cssi/SciSciGPT-SciSciNet huggingface dataset:
Charge-Transfer or Excimeric State? Exploring the Nature of The Excited State in Cofacially Arrayed Polyfluorene Derivatives

Abstract It is well known that upon electronic excitation various π-stacked dimers readily exhibit excimer formation, facilitated by a perfect sandwich-like arrangement between the chromophores. However, it is unclear whether such a dimer is also capable of electron transfer upon excitation, if a strong electron-donating group is covalently attached. In this work, we probe the nature of the excited state in a series of cofacially arrayed polyfluorene derivatives with electron-rich aromatic donor attached via a methylene linker. Our studies show that in all cases excimer formation is energetically favorable, and promotion of a charge-transfer state in such systems is possible but requires a free energy for electron transfer far exceeding 1 V. These findings shed light on important design principles for molecular scaffolds capable of stabilizing both excimeric and charge-transfer states upon their excitation.
Context and complexity in the clinical learning environment.

The learning environment is an inherently complex concept. It is situated at the intersection of learning and context and is fluid and multifaceted. Some of the complexity stems from the relativist...
Use of Skin and Soft Tissue Substitutes in Maxillofacial Reconstruction

Skin and soft tissue substitutes serve an important role in maxillofacial reconstructive surgery. This chapter informs the surgeon of the available dermal substitutes, indications for use, protocol for application, and characteristics of the ideal substitute and speculates on future developments. Selected common dermal substitutes are reviewed with clinical photos demonstrating the products in use.
(CH3NH3)AuX4⋅H2O (X=Cl, Br) and (CH3NH3)AuCl4: Low-Band Gap Lead-Free Layered Gold Halide Perovskite Materials

Perovskite solar cells have recently enabled power conversion efficiency comparable to established technologies such as silicon and cadmium telluride. Ongoing efforts to improve the stability of halide perovskites in ambient air has yielded promising results. However, the presence of toxic heavy element lead (Pb) remains a major concern requiring further attention. Herein, we report three new Pb-free hybrid organic-inorganic perovskite-type halides based on gold (Au), (CH3 NH3 )AuBr4 ⋅H2 O (1), (CH3 NH3 )AuCl4 ⋅H2 O (2), and (CH3 NH3 )AuCl4 (3). Hydrated compounds 1 and 2 crystallize in a brand-new structure type featuring perovskite-derived 2D layers and 1D chains based on pseudo-octahedral AuX6 building blocks. In contrast, the novel crystal structure of the solvent-free compound 3 shows an exotic non-perovskite quasi-2D layered structure containing edge- and corner-shared AuCl6 octahedra. The use of Au metal instead of Pb results in unprecedented low band gaps below 2.5 eV for single-layered metal chlorides and bromides. Moreover, at room temperature the three compounds show a weak blue emission due to the electronic transition between Au-6s and Au-5d, in agreement with the density function theory (DFT) calculation results. These findings are discussed in the context of viability of Au-based halides as alternatives for Pb-based halides for optoelectronic applications.
‘You get in a hole, it’s like quicksand’: a grounded theory analysis of social support amid materially bounded decision-making processes*

ABSTRACTFinancial precarity is a reality for a significant portion of the U.S. population. The inability of people to live sustainably has wide-ranging ramifications for individuals, families, comm...
Connectivity of the Gulf of Mexico Continental Shelf Fish Populations and Implications of Simulated Oil Spills

The Gulf of Mexico (GoM) marine ecosystem is experiencing acute stressors. Natural (e.g., hurricanes, harmful algal blooms) or anthropogenic (e.g., oil spills), these stressors have the potential to impact fish populations and decrease biodiversity that may be difficult to recover unless the ecosystem is resilient.
Outpatient telephonic transitional care after hospital discharge improves survival in cirrhotic patients.

Outpatient telephonic transitional care after hospital discharge improves survival in cirrhotic patients
Rapid correction of hyperkalemia is associated with reduced mortality in ED patients.

Abstract Background Hyperkalemia (HK) is common and associated with mortality. Our purpose was to determine if the rapid correction of elevated serum potassium level (K+) was associated with reduced mortality in emergency department (ED) patients. Methods Design: We reviewed the electronic medical records (EMR) of ED patients with HK (K+ ≥ 5.5 mEq/L) from 10/2016–10/2017. Setting: Large, academic ED. Participants: Adult ED patients presenting with hyperkalemia. Main outcomes and measures: The main outcome was in-hospital mortality. We compared outcomes of patients whose K+ normalized (dropped below 5.5 mEq/L) with those whose K+ did not normalize using chi-square and multivariate analyses to determine the associations between predictor variables and outcomes. Results From 114,977 ED visits, 1033 patients (0.9%, 95%CI 0.85–0.95%) had HK. Their mean (SD) age was 60 (26) years and 58% were male. Of these, 884 had a second K+ measured within a median (IQR) of 5 (3–8) hours. Mortality and admission rates were higher in patients with HK vs. those with normal K+ (8.5% vs. 0.8%, P Conclusions Normalization of K+ during the ED stay in patients with HK is associated with a 50% mortality reduction. Efforts to rapidly identify and treat HK in the ED are needed.
Metabolite Identification Using Artificial Neural Network

