cssi/SciSciGPT-SciSciNet huggingface dataset:
Interactive Computer Display for the Three Dimensional Study of Macromolecular Structures

THE application of real-time, three dimensional computer graphics to molecular structure studies has been limited so far to rather expensive, dedicated computer display devices1,2 or to fairly simple structures. The frequently used display device has been a black-and-white cathode ray tube3 with a split image or rotating image. This communication discusses the application of a colour television monitor to macromolecular modelling. Even with a small, 4,096 word laboratory computer driving the graphics display, it is now possible to view three dimensional models of large portions of macromolecular structures determined by X-ray diffraction studies. I am now assembling a library of protein structures for three dimensional display in conjunction with the Department of Chemistry, Brookhaven National Laboratory, for educational and research purposes.
Corrigenda to “The Sine-Gordon Equation in the Semiclassical Limit: Critical Behavior Near a Separatrix”

Figure 1.6. The contour N of discontinuity for the sectionally analytic function N(w). With the exception of the two components of R+ \ I which are oriented leftto-right, the contour arcs are oriented with the regions labeled “+” on the left and with the regions labeled “−” on the right. The image of N \R+ under w → E(w) with E defined by (1.10) consists of the four straight line segments: (i) {E} = −δ , 0 0 is a sufficiently small number. The self-intersection point w = −1 is the critical point of E .
The NFY transcription factor inhibits von Willebrand factor promoter activation in non-endothelial cells through recruitment of histone deacetylases

Human von Willebrand factor (VWF) gene sequences +155 to +247 contain cis-acting elements that contribute toward endothelial specific activation of the VWF promoter. Analyses of this region demonstrated the presence of a GATA-binding site that is necessary for the promoter activation in endothelial cells. We have reported recently the presence of a novel NFY-binding sequence in this region that does not conform to the consensus NFY-binding sequence CCAAT. NFY was shown to function as a repressor of the VWF promoter through interaction with this novel binding site. Here we report that the NFY interacts with histone deacetylases (HDACs) in a cell type-specific manner and recruits them to the VWF promoter to inhibit the promoter activity in non-endothelial cells. Analyses of the acetylation status of histones in the chromatin region containing the VWF promoter sequences demonstrated that these sequences are associated with acetylated histone H4 specifically in endothelial cells. It was also demonstrated that HDACs are specifically recruited to the same chromatin region in non-endothelial cells. We also demonstrated that GATA6 is the GATA family member that interacts with the VWF promoter and that GATA6 is associated with NFY specifically in non-endothelial cells. We propose that NFY recruits HDACs to the VWF promoter, which may result in deacetylation of GATA6 as well as of histones in non-endothelial cells, thus leading to promoter inactivation. In endothelial cells, however, association of HDACs, NFY, and GATA6 is interrupted potentially through endothelial cell-specific signaling/mechanism, thus favoring the balance toward acetylation and activation of the VWF promoter.
WITHIN-PLANT VARIATION IN CONCENTRATIONS OF AMINO ACIDS, SUGAR, AND SINIGRIN IN PHLOEM SAP OF BLACK MUSTARD, Brassica nigra (L.) KOCH (CRUCIFERAE)

Although within-plant variation in the nutrient and allelochemical composition of phloem sap has been invoked to explain patterns of host use by phloem-feeding insects, little is known about within-plant variation in phloem chemistry. Here I describe a new technique in which I use the green peach aphid,Myzus persicae Sulz., to investigate within-plant variation in the concentrations of chemicals in the phloem sap of black mustard,Brassica nigra (L.) Koch (Cruciferae). Relationships between the concentrations of chemicals in aphid diets and honeydew were established using honeydew from aphids fed on artificial diets with known concentrations of amino acids, sucrose, and sinigrin. These relationships were applied to honeydew from aphids fed on different aged leaves of black mustard to estimate the concentrations of the chemicals in phloem sap. Sinigrin concentration was estimated to be high (>10 mM) in phloem sap in young leaves, calling into question the prevailing opinion that phloem sap contains only low concentrations of allelochemicals. High concentrations may function as defenses against sap-feeding herbivores. Within-plant variation in phloem sap composition was high: (1) young leaves had high concentrations of nutrients (216 mM amino acids, 26% sugar) and sinigrin (>10 mM); (2) mature and presenescent leaves had lower concentrations of nutrients (77-83 mM amino acids, 19-20% sugar) and low concentrations of sinigrin (1-2 mM); and (3) senescing leaves had high concentrations of nutrients (199 mM amino acids, 25% sugar) and low concentrations of sinigrin (3 mM).
Epinephrine contents of sympathetic ganglia and brain regions of spontaneously hypertensive rats of different ages.

