cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamic Analysis of Elastic-Plastic Structures by Mode-Superposition and Equivalent Plastic Loads

Abstract A method is shown for the dynamic analysis of elastic-plastic structures by mode superposition and treating plastic strain as additional applied loads. This method reduces the elastic-plastic analysis to elastic analysis of the same structure with additional forces. In the elastic analysis, the modes of vibration and stiffness matrix are elastic and remain the same in all time steps. This eliminates the calculation of a new stiffness matrix for each time step and hence greatly reduces the amount of numerical computation. Dynamic elastic-plastic responses of an unsymmetrical portal frame were calculated as an illustration of this method. The elastic modes and stiffness matrix were calculated by the finite element method.
Demographic change and backlash: Identity politics in historical perspective:

Why are backlash politics so prevalent in the context of demographic change? And so that we may understand how to mitigate social conflict, what role do government and political actors play in thei...
Ubl4A is critical for mitochondrial fusion process under nutrient deprivation stress

Mitochondrial fusion and fission are dynamic processes regulated by the cellular microenvironment. Under nutrient starvation conditions, mitochondrial fusion is strengthened for energy conservation. We have previously shown that newborns of Ubl4A-deficient mice were more sensitive to starvation stress with a higher rate of mortality than their wild-type littermates. Ubl4A binds with the actin-related protein Arp2/3 complex to synergize the actin branching process. Here, we showed that deficiency in Ubl4A resulted in mitochondrial fragmentation and apoptosis. A defect in the fusion process was the main cause of the mitochondrial fragmentation and resulted from a shortage of primed Arp2/3 complex pool around the mitochondria in the Ubl4A-deficient cells compared to the wild-type cells. As a result, the mitochondrial fusion process was not undertaken quickly enough to sustain starvation stress-induced cell death. Consequently, fragmented mitochondria lost their membrane integrity and ROS was accumulated to trigger caspase 9-dependent apoptosis before autophagic rescue. Furthermore, the wild-type Ubl4A, but not the Arp2/3-binding deficient mutant, could rescue the starvation-induced mitochondrial fragmentation phenotype. These results suggest that Ubl4A promotes the mitochondrial fusion process via Arp2/3 complex during the initial response to nutrient deprivation for cell survival.
A Well-Organized Plаy: Symbolic Politics and the Effect of the Pro-Putin Rallies

The paper illustrates the government’s agility in response to opposition protests and the debacle of parliamentary elections. We explore the evolution of Kremlin strategies from a reliance on cooptation to more coercive strategies — a trend that continued after Putin’s election in March. These strategies were successful in mobilizing core voters, creating common identity among participants, and containing the electoral effects of the opposition protests. However, the government's strategy also embodied significant costs that are likely to have longer-term influences and did little to build a true movement of regime loyalists. The Kremlin’s rigid definition of both the symbols and rhetoric of Putinism left little room for participants to participate in the production of symbols and language. While the narratives imposed from above help Putin’s supporters to participate in political life in limited ways, they remain unable to formulate and articulate independent political positions. As a result, supporters remain highly dependent on the state. Deprived of the benefit of hearing supporters’ demands, this strategy also leaves the state in peril of further losing touch with its political base.
Hope for a stronger discipline of marketing

To a new generation of marketing scholars, Shelby Hunt might be identified with Resource-Advantage (RA) Theory, marketing theory books, or philosophy of science debates from the 1980s. This article...
Anthropologists on Interprofessional Health Education Teams: A Model from Upstate New York

This chapter describes the development of anthropologically-based innovations in health professional education in Syracuse, New York, and the extension of these innovations to a number of universities in upstate New York. The innovations included bringing together an action anthropological model of community based research with university-based work on the social determinants of health, and integrating these into health professional education. The chapter describes the development of the Community Action Research and Education (CARE) model, the use of the National Academies of Science framework for integrating the social determinant of health into health professional education, and efforts to suffuse both into the work of educators in upstate New York.
Parental dementia and subjective memory impairment in the health and retirement study.

To examine relationships between subjective memory impairment (SMI) and parental dementia among in older adults while considering the interactive influence of depressive symptoms, ethnicity, and ra...
Pit Shielding for Communication Satellite Ground-Terminal Antennas

Measurement of shielding provided for ground terminal antennas of satellite-to-ground communication links by one-sided differing geometry pits
125I in molecular hybridization experiments.

