Low Intensity Levels Research Articles

Studying the X-ray absorption characteristics of Centaurus X-3 using nearly 14 years of MAXI/GSC data

Centaurus X-3 is a persistent high-mass X-ray binary with the long-term light curve from the source exhibiting orbit-to-orbit intensity variations with no apparent superorbital periodicity. We used sim 13.5 years of MAXI /GSC data to study the long-term behaviour of X-ray absorption caused by the stellar wind from the companion star and any absorbing structures present in the binary. We used orbital-phase-resolved spectroscopy to study the variation in the photoelectric absorption along the line of sight of the source for both the intensity-averaged data and intensity-resolved data after dividing all the data binned with orbital period into three intensity levels. We find an asymmetric variation in the photoelectric absorption along the line of sight across an orbit of the source. The orbital-phase-resolved spectra show a clear increase in photoelectric absorption after $ orb 0.5, which deviates from a spherically symmetric stellar wind model. The flux of Cen X-3 shows significant variation between consecutive orbits. An intensity-resolved spectral analysis of the source was performed, followed by an intensity-resolved and orbital-phase-resolved spectral analysis, which showed that at the medium and high intensity levels, the orbital-phase-resolved photoelectric absorption is slightly asymmetric with respect to mid-phase ($ orb =$ 0.5). The asymmetry is very pronounced at the lowest intensity level and cannot be explained by a spherically symmetric wind from the companion star. The differences in the orbital phase-dependence of absorption for different intensity levels suggest that the presence of an accretion wake, photoionization wake, or tidal stream is more prominent at a lower intensity level for Centaurus X-3 than at a higher intensity level.

Unsteady relationships between instantaneous surface heat flux, instantaneous surface temperature, and tracked shock wave phenomena

Investigated are unsteady relationships between surface heat flux variations, surface temperature fluctuations, and tracked shock wave phenomena. The level of coherence and time lag between events at different flow locations are used to quantify the associated interactions at different frequencies. With this approach, time-varying surface heat flux and surface temperature fluctuations are used to track events at different flow locations relative to unsteadiness associated with the test section inlet and relative to unsteadiness associated with different shock wave phenomena. Employed for the investigation is a specialty test section with an inlet Mach number of 1.54, which contains a normal shock wave, a lambda foot (which is comprised of an upstream oblique shock wave leg, and a downstream oblique shock wave leg), and a flow separation zone beneath the lambda foot. High and low unsteady Mach wave intensity levels are produced at the test section inlet by different numbers and different amounts of unsteadiness of families of intersecting and interacting Mach waves, as these are located within and just downstream of the test section entrance. When correlated with respect to normal shock wave tracked locations, values and magnitudes of the most highly correlated frequency bands are different depending upon the level of test section inlet unsteady Mach wave intensity, and the location where unsteady flow events originate. With low freestream unsteady Mach wave intensity at the test section inlet, unsteady events are generally present at normal shockwave locations prior to times when their influences are present at thin film temperature and heat flux gage surface locations. The presence of high unsteady Mach wave intensity at the test section inlet produces an environment wherein the low Mach wave intensity inlet flow is overwhelmed by highly active Mach wave fluctuations, when they are present, such that the normal shock wave is no longer a primary originating source of flow unsteadiness.

Seismic Resilience Assessment for Steel-concrete Composite Bridges including Impacts of Near-fault Earthquakes

This paper proposes a seismic resilience assessment method for steel-concrete composite bridges (SCCB) considering near-fault earthquake hazards. Based on conventional probabilistic seismic hazard disaggregation analysis, a correction factor is defined to represent the proportion of the occurrence probability of the near-fault pulse-like, near-fault non-pulse-like and far-field earthquake conditioned on a given intensity level concerning the total occurrence probability of all earthquakes. The parameters of functionality recovery functions are modified using the factor proposed, and then the restoration processes after each type of earthquake are estimated. Correspondingly, vulnerabilities of a typical SCCB under near-fault and far-field earthquakes are developed as a case study. Based on the seismic hazard and fragility results, the seismic risk for each type of earthquake in a 50-year horizon is estimated. After that, the modified functionality recovery function is derived from the expected functionality. For implementation of the method proposed, the expected seismic resilience indices of a typical SCCB involved in the SEQBRI project are estimated, and the seismic resilience assessment is conducted. For comparison analysis, the seismic resilience assessment without considering earthquake type is also conducted using the same bridge. The result shows that the seismic resilience of bridges in near-fault earthquake scenarios can be analyzed by the method proposed, and reducing the structural vulnerability under low-intensity level earthquakes and improving the structural recovery efficiency for slight and moderate damage states are more meaningful to enhance the seismic resilience of bridges.

