Search

The hunter and gatherer approach copes with the problem of dynamic multi-robot task allocation, where tasks are unknowingly distributed over an environment. This approach employs two complementary teams of agents: one agile in exploring (hunters) and another dexterous in completing (gatherers) the tasks. Although this approach has been studied from the task planning point of view in our previous works, the multi-robot exploration and coordination aspects of the problem remain uninvestigated. This paper proposes a multi-robot exploration algorithm for hunters based on innovative notions of "expected information gain" to minimize the collective cost of task accomplishments in a distributed manner. Besides, we present a coordination solution between hunters and gatherers by integrating the novel notion of profit margins into the concept of expected information gain. Statistical analysis of extensive simulation results confirms the efficacy of the proposed algorithms compared in different environments with varying levels of obstacles complexities. We also demonstrate that the lack of effective coordination between hunters and gatherers significantly hurts the total effectiveness of the planning, especially in environments containing dense obstacles and confined corridors. Finally, it is statistically proven that the overall workload is distributed equally for each type of agent which ensures that the proposed solution is not biased to a particular agent and all agents behave analogously under similar characteristics., Comment: 17 pages, 11 figures. arXiv admin note: text overlap with arXiv:1912.05748

Background Scapholunate interosseous ligament injuries are common but remain a therapeutic challenge. Current treatment modalities prioritize restoration of normal anatomy with reconstruction where appropriate. To date no reconstructive technique has been described that discusses the potential benefit of preservation of the scapholunate ligament remnant. Little is known about the “ligamentization” of grafts within the wrist. However, a growing body of knee literature suggests that remnant sparing may confer some benefit. In the absence of wrist specific studies, this literature must guide areas for potential augmentation of current surgical practices. Objective The purpose of this study was to perform a review of the process of ligamentization and a systematic review of the current literature on the possible role of ligament sparring and its effect on ligamentization. Methods A systematic search of the literature was performed to identify all the studies related to remnant sparing and the ligamentization of reconstructed tendons, regardless of graft type or joint involved from MEDLINE, EMBASE, and PubMed until February 1, 2016 using the following keywords: ligamentization, graft, remodelling, reconstruction, biomechan*, histolo∗, scapholunate ligament. Each selected study was evaluated for methodological quality and risk of bias according to a modified Systematic Review Center for Laboratory Animal Experimentation criteria. Conclusions The available literature suggests that ligament sparring demonstrated a trend toward improvements in vascularity, mechanoreceptors, and biomechanics that lessens in significance over time. Clinical Relevance This review suggests that remnant sparing may be one way to improve outcomes of scapholunate ligament reconstructive surgery. Level of Evidence This is a level I/II, review study.

Psi4 is an ab initio electronic structure program providing methods such as Hartree-Fock, density functional theory, configuration interaction, and coupled-cluster theory. The 1.1 release represents a major update meant to automate complex tasks, such as geometry optimization using complete-basis-set extrapolation or focal-point methods. Conversion of the top-level code to a Python module means that Psi4 can now be used in complex workflows alongside other Python tools. Several new features have been added with the aid of libraries providing easy access to techniques such as density fitting, Cholesky decomposition, and Laplace denominators. The build system has been completely rewritten to simplify interoperability with independent, reusable software components for quantum chemistry. Finally, a wide range of new theoretical methods and analyses have been added to the code base, including functional-group and open-shell symmetry adapted perturbation theory (F-SAPT and O-SAPT), density-fitted coupled cluster with frozen natural orbitals [DF-FNO-CCSD(T)], orbital-optimized perturbation and coupled-cluster methods (e.g., OO-MP2 and OO-CCSD), density-fitted multiconfigurational self-consistent field (DF-MCSCF), density cumulant functional theory (DCT), algebraic-diagrammatic construction [ADC(2)] excited states, improvements to the geometry optimizer, and the “X2C” approach to relativistic corrections, among many other improvements.

In 1965, the specialty of paediatric nephrology was in its infancy. Following the development of a landmark collaborative research study, the International Study of Kidney Disease in Childhood in the mid-1960s, the first specialist societies were formed: the European Society of Pediatric Nephrology in 1967 and the American Society of Pediatric Nephrology in 1969. The extraordinary improvements in care delivered to children with kidney disease over the past 50 years are too broad to cover in any one paper. They traverse the spectrum of diagnosis, classification, therapeutics, social well-being and transition to adult care. We have selected four case scenarios to highlight these changes in key areas of paediatric nephrology: post-streptococcal glomerulonephritis, nephrotic syndrome, haemolytic uraemic syndrome and neonatal dialysis and childhood transplantation.

The measurement of power factor (PF) in electrical utility grids is a mainstay of load balancing and is also a critical element of transmission and distribution efficiency. The measurement of PF dates back to the earliest periods of electrical power distribution to public grids. In the wide-area distribution grid, measurement of current waveforms is trivial and may be accomplished at any point in the grid using a current tap transformer. However, voltage measurement requires reference to ground and so is more problematic and measurements are normally constrained to points that have ready and easy access to a ground source. We present two mathematical analysis methods based on kriging and linear least square estimation (LLSE) (regression) to derive PF at nodes with unknown voltages that are within a perimeter of sample nodes with ground reference across a selected power grid. Our results indicate an error average of 1.884% that is within acceptable tolerances for PF measurements that are used in load balancing tasks.

