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Abstract: Objectives: Currently most abdominal aortic aneurysm screening programmes discharge patients with aortic diameter of less than 30 mm. However, sub-aneurysmal aortic dilatation (25 mm–29 mm) does not represent a normal aortic diameter. This observational study aimed to determine the outcomes of patients with screening detected sub aneurysmal aortic dilatation. Design and methods: Individual patient data was obtained from 8 screening programmes that had performed long term follow up of patients with sub aneurysmal aortic dilatation. Outcome measures recorded were the progression to true aneurysmal dilatation (aortic diameter 30 mm or greater), progression to size threshold for surgical intervention (55 mm) and aneurysm rupture. Results: Aortic measurements for 1696 men and women (median age 66 years at initial scan) with sub-aneurysmal aortae were obtained, median period of follow up was 4.0 years (range 0.1–19.0 years). Following Kaplan Meier and life table analysis 67.7% of patients with 5 complete years of surveillance reached an aortic diameter of 30 mm or greater however 0.9% had an aortic diameter of 54 mm. A total of 26.2% of patients with 10 complete years of follow up had an AAA of greater that 54 mm. Conclusion: Patients with sub-aneurysmal aortic dilatation are likely to progress and develop an AAA, although few will rupture or require surgical intervention. [Copyright &y& Elsevier]

Abstract: Highly active samarium doped zinc oxide self-cleaning and biocidal surfaces (x mol% Sm3+/ZnO where x =0, 1, 2 and 4mol%) with crystalline porous structures were synthesized by hydrothermal method. Sm3+/ZnO thin films were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), energy dispersive spectroscopic (EDS), UV–visible diffuse reflectance and fluorescence (FL) spectroscopy. The combination between doping and hydrothermal treatments significantly altered the morphology of ZnO into rod and plate-like nanoshapes structure and enhanced its absorption and emission of ultraviolet radiation. The photo-activity in term of quantitative determination of the active oxidative species ( OH) produced on the thin film surfaces was evaluated using fluorescent probe method. The results showed that, the hydrothermally treated 2.0mol% Sm3+/ZnO film (S2) is the highly active one. The optical, structural, morphology and photo-activity properties of the highly active thin film (S2) make it promising surface for self-cleaning and sterilizing applications. [Copyright &y& Elsevier]

Abstract: Lanthanide (Ln3+) doped TiO2 down-conversion photoelectrodes (Ln3+ =Eu3+ and Sm3+ ions) are used to enhance the photovoltaic efficiency of dye-sensitized solar cells (DSSC). We report on achieving fill factors of 0.67 and 0.69 and efficiencies of 5.81% and 5.16% for Sm3+ and Eu3+, respectively. This is compared to the 4.23% efficiency for the undoped-titania photoelectrodes. This enhancement is probably due to the improved UV radiation harvesting via a down-conversion luminescence process by the lanthanide ions. The structure, optical and photoluminescence properties of the down-converting photoelectrode are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX) and room temperature photoluminescence excitation and emission spectrofluorimetric measurements. [Copyright &y& Elsevier]

Abstract: Objectives: To determine predictors related to abdominal aortic aneurysm (AAA) development following a “normal” aortic ultrasound scan. Design, materials & methods: Over a 23-year period, 22 961 men participated in an AAA screening programme. Maximum aortic diameter of less than 30mm was deemed “normal”. 4308 of these “normal” individuals were later re-scanned at intervals for research purposes. Results: AAA prevalence was 4.4% at initial scanning. In those with a normal scan, 46 patients subsequently presented with AAAs incidentally detected and 120 (2.8%) had AAAs identified as part of the ongoing surveillance. The median initial aortic size of these 166 men was 25mm (range 15–29mm). Over the follow-up period, there have been 24 (14%) AAA-related deaths, 24 patients underwent successful AAA surgery and 36 died of unrelated causes. In those with an initial aortic diameter of <25mm who later developed an AAA, the odds ratio for AAA-related mortality was 2 (95% CI 1-4.1, p = 0.03, x 2). Conclusion: AAAs can develop following an initial “normal” scan and men with an aortic diameters of 25–29mm appear to be at greater risk. Surveillance for this sub-group may further reduce the incidence of undiagnosed AAA and AAA-related mortality. [Copyright &y& Elsevier]

