cssi/SciSciGPT-SciSciNet huggingface dataset:
Endogenous Human Papillomavirus E6 and E7 Proteins Differentially Regulate Proliferation, Senescence, and Apoptosis in HeLa Cervical Carcinoma Cells

Cervical cancer cells express high-risk human papillomavirus (HPV) E6 and E7 proteins, and repression of HPV gene expression causes the cells to cease proliferation and undergo senescence. However, it is not known whether both HPV proteins are required to maintain the proliferative state of cervical cancer cells, or whether mutations that accumulate during carcinogenesis eliminate the need for one or the other of them. To address these questions, we used the bovine papillomavirus E2 protein to repress the expression of either the E6 protein or the E7 protein encoded by integrated HPV18 DNA in HeLa cervical carcinoma cells. Repression of the E7 protein activated the Rb pathway but not the p53 pathway and triggered senescence, whereas repression of the E6 protein activated the p53 pathway but not the Rb pathway and triggered both senescence and apoptosis. Telomerase activity, cyclin-dependent kinase activity, and expression of c-myc were markedly inhibited by repression of either E6 or E7. These results demonstrate that continuous expression of both the E6 and the E7 protein is required for optimal proliferation of cervical carcinoma cells and that the two viral proteins exert distinct effects on cell survival and proliferation. Therefore, strategies that inhibit the expression or activity of either viral protein are likely to inhibit the growth of HPV-associated cancers.
1/ $f$ Noise Characteristics of MoS 2 Thin-Film Transistors: Comparison of Single and Multilayer Structures

We report on the transport and low-frequency noise measurements of MoS2 thin-film transistors (TFTs) with thin (2–3 atomic layers) and thick (15–18 atomic layers) channels. The back-gated transistors made with the relatively thick MoS2 channels have advantages of the higher electron mobility and lower noise level. The normalized noise spectral density of the low-frequency 1/ $f$ noise in thick MoS2 transistors is of the same level as that in graphene. The MoS2 transistors with the atomically thin channels have substantially higher noise levels. It was established that, unlike in graphene devices, the noise characteristics of MoS2 transistors with thick channels (15–18 atomic planes) could be described by the McWhorter model. Our results indicate that the channel thickness optimization is crucial for practical applications of MoS2 TFTs.
Challenges of Establishing Trust in Online Entities and Beyond

In today's Internet, authenticating online entities is challenging since people lack the real-world cues upon which to base their context-dependent trust decisions. For example, how can a user confirm that a Facebook invitation truly originates from the claimed sender, as anyone can trivially set up a bogus online identity with someone else's photo? Given an SSL certificate warning, how can a user validate it be- fore proceeding, as the certificate could be legitimate (e.g., the certificate is signed by a legitimate authority that the browser does not recognize) or malicious (e.g., it is signed by a compromised CA)? This talk demonstrates that providing useful evidence can empower users to make informed context-dependent trust decisions regarding previously unknown entities in the context of identity and public-key authentication. We first introduce an identity authentication logic called RelationGram that visualizes interpersonal tie strength of virtual entities using both physical and social proximities [2,4]. RelationGram enables casual users to authenticate online identities in a safe and easy manner, and build trust in previously unknown online entities. We then introduce new public-key validation proposals called Accountable Key Infrastructure (AKI) [3] and Attack Resilient Public-Key Infrastructure (ARPKI) [1] that reduce the amount of trust in any single entity to improve the resilience of the current PKI systems. AKI and ARPKI support trust agility such that entities select a security policy for their public-key certificates, and checks and balances such that entities monitor each other for misbehavior and prevent a single point of failure. When users are given pieces of evidence to which they can easily relate, they can make context-dependent authentication decisions online and build trust in online entities. As concluding remarks, we highlight some of the remaining challenges and future research directions to truly empower users to make informed trust decisions.
Improved fusing infrared and electro-optic signals for high-resolution night images

Electro-optic (EO) images exhibit the properties of high resolution and low noise level, while it is a challenge to distinguish objects with infrared (IR), especially for objects with similar temperatures. In earlier work, we proposed a novel framework for IR image enhancement based on the information (e.g., edge) from EO images. Our framework superimposed the detected edges of the EO image with the corresponding transformed IR image. Obviously, this framework resulted in better resolution IR images that help distinguish objects at night. For our IR image system, we used the theoretical point spread function (PSF) proposed by Russell C. Hardie et al., which is composed of the modulation transfer function (MTF) of a uniform detector array and the incoherent optical transfer function (OTF) of diffraction-limited optics. In addition, we designed an inverse filter based on the proposed PSF to transform the IR image. In this paper, blending the detected edge of the EO image with the corresponding transformed IR image and the original IR image is the principal idea for improving the previous framework. This improved framework requires four main steps: (1) inverse filter-based IR image transformation, (2) image edge detection, (3) images registration, and (4) blending of the corresponding images. Simulation results show that blended IR images have better quality over the superimposed images that were generated under the previous framework. Based on the same steps, the simulation result shows a blended IR image of better quality when only the original IR image is available.
Third-Born-approximation effects in electron capture.

