Identifying a distinctive familial frequency band in reaction time fluctuations in ADHD.

Objective: Patients with ADHD are typically more variable in their reaction times (RT) than control children. Signal processing analyses have shown that time series RT data of children with ADHD have a distinctive low frequency periodic structure suggestive of a pattern of occasional spontaneous performance lapses. Here we use a fine-grained analysis of spectral power across a broader frequency range to differentiate the periodic qualities of ADHD time series RT data from (a) 1/frequency noise, and (b) control performance. We also assess the familiality of these frequencies by using a proband-sibling design. Method: Seventy-one children with ADHD, one of their siblings, and 50 control participants completed a simple RT task. Power across the RT frequency spectrum was calculated. The frequencies significantly differentiating the two groups were identified. Familiality was assessed in two ways: first, by comparing probands with their unaffected siblings and controls, and, second, by investigating the siblings of neuropsychologically impaired and unimpaired children with ADHD. Results: Analyses converged to highlight the potential importance of the .20–.26 Hz band in differentiating the periodic structure of ADHD RT time series data from both 1/frequency noise and control performance. This frequency band also showed the strongest evidence of familiality. Conclusions: RT performance of children with ADHD had a distinctive periodic structure. The band identified as most differentiating and familial was at a higher frequency than in most previous reports. This highlights the importance of employing tasks with faster interstimulus intervals that will allow a larger portion of the frequency spectrum to be examined. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The face in the crowd effect unconfounded: Happy faces, not angry faces, are more efficiently detected in single- and multiple-target visual search tasks.

Is it easier to detect angry or happy facial expressions in crowds of faces? The present studies used several variations of the visual search task to assess whether people selectively attend to expressive faces. Contrary to widely cited studies (e.g., ?hman, Lundqvist, & Esteves, 2001) that suggest angry faces “pop out” of crowds, our review of the literature found inconsistent evidence for the effect and suggested that low-level visual confounds could not be ruled out as the driving force behind the anger superiority effect. We then conducted 7 experiments, carefully designed to eliminate many of the confounding variables present in past demonstrations. These experiments showed no evidence that angry faces popped out of crowds or even that they were efficiently detected. These experiments instead revealed a search asymmetry favoring happy faces. Moreover, in contrast to most previous studies, the happiness superiority effect was shown to be robust even when obvious perceptual confounds—like the contrast of white exposed teeth that are typically displayed in smiling faces—were eliminated in the happy targets. Rather than attribute this effect to the existence of innate happiness detectors, we speculate that the human expression of happiness has evolved to be more visually discriminable because its communicative intent is less ambiguous than other facial expressions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

pH dependent spontaneous growth of ellagic acid assemblies for targeting HeLa cells

Herein, we have studied the self-assembly and the spontaneous growth of microassemblies of the plant polyphenol ellagic acid for HeLa cancer cell imaging and therapy. The growth of the assemblies was studied at varying pH over time. It was found that initially microspheres were formed which gradually transformed into microfibers via nucleation and polymerization process. The optimum growth of microfibers was found to be in the pH range of 6-8. We have shown that the microfibers successfully adhered to the HeLa cell membranes and inhibited their proliferation. This biological approach, using assemblies derived from plant polyphenols, may be used for direct cellular drug delivery and may potentially help develop a simple and economical method to create building blocks with desired properties for a new generation of sensors, bioimaging and drug delivery systems.     

Fashion retailing – past,present and future

This issue of Textile Progress reviews the way that fashion retailing has developed as a result of the application of the World Wide Web and information and communications technology (ICT) by fashion-retail companies. The review therefore first considers how fashion retailing has evolved, analysing retail formats, global strategies, emerging and developing economies, and the factors that are threatening and driving growth in the fashion-retail market. The second part of the review considers the emergence of omni-channel retailing, analysing how retail has progressed and developed since the adoption of the Internet and how ICT initiatives such as mobile commerce (m-commerce), digital visualisation online, and in-store and self-service technologies have been proven to support the progression and expansion of fashion retailing. The paper concludes with recommendations on future research opportunities for gaining a better understanding of the impacts of ICT and omni-channel retailing, through which it may be possible to increase and develop knowledge and understanding of the way the sector is developing and provide fresh impetus to an already-innovative and competitive industry.     

Ring-Sheared Drop (RSD): Microgravity Module for Containerless Flow Studies

Microgravity is potentially a powerful tool for investigating processes that are sensitive to the presence of solid walls, since fluid containment can be achieved by surface tension. One such process is the transformation of protein in solution into amyloid fibrils; these are protein aggregates associated with neurodegenerative diseases such as Alzheimer’s and Parkinson’s. In addition to solid walls, experiments with gravity are also subject to influences from sedimentation of aggregates and buoyancy-driven convection. The ring-sheared drop (RSD) module is a flow apparatus currently under development to study formation of amyloid fibrils aboard the International Space Station (ISS). A 25 mm diameter drop of protein solution will be contained by surface tension and constrained by a pair of sharp-edged tubes, forming two contact rings. Shear can be imparted by rotating one ring with the other ring kept stationary. Here we report on parabolic flights conducted to test the growth and pinning of 10 mm diameter drops of water in under 10 s of microgravity. Finite element method (FEM) based fluid dynamics computations using a commercial package (COMSOL) assisted in the design of the parabolic flight experiments. Prior to the parabolic flights, the code was validated against experiments in the lab (1 g), on the growth of sessile and pendant droplets. The simulations show good agreement with the experiments. This modeling capability will enable the development of the RSD at the 25 mm scale for the ISS.     

