Kinetics of heavy metal vaporization from model wastes in a fluidized bed

Metal vaporization experiments were carried out in an atmospheric fluidized bed to study the influence of operating conditions on the extent of heavy metal (HM) release in fumes from municipal solid waste incinerators. Modelwastes spiked with compounds of Pb, Cd, and Zn were used. The parameters studied were temperature, treatment duration, matrix of the model waste (mineral and organic), HM initial speciation, and gas composition (N2, air, air + HCl, gas mixture simulating the incinerators). The extent of vaporization was measured by solid sample analysis and on-line analysis of the gaseous effluent, after customization of the ICP technique for gas analysis. The results indicate the metal vaporization rate is very high initially and then slows. The results with mineral matrices give the decreasing order of volatility Cd > Pb > Zn, but in industrial incinerators Zn volatilizes slightly more than Pb. Temperature (especially for porous alumina) and mineral matrix have a strong influence on the HM vaporization, but HCl concentration and HM initial speciation do not. The gas composition and the initial metal concentration are significant parameters. The matrix influence clearly denoted the mass transfer limitations in the vaporization process from mineral matrix.     

Clinical and Molecular Characterization of Patients with Mucopolysaccharidosis Type I in an Algerian Series

Mucopolysaccharidoses (MPS’s) represent a subgroup of lysosomal storage diseases related to a deficiency of enzymes that catalyze glycosaminoglycans degradation. Mucopolysaccharidosis type I (MPS I) is a rare autosomal recessive disorder caused by a deficiency of α-l-iduronidase encoded by the IDUA gene. Partially degraded heparan sulfate and dermatan sulfate accumulate progressively and lead to multiorgan dysfunction and damage. The aim of this study is to describe the clinical, biochemical, and molecular characteristics of 13 Algerian patients from 11 distinct families. MPS I diagnosis was confirmed by molecular study of the patients’ IDUA gene. Clinical features at the diagnosis and during the follow-up are reported. Eighty-four percent of the studied patients presented with a mild clinical phenotype. Molecular study of the IDUA gene allowed the characterization of four pathological variations at the homozygous or compound heterozygote status: IDUA NM_00203.4:c.1598C>G-p.(Pro533Arg) in 21/26 alleles, IDUA NM_00203.4:c.532G>A-p.(Glu178Lys) in 2/26 alleles, IDUA NM_00203.4:c.501C>G-p.(Tyr167*) in 2/26 alleles, and IDUA NM_00203. 4: c.1743C>G-p.(Tyr581*) in 1/26 alleles. This molecular study unveils the predominance of p.(Pro533Arg) variation in our MPS I patients. In this series, the occurrence of some clinical features linked to the Scheie syndrome is consistent with the literature, such as systematic valvulopathies, corneal opacity, and umbilical hernia; however, storage signs, facial dysmorphic features, and hepatomegaly were more frequent in our series. Screening measures for these debilitating diseases in highly consanguineous at-risk populations must be considered a priority health problem.     

Magnetic resonance imaging of coronary arteries and coronary stenosis

Coronary artery imaging is an important investigation for the management of coronary artery disease. Alternative noninvasive imaging would be useful, but the small caliber and tortuosity of the coronary vessels and cardiac and respiratory motion create formidable imaging problems. We first studied 21 normal subjects and 5 with coronary artery disease established by X-ray contrast angiography, of whom 2 had undergone bypass grafting. Of these, 22 were imaged successfully. Identification of the artery was possible for the left main stem, left anterior descending, right coronary, and left circumflex arteries respectively in 95%, 91%, 95%, and 76%. The arterial diameter at the origin could be measured in 77%, 77%, 81%, and 63%. The mean ±SD arterial diameter in each case (4.8±0.8, 3.7±0.5, 3.9±0.9, and 2.9±0.6 mm) was not significantly different from reference values (allp=ns). The mean length of artery visualized was 10.4±5.2,46.7±22.8,53.7±27.9, and 26.3±17.5 mm. In 12 normal males, the total coronary area was 30.9±9.2 mm² and the ratio compared with body surface area was 16.4±4.4 mm² m^–2 (bothp=ns compared with reference values). In seven patients, with X-ray contrast coronary angiography, the proximal arterial diameter measured by magnetic resonance was 3.9±1.1 mm, and by X-ray contrast angiography 3.7±1.0 mm (p=ns). We then studied 17 patients with angina. Imaging of just the relevant artery was performed and analysis was blinded to the X-ray angiography results. Stenosis was identified on the magnetic resonance (MR) images by localized reduction in vessel signal intensity. Stenosis location by MR was assessed by measurement of its distance from a reference vessel, with correlation to the X-ray findings. X-ray coronary angiography showed 23 stenoses of which 15 (65%) were correctly located by blind assessment of the MR images. Of the eight remaining stenoses, a further 5 (63%) were correctly located on the MR images after retrospective comparison (overall sensitivity 87%). There were three lesions thought to represent stenosis by MR, which on review of the X-ray angiogram proved to be a minor stenosis <50% (two cases) or a tortuous vessel (one case). Greater signal loss was seen in the more severe stenoses. The stenosis length by MRI was greater than by X-ray (8.4 versus 5.1 mm,p<0.001). The overestimation of stenosis length may be due to turbulence.     

