cssi/SciSciGPT-SciSciNet huggingface dataset:
Yula, Yucatan, Mexico

A major impediment to understanding the Terminal Classic to Early Postclassic transition in northern Yucatan has been the lack of a reliable ceramic chronology defined from stratigraphic contexts at the site of Chichen Itza. The temporal relationship of Cehpech and Soluta ceramics is central to resolving the issue of the correct chronological placement of Chichen Itza. The results of stratigraphic excavations at Yula, a small site 5 km south of Chichen Itza, provide the strongest evidence to date that Cehpech and Sotuta ceramics were contemporaneous. Statistical analysis of pottery composition by stratum confirms a positive correlation between Sotuta and Cehpech, which are clearly differentiated from earlier pottery. Rather than following a linear sequence in which Cehpech precedes Sotuta, as suggested by R. E. Smith and other early researchers, these two slatewares represent coeval regional variation. Thus, the major occupation of Chichen Itza dates not to the Early Postclassic, but to the Terminal Classic. The results of this research contribute toward the redefinition of the Terminal Classic and Early Postclassic periods in the northern Maya lowlands.
Micelles-mediated synthesis of magnetic Fe3Pt nanoparticles of cubic morphology and their characterisation

Abstract Development of a new synthetic route for the evolution of Fe3Pt particles with cubic morphology has been discussed here. These particles are expected to be applied for hyperthermia therapy due to their soft magnetic character because of a sharp fall of magnetic moment in the neighbourhood of 320 K. The soft magnetic property is due to their isotropic cubic morphology and structure.
Synchronization of coupled optomechanical oscillators

We demonstrate experimentally the synchronization of two micromechanical oscillators actuated by the optical radiation field. The mutual coupling is purely optical and fully tunable. Upon synchronization, the phase noise drops in agreement with the prediction.
Insulin degradation XXV. Glutathione-insulin transhydrogenase activity of rat liver and kidney during the development of stretptozotocin-diabetes

Abstract The activity of glutathione-insulin transhydrogenase (glutathione:protein-disulfide oxidoreductase, EC 1.8.4.2) in the liver and kidneys of rats during the development of streptozotocin-induced diabetes has been studied. Following a single injection of streptozotocin, the transhydrogenase activity fell rapidly for 7–8 days and then gradually with time in both organs. In contrast to the control rats where approximately 25% of the enzyme is in a ‘latent’ state, nearly all the transhydrogenase activity in the diabetic liver appears to be in the free or functional form. The results are consistent with the hypothesis that both hepatic andrenal glutathione-insuline transhydrogenase activity are under feedback control by circulating insulin. The possibility is discussed that the latent state may represent a storage form of the enzyme, which in insulin-insufficiency states is mobilized to the free or functional form for cell function.
An analysis of heat-, momentum-transports, and spectra for clear air turbulence in mid-stratosphere

An analysis of the clear air turbulence in the mid-stratosphere indicates that the turbulence is characterized by an anisotropic field of turbulence with an intense lateral component of the turbulence, associated with strong thermally stable stratification. The Richardson number in the region of turbulence is generally smaller than\(\frac{1}{4}\), the Taylor's criterion for a stratified shear flow.
Maneuvering and control of flexible space robots

This paper is concerned with a flexible space robot capable of maneuvering payloads. The robot is assumed to consist of two hinge-connected flexible arms and a rigid end-effector holding a payload; the robot is mounted on a rigid platform floating in space. The equations of motion are nonlinear and of high order. Based on the assumption that the maneuvering motions are one order of magnitude larger than the elastic vibrations, a perturbation approach permits design of controls for the two types of motion separately. The rigid-body maneuvering is carried out open loop, but the elastic motions are controlled closed loop, by means of discrete-time linear quadratic regulator theory with prescribed degree of stability. A numerical example demonstrates the approach. In the example, the controls derived by the perturbation approach are applied to the original nonlinear system and errors are found to be relatively small.
Geographic variation of reproductive tactics in lubber grasshoppers

We investigate plastic and interpopulation variation of trade-offs among reproductive tactics. There is a potential three-way trade-off among timing of reproduction, somatic storage, and investment in reproduction. We tested whether this trade-off shows latitudinal interpopulation variation. We studied populations of the lubber grasshopper, Romalea microptera, from Florida (FL; lowest latitude), Louisiana (LA; intermediate latitude), and Georgia (GA; highest latitude), each tested at three diet levels. All three populations differed in their multivariate responses of the three reproductive tactics we studied. This difference across populations was due primarily to age at first reproduction, secondarily to somatic storage, and less so to clutch mass. Age at first reproduction was least in GA, intermediate in LA, and greatest in FL grasshoppers. Somatic storage was greatest in FL and LA, and least in GA grasshoppers. Clutch mass was greatest in LA and GA, and least in FL grasshoppers. Diet levels also differed in this suite of reproductive tactics, primarily due to variation in age at reproduction. In contrast to significant, independent effects of population and diet, we find no evidence that the trade-off itself varies across populations (as indicated by the non-significant interaction of population and diet level). Thus, we show that the innate allocation of resources among reproductive tactics is different across populations, but all three populations responded similarly to a range of diet levels.
The social implications of the use of computers across national boundaries

