cssi/SciSciGPT-SciSciNet huggingface dataset:
Elasto-plastic impact on rigid targets.

The general purpose of this investigation is to determine the dynamic behavior of metallic materials (particularly, influence on the yield stress) through the study of the deformation of a projectile during the process of penetration. The method of approach known as direct analysis has been used. This method bypasses differential equations and instead directly uses the physical laws of the process. This paper is divided into two parts. In the firstjof these, we assume rigid, perfectly plastic behavior at a specified yield stress. In the second part, the analysis is extended to take into account more general material behavior. Itfincludes the effect of elasticity and various combinations of work-hardening. Two groups of comparison studies were made, first with the results of A. C. Whiffin and G. I. Taylor, and then with some recent data of Ballistic Research Laboratory (BRL) projectiles. It has been found that this analysis can give very satisfactory agreement with the actual profiles (for mild steel) if we assume a rigid work-hardening behavior.
RAZÓN DE POSIBILIDADES: UNA PROPUESTA DE TRADUCCIÓN DE LA EXPRESIÓN ODDS RATIO

In English, odds ratio is a basic epidemiological measure approximating the relative risk. Odds ratio has been translated into Spanish in several ways, which has produced great terminological confusion. On the other hand, the English word odds is often used in epidemiology or statistics English textbooks, alone or as part of other expressions, but always keeping a definite mathematical meaning, which calls for a similarly definite term in Spanish. We discuss several translations of odds ratio found in the literature and propose the Spanish word "posibilidades" as a translation of odds and "razon de posibilidades" as a translation of odds ratio.
High-level free-carrier injection in advance bipolar junction transistors

This paper presents a comprehensive study on the effects of high-level free-carrier injection on the current transport of bipolar junction transistors (BJTs). Detailed information for the free-carrier concentration, electric field, and drift and diffusion current components in the quasi-neutral base (QNB) under high-level injection are calculated using the modified ambipolar transport equation and using several different approximations for the majority-carrier current in the QND. It is shown that high-level injection can create a large retarding field which is in the opposite direction of the built-in field associated with the nonuniform doping concentration. High-level injection also enhances recombination in the QNB, thus resulting in a position-dependent minority-carrier current in the region even if the base is thin. Our results further suggest that the widely used zero majority current approximation gives rise to a larger error compared to other lesser known approximations.
The Mobile Phone Store Ecology in a Mumbai Slum Community: Hybrid Networks for Enterprise

We report on an ethnographic study of mobile stores’ business practices in a slum community in Mumbai. The basic mobile phone store that sells small “talktime” (the period of billing per call) is graduating to repair, formatting, and maintenance of phone hardware and software. Central to this process of store expansion and skill building is the store entrepreneur. He forges relations with procurement channels and mediating agents, renewing existing ties and expanding business loops by interweaving social and business networks. We refer to these aggregations as “hybrid networks,” and we highlight their maintenance as a critical resource governing enterprise potential. By evoking the ecology of the mobile phone business in an urban slum setting, the paper draws attention to the following concepts: 1) the unique potential of ICTs as an entrepreneurial commodity, 2) the micro- and small enterprise (MSE) as a functional model for local technology immersions, and 3) local social networks as pivotal in expanding technology adoption and aligning with the needs of the low-income consumer. In essence, we locate the small mobile phone store as the site of convergence for the commercial expansion of mobile phone technology.
Green polypropylene/waste paper composites with superior modulus and crystallization behavior: Optimizing specific energy in solid-state shear pulverization for filler size reduction and dispersion

Abstract Solid-state shear pulverization (SSSP) is a continuous process that overcomes challenges in producing well-dispersed polymer composites that cannot be made by twin-screw melt extrusion. We use SSSP to produce 85/15 wt% polypropylene/waste paper biocomposites with polypropylene pellets and 2-cm-square waste paper pieces as starting material. Single-pass SSSP achieves effective filler size reduction and dispersion within the polypropylene matrix. We determine how waste paper size reduction and composite properties are functions of specific energy input and tune specific energy input by SSSP screw design and throughput. Composites made at moderate to high specific energy input (14–35 kJ/g) have 25 to nearly 50% of filler particles at sub-micron size; relative to neat polypropylene, composites exhibit a 70% increase in Young’s modulus, retention of neat polypropylene yield strength, and a ∼50% reduction in crystallization half-time. Estimates indicate that the cost of such biocomposite materials made by SSSP is less than that of virgin polypropylene.
Physical Features of Some Turkish Carob (Ceratonia siliqua L.) Pods

