cssi/SciSciGPT-SciSciNet huggingface dataset:
Joint blind signal detection and carrier recovery over fading channels

A scheme of joint blind signal detection and carrier recovery is developed for intersymbol interference channels. Using a blind sequence estimation scheme, the proposed approach does not require explicit channel identification. It shows robustness against timing error and carrier phase uncertainty. The efficacy of the proposed approach is demonstrated in a simulation involving frequency selective fast fading channel with substantial Doppler shifts.
The Amino- and Carboxyl-terminal Residues and the Self-digestion of Bovine Pancreatic Carboxypeptidase A

Abstract : The generic term carboxypeptidase A applies to an enzyme which can be prepared by three different procedures yielding preparations which differ from each other chemically in amino acid composition, in NH2-terminal residues, and in solubility. In the present study, the terminal amino acid residues of each of the preparations were identified. In addition, quantitative data are presented to demonstrate a hitherto undetected heterogeneity in the COOH-terminal region of these enzymes. This heterogeneity involves a single amino acid replacement which probably is an expression of a genetic trait. (Author)
Non-organic failure to thrive: decision for placement and videotaped evaluations

Infants hospitalized for non-organic failure to thrive in the first six months of life are in a life-threatening situation and are already at risk for poor bonding with mother. In light of this, the meaning and use of foster care and how this separation affects the developing mother-child relationship are the issues addressed through examination of 16 cases in which 8 of the infants were placed in foster care and 8 discharged home after the failure to thrive hospitalization. This paper examines (1) maternal histories of pregnancy, labor and delivery and the neonatal status of placed and non-placed infants; (2) the developmental and weight status of placed children; (3) the nature of the decision criteria for after-hospital care; and (4) the mother-infant relationship at initial intake in terms of mother's report of events and observations of feeding and play interactions during a videotaped assessment process. The study found that the interactions between mother and infant in those situations which required foster care were clearly more dysfunctional when compared to those in which the baby was discharged home to mother. Babies in the two groups were comparable in weight status at the time of hospitalization although babies in foster placement had slightly lower scores on the Bayley Scales. Maternal histories of pregnancy, labor, and delivery were similar for the two groups as were the birth and neonatal histories of the infants.
Comparison of Disulfide Contents and Solubility at Alkaline pH of Insecticidal and Noninsecticidal Bacillus thuringiensis Protein Crystals.

Abstract We compared two insecticidal and eight noninsecticidal soil isolates of Bacillus thuringiensis with regard to the solubility of their proteinaceous crystals at alkaline pH values. The protein disulfide contents of the insecticidal and noninsecticidal crystals were equivalent. However, six of the noninsecticidal crystals were soluble only at pH values of ≥12. This lack of solubility contributed to their lack of toxicity. One crystal type which was soluble only at pH ≥12 (strain SHP 1-12) did exhibit significant toxicity to tobacco hornworm larvae when the crystals were presolubilized. In contrast, freshly prepared crystals from the highly insecticidal strain HD-1 were solubilized at pH 9.5 to 10.5, but when these crystals were denatured, by either 8 M urea or autoclave temperatures, they became nontoxic and were soluble only at pH values of ≥12. These changes in toxicity and solubility occurred even though the denatured HD-1 crystals were morphologically indistinguishable from native crystals. Our data are consistent with the view that insecticidal crystals contain distorted, destabilized disulfide bonds which allow them to be solubilized at pH values (9.5 to 10.5) characteristic of lepidopteran and dipteran larval midguts.
Evaluation of a commercial flatbed document scanner and radiographic film scanner for radiochromic EBT film dosimetry

The purpose of this study was to quantify the performance and assess the utility of two different types of scanners for radiochromic EBT film dosimetry: a commercial flatbed document scanner and a widely used radiographic film scanner. We evaluated the Epson Perfection V700 Photo flatbed scanner and the Vidar VXR Dosimetry Pro Advantage scanner as measurement devices for radiochromic EBT film. Measurements were made of scan orientation effects, response uniformity, and scanner noise. Scanners were tested using films irradiated with eight separate 3×3cm2 fields to doses ranging from 0.115–5.119 Gy. ImageJ and RIT software was used for analyzing the Epson and Vidar scans, respectively. For repeated scans of a single film, the measurements in each dose region were reproducible to within ± 0.3% standard deviation (SD) with both scanners. Film-to-film variations for corresponding doses were measured to be within ± 0.4% SD for both Epson scanner and Vidar scanners. Overall, the Epson scanner showed a 10% smaller range of pixel value compared to the Vidar scanner. Scanner noise was small: ± 0.3% SD for the Epson and ± 0.2% for the Vidar. Overall measurement uniformity for blank film in both systems was better than ± 2%, provided that the leading and trailing 2 cm film edges were neglected in the Vidar system. In this region artifacts are attributed to the film rollers. Neither system demonstrated a clear measurement advantage. The Epson scanner is a relatively inexpensive method for analyzing radiochromic film, but there is a lack of commercially available software. For a clinic already using a Vidar scanner, applying it to radiochromic film is attractive because commercial software is available. However, care must be taken to avoid using the leading and trailing film edges.
Polymorphism in fowl serum albumin: III. KCl concentration effects on the yield and activity of chicken liver ribosomes

