In memoriam: Kuan-Teh Jeang, MD PhD (1958–2013)

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Meiotic DSB patterning: A multifaceted process

Meiosis is a specialized two-step cell division responsible for genome haploidization and the generation of genetic diversity during gametogenesis. An integral and distinctive feature of the meiotic program is the evolutionarily conserved initiation of homologous recombination (HR) by the developmentally programmed induction of DNA double-strand breaks (DSBs). The inherently dangerous but essential act of DSB formation is subject to multiple forms of stringent and self-corrective regulation that collectively ensure fruitful and appropriate levels of genetic exchange without risk to cellular survival. Within this article we focus upon an emerging element of this control—spatial regulation—detailing recent advances made in understanding how DSBs are evenly distributed across the genome, and present a unified view of the underlying patterning mechanisms employed

Not in education, employment and training: pathways from toddler difficult temperament

Background: Youths disengaged from the education system and labour force (i.e. ‘Not in Education, Employment, or Training’ or ‘NEET’) are often at reduced capacity to flourish and thrive as adults. Developmental precursors to NEET status may extend back to temperamental features, though this – and possible mediators of such associations such as attention deficit hyperactivity (ADHD) symptoms and antisocial behaviours (ASB) – have yet to be directly tested. This study investigates if i) difficult temperament in toddlerhood associates with NEET status in adulthood and ii) different subdomains of ADHD (i.e. hyperactivity-impulsivity vs. inattention) in late childhood and ASB in adolescence partially explain this pathway. Methods: Participants were 6,240 mother-child dyads (60.7% female) from the Avon Longitudinal Study of Parents and Children. Mothers reported on their child’s (a) difficult temperament (i.e. mood, intensity and adaptability) at age 2 and (b) ADHD symptoms at ages 8 and 10. Participants reported their own ASB at age 14 and NEET status in adulthood (ages 18, 20, 22 and 23). Results: First, higher levels of difficult temperament in toddlerhood directly associated with an increased probability of being NEET in adulthood. Second, this effect was carried through hyperactivity-impulsivity, but not inattention, in late childhood, and ASB in adolescence; this demonstrates differential contribution to the pathway between the ADHD dimensions, with symptoms of hyperactivity-impulsivity playing a prominent role. Conclusions: Early difficult temperament is a vulnerability factor for NEET status in adulthood. Our findings suggest that one developmental pathway for this vulnerability manifests through increased hyperactivity-impulsivity in childhood and ASB in adolescence. Of note, difficult temperament, as measured here, reflects difficulties in emotional and behavioural self-control (e.g. low adaptability and high intensity negative emotional expressions). Our results, therefore, suggest a prominent developmental role for lack of self-control from toddlerhood onwards in increasing risk for NEET

Semi-supervised drug-protein interaction prediction from heterogeneous biological spaces

biological space

Developmental pathways from toddler difficult temperament to child generalized psychopathology and adult functioning

BACKGROUND: Early difficult temperament and child mental health problems are consistently associated with impaired functioning in adulthood. We examined three potential pathways between difficult temperament in toddlerhood (age 2) and depressive symptoms (ages 21-23) and well-being (age 23): i) direct - early difficult temperament directly associates with these outcomes, ii) mediated - these direct effects are also mediated by a general psychopathology factor in late childhood/early adolescence (GPF; ages 7, 10,and 13), and iii) moderated-mediated - these mediated effects are also moderated by negative (age 42 months) and positive (age 33 months) parenting behaviors. METHODS: The analytic sample included 1892 mother-child dyads (33.4% male children) from the Avon Longitudinal Study of Parents and Children (ALSPAC). Mothers reported on their child's difficult temperament, negative parenting, positive parenting, and child's mental health symptoms. In adulthood, participants reported their own depressive symptoms and well-being (i.e. mental well-being, life satisfaction, happiness). RESULTS: First, early difficult temperament associated directly and positively with depressive symptoms, but negatively with well-being in adulthood. Second, the GPF in late childhood/early adolescence mediated these direct associations. Third, the mediated pathways were not moderated by negative or positive parenting. LIMITATIONS: i) low risk community sample, ii) early risks are based on maternal reports. CONCLUSIONS: Temperament is a risk factor for impaired psychosocial functioning in adulthood, manifested through increased susceptibility to psychopathology in childhood/adolescence. Although more research is needed to test their generalizability, these findings suggest that targeting early difficult temperament may alleviate the risk for later mental health difficulties and may increase general well-being

Hexagonal Boron Nitride-Enhanced Optically Transparent Polymer Dielectric Inks for Printable Electronics.

