cssi/SciSciGPT-SciSciNet huggingface dataset:
Simulation as Experiment: An Empirical Critique of Simulation Research on Recommender Systems.

Simulation can enable the study of recommender system (RS) evolution while circumventing many of the issues of empirical longitudinal studies; simulations are comparatively easier to implement, are highly controlled, and pose no ethical risk to human participants. How simulation can best contribute to scientific insight about RS alongside qualitative and quantitative empirical approaches is an open question. Philosophers and researchers have long debated the epistemological nature of simulation compared to wholly theoretical or empirical methods. Simulation is often implicitly or explicitly conceptualized as occupying a middle ground between empirical and theoretical approaches, allowing researchers to realize the benefits of both. However, what is often ignored in such arguments is that without firm grounding in any single methodological tradition, simulation studies have no agreed upon scientific norms or standards, resulting in a patchwork of theoretical motivations, approaches, and implementations that are difficult to reconcile. In this position paper, we argue that simulation studies of RS are conceptually similar to empirical experimental approaches and therefore can be evaluated using the standards of empirical research methods. Using this empirical lens, we argue that the combination of high heterogeneity in approaches and low transparency in methods in simulation studies of RS has limited their interpretability, generalizability, and replicability. We contend that by adopting standards and practices common in empirical disciplines, simulation researchers can mitigate many of these weaknesses.
The 3D spatial constraint on 6.1 million amino acid sites in the human proteome

Quantification of the tolerance of protein-coding sites to genetic variation within human populations has become a cornerstone of the prediction of the function of genomic variants. We hypothesize that the constraint on missense variation at individual amino acid sites is largely shaped by direct 3D interactions with neighboring sites. To quantify the constraint on protein-coding genetic variation in 3D spatial neighborhoods, we introduce a new framework called COntact Set MISsense tolerance (or COSMIS) for estimating constraint. Leveraging recent advances in computational structure prediction, large-scale sequencing data from gnomAD, and a mutation-spectrum-aware statistical model, we comprehensively map the landscape of 3D spatial constraint on 6.1 amino acid sites covering >80% (16,533) of human proteins. We show that the human proteome is broadly under 3D spatial constraint and that the level of spatial constraint is strongly associated with disease relevance both at the individual site level and the protein level. We demonstrate that COSMIS performs significantly better at a range of variant interpretation tasks than other population-based constraint metrics while also providing biophysical insight into the potential functional roles of constrained sites. We make our constraint maps freely available and anticipate that the structural landscape of constrained sites identified by COSMIS will facilitate interpretation of protein-coding variation in human evolution and prioritization of sites for mechanistic or functional investigation.
Epistemic Foundationalism (I): Infinite Regresses, Externalism, and Reliabilism

Given the foregoing arguments against epistemic contextualism and epistemic coherentism, we are left with two nonskeptical accounts of inferential justification, namely, inferential justification via infinite justificatory regresses and inferential justification via immediately justified foundations. Although the former account of inferential justification is unpopular at present, the foundationalist must nonetheless eliminate it before he can claim that a regress argument supports his foundationalism. In Chapter I, I have questioned the likely argument that an evidence chain extending infinitely is inadequate for inferential justification since no matter how far back in such a chain we go we always find a proposition that is only inferentially justified. This argument apparently assumes that an evidence chain is adequate for inferential justification only if this chain includes some proposition that is immediately justified. But since this assumption is the very point at issue in the debate between the foundationalist and the proponent of infinite justificatory regresses, the foundationalist cannot rely on the argument in question. We must determine, then, whether the foundationalist can say anything more substantive in opposition to infinite justificatory regresses.
Asymmetric Division and Cell Fate during Sporulation in Bacillus subtilis

At the onset of sporulation, Bacillus subtilis undergoes a switch from binary fission, the mode of cytokinesis it employs during vegetative growth, to asymmetric division, in which a division septum is laid down close to one of the cell poles. This chapter outlines the genetic pathway governing the switch from binary fission to polar septation in B. subtilis, discusses the connection between polar division and the establishment of cell-type-specific gene expression, and finally describes pathways of intercellular communication between the mother cell and forespore chambers of the sporangium. The current model for min gene function in E. coli is based on the idea that there are three potential division sites in the cell, the new site at midcell and the old sites at each pole. The polar septum is intimately involved in the activation of both transcription factors and perhaps can be thought of as an organelle for the establishment of cell fate. Finally, the authors return to the issue of how a null mutation of the spoIIIE gene for the DNA translocase is able to break the otherwise-strict compartmentalization of δF activity. The principal goal in the chapter is to consider sporulation in the context of the developmental problem of the establishment of cell fate.
Microarray Studies (Beyond Histology)

