. There was a strong negative correlation between SI score and SKI methylation ratio, and between the serum concentrations of IgG4 and the SKI methylation ratio. There was a moderate positive correlation between the serum concentrations of IgG4 and SI. SKI is thought to be an oncogene indicating that SKI hypomethylation and carcinogenesis might be linked to AIP. Furthermore, the correlation between serum concentrations of IgG4 and SKI methylation levels suggest SKI might be involved in the pathogenesis of AIP. However, the role of SKI has not been clearly elucidated. Further studies are needed to understand further the function of SKI . [ABSTRACT FROM AUTHOR]

• Incidence of skiing and snowboarding injuries has decreased significantly over the last decades to 0.44 injuries per 1000 skier days. • The winter season of the COVID-19 outbreak had no significant influence on injury rates. • Further studies on safety measures and their efficacy should be emphasized. The incidence of injuries on alpine ski slopes have been assessed using various methods. A decline in injury rate has been observed throughout the literature; however, the actual incidence remains unclear. The purpose of this study was therefore to evaluate the incidence of skiing and snowboarding injuries using large-sample data from an entire geographic state. Data on alpine injuries over the course of five winter seasons between 2017 and 2022 were prospectively collected from the emergency service dispatch center of Tyrol (Austria). The incidence of injuries was assessed in relation to the number of skier days, which was obtained from the chamber of commerce. A total of 43,283 cases were identified, and a total of 98.1 Mio skier days were registered during the inclusion period of our study, resulting in an overall incidence of 0.44 injuries per 1,000 skier days. This is significantly less than reported from previous studies. From 2017/18 to 2021/22 there was a slight increase in injuries per 1000 skier days with an exception only for the COVID-19 related season 2020/21. Our study showed a significant reduction in the incidence of alpine skiing and snowboarding injuries in comparison with previous studies and should be considered a benchmark for future studies. Long-term studies on the efficacy of safety gear, as well as the influence of ski patrol and air-borne rescues on patient outcome are warranted. [ABSTRACT FROM AUTHOR]

Ski, as an evolutionarily conserved protein, is a versatile transcriptional regulator which widely distributes in various tissues and species. Recently, we have demonstrated for the first time that Ski was strikingly up-regulated in reactive astrocytes after spinal cord injury (SCI) in vivo , which indicates that maybe Ski is a new molecule that controls astrocytes’ biological properties after SCI. However, the accurate distributions and functions of Ski in astrocytes after central nervous system (CNS) injury are still unclear. Astrocytes were collected from rats’ cerebral cortex. To elucidate the expression and role of Ski in reactive astrocytes, we performed an activated astrocytes model induced by LPS and scratch injury in vitro . Our results showed that Ski gradually increased and reached a peak at 4 days, then declined at 6 days after induction by LPS. Up-regulation of Ski was accompanied with the increase in proliferation-related proteins including PCNA, CDK4 and CyclinD1. Furthermore, immunofluorescent staining analysis also demonstrated a highly positive relationship between Ski and GFAP, PCNA in astrocytes. These results indicated that Ski might play an important role in astrocyte proliferation. To further explore the role of Ski, astrocytes were transfected with Ski-specific small interfering RNA (siRNA). We found that the primary activated astrocytes’ proliferation decreased significantly after transfection with Ski-specific siRNA. Surprisingly, Ski knockdown also weakened the primary astrocyte migration. Based on the above, we could conclude that Ski might play a crucial role in astrocyte proliferation and migration. This discovery might contribute to a promising therapeutic intervention in CNS injury. [ABSTRACT FROM AUTHOR]

Objective: Current protocols for spine immobilization of the injured skier/snowboarder have not been scientifically validated. Observing changes in spine alignment during common rescue scenarios will help strengthen recommendations for rescue guidelines.Methods: Twenty-eight healthy volunteers (18 men, 10 women) age 47±17 (range 20-73) (mean ±SD with range) underwent a mock rescue in which candidate patrollers completing an Outdoor Emergency Care course performed spine immobilization and back boarding in 3 scenarios: 1) Ski helmet on, no c-collar; 2) helmet on, with c-collar; and 3) helmet removed, with c-collar. After each scenario, a lateral radiograph was taken of the cervical spine to observe for changes in alignment.Results: Compared with the control group (helmet on, no collar), we observed 9 degrees of increased overall (occiput-C7) cervical extension in the helmet on, with collar group (P < .001), and 17 degrees in the helmet off, with collar group (P < .001). There was increased extension at the occiput-C2 intersegment in the helmet on, with collar group (9 degrees, P < .001) and at both the occiput-C2 (9 degrees, P < .001) and C2-C7 (8 degrees, P < .001) intersegments in the helmet off, with collar group.Conclusion: Ski helmet removal and c-collar application each leads to increased extension of the cervical spine. In the absence of other clinical factors, our recommendation is that helmets should be left in place and c-collars not routinely applied during ski patrol rescue. [ABSTRACT FROM AUTHOR]

