cssi/SciSciGPT-SciSciNet huggingface dataset:
Combining maps and street level images for building height and facade estimation

We propose a method that integrates two widely available data sources, building footprints from 2D maps and street level images, to derive valuable information that is generally difficult to acquire --- building heights and building facade masks in images. Building footprints are elevated in world coordinates and projected onto images. Building heights are estimated by scoring projected footprints based on their alignment with building features in images. Building footprints with estimated heights can be converted to simple 3D building models, which are projected back to images to identify buildings. In this procedure, accurate camera projections are critical. However, camera position errors inherited from external sensors commonly exist, which adversely affect results. We derive a solution to precisely locate cameras on maps using correspondence between image features and building footprints. Experiments on real-world datasets show the promise of our method.
Diffusion in Networks and the Unexpected Virtue of Burstiness

Whether an idea, information, disease, or innovation diffuses throughout a society depends not only on the structure of the network of interactions, but also on the timing of those interactions. Recent studies have shown that diffusion can fail on a network in which people are only active in "bursts," active for a while and then silent for a while, but diffusion could succeed on the same network if people were active in a more random Poisson manner. Those studies generally consider models in which nodes are active according to the same random timing process and then ask which timing is optimal. In reality, people differ widely in their activity patterns -- some are bursty and others are not. We model diffusion on networks in which agents differ in their activity patterns. We show that bursty behavior does not always hurt the diffusion, and in fact having some (but not all) of the population be bursty significantly helps diffusion. We prove that maximizing diffusion requires heterogeneous activity patterns across agents, and the overall maximizing pattern of agents' activity times does not involve any Poisson behavior.
Topology and Geometry of Half-Rectified Network Optimization

The loss surface of deep neural networks has recently attracted interest in the optimization and machine learning communities as a prime example of high-dimensional non-convex problem. Some insights were recently gained using spin glass models and mean-field approximations, but at the expense of strongly simplifying the nonlinear nature of the model. In this work, we do not make any such assumption and study conditions on the data distribution and model architecture that prevent the existence of bad local minima. Our theoretical work quantifies and formalizes two important \emph{folklore} facts: (i) the landscape of deep linear networks has a radically different topology from that of deep half-rectified ones, and (ii) that the energy landscape in the non-linear case is fundamentally controlled by the interplay between the smoothness of the data distribution and model over-parametrization. Our main theoretical contribution is to prove that half-rectified single layer networks are asymptotically connected, and we provide explicit bounds that reveal the aforementioned interplay. The conditioning of gradient descent is the next challenge we address. We study this question through the geometry of the level sets, and we introduce an algorithm to efficiently estimate the regularity of such sets on large-scale networks. Our empirical results show that these level sets remain connected throughout all the learning phase, suggesting a near convex behavior, but they become exponentially more curvy as the energy level decays, in accordance to what is observed in practice with very low curvature attractors.
Predicting the production rates of cosmogenic nuclides

Abstract The determination and some uses of production rates of cosmogenic nuclides are reviewed. Emphasis is on work done since 1993 for long-lived cosmogenic radionuclides in extraterrestrial matter. Several Monte Carlo computer codes are being used to numerically simulate the interactions and transport of cosmic-ray particles. Thin- and thick-target irradiations have been done with protons to determine reaction cross sections and to experimentally simulate cosmic-ray bombardments. Cross sections for some neutron-induced reactions are being measured or inferred from thick-target irradiations. Some other works involving cosmogenic-nuclide production rates are discussed.
Mass Spectrometry with Cryogenic Detectors

Abstract Cryogenic detectors have recently been applied for the first time as ion detectors in time-of-flight mass spectrometry (TOF-MS). Because of their energy sensitivity cryogenic detectors are expected to have near 100% efficiency even for very large, slow-moving molecules, in contrast to microchannel plates whose efficiency drops considerably at large mass. Thus, cryogenic detectors could contribute to extending the mass range accessible by TOF-MS and help improving detection limits. In addition, the energy resolution provided by cryogenic detectors can be used for charge discrimination and studies of ion fragmentation, ion–detector interaction, and internal energies of large molecular ions. Cryogenic detectors could therefore prove to be a valuable diagnostic tool in TOF-MS. Here I summarize the results of recent demonstration experiments.
Interactions and design rules for assembly of porous colloidal mesophases

Porous mesophases, where well-defined particle-depleted ‘void’ spaces are present within a particle-rich background fluid, can be self-assembled from colloidal particles interacting via isotropic pair interactions with competing attractions and repulsions. While such structures could be of wide interest for technological applications (e.g., filtration, catalysis, absorption, etc.), relatively few studies have investigated the interactions that lead to these morphologies and how they compare to those that produce other micro-phase-separated structures, such as clusters. In this work, we use inverse methods of statistical mechanics to design model isotropic pair potentials that form porous mesophases. We characterize the resulting porous structures, correlating features of the pair potential with the targeted pore size and the particle packing fraction. The former is primarily encoded by the amplitude and range of the repulsive barrier of the designed pair potential and the latter by the attractive well depth. We observe a trade-off with respect to the packing fraction of the targeted morphology: greater values support more spherical and monodisperse pores that themselves organize into periodic structures, while lower values yield more mobile pores that do not assemble into ordered structures but remain stable over a larger range of packing fraction. We conclude by commenting on the limitations of targeting a specific pore diameter within the present inverse design approach as well as by describing future directions to overcome these limitations.
Supply chain network capacity competition with outsourcing: a variational equilibrium framework

