cssi/SciSciGPT-SciSciNet huggingface dataset:
Empirical molecular-dynamics study of diffusion in liquid semiconductors.

We report the results of an extensive molecular-dynamics study of diffusion in liquid Si and Ge (l-Si and l-Ge) and of impurities in l-Ge, using empirical Stillinger-Weber (SW) potentials with several choices of parameters. We use a numerical algorithm in which the three-body part of the SW potential is decomposed into products of two-body potentials, thereby permitting the study of large systems. One choice of SW parameters agrees very well with the observed l-Ge structure factors. The diffusion coefficients D(T) at melting are found to be approximately 6.4\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$ ${\mathrm{cm}}^{2}$/s for l-Si, in good agreement with previous calculations, and about 4.2\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$ and 4.6\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}5}$ ${\mathrm{cm}}^{2}$/s for two models of l-Ge. In all cases, D(T) can be fitted to an activated temperature dependence, with activation energies ${\mathit{E}}_{\mathit{d}}$ of about 0.42 eV for l-Si, and 0.32 or 0.26 eV for two models of l-Ge, as calculated from either the Einstein relation or from a Green-Kubo-type integration of the velocity autocorrelation function. D(T) for Si impurities in l-Ge is found to be very similar to the self-diffusion coefficient of l-Ge. We briefly discuss possible reasons why the SW potentials give D(T)'s substantially lower than ab initio predictions. \textcopyright{} 1996 The American Physical Society.
The Influence of Culture Time and Passage Number on the Morphological and Physiological Development of Caco-2 Cells

The Caco-2 cell line is used by many investigators as a model of the intestinal epithelium to study nutrient uptake and transport. Our goal was to create an awareness of inherent variabilities in the Caco-2 cell line which may influence their suitability as a model or their application to specific problems. To study the influence of passage on the model, cultures were monitored from passage 20 to 109. Transepithelial electrical resistance (TEER) and sucrase activity (measured in 21-day-old cultures) increased through about passage 36. TEER values declined after about passage 60; sucrase remained elevated but variable. Cells at passage 22, 33, and 72 were grown simultaneously for 24 days. Older-passaged cells reached plateau phase sooner. Before Day 15, passage 72 cells had higher TEER and lower permeability to 14C-mannitol than passages 22 and 33; however, after Day 15 all passages showed similar permeability. On Day 21, passage 72 cells had significantly lower alkaline phosphatase activity than did the other passages. Electron microscopy did not reveal any major morphological differences between the passages; however, it did show that some areas of cells grown on membranes were not monolayers but were several cells thick with varied morphology. Investigation of the formation of these multilayered areas showed them to be an inherent part of cell growth under the conditions used. These results emphasize the inherent variability in Caco-2 cell models and emphasize the need to monitor closely the culture characteristics during growth and differentiation under specific experimental conditions.
Genetics of pediatric interstitial lung disease.

Purpose of review The interstitial lung diseases are a heterogeneous group of rare disorders of largely unknown etiology. The occurrence of familial cases of pediatric interstitial lung diseases with the onset of symptoms developing early in infancy has suggested a genetic basis for some forms of interstitial lung diseases in children. Recent findings Mutations in the genes encoding surfactant protein C, SFTPC, and a member of the adenosine triphosphate-binding cassette family of proteins, ABCA3, have been shown to result in pediatric interstitial lung diseases inherited in autosomal-dominant and autosomal-recessive patterns, respectively. There is overlap in both the clinical and histopathologic features of these disorders. Summary Identification of genes responsible for pediatric interstitial lung diseases provides the opportunity for noninvasive testing to establish an etiologic diagnosis, to counsel family members for their recurrence risk, and to classify these rare disorders more accurately. A better understanding of the cause and pathophysiology of these disorders may provide additional insights into the causes of other forms of pediatric interstitial lung diseases, and may suggest novel treatment approaches.
Ciprofloxacin attachment to porous-coated titanium surfaces

A simple and effective method for attaching ciprofloxacin HCl salt to the surface of porouscoated titanium based orthopedic materials was developed. The method utilizes the electrophoretic migration of both fine ciprofloxacin HCl particles and ciprofloxacin ions to deposit the antibiotic salt on a positively biased surface. The quantity of antibiotic deposited can be easily and effectively controlled by varying the time of deposition and applied voltage. In vitro tests have indicated that the antimicrobial activity of the treated surfaces is retained for a period of 5 days. The method allows a significant amount of antibiotic to be deposited and could theoretically be used to deliver antibiotics to the tissues surrounding prosthetic devices in order to prevent postoperative infections. © 1994 John Wiley & Sons, Inc.
Putting the dollar signs on quality: the cost of experienced problems in the hotel industry.

