cssi/SciSciGPT-SciSciNet huggingface dataset:
A combined EM and proteomic analysis places HIV-1 Vpu at the crossroads of retromer and ESCRT complexes: PTPN23 is a Vpu-cofactor

Abstract The HIV-1 accessory protein Vpu modulates membrane protein trafficking and degradation to provide evasion of immune surveillance. Targets of Vpu include CD4, HLAs, and BST-2. Several cellular pathways co-opted by Vpu have been identified, but the picture of Vpu’s itinerary and activities within membrane systems remains incomplete. Here, we used fusion proteins of Vpu and the enzyme ascorbate peroxidase (APEX2) to compare the ultrastructural locations and the proximal proteomes of wild type Vpu and Vpu-mutants. The proximity-omes of the proteins correlated with their ultrastructural locations and placed wild type Vpu near both retromer and ESCRT-0 complexes. Hierarchical clustering of protein abundances across the mutants was essential to interpreting the data and identified Vpu degradation-targets including CD4, HLA-C, and SEC12 as well as Vpu-cofactors including HGS, STAM, clathrin, and PTPN23, an ALIX-like protein. The Vpu-directed degradation of BST-2 required PTPN23 but not the retromer subunits. These data suggest that Vpu directs targets from sorting endosomes to degradation at multi-vesicular bodies via ESCRT-0 and PTPN23. Author Summary Vpu triggers the degradation or mis-localization of proteins important to the host’s immune response. Vpu acts as an adaptor, linking cellular protein targets to the ubiquitination and membrane trafficking machinery. Vpu has been localized to various cellular membrane systems. By fusing wild type Vpu and Vpu-mutants to the enzyme ascorbate peroxidase, we defined the cellular proteome in proximity to Vpu and correlated this with the protein’s location. We found that wild type Vpu is proximal to ESCRT proteins, retromer complexes, and sorting and late endosomal proteins. Functionally, we found that the Vpu-mediated degradation of the innate defense protein BST-2 required PTPN23, an ALIX-like protein, consistent with our observation of Vpu’s presence at the limiting membranes of multi-vesicular bodies.
Defragmenting the Day: The Effect of Full-Day Continuity Clinics on Continuity of Care and Perceptions of Clinic.

Traditional half-day continuity clinics within primary care residency programs require residents to split time between their assigned clinical rotation and continuity clinic, which can have detrime...
The Rediscovery of the Conjuncture

This chapter responds to the crisis in conjunctural analysis through a philological approach to Gramsci’s original texts. It has located both relatively recently translated and untranslated passages that disrupt and alter the path of the discussion or the debate around conjunctural analysis but, more importantly, it provides a basis for the reinterpretation of the cultural studies project and its relationship to its most popular foundation in the Center for Contemporary Cultural Studies in general, and Stuart Hall’s work, in specific. This chapter has two goals: It explores the methodological and conceptual foundations of conjunctural analysis in cultural studies research and it suffuses the premises of such analysis with crucial, new, and transformative text from Gramsci’s work. It then turns to and intervenes in current and ongoing debates about the specification of conjunctural analysis by offering a new approach that directly addresses the crisis in conjunctural analysis, that there is no theorized method for conjunctural analysis as it pertains to the recognition of a conjunctural shift or the emergence of an organic crisis.
Identification of Symptom Clusters Among Midlife Menopausal Women with Metabolic Syndrome.

The aim of this study was to identify and compare symptom clusters in midlife menopausal women with and without metabolic syndrome based on symptom occurrence and severity dimension through seconda...
Estimating simazine treated area in watersheds based on annual stream loads.

Existing data in the United States are insufficient for estimating pesticide-treated crop areas at the watershed scale. The objective of this research was to evaluate an approach for estimating simazine usage on corn (Zea mays L.) based on its transport to streams of the Salt River Basin (SRB) of Missouri, USA. Annual loads of total simazine and atrazine (parent + metabolites) were quantified for seven SRB watersheds from 2005 to 2017. Simazine-treated corn area was computed as the total simazine load (g) divided by total atrazine load (g ha-1 ) on a treated area basis; atrazine was used as surrogate in the absence of treated area simazine load data. From 2005 to 2010, an estimated 3.8-31% of the corn area within SRB watersheds was treated with simazine, and four of six watersheds had <10% of corn treated. In contrast, Long Branch Creek (2005-2017) and its sub-watersheds (2012-2017) had ≥20% of corn area treated with simazine. Key sources of variation in treated area estimates included extremely dry years with little simazine transport and disparities between spring-applied atrazine and fall-applied simazine transport. However, compared with national estimates for the SRB, these results estimated simazine usage that was generally one to two orders of magnitude greater and showed far more spatial and temporal variation among watersheds. These results demonstrated that this broadly applicable output-based method is a significant improvement over existing input-based national data for estimating pesticide usage in watersheds.
Phase Field Models of Free Boundary Problems: Exterior Boundaries Higher Order Equations and Anisotropy