This paper develops a supply chain network game theory framework with multiple manufacturers/producers, with multiple manufacturing plants, who own distribution centers and distribute their products, which are distinguished by brands, to demand markets, while maximizing profits and competing noncooperatively. The manufacturers also may avail themselves of external distribution centers for storing their products and freight service provision. The manufacturers have capacities associated with their supply chain network links and the external distribution centers also have capacitated storage and distribution capacities for their links, which are shared among the manufacturers and competed for. We utilize a special case of the Generalized Nash Equilibrium problem, known as a variational equilibrium, in order to formulate and solve the problem. A case study on apple farmers in Massachusetts is provided with various scenarios, including a supply chain disruption, to illustrate the modeling and methodological framework as well as the potential benefits of outsourcing in this sector.
bariatric Surgery Prior to Index Screening Colonoscopy Is Associated With a Decreased Rate of Colorectal Adenomas in Obese Individuals

Bariatric Surgery Prior to Index Screening Colonoscopy Is Associated With a Decreased Rate of Colorectal Adenomas in Obese Individuals
Illusory Gains from Chile's Targeted School Voucher Experiment

In 2008, Chile implemented a targeted voucher program that increased voucher values for disadvantaged students at participating schools by approximately 50%. Although disadvantaged students made substantial fourth grade test score gains that other studies have attributed to the program, our analysis raises serious doubts that the program had a substantial effect on cognitive skills. First, there was only a minor reduction in class size and little evidence of increases in any inputs. An audit showed that many schools were not using additional revenues for permitted expenditures, and estimates that exploit a discontinuity in the revenues allocated to schools show no evidence of positive effects of allocated funds on achievement growth. In addition, there is limited evidence of competitive or incentive effects on school quality or that disadvantaged students transitioned to higher quality schools. The much smaller gains made by disadvantaged students in low-stakes eighth grade test scores along with an increased rate of missing scores on fourth grade tests is consistent with extensive strategic behavior by schools. In contrast, increases in parental education and income among disadvantaged children indicate a primary role for improvements in family circumstances of tested students in explaining the meaningful decline in the achievement gap.
Computational Thinking Guiding Change in Online Education

As a result of instant access to data, information and knowledge anywhere, anytime, today’s students have rapidly acquired educational opportunities. Online education continues to grow at a pace much faster than face to face enrollments. There is a need for faculty development and training who can teach with technology, design and develop online courses in order to meet the increasing student demand. Faculty barriers to online education include loss of interpersonal student relationships, technology challenges, pedagogical concerns, institutional policy problems and unidentified support or compensation for all associated processes. At the crossroads of problem identification, strategy, and adoption of innovation, Computation Thinking (CT) offers a logical, exploratory, expandable and collaborative way of solving a complex problem in a state of change. This paper aims to summarize and synthesize the literature on both CT and faculty barriers to adoption of online education. A further aim is to offer suggestions for collaborative faculty design and development opportunities in exploring their own experience with online education using CT as a framework for problem-solving. DOI: 10.2458/azu_itet_v4i2_quinn
Impurity Diffusion in Highly-Ordered Intermetallic Compounds Studied by Nuclear Quadrupole Interactions

Diffusion of impurity atoms depends on the sublattices occupied, active diffusion mechanisms, and jump frequencies to neighboring sites. The method of perturbed angular correlation of gamma rays (PAC) has been applied over the past decade to study impurity diffusion through measurement of nuclear quadrupole interactions (NQI) at nuclei of 111In/Cd probe atoms. Extensive measurements have been made on highly-ordered compounds having the L12 crystal structure, including In3R, Sn3R, Ga3R, Al3R and Pd3R phases (R= rare-earth element). Measurements in thermal equilibrium at high temperature served to determine lattice locations of 111In parent probe-atoms, through characteristic NQIs, and to measure diffusional jump-frequencies of 111Cd daughter probe-atoms, through relaxation of the NQI. This paper summarizes results of the jump-frequency measurements and relates them to the conventional diffusivity that can be determined, for example, from penetration profiles of tracer species. In spite of chemical similarities of the series of rare-earth phases studied, remarkably large variations in jump frequencies have been observed especially along series of In3R and Pd3R phases. Most phases appear as “line compounds” in binary phase diagrams, but large differences in site-preferences and jump-frequencies were observed for samples prepared to have the opposing limiting phase boundary compositions. Comparisons of jump-frequencies measured at opposing boundary compositions can give insight into the predominant microscopic diffusional mechanisms of the impurity. A change in diffusion mechanism was proposed in 2009 to explain jump-frequency systematics for In3R phases. An alternative explanation is proposed in the present paper based on site-preferences of 111Cd daughter probes newly observed along the parallel Pd3R series. The diffusivity can be expressed as the product of a jump-frequency such as measured in these studies and a correlation factor for diffusion that depends on the diffusion mechanism. The correlation factor can be modeled for the L12 structure and diffusion sublattice of interest using a five-frequency model originally proposed for metals. Although the correlation factor is an essential parameter for the diffusion of impurities, it has never been measured. It is suggested that values of the correlation factor can be determined feasibly by combining results of jump-frequency measurements such as the present ones with diffusivity measurements made for the same host-impurity systems.
Oxidized Derivatives of Linoleic Acid in Pediatric Metabolic Syndrome: Is Their Pathogenic Role Modulated by the Genetic Background and the Gut Microbiota?

