cssi/SciSciGPT-SciSciNet huggingface dataset:
Silicone rubber RTV-1 aging in the presence of aqueous salt

In our previous research on the effect of salt on aging of Room Temperature Vulcanized one-component (RTV-1) silicone rubber material we reported a strong relationship between losses in material mass and hydrophobicity, and potentially significant changes in the mechanical properties of the materials. This is further investigated in the present study, which examines the effects of aging in aqueous salt solution at elevated temperature on the hardness, hydrophobicity, and damage of a selected high quality RTV-1 material. A simple mechanical approach is suggested, which could be used in service to evaluate the amount of aging of RTV materials by correlating changes in hardness with surface conditions such as hydrophobicity. In addition, a new model of aging of RTVs based on the formation of hypochlorous acid in the presence of saltwater on energized silicone rubber surfaces is suggested and supported by Molecular Dynamics (MD) simulations. The diffusion rates of hypochlorous acid, salt ions, water, and nitric acid were numerically compared to determine which aging compound could be primarily responsible for material damage to RTVs under both laboratory and in-service conditions.
What Is the Best Port Placement for Urologic Robotic Surgery

The use of robotics has increased in the field of urology since the beginning of the twenty-first century. Laparoscopy has emerged as an alternative to open surgery seeking to mimic its technical aspects and aiming to achieve similar functional and oncological outcomes, and offering faster recovery. The robotic platform is able to provide additional benefits and provide many additional advantages over laparoscopy, such as 3D visualization with high-definition, magnification of up to ten times providing an enhanced view of the operative field, and the EndoWrist® system which provides seven degrees of motion freedom as well as ergonomics. However, to be able to explore these features, it is quintessential that the robotic arm ports are properly placed and robot docking be properly achieved to allow for the full benefits of robotic surgery. Herein, we describe the port placement, robot docking, and the use of four robotic arms for urologic robotic surgery utilized at our institution.
Branch-locking AD techniques for nonsmooth composite functions and nonsmooth implicit functions

A recent nonsmooth vector forward mode of algorithmic differentiation (AD) computes Nesterov's L-derivatives for nonsmooth composite functions; these L-derivatives provide useful sensitivity inform...
A perspective on control system design by means of semi-infinite optimization algorithms

We present an overview of the use of semi-infinite optimization algorithms in linear, multivariable control system design. We deal with problem formulation, basics of algorithms, numerical aspects and software requirements.
Simple autocorrelation method for thoroughly characterizing single-photon detectors

We introduce and demonstrate a simple and highly sensitive method for characterizing single-photon detectors. This method is based on analyzing multi-order correlations among time-tagged detection events from a device under calibrated continuous-wave illumination. First- and second-order properties such as detection efficiency, dark count rate, afterpulse probability, dead time, and reset behavior are measured with high accuracy from a single data set, as well as higher-order properties such as higher-order afterpulse effects. While the technique is applicable to any type of click/no-click detector, we apply it to two different single-photon avalanche diodes, and we find that it reveals a heretofore unreported afterpulse effect due to detection events that occur during the device reset.
Predicting the need for home gavage or g-tube feeds in asphyxiated neonates treated with therapeutic hypothermia

Asphyxiated infants treated with therapeutic cooling can have persistent oral feeding difficulty because of involvement of neural pathways in the brainstem, cortex, and basal ganglia. The goal is to predict the composite adverse outcome of death or persistent oral feeding difficulty using precooling/cooling attributes, and the severity and distribution of hypoxic–ischemic lesions, especially brainstem lesions on post-cooling brain magnetic resonance imaging (MRI). Retrospective review of 86 asphyxiated infants cooled from January 2006 to August 2014. Persistent feeding difficulty was defined as needing feeding support (gastrostomy tube (g-tube) or home gavage feeds) after discharge. Clinical and laboratory risk factors, and the brain MRI abnormalities including the presence of brainstem lesions were compared between infants with and without adverse outcome using univariate analysis. Significant variables were then analyzed in a stepwise logistic regression (LR) model. Infants with adverse outcome (n = 31, 4 died pre-discharge) had longer hospital stay (26 days, interquartile range (IQR) 19–43 vs. 13 days, IQR 9–20; p < 0.01) and reached goal enteral feeds (oral/gavage) later (11 days vs. 8 days, p < 0.01) compared to 55 infants discharged on full oral feeds. The former infants were more likely to have cord pH ≤ 7.15, severely abnormal neurological examination, bleeding diathesis, continued need for ventilation, and positive MRI findings including brainstem lesions. In LR analysis, brainstem lesions on MRI (p = 0.00, odds ratio 19, 95% confidence interval 4–85) was independently associated with the adverse outcome. Brainstem involvement on post-cooling brain MRI was predictive of adverse outcome. Early identification of these infants may facilitate discussion of home feeding plans between clinicians and parents earlier, thereby potentially reducing the length of hospital stay.
Characteristics of defective infrastructure as code scripts in DevOps