Advances in technology has allowed us to demand for high speed and low power devices in modern chips. These transistors are scaled down and examined with multi-gate architecture in order to improve electrostatic control over the channel and reduce power consumption. A novel dual-gate gate-all-around (GAA) junctionless nanowire transistor (JNT) is addressed in this work. Using TCAD device modeling, we report a process variability analysis and explored the device characteristics. A cylindrical nanowire with a channel length of 10 nm and a diameter of 5 nm is employed to study the process sensitivity of the device. A 1 nm thick HfO2 gate is used as a dielectric material. Analysis from deep depletion to strong accumulation mode with a 2e19 cm−3 n-type channel doping (Vds = 0.8V and T = 300 K) is reported. The dual-gate GAA JNT shows an improved electrical behavior with a variation to channel doping, channel diameter, channel length and oxide thickness. It also has an enhanced short channel behavior such as high Ion/Ioff (>106), good sub threshold slope (∼68 mV/decade) and low drain induced barrier lowering (∼8mV/V) compared to conventional inversion mode transistors and regular nanowire GAA devices that makes the device a candidate for energy efficiency improvements.

Advances in short channel transistor technology has allowed the emergence of these devices in modern chips. These transistors experience many different types of Short Channel Effects (SCE) that are addressed in this work. Using TCAD simulations, we report a new and effective technique to reduce SCE in a novel dual-gate silicon nanowire Gate-All-Around (GAA) junctionless transistor. A channel length of 10 nm and a diameter of 5 nm is employed to mitigate SCE in terms of Subthreshold Slope (SS), Leakage current (Ioff) and Drain Induced Barrier Lowering (DIBL). A 1 nm thick HfO2 gate is used as a dielectric material. Analysis from deep depletion to strong accumulation mode with 2e19 cm−3 n-type channel doping (Vds = 0.8V and T = 300 K) is reported. The dual-gate GAA junctionless nanowire transistor shows improved electrical characteristics such as high Ion/Ioff (>106), good subthreshold slope (∼68 mV/decade) and low drain induced barrier lowering (∼8mV/V) compared to conventional inversion mode transistors and single nanowire GAA devices that makes the device a candidate for energy efficiency improvements.

BACKGROUND: The calcium-sensing receptor regulates the secretion of parathyroid hormone in response to changes in extracellular calcium concentrations, and mutations that result in a loss of function of the receptor are associated with familial hypocalciuric hypercalcemia. Mutations involving a gain of function have been associated with hypocalcemia in two kindreds. We examined the possibility that the latter type of mutation may result in a phenotype of familial hypocalcemia with hypercalciuria. METHODS: We studied six kindreds given a diagnosis of autosomal dominant hypoparathyroidism on the basis of their hypocalcemia and normal serum parathyroid hormone concentrations, a combination that suggested a defect of the calcium-sensing receptor. The hypocalcemia was associated with hypercalciuria, and treatment with vitamin D resulted in increased hypercalciuria, nephrocalcinosis, and renal impairment. Mutations in the calcium-sensing-receptor gene were identified by DNA-sequence analysis and expressed in human embryonic kidney cells (HEK-293). RESULTS: Five heterozygous missense mutations (Asn118Lys, Phe128Leu, Thr151Met, Glu191Lys, and Phe612Ser) were detected in the extracellular domain of the calcium-sensing-receptor gene and shown to cosegregate with the disease. Analysis of the functional expression of three of the mutant receptors in HEK-293 cells demonstrated shifts in the dose-response curves so that the extracellular calcium concentrations needed to produce half-maximal increases in total inositol phosphate in the cells were significantly (P=0.02 to P

Objectives: Darbepoetin alfa (Aranesp®) is a novel erythropoiesis stimulating protein that has beenshown in adult trials to have safety and tolerability equivalent to recombinant human erythropoietin.However, to date there is only limited published data on the use of Aranesp inpaediatric patients.The objective of this study was to determine the safety and efficacy of darbepoetin in children withchronic and endstage kidney disease.Methods: From 2003 to 2006, 30 children with either chronic or end stage kidney disease wereenrolled in a prospective observational study. The initialdose of darbepoetin was 0.45 mcg/kgweekly (either IV or SC) and subsequent dose was titrated to achieve haemoglobin (Hb) between110 and 130 g/dl.Results: Data analysis to date includes 22 patients (16 male : 6 female) whose agesranged from 1month to 17 years (mean 9 years). Hb improved significantly with darbepoetin treatment from mean84 g/dl (range 64-107) at start of treatment to 115 g/dl (range 81-147, p

The design is intended for aircraft although any vehicle or even a man-mobile system could use the concept. An automatically reconfigurable antenna using MEMS RF switches is driven to seek signals consistent with the current location of the system. The antenna feeds a Software Defined Radio (SDR) that scans for signals and when a signal is found, it is identified and then the azimuth to the signal is used, along with a signal strength parameter, to confirm the location of the system. This is an extension of the now obsolete Automatic Direction Finder (ADF) aircraft navigation tool that used AM broadcast non-directional beacons (NDB), many of which are still in service. The current system can access any radio signal within the limits of the reconfigurable antenna and the SDR.

