cssi/SciSciGPT-SciSciNet huggingface dataset:
Network Analysis of Software Repositories: Identifying Subject Matter Experts

A software developer joining a large software project faces a steep learning curve before they are able to make real contributions. One challenge is finding the subject matter experts who can answer questions about a specific area of the software or to review changes. This is especially true of large projects with many modules and a large number of authors. In this paper, we describe a method to model a software project as a network using information mined from the project’s version control repository, and demonstrate how network analysis techniques can be used to identify the key authors and subject matter experts. We investigate metrics that can be gathered using network analysis, such as which groups of authors typically work together, and how closely knit the developers are on a project. We analyze several specific projects to demonstrate the applicability of these techniques and several hundred projects to show general trends.
Combined association of physical activity and diet with C-reactive protein among smokers

In the general population, both physical activity and dietary behavior are independently associated with less systemic inflammation, with this relationship less examined among smokers. To our knowledge, no study has examined the combined association of both physical activity and dietary behavior on systemic inflammation among daily smokers, which was the purpose of this study. Data from the 2003–2006 NHANES were employed. 810 adult smokers provided C-reactive protein data (CRP; a marker of inflammation), and sufficient physical activity (accelerometry) and dietary data (healthy eating index). The fully adjusted model showed that participants meeting physical activity guidelines and eating a healthy diet (β = −0.34, p = 0.03) had lower CRP levels when compared to those not engaging in these health behaviors, but only having one health behavior was not a significant predictor of CRP (β = −0.19, p = 0.14). Smokers engaging in regular physical activity while consuming a healthy diet demonstrate lower CRP levels than their counterparts. When taken together, these behaviors may mitigate inflammation associated with various chronic diseases, which is of particular importance as very few smokers successfully quit smoking.
Multiple Glycolytic Enzymes Are Tightly Bound to the Fibrous Sheath of Mouse Spermatozoa

The fibrous sheath is a cytoskeletal structure located in the principal piece of mammalian sperm flagella. Previous studies showed that glyceraldehyde 3-phosphate dehydrogenase, spermatogenic (GAPDHS), a germ cell-specific glycolytic isozyme that is required for sperm motility, is tightly bound to the fibrous sheath. To determine if other glycolytic enzymes are also bound to this cytoskeletal structure, we isolated highly purified fibrous sheath preparations from mouse epididymal sperm using a sequential extraction procedure. The isolated fibrous sheaths retain typical ultrastructural features and exhibit little contamination by axonemal or outer dense fiber proteins in Western blot analyses. Proteomic analysis using peptide-mass fingerprinting and MS/MS peptide fragment ion matching identified GAPDHS and two additional glycolytic enzyme subunits, the A isoform of aldolase 1 (ALDOA) and lactate dehydrogenase A (LDHA), in isolated fibrous sheaths. The presence of glycolytic enzymes in the fibrous sheath was also examined by Western blotting. In addition to GAPDHS, ALDOA, and LDHA, this method determined that pyruvate kinase is also tightly bound to the fibrous sheath. These data support a role for the fibrous sheath as a scaffold for anchoring multiple glycolytic enzymes along the length of the flagellum to provide a localized source of ATP that is essential for sperm motility.
Synthesis, Characterization, and Ammonia Adsorption Properties of Mesoporous Metal–Organic Framework (MIL(Fe))–Graphite Oxide Composites: Exploring the Limits of Materials Fabrication

Composites of MIL-100(Fe) and graphite oxide (GO) were prepared with various ratios of the two components and tested for ammonia removal in dynamic conditions. The initial and exhausted samples were characterized by X-ray diffraction, nitrogen adsorption, thermal analysis, Fourier Transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy. The results indicate that the formation of well-defined MIL-100(Fe)/GO composites is not favored. This is linked to the specific geometry of MIL-100(Fe). The attachment of the GO carbon layers to the spherical cages of MIL-100(Fe) (via coordination between the oxygen groups of GO and the metallic sites of the metal–organic framework) prevents the proper formation of the MIL-100(Fe) structure. Therefore, the composite with the highest GO content has a lower porosity and smaller ammonia adsorption capacity than those calculated for the physical mixture of MIL-100(Fe) and GO. The main mechanism of ammonia retention is via Bronsted interactions between ammonia and the water molecules present in MIL-100(Fe). Nevertheless, the presence of excess water in the system lowers the acidity of the MIL material, and consequently causes a decrease in the ammonia adsorption. The Lewis interactions between ammonia and the metal centers in MIL also take place during the adsorption process.
Transient muscarinic and glutamatergic stimulation of neural stem cells triggers acute and persistent changes in differentiation

