cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of Y90 Radioembolization in Hepatic Metastatic Colorectal Carcinoma

Radioembolization is a treatment option for select patients with hepatic metastases from colorectal cancer in the salvage setting. These patients with liver-dominant or liver-only metastatic disease who have failed standard-of-care first- and second-line systemic therapies have clear and consistent objective response rates and survival outcomes from this outpatient procedure. While there is interest in combining systemic and locoregional therapies to benefit from chemoradiation principles as well as treat patients earlier in their disease course, current evidence to support this practice is lacking. Prospective randomized trials employing radioembolization in combination with first-line chemotherapy have been negative to date. Most recently, a clinical trial of second-line chemotherapy with/without radioembolization has completed enrollment in October 2018, and the study results are yet to be published.
Supramolecular polymerization provides non-equilibrium product distributions of imine-linked macrocycles.

Supramolecular polymerization of imine-linked macrocycles has been coupled to dynamic imine bond exchange within a series of macrocycles and oligomers. In this way, macrocycle synthesis is driven by supramolecular assembly, either into small aggregates supported by π–π interactions, or high-aspect ratio nanotubes stabilized primarily by electrostatic and solvophobic interactions. For the latter, supramolecular polymerization into nanotubes restricts imine exchange, thereby conferring chemical stability to the assemblies and their constituent macrocycles. Competition in the formation and component exchange among macrocycles favored pyridine-2,6-diimine-linked species due to their rapid synthesis, thermodynamic stability, and assembly into high-aspect ratio nanotubes under the reaction conditions. In addition, the pyridine-containing nanotubes inhibit the formation of similar macrocycles containing benzene-1,3-diimine-linkages, presumably by disrupting their assembly and templation. Finally, we exploit rapid imine exchange within weak, low-aspect ratio macrocycle aggregates to carry out monomer exchange reactions to macrocycles bearing pyridine moieties. Once a pyridine-containing dialdehyde has exchanged into a macrocycle, the macrocycle becomes capable of nanotube formation, which dramatically slows further imine exchange. This kinetic trap provides chemically diverse macrocycles that are not attainable by direct synthetic methods. Together these findings provide new insights into coupling supramolecular polymerization and dynamic covalent bond-forming processes and leverages this insight to target asymmetric nanotubes. We envision these findings spurring further research efforts in the synthesis of nanostructures with designed and emergent properties.
Factors affecting microcalcification detection of wide-angle digital breast tomosynthesis and strategies for improving performance

Wide-angle digital breast tomosynthesis (DBT) gives better depth resolution and tissue separation while the microcalcification (MC) detectability is impacted by many factors, such as detector performance, focal spot motion (FSM), increased noise due to scatter radiation, angular dose distribution and image reconstruction methods. This study aims at developing an in-silico experimental pipeline to compare these factors’ influence on the MC detectability, so that new system design can be proposed to improve the performance. The VICTRE tool developed by Food and Drug Administration was used to generate a 49 mm-thick anthropomorphic digital breast phantom and the projection images using Monte Carlo simulation. We inserted 38 MC clusters with size of 120 μm at 40 mm from the bottom of the phantom. The Monte Carlo simulation used parameters of a clinical wide-angle DBT system, with 25 projections over 50-degree angular range, and 28 kVp W/Rh energy spectrum. Projection images were simulated under different scenarios: uniform/nonuniform angular dose distribution, with/without FSM of 2 mm, with/without scatter radiation, and TFT/CMOS detector types. A four-alternative forced choice (4AFC) methodology was employed to evaluate the MC detectability. The percentage correct and visibility score under all scenarios were compared. The results show that MC detectability decreases with the presence of either increased noise due to scattered radiation, or image blur due to FSM. Nonuniform angular dose distribution improves the detectability of MCs when using FBP reconstruction with narrow slice thickness filter. MC sharpness is improved with CMOS detector with smaller pixel size and lower electronic noise.
When it’s too good to be true: Consumers’ reactions and firms’ responses to unintended price mistakes

Abstract Growing dynamic pricing and price automation trends increase the risk of price mistakes. In the case of low price mistakes, consumers might seek to take advantage of the error, and the company must decide whether to honor or deny the transactions. A set of studies reveal that consumers are more likely to take advantage of the price mistake when they feel powerful and when they perceive the company as powerful. Moreover, their perceptions of service fairness serve as double-edged swords, motivating consumers to take advantage of the price mistake because they anticipate a high likelihood that the company will honor the lower price but also inhibiting this behavior, due to consumers’ concern for the potential damage to the company. Finally, service fairness also influences how consumers react to firms’ decisions. This research offers an initial investigation of price mistakes that reveals valuable theoretical and managerial implications.
RNAi-Based Gene Therapy Rescues Developmental and Epileptic Encephalopathy in a Genetic Mouse Model.

