Shoulder Anteroinferior Glenoid Labrum Reconstruction With the Long Head of the Biceps Tendon Restores Glenohumeral Stability: A Cadaveric Biomechanical Study.

PURPOSE: The purpose of this cadaveric study was to determine feasibility and assess biomechanical stability of glenoid labral reconstruction utilizing the long head of the biceps tendon (LHBT) as a local autograft for labral deficient shoulders. METHODS: Ten cadaveric shoulders underwent resection of all soft tissue structures except the labrum and LHBT. The scapula and humerus were separately attached to a custom shoulder testing apparatus allowing for 22.5 N of compressive isotonic force across the joint. An Instron (Electroplus 1000) measured the peak force (N) as the humeral head was translated over the anteroinferior glenoid rim through 10 cycles. Shoulders were tested in 3 separate scenarios: intact labrum, resected labrum from 3- to 6-o'clock (for a right shoulder), and labral reconstruction with the LHBT. Reconstruction was performed by performing LHBT tenotomy at the level of the pectoralis major insertion. The proximal LHBT tendon, left attached to the supraglenoid tubercle, was then attached to the anteroinferior glenoid rim with suture anchors. RESULTS: Mean (SD) length of the LHBT was 76.1 (12.9 mm) and the diameter was 5.9 (1.6) mm. Peak force for intact labrum was significantly greater than the deficient labrum state (14.06 vs 11.78 N; P = .012). Peak force for labral reconstruction (16.67 N) was significantly greater than both intact and deficient labral states (P < .001 and P = .011, respectively). In all specimens, the length for the LHBT to the pectoralis major insertion was sufficient for reconstruction of the labrum to the 6-o'clock position. CONCLUSIONS: Glenoid labrum reconstruction with the LHBT is a feasible option to restore glenohumeral stability, with peak force to displacement significantly greater than the labral-intact and labral-deficient states. CLINICAL RELEVANCE: This reconstruction may be an option for augmentation in the labral-deficient shoulder.

Experimental evidence on promotion of electric and improved biomass cookstoves.

Improved cookstoves (ICS) can deliver "triple wins" by improving household health, local environments, and global climate. Yet their potential is in doubt because of low and slow diffusion, likely because of constraints imposed by differences in culture, geography, institutions, and missing markets. We offer insights about this challenge based on a multiyear, multiphase study with nearly 1,000 households in the Indian Himalayas. In phase I, we combined desk reviews, simulations, and focus groups to diagnose barriers to ICS adoption. In phase II, we implemented a set of pilots to simulate a mature market and designed an intervention that upgraded the supply chain (combining marketing and home delivery), provided rebates and financing to lower income and liquidity constraints, and allowed households a choice among ICS. In phase III, we used findings from these pilots to implement a field experiment to rigorously test whether this combination of upgraded supply and demand promotion stimulates adoption. The experiment showed that, compared with zero purchase in control villages, over half of intervention households bought an ICS, although demand was highly price-sensitive. Demand was at least twice as high for electric stoves relative to biomass ICS. Even among households that received a negligible price discount, the upgraded supply chain alone induced a 28 percentage-point increase in ICS ownership. Although the bundled intervention is resource-intensive, the full costs are lower than the social benefits of ICS promotion. Our findings suggest that market analysis, robust supply chains, and price discounts are critical for ICS diffusion.

Patient-reported outcome scores following patellar instability surgery-high prevalence does not equal high responsiveness: a systematic review.