Metabolite identification is a major bottleneck in mass spectrometry-based metabolomic studies. In a typical untargeted metabolomic study that uses tandem MS (MS/MS), the identities of metabolites are determined by matching the experimental MS/MS data against those in spectral libraries. However, existing spectral libraries cover only a small fraction of known compounds. We introduce a neural network model to predict the identity of analytes whose reference measurements are not available in spectral libraries. Specifically, an artificial neural network model is trained to predict the fingerprints of compounds based on their experimental MS/MS spectra. Candidates are retrieved from metabolite databases based on molecular formula or precursor mass. The candidate with the most similar fingerprint is chosen as the predicted one. The method was evaluated via an independent dataset. The results show that our neural network model improves MS/MS-based metabolite identification accuracy by a considerable margin compared to previous computational methods, such as Metfrag and CSI:FingerID.
Antibacterial nanoparticles: On a mission to save your teeth

Few people realize that upon leaving the dentist’s office, their new filling, implant, or other dental restoration is already under attack by millions of oral bacteria.Soon, the bacteria form biofi...
Clostridioides difficile Senses and Hijacks Host Heme for Incorporation into an Oxidative Stress Defense System.

Summary Clostridioides difficile infection of the colon leads to severe inflammation and damage to the gastrointestinal epithelium due to the production of potent toxins. This inflammatory tissue damage causes the liberation of high concentrations of host heme at infection sites. Here, we identify the C. difficile heme-sensing membrane protein system (HsmRA) and show that this operon induces a protective response that repurposes heme to counteract antimicrobial oxidative stress responses. HsmR senses vertebrate heme, leading to increased expression of the hsmRA operon and subsequent deployment of HsmA to capture heme and reduce redox damage caused by inflammatory mediators of protection and antibiotic therapy. Strains with inactivated hsmR or hsmA have increased sensitivity to redox-active compounds and reduced colonization persistence in a murine model of relapse C. difficile infection. These results define a mechanism exploited by C. difficile to repurpose toxic heme within the inflamed gut as a shield against antimicrobial compounds.
Introduction to Focused Issue: History of Textiles and Fashion

The introduction to the focused issue draws attention to research in the history of textiles and fashion among International Textile and Apparel Association members. It is divided into three parts:...
Dialectics of Complexity: A Five-Country Examination of Lived Experiences on Social Media:

This study examined people’s lived experiences with social media through 10 focus groups with 82 total participants across five countries: Brazil, Germany, Malaysia, South Africa, and the United St...
Main and Moderating Influence of Five-Factor Model Traits on the Association between Intimate Partner Violence and Depressive Symptoms

Intimate partner violence (IPV) is a common problem for young adult women and is associated with symptoms of depression. However, not all women who experience IPV exhibit depressive symptoms. Resea...
Trends and consequences of surgical conversion in the United States

The aim of this study was to identify national utilization trends of robotic surgery for elective colectomy, conversion rates over time, and the specific impact of conversion on postoperative morbidity. Conversion to open represents a hard endpoint for minimally invasive surgery (MIS) and is associated with worse outcomes when compared to MIS or even traditional open procedures. All adult patients who underwent either laparoscopic or robotic elective colectomy from 2013 to 2018 as reported in the American College of Surgeons Quality Improvement Program (ACS-NSQIP) database were included. National trends of both robotic utilization and conversion rates were analyzed, overall and according to underlying disease (benign disease, inflammatory bowel disease (IBD), cancer), or the presence of obesity (body mass index (BMI) ≥ 30 kg/m2). Demographic and surgical risk factors for surgical conversion to open were identified through multivariable regression analysis. Further assessed were overall and specific postoperative 30-day complications, which were risk adjusted and compared between converted patients and the remaining cohort. Of 66,652 included procedures, 5353 (8.0%) were converted to open. Conversion rates were 8.5% for laparoscopic and 4.9% for robotic surgery (p < 0.0001). A decline in conversion rates over the 6-year inclusion period was observed overall and for patients with obesity. This trend paralleled an increased utilization of the robotic platform. Several surrogates for advanced disease stages for cancer, diverticulitis, and IBD and prolonged surgical duration were identified as independent risk factors for unplanned conversion, while robotic approach was an independent protective factor (OR 0.44, p < 0.0001). Patients who had unplanned conversion were more likely to experience postoperative complications (OR 2.36; 95% CI [2.21–2.51]), length of hospital stay ≥ 6 days (OR 2.86; 95% CI [2.67–3.05], and 30-day mortality (OR 2.28; 95% CI [1.72–3.02]). This nationwide study identified a decreasing trend in conversion rates over the 6-year inclusion period, both overall and in patients with obesity, paralleling increased utilization of the robotic platform. Unplanned conversion to open was associated with a higher risk of postoperative complications.
Structural identifiability analysis of PDEs: A case study in continuous age-structured epidemic models

