cssi/SciSciGPT-SciSciNet huggingface dataset:
Changing measurement instrument at follow-up: a potential source of error

The purpose of this investigation was to determine whether headache activity information collected over the phone can be directly compared with headache activity information collected by systematic self-observation without jeopardizing internal validity because of calibration differences between the two measurement methods. A number of headache studies have relied on phone information for long-term follow-up data, while using systematic self-observation to collect all other data. Twenty-six headache sufferers participating in a tension headache study reported their headache activity over the phone and subsequently charted their headaches. Correlations were computed between the two measures. Results indicated that differences exist in the calibration of the two measurement methods. This seriously limits the conclusions of studies that used phone information to obtain follow-up data. Other recommendations concerning follow-up methodologies are discussed.
Feeding and Fleecing the Native: How the Nyasaland Transport System Distorted a New Food Market, 1890s-1920s

Failed states in Africa are not a uniquely postcolonial phenomenon: The colonial government in Nyasaland started and ended as a failed state. Although effective in guarding Britain's global interests against her imperial rivals, the Nyasaland government could not be relied upon as a trustworthy ally of any social class within the country. The government failed to provide essential services, particularly roads, with dire consequences for both the peasant economy and European enterprises. Without a reliable road network, transport companies came to depend on the vagaries of the weather and the availability of villagers to carry goods on their heads. Transporters competed with planters and other European enterprises for cheap labour, instituting a costly freight regime that discouraged planters from raising bulky, low-value food crops. Thus, to feed their workers, all European enterprises – farmers, missionaries, traders, transport companies and the government – turned to peasant-grown food. Responding to th...
Zinc-induced anemia in young japanese quail ameliorated by supplemental copper and iron

Abstract Studies were conducted to examine whether anemia induced in newly hatched Japanese quail by moderate dietary Zn supplements could be corrected by supplemental Fe, Cu, or Mg by 14 d of age. Low hemoglobin (Hb) was partially alleviated by increased levels of Fe or Cu, but normal Hb was obtained only with Fe plus Cu. Fe and Cu concentrations in the liver were decreased at 7 d, prior to the development of anemia by 13 d. Additional Mg had no effect on low Hb caused by Zn. Copper supplementation partially alleviated the growth depression and entirely prevented the lack of feather pigmentation that resulted from Zn toxicosis. Neither Fe nor Mg affected either of these parameters. These data indicate that both Fe and Cu status of an individual may be compromised by dietary Zn supplementation.
Aflatoxin content of foods served to a population with a high incidence of hepatocellular carcinoma.

During three seasons, 36 samples of foods served to mentally retarded clients with a high incidence of hepatocellular carcinoma were analyzed for aflatoxin. Aflatoxin was not detected (less than 5 ppb) by thinlayer liquid chromatography in 35 food samples containing peanuts, corn, wheat or milk. One peanut butter sample contained 20 ppb aflatoxin. Aflatoxin content of these foods was at or below the level permitted by the Food and Drug Administration. Aflatoxin is probably not responsible for liver disease in this population.
A mechanics model for the compressive response of fiber reinforced composites

Abstract This article presents a model for the uni-axial compressive response of uni-directionally reinforced fibrous composite. The model accounts for the non-linear shear response and the failure strain of the matrix, incorporating both aspects into a non-linear field equation which governs the load-deflection process. In addition, the model considers the effects of two kinds of geometric imperfections, namely, initial fiber waviness and random fiber spacing. It is shown that, under uni-axial compression, random fiber spacing may instigate the formation of severe transverse loadings on the fibers, which suggest the existence of a transitional mechanism from micro-buckling to micro-kinking. Computational results are presented which illuminate the effects of several material and geometric factors on the compressive strength of composites.
Pricing biologics: Issues, strategic priorities and a conceptual model

The advent of complex and often expensive biologics raises critical commercial challenges – the most important of which pertains to developing a viable pricing, distribution and reimbursement model that is intrinsically geared to the special characteristics of biologic products and the expectations of a diverse customer population. Idiosyncratic differences in health-care systems, their philosophical motivations and preferred methods of controlling access to expensive biologic treatments pose additional challenges. This article discusses key issues about pricing biologics from the primary viewpoint of biologic manufacturers and marketers, focusing on the inseparable relationship between price, distribution, access and reimbursement. Specific priorities are explicated for streamlining biologic pricing and access strategies to meet upcoming challenges. A conceptual model for developing viable biologic pricing strategy is presented. Insights from the author's work implementing key aspects of the model in the real world are discussed. The article concludes by presenting an overview of a pricing decision support system that has proven invaluable in formulating and managing biologic pricing strategies over a finite time horizon.
A Turquoise Mutant Genetically Separates Expression of Genes Encoding Phycoerythrin and Its Associated Linker Peptides

