cssi/SciSciGPT-SciSciNet huggingface dataset:
Conceptual Models of Flow and Transport in the Fractured Vadose Zone.

Panel of Conceptual Models of Flow and Transport in the Fractured Vadose Zone, National Committee for Rock Mechanics, Board on Earth Sciences Resources and National Research Council. National Academy Press, 2101 Constitution Avenue, Washington, DC 20055. 2001. Soft cover, 392 p. $69.00. ISBN 0-309-
Robins on boring out cannon to accomodate heavier shot

Abstract An account is given of one of Benjamin Robins' Tracts concerning an early, elementary consideration of the scaling of gun pieces. He uses the notion to advocate the boring out of certain sizes of cannon to project heavier and therefore more effective shot. His modest reference to the penetration of oak, for the year 1747, is astonishing.
Radiographic indicators of a shared epiphysis in radial polydactyly

Background Thumb epiphyses cannot be visualized on radiographs in infants with radial polydactyly, making it difficult to classify by Wassel type. The purpose of this study was to identify radiographic features that distinguish a separate epiphysis from a shared epiphysis. This may assist in operative planning and establishing prognosis.
Modelling of the cutting temperature distribution under the tool flank wear effect

AbstractThe understanding of cutting temperature distribution at the presence of tool wear can aid in addressing important metal cutting issues such as part surface integrity, tool life and dimensional tolerance under practical operating conditions. The effect of tool wear on the cutting temperature distribution was first modelled by Chao and Trigger and there have been very few followers since. In Chao's model, the primary heat source was assumed to have no effect on the workpiece temperature rise and the chip temperature rise was treated as a bulk quantity. This paper analytically quantifies the tool wear effect by taking into account the contributions of the primary heat source and considering the distribution of chip temperature rise. On the chip side, the primary shear zone is modelled as a uniform moving oblique band heat source and the secondary shear zone as a non-uniform moving band heat source within a semi-infinite medium. On the tool side, the effects of both the secondary and the rubbing heat...
Effects of added trunk load and corresponding trunk position adaptations on lower extremity biomechanics during drop-landings

Although both trunk mass and trunk position have the potential to affect lower extremity biomechanics during landing, these effects are not well understood. Our overall hypothesis stated that both trunk mass and trunk position affect lower extremity biomechanics in landing. Thus, our purpose was to determine the effects of an added trunk load and kinematic trunk adaptation groups on lower extremity joint kinematics, kinetics, and energetics during drop-landings. Twenty-one recreationally active subjects were instrumented for biomechanical analysis. Subjects performed two sets of eight double-limb landings with and without 10% body weight added to the trunk. On lower extremity dependent variables, 2(condition: no load, trunk load)x2(group: trunk extensors vs. trunk flexors) ANOVAs were performed. Condition by group interactions at the hip showed differing responses to the added trunk load between groups where the trunk extensor group decreased hip extensor efforts ( downward decrease 11-18%) while the trunk flexor group increased hip extensor efforts ( upward increase 14-19%). The trunk load increased biomechanical demands at the knee and ankle regardless of trunk adaptation group. However, the percent increases in angular impulses and energy absorption in the trunk extensor group were 14-28% while increases in the trunk flexor group were 4-9%. Given the 10% body weight added to the trunk, the 14-28% increases at the knee and ankle in the trunk extensor group were likely due to the reduced hip extensor efforts during landing. Overall these findings support our overall hypothesis that both trunk mass and trunk position affect lower extremity biomechanics during vertically oriented landing tasks.
Yield improvement for lost mould rapid infiltration forming process by a multistage fractional factorial split plot design

Statistical design of experiments is widely used among scientists and engineers to understand influential factors in a laboratory or manufacturing process. One of the underlying principles of using the statistical design of experiments method is randomisation, each run of experimental settings will be determined completely unsystematically. In practice, especially in a complicated process that consists of multiple stages, randomisation may pose too high a burden on time and cost. In this study, the multistage fraction factorial split plot design is proposed for green yield improvement in a lost mould rapid infiltration process that has been developed to fabricate zirconia ceramic parts. This design allows a relaxation of the randomisation principle so that certain experimental runs can be carried out in convenient groups. The results indicate that the type of immersion chemical and mould coating play a role in improving process yield. Additionally, the results suggest that a mould infiltration machine should be used to improve the reproducibility of the process.
Rhinovirus and the Initiation of Asthma

Purpose of reviewVirus-induced wheezing in infancy is a risk factor for asthma, and recent studies have highlighted the role of rhinoviruses in causing acute illnesses and as a possible contributing factor to chronic asthma.Recent findingsHuman rhinoviruses (HRVs) have long been known as the most co
Cerebrospinal fluid distribution of opioids after intraventricular & lumbar subarachnoid administration in sheep.

