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The presence of excessive mirror overflow in children with Attention Deficit/Hyperactivity Disorder (ADHD) is discussed in numerous published reports. These reports, however, include a limited age range in their samples. The objective of this study is to examine the effects of diagnosis and sex on mirror overflow and standard deviation (SD) of tap time in children with and without ADHD across a larger age range (5–12 years) of children.
One-hundred and forty-eight children with ADHD and 112 age- and sex-matched typically developing (TD) children completed a finger sequencing task. Mirror overflow, SD of tap time, and mean tap time were measured using finger twitch transducers.
Results reveal a significant diagnostic effect on mirror overflow such that boys and girls with ADHD demonstrate increased overflow compared to same-sex TD children. Boys with ADHD demonstrated more variable tap times compared to TD boys; no diagnostic effect was observed in the girls.
Boys with ADHD exhibit anomalous motor variability; girls with ADHD show similar levels of variability as TD girls. Boys and girls with ADHD exhibit similar levels of excessive mirror overflow. This lack of sex differences on mirror overflow is distinct from reports finding sex effects on overflow and could result from an examination of a broader age range than is included in prior reports. Adolescent data would provide a greater understanding of the trajectory of anomalous mirror overflow across development. Examination of functional and structural connectivity would expand the current understanding of the neurobiological foundation of motor overflow.
Suicide is a global issue among the elderly, but few studies have explored the experiences of suicide ideation in older Asian psychiatric outpatients.
The purposes of this study were to explore triggers of suicide ideation among older first onset cases in psychiatric outpatients in Taiwan and their reasons for not executing suicide.
Older psychiatric outpatients (N=24) were recruited by convenience from one medical centre and one regional hospital in northern Taiwan. Data were collected in individual interviews using a semi-structured guide and analysed by content analysis.
Suicide ideation was triggered by illness and physical discomfort, conflicts with family members/friends, illness of family members, death of family members/friends, and loneliness. Participants’ reasons for not executing suicide were family members’ and friends’ support, receiving treatment, finding a way to shift their attention, fear of increasing pressure on one’s children, religious beliefs, and not knowing how to execute suicide.
Understanding these identified triggers of suicide ideation may help psychiatrists open a channel for conversation with their elderly clients and more readily make their diagnosis. Understanding these identified protective factors against executing suicide can help psychiatrists not only treat depression, but also enhance protective factors for their clients.
Older adults with depression resist accepting depression screening and seeking treatment due to stigmatization of mental disorders and little knowledge about depression. This study was undertaken to develop and determine the psychometrics of an instrument for assessing triggers of suicidal ideation among older outpatients.
Participants were recruited from older outpatients of two hospitals in northern Taiwan. An initial 32-item Triggers of Suicidal Ideation Inventory (TSII) was developed, and its items were validated by experts in two runs of Delphi technique survey. After this TSII was pre-tested in 200 elderly outpatients, 12 items were retained. The 12-item TSII was examined by criterion validity, construct validity, internal consistency reliability, and test-retest reliability.
TSII scores were significantly and positively correlated with the Beck Scale for Suicide Ideation (r = 0.45, P < 0.01), and UCLA Loneliness scores (r = 0.55, P < 0.01), indicating satisfied criterion validity. Participants with depressive tendency tended to have higher TSII scores than participants with no depressive tendency (t = 8.62, P < 0.01), indicating good construct validity. Cronbach's α and the intraclass correlation coefficient for the TSII were 0.70 and 0.99 respectively, indicating acceptable internal consistency reliability and excellent test-retest reliability. Receiver operating characteristic analysis revealed that the area under the curve was 0.83, indicating excellent ability to detect triggers of suicidal ideation. With a cutoff point of 2, the sensitivity and specify were 0.86 and 0.67, respectively.
