cssi/SciSciGPT-SciSciNet huggingface dataset:
A practical approach to assess the hazardous exposure potential of investigational drugs.

PURPOSE A method to evaluate the hazardous exposure potential of investigational drugs was developed in order to comply with hazardous drug handling standards. SUMMARY New nationwide standards require health-system pharmacies to recognize potential occupational risks and protect employees from any hazardous exposure. United States Pharmacopeia general chapter 800 (USP ) provides recommendations on handling precautions for commercial hazardous drugs. Recommendations for investigational drugs are less clear, with USP suggesting more widespread protections when information is deemed insufficient to assess the risk. The investigational drug services pharmacy at a freestanding pediatric hospital developed a method to evaluate the hazardous potential of investigational drugs in order to determine the likelihood that a drug held an occupational handling risk. The goal of the project was to ensure compliance with hazardous drug handling standards and provide adequate employee protection while minimizing the financial burden on the health-system pharmacy. CONCLUSION Investigational drugs that meet any of 4 defined criteria should be subject to hazardous drug handling precautions until adequate safety data are available.
Weathering the Storm: Managing Older Adults with Breast Cancer Amid COVID-19 and Beyond.

Caring for older patients with breast cancer presents unique clinical considerations due to preexisting and competing comorbidity, the potential for treatment-related toxicity, and the consequent impact on functional status. In the context of the COVID-19 pandemic, treatment decision-making for older patients is especially challenging and encourages us to re-focus our treatment priorities. While we work to avoid treatment delays and maintain therapeutic benefit, we also need to minimize the risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposures, myelosuppression, general chemotherapy toxicity, and functional decline. Herein, we propose multidisciplinary care considerations for the aging patient with breast cancer, with the goal to promote a team-based, multidisciplinary treatment approach during the COVID-19 pandemic and beyond. These considerations remain relevant as we navigate the 'new normal' for the approximately 30% of breast cancer patients age ≥70 years who are diagnosed in the U.S. annually and for the thousands of older patients living with recurrent and/or metastatic disease.
Xenophobia in the time of pandemic: othering, anti-Asian attitudes, and COVID-19

As the number of COVID-19 cases rose in the US and around the world in early 2020, conservative elites in the US racialized the pandemic, referring to the coronavirus as the “Chinese flu” or the “W...
Outcomes of Polyvinyl Alcohol Hydrogel Implant of the Lesser Metatarsals

Background:Lesser toe metatarsophalangeal (MTP) joint pathology presents a challenge for surgical treatment. At our institution, arthroplasty using a polyvinyl alcohol (PVA) hydrogel implant has be...
Management of the Acute Thrombus-Bearing IVC Filter

While anticoagulation is the mainstay for the treatment of venous thromboembolism (VTE), for patients who have failed or cannot tolerate anticoagulation therapy, caval filtration is an effective means for decreasing the risk of pulmonary embolism (PE). The first intracaval prosthesis was described by Mobin-Uddin et al. and obviated the need for open surgical caval ligation; however, this technique was plagued by thrombotic occlusion of the inferior vena cava (IVC) in the majority of patients [1]. Since then, rheologic refinements in percutaneous caval filter designs, aimed at maintaining caval flow, have mitigated—though not eliminated—the risks of caval thrombosis.
Development of Biodegradable Polymeric Nanoparticles for Systemic Delivery

In the previous chapter, the possible use of prodrug design in the enhancement of systemic delivery has been discussed. As the technique applicable to one drug may not be generalized to another drug, such an approach is comparatively labor intensive, and requires the structure of the agent designed to be manipulated case by case. As an alternative to, or as a complementary strategy for prodrug design, extensive efforts have been devoted to the development of diverse types of carriers over the last several decades. These carriers on one hand enable the delivery of multiple chemical entities and on the other hand allow for functionalization to enhance versatility and working performance. Due to their high structural flexibility, polymers have emerged as one of the most extensively studied materials for fabrication of such carriers. In this chapter, we will discuss different approaches to prepare polymeric particulates and will highlight the parameters to be characterized for optimal delivery performance in systemic delivery.
COVID-19 Impact in Neurosurgery Residency: Grit During Pandemic.

BACKGROUND: The coronavirus disease-19 (COVID) pandemic has presented a significant challenge to health care providers. Neurosurgical patients are often critically ill and at particularly high risk for COVID, and the pandemic has produced ever-shifting circumstances to allow their continued care. This study explores the psychologic impact of the pandemic on neurosurgical residents at a single institution. METHODS: Residents completed the Perceived Stress Scale (PSS) and the Inventory of Depressive Symptomology 30 (IDS-30), two validated surveys, before and during the pandemic. PSS scores range from 0 to 40 with higher scores indicative of increased stress. IDS-30 ranges from 0 to 84 with higher scores indicating more severe levels of depression. Survey results were compared collectively among residents and statistically analyzed. RESULTS: The surveys had 19 out of 28 total responders (68%). Mean score on the PSS was 16.1 prepandemic and 14.7 during the pandemic (P > 0.05). The mean score on the IDS-30 was 14.7 prepandemic and 12.0 during the pandemic (P > 0.05). Matching the survey questionnaire results by each resident revealed an average decrease of 2.3 and 2.4 for the PSS and IDS-30, respectively. CONCLUSIONS: There were no significant changes in perceived stress or depressive symptoms among neurosurgical residents during the pandemic.
And She Was Happy

