cssi/SciSciGPT-SciSciNet huggingface dataset:
Probability on Trees and Networks

Starting around the late 1950s, several research communities began relating the geometry of graphs to stochastic processes on these graphs. This book, twenty years in the making, ties together research in the field, encompassing work on percolation, isoperimetric inequalities, eigenvalues, transition probabilities, and random walks. Written by two leading researchers, the text emphasizes intuition, while giving complete proofs and more than 850 exercises. Many recent developments, in which the authors have played a leading role, are discussed, including percolation on trees and Cayley graphs, uniform spanning forests, the mass-transport technique, and connections on random walks on graphs to embedding in Hilbert space. This state-of-the-art account of probability on networks will be indispensable for graduate students and researchers alike.
Self-Control Group Therapy of Depression

The purpose of this chapter is to describe in some detail a self-control therapy program for depression. To this end we will provide the rationale and context for the development of the treatment program. Second, we will discuss briefly the model of depression on which the treatment program is based. Third, will be a description of subject/client characteristics. Fourth, the nature of the research support for the effectiveness of this program will be indicated. Finally, we will describe on a session-by-session basis the elements of the treatment program.
A job with a view: perspectives from the corporate side of the hospital

A change in job responsibilities from library manager to hospital administrator provides this year's Doe lecturer the opportunity to reflect on the values of the library profession from a fresh perspective. Librarians play a unique role and remain vital to the health care enterprise but are frequently misunderstood. Their role can be viewed from three angles: service, technology, and a unique sort of professionalism. Librarians must focus their service priorities on the needs of the institution, while remaining true to their own unique professional values. They must be advocates for the appropriate use of technology in support of those service roles. The passion that many librarians bring to their jobs makes librarianship a vocation as much as a profession. The mission and vision developed by the American Society of Health-System Pharmacists in 2001 provides a useful model for defining a personal professional mission and vision.
False Positives and Transparency

This paper develops a model of costly information acquisition, focusing on an application to scientific research. When research protocols are not fully transparent, scientists are incentivized to make their experiments more susceptible to false positives, despite their preference for better information. On the other hand, non-transparency can induce a well-intentioned scientist to undertake a costlier but more informative experiment if it also enables her to commit to acting scrupulously. Our analysis suggests, counterintuitively, that policies establishing greater transparency in scientific methodology might therefore ultimately lead to some scientists undertaking research that is worse for those interested in the results.
Malignant seeding of the biopsy needle tract outside of the radiation therapy field in a patient with Glioblastoma.

A 44-year-old male initially presented with a right thalamic brain tumor that was confirmed with stereotactic biopsy to be glioblastoma (GBM). The patient was treated with radiotherapy and temozolo...
Investigating global gene expression changes in a murine model of cherubism

Cherubism is a rare genetic disorder caused primarily by mutations in SH3BP2 resulting in excessive bone resorption and fibrous tissue overgrowth in the lower portions of the face. Bone marrow derived cell cultures derived from a murine model of cherubism display poor osteogenesis and spontaneous osteoclast formation. To develop a deeper understanding for the potential underlying mechanisms contributing to these phenotypes in mice, we compared global gene expression changes in hematopoietic and mesenchymal cell populations between cherubism and wild type mice. In the hematopoietic population, not surprisingly, upregulated genes were significantly enriched for functions related to osteoclastogenesis. However, these upregulated genes were also significantly enriched for functions associated with inflammation including arachidonic acid/prostaglandin signaling, regulators of coagulation and autoinflammation, extracellular matrix remodeling, and chemokine expression. In the mesenchymal population, we observed down regulation of osteoblast and adventitial reticular cell marker genes. Regulators of BMP and Wnt pathway associated genes showed numerous changes in gene expression, likely implicating the down regulation of BMP signaling and possibly the activation of certain Wnt pathways. Analyses of the cherubism derived mesenchymal population also revealed interesting changes in gene expression related to inflammation including the expression of distinct granzymes, chemokines, and sulfotransferases. These studies reveal complex changes in gene expression elicited from a cherubic mutation in Sh3bp2 that are informative to the mechanisms responding to inflammatory stimuli and repressing osteogenesis. The outcomes of this work are likely to have relevance not only to cherubism, but other inflammatory conditions impacting the skeleton.
The interferon-inducible protein TDRD7 inhibits AMP-activated protein kinase and thereby restricts autophagy-independent virus replication

