cssi/SciSciGPT-SciSciNet huggingface dataset:
Chapter 6 Demand for education

Publisher Summary The human capital “revolution” of the 1960s and 1970s turned the previously peripheral topic of demand for education into a major area of research for labor economists. Analysis has focused on a variety of questions relating to the role of education in an economy, individual decision-making with respect to demand for education, and social provision of education. The chapter examines the theoretical and empirical findings from the past two decades of work on these related issues. The chapter discusses the considerable progress made along the paths developed in the late 1950s and early 1960s, as discussed by several economic analysis of demand for education. It is the proposition that economic analysis of rational behavior under specified market and informational conditions goes a long way to understanding the interplay between education and the economy. The evidence on which this conclusion is based, and the specific findings on the social, individual, market, and public finance questions of concern, are presented in the chapter. One of the fundamental issues that motivate economic analysis of education is the extent to which education contributes to national output and, in the context of economic growth, the extent to which increased educational attainment contributes to long-run increases in productivity. One of the key elements of the human capital model of demand for education is that education affects earnings.
Adaptive control with nonlinear reference systems

Although reference systems with linear dynamics are common in the adaptive control literature, they can lead to limitations on the achievable closed-loop dynamical system performance. This is due to the fact that linear reference systems can only approximate the desired closed-loop behavior of nonlinear dynamical systems in narrow regions of the state-space. In this paper, we study a new adaptive control architecture for uncertain dynamical systems based on a nonlinear reference system. It is shown that the system error between the uncertain dynamical system and the nonlinear reference system asymptotically vanishes in steady-state, and its performance is guaranteed during the transient-time. Two illustrative numerical examples are provided to demonstrate the efficacy of the proposed methodology.
Using Greedy Hamiltonian Call paths to detect stack smashing attacks

The ICAT statistics over the past few years have shown at least one out of every five CVE and CVE candidate vulnerabilities have been due to buffer overflows. This constitutes a significant portion of today’s computer related security concerns. In this paper we introduce a novel method for detecting stack smashing and buffer overflow attacks. Our runtime method extracts return addresses from the program call stack and uses these return addresses to extract their corresponding invoked addresses from memory. We demonstrate how these return and invoked addresses can be represented as a directed weighted graph and used in the detection of stack smashing attacks. We introduce the concept of a Greedy Hamiltonian Call Path and show how the lack of such a path can be used to detect stack-smashing attacks.
Creation and characterization of temperature-sensitive mutants of the lck tyrosine protein kinase.

Abstract Temperature-sensitive mutants of the lck tyrosine protein kinase were created by the introduction of mutations known to cause temperature sensitivity of the v-src tyrosine protein kinase of Rous sarcoma virus. p56lck activated by mutation of the regulatory site of tyrosine phosphorylation, Tyr-505, to Phe transforms fibroblasts in culture. Mutations identical to those responsible for the temperature-sensitive phenotypes of the tsNY68 and tsNY72-4 v-src mutants rendered this activated lck gene temperature sensitive for both morphological transformation and induction of growth in soft agar. The mutant proteins were incapable of cellular transformation at the nonpermissive temperature in part because of failure of the lck protein to accumulate to normal levels. Morphological transformation of fibroblasts was detectable within 24 h of a shift of cells to the permissive temperature and was essentially complete in 48 to 72 h. These mutants should prove useful for the study of the function of the lck kinase in hematopoietic cells.
Translating Nutrition Research into Action in Humanitarian Emergencies

Except for the management of severe malnutrition, there has been little research specifically conducted to support emergency food and nutrition programs. Lacking empirically based guidance regarding how accurately to identify problems and select the most effective means to achieve desired objectives, programming decisions have been based on extrapolations, anecdotal evidence and intuition, with hopes of doing the right thing. Consequently, donors, implementers and affected governments, who often hold contradictory opinions, expend time and resources on controversies about when and how to act. These controversies reveal inadequate knowledge for which research is urgently needed. Two past controversies are presented as illustrations: one related to ration energy requirements and the other to sales of food aid. Appropriate action depends on context and research to support emergency programming must encompass a broad range of sectors and disciplines. Furthermore, emergency contexts are characterized by extremes and dynamic change and investigations in such contexts demand special approaches and caution. Institutional structures need to be changed so that they can adequately support emergency nutrition research.
Abstract 308: Corticosteroid Therapy Benefits Septic Mice With Adrenal Insufficiency but Harms Septic Mice Without Adrenal Insufficiency

