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Mathematical programming techniques have potential applications for water resource management systems. However, these techniques require well-defined objective functions and constraints which complex water resource management systems lack. A proposal is to use these techniques to generate alternative solutions instead. This concept was tested on a wastewater-treatment system which used a minimum-cost programming model. The model used recommended design parameter values in order to simplify the complex design problem. The model then generated alternatives which aided the decision-making process.

Lake Shelbyville, IL, serves as a multifunction reservoir whose operation policy has been affected by unusual weather conditions and water resources development. A modified stochastic dynamic programming (SDP) evaluation model is used to account for unrepeatable agricultural and property damage and promote accuracy of damage estimates. SDP results indicate that definition of a third and fourth period for target operation pool levels in the transition year would improve accuracy of damage estimates. The current estimates for the summer period is sub-optimal but acceptable for the functions of the lake.

This article presents information on the requirements and the implications for the pediatrician of Federal Law PL 99-457. PL 99-457, enacted in 1986, is more than just a number of amendments to PL 94-142, which was enacted in 1975. The older statute is primarily concerned with education issues, and only a relatively small number of the children eligible for special education services have medical problems as the basis for their eligibility. PL 99-457 lowers the mandated coverage to 3 years of age and the discretionary coverage to birth. The younger the child when the handicap is recognized, the greater is the chance that there are major medical ramifications. The early intervention services called for are more likely to have medical rather than educational nuances. Consequently, the medical community must have a greater involvement in all stages of the PL 99-457 development. Historically, pediatricians have played a unique and fundamental role in the care of children with disabilities and their families. It is essential that their extensive experience and insights into the needs and problems of the population to be served by this new law be offered and made available from the pediatric community, be recognized by the professionals in the education community for its depth and import, and be utilized.

