cssi/SciSciGPT-SciSciNet huggingface dataset:
Las reformas de las pensiones en América Latina y la posición de los organismos internacionales

En este articulo se analiza la posicion de varios organismos internacionales y regionales en relacion con las reformas del sistema de pensiones en America Latina. En los ultimos diez anos estos han conducido estudios de casi todos los paises de America Latina (pero de pocos en el Caribe no latino), han identificado y analizado aspectos claves, comparado las reformas realizadas, han evaluado sus ventajas y desventajas, y han desarrollado estrategias o taxonomias a nivel mundial sobre el tipo de reformas ideales. El autor identifica una serie de disyuntivas o temas centrales en el debate de la segundad social. desarrolla una tipologia de las reformas al sistema de pensiones realizadas en la region y describe un modelo pretendidamente universal, analizando su viabilidad. Senala que la mayoria de los paises latinoamericanos tienen factores institucionales diversos a los de Chile (en cuya experiencia se basa esc modelo), lo que hace dificil su reproduccion integral. A continuacion sintetiza y compara las estrategias propuestas por la Organizacion Internacional del Trabajo y el Banco Mundial, en cuyo marco analiza las reformas latinoamericanas. Despues de resumir las acciones emprendidas por la Asociacion Internacional de Seguridad Social y el Banco Interamericano de Desarrollo en relacion a estos temas, analiza la propuesta de la cepal. El articulo concluye que. asi como las estrategias rigidas y generales son de dificil aplicabilidad, es tambien necesario evitar los disenos ad hoc que ignoren las ensenanzas que ha dejado la experiencia. Convendria desarrollar una tipologia por grupos de paises que tengan caracteristicas comunes —institucionales y de seguridad social—y, sobre esa base, elaborar un modelo de reforma general para cada grupo.
Reaction Rates and Selectivity in Catalyst Pores

Publisher Summary This chapter focuses on the reaction rates and selectivity in catalyst pores; and discusses the physical picture of the pore structure, the mechanism of transport in catalyst pores, and physical factors determining reaction rates on porous catalysts. Small pores appear to have fundamentally different catalytic properties, due to the peculiar way in which transport into and out of the catalyst pellet affects the reactivity of the catalyst, through its control of the partial pressure of reactant in the inner pore recesses. A catalyst pore is essentially a microscopic flow reactor. As molecules flow into a pore (mainly by diffusion), reaction occurs due to collisions with the pore wall and the partial pressure of reactant decreases, just as in a bulk scale flow reactor. Thus, the partial pressure of a reactant is in general smaller in the inner recesses of a catalyst pellet than at the pellet surface, just as the partial pressure of a reactant is lower at the outlet end of a bulk reactor than it is at the inlet end. From this simple phenomenon a large number of interesting deductions are possible.
Genetic test reporting enhances understanding of risk information and acceptance of prevention recommendations compared to family history-based counseling alone

It is unknown whether or why genetic test reporting confers benefits in the understanding and management of cancer risk beyond what patients learn from counseling based on family history. A prospective nonexperimental control group study compared participants from melanoma-prone families who underwent CDKN2A/p16 (p16) genetic testing (27 carriers, 38 noncarriers) to participants from equivalently melanoma-prone families known not to carry a deleterious p16 mutation (31 no-test controls). All participants received equivalent counseling concerning elevated lifetime melanoma risk and corresponding recommendations for prevention and screening. Both immediately and 1 month after counseling, participants receiving a genetic test result reported greater understanding of their risk, decreased derogation of the risk information, and greater personal applicability of prevention recommendations than no-test controls. Decreased derogation of risk information after test reporting predicted further increases in understanding of melanoma risk and applicability of prevention recommendations 1 month later. Results suggest unique benefits of genetic test reporting in promoting understanding and acceptance of information about hereditary cancer risk and its management.
Foreign language production and avoidance in US university Spanish-language education

Uno de los componentes principales de la gran mayoria de los cursos de lengua extranjera (LE) ofrecidos en las universidades estadounidenses es un enfoque explicito en la gramatica de la lengua, y muchos de estos cursos ensenan un gran numero de conceptos gramaticales durante el progreso del semestre universitario. Sin embargo, puede ser que los estudiantes de la LE no esten utilizando toda esta gramatica nueva para cumplir con las metas comunicativas centrales de las tareas de sus cursos de espanol. Para investigar esta cuestion, se recolectaron muestras de habla y de escritura de 32 estudiantes universitarios que estudiaban el espanol en cada uno de los cuatro niveles de instruccion universitaria. Estas muestras se analizaron en terminos de uso de gramatica, de exactitud, y de complejidad. Los resultados indicaron que estos estudiantes estan utilizando muy pocos de los conceptos gramaticales presentados en sus cursos universitarios de lengua espanola. Although the communicative language teaching (CLT) approach continues to enjoy the status of dominant orthodoxy in second language teaching, CLT is not without its drawbacks. As learners are encouraged to communicate in the target language despite a lack of necessary linguistic resources, they engage in a large amount of linguistic avoidance in order to meet their communicative goals. In order to describe how grammar is being employed in US university course assignments, speaking and writing samples were collected from 32 US university students studying Spanish at all four major levels of instruction. Samples were analyzed in terms of grammar usage and accuracy. Results indicate that these learners are using almost none of the more difficult grammatical structures presented to them in their Spanish-language university courses.
Analysis of reverse-phase protein microarrays: A comparison of trends in protein expression derived from computerized linear regression, logistic regression, and dose interpolation models