The application of mean field theories to solidification theory is discussed. In particular the role of microscopic anisotropy in both equilibrium and dynamic problems is considered. A review is presented of recent results which lead to an extension of a Gibbs-Thompson relation. The issue of the intersection of the interface with external (container) boundaries is also discussed.
Chapter 8 Mathematical programming models and methods for production planning and scheduling

Publisher Summary This chapter focuses on the mathematical programming decomposition methods that allow large-scale models to be broken down into manageable sub-models, and then systematically reassembled. These methods show considerable promise for time critical scheduling applications, especially when the methods have been adapted for and implemented on parallel computers. The mathematical programming models fall into several categories: linear programming, network optimization, mixed integer programming, nonlinear programming, dynamic programming, multiple criteria optimization, and stochastic programming. The linear programming model assumes that all transformation activities are linear and additive. Network optimization models determine monthly production plans for tools and tool/machine combinations. Nonlinear mixed integer programming models for capacity expansion planning of electric utilities have received considerable attention. The chapter presents stochastic programming with recourse model that explicitly treats uncertainties regarding demand, fuel costs, and environmental restrictions.
Spectrum management reform and the notion of the 'spectrum commons'

Spectrum management is an extremely important part of telecommunications policy and regulation. The allocation of spectrum for particular uses, and development of specific technical and service rules governing those allocations, are crucial determinants of telecommunications industry structure and performance. Not only does the management of the resource have an enormous impact on a nation's economic and social well-being, it is also of critical importance to the safety of life and property, and to national defense. Fast-growing demand, coupled with rapid technological change, have put increased pressure on the traditional, centralised, often bureaucratic, "command-and-control" methods of managing the resource. One alternative to the traditional, centralised method is moving spectrum management in the direction of a market-oriented solution, wherein property-like rights in the resource are traded on a decentralised basis, more like other resources. Another method for reducing the rigidities in the current system is for policy-makers to move spectrum management in the direction of a "spectrum commons" solution. Under this alternative, anyone can gain access to a particular block of spectrum or set of channels, subject only to certain basic rules. Recently, there has been increased interest in the spectrum commons approach, because of the success of unlicensed spectrum in providing consumer benefits and increased opportunities for entrepreneurial activity. This paper explores the spectrum commons approach and concludes that, even in the face of significant challenges, the potential benefits are significant enough to warrant serious consideration by telecommunications policy-makers in their role as spectrum managers. This conclusion applies not only to developed countries but also to developing countries, where the more decentralised, less bureaucratic approach could empower individuals and communities to expand networks, applications and services on their own initiative.
Oxidation of n-Tetradecane and 1-Tetradecene by Fungi

Cunninghamella blakesleeana (minus strain) and a Penicillium species were grown in a mineral-salts medium containing either n-tetradecane or 1-tetradecene as substrate, and ether extracts of the mycelial mats were analyzed for oxidation products. Extracts from Cunninghamella revealed tetradecanoic acid and 13-tetradecenoic acid from the oxidation of n-tetradecane and 1-tetradecene, respectively, thereby indicating that these hydrocarbons were subject to methyl group oxidation. In contrast to Cunninghamella, the Penicillium oxidized the two substrates by subterminal attacks on methylene rather than methyl groups. This was evidenced by tentative identifications of the following alcohols and ketones from oxidation of the hydrocarbons: tetradecan-2-ol, dodecan-1-ol, tetradecan-2-one, and tetradecan-4-one from n-tetradecane, and tetradecen-4-ol, 13-tetradecen-4-ol, tetradecen-3-ol, 13-tetradecen-4-one, and tetradecen-3-one from 1-tetradecene. A pathway for hydrocarbon oxidation is proposed for subterminal oxidation at the methylene alpha to the methyl group.
A Review of “A ‘Toxic Genre’: The Iraq War Films”

Martin Barker's account of narrative films concerning the Iraq War ends where most others begin: the critical success of Kathryn Bigelow's The Hurt Locker (2008). While the Oscar-winning film was h...
Inactivation and recovery in Kv1.4 K+ channels: lipophilic interactions at the intracellular mouth of the pore.