The interferon system is the first line of defense against virus infection. Recently, using a high-throughput genetic screen of a human interferon-stimulated gene short-hairpin RNA library, we identified a viral restriction factor, TDRD7 (Tudor domain–containing 7). TDRD7 inhibits the paramyxo-/pneumoviruses (e.g. Sendai virus and respiratory syncytial virus) by interfering with the virus-induced cellular autophagy pathway, which these viruses use for their replication. Here, we report that TDRD7 is a viral restriction factor against herpes simplex virus (HSV-1). Using knockdown, knockout, and ectopic expression systems, we demonstrate the anti–HSV-1 activity of TDRD7 in multiple human and mouse cell types. TDRD7 inhibited the virus-activated AMP-activated protein kinase (AMPK), which was essential for HSV-1 replication. Genetic ablation or chemical inhibition of AMPK activity suppressed HSV-1 replication in multiple human and mouse cells. Mechanistically, HSV-1 replication after viral entry depended on AMPK but not on its function in autophagy. The antiviral activity of TDRD7 depended on its ability to inhibit virus-activated AMPK. In summary, our results indicate that the newly identified viral restriction factor TDRD7 inhibits AMPK and thereby blocks HSV-1 replication independently of the autophagy pathway. These findings suggest that AMPK inhibition represents a potential strategy to manage HSV-1 infections.
13 – Thermoplastic Elastomers

Publisher Summary This chapter presents details on morphology, properties, thermodynamic properties, rheology, and processing of thermoplastic elastomers (TPEs). A TPE will generally have the modulus versus temperature curve. All TPEs have certain similar structural characteristics and the most obvious is the presence of dissimilar components on a single macromolecular chain. The driving force for phase separation is usually enthalpic and generally one to two orders of magnitude weaker than primary valence bonds. Crystallinity, hydrogen bonding, and ionic and van der Waals driving forces all have been shown to cause micro phase separation in these systems. The terminal styrene segments reside in glassy micro domains which reinforce the elastomeric diene phase. The ethylene–propylene TPEs are distinguished from the cross-linked analogs that are not thermoplastics as re-forming is impossible. Polyurethane elastomers are segmented copolymers with an aromatic ring containing a hard segment and a polyether or polyester oligomer soft segment.
Applying systems and complexity science to real patient care.

Aims and objectives To describe the application of systems and complexity science principles to real patient care. Rationale Our current global health care system is not sustainable. It is structured based on the principles of reductionist science, which was discovered and developed over the past 400 to 600 years. Because of increasing pace of change and increasing complexity in our world, we have increased fragmentation in our health care system leading to more harm and waste. Over 100 years ago, the principles of systems, or complexity, science were discovered, first in the discipline of physics. These principles accommodate the constant change and biologic variability in our world. While reductionist principles would be applicable in a static, mechanical world where parts of the system could be isolated, this does not exist in the real biologic world. Methods For the past decade, our abdominal wall hernia team has been applying the principles of systems science to real patient care. Some of the tools we have applied include continuous quality improvement for whole hernia patient processes and non-linear analytical tools to gain insight to improve value-based outcomes. Until we learn to apply and scale these principles across our whole global health care system, we will continue to suffer the consequences of our current unsustainable system. Results We have learned that the application of systems and complexity science to real patient care can lead to lower costs and better outcomes in the context of patients with complex hernia problems. However, these concepts have not yet been adopted in our global health care system. Conclusion Applying the principles of systems and complexity science to our global health care system has the potential to lower costs and improve patient outcomes for any patient care process to which it is applied.
Anomalous refraction of optical spacetime wave packets

Refraction at the interface between two materials is fundamental to the interaction of light with photonic devices and to the propagation of light through the atmosphere at large1. Underpinning the traditional rules for the refraction of an optical field is the tacit presumption of the separability of its spatial and temporal degrees of freedom. We show here that endowing a pulsed beam with precise spatiotemporal spectral correlations2–4 unveils remarkable refractory phenomena, such as group-velocity invariance with respect to the refractive index, group-delay cancellation, anomalous group-velocity increase in higher-index materials, and tunable group velocity by varying the angle of incidence. A law of refraction for ‘spacetime’ (ST) wave packets5–10 encompassing these effects is verified experimentally in a variety of optical materials. Spacetime refraction defies our expectations derived from Fermat’s principle and offers new opportunities for moulding the flow of light and other wave phenomena. An appropriately designed pulsed beam crossing an interface is shown to enable phenomena including anomalous group-velocity increase in higher-index materials, and tunable group velocity by varying the angle of incidence.
Physician Employment Status: Collective Bargaining and Strikes

Throughout medical history, physicians have rarely formed unions and/or carried out strikes. Today, the medical profession worldwide seems in a heightened state of discontent, but their chosen directions to fight back over their conditions of labor appear blurry and ineffective. With the continual increase in corporatization schemes, physicians continue to be drawn into the role of employee of ever-larger organizations which leave the independent physician-run practice behind; it has become financially more and more difficult to maintain a practice while procuring sufficient reimbursement from insurance companies and patients. As a result, they are not able to maintain their professional independence, which would allow them to act as their patient’s agent in determining what would be done and where it would be done. Because they now have to obey the corporate mandate of revenue enhancement and cost cutting, they no longer have free rein to do as they wish in their professional practice. This condition may impair patient well-being and may surely affect the larger public health.
Group incentive compatibility in the housing market problem with weak preferences