Objective Endothelial dysfunction occurs early during atherogenesis and it can be normalized by exercise training. Unfortunately, patients' compliance with exercise prescription remains low, often because the given choices do not appeal to them. In Alpine regions, skiing is a popular mode of exercise, and therefore we set out to assess whether it can induce antiatherogenic effects. Methods We randomized 42 subjects into a group of 12 weeks of guided skiing (intervention group, IG, n = 22; 12 males/10 females; age: 66.6 ± 2.1 years) or a control group (CG, n = 20; 10 males/10 females; age: 67.3 ± 4.4 years). Early (CD3 − CD34 + CD45 +) and late endothelial progenitor cells (EPCs; CD45dimCD34 + KDR + peripheral blood mononuclear cells, PBMCs), peripheral arterial tonometry and endothelial biomarkers were assessed at the beginning and end of the study. Results In the IG, participants completed 28.5 ± 2.6 skiing days at an average heart rate of 72.7 ± 8.5% of their maximum heart rate. Changes in early (IG: + 0.001 ± 0.001% PBMC; CG: − 0.001 ± 0.001% PBMC; IG vs. CG: p < 0.001) but not late EPCs differed significantly. Changes in peripheral arterial tone differed significantly between IG (Reactive Hyperemia Index: + 0.18 ± 0.76) and CG (− 0.39 ± 0.85; p = 0.045), as did homocysteine (IG: − 1.3 ± 1.3 μmol/l; CG: − 0.4 ± 1.4 μmol/l; p = 0.037) while other endothelial biomarkers remained essentially unchanged. Conclusions This study shows that skiing induces several beneficial effects on markers of atherogenesis including EPCs, peripheral arterial tone and homocysteine. Our findings suggest that recreational alpine skiing may serve as a further mode of preventive exercise training, which might result in improved compliance with current recommendations. [ABSTRACT FROM AUTHOR]

Inappropriate cardiac interstitial remodeling is mediated by activated phenoconverted myofibroblasts. The synthesis of matrix proteins by these cells is triggered by both chemical and mechanical stimuli. Ski is a repressor of TGFβ 1 /Smad signaling and has been described as possessing anti-fibrotic properties within the myocardium. We hypothesized that overexpression of Ski in myofibroblasts will induce an apoptotic response, which may either be supported or opposed by autophagic flux. We used primary myofibroblasts (activated fibroblasts) which were sourced from whole heart preparations that were only passaged once. We found that overexpression of Ski results in distinct morphological and biochemical changes within primary cardiac myofibroblasts associated with apoptosis. Ski treatment was associated with the expression of pro-apoptotic factors such as Bax, caspase-7, and -9. Our results indicate that Ski triggers a pro-death mechanism in primary rat cardiac myofibroblasts that is mediated through the intrinsic apoptotic pathway. Myofibroblast survival is prolonged by an autophagic response, as the dataset indicate that apoptosis is hastened when autophagy is inhibited. We suggest that the apoptotic death response of myofibroblasts is working in parallel with the previously observed anti-fibrotic properties of Ski within this cell type. As myofibroblasts are the sole mediators of matrix expansion in heart failure, we suggest that Ski, or a putative Ski-mimetic, may induce graded apoptosis in myofibroblasts within the failing heart and may be a novel therapeutic approach towards controlling cardiac fibrosis. Future studies are needed to examine the potential effects of Ski overexpression on other cell types in the heart. [ABSTRACT FROM AUTHOR]

The ski manufacturing industry is characterized by short product life cycles and high innovation pressure in order to meet customer's expectations of progressive improvements of skis. To reduce development time a FE model was developed and validated to simulate the influence of changes of the ski construction on its bending and torsional stiffness. Moreover, the study aimed to evaluate the feasibility of a novel ski sandwich construction with a load dependent bending stiffness. Therefore, the FE model was used to define required strain-stiffening of a single construction layer material to reach a perceptible change of the overall ski's bending stiffness. Two existing skis with identical geometry but distinctive differences of their torsional and bending stiffness were modelled using ANSYS Workbench. The sandwich construction was modelled by 18 solid bodies with bonded contacts: core, sidewalls, edges, upper and lower face with 13 layers including 3 additional resin interlayers. Orthotropic linear elastic material properties were taken from data sheets of suppliers and from material tests of the manufacturer. Sweep meshing was used to create an all-hex mesh of solid elements. Static structural simulations of a 3-point bending test and a torsion test were run in accordance to existing laboratory tests to validate the model. For both skis, the FE model showed good agreement with the experimental data for ski A and B. The simulated overall bending stiffness (center spring constant) was, respectively 2.8% and 3.2% higher compared to the experiments. The elastic curves revealed the model as slightly too stiff at the afterbody and too soft at the forebody. The simulated torsional stiffness (torsional spring constant) was, respectively 2.1% and 4.2% lower than found in the experiments. In the development process, for example, the model was then used to quantify the influence of edge profile heights on the ski's overall bending stiffness (3% per 0.1 mm edge height). The application of strain-stiffening materials to realize a load depending ski stiffness turned as not feasible due to too small strains within the ski structure. A realistic representation of the different construction layers of an alpine ski is still challenging, especially due to the heterogeneity of the fibre compound layers and the resin distribution. Using bulk properties of the upper and lower face of the sandwich construction is not an alternative. To virtually test the influence of new materials and layups every single layer has to be represented. Using two skis for validation and additional resin interlayers for calibration appeared appropriate in order to achieve adequate model results. [ABSTRACT FROM AUTHOR]

In downhill alpine skiing, racers often exceed speeds of 120 km/h, with air resistance substantially affecting the overall race times. To date, studies on air resistance in alpine skiing have used wind tunnels and actual skiers to examine the relationship between the gliding posture and magnitude of drag, as well as for the design of skiing equipment. However, these studies have not revealed the flow velocity distribution and vortex structure around the skier. In the present study, we used computational fluid dynamics with the lattice Boltzmann method to derive the relationship between flow velocity in the full tuck position (the downhill racer's speed) and total drag. Furthermore, we visualized the flow around the downhill racer and examined its vortex structure. The results show that the total drag force in the downhill racer model is 27.0 N at a flow velocity of 15 m/s, increasing to 185.8 N at 40 m/s. Moreover, the visualization of the flow field indicates that the primary drag locations at a flow velocity of 40 m/s are the head, upper arms, lower legs, and thighs (including the buttocks). [ABSTRACT FROM AUTHOR]