Abstract We tested whether oxidized linoleic acid metabolites (OXLAM) are associated with pediatric metabolic syndrome (MetS) and a proatherogenic lipoprotein profile in 122 obese adolescents. Furthermore, we examined whether genetic and metagenomic factors can modulate plasma OXLAM concentrations by genotyping the fatty acid desaturase 1/2 (FADS) gene and by characterizing the gut microbiota. Subjects with MetS (n = 50) showed higher concentrations of 9- and 13-oxo-octadecadienoic acid (9- and 13-oxo-ODE) than subjects without MetS (n = 72). Both metabolites were associated with an adverse lipoprotein profile that was characterized by elevated very small-dense low-density lipoprotein (p < 0.005) and large very low-density lipoprotein particles (p = 0.01). Plasma 9- and 13-oxo-ODE were higher in subjects carrying the haplotype AA of the FADS gene cluster (p = 0.030 and p = 0.048, respectively). Furthermore, the reduced gut bacterial load was associated with higher 9-oxo-ODE concentrations (p = 0.035). Thi...
Versatile strain-tuning of modulated long-period magnetic structures

We report a detailed small-angle neutron scattering (SANS) study of the skyrmion lattice phase of MnSi under compressive and tensile strain. In particular, we demonstrate that tensile strain applied to the skyrmion lattice plane, perpendicular to the magnetic field, acts to destabilize the skyrmion lattice phase. This experiment was enabled by our development of a versatile strain cell, unique in its ability to select the application of either tensile or compressive strain in-situ by using two independent helium-actuated copper pressure transducers, whose design has been optimized for magnetic SANS on modulated long-period magnetic structures and vortex lattices, and is compact enough to fit in common sample environments such as cryostats and superconducting magnets.
The Effects of "Positive Action" on Preschoolers' Social-Emotional Competence and Health Behaviors.

Children from low-income families are at greater risk for poor social–emotional development and physical health and may be in need of intervention. This study examined the extent to which the Positive Action (PA) preschool lessons improved low-income children’s social–emotional competence and health behaviors. Mixed findings emerged with regard to whether the lessons facilitated growth in child outcomes. Results showed positive effects of PA on children’s directly assessed social problem solving skills and their parent-rated social–emotional competence and health behaviors. Unexpectedly, program effects on teacher ratings of social–emotional competence were in the opposite direction. These findings provide preliminary evidence that PA may be effective in promoting positive social–emotional and health behavior outcomes for children, particularly when outcomes are assessed directly and by parents.
A NOVEL TAPERED WEDGE STEM: MULTICENTRE CLINICAL OUTCOMES STUDY

Introduction Cementless tapered wedge stems have shown excellent results over the last decade. Distal potting with inadequate proximal fit, as well as failure to achieve biologic fixation has led to thigh pain, loosening and implant failure. To support a variety of patient morphologies a novel tapered wedge stem was designed with reduced distal morphology, maximizing the proximal contact of the grit blasted surface. The objective of the study was to analyze the clinical outcomes of this stem design. Methods Three hundred and nineteen patients enrolled into prospective, post-market multicenter studies received a novel tapered wedge stem. Clinical and patient-reported outcomes including the Harris Hip Score (HHS), Lower Extremity Activity Scale (LEAS), Short Form 12 (SF12), and Euroqol 5D Score (EQ-5D) were evaluated preoperative through two years postoperative. Results Demographics of the study population include 53.3% male patients with a mean age of 62.4 ± 9.3 years and BMI of 29.8 ± 4.5. To date, there has been one incidence of thigh pain (0.3%) and a 0.63% aseptic revision rate. Kaplan-Meier survivorship analysis for the population at two years postoperative estimated 97.87% with 95% CI (93.98% – 99.25%) survivorship to all cause revision ( Figure 1 ). Statistically significant improvements in pain, function, and quality of life were seen initially at six weeks postoperative and continued through one year in all of the clinical and patient reported outcome measures ( Figure 2 ). Conclusion A novel tapered wedge stem was designed to maximize proximal fit medially and laterally across a variety of patient morphologies. Radiographic studies have shown the stem design has significantly better canal fit compared to older tapered wedge designs. The current study exhibits low incidence of thigh pain and revisions, with improvements in function, pain and quality of life after hip arthroplasty with this tapered wedge stem.
La evolución de las economías en el transcurso del tiempo

