Wormhole formation in dissolving fractures

We investigate the dissolution of artificial fractures with three-dimensional, pore-scale numerical simulations. The fluid velocity in the fracture space was determined from a lattice-Boltzmann method, and a stochastic solver was used for the transport of dissolved species. Numerical simulations were used to study conditions under which long conduits (wormholes) form in an initially rough but spatially homogeneous fracture. The effects of flow rate, mineral dissolution rate and geometrical properties of the fracture were investigated, and the optimal conditions for wormhole formation determined.Comment: to be published in J. Geophys Re

Making cheaper labor: Domestic outsourcing and development in the Galilee

Middle Eastern Studie

Elevated growth differentiation factor 15 expression in patients with congenital dyserythropoietic anemia type I

Congenital dyserythropoietic anemia (CDA) is a rare group of red blood cell disorders characterized by ineffective erythropoiesis and increased iron absorption. To determine whether growth differentation factor 15 (GDF15) hyper-expression is associated with the ineffective erythropoiesis and iron-loading complications of CDA type I (CDA I), GDF15 levels and other markers of erythropoiesis and iron overload were studied in blood from 17 CDA I patients. Significantly higher levels of GDF15 were detected among the CDA I patients (10 239 ± 3049 pg/mL) compared with healthy volunteers (269 ± 238 pg/mL). In addition, GDF15 correlated significantly with several erythropoietic and iron parameters including Hepcidin-25, Ferritin, and Hepcidin-25/Ferritin ratios. These novel results suggest that CDA I patients express very high levels of serum GDF15, and that GDF15 contributes to the inappropriate suppression of hepcidin with subsequent secondary hemochromatosis

Complement Factor H Gene Mutation Associated with Autosomal Recessive Atypical Hemolytic Uremic Syndrome

SummaryAtypical hemolytic uremic syndrome (HUS) presents with the clinical features of hypertension, microangiopathic hemolytic anemia, and acute renal failure. Both dominant and recessive modes of inheritance have been reported. This study describes the genetic and functional analysis of a large Bedouin kindred with autosomal recessive HUS. The kindred consists of several related nuclear families in which all parent unions of affected children are consanguineous. A previous report demonstrated that a dominant form of HUS maps to chromosome 1q and that complement factor H (CFH), a regulatory component of the complement system, lies within the region and is involved in the dominant disorder. Early-onset and persistent hypocomplementemia in this Bedouin kindred prompted us to evaluate the CFH gene. Linkage analysis was performed, demonstrating linkage between the disorder and the markers near the CFH gene. Mutation analysis of the CFH coding region revealed a single missense mutation. Functional analyses demonstrate that the mutant CFH is properly expressed and synthesized but that it is not transported normally from the cell. This is the first study reporting that a recessive, atypical, early-onset, and relapsing HUS is associated with the CFH protein and that a CFH mutation affects intracellular trafficking and secretion

Exploring the role of locomotor sensitization in the circadian food entrainment pathway

<div><p>Food entrainment is the internal mechanism whereby the phase and period of circadian clock genes comes under the control of daily scheduled food availability. Food entrainment allows the body to efficiently realign the internal timing of behavioral and physiological functions such that they anticipate food intake. Food entrainment can occur with or without caloric restriction, as seen with daily schedules of restricted feeding (RF) or restricted treat (RT) that restrict food or treat intake to a single feeding time. However, the extent of clock gene control is more pronounced with caloric restriction, highlighting the role of energy balance in regulating clock genes. Recent studies have implicated dopamine (DA) to be involved in food entrainment and caloric restriction is known to affect dopaminergic pathways to enhance locomotor activity. Since food entrainment results in the development of a distinct behavioral component, called food anticipatory activity (FAA), we examined the role of locomotor sensitization (LS) in food entrainment by 1) observing whether amphetamine (AMPH) sensitization results in enhanced locomotor output of FAA and 2) measuring LS of circadian and non-circadian feeding paradigms to an acute injection of AMPH (AMPH cross-sensitization). Unexpectedly, AMPH sensitization did not show enhancement of FAA. On the contrary, LS did develop with sufficient exposure to RF. LS was present after 2 weeks of RF, but not after 1, 3 or 7 days into RF. When food was returned and rats regain their original body weight at 10–15 days post-RF, LS remained present. LS did not develop to RT, nor to feedings of a non-circadian schedule, e.g. variable restricted feeding (VRF) or variable RT (VRT). Further, when RF was timed to the dark period, LS was observed only when tested at night; RF timed to the light period resulted in LS that was present during day and night. Taken together our results show that LS develops with food entrainment to RF, an effect that is dependent on the chronicity and circadian phase of RF but independent of body weight. Given that LS involves reorganization of DA-regulated motor circuitry, our work provides indirect support for the role of DA in the food entrainment pathway of RF. The findings also suggest differences in neuronal pathways involved in LS from AMPH sensitization and LS from RF.</p></div