SummaryThe activity of phenylethanolamine N-methyltransferase (PNMT), the enzyme that catalyzes the synthesis of epinephrine from norepinephrine, was higher in a section of the medulla containing nucleus tractus solitarius from a genetic strain of spontaneously hypertensive rats (SHR) than in appropriate Wistar Kyoto (WKY) control rats. The concentration of epinephrine, but not of other catecholamines, was higher in the hypothalamus of SHR. These differences appeared between the fourth and ninth week of life and continued into adulthood. The contents of norepinephrine, dopamine and epinephrine in the superior cervical ganglia of SHR were also higher than in WKY; these differences were first noted at 4 weeks of age. During the first 3 weeks of life, SHR were more sensitive to the dexamethasone-induced increases in both the PNMT activity of the brain and the epinephrine content of the ganglia.
Pair-rule gene expression in the somitic stage chick embryo: association with somite segmentation and border formation

Abstract In vertebrates, metameric organization is highlighted by the formation of somites from mesenchymal cells of the segmental plate which then differentiate into dermamyotomal and sclerotomal tissues. The resegmentation of the sclerotome into rostral and caudal halves follows, coincident with the production of specific extracellular matrix molecules at the abutment of these two cell types. Ultimately, cells from the caudal sclerotome migrate ventrally and contribute to the chondrogenic prevertebrae. The objective of this work is to investigate the molecular steps regulating these events. Our study is focused on the paired-box containing genes, which have been implicated in delineating boundaries early in development. A chick embryo system, which is readily accessible to manipulation and observation during early development, is used in this study. We have identified the existence of the paired-box motif in the chicken genome by polymerase chain reaction and hybridization with the mouse Pax 1 paired-box sequence. Expression of paired-box genes occurs early in development as shown by Northern analysis, and is localized by in situ hybridization to the edge of each somite, a patch at the central core of each somite, and the periphery of the neural tube. This specific spatial pattern of expression is consistent with the hypothesis that the pair-rule genes function as effecters of border formation in the early embryo. Moreover, the patch of positive cells at the center of a resegmenting somite appear to migrate ventrally, and may contribute to structures of the prevertebrae. These findings are relevant to our understanding of the mechanism of somite resegmentation and implicate the involvement of pair-rule genes in the process.
Intracellular Ca2+ and adaptation of voltage responses to light in Hermissenda photoreceptors

FLUORESCENT imaging of Ca 2+ and intracellular recordings were used to assess Ca 2+ increases and voltage responses during light presentations in Hermissenda B photoreceptors. Ca 2+ levels increased and were sustained during a relatively long exposure to light. Repeated presentations of a brief light induced an elevation of intracellular Ca 2+ that persisted throughout short interlight intervals, but which dissipated during long interlight intervals. In all instances, the magnitude of the intracellular Ca 2+ signal was inversely related to the amplitude of the light-induced generator potential. Blocking of voltage-dependent Ca 2+ channels did not significantly affect the magnitude of the Ca 2+ signal, suggesting that the intracellular Ca 2+ response arises primarily from release from intracellular stores. These results indicate that Ca 2+ plays an important role in the modulation of the voltage responses to light, acting to suppress the response during repetitive or prolonged stimulation.
An integrated SIDO boost power converter with adaptive freewheel switching technique

This paper presents a single-inductor dual-output (SIDO) boost DC-DC converter with an adaptive freewheel switching technique. Due to the adoption of freewheel switching duration averaging, the optimal freewheel durations in each phase of the SIDO converter are acquired within one switching cycle. The optimal freewheel switching duration improves the efficiency of the SIDO converter, especially during unbalanced load conditions, by reducing the conduction losses due to the lossy freewheel switch. The proposed controller also accelerates the freewheel switching current adjustment process during the load transient periods. The proposed converter, operating in the pseudo-continuous conduction mode (PCCM), has been verified through fully transistor-based HSPICE simulation results, with a 130-nm CMOS process. It achieves a maximum efficiency of 90.1%, at an output power of 430 mW and a switching frequency of 500 kHz. For a load change from 100 mA to 50 mA, the proposed technique reduces the conduction losses during the freewheel switching duration by 99.52%, compared with the traditional methods.
An Experiment in Physical Chemistry: Polymorphism and Phase Stability in Acetaminophen (Paracetamol)

Differential scanning calorimetry analyses of two easily prepared polymorphs of acetaminophen (also known as paracetamol) are recorded. The density of the forms can be found in the literature. Rules for heats of transition, heats of fusion, and density, as well as methods for determining the solid−solid transition temperature between the forms, are used to determine whether the two forms are enantiotropic or monotropic and to determine which is the more stable form at room temperature and pressure.
The basis for bibliomining: Frameworks for bringing together usage-based data mining and bibliometrics through data warehousing in digital library services

Over the past few years, data mining has moved from corporations to other organizations. This paper looks at the integration of data mining in digital library services. First, bibliomining, or the combination of bibliometrics and data mining techniques to understand library services, is defined and the concept explored. Second, the conceptual frameworks for bibliomining from the viewpoint of the library decision-maker and the library researcher are presented and compared. Finally, a research agenda to resolve many of the common bibliomining issues and to move the field forward in a mindful manner is developed. The result is not only a roadmap for understanding the integration of data mining in digital library services, but also a template for other cross-discipline data mining researchers to follow for systematic exploration in their own subject domains.
Analysis of yggX and gshA Mutants Provides Insights into the Labile Iron Pool in Salmonella enterica