Background Ski and SnoN proteins function as transcriptional co-repressors in the TGF-β pathway. They regulate cell proliferation and differentiation, and their aberrant expression results in altered TGF-β signalling, malignant transformation, and alterations in cell proliferation. Methods We carried out a comparative characterization of the endogenous Ski and SnoN protein regulation by TGF-β, cell adhesion disruption and actin-cytoskeleton rearrangements between normal and transformed hepatocytes; we also analyzed Ski and SnoN protein stability, subcellular localization, and how their protein levels impact the TGF-β/Smad-driven gene transcription. Results Ski and SnoN protein levels are lower in normal hepatocytes than in hepatoma cells. They exhibit a very short half-life and a nuclear/cytoplasmic distribution in normal hepatocytes opposed to a high stability and restricted nuclear localization in hepatoma cells. Interestingly, while normal cells exhibit a transient TGF-β-induced gene expression, the hepatoma cells are characterized by a strong and sustained TGF-β-induced gene expression. A novel finding is that Ski and SnoN stability is differentially regulated by cell adhesion and cytoskeleton rearrangements in the normal hepatocytes. The inhibition of protein turnover down-regulated both Ski and SnoN co-repressors impacting the kinetic of expression of TGF-β-target genes. Conclusion Normal regulatory mechanisms controlling Ski and SnoN stability, subcellular localization and expression are altered in hepatocarcinoma cells. General significance This work provides evidence that Ski and SnoN protein regulation is far more complex in normal than in transformed cells, since many of the normal regulatory mechanisms are lost in transformed cells. [ABSTRACT FROM AUTHOR]

This paper proposes a new measurement system which measures the reaction force from snow surface for skiing. It is important to analyze the reaction force from snow surface of the skier gliding on the actual snow field to clarify the mechanism of ski turns. In the previous studies, we have used the measurement system of reaction force from snow surface installing the 6-axis force sensor. The system installed the 6-axis force sensor to each foot, and the skier had to carry a data recording PC. Therefore, the entire system was heavy. Furthermore, the system could be used only for the specific ski boots. In this study, we developed a new measurement system of reaction force from snow surface for skiing installing the compact 3-axis force sensors. The 6-axis force components could be calculated by using the information of the compact 3-axis force sensors. We developed a special data logger for saving the sensor outputs, and the skier could glide without loading PC. The system is smaller and lighter than the previous system. The system can be attached between private ski boots and bindings. The system can be adjusted the size of private ski boots. The body of the system was produced by using the personal 3D printer. The verification experiment was conducted to confirm the accuracy of the system. The results of the 6-axis force components calculated by the system were compared to the values of the 6-axis force sensor. These results approximately correspond in all axes. We conducted the measurement experiment of the skier gliding on the actual snow field, and we showed the reaction force from snow surface of the skier by using the system. The system can be applied to motion analysis of the skier gliding on the actual snow field. [ABSTRACT FROM AUTHOR]

An elastic compensation arm hinged at the binding plate and preloaded via a screw was applied to the ski shovel: its effect was to redistribute the pressure applied by the skier on the shovel and to allow the full contact of the edges on the snow during a turn. This enhanced the edge pressure profile at the shovel tip as revealed during bench tests in the lab, thus improving the handling during the turn phase as perceived in the field by expert testers. Results of the study showed that it is possible to modify the edge pressure profile of a ski by means of the application of elastic compensation arms of suitable stiffness, preload and length. The improvement in the field performance is correlated with the specific engineering parameters that can be evaluated in a laboratory setup. [ABSTRACT FROM AUTHOR]

Abstract: Keloids and hypertrophic scars are prevalent disabling conditions with still suboptimal treatments. Basic science and molecular-based medicine research have contributed to unravel new bench-to-bedside scar therapies and to dissect the complex signalling pathways involved. Peptides such as the transforming growth factor beta (TGF-β) superfamily, with Smads, Ski, SnoN, Fussels, endoglin, DS-Sily, Cav-1p, AZX100, thymosin-β4 and other related molecules may emerge as targets to prevent and treat keloids and hypertrophic scars. The aim of this review is to describe the basic complexity of these new molecular scar management strategies and point out new fibrosis research lines. [Copyright &y& Elsevier]

The speed of an alpine ski depends on many properties, including the chemical composition of the base material, the surface structuring of the base and the complex tribology involving the base, the snow and the intermediate water layer that develops as a consequence of solar heating and friction. Using the superhydrophobic properties of some natural leaves as a template, samples of UHMWPE were hot embossed using stainless steel meshes of different mesh sizes using a hot press at constant 300N applied force for different periods of time. It was found that as the mesh size increased, decreasing the surface feature size from 78 to 51μm, the contact angle increased, indicating lower surface wetting and a higher degree of hydrophobicity. In the case of the 325 mesh sample, the contact angle was increased from 78.35° in the virgin untreated sample to 112.84° in the thermally patterned sample. [ABSTRACT FROM AUTHOR]

Abstract: The temperature of snow under skating skis was studied with infrared sensors at four positions and three different velocities. To have an indication of causes and consequences of the heating the friction coefficient with a linear tribometer and the pressure distribution were measured as well. The friction increased with velocity. The highest temperature increase was measured 440mm from the ski end at the highest velocity of 10 m/s. Temperature increase at position 1550mm was independent of velocity. Friction coefficient, pressure distribution and temperature measurements showed a high reliability and allowed to create a model to explain the temperature profile along the ski. [Copyright &y& Elsevier]