Background: Candidate gene analysis has been frequently used in attempts to understand the pathological processes involved in many aspects of AAA disease. Methods: This paper sets out a systems approach to reviewing AAA candidate gene analysis studies, whilst, explaining the key principles and design limitations of this universally applied technique. In addition we have performed a meta-analysis of six gene polymorphisms (ACE I/D, MTHFR+677C>T, MMP9−1562C>T, Il-1Beta/3953C>T, eNOS 4a/4b & TIMP1/+434C>T) reported in multiple case control studies. Results and conclusions: Three of these polymorphisms were associated with a significant risk of AAA, ACE RR 1.33 [95% CI 1.20–1.48], MTHFR RR 1.14 [1.08–1.21] and MMP9 RR 1.09 [1.01–1.18]. These differences have been previously reported as equivocal, within a context of contradictory studies and as such this meta-analysis provides new evidence for their involvement in AAA disease. The plausibility of these findings is discussed within the context of a systems approach to the pathology of AAA disease. [Copyright &y& Elsevier]

Abstract: Pure and Ln3+ modified TiO2 photocatalysts (Ln3+ = Eu3+ or Sm3+ ions) synthesized by a sol–gel method as well as commercially available P25 were applied for photocatalytic generation of useful hydrocarbons and hydrogen from acetic acid. Structure and surface properties of the photocatalysts were characterized by XRD, UV–vis/DR, FT-IR and N2 adsorption–desorption measurements. The main gaseous products of CH3COOH decomposition were CH4 and CO2. Trace amounts of C2H6 and H2 were also detected in the reaction mixture. Moreover, it was observed that the quantities of all identified gases increased with elongation of irradiation time. The most active photocatalysts towards CH4 and H2 generation were Ln3+/TiO2 containing 0.05 mol % of Sm and Eu, respectively. The results revealed that the Ln3+ modification can improve the effectiveness of the photocatalysts compared to pure and commercially available TiO2 provided that a proper amount of modifying ions is used. [Copyright &y& Elsevier]

[Display omitted] • 40% more methane was recovered via "thermal hydrolysis + two-stage AD" process. • Integrated thermal and fermentation process achieved up to 40% COD solubilization. • Maximum VFAs recovery was achieved via sequential "thermal/fermentation process". • The produced VFAs primarily contained acetic, propionic, and isobutyric acids. • Fermentation reduced the adverse effect of thermally-formed intermediates on AD. The purpose of this research was to investigate the impact of two process configurations integrating two-phase anaerobic digestion (AD) of municipal sludge with thermal hydrolysis (TH). The TH was positioned either before or after the acidogenic fermentation phase. The fermentation process was carried out under the semi-continuous flow regime with a retention time of three days. The TH was done at a temperature of 170 °C and for 30 min. Among all the tested scenarios, the TH of sludge followed by the acidogenic fermentation resulted in the highest COD solubilization ratio (39.5%) and volatile fatty acids production (6,420 ± 400 mg/L), which was 630% and 500% more than that of the raw sludge, respectively. The sequential TH/fermentation process achieved 40% higher ultimate methane yield (240 mL/g COD) than the non-pretreated (raw) sludge. Positioning TH after the fermentation process reduced the ultimate methane yield to 231 240 mL/g COD, although it was still 32% higher than that of the raw sludge. The analysis of methane production rate and biodegradation kinetics data suggested the formation of refractory intermediates during the thermal process of sludge, which reduced the overall performance rate during the first week of the AD process. It was also revealed that acidogenic fermentation of thermally-processed sludge could diminish the adverse effect of the recalcitrant compounds formed during the thermal hydrolysis on the subsequent AD process. [ABSTRACT FROM AUTHOR]