Defects in infrastructure as code (IaC) scripts can have serious consequences for organizations who adopt DevOps. By identifying which characteristics of IaC scripts correlate with defects, we can identify anti-patterns, and help software practitioners make informed decisions on better development and maintenance of IaC scripts, and increase quality of IaC scripts. The goal of this paper is to help practitioners increase the quality of IaC scripts by identifying characteristics of IaC scripts and IaC development process that correlate with defects, and violate security and privacy objectives. We focus on characteristics of IaC scripts and IaC development that (i) correlate with IaC defects, and (ii) violate security and privacy-related objectives namely, confidentiality, availability, and integrity. For our initial studies, we mined open source version control systems from three organizations: Mozilla, Openstack, and Wikimedia, to identify the defect-related characteristics and conduct our case studies. From our empirical analysis, we identify (i) 14 IaC code and four churn characteristics that correlate with defects; and (ii) 12 process characteristics such as, frequency of changes, and ownership of IaC scripts that correlate with defects. We propose the following studies: (i) identify structural characteristics that correlate with defects; (ii) with respect to prediction performance, compare which characteristics of IaC scripts are more correlated with defects; and (iii) identify characteristics that violate security and privacy objectives.
Spinal Arachnoiditis as a Manifestation of Sarcoidosis (P06.229)

OBJECTIVE: To report an unusual presentation of sarcoidosis. BACKGROUND: Spinal arachnoiditis is caused by inflammation of the spinal cord arachnoid membrane. Typical symptoms include back pain, urinary urgency and/or incontinence, sensory loss and weakness in the lower extremities. Identified causes include infection, spinal surgery, epidural anesthesia or steroid injection and myelographic contrast materials. We report a rare case of spinal arachnoiditis as a manifestation of sarcoidosis. DESIGN/METHODS: Case report. RESULTS: A 49 year-old man with a history of “asthma” presented with chronic low back pain and urinary urgency. Exam revealed moderate weakness in bilateral foot dorsiflexion and toe extension as well as atrophy of intrinsic foot muscles. Deep tendon reflexes were reduced in the legs. MRI of the lumbar spine demonstrated thickening and clumping of nerve roots which adhered to the walls of the thecal sac. A diagnosis of spinal arachnoiditis was made. No risk factors for this condition were identified in the patient. A work up for infectious, metabolic and autoimmune etiology was negative. A spinal tap revealed slightly elevated white cell of 7 per µL (normal: 0-5) and CSF protein of 54 mg per dL (normal: 15-45). A CT chest showed aortopulmonary and hilar lymph nodes with severe consolidations and ground glass appearance in both lobes. Transbronchial biopsy revealed the presence of noncaseating granuloma with negative stains and cultures for acid fast bacilli and fungi. The patient was diagnosed with sarcoidosis. His pulmonary symptoms and CT chest appearance improved after treatment with oral corticosteroid but he continued to require pain medication for back pain. CONCLUSIONS: Spinal sarcoid is very rare, and most cases present as intramedullary lesions. This case underscores the importance of including sarcoidosis in the differential diagnosis of spinal arachnoiditis when no clear risk factor for it can be identified. Disclosure: Dr. Jiang has nothing to disclose. Dr. Tomyanovich has nothing to disclose. Dr. Flowers has nothing to disclose.
International Negotiations and State Interests: A Green Climate Fund Simulation

The simulation that we present here was designed to introduce students not only to climate change policy making but also to the Green Climate Fund and the process of negotiation. Rather than concen...
Can You Hear Me Now? Impediments to Science Communication

Imagine, if you can, that workers at CERN have begun talking to dead people, thanks to the LHC. This is the plot of Franklin Clermont’s novel The Voices at CERN. Shannon Fields, the fictional CERN senior press relations coordinator, is tasked with speaking to the concerned wife of one of the technicians. Shannon’s superiors reason that she is qualified for this task because her job entails explaining “each new discovery to the waiting news organizations that felt compelled to deliver news in 30 second sound bites only and language pegged at an eighth grade reading level or lower” [1] as well as talking to the general public about black hole fears and “that destroy-the-world stuff” [2]. Shannon is understandably concerned about the ramifications to their public image (especially on safety issues) if the employees’ claims becomes public, imagining the resulting “lurid American tabloid headlines: ‘CERN: I Hear Dead People’” [3]. While this example is clearly outlandish, the fictional headline is an excellent parody of reality. However, studies suggest that it is not the tabloids that Shannon and her real-world counterpart have to be concerned about, but rather the Internet, especially in the United States [4]. The fact-checking website Snopes.com has had to debunk several curious Internet claims about CERN, perhaps the most bizarre being a video purporting to show a ritual human sacrifice conducted on the grounds of the facility [5]. In reality it was a prank conducted without the knowledge or permission of CERN and those responsible were held accountable [6]. However, the damage has already been done, as the video is still easily found online.
Differential effects of ATP-MgCl2 on portal and hepatic arterial blood flow after hemorrhage and resuscitation.