Rationale: Corticosteroid (CS) therapy is frequently used in septic patients. However, the efficacy of CS therapy is highly controversial. The heterogeneity of septic patients, the technical difficulties in identifying adrenal insufficiency and a lack of adrenal insufficiency animal model present significant barriers to address this longstanding clinical issue. Objectives: In this study, we utilized scavenger receptor BI (SR-BI) null mice as the first relative adrenal insufficiency animal model to evaluate the efficacy of CS therapy and assess the pathogenesis caused by adrenal insufficiency. Methods: Cecal ligation and puncture (CLP) was conducted on SR-BI-/- and wild type control mice, and then CS was administered 2 or 18h post CLP. Measurements and Main Results: We demonstrated that CS supplementation protects against CLP-induced sepsis in SR-BI-/- mice but causes more septic death in wild type controls. Importantly, we identified a cocktail of CS that provides more efficient protection than an individual CS, and the septic mice could be rescued 18h post CLP by the CS cocktail; we further demonstrated that adrenal insufficiency impairs both innate and adaptive immunity. Conclusions: This preclinical study provides a proof-of-concept that corticosteroid benefits septic patients with adrenal insufficiency but harms septic patients without adrenal insufficiency, and suggests that it is necessary to determine the status of adrenal insufficiency and only prescribe corticosteroid for septic patients with adrenal insufficiency.
Telemedicine: news from the front lines.

identiﬁed telemedicine as a potentially “disruptive innova-tion” that could change medical practice. The rollout ofteleradiology, a branch of telemedicine, provides a relevantcase study.Along the lines described by Christensen et al, earlyteleradiology clients were small rural hospitals lacking on-site radiologists and not averse to receiving less than“Cadillac”-level services. The initial teleradiology serviceproviders were academic radiology departments that couldconveniently expand their nighttime service workforce byrecruiting their own cash-strapped senior radiology residentsand fellows seamlessly into their own nighttime serviceoperations. Once such teleradiology services were on astrong ﬁnancial footing, venture capitalists gladly fundedstart-up companies to fully commercialize teleradiologyservices. Today, teleradiology services are available at alarge percentage of all US hospitals and are regarded bymany as mainstream medical services.
Ionization of Na Rydberg Atoms by Subpicosecond Quarter-Cycle Circularly Polarized Pulses

We report the first observation of ionization of Rydberg atoms by subpicosecond, circularly polarized THz radiation. The field amplitude in these pulses is non-negligible for only one-quarter of an optical cycle. The experiment is performed in the short-pulse regime, where the duration of the ionizing pulse is shorter than the classical Kepler period of the Rydberg electron. We find that the ionization probability for these atoms is remarkably insensitive to the time-varying polarization of the THz field.
The cast aluminum denture base. Part I: Rationale

Experiments with various casting techniques have been done, and aluminum base dentures have been made for many patients. The subjective clinical response from patients wearing aluminum dentures has not been different from patients wearing acrylic resin dentures. However, Brudvik and Holt have stated that they have had marked clinical success in using aluminum bases. A literature review on using aluminum as a denture base material has been presented, and the rationale for its use has been discussed. In part II, a technique will be described that can be used for casting aluminum denture bases.
Employment status and the attitudes and behavior of higher status women volunteers, 1975 and 1992: A case study

This study examines the relationships between employment status and women's attitudes toward and participation in a higher status voluntary service organization. Data were gathered in 1975 and 1992 from a sample of chapters of the International Association of Women (a pseudonym). The 1992 sample included three percent who reported a racial or ethnic identification other than white. Drawing on several theoretical perspectives, we expected to find differences in the attitudes and level of participation of employed versus non-employed members that would have important effects on organizational functioning. However, few differences in the attitudes of members employed full time, part time, and not in the labor force were found in either 1975 or 1992. There were, however, differences in behavior. Employed members reported spending much less time on organizational activities and were less likely to assume leadership roles, but these differences diminished between 1975 and 1992 as employed women became numerically dominant in the organization, suggesting that the growing presence of employed women in IAW led to the development of informal norms and new policies about the amount of time members should devote to the organization and a corresponding loss in the total number of volunteer hours devoted to it.
Discussion: Social Science and Related Implications

What we are discussing is a U.S. public policy document. Its message reinforces and is complemented by the rising concerns of nonfarm groups. The right to food is discussed as a component of the human rights package. The World Food Council, some think, may become a serious forum for north-south dialogue. There is hope that Public Law 480 may become a food for development program with decreased emphasis on surplus disposal and diplomatic leverage. More importantly, international interdependencies among nations and societies are increasingly understood. Thus, a variety of forces is at work to place at least part of the World Food and Nutrition Study's (WFNS's) recommendations on the national policy agenda. In an effort to improve the performance of development aid, donors are demanding more sophisticated and rigorously prepared projects and programs. The capacity of many less developed countries (LDC's) to meet these standards is still limited. As a result, there has developed an increasing flow of development aid searching for suitable programs and projects. Equation of demand and supply cannot rely in the long term on transitory expatriate expertise. Rather, domestic LDC capacity to meet this need and tap into the global community of science, technology, and governance must increase. Much of what the WFNS recommends is intended to speed this process. But the new aid resources coming on stream will have to show at least some results rather soon if desired momentum is to be sustained. Against this background, I have four observations. First, as agricultural economists we may well be challenged to provide more than we are prepared to deliver. Scientific and technological advances of biophysical and engineering types, while exciting, critically important, and likely to be forthcoming, are in themselves insufficient to the task. Nontechnological constraints may well be the critical ones. Involved are proper public policies in the rich as well as in the poor countries and development of the institutions, programs, and projects they foster. Biophysical scientists frequently speak with conviction when they say: "We have the technological package right. All that is holding it back is wrongheaded price, trade, tax, land tenure, exchange rate, or investment policies." Often economists are the first to agree. We also know, however, that much technology has been unsuccessfully promoted because it was not well tailored to the agroclimatic and socioeconomic circumstances of the intended
Synthesis and structure of trans-[di(μ-acetato)dichlorodi-(μ-bis(diphenylphosphino)methylamine)dimolybdenum(II)] and the structure of bis(diphenylphosphino)methylamine