Large time sharing systems and distributed networks of computers are already major factors in tying together decentralized national operations in both the public and the private sectors. In the public sector, the marriage of computers and communications is apparent in such systems as the ARPA Network, the Air Defense System, law enforcement systems, weather forecasting and the like. In the private sector, there are many such systems used for tying together sales offices and warehouses or ticket offices and data banks of reservations systems, as well as serving various other scheduling, financial control or logistics operations in large corporations. In fact, discussions on the design and development of massive national or regional information utilities have been appearing with increasing frequency of late.
Combining estimators to improve structural model estimation and inference under quadratic loss

Asymptotically, semi parametric estimators of the parameters in linear structural models have the same sampling properties. In finite samples the sampling properties of these estimators vary and large biases may result for sample sizes often found in practice. With a goal of improving asymptotic risk performance and finite sample efficiency properties, we investigate the idea of combining correlated structural equation estimators with different finite and asymptotic sampling characteristics. Based on a quadratic loss measure, we present evidence that the finite sample performance of the resulting combination estimator can be notably superior to that of a leading traditional moment based estimator.
Random walks on lattices. IV. Continuous-time walks and influence of absorbing boundaries

The general study of random walks on a lattice is developed further with emphasis on continuous-time walks with an asymmetric bias. Continuous time walks are characterized by random pauses between jumps, with a common pausing time distributionψ(t). An analytic solution in the form of an inverse Laplace transform for P(l, t), the probability of a walker being atl at timet if it started atlo att=0, is obtained in the presence of completely absorbing boundaries. Numerical results for P(l, t) are presented for characteristically different ψ(t), including one which leads to a non-Gaussian behavior for P(l, t) even for larget. Asymptotic results are obtained for the number of surviving walkers and the mean 〈l〉 showing the effect of the absorption at the boundary.
Molecular Order in High-Efficiency Polymer/Fullerene Bulk Heterojunction Solar Cells

We report quantitative measurements of ordering, molecular orientation, and nanoscale morphology in the active layer of bulk heterojunction (BHJ) organic photovoltaic cells based on a thieno[3,4-b]thiophene-alt-benzodithiophene copolymer (PTB7), which has been shown to yield very high power conversion efficiency when blended with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM). A surprisingly low degree of order was found in the polymer—far lower in the bulk heterojunction than in pure PTB7. X-ray diffraction data yielded a nearly full orientation distribution for the polymer π-stacking direction within well-ordered regions, revealing a moderate preference for π-stacking in the vertical direction (“face-on”). By combining molecular orientation information from polarizing absorption spectroscopies with the orientation distribution of ordered material from diffraction, we propose a model describing the PTB7 molecular orientation distribution (ordered and disordered), with the fraction of ordered polymer...
Helminths of Tropidurus guarani (Sauria: Tropiduridae) from Paraguay

Abstract Seventy-seven of 81 (95%) Tropidurus guarani collected in Ybycui National Park, Paraguay were found to harbor 1 or more of 7 helminth species: Oochoristica bresslaui, Parapharyngodon scleratus, Piratuba digiticaudata, Physaloptera lutzi, Spauligodon oxkutzcabiensis, Strongyluris oscari, and Skrjabinelazia intermedia. All represent new host and new locality records.
Prediction of Pairwise Gene Interaction Using Threshold Logic

The two important problems of computational biology are the modeling of gene regulatory networks and the study of the network structure of complex biological systems. There is an increased use of mathematical and computational theory techniques to solve both these problems. The Boolean circuit model is one of the most popular modeling paradigms used to model gene regulatory networks. In this paper we try to make use of the properties of threshold logic (an alternative to Boolean logic to design digital circuits) to determine the network structure of gene systems. This approach uses the gene-expression data from microarray experiments as input. The proposed method was first used to build the gene network for a set of genes, proteins, and other molecular components based on in silico data. Then, the method was applied to a biological dataset to build the gene regulatory network for a core set of genes associated with melanoma. Some of the interactions found could be verified by earlier biological experiments reported in published literature. Other interactions that could not be validated by existing biological knowledge can provide insights into the investigation of bio-chemical pathways associated with melanoma development.
Techniques of Interviewing: Setting up an Interviewing Course

