cssi/SciSciGPT-SciSciNet huggingface dataset:
Lithium diisopinocampheylamide: a new and highly effective chiral catalyst in the enantioselective deprotonation of meso-epoxides

Abstract α-Pinene based novel chiral lithium amides have been used for the catalytic enantioselective deprotonation of cyclohexene oxide. An enantiomeric excess of up to 95% for ( R )-2-scyclohexen-1-ol was achieved with lithium (−)- N , N -diisopinocampheylamide. A systematic study shows that the isopinocampheyl moiety plays an important role in achieving high enantioselectivity.
Pregnancy, labour and delivery in a Jehovah’s Witness with esophageal varices and thrombocytopenia

Purpose: An increasing number of women with cirrhosis are conceiving and carrying their pregnancies to term. However, the maternal mortality rate remains high (10 – 61%). This case report describes the management of a parturient with esophageal varices and thrombocytopenia. She was also a Jehovah’s Witness.
Nanocomposite materials with antimicrobial activity based on chitosan

Chitosan nanoparticles (CNP) were prepared by ionic gelation using sodium tripolyphosphate. Metal-enhanced CNP were prepared using the same procedure in the presence of Cu 2+ and Ag+, respectively. The nanoparticulate materials were characterised by FTIR, SEM and antimicrobial assays. The CNP showed higher antimicrobial effect than chitosan against S. saprophyticus and E. coli . The effect did not seem to depend on the molecular weight of the starting chitosan. Cu 2+ and Ag+, both known as antimicrobial agents, showed synergistic effects with chitosan against both organisms. The skin regenerative potential of CNP and metal-enhanced CNP was tested by assessing skin cell (fibroblast, keratinocyte) proliferation. The present study also suggests that chitosan and its nanoparticles inhibits MMP-1 expression in skin fibroblasts and keratinocytes, and may thereby inhibit skin aging and facilitate the ECM remodelling phase of wound healing.
Ethical ramifications of alternative means of recruiting research participants from cancer registries.

BACKGROUND The protection of confidentiality and the extent to which voluntary and meaningful informed consent can be obtained from potential participants are critical when recruiting patients for clinical research from cancer registries. In the current study the authors describe the influence of two methods of recruitment from a cancer registry (direct contact by research staff and contact by research staff after physicians alert potential participants) on these issues. METHODS Enrollment rates were tabulated using each recruitment method and complaints received from potential participants regarding recruitment were reviewed. RESULTS Of 416 women approached to participate, the first 351 women were recruited by way of direct contact by research staff and the remaining 65 women were recruited by research staff after their physician had sent them an alert letter. There was no difference in the enrollment rate using the two methods. One potential participant believed that her confidentiality had been violated and another hung up the telephone when contacted directly; two potential subjects reported feeling pressure to participate because their physician sent them a letter. CONCLUSIONS Although concerns regarding violating confidentiality clearly are justified when recruiting research participants from cancer registries, patients also may feel pressure to participate if physician notification is part of the process. It is incumbent on investigators and institutional review boards charged with overseeing this research that they respect confidentiality and avoid pressuring persons to participate in research. It also is critical that persons whose medical information will be entered into cancer registries be informed about this process as well as how the registry will be used for research. Cancer 1999;86:647–51. © 1999 American Cancer Society.
Thoracic Outlet Syndrome Caused by Fibrous Dysplasia of the First Rib

Fibrous dysplasia causing thoracic outlet syndrome is rare. A 41-year-old woman presented with neurogenic thoracic outlet syndrome with imaging that demonstrated a large tumor of her proximal left first rib. Transaxillary excision was unsuccessful due to involvement of the subclavian vasculature and brachial plexus. Subsequent posterolateral thoracotomy and resection of her first rib revealed fibrous dysplasia. Thoracotomy should be considered in these cases for optimal vascular control and identification of thoracic outlet anatomy.
Broadband Epsilon-Near-Zero Metamaterials with Step-like Metal-Dielectric Multilayer Structures with Gain Media

The broadband epsilon-near-zero metamaterials consisting of step-like metal-dielectric multilayer structures with gain media is proposed. Low-loss functional optical devices including prisms for broadband directional emission and S-shaped lenses for phase front shaping are demonstrated.
Applicability of the critical strain fracture criterion to WC-Co hard metals

Abstract A generally accepted view that the fracture of hard metals needs to be modeled as a ductile event (their macroscopic brittle behavior notwithstanding) to account for the microplasticity of the binder phase, led to various attempts in the past to apply the Rice-Johnson model for ductile failure to the fracture of hard metals. The present work is an attempt to take these analyses a step further and is based on the concept of a crack tip process zone in which the contiguous carbide, since it is most severely stressed, is broken owing to microcracking and therefore does not contribute to the load-carrying capacity of the process zone. This leads to an expression relating fracture toughness and microstructural parameters of hard metals. The relationship contains one floating parameter for which reasonable values are obtained when the predictions of the present model are fitted to the available experimental data for WC-Co alloys with binder volume fractions approximately in the range 0.10–0.25.
Optimization of patient dose and image quality with z-axis dose modulation for computed tomography (CT) head in acute head trauma and stroke

