cssi/SciSciGPT-SciSciNet huggingface dataset:
Parameter Estimation in Layered Media Using Dispersion-Constrained Inversion

AbstractThe need to estimate the properties of layered elastic or viscoelastic media arises commonly in various engineering applications, including geotechnical site characterization and pavement c...
Comparison of US County-Level Public Health Performance Rankings With County Cluster and National Rankings: Assessment Based on Prevalence Rates of Smoking and Obesity and Motor Vehicle Crash Death Rates.

Importance Health departments can be grouped together based on sociodemographic characteristics of the population served. Comparisons within these groups can then help with monitoring and improving the health of their populations. Objective To compare county-level percentile rankings on outcomes of smoking, motor vehicle crash deaths, and obesity within sociodemographic peer clusters vs nationwide rankings. Design, Setting, and Participants This cross-sectional, population-based study of demographic and health data from the 2014 Behavioral Risk Factor Surveillance System and the 2016 Robert Wood Johnson Foundation County Health Rankings data set was conducted at 3139 of 3143 US counties and county-equivalents. Four locations were excluded due to incomplete data. Data analysis was conducted between January and August 2017. Exposures Random forest algorithms were used to identify sociodemographic characteristics most associated with the outcomes of interest. These characteristics were race and ethnicity, educational attainment, age, marital status, employment status, sex, and health insurance status.k-means clustering was used to cluster counties based on these sociodemographic characteristics and the percentage of the county classified as rural. Main Outcomes and Measures County-level smoking prevalence, motor vehicle crash death rate, and obesity prevalence. County percentile rankings on the outcomes of interest were compared in the national context and the within-cluster context. Results A total of 318 856 967 individuals (mean [SD] individuals per county, 101 579.2 [326 315]; 161 911 910 women [50.8%]) were represented by the 3139 counties used in this analysis. Eight distinct sociodemographic clusters throughout the United States were found. Cluster-specific percentile rankings for both smoking prevalence and motor vehicle crash death rates improved more than 70 percentile points for several counties in the rural, American Indian cluster compared with the nationwide percentiles. Conversely, the young, urban, middle to high socioeconomic status cluster included counties with cluster-specific percentile rankings that declined by 60 percentile points or more compared with the nationwide rankings for all 3 outcomes of interest. Conclusions and Relevance Comparing county health outcomes on a nationwide or statewide basis fails to adequately account for sociodemographic context. Clustering counties by sociodemographic factors related to the outcome of interest allows a better understanding of other factors that may be shaping the prevalence of health outcomes. These groupings may also aid learning exchange.
Ablative radiation therapy for locally advanced pancreatic cancer: techniques and results

Standard doses of conventionally fractionated radiation have had minimal to no impact on the survival duration of patients with locally advanced unresectable pancreatic cancer (LAPC). The use of low-dose stereotactic body radiation (SBRT) in 3- to 5-fractionshas thus far produced a modest improvement in median survival with minimal toxicity and shorter duration of treatment, but failed to produce a meaningful difference at 2 years and beyond. A much higher biologically effective dose (BED) is likely needed to achieve tumor ablation The challenge is the delivery of ablative doses near the very sensitive gastrointestinal tract. Advanced organ motion management, image guidance, and adaptive planning techniques enable delivery of ablative doses of radiation (> = 100Gy BED) when more protracted hypofractionated regimens or advanced image guidance and adaptive planning are used. This approach has resulted in encouraging improvements in survival in several studies. This review will summarize the evolution of the radiation technique over time from conventional to ablative and describe the practical aspects of delivering ablative doses near the GI tract using cone beam CT image (CBCT) guidance and online adaptive MRI guidance.
Everything Old Is New Again: Reviving the Traditional Choreographic Pedagogy of Louis Horst and Doris Humphrey

ABSTRACTTeaching and learning choreography have been essential parts of dance major curricula in higher education for more than eighty years. Much of its current pedagogy resourcefully stresses the...
An Essential N-Terminal Serine-Rich Motif in the AAV VP1 and VP2 Subunits That May Play a Role in Viral Transcription

Adeno-associated virus (AAV) is one of the most researched, clinically utilized gene therapy vectors. Though clinical success has been achieved, transgene delivery and expression may be hindered by cellular and tissue barriers. Understanding the role of receptor binding, entry, endosomal escape, cytoplasmic and nuclear trafficking, capsid uncoating, and viral transcription in therapeutic efficacy is paramount. Previous studies have shown that N-terminal regions of the AAV capsid proteins are responsible for endosomal escape and nuclear trafficking, however the mechanisms remain unknown. We identified a highly-conserved three-residue serine/threonine (S/T) motif in the capsid N-terminus, previously uncharacterized in its role in intracellular trafficking and transduction. Using alanine scanning mutagenesis, we found S155 and the flanking residues, D154 and G158, are essential for AAV2 transduction efficiency. Remarkably, specific capsid mutants show a 5 to 9-fold decrease in viral mRNA transcripts, highlighting a potential role of the S/T motif in transcription of the viral genome.
Characteristics and outcomes of lung cancer in solid organ transplant recipients.