We have calculated corrections to the strong-potential Born approximation using the distorted-wave Born formalism of Taulbjerg and Briggs. In the sense of a plane-wave Born expansion, all terms of the third Born approximation, and all ``single switching'' fourth Born terms are included, but a peaking approximation is needed to reduce the calculation to tractable form. We believe this to be the first calculation to be so complete in the Born sense. Effects of the higher terms are most visible in the valley between the Thomas peak and the forward peak. The Thomas peak is visible in the correction term even though it includes no second Born contributions. We suggest that this may be interpreted as a third Born effect with two ``hard'' collisions followed by a ``soft'' collision.
Three-phonon scattering processes and their role in phonon thermal conductivity of silicon

Abstract The true temperature exponents of three-phonon scattering processes for silicon in the temperature range 5–1200°K have been calculated. These values have been used to explain the temperature dependence of phonon thermal conductivity. The theoretically obtained values agree very well with the experimental values. The contributions of transverse and longitudinal phonons toward thermal conductivity of undoped silicon have been investigated, both in high as well as low temperature regions. It is observed that the transverse phonons make a major contribution toward phonon thermal conductivity in the entire temperature range.
A gaze-contingent display to study contrast sensitivity under natural viewing conditions

Contrast sensitivity has been extensively studied over the last decades and there are well-established models of early vision that were derived by presenting the visual system with synthetic stimuli such as sine-wave gratings near threshold contrasts. Natural scenes, however, contain a much wider distribution of orientations, spatial frequencies, and both luminance and contrast values. Furthermore, humans typically move their eyes two to three times per second under natural viewing conditions, but most laboratory experiments require subjects to maintain central fixation. We here describe a gaze-contingent display capable of performing real-time contrast modulations of video in retinal coordinates, thus allowing us to study contrast sensitivity when dynamically viewing dynamic scenes. Our system is based on a Laplacian pyramid for each frame that efficiently represents individual frequency bands. Each output pixel is then computed as a locally weighted sum of pyramid levels to introduce local contrast changes as a function of gaze. Our GPU implementation achieves real-time performance with more than 100 fps on high-resolution video (1920 by 1080 pixels) and a synthesis latency of only 1.5ms. Psychophysical data show that contrast sensitivity is greatly decreased in natural videos and under dynamic viewing conditions. Synthetic stimuli therefore only poorly characterize natural vision.
Institutional investors and the limits of arbitrage

Abstract The returns and stock holdings of institutional investors from 1980 to 2007 provide little evidence of stock-picking skill. Institutions as a whole closely mimic the market portfolio, with pre-cost returns that have nearly perfect correlation with the value-weighted index and an insignificant CAPM alpha of 0.08% quarterly. Institutions also show little tendency to bet on any of the main characteristics known to predict stock returns, such as book-to-market, momentum, or accruals. While particular groups of institutions have modest stock-picking skill relative to the CAPM, their performance is almost entirely explained by the book-to-market and momentum effects in returns. Further, no group holds a portfolio that deviates efficiently from the market portfolio.
Syntactic Features of the Syrohexapla of Ezekiel

An analysis of syntactic features found in the Syrohexapla of Ezekiel in comparison to the Peshitta, on the one hand, demonstrates diachronic development within the Syriac language, and in comparison to the Greek, on the other hand, proves that the Syrohexapla translation was made for scholarly purposes, not for congregational use.
Commensalism or mutualism: Attraction of a sea star towards its symbiotic polychaete

Abstract The sea star, Dermasterias imbricata (Grube), was chemically attracted to its symbiotic scaleworm, Arctonoe vittata (Grube), in a Y-choice apparatus. The sea star consistently chose its symbiont over food, other Dermasterias sp., and Arctonoe fragilis . The specificity and regularity of the response suggest that the host, as well as the symbiont, may benefit from the association.
Water stress effects on root exudation by lodgepole pine

Abstract Individual roots of a 7-year-old lodgepole pine (Pinus contorta Dougl. ex Loud) were subjected to water potentials of 0, −200 or −400 kPa using PEG 4000 as the osmotic agent. Root exudation of photoassimilated 14CO2 was followed over time. Although roots subjected to a water potential of −400 kPa exuded more 14C-labeled material than roots at either 0 or −200 kPa, more labeled material was also translocated to these roots, suggesting an attempt to alleviate the water stress. Some roots exuded over 80% of the total 14C-activity which moved to the roots in 10 days. Although exudation did not appear to be influenced by mycorrhizal infection, mother roots exuded a greater proportion of 14C-labeled assimilates than lateral roots.
Inference About the Masking Probabilities in the Competing Risks Model