Strains of Salmonella enterica lacking YggX and the cellular reductant glutathione exhibit defects similar to those resulting from iron deficiency and oxidative stress. Mutant strains are sensitive to hydrogen peroxide and superoxide, deregulate the expression of the Fur-regulated gene entB, and fail to grow on succinate medium. Suppression of some yggX gshA mutant phenotypes by the cell-permeable iron chelator deferoxamine allowed the conclusion that increased levels of cellular Fenton chemistry played a role in the growth defects. The data presented are consistent with a scenario in which glutathione acts as a physiological chelator of the labile iron pool and in which YggX acts upstream of the labile iron pool by preventing superoxide toxicity.
Key peptide processing enzymes are expressed by a variant form of small-cell carcinoma of the lung

Abstract Small-cell carcinoma of the lung (SCCL) is a neuroendocrine tumor characterized by having the capacity to produce and secrete a number of small neuropeptides. These peptides serve the tumor as autocrine growth factors. SCCL is known to undergo a process of dedifferentiation to a variant (drug-resistant) form, and this process is associated with loss of marker enzymes such as neuron-specific enolase (NSE) and dopa decarboxylase (DDC). The current study was designed to discover if variant SCCL, represented by cell line NCI H82, retains some capacity to generate active neuropeptides (like vasopressin) from their precursors by continuing to express the three key classes of enzymes necessary for such conversions, namely prohormone convertases (PCs), carboxypeptidases (CPs), and peptidylglycine α-amidating monooxygenase (PAM). RT-PCR for mRNAs representing PC1, PC2, CPE, and PAM was performed on total RNA extracted from NCI H82. The primers selected for PCR and partial sequencing were synthetic 20, 21, 22, and 24 oligomers designed to yield products of 533, 880, 405, and 560 base pairs (bp) for PC1, PC2, CPE, and PAM, respectively. For the conditions used, we were able to demonstrate products for all four enzymes. Each of the four products generated were of the expected size. Cloning and sequencing of these products revealed that each had a structure identical to that published for the human form of the respective enzyme. Western analysis with antibodies against PC1, PC2, CPE, and PAM, provided evidence that mRNAs for the four enzymes are translated into proteins that could represent functional forms. Our findings therefore demonstrate that key enzymes involved in the generation of active neuropeptides, unlike the marker enzymes NSE and DDC, continue to be expressed by variant SCCL.
Determination of a convex body from the average of projections and stability results

Analysis of projections of a convex body is a familiar topic in tomography. However, instead of considering standard projection bodies, this work investigates a convex body introduced by Schneider [8] which is a Minkowski average of projections. The question addressed here is similar to that posed by Goodey and Weil [4] with respect to Minkowski averages of sections, as opposed to projections, that is, can the shape of a convex body be determined from random sections? Their main result shows that a body K is determined by the average of its two-dimensional sections, but not by the average of its one-dimensional sections. The goal of this study is to uncover the extent to which a convex body is determined by the average of its projections.
Biodegradation of benzo[a]pyrene with immobilized laccase: genotoxicity of the products in HaCat and A3 cells.

Benzo[a]pyrene (BaP) is listed as a priority pollutant by the U.S. Environmental Protection Agency because it is one of the most potent carcinogens of all known polycyclic aromatic hydrocarbons (PAHs). The biodegradation of BaP is of interest as a means for mitigating its effects in polluted ecosystems. In the present study, BaP was oxidized with laccase from Trametes versicolor, which was immobilized on functionalized kaolinite particles, and the cytotoxicity and genotoxicity of BaP and its degradation intermediates were measured in human HaCaT keratinocytes and A3 T lymphocytes. Cytotoxicity was assessed by fluorescein diacetate (FDA) uptake, while the alkaline Comet assay measured genotoxicity, using tail moment, tail DNA content, and tail length as metrics for DNA damage. On the basis of first-order reaction kinetics, the half life (t(1/) (2)) for the oxidization of BaP by immobilized laccase was 58.5 hr. After 87 hr of oxidation, 20 muM of BaP had decreased to 9.6 muM. HPLC analysis identified 1,6-benzo[a]pyrene quinone (1,6-BaQ), 3,6-benzo[a]pyrene quinone (3,6-BaQ), and 6,12-benzo[a]pyrene quinone (6,12-BaQ) among the oxidation products. Most treatments of HaCaT cells and A3 lymphocytes with BaP or its quinone intermediates resulted in significant decreases in viability (P 30%. While treatment of HaCaT cells with as little as 0.1 muM 6,12-BaQ caused significant DNA damage, DNA damage was detected in HaCaT cells only with 1 and 5 muM 1,6-BaQ and 3,6-BaQ, and 5 muM BaP. In Comet assays conducted with A3 lymphocytes, all three quinone intermediates caused significant increase in tail DNA content at 1 and 5 muM. The results indicate that immobilized laccase is capable of degrading BaP, but several of those biodegradation products produce significant levels of DNA damage in human cells.
Outcome in infants with pulmonary atresia, intact ventricular septum, and right ventricle–dependent coronary circulation