In situ nitrogen-doped graphene-TiO2 nano-hybrid as an efficient photocatalyst for pollutant degradation.

To solve environmental-related issues (wastewater remediation, energy conservation and air purification) caused by rapid urbanization and industrialization, synthesis of novel and modified nanostructured photocatalyst has received increasing attention in recent years. We herein report the facile synthesis of in situ nitrogen-doped chemically anchored TiO2 with graphene through sol-gel method. The structural analysis using X-ray diffraction showed that the crystalline nitrogen-doped graphene-titanium dioxide (N-GT) nanocomposite is mainly composed of anatase with minor brookite phase. Raman spectroscopy revealed the graphene characteristic band presence at low intensity level in addition to the main bands of anatase TiO2. X-ray photoelectron spectroscopy analysis disclosed the chemical bonding of TiO2 with graphene via Ti-O-C linkage, also the substitution of nitrogen dopant in both TiO2 lattice and into the skeleton of graphene nanoflakes. UV-Vis absorption spectroscopy analysis established that the modified material can efficiently absorb the longer wavelength range photons due to its narrowed band gap. The N0.06-GT material showed the highest degradation efficiency over methylene blue (MB, ∼98%) under UV and sulfamethoxazole (SMX, ∼ 90.0%) under visible light irradiation. The increased activity of the composite is credited to the synergistic effect of high surface area via greater adsorption capacity, narrowed band gap via increased photon absorption, and reduced e-/h+ recombination via good electron acceptability of graphene nanoflakes and defect sites (Ti3+ and oxygen vacancy(Vo)). The ROS experiments further depict that primarily hydroxyl radicals (OH•) and superoxide anions (O2•-) are responsible for the pollutant degradation in the process redox reactions. In summary, our findings specify new insight into the fabrication of this new material whose efficiency can be further tested in applications like H2 production, CO2 conversion to value-added products, and in energy conservation and storage.

Nanoscale optical nonreciprocity with nonlinear metasurfaces

Optical nonreciprocity is manifested as a difference in the transmission of light for the opposite directions of excitation. Nonreciprocal optics is traditionally realized with relatively bulky components such as optical isolators based on the Faraday rotation, hindering the miniaturization and integration of optical systems. Here we demonstrate free-space nonreciprocal transmission through a metasurface comprised of a two-dimensional array of nanoresonators made of silicon hybridized with vanadium dioxide (VO2). This effect arises from the magneto-electric coupling between Mie modes supported by the resonator. Nonreciprocal response of the nanoresonators occurs without the need for external bias; instead, reciprocity is broken by the incident light triggering the VO2 phase transition for only one direction of incidence. Nonreciprocal transmission is broadband covering over 100 nm in the telecommunication range in the vicinity of λ = 1.5 µm. Each nanoresonator unit cell occupies only ~0.1 λ3 in volume, with the metasurface thickness measuring about half-a-micron. Our self-biased nanoresonators exhibit nonreciprocity down to very low levels of intensity on the order of 150 W/cm2 or a µW per nanoresonator. We estimate picosecond-scale transmission fall times and sub-microsecond scale transmission rise. Our demonstration brings low-power, broadband and bias-free optical nonreciprocity to the nanoscale.