While aberrant cell proliferation and differentiation may contribute to epileptogenesis, the mechanisms linking an initial epileptic insult to subsequent changes in cell fate remain elusive. Using both mouse and human iPSC-derived neural progenitor/stem cells (NPSCs), we found that a combined transient muscarinic and mGluR1 stimulation inhibited overall neurogenesis but enhanced NPSC differentiation into immature GABAergic cells. If treated NPSCs were further passaged, they retained a nearly identical phenotype upon differentiation. A similar profusion of immature GABAergic cells was seen in rats with pilocarpine-induced chronic epilepsy. Furthermore, live cell imaging revealed abnormal de-synchrony of Ca(++) transients and altered gap junction intercellular communication following combined muscarinic/glutamatergic stimulation, which was associated with either acute site-specific dephosphorylation of connexin 43 or a long-term enhancement of its degradation. Therefore, epileptogenic stimuli can trigger acute and persistent changes in cell fate by altering distinct mechanisms that function to maintain appropriate intercellular communication between coupled NPSCs.
Synthesis and reaction of 2,3-diazabicyclo[2.2.1]hept-5-ene

Abstract The first synthesis of 2,3-diazabicyclo[2.2.1]hept-5-ene is reported. The generation of this molecule is facilitated by the isolation of the bis-carboxylate salt formed on hydrolysis of the corresponding biscarbamate. The retro-Diels-Alder generation of diimide and cyclopentadiene is explored.
Outpatient pain predicts subsequent one-year acute health care utilization among adults with sickle cell disease.

Context Patient demographic and clinical factors have known associations with acute health care utilization (AHCU) among patients with sickle cell disease (SCD), but it is unknown if pain measured predominantly in an outpatient setting is a predictor of future AHCU in patients with SCD.
Sex differences in college student-teacher interactions: Fact or fantasy?

On-site observations analyzing student-teacher interaction for 50 college classes, matched by level, subject, and teacher's sex, revealed no difference in number and type of interactions in which male and female students participated. In female-taught classes, style differences were found: Male students' interactions were characterized by more student-teacher exchanges than females' interactions. From student questionnaires, differences in office visitation patterns were revealed, showing an apparent relationship to sex: Female students visited more female than male instructors. However, closer examination showed the student's major to be the key variable influencing visitation patterns. Results point to the need for testing a variety of variables in addition to sex before drawing conclusions about sex-related behavior.
The Stripping Cowboy Music, Medium, and Movement in the Male Strip Show(s)

The cowboy is undoubtedly one of the most iconic masculine symbols of the 20th century. Film, television, and music present the cowboy figure in many forms and styles continuously attracting audiences with voyeuristic interest, erotic fantasy, and physical desire. Media has shaped the cowboy image into both a symbol that is idolized, sexualized, and fantasized over in sexual performance spaces. These archives offer unforgettable examples of “the good, the bad, and the sexy” cowboy. As a result of such representations, the cowboy has become one of the most popular characters performed in the male strip show.
Response Effects in a Network Survey

A reverse record check study was conducted to measure the response effects in a network survey designed to locate a rare population subgroup. In this field experiment, diagnosed cancer patients and...
Seasonal and interannual variability in primary production and particle flux at Station ALOHA

Abstract A 5-year time-series study of primary production and euphotic-zone particle export in the subtropical North Pacific Ocean near Hawaii (Sta. ALOHA, 22°45′N, 158°W) with measurements collected at approximately monthly intervals has revealed significant variability in both ecosystem processes. Depth-integrated (0–200 m) primary production averaged 463 mg C m−2 day−1 (s = 156, n = 54) or 14.1 mol C m−2 year−1. This mean value is greater than estimates for the North Pacific Ocean gyre made prior to 1984, but conforms to data obtained since the advent of trace metal-clean techniques. Daily rates of primary productivity at Sta. ALOHA exhibited interannual variability including a nearly 3-year sustained increase during the period 1990–1992 that coincided with a prolonged El Nifio-Southern Oscillation (ENSO) event. Export production, defined as the particulate carbon (PC) flux measured at the 150 m reference depth, also varied considerably during the initial 5 years of the ongoing field experiment. The PC flux averaged 29 mg C m−2 day−1 (s = 11, n = 43) or 0.88 mol Cm−2 year−1. A 5-fold variation between the minimum and maximum fluxes, measured in any given year, was observed. During the first 3 years of this program (1989–1991), a pattern was resolved that included two major export events per annum one centered in late winter and the other in late summer. After 1991, export production exhibited a systematic decrease with time during the prolonged ENSO event. When expressed as a percentage of the contemporaneous primary production, PC export ranged from 2 to 16.9%, with a 5-year mean of 6.7% (s = 3.3, n = 40). Contrary to existing empirical models, contemporaneous primary production and PC flux were poorly correlated, and during the ENSO period they exhibited a significant inverse correlation. This unexpected decoupling of particle production and flux has numerous implications for oceanic biogeochemical cycles and for the response of the ocean to environmental perturbations.
Thyroid hormone inhibition of synaptosome amino acid uptake and protein synthesis.

