Differentiation between chondroma and squamous cell carcinoma: evaluation of subtraction image of MRI

The image processing procedure has become widely applied as a visual aid in imaging diagnosis. The subtraction image of MRI obtained by digitally subtracting an unenhanced image from a contrast-enhanced image, depicted a discrete distribution of the contrast agent. Subtraction images in the clinical cases were compared. The subtraction image in a case of chondroma demonstrated a relatively uniform distribution of a contrast agent, with a well delineated neoplastic lesion. The subtraction image in a case of squamous cell carcinoma, the contrast agent was distributed heterogeneously in the carcinoma and well permeated into the muscle. Different patterns of subtraction image were obtained in the clinical cases of chondroma and squamous cell carcinoma in this study. The findings suggest the potential usefulness of the subtraction image for diagnosing the degree of malignancy.     

坚持科技进步是企业发展的永恒主题

本文是宁波粉末冶金厂改革开放15年来坚持科技进步,使企业获得高速发展和壮大的经验总结。该厂通过技术和设备引进,走上依靠技术改造求发展的道路。其技改经历三个阶段,每个阶段目标明确,投资见效快,粉末冶金制品的年生产能力“六五”末期为450t,“七五”末期跃到1200t,“八五”后期达到2500t。“九五”技改规划实施后,目前金鸡集团内四个企业专业生产粉末冶金制品年生产能力达到7000t,固定资产原值已达到1．35亿元,生产经营规模和产品水平又登上了新的台阶。     

Participation in workplace design with reference to low back pain: a case for the improvement of the police patrol car

Thirty Canadian police officers, divided into six groups, participated in the redesign of the interior of the patrol car. Three of the groups consisted of individuals having a history of low back disease. The effect of participating in a design process on the characteristics of the final design and on the perception of the low back pain was studied in a semi-experimental setting. The participants developed a strong commitment to the participatory design process, which was reflected in their productions. The differences between participants with and without a history of a low back disease was not marked. The former tended to stress posture-related elements in their analysis and design.     

Lung inflammation in patients with systemic lupus erythematosus detected by quantitative 67Ga-citrate lung scanning

The severity of lung inflammation in 34 patients with systemic lupus erythematosus (SLE) was measured by quantitative 67Ga-citrate lung scanning. The severity of lung inflammation in SLE was represented by the 67Ga uptake index (GUI). Quantitative 67Ga lung scanning was also performed on 20 normal controls for comparison with the SLE patients. The patients were divided into two subgroups according to the following two criteria: (a) stable or flare stage according to clinical features; or (b) positive or negative results of chest X-ray. The GUI values of the subgroups were also compared. The results revealed a trend towards higher values of GUI in SLE patients than in the normal controls. The GUI values were also higher for SLE cases with a flare stage or a negative chest X-ray than in SLE cases with a stable stage or a positive chest X-ray. The statistical results reveal that the differences in the GUI values are not significant. However, we found that (1) positive chest X-ray findings may be a later manifestation of a lung inflammation and (2) the values of GUI parallel clinical features in SLE patients.     

Stresses,deformations and porosities in standard fracture specimens

The stresses, deformations and porosities in vicinity of a blunting crack in different specimens were studied by a large-deformation finite element method. The presence and subsequent growth of smaller-scale voids were taken into account by using a modified Gurson model to describe the constitutive behavior of the material. The dependence of the stresses, deformations and porosities on specimen configurations was associated with the crack-tip constraint. The results showed that the constraint of different specimens was lower than that of the HRR singularity. The interaction between a crack and a hole in CT specimen was analyzed, and the results showed that the critical COD (crack tip opening displacement) was larger than that obtained in SSY model. The complete loss of the total carrying capacity in a ligament between the crack-tip and the hole was recommended as a crack initiation criterion.     

Probabilistic Approach for Budgeting in Portfolio of Projects

This paper presents a mathematical model for calculating the budgetary impact of increasing the required confidence level in a probabilistic risk assessment for a portfolio of projects. The model provides a rational approach for establishing a probabilistic budget for an individual project in such a way that the budget for a portfolio of projects will meet a required confidence level. The use of probabilistic risk assessment in major infrastructure projects is increasing to cope with major cost overruns and schedule delays. The outcome of the probabilistic risk assessment is often a distribution for project costs. The question is at what level of confidence (i.e., the probability that budget would be sufficient given the cost distribution) should be used for establishing the budget. The proposed method looks at a portfolio of such projects being funded by the same owner. The owner can establish a target probability with respect to its annual budget. The model can help the owner establish confidence level for individual projects and also examine the effect of changing the confidence level of the portfolio budget on the budget and the confidence level of individual projects. The paper is relevant to practitioners because it provides a methodology for establishing confidence levels by the owner agencies in the emerging field of cost risk assessment for infrastructure projects. A numerical example is provided using actual transit project data to demonstrate the model application.     

