cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermal Diffuse Scattering of Low-Energy Electrons

The thermal diffuse scattering of low-energy electrons is calculated in the high-temperature limit using the kinematical approximation. It is assumed that the electrons are scattered by the surface layer and that the thermal motions of the target can be approximated by the vibrations of an isotropic elastic continuum. It is found that the intensity of the scattered beam is inversely proportional to the perpendicular distance from the tip of the scattering vector to the nearest reciprocal lattice rod. It is shown that the effect of the free-surface boundary conditions is to double (approximately) the intensity without significantly changing the diffraction pattern. In the vicinity of the (00) rod, nearly half the intensity comes from the Rayleigh surface mode. Brief comparisons are made with experiment and with other theoretical treatments.
Time and Historical Consciousness: The Case of Ilparakuyo Maasai

In a manner somewhat unusual in anthropological discourse, most writers on the Maa-speaking peoples of Tanzania and Kenya include an early section or chapter on what is often called “Maasai traditional history.” For example, in his pioneering work, “An Administrative Survey of the Masai Social System,” Henry Fosbrooke (1948) devotes a leading and major section to Maasai history and, in a later publication, he deals explicitly with what he calls a “tribal chronology” of the pastoral Maasai (Fosbrooke 1956a). Similarly, Thomas Beidelman, in an equally pioneering article, pays considerable attention to the historical connections of the Ilparakuyo (Baraguyu) section of the Maasai peoples of Tanzania (1960). It is among the Ilparakuyo that I have carried out most of my work in Maasai studies, and they are the primary focus of the present discussion (Rigby 1977, 1979, 1980, 1981).
The use of pentoxifylline to improve motility of cryopreserved equine spermatozoa.

Abstract Pentoxifylline was evaluated as a method to increase motility of cryopreserved equine spermatozoa. In a preliminary experiment, pentoxifylline (3.5 mM or 7.0 mM) was added to extended semen that was chilled to 4°C. Motility was evaluated at 8-h intervals for 48 h. The addition of 3.5 or 7.0 mM pentoxifylline appeared to increase the motility of chilled spermatozoa compared to controls. Based on these results, similar concentrations of pentoxifylline were added to semen either before or after cryopreservation. The addition of pentoxifylline (3.5 or 7.0 mM) to semen before cryopreservation significantly (P
Coefficient Omega Bootstrap Confidence Intervals: Nonnormal Distributions

The performance of the normal theory bootstrap (NTB), the percentile bootstrap (PB), and the bias-corrected and accelerated (BCa) bootstrap confidence intervals (CIs) for coefficient omega was assessed through a Monte Carlo simulation under conditions not previously investigated. Of particular interests were nonnormal Likert-type and binary items. The results show a clear order in performance. The NTB CI had the best performance in that it had more consistent acceptable coverage under the simulation conditions investigated. The results suggest that the NTB CI can be used for sample sizes larger than 50. The NTB CI is still a good choice for a sample size of 50 so long as there are more than 5 items. If one does not wish to make the normality assumption about coefficient omega, then the PB CI for sample sizes of 100 or more or the BCa CI for samples sizes of 150 or more are good choices.
Systemic responses during local viral infections: Type I IFNs sound the alarm

Type I IFNs are well known for their role in controlling virus replication and spread. Type I IFNs produced by the infected tissue also signal beyond the boundaries of the infection to regulate different elements of the anti-viral immune response. Recent reports show that type I IFNs directly condition naive monocytes residing in the distal bone marrow (BM) and induce the expression of effector molecules in memory T cells, before their recruitment to the infected site. In addition, hematopoietic stem cells (HSCs) were shown to enter the cell cycle in response to systemically distributed type I IFNs. These discoveries expand our understanding of the pleiotropic effects of type I IFNs during infection and highlight the critical role of systemic signals in the development of an effective response to a localized viral infection.
Current psychoanalytic theory and practice: Can there be any one valid unitary approach?

In this brief presentation, I have discussed the historical continuum of present day psychoanalysis with its early antecedents. I have described some basic concepts which illustrate where seemingly diverse psychoanalytic methodologies, based on differing scientific philosophies, actually join up, namely, in the areas of empathy, empathic resonance, "optimal responsiveness," and in the understanding and technical work with transference. Space limitations precluded mentioning issues around theories of resistance and of cure. I finished by mentioning a few general points which distinguish self psychology's approach. While a comprehensive unitary scientific philosophy awaits the further development and maturation of an infant science, nevertheless, we can agree, I think, that there are unitary principles that govern psychoanalysis, and that organize the clinical approach of the most effective of its practitioners.
Conference chair welcome message

On behalf of the Institute of Electrical & Electronic Engineers Systems Council, may I extend a warm welcome to the 5th International Systems Conference here in the wonderful, charming and historic city of Montreal. We hope that you enjoy not only the conference with its extensive Technical Program and Exhibits, but also the charm that this beautiful area has to offer - especially during this fine Spring week!
Association of circulating active and total ghrelin concentrations with dry matter intake, growth, and carcass characteristics of finishing beef cattle.