Developmental and epileptic encephalopathy (DEE) associated with de novo variants in the gene encoding dynamin-1 (DNM1) is a severe debilitating disease with no pharmacological remedy. Like most genetic DEEs, the majority of DNM1 patients suffer from therapy-resistant seizures and comorbidities such as intellectual disability, developmental delay, and hypotonia. We tested RNAi gene therapy in the Dnm1 fitful mouse model of DEE using a Dnm1-targeted therapeutic microRNA delivered by a self-complementary adeno-associated virus vector. Untreated or control-injected fitful mice have growth delay, severe ataxia, and lethal tonic-clonic seizures by 3 weeks of age. These major impairments are mitigated following a single treatment in newborn mice, along with key underlying cellular features including gliosis, cell death, and aberrant neuronal metabolic activity typically associated with recurrent seizures. Our results underscore the potential for RNAi gene therapy to treat DNM1 disease and other genetic DEEs where treatment would require inhibition of the pathogenic gene product.
Physically Meaningful Grid Analytics on Voltage Measurements using Graph Spectra

Time synchronized measurements of voltage magnitudes or phasors are increasingly common in electrical networks. Voltage measurement statistics are informative of the underlying network structure or topology making them useful for grid monitoring. However, this connection is poorly understood and many proposed voltage analytics are purely heuristic. We use graph theory to establish sound theoretical connections between voltage measurements and the structure of the underlying network. Our results are important for many applications, from topology estimation to missing data recovery. Based on this new theory, we discuss existing analytics, transforming them from heuristic to theoretically justified approaches, and introduce new analytics. We clarify all assumptions made, to indicate when analytics may fail or perform poorly. Our work enables voltage measurement streams to be transformed into physically meaningful, intuitive, visualizable, actionable information through simple algorithms.
Coordination of Uranyl to the Redox-Active Calix[4]pyrrole Ligand.

Reaction of [Li(THF)]4[L] (L = Me8-calix[4]pyrrole]) with 0.5 equiv of [UVIO2Cl2(THF)2]2 results in formation of the oxidized calix[4]pyrrole product, [Li(THF)]2[LΔ] (1), concomitant with formation...
Graphite Intercalation Compounds Derived by Green Chemistry as Oxygen Reduction Reaction Catalysts

Precious group metal (PGM) catalysts such as Pt supported on carbon supports are expensive catalysts utilized for the oxygen reduction reaction (ORR) due to their unmatched catalytic activity and d...
MYC expression is associated with older age, common morphology, increased MYC copy number, and poorer prognosis in patients with ALK+ anaplastic large cell lymphoma

Summary The role of MYC dysregulation has been studied extensively in B-cell lymphomas, but little is known about its significance in T cell lymphomas. This study, for the first time in the literature, assessed the clinicopathologic and prognostic significance of MYC expression in ALK+ anaplastic large cell lymphoma (ALCL) cases. Using ≥50% as the cutoff value for positive MYC expression by immunohistochemistry, 17 of 46 (37%) cases were MYC+. Patients with MYC+ tumors were older (median age, 39 versus 29 years, p = 0.04) and more often showed a common morphologic pattern (100% versus 69%, p = 0.02), when compared with those with MYC-negative tumors. By fluorescence in situ hybridization analysis, 9 of 31 (29%) cases showed increased MYC copy number, and 1 of 31 (3%) case had an MYC rearrangement, and the remaining 21 (68%) cases showed no MYC aberrations. Among the cases with increased MYC copy number, 5 of 8 (62%) cases showed MYC copy gain and/or amplification and 3 of 8 (38%) had polysomy 8. MYC expression was associated with increased MYC copy number (p = 0.01). MYC expression, but not increased MYC copy number, correlated with shorter overall survival (OS) (p = 0.03). In conclusion, MYC expression identified a distinct group of ALK + ALCL patients with more aggressive behavior and shorter OS. Our data suggest that MYC expression is an adverse prognostic factor and may be useful in stratifying or predicting the prognosis of patients with ALK+ ALCL.
The Family Stress Model in the Context of Pediatric Cancer: A Systematic Review

A systematic review of the pediatric cancer literature was conducted to identify and summarize the variables that influence family-level psychosocial outcomes and to develop a conceptual framework based upon the Family Stress Model. PubMed, PsychInfo, Web of Science, and CINHAL databases were searched between 2008–2018 using PRISMA. Empirical studies in this review examined both uni- and bidirectional relationships between at least two members within the family (e.g., parent and child) or measured a component of family functioning (e.g., cohesion, adaptability). After screening 2815 records, 10 review studies and 52 empirical studies met the study criteria for inclusion. Variables related to family-level psychosocial outcomes were synthesized into five thematic categories: family, parent/caregiver, child with cancer, immediate and extended relationships, and socioeconomic. Potential mediating and moderating effects reported included family cohesion, family ritual, family environment, family functioning, and parenting stress and caregiver burden. Based on this review, a conceptual path model was developed to illustrate factors pertaining to pediatric cancer that may be applied to the Family Stress Model (FSM). This adaption of the FSM in pediatric cancer integrates the factors of economic stress and pediatric cancer on outcomes related to family functioning and child/sibling psychosocial functioning that are central to families dealing with cancer diagnoses and can be utilized to explicate the relative strength and influence of risk and protective factors.
Microfluidic circulating reactor system for sensitive and automated duplex-specific nuclease-mediated microRNA detection.

