cssi/SciSciGPT-SciSciNet huggingface dataset:
Action-effect contingency modulates the readiness potential

The ability to constantly anticipate events in the world is critical to human survival. It has been suggested that predictive processing originates from the motor system and that incoming sensory inputs can be altered to facilitate sensorimotor integration. In the current study, we investigated the role of the readiness potentials, i.e. the premotor brain activity registered within the fronto-parietal areas, in sensorimotor integration. We recorded EEG data during three conditions: a motor condition in which a simple action was required, a visual condition in which a visual stimulus was presented on the screen, and a visuomotor condition wherein the visual stimulus appeared in response to a button press. We measured evoked potentials before the motor action and/or after the appearance of the visual stimulus. Anticipating a visual feedback in response to a voluntary action modulated the amplitude of the readiness potentials. We also found an enhancement in the amplitude of the visual N1 and a reduction in the amplitude of the visual P2 when the visual stimulus was induced by the action rather than externally generated. Our results suggest that premotor brain activity might reflect predictive processes in sensory-motor binding and that the readiness potentials may possibly represent a neural marker of these predictive mechanisms.
Synergistic interactions between confinement and macromolecular crowding spatially order transcription and translation in cell-free expression

Synergistic interactions between macromolecular crowding and confinement spatially organize transcription and translation in cells. Yet, reproducing such spatial ordering in cell-free expression platforms has proven to be elusive. Here we report crowding- and confinement-driven spatial self-organization of cell-free expression that mimics expression behavior within and around the nucleoid of prokaryotes. These experiments use Ficoll-70 to approximate cellular macromolecular crowding conditions within cell-size lipid vesicles. Intriguingly, there was an abrupt change in transcriptional dynamics when crowding reached physiologically relevant levels. Imaging experiments revealed that this change in transcriptional dynamics was coincident with localization of plasmid DNA and mRNA at the vesicle wall. Computer simulations demonstrated that crowding leads to an entropically induced attraction between plasmid DNA and the wall, causing localization of DNA near the wall at sufficiently high crowding levels. The experiments demonstrate cell-like spatial organization of translation, where translational activity is controlled by chromosomally-templated positioning of mRNA. This cell-free system provides a flexible experimental platform to probe the underlying mechanisms of self-organization of membrane-less structures in cells and the spatial control of gene expression.
Synthesis, characterization, and photophysical properties of bismetalated platinum complexes with benzothiophene ligands

Abstract Benzothiophene-based ligands containing quinoline or pyridine moieties were synthesized through Suzuki Coupling reactions and subsequently reacted with the binuclear Platinum compound, [Pt2Me4 (μ-SMe2)2], PtA, in order to study chelate-assisted C H activation. The preparation and characterization of CˆN cyclometalated products, including η2 intermediates, monometalated, and bismetalated species, are reported. The photophysical properties of the complexes were studied and compared to TD-DFT computational results.
Pediatric Cancer Outcomes in an Intensive Care Unit in Pakistan

PURPOSEAlthough cancer is uncommon, it is a significant cause of pediatric morbidity and mortality in the developing world. The need for intensive care in pediatric oncology has increased with more...
P128-M SYBR Premix Ex Taq (Perfect Real Time): An Investigation of Instrument Compatibility

In the early 1990s the discovery that Ethidium bromide (EtBr) could be used to monitor PCR cycles through binding double stranded DNA (dsDNA), resulting in a fluorescence increase, ushered in a new age in PCR. By the end of the decade new detection methods using probes (i.e. TaqMan) and instrumentation supported the launch of quantitative real time PCR (qPCR) technology. Since then many instruments and detection chemistries (FRET Hybrids, Molecular Beacons, SYBR Green and others) have been developed. Among these chemistries, the intercalating chemical SYBR Green is the most similar to EtBr and widely used. It is a fluorophore that binds dsDNA in the minor groove in a non-sequence-dependent manor. Upon binding, its fluorescence increases to ~10 times that of EtBr. This detection method is simple, sensitive and relatively inexpensive to other methods currently available. Since SYBR Green detects all dsDNA, primer dimers form during PCR will also be detected and quantified. These primer dimers and non-specific amplification can be minimized by using a “hot start” polymerase which prevents reaction initiation. To help alleviate detection of primer-dimers and other non specific amplification Takara has created SYBR Premix Ex Taq (Perfect Real Time). A convenient premix consisting of Takara’s high sensitivity-high performance Ex Taq Hot Start DNA Polymerase and SYBR Green I. Here we investigate this SYBR Green/ Ex Taq Hot Start combination and its compatibility with several qPCR instruments.
The Meta-Analysis Review: A Valuable Resource for Special Educators:

The Individuals with Disabilities Education Act (2004) and the Every Student Succeeds Act (2015) both require that educators utilize instructional practices based on evidence in the literature when...
Roles Youth Play in the Bullying Dynamic and Theoretical Explanations for Why Bullying Happens