Ghrelin is a gut peptide that when acylated is thought to stimulate appetite. Circulating ghrelin concentrations could potentially be used as a predictor of DMI in cattle. The objective of this experiment was to determine the association of circulating ghrelin concentrations with DMI and other production traits. Steers and heifers were fed a finishing diet and individual intake was recorded for 84 d. Blood samples were collected via jugular venipuncture following the DMI and ADG measurement period. Plasma active ghrelin and total ghrelin were quantified using commercial RIA. Active ghrelin was not correlated to DMI (P = 0.36), but when DMI was modeled using a multivariate analysis including plasma metabolites and sex, active ghrelin was shown to be positively associated with DMI (P 0.10). Results indicated that ghrelin concentrations are associated with DMI in beef cattle and that there is genetic variation that leads to differences in the amount and form of circulating ghrelin which could contribute to variation observed in DMI of beef cattle.
Equation of state for NaCl-H 2 O: comparison with mineral dehydration equilibria

A previously published equation of state is examined with respect to validity of predicted fugacity values for comparison with mineral reaction equilibria. It is found that values of f H2O should be valid for the range from 0.0 to 0.3 and probably to 0.4 in mole fraction NaCl for temperatures from 300° to 600° C and less accurately to 900° C. Comparison is made with existing experimental results near 630° C for the dehydration of brucite; the agreement is excellent. Comparison with recent results at 850° C from a different experiment is also satisfactory. However, fugacity of NaCl is not given on an absolute basis, even in this range below x NaCl=0.4.
A1-Type Overgroups of Elements of Order p in Semisimple Algebraic Groups and the Associated Finite Groups

Keywords: semisimple algebraic groups ; closed connected subgroups ; finite groups ; fixed point subgroups Reference CTG-ARTICLE-1995-001doi:10.1006/jabr.1995.1285 Record created on 2008-12-16, modified on 2017-05-12
Single-wall carbon nanotube forest arrays for immunoelectrochemical measurement of four protein biomarkers for prostate cancer.

Protein arrays that measure multiple protein cancer biomarkers in clinical samples hold great promise for reliable early cancer detection. Herein, we report a prototype 4-unit electrochemical immunoarray based on single-wall carbon nanotube forests for the simultaneous detection of multiple protein biomarkers for prostate cancer. Immunoarray procedures were designed to measure prostate specific antigen (PSA), prostate specific membrane antigen (PSMA), platelet factor-4 (PF-4), and interleukin-6 (IL-6) simultaneously in a single serum sample. All of these proteins are elevated in serum of patients with prostate cancer, but they have widely different relative levels of serum concentration. Horseradish peroxidase (HRP) was used as label on detection (secondary) antibodies in a sandwich immunoassay scheme. Biotinylated secondary antibodies (Ab2) that bind specifically to streptavidin−HRP conjugates provided 14−16 labels per antibody and gave the necessary higher sensitivity required for PF-4 and IL-6 detectio...
Subtalar joint instability: current clinical concepts

There has been extensive research and investigation into the subtalar joint (STJ), yet the biomechanics that relate to its anatomic function, especially instability after injury, are surrounded by controversy. With a mechanism of injury closely related to the classic inversion ankle sprain, chronic instability can result following trauma to the lateral ligamentous support network of either joint. Over the past decades there have been countless examples in the literature challenging the current standard of evaluation and treatment of the "subtalar sprain." New technologies have offered varied approaches to diagnostic capability, each with its own strengths and weaknesses, ranging from standard radiographs to CT and MRI. A review of the literature should aid in deciphering the controversy surrounding this aspect of podiatric medicine.
Actinomycin D: Renewed RNA Synthesis after Removal from Mammalian Cells

Suppressed RNA synthesis exceeded control rates 2 hours after removal of actinomycin from serial lines of green monkey kidney cells in exponentially dividing monolayer cultures. Enhanced synthesis was directly related to the dose of actinomycin, and release from inhibition was temperature dependent. A broad range of RNA sizes was made after removal of drug, but cytoplasmic and nucleolar sedimentation profiles were abnormal for at least 20 hours.
Differential dependence of regulatory volume decrease behavior in rabbit corneal epithelial cells on MAPK superfamily activation

Abstract We characterized the dependence of hypotonicity-induced regulatory volume decrease (RVD) responses on mitogen-activated protein kinase (MAPK) pathway signaling in SV40-immortalized rabbit corneal epithelial cells (RCEC). Following calcein-AM loading, RVD was monitored using a microplate fluorescence reader. Western blot analysis determined MAPK activation. After 30 min, the RVD response restored the relative cell volume to nearly isotonic values, whereas it was inhibited when cells were bathed either in a Cl−-free solution or with the Cl−-channel inhibitors: 5-nitro-2-(3-phenylpropylamino)benzoic acid or niflumic acid. Similar declines occurred with either a high-K+ (20 mM) supplemented solution or the K+ channel inhibitor 4-aminopyridine. Activation of extracellular signal-regulated kinase (ERK), p38, and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) was time and tonicity-dependent. Stimulation of ERK and SAPK/JNK was maximized earlier than that of p38. Activation of ERK and SAPK/JNK was insensitive to Cl− and K+ channel inhibitors, whereas inhibition with either PD98059 or SP600125, respectively, blocked RVD. However, inhibition of p38 with SB203580 had no effect on RVD. Suppression of RVD instead blocked p38 activation. Differences in the dependence of RVD activation on Erk1/2 and p38 signaling were validated in dominant negative (d/n)-Erk1 and d/n-p38 cells. Volume-sensitive Cl− and K+ channel activation contributes, in concert, to RVD in RCEC. Therefore, swelling-induced ERK and SAPK/JNK stimulation precedes Cl− and K+ channel activation, whereas p38 activation occurs as a consequence of RVD.
Enhancing optical isolator performance in nonreciprocal waveguide arrays.