The study of opioid distribution in blood and cerebrospinal fluid (CSF) is required to understand pharmacokinetic-pharmacodynamic relationships following lumbar intrathecal (it) and intracerebroventicular (i.c.v.) administration, and to investigate the contributions of spinal or supraspinal sites of action. The sheep model developed for pharmacokinetic study of analgesics allows atraumatic sampling of plasma and CSF after drug administration by the intravenous (i.v.), i.c.v., and it routes in an unanesthetized animal. Five adult female sheep were prepared with femoral vascular catheters, lumbar it and epidural cannulae, i.c.v. cannulae, and cisterna magna cannulae. Hydromorphone, methadone, naloxone, and [14C] sucrose were injected and collected by two methods: 1) injection into the i.c.v. cannula with lumbar CSF samples collected via the lumbar cannula and 2) injection into the lumbar cannula and cisternal CSF samples collected via ventriculocisternal cannula. Hydromorphone, morphine, and [14C] sucrose were detected at 90-105 min in lumbar CSF after i.c.v. injection. Hydromorphone and [14C] sucrose were detected in i.c.v. cerebrospinal fluid at 50 min after lumbar i.t. injection. Methadone was not detected in i.c.v. cerebrospinal fluid after i.t. injection, nor was methadone significantly detected in lumbar CSF after i.c.v. injection. These data indicate that i.c.v. and i.t. administration of lipophilic opioids produces CSF distributions different from those of hydrophilic opioids. This suggests that lipophilic opioids such as methadone or naloxone exert their effects predominantly on tissues near the site of injection. The study of i.t. and i.c.v. opiate administration and CSF pharmacokinetics may therefore have direct clinical implications.
Medicine as business and profession

This paper analyzes one dimension of the frequently alleged contradiction between treating medicine as a business and as a profession, namely the incompatibility between viewing the physician patient relationship in economic and moral terms. The paper explores the utilitarian foundations of economics and the deontological foundations of professional medical ethics as one source for the business/medicine conflict that influences beliefs about the proper understanding of the therapeutic relationship. It then, focuses on the contrast and distinction between medicine as business and profession by critically analyzing the classic economic view of the moral status of medicine articulated by Kenneth Arrow. The paper concludes with a discussion of some advantages associated with regarding medicine as a business.
Relativistic Effects in Nuclear Forces

An attempt is made to reformulate in a relativistically invariant way a phenomenological theory proposed by Johnson and Teller. Such a generalized theory reproduces the earlier results, i.e., saturation of nuclear binding and approximately correct neutron-to-proton ratios. It also avoids the collapse of the nucleus occurring in the nonrelativistic theory for high kinetic energies. The theory predicts as a secondary result an extremely strong spin-orbit coupling which is of the order of magnitude of the phenomenological coupling introduced in the shell model. Furthermore, the theory predicts a strong attraction between nucleons and antinucleons. This could lead to a $^{1}S$ bound state as the ground state of the nucleon---antinucleon system having the properties of a pseudoscalar meson. The strong attraction between antinucleons and nuclear matter also suggests a high value for the collision cross section of antiprotons with nuclei, an effect which has recently been observed.
Monte carlo results for hydrogen bond distributions in liquid water

Abstract Detailed analysXXXs of the hydrogen bonding in water have been made from a Monte Carlo simulation of the liquid at 25°C. Distributions for hydrogen bond numbers and angles are reported. Most monomers are in three or four hydrogen bonds and the average hydrogen bond is bent ca. 20°.
Rainfall at sea.

DURING the winter 1969–1970 we installed an 8 inch tipping-bucket recording rain gauge on a large spar-buoy, Totem, located at 45° 04′ N latitude 124° 44′ W longitude. This is about 56 km west of Cascade Head, Oregon. The water caught in the gauge was retained on the buoy and measured at intervals of approximately 1 month. Four such measurements of total rain were collected between November 22,1969, and April 6, 1970. Table 1 gives the measured rainfall at the buoy for these four periods, as well as measured rainfall at selected sites on the Oregon coast. During two of the periods the rain gauge recording functioned properly and we were thus able to obtain a chronology of the rainfall.
A note on the EOQ-JIT relationship

Abstract Most attempts to reconcile the somewhat antithetical philosophies of economic order quantity (EOQ) and just-in-time (JIT) have focused on the effect of a reduction in setup time and the increase in holding costs. This paper, on the other hand, presents a straightforward mathematical development of the EOQ model that establishes the theoretical basis of JIT. It is shown that the two strategies are consistent when the JIT policy of synchronizing production with demand is achieved.
The leader peptide is not required for post-translational modification by lacticin 481 synthetase

