To grate a liquid into tiny droplets by its impact on a hydrophobic micro-grid

We report on experiments of drop impacting a hydrophobic micro-grid, of typical spacing a few tens of $\mu$m. Above a threshold in impact speed, liquid emerges to the other side, forming micro-droplets of size about that of the grid holes. We propose a method to produce either a mono-disperse spray or a single tiny droplet of volume as small as a few picoliters corresponding to a volume division of the liquid drop by a factor of up to 10$^5$. We also discuss the discrepancy of the measured thresholds with that predicted by a balance between inertia and capillarity.Comment: 3 pages, 5 figures, Accepted for publication in Applied Physics Letter

Factores de virulencia asociados a especies zoonóticas de Campylobacter spp.

Campylobacter spp., es una bacteria Gram negativa causante de una de las enfermedades transmitida por los alimentos más prevalente en el mundo, la campilobacteriosis. Esta bacteria puede encontrarse en una gran cantidad de animales silvestres y domésticos, así como también en agua, tierra, productos alimenticios pero el más importante reservorio lo constituyen las aves. Campylobacter  spp., es una bacteria patógena que afecta al hombre, causando diarrea y otras enfermedades como septicemia, meningitis o complicaciones, como artritis reactivas y el Síndrome de Guillian-Barré (GBS), aunque se conocen las enfermedades que pueden provocar poco se sabe de los mecanismos de patogenicidad involucrados. Los factores de virulencia que más se han relacionado con patogenicidad son la motilidad por la presencia de flagelos, la capacidad de adherencia e invasión a la célula eucarionte y la producción de citotoxinas. El conocimiento de la naturaleza, de la regulación y de los mecanismos de acción de los factores de virulencia de Campylobacter spp., es indispensable para la prevención y tratamiento de esta enfermedad

Comparing the Canadian and US Systems of Health Care in an Era of Healthcare Reform

This is the published version, made available with the permission of the publisher.The purpose of this article is to provide an informed comparison of health care in the United States and Canada along multiple dimensions, Specifically this article looks at coverage, access, cost, health outcomes, satisfaction, and underlying ideology. Canada fares better than the United States with regard to coverage, cost, and health outcomes. While overall access is better in Canada, patients are sometimes required to endure longer wait times than in the United States. Reports of satisfaction levels vary across studies, but most evidence points toward comparable levels of satisfaction in Canada and the United States. Strong ideological differences underlie the Canadian and American systems, making the acceptance and implementation of certain reforms difficult. The potential impact of the US Patient Protection and Affordable Care Act (PPACA), as well as recent Canadian health care reforms on coverage, access, cost, and health outcomes are also discussed

Alien Registration- Lapierre, Emma A. (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/21836/thumbnail.jp

HIV Tat and Morphine-induced Neurodegeneration in a Beclin 1 Hemizygous Mouse Model

Early in infection, HIV crosses the blood-brain barrier and induces neuropathology. Viral presence in the CNS coupled with secretion of neurotoxic proteins causes neuroinflammation, glial dysfunction, excitotoxicity, and neuronal death. Despite advances in combined antiretroviral therapy, HIV-infected patients present with a spectrum of cognitive and psychomotor deficits collectively referred to as HIV-associated neurological disorders (HAND). A subset of HAND patients abuses drugs such as opiates like heroin and morphine show an exacerbation and rapid progression of HIV neuropathology; however, the mechanisms of this synergy are not well understood. Autophagy is a lysosomal degradative process which eliminates and recycles cytosolic components and is implicated in facilitating HIV-1 replication in the CNS and periphery, and in Tat-induced neurodegeneration. When a key initiator of autophagy Beclin 1 was silenced using siRNAs, there was a marked reduction of HIV-1 replication in human microglia and astrocytes and the corresponding inflammatory response. As such, the goal of the current study is to determine if diminished Beclin 1 is neuroprotective against Tat and morphine-induced neurodegeneration using heterozygous Beclin 1 (Becn1+/-) mice. Examination of Tat and morphine-induced inflammatory molecule secretion revealed that Becn1+/- mixed astrocyte and microglia (glia) exhibited attenuated secretion of cytokine IL-6 and chemokines RANTES and MCP-1 compared to control (C57BL/6J) glia, an effect mediated through the μ-opioid receptor. Dysregulation of autophagy-related gene expression and excessive intracellular calcium accumulation were limited in Becn1+/- glia. When determining the effects of Tat-and morphine co-exposure on neuronal survival in vitro, we found Becn1+/- neurons were particularly sensitive to injury, excitotoxicity, and toxic exposures; however, when C57BL/6J neurons were exposed to conditioned media of C57BL/6J and Becn1+/- glia treated with Tat and morphine, neurons treated with Becn1+/- supernatant had better outcomes than those treated with C57BL/6J conditioned media. Furthermore, despite minimal difference between strains in locomotor assessment, we observed significantly greater striatal neuron losses in adult C57BL/6J mice exposed to intrastriatal Tat-and systemic morphine compared to Becn1+/- mice. Our studies demonstrate the potential of targeting Beclin 1 in glia for the prevention of Tat and opiate-induced CNS dysfunction

Alien Registration- Lapierre, Zephirin Joseph A. (Brunswick, Cumberland County)

https://digitalmaine.com/alien_docs/31518/thumbnail.jp

Alien Registration- Marchand, Ernestine A. (Biddeford, York County)

https://digitalmaine.com/alien_docs/4590/thumbnail.jp

Limit on the Temporal Variation of the Fine-Structure Constant Using Atomic Dysprosium

Over a period of eight months, we have monitored transition frequencies between nearly degenerate, opposite-parity levels in two isotopes of atomic dysprosium (Dy). These transition frequencies are highly sensitive to temporal variation of the fine-structure constant ($\alpha$) due to relativistic corrections of large and opposite sign for the opposite-parity levels. In this unique system, in contrast to atomic-clock comparisons, the difference of the electronic energies of the opposite-parity levels can be monitored directly utilizing a radio-frequency (rf) electric-dipole transition between them. Our measurements show that the frequency variation of the 3.1-MHz transition in $^{163}$Dy and the 235-MHz transition in $^{162}$Dy are 9.0$\pm$6.7 Hz/yr and -0.6$\pm$6.5 Hz/yr, respectively. These results provide a value for the rate of fractional variation of $\alpha$ of $(-2.7\pm2.6)\times 10^{-15}$ yr$^{-1}$ (1 $\sigma$) without any assumptions on the constancy of other fundamental constants, indicating absence of significant variation at the present level of sensitivity.Comment: 4 pages, 2 figure

A Calibrated Time Domain Envelope Measurement System for the Behavioral Modeling of Power Amplifiers

This paper presents a set-up which enables the generation and the calibrated time domain measurements of complex envelopes of modulated signals at both ports of non linear microwave power amplifiers. The architecture of the characterization tool is given. Examples of error corrected time domain envelopes at the input / output RF ports of a 36 dBm output power – 30dB power gain L-band SSPA are shown. Futhermore, the use of this characterization tool and a suitable processing of measurement data are applied to a novel measurement based behavioral modeling approach of non linear devices accounting for memory effects