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Economic hardship is a major threat to children's health, implying that pediatric out-of-hospital cardiac arrest (pOHCA) might be promoted by lower incomes and child poverty. To target resources, it is helpful to identify geographical hotspots. Rhode Island is the smallest state by area in the United States of America. It has one million inhabitants and is comparable to many larger cities worldwide. We aimed to investigate the possible associations of pOHCA with economic factors and the coronavirus 2019 (COVID-19) pandemic. Our goal was to identify high-risk areas and evaluate whether the COVID-19 pandemic had an influence on delays in prehospital care. We analyzed all pOHCA cases (patients <18 years of age) in Rhode Island between March 1, 2018-February 28, 2022. We performed Poisson regression with pOHCA as dependent and economic risk factors (median household income [MHI] and child poverty rate from the US Census Bureau) as well as the COVID-19 pandemic as independent variables. Hotspots were identified using local indicators of spatial association (LISA) statistics. We used linear regression to assess the association of emergency nedical services-related times with economic risk factors and COVID-19. A total of 51 cases met our inclusion criteria. Lower MHIs (incidence-rate ratio [IRR]) 0.99 per $1,000 MHI; P=0.01) and higher child poverty rates (IRR 1.02 per percent; P=0.02) were significantly associated with higher numbers of ambulance calls due to pOHCA. The pandemic did not have a significant influence (IRR 1.1; P=0.7). LISA identified 12 census tracts as hotspots (P<0.01). The pandemic was not associated with delays in prehospital care. Lower median household income and higher child poverty rate are associated with higher numbers of pediatric out-of-hospital cardiac arrest.

Unlike optical CCDs, near-infrared detectors, which are based on CMOS hybrid readout technology, typically suffer from electrical crosstalk between the pixels. The interpixel capacitance (IPC) responsible for the crosstalk affects the point-spread function (PSF) of the telescope, increasing the size and modifying the shape of all objects in the images while correlating the Poisson noise. Upcoming weak lensing surveys that use these detectors, such as WFIRST, place stringent requirements on the PSF size and shape (and the level at which these are known), which in turn must be translated into requirements on IPC. To facilitate this process, we present a first study of the effect of IPC on WFIRST PSF sizes and shapes. Realistic PSFs are forward-simulated from physical principles for each WFIRST bandpass. We explore how the PSF size and shape depends on the range of IPC coupling with pixels that are connected along an edge or corner; for the expected level of IPC in WFIRST, IPC increases the PSF sizes by ∼5%. We present a linear fitting formula that describes the uncertainty in the PSF size or shape due to uncertainty in the IPC, which could arise for example due to unknown time evolution of IPC as the detectors age or due to spatial variation of IPC across the detector. We also study of the effect of a small anisotropy in the IPC, which further modifies the PSF shapes. Our results are a first, critical step in determining the hardware and characterization requirements for the detectors used in the WFIRST survey.

Background: Infectious diseases, including COVID-19, have a severe impact on child health globally. We investigated whether emergency medical service (EMS) calls are a bellwether for future COVID-19 caseloads. We elaborated on geographical hotspots and socioeconomic risk factors. Methods: All EMS calls for suspected infectious disease in the pediatric population (under 18 years of age) in Rhode Island between 1 March 2018 and 28 February 2022 were included in this quasi-experimental ecological study. The first of March 2020 was the beginning of the COVID-19 pandemic. We used the 2020 census tract and the most recent COVID-19 data. We investigated associations between pediatric EMS calls and positive COVID-19 tests with time series analysis and identified geographical clusters using local indicators of spatial association. Economic risk factors were examined using Poisson regression. Results: We included 980 pediatric ambulance calls. Calls during the omicron wave were significantly associated with increases in positive COVID-19 tests one week later (p < 0.001). Lower median household income (IRR 0.99, 95% CI [0.99, 0.99]; p < 0.001) and a higher child poverty rate (IRR 1.02, 95% CI [1.02, 1.02]; p < 0.001) were associated with increased EMS calls. Neighborhood hotspots changed over time. Conclusion: Ambulance calls might be a predictor for major surges of COVID-19 in children.