Computational and mathematical models rely heavily on estimated parameter values for model development. Identifiability analysis determines how well the parameters of a model can be estimated from experimental data. Identifiability analysis is crucial for interpreting and determining confidence in model parameter values and to provide biologically relevant predictions. Structural identifiability analysis, in which one assumes data to be noiseless and arbitrarily fine-grained, has been extensively studied in the context of ordinary differential equation (ODE) models, but has not yet been widely explored for age-structured partial differential equation (PDE) models. These models present additional difficulties due to increased number of variables and partial derivatives as well as the presence of boundary conditions. In this work, we establish a pipeline for structural identifiability analysis of age-structured PDE models using a differential algebra framework and derive identifiability results for specific age-structured models. We use epidemic models to demonstrate this framework because of their wide-spread use in many different diseases and for the corresponding parallel work previously done for ODEs. In our application of the identifiability analysis pipeline, we focus on a Susceptible-Exposed-Infected model for which we compare identifiability results for a PDE and corresponding ODE system and explore effects of age-dependent parameters on identifiability. We also show how practical identifiability analysis can be applied in this example.
Leaving a Profession After It’s Left You: Teachers’ Public Resignation Letters as Resistance Amidst Neoliberalism

ContextThough there is a growing field of research on what makes teachers leave, little research includes an analysis of narratives written directly by teachers. Yet, amidst a growing body of teach...
Pharmacologic interventions for antidepressant-induced sexual dysfunction: a systematic review and network meta-analysis of trials using the Arizona sexual experience scale

Background Despite the prevalence of antidepressant-related sexual side effects, comparisons of treatments for these problematic side effects are lacking. Methods To address this, we performed a systematic review and Bayesian network meta-analysis to compare interventions for antidepressant-induced sexual dysfunction in adults. Using PubMed and clinicaltrials.gov, we identified published and unpublished prospective treatment trials from 1985 to September 2020 (primary outcome: the Arizona sexual experience scale [ASEX] score). The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework. Results We identified 57 citations (27 randomized controlled trials, 66 treatment arms, 27 open-label trials, and 3 crossover trials) that evaluated 33 interventions (3108 patients). In the systematic review, 44% (25/57) of trials reported successful interventions; this was more common in open-label (70%, 19/27) compared to placebo-controlled studies (22%, 6/27). In the meta-analysis of placebo-controlled studies that used the ASEX (N = 8), pycnogenol was superior to placebo (standardized mean difference: -1.8, 95% credible interval [CrI]: [-3.7 to 0.0]) and there was evidence that, at a 6% threshold, sildenafil improved sexual dysfunction (standardized mean difference: -1.2, 95% CrI [-2.5 to 0.1]). In the meta-analysis including single-arm studies (15 studies), treatment response was more common with sildenafil, tianeptine, maca, tiagabine, and mirtazapine compared to placebo, but these differences failed to reach statistical significance. Conclusions While heterogeneity across randomized controlled trials complicates identifying the single best intervention, multiple trials suggest that sildenafil ameliorates antidepressant-induced sexual dysfunction. More randomized controlled trials are needed to examine the putative efficacy of other interventions.
Neuropsychological Profiles of Patients with Progressive Apraxia of Speech and Aphasia.

Objective To characterize and compare the neuropsychological profiles of patients with primary progressive apraxia of speech (PPAOS) and apraxia of speech with progressive agrammatic aphasia (AOS-PAA). Method Thirty-nine patients with PPAOS and 49 patients with AOS-PAA underwent formal neurological, speech, language, and neuropsychological evaluations. Cognitive domains assessed included immediate and delayed episodic memory (Wechsler Memory Scale-Third edition; Logical Memory; Visual Reproduction; Rey Auditory Verbal Learning Test), processing speed (Trail Making Test A), executive functioning (Trail Making Test B; Delis-Kaplan Executive Functioning Scale - Sorting), and visuospatial ability (Rey-Osterrieth Complex Figure copy). Results The PPAOS patients were cognitively average or higher in the domains of immediate and delayed episodic memory, processing speed, executive functioning, and visuospatial ability. Patients with AOS-PAA performed more poorly on tests of immediate and delayed episodic memory and executive functioning compared to those with PPAOS. For every 1 unit increase in aphasia severity (e.g. mild to moderate), performance declined by 1/3 to 1/2 a standard deviation depending on cognitive domain. The degree of decline was stronger within the more verbally mediated domains, but was also notable in less verbally mediated domains. Conclusion The study provides neuropsychological evidence further supporting the distinction of PPAOS from primary progressive aphasia and should be used to inform future diagnostic criteria. More immediately, it informs prognostication and treatment planning.
3-D Physical Model for On-chip Power Inductor Design with Evaluation of Airgap Variation Effect

The miniaturization of power inductor helps to achieve high power density of power converters. The development of on-chip power inductors is an important step towards achieving this goal. A 3-D model for an on-chip power inductor is developed in ANSYS®/Maxwell® software in this paper to facilitate the design of on-chip power inductor with on-chip ferrite core. The effects of air gap variation in the on-chip inductor are evaluated using the 3-D physical model and simulations with the on-chip ferrite core. The tradeoff between high inductance value and high saturation value as a function of the air gap between the ferrite layer and winding layer is evaluated from the model and simulations in order to facilitate the optimization and design before fabrication of the complete device.
Bad Company: Shifts in Social Activists’ Tactics and Resources After Industry Crises

Social movement organizations (SMOs) are increasingly using collaborative tactics to engage firms. Implications of this are not well understood by researchers. This study investigates one risk that...
Uptake of Screening and Recurrence of Bicuspid Aortic Valve and Thoracic Aortic Aneurysm Among At-Risk Siblings of Pediatric Probands.