During complementary chromatic adaptation (CCA), cyanobacterial light harvesting structures called phycobilisomes are restructured in response to ambient light quality shifts. Transcription of genes encoding components of the phycobilisome is differentially regulated during this process: red light activates cpcB2A2, whereas green light coordinately activates the cpeCDE and cpeBA operons. Three signal transduction components that regulate CCA have been isolated to date: a sensor-photoreceptor (RcaE) and two response regulators (RcaF and RcaC). Mutations in the genes encoding these components affect the accumulation of both cpcB2A2 and cpeBA gene products. We have isolated and characterized a new pigmentation mutant called Turquoise 1. We demonstrate that this mutant phenotype is due to a dramatic decrease in cpeBA transcript abundance and results from a lesion in the cpeR gene. However, in this mutant cpeCDE RNA levels remain near those found in wild-type cells. Our results show that the coordinate regulation of cpeBA and cpeCDE by green light can be uncoupled by the loss of CpeR, and we furnish the first genetic evidence that different regulatory mechanisms control these two operons. Sequence analysis of CpeR reveals that it shares limited sequence similarity to members of the PP2C class of protein serine/threonine phosphatases. We also demonstrate that cpeBA and cpeCDE retain light quality responsiveness in a mutant lacking the RcaE photoreceptor. This provides compelling evidence for the partial control of CCA through an as-yet-uncharacterized second light quality sensing system.
Atmospheric pressure matrix‐assisted laser desorption/ionization with analysis by ion mobility time‐of‐flight mass spectrometry

The use of an atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) source was employed with an atmospheric pressure ion mobility spectrometer (APIMS) and an orthogonal acceleration reflector time-of-flight mass spectrometer (TOFMS) to analyze dipeptide and biogenic amine mixtures from a liquid glycerol 2,5-dihydroxybenzoic acid (DHB) matrix. Improved sensitivities were obtained by the addition of a localized electrical (corona) discharge in conjunction with the AP-MALDI source. Enhanced sample ionization efficiency created by this combination provided an overall elevation in signal intensity of approximately 1.3 orders in magnitude. Combinations of three dipeptides (Gly-Lys, Ala-Lys, and Val-Lys) and nine biogenic amines (dopamine, serotonin, B-phenylethylamine, tyramine, octopamine, histamine, tryptamine, spermidine, and spermine) were resolved in less than 18 ms. In many cases, reduced mobility constants (K(o)) were determined for these analytes for the first time. Ion mobility drift times, flight times, arbitrary signal intensities, and collision-induced dissociation (CID) fragmentation product signatures are reported for each of the samples.
An iteration perturbation technique

Abstract A numerical iteration technique, which is simple to use and easy to implement, is proposed to solve perturbation problems. The technique may be used to supplement or to complement the PLK (Poincare, Lighthill, and Kuo) method. The iteration perturbation technique can solve problems for which the PLK method fails. Numerical experience with several examples is described.
Post—Functional Social Systems Analysis

This paper attempts to develop a macro social systems model devoid of the many problems which plagued functionalism. I eschew concepts such as equilibrium, survival, and functional prerequisite. In...
Internal electric energy in a spherical particle illuminated with a plane wave or off-axis Gaussian beam

The electric energy in a lossless or lossy spherical particle that is illuminated with a plane wave or a Gaussian beam is investigated. The analysis uses a combination of the plane-wave spectrum technique and the T-matrix method. Expressions for the electric energy in any mode as well as the total electric energy inside the particle are given. The amount of energy coupling into the particle for different beam illuminations is also investigated. The high-Q (low-order) resonant modes can dominate the electric energy inside a spherical particle many linewidths away from the resonance location, particularly if the beam is focused at the droplet edge or outside the droplet. If the sphere is lossy, low-order modes can still dominate the electric energy if the beam is focused far enough outside the sphere. As the absorption coefficient of the particle increases, the energy in a high-Q mode decreases much faster at the resonance frequency than it does at near or off-resonance frequencies. The effects of the absorption on the dominance of the internal fields by a high-Q mode decreases as the beam is shifted farther away from the particle. As the beam is shifted farther away from the particle the fraction of the incident energy coupled into the sphere at resonance first increases and then decreases. Although the coupled energy decreases as the beam is shifted farther from the sphere, most of that energy is in the lowest-order mode.
Factors in gaining compliance toward an acceptable level of personal unsecured debt

This paper proposes a conceptualization of factors that influence the ability of individuals to reduce their personal unsecured debt levels, especially credit card debt. As such the paper's conceptualization offers relationship lessons for bank marketers in the USA and the UK, where bank credit cards are a key element of many bank marketing programs. A key contribution is the paper's focus on customer compliance behavior in a personal unsecured debt management program. Factors discussed within our conceptualization are behavioral variables and psychological variables. Also examined is the role of geographic and demographic explanatory variables in personal debt management program success.
A New Approach to Estimate a Mixed Model-Based Ground Motion Prediction Equation

