cssi/SciSciGPT-SciSciNet huggingface dataset:
Decision tree ensemble machine learning for rapid QSTS simulations

High-resolution, quasi-static time series (QSTS) simulations are essential for modeling modern distribution systems with high-penetration of distributed energy resources (DER) in order to accurately simulate the time-dependent aspects of the system. Presently, QSTS simulations are too computationally intensive for widespread industry adoption. This paper proposes to simulate a portion of the year with QSTS and to use decision tree machine learning methods, random forests and boosting ensembles, to predict the voltage regulator tap changes for the remainder of the year, accurately reproducing the results of the time-consuming, brute-force, yearlong QSTS simulation. This research uses decision tree ensemble machine learning, applied for the first time to QSTS simulations, to produce high-accuracy QSTS results, up to 4x times faster than traditional methods.
Baryon and Lepton Non-Conservation, Majorana Neutrinos and Neutron ( N \leftrightarrow \bar N ) Oscillations

Baryon and lepton number violating processes are discussed as a tool to study the existence of intermediate mass scales below 1015 GeV. We emphasize that particularly interesting in this connection are ΔB = 2 processes that cause \( N \leftrightarrow \bar N \) oscillations and N1 + N2 → pions. Detailed phenomenology of \( N \leftrightarrow \bar N \) oscillation is presented. A partial unification model where B- and L- breakdown arises from spontaneous breakdown is reviewed and its implications are presented. Implications of grand unified models based on SU(5) and SO(10) for such processes are noted.
The Jónsson Class of Ordered Sets

This is the principal example of a Jonsson class. Arguments such as the back-and-forth induction of Cantor and Hausdorff occur here in their initial and prototypical form (Theorem 5.3). There is also a useful analogy between the simple arguments concerning the η α -property of ordered sets and the more technically detailed arguments involving the (H α ) and (R α ) properties of Boolean algebras studied in §6 below; in this sense the material of the present section is preparatory to § 6.
Weight loss, wasting, and survival in HIV-positive patients: current strategies.

Wasting syndrome has been a common HIV-related condition reported in the United States. Three analyses from the Tufts Nutrition for Healthy Living study shed new light on the syndrome. Analysis of Cox proportional hazards models showed that losses in weight, fat-free mass, body cell mass, and fat mass, both from baseline weight and from weight at previous follow-up, were all significant indicators of mortality in patients with the HIV wasting syndrome. In the second analysis, the prevalence of 5% weight loss from the previous visit was shown to be 35% greater in the late HAART era, from 1998 to 2003, than in the early HAART era of 1995 to 1997 (P < .02). This corresponds with earlier observations that the diagnosis of HIV wasting had been increasing during the decade of the 1990s. In the third analysis, the researchers found that body weight, fat-free mass, and body mass index improved in patients receiving nutritional intervention compared with patients receiving placebo.
East European Discontent: Economic Attitudes across Class, Ethnicity, and Time

Rise of populist and right-wing tendencies in Eastern Europe has been linked to people’s increasing dissatisfaction with the economy and growing inequality. Using Life in Transition Survey, we exam...
Teaching Organizational Behavior: The Experiential Approach

(2003). Teaching Organizational Behavior: The Experiential Approach. Journal of Public Affairs Education: Vol. 9, No. 1, pp. 87-91.
Prevention and Management of Hepatitis B in Healthcare Professionals

To review the epidemiology of hepatitis B virus (HBV) transmission in the healthcare setting and outline best practices in the prevention and management of chronic HBV in healthcare professionals. Hepatitis B virus (HBV) infection remains a global public health burden and chronically infects an estimated 257 million persons worldwide. HBV represents one of the most important occupational risks for healthcare workers (HCWs) due to efficient transmission through percutaneous exposure of HBV-infected blood and blood-contaminated body fluids. Although the incidence of HCW-patient transmission of HBV has decreased significantly since 2000, ongoing deficits in HCW testing, vaccination, and confirmation of immunity, as well as post-exposure management protocols, raise concern for ongoing risk for nosocomial exposure. Established recommendations of the AASLD, CDC, and SHEA provide guidance to clinicians on the prevention and management of chronic HBV in healthcare professionals.
EMMA: Hardware/Software Attestation Framework for Embedded Systems Using Electromagnetic Signals