Abstract Objectives Lung cancer is the third most common malignancy that develops in patients following solid organ transplantation and is the leading cause of cancer deaths in the general population. The aims of this study are to examine the characteristics of patients who developed lung cancer following solid organ transplantation at our institution and to compare their outcomes to those of lung cancer patients without a history of transplant. Materials and methods We performed a single-institution retrospective study of 44 solid organ transplant recipients who developed lung cancer and compared their characteristics to a cohort of 74 lung cancer patients without a history of transplant. We performed propensity score weighted analyses to compare outcomes between the two groups, including a cox proportional hazards model of overall survival. Results 52 % of post-transplant patients who developed lung cancer were diagnosed with stage III or IV disease. In the propensity score weighted analysis that accounted for age at diagnosis, sex, lung cancer stage at diagnosis, Charlson comorbidity index score, and ECOG performance score, post-transplant patients were more likely to have squamous cell histology (p Conclusions When compared to non-transplant patients with lung cancer, post-transplant patients have worse overall survival after accounting for differences in age, sex, lung cancer stage, comorbidities, and performance status. This survival difference is not solely attributable to differences in tumor histology and treatments received. This may suggest that post-transplant malignancies are more aggressive and difficult to treat.
Finding a Fit: Biological Science Doctoral Students’ Selection of a Principal Investigator and Research Laboratory

In the laboratory-based disciplines, selection of a principal investigator (PI) and research laboratory (lab) indelibly shapes doctoral students' experiences and educational outcomes. Framed by the theoretical concept of person-environment fit from within a socialization model, we use an inductive, qualitative approach to explore how a sample of 42 early-stage doctoral students enrolled in biological sciences programs made decisions about fitting with a PI and within a lab. Results illuminated a complex array of factors that students considered in selecting a PI, including PI relationship, mentoring style, and professional stability. Further, with regard to students' lab selection, peers and research projects played an important role. Students actively conceptualized trade-offs among various dimensions of fit. Our findings also revealed cases in which students did not secure a position in their first (or second) choice labs and had to consider their potential fit with suboptimal placements (in terms of their initial assessments). Thus, these students weighted different factors of fit against the reality of needing to secure financial support to continue in their doctoral programs. We conclude by presenting and framing implications for students, PIs, and doctoral programs, and recommend providing transparency and candor around the PI and lab selection processes.
Intravenous Sodium Ferric Gluconate Complex And Iron Dextran Are Safe For Administration During Hospitalization For Heart Failure With Reduced Ejection Fraction

Introduction Iron deficiency (ID) with or without anemia is common in patients who have heart failure with reduced ejection fraction (HFrEF). Several trials have demonstrated improvement in symptoms and exercise tolerance in response to IV iron in patients with chronic HFrEF. To date, no large randomized trials evaluating the impact of IV iron on mortality and hospitalization in acutely decompensated HFrEF patients have been published. In addition, the interchangeability of IV iron preparations in this population is unknown. Currently, our institution has only sodium ferric gluconate complex (SFGC) and iron dextran on inpatient formulary. Hypothesis Administration of IV SFGC or iron dextran during hospitalization for acute decompensated HFrEF reduces mortality and cardiovascular (CV) hospitalization with a low rate of adverse events. Methods Single-center, retrospective cohort study of adult patients with a primary discharge diagnosis of heart failure, a reduced EF ( Results Of the 141 patients included in the efficacy analysis, 33 were in the intervention group and 108 were in the control group. Groups were generally well-matched. Hemoglobin, ferritin, and iron saturation were significantly lower in the intervention group at baseline. The primary outcome occurred in 45.5% of intervention group patients and 62% of controls (p=0.091). Among the safety population (N=82), 45 patients received IV SFGC, 37 iron dextran, and one both agents. One AE (nausea) was reported. Conclusion Administration of IV SFGC or iron dextran was associated with a non-significant reduction in 90-day CV hospitalization or mortality. The low incidence of reported AEs supports safety of these IV iron formulations in the study population. Results from large randomized trials regarding morbidity and mortality are eagerly anticipated.
Change in psychological distress in response to changes in reduced mobility during the early 2020 COVID-19 pandemic: Evidence of modest effects from the U.S.