4461 Oncoproteomic characterization of the tumor microenvironment using reverse-phase protein microarrays represents a powerful platform to study alterations in signaling pathways and post-translational modifications both in response to therapeutic regimens and in relation to clinical course. The absence of standardization among proteomic techniques has contributed to difficulty in reproducing proteomic endpoints between groups. There is debate regarding the optimal computational handling of proteomics data. Newly emergent logistic modeling algorithms designed to interpret relative protein expression by image quantitation are being tested. These approaches should be compared to peer-reviewed procedures involving dose interpolation and linear regression. This will advance clinically meaningful oncoproteomic applications. Lysates derived from cell culture and human biopsy specimens were robotically arrayed on nitrocellulose slides in duplicate six-point dilution curves and subsequently stained with validated antibodies. Trends in protein expression values generated from computerized linear regression, logistic regression, and dose interpolation models were compared. Inter-rater reliability, intra-rater reliability, and coefficient of variation among intra-run duplicates were assessed within each computational method. A preliminary examination of trends in protein expression among biologic samples suggests poor correlation between linear regression and logistic regression analyses. Adequate intra- and inter-rater reliability were demonstrated. Comparisons with dose interpolation methods are ongoing. These initial results highlight the importance of properly and carefully applying the appropriate computational methods to proteomic data sets to preserve the integrity of resultant conclusions.
Surface-enhanced Raman spectroscopy of N-methylpyridinium cation and pyridine

Abstract In this paper are described the results of a series of experiments undertaken to clarify the role of the anion in surface-enhanced Raman scattering (SERS) measurements involving the N -methylpyridinium cation (NMP + ) and to identify the actual surface species observed in such experiments. We have studied the effects of varying the anion, pH and electrochemical potential, have performed competition experiments in which both pyridine and NMP + were present in the electrolyte and have compared the ordinary Raman spectrum of the solid silver-pyridine complex, Ag(py) 2 NO 3 , with the various SER spectra obtained. By these experiments, we have demonstrated that different pyridine/NMP + species are responsible for the observed spectra. In addition, it appears that surface-induced and/or photochemical reactions may produce species not originally present in the sample solution. Consequently, care must be exercised in the assignment of SER bands to sample components without consideration of possible decomposition to other species capable of producing SERS.
How Do The Small, Successful Companies In America Choose Their Auditors?

The competition among audit firms is becoming increasingly intense. The pressure to keep clients and gain new clients keeps managing partners on edge. New business is the lifeblood of an audit firm. Furthermore, the publicity surrounding giant companies like Enron, Tyco, WorldCom. et.al., and associated accounting practices has precipitated extra scrutiny of audit firms who present their audit proposals to companies for their business.
Wolves at the Door: Musical persuasion in a 2004 Bush-Cheney advertisement

Many journalists and scholars overlook the discursive role of music in TV political advertisements. But we argue that music is a potent means of political persuasion. Music in advertisements is determinative; all other elements—images, voiceovers, sound effects, written text, and so on—are circumscribed by the music and interpreted in relation to it. Music determines an advertisement’s character through framing and underscoring; musical frames establish interpretative categories and generate expectations, while underscoring comprises music that closely coordinates with images and voiceovers to form a persuasive aesthetic and rhetorical unity. A close reading of a 2004 Bush-Cheney advertisement applies this theory of frames and underscoring to explain the advertisement’s effectiveness. Without music, the advertisement would not only fail to persuade, it would also make no sense.
Do Organizational Cultures Replicate National Cultures? Isomorphism, Rejection and Reciprocal Opposition in the Corporate Values of Three Countries

Despite the intuitive relation between national and organizational culture, empirical research relating the two phenomena is sparse. This article compares the national and organizational cultures of India, Brazil, and the USA, uncovering a significant but complex relationship. Clusters are found in all three countries that both systematically replicate and reject national values. Possible reasons for these `isomorphic' and `rejective' responses to national culture are explored and their theoretical implications developed.
The effect of chloroplast coupling factor removal on thylakoid membrane ion permeability

Removal of coupling factor protein (CF1) from spinach thylakoid membranes results in an enhancement of proton permeability but has no effect on chloride or potassium permeability. Anion permeability was measured by the rate of thylakoid packed volume changes. Potassium permeability was monitored by turbidity changes, packed thylakoid volume changes and ion flux studies using 86Rb+ as a tracer. 45Ca2+ was used to measure divalent cation fluxes. CF1-depleted chloroplasts had an unaltered rate of Ca2+ uptake, but the rate of Ca2+ efflux appeared to be increased. Calcium efflux rates could also be increased by the addition of a proton specific uncoupler, FCCP.
Nonoperative treatment of adult acquired flat foot with the Arizona brace