The carob tree (Ceratonia siliqua L.) has been grown mainly in Spain, Italy, Portugal, Greece, Cyprus, Morocco, Turkey, Israel, Algeria, and Tunisia. It is used for different purposes mainly in the areas of industry, afforestation, prevention of soil erosion, ornamental and human nutrition, and animal feed. Carob pods consist of two important parts. “Carob Kibbles” or the remaining pulp are used for animal and human nutrition, raw materials for industrial processing. “Carob Kernel” or seeds are very important for Locust Bean Gum industry. The objective of this study was to evaluate some of the physical characteristics of Turkish carob pods. Two domestic types (types 42 and 72) and two wild types (types 2 and 88) were used in this study. The study was carried out in 2008. Fruit samples were collected from the trees when the moisture content of pods was 14-15% of fruit weight. For pod features; fruit weight, length, diameter, and thickness, flesh weight, fruit ratio and for seed features; number of seeds, seed weight and seed ratio were measured. The highest fruit weight, fruit length, fruit width, fruit thickness, husk weight, and husk percentage were found in e types 42 and 72. However, seed number and seed percentage of wild types (type 2 and 88) were found to be greater than those of both domestic types (types 42 and 72). Average fruit weight, length and width ranged from 7.45-36.25 g to 17.00-18.50 cm and 1.93-2.53 cm, respectively. Types 2 demonstrated the highest seed percentage (24.26%). The carob fruit, seed yield and quality have a very high importance to the industry. Therefore, these traits can be useful breeding tool traits to breed a suitable commercial carob genotype for high fruit yield and seed quality.
Cyanogenic glycosides content in two edible leaves of tree spinach (Cnidoscolus spp.)

Abstract The cyanogenic glycosides content (ranging from 0.79±0.2 to 14.79±0.4 μg HCN equivalent/g fresh wt) of two edible tree spinach (Cnidoscolus chayamansa McVaugh and C. aconitifolius (P. Mill.) I.M. Johnston) leaves was quantitatively analyzed using enzymatic assay and UV-vis spectrum techniques. Both techniques equally show efficiency and reliability in assessing cyanogen content in tree spinach vegetable tissues. Cyanogenic glycoside concentration was significantly ( P 0.05 ) higher in frozen leaf samples of C. chayamansas, when compared to fresh leaf samples. The principal form of cyanogenic glycosides in the edible Cnidoscolus leaves was identified as linamarin using high performance thin layer chromatography.
Intensity-reversal in the donor bound exciton luminescence of GaAs

Abstract A self-reversal model is presented to explain the luminescence dependence of the donor bound exciton intensity. The line broadening mechanism is attributed to rotational interaction with non-rigid rotator states. Line reversal results from absorption by non-broadened states near the crystal surface. The absence of a similar excitation intensity dependence for acceptor bound excitons is explained.
Profiling bankamericard (visa) and master charge holders

Recently, legislation affecting the granting of credit, and the desire of many banks to become dual issuers of the two national bank cards (Bank Americard (Visa) and Master Charge), have created a need for more information about bank credit cards and the holders of either or both of these two national cards. Both bankers and retailers are interested in knowing more about the market segments holding one or both of these cards, and whether or not there is any difference in theusage of credit between holders of either or both cards. This paper compares the socioeconomic characteristics, attitudinal response, and credit usage of a nationwide probability sample of Americans who possess one or both of these two national bank credit cards.
The influence of zinc on the ontogeny of hepatic metallothionein in the fetal rat.

The ontogeny of hepatic metallothioneins (Mt) in fetal tissue as related to dietary and hepatic Zn was investigated. Sixty 6-month-old female rats were divided into two groups and given either double-distilled water or water containing 700 )g of Zn per milliliter. Dams from each group were killed on 16, 19, or 21 days of gestation, and maternal and fetal livers were removed. Mt content of the tissue was estimated by Piotrowski's Hg-saturation method. Results established the presence of an endogenous hepatic Mt in the fetal rat as early as 16 days of gestation. We further demonstrated a marked progressive increase in fetal Mt from Day 16 through gestation accompanied by a decrease in maternal hepatic Mt. It is suggested that Zn increased fetal Mt by inducing fetal synthesis, redistributing fetal Mt, or increasing Mt transport to the fetus, because both fetal and maternal hepatic Mt were increased. Fetal hepatic Mt concentration was several times greater than maternal Mt at corresponding stages of gestation. Mt may serve to either ensure adequate storage of Zn or Cu for fetal development or protect the fetus against metal toxicity, but the significance of these high endogenous levels of fetal Mt are not clear atmore » this time.« less
Landscape Patterns of Forb Pannes Across a Northern New England Salt Marsh

Most salt marshes are dominated by graminoids, but patches dominated by a diverse assemblage of perennial forbs, known as forb pannes, occur on marshes in north temperate areas. These pannes and their associated species diversity appear to be highly responsive to anthropogenic change, including climate warming. We mapped all of the forb pannes on a salt marsh in Wells, Maine in order to 1) determine if geospatial features were related to panne location and species composition, and 2) record a baseline to compare with future responses to anthropogenic change. Forb pannes occupied approximately 5% of the high marsh surface, with sizes ranging from 7 m2 to 5000 m2. Pannes themselves were clustered at river/creek edges and near pools. Within pannes, species diversity was highest away from pools and the river mouth, and relative abundance of Plantago maritima was related to spatial variables. These results suggest that forb panne distribution and community structure are influenced by spatial variables and reinforce the notion that forb pannes may be used to track salt marsh responses to global change.
Anesthesia for functional neurosurgery: the role of dexmedetomidine.