Abstract Rationale During the early 2020 COVID-19 pandemic, several US states had implemented stay-in-place orders (SIPOs) with varying degrees of stringency which resulted in inter-state differences in mobility (i.e., longer presence at home). We test whether the inter-state differences in mobility influenced changes in reported psychological distress. Our study is not on the surge in COVID-19 in the later part of 2020. Objective To identify whether the change in state-level mobility is associated with the change in individuals’ reported psychological distress during the early COVID-19 pandemic and whether the intensity of the association varies by older individuals, females, and nonwhites. Methods We use differences in state-level mobility and change in reported psychological distress between the two dates of interviews of 5,132 individuals who participated in March and April 2020 waves of Understanding America Study (UAS). Results We find support for modest effects, i.e., a one standard deviation decline in mobility was associated with a 3.02% higher psychological distress [95% CI: 0.4%–5.64%], and the effects are robust to controlling for reported changes in exercise intensity, alcohol consumption, cannabis use, recreational drug use, and meditation intensity. We also find support for a stronger association for females, but not for older individuals or non-whites. Further, we do not find support for the mediation effects from change in chance of running out of money or change in chance of getting COVID-19. Conclusion Our findings show that reduced mobility from lockdowns during the early COVID-19 wave in the US is associated with a modest increase in reported psychological distress, especially for females. However, these conclusions should not be construed as a small increase in psychological distress in general, as a variety of non-mobility related factors associated with COVID-19 could have exacerbated psychological distress during the early COVID-19 wave in the US.
Use of Diagnostic Testing and Intervention for Sensorineural Hearing Loss in US Children From 2008 to 2018

Importance Early detection and intervention of pediatric hearing loss is critical for language development and academic achievement. However, variations in the diagnostic workup and management of pediatric sensorineural hearing loss (SNHL) exist. Objective To identify patient and clinician factors that are associated with variation in practice on a national level. Design, setting, and participants This cross-sectional study used the Optum claims database to identify 53 711 unique children with SNHL between January 1, 2008, and December 31, 2018. Main outcomes and measures National use rates and mean costs for diagnostic modalities (electrocardiogram, cytomegalovirus testing, magnetic resonance imaging, computed tomography, and genetic testing) and interventions (speech-language pathology, billed hearing aid services, and cochlear implant surgery) were reported. The associations of age, sex, SNHL laterality, clinician type, race/ethnicity, and household income with diagnostic workup and intervention use were measured in multivariable analyses. Results Of 53 711 patients, 23 735 (44.2%) were girls, 2934 (5.5%) were Asian, 3797 (7.1%) were Black, 5626 (10.5%) were Hispanic, 33 441 (62.3%) were White, and the mean (SD) age was 7.3 (5.3) years. Of all patients, 32 200 (60.0%) were seen by general otolaryngologists, while 7573 (14.10%) were seen by pediatric otolaryngologists. Diagnostic workup was received by 14 647 patients (27.3%), while 13 482 (25.1%) received intervention. Use of genetic testing increased (odds ratio, 1.22 per year; 95% CI, 1.20-1.24), whereas use of computed tomography decreased (odds ratio, 0.93 per year; 95% CI, 0.92-0.94) during the study period. After adjusting for relevant covariables, children who were seen by pediatric otolaryngologists and geneticists had the highest odds of receiving workup and intervention. Additionally, racial/ethnic and economic disparities were observed in the use of most modalities of diagnostic workup and intervention for pediatric SNHL. Conclusions and relevance This cross-sectional study identified factors associated with disparities in the diagnostic workup and intervention of pediatric SNHL, thus highlighting the need for increased education and standardization in the management of this common sensory disorder.
Head and Neck Pathology

Intraoperative consultation (IOC) is routinely performed for the evaluation of head and neck lesions. Specimens are received from a variety of locations including the oral cavity, pharynx, larynx, salivary glands, and lymph nodes. The spectrum of neoplastic and nonneoplastic lesions in this location is broad and can pose diagnostic difficulty on IOC. This chapter will highlight the most common intraoperative challenges that are encountered.
Understanding the roles of physical therapists on the care team: An interprofessional education experience for first-year medical students

Abstract Physical therapy (PT) and occupational therapy (OT) are essential to recovery from illness and injury, as well as maintaining and improving quality of life. As the utilization of PT and OT increases, a physician's understanding of these interprofessional colleagues' practice is critical. This study aimed to improve first-year medical students' self-rated understanding of PT and OT, and intentions to incorporate these health professions into future care plans. First-year medical students participated in a 2-h interprofessional (IP) clinical observation experience in outpatient PT. Before the experience students received a handout reviewing the respective clinical focuses of PT and OT, potential reasons for referral, trajectory of care, and an example case. During the experience, students shadowed patient sessions and discussed the principles of PT and OT and key clinical details of the patient they were observing with a provider preceptor. Experience effectiveness was evaluated via post-experience 5-point Likert scale surveys and qualitative prompts given to students and providers. The PT Clinical Observation Experience resulted in a significant increase in students' self-rated confidence in their understanding of PTs'/OTs’ roles, knowledge of when to refer a patient, and intent to incorporate PT/OT into future care plans. All providers agreed the experience helped students improve their communication skills with other interprofessional team members. This curriculum experience achieved learning objectives with no additional monetary costs or training of facilitators, making it a feasible and useful mechanism for medical schools without associated professional schools to provide IP experiences to preclinical students. Additionally, this experience addresses gaps in medical student education regarding the roles and responsibilities of PT and OT and helps build a foundation for future interprofessional collaboration. Handouts and surveys used in this study are included in this report.
Strain and sex dependent effects of isolation housing relative to environmental enrichment on operant sensation seeking in mice.