Lantibiotics are post-translationally modified antimicrobial peptides. The modification process features dehydration of Ser and Thr residues to the corresponding dehydroalanine (Dha) and dehydrobutyrine (Dhb) residues and the subsequent conjugate addition by cysteine thiols onto the dehydro amino acids. The ribosomally synthesized peptide precursors contain an N-terminal leader peptide that is not modified during maturation and a C-terminal structural region that is transformed into the lantibiotic. The role of the leader peptide has been the subject of much speculation. Incubation of lacticin 481 synthetase with the structural peptide (with the leader peptide provided in trans) resulted in three of four dehydrations showing that a covalent link between the leader peptide and the structural region is not required. Incubation of lacticin 481 synthetase with the structural peptide in the absence of the leader peptide still resulted in dehydration, although the activity was reduced. These findings show that ...
Rational Expectations Equilibrium: An Alternative Approach

We study a dynamic market process in which traders condition their beliefs about payoff-relevant parameters on past endogenously generated market data and current exogenous data. We say that a market process is informative if the beliefs of traders who receive only endogenously generated market data converge almost surely to the true parameter value. Our main result is that under standard regularity hypotheses, the generic market process is informative. We define an equilibrium as the limit points of the market process. Journal of Economic Literature Classification Numbers: 02 1.026. c 1984 Academic Press. Inc.
Promotion of Lymphocyte Egress into Blood and Lymph by Distinct Sources of Sphingosine-1-Phosphate

Lymphocytes require sphingosine-1-phosphate (S1P) receptor-1 to exit lymphoid organs, but the source(s) of extracellular S1P and whether S1P directly promotes egress are unknown. By using mice in which the two kinases that generate S1P were conditionally ablated, we find that plasma S1P is mainly hematopoietic in origin, with erythrocytes a major contributor, whereas lymph S1P is from a distinct radiation-resistant source. Lymphocyte egress from thymus and secondary lymphoid organs was markedly reduced in kinase-deficient mice. Restoration of S1P to plasma rescued egress to blood but not lymph, and the rescue required lymphocyte expression of S1P-receptor-1. Thus, separate sources provide S1P to plasma and lymph to help lymphocytes exit the low-S1P environment of lymphoid organs. Disruption of compartmentalized S1P signaling is a plausible mechanism by which S1P-receptor-1 agonists function as immunosuppressives.
Ectopic decapentaplegic in the Drosophila midgut alters the expression of five homeotic genes, dpp, and wingless, causing specific morphological defects

The patterns of homeotic gene expression in the Drosophila midgut visceral mesoderm are instrumental in several morphogenetic events, including the formation of the gastric caeca and the positioning of the three midgut constrictions. We demonstrate that a potent regulator of homeotic gene expression in the visceral mesoderm is the secreted growth factor-like molecule encoded by the decapentaplegic (dpp) gene. Ectopic dpp in the visceral mesoderm caused changes in the gene expression of Sex combs reduced, Antennapedia, Ultrabithorax (Ubx), and abdominal-A (abd-A) and disrupted the formation of the gastric caeca and the first and third midgut constrictions. Ectopic dpp also induced expression of teashirt, wingless (wg) and the endogenous dpp gene in the visceral mesoderm and enhanced labial expression in the adjacent endoderm. The patterns of gene expression and the formation of the second midgut constriction in the presence of ectopic dpp are most consistent with a dpp-induced transformation of virtually the entire midgut to cell fates normally seen only in the parasegment (ps)7 and ps8 regions of the midgut. We conclude that dpp is a primary signal in maintaining Ubx expression in the visceral mesoderm in a pattern different from Ubx expression in the embryonic ectoderm and in providing a cell-cell communication mechanism by which Ubx expression influences gene expression across germlayers and across the ps7 to ps8 parasegment boundary in the visceral mesoderm.
The participation of ionic strength and pH in the contraction induced in Vorticella by calcium and magnesium

Abstract 1. 1. Glycerinated stalks of Vorricella convallaria may be induced to contract by the application of either Ca 2+ or Mg 2+ , and the contractions vary complexly as a function of pH. 2. 2. The coiling that occurs in the presence of Mg 2+ is atypical, and the effect of ionic strength is to prevent coiling. 3. 3. The Ca 2+ -contractions are typical of living vorticellid coiling, and those occurring at pH 6.8 and 7.0 are inhibited at low ionic strength and enhanced at high ionic strength. 4. 4. High concentrations of Ca 2+ abolish the ionic strength repression of contraction.
Domestic Costs, the U.S. Public, and the Isolationist Calculus

This article examines and tests two models of the circumstances shaping the extent of the American public&;apos;s isolationist sentiment. The first, termed the “elastic band” model, assumes a constant popular disinclination toward foreign involvements, one that may, at most, temporarily be stretched to accommodate responses to major external threats. A second model assumes the operation of a “cognitive shortcut” based on low-information rationality. It proposes that acceptable levels of domestic involvement depend on the gravity of the domestic opportunity costs of foreign involvement, and it is termed the “domestic costs” model. While the former model implies a constant public resistance to international activism, a resistance that is relaxed only in proportion to the gravity of external threats, the latter model suggests that the U.S. public displays a relatively constant internationalist attitude, and that variations around that threat are largely explained by fluctuations in the perceived domestic opportunity costs of international involvement. Both models are subjected to statistical testing, a testing that vindicates the domestic costs model. Further insights are obtained by examining attitudes toward internationalism as they are affected by levels of education. Although internationalism increases with education, and although levels of education predict differential impacts of the variables encompassed by the model, each segment of the public seems to operate within the general parameters of the “domestic costs” model.
Inequality among the poor of eighteenth century Amsterdam

