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Photovoltaic/Thermal hybrid (PVT) systems have shown promise as a viable commercial and private source of renewable energy. The purpose of this meta study is to combine contemporary research findings in the area of Photovoltaic (PV) and Photovoltaic/Thermal Hybrid solar systems and attempt to offer general optimisation principles for future PVT devices. Design parameters with which we attempt to optimise through will include PV material choice, CPC inclusion and system temperature optimisation for operational lifetime gain and power yield. It was found that we can combine CPC, closed glass design, spiral web flow and m>0.003kg/s to optimise the c-SI based systems and obtain an overall PVT efficiency gain of 5.5±1.6%, and that mass flow rates exceeding 0.003 kg/s can increase longevity by 80% on average and increase electrical efficiency by 1.2% when compared to conservative lower mass flow rates. Hydrogenated amorphous silicon systems were also deemed to create less high-quality energy and overshooting required thermal needs when using personal/private power statistics as selection criteria.

Main text Cosmetics and personal care products are widely used globally. Although toxic elements are banned as intentional ingredients, they may exist as impurities either as contaminants in the raw ingredients, or as by-products of the manufacturing process. These toxic elements can accumulate in the body over time and cause adverse health effects. Different regions around the world have established relevant guidelines and regulations to safeguard the safety of consumers. Therefore, there is a need for metrology institutes to strengthen their measurement capabilities in this area. The supplementary comparison APMP.QM-S17: Elements in Lipstick Material was coordinated by the Health Sciences Authority, Singapore. Four measurands (arsenic, cadmium, mercury and lead) with maximum limits stated under the Association of Southeast Asian Nations (ASEAN) Guidelines on Limits of Contaminants for Cosmetics were chosen. Only one key comparison in the area of cosmetics (CCQM-K106: Lead, Arsenic and Mercury in Cosmetic Cream) was organised by the National Institute of Metrology (NIM) China in 2013. Hence, it was timely to organise another comparison in this area that covered cosmetics but in a different matrix. The study sample (lipstick) offered different analytical challenges as compared to the cream material used in the previous comparison. Moreover, it enabled National Metrology Institutes/Designated Institutes (NMIs/DIs) that did not participate in CCQM-K106 to demonstrate their measurement competencies. Seven institutes participated in the comparison for arsenic, nine for cadmium and lead, and eight for mercury. All participating NMIs/DIs employed microwave-assisted acid digestion for sample dissolution. Inductively coupled plasma mass spectrometry (ICP-MS) and sector field ICP-MS (SF-ICP-MS) were the two most commonly used instrumental techniques. Results of all participating NMIs/DIs were evaluated against the supplementary comparison reference value (SCRV). The SCRV and associated uncertainty were determined from results of NMIs/DIs that participated in the supplementary comparison using methods with demonstrated metrological traceability. For cadmium, mercury and lead, the median was used as estimator of the SCRVs. For arsenic, the arithmetic mean was used as estimator of the SCRV. The SCRVs (± expanded uncertainty) for arsenic, cadmium, mercury and lead (in mg/kg) were 4.188 (± 0.237), 2.0670 (± 0.0171), 2.732 (± 0.147) and 10.406 (± 0.080), respectively. The degree of equivalence and its associated uncertainty were calculated for each submitted result. Most participating institutes were able to demonstrate their capabilities in the determination of elements in lipstick material. Participating NMIs/DIs that have successfully participated in APMP.QM-S17 have demonstrated measurement capabilities in determining mass fraction of transition elements and metalloids/semi-metals, in mass fraction range from 0.1 mg/kg to 25 mg/kg in cosmetic matrices with high organic contents, such as lipstick. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Previous studies suggested that patients with pure struvite calculi rarely have underlying metabolic abnormalities. Therefore, most of these patients do not undergo metabolic studies. We report our experience with these patients and their response to directed medical therapy. Between 1/2005 and 9/2012, 75 patients treated with percutaneous nephrolithotomy for struvite stones were identified. Of these, 7 had pure struvite stones (Group 1), 32 had mixed struvite stones (Group 2), both with metabolic evaluation, and 17 had pure struvite stones without metabolic evaluation (Group 3). The frequency of metabolic abnormalities and stone activity (defined as stone growth or stone-related events) was compared between groups. The median age was 55 years and 64 % were female. No significant difference in race, infection history, family history, stone location or volume existed between groups. Metabolic abnormalities were found in 57 % of Group 1 and 81 % of Group 2 patients. A similar proportion of Group 1 and 2 patients received modification to or continuation of metabolic therapy, whereas no Group 3 patients received any directed therapy. In patients with >6 months follow-up, the stone activity rate between Groups 1 and 2 appeared similar whereas Group 3 trended towards higher stone activity rate. Metabolic abnormalities in pure struvite stone formers appear to be more common than previously reported. Directed medical therapy in these patients may reduce stone activity. The role of metabolic evaluation and directed medical therapy needs reconsideration in patients with pure struvite stones.