C-type inactivation is present in many voltage-gated potassium channels and is probably related to ‘slow’ inactivation in calcium and sodium channels. The mechanisms underlying C-type inactivation are unclear, but it is sensitive to mutations on both the extra- and intracellular sides of the channel. We used an N-terminal deleted channel with a valine to alanine point mutation at the intracellular side of S6 (fKv1.4[V561A]ΔN). This construct alters recovery from inactivation and inverts the relationship between C-type inactivation and [K+]o. We used this inverted relationship to examine C-type inactivation and coupling mechanisms between N- and C-type inactivation. The valine to alanine mutation reduces the channel's affinity for both quinidine and the N-terminal domain. However, binding of the N-terminal or quinidine restores normal recovery from inactivation. This suggests that coupling between N- and C-type inactivation is dominated by allosteric mechanisms. The permeation mechanism, driven by a reduction in permeant [K+]o following pore block (which would retard C-type inactivation), contributes minimally to coupling in these channels. We propose that the cytoplasmic half of S6 forms part of the N-terminal binding site, as previously predicted from X-ray crystallography studies in the distantly related KcsA channel. Binding of the N-terminal domain or a positively charged lipophilic compound such as quinidine interacts with the hydrophobic moieties on S6 in the bound state. This binding can orientate S6 into a conformation which resembles the normal C-type inactivated state. This is the probable mechanism by which drug or N-terminal binding increases the rate of C-type inactivation via an allosteric mechanism.
Achieving excellence in medical education

Education matters.- Theoretical insights.- Understanding learners.- Promoting learners.- Educational excellence.- Educational technique.- Obstacles to excellence.- Organizational excellence.- Center of excellence.- Educational leadership.
ACIDOSIS IN PREMATURE INFANTS DUE TO LACTIC ACID

Sixteen premature infants were fed a proprietary lactic-acid milk preparation for 7 to 10 days and were compared to 16 control infants fed non-acidified half-skimmed milk. The experimental group gained less weight (6.5 gm/kg/day) than the controls (14.0 gm/kg/day). This poor weight gain in the experimental group was associated with the production of a metabolic acidosis, the average blood pH decreasing from 7.39 to 7.25, and the average carbon dioxide content in plasma decreasing from 19.6 to 14.8 meq/l. Corresponding averages in the control group showed no appreciable change. A similar study was carried out in six pairs of premature infants, with a formula of half-skimmed milk compared with the identical formula to which lactic acid was added. The results were similar to those in the first study with regard to the poor weight gain and decrease in carbon dioxide content in plasma of the infants fed the acidified milk. Addition of lactic acid to the feeding mixture was followed by a prompt increase in excretion of lactate in the urine, which corresponded to approximately 4% of the lactic acid fed. In four premature infants, 24-hour urine collections demonstrated an increase in excretion of sodium and ammonia, associated with the increased excretion of lactate. The increase in excretion of lactate is considered the major mechanism responsible for the observed acidosis. Studies with intravenous injection of racemic sodium lactate failed to show any deficiency in lactate metabolism in the premature infants. It is suggested that lactic-acid milks not be used for premature infants.
Efficient Simulation of Formal Processor Models

Computer systems under development are routinely modeled by simulators, and formal verification can be integrated into conventional computer system development by reasoning directly about such simulators. Simulators must be extremely fast to be usable in a real development effort. We have crafted a model for a simple processor in the logic of the ACL2 theorem prover that supports both formal analysis and efficient execution, with performance near that of a simulator written in C. We demonstrate our approach using this simple model and indicate how we applied it to our latest microprocessor.
Two Simple Metrics for Quantifying Rainfall Intermittency: The Burstiness and Memory of Interamount Times

AbstractPrecipitation displays a remarkable variability in space and time. An important yet poorly documented aspect of this variability is intermittency. In this paper, a new way of quantifying intermittency based on the burstiness B and memory M of interamount times is proposed. The method is applied to a unique dataset of 325 high-resolution rain gauges in the United States and Europe. Results show that the M–B diagram provides useful insight into local precipitation patterns and can be used to study intermittency over a wide range of temporal scales. It is found that precipitation tends to be more intermittent in warm and dry climates with the largest observed values in the southwest of the United States (i.e., California, Nevada, Arizona, and Texas). Low-to-moderate values are reported for the northeastern United States, the United Kingdom, the Netherlands, and Germany. In the second half of the paper, the new metrics are applied to daily rainfall data for 1954–2013 to investigate regional trends in ...
Serine-70 Is One of the Critical Sites for Drug-induced Bcl2 Phosphorylation in Cancer Cells

Taxoids and other microtubule-damaging drugs are known to induce Bcl2 phosphorylation at the G2-M phase of the cell cycle, with concomitant apoptosis in malignant cells derived from a variety of human malignancies, including leukemia, lymphoma, and breast and prostate cancer. We have investigated the ability of another antineoplastic drug, dolastatin 10, in inducing Bcl2 phosphorylation and apoptosis. We also investigated the effects of a phosphatase inhibitor okadaic acid in the regulation of Bcl2 phosphorylation, cell cycle arrest, and programmed cell death. Moreover, site-directed mutagenesis studies were performed to determine the specific serine residue(s) responsible for drug-induced Bcl2 phosphorylation. Our results indicate that these antimicrotubule agents or okadaic acid can induce posttranslational modification (phosphorylation) of Bcl2 protein at multiple serine residues. Interestingly, mutation of a serine residue at position 70 to alanine can significantly decrease drug-induced posttranslational modification (phosphorylation) of Bcl2 protein. Apparently, Ser70 seems to be a critical site for drug-induced posttranslational modification (phosphorylation) of the Bcl2 protein.
Near-Linear Approximation Algorithms for Geometric Hitting Sets