Objective To determine uptake of cardiac screening and recurrence of bicuspid aortic valve (BAV) and thoracic aortic aneurysm (TAA) in a population of at-risk siblings of pediatric probands. Study design A retrospective chart review of pediatric patients with known BAV and/or TAA was performed. Echocardiogram data from identified siblings were collected to determine screening uptake and recurrence of BAV and TAA. Statistical analyses were performed using Wilcoxon signed-rank test and chi-square. Results The cohort included 251 probands and 388 at-risk siblings. Among the siblings, 150 had at least 1 echocardiogram, giving an overall screening uptake of 38.7%. The only factor found to be associated with increased uptake was documented recommendation for screening of first-degree relatives in the proband’s initial cardiology note (P = .03). A total of 11 screened siblings (7.3%) had BAV and 19 had TAA (12.7%), with an overall combined recurrence of 15.3%. Siblings of probands who had both BAV and TAA had increased recurrence of TAA compared with siblings of probands with isolated BAV (16.1% vs 3.9%, respectively). Conclusions Given low uptake in at-risk siblings, the opportunity exists to assess barriers for families in pursuing the recommended screening. Furthermore, the relatively high recurrence of BAV and TAA in at-risk siblings highlights the potential for improved health outcomes through increased screening and early detection. Developing standardized guidelines and promoting early cardiac screening in at-risk siblings while counseling families about hereditary risk for BAV and TAA may help improve uptake and optimize clinical management in at-risk pediatric patients.
CHOICE AND CONTROL: AN ANALYSIS OF PRIVACY VALUES AND PRIVACY CONTROLS

There is incredible and intrinsic, though hidden, power in technology settings, including those set by online platforms. The hidden levers of control embedded within the default settings influence users’ overall experience on platforms and with technology, especially in regard to issues of privacy and security. This paper examines the embedded assumptions and implications of technology and technical design on society. To this end, this study addresses the role and power of social media platforms in developing and applying privacy and security policies and norms for their users. The privacy and security choices by social media platforms affect billions of users worldwide. Further, this study will consider how platforms’ public-facing rhetoric aligns or differs with the actual implementation of privacy policies and privacy and security user settings. The implications of this research may have profound impact in the governance, policy, and regulation of platforms.
Quantifying Uncertainty of Probable Maximum Flood

AbstractProbable maximum flood (PMF) has been used in large hydraulic infrastructure design for decades. However, a complete framework for deriving PMF with uncertainty analysis is lacking. This st...
Production of desensitized, ultrafine PETN powder

Abstract Pentaerythritol tetranitrate (PETN) is a widely studied high explosive (HE), most commonly used in detonator applications. In this work, we use a spray drying technique to manufacture a new “nano-powder” morphology of PETN. The spray dried PETN is several orders of magnitude smaller in particle size than traditionally prepared PETN powders. The spray dried PETN has a mostly spherical and smooth morphology, while traditional crystalline PETN typically has sharp edges and crystal facets. Small-scale sensitivity tests including drop-weight impact, friction, and electrostatic discharge (ESD) indicate the spray dried PETN is less sensitive than traditionally used forms of PETN powders. We also observed no changes in chemical properties (melt temperature and onset of decomposition) after spray drying, and the material remains in the tetragonal, crystalline phase.
Training through Simulation for Digital Battlefield

The vertiginous change in technologies and the increasing sophistication that cyber space present require organization and permanent preparation. However, time, education and training, results too short and not appropriate enough through traditional training methods. Training through simulation may offer proper preparation to fight against new threats that exist in this digital battlefield. The paper presents a preliminary proposal of training through simulation in cyber space.
ARE THE EFFECTS OF THE MACROECONOMY AND SOCIAL POLICIES ON POVERTY DIFFERENT IN RURAL AMERICA

The macroeconomy and social policies can have substantial influences on poverty in the United States. In this paper, I investigate whether these influences differ across metro and nonmetro areas. To do so, using a 16-year panel of state-level data, I estimate state and year fixed effects models separately for metro and nonmetro areas to see if the effects of the macroeconomy and social policies differ between these two areas. These models are estimated using two measures the poverty rate and the squared poverty gap and by family type. I find that cyclical forces have a much stronger effect on the poverty rate in nonmetro areas in comparison to metro areas but the effects are similar for the squared poverty gap; wage growth has a pronounced effect on poverty in metro areas but no effect in nonmetro areas; and state-level social policies have slightly larger effects in nonmetro areas but the effects are small.
Evolution of Macular Findings on Optical Coherence Tomography (OCT) in Papilledema (P2.284)