A derivative-free approach based on a hybrid genetic algorithm (HGA) is proposed to estimate a mixed model–based ground motion prediction equation (attenuation relationship) with several variance components. First, a simplex search algorithm (SSA) is used to reduce the search domain to improve the convergence speed. Then, a genetic algorithm (GA) is employed to obtain the regression coefficients and the uncertainties of a predictive equation in a unified framework using one-stage maximum-likelihood estimation. The proposed HGA results in a predictive equation that best fits a given ground motion data set. The proposed HGA is able to handle changes in the functional form of the equation. To demonstrate the solution quality of the proposed HGA, the regression coefficients and the uncertainties of a test function based on a simulated ground motion data set are obtained. Then, the proposed HGA is applied to fit two functional attenuation forms to an actual data set of ground motion. For illustration, the results of the HGA are compared with those used by previous conventional methods. The results indicate that the HGA is an appropriate algorithm to overcome the shortcomings of the previous methods and to provide reliable and stable solutions. DOI: 10.1193/1.2755934
Improved and corrected transition probabilities of argon I in the range of 5000–6000 Å

Abstract We describe the effect of revisions in the compilation of transition probabilities ( A nm ) of ArI on recently published values of A nm (for energy levels higher than 120 000cm -1 above the ground level) and on radial temperature distributions in an arc.
Electrostatic oscillations in inhomogeneous cold plasmas

Abstract A theoretical investigation of small-amplitude electrostatic oscillations in cold inhomogeneous plasmas is presented. It is demonstrated that for those systems possessing continuous nonconstant unperturbed electron-ion densities, a Fourier or normal-mode analysis in time leads in general to singular modes and a continuous frequency spectrum. Well-behaved solutions to the linearized partial differential equations describing the system are obtained by taking a Fourier integral superposition (inverse Fourier transform) of the singular modes over their continuous spectrum. The analysis leads, in particular, to the following results: 1. 1. A finite plasma with an everywhere continuous and nowhere constant plasma frequency ω p ( x ) admits of only singular modes and an entirely continuous spectrum. No dispersion relation exists. 2. 2. If, for a collision-free plasma, ω p 2 ( x ) is continuous in a region R , that region contributes to the spectrum precisely those values of ω such that ω 2 = ω p 2 ( x ) for some x in R . 3. 3. A finite plasma with an everywhere continuous ω p 2 ( x ) will resonate in the presence of an applied field, oscillating with the frequency ω, precisely at those points x of the plasma where ω p 2 ( x ) = ω 2 . 4. 4. The introduction of jump discontinuities into ω p 2 ( x ) is necessary for the existence of well-behaved modes and a discrete spectrum (dispersion relation), if ω p 2 is nowhere constant. If ω p 2 ( x ) jumps discontinuously from a value ω 1 2 to a value ω 2 2 > ω 1 2 upon crossing a surface S , and if ( ω 1 2 , ω 2 2 ) and the range of ω p 2 ( x ) have no points in common, then a well-behaved mode will exist with a frequency ω such that ω 1 2 ω 2 ω 2 2 .
Optimising outcomes: socioeconomic perspective

All medical interventions carry costs, and the economic implications are a major consideration when any change in medical practice is proposed. New drugs are often more expensive than those that they are designed to replace, and the introduction of new procedures may also entail increased costs. Medical costs include not only the cost of the drug itself, but also the induced costs (or sometimes, cost savings) such as the costs of administering the drug and the consequent levels of use of other medical resources, including medical personnel. The ESSENCE study (Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q-wave Coronary Events)—a double blind, randomised trial of the low molecular weight heparin enoxaparin and unfractionated heparin (UFH) in unstable angina and non-Q wave myocardial infarction1—addressed this issue by means of a prospectively designed economic study to evaluate the cost implications in the light of clinical outcomes.2The ESSENCE economic study was undertaken on those patients in the US, and examined both the use of medical resources and the medical costs to 30 days. The case report form used in the ESSENCE study was designed to include information on use of medical resources. Full medical billing information was available for 655 patients out of the total of 923 enrolled in the US, and a conversion factor included in each hospital’s Medicare cost report was used to convert the charges to costs. The national Medicare fee schedule was used to assign physician fees for the purposes of this analysis. Billing information was not available for 268 patients; in these cases costs were imputed using a …
Anxiety Sensitivity in Childhood and Adolescence: Parent Reports and Factors that Influence Associations with Child Reports