Abstract Trans-[Mo2(μ-O2CCH3)2Cl2(μ-dppma)2] (2) can be synthesized from Mo2(μ-O2CCH3)4 (1), trimethylchlorosilane and bis(diphenylphosphino)methylamine (dppma) (3) at room temperature. In contrast to the related compounds containing dppa (bis(diphenylphosphino)amine) this molecule displays significant torsion angles in both the acetato and the diphosphine ligands and significantly shorter MoCl bond distances. These differences are also reflected in the spectroscopic data. Crystallographic data for 2 are as follows: I2 ( No. 5), a = 13.056(3), b = 14.814(4), c = 14.954(4) A , β = 100.76(1)°, V = 2841(1) A 3 , Z = 2.d( MoMo ) = 2.172(1) A . For comparison with compound 2 the free ligand, dppma (3), was also examined by X-ray crystallography. Crystallographic data are as follows: Pna21 (No. 33), a = 13.5061(2), b = 14.3943(2), c = 11.231(3) A , V = 2183.5(5) A 3 , Z = 4 .
Neoplasms of mixed mesenchymal and neuroepithelial type With consideration of the relationship between meningioma and neurilemmoma

Abstract Four cases are described of intracranial neoplasms of mixed mesenchymal and neuroepithelial (glial) type. The multipotential mesenchyme differentiated into meningioma, neurilemmoma and rhabdomyosarcoma in various combinations, but meningioma was common to all 4 instances. The neuroepithelial part was astrocytoma in 3 cases and glioblastoma in 1, but ependymoma was mingled in 1 instance, and oligodendroglioma in another. A unitary diagnosis had been made previously in each case, usually by ignoring the gliomatous component. Meningocytes, fibroblasts and Schwannian cells are categorized as mesenchymal; meningioma and neurilemmoma are interpreted as related mesenchymal neoplasms having some histologic differences. These tumors may arise directly from mesenchymal cells. This concept resolves the controversy about their cell of origin, explains their occurrence in various locations within as well as outside the neuraxis, and provides an explanation for the presence of aberrant tissues such as striated muscle in the central nervous system.
Hydrogeochemical Exploration for Barite, Ouachita Mountains, U.S.A.

ABSTRACT Steele, K.F. and Wagner, G.H., 1983. Hydrogeochemical exploration for barite, Ouachita Mountains, U.S.A. In: G.R. Parslow (Editor). Geochemical Exploration 1982. J. Geochem. Explor., 19: 243–254. Approximately 100 springs were sampled as part of a general geochemical survey in a 130 by 140 km multi-mineralized area of the Ouachita Mountains. The study area was subdivided into Area I and Area II based on differences in lithology and mineralization. Area I is composed primarily of the Paleozoic Stanley Shale and the Arkansas Novaculite Formation, and has considerable manganese (often present as psilomelane) and barite mineralization. The barite occurs primarily as replacement deposits in shale in Area I. Area II is composed of Paleozoic and Cretaceous sedimentary rocks, and Quaternary alluvium. Mercury, antimony, strontium and barite mineralization is present. The barite mineralization occurs as cement in the Cretaceous sandstone and gravel in this area. The widely prevalent barite cement in Area II is reflected by higher median and upper range values of barium concentration and also higher median and threshold % BaSO4 saturation values. The presence of barite as cement in the sediments of Area II tends to mask the detection of the barite deposits in this area. Approximately 83% of the sites within 1.7 km of known barite mineralization in Area I were characterized by anomalous barium concentration, and 67% within 3.4 km. Anomalous % BaSO4 saturation values and Ba/Sr ratios produced success rates generally similar to those of anomalous barium concentrations. Anomalous strontium concentrations did not prove effective in detecting barite mineralization.
Industrial concentration of ethnic minority- and women-owned businesses: evidence from the survey of business owners in the United States

Abstract Using a confidential national survey of ethnic minority- and women-owned businesses in the United States and multivariate regression analyses, this study examines how businesses are concentrated in different industrial sectors across ethnicity and gender, and how the segmentation by the divide of ethnicity and gender is associated with business performance. The findings indicate that male- and female- owned businesses have distinctive industrial concentration patterns. In particular, compared to white women, businesses owned by women from ethnic minority groups are highly concentrated in a limited number of industrial sectors. Concentration in specific industrial sectors does not necessarily mean poor performance when measured by sales, size of employment or payrolls. However, for women-owned businesses, those sectors obviously pay less and have marginal profits, especially if considering the size of the firms.
Sheltering homeless families: beyond an emergency response.

