cssi/SciSciGPT-SciSciNet huggingface dataset:
Water resources in the history of the Palestine-Israel conflict

The quest for water resources by Zionist leaders started in the early years of the Zionist movement. Attempts were made to delimit Palestine according to rivers and headwaters. This quest has been independent of the political status of the territory of Palestine. The quest was intense in the early 1950s during the Johnston negotiations, and it became especially crucial after the 1967 occupation by Israel of the rest of Palestine, the West Bank. Lebanon's Litani river has been included in Israeli considerations, as well as the Jordan river's tributary the Yarmuk river. The Kingdom of Jordan's development plans for the latter may be compromised. Control of underground water resources in the West Bank is deemed essential to Israel, given their importance to the ground supply of pre-1967 Israel. Israel is unlikely to relinquish control of the water resources of the West Bank in the event of a political settlement.
ERECTILE DYSFUNCTION AFTER RADICAL PROSTATECTOMY: HEMODYNAMIC PROFILES AND THEIR CORRELATION WITH THE RECOVERY OF ERECTILE FUNCTION

Purpose: Despite the advent of nerve sparing radical prostatectomy some men experience erectile dysfunction. Many of these men have vasculogenic erectile impairment in the form of arterial insufficiency or venous leakage. Recent data imply that early postoperative injection therapy may decrease the rate of erectile dysfunction. We defined hemodynamic patterns in patients who underwent bilateral nerve sparing radical prostatectomy to assess the chronology of venous leakage development and explore the correlation of hemodynamic profiles with the return of functional erection 12 months postoperatively.Materials and Methods: Patients with excellent preoperative erectile function who underwent bilateral nerve sparing surgery and had no pharmacological support for erectile dysfunction in the initial 12 months after surgery received vascular evaluation at presentation. Vascular evaluation involved cavernosometry or penile ultrasonography. Patients were then interviewed again at least 12 months postoperatively to...
OXYGEN CONCENTRATIONS ACTUALLY ADMINISTERED TO PATIENTS DURING CYCLOPROPANE ANAESTHESIA.

SUMMARY Oxygen concentrations were measured in the gas mixtures of cyclopropane and oxygen delivered to patients during a short operation (35 minutes). It has been demonstrated that the amount of oxygen actually administered is considerably lower than it appears on the flowmeters of the anesthesia apparatus. ZUSAMMENFASSUNG Die Sauerstoffkonzentrationen in Gasgemischen von Cyclopropan und Sauerstoff, welche man Patienten wahrend kurzer Eingriffe von etwa 35 min Dauer verabreichte, wurden gemessen; Es konnte gezeigt werden, dass die tatsachliche Sauerstoffkonzentration betrachtlich unterhalb jener Werte liegt, die von den Flowmetern des Narkoseapparates angezeigt wurden.
Localization of the structural genes for hexokinase-1 and inorganic pyrophosphatase on region (pter→q24) of human chromosome 10

Concordant expression of human hexokinase-1 and inorganic pyrophosphatase was established in somatic cell hybrids between thymidine kinase-deficient Chinese hamster cells and human fibroblasts carrying a translocation of the distal third of the long arm of chromosome 10 to chromosome 17. Neither human hexokinase-1 nor human inorganic pyrophosphatase expression segregated concordantly with human cytoplasmic glutamic-oxaloacetic transaminase expression.
Organelle-Based Aggregation and Retention of Damaged Proteins in Asymmetrically Dividing Cells

Aggregation of damaged or misfolded proteins is a protective mechanism against proteotoxic stress, abnormalities of which underlie many aging-related diseases. Here, we show that in asymmetrically dividing yeast cells, aggregation of cytosolic misfolded proteins does not occur spontaneously but requires new polypeptide synthesis and is restricted to the surface of ER, which harbors the majority of active translation sites. Protein aggregates formed on ER are frequently also associated with or are later captured by mitochondria, greatly constraining aggregate mobility. During mitosis, aggregates are tethered to well-anchored maternal mitochondria, whereas mitochondria acquired by the bud are largely free of aggregates. Disruption of aggregate-mitochondria association resulted in increased mobility and leakage of mother-accumulated aggregates into the bud. Cells with advanced replicative age exhibit gradual decline of aggregates-mitochondria association, likely contributing to their diminished ability to rejuvenate through asymmetric cell division.
The roles of shear and cross-correlations on the fluctuation levels in simple stochastic models

Highly simplified models of random flows interacting with background microturbulence are analyzed. In the limit of very rapid velocity fluctuations, it is shown rigorously that the fluctuation level of a passively advected scalar is not controlled by the rms shear. In a model with random velocities dependent only on time, the level of cross-correlations between the flows and the background turbulence regulates the saturation level. This effect is illustrated by considering a simple stochastic-oscillator model, both exactly and with analysis and numerical solutions of the direct-interaction approximation. Implications for the understanding of self-consistent turbulence are discussed briefly.
Identification and Characterization of Inhibitors of Human Apurinic/apyrimidinic Endonuclease APE1