— 3,3′,5-Triiodothyronine (T3) inhibited L-[14C]leucine uptake into synaptosomes. Inhibition was competitive with a Ki of 3.1 × 10−5m. Hofstee plot revealed an inverted hyperbolic curve suggestive of a two carrier or carrier plus diffusion mediated system for amino acid uptake. Both the carrier mediated and diffusional components were inhibited by thyroid analogues. l-Thyroxine and analogues inhibited the incorporation of l-[14C] leucine into cerebral synaptosome protein. At 50 μm, the triiodo-compounds were more inhibitory than tetraiodo->3,5-triiodo-l-thyronine >3,3′,5-triiodothyropro-pionic> l-thyroxine >3,5-diiodo-l-tyrosine. Thyroid analogue inhibition was not seen in liver or brain mitochondrial protein synthesis. 3,3′,5-Triiodothyronine had no effect on respiratory control or 2,4-DNP stimulated synaptosome respiration supported by malate plus pyruvate. Ouabain did not inhibit [14C]leucine uptake into adult synaptosomes. There was synergistic inhibition of synaptosome protein synthesis by thyroid analogues in the presence of 0.2 mm-ouabain. 3,3′,5-Triiodothyronine had no effect on synaptosome fraction ATPase or Na-K ATPase. Addition of T3 induced further inhibition of synaptosome protein synthesis in the presence of either chloramphenicol (100μm) or cycloheximide (50μg/ml). [14C]Glycine uptake and incorporation into synaptosome protein was inhibited by 3,3′,5-triiodothyronine. There was no inhibition of [14C]proline uptake or incorporation. The above evidence and kinetic data strongly favor a selective competitive block in amino acid transport at the synaptosome membrane leading to a decreased rate of protein synthesis.
The Organizational Effectiveness Menu: A Device for Stakeholder Assessment

A procedure to assess organizational effectiveness is proposed in this paper. An OE “menu” of optionsis set out by which organizational performance can be measured. By using such a menu, managers’ decision making, planning, and communicating with internal and external constituencies can be enhanced.
An algorithm for segment-dragging and its implementation

Given a collection of points in the plane, pick an arbitrary horizontal segment and move it vertically until it hits one of the points (if at all). This form ofsegment-dragging is a common operation in computer graphics and motion-planning, it can also serve as a building block for multidimensional data structures. This note describes a new approach to segment-dragging which yields a simple and efficient solution. The data structure requiresO(n) storage andO(n logn) preprocessing time, and each query can be answered inO(logn) time, wheren is the number of points in the collection. The method is best understood as the end result of a sequence of transformations applied to a simple but inefficient starting solution.
Enhancement of oxygen adsorption on silicon following electron irradiation

Abstract While electron-stimulated adsorption of oxygen on silicon during electron irradiation is well known, we here report enhanced adsorption of oxygen on both crystalline and hydrogenated amorphous silicon following electron irradiation. The adsorption enhancement is proportional to the energy dissipation at the irradiated surface, and thus is inversely related to the beam energy. Electronic excitation processes are thought to cause bonding changes and thus enhanced adsorption.
Statistics of Non-Gaussian Scattered Light

The statistical distribution of the scattered light intensity is studied theoretically and experimentally for systems where $〈N〉$, the average number of particles in the scattering volume, is small. An expression is obtained for the intensity distribution for the case of a uniformly illuminated scattering volume and the moments are obtained for an arbitrary illumination profile. Calculated moments are compared with those measured for dilute solutions of polystyrene spheres.
The ordered field property and a finite algorithm for the Nash bargaining solution

This note proves that the two person Nash bargaining theory with polyhedral bargaining regions needs only an ordered field (which always includes the rational number field) as its scalar field. The existence of the Nash bargaining solution is the main part of this result and the axiomatic characterization can be proved in the standard way with slight modifications. We prove the existence by giving a finite algorithm to calculate the Nash solution for a polyhedral bargaining problem, whose speed is of orderBm(m-1) (m is the number of extreme points andB is determined by the extreme points).
Air embolus risk with glass versus plastic syringes: in vitro study and implications for neuroangiography.

PURPOSE: To assess syringe use among neuroangiographers and evaluate air emboli produced with glass and plastic syringes. MATERIALS AND METHODS: Questionnaires on syringes use were sent to 100 members of the American Society of Neuroradiology (ASNR). An in vitro system counted emboli during injections of contrast material and saline solution with either glass or plastic syringes. At Doppler sonography, an embolic signal was defined as the power of the reflected amplitude with auditory and visual confirmation. RESULTS: Of 62 respondents, 11.3% used glass syringes exclusively and 80.6% used plastic exclusively. Glass breakage was experienced by 72.5%, and 40% of them recalled an injury associated with such a breakage. No statistically significant difference was found between glass and plastic syringes for introduction of air emboli, though two outlying values represented larger numbers of emboli in the group with plastic syringes and contrast material. CONCLUSION: No reason for the continued use of glass sy...
High-energy electron irradiation and B coordination in Na2O-B2O3-SiO2 glass

The effects of high-energy electron irradiation and the fractions of B atoms in particular sites in a Na borosilicate glass have been studied using time resolved electron energy loss spectroscopy in a scanning transmission electron microscope. Conversion of B atoms from the tetrahedral into trigonal coordination under irradiation has been observed. A mechanism for high-energy electron irradiation processes in Na borosilicate glasses is proposed based on the evolution of the near-edge fine structures of the B K, Si L and O K-edges.
Expression of assayable residual stem cell damage in erythroid differentiation.