Although ATP-MgCl2 administration after hemorrhage and resuscitation restores the decreased hepatic blood flow, it is not known whether this is due to the increase in portal blood flow or hepatic arterial blood flow. To study this, rats underwent a midline laparotomy (i.e., trauma induced) and were bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of maximal shed blood volume was returned in the form of Ringer lactate (RL). The animals were resuscitated with four times the volume of the shed blood with RL, during and after which ATP-MgCl2 (50 mumol/kg body wt) or an equal volume of normal saline was infused intravenously over 95 min. Cardiac output and organ blood flow were determined by 85Sr-labeled microspheres at 90 min after the completion of resuscitation. The results indicate that portal blood flow and total hepatic blood flow decreased significantly after hemorrhage and resuscitation. ATP-MgCl2 treatment, however, restored these parameters to sham values. In contrast, hepatic arterial blood flow did not change significantly after either hemorrhage and resuscitation or ATP-MgCl2 infusion. Moreover, the depressed cardiac output was normalized and coronary blood flow was higher than shams after ATP-MgCl2 treatment. Unlike small intestinal blood flow, blood flows to the stomach, spleen, pancreas, mesentery, and cecum were not markedly affected with ATP-MgCl2 infusion. Thus the restoration of hepatic blood flow with ATP-MgCl2 treatment under such conditions is due to the increased portal blood flow, i.e., solely due to the increased small intestinal blood flow.
Some Ways of Thinking

When thoughts overwhelm the mind, the mind puts them into the world. Talk, gesture, diagram, and sketch help not only to augment memory and information processing but also to structure thought and promote inferences and discovery. Research from many domains will be presented that highlights the similarities, differences, and special characteristics of each of these tools of thought.
Stepped-wedge randomised trial to evaluate population health intervention designed to increase appropriate anticoagulation in patients with atrial fibrillation

Background Clinical guidelines recommend anticoagulation for patients with atrial fibrillation (AF) at high risk of stroke; however, studies report 40% of this population is not anticoagulated. Objective To evaluate a population health intervention to increase anticoagulation use in high-risk patients with AF. Methods We used machine learning algorithms to identify patients with AF from electronic health records at high risk of stroke (CHA2DS2-VASc risk score ≥2), and no anticoagulant prescriptions within 12 months. A clinical pharmacist in the anticoagulation service reviewed charts for algorithm-identified patients to assess appropriateness of initiating an anticoagulant. The pharmacist then contacted primary care providers of potentially undertreated patients and offered assistance with anticoagulation management. We used a stepped-wedge design, evaluating the proportion of potentially undertreated patients with AF started on anticoagulant therapy within 28 days for clinics randomised to intervention versus usual care. Results Of 1727 algorithm-identified high-risk patients with AF in clinics at the time of randomisation to intervention, 432 (25%) lacked evidence of anticoagulant prescriptions in the prior year. After pharmacist review, only 17% (75 of 432) of algorithm-identified patients were considered potentially undertreated at the time their clinic was randomised to intervention. Over a third (155 of 432) were excluded because they had a single prior AF episode (transient or provoked by serious illness); 36 (8%) had documented refusal of anticoagulation, the remainder had other reasons for exclusion. The intervention did not increase new anticoagulant prescriptions (intervention: 4.1% vs usual care: 4.0%, p=0.86). Conclusions Algorithms to identify underuse of anticoagulation among patients with AF in healthcare databases may not capture clinical subtleties or patient preferences and may overestimate the extent of undertreatment. Changing clinician behaviour remains challenging.
Heat-driven acoustic phonons in lamellar nanoplatelet assemblies.

Colloidal CdSe nanoplatelets, with the electronic structure of quantum wells, self-assemble into lamellar stacks due to large co-facial van der Waals attractions. These lamellar stacks are shown to display coherent acoustic phonons that are detected from oscillatory changes in the absorption spectrum observed in infrared pump, electronic probe measurements. Rather than direct electronic excitation of the nanocrystals using a femtosecond laser, impulsive transfer of heat from the organic ligand shell, excited at C–H stretching vibrational resonances, to the inorganic core of individual nanoplatelets occurs on a time-scale of <100 ps. This heat transfer drives in-phase longitudinal acoustic phonons of the nanoplatelet lamellae, which are accompanied by subtle deformations along the nanoplatelet short axes. The frequencies of the oscillations vary from 0.7 to 2 GHz (3–8 μeV and 0.5–1 ns oscillation period) depending on the thickness of the nanoplatelets—but not their lateral areas—and the temperature of the sample. Temperature-dependence of the acoustic phonon frequency conveys a substantial stiffening of the organic ligand bonds between nanoplatelets with reduced temperature. These results demonstrate a potential for acoustic modulation of the excitonic structure of nanocrystal assemblies in self-assembled anisotropic semiconductor systems at temperatures at or above 300 K.
Intra-operative ketorolac 15 mg versus 30 mg for analgesia following cesarean delivery: a retrospective study.