Abstract The effect of ionic strength during isolation on the activity of chicken liver ribosomes in a poly(U)-dependent phenylalanine-incorporating system was studied. Changing KCl concentration during isolation caused ribosome yield and activity to vary significantly. KCl concentrations of 150–250 mM in the isolation medium resulted in higher and more consistent ribosome yields and activity than 25–50 mM, although KCl concentration was the same in all assay mixtures (150 mM). Thus, the reduced activity characteristic of chicken ribosomes isolated at low KCl concentrations is not readily reversible in the assay mixture. The reduced yield and activity may result from a greater tendency of ribosomes isolated at low KCl concentrations to aggregate. The effects of cell-sap concentration, MgCl 2 concentration, and temperature during incubation were also determined, as well as the results of freezing ribosomes and cell sap before use. The optimum MgCl 2 concentration for phenylalanine incorporation was about 14 mM, and the optimum temperature for a 60-min incubation was 33–37 °C.
Methodological standards and strategies for establishing the evidence base of animal-assisted therapies

Publisher Summary The goal of this chapter is to foster scientific evaluation of animal-assisted therapy (AATs) in contexts to improve the social, emotional, behavioral adjustment or adaptive functioning or to ameliorate some psychological or psychiatric condition among children and adolescents. The current status of psychotherapy (non-animal assisted) for children is presented as a backdrop to convey current methodological standards for intervention research. The discussion moves from conceptual underpinnings of an investigation, to the specific question that is asked about treatment, and to control and comparison conditions pivotal to AAT research. Key concepts that are addressed or emerge in therapy include the patient/therapist relationship and bond, support, attachment, and friendship. Common methodological practices in AAT research that interfere with drawing conclusions about the effects of treatment are highlighted. The benefits of therapy are considered to include developing awareness, empathy, and increased interpersonal sensitivity, making individuals feel better, reducing stress, and improving the quality of life. The chapter concludes by proposing next steps for research; these are intended to advance both the conceptual understanding of AATs and the conclusions about their impact on child functioning.
The Distribution of Mutant Alleles in a Subdivided Population

ABSTRACT The results are presented from a simulation study of the spatial distribution of mutant alleles in a subdivided population. Statistical measures of the spatial pattern are defined in such a way that the same quantities could be measured in a geographic survey of allele frequencies in natural populations. Two types of quantities are discussed in this paper: (1)the occupancy distribution provides information on the presence or absence of the mutant in different numbers of demes; and (2) the conditional frequency distribution provides information about the extent of local differentiation when the mutant is present in different numbers of demes. Properties of these distributions are found for different types of natural selection acting on the mutant. Some results are presented for the same statistical measures based on samples of individuals from a fraction of the total number of demes. The simulation results for intermediate levels of the migration rates are compared with analytic results obtained on the limits of high and low migration rates. The main conclusion is that these measures of the spatial distribution of mutants in a subdivided population have simple properties that could provide a new perspective on data from natural populations.
Does the tympanic membrane have a natural opening? The historical saga of the foramen of Rivinus.

Objectives From the end of the 17th century until well into the 20th century, the question of whether the tympanic membrane possesses a natural opening or not in its normal state has been the subject of much controversy. The aim of this study was to go back to the original documents describing this tympanic foramen, and to follow through the centuries the various controversies and discussions surrounding the presence or not of this foramen. Data Sources Selected otological textbooks and articles from the end of the 17th century until the second part of the 20th century. Review Method Historical. Results This study demonstrates the tenacity of the human brain in its regular review of questions that seem to have been answered, even when universal acceptation of said answer is almost present. The controversy around the foramen of Rivinus spanned nearly 300 years, until the mid-20th century. Conclusions The introduction of the regular use of an ear microscope to practice otoscopy gave the definitive answer: the tympanic membrane does not have a natural opening in its normal state. Level of Evidence NA Laryngoscope, 125:448–452, 2015
Determination of X-Ray Photoemission Line-Shape Asymmetries from Threshold Exponents

The law of conservation of charge is used to express the x-ray photoemission spectroscopy (XPS) line shape of a metal in terms of its observed threshold exponents, ${\ensuremath{\alpha}}_{0}$ and ${\ensuremath{\alpha}}_{1}$, within the framework of the many-electron theories of Doniach, Sunjic, Mahan, Nozi\`eres, and de Dominicis. The many-body theory predicts an anomalous dependence of XPS asymmetry on conduction-electron density: With increasing density, the XPS line should become more symmetric.
In Search of Rational Government: What Political Preference Function Studies Measure and Assume