In 1999, the National Cancer Institute (NCI) began a funding initiative called the Director’s Challenge: Toward a Molecular Classification of Tumors, with the goal of defining comprehensive profiles of molecular alterations in tumors that could be used to identify subsets of patients. These molecular profiles would provide the basis for future studies to validate the clinical utility of molecular-based classification schemes. A further goal of this initiative was the development and implementation of a plan for the timely release of the extensive data sets expected to result from these projects. At that time, it was becoming apparent that the knowledge of the entire human genome combined with rapidly improving technology for comprehensive analysis of the 20,000 to 25,000 genes and encoded proteins would provide an opportunity for a deeper understanding of the molecular basis of disease processes that would guide the evolution of improved therapies based on new diagnostic schemes. Specific molecular profiles correlate with important clinical parameters, which should allow physicians to base management decisions on the molecular characteristics of an individual patient’s tumor, and improve a physician’s ability to determine the primary tumor site for tumors of unknown origin at the time of their detection.
Modeling Heavy/Medium-Duty Fuel Consumption Based on Drive Cycle Properties

This paper presents multiple methods for predicting heavy/medium-duty vehicle fuel consumption based on driving cycle information. A polynomial model, a black box artificial neural net model, a polynomial neural network model, and a multivariate adaptive regression splines (MARS) model were developed and verified using data collected from chassis testing performed on a parcel delivery diesel truck operating over the Heavy Heavy-Duty Diesel Truck (HHDDT), City Suburban Heavy Vehicle Cycle (CSHVC), New York Composite Cycle (NYCC), and hydraulic hybrid vehicle (HHV) drive cycles. Each model was trained using one of four drive cycles as a training cycle and the other three as testing cycles. By comparing the training and testing results, a representative training cycle was chosen and used to further tune each method. HHDDT as the training cycle gave the best predictive results, because HHDDT contains a variety of drive characteristics, such as high speed, acceleration, idling, and deceleration. Among the four model approaches, MARS gave the best predictive performance, with an average absolute percent error of -1.84% over the four chassis dynamometer drive cycles. To further evaluate the accuracy of the predictive models, the approaches were first applied to real-world data. MARS outperformed the other three approaches, providing an more » average absolute percent error of -2.2% of four real-world road segments. The MARS model performance was then compared to HHDDT, CSHVC, NYCC, and HHV drive cycles with the performance from Future Automotive System Technology Simulator (FASTSim). The results indicated that the MARS method achieved a comparative predictive performance with FASTSim. « less
On Jacques Servin

Jacques Servin's book is not for citizens of the actual, those who see things for what they are. This collection of experimental short stories instead addresses those who see both meaning and absurdity in the fervent riot of western civilization. In an age when realist fiction domi nates, whether it is magic realism, lyrical realism, or so-called minimalism, it is difficult to find stories written for "alert citizens of the abstract" (14). The fact that these radical experiments entertain as much as they signify is especially gratifying. There are seventy-three stories in the collection, most under two pages, a statistic which makes the labels "sudden fiction" or "short short stories" tempting, although the stories are so connotative and dense, so full of ideas, that those tags seem inadequate. The titles alone are significantly profound and silly: "How the Fish Merchant Turned Out Okay," "Sadness-causing Piece," "How I Discovered Many Things and Became Weil-Known for Helping the Infirm in Moments of Explo sion," and "Only the Wicked Are Marching (A Difficult Hour)," which is used twice. In addition, there is the introduction, itself somewhat fictional, and an "Hortatory Index." The stories are by turns ridiculous, surreal, and dark. "Belles-turning-punk" from Des Moines take a group trip to the beach. As they run toward the water, their feet slip in the sand. Unable to make forward progress, they dig a deep pit with their feet ("Beach Trench: A Fable of Parents"). At a big city convention center, marketing types have beautiful experiences admiring various products ("Sundry Improvement Our Mark"). A person wearing blue eye shadow gets in trouble with New Hampshire authorities for ha bitually "sticking my legs into baby carriages and fending off the req uisite mothers with great swats of my eyebrows" ("Shady I Blush But the Mystery Stands").
A common mechanism for posttranslational activation of plasma membrane receptors

The process for posttranslational acquisition of ligand binding function is remarkably similar for three receptors with dissimilar structures, namely, the insulin, epidermal growth factor, and acetylcholine receptors. These receptors lack the ability to bind ligand immediately after translation, but slowly (t1/2 = 30-45 min) acquire this capacity while in the endoplasmic reticulum. This activation step occurs with similar kinetics for all three receptors and, in each case, required N-linked glycosylation. Several lines of evidence suggest a common mechanism for the acquisition of ligand binding function that involves the rearrangement of metastable disulfide bonds formed during or immediately after translation. This process precedes subunit assembly of both insulin and acetylcholine receptors, which also occurs in the endoplasmic reticulum. The posttranslational processing steps leading to the acquisition of ligand binding function may be an example of a more general process affecting cell surface proteins.
SINOPSIS DE LAS ESPECIES SUDAMERICANAS DE LEPIDIUM (BRASSICACEAE)