Abstract I consider the housing market problem with weak preferences. In this context, I provide a sufficient condition for weak group strategy proofness; no group of agents can jointly misreport their preferences such that each agent in the group becomes better-off. Using this sufficient condition, I prove that the top trading absorbing sets, top cycles, and highest priority object rules satisfy weak group strategy proofness. Thus, this paper establishes that it is possible to achieve weak group strategy proofness, along with other desirable results, for the housing market problem with weak preferences even though group strategy proofness is incompatible with Pareto efficiency in this setting.
Repitencia escolar: análisis y reflexiones en un establecimiento educacional en la comuna de Valparaíso, Chile

The School repetition is a multidimensional phenomenon and one of the three critical knots that education presents for the fulfillment of its universalization. With the purpose of identifying associated risk factors in an educational establishment in the commune of Valparaiso, a mixed investigation is carried out where primary and secondary sources of information are analyzed and described by means of frequency analysis, correlations, contingency tables and linear regression on a data base of 866 students, besides content analysis of semistructured interviews to six teachers. The results establish that the risk of repetition is due to socio-demographic, academic and socio-emotional factors, from which it is concluded that it is necessary to work on three components: family support, academic accompaniment and promotion of school coexistence.
What Does the History of Technology Regulation Teach Us About Nano Oversight

As policymakers struggle to develop regulatory oversight models for nanotechnologies, there are important lessons that can be drawn from previous attempts to govern other emerging technologies. Five such lessons are: (1) public confidence and trust in a technology and its regulatory oversight is probably the most important factor for the commercial success of a technology; (2) regulation should avoid discriminating against particular technologies unless there is a scientifically-based rationale for the disparate treatment; (3) regulatory systems need to be flexible and adaptive to rapidly changing technologies; (4) ethical and social concerns of the public about emerging technologies need to be expressly acknowledged and addressed in regulatory oversight; and (5) international harmonization of regulation may be beneficial in a rapidly globalizing world.
CRC-Based Error Detection Constructions for FLT and ITA Finite Field Inversions Over GF(2 m )

Binary extension finite fields ${\mathrm{ GF}}(2^{m})$ have received prominent attention in the literature due to their application in many modern public-key cryptosystems and error-correcting codes. In particular, the inversion over ${\mathrm{ GF}}(2^{m})$ is crucial for current and postquantum cryptographic applications. Schemes such as Fermat’s little theorem (FLT) and the Itoh–Tsujii algorithm (ITA) have been studied to achieve better performance; however, this arithmetic operation is a complex, expensive, and time-consuming task that may require thousands of gates, increasing its vulnerability chance to natural defects. In this work, we propose efficient hardware architectures based on cyclic redundancy check (CRC) as error detection schemes for state-of-the-art finite field inversion over ${\mathrm{ GF}}(2^{m})$ for a polynomial basis. To verify the derivations of the formulations, software implementations are performed. Likewise, hardware implementations of the original finite field inversions with the proposed error detection schemes are performed over Xilinx field-programmable gate array (FPGA) verifying that the proposed schemes achieve high error coverage with acceptable overhead.
Coronavirus disease 2019 infection and hypertensive disorders of pregnancy.

Objective The possible connection between COVID-19 and hypertensive disorders of pregnancy (HDP) remains unclear (1). Elucidating these outcomes is important both to better understand COVID-19 pathophysiology and to improve patient care in pregnant patients with COVID-19. Our objectives were to test the hypothesis that COVID-19 infection is associated with an increased risk of HDP and to examine the association between the gestational age at COVID-19 infection and delivery and HDP risk. Study Design This was a retrospective cohort study at Barnes-Jewish Hospital in St. Louis, which has a universal COVID-19 testing policy on admission to labor and delivery. All women admitted for delivery from June 1, 2020-November 30, 2020, with a positive Sars-CoV-2 test at any time during pregnancy were compared 1:2 with randomly selected controls who had a negative SARS-CoV-2 test and were matched for race and parity. COVID-19 was diagnosed with nasopharyngeal RT-PCR or rapid antigen testing. HDP was diagnosed using standard criteria. Cox proportional hazards models with left truncation to account for the varying gestational age at COVID-19 diagnosis, and random effects (frailty) to account for the matching design and small cluster sizes, were used to examine the association between COVID-19 and HDP (2). As a sensitivity analysis we also examined early (before 32 weeks gestation) vs. late COVID-19 infection and HDP development. The study was deemed exempt from review by the Institutional Review Board. Results Of 1856 births, there were 83 women (4.5%) with COVID-19 infection. There was no significant difference in baseline characteristics between COVID-19 infected women and controls. Patients with COVID-19 infection had almost a two-fold risk of HDP (HR 1.93 (95%CI 1.13, 3.31). However, COVID-19 infection was not associated with severity of HDP, and severity of COVID-19 (3) was not associated with HDP development. Among patients with COVID-19 and HDP at delivery, the median interval from COVID-19 diagnosis to delivery was 3.8 weeks (IQR 0.29, 11.5). In additional analysis, early, but not late, COVID-19 infection was associated with HDP development (HR for early COVID-19 2.17 (95%CI 1.11, 4.24), HR for late COVID-19 1.68, (95%CI 0.79, 3.57). Conclusions Early COVID-19 infections are associated with HDP, even when accounting for differential exposure and delivery times, suggesting that COVID-19 infection may alter pregnancy physiology and increase the risk of HDP development over time. Infection closer to term is not associated with HDP, which likely reflects our high proportion of asymptomatic infections found at the time of delivery from a universal testing policy (4) and insufficient time to develop HDP in these cases. Furthermore, emerging evidence suggests that COVID-19 modulates placental ACE2 expression, which may be related to HDP development (5). Our study is limited by sampling in a single institution with a high HDP incidence. However, our results suggest that monitoring of patients with antepartum COVID-19 infection should encompass precautions for HDP development.
Impact of elevated troponins on mortality of ICU patients