This chapter provides an overview of roles inherent in the bullying dynamic and how these roles are related to peer social groups. Youth can be involved in the bullying dynamic as a bully, victim, bully-victim, or bystander. Sociometric status provides a window to view child and adolescent peer relationships and hierarchical group formation. A detailed discussion of sociometric status and its relationship to bullying is provided. An in-depth discussion of theoretical explanations for why bullying happens is provided, applying several theories from evolutionary psychology and sociology. Implications for practitioners are also provided.
Mitochondrial dysfunction in human primary alveolar type II cells in emphysema

Abstract Background Cigarette smoke is the main risk factor of pulmonary emphysema development, which is characterized by alveolar wall destruction. Mitochondria are important for alveolar type II (ATII) cell metabolism due to ATP generation. Methods We isolated ATII cells from control non-smoker and smoker organ donors, and after lung transplant of patients with emphysema to determine mitochondrial function, dynamics and mitochondrial (mt) DNA damage. Findings We found high mitochondrial superoxide generation and mtDNA damage in ATII cells in emphysema. This correlated with decreased mtDNA amount. We also detected high TOP1-cc and low TDP1 levels in mitochondria in ATII cells in emphysema. This contributed to the decreased resolution of TOP1-cc leading to accumulation of mtDNA damage and mitochondrial dysfunction. Moreover, we used lung tissue obtained from areas with mild and severe emphysema from the same patients. We found a correlation between the impaired fusion and fission as indicated by low MFN1, OPA1, FIS1, and p-DRP1 levels and this disease severity. We detected lower TDP1 expression in severe compared to mild emphysema. Interpretation We found high DNA damage and impairment of DNA damage repair in mitochondria in ATII cells isolated from emphysema patients, which contribute to abnormal mitochondrial dynamics. Our findings provide molecular mechanisms of mitochondrial dysfunction in this disease. Fund This work was supported by National Institutes of Health (NIH) grant R01 HL118171 (B.K.) and the Catalyst Award from the American Lung Association (K.B.).
Using WebGIS to Develop a Spatial Bibliography for Organizing, Mapping, and Disseminating Research Information: A Case Study of Quaking Aspen

On the Ground • Spatial data is valuable to researchers for locating studies that occur in a particular area of interest, or one with similar attributes. • Without a standard in publishing protocol, spatial data largely goes unreported, or is difficult to find without searching the publication. • Assigning location data and displaying points on a public web map makes locating publications based on spatial location possible.
Schematic Theories, Subsumtion of Laws, and Non-accidental Generalizations

There is a raft of issues that have to be taken into account when the background theory for a law is schematic.
Effects of MS disease-modifying therapies on responses to vaccinations: A review.

Abstract Background : Development of long-term immunologic memory relies upon humoral and cellular immune responses. Vaccinations aim to stimulate these responses against pathogens. Several studies have evaluated the impact of multiple sclerosis disease-modifying therapies on immune response to vaccines. Findings from these studies have important implications for people with multiple sclerosis who require vaccination and are using disease-modifying therapies. Methods : Searches using PubMed and other engines were conducted in May 2020 to collect studies evaluating the impact of various disease-modifying therapies on immune responses to vaccination. Results : Several studies demonstrated preserved immune responses in people treated with beta-interferons to multiple vaccine types. Limited data suggest vaccine responses to be preserved with dimethyl fumarate treatment, as well. Vaccine responses were reduced to varying degrees in those treated with glatiramer acetate, teriflunomide, sphingosine-1-phosphate receptor modulators, and natalizumab. The timing of vaccination played an important role in those treated with alemtuzumab. Humoral vaccine responses were significantly impaired by B cell depleting anti-CD20 monoclonal antibody therapies, particularly to a neoantigen. Data are lacking on vaccine responses in patients with multiple sclerosis taking cladribine and high-dose corticosteroids. Notably, the majority of these studies have focused on humoral responses, with few examining cellular immune responses to vaccination. Conclusions : Prior investigations into the effects of individual disease-modifying therapies on immune responses to existing vaccines can serve as a guide to expected responses to a SARS-CoV-2 vaccine. Responses to any vaccination depend on the vaccine type, the type of response (recall versus response to a novel antigen), and the impact of the individual disease-modifying therapy on humoral and cellular immunity in response to that vaccine type. When considering a given therapy, clinicians should weigh its efficacy against MS for the individual patient versus potential impact on responses to vaccinations that may be needed in the future.
Tangible Privacy: Towards User-Centric Sensor Designs for Bystander Privacy