Fifty native and 12 naturalized species of Lepidium grow in South America, and a key to all 62 species is presented. Three new species from Argentina ( L. hickenii, L. pedersenii , and L. santacruzensis ) and two from Peru ( L. cuzcoensis and L. werffii ) are described, illustrated, and their relationships to nearest relatives are discussed. The new combination Lepidium crassius is proposed. Furthermore, 19 taxa ( Coronopus didymus var. macrocarpus, C. didymus var. procumbens, L. abrotanifolium var. steinmannii, L. affine, L. argentinum, L. auriculatum, L. bonariense var. pseudovirginicum, L. calycinum var. integrifolium, L. costaricense, L. cumingianum var. orbiculatum, L. cumingianum subsp. berteroanum, L. depressum, L. myrianthum, L. neglectum, L. parodii, L. pubescens var. fallax, L. subvaginatum, L. virginicum subsp. centrali-americanum, Thlaspi campestre ) are lectotypified and 17 others ( Coronopus leptocarpus, C. leptocarpus var. microcarpus, L. boelckii, L. bonariense var. gayi, L. bonariense var. pseudovirginicum, L. brevicaule, L. calycinum, L. danielsii, L. demissum, L. kalenbornii, L. morrisonii, L. peruvianum, L. philippianum var. boliviense, L. raimondii, L. scabrifructum, L. spicatum var. caylx-persistente, L. subvaginatum ) are reduced to synonymy. L. depressum and L. rahmeri are new records for Argentina.
Performance of Parallel Consistency Algorithms

Consistency algorithms are used to reduce the overall computation time for consistent labeling problem which is commonly used in computer vision. We have given parallel algorithms to enforce arc consistency, which has been shown to be inherently sequential[3,6]. Since all three parallel algorithms have the same time complexity on a PRAM, it is necessary to implement them on a parallel processor to determine which one performs best. The results of implementing them on a BBN Butterfly are presented here.
Listening Skills: A Review of the Literature:

This 106-item annotated bibliography includes material on the developmental and educational aspects of listening skills; it was compiled as part of a project to establish the frame of reference for...
IL-10 and Natural Regulatory T Cells: Two Independent Anti-Inflammatory Mechanisms in Herpes Simplex Virus-Induced Ocular Immunopathology

Two prominent anti-inflammatory mechanisms involved in controlling HSV-1-induced corneal immunopathology (stromal keratitis or SK) are the production of the cytokine IL-10 and the activity of natural regulatory T cells (nTregs). It is not known whether, under in vivo conditions, IL-10 and nTregs influence the corneal pathology independently or in concert. In the current study using wild-type and IL-10(-/-) animals, we have assessed the activity of nTregs in the absence of IL-10 both under in vitro and in vivo conditions. The IL-10(-/-) animals depleted of nTregs before ocular infection showed more severe SK lesions as compared with the undepleted IL-10(-/-) animals. In addition, nTregs purified from naive WT and IL-10(-/-) animals were equally able to suppress the proliferation and the cytokine production from anti-CD3-stimulated CD4(+)CD25(-) T cells in vitro. Furthermore, intracellular cytokine staining results indicated that nonregulatory cells expressing B220 and CD25 markers were the major IL-10-producing cell types in the lymphoid tissues of HSV-infected mice. In contrast, in the infected corneas, cells with the CD11b(+)Gr1(+) phenotype along with a minor population of Foxp3(-)CD4(+) and a few F4/80(+) cells produced IL-10. Our current investigations indicate that at least two independent anti-inflammatory mechanisms are involved in limiting the corneal lesions in SK, both of which may need to be modulated to control SK therapeutically.
Surveying History at the International Criminal Tribunal for the Former Yugoslavia

In the law and society literature, it is widely accepted that national criminal trials often fail to produce an adequate account of the historical context in which mass crimes occur. This article evaluates whether this view is applicable to trials at the International Criminal Tribunal for the former Yugoslavia. Drawing on the responses provided by a survey of former prosecutor and defense team members and expert witnesses, empirical evidence is presented with respect to the motivations for including historical evidence in cases and an overall assessment of the historical discussions at the ICTY. Survey results demonstrate agreement among respondents that international criminal trials tend to include more historical evidence than domestic trials, on the grounds that the crimes are more widespread and systematic and involve a collective dimension that requires broader historical analysis. A majority of respondents thought prosecutors use historical evidence to develop their theory of the case and, in genocide trials, such evidence can be relevant to the mental state of the accused. Prosecution and defense respondents profoundly disagreed on whether the ICTY has produced an accurate and comprehensive account of the armed conflicts of the 1990s in the former Yugoslavia. Prosecution respondents generally held that the ICTY’s historical discussions provided valuable insights into the conflict and enhanced the legitimacy of the Tribunal. Defense respondents were more critical of their own expert witnesses, perceived the ICTY judges as unreceptive to defense experts and maintained that the Tribunal’s legitimacy had been undermined by historical discussions. Our correlation analyses identified a divergence between those with two years or less involvement with the tribunal and those with more than 2 years involvement, suggesting that Tribunal tends to "socialize" participants into a shared view of historical evidence. We conclude with a discussion of the potential implications of the survey for creating a shared historical account and promoting reconciliation in the region.
128 Mb/s multiport CMOS binary active-pixel image sensor