Abstract Background Ketorolac is a nonsteroidal anti-inflammatory drug used as part of multimodal analgesia in women undergoing cesarean delivery. The lowest effective dose of ketorolac that best optimizes analgesia without increasing side effects is unclear. We performed this retrospective study to compare the analgesic efficacy of 15 mg or 30 mg ketorolac administered intra-operatively to our obstetric population. Methods We included patients who underwent cesarean delivery under neuraxial anesthesia and received 15 mg or 30 mg of ketorolac intra-operatively. Our multimodal analgesic regimen is standardized and includes 150 µg spinal or 3 mg epidural morphine, 975 mg rectal acetaminophen, and 15–30 mg intravenous ketorolac within 15 min of surgery completion. The primary outcome was opioid use in the first 6 h after surgery. Secondary outcomes were opioid use at 24 and 48 h, opioid dose, pain scores, breastfeeding, postoperative serum creatinine and need for rescue anti-emetics. Results One-thousand-three-hundred and forty-nine patients were analyzed (15 mg ketorolac n=999; 30 mg n=350). There was no difference between the two groups in patient demographics or intra-operative characteristics. There was no significant difference between groups for opioid use at 6 h after surgery (50.3% vs 52.0%, odds ratio [95% confidence interval] 1.13 [0.87 to 1.47]). There were also no significant differences between the groups for secondary outcomes. Conclusions There was no difference in opioid use between patients receiving either a 15 mg or a 30 mg dose of ketorolac given intra-operatively for postoperative analgesia following cesarean delivery.
Democratizing the dispute: democratization and the history of conflict management

What explains the complex processes of democratization and conflict management? Are new democracies more likely to use peaceful means or engage in militarized means when presented with opportunitie...
How Much to Open, How Fast to Fix and Develop? Impacts of Openness on Software Development and Maintenance

Proprietary software firms have recently begun to emulate the open source software community in opening up some of their software. We analyze this phenomenon in the context of resource allocation between fixing defects and the development of the next version of the software — an important issue that many software firms face in light of the prevalence of software defects. Based on the evidence from prior literature and current business practices, we develop our analytical models, more specifically optimal control models, to determine the conditions when a software firm should make its software fully open source or partially open source, or keep it proprietary. In our analysis, we consider various factors including: (i) the characteristics of the market (e.g., valuation of the software, market competitiveness, network effects, and market expectations from the next version of the software), (ii) the characteristics of the software firm (e.g., costs for developing software and fixing defects), and (iii) the effects of making the software fully or partially open source on the current and next versions of the software. Based on the results, we derive and discuss several important insights and shed light into the business practices of different software firms. Some of our findings include: (i) the software firm might keep its software proprietary even in conditions that seem to favor an open source software environment, (ii) if the software becomes more valuable, the software firm might decide to decrease the level of effort for fixing defects but rely more on the open source software community, and (iii) a decrease in the cost of collaboration with open source community might result in drastic changes in the behavior of the firm.
Chemical and Histologic Demonstration of Hydrochloric Acid-induced Release of Serotonin from Intestinal Mucosa

Summary Reduction of the serotonin content of the upper small intestine of the rat and degranulation of argentaflin cells were produced by perfusion with 0.1 N hydrochloric acid in physiologic amounts. A small fraction of intestinal 5-hydroxytryptamine was recovered intraluminally, which indicated a release phenomenon. It is suggested that acid-induced serotonin release may occur under physiologic circumstances.
The Coulomb Explosion and Recent Methods for Studying Molecular Decomposition

An account is given of the nature of a molecular Coulomb explosion, based on experimental studies of fragment ion spectra and their recoil energies resulting from photoionization of core shell electrons in gaseous molecules. The extent of multiple ionization in a vacancy cascade is discussed, and a simple model is used to predict the amount of kinetic energy possessed by the fragment ions. Data on both diatomic molecules containing light atoms and more complex molecules containing heavy atoms are reviewed.
A characterization of excitatory postsynaptic potentials in the avian nucleus magnocellularis

1. The activation of current-clamped neurons in the chick nucleus magnocellularis (nMAG) by eighth nerve stimulation has been studied in a brain slice preparation using patch electrodes. Single pre...
Redefining the Role of the Pharmacist: Medication Therapy Management

Purpose: The purpose of this paper is to explore better use of pharmacists in rural communities as a partial solution to scarcity of physicians and other health care providers. It discusses expected reduction in public subsidies for rural health care and the changing market for pharmacists. The paper emphasizes the use of pharmacists as a backdrop for description of Medication Therapy Management (MTM). A pilot study of MTM is also reported. Methods: This article explores rural health access, the market for pharmacists and MTM using the literature, and economic concepts to provide historical context for this new form of health care delivery. A small case study from a university-based clinic provided primary data to demonstrate viability. Findings: MTM can augment rural health by providing care for patients who receive increasing numbers of complex medications. It helps better integrate pharmacists into primary care and holds promise as a cost-effective, if not cost-saving alternative. Conclusion: More constrained fiscal conditions are a virtual certainty going forward. The rural health community needs cost-effective health care alternatives that can prosper with lower levels of public financial support. MTM is one such option.
Using Social Network Analysis To Examine the Time of Adoption of Computer-Related Services among University Faculty