Objective: To determine the early impact of the COVID-19 pandemic on breast imaging centers in California and Texas and compare regional differences., Methods: An 11-item survey was emailed to American College of Radiology accredited breast imaging facilities in California and Texas in August 2020. A question subset addressed March-April government restrictions on elective services ("during the shutdown" and "after reopening"). Comparisons were made between states with chi-square and Fisher's tests, and timeframes with McNemar's and paired t-tests., Results: There were 54 respondents (54/240, 23%, 26 California, 28 Texas). Imaging volumes fell during the shutdown and remained below pre-pandemic levels after reopening, with reduction in screening greatest (ultrasound 12% of baseline, mammography 13%, MRI 23%), followed by diagnostic MRI (43%), procedures (44%), and diagnostics (45%). California reported higher volumes during the shutdown (procedures, MRI) and after reopening (diagnostics, procedures, MRI) versus Texas (P = 0.001-0.02). Most screened patients (52/54, 96% symptoms and 42/54, 78% temperatures), and 100% (53/53) modified check-in and check-out. Reading rooms or physician work were altered for social distancing (31/54, 57%). Physician mask (45/48, 94%), gown (15/48, 31%), eyewear (22/48, 46%), and face shield (22/48, 46%) use during procedures increased after reopening versus pre-pandemic (P < 0.001-0.03). Physician (47/54, 87%) and staff (45/53, 85%) financial impacts were common, but none reported terminations., Conclusion: Breast imaging volumes during the early pandemic fell more severely in Texas than in California. Safety measures and financial impacts on physicians and staff were similar in both states., (© Society of Breast Imaging 2021. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To determine the impact of the COVID-19 pandemic on breast imaging education., Methods: A 22-item survey addressing four themes during the early pandemic (time on service, structured education, clinical training, future plans) was emailed to Society of Breast Imaging members and members-in-training in July 2020. Responses were compared using McNemar's and Mann-Whitney U tests; a general linear model was used for multivariate analysis., Results: Of 136 responses (136/2824, 4.8%), 96 U.S. responses from radiologists with trainees, residents, and fellows were included. Clinical exposure declined during the early pandemic, with almost no medical students on service (66/67, 99%) and fewer clinical days for residents (78/89, 88%) and fellows (48/68, 71%). Conferences shifted to remote live format (57/78, 73%), with some canceled (15/78, 19%). Compared to pre-pandemic, resident diagnostic (75/78, 96% vs 26/78, 33%) ( P < 0.001) and procedural (73/78, 94% vs 21/78, 27%) ( P < 0.001) participation fell, as did fellow diagnostic (60/61, 98% vs 47/61, 77%) ( P = 0.001) and procedural (60/61, 98% vs 43/61, 70%) ( P < 0.001) participation. Most thought that the pandemic negatively influenced resident and fellow screening (64/77, 83% and 43/60, 72%, respectively), diagnostic (66/77, 86% and 37/60, 62%), and procedural (71/77, 92% and 37/61, 61%) education. However, a majority thought that decreased time on service (36/67, 54%) and patient contact (46/79, 58%) would not change residents' pursuit of a breast imaging fellowship., Conclusion: The pandemic has had a largely negative impact on breast imaging education, with reduction in exposure to all aspects of breast imaging. However, this may not affect career decisions., (© Society of Breast Imaging 2021. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Morbidly obese women are at increased risk for breast cancer, and the majority of surgical weight-loss patients are older than 40 years old., Objective: The purpose of the present study was to determine the technical and interpretive changes in mammography following bariatric surgery., Setting: Accredited Academic Hospital., Methods: Two breast-imaging radiologists reviewed screening mammograms performed on 10 morbidly obese women undergoing bariatric surgery both pre- and postoperatively. American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS) density, imaging quality measurements, compression force, breast thickness, pectoral nipple line (PNL) length, and x-ray beam kilovoltage (kVp) and miliamperes per second (mAs) were recorded., Results: The average patient age was 56 years old, with mean age at menarche of 13 years old; 70% of patients were postmenopausal (average age 49 years at menopause) and 50% had a family history of breast cancer. There was a significant reduction in both BMI (-13.2 kg/m 2 , P<.01) and waist circumference (-32.0 cm, P<.01) following bariatric surgery. There was a significant reduction in breast thickness (-23.8 mm), reduction in PNL length (-1.9 cm), reduction in kVp (-1.2), and reduction in mAs (-16.7) even though there was no compression force change in pre- and postoperative mammograms detected. All breast densities were fatty or scattered though there were more scattered and fewer fatty images after surgery (P = .002)., Conclusion: Morbidly obese women can undergo quality mammograms before and after bariatric surgery; however, weight loss after bariatric surgery leads to only slightly denser mammograms. Furthermore, weight loss reduces mammographic radiation doses., (Copyright © 2017 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: To examine the relationship between hospital volume and in-hospital adverse events., Data Sources: Patient safety indicator (PSI) was used to identify hospital-acquired adverse events in the Nationwide Inpatient Sample database in abdominal aortic aneurysm, coronary artery bypass graft, and Roux-en-Y gastric bypass from 2005 to 2008., Study Design: In this observational study, volume thresholds were defined by mean year-specific terciles. PSI risk-adjusted rates were analyzed by volume tercile for each procedure., Principal Findings: Overall, hospital volume was inversely related to preventable adverse events. High-volume hospitals had significantly lower risk-adjusted PSI rates compared to lower volume hospitals (p < .05)., Conclusion: These data support the relationship between hospital volume and quality health care delivery in select surgical cases. This study highlights differences between hospital volume and risk-adjusted PSI rates for three common surgical procedures and highlights areas of focus for future studies to identify pathways to reduce hospital-acquired events., (© Health Research and Educational Trust.)

Context: Emphasis has been placed on quality and patient safety in medicine; however, little is known about whether quality over time has actually improved in areas such as patient safety indicators (PSIs)., Objective: To determine whether national trends for hospital PSIs have improved from 1998 to 2007., Design, Setting, and Participants: Using PSI criteria from the Agency for Healthcare Research and Quality, PSIs were identified in the Nationwide Inpatient Sample (NIS) for all eligible inpatient admissions between 1998 and 2007. Joinpoint regression was used to estimate annual percentage changes (APCs) for PSIs., Main Outcome Measure: Annual percent change for PSIs., Results: From 1998 to 2007, 7.6 million PSI events occurred for over 69 million hospitalizations. A total of 14 PSIs showed statistically significant trends. Seven PSIs had increasing APC: postoperative pulmonary embolism or deep vein thrombosis (8.94), postoperative physiological or metabolic derangement (7.67), postoperative sepsis (7.17), selected infections due to medical care (4.05), decubitus ulcer (3.05), accidental puncture or laceration (2.64), and postoperative respiratory failure (1.46). Seven PSIs showed decreasing APCs: birth trauma injury to neonate (-17.79), failure to rescue (-6.05), postoperative hip fracture (-5.86), obstetric trauma-vaginal without instrument (-5.69), obstetric trauma-vaginal with instrument (-4.11), iatrogenic pneumothorax (-2.5), and postoperative wound dehiscence (-1.8)., Conclusion: This is the first study to establish national trends of PSIs during the past decade indicating areas for potential quality improvement prioritization. While many factors influence these trends, the results indicate opportunities for either emulation or elimination of current patient safety trends., (© Health Research and Educational Trust.)