Purpose of reviewThe purpose of this review is to summarize current approaches to the anesthetic management of functional neurosurgery and to describe the application of an α-2-adrenergic agonist dexmedetomidine in the anesthetic management of functional neurosurgical procedures.Recent findingsDexme
Measured particulate behavior in a subscale solid propellant rocket motor

Particle size distributions were measured in the combustion chamber, exhaust nozzle, and exhaust plume of a small, two-dimensional rocket motor that utilized aluminized propellants. Various nozzle contours and pressures to 4.36 MPa were utilized. For pressures less than approximately 2.4 MPa, D32 of the multimodal size distributions entering the nozzle decreased with increasing pressure. Above 2.4 MPa, the higher propellant burning rates significantly reduced particle agglomeration and increased C* efficiency. At higher pressures, D32 entering the nozzle was quite small (2-6 /u.) and monomodal, and did not vary appreciably with pressure. During tailoff, D32 was significantly larger than during the steady burn, indicating another possible source for plume signature variations. Exhaust particle D32 was 1.2-1.6 /* (with a <2, 8, 28 /* trimodal distribution), independent of pressure, nozzle inlet contour, exit Mach number, degree of underexpansion, or location aft of the exit plane. The existence of a small number of larger particles indicated that either particle collision and/or surface effects occurred in the nozzle convergence, or that the larger particles at the nozzle entrance were concentrated near the wall, out of the viewing volume in the center of the flow.
Comparison of Calcium Sensitivities of αs1-B, β-A2, and γ-A2 Caseins and Their Stabilization by K-Casein A

Abstract Increasing concentrations of calcium increased precipitation of α s1 -B, β -A 2 , and γ -A 2 caseins. However, differences occurred at various concentrations of added calcium. At low calcium ( γ -casein A 2 was more calcium-sensitive than either α s1 -B or β -A 2 casein. At high added calcium (15mM), only 55% of the γ -casein A 2 precipitated compared to 94 and 80% of the α s1 -B and β -A 2 caseins. Variations in calcium sensitivity were attributed to differences in average hydrophobicity and in phosphorus content of the three caseins. Solubilities of α s1 -B, β -A 2 , and γ -A 2 caseins in the presence of 10mM calcium increased with increasing concentrations of κ -casein A. In each case, the maximum solubility was near a κ -casein/calcium-sensitive casein ratio of .10. At ratios of κ -casein A/ β -casein A 2 and κ -casein A/ γ -casein A 2 of .04 and greater, the solubility curves were similar. The ability of κ -casein to stabilize β - and γ -caseins against precipitation by calcium was attributed primarily to hydrophobic interactions. Further work on γ -casein is needed.
War, terrorism and the public's health

War and terrorism, which are inseparable, cause death and disability, profound psychological damage, environmental destruction, disruption of the health infrastructure, refugee crises, and increased interpersonal, self-directed and collective violence. Weapons systems such as weapons of mass destruction and landmines have their own specific devastating effects. Preparation for war and preparedness for terrorism bring constraints on civil liberties and human rights, increase militarism, and divert resources from health care and from other needed services. War and terrorism may be best prevented through addressing their causes, which include limited resources, injustice, poverty and ethnic and religious enmity, and through strengthening the United Nations and the treaties controlling specific weapons systems, particularly weapons of mass destruction. In particular, the United States should cease its interference in the internal affairs of other nations and its advocacy of unilateral pre-emptive war.
Structural environment of nitrogen in n-doped rutile TiO 2 (110)

We employ x-ray photoelectron spectroscopy (XPS), reflection high-energy electron diffraction (RHEED) and nuclear reaction analysis (NRA) to characterize the concentration-dependent structural properties of nitrogen doping into rutile TiO2. High quality N-doped TiO2 were prepared on rutile single crystal TiO2(110) substrates using plasma-assisted molecular beam epitaxy with an electron cyclotron resonance (ECR) plasma and Ti effusive sources. Films with N dopant concentrations at or below 2 at.% exhibited predominately substitutional doping based on NRA data, whereas films with concentrations above this limit resulted in little or no substitutional N and surfaces rich in Ti3+ . The binding energy of the N 1s feature in XPS did not readily distinguish between these two extremes in N-doping, rendering features within 0.4 eV of each other and similar peak profiles. Although widely used to characterize the state of N in anion-doped TiO2 materials, we find that XPS is unsuitable for this task.
Dispersed‐phase holdup in packed, countercurrent liquid‐liquid extraction columns