Solution-processable thin-film dielectrics represent an important material family for large-area, fully-printed electronics. Yet, in recent years, it has seen only limited development, and has mostly remained confined to pure polymers. Although it is possible to achieve excellent printability, these polymers have low (≈2-5) dielectric constants (ε r ). There have been recent attempts to use solution-processed 2D hexagonal boron nitride (h-BN) as an alternative. However, the deposited h-BN flakes create porous thin-films, compromising their mechanical integrity, substrate adhesion, and susceptibility to moisture. These challenges are addressed by developing a "one-pot" formulation of polyurethane (PU)-based inks with h-BN nano-fillers. The approach enables coating of pinhole-free, flexible PU+h-BN dielectric thin-films. The h-BN dispersion concentration is optimized with respect to exfoliation yield, optical transparency, and thin-film uniformity. A maximum ε r ≈ 7.57 is achieved, a two-fold increase over pure PU, with only 0.7 vol% h-BN in the dielectric thin-film. A high optical transparency of ≈78.0% (≈0.65% variation) is measured across a 25 cm2 area for a 10 μm thick dielectric. The dielectric property of the composite is also consistent, with a measured areal capacitance variation of <8% across 64 printed capacitors. The formulation represents an optically transparent, flexible thin-film, with enhanced dielectric constant for printed electronics.EPSRC funding acknowledged (EP/L016087/1

Conductance of graphene nanoribbon junctions and the tight binding model

Planar carbon-based electronic devices, including metal/semiconductor junctions, transistors and interconnects, can now be formed from patterned sheets of graphene. Most simulations of charge transport within graphene-based electronic devices assume an energy band structure based on a nearest-neighbour tight binding analysis. In this paper, the energy band structure and conductance of graphene nanoribbons and metal/semiconductor junctions are obtained using a third nearest-neighbour tight binding analysis in conjunction with an efficient nonequilibrium Green’s function formalism. We find significant differences in both the energy band structure and conductance obtained with the two approximations

Molecular Identification of Spirometra erinaceieuropaei Tapeworm in Cases of Human Sparganosis, Hong Kong

Human sparganosis is a foodborne zoonosis endemic in Asia. We report a series of 9 histologically confirmed human sparganosis cases in Hong Kong, China. All parasites were retrospectively identified as Spirometra erinaceieuropaei. Skin and soft tissue swelling was the most common symptom, followed by central nervous system lesions.published_or_final_versio

102 fs pulse generation from a long-term stable, inkjet-printed black phosphorus-mode-locked fiber laser.

We demonstrate a long-term stable, all-fiber, erbium-doped femtosecond laser mode-locked by a black phosphorus saturable absorber. The saturable absorber, fabricated by scalable and highly controllable inkjet printing technology, exhibits strong nonlinear optical response and is stable for long-term operation against intense irradiation, overcoming a key drawback of this material. The oscillator delivers self-starting, 102 fs stable pulses centered at 1555 nm with 40 nm spectral bandwidth. This represents the shortest pulse duration achieved from black phosphorus in a fiber laser to date. Our results demonstrate the great potential for black phosphorus as an excellent candidate for long-term stable ultrashort pulse generation

Trace elements in road-deposited and waterbed sediments in Kogarah Bay, Sydney: Enrichment, sources and fractionation

© 2015 CSIRO. Trace elements (TEs) in road-deposited sediments (RDS) can be transported by stormwater to neighbouring water bodies to cause aquatic pollution. A study was conducted in Kogarah Bay, Sydney, Australia, to assess the possible sources and potential mobility of TEs in RDS and the contribution to the TE load to the adjacent waterbed sediments in canals and the bay. Of the 11 TEs analysed, pseudo-total concentrations of zinc (Zn), copper (Cu), vanadium (V), chromium (Cr), and antimony (Sb) were greatly enriched in RDS over baseline soils (top 10cm depth) collected in bushlands. All TE concentrations in waterbed sediments (top 10cm depth) were similar to those in baseline soils but lower than in RDS. Correlation and principal component analyses revealed that Zn, Cu, Cr and Sb were related to each other in RDS, and probably originated from tyres and brake linings. Vanadium occurred in another component, likely to have originated mainly from road asphalt. Pseudo-total and mobile-fraction (0.1m acetic acid, pH 2.85 extraction) TE concentrations in RDS were: iron>manganese, Zn>Cu, lead>Cr, nickel, V, Sb, cadmium. The potential ecological TE risk was low to medium in RDS but low in baseline soils and waterbed sediments