Economic misfortune and the seuerity of the housing crisis do not entirely account for homelessness among families. To respond to their complex social welfare and mental health needs, the long-term policy response must include a range of superuised, supported, and independent (with supports) housing options.
Solution properties of a CO2-soluble fluoropolymer via small angle neutron scattering

In this communication, we report the first characterization of solutions of a high molecular weight polymer in supercritical CO{sub 2} by small-angle neutron scattering (SANS). It is shown that small-angle neutron scattering gives key molecular parameters of an amorphous fluoropolymer in supercritical CO{sub 2}, i.e., the molecular weight, radius of gyration, and second virial coefficient, and thereby gives insights into a polymer chain`s behavior in this unique solvent. The positive sign of the second virial coefficients indicate that this medium is a good solvent - there is no evidence of a collapsed chain conformation. In fact, we conclude from the SANS data that, in CO{sub 2}, the poly(FOA) chain dimensions are expanded relative to those characteristic of its melt. 29 refs., 2 figs., 1 tab.
Changing Directions in One Language Methods Class.

Every future foreign language teacher faces at least one language methods class. This class is usually a bland mixture of the history and philosophy of teaching languages. My experience teaching Education 450F-Methods of Teaching a Foreign Language-has allowed me to create a more innovative and practical course for the future language instructor. The content of the fifteen week course falls into three interrelated areas: (1) exposing students to language activities and related programs currently operating in public schools and colleges; (2) engaging students in a microteaching program in which they prepare materials and present them before high school students; and (3) providing discussion sessions which consist of (a) the instructor and microteachers receiving feedback on teaching projects, and (b) the instructor and class collectively exploring theory and techniques utilized in the microteaching projects.
Melatonin rhythms in the eyes, pineal bodies, and blood of Japanese quail (Coturnix coturnix japonica).

Abstract Melatonin levels in the eyes, pineal bodies, and blood of Japanese quail exposed to 12L:12D show robust daily rhythms with high levels occurring in the night and low levels occurring during the day. Since melatonin is synthesized in both the eyes and pineal bodies of birds, the relative contribution of these structures to the blood melatonin levels was determined. A rhythm of blood melatonin persisted in 12L:12D in birds blinded by complete orbital enucleation and in pinealectomized birds but the nighttime levels were reduced by 33 and 54%, respectively, as compared to melatonin levels in control quail. Only a small melatonin rhythm (13% of control levels) was detected in the blood of pinealectomized, blinded quail. This “residual” rhythm could indicate either the contribution of extrapineal, extraocular sources of melatonin or melatonin secretion from remnants (if any) of pineal body tissue remaining after pinealectomy. Blinding did not obviously affect pineal melatonin levels nor did pinealectomy affect ocular melatonin levels. It was concluded that (1) daily rhythms in melatonin content occur in the pineal bodies, the eyes, and the blood of quail; (2) the blood rhythm is the result of melatonin secretion from both the pineal body and the eyes; (3) extraretinal photoreceptors can mediate entrainment of the pineal melatonin rhythm; and (4) obvious compensatory changes in melatonin levels do not occur in the eye following pinealectomy or in the pineal body following blinding.
Summer phytoplankton blooms in the oligotrophic North Pacific Subtropical Gyre: Historical perspective and recent observations

Abstract The export of organic matter from the oceanic euphotic zone is a critical process in the global biogeochemical cycling of bioelements (C, N, P, Si). Much of this export occurs in the form of sinking particles, which rain down into the unlit waters of the deep sea. Classical models of oceanic production and export balance this gravitational loss of particulate bioelements with an upward flux of dissolved nutrients, and they describe reasonably well those areas of the ocean where deep winter mixing occurs. The surface waters of the North Pacific Subtropical Gyre (NPSG), however, are strongly stratified and chronically nutrient-depleted, especially in summer. Nevertheless, there is ample evidence that blooms of phytoplankton and subsequent pulses of particle export occur during the height of summer stratification in these waters, especially to the northeast of the Hawaiian Islands. These blooms impact regional bioelemental cycling and act as a food source to the deep-sea benthos. We review here numerous published observations of these events in the NPSG, and present new data collected at Station ALOHA (22.75°N, 158°W) during the first 176 cruises of the Hawaii Ocean Time-series program (1988–2005), along with results from transect cruises conducted in the region in 1996 and 2005. We suggest that the summer phytoplankton bloom can be considered a frequent, perhaps annual feature in the northeastern NPSG, and that its perceived stochastic nature is a manifestation of chronic undersampling in time and space. The bloom is typically dominated by only a few genera of large diatoms and the cyanobacterium Trichodesmium. It appears to be consistently supported by dinitrogen fixation, but the fate of the organic matter produced during the summer depends critically on the species composition of the responsible diazotrophs. We estimate that the summer bloom is responsible for up to 38% of N2 fixation and up to 18% of N-based new production annually at Station ALOHA. We hypothesize that the spatial distribution, timing and magnitude of the bloom may be determined largely by the physical and biological processes controlling new phosphorus delivery into the euphotic zone during the summer and the preceding winter.
Trypsin inihibitors inhibit induction by interferon-γ of HLA-DR antigen expression on human skin cells

