Experimental investigation of woody and non-woody biomass combustion in a bubbling fluidised bed combustor focusing on gaseous emissions and temperature profiles

Air staging is a well-known effective method to control NOx emissions from solid fuel combustion boilers. However, further research is still needed to clarify the effect of air staging at different injection locations on the gaseous emissions of Fluidised Bed Combustion (FBC) boilers that fire 100% biomass fuels, particularly non-woody biomass fuels. The main objective of this work is to investigate the effect of the staging air injection location on the gaseous emissions (NOx and CO) and temperature profiles of a 20 kWth bubbling fluidised bed combustor firing three non-woody (straw, miscanthus and peanuts) and two woody biomass fuels. The experimental results showed that injecting the secondary air at the higher location could lead to a greater NOx reduction due to the fact that the biomass combustion reaction mainly took place in the splash zone and/or beginning of the freeboard. Up to 30% of NOx reduction, compared with no air staging, was achieved for the non-woody fuels when the staging air was injected at the higher position. Air staging also significantly reduced the CO emissions as a result of the higher temperatures in the freeboard and longer residence time in the primary combustion zone

Oxy-fuel combustion study of biomass fuels in a 20 kWth fluidized bed combustor

Oxy-fuel combustion is one of the promising carbon capture technologies considered to be suitable for future commercial applications with stationary combustion plants. Although more and more biomass and waste are now being burned in stationary combustion plants, research on oxy-fuel combustion of biomass has received much less attention in comparison to oxy-fuel combustion of coal. In this work, a series of tests was carried out in a 20 kWth fluidized bed combustor under oxy-fuel conditions firing two non-woody fuels (miscanthus and straw pellets) and one woody fuel (domestic wood pellet). The effects of the combustion atmosphere (air and oxy-fuel) and oxygen concentration in the oxidant of the oxy-fuel combustion on gas emissions and temperature profiles were systematically studied with the overall excess oxygen coefficient in the combustor being maintained roughly constant throughout the tests. The experimental results showed that replacing the air with an oxy-fuel oxidant of 21 vol% O2 and 79 vol% CO2 resulted in a significant decrease in combustion temperature and ultimately led to the extinction of the biomass flame due to the larger specific heat of CO2 compared to N2. To keep a similar temperature profile to that achieved under the air combustion conditions, the oxygen concentration in the oxidant of O2/CO2 mixture had to be increased to 30 vol%. A drastic decrease in CO emissions was observed for all three biomass fuels (up to 80% reduction when firing straw) under oxy-fuel combustion conditions providing that the oxygen concentration in the oxidant of O2/CO2 mixture was above 25 vol%. NOx emissions were found to decrease with the oxygen concentration in the oxy-fuel oxidant, due to i) the increase of bed temperature, which implies more volatile-N released and converted in the dense bed zone and ii) the less dilution of the gases inside the dense bed zone, which leads to a higher CO concentration in this region enhancing the reduction of NOx. Similar NOx emissions to those obtained with air combustion were found when the oxygen concentration in the oxy-fuel oxidant was kept at 30 vol%. Further analysis of the experimental results showed that the gas emissions when firing the non-woody fuels were controlled mainly by the freeboard temperature instead of the dense bed region temperature due to the characteristically high volatile matter content and fines of this kind of biomass fuels

Clinical Study Doxapram Use for Apnoea of Prematurity in Neonatal Intensive Care

Apnoea of prematurity is treated with noninvasive respiratory therapy and methylxanthines. For therapy unresponsive apnoea doxapram is often prescibed in preterm neonates. The duration, dosage and route of administration of doxapram together with its efficacy was evaluated in two Dutch neonatal intensive care. Outcome concerning short-term safety and neonatal morbidity were evaluated. During 5 years, 122 of 1,501 admitted newborns <32 weeks of gestational age received doxapram. 64.8% of patients did not need intubation after doxapram. 25% of treated neonates were <27 weeks of gestation. A positive response to doxapram therapy on apnoea was associated with longer duration of doxapram usage ( < 0.001), lower mean doses ( < 0.003), and less days of intensive care (median 33 versus 42 days; < 0.002). No patients died during doxapram therapy. Incidence of necrotizing enterocolitis, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, persistent ductus arteriosus, or worsening of pulmonary condition did not increase during doxapram therapy. Doxapram is frequently used for apnoea of prematurity, despite a lack of data on short-term efficacy and long-term safety. Until efficacy and safety are confirmed in prospective trials, doxapram should be used with caution

