cssi/SciSciGPT-SciSciNet huggingface dataset:
Future mobility-enhanced society enabled by semiconductor technology

The automotive industry is in the midst of a once-in-a-century transformation. The industry began adopting semiconductors in the 1960s, starting with rectifier diodes for alternators. Then, the spread of electronically controlled engines that supported emission control in the 1970s triggered wide-scale installation of semiconductor devices (Figure 1.3.1). The automotive semiconductor market has grown rapidly since the 1980s [1]. Further growth is expected as electrification, autonomous vehicles, and connected vehicles develop (Figure 1.3.2). In the past, when semiconductors were introduced into automobiles, the purpose was to improve performance by replacing conventional mechanical controls with electronic ones; it is important to note that no changes were made to the major components. But, for the projected disruptive transformation (already underway), dramatic changes to all major automobile components and related concepts are expected. Electrification (replacing the internal combustion engine (ICE) with an electric motor), automated driving (replacing the human driver with artificial intelligence (AI)), and connected vehicles (replacing independent automobiles with ones that are incorporated into society) will play important roles in this transformation as the automobile evolves in a major way.
Pharmacotherapy and ROP: Going Back to the Basics

Retinopathy of prematurity (ROP) is a leading cause of blindness in preterm infants around the world. Through the development of animal models and clinical trials our understanding of the pathophysiology of this disease and approach to therapy has evolved significantly since ROP was first described in the 1940s in the United States. The mainstay of treatment in ROP remains ablative laser therapy to the avascular retina but pharmacologic agents are being more and more commonly used with new targets for pharmacotherapy emerging. This paper summarizes our current understanding of the pathophysiology of ROP based on the data gleaned from animal models and discusses current approaches to pharmacotherapy.
Black/white life expectancy differences and sociodemographics: Arkansas and the U.S

Life expectancy data by race and gender for Arkansas show whites having longer average life expectancies at birth than blacks. Racial differences in life expectancy have been found to be due to higher mortality rates for blacks due to their tendency to fall into high-risk groups. Cause-specific mortality rates by race and gender for Arkansans 25 years and older were calculated for the ten leading causes of death in the state. Blacks in Arkansas had higher mortality rates than whites for each major cause of death except pulmonary diseases and suicide.
External Flats to Varieties in PG(∧ 2 (V)) Over Finite Fields

We study subspaces W of ∧2(V), V a vector space over a finite field Fq, which miss certain projective varieties. In some cases we get exact bounds on the dimension of such subspaces and improve on bounds implied by the work of Delsarte and Goethals. We also construct examples meeting the conjectured bounds. Finally, application is made to the problem of embedding the Lie Incidence geometry An-1,2(q) in small-dimensional projective spaces and to other geometric constructions.
System Overview and Key Design Considerations

This chapter describes which categories of voltage converters are covered in this book. Various applications of on-chip high-voltage generators such as memory applications for MNOS, DRAM, NAND Flash, NOR Flash, and phase-change memory, and other electronic devices for motor drivers, white LED drivers, LCD drivers, and energy harvesters are overviewed. System configuration of the on-chip high-voltage generator and key design consideration for the building circuit blocks such as charge pumps, pump regulators, oscillators, level shifters, and voltage references are surveyed.
Postural and spatial orientation driven by virtual reality

Orientation in space is a perceptual variable intimately related to postural orientation that relies on visual and vestibular signals to correctly identify our position relative to vertical. We have combined a virtual environment with motion of a posture platform to produce visual-vestibular conditions that allow us to explore how motion of the visual environment may affect perception of vertical and, consequently, affect postural stabilizing responses. In order to involve a higher level perceptual process, we needed to create a visual environment that was immersive. We did this by developing visual scenes that possess contextual information using color, texture, and 3-dimensional structures. Update latency of the visual scene was close to physiological latencies of the vestibulo-ocular reflex. Using this system we found that even when healthy young adults stand and walk on a stable support surface, they are unable to ignore wide field of view visual motion and they adapt their postural orientation to the parameters of the visual motion. Balance training within our environment elicited measurable rehabilitation outcomes. Thus we believe that virtual environments can serve as a clinical tool for evaluation and training of movement in situations that closely reflect conditions found in the physical world.
Upstream Metropolis: An Urban Biography of Omaha and Council Bluffs

Review of: "Upstream Metropolis: An Urban Biography of Omaha and Council Bluffs," by Lawrence H. Larsen; Barbara J. Cottrell; , Harl A. Dalstrom; and Kay Calame Dalstrom.
Harmonic Mitigation of an Improved High Voltage Current Source for On-Site System Calibration of High Voltage Transformer Loss Measurement Systems

This paper proposes an open-loop technique that mitigates the harmonic distortion in high load currents for onsite system calibrations of high voltage transformer loss measurement systems. The harmonic distortion induced by the current transconductance amplifier and current injector poses high burden on the feedback current correction loop and thus may compromise the measurement accuracy. Accordingly, a harmonic mitigation technique is introduced through online system identification and open-loop anti-harmonic injection. This methodology significantly reduces the THD in the load current from 0.3% to less than 0.022%.
Unity and diversity of executive functions in creativity.