Research suggests that anxiety sensitivity is an important cognitive developmental precursor of anxiety disorders. Identifying the developmental origins of anxiety sensitivity may be facilitated by multiple perspective assessment (parents, children) coupled with an understanding of agreement in reporting. In general, disagreement between parent and youth ratings of the child’s emotions is common but is not well understood. Variables such as age and gender have been suggested as potential factors that influence agreement; however, this literature often produces inconsistent results. This study examined parent reports of their children’s anxiety sensitivity in order to explore the effects of age, sex, and ethnicity on cross informant associations with child reports using complementary statistical models. Parents and children (N = 202, aged 6–17 years) completed child and parent versions of the childhood anxiety sensitivity index [CASI (child) and CASI-P (parent)] as well as instruments assessing fears and manifest anxiety. Results indicated that the CASI-P demonstrated internal consistency, test–retest associations, incremental and concurrent validity estimates similar to those previously reported for the self report instrument. Moreover, reliability and validity were highly similar across age and child sex. However, age and ethnicity were found to significantly influence cross informant associations, and the statistical method used to examine cross informant associations produced differing conclusions. Results are discussed in terms of the utility of a parent report measure of anxiety sensitivity and implications of the differing statistical methods for clarifying the existing research on informant agreement in internalizing symptoms.
Accelerated healing with a mesh autograft/allodermal composite skin graft treated with silver nylon dressings with and without direct current in rats.

Purpose: Evaluation of the healing and persistence of a meshed composite skin graft applied without immunosuppression. Methods: The contraction of wounds grafted with 9:1 split-thickness autograft/1.5:1 allodermal mesh composite skin grafts (auto/allo MCSGs) was investigated. No immunosuppressive agent was applied. Male ACI rats and female Lewis rats reciprocally served as allodermis graft donors and recipients. Autograft/dermal autograft and allograft/dermal allograft MCSGs were the controls. Results:At 3 months after grafting, when epithelized auto/allo MCSG wounds were measured by computerized morphometric analysis, the silver nylon (SN) dressing group displayed less contraction than the Vaseline (petroleum jelly) dressing group (p < 0.003), and direct current treatment (SNDC) was more effective than SN (p < 0.005). The histologic structures of the hair follicles appear to confine the rejection process to the allogeneic follicles of the graft. The focal nature of the rejection process and the relatively low antigenicity of the dermal matrix allowed the survival of the allodermis layer. Although direct current significantly enhanced MCSG healing, SN and SNDC were not the immunosuppressive agents that were confirmed. Conclusion: This type of MCSG can heal without immunosuppressive treatment.
Estimation of lens distortion correction from single images

In this paper, we propose a method for estimation of camera lens distortion correction from a single image. Without relying on image EXIF, the method estimates the parameters of the correction by searching for a maximum energy of the so-called linear pattern introduced into the image during image acquisition prior to lens distortion correction. Potential applications of this technology include camera identification using sensor fingerprint, narrowing down the camera model, estimating the distance between the photographer and the subject, forgery detection, and improving the reliability of image steganalysis (detection of hidden data).
Determination of material properties using nanoindentation and multiple indenter tips

Abstract Nanoindentation is a useful method to probe the material properties of a solid. Its effective use lies in interpreting the data collected from a nanoindentation experiment with an associated analytical/numerical solution of the corresponding problem configuration. In this paper, a parametric finite element study has been performed to develop a new procedure for extracting elastic–plastic properties of a material through nanoindentation experiments with a substantially improved accuracy for the elastic properties of a elastic–plastic solid. The procedure involves data collected through the use of two, different, nanoindenter tips. Non-dimensional functions were constructed for two different indenter geometries to show that test results from multiple indenters, when appropriately manipulated, deliver superior results, compared to using one indenter. The material was assumed to be an isotropic elastic–plastic solid with power law hardening. Friction between the indenter and the material was included in the cases studied. The ratio of yield strength to elastic modulus was assumed to be in the range 0.0005–0.02 and the hardening coefficient was assumed to be between 0 and 0.4. Poisson’s ratio was fixed at 0.3.
Polarization Imaging in Shadow and Glare

In shadow and glare regions traditional imaging methods may yield inaccurate polarization information due to dynamic range limit, noise, and black-level fluctuation. This new method solves these issues and yields accurate polarization information.
Stability of DMDHEU and Alkylated Crosslinking Finishes Towards Acidic and Alkaline Hydrolysis

Cotton fabrics treated with various alkylated derivatives of DMDHEU were subjected to hydrolysis by urea-phosphoric acid, hot 23% sodium hydroxide, and urea-phosphoric acid followed by sodium hydroxide. Sequential treatment with acid and base removed more nitrogen and formaldehyde than the alkaline treatment, which removed more nitrogen and formaldehyde than the acid treatment. Stability of the crosslinks generated by these resins depended on both the degree of alkylation of DMDHEU and the nature of the alkyl cap. This stability was reflected in greater amounts of residual nitrogen and formaldehyde after hydrolysis. Those residues, in turn, affected the residual break ing strength, flex abrasion resistance, and wrinkle recovery of the hydrolyzed fabrics. The stability of the crosslinks also correlated well with formaldehyde release data for the treated fabrics.
Adding maps (GPS) to accelerometry data to improve study participants’ recall of physical activity: a methodological advance in physical activity research