La historia economica se ocupa de la evolucion de las economias en el transcurso del tiempo. El objetivo de las investigaciones que se realizan en este campo no es solo aportar alguna luz sobre el pasado economico, sino tambien contribuir a la teoria economica ofreciendo un marco analitico que nos permita comprender los cambios economicos. El instrumento analitico ideal seria una teoria de la dinamica economica que fuera comparable por su precision a la teoria de equilibrio general. En ausencia de una teoria de ese tipo, podemos describir las caracteristicas de las economias pasadas, examinar su comportamiento en determinados momentos y realizar un analisis de estatica comparativa; pero falta una comprension analitica de la manera en que evolucionan las economias con el paso del tiempo
Humanitarian transportation planning: Evaluation of practice-based heuristics and recommendations for improvement

Abstract Transportation bottlenecks are a common and critical problem in humanitarian response. There is a need for better planning and prioritization of vehicles to transport humanitarian aid to affected communities. Optimization approaches have been developed for transportation planning, but adoption has been limited, due in part to the difficulty of implementation. This paper develops the basis for an easily implementable decision support tool by building on current planning practices in the humanitarian sector. We draw on an observational study to describe current planning practices, then develop heuristic algorithms that represent the observed planning processes, and compare their solutions to each other and to those of a mixed-integer linear program. We identify key weaknesses to guide the development of more sophisticated heuristics or optimization models that fit with current planning practices. We also find that a simple practice-driven heuristic performs well when it prioritizes deliveries based on destination priority or distance, and we argue that automating such a heuristic in a decision support tool would maintain the simplicity and transparency to enable implementation in practice, and improve planning by saving time and increasing accuracy and consistency.
Financial Reporting Quality and Dual-Holding of Debt and Equity

I investigate whether the financial reporting quality (FRQ) of a firm influences the propensity of institutional investors to simultaneously hold the firm's debt and equity (i.e., dual-holding). I ...
Learning combinatorial optimization algorithms over graphs

The design of good heuristics or approximation algorithms for NP-hard combinatorial optimization problems often requires significant specialized knowledge and trial-and-error. Can we automate this challenging, tedious process, and learn the algorithms instead? In many real-world applications, it is typically the case that the same optimization problem is solved again and again on a regular basis, maintaining the same problem structure but differing in the data. This provides an opportunity for learning heuristic algorithms that exploit the structure of such recurring problems. In this paper, we propose a unique combination of reinforcement learning and graph embedding to address this challenge. The learned greedy policy behaves like a meta-algorithm that incrementally constructs a solution, and the action is determined by the output of a graph embedding network capturing the current state of the solution. We show that our framework can be applied to a diverse range of optimization problems over graphs, and learns effective algorithms for the Minimum Vertex Cover, Maximum Cut and Traveling Salesman problems.
Intraseasonal sea surface warming in the western Indian Ocean by oceanic equatorial Rossby waves

A novel process is identified whereby equatorial Rossby (ER) waves maintain warm sea surface temperature (SST) anomalies against cooling by processes related to atmospheric convection in the western Indian Ocean. As downwelling ER waves enter the western Indian Ocean, SST anomalies of +0.15 °C develop near 60°E. These SST anomalies are hypothesized to stimulate convective onset of the Madden-Julian oscillation (MJO). The upper ocean warming that manifests in response to downwelling ER waves is examined in a mixed layer heat budget using observational and reanalysis products, respectively. In the heat budget, horizontal advection is the leading contributor to warming, in part due to an equatorial westward jet of 80 cm s-1 associated with downwelling ER waves. When anomalous currents associated with ER waves are removed in the budget, the warm intraseasonal temperature anomaly in the western Indian Ocean is eliminated in observations and reduced by 55% in reanalysis.
A generalized two-fluid picture of non-driven collisionless reconnection and its relation to whistler waves

A generalized, intuitive two-fluid picture of 2D non-driven collisionless magnetic reconnection is described using results from a full-3D numerical simulation. The relevant two-fluid equations simplify to the condition that the flux associated with canonical circulation Q=me∇×ue+qeB is perfectly frozen into the electron fluid. In the reconnection geometry, flux tubes defined by Q are convected with the central electron current, effectively stretching the tubes and increasing the magnitude of Q exponentially. This, coupled with the fact that Q is a sum of two quantities, explains how the magnetic fields in the reconnection region reconnect and give rise to strong electron acceleration. The Q motion provides an interpretation for other phenomena as well, such as spiked central electron current filaments. The simulated reconnection rate was found to agree with a previous analytical calculation having the same geometry. Energy analysis shows that the magnetic energy is converted and propagated mainly in the f...
Is There a Case for Strict Liability