APE1 is the major nuclease for excising abasic (AP) sites and particular 3′-obstructive termini from DNA, and is an integral participant in the base excision repair (BER) pathway. BER capacity plays a prominent role in dictating responsiveness to agents that generate oxidative or alkylation DNA damage, as well as certain chain-terminating nucleoside analogs and 5-fluorouracil. We describe within the development of a robust, 1536-well automated screening assay that employs a deoxyoligonucleotide substrate operating in the red-shifted fluorescence spectral region to identify APE1 endonuclease inhibitors. This AP site incision assay was used in a titration-based high-throughput screen of the Library of Pharmacologically Active Compounds (LOPAC1280), a collection of well-characterized, drug-like molecules representing all major target classes. Prioritized hits were authenticated and characterized via two high-throughput screening assays – a Thiazole Orange fluorophore-DNA displacement test and an E. coli endonuclease IV counterscreen – and a conventional, gel-based radiotracer incision assay. The top, validated compounds, i.e. 6-hydroxy-DL-DOPA, Reactive Blue 2 and myricetin, were shown to inhibit AP site cleavage activity of whole cell protein extracts from HEK 293T and HeLa cell lines, and to enhance the cytotoxic and genotoxic potency of the alkylating agent methylmethane sulfonate. The studies herein report on the identification of novel, small molecule APE1-targeted bioactive inhibitor probes, which represent initial chemotypes towards the development of potential pharmaceuticals.
Analysis in Vivo of Turnip Crinkle Virus Satellite RNA C Variants with Mutations in the 3*-Terminal Minus-Strand Promoter

Turnip crinkle virus and its associated RNA, sat-RNA C, share similar, but not identical hairpins near their 3* ends and terminate with CCUGCCC-OH, which forms a single-stranded tail. With an in vitro transcription system containing partially purified TCV RdRp, the 3*-terminal 29 bases making up the hairpin and single-stranded tail were previously demonstrated to be required for transcription, and alterations in the stem, but not the loop, could affect template activity (C. Song and A. E. Simon, 1995, J. Mol. Biol. 254, 6 – 14). We have now analyzed sat-RNA C mutants in the 3* hairpin for ability to accumulate in vivo. While active templates in vitro were able to accumulate in vivo, some very weak templates in vitro were also able to accumulate in vivo without reversion or second-site alterations. Computer models of hairpin structure indicated that biologically active promoters could have hairpins less stable than wild type, with loops of variable length and sequence, and without a need for a 6-base single-stranded tail. In addition, transcripts containing compensatory exchanges in the upper stem region that had limited activity in vitro were biologically active in vivo, indicating that positioning of specific bases in the stem is not required to produce an active minus-strand promoter. q 1997 Academic Press
Leading the Way An Analysis of the Effect of Religion on the Latino Vote

To examine the impact of religion on the Latino vote, we draw on data from a pre-election survey of 1,603 Latino registered voters conducted in October 2004. We advance the argument that religious identity is politically salient only among Latino evangelicals. Controlling for a host of voting determinants, we show that religious identity has an independent effect on the vote among Latino evangelicals. Furthermore, Latino evangelicals who identify with the Republican Party are found to be more-committed supporters of the incumbent president. The existence of a religion gap suggests that the Latino electorate may become much less cohesive as a voting bloc as religious affiliation becomes more pluralistic in the Latino community.
Earthquake analysis of arch dams including dam-water-foundation rock interaction

The available substructure method and computer program for the earthquake response analysis of arch dams, including the effects of dam-water interaction, reservoir boundary absorption, and foundation rock flexibility, is extended to include the effects of dam-foundation rock interaction with inertia and damping of the foundation rock considered. Efficient techniques are developed for evaluating the foundation impedance terms, computationally the most demanding part of the procedure.
Improved statistical models for limited datasets in uncertainty quantification using stochastic collocation

This paper presents a data-driven framework for performing uncertainty quantification (UQ) by choosing a stochastic model that accurately describes the sources of uncertainty in a system. This model is propagated through an appropriate response surface function that approximates the behavior of this system using stochastic collocation. Given a sample of data describing the uncertainty in the inputs, our goal is to estimate a probability density function (PDF) using the kernel moment matching (KMM) method so that this PDF can be used to accurately reproduce statistics like mean and variance of the response surface function. Instead of constraining the PDF to be optimal for a particular response function, we show that we can use the properties of stochastic collocation to make the estimated PDF optimal for a wide variety of response functions. We contrast this method with other traditional procedures that rely on the Maximum Likelihood approach, like kernel density estimation (KDE) and its adaptive modification (AKDE). We argue that this modified KMM method tries to preserve what is known from the given data and is the better approach when the available data is limited in quantity. We test the performance of these methods for both univariate and multivariate density estimation by sampling random datasets from known PDFs and then measuring the accuracy of the estimated PDFs, using the known PDF as a reference. Comparing the output mean and variance estimated with the empirical moments using the raw data sample as well as the actual moments using the known PDF, we show that the KMM method performs better than KDE and AKDE in predicting these moments with greater accuracy. This improvement in accuracy is also demonstrated for the case of UQ in electrostatic and electrothermomechanical microactuators. We show how our framework results in the accurate computation of statistics in micromechanical systems.
Delayed silicone breast implant infection with Mycobacterium avium-intracellulare

