Temperamental resistance to control increases the association between sleep problems and externalizing behavior development.

This study examined the moderating effects of temperamental resistance to control on the link between development of sleep problems and development of externalizing behaviors over a 5-year period. Resistance to control was assessed with mothers' retrospective reports of temperament in infancy, provided when children were 5 years of age. Sleep problems were assessed with mother reports on an annual basis from age 5 to age 9. Externalizing behaviors were assessed with teacher reports on an annual basis from age 5 to age 9. A cross-domain latent growth curve model indicated that sleep problem trajectories were positively associated with externalizing behavior trajectories only for children high in resistance to control. In addition, resistance to control was positively associated with initial (age 5) sleep problems and initial (age 5) externalizing behaviors. The authors speculate that the development of sleep problems promotes the development of behavior problems for resistant children, whose self-regulatory abilities are especially tenuous. Implications for prevention and treatment of conduct problems are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A randomized controlled trial of filgrastim during remission induction and consolidation chemotherapy for adults with acute lymphoblastic leukemia: CALGB study 9111

Recombinant human granulocyte colony-stimulating factor (G-CSF; filgrastim) shortens the time to neutrophil recovery after intensive chemotherapy, but its role in the treatment of adults with acute lymphoblastic leukemia (ALL) is uncertain. We randomly assigned 198 adults with untreated ALL (median age, 35 years; range, 16 to 83) to receive either placebo or G-CSF (5 microgram/kg/d) subcutaneously, beginning 4 days after starting intensive remission induction chemotherapy and continuing until the neutrophil count was >/=1, 000/microL for 2 days. The study assignment was unblinded as individual patients achieved a complete remission (CR). Patients initially assigned to G-CSF then continued to receive G-CSF through 2 monthly courses of consolidation therapy. Patients assigned to placebo received no further study drug. The median time to recover neutrophils >/=1,000/microL during the remission induction course was 16 days (interquartile range [IQR], 15 to 18 days) for the patients assigned to receive G-CSF and 22 days (IQR, 19 to 29 days) for the patients assigned to placebo (P < .001). Patients in the G-CSF group had significantly shorter durations of neutropenia (<1, 000/microL) and thrombocytopenia (<50,000/microL) and fewer days in the hospital (median, 22 days v 28 days; P = .02) compared with patients receiving placebo. The patients assigned to receive G-CSF had a higher CR rate and fewer deaths during remission induction than did those receiving placebo (P = .04 by the chi-square test for trend). During Courses IIA and IIB of consolidation treatment, patients in the G-CSF group had significantly more rapid recovery of neutrophils >/=1,000/microL than did the control group by approximately 6 to 9 days. However, the patients in the G-CSF group did not complete the planned first 3 months of chemotherapy any more rapidly than did the patients in the placebo group. Overall toxicity was not lessened by the use of G-CSF. After a median follow-up of 4. 7 years, there were no significant differences in either the disease-free survival (P = .53) or the overall survival (P = .25) for the patients assigned to G-CSF (medians, 2.3 years and 2.4 years, respectively) compared with those assigned to placebo (medians, 1.7 and 1.8 years, respectively). Adults who received intensive chemotherapy for ALL benefited from G-CSF treatment, but its use did not markedly affect the ultimate outcome.     

Towards a continuous microfluidic rheometer

In a previous paper we presented a way to measure the rheological properties of complex fluids on a microfluidic chip (Guillot et al., Langmuir 22:6438, 2006). The principle of our method is to use parallel flows between two immiscible fluids as a pressure sensor. In fact, in a such flow, both fluids flow side by side and the size occupied by each fluid stream depends only on both flow rates and on both viscosities. We use this property to measure the viscosity of one fluid knowing the viscosity of the other one, both flow rates and the relative size of both streams in a cross-section. We showed that using a less viscous fluid as a reference fluid allows to define a mean shear rate with a low standard deviation in the other fluid. This method allows us to measure the flow curve of a fluid with less than 250 μL of fluid. In this paper we implement this principle in a fully automated set up which controls the flow rate, analyzes the picture and calculates the mean shear rate and the viscosity of the studied fluid. We present results obtained for Newtonian fluids and complex fluids using this set up and we compare our data with cone and plate rheometer measurements. By adding a mixing stage in the fluidic network we show how this set up can be used to characterize in a continuous way the evolution of the rheological properties as a function of the formulation composition. We illustrate this by measuring the rheological curve of four formulations of polyethylene oxide solution with only 1.3 mL of concentrated polyethylene oxide solution. This method could be very useful in screening processes where the viscosity range and the behavior of the fluid to an applied stress must be evaluated.     

A microfluidic platform using molecular beacon-based temperature calibration for thermal dehybridization of surface-bound DNA

This work presents a simple microfluidic device with an integrated thin-film heater for studies of DNA hybridization kinetics and double-stranded DNA melting temperature measurements. The heating characteristics of the device were evaluated with a novel, noninvasive indirect technique using molecular beacons as temperature probes inside reaction chambers. This is the first microfluidic device in which thermal dehybridization of surface-bound oligonucleotides was performed for measurement of double-stranded DNA melting temperatures with +/- 1 degrees C precision. Surface modification and oligonucleotide immobilization were performed by continuously flowing reagents through the microchannels. The resulting reproducibility of oligonucleotide surface densities, at 9% RSD, was better than for the same modification chemistries on glass slides in unstirred reagent solutions (RSD=20%). Moreover, the surface density of immobilized DNA probe molecules could be varied controllably by changing the concentration of the reagent solution used for immobilization. Thus, excellent control of surface characteristics was made possible, something which is often difficult to achieve with larger devices. Solid-phase hybridization reactions, a fundamental aspect of microarray technologies often taking several hours in conventional systems, were reduced to minutes in this device. It was also possible to determine forward rate constants for hybridization, k. These varied from 820,000 to 72,000 M(-1) s(-1), decreasing as surface densities increased. Surface densities could therefore be optimized to obtain rapid hybridization using such an approach. Taken together, this combined microfluidic/small-volume heating approach represents a powerful tool for surface-based DNA analysis.     