The outcome of transplantation from grandparent donors in comparison with parental donors in paediatric renal transplantation was evaluated in 53 living related donor (LRD) transplantations performed between January 1996 and August 2003. The donor in 13 cases (25%) was a grandparent (Gpar group), and the remaining donors formed the parent group (Par group). The median age of recipients in the Gpar group was 2.75 (1.7-10.6) years and in the Par group was 12.75 (2.4-22) years (P

The rapid increase in the development of digital video systems has generated a strong need for objective video quality metrics. Two methods are presented in this work. One is the Gabor difference analysis (GDA) full reference method, and the other is the reverse frame prediction (RFP) no reference video quality method. Both methods are based on the multi-channel properties of the human visual system (HVS). Gabor filtering is used in both methods. In the GDA method, a reference and a degraded digital video sequence are compared by taking into account various psycho-perceptual properties of the HVS. The RFP method does not require a reference video stream and is intended for in-service testing and on-line monitoring. The performances of the proposed methods are evaluated. The methods in this work are shown to be consistent with the data from subjective testing over a wide range of scenes. This work is critical to the evaluation of the effectiveness of compression schemes on HDTV imagery.

The aim of this study was to establish the prevalence of anemia in stable pediatric renal transplant recipients and to examine the association of anemia with renal function, immunosuppressants, angiotensin converting enzyme inhibitors, and growth, as well as iron, vitamin B(12), and folate stores. This is a cross-sectional study of the 50 renal transplant recipients currently followed at our center. Patient data were collected regarding hematological parameters, growth, medications, renal function, underlying renal disease, delayed graft function, episodes of rejection, and iron or erythropoietin therapy post transplantation. The mean hemoglobin level (Hb) was 110 g/l and the overall prevalence of anemia was 60%, including 30% who were severely anemic (Hb100 g/l). There was a high rate of iron deficiency (34%) and serum iron was the parameter of iron metabolism most closely associated with anemia. Hb in patients with low serum iron was 90.7 g/l versus 114.4 g/l in those with normal serum iron ( P0.01). Both univariate and multiple linear regression determined tacrolimus dose and creatinine clearance to be significant factors associated with anemia. Tacrolimus dose correlated with a 10 g/l reduction in Hb for every increase of tacrolimus dose of 0.054 mg/kg per day ( P=0.001). The dose of mycophenolate was positively correlated with Hb, but this was likely to be confounded by our practice of dose reduction in the setting of anemia. Angiotensin converting enzyme inhibitor use was not associated with anemia. Severely anemic patients tended to be shorter, with a mean Z-score for height of -1.8 compared with -0.9 for those with normal Hb ( P=0.02). Anemia is a significant and common problem in pediatric renal transplant patients. Deteriorating renal function is an important cause, but other factors like iron deficiency and immunosuppression are involved. Definition of iron deficiency is difficult and serum iron may be a valuable indicator. Medication doses, nutritional status, need for erythropoietin and iron, as well as poor graft function and growth require systematic scrutiny in the care of the anemic renal transplant recipient.

Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are two related conditions caused by mutations of the Wilms tumor gene, WT1. Both syndromes are characterized by male pseudohermaphroditism, a progressive glomerulopathy, and the development of genitourinary tumors. DDS and FS have previously been distinguished by differences in nephropathy, with DDS patients demonstrating diffuse mesangial sclerosis (DMS) in contrast to focal and segmental glomerulosclerosis (FSGS) in FS patients. The clinicopathological features and genotype analysis of two patients with WT1 mutations are presented in this report. Genotype analysis of the first patient revealed a previously undescribed mutation in exon 8 of the WT1 gene. The second patient presented with a rapidly progressive nephropathy characterized histologically by DMS, but was found to have the genetic mutation seen in FS patients. A summary of all reported patients with the characteristic mutation associated with FS demonstrates the clinical overlap of this syndrome with DDS. This suggests that both these conditions should be considered as part of the spectrum of disease due to WT1 gene mutations rather than as separate diseases. Clinical classification remains important for prognosis, as the underlying renal disease appears to predict the progression of nephropathy independently of the genetic abnormality.

Left ventricular abnormalities in children, adolescents and young adults with renal disease. The cardiac abnormalities that complicate chronic renal failure and renal replacement therapy are not well characterized in young people. These abnormalities are becoming more important because successful renal transplantation has resulted in children with end-stage renal failure living longer. Echocardiographic abnormalities of cardiac function and structure were studied in children and young adults (< 27 years old) with chronic renal failure (CRF, N = 32), end-stage renal failure treated with chronic peritoneal dialysis (CPD, N = 10) or renal transplantation (N = 30) or controls (N = 60). Left ventricular mass indexed for height (LVM/Ht and LVM/Ht2.7) and body surface area (LVM/SA), fractional shortening, measurement of left ventricular diastolic function (peak E and A wave velocities and the E/A ratio) and structural (such as valvular) abnormalities were determined by echocardiography. The median (and range) of LVM/Ht in the groups were control 51.8 (23.1 to 119.8), CRF 60.2 (22.2 to 135.8), CPD 80.2 (44.5 to 100.9) and transplant group 97.8 (51.2 to 182.1) g/m. The increases in LVM/Ht, LVM/Ht2.7 and LVM/SA in the transplant group were significant (P < 0.01). The CRF group had significantly increased LVM/Ht2.7 and LVM/SA (P < 0.01). Systolic function was not significantly different between the groups. A significant correlation between creatinine and LVM indexed for height was found in the CRF group. Systolic or diastolic blood pressure could not be correlated with LVM indices in the transplant group. Changes in diastolic function were found (increased peak A wave velocity and decreased E/A ratios in the CRF and CPD groups, and increased peak E wave velocity in the transplant group). The study demonstrated that left ventricular hypertrophy is a frequent and often severe finding in children with chronic renal failure and those treated with renal replacement therapy. Factors other than hypertension and anaemia are important, and evidence was found for a link between serum creatinine and increased left ventricular mass prior to end-stage renal failure.

