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35th European Photovoltaic Solar Energy Conference and Exhibition; 2098-2103, The main objective of this study is to compare and analyze different PV system performances in Bolivia, Chile and Germany with different climate preconditions like solar irradiation and ambient temperature. The analyzed PV systems in Chile allow a comparison of poly-crystallin silicon- (p-Si), mono-crystallin silicon- (m-Si) and copper indium gallium selenide- (CIGS) solar cell technologies. Furthermore, there are four PVstrings with different inverter configurations to compare the performance of high to low power inverters and undersized to oversized inverters. The analysis of the evaluated PV systems includes monthly average daily final yield, capacity factor, performance ratio and ratio of self-sufficiency. The highest performance ratio was determined with a combination of oversized inverter and CIGS-cells with 89 % for the overall operation time. Average overall PV system performance ratios in Bolivia, Chile and Germany for the analyzed time-periods in 2015 and 2017 in Bolivia, Chile and Germany were determined with 83 %, 87 % and 69 %, respectively. Overall, the optimal operation conditions result a in energy balance solar coverage ratio of 1.16 in Bolivia and 0.53 in Chile. The climate preconditions of the different countries are one of the key factors for the performance of a PV system, as shown in the results of this paper.

OBJECTIVES: The objective of the study described in this and an accompanying series of papers was to develop a laboratory generated exposure atmosphere to be used for chronic inhalation toxicity studies in rats that resembles, as closely as possible, personal exposures seen by workers during road paving operations. METHODS: To achieve this objective, atmospheric workplace samples were collected at road paving worksites and compared analytically with bitumen fume samples collected from the headspace of hot bitumen storage tanks. In Preiss et al. (2006) the collection and analysis of workplaces samples is described. This contribution describes the strategy for the in-line extraction of a suitable fraction of bitumen fume collected from the headspace of a bitumen storage tank and the comparison of the collected condensate to workplace samples. RESULTS: Results show that is possible to develop a collecting procedure that allows sampling from hot bitumen storage tanks in an operational asphalt mixing plant. The sampling procedure has been optimized to collect material that matches the workplace samples as closely as possible. The comparison to workplace samples has been performed using parameters that can be analyzed in both the workplace samples and the bitumen fume condensate collected from the tanks. Boiling point distribution (BPD), UV fluorescence (UV-Fl) and content of individual polycyclic aromatic hydrocarbons (PAH) were selected as parameters. The BPD of the final collected bitumen fume condensate did not differ by more than 17 degrees C from any point on the average BPD curve of the workplace samples, in the range from 5 to 95%. UV-Fl of the bitumen fume condensate nearly exactly matched the average UV-Fl of the workplace samples. However, the sum of the 17 PAHs analyzed in the test samples, compared to the mass of the condensate, is lower by a factor of approximately 3 than the sum of the 17 PAHs in some personal samples compared to the mass of Total Organic Matter (TOM). It has to be recognised that during the collection of the workplace samples, despite all efforts a number of the workers who carried a personal sampler could not be prevented from smoking.

OBJECTIVES: Undertaking a chronic inhalation study on bitumen fume presents a challenge in terms of generating large amounts of representative fume. The objective of the study described in this and the following contributions was to collect sufficient fume and develop a laboratory-generated exposure atmosphere that resembles, as closely as possible, personal exposures seen in workers during road paving operations, for use in chronic inhalation toxicity studies in rats. METHODS: To achieve this goal, atmospheric workplace samples were collected at road paving work sites both by Shell Global Solutions, Int. (Shell) and by the 'Berufsgenossenschaftliches Institut fur Arbeitssicherheit' (BIA, Germany) and compared with bitumen fume condensate samples collected from the head space of hot bitumen storage tanks. Part 1 describes the collection and analysis of personal and static workplace samples. Different sampling methods were also used to allow a comparison of the standard German sampling method with the most common industry method used. Samples were analyzed by Shell, BIA and by the Fraunhofer Institute of Toxicology and Experimental Medicine (Fh-ITEM, Germany) using different methods. Parameters determined were: total particulate matter (TPM), benzene soluble matter (BSM), semi-volatiles (SV), total organic matter (TOM), boiling point distribution (BPD), polycyclic aromatic hydrocarbons (PAHs) and UV fluorescence (UVF). RESULTS: The BPD of personal and static samples had almost identical start and end points, but static samples show a tendency towards an increase in amounts of higher boiling point compounds. Personal samples generally show higher PAH concentrations than comparable static samples. The results of the analysis of personal workplace samples were used to establish validation/acceptance criteria for the bitumen fume condensate sampled from storage tanks for the inhalation study, which is described in a further publication. CONCLUSIONS: The criteria involve a range of parameters that can be analyzed in both workplace samples and samples of tank fume condensate: BPD, UVF and content of individual PAHs were selected as parameters.