In rodents, residual damage is inducible in hematopoietic stem cells by exposure to ionizing radiation or alkylating agents. This damage can be assayed in mice by transferring bone marrow into lethally irradiated syngeneic recipients and subsequently measuring the incremental increase of 5-(125I)iodo-2′-deoxyuridine incorporation in spleens. In this study, bone marrow from mice treated 3 weeks previously with Methylnitrosourea (50 mg/kg) or 450 rad was injected into recipients in order to determine possible residual effects of treatment on erythroid cell differentiation following stem cell seeding. Such effects were detected by a reduced amount of59Fe incorporation into spleens, thus indicating transfer of residual stem cell damage to differentiating cells.
Activity, startle magnitude, and prolonged food and water deprivation: Two further failures to duplicate

Studies from one laboratory have shown deprivation-induced attenuation of startle response magnitudes, but another laboratory has reported failures to show any relationship between these variables. In an attempt to locate possible procedural contributions to this discrepancy in outcomes, our Experiment 1 involved 20 massed startle-stimulus presentations (30-sec ISI) to rats that had gone either 43 h or 1 h since eating (80% body weights equated for groups). Experiment 2 entailed spaced presentations (four trials per five bidaily sessions, 20-min ISI) to rats that had gone either 43 h or 1 h since drinking (80% weights also equated). Activity prior to, during, and after startle presentations also was recorded. Although group startle magnitudes differed on some trial blocks of both experiments, these differences were not systematically related to either of the deprivation conditions. Mean activity level was sensitive to startle-stimulus presentations, and showed systematic trial-block rates of decline for periods prior to, during, and following startle presentations that were identical for all groups.
Response of sliding structures with restoring force to stochastic excitation

Abstract The stochastic response of a rigid structure with a restoring force resting on a frictional foundation and excited by stationary or evolutionary white noise is studied analytically and by Monte Carlo simulation. The degree of accuracy and range of applicability of the following three analytical methods is established: (1) Equivalent Linearization Method, (2) stationary solution of the Fokker-Planck equation and (3) direct closed form stochastic linearization of a viscoplasticity model. It is demonstrated that the Viscoplasticity Model is a very accurate and effective tool for studying sliding base isolation systems for all levels of excitation and any value of the coefficient of friction μ. However, the Equivalent Linearization Method also gives accurate predictions even for relatively low levels of excitation when the coefficient of friction is less than 0.1.
The Performance of Nested Logit Models When Welfare Estimation Is the Goal

In this paper we examine the performance of nested logit models in the face of two specification errors. The first specification error arises when a nested logit model is appropriate, but the wrong nesting structure is chosen. The second specification error occurs when the underlying stochastic process is not consistent with nested logit. Particular attention is placed upon the impact that these errors can have on welfare predictions. Monte Carlo experiments are used, together with analytical results, to examine the resulting bias to welfare estimates. In addition, we explore the value of alternative model selection criteria in choosing nesting structures.
Interleukins and Atherosclerosis: A Dysfunctional Family Grows

Atherosclerosis is driven by the release of cytokines from macrophages, and the β isoform of interleukin-1 (IL-1β) is a prime suspect in disease progression. Freigang et al. (2013) now suggest that IL-1α, a close relative, is selectively induced by fatty acids independent of the inflammasome to promote vascular inflammation.
High-dose combination alkylating agents with autologous bone-marrow support in patients with breast cancer: preliminary assessment of DNA damage in individual peripheral blood lymphocytes using the single cell gel electrophoresis assay

The single cell gel (SCG) assay is a sensitive electrophoretic technique for detecting the presence of DNA single strand breaks and alkali-labile damage in individual cells. This technique was used to evaluate the levels of DNA damage in cryopreserved peripheral blood lymphocytes (PBLs) from 11 breast cancer patients treated with high doses of cyclophosphamide and cisplatin and provided autologous bone marrow transplantation after treatment. PBL specimens for the SCG study were obtained just prior to treatment, following the administration of cyclophosphamide and cisplatin for 2 days, and upon lymphocytic recovery. Based on a concurrent analysis of DNA damage in cryopreserved and non-cryopreserved PBL samples from three patients, the mean level of DNA migration or the dispersion of damage among cells was not affected by the process of cryopreservation. The pre-treatment samples of several patients contained PBL with increased levels of DNA damage, presumably reflecting persistent DNA damage induced by previous treatment regimens. Chemotherapy resulted in a significant but variable increase in DNA damage in PBL samples from all patients. In this limited study, the level of damage did not correlate with serum levels of cyclophosphamide or with lymphocyte toxicity. Among the post-treatment samples, increased levels of DNA damage were absent in most but not all patients. The presence of damaged cells in the post-treatment samples may be indicative of an inadequate therapy regimen or of DNA damage resulting from non-therapy related processes. Because of its simplicity and short processing time, the SCG assay can be used to evaluate levels of DNA damage during the course of therapy, allowing the dose schedule to be altered to achieve a desired effect level.
Ecological Group Work Applied to Schools

This article underscores the value of school counselors connecting their group work practice with ecological concepts of context, collaboration, interconnection, social system maintenance, meaning-making, and sustainability (Conyne & Cook, 2004; Conyne, Crowell, & Newmeyer, in press). The authors elaborate ecological group work (Bemak & Conyne, 2004) applied to the schools and in keeping with the ASCA national model, highlighting five successively complex levels of ecological group work involvement: (1) Student Group Level, (2) Classroom Group Level, (3) School Personnel Role Group Level, (4) Whole System Group Level, and (5) School-Community Group Level.
Effects of Tactical Navigation Display Modality on Navigation Performance, Situation Awareness, and Mental Workload:

A tactical navigation task was performed in a virtual environment by 14 young male U.S. Army Soldiers using seven navigation display modalities to convey waypoint information. Among the seven exper...
W/age bias in worker displacement: how industrial structure shapes the job loss and earnings decline of older American workers

Abstract This paper examines age differences in patterns of worker displacement and employment and earnings changes of displaced workers. Data from the 1998 Displaced Worker Supplement (DWS) of the Current Population Survey (CPS) indicate that older displaced workers possessed higher weekly wages than did younger workers at the time of their displacement. Moreover, older displaced workers suffered greater amounts of earnings loss than did younger displaced workers. Older workers, more often than younger workers, were displaced from jobs in the goods-producing sector. We attribute this age and industry difference in displacement to the higher earnings premium of older workers in the goods producing sector relative to the earnings premium of older workers in the service-producing sector. The age bias against older displaced workers may be viewed as part of social structural changes in the economy that have reduced the wage premium of the more expensive age segment of the workforce within industries that may economically benefit the most.
Comparison of microsomal inducer pretreatment on the in vitro α-hydroxylation and mutagenicity of N-nitrosopyrrolidine in rat and hamster liver

The effect of modifiers of liver mixed function oxidase activity on the in vitro alpha-hydroxylation and mutagenicity of N-nitrosopyrrolidine (NPYR) has been examined in rats and hamsters. Hamster post-mitochondrial supernatants were able to convert NPYR to a mutagen more efficiently than rat preparations under all conditions studied. Aroclor 1254 pretreatment caused the greatest increase in mutagenic activity in both species while phenobarbital and 3-methylcholanthrene pretreatment gave intermediate values when compared to uninduced preparations. Microsomal alpha-hydroxylation of NPYR was induced by Aroclor 1254 pretreatment in both species. Pretreatment with 3-methylcholanthrene increased alpha-hydroxylation in hamsters but decreased it in rats. Phenobarbital pretreatment only slightly increased microsomal alpha-hydroxylation in either species. When microsomal alpha-hydroxylation rates were expressed per gram wet weight of liver, better agreement between rates of alpha-hydroxylation and mutagenicity in phenobarbital pretreated animals was obtained since inducer associated changes in total microsomal protein content were taken into account. An example of differential induction of an activation pathway (alpha-hydroxylation) and a degradative pathway (aldehyde dehydrogenase) is presented to illustrate a potential source of error in the interpretation of metabolic data obtained from post-microsomal supernatants and whole animal studies.
The Question Of Sulfates A Conference Summary

On April 13 and 14,1978, the Mid-Atlantic States’ Section of the Air Pollution Control Association sponsored a technical conference in Philadelphia on the problem of atmospheric sulfates. The papers focused chiefly on sulfates in the eastern United States. Researchers from many governmental and private laboratories presented results from recent studies which indicated a shifting in the priorities concerning various environmental impacts of sulfate. The concern over the health effects of sulfates has lessened, while interest in the relationships between sulfates, visibility, and acid precipitation has increased.
MICROBIOLOGICAL EVALUATION OF GROUND BEEF CONTAINING MECHANICALLY DEBONED BEEF

Ground beef chub packs containing 0, 5, 10, 15, 20, 25 or 30% mechanically deboned beef (MDB) were examined for aerobic plate counts (5°C and 35°C), coliforms, Escherichia coli, Staphylococcus aureus, Clostridium perfringens and salmonellae after storage at two temperatures for various times. Chub packs were stored at –1.1°C for 0, 6, 12, 18 and 24 days and at –23.3°C for 2, 4 and 6 months. Isolation of Salmonella enteritidis serotype rubislaw from the pure MDB used in product formulation and from two (1%) of the chub packs containing MDB indicated that a large number of commercial samples of MDB from various sources should be evaluated. However, the aerobic plate counts, coliform, E. coli, S. aureus and C. perfringens counts in the seven formulations indicated that the addition of MDB to ground beef at levels up to 30% would not affect microbiological safety or shelf-life if the product were formulated and stored according to the procedures outlined in this study.
Leadership Positions and Sex Role Stereotyping among Gifted Children.

Forty-nine boys and 48 girls in grades four through six who were attending a program for intellectually gifted students were the subjects in this study. They were presented with a list of 34 leadership positions and asked whether men, women, or either sex could hold that position. Analysis of the findings indicates that boys tend to have more traditional sex role stereotypes than do girls. Implications for parents and teachers are discussed.
Optics programs at University of Massachusetts/Lowell: the role of a state university in a high-tech state

Optics education of both the undergraduate and graduate levels available at the Department of Physics and Applied Physics at the University of Massachusetts-Lowell is discussed. A brief history and motivation for establishing the program is presented. Also included are the undergraduate Optics Option curriculum, course requirements for the M. S. and Ph.D. degrees and a selection of both M.S. and Ph.D. dissertation titles.
824 THE VARYING CLINICAL SPECTRUM OF PRESENTATION OF BURKITT'S LYMPHOMA IN CHILDREN