Results of renal transplantation in very young children with end-stage chronic renal failure have been poor compared with those in older children and adults. Consequently small children either may not be treated or may be placed on chronic dialysis programmes. Between 1988 and 1992, six children under the age of 5 years received seven renal transplants at the Royal Children's Hospital, Parkville, Victoria, Australia; five from live donors and two from cadaver donors. All children were treated with peritoneal dialysis before transplantation, and immunosuppressed with a standardized regimen of cyclosporine, azathioprine and prednisolone. An extraperitoneal incision was used, and the donor renal vessels were anastomosed to the lower abdominal aorta and inferior vena cava or the common iliac vein. All children received intensive monitoring and fluid replacement during the peri-operative period. Patient survival was 100%. One cadaver graft failed 1 week after transplantation because of irreversible acute rejection. This child subsequently received a successful second transplant. Two children developed postoperative urinary fistulae which were treated successfully by further operation. Current renal function in all children is excellent. The success of this programme has led us to review our attitude towards renal transplantation in this age group and to advocate live donor renal transplantation as the treatment of choice in very young children with end-stage chronic renal failure whenever possible.

Defects seen on early cortical scintigrams of the renal cortex in children with urinary tract infection may represent acute inflammatory change or established scar. The purpose of this study was to determine the relationship between these defects and age, sex, the presence and grade of vesicoureteral reflux, and infective organism in a cohort of children examined after their first proved urinary tract infection.We prospectively examined 193 consecutive patients less than 5 years old who were seen at the ambulatory pediatric department during a 3-year period and had a first proved urinary tract infection. Children with obstructed or solitary kidneys were excluded. All patients were imaged with scintigraphy of the renal cortex and radiographic voiding cystourethrography within 15 days of diagnosis. The association of age, sex, the presence and grade of vesicoureteral reflux, and infective organism with a defect (acute pyelonephritis or a renal scar) seen on a cortical renal scan was studied.The prevalence of cortical defects was greater in the kidneys of patients less than 2 years old (96/290, 33%) than in older children (16/96, 17%) and greater in those with vesicoureteral reflux (41/92, 45%) than in those without it (71/294, 24%). Vesicoureteral reflux was absent in 63% (71/112) of kidneys with a cortical defect. No association with sex or infective organism was established. As well as having a greater prevalence of cortical defects, 145 (75%) of the 193 urinary tract infections included in the study were in children less than 2 years old. The kidneys of these younger patients also had a greater severity and prevalence of vesicoureteral reflux (74/290, 26%) than did those of older children (18/96, 19%).Early cortical defects are associated with an age less than 2 years and vesicoureteral reflux. However, the association of early defects with the presence and grade of vesicoureteral reflux is confounded by the declining prevalence and severity of reflux with age. A significant proportion of cortical defects occur in the absence of vesicoureteral reflux, and the contribution of reflux to scar formation might be less than previously considered.

It has been claimed that low protein diets slow deterioration of chronic renal failure (CRF) by reducing renal solute load. The anabolic effect of recombinant human growth hormone (rhGH) also has potential to reduce renal solute load and thereby slow progression of renal failure. The aim of this study was to determine the effect of rhGH on growth, renal solute load and renal function in children with CRF. Seven prepubertal children, aged 2-14 years, with moderately severe CRF (creatinine clearance 7.7-23.4 mL/min per 1.73m2) were treated with daily subcutaneous rhGH, 1 U/kg per week for 10-12 months. As expected, mean height velocity standard deviation scores (SDS) increased, from -2.87 before treatment to +3.39 on rhGH, and mean height increased from -3.1 to -2.4 SDS. Serum urea concentrations decreased in most patients during the first month of growth hormone treatment from a mean of 20.0 +/- 7.7 mmol/L to 14.8 +/- 5.8 mmol/L (P = 0.006). The serum urea then returned to pretreatment levels over the next few months. In the 12 months before treatment with growth hormone, mean creatinine clearance decreased from 19.3 mL/min per 1.73 m2 to 16.7 mL/min per 1.73 m2. In the next 12 months on rhGH mean creatinine clearance decreased further to 13.5 mL/min per 1.73 m2. Therefore the rate of deterioration of renal function was unaffected during treatment with growth hormone. Initial treatment with rhGH is associated with decrease in serum urea concentrations in children with CRF, probably mediated by stimulation of anabolic incorporation of dietary nitrogen into body protein.(ABSTRACT TRUNCATED AT 250 WORDS)

A well-known method for sampling AC is to use a meter designed with split-core transformer. The latter is a simple device consisting of a coil that has been opened and hinged such that the coil may be placed around a conductor and closed such that the AC in the conductor will induce a secondary current in the coil that can then be detected and displayed by the meter without having to open the conductor. Our lab is experimenting with this type of instrument for smart grid device development and it was found that short of simulation and/or in situ fieldwork, we were unable to adequately model a high voltage transmission line in the lab to suit our purpose. This paper describes a novel device with which to conduct such experiments that is easily fabricated from locally available materials.