Sensor-enabled computers in the form of 'IoT' devices such as home security cameras and voice assistants are increasingly becoming pervasive in our environment. With the embedded cameras and microphones in these devices, this 'invasion' of our everyday spaces can pose significant threats to the privacy of bystanders. Because of their complex functionality, even when people attempt privacy measures (such as asking the owner to "turn the camera off"), these devices may still record information because of the lack of a 'real' off button. With the ambiguities of current designs, a bystander's perceived privacy can diverge from their actual privacy. Indeed, being able to assess one's actual privacy is a key aspect in managing one's privacy according to Altman's theory of boundary regulation, and current designs fall short in assuring people of their privacy. To understand how people as bystanders manage their privacy with IoT devices, we conducted an interview study about people's perceptions of and behaviors around current IoT devices. We find that although participants' behaviors line up with Altman's theory of boundary regulation, in the face of uncertainty about their privacy, they desire or engage in various 'tangible' workarounds. Based on our findings, we identify and introduce the concept of 'tangible privacy' as being essential to boundary regulation with IoT devices. We argue that IoT devices should be designed in a way that clearly and unambiguously conveys sensor states to people around them and make actionable design recommendations to provide strong privacy assurances to bystanders.
Probing natural variation of IRE1 expression and endoplasmic reticulum stress responses in Arabidopsis accessions

The environmental effects shape genetic changes in the individuals within plant populations, which in turn contribute to the enhanced genetic diversity of the population as a whole. Thus, individuals within the same species can acquire and accumulate genetic differences in their genomes depending on their local environment and evolutionary history. IRE1 is a universal endoplasmic reticulum (ER) stress sensor that activates an evolutionarily conserved signalling cascade in response to biotic and abiotic stresses. Here, we selected nine different Arabidopsis accessions along with the reference ecotype Columbia-0, based on their geographical origins and differential endogenous IRE1 expression under steady-state conditions to investigate the natural variation of ER stress responses. We cloned and analysed selected upstream regulatory regions of IRE1a and IRE1b, which revealed differential levels of their inducibility. We also subjected these accessions to an array of biotic and abiotic stresses including heat, ER stress-inducing chemical tunicamycin, phytohormone salicylic acid, and pathogen infection. We measured IRE1-mediated splicing of its evolutionarily conserved downstream client as well as transcript accumulation of ER-resident chaperones and co-chaperones. Collectively, our results illustrate the expression polymorphism of a major plant stress receptor and its relationship with molecular and physiological ER stress sensitivity.
Is Arthroscopic Disk Repositioning Equally Efficacious to Open Disk Repositioning? A Systematic Review

Purpose Temporomandibular joint disc repositioning surgery is 1 of the treatment modalities used for treating anterior disc displacement of the temporomandibular joint. The procedure can be arthroscopic disc repositioning or open disc repositioning. This systematic review measured and compared the efficacy of arthroscopic and open disc repositioning procedures. Materials and Methods The authors conducted a systematic review without meta-analysis by performing a literature search electronically and manually covering arthroscopic and open disc repositioning studies published up to July 2020 in Pubmed, Embase, and Cochrane databases. Surgical outcomes such as changes in maximal incisal opening (MIO) and pain scores, temporomandibular joint noises, diet consistency, malocclusion, and postoperative complications were extracted and analyzed. Results A total of 28 studies were included in the review and split into those assessing open disc repositioning (n = 13) and those assessing arthroscopic disc repositioning (n = 15). The average age of the study patients in the included studies was 31.5 ± 6.8 years, and women represented 83.3% of the study population. Both arthroscopic and open disc repositioning showed to be efficacious in reducing pain and increasing MIO. Due to heterogeneity in study designs and data reporting between the studies, no quantitative analysis was performed, and the groups were not directly compared. Conclusions Both arthroscopic and open disc repositioning led to significant improvements in clinical outcomes based on pain scores and MIO. This study highlights the need for comparative studies of the 2 techniques with well-documented case selection including standardized diagnosis based on Wilkes stages and rigorous outcomes assessment including patient reported outcomes.
Indexable signal amplification for multiparametric imaging

Abstract Multiparametric imaging allows researchers to measure the expression of many biomarkers simultaneously, allowing detailed characterization of cell microenvironments. One such technique, CODEX, allows fluorescence imaging of >30 proteins in a single tissue section. In the commercial CODEX system, primary antibodies are conjugated to DNA barcodes. This modification can result in antibody dysfunction, and development of a custom antibody panel can be very costly and time consuming as trial and error of modified antibodies proceeds. To address these challenges, we developed novel tyramide-conjugated DNA barcodes that can be used with primary antibodies via peroxidase-conjugated secondary antibodies. This approach results in signal amplification and imaging without the need to conjugate primary antibodies. When combined with commercially available barcode-conjugated primary antibodies, we can very quickly develop working antibody panels. We also present methods to perform antibody staining using a commercially available automated tissue stainer and in situ hybridization imaging on a CODEX platform.
A mixed-methods study of multi-level factors influencing mammography overuse among an older ethnically diverse screening population: implications for de-implementation.

