The present study evaluates a new synthetic degradable barrier membrane based on poly(trimethylene carbonate) (PTMC) for use in guided bone regeneration. A collagen membrane and an expanded ...polytetrafluoroethylene (e-PTFE) membrane served as reference materials. In 192 male Sprague–Dawley rats, a standardized 5.0mm circular defect was created in the left mandibular angle. New bone formation was demonstrated by post mortem micro-radiography, micro-computed tomography imaging and histological analysis. Four groups (control, PTMC, collagen, e-PTFE) were evaluated at three time intervals (2, 4 and 12weeks). In the membrane groups the defects were covered; in the control group the defects were left uncovered. Data were analysed using a multiple regression model. In contrast to uncovered mandibular defects, substantial bone healing was observed in defects covered with a barrier membrane. In the latter case, the formation of bone was progressive over 12weeks. No statistically significant differences between the amount of new bone formed under the PTMC membranes and the amount of bone formed under the collagen and e-PTFE membranes were observed. Therefore, it can be concluded that PTMC membranes are well suited for use in guided bone regeneration.
Most seasonal forecasts of Atlantic tropical storm numbers are produced using statistical‐empirical models. However, forecasts can also be made using numerical models which encode the laws of ...physics, here referred to as “dynamical models”. Based on 12 years of re‐forecasts and 2 years of real‐time forecasts, we show that the so‐called EUROSIP (EUROpean Seasonal to Inter‐annual Prediction) multi‐model ensemble of coupled ocean atmosphere models has substantial skill in probabilistic prediction of the number of Atlantic tropical storms. The EUROSIP real‐time forecasts correctly distinguished between the exceptional year of 2005 and the average hurricane year of 2006. These results have implications for the reliability of climate change predictions of tropical cyclone activity using similar dynamically‐based coupled ocean‐atmosphere models.
A Wearable Detector Device (WDD) has been outfitted with Microstructured Semiconductor Neutron Detectors (MSNDs) to aid in the search and localization of special nuclear materials (SNMs). Many SNMs ...decay by spontaneous fission and emit free neutrons. The WDD detects these neutrons and stores interaction rate information to alert the operator to the presence of special nuclear material. The WDD is composed of 16 Modular Neutron Detectors (MNDs), each populated with a 4 × 6 array of 1-cm2 active area, 500-μm thick MSNDs. The individual MSNDs each have an intrinsic thermal-neutron detection efficiency of approximately 30%. Each MND connects to a communications dongle, and the MND and dongle were encased in a 3-in. wide by 5-in. tall by 0.6-in. thick high-density polyethylene moderator (HDPE) case. The 16 MNDs, connected to Controller Area Network dongles, communicate with a master control board, which also contains the battery bank and power conditioning electronics. The operational lifetime of the battery-powered WDD is greater than 12 h per single charge. The WDD, mounted on an ANSI 42.53 phantom, reported 8.12 ± 0.07 cps and 12.93 ± 0.07 cps for a bare and moderated 21.9-ng 252Cf source at a distance of 1 m, respectively. The background count rate was 0.446 ± 0.002 cps. The gamma-ray rejection ratio of the WDD for 137Cs measured at a dose rate of 10 mR/h was 1.8 × 10−8.
•A Wearable Detector Device (WDD) with solid-state neutron detectors was fabricated.•Microstructured Semiconductor Neutron Detectors used in low-power, low-profile WDD.•The WDD’s sensitivity to 252Cf and AmBe was characterized and reported.•Wearable Detector Device response to moving neutron sources was also investigated.