OBJECTIVE: We used serial optical coherence tomography (OCT) to assess the evolution of macular anatomy in papilledema patients. BACKGROUND: In eyes affected by papilledema, OCT quantifies retinal nerve fiber layer (RNFL) and optic nerve head (ONH) swelling. These improve over time with the underlying condition, sometimes revealing residual axonal loss. Parallel changes in the macula have not been well described. DESIGN/METHODS: We analyzed 40 eyes in 20 patients with optic disc edema associated with increased intracranial pressure (70% idiopathic intracranial hypertension), using spectral-domain OCT. Serial testing was conducted over 3-28 months (mean, 11 months). We measured the thickness and volume of the 6mm-diameter central retina and its individual layers and of the peripapillary RNFL and ONH. We excluded eyes with peripapillary intraretinal fluid or unrelated retinal pathology. RESULTS: Mean total macular volume (TMV) fell non-significantly from 8.38 to 8.23mm 3 in the group, usually in parallel with improvement of ONH and RNFL swelling. TMV fell by >0.08 mm 3 in 25 eyes, but only rose by this value in 2 eyes. Macular change was chiefly attributable to thinning of the RNFL, retinal ganglion cell (RGC) and inner plexiform layers. Four eyes from 2 patients with severe peripapillary RNFL loss showed gradual thickening of the inner nuclear layer (INL) associated with the formation of perifoveal microcysts. CONCLUSIONS: Mild macular thinning often accompanies the resolution of ONH and RNFL swelling in papilledema. This pattern suggests a transition from distended to normal or atrophic RCC axons and cell bodies. Microcystic macular edema originating in the INL in 2 patients was similar to that seen in multiple sclerosis and neuromyelitis optica. We conclude that this finding may sometimes be caused by neuronal loss rather than inflammation. Study Supported by: Not applicable. Disclosure: Dr. Villanueva has nothing to disclose. Dr. Abukhalil has nothing to disclose. Dr. Morrow has received research support from Novartis.
Calculations and analysis of signal processing by various navigation receivers architectures

Calculations of receiver response based on the predicted instrument landing system (ILS) and VHF omnirange (VOR) signals at an observation point are presented. The information contained in the radiated signals are detected by an airborne receiver and processed to provide guidance indications. This is accomplished through the use of heterodyne amplitude modulation (AM) receivers. The ILS signal in space is a composite of the direct and scattered carrier-plus-sidebands and sidebands-only signals. For dual-frequency arrays, this includes both the course and clearance signals. The receiver antenna is designed to pick up only the horizontally polarized component of the electric field available at the antenna. The received signal is then amplified at the radio frequency. The guidance information is computed from the audio tones at the output of the respective audio filters. Several factors which affect the received signal are incorporated in the computation of the detected audio signal. These include the velocity of the aircraft [Doppler effects], multipath, and other spurious effects. Four receiver algorithms are defined and the results from these processing algorithms are compared with actual flight measurements. The VOR receiver operates essentially in the same manner as the ILS receiver, except in the audio filtering stage. Rather than compute a DDM, the VOR receiver employs a phase comparator to compare the phases of two 30 Hz audio signals: the reference audio, and the variable audio. One of the two audio signals is obtained from an amplitude detector while the other is obtained through a frequency discriminator. Two algorithms are implemented, one for the Doppler VOR and the other for the conventional VOR.
GLOBAL HEALTH IMPACT: A BASIS FOR LABELING AND LICENSING CAMPAIGNS?

Most of the world's health problems afflict poor countries and their poorest inhabitants. There are many reasons why so many people die of poverty-related causes. One reason is that the poor cannot access many of the existing drugs and technologies they need. Another, is that little of the research and development (R&D) done on new drugs and technologies benefits the poor. There are several proposals on the table that might incentivize pharmaceutical companies to extend access to essential drugs and technologies to the global poor.(1) Still, the problem remains - the poor are suffering and dying from lack of access to essential medicines. So, it is worth considering a new alternative. This paper suggests rating pharmaceutical and biotechnology companies based on how some of their policies impact poor people's health. It argues that it might be possible to leverage a rating system to encourage companies to extend access to essential drugs and technologies to the poor.
A typology of relational turning point events in college teacher- student relationships

The purpose of this brief report was to develop a typology of relational turning point events between college teachers and students. Participants were 640 undergraduates who were asked whether they could recall a turning point with a teacher, and if so, to report the turning point event in detail. Analysis of the data yielded 6 large categories of turning point events, including instrumental (discussion of grade; discussion of course assignment, course content, course more generally; discussion of college, major, independent study, and/or internships; discussion of course policy/rule), personal (discussion of coursework and personal information; discussion of common interest; compliment; invitation; name used), rhetorical (lecture topic or claim; teaching style), ridicule/discipline, locational, and other person. As the first of a series of studies on relational turning point events between teachers and students, the current study presents new insight into the literature on relational turning points and the larger body of literature on teacher-effectiveness. The current study also offers teachers an understanding of how to establish and build meaningful relationships with students.
Look Who's Moving the Goal Posts Now