Sensation seeking is a multidimensional phenotype that predicts the development of drug addiction in humans and addiction-like drug seeking in rodents. Several lines of evidence suggest that chronic stress increases sensation seeking and addiction-like drug seeking through common genetic mechanisms. Discovery and characterization of these mechanisms would reveal how chronic stress interacts with the genome to influence sensation seeking and how drugs of abuse hijack these fundamental reward mechanisms to drive addiction. To this end, we tested the hypothesis that chronic isolation housing stress (relative to environmental enrichment) influences operant sensation seeking as a function of strain, sex, or their interaction. To determine if the BXD recombinant inbred panel could be used to identify genetic and epigenetic mechanisms underlying any identified gene-by-environment interactions, we used mice from the two BXD founder strains. Following 10 weeks of differential housing, we assessed operant sensation seeking using several reinforcement schedules. The primary finding from this study was that DBA/2J but not C57BL/6J mice were significantly vulnerable to an isolation-induced increase (relative to environmental enrichment) in sensation seeking during extinction when the sensory reward was no longer available; this effect was significantly more robust in females. These data reveal a previously unknown isolation-induced effect on extinction of operant sensation seeking that is sex-dependent, addiction-relevant, and that can be dissected using the BXD recombinant inbred panel.
Extension of the Bessmertnyĭ Realization Theorem for Rational Functions of Several Complex Variables

We prove a realization theorem for rational functions of several complex variables which extends the main theorem of Bessmertnyĭ (in: Alpay, Gohberg, Vinnikov (eds) Interpolation Theory, Systems Theory and Related Topics. Operator Theory Advances and Applications vol 134. Birkhauser Verlag, Basel, pp 157–185, 2002). In contrast to Bessmertnyĭ’s approach of solving large systems of linear equations, we use an operator theoretical approach based on the theory of Schur complements. This leads to a simpler and more “natural” construction to solving the realization problem as we need only apply elementary algebraic operations to Schur complements such as sums, products, inverses, and compositions. A novelty of our approach is the use of Kronecker product as opposed to the matrix product in the realization problem. As such our synthetic approach leads to a solution of the realization problem that has potential for further extensions and applications within multidimensional systems theory especially for those linear models associated with electric circuits, networks, and composites.
1 – The Treatment of Uncertainty in the Physical Sciences

This chapter discusses the uncertainty in the physical sciences with the observation that complete certainty about anything in the world is an unattainable goal. Modern science is preoccupied with themes such as chaos, quantum indeterminacy, fuzzy logic, and semantic analysis. The current paradigms tend to embrace uncertainties rather than the alleged certainties of the past. Certainty comes in two major varieties: primitive certainty and derivative certainty. Primitive certainty derives directly from the human senses. It is the kind of certainty experienced when one perceives objects or events in the immediate environment. Derivative certainty pertains to knowledge that is deduced or inferred from observations or occurrences that may not have been perceived. Uncertainty was formally admitted into science over 300 years ago when studies began to be made on the outcomes of games of chance. Since that time, probability arguments have remained with us and have been employed in the description and characterization of myriad scientific systems. Around the turn of the century, several totally unexpected developments in the physical sciences occurred—the founding of the quantum mechanics, the discovery that even deterministic systems could exhibit chaotic behavior, and the realization that traditional Aristotelian logic had its limitations when applied to real-world systems. Starting with the quantum-theoretical concepts, fuzzy reasoning quickly manifested its suitability for the description of physicochemical concepts.
Computer-aided Research and Teaching of Roman Law: A Database of Justinianean Sources

1. The Research Project 2. The Database 3. The Documentary Unit 4. Searching the Database 5. Retrieval by Sources 6. Bibliographical-Linguistic Retrieval.
Collective modes and the superconducting-state spectral function of Bi2Sr2CaCu2O8

Photoemission spectra of the high-temperature superconductor Bi2Sr2CaCu2O8 near (pi,0) show a dramatic change when cooling below T-c: the broad peak. in the normal state turns into a sharp low-energy peak followed by a higher binding-energy hump. Recent experiments fmd that this row-energy peak persists over a significant range in momentum space. We show in this paper that these data are well described by a simple model of electrons interacting with a collective mode that appears only below T-c.
Sequences downstream of AAUAAA signals affect pre-mRNA cleavage and polyadenylation in vitro both directly and indirectly.