Abstract This paper examines nearly 1000 poor to middling citizen households from the city of Amsterdam with a view to assessing their place in the larger wealth distribution of the city as preliminarily sketched in the work of Soltow, van Zanden, and others. It utilizes the probate inventories drawn up by the Amsterdam Municipal Orphanage, which when coupled with the marriage, baptism, and burial records of the city archives, allow for the reconstruction of the household circumstances, material, financial, and demographic, of the families associated with the institution. These data yield detailed information about precisely the kind of people who were systematically excluded from the tax registers and financial records which form the basis for our current knowledge about inequality among historical populations. The lower portion of the wealth distribution is described and then linked via housing rental rates to a more complete distribution of the various social classes in the city. Finally, the determinants of inequality within the ranks of the poor are examined and financial assets of even very small amounts are found to be critical in shaping the socio-economic experience of the lower citizenry.
Importance sampling for analysis of direct detection optical communication systems

Analytical solutions of the performance of optical communication systems are difficult to obtain and often, Monte Carlo simulations are used to achieve realistic estimates of the performance of such systems. However, for high performance systems, this technique requires a large number of simulation trials for the estimates to be in a reasonable interval of confidence, with the number of trials increasing linearly with the performance of the system. We apply an importance sampling technique to estimate the performance of direct detection optical systems, where the "gain" of importance sampling over Monte Carlo simulations is shown to increase linearly with the system performance. Further, we use this technique to study the performance of optical communication systems employing avalanche photodetectors as well as fibre-optic code division multiple access systems (FO-CDMA). We also show that the quick simulation technique developed can be used for a wide variety of coding schemes, and for the first time, we present a comparative analysis of the performance of FO-CDMA systems employing optical orthogonal codes and prime sequences. In all cases, it is shown that importance sampling simulations require less than 50-100 trials for estimating error probabilities of 10/sup -10/ and below. >
Personality and Facebook Usage as Predictors of Student Participation in Course Blogs

The use of social media for educational purposes has increased in the past few years. While the use of Facebook and Twitter has been extensively researched, research on the use of blogs in educational contexts has been limited. Course blogs are maintained by the instructor and used as tools to encourage participation, but every student does not participate in these blogs. The current study was an exploratory investigation of the factors that influence students’ participation in course-related blogs. Students enrolled in undergraduate music courses were given the option to create or respond to weekly blog postings by the instructor across two semesters. At the end of each semester, students completed a survey regarding their reactions to the usage of course blog as a participation tool. Findings indicated that conscientiousness and average time spent on Facebook significantly predicted student participation in course blogs. No significant relationships were observed between extroversion, openness to experience, agreeableness, neuroticism and course blog participation. Implications of these findings and directions for future research are discussed.
Effects of polyclonal and monoclonal antibodies to substance P on slow excitatory transmission in rat spinal dorsal horn.

Abstract The effects of bath perfusion of polyclonal and monoclonal antibodies to substance P (SP) on slow excitatory transmission in rat dorsal horn have been investigated by intracellular recording in the immature rat spinal cord slice preparation. Both polyclonal and monoclonal antibodies to SP produced a significant decreasesin the amplitude and the duration of the slow depolarization generated in dorsal horn neurons by high intensity, repetitive dorsal root stimulation or exogenous SP application. The effect of endogenous SP, or SP-related peptide, released during dorsal root stimulation appears likely since bath perfusion of a slice with a normal rabbit serum, or affinity chromatography preadsorbed SP antiserum, or non-specific IgG, or 5-hydroxytryptamine antiserum had no similar depressant effect. These results, if taken together with other experimental evidence, suggest that SP, or SP-like peptide, is in some way involved in a generation of the dorsal root-evoked slow depolarization. In addition, a novel approach is presented for using polyclonal and monoclonal antibodies to SP as pharmacological antagonists. Use of a specific characterized monoclonal antibody for the detection of physiological and pharmacological effects of putative peptide transmitters in vitro opens new avenues for further investigations.
Performance evaluation of different QAM techniques using Matlab/Simulink