Publisher Summary The in vitro iodination of nucleic acids is employed in a wide diversity of applications, such as molecular hybridization experiments at both the molecular and cytological levels, nucleotide sequencing analysis by fingerprinting methods, and nucleic acid secondary structure analysis by iodination of non-base-paired cytosine residues. Under optimal conditions, the primary features of the nucleic acid iodination technique include (1) permitting the incorporation of relatively large amounts of a covalently bound, highly radioactive isotope into the molecular structure of nucleic acids and (2) avoiding extensive degradation or other deleterious alteration of the nucleic acid as a consequence of the labeling procedure. This chapter describes the role of 125I in molecular hybridization experiments. 125I is a highly advantageous isotope for use in molecular hybridization experiments. The principal advantage of 125I is its intrinsically high specific radioactivity because of its relatively short 60-day half-life. Because of this fact, it is possible to prepare labeled nucleic acids of high specific radioactivity by the introduction of limited quantities of 125I atoms. The incorporation and retention of iodine atoms in stable linkage with nucleic acids is strongly affected by (1) the pH of the reaction, (2) the ionic strength, (3) the nucleic acid concentration, (4) the time and temperature of the reaction, (5) the ratio of cytosine to iodide, (6) the concentration of iodide, and (7) the reaction termination step.
Liver transplantation and cirrhotomimetic hepatocellular carcinoma: Classification and outcomes

Liver transplantation has become the standard-of-care treatment for hepatocellular carcinoma (HCC) that falls within certain size and numerical criteria for patients with cirrhosis. Cirrhotomimetic (CMM) HCC is an uncommon growth pattern that infiltrates cirrhotic parenchyma, can become extensive in size, and can evade detection via radiological studies. Liver transplant outcomes for this type of HCC are not well reported but generally are considered to be poor. We wished to better describe this variant of HCC in explanted livers, derive a classification system for this tumor type, and assess the outcomes of liver transplantation for this tumor variant. All patients undergoing transplantation for HCC at a single center in 1996-2009 (358 patients) were retrospectively analyzed, and 26 patients exhibiting a CMM growth pattern were identified. We developed a classification system for this tumor growth pattern variant and determined patient and tumor-specific outcomes. We derived a classification schema for CMM HCC based on the tumor extent and cellular histopathology, with a clear cell pathology being associated with favorable outcomes. We noted 100.0% 3-year recurrence-free survival and 58.3% 5-year recurrence-free survival after transplantation for those patients with tumors confined to 1 lobe that had a clear cell pathology and 16.2% 3- and 5-year recurrence-free survival for those patients who did not meet these criteria. In conclusion, CMM HCC features were noted in 7% of the patients undergoing transplantation for HCC at our center, with favorable outcomes observed for inpatients with clear cell histology and growth involving less than or equal to 50% of the liver.
PHANTOM MAPS, COGROUPS AND THE SUSPENSION MAP

ABSTRACT The set Ph(X, Y) of pointed homotopy classes of phantom maps from X to Y admits a natural group structure if either Y is a grouplike space or X is a cogroup. In the present paper, the group structure on Ph(X,Y) is examined in the second case. (The first case was examined in an earlier paper.) The results in the two cases are similar—for instance, the group structure turns out to be abelian, divisible and independent of the grouplike structure on Y or the cogroup structure on X—but the techniques used to establish the results differ substantially in the two cases. In addition, a study of the map g*: Ph(X,Y1) → Ph(X,Y2) induced by a map g: Y1 → Y2 of grouplike spaces is initiated. A particularly interesting special case of this situation is the suspension map Ph(X, Y) → Ph(X, ΩσY) ≅ Ph(σX, σY) with Y a grouplike space.
Ferritin localization on the erythroblast cell membrane and ropheocytosis in hypersiderotic human bone marrows.

1. Preferential ferritin localization on specialized areas of the plasma membrane of erythroblasts with subsequent invagination into ropheocytotic vesicles, and the occurrence of ropheocytosis without ferritin being present in the vesicles, has been previously described. 2. In a study of bone marrows from patients with hypersiderosis we have confirmed the previous observations, but we frequently found nonferritin ropheocytosis in erythroblasts adjacent to ferritin laden reticulum cells. In addition, ferritin localization along the outer surface of erythroblasts was noted, particularly between continuous surfaces of two adjacent erythroblasts. Such intercellular accumulations of ferritin were not necessarily associated with a high ferritin content of adjacent cells. 3. These observations did not favor the hypothesis that ferritin iron was being transferred directly from reticulum cells to adjacent erythroblasts. It is suggested that the accumulation of ferritin along extended stretches of the erythroblast surface may signify that iron which is detached from siderophilin but not immediately transported across the cell membrane is incorporated into apoferritin produced on the cell membrane.
Cooperative Research Efforts Between Business Schools And The Private And Public Sectors: Frequency Of Occurrence And Outcomes

Recent criticisms of business education suggest that academia has fallen short in the areas of teaching, research and service. Cooperation between faculty, practitioners, and business research bureaus has been suggested as a means to enhance these outcomes of the educational process. Anticipated benefits include increased faculty research, affordable quality research for businesses, and greater exposure and credibility for business schools. This research documents the incidence of this type of cooperative effort in US business schools. The results suggest that these efforts are taking place and that faculty commitment is a key ingredient for success.
Comparison of Fluorescent Antibody with Cultural Technique for Isolation of Enteropathogenic Escherichia coli from Swine