In this article the logistics utilized in conveying a specific type of interviewing technique to students, previously reported on, are outlined. Specifically described is an introductory course that has been effective in communicating interview techniques to groups of students working closely with a perceptor by alternating demonstration and didactic instruction with trial and error exercises. Since psychiatrists are increasingly used in teaching and directing interviewing courses in medical schools, it is suggested that they be intimately involved in planning these programs.
The Effects of High Salinity, Water-Deficit, and Abscisic Acid on Phosphoeno/pyruvate Carboxylase Activity and Proline Accumulation in Mesembryanthemum crystallinum Cell Cultures

Summary It has been established from previous studies in the halophyte Mesembryanthemum crystallinum that saline conditions induce the synthesis of phospho enol pyruvate carboxylase (PEPC), the performance of Crassulacean acid metabolism (CAM), and the production of compatible solutes such as proline. The objective of the present study was to determine whether factors causing the induction of these processes in leaves were also effective in tissue cultures of M. crystallinum grown under different conditions. In heterotrophically (sucrose)-grown calli of M. crystallinum , low levels of NaCl (10 to 25 mM) were required for optimum growth, while increasing concentrations of salt up to 200 mM caused a progressive decline in growth. Addition of salt to the culture medium caused a progressive increase in proline accumulation (13 fold increase in calli grown in 200 mM NaCl compared with calli grown without salt) but had little affect on PEPC activity in calli grown in sucrose media in the dark or light. Addition of 10 -7 M abscisic acid in the presence of 200 mM NaCl doubled the proline content in light-grown calli, while abscisic acid alone had no affect. However, growth with 10 -7 to 10 -5 M abscisic acid had no affect on levels of PEPC in dark or light-grown calli, in contrast to the previously reported induction of this enzyme and CAM by provision of abscisic acid to whole plants. Water stress (imposed by addition of polyethylene glycol) and low levels of NaCl (10 mM) in combination caused a large increase in proline content in heterotrophically cultured cells, whereas neither were effective alone. In photomixotrophic cell cultures, obtained by replacement of sucrose by soluble starch as the external carbon supply, there was a much higher chlorophyll content, and a limited salt induced increase in PEPC activity (4 fold enhancement during a 12-d, 200-mM, salt-shock period).
The Software Life Cycle Processes standard

A new standard, Software Life Cycle Processes (ISO/IEC 12207), developed over the past six years, has recently been approved by JTC1 (Joint Technical Committee 1 of the International Organization for Standardization and the International Electrotechnical Commission). While software has been established as an integral part of scientific and business disciplines, environments for developing and managing software have proliferated without a common, uniform framework for the software life cycle. This standard provides such a framework, so that software practitioners can speak the same language when they create and manage software. Practitioners can use the framework to acquire, supply, develop, operate, and maintain software. >
Analysis of cracks at deep notches

Abstract This paper describes the fatigue behavior of cracks located at two deep “dovetail” notch geometries. Fadgue tests with transparent polymer models produced changes in crack size and shape as a function of elapsed cycles. Numerical stress intensity factor solutions were determined for both through-cracks (using a finite element code), and corner cracks (using a boundary element code) located at the notch bore. The numerical stress intensity factor solutions were verified by predicting fatigue lives, crack sizes and shapes for the experimental results. These predictions showed that the numerically determined stress intensity factors accurately predict fatigue lives, as well as crack size and shape for the dovetail geometries.
Importance of soil moisture and its interaction with competition and clipping for two montane meadow grasses

Meadow classification studies have demonstrated the importance of water table fluctuation patterns in determining plant community composition in the western United States. However, a mechanism causing an overall increase in Poa pratensis ssp. pratensis populations and local declines in Deschampsia cespitosa populations in western montane meadows over the past century has not been defined. In order to better understand plant species interactions in these often highly grazed systems, we observed aboveground responses of Poa and Deschampsia to changes in species composition, soil moisture gradients, and clipping in the field. As well, we conducted a factorial greenhouse experiment, varying plant density, water availability, and clipping. While Poa is adapted to dry meadows and Deschampsia to wet meadows, their ranges overlap in wet conditions where soil moisture averages 50% in the early growing season. Deschampsia appears to be excluded from dry meadows where Poa is prevalent and soil moisture is closer to 30% water content in the early growing season. Our greenhouse experiment revealed that Deschampsia’s competitive ability decreases, while Poa’s increases, at soil moistures of 19%. However in more mesic conditions (50% soil moisture), each species aboveground biomass, tillering, and inflorescence weight was adherent to soil moisture conditions, and species interactions were less important. Our early growing season clipping treatments significantly reduced biomass of both grasses, but did not appear to favor one species over the other. This work points to the importance of soil water content in determining the performance of each plant species and the level of species interactions in montane meadows.
Parallel solid-phase synthesis of 2-arylamino-6H-pyrano[2,3-f]benzimidazole-6-ones