Nonoperative treatment of posterior tibial tendon dysfunction can be successful with the Arizona AFO brace, particularly when treatment is initiated in the early stages of the disease. This mandates that the orthopedist has a high index of suspicion when evaluating patients to make an accurate diagnosis. Although there is a role for surgical management of acquired flat feet, a well-fitted, custom-molded leather and polypropylene orthosis can be effective at relieving symptoms and either obviating or delaying any surgical intervention. In today's climate of patient satisfaction directed health care, a less invasive treatment modality that relieves pain may prove to be more valuable than similar pain relief that is obtained after surgery. Questions regarding the long-term results of bracing remain unanswered. Future studies are needed to determine if disease progression and arthrosis occur despite symptomatic relief with a brace. Furthermore, age- and disease stage-matched control groups who are randomized to undergo surgery or bracing are necessary to compare these different treatment modalities. At this time, the Arizona AFO brace can be a useful weapon in the orthopedist's armamentarium for treating acquired flat foot deformity.
Preparation and characterization of SnS2

Abstract Single crystals of SnS 2 , crystallizing with the hexagonal CdI 2 structure, were grown by vapor transport and chemical vapor transport. Electronic, optical, and infrared properties were studied, as well as thermal stability in flowing oxygen. The impact on the electrical properties of slight deviations from stoichiometry and halogen impurity were investigated. Crystals free of halogen impurity can be grown by vapor transport. The sign of the majority carriers of crystals grown by vapor transport is dependent upon the growth conditions. If higher growth temperatures are used (750-700°C), vapor-grown crystals are n -type semiconductors and exhibit low resistivities (ϱ = 4.5(5) Ω cm at 25°C). Annealing of vapor-grown crystals in sulfur at 600°C increases the resistivity to 2 × 10 5 Ω cm. When the charge-growth temperatures are lowered to 650-600°C and 5% excess sulfur is included in the charge, the crystals are p -type semiconductors with high resistivities (ϱ > 10 7 Ω cm). Crystals grown in the presence of halogen (Cl 2 ) contain 22(6) ppm chlorine and are n -type semiconductors, ϱ = 5 Ω cm at 25°C. The resistivity is not altered by annealing in sulfur. The chlorine impurity acts as donor states in this material.
Agreement without Peace? International Mediation and Time Inconsistency Problems

Mediation has competing short- and long-term effects. In the short run, the actors are better able to identify and settle on a mutually satisfying outcome. In the long run, mediation can create artificial incentives that, as the mediator's influence wanes and the combatants' demands change, leave the actors with an agreement less durable than one that would have been achieved without mediation. This article tests the observable implications from this logic using a set of international crises from 1918 to 2001. The results reconcile findings in the previous literature that inconsistently portray the effectiveness of mediation.
Threat-Sensitive Behavioral Responses to Concentrations of Water-Borne Cues from Predation

Aquatic organisms often detect predators via water-borne chemical cues, and respond by showing reduced activity. Prey responses may be correlated with the concentration of predation cues, which would result in graded antipredator behavioral responses that adjust potentially costly behavioral changes to levels that are commensurate with the risk of predation. Larvae of the predatory mosquito Toxorhynchites rutilus prey upon other container-dwelling insects, including larvae of the mosquito Ochlerotatus triseriatus. Previous work has established that O. triseriatus reduce movement, foraging, and time below the surface, and increase the frequency of resting at the surface, in the presence of water-borne cues from predation by T. rutilus. We tested whether these responses by O. triseriatus are threat sensitive by recording behavior of fourth instar larvae in two runs of an experiment in which we created a series of concentrations (100, 10, 1, 0.1, and 0.01% and 100, 70, 40, 20, and 10%) of water that had held either O. triseriatus larvae alone (control) or a T. rutilus larva feeding on O. triseriatus (predation). We also tested whether associated effects on time spent feeding are threat sensitive by determining whether frequencies of filtering or browsing are also related to concentration of cues. The frequencies of resting and surface declined, whereas frequency of filtering (but not browsing) increased more rapidly with a decrease in concentration of predation cues compared with control cues. Thus, O. triseriatus shows a threat sensitive behavioral response to water-borne cues from this predator, adjusting its degree of behavioral response to the apparent risk of predation.
Suburbia: An International Perspective on Levels of Satisfaction with the Physical Environment

This cross-national study examines women's satisfaction with various aspects of the suburban environment in metropolitan regions representative of three industrialized societies. the United States (San Jose area); Israel (Tel Aviv and the Jerusalem regions), and the Netherlands (The Hague and environs). The influence of suburban environmental factors such as neighborhood location, age, and design, on four sets of dependent quality of life variables (satisfaction with housing environment, community services, social patterns, and psychological well- being), are re-examined. A questionnaire was used to collect data in 1977-78 and statistical techniques such as t-tests and partial correlation analyses were employed to examine relationships between independent and dependent variables
Transient coastal currents and inertio-gravity waves

