cssi/SciSciGPT-SciSciNet huggingface dataset:
Spontaneous return of sinus rhythm in older patients with chronic atrial fibrillation and rheumatic mitral valve disease: Description of three patients

Abstract Three patients with rheumatic mitral stenosis had had atrial fibrillation for over ten years before spontaneously restoring normal sinus rhythm. Each had undergone a closed mitral commissurotomy ten to twelve years before the conversion. Their ages at the time of resuming normal rhythm were 47, 59, and 71 years. This unusual phenomenon has no satisfactory explanation by our present knowledge of the natural history of mitral valve disease and the pathogenesis of atrial fibrillation.
Identification of Species in Ground Meat Products Sold on the U.S. Commercial Market Using DNA-Based Methods

Abstract The objective of this study was to test a variety of ground meat products sold on the U.S. commercial market for the presence of potential mislabeling. Forty-eight ground meat samples were purchased from online and retail sources, including both supermarkets and specialty meat retailers. DNA was extracted from each sample in duplicate and tested using DNA barcoding of the cytochrome c oxidase I (COI) gene. The resulting sequences were identified at the species level using the Barcode of Life Database (BOLD). Any samples that failed DNA barcoding went through repeat extraction and sequencing, and due to the possibility of a species mixture, they were tested with real-time polymerase chain reaction (PCR) targeting beef, chicken, lamb, turkey, pork and horse. Of the 48 samples analyzed in this study, 38 were labeled correctly and 10 were found to be mislabeled. Nine of the mislabeled samples were found to contain additional meat species based on real-time PCR, and one sample was mislabeled in its entirety. Interestingly, meat samples ordered from online specialty meat distributors had a higher rate of being mislabeled (35%) compared to samples purchased from a local butcher (18%) and samples purchased at local supermarkets (5.8%). Horsemeat, which is illegal to sell on the U.S. commercial market, was detected in two of the samples acquired from online specialty meat distributors. Overall, the mislabeling detected in this study appears to be due to either intentional mixing of lower-cost meat species into higher cost products or unintentional mixing of meat species due to cross-contamination during processing.
Racking Strength of Light-Frame Nailed Walls

Horizontal forces, such as wind, are resisted by the walls parallel to the wind direction. These forces, which lie in the plane of the wall, are known as the shear or racking loads, and are transmitted to the sheathing through the fastener system. Qualification of sheathing materials has generally been limited to performance testing of 8-ft by 8-ft (2.4-m by 2.4-m) stud wall assemblies. An analytical procedure has been developed that accurately predicts racking strength based upon the lateral resistance of the individual fasteners. The structural model is applicable to any sheathing size or geometry, so it is possible to determine the racking strength of light frame walls from simple lateral nail tests or small scale racking tests. The procedure offers a direct means for designers and code officials to predict racking strengths of panels incorporating various sheathing materials and fasteners.
Thyroid Peroxidase, Thyroglobulin, cAMP and DNA in Human Thyroid

Tissues from normal thyroid, euthyroid multinodular goiter, toxic goiter, Hashimoto's thyroiditis, thyroid adenoma, and carcinoma were examined for their content of deoxyribonucleic acid (DNA), thyroid peroxidase activity (TPA), thyroglobulin (TG), and adenosine 3',5'-cyclic monophosphate (cAMP). Compared with normal thyroids DNA was increased in the neoplastic tissues and decreased in euthyroid multinodular goiter. Quantitative changes of thyroglobulin were observed, especially in the thyroid tumors, and, in one case, immunoreactive 4S thyroglobulin-like protein was identified in the absence of 19S. TPA was grossly elevated in toxic goiter. This may be of significance in the pathogenesis of Graves' disease. TPA remained elevated even after adequate control of hyperthyroidism by preoperative PTU treatment. The cyclic AMP concentration in toxic goiter did not statistically differ from normal. This may indicate that extrathyroidal regulatory factors have a lesser role in the genesis and perpetuation of Graves' disease than otherwise believed. Cyclic AMP is known to exert a negative influence on tissue growth, and low concentrations in neoplasia have been reported. The values in the thyroid tumors studied were elevated, requiring further explanation.
Distribution of latex beads and retinal pigment epithelial cells along the ventral neural crest pathway

Neural crest cells migrate along defined pathways in the trunk of avian embryos. Previous studies have demonstrated that crest-derived pigment cells migrated ventrally after injection onto the ventral neural crest pathway (M. E. Bronner-Fraser and A. M. Cohen, 1980, Develop. Biol. 77, 130–141). In the present study, latex polystyrene beads and retinal pigment epithelial (RPE) cells were injected onto the ventral pathway in order to probe the environment along this migratory route. Although the RPE cells are nonmotile and not derived from the neural crest, they also translocated ventrally. Thus, factors independent of active migration may affect the localization of RPE cells (and endogenous crest cells). To test this possibility, latex polystyrene beads were injected onto the ventral pathway. Three types of beads were used: (a) uncoated latex beads; (b) latex beads coated with bovine serum albumin (BSA-beads); and (c) latex beads coated with fibronectin (FN-beads). Uncoated and BSA-beads distributed along the ventral pathway similarly to RPE cells and endogenous crest cells. However, FN-beads remained near the site of implantation and did not move ventrally. The results suggest (1) that molecules like fibronectin on the cell surface might serve as a recognition mechanism that prevents entrance onto the ventral pathway; and (2) that crest cell localization may, in part, be influenced by a driving force imparted by the embryonic environment.
Complications of transvaginal natural orifice transluminal endoscopic surgery: A series of 102 patients