Sister has learned how to walk around dry eyed. She's picked up the knack. Here she comes across the field on a swollen ankle. Sprained it running too fast around a corner. She goes down to the stream, puts the ankle in the cold water. She can hear the cows in the barn? their wet voices pooling in the trees around her; water with its tongue at her ankle, that chilled bone, and she's happy listening to the spring breeze in some slightly budded trees, enough green in them to keep them from clicking. She keeps her eyes open and her mouth shut. She's all business. When the horse threw her, knocked her out, she woke up, saw the horse's broad belly above her, and she was happy. Horse could have galloped home, but stayed. She stood up, looked into the horse's eyes, saw herself upside down and out of shape. Certain she saw remorse in the horse's brown eye, she was happy, and the world she thought was full of mercy.
Feminist Interpretations of Intellectual Property

I. Feminist Epistemology and the Construction of Knowledge.........434 A. Early Feminist Theory and the Social Construction of Knowledge 435 B. Feminist Epistemologies and Seeking Alternatives 438 II. Women as Authors, Women as Texts 447 Conclusion—Where Does Feminism Fit In? 459
Amino Acid Transport by Isolated Mammalian Renal Tubules II. TRANSPORT SYSTEMS FOR l-PROLINE

Abstract Transport of l-proline was studied in rabbit renal tubule segments prepared by collagenase digestion. A distinct two-limbed curve found when studying the effects of substrate concentration on transport velocity indicated the presence of at least two transport systems for proline. These systems could not be distinguished by their response to metabolic inhibitors or by changes in medium sodium concentration. The use of alanine and glycine as competitive inhibitors allowed the separation and identification of three kinetically distinct transport systems for proline. The transport system shared by the imino acids and glycine was shown to have a much greater affinity and a much smaller capacity for proline than for glycine. The relevance of this analysis to the investigation of human proline transport mutants is discussed.
The Theory of Legal Cynicism and Sunni Insurgency in Post-Invasion Iraq

Arab Sunni attacks and casualties in post-invasion Iraq are poorly explained by static ethnic, religious, or sectarian values involving the acceptability of violence. Alternatively, we elaborate a cultural framing theory of legal cynicism previously used to account for neighborhood variation in Chicago homicides: legal cynicism theory has an unrecognized power to explain collective and interpersonal violence in international as well as American settings. We expand on how “double and linked” roles of state and non-state actors can be used with this theory to analyze the consequences of unnecessary attacks on Arab Sunni civilians by U.S.-led forces and by Iraq military and police forces. Arab Sunnis responded to attacks with a legally cynical cultural framing of the U.S./Coalition invasion and occupation, the new Shia-dominated Iraq state, and its military and police. This post-invasion frame amplification of beliefs about state-based illegitimacy, unresponsiveness, and insecurity made it not only possible but predictable that Arab Sunni insurgent attacks would continue against U.S./Coalition forces and transfer to Shia-dominated Iraq government forces. Thus, violence in Iraq persisted during and despite Surge and Awakening efforts to end the Arab Sunni insurgency.
Dynamics of uptake of estrogens and androgens by human endometrium. Application of a double isotope perfusion technique.

Abstract Perfusion of tissue with a medium containing two metabolically related compounds, each labeled with a different isotope, and measurement of isotopic concentrations at the steady state were used to calculate the rates at which the perfused tracers enter and leave the tissue. This novel experimental design was applied to the study of the dynamics of uptake of estrogens and androgens by human endometrium. Endometrial curettings were sliced and perfused with a buffer solution containing a mixture of 3H-17β-estradiol, 14C-estrone, 3H-testosterone and 14C-4-androstene-3,17-dione. An isotopic steady state was achieved while the tissue maintained its viability. Extensive interconversion between estrone and estradiol, and between testosterone and androstenedione, was observed. The fraction of a perfused tracer that entered the tissue slices was not affected by its concentration in the range tested and was practically equal for estrone, estradiol, testosterone, and androstenedione, when perfused as a mixture. It was, however, reduced when plasma was used instead of buffer solution. More than one-half of estrone (or androstenedione) entering the tissue was released back into the medium. Only a small fraction of estradiol (or testosterone) that entered the slices was discharged into the medium; it left the tissue mainly as estrone (or androstenedione). It was estimated that the fraction of the tracer present in the tissue in a diffusible form was about 20% for androstenedione, 5% for estrone, and less than 1% for estradiol and testosterone.
A continuous space and time representation of dynamic road traffic flows consistent with hydrodynamic traffic theory