We investigate the operation of optical isolators based on magneto-optics waveguide arrays beyond the coupled mode analysis. Semi-vectorial beam propagation simulations demonstrate that evanescent tail coupling and the effects of radiation are responsible for degrading the device’s performance. Our analysis suggests that these effects can be mitigated when the array size is scaled up. In addition, we propose the use of radiation blockers in order to offset some of these effects, and we show that they provide a dramatic improvement in performance. Finally, we also study the robustness of the system with respect to fabrication tolerances using the coupled mode theory. We show that small, random variations in the system’s parameters tend to average out as the number of optical guiding channels increases.
The phenomenology of seizures and epilepsy after stroke

Epilepsy and stroke continue to be cast in the spotlight of the public health arena as major causes of mortality and morbidity. Our understanding of these two disease processes has surged in recent years with many advances in diagnostic modalities and treatment strategies. Less understood is the relationship of seizures and epilepsy as they occur in the setting of stroke. Several studies have been published that examine the association between stroke and the ensuing seizure entity they create. However, in many of these investigations the conclusions reached have been variable. In this paper the authors have attempted to present a compilation of the work carried out to date on this subject. The topics addressed include the incidence of seizures and epilepsy after stroke and the factors that influence them, such as location, size, and type of stroke. The latency of seizures after stroke and their relationship to stroke location, risk of recurrent seizures, and subsequent mortality and morbidity are also presented. Other topics covered include the possible pathophysiologic mechanisms at play, the predictive value of electroencephalographic studies, and anticonvulsant treatment strategies. Finally, two instructive case reports have been included to further illustrate the relationship between seizures and stroke.
Building Capacity for Community Efficacy for Economic Development in Mississippi

In the present political environment, there is an interest in developing policies aimed at building capacity for community efficacy: the ability of a local population to come together and act collectively in pursuit of a generalized interest. In this study, we examine the extent to which variation in local conditions might account for variation in community efficacy for economic development in Mississippi. Drawing on multiple sources of data, the results clearly indicated that capacity for community efficacy rested on four major characteristics: (1) community social capital; (2) local civic physical infrastructure; (3) human and economic characteristics; and (4) community spatial characteristics.
3‐Methylcarboxy‐1H‐indazole. Theoretical study of its formation via intramolecular aliphatic diazonium coupling and x‐ray crystal structure

The methyl ester of 1H-indazole-3-carboxylic acid (2-Me) is formed in the diazotization of o-aminophenylacetic acid to o-diazoniumphenylacetic acid (1) in an intramolecular aliphatic diazonium coupling. 2-Me was identified and characterized by single-crystal x-ray diffraction and found to crystallize as hydrogen-bonded trimers of crystallographically independent molecules. The methylcarboxy groups are rotated slightly out of the best plane of the trimer resulting in only a pseudo-threefold axis. The crystal structure of 2-Me is compared with other indazoles and pyrazole. Regioselective electrophilic diazonium ion addition to the enol tautomer of 1 and subsequent hyrazone–azo tautomerization are proposed as a possible mechanism for indazole formation under acidic conditions. The tautomerization equilibrium between acetic acid and its enol 1,2-dihydroxyethene was studied and the effects of phenyl and o-diazoniumphenyl substitution on this equilibrium were explored with semi-empirical quantum mechanical methods. The performance of the semi-empirical method was assessed by comparison with ab initio and/or experimental data. It was found that the enol of o-diazoniumphenylacetic acid is stabilized greatly owing to extended conjugation and push–pull interactions in the enol form. These results suggest that the enol tautomer might be a viable reactive intermediate that warrants considerations in discussions of reaction mechanisms.
Fertile-Free Fast Lead-Cooled Incinerators for Efficient Actinide Burning