Abstract: Measuring ski deflection while skiing allows the characterization of essential aspects of the complex interplay between the skier's performance and the interaction of the ski with the snow. This provides an opportunity to optimize skis with regard to skiers’ skills and athletic ability, thus improving skiing performance. To establish an analysis system, we developed, characterized and tested a system capable of measuring ski deflection while skiing. Using competition-type slalom skis, we applied 30 strain gauge sensors - 15 on each ski. The strain gauges sampled data at 65Hz and the readings were translated into deflection estimates. This was done by validating the system using a specialized bending machine equipped with a laser sensor system to accurately track the changes in ski shape with increasing applied force. We sampled strain gauge data while the bending apparatus deformed the ski. The RMS error of our ski-shape estimates relative to laser-measured data was 11mm. In on slope tests, the center of mass (CoM) position and speed of a skier were acquired using a highly accurate differential Global Navigation Satellite System (dGNSS) at 50Hz and a pendulum model. From this data we estimated the CoM turn radii of carved turns. During the ski tests, the bending radii along the ski over time were obtained from strain gauge data and analyzed for each carved turn. We observed smaller radii relative to the path radii at the tip of a ski. We further analyzed the correlation between ski turn radius from deflection measurements and the CoM turn radius. The RMS error between radii calculated from deflection measurements and CoM radii obtained with a high resolution dGNSS was on average 1.26m, with the smallest error being 0.78m. We tested our system on a hard-snow slope and a soft-snow slope. Our system has manageable technological complexity and is potentially suitable as a training tool or for use in ski-fitting for skiers of various skill levels. [Copyright &y& Elsevier]

Highlights: [•] We examined the preferences for transformations of a mountain landscape. [•] We valued externalities associated with ski and health spa resorts. [•] Past choices of living conditions and actual choices are related. [•] We found similarities between mountain and urban inhabitants attitudes. [ABSTRACT FROM AUTHOR]

Zusammenfassung: Das Verletzungsrisiko beim Ski- und Snowboardfahren sinkt generell in den letzten Jahren. Allerdings ist jedoch ein leichter Anstieg von seltenen schweren Verletzungen wie Schädel-Hirn-Traumata, Rückenmarkverletzungen und Polytraumatisierung zu beobachten. Ursachen sind höhere Geschwindigkeit und extreme und akrobatische Formen der Sportausübung sowie eine gesteigerte Risikoakzeptanz. Die Aufklärung über das Risiko und die Folgen einer möglichen Wirbelsäulenverletzung sind entscheidend, denn die auf dem Markt befindlichen Rückenprotektoren bieten nur einen eingeschränkten Schutz der Wirbelsäule in bestimmten Situationen. [Copyright &y& Elsevier]

Zusammenfassung: Skifahren ist eine traditionsreiche, weltweit beliebte Sportart bei Jung und Alt. Die technische Entwicklung des Skisportes hat vor allem in den letzten 15 Jahren zu einer drastischen Reduktion der Unfälle geführt. Allerdings sind vor allem schwere Bandverletzungen um das Kniegelenk in den Vordergrund gerückt. Hier spielt die Ruptur des vorderen Kreuzbandes die dominante Rolle. Die Einführung der Carving Ski dürfte diese Entwicklung relevant beeinflusst haben. Diese Erkenntnis betrifft den Rennsport wie auch den Hobbyskilauf, wobei die Wahrscheinlichkeit sich bei einem Sturz das vordere Kreuzband zu reißen, bei Frauen signifikant höher ist. Ziel dieses Manuskriptes ist es einen aktuellen Überblick über die medizinische Fachliteratur zu geben. [Copyright &y& Elsevier]

Abstract: This paper proposes the dynamic motion analysis method of ski turns using inertial and force sensors. The motion analysis of ski turns in gliding on an actual field is important to resolve the mechanism of ski turns. However, it is difficult to measure physical exertion due to the severe experimental surrounding such as the outside snow conditions and the weather on the mountain. Therefore, few studies have analyzed ski turns quantitatively. The control force of skier gliding on the actual snow field must be clarified to resolve the mechanism of ski turns. In the previous studies, we developed the 3D posture estimation method of skier gliding at high speed. This method can estimate the Roll- Pitch-Yaw angles in local coordinate by the information of inertial sensors using the Unscented Kalman filter. The control force of skier (joint torque) can be calculated by combining this method and the measurement of reaction force from snow surface. We conducted the experiment of skier gliding on the actual snow field. The inertial sensors were attached to the body segments (upper body, lumber, femur, and lower thigh) of skier and ski boots, and the 6- axis force sensors were installed between boots and skis. The inertial sensors measure angular velocity and acceleration of body segments, and the force sensors measure the reaction force from snow surface. The joint torque (lumber spine, hip, knee and ankle) of skier is calculated by applying the measurement information to the Newton- Euler method. The analysis results using joint torque indicates the control force of skier gliding on the actual snow field. Therefore, the analysis method and results can be used to evaluate the skill of turns and to resolve the mechanism of ski turns. [Copyright &y& Elsevier]