The purpose of this study is to retrospectively analyze the effect of z-axis modulation for CT head protocols on patient dose and image quality in patients with acute head trauma and stroke. The study was approved by the Institutional Review Board. We retrospectively evaluated the effect of dose modulation on unenhanced CT head examinations in patients with acute head trauma and stroke. Two series of 100 consecutive studies were reviewed: 100 studies performed without dose modulation, 100 studies performed with z-axis dose modulation. Multidetector 16-section CT was performed sequentially and axial 5-mm-thick slices were obtained from base of skull to vertex. With z-axis dose modulation, the same tube current range was maintained, but a computer algorithm altered the tube current applied to each CT section. For each examination, the weighted volume CT dose index (CTDI (vol)) and dose-length product (DLP) were recorded and noise was measured. Each study was also reviewed for image quality by two independent, blinded readers. The variables (CTDI (vol) and DLP, image quality, and noise) in the two groups were compared by using student t test and Wilcoxon rank-sum test. For unenhanced CT head examinations, the CTDI (vol) and DLP, respectively, were reduced by 35.8% and 35.2%, respectively, by using z-axis dose modulation. Image quality and noise were unaffected by the use of this dose modulation technique (P < 0.004). Utilization of z-axis modulation technique for CT head examination in patients with acute head trauma and stroke offers significant radiation dose reduction while image quality is optimally maintained.
Distributed Optimal Beamformers for Cognitive Radios Robust to Channel Uncertainties

Through spatial multiplexing and diversity, multi-input multi-output (MIMO) cognitive radio (CR) networks can markedly increase transmission rates and reliability, while controlling the interference inflicted to peer nodes and primary users (PUs) via beamforming. The present paper optimizes the design of transmit- and receive-beamformers for ad hoc CR networks when CR-to-CR channels are known, but CR-to-PU channels cannot be estimated accurately. Capitalizing on a norm-bounded channel uncertainty model, the optimal beamforming design is formulated to minimize the overall mean-square error (MSE) from all data streams, while enforcing protection of the PU system when the CR-to-PU channels are uncertain. Even though the resultant optimization problem is non-convex, algorithms with provable convergence to stationary points are developed by resorting to block coordinate ascent iterations, along with suitable convex approximation techniques. Enticingly, the novel schemes also lend themselves naturally to distributed implementations. Numerical tests are reported to corroborate the analytical findings.
A comparison of endovascular repair versus open repair of abdominal aortic aneurysms in a community setting.

ObjectiveTo compare outcomes between endovascular versus surgical repair of abdominal aortic aneurysms (AAA) in a community hospital setting.MethodsA retrospective analysis of all patients undergoi...
An AC magnetohydrodynamic micropump

Abstract A microfluidic pump is presented using an AC magnetohydrodynamic (MHD) propulsion system in which the Lorentz force is used to propel an electrolytic solution along a microchannel etched in silicon. This micropump has no moving parts, produces a continuous (not pulsatile) flow and is compatible with solutions containing biological specimens. Theory, fabrication method and experimental results are described.
Vβ gene polymorphism and a major polyclonal T cell receptor idiotype

Summary Genetic polymorphism in the β variable gene pool (V β ) is responsible for the strain-specific distribution of the KJ16 T cell receptor (TcR) marker on 20% of peripheral T cells. KJ16 * strains carry two homologous V β genes that are absent in KJ16 − strains. All functional KJ16 * T cell hybrids tested express a member of this V β subset. mRNA hybridizing to this variable-region probe can be easily detected in total splenic T cells of a prototype KJ16 * strain. Thus, 20% of the TcR from the cytotoxic and helper T cell population, with various MHC restrictions and antigen reactivities, can be generated from two V β genes. However, their deletion appears to have no effect on the functionality of the T cell repertoire.
Golf-Inhibiting Gynecomastia Associated with Atorvastatin Therapy

Gynecomastia can have a significant emotional and social impact on men. Although numerous drug therapies may cause this condition, we found no documented cases of gynecomastia associated with atorvastatin. We describe the development of breast enlargement and tenderness in a 52-year-old Caucasian man 6 months after his simvastatin therapy had been switched to atorvastatin. His symptoms ultimately interfered with his ability to play golf and participate in other activities. These problems resolved after atorvastatin discontinuation and did not recur despite resumption of simvastatin therapy. The gynecomastia in this patient represented a possible adverse effect of atorvastatin according to the Naranjo adverse drug reaction probability scale. The mechanism may be atorvastatin's theoretical suppression of adrenal or gonadal steroid production through effects on cholesterol synthesis. Based on this and other case reports, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) should be considered as a potential cause when evaluating otherwise unexplainable cases of gynecomastia in patients taking these drugs.
Fertility issues for men with newly diagnosed prostate cancer.

