Nonaqueous Phase Liquid Pool Dissolution as a Function of Average Pore Water Velocity

Bench-scale reactor experiments were performed to study the dissolution of a binary naphthalene-in-nonane mixture nonaqueous phase liquid (NAPL) pool over a wide range of average pore water velocities, vx (≈0.1–60 m/day). Experimental NAPL pool dissolution flux values were determined using a steady-state mass balance approach. The experimental flux data were compared to model predictions made assuming either local equilibrium or mass-transfer limited conditions. The local equilibrium model could describe the trends in the average effluent concentration and dissolution flux with 0.110?m/day. Data determined to be under mass-transfer limited conditions were fit to the nonequilibrium model to estimate values for an overall mass-transfer coefficient. The calculated overall mass-transfer coefficients had an average value of 0.407 m/day and showed no correlation with vx, probably due to mass-transfer resistance becoming dominated by the diffusional resistance in the NAPL. These results suggest that the nonequilibrium approach is better suited for describing high velocity (vx>10?m/day) dissolution of multicomponent NAPL pools, and that flushing of groundwater at very high velocities may not be an effective approach for enhancing NAPL-pool dissolution flux.     

General relativity and quantum mechanics: towards a generalization of the Lambert W function A Generalization of the Lambert W Function

We present a canonical form for a natural and necessary generalization of the Lambert W function, natural in that it requires minimal mathematical definitions for this generalization, and necessary in that it provides a means of expressing solutions to a number of physical problems of fundamental nature. This generalization expresses the exact solutions for general-relativistic self-gravitating N-body systems in one spatial and one time dimension, and a previously unknown mathematical link between the (1+1) gravity problem and the Schrödinger wave equation.     

Age and ethnicity affect the risk and outcome of focal segmental glomerulosclerosis

In patients with proteinuria, African-American (AA) ethnicity is reported to be a risk factor for focal segmental glomerulosclereosis (FSGS) and its progression to end-stage renal disease (ESRD). We reviewed our single-center experience to determine the probability of FSGS and its progression to ESRD based on ethnicity and age at presentation in children with proteinuria with or without nephrotic syndrome. Proteinuria without systemic disease or acute glomerulonephritis was the presenting feature in 17% (236/1,403) of children in the renal patient database of Texas Children's Hospital, Baylor College of Medicine. Histopathological diagnoses were established in 107 of 236 patients (45%). FSGS was identified in 65 patients, accounting for 28% of all patients with proteinuria and 61% of patients who underwent renal biopsy. FSGS was more prevalent in AA (45%) than in non-AA patients (22%) (P=0.001), and AA patients with FSGS were older at presentation (12.7+/-4.4 years) than non-AA patients (5.6+/-4.6 years) (P<0.001). Among patients who underwent renal biopsy, increasing age at presentation increased the probability of having FSGS in AA but not non-AA patients (P=0.04). Five-year actuarial renal survival of FSGS was worse in AA (8%) than in non-AA patients (31%) (P=0.01). These data suggest an increased risk and worse outcome of FSGS in AA compared with non-AA children.     

Benign paroxysmal tonic upward gaze syndrome

INTRODUCTION: The benign paroxysmal tonic upward gaze syndrome (BPTUG) is a rare condition. We present two new cases analyzing the clinical, genetic, evolution and therapeutic aspects. CLINICAL CASES: Case 1. A 2 year-old girl with no family history of similar disorders started, at the age of 6 months, to have episodes of upward deviation of gaze with hyperextension of the neck and vertical nystagmus of fixation, increased by nervousness and episodes of fever. Some episodes caused the patient to fall in spite of there being no alteration of consciousness. Case 2. From the age of five months a 1 year-old girl with no significant personal or family history had episodes of ocular deviation upwards with forward inclination of the head to correct her gaze and slow motor development from the age of five months. RESULTS: Complementary studies were normal in both patients. As in the cases described in the literature, our cases had no family history and were not sensitive to Dopa. To date 11 children have been described in the literature and few familial cases seen with dominant autosomal inheritance. CONCLUSIONS: Our patients had a non-epileptic paroxystic phenomenon known as BPTUG syndrome. This condition starts during the first year of life, has a benign course and the episodes have ceased by the age of four years. We believe it is important to consider the differential diagnosis with epileptic phenomena, evaluate the response to L-Dopa and bear in mind that this syndrome may be the clinical expression of several different conditions. Although the course is usually benign, it may later be associated with other signs of neurological problems which should be taken into account.     