Given a range space $(X,\mathcal{R})$, where $\mathcal{R}\subset2^{X}$, the hitting set problem is to find a smallest-cardinality subset H⊆X that intersects each set in $\mathcal{R}$. We present near-linear-time approximation algorithms for the hitting set problem in the following geometric settings: (i) $\mathcal{R}$ is a set of planar regions with small union complexity. (ii) $\mathcal{R}$ is a set of axis-parallel d-dimensional boxes in ℝ d . In both cases X is either the entire ℝ d , or a finite set of points in ℝ d . The approximation factors yielded by the algorithm are small; they are either the same as, or within very small factors off the best factors known to be computable in polynomial time.
Pathologic evaluation of radical cystectomy specimens

BACKGROUND The authors evaluated the pathology of radical cystectomy and pelvic lymph node specimens from patients with bladder carcinoma who were enrolled in a cooperative group trial. Their objective was to determine whether current practices conform to suggested pathology practice guidelines for reporting on radical cystectomy and pelvic lymph node specimens. METHODS Overall, 268 patients underwent radical cystectomy with pelvic lymph node dissection over 11 years in a total of 109 diverse geographic locations and types of institutions. Institutions included 50 community hospitals, 36 academic hospitals, and 23 Veterans Administration (VA)/military hospitals, which evaluated 84, 137, and 47 patients, respectively. The quality of pathology examination was assessed based on the original pathology reports of specimens that were submitted according to published practice guidelines. RESULTS Among all types of institutions, pathologic evaluation of radical cystectomy specimens generally was complete for tumor histology, grade, size, location, pathologic stage, lymph node status, prostate involvement, and associated mucosal abnormalities, including ureters and urethra. Perivesical fat (soft tissue) margins were not recorded in 10% of specimens, and 18% of patients did not mention either the presence or the number of lymph nodes. These deficiencies were observed primarily at community and VA hospitals. CONCLUSIONS The overall quality of pathologic examination of radical cystectomy specimens is high. Better reporting of soft tissue margin status and pelvic lymph node counts is needed to achieve compliance with the standards published by evolving practice protocols. Standardized pathologic evaluation and reporting of radical cystectomy specimens will optimize important prognostic information and foster better communication between the pathologist, surgeon, and interested oncologists to benefit patients. Cancer 2004. © 2004 American Cancer Society.
Induction of thymic lymphosarcomas in C57BL/6 mice after inoculation of weakly oncògenic viruses associated with a sub-leukemogenic radiation exposure (1.75 GY × 2)

B-ecotropic retroviruses arise frequently in old or irradiated C57BL/6 mice as a consequence of a genetic recombination between endogenous eco- and xenotropic retroviruses. They are weakly oncogenic and express a very low tropism for thymic cells. However, their activation by X-rays and the subsequent insertion of new proviral sequences in the cell genome of in vivo- and in vitro-passaged tumors suggest that they might play a role in radioleukemogenesis. To study this possibility, a cloned B-ecotropic virus (1223) was injected into C57BL/6 mice subjected to a subleuke-mogenenic irradiation which induses only 7% of thymic lymphosarcomas (TL). When it was injected prior to or after irradiation, 1223 induced respectively 31 % and 19% of TL. The incidence of TL in the different groups closely correlated with virus expression in hemato-poietic tissues during the preleukemic period. Thus, irradiation seems to amplify bone marrow (BM) and thymic cell populations) which play a decisive role in viral expression. A recombinant provirus (presumably the injected 1223) was detected in the genomic DNA of all tumors tested irrespective of the inductive protocol. BM restoration, which does not inhibit TL produced by highly oncogenic passaged viruses, but prevents the development of TL induced by 4 doses of 1.75 Gy, also provided strong protection in the present experiments. The present data support the hypothesis whereby weakly oncogenic B-ecotropic viruses similar to those activated by radiation might be involved in the development of TL.
Assembly of transcriptionally active RNA polymerase I initiation factor SL1 from recombinant subunits

Initiation of ribosomal RNA synthesis by RNA polymerase I requires the promoter selectivity factor SL1, which consists of the TATA-binding protein, TBP, and three associated factors, TAFIS 110, 63, and 48. Here the in vivo and in vitro assembly of functional SL1 complexes from recombinant TAFIS and TBP are reported. Complexes containing TBP and all three TAFIS were as active in supporting transcription from the human ribosomal RNA gene promoter as endogenous SL1, whereas partial complexes without TBP did not efficiently direct transcription in vitro. These results suggest that TAFIS 110, 63, and 48, together with TBP, are necessary and sufficient to reconstitute a transcriptionally active SL1 complex.
Development of large area fast microchannel plate photo-detectors

