cssi/SciSciGPT-SciSciNet huggingface dataset:
High-frequency data reveal differential dissolved and suspended solids behavior from a mixed restored prairie and agricultural catchment

Quantifying temporal variability and fluxes within hydrologic catchments is critical to understanding the underlying chemical and physical processes leading to material transport. Measuring variability and fluxes requires sampling at time scales similar to the time scale of process occurrence. This demand has led to the development of automated sampling systems designed to sample at high frequencies, on the order of minutes. While widely deployed in a variety of systems, we installed two high-frequency sampling devices in a single drainage comprised of restored prairie and agricultural land uses in temperate Eastern Nebraska. The sampling systems determined flow rate, conductivity, and turbidity at 15-minute intervals for a twelve-month period. Conductivity was used as a proxy for total dissolved solids (TDS) concentrations and turbidity was used as a proxy for total suspended solids (TSS) concentrations. Using the high-frequency data, estimates of solids flux were calculated, error on the estimates was constrained, the effects of sample timing were considered, and conductivity and turbidity changes during precipitation events were examined. Overall, TDS fluxes were about three times higher than TSS fluxes from the catchment as a whole. However, the TSS fluxes were higher in the agricultural section of the catchment than from the restored prairie. Sheet and rill soil loss estimates from both the restored prairie and agricultural settings were low (<0.060 mm/yr). For TDS flux calculations, sampling at a monthly frequency gave a value that was only 11% lower than sampling every 15 min. For TSS flux calculations, sampling only during precipitation events (0.7% of the time) would capture 67% of the annual flux. Thus, minimizing error in sampling strategies depends on the constituent being analyzed.
Vascularized Bone Grafts for Spinal Fusion-Part 3: The Occiput.

Background Obtaining successful arthrodesis at the craniocervical junction and atlantoaxial joint can be more challenging than in other segments of the cervical spine. This challenge stems from the relatively hypermobile joints between the occipital condyles, the motion that occurs at C1 and C2, as well as the paucity of dorsal bony surfaces for posterior arthrodesis. While multiple different techniques for spinal fixation in this region have been well described, there has been little investigation into auxiliary methods to improve fusion rates. Objective To describe the use of an occipital bone graft to augment bony arthrodesis in the supraaxial cervical spine using a multidisciplinary approach. Methods We review the technique for harvesting and placing a vascularized occipital bone graft in 2 patients undergoing revision surgery at the craniocervical junction. Results The differentiation from nonvascularized bone graft, either allograft or autograft, to a bone graft using vascularized tissue is a key principle of this technique. It has been well established that vascularized bone heals and fuses in the spine better than structural autogenous grafts. However, the morbidity and added operative time of harvesting a vascularized flap, such as from the fibula or rib, precludes its utility in most degenerative spine surgeries. Conclusion By adapting the standard neurosurgical procedure for a suboccipital craniectomy and utilizing the tenets of flap-based reconstructive surgery to maintain the periosteal and muscular blood supply, we describe the feasibility of using a vascularized and pedicled occipital bone graft to augment instrumented upper cervical spinal fusion. The use of this vascularized bone graft may increase fusion rates in complex spine surgeries.
Constructing Public Space: Embodiment and Emplacement

Classic notions of public life and public space, grounded in the importance of tangible bodies in physical spaces (and their interrelationships), have been complicated by new adjacencies and connectivities afforded by digital technologies. Public space, and public bodies, increasingly take the form of cyborg entities, with the intermeshing and interaction of biological and technological components and actors, introducing new notions of citizenship and of agency in the performance of public life and the co-construction of public space, as well expanded apparatuses of control over the public realm and of empowerment of individuals and publics.
Emotion Differentiation and Youth Mental Health: Current Understanding and Open Questions.

A growing body of research identifies emotion differentiation—the ability to specifically identify one’s emotions—as a key skill for well-being. High emotion differentiation is associated with healthier and more effective regulation of one’s emotions, and low emotion differentiation has been documented in several forms of psychopathology. However, the lion’s share of this research has focused on adult samples, even though approximately 50% of mental disorders onset before age 18. This review curates what we know about the development of emotion differentiation and its implications for youth mental health. I first review published studies investigating how emotion differentiation develops across childhood and adolescence, and studies testing relations between emotion differentiation and mental health in youth samples. Emerging evidence suggests that emotion differentiation actually falls across childhood and adolescence, a counterintuitive pattern that merits further investigation. Similarly, several studies find relations between emotion differentiation and youth mental health, but some instability in results emerged. I then identify open questions that currently limit our understanding of emotion differentiation, including (i) lack of clarity as to the valid measurement of emotion differentiation, (ii) potential third variables that could explain relations between emotion differentiation and mental-health (e.g., mean negative affect, IQ, personality, and circularity with outcomes), and (iii) lack of clear mechanistic models regarding the development of emotion differentiation and how it facilitates well-being. I conclude with a discussion of future directions that can address open questions and work towards interventions that treat (or even prevent) psychopathology.
Olfaction and Physical Functioning in Older Adults: A Longitudinal Study