Objective Obtaining the ‘when, where and why’ of healthy bouts of moderate-to-vigorous physical activity (MVPA) provides insights into natural PA. Design In Salt Lake City, Utah, adults wore accelerometer and Global Positioning System (GPS) loggers for a week in a cross-sectional study to establish baseline travel and activity patterns near a planned Complete Street intervention involving a new rail line, new sidewalks and a bike path. Results At the end of the week, research assistants met with the 918 participants who had at least three 10 h days of good accelerometer readings. Accelerometer and GPS data were uploaded and integrated within a custom application, and participants were provided with maps and time information for past MVPA bouts of ≥3 min to help them recall bout details. Participants said that ‘getting someplace’ was, on average, a more important motivation for their bouts than leisure or exercise. A series of recall tests showed that participants recalled most bouts they were asked about, regardless of the duration of the bout, suggesting that participant perceptions of their shorter lifestyle bouts can be studied with this methodology. Visual prompting with a map depicting where each bout took place yielded more accurate recall than prompting with time cues alone. Conclusions These techniques provide a novel way to understand participant memories of the context and subjective assessments associated with healthy bouts of PA. Prompts with time-stamped maps that illustrate places of MVPA offer an effective method to improve understanding of activity and its supportive sociophysical contexts.
Antibody-Dependent Enhancement, a Possible Mechanism in Augmented Pulmonary Disease of Respiratory Syncytial Virus in the Bonnet Monkey Model

Bonnet monkeys develop an enhanced disease after immunization with the formalin-inactivated (FI) respiratory syncytial virus (RSV) vaccine that is characterized by increased viral replication in perivascular sites of the lung. These sites contain many mononuclear cells, which are known to be permissive for RSV replication. To test the hypothesis that FI-RSV vaccine stimulates the production of enhancing antibodies that serve to increase the replication of RSV in macrophages, in vitro studies were done. Antibody-dependent enhancement was observed in animals immunized with FI-RSV but not in control animals with primary and tertiary infections or those immunized with FI-Vero cell culture. In the presence of serum samples from animals immunized with FI-RSV, an increased number of U937 cells was infected. The enhancement index correlated positively with the pathologic scores of the FI-RSV-vaccinated monkeys.
A Review of Methods for Missing Data

This paper reviews methods for handling missing data in a research study. Many researchers use ad hoc methods such as complete case analysis, available case analysis (pairwise deletion), or single-value imputation. Though these methods are easily implemented, they require assumptions about the data that rarely hold in practice. Model-based methods such as maximum likelihood using the EM algorithm and multiple imputation hold more promise for dealing with difficulties caused by missing data. While model-based methods require specialized computer programs and assumptions about the nature of the missing data, these methods are appropriate for a wider range of situations than the more commonly used ad hoc methods. The paper provides an illustration of the methods using data from an intervention study designed to increase students’ ability to control their asthma symptoms.
The role of Bacterial-based Protist Communities in Aquatic and Soil Ecosystems and the Carbon Biogeochemical Cycle, with Emphasis on Naked Amoebae

Current research is reviewed on aquatic and soil microbial ecology with attention to the fate of organic carbon in bacterial-based protist food webs, including some new data. Particular attention is given to the effects of pulsed sources of low-molecular weight organic sources of carbon on soil respiration, changes in bacterial, nanoflagellate, and naked amoeba C-biomass, and evidence for throughput of carbon in microbial food webs in Arctic and some low-latitude, temperate soil environments. The proportion of pulsed sources of glucose-C that is sequestered in microbial biomass relative to loss as CO 2 is examined in laboratory experimental studies, and implications of the re- search for microbial community dynamics and global warming due to terrestrial sources of respiratory CO 2 are discussed.
Looking Beyond Fibrillar Features to Scale Gecko-Like Adhesion

Hand-sized gecko-inspired adhesives with reversible force capacities as high as 2950 N (29.5 N cm(-2) ) are designed without the use of fibrillar features through a simple scaling theory. The scaling theory describes both natural and synthetic gecko-inspired adhesives, over 14 orders of magnitude in adhesive force capacity, from nanoscopic to macroscopic length scales.
Diffuse optical tomography with physiological and spatial a priori constraints

Diffuse optical tomography is a typical inverse problem plagued by ill-condition. To overcome this drawback, regularization or constraining techniques are incorporated in the inverse formulation. In this work, we investigate the enhancement in recovering functional parameters by using physiological and spatial a priori constraints. More accurate recovery of the two main functional parameters that are the blood volume and the relative saturation is demonstrated through simulations by using our method compared to actual techniques.
Five scientists at Johns Hopkins in the modern evolution of neuroscience.