Abstract Solutions are found for the flow field generated near a coast by the sudden application of an alongshore wind stress. Alongshore geostrophy is not assumed, and so the near-inertial oscillations are retained. The model is alongshore independent, hydrostatic, continuously stratified, has a well-mixed surface layer, and admits vertical diffusion in the anterior. The asymptotic form of the solution for large time and fixed position shows that the inertial oscillations decay like t −1/2 , leaving behind an accelerating coastally trapped baroclinic jet and a steady upwelling circulation. Calculations for up to 5 days show coastal inhibition of the inertial oscillations within the Rossby radius, outside which they increase in large parts of the ocean interior. The increase is due in part to the downward leakage of coastal inertial energy from the mixed layer and in part to the offshore leakage near the bottom. Several weeks may be needed to obtain significant decay everywhere in the flow field. Estimates of certain properties of the inertial oscillations in the model are in fair agreement with observations.
The Controversy on Group Requirements for the Degree in Liberal Arts

During the last few years there has been a growing tendency on the part of the students to play a major role in the administration of colleges and universities. Such an interest, if it represented the majority of the student body, would be a definite indication of maturity. The fact of the matter, however, is that the majority of the students, and the best students in particular, accept the organization, curriculum, and aims of the institutions where they study or remain more or less indifferent to them. The leaders of the student-faculty councils and the members of groups which attract most of the attention are generally students who do not excel in academic subjects, such as languages, mathematics, and sciences. These students want to curtail and even eliminate the group requirements of the Liberal Arts. A very considerable number of the faculty either supports these demands or is willing, through apathy, to surrender to them. The present trend to undermine a liberal education is taking place with the connivance of weak and self-seeking faculty. Since this movement has gained considerable momentum on more than one campus, it is a matter of vital interest to all of us which calls for united action. I shall, therefore, comment on the significance of not one but all the Liberal Arts group requirements. Much of the problem related to requirements rests on a clear understanding of what a liberal arts education constitutes and what the aims of a liberal arts college are. No matter how dynamic our concept of such an education may be, we cannot make it so flexible that it becomes a contradiction of its essential nature.
Triclosan-Induced Modification of Unsaturated Fatty Acid Metabolism and Growth in Pseudomonas aeruginosa PAO1

Triclosan is a broad-spectrum antimicrobial agent having low toxicity which facilitates its incorporation into numerous personal and health care products. Although triclosan acts against a wide range of gram-positive and gram-negative bacteria by affecting fatty acid biosynthesis, it is ineffective against the opportunistic pathogen Pseudomonas aeruginosa. Wild-type strain P. aeruginosa PAO1 was used as a model system to determine the effects of triclosan on fatty acid metabolism in resistant microorganisms. This was accomplished by cultivating P. aeruginosa PAO1 cultures in the presence of different concentrations of triclosan, monitoring growth rates turbidimetrically, and harvesting in stationary phase. Readily extractable lipids (RELs) were obtained from freeze-dried cells after washing and analyzed using gas chromatography coupled with mass spectrometry. Resultant data demonstrated that triclosan caused dose-dependent increases in the amounts of trans-C(16:1) and trans-C(18:1) fatty acids, with concomitant decreases in their respective cyclopropyl analogs. Triclosan did not affect the relative concentrations of saturated, cis unsaturated, or the overall ratios of combined C(16) to C(18) fatty acid species. The readily extractable lipid fractions contained triclosan proportional to triclosan concentrations in the growth media. The presence or absence of triclosan in either liquid or solid media did not affect the antimicrobial susceptibilities of P. aeruginosa PAO1 to a battery of unrelated antimicrobials. Triclosan decreased growth rate in a dose-dependent manner at soluble concentrations. Incorporation of triclosan into the REL fraction was accompanied by increased levels of trans unsaturated fatty acids, decreased levels of cyclopropyl fatty acids, and decrease in growth rate. These alterations may contribute to triclosan resistance in P. aeruginosa PAO1.
Expression and activity of collagenases in the digital laminae of horses with carbohydrate overload-induced acute laminitis.

Background Matrix metalloproteinases (MMP) are hypothesized to degrade structurally important components of the laminar extracellular matrix (ECM) in horses with laminitis. Objective To compare levels of expression of stromelysin-1 (MMP-3), collagenases (MMP-1, -13), and membrane type-MMPs (MMP-14, -15, -16), and the distribution of their ECM substrates, in laminae of healthy horses and horses with carbohydrate overload laminitis. Animals Twenty-five adult horses. Methods Gene and protein expression were determined in extracts of laminae using real-time quantitative polymerase chain reaction and Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis. Distribution of MMP-13 and ECM components was determined using indirect immunofluorescent microscopy of nonfixed frozen sections. ECM morphology was assessed by hematoxylin and eosin staining. Results Of the genes studied, only those encoding MMP-1 and -13 were upregulated in CHO-induced laminitis; MMP-1 at Obel grade (OG)1 lameness and MMP-13 at OG3 lameness. Laminar MMP-1 was present as 52 kDa proenzyme only. MMP-13 was present as pro- (61 kDa) and processed (48 kDa) enzyme. MMP-13 localized to the basal epithelium of the secondary epidermal laminae and its increased expression were accompanied by the appearance in secondary dermal laminae (SDL) of multiple foci that were devoid of collagen I, fibronectin, chondroitin and keratan sulfate glycosaminoglycans, and eosin-staining material. Conclusions and Clinical Relevance MMP-13 is upregulated in laminae of horses with CHO-induced OG3 lameness and, by degrading components of the ECM, may contribute to the formation of ECM-free lesions (gaps or tears) that appear in the SDL with OG3 lameness.
Extremely metal-poor gas at a redshift of 7