In an investigation of hogs as possible reservoirs of human strains of enteropathogenic Escherichia coli (EEC), 92 six-month-old grain- and garbage-fed hogs were examined on the farm and again at the packing plant. Of the 331 specimens obtained by swabbing the rectum, cecum, and edible meat carcass of these hogs, 125 were presumptively positive for EEC when screened by the fluorescent-antibody (FA) technique. These “presumptive positive” specimens then underwent extensive bacteriological examination and complete serological typing. The FA technique proved to be an easier, simpler, and more economical procedure than culture when a large number of specimens were examined for possible EEC serogroups. It was found especially valuable for identification of multiple serogroups of EEC within a single specimen. It also appeared to be more sensitive than cultural examination, since results were not dependent on the presence of large numbers of organisms in the specimen, or even on their viability. However, the FA technique was found to be less specific than culture because of cross-reactivity with antigenically related Enterobacteriaceae when fluorescein-labeled antisera were used. Therefore, any specimen found positive on FA examination should be considered as presumptive positive until confirmed by bacteriological examination and complete serological study.
Neonatal narcotic addiction: 10 year observation.

During the 10-year period 1960 through 1969, 384 infants were born to 382 heroin addicted mothers. One hundred ninety (49.4%) of the infants were under 2,500 gm in weight. Seventy -seven (40%) of these were low weight for date infants. Two hundred fifty-nine (67.4%) of the total group of infants developed signs of withdrawal within the first 4 days of life. One hundred seventy-eight or 68.7% of these manifested signs severe enough to require treatment. Eighty-one infants had mild withdrawal signs which cleared without treatment. The 178 treated infants represented 46.3% of the entire group of heroin exposed infants. Our data indicated that there was a direct correlation between the length of maternal addiction and the occurrence of withdrawal signs in the infants; that with an increase of maternal intake of heroin, there was an increased incidence of neonatal withdrawal; and that the closer to delivery the last dose of heroin was taken, the higher and earlier was the occurrence of withdrawal signs in the neonate. Response to treatment with chlorpromazine was excellent. The incidence of congenital anomalies was no higher than in the general newbron population. Morphine and quinine could be demonstrated in the urine of the newborn infants within the first 24 hours of life. Fourteen infants (3.6%) died in the neonatal period; nine of these within the first 9 hours after birth. No evidence of Hyaline Membrane disease was found at autopsy in those that died in respiratory distress.
Can We Have Fries with That, Please? Nutrition and Physical Activities among College Students.

Obesity is a growing health and socioeconomic issue in the United States. College students are an important part of the alarming statistics involving weight gain. This study investigated how nutrition behaviors and physical activity modified students’ perceptions of body weight and nutrition knowledge. Furthermore, the study assessed gender and ethnicity as modifiers of nutrition behaviors, self-perception of body weight, and exercising habits among college students.
Cardiovascular Risk Factor Self-Assessment Program: Using the General Clinical Research Center to Provide a Clinical Experience for Third-Year Medical Students

An educational program at the University of Iowa has been designed to provide medical students with the opportunity to do a self-assessment of their personal risk factors for developing cardiovascular disease. The University of Iowa Hospital and Clinic's General Clinical Research Center (GCRC) provided the personnel and resources to work with students in small groups to allow them to experience the diagnostic testing that is a standard part of cardiovascular assessment procedures. This report presents preliminary data from the first 88 students to participate in the program.
Changes in the Midbrain-Rostral Forebrain Dopamine Circuitry in the Cocaine-Exposed Primate Fetal Braina.

To ascertain cocaine's effects in the fetus, we developed a nonhuman primate model in which pregnant monkeys were administered cocaine (3 mg/kg i.m.) or saline four times a day from day 20 through days 40-70 of a 165-day gestation. At the time of cesarean section, plasma levels of cocaine in fetal blood were 231 +/- 70 ng/ml. Fetal brains were examined using immunocytochemistry, in situ hybridization, receptor autoradiography, and nuclease protection assay analysis. No differences were found in the expression of tyrosine hydroxylase and dopamine receptor mRNAs by days 40-45 of gestation. However, by day 60 the midbrain of monkeys exposed to cocaine had significantly reduced expression of tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. Moreover, dopamine D1 and D2 receptor mRNAs were significantly elevated in the rostral forebrain as were D1 and D2 receptor binding sites in days 60-70 cocaine-exposed fetuses. Cocaine treatment from day 20 to days 60 and 70 of gestation also significantly increased the mRNA concentrations of dynorphin and enkephalin in the rostral forebrain. These findings suggest that in utero cocaine exposure has profound effects on the developing dopamine neurocircuitry.
“The Only Metaphor Left”: Colson Whitehead's Zone One and Zombie Narrative Form

This article explores Colson Whitehead's Zone One and the zombie narrative genre and outlines some of the ways each illuminates structural, generic, and aesthetic qualities in the other. Contrary to popular critical apologies, Zone One is largely a conventional zombie narrative that embraces the formal implications of the genre's tropes: notably the zombie figure itself, the barricade, and what this article calls soft and hard breaches. The zombie is a deconstructive and contagious anticharacter whose destabilizing role necessitates the construction of barricades that (1) protect the characters from infection and living death, (2) delineate a narrative space in which plot and character can develop, and (3) spatialize epistemological and aesthetic modes. Whereas hard breaches involve a narrative-threatening failure of diegetic barricades, the soft breach allows the zombie's destabilizing function to operate in the narrative space without posing a diegetic threat. Zone One's figures function similarly, as demonstrated by a formal and aesthetic analysis with specific regard to the novel's eponymous “survival space” and its constitutive barricade motif. Whitehead innovates in the genre by means of his own zombie contribution, the figure of the straggler, which facilitates more meditative thematic work than zombie narratives generally allow. This formal exploration of Zone One as a zombie narrative is meant to further zombie scholarship and to frame future critical work on the novel by contextualizing it in its genre.
A rapid pH-stat assay for phosphofructokinase and the forward reaction of phosphoglucose isomerase

