cssi/SciSciGPT-SciSciNet huggingface dataset:
Approximating cycles in a shortest basis of the first homology group from point data

Inference of topological and geometric attributes of a hidden manifold from its point data is a fundamental problem arising in many scientific studies and engineering applications. In this paper, we present an algorithm to compute a set of cycles from a point data that presumably sample a smooth manifold M ⊂ ℝ d . These cycles approximate a shortest basis of the first homology group H 1 (M) over coefficients in the finite field ℤ 2 . Previous results addressed the issue of computing the rank of the homology groups from point data, but there is no result on approximating the shortest basis of a manifold from its point sample. In arriving at our result, we also present a polynomial time algorithm for computing a shortest basis of H 1 (K) for any finite simplicial complex K whose edges have non-negative weights.
Marketing managers need more than forecasting accuracy

Abstract In theory, time series models can provide more accurate predictions than econometric models. However, time series models do so by introducing bias. To marketing managers who are interested in planning as well as forecasting, lack of bias is more important than accuracy.
Effective DQE (eDQE) for monoscopic and stereoscopic chest radiography imaging systems with the incorporation of anatomical noise

Purpose: Stereoscopic chest biplane correlation imaging (stereo/BCI) has been proposed as an alternative modality to single view chest x-ray (CXR). The metrics effective modulation transfer function (eMTF), effective normalized noise power spectrum (eNNPS), and effective detective quantum efficiency (eDQE) have been proposed as clinically relevant metrics for assessing clinical system performance taking into consideration the magnification and scatter effects. This study compared the metrics eMTF, eNNPS, eDQE, and detectability index for stereo/BCI and single view CXR under isodose conditions at two magnifications for two anthropomorphic phantoms of differing sizes. Methods: Measurements for the eMTF were taken for two phantom sizes with an opaque edge test device using established techniques. The eNNPS was measured at two isodose conditions for two phantoms using established techniques. The scatter was measured for two phantoms using an established beam stop method. All measurements were also taken at two different magnifications with two phantoms. A geometrical phantom was used for comparison with prior results for CXR although the results for an anatomy free phantom are not expected to vary for BCI. Results: Stereo/BCI resulted in improved metrics compared to single view CXR. Results indicated that magnification can potentially improve the detection performance primarily due to the air gap which reduced scatter by ∼20%. For both phantoms, at isodose, eDQE(0) for stereo/BCI was ∼100 times higher than that for CXR. Magnification at isodose improved eDQE(0) by ∼10 times for stereo/BCI. Increasing the dose did not improve eDQE. The detectability index for stereo/BCI was ∼100 times better than single view CXR for all conditions. The detectability index was also not improved with increased dose. Conclusions: The findings indicate that stereo/BCI with magnification may improve detectability of subtle lung nodules compared to single view CXR. Results were improved with magnification for the smaller phantom but not for the larger phantom. The effective DQE and the detectability index did not improve with increasing dose.
High-order Newton-Cotes integration methods in scattering theory

We have implemented high-order Newton-Cotes integration formulas through 16th order for use in the integral equation formulation of scattering theory. We have found that the high-order integration rules give high accuracy results with fewer grid points than low-order rules. Use of Newton-Cotes formulas beyond 16th order was prohibited by numerical instabilities. These formulas were applied to both a model integral and to the calculation of the photoionization of N2 leading to the (2σu)−1B2Σu+ and (3σg)−1 X2Σg+ states of N2+ at a photon energy of 34 eV. High-order rules were found to be unstable when applied to the integration of functions which rise as r21 + 2 at high 1 in the partial wave expansions. An empirical formula is presented which predicts when high-order rules diverge as a function of l in a given integration region. Using a combination of high and low-order rules eliminated the divergence and still yielded accurate results in the N2 photoionization calculations. Results for the photoionization of N2 showed that Simpson's rule is the most efficient Newton-Cotes formula for calculations in which the desired error was larger than 0.14%. For smaller errors, high-order integration rules are more efficient.
The effects of hibernation on the chemical composition of cerebrospinal and intraocular fluids, blood plasma and brain tissue of the woodchuck (Marmota monax)

Abstract 1. 1. Blood plasma and ocular (IOFs) and cerebrospinal fluids (CSFs) from hibernating and nonhibernating (anaesthetized) woodchucks were assayed for the following constituents: Na+, K+, Mg2+, Ca2+, glucose, lactate, ascorbate, total α-amino N, glutamine, glutamate and protein concentrations and total osmolarity. Water and electrolyte content of brain gray and white matter were also determined. 2. 2. During hibernation, the [Mg2+] of plasma and CSFs, but not of IOFs, was greatly elevated; [glucose] and [lactate] were significantly lowered, while [ascorbate] was maintained at a concentration well above that of plasma. 3. Plasma [K+] of hibernating woodchucks was similar to that of active (excited) animals but significantly higher than that of resting or anaesthetized normothermic animals. [K+] of cortical subarachnoid fluid was nearly doubled in the early phase of hibernation, but that of other fluids remained essentially normal. 3. 4. Brain [K+] and [Mg2+] were significantly decreased in hibernation without a concomitant increase in [Na+]. 4. 5. It is concluded that active transport of some solutes across the blood-brain and blood-ocular barriers continues during hibernation. 5. 6. The effects of hibernation on brain electrolytes are not consistent with a cold-induced Na-K shift, but are consistent with the possiblility that the cerebral cortex undergoes physiological changes in hibernation similar to those thought to occur in acute cortical shutdown.
Suggested improvements to the DoDAF for modeling architectural security