328 Background: Liver transplant (LT) remains the best curative standard for HCC within Milan criteria (Milan). Nonsurgical locoregional treatments, including TACE and ablation, offer a bridge to surgical management and attempt to downstage or maintain patients (pts) within Milan pending liver transplant and donor organ availability. We investigated clinical factors that predict successful downstaging of HCC and liver transplant. Methods: In this single-institutional retrospective analysis, pts with early-intermediate stage HCC within Milan (control) vs beyond Milan were evaluated for clinical outcome. Clinical factors including treatment and response, demographics, TACE distribution (number of treatments, timing, and response), and status of liver transplantation (timing and if received) were correlated to overall survival (OS). OS was calculated using the Kaplan-Meier method. Results: HCC pts (n = 343) considered for LT or downstage to LT were included in the study: 75% male, 13% African American, 55% Caucasian, and 14% Asian. 12% of pts had HBV, 53% had HCV, 2% had both HBV and HCV. 221 pts were diagnosed within Milan vs 122 beyond Milan, in which 36% (n = 44) were still within UCSF criteria (UCSF). 43% of those diagnosed within Milan ultimately received LT vs 16% of those diagnosed beyond Milan. 49% of pts (n = 60) initially beyond Milan were downstaged to within Milan, via TACE, wherein 27% received LT; this group accounted for 13% all LT. However, in the subset of pts beyond Milan but within UCSF, 68% were downstaged to within Milan, wherein 40% received LT. In pts initially within Milan, 21% (n = 47) progressed beyond Milan, but 40% of this subset was downstaged back to within Milan. Pts both within and beyond Milan had a median of 2 TACE procedures. Differences in the rates of LT relative to the number of TACE were significant (p = 0.022) for pts initially within Milan; for < / = 2 TACE, 54% had LT; for > 2 TACE, 26% had LT. Similar comparison was nonsignificant for pts initially beyond Milan (p = 0.95); rates of LT for < / = 2 TACE and > 2 TACE were 17% and 16% respectively. Median OS for non-LT recipients was 5 years vs not reached for LT recipients ( > 70% alive at 8 years, p < 0.001). Pts initially beyond Milan but within UCSF criteria had similar OS vs those initially within Milan (both 75% at 4 years), but OS was worse (50% at 4 years) for those beyond UCSF (p = 0.024). Conclusions: Liver transplantation significantly increased OS in early-intermediate stage HCC. Increased number of TACE procedures was associated with decreased likelihood of ultimate LT in pts initially diagnosed within Milan, particularly when they had > 2 TACE. Pts initially beyond Milan but within UCSF criteria had similar OS vs those initially within Milan; this former subset had a good chance of being downstaged to Milan and ultimately receive LT. Additional clinical factors that predict successful downstaging of HCC and LT are being investigated.