Abstract Continuously recording pH-stat assays are deseribed for phosphofructokinase and the forward reaction of phosphoglucose isomerase. The validity of the assays is discussed in terms of stoichiometry, linearity, accuracy, and possible interference from undesired side reactions.
The Fletcher factor-prekallikrein deficiency: a diagnostic test which identifies heterozygotes.

Abstract A simple method for the detection of Fletcher factor-prekallikrein deficiency is described. The method is based on the necessity of this factor for the cold induced EACA acceleration of the thromboplastin time. It reveals both homozygotes and heterozygotes. To make the diagnosis specific, factor XII deficient plasma is needed.
Interleukin-18-induced Human Coronary Artery Smooth Muscle Cell Migration Is Dependent on NF-κB- and AP-1-mediated Matrix Metalloproteinase-9 Expression and Is Inhibited by Atorvastatin

The proliferation and migration of arterial smooth muscle cells (SMCs) are key events in the vascular restenosis that frequently follows angioplasty. Furthermore, SMC migration and neointimal hyperplasia are promoted by degradation of the extracellular matrix by matrix metalloproteinases (MMPs). Because we demonstrated previously that the proinflammatory and proatherogenic cytokine interleukin-18 (IL-18) stimulates SMC proliferation (Chandrasekar, B., Mummidi, S., Valente, A. J., Patel, D. N., Bailey, S. R., Freeman, G. L., Hatano, M., Tokuhisa, T., and Jensen, L. E. (2005) J. Biol. Chem. 280, 26263-26277), we investigated whether IL-18 induces SMC migration in an MMP-dependent manner and whether the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor atorvastatin can inhibit this response. IL-18 treatment increased both mRNA and protein expression of MMP9 in human coronary artery SMCs. Gel shift, enzyme-linked immunosorbent, and chromatin immunoprecipitation assays revealed a strong induction of IL-18-mediated AP-1 (c-Fos, c-Jun, and Fra-1) and NF-kappaB (p50 and p65) activation and stimulation of MMP9 promoter-dependent reporter gene activity in an AP-1- and NF-kappaB-dependent manner. Ectopic expression of p65, c-Fos, c-Jun, and Fra-1 induced MMP9 promoter activity. Specific antisense or small interfering RNA reagents for these transcription factors reduced IL-18-mediated MMP9 transcription. Furthermore, IL-18 stimulated SMC migration in an MMP9-dependent manner. Atorvastatin effectively suppressed IL-18-mediated AP-1 and NF-kappaB activation, MMP9 expression, and SMC migration. Together, our results indicate for the first time that the proatherogenic cytokine IL-18 induces human coronary artery SMC migration in an MMP9-dependent manner. Atorvastatin inhibits IL-18-mediated aortic SMC migration and has therapeutic potential for attenuating the progression of atherosclerosis and restenosis.
OBSERVATION OF A POMEAU-MANNEVILLE INTERMITTENT ROUTE TO CHAOS IN A NONLINEAR OSCILLATOR

For a driven nonlinear semiconductor oscillator which shows a period-doubling pitchfork bifurcation route to chaos, we report an additional route to chaos: the Pomeau-Manneville intermittency route, characterized by a periodic (laminar) phase interrupted by bursts of aperiodic behavior. This occurs near a tangent bifurcation as the system driving parameter is reduced by $\ensuremath{\epsilon}$ from the threshold value for a periodic window. Data are presented for the dependence of the average laminar length $〈l〉$ on $\ensuremath{\epsilon}$, and also on additive random noise voltage. The results are in reasonable agreement with the intermittency theory of Hirsch, Huberman, and Scalapino. The distribution $P(l)$ is also reported.
Formation and Recovery of Itaconic Acid from Aqueous Solutions of Citraconic Acid and Succinic Acid

The formation and recovery of itaconic acid (IA) from mixed aqueous solutions of citraconic acid (CA) and succinic acid (SA) has been developed as part of an overall process to produce itaconic acid via condensation of succinates with formaldehyde. The formation and recovery described here involves four steps: (1) removal of SA via crystallization, (2) isomerization of CA to IA at elevated temperature, (3) recovery of IA via crystallization, and (4) conversion of reaction byproducts back to CA. As part of the overall process, these steps facilitate recycling of unreacted species and reuse of byproducts, thus giving high overall yields. Itaconic and succinic acids are readily crystallized because of their low solubility relative to CA; lab-scale crystallization experiments gave high purity (99.8 wt % for SA; 99.4% for IA) crystalline solids after washing. Isomerization gave a maximum IA selectivity of 87% at 170 °C after 3 h reaction. The primary byproduct of isomerization, citramalic acid (CMA), and IA i...
Genomic islands and the ecology and evolution of Prochlorococcus