PURPOSE: The purpose of this study was to determine the utilization and responsiveness of common patient-reported outcomes (PROs) in patients undergoing surgery for patellar instability. METHODS: Using PRISMA guidelines, a systematic review of studies reporting outcomes following surgical intervention for patellar instability was conducted using Pubmed, Cochrane, OVID Medline, and Google Scholar. Subgroup analysis of articles reporting at least two PROs with baseline and follow-up data were used to evaluate responsiveness of instruments using relative efficiency and effect size. RESULTS: From the search, 2,848 unique articles were found, of which 178 were included in final analysis (7,122 patients, mean age 22.6, 63.6% female). The most commonly used PRO was the Kujala score (79.2%), followed by the Lysholm (34.8%), and Tegner (30.9%). Seventy-nine articles were eligible for subgroup analysis. The Kujala had a higher relative efficiency than ten of the 14 instruments to which it was compared but had lower relative efficiency compared to the IKDC and Lysholm scores. The Banff Patella Instability Instrument (BPII) and the Norwich score, condition-specific tools, were unable to be fully assessed due to rarity of use and lack of comparisons. CONCLUSION: The hypothesis that the Kujala score is the most commonly used PRO for patellar instability, although other instruments offer greater efficiency was supported by our results. The IKDC and Lysholm scores had similar effect sizes but higher relative efficiencies than the Kujala, thus suggesting better responsiveness. This analysis adds useful information for surgeons on the effectiveness of the most common PRO's for evaluating patellofemoral instability outcomes. LEVEL OF EVIDENCE: Level III.

A community engagement strategy to sustain safe drinking water in Guatemala.

OBJECTIVE: We sought to examine a community engagement (CE) strategy, defined as a monetary contribution, on water filter usage DESIGN: A natural, quasi-experimental study was conducted in Guatemala following the distribution of water filters. Households in the 2014-2015 group (free water filter) were compared with households in the 2018-2019 group (CE strategy: US$5.50 for water filter) SAMPLE: One-year post-distribution, the comparison group (n = 56) and intervention group (n = 38) completed a survey on family health and water filter use RESULTS: Households in the CE group had almost five times higher odds (OR = 4.7, p = .022) of having a working water filter 1 year later. Using a multivariable logistic regression model, the single best predictor to explain working water filters was the CE strategy CONCLUSIONS: CE strategies that support ownership and dignity might sustain public health initiatives, in conjunction with collaborative international partnerships. Future research could include linking villages with local and international organizations that support safe drinking water initiatives.

Tetracycline use in treating osteoarthritis: a systematic review.

BACKGROUND AND AIMS: The purpose of the review was to synthesize the current literature regarding tetracyclines in the treatment of osteoarthritis. METHODS: Using multiple databases, a systematic review was performed with customized search terms crafted to identify studies examining doxycycline or minocycline in the treatment of osteoarthritis. Results were classified into basic science mechanistic studies, in vivo animal studies, and human clinical trials. A total of 1446 potentially relevant studies were reviewed, and after exclusion criteria were applied, 23 investigations were included in the final analysis. RESULTS: From 12 basic science mechanistic studies, we report on three main mechanisms by which tetracyclines may exert benefit in osteoarthritis progression: matrix metalloproteinase inhibition, immunomodulation, and nitric oxide synthase inhibition. Seven animal studies showed generally encouraging results. Four articles reported human clinical studies, showing mixed results in the treatment of osteoarthritis, potentially related to the choice of patient population, primary outcomes, and timing of treatment. CONCLUSION: Tetracyclines have the potential to benefit osteoarthritis patients via multiple mechanisms. Further study is warranted to examine the optimal dose and timing of tetracycline treatment in osteoarthritis.

Pitch break and performance metrics remain unchanged in pitchers who returned to the same level of play after ulnar collateral ligament reconstruction in Major League Baseball pitchers.

BACKGROUND: The ulnar collateral ligament is commonly injured in overhead-throwing athletes, particularly baseball pitchers. Pitch movement (break) is a critical aspect to pitching performance. The primary purpose of this study was to determine the changes in pitch velocity, pitch break, angle of break, and pitch performance metrics before and after ulnar collateral ligament reconstruction (UCLR) in Major League Baseball (MLB) pitchers. The secondary purpose was to determine changes in pitch performance metrics before and after UCLR. We hypothesized that pitch break and pitch performance metrics would be unchanged following UCLR. MATERIALS AND METHODS: This was a retrospective case-series study of pitchers who had undergone primary UCLR between 2008 and 2014. Velocity, horizontal movement (Hmov), and vertical movement (Vmov) of each pitch were collected from the PITCHf/x system for each pitcher 12-24 months before surgery, 12-24 months after surgery, and 24-36 months after surgery. Overall break was calculated by taking the Pythagorean sum of Hmov and Vmov. Angle of break was determined by taking the inverse tangent of Vmov divided by Hmov. Repeated-measures analysis of covariance was performed to determine differences in pitch velocity, movement, angle of movement, and performance metrics between preoperative and postoperative time frames. Performance metrics included balls, strikes, swings, fouls, swings and misses, ground balls, line drives, pop-ups, fly balls, and home runs. Covariates included age at surgery, time from MLB debut to surgery, innings pitched as a starter, innings pitched as a reliever, and total pitches thrown. RESULTS: In a cohort of 46 pitchers who underwent UCLR between 2008 and 2014, pitch velocity, movement, and angle were not significantly changed with respect to preoperative or postoperative time frames. In addition, postoperative time frames had clinically insignificant differences in pitch performance metrics. CONCLUSION: Pitch break and performance metrics are not significantly affected in pitchers who return after UCLR.

