cssi/SciSciGPT-SciSciNet huggingface dataset:
A Lattice Theory Approach to the Structure of Mental Models

Lattice theory is proposed to provide a formalism for the knowledge base used as a mental model by the operator of a complex system. The ordering relation \` $\geq $ ' is interpreted as \`is caused by', and the lattice becomes a representation of the operator's causal hypotheses about the system. A given system can be thought of causally in different ways (purposes, mechanics, physical form, etc.). Each gives rise to a separate lattice. These are related to each other and to an objective description of the structure and function of the physical system by homomorphic mappings. Errors arise when nodes on the mental lattices are not connected in the same way as the physical system lattice; when the latter changes so that the mental lattice no longer provides an accurate map, even as a homomorphism; or when inverse one-to-many mapping gives rise to ambiguities. Some suggestions are made about the design of displays and decision aids to reduce error.
Monitoring of Changes in Quality of Ground Watera

Ground water of acceptable quality is commonly interspersed with water of inferior quality. Water of inferior quality may be naturally occurring salty water commonly underlying fresh water, or it may be enclaves of contaminated water from wastes that lie in the fresh-water bodies. Disposal of wastes on and in the ground and pumping of water from wells cause a dispersion of contaminated water; migration of contaminated water toward wells may be spontaneously induced by the natural hydraulic gradient, or it may be induced artificially by the cone of depression about one or more wells. Economic methods of determining precisely the boundary zones between contaminated and uncontaminated water are not available. Much reliance is placed on monitoring wells. A prerequisite to monitoring is a synthetic hydrogeologic framework or model in which the behavior of the contaminated water is conceived. Such a conceptual model, using pertinent data that are available, helps to assess the need for monitoring and to guide a monitoring program for optimum results. Unplanned, indiscriminate monitoring of water from wells is expensive, inefficient, and fallible. The need for monitoring will increase in the future; yet, the proper objective is to improve the technology of determining the distribution of contaminated water so that monitoring can be minimized and conducted with optimum results.
Early- and late-migrating cranial neural crest cell populations have equivalent developmental potential in vivo

We present the first in vivo study of the long-term fate and potential of early-migrating and late-migrating mesencephalic neural crest cell populations, by performing isochronic and heterochronic quail-to-chick grafts. Both early- and late-migrating populations form melanocytes, neurons, glia, cartilage and bone in isochronic, isotopic chimeras, showing that neither population is lineage-restricted. The early-migrating population distributes both dorsally and ventrally during normal development, while the late-migrating population is confined dorsally and forms much less cartilage and bone. When the late-migrating population is substituted heterochronically for the early-migrating population, it contributes extensively to ventral derivatives such as jaw cartilage and bone. Conversely, when the early-migrating population is substituted heterochronically for the late-migrating population, it no longer contributes to the jaw skeleton and only forms dorsal derivatives. When the late-migrating population is grafted into a late-stage host whose neural crest had previously been ablated, it migrates ventrally into the jaws. Thus, the dorsal fate restriction of the late-migrating mesencephalic neural crest cell population in normal development is due to the presence of earlier-migrating neural crest cells, rather than to any change in the environment or to any intrinsic difference in migratory ability or potential between early- and late-migrating cell populations. These results highlight the plasticity of the neural crest and show that its fate is determined primarily by the environment.
Decoding the Golay code with Venn diagrams

A decoding algorithm, based on Venn diagrams, for decoding the (23, 12, 7) Golay code is presented. The decoding algorithm is based on the design properties of the parity sets of the code. As for other decoding algorithms for the Golay code, decoding can be easily done by hand. >
Publishing Active Workflows to Problem-Focused Web Spaces

We present a new paradigm for publishing scientific workflows to the Web. Publishing in this system involves not only creating a Web space for running the workflow on demand, but also the ability for the publisher to convey expertise about its use by providing ways to focus attention on problem-relevant parameters, inputs and outputs. As part of the publishing step we include the ability to configure visualizations for specific outputs of the workflow. The resulting system is a Web based environment focused on the ability to publish existing workflows so that other users in the community can execute those workflows and visualize the results from the Web. Workflow executions and visualizations can be shared with the community along with workflow definitions.
THE ‘COMPARATIVE INSTITUTIONAL’ THEORY OF THE FIRM: SOME IMPLICATIONS FOR CORPORATE STRATEGY*

This article outlines a rationale for the existence of firms and derives its implications for corporate strategy. It argues that one important source of sustainable rents is the ability of firms to reduce the costs they experience in organizing both internal and external transaction below those of their rivals.
Spin-up of a strongly stratified fluid in a sphere