Seismic Fragility and Reliability of Base-Isolated Structures with Regard to Superstructure Ductility and Isolator Displacement Considering Degrading Behavior

ABSTRACT The present study investigates the effects of the degradation of mechanical properties (pinching, stiffness degradation, and strength degradation) in load-deformation relationship of the superstructures equipped with friction pendulum systems on the seismic fragility and reliability results. An equivalent two-degree-of-freedom model is employed, in which the Bouc-Wen hysteretic model characterizes the inelastic behavior of both the superstructure and the isolator. To examine a wide variety of system combinations with different structural properties and degradation severity, a comprehensive parametric study is performed. Incremental dynamic analyses are carried out to develop fragility functions. Subsequently, the seismic reliability of both the superstructure and the isolation level is assessed. Results indicate that the negative effects of degrading behavior are more prominent in stiff superstructures as it significantly decreases structural capacity and reliability indices. It is demonstrated that the system is primarily influenced by pinching behavior rather than degradation in strength and stiffness, especially at low intensity levels that correspond to lower limit-states. In the majority of investigated systems, the seismic demand in the isolator decreases when superstructures undergo degrading behavior. Overall, such effects should be considered in the reliability-based design procedure to attain design consistency in terms of reliability. The results of this paper that account for the degrading effects enable reliable estimations of key parameters essential for the design of the superstructure and the isolator.

An examination of urban green spaces usage behaviours and self-perceived mental health benefits: findings from two urban green neighbourhoods in Pakistan

ABSTRACT The present study examined urban green space users’ self-perceived mental health benefits of visiting green spaces in Pakistan – one of South Asia’s rapidly urbanizing countries. By using a quantitative-based cross-sectional survey, 384 participants were surveyed in green urban neighbourhood settings. It was found that most green space users believed that their visits to green spaces have at least some positive effects on the different parameters of their mental health, such as stress or anxiety levels, mood, energy levels, optimism levels, confidence levels, or concentration levels, among others. The study explored that the frequency and duration of green space usage and intensity of activity performed in the green space have an important role in determining the degree of the self-perceived mental health benefits of visiting green spaces, suggesting the importance of green interventions, including physical changes in the environment and social promotion activities to encourage green space usage among urban dwellers. Moreover, the study revealed low green space usage and activity intensity levels among certain sub-population groups compared to others, such as women, young adults, or the elderly, highlighting the need to ensure equity of access to green spaces for all sub-population groups and prioritize them in intervention strategies.

Impact of donor-specific antibody with low mean fluorescence intensity on allograft outcomes in kidney transplant

BackgroundImmune-mediated rejection is the most common cause of allograft failure in kidney transplant (KT) patients. Exposure to alloantigen, including human leukocyte antigen (HLA), results in the production of donor-specific antibodies (DSA). There are limited data about low levels of mean fluorescence intensity (MFI) DSA, especially post-transplantation. This study evaluated allograft outcomes in KT patients with low MFI DSA. MethodsFrom January 2007 to December 2021, KT patients who were tested for post-transplant DSA at Ramathibodi Hospital, Bangkok, Thailand, with the DSA MFI ≤ 1000 were evaluated. These KT patients were categorized into two groups: very low DSA (VLL; MFI = 1–500) and low DSA (LL; MFI = 501–1000). All KT patients were evaluated for the primary outcomes, such as the incidence of acute rejection, serum creatinine levels at one and five years after transplantation as well as allograft and patient survivals. ResultsAmong 36 KT patients 25 were included as those with VLL and 11 as those with LL. The LL group had significantly higher T-cell mediated allograft rejection (TCMR) than the VLL group (45% vs. 12%, P = 0.04). In addition, 10 patients, 5 in the VLL group and 5 in the LL group developed antibody-mediated allograft rejection (ABMR). Both TCMR and ABMR were confirmed by biopsy results. There was a trend toward higher MFI in KT patients with ABMR than without ABMR (P = 0.22). At 5 post-transplant years, serum creatinine, allograft and patient survivals were comparable between these two groups. Furthermore, the univariate and multivariate analyzes revealed that the LL group was a high risk for rejection. ConclusionLow MFI DSA values after transplantation may be associated with a higher incidence of rejection, but this finding did not show differences in allograft and patient survival in this study's analysis.