Fertile-free fast lead-cooled modular reactors are proposed as efficient incinerators of plutonium and minor actinides (MAs) for application to advanced fuel cycles devoted to transmutation. Two concepts are presented: (1) an actinide burner reactor, designed to incinerate mostly plutonium and some MAs, and (2) a minor actinide burner reactor, devoted to burning mostly minor actinides and some plutonium. These transuranics are loaded in a fertile-free Zr-based metallic fuel to maximize the incineration rate. Both designs feature streaming fuel assemblies that enhance neutron leakage to achieve favorable neutronic feedback and a double-entry control rod system that reduces reactivity perturbations during seismic events and flattens the axial power profile. A detailed neutronic analysis shows that both designs have favorable neutronic characteristics and reactivity feedback mechanisms that yield passive safety features comparable to those of the Integral Fast Reactor. A safety analysis presents the response of the burners to anticipated transients without scram on the basis of (1) the integral parameter approach and (2) simulations of thermal-hydraulic accident scenario conditions. It is shown that both designs have large thermal margins that lead to safe shutdown without structural damage to the core components for a large spectrum of unprotected transients. Furthermore, the actinide destructionmore » rates are comparable to those of the accelerator transmutation of waste concept, and a fuel cycle cost analysis shows the potential for economical accomplishment of the transmutation mission compared to other proposed actinide-burning options.« less
Trends in Urban American Psychiatry: Practice in Chicago in 1962 and 1973

A 1973 mailed survey of all psychiatrists practicing in Chicago utilized many questions identical to those used in a 1962 survey of this same population. By 1973, more psychiatrists were working in the public sector than in 1962, but by 1973, their interest in a social and community therapeutic orientation had decreased. The psychoanalytic orientation remained strong, though interest in analytic training had declined. In both private and organizational practice, the average Chicago psychiatrist was seeing more Blacks, poor people and Catholics, and fewer Jews, in 1973 than in 1962. Societal changes associated with these changes in psychiatric practice are discussed.
Paclitaxel and pegylated-liposomal doxorubicin are both active in angiosarcoma

Background Paclitaxel has unique activity in angiosarcomas of the face and scalp, but its activity in angiosarcomas originating at other sites is less well defined. Paclitaxel and pegylated-liposomal doxorubicin (PLD) are highly effective in Kaposi sarcoma (KS). Because of the efficacy of PLD in soft tissue sarcoma in general, and in KS in particular, coupled with potential similarities in KS and angiosarcoma, and the apparent activity of paclitaxel in angiosarcomas, the authors treated patients with angiosarcoma with either paclitaxel or PLD as initial chemotherapy. Methods To better define the efficacy of these agents in angiosarcoma, the authors reviewed their experience with paclitaxel and PLD in patients with angiosarcoma treated between 1994 and 2004. Results They identified seven patients with angiosarcoma treated with paclitaxel, and six treated with PLD. Only one patient in the series had an angiosarcoma of the scalp. Two patients receiving paclitaxel had received previous therapy with PLD, and four of six patients treated with PLD had previously received paclitaxel. Of the eight patients treated with paclitaxel, five had major responses (three had partial responses [PR] and two had complete disease remission [CR]) and three had progressive disease (PD). Of the 6 patients who received PLD, 3 had a PR for 6, 19, and >20 months, respectively, 2 had stable disease for 7 and 11 months, respectively, and 1 had PD. Conclusions The current study demonstrated the activity of PLD (five of six patients experienced clinical benefit) and extended the data on paclitaxel in angiosarcoma, both of the face and scalp, as well as angiosarcoma originating at other sites.
Reforming Reforms: Changing Incentives in Education Finance in Vermont

Abstract In 1997, Vermont passed Act 60, which reformed its education finance system to achieve greater equality of spending. The reform encouraged wealthy towns to reduce spending; it was politically unpopular and was replaced, in 2004, by Act 68. We analyze the spending incentives created by the two acts and estimate the effects the changewill have on spending inequality. Act 68 reduces tax prices for education spending in all towns, but reduces them disproportionately for wealthy towns. It increases education spending in Vermont but also increases inequality of spending. Because spending is inelastic with respect to tax prices, the increase in inequality is small relative to existing inequality. Our findings demonstrate that understanding the way towns respond to financial incentives, economically and politically, is critical in designing successful reforms. They suggest that it is difficult to maintain finance systems that give wealthy towns strong incentives to spend less or subsidize poorer towns. U...
COMPARISON OF TWO METHODS OF SELECTING SMOOTHING SPLINE FUNCTIONS FOR ESTIMATION OF SPECIFIC RATES IN FERMENTATIONS

Abstract A new method of selecting smoothing spline functions is presented and used to curve fit experimental fermentation data. From the curves generated, estimates for the specific growth rate, the specific rate of substrate utilization and the biomass energetic yield are made. Selection of the smoothness parameters is based on minimization of a response surface fit to the smoothness parameters used to generate the time profiles of biomass and substrate concentration. The response modelled is the extent of closure of the carbon balance and the available electron balance. Results obtained using cross validation for selection of the smoothness parameter are also presented, and compared to the results calculated using the response surface technique. Estimates made for specific growth rate and biomass energetic yield are used with the covariate adjustment procedure to calculate point and 95% confidence interval estimates for the true biomass energetic yield, ηmax, and the maintenance coefficient, me. The re...
Last of the enlightened despots: A comparison of President Mikhail Gorbachev and Emperor Joseph II