Abstract: This paper deals with the motion analysis of skier gliding on the actual snow field using inertial sensors. It is difficult to measure the motion of skier gliding on the actual snow field since the gliding velocity is fast and the measurement area is large. Therefore, few studies have analyzed ski turns in gliding on the actual snow field. It is necessary to analyze the skier gliding on the actual snow field in resolving the mechanism of ski turns. In our previous study, we developed the motion measurement method of skier using inertial and magnetic field sensors. The 3D posture is estimated by applying the sensor fusion method, and the method can estimate the 3D posture compensating the drift error of gyro sensor and reducing the effect of dynamic acceleration of accelerometer. Furthermore, we developed the sensor fusion method estimating the 3D posture in local coordinate by the information of inertial sensors attaching the body segments. The joint angle of skier in gliding on the actual snow field can be estimated by this method and inverse kinematics. We conducted the measurement experiment by skier gliding on the actual snow field. The inertial sensors and the GPS receiver were attached to the body segments and the top of skier, respectively. Skier conducted carving and skidding turns in this experiment. We calculated the joint angles of skier by the information of inertial sensors, and the switchovers of turns are estimated by the GPS receiver output. The results of motion analysis indicated the major feature of skier's motion and the difference between carving and skidding turns. Therefore, the analysis results can be used to the skill rating, the clarification of the mechanism of ski turns and the suggestion of more ideal turning form. [Copyright &y& Elsevier]

Abstract: The work reports the results of several tests performed on a set of commercial skis ranging from racing to recreational skis by means of a special bench designed for evaluating the Edge Load Profile produced by a ski when pressed against a bed of calibrated load cells. The test bench is equipped with 21 uniaxial load cells of 100mm width and with a linear actuator able to press any type of alpine ski at edging angles ranging from 0¡ to +/- 70¡. The Edge Load Profiles were presented along a normalized ski length and their shapes were compared within each category of skis. The bench output was clearly revealing the presence of critical spots along the ski where either the contact to the ground was missing or some non-uniform peaks were present. The experiences here presented confirm the appropriateness of the Edge Load Profile bench as tool for the skis qualification process and its continuous design improvement. [Copyright &y& Elsevier]

Abstract: Estrogen receptor-α (ERα) and transforming growth factor-beta (TGF-β) signaling pathways are essential regulators during mammary gland development and tumorigenesis. Ski-related novel gene (SnoN) is an oncoprotein and a negative feedback inhibitor of TGF-β signaling. We have previously reported that low expression of SnoN in ERα positive breast carcinomas is associated with favorable prognosis (Zhang et al. Cancer Res. (2003) 63, 5005–5010). Here we have studied the mechanism of a possible cross-talk between ERα and SnoN. We find that SnoN interacts with the estrogen-activated form of ERα in the nucleus. SnoN contains two highly conserved nuclear receptor binding LxxLL-like motifs and we show that mutations in these motifs reduce the interaction of SnoN with ERα. Over-expression of SnoN enhanced the transcriptional activity of ERα in estrogen response element (ERE)-reporter assays, augmented the expression of several ERα target genes and increased the proliferation of MCF7 breast carcinoma cells in an estrogen-dependent manner. Chromatin immunoprecipitation demonstrated that SnoN interacts with ERα at the TTF1 (pS2) gene promoter. Conversely, silencing of SnoN reduced both ERE-reporter activity and the expression of ERα target genes in MCF7 and T-47D breast cancer cells. Histone deacetylase inhibition increased the level of SnoN and SnoN-dependent enhancement of ERα-dependent transcription and SnoN supported the recruitment of p300 histone acetylase to ERα. This study reveals a novel mechanism that interconnects ERα and TGF-β signaling pathways by SnoN. Accordingly, the results indicate that high SnoN level promotes ERα signaling and possibly breast cancer progression. [Copyright &y& Elsevier]

Abstract: This paper proposes the motion analysis method on skiing turn by the measurement system of orientation and gliding trajectory. The orientation measurement system that consists of inertial and magnetic field sensor measures angular velocity, acceleration and magnetic field, on the other hand the gliding trajectory measurement system that consists of the GPS receiver measures latitude, longitude and altitude. The 3D orientation of skier''s body segments and the 3D gliding trajectory on skiing turn are estimated using sensor fusion and the information measured by the orientation measurement systems and the gliding trajectory measurement system attached to skier. The 3D gliding velocity on skiing turn is estimated with the 3D gliding trajectory. The measurement experiment has been conducted by the skier attached the measurement systems on an actual snow field. The joint angle has indicated the gliding form in skidding and carving turn, the gliding trajectory has visualized clearly the difference in moving distance between skidding turn and carving turn. Furthermore, the gliding velocity relative to skier''s coordinate has perceived the different period and the effect of side skidding on these two turns. The experimental results have indicated quantitatively the ever-changing state of skier. The major features of skiing turn can be analyzed by the proposed method, which can use as an effective method for suggesting more ideal turning form, the skill rating, the prevention of disorder and injury from skiing. [Copyright &y& Elsevier]

Abstract: The ability of the cross-country skis to glide freely is of very high importance for both sports and recreational skiing. Significant body of research and development is nowadays devoted to the materials and treatment methods for improving gliding of the ski running surfaces, as well as to the related skiing techniques for optimal use of ski gliding. One of the common concepts here is that the most significant energy loss contribution in such interaction is caused by the pure interfacial friction of the ski running surface and the snow. But this interaction is quite complex and we have proposed that other channels of the energy loss can be of significance. Among the possibilities one can point out to the effects of the snow deformation under the skis, “dragging” of snow by the skis and damping of the ski vibrations by the snow. Present paper reports on the field experimental studies of the ski interaction with the snow. These studies are aiming at developing the measurement technology allowing the assessment of gliding properties of the cross-country skis when data are collected from the sensors placed into the ski track. [Copyright &y& Elsevier]