Ptychographic amplitude and phase reconstruction of bichromatic vortex beams.

We experimentally demonstrate that ptychographic coherent diffractive imaging can be used to simultaneously characterize the amplitude and phase of bichromatic orbital angular momenta-shaped vortex beams, which consist of a fundamental field, together with its copropagating second-harmonic field. In contrast to most other orbital angular momentum characterization methods, this approach solves for the complex field of a hyperspectral beam. This technique can also be used to characterize other phase-structured illumination beams, and, in the future, will be able to be extended to other complex fields in the extreme ultraviolet or X-ray spectral regions, as well as to matter waves.

The effect of hydrostatic pressure on model membrane domain composition and lateral compressibility.

Phase separation in ternary model membranes is known to occur over a range of temperatures and compositions and can be induced by increasing hydrostatic pressure. We have used small angle X-ray scattering (SAXS) to study phase separation along pre-determined tie lines in dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC) and cholesterol (CHOL) mixtures. We can unequivocally distinguish the liquid ordered (Lo) and liquid disordered (Ld) phases in diffraction patterns from biphasic mixtures and compare their lateral compressibility. The variation of tie line endpoints with increasing hydrostatic pressure was determined, at atmospheric pressure and up to 100 MPa. We find an extension and shift of the tie lines towards the DOPC rich region of the phase diagram at increased pressure, this behaviour differs slightly from that reported for decreasing temperature.

Temperature and pressure tuneable swollen bicontinuous cubic phases approaching nature's length scales.

Bicontinuous cubic structures offer enormous potential in applications ranging from protein crystallisation to drug delivery systems and have been observed in cellular membrane structures. One of the current bottlenecks in understanding and exploiting these structures is that cubic scaffolds produced in vitro are considerably smaller in size than those observed in biological systems, differing by almost an order of magnitude in some cases. We have addressed this technological bottleneck and developed a methodology capable of manufacturing highly swollen bicontinuous cubic membranes with length scales approaching those seen in vivo. Crucially, these cubic systems do not require the presence of proteins. We have generated highly swollen Im3m symmetry bicontinuous cubic phases with lattice parameters of up to 480 Å, composed of ternary mixtures of monoolein, cholesterol and negatively charged lipid (DOPS or DOPG) and we have been able to tune their lattice parameters. The swollen cubic phases are highly sensitive to both temperature and pressure; these structural changes are likely to be controlled by a fine balance between lipid headgroup repulsions and lateral pressure in the hydrocarbon chain region.

Calcium kinetics during bed rest with artificial gravity and exercise countermeasures.