Abstract The Austrian and Holy Roman Emperor, Joseph II, has been proclaimed by some scholars as having been the “last of the enlightened despots.” However, it is possible to draw parallels between the political and theoretical climate of Austria during the Age of Enlightenment and a similar climate that prevailed during the final years of the Soviet Union, during the presidency of Mikhail Gorbachev. While many specific conditions, policies, and results of these two societies and leaders are not historically compatable, their overall approach and tone share striking characteristics which, though broad, merit further consideration. From such an analysis it may be possible to reach certain broad conclusions regarding the nature of political leadership and liberal democratic reform.
Modifying Dew-Retted Flax Fibers by Means of an Air-Atomized Enzyme Treatment

The use of atomization or an aerosol formation is investigated as a vehicle for enzyme treatment of dew-retted flax fibers. A cellulase/endoglucanase from Trichoderma reesei is applied by atomizati...
Optical Communication Through Low-Visibility Weather

By exploiting the scattered light, it is possible to improve atmospheric optical communication through low-visibility weather. This paper summarizes the multiple-forward-scatter propagation model for a line-of-sight optical link operating in low-visibility weather. Using this model, digital communication performances for diffraction-limited and wide field-of-view receivers are compared. It is shown that background-light suppression is the key to extended link operability in the daytime. Recent work on space-distributed phase compensation techniques for achieving this suppression is described.
Effects of angiotensin II and bladder condition on hydration behavior and water uptake in the toad, Bufo woodhousei.

Abstract 1. 1. Water absorption response (WR) behavior and water weight gain were examined in hydrated toads, Bufo woodhousei , treated with angiotensin II (All) or with a control Ringer's solution. The effects of urinary bladder condition ( ad lib . bladder urine or empty bladder) were examined concurrently. 2. 2. Toads treated with All (100μg/100g body weight), spent more time in WR posture and absorbed more water than Ringer's-injected toads. 3. 3. Toads with empty bladders maintained WR posture for longer periods of time and gained more weight than toads whose bladders were not emptied. 4. 4. The effects of All and bladder urine on water absorption by B. woodhousei appear to be separate and additive.
The Role of Apparent Constraints in Normative Reasoning: A Methodological Statement and Application to Global Justice

The assumptions that are made about the features of the world that are relatively changeable by agents and those that are not (constraints) play a central role in determining normative conclusions. In this way, normative reasoning is deeply dependent on accounts of the empirical world. Successful normative reasoning must avoid the naturalization of constraints and seek to attribute correctly to agents what is and is not in their power to change. Recent discourse on global justice has often come to unjustified conclusions about agents’ obligations due to a narrow view of what is changeable and by whom.
On permanental compounds

Abstract If k ⩽ n , then G k , n denotes the set of all strictly increasing functions from { 1 , 2 , … , k } to { 1 , 2 , … , n } ordered lexicographically. If A = [ a ij ] is an n × n complex matrix, then A [ α ∣ β ] denotes the k × k submatrix of A whose rows and columns are specified by α and β , respectively, and A ( α ∣ β ) is the corresponding complementary submatrix of A. The k-th permanental compound, CP k ( A ) , of A is the n k × n k matrix indexed by the members of G k , n such that ( CP k ( A ) ) α , β = per ( A [ α ∣ β ] ) for all α , β ∈ G k , n . Much work has been done on permanental compounds. We consider the n k × n k matrix C k ( A ) such that ( C k ( A ) ) α , β = per ( A ( α ∣ β ) ) per ( A [ α ∣ β ] ) . In 1986 Bapat and Sunder [1] conjectured that if A is positive semi-definite and Hermitian, then per ( A ) is the largest eigenvalue C 1 ( A ) . We extend the conjecture to all of the matrices C k ( A ) where 1 ⩽ k ⩽ n . We show how our extended conjecture is related to a theorem of this author, and derive several inequalities. For example, we show that if x is a ( 0 , 1 ) -vector, then 〈 C k ( A ) x , x 〉 ⩽ ‖ x ‖ 2 per ( A ) for all positive semi-definite A.
Muscle cell death during the development of head and neck muscles in the chick embryo

Degenerating myofibers have been reported in the embryos and neonates of a number of birds and mammals, but neither the pervasiveness of the phenomenon nor the spatiotemporal patterns of degeneration has been examined in detail. Using transmission electron microscopy, we determined the patterns of muscle cell death in the chick biventer cervicis, a head extensor muscle. Cell death is most pronounced at incubation days 10 through 15, and occurs throughout the muscle. This is the period during which many myofiber clusters segregate into individual fibers, each with a separate basal lamina, and secondary myofibers become demarcated. Cells of largest diameter, presumably the primary myofibers, are preferentially affected. Degenerating cells exhibit a cohort of cytological features consistent with apoptosis, including the presence of dense, darkly-staining, hypercontracted myofibrils, misshapen nuclei with irregular chromatin condensations along the nuclear envelope, and scores of cytoplasmic vesicles and vacuoles. In cross section some large diameter muscle cells are characterized by sparse, flocculent cytoplasm that is devoid of myofibrils and organelles. Some show disintegrating cell membranes. In longitudinal section 200–300 μm long regions of hypercontracted myofibrils alternate with areas devoid of fibrils; this arrangement suggests that the myofibrils break into segments that are in register along one part of a muscle fiber and entirely absent from the adjacent length of fiber. We have observed similar patterns of muscle cell degeneration in the complexus, splenius cervicis, depressor mandibulae, and branchiomandibularis muscles. By day 18 of incubation most signs of degeneration are absent and by hatching (day 21) the muscle fibers all appear healthy. Many of these cytological changes in embryonic head muscle cells are characteristic of programmed cell death. We hypothesize that large-scale death of myocytes is a normal part of avian myogenesis and an important mechanism for affecting the transformation from embryonic to hatching muscle patterning. © 1995 Wiley-Liss, Inc.
Response of Martian ground ice to orbit‐induced climate change

