Urinary tract infections and pregnancy in women who underwent antireflux surgery in childhood

PURPOSE: For several decades ureteroneocystostomy has been performed in children to correct primary vesicoureteral reflux. A purported indication for antireflux surgery is to prevent significant upper urinary tract infection during pregnancy. We performed a long-term followup of women who underwent antireflux surgery during childhood to determine outcome in regard to urinary tract infection history and pregnancy. MATERIALS AND METHODS: We identified 227 women of childbearing age who underwent ureteral reimplantation for primary vesicoureteral reflux from 1964 through 1981. Of the 122 women contacted 41 had been pregnant (77 total pregnancies). Cystitis or asymptomatic bacteriuria and pyelonephritis developed during 18 and 5 pregnancies, respectively. The 77 pregnancies resulted in 57 term births, 7 voluntary pregnancy interruptions and 13 spontaneous abortions. RESULTS: Patients who previously underwent successful antireflux surgery continued to have a significant number of urinary tract infections through the intervening years. Despite a higher than expected incidence of pyelonephritis, they had relatively little hypertension and renal insufficiency. During pregnancy the incidence of pyelonephritis was only slightly higher than that of the general population. However, severe complications of pregnancy, such as preeclampsia, premature birth and acute renal failure, occurred more frequently in women with a history of renal scarring or hypertension (7 of 12) than in those with a history of recurrent infection alone (3 of 10). CONCLUSIONS: When renal scarring is present, reflux should be corrected before pregnancy to minimize maternal and fetal morbidity. When scarring is not present, the literature suggests that women with a history of reflux are at increased risk for pyelonephritis during pregnancy whether or not ureterocystostomy was performed. Pregnant women with a history of reflux may benefit from prophylactic antibiotics and women with reflux nephropathy should be followed throughout life.     

Kashin-Beck osteoarthropathy in rural Tibet in relation to selenium and iodine status

BACKGROUND AND METHODS: Kashin-Beck disease is a degenerative osteoarticular disorder that is endemic to certain areas of Tibet, where selenium deficiency is also endemic. Because selenium is involved in thyroid hormone metabolism, we studied the relation among the serum selenium concentration, thyroid function, and Kashin-Beck disease in 575 subjects 5 to 15 years of age in 12 villages around Lhasa, Tibet, including 1 control village in which no subject had Kashin-Beck disease. Clinical, radiologic, and biochemical data were collected. RESULTS: Among the 575 subjects, 280 (49 percent) had Kashin-Beck disease, 267 (46 percent) had goiter, and 7 (1 percent) had cretinism. Of the 557 subjects in whom urinary iodine was measured, 66 percent had a urinary iodine concentration of less than 2 microg per deciliter (157 nmol per liter; normal, 5 to 25 microg per deciliter [394 to 1968 nmol per liter]). The mean urinary iodine concentration was lower in subjects with Kashin-Beck disease than in control subjects (1.2 vs. 1.8 microg per deciliter [94 vs. 142 nmol per liter], P<0.001) and hypothyroidism was more frequent (23 percent vs. 4 percent, P=0.01). Severe selenium deficiency was documented in all villages; 38 percent of subjects had serum concentrations of less than 5 ng per milliliter (64 nmol per liter; normal, 60 to 105 ng per milliliter [762 to 1334 nmol per liter]). When age and sex were controlled for in a multivariate analysis, low urinary iodine, high serum thyrotropin, and low serum thyroxine-binding globulin values were associated with an increased risk of Kashin-Beck disease, but a low serum selenium concentration was not. CONCLUSIONS: In areas where severe selenium deficiency is endemic, iodine deficiency is a risk factor for Kashin-Beck disease.     