In typical astrophysical environments, the abundance of heavy elements ranges from 0.001 to 2 times the solar value. Lower abundances have been seen in selected stars in the Milky Way’s halo and in two quasar absorption systems at redshift z = 3 (ref. 4). These are widely interpreted as relics from the early Universe, when all gas possessed a primordial chemistry. Before now there have been no direct abundance measurements from the first billion years after the Big Bang, when the earliest stars began synthesizing elements. Here we report observations of hydrogen and heavy-element absorption in a spectrum of a quasar at z = 7.04, when the Universe was just 772 million years old (5.6 per cent of its present age). We detect a large column of neutral hydrogen but no corresponding metals (defined as elements heavier than helium), limiting the chemical abundance to less than 1/10,000 times the solar level if the gas is in a gravitationally bound proto-galaxy, or to less than 1/1,000 times the solar value if it is diffuse and unbound. If the absorption is truly intergalactic, it would imply that the Universe was neither ionized by starlight nor chemically enriched in this neighbourhood at z ≈ 7. If it is gravitationally bound, the inferred abundance is too low to promote efficient cooling, and the system would be a viable site to form the predicted but as yet unobserved massive population III stars.
Thermally Processed Keratin Films

Keratin obtained from poultry feathers was modified with glycerol, which acted as a plasticizer. Films were prepared by pressing the modified keratin at temper- atures concurrent with typical polymer processing temper- atures. The films were completely cohesive as opposed to partially cohesive if pressed under the same conditions without glycerol. The films were "tough" and the mechan- ical properties show similarities to the properties of com- mercially available commodity thermoplastics. The keratin films were produced in a few minutes without reducing or oxidizing agents. The keratin films could have potential applications for which environmentally friendly materials are needed, such as food packaging or mulching films. © 2005 Wiley Periodicals, Inc.* J Appl Polym Sci 97: 1644 -1651, 2005
A remote control process for the routine synthesis of branched chain [1-11C]α amino acids

Abstract We describe the implementation of a modified Bucherer-Strecker synthesis for the facile production of several natural branched-chain, [ 11 C]carboxy-labelled amino acids and of a carbocyclic analogue. The amino acids obtained by this process include the following: dl -Val, dl -Leu, dl -Ileu and α-amino-isobutyric and 1-amino-cyclopentane-1-carboxylic acids. A remote control apparatus specifically constructed for the routine, safe application of this process is also described. This apparatus allows the sequential batch-production of two amino acids, either the same of different, in average radiochemical yields between 1.48 and 2.59 GBq (40 and 70 mCi) and with average specific activities of 92.5 GBq (2.5 Ci)/mmol.
Nonlinear properties of hollow-core photonic band-gap fibers

Our measurements and modeling of two hollow-core photonic band-gap fibers show that glass contribution to the effective non-linearity strongly depends on the fiber structure. We investigate wavelength dependence of total fiber nonlinearity.
Inhibition of lysyl oxidase and prolyl hydroxylase activity in glucorcorticoid treated rats

Abstract Triamcinolone diacetate produced a dose dependent decrease in lysyl oxidase activity in the skin of new born rats when administered over a three day period. Maximum inhibition by this glucorticoid resulted in less than 10% of control lysyl oxidase activity. A similar though less dramatic effect was observed on skin prolyl hydroxylase activity. These results suggest that the antianabolic effect of glucocorticoids on collagen synthesis extend to enzymes involved in the intra- and extracellular modifications of collagen.
Water absorption in thermally grown oxides on SiC and Si: Bulk oxide and interface properties

We combine nuclear reaction analysis and electrical measurements to study the effect of water exposure (D2O) on the n-type 4H-SiC carbon face (000 1¯) MOS system and to compare to standard silicon based structures. We find that: (1) The bulk of the oxides on Si and SiC behave essentially the same with respect to deuterium accumulation; (2) there is a significant difference in accumulation of deuterium at the semiconductor/dielectric interface, the SiC C-face structure absorbs an order of magnitude more D than pure Si; (3) standard interface passivation schemes such as NO annealing greatly reduce the interfacial D accumulation; and (4) the effective interfacial charge after D2O exposure is proportional to the total D amount at the interface.
Presynaptic Inhibition in Primate Lateral Geniculate Nucleus