Establishing trust for an execution environment is an important problem, and practical solutions for it rely on attestation, where an untrusted system (prover) computes a response to a challenge sent by the trusted system (verifier). The response typically is a checksum of the prover's program, which the verifier checks against expected values for a "clean" (trustworthy) system. The main challenge in attestation is that, in addition to checking the response, the verifier also needs to verify the integrity of the response computation. On higher-end processors, this integrity is verified cryptographically, using dedicated trusted hardware. On embedded systems, however, constraints prevent the use of such hardware support. Instead, a popular approach is to use the request-to-response time as a way to establish confidence. However, the overall request-to-response time provides only one coarse-grained measurement from which the integrity of the attestation is to be inferred, and even that is noisy because it includes the network latency and/or variations due to micro-architectural events. Thus, the attestation is vulnerable to attacks where the adversary has tampered with response computation, but the resulting additional computation time is small relative to the overall request-to-response time. In this paper, we make a key observation that execution-time measurement is only one example of using externally measurable side-channel information, and that other side-channels, some of which can provide much finer-grain information about the computation, can be used. As a proof of concept, we propose EMMA, a novel method for attestation that leverages electromagnetic side-channel signals that are emanated by the system during response computation, to confirm that the device has, upon receiving the challenge, actually computed the response using the valid program code for that computation. This new approach requires physical proximity, but imposes no overhead to the system, and provides accurate monitoring during the attestation. We implement EMMA on a popular embedded system, Arduino UNO, and evaluate our system with a wide range of attacks on attestation integrity. Our results show that EMMA can successfully detect these attacks with high accuracy. We compare our method with the existing methods and show how EMMA outperforms them in terms of security guarantees, scalability, and robustness.
Laboratory-Scale Evaluation of the Effects of Water-Filled Pore Space on Emissions of CO2, CH4, N2O, and N2 from Soil-Based Wastewater Treatment

Microbial removal of C and N in soil-based wastewater treatment involves emission of CO2, CH4, N2O, and N2 to the atmosphere. Water-filled pore space (WFPS) can exert an important control on microbial production and consumption of these gases. We examined the impact of WFPS on emissions of CO2, CH4, N2O, and N2 in soil microcosms receiving septic tank effluent (STE) or effluent from a single-pass sand filter (SFE), with deionized-distilled (DW) water as a control. Incubation of B and C horizon soil for 1 h (the residence time of wastewater in 1 cm of soil) with DW produced the lowest greenhouse gas (GHG) emissions, which varied little with WFPS. In B and C horizon soil amended with SFE emissions of N2O increased linearly with increasing WFPS. Emissions of CO2 from soil amended with STE peaked at WFPS of 0.5–0.8, depending on the soil horizon, whereas in soil amended with SFE, the CO2 flux was detectable only in B horizon soil, where it increased with increasing WFPS. Methane emissions were detectable only for STE, with flux increasing linearly with WFPS in C horizon soil, but no clear pattern was observed with WFPS for B horizon soil. Emissions of GHG from soil were not constrained by the lack of organic C availability in SFE, or by the absence of NO3 availability in STE, and addition of acetate or NO3 resulted in lower emissions in a number of instances. Emission of 15N2 and 15N2O from 15NH4 took place within an hour of contact with soil, and production of 15N2 was much higher than 15N2O. 15N2 emissions were greatest at the lowest WFPS value and diminished markedly as WFPS increased, regardless of water type and soil texture. Our results suggest that the fluxes of CO2, CH4, N2O, and N2 respond differently to WFPS, depending on water type and soil texture.
Synthesis and analysis of separation processes for extracellular chemicals generated from microbial conversions

Recent advances in metabolic engineering have enabled the production of chemicals via bio-conversion using microbes. However, downstream separation accounts for 60–80% of the total production cost in many cases. Previous work on microbial production of extracellular chemicals has been mainly restricted to microbiology, biochemistry, metabolomics, or techno-economic analysis for specific product examples such as succinic acid, xanthan gum, lycopene, etc. In these studies, microbial production and separation technologies were selected apriori without considering any competing alternatives. However, technology selection in downstream separation and purification processes can have a major impact on the overall costs, product recovery, and purity. To this end, we apply a superstructure optimization based framework that enables the identification of critical technologies and their associated parameters in the synthesis and analysis of separation processes for extracellular chemicals generated from microbial conversions. We divide extracellular chemicals into three categories based on their physical properties, such as water solubility, physical state, relative density, volatility, etc. We analyze three major extracellular product categories (insoluble light, insoluble heavy and soluble) in detail and provide suggestions for additional product categories through extension of our analysis framework. The proposed analysis and results provide significant insights for technology selection and enable streamlined decision making when faced with any microbial product that is released extracellularly. The parameter variability analysis for the product as well as the associated technologies and comparison with novel alternatives is a key feature which forms the basis for designing better bioseparation strategies that have potential for commercial scalability and can compete with traditional chemical production methods.
Security Certification in Payment Card Industry: Testbeds, Measurements, and Recommendations