Objectives With the increased use of prostate-specific antigen screening, younger men are being diagnosed with prostate cancer. A subset of these men is still interested in potentially having children after cancer treatment. To our knowledge, the topic of future fertility in patients with newly diagnosed prostate cancer has not previously been reported. Methods The charts of 8 patients with prostate cancer who were interested in future fertility before treatment were retrospectively reviewed. Preceding definitive treatment, the men underwent fertility counseling and were counseled to preserve semen before treatment. Results All 8 patients decided to have their semen stored using cryopreservation before their operation. After undergoing radical prostatectomy, one of the patients and his wife underwent successful intrauterine insemination and bore a child. Conclusions A subset of men, regardless of age, diagnosed with prostate cancer will be interested in preserving their fertility for the future. Fertility options and potential counseling should be part of the routine pretreatment appointments in men undergoing treatment of prostate cancer.
Web robot detection techniques: overview and limitations

Most modern Web robots that crawl the Internet to support value-added services and technologies possess sophisticated data collection and analysis capabilities. Some of these robots, however, may be ill-behaved or malicious, and hence, may impose a significant strain on a Web server. It is thus necessary to detect Web robots in order to block undesirable ones from accessing the server. Such detection is also essential to ensure that the robot traffic is considered appropriately in the performance and capacity planning of Web servers. Despite a variety of Web robot detection techniques, there is no consensus regarding a single technique, or even a specific "type" of technique, that performs well in practice. Therefore, to aid in the development of a practically applicable robot detection technique, this survey presents a critical analysis and comparison of the prevalent detection approaches. We propose a framework to classify the existing detection techniques into four categories based on their underlying detection philosophy. We compare the different classes to gain insights into those characteristics that make up an effective robot detection scheme. Finally, we discuss why the contemporary techniques fail to offer a general solution to the robot detection problem and propose a set of key ingredients necessary for strong Web robot detection.
Information assurance in sensor networks

Sensor networks are deployed to monitor the surroundings and keep the end-user informed about the events witnessed. Different types of events have different levels of importance for the user. Information Assurance is an ability to disseminate different information at different assurance levels to the end-user. The assurance level is determined by the criticality of the sensed phenomenon. Thus, information assurance capability allows a sensor network to deliver critical information with high assurance albeit potentially at a higher cost, while saving energy by delivering less important information at a lower assurance level.In this paper, we look at the problem of efficient information assurance in sensor networks when the assurance level of information is defined as the probability of information delivery (desired reliability) to the sink. We propose a new scheme for information delivery at a desired reliability using hop-by-hop broadcast. We show how the wireless broadcast can be utilized to increase the packet delivery rate at each hop and attain a desired reliability at minimal cost. Finally, we derive the optimal strategy for allocation of desired reliabilities at each hop in order to attain any given desired end-to-end reliability.
The role of enucleation with or without septal myectomy for discrete subaortic stenosis

Objective Substantial controversy persists regarding the need and efficacy of a routine myectomy in the treatment of discrete subaortic stenosis. Although some believe myectomy more effectively relieves subaortic narrowing, this is uncertain, and complications, including heart block and aortic valve injury, are concerns. The aims of the study were as follows: (1) to analyze the role of enucleation for relief of subaortic stenosis and the risk factors associated with recurrence and reoperation and (2) to delineate the characteristics of the patients who might benefit from enucleation alone. Methods From January 1990 through May 2007, 221 patients with subaortic stenosis underwent biventricular repair. Of those, 106 patients had discrete subaortic stenosis. The preoperative peak left ventricular outflow tract gradient, as determined by means of transthoracic echocardiographic analysis, was 67.3 ± 29 mm Hg. Forty patients had previous operations for other intracardiac anomalies. Mean age at repair was 7 years. Sixty-one patients underwent isolated enucleation, and 45 patients underwent concomitant myectomy. Patients with recurrent subaortic stenosis whose first operation was performed elsewhere were excluded from analysis. Results There was 1 early death and 1 late death. The postoperative peak left ventricular outflow gradient decreased to 12.5 ± 12.9 mm Hg (P Conclusions For those patients undergoing primary operations for discrete subaortic stenosis, routine myectomy does not offer superior relief of left ventricular outflow tract obstruction; enucleation alone provides good results in this selected population. However, in those patients with associated cardiac anomalies, concomitant additional myectomy is recommended.
Mars Exploration Rover telecommunications subsystem

The Mars Exploration Rover (MER) mission is designed to investigate Martian geology, investigate the role of water, and seek information on the climate history of the red planet at two sites. The Telecommunications Subsystem consists of the Radio Frequency Subsystem (RFS) operating at 7.1/8.4GHz (X-band), the Ultra High Frequency (UHF) Subsystem operating at 401/437MHz, the RFS and UHF Antenna Subsystem and the Radar Altimeter Subsystem (RAS) operating at 4.3 GHz (C-band). Science data return is enhanced through UHF relay communications with the Mars Odyssey (ODY) orbiter up to 128 kbps. Relay communications will also be demonstrated with the ESA Mars Express orbiter.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Formation of mutagenic activity from amino acids heated at cooking temperatures.