AbstractResearch relating to the diffusion of innovations in education has been based primarily on looking at individual characteristics as predictors of use. This study proposes to use social network analysis and diffusion research to study the diffusion of two computer-based administrative services within a university faculty network. The relationship of time of adoption and the number of network nominations received, centrality closeness, spatial proximity, and organizational unit proximity were examined. Participants were 66 faculty members in a college of education at a southern university. They were introduced to the services and asked to provide demographic information and to identify communication partners for advice, friendship, and discussion. Results indicated that the number of friendship network nominations received was negatively correlated with the time of adoption. No correlation was found between time of adoption and spatial and organizational unit proximity.
The Effectiveness of State Technology Incentives: Evidence from the Machine Tool Industry, Executive Summary

Few economic issues have captured as much attention in recent years as the apparent decline in U.S. industrial competitiveness. Numerous studies prepared by various national commissions, policy organizations, and academics have documented industrial decline, uncovering its causes, and proposing remedies for U.S. industry. Most of the research has identified manufacturing as the industrial sector that has experienced the most serious erosion of cost and quality superiority. With a view toward building a stronger basis for such public policy decisions, researchers at the Center for Agricultural and Rural Development set out to study some essential questions about the efficiency of manufacturing. Using the machine tool industry from 1972 to 1987 as an example, the study, which is summarized here, examines determinants of manufacturing efficiency and plant survival, and the effectiveness of public policy. Manufacturing or industrial extension programs, which provide a variety of technical and managerial assistance, were chosen for policy evaluation. The study suggests public and private responses to the productivity crisis that might improve the competitiveness of manufacturing for industries experiencing problems similar to those observed in the machine tool industry.
Structure-based efforts to optimize a non-β-lactam inhibitor of AmpC β-lactamase.

Abstract β-Lactams are the most widely prescribed class of antibiotics, yet their efficacy is threatened by expression of β-lactamase enzymes, which hydrolyze the defining lactam ring of these antibiotics. To overcome resistance due to β-lactamases, inhibitors that do not resemble β-lactams are needed. A novel, non-β-lactam inhibitor for the class C β-lactamase AmpC (3-[(4-chloroanilino)sulfonyl]thiophene-2-carboxylic acid; K i 26 μM) was previously identified. Based on this lead, a series of compounds with the potential to interact with residues at the edge of the active site were synthesized and tested for inhibition of AmpC. The length of the carbon chain spacer was extended by 1, 2, 3, and 4 carbons between the integral thiophene ring and the benzene ring (compounds 4 , 5 , 6 , and 7 ). Compounds 4 and 6 showed minimal improvement over the lead compound ( K i 18 and 19 μM, respectively), and compound 5 inhibited to the same extent as the lead. The X-ray crystal structures of AmpC in complexes with compounds 4 , 5 , and 6 were determined. The complexes provide insight into the structural reasons for the observed inhibition, and inform future optimization efforts in this series.
A note on the calculation of the effective annual rate for cash discounts

Abstract This note describes an inconsistency, which has gone unnoticed for a number of years, between theoretical discussions of effective interest and the nature of cash discounts and the typical calculation of the effective annual rate for cash discounts presented in intermediate accounting textbooks. These calculations understate the effective rate because the amount presumed “borrowed” is the gross purchase price rather than the theoretically correct net purchase price. As educators, our arguments and problem solutions should be logically consistent and should convey a thorough understanding of the underlying theoretical constructs and their applications.
Fetal and neonatal rat pancreas in organ culture: age-related effects of corticosterone on the acinar cell component

Fetal rat pancreas (ages 16 to 22 days postcoitum) and neonatal pancreas (4 days postnatal) were grown in organ culture for four days. The medium consisted of chick embryo extract and rooster serum either with or without the addition of corticosterone (3 X 10(-5) M). Acinar cell differentiation was assessed using quantitative light microscopic linear scanning of tissue sections and enzymatic analysis of amylase in the culture media and in the explants. In the younger fetal tissue of 16 and 18 days postcoitum exocrine differentiation continued in vitro. The effect of corticosterone was an enhancement of the degree of in vitro differentiation. Even with corticosterone, however, the degree of differentiation in vitro was less than that observed during a similar period in vivo. In differentiated pancreas (20- and 22-day fetal neonatal) the acinar pancreas degenerated under control conditions and a selective growth of the endocrine pancreas was observed. The addition of corticosterone to the media resulted in a maintenance of the differentiated state of the acini except in 22-day fetal tissue in which the acini were not preserved. The differences between these results and the work of other investigators and the possible in vivo role of adrenocorticosteroids in exocrine pancreatic differentiation is discussed.
A QoS-oriented distributed routing protocol for hybrid networks

As wireless communication gains popularity, significant research has been devoted to supporting realtime transmission with stringent Quality of Service (QoS) requirements for wireless applications. At the same time, a wireless hybrid network that integrates a mobile wireless ad hoc network (MANET) and a wireless infrastructure network has been proven to be a better alternative for the next generation wireless networks. By directly adopting resource reservation-based QoS routing for MANETs, hybrids networks inherit invalid reservation and race condition problems in MANETs. How to guarantee the QoS in hybrid networks remains as an open problem. In this paper, we propose a QoS-oriented Distributed routing protocol (QOD) to enhance the QoS support capability of hybrid networks. Taking advantage of fewer transmission hops and anycast transmission features of the networks, QOD transforms the packet routing problem to a resource scheduling problem. QOD includes a QoS-guaranteed neighbor selection algorithm to meet the transmission delay requirement, a distributed packet scheduling algorithm to further reduce transmission delay, and mobility-based segment resizing algorithm that adaptively adjusts segment size according to node mobility in order to reduce transmission time. Analytical results show the QOD's properties of lower transmission delay and dynamism-resilience. Simulation results show that QOD can provide high QoS performance in terms of overhead, transmission delay, dynamism-resilience and scalability compared to a resource reservation-based mechanism.
Facial imaging in an urban emergency department