Prochlorococcus ecotypes are a useful system for exploring the origin and function of diversity among closely related microbes. The genetic variability between phenotypically distinct strains that differ by less that 1% in 16S ribosomal RNA sequences occurs mostly in genomic islands. Island genes appear to have been acquired in part by phage-mediated lateral gene transfer, and some are differentially expressed under light and nutrient stress. Furthermore, genome fragments directly recovered from ocean ecosystems indicate that these islands are variable among cooccurring Prochlorococcus cells. Genomic islands in this free-living photoautotroph share features with pathogenicity islands of parasitic bacteria, suggesting a general mechanism for niche differentiation in microbial species.
Computational modeling of elastic and plastic multiple cracks by the fundamental solutions

The fundamental solutions of elasticity are used to establish a numerical method for elastic and plastic multiple crack problems in two dimensions. The continuous distributions of the point forces, dislocations, and the plastic sources are used systematically to model the crack, non-crack boundary, and the plastic deformation. Use of these singularities are guided strictly by the physical interpretation of the problem. We adopt Muskhelishvili's complex variable formalism that facilitate the analytical evaluation of the integrals representing the continuous distributions of the singularities. The resulting numerical method is concise and accurate enough to be used for elastic and plastic multiple crack problems.
Multi-stage regression linear parametric models of room temperature in office buildings

Abstract Mathematical models of the heating, ventilation, and air conditioning (HVAC) components play an important role in control design and fault detection of the system. The work in this paper incorporates architectural parameters in linear parametric models of room temperature in office buildings. Specifically, we allow the physics-based autoregression moving average (pbARMAX) model to have a multi-stage structure in order to explicitly include the architectural parameters of the room in the model. Extensive measurements of the room temperature are used to develop and validate the multi-stage model. The resulting model can predict the temperature in different rooms accurately in both short-term and long-term. Over a period of four weeks, the predictions have a root mean squared error less than 0.10 with a coefficient of determination larger than 0.99.
Neural basis for sentence comprehension: grammatical and short-term memory components.

We monitored regional cerebral activity with BOLD fMRI while subjects were presented written sentences differing in their grammatical structure (subject-relative or object-relative center-embedded clauses) and their short-term memory demands (short or long antecedent-gap linkages). A core region of left posterior superior temporal cortex was recruited during all sentence conditions in comparison to a pseudofont baseline, suggesting that this area plays a central role in sustaining comprehension that is common to all sentences. Right posterior superior temporal cortex was recruited during sentences with long compared to short antecedent-gap linkages regardless of grammatical structure, suggesting that this brain region supports passive short-term memory during sentence comprehension. Recruitment of left inferior frontal cortex was most clearly associated with sentences that featured both an object-relative clause and a long antecedent-gap linkage, suggesting that this region supports the cognitive resources required to maintain long-distance syntactic dependencies during the comprehension of grammatically complex sentences.
Electroabsorption in HgI2

Abstract The electroabsorption spectrum of HgI 2 has been investigated as a function of temperature and electric field. We find a 4/3 power law for the dependence of the electroabsorption strength on electric field and a signal increase with temperature decrease. Our experimental results are compared with the predictions of various models. We conclude that the electroabsorption in HgI 2 is due to the presence of excitons having a low oscillator strength. Some results on PbI 2 are also presented.
PM 2.5 and ozone health impacts and disparities in New York City: sensitivity to spatial and temporal resolution

Air quality health impact assessment (HIA) synthesizes information about air pollution exposures, health effects, and population vulnerability for regulatory decision-making and public engagement. HIAs often use annual average county or regional data to estimate health outcome incidence rates that vary substantially by season and at the subcounty level. Using New York City as an example, we assessed the sensitivity of estimated citywide morbidity and mortality attributable to ambient fine particulate matter (PM2.5) and ozone to the geographic (county vs. neighborhood) and temporal (seasonal vs. annual average) resolution of health incidence data. We also used the neighborhood-level analysis to assess variation in estimated air pollution impacts by neighborhood poverty concentration. Estimated citywide health impacts attributable to PM2.5 and ozone were relatively insensitive to the geographic resolution of health incidence data. However, the neighborhood-level analysis demonstrated increasing impacts with greater neighborhood poverty levels, particularly for PM2.5-attributable asthma emergency department visits, which were 4.5 times greater in high compared to low-poverty neighborhoods. PM2.5-attributable health impacts were similar using seasonal and annual average incidence rates. Citywide ozone-attributable asthma morbidity was estimated to be 15 % lower when calculated from seasonal, compared to annual average incidence rates, as asthma morbidity rates are lower during the summer ozone season than the annual average rate. Within the ozone season, 57 % of estimated ozone-attributable emergency department for asthma in children occurred in the April–June period when average baseline incidence rates are higher than in the July–September period when ozone concentrations are higher. These analyses underscore the importance of utilizing spatially and temporally resolved data in local air quality impact assessments to characterize the overall city burden and identify areas of high vulnerability.
Characterization of bending loss in hollow flexible terahertz waveguides