Impact of Exercise Intensity on Cardiovascular Disease in a Rat Model of Hypertension: A Systematic Review and Meta-Analysis

Objective: Hypertension increases the risk of morbidity and mortality including stroke, myocardial infarction, and other serious complications. To prevent these events, regular exercise has been recommended as a nonpharmacological intervention for hypertensive patients, but the optimal exercise intensity, in response to the variation of the condition, remains a subject of investigation. Therefore, our study investigates the impact of exercise training on the disease progression in spontaneously hypertensive rats (SHR), a well-established rat model of hypertension. Specifically, we aim to perform a meta-analysis that measures the effects of low, moderate, and high-intensity exercise on at least one of the following cardiovascular variables: systolic blood pressure (SBP), mean arterial pressure (MAP), and resting heart rate (RHR). Hypothesis: We hypothesize that the meta-analysis findings will determine that treadmill training at low and moderate intensities will significantly improve SBP, MAP, and RHR in SHRs. We also anticipate that we will find that high intensity will produce less benefit due to its stress-inducing effects. Methods: We performed a meta-analysis adhering to the PRISMA guidelines. A systematic search for scientific studies was conducted in the CINAHL, EMBASE, SPORTDiscus, and SciFinder databases using the following key words: “spontaneously hypertensive rat,” and “exercise” yielded 900+ research articles. Subsequent selection of articles included studies that comprised of only treadmill running, more than 45 minutes of exercise per day during the training period, at least five days of training per week, and a duration of at least four weeks. Finally, eligible studies included at least one of the three cardiovascular parameters. Each study was categorized into low, moderate, or high intensity based on either treadmill speed or VO2 max, or both. Quantitative SBP, MAP, and RHR data were extracted from the included studies. Results: A total of 90 studies are included in this qualitative analysis, 9.6% of which include female rats. Preliminary data analysis evaluating means for each intensity determined that all levels of intensity significantly benefited the measured cardiovascular parameters. However, the degree of benefit was greater in the low and moderate intensities as compared to the high intensity. Conclusion: All levels of intensity exercise had a beneficial response to lowering cardiovascular parameters in SHR, however, low and moderate levels of intensity produced the greatest effects. The failure of high-intensity exercise to improve cardiovascular outcomes may suggest a role played by oxidative stress and merits further investigation. Further subgroup analysis based on sex, age, and duration of exercise will be conducted to determine if these confounding variables play role in modulating these benefits. This research was supported by the MJ Murdock charitable trust. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Variation of volatile compounds and sensory profile for Protaetia brevitarsis larvae fermented with lactic acid bacteria and yeast

This study aimed to investigate the correlation between the composition of volatile compounds, consumer acceptance, and drivers of (dis)liking of Protaetia brevitarsis larvae fermented using lactic acid bacteria and yeast. Volatile compounds were analyzed using HS-SPME-Arrow-GC–MS, and a sensory evaluation was conducted with 72 consumers. A total of 113 volatile compounds were detected, and principal component analysis indicated that the samples could be divided into three groups. The calculated relative odor activity values (ROAV) revealed the presence of 27 compounds (ROAV >1). Volatile compounds with high ROAV were predominantly found during yeast fermentation. The sensory evaluation results indicated a strong correlation between low levels of off-odor intensity and high odor liking, emphasizing that odor profile had a more direct association with consumer acceptance than odor intensity. These findings suggest that yeast fermentation using volatile compounds, which positively influences consumer acceptance, is appropriate for Protaetia brevitarsis larvae.

Smart city and earnings management: Evidence from China.

Smart cities improve services for businesses, among many other benefits. A comprehensive understanding and effective utilization of these advantages is crucial for promoting business development. Using panel data from Chinese listed companies (2010-2020), this study employs a multi-stage DiD model to investigate the impact of smart cities on corporate earnings management. The findings indicate that the smart city pilot policy has significantly reduced corporate earnings management. Further analysis suggests that smart cities primarily reduce earnings management by improving firms' external information environments. Additionally, the results show that the policy impact of smart cities is more significant in regions with lower regulatory intensity or higher marketization levels, compared to regions with higher regulatory intensity or lower marketization levels. Similarly, firms in less concentrated markets or those more closely related to smart city development tend to experience greater reductions in earnings management due to smart city construction, unlike firms in more concentrated markets or those less involved. Finally, this paper offers several brief suggestions.