Objective This study compared clinical outcomes of patients receiving CryoValve SG decellularized pulmonary valves with those of patients receiving conventionally processed CryoValve pulmonary ...valves. Methods All consecutive patients undergoing Ross procedures and right ventricular outflow tract reconstructions with SG valves at 7 institutions (February 2000–November 2005) were assessed retrospectively (193 Ross procedures, 149 right ventricular outflow tract reconstructions). Patient, procedural, and outcome data were compared with those from 1246 conventional implants (665 Ross procedures, 581 right ventricular outflow tract reconstructions). Hemodynamic function was assessed at latest follow-up. Results Follow-up was complete for 99% in SG group and 94% in conventional group, with mean follow-ups of 4.0 years (range, 0–6.7 years) for SG and 3.7 years (range, 0–6.7 years) for conventional. Five-year cumulative survivals and freedoms from adverse events were comparable between SG and conventional valves. Among patients undergoing Ross procedures, peak gradient at last follow-up was lower with SG valves ( P < .01); no difference was observed in the right ventricular outflow tract reconstruction population. Pulmonary insufficiency was significantly reduced with SG valves in patients undergoing both Ross procedures ( P < .01) and right ventricular outflow tract reconstructions ( P < .01). Valve type was not a significant predictor of valve-related failure in propensity-adjusted analysis of either procedure. Conclusions CryoValve SG decellularized pulmonary valves have acceptable clinical outcomes and favorably compare with conventionally processed valves. Improved hemodynamic function observed with SG valves could signify improved long-term outcomes and may be due to the decreased antigenicity of these valves.
Storm surge associated with Hurricane Katrina and the breach of levees protecting New Orleans, Louisiana allowed floodwaters from Lake Pontchartrain to inundate 80% of the city. Environmental samples ...were collected during September 16−18, 2005 to determine immediate human and wildlife health hazards from pathogens and toxicants in the floodwaters. Baseline information on potential long-term environmental damage resulting from contaminants in water and sediments pumped into Lake Pontchartrain was also collected. Concentrations of aldrin, arsenic, lead, and seven semivolatile organic compounds in sediments/soils exceeded one or more United States Environmental Protection Agency (USEPA) thresholds for human health soil screening levels and high priority bright line screening levels. High numbers of Aeromonas spp., pathogenic Vibrio spp., and other coliform bacteria were found in floodwater samples. Alligator and snake tissues did not contain excessive toxicant concentrations. Initial findings suggest numerous environmental contaminants are present in New Orleans and support the need for further evaluation of the extent of those threats.
Background. The extent of proximal and distal aortic resection that should be performed for acute type A aortic dissections remains controversial.
Methods. From 1984 to 1999, 119 patients underwent ...repair of an acute type A dissection. Distal resection was to the ascending aorta in 78 (66%) and hemiarch in 41 (34%) patients. Proximally, the aortic valve was preserved in 69 (58%) patients, 40 (34%) underwent composite valve grafting, and 10 (8%) underwent separate graft and valve replacement.
Results. Operative mortality was higher for separate graft and valve (50% ± 16%) than for valve preservation (16% ± 5%) or composite grafts (20% ± 7%) (
p < 0.05). Hemiarch replacement did not increase operative risk compared to distal reconstruction to the ascending aorta (17% ± 6% versus 22% ± 5%,
p > 0.71). At 10 years, freedom from reoperation was 81% ± 7% and long-term survival was 60% ± 8%, but neither was related to the proximal or distal surgical technique (
p > 0.15). Risk factors for late reoperation included a nonresected primary tear and Marfan syndrome (
p < 0.05).
Conclusions. An aggressive surgical approach, including a full root or hemiarch replacement, is not associated with increased operative risk and should be considered when type A dissections extensively involve the valve, sinuses, or arch.
We describe the HadGEM2 family of climate configurations of the Met Office Unified Model, MetUM. The concept of a model "family" comprises a range of specific model configurations incorporating ...different levels of complexity but with a common physical framework. The HadGEM2 family of configurations includes atmosphere and ocean components, with and without a vertical extension to include a well-resolved stratosphere, and an Earth-System (ES) component which includes dynamic vegetation, ocean biology and atmospheric chemistry. The HadGEM2 physical model includes improvements designed to address specific systematic errors encountered in the previous climate configuration, HadGEM1, namely Northern Hemisphere continental temperature biases and tropical sea surface temperature biases and poor variability. Targeting these biases was crucial in order that the ES configuration could represent important biogeochemical climate feedbacks. Detailed descriptions and evaluations of particular HadGEM2 family members are included in a number of other publications, and the discussion here is limited to a summary of the overall performance using a set of model metrics which compare the way in which the various configurations simulate present-day climate and its variability.