The massive payment card industry (PCI) involves various entities such as merchants, issuer banks, acquirer banks, and card brands. Ensuring security for all entities that process payment card information is a challenging task. The PCI Security Standards Council requires all entities to be compliant with the PCI Data Security Standard (DSS), which specifies a series of security requirements. However, little is known regarding how well PCI DSS is enforced in practice. In this paper, we take a measurement approach to systematically evaluate the PCI DSS certification process for e-commerce websites. We develop an e-commerce web application testbed, BuggyCart, which can flexibly add or remove 35 PCI DSS related vulnerabilities. Then we use the testbed to examine the capability and limitations of PCI scanners and the rigor of the certification process. We find that there is an alarming gap between the security standard and its real-world enforcement. None of the 6 PCI scanners we tested are fully compliant with the PCI scanning guidelines, issuing certificates to merchants that still have major vulnerabilities. To further examine the compliance status of real-world e-commerce websites, we build a new lightweight scanning tool named PciCheckerLite and scan 1,203 e-commerce websites across various business sectors. The results confirm that 86% of the websites have at least one PCI DSS violation that should have disqualified them as non-compliant. Our in-depth accuracy analysis also shows that PciCheckerLite's output is more precise than w3af. We reached out to the PCI Security Council to share our research results to improve the enforcement in practice.
A solution to some grounding problems for relationism

Let wF, wC+, and wC− be three distinct worlds, each of which contains only a single point-sized material particle, and in each of which spacetime is: uniformly flat, constantly positively curved, a...
Multiscale modeling of epoxies and epoxy-based composites

Epoxies play an important role in determining the performance of epoxy-based composites, coatings, and adhesives. Multiscale modeling methods emerge as a complementary tool to conventional experimental and theoretical approaches and are widely used to study the relationships between processing, structure, and property of polymer materials. This paper aims to provide a review of multiscale modeling efforts on epoxy and epoxy-based materials with a main focus on DGEBA and DGEBF systems. Material’s structural, thermal, mechanical, and interfacial properties are discussed in details.
Why Do Firms Market Time Debt Maturity --- A Trade-Off Theory Based Explanation

Evidence shows that firms market time their debt maturity. Specifically, maturity is found to be inversely proportional to the term spread (the difference between long and short-term Treasury yield). That is, firms issue short-term debt when the term spread is large and they increase maturity as the term spread decreases. In this article, we build a model explaining the market timing phenomenon using the trade-off theory of capital structure. Our explanation relies on the balance between the bankruptcy cost and the debt issuance transaction cost. When the term spread is large, bankruptcy costs outweigh transaction costs. Firms reduce debt maturity as it lowers bankruptcy probability. In the same spirit, firms increase maturity to lower transaction cost when the term spread is small. With our model, we also link maturity with leverage, loss given default, and frequency of capital structure adjustment. Our result does not depend on the presence of either liquidity shocks or agency costs or imperfect information. Finally, we empirically corroborate our theory.
Occupational Outcomes and Return to Running After Operative Management of Lisfranc Injuries in a High-Demand Population:

Background: Literature evaluating outcomes following operative fixation of Lisfranc injuries has demonstrated high rates of chronic disability, particularly in those returning to prior levels of physical function. The purpose of this study is to evaluate the occupational outcomes and return to running after open reduction and internal fixation (ORIF) or arthrodesis for Lisfranc fracture-dislocations in a moderate- to high-demand military cohort. Methods: All active-duty servicemembers undergoing ORIF or primary arthrodesis (Current Procedural Terminology 28615 and 28730, respectively) for confirmed Lisfranc fracture-dislocations (International Classification of Diseases, Ninth Revision codes 838.03 or 838.13) with minimum 2-year follow-up were isolated from the Military Health System. Demographic and surgical variables were recorded. Return to military function, return to running, perioperative morbidity, and rates of reoperation for complication were the outcomes of interest. Univariate analysis followed by multivariate logistic regression determined the association between patient demographics, type of fracture fixation (ie, ORIF vs arthrodesis) and functional outcomes, including medical separation. Results: Among Lisfranc injuries, 64 patients underwent ORIF while 6 underwent primary arthrodeses with a mean age of 28.1 years. At mean follow-up of 3.5 years (range, 2.0-6.3 years), 20% of servicemembers underwent medical separation due to limitations related to their injuries. body mass index (BMI) ≥30 kg/m2 (OR 17.67; 95% CI, 3.69-84.53) and Army or Marines service branch (OR 3.86; 95% CI, 1.08-13.86) were significant independent predictors for medical separation. Among servicemembers undergoing ORIF or primary arthrodeses, 69% returned to occupationally required daily running during the follow-up period. Servicemembers with a BMI <30 kg/m2 were more likely to return to running (OR 13.14, 95% CI, 2.50-69.19). Radiographic evidence of posttraumatic Lisfranc osteoarthritis occurred in 10 (16%) servicemembers who underwent internal fixation, and 82% of ORIF patients underwent implant removal. Conclusions: At mean 3.5-year follow-up, 80% of servicemembers undergoing ORIF or primary arthrodeses for Lisfranc injuries remained on active duty or successfully completed their military service, and 69% were able to resume occupationally required daily running. Surgeons should preoperatively counsel patients with these injuries on the possibility of persistent long-term disability. Levels of Evidence: Level IV: Retrospective series.
Second Victim Support: Nurses' Perspectives of Organizational Support After an Adverse Event.