UNLABELLED: We assessed the potential for countermeasures to lessen the loss of bone calcium during bed rest. Subjects ingested less calcium during bed rest, and with artificial gravity, they also absorbed less calcium. With exercise, they excreted less calcium. To retain bone during bed rest, calcium intake needs to be maintained. INTRODUCTION: This study aims to assess the potential for artificial gravity (AG) and exercise (EX) to mitigate loss of bone calcium during space flight. METHODS: We performed two studies: (1) a 21-day bed rest (BR) study with subjects receiving 1 h/day AG (n = 8) or no AG (n = 7) and (2) a 28-day BR study with 1 h/day resistance EX (n = 10) or no EX (n = 3). In both studies, stable isotopes of Ca were administered orally and intravenously, at baseline and after 10 days of BR, and blood, urine, and feces were sampled for up to 14 days post dosing. Tracers were measured using thermal ionization mass spectrometry. Data were analyzed by compartmental modeling. RESULTS: Less Ca was absorbed during BR, resulting in lower Ca balance in BR+AG (-6.04 ± 3.38 mmol/day, P = 0.023). However, Ca balance did not change with BR+EX, even though absorbed Ca decreased and urinary Ca excretion increased, because endogenous excretion decreased, and there was a trend for increased bone deposition (P = 0.06). Urinary N-telopeptide excretion increased in controls during BR, but not in the EX group. Markers of bone formation were not different between treatment groups for either study. Ca intake decreased during BR (by 5.4 mmol/day in the AG study and 2.8 mmol/day in the EX study), resulting in lower absorbed Ca. CONCLUSIONS: During BR (or space flight), Ca intake needs to be maintained or even increased with countermeasures such as exercise, to enable maintenance of bone Ca.

Reduction of edge-localized mode intensity using high-repetition-rate pellet injection in tokamak H-mode plasmas.

High repetition rate injection of deuterium pellets from the low-field side (LFS) of the DIII-D tokamak is shown to trigger high-frequency edge-localized modes (ELMs) at up to 12× the low natural ELM frequency in H-mode deuterium plasmas designed to match the ITER baseline configuration in shape, normalized beta, and input power just above the H-mode threshold. The pellet size, velocity, and injection location were chosen to limit penetration to the outer 10% of the plasma. The resulting perturbations to the plasma density and energy confinement time are thus minimal (<10%). The triggered ELMs occur at much lower normalized pedestal pressure than the natural ELMs, suggesting that the pellet injection excites a localized high-n instability. Triggered ELMs produce up to 12× lower energy and particle fluxes to the divertor, and result in a strong decrease in plasma core impurity density. These results show for the first time that shallow, LFS pellet injection can dramatically accelerate the ELM cycle and reduce ELM energy fluxes on plasma facing components, and is a viable technique for real-time control of ELMs in ITER.

Injury rates in the National Football League during the 2020 COVID-19 season.

OBJECTIVES: The National Football League (NFL) altered the 2020 season due to the COVID-19 pandemic, which resulted in canceled preseason games and a dynamic regular season schedule to accommodate for canceled games. The purpose of this study was to evaluate if the disrupted training and preseason schedule lead to increased injury rates as seen in other professional sports. We hypothesized that the overall injury rate would be higher in the 2020 season compared to the 2018-2019 seasons and that this increase will affect all body regions equally. METHODS: Publicly released NFL weekly injury reports were queried to identify players listed as out or placed on the injured reserve for at least one game in the 2018-2020 seasons. Injuries were categorized into upper extremity, lower extremity, spine/core, head, illness, not injury related and undisclosed injuries. Incidents per 1000 athlete exposures were calculated for the prior two seasons (2018-2019) and for the 2020 season separately. Percentage of injuries occurring in each position was calculated separately for the pre-COVID-19 (2018 and 2019) and post-COVID-19 (2020) cohorts. Incidence rate ratios (IRR) and confidence intervals were used to compare injury rates in 2018-2019 versus 2020. The z-test for proportions was used to determine significant differences between injury incidences. RESULTS: The overall incidence rate per 1000 athlete exposures in 2020 was not significantly different compared to pre-COVID-19 seasons (21.6 versus 23.1, IRR 0.94, 95% CI: 0.9-1.0 p > 0.999). The proportion of injuries by position did not change before and after COVID-19 either (p > 0.999). Out listings due to illness were significantly increased during the 2020 season (0.8 versus 0.3, IRR 2.8, 95% CI: 1.4-5.2, p = 0.004). CONCLUSION: The incidence of NFL injuries did not significantly change in 2020. The distribution of injuries did not change with respect to position.

Satellite cell count, VO(2max) , and p38 MAPK in inactive to moderately active young men.

