Coldplate of pin fin design makes efficient heat exchanger

Flat, hollow coldplate that permits the flow of coolant liquid removes heat from heat-generating electronic equipment. This coldplate solves usual problems of bulk, weight, and excessive pumping requirements

Ablation debris control by means of closed thick film filtered water immersion

The performance of laser ablation generated debris control by means of open immersion techniques have been shown to be limited by flow surface ripple effects on the beam and the action of ablation plume pressure loss by splashing of the immersion fluid. To eradicate these issues a closed technique has been developed which ensured a controlled geometry for both the optical interfaces of the flowing liquid film. This had the action of preventing splashing, ensuring repeatable machining conditions and allowed for control of liquid flow velocity. To investigate the performance benefits of this closed immersion technique bisphenol A polycarbonate samples have been machined using filtered water at a number of flow velocities. The results demonstrate the efficacy of the closed immersion technique: a 93% decrease in debris is produced when machining under closed filtered water immersion; the average debris particle size becomes larger, with an equal proportion of small and medium sized debris being produced when laser machining under closed flowing filtered water immersion; large debris is shown to be displaced further by a given flow velocity than smaller debris, showing that the action of flow turbulence in the duct has more impact on smaller debris. Low flow velocities were found to be less effective at controlling the positional trend of deposition of laser ablation generated debris than high flow velocities; but, use of excessive flow velocities resulted in turbulence motivated deposition. This work is of interest to the laser micromachining community and may aide in the manufacture of 2.5D laser etched patterns covering large area wafers and could be applied to a range of wavelengths and laser types

Two-divisibility of the coefficients of certain weakly holomorphic modular forms

We study a canonical basis for spaces of weakly holomorphic modular forms of weights 12, 16, 18, 20, 22, and 26 on the full modular group. We prove a relation between the Fourier coefficients of modular forms in this canonical basis and a generalized Ramanujan tau-function, and use this to prove that these Fourier coefficients are often highly divisible by 2.Comment: Corrected typos. To appear in the Ramanujan Journa

A note on communicating environmental change for non-market valuation

Communicating change in environmental condition is a critical component of non-market valuation studies. However, the underlying assumptions and implications associated with alternative ways of expressing change in environmental condition for surveys are rarely discussed in the literature. Our review found no cases where alternative formulations were both discussed and tested. In this note we report on our multi-disciplinary analysis of how best to express such change. We interrogate the meaning of, and inferences from, four formulations for quantitative expressions, or metrics, of environmental indicators that are used in the field of ecology and we then evaluate their usefulness in non-market valuation. The assumptions and limitations of each formulation are discussed using seven hypothetical cases of change in environmental condition. We show that formulations for expressing change can be grouped based on two inherent philosophies potentially held by people when they consider their preferences for environmental changes: ‘more is better philosophy’ and ‘restoration philosophy’. We contend that, without careful consideration of which philosophy people may apply, it is possible to inadvertently bias respondent choices when a particular formulation is used in a valuation study. If this happens, resulting value estimates will be a poor reflection of what researchers seek. An alternative approach that does not presuppose a philosophy but instead helps reveal a respondent’s philosophy, is proposed

Genomic and bioinformatics analysis of human adenovirus type 37: New insights into corneal tropism

<p>Abstract</p> <p>Background</p> <p>Human adenovirus type 37 (HAdV-37) is a major etiologic agent of epidemic keratoconjunctivitis, a common and severe eye infection associated with long-term visual morbidity due to persistent corneal inflammation. While HAdV-37 has been known for over 20 years as an important cause, the complete genome sequence of this serotype has yet to be reported. A detailed bioinformatics analysis of the genome sequence of HAdV-37 is extremely important to understanding its unique pathogenicity in the eye.</p> <p>Results</p> <p>We sequenced and annotated the complete genome of HAdV-37, and performed genomic and bioinformatics comparisons with other HAdVs to identify differences that might underlie the unique corneal tropism of HAdV-37. Global pairwise genome alignment with HAdV-9, a human species D adenovirus not associated with corneal infection, revealed areas of non-conserved sequence principally in genes for the virus fiber (site of host cell binding), penton (host cell internalization signal), hexon (principal viral capsid structural protein), and E3 (site of several genes that mediate evasion of the host immune system). Phylogenetic analysis revealed close similarities between predicted proteins from HAdV-37 of species D and HAdVs from species B and E. However, virtual 2D gel analyses of predicted viral proteins uncovered unexpected differences in pI and/or size of specific proteins thought to be highly similar by phylogenetics.</p> <p>Conclusion</p> <p>This genomic and bioinformatics analysis of the HAdV-37 genome provides a valuable tool for understanding the corneal tropism of this clinically important virus. Although disparities between HAdV-37 and other HAdV within species D in genes encoding structural and host receptor-binding proteins were to some extent expected, differences in the E3 region suggest as yet unknown roles for this area of the genome. The whole genome comparisons and virtual 2D gel analyses reported herein suggest potent areas for future studies.</p

The Early Stages of Pedaliodes poesia (Hewitson, 1862) in Eastern Ecuador (Lepidoptera: Satyrinae: Pronophilina)

We describe the immature stages Pedaliodes poesia Hewitson, 1862 from northeastern Ecuador. Chusquea scandens (Poaceae, Bambusoidea) is the larval food plant. Eggs are laid singly or in pairs on the bottom side of host plant leaves. The duration of the egg, larval, and pupal stages, combined, is 99–107 days