Objective The purpose of this study was to describe hospital nurses' experiences with organizational support after an adverse event (AE). Background Most hospital staff nurses will experience an AE, being left and feeling traumatized. Methods Data collection and analysis followed a qualitative descriptive approach. Results Nurses yearn to feel valued and to receive timely support from nurse executives after an AE. Conclusions To help lessen the suffering of the nurse after an AE, healthcare organizations and nurse executives must support the nurse in the aftermath.
Continued Dosing of Oritavancin for Complicated Gram-Positive Infections.

Several retrospective and cohort analyses have suggested that continued dosing of oritavancin is both safe and efficacious for complicated Gram-positive infections, such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.
The Use of Input Words Vectorsto Detect Crowd Region in Images

Human crowd analysis has common utilizations from the urban engineering and traffic management to law enforcement. They all need a crowd for first being detected, and is the issue that has been dealt with in the present study. Considering an image, the algorithm that has been proposed in this paper performs a segmentation of that image to crowd and non-crowd areas. The fundamental concept is capturing two main characteristics of the crowd: (a) on a narrower scale, its main elements have to appear like humans (only weakly so, as a result of the low resolution, dressing variations, occlusion, and so on), whereas (b) on the wider scale, the crowd intrinsically includes elements of the redundant appearance. The proposed approach makes use of that through the utilization of underlying statistical framework which has been based on the quantized features of the SURF. The two previously mentioned characteristics of the crowds have been obtained through the resultant statistical model responses’ feature vector, which describe the level of crowd-like appearances around the location of an image with the increase of the spatial level around it.
Introduction to Envisioning

This brief chapter introduces the first section of the book Socially Engaged Art History and Beyond: Alternative Approaches to the Theory and Practice of Art History, which is composed of four essays that describe both the conceptual and actual places in which socially engaged art history is emerging and growing. This introduction also addresses the use of terminology in the field.
Green nanomaterials: On track for a sustainable future

Summary Nanotechnology is one of the most significant scientific and industrial breakthroughs of the twenty-first century. With applications that cross scientific boundaries—from electronics to medicine, to advanced manufacturing, to cosmetics—nanotechnology has the potential to dramatically change lifestyles, jobs, and whole economies [1] . However, many of the materials and processes currently used not only are dependent on nonrenewable resources but also create hazardous wastes. The combination of green chemistry techniques with nanotechnology applications has thus become a key component of the nanotechnology future. The use of natural ingredients to synthesize nanomaterials and design environmentally benign synthetic processes has been extensively explored. While many of these so-called “green nanotechnologies” are now finding their way from the laboratory to commercial application, green nanotechnology still faces significant challenges. This article presents the recent advances and challenges in green nanotechnology, and suggests ways to improve the commercial readiness of these technologies.
Infinitary computability with infinite time turing machines

Recent developments in the theory of infinite time Turing machines include the solution of the infinitary P versus NP problem and the rise of infinitary computable model theory.
Treponemal Antibodies in Non-Syphilitic, Positive Anti-Nuclear Factor Sera

An inherent problem to the valid use of the standard FTA-200 test as a laboratory adjunct for the diagnosis of syphilis is the capacity of certain sera to react with the antigen (s) common to both pathogenic and saprophytic treponemal strains. Deacon (1) investigated 4 treponemal strains including Treponema pallidum and the Reiter's treponeme and found a common antigen to all. Reactivity to the common antigen has been regarded as non-specific for syphilis, and Hunter et al. (2) proposed a solution to the problem which entailed selective combination of the antibody to the common fraction with a liquid Reiter's treponemal sonicate. Thus, emerged the FT A absorbed test (FTA-ABS)* which was highly selective for the Nicholas strain antigen (s) without sacrificing sensitivity. Because the Reiter's sonicate antigen as an absorbing agent has not been completely evaluated and is not yet available commercially, many laboratories are still performing the FTA-200 test (3). This report deals with certain conditions which cause the FTA-200 procedure to become moderate or strongly reactive, and which, though non-specific for syphilis, have valuable clinical significance; and if not properly understood, may be mistaken as due to syphilitic infection.
Homage to an Itinerant Master

MathematicsSAN DIEGO —The mathematics community paid tribute at a meeting here last month to one of its legendary figures: Paul Erdos, who died last September. Erdos is considered the most prolific mathematician ever, yet he had no permanent home and no formal job after 1954—only a vast succession of collaborators and a gift for problems that opened productive new areas of research.
Protecting Mobile Agents Against Malicious Hosts

A key element of any mobile code based distributed system are the security mechanisms available to protect (a) the host against potentially hostile actions of a code fragment under execution and (b) the mobile code against tampering attempts by the executing host. Many techniques for the first problem (a) have been developed. The second problem (b) seems to be much harder: It is the general belief that computation privacy for mobile code cannot be provided without tamper resistant hardware. Furthermore it is doubted that an agent can keep a secret (e.g., a secret key to generate digital signatures). There is an error in reasoning in the arguments supporting these beliefs which we are going to point out. In this paper we describe software-only approaches for providing computation privacy for mobile code in the important case that the mobile code fragment computes an algebraic circuit (a polynomial). We further describe an approach how a mobile agent can digitally sign his output securely.
Multi-Agent Research in the Knobotics Group

