For telluride compounds, the presence of electrically active contaminants in the grown crystals is one of the critical factors that can severely limit the ensuing device performance. In order to minimize contamination from both precursor material handling and environmental sources during the compounding operation, a fully integrated traveling heater method (THM) CdTe synthesis process was developed. Based on glow discharge mass spectroscopy (GDMS) analysis, the average total impurity content, excluding carbon, nitrogen, and oxygen, is in the order of 100 PPB atomic, with zinc being the major contaminant and accounting for more than 40 pct of this value.

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Objective To compare the mortality rates of patients with claudication and de novo femoropopliteal lesions treated with and without paclitaxel coated devices (PCD). Background A recent meta-analysis, mostly including patients with claudication and de novo femoropopliteal lesions but also with recurrent stenoses and critical limb ischemia, has shown a significant excess mortality in patients treated with PCD. Methods Comparison of two historical cohorts of patients presenting with claudication and de novo femoropopliteal lesions treated with and without PCD between 2008 and 2018. Results After review of 5219 arteriograms in patients presenting with peripheral artery disease, 700 consecutive patients were included consisting in 72.6% of male (n = 508). Mean age was 68.1 ± 8.5 years. 45.7% of the patients (n = 320) had a treatment including a PCD. Mean femoropopliteal lesion length was 123 ± 91 mm including 44.6% of occlusions. Patients of the control group were censored at crossover to paclitaxel when applicable. Mortality rates at 1, 2 and 5 years were 4.6%, 7.5%, 19.4% and 1.6%, 6.2%, 16.6% in the non-PCD and PCD groups respectively. The relative risks of death when using PCD were 0.35 (p = 0.03), 0.83 (p = NS) and 0.86 (p = NS) at 1, 2 and 5 years respectively. Conclusion There was no excess mortality in patients with claudication and de novo femoropopliteal lesions treated with paclitaxel coated devices at 1, 2 and 5 years of follow-up in this cohort. The current study suggests that additional prospective randomized studies properly powered to study mortality are necessary.

Objective: To compare the mortality rates of patients with claudication and de novo femoropopliteal lesions treated with and without paclitaxel coated devices (PCD).Background: A recent meta-analysis, mostly including patients with claudication and de novo femoropopliteal lesions but also with recurrent stenoses and critical limb ischemia, has shown a significant excess mortality in patients treated with PCD.Methods: Comparison of two historical cohorts of patients presenting with claudication and de novo femoropopliteal lesions treated with and without PCD at our institution between 2008 and 2018.Results: After review of 5219 arteriograms in patients presenting with peripheral artery disease, 700 consecutive patients were included consisting in 72.6% of male (n=508). Mean age was 68.1±8.5 years. 45.7% of the patients (n=320) had a treatment including a PCD. Mean femoropopliteal lesion length was 123±91mm including 44.6% of occlusions. Patients of the control group were censored at crossover to paclitaxel when applicable. Mortality rates at 1, 2 and 5 years were 4.6%, 7.5%, 19.4% and 1.6%, 6.2%, 16.6% in the non-PCD and PCD groups respectively. The relative risks of death when using PCD were 0.35 (p=0.03), 0.83 (p= NS) and 0.86 (p= NS) at 1, 2 and 5 years respectively. Conclusion: There was no excess mortality in patients with claudication and de novo femoropopliteal lesions treated with paclitaxel coated devices at 1, 2 and 5 years of follow-up. The current study suggests that additional prospective randomized studies properly powered to study mortality are necessary.

