Experimental assessment of pollutant emissions from residential fuel cells and comparative benchmark analysis.

Energy transition currently brings focus on fuel cell micro-combined heat and power (mCHP) systems for residential uses. The two main technologies already commercialized are the Proton Exchange Membrane Fuel Cells (PEMFCs) and Solid Oxide Fuel Cells (SOFCs). The pollutant emissions of one system of each technology have been tested with a portable probe both in laboratory and field-test configurations. In this paper, the nitrogen oxides (NOx), sulphur dioxide (SO2), and carbon monoxide (CO) emission levels are compared to other combustion technologies such as a recent Euro 6 diesel automotive vehicle, a classical gas condensing boiler, and a gas absorption heat pump. At last, a method of converting the concentration of pollutants (in ppm) measured by the sensors into pollutant intensity per unit of energy (in mg/kWh) is documented and reported. This allows for comparing the pollutant emissions levels with relevant literature, especially other studies conducted with other measuring sensors. Both tested residential fuel cell technologies fed by natural gas can be considered clean regarding SO2 and NOx emissions. The CO emissions can be considered quite low for the tested SOFC and even nil for the tested PEMFC. The biggest issue of natural gas fuel cell technologies still lies in the carbon dioxide (CO2) emissions associated with the fossil fuel they consume. The gas absorption heat pump however shows worse NOx and CO levels than the classical gas condensing boiler. At last, this study illustrates that the high level of hybridization between a fuel cell and a gas boiler may be responsible for unexpected ON/OFF cycling behaviours and therefore prevent both sub-systems from operating as optimally and reliably as they would have as standalone units.

Primary and secondary amputation in critical limb ischemia patients: different aspects.

The TASC II working group reports on primary amputation incidence rates vary between 12 and 50 per 100,000 per year. The primary amputation rate does not only depend on co-morbidities like diabetes and PAD, but also on local factors like the regional availability of vascular surgeons and interventional radiologists and their case load. Further-more, several studies could show that increasing revascularisation rates have drastically reduced amputation rates in the US, with a 50% decrease in amputation rates during a 10 year study period and a corresponding increase in surgical and endovascular revascularisation rates. An analysis of national and state US databases confirmed a drop in major amputations and open surgical revascularisations, in favour of an increase in endovascular interventions. The same study observed an increase in minor amputations during the same period. However, it remains unclear whether this trend is a consequence of the increased usage of endovascular procedures in high-risk patients who are unfit for open surgery or of earlier endovascular intervention in less critical lesions. This review gives an overview of the incidence, indication, amputation-level finding and outcome of major amputations performed in critical limb ischemia (CLI) patients.

[Male depression in a population sample of young males. Risk and symptom profiles]. / "Male depression" in einer Bevölkerungsstichprobe junger Männer. Risiko und Symptome.

The concept of male depression basically assumes that the well-known depressive symptoms in males are compensated for or masked by external behavioral patterns, which are atypical for depression and therefore not included in conventional depression inventories. In a community sample of young males (n=1,004) the general well-being and risk of male depression were investigated using the WHO-5 Well-Being Scale and the Gotland Scale for Male Depression. The main questions focused on the analysis of symptoms dependent on the risk of male depression. Hypotheses were related to depressive symptoms being masked by distress symptoms, to the dimensionality of the Gotland Scale, to different symptom clusters and to the contribution of isolated symptoms to the risk of depression. The results demonstrated a reduced well-being and a risk of male depression in 22% of the respondents. The data gave no evidence to support the hypothesis that depressive symptoms are masked by distress symptoms or for latent depression and stress components. However, a "depression cluster" and a "distress cluster" could be differentiated by cluster analyses giving indications of the clinical relevance of the male distress symptoms for the development of depression. The more severe these are, the higher is the risk of male depression. Finally, the results are discussed in the face of the limitations of the study, the previous evidence and open questions.

Subjective well-being and 'male depression' in male adolescents.

