Is surface roughness of direct resin composite restorations material and polisher-dependent? A systematic review.

STATEMENT OF PROBLEM: Direct resin composite bonding offers a highly esthetic, minimally invasive option for the treatment of anterior teeth however the challenge to improve their longevity remains. Direct resin composite restorations are limited by the risk of staining which may be influenced by the final surface roughness (Ra) of composite achieved. PURPOSE: The purpose of this review is to investigate, using a systematic approach, whether the final surface roughness of anterior composite restorations is affected by the interaction between resin composite and polishing systems. MATERIALS AND METHODS: The review was conducted by 3 independent reviewers and included articles published up to January 21, 2021. Three electronic databases were searched: Medline, Embase, and Web of Science. Studies assessing a quantitative effect of polishing methods on the Ra of direct composite resin materials published after the year 2000 and restricted to the English language were included. RESULTS: The database search for the effect of polishing systems on composite materials retrieved 125 eligible studies. Twelve duplicate records were removed. The resulting records were screened using title and abstract leading to 38 reports which were sought for retrieval. Application of eligibility criteria led to 11 studies included in the review. Hand searching of these studies yielded no additional papers. CONCLUSIONS: There is insufficient evidence to determine whether combination of composite and polisher influences final Ra. More research is required to determine if there is an optimum combination of polisher and composite. CLINICAL IMPLICATIONS: Polishing should be completed following planned finishing procedures. The approximation to the final surface and which finishing burs to use, if any, should be considered when planning a restoration. Durafill VS predictably achieves an acceptable Ra by different polishers.

Threshold concepts in medical education: A scoping review.

INTRODUCTION: The threshold concept framework (TCF) was first described nearly 20 years ago, but its application in the field of medical education has recently seen a significant growth of interest with a diverse range of literature published on the subject. The transformative nature of threshold concepts (TCs) offers potential for the design of learning experiences and curricula across the medical education continuum. A scoping review was conducted to map the extent of the current literature regarding TCs in medical education-to describe the types of available evidence and its focus-and identify research gaps. METHODS: The review followed the JBI Manual for Evidence Synthesis approach for scoping reviews. Four databases and two additional websites were searched for articles exploring TCs in medical education. Data were analysed using quantitative and qualitative thematic approaches. A framework of conceptual change was used to synthesise the TCs identified. RESULTS: Thirty-six papers, spanning undergraduate, postgraduate and continuing medical education, were included in the final analysis. The most frequent application of the TCF was in the identification of TCs, which related to basic scientific knowledge, ways of thinking and ways of practising in medicine. Uncertainty, patient care, clinical reasoning and professional identify formation were themes that emerged at multiple stages of training. Several papers evaluated the use of the TCF in teaching. CONCLUSION: The understanding and embodiment of TCs increases in complexity across the medical education continuum, with TCs recurring with changes in clinical environment and responsibilities. This lends support to a holistic approach to curriculum design spanning all stages of training. Further research is needed to develop a consistent approach for describing and applying the TCF in medical education and to address how the TCF can be used in teaching and how threshold crossing can be measured.

Ventilatory responses to whole body cryotherapy.

The effects of whole body cryotherapy (WBC) on measures of respiratory function, and their interaction with sex and anthropometry, are unknown. This study investigated ventilatory responses after WBC and examined the role of sex and anthropometric characteristics in 22 recreationally active male and female participants. Thermal sensation [TS], heart rate, blood pressure and ventilatory measures (expired volume [V˙E], oxygen consumption [V˙O2], respiratory exchange ratio and metabolic equivalents of task [METS]) were evaluated pre- and post-WBC, compared to a control condition. V˙E increased by 10.8 L.min-1 following WBC compared to 0.1 L.min-1 in the control session (p=.001). V˙O2 increased by 0.4 L.min-1 following WBC compared to 0.0 L.min-1 in the control session (p<.001). METS increased by 1.0 following WBC compared to 0.1 in the control session (p<.001). TS decreased by 2 following WBC compared to 0 in the control session (p<.001), with females' TS decreasing significantly more than males following WBC (p=.001). Following a WBC exposure, highly significant strong negative relationships were observed between fat mass index and ΔV˙O2 (p=.002, r=-.718), body fat percentage and ΔV˙O2 (p=.003, r=-.700), fat mass index and ΔMETS (p=.001, r=-.729), body fat percentage and ΔMETS (p=.004, r=-.676). Furthermore, strong, statistically significant positive correlations were observed following a WBC exposure between BSA to mass ratio and TS (p=.005, r=-.669), TS and BSA (p<0.001, r=.776) and fat free mass index and TS (p=.001, r=.745). A short exposure to WBC elicits a ventilatory response via increased V˙O2, V˙E and METS. The largest increases occur within the first minute post-exposure, but return to near resting levels 1 min post-WBC. Increases in V˙O2, V˙E and METS observed post-WBC are likely due to an acute transient shivering response due to cold air exposure.

