cssi/SciSciGPT-SciSciNet huggingface dataset:
Macross: Urban Dynamics Modeling based on Metapath Guided Cross-Modal Embedding.

As the ongoing rapid urbanization takes place with an ever-increasing speed, fully modeling urban dynamics becomes more and more challenging, but also a necessity for socioeconomic development. It is challenging because human activities and constructions are ubiquitous; urban landscape and life content change anywhere and anytime. It's crucial due to the fact that only up-to-date urban dynamics can enable governors to optimize their city planning strategy and help individuals organize their daily lives in a more efficient way. Previous geographic topic model based methods attempt to solve this problem but suffer from high computational cost and memory consumption, limiting their scalability to city level applications. Also, strong prior assumptions make such models fail to capture certain patterns by nature. To bridge the gap, we propose Macross, a metapath guided embedding approach to jointly model location, time and text information. Given a dataset of geo-tagged social media posts, we extract and aggregate location and time and construct a heterogeneous information network using the aggregated space and time. Metapath2vec based approach is used to construct vector representations for times, locations and frequent words such that co-occurrence pairs of nodes are closer in latent space. The vector representations will be used to infer related time, locations or keywords for a user query. Experiments done on enormous datasets show our model can generate comparable if not better quality query results compared to state of the art models and outperform some cutting-edge models for activity recovery and classification.
Distinct seasonal climate drivers revealed in a network of tree-ring records from Labrador, Canada

Traditionally, high-latitude dendroclimatic studies have focused on measurements of total ring width (RW), with the maximum density of the latewood (MXD) serving as a complementary variable. Whilst MXD has typically improved the strength of the growing season climate connection over that of RW, its measurements are costly and time-consuming. Recently, a less costly and more time-efficient technique to extract density measurements has emerged, based on lignin’s propensity to absorb blue light. This Blue Intensity (BI) methodology is based on image analyses of finely-sanded core samples, and the relative ease with which density measurements can be extracted allows for significant increases in spatio-temporal sample depth. While some studies have attempted to combine RW and MXD as predictors for summer temperature reconstructions, here we evaluate a systematic comparison of the climate signal for RW and latewood BI (LWBI) separately, using a recently updated and expanded tree ring database for Labrador, Canada. We demonstrate that while RW responds primarily to climatic drivers earlier in the growing season (January–April), LWBI is more responsive to climate conditions during late spring and summer (May–August). Furthermore, RW appears to be driven primarily by large-scale atmospheric dynamics associated with the Pacific North American pattern, whilst LWBI is more closely associated with local climate conditions, themselves linked to the behaviour of the Atlantic Multidecadal Oscillation. Lastly, we demonstrate that anomalously wide or narrow growth rings consistently respond to the same climate drivers as average growth years, whereas the sensitivity of LWBI to extreme climate conditions appears to be enhanced.
The properties of the [Mn12O12(O2CR)16(H2O)4] single-molecule magnets in truly axial symmetry: [Mn12O12(O2CCH2Br)16(H2O)4].4CH2Cl2

Detailed studies are reported of a Mn(12) single-molecule magnet (SMM) in truly axial (tetragonal) symmetry. The complex is [Mn(12)O(12)(O(2)CCH(2)Br)(16)(H(2)O)(4)].4CH(2)Cl(2) (2.4CH(2)Cl(2) or Mn(12)-BrAc), obtained by the standard carboxylate substitution method. The complex has an S = 10 ground state, typical of the Mn(12) family, and displays frequency-dependent out-of-phase AC susceptibility signals and hysteresis in single-crystal magnetization vs applied DC field sweeps. Single-crystal high-frequency EPR spectra in frequencies up to 360 GHz exhibit narrow signals that are not overlapping multiplets, in contrast to [Mn(12)O(12)(O(2)CMe)(16)(H(2)O)(4)].2MeCO(2)H.4H(2)O (1 or Mn(12)-Ac), which also crystallizes in an axial (tetragonal) space group but which now is recognized to consist of a mixture of six hydrogen-bonded isomers in the crystal and thus gives multiple, inhomogeneously broadened EPR signals. Similarly, single-crystal (55)Mn NMR spectra on Mn(12)-BrAc display much sharper signals than a single crystal of Mn(12)-Ac, and this allows one Mn(III) signal to show an almost baseline-resolved quintet from quadrupolar splitting ((55)Mn, I = 5/2, 100%), allowing quadrupole coupling parameters (e(2)qQ) to be determined. In addition, it was found that crushing crystals of Mn(12)-BrAc into a microcrystalline powder causes severe broadening and shifts of the NMR resonances, emphasizing the superiority of single-crystal studies. The combined results establish that Mn(12)-BrAc is far superior to Mn(12)-Ac for the study of the intrinsic properties of the Mn(12) family of SMMs in axial symmetry, and for the search for new phenomena such as quantum interference effects caused by higher-order (>2nd-order) transverse terms in the spin Hamiltonian.
Comparison of Equations To Estimate Glomerular Filtration Rate and Their Impact on Frequency of Cisplatin-associated Acute Kidney Injury