A linear theory is developed for the spin-up of a compressible fluid, stratified by a spherical gravity field. Numerical results are obtained for the case of strong stratification (BruntVisl frequency N much greater than the rotation frequency 0). The interior flow is solved in terms of a set of angular eigenfunctions which have been obtained numerically. The principal result is that the spin-up is limited to a layer adjacent to the spherical boundary, the thickness of the layer being of the order of L(0/N), where L is the radius of the boundary. The solution is qualitatively similar to that found by Holton (1965), Walin (1969), and Sakurai (1969a, b) for a stratified fluid in a cylinder. The thickness of the spin-up layer diminishes with latitude , the variation being described roughly by the formula L0| sin |/N. For the case of slow continuous spin-up, the Ekman suction velocity has been calculated, and the results show that || = 24 is the dividing angle between suction (|| > 24) and blowing (|| < 24).
The Cross-Coupled Pair?Part III [A Circuit for All Seasons]

In this article, we study applications of the cross-coupled pair (XCP) in analog and RF circuits. The XCP can serve as a negative resistance or a negative impedance converter in small-signal operation, or a regenerative circuit in large-signal operation.
The prevalence of BANA-hydrolyzing periodontopathic bacteria in smokers.

Smoking has been identified as a risk factor for development of peri- odontal disease and a strong indicator for treatment failure in periodontal patients. This study examined 172 patients categorized as current smokers (n=SS), pre- vious smokers (n=38) or individuals that had never smoked (n=79). A total of 670 interproximal plaques collected with a wooden toothpick were analyzed for hy- drolysis of the synthetic trypsin substrate benzoyl-DL-arginine naphthylamide (BANA). About 95% of the BANA hydrolysis by plaque is due to the presence of one or more of the periodontopathogens, P. gingivalis, T. denticola or B. forsythus. Gingival health was measured using the papillary bleeding score (PBS). Current smokers had less gingival bleeding than previous smokers or those who had never smoked (20% versus 41% and 25%, respectively). Plaque removed from non-bleeding sites in current smokers were 1 1 X more likely to have a positive BANA reaction when compared to plaque removed from non-bleeding sites in individuals who never smoked. A significant positive relationship exists between smoking and colonization by the BANA periodontopathogens. Smoking may select for these periodontopathic species in the plaque and may be one reason why smoking is a risk factor in periodontal disease development.
Cellular dynamics in the jejunum of essential fatty acid deficient mice

The population dynamics of the jejunal epithelium of mice maintained on a semi-synthetic diet deficient in the essential fatty acids (EFA) has been investigated. Colchicine was employed to collect mitotic figures for the determination of mitotic indices. Twenty-five crypts in longitudinal section were counted per animal and the mean mitotic index computed as the number of mitoses per total number of crypt cells. EFA-deficient animals had a mean mitotic index of 36.56 as compared with 26.51 and 16.74 for the linoleic acid-supplemented and chow-fed control animals, respectively. Counts of the number of epithelial cells on one side of a villus and crypt indicated that the height of the villi, but not the crypts, of the EFA-deficient animals was significantly lower than either control group. In the EFA-deficient animals the mean percentage of villi having extrusion zones exceeded that of both control groups. Radioautography demonstrated that 36 hours after injection of tritiated thymidine the majority of villi in the EFA-deficient animals were labeled at their tips, whereas in control samples label was restricted to the lower one-half to three-fourths of the villus. Thus, EFA-deficiency induces increased rates of mitosis, migration and sloughing, resulting in alterations in villous architecture.
Competition within Physical Education: Using Sport Education and Other Recommendations to Create a Productive, Competitive Environment

The use of Sport Education by physical education teachers to implement developmentally appropriate competitive activities is explored. The potential positive and negative consequences of competitive activities are discussed along with suggestions for teachers on how they can foster an appropriate competitive environment in physical education.
Of Sodomy and Cannibalism: Dehumanisation, Embodiment and the Rhetorics of Same‐Sex and Cross‐Species Contagion

This article explores ideas of the ‘human’ in discourses surrounding the AIDS epidemic, from the 1980s to the present. It compares two sequential lines of thought: first, the notion of AIDS as the result of ‘unnatural’ gender behaviours and queer sexualities; and second, the notion of AIDS and other zoonotics (cross-species diseases) as the result of non-western dietary practices and social mores. In the first case, the early years of the AIDS crisis are traced through the languages of sexual perversity utilised by the popular press and the Christian right. In the second case, the later years of the epidemic are traced, once the ‘roots’ of the virus became tied to Africa, and carriers became bestialised in narratives that located HIV as a consequence of unnatural, or inhuman, interactions with the animal world. The article argues that we have witnessed a paradigm shift in the didactics of the epidemic, from a narrative of sexual impropriety to one that also includes a narrative of dietary impropriety, each of which consistently relies upon a clear dichotomy between the human and the inhuman.
Ecological species groups of landform-level ecosystems dominated by jack pine in northern Lower Michigan, USA