The competing risks model considers the setting where a subject or unit is exposed to multiple risks and a failure can be caused by one of the multiple risks. When the causes of failure for an item is not precisely known but can be narrowed down to a subset of the potential risks, the cause is reported as masked. The likelihood model for a masked failure includes the masking probabilities as the chance of the cause getting masked may actually depend on the true cause of failure. This article investigates issues related to statistical inference for the masking probabilities. In terms of predicting the actual but unknown cause of failure of a masked case, the performance of model based prediction is found to be less than desirable in a limited study.
Potentiation of acetazolamide induced ectrodactyly in wistar rats by vasoactive agents and physical clamping of the uterus

The vasoactive agents serotonin, ergotamine, and nicotine potentiate acetazolamide induced forelimb ectrodactyly (missing digits) in Wistar rats. These vasoactive agents administered alone do not produce forelimb ectrodactyly and are not known to be inhibitors of carbonic anhydrase. Additionally, physical clamping of the uterine horns in addition to oral acetazolamide administration increases the frequency of forelimb ectrodactyly, suggesting that decreased uterine blood flow can potentiate acetazolamide teratogenesis. Since the vasoactive agents used in this study are reported to possess uterine vasoconstrictive activity, a decrease in uterine blood flow is a plausible mechanism for the potentiative ability of these agents.
Rapid Clearance of Sialylated Glycoproteins by the Asialoglycoprotein Receptor

The asialoglycoprotein-receptor (ASGP-R) located on liver parenchymal cells was originally identified and characterized on the basis of its ability to bind glycoproteins bearing terminal galactose (Gal) or N-acetylgalactosamine (GalNAc); however, endogenous ligands for the ASGP-R have not to date been definitively identified. We have determined that the rat ASGP-R specifically binds oligosaccharides terminating with the sequence Siaα2,6GalNAcβ1,4GlcNAcβ1,2Man. Bovine serum albumin chemically modified with 10–15 tetrasaccharides with the sequence Siaα2,6GalNAcβ1,4GlcNAcβ1,2Man is cleared from the blood of the rat with a half-life of
An e.s.r. investigation of environmental effects on polymeric materials: 2. Polyethylene

This paper reports results on the effect of various environments, O3, NOx, SO2, u.v. irradiation, combined with stress on the mechanical degradation of polyethylene. Mechanical strength, toughness, free radical production and changes in molecular weight are reported as functions of the ageing time in these environments and at sustained strains corresponding to as much as 90% of the fracture stress for the oriented material and corresponding to the onset of necking in the unoriented material. The results are compared to those previously reported for nylon and discussed in terms of possible molecular mechanisms active during polymer fracture.
Using the wired internet as a control channel for residential wireless LANs

This paper explores the possibility of using the Internet as a control channel for residential wireless networks (RWLANs). We design and implement Telegram, an architecture in which nearby APs coordinate their wireless transmissions over the wired Internet. The latency of coordination is resolved by scheduling packets slightly in advance. Testbed experiments show consistent performance gains, not only due to reduced control traffic, but also due to TDMA-like scheduling in space and time. Motivated by early results, ongoing work is focused on developing a fully-functional system solution.
Adaptation of Impression Cytology to Enable Conjunctival Surface Cell Transcriptome Analysis

AbstractPurpose: This study investigates the extent of the human transcriptome that can be quantified from conjunctival impression cytology extracts. The aim is to determine if sufficient RNA can be isolated from a patient’s conjunctival surface to identify differences in gene expression between dry eye and normal patients of (a) an array of 96 inflammatory biomarkers and associated receptors, and (b) if this comparison can be expanded to the entire transcriptome.Materials and Methods: CIC was used to collect conjunctival surface cells from 53 qualifying normal and dry eye patients. Based on prior optimization of all assay steps, RNA was isolated from the samples using a Qiagen RNeasy Plus Mini Kit and qRT-PCR was used to determine gene expression of 96 genes using TaqMan Low Density Array cards. Samples from six normal and six dry eye patients were then assayed on an Illumina Human HT-12 BeadChip.Results: Optimization steps yielded an RNA processing procedure that improved yield from an initial 12 genes ...
Psychometric properties of scores on three Black racial identity scales.

In this study, we examined the internal consistency and the structural validity of scores on the African Self-Consciousness Scale (ASCS), the Multidimensional Inventory of Black Identity (MIBI), and the Cross Racial Identity Scale (CRIS). Participants consisted of 225 African American college students—75 attending predominantly White institutions (PWIs) and 150 attending historically Black colleges and universities (HBCUs). Internal consistency estimates were above .60 for scores on one ASCS subscale, six MIBI subscales, and six CRIS subscales. Exploratory factor analytic procedures supported a two-factor structure for ASCS scores, a five-factor structure for MIBI scores, and a six-factor structure for CRIS scores. Implications for Black racial identity and scale development are discussed.
Cloning, localization, and permanent expression of a Drosophila octopamine receptor

A cDNA for a member of the G protein-coupled receptor family was isolated from Drosophila using a probe derived from a human β2-adrenergic receptor cDNA. This Drosophila receptor gene is localized at 99A10-B1 on the right arm of chromosome 3 and is preferentially expressed in Drosophila heads. The insect octopamine receptor has been permanently expressed in mammalian cells, where it mediates the attenuation of adenylate cyclase activity and exhibits a pharmacological profile consistent with an octopamine type 1 receptor. Sequence and pharmacological comparisons indicate that the octopamine receptor is unique but closely related to mammalian adrenergic receptors, perhaps as an evolutionary precursor.
Two-dimensional magnetotelluric inversion of blocky geoelectrical structures