This paper presents a performance evaluation approach using the BERTool module provided under Matlab/Simulink software package. It compares different Quadrature Amplitude Modulation (QAM) techniques at different bit rates (8, 16, 32, 64, 128, and 256) based on the Bit Error Rate (BER) versus the Ratio of Bit Energy to Noise Power Spectral Density (Eb/No). The paper provides a detailed model built in Simulink to simulate the QAM techniques along with the results of the performance analysis. Analysis of the impact of variations in the different model parameters on the resulting error rate in the transmitted data has been conducted as well. The motivation for this paper is to review, model, and simulate the QAM technique at its various bit rates using the Matlab/Simulink. Also, this paper serves an educational purpose for researchers in the wireless communication field or related topics by illustrating a step-by-step approach to build the model and simulate the system using the Matlab/Simulink in conjunction with the BERTool used for performance analysis to evaluate different QAM wireless communication techniques. The Monte Carlo simulation is utilized by the BERTool to conduct the performance analysis. The resulting bit error rate from the simulation at the different QAM transmission rates (8 to 256) showed the variation of the error values for each bit rate versus different noise power spectral densities (Eb/No). Also, the results show a comparison between the resulting transmission errors in the received signal at different noise or Eb/No levels. Since Eb/N0 is defined as the ratio of bit energy per symbol to noise power spectral density, in decibels, then increasing this ratio should result in less overall transmission errors and decreasing this ratio should result in higher transmission error. This illustrates how the model captures the variation of the signal power to the power of the applied noise during the transmission process. Also, the model simulates the impact of changing the power of the transmitted signal on the generated Noise Variance by the Additive White Gaussian Noise (AWGN) generator. The simulation illustrates that as the power of the transmitted signal increases, the error rate increases too as a result of the logic implemented in the AWGN generator which in turn increases the noise component imposed to the transmitted signal.
Transcatheter closure of a pulmonary arteriovenous malformation in a patient with hereditary hemorrhagic telangiectasia

Pulmonary arteriovenous malformations (PAVM) are rare pulmonary vascular anomalies. Over 50 % of the cases are associated with hereditary hemorrhagic telangiectasia or Osler-Weber-Rendu Syndrome. Untreated PAVMs progressively enlarge and can cause significant right-to-left shunting. Surgical- and catheter-based approaches have been used in the management of PAVM. We report a case of a 74-year-old man who presented with dyspnea and hypoxia and was found to have a large right-sided PAVM. He underwent percutaneous closure of the PAVM with an Amplatzer device with significant improvement of his symptoms.
Effect of dietary sodium intake on central angiotensinergic pathways

The role of central angiotensinergic pathways in the cardiovascular regulation has been examined using the microinjection of angiotensin peptides and angiotensin receptor antagonists. However, in such studies, neither the overall nor the local level of activity of the renin-angiotensin system is generally known. Herein, physiological changes in the endogenous level of activity of the renin-angiotensin system were produced by alterations in the dietary sodium intake. Microinjection of the angiotensin II AT1 receptor antagonists losartan or candesartan into the rostral ventrolateral medulla produced the bradycardic, depressor and renal sympathoinhibitory responses which were greater in low sodium diet rats with stimulated activity of the renin-angiotensin system than in high sodium diet rats with suppressed activity of the renin-angiotensin system activity. The renal sympathoexcitatory responses to activation of the paraventricular nucleus by microinjection of bicuculline, known to be dependent on the excitatory synaptic inputs to the rostral ventrolateral medulla mediated by AT1 receptors, were greater in low sodium diet rats than in high sodium rats. These observations support the view that physiologically regulated angiotensin peptides of the brain origin exert a local paracrine or autocrine action on sites that influence the renal sympathetic nerve activity.
Molecular cloning of engrailed: a gene involved in the development of pattern in drosophila melanogaster

Summary The engrailed gene acts early in Drosophila embryogenesis and plays an essential role in the processes that establish and maintain the repeating segmental pattern. To begin molecular analysis of the role of the engrailed gene in embryonic pattern formation, we used a chromosomal walk to clone genomic sequences that encompass the locus, and have physically mapped the positions of 15 engrailed mutations. The positions of engrailed rearrangement mutations indicate that the engrailed complementation unit includes a minimum of 70 kb. The locus can be divided into two regions. Rearrangement mutations interrupting the centromere proximal 50 kb of the locus result in embryonic lethality while mutants altered in the distal 20 kb of the locus survive to show morphological abnormalities in several adult segments. It appears that long-range cis interactions play a role in the function of the engrailed gene.
Site-directed Spin Labeling Study of Subunit Interactions in the α-Crystallin Domain of Small Heat-shock Proteins COMPARISON OF THE OLIGOMER SYMMETRY IN αA-CRYSTALLIN, HSP 27, and HSP 16.3