Submaximal, Low-Dose Eccentric vs Traditional Cycling Exercise: Reduced Oxygen Uptake and Pulmonary Artery Pressure Assessed by Echocardiography in Healthy Middle-aged Adults. A Randomized Controlled, Crossover Trial

ObjectiveTo investigate the ventilatory and circulatory differences between eccentric (ECC) and concentric (CON) cycling exercise at submaximal, low-dose intensity from onset to end-exercise in healthy middle-aged participants. DesignRandomized controlled crossover trial. SettingThe participants underwent 1 ECC and 1 CON test according to stepwise incremental exercise protocols at identical, submaximal intensities. Breath-by-breath analyses of ventilatory gas exchange and echocardiography were used to assess cardiopulmonary function during exercise. Participants24 healthy middle-aged, untrained participants (14 women, 10 men, 50±14 years) were included. Interventions1 ECC and 1 CON test at submaximal intensities. Main Outcome MeasureThe main outcome was oxygen uptake (V'O2). ResultsThe V'O2 increase was reduced by -422 mL/min (-52%, 95% confidence interval: -513 to -292, P<.001) during ECC, as well as the ventilatory drive. Echocardiographic parameters, heart rate (-14%), cardiac output (-21%), stroke volume (-15%), and pulmonary artery pressure by tricuspid regurgitation pressure gradient (TRPG) (-26%) were also significantly reduced during ECC compared with CON at identical intensities. Participants reported significantly less dyspnea and unchanged perceived leg fatigue in ECC. ConclusionECC was well tolerated, and significant reductions were observed in V'O2, ventilation, and right ventricular load compared with CON, even at low intensity levels. This study, conducted on healthy middle-aged participants, did not raise concerns that would hinder further investigation of the effects of ECC in patients with severely limited cardiopulmonary disease, and it calls for further research on this topic.

Experimental and numerical investigation of the hysteretic behavior of reinforced concrete column-steel beam interior joints under low seismic intensity levels

For the composite frame structure of concrete column and steel beam, a connection structure based on ribbed angle steel connector (RASC) is proposed, and the hysteresis performance and force transmission mechanism of this new type of composite joint are studied. Through quasi-static experimental research, the influence of beam and column cross-sectional dimensions on the bearing capacity, energy dissipation capacity, stiffness degradation, ductility, and failure form of the frame structure was analyzed. The results of experimental and finite element analysis show that the failure forms of this joint under low-cycle repeated loading are mainly manifested as the shear failure of concrete in the core area of beams and columns and sliding failure between angle steel connectors and steel beams, and the hysteresis curves of the joints are similar to those of frame beams and columns, respectively.

Reciprocal association between pain and quality of life after newly acquired spinal cord injury.

Pain is highly prevalent in spinal cord injury (SCI) and a key determinant of quality of life (QoL). This is the first study to examine reciprocal associations between pain and QoL in patients undergoing their first inpatient rehabilitation after SCI. Longitudinal data, with three measurement time points (1month and 3months after SCI onset, and at discharge from inpatient rehabilitation) from the Inception Cohort of the Swiss Spinal Cord Injury Cohort Study. Participants were 381 individuals aged ≥ 16years with a newly diagnosed traumatic or non-traumatic SCI. 75.1% were male and the average age was 53.2years. Random intercept cross-lagged panel models were conducted to examine the reciprocal association between pain intensity and QoL, as measured with the International SCI QoL Basic Data Set three individual items (satisfaction with life, physical health, and psychological health) and total score (mean of the three individual items). Both item and total QoL scores increased over time. 1month: 5.3 (SD = 2.7), 3months: 5.9 (SD = 2.3), discharge: 6.6 (SD = 2.0). Participants reported relatively low levels of pain intensity that remained stable over the course of inpatient rehabilitation. 1month: 2.7 (SD = 2.3), 3months: 2.6 (SD = 2.4), discharge: 2.7 (SD = 2.5). There were no significant cross-lagged associations between QoL and pain intensity across time. Results indicate that pain intensity does not predict changes in QoL during first rehabilitation, and vice versa. Associations between pain intensity and QoL reported by previous studies may be attributable to individual characteristics and timely events that simultaneously influence pain and QoL.

The eyes as the exclamation mark of the face: exploring the relationship between eye size, intensity of female facial expressions and attractiveness in a range of emotions.