[1] This paper demonstrates that there are alternative approaches to the magnetotelluric (MT) inverse problem solution based on different types of geoelectrical models. The traditional approach uses smooth models to describe the conductivity distribution in underground formations. In this paper, we present a new approach, based on approximating the geology by models with blocky conductivity structures. We can select one or another class of inverse models by choosing between different stabilizing functionals in the regularization method. The final decision, whose approach may be used for the specific MT data set, is made on the basis of available geological information. This paper describes a new way of stabilizing two-dimensional MT inversion using a minimum support functional and shows the improvement that it provides over traditional methods for geoelectrical models with blocky structures. The new method is applied to MT data collected for crustal imaging in the Carrizo Plain in California and to MT data collected for mining exploration by INCO Exploration.
EFFECTS OF WELL CASING ON POTENTIAL FIELD MEASUREMENTS USING DOWNHOLE CURRENT SOURCES1

A mathematical formulation for the electric potential from point current-sources coaxial with a metal casing has been obtained. The excitation caused by the axial point-sources will produce currents in the pipe. By assuming that the pipe can be divided into many cylindrical ring segments with constant axially-directed current, the solution of the fields inside and outside the pipe can be formulated in an integral form. The integral equation applied to the segmented pipe yields a set of simultaneous linear equations which are solved for the currents in the pipe; these are then used to calculate the potentials anywhere outside the pipe in the medium. This solution has been used to study the distribution of the potentials in a half-space for a single current-source at and beyond the bottom of a finite length of casing. For a casing 0.1 m in radius and 0.006 m in wall thickness with a conductivity of 106 S/m, in a half-space of 10-2 S/m, it was found that only in a region very near the pipe does the pipe exert substantial influence on the fields of a point-source 100 casing diameters beyond the end of the pipe. It appears that cross-hole resistivity surveys can be implemented without corrections for the casing if the source is located at least 50–100 casing diameters beyond the end of the casing. Hole-to-surface surveys are much more affected by the pipe. For a pipe-source separation of 100 casing diameters, the surface measurements must not be closer than a half pipe length for a 5% or less field distortion.
Organ-derived coatings on electrospun nanofibers as ex vivo microenvironments.

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by irreversible scarring. Collagen deposition, myofibroblast expansion, and the development of fibroblastic foci are the hallmark pathological events. The origin and mechanism of recruitment of myofibroblasts, the key cell contributing to these events, is unknown. We hypothesize that the fibrotic lung microenvironment causes differentiation of arriving bone marrow-derived cells into myofibroblasts. Therefore, a method of isolating the effects of fibrotic microenvironment components on various cell types was developed. Electrospun nanofibers were coated with lung extracts from fibrotic or non-fibrotic mice and used to determine effects on bone marrow cells from naive mice. Varying moduli nanofibers were also employed to determine matrix stiffness effects on these cells. At structured time points, bone marrow cell morphology was recorded and changes in fibrotic gene expression determined by real-time PCR. Cells plated on extracts isolated from fibrotic murine lungs secreted larger amounts of extracellular matrix, adopted a fibroblastic morphology, and exhibited increased myofibroblast gene expression after 8 and 14 days; cells plated on extracts from non-fibrotic lungs did not. Similar results were observed when the nanofiber modulus was increased. This ex vivo system appears to recapitulate the three-dimensional fibrotic lung microenvironment.
A three dimensional serial reconstruction of neuronal distributions in the hypostome of a Hydra.

The numbers, types, and distributions of neurons in a hypostome of Hydra littoralis were determined from electron micrographs of serial (0.25 μm thick) sections. In 1,080 serial sections examined we found 75 sensory cells and 949 centrally located ganglion cells. More than 96% of the 1,024 neurons identified had a single cilium. Sensory cells were most numerous near the apex of the hypostome. Proceeding away from the apex, they steadily decreased in numbers; at 120 μm they were no longer observed. Ganglion cells were bimodally distributed; some were associated with sensory cells at the apex, but most were found at the sites of tentacle origin. We observed, throughout the hypostome, a total of 64 neuronal clusters (three or more contiguous neurons), with an average of five and a maximum of 11 neurons in a cluster. Clusters were distributed similarly to ganglion cells: an initial concentration of clusters near the apex; the majority at the hypostometentacle junctions. Each neuron identified was traced through succeeding sections in which it was observed. We used a three coordinate system to create a three-dimensional reconstruction of the neuronal locations in the hypostome. Although the functional significance of the neuronal distributions we observed is unknown, we suggest that neurons at the apex of the hypostome transduce sensory information involved in feeding behavior. The neuronal concentrations at sites of tentacle origin may be responsible for initiating Contraction Burst Pulses associated with rhythmic behavioral patterns of Hydra or coordinating tentacle movements involved in prey capture, ingestion or locomotion.
MYO-INOSITOL PHOSPHATES IN A PHOSPHOINOSITIDE COMPLEX FROM KIDNEY.

