Mortality salience and the spreading activation of worldview-relevant constructs: Exploring the cognitive architecture of terror management.

Seven experiments assessed the hypothesis derived from terror management theory that reminding people of their mortality would increase accessibility of constructs central to their worldview. Experiment 1 found that mortality primes, relative to control primes, increased accessibility of nationalistic constructs for men but not for women. Experiment 2 replicated this finding and also found that mortality salience increased romantic accessibility for women but not for men. Four subsequent experiments supported the role of unconscious death-related ideation in producing these effects. A final experiment demonstrated that situational primes can increase the accessibility of nationalistic constructs for women after mortality salience. The roles of situational cues and individual differences in the effects of exposure to death-related stimuli on worldview-relevant construct accessibility are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Depression, self-focused attention, and expectancies for positive and negative future life events for self and others.

In two studies, we examined depressed and nondepressed persons' judgments of the probability of future positive and negative life events occurring to themselves and to others. Study 1 demonstrated that depressed subjects were generally less optimistic than their nondepressed counterparts: Although nondepressed subjects rated positive events as more likely to happen to themselves than negative events, depressed subjects did not. In addition, relative to nondepressed subjects, depressed subjects rated positive events as less likely to occur to themselves and more likely to occur to others and negative events as more likely to occur to both self and others. Study 2 investigated the role that differential levels of self-focused attention might play in mediating these differences. On the basis of prior findings that depressed persons generally engage in higher levels of self-focus than nondepressed persons do and the notion that self-focus activates one's self-schema, we hypothesized that inducing depressed subjects to focus externally would attenuate their pessimistic tendencies. Data from Study 2 supported the hypothesis that high levels of self-focus partially mediate depressive pessimism: Whereas self-focused depressed subjects were more pessimistic than nondepressed subjects, externally focused depressed subjects were not. The role of attentional focus in maintaining these and other depressive pessimistic tendencies was discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Landscape features control river's confluences water quality and tributary fish composition

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klarälven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.     

Model-based control of titer and glycosylation in fed-batch mAb production: Modeling and control system development

Therapeutic monoclonal antibodies (mAbs) are typically manufactured using mammalian cell cultures in fed-batch bioreactors, with increasing emphasis on meeting productivity and product quality attribute targets that depend strongly on such process variables as nutrient feed rates and bioreactor operating conditions. In this article, we identify, categorize, and address the challenges of achieving both productivity and product quality goals simultaneously, by developing a multivariable, model-based control system that can satisfy multiple production objectives in a fed-batch cell culture process. Here, we discuss model development and present theoretical concepts of observability and controllability that are essential to understanding and handling effectively these intrinsic challenges. Subsequently, we evaluate via simulation the performance of the outer-loop model predictive control and demonstrate the overall capability to satisfy complex production objectives in a laboratory scale bioreactor, as a first step toward the ultimate goal of creating an advanced control system for fed-batch mAb manufacturing processes.     

EXPERIMENTAL EVALUATION OF SELECTIVITY IN SLOW AROMATIC CHLORINATIONS

A dispersion plug flow reactor model (DPFR) has been derived and experimentally verified to predict product distribution and selectivity for commercial aromatic halogenation reactions. From the model recommendations for process modifications to reduce the amounts of undesirable byproducts arising from similar reactions can be obtained. The selectivity of the monochlorinated product is shown to depend on kinetic and hydrodynamic parameters, mixing in the reactor and chlorine solubility. The pertinent variables are arranged in five dimensionless groups which include the kinetic and hydrodynamic Damkohler Numbers, the Peclet Number, ratio of the rate constants and the ratio of chlorine solubility to the inlet aromatic concentration.

A micro pilot plant which duplicates industrial conditions for benzene and toluene chlorination was constructed to test the DPFR model. Chlorination studies were performed under a range of conditions. Hydrodynamic parameters required for the model were obtained from published correlations. The model prediction of selectivity agreed within 8% for all the experimental results, and actually better than 5% for most runs.

A graphical technique which provides recommendations for reducing the dichlorinated products is presented along with examples for both the design of a reactor, and troubleshooting of an existing reactor system.     

Hydrogen evolution reaction measurements of dealloyed porous NiCu

Porous metals are of interest for their high surface area and potential for enhanced catalytic behavior. Electrodeposited NiCu thin films with a range of compositions were electrochemically dealloyed to selectively remove the Cu component. The film structure, composition, and reactivity of these samples were characterized both before and after the dealloying step using scanning electron microscopy, energy-dispersive spectroscopy, and electrochemical measurements. The catalytic behavior of the dealloyed porous Ni samples towards the hydrogen evolution reaction was measured and compared to that of the as-deposited samples. The dealloyed samples were generally more reactive than their as-deposited counterparts at low overpotentials, making the dealloying procedure a promising area of exploration for improved hydrogen evolution catalysts.     

Histone Tail Sequences Balance Their Role in Genetic Regulation and the Need To Protect DNA against Destruction in Nucleosome Core Particles Containing Abasic Sites

Abasic sites (AP) are produced 10 000 times per day in a single cell. Strand cleavage at AP is accelerated ≈100-fold within a nucleosome core particle (NCP) compared to free DNA. The lysine-rich N-terminal tails of histone proteins catalyze single-strand breaks through a mechanism used by base-excision-repair enzymes, despite the general dearth of glutamic acid, aspartic acid, and histidine—the amino acids that are typically responsible for deprotonation of Schiff base intermediates. Incorporating glutamic acid, aspartic acid, or histidine proximal to lysine residues in histone N-terminal tails increases AP reactivity as much as sixfold. The rate acceleration is due to more facile DNA cleavage of Schiff-base intermediates. These observations raise the possibility that histone proteins could have evolved to minimize the presence of histidine, glutamic acid, and aspartic acid in their lysine-rich N-terminal tails to guard against enhancing the toxic effects of DNA damage.     

Layered Antiferromagnetism Induces Large Negative Magnetoresistance in the van der Waals Semiconductor CrSBr

The recent discovery of magnetism within the family of exfoliatable van der Waals (vdW) compounds has attracted considerable interest in these materials for both fundamental research and technological applications. However, current vdW magnets are limited by their extreme sensitivity to air, low ordering temperatures, and poor charge transport properties. Here the magnetic and electronic properties of CrSBr are reported, an air-stable vdW antiferromagnetic semiconductor that readily cleaves perpendicular to the stacking axis. Below its Néel temperature, T_N = 132 ± 1 K, CrSBr adopts an A-type antiferromagnetic structure with each individual layer ferromagnetically ordered internally and the layers coupled antiferromagnetically along the stacking direction. Scanning tunneling spectroscopy and photoluminescence (PL) reveal that the electronic gap is Δ_E = 1.5 ± 0.2 eV with a corresponding PL peak centered at 1.25 ± 0.07 eV. Using magnetotransport measurements, strong coupling between magnetic order and transport properties in CrSBr is demonstrated, leading to a large negative magnetoresistance response that is unique among vdW materials. These findings establish CrSBr as a promising material platform for increasing the applicability of vdW magnets to the field of spin-based electronics.