Development of the process of electric steel production and methods for improving the technical-and-economic indices of electric arc furnaces

The structure of the metal losses during melting of a low-carbon semiproduct in EAF is analyzed. It is shown that a further increase in the capacity of a modern superpower EAF can degrade the technical-and-economic indices of its operation. The increase in the metal losses in melting in EAF is caused by a high oxygen flow rate and a number of other technological factors. The rational methods of increasing the technical-and-economic indices of EAF are a decrease in the metal losses in melting and processing of the semiproduct, a decrease in the primary energy consumption, and the recycling of dust and waste slags.     

The use of Holmstrom's flap in breast reconstruction

The authors consider 12 cases of breast-reconstruction after mastectomy, made with the Holmstrom's flap, to verify the validity and the real utility of this way of reconstruction. It has been made a follow-up of 4 years, to verify, in course of time, the characteristics of the reconstructed breasts. All the patients have been operated in a general surgery department. The Holmstrom's flap has been prevalently used in patients, during immediate reconstruction. The breast reconstruction, made with this fascio-cutaneous transposition flap, requires the use of prosthesis. The operating time has a very short duration. The breast reconstruction, made with this method, requires a very short staying in hospital. The nipple-areola complex reconstruction has been made in a second time, few months later. The patients have been examined periodically, to verify, immediately, the result of the flap and, later, the quality of the new breast's shape and the occurrence of capsular contracture. The results achieved with this reconstructive method are a good shape and ptosis as to confer great naturalness to the new breast. The authors conclude that, even if they use the TRAM-flap as first choice in breast-reconstruction, the Holmstrom's flap is a reconstructive technique of great utility in immediate breast reconstruction, that is able to give very good aesthetic results.     

Formation of gas-saturated defects in titanium alloys during vacuum-arc remelting

The formation of gas-saturated defects in titanium alloys during vacuum-arc remelting is studied theoretically and experimentally. The defects of a metallurgical origin that were detected upon long-term monitoring of a commercial process of production are considered. The light-element contents are determined with a high-locality nuclear accelerator microanalysis technique. A theoretical model is developed to describe the dissolution of solid gas-saturated inclusions in liquid titanium; it is based on a mechanism of diffusion of modifying defects in melting. The critical parameters of defect sources (defect size, nitrogen concentration in a defect) at which defects do not dissolve in titanium upon melting are determined. The obtained dependence of the average light-element concentration in a defect on the defect size is explained.     

Post-decision consolidation, as a function of the instructions to the decision maker and of the decision problem

The effects of instructions and decision problems on post-decision processes were studied by varying the instructions to subjects. Subjects made a medical policy decision based on information on four attributes in Experiments 1-2. The subjects were given different instructions: (1) no instruction at all about a second session, (2) instruction to remember his/her decision until a session a week later, and (3) instruction to justify the decision at a later occasion one week later. The results indicated post-decision consolidation in the first group, as predicted by the Differentiation and Consolidation Theory (Svenson, 1992). The effect showed up in attractiveness restructuring in support of the chosen alternative on the most important attributes. The instruction to remember the decision until a later time increased the consolidation effect. Contrary to our expectations, the instruction to later justify the decision did not produce any consolidation. This effect was replicated in the second experiment and could not be interpreted as a random result. In a third experiment the decision problem was framed as an environmental pollution problem and it was preceded by a carefully designed booklet presenting arguments for and against different materials used in manufacturing packages for coffee. Subjects were then asked to make a choice of the same coffee in two different packages. The data indicated no difference in structural consolidation as a result of the instruction to justify or not. The paper concludes with a discussion pointing out the importance of the involvement in a decision task for decision differentiation and consolidation.     

Toward a Full Simulation of the Basic Oxygen Furnace: Deformation of the Bath Free Surface and Coupled Transfer Processes Associated with the Post-Combustion in the Gas Region

The present article treats different phenomena taking place in a steelmaking converter through the development of two separate models. The first model describes the cavity produced at the free surface of the metal bath by the high-speed impinging oxygen jet. The model is based on a zonal approach, where gas compressibility effects are taken into account only in the high velocity jet region, while elsewhere the gas is treated as incompressible. The volume of fluid (VOF) method is employed to follow the deformation of the bath free surface. Calculations are presented for two- and three-phase systems and compared against experimental data obtained in a cold model experiment presented in the literature. The influence on the size and shape of the cavity of various parameters and models (including the jet inlet boundary conditions, the VOF advection scheme, and the turbulence model) is studied. Next, the model is used to simulate the interaction of a supersonic oxygen jet with the surface of a liquid steel bath in a pilot-scale converter. The second model concentrates on fluid flow, heat transfer, and the post-combustion reaction in the gas phase above the metal bath. The model uses the simple chemical reaction scheme approach to describe the transport of the chemical species and takes into account the consumption of oxygen by the bath and thermal radiative transfer. The model predictions are in reasonable agreement with measurements collected in a laboratory experiment and in a pilot-scale furnace.     