[1] Variations in the orbit and spin axis of Mars drive climate changes that affect both surface temperatures and atmospheric water content, both of which affect the distribution of ground ice. A simple technique is presented to determine the atmospheric water content for different epochs, on the basis of the water carrying capacity of the atmosphere over surface ice. Also presented is a technique to correct the water vapor density just above the surface for depletion due to nighttime frost, reducing the effective water vapor density in contact with ground ice. Distributions of stable ground ice are generated for the present epoch with varying amounts of water vapor in the atmosphere; water vapor depletion restricts the extent of stable ground ice and ice never becomes stable at low latitudes. As the position of perihelion varies, the extent of ground ice changes several degrees in latitudinal extent. The extent of ground ice is more sensitive to obliquity; however, high obliquities are still not able to make ground ice stable at low latitudes. The finding that ice is never stable at low latitudes is consistent with the absence of ice-related landforms, like terrain softening, at low latitudes. Correlations exist between the extents of stable ground ice and the distribution of various styles of mantle deposits.
Algebraic, differential, and integral relations for membranes in series and other multilaminar media: Permeabilities, solute consumption, lag times, and mean first passage times

The problem of transport with possible solute binding and consumption is considered for membranes in series, as well as other multilaminar media, in which transport and reaction processes are linear and time invariant. By analogy with electrical networks, the properties of a membrane are summarized by an admittance (or alternatively, impedance) matrix that relates fluxes to concentrations on either side of the membrane
Revealing pyrolysis chemistry for biofuels production: Conversion of cellulose to furans and small oxygenates

Biomass pyrolysis utilizes high temperatures to produce an economically renewable intermediate (pyrolysis oil) that can be integrated with the existing petroleum infrastructure to produce biofuels. The initial chemical reactions in pyrolysis convert solid biopolymers, such as cellulose (up to 60% of biomass), to a short-lived (less than 0.1 s) liquid phase, which subsequently reacts to produce volatile products. In this work, we develop a novel thin-film pyrolysis technique to overcome typical experimental limitations in biopolymer pyrolysis and identify α-cyclodextrin as an appropriate small-molecule surrogate of cellulose. Ab initio molecular dynamics simulations are performed with this surrogate to reveal the long-debated pathways of cellulose pyrolysis and indicate homolytic cleavage of glycosidic linkages and furan formation directly from cellulose without any small-molecule (e.g., glucose) intermediates. Our strategy combines novel experiments and first-principles simulations to allow detailed chemical mechanisms to be constructed for biomass pyrolysis and enable the optimization of next-generation biorefineries.
O significado da compra: desejo, demanda e o comércio do sexo

Feminists and other scholars have debated theoretically what exactly is being purchased in the prostitution transaction and whether sex can be "a service like any other", but they have scarcely tackled these questions empirically. This article draws upon field observations of and interviews with male clients of commercial sex-workers and state agents entrusted with regulating them to probe the meanings given to different types of commercial sexual exchange. Manifested by client arrests and re-education, vehicle impoundment, stricter laws on underage prostitution and the possession of child pornography, recent state efforts to problematize male sexuality throughout the USA and Western Europe have been developed alongside an increasingly unbridled ethic of sexual consumption, as evidenced by soaring demand for pornography, strip clubs, lap-dancing, escorts, telephone sex and "sex tours" in developing countries. By situating commercial sexual exchange within the broader context of post-industrial transformations of culture and sexuality, we can begin to unravel this paradox.
Continuum coupled cohesive zone elements for analysis of fracture in solid bodies

Abstract Embedding cohesive surfaces into finite element models is a widely used technique for the numerical simulation of material separation (i.e. crack propagation). Typically, a traction–separation law is specified that relates the magnitude of the cohesive traction to the distance between the separating surfaces. Thus the characterization of fracture in such models is not directly coupled to the bulk constitutive response, in the sense that the cohesive traction does not explicitly depend on material stretching in the plane of the fracture surface. In this work, an initially-rigid cohesive-traction formulation that is coupled to the surrounding continuum is introduced as a further development of the cohesive zone idea. In this model, the traction–separation law – and therefore the fracture phenomenology – derives directly from the bulk constitutive law. The immediate goal is an improved cohesive zone framework that naturally and logically initiates cohesive separation behavior, and couples its evolution to the material state in the region of the crack tip. A cohesive element based on this model is implemented in an explicit three-dimensional finite element code. Proof-of-concept analyses using both linear elastic and Gurson void growth constitutive relations are presented. A three-point bend simulation is found to give good agreement with experimental results.
EPR Free Induction Decay Coherence Observed after a Single Pulse in Saturation Recovery Experiments for Samples with Resolved Multiline CW Spectra