This investigation is a study of the effect of flow rates and packing size and column diameter upon the holdup of a toluene dispersed phase, flowing countercurrent to a continuous water phase in packed liquid-liquid extraction columns. Six different packings were used: ¼-, ⅜-, ½-, ⅝-, ¾-, and 1-in. nonporous, unglazed-porcelain Rasching rings. Three extraction columns, 3, 4, and 6 in. I. D., were used in the experimental work. Three types of dispersed-phase holdup, free, operational, and total, have been investigated. An empirical correlation is presented for the total holdup data below the loading point. A correlation of the effect of packing size on the exponential term r and the coefficient A1 is developed for packing sizes 1/2 in. or larger when the column-diameter-to-packing-size ratio is at least 8 to 1. The term A1(VD)r in the equation accounts for at least 90% of the total holdup. The small magnitude of the residual term B1(VD) (VC8) did not permit a definite correlation of the coefficient B1 or the exponent s. Observation of the dispersed-phase holdup during column operation revealed a transitional behavior of the 3/8-in. rings as compared with that of the 1/4- and 1/2-in. or larger packing. Two, and sometimes three, regimes of flow occur in packed extraction columns. the increase in holdup with increasing continuous-phase flow rate differed for each zone. In the two zones below the loading zone the holdup was found to increase linearly with the dispersed-phase flow rate for a constant continuous-phase flow rate. A new method of randomly packing an extraction column has been found to give reproducible holdup data.
Research on Standard Errors of Equating Differences

In this paper, the standard error of equating difference (SEED) is described in terms of originally proposed kernel equating functions (von Davier, Holland & Thayer, 2004) and extended to incorporate traditional linear and equipercentile functions. These derivations expand on prior developments of SEEDs and standard errors of equating and provide additional insight about the relationships of kernel and traditional equating functions. Simulations are used to evaluate the SEEDs' accuracies.
Book Review: Botulinum Neurotoxin for Head and Neck Disorders

A Blitzer, BE Benson, J Guss . Botulinum Neurotoxin for Head and Neck Disorders. New York: Thieme, 2012. ISBN-10: 1604065850 Botulinum Neurotoxin for Head and Neck Disorders is a moderately sized text covering a very specific, clinically relevant, and contemporary topic that is applicable to physicians in many specialties, including plastic surgery, facial plastic surgery, otolaryngology/head and neck surgery (Oto-HNS), neurology, and dentistry. An initial review of the contents of the text reveal several appealing color illustrations and diagrams and a moderately large, easy-to-read font. The 19 chapters are subdivided into 4 distinct topic sections: dystonia, other motor disorders, pain syndromes, and autonomic disorders. Following the Table of Contents is a listing of 22 online videos that demonstrate the injection techniques described in the text. The foreword provides the reader with a brief history of the medical uses of botulinum toxin (BoNT) to be described in the text, including strabismus, focal dystonias such as spasmodic dysphonia and blepharospasm, migraine headache, hyperhidrosis, and wrinkle reduction. The preface describes the intended audience for the book, which includes clinicians familiar with treating a variety of disorders affecting the head and neck—plastic surgeons, otolaryngologists, neurologists, dentists, and pain specialists. After reading this book, we would agree with the intended audience and add medical students and novice practitioners to the list. This book provides a comprehensive review of the more common clinical applications of BoNT, including the treatment of focal dystonias, pain syndromes, and cosmetic applications. Included in each section are descriptions of the pathology under consideration, important differential diagnostic considerations, accepted medical and surgical therapies for each condition, the role of BoNT in ameliorating …
370 THE EFFECT OF CALCIUM CHELATION ON LYMPHOCYTE NA AND K PERMEABILITY

Ca chelation prevents the proliferative response of lymphocytes. Lymphocyte proliferation is critically dependent on membrane adaptations including a doubling of Na and K pumping. Thus calcium chelation could disrupt the membrane and prevent the compensatory increase in active transport of Na and K. We examined the leak and pump of Na and K under conditions of Ca deprivation. Lymphocytes were studied in a medium containing EGTA so as to quantitatively reduce ionized Ca, as measured by a Ca electrode. The membrane permeability to Na and K increased when Ca activity was less than 10 μM. When Ca activity reached 0.1 μM, K and Na leak reached a maximum of 3 times control values. As leak increased, active transport increased to maintain an internal Na and K close to normal values. Intracellular Na was increased from 15 to 27 mM, and K was reduced from 145 to 137 mM in the presence of 0.1 μM ionized Ca. The 3-fold increase in Na and K transport at 0.1 μM ionized Ca was shown to be the result of the 12 mM increase in Na since a 3-fold increase in Na and K transport occurred when cell Na was increased to 25 mM by other means. Replacement of Ca completely reversed the increased membrane permeability. Thus, 1) the chelation of extracellular Ca does not restrain the ability of the Na,K-pump to compensate for increased leak and 2) Ca chelation does not block lymphocyte proliferation by inhibition of Na and K transport but does produce a dramatic increase in membrane permeability.
Cigarette nicotine content as a determinant of human smoking behavior.