An unusual form of macrodactyly

The authors report a rare case of macrodactyly of the thumb in a 36 year old woman. The hypertrophy predominates on the epiphyseal tissue with complete ankylosis of the trapezo-metacarpal joints. The metacarpo-phalangeal joint and interphalangeal joints in an abnormal position. This results total functional incapacity of the thumb. The cosmetic and psychological impact are important to consider. Treatment consisted of two operative procedures. First a silastic implant for the trapezo-metacarpal joint and an arthrodesis of the metacarpophalangeal joint in a normal position was done. Three months later, the volume of the thumb was reduced by a longitudinal bone resection. The functional and cosmetic result are being assessed. The literature is reviewed and the different modes of treatment utilised in such a malformation is presented. A relation between macrodactyly and lipomatous macrodystrophy is considered.     

The protective action of tocopherol acetate in simultaneous administration with nitrobenzene and its chloro derivatives]

In this article the results of the study of regularities in the development of outbreak morbidity in shigellosis, caused by S.flexneri 2a, in hospitals are presented. The study was carried out with the use of the method of typing by the plasmid profile. The study showed the continuity of the epidemic process in the foci which appeared at intervals considerably exceeding the incubation period. The fact of the interhospital spread of S.flexneri 2a was established. The strain causing the disease was identified by the characteristic set of plasmids and their size. The possibility of reinfection of patients with S.flexneri 2a under hospital conditions was confirmed. The possibility of changes in the main transmission routes in the course of the spread of S.flexneri 2a infection in closed groups was pointed out.     

Reactive arthritis and erythema multiforme caused by Salmonella dublin

In situ split of the liver was performed in a heart-beating cadaveric organ donor for the first time in the U.S.A. by two geographically distant transplant centers. The procedure, initiated by a transplant team in Oklahoma City, was a joint project of the transplant teams from Oklahoma City and New York City. The in situ split resulted in two liver grafts. A left graft (left lateral segment) which was transplanted into a 7-year-old pediatric recipient in Oklahoma City and a right graft (right lobe and segment IV) which was transplanted into a 52-year-old adult recipient in New York City. Initial graft function was excellent in the two patients. The adult recipient was discharged home 10 days after the transplant and is doing well. The pediatric recipient died two and a half months later from multi-system organ failure. The recently introduced in situ split technique provides two excellent liver grafts from one donor and enhances sharing of liver grafts between transplant centers.     

Clines with variable migration

The consequences of a discontinuity in the migration rate and of a geographical barrier in the habitat are studied in a diffusion model of migration and selection. The treatment is restricted to a single diallelic locus in a monoecious population in the absence of mutation and random drift. It is supposed further that migration is independent of genotype, the population density remains constant and uniform, and Hardy-Weinberg proportions obtain locally. It is shown that a discontinuity in the migration rate leads to a jump in the slope of the gene frequency, but not in the gene frequency itself, while a localized geographical barrier has precisely the opposite effect. These features of the gene frequency behavior are quantitatively related to the migration rate. The influence of the above inhomogeneities in migration on the maintenance of an allele in an environmental pocket is examined. The extent to which the critical condition for polymorphism is made less stringent by decreased migration outside the pocket and by a geographical barrier between the pocket and the rest of the habitat is evaluated.     

Follow-up and family study of postpartum psychoses. Part I: Overview

A group of 119 patients suffering from a severe psychiatric postpartum disorder who were admitted for the first time in their life to a psychiatric hospital has been investigated. The onset of illness occurred within 3 months following delivery. The patients represented 92% of the total sample fulfilling the inclusion criteria. A follow-up investigation was performed after a mean of 21 years (range 2-35 years). Of the patients 66% had nonpuerperal psychotic episodes in later life. The diagnosis, taking into account the long-term course, was affective psychosis in 57%, schizoaffective psychosis in 18%, schizophreniform psychosis in 12%, brief reactive psychosis in 4% and schizophrenia in 9%. A bipolar psychosis was found in 31%. The relation of unipolar to bipolar psychoses corresponded to that in a control group of affectively ill women without puerperal onset. The frequency of a manic syndrome in bipolar psychoses at the index episode was the same as in nonpuerperal episodes, which does not suggest a mania-provoking pathoplastic effect of the puerperium. The comparison with female nonpuerperal controls matched for age and diagnosis revealed evidence of a better long-term course in the index patients. The risk of a puerperal relapse for further pregnancies was 35%. The global morbidity risk for functional psychoses in first-degree relatives was 11%, with affective psychoses representing the majority of secondary cases (6.8%). The index patients showed a nonsignificant lower morbidity risk in relatives than a control group of psychotically ill women without puerperal onset. The major aetiological factor found for postpartum psychoses is the relation of these disorders to functional psychoses. There is strong evidence that the postpartum period tends to provoke affective psychoses and other nonschizophrenic psychoses, but not, or only to a lesser degree, narrowly defined schizophrenias. The liability to puerperal decompensations suggests some common pathophysiological mechanism, the nature of which remains unknown.     

