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Abstract Commercial backsheets based on polyvinylidene fluoride (PVDF) can experience premature field failures in the form of outer layer cracking. This work seeks to provide a better understanding of the changes in material properties that lead to crack formation and find appropriate accelerated tests to replicate them. The PVDF-based backsheet outer layer can have a different structure and composition, and is often blended with a poly(methyl methacrylate) (PMMA) polymer. We observed depletion of PMMA upon aging with sequential (MAST) and combined (C-AST) accelerated stress testing. In field-aged samples from Arizona and India, where PVDF crystallizes in its predominant α-phase, the degree of crystallinity greatly increased. MAST and C-AST protocols were, to some extent, able to replicate the increase in crystallinity seen in PVDF after ~ 7 years in the field, but no single-stress test condition (UV, damp heat, thermal cycling) resulted in significant changes in the material properties. The MAST regimen used here was too extreme to produce realistic degradation, but the test was useful in discovering weaknesses of the particular PVDF-based outer layer structure studied. No excessive β-phase formation was observed after aging with any test condition; however, the presence of β-phase was identified locally by Fourier transform infrared spectroscopy (FTIR). We conclude that both MAST and C-AST are relevant tests for screening outdoor failure mechanisms in PVDF backsheets, as they were successful in producing material degradation that led to cracking.

Abstract Novel methods for advancing reliability testing of photovoltaic (PV) modules and materials have recently been developed. Combined-accelerated stress testing (C-AST) is one such method which has demonstrated reliable reproduction of some field-failures which were not reproducible by standard certification tests. To increase confidence and assist in the development of C-AST, and other new testing protocols, it is important to validate that the failure modes observed and mechanisms induced are representative of those observed in the field, and not the product of unrealistic stress conditions. Here we outline a method using appropriate materials characterization and modelling to validate the failure mechanisms induced in C-AST such that we can increase confidence in the test protocol. The method is demonstrated by applying it to a known cracking failure of a specific polyamide (PA)-based backsheet material. We found that the failure of the PA-based backsheet was a result of a combination of stress factors. Photo-oxidation from ultra-violet (UV) radiation exposure caused a reduction in fracture toughness, which ultimately lead to the cracking failure. We show that the chemical and structural changes observed in the backsheet following C-AST aging were also observed in field-aged samples. These results increase confidence that the conditions applied in C-AST are representative of the field and demonstrates our approach to validating the failure mechanisms induced.

Abstract Objectives This study evaluates aerosol production with high‐flow nasal cannula (HFNC) and noninvasive positive pressure ventilation (NIPPV) compared to 6 L/min by low‐flow nasal cannula. Methods Two healthy volunteers were randomized to control (6 L/min by low‐flow nasal cannula), NIPPV, or HFNC using block randomization. NIPPV conditions were studied using continuous positive airway pressures of 5, 10, and 15 cm H2O with an FiO2 of 1.0 delivered via full‐face mask. HFNC conditions included flow rates of 30 and 40 L/min with an FiO2 of 1.0 with and without coughing. HFNC and low‐flow nasal cannula conditions were repeated with and without participants wearing a surgical mask. Six aerosol sizes (0.3, 1.0, 2.5, 5, and 10 µm) and total aerosol mass were measured at 2 and 6 ft from the participant's nasopharynx. Results There was no significant difference in aerosol production between either HFNC or NIPPV and control. There was also no significant difference with the use of a procedural mask over the HFNC. There was significant variation between the 2 participants, but in neither case was there a difference compared to control. There was an aerosol‐time trend, but there does not appear to be a difference between either flow rate, pressure, or control. Furthermore, there was no accumulation of total aerosol particles over the total duration of the experiment in both HFNC and NIPPV conditions. Conclusions HFNC and NIPPV did not increase aerosol production compared to 6 L/min by low‐flow nasal cannula in this experiment involving healthy volunteers.