To describe the facial imaging practice pattern in our an emergency department and to assess the implications of this practice, a retrospective review was conducted of patients with blunt facial trauma requiring facial imaging over a 2-month period. Patients were compared based on their initial imaging study, either facial x-rays (primary FXR) or spiral computed tomography (primary FSCT). Of 211 patients imaged, 148 (70%) received primary FXR and 63 (30%) primary FSCT. A greater proportion of primary FSCT patients had at least one fracture detected (57% v. 26%; odds ratio 3.9, confidence interval 2.0-7.5). Of patients with a fracture on FXR, 29% underwent secondary FSCT. The average facial imaging charges per case detected (patient with a fracture) were $978 for primary FXR and $2,048 for primary FSCT. Physicians made avid use of FSCT. Additional studies are needed to determine the appropriateness of this practice and to improve clinical selection of patients requiring FSCT.
The Great American Medicine Show Revisited

Since the late 1800s, changes in the advertising and marketing of medicinal drugs have produced heated debates in the United States. With the emergence of the modern prescription drug between 1938 and 1951, concerns that once focused primarily on patients' use of over-the-counter drugs were broadened to include physicians and their "doctors' drugs" as well. The medical profession's growing control over their patients' drug choices inevitably heightened the scrutiny of their own performance as consumers. Although deeply divided over issues of the patient's role in medical decision making, consumer activists and physician reformers expressed similar concerns about the impact of aggressive pharmaceutical marketing and advertising on the doctor-patient relationship, and starting in the late 1950s they employed strikingly similar strategies to counter the new corporate "medicine show." Yet their efforts to promote a more rational use of prescription drugs have usually been too little and too late to offset the effectiveness of pharmaceutical advertising and mar-keting activities.
Liquid Crystals in an Electric Field

IT has long been known that nematic liquid crystals show remarkable orientation effects in electric fields as well as in magnetic fields1. We have observed the formation of domains in thin layers of the liquid crystal phase of several organic compounds. Typical results were obtained with p-azoxyanisole, The domains form in electric fields of about 3,000 V/cm. Their appearance and behaviour suggest several properties of liquid crystals which have not previously been reported.
On a relation between detection and estimation in decision theory

It is shown that in the estimation of an arbitrary signal corrupted by additive Gaussian noise, the optimum minimum-variance estimator is always a simple linear transformation of the logarithmic gradient of the average likelihood ratio which is obtained in the optimum detection of the same signal. Conversely, the average likelihood ratio can always be expressed in a simple functional form containing only the minimum-variance estimator of the unknown signal.
Miocene invertebrate trace fossils from a braided river environment, western Nebraska, U.S.A

Abstract Lower Miocene cross-stratified sands of the Gering and Monroe Creek Formations exposed on Scotts Bluff National Monument in western Nebraska, U.S.A., were deposited by migrating sand bars in a braided river system similar to the modern Platte River in eastern Nebraska and, like the Platte, contain local lenses of parallel stratified sediment that accumulated in ponded areas of abandoned channels. During times of low discharge, broad areas of river bar sands and abandoned channel sediments were subaerially exposed on the Miocene river plain. These sediments, like those exposed in the Platte River today, were subjected to burrowing by insects and other animals. Trace fossils in Lower Miocene braided river deposits are: vertical shelter burrows, horizontal deposit-feeding burrows, bioturbated layers, and vertical passageways between bioturbated layers. The burrows are cylindrical to sub-cylindrical in cross-section, internally meniscate or massive, generally non-branching, and smooth walled. Shelter burrows are similar in shape and size to recent burrows dug by beetles in river sediment for protection from day-time temperatures, to pass the night, and to hibernate. The shelter burrows, deposit-feeding burrows, and vertical passageways in the Lower Miocene sediments occur in four distinct “populations” with modal diameters of 1–2, 3–4, 7–8, and 10–12 mm. The occurrence of both vertical and horizontal burrows in all four “populations” suggests that they could have been made by the same insect. “Populations” with modal diameters of 1–2, 3–4, and 7–8 mm also occur in modern Platte River sediment and are made by tiger-beetle larvae (3–4 mm) and heterocerid (1–2 mm) beetles. Miocene shelter burrows, deposit-feeding burrows, bioturbated layers, and vertical passageways, therefore, could have been formed by different types of beetles, and/or larval instars and adults of the same beetle species.
Purification and properties of 2-hydroxy-6-oxo-6-(2′-aminophenyl)hexa-2,4-dienoic acid hydrolase involved in microbial degradation of carbazole