Political preference function (PPF) studies assume that policy-making can be described by a mathematical problem in which a rational government maximizes a function of interest groups' welfares. The purpose of my paper is to explain in-depth ramifications of PPF study assumptions and methodology. PPF studies that attempt to measure interest group political power do so by measuring marginal rates of transformation along a Pareto frontier. One can estimate political power with a PPF only if observed policies are Pareto-efficient, which may depend on the assumed number of interest groups and policy instruments. Marginal rates of transformation need not reveal anything meaningful about interest group political power, and may incorrectly measure the direction of transfers.
On the approximation of the thermal conductivity of rigid heat conductors as a Cauchy Problem

It is shown that the material response function of a nonlinear rigid heat conductor may be viewed as the solution to a Cauchy Problem. The measurements necessary to determine sufficient initial and characteristic data are indicated.
Desarrollo urbano y decadencia económica en la España moderna

En anos recientes se han realizado nuevas interpretaciones sobre la decadencia de Espana y la relacion entre el declinar politico de los Austrias y la decadencia economica de Castilla. Este trabajo vuelve a examinar dicha relacion empleando conceptos tomados de la geografia economica y el desarrollo urbano. Con ello proporciona un marco teorico en el que se incluyen tres cuestiones historicas: la decadencia de Espan;a, la efectividad de los Austrias en la consolidacion del Estado y el persistente estancamiento del interior de Espan;a.
A Hamada type characterization of the classical geometric designs

The dimension of a combinatorial design $${{\mathcal D}}$$ over a finite field F = GF(q) was defined in (Tonchev, Des Codes Cryptogr 17:121---128, 1999) as the minimum dimension of a linear code over F that contains the blocks of $${{\mathcal D}}$$ as supports of nonzero codewords. There it was proved that, for any prime power q and any integer n � 2, the dimension over F of a design $${{\mathcal D}}$$ that has the same parameters as the complement of a classical point-hyperplane design PG n-1(n, q) or AG n-1(n, q) is greater than or equal to n + 1, with equality if and only if $${{\mathcal D}}$$ is isomorphic to the complement of the classical design. It is the aim of the present paper to generalize this Hamada type characterization of the classical point-hyperplane designs in terms of associated codes over F = GF(q) to a characterization of all classical geometric designs PG d (n, q), where 1 � d � n � 1, in terms of associated codes defined over some extension field E = GF(q t ) of F. In the affine case, we conjecture an analogous result and reduce this to a purely geometric conjecture concerning the embedding of simple designs with the parameters of AG d (n, q) into PG(n, q). We settle this problem in the affirmative and thus obtain a Hamada type characterization of AG d (n, q) for d = 1 and for d > (n � 2)/2.
Interferon-γ and Ia antigen are present on astrocytes in active chronic multiple sclerosis lesions

Using immunocytochemical techniques, presence of interferon (IFN)-gamma, IFN-alpha and Class II major histocompatibility (MHC) antigen (HLA-DR, Ia) was evaluated in active central nervous system (CNS) lesions of 11 patients with chronic multiple sclerosis (MS) and the findings were correlated with a detailed analysis of inflammatory cells. Both IFN-gamma and Ia antigen were detectable on astrocytes at the edge of active chronic MS lesions and in the adjacent normal-appearing white matter, where CD4+ (helper/inducer) T cells and interleukin-2 receptor (IL-2R)-positive cells were also found. IFN-alpha was predominantly seen on Ia-positive macrophages and not on astrocytes. Astroglia in the inactive lesion center and in normal CNS parenchyma were unreactive for both types of IFN and Ia antigen. These findings suggested that similar to the situation in vitro, IFN-gamma can also induce Ia-expression on astrocytes in vivo. Via local antigen presentation, IFN-gamma might thus play an important role in the development of MS lesions, while IFN-alpha might be involved in local immunosuppression.
Modeling primordial gas in numerical cosmology

Abstract We have reviewed the chemistry and cooling behavior of low-density (n ≲ 10 4 cm −3 ) primordial gas and devised a model which involves 19 collisional and 9 radiative processes and is applicable for temperatures in the range 1 K T 8 K. In a companion paper (Anninos et al., 1997)[NewA, 2, 209] numerical methods are presented that unify the modeling of non-equilibrium primordial gas chemistry and cooling dicussed here with cosmological hydrodynamics. We derived new fits of rate coefficients for the photo-attachment of neutral hydrogen, the formation of molecular hydrogen via H − , charge exchange beween H 2 and H + , electron detachment of H − by neutral hydrogen, dissociative recombination of H 2 + with slow electrons, photodissociation of H 2 + , and photodissociation of H 2 . Furthermore it was found that the molecular hydrogen produced through the gas-phase processes, H 2 + + H → H 2 + H + , and H − + H → H 2 + e − , is likely to be converted into its para configuration on a faster time scale than the formation time. We have tested the model extensively and shown it to agree well with former studies. We further studied the chemical kinetics in great detail and devised a minimal model which is substantially simpler than the full reaction network but predicts correct abundances. This minimal model shows convincingly that 12 collisional processes are sufficient to model the H, He, H + , H − , He + , He ++ , and H 2 abundances in low density primordial gas for applications with no radiation fields.
Accumulation of sulfate by mitochondria of rat kidney cortex.