Abstract: In mammals, the ZAS family of transcription factors activates or represses transcription depending on the cellular context. In the current study, we explored the interaction between ZAS3 and TGFβ1 signaling in epithelial cells using HEK293 cells and the intestinal epithelial cell line, RIE-1. Endogenous ZAS3 expression was detected in each cell line and the small intestine of mice. Additionally, endogenous ZAS3 expression was increased in both whole cell and nuclear lysates by TGFβ1 and in vivo in TGFβ-overexpressing mice, indicating a potential interaction between ZAS3 and TGFβ. ZAS3 transfection enhanced TGFβ1 activation of a luciferase reporter in both HEK293 and RIE-1 cells. Analysis of truncated ZAS3 constructs revealed a 155 amino acid, N-terminal sequence between amino acids 106 and 261 that was required for enhancement of TGFβ1-mediated transcription. Co-immunoprecipitation experiments with nuclear extracts from TGFβ1-stimulated HEK293 cells revealed an association between ZAS3 and the Smad complex. Additionally, transfected ZAS3 decreased the association between the Smad complex and the TGFβ transcriptional repressors Ski and SnoN, indicating a possible mechanism for the enhancement of transcription by exogenous ZAS3. These observations were confirmed by site-directed mutagenesis of ZAS domains homologous with Smad-interacting domains in Ski and SnoN. Finally, ZAS3 transfection enhanced the TGFβ1-mediated induction of α-smooth muscle actin in HEK293 cells, indicating that ZAS3 plays a functional role in TGFβ signaling. In conclusion, we have identified an interaction between ZAS3 and Smad proteins that enhances TGFβ signaling. Since TGFβ signaling is primarily known as a negatively regulated pathway, the enhancement of signaling by ZAS3 has novel implications for understanding TGFβ biology. [ABSTRACT FROM AUTHOR]

Abstract: The Purpose of this work was to present the damping of a ski with piezoelements and to animate a ski with help of energy respectively. The idea was to eliminate the disturbing and allow non–disturbing frequencies. This should be implemented with an active damping system that consists of pizoelements. The result of this project shows that with the help of piezoelements it is possible to react to vibrations engendered by the ski-slope. But if this damping system with its very high mode of action is to be used in the normal ski collection, it has to be made smaller and more efficient. [Copyright &y& Elsevier]

Abstract: Based on the actual measurement on the ski deflection, ski-snow contacting pressure, boot-ski load, turn radius, snow groove geometry in a carved turn and the bending stiffness distribution of the ski, mutual relations have been investigated to elucidate the ski-snow interaction mechanism. Boot-ski load and the contacting pressure distribution on the running surface satisfy force equilibrium and moment equilibrium. The deflection of the ski is related with the moment distribution and bending stiffness distribution of the ski. The pattern of the pressure distribution changed with the bending stiffness distribution of the ski on the same hardness of the snow in the measurement. [Copyright &y& Elsevier]

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Spinal cord injury (SCI) is a leading cause of disability and death worldwide. Reactive astrogliosis, a typical feature of SCI, undergoes various molecular and morphological changes and contributes to glial scar formation, which impedes axonal regeneration. Ski is a novel molecule that regulates the biological characteristics of astrocytes after spinal cord injury, but its function and the exact mechanism of its overexpression in reactive astrocyte proliferation and migration after SCI remain unclear. The purpose of this study was to elucidate the effect and mechanism of Ski on the proliferation and migration of reactive astrocytes, and to regulate the spatiotemporal formation of glial scars after SCI. In an in vitro lipopolysaccharide (LPS)-induced astrocyte injury model, the expression of Ski was upregulated in a time-dependent manner in LPS-induced astrocytes, and the upregulation of Ski was accompanied by that of PCNA, CDK4, CyclinD1, and other proliferation-related proteins. Our findings suggest that Ski promotes the proliferation and migration of reactive astrocytes. Next, astrocytes were transfected with a specific lentivirus to cause the overexpression of Ski, which significantly enhanced the proliferation and migration of reactive astrocytes and LPS-induced activation of the PI3K/Akt pathway. The PI3K/Akt pathway inhibitor LY294002 significantly inhibited the proliferation and migration of LPS-induced reactive astrocytes after Ski overexpression. In conclusion, Ski regulates LPS-induced astrocyte proliferation and migration through the PI3K/Akt pathway, making Ski a promising target for strategies to combat glial scarring after SCI. • LPS can induce astrocyte activation and promote cell proliferation and migration. • The expression of ski increased in LPS induced astrocytes in a time-dependent manner. • Ski overexpression can activate the PI3K/Akt pathway to promote proliferation and migration of reactive astrocytes. • Ski is closely associated with central nervous system injury and repair. • Ski is an important target for glial scar treatment and neurological function recovery after central nervous system injury. [ABSTRACT FROM AUTHOR]

Abstract: The differentiation of myoblasts is regulated by multiple extracellular and intracellular factors. Of the extracellular regulators, members of transforming growth factor-β (TGF-β) family play critical roles in the regulation of osteoblasts and myoblast differentiation. Little is known, however, about the regulation of Myostatin/TGF-β signaling during myoblast differentiation. In this study, we examined the roles of Arkadia, an E3 ubiquitin ligase, in Myostatin/TGF-β signaling and the regulation of myoblast differentiation. Knockdown of Arkadia reduced Myostatin/TGF-β signaling and enhanced the differentiation of C2C12 myoblasts. In addition, exogenous overexpression of Arkadia enhanced Myostatin/TGF-β signaling, preventing myoblast differentiation. In the absence of the activation of Myostatin/TGF-β signaling, knockdown of Arkadia enhanced myoblast differentiation via upregulation of Ski protein, an intracellular enhancer of myoblast differentiation. Arkadia likely affected the differentiation of myoblasts in a Smad-independent fashion by inducing Ski degradation. Knockdown of Arkadia increased the Myostatin-induced phosphorylation of Smad2/3 in C2C12 cells. Arkadia bound Smad2/3 via Ski to induce the ubiquitination of Smad2/3. These results suggest that Arkadia targets Ski-bound, inactive phospho-Smad2/3 to regulate positively Myostatin/TGF-β signaling. Taken together, this study indicates that Arkadia regulates myoblast differentiation through both Smad-dependent and Smad-independent pathways. [Copyright &y& Elsevier]