Attenuation characteristics of hollow, flexible, metal and metal/dielectric coated polycarbonate waveguides were investigated using an optically pumped far infrared (FIR) laser at 215 µm. The bending loss of silver coated polycarbonate waveguides were measured as a function of various bending angles, bending radii, and bore diameters. Minimal propagation losses of 1.77, 0.96 dB/m were achieved by coupling the lowest loss TE11 mode into the silver or gold coated waveguide, and HE11 mode into the silver/polystyrene coated waveguides respectively. The maximal bending loss was found to be less than 1 dB/m for waveguides of 2 to 4.1 mm bore diameters, with a 6.4 cm bend radius, and up to 150° bending angle. The investigation shows the preservation of single laser mode in smaller bore waveguides even at greater bending angles.
Beam breakup instability experiments on long-pulse electron-beam transport through rf cavities

Experiments designed to investigate the beam breakup (BBU) instability have been performed using the long-pulse MELBA electron-beam generator (0.5 - 1.5 microsecond(s) , 0.7 - 0.8 MV, ldiode equals 1 - 15 kA, lextracted equals 0.1 - 0.5 kA). The experiment consists of 10 identical pillbox cavities each containing a small microwave loop antenna designed to detect the TM110 beam breakup mode. For our cavity design the TM110 resonant frequency occurs at approximately 2.5 GHz. The cavities are connected by small diameter tubes which attenuate the RF cavity-to-cavity crosstalk. The MELBA diode and subsequent cavity system are immersed in a solenoidal magnetic field (0.8 - 3 kG). Microwaves of 2.5 GHz (1 - 4 kW), whose pulselength exceeds the beam pulse, can be injected into the initial cavity in order to prime the BBU instability. BBU instability growth is measured through the growth of 2.5 GHz RF between the first (or second) and tenth cavities. The BBU growth is compared with predictions made by beam-cavity coupled-mode theory.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
MONTE CARLO STUDY OF THE SPIN-1/2 HEISENBERG MODEL IN 1, 2, AND 3 DIMENSIONS

The properties of the spin-1/2 Heisenberg model on 1, 2, and 3-dimensional lattices are calculated using the Decoupled Cell Method of Homma et al., and these results are compared with high temperature and spin-wave expansions, and with other numerical approaches. The DCM has advantages over other Monte Carlo methods currently in wide use in that the transition probability is positive definite, there is no need to introduce an additional imaginary time, or Trotter, dimension, and the acceptance rate for transitions is comparable to that of classical lattice models. We find very good agreement between the DCM and the high temperature expansion in the temperature region where the high temperature expansion is valid, and reasonably good agreement at low temperatures with spin wave theory. The DCM fails for temperatures T < Tc which decreases with the size of the cell.
Mother and Teen Daughter Socialization Toward Ethical Apparel Consumption

Informed by socialization theory, this study explored whether and how mothers and their teen daughters socialize one another with respect to ethical apparel consumption. The study also examined variables that may influence mothers' and teen daughters' ethical apparel consumption. An online survey provided useable data from 100 mother–daughter pairs. Paired-sample t-tests revealed that mothers and daughters differed relative to the attributes they valued in making apparel purchases (e.g., ethical, functional, social acceptance, and personal aesthetics) as well as in their levels of fashion involvement, materialism, charitable/social cause involvement, and ethical apparel consumption. Mothers and daughters perceived that the mothers were more likely to initiate conversations about ethical consumption, supporting a traditional model of socialization. Mothers' ethical apparel purchase behavior was predicted by ethical attributes of apparel and frequency of mother–daughter communication about ethical consumption. Daughters' ethical apparel purchase behavior was predicted by ethical attributes and their involvement in charitable/social causes.
Acoustic differences between content and function words in amyotrophic lateral sclerosis

Studies describing acoustic characteristics of speech produced by individuals with dysarthria may help to explain intelligibility deficits for these speakers. One goal of the current study was to i...
Warped mourning: stories of the undead in the land of the unburied

Current cultures of collective memory are rather different from those of the first half of the twentieth century when they primarily reflected national memories; representations of those pasts serv...
Pup Shoving by Adult Naked Mole-Rats

Adult naked mole-rats (Heterocephalus glaber) characteristically perform an unusual behavior toward young: they shove small pups frequently and vigorously around the nest. We studied 15 litters in five captive colonies to quantify which adults shove pups, changes in shoving frequencies as pups develop, how external disturbances affect pup-shoving frequencies, and behavior of juveniles that were not shoved as pups. In all litters and colonies the breeding female shoved pups significantly more often than any other individual. Breeding females also shoved adult colony mates, but at far lower rates than they shoved pups. Breeding males shoved pups about half as often as did breeding females. Together, the parents shoved pups ten times more often than did nonbreeders. Frequencies of pup shoving peaked when pups were 3-4 wk old, roughly coincident with weaning. When colonies were disturbed experimentally, frequencies of pup shoving increased dramatically, whereas rates at which nonbreeding adults were shoved decreased sharply. We separated four newly-weaned litters and raised half the pups apart from their colony. When these litters were reunited 4-9 wk later, the unshoved (experimental) pups were the same size as the frequently shoved (control) pups, but the unshoved pups were significantly less likely to flee from a disturbance. Shoving of small pups encourages them to flee from danger, and also may enforce weaning.
On the degree of polarization of random electromagnetic fields