Introduction: Myocardial injury as evidenced by elevated cardiac troponin levels may occur in 7-36% of hospitalized patients with coronavirus 2019 (COVID-19). Studies have shown that COVID-19 patients with elevated cardiac troponin are more likely to require the intensive care unit (ICU) and mechanical ventilation and have a higher risk of death. However, studies on the impact of elevated troponins at the time of hospital admission on mortality of ICU patients are limited. Here we aim to characterize, compare, and analyze COVID-19 patients in our institution's ICUs who had elevated troponins. Methods:This study is a retrospective analysis of adult patients with COVID-19 admitted to the ICUs of a tertiary care hospital between 03/01/2020 and 05/31/2020. Myocardial injury was defined as troponin ≥ 0.04 ng/mL. Only patients who had troponins measured within 24 hours of hospital admission were included. We excluded patients with a past medical history of chronic kidney disease (CKD) or end-stage renal disease (ESRD). We also excluded those patients who were transferred to our ICU from another hospital and where admission labs from the transferring institution were not available for our review. We compared the clinical characteristics and outcomes of critically ill COVID-19 patients who had elevated troponins with those who did not.Results: Of the 210 patients admitted with COVID-related Acute Respiratory Distress Syndrome, 178 had troponin measured within 24 hours of hospital admission. 25 patients had a past medical history of CKD or ESRD and 11 patients were transferred from another hospital with no labs available from their day of admission. Of the 142 remaining patients, 72 (50.7%) had an elevated troponin while 70 (49.9%) had a normal troponin at presentation. Patients with elevated troponins were older (67.5 ± 15.1 vs 60.2 ± 14.2), and predominantly male (72.2% vs. 54.3%). Inflammatory markers were significantly elevated in both groups but not statistically different. Therapies provided were similar in both groups. Most importantly, patients with an elevated troponin had significantly increased risk of mortality compared to those with a normal troponin at admission (55.6% vs. 34.3%).Conclusion: Our results suggest that myocardial injury is a common occurrence in COVID-19 patients requiring ICU admission. Additionally, mortality in this population is significantly higher further indicating myocardial injury as a predictor of mortality. To determine if elevated troponin levels are independent of other risk factors for mortality in COVID-19 such as age, and gender will need to be determined in future studies.
Bacterial protein toxins as biological weapons

The use of biological agents as an instrument of terror and warfare has been well documented. The appeal of biowarfare agents is attributed to their potential to kill or incapacitate exposed victims, availability, inexpensive production cost, low visibility, and relative ease of delivery. Advances in science and technology can also contribute to the development of novel and more deleterious agents and the proliferation of potential bioweapons that have regional and global security associations. This chapter focuses on three bacterial protein toxins that are included in the Centers for Disease Control and Prevention (CDC) select agents and toxins list: botulinum neurotoxin (BoNT), a Category A agent; staphylococcal enterotoxin, a Category B agent; and epsilon toxin from Clostridium perfringens, a Category B agent; and examines their potential as biological weapons. The beginnings of U.S. bioterrorism awareness and preventive and protective strategies, including the regulatory measures adapted by the federal government to thwart and palliate biological warfare (BW) threats, are also discussed.
The Ins and Outs of Gas Flows in Elliptical Galaxies

Because of their deep potential wells elliptical galaxies provide an ideal venue to investigate the longterm exchanges of matter between gas and stars, a question of fundamental astronomical interest. Although star formation during the early history of elliptical galaxies was rapid and efficient, the metal abundance and its gradient in these galaxies indicates a multistage, dissipative, and rather complex initial transformation of gas into stars. During or following the initial conversion into stars, a massive gaseous outflow must have occurred. This is indicated by the large amount of iron-rich gas in elliptical-rich clusters, often exceeding the entire baryonic mass of all stellar matter within the cluster galaxies. This ejection was evidently driven by the large supernova rate in young stellar populations.
Conservative Management of Urinary Retention in Women

Women with UR can present in acute or chronic status. A careful history and physical examination will lead clinicians to the possible cause of the UR and, thereby, the appropriate management. In selected cases, use of UDS and cystourethroscopy will help to distinguish cases of UR with a bladder etiology from those of outlet/urethral obstruction.
Challenges and opportunities in advancing models of care for older adults: an assessment of the National Institute on Aging research portfolio.