This work presents a calculation for the cost of problems experienced in the hotel industry. The calculation is then applied both to the cost of problems experienced and the cost of problems not reported. The calculation presents data at the brand level to illustrate the calculation. By using this formula, hotels, brands, and companies can both identify and monitor the dollar cost of problems experienced to help in their cost/benefit analysis of service improvement efforts.
The influence of organizational justice on accountant whistleblowing

Abstract In this research study, we apply the theory of organizational justice to the design of whistleblowing policies and procedures. As a pro-social behavior, we posit that employee whistleblowing is likely to increase when organizational whistleblowing procedures, outcomes, and related exchanges with superiors are perceived as fair. We test our hypotheses with an experiment involving 447 internal auditors and management accountants. Our results indicate that whistleblowing policies and mechanisms incorporating higher levels of procedural justice, distributive justice, and interactional justice were perceived to increase the likelihood that an organizational accountant would internally report financial statement fraud.
An outbreak of Asian influenza in tuberculous patients.

An outbreak of Asian influenza which occurred in a tuberculosis sanatorium was limited to a single ward. All of the 31 girls confined to this ward contracted the infection as judged by an increase in titers of both HI and CF antibody against Asian influenza virus. However, in spite of a rise in antibody titer, two of the girls showed no clinical symptoms. The immune response of these tuberculous patients was similar to the immune response seen in non-tuberculous individuals. Also, the HI antibody response to Asian influenza vaccine was comparable to that of normal populations given a similar dosage of vaccine. Except in two individuals, the viral infection did not appear to affect adversely the tuberculous disease present in these patients. In one of the two cases, the adverse effect was reversed within a period of two months and the patient's tuberculosis has since continued to improve. The tuberculosis of the other patient has continued to worsen since the onset of the viral infection.
Do not forget about HELLP

A 32-year-old female para 4 gravi 3, who was 21 weeks pregnant, presented to the emergency department (ED) with a 2-day history of abdominal pain, headache, blurred vision and vomiting. On arrival, she was agitated and confused with a blood pressure 162/106 mm Hg, pulse rate 107, respiratory rate 18, temperature 37 degrees Celsius, point of care blood glucose 6.2 and her Glasgow coma scale was 13/15 M6V4E3. Paramedics witnessed seizure-like activity lasting <1 min during transport. A diagnosis of eclampsia complicated by the HELLP syndrome (haemolysis, elevated liver enzymes, low platelets count) was made. She was commenced on magnesium and labetalol intravenously for blood pressure control. Initial blood test results were consistent with the HELLP syndrome. Recognition of the HELLP syndrome with prompt management of blood pressure and clotting abnormalities is essential in the ED setting. An aggressive multidisciplinary approach is a key to optimise the prognosis for mother and fetus.
Interactive effects of pH, arsenic and phosphorus on uptake of As and P and growth of the arsenic hyperaccumulator Pteris vittata L. under hydroponic conditions

Abstract Arsenic (As)-contaminated soil and water vary with pH and concentrations of As and P. This study examined the effects and interactions of three factors, pH, As and P, on As hyperaccumulator Pteris vittata L. to optimize plant growth and maximize As removal from contaminated sites, especially water. Two sets of hydroponic experiments were conducted using three-factor, five-level central composite design. Five levels of pH (4.5–8.0), As (0–668 μM), and P (0–1000 μM) were used to understand their individual as well as interactive effects. Plant biomass and uptake of P and As were impacted by all the three factors. Phosphorus inhibited As uptake at all concentrations, whereas As below 334 μM benefited plant growth and P uptake. Enhanced plant biomass was most likely a result of increased P uptake. Low pH enhanced plant uptake of As (pH≤5.21) and P (pH≤6.25). The fern had a relatively high biomass and P uptake at low pH/low As or high pH/high As. The referencing saddle points (turning points) were pH 6.33 and As 359 μM for plant biomass and pH 5.87 and As 331 μM for P uptake based on the response surface plot. The results suggested that optimum plant growth could be achieved by adjusting pH corresponding to As levels in the growth media, and maximum plant As hyperaccumulation by maintaining minimum P concentrations with medium pH≤5.21. Our results should be useful for developing strategies to remediate As-contaminated water using Chinese Brake fern.
Myocardial oxidative stress, osteogenic phenotype, and energy metabolism are differentially involved in the initiation and early progression of δ-sarcoglycan-null cardiomyopathy

Dilated cardiomyopathy (DCM) is a common cause of heart failure, and identification of early pathogenic events occurring prior to the onset of cardiac dysfunction is of mechanistic, diagnostic, and therapeutic importance. The work characterized early biochemical pathogenesis in TO2 strain hamsters lacking δ-sarcoglycan. Although the TO2 hamster heart exhibits normal function at 1 month of age (presymptomatic stage), elevated levels of myeloperoxidase, monocyte chemotactic protein-1, malondialdehyde, osteopontin, and alkaline phosphatase were evident, indicating the presence of inflammation, oxidative stress, and osteogenic phenotype. These changes were localized primarily to the myocardium. Derangement in energy metabolism was identified at the symptomatic stage (4 month), and is marked by attenuated activity and expression of pyruvate dehydrogenase E1 subunit, which catalyzes the rate-limiting step in aerobic glucose metabolism. Thus, this study illustrates differential involvement of oxidative stress, osteogenic phenotype, and glucose metabolism in the initiation and early progression of δ-sarcoglycan-null DCM.
Numerical Computations of Hypersonic Boundary-Layer over Surface Irregularities