Burkitt's lymphoma is a rare neoplasm in children and has varied clinical presentations and course. Six Caucasion children between the ages of 5 and 18 years were studied at Henry Ford Hospital. Five were male and one was female. Five out of six of the patients were initially diagnosed as having gastroenteritis. Their initial presentation was abdominal pain, vomiting and distention. Two of the children had evidence of acute intestinal obstruction at the time of diagnosis. Leukemic transformation (4/6), meningeal involvement (3/6), testicular involvement (1/6), bilateral ovarian involvement with ascites and hypomenorrhea (1/6), monarticular arthritis with bone involvement (1/6), massive pleural effusion (1/6), submandibular lymphadenopathy (1/6) were other clinical signs present at the time of diagnosis. Two out of six achieved complete remission on chemotherapy and are long-term survivors at 70 months and 66 months. Serum lactic dehydrogenase (LDH) levels closely correlated with recurrence and extent of tumor mass. Both patients who had complete remissions had only localized disease and had LDH levels below 400 IU/cc. Metabolic complications encountered consisted of uric acid nephropathy (1), hypocalcemia and hyperphosphatemia (2) with uncontrolled seizures. Morphological, cytochemical and ultrastructural studies were performed to confirm the pathological diagnosis.
Distribution of alkanes in normal and atherosclerotic rabbit aortas.

Abstract Hydrocarbon fractions were isolated from lipid extracts of normal and atherosclerotic rabbit aortas. They were analyzed by thin-layer chromatography and gas-liquid chromatography. The principal constituents in both normal and atherosclerotic tissue consisted of a homologous series of n -alkanes (C 18 C 34 ). Also detected were homologous series of iso and anteiso -alkanes, dimethyl branched alkanes and squalene. Although the hydrocarbon composition of both normal and sclerotic aortas is essentially the same, the amount and proportion of each hydrocarbon varied.
Age- and sex-dependent alterations in protein kinase C (PKC) and extracellular regulated kinase 1/2 (ERK1/2) in rat myocardium.

Abstract Cardiovascular morbidity and mortality increase significantly with advancing age, with proportionally higher rates occurring in aged women when compared to aged men. The signaling alterations responsible for age-related reductions in ischemic stress reserves, particularly in aged women, are poorly understood. Accordingly, we sought to determine whether alterations in the cellular location and formation of specific protein kinase C (PKC)-extracellular regulated1/2 (ERK1/2) signaling modules (SMS) might provide insight into known age- and sex-related differences in cardiovascular disease outcomes. Cytosolic (Cyto), mitochondrial (Mito) and nuclear (Nuc) fractions were isolated from left ventricles of male (M) and female (F) adult (6mo), castrated or aged (23mo) F344 rats by centrifugation. Western blotting was used to assess PKC (α, δ, ɛ), p-ERK1/2 and p-Bad(Ser 112 ) levels, and immunoprecipitation to assess PKC-ERK1/2 SMS. Cyto-PKCα levels increased with age ( p p p p p p 112 ) levels were decreased with age in both M and F. Differences in sex hormone status could not fully account for observed age-related differences in PKC. Collectively, our results provide novel evidence for age and sex-related differences in the magnitude and distribution of cardiac PKC-ERK1/2 SMS consistent with previously described pathological and protective phenotypes, respectively.
Kinetic simulation of methane hydrate formation and dissociation in porous media

Abstract The vast amount of hydrocarbon gas deposited in the earth's crust as gas hydrates has significant implications for future energy supply and global climate. A 3-D simulator for methane hydrate formation and dissociation in porous media is developed for designing and interpreting laboratory and field hydrate experiments. Four components (hydrate, methane, water and salt) and five phases (hydrate, gas, aqueous-phase, ice and salt precipitate) are considered in the simulator. The intrinsic kinetics of hydrate formation or dissociation is considered using the Kim–Bishnoi model. Water freezing and ice melting are tracked with primary variable switch method (PVSM) by assuming equilibrium phase transition. Mass transport, including two-phase flow and molecular diffusions, and heat transfer involved in formation or dissociation of hydrates are included in the governing equations, which are discretized with finite volume difference method and are solved in a fully implicit manner. The developed simulator is used here to study the formation and the dissociation of hydrates in laboratory-scale core samples. In hydrate formation from the system of gas and ice ( G + I ) and in hydrate dissociation systems where ice appears, the equilibrium between aqueous-phase and ice ( A – I ) is found to have a “blocking” effect on heat transfer when salt is absent from the system. Increase of initial temperature (at constant outlet pressure), introduction of salt component into the system, decrease of outlet pressure, and increase of boundary heat transfer coefficient can lead to faster hydrate dissociation.
The neighboring group effect of fluorine in the tritium labeling of organic substrates with [Cp*(PMe3)IrMe(CH2Cl2)]+[BArf]−, a cationic iridium(III) complex