The eyes play an important role in communicating emotions and shape the determination of other facial attributes. Here, we explored the relationship between eye size, perceived intensity and attractiveness of facial expressions. A sample of N = 63 participants (men and women, aged 18-35) rated attractiveness and emotional intensity for images displaying emotionally expressive women's faces with digitally manipulated eye size (15% smaller, unchanged, or 15% larger). The analysis of perceived intensity showed an interaction parameter between eye size and gender. Female individuals reported differences when comparing unchanged and larger eyes; male participants showed differences across all eye size comparisons (smaller-unchanged, smaller-larger, unchanged-larger). Regarding perceived attractiveness, faces with smaller eyes registered lower mean scores than both unchanged and larger. The lowest intensity level was associated with neutral faces and the highest with fearful ones. Faces displaying happiness were perceived as the most attractive. Larger eyes seem to make emotions more intense and attractive. We suggest that the more intense phenomenon serves an evolutive purpose, as it might encourage caretaking behavior.

Employee education, labor protection intensity and auditor risk perception.

Prior literature finds senior executives can influence auditor decision making. However, few studies have discussed the impact of employee's personal characteristics. Our research aims to fill the above research gaps by examining the impact of employee level education on audit costs. Taking A-share listed companies in Shanghai and Shenzhen from 2006 to 2021 as the research object, this paper examines the impact of employee education on audit fees. It is found that highly educated employees can effectively reduce the audit fees borne by the company, but the implementation of the Labor Protection Law weakens this inhibitory effect. In the case of low marketization level and weak Confucian culture intensity, employee education level has a more significant inhibitory effect on audit fees of listed companies. This study provides a basis for empirical research on the impact of employee attributes on auditor decision making, provides a new research perspective on the impact of labor protection law at the corporate micro level, and enriches the theoretical research on corporate governance rooted in traditional Chinese culture. We contribute to the practice that implications for evaluating the effectiveness of adopting labor protection.

Wire Electrical Discharge Machining of AISI304 and AISI316 Alloys: A Comparative Assessment of Machining Responses, Empirical Modeling and Multi-Objective Optimization

This research investigates the multi-response of both material removal rate (MRR) and surface roughness (Ra) for the wire electrical discharge machining (WEDM) of two stainless steel alloys: AISI 304 and AISI 316. Experimental results are utilized to compare the machining responses obtained for AISI 316 with those obtained for AISI 304, as previously reported in the literature. The experimental work is conducted through a full factorial experimental design of five running parameters with different levels: applied voltage, transverse feed, pulse-on/pulse-off times and current intensity. The machined workpieces are analyzed using an image processing technique in order to evaluate the size of cut slots to allow the calculation of the MRR. Followed by the characterization of the surface roughness along the side walls of the slots. Different mathematical regression techniques were developed to represent the multi-response of both materials using the MATLAB regression toolbox. It was found that WEDM process parameters have a fuzzy influence on the responses of both material models. This allowed for multi-objective optimization of the regression models using four different techniques: multi-objective genetic algorithm (MOGA), multi-objective pareto search algorithm (MOPSA), weighted value grey wolf optimizer (WVGWO) and osprey optimization algorithm (OOA). The optimization results reveal that the optimal WEDM parameters of each response are inconsistent to the others. Hence, the optimal results are considered a compromise between the best results of different responses. Noteworthily, the multi-objective pareto search algorithm outperformed the other candidates. Eventually, the optimal results of both materials share the high voltage, high transverse feed rate and low pulse-off time parameters; however, AISI 304 requires low pulse-on time and current intensity levels while AISI 316 optimal results entail higher pulse-on time and current levels.

Translation to German and linguistic validation of the Rapid Assessment of Physical Activity (RAPA) questionnaire

PurposeTo produce a culturally adapted translation of the Rapid Assessment of Physical Activity (RAPA) questionnaire for German speaking Austrians and to conduct a linguistic validation of the new language version.MethodsThe original English RAPA questionnaire was translated into German for Austria and underwent an independent forward and back translation, followed by cognitive debriefing interviews with older adults aged 55 to 78 years with and without health conditions (n = 13), for linguistic validation.ResultsSeveral distinct choices were made in the translation of the RAPA questionnaire to German, including the use of colloquial terms for ‘physical activity’ and ‘intensity’; and the decision to keep to the original examples and images of different physical activities for illustrating the intensity levels (light, moderate, vigorous) of physical activity. In cognitive debriefing, interviewees commented that some example activities for the respective intensity levels could – depending on the individual – also represent a higher or lower intensity level; and that the wording of RAPA items 4 and 5, which describe the category ‘under-active regular’ aerobic activity, was difficult to understand. Both issues were addressed and resolved through minor iterative modifications made during the cognitive debriefing process.ConclusionsA new version of the RAPA questionnaire in German for Austria has been produced by forward and back translation and linguistic validation. The questionnaire may now undergo psychometric evaluation.