Surface irregularities such as protuberances inside a hypersonic boundary layer may lead to premature transition on the vehicle surface. Early transition in turn causes large localized surface heating that could damage the thermal protection system. Experimental measurements as well as numerical computations aimed at building a knowledge base for transition Reynolds numbers with respect to different protuberance sizes and locations have been actively pursued in recent years. This paper computationally investigates the unsteady wake development behind large isolated cylindrical roughness elements and the scaled wind-tunnel model of the trip used in a recent flight measurement during the reentry of space shuttle Discovery. An unstructured mesh, compressible flow solver based on the space-time conservation element, solution element (CESE) method is used to perform time-accurate Navier-Stokes calculations for the flow past a roughness element under several wind-tunnel conditions. For a cylindrical roughness element with a height to the boundary-layer thickness ratio from 0.8 to 2.5, the wake flow is characterized by a mushroom-shaped centerline streak and horse-shoe vortices. While time-accurate solutions converged to a steady-state for a ratio of 0.8, strong flow unsteadiness is present for a ratio of 1.3 and 2.5. Instability waves marked by distinct disturbance frequencies were found in the latter two cases. Both the centerline streak and the horse-shoe vortices become unstable downstream. The oscillatory vortices eventually reach an early breakdown stage for the largest roughness element. Spectral analyses in conjunction with the computed root mean square variations suggest that the source of the unsteadiness and instability waves in the wake region may be traced back to possible absolute instability in the front-side separation region.
Engineering and characterization of functional human microvessels in immunodeficient mice

Current model systems used to investigate angiogenesis in vivo rely on the interpretation of results obtained with nonhuman endothelial cells. Recent advances in tissue engineering and molecular biology suggest the possibility of engineering human microvessels in vivo. Here we show that human dermal microvascular endothelial cells (HDMEC) transplanted into severe combined immunodeficient (SCID) mice on biodegradable polymer matrices differentiate into functional human microvessels that anastomose with the mouse vasculature. HDMEC were stably transduced with Flag epitope or alkaline phosphatase to confirm the human origin of the microvessels. Endothelial cells appeared dispersed throughout the sponge 1 day after transplantation, became organized into empty tubular structures by Day 5, and differentiated into functional microvessels within 7 to 10 days. Human microvessels in SCID mice expressed the physiological markers of angiogenesis: CD31, CD34, vascular cellular adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1). Human endothelial cells became invested by perivascular smooth muscle α-actin–expressing mouse cells 21 days after implantation. This model was used previously to demonstrate that overexpression of the antiapoptotic protein Bcl-2 in HDMEC enhances neovascularization, and that apoptotic disruption of tumor microvessels is associated with apoptosis of surrounding tumor cells. The proposed SCID mouse model of human angiogenesis is ideally suited for the study of the physiology of microvessel development, pathologic neovascular responses such as tumor angiogenesis, and for the development and investigation of strategies designed to enhance the neovascularization of engineered human tissues and organs.
The Solar Wind Interaction with Comet p/ Grigg / Skjellerup

The Giotto spacecraft is scheduled to intercept comet P/Grigg-Skjellerup on July 10, 1992. The observed outgassing rate of this comet is over an order of magnitude smaller than comet Giacobini-Zinner and over two orders of magnitude smaller than that of comet Halley. Consequently, the new data obtained during the upcoming encounter will strengthen our understanding of how the solar wind interaction with comets depends upon the neutral gas production rate. In this brief note, we make predictions of the location of the flow transition regions — i.e., the bow shock and the ionopause, and discuss the expected level of wave turbulence.
Experimental studies of electroosmotic flow dynamics in microfabricated devices during current monitoring experiments.

Electroosmotic flow (EOF) was monitored in glass microfluidic devices at rates up to 2 Hz with a precision of 0.2−1.0% using a technique based on the periodic photobleaching of a dilute, neutral fluorophore added to the running buffer. This EOF monitoring method was used to examine the performance of the current monitoring technique for measuring an average electroosmotic flow in a microfluidic device with a cross-T design. Flow measurements made with the current monitoring method gave a precision of 0.4−2.2%, but the periodic photobleaching method shows that the current monitoring technique causes changes in EOF as high as 41% during a single experiment. The periodic photobleaching method for EOF monitoring was also used to study EOF in channels on opposite sides of a cross-channel intersection. The opposite channels were shown to exhibit substantially different EOF dynamics during a current monitoring experiment as well as different steady-state EOF rates during normal operating conditions.
Who Are the Price Vigilantes? An Investigation of Differentiating Characteristics Influencing Price Information Processing