Abstract Increasing evidence suggests that executive functions (EFs) – a set of general-purpose control processes that regulate thoughts and behaviors – are relevant for creativity. However, EF is not a unitary process, and it remains unclear which specific EFs are involved. The present study examined the association between the three EFs, both uniquely (EF-Specific) and together (Common EF), and three measures of creativity. Participants (N = 47) completed a divergent thinking test, and self-reported their real-life creative accomplishments. A subset of participants indicated their involvement in the artistic or information technology (IT) professions. Results indicated that fluency (but not originality) of divergent thinking was uniquely predicted by working memory Updating. Better response Inhibition predicted higher number of real-world artistic creative achievements. Involvement in the artistic (versus IT) professions was associated with better Common EF, and with enhanced mental set Shifting abilities. Results demonstrate that different EFs predict creativity depending on its operational definition.
2006 U.S. Children's Literature Award Winners

Winners of some of the leading awards for children's literature discuss the inspiration for their writing, their writing methods, and ideas for teachers who wish to use their books in the classroom.
Tiotropium in asthma: From bench to bedside.

Abstract Objective Tiotropium is a long-acting muscarinic antagonist approved for maintenance treatment of asthma in children, adolescents, and adults in the United States, and recommended as add-on treatment for uncontrolled asthma despite treatment with inhaled corticosteroids and/or long-acting beta-2 agonists. This review traces the journey of tiotropium from its historical origins through early preclinical testing to human clinical trials and real-life studies. Data sources A search was performed in PubMed using search terms ‘tiotropium’ and ‘asthma.’ Relevant references cited in those articles were reviewed. Study selections English language articles published from December 2008–December 2018 were screened. Articles evaluating the efficacy, cost-effectiveness, real-life evidence, and steroid-sparing effect of tiotropium with inadequately controlled asthma were included. Results Anticholinergics have a long history of use in the treatment of obstructive airway diseases. Evidence indicates that tiotropium's mechanism of action consists of bronchodilation and diminished mucus secretion, with preclinical evidence suggesting an anti-inflammatory effect as well. Phase 2 and 3 clinical trials have demonstrated that tiotropium is efficacious and safe, resulting in significant improvements in lung function in adults, adolescents, and children across asthma severities. Emerging evidence suggests that add-on tiotropium might potentially enable reductions in inhaled corticosteroid dose in patients with uncontrolled asthma. Further, tiotropium is a cost-effective treatment option that is also effective in the clinical practice setting. Conclusions An increasing body of evidence indicates that tiotropium can play a significant role in the treatment of patients with uncontrolled asthma.
A Feasibility Study to Measure Physical Activity, Fatigue, Sleep–Wake Disturbances, and Depression in Young Adults During Chemotherapy

Little is known about the physical activity (PA) of young adults (YAs) during cancer therapy. In this feasibility study, 14 YAs (20–34 years old) completed a six-minute walk test, recorded their steps per day for one week, and answered weekly self-reports about physical activity, fatigue, sleep–wake disturbances, and depression during one cycle of chemotherapy. Findings suggest YAs are willing to complete a PA study during chemotherapy and have variable sleep and activity schedules. Their symptoms varied in severity, with highest scores for fatigue. Studies to improve PA in YAs during chemotherapy are warranted to manage short- and long-term treatment effects.
Structural and Biochemical Consequences of Pyridoxine-Dependent Epilepsy Mutations That Target the Aldehyde Binding Site of Aldehyde Dehydrogenase ALDH7A1.

In humans, certain mutations in the gene encoding aldehyde dehydrogenase 7A1 are associated with pyridoxine-dependent epilepsy (PDE). Understanding the impact of PDE-causing mutations on the structure and activity of ALDH7A1 could allow for the prediction of symptom-severity and aid the development of patient-specific medical treatments. Herein, we investigate the biochemical and structural consequences of PDE missense mutations targeting residues in the aldehyde substrate binding site: N167S, P169S, A171V, G174V, and W175G. All but G174V could be purified for biochemical and X-ray crystallographic analysis. W175G has a relatively mild kinetic defect, exhibiting a fivefold decrease in kcat with no change in Km . P169S and N167S have moderate defects, characterized by catalytic efficiencies of 20- and 100-times lower than wild-type, respectively. A171V has a profound functional defect, with catalytic efficiency 2000-times lower than wild-type. The crystal structures of the variants are the first for any PDE-associated mutant of ALDH7A1. The structures show that missense mutations that decrease the steric bulk of the side chain tend to create a cavity in the active site. The protein responds by relaxing into the vacant space, and this structural perturbation appears to cause misalignment of the aldehyde substrate in W175G and N167S. The P169S structure is nearly identical to that of the wild-type enzyme; however, analysis of B-factors suggests the catalytic defect may result from altered protein dynamics. The A171V structure suggests that the potential for steric clash with Val171 prevents Glu121 from ion pairing with the amino group of the aldehyde substrate. ENZYMES: Aldehyde dehydrogenase 7A1 (EC1.2.1.31). DATABASES: Coordinates have been deposited in the Protein Data Bank under the following accession codes: 6O4B, 6O4C, 6O4D, 6O4E, 6O4F, 6O4G, 6O4H.
Pentachloro-1,3,6-tris(diethylphenylphosphino)dirhenium(II,III).