Background There is growing concern that routine mammography screening is overused among older women. Successful and equitable de-implementation of mammography will require a multi-level understanding of the factors contributing to mammography overuse. Methods This explanatory, sequential, mixed-methods study collected survey data (n= 52, 73.1% Hispanic, 73.1% Spanish-speaking) from women ≥70 years of age at the time of screening mammography, followed by semi-structured interviews with a subset of older women completing the survey (n=19, 63.2% Hispanic, 63.2% Spanish-speaking) and providers (n=5, 4 primary care, 1 obstetrics and gynecology) to better understand multi-level factors influencing mammography overuse and inform potential de-implementation strategies. We conducted a descriptive analysis of survey data and content analysis of qualitative interview data. Survey and interview data were examined separately, compared, integrated, and organized according to Norton and Chambers Continuum of Factors Influencing De-Implementation Process. Results Survey findings show that 87.2% of older women believe it is important to plan for an annual mammogram, 80.8% received a provider recommendation, and 78.9% received a reminder in the last 12 months to schedule a mammogram. Per interviews with older women, the majority were unaware of or did not perceive to have experienced overuse and intended to continue mammography screening. Findings from interviews with older women and providers suggest that there are multiple opportunities for older women to obtain a mammogram. Per provider interviews, almost all reported that reducing overuse was not viewed as a priority by the system or other providers. Providers also discussed that variation in mammography screening practices across providers, fear of malpractice, and monetary incentives may contribute to overscreening. Providers identified potential strategies to reduce overscreening including patient and provider education around harms of screening, leveraging the electronic health record to identify women who may receive less health benefit from screening, customizing system-generated reminder letters, and organizing workgroups to develop standard processes of care around mammography screening. Conclusions Multi-level factors contributing to mammography overuse are dynamic, interconnected, and reinforced. To ensure equitable de-implementation, there is a need for more refined and empirical testing of theories, models, and frameworks for de-implementation with a strong patient-level component that considers the interplay between multilevel factors and the larger care delivery process.
Spectral deformations and exponential decay of eigenfunctions for the Neumann Laplacian on manifolds with quasicylindrical ends

Abstract We study spectral properties of the Neumann Laplacian on manifolds with quasicylindrical ends. In particular, we prove exponential decay of the non-threshold eigenfunctions and show that the eigenvalues can accumulate only at thresholds of the absolutely continuous spectrum and only from below. The non-threshold eigenvalues are also discrete eigenvalues of a non-selfadjoint operator.
Somatic mutations in the TRAIL receptor DR5 function as dominant negative mutations for some but not all agonists

Proc Amer Assoc Cancer Res, Volume 47, 2006 737 Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family that signals through two receptors, DR4 and DR5, providing a potential target for therapeutic intervention. Here we show that two point mutations in DR5 (E338K and L334F), which were identified in cancer patients, inhibit its ability to recruit the adaptor protein FADD. Cells expressing mutant versions of DR5 but wildtype versions of DR4 are resistant to some TRAIL pathway agonists indicating that the mutant DR5 can inhibit signaling through DR4 for some, but not all, activators of the pathway. Specifically, we found that cells expressing mutant DR5 receptors are resistant to apoptosis induced by therapeutic anti-DR5 antibodies but are sensitive to therapeutic anti-DR4 antibodies and retain sensitivity to some (not all) preparations of recombinant TRAIL. The mutant cells differ in their ability to activate downstream MAPK, p38 and NFκB signaling indicating that the mutations have different effects on some signaling pathways compared with others. These data show that different TRAIL pathway activators work by different mechanisms and may therefore provide a basis to choose specific activators of the TRAIL pathway to tailor treatments for particular patients.
Pricing and Hedging Variance Swaps on a Swap Rate

We solve the pricing and hedging problem for the generic variance swap on a swap rate. The solution is not limited to a specifc swap rate model approximation. In order to address the absence of arbitrage constraints and to preserve the model complexity, we develop an alternative approach to swap rate approximations.
Anesthetic and ethanol effects on spontaneously opening glycine receptor channels

Strychnine-sensitive glycine receptors mediate inhibitory neurotransmission occurring in the brain stem and spinal cord. Alcohols, volatile anesthetics and inhaled drugs of abuse are positive allosteric modulators of glycine receptor function, normally enhancing function only in the presence of glycine. A complication in studying allosteric actions on ligand-gated ion channels is in the dissection of their effects on neurotransmitter binding from their effects on channel opening. Mutation of an aspartate residue at position 97 to arginine in the glycine receptor alpha1 subunit simulated the effects of glycine binding, producing receptors that exhibited tonic channel opening in the absence of neurotransmitter; i.e. these receptors demonstrated a dissociation of channel opening from neurotransmitter binding. In these receptors, ethanol, enflurane, chloroform, halothane, 1,1,1-trichloroethane and toluene elicited inward currents in the absence of glycine. We previously identified mutations on ligand-gated ion channels that eliminate ethanol, anesthetic and inhalant actions (such as S267I on alpha1 glycine receptors). The double mutant (D97R and S267I) receptors were both constitutively active and resistant to the enhancing effects of ethanol and enflurane. These data demonstrate that ethanol and volatile anesthetics can affect glycine receptor channel opening independently of their effects on enhancing neurotransmitter binding.
Shared Outrage and Erratic Awards: The Psychology of Punitive Damages