Abstract Research suggests that many consumers exhibit poor price recall, even at the point-of-purchase and that some consumers are more price vigilant than others. We incorporate Stigler's economics of information concept into a multinomial logit model to explore differentiating factors that influence the price recall information at the point-of-purchase. Intercepting subjects at the point-of-purchase in an actual retail setting, data were collected from 289 subjects across four product categories and three stores. We find that price recall is influenced by correctly perceived promotion status of the brand, use of the price in making the purchase decision, and income. Two other demographic variables, gender and age, had no impact on price recall. We discuss implications for researchers, retail managers, and consumer advocacy groups.
Video-QoE aware resource management at network core

We address the problem of video-aware multiuser resource management in modern wireless networks such as 3GPP Long Term Evolution (LTE) in the context of video delivery systems like HTTP Adaptive Streaming (HAS). HAS is a client driven video rate adaptation and delivery framework that is becoming popular due to its inherent advantages over existing video delivery solutions. Quality of Experience (QoE) is the prime performance criterion for adaptive video streaming and wireless resource management is a critical part in providing a target QoE for video delivery over wireless systems. However modifying resource management functionality to be video-aware at the network edge is rather difficult in practical networks. In this paper, we propose an alternative architecture to enhance video QoE in QoS (Quality of Service)-aware networks wherein the intelligence for video aware resource management resides at the network-core rather than at the network edge. In this new architecture, a "Video Aware Controller" (VAC) is placed at the network core. The VAC periodically receives HAS-related feedback from adaptive streaming clients/servers which it converts to QoS parameters for each user. Further, we propose an algorithm to dynamically compute the Maximum Bit Rate (MBR) for each streaming user based on media buffer feedback. Our simulation results on an LTE system level simulator demonstrate significant reduction in re-buffering percentage and enhanced QoE-outage capacity compared to existing schemes.
Synthesis and Characterization of PS-PIB-PS Triblock Copolymers

Abstract Poly(styrene-isobutylene-styrene) (PS-PIB-PS) block copolymers synthesized via living carbocationic polymerization using a di- or tricumyl chloride/TiCl4/pyridine initiating system in 60/40 (v/v) hexane/methyl chloride cosolvents. The kinetics of formation of the PIB block at − 80°C were found to be first order in isobutylene (IB) concentration, first order in the concentration of initiating sites, second order in TaiCl4 concentration, and a negative fractional order with respect to the pyridine concentration. The rate of polymerization was found to decrease with increasing temperature, indicating an equilibrium between dormant, covalent and active, ionized chain ends, and chain-end concentration studies suggested that there was no contribution by free ions to the rate of propagation. Diagnosis of the livingness of the IB polymerization indicated that at high (≥90%) monomer conversion, β-proton elimination becomes important, causing the timing of addition of styrene to be critical. Addition of st...
Impacts of long‐term changes in fishery management on the trophic level water quality in Czech fish ponds

The management of Czech fish ponds changed little from the Middle Ages until the end of the nineteenth century. The intensification of fish production was initiated during the first half of the twentieth century. During the 1930s, liming and manuring of the ponds became common. A greater density of stocking led to the use of artificial feeds in the form of pellets and grain. These changes in pond management have led to an increase in fish production from ≈ 50 to > 500 kg ha−1 year−1 over the last 5 decades. At the same time, the quality of the water and sediments has been deteriorating, and the functioning of the pond ecosystem has been disturbed. There are now massive blooms of phytoplankton, especially cyanobacteria, accompanied by great fluctuations in the oxygen concentration and pH. Data collected since 1925, when systematic research on the ponds started, allow the mechanisms responsible for the changes to be traced.
A simple linear heuristic for the service constrained random yield problem

We consider the problem of setting order quantities for purchased components subject to uncertainty in the delivery amounts. Assuming the periodic production volumes (demands) to be known and constant, we model this as a random yield problem with the objective of minimizing average inventory cost subject to a service level constraint over the infinite horizon. We first demonstrate that under conditions of random yield, conventional definitions of service can be inappropriate. Then we refine the definition of service for random yield cases and use this to formulate an optimization model. Exact solution of this model proves to be computationally impractical and, as we show, the common heuristic of inflating demands by a constant proportion is not robustly accurate. Therefore, we develop a new heuristic, which we term the linear inflation policy, that specifies a linear function for the inflation factors. Numerical tests indicate that this heuristic can substantially outperform the traditional constant inflation policy and works well relative to a lower bound on the optimal solution on a range of examples.
The hemoglobin of the aquatic snail, Planorbella duryi (Wetherby)

Abstract 1. 1. The hemoglobin of the pond snail, Planorbella duryi has a molecular weight of 1.64 × 10 6 to 1.77 × 10 6 as determined by light-scattering at 630 nm and a sedimentation coefficient of 36 S. 2. 2. The analysis of the circular dichroism spectrum obtained in the 190–250 nm region suggests a high degree of helical folding of the polypeptide chains of P. duryi hemoglobin analogous to human hemoglobin and myoglobin, with estimates of α-helical folding of about 60–65%, 0–5% β-structure, and the remaining portion of the chains in unordered form. 3. 3. The dissociated subunits in 6.0 M GdmCl, in the absence and in the presence of reducing reagent (0.1 M dithiothreitol), have a molecular weight of 3.73 ± 0.23 × 10 5 and 1.93 ± 0.04 × 10 5 , suggesting a di-decameric assembly of the parent hemoglobin organized in the form of five dimers held together by disulfide-linkages 4. 4. The native hemoglobin is strongly resistant to both pH dissociation and dissociation by urea and such salts as NaCl and NaClO 4 . Dissociation and denaturation could only be effected in concentrated GdmCl solutions. 5. 5. The influence of the various dissociating agents on the quarternary structure suggest ionic stabilization of the decameric assembly, which is stabilized by salt bridges between the subunits.
Living Telenovelas/Telenovelizing Life: Mexican American Girls' Identities and Transnational Telenovelas