Mycobacterial breast implant infection is a rare complication after augmentation mammaplasty. A review of the literature demonstrates multiple examples of breast implant infection with Mycobacterium fortuitum, but only rare discussion of Mycobacterium avium-intracellulare (MAC). The authors report an unusual case of MAC breast implant infection in a patient with a complex surgical history.
Spectroscopic studies of the dodecanuclear chromium complex Cr12O9(OH)3(pivalate)15: confirmation of the presence of twelve Cr(III) centers and the crystal structure of Cr12O9(OH)3(pivalate)15·2PrOH·9H2O

Abstract The complex originally reported to be ‘Cr12O12(pivalate)15’ has been examined by a number of spectroscopic techniques in order to elucidate the chromium valence states. By charge balance arguments, the complex could, for example, contain nine Cr(III) and three Cr(IV) centers, contain 11 Cr(III) and one Cr(VI) center or could possess three protons, not detected by X-ray crystallography, and 12 Cr(III) centers. While a recent neutron diffraction study has suggested the existence of three additional and disordered deuterons (and thus 12 Cr(III) centers), the complex has been studied by several complementary spectroscopic techniques which confirm the formula to be Cr12O9(OH)3(pivalate)15.
Femoral/humeral strength in early African Homo erectus.

Lower-to-upper limb-bone proportions give valuable clues to locomotor behavior in fossil taxa. However, to date only external linear dimensions have been included in such analyses of early hominins. In this study, cross-sectional measures of femoral and humeral diaphyseal strength are determined for the two most complete early Homo erectus (or ergaster) associated skeletons—the juvenile KNM-WT 15000 and the adult KNM-ER 1808. Modern comparative samples include an adult human skeletal sample representative of diverse body shapes, a human longitudinal growth series, and an adult chimpanzee sample. When compared to appropriately age-matched samples, both H. erectus specimens fall very close to modern human mean proportions and far from chimpanzee proportions (which do not overlap with those of humans). This implies very similar mechanical load-sharing between the lower and upper limbs, and by implication, similar locomotor behavior in early H. erectus and modern humans. Thus, by the earliest Pleistocene (1.7 Ma), completely modern patterns of bipedal behavior were fully established in at least one early hominin taxon.
Interferometers vs Monochromators: Separating the Optical and Digital Advantages

Fourier transform (FT) and grating infrared spectrophotometers are compared from a theoretical viewpoint in terms of the multiplex advantage of FT spectrometers, the relative optical throughputs, the comparative performance of the detectors used with each type of system, and other more minor parameters. The signal/noise ratios of spectra measured using commercial FT and grating spectrophotometers are compared. The relative performance varies with wavenumber in the manner forecast theoretically, although the experimental performance of the FT spectrometer is slightly worse than we predicted. Optimum applications for each type of instrument are discussed in terms of these results.
Embedded differential space-time coding for wireless broadcast

An embedded differential space-time coding method is proposed for wireless broadcast application in this work. Our previous work investigated embedded space-time codes for layered media broadcast. In such a system, a transmitter sends out multi-layer source signals by encoding different layers with different space-time codes. Then, the receiver can retrieve a different amount of information depending on the number of antennas it has as well as the level of receiving power. The receiving terminals with one antenna can decode only the base layer information with a low complexity while terminals with more antennas can retrieve more layers of information. In this research, we further consider the case when the channel state information (CSI) is unknwon. The differential coding technique is adopted here. Transmitted symbols are encoded as a certain combination of previous symbols so that the receiver can retrieve the information without CSI. We explore the embedded design with differential STC to enable layered media transmission. Differential detection with Kalman filtering is also investigated to help improve performance.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Introduction: The Continuing Legacy of Melvin Ember (1933-2009)

This article introduces the special issue and provides a brief overview of Melvin Ember’s life and work.
New Majors and the Feminization of Psychology: Testing and Extending the Rajecki-Metzner Model

Records of 445 new psychology majors—and responses from 301 returned questionnaires—were used to (a) test and extend a generic model for academic pathways to the undergraduate major and (b) investigate feminization of the field. The model holds that a student's contact with basic college psychology courses is a crucial element leading to a decision to major in the field. Our data supported this formulation. Concerning feminization, 74% of the applicants were women. As groups, however, women and men were not reliably different on features such as school backgrounds, psychology course histories, self-reported influences on and certain reasons for the decision to major, or plans following graduation. Feminization was thus evident in numbers, not academic characteristics.
Crack growth across colony boundaries in binary lamellar TiAl