Twice washed mitochondria from rat kidney cortex can accumulate sulfate ions from low (10-7 M) ambient concentrations to create virtual gradients of several hundred to one. This sulfate is subsequently released. The activation energy for the uptake is 12,000 calories per mole; for release it is about 30,000 calories per mole. Variations in the sulfate concentration of the medium show that there is a straight line Freundlich adsorption isotherm over a million-fold range of concentration of sulfate in the medium. There are 9 x 104 sites at 10-5 M and 9 x 105 sites at 10-3 M sulfate per average single mitochondrion. Preincubation at 30°C rapidly destroys the ability to accumulate sulfate. Partial protection occurs if oxidative phosphorylation is proceeding during the preincubation. The concentration of the endogenous inorganic sulfate of twice washed mitochondria is 4.2 x 10-4 moles per liter of mitochondrial pellet water; 99.85 per cent of this endogenous sulfate is inexchangeable with external sulfate in vitro. It is all exchangeable in vivo. The pH optimum for accumulation of radiosulfate from dilute external sulfate concentrations is 5.5. These observations show that there is a delicate and specific mechanism in mitochondria from kidney cortex which accumulates sulfate. The chemical nature of the accumulated sulfate is unknown.
Functional decline in lower-extremity peripheral arterial disease: associations with comorbidity, gender, and race.

Purpose To identify comorbidities associated with increased rates of functional decline in persons with lower-extremity peripheral arterial disease (PAD). We also determined whether female sex and black race were associated with greater functional decline than male sex and white race, respectively, in PAD. Methods Three-hundred ninety-seven men and women with PAD were followed prospectively for a median of 36 months. The presence of comorbid illnesses was determined with medical record review, patient report, medications, laboratory values, and a primary care physician questionnaire. Functional outcomes, measured annually, included the 6-minute walk, usual-paced and fast-paced 4-meter walking speed, and summary performance score. The summary performance score is a composite measure of lower-extremity functioning (score range, 0 to 12; 12=best). Results Adjusting for known and potential confounders, PAD patients with pulmonary disease had a significantly greater average annual decline in 6-minute walk performance of −34.02 ft/y (95% confidence interval [CI], −60.42 to −7.63; P = .012), rapid-paced 4-meter walk speed of −0.028 m/s/y (95% CI, −0.054 to −0.001; P = .042), and summary performance score of −0.460/y (95% CI, −0.762 to −0.157; P = .003) compared with those without pulmonary disease. PAD patients with spinal stenosis had a greater average annual decline in 6-minute walk performance of −77.4 ft/y (95% CI, −18.9 to −35.8; P P = .014) compared with participants without spinal stenosis. Conclusion At 3-year follow-up, pulmonary disease and spinal stenosis were each associated with a significant decline in functioning among persons with PAD. In contrast, female sex and black race were not associated with functional decline among persons with PAD.
Tissue engineering of flexor tendons.

Flexor tendon repair continues to challenge hand surgeons despite advances in suture repair techniques and rehabilitation protocols. Postoperative adhesions remain a possible sequelae of flexor tendon repair. There is a continued need for additional tendon graft material in severely traumatized hands. Tissue engineering methods through ex vivo manufacturing or in vivo regeneration of flexor tendons may help address these problems. Ex vivo manufacturing involving biodegradable scaffolds has recently led to successful generation of flexor tendons in animal models. Molecular advances in the biology of tendon healing and regeneration have highlighted the important role of several growth factors. Understanding of the biomolecular interaction of these cytokines will give surgeons the ability to direct flexor tendon healing and regeneration. The goal of flexor tendon tissue engineering will be to provide molecular methods and materials that can be used to restore normal form and function in the hand.
Structure and adsorption properties of commercial calcium phosphate adjuvant.