We present an approach to solving the dynamic network loading problem (DNLP). The approach views the roadway in terms of the underlying densities, segmenting the roadway into blocks of constant density. Using hydrodynamic theory, we describe how these blocks can be used to provide a solution method to the DNLP with a continuous representation of space and time which is readily implementable. This solution method provides an exact solution with piece-wise linear link travel times. We present a pseudocode description of the algorithm and discuss a sample computer implementation.
Sperm Survival at Estimated Ovulation Time: Prognostic Significance

In a group of 25 infertile couples the wives were asked to report daily for vaginal smears for evaluation of timing of ovulation. Basal body temperature was also recorded. Artificial insemination was performed or coitus was recommended to take place during estimated time of ovulation. 150 examinations of cervical secretions were made daily for 7 days from 1 1/2 hours to 72 hours after insemination. Data on 1) amount and consistency of cervical mucus; 2) number of pus cells and spermatozoa and 3) grade of sperm motility were analyzed from standpoint of timing of ovulation; effect of drugs (stilbestrol sulfonamides and hyaluronidase) and; prognostic significance of sperm survival. Spermatozoa survived routinely in the cervical mucus at ovulation time from 1 1/2 to 72 hours post-insemination (average 22 hours; mode 24 hours). There was a direct relationship between increased quantity and diminished viscosity of cervical secretions and prolonged sperm survival. Survival time of spermatozoa in the mucus is improved by the administration of estrogens but not by hyaluronidase. Where cervicitis exists sulfonamides serve to increase sperm survival. In the absence of estrogen therapy sperm survival for 24 hours or more in the cervical mucus signals ovulation time. Nevertheless optimal sperm survival in cervical mucus does not guarantee pregnancy.
Interleukin 12 and tumor necrosis factor alpha are costimulators of interferon gamma production by natural killer cells in severe combined immunodeficiency mice with listeriosis, and interleukin 10 is a physiologic antagonist.

Abstract Listeriosis in mice with the severe combined immunodeficiency (SCID) mutation is an established model in vivo and in vitro of interferon gamma (IFN-gamma)-dependent macrophage activation by natural killer (NK) cells during the development of natural immunity. We demonstrate that IFN-gamma production from SCID splenocytes is stimulated by interleukin (IL) 12, tumor necrosis factor alpha (TNF-alpha), and IL-2 but is inhibited by IL-10, IL-10, IL-12, and TNF are induced by heat-killed Listeria monocytogenes (hk-LM) from SCID splenocytes and peritoneal macrophages. IL-12 production is necessary for hk-LM to stimulate IFN-gamma production by SCID splenocytes since neutralization of IL-12 totally blocks IFN-gamma production in this system. TNF-alpha and IL-2 act synergistically with IL-12 to augment IFN-gamma production. Also, exogenous IL-2 increases the response of NK cells to hk-LM or to IL-12 and TNF-alpha. In contrast, IL-10 inhibits hk-LM-induced IFN-gamma production at two levels: (i) by inhibiting TNF and IL-12 production from these cultures (presumably from the macrophage) and (ii) by inhibiting the stimulatory effects of IL-12 and TNF-alpha on NK-cell IFN-gamma production. Thus, these data indicate that macrophage production of TNF-alpha and IL-12 stimulates the release of IFN-gamma by NK cells and that IL-10 produced in response to hk-LM inhibits this response at the level of the macrophage and the NK cell.
Introducing technology to educators in a way that is compelling—not intimidating: support issues

Introducing technology to educators in an education-centered way requires dedicated and specialized staff, workspace and equipment.
The determination of sulfur, lead, and silicon in atmospheric aerosols: an application of X-ray fluorescence and confined-spot paper techniques.

An X-ray fluorescence-confined spot technique has been developed and used for the determination of sulfur in compounds from air samples collected on small membrane filters and for lead and silicon in compounds from air samples collected on paper tape. On 100-mm2 spots, the minimum detectable limit for sulfur is 0.15μg, for lead and silicon it is 0.4μg. The technique is simple, precise, and rapid and should be applicable to the determination of elements above atomic number 12.
Light-induced changes of bound chloroplast plastocyanin as studied by EPR spectroscopy: the role of plastocyanin in noncyclic photosynthetic electron transport.

Abstract A low-temperature electron paramagnetic resonance (EPR) signal in spinach chloroplasts has been identified as originating from oxidized bound plastocyanin. The EPR parameters of the bound plastocyanin, which are the same as those of soluble plastocyanin, are: g ⊥ = 2.05, g ∥ = 2.23, and A ∥ = 0.006 cm −1 . An estimation of the amount of bound plastocyanin based on the in situ EPR signal indicates a concentration of approximately 3 nmoles per mg chlorophyll, a value which agrees with the amount of plastocyanin determined by chemical assay after release from the chloroplast lamellae by sonication. Light-induced changes of plastocyanin in situ have been examined after illumination with monochromatic light at physiological temperatures. The bound plastocyanin undergoes a photoreduction in Photosystem II light which is sensitive to inhibitors of noncyclic electron transport. The presence of the NADP + acceptor system in Photosystem II light causes a shift in the steady-state level of plastocyanin providing direct evidence for the role of plastocyanin in noncyclic electron transport from water to NADP + . Phosphorylation cofactors and the uncoupler, NH 4 Cl, also cause shifts in the plastocyanin steady-state level in red light. Photosystem I light is able to photooxidize reduced plastocyanin, while Photosystem II light is only capable of photooxidation in the presence of inhibitors of the photoreduction. These results of studies on plastocyanin photoreactions in situ are discussed in terms of different proposed roles for plastocyanin in the chloroplast noncyclic electron transport chain.
Seismic and ultrasonic data analysis for characterizing people and animals