SINCE their discovery1–4, the effects of midbrain stimulation on excitability of the visual system have been studied extensively. Work on the squirrel monkey5,6 has shown that the centrencephalic system exerts a powerful control over transmission through the lateral geniculate nucleus (LGN) for both photically and electrically elicited responses. Initial experiments showed facilitation following electrical stimulation of the mesencephalic reticular formation or natural alerting stimuli. Recent experiments, however, have shown that a brief period of inhibition precedes the facilitation and, as set forth below, strongly suggest that this inhibition is presynaptic in nature.
Whole wafer critical point drying of MEMS devices

Stiction induced by capillary forces during the post-release drying step of MEMS fabrication can substantially limit the functional yield of complex devices. Supercritical CO2 drying provides a method to remove liquid from the device surface without creating a liquid/vapor interface, thereby mitigating stiction. We show that a continuous stirred-tank reactor (CSTR) model can be applied as a method to estimate the volume of liquid CO2 required to effectively displace the post release solvent. The CSTR model predicts that about 8 volume exchanges is sufficient to effectively displace the methanol to a concentration below the saturation point. Experimental data indicate that about 10 exchanges are adequate for repeatable drying of complex devices, which is in reasonable agreement to the model prediction. In addition to drying devices without inducing stiction, the process must be inherently non-contaminating. Data indicate that the majority of contaminants deposited during the drying process can be attributed to contaminants originating in the post-release solvent, rather than the supercritical CO2 process.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A pilot study of 2-octyl cyanoacrylate injection for treatment of gastric fundal varices in humans.

Abstract Background N-butyl cyanoacrylate injection has been shown to be effective and safe for the endoscopic treatment of gastric varices. N-butyl cyanoacrylate is not available in the United States, but use of a similar agent, 2-octyl cyanoacrylate, recently was approved for skin closure. This pilot study prospectively evaluated the efficacy and safety of 2-octyl cyanoacrylate injection for treatment of gastric fundal varices. Methods Twenty-five patients with large gastric fundal varices with either stigmata of recent hemorrhage, a history of bleeding, or high-risk varices underwent intravariceal injection of undiluted 2-octyl cyanoacrylate. The end points for this study were cessation of active bleeding, successful obliteration of visible varices, and prevention of bleeding. Results Within 2 weeks of treatment, 52% of patients had a history of significant variceal bleeding, and 12% had active gastric variceal bleeding at the time of injection. The rate of immediate hemostasis was 100%. Gastric variceal bleeding recurred in 4% of patients (mean follow-up 11 months). The overall mortality rate was 12%; the bleeding-related mortality rate was 4%. Conclusions Injection of 2-octyl cyanoacrylate appears to be efficacious and safe for both prevention and control of gastric variceal hemorrhage. Larger studies are required to further establish the use of 2-octyl cyanoacrylate for treatment of gastric fundal varices.
10.6 continuous-time linear equalization with programmable active-peaking transistor arrays in a 14nm FinFET 2mW/Gb/s 16Gb/s 2-Tap speculative DFE receiver

We report the implementation of a continuous-time linear equalizer (CTLE) featuring a new technique to control the high-frequency gain peaking and to interface to current-summing stages usually implemented as interleaved slices for the linear analog superposition of the coefficients of decision-feedback equalizers (DFE). The circuits are implemented in 14nm FinFET SOI CMOS technology and are included ina prototype receiver targeted to 16Gb/s serial I/O links for multi-core microprocessors off-chip communication. The architecture is shown in Fig. 10.6.1. Power efficiency and compactness are among the primary goals of the study together with an equalization capability sufficient to recover at bit-error rate (BER) levels below 10−12 data transmitted across smooth channels with losses in excess of 25dB at 8GHz.
Low-pressure carbon dioxide enhanced polymer chain mobility below the bulk glass transition temperature

The effects of low-pressure carbon dioxide (CO2) on chain mobility of polystyrene (PS) and poly(methyl methacrylate) (PMMA) thin films coated on a solid surface were studied using PS/deuterated PS/Si and PMMA/deuterated PMMA/SiO2 configurations. The time evolution of chain diffusion below the bulk glass transition temperature (Tg) with and without CO2 was measured by neutron reflectivity. It was found that polymer chains at the interface can self-diffuse at a temperature below their bulk Tg because of higher surface chain mobility and that adding CO2, even at low pressures, can greatly enhance the chain mobility. When the interactions between the polymer chains and the substrate are weak as in the PS/Si configuration, the confining effects of the substrate are not significant, while in the case of the PMMA/SiO2 configuration the interactions are strong enough to confine polymer chains onto the substrate at the nanoscale. Introducing CO2 tends to alleviate this confining effect.
Physical and chemical indicators of urban visual air quality judgments