The parallel solid-phase synthesis of a hydrophilic psoralen analogue, 2-arylamino-6H-pyrano[2,3-f]benzimidazole-6-ones (2-arylaminoimidazocoumarins), has been developed. The resin-bound 7-fluoro-4-methyl-6-nitro-2-oxo-2H-1-benzopyran-3-carboxylic acid underwent aromatic substitution with primary amines, followed by reduction of the nitro group with tin(II) chloride. The cyclization of the o-dianilino intermediates was accomplished with aryl isothiocyanates in the presence of 1,3-diisopropylcarbodiimide (DIC). The final products were released from the resin with trifluoroacetic acid (TFA) and obtained in high purity and good isolated yield. The 2-arylaminoimidazocoumarins exhibit interesting spectral properties.
Unusual Properties of Accessory Pathways

Electrophysiologic evaluation in five patients who exhibited manifestations of the pre-excitation syndrome and/or supraventricular tachycardia provided functional evidence that the properties of the accessory fibers may be quite variable. The unusual responses to electrical stimulation in these patients included: 1) failure to depolarize the His bundle from the site of ventricular pre-excitation; 2) supraventricular tachycardia with two types of re-entry; 3) anterograde block in the accessory pathway with intact retrograde conduction; and 4) retrograde delay or block in the accessory pathway and atrioventricular (A-V) node with intact anterograde conduction. Understanding these variations may provide important therapeutic implications regarding drug and surgical management. In addition to these anomalies in conduction over accessory pathways we demonstrated in these patients the occurrence of retrograde functional right bundle branch block and retrograde "gap" phenomenon, and ventricular reciprocation wit...
Dissecting Single-Molecule Signal Transduction in Carbon Nanotube Circuits with Protein Engineering

Single-molecule experimental methods have provided new insights into biomolecular function, dynamic disorder, and transient states that are all invisible to conventional measurements. A novel, nonfluorescent single-molecule technique involves attaching single molecules to single-walled carbon nanotube field-effective transistors (SWNT FETs). These ultrasensitive electronic devices provide long-duration, label-free monitoring of biomolecules and their dynamic motions. However, generalization of the SWNT FET technique first requires design rules that can predict the success and applicability of these devices. Here, we report on the transduction mechanism linking enzymatic processivity to electrical signal generation by a SWNT FET. The interaction between SWNT FETs and the enzyme lysozyme was systematically dissected using eight different lysozyme variants synthesized by protein engineering. The data prove that effective signal generation can be accomplished using a single charged amino acid, when appropriately located, providing a foundation to widely apply SWNT FET sensitivity to other biomolecular systems.
Combinatorial immunoglobulin libraries on the surface of phage (Phabs): Rapid selection of antigen-specific fabs

Here we describe a revolutionary method for the rapid selection of monoclonal antibodies. A phagemid system for the monovalent display of combinatorial Fab libraries on the surface of filamentous phage M13 was developed. Phage displaying Fab fragments on their surface (Phabs) were enriched on antigencoated surfaces 10 3 - to 10 5 -fold over nonspecific phage. This method provides the most expeditious route to monoclonal antibodies yet described.
Multiple Bile Duct Hamartomas Mimicking Diffuse Hepatic Metastasis: GI Image

Bile duct hamartomas (von Meyenburg complex) are the rare benign neoplasm of the liver due to dysembryogenesis; constituted historically, cystic dilatations of the bile duct encompassed by fibrous stroma. Usually, they are asymptomatic and are not detected on routine radiological examinations including ultrasound or CT scan. Magnetic resonance cholangiography has been suggested as the best investigation for their imaging diagnosis. Their presence can cause diagnostics confusion and complicate the patient’s management. We report a 45-year-old female with symptomatic cholelithiasis, whose liver on laparoscopy mimicked multiple hepatic metastases.
Osteosarcoma in Paget's Disease of Bone

Paget's disease of bone (PDB) is a focal disorder of bone metabolism first described by Sir James Paget in 1876. It is presumed benign in nature and mediated by abnormal osteoclast function. The incidence of osteosarcomas complicating PDB is estimated at <1%. These cancers occur mostly in persons with long-standing, polyostotic disease and affect patients in their seventh decade or when osteosarcoma is remarkably rare in the general population. Epidemiological studies suggest that this late peak of osteosarcomas is absent in regions where Paget's is infrequently reported. Whereas PDB has a predilection for the axial skeleton, skull, femurs, and tibias, pagetic osteosarcoma tend to spare the spine, and are reported more commonly in the pelvis, femur, humerus, and skull. A molecular basis for the association of osteosarcoma with Paget's disease is unclear. These osteosarcomas are osteogenic in origin, consistently arise in sites of pagetic bone, and may present as metachronous, multifocal lesions. On histopathology, the lesions are usually osteoblastic, and the tumor phenotype is sometimes characterized as an exaggerated, chaotic form of the accelerated bone remodeling that characterizes PDB. New insights from the biology of adolescent osteosarcomas, VCP and SQSTM1 mutations now defined in patients with Paget's disease, and emerging evidence that stromal lesions are present in patients with Paget's disease are changing the way we think about the pathogenesis of PDB and the rare complication of pagetic osteosarcomas.
Energy requirements, interactions and distinctions in the mechanisms for transport of various nucleosides in Escherichia coli