This is a short overview of research in multi-agent systems within our research group at Stanford University, knobotics. We discuss research that centers around the formal ascription of mental attitudes to computational entities, the framework of agent oriented programming (AOP), and distributed coordination mechanisms.
Concurrent optimization of process dependent variations in different circuit performance measures

A method for multi-objective circuit variability optimization in the presence of process variations is presented. Critical process parameter variations are identified by determining their correlations to the circuit performance measures of interest. Then, the distributions of these critical process parameters are used to identify the critical designable parameters for variability optimization. Membership functions and fuzzy set intersection operators are used to transform multiple design objectives into a single objective function suitable for optimization. Afterwards, the objective function for variability is minimized. Finally, the mean circuit performance measures are fine tuned for given target specifications.
Separate Branches of the uvr Gene-Dependent Excision Repair Process in Ultraviolet-Irradiated Escherichia coli K-12 Cells; Their Dependence upon Growth Medium and the polA, recA, recB, and exrA Genes

The extent of repair of single-strand breaks (incision breaks) induced in the deoxyribonucleic acid (DNA) of Escherichia coli K-12 cells by the uvr gene-dependent excision repair process after ultraviolet (UV) radiation was determined in the wild-type, polA1, recA56, recB21, and exrA strains. The wild-type strain repaired all incision breaks after incident doses of UV radiation (254 nm) of approximately 60 J m(-2) or less when incubated in growth medium, or approximately 15 J m(-2) or less when incubated in buffer. The polA1 strain repaired the incision breaks completely after incident doses of approximately 12 J m(-2) or less when incubated in growth medium, or after approximately 4 J m(-2) when incubated in buffer. The recA13, recB21, and exrA strains showed essentially complete repair after incident doses of 10 to 15 J m(-2) whether the cells were incubated in buffer or growth medium. These results suggest that the uvr gene-dependent excision repair process may be divided into two branches, one which is dependent on the presence of growth medium and also the rec(+)exr(+) genotype, and a second which can occur in buffer (growth medium-independent) and is largely dependent on DNA polymerase I. The presence of chloramphenicol in the growth medium resulted in an inhibition of the growth medium-dependent repair occurring in wild-type and polA1 cells and had little or no effect on the extent of repair observed in recA56, recB21, or exrA cells. The similarities between the growth medium-dependent and -independent branches of excision repair and two known processes for the repair of X-ray-induced single-strand breaks are discussed.
mTORC2 Deficiency in Myeloid Dendritic Cells Enhances Their Allogeneic Th1 and Th17 Stimulatory Ability after TLR4 Ligation In Vitro and In Vivo

The mammalian/mechanistic target of rapamycin (mTOR) is a key integrative kinase that functions in two independent complexes, mTOR complex (mTORC) 1 and mTORC2. In contrast to the well-defined role of mTORC1 in dendritic cells (DC), little is known about the function of mTORC2. In this study, to our knowledge, we demonstrate for the first time an enhanced ability of mTORC2-deficient myeloid DC to stimulate and polarize allogeneic T cells. We show that activated bone marrow-derived DC from conditional Rictor(-/-) mice exhibit lower coinhibitory B7-H1 molecule expression independently of the stimulus and enhanced IL-6, TNF-α, IL-12p70, and IL-23 production following TLR4 ligation. Accordingly, TLR4-activated Rictor(-/-) DC display augmented allogeneic T cell stimulatory ability, expanding IFN-γ(+) and IL-17(+), but not IL-10(+) or CD4(+)Foxp3(+) regulatory T cells in vitro. A similar DC profile was obtained by stimulating Dectin-1 (C-type lectin family member) on Rictor(-/-) DC. Using novel CD11c-specific Rictor(-/-) mice, we confirm the alloreactive Th1 and Th17 cell-polarizing ability of endogenous mTORC2-deficient DC after TLR4 ligation in vivo. Furthermore, we demonstrate that proinflammatory cytokines produced by Rictor(-/-) DC after LPS stimulation are key in promoting Th1/Th17 responses. These data establish that mTORC2 activity restrains conventional DC proinflammatory capacity and their ability to polarize T cells following TLR and non-TLR stimulation. Our findings provide new insight into the role of mTORC2 in regulating DC function and may have implications for emerging therapeutic strategies that target mTOR in cancer, infectious diseases, and transplantation.
Navigation Results from Desert Field Tests of the Rocky 7 Mars Rover Prototype

Upcoming missions to the surface of Mars will use mobile robots to traverse long distances from the landing site. To prepare enabling technologies for these missions, the protype rover, Rocky 7, has been tested in desert field trials conducted with a team of planetary scientists.
Analysis of protein binding to receptor-doped lipid monolayers by Monte Carlo simulation

