The Distribution of \u3ci\u3eCorydalus Cornutus\u3c/i\u3e (Linnaeus) and \u3ci\u3eNigronia Serricornis (Say) (Megaloptera: Corydalidae) in Michigan

(excerpt) The distribution of the hellgrammite [Corydalus cornutus (Linnaeus)] and the sawcombed fishfly [Nigronia serricornis (Say)] in Michigan was determined as part of an investigation of the biology of these large Megalopterans (Knight and Simmons, 1975a, 1975b). Megalopteran larvae are some of the largest aquatic insects, with a maximum length of approximately 84 mm. They are robust larvae with paired lateral abdominal appendages on segments 1-8 and a pair of anal prolegs bearing two strong hooks. They are fiercely predaceous and generally insectivorous, feeding chiefly on larvae of Simulium, Cheumatopsyche, Hydropsyche and Chironomidae, but eating almost anything they can subdue, including their own kind (Chandler, 1956; Stewart et al., 1973)

Bubble-Driven Inertial Micropump

The fundamental action of the bubble-driven inertial micropump is investigated. The pump has no moving parts and consists of a thermal resistor placed asymmetrically within a straight channel connecting two reservoirs. Using numerical simulations, the net flow is studied as a function of channel geometry, resistor location, vapor bubble strength, fluid viscosity, and surface tension. Two major regimes of behavior are identified: axial and non-axial. In the axial regime, the drive bubble either remains inside the channel or continues to grow axially when it reaches the reservoir. In the non-axial regime the bubble grows out of the channel and in all three dimensions while inside the reservoir. The net flow in the axial regime is parabolic with respect to the hydraulic diameter of the channel cross-section but in the non-axial regime it is not. From numerical modeling, it is determined that the net flow is maximal when the axial regime crosses over to the non-axial regime. To elucidate the basic physical principles of the pump, a phenomenological one-dimensional model is developed and solved. A linear array of micropumps has been built using silicon-SU8 fabrication technology, and semi-continuous pumping across a 2 mm-wide channel has been demonstrated experimentally. Measured variation of the net flow with fluid viscosity is in excellent agreement with simulation results.Comment: 18 pages, 18 figures, single colum

Self DNA perpetuates IPF lung fibroblast senescence in a cGAS-dependent manner

Senescence and mitochondrial stress are mutually reinforcing age-related processes that contribute to idiopathic pulmonary fibrosis (IPF); a lethal disease that manifests primarily in the elderly. Whilst evidence is accumulating that GMP-AMP synthase (cGAS) is crucial in perpetuating senescence by binding damaged DNA released into the cytosol, its role in IPF is not known. The present study examines the contributions of cGAS and self DNA to the senescence of lung fibroblasts from IPF patients (IPF-LFs) and age-matched controls (Ctrl-LFs). cGAS immunoreactivity was observed in regions of fibrosis associated with fibroblasts in lung tissue of IPF patients. Pharmacological inhibition of cGAS or its knockdown by silencing RNA (siRNA) diminished the escalation of IPF-LF senescence in culture over 7 days as measured by decreased p21 and p16 expression, histone 2AX? phosphorylation and/or IL-6 production (P < 0.05, n = 5-8). The targeting of cGAS also attenuated etoposide-induced senescence in Ctrl-LFs (P < 0.05, n = 5-8). Levels of mitochondrial DNA (mDNA) detected by qPCR in the cytosol and medium of IPF-LFs or senescence-induced Ctrl-LFs were higher than Ctrl-LFs at baseline (P < 0.05, n = 5-7). The addition of DNAse I (100 U/ml) deaccelerated IPF-LF senescence (P < 0.05, n = 5), whereas ectopic mDNA or the induction of endogenous mDNA release augmented Ctrl-LF senescence in a cGAS-dependent manner (P < 0.05, n = 5). In conclusion, we provide evidence that cGAS reinforces lung fibroblast senescence involving damaged self DNA. The targeting of cGAS to supress senescent-like responses may have potential important therapeutic implications in the treatment of IPF