Collagen studies in newborn rat kidneys with incomplete ureteric obstruction. Collagen studies in newborn rats with incomplete ureteric obstruction were performed to describe and quantify changes in collagen deposition resulting from urinary tract obstruction at an early developmental age. Incomplete ureteric obstruction was created in three-day-old rats by placing the left ureter in a tunnel formed by the psoas muscle, and sham-operated controls underwent a laparotomy. The rats were sacrificed at 10, 17, 24 or 31 days. Collagen types I, III, IV, and V were localized by indirect immunofluorescence microscopy, the total collagen content of the kidney was quantitated using hydroxyproline analysis, and collagen types I and III were quantitated using cyanogen bromide (CNBr) peptide analysis. Increased immunofluorescent staining for all of the collagens was found in the diffusely widened medullary interstitium of the obstructed kidney, and more focally in the cortical interstitium. Collagen types I, III and V, but not collagen type IV, were also found in bands in the interstitium at the junction of the cortex with the medulla. Increased staining for collagen type IV was found in thickened and tortuous tubular basement membranes (TBM) of the obstructed kidneys. The total collagen content of the obstructed kidney was significantly increased compared to the amounts in both the contralateral kidneys and in the kidneys from sham-operated controls at 24 and 31 days of age (P < 0.01 in each case, Wilcoxon matched pairs rank sum test and Mann Whitney U-test, respectively). The amount of collagen in the kidneys correlated with the degree of hydronephrosis (Spearman correlation test, r = 0.78, P < 0.02). CNBr peptide analysis demonstrated that over 50% of the collagen in the normal neonatal rat kidney was collagen type I and approximately 25% was collagen type III. In the obstructed kidneys most of the collagen was also collagen type I and collagen type III, although the proportion of total collagen comprised by these collagen types was decreased compared with the controls. The amount of collagen type III in the contralateral kidneys was reduced compared to that in the controls. Thus, the neonatal renal response to obstruction resulted in increased amounts of a range of collagens in the interstitium and TBM, and the extent of this response was partially related to the degree of hydronephrosis.

A number of automated reasoning systems find their basis in process control engineering. These programs are often model-based and use individual frames to represent component functionality. This representation scheme allows the process system to be dynamically monitored and controlled as the reasoning system need only simulate the behavior of the modeled system while comparing its behavior to real-time data. The knowledge acquisition task required for the construction of knowledge bases for these systems is formidable because of the necessity of accurately modeling hundreds of physical devices. We discuss a novel approach to the capture of this component knowledge entitled automated knowledge generation (AKG) that utilizes constraint mechanisms predicated on physical behavior of devices for the propagation of truth through the component model base. A basic objective has been to construct a complete knowledge base for a model-based reasoning system from information that resides in computer-aided design (CAD) databases. If CAD has been used in the design of a process control system, then structural information relating the components will be available and can be utilized for the knowledge acquisition function. Relaxation labeling is the constraint-satisfaction method used to resolve the functionality of the network of components. It is shown that the relaxation algorithm used is superior to simple translation schemes.

In the past decade, the use of control and diagnostic reasoning systems in different areas of government, industry, and university operations has increased. A great number of these systems find their basis in engineering, specifically in process control. The majority of the time devoted to the development of these systems is spent in the areas of Knowledge Engineering (KE) and Knowledge Acquisition (KA). Extensive research for the development of systems that perform the KE task is under way. This article presents an approach toward automatic knowledge acquisition. The objective of this research was to construct a complete knowledge base for a diagnostic and control reasoning system from information that resides in Computer Aided Design (CAD) databases. This work will decrease the amount of time spent in the manual generation of knowledge bases for diagnostic reasoning systems, ft will also enable the creation of more reliable knowledge bases since less hand coding is required.

Two cases of anti-neutrophil cytoplasmic antibody (ANCA)-associated necrotizing and crescentic glomerulonephritis are reported. A 12-year-old girl and a 10-year-old boy presented with polyarthritis, anaemia, haematuria, proteinuria, impaired renal function, anorexia, nausea, marked loss of weight and lethargy. The boy also had a vasculitic rash and anterior uveitis. Both children had diffuse cytoplasmic ANCA identified by indirect immunofluorescence and confirmed by specific enzyme-linked immunosorbent assay. Renal biopsies showed severe focal and segmental necrotizing glomerulonephritis with 100% crescents. They were treated with plasma exchange, prednisolone, cyclophosphamide and heparin. Within 1 month of commencing treatment, both had normal serum creatinine concentrations and ANCA was not detectable. Renal biopsies 6 weeks following commencement of treatment revealed quiescent disease, although up to 40% of glomeruli were sclerosed or had fibrous crescents. Following cessation of cyclophosphamide and heparin after 7 months and reduction in steroid dose, a biopsy at 10 months in the boy revealed quiescent disease, but the girl had recurrent disease associated with reappearance of a low titre of ANCA and small cellular crescents in 20% of the glomeruli. These cases reflect the potential usefulness of ANCA determination for categorizing paediatric patients, helping in the selection of therapy and as a possible marker of disease activity, similar to the experience in adults.

OBJECTIVE To determine the outcome of patients with end-stage chronic renal failure treated by live donor renal transplantation at the Royal Melbourne Hospital and Royal Children's Hospital between 1973 and 1991, during which time two distinct immunosuppressive regimens were used. DESIGN Data about live donor renal transplant recipients were retrieved from the Australian and New Zealand Dialysis and Transplantation Association Registry, to which we have submitted data on all transplant recipients at six monthly intervals since the commencement of our dialysis and transplant programs. PATIENTS Seventy-two patients with chronic renal failure who received live donor renal transplants during the 19 years from February 1973 to February 1992 were included. MAIN OUTCOME MEASURES Patient survival, transplant survival, transplant function, change in prednisolone requirements, and duration of hospital stay. RESULTS The first 32 patients were treated with immunosuppressive regimens based on combinations of prednisolone and azathioprine ("dual therapy"), while the next 40 patients were treated with combinations of cyclosporin, prednisolone and azathioprine ("triple therapy"). Survival of patients in each group five years after transplantation was 97%. Actuarial graft survival at 5, 10 and 15 years in the dual therapy group was 58%, 52% and 47%, compared with a 5-year actuarial graft survival in the triple therapy group of 96%. There was no statistically significant difference in renal transplant function between the two groups within the first 6 years after transplantation. Twelve of 26 patients (46%) treated initially with triple therapy were able to stop treatment with prednisolone within 12 months of transplantation. Median hospital stay was 12 (range, 6-35) days during the period 1973-1985 and 8 (range, 5-20) days for the 1985-1992 period. CONCLUSION Live donor renal transplantation has provided a highly satisfactory means of treating patients with end-stage chronic renal failure in the short and long term. Our recent experience indicates that excellent patient and graft survival and adequate renal function can be achieved by treating live donor renal transplant recipients with a triple immunosuppressive regimen of low dose cyclosporin, prednisolone and azathioprine.