In this paper we analyze the seismic signals generated by people and animals walking. It is known that when a person walks, the heel strikes first and then the front of the foot; whereas animals walk on their hoofs. This difference in the walking patterns result in significant changes in the seismic signatures for both people and animals. Similarly, men walk differently than women and they also have different weight distributions resulting in different signatures for men and women. They also have different cadence or gait patterns. We distinguish the significant features in seismic signatures to distinguish people and animals. Ultrasonic Doppler returns capture the variations in the gait. The Doppler returns will be analyzed to distinguish people and animals. Algorithms to classify the signatures will be provided. The algorithms will be tested on the data collected at a horse farm with women, men and people walking. The results will be discussed along with possible future research directions to reduce the number of false alarms.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Prenatal Hormone Treatment with Thyrotropin Releasing Hormone and with Thyrotropin Releasing Hormone Plus Dexamethasone Delays Antioxidant Enzyme Maturation but Does Not Inhibit a Protective Antioxidant Enzyme Response to Hyperoxia in Newborn Rat Lung

ABSTRACT: Whereas glucocorticoid administration to pregnant rats produces parallel acceleration of lung surfactant and antioxidant enzyme system maturation in late gestation, prenatal thyroid hormone treatment results in acceleration of surfactant maturation, with a paradoxical decrease in antioxidant enzyme (AOE) development. In these studies, we tested whether prenatal thyroid releasing hormone (TRH) treatment would act like prenatal thyroid hormone on pulmonary surfactant and AOE system maturation and whether combined prenatal treatment with TRH plus dexamethasone (DEX) would alter these effects. Secondly, we tested whether prenatal TRH and prenatal TRH plus DEX would inhibit the ability of newborn rats to respond to hyperoxia with protective increases in AOE activities. Results of the developmental studies revealed significantly increased fetal lung disaturated phosphatidylcholine content with significantly decreased pulmonary AOE activities as a result of prenatal TRH treatment that was not reversed with the addition of DEX. Combined TRH plus DEX treatment resulted in statistically significant decreases in body weight, lung weight, and lung weight to body weight ratios at both 21 and 22 d of gestation; growth effects were not seen with TRH alone. In tenns of hyperoxic AOE response, despite being born with lower baseline AOE levels, the newborn animals prenatally treated with TRH or TRH plus DEX were able to induce a normal pulmonary AOE response to high O2 exposure. Although requiring further investigation, this reassuring finding suggests that clinical prenatal therapy with TRH or the combination of TRH plus DEX is not contraindicated for those infants delivered prematurely who go on to require intensive hyperoxic therapy.
Trophic relationships among concentrated populations of small fishes in seagrass meadows

Abstract Changes in available food and utilized foods for a densely populated guild of animals can uncover periods of niche displacement among particular consumer species or their separate size classes. Dense populations of small fishes and their foods were censussed for 13 months and studied experimentally in shoalgrass and turtlegrass meadows of Redfish Bay, Texas. Feeding habits were determined with respect to prey availability, and illustrated the extent to which seasonal partitioning of food corresponded to food depletion among these abundant consumers in seagrass meadow food webs. The darter goby, code goby, pinfish, and Gulf pipefish were the most common species throughout the year. Although the darter goby did not show distinct ontogenetic changes in food habits, the code goby, Gulf pipefish, and pinfish demonstrated major ontogenetic progressions of foods selected. Food availability in the seagrass meadows changed seasonally. When major prey such as amphipods were abundant, during spring, many fish species showed high overlap in food use. Regardless of food availability, the code goby and Gulf pipefish fed mainly on amphipods or copepods. The more common darter goby and pinfish seasonally changed their diets with changes in food availability; the darter goby and pinfish were more carnivorous during spring, but they largely consumed epiphytic algae during summer. Cage experiments were used to monitor foods confined with elevated densities of pinfish and darter gobies, relative to control cages at natural overall densities. Prey items in the former cages decreased sharply, with corresponding dietary shifts by these common fishes. During resource depletion, these changes in resource use by these naturally concentrated consumers appeared as temporary partitioning of available resources. This shift occurred during both natural (seasonal) and experimental depletions of food, and appears to result from increased interspecific and intraspecific competition during periods of depleted preferred foods.
Live imaging of bulk endocytosis in frog motor nerve terminals using FM dyes