Model for coal oxidation kinetics. 2. An effectiveness factor interpretation

Rate expressions are developed to describe the oxidation of coal in a fixed-bed reactor under conditions of significant diffusional effects. The model defines individual effectiveness factors for carbonic gas formation, oxygen deposition, and water production, to modify a chemical model derived previously. Experiments carried out on seven coals ranging in rank from lignite to bituminous to anthracite. All the coals exhibited particle size effects and the results fit the model in most cases to within ±10% both in the rate of overall oxidation and with respect to the individual reaction rates for several products. Activation energies and effectiveness factors were obtained for each coal and for each reaction. The effluent gas $\text{CO}{}_2\text{CO}$ ratio was found to be virtually constant for all five bituminous coals, being independent of reaction temperature, coal particle size, and oxygen partial pressure.     

A modular approach for the design of microstrip array antennas

A method for the design of medium gain (15-25 dB) microstrip array antennas is described. A modular approach is utilized in which a given antenna is used as a building block for higher gain antennas. A series ofX-band antennas were built in this way, and the results seem to validate the usefulness of the method.     

Compatriot and foreigner: A study of impression formation in three countries.

An experimental study of the process that is called "the formation of first impression… . Our first and perhaps the most general hypothesis is that if objects that are alike in all respects save one are considered together, their difference in this one respect will be more critical in the impression one forms of the objects. Three identical triplets, differing only in the color of tie they are sporting, will be seen and interpreted more in terms of their tie-wearing habits than would be the case if each one were encountered singly and without the possibility of a simultaneous comparison. A corollary of this hypothesis to which we have addressed ourselves is: If in forming impressions of foreigners and compatriots one is thinking in a comparative context, with the different nationalities in mind while forming one's impression, then the degree to which nationality will influence the impressions formed will be increased." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial transform optical correlator design principles

Optical correlators such as the 4f and VanderLugt optical systems have been an active area of research for many years; we refer to these types of optical system collectively as serial transform correlators (STCs). Despite being well known, misconceptions regarding the design of STCs are not uncommon. We show, for example, that one correlator configuration reported to suffer from a phase curvature problem in fact works correctly. We present and prove a simple set of rules to follow in the selection of a STC design that does not contain unnecessary constraints and that makes it easier to identify permissible optical systems. As examples, we discuss three representative types of correlator configuration, one of which is discussed in detail to highlight its practical advantages. A novel proof of the design rules is presented that does not depend on details such as what lenses or combination of lenses are used, what their focal lengths are, or what their locations are within the optical system. We also present a conventional Fourier optics proof.     

What are shaping the ethical bottom line?: Identifying factors influencing young readers’ acceptance of digital news photo alteration

While most research on digital ethics has focused on professional codes or case studies in manipulation, there has been little formal research on what the readers thinks about what is and what is not visually ethical in a digital age. This study examines what affect young readers’ acceptance or rejection of digital alteration of news images. The major finding is that the perceived prevalence of photo alteration, media credibility, and personal Photoshop use and knowledge are the major influencers of “non-professional” standards of acceptance of photo alteration. The study implies the necessity of intervention from scholars, media professionals, and ethical activists to discuss photo alteration and advocate ethical standards for it.     

Geodesic Warps by Conformal Mappings

In recent years there has been considerable interest in methods for diffeomorphic warping of images, with applications in e.g. medical imaging and evolutionary biology. The original work generally cited is that of the evolutionary biologist D’Arcy Wentworth Thompson, who demonstrated warps to deform images of one species into another. However, unlike the deformations in modern methods, which are drawn from the full set of diffeomorphisms, he deliberately chose lower-dimensional sets of transformations, such as planar conformal mappings. In this paper we study warps composed of such conformal mappings. The approach is to equip the infinite dimensional manifold of conformal embeddings with a Riemannian metric, and then use the corresponding geodesic equation in order to obtain diffeomorphic warps. After deriving the geodesic equation, a numerical discretisation method is developed. Several examples of geodesic warps are then given. We also show that the equation admits totally geodesic solutions corresponding to scaling and translation, but not to affine transformations.