Abstract Serine protease inhibitors with a specificity for trypsin inhibit interferon-γ (INF-γ)-induced HLA-DR expression on a hybrid human epidermal cell line (H12), dermal fibroblasts, and primary keratinocytes. Protease inhibitors with a specificity for chymotrypsin or papain fail to inhibit IFN-γ. The inhibitory effect of the trypsin inhibitors is similar to that of glucocorticoids in that it is a transient event, fading with length of exposure to IFN-γ, and is reversed by the addition of dibutyryl cyclic AMP (dbcAMP) and phospholipase C(PLC) from Clostridium perfringens . In H12 cells, dbcAMP and PLC enhance the IFN-γ induction of HLA-DR, but do not induce in the absence of INF-γ. Evidence suggests that the protease inhibitors, as well as dbcAMP and PLC, may modulate HLA-DR expression at a post-translational site as well as during IFN-γ signal transduction. These results suggest that trypsin-like protease activity may be required for cellular HLA-DR antigen expression following exposure to IFN-γ.
Utilization of Alfalfa Hay and Alfalfa Silage. 2. Protein Sources in Ensiled Corn Stover Diets

Two hundred ninety-one steers were randomly allotted to four diet treatments in which corn silage or ensiled corn stover was fed as an energy source and alfalfa hay or alfalfa silage was fed as a protein source. Performance of steers fed different protein sources in corn silage diets was similar. However, for steers fed ensiled corn stover, daily gains (.28 kg) of steers fed alfalfa hay were nearly double gains (.15 kg) of steers fed alfalfa silage as the protein source. Efficiencies (.036 vs. .024 kg gain/kg feed) were also improved for steers fed alfalfa hay. Ensiled alfalfa had the greater initial (0 h) soluble nitrogen (66.2 vs. 39.3% of total nitrogen) but a much slower rate of solubilization of residual nitrogen (total nitrogen minus initial soluble nitrogen and acid detergent insoluble nitrogen) than alfalfa hay. Although total quantity of ruminally degradable protein would be greater for alfalfa silage than for alfalfa hay, the amount and rate of release of nitrogenous constituents (i.e., peptides, amino acids, and ammonia) from alfalfa silage appeared to be less favorable for microbial digestion of ensiled corn stover.
Generalized representation of handwriting: evidence of effector independence.

Abstract Previous analyses of writing data have provided qualitative evidence of temporal and spatial similarities across muscle effectors. In order to further explore the notion of effector independence in handwriting a single case study approach was adopted employed quantitative analyses. A left-handed individual who lost his left hand and forearm in an automobile accident and wore a myoelectric arm was tested. After his accident he learned to write with the right hand developing this skill 8 years. Once he was fitted with the myoelectric arm he began again to write with the left hand. Thus, the acquired writing patterns of both hands reflect two well-learned skills which utilize different muscle effectors. Wright's NAME-EQUATION paradigm (1990) was utilized which required the subject to write his name and the equation X + Y = Z with the dominant, non-dominant hand and the elbow ofthe arm. A control subject was also tested. For the subject wearing a myoelectric arm (primary subject), kinematic and handworking analysis revealed astonishing similarities between the different effectors tested. For the control subject, the obtained results showed that as the effectors changed so did the handwriting kinematics. The collective findings support the hypothesis that motor programs, the directives that guide skilled movement, can be generalized across different effectors, but only after considerable practice.
Electronic absorption and emission spectral data and fluorescence quantum yields of bridgedp-oligophenylenes, bi- to deciphenyls, and related furans and carbazoles.

Absorption and fluorescence emission spectral data, as well as fluorescence quantum yields (Φf), were determined for 41p-oligophenylene compounds containing 2–6, 8, and 10 benzene rings. Of 29 compounds containing carbon-bridged rings (fluorenes), 28 were dialkylated on each bridge for improved solubility and photostability. Absorption maxima for oligophenylenes were observed at wavelengths as long as 366 nm, emission maxima to 437 nm, and molar extinction coefficients (ɛ) as large as 153,000 L/mol-cm; all three exceeded predicted maximum values for the corresponding unbridged oligophenylenes. The substitution of furan for benzene or carbazole for a fluorene (two examples each) bathochromically shifted absorption and emission maxima. Dialkylated carbon bridges bathochromically shifted absorption and emission maxima, and lowered Φf in biphenyl and in one terphenyl analogue, but appeared to cause no diminution of Φf in higher oligophenylenes. Bis(2-methoxyethyl) substitution on the bridges, incorporated to provide solubility in polar solvents, lowered Φf in all examples. Tertiary alkyl substituents on terminal rings bathochromically shifted the absorption and emission maxima and generally increased Φf. The “loose bolt” effect, which lowers Φf in mononuclear substituted benzenes, may operate in 9,9-dialkylfluorenes, but not in 2,7-di-t-butylfluorene or in higher oligophenylenes. Cyclic ether and methoxy substituents as auxofluors on terminal rings generally bathochromically shifted absorption and emission maxima and increased ɛ and Φf. Cyano substituents bathochromically shifted absorption and emission maxima, and increased ɛ, but lowered Φf slightly.
Hydraulic fracturing of a saturated porous medium-I: General theory