The title complex [systematic name: penta­chloro-1κ3Cl,2κ2Cl-tris(diethylphenylphosphino)-1κP,2κ2P-dirhenium(II,III)(Re—Re)], 1,3,6-Re2Cl5(PEt2Ph)3 or [Re2Cl5(C10H15P)3], consists of dirhenium mol­ecules with eclipsed structures similar to those of previously characterized 1,3,6-Re2Cl5(PR3)3 compounds. The Re—Re bond distance is 2.2262 (3) A and the metal–metal bond order is 3.5.
Amazon’s Machine Learning Toolkit: Sagemaker

In this chapter we will learn how to setup the machine learning service using Amazon’s offering for using the first time. The service is called as Sagemaker and it presents a fairly comprehensive set of tools to build a complete end to end pipeline to solve a machine learning problem. We will build a pipeline using Sagemaker to solve a similar problem that we solved using Azure ML and in the process will compare and contrast the pros and cons of this system with Azure ML.
Trends and Outcomes of Gray Zone Lymphoma in the United States: A Population-Based Registry Study

Introduction Gray zone lymphoma (GZL) denotes a group of unclassifiable lymphomas, having features intermediate between diffuse large B-cell lymphoma and classical Hodgkin's lymphoma. First described in 2005 and recognized in the WHO classification in 2008 as mediastinal GZL. Recently, a non-mediastinal GZL (NMGZL) was also characterized. Given its rarity and new recognition, information on its incidence and survival is scarce. Methods The SEER (Surveillance, Epidemiology, and End Results) registry was used to identify patients with histologically confirmed GZL between 2005-2016. Incidence rates (IR) were age-adjusted according to the 2000 US Standard Population. Annual percentage change (APC) and overall survival (OS) were assessed using the weighted least square and Kaplan-Meier methods, respectively. Factors with p-values Results A total of 564 cases were identified corresponding to an IR of 0.53 per million person-years. The IR of GZL increased over time, from 0.14 in 2005 to 1.27 in 2016, with an APC of 27.7% (95% confidence intervals [CI]: 23.1-32.4), p Conclusions This represents the largest population-based study for GZL. IRs increased over time, notably in the elderly; which may be explained by a better understanding of the disease and the recent characterization of NMGZL, occurring mostly in the elderly. Older age, advanced stage, and presence of SS may predict worse outcomes. Survivors of GZL may have increased future risk of thyroid tumors, possibly attributed to neck radiation.
Association between MRSA Colonization and Chronic Lung Allograft Dysfunction in Lung Transplantation for Cystic Fibrosis

Purpose Incidence of and risk factors for chronic lung allograft dysfunction (CLAD) in lung transplantation for cystic fibrosis (CF) are not established. Methicillin resistant staphylococcus aureus (MRSA) is associated with CF morbidity but its association with CLAD is unclear. We aimed to describe CLAD incidence and assess if pre-transplant MRSA colonization is associated with CLAD. Methods Retrospective cohort analysis of patients receiving a lung transplant for CF from 6/2005-3/2018 at the University of Pittsburgh Medical Center. Patients with Burkholderia species were excluded. Colonization was defined as at least one positive culture in the year before transplant. CLAD was defined by ISHLT criteria. We used competing risks methods to estimate CLAD incidence and assess associations between MRSA and CLAD. Results Of 101 patients 34% were colonized with MRSA (n=34), 87% with Pseudomonas (n=88), and 31% with Aspergillus (n=31). Median post-transplant survival was 10.8 years and did not differ by MRSA colonization (p=0.50). CLAD incidence was 25% (95% CI 16-35%) at 5 years and 37% (95% CI 27-52%) at 10 years. BOS accounted for 74% (n=20/27) of cases, RAS 22% (n=6/27), and there was 1 mixed phenotype. CLAD incidence at 5 years was 45% (95% CI 25-62%) for MRSA colonized vs 18% (95% CI 9-29%) for non-colonized patients (Figure 1). Adjusting for established CLAD risk factors and co-colonization with Pseudomonas and Aspergillus, MRSA was associated with increased incidence of CLAD (SDH 2.53, 95% CI 1.16-5.51). Among 6-month survivors, MRSA colonization was associated with increased incidence of CLAD (SDH 2.66, 95% CI 1.03-6.88) adjusting for episodes of acute cellular rejection and recurrence of pre-transplant organisms. Conclusion Incidence of CLAD in our cohort of CF recipients is low and varies by pre-transplant microbiota. MRSA colonization may be a risk factor for CLAD, perhaps reflecting differences in microbiome composition and associated host-microbiome interactions.
The Clinical Benefit of Adjuvant Therapy in Long-Term Survival of Early-Stage Ampullary Carcinoma: A Single Institutional Experience.