Background Poor olfaction is associated with worse functional performance in older adults, but longitudinal evidence is lacking. We investigated poor olfaction in relation to longitudinal changes in physical functioning among community-dwelling older adults. Methods The analysis included 2,319 participants from the Health, Aging and Body Composition Study (aged 71-82 years, 47·9% men, and 37·3% blacks) who completed the Brief Smell Identification Test in 1999-2000. Olfaction was defined as good (test score 11-12), moderate (9-10), or poor (0-8). Physical functioning was assessed up to four times over 8 years, using the Short Physical Performance Battery (SPPB) and the Health ABC Physical Performance Battery (HABCPPB). We conducted joint model analyses and reported the differences in annual declines across olfaction groups. Results During the follow-up, compared to those with good olfaction, older adults with poor olfaction had greater annual declines in both the SPPB score (-0.137, 95%CI: -0.186, -0.088) and all its subscales: standing balance (-0.068, 95%CI:-0.091, -0.044), chair stand (-0.046, 95%CI: -0.070, -0.022), and gait speed (-0.022, 95%CI: -0.042, -0.001). A similar observation was made for the HABCPPB score (difference in annual decline: -0.032, 95%CI:-0.042, -0.021). These findings are robust and cannot be explained by measured confounding from demographics, lifestyle factors, chronic diseases, nor by potential biases due to death and loss of follow-up. Similar associations were observed across subgroups of sex, race, and self-reported general health status. Conclusion This study provides the first epidemiological evidence that poor olfaction predicts a faster decline in physical functioning. Future studies should investigate potential mechanisms.
The Iron Age

Historians claim that the Iron Age began between 1500 and 1000 B.c. (at least in some parts of the world). This does not mean that iron was unknown to man before that time; quite the contrary is the case. Meteoric iron (which has a large nickel content) must have been used by prehistoric people as early as 4000 B.c. They made tools and weapons from it by shaping and hammering. It is thus quite understandable that in some ancient languages the word for iron meant “metal from the sky”. Naturally, the supply of meteoric iron was limited. Thus, stone, copper, and bronze were the materials of choice at least until the second millennium B.c. There were, however, some important uses for iron ores during the Bronze Age and also during the Chalcolithic period. As explained already in Chapter 1, copper needs a fluxing agent for the smelting process when using malachite. For this, iron oxide was utilized, which was known to react during smelting with the unwanted sand particles that are part of malachite. Eventually, a slag was formed which could be easily separated from the copper after the melt had cooled down.
Changes in the concentration and fatty acid composition of phosphoinositides induced by hormones in hepatocytes.

Abstract The hormonal regulation of phosphoinositide levels in isolated hepatocytes was studied using chemical means. Extracted inositol phospholipids were adsorbed to neomycin-coated glass beads and then eluted and quantitated by charring after separation by thin layer chromatography on silica gel. The amounts (in nanograms/mg wet weight) of phosphatidylinositol 4,5-bisphosphate (PIP2), phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol (PI) were 20 +/- 1, 16 +/- 1, and 1790 +/- 140, respectively). Incubation of the cells with 100 nM vasopressin decreased the value for PIP2 to 10 +/- 0.2 at 15 s, 12 +/- 1.5 at 1 min, and 14 +/- 2.1 at 5 and 30 min. In contrast, the hormone increased 1,2-diacylglycerol plus phosphatidate by over 200 ng/mg wet weight at 5 min under similar conditions (Bocckino, S. B., Blackmore, P. F., Wilson, P. B., and Exton, J. H. (1987) J. Biol. Chem. 262, 15309-15315). PIP2 was also significantly decreased at 15 s by angiotensin II (100 nM), ATP (100 microM), and epinephrine (1 microM). In contrast, PIP was not significantly changed, and PI was significantly decreased (by approximately 15%) at later times (15 and 30 min). The changes in phosphoinositide mass were well correlated with changes in labeled phosphoinositides in hepatocytes previously incubated with [3H]inositol for 90 min. The amounts of inositol phospholipids in liver plasma membranes (in micrograms/mg protein) were 2.1 +/- 0.2 for PIP2, 0.24 +/- 0.03 for PIP, and 23 +/- 4 for PI. Comparison of these values with those for whole cells suggests that PIP2 is enriched in the plasma membrane, whereas PIP is present elsewhere in the cell. The fatty acid composition of whole cell PIP2 showed significant differences from that of PI. The percentages of palmitic, stearic, linoleic, and arachidonic acids were, respectively, 14, 41, 10, and 25 for PIP2 and 10, 34, 7, and 37 for PI. Vasopressin treatment for 15 s did not alter the fatty acid composition of PIP2. The corresponding fatty acid percentages for liver plasma membranes were 13, 41, 11, and 21 for PIP2 and 8, 34, 0, and 40 for PI. The fatty acid composition of PIP in whole cells and plasma membranes resembled that of PIP2.(ABSTRACT TRUNCATED AT 400 WORDS)
Downscaling precipitation or bias-correcting streamflow? Some implications for coupled general circulation model (CGCM)-based ensemble seasonal hydrologic forecast