Abstract Duplex-specific nuclease signal amplification (DSNSA) is a promising microRNA (miRNA) quantification strategy. However, existing DSNSA based miRNA detection methods suffer from costly chemical consumptions and require laborious multi-step sample pretreatment that are prone to sample loss and contamination, including total RNA extraction and enrichment. To address these problems, herein we devised a pneumatically automated microfluidic reactor device that integrates both analyte extraction/enrichment and DSNSA-mediated miRNA detection in one streamlined analysis workflow. Two flow circulation strategies were investigated to determine the effects of flow conditions on the kinetics of on-chip DSNSA reaction in a bead-packed microreactor. With the optimized workflow, we demonstrated rapid, robust on-chip detection of miR-21 with a limit-of-detection of 35 amol, while greatly reducing the consumption of DSN enzyme to 0.1 U per assay. Therefore, this microfluidic system provides a useful tool for many applications, including clinical diagnosis.
Mechanisms affecting ALARA MI selected in adaptive ultrasound imaging

Adaptive acoustic output selection in ultrasound imaging promises to improve adherence to the ALARA (as low as reasonably achievable) principle. Demonstrated imaging sequences have balanced image quality and safety considerations based on transducer channel lag-one coherence to select Mechanical Index (MI), a measure of acoustic output. In this study, data were collected with an adaptive output selection tool on 9 pregnant volunteers to explore factors affecting the recommended output. The placenta, fetal abdomen, and fetal heart in each volunteer were repeatedly scanned. A statistically significant difference in recommended ALARA MI was observed between target structures (p < 0.001). Each target's underlying channel data signal magnitude correlated with the recommended ALARA MI used for scanning, suggesting the brightness of a target affects the selected ALARA MI. These findings imply that continued observance of the ALARA principle during clinical examinations requires adaptive output selection be performed with each new target structure, or each time a transducer or acoustic window shift causes a change in the target brightness,
Mothers’ attachment styles and their children’s self-reported security, as related to maternal socialization of children’s positive affect regulation

This study investigated how mothers’ attachment was related to their responses to their own and their children’s positive events and positive affect (PA). Ninety-seven mothers reported on their attachment and their responses to their own and their 7–12-year-old children’s positive events and emotions. Children reported on their mothers’ responses to the children’s positive events and their attachment security with their mothers. The results indicated that more avoidant mothers reported less intense PA in response to their own and their children’s positive events. More avoidant mothers also were less likely to encourage their children to savor positive events (through expressing PA, reflecting on PA or themselves, giving rewards, and affectionate responses). Mothers higher on anxiety reported greater likelihood of dampening (e.g., minimizing the event’s importance) their own positive events and reported being more likely to feel discomfort and to reprimand their children for expressing PA. Children’s secur...
The mitotic apparatus of a giant ameba: solubility properties and induction of elongation.

Abstract Mitotic apparatuses released from giant, multinucleate amebae directly into solutions of different pH, ionic strength, or composition exhibit precise solubility borderlines. The isolated MA is stable at pH 6.0 or below in most buffer solutions, at pH 5.0 or below in a chelating buffer solution, in KCl or CaCl 2 solutions below 0.5 M at pH 6.0, between 10 −3 M and 0.4 M CaCl 2 at every pH tested, and at pH 6.8 or below in solutions containing 10 −4 M CaCl 2 . Cells in mitosis could utilize changes near one of these solubility borderlines to control the mutual repulsion of MA-microtubule components and hence could control, in part, the relative rates of MA assembly and disassembly. The isolated MA appears structurally complete, but an in vitro reconstruction of normal MA function is not obtained with the isolated, stabilized unit. However, a brief MA elongation similar to anaphase movement can be induced during isolation into a solution containing magnesium and ATP. When the changes that occur in dividing cells are clarified, the effects of several of those changes may be understandable in terms of the MA properties described here.
Political Engagement, Social Change and the Political Economy of Financial Modernization: Experimental Evidence from the Philippines

This project applies a field experiment in Manila, Philippines to assess the influence of access to modern finance on political engagement. Recent development in formalizing banking through microfinance programs stands to disrupt the interdependence of political-economic relationships within local communities. The paper investigates how such substantial changes in individuals economic wellbeing also result in changes in the political sphere. The project ex- amines an economic development experiment involving 1900 low-income entrepreneurs who have no prior formal banking experience. The treatment group received a business loan and signed a formal contract with a metropolitan bank. The control group was left to continue informal, often politically embedded financial practices. Evidence from the oral survey project, analysis of international statistics and field work contradict the conception that improving economic status leads to greater political efficacy and participation. Rather, the paper offers robust statistical evidence that providing entrepreneurs with apolitical support resulted in political disengagement. The statistics are corroborated by extensive qualitative interviews of local politicians, money lenders, as well as original experiment participants. The work indicates that conventional thinking about political engagement does not apply in the context of developing democracies, wherein markets are mediated by clientelism. When people become less dependent and involved in clientelistic relationships, as a result of their access to modern financial services, they lose their motivation for political engagement. The findings suggest that the relationship between economic and political development are not entirely harmonious and furthers our understanding of the social changes occasioned by financial progress.
Going Green: How the Green Movement Impacts the Bottom Line in the Hospitality Industry