Measures of smoking rate and psychological effects of cigarettes with varying nicotine content were made in 15 subjects. While subjects did perceive differences in strength and quality of the experimental lettuce cigarettes as compared to their own brands, their smoking rates did not decrease differentially over the nicotine gradient. The decrement in smoking due to the experimental cigarettes persisted when subjects resumed smoking their own cigarettes. However, the smoking that did occur in the absence of both tobacco and nicotine indicates that the habit itself often exhibits functional autonomy from the physiological effects of nicotine.
Blockade of cardiac effects of isoproterenol by the stereoisomers of sotalol.

Abstract The effect of levo- and dextro -rotatory optical isomers of sotatol [4-(2-isopropylamino-1-hydroxyethy1)-methanesulfonanilide; MJ 1999] was investigated on the myocardial stimulant effect of isoproterenol in the isolated supported (blood perfused) dog heart preparation. Intracoronary injection oisoproterenol in doses ranging from 0.0062 to 3.2 μg produced an increase in heart rate, left ventricular force (CF), left ventricular systolic pressure (LVSP), myocardial oxygen consumption (MVO 2 ) and a decrease in coronary artery perfusion pressure (CAPP) in a dose-dependent manner. All these cardiac effects of isoproterenoll were competively blocked by 0.25 mg/kg levo -sotalol. Dextro -sotalol has a minimal effect in doses up to 2 mg/kg. Levo -sotalol itself slightly depressed the heart rate, CF, LVSP and MVO 3 in these experiments. However, it produced an increase in the CAPP, and a slight decrease in 88 Rb clearance by the heart. It is concluded that levo -sotalol is the active isomer for the beta-adrenoreceptor blocking activity in the heart.
Inactivation or Loss of TTP Promotes Invasion in Head and Neck Cancer via Transcript Stabilization and Secretion of MMP9, MMP2, and IL-6

Purpose: Invasion is the critical step in progression of a precancerous lesion to squamous cell carcinoma of the head and neck (HNSCC). Invasion is regulated by multiple proinflammatory mediators. Tristetraprolin (TTP) is an mRNA-degrading protein that regulates multiple proinflammatory mediators. TTP may serve as an excellent treatment target. Rap1 is a ras-like oncoprotein that induces critical signaling pathways. In this study, the role of rap1 in TTP-mediated invasion was investigated. Experimental Design: Using complementary approaches, we modulated TTP and altered expression of interleukin (IL)-6 and matrix metalloproteinase (MMP) 2/9, which were quantified by ELISA and zymogram. Invasion was evaluated in vitro using the oral-cancer-equivalent (OCE) three-dimensional model and in vivo in the chick chorioallantoic membrane (CAM). The role of rap1 and p38 were established using knockdown strategies. Results: Downregulation of TTP significantly increased invasion via secretion of MMP9/2 and IL-6. In the novel OCE and CAM invasion models of HNSCC, cells with downregulated TTP destroyed the basement membrane to invade the underlying connective tissue. Rap1 induces p38 mitogen-activated protein kinase (p38)-mediated inactivation of TTP. Inactive TTP enhances transcript stability via binding to the 3′-untranslated region (UTR). High IL-6 and MMP9 are prognostic for poor clinical outcomes in patients with HNSCC. Conclusions: Targeting the rap1-p38-TTP cascade is an attractive novel treatment strategy in HNSCC to concurrently suppress multiple mediators of invasion. Clin Cancer Res; 19(5); 1169–79. ©2012 AACR .
A coarse-grained model for the simulations of biomolecular interactions in cellular environments

The interactions of bio-molecules constitute the key steps of cellular functions. However, in vivo binding properties differ significantly from their in vitro measurements due to the heterogeneity of cellular environments. Here we introduce a coarse-grained model based on rigid-body representation to study how factors such as cellular crowding and membrane confinement affect molecular binding. The macroscopic parameters such as the equilibrium constant and the kinetic rate constant are calibrated by adjusting the microscopic coefficients used in the numerical simulations. By changing these model parameters that are experimentally approachable, we are able to study the kinetic and thermodynamic properties of molecular binding, as well as the effects caused by specific cellular environments. We investigate the volumetric effects of crowded intracellular space on bio-molecular diffusion and diffusion-limited reactions. Furthermore, the binding constants of membrane proteins are currently difficult to measure. We provide quantitative estimations about how the binding of membrane proteins deviates from soluble proteins under different degrees of membrane confinements. The simulation results provide biological insights to the functions of membrane receptors on cell surfaces. Overall, our studies establish a connection between the details of molecular interactions and the heterogeneity of cellular environments.
The 2-oxocyclobutanecarboxylic acid keto-enol system in aqueous solution: a remarkable acid-strengthening effect of the cyclobutane ring.