Background: The role of adjuvant chemotherapy (CT) or combination chemoradiation (CRT) remains uncertain for ampullary carcinoma (AC). In this analysis, we reviewed our institution’s experience with early-stage AC. Methods: AC patients who had definitive surgical intervention at the University of Alabama, Birmingham, between 2005 and 2015, were identified. Clinicopathologic factors and disease statuses were obtained from chart review. The univariate Cox proportional hazard model was conducted for evaluating the parameters associated with overall survival (OS). Kaplan-Meier method and log-rank method were used to compare the time-to-events. We estimated the survival for the patients who had definitive surgery (pancreaticoduodenectomy (PD) or ampullectomy), and followed them up with assessing the influence of adjuvant treatment (chemoradiotherapy or CT) alone on the survival in the early-stage (stage I/II) AC. Results: A total of 63 patients had definitive surgery. The median OS and progression-free survival (PFS) for all the patients who had definitive surgery were 40.5 months and 28 months, respectively. Adjuvant treatment was administered in 60% of patients with early-stage (stage I/II) AC (CT 36% and CRT 24%), while 22% were on surveillance post surgery. The pathological stage ? 2, Lymph node (LN) metastasis, peri-nodal extension (PNE) and peri-pancreatic extension (PPE) were found to be the determinants for poor OS and PFS by univariate analysis. Multiple Cox regression of these variables showed a significant influence of PPE and pathological staging on the OS and PFS, respectively. In the early-stage AC with no high-risk features, adjuvant therapy did not improve the survival over surgery alone (40.5 vs. 51.7 months, P = 0.93). The addition of radiation to CT did not yield improved outcome in early-stage cancers. For CRT and CT, OS was 22.8 versus 65.7 months (P = 0.3975), and PFS was 25.3 versus 65.7 months (P = 0.4699). Conclusions: In the early-stage AC, adjuvant therapy may not improve the outcome in the short term but may benefit over a long period. It should be considered, especially in patients with adverse risk factors. Radiation therapy may not be useful in managing AC in the adjuvant setting. J Clin Med Res. 2020;12(9):560-567 doi: https://doi.org/10.14740/jocmr4267
Listening to your patient: don't jump to amplified pain!

17 year old male presented for a second opinion of back and hip pain that started insidiously 5 months prior. Lumbar MRI done 1 month after pain began was normal. Despite 3 months of dedicated physical therapy, his pain worsened and progressed to involve his left hip. He developed an …
Which Way from Here

On March 3, 1972, the spacecraft Pioneer 10 was launched from its pad at Cape Canaveral, Florida, bound for the giant planets Jupiter and Saturn. In addition to its plethora of scientific instruments, the craft also carried a small, gold-plated plaque with a unique message engraved on it. The plaque (Fig. 29.1) showed a man and woman against the outline of the spacecraft, a sketch of the solar system with the trajectory of the spacecraft indicating where it had originated from, and the positions of fourteen prominent pulsars in our galaxy from which the location of our solar system could be determined. Also shown was a diagram of the hydrogen atom, whose frequency and wavelength of radiation could be used as a universal clock and yardstick. By comparing the wavelength to the number shown in binary code next to the woman’s image, an alien scientist could infer the size of those who sent this cosmic messenger. Similarly, by comparing the observed frequency of each pulsar with the data on the plaque, the time that has elapsed since the launch of the craft could be deduced (based on the fact that a pulsar’s frequency decreases steadily at a known rate). Thus Homo sapiens sent an identifying message across the cosmic ocean, announcing to any alien civilization our existence in this niche of our galaxy.
A Brief Overview of Biosensors

This chapter begins with defining biosensors and their basic requirements by looking at the different challenges a biosensor face in comparison with other sensors. After that, it provides a brief overview of the two major components of biosensors, namely, sensitive elements and the underlying signal transduction techniques. For the sensitive elements, the most commonly used ones including antibodies, nucleotides, enzymes, cells, and synthetic molecules are discussed and the advantages and drawbacks of each are highlighted. For the signal transduction methods, techniques based on mechanical, optical, electromagnetic, electrical, and electrochemical means are reviewed. To close the discussion, it presents an important link between surface modification and the surface properties of electrodes in biosensors.
Labor Grievance Arbitration in the United States

In the United States, the relationship between labor unions and employers is primarily governed by written collective bargaining agreements negotiated and entered into by the parties themselves. These agreements are generally for a relatively short fixed term (often three years) and are enforceable in court by either party against the other. Among the subjects typically covered in collective bargaining agreements are rates of pay, employee discipline, seniority, sub-contracting, and union security. If a subject is not covered in the agreement, employees generally have no remedy under the American system.1
Midwestern Retail Garden Centers Identify Satisfaction/Dissatisfaction with Supplying Wholesale Nurseries