Abstract To investigate the formation of aromatic amine-like mutagenic activity in cooked grain foods, amino acids were heated alone or in binary combinations at either 150 or 210°C. About half of the binary mixtures of arginine heated with other amino acids produced potent mutagenic responses in the Ames/Salmonella assay, but only cysteine produced mutagenic products when heated alone. One-to-one molar ratios of arginine heated with threonine, valine, cystine, cysteine or tryptophan produced reaction products that gave 1200–3200 revertants/mmol in Salmonella strain TA98 with metabolic activation. 1-Methylguanidine, a fragment of arginine, produced a mutagenic response when heated alone or in binary mixtures with all amino acids tested. Analysis of reaction product extracts by solid-phase extraction and HPLC failed to find the known heterocyclic amines commonly found in cooked meats that would explain the measured mutagenic activity. As judged by biological and chemical characterization, several new aromatic amine mutagens are formed by heating some simple amino acids combined with arginine, and these reactants may be the source of the mutagenic products detected in the extracts of some cooked grain-based foods.
The etiology of spontaneous gastric perforation of the newborn: A reevaluation

Twenty-eight infants with spontaneous neonatal gastric perforation are analyzed along with 10 newborn stomachs experimentally disrupted pneumatically at autopsy. Nineteen infants survived surgical closure of the perforation. Prematurity and delay in diagnosis were significant findings in the nonsurvivors. The location of the perforations and their gross and microscopic appearance led to the assumption that these perforations were mechanical disruptions. Comparison of the clinical material with the experimental material, and proven mechanical disruptions in the literature, along with theoretic considerations, are in support of this hypothesis.
The effect of pictured visual cues on elicited sentence imitation.

Abstract In one experiment language-normal 6 1 2 -year-old and 4 1 2 -year-old children ( N = 68) were asked to imitate sentences with or without pictured visual cues. In a second experiment groups of language-disordered children ( N = 43) also 4 1 2 and 6 1 2 years of age were asked to imitate sentences with and without pictured visual cues. In both experiments there was no significant difference in the syntactical and grammatical quality of elicited imitations between conditions. Older children performed better than younger children in both experiments. It was concluded that pictured visual cues do not affect the syntactical and grammatical quality of language-normal and language-disordered children's elicited sentence imitations.
MEET DB2: automated database migration evaluation

Commercial databases compete for market share, which is composed of not only net-new sales to those purchasing a database for the first time, but also competitive "win-backs" and migrations. Database migration, or the act of moving both application code and its underlying database platform from one database to another, presents a serious administrative and application development challenge fraught with large manual costs. Migration is typically a high cost effort due to incompatibilities between database platforms. Incompatibilities are caused most often by product specific extensions to language support, procedural logic, DDL, and administrative interfaces. The migration evaluation is the first step in any competitive database migration process. Historically this has been a manual process, with the high costs and subjective results. This has led us to reexamine traditional practices and explore an automatic, innovative solution.We have designed and implemented the Migration Evaluation and Enablement Tool for DB2 for Linux Unix and Windows, or MEET DB2, a tool for automatically evaluating database migration projects. Encapsulated in a simple one-click interface, MEET DB2 is able to provide detailed evaluation of migration complexity based on its deep analysis on the source database. In this paper, we present MEET DB2, and discuss many aspects of our design, and report measurements from real-world use cases. In particular, we show a novel way to use XML and XQuery in this domain for better extensibility and interoperability. We have evaluated MEET DB2 on 18 source code samples, covering nearly 1 million lines of code. The utility has provided benefits in several dimensions including: dramatically reduced time for evaluation, consistency, improved accuracy over human analysis, improved reporting, reduced skill requirements for migration analysis, and clear analytics for product planning.
Calcium binding protein immunoreactivity in a reptilian thalamic reticular nucleus

Immunoreactivity to antisera directed against a variety of calcium binding proteins was investigated in the thalamic reticular nucleus of one species of reptiles, Caiman crocodilus. Cells and fibers were immunoreactive for parvalbumin whereas fibers but not neurons were immunoreactive for calbindin and calcitonin gene related peptide. These data support the observations that Caiman thalamic reticular nucleus contains at least two neuronal populations. One group, whose cells are immunoreactive for parvalbumin, forms at least part of the projection to the dorsal thalamus. The other group, which contains qualitatively different and sparser number of neurons, is immunoreactive for glutamic acid decarboxylase.
The Relationship of Authoritarianism and Related Constructs to Attitudes Toward Homosexuality1

Two studies examined the relationships of right-wing authoritarianism (RWA), dogmatism, social dominance orientation (SDO), and political-economic conservatism (PEC) to attitudes toward homosexuality. Study I, a meta-analysis, found that all 4 variables were related to attitudes toward homosexuality, with RWA having the largest relationship. Study 2 examined the relationships of the 4 variables to attitudes toward lesbians and gay men in a college-student sample. Although all 4 variables had zero-order correlations with these attitudes, RWA and SDO were the primary predictors, with RWA having the larger relationship. In addition, the zero-order correlations of PEC and dogmatism could be explained by their overlap with SDO and RWA, and SDO partially mediated the gender difference found in attitudes toward gay men.
Diffusion Archaeology for Diffusion Progression History Reconstruction