Abstract To investigate the role of sequences lying downstream of the conserved AAUAAA hexanucleotide in pre-mRNA cleavage and polyadenylation, deletions or substitutions were constructed in polyadenylation signals from simian virus 40 and adenovirus, and their effects were assayed in both crude and fractionated HeLa cell nuclear extracts. As expected, these sequences influenced the efficiency of both cleavage and polyadenylation as well as the accuracy of the cleavage reaction. Sequences near or upstream of the actual site of poly(A) addition appeared to specify a unique cleavage site, since their deletion resulted, in some cases, in heterogeneous cleavage. Furthermore, the sequences that allowed the simian virus 40 late pre-RNA to be cleaved preferentially by partially purified cleavage activity were also those at the cleavage site itself. Interestingly, sequences downstream of the cleavage site interacted with factors not directly involved in catalyzing cleavage and polyadenylation, since the effects of deletions were substantially diminished when partially purified components were used in assays. In addition, these sequences contained elements that could affect 3'-end formation both positively and negatively.
Teaching Through Testimonio: Accessing Community Cultural Wealth in School

Using the concept of community cultural wealth, this article examines the ways that a group of 3rd-grade students engaged in writing testimonios, or personal narratives, to reflect on their cultural and linguistic lives in and outside of the classroom. Countering deficit notions of Latina/o students, families, and communities, this study illuminates the powerful ways that students utilize various forms of community cultural wealth. The findings indicate that testimonio can be an effective pedagogical tool to help students identify their individual and collective community cultural wealth and draw on these forms of knowledge in the elementary classroom.
Multimedia tool set for teaching ergonomic analysis skills

Ergonomics remains an important issue in industry today. Preventing and solving harmful ergonomic situations in the workplace can lead to greater productivity, profit, and employee moral. Currently, the School of Continuing Education at the Georgia Institute of Technology presents a week long course in ergonomics for industry personnel. This course covers basic ergonomic topics, including anthropometric charts, data on human limitations, and the principles of workplace design, and how to conduct a survey of the workplace for harmful ergonomic activities. An important aspect of this course is learning to apply the basic ergonomic data while conducting a survey, that is, using the knowledge of human abilities and limitations to identify harmful ergonomic activities that are present while a worker is doing his or her job. We have proposed, built, and evaluated a prototype multimedia instructional system, called ErgoTrainer. ErgoTrainer aids students, both students taking classes like the one taught at Georgia Tech and students learning on their own, in gaining basic ergonomic knowledge and learning the skill of job surveillance. The evaluation was successful and the results were positive.
Java Card and OCF

In this chapter, we present a sample Java Card applet together with the basic concepts of on-card programming for Java Cards. We explain the associated off-card programming and show how OCF brings off-card and on-card parts together. You can find a brief introduction to the Java Card platform in Section 2.3.2 “Java Card”.
Beyond Cell Doctrine

Cell doctrine is the foundational paradigm of Euro-American medicine and biology. Even without stepping outside that tradition, one may imagine alternate models of the body such as a fluid model in which cells do not exist or a model wherein cells are described as overlapping fields of molecular organization in space and time. With a complexity analysis of cell biology, we find that the existence of cells as unitary entities, as things, is contingent on the level of scale at which the body is observed. Therefore, alternate models of the body may be conceived that are specific and appropriate to other levels of scale. These ideas suggest that some bodily phenomena, particularly from Asian traditions, which have previously resisted explanation from within the cell-based Euro-American tradition (e.g., acupuncture) may be productively investigated with one or more of these other models. Additionally, the seemingly metaphorical concepts from Tibetan medicine of the coarse, energy, and subtle bodies may represent precise, though somewhat poetically expressed representations of the body at different levels of scale.
Robotic therapy for chronic stroke: general recovery of impairment or improved task-specific skill?

There is a great need to develop new approaches for rehabilitation of the upper limb after stroke. Robotic therapy is a promising form of neurorehabilitation that can be delivered in higher doses t...
Variation in Oil Content Among Mexican and Peruvian hirsuta Peanut Landraces and Virginia-Type hypogaea Lines1

Abstract Many consumers in the U.S. claim to prefer low fat foods, and this has encouraged the search for peanut (Arachis hypogaea L.) cultivars with low or reduced oil content. A collector's note on the low oil content of PI 576616, a Peruvian-type peanut (A. hypogaea subsp. hypogaea var. hirsuta Kohler) prompted screening of similar landraces from Mexico. PI 576633, PI 576634, PI 576635, PI 576636, PI 576637, and PI 576638 were collected in 1993 and imported to the U.S. for evaluation. In 1994, 120plants per landrace were planted in the field, using Peruvian hirsuta PI 501296 as a control. In 1995, 24 selections from each Mexican landrace, 10 selections from PI 501296, and North Carolina State Univ. (NCSU) breeding line N91026E were planted. Based on oil analysis of the lines tested in 1995, 23 low oil and eight high oil selections were planted with four NCSU virginia-type breeding lines (N91026E, N92038, N94006L, and N94014L) used as controls in 1993. Nuclear magnetic resonance (NMR) was used for oil c...
An American in Berlin: reflections on the German demographic challenge, immigration, and national identity