In April 2023, the superBIT telescope was lifted to the Earth’s stratosphere by a helium-filled super-pressure balloon to acquire astronomical imaging from above (99.5% of) the Earth’s atmosphere. It was launched from New Zealand and then, for 40 days, circumnavigated the globe five times at a latitude 40 to 50 degrees south. Attached to the telescope were four “drs” (Data Recovery System) capsules containing 5 TB solid state data storage, plus a gnss receiver, Iridium transmitter, and parachute. Data from the telescope were copied to these, and two were dropped over Argentina. They drifted 61 km horizontally while they descended 32 km, but we predicted their descent vectors within 2.4 km: in this location, the discrepancy appears irreducible below ∼2 km because of high speed, gusty winds and local topography. The capsules then reported their own locations within a few metres. We recovered the capsules and successfully retrieved all of superBIT’s data despite the telescope itself being later destroyed on landing.

We examine the effects of charge transfer inefficiency (CTI) during CCD readout on the demanding galaxy shape measurements required by studies of weak gravitational lensing. We simulate a CCD readout with CTI such as that caused by charged particle radiation damage in space-based detectors. We verify our simulations on real data from fully depleted p-channel CCDs that have been deliberately irradiated in a laboratory. We show that only charge traps with time constants of the same order as the time between row transfers during readout affect galaxy shape measurements. We simulate deep astronomical images and the process of CCD readout, characterizing the effects of CTI on various galaxy populations. Our code and methods are general and can be applied to any CCDs, once the density and characteristic release times of their charge trap species are known. We baseline our study around p-channel CCDs that have been shown to have charge transfer efficiency up to an order of magnitude better than several models of n-channel CCDs designed for space applications. We predict that for galaxies furthest from the readout registers, bias in the measurement of galaxy shapes,Δe Δ e , will increase at a rate of(2.65 ± 0.02) × 10-4 yr-1 ( 2.65 ± 0.02 ) × 10 - 4   y r - 1 at L2 for accumulated radiation exposure averaged over the solar cycle. If uncorrected, this will consume the entire shape measurement error budget of a dark energy mission surveying the entire extragalactic sky within about 4 yr of accumulated radiation damage. However, software mitigation techniques demonstrated elsewhere can reduce this by a factor of∼10 ∼ 10 , bringing the effect well below mission requirements. This conclusion is valid only for the p-channel CCDs we have modeled; CCDs with higher CTI will fare worse and may not meet the requirements of future dark energy missions. We also discuss additional ways in which hardware could be designed to further minimize the impact of CTI.

Background: Tibial spine fractures (TSFs) are typically treated nonoperatively when nondisplaced and operatively when completely displaced. However, it is unclear whether displaced but hinged (type 2) TSFs should be treated operatively or nonoperatively. Purpose: To compare operative versus nonoperative treatment of type 2 TSFs in terms of overall complication rate, ligamentous laxity, knee range of motion, and rate of subsequent operation. Study Design: Cohort study; Level of evidence, 3. Methods: We reviewed 164 type 2 TSFs in patients aged 6 to 16 years treated between January 1, 2000, and January 31, 2019. Excluded were patients with previous TSFs, anterior cruciate ligament (ACL) injury, femoral or tibial fractures, or grade 2 or 3 injury of the collateral ligaments or posterior cruciate ligament. Patients were placed according to treatment into the operative group (n = 123) or nonoperative group (n = 41). The only patient characteristic that differed between groups was body mass index (22 [nonoperative] vs 20 [operative]; P = .02). Duration of follow-up was longer in the operative versus the nonoperative group (11 vs 6.9 months). At final follow-up, 74% of all patients had recorded laxity examinations. Results: At final follow-up, the nonoperative group had more ACL laxity than did the operative group (P < .01). Groups did not differ significantly in overall complication rate, reoperation rate, or total range of motion (all, P > .05). The nonoperative group had a higher rate of subsequent new TSFs and ACL injuries requiring surgery (4.9%) when compared with the operative group (0%; P = .01). The operative group had a higher rate of arthrofibrosis (8.9%) than did the nonoperative group (0%; P = .047). Reoperation was most common for hardware removal (14%), lysis of adhesions (6.5%), and manipulation under anesthesia (6.5%). Conclusion: Although complication rates were similar between nonoperatively and operatively treated type 2 TSFs, patients treated nonoperatively had higher rates of residual laxity and subsequent tibial spine and ACL surgery, whereas patients treated operatively had a higher rate of arthrofibrosis. These findings should be considered when treating patients with type 2 TSF.