Flash photolysis of 2-diazocyclopentane-1,3-dione in aqueous solution produced 2-oxocyclobutylideneketene, which underwent hydration to the enol of 2-oxocyclobutanecarboxylic acid; the enol then isomerized to the keto form of this acid. Rates of the ketene and enol reactions were measured in acid, base, and buffer solutions across the acidity range [H+] = 10-1 −10-13 M, and analysis of these data, together with rates of enolization of the keto form of 2-oxocyclobutanecarboxylic acid determined by bromine scavenging, gave keto−enol equilibrium constants as well as acidity constants of the keto and enol forms. The keto−enol equilibrum constants proved to be 2 orders of magnitude less than those reported previously for the next higher homolog, 2-oxocyclopentanecarboxylic acid, reflecting the difficulty of inserting a carbon−carbon double bond into a small, strained carbocyclic ring. The acidity constant of the enol group of 2-oxocyclobutanecarboxylate ion, on the other hand, is greater, by 4 orders of magnit...
Diagnostic Model of the Three-Dimensional Circulation in the Upper Equatorial Pacific Ocean

Abstract To investigate the processes that maintain the large-scale, annual-average thermal structure of the equatorial Pacific, the three-dimensional ocean circulation for a large area is determined from a diagnostic model applied to repeated, meridional hydrographic sections along 150°W and 11O°W from 5°N to 5°S. Geostrophic balances are used to determine velocity profiles from 0 to 500 db across the boundaries of the region: zonal velocities across 150°W and 110°W at approximately 1° -lattitude intervals from 5°N to 5°S and meridional velocities across 5°N and 5°S averaged over the zonal distance between 150°W and 110°W. Poleward wind-driven flows across 5°N and 5°S based on climatological zonal wind stress are added to the geostrophic velocities in the mixed layers. To achieve overall mass conservation, the reference dynamic height field at 500 db is adjusted at four of the 21 stations by about 1 dyn cm. Horizontal nondivergence is used to determine meridional velocities between 0.75° and 5° latitudes...
Troubled Fields: Men, Emotions, and the Crisis in American Farming

Introduction. Homework1. The Invitation to Die2. The Nelsons3. Creating Oklahoma: Positioning Farm Men for Crisis4. The Good Farmer: Gender and Occupational Role Evaluation5. The American Agriculture Movement and the Call to FarmConclusion. Modernity, Emotions, and Social Change
Periodontal Defects Associated with Root Fracture

A case is reported in which a vertical root fracture resulted in periodontal defects and the subsequent loss of the tooth.
An open-access microfluidic model for lung-specific functional studies at an air-liquid interface

In an effort to improve the physiologic relevance of existing in vitro models for alveolar cells, we present a microfluidic platform which provides an air-interface in a dynamic system combining microfluidic and suspended membrane culture systems. Such a system provides the ability to manipulate multiple parameters on a single platform along with ease in cell seeding and manipulation. The current study presents a comparison of the efficacy of the hybrid system with conventional platforms using assays analyzing the maintenance of function and integrity of A549 alveolar epithelial cell monolayer cultures. The hybrid system incorporates bio-mimetic nourishment on the basal side of the epithelial cells along with an open system on the apical side of the cells exposed to air allowing for easy access for assays.
Some Characteristics of Effective Practice in Second Language Acquisition

This article focuses on the importance of practice as a necessary component in learning a second language. Second language practice is categorized according to four general approaches to teaching foreign language: the grammar-translation (G-T) approach; the audiolingual (AL) approach; the programmed instruction (P-I) approach; and the contextual approach. A distinction is made between drill and practice. A review of research findings in related fields has shown that: (1) repetition as a learning technique is not as effective as current classroom practice implies; (2) the more meaningful the material to be learned, the better the student will learn and retain it; (3) there is a need for great variety within an experiential approach to structuring the learning environment; (4) the use of printed and other visually oriented learning materials should be an integral part of any program of instruction; and (5) the conscious learning of specific grammar rules may not be as important in learning to speak a second language as many teachers believe. The article concludes with the author's interpretation of the research findings and some suggestions for implementation of these in actual classroom situations.
Physical characteristics of setting of acrylic bone cements.

An investigation was conducted to determine the general physical characteristics of self-curing acrylic resin systems in terms of their potential utilization in total hip arthroplasty. Exothermic temperature, working and setting times were monitored with thermocouples placed in acrylic masses insulated via a Teflon mold. Mechanical strengths were run in an Instron testing machine. The same trends were noted in all systems studied. As thickness or mass increased, the maximum temperature and the setting time increased. As the powder to liquid ratio increased (thereby relatively less liquid), the maximum temperature, set times and dough times decreased, while the working time was essentially unaffected. As the ambient temperature decreased, the maximum temperature decreased while the dough, working and setting times increased. The mechanical strengths of the systems cured at one atmosphere are low compared to high temperature and pressure curing. Flowability of the materials decreases quickly as final set time is approached. Although trends are similar in many self-curing acylic systems minors shifts in complex proprietary compositions can produce a wide span or working and setting times. Because the surgical team controls such parameters as the mass employed, the amount of liquid introduced, and the ambient temperature it is important that they continuously re-evaluate their handling procedures particularly if new acrylic cements would be introduced.
Changes in Material Classification of the Urinary Bladder Wall After Spinal Cord Injury