In the present study the occurrence of turkey carcass alterations such as breast skin lesions, liver lesions, and swelling of the hock joint in turkeys reared in organic farms was investigated at slaughterhouses in Germany. The examinations included 1,860 turkey carcasses of 2 turkey lines Kelly Broad Breasted Bronze(BBB) (540 toms and 540 hens) and British United Turkeys (Big 6 and The Test Product 7) (780 hens). The results showed that breast skin lesions were rare (1.7%). On the other hand, liver lesions were a common finding in both hens and toms. Nearly half of all investigated turkeys were affected (49.3%). Swelling of the hock joint was detected in 17.3% of all investigated turkeys; the occurrence in Kelly BBB toms was significantly higher than in hens (toms: 28.7%; hens: 16.9%). In general, there were significant differences between the investigated flocks. Carcass lesions are a major animal welfare concern, which affect conventional and organic reared turkeys. Investigating the occurrence of carcass lesions provides the necessary precondition to establish a benchmarking system to evaluate and compare turkey farms. The aim is to reduce and/or eliminate these alterations in the long term in order to improve animal welfare. [ABSTRACT FROM AUTHOR]

In this research, the physiochemical characteristics of source separated organics (SSO) throughout a long-term period, along with their possible effects on anaerobic digestion (AD), acidogenic fermentation, and hydrolysis processes were investigated. Seasonal characteristics of SSO revealed significant differences in some factors demonstrating that eating habits, waste handling, and collection techniques would lead to the variation in SSO characteristics. The SSO collected during the summer months revealed a significantly higher yield for soluble COD based on the mass of volatile suspended solids (VSS) (428 mg/g-VSS) and volatile fatty acids (VFAs) production (292 mg COD VFAs/g-VSS) compared to those of the winter samples. The results revealed that 65–68% of the produced SCOD during the acidogenic fermentation process belonged to VFAs. It was also revealed that 85% of the VFAs was produced during the first two days of the fermentation process. The mesophilic batch AD process achieved based on the mass of volatile solids (VS) an average methane yield of 555 mL CH 4 /g VS, which was significantly higher than the range of 350–480 mL CH 4 /g-VS reported for food waste in the literature. Considering the results of the present study, the SSO has a significant potential to produce biomethane and VFAs at the industrial scale. The cost-benefit analysis of a full-scale AD plant with a capacity of processing 75,000 tonnes SSO/year revealed that the revenue from selling the SSO-derived CH 4 (∼400,000 $/year) could compensate for about 20% of the operating cost of the plant. Image 1 • The maximum volatile fatty acid (VFAs) yield of 292 mg/g VSS was achieved. • Up to 85% of the VFAs was produced during the first 2 days of the fermentation process. • An average methane yield of 555 mL CH 4 /g VS was obtained through the SSO digestion. • SSO revealed higher potential for methane production compared to food waste. • Selling biomethane could compensate for about 20% of the digester operating cost. [ABSTRACT FROM AUTHOR]

The present study shows the prevalence and severity of foot pad dermatitis (FPD) in turkeys reared in organic production systems assessed at slaughterhouses in Germany. The investigations of altogether 1,860 turkeys of the strains Kelly Broad Breasted Bronze (Kelly BBB; 540 toms, 540 hens) and British United Turkeys (B.U.T.) 6 and the Test Product 7 (TP 7; 780 hens) showed that 97.7% of the examined turkeys were diagnosed with different degrees of FPD. Only 4.6% of the toms and 1.3% of the hens had feet without lesions. Most frequent were necrotic lesions measuring up to 2 cm in diameter (64.3% of all turkeys). Extensive necrotic lesions of the foot pads (toms: 29.8%; hens: 12.4%) and necrosis of superficial scales (toms: 11.3%; hens: 7.6%) were less frequent. Plantar abscesses were rare findings (1.9%). In general, the feet of the Kelly BBB hens were more affected by foot pad lesions than those of the Kelly BBB toms. There were significant differences between the investigated flocks concerning the occurrence of foot pad lesions. The aim in rearing turkeys must be the reduction of FPD. [ABSTRACT FROM AUTHOR]