In this short paper, I shall answer the title’s question first in the context of criminal law and then in the context of tort law. In that latter section, I shall also mention in passing contractual and other forms of civil liability that are strict, although they will not be my principal focus. My conclusions will be that strict liability is never proper as the basis for retributive punishment; that it is a very crude device for achieving deterrence through nonretributive penalties; and that with respect to tort liability, it is best justified as a means of defining insurance categories.
LoadingZones: leveraging street parking to enable vehicular internet access

Internet connectivity is nowadays an ubiquitous service. However, on the road we obtain access using costly and limited data cellular network subscriptions. This, along with significant network congestion, severely limits network use. Opportunistic access to indoor APs is limited by three factors. First, establishing a link to an AP requires a significant amount of time, and, second, links on the street usually have poor quality. Third, the lifetime of this link is very short in a moving car, due to indoor APs generally covering small areas of the street. Combined, these factors thwart opportunistic use of APs for Internet access. In this paper, we propose a novel approach that leverages the large number of parked cars to separate these three factors and tackle them independently: a parked car can connect to an AP with a link that, despite its poor quality, has a long lifetime. A moving vehicle can instead benefit from the better link with a parked car and use it as a relay. As our experiments show, our approach enables the use of this free, high throughput channel for a number of non time-sensitive applications, thus reducing cost and the load on the cellular network.
Evolinc: A Tool for the Identification and Evolutionary Comparison of Long Intergenic Non-coding RNAs.

Long intergenic non-coding RNAs (lincRNAs) are an abundant and functionally diverse class of eukaryotic transcripts. Reported lincRNA repertoires in mammals vary, but are commonly in the thousands to tens of thousands of transcripts, covering ~90% of the genome. In addition to elucidating function, there is particular interest in understanding the origin and evolution of lincRNAs. Aside from mammals, lincRNA populations have been sparsely sampled, precluding evolutionary analyses focused on their emergence and persistence. Here we present Evolinc, a two-module pipeline designed to facilitate lincRNA discovery and characterize aspects of lincRNA evolution. The first module (Evolinc-I) is a lincRNA identification workflow that also facilitates downstream differential expression analysis and genome browser visualization of identified lincRNAs. The second module (Evolinc-II) is a genomic and transcriptomic comparative analysis workflow that determines the phylogenetic depth to which a lincRNA locus is conserved within a user-defined group of related species. Here we validate lincRNA catalogs generated with Evolinc-I against previously annotated Arabidopsis and human lincRNA data. Evolinc-I recapitulated earlier findings and uncovered an additional 70 Arabidopsis and 43 human lincRNAs. We demonstrate the usefulness of Evolinc-II by examining the evolutionary histories of a public dataset of 5,361 Arabidopsis lincRNAs. We used Evolinc-II to winnow this dataset to 40 lincRNAs conserved across species in Brassicaceae. Finally, we show how Evolinc-II can be used to recover the evolutionary history of a known lincRNA, the human telomerase RNA (TERC). These latter analyses revealed unexpected duplication events as well as the loss and subsequent acquisition of a novel TERC locus in the lineage leading to mice and rats. The Evolinc pipeline is currently integrated in CyVerse’s Discovery Environment and is free for use by researchers.
Efficient purely-dynamic information flow analysis

We present a novel approach for efficiently tracking information flow in a dynamically-typed language such as JavaScript. Our approach is purely dynamic, and it detects problems with implicit paths via a dynamic check that avoids the need for an approximate static analyses while still guaranteeing non-interference. We incorporate this check into an efficient evaluation strategy based on sparse information labeling that leaves information flow labels implicit whenever possible, and introduces explicit labels only for values that migrate between security domains. We present experimental results showing that, on a range of small benchmark programs, sparse labeling provides a substantial (30%-50%) speed-up over universal labeling.
Indicators of conformal field theory: Entanglement entropy and multiple-point correlators

The entanglement entropy (EE) of quantum systems is often used as a test of low-energy descriptions by conformal field theory (CFT). Here we point out that this is not a reliable indicator, as the EE often shows the same behavior even when a CFT description is not correct (as long as the system is asymptotically scale-invariant). We use constraints on the scaling dimension given by the CFT with SU(2) symmetry to provide alternative tests with two- and four-point correlation functions, showing examples for quantum spin models in 1+1 dimensions. In the case of a critical amplitude-product state expressed in the valence-bond basis (where the amplitudes decay as a power law of the bond length and the wave function is the product of all bond amplitudes), we show that even though the EE exhibits the expected CFT behavior, there is no CFT description of this state. We provide numerical tests of the behavior predicted by CFT for the correlation functions in the critical transverse-field Ising chain and the $J\text{\ensuremath{-}}Q$ spin chain, where the conformal structure is well understood. That behavior is not reproduced in the amplitude-product state.
Inequality and Globalization: A Review Essay