The American Hotel and Lodging Association (AH&LA) has released green guidelines for the hospitality industry. Those guidelines include information on effective energy usage, water conservation and waste management. The purpose of this paper is to analyze the literature to determine if the green movement has impacted the hospitality industry's bottom line. Determining whether or not it is practical for older hotels to refurbish and adhere to the guidelines proposed by the AH&LA's recommendations is something that every property must determine on its own. Properties being built now have the option to create sustainable and efficient properties. However, some choose not to due to the perceived cost increases and the fear that there will be little benefit to their own business in the long run. How do we make being green, greener?
A simple semimicro cell for the measurement of spectral reflectance

Abstract The construction and method of employment of a simple cell suitable for the measurement of the spectral reflectance of semimicro samples, such as those removed from chromatoplates, are described. An attempt is also made to correlate the performance of the cell with current theories of reflectance spectroscopy using data obtained with a system consisting of Merck silica gel G and McCormick blue, a food dye.
Attitudes, Practices, and Recommendations by Obstetricians About Infant Feeding

Background: Little information is available about the degree to which obstetricians promote breastfeeding through patient care practices and educational activities. The purpose of this study was to determine the attitudes, practices, and recommendations of obstetricians regarding infant feeding selection. Methods: A written survey was mailed to 148 obstetrician/gynecologists in Monroe County, New York (78% response rate, n= 116). Results: Of the 104 physicians in active obstetric practice, 86 percent conducted prenatal discussions about infant feeding with patients, 80 percent recommended breastfeeding, and 68 percent were commonly contacted postpartum by patients to address breastfeeding questions. Overall, 57 percent routinely incorporated these breastfeeding supportive practices into their prenatal and postpartum patient care. Attitudes about obstetric responsibility for infant feeding counselings and about the importance of counseling independently predicted the provision of these services. Infant feeding information was given to patients by 98 percent of obstetricians; 75 percent used written and 39 percent used videotaped materials. Formula company-produced infant feeding literature (41%), pregnancy literature (57%), and free formula offers (61%) were commonly used. Of those surveyed, 58 percent lacked training and 22 percent reported inadequate training in infant nutrition. Conclusions: Although most obstetricians in Monroe County provide infant feeding education and recommend breastfeeding, most report that their training about infant nutrition is inadequate, and they distribute infant formula company materials and offers to patients. Such discrepancies in patient care are inconsistent with promoting breastfeeding as optimal infant nutrition. (BIRTH 24:4, December 1997)
On the Symmetry of Deformable Crystals

This study was motivated by my recognition of some difficulties in the theory of phase transitions. LANDAU* [1] proposed a theory of phase transitions in crystals, covering cases where the crystal symmetry undergoes some change. Briefly and roughly, it excludes the possibility of various types of changes in symmetry. Unfortunately for the theory, various excluded transitions are observed. I do not know of a good reference describing the known exceptions. The discussion which follows refers to cubic-tetragonal transitions, 'which are observed in some superconductors. According to conversations I have had with experimentists, other types of exceptions are observed. It is not impossible to be fooled, for the distinction between a second order and weak first order transition is a fine one. However one assesses this, we have good reason to look at the theory with a critical eye, and to remove its imperfections. In discussing one such exception, ANDERSON • BLOUNT [3] claim to show that such transitions "... usually involve some change in internal symmetry other than mere strain ...". Said differently, thermoelasticity theory should be replaced by a theory involving a larger list of variables in the constitutive equations. If the suggested cure is to work, it should change the conclusions of LANDAU, most probably to decrease the number of changes excluded. Considering the nature of the calculations involved, it seems to me less than clear that merely enlarging the list of state variables will accomplish this, and they do not prove that it will. Thus, I think that we should look at other weak spots in the LANDAU theory. ANDERSON & BLOUNT mention, but discount another, involving matters of continuity. I focus on another. It might well be that thermoelasticity theory is inadequate, but it should be given a fair hearing. As far as I know, we do not have a theory, accepted by knowledgeable workers, to replace LANDAU's. Again considering the nature of LANDAU'S reasoning, it might help if we could attribute to thermodynamic potentials more invariance than is commonly done. Common molecular theories predict a rather unconventional theory of
N-MOS JK master/slave flip flop design for use in high speed control and counting applications

Abstract An N-MOS version of the JK master/slave flip flop with preset and clear inputs has been designed for use in high speed control and counting applications. For the chip layout design, fast transient response and the low power dissipation, component density has been reduced using A-O-I (AND-OR-INVERT) gate. The transient analysis has been done using Spice 2G.6 program. The chip size is 124 λ × 103 λ ( λ = 4 micron) and dissipates power of 0.715 mW.
Expression of c-jun, jun-B, and c-fos proto-oncogenes in human primary melanocytes and metastatic melanomas.