Objective To review the complications encountered in our facility and in previously published studies of transvaginal (TV) natural orifice transluminal endoscopic surgery (NOTES) to date. Background TV NOTES is currently observed with critical eyes from the surgical community, despite encouraging data to suggest improved short-term recovery and pain. Methods All TV NOTES procedures performed in female patients between 18 and 65 years of age were included. The median follow-up was 90 days. The TV appendectomies and ventral hernia repairs were pure NOTES, through a SILS port in the vagina, whereas TV cholecystectomies were hybrid procedures with the addition of a 5-mm port in the umbilicus. Results A total of 102 TV NOTES procedures, including 72 TV cholecystectomies, 24 TV appendectomies, and 6 TV ventral hernia repairs, were performed. The average age was 37 years old and body mass index was 29 kg/m. Three major and 7 minor complications occurred. The first major complication was a rectal injury during a TV access port insertion. The second major complication was an omental vessel bleed after a TV cholecystectomy. The third complication was an intra-abdominal abscess after a TV appendectomy. Seven minor complications were urinary retention (4), transient brachial plexus injury, dislodgement of an intrauterine device, and vaginal granulation tissue. Conclusions As techniques in TV surgery are adopted, inevitably, complications may occur due to the inherent learning curve. Laparoscopic instruments, although adaptable to TV approaches, have yet to be optimized. A high index of suspicion is necessary to identify complications and optimize outcomes for patients.
Lysozyme release and polymer erosion behavior of injectable implants prepared from PLGA-PEG block copolymers and PLGA/PLGA-PEG blends.

Purpose We evaluated the controlled release of lysozyme from various poly(D,L-lactic-co-glycolic acid) (PLGA) 50/50-polyethylene glycol (PEG) block copolymers relative to PLGA 50/50.
Stereoscopic Photography With a Scanning Laser Ophthalmoscope

Digital fundus angiography has advantages over conventional photography. However, digital angiography as it is normally performed, provides no stereoscopic information. Because stereoscopic data can be crucial in the evaluation of conditions such as age-related macular degeneration, we developed methods to record stereoscopic information during video angiography with a scanning laser ophthalmoscope and to produce high-quality static stereoscopic images. Stereoscopic information was collected by moving the scanning laser ophthalmoscope side-to-side and with a modified Allen separator. Stereoscopic images were displayed as stereoscopic pairs on 35-mm film, stereoscopic pairs from a digital printer, and as stereoscopic images directly on a conventional video monitor. This system to capture and display stereoscopic information is convenient, uses readily available technology, and can be adapted to any digital angiography system.
Measurements of the 10B (n, He) reaction rate in zppr

Abstract Direct measurements of the 10B(n, He) reaction rate have been made in ZPPR. The measurements were made by isotope-dilution mass spectrometric analysis of stainless-steel encapsulated samples of enriched 10B. The results demonstrate that direct measurements of the 10B reaction rate in ZPPR are obtainable to an accuracy of ∼1%. Comparisons with calculations give a predicted-to-experiment value of ∼0.93. This value is consistent with earlier Rockwell measurements in benchmark neutron fields and further supports a need for revision in the ENDF/B cross section for 10B above ∼0.1 MeV.
End user searching on the Internet: an analysis of term pair topics submitted to the excite search engine

Queries submitted to the Excite search engine were analyzed for subject content based on the cooccurrence of terms within multiterm queries. More than 1000 of the most frequently cooccurring term pairs were categorized into one or more of 30 developed subject areas. Subject area frequencies and their cooccurrences with one another were tallied and analyzed using hierarchical cluster analysis and multidimensional scaling. The cluster analyses revealed several anticipated and a few unanticipated groupings of subjects, resulting in several well-defined high-level clusters of broad subject areas. Multidimensional scaling of subject cooccurrences revealed similar relationships among the different subject categories. Applications that arise from a better understanding of the topics users search and their relationships are discussed.
Thalidomide for Patients with Recurrent Lymphoma

BACKGROUND Thalidomide has significant clinical activity in patients with multiple myeloma. However, its activity against other lymphoid tumors is unknown. The authors reported their experience with thalidomide in patients with recurrent/refractory non-Hodgkin lymphoma and in patients with Hodgkin disease. METHODS Nineteen patients (median age, 62 years) who had undergone a median of 5 previous treatment regimens were treated with escalating doses of thalidomide (200–800 mg per day) until disease progression or prohibitive toxicity was observed. The authors measured serum levels of angiogenesis factors before and after treatment. RESULTS One patient (5%) with evidence of recurrent gastric mucosa—associated lymphoid tissue lymphoma achieved a complete response, and 3 patients (16%) achieved stable disease. CONCLUSIONS The current study suggests that thalidomide has limited single-agent activity in heavily pretreated patients with recurrent or refractory lymphoma. Cancer 2004. © 2004 American Cancer Society.
Operational conditions affecting the vaccination of older adults.