Site-directed spin labeling was used to investigate quaternary interactions along a conserved sequence in the α-crystallin domain of αA-crystallin, heat-shock protein 27 (HSP 27), and Mycobacterium tuberculosis heat-shock protein (HSP 16.3). In previous work, it was demonstrated that this sequence in αA-crystallin and HSP 27 forms a β-strand involved in subunit contacts. In this study, the symmetry and geometry of the resulting interface were investigated. For this purpose, the pattern of spin-spin interactions was analyzed, and the number of interacting spins was determined in αA-crystallin and HSP 27. The results reveal a 2-fold symmetric interface consisting of two β-strands interacting near their N termini in an antiparallel fashion. Remarkably, subunit interactions along this interface persist when the α-crystallin domains are expressed in isolation. Because this domain in αA-crystallin forms dimers and tetramers, it is inferred that interactions along this interface mediate the formation of a basic dimeric unit. In contrast, in HSP 16.3, spin-spin interactions are observed at only one site near the C terminus of the sequence. Furthermore, cysteine substitutions at residues flanking the N terminus resulted in the dissociation of the oligomeric structure. Analysis of the spin-spin interactions and size exclusion chromatography indicates a 3-fold symmetric interface. Taken together, our results demonstrate that subunit interactions in the α-crystallin domain of mammalian small heat-shock proteins assemble a basic building block of the oligomeric structure. Sequence divergence in this domain results in variations in the size and symmetry of the quaternary structure between distant members of the small heat-shock protein family.
Strand-Biased Spreading of Mutations During Somatic Hypermutation

Somatic hypermutation (SHM) is a major means by which diversity is achieved in antibody genes, and it is initiated by the deamination of cytosines to uracils in DNA by activation-induced deaminase (AID). However, the process that leads from these initiating deamination events to mutations at other residues remains poorly understood. We demonstrate that a single cytosine on the top (nontemplate) strand is sufficient to recruit AID and lead to mutations of upstream and downstream A/T residues. In contrast, the targeting of cytosines on the bottom strand by AID does not lead to substantial mutation of neighboring residues. This strand asymmetry is eliminated in mice deficient in mismatch repair, indicating that the error-prone mismatch repair machinery preferentially targets top-strand uracils in a way that promotes SHM during the antibody response.
Does Payment For Order Flow To Your Broker Help Or Hurt You

The presumption is that a broker executing a stock trade for a retail investor will get the investor the best possible price execution for the transaction. In fact, the broker often sells the retail investor’s trade to an intermediary for cash payment. The broker’s motivation to generate dealer profits seems to overcome the broker’s fiduciary responsibility to obtain the best execution price for the customer, raising ethical questions. Purchasers and internalizers of order flow in the market may cause prices quoted on the NYSE to deteriorate, making all investors worse off.
Sequence regularity and geometry of orientation columns in the monkey striate cortex

The striate cortex of the macaque monkey is subdivided into two independent and overlapping systems of columns termed “orientation columns” and “ocular dominance columns.” The present paper is concerned with the orientation columns, particularly their geometry and the relationship between successive columns. The arrangement of the columns is highly ordered; in the great majority of oblique or tangential microelectrode penetrations the preferred orientations of cells changed systematically with electrode position, in a clockwise or counterclockwise direction. Graphs of orientation vs. electrode track distance were virtually straight lines over distances of up to several millimeters; such orderly sequences were often terminated by sudden changes in the direction of orientation shifts, from clockwise to counterclockwise or back. The orientations at which these reversals occurred were quite unpredictable. Total rotations of 180–360° were frequently seen between reversals. In tangential or almost tangential penetrations orientation shifts occurred almost every time the electrode was moved forward, indicating that the columns were either not discrete or had a thickness of less than 25–50 μ, the smallest order of distance that our methods could resolve. In penetrations that were almost perpendicular to the surface, the graphs of orientation vs. track distance were relatively flatter, as expected if the surfaces of constant orientation are perpendicular to the cortical surface. Stepwise changes in orientation of about 10° could sometimes be seen in perpendicular penetrations, each orientation persisting through several clear advances of the electrode, suggesting a set of discrete columnar subdivisions. The possibility of some kind of continuous variation in orientation with horizontal distance along the cortex was not, however, completely ruled out. Occasionally a highly ordered sequence was broken by an abrupt large shift in orientation of up to 90°. Shifts in ocular dominance occurred roughly every 0.25–0.5 mm and were independent of orientation shifts. In multiple parallel penetrations spaced closer than about 250 μ the slopes of the orientation vs. track distance curves were almost the same; reconstruction of these penetrations indicated that the regions of constant orientation are parallel sheets. On crossing perpendicular to these sheets, a total orientation shift of 180° took place over a distance of 0.5–1.0 mm. Column thickness, size of shifts in orientation, and the rate of change of orientation with distance along the cortex seemed to be independent of eccentricity, at least between 2° and 15° from the fovea. A few penetrations made in area 17 of the cat and in area 18 of the monkey showed similar orderly sequences of receptive-field orientation shifts.
Carotid cavernous fistula