Abstract A survey was conducted to assess the attitudes of Midwestern retail nursery operators concerning current marketing, promotion, sales, and service practices of their wholesale nursery stock suppliers. Completed questionnaires were received from 290 individuals (42.2% response rate). Respondents indicated quality of plant materials (96.5%), availability of plant materials in desired quantities (67.8%), wide assortment of plant materials (53.5%), and price of nursery stock (40.3%) were very important reasons for conducting business with a wholesale supplier. The majority of respondents said they were ‘very satisfied’ with the condition of bare-root trees and shrubs (75.1%), bedding plants (72.9%), herbaceous perennials and ornamental grasses (72.2%), container-grown trees and shrubs (72.0%), and balled-and-burlapped trees and shrubs (67.4%) shipped by their wholesale supplier. Over one-half (56.5%) also said they were ‘very satisfied’ with aquatic plant shipments. On those occasions when plants arri...
The Endogeniety Problem in Cost-Benefit Analysis: Valuing Policies that Alter Preferences or Genetic Identities

Cost-benefit analysis, an important technique in American public sector decision-making, is used to assess policies through aggregating the estimated willingness to pay of the affected persons to enjoy the benefits or avoid the burdens of those policies. Such analyses are generally based on the implicit simplifying assumptions that both the preferences of existing persons and the genetic identities of the persons who will comprise future generations are exogenous with respect to that policy. If, however, some persons’ preferences are endogenous in that they are altered by a policy, which is often the case, then this exogenous preferences assumption will introduce error into the analysis. It is necessary for accurate policy assessment under endogenous preferences circumstances to determine whether the policy’s consequences should be valued with regard to those persons’ pre-policy implementation preferences, or instead with regard to their post-policy implementation preferences, and/or with regard to any transitional preferences. I propose in this article a framework for conducting cost-benefit analysis under endogenous preferences circumstances that addresses this concern. The problems posed for cost-benefit analysis by the implicit assumption that the genetic identities of the members of future generations are exogenous to the policy under consideration are much more serious, and that assumption can be shown to be completely untenable. Any cost-benefit analysis that purports to include policy impacts upon future generations and that rests upon this assumption will reach results and recommendations that are irrelevant to the real choices at hand. The genetic identities of the members of future generations are always endogenous, since all policies will have exponentially proliferating and eventually universal and eternal “person-altering consequences.” These important person-altering consequences should not be overlooked when conducting cost-benefit analysis. However, attempts to incorporate those consequences into the willingness to pay-based valuation methodology lead to counterintuitive and unhelpful results. The proper resolution of this endogeniety of identity problem is unclear. It may be necessary to discard cost-benefit analysis or at least supplement it with alternative assessment methodologies that are based on non-consequentialist ethical criteria
The physics of "vacuum" breakdown

The initial plasma formation on the surface of a cathode of a vacuum diode, vacuum arc, and many other discharges is highly non-uniform. Micron-sized cathode spots form within nanoseconds. Despite the fundamental importance of cathode spots for the breakdown process, their structure, and the source of the required high energy density were not well understood. When an increasing voltage is applied, enhanced field emission of electrons begins from a growing number of small spots or whiskers. This and the impact of ions stimulate desorption of weakly bound adsorbates from the surface of a whisker. The cross section for ionization of the neutrals has a maximum for ∼ 100 eV electrons. As the diode voltage increases, the 100 V equipotential surface which moves towards the cathode is met by the desorbed neutrals moving away from the cathode. These two regions proceed from no overlap to a significant amount of overlap on a nanosecond time scale. This results in the sharp risetime for the onset of ionization. Ions produced in the ionization region, a few μm from the electron emitting spot are accelerated back. This bombardment with ∼ 100 eV ions leads to surface heating of the spot. Since the ion energy is deposited only within a few atomic layers at a time instead of an entire whisker volume, and since the neutral contaminants are only loosely bound to the surface, the onset of breakdown by this mechanism requires much less current than the joule heating mechanism. Ion surface heating is initially orders of magnitude larger than joule heating. As more ions are produced, a positive space charge layer forms which enhances the electric field and thus strongly enhances the field emitted electron current. The localized build-up of plasma above the electron emitting spot then naturally leads to pressure and electric field distributions which ignite unipolar arcs. The high current density of the unipolar arc and the associated surface heating by ions provide the "explosive" formation of a cathode spot plasma.
What Can Improve Chronic Disease Care

Chronic disease care is a central part of geriatrics. The rise in chronic disease draws attention to the need to find better ways to deliver effective care. This essay examines the effectiveness of several strategies for providing better chronic disease care, reviewing the literature and relying on extant reviews whenever possible. The evidence of effectiveness is mixed; a few areas show promise. The case for cost-effectiveness is even less strong. New strategies may be indicated, including more-proactive monitoring of clinical courses and assessing patients' readiness to participate actively in their own care.
Hepatic adenoma. A case report.