Spontaneous Stratification in Granular Mixtures

Granular materials size segregate when exposed to external periodic perturbations such as vibrations. Moreover, mixtures of grains of different sizes spontaneously segregate in the absence of external perturbations: when a mixture is simply poured onto a pile, the large grains are more likely to be found near the base, while the small grains are more likely to be near the top. Here, we report a spontaneous phenomenon arising when we pour a mixture between two vertical plates: the mixture spontaneously stratifies into alternating layers of small and large grains whenever the large grains are rougher than the small grains. In contrast, we find only spontaneous segregation when the large grains are more rounded than the small grains. The stratification is related to the occurrence of avalanches; during each avalanche the grains comprising the avalanche spontaneously stratify into a pair of layers through a "kink" mechanism, with the small grains forming a sublayer underneath the layer of large grains.Comment: 4 pages, 6 figures, http://polymer.bu.edu/~hmakse/Home.htm

A cGAS-dependent response links DNA damage and senescence in alveolar epithelial cells:A potential drug target in IPF

Alveolar epithelial cell (AEC) senescence is implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Mitochondrial dysfunction including release of mitochondrial DNA (mtDNA) is a feature of senescence, which led us to investigate the role of the DNA-sensing GMP-AMP synthase (cGAS) in IPF, with a focus on AEC senescence. cGAS expression in fibrotic tissue from lungs of IPF patients was detected within cells immunoreactive for epithelial cell adhesion molecule (EpCAM) and p21, epithelial and senescence markers respectively. Submerged primary cultures of AECs isolated from lung tissue of IPF patients (IPF-AECs, n=5) exhibited higher baseline senescence than AECs from control donors (Ctrl-AECs, n=5-7), as assessed by increased nuclear histone 2AXγ phosphorylation, p21 mRNA and expression of senescence-associated secretory phenotype (SASP) cytokines. Pharmacological cGAS inhibition using RU.521 diminished IPF-AEC senescence in culture and attenuated induction of Ctrl-AEC senescence following etoposide-induced DNA damage. Short interfering RNA (siRNA) knockdown of cGAS also attenuated etoposide-induced senescence of the AEC line, A549. Higher levels of mtDNA were detected in the cytosol and culture supernatants of primary IPF- and etoposide-treated Ctrl-AECs when compared to Ctrl-AECs at baseline. Furthermore, ectopic mtDNA augmented cGAS-dependent senescence of Ctrl-AECs, whereas DNAse I treatment diminished IPF-AEC senescence. This study provides evidence that a self-DNA driven, cGAS-dependent response augments AEC senescence, identifying cGAS as a potential therapeutic target for IPF

Five Lectures On Dissipative Master Equations

1 First Lecture: Basics 1.1 Physical Derivation of the Master Equation 1.2 Some Simple Implications 1.3 Steady State 1.4 Action to the Left 2 Second Lecture: Eigenvalues and Eigenvectors of L 2.1 A Simple Case First 2.2 The General Case 3 Third Lecture: Completeness of the Damping Bases 3.1 Phase Space Functions 3.2 Completeness of the Eigenvectors of L 3.3 Positivity Conservation 3.4 Lindblad Form of Liouville Operators 4 Fourth Lecture: Quantum-Optical Applications 4.1 Periodically Driven Damped Oscillator 4.2 Conditional and Unconditional Evolution 4.3 Physical Signicance of Statistical Operators 5 Fifth Lecture: Statistics of Detected Atoms 5.1 Correlation Functions 5.2 Waiting Time Statistics 5.3 Counting StatisticsComment: 58 pages, 10 figures; book chapter to appear in ``Coherent Evolution in Noisy Environments'', Lecture Notes in Physics, (Springer Verlag, Berlin-Heidelberg-New York). Notes of lectures given in Dresden,23-27 April 200

Transitions in the Horizontal Transport of Vertically Vibrated Granular Layers

Motivated by recent advances in the investigation of fluctuation-driven ratchets and flows in excited granular media, we have carried out experimental and simulational studies to explore the horizontal transport of granular particles in a vertically vibrated system whose base has a sawtooth-shaped profile. The resulting material flow exhibits novel collective behavior, both as a function of the number of layers of particles and the driving frequency; in particular, under certain conditions, increasing the layer thickness leads to a reversal of the current, while the onset of transport as a function of frequency occurs gradually in a manner reminiscent of a phase transition. Our experimental findings are interpreted here with the help of extensive, event driven Molecular Dynamics simulations. In addition to reproducing the experimental results, the simulations revealed that the current may be reversed as a function of the driving frequency as well. We also give details about the simulations so that similar numerical studies can be carried out in a more straightforward manner in the future.Comment: 12 pages, 18 figure

Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.

There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions

Spontaneous emission in a planar Fabry-Perot microcavity

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