Interpersonal problem-solving interactions of depressed adolescents and their parents.

Research to date suggests that the family plays a significant role in the development, perpetuation, and relapse of depression in its members. This study examined the videotaped interactions of parents with a depressed adolescent and control parents and youth during a conflictual, problem-solving task. In comparison with parents of nondepressed adolescents, parents of depressed adolescents engaged in higher rates of incongruent communication in which aversive content behavior was linked with positive affective behavior. Adolescent depressed content behavior led to greater suppression of parent aversive content behavior in nondepressed families than in depressed families. The findings argue that dysfunctional family communication may be associated with the development or maintenance of depression in the child. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conditions under which young children can hold two rules in mind and inhibit a prepotent response.

The day-night task requires saying "night" to a picture of the sun and "day" to a picture of the moon. In this investigation of why young children fail at this task, systematic variations of the task were administered to 96 children, half 4 years old and half 4 1/2 years old. Training children on the strategy of chunking the 2 rules into 1 ("say the opposite"), thus reducing memory load, did not help their performance. What helped was reducing the inhibitory demand by instructing them to say "dog" and "pig" (not "night" and "day") even though memory of 2 rules and inhibiting saying what the pictures represented were still required. Here the response to be activated and the response to be inhibited were unrelated. When the correct response was semantically related to, and the direct opposite of, the to-be-inhibited response, children performed poorly. Inserting a delay between stimulus and response helped even though that delay was filled with distraction. Young children apparently need several seconds to compute the answer on this task. Often they do not take the needed time; when forced to do so, they do well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Catalytic Asymmetric Heterogeneous Aziridination Using CuHY/bis(oxazoline): Effect of Reaction Conditions on Enantioselectivity

The copper-catalyzed aziridination of styrene with copper-exchanged zeolite HY (CuHY) and copper(II) triflate (trifluoromethanesulfonate) (Cu(OTf)₂) as catalysts is described using N-(p-tolylsulfonyl)imino]phenyliodinane (PhI=NTs) as the nitrene donor. The effects on the ee and yield of the aziridine when the catalyst is modified by the presence of a chiral bis(oxazoline) are investigated in detail. The heterogeneously catalyzed reaction under these conditions shows a slight, but significant, enhancement in ee with increasing conversion at 25 °C. This is not observed in the more rapid homogeneously catalyzed reaction under identical reaction conditions using PhINTs as the nitrene donor. The enhancement in ee is proposed to result from the preferential reaction of the (S)-aziridine with the Cu²⁺:bis(oxazoline) complex in the presence of PhI=NTs, leading to an enhancement of the (R)-aziridine in the remaining aziridine product.     

Survival of environmental and clinical strains of methicillin-resistant Staphylococcus aureus [MRSA] in marine and fresh waters

Recent studies have found variable levels of methicillin-resistant Staphylococcus aureus [MRSA] in marine water from temperate and warmer climates suggesting that temperature may play a role in survival of MRSA in the environment. The aim of the study was to compare the survival of clinical and environmental MRSA and MSSA strains in fresh and marine water incubated at 13 °C and 20 °C over 14 days. Seven different MRSA strains and the MSSA ATCC 25923 were tested. Individual strains were diluted in sterile saline to a 0.5 McFarland standard (10⁸ cfu/ml), serially diluted in duplicate to a final concentration of 10⁵ cfu/ml in pooled filter-sterilized marine or fresh water and incubated at 13 °C or 20 °C in the dark. The results of this study found that temperature and salinity are important factors in MRSA and MSSA survival; the decay rate was ∼28% higher at 20 °C versus 13 °C and ∼34-44% higher in fresh water versus marine water. There was no statistical difference between environmental and clinical MRSA strain survival [P = 0.138]. The study found that MRSA/MSSA survival was significantly longer in marine water at 13 °C typical of the Pacific Northwest, which may have important implications for recreational beach visitors in colder climates.     