The “German Demographic Challenge”—an aging society, low birth rates, a falling population size, and a shrinking working-age population—also affects less tangible facets of Germany’s future because these issues may have implications for how Germans see themselves and how they define themselves as a nation-state. This paper explores the complex relationships between national identity, migration, and other population processes in the German context. One consequence of the demographic challenge, acting in concert with immigration, is that the German population will become more diverse over time. Perhaps the more difficult challenge will be how Germany comes to terms with itself given the population changes it will experience.
Reactions of iron carbonyl complexes with dimethylthiocarbamoyl chloride

Abstract The reactions of dimethylthiocarbamoyl chloride with a number of neutral and ionic iron carbonyl complexes in tetrahydrofuran are described. A variety of unusual products were obtained, viz. Fe(CO)2(S2CNMe2)2 from Fe(CO)5; Fe(CO)2(S2CNMe2)(CSNMe2) from Fe2)CO)9, Fe3(CO)12, and Fe(CO)42−; [Fe-(CO)2(S2CNMe2)(CNMe2)(CNMe2)2S]+ from Fe(CO)42−, and Fe4(CO)12S(CSNMe2)-(CNMe2) from Fe2(CO)82−, as well as Fe2(CO)6(CSSEt)2 from Fe2(CO)9 and ClCSSEt. The structures and behavior and some reactions of these complexes are described.
Relation of cognitive reserve and task performance to expression of regional covariance networks in an event-related fMRI study of nonverbal memory

Cognitive reserve (CR) has been established as a mechanism that can explain individual differences in the clinical manifestation of neural changes associated with aging or neurodegenerative diseases. CR may represent individual differences in how tasks are processed (i.e., differences in the component processes), or in the underlying neural circuitry (of the component processes). CR may be a function of innate differences or differential life experiences. To investigate to what extent CR can account for individual differences in brain activation and task performance, we used fMRI to image healthy young individuals while performing a nonverbal memory task. We used IQ estimates as a proxy for CR. During both study and test phase of the task, we identified regional covariance patterns whose change in subject expression across two task conditions correlated with performance and CR. Common brain regions in both activation patterns were suggestive of a brain network previously found to underlie overt and covert shifts of spatial attention. After partialing out the influence of task performance variables, this network still showed an association with the CR, i.e., there were reserve-related physiological differences that presumably would persist were there no subject differences in task performance. This suggests that this network may represent a neural correlate of CR.
Dissociative ionization of SF6 by electron impact

Abstract Dissociative ionization of SF6 by electron impact has been studied using a crossed-beam time-of-flight method. Kinetic energy and angular distributions have been obtained for F+/SF6 within the electron-energy region 45 ⩽ Et ⩽ 300 eV. Appearance potentials for the ions SF5+, SF4+, SF3+, SF2+, and F+ observed at 90° to the electron and SF6 beams are in agreement with the measurements of Dibeler and Mohler [1], and Delwiche [2].
VOLATILE ORGANIC COMPOUNDS FROM CITRUS FEED MILL EMISSIONS

Although citrus processors recover most of the essential oils in the peel, the amount remaining is released as air pollutants and volatile organic compounds (VOCs) during cattle feed manufacturing. Citrus processing plants are required to obtain permits allowing emission of 91 t/year (100 tons/year) of VOCs, an amount exceeded by most processors. The objective of this study was to develop an accurate, on-site method to measure VOC emissions, accomplished by use of adsorbent traps subsequently analyzed by gas chromatography. Over 90 percent of the oil entering the feed mill was accounted for, with d-limonene as the major VOC, including other terpenes, β-pinene and myrcene. Of sampling locations in a typical feed mill, error analysis determined the least precision (16.9%) was associated with determining the input rates of peel to the dryer. The sampling technique developed is a viable method for monitoring VOCs with reproducible results.
Epidermolytic Hyperkeratosis: Ultrastructure and Biochemistry of Skin and Amniotic Fluid Cells from Two Affected Fetuses and a Newborn Infant

Skin biopsy samples and amniotic fluid cells obtained in utero from two fetuses at risk for epidermolytic hyperkeratosis were examined by light and electron microscopy. Both fetuses were affected; the second was carried to term. Epidermal extracts were prepared from blisters of the newborn for analysis of keratin and filaggrin proteins. Abnormal clumps of keratin filaments were present in all layers of the prekeratinized fetal epidermis except the periderm and stratum germinativum. A significant population of amniotic fluid cells also contained the filament aggregations. Prenatal diagnosis of the disease should be possible using cells obtained at amniocentesis, thus avoiding fetal skin biopsy. Biochemical studies showed abnormalities in keratin and filaggrin proteins. The structural alterations in the tissue might be a consequence of altered interaction between these two abnormal epidermal proteins.
The Role of Competitor Pricing in Multiairport Choice