A 128/spl times/128 photo-diode active pixel sensor (APS) with an on-chip array sequencing controller and 1b thresholding circuitry processes 8,192-frames/s at a 128 Mb data rate onto a 8 b wide parallel-digital output port. In addition, the on-chip controller can be commanded to output data through either a serial digital port for lower bandwidth requirements or through a serial analog port for higher-resolution off-chip analog-to-digital conversion.
Influenza-associated mortality among children – United States: 2007–2008

Please cite this paper as: Peebles et al. (2010) Influenza-associated mortality among children – United States: 2007–2008. Influenza and Other Respiratory Viruses 5(1), 25–31. Background Since October 2004, pediatric influenza-associated deaths have been a nationally notifiable condition. To further investigate the bacterial organisms that may have contributed to death, we systematically collected information about bacterial cultures collected at non-sterile sites and about the timing of Staphylococcus aureus specimen collection relative to hospital admission. Methods We performed a retrospective, descriptive study of all reported influenza-associated pediatric deaths in 2007–2008 influenza season in the United States. Results During the 2007–2008 influenza season, 88 influenza-associated pediatric deaths were reported. The median age was 5 (range 29 days – 17 years); 48% were <5 years of age. The median time from symptom onset to death was 4 days (range 0–64 days). S. aureus was identified at a sterile site or at a non-sterile site in 20 (35%) of the 57 children with specimens collected from these sites; in 17 (85%) of these children, specimens yielding S. aureus were obtained within three days of inpatient admission. These 17 children were older (10 versus 4 years, median; P < 0·05) and less likely to have a high-risk medical condition (P < 0·05) than children with cultures from the designated sites that did not grow S. aureus. Conclusions S. aureus continues to be the most common bacteria isolated from children with influenza-associated mortality. S. aureus isolates were associated with older age and lack of high-risk medical conditions. Healthcare providers should consider influenza co-infections with S. aureus when empirically treating children with influenza and severe respiratory illness.
The Treatment of Iron Deficiency Anemia

In the normal individual the amount of iron absorbed and lost from the body each day is exceedingly small. There are certain periods during life when body iron requirements are increased; the most important of these is infancy. Here, existing iron stores are rapidly depleted, and a deficient diet can soon produce iron deficiency. Once a full complement of body iron has been accrued, the adult is independent of iron intake and becomes iron deficient only through blood loss. In the production of iron deficiency, iron stores are exhausted before anemia appears. If any question in diagnosis from usual laboratory tests exists, the direct. examination of marrow for hemosiderin will establish the diagnosis. It is of obvious importance to confirm the diagnosis by specific therapy and to determine the cause of the iron depletion. Response to oral iron is highly predictable and failure of response usually in dictates a mistaken diagnosis. In a small but significant group of patients, either unable to take iron because of gastrointestinal symptoms, unable to absorb iron, or in need of iron reserves, parenteral administration of iron has distinct advantages. The saccharated oxide of iron is an effective preparation for this purpose.
Stress Analysis of Viscoelastic Composite Materials

This paper deals with foundations and methods of linear visco elastic analysis of anisotropic composites, including temperature effects. Earlier work on mathematical and thermodynamic bases of constitutive equations and the corresponding principle is re viewed. This principle is then used to relate effective viscoelastic moduli for composites to constituent properties. It is shown that all results from elasticity theory, including upper and lower bounds on moduli, are applicable to viscoelastic materials. Three ap proximate methods of viscoelastic analysis are reviewed and ap plied to three problems: pressurization of an orthotropic cylinder, cooling of a glass fiber embedded in resin, and upper and lower bounds on operational and relaxation shear moduli for a fiber- reinforced composite. Although realistic material properties are used, these methods enable explicit solutions to be derived with out difficulty.
Identifying Novel Biomarkers in Sarcoidosis Using Genome-Based Approaches

This article briefly reviews conventional biomarkers used clinically to (1) support a diagnosis and (2) monitor disease progression in patients with sarcoidosis. Potential new biomarkers identified by genome-wide screening and the approaches to discover these biomarkers are described.
Phosphonate monoester inhibitors of class A β-lactamases

Phosphonate monoesters with the general structure: [formula: see text] are inhibitors of representative class A and class C beta-lactamases. This result extends the range of this type of inhibitor to the class A enzymes. Compounds where X is an electron-withdrawing substituent are better inhibitors than the unsubstituted analogue (X = H), and enzyme inhibition is concerted with stoichiometric release of the substituted phenol. Slow turnover of the phosphonates also occurs. These observations support the proposition that the mechanism of action of these inhibitors involves phosphorylation of the beta-lactamase active site. The inhibitory ability of these phosphonates suggests that the beta-lactamase active site is very effective at stabilizing negatively charged transition states. One of the compounds described also inactivated the Streptomyces R61 D-alanyl-D-alanine carboxypeptidase/transpeptidase.
Interoperability Case Study: Cloud Computing