The abject failure of Turing's first prediction (of computer success in playing the Imitation Game) confirms the aptness of the Imitation Game test as a test of human level intelligence. It especially belies fears that the test is too easy. At the same time, this failure disconfirms expectations that human level artificial intelligence will be forthcoming any time soon. On the other hand, the success of Turing's second prediction (that acknowledgment of computer thought processes would become commonplace) in practice amply confirms the thought that computers think in some manner and are possessed of some level of intelligence already. This lends ever-growing support to the hypothesis that computers will think at a human level eventually, despite the abject failure of Turing's first prediction.
Survey of opinions of obstetricians concerning official reporting of fetal mortality.

Abstract The data obtained from the survey clarify current practices and make available many valuable suggestions. They show more precisely than was previously known the wide variation that exists among obstetricians in their interpretation and approach to many of the questions being studied. It is apparent that a significant reduction of such differences and improvement in reporting medical information will require a multiple-stage activity which would make the appropriate groups aware of the problems; and would lead to joint consideration of the issues by responsible authoritative bodies in the medical profession, registration and statistical fields, with a resultant agreement on definitions and standards. The survey provides information needed to proceed in this direction.
Studies of halo distributions under beam-beam interaction

The halo distribution due to the beam-beam interaction in circular electron-positron colliders is simulated with a program which uses a technique that saves a factor of hundreds to thousands of CPU time. The distribution and the interference between the beam-beam interaction and lattice nonlinearities has been investigated. The effects on the halo distribution due to radiation damping, misalignment at the collision point, and chromatic effect are presented.
Universal Health Care Coverage in the United States: Barriers, Prospects, and Implications

Universal health care coverage has long been a concern for social workers. This article examines barriers to and prospects for universal coverage in the United States. The article identifies major obstacles to universal coverage, addresses current problems with the U.S. health care system, discusses the debate over Medicare and Medicaid, and considers possible routes to universal coverage. The article also discusses implications for NASW and other supporters of a single-payer system.
The safe haven of a new classicism: the quest for a new aesthetics in Hungary 1904–1912

Seen through the quest for a new metaphysics, the visual arts were interpreted in the framework of the particular sense of progress that the generation of Gyorgy Lukacs developed in the first decade of the twentieth century. They saw Impressionism as the veritable symptom of the deficiencies of their age and dreamed of a great, solid, lasting new Hungarian culture which would transcend the fragmentariness, sociological interests, and ethereality of Impressionism. Although exhibitions of contemporary modernist art were organized in Budapest and the Nagybanya artists’ colony was in contact with the living French art, the nascent aesthetic theory, first of all that of Lukacs, based the appreciation of Post-Impressionism on ideological considerations rather than the artistic particularities of the artists. Central to this aesthetic was the notion of greatness and a sense of metaphysics derived from German idealist philosophy and applied to the art of Cezanne, Gauguin, and the Budapest group The Seekers (founded in 1909, renamed, in 1911, as The Eight), all of whom were appreciated for features pointing in the direction of a new Classicism.
Interaction of bacteriophage T4 tail fiber components with a lipopolysaccharide fraction from Escherichia coli

Abstract The inactivation of T4 phage by an Escherichia coli lipopolysaccharide fraction can be blocked by prior incubation of that fraction with phago or certain phage components. Based on this finding, a quantitative LPS ‡ blocking assay analogous to the serum blocking assay of DeMars (1955) has been developed. The LPS blocking assay, electron microscopy and sedimentation have been used to study the interaction of LPS with purified and partially purified phage precursors from mutant-infected cells. All three methods indicate that the tail-fiberless particle and the tail fiber subunit controlled by gene 34 and carrying the A antigen (A half-fiber) do not interact with LPS. By contrast, the whole tail fiber, as well as the half-fiber controlled by genes 35–38 and carrying the B and C antigens (BC′ half-fiber) do interact with LPS, and appear in electron micrographs to become attached to it by their tips. Moreover, the latter half-fiber interacts to the same extent with LPS whether or not it has been acted upon by the products of genes 35 and 36, suggesting that those genes may control attachment to the A half-fiber rather than interaction with LPS. Since the whole fiber is composed of an A half-fiber and a BC′ half-fiber linked end to end, and since the distal tip of the whole fiber is known to make the initial attachment of the phage to the bacterial surface during the adsorption process, it is concluded that the BC′ half-fiber is distal and the A half-fiber proximal to the baseplate in the completed virus particle.
Tendon strain measurements with dynamic ultrasound images: evaluation of digital image correlation.