Abstract Background The content and context of the process of vaccinating older adults against influenza in outpatient settings has not been adequately described. Failure to appreciate the causal antecedents or precursors to the act of provider recommendation may explain why so many efficacious interventions identified by the U.S. Task Force on Community Preventive Services fail to be routinely implemented and why influenza immunization rates have remained static over the past decade. Methods This study used critical path analysis from data collected during standardized workflow observations of patients more than 50 years of age from a convenience sample of 16 ambulatory care settings in San Diego, California; Rochester, New York; and Albuquerque, New Mexico. Observations were made from October 23, 2001 to January 31, 2002. Results In this study, 62% (151/243) of patients observed during scheduled extended visits received influenza vaccinations. When operational, temporal, and clinical factors are examined altogether through critical path analysis, a model of seven critical organizational support, temporal, and clinical activities emerges that is able to predict 93% of the immunizations. Variation from the model predicts 73% of the missed opportunities. Conclusions Vaccination of adults should not be seen as simply an incremental activity added to the general health encounter. Assuring a high rate of vaccination requires adequate time and operational support. Provider–patient discussion is more productively viewed as the culmination of the immunization process, not the beginning. Finally, this study indicates the potential need to identify and compare processes of care associated with other specific preventive services.
AZYGOS CONTINUATION OF THE CAUDAL VENA CAVA IN A DOG: RADIOGRAPHIC AND ULTRASONOGRAPHIC DIAGNOSIS

Azygos continuation of the caudal vena cava was identified via ultrasonography and angiography in a 7 month old female boxer. Azygos continuation of the caudal vena cava is a rare vascular anomaly that results from failure of anastomosis between the caudal cardinal system and the right vitelline vein during embryogenesis. This anomaly has also been described in association with portoazygos shunt.
Are platelets the link between depression and ischemic heart disease

The role of platelets as the link between ischemic heart disease and depression is reviewed. Platelet function abnormalities, including increased platelet reactivity, may predispose depressed patients to clotting diatheses and may explain their vulnerability to cardiovascular disease. Platelet physiologic characteristics, influences on platelet response, and indicators of platelet reactivity are discussed. Measurements of platelet activation, secretion, and aggregation have enabled the study of platelet responses in patients with major depression. The findings of clinical trials evaluating platelet responses to antidepressant treatment are described, and recommendations for future studies are proposed.
Multiple Identities and the Integration of Personality

Life-history interviews show narrators to shift among multiple, often contradictory self-representations. This article outlines a model that accounts for how a relatively small set of self-symbols and metaphors can form a grammar-like system that simultaneously defines and integrates multiple identities. Drawing on generative theories from linguistics, anthropology, and music, the model proposes that this system provides a unitary deep structure that can be configured in various arrangements to yield multiple surface structures. Each "surface" identity constructs an individual's emotions and social relations--and what he or she accepts as "Me" and rejects as "not-Me"--into a distinct pattern, with identity per se appearing as a dialogic or fugue-like structure of opposed voices. Study-of-lives interviews conducted by the author in urban America and rural Morocco are used to present the model and to demonstrate the pivotal role played by multistable or "structurally ambiguous" symbols in anchoring reversible self-representations which integrate personality as a system of organized contraction. The musical analogy is emphasized in order to build a bridge toward current research in cognitive science and toward efforts to formulate a "state integration" theory of personality development.
Evidence of lasing without inversion in a hot rubidium vapor under electromagnetically-induced-transparency conditions

We report a likely observation of cw lasing without inversion in a gas of hot rubidium atoms in an optical cavity under conditions of electromagnetically induced transparency (EIT). The medium is pumped coherently and resonantly by a single ``coupling'' beam which also produces EIT in the lasing transition. The steady-state intensity exhibits thresholds as a function of the atomic density and the strength of the coupling beam. A theoretical model for an effective three-level lambda system indicates that gain without inversion is possible in this system if the two ground states are coupled by depolarizing collisions, and if the decay branching ratios meet certain conditions.
Thermodynamic stability of Mg-based ternary long-period stacking ordered structures

Abstract Mg alloys containing long-period stacking ordered (LPSO) structures exhibit remarkably high tensile yield strength and ductility. They have been found in a variety of ternary Mg systems of the general form Mg–XL–XS, where XL and XS are elements larger and smaller than Mg, respectively. In this work, we examine the thermodynamic stability of these LPSO precipitates with density functional theory, using a newly proposed structure model based on the inclusion of a Mg interstitial atom. We predict the stabilities for 14H and 18R LPSO structures for many Mg–XL–XL ternary systems: 85 systems consisting of XL = rare earths (RE) Sc, Y, La–Lu and XS = Zn, Al, Cu, Co, Ni. We predict thermodynamically stable LPSO phases in all systems where LPSO structures are observed. In addition, we predict several stable LPSO structures in new, as-yet-unobserved Mg–RE–XS systems. Many non-RE XL elements are also explored on the basis of size mismatch between Mg and XL, including Tl, Sb, Pb, Na, Te, Bi, Pa, Ca, Th, K, Sr—an additional 55 ternary systems. XL = Ca, Sr and Th are predicted to be most promising in terms of forming stable LPSO phases, particularly with XS = Zn. Lastly, several previously observed trends amongst known XL elements are examined. We find that favorable mixing energy between Mg and XL on the face-centered cubic lattice and the size mismatch together serve as excellent criteria determining XL LPSO formation.
Two-Chamber Model for Divertors with Plasma Recycling