[1] The progress in forecasting seasonal climate by using coupled atmosphere-ocean-land general circulation models (CGCMs) has increased the use of CGCM-based hydrologic forecasting in recent years. A common procedure is to downscale the meteorological forcings and use them as inputs to hydrologic models to provide ensemble forecasts. Less attention has been paid to bias correcting the hydrologic forecasts directly generated by CGCM. In this study, we show that either downscaling precipitation for hydrologic model or directly bias-correcting CGCM streamflow increases the efficiency skill score greatly as compared to the original CGCM streamflow forecast, and bias correcting the streamflow from hydrologic model with downscaled precipitation leads to a further skill increase. Bias-correcting CGCM streamflow is more skillful and reliable than downscaling precipitation for hydrologic modeling in terms of ensemble forecasts, as verified by the ranked probability skill score and the rank histogram. While bias-correcting streamflow from CGCM can provide useful forecasts, combining the downscaled CGCM forcings and bias-corrected hydrologic output through the CGCM-hydrology forecasting approach does gain additional skill of accuracy and discrimination.
A Faith-Based Advantage? Comparing the Academic and Fundraising Performance of Sectarian and Nonsectarian Nonprofit Schools in Milwaukee's School Voucher Program.

This study explored whether religiously affiliated nonprofit schools participating in Milwaukee's long-standing school voucher program engage in more fundraising and perform better on academic indicators than nonsectarian nonprofit schools. The analysis of three years of organizational-level voucher school data reveals that a higher percentage of religious affiliated schools engage in fundraising, and that religious schools affiliated with umbrella organizations have higher test score indicators than nonsectarian schools. The author concludes that the religious advantage is likely in part a result of the broader access to networks and resources available to religious schools associated with umbrella organizations like a Catholic archdiocese or Lutheran synod. The results are relevant to policymakers who are considering implementing a reinvented government approach to the provision of public goods, as well as leaders of nonprofit corporations who seek to maximize performance.
Value-added benefits of technology: e-procurement and e-commerce related to the health care industry.

Purpose – To provide insights into the current supply chain for original equipment manufacturers (OEM) in the radiology diagnostic imaging equipment business. As is common in many manufacturing and service firms, the rationale of bridging suppliers of OEMs is the ability to leverage technology, software, and accessories pertaining to the various pieces of equipment.Design/methodology/approach – Several models of e‐procurement and e‐commerce related to the health care industry are presented.Findings – Although the radiology capital equipment market presents numerous idiosyncrasies that must be addressed to successfully implement an e‐business strategy effectively, incredible opportunities exist all along the supply chain for e‐business strategies to both eliminate costs and acquire strategic initiatives. Those firms that most successfully listen to their customers and address the barriers to efficiency (B2E) will help move the industry toward more effective utilization of the benefits e‐business can create...
EasyVPN: IPsec Remote Access Made Easy

Telecommuting and access over a Wireless LAN require strong security at the network level. Although IPsec is well-suited for this task, it is difficult to configure and operate a large number of clients. To address this problem, we leverage the almost universal deployment and use of web browsers capable of SSL/TLS connections to web servers and the familiarity of users with such an interface. We use this mechanism to create configurations and certificates that will be downloaded to the user's machine and be used by a program to perform all configuration on the user's system.Our system builds on common security protocols and standards such as IKE, X.509, and SSL/TLS to provide users with a secure-access environment that "just works." One of the main goals of the system is ease of use both for the users and the system administrators that maintain the infrastructure. We describe our implementation that uses Linux FreeS/WAN and Windows to show the practicality of the approach.
Electron Energy Gaps in a One-Dimensional Liquid

The method of Faulkner and Korringa is applied to a one-dimensional liquid in which the atomic potentials are $\ensuremath{\delta}$ functions and the distances between neighboring atoms satisfy a Gaussian distribution. It is shown that an energy gap exists if $\ensuremath{\sigma}$, the standard deviation in the Gaussian distribution, is small enough. The behavior of the energy gaps as $\ensuremath{\sigma}$ is varied agrees very well with the numerical results of Makinson and Roberts.
A comparative analysis of the usage and infusion of wiki and non-wiki-based knowledge management systems