Background: Clinical variables may identify a subset of patients with pediatric-onset ulcerative colitis (UC) (≤18 years at diagnosis) at risk for adverse outcomes. We postulated that routinely measured clinical variables measured at diagnosis would predict colectomy in patients with pediatric-onset UC., Methods: We conducted a chart review of patients with pediatric-onset UC at a single center over a 10-year period. We compared patients with and without colectomy across several variables, used proportional hazards regression to adjust for potential confounders, and assessed the ability of a UC risk score to predict colectomy., Results: Among 470 patients with inflammatory bowel disease ICD9-coded encounters, 155 patients had UC and 135 were eligible for analysis. The 1- and 3-year colectomy rates were 16.7% (95% confidence interval [CI]: 11.0%-24.8%) and 35.6% (26.7%-45.4%). White blood cell (WBC) count and hematocrit measured at diagnosis were associated with colectomy at 3 years, even after correcting for potential confounding variables. A UC Risk Score derived from the WBC count and hematocrit was strongly associated with colectomy risk, with a high negative predictive value (NPV) for colectomy at 1 and 3 years (NPV = 0.95 and 0.89, respectively), but low positive predictive value (PPV = 0.22 and 0.38, respectively)., Conclusions: A risk score calculated from WBC and hematocrit measured at diagnosis was associated with, but incompletely predictive of, colectomy in pediatric-onset UC. These data suggest 1) routinely measured clinical variables may have a prognostic role in risk stratification, and 2) multicenter prospective studies are needed to optimize risk stratification in pediatric UC. Our findings have impact on the design of such studies., (Copyright © 2010 Crohn's & Colitis Foundation of America, Inc.)

Introduction: Roux-en-Y gastric bypass (RNYGB) surgery offers an effective and enduring treatment for morbid obesity. Gastric bypass may alter gastrointestinal (GI) flora possibly resulting in bacterial overgrowth and dysmotility. Our hypothesis was that daily use of probiotics would improve GI outcomes after RNYGB., Methods: Forty-four patients undergoing RNYGB were randomized to either a probiotic or control group; 2.4 billion colonies of Lactobacillus were administered daily postoperatively to the probiotic group. The outcomes of H(2) levels indicative of bacterial overgrowth, GI-related quality of life (GIQoL), serologies, and weight loss were measured preoperatively and at 3 and 6 months postoperatively. Categorical variables were analyzed by chi(2) test and continuous variables were analyzed by t test with a p < 0.05 for significance., Results: At 6 months, a statistically significant reduction in bacterial overgrowth was achieved in the probiotic group with a preoperative to postoperative change of sum H(2) part per million (probiotics = -32.13, controls = 0.80). Surprisingly, the probiotic group attained significantly greater percent excess weight loss than that of control group at 6 weeks (controls = 25.5%, probiotic = 29.9%) and 3 months (38.55%, 47.68%). This trend also continued but was not significant at 6 months (60.78%, 67.15%). The probiotic group had significantly higher postoperative vitamin B12 levels than the control group. Both probiotic and control groups significantly improved their GIQoL., Conclusion: In this novel study, probiotic administration improves bacterial overgrowth, vitamin B12 availability, and weight loss after RNYGB. These data may provide further evidence that altering the GI microbiota can influence weight loss.

The management of tropospheric ozone (O3) is particularly difficult. The formulation of emission control strategies requires considerable information including: (1) emission inventories, (2) available control technologies, (3) meteorological data for critical design episodes, and (4) computer models that simulate atmospheric transport and chemistry. The simultaneous consideration of this information during control strategy design can be exceedingly difficult for a decision-maker. Traditional management approaches do not explicitly address cost minimization. This study presents a new approach for designing air quality management strategies; a simple air quality model is used conjunctively with a complex air quality model to obtain low-cost management strategies. A simple air quality model is used to identify potentially good solutions, and two heuristic methods are used to identify cost-effective control strategies using only a small number of simple air quality model simulations. Subsequently, the resulting strategies are verified and refined using a complex air quality model. The use of this approach may greatly reduce the number of complex air quality model runs that are required. An important component of this heuristic design framework is the use of the simple air quality model as a screening and exploratory tool. To achieve similar results with the simple and complex air