Diffusion through graphs can be used to model many real-world process, such as the spread of diseases, social network memes, computer viruses, or water contaminants. Often, a real-world diffusion cannot be directly observed while it is occurring -- perhaps it is not noticed until some time has passed, continuous monitoring is too costly, or privacy concerns limit data access. This leads to the need to reconstruct how the present state of the diffusion came to be from partial diffusion data. Here, we tackle the problem of reconstructing a diffusion history from one or more snapshots of the diffusion state. This ability can be invaluable to learn when certain computer nodes are infected or which people are the initial disease spreaders to control future diffusions. We formulate this problem over discrete-time SEIRS-type diffusion models in terms of maximum likelihood. We design methods that are based on sub modularity and a novel prize-collecting dominating-set vertex cover (PCDSVC) relaxation that can identify likely diffusion steps with some provable performance guarantees. Our methods are the first to be able to reconstruct complete diffusion histories accurately in real and simulated situations. As a special case, they can also identify the initial spreaders better than existing methods for that problem. Our results for both meme and contaminant diffusion show that the partial diffusion data problem can be overcome with proper modeling and methods, and that hidden temporal characteristics of diffusion can be predicted from limited data.
Cellular determination in the xenopus retina is independent of lineage and birth date

Xenopus embryos injected with tritiated thymidine throughout the stages of embryonic retinal neurogenesis showed that more than 95% of the embryonic retinal cells are born within a 25 hr period. While there are shallow central to peripheral, dorsal to ventral, and interlaminar gradients of neurogenesis in these eyes, throughout most of this 25 hr period, postmitotic cells are being added to all sectors and layers. Small clones of differentiated retinal neurons and glia derived from single neuroepithelial cells injected with HRP. These clones were elongated radially. They were also composed of many different combinations of cell types, suggesting a mechanism whereby determination is arbitrarily and independently assigned to postmitotic cells. Such a model, when tested statistically, fits our data very well. We present a scheme for cellular determination in the Xenopus retina in which a coherent group of clonally related cells stretch out radially as lamination begins. This brings different cells into different microenvironments. Local interactions in these microenvironments then lead the cells toward specific fates.
Adenyl cyclase in the toad bladder

Abstract Preparation of hormone sensitive adenyl cyclase and some properties of this enzyme were investigated in mucosal cells of toad bladder. This tissue responds to antidiuretic hormone by an increase in the active transport of Na + , enhancement of permeability to water, urea and certain other small molecules, and by an increase in osmotic water flow across the tissue. These actions of the hormone are all thought to be mediated by adenyl cyclase. Antidiuretic hormones, NaF and Mg 2+ were all found to stimulate the enzyme although the stimulation by Mg 2+ of basal enzyme activity was slight. The hormonal activation was usually greater that of fluoride under optimal conditions. The apparent K m for ATP as derived by measurement of half maximal activity was approx. 1·10 −4 M. Optimal pH was 7·5. At high concentrations both theophylline and, to a lesser extent, cyclic AMP inhibited adenyl cyclase activity. The adenyl cyclase activity was highest in the whole homogenate and the sediment from a 1000 × g centrifugation, results that are in accord with a localization of the enzyme in the cell membrane. Barely detectable activity occurred in the 10 000 × g supernatant. When high concentrations of protein were present in the enzyme assay mixture, inhibition of enzyme activity was observed. The enzyme was labile and deterioration set in when homogenization was too vigorous or prolonged, or when the cells were disrupted by sonication. Ageing of the preparation, even when frozen at −80°, resulted in loss of activity, the loss being more marked for hormonal stimulation than for fluoride stimulation. Divalent cations had marked effects on the enzyme activity. Concentrations of Mg 2+ from 1 to 25 mM had a stimulatory effect upon the enzyme and upon stimulation by hormone and fluoride. Greater concentrations had an inhibitory effect. Ca 2+ was inhibitory at all concentrations above 1·10 −5 M . Thus optimal conditions for the activity of adenyl cyclase have been defined and the preparation should allow further elucidation of the action of hormones on active Na + transport and osmotic water flow in this tissue.
Meteorological Assessment of Homer's Odyssey

Abstract A chronology of the meteorological events described by Homer in the Odyssey following the Achaeans’ conquest of Troy (ca. 1200 B.C.) is developed. Application of polar front theory to the voyages of six separate fleets as they sailed from Troy provides a unique test of the factual nature of a portion of the epic. Nothing beyond the limits of accepted meteorological theory occurred during the first 18 days following the departure from Troy. The Odyssey consistently shows a credible set of weather observations. Evidence suggests that the tragedies experienced by the Achaeans in the Odyssey may have been caused by a cyclonic storm crossing the area in the early summer. If the Achaeans’ initial travels after the conquest of Troy are factual, the chronology developed in this study extends our knowledge of daily weather events to an earlier time than has previously been available and creates a new component in the global history of climate and weather. A description in the Odyssey of a possible microburst...
Implementation-independent model of an instruction set architecture in VHDL