Antecedents of adoption and diffusion in time-honored models such as the technology acceptance model and innovation diffusion theory may not provide sufficient measures for newer Web 2.0 technologies such as wikis. This research examines two potential extensions to the basic tenets of user acceptance: reciprocity expectation and personal innovativeness in information technology (IT). The research also examines an advancing technology: wiki technology-based knowledge management systems. Based on the results of an online survey, partial least squares analysis is used to evaluate the proposed model and provide comparative results for traditional knowledge management systems and wikis. Of the 170 respondents, 46 indicated wiki-based systems as their primary knowledge management system, while 124 indicated non-wiki-based systems as the primary system. The results indicate the set of factors influencing usage are different than the factors influencing infusion. Further, non-wiki-based versus newer wiki-based knowledge management systems have different sets of factors affecting usage and infusion. Both extensions to the base model have a greater impact on wiki-based systems as opposed to non-wiki-based systems. Reciprocity expectation was found to have a contradictory significant negative influence on infusion of wikis. Additionally, personal innovativeness in IT moderates the usage and infusion of wikis more so than for traditional knowledge management systems. These results support a more robust model for analyzing the utilization of such technologies.
Regulation of lipid droplets by autophagy

Autophagy is a lysosomal pathway by which intracellular organelles and proteins are degraded to supply the cell with energy and to maintain cellular homeostasis. Recently, lipid droplets (LDs) have been identified as a substrate for macroautophagy. In addition to the classic pathway of lipid metabolism by cytosolic lipases, LDs are sequestered in autophagosomes that fuse with lysosomes for the breakdown of LD components by lysosomal enzymes. The ability of autophagy to respond to changes in nutrient supply allows the cell to alter LD metabolism to meet the cell's energy demands. Pathophysiological changes in autophagic function can alter cellular lipid metabolism and promote disease states. Autophagy therefore represents a new cellular target for abnormalities in lipid metabolism and accumulation.
Hemispheric malformations of cortical development: surgical indications and approach

Introduction The term “hemispheric malformation of cortical development” (MCD) has come into the medical lexicon in the past 20 years as improvements and availability of advanced imaging techniques have permitted more precise diagnosis of a variety of brain developmental disorders that affect large regions of brain. These conditions are united by their propensity to elicit seizures that are difficult to control with medication in the children who suffer them.
Personality traits function as causal concepts

Abstract Traits can be either descriptive or causal, summarizing people and behavior, or explaining behavior. We hypothesized that isolated traits are primarily causal. Participants made rapid judgments of causal relations between 128 word pairs, including 32 trait-action pairs. Fenker, Waldmann, and Holyoak (2005) showed that causal relations are identified faster when words appear in a predictive sequence (cause → effect) than in a diagnostic sequence (effect → cause). They hypothesized that this occurs because causes always occur before effects. However traits are always inferred after behavioral observations. Nevertheless, if they are causally linked, participants may identify predictive sequences (clumsy → stumble) faster than diagnostic sequences (blush → shy). Participants did just that, and just as strongly as for nonsocial causes, suggesting that traits are primarily causal concepts.
Residential mobility and personal well-being

This research examines the relationship between personal mobility rate (number of lifetime moves/respondent's age) and health status. A contextual analysis is proposed in which the health consequences of relocation depend not only on the immediate circumstances surrounding a move, but also on the broader context of the individual's residential history, current life situation, and aspirations for the future. Two hundred and forty-two adult employees completed an initial survey of lifetime residential history, current residential desirability, employment experience, and perceived housing options for the future. Three months later, a panel group of 121 respondents completed a follow-up survey of emotional and physical well-being. Frequent relocation was directly associated with a greater number of illness-related symptoms, but the impact of mobility rate was largely mediated by psychological factors. Health problems were more prevalent among high-mobility individuals characterized by low rather than high levels of environmental exploratory tendency; among low-mobility persons reporting low versus high levels of residential choice and congruence; and among low residential-quality individuals who perceived future residential options to be unavailable rather than available.
Ab initio and density functional theory study of the diazene isomerization

Abstract The HF, MP2, QCISD(T), G1, G2, and G2MP2 ab initio and twenty-two density functional theory (DFT) methods were used to perform the computational studies of the syn - and cis -diazene ransformation into trans -diazene. In all calculations the Gaussian type 6–311 + G(2d,2p) basis set was used. The DFT computed geometries and energies are compared with ab initio results and the validity of several DFT methods for studying this and similar molecular systems are evaluated.
Tracking by young infants.

Tracking by infants aged 8–28 weeks is shown to be supported by the displacement of an object relative to a background. When object and background move together tracking is disrupted. This disruption in tracking is shown to be due to the absence of relative displacement between object and background and not to movement of the background as such. The absence of relative displacement reduces the duration of pursuit but does not alter the frequency of target-capture.
The human GCAP1 and GCAP2 genes are arranged in a tail-to-tail array on the short arm of chromosome 6 (p21.1).