A combination of field and tabular methods and multivariate analyses were used to develop groups of ground flora species (i.e., ecological species groups) that characterize and distinguish highly disturbed, landform-level ecosystems dominated by jack pine in northern Lower Michigan. The endangered Kirtland’s warbler formerly or currently occupied the large glacial landforms for which species groups were developed. Eight such ecological species groups were created using 31 woody and herbaceous species sampled in 144 plots within a 20,000 km 2 geographic region of uniform climate and regional physiography. The groups were initially constructed using subjective, observation-based groupings of species with similar presence and abundance along soil moisture and fertility gradients. Species groups were corroborated using TWINSPAN and detrended correspondence analysis, and the environmental conditions indicated by each were described and contrasted based upon field observations and canonical correspondence analysis. Two of the eight species groups indicated very dry, infertile sites, and one was indicative of a very broad range of sites dominated by jack pine. The remaining five groups reflected a relatively gentle environmental gradient within the set of ecosystems we sampled, indicating small differences along a soil moisture gradient and less so along a soil fertility and light availability gradient. The groups were applied successfully for the majority of an area that had been repeatedly logged and/or burned for at least 120 years. In addition, the groups were successful when tested on sites with highly disturbed upper soil strata furrowed for the establishment of plantations between the 1960s and 1980s. Within the boundaries of the regional ecosystems for which they were developed, ecological species groups reflect the integrated effects of multiple site factors that control the height growth rates of jack pine trees that, in turn, determine the duration of Kirtland’s warbler occupancy. While usually applied at the scale of ecosystem types, our results demonstrate that ecological species groups may also provide the ecological basis for distinguishing ecosystems at broader scales. When examined simultaneously in the field with physiography, microclimate, and soil factors, the groups are therefore useful in identifying and classifying ecosystem units at the scale of landforms, the appropriate scale of management for the Kirtland’s warbler.
Prospective multicenter clinical evaluation of AMPLICOR and COBAS AMPLICOR hepatitis C virus tests.

We conducted a multicenter clinical evaluation of the second versions of the manual AMPLICOR and the semiautomated COBAS AMPLICOR tests for hepatitis C virus (HCV) RNA (Roche Molecular Systems, Inc., Pleasanton, Calif.). The performance characteristics of these HCV RNA tests for diagnosis of active viral infection were determined by comparison to anti-HCV serological test results, alanine aminotransferase levels, and liver biopsy histology results. A total of 878 patients with clinical or biochemical evidence of liver disease were enrolled at four hepatology clinics. A total of 1,089 specimens (901 serum and 188 plasma) were tested with the AMPLICOR test. Sensitivity compared to serology was 93.1% for serum and 90.6% for plasma. The specificity was 97% for serum and 93.1% for plasma. A total of 1,084 specimens (896 serum and 188 plasma) were tested with the COBAS test. Sensitivities for serum and plasma were the same as with the AMPLICOR test. The specificity was 97.8% for serum and 96.6% for plasma. Of the 69 specimens with false-positive and false-negative AMPLICOR test results relative to those of serology, alternative primer set (APS) reverse transcription (RT)-PCR analysis showed that the AMPLICOR test provided the correct result relative to the specimens containing HCV RNA in 64 (92.7%) specimens. Similarly, 66 of 67 (98.5%) false-positive and false-negative COBAS test results were determined to be correct by APS RT-PCR analysis. There were no substantive differences in clinical performances between study sites, patient groups, specimen types, storage conditions (−20 to −80°C versus 2 to 8°C), or anticoagulants (EDTA versus acid citrate dextrose) for either test. Both tests showed >99% reproducibility within runs, within sites, and overall. We conclude that these tests can reliably detect the presence of HCV RNA, as evidence of active infection, in patients with clinical or biochemical evidence of liver disease.
Infinite Needs–Finite Resources: The Future of Healthcare

The single greatest challenge facing managers in the developed countries of the world is to raise the productivity of knowledge and service workers. This challenge, which will dominate the management agenda for the next several decades, will ultimately determine the competitive performance of companies. Even more important, it will determine the very fabric of society and the quality of life of every industrialized nation. … Unless this challenge is met, the developed world will face increasing social tensions, increasing polarization, increasing radicalization, possibly even class war.
A Cryptic Case: Isolated Cerebral Mucormycosis.

PRESENTATION A rare infection raging within the brain of a 50-year-old African-American man was impossible to diagnose until after his death. He presented to the emergency department after the acute onset of garbled speech, confusion, right-arm weakness, and right facial droop. His medical history was significant for poorly controlled diabetes mellitus and polysubstance abuse, including intravenous drug abuse. He had never had a stroke, had no sick contacts, and had not traveled recently.
CYCLIC AMP REGULATES PDGF-STIMULATED SIGNAL TRANSDUCTION AND DIFFERENTIATION OF AN IMMORTALIZED OPTIC-NERVE-DERIVED CELL LINE