To model particle and heat-loss terms at the edge of a tokamak with a divertor or pumped limiter, a simple two-chamber formuluation of the scrapeoff has been constructed by integrating the fluid equations, including sources, along open field lines. The model is then solved for a wide range of density and temperature conditions in the scrapeoff, using geometrical parameters typical of the poloidal divertor in the poloidal divertor experiment (PDX). The solutions characterize four divertor operating conditions for beam-heated plasmas: plugged, unplugged, blowthrough, and blowback.
Implementation of imaging technology for recordkeeping at the World Bank

Cet article decrit l'evolution d'un systeme de gestion de documents electroniques comprenant le stockage des documents implemente a la World Bank, une organisation internationale qui se trouve a Washington D.C. et qui a des bureaux dans de nombeux pays. De plus cet article montre comment les besoins de Pittsburgh ont ete utilises pour evaluer ce systeme lors de ses developpements
High-resolution, anamorphic, adaptive small-animal SPECT imaging with silicon double-sided strip detectors

We are developing a prototype gamma-ray imaging system that consists of two sets of movable, keel-edged copper-tungsten blades configured as crossed slits. These apertures can be positioned independently between the object and detector, producing an anamorphic image in which the axial and transaxial magnifications are not constrained to be equal. The detector is a 60 mm x 60 mm, millimeter thick, one-megapixel silicon double-sided strip detector. The flexible nature of this system allows the application of adaptive imaging techniques. We will discuss system details, calibration and acquisition methods, and our progress towards biological imaging applications.
Invited paper A unified theory for MOS circuit design—switching network logic

ABSTRACT The switching network logic (SNL) design method is introduced. It is a systematic approach to the design of MOS circuits based on the switching network concept. The double-rail SNL and single-rail SNL are discussed in which the single-rail SNL makes efficient use of the negation property of MOS circuits. The SNL circuits have better performances than those of MOS circuits designed with NAND-NOR-gate or negative-gate approaches. Moreover, the SNL circuit is guaranteed to be minimal for SC and SP functions.
Evidence for a New Viral Late-Domain Core Sequence, FPIV, Necessary for Budding of a Paramyxovirus

Enveloped virus budding has been linked to both the ubiquitin-proteasome pathway and the vacuolar protein-sorting pathway of cells. We show here for the paramyxovirus SV5 that proteasome inhibitors and expression of dominant-negative VPS4(E228Q) ATPase blocks budding. The SV5 matrix (M) protein lacks previously defined late domains (e.g., P[T/S]AP, PPxY, YPDL) that recruit cellular factors. We identified a new motif for budding (core sequence FPIV) that can compensate functionally for lack of a PTAP late domain in budding human immunodeficiency virus type 1 virus-like particles (VLPs). Mutagenesis experiments suggest the more general sequence O-P-x-V. The proline residue was found to be critically important for function of this sequence, as substitution of this proline in the SV5 M protein resulted in poor budding of SV5 VLPs and failure of recombinant SV5 virus to replicate normally. Adaptation of mutant virus occurred rapidly, resulting in new proline residues elsewhere in the M protein. We hypothesize that these proline residues act to partially restore virus budding by generation of new motifs that act as suboptimal late domains.
Establishing an Animal Model for the Evaluation of Vaginal Meshes

Roughly three million women in the United States give birth vaginally each year [1]. Clinically, the vagina undergoes pronounced adaptations up to the time of delivery, presumably to afford passage of the fetus [2]. Our group has suggested that if these adaptations are not sufficient or if fetus size is too large, an injury to the vagina or its supportive tissues will likely result. Vaginal injury at the time of delivery occurs quite frequently and research examining the levator ani muscle, the major muscular component of the pelvic floor, revealed injury in up to 20% of women who have given birth vaginally [3]. Therefore, vaginal birth is considered one of the greatest risk factors for pelvic floor disorders (i.e. urinary dysfunction and pelvic organ prolapse) later in life.Copyright © 2009 by ASME
Lipodystrophies: Genetic and Acquired Body Fat Disorders