Background: The uncommon nature of tibial spine fractures (TSFs) may result in delayed diagnosis and treatment. The outcomes of delayed surgery are unknown. Purpose: To evaluate risk factors for, and outcomes of, delayed surgical treatment of pediatric TSFs. Study Design: Cohort study; Level of evidence, 3. Methods: The authors performed a retrospective cohort study of TSFs treated surgically at 10 institutions between 2000 and 2019. Patient characteristics and preoperative data were collected, as were intraoperative information and postoperative complications. Surgery ≥21 days after injury was considered delayed based on visualized trends in the data. Univariate analysis was followed by purposeful entry multivariate regression to adjust for confounders. Results: A total of 368 patients (mean age, 11.7 ± 2.9 years) were included, 21.2% of whom underwent surgery ≥21 days after injury. Patients who experienced delayed surgery had 3.8 times higher odds of being diagnosed with a TSF at ≥1 weeks after injury (95% CI, 1.1-14.3; P = .04), 2.1 times higher odds of having seen multiple clinicians before the treating surgeon (95% CI, 1.1-4.1; P = .03), 5.8 times higher odds of having magnetic resonance imaging (MRI) ≥1 weeks after injury (95% CI, 1.6-20.8; P < .007), and were 2.2 times more likely to have public insurance (95% CI, 1.3-3.9; P = .005). Meniscal injuries were encountered intraoperatively in 42.3% of patients with delayed surgery versus 21.0% of patients treated without delay (P < .001), resulting in 2.8 times higher odds in multivariate analysis (95% CI, 1.6-5.0; P < .001). Delayed surgery was also a risk factor for procedure duration >2.5 hours (odds ratio, 3.3; 95% CI, 1.4-7.9; P = .006). Patients who experienced delayed surgery and also had an operation >2.5 hours had 3.7 times higher odds of developing arthrofibrosis (95% CI, 1.1-12.5; P = .03). Conclusion: Patients who underwent delayed surgery for TSFs were found to have a higher rate of concomitant meniscal injury, longer procedure duration, and more postoperative arthrofibrosis when the surgery length was >2.5 hours. Those who experienced delays in diagnosis or MRI, saw multiple clinicians, and had public insurance were more likely to have a delay to surgery.

Background: Operative treatment of displaced tibial spine fractures consists of fixation and reduction of the fragment in addition to restoring tension of the anterior cruciate ligament. Purpose: To determine whether residual displacement of the anterior portion of a tibial spine fragment affects the range of motion (ROM) or laxity in operatively and nonoperatively treated patients. Study Design: Cohort study; Level of evidence, 3. Methods: Data were gathered from 328 patients younger than 18 years who were treated for tibial spine fractures between 2000 and 2019 at 10 institutions. ROM and anterior lip displacement (ALD) measurements were summarized and compared from pretreatment to final follow-up. ALD measurements were categorized as excellent (0 to <1 mm), good (1 to <3 mm), fair (3 to 5 mm), or poor (>5 mm). Posttreatment residual laxity and arthrofibrosis were assessed. Results: Overall, 88% of patients (290/328) underwent operative treatment. The median follow-up was 8.1 months (range, 3-152 months) for the operative group and 6.7 months (range, 3-72 months) for the nonoperative group. The median ALD measurement of the cohort was 6 mm pretreatment, decreasing to 0 mm after treatment (P < .001). At final follow-up, 62% of all patients (203/328) had excellent ALD measurements, compared with 5% (12/264) before treatment. Subjective laxity was seen in 11% of the nonoperative group (4/37) and 5% of the operative group (15/285; P = .25). Across the cohort, there was no association between final knee ROM and final ALD category. While there were more patients with arthrofibrosis in the operative group (7%) compared with the nonoperative group (3%) (P = .49), this was not different across the ALD displacement categories. Conclusion: Residual ALD was not associated with posttreatment subjective residual laxity, extension loss, or flexion loss. The results suggest that anatomic reduction of a tibial spine fracture may not be mandatory if knee stability and functional ROM are achieved.