Situational approach to the assessment of social competence in children.

Generated and evaluated a taxonomy of the situations and tasks most likely to lead deviant children to experience social difficulties. In Study 1, elementary school teachers and clinicians were asked to notice such situations as they occurred. The outcome was a 44-item taxonomy of problematic social situations for children. This survey was administered to teachers of 45 socially rejected children (79% male) from Grades 3–5 and 39 adaptive children of the opposite sociometric criteria who were matched by sex and age to the rejected Ss. The survey was found to have high internal consistency and high test–retest reliability. Six situation types emerged as factors in analyses: Peer Group Entry, Response to Peer Provocations, Response to Failure, Response to Success, Social Expectations, and Teacher Expectations. Teachers rated the rejected group as having more problems than the adaptive group in each situation, but particularly in Response to Peer Provocations and Teacher Expectations. In Study 2, 15 items within the 6 factors were presented in a hypothetical format to 39 clinic-referred rejected aggressive children (77% males) from Grades 3–5 and 34 adaptive children selected by opposite criteria and matched by sex and age to the rejected aggressive Ss, who were asked to role play their responses. The items, in particular the provocation items, again differentiated the 2 groups. Sex and age differences were also found. The usefulness of this taxonomy in a 3-step model of clinical assessment is proposed. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

College student employment and drinking: A daily study of work stressors, alcohol expectancies, and alcohol consumption.

We examined the within-person relationships between daily work stressors and alcohol consumption over 14 consecutive days in a sample of 106 employed college students. Using a tension reduction theoretical framework, we predicted that exposure to work stressors would increase alcohol consumption by employed college students, particularly for men and those with stronger daily expectancies about the tension reducing properties of alcohol. After controlling for day of the week, we found that hours worked were positively related to number of drinks consumed. Workload was unrelated to alcohol consumption, and work-school conflict was negatively related to consumption, particularly when students expressed strong beliefs in the tension reducing properties of alcohol. There was no evidence that the effects of work stressors were moderated by sex. The results illustrate that employment during the academic year plays a significant role in college student drinking and suggest that the employment context may be an appropriate intervention site to address the problem of student drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prevalence and predictors of posttraumatic stress in women undergoing an ovarian cancer investigation.

This study assessed posttraumatic stress disorder (PTSD) in women being investigated for an ovarian cancer diagnosis to determine prevalence and factors predicting PTSD in these patients. Participants (N = 75) were recruited from the Princess Margaret Hospital in Toronto, Ontario, after their initial clinic appointment and given a prediagnostic assessment that included measures of PTSD, depression, stress and pain. One month later, patients received an identical postdiagnostic assessment. No cases of clinical PTSD were detected, although 13.6% of participants were identified with subsyndromal PTSD. Multiple regression analyses showed that those participants reporting significant baseline depressive symptoms, definitively diagnosed with ovarian cancer, and with shorter treatment wait times were more likely to have a significant increase in PTSD symptoms. Supportive interventions aimed at reducing PTSD symptoms, launched prior to an ovarian cancer diagnosis, might optimally be directed at patients with baseline depressive symptoms and those with shorter treatment wait times. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's Mental Health as a Primary Care and Concern: A System for Comprehensive Support and Service.

In response to the serious crisis in mental health care for children in the United States, this article proposes as a priority for psychology a comprehensive approach that treats mental health as a primary issue in child health and welfare. Consistent with the principles of a system of care and applying epidemiological, risk-development, and intervention-research findings, this approach emphasizes 4 components: easy access to effective professional clinical services for children exhibiting disorders; further development and application of sound prevention principles for high-risk youths; support for and access to short-term intervention in primary care settings; and greater recognition and promotion of mental health issues in common developmental settings and other influential systems. Integral to this approach is the need to implement these components simultaneously and to incorporate family-focused, culturally competent, evidence-based, and developmentally appropriate services. This comprehensive, simultaneous, and integrated approach is needed to achieve real progress in children's mental health in this country. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

新型PT IGBT型开关管与MOSFET型开关管的性能比较

引言 　　具有MOS电路易于驱动、低导通损耗等特点的IGBT管目前主要应用于高电压、强电流电力电子领域.新型PTIGBT管将开关损耗与导通损耗协调得更加合理,凭其技术优势已经能够占领目前由MOSFET管统治的高频高效电子器件领域.在工作电压高于300V的各类工业场合,使用IGBT管替代MOSFET管作为开关电源驱动器件已经成为一种趋势.……     

Computer vision for interactive computer graphics

Vision can be a powerful interface device for computers because of its potential for sensing body position, head orientation, direction of gaze, pointing commands, and gestures. Such unencumbered interaction can make computers easier to use. We describe vision algorithms for interactive graphics and present vision-controlled graphics applications using these algorithms. Some applications employ an artificial retina chip for image detection or preprocessing