Random electromagnetic fields can always be decomposed into polarized and unpolarized components. Therefore, one can, at all times, associate with any field a degree of polarization which measures the relative energy density (intensity) in the polarized component. It should not be expected, however, that this degree of polarization can provide a complete description of the electromagnetic field characteristics.
The continuing influence of Fiedler’s work on companion matrices

This is a reconstruction in article-like form of a talk given at the ``Minisymposium in Honor of Miroslav Fiedler'' at the 17th ILAS Conference, held at TU Braunschweig, Germany, on Thurs 25 Aug 2011.
Exploratory Analysis of Spatial Hierarchical Clustering in Los Angeles County, California: Relationship of Opportunity-Based Accessibility, Reported Land Values, and Resident Characteristics

The phenomenon of agglomeration has long been recognized as an important component in businesses and their location decisions. A similar phenomenon may also exist in resident location of the population in an urban area. This concept may also emerge from residential segregation and ethnic enclaves. Residential segregation may be influenced by location characteristics, social composition, and accessibility. This paper uses spatial clustering indicators that comprise resident population and its characteristics, infrastructure provision, activity opportunities by opportunity type, housing supply, and synoptic measures of travel. Time of day is introduced as a fundamental unit in classifying the spatial units. Classification of spatial units is accomplished first with a cluster technique that accounts for spatial dependence in opportunity-based accessibility indicators for different variables considered individually. Normalized scores for each variable and all spatial units are then used to derive a second set...
Response of nanoparticle structure to different types of surface environments: Wide-angle x-ray scattering and molecular dynamics simulations

The structure of nanoparticles is nonstationary and changes in response to the surface environment where the nanoparticles are situated. Nanoparticle-environment interaction determines the nature of the structure change, an important consideration for evaluating subsequent environmental impact. In this work, we used ZnS nanoparticles to interact with surface environments that contain different inorganic salts, water, and organic molecules. From analysis of the pair-distribution function (PDF) derived from wide-angle x-ray scattering experiments, we found that a stronger surface interaction results in a thicker crystalline core and a thinner distorted shell, corresponding to PDF curves having larger peaks and more peaks at longer radial distances. Plane-wave electronic calculations were used to quantify the interaction strength. An analogous atomic view of the nanoparticle-environmental interactions and structures was provided by molecular dynamics simulations. The extent of response of the nanoparticle structure to various surface environments is used as a measure of the interaction strength between them.
Patterns and Risk Factors of Change in Somatic and Mood Symptoms among Older Adults

Abstract PURPOSE: This paper was concerned with patterns of individual-level, longitudinal change in depressive symptoms and factors related to those patterns among Americans 70+ years of age. Two types of depressive symptoms were considered, somatic and mood symptoms. The paper focused on whether the patterns of change and the risk factors for these two types of symptoms differed, as we might expect among old and oldest-old adults. METHODS: The analytic sample included self-respondents of the 1993–1995 Asset and Health Dynamics among the Oldest Old (AHEAD) study who were born in 1923 or earlier. Depressive symptoms were assessed using an abbreviated Center for Epidemiologic Studies-Depression (CES-D) Scale. The analyses involved examination of respondents' change scores in depressive symptoms and multivariate models using ordinary least squares (OLS) and seemingly unrelated regressions (SUR). RESULTS: In aggregate, somatic symptoms were more common than mood symptoms initially and over time. Despite differences in aggregate rates, AHEAD respondents' individual-level patterns of change for the two types of symptoms were similar; i.e., stability was the principal trend (53–60%), followed by improvement (21–26%). A number of factors related to change in one aspect of depressive symptoms and not the other, or had greater effects on one aspect of depressive symptoms than the other; e.g., physical health had greater effects on somatic than mood symptoms. CONCLUSIONS: This study suggests that, in investigations of the course and risk factors for depressive symptoms among people 70+ years of age, it is important to separate somatic symptoms from mood symptoms; their etiology may differ. In general, factors reflecting respondents' social milieu (e.g., bereavement, residential relocation) may have greater effects on mood than somatic symptoms, whereas certain factors representing physical health may have greater effects on somatic symptoms.
Use of magnetic resonance imaging and p‐31 magnetic resonance spectroscopy to detect and quantify muscle dysfunction in the amyopathic and myopathic variants of dermatomyositis