As normally measured, "global inequality" is the relative inequality of incomes found among all people in the world no matter where they live. Francois Bourguignon and Branko Milanovic have written insightful and timely books on global inequality, emphasizing the role of globalization. The books are complementary: Milanovic provides an ambitious broad-brush picture, with some intriguing hypotheses on the processes at work; Bourguignon provides a deep and suitably qualified economic analysis. This paper questions the thesis of both books—that globalization has been a major driving force of inequality between or within countries. The paper also questions the robustness of the evidence for declining global inequality, and notes some conceptual limitations of standard measures in capturing the concerns of many observers in the ongoing debates about globalization and the policy responses.
Necessary and Sufficient Conditions for Designing Optimal Feedback Controllers for Linear Dynamical Systems with Multiple Time Delays

Abstract New necessary and sufficient conditions for designing stabilizing optimal feedback controllers for linear systems with multiple time-de1ays are presented. These conditions are natural extensions of the same well-known conditions proposed in 1972 by V. Kucera with respect to linear systems without delay. They are arrived at by using the method of canonical decomposition of Krasovskii, Osipov, Shimanov, Hale, Banks and Manitius. Once the delayed system has been canonically decomposed with respect to its unstable modes, it is shown how simpler conditions, equivalent to Kucera's stabilizability and detectability conditions, may be obtained so that the usual test for complete controllability and complete reconstructibi1ity may be applied. The two matrix pairs involved are given. A brief example illustrates the procedure.
Renal Transplant Dysfunction: MR Evaluation

The results of 45 MR examinations were prospectively compared with the clinical course and biopsy results in 38 renal transplant patients to determine the role of MR in evaluating allograft dysfunction. Twenty-six patients underwent allograft biopsy. In eight patients in whom the biopsy was performed more than 48 hr after MR examination and in 19 patients who did not have a biopsy, the subsequent clinical course was sufficiently diagnostic to determine the specific cause of the transplant dysfunction. Corticomedullary differentiation, graded from 0 to 3, was not helpful in separating rejection (n = 20) from acute tubular necrosis (n = 9), drug toxicity (n = 7), pyelonephritis (n = 2), or normal grafts (n = 7) because of overlap between groups (sensitivity =; 60%, specificity = 60%). In the six patients with two or more MR studies, serial changes in corticomedullary differentiation were not consistent and could not be used to diagnose rejection. When any abnormality of allograft sinus fat, size or shape, or corticomedullary differentiation was considered, the sensitivity for the diagnosis of rejection approached 80%; however, specificity was low (48%). We conclude that MR imaging is not sufficiently accurate to replace transplant biopsy and therefore has a limited role in the evaluation of transplant dysfunction.
Sexually Transmitted Diseases in Sexually Abused Children

Over a 4-year period, 409 cases of suspected sexual abuse of children were reviewed to study sexually transmitted disease (STD). Sexually transmitted disease was identified in 54 (13%) of the 409 children: 46 cases of gonorrhea, six cases of syphilis, four cases of trichomoniasis, and three cases of condyloma acuminata. Nine of the 46 children with cultures positive for gonorrhea did not have a history of discharge. Four of the six children with syphilis also had a gonococcal infection. One child with syphilis had condyloma. Only one child had clinical features of syphilis. Sexually transmitted disease was more likely to be transmitted by an extended family member or a nonfamily member than by a father/stepfather (P less than .001). Laboratory tests that identify sexually transmitted disease may aid in the diagnosis of sexual abuse.
Access to financial services in Zambia

Despite the deep financial sector reforms undertaken in Zambia in the early 1990s, the expected benefits of establishing a market-based banking system has not materialized. In 2005 the banking system continued to be small and underdeveloped. Credit to the private sector by banks represented only 8 percent of GDP in 2005, which is slightly lower than the level registered in 1990. As in the early 1990s, only large corporations and a few small- and medium-size enterprises have access to credit in 2006. Moreover, less than 8 percent of Zambia's adult population had a bank account in 2005. And despite the open door policy to foreign financial institutions, which has been in place since Zambia's independence, only a few new banking products have been introduced by foreign banks to serve the needs of households and firms. This paper analyzes the factors that have prevented the development of a large and inclusive banking system in Zambia and highlights possible actions that may help improve access to finance in Zambia in both the short and long terms.
Histological and Ultrastructural Changes in Rat Kidney after Cryosurgery

Effect of cryoinjury to normal rat kidney was studied at the light and electron microscope level, and characterization of the time course of pathologic changes in kidney tissue after cryosurgery was described from 1 hr up to 14 days after production of a standard cryolesion. Cryoinjury to the kidney resulted in sharply demarcated lesions with minimal inflammatory response during the period of cell destruction and healing by fibrosis. Cellular protein was completely coagulated within 1 hr after cryoinjury, with crystallization of protein and disruption of membranes. Cellular disruption was rapid, and the clearance of cellular debris from the area of injury by macrophage infiltration was accomplished through a quite mild inflammatory reaction. Supporting stromal elements of renal parenchyma remained intact, including collagen tubular framework and basement membranes, and formed the lattice over which fibrosis developed.
Ketoconazole-Induced Increase in Estradiol-Testosterone Ratio: Probable Explanation for Gynecomastia