We report on a cross-disciplined, multi-institutional effort to develop large-scale 'frugal' photo-detectors capable of mm-scale space resolution and pico-second time resolution. This new R&D effort is being led by the High Energy Physics branch within DOE. The large-area fast photodetectors (LAPPD) being developed would have applications in many fields, including particle physics, astrophysics, nuclear sciences, and medical imaging. The basic approach uses novel inexpensive micro channel pores which have been functionalized using a technique called atomic layer deposition. A custom anode and fast electronics are used to readout the photodetector. High quantum efficiency photocathodes are also being explored. The R&D program includes detailed testing and end to end simulations.
Assessing the Rationales for Educational Reforms: An Examination of Policy Claims About Professional Development, Comprehensive Reform, and Direct Instruction

Evaluation studies seldom examine whether the rationales used to argue for an educational reform actually hold up when empirical evidence is examined after the reform has been implemented. This article examines survey data from 3 years of analyses of early reading interventions to examine three rationales that were used to argue for the program. First, there was evidence to support the argument that teachers need time to collaborate about improving educational outcomes. This study found that 2 years of funding for early reading reforms provided a margin of difference for collaborative efforts among teachers to promote reading-related outcomes. Second, the argument that comprehensive reform strategies promote gains in student outcomes was also supported, but not all reform models had their intended effects. Finally, there was no evidence from this study that the direct/explicit approach to reading instruction improved student outcomes, although this claim merits more systematic study in the future.
Classroom criticism and speech attitudes

The speech teacher's use of classroom criticism needs to be tempered by the fact that this criticism has important effects on speech attitudes.
Subtotal colonic replacement of the oesophagus in infancy

Twelve subtotal replacements of the oesophagus by the colon in infants with oesophageal atresia were performed. The right colon was used and it was led through a retrosternal tunnel. This procedure was carried out when the child was at least 8 kg. in weight and was thriving and in good health. The literature on the subject is reviewed and the technique and results in this small series are presented. Although this is an extensive operation and complications are not uncommon, colonic substitution of the oesophagus can confidently be recommended in infancy.
A single intrathecal injection of GABA permanently reverses neuropathic pain after nerve injury.

To investigate whether neuropathic pain is sensitive to spinal GABA levels, GABA was injected intrathecally after nerve injury and sensory behaviors were evaluated. Both thermal and tactile hypersensitivities were permanently reversed at the highest doses of GABA. However, if GABA was injected any later than 2-3 weeks after nerve injury, it was ineffective to prevent such hypersensitivity. This suggests that altered spinal GABA levels contribute to the induction phase of chronic neuropathic pain and that early intervention to restore GABA may prevent the development of that pain.
Radiolysis of the isomeric poly(butyl methacrylates)

A study was made of the effect of gamma radiation on the production of free radicals in polybutyl methacrylates). A mechanism of radiation attack on the polymers is proposed. Free-radical measurements and the determination of the products of irradiation were used in establishing the mechanism. The effects of configuration of the ester chain on radiation susceptibility are discussed. (auth)
A model of H2-enhanced spray combustion

A theoretical model for hydrogen-enhanced spray combustion has been developed. It assumes evaporation limited combustion, requires specification of a droplet ignition temperature, and assumes hydrogen combustion occurs at a given temperature in a zone that is thin compared to the spray combustion zone. The model has been used to investigate how the location of hydrogen combustion affects the flame speed of a spray/hydrogen-air mixture. Flame speeds calculated without hydrogen addition are in good agreement with experimental data. Flame speeds calculated with hydrogen addition support the hypothesis that hydrogen burnup must occur early in the spray combustion zone if substantial improvement in the hydrocarbon burning rate is to be observed.
Somatosensory representation of the cerebellar climbing fiber system in the rat.

Abstract The climbing fiber responses of 542 Purkinje cell were isolated in the vermal and intermediate zones of lobules II to VI of the rat cerebellum. Mechanical stimulation successfully elicited 53% of the isolated climbing fiber responses, whereas the remaining units were unresponsive to any stimulation employed. Of the units elicited by the stimulation, 34% required cutaneous and 66% required deep stimulation. Some proportion of the representation of each body region required either cutaneous or deep stimulation. The hindlimb had the largest representation and accounted for 55% (160/288) of the units. In contrast, the forelimb was only represented by 10% of the units, the tail by 16%, the face by 11% and the remaining 6% of the units by surface regions of the spine, chest and abdomen. On the basis of their proportional representation of body regions, 3 different cortical areas were distinguished: (1) a medial vermis, which consisted predominantly of unresponsive units; (2) a lateral vermis, which included representations of the extremities, trunk and tail; and (3) the intermediate zone, where the only representation of the face was evident. Within each area, the representations formed a disjunctive pattern of irregularly shaped patches and areas of overlap. In comparison with the climbing fiber organization of the cat, the medial vermal unresponsive zone and the patch-like representations of various body surfaces in the rat were similar to the cat, but the proportional representation of various body surfaces and effective stimulus modality were different, which may reflect morphological and behavioral differences between the species.
TH-A-204C-01: Cone-Beam CT: Principles Practicalities and Applications