Individualising the exposure of -110°C whole body cryotherapy: The effects of sex and body composition.

The purpose of this study was to investigate the effects of whole body cryotherapy (WBC) on a range of thermoregulatory measures. We also sought to examine the influence of sex and body composition. A convenience sample of 18 healthy participants (10 males and 8 females) (27±6yr) volunteered for this study. Temperature (core, tympanic, skin and mean body), heart rate, blood pressure, and thermal comfort and sensation were recorded pre- and post- (immediately and every 5min until 35min post) exposure to a single bout of WBC (30s at -60°C, 150s at 110°C). Anthropometric data (height, weight, body surface area, body mass index, fat mass and fat free mass) were also recorded. No significant differences in temperature (core, tympanic, skin and mean body), heart rate, blood pressure, or thermal comfort / sensation were observed between male and females at baseline. Immediately post WBC mean body (male:31.9±0.8°C; female:31.0±0.9°C; ∆ mean body temperature:0.9±0.1°C; P≤0.05, d=0.64) and mean skin (male:22.1±2.2°C; female:19.6±2.8°C; ∆ mean skin temperature:-2.5±0.6°C; d=0.99, P≤0.05) temperature was significantly different between sexes. Sex differences were also observed in regional skin temperature (male thigh, 20.8±1.1°C; female thigh, 16.7±1.1°C, ∆ mean thigh skin temperature:-4.1°C; d=3.72; male calf, 20.5±1.1°C; female calf, 18.2±1°C, ∆ mean calf skin temperature:-2.3±0.1°C; d=3.61; male arm, 21.7±1°C; female arm, 19±0.4°C, ∆ mean arm skin temperature: -2.7±0.3°C; d=3.54; P≤0.05). Mean arterial pressure was significantly different over time (P≤0.001) and between sexes (male 0mins:94±10mmHg; female 0mins:85±7mmHg; male 35mins:88±7mmHg; female 35mins:80±6mmHg; P≤0.05). Combined data set indicated a strong negative relationship between skin temperature and body fat percentage 35min' post WBC (r=-0.749, P≤0.001) and for core temperature and body mass index in males only (r=0.726, P≤0.05) immediately after WBC. There were no significant differences between sexes in any other variables (heart rate, tympanic and perceptual variables). We observed sex differences in mean skin and mean body temperature following exposure to whole body cryotherapy. In an attempt to optimise treatment, these differences should be taken into account if whole body cryotherapy is prescribed.

Does the Wim Hof Method have a beneficial impact on physiological and psychological outcomes in healthy and non-healthy participants? A systematic review.

INTRODUCTION: Wim Hof, also known as the iceman, developed a method called Wim Hof Method (WHM) which he claims to have several benefits on physical and mental health. The aim of this systematic review is to identify and synthesise the results of the studies conducted on WHM on physiological and psychological health-related outcomes. MATERIALS AND METHODS: This systematic review followed the PRISMA guidelines for systematic reviews. The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42022333209. Medline and Web of Science were searched and included studies from January 1, 2014, to July 4, 2022. Studies were included if they met the predetermined inclusion/exclusion criteria. Inclusion criteria included RCTs and cohort studies published in peer-reviewed journals, studies conducted on healthy individuals and people with pre-existing medical conditions (adolescents and adults over the age of 14), studies that included all three pillars (breathing, cold exposure, and commitment) of the WHM, and studies that only focused on Wim Hof breathing method (WHBM). Exclusion criteria included studies that discussed WHM but are not original experimental research or are not peer-reviewed, studies that included children under the age of 14, and studies that used methods similar to WHM, but not actually WHM, such as tummo meditation. The articles were assessed for risk of bias using RoB 2.0 and Scottish Intercollegiate Guidelines Network (SIGN) tools. The effects of WHM were categorised into physiological or psychological related outcomes and narrative synthesis was conducted. RESULTS: Nine papers were included in this review which consisted of eight individual trials. The findings suggest that the WHM may reduce inflammation in healthy and non-healthy participants as it increases epinephrine levels, causing an increase in interleukin-10 and a decrease in pro-inflammatory cytokines. Additionally, effect of WHBM on exercise performance showed mixed findings. Effects on respiratory parameters of minute ventilation, tidal volume, and breathing frequency were mixed following bouts of exercise. CONCLUSION: Taken together, the findings of this review show promising use of WHM in the inflammatory response category. The focus of future studies should further investigate the benefits of WHM in non-healthy participants with inflammatory disorders and explore the use of Wim Hof breathing method to enhance exercise performance.