OBJECTIVES: To identify existing projects supported by the National Institute on Aging (NIA) that may relate to the recommendations for models of care (MOCs) presented in the 2008 Institute of Medicine Report, Retooling for an Aging America: Building the Healthcare Workforce. DESIGN: Cross-sectional analysis of NIA's grant portfolio. SETTING: NIA. PARTICIPANTS: NIA grantees. MEASUREMENTS: NIA's grant portfolio was queried for the period 1999 to 2008 using a variety of search terms related to MOCs. Inclusion criteria were adherence to guiding principles for MOCs (comprehensive care, efficient care, older person as an active partner) or focus on innovative feature(s) of MOCs (interdisciplinary care, care management, chronic disease self-management, pharmaceutical management, preventive home visits, proactive rehabilitation, transitional care). Exclusion criteria were lack of focus on an intervention and focus on informal caregivers. Expert NIA staff reviewed and validated projects. RESULTS: One hundred thirty-five grants were identified. These grants represent fewer than 1% of the approximate number of grants NIA has funded over this same period of time (?24,000 grants). Forty-four percent focused on components of comprehensive care and 34% on active involvement of older adults. Approximately half specifically focused on innovative features of MOCs, ranging from chronic disease self-management (32%) and proactive rehabilitation (26%) to preventive home visits (1%) and transitional care (1%). The majority of projects were investigator-initiated grants (46%). CONCLUSION: NIA has supported the development of many interventions that include components of MOCs related to recommendations from the IOM report. The challenge for the future will be determining which of the many components of comprehensive care systems are most effective for which subsets of the elderly population and assessing opportunities for enhanced collaboration between public and private aging research stakeholders.
Exchange-Rate-based Stabilisation, Durables Consumption and the Stylised Facts*

In this article we show that a model featuring durable consumer goods, imperfect substitution between domestic and foreign assets, and weak credibility can explain the qualitative and quantitative aspects of the stylised facts associated with exchange-rate-based stabilisation, including the tremendous increase in real interest rates. Following a temporary reduction in the crawl, total consumption spending rises 14–26%, the real exchange rate appreciates 20–37% and the current account deficit swells to 10–15% of gross domestic product. Despite large capital inflows, the real interest rate increases from 10 to 20–100%.
Intersectionality and the Development of Self and Identity

Intersectionality is a key theoretical, empirical, and applied construct in the social sciences and the humanities. In this essay, we review the origins of the construct and the foundational theory and research that served to cement its importance in these fields. We then present a brief overview of how intersectionality guides current theory, research, and social policy in education, feminist studies, politics, psychology, and sociology, concluding with a discussion of the key issues that need to be addressed for this construct to deliver in its promise to strengthen theory, research, and practice in the social sciences. Keywords: identity; self; intersectionality; power; inequality; gender; race; culture
Is the Euro Zone an Optimal Currency Area

The aim of this paper is to assess whether the Euro zone is an optimal currency area. The judgement is made on the basis of the existing literature and available data for several criteria as a part of the OCA Theory. The ultimate conclusion is that the Euro zone is not an optimal currency area, albeit significant advancements towards it were made past the introduction of the euro, in terms of inflation convergence, financial integration and intra-trade intensification. Yet, the criteria of labour mobility, wage flexibility, fiscal and political integration are far from being satisfied.
Electron spin grating in multiple quantum well semiconductors

Summary form only given. We report a new type of optically induced, transient diffraction grating in a multiple quantum well (MQW) semiconductor. The grating is formed by the spatial modulation of the electron spin orientation within a uniform excess carrier distribution and allows the measurement of the in-well electron mobility. We present four-wave mixing results for spin-gratings in a GaAs/AlGaAs MQW semiconductor using picosecond laser pulses and compare the diffusion coefficients determined from spin and amplitude gratings.
Why Did the U.N. Security Council Support the Anglo-American Project to Transform Postwar Iraq? The Evolution of International Law in the Shadow of the American Hegemon

