Wastewater treatment by radial freezing with stirring effects

Radial freezing experiments on wastewater models were conducted in the presence of imposed stirring in order to remove impurities. The studied samples (dilute Na-montmorillonite suspensions charged with nitrates and with zinc or lead) were placed inside a cylindrical annulus, cooled at a controlled temperature around -7 degrees C at its inner wall which rotated around a vertical axis. The freezing front propagated toward the still outer wall which was maintained at a constant temperature around +1 degrees C. Thanks to stirring, considerable purification rates up to 99.97% were attained. It was also demonstrated that combining radial freezing and stirring ended in residual concentrations which agreed with drinking water standards.     

Boston harbor outfall tunnel: An environmental imperative

In February 1989, the Massachusetts Water Resource Authority (MWRA) began the design and construction of a 15.3-km subsea tunnel and ocean riser system to discharge effluent in conjunction with the design and construction of a large secondary treatment plant. The court-mandated schedule required the tunnel and risers to be completed in July 1995. The paper discusses the project from the viewpoints of management, concept design and construction methods, including the ocean riser system. Key to th success of the project is the accuracy of the location of the risers. The design calls for a final tunnel alignment to be driven within 10 m of the riser shafts, beginning at a distance of 13.1 km from shore.     

Spatial and temporal patterns of herd somatic cell score in france

Spatial and temporal patterns of annual milk somatic cell score (ASCS) were explored in French dairy herds between 1996 and 2000 to detect regional singularities for risk of mastitis. A new cluster detection method was used, which was adapted to continuous variables and which allowed ASCS variation factors to be taken into account. The statistical unit was the herd-year. A linear regression model for each year allowed adjustment for breed, mean parity, number of calvings for each season, herd size, and farm altitude. Cluster detection was performed on raw data and on residuals of the model through a method based on the Hellinger distance between spatial distributions. The Hellinger distance between farm distributions was computed at different levels of ASCS (or residuals). Temporal ASCS patterns were explored using a computation of correlations and comparisons between spatial structures of the different years. The general ASCS trend over the study period was a decrease. The global Hellinger distance, which was higher than what could have been randomly expected for each of the 5 yr, indicated a significant spatial cluster formation. Cluster mapping over the 5 yr identified several areas, which sometimes differed between detection using raw data and that using ASCS residuals. Temporal correlations between ASCS residuals for each year were positive and decreasing, and 1996 and 2000 appeared spatially different from the other years. The more affected areas were regions that were not specialized in dairy production. During the study period, 2 progressive movements were detected, corresponding to a disappearance of clusters in the northwest and an increase of clusters in the southwest. Cluster detection could aid in the identification of new risk factors that are relevant at different spatial scales, and could help local organizations to supervise the risk of mastitis, and improve udder health management.     

Tuning the Functional Properties of Polysaccharide–Protein Bio‐Based Edible Films by Chemical,Enzymatic, and Physical Cross‐Linking

Among natural biopolymers, polysaccharides and proteins are very promising for biodegradable and edible wraps with different characteristics, so that their formulations can be tailor‐made to suit the needs of a specific commodity. Films prepared from polysaccharides have good gas barrier properties but exhibit lower resistance to moisture compared to protein films (edible) or polylactide films (biodegradable). Protein‐based films show better mechanical and oxygen barrier properties compared to polysaccharide films. For that reason, film performances may be enhanced by producing blend systems, where hydrocolloids (mixtures of proteins and/or polysaccharides) form a continuous and more cohesive network. However, the lower water barrier properties of hydrocolloid films and their lower mechanical strength in comparison with synthetic polymers limit their applications in food packaging. Therefore, the enhancement of biopolymer film properties has been studied to attain appropriate applications. This review provides an extensive synthesis of the improvement of the properties of edible polysaccharide–protein films by way of various chemical, enzymatic, and physical methods. These methods primarily aim at improving the mechanical resistance. They also permit to ameliorate the water and gas barrier properties and related functional properties.     

Evaluation of most-probable-number-PCR method with internal amplification control for the counting of total and pathogenic Vibrio parahaemolyticus in frozen shrimps

The most-probable-number (MPN) method is often time-consuming for the isolation, detection, and quantification of Vibrio parahaemolyticus from natural sources. MPN counting of V. parahaemolyticus bacteria usually involves the isolation of typical V. parahaemolyticus colonies on selective medium, with subsequent confirmation by biochemical identification. In this study, we evaluated the use of a PCR on MPN enrichment cultures (MPN-PCR) for the direct detection of total and pathogenic V. parahaemolyticus cells in frozen shrimp. This reaction targeted the R72H, tdh, and trh sequences. An internal amplification control was added to the samples before R72H amplification. There was an excellent correlation between the results of the two methods for artificially inoculated and natural shrimp samples. Of 36 natural samples, 28 tested positive for the presence of V. parahaemolyticus, with an MPN value of 2 × 10(-1) to 9.2 × 10(1) per g. No pathogenic V. parahaemolyticus cells were detected. The test had a detection limit of one V. parahaemolyticus organism per g and was completed within two working days. These results support the use of the combination of PCR with MPN for the detection of total or potentially pathogenic V. parahaemolyticus cells in frozen shrimp.     

Working memory capacity and go/no-go task performance: Selective effects of updating, maintenance, and inhibition.