This case study is part of an ongoing series developed in support of a larger text on interoperability by John Palfrey and Urs Gasser Interop: The Promise and Perils of Highly Interconnected Systems (Basic Books, June 2012). The book is an extension of their 2007 study and paper, “Breaking Down Digital Barriers: When and How ICT Interoperability Drives Innovation” (Berkman Center Research Publication, 2007). Interop: The Promise and Perils of Highly Interconnected Systems focuses on the relationship between interoperability and innovation in the Information and Communication Technology (ICT) environment and beyond. Palfrey and Gasser seek to sharpen the definition of interoperability and identify its relevance for consumers, companies, governments, and the public by examining its driving forces and inhibitors, while considering how it can best be achieved, and why.Authored by research assistants at the Berkman Center for Internet & Society in close collaboration with the authors, the series examines real-world examples where interoperability has played or continues to play a decisive role — in ICT and other sectors, including transportation, retail, and energy. Each case explores how forces such as law, policy, technology, economic incentives, and market innovations drive, or in some cases inhibit, interoperability, and what industry stakeholders seek to achieve via interoperability.Some cases explore well-known innovations, such as the bar code and the UPC system, air traffic control, and the QWERTY keyboard layout. Others touch on more recent examples, including efforts to standardize cell phone chargers in the EU, the evolution of electronic data interchange systems, and digital rights management (DRM) systems. The nature of interoperability and its attendant challenges are also explored in less-traditional contexts, including commons-based knowledge creation models, which require large-scale collective efforts, and complex, next-generation models, like the Internet of Things, cloud computing, and the Smart Grid.
Thermotransport in γ(bcc) U-Zr alloys: A phase-field model study

Abstract Atomic transport in the presence of a temperature gradient, commonly known as thermotransport or the thermomigration phenomenon, was simulated for U–Zr alloys using a phase-field model derived from irreversible thermodynamics. The free energy of the U–Zr system, a necessary ingredient for the phase-field-model, was directly incorporated from the available thermodynamic database. Kinetic parameters such as atomic mobility and heat of transport terms were obtained from experimental values reported in the literature. The model was applied to a single-phase (bcc-γ phase) alloy and to a diffusion couple consisting of two single-phase (bcc-γ phase) alloys of different compositions, both subjected to a constant temperature gradient. Constituent redistribution in the absence and presence of a compositional gradient was examined. An enrichment of Zr with a corresponding depletion of U was observed at the hot end of the initially homogeneous single-phase alloy. A similar atomic transport behavior was observed in the diffusion couple, where the magnitude and direction of the final composition gradient was dictated by the combined influence of atomic mobility and heat of transport terms.
Comparison of ThinPrep and cytospin preparations in the evaluation of exfoliative cytology specimens

BACKGROUND There exists limited literature comparing ThinPrep (TP) with conventional cytospins (CS) in nongynecologic specimens. METHODS The differences between TP and CS were evaluated for a variety of parameters including cellularity, cytologic morphology, specimen preparation, screening time, laboratory cost effectiveness, cytologist preference, and impact on final diagnosis. Eighty-eight cases including 38 urine, 13 respiratory, and 37 body fluids were prepared simultaneously. RESULTS TP and CS demonstrated similar cellular yield in the majority of cases. Cytologists preferred TP in 63 (71.6%) and CS in 6 (6.8%) cases; whereas they indicated no preference in 19 (21.6%) cases. Of 14 abnormal cytologies, a more definitive diagnosis of malignancy was rendered by TP in 6 (42.9%) and by CS in 2 (14.3%) cases. TP demonstrated better nuclear chromatin morphology and more uniform distribution of cells. CS showed larger-sized clusters with better preservation of their architecture compared with smaller-sized clusters and significant shrinkage of cell size in TP. CONCLUSIONS TP was preferred over CS in the majority of cases by both cytotechnologists and pathologists. Cellularity, screening time, and specimen preparation were comparable, although the latter was easier to standardize in TP. In abnormal cases, TP was found to be 3 times more helpful than CS in rendering a definitive diagnosis of malignancy. TP, however, was associated with certain artifacts that cytologists must become familiar with when examining such preparations. Although TP was superior to CS in most cases, the application of both methods may be helpful in selected cases in which the TP diagnosis is not conclusive. Finally, TP was found to be more cost effective than CS. Cancer (Cancer Cytopathol) 2006. © 2006 American Cancer Society.
10 Laparoscopic supracervical hysterectomy

Supracervical hysterectomy is a viable alternative for those individuals requiring uterine extirpation without indications for cervical removal. The laparoscopic approach to this procedure provides even lower morbidity and therefore can enhance clinical outcomes. The procedure is versatile in that most patients are amenable pathologically to this approach, particularly those individuals with large lieomyomata. Five year follow-up data is presented on 236 cases performed by the author including clinical outcomes and morbidity information. The procedure as performed by the author is presented in detail with illustrations of critical aspects of the technique of LSH.
Role of the cyclic adenosine 3',5'-monophosphate response element in efficient expression of the rat thyrotropin receptor promoter.