To facilitate the study of the molecular events underlying the development of optic-nerve-derived oligodendrocytes and their growth-factor-related signal transduction events, we immortalized perinatal rat optic nerve cells with a temperature-sensitive simian virus 40 large T-antigen, carrying the tsA58 and U19 mutations, via a retrovirus vector. The line, tsU19-9, was selected on the basis of the expression of the neural precursor marker nestin. At the permissive temperature, 33 degreesC, tsU19-9 cells had a flat epithelial morphology. In contrast, following exposure to platelet-derived growth factor (PDGF), a factor important in the lineage progression of oligodendrocytes, or in the presence of dibutyryl cyclic AMP at 39 degreesC (the non-permissive temperature), the cells underwent morphological and antigenic differentiation to cells characteristic of the oligodendrocyte lineage. We used this cell line to investigate the binding characteristics of PDGF and related signalling cascades. Competition binding, phosphoinositide hydrolysis and intracellular Ca2+ mobilization assays all demonstrated that the three different isoforms of PDGF (AA, AB and BB) bound to and acted on the cell line. Overnight exposure to forskolin, a treatment that initiated morphological and phenotypic progression into an oligodendrocyte lineage, decreased PDGF-BB-induced intracellular Ca2+ mobilization and inhibited basal and PDGF-stimulated [3H]thymidine incorporation. Our results demonstrate that tsU19-9 may serve as a resource to study early optic-nerve oligodendrocyte development.
THE ISSUE OF NAMIBIAN INDEPENDENCE

SOUTH AFRICA HAS administered the territory of South West Africa (Namibia) for over half a century, but recently has agreed to grant independence on the basis of democratic elections. International concern over South Africa's administration of the mandated territory has been a paticular cause of friction with most of the rest of the world. Because Namibia and South Africa share a common border, events in Namibia have a direct bearing upon South African national security. Pretoria asserts that current aggressive moves in Africa by the Soviet Union, including the activities of Soviet sponsored organizations within Zimbabwe and Namibia, are clear and present dangers to South Africa. The purpose of this article is to examine the chief actors, and explore the pertinent problems, involved in the issue of Namibian independence.
Text-Mess: There is no Textual Basis for Application of the Takings Clause to the States

There can be no denying that the entire country has witnessed loud, frequent, and riveting fireworks following the United States Supreme Court's decision in the Kelo v. City of New London. 1 Much of the reaction may have been orchestrated by well-organized critics of the decision, but the stark and vehement differences among the Justices surely helped to trigger a striking reaction full of public outcry, many legislative responses, substantial commentary, and an unusual number of learned symposia -- such as this one.
Observation of Multiple Crystal-to-Crystal Transitions in a New Reduced Vanadium Oxalate Hybrid Material, Ba3[(VO)2(C2O4)5(H2O)6]·(H2O)3, Prepared via a Mild, Two-Step Hydrothermal Method

A new reduced vanadium oxalate, Ba3[(VO)2(C2O4)5(H2O)6]·(H2O)3, 1, was synthesized via a two-step, mild hydrothermal method using oxalic acid as the reducing agent. This compound undergoes multiple single-crystal to single-crystal phase transitions as a function of water content to form Ba3[(VO)2(C2O4)5(H2O)4]·(H2O)2, 2, and Ba3[(VO)2(C2O4)5(H2O)2], 3, after heating 1 to 50 and 100 °C, respectively. In addition, exposing 1 to a vacuum for 12 h also transforms it into 2, but not 3. All three compositional variants were structurally characterized by single crystal X-ray diffraction and are found to crystallize in the monoclinic space groups of C2/c and P21/c, for 1 and 2, and 3, respectively. Vanadium in these structures retains the +4 oxidation state, indicating exceptional crystal stability. The magnetic susceptibility of these compounds was measured, and all three materials were found to be paramagnetic down to 2 K. Compound 1 was further characterized by IR, UV-vis spectroscopy, and thermal analysis.
A Non-Profit University And A For-Profit Consulting Company Partner To A Offer A New Masters Degree

The University of San Diego, School of Business Administration (non-profit university) and the Ken Blanchard Companies (for profit management consulting company) teamed to create the Master of Science in Executive Leadership at USD. Fusing a traditional non-profit university faculty and staff with a for-profit consulting company created a plethora of financial, cultural, and marketing issues. These issues were solved through a creative and collaborative process. Ultimately the new masters degree thrived both financially, and developed into a popular program for upwardly mobile business executives.
A high fat diet alters metabolic and bioenergetic function in the brain: A magnetic resonance spectroscopy study.

Diet-induced obesity and associated metabolic effects can lead to neurological dysfunction and increase the risk of developing Alzheimer's disease (AD) and Parkinson's disease (PD). Despite these risks, the effects of a high-fat diet on the central nervous system are not well understood. To better understand the mechanisms underlying the effects of high fat consumption on brain regions affected by AD and PD, we used proton magnetic resonance spectroscopy ((1)H-MRS) to measure neurochemicals in the hippocampus and striatum of rats fed a high fat diet vs. normal low fat chow. We detected lower concentrations of total creatine (tCr) and a lower glutamate-to-glutamine ratio in the hippocampus of high fat rats. Additional effects observed in the hippocampus of high fat rats included higher N-acetylaspartylglutamic acid (NAAG), and lower myo-inositol (mIns) and serine (Ser) concentrations. Post-mortem tissue analyses revealed lower phosphorylated AMP-activated protein kinase (pAMPK) in the striatum but not in the hippocampus of high fat rats. Hippocampal pAMPK levels correlated significantly with tCr, aspartate (Asp), phosphoethanolamine (PE), and taurine (Tau), indicating beneficial effects of AMPK activation on brain metabolic and energetic function, membrane turnover, and edema. A negative correlation between pAMPK and glucose (Glc) indicates a detrimental effect of brain Glc on cellular energy response. Overall, these changes indicate alterations in neurotransmission and in metabolic and bioenergetic function in the hippocampus and in the striatum of rats fed a high fat diet.
Crawford v Los Angeles Unified School District Education Board 50th Anniversary (Crawford is 50), Timeline Showing UCLA Special Collections and their Relation to Significant Events in the Litigation