This paper investigates how competitors' low-fare offerings in multiairport regions influence the online search behavior of customers at a major carrier's website. Clickstream data from a major U.S. airline are combined with detailed information about competitors' low-fare offerings for 10 directional markets. The use of a truncated negative binomial model allows the prediction of the number of searches on the carrier's website as a function of low-fare offerings for the same airport pair as well as for competing airport pairs in the region. The study finds that the number of searches decreases as the difference between the carrier's lowest fare and competitors' lowest fare increases. However, trip characteristics have more impact on search behavior than do the fare variables. Overall search on the carrier's website is limited, with less than 5% of customers searching for fares across multiple airports. The findings provide insight into the role of competitor pricing on multiairport choice as it relates t...
Autorotation Test Abnormalities of the Horizontal and Vertical Vestibulo-Ocular Reflexes in Panic Disorder

Patients with panic disorder often describe dizziness as a disturbing symptom, with more severe episodes reported than in other psychiatric populations. Nineteen patients diagnosed as having a panic disorder were tested for vestibulo-ocular (VOR) abnormalities with the Vestibular Autorotation Test (VAT), a computerized test of the high-frequency (2 to 6 Hz) VOR. The patients were unselected for the presence or absence of balance disorders. Results showed VOR abnormalities, relative to a normal population, in the horizontal and/or vertical VORs of all 19 patients. Vestibulo-ocular reflex asymmetries were commonly present. Because the VAT tested the VOR over a frequency range encountered during common daily activities, the observed abnormalities could result in a perceptually moving visual field (oscillopsia). We hypothesize that the resulting experience of a visual-vestibular disturbance--perhaps in a biologically or psychologically predisposed individual--is catastrophically misinterpreted, leading to more bodily symptoms and anxiety. These could then contribute to more misinterpretation in a positive feedback sense, ultimately leading to a panic attack.
BEHAVIOR AND FORM IN THE EVOLUTION OF CAVE COLLEMBOLA

The study of evolution has always presented an exciting challenge and a series of very serious problems. Caves furnish an environment in which most of these problems can be avoided. First, the arthropod fauna of the caves is such that a living record often remains of virtually every stage in any evolutionary process which has occurred. Jeannel almost 50 years ago first noted this and said that caves were filled with living fossils. Second, caves furnish us with what is a natural evolutionary laboratory in which the evolutionary pressures are at the same time more simple and more compelling than those that we see in most surface areas. Thus caves furnish an ideal region for the study of the processes of evolution. For the past six years I have spent some time examining the evolution of one group of cave arthropods, the Collembola. Although the Collembola form an important part of the soil fauna they are poorly known among non-specialists. Fig. 1 gives an idea of the overall structure of the group concerned in this study. These animals are generally quite small. None of the forms I shall discuss here exceeds five mm. in length. The unique furcula at the end of the abdomen can be used for jumping, if the animals are hard pressed. Collembola are widely varied in both form and habitat, and are found from Antarctica to Nova Zemlya. They are common in caves and often occur in large numbers. In an earlier work (Christiansen, 1961), I showed how the distinctions between cave-dependent and cave-independent characteristics made it easy to map the phylogenies of the various groups with considerable confidence. One of the conclusions of this study was that there is an immense amount of convergence in the evolution of cave-dependent characteristics of cave Collembola. The conclusions drawn from the phylogenetic studies were amply reinforced by the data of zoogeography and relative dominance of the different forms. I also pointed out varying levels of preadaption in new cave invaders and the probable relationship between the modification of the foot complex and the increasing adaptation for locomotion over wet surfaces and standing water. Some questions were left unanswered by this work. First, what is the exact nature of behavioral evolution? Second, what is the relationship between these behavioral adaptions and the morphological changes? It is entirely possible that the cave species which are more primitive in morphological terms had compensated for this by extensive behavioral evolution. The present paper is an attempt to further clarify these problems in the subfamily Entomobryinae, where the changes involved are most extensive.
Albumin Synthesis by Rat Hepatocytes Cultured on Collagen Gels Is Sustained Specifically by Heparin

Abstract We investigated the influence of various kinds of glycosaminoglycans (GAGs) in collagen gels on the maintenance of albumin synthesis in primary culture of rat hepatocytes. Among the GAGs examined (heparin, heparan sulfate, keratan sulfate, chondroitin sulfate A, dermatan sulfate, and hyaluronic acid), only heparin-containing collagen gel cultures could significantly sustain albumin synthesis. However, other GAGs, such as heparan sulfate and keratan sulfate, had almost no effect on the maintenance of albumin synthesis. Heparin in collagen gels exhibited a dose-dependent effect on albumin synthesis: heparin at 400 μg/ml-collagen solution maintained albumin synthesis for over 3 weeks. On the other hand, when an equivalent amount of heparin was added directly to the collagen gel culture medium, it prolonged albumin synthesis for only 10 days. The results demonstrate that specific regulation of albumin synthesis by heparin was significantly promoted by coincubating it with collagen, suggesting that some specific interaction between heparin and collagen might be of importance for the maintenance of hepatocyte functions.
The role of phenotypic switching in the basic biology and pathogenesis of Candida albicans.