Abstract This investigation deals with the problem of steady state hydraulic fracture in an infinite isotropic fluid-saturated elastic porous medium induced by a uniform pressure applied to the crack surfaces. A quasi-static approach is employed in the study. A boundary value problem is formulated and then analyzed by means of the Fourier transform associated with the Wiener-Hopf technique. Stress intensity factor and potential energy release rate are found by asymptotic analysis and the superposition principle as functions of the speed of crack propagation. The material breakdown process at the crack tip is discussed based on Dugdale's model. Finally, a brief discussion of the effect of pressure drop on the hydraulic fracture process and the decrease in crack speed during crack extension is included.
Future advances in addiction treatment

Abstract In the next decade, we should witness a number of treatment advances for opioids, stimulants, and cannabis derivatives. For opioids, this will include long acting, i.e., one month to one year, injectable or implants of the antagonist naltrexone, injectable or implants of the partial agonist buprenorphine, and innovative detoxification methods using buprenorphine. In addition, there should be much wider office based prescribing of buprenorphine for maintenance as financial, stigma, and numerical prescribing barriers are overcome. Possible new developments for cocaine dependence include vaccines that provide either active or passive immunization; agonists that could decrease craving without producing euphoria; blocking agents that do not block normal pleasures; and CRF (corticotrophin releasing factor) antagonists which could decrease both craving and relapse. In the short term, medications currently marketed for other indications that show promise for cocaine include modafinil, tiagabine, topiramate, and disulfiram. Until recently, there has been little effort toward developing medications to treat marijuana abuse/dependence. Potential medications now being considered include the agonist dronabinol, rimonabant, an antagonist and inverse agonist, and Sativex, an aerosol combining THC and cannabidiol, a non-psychoactive cannabis ingredient. Behavioral interventions will continue to be necessary, not just to increase the likelihood that patients will take effective medications but also to assist them in improving their interpersonal, educational, and vocational skills so as to develop positive rather than just negative reasons for wanting to stop drug use.
Isolation of a novel Arabidopsis ozone-induced cDNA by differential display.

We have used a reverse transcriptase polymerase chain reaction procedure (differential display) to isolate cDNAs corresponding to transcripts that accumulate in ozone-treated Arabidopsis thaliana. In this report we describe the characterization of an ozone-induced transcript, AtOZI1. AtOZI1 mRNA in untreated plants was detected at low levels in cotyledons, leaves, and flower buds and at higher levels in roots and mature flowers. AtOZI1 mRNA accumulation was transiently induced in leaves 3- to 5-fold within the first 6 h of ozone treatment. AtOZI1 mRNA accumulation was also transiently induced 3- to 6-fold by photopathogenic Pseudomonas strains. Sequence analysis of AtOZI1 revealed that it encodes a 8.6 kDa basic protein that contains a putative signal peptide and two potential phosphorylation sites. Our results suggest that AtOZI1 represents a novel stress-related protein that accumulates in response to the production of active oxygen species.
Laser Doppler phase shifting using a high-speed digital micromirror device

Abstract Here we demonstrate the use of a binary spatial light modulator (Texas Instruments Digital Micromirror Device) to impart a phase shift to the beams of a laser Doppler velocimeter. Advantages of this approach to laser Doppler phase shifting include low cost, low power consumption, a precisely known phase-stepping frequency and the capability of working with a broad range of optical wavelengths. In the implementation shown here velocities of order 1 cm/s are measured.
DEGRADATION OF CRUDE OIL ENHANCED BY COMMERCIAL MICROBIAL CULTURES

ABSTRACT Remediation and cleanup of oil spills has been attempted using different technologies. Biological methods such as bioremediation have been favored over others due to their cost efficiency and their low environmental impact. Bioremediation of Alaska North Slope crude oil was effectively attempted in a laboratory study using 13 commercial products. The products containing the microorganisms were provided by different vendors. The treatments were tested over a 28-day period, and the samples were extracted and analyzed using standard methods. After 28 days, four products showed an effective enhancement of the bioremediation process: the saturate fraction was degraded approximately 80%, and the aromatic fraction was degraded approximately 70%. Biological markers such as pristane, phytane, and C30 hopane were partially degraded.
A comparison of methods for determination of total lipids in human milk

Abstract A modified Folch extraction, a Celite-Na 2 SO 4 column elution, a spectrophotometric method and the creamatocrit method for total lipid analysis of human milk were compared against the Roese-Gottlieb method. The constant, proportional and random errors associated with each method were determined. Pooled milk was centrifuged to separate milk lipid and skim milk. Varying concentrations of milk lipid were reintroudced into the skim milk to provide 25 samples for analysis with a range of lipids from approximately 0.5 to 8.0 percent. There was a high correlation (r>0.977) between the Roese-Gottlieb method and all methods evaluated. A least squares equation was developed between the Roese-Gottlieb method and each method tested. The greatest constant error, as estimated by the least squares y-intercept, was observed with the Celite Na 2 SO 4 column procedure and spectrophotometric method. The greatest proportional error as estimated by the slope was observed with the Celite-Na 2 SO 4 column procedure. Random error based on the least squares standard error of estimate in the y direction was greatest for the spectrophotometric method. While there are differences between methods, with careful standardization all the methods tested could provide satisfactory results for analysis of total lipids in human milk.
Characterization of lipoprotein a by capillary zone electrophoresis.