Changes in the mechanical properties of the urinary bladder wall following neurogenic disease or trauma can result in bladder dysfunction. We have recently reported changes in the biaxial mechanical properties of the bladder wall 10 days after spinal cord injury in a rat model [1]. Development of a constitutive model to characterize these changes would facilitate quantitative comparisons and provide the necessary information for organ-level computational modeling. However, before an appropriate constitutive model of the bladder wall can be formulated, its material class must be identified. In the present study, we applied a generalized method for material classification of biaxial mechanical data to our previous data on the urinary bladder wall.Copyright © 2002 by ASME
Immunologic Studies of Arylsulfatase A in Normal and Metachromatic Leukodystrophy Liver

Summary: Purified human liver arylsulfatase A on polyacrylamide gel electrophoresis at pH 4.0 is separated into two protein forms with enzymatic activity and two distinct inactive subunits. All of these components were immunologically distinguishable using different antisera preparations. In late infantile metachromatic leukodystrophy, only one of the two inactive subunits was immunologically detected, whereas in the juvenile form of metachromatic leukodystrophy, both inactive subunits were antigenically present. Speculation: Arylsulfatase A is a dimeric enzyme composed of two distinct subunits. In late infantile metachromatic leukodystrophy, the molecular defect results in the absence of one of the subunits and therefore no active dimer is formed. In contrast, in the juvenile form of the disease, the mutation does not cause the absence of either of the subunits, as they are immunologically detectable, but does cause the formation of an unstable dimer.
SURFACE CURRENT MAPPING OFF CALIFORNIA WITH RADIOMETRY AND ALTIMETRY

Surface coastal currents off California are a good example of the complex variability in space and time of currents in an ocean basin eastern boundary. Conventional oceanographic measurements are unable to resolve these relatively small scale variations but by employing both satellite imagery and satellite altimetry we are able to resolve this complex structure and its variations in space and time. Moreover using historical satellite imagery we are able to extend this study back into the past. Our emphasis will be on resolving these variations and later studies will relate these variations to various forcing functions
Endocardial irregularities of the left atrial roof as seen on coronary CT angiography

Objective To describe and characterize morphological characteristics of endocardial irregularities in the roof of the left atrium as seen on coronary CT angiography. Methods We retrospectively evaluated the left atrium in 50 consecutive coronary CT patients with multiplanar reformatting, volume rendering, and virtual endoscopy. Results Twenty-one of the 50 patients had an endocardial irregularity at the roof of the left atrium. The most common finding (n = 14) was a smooth diverticulum, arising near the venoatrial junction of the right superior pulmonary vein. Conclusion Endocardial irregularities of the left atrium can be identified on coronary CT and may be more common than previously considered. The findings probably represent remnants of the cardinal venous system during embryological development. Further work should focus on the true prevalence and potential clinical significance.
Approximate methods of structural analysis and design in a knowledge-based system environment

Abstract A knowledge-based system (KBS) is developed for assistance at the preliminary stage of multistorey office building design. The system generates overall building configurations and then compatible structural system alternatives. The process of structural configuration is followed by an approximate design solution for structural sizing. The approach used in the implementation of approximate methods of structural analysis in a KBS environment is also illustrated by an example.
An introduction to case-based reasoning

Case-based reasoning means using old experiences to understand and solve new problems. In case-based reasoning, a reasoner remembers a previous situation similar to the current one and uses that to solve the new problem. Case- based reasoning can mean adapting old solutions to meet new demands; using old cases to explain new situations; using old cases to critique new solutions; or reasoning from precedents to interpret a new situation (much like lawyers do) or create an equitable solution to a new problem (much like labor mediators do). This paper discusses the processes involved in case-based reasoning and the tasks for which case-based reasoning is useful.
Enhancing Organizational Performance