An experimental study of punitive damage awards in personal injury cases was conducted, using jury-eligible respondents. There was substantial consensus on judgments of the outrageousness of a defendant's actions and of the appropriate severity of punishment. Judgments of dollar awards made by individuals and synthetic juries were much more erratic. These results are familiar characteristics of judgments made on unbounded magnitude scales. The degree of harm suffered by the plaintiff and the size of the firm had a pronounced effect on awards. Some judgmental tasks are far easier than others for juries to perform, and reform possibilities should exploit this fact.
DEEP-PLOW LIME STABILIZATION FOR PAVEMENT CONSTRUCTION

Deep-plow lime stabilization equipment and procedures for treating substantial thicknesses (18–36 in.) (30–90 cm) of in situ subgrade soil are described. Field study data and results are summarized and potential field applications are considered. It is concluded that deep-plow lime stabilization procedures can be successfully utilized in pavement construction if appropriate consideration is given to stabilization objectives and quality control requirements.
Lawyers in your living room! : law on television

From Perry Mason and The Defenders in the 1960’s to L. A. Law in the 80’s, The Practice and Ally McBeal in the 90’s, to Boston Legal, Shark, and Law & Order today, the television industry has generated an endless stream of dramatic series involving law and lawyers. As a result, most members of the public receive most of their information (and misinformation) about what lawyers and judges do and how legal institutions function from absorbing pop culture representations on television. This book features 36 chapters about legal television, both domestic and foreign, written by 40 different authors. In addition, it contains celebrity introductions by Sam Waterston and James Woods, two of the premiere actors portraying lawyers in contemporary television. The book covers the Judge Judy phenomenon (including her foreign counterparts) as well as shows that are not primarily about lawyers but feature important lawyer characters (such as The Simpsons or The West Wing). It also contains chapters about the production of dramatic legal shows, including writing and technical advising, and about legal ethics on television. The book concentrates on the personal and professional character of the lawyers -- which runs the gamut from fearless champions of the innocent to the sort of unethical or personally dysfunctional lawyers that the public loves to hate.
Ultrasonic Attenuation Measurement by Backscattering Analysis

Porosity in structural materials limits their ultimate strength and hence their utility. Recently several studies which discuss the porosity induced ultrasonic attenuation have appeared [1–8]. Porosity assessment by ultrasonic attenuation measurement involves two principal problems: first, how to relate the porosity induced ultrasonic attenuation to porosity parameters such as average pore radius and volume fraction, and second, how to separate the sought porosity induced attenuation from other components contributing to the actually measured total attenuation.
Endocrine ophthalmopathy: current ideas concerning etiology, pathogenesis, and treatment

ALTHOUGH the association of exophthalmos with goiter was recognized as early as the twelfth century (1), the modern focus on the constellation of hyperthyroidism, diffuse goiter, and endocrine ophthalmopathy is best attributed to the work of Caleb Parry (1825) (2), Robert Graves (1835) (3), and Carl von Basedow (1840) (4). Since their early descriptions a plethora of reports have been published detailing the clinical and histologic features of endocrine ophthalmopathy and coining a variety of colorful synonyms and eponyms (5, 6). There remained, however, a number of important unanswered questions. These deal with the nature of the inciting factor, the pathogenesis of the disease, the unique and often asymmetric involvement of extraocular muscles, the relationship between the eye disease and the thyroid abnormality, and the most rational and efficacious methods of treatment. We will review the clinical, anatomic, histologic, and immunologic features of endocrine ophthalmopathy particularly as they apply to...
Asymptotic analysis of growing crack stress/deformation fields in porous ductile metals and implications for stable crack growth

Asymptotic stress and deformation fields near a quasi-statically growing plane strain tensile crack tip in porous elastic-ideally plastic material, characterized by the Gurson-Tvergaard yield condition and associated flow rule, are derived for small uniform porosity levels throughout the range 0 to 4.54 percent. The solution configuration resembles that for crack growth in fully dense, elastically compressible, elastic-ideally plastic Huber-Mises material for this porosity range, except that the angular extents and border locations of near-tip solution sectors vary with porosity level, as do the stress and deformation fields within sectors. Increasing porosity is found to result in a dramatic reduction in maximum hydrostatic stress level, greater than that for a stationary crack; it also causes a significant angular redistribution of stresses, particularly for a range of angles ahead of the crack and adjacent to the crack flank. The near-tip deformation fields derived are employed to generalize a previously-developed, successful ductile crack growth criterion. Our model predicts that for materials having the same initial slopes of their crack growth resistance curves, but different levels of uniform porosity, higher porosity results in a substantially greater propensity for stable crack growth.
Design of an Implantable Device for Ocular Drug Delivery