Hospitalists are assuming an increasing role in the care of surgical patients, but the impact of this model of care on postoperative outcomes is unknown.
To determine the impact of providing a ...collaborative, hospitalist-led model of care on postoperative outcomes and costs among patients having hip or knee arthroplasty.
Randomized, controlled trial.
Academic medical center.
526 patients having elective orthopedic surgery who are at elevated risk for postoperative morbidity.
Length of stay, inpatient postoperative medical complications, health care provider satisfaction, and inpatient costs.
A comanagement medical Hospitalist-Orthopedic Team compared with standard postoperative care by orthopedic surgeons with medical consultation.
More patients in the hospitalist group were discharged from the hospital with no complications (61.6% vs. 49.8%; difference, 11.8 percentage points 95% CI, 2.8 to 20.7 percentage points). Fewer minor complications were observed among hospitalist patients (30.2% vs. 44.3%; difference, -14.1 percentage points CI, -22.7 to -5.3 percentage points). Observed length of stay was not statistically different between treatment groups. However, when adjusted for discharge delays, mean length of stay for patients in the hospitalist model of care was shorter (5.1 days vs. 5.6 days; difference, -0.5 day CI, -0.8 to -0.1 day). Total costs did not differ between groups. Orthopedic surgeons and nurses preferred the hospitalist model.
Care providers and patients were aware of intervention assignments, and the study could not capture all costs associated with the hospitalist model.
The comanagement medical Hospitalist-Orthopedic Team model reduced minor postoperative complication rates with no statistically significant difference in length of stay or cost. The nurses and surgeons strongly preferred the comanagement hospitalist model. Additional research on the clinical and economic impact of the hospitalist model in other surgical populations is warranted.
Objective To evaluate paracorporeal lung assist devices to treat neonates and children with decompensated respiratory failure as a bridge to recovery or lung transplantation. Methods One neonate (23 ...days old) and 3 young children (aged 2, 9, and 23 months) presented with primary lung disease with pulmonary hypertension, including alveolar capillary dysplasia in 2 and right pulmonary hypoplasia and primary pulmonary hypertension in 1. The patients were listed for lung transplantation but decompensated and required extracorporeal membrane oxygenation (ECMO). The patients were transitioned from ECMO to a pumpless paracorporeal lung assist device (Maquet Quadrox-iD oxygenator in 3, Novalung in 1) with inflow from the pulmonary artery and return to the left atrium. Results The patients were weaned from ECMO and supported by the device for 44 ± 29 days (range, 5-74). Three patients were extubated while supported by the device (after 9, 15, and 72 days). One patient was bridged to lung transplant (9 months old, with alveolar capillary dysplasia, supported 5 days). One patient was bridged to recovery with maximal medical therapy (23 months old, with primary pulmonary hypertension, supported 23 days). Two patients died while awaiting a suitable lung donor after a support time of 54 and 72 days. Conclusions Pediatric patients bridged from ECMO to lung transplantation have poor results. An alternative method for longer term respiratory support was necessary as a bridge for these patients. The use of a paracorporeal lung assist device successfully supported 4 patients to recovery, lung transplantation, or past the average wait time for pediatric donor lungs (27 days). This therapy has the potential to bridge children with decompensated respiratory failure to lung transplantation.
The 2023 report represents a full decade of published annual reports of the American Joint Replacement Registry (AJRR). The number of cases being captured continues to rapidly grow, as are over 3.2 ...million patients included in AJRR. Matched-pair primary and revision data is more robust with 10-year survivorship being available. Similarly, implant-specific survivorship has been included for common implants being used in the United States. The data mined from the AJRR have led to numerous publications and presentations. Numerous trends have emerged, and others have been reinforced with the most recent data. The authors encourage readers to more thoroughly review the full report at the following link: https://www.aaos.org/registries/publications/ajrr-annual-report/.
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