A methodology using a VHDL (VHSIC hardware description language) to create executable models of computer architectures independent of implementation attributes is described. The authors present such a model of a processor architecture known as the WM as the first step in developing an implementation. Simulations using the model can provide performance measurements such as potential parallelism. The model can also serve as an architectural specification for the computer. >
Edge singularities in anisotropic composites

Abstract The stress singularity at the vertex of an anistropic wedge has the form r − ϵ F ( r , θ ) as r → 0 where 0 F is a real function of the polar coordinates ( r , θ). In many cases, F is independent of r . The explicit form of F ( r , θ ) depends on the eigenvalues of the elasticity constants, called p here and on the order of singularity k . When k is real, ξ = k If k is complex, ξ is the real part of k . The p 's are all complex and consist of 3 pairs of complex conjugates which reduce to ± i when the material is isotropic. The function F depends not only on p and k , it also depends on whether p and k are distinct roots of the corresponding determinants. In this paper we present the function F ( r , θ ) in terms of p and k for the cases when p and k are single roots as well as when they are multiple roots. The relationship between the complex variable Z introduced in the analysis and the polar coordinates ( r , θ ) is interpreted geometrically. After presenting the form of F for individual cases, a general form of F is given in eqn (74). We also show that the stress singularity at the crack tip of general anisotropic materials has the order of singularity ξ=1/2 which is at least a multiple root of order 3. The implication of this on the form F ( r , θ ) is discussed.
Adjustment of saccade characteristics during head movements.

Saccade characteristics have been studied during coordinated eye-head movements in monkeys. Amplitude, duration, and peak velocity of saccades with head turning were compared with saccades executed while the head was artificially restrained. The results indicate that the saccade characteristics are modulated as a function of head movement, hence the gaze movement (eye+head) exactly matches saccades with head fixed. Saccade modulation is achieved by way of negative vestibulo-ocular feedback. The neck proprioceptors, because of their longer latency, are effective only if the head starts moving prior to the onset of saccade. It is concluded that saccades make with head turning are not 'ballistic' movements because their trajectory is not entirely predetermined by a central command.
Vortices in Landau-Ginzburg theories of anyonic superconductivity

Abstract We study in detail the structure and properties of vortices in a recently proposed effective Landau-Ginzburg theory of anyonic superconductivity. The theory is described by a Chern-Simons gauge theory interacting with a complex scalar field in a broken symmetry phase. We analyze the profiles for the magnetic field, charge density, electric fie]d and angular momentum in a wide range of parameters between the Abrikosov-Nielsen-Olesen and pure Chern-Simons limits. For small values of the statistical parameter the magnetic field nucleates near the normal core, but is localized away from the core and well into the superconducting region in the Chern-Simons limit. In all cases, the charge density, electric field and magnetic moment density are localized within a ring surrounding the normal core. The unusual properties and quantum numbers of these vortices are studied.
Can we create a viable free open source alternative to magma, maple, mathematica and matlab?

The goal of the Sage project (http://sagemath.org) is to create a truly viable free open source alternative to Magma, Maple, Mathematica and Matlab. Is this possible?
Petrography and palynology of the Blue Gem coal bed (Middle Pennsylvanian), southeastern Kentucky, USA

Petrographic and palynological trends in the Blue Gem coal bed (Middle Pennsylvanian Westphalian B, Breathitt Formation), a thin, low-sulfur, low-ash coal in southeastern Kentucky, were studied in order to establish a depositional model for the seam. Within the study area, the coal bed averages 67 cm and has two distinct zones. The lower and middle parts of the seam (the lower 45–55 cm) are enriched in well-preserved vitrinite and are dominated by arborescent lycopods, sphenopsids, and tree ferns. Fusinite-rich layers, dominated by arborescent lycopods, but also containing herbaceous lycopods and sphenopsids, occur within the lower and middle parts of the seam. The upper part of the seam (the upper 15–25 cm) is recognizable in the field and is distinct in that it contains a greater amount of degraded macerals, and is characterized by high palynomorph diversity, primarily by miospores that are associated with sphenopsids, herbaceous lycopods and arborescent lycopods. These data, in conjunction with geochemical data available for the seam, suggest that initially the peat swamp was fairly diverse and well-nourished (the base of the seam being characterized by a relatively diverse miospore assemblage and a slightly higher ash content). Following this initial planar stage, the Blue Gem peat swamp was probably planar to slightly domed during accumulation of most of the lower and middle parts of the seam, as suggested by the very low ash and sulfur contents, the high telovitrinite content, and the preponderance of arborescent lycopod spores. In its final stages, the peat swamp was domed and is characterized by a more diverse flora and greater levels of degradation of the peat constituents. Sulfur content of this seam is generally low (<1%) but can increase locally to 3–4%. Factors influencing sulfur content include the thickness and nature of the overburden (shale versus sandstone) and petrographic composition.
Establishing the International Acceptability of Fluid Quantity and Flow Rate Measurements (Invited Paper)