Satellite cells (SCs) are responsible for muscle repair following strenuous exercise or injury. SC responses to intervention have been studied, but most studies do not discuss or take into account the substantial variability in SC number among young individuals. We hypothesized that an active lifestyle reflected in higher VO(2max) may be associated with greater SC number. As training alters basal p38-mitogen-activated protein kinase (MAPK) activity, which is associated with SC proliferation, SC count may also correlate with this stress signaling kinase. Muscle biopsies from vastus lateralis of eight male participants were analyzed for fiber type, myogenin, and p38/phospho-p38 MAPK using SDS-PAGE and Western blotting. Immunofluorescence was used to detect Pax7(+) SCs. Two weeks following the biopsy, subjects underwent an incremental treadmill test to determine VO(2max) . A strong positive correlation (P = 0.0087) was found between the number of Pax7(+) nuclei and VO(2max) . Pax7(+) cell number correlated negatively with phospho-p38/p38 MAPK (P = 0.0006), but had no correlation with fiber type or myogenin. SC number is proportional to VO(2max) , and hence it can be postulated that higher levels of physical activity activate SC proliferation but not fusion, underlining the relevance of exercise in stimulating SC pool size even without injury.

A red palm oil diet can reduce the effects of oxidative stress on rat spermatozoa.

Male Wistar rats (n = 54) received daily supplementation of red palm oil (RPO: 0, 2, 4 ml). Subgroups were subsequently injected with saline, cumene hydroperoxide (cHP, 10 µm) or t-butyl hydroperoxide (tbHP, 20 µm) over a 60-day period after which animals were sacrificed. Epididymal sperm motility, concentration, reactive oxygen species (ROS), lipid peroxidation and enzymes were measured. Sperm concentration, motility, superoxide dismutase (SOD) concentration, glutathione (GSH) and catalase (CAT) activities were significantly lower, while dichlorofluorescein (DCF) and malondialdehyde (MDA) were higher in sperm of hydroperoxide-treated animals compared to controls (P < 0.05). DCF and MDA levels were significantly lower, while SOD, CAT and GSH were significantly higher in the sperm of rats supplemented with RPO in combination with hydroperoxide treatment when compared to those receiving hydroperoxide and no RPO supplementation (P < 0.05). Moreover, the DCF, SOD, CAT and GSH levels in the RPO hydroperoxide groups did not differ from control values (P > 0.05). RPO supplementation can successfully attenuate the oxidative stress-induced sperm damage due to organic hydroperoxide exposure. We therefore propose that a daily intake of RPO supplement to the diet might be helpful in protecting males against the adverse effects of high ROS in sperm function and help preserve fertility.

More Elevated Fastballs Associated With Placement on the Injured List due to Shoulder Injury.

Purpose: To evaluate whether impending shoulder injury was associated with changes in pitch location or velocity immediately preceding injury. Methods: Pitchers placed on the injured list (IL) due to a shoulder injury between 2015 and 2020 were identified in the Major League Baseball transactions database. Four-seam fastball velocity and frequency of pitch location for each pitch type was collected for each player in the season before placement on the IL and within 1 month of placement on the IL with a minimum of 55 pitches thrown of 1 type. Pitch locations were collected as identified by Baseball Savant's Game-Day Zones. Game-Day Zones were consolidated into high (above the strike zone midpoint) versus low, arm side (closer to the pitcher's arm side of the plate) versus opposite side, and within the strike zone versus out of zone. Repeated measures analysis of variance determined differences in four-seam velocity and the location distribution of 4-seam fastballs, change-ups, and breaking balls among each group. Results: In total, 267 pitchers were placed on the IL for a shoulder injury with the majority diagnosed with inflammation (89/267) followed by strain or sprain (69/267). Four-seam fastball locations significantly increased above the mid-point of the zone (45.9% vs 42.4%, P = .008) and out of the strike zone (48.5% vs 46.5%, P = .011) within a month before IL placement. There was no significant change in 4-seam fastball velocity immediately before IL placement. Conclusions: Pitchers threw more elevated 4-seam fastballs and out-of-zone 4-seam fastballs in the month before IL placement for shoulder injury. These findings suggest that a loss of 4-seam fastball command decreases with impending shoulder injury. Level of Evidence: IV, prognostic case series.