A case of hepatic cell adenoma showed on ultrasound, radioisotope scanning and angiography is shown. The importance of the angiography on accurate diagnosis and precise location prompts the report of this proven case.
International Tourism, Demand, and GDP Implications: A Background and Empirical Analysis

International tourism, a primary source of growth for many countries, is inadequately represented in the economic literature. This paper attempts to expand upon past research, thereby supplementing some deficiencies and posing new questions. A pooled model for international tourism demand is constructed for 85 countries using fixed-effects specification. In addition to conventional variables, a variable representing political conditions acts as a proxy for the many exogenous impacts that affect tourism. The nature of tourism volatility due to the exogenous shocks is discussed, and a statistical link between concentrations in tourism as an export good and GDP volatility is explored. This article is available in Undergraduate Economic Review: http://digitalcommons.iwu.edu/uer/vol1/iss1/2 Undergraduate Economic Review A publication of Illinois Wesleyan University
Nonlinear effects on the carrier-envelope phase

Calculations, using Maxwells equations, of nonlinear effects on the carrier-envelope phase of ultrashort pulses propagating in sapphire show that the slope with respect to intensity changes signs due to the finite response time of n/sub 2/.
Site-specific mutagenesis and DNA recombination by using PCR to generate recombinant circles or by recombination of linear PCR products

This article describes two methods in which the polymerase chain reaction (PCR) is used for site-specific mutagenesis and for DNA recombination without any enzymatic reaction in vitro apart from DNA amplification. The first method generates DNA joints in vitro by using separate PCR amplifications to generate products that when combined, denatured, and reannealed form double-stranded DNA with single-stranded ends. These single-stranded ends are designed to anneal to each other to yield circles, an application termed recombinant circle PCR (RCPCR). RCPCR-generated DNA circles form without restriction enzyme digestion or ligation and can be transfected directly into Escherichia coli. The second method generates DNA joints in vivo by using the polymerase chain reaction to add homologous ends to DNA. Following transfection of the linear PCR product(s) into strains of E. coli used routinely in cloning, recombination of these homologous ends in vivo permits cloning of the mutant or recombinant of interest. The second method, termed recombination PCR (RPCR), diminishes the number of primers necessary to generate a given mutant or recombinant to half that necessary in RCPCR, because it eliminates the need to generate staggered ends in vitro.
Electrical property of cardiac cell membrane of spontaneously hypertensive rat.

Abstract The ventricular action potential of the spontaneously hypertensive rat is significantly longer than that of the normotensive rat, but there is no difference in other electrical properties of these cardiac cells aside from that attributed to age. Catecholamines, ACh and KCl produce similar effects on the membrane properties of hypertensive and normotensive rats. Potassium excess (4 mM KCl) causes cardiac arrest in the spontaneously beating heart of hypertensive rat but not that of normotensive rat nor that of hypertensive rat when electrically driven.
Primary adenocarcinoma of the esophagus arising in a columnar-lined esophagus.

A patient presenting with dysphagia and weight loss was found to have a large midesophageal mass. Five biopsies indicated only adenoma but a brush cytology specimen under direct vision was diagnostic of adenocarcinoma. Esophagotomy and resection of tumor with follow-up radiotherapy were performed; histologic examination confirmed the diagnosis. To date, there has been no recurrence of the tumor. This patient was subsequently found to have a columnar-lined esophagus. Since columnar-lined esophagus may predispose to malignancy, this case illustrates the diagnostic importance of direct-vision cytology in patients with columnar-lined esophagus.
Harmonic wave propagation in an infinite viscoelastic medium with a periodic array of cylindrical elastic fibers

Abstract The work involves the propagation of plane harmonic waves in an infinite isotropic medium in which a doubly periodic array of cylindrical fibers is embedded. The direction of propagation is perpendicular to the fibers and the matrix material is taken to be viscoelastic in shear, modeled through hereditary integrals. A finite element method based on Galerkin's technique is employed, which leads to a non-linear eigenvalue problem. An iterative scheme is used to obtain two modes of dispersion, for both real and imaginary wave numbers, for a specific composite.
Interruption of cell-cell communication in Chinese hamster V79 cells by various alkyl glycol ethers: implications for teratogenicity.

Intercellular communication most likely plays a significant coordinating role in morphogenesis. Blockage of a specific type of intercellular communication, that mediated by gap junctions, has been proposed as a mechanism of action of some teratogens. Several glycol ethers have recently been shown to be teratogenic in laboratory animals. Because these compounds are negative in genotoxic assays, it is suggested that they may act by nongenetic, perhaps membrane-mediated mechanisms. In the present study several structurally related alkyl glycol ethers were examined for their ability to block junction-mediated intercellular communication. Interruption of intercellular communication was measured in vitro by an assay that depends on the transfer of metabolites via gap junctions, i.e., metabolic cooperation. All compounds tested--ethylene glycol (EG), ethylene glycol monomethyl ether (EGME), ethylene glycol monoethyl ether (EGEE), ethylene glycol monopropyl ether (EGPE), and ethylene glycol monobutyl ether (EGBE)--were able to block metabolic cooperation in vitro. The potencies of the compounds were inversely related to the length of the aliphatic chain, the dose required for maximum blockage increasing as the aliphatic chain shortened. Some differences in the maximum amount of blockage were detected, but these were not consistent and hence were not considered significant. Cytotoxicity, as measured by cell survival, was also related to the structure of the compound, generally increasing with increased length of the aliphatic chain. There were structurally related differences in the concentration ranges over which the compounds were effective.(ABSTRACT TRUNCATED AT 250 WORDS)
Navigating the Library: What Students (and Faculty) Need To Know.