Background Accurate estimation of kidney function is essential for patient selection and drug dosing in patients with cancer. eGFR equations are necessary for decision making and monitoring. Our aim was to identify which of these equations—estimated creatinine clearance (eCrCl) by Cockcroft-Gault (CG), eGFR by Modification of Diet in Renal Disease (eGFRMDRD), CKD Epidemiology Collaboration (eGFRCKD-EPI) or the recently proposed Janowitz-Williams equation (eGFRJ-W)—would be most suitable for GFR estimation among patients with cancer receiving cisplatin. Methods We assembled a cohort of 5274 patients with cancer treated with cisplatin-based chemotherapy at two large cancer centers. We ascertained the frequency of cisplatin-associated AKI (C-AKI) defined as a ≥0.3 mg/dl rise in serum creatinine over baseline. We compared baseline eGFR and eCrCl using Bland-Altman (B-A) plots, coefficients of variation (CV), and concordance correlation coefficients. We calculated the positive predictive value (PPV), negative predictive value (PPV), accuracy, and area under the curve (AUC). Results Patients were predominantly middle aged (median 58 years, IQR 49–66 years), overweight (median BMI 26.2, IQR 23.1–29.8 kg/m2), and White (88%), with a median baseline creatinine of 0.8 mg/dl and median cisplatin dose of 99 mg. C-AKI developed in 12% of the cohort. eGFRCKD-EPI had the highest PPV and AUC. eGFRCKD-EPI and eGFRMDRD, along with their BSA-modified counterparts, had the closest agreement with the lowest CV (7.2, 95% CI, 7.0 to 7.3) and the highest concordance. C-AKI was lowest when using eGFRCKD-EPI to define eGFR ≥60 ml/min per 1.73 m2. Conclusions On the basis of its superior diagnostic performance, eGFRCKD-EPI should be used to estimate GFR in patients being considered for cisplatin-based chemotherapy.
Quality Differentiation and Matching Efficiency in Peer-to-Peer Markets: Evidence from Airbnb Plus

Matching efficiency makes or breaks peer-to-peer (P2P) platforms’ business model. As the grassroots nature of these markets involves a shift toward elite offerings, will differentiating suppliers by quality increase matching efficiency? Should P2P platforms differentiate suppliers without marginalizing some? We seek answers by leveraging an empirical opportunity on Airbnb, which differentiates listings meeting high-quality criteria from regular ones through its Plus program in several U.S. cities. Our findings are threefold. First, we find a sizable increase ranging from 15.5% to 18.7% in market-level matching efficiency after the program. Second, the rise in matching efficiency is attributed to reduced search frictions, especially in markets with higher levels of discovery and evaluation costs. Third and intriguingly, the increase in the market-level matching efficiency is primarily driven by regular listings rather than high-quality ones. Our findings are robust across multiple checks and offer important insights for platform design and supplier management in P2P matching.
Recombinant lactase with a cellulose binding domain permits facile immobilization onto cellulose with retained activity

Abstract Because of their potential impact in food and bioprocessing, diagnostics, green(er) chemistry, and waste remediation, new enzyme immobilization technologies continue to be explored. In this work, a recombinant lactase (β-galactosidase) (LacZ) presenting a carbohydrate binding module (LacZ-CBM), was engineered, expressed, and immobilized onto cellulose (LacZ-CBM:cell). Binding density, activity, and pH and temperature activity profiles were characterized in comparison to wild type lactase (LacZ). LacZ-CBM effectively self-immobilized onto cellulose (Sigmacell®) in less than 2 h, demonstrating that recombinant enzymes with cellulose binding modules can enable immobilization onto solid supports without the need for chemical crosslinking agents. The immobilized recombinant LacZ-CBM:cell retained over 30% of its initial activity over 9 cycles. Both immobilized and non-immobilized LacZ-CBM presented similar optimum reaction conditions as wild type lactase, which demonstrates that the addition of a carbohydrate binding module (CBM) to lactase does not alter its optimum reaction conditions. This work has direct relevance to immobilized lactase applications (e.g. lactose reduced milk; oligosaccharide production) and serves as a model for other greener enzyme immobilization applications.
Anti–factor Xa activity assays of direct‐acting oral anticoagulants during clinical care: An observational study