Management of all patients with pulmonary atresia, intact ventricular septum, and right ventricle-dependent coronary circulation (n = 12) with staged surgery directed toward a Fontan palliation resulted in an 83% 5-year actuarial survival. Both deaths in the study were presumably related to coronary ischemia and occurred in the first 4 months of life.
An approach to manufacturing control using inexpensive source to computer communication

More efficient use of computers to reduce costs as a result of improved scheduling and control of manufacturing operations is made possible through the availability of timely, accurate and complete information.This requires more effective data gathering from the lowest and most dispersed level of operations. Such extensive coverage is made economically feasible through the application of a concept of tailor made systems which provides versatility through the use of a variety of modular subassemblies. Low cost is possible through extensive use of components and devices mass produced for other purposes. Some aspects of two systems which employ these concepts are described.
High Speed Memory Scanning in Parkinsonism

This study tested the hypothesis that the slowing seen in parkinsonism includes cognitive as well as motoric components. The sample consisted of 20 nondemented parkinsonian patients, group matched to 16 normals by age, education, and verbal IQ. Each group was divided into young (64 and under) and old (65 and over) subsets. The Sternberg character classification paradigm was used to measure the speed and accuracy of one cognitive function, short term memory scanning. Following a logarithmic transformation of the reaction time data, scanning speed was found to be increased, but only for the elderly patients (p = .01). Scanning accuracy was normal for both patient groups. These findings suggest that at least one cognitive function, the scanning of elements held in short term memory, is slowed in parkinsonism. This mnemonic slowing, like bradykinesia, is seen primarily in elderly parkinsonian patients. It is not readily explained as a motor phenomenon, as part of a generalized mnemonic or intellectual deficit, or as an artifact secondary to periodic extreme reaction times. The term bradyphrenia, used in early descriptions of parkinsonism, may be an apt descriptor of this deficit.
Stimulation, control and phylogenetic projection of the teleostean yawn reflex

Abstract 1. 1. Yawns were induced in 13–18-kg red snappers (Lutianus aya) and jewfish (Promicrops itaiara) by decreasing the ambinet pressure 12 cm H2O. 2. 2. Sustained depression increased yawn frequency (yawn/45 min to yawn/ 3 min) and evoked other buoyancy reactions like those reported for a 100-g pinfish. 3. 3. Yawns, with swimbladder compression, were elicited in pinfish by unipolar electrical stimulation of the cerebellum. 4. 4. The yawn reflex is a basic teleostean function which persists in each class of vertebrates. 5. 5. The extra-medullary yawn site of teleosts may be the phylogenetic precursor of the pontine “apneustic center” in mammals.
The English language and its teachers: thoughts past, present, and future

This paper derives from a talk given last year in London at the IATEFL Silver Jubilee Seminar. John Swales was among a group of experts invited to consider developments in ELT over the last twenty-five years and predict what might be the issues of the next twenty-five years. His talk focused on the topic of the English language and its teachers, and ranged across a number of key issues: English as a world language, non-native users of English, aspects of language change, developing areas of language study, and the career concerns of the ELT profession.
NAFTA and Mexico's current economic crisis: Short-run and long-run perspectives

Abstract Policy-makers in both Mexico and the U.S. reacted to the economic crisis which began in Mexico in December, 1994 as if it were a problem of short-run financial liquidity. The argument presented in this article is that Mexico's current crisis has its origins in long-standing, fundamental problems of the Mexican economy. These long-run problems include: massive external debt, a severely skewed income distribution, inadequate job creation, low productivity per worker and lack of investment in infrastructure. The short-run policy response will not address the long-run problems.
Error and convergence of two numerical schemes for stochastic differential equations

We examine the convergence and error rate of two stochastic numerical schemes using the method of proof used by G. N. Mil'shtein (Theory Prob Appl 19 (1974), 557–562). © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2006.
Variables Related to Sleep Problems in Children with Autism.

Abstract Our study of 477 children with autism (1–15 years, IQs 9–146) showed that parent reported sleep problems are found in most children with autism and are not significantly related to age, IQ, gender, race, parent occupation, neuropsychological functioning, and learning ability. However, sleep problems increased with severity of autistic symptoms and with severity of parent reported symptoms known to be associated with autism (i.e., oppositional behavior, aggression, explosiveness, attention deficit, impulsivity, hyperactivity, anxiety, depression, and mood variability). This suggests that sleep disturbance is part of the autism symptom complex and increases with increasing autism severity. The strongest predictors of sleep disturbance were parent ratings of autism severity, hyperactivity, mood variability, and aggression. The most frequent sleep problems were difficulty falling asleep and restlessness during sleep. Daytime sleepiness was not significantly correlated with sleeping less than normal, but was associated with sleeping more than normal. Children who were sleepier during the day were also sleepier at night. Medical practitioners and clinicians should be aware of the risk of sleep disturbance in children with autism and should routinely screen for this. Empirically proven interventions (e.g., behavior therapy and melatonin) are available to improve sleep in children with autism.
On energy efficient MIMO-assisted spectrum sharing for cognitive radio networks

We formulate the design of energy efficiency maximization for a single secondary link in an underlay spectrum sharing cognitive radio network under an SU (secondary user) transmit-power constraint and an upperbound on the interference power at the PU (primary user). We propose energy efficient precoding (beamforming) for the SU transmitter to maximize energy efficiency defined as the transmission rate to power ratio, when the terminals in the system are equipped with multiple antennas. The underlying channels are assumed to be known at the SU transmitter. The nonlinear optimization (fractional programming) problem is transformed into a parametrized convex optimization problem and the corresponding solution is discussed. Computer simulation examples are provided to illustrate the proposed approach and to explore the trade-off between energy efficiency and spectrum efficiency.
The three-class ideal observer for univariate normal data: Decision variable and ROC surface properties.