Abstract Calcium phosphate adjuvant is a commercially available vaccine adjuvant that potentiates the immune response to antigens. Although its name suggests that it is Ca 3 (PO 4 ) 2 , X-ray diffraction, FTIR spectroscopy, thermal analysis and the Ca/P molar ratio identify commercial calcium phosphate adjuvant as non-stoichiometric hydroxyapatite, Ca 10− x (HPO 4 ) x (PO 4 ) 6− x (OH) 2− x , where x varies from 0 to 2. The surface charge is pH-dependent (point of zero charge = 5.5). Consequently, commercial calcium phosphate adjuvant exhibits a negative surface charge at physiological pH and electrostatically adsorbs positively charged antigens. The presence of hydroxyls allows calcium phosphate adjuvant to adsorb phosphorylated antigens by ligand exchange with surface hydroxyls.
Neglected Diseases Amid Wealth In The United States And Europe

Neglected tropical diseases are not exclusive to low-income countries. In the United States, such infections account for a sizable but largely hidden disease burden among minority populations living in poverty and among people of African descent in particular. Similar infections also occur in Europe. As efforts to control neglected tropical diseases expand throughout Africa, parallel efforts should also target poor and forgotten people in wealthy nations.
Government publications: A comparative use study

Abstract This article describes a study at the University of California, Irvine on the utilization of documents from all levels of government—federal, state, local, and international. Among the factors analyzed are: circulation versus in-house use, status of borrower, gender, classes of documents used, microfiche use, and date of publications used. In addition to broadening the scope of prior circulation and in-house use studies, a special effort was made to provide comparability with previous studies.
TU-B-230A-01: Informatics Systems Overview

Due to the increasing complexity of radiation therapy, government regulations, and legal liability, computerized radiationoncology information systems are becoming a necessity. Selection of an information system involves understanding of both computer software and hardware issues. Topics such as network infrastructure, software interfaces, and hardware interfaces, which are not part of the normal physics training, must be understood by the medical physicist. As the person with the most technical training in the radiationoncology department they will be called upon to do one or more of the following; specify a system, setup and installation, troubleshoot the system when things go wrong. This course will identify both hardware and software issues to consider when either first implementing a computerized information system or changing to an electronic treatment record. An overview/summary of the commercially available Record & Verify systems will also be presented. Educational Objectives: 1. Understand basic network infrastructure for both local area networks (LAN) and wide area networks (WAN). 2. Understand interfaces to both hospital information systems and various radiationoncology devices. 3. Understand differences in network requirements for both single department and multi‐department institutions. 4. Understand what is required when migrating from a paper treatment record to an electronic treatment record. 5. Be able to generate specifications for a radiationoncology information system. 6. Understand the personnel requirements for implementing and maintaining a radiationoncology information system. Conflict of Interest Statement Michael Herman — Research sponsored by Varian Medical Systems Corporation.
New laser methods for measuring complete defect dynamics—I. application to rare earth doped fluorites

Abstract Site selective laser methods are uniquely suited for studying systems where multiple defect centers are present. The development of kinetic methods has provided dramatic new insights into the defect structures present in fluorites.
Characterization of the PDFs of coordinate transformations in tracking

Target tracking in radar and sonar is often done in either spherical or rectangular coordinates. The objective of the work presented here is to provide a means to analytically characterize the probability density function (pdf) of these transformations. Such pdf can be used to accurately characterize the measurement statistics needed for filter design, simulation, and potentially, implementation. The results of this work provide the infrastructure to accomplish such goals for tracking filters.
cPKC-dependent Sequestration of Membrane-recycling Components in a Subset of Recycling Endosomes

Abstract In addition to the classical role of protein kinase C (PKC) as a mediator of transmembrane signals initiated at the plasma membrane, there is also significant evidence to suggest that a more sustained PKC activity is necessary for a variety of long term cellular responses. To date, the subcellular localization of PKC during sustained activation has not been extensively studied. We report here that long term activation of PKC (1 h) leads to the selective translocation of classical PKC isoenzymes, α and βII, to a juxtanuclear compartment. Jux-tanuclear translocation of PKC required an intact C1 and C2 domain, and occurred in a microtubule-dependent manner. This juxtanuclear compartment was localized close to the Golgi complex but displayed no overlap with Golgi markers, and was resistant to dispersal with Golgi disrupting agents, brefeldin A and nocodazole. Further characterization revealed that PKCα and βII translocated to a compartment that colocalized with the small GTPase, rab11, which is a marker for the subset of recycling endosomes concentrated around the microtubule-organizing center/centrosome. Analysis of the functional consequence of cPKC translocation on membrane recycling demonstrated a cPKC-dependent sequestration of transferrin, a marker of membrane recycling, in the cPKC compartment. These results identify a novel site for cPKC translocation and define a novel function for the sustained activation of PKCα and βII in regulation of recycling components.
An algorithm for routing with capacitance/distance constraints for clock distribution in microprocessors

In modern microprocessors, clocks are usually distributed employing a hybrid network, grid followed by buffered trees, to restrict the skew. This is typically done employing (gated) buffered trees inside the blocks, while the global grid overlay the entire die area. The block-level buffered trees are connected to the grid at specific locations, by routing the wires along the predetermined tracks. The routing of these clock wires, which consume noticeable power, have distance and capacitance constraints to avoid poor slopes at the inputs of the block-level buffers. Moreover, these wires also contribute to significant load on the clock grid. This leads to a problem of capacitance or wirelength minimization during the multi-terminal routing such that wires use pre-specified tracks and routes obey distance and capacitance constraints, i.e., the length of the route from any receiver to a connection on the grid-wire has less than the specified distance and the overall capacitance due to all receivers on the route is less than the given limit. Since the problem is intractable, we present an efficient algorithm that completes the routing connecting 1000s of terminals over a few $mm^2$ area in seconds, improving the wirelength by 17% over the commonly used nearest source heuristic. The algorithm is employed to perform post-grid clock distribution in a 45 nm technology microprocessor.
Guides to clinical aspiration biopsy: Pediatrics authors: Philippe Vielh and Lydia Pleotis Howell, Igaku‐Shoin, New York, 1993