Currently the DoDAF v1.5 states that security measures are "[...] being scoped for subsequent DoDAF versions [...]". [4] With little else said in the documentation it is difficult to tell what the Department of Defense deems important to the security of their system architecture. Proper software architecture should not only produce extensible, scalable, reusable code, it should inject security into the very core of the system. If DoDAF architectures are to be used on enterprise-wide net-centric applications, security cannot be an afterthought. This paper uses some existing modifications that have been suggested as separate additions, provides a way to integrate them into the DoDAF and suggests templates for new views as well as modifications to any existing templates.
A perspective into ligand-receptor affinities using complex numbers

Abstract The binding of ligands by a receptor can be expressed in an equation derived by a thermodynamic stoichiometric approach in which the stoichiometric equilibrium constants are all positive and real. An alternative binding equation can be derived algebraically in which the equilibrium constants can have values that are complex numbers. Some consequences of this situation are explored, and numerical values of the ghost equilibrium constants are evaluated for a number of ligand-receptor complexes.
Control of megakaryocyte-specific gene expression by GATA-1 and FOG-1: role of Ets transcription factors.

The transcription factor GATA-1 and its cofactor FOG-1 are essential for the normal development of erythroid cells and megakaryocytes. FOG-1 can stimulate or inhibit GATA-1 activity depending on cell and promoter context. How the GATA-1–FOG-1 complex controls the expression of distinct sets of gene in megakaryocytes and erythroid cells is not understood. Here, we examine the molecular basis for the megakaryocyte-restricted activation of the αIIb gene. FOG-1 stimulates GATA-1-dependent αIIb gene expression in a manner that requires their direct physical interaction. Transcriptional output by the GATA-1–FOG-1 complex is determined by the hematopoietic Ets protein Fli-1 that binds to an adjacent Ets element. Chromatin immunoprecipitation experiments show that GATA-1, FOG-1 and Fli-1 co-occupy the αIIb promoter in vivo. Expression of several additional megakaryocyte-specific genes that bear tandem GATA and Ets elements in their promoters also depends on the physical interaction between GATA-1 and FOG-1. Our studies define a molecular context for transcriptional activation by GATA-1 and FOG-1, and may explain the occurrence of tandem GATA and Ets elements in the promoters of numerous megakaryocyte-expressed genes.
Altered in vitro immune response to hypoxia-treated normal peritoneal fibroblasts

Hypoxia treatment of normal peritoneal fibroblasts results in alterations that are characteristic for fibroblasts obtained from postoperative peritoneal adhesion tissue. In this study, we have shown that hypoxia treatment enhances normal peritoneal fibroblast elimination by lymphokine-activated killer cells to the level of adhesion tissue fibroblasts, suggesting a pivotal role of hypoxia in the adhesion development.
Quadratic Stark Shifts of Zeeman Levels in Alkali Atoms

An atomic-beam magnetic-resonance apparatus was used to measure the difference in the quadratic Stark shifts of Zeeman levels in the ground states of Na and K. The results of this work are reported. Also, previously reported related work is discussed.
Muslim Cultural Entrepreneurs and the Democracy Debate

Although there are few points of consensus in modern social science, the incompatibility of Islam and democracy is a candidate for one of them. Many Western scholars, only a few of whom have any pa...
Control of Machine Tools

Control of machine tools is a relatively new field that started in the early 1950s with the invention of the Numerically Con­ trolled (NC) machine tool by John Parsons in Traverse City, MI, with subcontract to the MIT Servomechanism Laboratory [14]. Despite the importance of this invention, the rate of pene­ tration of NC in the U.S. was very slow. The major advance in NC occurred in the early 1970's with the introduction of Com­ puter Numerical Control (CNC) in which a dedicated computer replaced most of the digital hardware control boards of the NC. Approximately at the same time, a few companies (e.g., Bendix [54]) started to develop adaptive control (AC) systems for ma­ chine tools. One of the early CNC/AC machines, developed by J. Tlusty and Y. Koren in 1973 [63], utilized an HP-2100 com­ puter as the controller that runs both the conventional CNC and the AC programs. A typical control software of CNC systems has two major portions: the servo-control (Level I) and the interpolator (Level II) which coordinates the machine axial motions. The AC pro­ gram along with other error compensation programs are located at a higher level (Level 3) of the control hierarchy. Level 4 is usually regarded as a supervisory level that receives feedback from measurements of the finished part or from other control­ lers. This general multi-level control architecture is depicted in Fig. 1. Accordingly, the following sections review the advances in servocontrol, interpolators, and adaptive control/compensa­ tion methods.
Inverting the MYEGA equation for viscosity