A timeline comparing UCLA special collections and persons to the major procedural events in this school desegregation case. UCLA is planning an event to commemorate this important school desegregation case. In a symposia, presenters can be expected to contribute significant works that will explore enduring social science, policy and legal remedies.
Evidence-based management of dental injury: Case presentations

Dental trauma is one of the most frequent types of facial injuries occurring in children and adolescents. Appropriate management through an evidence based philosophy is critical in ensuring a best practice rendered. For this presentation, the following cases - clinical crown fracture, avulsion, and root fracture - are used to demonstrate and review the current literature and guidelines accepted as evidence based dentistry in the management of dental trauma.
Planning an interview: What do candidates want?

Recrutement de personnel dans une bibliotheque: planification de l'entretien, destinee a augmenter les chances de retenir les meilleurs candidats
The Dutch Republic

Although Reysen’s title page announces that it features 26 years of Struys’s travels, it describes in fact no more than the ten years that the sailmaker spent in faraway regions. By the time the book was published its alleged author had lived for four-fifths of his almost fifty years in the Dutch Republic. Its society’s habitus and economic ethos informed the behaviour of the historical Jan Struys and determined the depiction of him in Reysen’s pages. In understanding Struys and Reysen’s most fascinating and revealing voyage to Muscovy and Iran (as well as Reysen’s creation and Struys’s later years), the context of this anomalous seventeenth-century country needs to be taken into account.
When negative is positive.

the purpose of this brief editorial comment is to highlight the importance of what is regrettably termed “negative data.” The definition of negative data is straightforward: the failure to reject the null hypothesis. But is such an outcome any less important than the alternative? If not, then
Varicella Zoster Encephalomyelitis in an Immunocompetent Patient without Rash (P03.248)

OBJECTIVE: To report a rare case of severe Varicella Zoster virus (VZV) encephalomyelitis in an immunocompetent patient and the first of its kind without the typical rash, and to highlight consideration of this entity in cases with similar clinical presentations. BACKGROUND: VZV can present with varying neurological manifestations, the most common being post-herpetic neuralgia. A rash may or may not present with VZV infection, however typically immunocompetent patients present with simply a rash and distant, minute areas of small-vessel vasculitis. Conversely, immunocompromised patients display more disseminated disease of small vessels including vasculopathy, myelopathy, Ramsay-Hunt syndrome, cerebellitis, and rarely, encephalomyelitis. VZV encephalomyelitis is a unique entity, with the proposed underlying pathophysiological process that of small vessel vasculitis, inflammation and subsequent demyelination. It was traditionally thought that VZV encephalomyelitis was a disease of the immunocompromised, however there have been increasing numbers involving immunocompetent patients as more clinicians utilize cerebrospinal (CSF) PCR and antibody studies to diagnose VZV as a cause for neurologic disease. To date, there have been fewer than 3 case reports of VZV encephalomyelitis involving immunocompetent patients. DESIGN/METHODS: The patient9s history, exam, clinical and laboratory data and MRI imaging at presentation, as well as longer term follow up investigations were performed and reviewed, including an extensive literature search on previous case reports and publications in this area. RESULTS: CSF, PCR and viral studies as well as correlates on brain and spinal cord imaging and improvement with anti-virals, prove varicella zoster encephalomyelitis in this patient presenting with a progressive paraparesis and myelopathy, encephalitis and cranial neuropathies. CONCLUSIONS: This is the first report of a patient with extensive VZV encephalomyelitis involving the spinal cord, brain, meninges, and cranial nerves without an identifiable rash, and highlights the importance of early consideration of this diagnosis in order to prevent the often aggressive neurologic deterioration seen in these cases. Disclosure: Dr. Lynch has nothing to disclose. Dr. Agarwal has nothing to disclose. Dr. Hadley has nothing to disclose. Dr. Vullaganti has nothing to disclose.
An interview on subalternity (published in partnership with Éditions Amsterdam)

Etienne Balibar: Of course I would like to say what a pleasure it is for me to be here with our friends from Editions Amsterdam of the bookstore Le Merle Moqueur of Maison Payot represented by Gaya...
SDfR -Service discovery for multi-robot systems

Multi-robots systems require dedicated tools and models for their design and the deployment. Our approach proposes service-oriented architecture that can simplify the development and deployment. In order to solve the problem of neighbors and service discovery in an ad-hoc network, the fleet robot needs a protocol that is able to constantly discover new robots in its coverage area. To this end we propose a robotic middleware, SDfR, that is able to provide service discovery. This protocol is an extension of the Simple Service Discovery Protocol (SSDP) used in Universal Plug and Play (UPnP) used in dynamic networks generated by the mobility of the robots. Even if SDfR is platform independent, we propose a ROS (ROS, 2014) integration in order to facilitate the use. We evaluate a series of overhead benchmarking across static and dynamic scenarios. We also present some use-cases where our proposal was successfully used.
The Multipurpose Tool of Social Media: Applications for Scientists, Science Communicators, and Educators.