Analysis of the regulation of c-jun, jun-B, and c-fos RNA transcript expression was performed in human primary melanocytes and metastatic melanoma cell strains. The medium requirements for human melanocyte in vitro growth are phorbol esters, agents that elevate intracellular cAMP levels, hormones, and growth factors. Cellular jun, jun-B, and c-fos gene expression are known to be affected by growth promoting agents. In primary melanocytes, the expression of c-jun, jun-B, and c-fos RNA transcripts was dependent on the growth-promoting agents present in the medium. Uniformly high c-jun, jun-B, and c-fos RNA transcript levels were observed in melanocytes cultivated in complete medium. Higher levels of c-jun RNA transcripts and low levels of c-fos RNA transcripts were observed in melanocytes cultivated in plain medium. In contrast, a range of c-jun, jun-B, and c-fos RNA transcript levels was detected in metastatic melanoma cell strains cultivated in medium with or without serum. In general, an increase in jun-B and c-fos RNA transcript expression and a decrease in c-jun RNA transcript expression was observed in metastatic melanomas compared to neonatal melanocytes. These data suggest a potential role for c-jun,jun-B, and c-fos genes in the transformation of melanocytes to malignant melanoma.
Comment on “Evaluation of Evapotranspirative Covers for Waste Containment in Arid and Semiarid Regions in the Southwestern USA”

Landfill covers relying on a balance between soil water storage and evapotranspiration (ET) as the primary means to control drainage have been described in the recent paper by Scanlon et al. (2005) in the Vadose Zone Journal. These so-called "ET Covers" have been receiving considerable interest in the past few years as economically viable cover systems for landfills in arid and semi-arid environments (Hauser et al. 2001, Madalinksi et al. 2003) Scanlon et al. (2005) have provided a summary of their studies in Texas and New Mexico, demonstrating an acceptable performance of ET covers in minimizing drainage under their test conditions. Further, they illustrate with both measurement and modeling that capillary barriers (fine soils over coarse soils) similar in concept to those previously built and tested at Los Alamos, NM and Hanford, WA over the past 20 years, store more water than surface barriers that have uniform profiles.
Building spiritual capabilities to sustain sustainability-based competitive advantages

There is a rising global concern that centers on creating an ecologically, socially, and economically sustainable world for current and future generations. This rising sustainability consciousness is built on higher-level value systems that support the sacredness of people and nature. These values promote environmental and social responsibility as avenues to fair profits, and they are currently penetrating the global business environment. Because of their coevolutionary relationships with the business environment, business organizations are now faced with the need to craft efficient and effective triple bottom line strategies that allows them to earn profits in sustainable ways. Because sustainability is complex, multifaceted concept with deep spiritual roots, building triple bottom line strategies requires that organizations develop intangible spiritual capabilities (i.e. spiritual intelligence and spiritual capital) that are valuable, rare, holistic, socially complex, and causally ambiguous, making them...
Inflammatory Myofibroblastic Tumor: A Case Study

Inflammatory myofibroblastic tumor (IMT) is a rare benign lesion found in many locations throughout the body and genitourinary tract. Endoscopically and radiographically, these solid lesions cannot be distinguished from malignant bladder tumors. We present the case of a 21-year-old woman who presented with painful obstructive and irritative voiding symptoms of short duration. After extensive preoperative evaluation failed to reveal a definitive diagnosis, the patient underwent partial cystectomy. Final pathology revealed IMT. A high index of suspicion is required for diagnosis of IMT as it is often difficult to distinguish from its malignant counterparts.
Verification, Performance, Validation, and Modifications to the SOVS Continuum Constitutive Model in a Nonlinear Large‐Deformation Finite Element Code

The continuum theory of sintering embodied in the constitutive description of Skorohod and Olevsky can be combined with results from mesostructure evolution simulations to model shrinkage and deformation of ceramics. An implementation (and variations) of this sintering model based on a finite element (FE) formulation that allows three dimensional (3D) components to be modeled using Sandia National Laboratories' nonlinear large-deformation FE code, JAS3D, is presented. This tool provides a capability to model sintering of complex 3D components. Recent modifications to the model dictated that the suite of verification and validations problems, developed for the model, be exercised anew on the modified version. The verification, performance, and validation of the model within JAS3D is described and discussed herein. Modifications and improvements to the original implementation of the model are then also summarized and reviewed as the model's evolution is tracked to its current form.
Suitability ofDacus dorsalis andCeratitis capitata [Diptera: Tephritidae] as hosts of the parasitoid,Biosteres arisanus [Hymenoptera: Braconidae]