Abstract The Mauro–Yue–Ellison–Gupta–Allan (MYEGA) viscosity expression was recently suggested as an effective three-parameter representation for liquid viscosity as a function of temperature, competitive with the popular Vogel–Fulcher–Tammann (VFT) expression and arguably superior to it, especially at low temperatures. Unlike the VFT function, the MYEGA function cannot be analytically inverted to give temperature as a function of viscosity. This letter describes a simple mathematical trick for inverting the MYEGA equation to solve for temperature as a function of viscosity. It is shown that the solution requires a well-studied transcendental equation involving the Lambert W-function.
Response suppression after transfer from shock-escape to thirst-motivated training

In a 6-ft runway, rats were given 15 shock-escape trials, or none, followed by various transfer conditions. Shock-escape followed by thirst-motivated training resulted in response suppression which was unaffected by a view of water from the runway, was not due to reduced attraction to water, and was not an exclusive function of prior shock experience.
Laparoscopic revision of failed open bariatric procedures.

Background: Roux-en-Y gastric bypass (RYGB) is considered the surgical procedure of choice for morbid obesity. Patients who fail to meet weight loss goals after restrictive or malabsorptive surgery can be offered revision. We present five cases in which prior open bariatric procedures were revised laparoscopically. Patients: Five patients presented for laparoscopic revision having regained weight after initial success with prior bariatric surgery. Results: Preoperative body mass index averaged 46 kg/m2. Average operative time was significantly longer (344 min) than we had experienced with 56 primary RYGB during the same 4-month period (206 min). In one patient, a stricture had developed at the gastrojejunostomy requiring endoscopic dilation. There were no other complications and no deaths. All the patients had lost weight at the 6-month follow-up assessment. Conclusions: Laparoscopic revision of failed open bariatric procedures, although requiring longer operative times than primary RYGB, can be performed safely in the hands of an experienced minimally invasive surgeon.
AVERSIVE ASPECTS OF A FIXED‐INTERVAL SCHEDULE OF FOOD REINFORCEMENT1

The key pecking of pigeons was reinforced according to a fixed-interval schedule of reinforcement. The pigeons were also given the opportunity to attack a restrained target pigeon. The attack rates during the sessions of fixed-interval reinforcement were higher than during the operant level sessions in four of the five pigeons. Most attack occurred during the post-reinforcement pause in key pecking. It was suggested that a fixed-interval schedule of positive reinforcement possesses aversive properties, the most aversive of which are located during the post-reinforcement pause.
Missionary Kid Career Development: A Consensual Qualitative Research Investigation Through a Social Cognitive Lens

Repatriated, young adult children of international missionaries (missionary kids [MKs]) face unique challenges in education and career development. The authors conducted a consensual qualitative research investigation, grounded in social cognitive theory (Bandura, 1986), as it informs social cognitive career theory, of career planning and decision making with 11 repatriated MKs. Participants ranged in age from 19 to 23 years (58% female, 67% Caucasian) and had repatriated to the United States between the ages of 14 and 19 years, spending between 4 and 19 years abroad. The authors’ interpretation of the study findings led to a contextspecific revision of Bandura’s (1986) Triadic Reciprocality Model. That is, regarding career development, faith intersects environmental variables, personal attributes, and overt behaviors in unexpected and multidimensional ways. Recommendations for researchers and practitioners include (a) attending to issues of sociocultural adaptation, (b) continuing to offer empirically supported (standard) career services to MKs, (c) using contextual and developmental approaches, and (d) inquiring about faith and calling.
Effect of interposed abdominal compression during CPR on central arterial and venous pressures

Despite the problems inherent in estimating blood flow from pressure, determination of systolic arterial pressure during cardiopulmonary resuscitation (CPR) is common and probably valuable as an indicator of potential systemic flow. The addition of interposed abdominal compression (IAC) to closed-chest CPR has been promoted because of its potential to increase systolic arterial pressure during CPR. Interposed abdominal compressions have also reportedly increased diastolic arterial-central venous pressure difference (DA-DCVP) and, thus, have the potential to increase coronary vascular flow. Two distinct methods of CPR were studied in conjunction with IAC. In six humans, there was no significant increase late in the resuscitative process in systolic arterial pressure or in DA-DCVP difference with IAC as compared with the two methods of CPR studied without IAC.
Clofarabine Combined with Busulfan Provides Excellent Disease Control in Adult Patients with Acute Lymphoblastic Leukemia Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