We observed endocytosis in real time in stimulated frog motor nerve terminals by imaging the growth of large membrane infoldings labeled with a low concentration of FM dye. The spatial and temporal information made available by these experiments allowed us to image several new aspects of this synaptic vesicle recycling pathway. Membrane infoldings appeared near synaptic vesicle clusters and grew rapidly during long-duration, high-frequency stimulation. In some cases, we observed large, elongated infoldings growing laterally into the terminal. We used these observations to calculate infolding growth rates. A decrease in stimulation frequency caused a decrease in growth rates, but the overall length of these structures was unaffected by frequency changes. Attempts to wash the dye from these infoldings after stimulation were unsuccessful, demonstrating that the fluorescent structures had been endocytosed. We also used this technique to trigger and image infoldings during repeated, short trains. We found that membrane uptake occurred repeatedly at individual endocytosis sites, but only during a portion of the total number of trains delivered to the terminal. Finally, we showed that phosphatidylinositol 3-kinase, but not actin, was involved in this endocytosis pathway. The ability to monitor many individual bulk endocytosis sites in real time should allow for new types of endocytosis measurements and could reveal novel and unexpected mechanisms for coordinating membrane recovery during synaptic activity.
New editor for a quality journal.

Starting with the third issue of 2004, I will have the pleasure and the honour of taking over the editorial responsibility for the International Journal for Quality in Health Care . In fact, those of you who have submitted papers recently to the Journal may have noticed that manuscript assessments have been handled by the new editorial office as of December 2003, when the Journal’s online submission system became operational. Let me begin by thanking the International Society for Quality in Health Care (ISQua) for entrusting me with its scientific journal, and Dr Heather Palmer, who has edited this journal for the past ten years, for handing over a superb vessel for the scientific ideas of researchers worldwide who strive to improve health care. The handover of the editorial responsibilities was made particularly pleasurable by the joint efforts of Dr Palmer, Ms Morag Teek, the current managing editor, Mrs Lee Tregloan, Chief Executive Officer of ISQua, Dr David Ballard, ISQua board member in charge of publications, MrsMandy Hill, editor at Oxford University Press, and all members of the Journal’s Editorial Committee. I am currently head of the Quality of Care Unit at Geneva University Hospitals, and professor of health services evaluation at the Faculty of Medicine, University of Geneva (Switzerland). Rather than going into unnecessary detail of my past or current work, I will submit here my Top Five achievements, related to the role of editor of the Journal . 1. I know a lot about poor quality in clinical care, in good measure through acts of …
Genetic Analysis of Mobile tetQ Elements in Oral Prevotella Species

Prevotella species are members of the bacterial oral flora and are opportunistic pathogens in polymicrobial infections of soft tissues. Antibiotic resistance to tetracyclines is common in these bacteria, and the gene encoding this resistance has been previously identified as tetQ. The tetQ gene is also found on conjugative transposons in the intestinal Bacteroides species; whether these related bacteria have transmitted tetQ to Prevotella is unknown. In this study, we describe our genetic analysis of mobile tetQ elements in oral Prevotella species. Our results indicate that the mobile elements encoding tetQ in oral species are distinct from those found in the Bacteroides. The intestinal bacteria may act as a reservoir for the tetQ gene, but Prevotella has incorporated this gene into an IS21-family transposon. This transposon is present in Prevotella species from more than one geographical location, implying that the mechanism of tetQ spread between oral Prevotella species is highly conserved.
Harnessing database resources for understanding the profile of chemical process industry incidents

Analyzing historical databases can provide valuable information on the incident occurrences and their consequences for assessing the safety of the chemical process industry. In this study, the RMP and HSEES databases were utilized to understand the patterns and the factors influencing chemical process industry incidents. Frequency exceedance curves were generated by utilizing the different incident consequences from the databases to understand the profile of societal loss from reported incidents. Understanding the statistics and trends of the historical incidents could serve as important lagging indicators in order to assess the probable proximity to major consequences from the low-probability/high-consequence incidents. To this regard, the safety pyramids were also generated to better understand the relationship between the different consequences of the reported incidents. Furthermore, the safety pyramids were analyzed in comparison with the traditional safety pyramid proposed by Heinrich to understand the US process industry incident occurrence trends.
Simulating magnetic positive positioning of cryogenic propellants in a transient acceleration field

A computational simulation of magnetic positive positioning (MP2) is developed to model cryogenic propellant reorientation in reduced gravity. Previous efforts have successfully incorporated an electromagnetic field model into an axisymmetric, two-dimensional, incompressible fluid flow model yielding accurate predictions of fluid motion induced by a magnetic field. To simulate MP2, a three-dimensional magnetic field and magnetic force model was developed as a feature of a commercially available fluid flow model which has been well validated. The computational tool was then improved upon to model magnetically induced flows in a transient acceleration field. Simulation predictions obtained with the enhanced model are compared to available reduced gravity experiment data. Evidence is presented and conclusions are drawn that support the continued use of the simulation as viable modeling and predictive tool in the continuing study of MP2.
Simulation of charge motion in ball mills. Part 1: experimental verifications

