Coalescence model of particles in coaxial impinging streams

Coalescence is mainly affected by particle-to-particle collisions. A new model based on an equation expressing the condition for interparticle collision rate as well as the equation of motion of a single particle, has been developed for coaxial impinging streams. The model assumes that coalescence takes place only between small and large particles. In addition to the drag force usually influencing the behavior in impinging streams, the force acting on a large particle due to its collisions with small particles, has also been accounted for in the equation of motion. The effect of the change of the mass of the large particles on the acceleration due to coalescence with small particles, has also been included in the model. The model enables one to predict the composition of the product after coalescence from the composition of the feed and the operating conditions of the coalescentor.     

A mechanistic analysis of nitric oxide-induced cellular toxicity

Nitric oxide (NO.)-induced toxicity was investigated in two different cell lines, Chinese hamster ovary (CHO-AA8) and human lymphoblastoid (TK6), over a range of NO. doses (0-9 mM) delivered for an exposure of 2 h. To determine both short-term and delayed effects leading to death, a range of assays was employed to decipher the major mechanisms of cytotoxicity. Examples of damage parameters measured in this study include inhibition of DNA synthesis, damage to mitochondria, loss of cell membrane integrity, apoptosis, changes in cell cycle distribution, and the occurrence of DNA strand breaks. Our results indicate that NO.-induced toxicity is an extremely complex process involving multiple pathways generally leading to apoptotic cell death. Results consistently demonstrate that TK6 cells are much more susceptible to NO.-induced toxicity than CHO-AA8 cells. This difference in sensitivity could be seen for all types of cellular damage examined. The earliest observable effect of NO. exposure is inhibition of DNA synthesis which is not the result of inhibition of ribonucleotide reductase but may be the result of DNA damage leading ultimately to cell cycle arrest.     

Stochastic proximal linear method for structured non-convex problems

In this work, motivated by the challenging task of learning a deep neural network, we consider optimization problems that consist of minimizing a finite-sum of non-convex and non-smooth functions, where the non-smoothness appears as the maximum of non-convex functions with Lipschitz continuous gradient. Due to the large size of the sum, in practice, we focus here on stochastic first-order methods and propose the Stochastic Proximal Linear Method (SPLM) that is based on minimizing an appropriate majorizer at each iteration and is guaranteed to almost surely converge to a critical point of the objective function, where we also proves its convergence rate in finding critical points.     

Convergence of best-response dynamics in games with conflicting congestion effects

We study the model of resource allocation games with conflicting congestion effects that was introduced by Feldman and Tamir [9]. In this model, an agent's cost consists of its resource's load (which increases with congestion) and its share in the resource's activation cost (which decreases with congestion). The current work studies the convergence rate of best-response dynamics (BRD) in the case of homogeneous agents. Even within this simple setting, interesting phenomena arise. We show that, in contrast to standard congestion games with identical jobs and resources, the convergence rate of BRD under conflicting congestion effects might be super-linear in the number of jobs. Nevertheless, a specific form of BRD is proposed, which is guaranteed to converge in linear time.     

Effect of diffusivity on gas-side mass transfer coefficient

Experiments conducted in a stirred cell on evaporation of pure liquids into various carrier gases yield that the gas-side mass transfer coefficient, k_g is proportional to the binary diffusivity, D, raised to the power 0.684 (2-3).     

CHARACTERISTICS AND SCALE-UP OF COAXIAL IMPINGING STREAMS GAS - SOLID CONTACTORS

Scale-up rules and characteristic behavior were defined for coaxial impinging - stream reactors concerning the hydrodynamics, mean residence time and RTD of the particles and heat transfer in drying operations.     

Public health approaches to family maltreatment prevention: Resetting family psychology's sights from the home to the community.

The authors review recent trends within the family maltreatment research field toward a public health approach, discuss the rationale for community-level interventions for family maltreatment, and sketch the history and development of community-level prevention approaches. Next, to illustrate the both the logistic and the scientific challenges of such work, the authors discuss the development and testing of an empirically guided, research-community partnership for the prevention of family maltreatment, the United States Air Force's NORTH STAR initiative (New Orientation to Reduce Threats to Health From Secretive Problems That Affect Readiness). Finally, recommendations are made for effective and disseminable family maltreatment prevention interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time required to determine performance variables and production efficiency of lactating dairy cows

Thirty-five lactating dairy cows throughout weeks of lactation (WOL) 16 to 30 were used to determine optimal time needed for reliable measurement of performance variables, and to classify the cows into high-, medium-, and low-efficiency groups. Individual performance variables [body weight (BW), dry matter intake (DMI), and milk production] were measured daily with a computerized monitoring system. Body condition was visually scored weekly and used to calculate retained or depleted body energy as a result of fat content change (RE_F). Milk composition was analyzed weekly. Body weight, DMI, and total recovered energy (RE), which represents energy in milk production plus RE_F, were summarized weekly. Efficiency was calculated as RE/DMI and as residual feed intake (RFI; i.e., the difference between actual and expected DMI), which was calculated from multiple linear regression of DMI dependence on BW^0.75 and RE. Unexpectedly, it was found that BW did not affect DMI and RE/DMI. Changes and relative changes in phenotypic coefficient of variation and correlations among data from shortened tests ranging from 1 wk (WOL 16) to a sequence of 15-wk tests were used to determine optimal test period durations for 5 traits: BW, DMI, RE, RE/DMI, and RFI. Traits were fitted into a mixed model with repeated measures. For each week, the traits were summarized as a sequence of cumulative data, starting from WOL 16 and cumulated over periods that increased in 1-wk steps up to WOL 16 to 29. Weekly cumulations were compared with those for entire test period (WOL 16 to 30). Consistency of each cow’s efficiency classification as high, medium, or low was tested by the total-agreement procedure; the kappa index P-value was used. Throughout WOL 16 to 30, the effects of increasing test period duration on between-animal coefficient of variation differed with respect to the various performance variables and RE/DMI: it tended to change with respect to BW, did not change with respect to DMI, and decreased with respect to RE and RE/DMI. In conclusion, compared with a 15-wk study, a 2-wk study can classify RFI and RE/DMI to 3 efficiency levels, with an individual correlation coefficient of 0.6. When the study was carried out over 3 wk or more, the lowest significant index of the classification was P < 0.004, the lowest individual correlation coefficient was 0.65, and its lowest significance was P < 0.01. The current study indicated that the insignificant effect of the BW of dairy lactating cows on their DMI should be validated in more studies.