Abstract 1. 1. Chemical studies on the “phosphatido-peptide fraction” from kidney have shown that this material more properly should be called a phosphoinositide complex. 2. 2. Glycerophosphate, inositol mono-, di- and triphosphate were separated from alkaline hydrolysates by means of paper chromatography. 3. 3. Six fractions were obtained by column chromatography from the deacylated phosphoinositide complex and identified as inositol monophosphate, glycerophosphate, inositol diphosphate, glycerylphosphoryl inositol, glycerylphosphoryl inositol phosphate, and glycerylphosphoryl inositol diphosphate. 4. 4. These phosphates, presumably as the inositides, are believed to be responsible for the hgh metabolic activity of this fraction as measured by radiophosphorus.
Transform-domain penalized-likelihood filtering of tomographic data

We present motivation for performing the filtering step of the widely used filtered back-projection algorithm in a non-Radon domain. For square-error optimal penalized-likelihood regularization, filtering in a domain for which the true projection data is sparse in the angle dimension yields coefficients that are more faithful to the ideal filtered data than directly filtering the observed Radon-domain data. In contrast to traditional regularization techniques that filter each projection independently, the proposed filtering technique delivers improved reconstructions by exploiting the correlation of the data in the angle dimension. This enables meaningful reconstructions to be created even from very noisy projection data. In addition, this approach allows for simple penalty matrices to be constructed, enables penalty coefficient to be calculated in a straightforward manner, and results in an easily computed, closed-form solution for the regularizing filters. © 2008 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 18, 350–364, 2008
Ab initio versus CNDO potential surface calculations for Li 2 O and Al 2 O

Potential surfaces for Li2O and Al2O have been calculated by an ab initio SCF-LCAO-MO method and by the semiempirical CNDO method. For both molecules the semiempirical methods incorrectly imply unreasonable structures with very acute apex angles and very long bond distances — rather more like diatomic Li2 or Al2 molecules with O-atoms attached to their bonds. Our ab initio treatment does correctly predict a symmetrical linear configuration for Li2O with bond distances in excellent agreement with experiment. This method also predicts a linear symmetrical structure for Al2O, in agreement with experimental gas phase measurements but in disagreement with matrix-isolation studies.
Surgical Dislocation in the Management of Pediatric and Adolescent Hip Deformity

The surgical dislocation approach is useful in assessing and treating proximal femoral hip deformities commonly due to pediatric conditions. We sought to demonstrate the efficacy and problems associated with this technique. Diagnoses included slipped capital femoral epiphysis, Perthes disease, developmental dysplasia of the hip, osteonecrosis, and exostoses. Through this approach, femoral head-neck osteoplasty (22), intertrochanteric osteotomy (eight), femoral head-neck osteoplasty plus intertrochanteric osteotomy (15), femoral neck osteotomy (five), open reduction and internal fixation of an acute slipped capital femoral epiphysis with callus resection (five), open reduction and internal fixation of an acetabular fracture (one), trapdoor procedure (one), and acetabular rim osteoplasty (one) were performed. The average patient age was 16 years. The minimum followup was 12 months (average, 41.6 months; range, 12-73 months). Patients with Perthes disease and SCFE had preoperative and postoperative WOMAC scores of 9.6 and 5.1, and 7.9 and 3.5 respectively. In patients with unstable SCFEs, the average postoperative WOMAC score was 1.2. Seven patients underwent THAs and two patients underwent hip fusion. Complications in the 58 procedures included four cases of osteonecrosis: three after femoral neck osteotomy and one after intertrochanteric osteotomy. The surgical dislocation technique can be utilized to effectively treat these deformities and improve short-term symptoms. Although the technique is demanding, we believe surgical dislocation offers sufficient advantages in assessing and treating these complex deformities that it justifies judicious application.
Mitotic Motors: Kinesin-5 Takes a Brake

A kinesin-5-dependent 'sliding filament' mechanism is commonly used to actively push apart the poles during mitotic spindle assembly and elongation, but a recent study now shows that, in C. elegans, kinesin-5 is deployed as a brake to slow down spindle-pole separation.
The control of proliferation and differentiation of early erythroid progenitors