Abstract A numerical tool known as the discrete element method (DEM) is used to study the motion of the ball charge in ball mills. In particular, the motion of individual balls in the ball charge is simulated. An interesting aspect of this simulation is that it yields the frequency distribution of ball collisions as a function of collision energy. The results of numerical simulations are compared with experiments: The angular positions of the toe and shoulder, the trajectory of two balls, and the power draft — all of these predictions are reasonably close to experimental measurements. An interesting sidelight of this study is that the collision frequency can be combined with the breakage property of particles to carry out direct simulation of particle fragmentation in ball mills. The rudiments of such a simulation are illustrated.
Evaluation of Competence in the Interpretation of Chest Radiographs

Abstract Rationale and Objectives The purpose of this study was to determine relative rates of missed diagnoses for radiologists as a measure of competence in interpreting chest radiographs. Materials and Methods Cases involving differing interpretations of chest radiographs were collected from January 1994 through December 1999 by faculty (chest and nonchest radiology specialists) in an academic radiology department. A quarterly peer-review process designated cases months after the fact, and anonymously, as no miss or as class I (nondiagnosable), class II (very difficult diagnosis), class III (should be diagnosed most of time), or class IV (should almost always be diagnosed) missed diagnoses. The rates and classes of missed diagnoses were compared among chest faculty and for the nonchest radiology specialists as a group. Results Chest radiologists read 184,977 studies, and nonchest radiologists read 300,684 studies. Of these, 243 missed diagnoses were classified (classes I and II, 184 cases; class III, 50; and class IV, nine). No difference was detected in the rate of class III and IV misses among chest faculty, but nonchest faculty had significantly more class III ( P = .022) and class IV misses ( P = .016). Conclusion Random sampling of differing interpretations can yield a relative rate of missed diagnoses for radiologists. No difference was detected in clinically important misses (ie, classes III and IV) among chest radiologists, but a statistically significantly higher rate of seemingly obvious misdiagnoses was found for nonchest specialty radiologists. Potential biases may have influenced this analysis, including disease prevalence, sampling, clinical factors, observer variability, and truth-in-diagnosis.
A decoupled design in distributed control of uncertain networked control systems

This paper studies interconnected networked control systems in the presence of communication constraints and uncertainties. We propose a novel control architecture for subsystems that can decouple the design of output-feedback control strategy and the communication scheme. In this architecture, a navigator serves as the bridge between the uncertain, communication-limited system and an ideal model that has perfect communication and no uncertainties. Under this framework, one can integrate the existing communication protocols and robust control techniques into this architecture without worrying for the coupling between the control and the communication. We provide stability condition for the resulting closed-loop system and derive bounds on the error signals between the real system, the navigator and the ideal model. It is shown that these bounds can be arbitrarily reduced by improving the communication condition and tuning the low-pass filter in the controller. The results can significantly improve the predictability of the behavior of uncertain systems, which is important for safety-critical applications.
Prescription Analgesic and Antidepressant Utilization and Cost Among Elderly Medicaid Beneficiaries Before and After Nursing Home Admission

Objectives The objectives of this study were to describe changes in prescription analgesic and antidepressant medications and to track the costs associated with these medication changes when elderly Medicaid beneficiaries move from the community to a nursing home setting. Design Retrospective analysis of Medicaid long-term care and drugs claims data for fiscal year 2000 from three different states. Setting Long-term care facilities in three different states. Participants We studied 1321 elderly Medicaid beneficiaries newly admitted to a nursing home during the study period. Measurements Pain medications were grouped into four different categories and all antidepressants were grouped into one category. For each medication category, we obtained the number of unique patients for whom it was prescribed, the number of days it was prescribed, and the amount paid by Medicaid. We then calculated the percentage of subjects prescribed and the amount paid per day for each medication class before and after nursing home admission. Results Except for skeletal muscle relaxants, 21% to 39% of beneficiaries already had claims linked to each medication class while still living in the community. After nursing home admission, the percentage of beneficiaries exposed to each medication class increased by 2% to 33%. Cost per day of therapy increased by 10% to 83%. There was significant variation among the states in utilization and cost per day of therapy. Conclusions We draw three major conclusions: (1) community-dwelling elderly Medicaid beneficiaries in this study use more prescription analgesics and antidepressants than community-dwelling elders in prior studies; (2) there is a significant increase in medication utilization and cost on nursing home admission; and (3) significant variability in medication use and cost exists among the three states examined. Further investigation to elucidate the reasons for these differences could assist legislators in formulating sound public policy to contain Medicaid expenditures without sacrificing patient care.
Synthesis and characterization of a series of macrocyclic chelates containing O and N donors: Prospects for use as NMR shift agents for alkali-metal cations

A new series of polyoxa tetraaza macrocyclic tetraacetates have been prepared and characterized. These derivatives chelate lanthanides and transition-metal ions in the tetraaza tetraacetate portion of the macrocycle, leaving the polyoxa portion available for binding with alkali-metal cations. The protonation constants and metal-binding properties of these chelates have been investigated and compared to those of the parent molecule 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). The Dy 3+ , Ni 2+ , and Co 2+ complexes were examined for their ability to induce a paramagnetic shift in the 23 Na + NMR resonance of aqueous NaCl at pH 7
Homodimers of the antiviral abacavir as modulators of P-glycoprotein transport in cell culture: probing tether length