A Plague of Their Own: Injury Incidence Remains Elevated in the 2021 Major League Baseball Season Compared to Pre-COVID-19 Seasons.

Background: Significant increases in injuries were observed in the 2020 Major League Baseball (MLB) season; these were attributed to an increased acute to chronic workload due to the interrupted preseason and compressed season during the coronavirus disease of 2019 (COVID-19) pandemic. In 2021, the MLB resumed its regular schedule. Hypothesis/Purpose: The purpose of this study was to determine the injury incidence and epidemiology of the 2021 MLB season compared to the injury incidence in the 2020 season and pre-COVID-19 seasons. The hypothesis was that, with the return to normal preseason training, injury incidence in 2021 would return to pre-COVID-19 rates. Additionally, it was hypothesized that injury list (IL) placements at midseason 2021 would be decreased relative to 2020 due to the uninterrupted preseason yet increased at full season 2021 due to increased overall workload from 2020. Study Design: Descriptive epidemiology study. Methods: The MLB transactions database was searched for players placed on the IL between 2018 and 2021. Injuries were categorized by body part and player position. Incidence per 1000 athlete-exposures was calculated for the pre-COVID-19 (2018-2019), 2020, and 2021 seasons. The z test for proportions was used to determine significant differences between injury incidences. Results: The injury incidence rate by midseason 2021 (9.32) compared to 2020 (8.66) was not significantly different (p=0.234). At full season 2021, injury incidence rate (8.69) was significantly higher than pre-COVID-19 seasons (5.13, p<0.001), but not 2020 (p=0.952). When comparing full season 2021 to 2020, increased foot/ankle (0.50 vs 0.14, respectively, p<0.001) and miscellaneous (1.92 vs 0.68, respectively, p<0.001) injuries were observed. Conclusion: The overall injury incidence in 2021 was significantly higher than pre-COVID-19 seasons, and no significant difference was observed between both mid- and full season 2021 and 2020, refuting the hypotheses. This signifies that injury incidence remained elevated in the 2021 season despite resumption of preseason training and a regular season. Level of Evidence: 3.

Return to Sport After Medial Patellofemoral Ligament Reconstruction: A Systematic Review and Meta-analysis.

BACKGROUND: Patellar instability is frequently encountered in the athletic population. Medial patellofemoral ligament (MPFL) reconstruction is a common strategy to treat recurrent patellar dislocation and demonstrates good clinical outcomes. PURPOSE/HYPOTHESIS: The purpose was to examine return to sport after MPFL reconstruction for patellar instability. We hypothesized that patients would resume athletic activity at a high rate and that a large proportion would return to their preoperative level of performance. STUDY DESIGN: Systematic review and meta-analysis. METHODS: A systematic review of the literature was conducted using PubMed and Cochrane Library databases to identify articles reporting return to sport after MPFL reconstruction for recurrent patellar dislocation. Athletes were defined as those reporting a preoperative sport. A random-effects model was used to evaluate return to sport rates, subsequent level, and rate of instability recurrence. Meta-regression was used to compare return to sport rates in patients undergoing MPFL reconstruction without osteotomy compared with those treated with simultaneous tibial tubercle osteotomy or trochleoplasty. RESULTS: In total, 23 articles met inclusion criteria after full-text review. A total of 930 patients were analyzed, including 786 athletes. Women represented 61.3% of all patients. The overall mean age was 21.1 years (range, 9.5-60.0 years), with a mean follow-up time of 3.0 years (range, 0.8-8.5 years). The return to sport rate was 92.8% (95% CI, 86.4-97.6). Patients returned to or surpassed their preoperative level of activity in 71.3% (95% CI, 63.7-78.4) of cases. An osteotomy was performed on 10.5% of athletes. Return to sport did not differ significantly in patients undergoing MPFL reconstruction without osteotomy versus those receiving additional osteotomy (95.4% vs 86.9%; P = .22). Patients returned to sport at a mean of 6.7 months (range, 3.0-6.4 months) postoperatively. Osteotomy did not affect return time. Complications occurred at an overall rate of 8.8%. The most common complication was recurrence of instability (1.9%; 95% CI, 0.4-4.0). The Kujala score was reported by 13 studies, with pre- and postoperative combined means of 60.3 and 90.0, respectively. CONCLUSION: MPFL reconstruction is an effective and reliable treatment in the setting of patellofemoral instability. Surgeons can counsel their patients that they can expect a high rate of return to sport after MPFL reconstruction surgery alone or with concomitant osteotomy.