We investigated the safety and early disease control data for i.v. busulfan (Bu) in combination with clofarabine (Clo) in patients with acute lymphoblastic leukemia undergoing allogeneic hematopoietic stem cell transplantation (SCT). Fifty-one patients (median age, 36 years; range, 20-64 years) received a matched sibling (n = 24), syngeneic (n = 2), or matched unrelated donor transplant (n = 25) for acute lymphoblastic leukemia in first complete remission (n = 30), second complete remission (n = 13), or active disease (n = 8). More than one-half of the patients had a high-risk cytogenetic profile, as defined by the presence of t(9;22) (n = 17), t(4;11) (n = 3), or complex cytogenetics (n = 7). Clo 40 mg/m2 was given once daily, with each dose followed by pharmacokinetically dosed Bu infused over 3 hours daily for 4 days, followed by hematopoietic SCT 2 days later. The Bu dose was based on drug clearance, as determined by the patient's response to a 32-mg/m2 Bu test dose given 48 hours before the high-dose regimen. The target daily area under the receiver-operating characteristic curve was 5500 μM/min for patients age
A new approach to nonfrontal face recognition

Global face recognition methods based on projection (such as principal component analysis) exhibit a well-known sensitivity to face pitch and yaw variations. This paper introduces and tests a new approach to the normalization of "off-frontal" face images and applies it in a principal component analysis (PCA) framework. Our proposed normalization employs two affine transformations of triangular face regions to register selected facial features. Experiments with the technique demonstrate performance improvements over a traditional normalization method when the proposed normalization step is employed. This experiment reports the results based on an image data set containing 665 images of 269 subjects photographed with noticeable face yaw, plus up to 1100 additional training images of subjects with frontal face pose.
Microstructure of sheared monosized colloidal suspensions resulting from hydrodynamic and electrostatic interactions.

Hydrodynamic and near-particle interactions in sheared suspensions are communicated through suspension microstructure to produce a wide variety of rheological behaviors. To characterize this microstructure, the individual positions of monosized silica particles flowing through a microchannel are obtained with near simulation-level detail. The pair distribution functions of the microstructure at moderate to high Peclet number shear rates are very similar to previous numerical studies. Viscometric functions calculated based on the detailed microstructure obtained through this technique show qualitative agreement with computational results. These results elucidate the origins of shear-thickening of suspensions at high shear rates. While efforts are taken to screen electrostatic interactions to study hydrodynamic and Brownian interactions, the role of electrostatic interaction between particles is also investigated by reducing suspension ionic strength. These non-hydrodynamic electrostatic interactions result in a loss of anisotropy that generally agrees with previous findings of “soft” particle systems.
The effects of norms and self-reward on goal setting and subsequent behavior

Early laboratory studies utilizing relatively meaningless tasks, e.g., turning a wheel (Bandura & Perloff, 1967) and solving simple addition problems (Speidel, 1974), found positive effects as a function of self-reinforcement. In contrast, Kirsch, Heatherington, and Colapietro (1979) found detrimental effects of self-reward utilizing a task (solving anagrams) that differed from those in earlier studies in two ways: (1) it required greater cognitive involvement, and (2) it was presented to subjects as a test of problem-solving skills. Kirsch et al. found that subjects who were provided with normative information, asked to set achievement goals, and instructed to reward themselves with money for each anagram solved attempted fewer problems, spent less time at the task, and achieved fewer correct solutions than subjects who were rewarded noncontingently or who were not rewarded at all. However, the normative information provided to subjects in that study was revealed to be inaccurately low. The present experiment was designed to assess whether the negative effects obtained by Kitsch et al. were limited to situations in which inaccurate normative information is provided to subjects. A total of 120 subjects were tested on an anagrams task described as a test of skill. Three levels of normative information (no norms, low norms, and accurate norms) were crossed with two levels of reward (contingent and noncontingent). In n o n o r m s conditions, no normative information was provided. L o w n o r m s subjects were informed that in previous years,
Maximum impact for minimum subsidy: reverse auctions for universal access in Chile and India

Purpose – The purpose of this article is to discuss how minimum subsidy auctions have been implemented in Chile and India for Internet and mobile phone infrastructure to and identify lessons for governments considering reverse auctions as a tool. In a minimum subsidy auction (also known as a reverse auction), the government starts by offering the maximum funds available for a given public project; the company requiring smallest subsidy wins. Design/methodology/approach – The article investigates several case studies of subsidy auctions in both Chile and India. Findings – When firms compete for subsidies in reverse auctions, they have incentives to get the most result for the least funds. This furthers the government’s goal to achieve maximum public policy impact with minimum budget. Originality/value – For developing countries, very little research has been done on implementation of auctions in the communications sector.
Enhancing Social Support at the Workplace: Assessing the Effects of the Caregiver Support Program

Although the health-enhancing effects of social support have been well documented, little is known about how to increase the flow of social support among network members. This article describes and evaluates the Caregiver Support Program, a worksite program that attempts to improve the quality of work relationships among house managers and direct care staff who work in group homes for the developmentally disabled. The program incorporates three strategies for increasing social support: (1) adding a new person or group of persons to the employee's social network, (2) enhancing existing relationships by improving the focal employee's skills for maintaining strong networks and mobilizing support, and (3) enhancing existing relationships by training members of the employee's social network in ways to be more supportive. The Caregiver Support Program was evaluated in a randomized field trial. Results indicate that the program was effective in improving the relationships between direct care staff participants and their house managers. However, other work relationships remained unaffected. The relationship between direct care staff and their house managers was the only work relationship for which both members of the interpersonal dyad participated in the program. The implications of these findings for health education practice and future research are discussed.
Rapid trade-space realization of IR missile seeker design with a dynamic performance model