The topic of C‐arm cone‐beam CT(CBCT) including principles of 3D reconstruction image quality radiation dose quality assurance and clinical applications. The availability of such systems has grown over the past several years particularly in light of performance enhancements gained through the incorporation of a flat‐panel detector(FPD) in the imaging chain in place of conventional x‐ray image intensifiers. Such FPD‐based systems demonstrate increased field of view higher 3D spatial resolution improved noise characteristics and the capability to visualize soft‐tissue structures. Applications include neurovascular and cardiovascular image‐guided interventions as well as a growing spectrum of nonvascular and tumor surgeries. The basic principles of cone‐beam CTimage reconstruction are reviewed (focusing on prevalent implementations of the Feldkmp algorithm) in comparison to conventional fan‐beam filtered backprojection. The influence of image artifacts most relevant to C‐arm cone‐beam CT are reviewed — in particular x‐ray scatter object truncation and the “cone‐beam” artifact. The factors governing 3D image quality are explained with emphasis on the ability to image soft‐tissue structures and issues of radiation dose characterization and quality assurance are discussed. An ever‐increasing spectrum of C‐arm or C‐arm‐like cone‐beam CTsystems is discussed in relation to various applications. Emphasis throughout is in regard to factors most relevant to the practicing medical physicists. Learning Objectives: 1. Basic principles of 3D cone‐beam CT reconstruction 2. Image quality and artifacts most relevant to cone‐beam CT 3. Essential factors pertinent to C‐arm cone‐beam CTquality assurance 4. Spectrum of systems and applications of C‐arm cone‐beam CT
Tec kinases, actin, and cell adhesion.

Summary: The Tec family non-receptor tyrosine kinases have been recognized for their roles in the regulation of phospholipase C-γ and Ca2+ mobilization downstream from antigen receptors on lymphocytes. Recent data, however, show that the Tec family kinase interleukin-2-inducible T-cell kinase (Itk) also participates in pathways regulating the actin cytoskeleton and ‘inside-out’ signaling to integrins downstream from the T-cell antigen receptor. Data suggest that Itk may function in a kinase-independent fashion to regulate proper recruitment of the Vav1 guanine nucleotide exchange factor. By enhancing actin cytoskeleton reorganization, recruitment of signaling molecules to the immune synapse, and integrin clustering in response to both antigen and chemokine receptors, the Tec kinases serve as modulators or amplifiers that can increase the duration of T-cell signaling and regulate T-cell functional responses.
Potential unrecognised costs of clopidogrel pretreatment in acute coronary syndrome

AbstractObjective: To examine adherence in clinical practice to the American College of Cardiology/American Heart Association (ACC/AHA) guideline recommendations of observing a 5-day waiting period after clopidogrel administration before undergoing coronary artery bypass graft (CABG) surgery and to examine the costs of waiting.Methods: This retrospective study used a nationwide inpatient database (Solucient ACTracker) to identify patients who were admitted for acute coronary syndrome (ACS), and who had same-stay CABG. Cost of additional days of stay was estimated using regression analysis.Results: The recommended 5-day waiting was adhered to in 16.9% (n=3,809) of patients. The percentage of patients with ACS undergoing CABG surgery on day 0 was 14.6%. Adherence to the waiting was higher for teaching and rural hospitals; and in female and elderly patients and urgent admissions.Conclusions: The recommended 5-day waiting for CABG surgery after clopidogrel treatment is poorly adhered to in clinical practice. ...
Multinationals, local practice, and the problem of ethical consistency

The business practices of multinational corporations raise many provocative moral issues and offer a touchstone for some fundamental ethical concepts. This essay identifies a wide range of problems but centers on the matter of consistency in corporate policy between foreign and domestic practices and the kind of generality of standards that is required to achieve consistency. Two considerations are singled out for illustrative discussion: wage scales and bribes. Proposals are offered for achieving consistency and generality in each case, the principle of contextual generality for the first and the notion of structural universals for the second.
Examining academic variables affecting the persistence and attainment of black male collegians: a focus on academic performance and integration in the two-year college

The purpose of this study was to investigate the effect of academic variables (e.g., grade point average, major change, informal meetings with faculty) on six year persistence and attainment among black male students in community colleges. Data was collected from the Beginning Postsecondary Students Longitudinal Study and was analyzed using logistic regression. Findings from this study indicated that select variables reflective of academic integration serve as significant predictors of black male persistence and attainment in the community college. These variables included students’ grade point average, whether a student ever received an incomplete, repeating courses for higher grades, withdrawing from courses after the add or drop deadline, and informal meetings with faculty. Implications for future research are provided.
Using Explanatory Item Response Theory Modeling to Investigate Context Effects of Differential Item Functioning for Students With Disabilities