Experimental investigations on the Chlorine-induced corrosion of HVOF thermal sprayed Stellite-6 and NiAl coatings with fluidised bed biomass/anthracite combustion systems

Stellite-6 (Co-based) and NiAl coatings (Ni-based) were deposited via HVOF spraying onto 304 stainless steels and tested in a 20 kWth biomass fired bubbling fluidised bed (BFB) combustor for 20 hours and an industrial scale anthracite fired CFB boiler for 1630 hours. Stellite-6 showed excellent corrosion resistance in both fluidised bed combustion systems because of the formation of outermost Cr2O3 layer and the spinel CoCr2O4 beneath, whereas NiAl coatings' anti-corrosion performance was significantly depleted due to the chlorine attack, and the resultant formation of Al2O3 layer at the coating/substrate interface finally led to coating spallation in both systems

A role for the collagen I/III and MMP-1/-13 genes in primary inguinal hernia?

BACKGROUND: Abnormal collagen metabolism is thought to play an important role in the development of primary inguinal hernia. This is underlined by detection of altered collagen metabolism and structural changes of the tissue in patients with primary inguinal hernia. However, it is still unknown whether these alterations reflect a basic dysfunction of the collagen synthesis, or of collagen degradation. METHODS: In the present study, we analysed type I and type III procollagen messenger ribonucleic acid (mRNA) and MMP-1 and MMP-13 mRNA in cultured fibroblasts from the skin of patients with primary inguinal hernia, and from patients without hernia (controls) by reverse transcription polymerase chain reaction (RT-PCR) and Northern Blot. RESULTS: The results indicated that the ratio of type I to type III procollagen mRNA was decreased in patients with primary hernia, showing significant differences as compared to controls (p = 0.01). This decrease was mainly due to the increase of type III procollagen mRNA. Furthermore, RT-PCR analysis revealed that the expression of MMP-1 mRNA in patients with primary hernia is equivalent to that of controls (p > 0.05). In addition, MMP-13 mRNA is expressed neither in patients with primary hernia nor in controls. CONCLUSION: We concluded that abnormal change of type I and type III collagen mRNAs contribute to the development of primary inguinal hernia, whereas the expressions of MMP-1 and MMP-13 mRNA appears not to be involved in the development of primary inguinal hernia. Thus, the knowledge on the transcriptional regulation of collagen in patients with primary inguinal hernia may help to understand the pathogenesis of primary inguinal hernia, and implies new therapeutic strategies for this disease

The effect of antipsychotic medication on sexual function and serum prolactin levels in community-treated schizophrenic patients: results from the Schizophrenia Trial of Aripiprazole (STAR) study (NCT00237913)

<p>Abstract</p> <p>Background</p> <p>The aim of this paper is to evaluate the effect of antipsychotics for the treatment of schizophrenia in a community based study on sexual function and prolactin levels comparing the use of aripiprazole and standard of care (SOC), which was a limited choice of three widely used and available antipsychotics (olanzapine, quetiapine or risperidone) (The Schizophrenia Trial of Aripiprazole [STAR] study [NCT00237913]).</p> <p>Method</p> <p>This open-label, 26-week, multi-centre, randomised study compared aripiprazole to SOC (olanzapine, quetiapine or risperidone) in patients with schizophrenia (DSM-IV-TR criteria). The primary effectiveness variable was the mean total score of the Investigator Assessment Questionnaire (IAQ) at Week 26. The outcome research variables included the Arizona Sexual Experience scale (ASEX). This along with the data collected on serum prolactin levels at week 4, 8, 12, 18 and 26 will be the focus of this paper.</p> <p>Results</p> <p>A total of 555 patients were randomised to receive aripiprazole (n = 284) or SOC (n = 271). Both treatment groups experienced improvements in sexual function from baseline ASEX assessments. However at 8 weeks the aripiprazole treatment group reported significantly greater improvement compared with the SOC group (p = 0.007; OC). Although baseline mean serum prolactin levels were similar in the two treatment groups (43.4 mg/dL in the aripiprazole group and 42.3 mg/dL in the SOC group, p = NS) at Week 26 OC, mean decreases in serum prolactin were 34.2 mg/dL in the aripiprazole group, compared with 13.3 mg/dL in the SOC group (p < 0.001).</p> <p>Conclusion</p> <p>The study findings suggest that aripiprazole has the potential to reduce sexual dysfunction, which in turn might improve patient compliance.</p