Author(s): Sukumar, Smrithi; Cabero, Melissa; Tiu, Sharon; Fang, Margaret C; Kogan, Scott C; Schwartz, Janice B | Abstract: BackgroundDirect-acting oral anticoagulants (DOACs) are increasingly used to prevent and treat thromboembolism. Although measurement of DOAC concentrations is not currently recommended as part of routine patient care, measurement of DOAC concentrations with anti-factor Xa activity assays have recently become clinically available.ObjectivesOur goal was to determine the clinical conditions under which DOAC concentration measurements are requested.Materials and methodsRetrospective electronic medical record analysis of indications for DOAC concentration measurements by anti-factor Xa activity assay at a single academic medical center from July 2015 through April 2020.Results and conclusionsNinety-one DOAC concentration measurements were made in 69 patients: 28 received apixaban and 41 received rivaroxaban. The most frequent indication for concentration measurement was drug exposure assessment (38/69; 55%) in patients with potentially altered pharmacokinetics (altered absorption or clearance), recurrent thromboembolic events, or possible medication nonadherence. Fourteen of 69 patients had repeated measurements during preoperative evaluation before emergent surgery; one-third of those with detectable levels upon presentation had repeated measurements until concentrations were undetectable. Levels were undetectable in 4 of 4 patients scheduled for elective surgery. Eleven of 69 patients had DOAC measurements in the setting of major bleeding; 5 of these 11 received a specific DOAC reversal agent. While most of the observed indications appear in clinical guidelines, altered absorption does not. Overall, clinicians are requesting DOAC concentration measurements to evaluate drug exposure in patients with conditions that might alter the absorption or clearance of the DOAC, to evaluate surgical bleeding risk, and in the setting of major bleeding.
Adverse effects and potential benefits among selective androgen receptor modulators users: a cross-sectional survey

Selective androgen receptor modulators (SARMs) are a class of androgen receptor ligands that bind androgen receptors and display tissue selective activation of androgenic signaling. SARMs have selective anabolic effects on muscle and bone, and were originally synthesized for treatment of muscle wasting conditions, osteoporosis, breast cancer. To date, no SARM has been clinically approved and little is known about the beneficial effects and other adverse effects on users. We examined the adverse effects and potential benefits of SARMs amongst users. We performed an internet survey assessing the demographics of users via a 32-question survey. Using reddit as a platform, we distributed the survey through various subreddits that included potential SARMs users. Out of the 520 responses, 343 participants admitted having used SARMs. Most were males (98.5%), between the ages of 18-29 (72.3%). More than 90% of users acquired SARMs via the internet and did not consult with a physician. More than half of SARMs users experienced side effects including mood swings, decreased testicular size, and acne. More than 90% of men reported increased muscle mass and were satisfied with their SARMs usage. Despite having seemingly positive effects, more than 50% of SARMs users report significant adverse effects. Chi square was the main method of statistical analysis. Future studies should focus on comprehensive reproductive evaluation of men using SARMs.
A coastal ocean observing system and modeling program for the West Florida Shelf

The Coastal Ocean Monitoring and Prediction System (COMPS) is a real-time, web-based (http://comps.marine.usf.edu) coastal ocean observing and modeling system for the west coast of Florida. COMPS observations consist of coastal and offshore stations, each with in-situ ocean and air-sea interaction measurements. Some of these stations are maintained by the University of South Florida and others are maintained by various local, state and federal agencies. Our web-site imports and serves all available real-time data. The COMPS array also provides a backbone for process experimentation, inclusive of other non-realtime data sets, and it is supported by a numerical circulation modeling program for process experiment hindcasts and for nowcasts and forecasts. Through this coordinated program of in-situ measurements and models we are making headway in understanding material property distributions on the West Florida Shelf and how these impact shelf ecology. The COMPS in situ data and modeling program and some of its principal scientific findings are discussed. Based on these we provide recommendations on a basic set of measurements for future integrated sustained coastal ocean observing systems.
Photosynthetic responses of 13 grassland species across 11 years of free-air CO2 enrichment is modest, consistent and independent of N supply

If long-term responses of photosynthesis and leaf diffusive conductance to rising atmospheric carbon dioxide (CO2) levels are similar or predictably different among species, functional types, and ecosystem types, general global models of elevated CO2 effects can effectively be developed. To address this issue we measured gas exchange rates of 13 perennial grassland species from four functional groups across 11 years of long-term free-air CO2 enrichment (eCO2, 1180ppm above ambient CO2) in the BioCON experiment in Minnesota, USA. Eleven years of eCO2 produced consistent but modest increases in leaf net photosynthetic rates of 10% on average compared with plants grown at ambient CO2 concentrations across the 13 species. This eCO2-induced enhancement did not depend on soil N treatment, is much less than the average across other longer-term studies, and represents strong acclimation (i.e. downregulation) as it is also much less than the instantaneous response to eCO2. The legume and C3 nonlegume forb species were the most responsive among the functional groups (113% in each), the C4 grasses the least responsive (14%), and C3 grasses intermediate in their photosynthetic response to eCO2 across years (19%). Leaf stomatal conductance and nitrogen content declined comparably across species in eCO2 compared with ambient CO2 and to degrees corresponding to results from other studies. The significant acclimation of photosynthesis is explained in part by those eCO2-induced decreases in leaf N content and stomatal conductance that reduce leaf photosynthetic capacity in plants grown under elevated compared with ambient CO2 concentrations. Results of this study, probably the longest-term with the most species, suggest that carbon cycle models that assume and thereby simulate long-lived strong eCO2 stimulation of photosynthesis (e.g.425%) for all of Earth’s terrestrial ecosystems should be viewed with a great deal of caution.
Morphogenesis and territorial coverage by isolated mammalian retinal ganglion cells