BACKGROUND: The concept of male depression is based on the hypothesis that typical symptoms of depression in men often seem to be masked by non-typical male distress symptoms not considered in common depression inventories. Although there is a large amount of clinical evidence, scientific evidence is still lacking. The study aims at further validating the concept of male depression, by obtaining information on symptoms reported by males, and analyzing the dimensional structure of the Gotland Scale of Male Depression [Rutz, W., 1999. Improvement of care for people suffering from depression: The need for comprehensive education. International Clinical Psychopharmacology 14, 27-33.]. METHODS: A community sample of male adolescents aged 18 (n=1004) was asked to complete the WHO-5 Well-being Index [Bech, P., 1998. Quality of life in the psychiatric patient. London: Mosby-Wolfe.] and the Gotland Scale of Male Depression [Rutz, W., 1999. Improvement of care for people suffering from depression: The need for comprehensive education. International Clinical Psychopharmacology 14, 27-33.]. Principal component analysis with promax rotation was calculated to analyze the dimensional structure of the Gotland Scale. Cluster center analyses were used to classify the sample according to the symptoms' characteristics. RESULTS: General well-being was rather reduced, and 22% of the respondents were seen to be at risk of male depression. There was no evidence for the hypothesis that young males tend to mask their depressive symptoms with distress symptoms. Depressive and male distress symptoms appeared to be mixed in a dominant factor, while male distress symptoms constitute an additional minor factor. A cluster of 38% of those at risk for depression could be identified who reported significantly elevated male distress symptoms. Irritability turned out to be the single item of the Gotland Scale with the highest item-total correlation. LIMITATIONS: Risk of depression was not assessed by an additional depression scale or evaluated by a clinical rating. CONCLUSIONS: Male distress symptoms should be considered when diagnosing depression in men. Further research is needed with respect to comorbidity and differential diagnoses, which should also include bipolar depression.

Measurements of claw dimensions in cows before and after functional trimming: a post-mortem study.

The aim of this study was to compare measurements of the medial and lateral claws of the hind feet in cattle, and to establish reference values to aid in functional claw trimming. Variables of the medial and lateral claws of 40 hind feet obtained from 40 slaughtered German Simmental cows were measured. To standardise the observations the soles of both the medial and lateral claws were first trimmed to a defined thickness of 5mm at the apex and 8mm at the heel, before measurements were taken. After this standardisation, the mean lengths of the dorsal walls of the two claws were not significantly different (means, lateral 76.8, medial 77.1 mm). However, there were considerable other differences. For example, the soles of the lateral claws were significantly (P < 0.01) longer (means, 120.1mm versus 112.7 mm, and wider (means, 52.0 mm versus 42.5 mm). In 36/40 feet, the sole of the lateral claw protruded approximately 2-3mm above the sole of the medial claw after the standardisation. The soles of the lateral claws were therefore then trimmed to the height of the medial claw ("levelling") and the measurements were repeated in the lateral claws. The dorsal wall of the lateral claw was then significantly shorter than that of the medial claw (means, 74.8 mm versus 77.1 mm) and, most importantly from a functional point of view, the sole was significantly thinner than that of the medial claw (means, 2.71 mm versus 5mm at the toe tip, 4.9mm versus 8 mm at the heel). Finally, the horn capsule of all claws was removed and various measurements of the corium surface were made. The length of the dorsal corium surface did not differ statistically (P > 0.05) between the lateral (mean, 62.6 mm) and medial (mean, 62.5 mm) claws. Strict adherence to the principles of functional trimming thus reduces the thickness of the sole, the length of the dorsal wall and the length and height of the bulb of the lateral claw. This suggests that the sole of the medial claw should be left an extra 3 mm thicker than previously recommended such that, after "levelling", the sole of the lateral claw remains thick enough to protect fully the corium and the claw retains a more normal shape.

A rapid and precise method for the quantitation of ethanol in serum using the EMIT St serum ethanol assay reagent and a Cobas Bio centrifugal analyser.

We describe a simple and rapid, but nevertheless precise and accurate method for measuring ethanol in serum, using the Roche Cobas Bio centrifugal analyser and the EMIT StTM serum ethanol assay reagent. Within-assay imprecision was 2.2% (CV), day-to-day imprecision was 2.5% (CV). The results correlated well with a commonly used gas chromatographic headspace method. Because of its rapidity and good practicability this method seems to be well suited for use in emergency care units of clinical chemistry laboratories.