Although a fully general extension of ROC analysis to classification tasks with more than two classes has yet to be developed, the potential benefits to be gained from a practical performance evaluation methodology for classification tasks with three classes have motivated a number of research groups to propose methods based on constrained or simplified observer or data models. Here we consider an ideal observer in a task with underlying data drawn from three univariate normal distributions. We investigate the behavior of the resulting ideal observer’s decision variables and ROC surface. In particular, we show that the pair of ideal observer decision variables is constrained to a parametric curve in two-dimensional likelihood ratio space, and that the decision boundary line segments used by the ideal observer can intersect this curve in at most six places. From this, we further show that the resulting ROC surface has at most four degrees of freedom at any point, and not the five that would be required, in general, for a surface in a six-dimensional space to be non-degenerate. In light of the difficulties we have previously pointed out in generalizing the well-known area under the ROC curve performance metric to tasks with three or more classes, the problem of developing a suitable and fully general performance metric for classification tasks with three or more classes remains unsolved.
The impact of the interconnect delays on a high performance ASIC array

Abstract The importance of the interconnect delays in modern ICs increases since they do not scale proportionally with device delays. This paper presents the main aspects of the ASIC design and development which are influenced by the shift in the time budget of an ASIC due to the metal-delays weight, using a high performance array in a 0.6 μm BiCMOS process as an example.
“We’re All Sisters”: Bridging and Legitimacy in the Women’s Antiprison Movement

Claims to sisterhood are premised on women’s experiences with gender oppression, and many have argued that such claims ignore differences among women. Many have therefore dismissed sisterhood as a legitimate claim to solidarity, failing to examine the ways that sisterhood continues to be utilized by feminist activists. This article examines qualitative data from a study of a white, middle-class, feminist, antiracist organization that uses the language of sisterhood in its work on behalf of incarcerated women, who are predominantly of color and poor. The author finds not only that sisterhood is simultaneously rooted in women’s experiences with oppression and pride and pleasure but that such language serves complex functions in feminist organizations that seek to work across difference. Beyond its use in creating and sustaining solidarity, sisterhood is utilized to bridge differences in race, class, and life experiences between women and to generate feelings of legitimacy amongst white, middle-class activists.
Fate map of mouse ventral limb ectoderm and the apical ectodermal ridge

The apical ectodermal ridge (AER) is a critical signaling center at the tip of the limb that promotes outgrowth. In mouse, formation of the AER involves a gradual restriction of AER gene expression from a broad ventral preAER domain to the tip of the limb, as well as progressive thickening of cells to form a multilayered epithelium. The AER is visible from embryonic day 10.5 to 13.5 (E10.5–E13.5) in the mouse forelimb. Previous short-term fate mapping studies indicated that, once a cell is incorporated into the AER, its descendents remain within the AER. In addition, some preAER cells appear to become incorporated into the ventral ectoderm. In the present study, we used an inducible CreER/loxP fate mapping approach in mouse to examine the long-term contribution of preAER cells to limb ventral ectoderm, as well as the ultimate fate of the mature AER cells. We used a CreER transgene that contains Msx2 regulatory sequences specific to the developing AER, and demonstrate by marking preAER cells that, at stage 2 of mouse limb bud development, the majority of the ventral ectoderm that protrudes from the body wall later covers only the paw. Furthermore, when Msx2-CreER-expressing preAER cells are marked after the onset of preAER gene expression, a similar domain of paw ventral ectoderm is marked at E16.5, in addition to the AER. Strikingly, mapping the long-term fate of cells that form the mature AER showed that, although this structure is indeed a distinct compartment, AER-derived cells are gradually lost after E12.5 and no cells remain by birth. A distinct dorsal/ventral boarder nevertheless is maintained in the ectoderm of the paw, with the distal-most border being located at the edge of the nail bed. These studies have uncovered new aspects of the cellular mechanisms involved in AER formation and in partitioning the ventral ectoderm in mouse limb.
Quinolinic acid in culture media used for in vitro neurotoxicology studies.