Identified retinal ganglion cells were isolated from postnatal cat retinas and their dendrites were removed by trituration and centrifugation. The denuded cells were placed in a cell culture system and allowed to reexpress dendritic arbors in the absence of afferent input, target tissue, and interactions with neighboring ganglion cells. The retinal ganglion cells were grown above a feeder layer of astrocytes on glass coverslips equipped with paraffin pedestals. The spatial patterns of the reexpressed neurites were quantitatively analyzed using a number of measures, including an estimate of the Hausdorff dimension, H, which was used as a scale-independent metric for how well the neurite patterns filled in a restricted spatial domain. As assessed by the estimation of the Hausdorff dimensions, the neurites from a single cell achieve uniform coverage of a restricted territory independent of the total neurite length or the total number of inter-branch-point segments. A comparison with H values of ganglion cells from the intact retina revealed a similar trend. These results suggest that these cultured ganglion cells can express an intrinsic growth strategy for the uniform coverage of a restricted territory. The arbors expressed in the culture system displayed a limited range of diameters and exhibited morphology similar to the alpha-, beta-, and gamma-ganglion cells of the intact retina in the absence of afferent input or the influences of neighboring cells and target tissue. Time-lapse video data revealed that individual cultured cells showed extensive dendritic remodeling during their growth; however, after about 3 d in culture, this remodeling did not appreciably affect the territorial coverage of a cell. In the intact retina, the existence of dendritic sheets that independently and uniformly sample visual space may result from this intrinsic ability to elaborate dendrites that uniformly cover or fill in a restricted territory.
Dynamic interaction between adjacent foundations

L'etude porte sur les effets de la distance, de la direction de l'alignement, de l'enfouissement et de l'inertie de la structure. Interaction de structure adjacente transmise par le sol
Circling the Wagons: Soft News and Isolationism in American Public Opinion

This study investigates the differences in coverage of foreign policy by the soft and hard news media, and the implications of such differences for public attitudes regarding the appropriate U.S. role in the world. I find that, relative to traditional news outlets, the soft news media place greater emphasis on dramatic, human-interest themes and episodic frames and less emphasis on knowledgeable information sources or thematic frames, while also having a greater propensity to emphasize the potential for bad outcomes. I then develop a conceptual framework in order to determine the implications of these differences. I argue that the style of coverage of soft news outlets tends to induce suspicion and distrust of a proactive or internationalist approach to U.S. foreign policy, particularly among the least politically attentive segments of the public. I test this and several related hypotheses through multiple statistical investigations into the effects of soft news coverage on attitudes toward isolationism in general, and U.S. policy regarding the Bosnian Civil War in particular. I find that among the least politically attentive members of the public, but not their more-attentive counterparts, soft news exposure—but not exposure to traditional news sources—is indeed associated with greater isolationism in general, and opposition to a proactive U.S. policy toward Bosnia in particular.
Measurement of ultrasound reflected from ultra-thin defects

Abstract Thin defects (order of 100 nm) can be simulated by producing air gaps between two highly-polished glass discs. Such air gaps serve to model either a weak bond in an adhesively-fastened structure, or a tight crack. This paper discusses the results obtained in the measurement of the reflection coefficient for longitudinal waves at normal incidence to thin gaps. Also included is the description of an optical technique of sufficient precision to measure gap thickness. Reflectivity measurements were made in the frequency range of 2–10 MHz for air gaps in the range of 20–200 nm. For discs having a visible residue after cleaning, the reflection coefficient was in reasonable agreement with the results obtained by other researchers. However, these results are not in agreement with those predicted by acoustic theory for thin air gaps. For very carefully cleaned discs, with no visible residue, the measured coefficient is close to the predicted theoretical values. In fact, it was nearly unity for gaps of order 20 nm in the bandwidth 5–12 MHz. Apparently gap cleanness strongly influences the reflection coefficient in a manner that is unclear at present.
Predictors of weight change in men: Results from The Health Professionals Follow-Up Study

OBJECTIVE: Since the prevalence of adult obesity is increasing in the United States, we examined the effect of changing common habits (exercise, TV viewing, smoking and eating habits) on four year change in body weight. DESIGN: A prospective cohort study of US male health professionals with follow-up from 1988‐1992. Participants were 19 478 men aged 40‐75 in 1986, who were free of cancer, coronary heart disease, stroke and diabetes. METHODS: Multiple regression was used to determine the association between four year change in body weight (from 1988‐1992) and common habits, after adjusting for baseline age, hypertension and hypercholesterolemia. RESULTS: For middle aged men, vigorous activity was associated with weight reduction and TV=VCR viewing and eating between meals with weight gain. Quitting smoking and a history of voluntary weight loss prior to the study period were consistently related to weight increase. Recently being on a diet was more strongly associated with weight loss among older men. Over the four year follow-up period, middle-aged men who increased their exercise, decreased TV viewing and stopped eating between meals, lost an average weight of 71.4 kg (95% confidence interval (CI)71.6 ‐ 71.1 kg), compared to a weight gain of 1.4 kg among the overall population. The prevalence of obesity among middle-aged men was lowest among those who maintained a relatively high level of vigorous physical activity, compared to those who were relatively sedentary. CONCLUSION: These data suggest that improvement in the mix of health habits, particularly increasing vigorous activity, as well as decreasing TV use and changing eating habits, results in weight maintenance or a modest weight loss over four years.
Identification of linalool produced by two species of bark beetles of the genus Ips