This paper presents a Monte Carlo simulation (MCS) method for estimating the parameters that characterize ligand-receptor binding directly from experimentally derived binding isotherms. Binding parameters are estimated by incorporating an MCS algorithm for ligand binding to a two-dimensional receptor array into a nonlinear regression program. The MCS method was tested by analyzing experimental isotherms of avidin binding to biotinylated lipid in Langmuir-Blodgett (LB) monolayers. The MCS-derived cooperativity coefficients and intrinsic association constants for avidin-biotin binding to LB films are correlated strongly (R2 > 0.93) with the binding parameters determined from the same experimental data by a thermodynamic equilibrium binding model (Zhao et al. 1993. Langmuir. 9:3166–3173). This result shows MCS to be an accurate and potentially more versatile method for characterizing biomolecular interactions at surfaces.
Probabilistic Mesomechanical Fatigue Crack Nucleation Model

A probabilistic mesomechanical crack nucleation model is proposed to link the microstructural material heterogeneities to the statistical scatter in the macrostructural response. The macrostructure is modeled as an ensemble of microelements. Cracks nucleate within the microelements and grow from the microelements to final fracture. Variations of the microelement properties are defined using statistical parameters. A micromechanical slip band decohesion model along with a Paris law crack growth model are used with first order reliability methods and Monte Carlo simulation to determine the distribution of fatigue life for the macrostructure. The modeled response is compared to trends in experimental observations from the literature.
3D plane-wave migration in tilted coordinates: A field data example

We have extended isotropic plane-wave migration in tilted coordinates to 3D anisotropic media and applied it on a Gulf of Mexico data set. Recorded surface data are transformed to plane-wave data by slant-stack processing in inline and crossline directions. The source plane wave and its corresponding slant-stacked data are extrapolated into the subsurface within a tilted coordinate system whose direction depends on the propagation direction of the plane wave. Images are generated by crosscorrelating these two wavefields. The shot sampling is sparse in the crossline direction, and the source generated by slant stacking is not really a plane-wave source but a phase-encoded source. We have discovered that phase-encoded source migration in tilted coordinates can image steep reflectors, using 2D synthetic data set examples. The field data example shows that 3D plane-wave migration in tilted coordinates can image steeply dipping salt flanks and faults, even though the one-way wave-equation operator is used for wavefield extrapolation.
How is the Ideal Gas Law Explanatory

Using the ideal gas law as a comparative example, this essay reviews contemporary research in philosophy of science concerning scientific explanation. It outlines the inferential, causal, unification, and erotetic conceptions of explanation and discusses an alternative project, the functional perspective. In each case, the aim is to highlight insights from these investigations that are salient for pedagogical concerns. Perhaps most importantly, this essay argues that science teachers should be mindful of the normative and prescriptive components of explanatory discourse both in the classroom and in science more generally. Giving attention to this dimension of explanation not only will do justice to the nature of explanatory activity in science but also will support the development of robust reasoning skills in science students while helping them understand an important respect in which science is more than a straightforward collection of empirical facts, and consequently, science education involves more than simply learning them.
Hydrodynamic coefficients of a monolithic circular offshore structure

Expressions for both the rectilinear and rotational inertial and damping coefficients for a circular monolithic tower of uniform radius are derived. The analysis matches the fluid velocity, derived from potential theory, with the structural velocity in sway. That is, the motions of the tower are assumed to be in a vertical plane. The analysis is then applied to a tower composed of (lumped-mass) elements, where the expressions for the added-mass and damping coefficients are shown to be functions of wave number. The added-mass is shown to be a product of two wave systems: a travelling wave system, which is responsible for the radiation damping, and a standing wave system, called the evanescent system, which is attached to the structure. The added-mass of the evanescent system is negative for small wave numbers, while that of the travelling waves is positive. The negative sign simply means that the inertial force of the evanescent waves is 180° out of phase with that of the travelling system. Furthermore, it is shown that the contributions of the two wave systems to the total added-mass of the structure counteract each other, resulting in a total added-mass which varies gradually with the wave number. Finally, the analysis is applied to an experiment, and results of the analysis and the experiment are found to agree rather well.
Pathophysiology of nonneoplastic obstruction of the foramen of Monro and progressive unilateral hydrocephalus

Our experience with progressive unilateral hydrocephalus in children and the pathophysiology of nonneoplastic obstruction of the foramen of Monro has been analyzed. The status of the foramen of Monro in either congenital or acquired progressive unilateral hydrocephalus was classified into the following four categories: Category 1, atresia of the foramen; Category 2, morphological obstruction; Category 3, functional obstruction; and Category 4, patent foramen. Illustrative cases including hydrodynamic studies and intracranial pressure monitoring are discussed.
Sodium intake and mortality in the NHANES II follow-up study.