This article examines the local reception of global Spanish-language soap operas, or telenovelas. Developed from a 2-year ethnography of Mexican American media consumption in San Antonio, Texas, this article explores how young people talked about Mexican telenovelas in daily life. The researcher selected one telenovela to analyze as it was watched from its beginning to end. From the data, the researcher concluded that the telenovela, within certain limits, reflected some of the national, ethnic, gender, and class tensions that defined the viewers' identities as working-class, Mexican American girls.
Provincial Readers and Agrarian Reform, 1760s–70s: The Case of Sloboda Ukraine

Since the founding of the Free Economic Society, no small effort and labor have been spent on publishing useful advice and instructions, but the desired effect is nowhere to be found. In this locale I have observed that only recently have they begun to learn to use potatoes. They spin and weave cotton (for which a factory in Kazan has already been built) and stockings and caps are knit from it. Many homes here already use goat hair. And this year Siberian buckwheat, which previously succumbed to frost and which before was unknown, has begun to be sown in some places. Undoubtedly, from time to time other instructions of the Society may be put to use; but immediately and quickly, and without the support of the supreme power, they will never become general custom.
Short‐term change in dental providers' diagnostic data recording behavior following an educational intervention

The short-term results of a quasi-experimental controlled trial of an educational intervention designed to improve dentists' and hygienists' diagnostic record-keeping behavior are described. Providers in 21 experimental practices received individualized performance feedback, participated in tutorial, problem-solving, and goal-setting sessions, and were offered technical assistance. The proportions of patient records containing notations for periodontal examination findings were determined through pre- and postintervention record audits in these offices and 15 control offices. Baseline notation rates, which were uniformly low, were not different between groups. Mean notation rates increased between five- and fifteenfold among experimental practices, and less than twofold among controls. The differences in amount of change were significant for two of the three indicator conditions when all patient records were included in the analyses and for all three conditions among a subset of patient records where the patient was known to exhibit the condition. This moderately intensive CDE effort resulted in substantial improvement in provider behavior, but postintervention notation rates, approximately 30%, represented incomplete adoption of recommended behaviors. The level of adoption suggests that more intensive CDE would be necessary for most providers to achieve reasonable performance standards.
Enhancement of dispersion modulation in nanoscale waveguides

We analyze the behavior of group and phase velocities in optical waveguides supporting strongly confined propagating modes. We discuss the implications of material absorption for electromagnetic properties of nanoguides and develop an analytical description of the interplay between geometry-induced and materials-induced dispersions. In the limit of strong confinement, the phase velocity of waveguide modes becomes vanishingly small, while group velocity can be modulated from negative to positive values. The modulation of group velocity is enhanced by the factor of λ2/R2 with respect to macroscopic systems. Both slow- and fast-light regimes can be achieved in the same nanoguiding structure, and dynamical switching between the two regimes is possible. Applications of the developed formalism lie in the field of ultrafast active nanophotonics.
Fine structure and development of Pilosporella chapmani (Microspora: Thelohaniidae) in the mosquito, Aedes triseriatus (Say).

. New information on the life cycle and fine structure of Pilosporella chapmani, a microsporidium of the mosquito Aedes triseriatus, is presented. Pilosporella chapmani is shown to have two sporulation sequences, one of them being involved in transovarial transmission. One sequence, involving meiosis and production of a moniliform sporogonial plasmodium, occurs in the larval fat body, resulting in eight uninucleate, spherical, and fully developed spores. The other occurs in oenocytes of adult mosquitoes and results in isolated, binucleate, elongate, and thin-walled spores. Also, for the first time, metabolic products are shown to be expelled into the surrounding host tissues through the wall of the sporocyst.
Cannabis and the U.S. Controlled Substances Act

Abstract The scheduling of cannabis under the Controlled Substances Act (CSA) has established legal precedents that determine how scientific evidence affects its regulation in the United States. This background challenges three common fallacies that make it seem marijuana prohibition is the only viable policy outcome. A contemporary effort to reschedule cannabis is based on recent findings that have established that marijuana lacks the high potential for abuse required for Schedule I or Schedule II status under the CSA. The primary policy issue is not, then, whether marijuana is the best medicine but instead whether people who use it medically should be treated as criminals.
Experience, Pedagogy, and the Study of Terrestrial Magnetism