Background: The Trans-Atlantic Inter-Society Consensus Document (TASC II) aims to comprehensively describe the case scenarios of aortoiliac and femoropopliteal lesions to suggest an endovascular or a surgical approach. Over time, it has become a guide for describing the gravity of arterial lesions. Purpose: To assess the revised TASC II system for classifying arterial lesions in a large database of patients presenting with claudication. Materials and Methods: This study was a retrospective review of the arteriograms of patients with intermittent claudication. Aortoiliac and femoropopliteal lesions were classified according to the TASC II. When no consensus was reached, the lesion was rated as unTASCable. Results: In total, 1454 patients were included (male: 62.1%, 66.8±9.3 years). There were 39% aortoiliac lesions (n=960/2462) and 61% femoropopliteal lesions (n=1502/2462); 33.6% of the patients (n=489/1454) were associated with aortoiliac and femoropopliteal lesions. In addition, 20% of the lesions (n=493/2462) were unTASCable, and 26.7% of the patients (n=388/1454) had at least 1 unTASCable lesion. There were 4 categories of unTASCable lesions: (1) association with a common femoral artery lesion in 53.1% (n=262/493); (2) iliac artery lesions in 23.1% (n=114/493); (3) femoropopliteal lesions whose lengths did not fit into any category in 16.6% (n=82/493); and (4) association with an aortic lesion in 7.1% (n=35/493). The interobserver agreement was 0.97 for anatomically describing the infrarenal arterial tree and 0.85 for TASCing, with the lesions lowering to 0.69 for aortoiliac lesions. Conclusion: Using the revised TASC II case scenario, 26.7% of the patients had at least 1 unTASCable lesion. Reporting peripheral artery disease using a comprehensive anatomical description of the infrarenal arterial tree showed better interobserver reproducibility.

The specific health hazards associated with exposure to asbestos are defined in terms of definitions of the asbestiform minerals—definitions that distinguish between acicular fragments and true fibers and that relate to the respirability of airborne particulates. The respiratory hazards include asbestosis, mesothelioma, and cancer. Estimates of cancer incidence—ranging from those of Joseph Califano, U.S. Secretary of Health, Education, and Welfare, to those of Doll and Peto—are evaluated critically. Bronchogenic cancer incidence is reviewed and discussed. The role of synergism with cigarette smoking in disease is discussed. The incidence of mesothelioma in relation to human epidemiology, the numerous other substances that cause mesothelioma in animals, the inactivity of anthophyllite asbestos, an epidemic in Turkey, and experience in the mines of Quebec Province, Canada, are examined. Cancers of the gastrointestinal tract associated with the ingestion of asbestos from drinking water or from lung clearance mechanisms are examined critically. The dearth of reliable human epidemiology and extensive animal studies are considered. Dose-response relationships associated with asbestosis are presented, and the threshold exposure limit determined for chrysotile miners is mentioned. One cohort of some 250 men occupationally exposed to moderately controlled airborne chrysotile concentrations for 25 years is evaluated. Dose-response relationships associated with cancer are discussed. The single-fiber hypothesis is criticized. Background incidence of asbestosis in persons without occupational exposure is discussed, and intrinsic lung defense mechanisms are touched upon. Hazardous exposure conditions for asbestos are defined. The epidemiology of the asbestos miners of Quebec Province is summarized, and recent experience is considered. The British criterion of acceptable risk, based on a 1% probability of developing the earliest clinical signs of asbestos-related disease, is discussed in light of society's willingness to accept reasonable risks and in light of the impracticality of zero risk. The effects of short intense exposure and their overwhelming effects on lung clearance mechanisms are discussed. The geographic distribution of asbestos-bearing geological formations is mentioned and hazards associated therewith are touched on. The hazardous entities, that is, those airborne particulates associated with asbestosis, are defined in terms of their dimensions in relation to respirability, deposition in the lungs, lung clearance mechanisms, tissue cell dimensions, and cytotoxicity. The origin of the 3:1 aspect ratio for fiber definition is delved into. Some animal studies on the effects of fiber dimensions are mentioned. The dimensions of the hazardous entities involved in cancer are presented. The dimensions of asbestos found as living tissue burden in humans are compared with the size distribution of airborne atmospheric particulates. Based upon all the foregoing considerations, definitions are developed of airborne fibrous particulates to be considered for monitoring purposes. The various definitions of asbestiform particles are mentioned. The respective limitations of electronic and optical microscopy are discussed. Definitions leading to efficient, reproducible hazard assessment are proposed. Finally, acceptable, realistic occupational exposures to asbestos are proposed, and demands for zero exposure are set against the perspective of the total quality of life.

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