When is a Hat a Mountain? The Material Religion of Gesar Bards’ Hats

Abstract

Based on interviews performed in Qinghai, this article examines the ritual for creating the “mountain hat” used by bards of Tibet’s Gesar epic in the Yushu and Golok provinces to argue for its importance in constructing local ideas of identity and authority. After introducing a typology of bardic hats, this paper relates the two-week ritual to make a “mountain hat” and analyses how it unites epic narrative, local ideas of place, and the authority of Buddhist institutions into a single, distinctive object used in the performance arena. Utilizing David Morgan’s work on embodiment and identity through the act of seeing, this article argues for the “mountain hat” as a microcosm of a religious imaginary that influences and shapes the viewer’s and the bard’s self-understanding. Additionally, this article considers the interpretation of the “mountain hat” and the religious imaginary it represents in the larger context of contemporary Tibet, where competing forms of economic and cultural authority challenge Tibetans’ experience. Ultimately, this article draws attention to the central role of ritual in constructing the “mountain hat” and imbuing it with the necessary symbolic complexes to become a potent visual object of identity.     

Modeling the Extraction Rate Coefficient for the Extraction of Yttrium by DEHPA Using Organic-Phase Recycle

ABSTRACT

Extraction of yttrium (Y) from sulfuric acid was studied using di(2-ethylhexyl) phosphate (DEHPA). A portion of the organic phase was recycled back into the mixer after extraction for the mixer to operate at a moderate organic-to-aqueous volumetric phase ratio while processing at a low organic-to-aqueous flow rate ratio. The effective performance of the mixer was evaluated when operating at different organic-phase flow fractions. To model the extraction rate coefficient, a 2-factor designed experiment was performed by conducting both equilibrium and mixer-settler tests. The organic-phase flow fraction was varied over four discrete levels while the extractant concentration was varied over three discrete levels. Increasing the organic-phase flow fraction yielded a continual increase in the extraction rate coefficient. In contrast, increasing the extractant concentration yielded an initial increase followed by a subsequent decrease in the extraction rate coefficient. The decline in the extraction rate coefficient was attributed to a decrease in the yttrium-extractant complex’s diffusion coefficient. High metal loading caused an elevated organic-phase viscosity and thus the low diffusion coefficient. An extraction rate coefficient model is proposed to describe the effects of extractant concentration, viscosity and organic-phase flow fraction. Mass transfer resistance was largely in the organic phase.     

An Advanced TALSPEAK Concept Using 2-Ethylhexylphosphonic Acid Mono-2-Ethylhexyl Ester as the Extractant

A method for separating the trivalent actinides and lanthanides is being developed using 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) as the extractant. The method is based on the preferential binding of the actinides in the aqueous phase by N-(2-hydroxyethyl)ethylenediamine-N,N’,N’-triacetic acid (HEDTA), which serves to keep the actinides in the aqueous phase while the lanthanides are extracted into an organic phase containing HEH[EHP]. The process is very robust, showing little dependence upon the pH or the HEH[EHP], HEDTA, and citrate concentrations over the ranges that might be expected in a nuclear fuel recycling plant. Single-stage runs with a 2-cm centrifugal contactor indicate that modifications to the process chemistry may be needed to increase the extraction rate for Sm, Eu, and Gd. The hydraulic properties of the system are favorable to application in centrifugal contactors.     

Early developments in the ability to understand the relation between stimulus and reward.

Delayed nonmatching to sample (DNMS) is used to test the recognition memory function dependent on the medial temporal lobe. Children cannot succeed on this task until about 21 months. Because robust recognition is present well before then, the late emergence of another ability must account for the late success on DNMS. Evidence is presented here that the critical late-maturing confidence is the ability to grasp the relation between stimulus and reward—that is, to understand that the stimulus is a symbol or marker for the reward. Infants of 9 and 12 months were tested on 3 conditions of DNMS. A sample object was presented. After a delay, the sample and a novel object appeared; choice of the novel object was rewarded. In the standard task, the reward was in a well beneath the stimulus. In the verbal-reward condition the reward was not a separate object but was praise and applause. In the Velcro condition, the reward, although a separate and separable object, was attached to the base of the stimulus. Most infants at both ages succeeded in the verbal-reward and Velcro conditions but not in the standard condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)