Abstract Serum from several species is frequently added to the incubation media of cells in vitro. The excitotoxin and N- methyl- d -aspartate receptor agonist quinolinic acid was found to be present in serum in concentrations ranging from 59 to 4895 nM. Some neuronal systems are reported to be particularly sensitive to the neurotoxic effects of quinolinic acid. Therefore, quinolinic acid in serum should be considered as a potentially confounding variable in neurotoxicology studies in vitro.
Adsorption of surfactants on minerals for wettability control in improved oil recovery processes

Abstract Chemical-flooding schemes for recovering residual oil have been in general less than satisfactory due to loss of chemicals by adsorption on reservoir rocks, precipitation, and resultant changes in rock wettability. Adsorption and wettability changes are determined mainly by the chemical structure and mix of the surfactants, surface properties of the rock, composition of the oil and reservoir fluids, nature of the polymers added and solution conditions such as salinity, pH and temperature. The mineralogical composition of reservoir rocks plays an important role in determining interactions between reservoir minerals and externally added reagents (surfactants/polymers) and their effects on solid–liquid interfacial properties such as surface charge and wettability. Some of the reservoir minerals can be sparingly soluble causing precipitation and changes in wettabilty as well as drastic depletion of surfactants/polymers. Most importantly, the effect of surfactants on wettability depends not only how much is adsorbed but also on how they adsorb. A water wetted rock surface that is beneficial for displacement of oil can be obtained by manipulating the orientation of the adsorbed layers. New surfactants capable of tolerating harsh conditions created by extremes of pH, temperature or inorganics and capable of interacting favorably with inorganics and polymers are promising for enhanced oil recovery. In this regard, such surfactants as sugar based ones and pyrrolidones are attracting attention, as they are also biodegradable. In many cases, mixed surfactants perform much better than single surfactants due to synergetic effects and ability to alleviate precipitation. Also, addition of inorganics such as silicates, phosphates and carbonates and polymers such as lignins can be used to control the adsorption and the wettability. In this paper, use of specialty surfactants and their mixtures is discussed along with the mechanisms involved.
Parametric instabilities of circularly polarized Alfven waves in high-beta plasmas

CGL relations including the effect of finite ion Larmor radius are used to consider a class of parametric instabilities of finite-amplitude, circularly polarized Alfven waves in high-beta plasmas. The disperison relation governing the instabilities is a sixth-order polynomial which is solved numerically. There are two types of instabilities: a modulational instability at k is less than k(0) and a relatively weak and narrow bandwidth instability at k is less than approximately k(0), where k and k(0) are the wavenumbers of the unstable density fluctuation and the 'pump' wave, respectively. It is shown that these instabilities can occur for left-handed pump waves and that the modulational instability is unstable over a very broad band in k with a maximum growth rate at finite k is not equal to 0.
Effect of erythrocyte deformability on in vivo red cell transit time and hematocrit and their correlation with in vitro filterability.

Abstract Indicator dilution techniques were applied to measure mean transit time of fluorescently labeled red blood cells (RBCs) (TTRBC) and plasma (TTpl) between functionally paired arterioles and venules (A-V) in cremaster muscle (rat) for normal RBCs and cells hardened by in vitro incubation in graded concentrations of glutaraldehyde. Dispersion of a bolus introduced into the contralateral femoral artery permitted computation of TT by cross-correlation of fluorescence intensity-time curves in A-V pairs. Parallel in vitro assessments of RBC deformability were made by filtration through 5-μm pore Nuclepore filters to express deformability in terms of the ratio of resistance to flow through a pore with RBCs present to that with suspending medium alone, β. The average microvascular hematocrit (Hmicro) normalized with respect to systemic hematocrit (Hsys) was calculated from TTRBC and TTpl. For 26 A-V pairs of the third and fourth orders of branching, TTRBC averaged 0.63 sec for normal control cells (β = 2.61), and TTpl averaged 0.85 sec with an average TTRBC/TTpl equal to 0.85. The corresponding value of Hmicro /Hsys was significantly
Are regional effects on local diversity more important in marine than in terrestrial communities

In a thought provoking article, Cornell and Harrison (2012) explore the reasons for different perspectives on the importance of the regional species pool in governing local species diversity on land vs the sea. I begin my commentary by underscoring the importance of regional processes in shaping local diversity then react to their explanations for the different system-based perspectives and conclude by proposing an experimental design to test for differences in regional enrichment of local species richness between marine and terrestrial systems. That the number of species in a particular local
The long-lived fusogenic state induced in erythrocyte ghosts by electric pulses is not laterally mobile

The long-lived fusogenic state induced in spherical-shaped erythrocyte ghosts by electric field pulses (Sowers, A.E. 1984. J. Cell Biol. 99:1989–1996; Sowers, A.E. 1986. J. Cell Biol. 102:1358–1362) was studied in terms of how the fusion yield depended on both (a) the location where membrane-membrane contact took place with respect to the orientation of the electric pulse and (b) the time interval between the pulse treatment and membrane-membrane contact. Fusion yields were greater for membrane-membrane contact locations closer to where the pulse-induced transmembrane voltage was expected to be greatest and showed a time interval-dependent accelerating decay. The portion of the membrane that became fusogenic included the area up to a latitude of approximately 38 degrees of arc towards the equators of the membranes. A time interval-dependent increase or decrease in rate of decay in the fusion yield for membrane-membrane contacts induced closer to the equator of the membranes did not occur showing that the pulse-induced fusogenic state is immobile in the early 5–45-s interval after induction and has a rate of decay, which does not permit long time interval changes in lateral position to be measured.
Matrix metalloproteinases: their potential role in the pathogenesis of diabetic nephropathy