Adult erythropoiesis is a continuous process which involves a hierarchy of marrow cellular compartments: stem cells, erythroid progenitors and differentiated precursors [ 1, 2]. Stem cells are recognized by their ability to reconstitute hematopoiesis when injected into lethally irradiated immunohistocompatible recipients. Progenitor cells are defined by their capacity in vitro to give rise to clonal colonies composed of differentiated precursors. The most differentiated precursors are recognized by their morphology. The erythroid progenitors have been divided into late (colony-forming unit, erythroid, CFU-E) and early (burst-forming unit, erythroid, BFU-E) progenitors, which give rise to small (8-30 cells) or large (at least 200 cells) erythroid colonies, respectively [3]. From experiments of colony transplantation into secondary cultures, it has been proved that BFU-E will give rise to CFU-E after a few divisions. This process, usually summarized with an arrow going from a circle representing the BFU-E to another circle representing the CFU-E, is complicated. It involves at least 6-10 cell divisions. After each division, the daughter cells are slightly different from the preceding cells in terms of proliferative potential and the expression of the erythroid differentiation program. Consequently, at least two partially different regulation programs must be involved in each cell cycle: one program controls proliferation and leads to DNA duplication, and the other progressively switches off genes which allow future divisions while switching on genes related to lineage-specific differentiation. This last regulation program is based on proper DNA-protein interactions and involves reassembling of the nucleosomes, modification of the DNA methylation sites and activation of the expression of lineage-specific transcription factors. It is obvious that this complex series of intracellular events is tightly regulated by external factors either because these factors are required to trigger these events [4] or because these factors allow the survival only of such cells in which the proper intracellular events have occurred [5]. This review summarizes what is known at the present about the growth factors involved in the control of the early phases of erythroid proliferation and differentiation.
Veratrum Alkaloids XXXII *: The Structures of Germitetrine and Some Related Hypotensive Ester Alkaloids

The structures of germitetrine and several related hypotensive esters of germine have been elucidated. The chemically-related series germitetrine, desacetylgermitetrine, and neogermbudine are formulated as I, IV, and V, respectively.
Pattern triplications produced by a cell-lethal mutation in Drosophila.

Abstract A 48-h 29°C treatment given to larvae homo- or hemizygous for a ts cell-lethal mutation often results in pattern triplications of leg structures. The extra sets of structures are located in discrete cuticular processes and always obey W. Bateson's rule (1894, “Materials for the study of Variation,” Macmillan, London) . These processes may become more circumferentially complete distally (diverge) or less complete (converge) by the addition or deletion of pattern elements at the lines of symmetry between the two sets of structures. Analysis of the location of the cuticular processes in the leg suggests that convergence and divergence may depend on the circumferential location of the cuticular process. The results are discussed in light of the predictions of the polar coordinate model of positional information (S. V. Bryant, V. French, and P. J. Bryant, 1981) which can explain most, but not all, of the observations.
Neovesical-urethral anastomotic stricture after orthotopic urinary diversion : presentation and management

OBJECTIVE To assess the frequency, presentation, treatment, and outcomes of bladder neck contractures (BNCs) among patients who had an orthotopic urinary diversion after radical cystectomy. PATIENTS AND METHODS We retrospectively examined our single-institution database of 788 patients who had a radical cystectomy from 1 January 1996 to 4 January 2006 for BNC; variables evaluated included presentation, degree of stricture/contracture, clinical management, and outcomes after management. RESULTS Of the 374 patients who had an orthotopic urinary diversion, 11 (2.9%) men developed BNC; four BNCs were between 17 F and 22 F, six were <17 F, and one was pinhole-sized. Nine of the 11 patients presented with voiding difficulties, one in complete retention after complicated urinary tract infection, and one with new-onset nocturnal urinary incontinence. The treatment of BNC included cystoscopic dilatation in the clinic in six and under anaesthesia in three, and transurethral incision with a Collins knife or holmium laser in seven. After treatment, all patients were instructed to use continuous intermittent catheterization (CIC). Ten patients had follow-up data available after the intervention, with a mean (range) follow-up of 40.6 (10.6–98.0) months. Six patients were stricture- free for a mean period of 35.4 (10.6–98.0) months, while four patients had a recurrence within a mean of 7.4 (1.3–17.1) months. At the last follow-up, nine of the 10 patients were using CIC. No patient had significant daytime or night-time incontinence after treatment. CONCLUSION BNC develops in a small proportion of patients undergoing orthotopic urinary diversion, with most patients presenting with voiding difficulty. Most will require transurethral incision rather than an office-based dilatation. After endoscopic incision to correct BNC, we recommend CIC to ensure complete emptying and to maintain the patency of the anastomotic stricture.
Feasibility of Ultrasound-Guided Percutaneous Placement of Peripheral Nerve Stimulation Electrodes in a Cadaver Model: Part One, Lower Extremity