Abstract Purpose US Dietary Guidelines recommend a daily sodium intake Methods Observational cohort study linking sodium, estimated by single 24-hour dietary recall and adjusted for calorie intake, in a community sample (n = 7154) representing 78.9 million non-institutionalized US adults (ages 30-74). Hazard ratios (HR) for CVD and all-cause mortality were calculated from multivariable adjusted Cox models accounting for the sampling design. Results Over mean 13.7 (range: 0.5-16.8) years follow-up, there were 1343 deaths (541 CVD). Sodium (adjusted for calories) and sodium/calorie ratio as continuous variables had independent inverse associations with CVD mortality ( P = .03 and P = .008, respectively). Adjusted HR of CVD mortality for sodium P = .033), and 1.28 (95% CI: 1.10-1.50, P = .003) for all-cause mortality. Alternate sodium thresholds from 1900-2700 mg gave similar results. Results were consistent in the majority of subgroups examined, but no such associations were observed for those Conclusion The inverse association of sodium to CVD mortality seen here raises questions regarding the likelihood of a survival advantage accompanying a lower sodium diet. These findings highlight the need for further study of the relation of dietary sodium to mortality outcomes.
Mouse Naïve CD4+ T Cell Isolation and In vitro Differentiation into T Cell Subsets

Antigen inexperienced (naive) CD4(+) T cells undergo expansion and differentiation to effector subsets at the time of T cell receptor (TCR) recognition of cognate antigen presented on MHC class II. The cytokine signals present in the environment at the time of TCR activation are a major factor in determining the effector fate of a naive CD4(+) T cell. Although the cytokine environment during naive T cell activation may be complex and involve both redundant and opposing signals in vivo, the addition of various cytokine combinations during naive CD4(+) T cell activation in vitro can readily promote the establishment of effector T helper lineages with hallmark cytokine and transcription factor expression. Such differentiation experiments are commonly used as a first step for the evaluation of targets believed to promote or inhibit the development of certain CD4(+) T helper subsets. The addition of mediators, such as signaling agonists, antagonists, or other cytokines, during the differentiation process can also be used to study the influence of a particular target on T cell differentiation. Here, we describe a basic protocol for the isolation of naive T cells from mouse and the subsequent steps necessary for polarizing naive cells to various T helper effector lineages in vitro.
In Vitro Analysis of Nanoparticulate Hydroxyapatite/Chitosan Composites as Potential Drug Delivery Platforms for the Sustained Release of Antibiotics in the Treatment of Osteomyelitis

Nanoparticulate composites of hydroxyapatite (HAp) and chitosan were synthesized by ultrasound-assisted sequential precipitation and characterized for their microstructure at the atomic scale, surface charge, drug release properties, and combined antibacterial and osteogenic response. Crystallinity of HAp nanoparticles was reduced because of the interference of the surface layers of chitosan with the dissolution/reprecipitation-mediated recrystallization mechanism that conditions the transition from the as-precipitated amorphous calcium phosphate phase to the most thermodynamically stable one--HAp. Embedment of 5-10 nm sized, narrowly dispersed HAp nanoparticles within the polymeric matrix mitigated the burst release of the small molecule model drug, fluorescein, bound to HAp by physisorption, and promoted sustained-release kinetics throughout the 3 weeks of release time. The addition of chitosan to the particulate drug carrier formulation, however, reduced the antibacterial efficacy against S aureus. Excellent cell spreading and proliferation of osteoblastic MC3T3-E1 cells evidenced on microscopic conglomerates of HAp nanoparticles in vitro also markedly diminished on HAp/chitosan composites. Mitochondrial dehydrogenase activity exhibited normal values only for HAp/chitosan particle concentrations of up to 2 mg/cm(2) and significantly dropped, by about 50%, at higher particle concentrations (4 and 8 mg/cm(2)). The gene expression of osteocalcin, a mineralization inductor, and the transcription factor Runx2 was downregulated in cells incubated in the presence of 3 mg/cm(2) HAp/chitosan composite particles, whereas the expression of osteopontin, a potent mineralization inhibitor, was upregulated, further demonstrating the partially unfavorable osteoblastic cell response to the given particles. The peak in the expression of osteogenic markers paralleling the osteoblastic differentiation was also delayed most for the cell population incubated with HAp/chitosan particles. Overall, the positive effect of chitosan coating on the drug elution profile of HAp nanoparticles as carriers for the controlled delivery of antibiotics in the treatment of osteomyelitis was compensated for by the lower bacteriostatic efficiency and the comparatively unviable cell response to the composite material, especially at higher dosages.
The acute effects of low flow oxygen and isosorbide dinitrate on left and right ventricular ejection fractions in chronic obstructive pulmonary disease