Objective. To investigate the use of magnetic resonance imaging (MRI) and P-31 magnetic resonance spectroscopy (MRS) in characterizing the metabolic and functional status of muscles in patients with amyopathic dermatomyositis (DM) and to compare the findings with those in patients with classic myopathic DM. Methods. Nine patients with amyopathic DM, 11 patients with myopathic DM, and 11 normal individuals were studied. MRI images of thigh muscles were obtained, and T1 and T2 relaxation times were calculated. Biochemical status was quantitated with P-31 MRS, by determining concentrations of phosphate metabolites during rest and exercise. Results. Patients with amyopathic DM showed no muscle inflammation, and MRS data obtained during rest were normal. During exercise at 25% and 50% maximum voluntary contractile force, the MRS data revealed significant differences between amyopathic DM patients and control subjects indicating inefficient metabolism. In contrast, muscles of patients with myopathic DM showed inflammation and metabolic abnormalities even during rest. Conclusion. Metabolic deficiencies in patients with amyopathic DM were unmasked by exercise, suggesting that the 2 DM syndromes may share muscle abnormalities. MRI/MRS may be useful in diagnosis and optimization of treatment.
Solution of the diffusion equation in multi‐material domains by sub‐division of elements along reconstructed interfaces

This paper describes the accurate solution of the diffusion equation in three-dimensional multi-material domains where some mesh elements contain more than one material. Given the volume fractions of each material in mesh elements, the method first recreates the material interfaces in the elements using interface reconstruction methods. Then the mesh is subdivided along the interfaces making sure that the final polyhedral mesh is conforming. Finally, the diffusion equation is solved on the sub-divided mesh containing all single material elements. It is shown that the method produces second-order accurate solutions with a lower error than methods that average the material properties in the multi-material elements. Published in 2010 by John Wiley & Sons, Ltd.
SPINA BIFIDA OCCULTA IN HOMOZYGOUS PATCH MOUSE EMBRYOS

In normal embryos, mRNA en- coding platelet-derived growth factorA(PDGFA) and the platelet-derived growth factor receptor a (PDGFRa) are found within and adjacent to the site of vertebral development, the sclerotome. These patterns of expression are consistent with PDGF action on the developing sclerotome and dermis. Homozygous Patch (Ph) mutant mouse embryos lack the receptor gene (Pdgfra) due to an extensive deletion at that locus. Consistent with the spatial pattern of Pdgfra expression, striking deformities are found in the spine and ribcage of Ph/Ph embryos. In particular, we show that late-gestation Ph/Ph embryos have occult spina bifida involving the entire spinal column. We have analyzed the progression of the axial defects in homozygous Patch embryos in detail. By late gestation it appears that the components of the vertebrae are present, yet the neural arches of the spine are misshapen. We propose that PDGF A is required for proper positioning of the neural arch condensation at all axial levels. Fur- thermore, since the neural tube appears to close normally, we suggest that spina bifida in the Ph homozygote is caused primarily by a somitic mesoderm abnormality rather than a neural tube defect.Dev. Dyn. 209:105-116, 1997. r 1997 Wiley-Liss, Inc.
Kinetic Characterization of Exonuclease-Deficient Staphylococcus aureus PolC, a C-family Replicative DNA Polymerase

PolC is the C-family replicative polymerase in low G+C content Gram-positive bacteria. To date several structures of C-family polymerases have been reported, including a high resolution crystal structure of a ternary complex of PolC with DNA and incoming deoxynucleoside triphosphate (dNTP). However, kinetic information needed to understand the enzymatic mechanism of C-family polymerases is limited. For this study we have performed a detailed steady-state and pre-steady-state kinetic characterization of correct dNTP incorporation by PolC from the Gram-positive pathogen Staphylococcus aureus, using a construct lacking both the non-conserved N-terminal domain and the 3′–5′ exonuclease domain (Sau-PolC-ΔNΔExo). We find that Sau-PolC-ΔNΔExo has a very fast catalytic rate (kpol 330 s−1) but also dissociates from DNA rapidly (koff ∼150 s−1), which explains the low processivity of PolC in the absence of sliding clamp processivity factor. Although Sau-PolC-ΔNΔExo follows the overall enzymatic pathway defined for other polymerases, some significant differences exist. The most striking feature is that the nucleotidyl transfer reaction for Sau-PolC-ΔNΔExo is reversible and is in equilibrium with dNTP binding. Simulation of the reaction pathway suggests that rate of pyrophosphate release, or a conformational change required for pyrophosphate release, is much slower than rate of bond formation. The significance of these findings is discussed in the context of previous data showing that binding of the β-clamp processivity factor stimulates the intrinsic nucleotide incorporation rate of the C-family polymerases, in addition to increasing processivity.
Pathologically activated therapeutics for neuroprotection

Many drugs that have been developed to treat neurodegenerative diseases fail to gain approval for clinical use because they are not well tolerated in humans. In this article, I describe a series of strategies for the development of neuroprotective therapeutics that are both effective and well tolerated. These strategies are based on the principle that drugs should be activated by the pathological state that they are intended to inhibit. This approach has already met with success, and has led to the development of the potentially neuroprotective drug memantine, an N-methyl-D-aspartate (NMDA)-type and glutamate receptor antagonist.