Context: Lipodystrophies are heterogeneous, genetic or acquired disorders characterized by selective loss of body fat and predisposition to insulin resistance. The extent of fat loss determines the severity of associated metabolic complications such as diabetes mellitus, hypertriglyceridemia, and hepatic steatosis. Evidence Acquisition and Synthesis: Both original and review articles were found via PubMed search reporting on clinical features and management of various types of lipodystrophies and were integrated with the author's knowledge of the field. Conclusion: The autosomal recessive congenital generalized lipodystrophy and autosomal dominant familial partial lipodystrophy (FPL) are the two most common types of genetic lipodystrophies. Mutations in AGPAT2, BSCL2, CAV1, and PTRF have been reported in congenital generalized lipodystrophy and in LMNA, PPARG, AKT2, and PLIN1 in FPL. CIDEC is the disease gene for autosomal recessive, FPL and LMNA and ZMPSTE24 for autosomal recessive, mandibuloacral dyspla...
The effect of protein adsorption on the friction behavior of ultra-high molecular weight polyethylene

Medical-grade UHMWPE samples with two different surface finishing treatments, milling and melting/reforming were exposed to 10% bovine serum albumin solution and their friction responses were quantified using atomic force microscopy. The observed friction increase upon exposure to proteins was attributed to the formation of a layer of denatured proteins on the surface. Changing the crystallinity and surface energy of UHMWPE affected the protein adsorption mechanism and the resulting increase in friction behavior.
Limited-access surgical coronary artery revascularization.

Abstract The continued evolution of surgical revascularization has resulted in much less invasive alternatives for patients undergoing coronary artery bypass grafting. In particular, techniques and technologies have been developed to allow for the grafting of coronary arteries through limited access incisions without the circulatory support of cardiopulmonary bypass. The conduits are generally arterial rather than the venous alternatives used originally, and the harvesting of these conduits is performed through limited access incisions described in another article in this review. The result of these efforts is sternal-sparing solutions for the off-pump coronary artery bypass grafting of all the various coronary locations on the heart. This is accomplished through a spectrum of small incisions that can directly expose any specific area of interest for focal bypass grafting. The surgical insult is greatly reduced and the patient's recovery is significantly enhanced. These efforts continue to bring us closer to the ultimate goal of 24-hour hospital stays for coronary artery bypass grafting patients. Copyright 2002, Elsevier Science (USA). All rights reserved.
Protective factors and suicide risk in adolescents with a history of sexual abuse

Objective To test the hypothesis that certain protective factors will reduce the risk of suicide behaviors in youth who are sexually abused. Study design Survey data come from 83,731 students in the 6th, 9th, and 12th grades in Minnesota. Four childhood sexual abuse groups were created: a) no history of sexual abuse; b) abuse by non-family member; c) abuse by family member; and d) abuse by both. Dependent variables included suicidal ideation and attempts. Four protective factors included: family connectedness, teacher caring, other adult caring, and school safety. Logistic regression was used in detecting differences in suicide behaviors across the 4 childhood sexual abuse categories. Results Four percent of students reported sexual abuse by a non-family member, 1.3% by a family member, and 1.4% by both. Although youth with a history of childhood sexual abuse were at increased risk for suicide behaviors compared with other youth, when protective factors were accounted for, the predicted probabilities of suicide behaviors for childhood sexual abuse youth were substantially reduced. Family connectedness was the strongest of the 4 protective factors. Conclusion Modifying select protective factors, particularly family connectedness, may reduce suicide risk in adolescents with childhood sexual abuse.
Origin of Martian Channels: Clathrates and Water

Criticism is directed at the suggestion that Martian channels may have been eroded by liquid water produced by the depressurization of CO2 hydrate. The release of pre-existing subsurface liquid water, such as that trapped under a permafrost layer, by meteorite impact or tectonic activity could produce sufficient flow and would not require heat transfer. The presence of water in a CO2 hydrate is shown to be detrimental to its release from an underground reservoir.
Solar source regions of coronal mass ejections and their geomagnetic effects

Abstract It is generally accepted that the fast interplanetary manifestations of coronal mass ejections (ICMEs) are the major solar drivers of many space weather phenomena, including large, non-recurrent geomagnetic storms and solar energetic particle events. High-quality synoptic observations of the solar corona, as carried out by the EIT and LASCO experiments on SOHO, provide near real-time imaging of CMEs from the base of the corona out to a projected distance of 30 R ⊙ ( R ⊙ is the solar radius). The average characteristics of CMEs observed by LASCO are similar to those from earlier coronagraphs. Most CMEs travel with approximately constant speed through the LASCO field of view. However, a significant number accelerate as they move outward, and some fast events have been observed to decelerate. LASCO has observed a great deal of internal structure in many CMEs. Concave-outward structures that are interpreted as magnetic flux ropes are observed in approximately one third of all events. Complex structures are often observed in the trailing portions of CMEs. Halo CMEs, many of which are very faint, can be routinely observed with LASCO. Extreme-ultraviolet (EUV) images of the low corona and solar disk, as recorded by EIT, reveal a complex web of CME signatures. These include large-scale waves in the inner corona associated with CMEs, extended regions of depleted EUV intensity, and bright arcades that form following the occurrence of a CME. The combination of LASCO and EIT imagery allows the source regions of halo CMEs to be identified, and can be used to help predict the occurrence of geomagnetic disturbances several days in advance. The most important parameters in determining the geoeffectiveness of an ICME are the magnetic field strength and direction, and the speed of the disturbance. The most intense geomagnetic storms are associated with strong and persistent southward fields, either within the ICME itself or in the compressed sheath of solar wind plasma ahead of it.
Track Stiffness Transition Zone Studied with Three-Dimensional Sandwich Track Model