Total quality management (TQM), reengineering, the workplace of the twenty-first century--the 1990s have brought a sense of urgency to organizations to change or face stagnation and decline, according to Enhancing Organizational Performance. Organizations are adopting popular management techniques, some scientific, some faddish, often without introducing them properly or adequately measuring the outcome. Enhancing Organizational Performance reviews the most popular current approaches to organizational change--total quality management, reengineering, and downsizing--in terms of how they affect organizations and people, how performance improvements can be measured, and what questions remain to be answered by researchers. The committee explores how theory, doctrine, accepted wisdom, and personal experience have all served as sources for organization design. Alternative organization structures such as teams, specialist networks, associations, and virtual organizations are examined. Enhancing Organizational Performance looks at the influence of the organization's norms, values, and beliefs--its culture--on people and their performance, identifying cultural "levers" available to organization leaders. And what is leadership? The committee sorts through a wealth of research to identify behaviors and skills related to leadership effectiveness. The volume examines techniques for developing these skills and suggests new competencies that will become required with globalization and other trends. Mergers, networks, alliances, coalitions--organizations are increasingly turning to new intra- and inter-organizational structures. Enhancing Organizational Performance discusses how organizations cooperate to maximize outcomes. The committee explores the changing missions of the U.S. Army as a case study that has relevance to any organization. Noting that a musical greeting card contains more computing power than existed in the entire world before 1950, the committee addresses the impact of new technologies on performance. With examples, insights, and practical criteria, Enhancing Organizational Performance clarifies the nature of organizations and the prospects for performance improvement. This book will be important to corporate leaders, executives, and managers; faculty and students in organizational performance and the social sciences; business journalists; researchers; and interested individuals.
An efficient RNA isolation procedure and identification of reference genes for normalization of gene expression in blueberry

Application of transcriptomics approaches can greatly enhance our understanding of blueberry physiology. The success of transcriptomics approaches is dependent on the extraction of high-quality RNA which is complicated by the abundance of polyphenolics and polysaccharides in blueberry. Additionally, transcriptomics requires the accurate quantification of transcript abundance. Quantitative real-time polymerase chain reaction (qRT-PCR) is a robust method to determine transcript abundance. Normalization of gene expression using stably expressed reference genes is essential in qRT-PCR. An evaluation of the stability of expression of reference genes has not yet been reported in blueberry. The objectives of this study were to develop an effective procedure for extracting RNA from different organs and to evaluate potential reference genes for qRT-PCR analyses in blueberry. RNA of high quality and yield was extracted from eight and six organs of rabbiteye and southern highbush blueberry, respectively, using a modified cetyltrimethyl ammonium bromide-based method. The expression stability of 12 reference genes was evaluated. UBIQUITIN-CONJUGATING ENZYME (UBC28), RNA HELICASE-LIKE (RH8), CLATHRIN ADAPTER COMPLEXES MEDIUM SUBUNIT FAMILY PROTEIN (CACSa), and POLYUBIQUITIN (UBQ3b) were the most stably expressed genes across multiple organs in both blueberry species. Further, the expression stability of the reference genes in the branch abscission zone following treatment with fruit abscission-inducing compounds was analyzed. CACSa, RH8, and UBC28 were the most stably expressed genes in the abscission zone under abscission-inducing conditions. We suggest a preliminary evaluation of UBC28, CACSa, RH8, and UBQ3b to identify the most suitable reference genes for the experimental conditions under consideration in blueberry.
Effect of relative humidity on lipid oxidation in freezedried emulsions

Oxidative stability was studied in a freeze-dried emulsion consisting of linoleic acid (LA), Tween-20, sucrose and maltodextrin in the presence of a catalyst (FeSO 4 /ascorbic acid). Changes in residual LA and conjugated dienes as a function of time were monitored at 0, 32, 43 and 75% relative humidities (RH). Based on GC analyses, LA oxidation was more significant in the surface fraction than the entrapped. The loss of surface oil upon storage may also be due to partial entrapment. However faster oxidation of the surface oil was confirmed by measurement of diene conjugation. Oxidation was more rapid at the lower relative humidities (0 and 32% RH) and decreased with increasing RH. At high moisture, physical modifications in the sample were observed, including reduced porosity, structural collapse, reduction of the surface oil and coalescence of oil droplets triggered by sucrose crystallization. These may be responsible for the decreased oxidation. Sucrose crystallization at the higher humidities inhibited oxidation. In addition, while samples with similar glass transition temperature (Tg) range behaved differently, samples with different glass transition range showed similar oxidative behaviour. Microstructural changes leading to oil entrapment and oil droplet coalescence were found to be significant, in this case.
Calcium entry blockers for systemic hypertension.

Abstract Calcium entry blockers appear to be effective antihypertensive agents in both young and older patients. Studies comparing diltiazem and placebo, diltiazem and propranolol, and diltiazem and hydrochlorothiazide indicate that this calcium entry blocker is more effective than placebo, equally effective as the β-adrenergic inhibitors at least in short-term studies, but not as effective in lowering systolic blood pressure (BP) when compared with hydrochlorothiazide (diastolic BP —11.5 mm Hg with diltiazem vs —12.2 mm Hg with hydrochlorothiazide; systolic BP —12.2 mm Hg with diltiazem vs —20.0 mm Hg with hydrochlorothiazide). Combination therapy with diltiazem and hydrochlorothiazide proved effective in a high percentage of monotherapy nonresponders. The most common adverse reactions to diltiazem included headaches, dizziness and edema. The exact place of calcium entry blockers in therapy as initial or step-2 therapy with a diuretic in hypertension must be determined by additional long-term experience in large numbers of patients.