Abstract Social media has become the fastest way to disseminate new information, share personal experiences, and discuss scientific reports in an open-access setting. It acts as an aggregator of news and reports, a platform for education, a means of public outreach, and a tool for scientific research. Each social media service offers unique communication benefits. This review discusses how scientists are using social media to inform and learn from social media communities, concentrating on microbiology and infectious disease.
Seeking (and Finding) Biased Ligands of the Kappa Opioid Receptor

The discovery and characterization of two classes of kappa opioid receptor agonists that are biased for G protein over βarrestin signaling are described.
Epigenetic Alterations in Human Papillomavirus-Associated Cancers

Approximately 15–20% of human cancers are caused by viruses, including human papillomaviruses (HPVs). Viruses are obligatory intracellular parasites and encode proteins that reprogram the regulatory networks governing host cellular signaling pathways that control recognition by the immune system, proliferation, differentiation, genomic integrity, and cell death. Given that key proteins in these regulatory networks are also subject to mutation in non-virally associated diseases and cancers, the study of oncogenic viruses has also been instrumental to the discovery and analysis of many fundamental cellular processes, including messenger RNA (mRNA) splicing, transcriptional enhancers, oncogenes and tumor suppressors, signal transduction, immune regulation, and cell cycle control. More recently, tumor viruses, in particular HPV, have proven themselves invaluable in the study of the cancer epigenome. Epigenetic silencing or de-silencing of genes can have cellular consequences that are akin to genetic mutations, i.e., the loss and gain of expression of genes that are not usually expressed in a certain cell type and/or genes that have tumor suppressive or oncogenic activities, respectively. Unlike genetic mutations, the reversible nature of epigenetic modifications affords an opportunity of epigenetic therapy for cancer. This review summarizes the current knowledge on epigenetic regulation in HPV-infected cells with a focus on those elements with relevance to carcinogenesis.
Victimization, Aggression, and Other Problem Behaviors: Trajectories of Change Within and Across Middle School Grades.

This study examined trajectories of victimization and problem behaviors within and across three grades of middle school. Participants were 2,166 adolescents from three urban middle schools in the United States who completed measures of victimization, physical and relational aggression, substance use, and delinquent behavior. Latent curve analyses modeled changes in each construct across 12 waves collected every 3 months. In each case, the best-fitting model required separate linear slopes to represent changes within each grade and a factor representing decreases in the summers. Positive cross-construct correlations were found for intercepts, linear slopes, and measures within waves. The findings suggest strong associations among victimization and problem behaviors, and individual differences in their patterns of change both within and across grades.
Viewpoints: how the hippocampus contributes to memory, navigation and cognition

The hippocampus serves a critical function in memory, navigation, and cognition. Nature Neuroscience asked John Lisman to lead a group of researchers in a dialog on shared and distinct viewpoints on the hippocampus.
Sucrose withdrawal induces depression and anxiety-like behavior by Kir2.1 upregulation in the nucleus accumbens

Dieting induces depression and anxiety among other emotional symptoms. Animal models indicate that repeated access to palatable foods such as sugar induces depression and anxiety-like behavior when the food is no longer available. However, the neurobiological mechanisms of how dietary restriction influences mood have not been fully understood. We used the two-bottle sucrose choice paradigm as an overeating and withdrawal model. Withdrawal after lengthy sucrose overeating elicited depression and anxiety-like behavior, which was reversed by sucrose reinstatement. In the nucleus accumbens (NAc) of sucrose withdrawal animals, dopamine levels and cAMP response element binding protein (CREB) activity were significantly reduced, while the inwardly rectifying K+ channel, Kir2.1, was significantly elevated. In addition, overexpression of Kir2.1 selectively in neurons expressing dopamine D1 receptors was sufficient to induce negative mood-linked behavior in the absence of sucrose overeating experience. As elevated K+ channels reduce neuronal excitability, a sucrose withdrawal-induced increase in Kir2.1 expression is able to decrease NAc activity, which provides a cellular basis for depression and anxiety-like behavior in animals.
The Ripple Effects of Vulnerability: The Effects of a Robot's Vulnerable Behavior on Trust in Human-Robot Teams

Successful teams are characterized by high levels of trust between team members, allowing the team to learn from mistakes, take risks, and entertain diverse ideas. We investigated a robot’s potential to shape trust within a team through the robot’s expressions of vulnerability. We conducted a between-subjects experiment (N = 35 teams, 105 participants) comparing the behavior of three human teammates collaborating with either a social robot making vulnerable statements or with a social robot making neutral statements. We found that, in a group with a robot making vulnerable statements, participants responded more to the robot’s comments and directed more of their gaze to the robot, displaying a higher level of engagement with the robot. Additionally, we discovered that during times of tension, human teammates in a group with a robot making vulnerable statements were more likely to explain their failure to the group, console team members who had made mistakes, and laugh together, all actions that reduce the amount of tension experienced by the team. These results suggest that a robot’s vulnerable behavior can have "ripple effects" on their human team members’ expressions of trust-related behavior.
Role of adjuvant external beam radiotherapy and chemotherapy in one versus two or more node-positive vulvar cancer: A National Cancer Database study.