Abstract: Skiing and snowboarding are leading to a risk of injuries in children. Beginners and experienced have higher risk of injuries, however, the first have less severe injuries than the latest. Risk factors of injury are: ability and experience, binding adjustment, slope characteristics, speed, collisions with objects or jumping and risky behavior of the young skiers and snowboarders. Lower limb injuries are most common in skier, especially knee sprains, conversely snowboarders present more upper limb injuries, especially wrist fractures. The frequency of head injuries does not decrease while helmet use increases but severity decreases. Despite prevention and wearing protections, the frequency of trauma does not decrease significantly, which could be in relation with higher speed and increased risky behavior. Main prevention factors are safety knowledge and safety behavior, correct binding adjustment, and use of protections. [Copyright &y& Elsevier]

Summary: Barrett''s esophagus (BE) is a precancerous condition. However, the mechanisms underlying the transformation from metaplastic to dysplastic to adenocarcinomatous epithelium are still poorly understood. As loss of transforming growth factor-β growth inhibition is considered a hallmark of several human neoplasms, we evaluated the expression of Ski and SnoN (proteins that antagonize transforming growth factor-β signaling through physical interaction with Smad complex and by recruiting histone deacetylases), as markers of the transforming growth factor-β signaling pathway, in BE with and without dysplasia. Biopsy samples from 37 patients (26 men, aged 60 ± 8 years) with histologically proven BE were evaluated; 10 patients had concomitant low-grade dysplasia, 7 high-grade dysplasia (HGD), and 6 HGD associated with adenocarcinoma. Ski and SnoN expression was assessed immunohistochemically. Neither Ski nor SnoN was expressed in normal esophageal epithelium, but both were strongly expressed in BE tissue, with intense cytoplasmic positivity. Expression of these proteins decreased markedly in dysplastic areas in patients with low-grade dysplasia and was absent in those with HGD or HGD/adenocarcinoma. Ski and SnoN proteins are overexpressed in BE and may be involved in abnormal signaling elicited by transforming growth factor-β in this epithelium, enhancing the tumorigenesis process. These observations might help to elucidate the molecular mechanisms involved in the BE tumorigenesis process. [Copyright &y& Elsevier]

Abstract: Signalling by TGF-β ligands through the Smad family of transcription factors is critical for developmental patterning and growth. Disruption of this pathway has been observed in various cancers. In vertebrates, members of the Ski/Sno protein family can act as negative regulators of TGF-β signalling, interfering with the Smad machinery to inhibit the transcriptional output of this pathway. In some contexts ski/sno genes function as tumour suppressors, but they were originally identified as oncogenes, whose expression is up-regulated in many tumours. These growth regulatory effects and the normal physiological functions of Ski/Sno proteins have been proposed to result from changes in TGF-β signalling. However, this model is controversial and may be over-simplified, because recent findings indicate that Ski/Sno proteins can affect other signalling pathways. To address this issue in an in vivo context, we have analyzed the function of the Drosophila Ski/Sno orthologue, SnoN. We found that SnoN inhibits growth when overexpressed, indicating a tumour suppressor role in flies. It can act in multiple tissues to selectively and cell autonomously antagonise signalling by TGF-β ligands from both the BMP and Activin sub-families. By contrast, analysis of a snoN mutant indicates that the gene does not play a global role in TGF-β-mediated functions, but specifically inhibits TGF-β-induced wing vein formation. We propose that SnoN normally functions redundantly with other TGF-β pathway antagonists to finely adjust signalling levels, but that it can behave as an extremely potent inhibitor of TGF-β signalling when highly expressed, highlighting the significance of its deregulation in cancer cells. [Copyright &y& Elsevier]

Abstract: Members of the Ski/Sno family of gene products contain a characteristic peptide domain involved in protein–protein or protein–DNA interaction. Here, we characterize the developmental expression of xDawg, in Xenopus laevis, of a new gene, related to the Ski/Sno family of transcription regulators. The Ski/Sno domain of xDawg is predicted to present an electropositive surface, consistent with a role in DNA binding. This gene is expressed in the marginal zone of early gastrulae, and in the brain, sensory vesicles, and cranial neural crest of neurula and tailbud embryos. [Copyright &y& Elsevier]

Abstract: The aim of this study was to examine the effect of helmet use on non-head–neck injury severity and crash circumstances in skiers and snowboarders. We used a matched case-control study over the November 2001 to April 2002 winter season. 3295 of 4667 injured skiers and snowboarders reporting to the ski patrol at 19 areas in Quebec with non-head, non-neck injuries agreed to participate. Cases included those evacuated by ambulance, admitted to hospital, with restriction of normal daily activities (NDAs) >6 days, with non-helmet equipment damage, fast self-reported speed, participating on a more difficult run than usual, and jumping-related injury. Controls were injured participants without severe injuries or high-energy crash circumstances and were matched to cases on ski area, activity, day, age, and sex. Conditional logistic regression was used to relate each outcome to helmet use. There was no evidence that helmet use increased the risk of severe injury or high-energy crash circumstances. The results suggest that helmet use in skiing and snowboarding is not associated with riskier activities that lead to non-head–neck injuries. [Copyright &y& Elsevier]