• Ketoconazole, an antifungal drug, causes gynecomastia in some patients. It also inhibits androgen and glucocorticoid synthesis. In four volunteer male subjects, 600-mg doses of ketoconazole depressed serum testosterone concentrations markedly, but serum estradiol to a much lesser degree. The bound and free percentages of both hormones were not significantly altered. The net result was a significant elevation of the estradiol-testosterone ratio, expressed as either total circulating hormone or free hormone. In five male patients receiving long-term high-dose ketoconazole therapy, the testosterone concentrations fell, but the effect on estradiol was variable. In these patients the estradiol-testosterone ratio was persistently increased. Since gynecomastia appears to be the result of an elevated estradiol-testosterone ratio, the selective hormonal effect demonstrated may explain the side effect of gynecomastia after ketoconazole therapy. (Arch Intern Med1985;145:1429-1431)
Hormone Kinetics After Intramuscular Testosterone Cypionate

There have not been reports analyzing in detail the reproductive hormone changes in hypogonadal men after usual therapeutic injections of testosterone cypionate (TC). In 11 hypogonadal men 200 mg intramuscular TC caused a threefold rise in serum T (peak values, days 2 to 5), a 33% increase in % free T (%FT) (days 2 to 7), and a 4.5-fold rise of absolute FT (peak on days 2 to 3), a 66% increase in % nonsex hormone-binding globulin-bound T (%non-SHBG-T) (peak days 2 to 7), a sixfold increase in absolute non-SHBG-T (peak days 4 to 5), and a threefold rise of estradiol (days 2 to 7). Many of the men achieved androgen concentrations (T, FT, and non-SHBG-T) above the respective normal concentrations between days 2 and 7; then steroid values declined to basal levels by days 13 to 14. Non-SHBG-T showed the largest-fold absolute increase and on day 4 to day 5 averaged three times the mean in normal men. Five men achieved non-SHBG-T values several times the upper limit of our total normal range. Luteinizing hormone became suppressed in men receiving their first intramuscular TC injection and remained suppressed in men receiving chronic TC. Thus, in hypogonadal men, biweekly injections of 200 mg TC result in wide variations in circulating androgen levels, from high to elevated shortly after intramuscular TC declining to basal by days 13 to 14.
Renal Pathology in von Hippel-Lindau Disease

Von Hippel-Lindau disease, a rare autosomal disorder, is associated with multiple lesions, including a high incidence of renal lesions and CNS hemangioblastomas. Renal lesions have traditionally been classified as either benign cysts or solid renal cell carcinomas with or without cystic degeneration. We examined seven kidney specimens from four patients with von Hippel-Lindau disease. We found that renal cysts form a histopathologic continuum ranging from benign cysts (with one to two cell layers of bland epithelium), atypical cysts (demonstrating epithelial hyperplasia with or without mild cytologic atypia), to malignant cysts harboring renal cell carcinoma. The presence of atypia or foci of carcinoma does not correlate with cyst size. Lesions that appear radiologically or grossly solid range from conventional solid renal cell carcinoma, sometimes evidencing cystic degeneration, to lesions that are predominantly hyalinized, fibrotic nodules. In contrast to simple cysts occurring in the general population, which are virtually always benign, renal cysts in patients with von Hippel-Lindau disease may contain occult carcinoma. Radiologic evaluation, visual inspection at surgery, and even frozen section analysis of cyst lesions cannot be relied on to detect small foci of carcinoma. The spectrum of pathologic changes and the multicentricity of the renal lesions in von Hippel-Lindau disease complicate the radiologic evaluation and surgical management of these patients.
Nephrolithiasis Following In Utero Diuretic Exposure: An Unusual Case

Reports have appeared in the literature describing the relationship between diuretic therapy and nephrocalcinosis or nephrolithiasis in groups of preterm infants. Most of the affected infants were receiving furosemide for the treatment of bronchopulmonary dysplasia. Here, we report an unusual case of nephrolithiasis related to in utero diuretic exposure. CASE REPORT The patient was born prematurely at 33 weeks9 gestation. The baby9s mother was 33 years old, gravada 1, para 0, and had blood type O. She was a class FR diabetic (retinopathy, nephropathy, systemic hypertension), with a medication regimen that included captopril, 25 mg, twice daily; hydralazine, 25 mg, twice daily; and ethacrynic acid, 50 mg, twice daily.
Avidin-Biotin Technique is More Sensitive Than Lectin Assay for Detecting the Thomsen-Friedenreich Antigen (T-Antigen) in Transitional Cell Carcinoma of the Bladder