Abstract Key issues in the selection of physical/chemical measures of atmospheric properties as indicators of judgments of visual air quality are addressed. The relations between measures and judgments made over a variety of times, observation locations and atmospheric conditions are examined experimentally. Light scattering measured throughout the day at a site characterized by high aerosol concentrations was the single measure most strongly related to judgments of visual air quality. A combination of measures taken at a single site and/or other sites are somewhat better indicators of visual air quality than light scattering alone. Light extinction measured by a telephotometer is strongly related to midday visual air quality. The 4-h averaged fine particle sulfur and 12-h averaged fine particle S, sulfate, nitrate and ammonium are all strongly related to the corresponding mean visual air quality. Although these midday hourly and 4-h and 12-h average measures may be used to indicate trends in visual air quality, hourly measures taken throughout the day are required for monitoring diurnal patterns or worst case visual air quality. The application of the method and findings to understanding visual air quality in other urban areas is discussed.
Factorial Invariance Within Longitudinal Structural Equation Models: Measuring the Same Construct Across Time

Charting change in behavior as a function of age and investigating longitudinal relations among constructs are primary goals of developmental research. Traditionally, researchers rely on a single measure (e.g., scale score) for a given construct for each person at each occasion of measurement, assuming that measure reflects the same construct at each occasion. With multiple indicators of a latent construct at each time of measurement, the researcher can evaluate whether factorial invariance holds. If factorial invariance constraints are satisfied, latent variable scores at each time of measurement are on the same metric and stronger conclusions are warranted. In this paper we discuss factorial invariance in longitudinal studies, contrasting analytic approaches and highlighting strengths of the multiple-indicator approach to modeling developmental processes.
Strategic issues for charities and philanthropies

Abstract This article explores the need for charities and philanthropic bodies to develop strategies which emphasize efficiency and service and the examples and evidence presented highlight some important issues for fundraisers. The most obvious implication is the need for charitable bodies to institute environmental scanning and strategic planning.
WT1 represses HOX gene expression in the regulation of gynaecologic tumour histologic type

Homeobox genes encode transcription factors that dictate developmental identity, including that of the Mullerian tract. These genes also direct differential Mullerian transformation of the ovarian cancer cells. The homeobox gene HOXA10 controls uterine organogenesis during embryonic development and similarly is expressed in endometroid epithelial ovarian cancer. Here we confirmed aberrant regulation of HOXA10 expression in epithelial uterine and ovarian carcinomas. We identified a HOXA10 epithelial regulatory element containing an enhancer that drove HOXA10 expression specifically in gynaecologic epithelium. We further identified an adjoining dominant repressor element that restricted regulation by the epithelial enhancer to a subset of epithelial cell types. The repressor contained two functional WT1 binding sites. We identified a strong inverse correlation between HOXA10 expression and that of the Wilms’ Tumour 1 (WT1) gene in multiple benign and malignant gynaecologic tissues, suggesting functionality of the WT1 sites in the repressor. Mutation of the two WT1 binding sites abolished WT1 binding to the element as well as the ability to affect epithelial enhancer activity in reporter assays. Similarly, decreased expression of WT1 using siRNA prevented repressor activity. The Mullerian phenotype seen in ovarian cancer is dependent on gain of HOX gene expression secondary to the loss of WT1-mediated HOX repression. This suggests that Gynaecologic epithelial histologic type is regulated by WT1 expression through its selective repression of HOX genes.
A Cognitive Approach to Meaningful Mathematics Instruction: Testing a Local Theory Using Decimal Numbers

A theory is proposed for how students develop competence with the written symbols of decimal fractions. The theory views competence as the cumulative and sequential mastery of four separate cognitive processes in working with written symbols. The first two processes develop for the user the semantics of the symbol system, and the second two elaborate its syntax. Initial predictions from the theory were tested by instructing small groups of students for about 2 weeks. As predicted, (a) most students were able to acquire the first two processes, (b) these processes generated correct performance and transferred to novel tasks, and (c) it was more difficult for students to acquire the semantic-based processes once they had routinized syntactic processes. The theory and data are interpreted in the context of some persistent issues in mathematics learning.
Mechanisms of formation and decomposition of hypervalent chromium metabolites in the glutathione-chromium(VI) reaction

Abstract A long-lived chromium(IV) intermediate is generated during the reaction between Cr(VI) and glutathione in glycine below pH 3. The intermediate reacts with the tripeptide to produce Cr(III) and oxidized glutathione. A dynamic magnetic susceptibility measurement based on a nuclear magnetic resonance method yielded a 2.8 μ B magnetic movement for the chromium(IV) species. The intermediate is formed by parallel third-order and second-order processes. The third-order process ( k = 5.9 × 10 2 M −2 s −1 ) involves first-order participation by each of the oxidant, reductant, and hydrogen ions. A hydrogen ion independent pathway leads to a sluggish second-order process ( k = 0.11 M −` s −1 ) that is first order with respect to reduced glutathione [GSH] and [Cr(VI)]. Chromium(IV) species is reduced to Cr(III) by a second-order process ( k = 0.13 M −1 s −1 ) that is first order in each of [Cr(IV)] and [GSH] and does not depend on [H + ]. At pH 3.4, a chromium(V) species was detected as a minor intermediate as well. In the pH range 6.5–7.5, three dominant chromium(V) intermediates were detected. The existence of Cr(IV) in low pH offers an opportunity to examine the mechanism of DNA damage by this rare oxidation state.
How meritocratic is the United States