GCAP1 and GCAP2 are related Ca{sup 2+}-binding proteins that activate photoreceptor guanylate cyclase(s). We showed previously that the human GCAP1 gene, consisting of four exons, is located at 6p21.1 (locus designation GUCA). To identify the chromosomal location of the GCAP2 gene, we first cloned its cDNA and determined its intron-exon distribution by PCR analysis. The results show that the introns of the GCAP2 gene are positioned exactly as in the GCAP1 gene and are nearly double in size. Sequence similarity between the two genes, however, is limited to portions of exons 1 and 2. The GCAP1 and GCAP2 genes are transcribed into single mRNA species (1.7 and 2.2 kb, respectively) and are detectable only in the retina by Northern blotting. The GCAP2 gene was found by somatic human-hamster hybrid panel analysis and FISH to reside at GUCA in a region indistinguishable from that of GCAP1. PCR analysis with exon 4-specific primers showed that the genes are in a tail-to-tail array less than 5 kb apart and altogether span less than 20 kb of genomic DNA. The identical gene structures and loci of GCAP1 and GCAP2, and the identical function of the gene products, are consistent with a gene duplication event.more » 42 refs., 7 figs.« less
How Many Protein Folding Motifs are There

Abstract As the three-dimensional structures of more and more proteins are determined by experiment, discovering substantially novel folding motifs becomes ever rarer. The natural question is how many motifs are there and how many have already been found? In order to answer this in at least one plausible and well-defined sense, we have chosen a quantitative measure of conformational similarity, ρ (based on optimal rigid body superposition), and a means of generating all possible three-dimensional chain conformations using the discrete cosine transform. How many different folding motifs there are then depends on the specified cutoff in ρ and on the flexibility allowed for the model polypeptide chain. For single chain proteins having no more than about 170 residues and which are not β-barrellllllls, there are only about 128 motifs that differ by ρ>1.0 (an extremely vague level of similarity), of which so far only 100 have been seen experimentally. The remaining 28 can be viewed as very low-resolution models of either undiscovered novel folds or violations of unknown principles of protein folding.
Scaling behavior in the scratching of automotive clearcoats

The scratch resistance of four clearcoat formulations was evaluated using a CSM nano-scratch tester, an AMTEC-Kistler simulated carwash tester, and a laboratory scale macro-scratching tester. Significant differences in the rank-order of all the clearcoats were found when comparing the scratch and mar behavior using macro-scratching, nano-scratching, and AMTEC-Kistler testing. Field vehicles were also examined where the mean and median widths of scratches found on vehicles were 237 and 141 μm, respectively. The range of loads associated with events with the potential to create real-world scratches was found to be significantly higher (5–35 N) than the forces needed to make scratches of the same mean size as those seen in the field (7–10 N). These results indicated that a significant improvement in the scratch resistance of these clearcoats would be needed before customers would notice improvements in their paint finish’s scratch resistance.
Preparation of radioactively labeled monodisperse silica spheres of colloidal size.

Abstract A recently developed technique of growing monodisperse silica spheres of predetermined size in alcoholic solutions facilitates the incorporation of certain radioactive tracers. Spheres growing to a final diameter of 8 × 10 −5 cm were used in a study with radioactive isotopes including 7 Be, 51 Cr, 54 Mn, 58 Co, 59 Fe, 65 Zn, 124 Sb, 134 Cs, and 141 Ce. The results reveal that those metals which form oxides of low solubility at pH ≥ 7 are easily incorporated into the bulk of the silica spheres when present during the growth of the particles in an amount not exceeding 1–10 ppm with respect to the total mass of silica in the system.
Transient alterations of the QRS complex and ST segment during percutaneous transluminal balloon angioplasty of the left anterior descending coronary artery.

Using continuous 3-lead electrocardiographic (ECG) recordings in 19 patients undergoing elective percutaneous transluminal coronary artery angioplasty (PTCA) of the left anterior descending (LAD) artery, this study described the dynamic changes of the ST segment and the R- and S-wave amplitudes that occur during transient myocardial ischemia. The waveforms from lead V2 were quantified at 10-second intervals during the length of the balloon inflation that produced the greatest extent of ST-segment deviation. The simultaneous changes that occurred in leads a VF and V5 were also observed, but not quantified. Measurements of R- and S-wave amplitudes were performed during maximal ischemia from both the PR- and the J-ST-segment baselines to determine which of these most nearly maintained its control position during ischemia. The results indicate that the R-wave amplitude is best determined from the PR-segment baseline (p = 0.0007), while the S wave is best determined from the J-ST-segment baseline (p = 0.03). However, only a portion of the QRS changes observed during PTCA could be accounted for by the baseline shift. There were additional QRS changes during ischemia in 11 of the patients (58%) suggestive of conduction disturbances in 3 endocardial sites: left septal, right septal and left anterosuperior. It is hypothesized that these changes may represent ischemia-induced delay in conduction (“periischemic block”) previously thought to occur only with myocardial infarction.
Recruitment Contrasts in a Divided Charismatic Movement