In 1842, British astronomer Sir John Herschel wrote a letter to Carl Friedrich Gauss seeking his advice about how to make data collection more efficient on the Magnetic Crusade, a large-scale initiative to study the earth's magnetic field. Surprisingly, even though Gauss had managed a similar initiative, he refused to give Herschel the advice he wanted, claiming that he needed to see Herschel's results before he could reply. Taking this miscommunication as a point of departure, this article traces the cause of this miscommunication to differences in how each scientist viewed scientific training and the communicability of different kinds of scientific knowledge.
Fluorescence-based Broad Dynamic Range Viscosity Probes

We introduce two new fluorescent viscosity probes, SYBR Green (SG) and PicoGreen (PG), that we have studied over a broad range of viscosity and in collagen solutions. In water, both dyes have low quantum yields and excited state lifetimes, while in viscous solvents or in complex with DNA both parameters dramatically (300–1000-fold) increase. We show that in log-log scale the dependence of the dyes’ quantum yield vs. viscosity is linear, the slope of which is sensitive to temperature. Application of SG and PG, as a fluorescence-based broad dynamic range viscosity probes, to the life sciences is discussed.
Tbx1 is required autonomously for cell survival and fate in the pharyngeal core mesoderm to form the muscles of mastication

Velo-cardio-facial/DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a congenital anomaly disorder characterized by craniofacial anomalies including velo-pharyngeal insufficiency, facial muscle hypotonia and feeding difficulties, in part due to hypoplasia of the branchiomeric muscles. Inactivation of both alleles of mouse Tbx1, encoding a T-box transcription factor, deleted on chromosome 22q11.2, results in reduction or loss of branchiomeric muscles. To identify downstream pathways, we performed gene profiling of microdissected pharyngeal arch one (PA1) from Tbx1+/+ and Tbx1−/− embryos at stages E9.5 (somites 20–25) and E10.5 (somites 30–35). Basic helix–loop–helix (bHLH) transcription factors were reduced, while secondary heart field genes were increased in expression early and were replaced by an increase in expression of cellular stress response genes later, suggesting a change in gene expression patterns or cell populations. Lineage tracing studies using Mesp1Cre and T-Cre drivers showed that core mesoderm cells within PA1 were present at E9.5 but were greatly reduced by E10.5 in Tbx1−/− embryos. Using Tbx1Cre knock-in mice, we found that cells are lost due to apoptosis, consistent with increase in expression of cellular stress response genes at E10.5. To determine whether Tbx1 is required autonomously in the core mesoderm, we used Mesp1Cre and T-Cre mesodermal drivers in combination with inactivate Tbx1 and found reduction or loss of branchiomeric muscles from PA1. These mechanistic studies inform us that Tbx1 is required upstream of key myogenic genes needed for core mesoderm cell survival and fate, between E9.5 and E10.5, resulting in formation of the branchiomeric muscles.
Secret Agencies: The Communicative Constitution of a Clandestine Organization

This special issue challenges scholars to consider the theoretical, methodological, and practical implications of viewing organizations as ‘constituted in and through human communication.’ Interrogating the work of one of the most influential approaches to the study of the constitutive nature of organizing, the oeuvre of James Taylor and his colleagues or what has become known as the Montreal School, we identify an implicit assumption of organizational transparency. We suggest that unpacking ‘the transparency principle’ helps build a richer framework that builds upon the foundations of the Montreal School, facilitates empirical inquiry, and highlights several aspects of the social context which are typically taken for granted within organizational studies. Expanding Taylor et al.’s orientation to clandestine organizations, we address the question posed by the editors in the call for papers: ‘How does a communication-as-constitutive of organization’s perspective shape understandings of the organization’s e...
Mindfulness training modifies subsystems of attention.

Mindfulness is defined as paying attention in the present moment. We investigate the hypothesis that mindfulness training may alter or enhance specific aspects of attention. We examined three functionally and neuroanatomically distinct but overlapping attentional subsystems: alerting, orienting, and conflict monitoring. Functioning of each subsystem was indexed by performance on the Attention Network Test (ANT; Fan, McCandliss, Sommer, Raz, & Posner, 2002). Two types of mindfulness training (MT) programs were examined, and behavioral testing was conducted on participants before (Time 1) and after (Time 2) training. One training group consisted of individuals naive to mindfulness techniques who participated in an 8-week mindfulness-based stress reduction (MBSR) course that emphasized the development of concentrative meditation skills. The other training group consisted of individuals experienced in concentrative meditation techniques who participated in a 1-month intensive mindfulness retreat. Performance of these groups was compared with that of control participants who were meditation naive and received no MT. At Time 1, the participants in the retreat group demonstrated improved conflict monitoring performance relative to those in the MBSR and control groups. At Time 2, the participants in the MBSR course demonstrated significantly improved orienting in comparison with the control and retreat participants. In contrast, the participants in the retreat group demonstrated altered performance on the alerting component, with improvements in exogenous stimulus detection in comparison with the control and MBSR participants. The groups did not differ in conflict monitoring performance at Time 2. These results suggest that mindfulness training may improve attention-related behavioral responses by enhancing functioning of specific subcomponents of attention. Whereas participation in the MBSR course improved the ability to endogenously orient attention, retreat participation appeared to allow for the development and emergence of receptive attentional skills, which improved exogenous alerting-related process.
Fatigue Failure and Molecular Machine Design