A substantial amount of work has recently been completed at the University of Central Florida in the development of an Artificial Neural Network (ANN) simulation environment that overcomes traditional implementation problems normally associated with these types of programs. Researchers addressing the development and application of ANN systems seek modifiability, expansibility and platform independence. Our system allows for these elements as well as parallel execution when a parallel hardware is available. This is accomplished by use of object-oriented programming and a Computer Aided Software Engineering (CASE) approach to the development environment that allows the user to modify the software describing the ANN model without understanding of the overall implementation details. A sophisticated Graphical User Interface (GUI) is provided to allow rapid construction and evaluation of complex large-scale neural models.

Visual display systems have become so advanced with available options, it is difficult to decide which type of system is needed. Traditionally, the choice has been to select the system with the greatest level of functional and physical fidelity that can be procured. While most would assume that more realism results in better training and performance, research (Dwyer, 1972; Marsh, 1983; Richey, 1986) suggests otherwise. Realism in a display system may serve to be more distracting than helpful, depending upon the training objective. The initial intent of this project was to locate any and all information pertaining to visual display characteristics as they relate to human visual functions or to visual training requirements. A selected literature search was conducted to locate relevant information, data bases or taxonomies that relate the above information. No current taxonomy of this kind was located; therefore, the efforts of the project turned in the direction of formulating a taxonomic structure based on information derived from various disciplines such as instructional technology, human psychology, and computer engineering. General guidelines only, with no specific information, pertaining to the selection of visual media for given situations were found in the instructional technology literature. Based on those guidelines, four general types of presentation media were selected: alphanumerics, 2-dimensional graphics, 3-dimensional graphics, and scene quality. Next, display specifications for these presentations were identified through the aid of engineering and vendor-provided design parameters. Finally, human limitations were applied and psychophysical transformations allowed the determination of final display descriptions.

Sirolimus is an immunosuppressive agent that offers potentially significant benefits for young transplant patients facing life-long treatment. Its action of reducing cell proliferation may reduce the risk of chronic allograft nephropathy and posttransplant neoplasia. Twenty-nine children were converted from calcineurin inhibitors to sirolimus after renal transplantation and followed for a minimum of 12 months. Glomerular filtration increased transiently in those converted before 12 months after transplantation but not in those converted later, when chronic histological changes had developed. Mild acute rejection occurred after conversion in 10%, and side effects led to cessation of sirolimus in 31%. Anemia occurred in 55% of patients and responded well to darbepoetin. Most side effects (anemia, hypercholesterolemia, mouth ulcers, and myalgias) became less severe with time. The number of antihypertensive drugs required decreased significantly on sirolimus. Although side effects are frequent on sirolimus, in the majority of children, they are mild enough to allow the patient to continue taking the drug, and for these children the long-term benefits are potentially valuable.

Summary form only given.The world is currently witnessing the arrival of a new domain in telecommunications, that of network and media convergence. This new field was motivated by the desire to provide a unified interface capable of supporting various services across the many types of delivery networks that are available. This has resulted in a rush to develop and implement new standards and protocols that can support a multiplicity of media services such as the "Triple Play" (voice, data and video), and the "Quadruple Play" (voice, data, video and mobility). Among the emerging standards is the IP Multimedia Subsystem (IMS) that is an overlay control subsystem across heterogeneous access networks. IMS will enable fixed and mobile convergence and support service mobility. On the practical side, an intense competition is underway among fixed and mobile network operators where each is fighting to be the leader in providing fixed-mobile convergence in the least amount of time. Concurrently, another competition related to application convergence is gathering momentum among Internet Service Providers and Content Providers to win customer ownership. One of the other important components in the convergence realm is the need for adopting security techniques and policies that ensure confidentiality, privacy, anonymity, availability and accountability. Clearly, the above activities cannot be sustained and enhanced without developing an appropriate regulatory framework that defines the roles, rights and responsibilities of all involved parties. In this talk, many crucial issues underlying network and media convergence are identified. We also examine current activities and track future trends that will help us grasp the bigger picture of this new and exciting realm - a development that is expected to shape the way we live for many years to come.

Image reconstruction from the measurements of the image Fourier transform magnitude remains an important and difficult problem. Among all the approaches developed to solve this problem, the iterative transform algorithms are currently the most efficient. However, these algorithms suffer from major drawbacks that limit their practical application. We introduce a wavelet adaptation of the general iterative algorithm that can significantly improve the performance of the algorithm while dramatically reducing its computational complexity.