An electron paramagnetic resonance (EPR) spin-coherence signal has been observed following a single pulse for rapidly tumbling radicals with well-resolved nuclear hyperfine splitting in fluid solution when B 1 is large enough to excite multiple hyperfine lines. This signal, which has the shape of a spin echo, arises from constructive interference of overlapping free induction decays (FIDs) from the hyperfine lines. It has been observed for 2,6-di-t-butyl-1,4-benzosemiquinone, 2,5-di-t-butyl-1,4-benzosemiquinone, 2,3,5,6-tetramethoxy-1,4-benzosemiquinone, 2,4,6-tri-t-butylphenoxyl radical, and 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxy. It occurs at a time after the pulse that is equal to the inverse of the nuclear hyperfine splitting, independent of EPR resonance frequency from 250 MHz to 9.1 GHz. As the length of the pulse is increased, separate coherence signals can be observed that correspond to the beginning and end of the pulse. This coherence is distinct from the "single-pulse echo" signals discussed in the literature. For 2,6-di-t-butyl-1,4-benzosemiquinone, which has two resolved couplings (1.24 and 0.052 G), FID oscillations with a period that corresponds to the larger hyperfine coupling are observed on the coherence signal that arises from the smaller hyperfine coupling. If phase cycling is not perfect, the coherence signal can interfere with measurements of T 1 by saturation recovery.
Using Cultural Artifacts to Change and Perpetuate Strategy

Abstract This case study portrays the critical role played by cultural artifacts in perpetuating old strategies and in executing new ones. It provides a longitudinal perspective on how cultural artifacts have been used in an MBA program based in the United States to both perpetuate and change strategy. The study also provides numerous examples of how cultural artifacts have been utilized in achieving both of these purposes so that others may employ cultural artifacts in a similar fashion. A considerable number of examples are provided in a table, which is readily useable to guide the reader's efforts. Little attention has been paid to cultural artifacts and their impact on the change process. It is quite clear to us that this impact is significant, and manageable. This study introduces several new facets in the exploration of organizational cultural artifacts. Practically speaking, managers need to be more aware of the power of cultural artifacts, they need to learn how to use them, and they need to pract...
Bis(pyridyl)-silane and -methanol ligands IV. Catalytic application of nickel(II) complexes in the Kumada cross-coupling reaction

Abstract Treatment of the bis(2-pyridyl)silane ligands MeRSi(2-C5H4N)2 with (MeCN)2-NiBr2 afforded {MeRSi(2-C5H4N)2}NiBr2 (3a, R = Me; 3b, R = Ph) in excellent yield. The latter complexes were bright purple crystalline solids with paramagnetic line broadening in the NMR spectra; although, no ESR signal could be detected in solution or in the solid state. Complex 3a was found to be an effective catalyst for the cross-coupling of Grignard reagents with aryl and vinyl halides. The catalytic system also coupled alkyl Grignard reagents with chlorobenzene provided a dipolar aprotic solvent such as HMPA was employed. Optically pure ligands, {6-alkoxy-2-pyridyl}(Ar)CH(OMe) (5), were employed in the asymmetric cross-coupling reaction of (1-phenylethyl)magnesium chloride and bromoethene. Conversion of the Grignard reagent ranged from 73 to 88% with ∼50% chemical yields of 3-phenyl-1-butene with optical yields ranging from ∼0 to 11%.
Pediatric chest wall Ewing's sarcoma