When railroad tracks pass from an earthen subgrade to a bridge, the tracks become uneven. In fact, even if the tracks are level at the time of construction, over time a dip develops. This phenomenon occurs just in front of the bridge and is a cause of greater maintenance and poor ride quality. The track before bridges typically needs to be resurfaced more frequently; this maintenance increases the cost for a railroad owner. The cause for this dip in the track is believed to be the sudden change in stiffness between the subgrade and the bridge. The most commonly used approach to neutralize this sudden stiffness change is called the stiffness transition zone method. The idea is to spread out the stiffness jump from a few centimeters to the length of about 30 m by gradually changing the stiffness of the track. However, the details of the stiffness transition zone—for instance, the length, the pattern of the stiffness change, and the effect of train speed—have yet to be studied. A dynamic track model called t...
The Pleasance of Poetry

P o e try is th e o ld e s t o f a l l th e c o m p o n e n ts o f h u m a n le a rn in g . T h ro u g h o u t th e ages o f m a n it has be en a s a lie n t p a r t o f th e c u ltu re o f a ll p e o p le s . I t is th e m o s t v a lu a b le segm en t o f o u r l i te r a r y h e rita g e , a p re c io u s in h e r ita n c e f o r th e re a d e rs w h o d e r iv e f r o m its tre a su re s a fu n d a ­ m e n ta l in te rp re ta t io n o f th e e te rn a l va lu e s o f l i fe an d th e ir re le v a n c e to th e liv e s o f a l l m en . F r o m th e l i t t le c o m m o n th in g s to th e im m e n s e ­ ness o f th e c o sm o s , p o e try re f le c ts an e x p a n ­ s iv e a w a re ness o f a l l th e fa ce ts o f m a n ’ s th in k ­ in g a n d d o in g in h is e n v iro n m e n t o f th e fa m il ia r an d u n fa m il ia r , th e k n o w n an d th e u n k n o w n . T o E m e rs o n , th e p o e t “ is th e s a ye r, th e n a m e r, a n d re p re se n ts b e a u ty . . . a b e h o ld e r o f id e a s .” C o le r id g e c ite d th e e sse n tia l p u rp o s e o f th e p o e t: “ so to re p re s e n t fa m il ia r o b je c ts as to a w a k e n in th e m in d s o f o th e rs a k in d re d fe e lin g to w a rd s th e m .” I n h is P re fa c e to th e L y r ic a l B a lla d s , W o rd s w o r th w ro te c la s s ic a lly a b o u t th e p o e t:
Tensile properties of potato tubers

Mechanical properties of Kennebec and Russet Burbank potato tubers were computed from Force-elongation data on specimens cut from the tuber and tested in tension. Specimens cut from three locations in fresh and stored tubers were tested at varying strain rates at 70 F (21 C) and at 42 F (6 C). Results were analyzed for significant differences. Tests were conducted in 1964 and 1966. In spite of some differences in tuber condition and test and analysis methods, there was good agreement of results between the years. Mean values of properties for all tests were: tensile strength, 98 psi; strain at failure, 0.193 in./in.; and failure modulus (stiffness), 727 psi. Properties varied greatly with location in the tuber. The pith, in the center, is stronger and stiffer than the perimedullary zone surrounding it, and the skin-cortex exhibits different properties than either of these two. Storage affected properties at the skin and in the center much more than in the perimedullary zone. As strain rate increased, tensile strength and stiffness generally increased, and strain at failure decreased. Stiffness generally increased when temperature decreased. Effect of variety was mixed. One of the greatest problems in designing and using potato handling and processing equipment is damage to the potatoes. This lowers their market value and increases their susceptibility to disease and deterioration in storage. Various investigators, by dropping or hitting tubers experimentally or by following them through normal hanlling operations, have determined the external causes of damage to whole tubers and conditions that promote it. These experiments have yielded much needed information, but they tell little about the properties of th tubers that make them so susceptible to injury. Finney (2) and Timbers (7) have attempted to determine some of the mechanical properties of potato tubers and report them in engineering terms. This type of approach is necessary for an understanding of the behavior of potatoes in handling and processing operations. The purpose of this study is to determine mechanical properties of potato tuber tissue and report them in terms that will be usable by people who do further work in this area. Because at least some cracks in potatoes are caused by failure in tension, and because no record of tests on potato tissue in tension was found, these tests were conducted on specimens of potato tuber in tension.
Nitroxide-Mediated Living Free Radical Miniemulsion Polymerization of Styrene