The objectives of this study were to determine the effects of low flow oxygen and isosorbide dinitrate on rest and exercise biventricular ejection fractions in patients with chronic obstructive pulmonary disease and to relate these ejection fraction responses to changes in pressure and flow. Nine patients with stable, moderate to severe chronic obstructive pulmonary disease who had no prior history of heart failure performed supine exercise with simultaneous hemodynamic and radionuclide ventriculographic monitoring. Eight patients performed a second exercise during low flow oxygen breathing and five performed a third exercise after ingesting 10 mg oral isosorbide. Oxygen led to a decrease in exercise pulmonary artery pressure in all subjects and a decline in total pulmonary resistance in five of the seven in whom it was measured. Right ventricular ejection fraction increased 0.05 or more only in subjects who had a decrease in total pulmonary resistance. Isosorbide led to an increase in rest and exercise right and left ventricular ejection fractions with simultaneous decreases in pulmonary artery pressure, total pulmonary resistance, blood pressure and arterial oxygen tension. These results suggest that in patients with chronic obstructive pulmonary disease but without a history of right heart failure, the right ventricular systolic functional response to low flow oxygen and isosorbide at rest and exercise is, in part, determined by changes in total pulmonary resistance. The chronic relation between right ventricular ejection fraction and pulmonary hemodynamics in patients with chronic obstructive pulmonary disease remains to be evaluated.
Personnel accounting timeliness: An HPI case study from the U.S. Navy

The U.S. Navy must account for the whereabouts of 350, 000 sailors, so maintaining accurate personnel accounting records is critical. However, personnel records are not always updated in a timely fashion. The human performance improvement model was applied to the timeliness of personnel transactions performance gap, with encouraging results.
100 Nanometer Scale Resistive Heater-Thermometer on a Silicon Cantilever

This paper reports a method to fabricate a 100 nm scale heater-thermometer into a silicon microcantilever based on contact photolithography and a controlled annealing process. The heater is formed during a photolithography process that can achieve a minimum feature size of about 1 ?m, while careful control of doping and annealing parameters allows the heater size to be further decreased, to a width of 100 nm. The heater is fabricated onto the free end of a silicon cantilever suitable for scanning probe microscopy, and can be integrated into cantilevers with or without sharp tips. The fabricated heater has a maximum temperature of over 700°C, and a heating time of 56 ?sec to reach 500°C.
893 MORPHOLOGY, DEVELOPMENT AND DISTRIBUTION OF HUMAN NK CELLS IDENTIFIED BY A MONOCLONAL ANTIBODY (HNK-1)

A monoclonal IgM antibody (HNK-1) has been shown to react with a subset of human lymphocytes that can function as natural killer (NK) and antibody dependent killer (K) cells. HNK-1 antigen is present on 60% of Tγ cells (Fcγ receptor+, E-rosette+) and 56% of “null” cells (FcγR+ER−sIg-) but not on sIg-bearing B cells and monocytes. In the present studies we have used immunofluorescent and cell sorter techniques to examine the development, distribution, morphology and function of cells expressing HNK-1. Fewer than 1% of cells in thymus and newborn blood samples were HNK-1+. The number of circulating HNK-1+ cells increased as a function of age: 40 years of age. HNK-1+ cells comprised a mean of 12% of spleen cells but <1% of lymph node cells. The level of NK and K cell functions was closely related with the numbers of HNK-1+ cells in all tissues examined. Morphologically, HNK-1+ cells were defined as a homogeneous population of lymphocytes with abundant cytoplasm containing azurophilic granules. A significant proportion of HNK-1+ cells coexpressed antigens previously defined by monoclonal antibodies on T cells and monocytes. Our studies define a morphologically distinct subpopulation of lymphocytes of unknown origin with NK and K activities, the HNK-1+ cells were shown to expand as a function of age and exhibit selective migration. NIH CA 16673 and CA 27197.
Using afterimages for orientation and color to explore mechanisms of visual filling-in.

Simulations of Grossberg’s FACADE model of visual perception have previously been used to explain afterimage percepts produced by viewing a sequence of orthogonally oriented gratings. Additional simulations of the model are now used to predict new afterimage percepts. One simulation emphasizes that the afterimage percepts are the result of orientation afterresponses and color afterresponses that interact at a filling-in stage. We report experimental data that agree with FACADE’s prediction. A second simulation emphasizes the properties of the model’s filling-in stage and predicts a situation where the afterimage percept should not appear. We report experimental data indicating that this model prediction is incorrect. We argue that the model is unable to account for this result unless the filling-in stage mechanisms are different from a diffusive-type process. We propose an alternative mechanism, and simulations demonstrate the system’s ability to account for the afterimage data.
Bank liquidity preference and the investment demand constraint

Abstract Aggregate bank liquidity preference is postulated to engender an investment demand constraint. This idea is integrated into a stochastic dynamic structural macroeconomic model to study output and inflation fluctuations. The model has two regimes that allows for examining output and inflation adjustments over time given a change in commercial bank mark-up lending rate, quantitative easing and stochastic output shocks. The two financial regimes are: (i) an investment demand constraint regime; and (ii) a bank liquidity trap regime. The time adjustment of output and inflation given a change in mark-up lending rate and monetary easing depends on the financial regime in which the economy finds itself. Adjustments owing to stochastic output shocks do not depend on the financial regime. The nature of the regime is determined by the level of the mark-up lending rate and its strength of adjustment over time relative to the competitive loanable funds rate.