Abstract Background: Chest wall tumors of primitive neuroectodermal origin (PNET, Ewing's sarcoma [ES]) are rare and have a poor prognosis. Multimodality therapy has improved survival results, and long-term survival is possible. Whether adjuvant radiation therapy is uniformly beneficial remains unclear. Methods: A retrospective analysis of the authors' institutional experience between 1979 and 1998 was performed. Results: Twenty consecutive patients with PNET-ES of the chest wall were identified. The median age was 12 years (range, 2.5 to 21 years). Median follow-up was 3 years (range, 7 months to 19.4 years). Seven patients presented with a mass, 12 with pain, 1 with respiratory distress, and 1 with a neuropathy. Initial therapy consisted of biopsy and neoadjuvant chemotherapy followed by chest wall resection in 12 patients. Of the remaining 8 patients, 6 underwent biopsy, followed by chest wall resection and adjuvant chemotherapy, 1 underwent biopsy, chemotherapy, and resection of a lung nodule, and 1 underwent biopsy, chemotherapy, and a laminectomy and decompression procedure. All 20 patients were included in institutional-based trials using multiagent chemotherapy. Fifteen patients received radiation therapy with a median dose of 3,000 cGy. At last follow-up, 11 patients are alive and disease free, with a median survival of 7.5 years (range, 7 months to 19.4 years). Seven of 11 (64%) survivors had neoadjuvant therapy followed by chest wall resection. Seven of 11 (64%) survivors had radiation therapy. There was no surgical mortality. Twelve patients had treatment-related complications, 3 of which were related to surgical resection. There were no survivors among patients with recurrent disease. Three of the patients who died of disease had both local and distant recurrences, 4 patients had distant recurrence only, and one patient had local recurrence only. Only 4 of 9 (44%) patients who died were treated initially with chemotherapy followed by chest wall resection. All but 1 of those that died (89%) received initial radiation therapy. All 9 patients who did not survive received additional salvage radiotherapy as well. Conclusions: Long-term survival is possible with ES-PNET after complete chest wall resection. This may be facilitated by neoadjuvant chemotherapy. Long-term survival without radiation therapy is possible, and consideration of radiation therapy should be made on a case-by-case basis. J Pediatr Surg 35:550-555. Copyright © 2000 by W.B. Saunders Company.
AN ANALYSIS OF DAILY REPORT CARDS AND PARENT‐MANAGED PRIVILEGES IN THE IMPROVEMENT OF ADOLESCENTS' CLASSROOM PERFORMANCE

A daily report-card system, involving home privileges administered by parents, was developed for use with "problem" junior-high students. In Experiment I, when home privileges and parent praise were contingent on improved school conduct, classwork, daily grades, and teacher satisfaction, the school performance of three students improved considerably. In Experiment II, a similar report-card system was employed with two additional students, except only parent praise was contingent on improved school performance. Under these conditions, one of the students did not bring the report card home, and class performance did not improve until contingent home privileges were added. The school performance of the second student improved with the card and praise alone. However, there appeared to be a slow decline of classwork performance over time. For Experiment III, an instructional manual, describing the report-card program, was written for school guidance counsellors. Two guidance counsellors read the program, used it with one student each, and found that the school performance of both students improved. These results suggest that the daily report-card program with home consequences administered by parents can improve the school performance of, and teacher satisfaction about, students having considerable difficulty in school.
Facile synthesis of homoallylic alcohols from aldehyde acetals in water

Homoallylic and bis-homoallylic alcohols, which are widely used in organic synthesis, were prepared in good yields by a facile allylation of aldehyde acetals with allyl bromide, tin(II) chloride and potassium iodide in water.
Substituted benz[a]acridines and benz[c]acridines as mammalian topoisomerase poisons.

Coralyne and several other synthetic benzo[a,g]quinolizium derivatives related to protoberberine alkaloids have exhibited activity as topoisomerase poisons. These compounds are characterized by the presence of a positively charged iminium group, which has been postulated to be associated with their pharmacological properties. The objective of the present study was to devise stable noncharged bioisosteres of these compounds. Several similarly substituted benz[a]acridine and benz[c]acridine derivatives were synthesized and their relative activity as topoisomerase poisons was determined. While the benz[c]acridine derivatives evaluated as part of this study were devoid of topoisomerase poisoning activity, several dihydrobenz[a]acridines were able to enhance DNA cleavage in the presence of topo I. In contrast to certain protoberberine derivatives that did exhibit activity as topo II poisons, none of the benz[a]acridines derivatives enhanced DNA cleavage in the presence of topo II. Among the benz[a]acridines studied, 5,6-dihydro-3,4-methylenedioxy-9,10-dimethoxybenz[a]acridine, 13e Scheme 2. Figure options Download full-size image Download high-quality image (263 K) Download as PowerPoint slide , was the most potent topo I poison, with comparable potency to coralyne. These data suggest that heterocyclic compounds structurally related to coralyne can exhibit potent topo I posioning activity despite the absence of an iminium cation within their structure. In comparison to coralyne or other protoberberine derivatives, these benz[a]acridine derivatives possess distinctly different physicochemical properties and represent a novel series of topo I poisons.
Impact and Assessment of Measurement Systems that Meet the 4:1 Rule

This article considers the impact of a measurement system that meets the 4:1 rule. Probabilities of accepting a bad part and rejecting a good part are evaluated. A simulation study calculates the increased estimates of the population standard deviation when the measurement error is ignored, where both non-trending and trending populations are considered. Also, the impact of sample size is evaluated on estimates and upper confidence bounds of the measurement system standard deviation that are used to assess the 4:1 rule capability; both measurement systems from a single and multiple sources of variation are explored. Copyright © 2014 John Wiley & Sons, Ltd.
Help is in the Helping: An Evaluation of Help Documentation in a Networked Age

People use software in service of complex tasks that are distributed over sprawling and idiosyncratically constructed technological and social networks. The aims and means of carrying out those tasks are not only complex but uncertain, which creates problems for providing help if the tasks, starting points, and endpoints cannot be assumed. Uncertain problems are characteristic of networks, and software forums stand out as effective public spaces in which help can be pursued in a network fashion that differs from traditional help documentation. This article describes the results of a quantitative descriptive study of such practices in four software forums.