The crack growth across a boundary between two colonies, i.e. regions of differing lamellar orientation, in two-phase lamellar Ti-Al is studied computationally to quantify the influence of such boundaries on toughening, as observed in recent in-situ fracture studies. The model represents the lamellar Ti-Al as gamma-phase lamellae, modeled as bulk elastic-viscoplastic material, interspersed with alpha(2)-phase lamellae for which either the alpha(2) phase or alpha(2)-gamma interface are considered as weak planes for fracture. Computationally, dynamic plane-strain analyses of the crack propagation are carried out. Fracture in both phases is accommodated using a cohesive surface formulation that permits crack growth and nucleation to evolve naturally. Results show that the lamellar misorientation across a boundary, the thickness of the boundary region, and the spatial offset between successive weak lamellae, all play a role in inhibiting crack propagation across the boundary. The gamma phase plasticity has a comparatively small influence on the toughening. The enhancements in applied stress intensities required to nucleate cracks across the colony boundary are comparable to those observed experimentally when the weak-plane spacing is comparable to the spacing of microcracks and crack plane offsets observed experimentally. (C) 2002 Elsevier Science B.V. All rights reserved.
Pump-probe Microscopy Captures Cellular Detail of Melanoma In-vivo.

Pump-probe imaging of melanin with near-infrared pulses coupled with multphoton autofluorescence captures both chemical contrast and cellular detail in a live, developing melanoma.
Enhancement of the dynamical dipole moment in adsorbed molecules: Theoretical studies for CO/Cu(100)

Ab initio cluster-model calculations have been performed for the C-O stretch of CO/Cu(100). Attention has been given to the dynamical dipole moment which is decomposed into contributions from the $\ensuremath{\sigma}$ and $\ensuremath{\pi}$ electrons of the cluster. The largest contribution is from the $\ensuremath{\pi}$ electrons, and the increase in the value of this contribution for CO/Cu(100) over that for free CO is due, mainly, to the metal to CO $2{\ensuremath{\pi}}^{*}$ donation. Our theoretical value for the enhancement of the dynamical dipole moment for adsorbed CO is consistent with results of recent experiments. For the first time, we present direct ab initio evidence for the important role which the metal-to-CO $2{\ensuremath{\pi}}^{*}$ donation plays for this enhancement.
Dose Effects of Growth Hormone during Puberty

During puberty, the production rate of growth hormone (GH) doubles and is associated with an increase in growth velocity. A significant percentage of the final adult height is attained during puberty, then after puberty, the production rate of GH decreases with age. In children with GH deficiency, it is known that the dosage of GH, in addition to the duration of treatment, can greatly influence the final adult height. At present, the dosage of GH given to children of short stature is kept at a constant rate throughout puberty. Thus, a study was conducted to investigate the effects of a higher dose of GH given to GH-deficient children during puberty. In this article, the design and results of the investigation and the importance of the findings will be discussed.
Bacteriophage SPP1 Chu Is an Alkaline Exonuclease in the SynExo Family of Viral Two-Component Recombinases

Many DNA viruses concatemerize their genomes as a prerequisite to packaging into capsids. Concatemerization arises from either replication or homologous recombination. Replication is already the target of many antiviral drugs, and viral recombinases are an attractive target for drug design, particularly for combination therapy with replication inhibitors, due to their important supporting role in viral growth. To dissect the molecular mechanisms of viral recombination, we and others previously identified a family of viral nucleases that comprise one component of a conserved, two-component viral recombination system. The nuclease component is related to the exonuclease of phage lambda and is common to viruses with linear double-stranded DNA genomes. To test the idea that these viruses have a common strategy for recombination and genome concatemerization, we isolated the previously uncharacterized 34.1 gene from Bacillus subtilis phage SPP1, expressed it in Escherichia coli, purified the protein, and determined its enzymatic properties. Like lambda exonuclease, Chu (the product of 34.1) forms an oligomer, is a processive alkaline exonuclease that digests linear double-stranded DNA in a Mg(2+)-dependent reaction, and shows a preference for 5'-phosphorylated DNA ends. A model for viral recombination, based on the phage lambda Red recombination system, is proposed.
Treating chronic pediatric conditions: pirenzepine ophthalmic gel (PIR) for the slowing of progression of pediatric myopia as a model pediatric development program

Purpose There is a growing interest in developing drugs for the treatment of pediatric diseases. Combining pediatric development with chronic use and prevention of disease progression indication(s) present special challenges to the clinical pharmacologist. Myopia is a very prevalent disease (up to 80% in some countries), for which current treatments meet only the optical pathology, not ocular comorbidity, or the underlying structural abnormality. Pirenzepine is a m1-selective muscarinic antagonist, long used orally in Europe, and effective in animal models of myopia. Methods Valley Forge developed a stable ophthalmic gel. The ocular safety and tolerance of PIR was investigated in a short-term study with two year follow-up in myopic children. Subsequently, multi-year, worldwide studies were conducted on the safety and efficacy of the highest tolerated concentration. Results In an initial Phase 2 study, myopic children tolerated up to 2% PIR. In two subsequent one year Phase 2 studies, 2% PIR, b.i.d. reduced the rate of progression of myopia by ~50%. While there were some traditional m3-antagonist undesirable effects observed (e.g., mydriasis, accommodation complaints), they were for the most part not therapy limiting, and were much less than expected from a non-selective muscarinic antagonist such as atropine. Conclusions PIR presents promise as a chronic treatment for prevention of disease progression for pediatric myopia. A continuing development program is planned. Clinical Pharmacology & Therapeutics (2004) 75, P23–P23; doi: 10.1016/j.clpt.2003.11.086
THE INFLUENCE OF DIET ON THE CHOLESTEROL CONCENTRATION OF THE BLOOD SERUM IN NORMAL, SPAYED, AND HYPOTHYROID MONKEYS1