The miniemulsion technique was applied to the controlled/living free radical polymerization of styrene utilizing TEMPO-terminated oligomers of polystyrene (TTOPS) as a macroinitiator species to initiate the polymerization at 125 °C. Miniemulsion polymerizations of styrene using different amounts of TTOPS were studied. It was found that the polymerization rate of a miniemulsion containing no TTOPS was significantly faster than those containing TTOPS. In the latter reactions, the molecular weight of the polymer increased almost linearly with conversion up to 75% conversion. The slope of the molecular weight vs conversion curve increased with decreasing TTOPS concentration as expected. Particle size distributions were measured by both TEM and CHDF and were found to be broad. Using the kinetics and particle size data, the average number of active free radicals per particle (n in classical emulsion polymerization systems) was estimated and found to be low (≤0.005).
Regulatory roles for histone deacetylation in IL‐1β‐induced nitric oxide release in pancreatic β‐cells

Histone (de)acetylases control gene transcription via modification of the chromatin structure. Herein, we investigated potential roles for histone deacetylation (or hypoacetylation) in interleukin-1β (IL-1β)-mediated inducible nitric oxide synthase (iNOS) and nitric oxide (NO) release in insulin-secreting INS 832/13 (INS) cells. Western blot analysis suggested localization of members of Class 1 and Class 2 families of histone deacetylases (HDACs) in these cells. Trichostatin A (TSA), a known inhibitor of HDACs, markedly reduced IL-1β-mediated iNOS expression and NO release from these cells in a concentration-dependent manner. TSA also promoted hyperacetylation of histone H4 under conditions in which it inhibited IL-1β-mediated effects on isolated β cells. Rottlerin, a known inhibitor of protein kinase Cδ, also increased histone H4 acetylation, and inhibited IL-1β-induced iNOS expression and NO release in these cells. It appears that the putative mechanism underlying the stimulatory effects of rottlerin on acetylation status of histone H4 are distinct from the HDAC inhibitory property of TSA, since rottlerin failed to inhibit HDAC activity in nuclear extracts isolated from INS cells. These data are suggestive of potential regulatory effects of rottlerin at the level of increasing the histone acetyltransferase activity in these cells. Together our studies present the first evidence to suggest a PKCδ-mediated signalling step, which promotes hypoacetylation of candidate histones culminating in IL-1β-induced metabolic dysfunction of the isolated β cell.
GROWTH OF THE MALE GUINEA PIG MAMMARY GLAND WITH DIETHYLSTILBESTROL1,2

GROWTH OF THE MAMMARY GLAND with hormone treatment has been exten-sively studied in the guinea pig. Crude lipid extracts of placentae, ovaries and corpora lutea were reported to develop ducts or complete lobule'alveolar systems and to cause secretion in some cases in virginal, parous and castrate females and in normal, castrate and immature males (see Turner, i, for review). More recently purified and crystalline estrogens at low dosages have been shown to develop both mammary ducts and complete lobule'alveolar systems equal to that observed at the time of pregnancy (2, 3, 4). The guinea pig thus differs from other laboratory rodents in that complete mammary development can be readily obtained with estrogens in-jected for short periods of time at low dosages.
The geographic impact of ‘open skies’ policies on Trans-Tasman air passenger service

: The goal of this paper is to examine the various geographic shifts occurring in New Zealand air passenger service as a result of the liberal aviation policies pursued by the country. A brief history of New Zealand air passenger travel both domestically and internationally will be followed by a more in-depth investigation into the impacts of the single aviation market between New Zealand and Australia, first negotiated in 1992, subsequently altered in 1996 and, in its present form, agreed to in 2000. Particular attention is given to the increased competition that has arisen in the Trans-Tasman market, making it one of the most heavily contested routes in global aviation. The Trans-Tasman is analysed at a variety of levels, including airline competition, market growth, and fare changes that have occurred in the five years since the ‘full open skies’ agreement came into effect.
Customs union and unemployment in LDCs

Abstract Welfare effects of customs union are examined for a small open economy with unemployment of labor of Harris-Todaro type and some new results are reported. Specifically, it is demonstrated that for LDCs afflicted with urban unemployment, trade-creating customs union continues to be an effective policy.
Comparison of the Characteristics and Functioning of Cocaine Treatment and Cocaine Research Subjects

Comparisons were made of the functioning and characteristics of cocaine-abusing volunteers to a research ward (N = 25) and to an outpatient treatment program (N = 33) at the same research facility. It was hypothesized that individuals volunteering for clinical studies and for treatment-related studies would represent different segments of the cocaine-abusing population, and that those differences could be significant to an understanding of study findings. Demographic/background variables were assessed through use of the Addiction Severity Index, risk-taking behaviors relative to HIV infection and AIDS through use of a structured interview schedule, intellectual functioning through use of the Shipley Institute for Living Scale, and psychiatric symptoms through use of the Hopkins Symptom Check List (SCL-90R). Significant differences were obtained for criminal activity, needle sharing, and selected psychiatric symptoms. Marital status was particularly important to an understanding of differences between rese...
Long‐term effects of pancreatic transplantation on diabetic neuropathy