Hydrolysis following meta-ring cleavage by a dioxygenase is a well-known step in aromatic compound metabolism. The 2-hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid hydrolase from Pseudomonas LD2 is a new member of the small group of characterized aromatic hydrolases that catalyze the cleavage of C-C bonds. In this study, the His(6)-tagged 2-hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid (HOPDA) hydrolase was purified from a recombinant Escherichia coli strain utilizing immobilized metal affinity chromatography. 2-Hydroxy-6-oxo-6-(2'-aminophenyl)hexa-2,4-dienoic acid hydrolase is a colorless homodimer with no cofactor requirement. The enzyme actively converted HOPDA into benzoic acid and 2-hydroxypenta-2,4-dienoic acid. The enzyme exhibited activity between pH 6.5 and 10.5 with a maximum activity at pH 7.0. The optimum temperature at pH 7.0 was 60 degrees C. The calculated K'(m) for HOPDA was 4.6 microM, the V(max) was 3.3 micromol min(-1), and the K(s) was 70.0 microM. This corresponds to a maximum specific turnover rate of 1300 HOPDAs(-1)dimer(-1). The deduced amino acid sequence of CarC showed 30.3, 31.3, and 31.8% identity with TodF (P. putida F1), XylF (P. putida), and DmpD (Pseudomonas sp. CF600), respectively, which are meta-cleavage compound hydrolases from other Pseudomonads. The amino acid sequence Gly-X-Ser-X-Gly, which is highly conserved in these hydrolases, is also found in CarC. Lysates from a strain expressing enzyme in which the putative active site serine is mutated to alanine showed a significant reduction in activity.
Synthetic carotenoid derivatives prevent photosensitised killing of retinal pigment epithelial cells more effectively than lutein.

Abstract We studied the photosensitised killing of retinal pigment epithelial (RPE) cells using two photosensitisers that localise in lysosomes. The ARPE-19 cell line was photosensitised using either acridine orange or cis-di(4-sulfonatophenyl)diphenylporphine. We then measured the amount of photoprotection provided to RPE cells by five synthetic carotenoid derivatives and by lutein. The synthetic carotenoid derivatives studied were the Girard's reagent P derivative (GRP) of retinal (GRP-retinal), the GRP derivative of β-apo-8′-carotenal (GRP-carotenal), the Girard's reagent T derivative of β-apo-8′-carotenal (GRT-carotenal), the GRP derivative of canthaxanthin ((GRP)2-canthaxanthin) and the dansyl hydrazine derivative of β-apo-8′-carotenal (dansyl-carotenal). We found that GRP-carotenal, GRT-carotenal (GRP)2-canthaxanthin and dansyl-carotenal were effective photoprotectors. All of these carotenoids had large singlet-oxygen quenching constants and had chemical structures designed to localise either in mitochondria or in lysosomes. In contrast, lutein and GRP-retinal were not effective photoprotectors. The failure of GRP-retinal to provide significant photoprotection may have been due to its relatively low singlet-oxygen quenching constant. Lutein is a potent singlet-oxygen quencher, but may not have provided significant photoprotection in this model because the lutein may have had a different subcellular distribution than the photosensitisers used.
Effectiveness of dietary essential fatty acid deficiency in development of a model of endogenous renal prostaglandin deficiency.

Abstract An essential fatty acid deficient diet (EFAD) was administered to rats to determine the feasibility of using a model of endogenous arachidonic acid deficiency to study the role of prostaglandins in the kidney. Beginning at weaning rats were fed a diet containing less than 0.2% linoleic acid. Prostaglandin E (PGE) production was determined in vitro by stimulation of renal papillary slices with 1500 m0sm NaCl in Krebs-Henseleit buffer and in vivo by 24 hour urine collection. EFAD caused a reduction of arachidonic acid in the renal papilla to 13% of levels in control rats (P In vitro PGE release from incubated papillae of EFAD rats was barely detectable at baseline but increased with stimulation to approximately 50% of PGE levels observed in normal tissues. Urinary PGE, volume and sodium excretion were not significantly different between EFAD and control rats. These results suggest that despite significant differences in arachidonic acid stores between EFAD and normal rats, the usefulness of this animal model to study prostaglandin-mediated events may be limited by the residual capacity of the EFAD papilla to produce prostaglandin.
Gender, Attributional Styles, and Direction of Lethal Violence A Partial Test of an Integrated Model of Suicide and Homicide

The present study is a partial test of Unnithan, Huff-Corzine, Corzine, and Whitt's integrated model of suicide and homicide, focusing specifically on gender differences in the suicide-to-homicide ratio (SHR). In light of prior research on the differential attributional styles of men and women, the underlying assumption of Unnithan et al. regarding attribution of blame and direction of lethal violence is assessed. Using aggregate national suicide and homicide rates for the years 1979 through 1997, SHRs and lethal violence rates (LVRs) are calculated and compared by gender. Analyses reveal that women's SHRs are substantially higher than those for men. In addition, it is found that trends in LVRs over time are significantly different for men and women, exhibiting a cyclical pattern in the case of men and a linear pattern in the case of women. Implications of these findings for the integrated model and for future research are discussed.
Devaluation versus Import Restriction as an Instrument for Improving Foreign Trade Balance