Abstract Lipoprotein a [Lp(a)] has been recognized as a significant marker for premature coronary heart disease (CHD). In this paper, we present the results of Lp(a) analysis based on capillary zone electrophoresis (CZE). CZE separation of Lp(a) and its reduced species, lipoprotein a − [Lp(a − )] and apolipoprotein a [apo(a)], was accomplished using 50 m M borate buffer containing 3.5 m M sodium dodecyl sulfate (SDS) and 20% (v/v) acetonitrile (ACN). Low density lipoprotein (LDL) and high density lipoprotein (HDL) were separated under the same buffer conditions. The electrophoretic mobilities of both Lp(a) and Lp(a − ) were found to be different from that of LDL. Benzyl alcohol (BA) and methanol (MeOH) were used as electroosmotic flow markers. BA molecules associated with Lp(a − ) and LDL to enhance their UV absorbance, but did not change their effective electrophoretic mobilities. Our results show that CE is a very efficient and effective technique for lipoprotein analysis.
Variables que contribuyen a fumar tabaco entre una muestra joven: un análisis multivariable

ResumenAl estudiar la incidencia del consumo de cigarrillos entre la poblacion estudiantil (10–18 anos) y su relacion con las variables mas significativas, nos encontramos con la compleja realidad que sufre modificaciones en estas edades. De ahi que las variables significativas sufran numerosos cambios, por ej. el numero de amigos que fuman segun los diferentes grupos de edad. A los 10–11 anos, el hecho de fumar mas, se relaciona con el numero de horas de estudio en casa y con la menor estimacion de peligro que supone para la salud. A los 12–13 anos sera la propia actitud del alumno hacia el fumar, y a partir de los 14–15 anos sera tanto la actitud del grupo de amigos como la sensacion de la identidad personal. Por otro lado, se resalta el importante factor de cambio que supone pasar de E.G.B. a EE.MM.
Sasayaki: augmented voice web browsing experience

Auditory user interfaces have great Web-access potential for billions of people with visual impairments, with limited literacy, who are driving, or who are otherwise unable to use a visual interface. However a sequential speech-based representation can only convey a limited amount of information. In addition, typical auditory user interfaces lose the visual cues such as text styles and page structures, and lack effective feedback about the current focus. To address these limitations, we created Sasayaki (from whisper in Japanese), which augments the primary voice output with a secondary whisper of contextually relevant information, automatically or in response to user requests. It also offers new ways to jump to semantically meaningful locations. A prototype was implemented as a plug-in for an auditory Web browser. Our experimental results show that the Sasayaki can reduce the task completion times for finding elements in webpages and increase satisfaction and confidence.
Effects of simulated herbivory on nitrogen enzyme levels, assimilation and allocation in Thalassia testudinum

Recent estimates suggest that turtlegrass ( Thalassia testudinum) can persist while being heavily grazed by smaller herbivores (e.g., sea urchins and bucktooth parrotfish) in many areas of the western North Atlantic. Based on studies conducted in terrestrial and aquatic ecosystems, we hypothesized that seagrasses compensate for grazer-induced losses of aboveground production by (1) increasing the uptake of growth-limiting nitrogen from the surrounding environment and (2) translocating this newly acquired nitrogen to grazed tissues. We tested our hypotheses by comparing the activity levels of nitrogen metabolizing enzymes (nitrate reductase (NR) and glutamine synthetase (GS/T)) and the distance of nitrogen translocation, in the roots and leaves of mechanically damaged and undamaged plants. These experiments were repeated along a seasonal productivity gradient (in mid summer, early fall, and late fall). Significantly greater enzyme activity (GS/T) was measured in the roots of clipped plants in all months. NR and GS/T activity was also significantly higher in partially clipped leaves than in unclipped outer leaves in two of three months. The degree of leaf damage had no impact on the enzyme activity of inner (i.e., younger) leaves. Nitrogen-15, as either ammonium or nitrate, was translocated up to 50 cm away from the application point within 48 h. Defoliation, however, did not lead to increased 15 N accumulation in clipped segments, suggesting
Trends in Education Excellence Gaps: A 12-Year International Perspective via the Multilevel Model for Change.