To address whether or not modifications in test administration influence item functioning for students with disabilities on a high-stakes statewide problem-solving assessment, a sample of 868 students (with and without disabilities) from 74 Georgia schools were randomly assigned to one of three testing conditions (resource guide, calculator, or standard administration). The authors describe a conceptual framework for investigating measurement invariance, specifically differential item functioning within the context of assessing students with disabilities. Specifically, we illustrate how the hierarchical generalized linear model, an explanatory model that incorporates item response models into hierarchical models in multilevel settings, can be used to explore issues of measurement invariance traditionally addressed using descriptive item response models, that is, the many-facet Rasch model. Results obtained from the two approaches are reported and discussed.
Robust Landing Using Time-to-Collision Measurement with Actuator Saturation

This paper considers a landing problem for an MAV that uses only a monocular camera for guidance. Although this sensor cannot measure the absolute distance to the target, by using optical flow algorithms, time-to-collision to the target is obtained. Existing work has applied a simple proportional feedback control to simple dynamics and demonstrated its potential. However, due to the singularity in the time-to-collision measurement around the target, this feedback could require an infinite control action. This paper extends the approach into nonlinear dynamics. In particular, we explicitly consider the saturation of the actuator and include the effect of the aerial drag. It is shown that the convergence to the target is guaranteed from a set of initial conditions, and the boundaries of such initial conditions in the state space are numerically obtained. The paper then introduces parametric uncertainties in the vehicle model and in the time-to-collision measurements. Using an argument similar to the nominal case, the robust convergence to the target is proven, but the region of attraction is shown to shrink due to the existence of uncertainties. The numerical simulation validates these theoretical results.
The Future of Social Learning in Software Engineering

Building on time-honored strengths of person-to-person social learning, new technologies can help software developers learn from one another more efficiently and productively. In particular, continuous social screencasting is a promising technique for sharing and learning about new software development tools.
Utterance unmoored: The changing interpretation of the act of writing in the European Middle Ages

Work in the ethnography of communication has barely begun to look at writing, despite the fact that the status of writing has recently preoccupied much of literary theory. The search to locate how writing functions among a culture's communicative practices can involve identifying domains that are unique to it, for example, where some kinds of writing attain a standing such that they are not meant to be understood as the transcription of a testimony or other oral act. Such a possibility is part of our culture but not part of many others, and is, among other things, a significant cognitive development. This article takes a diachronic perspective, back to a moment in our own past when a certain class of writings began to demand a kind of understanding different from that demanded by writing in that culture up to that time. I look at the Middle Ages to examine, inter alia, the written. document putting into question prevailing temporal indices; the move of the act of writing away from an identification with other constatable acts and toward a more oblique and less committed relation to those acts; biblical exegesis as elaborating a new stance of writing through its practice of written gloss; the teaching of writing skills and the professionalization of the writer; and the significance of a renewed use of the cursive hand. The changing status of writing both encouraged and is implicated in the appearance and legitimizing of a set of utterances (and the acts behind them) seen as beneficially unmoored rather than moored, in a space and time of their own. (Ethnography of communication, grammatology, medieval studies, writing)
FLOW CYTOMETRIC IMMUNOPHENOTYPING OF NON-HODGKIN'S LYMPHOMAS AND RELATED DISORDERS

More than two decades have past since the recognition of non-Hodgkin's lymphomas (NHLs) as neoplasms of the immune system. During that time, a vast literature and knowledge base regarding the immunophenotypic and functional characteristics of neoplastic lymphocytes has been developed. Despite the accumulated wealth of knowledge, there remains no consensus as to the exact role of immunotypic and genotypic ancillary procedures in the evaluation of a lymph node biopsy. We review selected literature in this regard and provide an overview of the role of multicolor flow cytometry in establishing the diagnosis of specific NHL and related disorders.
“God of vengeance and of reward?”: The economy and presidential popularity

The relationship between the economy and the political fate of incumbents is reexamined empirically by proposing seven multivariate statistical models representing major approaches found in the literature. These models are tested empirically to determine the influence of aggregate economic conditions on presidential popularity as measured by Gallup Poll data from 1950 to 1974. Analysis suggests (1) that inflation and military expenditures constitute consistently significant influences on popularity and (2) that this influence is best detected in an Almon distributed-lag model which allows for an initial political response that increases cumulatively and remains strong for several months before diminishing.
Changes in lipid composition of tritosomes during lysis.