FOR ANY COUNTRY or trading area except a very small one, a devaluation can generally be expected to bring a decline in the foreign price of its exports. If, instead of devaluing, a country should achieve the same improvement in its foreign trade balance by a restriction of imports, whether through a tariff or by quantitative restrictions, the foreign price of its exports would not fall significantly.' Consequently, the value of exports and imports that must be sacrificed in order to achieve a given improvement in the foreign balance through devaluation exceeds, for such a country or trading area, the value of the imports that must be sacrificed in order to achieve an equal improvement of the foreign balance through import restriction or a tariff. If, then, the welfare value of a dollar's worth 2 of imports is equal to the welfare value of a dollar's worth of exports, it costs the country less to use import restriction rather than devaluation as an instrument for improving the foreign balance, subject to the qualifications mentioned below.
On identifying codes in the Cartesian product of a path and a complete graph

Identifying codes in the Cartesian product of a complete graph and a path are considered. After proving a set of sufficient conditions for a set in such a graph to be an identifying code, we then construct minimum identifying codes when the complete graph is of order three or at least five, and when the path is of order at least three.
Material instability with stress localization

This paper is concerned with a possible form of material instability arising from a non-unique dependence of stress on deformation and leading to heterogeneous states of stress in otherwise homogeneous deformations. Following a discussion of certain theories and experiments that suggest this type of stress behavior, an analysis is given of some possible quasi-static bifurcations of steady-state stress fields for extensional motions of isotropic elastic solids and viscoelastic fluids. These involve extended lamellar and axisymmetric phase structures having common extension. For certain other restricted forms of non-linear elasticity, the classical Eshelby [Proc. R. Soc. London A 241 (1957) 376] theory is employed to describe dilute ellipsoidal phases having a deformation different from the globally imposed mean.
Electrophysiologic interactions of antipsychotic drugs with central noradrenergic pathways.

The pathway from the nucleus coeruleus to Purkinje neurons in rat cerebellar cortex was used to analyze effects of antipsychotic neuroleptic drugs on a central noradrenergic pathway. Fluphenazine and haloperidol produced a dose-dependent increase in Purkinje neuron spontaneous discharge. This effect was not seen in animals in which the noradrenergic input had been removed by the neurotoxin 6-hydroxydopamine. In contrast, the effects of neuroleptics were still present in animals which had received neonatal X-ray irradiation, which destroys intrinsic inhibitory and excitatory pathways in cerebellar cortex. Chlorpromazine produced the same increase in discharge rate, but was significantly less potent. α-Flupenthixol was equipotent with fluphenazine, but β-flupenthixol, a behaviorally inactive steroisomer, was without effect. The dose-response curves showed potencies similar to those in several animal behavioral paradigms. In addition, the rank order of potency was identical to that in clinical tests of antipsychotic activity. Three-week chronic administration of fluphenazine resulted in complete blockade of noradrenergic activity, with no further increase in Purkinje neurons spontaneous discharge rate by additional doses of drug. Thus, tolerance does not develop to the noradrenergic blocking effect of the neuroleptic. Taken together, this evidence suggests that antipsychotic neuroleptic drugs block noradrenergic neurotransmission in the CNS.
The development of a sensitive and specific radioreceptor assay for leukotriene B4.

To establish a simple and sensitive quantitation of leukotriene B/sub 4/ (LTB/sub 4/), they developed a radioreceptor assay (RRA) using a highly specific (/sup 3/H)leukotriene B/sub 4/((/sup 3/H)LTB/sub 4/) binding to a guinea pig spleen homogenate. The assay detected LTB/sub 4/ levels as low as 0.12 pmol per tube. 50% inhibition of bound (/sup 3/H)LTB/sub 4/ was obtained by 2.5 nM of unlabeled LTB/sub 4/. (/sup 3/H)LTB/sub 4/ competition studies indicated that 20-hydroxy-LTB/sub 4/ was 8 times, 6 trans-LTB/sub 4/ was 640 times and 20-carboxy-LTB/sub 4/ was 1000 times less effective than LTB/sub 4/. The peptide leukotrienes C/sub 4/, D/sub 4/ and E/sub 4/ showed no effect on (/sup 3/H)LTB/sub 4/ binding. Recovery rates averaged 97% after ethanol extraction and evaporation of known amounts of LTB/sub 4/. The intra-assay coefficients of variation for three samples were 2.4%, 7.2% and 8.4%, respectively. This assay was validated by measuring LTB/sub 4/ released from human granulocytes stimulated with calcium ionophore A23187. The LTB/sub 4/ level was maximal at 10 min and decreased rapidly after 15 min. This radioreceptor assay for leukotriene B/sub 4/ is highly sensitive and is comparable to the reported sensitivity by radioimmunoassay. The method is simpler and less expensive thanmore » other methods such as high pressure liquid chromatography and is suitable for routine measurement of leukotriene B/sub 4/.« less