Biopolymers for Antitumor Implantable Drug Delivery Systems: Recent Advances and Future Outlook

In spite of remarkable improvements in cancer treatments and survivorship, cancer still remains as one of the major causes of death worldwide. Although current standards of care provide encouraging results, they still cause severe systemic toxicity and also fail in preventing recurrence of the disease. In order to address these issues, biomaterial‐based implantable drug delivery systems (DDSs) have emerged as promising therapeutic platforms, which allow local administration of drugs directly to the tumor site. Owing to the unique properties of biopolymers, they have been used in a variety of ways to institute biodegradable implantable DDSs that exert precise spatiotemporal control over the release of therapeutic drug. Here, the most recent advances in biopolymer‐based DDSs for suppressing tumor growth and preventing tumor recurrence are reviewed. Novel emerging biopolymers as well as cutting‐edge polymeric microdevices deployed as implantable antitumor DDSs are discussed. Finally, a review of a new therapeutic modality within the field, which is based on implantable biopolymeric DDSs, is given.     

一餐五常米,浑忘酒肉香

正遥远的塞外北国,神秘的白山黑水,在此灵动的黑土地上孕育着传奇稻谷——五常大米,它清淡略甜,绵软略粘,芳香爽口的性格深受人们喜爱,所谓一餐五常米,浑忘酒肉香。本刊专访南京大米科技总经理朱创新,跟随他一睹那好山、好水、好米。好山好水孕好米乾隆年间,民谚流传:五常米,帝王粮。上有所好,下必甚焉。清皇室的喜爱,使得京城富户都以吃到五常大米为荣。     

Blood flow through the embryonic heart outflow tract during cardiac looping in HH13–HH18 chicken embryos

Blood flow is inherently linked to embryonic cardiac development, as haemodynamic forces exerted by flow stimulate mechanotransduction mechanisms that modulate cardiac growth and remodelling. This study evaluated blood flow in the embryonic heart outflow tract (OFT) during normal development at each stage between HH13 and HH18 in chicken embryos, in order to characterize changes in haemodynamic conditions during critical cardiac looping transformations. Two-dimensional optical coherence tomography was used to simultaneously acquire both structural and Doppler flow images, in order to extract blood flow velocity and structural information and estimate haemodynamic measures. From HH13 to HH18, peak blood flow rate increased by 2.4-fold and stroke volume increased by 2.1-fold. Wall shear rate (WSR) and lumen diameter data suggest that changes in blood flow during HH13–HH18 may induce a shear-mediated vasodilation response in the OFT. Embryo-specific four-dimensional computational fluid dynamics modelling at HH13 and HH18 complemented experimental observations and indicated heterogeneous WSR distributions over the OFT. Characterizing changes in haemodynamics during cardiac looping will help us better understand the way normal blood flow impacts proper cardiac development.     

Physical activity and energy expenditure in undernutrition

The most accurate measurement of energy expenditure (EE) in free-living individual subjects is by the doubly-labelled water technique. The minute-by-minute heart rate (fH) method, while not yet suitable for individuals, will give excellent measurements of EE in small groups of subjects as well as the pattern of EE while wearing the fH recorder. In adults, the few studies available indicate that chronic energy deficiency (CED) results in decreased energy expenditure. In pre-school children, CED results in decreased activity as a first line of defense against decreased rate of growth. In marginally malnourished school children, the lower levels of EE are the results of their smaller size. However, they are unable to cope with situations of increased activity above ordinary levels. The relative effort exerted by control and undernourished boys and girls 6-16 y of age averaged approximately 25% VO2 max during 12 h of school days. There was a -3% change with age but there were no sex or nutritional status effects on average % VO2 max. It is suggested that this relative constancy in % VO2max in such disparate groups may be indicative of some physiological regulation of activity levels.     

Twelve-month follow-up of virtual reality and standard exposure therapies for the fear of flying.

This study reports the 12-mo follow-up from patients with the fear of flying who were treated in a controlled study and randomly assigned (n=49) to virtual reality exposure (VRE) therapy, standard exposure (SE) therapy, or to a wait-list control (WL). VRE and SE were equally superior to WL. At 12 mo posttreatment, data were gathered on 24 of the 30 (80%) patients who were assigned to VRE or SE. Patients maintained their treatment gains, and 92% of VRE participants and 91% of SE participants had flown on a real airplane since the graduation flight. This is the 1st year-long follow-up of patients having been treated with VRE and indicates that short-term treatment can have lasting effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)