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Growing concerns about the global warming potential of hydrofluorocarbons (HFCs) has led to increasing interest in developing technologies to effectively recover and recycle these refrigerants. Ion...

Recombinant human bone morphogenetic protein 2 (rhBMP-2) plays a pivotal role in complex spine surgery. Despite its limited approval, the off-label use of rhBMP-2 is prevalent, particularly in transforaminal lumbar interbody fusions (TLIFs).To determine the effectiveness and safety of rhBMP-2 use in TLIF procedures versus autograft.Retrospective cohort study.Patients older than 18 years undergoing spine surgery for lumbar degenerative spine disease at a single academic institution.Clinical outcome was determined according to patient records. Radiographic outcome was determined according to plain X-rays and computed tomography (CT).A retrospective study from 1997 to 2014 was conducted on 191 adults undergoing anterior-posterior instrumented spinal fusion with TLIF at a single academic institution. Patient data were gathered from operative notes, follow-up clinic notes, and imaging studies to determine complications and fusion rates. One hundred eighty-seven patients fit the criteria, which included patients with a minimum of one TLIF, and had a minimum 2-year radiographic and clinical follow-up. Patients were further classified into a BMP group (n=83) or non-BMP group (n=104). Three logistic regression models were run using rhBMP-2 exposure as the independent variable. The respective outcome variables were TLIF-related complications (radiculitis, seroma, osteolysis, and ectopic bone), surgical complications, and all complications.Bone morphogenetic protein (n=83) and non-BMP (n=104) groups had similar baseline demographics (sex, diabetes, pre-existing cancer). On average, the BMP and non-BMP groups were similarly aged (51.9 vs. 47.9 years, p.05), but the BMP group had a shorter follow-up time (3.03 vs. 4.06 years; p.001) and fewer smokers (8 vs. 21 patients; p.048). The fusion rate for the BMP and non-BMP groups was 92.7% and 92.3%, respectively. The pseudoarthrosis rate was 7.5% (14 of 187 patients). Radiculitis was observed in seven patients in the BMP group (8.4%) and two patients in the non-BMP group (1.9%). Seroma was observed in two patients in the BMP group (2.4%) and none in the non-BMP group. No deep infections were observed in the BMP group, and in one patient in the non-BMP group (0.96%). Although patients exposed to BMP were at a significantlygreater risk of developing radiculitis and seroma (odds ratio [OR]=4.53, confidence interval [CI]=1.42-14.5), BMP exposure was not a significant predictor of surgical complications (OR=0.32, CI=0.10-1.00) or overall complications (OR=1.11, CI=0.53-2.34). The outcome of TLIF-related complications was too rare and the confidence interval too wide for practical significance of the first model.Evidence supports the hypothesis that off-label use of rhBMP-2 in TLIF procedures is relatively effective for achieving bone fusion at rates similar to patients receiving autograft. Patients exhibited similar complication rates between the two groups, with the BMP group exhibiting slightly higher rates of radiculitis and seroma.

X-ray Phase contract imaging (XPCI) is a promising technique for medical and non-destructive testing[1]. XPCI requires High Aspect Ratio gratings made of high Z materials, e.g. gold. The preferred method of fabrication to realize the very high aspect ratio tall structures is X-ray based lithography, molding, and electroforming process (LIGA) capable of creating high density 1.2 micron features with straight sidewalls that are 120 micron in height [2]. One critical step to pattern such structures is to accurately develop the photoresist mold. This is so because the window is narrow between development and over development. We have proposed and demonstrated the use of a novel electrochemical technique to accurately develop LIGA molds with high repeatability prior to subsequent electroplating. The number and period of development cycles often can be a critical and subjective step where operator error and human judgement can play a significant role drastically affecting the outcome. The analysis must be performed when the sample is still immersed in DI water to avoid capillary action destroying the photoresist molds at high aspect ratios. Some experts have implemented drying techniques to avoid the collapse of high aspect ratio polymer molds when they are dried. Some scientist show a direct phase change from liquid to gas using cyclohexane to mitigate this phenomenon [3]. Sodium chloride (NaCl) salts have been added at ~100 mM to a GG developer LIGA based chemistry. After x-ray exposure of the PMMA the GG developer removes regions where x-ray have severed the PMMA backbone of the polymer mold resulting in a patterned mold that can then be filled with gold to create a high aspect ratio grating. LIGA substrates were prepared using high molecular weight PMMA, x-ray exposed, and actively monitored utilizing electrochemical technique during the development process to search for an endpoint where subsequent gold plating can then occur. As the high aspect ratio mold is developed, the electrochemical interactions are measured between the conducting seed layer and NaCl. We will discuss conductivity of the chemistry, optimizing the process for repeatability, the benefits, and the challenges. Results show an increase in impedance as the exposed PMMA is chemically removed and the conductive NaCl salts get closer to the conductive seed layer at the base of the LIGA PMMA mold. This process uses first of its kind real time electrochemical data capable of detecting more accurately the endpoint of the development process. Previous endpoints were determined by visual inspection, destructive inspection after the fact, large lot burn ins, and single use chemical processes. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525. The views expressed in the article do not necessarily represent the views of the U.S. Department of Energy or the United States Government. Momose, A. and W. Yashiro, X-ray Phase Measurements with Talbot Interferometry and Its Applications. International Conference on Advanced Phase Measurement Methods in Optics an Imaging, 2010. 1236: p. 195-199. Mohr, J., et al., High Aspect Ratio Gratings for X-Ray Phase Contrast Imaging. International Workshop on X-Ray and Neutron Phase Imaging with Gratings, 2012. 1466: p. 41-50. Koch, F., et al., Increasing the aperture of x-ray mosaic lenses by freeze drying. Journal of Micromechanics and Microengineering, 2015. 25(7).