Ocular diseases, such as, glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, and retinitis pigmentosa require drug management in order to prevent blindness and affecting million of adults in USA and worldwide. There is an increasing need to develop devices for drug delivery to address ocular diseases. This study focuses on the design, simulation, and development of an implantable ocular drug delivery device consisting of micro-/nanochannels embedded between top and bottom covers with a drug reservoir made from polydimethylsiloxane (PDMS) which is silicon-based organic and biodegradable polymer. Several simulations were carried out with six different micro-channel configurations in order to see the feasibility for ocular drug delivery applications. Based on the results obtained, channel design of osmotic I and osmotic II satisfied the diffusion rates required for ocular drug delivery. Finally, a prototype illustrating the three components of the drug delivery design is presented. In the future, the device will be tested for its functionality and diffusion characteristics.
Commentary: A decade of American RTS geography

Abstract Research on recreation, tourism and sport, conducted by geographers in North America (US and Canada) from 1988 to 1998 was compiled and the resulting bibliography can be found on the WWW at: . The context of North American geography is one of considerable diversity, though somewhat insular in subject matter. In addition to many general introductory and overview books and articles, much of the focus of recreation and tourism geographic research in North America has been applied rather than theoretical. This has been changing in the 1990s as the volume of research, especially on tourism topics, has increased considerably and more authors are publishing in leading general geography journals.
Relationship between the Disfluent Speech Behavior of Normal-Speaking Preschool Boys and Their Parents

To explore the relationship between the disfluent speech of normal-speaking preschool boys and their parents, samples of spontaneous speech were obtained from 24 preschool boys, their mothers, and ...
Ferromagnetic Spin Excitations in a One-Band Metallic Loop

A one-band periodic loop of $N$ electrons on $N$ sites interact by a two-body spin-independent potential, the band and the potential restricted so that only nearest-neighbor Wannier integrals occur, but otherwise arbitrary. The elementary excitations relative to the saturated ferromagnetic eigenstate are then found rigorously. The nature of the excitations and the condition for the stability of the ferromagnetic eigenstate are discussed. The excitations divide into continuum states, bound electron-hole (exciton) states below the band, and spin-wave states. The entire energy spectrum and the electron-hole correlation functions for the bound states are given. It is also shown that under certain conditions, the lowest-energy eigenstate among all one-spin-flip states has $S=\frac{1}{2}N$ and $M=\frac{1}{2}N\ensuremath{-}1$, where $S$ is the total spin and $M$ the $z$ component of spin quantum numbers. This result offers, therefore, a possible violation of the Lieb-Mattis theorem in the sub-space of one-band functions for a loop.
Using local conditions to reduce control overhead

Abstract In this paper, we replace the periodic transmission of control information by transmissions that depend on local network conditions. As a case study, we consider the proactive link state routing protocol OLSR running in a wireless network without infrastructure. Each node maintains a time series on its betweenness, a metric widely used in social network analysis. We interpret an anomaly in a node’s time series as a change in its role and use it to trigger the transmission of link state. In order to ensure throughput does not degrade by the use of dated information, we use a keep-alive timer whose interval takes into account other local conditions including the node speed, packet arrival rate, and number of flows served. We also measure the number of local link breaks and use it to trigger the transmission of neighbour information. ns-2 simulations comparing our proposed A + -OLSR to OLSR, A-OLSR, and Adaptive OLSR show a statistically significant increase in throughput and a decrease in control overhead. Our evaluation also considers packet losses and the use of CRAWDAD wireless traces to drive node movement.
A mechanistic study of electron transfer from the distal termini of electrode-bound, single-stranded DNAs

Electrode-bound, redox-reporter-modified oligonucleotides play roles in the functioning of a number of electrochemical biosensors, and thus the question of electron transfer through or from such molecules has proven of significant interest. In response, we have experimentally characterized the rate with which electrons are transferred between a methylene blue moiety on the distal end of a short, single-stranded polythymine DNA to a monolayer-coated gold electrode to which the other end of the DNA is site-specifically attached. We find that this rate scales with oligonucleotide length to the −1.16 ± 0.09 power. This weak, approximately inverse length dependence differs dramatically from the much stronger dependencies observed for the rates of end-to-end collisions in single-stranded DNA and through-oligonucleotide electron hopping. It instead coincides with the expected length dependence of a reaction-limited process in which the overall rate is proportional to the equilibrium probability that the end of t...
Anhedonia and emotional numbing in combat veterans with PTSD.

Abstract We explored relationships between anhedonia and posttraumatic stress disorder (PTSD) symptom clusters, including their role in predicting psychiatric comorbidity. Our measure of anhedonia was derived from an examination of the latent structure of the Beck Depression Inventory. We found evidence for a two-factor solution, leading to anhedonia and undifferentiated, global depressive symptoms scales. In primary analyses, anhedonia had a unique positive relationship with PTSD's emotional numbing symptoms and minimal relationships with other PTSD symptoms. Upon examining the incremental validity of appetitive functioning (i.e., anhedonia, emotional numbing) over and above aversive functioning (i.e., re-experiencing, avoidance, and hyperarousal PTSD symptoms) variables, greater emotional numbing increased the likelihood of being diagnosed with a major depressive disorder, and greater anhedonia increased the likelihood of being diagnosed with additional anxiety disorders and to a lesser extent, psychotic disorders. Results were consistent with research on the distinction of appetitive and aversive functioning, providing insight into the nature of PTSD.
Comparative Study of the Chemotactic Responses of Periodontal Ligament Cells and Gingival Fibroblasts to Polypeptide Growth Factors