Tactical air-to-air or ground-to-air IR missile seeker design involves a vast number of interrelated design criteria spread over a very large parameter space. To further exacerbate matters, many of these critical parameters are dynamic in nature. A common approach to seeker design is to model the behavior of each critical component, or set of components, with a mathematical simulation of its predicted behavior. While this approach is generally very high in fidelity, it tends to be very computationally (and man-hour) intensive, requiring a large number of iterations for each component. Furthermore, many of these modeled components, for example, signal processing, are both space- and time-dependent in nature, and hence are dynamically related to the missile flyout (dynamics) model; consequently, they cannot be fully modeled by a purely static model. An end-to-end (launch to closest approach) dynamic seeker performance model is briefly described herein, which allows for rapid trade space realization over all relevant seeker parameters, and an example seeker design flowdown using the dynamic performance model is presented.
Poster abstract: ASWP: a long-term WSN deployment for environmental monitoring

ASWP testbed, a long-term wireless sensor network (WSN) deployment for environmental monitoring, is presented. This testbed integrates 42 MICAz nodes that implement a periodic sampling application for external sensors exposed to a forested nature reserve at the Audubon Society of Western Pennsylvania (ASWP), USA. It has been running for the past two years using TinyOS-based platforms and the commercially available routing software XMesh. Network performance analysis indicates that the critical impact due to the outdoor environment and node physical failures significantly reduced the network yield when long-term periods were considered. In particular, it is found that an over-used routing path across the network was responsible for most of the packet retransmitted and dropped in ASWP. This preliminary work intends to provide a useful reference point for WSN research and development targeted towards outdoor WSNs for long-term deployments.
Strong local diagnosability of (n,k)-star graphs and Cayley graphs generated by 2-trees with missing edges

Abstract In this paper, we study the local diagnosability and strong local diagnosability properties for ( n , k ) -star graphs and Cayley graphs generated by 2-trees. Moreover, we also consider the corresponding problem with missing edges.
A Hydrogen-Bonding Based Approach to Fabricate Polymer/Inorganic Nanoparticle Multilayer Film

A new hydrogen-bonding based route for layer-by-layer fabrication of polymer/inorganic nanoparticle multilayer thin films was developed. Surface modification of inorganic nanoparticles can provide functional groups on the particle surface, e.g. pyridine, carboxyl, and flavin. A polymer/inorganic nanoparticle multilayer film can be fabricated in a layer-by-layer manner using the hydrogen-bonding interaction between the functional groups on the surface of nanoparticles and polymers. The multilayer buildup was monitored by UV-visible spectroscopy, which showed a linear increase of the film absorbance with the number of adsorbed nanoparticle layers. FTIR spectroscopy was used to verify hydrogen bonding between polymer and nanoparticles, which is believed to be the driving force for the formation of polymer/nanoparticle multilayer thin films.
The Deuteron matter radius

Abstract The deuteron matter radius r m calculated for most realistic nucleon-nucleon potentials fitting the experimental triplet scattering length is about 1% larger than the experimental value, or 0.6% larger than a “shape-independent” value in the effective-range expansion. However, it is 2.6% larger than experiment for the full Bonn potential. We find that this is caused by the energy dependence of the full Bonn potential induced by the 3.8% admixture of abnormal components involving higher-mass states. A correction to r m of about −1.8% is found to be necessary to allow for the smaller sizes of these abnormal components, thus bringing the Bonn result in line with the other realistic potentials. The explicit appearance of the D-state in realistic potential models of the deuteron is shown to increase r m by 0.8%. Reductions of r m made with the help of phase-equivalent unitary scale transformations show significant redistributions of the matter density inside a two-nucleon separation of 3 fm. Such redistributions will reduce the size of the neutron electric form factor deduced from e-D scattering.
Comprehensive coastal circulation model with application to the Gulf of Maine

Abstract A state-of-the-art finite element model is described and applications are shown for the Gulf of Maine. The model is three-dimensional (hydrostatic) with a free surface, fully nonlinear, incorporates advanced turbulence closure and operates in tidal time. Variable horizontal and vertical resolution are facilitated by the use of unstructured meshes. Solutions for the Gulf of Maine illustrate performance in the context of several isolated nonlinear processes. Composite solutions for March–April and July–August time periods are recorded under climatological forcing. The solutions exhibit a general cyclonic central Gulf circulation, a coastal current with several branch points and anticyclonic circulation around Georges Bank. Each of these features is seasonally modulated. The surface circulation is in general agreement with surface drift observations. The circulation at depth shows the combined influence of deep basin topography and baroclinicity.
Robust root clustering for linear uncertain systems using generalized Lyapunov theory

Consideration is given to the problem of matrix root clustering in subregions of a complex plane for linear state space models with real parameter uncertainty. The nominal matrix root clustering theory of Gutman & Jury (1981) using the generalized Liapunov equation is extended to the perturbed matrix case, and bounds are derived on the perturbation to maintain root clustering inside a given region. The theory makes it possible to obtain an explicit relationship between the parameters of the root clustering region and the uncertainty range of the parameter space.
CstF-64 is necessary for endoderm differentiation resulting in cardiomyocyte defects.