Interaction of a copper oxide particle with copper in drawing

The forming of copper near a copper oxide particle is determined during multiple-pass drawing. The interaction of the copper oxide particle with copper is studied by the calculation of the state of stress in a finite element formulation and using scanning electron microscopy data. The results obtained demonstrate that pores appear around copper oxide particles when strain accumulates in multiple-pass drawing machines. The pore length increases with the accumulated strain, which can result in breaks of a wire in a highly cold-worked state.     

Hydration structure of a collagen peptide

BACKGROUND: The collagen triple helix is a unique protein motif defined by the supercoiling of three polypeptide chains in a polyproline II conformation. It is a major domain of all collagen proteins and is also reported to exist in proteins with host defense function and in several membrane proteins. The triple-helical domain has distinctive properties. Collagen requires a high proportion of the post-translationally modified imino acid 4-hydroxyproline and water to stabilize its conformation and assembly. The crystal structure of a collagen-like peptide determined to 1.85 Angstrum showed that these two features may be related. RESULTS: A detailed analysis of the hydration structure of the collagen-like peptide is presented. The water molecules around the carbonyl and hydroxyprolyl groups show distinctive geometries. There are repetitive patterns of water bridges that link oxygen atoms within a single peptide chain, between different chains and between different triple helices. Overall, the water molecules are organized in a semi-clathrate-like structure that surrounds and interconnects triple helices in the crystal lattice. Hydroxyprolyl groups play a crucial role in the assembly. CONCLUSIONS: The roles of hydroxyproline and hydration are strongly interrelated in the structure of the collagen triple helix. The specific, repetitive water bridges observed in this structure buttress the triple-helical conformation. The extensively ordered hydration structure offers a good model for the interpretation of the experimental results on collagen stability and assembly.     

Electrochemical measurement of lateral diffusion coefficients of ubiquinones and plastoquinones of various isoprenoid chain lengths incorporated in model bilayers

The long-range diffusion coefficients of isoprenoid quinones in a model of lipid bilayer were determined by a method avoiding fluorescent probe labeling of the molecules. The quinone electron carriers were incorporated in supported dimyristoylphosphatidylcholine layers at physiological molar fractions (<3 mol%). The elaborate bilayer template contained a built-in gold electrode at which the redox molecules solubilized in the bilayer were reduced or oxidized. The lateral diffusion coefficient of a natural quinone like UQ10 or PQ9 was 2.0 +/- 0.4 x 10(-8) cm2 s(-1) at 30 degrees C, two to three times smaller than the diffusion coefficient of a lipid analog in the same artificial bilayer. The lateral mobilities of the oxidized or reduced forms could be determined separately and were found to be identical in the 4-13 pH range. For a series of isoprenoid quinones, UQ2 or PQ2 to UQ10, the diffusion coefficient exhibited a marked dependence on the length of the isoprenoid chain. The data fit very well the quantitative behavior predicted by a continuum fluid model in which the isoprenoid chains are taken as rigid particles moving in the less viscous part of the bilayer and rubbing against the more viscous layers of lipid heads. The present study supports the concept of a homogeneous pool of quinone located in the less viscous region of the bilayer.     

Dissolution behavior and bioavailability of phenytoin from a ground mixture with microcrystalline cellulose

The ground mixture of phenytoin and microcrystalline cellulose was prepared by grinding in a vibrational ball mill. The X-ray diffraction patterns indicated the amorphous nature of the ground mixture. Comparative studies were made concerning the in vitro dissolution and in vivo absorption of fine phenytoin powder, phenytoin sodium powder, and the ground mixture. The ground mixture showed a greater dissolution rate than the fine powder and attained supersaturation in the pharmacopeial disintegration media at pH 1.2 and 7.4. In vivo absorption studies of each preparation were carried out in five subjects, using a crossover design, by measuring the urinary excretion rate of a main metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin. The blood levels of phenytoin and the corresponding urinary excretion patterns of the metabolite were determined in two subjects. The ground mixtures significantly improved the bioavailability of phenytoin. The drug was completely and rapidly absorbed after oral administration of the ground mixture. The vibrational ball milling technique for a poorly water-soluble drug with microcrystalline cellulose provides a promising way of improving the in vivo drug absorption.