Abstract Carotid cavernous fistulae are an uncommon disorder, actually consisting of 2 disease processes. One category is a direct internal carotid artery to cavernous sinus fistula. A second category is the indirect or dural type carotid cavernous fistula. It is the purpose of this article to provide an overview of the anatomy of the cavernous sinus and to discuss the classification, clinical findings, diagnostic imaging evaluation, reasons for misdiagnosis, and treatment options.
Map-based methods for estimating glacier equilibrium-line altitudes

We examine the validity of two methods for estimating glacier equilib- rium-line altitudes (ELAs) from topographic maps. The ELA determined by contour inflection (the kinematic ELA) andthe mean elevation of the glacier correlate extremely well with the ELA determined from mass-balance data (observed ELA). However, the range inglacierelevations above sea level is much larger thanthe variation in ELA,mak- ing this correlation unhelpful. The data were normalized and a reasonable correlation (r 2 ˆ0.59) was found between observed and kinematic ELA.The average of the normal- ized kinematic ELAs was consistently located down-glacier fromthe observed ELA, con- sistent withtheory.Thenormalized mean elevationoftheglacierexhibitedno correlation and suggests that the toe^headwall altitude ratio is not a good approximation for the ELA. Kinematic waves had no effect on the position of the kinematic ELA. Therefore, topographic maps of glacier surfaces can be used to infer the position of the ELA and provide a method for estimating past ELAs from historic topographic maps.
Preparation of two antigens of human liver isoenzymes of alkaline phosphatase

Abstract A convenient standard technique has been developed to prepare human liver isoenzyme (alkaline phosphatase) antigens based on an initial butanol treatment of a tris-homogenate of liver, followed by acetone precipitation, fractionation with ammoniumzsulfate and Sephadex G-200 gel filitration. The bulk of the enzyme was distributed in a bimodal manner, one moiety separating out in 0–30% saturated ammonium sulfate solution and the other, in 50–60% saturated ammonium sulfate. The latter, after Sephadex gel filtration is designated variant A and the former, variant B. Both variants have been characterized on starch gel electrophoresis and with respect to sensitivity to Mg2+, l -phenylalanine and l -homoarginine. Variant A (mol. wt. 280000) corresponds to the fast liver band (6 cm) seen in sera rich in liver isoenzyme and variant B mainly with the isozyme band at or near the origin. These two variants represent two characterized liver antigens capable of producing the desired specific antisera.
Incidence of agonal respirations in sudden cardiac arrest.

Study objective: To discover the frequency of agonal respirations in cardiac arrest calls, the ways callers describe them, and discharge rates associated with agonal respirations. Design: We reviewed taped recordings of calls reporting cardiac arrests and emergency medical technician and paramedic incident reports for 1991. Arrests after arrival of emergency medical services were excluded. Setting: King County, Washington, excluding the city of Seattle. Participants: Four hundred forty-five persons with out-of-hospital cardiac arrests receiving emergency medical services. Interventions: Telephone CPR, emergency medical technicians-defibrillation, and advanced life support by paramedics. Measurements and main results: Any attempts at breathing described by callers were identified, as well as whether agonal respirations could be heard by dispatcher, emergency medical technicians, or paramedics. Agonal respirations occurred in 40% of 445 out-of-hospital cardiac arrests. Callers described agonal breathing in a variety of ways. Agonal respirations were present in 46% of arrests caused by cardiac etiology compared with 32% in other etiologies ( P P P P Conclusion: There is a high incidence of agonal activity associated with out-of-hospital cardiac arrest. Presence of agonal respirations is associated with increased survival. These findings have implications for public CPR training programs and emergency dispatcher telephone CPR programs.
Human capital and Russia's agricultural future

Russian agriculture has rebounded from the depths of the 1990s but significant challenges remain. This article documents deficiencies in rural human capital, specifically, a contracting rural labour force, a shortage of skilled workers, and migratory outflow of the rural young. These problems are compounded by emerging budgetary constraints, slower economic growth and de-mechanisation of agricultural labour. State policy prioritises food production but does not allocate sufficient resources to supporting human capital on which food production depends. As a result, the base of human capital will continue to erode, thereby damaging leadership aspirations and Russian competitiveness in the global food market.
Discrete electro-optic response in lead zirconate thin films from a field-induced phase transition

A discrete transverse electro-optic response associated with a field-induced antiferroelectric–ferroelectric phase transition has been observed to exist in lead zirconate thin films grown on Pt/Ti-coated silicon substrates. The magnitude of the birefringence jump from the antiferroelectric to the ferroelectric state is approximately 2.5 × 10−2. Quantitative correlation between the field-induced birefringence and the polarization was also experimentally studied. The discrete birefringent change in the thin films may be a desirable property for applications in optical switches or other integrated-optical devices.
Quantitative Analysis of Aflatoxins by High-Performance Thin-Layer Chromatography Utilizing a Scientifically Operated Charge-Coupled Device Detector