Effects of single and repeated shock wave application on the osteogenic differentiation potential of human primary mesenchymal stromal cells and the osteoblastic cell line MG63 in vitro.

Introduction: Extracorporeal shock wave therapy is a non-invasive and effective option for treating various musculoskeletal disorders. Recent literature indicates that the parameters for extracorporeal shock wave therapy, such as the optimal intensity, treatment frequency, and localization, are yet to be determined. Studies reporting on the effects of shock wave application on primary mesenchymal stromal cells (MSCs) as well as osteoblastic cell lines in vitro are barely available and not standardized. Methods: In this study, we designed a special setup to precisely expose primary MSCs and the osteoblastic cell line MG63 to shock waves and subsequently analyzed the resulting cellular responses using standardized protocols to investigate their viability, proliferation behavior, cytokine secretion, and osteogenic differentiation potential in vitro. The shock wave transducer was coupled to a specifically designed water bath containing a 5mL tube holder. Primary human MSCs and MG63 cells were trypsinated and centrifuged in a 5mL tube and exposed to single and repeated shock wave application using different intensities and numbers of pulses. Results: Single treatment of MSCs using intensities 5, 10, 15, and 20 and pulse numbers 100, 250, 500, 750, and 1,000 at a constant pulse repetition frequency of 1Hz resulted in a decreased viability and proliferation of both cell types with an increase in the intensity and number of pulses compared to controls. No significant difference in the osteogenic differentiation was observed at different time intervals in both cell types when a single shock wave application was performed. However, repeated shock wave sessions over three consecutive days of primary MSCs using low intensity levels 0.1 and 1 showed significant osteogenic differentiation 4-fold higher than that of the extracted Alizarin Red S at day 14, whereas MG63 cells showed no significant osteogenic differentiation compared to their corresponding controls. More specifically, repeated shock wave application triggered a significant downregulation of COL1A1, upregulation of RUNX2, and sustained increase of OCN in primary MSCs but not in the cell line MG63 when induced toward the osteogenic differentiation. Discussion: The effects of shock wave application on MSCs make it an effective therapy in regenerative medicine. We established a protocol to analyze a standardized shock wave application on MSCs and were able to determine conditions that enhance the osteogenic differentiation of MSCs in vitro.

Search for Signs of Sublimation-Driven Dust Activity of Primitive-Type Asteroids Near Perihelion

—In December 2021 to February 2022, the UBVRI photometry of 29 primitive-type asteroids of the Main Belt, being near the perihelion distances, was carried out at the 0.6-meter RC600 semiautomatic telescope of the Caucasus Mountain Observatory (CMO) of the Sternberg Astronomical Institute, Moscow State University. These observations, as well as the data processing and analysis, were aimed at searching for supposed sublimation-driven dust activity on asteroids under maximal subsolar temperatures. Among the tasks to be accomplished was the comparison of the physical and dynamic parameters of active and inactive asteroids. The main result is that substantial spectral signs of quasi-simultaneous sublimation-driven dust activity were detected on six primitive-type asteroids of the Main Belt—145 Adeona, 302 Clarissa, 322 Phaeo, 435 Ella, 690 Wratislavia, and 779 Nina (on 302 Clarissa, 322 Phaeo, 435 Ella, and 690 Wratislavia—for the first time). These six asteroids represent ~21% of all bodies included in the observation program. Probable spectral manifestations of activity at a lower intensity level were detected for the first time on five more asteroids—424 Gratia, 751 Faina, 762 Pulcova, 778 Theobalda, and 859 Bouzaréah. On 145 Adeona and 779 Nina, sublimation-driven dust activity near perihelion was registered for the third time for the last ten years; this time interval corresponds to about three orbital periods of these asteroids around the Sun. We consider the circumstances due to which five of the listed asteroids possess families. General processes and conditions that could and/or can influence the portion of primitive-type asteroids that quasi-simultaneously show signs of sublimation-driven dust activity are discussed.