Hoof Impact and Foot-Off Accelerations in Galloping Thoroughbred Racehorses Trialling Eight Shoe-Surface Combinations.

The athletic performance and safety of racehorses is influenced by hoof−surface interactions. This intervention study assessed the effect of eight horseshoe−surface combinations on hoof acceleration patterns at impact and foot-off in 13 galloping Thoroughbred racehorses retired from racing. Aluminium, barefoot, GluShu (aluminium−rubber composite) and steel shoeing conditions were trialled on turf and artificial (Martin Collins Activ-Track) surfaces. Shod conditions were applied across all four hooves. Tri-axial accelerometers (SlamStickX, range ±500 g, sampling rate 5000 Hz) were attached to the dorsal hoof wall (x: medio-lateral, medial = positive; y: along dorsal hoof wall, proximal = positive; and z: perpendicular to hoof wall, dorsal = positive). Linear mixed models assessed whether surface, shoeing condition or stride time influenced maximum (most positive) or minimum (most negative) accelerations in x, y and z directions, using ≥40,691 strides (significance at p < 0.05). Day and horse−rider pair were included as random factors, and stride time was included as a covariate. Collective mean accelerations across x, y and z axes were 22−98 g at impact and 17−89 g at foot-off. The mean stride time was 0.48 ± 0.07 s (mean ±2 SD). Impact accelerations were larger on turf in all directions for forelimbs and hindlimbs (p ≤ 0.015), with the exception of the forelimb z-minimum, and in absolute terms, maximum values were typically double the minimum values. The surface type affected all foot-off accelerations (p ≤ 0.022), with the exception of the hindlimb x-maximum; for example, there was an average increase of 17% in z-maximum across limbs on the artificial track. The shoeing condition influenced all impact and foot-off accelerations in the forelimb and hindlimb datasets (p ≤ 0.024), with the exception of the hindlimb impact y-maximum. Barefoot hooves generally experienced the lowest accelerations. The stride time affected all impact and foot-off accelerations (p < 0.001). Identifying factors influencing hoof vibrations upon landing and hoof motion during propulsion bears implication for injury risk and racing outcomes.

Jockey Perception of Shoe and Surface Effects on Hoof-Ground Interactions and Implications for Safety in the Galloping Thoroughbred Racehorse.

Riding racehorses is a high-risk profession and optimizing safety alongside performance is paramount. Horseshoes play a critical role in providing traction with the ground surface and are therefore a major determinant of safety. However, the subjective perceptions of expert riders influence attitudes towards using different shoes and must be taken into consideration before any changes may be implemented. This study used a questionnaire-based method to evaluate jockey opinion of four shoeing conditions (aluminum, steel, GluShu, and barefoot) trialed at gallop over turf and artificial surfaces. Nine Lickert-style questions explored impact, cushioning, responsiveness, grip, uniformity, smoothness of ride, safety, adaptation period, and overall rating for each shoe-surface combination. A total of 94 questionnaires, based on 15 horse-rider pairs, were assessed using descriptive statistics and linear mixed models performed in SPSS (P < .05). Data indicate that shoe type significantly affected all question responses, with the exception of impact. Surface-type significantly affected perception of grip and safety. Overall, jockeys showed a preference for aluminum and steel shoes across both artificial and turf tracks. These rated "excellent" and were considered to be "very supportive" in approximately 80% of trials, with a 100% "active" response, good grip, and a quick adaptation period. In contrast, barefoot and GluShu conditions were generally considered "moderately supportive," with barefoot appearing favorable on the artificial surface. On turf, barefoot was deemed the least smooth and the only condition that jockeys sometimes marked "unsafe" (17% of responses). Future work aims to investigate the relationship between jockey opinion and hoof kinematic data.

Influence of Speed, Ground Surface and Shoeing Condition on Hoof Breakover Duration in Galloping Thoroughbred Racehorses.