The response of musculoskeletal tissues such as ligaments and tendons to loading characterizes the tissue and elucidates its mechanical environment. Such data are essential to advance musculoskeletal tissue engineering, to gain insight into injury mechanisms, and to design and evaluate treatment options that optimize healing. Strain behavior is one way to evaluate tissue such as rotator cuff tendons [1]; not only can altered strain behavior identify abnormal (i.e., partially torn) regions [2], but it can also indicate regions susceptible to tear propagation [3,4]. The importance of strain behavior in pathologies such as tears of rotator cuff tendons has led to a number of ex vivo investigations; many of these utilize optical strain tracking methods using surface markers [1,4–6]. Others have used invasive methods such as intra-operative transducer implantation [7]. Image-based strain measurements hold promise for measuring strains in vivo, and thus transitioning more easily to clinical applications. A digital image pixel tracking algorithm digital image correlation (DIC), originally developed for displacement field evaluation of optically captured images, has become a popular method for evaluating strain [8–11]. DIC has been used in the past to study strain in biological soft tissues such as sheep bone callus [12], human tympanic membrane [13] and stapedial tendon [14], bovine cornea [15], mouse carotid arteries [16], and a human soft tissue phantom [17]. As an optical registration algorithm, DIC enables noncontact measurement of strain on material surfaces. Strain can be tracked using features inherent in the tissue [18]; however, this can be technically challenging in soft tissues because of the uniform white appearance of the collagen fibers in normal light [19], and tracking thus often requires the use of optical markers [20]. Polarized light imaging has been used to generate texture on tendons to allow DIC strain measurement [21]. Ultrasound is commonly used to image tissues in the body, including musculoskeletal tissues. Researchers have used landmarks such as bony markers to measure the deformation of such tissues to estimate strain response to load [22–25]; however, tracking of the texture of the ultrasound image itself would allow more freedom in locations as well as the ability to compare relative strain distributions in a tissue. Such feature tracking is reported for in vivo cardiac ultrasound [26,27], but not tendon tissue. The goal of this study is to demonstrate the efficacy of using DIC to calculate strains directly from the texture present in clinical B-mode ultrasound images by comparing strains measured using this technique with strains measured using optical surface markers (using DIC and manual tracking methods).
Linear left ventricular aneurysmectomy: Modern imaging studies reveal improved morphology and function☆

It remains uncertain whether left ventricular aneurysmectomy (LVA) improves ventricular function and whether LVA improves or distorts left ventricular contour. We applied the powerful imaging techniques of multiple-gated acquisition scanning, intraoperative transesophageal echocardiography, and magnetic resonance imaging to assess functional and morphologic changes after LVA in 75 consecutive patients undergoing LVA by conventional resection and linear closure. Fifty-two patients (69%) underwent concomitant coronary artery bypass grafting, 25 (33%) had directed endocardial resection, and 4 (5%) had valve replacement. The hospital mortality rate was 6.7% (5/75). Actuarial survival rates were 86%, 80%, and 64% at 1 year, 2 years, and 5 years, respectively. Mean anginal class improved from 3.49 to 1.24 (p < 0.0001). Mean congestive heart failure class improved from 3.04 to 1.70 (p < 0.0001). By multiple-gated acquisition scan (48 patients), mean ejection fraction improved from 0.25 preoperatively to 0.33 postoperatively (p < 0.0001). Intraoperative transesophageal echocardiography (28 patients) revealed no cases of distortion and demonstrated normalization of left ventricular contour in 69% of patients. Mean wall motion score improved from 16.4 to 18.8 (p < 0.001). Mean cross-sectional area of the left ventricle decreased from 18.7 cm2 to 12.8 cm2 (p < 0.006). Magnetic resonance imaging confirmed normalization of left ventricular contour without distortion. We conclude that linear LVA is clinically effective and objectively improves left ventricular morphology and function. On this basis, we have extended application of LVA to include patients with at least moderate-sized aneurysms undergoing coronary artery bypass grafting, despite the absence of traditional indications of arrhythmia, embolism, and frank congestive heart failure.
Understanding and Communicating Social Informatics: A Framework for Studying and Teaching the Human Contexts of Information and Communication Technologies, by Rob Kling, Howard Rosenbaum, and Steve Sawyer. Medford, NJ: Information Today, 2005. 240 pp. $39.50 (cloth). ISBN 1-57387-228-8.

Students in various disciplines have been studying information and communication technologies (ICTs) from a variety of perspectives. Nonetheless, the human and organizational contexts of these tech...
Effects of Physical Chemistry and Bioturbation by Estuarine Macrofauna on the Transport of Hydrophobic Organic Contaminants in the Benthos

Effects of macrobenthos on hydrophobic organic contaminant (HOC) transport during two seasons characterized by high (summer) and low (winter) bioturbation were studied in the laboratory. HOC burial...
Determination of Zinc Phosphide Residues in the California Ground Squirrel (Spermophilus beecheyi) by Gas Chromatography-Flame Photometric Detection

Zinc phosphide (Zn3P2) recovery from small mammal tissues is assessed for the first time by an analytical method developed for the determination of Zn3P2 residues in the gastrointestinal (GI) tract...
Phenytoin: Does it reverse tricyclic-antidepressant-induced cardiac conduction abnormalities?