Abstract A key factor in ensuring students' academic success is to make certain that they do not feel lost or intimidated when undertaking library research assignments. Classroom faculty and librarians working in collaboration can help ease students' research anxiety by providing them with some simple pre-research tools. Included in this article are “Library Tips for Students,” and for faculty “Guidelines for Designing and Implementing Effective Library Research Assignments,” “Characteristics of Effective Assignments,” and “Pitfalls to Avoid” when designing these assignments. Students, classroom faculty, and librarians benefit when students receive a solid foundation for their research undertakings.
Electrical stiffness tuning in ferromagnetic shape memory Ni-Mn-Ga

This paper is focused on the dynamic characterization of field-induced mechanical stiffness changes under varied bias magnetic fields in commercial-quality, single-crystal ferromagnetic shape memory Ni-Mn-Ga. Prior to the dynamic measurements, a specified variant configuration is created in a prismatic Ni-Mn-Ga sample through the application and subsequent removal of collinear or transverse bias magnetic fields. Base excitation is used to measure the acceleration transmissibility across the sample, from where the resonance frequency is directly identified. These measurements are repeated for various collinear and transverse bias magnetic fields ranging from 0 to 575 kA/m, which are applied by a solenoid and an electromagnet, respectively. A 1-DOF model for the Ni-Mn-Ga sample is used to calculate the mechanical stiffness from resonance frequency measurements. A resonance frequency increase of 21% and a stiffness increase of 52% are observed in the collinear field tests. In the transverse field tests, a resonance frequency decrease of -36% is observed along with a stiffness decrease of -61%. The damping exhibited by this material is low in all cases (≈ 0.03). The measured dynamic behaviors make Ni-Mn-Ga well suited for vibration absorbers with electrically-tunable stiffness.
Two journeys to seventeenth-century Palestine

This article describes two seventeenth-century accounts of voyages to Palestine-one by an Arab, the Moroccan jurist Salim Abdallah al-Ayyashi, in 1663; and the other by an Englishman, one "T B.," in 1669. The two texts, though sharing a focus on holy sites inspired by their scriptures, reveal not only sharply differing views of Palestine but also widely divergent worldviews and approaches to history and the meaning of travel.
Variability and infant development.

This special issue extends the systematic study of variability to development in infancy. The articles document both between-subject and within-subject variability and establish their relations to important behavioral outcomes in a wide variety of domains. In addition, the research describes useful methods for studying variability during infancy and illustrates the types of theoretical insights that can be realized by studying change as it occurs.
How accurate is the visual assessment of basal carcinoma margins

SUMMARY This study evaluated the accuracy of visual determination of tumour margins in basal cell carcinomas. Using a 2.5 × binocular magnifier, the apparent tumour margin was marked pre-operatively by light electrodesiccation. Following excision, the electrodesiccation mark was compared to the actual tumour edge by microscopy of step level sections. It was possible to delineate the tumour margins with an accuracy of 1 mm in 94% of a selected series of 101 basal cell carcinomas. These findings support the view that a 2 mm margin of normal tissue is adequate in the surgical treatment of most basal cell carcinomas.
Site-directed mutagenesis and spectroscopic studies of the iron-binding site of (S)-2-hydroxypropylphosphonic acid epoxidase

Abstract (S)-2-Hydroxylpropanylphosphonic acid epoxidase (HppE) is a novel type of mononuclear non-heme iron-dependent enzyme that catalyzes the O2 coupled, oxidative epoxide ring closure of HPP to form fosfomycin, which is a clinically useful antibiotic. Sequence alignment of the only two known HppE sequences led to the speculation that the conserved residues His138, Glu142, and His180 are the metal binding ligands of the Streptomyces wedmorensis enzyme. Substitution of these residues with alanine resulted in significant reduction of metal binding affinity, as indicated by EPR analysis of the enzyme–Fe(II)-substrate-nitrosyl complex and the spectral properties of the Cu(II)-reconstituted mutant proteins. The catalytic activities for both epoxidation and self-hydroxylation were also either eliminated or diminished in proportion to the iron content in these mutants. The complete loss of enzymatic activity for the E142A and H180A mutants in vivo and in vitro is consistent with the postulated roles of the altered residues in metal binding. The H138A mutant is also inactive in vivo, but in vitro it retains 27% of the active site iron and nearly 20% of the wild-type activity. Thus, it cannot be unequivocally stated whether H138 is an iron ligand or simply facilitates iron binding due to proximity. The results reported herein provide initial evidence implicating an unusual histidine/carboxylate iron ligation in HppE. By analogy with other well-characterized enzymes from the 2-His-1-carboxylate family, this type of iron core is consistent with a mechanism in which both oxygen and HPP bind to the iron as a first step in the in the conversion of HPP to fosfomycin.
Imaging ability and effective use of guided imagery