Neuroscience’s evolution at Johns Hopkins, from neurophysiology to the new field of neurobiology, though unplanned, was rapid and important. Beginning in 1933 when Philip Bard became professor of physiology at Johns Hopkins, members of his department concentrated initially on neuroanatomical control of placing reactions and sexual activity. Vernon Mountcastle, extending available techniques, discovered vertical somato-sensory columns in the 1950's. Stephen Kuffler, who arrived at Hopkins in 1947, was a pioneer in single unit microelectrode recording techniques. He soon attracted scientists from all over the world to his laboratory. Among them, Torsten Wiesel and David Hubel discovered vertical neuronal columns in the visual cortex. During several decades at Johns Hopkins, these five scientists set extremely high scientific standards and established a climate of inquiry in which ideas were shared and young scientists encouraged. They contributed significantly to the emerging discipline of neuroscience.
Stamens are not essential as an attractant for pollinators in females of cryptically dioecious Thalictrum pubescens Pursch. (Ranunculaceae)

It has been hypothesized that females of some dioecious species maintain stamens that produce sterile pollen as a means of attracting pollinators to promote greater seed set. However, this hypothesis has rarely been tested. This paper examines the role of pollinators in the maintenance of sterile stamens in the cryptically dioecious species, Thalictrum pubescens. Wind was found to contribute to pollination; branches of female T. pubescens enclosed in cheesecloth to exclude insects but not wind were still able to set seed. Therefore, females may not need the stamens for pollination. In 1994, insects were found to discriminate against emasculated female flowers, but this discrimination did not lead to a significant difference in either the amount of pollen received or seed set. In 1995, emasculation was combined with the addition of pollen to determine if emasculated females were pollen limited. No significant effect of pollen addition or emasculation was found. Emasculated branches in the pollen-addition treatment appeared to have slightly lower seed set than non-emasculated branches that received pollen, indicating that the slight reduction in seed set was caused by emasculation rather than pollen limitation. Since stamens do not appear to be maintained as pollinator attractants, other explanations, such as genetic constraints, must be investigated.
Divergence in mycorrhizal specialization within Hexalectris spicata (Orchidaceae), a nonphotosynthetic desert orchid.

Evidence is accumulating for specialized yet evolutionarily dynamic associations between orchids and their mycorrhizal fungi. However, the frequency of tight mycorrhizal specificity and the phylogenetic scale of changes in specificity within the Orchidaceae are presently unknown. We used microscopic observations and PCR-based methods to address these questions in three taxa of nonphotosynthetic orchids within the Hexalectris spicata complex. Fungal ITS RFLP analysis and sequences of the ITS and nuclear LSU ribosomal gene fragments allowed us to identify the fungi colonizing 25 individuals and 50 roots. Thanatephorus ochraceus(Ceratobasidiaceae) was an occasional colonizer of mycorrhizal roots and nonmycorrhizal rhizomes. Members of the Sebacinaceae were the primary mycorrhizal fungi in every Hexalectris root and were phylogenetically intermixed with ectomycorrhizal taxa. These associates fell into six ITS RFLP types labeled B through G. Types B, C, D, and G were found in samples of H. spicata var. spicata, while only type E was found in H. spicata var. arizonica and only type F was found in H. revoluta. These results provide preliminary evidence for divergence in mycorrhizal specificity between these two closely related orchid taxa. We hypothesize that mycorrhizal interactions have contributed to the evolutionary diversification of the Orchidaceae. Interactions between species, especially intimate symbioses, have played major roles in the adaptive evolution and diversification of life. In plants, interactions with herbivores, pathogens, pollinators, seed dispersers, and mutualistic soil microorganisms have been particularly influential. Mycorrhizal symbioses with soil fungi are ancient, possibly dating to the emergence of plants on land (Heckman et al., 2001) and are still critical to the mineral nutrition of most wild plants (Smith and Read, 1997). While mycorrhizal interactions have certainly influenced the evolution of nutrient uptake strategies in plants, most plants do not interact specifically with narrow taxonomic groups of fungi (Molina et al., 1992), making pairwise coevolution between plant and fungal species unlikely (Taylor, 2000). In stark contrast, some members of the species-rich Orchidaceae display marked mycorrhizal specificity toward particular taxonomic groups of basidiomycete fungi (reviewed in Taylor et al., 2002). We use ‘‘specificity’’ to refer to the relative phylogenetic diversity of fungal associates that interact with a particular plant (Thompson, 1994; Taylor and Bruns, 1999b). The mycorrhizal specificity in orchids suggests that mycorrhizal interactions, like pollination syndromes, may have played a role in the diversification of the Orchidaceae. However, we do not know how common mycorrhizal specialization 1
Could you be clearer? An examination of the multiple perspectives of clarity

The author examines three of the most important factors that affect readers' and writers' perceptions of clarity: precision, document accessibility, and corporate language context. Each factor is defined and examined in terms of its influence on clarity. The result is a better understanding of the multiple factors that need to be considered before one passes judgment on a document's clarity. >
Performance Analysis of a Queue with Congestion-Based Staffing Policy