We model functions that use genetic information as input and trait information as output to understand genetic linkage in complex diseases. Using simulated data from GAW11, we have applied categorical classification methods and neural network analysis. We use sharing at selected markers as input, and the classification of the sib pair (for example, affected-affected or affected-unaffected) as output. In addition, our methods include environmental risk factors as predictors of phenotype. Categorical and neural network methods each led to results consistent with findings from other methods such as the logistic regression method of Rice et al. [this issue]. Post-analysis comparison with the GAW11 answers showed that these methods are capable of detecting correct signals in a single replicate. One advantage of our methods is that they allow analysis of the entire genome at once, so that interactions among multiple trait-influencing loci may be detected. Furthermore, these methods can use a variety of sib pairs rather than affected pairs only.

Extramucosal pyloromyotomy is a method with predictable morbidity and outcome for the cure of infantile hypertrophic pyloric stenosis. The method created by Ramstedt is successfully performed using a laparoscopic approach. Preliminary reports, including 266 cases treated by laparoscopic pyloromyotomy (LP), suggest that morbidity is comparable to that of open approaches. Advantages of LP include superior cosmetic result and no reported wound infections to date. For the experienced laparoscopic surgeon, LP is an precise and efficient technique, and the preferred method for the management of infantile hypertrophic pyloric stenosis.

Background: Patients often undergo limited resection instead of lobectomy for non-small cell lung cancer because of a low preoperative forced expiratory volume in 1 second (FEV1). Our goal is to define criteria that will preoperatively identify a group of patients who will not lose further function after lobectomy., Methods: Patients who underwent lobectomy with a preoperative FEV1 of less than 80% of predicted were retrospectively identified. Data collected included preoperative and postoperative pulmonary function tests, age, sex, the lobe resected, and preoperative ventilation-perfusion scan result., Results: Thirty-two patients were included in this study. The median preoperative FEV1 was 60% of predicted (1.65 L) and the mean change in FEV1 was a loss of 7.8% after lobectomy. The patients were divided into two groups. Group 1 (n = 13) had a preoperative FEV1 of less than or equal to 60% of predicted (median, 49%; 1.35 L) combined with an FEV1 to forced vital capacity ratio of less than or equal to 0.6. Group 2 (n = 19) includes all other patients (median preoperative FEV1, 69% of predicted; 1.87 L). The mean changes in FEV1 after lobectomy were +3.7% and -15.7% for groups 1 and 2, respectively (p < 0.005). A chronic obstructive pulmonary disease index was defined and then calculated for each patient. The relationship between this index and the change in FEV1 after lobectomy for all 32 patients appears linear (r = -0.43; p = 0.015)., Conclusions: Patients with a very low preoperative FEV1 and FEV1 to forced vital capacity ratio are less likely to lose ventilatory function after lobectomy and may actually improve it.

Objectives: Traumatic loss of significant lengths of ureter all too often results in nephrectomy when vascularized pedicles of bowel or bladder fail or are not available for substitution. Historically, alloplastic replacement of ureters has failed due to obstruction, bioincompatibility, or graft migration. This study was undertaken to test the performance of ringed expanded polytetrafluoroethylene (PTFE) tube grafts as ureteral replacements in a canine model., Methods: Eight female dogs underwent partial ureteral replacement with ringed PTFE tube grafts. An involuting anastomosis was used to anchor the graft to the bladder. The dogs were followed with intravenous urograms and Whitaker infusion pressure tests for up to 12 months., Results: Six of 8 animals (75%) had preservation of excellent renal function with normal intravenous urograms and low Whitaker infusion pressures. One animal had mild hydronephrosis with an elevated infusion pressure. One animal died of spontaneous renal rupture secondary to obstruction at the ureteral-graft anastomosis. All other grafts were patent by histologic examination without encrustation or infection., Conclusions: Although not suggested as first-line therapy after ureteral loss, expanded PTFE may have a use as a prosthetic ureteral replacement in situations where conventional surgical therapies are unsuccessful. This material appears to be biocompatible, and the technique of bladder anastomosis described here prevented migration of the prosthesis.