Abstract The transport of cytidine and uridine in Escherichia coli, like that of adenosine, is sensitive to energy poisons and apparently can be coupled to energy metabolism. The depletion of energy reserves, however, does not prevent the passive uptake of cytidine which indicates that an active pumping mechanism is not an essential or obligatory component of the transport process. This finding, together with similar results previously reported for adenosine and β-galactoside transport, suggests that energy coupling to non-electrolyte transport generally may be facultative in E. coli. Adenosine, cytidine and uridine strongly compete with one another for entry. However, the three transport sites are not identical since each site shows a different sensitivity to the action of thiol reagents and exposure to high temperatures. Cytidine transport sites are only partially destroyed by treatment with large concentrations of N- ethylmaleimide , suggesting that more than one kind of site mediates the entry of this nucleoside. The sensitive portion has a reactivity to N- ethylmaleimide comparable to those sites for adenosine and uridine. Both adenosine and uridine inhibit cytidine transport with competitive kinetics in untreated cells. In cells in which the transport sites of the competing nucleosides have been abolished by treatment with thiol reagents together with heat, cytidine transport is still inhibited. Possible mechanisms to explain these interactions are discussed.
Arbitrarily Oriented Cracks in a Reinforced Sheet

The elastic interaction between a crack and a fiber is studied for various loading conditions. Generalized from earlier work by Greif and Sanders, the present formulation is valid for arbitrary relative orientation between the crack and the fiber. Helpful design information, such as the critical loading condition and the critical fiber orientation to trigger a certain failure mode, is therefore attainable. The fundamental solutions, each associated with proper parameters and proper boundary conditions, can also be superposed to model more realistic problems.
Access control by testing for shared knowledge

Controlling the privacy of online content is difficult and often confusing. We present a social access control where users devise simple questions testing shared knowledge instead of constructing authenticated accounts and explicit access control rules. We implemented a prototype and conducted studies to explore the context of photo sharing security, gauge the difficulty of creating shared knowledge questions, measure their resilience to adversarial attack, and evaluate user ability to understand and predict this resilience.
A class of rational systems for modelling 1/f power spectra [of biological signals]

A class of rational systems for modelling the power spectra of 1/f signals are introduced. This class is characterized by the cascade of frequency scaled versions of an arbitrary prototype rational function which has the same number of zeros and poles. The novelty of the approach lies in the fact that the scale-invariant nature of the power-law response is intentionally imposed on the rational system via the frequency scaling operation, resulting in /spl gamma/-homogeneous rational functions. For finite bandwidth systems, as the number of elements in the cascade increases, the deviations from exact 1/f behavior decrease so that arbitrarily good approximations to an exact power-law behavior can be achieved. The rational models previously derived using other approaches can be shown to be special cases of the class of rational models introduced here. While these results have been presented in the context of the rational modelling of 1/f power spectra, the solution can be used to achieve a power-law magnitude response where the scaling exponent /spl lambda/ satisfies -/spl infin/ >
Effect of ionic impurities on the electric field alignment of diblock copolymer thin films

In Forschung hast Du immer zu mir gesagt, “Schaffe etwas!”. Mein Chef, ich habe immer versucht Deinen Befehlen zu folgen. Ich widme Dir diese Veroffentlichung. Mensch, mit funf und siebzig bist Du noch jung, schon Geburtstag! The effect of ionic impurities on the electric field alignment of lamellar microdomains in polystyrene-block-poly(methyl methacrylate) diblock copolymer thin films was studied using transmission electron microscopy (TEM) and atomic force microscopy (AFM). At lithium ion concentrations greater than ~210 ppm, the microdomain morphology in block copolymers could be aligned in the direction of an applied electric field, regardless of the strength of interfacial interactions. Complete alignment of the copolymer microdomains, even those adjacent to the polymer/substrate interface, occurred by a pathway where the applied electric field enhanced fluctuations at the interfaces of the microdomains with a wavelength comparable to L o, the equilibrium period of the copolymer. This enhancement in the fluctuations led to a disruption of the lamellar microdomains into smaller microdomains ~L o in size, that, in time, reconnected to form microdomains oriented in the direction of the applied field.
Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