Application of Selected Natural Antimicrobial Formulations for the Control of Food Pathogens in Fresh-Cut Cauliflower

In recent years, research on biopolymer based-coating containing natural antimicrobial agents is developing significantly. The objective of this study was to evaluate the antimicrobial efficiency of six formulations containing pre-selected natural antimicrobial compounds against Listeria monocytogenes, Escherichia coli O 157：H7, Salmonella typhimurium, the total bacteria and total yeasts and molds in cauliflower. Each formulation was subjected to a sensory test in parallel to microbiological analysis and the efficiency during storage at 5 ℃ was evaluated for the two best formulations, based on their ability to eliminate the target microorganisms. Both formulations were able to reduce all pathogens and total flora below detectable levels after 24 h of storage at 5 ℃. Using washing or spraying treatments, the two formulations were able to reduce Listeria to undetectable levels for 3 d. This efficiency was extended to 7 d when the formulations were incorporated into an edible coating. Washing treatment with the two formulations was also able to limit the growth of yeast and molds at levels lower than 2 log, for more than 7 d. The population of E. coli was reduced to below the detection limit during 14 d of storage, after washing treatment with the two formulations. The spraying treatment of cauliflower with the formulations allowed the use of very small amounts of antimicrobials while maintaining a fairly good efficiency, greatly reducing the potential costs of implementing this method in the industry. Future research may focus on development of nanoemulsion of antimicrobial formulations based on the developed antimicrobial formulations in this study to improve the better coating efficiency.     

Kinetics of the liquid phase synthesis and hydrolysis of butyl lactate catalysed by cation exchange resin

Esterification of lactic acid with butanol catalysed by cation-exchange resin was carried out in a batch reactor in dioxane and toluene. The reaction rate was found to be first order with respect to catalyst and acid concentrations. The inhibiting effect of water and butanol has been evaluated. The rate data were correlated with a kinetic model based on inhibition by water and butanol.     

Shape-driven segmentation of the arterial wall in intravascular ultrasound images

Segmentation of arterial wall boundaries from intravascular images is an important problem for many applications in the study of plaque characteristics, mechanical properties of the arterial wall, its 3-D reconstruction, and its measurements such as lumen size, lumen radius, and wall radius. We present a shape-driven approach to segmentation of the arterial wall from intravascular ultrasound images in the rectangular domain. In a properly built shape space using training data, we constrain the lumen and media-adventitia contours to a smooth, closed geometry, which increases the segmentation quality without any tradeoff with a regularizer term. In addition to a shape prior, we utilize an intensity prior through a nonparametric probability-density-based image energy, with global image measurements rather than pointwise measurements used in previous methods. Furthermore, a detection step is included to address the challenges introduced to the segmentation process by side branches and calcifications. All these features greatly enhance our segmentation method. The tests of our algorithm on a large dataset demonstrate the effectiveness of our approach.     

ADSL调制解调器的保护线路接口设计

异步数字用户线路(ADSL)调制解调器由于同普通电话线相连,容易遭受电击。因此,必须施加恰当保护,以抵抗破坏性过压和压流的冲击。通晓保护标准、指导原则和器件,可以提高设计人员保护ADSL调制解调器的电话线及数据线免遭过压冲击的能力。如表1所示,标准的选择取决于设备类型、在网络中的位置和网络的地理区域。对于并联元器件,特别是具有急剧短路特性的器件,可以提供必要的雷电冲击保护功能。急剧短路器件的优点是可以高效地短接电话双绞线,消除过压,而且热量极小。在正常电压下,急剧短路器件保持开路状态。器件的电流处理能力取决于器…     

Assessment of regional left ventricular long-axis motion with MR velocity mapping in healthy subjects

We present a case of trichothiodystrophy associated with a hypereosinophilic syndrome. This case had been followed for 30 years. Trichothiodystrophy was characterized by lamellar ichthyosis, hair and nail dystrophies, kyphoscoliosis, congenital luxation of the hip. The hypereosinophilic syndrome was characterized by an itching urticaria-like eruption. Although the patient's general condition had remaining stable for 30 years, during the last year it worsened and the patient suddenly died. The authors discuss about the significance of this association.     

Prevalence and predictors of posttraumatic stress in women undergoing an ovarian cancer investigation.

This study assessed posttraumatic stress disorder (PTSD) in women being investigated for an ovarian cancer diagnosis to determine prevalence and factors predicting PTSD in these patients. Participants (N = 75) were recruited from the Princess Margaret Hospital in Toronto, Ontario, after their initial clinic appointment and given a prediagnostic assessment that included measures of PTSD, depression, stress and pain. One month later, patients received an identical postdiagnostic assessment. No cases of clinical PTSD were detected, although 13.6% of participants were identified with subsyndromal PTSD. Multiple regression analyses showed that those participants reporting significant baseline depressive symptoms, definitively diagnosed with ovarian cancer, and with shorter treatment wait times were more likely to have a significant increase in PTSD symptoms. Supportive interventions aimed at reducing PTSD symptoms, launched prior to an ovarian cancer diagnosis, might optimally be directed at patients with baseline depressive symptoms and those with shorter treatment wait times. (PsycINFO Database Record (c) 2010 APA, all rights reserved)