• Comparison of liquid and dewatered digestate to start up anaerobic digestion process. • Similar methane and biohydrogen yield for the two tested inocula. • Higher methane production rate of the digestate cake-inoculated digesters. • Up to 90% reduction in the transportation volume using digestate cake as inoculum. In this study, the application of liquid and dewatered digestate was compared for the inoculation of the anaerobic digestion (AD) process. In addition to the specific methanogenic activity and biohydrogen potential tests, biochemical methane potential assay was also conducted using four different types of municipal and industrial waste streams (primary sludge, thickened waste activated sludge, source separated organics, and cattle manure). The specific methanogenic activity of the digestate cake (5.0 ± 0.5 mL- C H 4 /g-VSS.d) was higher than that of the liquid digestate (3.4 ± 0.2 mL- C H 4 /g-VSS.d) for the food to microorganism ratio of 0.5. The BMP results also revealed that regardless of the type of the substrate used, the application of the digestate cake as inoculum achieved statistically significantly higher methane production rate compared to the utilization of liquid digestate, most likely due to the lower concentration of dissolved contents (i.e., ammonia, soluble organic matter, heavy metals, etc.) in the diluted digestate cake. Despite the increased process rate, no statistically significant effect of the type of the inoculum was observed on the ultimate methane yield. The biohydrogen potential test revealed the similar performance of the digestate- and digestate cake-inoculated digesters in terms of biohydrogen and volatile fatty acids production. The findings of this study suggest that the digestate cake can be used as an effective alternative to the liquid digestate for the inoculation of full-scale anaerobic digesters, reducing the transportation volume by up to 90%. [ABSTRACT FROM AUTHOR]

Highlights • Pretreatment of SSO was done at 150–240 °C under 5 different severity index values. • The maximum methane yield of 280 mL/g TCOD added was achieved at 190 °C. • Pretreatment improved solubilization and methane recovery by 50 & 26%, respectively. • A significant correlation was found between soluble COD and methane yield. • Pretreatment temperature beyond 200 °C decreased the methane yield. Abstract The objective of this research was to evaluate the effect of the hydrothermal pretreatment on the solubilization of source separated organics (SSO) as well as the biomethane recovery through the mesophilic batch anaerobic digestion process. For this purpose, the SSO was subjected to fifteen different pretreatment conditions within five different severity index (SI) values (3, 3.5, 4, 4.5, and 5). The pretreatment temperature, holding time, and pressure ranged from 150 to 240 °C, 5 to 30 min, and 476 to 3367 kPa, respectively. The highest solubilization improvement of ∼50% was achieved under the pretreatment condition of "220 °C-10 min-2323 kPa" corresponding to the SI value of 4.5. However, the maximum biomethane production yield of 280 mL/g TCOD added and biomethane production rate of 30 mL/g TCOD added were obtained under the less intense pretreatment conditions of "190 °C-20 min-1247 kPa" and "170 °C-30 min-786 kPa", respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fuel type and partially premixed level effects on burner stability. • Flame stability behaviour of different turbulence generator disks were investigated. • Impact of changing the disk slit diameter on equivalence ratio distributions was examined. Abstract The creation of a more stable flame along with the extension of flammability limits under lean mixture combustion was the main motivation to develop a new burner design, which has been investigated in this research. The current burner configuration was utilized to create a wide range of higher turbulent intensities and to produce different degrees of mixture inhomogeneity, which acted to promote minimum pollution, highest performance and higher flame stability. The burner stability assessment was investigated using two types of fuel: natural gas (NG) and liquefied petroleum gas (LPG). They were tested under different degrees of partial premixing, and two turbulence generator disks for lean mixture at an equivalence ratio of φ = 0.8 were used. Following this, the Laser Induced Breakdown Spectroscopy (LIBS) technique was utilized to characterize and quantify the impact of changing the disk slit diameter on the distributions profiles of equivalence ratio or mixture fraction for a NG/air partially premixed flame. A series of homogeneous NG/air mixtures with different equivalence ratios were used to obtain the correlations between the measured emission lines of LIBS spectra and the global flame equivalence ratio. Consequently, the emission spectral lines ratios of H/N, H/O and C/N + O were utilized to predict the equivalence ratio distributions. The results demonstrated that for all of the mixing lengths, NG/air mixture with larger disk generator diameter yielded the maximum burner stability, whilst the LPG/air mixture with a larger disk generator diameter resulted in the minimum burner stability. Furthermore, the flame associated with the larger disk slit diameter had a uniform local equivalence ratio distribution and lower RMS fluctuation profiles of equivalence ratio in comparison to the lower disk slit diameter. [ABSTRACT FROM AUTHOR]