Fine-needle aspiration biopsy (NAB) continues to be controversial in pediatric medicine, and is probably under-utilized in many practices. Although there have been several publications dealing with pediatric neoplasms and tumor-like conditions, there are few books which deal extensively with pediatric cytology. The purpose of this book is to provide both cytologists and clinicians with a systematic guide to cytodiagnosis by NAB in children. It seeks to dispel misconceptions, provide information on the utility of NAB, and summarize the current literature.
Starplasty: a new technique of pediatric tracheotomy

Objective To report a new technique of pediatric tracheotomy that reduces the problems of pneumothorax and recannulation after accidental decannulation in a recently performed tracheotomy. Design Retrospective chart review for 1990-1997. Patients Sixty-eight children aged between 2 days and 14 years. Method The starplasty procedure is based on the geometry of a 3-dimensional Z-plasty. The technique of the procedure is described and illustrated in detail. Results There were 27 short-term complications, including 4 accidental decannulations. There were no instances of pneumothorax or tracheotomy-related deaths. There were 25 long-term minor complications. There were no instances of tracheotomy-related death, suprastomal collapse, or tracheal stenosis. Thirty-eight children remain tracheotomy tube dependent, 17 underwent decannulation, 7 died of primary disease, and 6 were lost to follow-up. All 17 children who underwent decannulation have a persistent tracheocutaneous fistula. Conclusions I conclude that starplasty reduces the incidence of major complications and death. Its only drawback seems to be persistent tracheocutaneous fistula.
Property rights as a complex adaptive system: how entrepreneurship transforms intellectual property structures

This article aims to provide some elements of an evolutionary theory of property rights. It applies a systems-based capital-theoretic perspective to explain the formation and transformation of property rights structures. The approach emphasizes how entrepreneurs create capital combinations by connecting capital goods—defined widely to include property rights, such as patents—in their production plans. Their actions change complementarity relations between property rights as used in production. We treat the property rights structure as a complex adaptive system that exhibits increasing structural complexity as it evolves. Entrepreneurs discover gaps in the property rights system. As they organize production to exploit profit opportunities, entrepreneurs regroup existing intellectual property rights (IPR) into new modules, such as patent pools, that encapsulate more complex combinations of basic building blocks of intellectual property. A patent pool constitutes an interpolation of a new meso level within the macro IPR structure. We apply our framework to the first of the patent pools for digital video compression technology used in digital television and DVDs.
Comparison of subject-specific and population averaged models for count data from cluster-unit intervention trials

Maximum likelihood estimation techniques for subject-specific (SS) generalized linear mixed models and generalized estimating equations for marginal or population-averaged (PA) models are often used for the analysis of cluster-unit intervention trials. Although both classes of procedures account for the presence of within-cluster correlations, the interpretations of fixed effects including intervention effect parameters differ in SS and PA models. Furthermore, closed-form mathematical expressions relating SS and PA parameters from the two respective approaches are generally lacking. This paper investigates the special case of correlated Poisson responses where, for a log-linear model with normal random effects, exact relationships are available. Equivalent PA model representations of two SS models commonly used in the analysis of nested cross-sectional cluster trials with count data are derived. The mathematical results are illustrated with count data from a large non-randomized cluster trial to reduce underage drinking. Knowledge of relationships among parameters in the respective mean and covariance models is essential to understanding empirical comparisons of the two approaches.
A simple technique for interventional tool placement combining fluoroscopy with interventional computed tomography on a C-arm system.

BACKGROUND: Flat-panel cone-beam computed tomography (FP-CBCT) has recently been introduced as a clinical feature in neuroangiography radiographic C-arm systems. OBJECTIVE: To introduce a method of positioning a surgical tool such as a needle or ablation probe within a target specified by intraoperative FP-CBCT scanning. METHODS: Two human cadaver and 2 porcine cadaver heads were injected with a mixture of silicone and contrast agent to simulate a contrast-enhanced tumor. Preoperative imaging was performed using a standard 1.5-T magnetic resonance imaging scanner. Intraoperative imaging was used to define the needle trajectory on a GE Innova 4100 flat panel-based neuroangiography C-arm system. RESULTS: Using a combination of FP-CBCT and fluoroscopy, a needle was successfully positioned within each of the simulated contrast-enhanced tumors, as verified by subsequent FP-CBCT scans. CONCLUSIONS: This proof-of-concept study demonstrates the potential utility of combining FP-CBCT scanning with fluoroscopy to position surgical tools when stereotactic devices and image-guided surgery systems are not available. However, further work is required to fully characterize the precision and accuracy of the method in a variety of realistic surgical sites.
Influenza vaccines and guillain-barre syndrome: the continuing question.