THE INFLUENCE of dietary cholesterol on the concentration of cholesterol in the blood has been the subject of much study both in man and in experimental animals. Most investigators have failed to find any consistent effect of a single cholesterol-rich meal. Thus, Sperry (1936) reported that in ten experiments the average change in serum cholesterol concentration was zero during the three to four hours following the ingestion by healthy human subjects of a breakfast of three eggs, six slices of bacon, two slices of toast heavily buttered, two cups of coffee with cream, and orange juice. Frohling (1936) reported that only in one instance did the administration of as much as 15 gm. cholesterol in olive oil have any effect on serum cholesterol concentration. Even in rabbits, in which large accumulations of cholesterol result from continued feeding, a single dose of cholesterol has been reported not to affect the concentration in the blood (Ssokoloff and Mjassnikow, 1923; Iljinsky, 1926-27).
Maximizing pin alignment in semi-custom chip circuit layout

Abstract We consider the problem of logically permuting pins of a semi-custom chip circuit layout in order to maximize the number of connections that can be realized in the polysilicon layer. As the problem is NP-hard, we present an infinite hierarchy of heuristics, including an algorithm which produces an optimal solution. The heuristics can be tuned to yield approximate solutions of varying degree, as well as an optimal solution. The tradeoff lies in the length of runtime. We have implemented the procedures and demonstrate their behavior with one real and various randomly generated examples.
Male Economic Gain from Female Subordination: A Caveat and Reanalysis

This comment speaks directly to the conceptual and methodological shortcomings of a single article (Szymanski, b), but has a broader purpose. Research reports concerning and/or employing income distributional measures have been appearing in the sociological literature with increasing frequency over the past few years. Many of these reports deal with the size distribution of subgroup income not for descriptive purposes, but to make important theoretical points. It is unfortunate that for far too long income distribution has been studied primarily by economists (when it has been studied at all, other than descriptively). This means that sociologists approaching the field without care run the considerable risk of unknowingly accepting the simplifying assumptions of many economists, some of whom are known as much for their concern with statistical rigor as for their seeming dismissal of questions of measurement validity.' Measurement invalidity is the bane of distributional research, and is probably the greatest problem currently facing students of the area.2 The greatest difficulty is that too many aren't even aware that it is a problem. Szymanski is but one case in point. I shall first review the problems of his analysis and interpretation, and then reanalyze his data to arrive at quite different conclusions. Szymanski investigates the economic impact on males of earnings discrimination against females. He concludes: ". . . while men as a whole do not earn more because of sexual discrimination . . . the poorer paid whites do benefit somewhat at the expense of women, while the better paid males lose." This conclusion follows, he claims, from two findings: (1) that male median income is unaffected by discrimination against females; and (2) that male inequality (as measured by the Gini Concentration Ratio) decreases as discrimination against females increases. Given these two, he says, males at the top must lose and those at the bottom must gain. His conclusions, of course, would not follow from his findings even if his findings were correct, which they are not. The assumption that they do follow is based on a misunderstanding of what the Gini is. The Gini is a notoriously poor measure of the well-being of any segment of a Lorenz curve (see Alker and Russet; Bronfenbrenner; Kravis).
A study of organic nitrates formation in an urban plume using a Master Chemical Mechanism

Abstract Secondary organic chemistry inside a typical urban plume in the North-East of the United States has been studied using a highly detailed chemical model, based upon the Master Chemical Mechanism (MCM). The model results have been qualitatively compared to measurements taken during three flights of the NOAA WP-3D aircraft, which sampled a plume from the New York City area during the NEAQS 2004 campaign. The model has been used to study the formation processes and photochemical evolution of alkyl nitrates. While long-chain (C5) alkyl nitrates are produced for 90% or more from the oxidation of a single parent alkane, short-chain ( C 4 ) alkyl nitrates can be formed from several precursors. The relative importance of each production route has been quantitatively determined thanks to the high level of chemical detail provided by the MCM. These secondary routes to the formation of alkyl nitrates include the oxidation of longer-chain alkanes and oxygenated intermediates, like carbonyls, peroxides and carboxylic acids.
Late-postnatal cannabinoid exposure persistently elevates dendritic spine densities in area X and HVC song regions of zebra finch telencephalon.