The hydroperoxy radical (HO2) plays a critical role in Earth's atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work, we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on the order of 108 molecules·cm-3 at 298 K, that the number of HO2···H2O complexes is on the order of 107 molecules·cm-3 and the number of HO2···(H2O)2 complexes is on the order of 106 molecules·cm-3. Using the computed abundance of HO2···H2O, we predict that, at 298 K, the bimolecular rate constant for HO2···H2O + HO2 is about 10 times that for HO2 + HO2.
Review of Recent Developments in Fire Detection Technologies

Progress in fire detection technologies has been substantial over the last decade due to advances in sensor, microelectronics and information technologies, as well as a greater understanding of fire physics. This paper provides a review of progress in fire detection technologies over the last decade, including various emerging sensor technologies (e.g., computer vision system, distributed fiber optic temperature sensor, and intelligent multiple sensor), signal processing and monitoring technology (e.g., real-time control via Internet) and integrated fire detection systems. Some problems and future research efforts related to current fire detection technologies are discussed.
REMOVAL OF A VISCOUS FILM FROM A RIGID PLANE SURFACE BY AN IMPINGING LIQUID JET

A thin uniform film of viscous liquid, that initially covers a plane rigid surface is removed under the shearing action of an impinging jet of water. Data are presented for the mean thickness of residual film as a function of time, over a wide range of jet and film parameters. A simple theoretical model, based on existing studies of the shear stress exerted by a jet on a rigid surface, and using the Reynolds lubrication approximation in the film, is in excellent agreement with the data.
The Indefinite Logarithm, Logarithmic Units, and the Nature of Entropy

We define the indefinite logarithm [log x] of a real number x > 0 to be a mathematical object representing the abstract concept of the logarithm of x with an indeterminate base (i.e., not specifically e, 10, 2, or any fixed number). The resulting indefinite logarithmic quantities naturally play a mathematical role that is closely analogous to that of dimensional physical quantities (such as length) in that, although these quantities have no definite interpretation as ordinary numbers, nevertheless the ratio of two of these entities is naturally well-defined as a specific, ordinary number, just like the ratio of two lengths. As a result, indefinite logarithm objects can serve as the basis for logarithmic spaces, which are natural systems of logarithmic units suitable for measuring any quantity defined on a logarithmic scale. We illustrate how logarithmic units provide a convenient language for explaining the complete conceptual unification of the disparate systems of units that are presently used for a variety of quantities that are conventionally considered distinct, such as, in particular, physical entropy and information-theoretic entropy.
Environmental Reviews and Case Studies: The Road to Zero Waste: A Study of the Seattle Green Fee on Disposable Bags

Waste reduction is a policy objective being pursued around the world, and many jurisdictions are now considering bag fees as a targeted way to deal with an avoidable waste stream. Seattle City Government passed legislation in July 2008 that placed a $0.20 fee on paper or plastic bags given at the checkout stand of grocery stores, convenience stores, and drugstores. However, an opposition campaign collected enough signatures to send the measure to a public vote in August 2009, where it was turned down. Understanding the lessons learned from this and previous bag-fee legislation will be useful to interested governments. Governments must understand that disposable bags symbolize convenience to many, and many citizens are unaware of the true consequences of handling waste. I conclude that for this breed of policy to be successful, four components are necessary: public education on the issue and the environmental context of the policy; a provision to mitigate financial hardship that may arise from the fee on l...
Perceptions of beer foam.

Consumers do differentiate between beers on the basis of their foam properties. The appearance of a stable foam on beer does influence consumer's preconceptions about the flavour of that beer. Consumers differ in the criteria they apply to judge foam quality: some prefer a stable head of moderate depth which leaves no residue after drinking; others find foam lacing to be appealing.
Socially Optimized Learning in a Virtual Environment: Reducing Risky Sexual Behavior Among Men Who Have Sex With Men

A socially optimized learning approach, which integrates diverse theoretical perspectives, places men who have sex with men (MSM) in an interactive virtual environment designed to simulate the emotional, interpersonal, and contextual narrative of an actual sexual encounter while challenging and changing MSM’s more automatic patterns of risky responses. MSM assume a character’s identity and are scaffolded in their decision-making and relearning process by supportive, and often humorous, peer coaches who encourage situated learning of self-regulatory and behavioral skills, and tailor and frame their responses to be responsive to the men’s behavioral choices. In a longitudinal design, participants were randomly assigned to receive either an interactive video (IAV) intervention with peer counseling or to a peer-counseling-alone control. Compared to the counseling alone, men who also received the IAV reduced risky anal sex behaviors and increased protected anal sex behaviors.
Closing the divide: Diverse populations and cancer survivorship†