Influenza is a global public health problem, with complications of seasonal influenza resulting in thousands of deaths and substantial morbidity worldwide. Periodically, particularly virulent viral strains emerge, resulting in more infections and fatalities (e.g., influenza A [H1N1] virus and influenza A/H5N1, “bird flu”). Influenza infection may be prevented or mitigated by vaccination; seasonal vaccine is highly effective in reducing clinical illness and limiting viral spread through respiratory droplets.
Experimental Study of Effects of Volumetric Porosity and Critical Meniscus Radius on Evaporation/Boiling From Thin Capillary Wicks

The evaporation/boiling heat transfer and critical heat flux (CHF) from surfaces coated with multiple, uniform layers of sintered isotropic copper mesh were studied experimentally in an atmospheric environment. Two series of investigations were conducted: one was designed to study the effects of the critical meniscus radius and effective pore size, which are controlled by the wire diameter and mesh number, with the volumetric porosity and wick thickness are held constant; and a second to study the effects of volumetric porosity for a constant wick thickness and effective pore size. The experimental results indicate that the critical heat flux (CHF) was strongly dependent on the critical meniscus radius and effective pore size, as well as the volumetric porosity; while the evaporation/boiling heat transfer coefficient was significantly affected by critical meniscus radius and effective pore size, but not strongly dependent on the volumetric porosity. The data further illustrate that the menisci at CHF are located in the corner formed by wire and heated wall and between the wires in both the vertical and horizontal directions. The minimum value of these three menisci determined the maximum capillary pressure generated through the capillary wick. Sample structure and fabrication processes as well as the test procedures, are described in detail and discussed. The experimental results and observations are systematically presented and analyzed.Copyright © 2005 by ASME
395 HEMODYNAMIC CONSEQUENCES OF NITROGLYCERIN INFUSION DURING GROUP B STREPTOCOCCAL SEPSIS IN PIGLETS

Cardiovascular collapse is a common cause of death in newborn sepsis. Vasodilator therapy has recently been suggested to be of significant hemodynamic benefit in a number of shock states. We assessed the effects of nitroglycerin (NG), a direct-acting smooth muscle relaxant, on systemic and pulmonary hemodynamics in a piglet model of Group 8 Streptococcal sepsis. Piglets (n=4) were anaesthetized, intubated, and ventilated. Systemic blood pressure (BP), pulmonary artery pressure (PAP), cardiac output (CO), and heart rate (HR) were monitored directly and continuously. Sepsis was induced by continuous infusion of serotype Ib Group B Streptococci (GBS) @ approximately 5 × 107 organisms/kg/min. Ventricular filling pressures were held constant during the entire experiment by adjustment of i.v. infusion rate. After 30 minutes of GBS infusion, CO fell by 32 ± 7% (S.D.), PAP rose by 225 ± 97% (both p< 0.01) while BP fell by 1 ± 6% and HR rose b 4 ± 4% (both p = N.S.) While GBS infusion continued, NG infusion was begun. For NG @ 8 mcg/kg/min and 16 mcg/kg/min respectively, CO fell by 7 ± 9% (p = N.S.) and 19 ± 11% (p< 0.01), BP fell by 9 ± 6% (p< 0.05) and 13 ± 4% (p< 0.01), PAP rose by 2 ± 9% and 4 ± 16% (both p = N.S.), and HR rose by 7 ± 9% (p = N.S.) and 11 ± 6% (p< 0.05). Conclusion: NG infusion during GBS sepsis in piglets had little apparent hemodynamic benefit.
Primary thyroid lymphoma: can the diagnosis be made solely by fine-needle aspiration?

Background Primary malignant lymphoma fo the thyroid accounts for <5% of all thyroid malignancies and is primarily treated with chemotherapy and external beam radiation. With the advent of modern immunophenotypic analyses, fine-needle aspiration (FNA) can potentially obviate the need for surgical procedures.
Visualizing multiple fields on the same surface

A long-standing problem in the field of visualization is the ability to display many overlaid data sets. Researchers have developed successful techniques that show multiple 3D fields by layering sparse similar glyphs. My colleagues and I at the University of North Carolina have investigated this problem for a number of years. Our driving application has been the display of data sets from scanned-probe and scanned-electron microscopes, which led us to concentrate on the display of multiple scalar fields. Although several of our first approaches were initially successful, they failed to scale to more than three or four data sets. So that others will not be tempted to follow the same course, I begin by presenting the argument for, preliminary successes with, and reasons for the eventual downfall of our initial approach. I then describe the key concept that enables successful techniques.
Investment Returns of Life Insurers: Tests of Agency Theory and its Alternatives