Hydrostatic pressure effects on a hydrated lipid inverse micellar Fd3m cubic phase.

Over a range of hydration, unsaturated diacylglycerol/phosphatidylcholine mixtures adopt an inverse micellar cubic phase, of crystallographic space group Fd3m. In this study hydrated DOPC:DOG mixtures with a molar ratio close to 1 : 2 were examined as a function of hydrostatic pressure, using synchrotron X-ray diffraction. The small-angle diffraction pattern at atmospheric pressure was used to calculate 2-D sections through the electron density map. Pressure initially has very little effect on the structure of the Fd3m cubic phase, in contrast to its effect on hydrated inverse bicontinuous cubic phases. At close to 2 kbar, a sharp transition occurs from the Fd3m phase to a pair of coexisting phases, an inverse hexagonal H(II) phase plus an (ordered) lamellar phase. Upon increasing the pressure to 3 kbar, a further sharp transition occurs from the H(II) phase to a (fluid) lamellar phase, in coexistence with the ordered lamellar phase. These transitions are fully reversible, but show hysteresis. Remarkably, the lattice parameter of the Fd3m phase is practically independent of pressure. These results show that these two lipids are miscible at low pressure, adopting a single lyotropic phase (Fd3m); they then become immiscible above a critical pressure, phase separating into DOPC-rich and DOG-rich phases.

Association Between Pitch Break on the 4-Seam Fastball and Slider and Shoulder Injury in Major League Baseball Pitchers: A Case-Control Study.

BACKGROUND: Few specific risk factors are known for shoulder injury in professional pitchers. New pitch-tracking data allow for risk stratification based on advanced metrics. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the association between shoulder injury, pitch frequency, and pitch metrics (velocity, total break, break angle, and spin rate) for the 4-seam fastball, curveball, and slider. We hypothesized that more frequent use of the 4-seam fastball would be associated with shoulder injury. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The Major League Baseball (MLB) database was queried for pitchers who had been placed on the injury list (IL) with a shoulder injury between 2015 and 2019. Injured pitchers were matched 1:1 with controls (pitchers not on the IL with a shoulder injury during the study period), based on age (±1 year), history of ulnar collateral ligament reconstruction, position (starter vs reliever), and pitches thrown during the injury season (±500). Pitch frequency, velocity, horizontal break, vertical break, total break, and spin rate for the season were collected from the Baseball Savant website for the 4-seam fastball, curveball, and slider. Univariate analysis was used to determine group differences for individual variables. Multiple logistic regression was performed to determine odds ratios (ORs) for shoulder injury associated with pitch frequency, velocity, total break, break angle, and spin rate. Covariates included age, position, ulnar collateral ligament reconstruction status, expected weighted on-base average, and total pitches thrown. RESULTS: Overall, 233 injured pitchers were evaluated. The most common reason for IL placement was inflammation (78/233; 33.5%) followed by strain or sprain (61/233; 26.2%). Increased total pitch break was associated with an increased risk of shoulder injury for the 4-seam fastball (OR, 1.340 [95% confidence interval (CI), 1.199-1.509]; P < .001) and slider (OR, 1.360 [95% CI, 1.206-1.554]; P < .001). For the slider, a decreased spin rate (OR = 0.998 [95% CI, 0.997-0.999]; P = .026) and a more vertical break angle (OR = 1.170 [95% CI: 1.073-1.278]; P = .004) were associated with increased risk of injury. CONCLUSION: Increased pitch break of the 4-seam fastball and slider was associated positively with shoulder injury in MLB pitchers. These findings add to the understanding of throwing injury and ability to detect risk using ball-tracking technology.