A proposed system for a visual tracker is presented that relies on information developed from previous tracking scenarios stored in a knowledge base to enhance tracking performance. The system is comprised of a centroid tracker front end that supplies segmented image features to a data reduction algorithm and subsequently to a track processor operating under one of two modes, learn or track. While in learn mode, a human operator provides identification cues for membership in a long-term storage relation within a knowledge base. In track mode the system operates autonomously with a cognitive processing algorithm replacing the human operator. The autonomous system functions as a correlation tracker by comparing processed input to data that was stored in the knowledge base during learn mode. Results determined from the classification generate tracker directives that either enhance the current track or cause the tracker to search for alternate targets based on a global target tracking list.

This study examined how often children with persistent familial hematuria were from families where hematuria segregated with the known genetic locus for the condition known as benign familial hematuria or thin basement membrane nephropathy (TBMN) at COL4A3/COL4A4. Twenty-one unrelated children with persistent familial hematuria as well as their families were studied for segregation of hematuria with haplotypes at the COL4A3/COL4A4 locus for benign familial hematuria and at the COL4A5 locus for X-linked Alport syndrome. Eight families (38%) had hematuria that segregated with COL4A3/COL4A4, and four (19%) had hematuria that segregated with COL4A5. At most, eight of the other nine families could be explained by disease at the COL4A3/COL4A4 locus if de novo mutations, non-penetrant hematuria or coincidental hematuria in unaffected family members was present individually or in combination. This study confirms that persistent familial hematuria is not always linked to COL4A3/COL4A4 (or COL4A5) and suggests the possibility of a further genetic locus for benign familial hematuria. This study also highlights the risk of excluding X-linked Alport syndrome on the basis of the absence of a family history or of kidney failure.

Treatment of children with steroid-dependent nephrotic syndrome (SDNS) continues to be a challenge when relapses recur after treatment with cyclophosphamide and side effects or non-compliance make steroids and cyclosporin unsatisfactory. We treated 12 patients with intravenous vincristine for SDNS in a regime of 1-1.5 mg/m2 weekly for 4 weeks then monthly for 4 months. Four of the 5 patients in relapse when commencing vincristine remitted within 2 doses. Comparing relapse frequency in the 12 months before and after vincristine, there was a reduction from 4 to 1.5 (p=0.004) relapses per year. Median sustained remission was 5 months, but 1 frequently relapsing patient remains in remission 4 years after vincristine. Vincristine was also successfully used in 1 or 2 doses at weekly intervals for subsequent relapses in 5 patients. Side effects were minimal in most cases. Abdominal pain occurred in 2 patients who commenced vincristine at 1.5 mg/m2, but resolved when continued at 1 mg/m2. We felt vincristine had a role in a subset of children with challenging SDNS administered as 1 mg/m2 weekly for 4 weeks then 1.5 mg/m2 monthly for 4 months. Vincristine allowed steroid- and cyclosporin-sparing, contributed to long-term remission in some patients, and was especially valuable in children with poor compliance with oral medication. Many patients expressed a preference for a few doses of vincristine rather than a standard course of oral prednisolone or cyclosporin.

Kimura disease is a rare inflammatory condition of unknown aetiology. It typically presents in young Asian males with the triad of non-tender subcutaneous swellings in the head and neck region, peripheral eosinophilia and raised serum IgE. About 16% of cases have associated renal disease. We present the case of a 10-year-old boy with a past history of steroid responsive, frequently relapsing nephrotic syndrome who developed a right submandibular swelling and eosinophilia. Kimura disease was diagnosed on the basis of clinical and histological findings. The condition recurred during relapses of nephrotic syndrome. Because of poor adherence with oral medication, our patient was treated with intravenous vincristine with synchronous remissions of his nephrotic syndrome and Kimura swellings on each occasion.

Several disorders of hypomagnesaemia of hetary renal origin are now recognised. The cases of two sisters from a consanguineous marriage with the syndrome of renal magnesium wasting, hypercalciuria and nephrocalcinosis are presented. Pathological examination of the heterozygous parental kidneys revealed mild focal interstitial fibrosis. This condition is a previously unreported cause of end-stage renal failure in chilhhood, and this report suggests that transplantation from heterozygous parental donors can be successfully undertaken without recurrence currence of the syndrome.

A system is described that performs automated knowledge generation (AKG) using structural databases to create semantic knowledge bases. The approach, borrowed from machine vision, uses relaxation labeling to propagate constraints through the system. A prototype system has been developed which accesses an Intergraph CAD database, 'processes' the information contained therein, and generates a frame-based knowledge base usable by NASA's Knowledge-based Autonomous Test Engineer (KATE) diagnostic system. The authors present a summary of work to date and discuss some of the obstacles found by the research group during the development of the AKG system. >

A system that converts the computer-aided design (CAD) database description of a process control system into a frame-oriented knowledge base for a diagnostic expert control system is described. The target expert system for the automated knowledge generation is NASA's Knowledge-Based Autonomous Test Engineer (KATE), developed to assist in the monitoring and control of Space Shuttle ground support systems. KATE retains the structure of the system it has knowledge about in its frame representations and derives understanding of the target system from intercomponent relationship knowledge held within those frames. A CAD database generated for a particular process control system contains all the structural information required to reconstruct the system, but little or no functional data. A functional description can be inferred in some cases from the CAD data; however, the complexity of such a system for a domain as large as process control is extensive. The construction and operation of an automated knowledge generation software system that performs the conversion from CAD database to knowledge base are discussed. >

PURPOSE: To determine the association between vesicoureteral reflux (VUR) and the presence of acute pyelonephritis in children with urinary tract infections. MATERIALS AND METHODS: The authors studied 150 consecutive patients less than 5 years of age with their first proved urinary tract infection. All patients underwent renal cortical scintigraphy (with technetium-99m dimercaptosuccinic acid or Tc-99m gluconate) and voiding cystourethrography (VCUG) to identify the presence of cortical defects and VUR, respectively. RESULTS: Of 300 kidneys, 88 (29.3%) had a cortical defect at scintigraphy. Fifty-four of the 88 patients (61%) did not have VUR demonstrated at VCUG. Conversely, 72 of the 300 kidneys (24%) had VUR; of these, 38 (53%) had no cortical defect. The sensitivity of VCUG in helping predict a defect was 38.6%, and the specificity was 82.1%. CONCLUSION: VUR (as shown by VCUG) and renal cortical scintigraphic defects frequently occur independently of each other. Renal cortical scintigraphy may be a mo...