Selective recruitment of periodontal ligament cells to a previously exposed root surface is believed to enhance periodontal regeneration. It has been hypothesized that competition from gingival fibroblasts may reduce the potential of periodontal regeneration. We compared the migratory responses of PDL cells and gingival fibroblasts to a variety of biologicals. Parallel experiments designed to examine the directed migration responses of both periodontal ligament cells (PDL cells) and gingival fibroblasts (GF) isolated from the same donors were conducted using Platelet Derived Growth Factor (PDGF), Insulin Like Growth Factor-I, -II (IGF-I, -II), Epidermal Growth Factor (EGF), Transforming Growth Factor-β (TGF-β), and the chemotactic factor derived from the conditioned culture media of PDL cells (termed PDL-CTX) as attractants.Both PDL cells and GF exhibited dose-dependent migratory responses when challenged with PDGF, IGF-I, IGF-II, EGF, and TGF-β. However, when these cells were challenged with PDL-CTX, onl...
ARE CORONAL LOOPS ISOTHERMAL

A controversy over the temperature distribution of coronal loops has arisen recently because different investigators using different techniques have obtained very different answers. Analysis of Solar and Heliospheric Observatory (SOHO) Extreme ultraviolet Imaging Telescope (EIT) and Transition Region and Coronal Explorer (TRACE) data using narrowband ratios to obtain temperature maps has produced several key publications that suggest that coronal loops may be isothermal. On the other hand, our analysis of the SOHO Coronal Diagnostics Spectrometer (CDS) spectral line data taken on 1998 April 20 for several pixels along a relatively isolated coronal loop on the southwest limb of the solar disk is clearly inconsistent with isothermal plasma along either the line of sight or the length of the loop. We have constructed a differential emission measure (DEM) distribution for each pixel; these distributions, taken together, suggested that the DEM-weighted temperature increases from the footpoints to the loop top. We convolved these DEM curves with the three different EIT coronal response functions. This gives us the intensity (in units of DN s-1) of what EIT would "see" in the 171, 195, and 284 A passbands if it were observing the CDS loop. We take a ratio of these values (171 A/195 A and 195 A/284 A), and use the regular EIT software to calculate a temperature at each pixel for each ratio. EIT "sees" a loop with an almost uniform temperature, but the derived temperatures are different for the different ratios. These uniform-temperature loops arise even though the actual temperature input is multithermal both along the line of sight and along the length of the loop. We suspect that these apparent uniform-temperature loops may be an unfortunate by-product of the simplistic filter-ratio method that is used for both EIT and TRACE temperature analysis. Our results indicate that narrow-passband EUV observations must be used in conjunction with other diagnostics to draw quantitative conclusions about the properties of coronal plasma.
Endothelin type A receptor antagonism restores myocardial perfusion response to adenosine in experimental hypercholesterolemia.

Abstract Experimental hypercholesterolemia is characterized by increased endothelin-1 (ET-1) activity and is associated with an attenuated myocardial perfusion response and an inappropriate increase in coronary microvascular permeability during episodes of increased myocardial demand. This study was designed to determine the effect of chronic selective ET type A (ET A ) receptor antagonism on coronary vascular response to simulated cardiac stress in experimental hypercholesterolemia. Twenty-one pigs were randomized to three groups: normal diet (N), high-cholesterol diet (HC), and HC diet plus ABT-627, a selective ET A receptor antagonist, (HC+ABT-627). After 12 weeks, cardiac electron beam computed tomography (EBCT) was performed before and during intravenous infusion of adenosine, and myocardial perfusion (ml/min per g) and coronary microvascular permeability index (arbitrary units) were calculated. Basal myocardial perfusion was similar in all groups (N: 0.91±0.10; HC: 0.95±0.08; HC+ABT-627: 1.03±0.09; P =0.64). Adenosine infusion led to a significant increase in myocardial perfusion in the N (1.32±0.15; P P =0.001). Basal permeability index did not differ between the groups (N: 1.56±0.13; HC: 1.34±0.19; HC+ABT-627: 1.62±0.10; P =0.38). Adenosine infusion significantly increased permeability index in HC pigs (2.29±0.22; P A receptor antagonism preserves myocardial perfusion response and coronary microvascular integrity during episodes of increased myocardial demand in experimental hypercholesterolemia, indicating an important role for the endogenous endothelin system in this disorder.
Effect of accessory pathway location on the efficiency of heating during radiofrequency catheter ablation