The TSII can be completed in 5 minutes and is perceived as easy to complete. Moreover, the inventory yielded highly acceptable parameters of validity and reliability.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Fragile X mental retardation 1 (FMR1) full-mutation expansion causes fragile X syndrome. Trans-generational fragile X syndrome transmission can be avoided by preimplantation genetic diagnosis (PGD). We describe a robust PGD strategy that can be applied to virtually any couple at risk of transmitting fragile X syndrome. This novel strategy utilises whole-genome amplification, followed by triplet-primed polymerase chain reaction (TP-PCR) for robust detection of expanded FMR1 alleles, in parallel with linked multi-marker haplotype analysis of 13 highly polymorphic microsatellite markers located within 1 Mb of the FMR1 CGG repeat, and the AMELX/Y dimorphism for gender identification. The assay was optimised and validated on single lymphoblasts isolated from fragile X reference cell lines, and applied to a simulated PGD case and a clinical in vitro fertilisation (IVF)-PGD case. In the simulated PGD case, definitive diagnosis of the expected results was achieved for all ‘embryos’. In the clinical IVF-PGD case, delivery of a healthy baby girl was achieved after transfer of an expansion-negative blastocyst. FMR1 TP-PCR reliably detects presence of expansion mutations and obviates reliance on informative normal alleles for determining expansion status in female embryos. Together with multi-marker haplotyping and gender determination, misdiagnosis and diagnostic ambiguity due to allele dropout is minimised, and couple-specific assay customisation can be avoided.
Nosemosis is a disease of adult honey bees, Apis mellifera Linnaeus (Hymenoptera: Apidae), caused by two described species of Microsporidia: Nosema ceranae Fries and Nosema apis Zander. The epidemiology of N. apis is well understood; however, little is known about N. ceranae in Canadian apiaries. The following study aimed to determine the seasonal patterns of N. ceranae and N. apis in European honey bees in a Québec, Canada, apiary. Honey bees from six hives were sampled from 2008 to 2010 and the amount of spores quantified by both microscopic spore counts and duplex quantitative polymerase chain reaction (qPCR). Results demonstrated that duplex qPCR was the most sensitive technique and was able to detect N. ceranae in samples confirmed negative for microscopic spore counts and conventional polymerase chain reaction (PCR) detection. Results show that N. ceranae is the more prevalent parasite and was present in 75% of collections as single or mixed infections in the sampled apiary. The prevalence of N. apis was lower representing 29.7% throughout the 3 years of the study, and by 2010 was present only as mixed infections. Seasonal patterns of N. apis were consistent with previously published data with peaks in spring and autumn months, while N. ceranae peak infections varied throughout the 3-year study.
Measurements are presented of the magnetoelectric (ME) coupling of nontoxic lead-free multiferroic composites 0.4CoFe2O4-0.6[0.948(K0.5Na0.5)NbO3-0.052LiSbO3]. The composites are found to exhibit an interesting dielectric response under a dc magnetic bias field. The positive magnetodielectric behavior and its strong frequency dependence in the composite could be related to magnetoresistance and the Maxwell-Wagner effect. The ME effects are strongly dependent on the driving field frequency and dc magnetic bias field. The frequency and magnetic field dependence of direct and converse ME coefficients are related to the relative dielectric constant and the variation in the piezomagnetic coupling with magnetic field, respectively. In addition, the dependence of direct and converse ME coefficients on frequency and magnetic field is quite similar in this multiferroic particulate composite.
Under field conditions, the cabbage butterfly, Pieris melete, displays a pupal summer diapause in response to relatively low daily temperatures and gradually increasing day-length during spring and a pupal winter diapause in response to the progressively shorter day-length. To determine whether photoperiod is ‘more’ important than temperature in the determination of summer and winter diapause, or vice versa, the effects of naturally changing day-length and temperature on the initiation of summer and winter diapause were systematically investigated under field conditions for five successive years. Field results showed that the incidence of summer diapause significantly declined with the naturally increasing temperature in spring and summer generations. Path coefficient analysis showed that the effect of temperature was much greater than photoperiod in the determination of summer diapause. In autumn, the incidence of diapause was extremely low when larvae developed under gradually shortening day-length and high temperatures. The incidence of winter diapause increased to 60–90% or higher with gradually shortening day-length combined with temperatures between 20.0°C and 22.0°C. Decreasing day-length played a more important role in the determination of winter diapause induction than temperature. The eco-adaptive significance of changing day-length and temperature in the determination of summer and winter diapause was discussed.
The flight distance, flight time and individual flight activities of males and females of Dendroctonus armandi were recorded during 96-h flight trials using a flight mill system. The body weight, glucose, glycogen and lipid content of four treatments (naturally emerged, starved, phloem-fed and water-fed) were compared among pre-flight, post-flight and unflown controls. There was no significant difference between males and females in total flight distance and flight time in a given 24-h period. The flight distance and flight time of females showed a significant linear decline as the tethered flying continued, but the sustained flight ability of females was better than that of males. The females had higher glycogen and lipid content than the males; however, there was no significant difference between both sexes in glucose content. Water-feeding and phloem-feeding had significant effects on longevity, survival days and flight potential of D. armandi, which resulted in longer feeding days, poorer flight potential and lower energy substrate content. Our results demonstrate that flight distances in general do not differ between water-fed and starved individuals, whereas phloem-fed females and males fly better than water-fed and starved individuals.