Undertaking a chronic inhalation study on bitumen fume presents a challenge in terms of generating sufficient amounts of representative fume. The objective of the study described in this and in previous publications was to collect sufficient fume and use this to develop a laboratory-generated exposure atmosphere, for use in chronic inhalation toxicity studies in rats that resembles, as closely as possible, personal exposures seen in workers during road paving operation. To achieve this goal, atmospheric workplace samples were collected at road paving work sites and compared with bitumen fume condensate samples collected from the headspace of hot bitumen storage tanks. In Parts 1 and 2, we described the collection and analysis of workplace samples, the strategy for in-line extraction of a suitable fraction of bitumen fume collected from the headspace of a bitumen storage tank and the comparison of the collected condensate to the workplace samples. This paper (part 3) describes the regeneration of bitumen fume for inhalation and the exposure setup used for inhalation studies.

The neurosecretory cells of the insect brain were described many years ago and we know that their secretions are stored in the corpora cardiaca. Neurosecretion is not, however, limited to the cephalic region. Various ganglia of the ventral nerve cord also possess neurosecretory elements controlling various functions. Associated with these ganglia are neurohaemal organs which present a structural resemblance to the corpora cardiaca and appear to be neurosecretory storage and release centres.

Over the past 10 years, many laboratories have investigated lipid metabolism and atherogenesis with a variety of transgenic and gene knockout mouse models. Although many of these studies have yielded valuable insights, some have been hampered by a paucity of useful antibodies against mouse proteins. For example, many laboratories have analyzed genetic and dietary interventions affecting lipoprotein metabolism without useful antibodies against mouse apolipoprotein (apo) B. In this study, we sought to develop highly specific monoclonal antibodies against mouse apoB-100. To achieve this goal, gene-targeted mice that synthesize exclusively apoB-48 (apoB-48-only mice) were immunized with mouse apoB-100. The immune response against apoB-100 was robust, as judged by high titers of antibodies against mouse apoB-100. After fusing the splenic lymphocytes of the apoB-48-only mice with a myeloma cell line, we identified and cloned hybridomas that produced mouse apoB-100-specific monoclonal antibodies. Those antibodies were useful for developing sensitive and specific immunoassays for mouse apoB-100. This study illustrates the feasibility and utility of using gene-targeted mice to develop monoclonal antibodies against mouse proteins.

Several human diseases are characterized by defects in the synthesis and secretion of the apolipoprotein (apo) B-containing lipoproteins. Familial hypobetalipoproteinemia is caused by mutations in the apo-B gene and is characterized by abnormally low plasma concentrations of apo-B and low-density lipoprotein (LDL) cholesterol. Another apo-B deficiency syndrome, abetalipoproteinemia, is caused by mutations in the gene for microsomal triglyceride transfer protein (MTP). MTP is a microsomal protein that is thought to transfer lipids to the apo-B protein as it is translated, allowing it to attain the proper conformation for lipoprotein assembly. A third apo-B deficiency syndrome, Anderson's disease (or chylomicron retention disease), is characterized by the inability to secrete apo-B-containing chylomicrons from the intestine but an apparently normal capacity to secrete lipoproteins from the liver. To more fully understand these human apo-B deficiency syndromes, our laboratory has generated and characterized gene-targeted mouse models. This review summarizes what has been learned from these animal models.