Currently, there is a "divide" between cancer survivorship initiatives and minority participation. The level of participation is nearly nonexistent in many cancer support and control initiatives. Cancer survivorship resources that facilitate access to treatment, psychosocial interventions, clinical trials, and research are key components to eliminating this divide. Differences in cancer results among minority populations are caused by several factors, including biologic reactions to environmental activities, socioeconomic status, perceived beliefs and notions of medical professionals, a lack of resources to participate in cancer support groups, and having personal contact with cancer survivors. Health professionals, advocates, and researchers hold the key to opening more opportunities for the improvement of cancer survivorship among minorities. The belief that "one size fits all" is unrealistic. These beliefs can influence participation in innovative clinical trials, decisions about treatment, emotional responses, and social support relationships. To help ensure participation in these programs, researchers and health workers must understand the role of social and psychosocial implications and results of the assessment, strategies, and sustainability that must be included in the development stage of any cancer support and survivorship initiatives. For this article, the authors examined mechanisms that can be used by cancer-control researchers and program staff to limit the divide between cancer survivorship initiatives and minority participation. They identified three strategies that must be used to address this divide effectively: the inclusion of minorities in clinical trials, intervention studies, treatment, and research programs; the development of culturally sensitive environments; and the ability to sustain minority participation. In summary, cancer survivorship includes many components that are developed individually and collectively to formulate sound strategies for including minorities in cancer-control initiatives. These programs should go beyond basic support groups and should include research studies, clinical trials, and alternative treatments for increasing cancer survival rates and quality of life among minorities. The divide can be addressed only through a proactive initiative that brings cancer survivorship initiatives and minority communities together in full partnership.
Role of the endocannabinoid system in learning and memory

Following the discovery of an endocannabinoid system in the central nervous system, which consists of the endogenous ligands arachidonoylethanolamide (anandamide) and the monoacylglycerol 2-arachidonoyl glycerol (2-AG) that bind to the CB1 receptor [1, 2], a great deal of effort has been focused on understanding the physiological function of this system. The identification of these and other putative endogenous cannabinoids, including noladin ether [3] and virodhamin [4], has sparked further in understanding the physiological functions of the endogenous cannabinoid system. A growing body of evidence suggests that this system serves several physiological functions including the modulation of pain [5–7], feeding [8], drug dependence [9–11], excitotoxicity [12], and cognition [13, 14]. In this review, we discuss recent in vivo and in vitro research investigating the role that the endocannabinoid system plays in learning and memory. Recent behavioral evidence indicates that the endocannabinoid system modulates key components of learning and memory, which include memory consolidation and extinction. On the molecular level, endocannabinoids have been demonstrated to modulate electrophysiological correlates of learning, suggesting that they play an important role in synaptic plasticity. Investigations into the role of the endocannabinoid system in learning processes should make important advances in the following three areas: (1) development of new cannabinoid-based pharmacotherapies with minimal undesirable side effects, (2) understanding the long-term consequences of marijuana use (which remains the most commonly used illicit drug [15]), and (3) shedding light on basic issues in neuroscience such as how are memories formed, stored, and forgotten?
Warpage studies of HDI test vehicles during various thermal profilings

New techniques and technologies involved in the miniaturization of printed wiring board (PWB) fabrication are rapidly emerging. The quality, performance, and reliability of surface mount assemblies built on these next-generation boards will depend on many factors, including thermally induced warpage. Therefore, quantitative warpage measurement is critical in new PWB assembly design evaluation, and determining overall thermal performance characteristics. Using an automated infrared reflow oven simulation system, the warpage of six bare high density interconnect (HDI) samples is measured under two different heating profiles. Out-of-plane surface displacement is measured with a noncontact shadow Moire technique and resolution enhancement method called phase-stepping. The two types of samples evaluated were built for the purpose of warpage study, where physical data could be used to validate finite element analysis (FEA) results. The warpage results obtained with the two thermal profiles will be presented.
A National Study of Outcomes among HIV-Infected Kidney Transplant Recipients