The use of a scientifically operated charge-coupled device (CCD) for the detection and quantitation of aflatoxins on a high-performance thin-layer chromatographic (HPTLC) plate was investigated. A nebulizer-based sample application system was utilized to quantitatively transfer the sample onto the HPTLC plate without disturbing the sorbent layer. Fluorescence excitation of the aflatoxins was accomplished with an ultraviolet transilluminator, which caused the analytes of interest to emit in the blue-green portion of the visible spectrum. The dynamic range, sensitivity, accuracy, and precision of the system were evaluated. Detection limits of the aflatoxins were determined to be in the low picogram range. The existence of aflatoxins in peanut butter samples was analyzed both quantitatively and qualitatively by using multidimensional TLC. The capabilities of the system for performing real-time monitoring of the separation process were also investigated.
From the Editors: Preparing Early Childhood Educators for 21st Century Children

The notion that educational institutions must prepare the children of today for the 21st century, which will include multiple careers that do not even exist today, is pervasive in educational circl...
The stopping of ions in compounds

Abstract This article reviews the historical scientific interest in the stopping of ions in compounds. A brief survey is made of the experimental and theoretical scientific status of this field to date. Finally, a simple method is described and evaluated to calculate the stopping of ions in compounds based on the details of the molecular bonding of the material. Results are compared with over 100 experimental stopping values for a variety of ions in many compounds. Agreement between experiment and theory averages about 1%.
Toward a model of satisfaction processing in social marketing: The role of knowledge among maintenance stage consumers

Despite agreement on the importance of satisfaction processes to the adoption and maintenance of pro-social behaviors (Andreasen, 1995), social marketing theory in this area is limited. This paper ...
Tunica albuginea cyst: Rare testicular mass

Abstract A case of a benign tunica albuginea cyst as a possible testicular malignancy is presented.
Affect in Electoral Politics

Recent U.S. history provides vivid illustrations of the importance of politicians' emotional displays in subsequent judgments of them. Yet, a review of empirical research on the role of affect (emotion, mood, and evaluation) in electoral politics reveals little work that has focused on the impact of candidates' emotional expression on voters' preferences for them. A theoretical framework is proposed to identify psychological mechanisms by which a target's displays of emotion influence judgments of that target. Findings from the emerging literature on emotions and politics challenge the traditional assumption of political science that voters make decisions based solely on the cold consideration of nonaffectively charged information. The affect and politics literature, although somewhat unfocused and broad, represents an interdisciplinary domain of study that contributes to the understanding of both electoral politics and social interaction more generally.
Noninvasive definition of anatomic coronary artery disease by ultrafast computed tomographic scanning: A quantitative pathologic comparison study

Objectives. The aim of this study was to determine the relation between coronary artery calcification detected by ultrafast computed tomographic scanning and histopathologic coronary artery disease. Background. Recent studies suggest that discrete coronary artery calcification as visualized by ultrafast computed tomographic scanning may facilitate the noninvasive detection of estimation, or both, of the in situ extent of coronary disease. Such quantitative relations have not been established. Methods. Thirteen consecutive perfusion-fixed outopsy hearts (from eight male and five female patients aged 17 to 83 years) were scanned by ultrafast computed tomographic scanning in contiguous 3-mm tomographic sections. The major epicardial arteries were dissected free, positioned longitudinally and scanned again in cross section. Coronary artery calcification in a coronary segment was defined as the presence of one or more voxels with a computed tomographic density 130 Hounsfleld units. Each epicardial artery was sectioned longitudinally, stained and measured with a planimeter for quantification of cross-sectional and atherosclerotic plaque areas at 3-mm intervals, corresponding to the computed tomographic scans. A total of 522 paired coronary computed tomographic and histologic sections were studied. Results. Direct relations were found between ultrafast computed tomographic scanning coronary artery calcium burden and atherosclerotic plaque area and percent lumen area stenosis. However, the range for plaque area or percent lumen stenosis, or both, associated with a given calcium burden was broad. Three hundred thirty-one coronary segments showed no calcification by computed tomography. Although atherosclerotic disease was found in several corresponding pathologic specimens,97% of these noncalcified segments were associated with nonobstructive disease (<75% area stenosis); if no calcification was determined in an entire coronary vessel, all corresponding coronary disease was found to be nonobstructive. To determine the relation between arterial calcification and any atheromatous disease, computed tomographic calcium burden for each segment was paired with the histologic absence or presence of disease. Ultrafast computed tomographic scanning had a sensitivity and specificity of 59% and 90% and a negative and positive predictive value of 65% and 87%, respectively. A direct correlation was found (r = 0.99) between total calcium burden calculated from tomographic scans of the heart as a whole and scans of the arteries obtained in cross section. Conclusions. The detection of coronary calcification by ultrafast computed tomographic scanning is highly predictive of the presence of histopathologic coronary disease, but the use of this technique to define the extent of coronary disease may be limited. However, the absence of coronary calcification at any site is highly specific for the absence of obstructive disease.