This research report analyzes the evolution of the bond between a charismatic leader and his mass following. Its empirical focus is the case of Juan Peron and the Peronist movement in Argentina. After discussing stages in the evolution of charisma, we review our earlier findings showing that by 1965 there was clear separation between those Peronists devoted to the movement and those Peronists devoted to the man. We note distinctive features in the social and attitudinal profiles of each and then turn to our principal concern, the recruitment of new blood into each Peronist camp. Personalist youth turn out to be much like their older counterparts, but organizationalist youth demonstrate social and attitudinal features that set them dramatically apart from the personalists and apart from the older organizationalists as well. We discuss the implications of this ever widening rift.
Kelvin probe microscopy measurements of surface potential change under wear at low loads

Abstract Kelvin probe microscopy has been used to detect wear precursors at ultralow loads. Samples studied include single crystal silicon (1 0 0), single crystal silicon (1 0 0) lubricated with fully bonded Z-DOL (a perfluoropolyether), gold, aluminum and alumina. The effect of load and number of cycles on surface potential change under ultralow loads has been investigated. Influence of the scan parameters and the reproducibility of the experimental results have been studied. It is found that the measured change in surface potential is strongly affected by the scan parameters as well as the shape of the probe. Negative wear depth on single crystal silicon (1 0 0), and single crystal silicon (1 0 0) lubricated with fully bonded Z-DOL during early stages of sliding has been observed. (The scratched area was raised rather than depressed as compared to the unworn surrounding region.) Chemical analysis of unworn and worn regions of silicon and silicon lubricated with fully bonded Z-DOL was performed to reveal possible mechanisms of changes in surface potential. It is believed that the removal of a thin contaminant layer, natural oxide layer or lubricant during a few wear cycles gives rise to the initial change in surface potential. It is further believed that structural changes which precede generation of wear debris and/or measurable wear scars occur under ultralow loads in the top few nanometers of the sample, which are primarily responsible for the measured changes in surface potential.
Optimal regimes of facilitated transport for multiple site carriers

Abstract In this study, two different transport models that describe multiple site carrier-mediated transport in liquid membranes were studied. The optimal dimensionless equilibrium constants were determined that yield the maximum facilitation factor (F) for given inverse Damkohler numbers (ϵ1, ϵ2), and mobility ratio (α). Facilitation factors were also calculated for given equilibrium constants (K1, K2), ϵ1, ϵ2, and α values. The existence of the maximum facilitation is demonstrated in the range of diffusion-limited to reaction-limited transport. The optimum K1, optimum K2 and corresponding values of F are plotted for a range 10−3≤ϵ1, ϵ2≤10+1 and 1≤α≤100. The optimum F increases with increasing α, decreasing ϵ1, ϵ2 and has a maximum for a range 1≤K1, K2≤10. These results are important in choosing the type of carrier and experimental conditions, and in comparing optimal with experimental results.
Tephrochronology of highly altered ash beds: the use of trace element and strontium isotope geochemistry of apatite phenocrysts to correlate K-bentonites

Tephrochronological studies of extremely altered ash beds (bentonites) are hampered by the difficulty of determining the original volcanic ash compositions. Correlations of individual Ordovician K-bentonites within the Taconic Foreland basin of the northern Appalachian orogen, however, are possible based on trace element and strontium isotopic analyses of apatite phenocrysts contained within the altered ash beds. Apatite phenocrysts from most of the K-bentonites have characteristic Cl, Fe, Mg, and Mn contents; thus, these elements are good discriminators. Rare earth element concentrations of apatite phenocrysts are not as distinct and are less useful discriminators. The strontium isotopic composition of apatite phenocrysts is the single most diagnostic parameter for distinguishing the Taconic basin K-bentonites. The range in measured 87Sr/86Sr ratios for the apatite phenocrysts from different K-bentonites is 0.7056–0.7090. Some apatite phenocrysts have undergone secondary alteration, indicated by a frosted, opaque appearance. These grains have slightly different 87Sr/86Sr ratios compared to unaltered apatites from the same K-bentonite layer collected at different localities. The cause and timing of the alteration is unknown but it may reflect interaction with fluids that equilibrated with the surrounding country rock. Exchange with seawater Sr cannot solely account for the observed effect because altered samples are displaced both toward and away from Ordovician seawater 87Sr/86Sr values. The alteration effects appear to be limited to the outer portion of the apatite grains because the effects were overcome by abrading the apatites in an air-abrasion device. Determining the 87Sr/86Sr ratios of abraded apatites may become a general method of determining the strontium isotopic composition of a wide variety of altered felsic volcanic rocks. Previous correlations of the K-bentonites within the Taconic Foreland basin were based on the physical matching of individual beds and groups of beds. These correlations led to the assertion that several graptolite species thought to be important in biostratigraphic studies were coeval and thus provided no time information. The new geochemical correlations of the K-bentonites, however, demonstrate that the graptolite zones are indeed sensitive time indicators. Many of the previous correlations are thus incorrect, and paleo-environmental models based on them need to be reevaluated.
The Nonunilineal Descent Group in the Caribbean and Central America