A recent study in the USA documented the existence and growth of “excellence gaps” among students. These gaps are similar to the minimum competency achievement gaps that proliferate in policy discussions in many Western countries, but excellence gaps focus on the highest level of achievement rather than minimum competency. We extend this research using an international approach, data from the most recent Trends in International Mathematics and Science Study, and a multilevel model for change to examine excellence gap trends with specific emphasis on sex and immigrant status of the student. At an international level, sex-based findings are encouraging. Specifically, we found evidence of shrinking sex-based excellence gaps in both science and mathematics. With respect to immigrant status and excellence gaps, small gaps in the proportion of advanced achievers persist over time. In the context of large demographic changes worldwide, we argue that these findings are generally encouraging.
Weak transient signal detection in non-Gaussian noise using RBF and recurrent networks

In most of the developed transient signal detection algorithms, the background noise is usually assumed to be Gaussianly distributed to simplify the derivation of generalized likelihood ratio test (GLRT). However, in many real-world applications like target detection in ultra wideband SAR images, the distribution of dominant interference usually have long tails, and can not be characterized simply by Gaussian distribution. The performance of the linear GLRT detector, which is optimal under the Gaussian background noise assumption, would be badly degraded.In this paper, we take locally optimum approach to develop weak transient signal detection utilizing Laguerre recurrent networks for subspace projection, as well as radial basis function networks for tracking non-Gaussian noise statistics. Experiments show that the proposed weak transient signal detectors perform better than GLRT in the impulsive background noise environment.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Tongue-twister effects in the silent reading of hearing and deaf college students☆

Abstract To investigate whether deaf readers use phonological information during sentence comprehension, deaf and hearing college students performed a semantic acceptability task on tongue-twister and control sentences. Indicative of phonological coding, subjects' responses were influenced by the phonetic content of the sentences they were reading and by the phonetic content of a concurrent memory load task. That is, the subjects in both groups made more errors in their acceptability judgments when reading tongue-twister than when reading control sentences. In addition, subjects in both groups made more errors when the tongue-twister sentences and concurrent memory load numbers were phonetically similar than when they were phonetically dissimilar. These results support theories that assign phonological processes an important role in reading.
Antigen Presentation Machinery (APM) Modulation and Soluble HLA Molecules in the Tumor Microenvironment: Do They Provide Tumor Cells with Escape Mechanisms from Recognition by Cytotoxic T Lymphocytes?

The crucial role played by HLA class I antigens in the interactions of malignant cells with HLA class I antigen restricted, tumor antigen-specific cytotoxic T lymphocytes (CTL) and with NK cells ha...
Provisions for naive users of model management systems

Model management systems (MMS) have typically focused on model formulation or problem representation, and thus have often been conceived as tools for experienced model builders. In this paper, attention is drawn to the roles of naive users of MMS. Then we present a prototype MMS which was designed and developed with this rationale. MMS II, a frame-based prototype MMS, is a tool equipped with facilities for direct retrieval of models, guided retrieval, model modification and integration of models retrieved from different model bases. Discussed here are the original features designed to aid naive users, i.e. non-professional model builders. These include navigational guidance through a model base, if-sought attachments for explanation and suggestions, providing a critique via shadow processing, approximation following failure to retrieve a suitable model, suggestions of models to modify, and model integration via specification of model links.
Thermal stability and degradation of diglycidyl ether of bisphenol A epoxy modified with different nanoclays exposed to UV radiation

Abstract The primary focus of this study was to evaluate the effects of different montmorillonite nanoclays (MMT) on the thermal stability and degradation of epoxy composites exposed to UV radiation and elevated temperatures. Diglycidyl ether of bisphenol A (DGEBA) epoxy resin, SC15 was reinforced with three different montmorillonite nanoclays, Nanomer® I.28E, Cloisite® 10A and Cloisite® 30B. Thermal properties of modified DGEBA nanocomposites were characterized. Subsequently, neat and nanocomposites were subjected to 500 h of UV radiation and characterized to determine the effects of various nanoclays on the degradation. Addition of nanoclays increased the thermal properties compared to the unmodified composite and better retention of material properties after exposure to UV radiation. Viscoelastic properties increased with addition of nanoclays in both unexposed and UV radiation exposed samples.
A variational principle for large axisymmetric strain of incompressible circular plates

Abstract A generalized variational principle is established for large axisymmetric deformation of a circular plate composed of an incompressible, hyperelastic material. Independent variation of stresses, strains, displacements and boundary tractions provides the field equations and boundary conditions for arbitrarily large strain with transverse shear deformation neglected. Based on the principle of stationary potential energy, a Rayleigh-Ritz technique yields approximate solutions for clamped and hinged plates under uniform surface pressure. Coupling between bending and membrane action induces significant alterations in the stress behavior, especially near the edge of the clamped plate.
In situ evidence for the nature of the seismic layer 2/3 boundary in oceanic crust

THE igneous oceanic crust is typically thought of as comprising two layers: an upper crust ('seismic layer 2') characterized by a rapid increase in seismic velocity with depth, and a thicker lower crust ('seismic layer 3') which is distinguished from layer 2 by both a higher P-wave velocity (6.69 ± 0.26 km s -l) and a much smaller vertical velocity gradient ( 1.8 km) continuous hole drilled into the oceanic crust11–13, and find that at this location the seismic layer 2/3 boundary lies within the sheeted-dyke complex, where it is associated with gradual downhole changes in crustal porosity and alteration, not a litho-logical transition from sheeted dykes to gabbro.