Abstract Membrane phospholipids and free fatty acids were analyzed after lysis of lysosomes which had engulfed Triton WR 1339 (tritosomes). Significant elevations of lysophosphatidyl choline and lysophosphatidyl ethanolamine were seen. Phosphatidyl choline, phosphatidyl ethanolamine and sphingomyelin decreased significantly. Triglyceride also fell. The released free fatty acids paralleled closely the liberation of β-glucuronidase from the tritosomes. Thus, lipases hydrolyzed endogenous phospholipids and neutral lipids of tritosomes during incubation at 37°C at pH 5.0 to produce significant elevations of lysophospholipids and free fatty acids. The known surface-active properties of these latter compounds raise the possibility of their participation in the process of lysis of the tritosomes.
An exploratory study of political attitudes and acts among child and family services workers

Abstract This study explored the policy advocacy potential, regarded as the propensity to influence public policy, of a diverse group (n = 184) of child and family services workers in one state by assessing their political attitudes and actions through a survey questionnaire. The workers demonstrated typically high trust in the American system of government, moderately high levels of internal political efficacy, and low levels of trust in incumbent political officials. A large majority of respondents believe they can and should act politically on behalf of children and their families but do less than they could. Nine out of ten respondents did at least one political act during the year of the study; 75% acted through organizations or groups; about half took a public stand; half personally contacted an elected official; and only about 20% participated in political campaigns. Internal political efficacy was positively correlated with political activity level; associations between the other political attitudes and activity were not found. Respondent characteristics, including gender, race, age, parental status, education, employment auspices (government, non-government), job status (paid, volunteer), and residence near the state capital (or not), were studied with regard to various political acts. The test for significance indicated only education made a difference; the higher the education, the more activity. The study suggests the political action potential of child and family services workers is underdeveloped and that encouragement and training are needed to increase political participation rates.
Dynamics of spinning test particles in Kerr spacetime

We investigate the dynamics of relativistic spinning test particles in the spacetime of a rotating black hole using the Papapetrou equations. We use the method of Lyapunov exponents to determine whether the orbits exhibit sensitive dependence on initial conditions, a signature of chaos. In the case of maximally spinning equal-mass binaries (a limiting case that violates the test-particle approximation) we find unambiguous positive Lyapunov exponents that come in pairs ± lambda, a characteristic of Hamiltonian dynamical systems. We find no evidence for nonvanishing Lyapunov exponents for physically realistic spin parameters, which suggests that chaos may not manifest itself in the gravitational radiation of extreme mass-ratio binary black-hole inspirals (as detectable, for example, by LISA, the Laser Interferometer Space Antenna).
Fast and faster: A designed variant of the B-domain of protein A folds in 3 μsec

We have introduced the mutation glycine 29 to alanine, designed to increase the rate of protein folding, into the B-domain of protein A (BdpA). From NMR lineshape analysis, we find the G29A mutation increases the folding rate constant by threefold; the folding time is 3 μsec. Although wild-type BdpA folds extremely fast, simple-point mutations can still speed up the folding; thus, the folding rate is not evolutionarily maximized. The short folding time of G29A BdpA (the shortest time yet reported) makes it an attractive candidate for an all-atom molecular dynamics simulation that could potentially show a complete folding reaction starting from an extended chain. We also constructed a fluorescent variant of BdpA by mutating phenylalanine 13 to tryptophan, allowing fluorescence-based time-resolved temperature-jump measurements. Temperature jumps and NMR complement each other, and give a very complete picture of the folding kinetics.
The discursive representation of masculinity in the Freedom Party of Austria ( FPÖ )

Organizations of the extreme right are clearly dominated by men, much more than parties of the political mainstream. But instead of analyzing the specific attractiveness of right-wing extremism for men, gender sensible research in this field has mainly focused on women. This explorative study will reconstruct discourses of masculinity within the Freedom Party of Austria, which is part of the national government since 2000. The analysis of two of the party’s newspapers and of group discussions conducted with young party activists will show the party’s willingness to seize on the insecurities that men experience in the ongoing transformation of gender relations. We can find a general orientation towards a traditional concept of gender roles, but the ways of developing and distributing this knowledge differ widely, depending on the specific conditions in the different political arenas in which the newspapers and the activists are involved.
Safety of direct laryngoscopy as an outpatient procedure

The safety of outpatient direct laryngoscopy has recently been challenged in the literature. We reviewed the first 589 direct laryngoscopies performed at a new outpatient surgery center. There were nine unplanned admissions to the hospital, including five airway emergencies that developed within the first 30 min after extubation. Three patients required reintubation before leaving the operating room. On postoperative telephone follow-up, 9% complained of mild to moderate sore throat. There were no major complications after discharge. We conclude that the risk of airway emergencies after direct laryngoscopy is less than 1% in carefully selected patients. The procedure can be safely performed as an outpatient procedure as long as transportation to a hospital is readily available for the few patients in whom complications arise.
The Korean nuclear deal: How might it challenge the United States?

The October 1994 U.S.‐North Korean Agreed Framework for Resolving the Nuclear Crisis raises a number of questions. Given the terms of the accord, it will be difficult to ascertain whether North Korea is abiding by its obligations and, thus, whether the United States is achieving its policy objectives. In addition, the United States may find itself “hemmed in” by commitments under the agreement. Also at issue is whether the nuclear deal should be considered as if it was a treaty requiring congressional approval.