A new burner was developed in order to achieve very stable lean flames at lower equivalence ratio and higher level of turbulence intensity. The air-fuel mixing process of the current burner was controlled either by using different levels of partially premixed or by changing the turbulence generator disk slit diameter, ds. Initially, the distributions of turbulent intensity and air volume fraction inside the burner were numerically investigated using three-dimensional computational fluid dynamic (CFD) modelling. Then the lean flame stability limits corresponding to the lean natural gas (NG)/air mixture at an equivalence ratio of φ = 0.6, under five degrees of partially premixed and two turbulent generators disk slit diameters were delineated. Based on the stability limits map, laser induced breakdown spectroscopy (LIBS) technique was employed for further quantitative measurements of the mixture fraction or the equivalence ratio distributions of NG/air mixture. The results indicated that the maximum burner stability for smaller ds was achieved at mixing length to diameter ratio (L/D) of 1:1, whilst for larger ds the maximum stability was achieved at L/D ratio of 2:1. Furthermore, the largest disk slit diameter yielded a homogeneous mixture fraction distribution and lower rms fluctuation, compared to that of lower disk slit diameter. Consequently, this improved the conduction effectiveness in preheating the unburned gases layers resulting in higher flame propagation speed. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare 2 testing methods for Salmonella in poultry. One-day-old specific-pathogen-free chicks were infected via crop installation with a Salmonella test strain (Salmonella Enterititis phage type 4; Bundesintitut für gesundheitlichen Verbraucherschutz und Veterinärmedizin-No. 01–00554; nalidixic acid resistant). Samples were collected at 7 sample occasions to redetect the agent from the animals and the environment. Using conventional techniques and PCR, the test strain was successively detected in the animals as well as in the environment of the flocks. In comparison, PCR was more effective. First positive findings were obtained from cloacal swabs at the third sampling occasion. Most frequently Salmonella was obtained from ceca and from spleen samples, indicating that these 2 organs are most suitable for Salmonella testing. Cloacal swabs were positive earlier; however, ceca and spleen samples were positive more consistently. Conventional methods as well as PCR were suitable for detection of Salmonella. [ABSTRACT FROM PUBLISHER]

In the present study, the prevalence of vancomycin-resistant enterococci (VRE) in turkeys in the southwest of Germany was investigated. For this purpose, 200 cloacal swab samples and 5 environmental dust samples (tested as a pooled sample) of each of the 20 flocks (10 female and 10 male flocks) included in this study were examined. The VRE could be isolated by means of a procedure combining bacterial cultivation in an enrichment broth and on a selective solid media. Enterococci were identified biochemically and subsequently tested on the presence of the vancomycin resistance genes vanA, vanB (B1/B2/B3), and vanC (CI/ C2/C3) using real-time PCR assays. In 54 (27%) turkeys originating from 11 (55%) flocks and in 14 (70%) of the dust samples, exclusively vanA and vanCl genes could be detected. Of the turkeys examined, 46 were colonized with VRE bearing the resistance gene vanCl and 8 vanA, originating from 9 and 2 flocks, respectively. None of the birds carried vanB, vanC2, or vanCS positive VRE. The results obtained from the birds are largely confirmed by the dust samples originating from 4 vanA and 10 vanCl positive flocks. However, one flock housing animals colonized with vanCl positive VRE could not be confirmed by the dust samples that revealed vanA bearing VRE. However, in one case vanA and in 3 cases vanCl carrying VRE could be detected in dust samples of the turkey houses, but not in the turkeys of the associated flock. In 5 flocks the turkeys as well as the dust samples were free of VRE. [ABSTRACT FROM AUTHOR]