Avidin biotin technique and lectin assay has been compared in a double-blind study for detection of the T-antigen in transitional carcinoma of the bladder. Utilizing the tumor registry from the U.S. Naval Hospital in Bethesda, Maryland, patients with transitional cell carcinoma of the bladder were identified. Thirty-three patients were selected with a total of 43 specimens. Tissues from 26 patients with a total of 43 specimens that showed no lesions and had no known history of genitourinary diseases were used as controls. These tissues were studied for the presence of T-antigen utilizing avidin biotin or lectin techniques. T-antigen was detected in 60% of the specimens with lectin technique, while 95% was detected with avidin biotin methods. The T-antigen was not detected by either method even after the treatment with neuraminidase in six patients. These patients had high grade and high stage tumors. This study demonstrated that normal urothelium has concealed T-antigen that can be exposed by treating the tissue with neuraminidase. However, the T-antigen is unconcealed in low grade tumor but disappears in high grade invasive tumor. Avidin biotin technique appears to be a more sensitive method for detecting the presence or absence of the T-antigen.
Henoch-Schönlein Purpura and the Acute Scrotum

Scrotal involvement occurs in between 2% and 38% of patients with Henoch-Schonlein purpura. We report on a child in whom acute scrotal swelling was the initial presentation of this syndrome. In only four previous cases have the initial symptoms of Henoch-Schonlein purpura been suggestive of testicular torsion.
Restoration of Renal Function After Bilateral Renal Artery Occlusion

• Five patients had anuric renal failure caused by occlusion of the main renal arteries. All had a background of controlled hypertension, but in three patients, hypertension accelerated in the months before anuria. Extensive atherosclerotic disease was clinically evident in the peripheral (3/5), coronary (4/5), and cerebral (1/5) vessels. Identifiable precipitating events preceded the development of anuria in four patients. Although the use of renal ultrasonogram and scintiscan was suggestive, angiography was essential to establish the diagnosis after a brief period of maintenance hemodialysis. Renal artery revascularization performed as long as 38 days after the onset of anuria resulted in restoration of kidney function. ( Arch Intern Med 1981;141:1647-1651)
The solution of Hydrogen in TaV2

Abstract TaV 2 may be prepared as a random b.c.c. alloy or as a (C-15) Laves phase. The behavior of hydrogen dissolved in b.c.c. TaV 2 is significantly different than that exhibited by hydrogen dissolved in (C-15) TaV 2 . The b.c.c. TaV 2 /H 2 ; system is similar to pure vanadium/H 2 ; in the region of hydrogen solid solution, the electronic contribution to the thermodynamics of solution is negligible and the system exhibits apparent H-H attractive interactions. A non-stoichiometric f.c.c. dihydride is formed at p H 2 = 10 atm, T = 273 K. ( C -15) TaV 2 does not form a hydride phase; hydrogen is continuously absorbed into solid solution to a maximum hydrogen content H / M ≅ 0.60. The solid solution of hydrogen in (C-15) TaV 2 exhibits trends which are typical of intermetallie/H 2 systems. The dilute hydrogen region is marked by a strong positive deviation from Sieverts' Law, and the relative partial molar enthalpy of solution becomes less exothermic as the hydrogen content is increased. ΔV vs H / M relationships and Δ S H vs H / M relationships indicate that hydrogen segregation at the metal surface or at abnormally stable trapping sites does not contribute significantly to the thermodynamic behavior exhibited by hydrogen in (C-15) TaV 2 . Analysis of the excess free energy of hydrogen suggests that electronic effects may exert a significant influence on the behavior of hydrogen in (C-15) TaV 2 , even at dilute hydrogen contents. It is suggested that the radom substitution of tantalum into the vanadium lattice exerts a significantly greater effect on the vibrational entropy of dissolved hydrogen than does the structural transformation b.c.c. TaV 2 → (C-15) TaV 2 .
Hidden Randomness between Fitness Landscapes Limits Reverse Evolution

In biological evolution, adaptations to one environment can in some cases reverse adaptations to another environment. To study this "reverse evolution" on a genotypic level, we measured the fitness of E. coli strains with each possible combination of five mutations in an antibiotic-resistance gene in two distinct antibiotic environments. While adaptations to one environment generally lower fitness in the other, we find that reverse evolution is rarely possible and falls as the complexity of adaptations increases, suggesting a probabilistic, molecular form of Dollo's law.
Plant Water Balance – its Relationship to Atmospheric and Edaphic Conditions

ABSTRACT Kaufmann, M. R. and Hall, A. E., 1974. Plant water balance – its relationship to atmospheric and edaphic conditions. Agric. Meteorol., 14: 85–98. An adaptation of Van den Honert's model of the soil–plant–atmosphere continuum is useful for understanding how leaf water potential is influenced by soil and atmospheric factors in the complex natural environment. In field-grown citrus, climatic and leaf resistance changes causing increased transpiration rates resulted in reduced leaf water potentials; however, the relationship between leaf water potential and transpiration was influenced by soil water potential and soil temperature, as predicted by the model adaptation. Leaf water potentials of young greenhouse-grown sunflower and sesame plants remained constant and high over a broad range of transpiration rates, suggesting a much more efficient water transport system for these plants. The comparison of the relationship between plant water balance and transpirational flux for contrasting species and environments is a promising approach for understanding the suitability of crop plants for their environment.