Cellular mechanisms of intestine regeneration in the sea cucumber, Holothuria glaberrima Selenka (Holothuroidea:Echinodermata)

Echinoderms are the deuterostome group with the most striking capacity to regenerate lost body parts. In particular, members of the class Holothuroidea are able to regenerate most of their internal organs following a typical evisceration process. Such formation of new viscera in an adult organism provides a unique model to study the process of organogenesis. We have studied this process in the sea cucumber Holothuria glabberrima by describing the spatial and temporal pattern of cellular events that occur during intestine regeneration following chemically induced evisceration. Regeneration begins as a thickening of the mesenteries that supported the autotomized organs to the body wall. The mesenterial thickening consists of tissues where most of the cellular populations found in the normal intestine are already present. However, the cell numbers differ, particularly those of hemocytes and amoebocytes, suggesting that some of these cells play an important role in the formation of the solid rod of hypertrophic mesentery that characterizes the intestinal primordia. The appearance of the luminal epithelium, together with the formation of the lumen, occurs during the second week of regeneration by proliferation and extensive migration of cells from the esophagus and cloacal ends into the thickenings. At this stage all tissue layers are present, but it takes an additional week for them to exhibit the proportions typical of the normal organ. Cell division, as determined by BrdU labeling, mainly occurs in the coelomic epithelia of the hypertrophic mesentery and in the regenerating luminal epithelium. Our study provides evidence that the process of new organ formation in holothurians can be described as an intermediate process showing characteristics of both epimorphic and morphallactic phenomena.     

A study on the factors for improving the ethanol production from Jerusalem artichoke by Kluyveromyces fragilis

This study is to investigate the factors influencing the alcohol production byKluyveromyces fragilis using the juice of Jerusalem Artichoke tubers. The cell growth rate and ethanol production rate were stimulated by aeration and by the addition of unsaturated fatty acids and the cell mass production and the ethanol production were substantially improved. It was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of alcohol tolerance of yeast.     

Comparison of molecular changes in lung cancers in HIV-positive and HIV-indeterminate subjects

CONTEXT: Human immunodeficiency virus (HIV) infection has been associated with an increasing incidence of malignancy, and HIV-infected persons have an increased incidence of primary lung carcinoma compared with the general population. OBJECTIVE: To investigate the molecular changes present in HIV-associated lung tumors and compare them with those present in lung carcinomas arising in HIV-indeterminate subjects ("sporadic tumors"). DESIGN: Convenience sample. SUBJECTS: Archival tissues from 11 HIV-positive persons and from 35 persons of indeterminate HIV status. SETTING: University-based medical centers and affiliated hospitals. MAIN OUTCOME MEASURES: Analysis of frequency of loss of heterozygosity (LOH) and microsatellite alteration (MA) using polymerase chain reaction and 16 polymorphic microsatellite markers at 8 chromosomal regions frequently deleted in lung cancer. Presence of HIV and human papillomavirus (HPV) sequences. RESULTS: The overall frequency of LOH at all chromosomal regions tested and the frequencies at most of the individual regions were similar in the 2 groups. Frequency of MA present in the HIV-associated tumors (0.18) was 6-fold higher than in sporadic tumors (0.03) (P<.001). At least 1 MA was present in 10 (91%) of 11 HIV-associated tumors vs 17 (48%) of 35 sporadic tumors (P=.02). Molecular changes were independent of tumor stage and gender. HIV and HPV sequences were not detected in the HIV-associated lung carcinomas. CONCLUSIONS: Microsatellite alterations, which reflect widespread genomic instability, occur at greatly increased frequency in HIV-associated lung carcinomas. Although the mechanism underlying the development of increased MAs is unknown, it may play a crucial role in the development of many HIV-associated tumors.