Abstract The terpene alcohol linalool (3,7-dimethyl-1,6-octadien-3-ol) has been isolated from volatiles produced by Ips paraconfusus females and from frass produced by I. pini males, both insects boring in ponderosa pine. Neither species of either sex responds to linalool in the laboratory bioassay. Pitfalls involved in identification of some terpene alcohols are noted.
On the mechanism of hydrogen-environment embrittlement of iron- and nickel-base alloys

Iron base and nickel base alloys susceptibilities to internal hydrogen and hydrogen environment embrittlements, studying crack initiation inside and at metal surface
Focusing and higher-order abstract syntax

Focusing is a proof-search strategy, originating in linear logic, that elegantly eliminates inessential nondeterminism, with one byproduct being a correspondence between focusing proofs and programs with explicit evaluation order. Higher-order abstract syntax (HOAS) is a technique for representing higher-order programming language constructs (e.g., λ's) by higher-order terms at the"meta-level", thereby avoiding some of the bureaucratic headaches of first-order representations (e.g., capture-avoiding substitution).This paper begins with a fresh, judgmental analysis of focusing for intuitionistic logic (with a full suite of propositional connectives), recasting the "derived rules" of focusing as iterated inductive definitions. This leads to a uniform presentation, allowing concise, modular proofs of the identity and cut principles. Then we show how this formulation of focusing induces, through the Curry-Howard isomorphism, a new kind of higher-order encoding of abstract syntax: functions are encoded by maps from patterns to expressions. Dually, values are encoded as patterns together with explicit substitutions. This gives us pattern-matching "for free", and lets us reason about a rich type system with minimal syntactic overhead. We describe how to translate the language and proof of type safety almost directly into Coq using HOAS, and finally, show how the system's modular design pays off in enabling a very simple extension with recursion and recursive types.
Space science innovation: How mission sequencing interacts with technology policy

Abstract Innovation is fundamental to a space agency's mission. Yet, the industry's current dominant approach to new technology development – concerted investment in step-changes in capabilities to support a particular application – contradicts the conventional wisdom of innovation theory. In order to understand why, this paper uses a unique empirical case study, in which exogenous historical circumstances created unexpected additional opportunities for technology investment, to explore the merits of this approach. The value of follow-on periods of R&D is assessed in terms of simple marginal returns, implications for workforce dynamics and the interaction of mission sequencing and technology strategy. The analysis reveals an important contingency between mission paradigm and the value of follow-on investment. Specifically, while marginal performance improvements can be achieved at lower costs, their value depends on the availability of an appropriate mission opportunity. In the current paradigm, the risk of obsolescence is high compared to the potential benefit. However, if a new small mission, frequent flights, paradigm were to take hold, there may be great value in refocusing R&D strategy on later round improvements.
Accelerator Cooling-System Design and Economics

This paper is a condensation of an unfinished report on accelerator cooling systems. When published, it will be made available to interested parties. It is based on approximately twenty years experience with a number of accelerators, on materials testing and engineering analysis, and on information obtained from other laboratories. 1. The relative cost of cooling depends on geographic location and atmospheric conditions, on cooling water supply temperature and temperature range, on the cooling method used, and on the degree of cooling-system centralization. 2. The cooling water supply temperature and temperature range affect the operating costs of other accelerator components. 3. Many materials are available for use in low-conductivity water systems. All have limitations.
Engineering improved T cell receptors using an alanine-scan guided T cell display selection system

T cell receptors (TCRs) on T cells recognize peptide-major histocompatibility complex (pMHC) molecules on the surface of antigen presenting cells and this interaction determines the T cell immune response. Due to negative selection, naturally occurring TCRs bind self (tumor) peptides with low affinity and have a much higher affinity for foreign antigens. This complicates isolation of naturally occurring, high affinity TCRs that mediate more effective tumor rejection for therapeutic purposes. An attractive approach to resolve this issue is to engineer high affinity TCRs in vitro using phage, yeast or mammalian TCR display systems. A caveat of these systems is that they rely on a large library by random mutagenesis due to the lack of knowledge regarding the specific interactions between the TCR and pMHC. We have focused on the mammalian retroviral display system because it uniquely allows for direct comparison of TCR-pMHC-binding properties with T-cell activation outcomes. Through an alanine-scanning approach, we are able to quickly map the key amino acid residues directly involved in TCR-pMHC interactions thereby significantly reducing the library size. Using this method, we demonstrate that for a self-antigen-specific human TCR (R6C12) the key residues for pMHC binding are located in the CDR3β region. This information was used as a basis for designing an efficacious TCR CDR3α library that allowed for selection of TCRs with higher avidity than the wild-type as evaluated through binding and activation experiments. This is a direct approach to target specific TCR residues in TCR library design to efficiently engineer high avidity TCRs that may potentially be used to enhance adoptive immunotherapy treatments.
Experiences of detained young offenders in need of mental health care.