Imaging ability, the ability to generate mental images and become absorbed in them as if they were real, is proposed as a moderator in the relationship between guided imagery and symptom relief. Two existing measures of image generation, Marks's (1973) Vividness of Visual Imagery Questionnaire and Betts's (1909) shortened Questionnaire Upon Mental Imagery (Sheehan, 1967), and one measure of absorption, Tellegen's Absorption scale (1993; TAS) were completed by 60 graduate students prior to listening to a guided imagery intervention to relieve anxiety associated with an upcoming stressful task. Analyses were conducted using data from 30 participants (7 men and 23 women) who reported an increase in anxiety level after learning of the stressful task. Participants were divided into two groups, successful (n = 21) and unsuccessful (n = 9) users of imagery, based on change in anxiety scores after listening to the guided imagery intervention. Absorption (TAS) scores were significantly higher for persons in the successful group; there were no differences in image generation scores. Two TAS items were identified as potential predictors of success with guided imagery. Findings may be helpful in developing a clinically useful instrument to predict likelihood of success with guided imagery in relieving cancer pain and its distress. © 1998 John Wiley & Sons, Inc. Res Nurs Health 21:189–198, 1998
3×3 coupler-based homodyne optical coherence microscopy

We present a homodyne optical coherence microscope (OCM) for high-resolution en face imaging. The OCM exploits the inherent phase shifts of 3×3 fiber-optic couplers to simultaneously obtain complete quadrature amplitude and phase information of samples.
Tunable microlens arrays actuated by various thermo-responsive hydrogel structures

We report on liquid-based tunable-focus microlens arrays made of a flexible polydimethylsiloxane (PDMS) polymer. Each microlens in the array is formed through an immiscible liquid–liquid interfacial meniscus. Here deionized water and silicone oil were used. The liquids were constrained in the PDMS structures fabricated through liquid-phase photopolymerization for molding and soft lithography. The microlenses were actuated by thermo-responsive N-isopropylacrylamide (NIPAAm) hydrogel microstructures and could be tuned individually by changing the local temperature. The NIPAAm hydrogels expanded and contracted, absorbing and releasing water, at different temperatures. Thus the pressure across the water–oil interface in the microlenses varied responding to the temperature, tuning their corresponding focal lengths. The microlens diameter was 2.4 mm. The typical microlens focal length was measured to be from 8 to 60 mm depending on the temperature. The microlens response time actuated by different structures and components of the NIPAAm hydrogels were compared. The normalized light intensities of the microlens focused spots were measured, matching well with a Zemax simulation, to study the microlens spherical aberrations. The NIPAAm hydrogel durability was also measured.
Isoproterenol as a potential pulmonary vasodilator in primary pulmonary hypertension

Abstract The effects of various pharmacologic agents on pulmonary arterial pressure and vascular resistance were studied in six patients considered to have primary pulmonary hypertension at the time of cardiac catheterization. Vascular resistance increased slightly after the administration of hypoxic air in two patients; it decreased after the administration of 100 percent oxygen in one patient. After the intravenous administration of diphenhydramine and sodium salicylate, drugs that block the actions of the powerful pulmonary vasoconstrictors histamine and prostaglandin (F α 2 ), vascular resistance did not change in two patients. After the intravenous administration of hydrocortisone, vascular resistance decreased significantly in one patient but only slightly in four others. Vascular resistance did not change significantly after the administration of the immunosuppressive agents prednisone and azathioprine in three patients. These results suggest that neither hypoxia, histamine nor prostaglandin plays a role in the etiology of primary pulmonary hypertension. The possible role of an immune mechanism needs further investigation. Vascular resistance decreased after the acute intravenous administration of the potent pulmonary vasodilator isoproterenol (0.5 to 2 μg/min) in five of the six patients. Both pulmonary pressure and resistance decreased in two patients and there was no change in pressure in one patient after the “subacute” administration of isoproterenol (0.5 to 1 μg/min) for 5 to 12 days. In all patients both values returned to control level when isoproterenol was discontinued. The sublingual administration of isoproterenol (15 mg) significantly decreased vascular resistance in one patient but not in the other three patients studied. The one patient who responded has been receiving maintenance doses of isoproterenol for 30 months. We conclude that isoproterenol is not uniformly effective in all patients, but that it is a useful therapeutic agent in patients who respond.
A ROLE FOR NAUTILUS IN THE DIFFERENTIATION OF MUSCLE PRECURSORS

In the Drosophila embryo, nautilus is expressed in a subset of muscle precursors and differentiated fibers and is capable of inducing muscle-specific transcription, as well as myogenic transformation. In this study, we examine the consequences of nautilus loss-of-function on the development of the somatic musculature. Genetic and molecular characterization of two overlapping deficiencies, Df(3R)nau-9 and Df(3R)nau-11a4, revealed that both of these deficiencies remove the nautilus gene without affecting a common lethal complementation group. Individuals transheterozygous for these deficiencies survive to adulthood, indicating that nautilus is not an essential gene. These embryos are, however, missing a subset of muscle fibers, providing evidence that (1) some muscle loss can be tolerated throughout larval development and (2) nautilus does play a role in muscle development. Examination of muscle precursors in these embryos revealed that nautilus is not required for the formation of muscle precursors, but rather plays a role in their differentiation into mature muscle fibers. Thus, we suggest that nautilus functions in a subset of muscle precursors to implement their specific differentiation programs.