Restoration of a long-lasting euglycemic state by a functioning pancreatic transplantation (PTx) is the most logical treatment for insulin-dependent diabetes mellitus and for amelioration of secondary complications, including neuropathy. We evaluated neurological function by clinical examination, nerve conduction studies, and autonomic function tests in 115 patients with a functioning PTx and in 92 control patients treated with insulin, at baseline and 1, 2, 3.5, 5, 7, and 10 years later. In control patients, neuropathy progressively worsened during follow-up. The clinical examination score and composite indices of abnormality of motor and sensory nerve conduction decreased significantly at all intervals tested. Autonomic function indices also decreased, but significantly only after 1 year. In patients who received a successful PTx the neuropathy improved. The motor and sensory nerve conduction indices increased significantly at all intervals after transplantation, whereas the clinical examination and autonomic tests improved only slightly. Patients who received either a PTx alone, a PTx after a kidney graft, or simultaneous pancreatic and kidney transplantations improved similarly over the follow-up. These results indicate that a functioning PTx halts the progression and improves the signs of diabetic polyneuropathy by restoration of a normoglycemic state.
Social Psychology as Both Science and History

In a brief discussion of some of the issues concerning the nature of social psychology which have been raised in recent articles by Gergen, Schlenker, Manis, and Thorngate, it is argued that there is a view about the nature of social psychology which takes advantage of and to some extent reconciles both Gergen's arguments for social psychology as history and Schlenker's argu ments for social psychology as science.
Hunger and river basin development in Africa: Some socioeconomic issues

New concerns with African drought and famine have redirected attention to the great potential of African rivers dramatically to increase food production. The recent history of irrigation, however, has proved otherwise. This is partly due to policy makers' failure systematically to consider the socio-economics of land/water use in river basins in their development plans. This paper focuses on the socioeconomic dimensions of African river basin development and argues that a better incorporation of such systems in development plans will aid African countries more effectively to achieve their food production and development goals.
Fourier Optics And Pattern Recognition

In Fourier optics, the Fourier transformation is performed on the amplitude of the electromagnetic wave, whereas in the computational method the transformation is usually applied to the grayness of its image which is proportional to the intensity of the electromagnetic signal.
Systems thinking during systems analysis and design

A number of academicians and practitioners have called for more systems thinking. In this subjective essay I examine elements of systems thinking that are and are not likely to be taught in the education of systems analysts. My purpose is to understand the elements of systems thinking that potential systems analysts learn. Since no definitive model of systems thinking exists, I first summarize the elements of systems thinking in five alternative models of systems thinking extant in the literature -- general systems approach and complexity theory, cybernetics, system dynamics, soft system methodology, and critical systems theory and multimethodology -- and then examine which of those elements are included in Systems Analysis and Design textbooks. The findings indicate that what is likely to be taught is an approach to understanding and designing an information system that decomposes the system into component parts that interrelate through processing input data into outputs. This reductionist approach also includes an understanding of the information system's boundary, which determines system scope. What is unlikely to be taught, besides the five alternative models of systems thinking, are the general system concepts of synergism, negative entropy, dynamic equilibrium, internal elaboration, multiple goal-seeking, and equifinality of open systems. With this foundation I encourage IS faculty to engage in a continuing dialog on what elements of systems thinking potential systems analysts should learn.
A new model for SOS-induced mutagenesis: how RecA protein activates DNA polymerase V

In Escherichia coli, cell survival and genomic stability after UV radiation depends on repair mechanisms induced as part of the SOS response to DNA damage. The early phase of the SOS response is mostly dominated by accurate DNA repair, while the later phase is characterized with elevated mutation levels caused by error-prone DNA replication. SOS mutagenesis is largely the result of the action of DNA polymerase V (pol V), which has the ability to insert nucleotides opposite various DNA lesions in a process termed translesion DNA synthesis (TLS). Pol V is a low-fidelity polymerase that is composed of UmuD′2C and is encoded by the umuDC operon. Pol V is strictly regulated in the cell so as to avoid genomic mutation overload. RecA nucleoprotein filaments (RecA*), formed by RecA binding to single-stranded DNA with ATP, are essential for pol V-catalyzed TLS both in vivo and in vitro. This review focuses on recent studies addressing the protein composition of active DNA polymerase V, and the role of RecA protein...
Logic for morals, morals from logic

The need to distinguish between logical and extra-logical varieties of inference, entailment, validity, and consistency has played a prominent role in meta-ethical debates between expressivists and descriptivists. But, to date, the importance that matters of logical form play in these distinctions has been overlooked. That’s a mistake given the foundational place that logical form plays in our understanding of the difference between the logical and the extra-logical. This essay argues that descriptivists are better positioned than their expressivist rivals to provide the needed account of logical form, and so better able to capture the needed distinctions. This finding is significant for several reasons: First, it provides a new argument against expressivism. Second, it reveals that descriptivists can make use of this new argument only if they are willing to take a controversial—but plausible—stand on claims about the nature and foundations of logic.
Microcracking in Large-grain Al2O3

Abstract The critical grain size for microcracking in Al2O3 was estimated to be 70 μm by a method, based on fracture mechanics, which predicts a linear relationship between the temperature TMB at which microcracking begins and the reciprocal square root of the grain size. TMB was interpreted as the temperature at which, on cooling, the relation between Young's modulus and the temperature departed from the expected linear behavior.