Abstract Centrally acting cannabinoids are well known for their ability to impair functions associated with both learning and memory but appreciation of the physiological mechanisms underlying these actions, particularly those that persist, remains incomplete. Our earlier studies have shown that song stereotypy is persistently reduced in male zebra finches that have been developmentally exposed to cannabinoids. In the present work, we examined the extent to which changes in neuronal morphology (dendritic spine densities and soma size) within brain regions associated with zebra finch vocal learning are affected by late-postnatal cannabinoid agonist exposure. We found that daily treatment with the cannabinoid agonist WIN55212-2 (WIN, 1 mg/kg IM) is associated with 27% and 31% elevations in dendritic spine densities in the song regions Area X and HVC, respectively. We also found an overall increase in cell diameter within HVC. Changes in dendritic spine densities were only produced following developmental exposure; treatments given to adults that had completed vocal learning were not effective. These findings have important implications for understanding how repeated cannabinoid exposure can produce significant, lasting alteration of brain morphology, which may contribute to altered development and behavior.
The Role of Vascular Endothelial Growth Factor in Neurodegeneration and Cognitive Decline: Exploring Interactions With Biomarkers of Alzheimer Disease

Importance A subset of older adults present post mortem with Alzheimer disease (AD) pathologic features but without any significant clinical manifestation of dementia. Vascular endothelial growth factor (VEGF) has been implicated in staving off AD-related neurodegeneration. Objective To evaluate whether VEGF levels are associated with brain aging outcomes (hippocampal volume and cognition) and to further evaluate whether VEGF modifies relations between AD biomarkers and brain aging outcomes. Design, Setting, and Participants Biomarker analysis using neuroimaging and neuropsychological outcomes from the Alzheimer’s Disease Neuroimaging Initiative. This prospective longitudinal study across North America included individuals with normal cognition (n = 90), mild cognitive impairment (n = 130), and AD (n = 59) and began in October 2004, with follow-up ongoing. Main Outcomes and Measures Cerebrospinal fluid VEGF was cross-sectionally related to brain aging outcomes (hippocampal volume, episodic memory, and executive function) using a general linear model and longitudinally using mixed-effects regression. Alzheimer disease biomarker (cerebrospinal fluid β-amyloid 42 and total tau)–by–VEGF interactions evaluated the effect of VEGF on brain aging outcomes in the presence of enhanced AD biomarkers. Results Vascular endothelial growth factor was associated with baseline hippocampal volume ( t 277 = 2.62; P = .009), longitudinal hippocampal atrophy ( t 858 = 2.48; P = .01), and longitudinal decline in memory ( t 1629 = 4.09; P t 1616 = 3.00; P = .003). Vascular endothelial growth factor interacted with tau in predicting longitudinal hippocampal atrophy ( t 845 = 4.17; P t 1610 = 2.49; P = .01), and executive function decline ( t 1597 = 3.71; P t 1618 = −2.53; P = .01). Conclusions and Relevance Elevated cerebrospinal fluid VEGF was associated with more optimal brain aging in vivo . The neuroprotective effect appeared strongest in the presence of enhanced AD biomarkers, suggesting that VEGF may be particularly beneficial in individuals showing early hallmarks of the AD cascade. Future work should evaluate the interaction between VEGF expression in vitro and pathologic burden to address potential mechanisms.
Vocal-Motor and Auditory Connectivity of the Midbrain Periaqueductal Gray in a Teleost Fish

The midbrain periaqueductal gray (PAG) plays a central role in the descending control of vocalization across vertebrates. The PAG has also been implicated in auditory-vocal integration, although its precise role in such integration remains largely unexplored. Courtship and territorial interactions in plainfin midshipman fish depend on vocal communication, and the PAG is a central component of the midshipman vocal-motor system. We made focal neurobiotin injections into the midshipman PAG to both map its auditory-vocal circuitry and allow evolutionary comparisons with tetrapod vertebrates. These injections revealed an extensive bidirectional pattern of connectivity between the PAG and known sites in both the descending vocal-motor and the ascending auditory systems, including portions of the telencephalon, dorsal thalamus, hypothalamus, posterior tuberculum, midbrain, and hindbrain. Injections in the medial PAG produced dense label within hindbrain auditory nuclei, whereas those confined to the lateral PAG preferentially labeled hypothalamic and midbrain auditory areas. Thus, the teleost PAG may have functional subdivisions playing different roles in vocal-auditory integration. Together the results confirm several pathways previously identified by injections into known auditory or vocal areas and provide strong support for the hypothesis that the teleost PAG is centrally involved in auditory-vocal integration.
Half a Century of “The Nuclear Matrix”

A cell fraction that would today be termed “the nuclear matrix” was first described and patented in 1948 by Russian investigators. In 1974 this fraction was rediscovered and promoted as a fundamental organizing principle of eukaryotic gene expression. Yet, convincing evidence for this functional role of the nuclear matrix has been elusive and has recently been further challenged. What do we really know about the nonchromatin elements (if any) of internal nuclear structure? Are there objective reasons (as opposed to thinly veiled disdain) to question experiments that use harsh nuclear extraction steps and precipitation-prone conditions? Are the known biophysical properties of the nucleoplasm in vivo consistent with the existence of an extensive network of anastomosing filaments coursing dendritically throughout the interchromatin space? To what extent may the genome itself contribute information for its own quarternary structure in the interphase nucleus? These questions and recent work that bears on the mystique of the nuclear matrix are addressed in this essay. The degree to which gene expression literally depends on nonchromatin nuclear structure as a facilitating organizational format remains an intriguing but unsolved issue in eukaryotic cell biology, and considerable skepticism continues to surround the nuclear matrix fraction as an accurate representation of the in vivo situation.
Sterol carrier protein-2 mediated cholesterol esterification in transfected L-cell fibroblasts.