Abstract This paper argues that a meritocracy exists to the extent that economically valued positions are allocated on the basis of educational attainment and performance, cognitive ability, and general personal dispositions like conscientiousness. The paper justifies these components of merit on the grounds that each is notably linked to job performance or is a reasonable predictor of performance. Drawing on the status attainment and wage determination literatures, this review establishes that in absolute terms the meritocratic impact is significant though not decisive, but the meritocratic impact is much more consequential than the impact of ascribed characteristics.
Optical Design Methods for Spectrographic Systems

Hamiltonian methods are applied to spectrometer design using linearly spaced gratings. The aberration function is expanded in terms of system construction parameters, constraints are then derived on certain parameters which ensure some low-order image properties.
Applying Multigroup Confirmatory Factor Models for Continuous Outcomes to Likert Scale Data Complicates Meaningful Group Comparisons

Treating Likert rating scale data as continuous outcomes in confirmatory factor analysis violates the assumption of multivariate normality. Given certain requirements pertaining to the number of categories, skewness, size of the factor loadings, and so forth, it seems nevertheless possible to recover true parameter values if the data stem from a single homogeneous population. It is shown that, in a multigroup context, an analysis of Likert data under the assumption of multivariate normality may distort the factor structure differently across groups. In that case, investigations of measurement invariance (MI), which are necessary for meaningful group comparisons, are problematic. Analyzing subscale scores computed from Likert items does not seem to solve the problem.
The Role of Laser Vascular Targeting and Retinoic Acid in Oral Cancer Inhibition

Objectives/Hypothesis The study examines the role of the pulsed-dye laser at 585 nm, coupled with retinoic acid at therapeutic dose of 5.0 mg/kg body weight, in inhibiting chemically induced tumor growth in the hamster cheek pouch to determine whether pulsed-dye laser therapy can inhibit tumor growth and whether a combination of pulsed-dye laser and retinoic acid has a synergic effect on treatment efficacy. Study Design Randomized, prospective study of hamster model. Methods Forty-eight male golden Syrian hamsters were painted with 0.5% solution of 9,10-dimethyl-1,2-benzanthracene in acetone for 6 weeks to induce dysplasia in both sides of the cheek pouches. The hamsters were then randomly divided into four groups of 12 hamsters each as follows: (1) control group, (2) pulsed-dye laser treatment only (8.0 J/cm2 and two pulses), (3) retinoic acid treatment only (5.0 mg/kg/d by intraperitoneal injection), and (4) combined pulsed-dye laser and retinoic acid treatment. The treatment period was 40 days. Tumors were measured throughout the study. Results The results indicated that retinoic acid and pulsed-dye laser each significantly delay tumor growth and reduce tumor volume when used alone. Tumor volumes were statistically different among the treatment groups. There was also a statistical difference in tumor volume between the retinoic acid treatment group and the combined pulsed-dye laser and retinoic acid treatment group. Conclusions The study demonstrated the greater advantage of combining pulsed-dye laser with retinoic acid over using either retinoic acid or pulsed-dye laser alone for delay of oral cancer progression. Clinical trials are warranted to establish efficacy in humans.
Botulinum toxin treatment of facial myoclonus in suspected Rasmussen encephalitis

Patients with Rasmussen encephalitis (RE) may develop a variety of involuntary movements. We report a 26-year-old woman who presented with a 3-year history of progressive, continuous myoclonus of the left side of the face and left arm as well as left spastic hemiparesis. Magnetic resonance imaging of the brain showed right hemisphere and basal ganglia atrophy, and 24-hour electroencephalogram demonstrated diffuse slowing with random sharp waves in both hemispheres. An 18-fluoro-deoxy-glucose positron emission tomography scan indicated hypometabolism of the right cerebral hemisphere, including basal ganglia and thalamus. We successfully treated her myoclonus with injections of botulinum toxin A into the left zygomaticus muscle.
A RESEARCH NOTE EVALUATION OF RESTRUCTURED LOW-FAT HAM CONTAINING WHEY

Restructured, low-fat boneless ham was formulated with 0 (control samples), 20, and 30% liquid whey to replace water in the cure formulation. Sensory characteristics, visual traits, objective color, tenderness measurements, weight and cooking loss, proximate analysis, and microbial load were determined to compare this product with that from a conventional cure formulation. No differences (P>0.05) in traits (except percentage moisture) were found among samples with 0, 20, and 30% liquid whey in the formulated hams. A lower (P 0.05) from those with 0 and 30%. These results suggest that up to 30% liquid whey may be incorporated in a cured, low-fat ham formulation with similar results to products cured with a conventional formulation.
Hydroxyproline in Chlorella and its Metabolism in Tobacco Leaves

Hydroxyproline and other compounds were labeled with C14 by Chlorella pyrenoidosa supplied with C14O2 in the light. The hydroxyproline recovered from a hydrolysate of the algae was administered through the cut bases of tobacco leaves. The leaves formed little proline from the hydroxyproline, but the C14 label was transferred to a variety of other amino acids. Although hydroxyproline is not abundant in plants, it appears to be an active metabolite.