Sophisticated molecular machines have evolved in nature, and the first synthetic molecular machines have been demonstrated. With our increasing understanding of individual operating cycles, the question of how operation can be sustained over many cycles comes to the forefront. In the design of macroscale machines, performance and lifetime are opposing goals. Similarly, the natural evolution of biological nanomachines, such as myosin motor proteins, is likely constrained by lifetime requirements. Rather than bond rupture at high forces, bond fatigue under repeated small stresses may limit the mechanical performance of molecular machines. Here, the effect of cyclic stresses using single and double bonds as simple examples are discussed. Additionally, it is demonstrated that an increase in lifetime requires a reduction in mechanical load and that molecular engineering design features, such as polyvalent bonds capable of rebinding, can extend the bond lifetime dramatically. A universal scaling law for the force output of motors is extrapolated to the molecular scale to estimate the design space for molecular machines.
A shift-invariant discrete wavelet transform

This article presents a unifying approach to the derivation and implementation of a shift-invariant wavelet transform of one- and two-dimensional (1-D and 2-D) discrete signals. Starting with Mallat's (1989) multiresolution wavelet representation (MRWAR), it presents an analytical process through which a shift-invariant, orthogonal, discrete wavelet transform called the multiscale wavelet representation (MSWAR) is obtained. The coefficients in the MSWAR are shown to be inclusive of those in the MRWAR with the implication that the derived representation is invertible. The computational complexity of the MSWAR is quantified in terms of the required convolutions, and its implementation is shown to be equivalent to the filter upsampling technique.
Estrogenic Compounds Are Not Always Cardioprotective and Can Be Lethal in Males with Genetic Heart Disease

Hypertrophic cardiomyopathy (HCM) is more severe in male than female mice eating a soy-based diet. We sought to determine whether the detrimental effects are mediated by the phytoestrogens present in soy, the mechanism by which phytoestrogens act, and to test whether estrogen modulates the sexually dimorphic phenotype. A soy-free diet (casein based) supplemented with the predominant phytoestrogens in soy, genistein and daidzein, recapitulated the fibrotic, proapoptotic and negative hemodynamic effects of soy in male hearts. As with the soy diet, the hearts of female HCM mice were not negatively affected by the phytoestrogen-containing diet. To determine the role of estrogen in the sex differences mediated by diet in HCM, gonadectomies were performed and estrogen was administered to male and female HCM mice on a casein- or phytoestrogen-supplemented diet. Somewhat surprisingly, estrogen was not protective in male or female mice with HCM and, in fact, was lethal in phytoestrogen-fed male mice with HCM. Because genistein is a potent tyrosine kinase inhibitor and tyrosine kinase inhibition has been associated with cardiotoxicity, we tested its effects in isolated adult cardiac myocytes. Genistein inhibited different tyrosine kinases depending on sex and, in combination with estrogen, resulted in apoptosis only in adult male cardiac myocytes. Finally, we show that phytoestrogens led to distinct programs of gene expression in hearts from males vs. females with HCM, suggesting mechanisms by which males are more sensitive to the detrimental effects of phytoestrogens and females are protected. These results implicate the phytoestrogen genistein in mediating cardiac pathology in males with HCM and, importantly, establish that estrogen is not protective in the setting of HCM.
Interactive animation and visualization in a virtual soil mechanics laboratory

With the advances in information technology over the last decade, the traditional teaching format of having an individual lecture to an audience has been supplemented and, in some cases, replaced by the rapid development and implementation of new distance learning methods. As technology rapidly changes, the importance of educating and training diverse populations of construction science students become more critical. It has become relatively easy to develop Web-based course materials for courses that do not have laboratory components. However, technology is currently available that allows for the development of virtual laboratories. It is now possible to develop laboratory courseware that can simulate very sophisticated and costly equipment and reach larger sections of the student population. The paper demonstrates a Web-based interactive virtual soil mechanics laboratory for construction science. The main elements of the presented approach are: a means of assimilating the students' interactive learning knowledge and behavior, representation of the instructor's guidance and assessment knowledge, and utilization of motivational techniques such as multimedia, animation and Java simulation of laboratory soil tests. The presented paper illustrates some of the laboratory soil tests that are simulated with multimedia interaction and visualization techniques for enhancing the student's subject visualization and conceptual understanding in soil mechanics.
Establishment and Characterization of an Air-Liquid Canine Corneal Organ Culture Model To Study Acute Herpes Keratitis