Abstract Background The Hospital Readmission Reduction Program (HRRP) penalizes hospitals for high all-cause unplanned readmission rates. Many have expressed concern that hospitals serving patient populations with more comorbidities, lower incomes, and worse self-reported health status may be disproportionately penalized by readmissions that are not clinically related to the index admission. The impact of including clinically unrelated readmissions on hospital performance is largely unknown. We sought to determine if a clinically related readmission measure would significantly alter the assessment of hospital performance. Methods We analyzed Medicare claims for beneficiaries in Michigan admitted for pneumonia and joint replacement from 2011 to 2013. We compared each hospital’s 30-day readmission rate using specifications from the HRRP’s all-cause unplanned readmission measure to values calculated using a clinically related readmission measure. Results We found that the mean 30-day readmission rates were lower when calculated using the clinically related readmission measure (joint replacement: all-cause 5.8%, clinically related 4.9%, p

Objective: To better evaluate tertiary Gleason pattern reporting and to evaluate the impact of tertiary Gleason pattern 5 (TP5) on prostate cancer pathological features and biochemical recurrence at our large single institution. Methods: We retrospectively reviewed 1962 patients who underwent radical prostatectomy (RP) for prostate cancer; TP5 was reported in 159 cases (8.1%). Men with Gleason score (GS) 7 and GS 8 disease were divided into subgroups with and without TP5, and histopathological features were compared. Multivariate analyses were conducted to assess the impact on TP5 on biochemical-free survival (BFS). Results: Tumors possessing GS 3 + 4 with TP5 were more likely to exhibit extraprostatic extension (EPE) and had a larger tumor diameter (TD) than GS 3 + 4 alone. GS 3 + 4 with TP5 was also associated with positive surgical margins (SM), seminal vesicle involvement (SVI), and higher pre-operative prostate-specific antigen (PSA) values, but without statistical significance. GS 4 + 3 with TP5 more commonly presented with EPE, positive SM, SVI, and greater TD and pre-operative PSA level than GS 4 + 3 alone. In multivariate analysis, Gleason score, EPE, and TP5 were overall independent risk factors for PSA recurrence in this cohort. Additionally, GS 4 + 3 with TP5 was associated with shorter time to recurrence versus GS 4 + 3 alone. Conclusion: Our results emphasize the importance of TP5 and suggest that criteria for tertiary pattern reporting in prostate cancer should be standardized. Further studies are needed to evaluate the role of tertiary patterns in prognostic models.

Objective. We here report a patient with upper urinary tract urothelial carcinoma with hypercalcemia likely due to elevated 1,25-dihydroxyvitamin D. Methods. We present a clinical case and a summary of literature search. Results. A 57-year-old man, recently diagnosed with a left renal mass, for which a core biopsy showed renal cell carcinoma, was admitted for hypercalcemia of 11.0 mg/mL He also had five small right lung nodules with a negative bone scan. Both intact parathyroid hormone and parathyroid hormone-related peptide were appropriately low, and 1,25-dihydroxyvitamin D was elevated at 118 pg/dL. The patient’s calcium was normalized after hydration, and he underwent radical nephrectomy. On the postoperative day 6, a repeat 1,25-dihydroxyvitamin D was 24 pg/mL with a calcium of 8.1 mg/dL. Pathology showed a 6 cm high-grade urothelial carcinoma with divergent differentiation. We identified a total of 27 previously reported cases with hypercalcemia and upper tract urothelial carcinoma in English. No cases have a documented elevated 1,25-dihydroxyvitamin D level. Conclusion. This clinical course suggests that hypercalcemia in this case is from the patient’s tumor, which was likely producing 1,25-dihydroxyvitamin D. Considering the therapeutic implications, hypercalcemia in patients with upper urinary tract urothelial carcinoma should be evaluated with 1,25-dihydroxyvitamin D.

Spatiallydistributed first-principles process models provide anaccurate physical description of chemical processes, but lead to large-scalemodels whose numerical solution can be challenging and computationallyexpensive. Therefore, fast reduced order models are required for model-basedreal-time applications, such as advanced process control and dynamicreal-time optimization. In this paper, we focus on the model reductionof a bubbling fluidized bed (BFB) adsorber, which is a key componentof a postcombustion carbon capture system. From a temporal aspect,dynamic reduced models are generated using the nullspace projectionand eigenvalue analysis method, with the basic idea of quasi-steadystate approximation for the states with fast dynamics. From a spatialaspect, dynamic reduced models are developed using orthogonal collocationand proper orthogonal decomposition to reduce the size of the rigorousmodel. Finally, a computationally efficient and accurate dynamic reducedmodel is developed for the BFB adsorber by combining temporal andspatial model reduction techniques, which is suitable for an onlineoptimization-based control strategy. [ABSTRACT FROM AUTHOR]