Understanding the effect of horseshoe-surface combinations on hoof kinematics at gallop is relevant for optimising performance and minimising injury in racehorse-jockey dyads. This intervention study assessed hoof breakover duration in Thoroughbred ex-racehorses from the British Racing School galloping on turf and artificial tracks in four shoeing conditions: aluminium, barefoot, aluminium-rubber composite (GluShu) and steel. Shoe-surface combinations were tested in a randomized order and horse-jockey pairings (n = 14) remained constant. High-speed video cameras (Sony DSC-RX100M5) filmed the hoof-ground interactions at 1000 frames per second. The time taken for a hoof marker wand fixed to the lateral hoof wall to rotate through an angle of 90 degrees during 384 breakover events was quantified using Tracker software. Data were collected for leading and non-leading forelimbs and hindlimbs, at gallop speeds ranging from 23-56 km h-1. Linear mixed-models assessed whether speed, surface, shoeing condition and any interaction between these parameters (fixed factors) significantly affected breakover duration. Day and horse-jockey pair were included as random factors and speed was included as a covariate. The significance threshold was set at p < 0.05. For all limbs, breakover times decreased as gallop speed increased (p < 0.0005), although a greater relative reduction in breakover duration for hindlimbs was apparent beyond approximately 45 km h-1. Breakover duration was longer on turf compared to the artificial surface (p ≤ 0.04). In the non-leading hindlimb only, breakover duration was affected by shoeing condition (p = 0.025) and an interaction between shoeing condition and speed (p = 0.023). This work demonstrates that speed, ground surface and shoeing condition are important factors influencing the galloping gait of the Thoroughbred racehorse.

The effect of horseshoes and surfaces on horse and jockey centre of mass displacements at gallop.

Horseshoes influence how horses' hooves interact with different ground surfaces, during the impact, loading and push-off phases of a stride cycle. Consequently, they impact on the biomechanics of horses' proximal limb segments and upper body. By implication, different shoe and surface combinations could drive changes in the magnitude and stability of movement patterns in horse-jockey dyads. This study aimed to quantify centre of mass (COM) displacements in horse-jockey dyads galloping on turf and artificial tracks in four shoeing conditions: 1) aluminium; 2) barefoot; 3) GluShu; and 4) steel. Thirteen retired racehorses and two jockeys at the British Racing School were recruited for this intervention study. Tri-axial acceleration data were collected close to the COM for the horse (girth) and jockey (kidney-belt), using iPhones (Apple Inc.) equipped with an iOS app (SensorLog, sample rate = 50 Hz). Shoe-surface combinations were tested in a randomized order and horse-jockey pairings remained constant. Tri-axial acceleration data from gallop runs were filtered using bandpass Butterworth filters with cut-off frequencies of 15 Hz and 1 Hz, then integrated for displacement using Matlab. Peak displacement was assessed in both directions (positive 'maxima', negative 'minima') along the cranio-caudal (CC, positive = forwards), medio-lateral (ML, positive = right) and dorso-ventral (DV, positive = up) axes for all strides with frequency ≥2 Hz (mean = 2.06 Hz). Linear mixed-models determined whether surfaces, shoes or shoe-surface interactions (fixed factors) significantly affected the displacement patterns observed, with day, run and horse-jockey pairs included as random factors; significance was set at p<0.05. Data indicated that surface-type significantly affected peak COM displacements in all directions for the horse (p<0.0005) and for all directions (p≤0.008) but forwards in the jockey. The largest differences were observed in the DV-axis, with an additional 5.7 mm and 2.5 mm of downwards displacement for the horse and jockey, respectively, on the artificial surface. Shoeing condition significantly affected all displacement parameters except ML-axis minima for the horse (p≤0.007), and all displacement parameters for the jockey (p<0.0005). Absolute differences were again largest vertically, with notable similarities amongst displacements from barefoot and aluminium trials compared to GluShu and steel. Shoe-surface interactions affected all but CC-axis minima for the jockey (p≤0.002), but only the ML-axis minima and maxima and DV-axis maxima for the horse (p≤0.008). The results support the idea that hoof-surface interface interventions can significantly affect horse and jockey upper-body displacements. Greater sink of hooves on impact, combined with increased push-off during the propulsive phase, could explain the higher vertical displacements on the artificial track. Variations in distal limb mass associated with shoe-type may drive compensatory COM displacements to minimize the energetic cost of movement. The artificial surface and steel shoes provoked the least CC-axis movement of the jockey, so may promote greatest stability. However, differences between horse and jockey mean displacements indicated DV-axis and CC-axis offsets with compensatory increases and decreases, suggesting the dyad might operate within displacement limits to maintain stability. Further work is needed to relate COM displacements to hoof kinematics and to determine whether there is an optimum configuration of COM displacement to optimise performance and minimise injury.