Although adult cardiomyocytes have the capacity for cellular regeneration, they are unable to fully repair severely injured hearts. The use of embryonic stem cell (ESC)-derived cardiomyocytes as transplantable heart muscle cells has been proposed as a solution, but is limited by the lack of understanding of the developmental pathways leading to specification of cardiac progenitors. Identification of these pathways will enhance the ability to differentiate cardiomyocytes into a clinical source of transplantable cells. Here, we show that the mRNA 3′ end processing protein, CstF-64, is essential for cardiomyocyte differentiation in mouse ESCs. Loss of CstF-64 in mouse ESCs results in loss of differentiation potential toward the endodermal lineage. However, CstF-64 knockout (Cstf2E6) cells were able to differentiate into neuronal progenitors, demonstrating that some differentiation pathways were still intact. Markers for mesodermal differentiation were also present, although Cstf2E6 cells were defective in forming beating cardiomyocytes and expressing cardiac specific markers. Since the extraembryonic endoderm is needed for cardiomyocyte differentiation and endodermal markers were decreased, we hypothesized that endodermal factors were required for efficient cardiomyocyte formation in the Cstf2E6 cells. Using conditioned medium from the extraembryonic endodermal (XEN) stem cell line we were able to restore cardiomyocyte differentiation in Cstf2E6 cells, suggesting that CstF-64 has a role in regulating endoderm differentiation that is necessary for cardiac specification and that extraembryonic endoderm signaling is essential for cardiomyocyte development.
A note on the marginal tax rate in a finite economy

Abstract The marginal tax rate is shown to be non-negative in Guesnerie and Seade's model of nonlinear pricing in a finite economy under assumptions that are as mild as those customarily adopted in nonlinear tax models with a one-dimensional continuum population.
Three-dimensional geometric modeling of the cochlea

Three-dimensional geometric modeling of the human cochlea not only provides a basis for preoperative planning and postoperative evaluation of cochlear implantation, but also facilitates medical education and training. In this paper, the three-dimensional geometric modeling method of the cochlea has been developed. The central path of the cochlea is extracted from a spiral CT image volume by segmenting the cochlea and tracking through the cochlear canal. The central path is modeled by a helico-spiral. The first component in the helico- spiral model represents the projected central path onto a plane perpendicular to the modiolar axis, while the second component depicts the longitudinal stretching of the central path. A non-linear least square minimization based algorithm is devised for the identification of intrinsic and extrinsic parameters of the helico-spiral representation of the cochlea. Numerical phantoms with added different noise levels up to standard deviation of 2 mm are synthesized according to the average parameters of the human cochlea to evaluate the accuracy. In real human cochlear studies, our model fits into the modiolar axis and the central path very well, allowing the calculation of length, height and angular positions needed for frequency mapping of multi-channel cochlear implant electrodes.
Specific enhancement of cell aggregation in vitro.

Abstract A supernatant has been prepared from the culture medium of monolayer cultures of embryonic chick neural retina cells which enhanced the aggregation of freshly dissociated retina cells. The specificity of the supernatant was demonstrated by three independent tests: (1) cells from tissues other than retina did not respond to it; (2) the characteristic activity was not removed from the supernatant by liver cells, as it was by retina cells; and (3) antiserum prepared in rabbits against the supernatant, which modified the normal course of aggregation of retina cells, did not affect the aggregation of liver cells. Accumulation of the active component(s) in the supernatant was found to be inhibited by low temperature and by cycloheximide, an inhibitor of protein synthesis. The interaction of the active supernatant with dissociated retina cells has been experimentally separated into two phases: (1) specific uptake, which is independent of continuous metabolic activity of the cells, and (2) functional utilization, which requires protein synthesis. The evidence suggests that the active component(s) is taken up onto the cell surface and that materials immunologically cross-reactive with it are normally present there.
Annulment of aziridine (apholate)-induced growth inhibition in the estuarine flagellate Tetraselmis subcordiformis by some purines and pyrimidines.

SYNOPSIS. At 850 ppm apholate [2,2,4,4,6,6-hexakis (1-aziridinyl)-2,2,4,4,6,6-hexahydro-1,3,5,2,4,6-triazatriphosphorine], an insect chemosterilant, reduced growth of the marine flagellate Tetraselmis subcordiformis by 50% in 21 days. Mean cell volume more sensitively indicated cellular response at low apholate concentrations than cell number or biomass. Two other aziridinyl chemosterilants tested were 12 and 120 X more toxic than apholate—values agreeing with those reported for some estuarine animals. Apholate acted directly upon the organisms rather than indirectly on the experimental medium since comparatively small molar additions of orotic acid, adenine, guanine, and thymine to apholate-poisoned cultures annulled the growth inhibition. Determining the mode of action of aziridinyl chemosterilants by activity annulment is discussed.
The association of genetic polymorphisms in sex hormone biosynthesis and action with insulin sensitivity and diabetes mellitus in women at midlife.