The relative function of the 15 and 13.2 kDa forms of SCP-2 in cholesterol trafficking and metabolism was assessed using L-cell fibroblasts permanently transfected with the cDNA encoding for either the mouse 15 kDa or 13.2 kDa SCP-2. Expression of the 15 kDa, but not the 13.2 kDa SCP-2 increased [3H]cholesteryl ester formation from medium derived cholesterol by 30% compared to control cells. In both SCP-2 expressing cell lines, sphingomyelinase treatment increased the initial rate of [3H]cholesteryl ester formation from plasma membrane derived cholesterol more than 11-fold and elevated [3H]cholesteryl ester levels 1.5-fold compared to control cells. Expression of both proteins resulted in nearly a 1.5-fold increase in [3H]oleic acid esterification into cholesteryl esters, although [3H]oleic acid esterification into triacylglycerols was also increased in the 13.2 kDa SCP-2 expressing cells relative to control. In both transfected cell lines, the cholesteryl ester mass was increased nearly 2-fold compared to control cells, consistent with increased cholesteryl ester synthesis. Similarly, triacylglycerol levels were increased 1.3-fold in the 13.2 kDa SCP-2 expressing cells which is consistent with the increased [3H]oleic acid esterification into triacylglycerol. In the 15 kDa SCP-2 expressing cells, triacylglycerol levels were decreased 60%, but free cholesterol levels were increased 1.2-fold relative to control cells. Thus, only the 15 kDa expression product, containing the putative targeting sequence, specifically enhanced cholesteryl ester formation from either plasma membrane or medium-derived cholesterol. In contrast, the 13.2 kDa expression product, lacking the putative targeting sequence, stimulated an increase in [3H]oleic acid esterification into both cholesterol and triacylglycerol pools, suggesting a non-specific stimulation of fatty acid esterification. © 1997 Elsevier Science B.V. All rights reserved.
The DDE motif in RAG-1 is contributed in trans to a single active site that catalyzes the nicking and transesterification steps of V(D)J recombination

The process of assembling immunoglobulin and T-cell receptor genes from variable (V), diversity (D), and joining (J) gene segments, called V(D)J recombination, involves the introduction of DNA breaks at recombination signals. DNA cleavage is catalyzed by RAG-1 and RAG-2 in two chemical steps: first-strand nicking, followed by hairpin formation via direct transesterification. In vitro, these reactions minimally proceed in discrete protein-DNA complexes containing dimeric RAG-1 and one or two RAG-2 monomers bound to a single recombination signal sequence. Recently, a DDE triad of carboxylate residues essential for catalysis was identified in RAG-1. This catalytic triad resembles the DDE motif often associated with transposase and retroviral integrase active sites. To investigate which RAG-1 subunit contributes the residues of the DDE triad to the recombinase active site, cleavage of intact or prenicked DNA substrates was analyzed in situ in complexes containing RAG-2 and a RAG-1 heterodimer that carried an active-site mutation targeted to the same or opposite RAG-1 subunit mutated to be incompetent for DNA binding. The results show that the DDE triad is contributed to a single recombinase active site, which catalyzes the nicking and transesterification steps of V(D)J recombination by a single RAG-1 subunit opposite the one bound to the nonamer of the recombination signal undergoing cleavage (cleavage in trans). The implications of a trans cleavage mode observed in these complexes on the organization of the V(D)J synaptic complex are discussed.
Haptic interactions with under-actuated robots using virtual mechanisms

Haptic interactions with computer generated simulations has become almost routine in Virtual Reality (VR) applications. While general interaction requires six degrees of freedom, some haptic devices are designed with fewer degrees of freedom, and so have problems representing general haptic contact. In this work, we present a new approach to the control of a general haptic device, and extend this approach to compensate for missing forces in under-actuated haptic devices. We present an experimental implementation using one of the most popular devices, the PHANTOMreg, and show experimental results for a simple case of haptic interaction.
Toward a new blood vessel

Strategies to treat atherosclerotic coronary artery disease include coronary artery bypass grafting (CABG), in which grafts are used to bypass atherosclerotic vessels and restore blood flow to the ischemic myocardium. The grafts used include healthy arteries or veins harvested from a separate site. Results with arterial grafts have been superior to venous grafts; promoting the practice of total arterial revascularization using only arterial grafts. Suitable arterial grafts, however, are scarce and harvest procedures add to morbidity and cost. Tissue engineering combines the principles of engineering with life sciences for the development of biological substitutes and restore, maintain or improve tissue function. Advances in this field have included the development of tissue-engineered blood vessels, with the potential to serve as arterial grafts, conduits or fistulae. This review describes the history of tissue engineering arteries, the techniques used, and progress to date. The source of cells and the future direction of this field are explored.
Europort-D: parallel computing for European industry