Egg cells of Torenia fournieri were isolated from embryo sacs 1 day after anthesis using enzymatic digestion or mechanical dissection. About 5% of the egg cells and zygotes (2–3 from 50 ovules) could be mechanically dissected within 2 h. When 0.1% cellulase and 0.1% pectinase were added to the mannitol isolation solution, about 18% of the egg cells (8–10 from 50 ovules) could be isolated within 2 h. The egg cells isolated by mechanical dissection could be used for in vitro fertilization studies without any of the potentially deleterious effects of the enzymes on the plasma membrane of egg cell. The egg cells isolated using enzymatic digestion could be used in the study of the molecular biology of female gamete because more egg cells could be isolated with this technique. Using enzymatic digestion, over 10 zygotes from 50 ovules (over 20%) were isolated from the pollinated ovules. Coupled with our successful isolation of mature sperm cells, the isolation of egg cells of T. fournieri will make in vitro fertilization possible in a dicotyledon plant.
Carbon nanotubes (CNTs) were grown by electroless Ni-P plated on silicon substrate in a microwave heating chemical vapor deposition (CVD) system with methane gas at 700 °C. The CNTs grown on Ni–P catalyst showed random orientation and small diameter around 15–30 nm. Field emission test results indicated that the Ni–P catalyzed-CNTs exhibited excellent field emission properties. The turn-on field was about 0.56 V/μm with an emission current density 10 μA/cm2 and the threshold field was 4.4 V/μm with an emission current density 10 mA/cm2. These excellent field emission properties may be attributed to the random orientation and small diameter of CNTs.
Adaptive gait planning is an important aspect in the development of control systems for multi-legged robots traversing on rough terrain. The problem of adaptive gait generation
can be viewed as one of finding a sequence of suitable foothold on rough terrain so that legged systems maintain static stability and motion continuity. Due to the limit of static stability, deadlock situation may occur in the process of searching for a suitable foothold, if terrain contains a large number of forbidden zones. In this paper, an improved method for adaptive gait planning is presented by active compensation of stability margin, through center of gravity (CG) adjustment in the longitudinal axis and/or body translation in the lateral direction. An algorithm for the proposed method is developed and embedded in a computer program. Simulation results show that the method provides legged machines with a much larger terrain adaptivity and better deadlock-avoidance ability.
The status of the genera Euparagonimus Chen, 1963 and Pagumogonimus Chen, 1963 relative to Paragonimus Braun, 1899 was investigated using DNA sequences from the mitochondrial cytochrome c oxidase subunit I (CO1) gene (partial) and the nuclear ribosomal DNA second internal transcribed spacer (ITS2). In the phylogenetic trees constructed, the genus Pagumogonimus is clearly not monophyletic and therefore not a natural taxon. Indeed, the type species of Pagumogonimus,P. skrjabini from China, is very closely related to Paragonimusmiyazakii from Japan. The status of Euparagonimus is less obvious. Euparagonimus cenocopiosus lies distant from other lungflukes included in the analysis. It can be placed as sister to Paragonimus in some analyses and falls within the genus in others. A recently published morphological study placed E. cenocopiosus within the genus Paragonimus and probably this is where it should remain.
We have recently proposed the ridge and fringe-field multi-domain homeotropic (RFF-MH) mode for improving viewing angles of thin-film-transistor driven liquid crystal display (TFT-LCD) panels (4). We also demonstrated that the RFF-MH structures are suitable for high resolution desk top TFT-LCD panels (5). In this paper we demonstrated that the RFF-MH method is also suitable for the high-end large-area notebook application since it provides wide viewing angles with a high optical transmission. The ridge structure is constructed on top of the indium tin oxide (ITO) layer of the color filter (CF) substrate, and can be fabricated during the color filter process. The cell process of the RFF-MH panel is compatible to the conventional TFT-LCD cell fabrication process. It requires one extra photolithographic step; however no rubbing treatment is required.