This paper analyzes a waiting line system that is motivated by the operations of border-crossing stations between the United States and Canada. There are two main conflicting goals in such a system: high security level, which often leads to a longer line; and good customer service, which requires a shorter line. Thus, unlike other queueing systems, maintaining the average queue length within a certain range is the primary objective. This is achieved using a staffing policy, called “congestion-based staffing,” or CBS, where the number of servers (inspection booths) is adjusted according to the queue length during a planning period. We first present an exact benchmark model of Markovian type based on the matrix-geometric solution. For practical CBS policies, we develop a set of closed-form formulas for the major performance measures based on regenerative cycle analysis and fluid limit approximation. Numerical examples show that these approximation formulas are simple, accurate, and robust for practitioners to use in designing CBS policies.
Simultaneous Recognition of a Carboxylate-Containing Ligand and an Intramolecular Surrogate Ligand in the Crystal Structure of an Asymmetric Vancomycin Dimer

Vancomycin is one of the most important and commonly used antibiotics in hospitals. Despite numerous investigations, however, it is not clear how vancomycin recognizes its site of action in the bacterial cell wall. The increasing incidence of bacterial resistance to vancomycin makes it imperative to understand these recognition determinants so that alternative agents may be developed. Herein we report the first crystal structure of vancomycin. The structure resolves a long-standing controversy about carboxylate recognition by vancomycin, suggests a possible cooperative mechanism linking ligand binding and dimerization, and demonstrates the operation of a novel intramolecular flap which occupies the binding site in the absence of ligand.
Revisiting Economic Sanctions Reconsidered

Hufbauer, Schott and Elliott have written probably the most comprehensive empirical study of economic sanctions in their volume Economic Sanctions Reconsidered: History and Current Policy. They conclude their analysis with several policy recommendations. However, there are problems with their empirical analysis that significantly affect these recommendations. To overcome these problems, I reanalyze their data using ordered logit estimation. In addition to modeling their policy recommendations, I add three hypotheses derived from the sanction literature. The results show that most of the relationships between the variables in their recommendations are insignificant, calling their accuracy and importance into question. In two cases, the original recommendations are accurate only when conditioned by other variables. Cooperation only has a negative effect on success when international organizations are not involved, and nations trying to subvert the sanctions only succeed when the target was originally dependent on the sender for its imports. I conclude by discussing the policy implications these findings have for the future use of economic sanctions.
Directing pathfinding along the dorsolateral path - the role of EDNRB2 and EphB2 in overcoming inhibition.

Neural crest cells that become pigment cells migrate along a dorsolateral route between the ectoderm and the somite, whereas most other neural crest cells are inhibited from entering this space. This pathway choice has been attributed to unique, cellautonomous migratory properties acquired by neural crest cells when they become specified as melanoblasts. By shRNA knockdown and overexpression experiments, we investigated the roles of three transmembrane receptors in regulating dorsolateral pathfinding in the chick trunk. We show that Endothelin receptor B2 (EDNRB2) and EphB2 are both determinants in this process, and that, unlike in other species, c-KIT is not. We demonstrate that the overexpression of EDNRB2 can maintain normal dorsolateral migration of melanoblasts in the absence of EphB2, and vice versa, suggesting that changes in receptor expression levels regulate the invasion of this pathway. Furthermore, by heterotopic grafting, we show that neural crest cell populations that do not rely on the activation of these receptors can migrate dorsolaterally only if this path is free of inhibitory molecules. We conclude that the requirement for EDNRB2 and EphB2 expression by melanoblasts is to support their migration by helping them to overcome repulsive or non-permissive cues in the dorsolateral environment.
Large Dimensional Factor Analysis

Econometric analysis of large dimensional factor models has been a heavily researched topic in recent years. This review surveys the main theoretical results that relate to static factor models or dynamic factor models that can be cast in a static framework. Among the topics covered are how to determine the number of factors, how to conduct inference when estimated factors are used in regressions, how to assess the adequacy of observed variables as proxies for latent factors, how to exploit the estimated factors to test unit root tests and common trends, and how to estimate panel cointegration models. The fundamental result that justifies these analyses is that the method of asymptotic principal components consistently estimates the true factor space. We use simulations to better understand the conditions that can affect the precision of the factor estimates.
FUNDAMENTAL STUDY, AND EQUIPMENT FOR SINTERING AND TESTING OF CERMET BODIES: IV, DEVELOPING AND TESTING EQUIPMENT*

A relatively large molybdenum-wound resistor furnace, a diamond-wheel rod-grinding machine, a tensile stress-rupture machine, and thermal-expansion equipment used for the development and testing of cermets are described. All are additions to equipment described previously, having been designed and used successfully during the past year.
ADR Accounting Principles Choice And The Market Reaction To Form 20-F