Two turkey flocks (male and female) and the environment of their house were investigated for the presence of thermophilic Campylobacter. Sample DNA was extracted directly from fecal material and environmental samples. Bacterial identification was done using a modified Campylobacter species specific multiplex PCR. The times needed for colonization and prevalence in male and female turkeys were determined independently. All environmental samples collected before restocking were negative in the PCR analysis, showing a good hygiene and biosecurity system. The first positive PCR results were obtained in drinking water samples at 6 d of age. Colonization occurred between the second and third week of age, starting in female birds and then followed by the males. Campylobacter jejuni was detected by multiplex PCR at first; later on, Campylobacter coli and mixtures of both were seen. After the 9 wk of age, the colonization of the flocks was completed. Great attention should be given to drinking water as a supposed source of Campylobacter contamination. Multiplex PCR proved to be a rapid, sensitive, and cheap tool for the diagnosis of Campylobacter contamination. [ABSTRACT FROM AUTHOR]

Abstract: In the present position paper, an attempt was made to establish clinical breakpoints of amoxicillin to classify porcine respiratory tract pathogens as susceptible, intermediate or resistant based on their minimum inhibitory concentrations of amoxicillin. For this, a thorough review of the published literature with regard to swine-specific pharmacological data (including dosages of amoxicillin applied and routes of administration used), clinical efficacy, and in vitro susceptibility of the target pathogens was performed. Based on the comparative analysis of the results, the working group “Antibiotic Resistance” of the German Veterinary Medical Society (DVG) proposed to classify porcine respiratory tract pathogens that show MIC values of amoxicillin of ≤0.5μg/ml as “susceptible”, those with MICs of 1μg/ml as “intermediate”, and those with MICs of ≥2μg/ml as “resistant”. [Copyright &y& Elsevier]

This research aims to provide new insights into the performance and the microbial dynamics of the sludge fermentation process coupled with thermal hydrolysis. Two semi-continuous fermenters were operated under the mesophilic and thermophilic conditions at the retention time of three days. Thermal hydrolysis (TH) was applied either before (pre-hydrolysis) or after (post-hydrolysis) the fermentation process at a temperature, pressure, and stationary time of 170 °C, 115 psi, and 30 min, respectively. The process incorporating pre-hydrolysis achieved 10–16% higher solubilization and volatile fatty acids (VFAs) production than that of post-hydrolysis. Acetate and propionate prevailed in both process schemes. However, significantly higher iso-butyrate and lower butyrate were recovered through the fermentation of pre-hydrolyzed sludge. Pre-hydrolysis stimulated the growth of more kinetically efficient fermentative bacteria such as Bacteroidetes and Firmicutes due to the abundance of soluble organic matters; however, it reduced the overall microbial diversity. The findings of this research suggest that coupling TH and acidogenic fermentation can provide an opportunity to enhance the production of soluble organics (e.g., VFAs) from wastewater sludge, which can be utilized for various applications including as an external carbon source for the on-site biological nutrient removal. Image 1 • Thermal hydrolysis stimulated the growth of more kinetically-efficient fermentative bacteria. • The population of Firmicutes and Proteobacteria was increased at the thermophilic condition. • The microbial community was less diverse in fermenters fed with thermally-hydrolyzed sludge. • 30% more VFAs were recovered through thermophilic fermentation than that of mesophilic. • Butyrate and iso-butyrate content of VFAs was substantially affected by thermal hydrolysis. [ABSTRACT FROM AUTHOR]