Hernia fibroblasts lack β-estradiol induced alterations of collagen gene expression

BACKGROUND: Estrogens are reported to increase type I and type III collagen deposition and to regulate Metalloproteinase 2 (MMP-2) expression. These proteins are reported to be dysregulated in incisional hernia formation resulting in a significantly decreased type I to III ratio. We aimed to evaluate the β-estradiol mediated regulation of type I and type III collagen genes as well as MMP-2 gene expression in fibroblasts derived from patients with or without history of recurrent incisional hernia disease. We compared primary fibroblast cultures from male/female subjects without/without incisional hernia disease. RESULTS: Incisional hernia fibroblasts (IHFs) revealed a decreased type I/III collagen mRNA ratio. Whereas fibroblasts from healthy female donors responded to β-estradiol, type I and type III gene transcription is not affected in fibroblasts from males or affected females. Furthermore β-estradiol had no influence on the impaired type I to III collagen ratio in fibroblasts from recurrent hernia patients. CONCLUSION: Our results suggest that β-estradiol does not restore the imbaired balance of type I/III collagen in incisional hernia fibroblasts. Furthermore, the individual was identified as an independent factor for the β-estradiol induced alterations of collagen gene expression. The observation of gender specific β-estradiol-dependent changes of collagen gene expression in vitro is of significance for future studies of cellular response

Blau syndrome : cross-sectional data from a multicentre study of clinical, radiological and functional outcomes

OBJECTIVE: To report baseline articular, functional and ocular findings of the first international prospective cohort study of Blau syndrome (BS). METHODS: Three-year, multicentre, observational study on articular, functional (HAQ, Childhood HAQ and VAS global and pain), ophthalmological, therapeutic and radiological data in BS patients. RESULTS: Baseline data on the first 31 recruited patients (12 females and 19 males) from 18 centres in 11 countries are presented. Of the 31 patients, 11 carried the p.R334W NOD2 mutation, 9 the p.R334Q and 11 various other NOD2 missense mutations; 20 patients were sporadic and 11 from five BS pedigrees. Median disease duration was 12.8 years (1.1-57). Arthritis, documented in all but one patient, was oligoarticular in 7, polyarticular in 23. The median active joint count was 21. Functional capacity was normal in 41%, mildly impaired in 31% and moderate-severe in 28% of patients. The most frequently involved joints at presentation were wrists, ankles, knees and PIPs. On radiographs, a symmetrical non-erosive arthropathy was shown. Previously unknown dysplastic bony changes were found in two-thirds of patients. Ocular disease was documented in 25 of 31 patients, with vitreous inflammation in 64% and moderate-severe visual loss in 33%. Expanded manifestations (visceral, vascular) beyond the classic clinical triad were seen in 52%. CONCLUSION: BS is associated with severe ocular and articular morbidity. Visceral involvement is common and may be life-threatening. Bone dysplastic changes may show diagnostic value and suggest a previously unknown role of NOD2 in bone morphogenesis. BS is resistant to current drugs, suggesting the need for novel targeted therapies

Joint Mobility in Adult Patients with Groin Hernias

The basic mechanisms of hernia formation remain mostly unknown, but several studies suggest that a connective-tissue pathology, affecting mainly the collagen metabolism, could play a role in the genesis of groin hernias. It would be interesting to know if this pathology can express some clinical signs other than the hernia. Our study focused on the joint mobility and the diagnostic criteria for benign joint hypermobility syndrome. Sixty male adult patients with inguinal hernias and 62 control subjects without hernias, age-matched, were compared, taking into account anamnestic criteria (family history of groin hernia, joint sprain, joint dislocation, skin striae, major arthralgia) and joint mobility. This was assessed by using Beighton criteria and measuring the range of movement of five joints (extension of the fifth finger, thumb, wrist, elbow, and knee). The frequency of the positive anamnestic criteria was not statistically different between the two groups. Nevertheless, a family history of groin hernia was observed in 25% of the hernia patients, against 16% in the control subjects ( P=0.23). The mean Beighton score was 0.30 in the hernia patients and 0.29 in the control population. The movement range of the five examined joints was similar in the two groups. In conclusion, patients with a groin hernia presented neither joint hypermobility nor clinical evidence of a benign joint hypermobility syndrome. Although abnormal collagen metabolism is likely implicated in hernia formation, this pathology does not seem to have clinical repercussion on joint mobility