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Around the time Maurice Hasler was building a spectrograph for use in his then-new Applied Research Laboratories in California, and about a year before Walter Baird started his namesake company just outside of Boston, Richard F. Jarrell was finishing up his four-year degree in Physics at the Massachusetts Institute of Technology. His father, J. O. Jarrell (who disliked and seldom used his given name, Joshua Oscar), had an established business in Boston selling microscopes and other optical goods. The elder Jarrell was taking on a new product line: spectrographs and other analytical instruments from London-based Adam Hilger Limited. He arranged for Dick, his oldest son, to spend the summer at Hilger learning firsthand as much as possible about their instrumentation. That trip, followed by a graduate fellowship project at MIT, set the stage for Jarrell's life in science and business-and for a spectroscopy company that still carries his name.

The computer program called Solar_PVHFC has been modified to model a compound parabolic concentrator (CPC) that uses photovoltaic cells to produce electrical energy. This program was used to study the effects of concentration ratio, truncation height ratio, and photovoltaic cell efficiency on electrical power output and relative levelized cost of energy (LCE) of a fixed CPC photovoltaic device. Comparisons are made to fixed, conventional flat photovoltaic panels. This study indicates that CPCs can reduce the levelized cost of electrical energy produced by high efficiency, high cost photovoltaic cells, but provides no advantages for lower efficiency, lower price photovoltaic cells.

Percutaneous nephrolithotomy (PCNL) is considered the standard for large renal stones.Previous evaluations have found that gaining initial access to the collecting system represents the most difficult portion of PCNL procedures. We sought to broadly assess the experience of urology residents in the United States (USA) and evaluate for factors associated with increased comfort in percutaneous access.METHODS: Program representatives from each the 137 Accreditation Council for Graduate Medical Education (ACGME) certified resident programs in the USA were contacted and asked to distribute our survey to their current residents and recent graduates. Residents were queried about their PCNL volume, program factors, and comfort level with percutaneous access. Survey responses were summarized using descriptive statistics. Exploratory differences in fluoroscopic (FL) and ultrasound guided (US) access comfort based on training, experience characteristics were performed using chi-square or Fisher's exact tests. P-values were adjusted to control the false discovery rate (FDR) at 5%.RESULTS: There were 79 responses from residents in 20 states. 77% reported working with an Endourology-trained faculty member, and 37% had an Endourology fellowship program at their institution. 63% stated that they trained at a program where urologists sometimes obtain access with 56% of those stating that urologists primarily obtained access. Residents were almost four times as likely to state they had attempted FL as opposed to US access. 63% reported they felt their residency program would prepare them to achieve FL access and 11% reported the same for US access. 87% reported plans to perform PCNL in practice but only 11% planned to achieve their own access by any means. Training at a program where access in primarily obtained by urologists was associated with an increased likelihood of being comfortable with FL access (p ¼ 0.006), as was being in the upper quartile of operative volume (p ¼ 0.034), and working with an Endourology-trained faculty member (p ¼ 0.055). Training at an institution with an Endourology fellowship was also associated with being more comfortable with ultrasound access (p ¼ 0.012).CONCLUSIONS: Despite the majority of residents reporting that they had adequate training in obtaining access, a small minority plan to perform their own access. Furthermore, comfort in ultrasound guided access remains low among our respondents in the United States. Further research should be undertaken to assess and improve the translation of training experience into post-residency practice patterns.

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