Epiphysiodesis is performed to treat leg-length discrepancies and angular deformities in children. However, when placed across a physis to modulate growth, screws can bend or break postoperatively. This study evaluated the mechanical properties of 3 different screw designs commonly used when performing an epiphysiodesis. Six 4.0-mm cannulated, fully threaded; six 4.0-mm cannulated, partially threaded; and six 4.0-mm noncannulated, partially threaded cancellous screws underwent cantilever bending and tension testing in a simulated physis. All screws were tested in simulated cancellous bone foam blocks. All testing was performed using a servo-hydraulic testing machine to determine stiffness and ultimate load. For statistical analysis, one-way analysis of variance with Tukey's honestly significant difference test in post hoc analysis was used to assess significant differences among groups ( P <.05). The noncannulated, partially threaded screws had a significantly lower stiffness than the 2 cannulated screw types in the tension test ( P <.001) and bending test ( P <.001). Additionally, the noncannulated, partially threaded screws had significantly higher ultimate load to failure than the 2 cannulated screw types in the tension test ( P <.001) and the cannulated, partially threaded screws in the bending test ( P =.045). The results indicate that noncannulated, partially threaded screws have a higher ultimate load capacity and are less stiff than both cannulated, partially threaded screws and cannulated, fully threaded screws. Surgeons should take into consideration that noncannulated, partially threaded screws are less likely to fail following epiphysiodesis. [ Orthopedics. 2018; 41(2):e240–e244.]

Background: The uncommon nature of tibial spine fractures may result in delayed presentation, diagnosis, and treatment. Elucidation of the contributing factors to such delays may provide an opportunity to improve patient care. Additionally, the outcomes of delayed surgery are unknown. Hypothesis/Purpose: The purpose of this study is to evaluate risk factors for, and consequences of, delayed surgical treatment of pediatric tibial spine fractures. Methods: We performed a retrospective cohort study of tibial spine fractures treated surgically at 10 institutions between 2000 and 2019. Demographic and pre-operative data were collected, as was intra-operative information and post-operative complications. Attention was focused on delays in evaluation and treatment, which were treated as both continuous and categorical variables. Surgery ≥21 days after injury was considered “delayed”. Univariate analysis was followed by purposeful entry multivariate regression to adjust for confounding factors. Results: A total of 368 subjects (mean age 11.7±2.9 years) were included, 21.2% of which underwent surgery ≥21 days after injury. Patients who experienced delayed surgery had 3.8 times higher odds of being diagnosed with a TSF 1 or more weeks after injury [95% confidence interval (CI) 1.1-14.3, p=0.04], 2.3 times higher odds of having seen multiple clinicians prior to the treating surgeon (95% CI 1.1-4.8, p=0.02), 5.8 times higher odds of having magnetic resonance imaging 1 or more weeks after injury (MRI; 95% CI 1.6-20.8, p<0.007), and were 2.4 times more likely to have public insurance (95% CI 1.3-4.2, p=0.003). Meniscal injuries were encountered intra-operatively in 42.3% of those that had delayed surgery compared to 16.6% of patients that did not (p<0.001), resulting in 2.8 times higher odds in multivariate analysis (95% CI 1.6-5.0, p<0.001). Delayed surgery was also a risk factor for procedure duration longer than 2.5 hours (odds ratio 3.3, 95% CI 1.4-7.9; p=0.006). Patients who experienced delayed surgical management and an operation longer than 2.5 hours had 3.7 times higher odds of developing arthrofibrosis (95% CI 1.1-12.5, p=0.03). Conclusion: When surgery for a TSF was performed ≥21 days after injury, patients were at increased risk for concomitant meniscal pathology, longer case duration, and possibly post-operative arthrofibrosis. Those who experienced delays in diagnosis or MRI, saw multiple clinicians, and had public insurance were more likely to have a delay to surgery. These results provide an opportunity to optimize care for children that are at highest risk for delayed treatment.