Agency theory leads to proposals that managers of asset portfolios would not necessarily maximize net return on invested assets for any level of risk. Because investment income accounts for approximately one third of the total income of life insurers, the rate of return on invested assets can substantially affect an insurer's products and profitability. Prior research has shown systematic differences in general insurance expenses between classes of insurers, but continued viability of all classes of insurers through time. This study tests the predictions of agency theory and its alternatives concerning the investment yields of life insurers and finds offsetting differences in the investment results of these insurers. The study also finds significant economies of scale in the investment function that help explain what might otherwise appear to be an unjustified emphasis on firm growth. This study has important implications for participants in the industry, regulators, consumers and investors.
A cell-surface molecule involved in organ-specific homing of lymphocytes

Lymphocytes migrate from the bloodstream by recognizing and binding to specialized endothelial cells lining the high endothelial venules (HEV) in lymph nodes and Peyer's patches. We describe here a monoclonal antibody, MEL-14, specific for a lymphocyte surface molecule that appears to mediate recognition of lymph node HEV, and to be required for lymphocyte homing into lymph nodes in vivo.
Dielectric coatings for Ag/dielectric hollow glass waveguides

Different dielectric thin films are being studied in order to facilitate the processing of low loss multiple metallic dielectric hollow glass waveguides (HGWs). In this paper, we present our results for high index lead sulfide (PbS) and low index optical polymers, especially, polystyrene (PS) and cyclic olefin polymer (COP). We have observed that the morphology of the thin film is dependent on the processing conditions. The morphology of the metal and dielectric thin film affects the attenuation of the hollow glass waveguides. We have been successful in depositing and controlling the morphology of high n PbS thin films and low n polymer films. In order to aid in thin film characterization we have also deposited on planar substrates.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Recent advances in our understanding of the metabolism of vitamin D and its regulation.

SUMMARY Potent new methods of separation of vitamin D metabolites and analogues have been developed using high pressure liquid chromatography and silica gel columns. Utility of this new method in the further study of vitamin D metabolism has been demonstrated. With this technique it has been possible to demonstrate that the natural product, 24,25-dihydroxyvitamin D3 (24,25-(OH)2D3), has its hydroxyl in the R configuration. With 3H-1α-hydroxyvitamin D3 (1α-OH-D3), which has been recently synthesized in this laboratory, it has been possible to show that it is rapidly converted to 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) predominantly by liver and that this conversion occurs in ample time to account for its biological activity. Chick intestine possesses some 25-hydroxylating ability whereas rat intestine does not. It seems likely that 1α-OH-D3 is biologically active almost entirely by virtue of its conversion to 1,25-(OH)2D3. The 24R,24,25-(OH)2D3 is almost as biologically active as 25-hydroxyvitamin D3 (25-OH-D3) in the rat, but has low activity in the chick. The S isomer is essentially without activity in either species except for intestinal calcium transport in the rat. Radioactive 24,25-(OH)2D3 has been used to demonstrate that in the chick it is rapidly metabolized and excreted suggesting that the 24-hydroxylation in the chick is an important biological inactivation mechanism. In the rat it is possible that the 24-hydroxylation has functional significance. Finally, the 1α-hydroxylase of 25-OH-D3 in chick kidney has been successfully solubilized and the cytochrome P-450 as well as the renal ferredoxin has been isolated and recombined with beef adrenal flavoprotein to produce a reconstructed 25-OH-D3-1α-hydroxylase system with very high specificity and high enzymatic activity. The results show conclusively that the 1-hydroxylase system requires NADPH to reduce a flavoprotein which in turn reduces a renal ferredoxin which in turn reduces the cytochrome P-450. The cytochrome P-450 carries out the hydroxylation using molecular oxygen and 25-OH-D3.
Low amplitude EEGs in demented AIDS patients

Abstract We have observed an unusual low amplitude, slow and featureless electroencephalogram (EEG) pattern in some human immunodeficiency virus (HIV) infected patients without focal lesions on computerized tomography (CT scan) of the head. Out of 17 cases, 13 with AIDS and 4 with HIV positive status, 6 had low amplitude EEGs with slowing, all in the AIDS group. Nine of the 13 AIDS patients were demented, and 4 of these demented patients had slow verbal responses and mutism, indicating advanced HIV-related dementia. All 4 had low amplitude, slow EEGs. The patients with low amplitude, slow EEGs also had atrophy on CT scan by visual assessment and by measurement of ventricular indices. Of 17 age-matched controls referred for non-specific complaints such as headache and dizziness or for psychiatric disorders, 3 had EEGs read as low amplitude with slowing; two had normal mental status and one was psychotic. Although this EEG pattern is not etiologically specificit, may correlate with advanced dementia and atrophy on CT scan in AIDS patients.