The ability to temporarily maintain information in order to successfully perform a task is important in many daily activities. However, the ability to quickly and accurately update existing mental representations in distracting situations is also imperative in many of these same circumstances. In the current studies, individuals varying in working memory capacity (WMC) performed different varieties of go/no-go tasks that have been hypothesized to measure inhibitory ability. The results indicated that low-WMC individuals relative to high-WMC individuals showed worse performance specifically in certain conditions of the conditional go/no-go task. Further analyses showed that increasing the temporal lag/number of intervening items between the previous target and the current lure had a deleterious effect on the performance of the low-WMC group only. The results indicate a relationship between WMC and the ability to selectively update, maintain, and retrieve information, especially in interference-rich conditions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Change of milk yield with clinical diseases for a high producing dairy herd

Changes in milk production associated with occurrence of clinical diseases (dystocia, stillbirth, twin births, milk fever, retained placenta, displaced abomasum, limping due to foot lesions, metritis, ketosis, and mastitis) were investigated. Data were collected daily on 388 lactation. Stepwise least squares regression was used to evaluate existence of associations between diseases and six yield measures that characterized milk production in the first 119 d postpartum. Logistic regression was used to investigate whether milk yield 1 to 5 d in milk might be of use to detect cows with early postpartum metritis (less than 21 d after calving). Lower milk production to 5 d postpartum was associated with an increased risk of early postpartum metritis in the logistic regression model. Yield to 5 and to 21 d postpartum was lower in cases of stillbirth, retained placenta, and early postpartum metritis. Yield from 22 to 49 d postpartum remained lower in cows diagnosed with early postpartum metritis. Milk yield losses occurred during diagnosis and treatment of displaced abomasum and mastitis. Ketosis was associated with yield losses prior to and at treatment. Ketosis to 21 d in milk was also associated with lower production after treatment. Limping diagnosed in the first 49 d postpartum coincided with higher yield to 5 d, to 21 d, and after 49 d postpartum.     

Impact of preheating on the behavior of Listeria monocytogenes in a broth that mimics Camembert cheese composition

The effect of preheating on the survival of L. monocytogenes in Richard's broth, which mimics the composition of Camembert cheese composition, was examined. Experiments were carried out to reproduce contamination of cheese with environmental heat-stressed cells of L. monocytogenes surviving hot-cleaning procedures. Cells in mid-log phase were heated for 30 min at 56 degrees C before being inoculated into Richard's broth. The pHs and temperatures of Richard's broth were chosen to recreate the conditions of curd dripping (pH 5, 25 degrees C), of the beginning of cheese ripening (pH 5, 12 degrees C), and of the beginning (pH 5, 4 degrees C) and the end (pH 7, 4 degrees C) of cheese storage. Immediately after heat treatment, the viability loss was especially high for strain 306715, which exhibited only 0.6% +/- 0.2% survival, compared with 22% +/- 8.7% for strain EGD. The percentages of the surviving heated cells that were injured were 93% +/- 8% for strain 306715 and 98% +/- 3% for strain EGD. The destruction of the surviving L. monocytogenes cells was accelerated when they encountered the pH and temperature conditions of Camembert cheese during manufacturing, ripening, and cold storage (pH 5 at 25, 12, and 4 degrees C, respectively). The multiplication of the surviving heated cells was retarded under favorable growth conditions similar to those of storage by the distributor and the consumer (pH 7 at 4 and 12 degrees C, respectively).     

Thermal malfunction criteria of fire safety electrical equipment in nuclear power plants

Malfunctions of nuclear power plants' (NPP) fire safety electrical equipment may be the consequence of a fire, leading to an increase of temperature and heat fluxes in a room and its adjacent ones. Electrical equipment manufacturers issue a so‐called ‘maximum temperature of normal operation’ under which a continuous function is guaranteed. However, this manufacturer temperature does not correspond to the notably higher real maximum operating temperature. Exactly knowing this temperature has two impacts: adequate selection of fire safety equipment and new fire probabilistic risk assessment (PRA) damage threshold. Those levels are today very conservative for performance‐based design: 40°C for electronic boards and 55°C for electromechanical materials. That is why Electricité de France, Research and Development Division (EDF R&D), performed several tests in the MILONGA facility to investigate the thermal malfunction levels of cabinet equipment classified as ‘Important for Safety’ by

• first defining what malfunction means, according to the material type and its required function;
• defining a relevant and reliable methodology of tests;
• testing a sample of electromechanical materials and electronic boards used in NPP and
• suggesting new temperature criteria for Fire PRA.

Although the equipment behaviour may be dependent upon the materials of construction and equipment layout, the main results are the malfunction temperatures of 130°C for electromechanical materials and 95°C for electronic boards. Copyright © 2012 John Wiley & Sons, Ltd.     

Plasma Etch Processes for Embedded FRAM Integration

We describe the etch processes used for integration of embedded ferroelectric random access memory (FRAM) within a standard CMOS logic flow. The ferroelectric module is inserted following front-end contact formation and prior to backend integration using only two additional mask levels: capacitor pattern and bi-level via pattern. The single-mask stack etch process employs a TiAlN hardmask to define Ir/IrO_x/PZT/IrO_x/Ir capacitors. Protective sidewalls can be formed using an etchback process. The bi-level via etch and subsequent metal fill processes complete the FRAM module formation. Functional 4 MB arrays embedded with 5 levels of Cu/FSG integration have been demonstrated.