Abstract Background and purpose Inguinal lymph node involvement is considered the most important prognostic risk factor for survival in vulvar cancer. However, controversy exists concerning the optimal adjuvant therapy for node-positive disease. This study sought to identify the optimal adjuvant therapy for each subset of women with node-positive disease. Material and methods The National Cancer Database (NCDB) was queried to identify women with inguinal node positive vulvar cancer. Survival analysis was performed using log-rank test, the Kaplan–Meier estimates, and Cox proportional hazards to both clarify prognosis and identify the benefit of each treatment modality in individual subsets of women. Results A total of 2779 women with inguinal node positive vulvar cancer were identified. On multivariate Cox model hazard ratio, radiotherapy yielded a survival advantage for women with one positive node (HR 0.81, p = 0.027) and two or more positive nodes (HR = 0.59, p Conclusions All patients with node positive disease benefited from radiotherapy. By contrast, only those with 2 or more positive nodes benefited from the addition of chemotherapy to radiotherapy.
Study of the Transferrin Receptor Using a Cytotoxic Human Transferrin-Ricin a Chain Conjugate

The A chain of ricin which catalytically inactivates eukaryotic ribosomes inhibits cellular protein synthesis only after entering the cell. Although attachment of pure A chain to cell membranes has not been demonstrated (Raso, 1981), it is toxic at high concentrations indicating that cells can inefficiently internalize this 30,000 MW protein. Cytotoxicity is enhanced 103–105-fold however by recombining A chain either with its natural B chain subunit or with alternative carriers which deliver it to the cell surface and facilitate access to ribosomes within the cytoplasm. Thus, cyto-toxins possessing different cell receptor selectivities can be designed by coupling A chain to antibody or ligand carriers with appropriately chosen specificity characteristics. This controlled cytotoxic action has stimulated interest from the standpoint of eliminating undesirable cells for therapeutic reasons but is equally important for cell biology studies.
ELK Key Distribution

Broadcast streams require authentication and confidentiality. Previous chapters present protocols for efficient authentication and signature protocols for broadcast streams. This chapter discusses confidentiality and access control.
Long Wavelength Bulk and Surface Spin Waves in Metallic Superlattices

At long wavelength where exchange interactions play a small role, and the dominant contribution to the excitation energy of the spin waves in a ferromagnet comes from the external Zeeman field and the demagnetizing field set up by the motion of the spins, the surface spin waves, also called the Damon-Eschbach mode, [1] have unique characteristics. Unlike the short wavelength, exchange-dominated surface spin waves, these dipolar surface magnons lie in frequency above the bulk bands and are unidirectional in nature. This effect shows up very well in Brillouin scattering measurements on ferromagnetic materials for both the case of the film [2] and the semi-infinite solid [3], where the surface magnon appears on either the Stokes or the anti-Stokes part of the spectrum, depending on whether the Zeeman field is parallel or antiparallel with respect to the saturation magnetization of the ferromagnet. The calculated light scattering spectra [4], in agreement with the experimental results, show the surface magnon peak to be much more intense than those due to the bulk magnons.
Low-Cost High-Efficiency Single-Stage Solid-State Transformer for Lighting Applications

This paper presents a low-cost high-efficiency single-stage 480 V rms to 264 V rms solid-state transformer (SST) for lighting applications. The proposed SST is based on center-point-clamped (CPC) ac-ac buck converter topology. A comprehensive cost and efficiency optimization methodology is developed to help identify the most appropriate SST design across a design space comprising various switch structures, a range of operating frequencies, and different inductance values. For the selected implementation, a novel switching scheme is introduced that ensures smooth inductor current commutation during switching transitions, and also reduces zero-crossing distortion in the input current. Furthermore, an active voltage balancing scheme is developed to compensate for any imbalances between the two stacked input capacitors to ensure robust converter operation. A prototype 600-W solid-state transformer based on the proposed optimization, designed to operate at an input voltage of 480 V rms and an output voltage of 264 V rms is built and tested. The prototyped converter achieves a peak efficiency of 96%, maintains an efficiency of above 92% across a 3:1 output power range, and has a power density of 40 W/in3.
Quantifying inequities in US federal response to hurricane disaster in Texas and Florida compared with Puerto Rico