Purpose:To explore the experiences of young people detained in the juvenile justice system and in need of mental health services. Methods:An ethnomethodological analysis was done using Kleinman's Explanatory Model Interview Guide to explore the perceptions of detained young people in need of mental health treatment. Findings:Five themes were extracted from focus groups, indicating lack of control in their lives and lack of family and community support. Although participants expressed feelings of hopelessness and depression, they perceived that it was better to be tough than to be sick. Conclusions:The findings indicate the need for multimodal treatment interventions to sequentially address the multiple internal and external factors contributing to persistent problem behaviors in children.
CD28/B7 regulation of autoimmune diabetes

The initiation and progression of autoimmune diseases, such as insulin-dependent diabetes mellitus (IDDM), are complex processes that depend on autoantigen exposure, genetic susceptibility, and secondary events that promote autoaggression. T-cell costimulation, largely mediated by CD28/B7 interactions, is a major regulatory pathway in the activation and differentiation of T-cells that cause IDDM in murine models. In this article, we summarize our results in two models of IDDM: the nonobese diabetic (NOD) mouse and diabetes induced with multiple low doses of streptozotocin (MDSDM). In both of these models, blockade of CD28/B7 costimulation regulates the development of disease. The effects of blockade vary with the intensity of cognate signal delivered to the T-cells, the timing of the costimulatory signal, and perhaps even the CD28 ligand expressed on antigen-presenting cells (APCs). Our results suggest that targeting CD28/B7 signals is a feasible approach for treatment and prevention of recurrence of autoimmune diabetes. However, the dynamic nature of these interactions highlights the importance of a clear understanding of their role in regulation of the disease.
Unterdruck and Uberdruck, 1904.

Abstract At the beginning of the 20th century, elective surgery within the chest was not possible; to open the pleural cavity under anesthesia meant death to the patient in almost all cases. The few exceptions to this rule—resulting from diffuse pleural adhesions or brief duration of surgical pneumothorax in robustly healthy persons—still did not permit deliberate intrathoracic procedures to be done with any expectation of success. Two papers that appeared consecutively in the same journal in 1904 proposed opposite approaches to respiratory support in the presence of surgical pneumothorax, by means of differential pressure chambers. Both methods were reasonably successful in clinical use. The life span of the static-pressure chambers was brief, however, and within a few years they were being superseded by cyclic positive-pressure inflation via the airway. The opposing methods are remembered under their German names, Unterdruck and Uberdruck.
The challenge of scheduling user transmissions on the downlink of a long-term evolution (LTE) cellular communication system

Wideband code division multiple access (WCDMA) is currently being extended into high-speed downlink access (HSDPA) and high-speed uplink packet access (HSUPA). The continuing research of next generation communication proposed by 3GPP is named long term evolution (LTE). The main goal of LTE Release is to offer high peak downlink and uplink rates by the use of Orthogonal Frequency-Division Multiple Access (OFDMA) that attributes a very flexible multi-user bandwidth, high spectral efficiency and scalable bandwidth. The benefit of LTE is the fact that it offers higher data rates in both uplink and downlink and enhances the services for the terminals. A notable fact is that several WiMAX projects have been reoriented toward Long Term Evolution (LTE), mainly aimed at increasing performance. In this paper the challenge of scheduling user transmissions on the downlink of LTE cellular communication system is discussed. Various results show that the system performance improves with increasing correlation among OFDMA subcarriers.
Early experience in the use of the Advanced Breast Biopsy Instrumentation : A report of one hundred twenty-seven patients

Abstract Background: Recently there has been a great interest in developing alternative breast biopsy techniques that yield the appropriate histologic information in the least invasive and most cost-effective manner. The objective of this study was to evaluate the efficacy and results with the Advanced Breast Biopsy Instrumentation (ABBI) method for stereotactic excisional biopsies of nonpalpable mammographically detected breast lesions. Methods: All patients with nonpalpable mammographic abnormalities who fulfilled the selection criteria for the ABBI procedure were studied. Pathologic diagnosis, the size of the specimen, the length of the procedure, postoperative complications, patient satisfaction, and the cost of the ABBI procedure were analyzed. Results: One hundred twenty-seven of 139 patients (94.2%) underwent the ABBI procedure. Twelve patients (8.61%) required conversion to the needle localization procedure. Mammographically, 64 lesions revealed microcalcifications, 51 showed nodular densities, and 12 demonstrated both findings. Histologically, 21 lesions (16.5%) were malignant, whereas 106 were benign (83.5%). The mean operative time for the procedures was 62.5 minutes. Postoperatively 5 patients had local ecchymosis and 1 had a hematoma. The average cost per patient was found to be $1000, considerably less than for needle localization biopsy. Conclusion: With proper patient selection the ABBI procedure has proved to be a valuable tool in the armamentarium of the breast surgeon. Its efficiency, accuracy, and patient acceptance have been well documented in our hands. (Surgery 1999;125:380-4.)
Why do river otters scent-mark? An experimental test of several hypotheses