HUMAN social groupings have been classified by various observers in many different ways, usually according to the basis upon which individuals gain membership to the group. One large category consists of groupings based upon kinship, and included in it are such institutions as the family, the lineage, the clan, the sib, the stock, the kindred, and many others depending upon how the scientist wishes to define his terms. In this paper I wish to discuss a type of kinship grouping which has hitherto received little attention from anthropologists. Its characteristics place it outside any grouping listed above, though it has at times been confused with the kindred. Goodenough (1955:72) has pointed out that two distinct definitions of the kindred have previously appeared in the literature. In one, the kindred is seen as a group of people tracing their kinship connections laterally to a common relative. In the other, the members of the group trace descent lineally from a common ancestor. This latter group differs from such unilineal descent groups as the lineage and the clan by the fact that members trace their descent through both males and females; i.e., through either a male or a female in any given generation. Because of this characteristic, the group may be referred to as a nonunilineal descent group. Former references to this type of kinship grouping are few and, for the most part, brief. Radcliffe-Brown seems to be referring to it when he discusses "stocks" among the ancient Teutonic peoples (1950:16). In that system a stock was composed of the descendents, counted through any line, of one of Ego's four pairs of great-grandparents. Ego would thus belong to four distinct stocks. We are told nothing more of the structure and functioning of such groups, nor whether they served in any way as corporate bodies. Goodenough (1955) presented a fairly extensive discussion of the nonunilineal descent group in certain Polynesian social organizations.' He pointed out that some element other than descent must restrict and define the actual membership of each group. An individual may belong to as many such descent groups as he has ancestors, and without some other determining element such groups could never function as discrete or corporate units in a society. Goodenough (1955: 72) has suggested several ways of restricting membership which are used in various parts of Polynesia. These include restriction to (1) persons possessing certain land rights, (2) persons born in a particular area, and (3) persons who choose to reside in a given area. I shall now describe the nonunilineal descent group among the Black Carib of Central America. As in most other contemporary Caribbean societies, the
Thermal and mechanical properties of poly(lactic acid)/starch/methylenediphenyl diisocyanate blending with triethyl citrate†

Triethyl citrate (TC) was added as a plasticizer to a blend of poly(lactic acid) (PLA) and starch in the presence of methylenediphenyl diisocyanate (MDI). As expected, TC improved the elongation at break and toughness and, at the same time, decreased the tensile strength and modulus. However, TC did not significantly affect the coupling effects of MDI on starch and PLA. The tensile strength of the blend with MDI was much greater than the tensile strength without MDI at the same TC level. The tensile properties of the blend changed dramatically as the TC concentration increased from 5 to 12.5%. At a TC concentration of 7.5%, the blend produced desirable elongation and toughness with fairly good tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2947–2955, 2003
Structure of the nerve myelin membrane: Proof of the low-resolution profile

Abstract In analyzing the low-angle X-ray diffraction patterns recorded from the normal and swollen myelin in frog sciatic nerve, a precise value is found for the center-to-center distance between the pair of membranes constituting the repeating structure in the myelin. The previously reported large increase in period when the nerve is put in hypotonic Ringer's solution is shown to be accompanied by a small decrease in the center-to-center distance of the membranes within one pair. Thus both a large amplitude swelling at the extracellular interface between membrane pairs and a moderate one at the cytoplasmic interface within the pair are observed. The two kinds of swelling—cytoplasmic and extracellular—are sufficient to demonstrate crystallographically the correctness of the bilayer profile for a single myelin membrane. The existence of a lipid bilayer within the membrane is confirmed by the scale of absolute electron density derived from the swelling experiments, and hydrated surface layers of protein are postulated.
Simultaneous spectrophotometric and mechanical property characterization of skin

Both reflectance spectroscopy and the determination Young's Modulus of skin have shown promise for identifying skin pathology. At present, these determinations are carried out using separate methodologies. This study demonstrates a new technology combining digital UV/VIS reflectance spectroscopy and vacuum aspiration for simultaneously determining the reflectance spectrum and mechanical properties of human skin tissue. A small hand held prototype device incorporating fiber-optic light guides into a vacuum channel was calibrated using various elastic materials subjected to increments of stress by vacuum from 0 to 25 in Hg. The intensity of a UV/VIS light beam reflected from the material at each vacuum increment was compared to the resulting material strain. The reflected beam was also spectrophotometrically analyzed. Skin types were similarly evaluated comparing normal and scar tissue and skin of various ages and coloration. An exponential relationship between reflected beam intensity and the amount of strain resulting from vacuum increments was observed. Young's Modulus (calculated from Aoki et. al equation) and spectra from normal skin and scar tissue were in agreement with previously published observations. Age related decreases in skin elasticity were also demonstrated. In the reflectance spectra, oxy and deoxy-hemoglobin absorbance bands were detected, becoming significantly enhanced at increased levels of vacuum. Melanin absorbance was also easily detected and appeared to correlate with skin coloration. Since superficial skin pathologies have characteristic spectroscopic and mechanical properties, this technique may provide a promising new approach for rapid, non-invasive method for the evaluation of skin lesions.
Mutations affecting the binding, internalization, and lysosomal hydrolysis of low density lipoprotein in cultured human fibroblasts, lymphocytes, and aortic smooth muscle cells