The paper discusses the highly successful European Esprit initiative Europort. The initiative migrated 35 industrial codes to parallel platforms in a portable way, covering almost the whole spectrum of industrial applications for which HPC is essential. Where costly high-computing power was the main bottleneck for numerical simulation, the availability of parallel software now allows a substantial step forward. The paper considers the follow up project Europort-D, managed by the Institute for Algorithms and Scientific Computing (SCAI) of the German National Research Center of Information Technology (GMD). For ten different application areas, new end users have demonstrated the business benefits parallel-computing technology can provide for their industry.
A comparison of the use of text summaries, plain thumbnails, and enhanced thumbnails for Web search tasks

We introduce a technique for creating novel, enhanced thumbnails of Web pages. These thumbnails combine the advantages of plain thumbnails and text summaries to provide consistent performance on a variety of tasks. We conducted a study in which participants used three different types of summaries (enhanced thumbnails, plain thumbnails, and text summaries) to search Web pages to find several different types of information. Participants took an average of 67, 86, and 95 seconds to find the answer with enhanced thumbnails, plain thumbnails, and text summaries, respectively. As expected, there was a strong effect of question category. For some questions, text summaries outperformed plain thumbnails, while for other questions, plain thumbnails outperformed text summaries. Enhanced thumbnails (which combine the features of text summaries and plain thumbnails) had more consistent performance than either text summaries or plain thumbnails, having for all categories the best performance or performance that was statistically indistinguishable from the best.
Reactions of urea phosphate in calcareous and alkaline soils: I. Ammonia volatilization

Abstract Nitrogen (N) loss in the form of volatilized ammonia (NH3) is a considerable problem when ammonium (NH4 +) forming fertilizers are applied to calcareous or alkaline soils. The volatilization of NH3 from urea phosphate (UP) and urea (U) was studied on three selected soils (Hayhook SL, Laveen L, and Latene L) with the use of a laboratory aeration system. Urea phosphate and U were each applied at rates of 0, 50, 100, and 200 mg N kg‐1 soil, either to the surface dry or in solution or mixed with the soil. The volatilized NH3 was trapped in sulfuric acid, sampled periodically, and analyzed for N with the semi microkjeldahl distillation apparatus. The highest N loss in the form of NH3 occurred when U was applied to Hayhook soil (neutral to acidic, coarse textured, and low CaCO3 content). However, UP applied to Hayhook soil resulted in the lowest NH3‐N loss. Less NH3‐N loss was found from U application to Laveen and Latene soils (fine textured with higher CaCO3 content) than with Hayhook soil. The gener...
Interface-tracking and interface-capturing techniques for finite element computation of moving boundaries and interfaces

We provide an overview of some of the interface-tracking and interface-capturing techniques we developed for finite element computation of flow problems with moving boundaries and interfaces. This category of flow problems includes fluid–particle, fluid–object and fluid–structure interactions; free-surface and two-fluid flows; and flows with moving mechanical components. Both classes of techniques are based on stabilized formulations. The interface-tracking techniques are based on the deforming-spatial-domain/stabilized space–time (DSD/SST) formulation, where the mesh moves to track the interface. The interface-capturing techniques, developed primarily for free-surface and two-fluid interface flows, are formulated typically over non-moving meshes, using an advection equation in addition to the flow equations. The advection equation governs the evolution of an interface function that marks the location of the interface. We also highlight some of the methods we developed to increase the scope and accuracy of these two classes of techniques.
Accelerated Search Kinetics Mediated by Redox Reactions of DNA Repair Enzymes

A charge transport (CT) mechanism has been proposed in several articles to explain the localization of base excision repair (BER) enzymes to lesions on DNA. The CT mechanism relies on redox reactions of iron-sulfur cofactors that modify the enzyme's binding affinity. These redox reactions are mediated by the DNA strand and involve the exchange of electrons between BER enzymes along DNA. We propose a mathematical model that incorporates enzyme binding/unbinding, electron transport, and enzyme diffusion along DNA. Analysis of our model within a range of parameter values suggests that the redox reactions can increase desorption of BER enzymes not already bound to lesions, allowing the enzymes to be recycled—thus accelerating the overall search process. This acceleration mechanism is most effective when enzyme copy numbers and enzyme diffusivity along the DNA are small. Under such conditions, we find that CT BER enzymes find their targets more quickly than simple passive enzymes that simply attach to the DNA without desorbing.
Practitioner's Research: A Study in Changing Preservice Teachers’ Conceptions About Mathematics and Mathematics Teaching and Learning

Educators involved in the current reform movement in mathematics education recommend that students be actively involved in constructing their own knowledge and developing powerful mathematical concepts. This study suggests how ideas based on constructivist learning theory can be put into practice in a preservice mathematics education class.