X-ray phase contrast imaging (XPCI) allows for medical and non-destructive testing of soft tissue [1]. High aspect ratio (HAR) gratings (100:1) are difficult to achieve and are a key element of XPCI gold gratings PMMA lithography, molding, and electroforming (LIGA) process [2]. Development of uniform, continuous HAR gold gratings over a large area is difficult as they easily tilt and delaminate. One technique for stabilizing the mold during development is to incorporate relief structures into mold, providing more surface area at the bottom, which results in segmented gratings [2]. In the current work, honeycomb supports are used to stabilize the PMMA mold during development and plating to realize continuous gratings centimeters in lateral length. Our goal is to fabricate micron size HAR gratings ~10 cm in lateral length that are ideal for XPCI applications enabling larger field of view for the XPCI imaging. Honeycomb structures were patterned on a 100 mm substrate. A sheet of PMMA is then bonded and fly cut to desired height. An x-ray exposure then patterns the PMMA mold prior to the fabrication of the top honeycomb structure. The gratings are then developed and electroplated having structural support on both sides. The use of bottom and top honeycomb arrays provide unique mechanical support to the fragile PMMA mold during development and electroplating of the HAR grating. Momose, A. and W. Yashiro, X-ray Phase Measurements with Talbot Interferometry and Its Applications. International Conference on Advanced Phase Measurement Methods in Optics an Imaging, 2010. 1236: p. 195-199. Mohr, J., et al., High Aspect Ratio Gratings for X-Ray Phase Contrast Imaging. International Workshop on X-Ray and Neutron Phase Imaging with Gratings, 2012. 1466: p. 41-50. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525. The views expressed in the article do not necessarily represent the views of the U.S. Department of Energy or the United States Government. Figure 1: Schematic of mold stabilization design (left), honeycomb pattern (right) Figure 1

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We present an advanced system for on-line position-specific carbon isotope analysis. The main limitation of on-line intramolecular isotope ratio measurements has been that optimal pyrolytic fragments are obtained mostly at temperatures where the analyte has not completely reacted. As a result of undetermined isotopic fractionation, the isotopic signatures of the pyrolysis products are not strictly equal to these of the equivalent moieties in the parent molecule. We designed a pyrolytic unit in which both temperature and reaction time are variable parameters, enabling determination of the enrichment factor of the pyrolysis at optimal temperature by construction of a Rayleigh plot. In the case of methyl tert-butyl ether (MTBE) presented here, a 'pre-pyrolysis' fractionation of MTBE leading to a depletion of 0.9 parts per thousand was discovered and the enrichment factor of the optimal pyrolysis reaction was determined at -1.7 parts per thousand. Absolute delta C-13 values of two functional groups of MTBE - the methoxy group and the 2-methylpropane group - could be determined with 95% confidence intervals of 0.4 parts per thousand and 0.5 parts per thousand, respectively.

A study was implemented to investigate the presence of contagious caprine pleuropneumonia (CCPP) in East Turkey. This study was based on clinical surveillance in the field, surveillance at regional slaughterhouses and regular submission of suspected lesions to regional laboratories. The results showed that the agent of CCPP, Mycoplasma capricolum subspecies capripneumoniae (Mccp), could be detected by culture and specific polymerase chain reaction from 37.5% (12/32) of lung samples taken from goats of ten different herds. This agent was also isolated from two of 13 sheep samples (one from the lung and the other from a nasal swab). Mycoplasma capricolum subsp. capripneumoniae was isolated in pure culture and characterised at a finer molecular level. The East Turkish isolate was found to be closely related to another strain of Turkish origin, as well as to Mccp strains isolated in Tunisia. The isolation of Mccp from sheep lung lesions brings the strict host-specificity of this pathogen into question. It may also indicate that Mccp presents a risk for wildlife in the region. Such results, the authors believe, demonstrate that adequate risk assessments should be undertaken in Turkey and neighbouring countries.