Matrix metalloproteinases (MMPs), a family of proteinases including collagenases, gelatinases, stromelysins, matrilysins, and membrane-type MMPs, affect the breakdown and turnover of extracellular matrix (ECM). Moreover, they are major physiologic determinants of ECM degradation and turnover in the glomerulus. Renal hypertrophy and abnormal ECM deposition are hallmarks of diabetic nephropathy (DN), suggesting that altered MMP expression or activation contributes to renal injury in DN. Herein, we review and summarize recent information supporting a role for MMPs in the pathogenesis of DN. Specifically, studies describing dysregulated activity of MMPs and/or their tissue inhibitors in various experimental models of diabetes, including animal models of type 1 or type 2 diabetes, clinical investigations of human type 1 or type 2 diabetes, and kidney cell culture studies are reviewed.
The role of alpha-helical structure in p53 peptides as a determinant for their mechanism of cell death: necrosis versus apoptosis

Peptides derived from the N-terminal and C-terminal regions of the p53 tumor suppressor protein, linked to the membrane transduction domain of Antennapedia, have both been found to have significant cytotoxic effects selectively in human cancer cells. However, the N-terminal and C-terminal p53 peptides apparently display very different mechanisms for their anticancer effects. These differential effects can be attributed to dissimilar abilities to form distinctive 3-dimensional structures in extracellular-matrix-like aqueous solution that enable unique and selective cancer cell membrane penetration and effect. N-terminally based p53 peptides, with their ability to form distinctive S-shaped helix-loop-helix structures, are able to rapidly disrupt cancer cell membranes via toroidal-like pore formation causing necrosis; conversely, C-terminally based p53 peptides, due to their more random coil configuration, can be transduced across cancer cell membranes and bind to its intracellular target to cause a Fas pathway mechanism of apoptosis.
Superconducting fibers from organometallic precursors: Part III. Pyrolytic processing of precursor fibers

Sixty−70 μm diameter preceramic fibers, extruded from THF solutions containing 1:2:3 stoichiometric mixtures of yttrium, barium, and copper carboxylates, were pyrolytically transformed into ceramic fibers using controlled heating schedules and reactive atmospheres. The objectives of the work reported here were to identify appropriate processing conditions such that during pyrolysis the preceramic fibers would (1) eliminate the organic ligands without pore or void formation, (2) reach full density with a controlled grain size, and (3) form orthorhombic phase, 123 fibers with reasonable mechanical properties. The mechanisms of organic ligand decomposition and loss were examined using mass spectral fragmentation and TGA. Microstructural and phase evolution were correlated with heating schedules and atmospheres, using XRD, DTA, SEM, and limited flux exclusion studies. The mechanisms of decomposition of the spinnable mixtures suggest intermolecular rather than intramolecular decomposition pathways. Different pyrolysis atmospheres were also examined to explore methods of controlling the degradation process. Slow pyrolysis in air followed by oxygen anneals appears to give superior fibers in terms of controlled grain size and phase. The pyrolyzed fibers exhibit the appropriate orthorhombic phase according to x-ray powder diffractometry. Preliminary flux exclusion measurements demonstrate that the fibers are superconducting although the measured δTc is not exceptional.
Open source REST services for environmental sensor networking

Abstract The greatest challenge in the implementation of environmental sensing networks is converting a large variety of data streams from diverse sensors, often in proprietary protocols, to international standards such as Extensible Markup Language (XML) with Open Geospatial Consortium (OGC) XML tagging and web service standards. Implementing standards throughout the architecture will not only enable interoperability and reduce cost but will allow scientists to contribute to sensor network innovation. This article introduces open source Representational State Transfer (REST) services created specifically for environmental monitoring. OGC standards are suggested to help guide future community development for sensor description and registration. This article contributes to the design and implementation of affordable, self-documenting, near-real-time geospatial sensor webs for environmental monitoring using international standards.
The effect of 5-bromodeoxyuridine on the postnatal development of the rat cerebellum: morphologic and radioautographic studies.

Effects of a thymidine analog, 5-bromodeoxyridine (BrdU), on the development of rat cerebella were studied. BrdU, when 15 milligram per 100 gram body weight was injected twice daily into 2-day-old rats for three consecutive days, caused a transient inhibition of cell formation and destruction of stem cells in the external granular layer. This was followed by a prolonged period of regeneration with delayed dissolution of the external granular layer; however, the restitution in cell number was incomplete and resulted in a miniature cerebellum with significantly reduced myelination at 35 days of age. The regeneration of the external granular layer appeared to alter the synchronized morphogenetic processes of the cerebellar cortex. The “desynchronization” of morphogenetic events appears to account for the peculiar cytoarchitectonic organization of the cerebellar cortex in the BrdU-injected animals, i.e., irregular stacking of Purkinje cells, formation of granule cell ectopia, and sagittal alignment of parallel fibers in the molecular layer. It is postulated that the misalignment of parallel fibers is the consequence of BrdU substitution in place of thymine in the nuclear DNA of granule cell precursors. The present schedule of BrdU injections also appeared to reveal an additional, early period of oligodendroglial proliferative activity which did not coincide with the onset of myelination.
Inference from clustering with application to gene-expression microarrays.