Rapid advances in technology-communications, the internet, tele-marketing, travel, etc. are accelerating the globalization of the world’s market places. To facilitate this globalization by eliminating measurement-based barriers to trade, the International Committee on Weights and Measures (CIPM) has, in accord with the authority granted it by the International Treaty of the Meter, produced a Mutual Recognition Arrangement (MRA). This MRA, signed into existence in Oct 1999, has the objectives: 1. to establish the degree of equivalence of national measurement standards maintained by the National Metrology Institutes (NMIs) that have signed the MRA, 2. to provide for the mutual recognition of calibration and measurement certificates issued by the NMIs, and thereby 3. to provide governments and other parties with a secure technical foundation for wider agreements regarding measurements that relate to international trade, commerce, and regulatory affairs. Information on the CIPM, and the MRA can be found on the website: http://www.bipm.org/. Degrees of equivalence between and among national measurement standards are based on the results of Key Comparisons (KCs) conducted within the Consultative Committees of the CIPM. Flow measurement efforts are being addressed by the newly formed Working Group for Fluid Flow (WGFF) of the CIPM Consultative Committee on Mass and Related Quantities (CCM). The WGFF efforts are organized into six, specific measurement areas: water, hydrocarbon liquid, air speed, liquid volume, high pressure gas, and low pressure gas flow. In each of these areas, and according to MRA rules, the efforts are to design and conduct KCs that quantify the equivalence of the flow standards maintained in the participating NMIs. To determine appropriate operating ranges for KC’s, the WGFF is reviewing the Calibration and Measurement Capabilities (CMCs) of the participating NMIs. This presentation will briefly describe the MRA and the current WGFF plans and programs to conduct the KC tests. Specific techniques planned for the KCs will be to design flow meter transfer standards comprised of tandem arrangements of flow meters that are tested in the selected fluid and flow conditions to quantify the performance of NMI flow standards under actual conditions of use. Statistically sufficient and metrologically sound test protocols are being devised to efficiently and effectively produce the required data bases. Youden graphical analysis of variance and other statistical techniques are planned to analyze the resulting data. The results of these WGFF efforts are expected to make it feasible for flow measurements made anywhere in the world to be understood and acceptable anywhere else.© 2002 ASME
009 Differential Phenotypical Expression of Healing vs. Normal Fibroblasts

Fibroblasts from a healing ligament likely have differential phenotypical expression from those in an intact ligament, because fibroblasts at the healing site need to repair/regenerate the wounded matrix around them caused by injury, whereas normal fibroblasts just maintain an intact matrix. This study was designed to determine the differences in proliferation, collagen production, α-smooth muscle actin (α-SMA) expression, and contraction between healing and normal fibroblasts. Transected and sham-operated rat medial collateral ligaments (MCL) were used to obtain healing and normal fibroblasts, respectively. It was noted that healing and normal MCL fibroblasts in culture were seen to have a similar morphology. However, healing fibroblasts in monolayer culture proliferated 1.4-fold faster at 48 hours and had 1.7-fold greater protein expression of α-SMA than normal fibroblasts. In addition, it was noted that the proliferation of healing fibroblasts in collagen gels was not significantly different from that of normal fibroblasts at 24 hours, but it was at 48 hours. Furthermore, in collagen gels, healing fibroblasts produced 10% more type I collagen than normal fibroblasts and generated 1.6- and 1.7-fold larger contractile forces at 15 and 20 hours, respectively, than their normal counterparts. Taken together, the results of this study show that healing fibroblasts possess a differential proliferation, α-SMA protein expression, and contraction than normal fibroblasts. This study also highlights the importance of using healing fibroblasts to study the cellular and molecular mechanisms of ligament healing. Supported by the NIH grant AR049921 and Whitaker Foundation Grant (JHW)
Myocardial contractile reserve on dobutamine echocardiography predicts late spontaneous improvement in cardiac function in patients with recent onset idiopathic dilated cardiomyopathy

Abstract OBJECTIVES The purpose of this study was to determine whether identification of contractile reserve with dobutamine would predict recovery of myocardial function during follow-up in patients with recent onset idiopathic dilated cardiomyopathy (IDC). BACKGROUND The prognosis of patients presenting with new onset IDC is variable and difficult to predict. METHODS Twenty-two patients (17 men, 5 women, 46 ± 14 years) with recently diagnosed IDC (4 ± 3 months) underwent dobutamine echocardiography. Left ventricular ejection fraction (LVEF) and LV sphericity before and at peak dobutamine infusion (30 ± 11 μg/kg/min) were determined. A follow-up echocardiographic assessment was done at 6 ± 4 months. RESULTS The LVEF on dobutamine was directly related to baseline LV mass expressed as g/ml (Pearson r = 0.65, p = 0.0003). Baseline variables that were significantly predictive of follow-up LVEF were deceleration time (r = 0.69, p = 0.0006), wall motion score index (WMSI) (r = −0.63, p = 0.002), LV mass (r = 0.56, p = 0.008) and LVEF on dobutamine (r = 0.84, p = 0.0001). When either deceleration time or WMSI or LV mass was entered into a regression equation to predict follow-up LVEF, the LVEF on dobutamine added significantly to predictive power. However, if LVEF on dobutamine was entered first, none of the other three variables added significantly to prediction. Baseline LV sphericity at end diastole (ED) (r = 0.13, p = 0.6) did not correlate with follow-up LV sphericity in ED, whereas LV sphericity in ED on dobutamine (ED [r = 0.70, p = 0.0004]) correlated with LV sphericity in ED on follow up. CONCLUSIONS This study demonstrates that dobutamine-induced improvement in baseline LVEF and LV sphericity identifies patients with IDC who exhibit substantial improvement in LV function and geometry over time.
Cloning of the O-acetylhomoserine sulfhydrylase gene from the ruminal bacterium Selenomonas ruminantium HD4.