Biosteres arinsanus (Sonan) (=B. oophilus Fullaway) showed a strong preference forDacus dorsalis Hendel overCeratitis capitata (Wiedemann) in choice tests using papaya fruits infested with eggs of both hosts in laboratory studies. In laboratory and field studiesD. dorsalis was the most suitable host. A total of 13,871 parasitoids was produced fromD. dorsalis infested fruits compared with 2,772 fromC. capitata infested fruits.
Telephone subsidization of rural areas in the USA

Abstract This Comment puts under scrutiny the structure of the rural telephone industry in the USA and the subsidies which rural telephone companies and their customers have received and continue to receive. The current system of subsidizing rural telephone subscribers is inefficient and inequitable, the author finds. He examines the future of the rural telephone companies in the light of the regulatory changes that have occurred, and outlines some public policies which would help achieve universal service and improve equity and efficiency.
Clostridium difficile-associated diarrhea: current strategies for diagnosis and therapy.

Clostridium difficile, a spore-forming toxigenic bacterium, is one of the most common causes of infectious diarrhea and colitis in the United States. Most patients with C. difficile infection have recently received antimicrobial therapy — usually clindamycin, cephalosporins, or the extended-spectrum penicillins. Clinical presentation varies from asymptomatic colonization to mild diarrhea to severe colitis. The mainstay of diagnosis is detection of C. difficile toxin A, toxin B, or both with a cytotoxin test or enzyme immunoassay of the stool of patients who have received antibiotic therapy and have features of C. difficile-associated diarrhea. Enzyme immunoassays that detect both toxins are preferred because of their higher diagnostic accuracy. If the first assay is negative and C. difficile-associated diarrhea is strongly suspected, a second assay may be performed. Ten days of oral metronidazole is the preferred therapy for most initial infections. Vancomycin is considered secondline therapy because of its cost and potential to select for vancomycin resistance. About 20% to 25% of patients experience reinfection or relapse after initial therapy and require retreatment. The disease can best be prevented by limiting the use of broad-spectrum antibiotics and adhering to control techniques.
Pediatric teledermatology: observations based on 429 consults.

Background Store-and-forward teledermatology is an emerging means of access for patients with skin disease lacking direct access to dermatologists. Objectives We sought to examine the patient demographics, diagnostic concordance, and treatment patterns in teledermatology for patients younger than 13 years. Methods We conducted a descriptive retrospective cohort study involving 429 patients. Results Diagnoses were concordant in 48% of cases, partially concordant in 10%, and discordant in 42%. Management recommendations were concordant in 28% of cases, partially concordant in 36%, and discordant in 36%. Primary care providers tended to underuse topical steroids and overuse topical antifungals and systemic antibiotics. Only 1.4% and 6.0% of patients required repeated teledermatology consultation and in-person dermatology consultation, respectively. Limitations Limitations were the inability to generalize the data from the population studied and the chances of error and bias in teledermatology diagnoses. Conclusions Store-and-forward teledermatology can improve diagnostic and therapeutic care for skin disease in children who lack direct access to dermatologists.
Conversion of a sounding rocket payload to the Shuttle/Spacelab Problems and payoffs

The Naval Research Laboratory is converting its High Resolution Telescope and Spectrograph (HRTS) sounding rocket payload for flight on Spacelab 2. The complex interfaces on Spacelab (including mechanical, thermal, electronic, computer, and pointing) have resulted in major changes to the HRTS payload and program. At present the Shuttle/ Spacelab program is not capable of accepting a sounding rocket payload essentially "as is." However, the vast increase in observing time, as well as the detailed real time interaction with a Payload Specialist, results in a substantial increase in scientific return and thus makes the conversion well worth the additional effort. Instrument Description The High Resolution Telescope and Spectrograph graph (HRTS) instrument has been designed and constructed by the Naval Research Laboratory for solar ultraviolet spectroscopy in the 1200 to 1700 angstrom region. It has been flown three times as a sounding rocket payload and is now undergoing modifications for flight on Spacelab 2. The instrument, shown in Figure 1, consists of four optical systems: a concentric Gregorian telescope, a tandem Wadsworth spectrograph, a reversed tandem Wadsworth spectroheliograph and a tandem FabryPerot H-alpha slit display system. Basic parameters of each system are given in Table 1, while the optical principles of the two spectrographs are published elsewhere. ( l~ 2, Fig. 1 The High Resolution Telescope and Spectrograph (HRTS) instrument on Spacelab 2. This paper is declared a work of the U.S. Governmentand therefore is in the public domain. Table 1. HRTS Instrument Parameters
Potentiation of antifungal activity of sesquiterpene dialdehydes against Candida albicans and two other fungi.