In this study, we conjecture that non-U.S. firms, choosing to be listed on the major U.S. exchanges, will incur the added costs associated with the supplemental disclosure requirements in order to get that information impounded in the home country equity share price via the ADR share price in the manner described by Fishman and Hagerty (1989). More specifically, we evaluate the equity share response to U.S.-listed ADR Form 20-F filing in a manner similar to Chen and Sami (2009, 2008) anticipating that the incremental disclosures will prompt ADR and equity security share responses. Unlike prior studies, we investigate whether the Form 20-F filings prompt U.S. dominant cross-market information flows from the ADR share market back to the home country equity share market proportional to the incremental Form 20-F information. We employ bivariate and single equation models of the cross-market ADR and equity security share response to the filing, controlling for the firm-specific Form 20-F accounting principles choice. Preliminary results indicate that both ADR and equity security share markets respond to the Form 20-F filing. There is a strong indication that the U.S. ADR share market response dominates the cross-market information flow driving the home country equity share market response. Furthermore, we find that the cross-market response to ADR Form 20-F filing is not equal across the three available accounting principle choices in either the ADR share market or the home country equity share market. Our results are consistent with U.S. GAAP conveying the most of new price relevant information, IFRS, and local accounting standards being informative but not to the same extent.
Non-paraganglioma jugular foramen lesions masquerading as glomus jugulare tumors

Pulsatile tinnitus, hearing loss, lower cranial nerve deficits, and radiographic evidence of a vascular lesion of the jugular foramen have been considered diagnostic of a glomus jugulare tumor. Angiographic evidence of a blood supply from the external carotid artery system, including the ascending pharyngeal artery, further substantiates this diagnosis. This diagnostic algorithm for tumors of the jugular fossa is usually followed by either a surgical exenteration of a presumed glomus jugulare tumor via an infratemporal fossa approach or radiation therapy in selected patients. Pre-treatment biopsy of such lesions is typically not done, nor is it recommended widely in the literature. As demonstrated in this report, a number of lesions, including hemangiopericytoma and extramedullary plasmacytoma presenting in the jugular foramen can mimic glomus jugulare tumors in all aspects of their clinical and radiographic presentation. Omission of a pre-treatment biopsy can lead to a treatment plan appropriate for glomus tumors but suboptimal for these rare pathologic entities. A pre-treatment biopsy of lesions of the jugular foramen by exploratory tympanotomy or postauricular mastoidotomy provides a pathologic diagnosis on which to base treatment of lesions of the jugular foramen, without adding substantial morbidity or decreasing the chances of cure.
Some effects of water potential upon endophytic Acremonium spp. in culture

Acremonium coenophialum, A. starrii, and A. typhinum were grown on potato dextrose agar (PDA) amended with KC1 (PDA + KC1) or sucrose (PDA + S) to attain a wide range of osmotic water potentials. Radial growth was greatest between -0.3 MPa (PDA without amendment) and -3.0 to -4.0 MPa, below which growth diminished to near zero at -8 MPa. Acremonium isolates grew well on corn
Morphometric Variability in Natural and Laboratory Populations of CulicolDes Variipennis (Diptera: Ceratopogonidae)

Natural populations of Culicoides variipennis (Coq.) vary greatly from one habitat to another even when these habitats are in close proximity. This distinctness of populations was noted when morphological variables were considered singly or when multivariate statistical techniques were employed. Similarly, pronounced temporal variation was revealed in each of 2 populations observed at different times. Subsamples of larvae from an inbred laboratory population reared at different temperatures showed differences for every variable examined. Regression analysis revealed a definite relationship between temperature and nearly every morphological variable examined. These results suggest that the present subspecific nomenclature for the C. variipennis complex is perhaps invalid, and true biological subgroupings can be described only as the result of more refined genetic analyses.
Possible Mechanisms for Thermal Conductivity Enhancement in Nanofluids

This study discusses the merits of various physical mechanisms that are responsible for enhancing the heat transfer in nanofluids. Experimental studies have cemented the claim that ‘seeding’ liquids with nanoparticles can increase the thermal conductivity of the nanofluid by up to 40% for metallic and oxide nanoparticles dispersed in a base liquid. Experiments have also shown that the rise in conductivity of the nanofluid is highly dependent on the size and concentration of the nanoparticles. On the theoretical side, traditional models like Maxwell or Hamilton-Crosser models cannot explain this unusually high heat transfer. Several mechanisms have been postulated in the literature such as Brownian motion, thermal diffusion in nanoparticles and thermal interaction of nanoparticles with the surrounding fluid, the formation of an ordered liquid layer on the surface of the nanoparticle and microconvection. This study concentrates on 3 possible mechanisms: Brownian dynamics, microconvection and lattice vibration of nanoparticles in the fluid. By considering two nanofluids, copper particles dispersed in ethylene glycol, and silica in water, it is determined that translational Brownian motion of the nanoparticles, presence of an interparticle potential and the microconvection heat transfer are mechanisms that play only a smaller role in the enhancement of thermal conductivity. On the other hand, the lattice vibrations, determined by molecular dynamics simulations show a great deal of promise in increasing the thermal conductivity by as much as 23%. In a simplistic sense, the lattice vibration can be regarded as a means to simulate the phononic transport from solid to liquid at the interface.Copyright © 2006 by ASME