Studies comparing the metabolism of low density lipoprotein (LDL) in normal cells and in cells cultured from patients with homozygous familial hypercholesterolemia have disclosed the existence of a receptor for plasma LDL. This receptor has been identified on the surface of human fibroblasts, lymphocytes, and aortic smooth muscle cells. An extension of these studies to cell strains derived from patients with other single gene defects in cholesterol metabolism has provided additional insight into the normal mechanisms by which cells regulate their cholesterol content and how alterations in these genetic control mechanisms may predispose to atherosclerosis in man.
Is excess folic acid supplementation a risk factor for autism

Abstract Background The objective was to assess the association between increasing autism incidence rates and the increasing dose of folic acid in prescription prenatal and pediatric vitamins. Methods We used published autism incidence rates from the Rochester Epidemiological Project in Rochester, MN, for 1976–1997. Additionally, we used the percent of prescription prenatal vitamins containing 1mg folic acid and the percent of prescription pediatric vitamins with any folic acid from Physicians' Desk References for roughly the same time period. Results The Pearson product moment correlation coefficient ( r ) for the association between the percentage of prescription prenatal vitamins containing 1mg folic acid and research-identified autism incidence in Olmsted County was 0.87 [95% confidence interval (CI)=0.19–0.99]. In contrast, there was a weak association between pediatric vitamins containing any folic acid and autism incidence using the same statistical method ( r =0.62, 95% CI=−0.38–0.95). Conclusions If it is true that too little folic acid results in nervous tissue damage, as is accepted by the scientific community in regard to neural tube defects (NTDs), then it seems plausible that too much folic acid may result in nervous tissue damage associated with autism. Although the correlations described here do not provide proof of causation, these data provide an impetus for further study. Children who develop autism may be receiving a massive dose of folic acid in utero, as well as, after birth. It would be of interest to carry out a case–control study using medical record data to document folic acid intake for pregnant women whose offspring were later diagnosed with autism and controls.
Velocity Redistribution in Meandering Rivers

An analytical model for calculating the lateral distribution of the depth-averaged primary flow velocity in meandering rivers is presented. A small perturbation approach is used to linearize the governing equations. The well-known “moment method,” commonly used to solve the concentration distributions, is then used to obtain an approximate solution. This makes it possible to take into account the convective transport of primary flow momentum by the secondary flow. This oft-neglected influence of the secondary flow is shown to be an important cause of the redistribution of the primary flow velocity. The model, when tested with laboratory data, gives substantially better results than several previous models.
Direct and efficient cellular transformation of primary rat mesenchymal precursor cells by KSHV

Infections by viruses are associated with approximately 12% of human cancer. Kaposi’s sarcoma-associated herpesvirus (KSHV) is causally linked to several malignancies commonly found in AIDS patients. The mechanism of KSHV-induced oncogenesis remains elusive, due in part to the lack of an adequate experimental system for cellular transformation of primary cells. Here, we report efficient infection and cellular transformation of primary rat embryonic metanephric mesenchymal precursor cells (MM cells) by KSHV. Cellular transformation occurred at as early as day 4 after infection and in nearly all infected cells. Transformed cells expressed hallmark vascular endothelial, lymphatic endothelial, and mesenchymal markers and efficiently induced tumors in nude mice. KSHV established latent infection in MM cells, and lytic induction resulted in low levels of detectable infectious virions despite robust expression of lytic genes. Most KSHV-induced tumor cells were in a latent state, although a few showed heterogeneous expression of lytic genes. This efficient system for KSHV cellular transformation of primary cells might facilitate the study of growth deregulation mechanisms resulting from KSHV infections.
White girls: avant-gardism and advertising after 1860.

James McNeill Whistler's painting The White Girl (Symphony in White, No. 1) caused a scandal for depicting a woman dressed all in white, uncontained by any clear framing narrative. Though the painting is usually read into a history of modernism for its experimental play with tones of white, in fact the painting was linked by Victorian viewers to the mass-cultural phenomenon surrounding Wilkie Collins's sensation novel The Woman in White . By examining the two works together, this article shows that the divide between the world of fine arts and that of sensational entertainment is perhaps more entrenched in our own canons than it was for Victorian spectators and consumers.