The antifungal activity of two drimane sesquiterpene dialdehydes, polygodial (1) and warburganal (2), alone and in combination with several other substances, was examined against three fungi,Candida albicans, Saccharomyces cerevisiae andPityrosporum ovale employing a broth dilution method. Anethole significantly synergized the activity of the two sesquiterpenoids againstC. albicans andS. cerevisiae however, it had only an, additive effect againstP. ovale. By contrast, two antioxidants, ascorbic acid (vitamin C) and BHA (butylated hydroxyanisole), noticeably enhanced the activity of the sesquiterpenoids againstP. ovale, but had no, effect againstC. albicans andS. cerevisiae.
Exploring Travel Behavior of Elderly Women in Rural and Small Urban North Dakota: An Ecological Modeling Approach

Many studies focus on the mobility patterns of elderly people. However, few studies have explored the mobility of elderly women in rural and small urban areas. Compared with their peers in large urban areas, these women tend to face greater challenges because of limited services and mobility options. Using data from 1,021 respondents to a survey conducted in North Dakota, this study examines the determinants of the travel behavior of elderly women. In particular, a multilevel conceptual ecological model was applied to identify how individual-level social environment and physical environment factors influence their travel patterns. Ordered probit models were estimated for the frequencies of nine types of trips. It was found that individual factors (e.g., self-efficacy and physical limitations), social environment factors (e.g., clubs and family), and physical environment factors (e.g., rural versus small urban areas) significantly affect the mobility of elderly women in North Dakota. The implications of these results for policies that aim to enhance the mobility of elderly women in rural and small urban locations are discussed.
Effects of thiols on escherichia coli beta-galactosidases.

IN the extensive experimentation that has involved the assay of β-galactosidase activity during the past 5 years it has been common practice to use thiols, and particularly β-mercaptoethanol. In our method of preparing this enzyme1 we use thioglycolate for the primary purpose of reducing large aggregates to a minimum. The substitution of β-mercaptoethanol in the preparative procedure, using strain ML308 as a source of β-galactosi-dase, has resulted in a variety of effects, one of which is a progressive inactivation.
Performance of flash ADCs in the 100 MHz range. I. Test bench and preliminary results

Describes a systematic study of the performance of commercially available FADCs (flash analog-to-digital converter) in the 100-megasample/s range, which might be suitable for use at the Superconducting Super Collider. Performance characteristics are measured using a CAMAC-based test bench. Among the FADC performance characteristics reported are linearity, differential linearity, and the effective number of bits. >
Hartree-Slater calculation of the cross section for L-shell ionization of argon by simple heavy charged particles

The cross sections for $L$-shell and subshell ionization by direct Coulomb excitation of argon by incident heavy charged particles are evaluated. Incident particles are described in the plane-wave Born approximation, and nonrelativistic Hartree-Slater (HS) wave functions are used for the atomic electrons. Form factors, energy distributions, and ionization cross sections are compared with those obtained from screened hydrogenic wave functions. At most incident energies the HS results for the total ionization cross section are only slightly smaller than those obtained with screened hydrogenic wave functions, but considerable discrepancies are found for form factors and energy distributions near the ionization threshold.
Macromolecular crowding remodels the energy landscape of a protein by favoring a more compact unfolded state.

The interior of cells is highly crowded with macromolecules, which impacts all physiological processes. To explore how macromolecular crowding may influence cellular protein folding, we interrogated the folding landscape of a model β-rich protein, cellular retinoic acid-binding protein I (CRABP I), in the presence of an inert crowding agent (Ficoll 70). Urea titrations revealed a crowding-induced change in the water-accessible polar amide surface of its denatured state, based on an observed ca. 15% decrease in the m-value (the change in unfolding free energy with respect to urea concentration), and the effect of crowding on the equilibrium stability of CRABP I was less than our experimental error (i.e., ≤1.2 kcal/mol). Consequently, we directly probed the effect of crowding on the denatured state of CRABP I by measuring side chain accessibility using iodide quenching of tryptophan fluorescence and chemical modification of cysteines. We observed that the urea-denatured state is more compact under crowded conditions, and the observed extent of reduction of the m value by crowding agent is fully consistent with the extent of reduction of the accessibility of the Trp and Cys probes, suggesting a random and nonspecific compaction of the unfolded state. The thermodynamic consequences of crowding-induced compaction are discussed. In addition, over a wide range of Ficoll concentration, crowding significantly retarded the unfolding kinetics of CRABP I without influencing the urea dependence of the unfolding rate, arguing for no appreciable change in the nature of the transition state. Our results demonstrate how macromolecular crowding may influence protein folding by effects both on the unfolded state ensemble and on unfolding kinetics. (end of abstract)
Measurement of the streaming potential and streaming current near a rotating disk to determine its zeta potential.