A systematic review and meta-analysis of the effects of foam rolling on range of motion, recovery and markers of athletic performance.

OBJECTIVE: To conduct a systematic review with meta-analysis assessing the effects of foam rolling on range of motion, laboratory- and field-based athletic measures, and on recovery. DATA SOURCES: MEDLINE, PubMed, EMBASE, SPORTDiscus and Science Direct were searched (2005-June 2018). STUDY SELECTION: Experimental and observational studies were included if they examined the effects of foam rolling on measures of athletic performance in field or laboratory settings. DATA EXTRACTION: Two investigators independently assessed methodologic quality using the Physiotherapy Evidence Database (PEDro) Scale. Study characteristics including participant age, sex and physical activity status, foam rolling protocol and pre- and post-intervention mean outcome measures were extracted. DATA SYNTHESIS: A total of 32 studies (mean PEDro = 5.56) were included in the qualitative analysis, which was themed by range of motion, laboratory-based measures, field-based measures and recovery. Thirteen range of motion studies providing 18 datasets were included in the meta-analysis. A large effect (d = 0.76, 95% CI 0.55-0.98) was observed, with foam rolling increasing range of motion in all studies in the analysis. CONCLUSIONS: Foam rolling increases range of motion, appears to be useful for recovery from exercise induced muscle damage, and there appear to be no detrimental effect of foam rolling on other athletic performance measures. However, except range of motion, it cannot be concluded that foam rolling is directly beneficial to athletic performance. Foam rolling does not appear to cause harm and seems to elicit equivalent effects in males and females.

Cardiovascular diseases and risk factors knowledge and awareness in people with type 2 diabetes mellitus: a global evaluation.

AIM: Cardiovascular diseases (CVD) are the leading cause of death in people living with type 2 diabetes mellitus (T2D). The aim of this study was to explore the knowledge and awareness of CVD and related risk factors in people living with T2D, globally. METHODS: A questionnaire consisting of 17 questions was used to conduct the Taking Diabetes to Heart survey, between September 2017 and May 2018 among people living with T2D. All categorical variables are presented as numbers and percentages. Pearson's chi-square test and Fisher's exact test were used to assess the association between categorical variables. RESULTS: A total of 12,695 respondents living with T2D in 133 countries completed the questionnaire. Almost half of the respondents (44%) reported having lived with diabetes for more than nine years. Only one in six (17%) considered themselves at high risk of CVD, which was surprising given that almost all the respondents had at least one CVD risk factor and around 28% of respondents had experienced one or more CVD events in the past. Although the majority of the respondents indicated they have had CVD risk factors, one in six (17%) had never discussed their risk with a health professional (HP). Furthermore, one in eleven (9%) did not know about CVD and its associated risk factors. CONCLUSION: To mitigate the prevalence of CVD in people living with diabetes, it is required to work with HP to increase knowledge and awareness of people with T2D about diabetes complications, in particular CVD.

Chronic hypoxia up-regulates expression of adenosine A1 receptors in DDT1-MF2 cells.

As the first step to understand how chronic hypoxia might regulate smooth muscle function in health and disease, we have employed an established immortalised cell model of smooth muscle, DDT1-MF2 cells, to address the hypothesis that adenosine A1 receptor density is modulated by O2 availability. Maximal specific binding (Bmax) of the selective adenosine A1 receptor antagonist, [3H]-DPCPX, to cell membranes increased 3.5-fold from 0.48 +/- 0.02 pmol/mg to 1.7 +/- 0.5 pmol/mg protein after 16 hr of hypoxia and this effect was not accompanied by any statistically significant changes in either binding affinity (0.84 +/- 0.2 nM vs. 1.2 +/- 0.3 nM) or Hill coefficient (1.1 +/- 0.1 vs. 0.99 +/- 0.03). Hypoxia-evoked increases in membrane receptor density were paralleled in intact DDT1-MF2 cells. In addition, the increase in [3H]-DPCPX binding to intact cells was inhibited by co-incubation during hypoxia with the translational inhibitor cycloheximide, the transcriptional blocker actinomycin D and the NFkappaB inhibitor sulphasalazine. Together, these data show that adenosine A1 receptor density is modulated, at least in part, by O2-dependent activation of the transcription factor NFkappaB and adds to the list of processes dynamically regulated by ambient oxygen availability. Since hypoxia is an initiating factor in acute renal failure, similar changes in transcription may account for up-regulation of adenosine A1 receptors noted previously in the renal vasculature of rats with acute renal failure.