Abstract We evaluated associations of insulin sensitivity, metabolic syndrome, and diabetes mellitus with single nucleotide polymorphism (SNP) variants from sex hormone biosynthesis and action in women of 4 races/ethnicities. DNA was extracted from transformed cell samples of 1,538 women in the Study of Women's Health Across the Nation (SWAN). African American, Caucasian, Chinese, and Japanese women in SWAN enrolled in the Sex Steroid Hormone Genetics Protocol from whom fasting glucose and insulin measures (for estimating insulin sensitivity), diabetes status, and metabolic syndrome classification were obtained. SNPs from the genes encoding aromatase ( CYP 19 ), 17β-hydroxysteroid dehydrogenase ( 17HSD ) type 1, and the estrogen receptors–α ( ESR1 ) and –β ( ESR2 ) were measured. The prevalence of metabolic syndrome was 20% in Chinese women, 22% in Japanese women, 28% in Caucasian women, and 43% in African American women. The prevalence of diabetes was 3% in Chinese women, 4% in Japanese women, 7% in Caucasian women, and 19% in African American women. Significant associations of CYP 19 genotypes and insulin sensitivity were observed in African American, Caucasian, and Japanese women. Selected ESR1 and ESR2 genotypes were associated with insulin sensitivity and metabolic syndrome only in Japanese and Chinese women. The strongest associations related 17HSD genotypes to diabetes in Caucasian women, with odds ratios ranging from 4.4 to 7.5 and confidence intervals that excluded the null value. We observed strong associations between variations in sex hormone biosynthesis and function genes with insulin sensitivity, the metabolic syndrome, and diabetes that varied by race/ethnicity. The strong association of 17HSD and diabetes in Caucasian women has not been previously reported and should be further investigated.
Extended Resection for Pancreatic Adenocarcinoma

Adenocarcinoma of the pancreas presents a number of therapeutic challenges. Given the poor long-term outcomes after pancreaticoduodenectomy (PD), many surgeons have sought to improve survival via a radical or "extended" pancreatectomy which may include (a) total pancreatectomy (TP), (b) extended lymph node dissection (ELND), and (c) portal/mesenteric vascular resections. These themes of "extended" resection are addressed in this review. TP should not be performed for most cases of adenocarcinoma of the pancreatic head because of the nominal incidence of lymph node involvement along the body and tail of the pancreas, the scarcity of multicentric disease, and the better management of pancreatic leaks after PD. Most studies show no difference in long-term survival and demonstrate greater postoperative morbidity after TP than after PD. Performing ELND in addition to PD is not worthwhile because most studies do not demonstrate any long-term benefits from ELND and the circumferential dissection around the mesenteric vessels required to harvest distant lymph nodes increases postoperative morbidity. Major arterial resection increases postoperative morbidity after PD and worsens long-term survival as the need for arterial resection to achieve negative resection margins indicates more aggressive disease. In contrast, portal and/or mesenteric venous resection does not increase the morbidity after PD or impact long-term survival as venous resection is often performed because of tumor location and not extent of disease. The disappointing experience with extended resections underscores the need for better adjuvant systemic strategies and the interdisciplinary care of patients with pancreatic adenocarcinoma.
Computer what?! Designing outreach activities to introduce computer science to K-12 in Qatar

Qatar is working towards becoming a knowledge-based society by 2030. However, there is a limited understanding of the field of computer science, especially at the K-12 level, as well as its potential impact to achieve the above goal. We have developed several outreach activities to help introduce K-12 students and their teachers to computer science through workshops on CS such as education, problem solving through puzzles, programming through Alice, robotics, and high school programming competitions. These initiatives have dramatically improved the understanding and acceptance of the field of computer science in Qatar in K-12 students, teachers, and administrators.
Pediatric Palliative Care and Inpatient Hospital Costs: A Longitudinal Cohort Study

BACKGROUND: Pediatric palliative care (PPC) improves the quality of life for children with life-limiting conditions, but the cost of care associated with PPC has not been quantified. This study examined the association between inpatient cost and receipt of PPC among high-cost inpatients. METHODS: The 10% most costly inpatients treated at a children’s hospital in 2010 were studied, and factors associated with receipt of PPC were determined. Among patients dying during 2010, we compared 2010 inpatient costs between PPC recipients and nonrecipients. Inpatient costs during the 2-year follow up period between PPC recipients and nonrecipients were also compared. Patients were analyzed in 2 groups: those who died and those who survived the 2-year follow-up. RESULTS: Of 902 patients, 86 (10%) received PPC. Technology dependence, older age, multiple chronic conditions, PICU admission, and death in 2010 were independently associated with receipt of PPC. PPC recipients had increased inpatient costs compared with nonrecipients during 2010. Among patients who died during the 2-year follow-up, PPC recipients had significantly lower inpatient costs. Among survivors, PPC recipients had greater inpatient costs. When controlling for patient complexity, differences in inpatient costs were not significant. CONCLUSIONS: The relationship of PPC to inpatient costs is complex. PPC seems to lower costs among patients approaching death. Patients selectively referred to PPC who survive most often do so with chronic serious illnesses that predispose them to remain lifelong high-resource utilizers.
The Great shift: the rise of Mexico and the Decline of Peru in the Spanish American Colonial Empire, 1680-1809