There are many algorithms to cluster sample data points based on nearness or a similarity measure. Often the implication is that points in different clusters come from different underlying classes, whereas those in the same cluster come from the same class. Stochastically, the underlying classes represent different random processes. The inference is that clusters represent a partition of the sample points according to which process they belong. This paper discusses a model-based clustering toolbox that evaluates cluster accuracy. Each random process is modeled as its mean plus independent noise, sample points are generated, the points are clustered, and the clustering error is the number of points clustered incorrectly according to the generating random processes. Various clustering algorithms are evaluated based on process variance and the key issue of the rate at which algorithmic performance improves with increasing numbers of experimental replications. The model means can be selected by hand to test t...
Generalizing the Krein–Rutman theorem, measures of noncompactness and the fixed point index

If L : Y → Y is a bounded linear map on a Banach space Y, the “radius of the essential spectrum” or “essential spectral radius” ρ(L) of L is well-defined and there are well-known formulas for ρ(L) in terms of measures of noncompactness. Now let $${C \subset D}$$ be complete cones in a normed linear space (X, || · ||) and f : C → C a continuous map which is homogeneous of degree one and preserves the partial ordering induced by D. We prove (see Section 2) that various obvious analogs of the formulas for the essential spectral radius for the case f : C → C have serious defects, even when f is linear on C. We propose (see (3.5)) a definition for ρ C (f), the “cone essential spectral radius of f,” which avoids these difficulties. If $${{\tilde r}_{C}(f)}$$ denotes the (Bonsall) cone spectral radius of f, we conjecture (see Conjecture 4.1) that if $${\rho_{C}(f) < {\tilde r}_{C}(f)}$$ , then there exists $${u \in C {\backslash} \, \{0\}}$$ with f(u) = ru where r ≔ r C (f). If f satisfies certain additional conditions (for example, if f is a compact perturbation of a map which is linear on C), we obtain the conclusion of the conjecture; but in general we observe (Remark 4.7) that the conjecture is intimately related to old and difficult conjectures in asymptotic fixed point theory. In Section 5 we briefly discuss extensions of generalized max-plus operators which were our original motivation and for which Conjecture 4.1 is already nontrivial.
Observations of the Response of Thermocline Currents to a Hurricane

Abstract In September 1985, the eye of Hurricane Gloria passed within about 100 km of a current meter mooring in the western North Atlantic. Data from this mooring provide a clear view of the vertical structure of the near-inertial wake in the main thermocline. The response at 159 m was strong (>25 cm s−1 amplitude) and lasted about 18 days. At greater depths, the response was weaker and more irregular. The phase of the near-inertial currents increased with depth, consistent with the downward spreading of enemy. The total phase change across the thermocline reached about a half cycle seven days after the hurricane's passage, indicating a large vertical scale of the response. The observations are briefly compared with other time series measurements (on the continental margin) and with models.
Risk Pooling Advantages of Manufacturing Network Configuration

The decision of a firm to set up a plant network is influenced by a number of factors, including demand fluctuations across its portfolio of products, logistics costs, and service level requirements. Product plant networks offer the benefits of consolidated production and reduced transshipment costs; on the other hand, process plant networks allow intensive dedication to process expertise and economies of scale. In this paper, we show that, aside from these benefits, process plant networks offer significant risk pooling advantages under a wide range of conditions. We analytically demonstrate that, even without accounting for economies of scale advantages, firms may prefer the process plant network configuration due to the risk pooling benefits offered.
Can Long{run Risks Explain Commodity Excess Risk Premium Puzzle?

This paper extends existing asset pricing models by dierentiating between the storable and nonstorable components of aggregate consumption and by introducing a commodity storage technology to the economy. I use this extended model to elaborate the interactions between long-run consumption risks (a la Bansal and Yaron (2004)) and commodity price/return dynamics. By demonstrating a relationship between expected aggregate consumption growth rates and commodity spot prices, I propose a new explanation for the observed excess volatility and excess returns of commodity futures. My model suggests that the instantaneous supply and spot prices of an exhaustible/storable commodity are sensitive to long-run trends even in the absence of changes in short-term demand. My structural model elaborates "storability" as a major factor inuencing the consumption and wealth betas of commodities. Empirically, I show that returns to commodity indexes predict consumption growth in the future.
Pioneer brand advantage and consumer behavior: A conceptual framework and propositional inventory

What are the behavioral origins of pioneer brand advantage? This article provides an integrative conceptual framework and propositional inventory to help more fully understand this multifaceted phenomenon. It is proposed that there are three sources of entry-order information that work through various psychological processes and affect multiple decision process variables. The conceptual framework translates into eight testable propositions. New exploratory evidence is presented. Managerial implications are discussed.