A major hurdle in permanently eliminating HIV from the body is the persistence of viral reservoirs, including those of the brain. One potential strategy towards eradicating HIV reservoirs of the brain is to block efflux transporters, such as P-glycoprotein (P-gp), that contribute to the limited penetration of antiviral agents across the blood–brain barrier (BBB). Herein, we described a series of dimeric inhibitors of P-gp based on the nucleoside reverse transcriptase inhibitor and P-gp substrate, abacavir. Varying tether lengths were used to generate abacavir dimers to probe tether requirements for inhibitory potency. These dimeric agents were evaluated in two cell lines that express P-gp at varying levels: a P-gp over-expressing CD4+ T-lymphocyte cell line (12D7-MDR) and a human brain capillary endothelial cell line as an in vitro model of the BBB (hCMEC/D3) that expresses endogenous levels of P-gp. All dimeric abacavir analogs were inhibitors of P-gp efflux in the two cell lines with potencies that varied with tether length; the most potent agents displayed low micromolar inhibition. P-gp inhibition in a highly P-gp over-expressing cell line (MCF-7/DX1) was also observed with a range of therapeutic substrates. Competition studies with the photoaffinity substrate [125I]iodoarylazidoprazosin demonstrated that abacavir dimers act by competing for the substrate binding sites of P-gp. These data demonstrate that the tether length of dimeric abacavir derivatives has a significant effect on inhibition of P-gp drug efflux, with up to a 35-fold increase in potency observed with longer tether linkages.
Dynamic targeting of the agonist-stimulated m2 muscarinic acetylcholine receptor to caveolae in cardiac myocytes

In cardiac myocytes, as well as specialized conduction and pacemaker cells, agonist binding to muscarinic acetylcholine receptors (mAchRs) results in the activation of several signal transduction cascades including the endothelial isoform of nitric-oxide synthase (eNOS) expressed in these cells. Recent evidence indicates that, as in endothelial cells, eNOS in cardiac myocytes is localized to plasmalemma caveolae, specialized lipid microdomains that contain caveolin-3, a muscle-specific isoform of the scaffolding protein caveolin. In this report, using a detergent-free method for isolation of sarcolemmal caveolae from primary cultures of adult rat ventricular myocytes, we demonstrated that the muscarinic cholinergic agonist carbachol promotes the translocation of mAchR into low density gradient fractions containing most myocyte caveolin-3 and eNOS. Following isopycnic centrifugation, the different gradient fractions were exposed to the muscarinic radioligand [3H]quinuclidinyl benzilate (QNB), and binding was determined after membrane filtration or immunoprecipitation. In a direct radioligand binding assay, we found that [3H]QNB binding can be detected in caveolin-enriched fractions only when cardiac myocytes have been previously exposed to carbachol. Furthermore, most of this [3H]QNB binding can be specifically immunoprecipitated by an antibody to the m2 mAchR, indicating that the translocation of this receptor subtype is responsible for the [3H]QNB binding detected in the low density fractions. Moreover, the [3H]QNB binding could be quantitatively immunoprecipitated from the light membrane fractions with a caveolin-3 antibody (but not a control IgG1 antibody), confirming that the m2 mAchR is targeted to caveolae after carbachol treatment. Importantly, atropine, a muscarinic cholinergic antagonist, did not induce translocation of m2 mAchR to caveolae and prevented receptor translocation in response to the agonist carbachol. Thus, dynamic targeting of sarcolemmal m2 mAchR to caveolae following agonist binding may be essential to initiate specific downstream signaling cascades in these cells.
A 4-MV CT scanner for radiation therapy; spectral properties of the therapy beam

A Clinac-4 therapy accelerator has been modified to function also as a computed tomography (CT) scanner. We report on measurements made to calibrate the beam. 104 Bismuth-germanate silicon-photodiode detectors were placed in a circular arc of radius 180 cm, centered on the source, in the arrangement of a third-generation CT scanner. With the beam collimated to a fan section and just filling the detectors, the signal S(chi), obtained with thickness chi of plastic phantom, closely followed the relationship S(chi)/S(0) = exp [- (alpha chi + beta chi 2)], where coefficients alpha and beta varied systematically over the extent of the beam. This result agrees with results of similar work by others. It may be explained in terms of the spectral changes that are known to be an inherent property of such beams. Expressions relating alpha and beta to the source spectral density are derived; also estimates of the source spectral density are calculated using the method of Laplace inversion. It is shown that scattered radiation arising from the fan beam within the scattering medium does not contribute significantly to the values of alpha and beta.
Folly in Trade and Technology Policy (Comments on 'Do we need a technology policy?' by S.J. Kline and D.E. Kash)