espanolA partir de la reconstruccion de las cuentas de la Real Tesoreria para las tres principales colonias de Hispanoamerica desde el ultimo cuarto del siglo XVII a la primera decada del siglo XIX, este ensayo reconstruye el destino cambiante de los ingresos y gastos reales en estas cruciales economias americanas. Los vicerreinatos de Peru y Mexico y la Audiencia de Charcos fueron las principales fuentes del superavit en las colonias americanas. Hasta 1700, las dos regiones andinas dominaron el sistema colonial hispanoamericano en terminos de ingresos reales generados y de plata producida, para ser exportada a Europa. Sin embargo, estas regiones comenzaron a declinar en el siglo XVIII. Los diferentes tipos de ingresos y gastos reales y su evolucion son analizados para cada una de estas tres colonias a fin de determinar sus tendencias a largo plazo y su importancia relativa. EnglishUsing the reconstructed royal treasury records for the trhee principal colonies of Spanish America from the last quarter of the 17th century to the first decade of the 19th century this essay constructs the changin fortunes of royal income and expenditures in these crucial American economies. The viceroyalties of Peru and Mexico an the Audiencia of Charcas were the principal sources of surplus revenues in the American colonies. Until 1700 the two Andean regions dominated the Spanish American colonial system in terms of generating royal income and in producing silver for export to Europe. But these soon declined relative to Mexico wich in the 18th century became to dominant economy and major source of royal income. The various royal revenues and expenditures and their performance over time are analyzed for all trhee colonies to determine the long term trends in dieir growth and relative importance.
Quindi - A code to simulate coherent emission from bending systems

We present a newly developed code, QUINDI, to address the numerical challenge of calculating the radiation spectra from electron bunches in bending magnet systems. This code provides a better tool for designing diagnostic systems such as bunch length monitors in magnetic chicanes. The program calculates emission on a first principle basis, combining the dominant emission processes in a bending magnet system - edge and synchrotron radiation. The core algorithm is based on the Lienard-Wiechert potential and utilizes parallel computer architecture to cover complete electron beam distributions with a high resolution spatial grid. The program models the coherence level of the emitted radiation from the electron bunch, focusing on long frequency components.
Technical Studies-Early Use of Metals

Excavated metals, some with secure dates as early as the eighth millennium BC, have been analyzed using a variety of scientific methods in order to provide insight into early metallurgical technology. The results are often used to reconstruct the role of technology in the social structure of the community. This lecture will review many of these methods giving examples from the examination of excavated objects.
Effect of Relative Humidity on Survival of Candida albicans and Other Yeasts

Individual blastospores of Candida albicans were deposited on the surface of 50-mm membranes (Millipore Corp.) and placed within sealed glass chambers at various relative humidities (RH). After 48 hr, virtually all cells maintained at 100 and 10% RH had survived, but 84% of the cells maintained at 60% RH failed to develop into colonies when transferred to Sabouraud medium. No morphological abnormalities could be observed in cells surviving low RH values, but their initial rate of multiplication after transfer to Sabouraud medium was greatly reduced, compared to that demonstrated by cells maintained at 100% RH. At 60% RH, the exposure time required to kill 50% of the blastospores was 2 to 3.5 days. The inimical effect of 60% RH was confirmed in a total of 21 isolates of C. albicans. No deleterious effect was noted when 12 other species of yeasts were subjected to 10, 60, and 100% RH. The single isolate of Candida brumptii and 1 out of the 20 isolates of Cryptococcus neoformans tested also failed to grow after blastospores had been exposed to 60% RH for 4 days.
The HARPSS process for fabrication of precision MEMS inertial sensors

Abstract The high aspect-ratio combined poly- and single-crystal silicon micromachining technology (HARPSS) and its application to fabrication of precision MEMS inertial sensors are presented. HARPSS is a single wafer, all silicon, front-side release process which is capable of producing 10–100's of microns thick, electrically isolated, 3-D poly- and single-crystalline silicon microstructures with various size air-gaps ranging from sub-micron to tens of microns. High aspect-ratio (>50:1) polysilicon structures are created by refilling 100's of microns deep trenches with polysilicon deposited over a sacrificial oxide layer. This technology provides features required for precision micromachined inertial sensors. The all-silicon feature of this technology improves long term stability and temperature sensitivity while fabrication of large area, vertical electrodes with sub-micron gap spacing will increase the sensitivity by orders of magnitude.