The field dependent birefringence and the tilt angle are measured for a series of four electroclinic liquid crystals. The zero-field birefringence decreased significantly and monotonically with the length of the siloxane side chain. For all four samples, the birefringence and the electroclinic tilt angle increased substantially with the application of a field. At 10 V/µm, the electroclinic tilt angle in DSiKN65 and TSiKN105 exceeded 22.5 degrees and the phase retardation due to the change in the birefringence exceeded a quarter wave. In all four liquid crystals, the electroclinic tilt angle and the field-dependent birefringence were shown to be strongly correlated, suggesting a common origin. Moreover, this correlation persists even at high fields where both processes undergo saturation. A simple orientational model, based on a distribution in the molecular optical axis, was developed to explain the large change in birefringence in the substituted compounds as well as the dependence of δn on electric field.
Conventional (polymer/liquid crystal) composite films exhibit the normal mode electro-optical switching, that is, the light scattering-light transmission switching upon electric field OFF-ON states, respectively. The “reverse mode” electro-optical switching, that is, the light transmission-light scattering switching upon electric field OFF-ON states, respectively, has been investigated for a novel type of composite system being composed of a side chain type liquid crystalline polymer(LCP) and low molecular weight liquid crystals(LCs). The polarizing optical microscopic observation and X-ray diffraction study revealed that the two types of smectic-like short range ordering were present in the (LCP/LCs) composite system in a nematic state. It was confirmed from electric capacitance measurements of the homogeneous alignment cell that these phases with different smectic-like short range orderings each exhibited a different value of threshold voltage. Although the homogeneous alignment cell of the (LCP/LCs) composite system was in a light transmitting state in the absence of an electric voltage, the cell turned into a light scattering state upon the application of an electric voltage of 5-15 V for the cell of 14 µm thick (0.4−1.1 MV" m−1). The reversible change from the light scattering state to the transmission state was observed after removing the electric voltage. The light scattering state of the (LCP/LCs) composite system upon the application of electric voltage might be due to the appearance of optically heterogeneous structure induced by the different values of the threshold voltage between the two types of smectic-like phases with different short range orderings. These phases might be in a phase-separated state with an optical dimension (several hundred nm). The reversible “reverse mode” electro-optical switching was realized for the (LCP/LCs) composite system in a nematic state in which the two types of smectic-like short range orderings were separately formed in an optical size level.
Until recently, it was an empirical fact that creation of a chiral liquid crystal phase required enantiomerically enriched molecules. In addition, to date known ferroelectric and antiferroelectric smectics have also been composed of enantiomerically enriched molecules. Herein are described the first examples of the formation of chiral and antiferroelectric supermolecular liquid crystalline structures from achiral molecules. In one case (apparently metastable) the liquid crystal structure is macroscopically chiral, with samples composed of heterochiral macroscopic domains: a liquid conglomerate.
In holographic Bragg gratings formed by anisotropic photopolymerization of free-radical monomers, an electric field is required to switch the grating between a diffracting and a transmitting state. The voltage necessary to turn the grating completely off is defined as the switching voltage. In this work, we report on the gradual increase of this switching voltage with time after initial fabrication. The switching field increases approximately 60% over a seven-day period for a pentaacrylate/E7 material system. Using dielectric measurements, it is observed that the resistance of the cell does not change over time while the capacitance decreases. FT-IR spectroscopy was also used to explore the continued post-polymerization after fabrication of the gratings. Increases in switching field were observed for samples fully illuminated with light as well as those kept in the dark. We speculate that the rise in the switching voltage is caused by post polymerization of residual reactive moieties located near the polymer/nematic droplet interface. An increase in the amount of interfacial area generated by post-polymerization yields more surface area for the LC molecules to bind; thus a larger field is needed to switch.
Nematic liquid crystal filled with Aerosil particles, a prospective composite material for optoelectronic application, has been investigated by static light scattering and Photon Correlation Spectroscopy (PCS). The Aerosil particles in filled nematic liquid crystals (FN) form a network structure with LC domains about 2500 Å in size with a random distribution of the director orientation of each domain.
We found that the properties of 5CB are considerably affected by the network. The N-I phase transition in filled 5CB was found to be smeared out and depressed. PCS experiments show that two new relaxation processes appear in filled 5CB in addition to the director fluctuation process in bulk. The slow relaxation process, with a broad spectrum of relaxation times, is somewhat similar to the slow decay, which is observed in confined nematic liquid crystal.
The middle frequency process was assigned to the director fluctuations in the surface layer formed at the particle-LC interface. The decay function describing this relaxation process is a stretched exponential (β ≍ 0.7). The temperature dependence of the relaxation times of the middle frequency obeys the Vogel-Rilcher law. Such a temperature dependence, accompanied by a broad spectrum of relaxation times suggests that the dynamics of the director fluctuations near the Aerosil particle-LC interface is glass-like.