If disaster responses vary in their effectiveness across communities, health equity is affected. This paper aims to evaluate and describe variation in the federal disaster responses to 2017 Hurricanes Harvey, Irma and Maria, compared with the need and severity of storm damage through a retrospective analysis. Our analysis spans from landfall to 6 months after landfall for each hurricane. To examine differences in disaster responses across the hurricanes, we focus on measures of federal spending, federal resources distributed and direct and indirect storm-mortality counts. Federal spending estimates come from congressional appropriations and Federal Emergency Management Agency (FEMA) records. Resource estimates come from FEMA documents and news releases. Mortality counts come from National Oceanic and Atmospheric Administration (NOAA) reports, respective vital statistics offices and news articles. Damage estimates came from NOAA reports. In each case, we compare the responses and the severity at critical time points after the storm based on FEMA time logs. Our results show that the federal government responded on a larger scale and much more quickly across measures of federal money and staffing to Hurricanes Harvey and Irma in Texas and Florida, compared with Hurricane Maria in Puerto Rico. The variation in the responses was not commensurate with storm severity and need after landfall in the case of Puerto Rico compared with Texas and Florida. Assuming that disaster responses should be at least commensurate to the degree of storm severity and need of the population, the insufficient response received by Puerto Rico raises concern for growth in health disparities and increases in adverse health outcomes.
Fixations in the visual world paradigm: where, when, why?

Over the last 25 years, the visual world paradigm has enabled discoveries and theoretical advances in spoken language processing. However, the intuitive interpretation of fixations in the visual world paradigm—that fixations directly reflect over-time processes of activation and competition governing cognitive and language processing—deserves scrutiny. This paper provides a selective review of studies that suggest that the relations between fixations and ongoing processing are more complex than suggested by the intuitive interpretation. A particular challenge is explaining why context sometimes appears to have deep effects on language processing, while other times fixations appear to violate strong contextual constraints. I discuss implications of these seemingly contradictory patterns for theories of real-world language processing, and practical implications for using the visual world paradigm. Along the way, I review four possible linking hypotheses for connecting measures in the paradigm to theories of language and cognition. This review leads to the conclusion that implemented computational models will be needed to assess to what degree different linking hypotheses generate distinguishable predictions.
Hospital adoption of multiple health information exchange approaches and information accessibility.

OBJECTIVE Hospital engagement in electronic health information exchange (HIE) has increased over recent years. We aimed to 1) determine the change in adoption of 3 types of information exchange: secure messaging, provider portals, and use of an HIE; and 2) to assess if growth in each approach corresponded to increased ability to access and integrate patient information from outside providers. METHODS Panel analysis of all nonfederal, acute care hospitals in the United States using hospital- and year-fixed effects. The sample consisted of 1917 hospitals that responded to the American Hospital Association Information Technology Supplement every year from 2014 to 2016. RESULTS Adoption of each approach increased by 9-15 percentage points over the study period. The average number of HIE approaches used by each hospital increased from 1.0 to 1.4. Adoption of each approach was associated with increased likelihood that providers routinely had necessary outside information of 4.2-12.7 percentage points and 4.5-13.3 percentage points increase in information integration. Secure messaging was associated with the largest increase in both. Adoption of 1 approach increased the likelihood of having outside information by 10.3 percentage points, while adopting a second approach further increased the likelihood by 9.5 percentage points. Trends in number of approaches and integration were similar. DISCUSSION/CONCLUSION No single HIE tool provided high levels of usable, integrated health information. Instead, hospitals benefited from adopting multiple tools. Policy initiatives that reduce the complexity of enabling high value HIE could result in broader adoption of HIE and use of information to inform care.
Chapter 16 – The Theory and Measurement of Tax Incidence

The literature on tax incidence is so voluminous that a single chapter on tax incidence has to be highly selective. Chapter 16 focuses on three main issues. After reviewing the standard partial equilibrium analysis of tax incidence, the chapter begins with a discussion of the thorny issues related to measuring tax incidence in a general equilibrium setting, including the question of what the government does with the tax revenues. The chapter then turns to the equivalence of general taxes in a profitless, competitive, static economy. The chapter concludes with a detailed presentation of Harberger's seminal analysis of the incidence of the corporation income tax, ending with brief discussions of extensions to the Harberger model that affect the incidence of the tax. These include such things as variable factor supplies, market power, heterogeneous consumers, and long-run dynamic models.
African Studies: Geography

This entry briefly highlights the content of geographic work on Africa during the past three decades. Most geographic work in the 1970s and 1980s concentrated on regional geography with an emphasis on country surveys, descriptions and compilation of geographic data at country or regional level. The late 1980s and 1990s saw the rise of new paradigms in the study of African geography. While the empirical subject matter may be agriculture, health, gender issues, development, etc., the theoretical paradigm guiding geographic research during the 1990s was often about issues such as representation, discourse, resistance, and indigenous development within broader frameworks influenced by the ideas of prominent social science scholars such as Foucault, Said, and Sen. The works fall into the two main subdisciplines of geography, namely, human geography (by far the most dominant) and physical geography now commonly referred to as earth systems science and/or global change studies. Within these two main sub-disciplines, various theoretical perspectives overlap to characterize the growing body of research by geographers on Africa.