Skiing is an important direct input route of per- and polyfluoroalkyl substances (PFASs) to the environment. However, there has been no study on the occurrence of PFASs in Chinese ski area. In this study, 27 neutral PFASs (n-PFASs) and ionic PFASs (i-PFASs), including 4 emerging PFASs, were analyzed in the multimedia samples collected from areas around six ski resorts in Zhangjiakou and Shenyang to investigate the occurrence and seasonal distribution of PFASs. Both i-PFASs and n-PFASs were found in the air (13.2 ± 9.5 pg/m3 and 167 ± 173 pg/m3, respectively) and pine needles [1.44 ± 0.96 ng/g dry weight (dw) and 0.983 ± 0.590 ng/g dw], whereas only i-PFASs were found in the soil (0.755 ± 0.281 ng/g dw) and snow (3.30 ± 2.66 ng/kg). i-PFASs were significantly higher in samples collected around ski resorts than those from rural sites (n = 105, p < 0.05). Significantly higher perfluorooctanoate concentrations were found in the air around the ski resorts in winter (n = 33, p < 0.05). The i-PFASs were stable in the needle, and the short-chain PFASs in the needle could be ascribed to both air and root uptake. More attention should be paid to PFASs emissions in Zhangjiakou with the approaching 2022 Winter Olympic Games. ga1 • PFASs occurred widely in the environmental matrices around Chinese ski resorts. • PFOA and 8:2 FTOH were the predominant i-PFAS and n-PFAS, respectively. • Significantly higher PFAS levels were found around ski resorts than in rural sites. • Ski activities lead to significantly higher levels of PFOA in the air in winter. • Short-chain PFASs in pine needles could be ascribed to both air and root uptake. [ABSTRACT FROM AUTHOR]

Cardiac fibroblast activation to hyper-synthetic myofibroblasts following a pathological stimulus or in response to a substrate with increased stiffness may be a key tipping point for the evolution of cardiac fibrosis. Cardiac fibrosis per se is associated with progressive loss of heart pump function and is a primary contributor to heart failure. While TGF-β is a common cytokine stimulus associated with fibroblast activation, a druggable target to quell this driver of fibrosis has remained an elusive therapeutic goal due to its ubiquitous use by different cell types and also in the signaling complexity associated with SMADs and other effector pathways. More recently, mechanical stimulus of fibroblastic cells has been revealed as a major point of activation; this includes cardiac fibroblasts. Further, the complexity of TGF-β signaling has been offset by the discovery of members of the SKI family of proteins and their inherent anti-fibrotic properties. In this respect, SKI is a protein that may bind a number of TGF-β associated proteins including SMADs, as well as signaling proteins from other pathways, including Hippo. As SKI is also known to directly deactivate cardiac myofibroblasts to fibroblasts, this mode of action is a putative candidate for further study into the amelioration of cardiac fibrosis. Herein we provide a synthesis of this topic and highlight novel candidate pathways to explore in the treatment of cardiac fibrosis. • Cardiac fibroblast mechanosensing uses actin linkage to the extracellular matrix in response to TGF-β • TGF-β stimulates fibrosis in cardiac tissues and there is no effective drug therapy – however, SKI is an endogenous antifibrotic TGF-β repressor. • While SKI inhibits SMAD signaling, it is pleiotropic in nature and may link cytokine and mechanosensory responses to pathological stimuli. • SKI functions as a scaffold to faciliate deactivation of cardiac myofibroblasts, reduced actin polymerization, and its incorporation into stress fibers. • Augmentation and delivery of SKI to the activated fibroblast is a focus for therapeutic treatment of cardiac fibrosis and heart failure [ABSTRACT FROM AUTHOR]

Cellular translation surveillance rescues ribosomes that stall on problematic mRNAs. During translation surveillance, endonucleolytic cleavage of the problematic mRNA is a critical step in rescuing stalled ribosomes. Here we identify NONU-1 as a factor required for translation surveillance pathways including no-go and nonstop mRNA decay. We show that (1) NONU-1 reduces nonstop and no-go mRNA levels; (2) NONU-1 contains an Smr RNase domain required for mRNA decay; (3) the domain architecture and catalytic residues of NONU-1 are conserved throughout metazoans and eukaryotes, respectively; and (4) NONU-1 is required for the formation of mRNA cleavage fragments in the vicinity of stalled ribosomes. We extend our results in C. elegans to homologous factors in S. cerevisiae , showing the evolutionarily conserved function of NONU-1. Our work establishes the identity of a factor critical to translation surveillance and will inform mechanistic studies at the intersection of translation and mRNA decay. • NONU-1 represses nonstop and no-go mRNA decay targets • The Smr RNase domain of NONU-1 is required for mRNA repression • NONU-1-dependent mRNA cleavages occur in the vicinity of stalled ribosomes • NONU-1 function and catalytic residues are conserved throughout eukaryotes Glover et al. report that NONU-1 is an endoribonuclease required for some mRNA cleavages after ribosome stalling during nonstop and no-go decay. In addition, NONU-1-independent mechanisms contribute to target mRNA degradation. Identification of NONU-1 should create a more complete picture of the molecular events underpinning relief from ribosome stalls. [ABSTRACT FROM AUTHOR]

Upper limb injuries are a common occurrence in snowboarders, and these may be reduced by wearing wrist guards that transmit the force of the fall across the forearm. We present a case of a 26-year-old man who experienced a displaced left radial and ulnar fracture related to wearing a wristwatch while snowboarding. The wristwatch acted as a fulcrum around which the arm was fractured, serving as a stress riser that focused the force of the fall. The fracture was treated using open reduction and internal fixation. [ABSTRACT FROM AUTHOR]