During radiofrequency catheter ablation of accessory pathways there is a poor correlation between applied power and temperature at target sites for catheter ablation. This study was designed to examine the relation between power and temperature during radiofrequency catheter ablation in patients with accessory pathways and to identify the factors that affect the efficiency of heating, defined as the ratio of applied power and temperature. Twenty-nine patients underwent radiofrequency catheter ablation of an accessory pathway. Among 257 energy applications, 108 were applied for ablation of a right-sided accessory pathway, 105 for a left-sided accessory pathway, and 44 for a posteroseptal accessory pathway. During each application of radiofrequency energy, temperature was continually monitored by use of an ablation catheter with a thermistor embedded in the tip of the distal electrode. During some applications of energy, fluctuations in temperature were observed. The average power, impedance, temperature, and efficiency of heating for all applications of radiofrequency energy was 37 +/- 11 W, 100 +/- 9 ohms, 53 +/- 9 degrees C, and 1.7 +/- 0.8 degrees C/W (range 0.9 degrees to 6.6 degrees C/W), respectively. The efficiency of heating varied by location (p < 0.0001), with the greatest efficiency of heating for posteroseptal energy applications (2.3 +/- 1.2 degrees C/W, which were significantly greater than for left-sided (1.8 +/- 0.8 degrees C/W; p < 0.01) or right-sided (1.2 +/- 0.4 degrees C/W; p < 0.0001) applications. Phasic fluctuation in temperature was observed during 127 (49%) energy applications, and the efficiency of heating was 1.5 +/- 0.7 degrees C/W.(ABSTRACT TRUNCATED AT 250 WORDS)
The Tools of Asclepius The Surgical Gear of the Greeks and Romans

Archaeological excavation and occasional chance finds have brought to light many of the surgical tools used in classical antiquity, especially those used in the Roman period. When these instruments are examined in connection with the medical authors of the time, they can frequently be identified and their purposes understood. Their number and variety show how surprisingly active and enterprising Greek and Roman surgeons were.
Spatial Autocorrelation Tests and the Classic Maya Collapse: Methods and Inferences

Abstract Spatial autocorrelation, resulting in pattern or structure in geographically distributed data, is discussed in theoretical and practical terms. Tests for spatial autocorrelation are presented, along with an explication of the relationship between autocorrelation models, the product-moment correlation coefficient and the spatial autocorrelation test statistic. Two archaeological examples illustrate the application of the auto-correlation test statistic. The first uses a hypothetical data set, which shows the type of map patterns that appear with various levels of spatial autocorrelation, and the second examines the terminal distribution of long-count-dated monuments at lowland Classic Maya sites. The results of the second example fail to support arguments for simple patterning in the cessation of the erection of these monuments and, by inference, in the Maya collapse itself. Finally, it is argued that while the identification of spatial autocorrelation is often the goal of spatial analyses, the presence of autocorrelation violates the assumptions of certain statistics used in such analyses.
EEO/AA and “doing good”: an exploratory study

Purpose – The purpose of this paper is to empirically examine the relationship between students’ perceptions of equal employment opportunity/affirmative action (EEO/AA) ideals and their perceptions of companies’ ability to meet goals using their corporate social responsibility (CSR) practices. The paper also examined the extent to which students’ support of EEO/AA relates to their community mindedness and attitudes toward volunteerism. Design/methodology/approach – The paper obtained data by surveying 895 students from a medium-sized university in the southern USA. Findings – Individuals generally supported EEO/AA, but differentiated between the two, with AA receiving less support. Those supporting EEO/AA were less likely to view a company’s CSR as instrumental in achieving the firm’s goals or its customers’ goals. EEO supporters reported more positive attitudes toward volunteering and tended to see more constraints to volunteering; however, EEO/AA attitudes mostly were unrelated to community mindedness o...
Southern analysis of DNA polymorphism among Dw subtypes of DR4.

Abstract DNA from individuals of four Dw subtypes of DR4 (Dw4, Dw10, Dw14, Dw15) were studied using Southern blotting to determine if subtype-specific DR β or DQ β restriction fragment polymorphism could be found. Although very little polymorphism was found among ten DR4 homozygous individuals (4 Dw4, 2 Dw10, 3 Dw14, 1 Dw15) using a DR β or a DQ β probe, restriction fragment polymorphism was easily detected between different DR types (DR1-DRw8). The possible evolutionary significance of the lack of Dw-associated polymorphism relative to DR-associated polymorphism is discussed.
A Communication Technique for Multipath Channels

Application of principles of statistical communication theory has led to a new communication system, called Rake, designed expressly to work against the combination of random multipath and additive noise disturbances. By coding the Mark-Space sequence of symbols to be transmitted into a wide-band signal, it becomes possible at the receiver to isolate those portions of the transmitted signal arriving with different delays, using correlation detection techniques. Before being recombined by addition, these separated signals are continuously and automatically processed so as to 1) apply to each an optimum weighting coefficient, derived from a measurement of the ionosphere response, and 2) introduce in each an appropriate delay such that they are all brought back into time coincidence. After a brief introduction, a functional description of the system is presented. There follows a review of the communication theory studies, which indicate that such systems have certain optimal properties. Details of design of an experimental prototype Rake system are followed by the results of limited field tests of this prototype. Conclusions and recommendations for future work are given.