The O-acetylhomoserine sulfhydrylase (OAHS) gene was cloned from a Selenomonas ruminantium HD4 Lambda ZAP II genomic library by degenerative probe hybridization and complementation. Sequence analysis revealed an 869-bp ORF with a G + C content of 53%. The ORF had significant homology with enzymes involved in homocysteine biosynthesis. A CuraBLASTN homology search showed that the ORF has 63% nucleotide identity with the OAHS of Bacillus stearothermophilus, Corynebacterium glutamicum, and Acremonium chrysogenum, and has 58% identity with met25 of Saccharomyces cerevisiae and metZ of Pseudomonas aeruginosa. The deduced amino acid sequence exhibited 45% similarity with Met25 and MetZ. Further analysis predicted that the gene product was a member of the pyridoxal phosphate enzyme family. Complementation experiments with Escherichia coli metA, metB, and metC mutant strains showed that the S. ruminantium OAHS gene can complement the metC mutation and allow for growth on minimal media that contained sodium thiosulfate as the sole source of sulfur. When the OAHS was disturbed by inserting a EZ::TN pMOD-2(Apramycin) transposon, the complementation was lost. Therefore, these results suggest that the gene functions as OAHS in S. ruminantium HD4.
The determination of hot‐water‐soluble boron in some acid Oregon soils using a modified azomethine‐H procedure

Abstract A method is proposed for determination of hot‐water‐soluble boron in acid soils from western Oregon. The soil sample is boiled in 0.02 M CaCl2, filtered, and B determined using azomethine‐H. Soils extracted in this way yielded extracts with little color in them and the predicted error due to this color was 0.00–0.07 ppm B. The use of charcoal as a decolorizing agent resulted in comparatively high predicted errors. Inductively‐coupled plasma emission spectroscopic (ICP) analysis of distilled water and 0.02 M CaCl2 extracts indicated that the extractable B level was not affected by the presence of CaCl2. Azomethine‐H yielded comparable values to ICP but the curcumin method tended to give high values for hot‐water‐soluble B.
Inducible adeno-associated virus-mediated IL-2 gene therapy prevents autoimmune diabetes.

IL-2 and TGF-β1 play key roles in the immunobiology of Foxp3-expressing CD25+CD4+ T cells (Foxp3+Treg). Administration of these cytokines offers an appealing approach to manipulate the Foxp3+Treg pool and treat T cell-mediated autoimmunity such as type 1 diabetes. However, efficacy of cytokine treatment is dependent on the mode of application, and the potent pleiotropic effects of cytokines like IL-2 may lead to severe side effects. In the current study, we used a gene therapy-based approach to assess the efficacy of recombinant adeno-associated virus vectors expressing inducible IL-2 or TGF-β1 transgenes to suppress ongoing β cell autoimmunity in NOD mice. Intramuscular vaccination of recombinant adeno-associated virus to 10-wk-old NOD female mice and a subsequent 3 wk induction of IL-2 was sufficient to prevent diabetes and block the progression of insulitis. Protection correlated with an increased frequency of Foxp3+Treg in the periphery as well as in the draining pancreatic lymph nodes and islets. IL-2 induced a shift in the ratio favoring Foxp3+Treg versus IFN-γ–expressing T cells infiltrating the islets. Induction of IL-2 had no systemic effect on the frequency or activational status of T cells and NK cells. Induction of TGF-β1 had no effect on the Foxp3+Treg pool or the progression of β cell autoimmunity despite induced systemic levels of activated TGF-β1 that were comparable to IL-2. These results demonstrate that inducible IL-2 gene therapy is an effective and safe approach to manipulate Foxp3+Treg and suppress T cell-mediated autoimmunity and that under the conditions employed, IL-2 is more potent than TGF-β1.
Polar electrostatic forces drive poleward chromosome motions

Recent experiments revealing nanoscale electrostatic force generation at kinetochores for chromosome motions have prompted models for interactions between positively charged molecules in kinetochores and negative charge at and near the plus ends of microtubules. A clear picture of how kinetochores and centrosomes establish and maintain a dynamic coupling to microtubules for force generation during the complex motions of mitosis remains elusive. The molecular cell biology paradigm requires that specific molecules, or molecular geometries, for polar force generation be identified. While progress has been made regarding explanations of kinetochore-based chromosome motility, molecular machinery for chromosome poleward movements at centrosomes has yet to be identified. The present work concerns polar generation of poleward force in terms of experimentally known electric charge distributions at microtubule minus ends and centrosomes interacting over nanometer distances.