We tested several alternative hypotheses about the function of scent marking by the North American river otter, Lontra canadensis. Otters may mark at latrine sites with spraints ( faeces) to (1) signal species identity, (2) advertise their reproductive status, (3) establish and maintain territories, and (4) communicate social status and identity to group members. Olfactory preference tests were conducted at the Alaska Sealife Center in Seward, Alaska, on a group of 15 wild-caught male otters in February 1999. We found that male otters investigated otter scent more than sealion faeces. The male otters also showed a preference for male scent over the scent of anoestrous females. No preference for the scent of unfamiliar males, compared with the scent of familiar males, was observed, and no preference for the scent of close kin was detected. However, an investigation of dominant relationships of the captive otters showed that dominant males spent more time investigating male scent than did subordinate males. Thus, spraints deposited at latrine sites may function to communicate social status of males.
Observation of size-independent effects in nanoparticle retention behavior during asymmetric-flow field-flow fractionation

In this work, we highlight the size-independent influence of the material properties of nanoparticles (NPs) on their retention behavior in asymmetric-flow field-flow fractionation (A4F) by comparing four NP populations with similar nominal size. The phenomena described here suggest there are limits to the effectiveness and accuracy of using a single type of NP standard (polystyrene beads most typically) in order to generically calibrate retention time in normal mode elution. The dual objectives of this paper are to (1) demonstrate the uncertainties resulting from current practice and (2) initiate a discussion of these effects and their origins. The results presented here illustrate clearly that the retention time is higher for metallic NPs relative to lower (bulk) density NPs. By modifying the fundamental field-flow fractionation equation to account for differences in particle density, we show that the effect of the gravitational force is finite but insignificant for NPs. We postulate that the observed material-dependent retention behavior may be attributed to differences in the attractive van der Waals force between the NPs and the accumulation wall (membrane surface). We hope that our results will stimulate discussion and reassessment of the calibration procedure, perhaps by more fully accounting for all influential material parameters relevant to the fractionation of nanoscale particles by A4F.
RELATIVE PERTURBATION RESULTS FOR EIGENVALUES AND EIGENVECTORS OF DIAGONALISABLE MATRICES

Let\(\hat \lambda \) and\(\hat x\) be a perturbed eigenpair of a diagonalisable matrixA. The problem is to bound the error in\(\hat \lambda \) and\(\hat \lambda \). We present one absolute perturbation bound and two relative perturbation bounds.
Induction of hepatic aryl hydrocarbon hydroxylase activity in rainbow trout (Salmo gairdneri) exposed to coal liquids.

Abstract 1. 1. The hepatotoxic response of rainbow trout ( Salmo gairdneri ) to a middle distillate (MD) and heavy distillate (HD) coal liquid was determined following administration by injection or in food. Hepatic aryl hydrocarbon hydroxylase (AHH) activity was compared to the known AHH inducer, benzo(a)pyrene. 2. 2. Acute toxicities ( ld 50 ) of 1500 and 1410 mg/kg were obtained 120 hr after intraperitoneal injection (i.p.) for MD and HD coal liquids, respectively. Only the HD induced AHH activity when injected at 5% and 10% of the acute ld 50 . 3. 3. Ingestion of 7 or 70 mg HD/kg body weight for 1 week resulted in AHH induction at 5–7 times that of control values. Levels of hepatic AHH activity in fish treated at 7 mg HD/kg declined to 2.6 times control values 7 days after exposure. Maximum induction was observed for the 70 mg HD/kg group that was provided control food for 1 week following 2 weeks of exposure. 4. 4. The hepatic index (HI) or liver to body weight ratio generally increased along with increased activity in the enzyme response system.
Theoretical effects of fluid infusions during cardiopulmonary resuscitation as demonstrated in a computer model of the circulation

Abstract Recent studies have shown the potential adverse effects of venous volume loading on blood flow during closed chest cardiopulmonary resuscitation (CPR). To examine the effect of arterial and venous infusions, we employed a published computer simulation of the circulation during CPR. This model uses computer simulated electrical networks to model the heart and great vessels. CPR was modeled with compressions at a rate of 80/min and a force of 80 mmHg. Fluid infusions, simulated as current pulses into the abdominal aorta and superior vena cava, were given to measure their effect on myocardial and cranial blood flow. With 600 ml/min infusions into the abdominal aorta, there was a 12% peak increase in myocardial flow and a 3.8% peak increase in cranial flow. Every 100 ml/min, increase in infusion from 0 to 900 ml/min produced a 1.4 ml/min linear increase in myocardial flow and a 4.2 ml/min linear increase in cranial flow. In agreement with previous CPR model studies, simultated vasoconstriction of abdominal and lower extremity vessels resulted in increased myocardial and cranial flows. As resistance of these vessels was increased, abdominal aortic infusions resulted in greater flow augmentations. In contrast to arterial results, infusions at 600 ml/min into the vena cava resulted in a 2.2% decrease in myocardial flow and a 0.62% decrease in cranial flow. Rise and fall times for initiation and cessation of flow augmentations were equal to four compression cycles. We conclude that these findings demonstrate the theoretical benefits of rapid arterial infusions during CPR with increases in myocardial and cranial blood flow. This method may provide an early temporary adjunct to myocardial perfusion during CPR.
Nonexistence of classical steady Hele–Shaw bubble