The cationic Ir(III) complex, [Cp*(PMe3)IrMe(CH2Cl2)][BArf] (1, Cp*=η5-C5Me5, BArf=MeB(C6F5)3), has been shown to be a useful reagent in the tritium and deuterium labeling of organic substrates. During a recent reaction of 1 with a fluorinated molecule, we observed an unusually high incorporation of tritium ortho to the aromatic fluorines. To probe whether this was an isolated incident or a more general phenomenon, we have investigated the application of 1 towards the tritiation of simple fluorinated organic substrates. Our results indicate that aromatic fluorine indeed does exhibit a neighboring group effect in terms of directing ortho H/T exchange. The directing influence appears to be at least as strong as the hydroxyl moiety reported in previous works. Copyright © 2006 John Wiley & Sons, Ltd.
Resolution and Structural Transitions of Elongated States of Ubiquitin

Electrospray ionization, combined with two-dimensional ion mobility spectrometry and mass spectrometry, is used to produce, select, and activate distributions of elongated ions, [M+11H]11+ to [M+13H]13+, of ubiquitin. The analysis makes it possible to examine state-to-state transitions for structural types, and transition diagrams associated with the efficiencies of structural changes are presented. The +11 and +12 charge states can form four resolvable states while only one state is formed for [M+13H]13+. Some conformations, which appear to belong to the same family based on mobility analysis of different charge states, undergo similar transitions, others do not. Activation of ions that exist in low-abundance conformations, having mobilities that fall in between sharp peaks associated with higher abundances species, shows that the low-abundance forms undergo efficient (∼90 to 100%) conversion into states associated with well-defined peaks. This efficiency is significantly higher than the ∼10 to 60% efficiency of transitions of structures associated with well-defined peaks. The formation of sharp features from a range of low-intensity species with different cross sections indicates that large regions of conformation space must be unfavorable or inaccessible in the gas phase. These results are compared with several previous IMS measurements of this system as well as information about gas-phase structure provided by other techniques.
Effect of cyclosporine on rubella virus-specific immune responses in chronic progressive multiple sclerosis.

Abstract Cyclosporine A (CsA) has been used in putative autoimmune diseases after sensitization to unknown antigens. We have previously shown that CsA prevented continued activation of T-cells in chronic progressive multiple sclerosis (CPMS) patients. The current study was undertaken to determine whether CsA, CsA and prednisone (CsA + P) could suppress immune responses to a common recall antigen. Serum antibody levels were higher in all CPMS patients than age-matched normal controls. However, rubella antibody titers in the CsA or CsA + P groups were no different from a placebo-treated CPMS patient group. The lymphocyte responses to inactivated rubella virus of CsA and CsA + P-treated CPMS patients were lower than placebo and control but not statistically different. Therapy with bot CSA and CSA + P was associated with significantly lower panel mixed leukocyte responses and Ta1 expression than in the placebo-treated group; CD3, CD4, CD8 antigen expression and active rosette formation by T-cells were similar for the three CPMS groups. These results suggest that while CsA exerts measurable effects on non-specific indicators of cellular immunity in CPMS patients, it may not be as effective in suppressing pre-existent specific immune responses.
Mitochondrial complex III: An essential component of universal oxygen sensing machinery?

Oxygen is necessary for the survival of mammalian cells. In order to maintain adequate cellular oxygenation, mammals have evolved multiple acute and long-term adaptive responses to hypoxia. These include hypoxic increases in erythropoiesis, pulmonary vasoconstriction and carotid body neurosecretion. Collectively, these responses help maintain oxygen homeostasis as oxygen levels remain scarce. There are multiple effectors proposed to underlie these diverse responses to hypoxia including PHD2, AMPK, NADPH oxidases, and mitochondrial complex III. Here I propose a model wherein complex III is integral to oxygen sensing in regulating diverse response to hypoxia.
Reduction in inflammation following blockade of CD18 or CD29 adhesive pathways during the acute phase of a spirochetal-induced colitis in mice.

Colitis develops in mice infected with Brachyspira (Serpulina) hyodysenteriae. Numerous granulocytes (PMNs) are evident in cecal tissue sections 24-48 h post-infection. The role of PMNs was assessed by utilizing monoclonal antibodies specific for CD18 or CD29 to block PMN recruitment. Macroscopic lesions were less severe in mice treated with either monoclonal antibody compared to lesions observed in isotype control-treated mice. While these monoclonal antibodies may inhibit extravasation of other leukocytes, the central role of PMNs was further demonstrated in that colitis was reduced following neutrophil depletion. There was less edema and epithelial erosions in ceca of mice receiving anti-Ly6G, -CD18 or -CD29 monoclonal antibody compared to mice receiving the control. Moreover, there was a significant reduction in PMN infiltration in tissues of mice treated with anti-CD18. The reduction in infiltrating PMNs did not result from downregulation of neutrophil chemoattractant MIP-2 expression in anti-CD18-treated mice. In contrast, PMN recruitment into the cecum was apparently CD29-independent. It is noteworthy that the number of PMNs observed in anti-CD18-treated mice was significantly higher than observed in non-infected mice. The data provide evidence for a threshold number of PMNs necessary for lesion development and indicate that CD18, but not CD29, adhesive pathways are crucial for PMN recruitment in bacterial colitis.
Wealth accumulation among U.S. immigrants: A study of assimilation and differentials