The ‘‘white-opaque’’ transition in Candida albicans was discovered in 1987. For the next fifteen years, a significant body of knowledge accumulated that included differences between the cell types in gene expression, cellular architecture and virulence in cutaneous and systemic mouse models. However, it was not until 2002 that we began to understand the role of switching in the life history of this pathogen, the role of the mating type locus and the molecular pathways that regulated it. Then in 2006, both the master switch locus WORI and the pheromone-induced white cell biofilm were discovered. Since that year, a number of new observations on the regulation and biology of switching have been made that have significantly increased the perceived complexity of this fascinating phenotypic transition. Keywords: white-opaque transition; sexual biofilm; WORI; interacting regulatory network; mating type locus (Published: 15 January 2014) Citation: Journal of Oral Microbiology 2014, 6 : 22993 - http://dx.doi.org/10.3402/jom.v6.22993
Long-term effect of sodium hyaluronate (Hyalgan) on osteoarthritis progression in a rabbit model.

Abstract Background : Intra-articular (IA) hyaluronan (HA) injections are approved for the treatment of knee osteoarthritis (OA) pain. One of the currently available products is approved for repeat treatment courses. While HA is classed as a symptom-modifying agent, there is substantial evidence that this therapeutic modality also possesses disease-modifying activity. Objective : A rabbit model of OA, anterior cruciate ligament transection (ACLT), was used to investigate the long-term effects of single and sequential courses of HA therapy on OA progression. Design : One or two courses of five weekly IA injections of sodium hyaluronate (Hyalgan ® ) average molecular weight, MW, of 500–730kDa, or vehicle were administered to rabbits ( N =10 per group), initiated 4 and 13 weeks (for groups that received a second course) after ACLT. Gross morphological and histomorphometric evaluations were performed on harvested knee joints following sacrifice at 26 weeks after surgery. Results : All the rabbits exhibited the characteristic pathologic changes of OA. Rabbits that received one or two courses of HA injections showed less disease progression than rabbits treated with ACLT alone or with 10 vehicle injections. However, rabbits that received five vehicle injections also showed improved morphology compared with those given no injections. Rabbits that received 10 HA injections showed significantly less surface roughness of the femoral cartilage compared with rabbits treated with ACLT, 5 HA injections, or 10 vehicle injections, and showed significantly less surface roughness of the tibial plateau compared with all other treatment groups ( P Conclusions : Repeat courses of HA injections reduced the degree of articular degeneration in a rabbit ACLT model of OA. Sequential courses of HA therapy may be advantageous in the long-term management of OA.
Comments on: Book Review by Peter Myers on Michael J. Sailor: Porous Silicon in Practice. Preparation, Characterization and Applications

The reviewer brings up some important points in his review of the book. The author regrets any confusion the statement from the preface ‘‘This book is written for the beginner— someone who has no prior training in the field’’ may have caused. It should be stressed that this book is intended for the beginner to the field of porous silicon, not a beginner to the field of science or research in general. The user of this book should have a solid undergraduate-level understanding of chemistry, and be well-acquainted with the hazards and safety procedures used in a modern chemistry or materials research laboratory. As the reviewer points out, HF is a hazardous chemical, and the reader should pay close attention to Sect. 2.4 (pg 48), which outlines the precautions in dealing with and disposing of HF and refers the reader to Appendix A2, titled ‘‘Safety Precautions when Working with Hydrofluoric Acid,’’ (pg 235). Appendix A2 is devoted to the safe handling of HF, including the MSDS, the health effects of HF exposure to various tissues of the body, and the need for ‘‘GOGGLES AND SHIELD; LAB COAT AND APRON; VENT HOOD; PROPER GLOVES.’’ That section also includes first aid for inhalation, ingestion, skin contact, and eye contact, and it includes directions to the physician in case an accidental exposure occurs. The fact that the reviewer appears to have missed these sections in the book suggests that others may also do so; it provides a good opportunity to stress the need for attention to the proper handling of HF and the other chemicals described in the book. In particular, setting up the reactor for the microwave-assisted hydrosilylation reaction described on pg 205 should be done in consultation with a safety specialist. The author wishes to re-emphasize that it is not appropriate to use a commercial microwave oven for such reactions—‘‘the use of a microwave reactor designed for chemical reactions, and that has adequate explosion safety protection is recommended.’’ The book provides schematics for etching and gas dosing cells in a series of appendices. The reviewer recommends that the user seek advice from a qualified engineer on the design, construction, and testing of the gas dosing cell be obtained. Indeed, as every user will have different goals, input from a qualified engineer should be sought for all of the schematics given in the book to ensure that the devices will serve their intended purpose safely and effectively. In the case of the gas dosing cell, it should be stressed that the cell described in Appendix A3 is an open, vented cell meant to be operated at atmospheric pressure. The author thanks the reviewer for his constructive comments and for emphasizing the need for adequate safety precautions when performing the experiments described in this book.