Abstract This paper concerns nonexistence of steadily translating bubbles in a Hele–Shaw cell for small but nonzero surface tension. It is proved that for any fixed bubble velocity U relative to the fluid velocity at infinity in the interval ( 2 , ∞ ) , there can be no classical steady bubble solution.
Preliminary observations of sildenafil treatment for erectile dysfunction in dialysis patients.

Erectile dysfunction is common in dialysis patients. We report our experience with sildenafil citrate in patients undergoing dialysis therapy. Male subjects attending the Outpatient Dialysis Unit at the University of Pennsylvania (Philadelphia, PA) who were prescribed sildenafil by their primary physician or nephrologist were asked to complete the International Index of Erectile Function before their first dose of sildenafil and after at least 4 weeks of therapy. Subjects' mean age was 50.3 ± 14.63 (SD) years. Ninety-three percent of the subjects were black. Based on a global efficacy question, 66.7% of the subjects believed that treatment had improved their erections. Subjects reported no increase in the sexual desire domain despite experiencing a significant increase in erectile function, orgasmic function, and satisfaction with intercourse. Sildenafil was well tolerated in a selected group of patients who reported improved sexual function with no major adverse effects.
Compressed sensing of EEG using a random sampling ADC in 90nm CMOS

Wireless physiological sensors are often limited by energy consumption of the hardware. Power consumption is typically related to the amount of data being transmitted, conventionally the Nyquist rate which is twice the bandwidth of the signal. However, if the signals are sparse in a known basis, compressed sensing facilitates accurate reconstruction of data when sampled below the Nyquist rate. Thus, power consumption at the sensor node could be improved, which would allow long-term use of wireless physiological sensors. We have implemented a random sampling based compressed analog to information converter (AIC) in 90nm CMOS technology. Sufficiently sparse signals were reconstructed using the l 1 -minimization algorithm. Here we present experimental results that demonstrate reconstruction of non-sparse signals, in this case EEG, by using an l 1, 2 regularization algorithm exploiting group sparsity. These results demonstrate the performance achievable by physical compressed sensing AIC systems for brain computer interface applications.
Flumazenil may attenuate some subjective effects of nitrous oxide in humans: a preliminary report.

Two double-blind, randomized, crossover trials were conducted to study whether the benzodiazepine antagonist, flumazenil, would interact with the subjective and psychomotor effects of nitrous oxide in healthy volunteers. In both experiments, eight subjects inhaled 30% nitrous oxide in oxygen for 35 min and were challenged, 10 min into the inhalation, with flumazenil. Experiment 1 tested a range of flumazenil doses used clinically (0, 0.25, 0.5, and 1.0 mg/70 kg) whereas Experiment 2 tested a supraclinical flumazenil dose (0 and 5.0 mg/70 kg). Nitrous oxide increased mood ratings of “high,” “drunk,” and “tingling,” and decreased psychomotor performance as assessed by the Digit Symbol Substitution Test. Flumazenil, at the supraclinical dose, significantly lowered the mood rating of “high.” Decreases, though not significant (p < 0.10), were also obtained on the ratings “drunk,” “elated,” and “drug liking”. Flumazenil, in both experiments, did not interact with the psychomotor effects of nitrous oxide. It appears that flumazenil, at a dose higher than that used clinically, may antagonize some of the subjective effects produced by nitrous oxide in humans.
Can our understanding of informed consent be strengthened using the idea of cluster concepts

Informed consent is thought to exist as a well-defined entity. Altered concepts of patient autonomy, differential cultural understanding of the entity, and the failure of clients to distinguish between research and clinical ethics, and various hierarchical cultural views of informed consent all suggest that alterations may be needed in the traditional concept. By using the methodology outlined by Gasking in which he defines the idea of “cluster concepts,” one may be able to enlarge the definition and augment the understanding of the informed consent and include the time and culture-specific variants which exist.
The Use of Principles for Organising the Introductory Psychology Course

Common difficulties in teaching introductory courses such as general psychology are breadth of content and differing student and teacher expectations. The use of psychological concepts or principles as organising factors is recommended to address these problems. Psychological principles for each content area were identified and presented to two groups of general psychology students. Course content was organised around these principles, along with class exercises and tests that fostered their application. When compared with two other groups organised by the text's field survey approach, the principles-organised groups self-reported greater abilities to apply content to everyday situations, relationships and future occupations. Students strongly recommended the use of principles in future courses as one way of addressing common difficulties in the general psychology course. The percentage of answers correct on tests of content did not differ significantly between groups, indicating a similar grasp of materi...