Abstract Data from the New Immigrant Survey are used to study wealth differentials among U.S. legal permanent residents. This study is unique in its ability to account for wealth held in the U.S. and that held abroad and yields several key findings. First, relative to immigrants from Western Europe, Australia, Canada, and New Zealand (who have median wealth similar to native born non-Hispanic whites), other immigrant groups have lower levels of total wealth even after accounting for permanent income and life course characteristics. Second, time in the U.S. is positively associated with the wealth of married immigrants, yet this relationship is not statistically significant for single immigrants. Third, differences in the means of measured characteristics between Western European immigrants and those from most other origin regions account for more than 75 percent of observed wealth disparities. However, for immigrants from Asia and from the Indian subcontinent, much of the wealth differential remains unexplained by these factors.
Fixed time constant AGC circuits

The generalized design of Automatic Gain Control (AGC) circuits that have constant settling time is described. Each of the major components of the AGC circuit is modeled and the criteria to obtain a gain settling time independent of the absolute gain is determined. The method developed works with arbitrary monotonic nonlinear functions in the gain control characteristic of the variable gain amplifier. Three AGC circuits are simulated at the behavioral level to show the benefits of the technique developed.
Policy-driven data dissemination for context-aware applications

Context-aware pervasive-computing applications require continuous monitoring of their physical and computational environment to make appropriate adaptation decisions in time. The data streams produced by sensors, however, may overflow the queues on the dissemination path. Traditional flow-control and congestion-control policies either drop data or force the sender to pause. When the data sender is sensing the physical environment, however, a pause is equivalent to dropping data. Instead of arbitrarily dropping data that may contain important events, we present a policy-driven data dissemination service named PACK, based on an overlay-based infrastructure for efficient multicast delivery. PACK enforces application-specified policies that define how to discard or summarize data flows wherever queues overflow on the data path, notably at the mobile hosts where applications often reside. A key contribution of our approach is to uniformly apply the data-stream "packing" abstraction to queue overflow caused by network congestion, slow receivers, and temporary disconnection. We present experimental results and a detailed application study of the PACK service.
Thermo-chemical structure in the mantle arising from a three-component convective system and implications for geochemistry

Abstract Numerical simulations are used to characterize structures and observational signatures of thermo-chemical convection with three component of differing densities nominally corresponding to regular mantle (the depleted Mid Oceanic Ridge Basalt (MORB) source), primitive mantle and recycled crust. Strong heterogeneity, similar to that observed in seismic tomography models, is generated near the CMB by sweeping of the highest density ‘recycled’ component into piles by convective downwellings. Meanwhile, the medium density ‘primitive’ material is widely dispersed by the convection and forms ‘blobs’. Two types of upwelling plumes are observed: large plumes arising from the top of dense piles and small-scale plumes arising from the base of the transition zone resembling seismic tomography images of upwelling plumes [Zhao, Earth Planet. Sci. Lett. 192 (2001) 251], although the origin of these plumes is unclear. The horizontal spectra of the seismic velocity had anomalies at different depths are most similar to tomographic models when dense basal piles are present. Comparing to geochemically-required residence times, the source of HIMU (this type of rock has high ratio of helium isotope anomaly) Ocean Island Basalt (OIB) is more likely to be dense ‘piles’, while lower mantle blobs have been proposed as a location of primitive material. Thus the combination of blob structures and deep mantle piles may be plausible way of simultaneously satisfying geochemical and seismological constraints on mantle structure.
Experimental Measurements of Subgrid Passive Scalar Anisotropy and Universality

An experimental study on the effects of passive scalar anisotropy on subgrid-scale (SGS) physics and modeling for Large-Eddy Simulations is performed across a turbulent wake flow generated by a heated cylinder. To obtain filtered and subgrid quantities at three different filter sizes the separation distance among probes in an array of four X-wire and four cold-wire probes is varied. We find that while the kinetic energy dissipation tensor approaches isotropy at small scales, the SGS scalar-variance dissipation remains anisotropic independent of filter scale in the presence of the scalar gradient. The eddy-diffusion model predicts, incorrectly, isotropic behavior. The nonlinear (or tensor eddy diffusivity) model reproduces the correct trends, but overestimates the level of scalar dissipation anisotropy. The model coefficients evaluated from matching global averages of real and modeled SGS dissipations are fairly uniform across the wake (universal), both for those associated with the SGS momentum field and the anisotropic scalar field.
Autonomous helicopter navigation during a tail rotor failure utilizing fuzzy logic

This paper presents a fuzzy controller capable of waypoint navigation under tail rotor failure on a small unmanned helicopter. Helicopters, or Vertical Takeoff and Landing (VTOL) vehicles, have shown great success in military, humanitarian, and commercial endeavors and their increased use as Unmanned Aerial Vehicles (UAVs) have brought up great concerns as to the safety of these vehicles. The presented controller offers navigation possibilities to a situation that would typically results in an autorotation (emergency landing without power) or crashed vehicle. This is most beneficial in situations where the terrain, safety, or security do not allow for landing. The concepts, as well as the implementation, of the controller along with simulation experiments are presented.
A challenge to Goliath

Megapublishers obligate librarians to buy hundreds of journals they do not need in order to access the journals their constituents actually read. The time has come to challenge this business model, which is unsustainable for the libraries.