Background and Objectives: Peripheral nerve stimulation (PNS) is analgesic for some lower extremity neuropathic pain syndromes. PNS currently involves open surgical placement of electrode(s). Increasingly, ultrasound guidance is used for perioperative neural block. Minimally invasive placement of PNS electrodes for lower extremity targets using ultrasound guidance has not been reported. We hypothesized that ultrasound-guided placement of PNS electrodes was feasible. Methods: Four cadaver mid-thigh transected fresh frozen specimens were studied. Specimens were scanned utilizing a 14 to 7 MHz linear probe and electrodes were placed proximal to the tibial, peroneal, and sciatic nerves at various locations. Anatomical dissection was performed to check placement accuracy and evaluate for grossly visible neural injuries. Results: Acceptable locations for ultrasound-guided electrode placement were: (1) tibial nerve, approximately 8 to 14 cm superior to the medial malleolus above the tarsal tunnel, or at the upper popliteal fossa; (2) peroneal nerve, approximately 2 to 4 cm inferior to the lateral fibular head or at the upper popliteal fossa; (3) sciatic nerve immediately superior to the bifurcation (high popliteal area); and (4) lateral sural nerve at the lower popliteal fossa. No grossly visible neural injuries were seen. Electrode placements appeared to be in satisfactory locations for stimulation. Conclusions: Ultrasound imaging to facilitate peripheral nerve electrode placement is feasible. This new minimally invasive approach to lead placement requires further study to determine trial implantation criteria, optimal locations, anchoring techniques, and best clinical practice.
Eye-head coordination during postural perturbation as a predictor of falls in community-dwelling elderly women

Abstract Di Fabio RP, Greany JF, Emasithi A, Wyman JF. Eye-head coordination during postural perturbation as a predictor of falls in community-dwelling elderly women. Arch Phys Med Rehabil 2002;83:942-51. Objectives: To assess the functional significance of eye-head coordination during postural perturbations and to determine the contribution of angular vestibulo-ocular reflex (AVOR) suppression to the prediction of 1-year fall history in community-dwelling elderly women. Design: Descriptive analysis of factors correlated with falls. Setting: Community-based independent and senior assisted living facilities. Participants: Volunteer sample of 38 older women (mean age ± standard deviation, 81.6±3.9y; range, 74–92y). Interventions: Not applicable. Main Outcome Measures: Multiple and logistic regression variables (slope coefficients, partial R 2 , percent-correct fall history classifications) and fall prediction equations generated by using minimal sets of predictor variables. Results: Instantaneous AVOR gain and sedative use were predictors of 1-year history of falls in all minimal sets of predictor variables. R 2 for the prediction models varied from .47 to .62 and indicated substantial shared variance with the 1-year history of falling. Elderly women who failed to suppress the AVOR gain were 18 times more likely to have experienced a fall in the past year compared with elderly women who showed AVOR suppression (odds ratio=18; 95% confidence interval, 1.63–198.42). Conclusions: When controlling for all other variables in the model, instantaneous AVOR gain accounted for nearly 30% of the variance of fall history. The strong association between 1-year fall history, the use of sedatives, and changes in the AVOR gain supports a functional link between AVOR suppression and effective balance in elderly women. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation
Dopamine and the Aged

: Regardless of the age of the patient, dopamine is a valuable agent for treating shock associated with an abdominal catastrophe. However, when the time is appropriate for withdrawal of dopamine, the aged do not react as do younger patients. Despite apparent adequate hydration, additional volume loading is required to avert renal failure, and the dosage of dopamine has to be decreased gradually until withdrawal is complete.
MARKETING JOURNALS READERSHIP STUDY

Introduction How thoroughly do practitioners read marketing journals? For most marketing journals, practitioner subscribers represent the largest and therefore the most important potential readership segment. As others have noted, unless a journal is read, its effectiveness is minimized regardless of the esteem with which it is held.
Stoichiometry of BkdR to substrate DNA in Pseudomonas putida.

Abstract BkdR is the transcriptional activator of the bkd operon of Pseudomonas putida, which encodes branched chain keto acid dehydrogenase. BkdR binds to a large region of DNA between its own structural gene and the first gene of the bkd operon. The object of the present studies was to determine the stoichiometry of binding as part of an effort to understand the action of BkdR in regulation of the bkd operon. [ 35 S]BkdR was prepared and found to be essentially 100% active in the gel shift assay. Only one complex was formed under all the conditions used. The stoichiometry of BkdR binding to its specific substrate DNA was three tetramers per mole substrate DNA. L-valine did not affect the stoichiometry although this ligand was previously shown to affect the DNase I protection pattern. The addition of nonspecific DNA to the incubation mixture also did not affect this stoichiometry.
Simulation of flow problems with moving mechanical components, fluid–structure interactions and two‐fluid interfaces

The application of a stabilized space-time finite element formulation to problems involving fluid-structure interactions and two-fluid interfaces is discussed. Two sample problems are presented and the method is validated by comparison with a test problem.
An analysis of binaural spectro-temporal masking as nonlinear beamforming

Array-based time-frequency masking algorithms are an important type of nonlinear array processing. In this paper we develop a model that characterizes the directional sensitivity of these algorithms in a fashion similar to commonly-used the beam patterns used to characterize linear array processing. Two alternative formulations are described, and it is shown that one of these formulations predicts signal distortion and processing gain in time-frequency masking accurately, as well as speech recognition accuracy afforded by time-frequency masking in the presence of additive interfering sources.
Web mining from competitors' websites