The "minimal" promoter region of the TSH receptor gene, -195 to -39 basepairs (bp), exhibits basal promoter activity, thyroid specificity, and negative regulation by TSH via its cAMP signal. In FRT thyroid cells and by comparison to pTRCAT5'-199, 5'-deletion mutants of chloramphenicol acetyltransferase (CAT) constructs from -199 to -150 bp of the minimal promoter decrease basal CAT activity by 50%, whereas continued deletion to -146 bp increases activity more than 4-fold. Continued deletion to -131 bp results in basal activity less than that of the -199 bp construct. An octameric cAMP response element (CRE)-like sequence, TGAGGTCA, is within -146 to -131 bp and starts at -139 bp. Its mutation to a consensus CRE (TGACGTCA) or AP1 (TGAGTCA) site or mutation of several residues flanking its 3'-terminus can improve promoter activity as much as 8-fold compared to pTRCAT5'-199. A nonpalindromic mutation to CGAGGACA decreases basal promoter activity to the level of the 199-bp minimal promoter. The CRE-like seque...
Fine Structure of Singly Ionized Helium

The energy difference ($\mathcal{S}$) between the $2^{2}S_{\frac{1}{2}}$ and $2^{2}P_{\frac{1}{2}}$ states of ionized helium has been measured by a pulsed microwave method. Helium atoms are excited to the metastable $2^{2}S_{\frac{1}{2}}$ state of the ion by a micro-second pulse of electrons of about 250-ev energy. After bombardment and after the atoms and ions excited to nonmetastable states have decayed to their respective ground states, a pulse of microwave power is applied to induce the $2^{2}S_{\frac{1}{2}}\ensuremath{-}2^{2}P_{\frac{1}{2}}$ transition. This transition is followed immediately by spontaneous emission of a 40.8-ev photon associated with the $2^{2}P_{\frac{1}{2}}\ensuremath{-}1^{2}S_{\frac{1}{2}}$ transition. The photons are observed by counting photoelectrons with high-speed counters gated on synchronously with the pulses of microwave power. Two different levels of rf power are used alternately to provide a means of normalizing the data for variations in the population of the $2^{2}S_{\frac{1}{2}}$ state.The present value of $\mathcal{S}$ for ${\mathrm{He}}^{+}$ is 14 043\ifmmode\pm\else\textpm\fi{}13 Mc/sec. The stated uncertainty is equal to three times the standard deviation plus an estimated 3 Mc/sec for the uncertainty in the corrections for systematic effects. This result, consistent with previous results, is in agreement with the best available theoretical value of 14 043.2\ifmmode\pm\else\textpm\fi{}3.0 Mc/sec.
Alterations of the prostacyclin-thromboxane ratio in streptozotocin induced diabetic rats.

Abstract Thrombin induced thromboxane A 2 and prostaglandin E 2 production were significantly increased in platelets of streptozotocin induced diabetic rats as compared to non-diabetic control rats, while collagen induced thromboxane A 2 production was decreased. Using exogenous arachidonic acid, prostaglandin E 2 production, but not thromboxane A 2 production, was increased in platelets from streptozotocin treated animals. Prostacyclin production in the diabetic aorta was significantly lowered; however, control levels of prostacyclin production resulted after incubation of the tissue with dipyridamole. Diabetic animals demonstrated a fivefold decrease in the endogenous arterial prostacyclin/platelet thromboxane A 2 ratio when thrombin or ADP was used to induce thromboxane A 2 production. This elevated ratio could be a contributing factor to the vascular complications of diabetes. Dipyridamole, due to its ability to partially normalize this ratio, may be useful as a therapeutic agent in this and related vascular diseases.
Visual event-related potentials index focused attention within bilateral stimulus arrays. II. Functional dissociation of P1 and N1 components

Abstract Event-related potentials (ERPs) were recorded from 12 subjects as they attended to the left or right hemifield of a visual display while fixating a central point. Stimuli were presented to the left or right visual fields on separate trials (unilateral stimuli) or to both fields simultaneously (bilateral stimuli). In different conditions, the stimulus sequences contained only bilateral stimuli, only unilateral stimuli, or a mixture of unilateral and bilateral stimuli. Bilateral stimuli elicited an enhanced positivity lasting from about 75 to 250 msec that was largest at posterior electrode sites contralateral to the attended hemifield. The early phase of this attention-related positivity appeared to be an enhancement of the exogenous P1 component. In contrast, both the posterior P1 and N1 components were enhanced in response to attended unilateral stimuli. Moreover, the N1 attention effect was reduced when the preceding stimulus contained elements in the attended field. It was concluded that modulations of the N1 and P1 components in these experiments represent different aspects of visual spatial attention: N1 may represent the orienting of attention to a task-relevant stimulus, whereas P1 may represent a facilitation of early sensory processing for items presented to a location where attention is already focused.
Transmandibular, circumglossal, retropharyngeal approach for chordomas of the clivus and upper cervical spine. Technical note.