The commenters note that S.J. Kline and D.E. Kash (ibid., vol.11, p.18-25, Summer 1992) raise a number of interesting points in their discussion of the functions of government technology policy. The commenters point out that the importance of the issues discussed by Kline and Kash is underscored by a recent tariff imposed on active-matrix liquid-crystal displays (AMLCDs). They suggest that it is important that the Kline and Kash article serve as the basis of continuing discussions within the IEEE community and other scientific and engineering communities, relative to issues of technology policy development. They conclude that perhaps the concerns expressed by Kline and Kash, and by N.W. Buckly (1992), will generate an increased level of understanding, concern, and discourse on this extremely important topic. >
Subsurface breakdown device reliability

New data from special bipolar junctions that breakdown below the Si-SiO 2 interface are described. The devices were broken down both in a dc and pulse fashion, and junction degradation in the form of increased reverse leakage and reduced minority carrier lifetime was investigated. No degradation was observed.
Adipose progenitor cells increase fibronectin matrix strain and unfolding in breast tumors

Increased stiffness represents a hallmark of breast cancer that has been attributed to the altered physicochemical properties of the extracellular matrix (ECM). However, the role of fibronectin (Fn) in modulating the composition and mechanical properties of the tumor-associated ECM remains unclear. We have utilized a combination of biochemical and physical science tools to evaluate whether paracrine signaling between breast cancer cells and adipose progenitor cells regulates Fn matrix assembly and stiffness enhancement in the tumor stroma. In particular, we utilized fluorescence resonance energy transfer imaging to map the molecular conformation and stiffness of Fn that has been assembled by 3T3-L1 preadipocytes in response to conditioned media from MDA-MB231 breast cancer cells. Our results reveal that soluble factors secreted by tumor cells promote Fn expression, unfolding, and stiffening by adipose progenitor cells and that transforming growth factor-β serves as a soluble cue underlying these changes. In vivo experiments using orthotopic co-transplantation of primary human adipose-derived stem cells and MDA-MB231 into SCID mice support the pathological relevance of our results. Insights gained by these studies advance our understanding of the role of Fn in mammary tumorigenesis and may ultimately lead to improved anti-cancer therapies.
Experimental study of multilayer adsorption on fractal surfaces in porous media

We report a nitrogen adsorption isotherm study on three shale samples that have been previously characterized by small-angle neutron scattering (SANS). The scattering data establish that the pore surfaces in these porous materials are self-similar fractals over a range of length scales between 5 and 500 \AA{}, and the fractal dimension D varies between 2.59 and 2.83. For isothermal adsorption of multilayer liquid film on fractal surfaces, the theoretical predictions are (i) the number of adsorbed molecules N increases with the vapor pressure P as $N\ensuremath{\sim}[\mathrm{ln}{(P}_{0}/P){]}^{D\ensuremath{-}3}$ and (ii) the area of the liquid-vapor interface ${S}_{I}$ decreases as ${S}_{I}\ensuremath{\sim}[\mathrm{ln}{(P}_{0}/P){]}^{D\ensuremath{-}2}.$ We find that fitting our data to these predictions results in D values that are significantly lower than the SANS results. More careful examination of the data reveals systematic deviations from the predicted power-law behaviors. We discuss the assumptions and approximations made in the theories that could have caused this discrepancy.
User-Controlled Technology in the Humanities

Humanists have resisted and sometimes actively opposed the use of instructional technology for a variety of reasons including, but not limited to, the following: 1) self-preservation, fear of being replaced by a “machine”; 2) myths associated with technology; and 3) lack of technical skills.Upon closely examining these frequently used reasons, it becomes apparent that the common link among them is the instructor's fear of somehow relinquishing control over the teaching/learning environment It would appear that, in order to be acceptable to most humanists, any new instructional technology must be user-controlled. Cases are presented in which user-controlled technology is being used successfully in literature, drama, art, music and languages.
Immunohistochemical localization of relaxin in the reproductive system of the female opossum (Didelphis virginiana).

Summary Relaxin-immunoreactivity was demonstrated in the cytoplasm in the luteal cells from pregnant and lactating opossums. Immunoreactivity for relaxin was not demonstrated elsewhere in the ovary, in the reproductive tract or in the placenta. The corpus luteum is thought to be the primary source of relaxin in Didelphis and in this regard is similar to several eutherian mammals including man.
Dependency based reasoning in a dempster-shafer theoretic framework

Bayesian networks (BNs) represent joint space probabilities compactly and enable one to carry out efficient inferencing. Although the Dempster-Shafer (DS) belief theoretic framework captures a wider class of imperfections, its utility in such graphical models is limited. This is mainly due to the requirement of having to maintain a basic probability assignment (BPA) for the whole power set of propositions of interest. In this paper, we introduce a simpler BPA that can still capture many types of imperfections that are commonly encountered in practice. This BPA is then used to develop the DS-BN, a graphical dependency model that represents the joint space belief distribution. We show how this DS-BN can efficiently carry out inferences within the DS theoretic framework. Its utility is illustrated by modeling a problem involving missing values and then comparing the inferences made with those obtained via a BN that learns its parameters using the EM algorithm.