An approach to the autonomous acquisition of world knowledge is presented. Based on the theory that biological cognizance is essentially a Gestalt awareness of the world, our research attempts to develop a similar awareness using an associative memory. This associative memory receives inputs from several self-organizing feature maps which identify objects in particular parts of an image. Spatial relationships of objects in the image are reflected in the relationship of the feature maps to each other, so the associative memory records both identity and spatial information of objects. To this visual memory is added the memory of the viewer's internal status, in this case an estimate of position. Together, these associative memories provide a view-field model of location awareness similar to that originally presented by D. Zipser (1986). In keeping with the Gestalt approach taken here, the grandmother cell approach of the earlier work has been replaced by the use of distributed representations. View-fields are identified as a pattern of activity across a number of nodes. It is believed that this distributed approach will permit greater generalization on the part of the viewer and provide a larger memory capacity than can be achieved otherwise. >

Recent studies have demonstrated that both congenital hypoplasia and acquired scarring are involved in the parenchymal lesions associated with reflux nephropathy. Medical therapy can prevent symptomatic infection. While there is no proof that either medical or antireflux surgery prevents acquired scarring, paradoxically there is evidence that surgery adds no benefit to medical therapy, and that the results of medical therapy and surgical therapy are similar in children with isolated severe reflux. The group at most severe risk of renal scarring is infants and the effects of medical and surgical therapy in preventing acquired renal injury in this group have not been sufficiently investigated. On the basis of this information it has been our practice to maintain urine sterility using continuous antibiotic prophylaxis throughout infancy and early childhood. Following the development of reliable urine toilet habit and the ability to collect midstream urine specimens, antibiotics are given according to the frequency of urine infection, and weekly testing of morning urine with nitrite strips at home is used for early detection of infection and prevention of symptomatic infection. Antireflux surgery is mandatory for those children with complicated VUR (such as urinary tract obstruction) and should otherwise be reserved for those having persistent breakthrough infections in infancy and early childhood.

Background. Acute pyelonephritis is distinguished from renal scarring using repeat cortical scintigraphy. The defects of acute pyelonephritis resolve, while those of scars persist. Objective. To determine the duration of reversible cortical defects following acute pyelonephritis and the time interval required to differentiate infection from scars. Materials and methods. An observational prospective study of 193 children (386 kidneys) aged less than 5 years following their first proven urinary tract infection (UTI). Renal cortical scintigraphic defects were detected in 112 (29%) kidneys within 15 days of diagnosis. Of these, 95 underwent repeat renal cortical scans 2 years after the UTI, including 50 with additional scans performed within 2–6 months of infection. Results. Of the 50 kidneys undergoing a second renal cortical scan within 2–6 months of the first UTI, 22 (44%) had persistent defects. A third scan was performed on 17 (77%) kidneys after 2 years, by which time defects had resolved in another 8 (47%) kidneys. The predictive value of defects detected within 2–6 months of UTI representing scars is 53% (95% CI 28, 77). Overall, nine (18%) kidneys with initial renal cortical abnormalities had permanent defects. In the 45 kidneys undergoing a second cortical scan more than 6 months after the UTI, 11 (24%) had persistent defects. None of the 95 kidneys undergoing serial scans developed new or larger defects. Conclusions. Renal scars may not be reliably diagnosed by cortical scintigraphy performed within 6 months of UTI because the inflammatory lesions may not have fully resolved.

An interesting problem arises in multi platform-multisensor information fusion system when sources disagree on the classification or identity of an unknown entity. If there is disagreement, the ideal situation ins a high level of confidence form a single source with complete disagreement in the remaining sources. This is not always the case and situations may arise where the winner is only successful by a small margin and there is collective disagreement amongst the losing sources. This paper describes a new terminology, disfusion, which is used for the characterization of disagreement between information sources and can enhance the final conclusion of a fusion system.

Many approaches to target recognition on SAR images employ model-based techniques. These systems incorporate computationally intensive operations such as large database probing or complex 3D renderings that are used to produce simulations that are compared against unknown targets. These operations would achieve a significant improvement in speed performance if the target poses were known in advance. A study that addresses the problem of estimating the poses of vehicles in SAR images is reported in this paper. A pose estimation algorithm suite is proposed that is based on a set of partially independent criteria. A statistical analysis of the performance obtained by employing the established criteria, both individually and in combination, is also conducted and the results are comparatively discussed.

A model-based system employing a computationally intelligent search strategy has been developed for classifying military vehicles in SAR imagery. The system combines pose detection, Evolutionary Programming (EP) methods, and Geometric Hashing (GH). The design is based on an information filtering process that progressively narrows the scope of the problem space while maximizing for success. While the current system has been trained to identify 12 military vehicles, the architecture is extensible to additional vehicle types.