Extensive clival tumors that involve both the midline and lateral skull base compartments, or those that extend inferiorly to the anterior cervical spine, are difficult to expose in a wide fashion using any of the transmaxillary, transoral, or transcervical routes. In the transmandibular, circumglossal, retropharyngeal (TCR) approach wide access of this region can be obtained, thus allowing for a more complete resection of tumor and infiltrated bone. It also provides for an improved ability to perform dural reconstruction, should it be necessary. Over the past 4 years four patients with extensive clival chordomas underwent resection via the TCR approach. Gross-total resection was achieved in two patients, a greater than 98% resection in one patient, and a greater than 95% resection in the fourth patient. The surgical technique, all approach-related complications and morbidity, and patient outcome are discussed. If an expanded exposure of the clivus is necessary, the TCR approach is a good choice as well a...
Great oaks from little acorns

Comment on Pui et al, page [2690][1] Prognosis in childhood ALL has been improved with early intensification of therapy; stratification of treatment intensity according to risk of relapse can preserve this efficacy while limiting unnecessary toxicities. P rognosis in any illness depends upon
Effects of two tranquilizers, reserpine and chlorpromazine, on neurosecretory cells and the ovary of the fiddler crab, Uca pugilator

Abstract 1. 1. Reserpine produced alterations in neurosecretory cell types I and II in the eyestalk, brain, and thoracic ganglion, most notably a decrease in the amount of stored neurosecretory material. 2. 2. The ovarian index decreased, but the oocyte area increased in the reserpinized crabs. 3. 3. Chlorpromazine did not produce any significant changes in the structure of cell types I and II. In spite of having a normal area, the oocytes in the chlorpromazine injected crabs were devoid of yolk. 4. 4. Neurosecretory cell type III showed no change.
Sphingosine-1-phosphate as second messenger in cell proliferation induced by PDGF and FCS mitogens.

GROWTH signalling networks that use glycerophospholipid metabolites as second messengers have been well characterized1,2, but less is known of the second messengers derived from sphingolipids3,4, another major class of membrane lipids. A tantalizing link between sphingolipids and cellular proliferation has emerged from the discovery that the sphingolipid metabolites sphingosine and sphingosine-1-phosphate stimulate growth of quiescent Swiss 3T3 fibroblasts by a pathway that is independent of protein kinase C5,6. Sphingosine-1-phosphate is rapidly produced from sphingosine and may mediate its biological effects6. Furthermore, sphingosine-1-phosphate triggers the dual signal transduction pathways of calcium mobilization6,7 and activation of phospholipase D8, prominent events in the control of cellular proliferation. Here we report that activation of sphingosine kinase and the formation of sphingosine-1-phosphate are important in the signal transduction pathways activated by the potent mitogens platelet-derived growth factor (PDGF) and fetal calf serum (FCS).
Identification of a chloroplast division mutant coding for ARC6H, an ARC6 homolog that plays a nonredundant role.

Abstract A chloroplast division mutant arc6h was identified. ARC6H , a single Arabidopsis gene, is a homolog of ARC6 (accumulation and replication of chloroplasts mutant 6). arc6h produces only 1–13 enlarged chloroplasts/cell, with a median of 7. ARC6H rescued the loss of chloroplast division phenotype. Although arc6h appeared normal in tissue culture, plants were smaller in soil. Significant structural differences indicate that ARC6H and ARC6 are not functionally redundant. In contrast to ARC6, ARC6H lacks a J-domain characteristic of Hsp70 partner proteins, and has two transmembrane segments instead of one, indicating a different membrane topology. The arc6h mutation produces a stop codon deleting the sequence coding for a C-terminal region of ARC6H predicted to extend into the stroma. In transient expression assays a preprotein reporter with a putative transit peptide and the N-terminus of ARC6H fused to YFP was indeed imported into wild type chloroplasts. In some cells, YFP fluorescence was concentrated at the ends, or poles, of chloroplasts, similar to proteins required late in chloroplast division. Our results indicate that upon preprotein import, an N-terminal 10 amino acid region of ARC6H plays a key role in determining this novel localization pattern that reflects a specialized function for ARC6H as chloroplasts divide.
Application of fly ash in the agglomeration of reactive mine tailings

Agglomeration is one of the most effective methods of dealing with reactive mine tailings in the prevention of acid mine drainage. The agglomeration process, accomplished with the use of a conventional binder such as Portland cement, immobilizes the reactive components of the mine tailings and results in the formation of strong pellets which remain impervious to weathering and leaching. The objective of this study was to evaluate the fly ash as a binder, either by itself or in combination with cement, in the mitigation of acid mine drainage caused by the reactive tailings. Two different acid mine tailings samples differing in their reactivities were chosen. These tailings were obtained from Noranda, Quebec, Canada and Cyprus Thompson Creek, Clayton, Idaho. The fly ash was obtained from Mineral Specialities Inc., Billings, Montana. Agglomeration tests were performed with fly ash and Portland cement. The crushing strength and the leachability of the cured agglomerates were evaluated. Preliminary results indicate that the use of fly ash significantly reduces the requirement of cement without any decrease in strength and immobilization effect. In fact, it was shown that the fly ash improved crushing strength of the agglomerates. This increase was substantial in the case of reactive tailings (Noranda). The leaching (simulated TCLP) tests performed on the Noranda Tailings agglomerates prepared using fly ash/cement resulted in the much lower level of extractable ions concentration and well below the regulatory level than from the agglomerates prepared using either fly ash or cement alone.
Pyrimidine base and ribonucleoside utilization by the Pseudomonas alcaligenes group