Methodology for determining the zeta potential of a disk-shaped sample by both streaming potential and streaming current measurements is presented. Integration of Laplace's equation within one radius of the disk surface revealed that the streaming potential decreased strongly in the surface normal direction. With this solution, the zeta potential can be calculated from measurements of the streaming potential near the surface of the disk provided the position of the working electrode near the disk surface is known. Determining the zeta potential of a disk-shaped sample by means of streaming current measurements required determination of a current collection efficiency because not all the streaming current from a disk flows through the auxiliary electronic current path. While the working electrode near the disk should be pointlike, several possible variants on counter electrode shape and size were explored. Although the current collection efficiency was only a few percent in each case, the measured current ...
Uniformity results of the multilayer mirrors used in the ALEXIS ultrasoft x-ray telescopes

The Array of Low Energy X-ray Imaging Sensors (ALEXIS) experiment, a mini-satellite containing six wide angle EUV/ultrasoft X-ray telescopes, is scheduled to be launched by a Pegasus rocket into a 425 nautical mile orbit in 1992 to observe cosmic X-rays. The telescopes utilize near normal incidence optics featuring a 12.8 cm diameter, 13.52 cm radius of curvature spherical mirror with a Mo/Si multilayer coating. The multilayer coatings are tuned to wavelengths of 133, 171, and 186 A. In addition, the top layers are comprised of a unique 'wavetrap' designed to suppress the dominate background radiation at 304 A from the geocorona. We present measured performance data for these mirrors including the two dimensional uniformity of the multilayer as a function of both radius and angular rotation, the measured reflectivity at the primary wavelength and the effectiveness of the 'wavetrap'. We also discuss problems encountered due to contamination and design changes that have been made to mitigate the effect of contamination.
An Interpretive Assessment of Engineering Science Core Courses

This paper provides a mapping of common conceptual difficulties in learning fundamentals of engineering analysis from two different core courses in mechanical engineering—fluid mechanics and statics. For analysis, examples from actual test questions and student performance on them are presented with interpretations of the subject areas and source of difficulties. Properly designed multiple choice questions can provide an effective evaluation of student comprehension. The paper discusses the structure of good questions, and describes how improperly designed questions may hinder learning and accurate assessment.Copyright © 2009 by ASME
Influence of Race or Ethnicity on Pharmacokinetics of Drugs

Review of the current literature on racial differences in pharmacokinetics of drugs supports the premise that only pharmacokinetic processes which are biologically or biochemically mediated have the potential to exhibit differences between racial or ethnic groups. Thus, the pharmacokinetic factors which can be expected to potentially exhibit racial differences are (1) bioavailability for drugs which undergo gut or hepatic first-pass metabolism, (2) protein binding, (3) volume of distribution, (4) hepatic metabolism, and (5) renal tubular secretion. Absorption (unless active), filtration at the glomerulus, and passive tubular reabsorption would not be expected to exhibit racial differences. As is evident from this review, there are relatively few drugs for which there is information on ethnic or racial differences in pharmacokinetics. Thus it is often necessary to try to predict whether such differences might exist. Taking into consideration the above factors and evaluation of the pharmacokinetic characteristics of the drug, it should be possible to identify those drugs most likely to exhibit differences in their pharmacokinetics. For example, a drug which is eliminated entirely by the kidneys through filtration and reabsorption and is not highly bound to plasma proteins (or is bound to albumin) is highly unlikely to exhibit racial differences in its kinetics. Conversely, a drug which undergoes significant gut and/or hepatic first-pass metabolism and is highly bound to AGP is much more likely to exhibit kinetic differences between racial groups. A discussion of the impact of racial differences in kinetics on drug response or racial differences in drug efficacy, toxicity, or pharmacodynamics (concentration-response relationship) is beyond the scope of this review. However, a number of the papers described above also evaluated differences in pharmacodynamics or response. Among the comparisons of Chinese and Caucasians, these include the papers on propranolol, morphine, nifedipine, triazolam, diazepam, and omeprazole. For those studies comparing differences in blacks and Caucasians, responses or pharmacodynamics were also determined in the studies of propranolol, trimazosin, and methylprednisolone. Interested readers are also referred to the review by Wood and a more recent review by Kitler for additional discussion of ethnic/racial differences in pharmacodynamics/drug response.
Molecular dynamics investigation of nanoscale cavitation dynamics

We use molecular dynamics simulations to investigate the cavitation dynamics around intensely heated solid nanoparticles immersed in a model Lennard-Jones fluid. Specifically, we study the temporal evolution of vapor nanobubbles that form around the solid nanoparticles heated over ps time scale and provide a detail description of the following vapor formation and collapse. For 8 nm diameter nanoparticles we observe the formation of vapor bubbles when the liquid temperature 0.5–1 nm away from the nanoparticle surface reaches ∼90% of the critical temperature, which is consistent with the onset of spinodal decomposition. The peak heat flux from the hot solid to the surrounding liquid at the bubble formation threshold is ∼20 times higher than the corresponding steady state critical heat flux. Detailed analysis of the bubble dynamics indicates adiabatic formation followed by an isothermal final stage of growth and isothermal collapse.
Bone Carbonate and the Ca to P Molar Ratio

IT is customary to consider the bone salt either as hydroxy-apatite or as tribasic calcium phosphate, principally on the basis of stoichiometric and X-ray diffraction studies1. Nonetheless, the observed molar ratio of Ca/P in the bone salt in most vertebrates is quite variable, and is usually in excess of 1.67, which is the ratio one would expect for hydroxyapatite2–4. Few studies deal directly with this discrepancy, and its dependence on the calcium carbonate content of bone has not been clearly demonstrated.