This article examines why the U.N. Security Council supported the Anglo-American project to transform Iraq, even though the international law of occupation prohibits this type of project. It is divided into four sections. Section one presents the article's framework of analysis, which is based on Detlev Vagt's (2001) conceptualization of hegemonic international law and Jose Alvarez's (2003) recent application of this concept to recent debates in international law. The second section assesses the impact American hegemony has had on international law in the post-Cold War era, arguing that American neo-liberal values and its idealized vision of intrastate order have influenced international institutions' strategies. The third section studies the UN's postwar mission in Kosovo. It not only shows how this is an example of American hegemonic international law, but it helps explain why the Security Council may have been compelled to support the Anglo-American project to transform Iraq. The last section considers the debate regarding the United Kingdom and the United States' request for a resolution legitimating its occupation of Iraq. It demonstrates that Resolution 1483 met most of the occupying powers' demands, confirming that it was an outcome of American hegemonic international law.
ESR studies of donor clusters in silicon

Abstract ESR spectra for Si:P and Si:As samples with donor concentrations ranging from 9×1016 to 5×1017/cc have been obtaines in the range 4.2K to 20K at 9 GHz. dχ″ dH spectra were integrated to obtain χ″(N,T,H) allowing the determination of relative contributions from different size clusters. The ratio of integrated intensity of the outer lines to the total integrated intensity obeys Poisson statistics and yields a characteristic volume Vc for Si:P of 8.21×106A3. A search outside the isolated donor hyperfine lines has revealed no extra transitions 0.03% of the outer hyperfine lines. A new many-electron cluster hyperfine interaction is formulated which takes account of topological disorder for larger clusters. The effect of hyperfine topological broadening and cluster-cluster interactions on the ESR line widths and shapes are considered.
Early hominid hunting and scavenging: the role of meat as an energy source

Abstract Perspectives have shifted recently from the traditional view that early hominids were hunters to one which now sees them as opportunistic scavengers. However, both views share the common underlying nutritional assumption that meat inevitably provides a “high quality” food that will be incorporated into human diet more or less to the extent that animals are avaible and accessible. This paper argues that meat may actually have been a relatively marginal source of sustenance for early hominids, because physiological limits to total protein intake (plant and animal), scarcity of fat in most African ungulates, comparatively high levels of protein in many plant foods, and the inability of early hominids to extract lipids from the cancellous tissue of bones, acted together to maintain their total meat intakes at modest levels, particularly during seasonal or inter-annual periods of resource stress.
Structure and recognition of sheared tandem G x A base pairs associated with human centromere DNA sequence at atomic resolution.

G x A mismatched base pairs are frequently found in nucleic acids. Human centromere DNA sequences contain unusual repeating motifs, e.g. , (GAATG)n x (CATTC)n found in the human chromosome. The purine-rich strand of this repeating pentamer sequence forms duplex and hairpin structures with unusual stability. The high stability of these structures is contributed by the "sheared" G x A base pairs which present a novel recognition surface for ligands and proteins. We have solved the crystal structure, by the multiple-wavelength anomalous diffraction (MAD) method of d(CCGAATGAGG) in which the centromere core sequence motif GAATG is embedded. Three crystal forms were refined to near-atomic resolution. The structures reveal the detailed conformation of tandem G x A base pairs whose unique hydrogen-bonding surface has interesting interactions with bases, hydrated magnesium ions, cobalt(III)hexaammine, spermine, and water molecules. The results are relevant in understanding the structure associated with human centromere sequence in particular and G x A base pairs in nucleic acids (including RNA, like ribozyme) in general.
Temperature-programmed desorption (TPD), reaction (TPR) and oxidation (TPO) of species formed on Rh/MgO after interaction with H2 and CO

Abstract Chemisorption and reaction of CO on a 2.5 wt. % Rh/MgO catalyst appears to be sensitive to the adsorption temperature and the extent of CO/He treatment. CO, CO 2 and H 2 are produced during temperature-programmed desorption following CO chemisorption. Results from 13 CO experiments suggest that most CO 2 arises from interaction of CO residing on Rh with -OH groups on the magnesia support, and also from direct interaction of CO with the support. Inactive carbon accumulates on the Rh surface during CO/He treatment at 573 K. This can only partly be removed by H 2 or O 2 treatments at 723 K, and is considered to be partly responsible for deactivation of the catalyst and suppression of H 2 and CO chemisorption after prolonged treatment of the catalyst with CO/He. Hydrogen chemisorption on the present Rh/MgO catalyst is found to be an activated process. The results suggest that this activated chemisorbed H 2 is present on the Rh and not on the support.
An oscillator model representative of electron interactions with EMIC waves

Nonlinear interactions of relativistic electrons with a monochromatic electromagnetic ion cyclotron (EMIC) wave were investigated in previous studies by solving the Lorentz equation for test particles. In the present study, we simplify the Lorentz equation to a set of oscillator equations, which capture the key features of the wave-particle interaction. These reduced oscillator equations confirm that the inhomogeneity ratio plays an important role in determining the nonlinear nature of the interaction with a monochromatic wave. When considering the case of two discrete wave elements, three general regimes were identified in the nonlinear interactions, depending on the separation of the two wave numbers: There were (1) a decoupled regime in which electrons pass only one of the two distant resonance points, (2) a coupled regime in which electrons pass both of the two moderately separated resonance points, and (3) a degenerate regime in which electrons pass two closely situated resonance points. The decoupled and degenerate regimes in the nonlinear interaction are characterized by phase bunching. However, the electrons experience alternate trapping and detrapping near the separatrix in the coupled regime, leading to chaotic nature of electrons' motion. The linear interaction region is also considered, where the linear superposition principle is tested. The linear approximation results generally agree with the two-wave simulation except in the coupled regime.
Analyzing Optional Test Items