Pyrimidine base and ribonucleoside utilization was investigated in the two type strains of thePseudomonas alcaligenes group. As sole sources of nitrogen, the pyrimidine bases uracil, thymine and cytosine as well as the dihydropyrimidine bases dihydrouracil and dihydrothymine supported the growth ofPseudomonas pseudoalcaligenes ATCC 17440 but neither these bases nor pyrimidine nucleosides supportedPseudomonas alcaligenes ATCC 14909 growth. Ribose, deoxyribose, pyrimidine and dihydropyrimidine bases as well as pyrimidine nucleosides failed to be utilized by eitherP. pseudoalcaligenes orP. alcaligenes as sole carbon sources. The activities of the pyrimidine salvage enzymes nucleoside hydrolase, cytosine deaminase, dihydropyrimidine dehydrogenase and dihydropyrimidinase were detected in cell-free extracts ofP. pseudoalcaligenes andP. alcaligenes. InP. pseudoalcaligenes, the levels of cytosine deaminase, dihydropyrimidine dehydrogenase and dihydropyrimidinase could be affected by the nitrogen source present in the culture medium.
Effects of zirconium and aluminium compounds and pH on the maillard reaction

The influence of aluminium and zirconium compounds and of pH changes on the development of non-enzymic browning on an incubated glucose-glycine system has been studied. The observed decrease in the browning rate is discussed in relation to pH effects on the ionisation of amino acids. A much smaller pH independent effect is also reported.
Bit arrays from row and column sums

A number of fields, especially within ecology, use bit arrays (i.e. matrices with entries either 0 or 1) to study distributions. In particular such an array serves as a presence/absence array to describe the distribution of species (a given row) across islands (a given column). In such an environment one concept is that the total number of species on a given island will stay fixed, as will the total number of islands populated by a given species. Thus a primary constraint is fixed row/column sums.Now we need to create sample bit-matrices that meet these row and column sum constraints. If such matrices are 'properly random' then conclusions are drawn about the actual physical solution. It is not our intent to consider such conclusions, but rather to discuss only the possible ways to generate such bit-matrices and describe a new algorithm for generation.
An exploration of mental health literacy among older African Americans

The intent of this exploratory descriptive study was to examine mental health literacy (MHL) with 28 African American elders who reside in Kentucky. Collectively, all elders were partially literate of mental disorders and familiar with self-help and professional interventions and Alzheimer's and depression were the most recognized mental disorders. An awareness of MHL is an essential first step to understanding African American elders' views about mental health which then can facilitate the design and development of culturally relevant psychoeducational programs geared to this subset of the aging population.
The Hypothalamus and Primary Headache Disorders

A prominent feature of primary headache disorders is the diurnal variation in their timing, and their relationship to sleep. In particular, the temporal and seasonal distribution of cluster headaches and accompanying hormonal changes in migraine, indicate that the circadian system and other sleep and wake generating areas in the hypothalamus may play an important role in their pathophysiology. This article provides a review of the basic neurobiology of circadian rhythms and sleep and its potential implications for understanding the central triggers of some primary headache disorders. The strongest and most direct evidence for a role of the hypothalamus in cluster headache derives from functional brain imaging studies. Furthermore, alteration in the timing and amplitude of hormonal circadian rhythms point to a possible role of the suprachiasmatic nucleus (SCN) in cluster headaches. Improved understanding of the relationship between circadian rhythms, sleep and primary headache disorders is an exciting area of investigation which could lead to innovative circadian and sleep based treatment strategies.
Evaluation of Three Kinetic Equations in Models of Protein Purification Using Ion-Exchange Membranes

The Langmuir, steric hindrance, and spreading equations were evaluated separately in a mathematical model of protein purification using ion-exchange membranes. The spreading equation provided the best fit to experimental breakthrough curves (BTCs) for α-lactalbumin (ALA) and thyroglobulin (THY), followed by the steric hindrance equation, and finally the Langmuir equation. The intrinsic rate of protein adsorption to the membrane was found to be rate-limiting, whereas effects of liquid-phase mass transfer and flow nonidealities were negligible. An adsorption rate constant that decreased with increasing surface coverage was required to fit BTCs that were sharp initially and then broadened dramatically as the membrane approached saturation. Predictions using the spreading equation agreed with literature reports on the spreading of blood proteins such as fibrinogen on polymer surfaces.
Examining science and engineering students' attitudes toward computer science

Concerns have been raised with respect to the recent decline in enrollment in undergraduate computer science majors. Women are one subpopulation that is severely underrepresented. To better understand the factors that discourage students, both males and females, from pursuing degrees in computer science, a valid and reliable survey is needed. This type of instrument would support the quantitative tracking of attitudinal changes with respect to the field overtime as well as attitudinal comparisons across various subpopulations. This paper describes a survey which is being developed based on current research in computer science education at the Colorado School of Mines through support of the National Science Foundation. Based on the results of a factor analysis and with respect to the pilot population (Colorado School of Mines undergraduate students), there is evidence to support the assertion that this instrument is accurately measuring the five constructs that it was designed to assess.
What makes a good programmer

An examination of the relationship of values, cognitive ability, and personality as predictors of object-oriented programming performance.