Kidney transplantation is a viable treatment for select patients with HIV and ESRD, but data are lacking regarding long-term outcomes and comparisons with appropriately matched HIV-negative patients. We analyzed data from the Scientific Registry of Transplant Recipients (SRTR; 2002–2011): 510 adult kidney transplant recipients with HIV (median follow-up, 3.8 years) matched 1:10 to HIV-negative controls. Compared with HIV-negative controls, HIV-infected recipients had significantly lower 5-year (75.3% versus 69.2%) and 10-year (54.4% versus 49.8%) post-transplant graft survival (GS) (hazard ratio [HR], 1.37; 95% confidence interval [95% CI], 1.15 to 1.64; P P =0.005). However, compared with HIV-negative/hepatitis C virus (HCV)–negative controls, HIV monoinfected recipients had similar 5-year and 10-year GS, whereas HIV/HCV coinfected recipients had worse GS (5-year: 64.0% versus 52.0%, P =0.02; 10-year: 36.2% versus 27.0%, P =0.004 [HR, 1.38; 95% CI, 1.08 to 1.77; P =0.01]). Patient survival (PS) among HIV-infected recipients was 83.5% at 5 years and 51.6% at 10 years and was significantly lower than PS among HIV-negative controls (HR, 1.34; 95% CI, 1.08 to 1.68; P P =0.007; 10-year: 29.3% versus 56.23%, P =0.002 [HR, 1.57; 95% CI, 1.11 to 2.22; P =0.01]). In conclusion, HIV-negative and HIV monoinfected kidney transplant recipients had similar GS and PS, whereas HIV/HCV coinfected recipients had worse outcomes. Although encouraging, these results suggest caution in transplanting coinfected patients.
Using Program Families for Maintenance Experiments

In general, new modularization techniques require a significant intellectual investment from practitioners in order to adopt them. Before practitioners are willing to make such an investment, they want a careful scientific assessment of the technique for a number of properties (e.g., effects on reusability, reliability, and maintainability). Our work is concerned with conducting such empirical investigations for assessing how modularization techniques affect maintainability; in particular, this paper presents an approach to conducting formal experiments for assessing a technique's impact on perfective maintenance. We refer to such experiments as maintenance experiments in the sequel. We are currently using our program families-based approach in maintenance experiments to assess a technique we previously invented for modularizing synchronization concerns, called Szumo. The root program of each family implements a multi-threaded GUI browser, which reads and displays text from a network server. We are using three perfective maintenance tasks to populate the program families: one that adds network error handling, another that adds more settings and GUI controls, and another that reads data from multiple servers.
A 10GHz nonlinear cosine-weighted digital-to-analog converter for high-speed direct digital synthesis

A SiGe cosine-weighted digital-to-analog converter (DAC) with 10 GHz sampling rate is presented. The nonlinear DAC is used in a direct digital synthesis (DDS) to replace the conventional look up table and the linear DAC. It takes the advantage of high switching speed of SiGe current switches and uses the current mode logic (CML) circuits to realize the digital control logic. The DAC is designed using a 47 GHz SiGe technology and achieves a maximum 5 GHz output frequency with 10 GHz clock.
The Deer Hunter: The Unintended Effects of Hunting Regulations ∗

Abstract To control the deer population, state game commissions regulate the types of deer that can be legally harvested. These regulations, however, might have an unintended effect on hunting-related accidents by changing the care hunters take when firing their rifles—a moral hazard effect—or changing the composition of hunters. Using detailed data on hunting accidents and regulations in Pennsylvania counties from 1990 to 2005, we find compelling evidence that harvesting restrictions increase the care hunters take in a manner consistent with moral hazard. Thus, these regulations have a positive safety externality.
Why Egalitarianism Might Be Good for Your Health: Physiological Thriving During Stressful Intergroup Encounters

We compared how evaluations by out-group members and evaluations by in-group members affected participants' stress responses--their neuroendocrine reactivity, cognitive appraisals, and observed anxiety--and how participants' implicit racial bias moderated these responses. Specifically, White participants completed measures of racial bias prior to the experiment. During the experiment, participants performed speech and serial subtraction tasks in front of White or Black interviewers. Several saliva samples were obtained, and they were assayed for catabolic ("breaking down") and anabolic ("building up") hormones. Interviewers' race and participants' racial bias interacted in predicting stress responses. When interviewers were Black, lower racial bias was linked with more salutary stress responses: lower threat appraisals, less anxiety, and increased levels of anabolic hormones. When interviewers were White, no effect was found for threat appraisals or anabolic hormones, and the reverse effect was observed for anxiety. Egalitarianism may have physical and psychological benefits for people living in a diverse society.
CoBaFi: collaborative bayesian filtering

Given a large dataset of users' ratings of movies, what is the best model to accurately predict which movies a person will like? And how can we prevent spammers from tricking our algorithms into suggesting a bad movie? Is it possible to infer structure between movies simultaneously? In this paper we describe a unified Bayesian approach to Collaborative Filtering that accomplishes all of these goals. It models the discrete structure of ratings and is flexible to the often non-Gaussian shape of the distribution. Additionally, our method finds a co-clustering of the users and items, which improves the model's accuracy and makes the model robust to fraud. We offer three main contributions: (1) We provide a novel model and Gibbs sampling algorithm that accurately models the quirks of real world ratings, such as convex ratings distributions. (2) We provide proof of our model's robustness to spam and anomalous behavior. (3) We use several real world datasets to demonstrate the model's effectiveness in accurately predicting user's ratings, avoiding prediction skew in the face of injected spam, and finding interesting patterns in real world ratings data.