Traditional item analysis and reliability estimation procedures cannot be used in evaluating the effectiveness of a test consisting in whole or in part of optional items. This paper considers alternative methods for determining the difficulty, discrimination, and reliability of optional items on essay and other types of tests. Although not so precise as traditional procedures, these approaches can yield useful information for assessing the functioning of optional items and item composites. A computer program, available in BASICA and FORTRAN, has been written to compute the measures described in this paper. In addition, illustrative analysis of two tests with optional items are provided.
Phenomenological characteristics of attentional biases towards threat: A critical review.

Although research has consistently revealed the presence of a general attentional bias towards threat, empirical and theoretical ambiguity exists in determining whether attentional biases are comprised of facilitated attention to threat, difficulty in disengagement from threat, or both, as well as whether attentional biases reflect automatic or strategic processes. This paper reviews empirical investigations across four common assessment tasks: the Stroop (masked and unmasked), dot probe, visual search, and the Posner tasks. Although the review finds inconsistencies both within and between assessment tasks, the evidence suggests that attentional biases towards threat are comprised of each of the phenomenological characteristics addressed in this paper. Contemporary theoretical models of attentional biases in anxiety are summarized and critically reviewed in light of the current evidence. Suggestions for future research are addressed, including a need to investigate the psychometric properties of the assessment tasks, to utilize consistent theoretically driven operationalizations of attentional biases, and to provide a temporal description of the characteristics of attentional biases towards threat.
Effect of adaptation level on maintained firing and sensitivity in receptive field center of X and Y cells.

Maintained firing rates of X cells and Y cells were compared at 6 adaptation levels (AL) between −2.71 log cd/m2 and 2.28 log cd/m2 (10 mm2 pupil size). X cell maintained firing was higher at all ALs and was statistically different at medium and high ones. Changes in AL had nearly identical effects upon X and Y cell suprathreshold sensitivity to a flashing spot in the center of their receptive fields; the Weber function had a slope of 0.744 for Y cells and 0.743 for X cells. These values are not statistically different.
The Substance of Trust Between Teachers and Principals

Can you define trust? Vague responses to this question prompted the authors to undertake a study to determine how teachers view trust. Their results, while reducing some of the ambiguity attached to the word, indicate that more research is required.
Aircraft Noise: A Potential Health Hazard

A questionnaire distributed to two groups, one living within the flight pattern of a major airport and the other in a nonflight area, sought to determine whether these groups would respond differen...
Chaotic flows in a universe with a negative quantum pressure

Lockhart, Misra, and Prigogine have pointed out that geodesic flow in an open k = -1 Friedmann universe is unstable. The implications of this instability are considered for a universe whose energetics was dominated, at some early time, by the Lorentz-invariant expectation value of a quantum stress-energy tensor.
An investigation of the tellurium-rich uranium tellurides using X-ray powder diffraction

Abstract A comprehensive X-ray powder diffraction study of synthesized uranium telluride phases produced new and improved diffraction pattern data compared to published values. Experimental work at the tellurium-rich end of the U-Te phase diagram, using a high intensity rotating anode diffraction system, has yielded data for the phases UTe 2 , U 2 Te 5 , UTe 3 , UTe 3.4 and UTe 5 . Indexing of this experimental diffraction data has produced more complete patterns for the previously published phases UTe 2 , UTe 3 and UTe 5 . The first conclusive experimental diffractometer data are presented proving the existence of the phase U 2 Te 5 . The phase UTe 3.4 is structurally very similar to a reported β-UTe 3 , but is considered to be a new phase based on its composition and computer indexing.
The use of moment theory to interpret diffusion and sieving measurements in terms of the pore size distribution in heteroporous membranes

Moment theory has been applied to model porous membranes to show that one can place reasonable bounds on the cumulative pore size distribution, the hindered diffusivity or the reflection coefficient of large solutes in a heteroporous membrane by measuring the diffusive permeability to a small solute, the hydraulic permeability and one or two additional transport characteristics. These additional measurements involve either the flux of a small solute at Pe∼1, the hindered diffusivity of a large solute or the reflection coefficient of a large solute at Pea1. Membrane heteroporosity is incroporated in the predicted bounds without requiring one to make any a priori assumptions about the nature of the pore size distribution. In this paper, the results from calculations performed with different model membranes containing log-normal pore size distributions are reported. A comparison of the results obtained with three different membranes shows that one can distinguish between membranes with the same average pore size but different pore size distributions by measuring either the hindered diffusion coefficient or the reflection coefficient of two different sized solutes. A comparison of the bounds on D and the bounds on σ predicted from different types of transport measurements shows that, under certain conditions, one can place tighter bounds on one transport characteristic by measuring a different one.
Biodegradation of linear alkylbenzenesulphonates (LAS) by mixed methanotrophic-heterotrophic cultures.