Despite the clinical importance of herpes simplex virus (HSV)-induced ocular disease, the underlying pathophysiology of the disease remains poorly understood, in part due to the lack of adequate virus–natural-host models in which to study the cellular and viral factors involved in acute corneal infection. We developed an air-liquid canine corneal organ culture model and evaluated its susceptibility to canine herpesvirus type 1 (CHV-1) in order to study ocular herpes in a physiologically relevant natural host model. Canine corneas were maintained in culture at an air-liquid interface for up to 25 days, and no degenerative changes were observed in the corneal epithelium during cultivation using histology for morphometric analyses, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) assays, and transmission electron microscopy (TEM). Next, canine corneas were inoculated with CHV-1 for 48 h, and at that time point postinfection, viral plaques could be visualized in the corneal epithelium and viral DNA copies were detected in both the infected corneas and culture supernatants. In addition, we found that canine corneas produced proinflammatory cytokines in response to CHV-1 infection similarly to what has been described for HSV-1. This emphasizes the value of our model as a virus–natural-host model to study ocular herpesvirus infections. IMPORTANCE This study is the first to describe the establishment of an air-liquid canine corneal organ culture model as a useful model to study ocular herpesvirus infections. The advantages of this physiologically relevant model include the fact that (i) it provides a system in which ocular herpes can be studied in a virus–natural-host setting and (ii) it reduces the number of experimental animals needed. In addition, this long-term explant culture model may also facilitate research in other fields where noninfectious and infectious ocular diseases of dogs and humans are being studied.
Pharmacological characterization of the P2 receptors profile in the podocytes of the freshly isolated rat glomeruli

Calcium flux in the podocytes is critical for normal and pathophysiological regulation of these types of cells, and excessive calcium signaling results in podocytes damage and improper glomeruli function. Purinergic activation of P2 receptors is a powerful and rapid signaling process; however, the exact physiological identity of P2 receptors subtypes in podocytes remains essentially unknown. The goal of this study was to determine the P2 receptor profile in podocytes of the intact Sprague-Dawley rat glomeruli using available pharmacological tools. Glomeruli were isolated by differential sieving and loaded with Fluo-4/Fura Red cell permeable calcium indicators, and the purinergic response in the podocytes was analyzed with ratiometric confocal fluorescence measurements. Various P2 receptors activators were tested and compared with the effect of ATP, specifically, UDP, MRS 2365, bzATP, αβ-methylene, 2-meSADP, MRS 4062, and MRS 2768, were analyzed. Antagonists (MRS 2500, 5-BDBD, A438079, and NF 449) were tested when 10 μM ATP was applied as the EC50 for ATP activation of the calcium influx in the podocytes was determined to be 10.7 ± 1.5 μM. Several agonists including MRS 2365 and 2-meSADP caused calcium flux. Importantly, only the P2Y1-specific antagonist MRS 2500 (1 nM) precluded the effects of ATP concentrations of the physiological range. Immunohistochemical analysis confirmed that P2Y1 receptors are highly expressed in the podocytes. We conclude that P2Y1 receptor signaling is the predominant P2Y purinergic pathway in the glomeruli podocytes and P2Y1 might be involved in the pathogenesis of glomerular injury and could be a target for treatment of kidney diseases.
Differentiating aspen and cottonwood in prehistoric wood from Chacoan great house ruins

Accurate taxonomic identification is an essential part of archaeological wood analysis. However, making identifications more precise than the genus level is usually not possible since species within the same genus typically possess very similar cellular morphology. This paper describes a method for distinguishing aspen (Populus tremuloides) from cottonwood (Populus fremontii, Populus angustifolia, Populus acuminata) in samples of wood collected from the San Juan Basin in northwestern New Mexico and southwestern Colorado. This method is then applied to archaeological wood samples from the Anasazi great house at Aztec Ruins National Monument in Aztec, New Mexico. The results of this study demonstrate that quantifiable differences do exist between aspen and cottonwood species and that the technique can be used to separate archaeological specimens of Populus wood.
A comparison of two zooplankton time series data collected in the Gulf of Maine

Interannual and seasonal trends of zooplankton abundance and species composition were compared between the Bongo net and Continuous Plankton Recorder (CPR) time series in the Gulf of Maine. Data from 5799 Bongo and 3118 CPR samples were compared from the years 1978 – 2006. The two programs use different sampling methods, with the Bongo time series composed of bimonthly vertically integrated samples from locations throughout the region, while the CPR was towed monthly at 10 m depth on a transect that bisects the region. It was found that there was a significant correlation between the interannual (r ¼ 0.67, P , 0.01) and seasonal (r ¼ 0.95, P , 0.01) variability of total zooplankton counts. Abundance rankings of individual taxa were highly correlated and temporal trends of dominant copepods were similar between samplers. Multivariate analysis also showed that both time series equally detected major shifts in community structure through time. However, absolute abundance levels were higher in the Bongo and temporal patterns for many of the less abundant taxa groups were not similar between the two devices. The different mesh sizes of the samplers probably caused some of the discrepancies; but diel migration patterns, damage to soft bodied animals and avoidance of the small CPR aperture by some taxa likely contributed to the catch differences between the two devices. Nonetheless, Bongo data presented here confirm the previously published patterns found in the CPR data set, and both show that the abundance increase of the 1990s has been followed by average to below average levels from 2002 to 06.