Case reports have appeared describing a beneficial effect of phenytoin in reversing cardiac conduction abnormalities induced by tricylic antidepressant (TCA) overdose. Controlled studies have not been published. The following questions were addressed using intravenous amitriptyline and phenytoin in a rabbit model: 1) Can prophylaxis with phenytoin before amitriptyline poisoning forestall the onset of cardiac abnormalities? 2) Would such prophylactic phenytoin administration allow a higher dose of amitriptyline before death occurs? 3) Would phenytoin reverse the cardiotoxic effects of amitriptyline once in progress? Animals were used in repeated trials with one-week "washout" intervals and served as their own controls in all but the final trial. Prophylactic phenytoin did not change the potency of amitriptyline in inducing abnormal cardiac performance, nor did it allow the animals to be titrated to a higher dose of amitriptyline before death occurred. In 12 animals, phenytoin "rescue" at the point of a widened QRS or arrhythmia was attempted. Two showed improvement; the remainder did not. Because this portion of the experiment was neither blinded nor controlled, nor were respirations or blood pressure monitored, these results must be viewed cautiously. Although our results suggest that prophylactic phenytoin is not useful, its role in therapy of occasional cases requires further investigation.
DIRECT AND INDIRECT EFFECTS OF FIRE ON SHRUB DENSITY AND ABOVEGROUND PRODUCTIVITY IN A MESIC GRASSLAND

Determinants of the balance between grass and woody vegetation in grass- lands and savannas have received considerable attention because of the potential for dra- matic shifts in ecosystem structure and function as one growth form replaces the other. We studied a mesic grassland where recently established ''shrub islands'' are increasing in abundance due to fire suppression. Our objective was to assess the role of the direct effects of fire vs. indirect alterations in resource availability (N and light), as mechanisms that may constrain/facilitate shrub (Cornus drummondii) encroachment. The direct effects of fire in 2001 and 2002 were 100% aboveground mortality of C. drummondiishoots and removal of the detrital layer. Post-fire resprouting resulted in ;600% increase in stem density compared to a 200% increase in shrub islands protected from fire. In burned shrub islands with an added detrital layer, temperature and light penetration to the soil surface were reduced (by 6.58C and to ,3% of full sunlight), but stem density still increased by ;400%. Thus, both the direct effects of fire and the indirect effect on the energy environment increased C. drummondii stem densities. In contrast, N additions did not influence new stem production or aboveground net primary productivity (ANPP; grams per square meter per year), suggesting that N availability did not constrain shrub growth during this study. While fire did not impact total ANPP, it did shift the relative abundance of growth forms. Grass productivity (360.7 6 20.1 g/m 2 (mean 6 1 SE)) was stimulated (an increase of ;30%) by the high light conditions of the post-fire environment, while C. drummondii ANPP (34.2 6 2.4 g/m 2 ) was reduced by ;30%. In shrub islands protected from fire, C. drummondii ANPP was greatest (50.4 6 2.2 g/m 2 ), whereas lower graminoid ANPP (282.5 6 19.9 g/m 2 ) was observed. The persistence of woody vegetation, despite two successive fires, along with a significant reduction in grass ANPP ( ;30%) suggests that once established, C. drummondii can persist and exclude C4 grasses. Thus, restoring fire to mesic grasslands may prevent further conversion to shrub/woodland, but the abun- dance of shrubs is likely to remain unchanged with community structure co-dominated by multiple growth forms.
Proton-Coupled Electron Transfer from Nitrogen. A N−H/N−D Kinetic Isotope Effect of 41.4

An extensive redox chemistry associated with high oxidation state Ru(IV) oxo complexes has been uncovered by kinetic and mechanistic studies. This includes pathways involving well-defined, multiple electron transfer such as O-atom or hydride ion transfer. Large H{sub 2}O/D{sub 2}O solvent kinetic isotope effects have been identified in a series of reactions and interpreted as involving synchronous transfer of an electron and a proton (proton-coupled electron transfer). For example, k(H{sub 2}O)/k(D{sub 2}O) = 30 {+-} 1 for the oxidation of hydroquinone (H{sub 2}O) to benzoquinone (Q) by cis-[Ru{sup IV}(bpy){sub 2}(py)(O)]{sup 2+} at 20.0 {+-} 0.2 C.
Sedimentation of compressible materials: Analysis of batch sedimentation curve

Abstract Batch sedimentation curves for dilute phosphatic slimes to which small amounts of coarser particles were added to hasten settling are analysed. The curves are markedly reverse S-shaped, without a constant settling rate period, and with pronounced asymptotic behaviour indicating compressible material; no flocculants were added but the slimes were observed to flocculate into small clusters of particles which grouped into aggregates. The system is complicated and, as a precursor to an analytical approach, an idealized model is proposed as a framework for future discussion. Several regions of the curve are identified. Each region indicates a specific sedimentation mechanism which predominates over a concentration range. Phenomenological models for the region are proposed and expressed in their simplest mathematical form. The resulting equations consist of logistic, logarithmic, and exponential decay terms, and they fit data within experimental error.