The biodegradation of undecylbenzenesulphonate (C 11 LAS) was studied in shake flasks at 21 o C using two mixed bacterial cultures. The first culture, MM1, contained a type II methanotroph and four heterotrophs, and was enriched from a groundwater aquifer. The second culture, MC, consisted of five heterotrophic strains, most of them belonging to the genus Pseudomonas, and was isolated from the wastewater of a detergent plant. Methane, carbon dioxide and oxygen concentrations were determined by gas chromatography. Concentrations of C 11 LAS and the aromatic intermediates were determined by reversed-phase HPLC. In spite of faster transformation of the alkyl side-chain by the culture MC, the culture MM1 containing type II methanotroph was capable of further degradation of C 11 LAS aromatic intermediates (sulphophenylalkanoates). The most probable mechanism for the degradation of the alkyl part of the C 11 LAS molecule by both cultures was ω-oxidation of the terminal methyl group followed by β-oxidation. Studies of methane utilization demonstrated an approximately three times higher second-order rate coefficient for methane consumption (k max /K s ) in the absence of C 11 LAS. This indicates a possible metabolic activity of methanotrophs in the transformation of the complex LAS molecule due to the methane monooxygenase enzyme system
Two problems in metric diophantine approximation, I

Abstract For an arbitrary sequence { α n } of nonnegative real numbers there is no known necessary and sufficient condition that for almost all x (in the sense of Lebesgue measure) there are infinitely many fractions p q satisfying |x − p q | α q q . With a restriction on { α n } weaker than any previously used, except in a recent result of Erdos, we solve this problem and the analogous problem where p and q are required to be relatively prime.
A tale of 2 (or more) tails: PECAM-1 regulation of GPIb-IX-V signaling

A defining characteristic of many blood cells is their ability to attach to the vessel wall from flowing blood. Of all blood cells, platelets are uniquely able to attach efficiently at shear stresses exceeding 10 dynes/cm[2][1], a property that reflects their preeminent role in stanching blood loss
Prosthodontic considerations for the transmandibular implant

Abstract The transmandibular implant has been designed to provide the patient with a severely atrophic mandible an implant that will bear the masticatory load. Thirteen edentulous patients treated with maxillary complete dentures and mandibular overdentures retained by the transmandibular implant were examined biannually for 2 years. Prosthodontic complications included the development of parafunctional habits, “combination syndrome”, and epulis in association with the mandibular denture. Surgery was necessary to control chronic mucosal irritation related to muscle pull in one patient. Among the soft tissue parameters, plaque index, gingival index, and sulcus depth demonstrated statistically significant correlations (Spearman). All patients reported an absence of discomfort and those with previous functional complaints reported the ability to masticate all foods. Patient response to overdenture reconstruction with the transmandibular implant seems to be similar to that observed with the combination case. Oral hygiene appears to be directly related to the soft tissue response.
Bilingual performance on nonword repetition in Spanish and English

Background: Nonword repetition (NWR) involves the ability to perceive, store, recall and reproduce phonological sequences. These same abilities play a role in word and morpheme learning. Cross-linguistic studies of performance on NWR tasks, word learning, and morpheme learning yield patterns of increased performance on all three tasks as a function of age and language experience. These results are consistent with the idea that there may be universal information-processing mechanisms supporting language learning. Because bilingual children's language experience is divided across two languages, studying performance in two languages on NWR could inform one's understanding of the relationship between information processing and language learning.Aims: The primary aims of this study were to compare bilingual language learners' recall of Spanish-like and English-like items on NWR tasks and to assess the relationships between performance on NWR, semantics, and morphology tasks.Methods & Procedures: Sixty-two Hisp...
Development of New S-N Curves Based on Small Crack Methodology

The propagation behavior of short cracks cannot be studied by linear elastic methods because of large plastic region near the crack tip, as well as a breakdown in correlation of the stress intensity factor with the fatigue crack growth rates. The proposed fatigue design approach incorporates a distance parameter in conjunction with linear elastic fracture mechanics and effectively integrates long and short crack growth test data. This distance parameter is a material constant that allows for the effects of (a) large-scale plasticity, (b) crack closure and (c) fatigue crack threshold. Furthermore, this parameter can be used to successfully predict fatigue crack growth behavior of short cracks. The practical application of this method to study fatigue crack initiation in pressure vessels rests on the concept that initiation occurs only when the material ahead of the crack tip is damaged enough by cyclic straining. The initiation and growth of small cracks have been investigated along with consideration for crack closure.Copyright © 2006 by ASME