PURPOSE:: We describe the current status of quality of care measurement for localized prostate cancer and provide a framework for preserving a leadership role for our specialty in this dynamic and controversial field.MATERIALS AND METHODS:: Basic methodological principles of quality of care assessment were reviewed. Several factors that suggest the potential for current variation in the quality of care for patients with localized prostate cancer, particularly those receiving active treatment, were then analyzed. Subsequently contemporary publications and investigations that comprise the current foundation of prostate cancer quality of care research were reviewed.RESULTS:: The foundation for much of the emerging research in prostate cancer quality of care assessment is based on the Donabedian structure-process-outcome paradigm. The RAND candidate quality indicators for localized prostate cancer were developed in this framework and they represent the first effort to systematically consider the measurement of quality as it relates to prostate cancer. The feasibility of applying the RAND quality indicators to clinical quality of care assessments has been demonstrated, although further modification and refinement of the indicator set are necessary prior to large-scale, population based implementation of these quality assessment measures. Moreover, future quality of care efforts must make the transition to primarily prospective or concurrent quality assessments, such that measures can be taken to modify the structure and/or process of care at the time of delivery or shortly thereafter.CONCLUSIONS:: Prostate cancer quality of care assessment represents a burgeoning domain of urological health services research. To date such initiatives have come from within and outside of our specialty. In the future such efforts are likely to expand and they may have a substantial impact on the clinical and administrative aspects of urological practice. As a result, urologists should maintain a leading role in efforts to further define of quality of care as it relates to prostate cancer and radical prostatectomy. [ABSTRACT FROM AUTHOR]

Introduction Cystic fibrosis (CF) is a systemic autosomal recessive condition characterised by progressive lung disease. CF pulmonary exacerbations (PEx) are episodes of worsening respiratory status, and frequent PEx are a risk factor for accelerated lung function decline, yet many people with CF (PwCF) go untreated at the time of decline. The goal of this quality improvement (QI) initiative was to improve recognition, treatment and follow-up of PEx in PwCF.Methods Using the Model for Improvement, the Cystic Fibrosis Learning Network (CFLN) initiated a QI innovation laboratory (iLab) with a global aim to decrease the rate of lung function decline in PwCF. The iLab standardised definitions for signals of PEx using a threshold for decline in forced expiratory volume in one second (FEV1) and/or changes in symptoms. The FEV1 decline signal was termed FIES (FEV1-indicated exacerbation signal). Processes for screening and recognition of FIES and/or symptom changes, a treatment algorithm and follow-up in the presence of a signal were tested concurrently in multiple settings.Specific aims The specific aim is to increase the per cent of PwCF assessed for a PEx signal at ambulatory encounters and to increase the per cent of recommendations to follow-up within 6 weeks for PwCF experiencing a PEx signal.Results FIES recognition increased from 18.6% to 73.4% across all teams during the iLab, and every team showed an improvement. Of PwCF assessed, 15.8% experienced an FIES event (>10% decline in FEV1 per cent predicted (FEV1pp)). Follow-up within 6 weeks was recommended for an average of 70.5% of those assessed for FIES and had an FEV1pp decline greater than 5%.Conclusion The CFLN iLab successfully defined and implemented a process to recognise and follow-up PEx signals. This process has the potential to be spread to the larger CF community. Further studies are needed to assess the impact of these processes on PwCF outcomes.

Concentrating photovoltaic (CPV) technology has recently gained interest based on its scalability and expected low levelized cost of electricity. The reliability of encapsulation materials used in CPV systems, however, is not well established. For example, the present qualification test for CPV modules includes only real-time ultraviolet (UV) exposure, i.e., methods for accelerated UV testing have not yet been developed. To better define the stress inherent to CPV systems, the UV and infrared spectra transmitted through representative optical systems were evaluated. Measurements of optical components are used to assess expected optical performance and quantify damaging optical exposure. Optical properties (transmittance, refractive index, reflectance, and absorptance) of candidate materials (including PMMA, soda-lime glass, borosilicate glass, and quartz refractors), components (including Ag- and Al-enabled reflectors), and encapsulants (including EVA, ionomer, PDMS, PPMS, polyolefin, and PVB) were identified. The activation spectrum was calculated for the representative optical systems using an assumed action spectrum to compare the expected damaging dose of UV radiation delivered to the cell encapsulation. The dose and flux analysis identifies the significance of IR relative to UV exposure for CPV systems. Because UV light is typically more highly attenuated, the UV dose within the encapsulation may not greatly exceed the unconcentrated global solar condition, but the thermal load scales nearly directly with the geometric concentration. Relative to a previous analysis for crystalline silicon cell technology, the analysis here is performed for III-V multijunction technology. Novel aspects here also include additional materials (such as TPU encapsulation) and additional components (transmission through silicone on glass lenses, antireflective coatings, and the front glass used with reflective systems, as well as reflection off of the cell). [ABSTRACT FROM AUTHOR]