This paper presents a framework for user-oriented text mining. It is then illustrated with an example of discovering knowledge from competitors' websites. The knowledge to be discovered is in the form of association rules. A user's background knowledge is represented as a concept hierarchy developed from documents on his/her own website. The concept hierarchy captures the semantic usage of words and relationships among words in background documents. Association rules are identified among the noun phrases extracted from documents on competitors' websites. The interestingness measure, i.e. novelty, which measures the semantic distance between the antecedent and the consequent of a rule in the background knowledge, is computed from the co-occurrence frequency of words and the connection lengths among words in the concept hierarchy. A user evaluation of the novelty of discovered rules demonstrates that the correlation between the algorithm and the human judges is comparable to that between human judges.
REPLACING POINTS BY COMPACTA IN NEURAL NETWORK APPROXIMATION

It is shown that cartesian product and pointwise-sum with a fixed compact set preserve various approximation-theoretic properties. Results for pointwise-sum are proved for F-spaces and so hold for any normed linear space, while the other results hold in general metric spaces. Applications are given to approximation of Lp-functions on the d-dimensional cube, 1⩽p<∞, by linear combinations of half-space characteristic functions; i.e., by Heaviside perceptron networks.
Clarification of some misconceptions about antidune geometry and flow character

Estimates of palaeoflow conditions based on antidune geometries generally are obtained using equations derived from potential flow analysis. Unfortunately, in several previous studies and review articles, misunderstanding and improper substitution of density terms has resulted in two misconceptions (a third is discussed in detail elsewhere). Both concern the commonly derived ratio of antidune wavelength to critical flow depth (L/D). Previously published results which suggest that, for a given set of flow conditions in a two-layer system, L/D increases with increasing density contrast (Δρ) are wrong. Correct substitutions indicate the opposite—there is a slightly inverse relationship between the value of L/D and Δρ. The second misconception concerns the two values reported for critical flows: L/D≥ 6·3 (or ≥ 2γ) and L/D≥ 12·6 (or ≥ 4γ). Despite insinuations that the latter is wrong by a factor of two, both are correct. In this case, what has been overlooked is that the former value is derived for antidunes on free surface flows (a ‘two-layer’ system in which ρ2 << ρ1) and the latter for antidunes at the interface of a two-layer system in which Δp→0 (i.e. ρ2SIMEρ1).
Individual cartilage aggrecan macromolecules and their constituent glycosaminoglycans visualized via atomic force microscopy

Abstract Atomic force microscopy was used in ambient conditions to directly image dense and sparse monolayers of bovine fetal epiphyseal and mature nasal cartilage aggrecan macromolecules adsorbed on mica substrates. Distinct resolution of the non-glycosylated N-terminal region from the glycosaminoglycan (GAG) brush of individual aggrecan monomers was achieved, as well as nanometer-scale resolution of individual GAG chain conformation and spacing. Fetal aggrecan core protein trace length (398 ± 57 nm) and end-to-end length (257 ± 87 nm) were both larger than that of mature aggrecan (352 ± 88 and 226 ± 81 nm, respectively). Similarly, fetal aggrecan GAG chain trace length (41 ± 7 nm) and end-to-end (32 ± 8 nm) length were both larger than that of mature aggrecan GAG (32 ± 5 and 26 ± 7 nm, respectively). GAG–GAG spacing along the core protein was significantly smaller in fetal compared to mature aggrecan (3.2 ± 0.8 and 4.4 ± 1.2 nm, respectively). Together, these differences between the two aggrecan types were likely responsible for the greater persistence length of the fetal aggrecan (110 nm) compared to mature aggrecan (82 nm) calculated using the worm-like chain model. Measured dimensions and polymer statistical analyses were used in conjunction with the results of Western analyses, chromatographic, and carbohydrate electrophoresis measurements to better understand the dependence of aggrecan structure and properties on its constituent GAG chains.
Relationships as regulators.

This paper reviews the Hofer (1984, 1996) and Field (1985, 1994) models on relationships as regulators, suggesting that relationships regulate optimal stimulation and thereby modulate arousal levels and attenuate stress. In these models, the behavioral, physiological and biochemical rhythms of individuals become synchronized within close relationships like mother-infant and peer relationships both in human and animal species, and they become more coordinated over time, with some potentially remaining stable, much like zeitgebers. Hofer supports his model by data on infant rat separation stress and Field describes “psychobiological attunement” between human infants and their mothers and between young peers. This review revisits the “relationships as regulators” model, summarizing studies on relationships between non-depressed versus depressed mothers and their infants, between infant, preschool and preadolescent friends versus acquaintances and between happily versus unhappily married couples. Although some behavioral and physiological data support Hofer’s and Field’s “relationships as regulators” model, many studies on relationships have focused instead on the effects of separation or loss. Both Hofer and Field suggest that the real question is “what was there about the relationship that was then missing after the loss?” Future research could address the question of potential mediators and underlying mechanisms for relationships becoming regulators. Potential mediators are explored here including mirror neurons, affective priming, imitation and empathy. The individuals’ rhythms and the attraction to others’ rhythms as regulators may be an epigenetic programming phenomenon, suggesting both genetic and early experience effects that endure across development.