cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of Na in polycrystalline and epitaxial single-crystal CuIn1−xGaxSe2

Na is found to improve the performance of Cu(In,Ga)Se2 (CIGS) solar cells although the mechanism is not clear. This paper briefly reviews some of the observations on Na in CIGS polycrystalline and epitaxial films. Experiments suggest weak electrical effects of Na within grains, primarily by reducing compensation and in some cases by enhancing acceptor concentrations. As it segregates to surfaces, it has been suggested that Na acts through passivation of grain-boundary defects. However, its main effect is on device open-circuit voltage (and somewhat on fill factor), which does not correlate with grain size but rather with bulk grain defects. The Na concentration scales somewhat with grain boundary density averaged over large areas of film, suggesting that it may be active there. Modest Na concentrations often increase grain size in polycrystals, although not when the grain size is already large, and often changes preferred orientation. Na segregates to the surfaces of CIGS grains. These results suggest that it may act at the surface, modifying growth mechanisms or defect organization during growth. TEM evidence shows that strong concentration of Na in the grain boundaries, sufficient to passivate surface defects by itself, is unlikely to occur. Finally, Na is removed from the surface of CIGS by aqueous solutions, such as those used to form the heterojunction. It is concluded that Na acts at the surface during growth to organize point defects, probably including by reduction of vacancy populations, within the bulk grains but that it has no residual effect once growth is complete.
Using neutron stars and primordial black holes to test theories of quantum gravity

Three observational tests of cosmological natural selection, a theory that follows from some hypotheses about quantum gravity, are described. If true, this theory explains the choices of the parameters of the standard model of particle physics. The first, the observation of a pulsar with mass greater than 2.5M◦, would cleanly refute the theory. The second and third, having to do with primordial black holes and early massive star formation, could do so given likely developments in the near future. However given present knowledge these arguments do not presently refute the theory. This shows that cosmological natural selection has not so far been refuted,while remaining very vulnerable to falsification by possible observations.
Procurement, Incentives and Bargaining Friction: Evidence from Government Contracts

A transaction cost theory of procurement developed by Bajari and Tadelis (2001) models the buyer’s choice of incentive structure as endogenous, with buyers trading o the eciency of high-powered incentives against the ex post bargaining friction these incentives can create. The source of the bargaining friction is assumed to be asymmetric information between the buyer and seller about the true costs of adapting the project to changed conditions. Using government contract data and an instrument based on contracting-oce idiosyncratic variation
Presintering Heat Treatment, Densification, and Mechanical Properties of Silicon Carbide

Silicon carbides were subjected to extended heat treatments at 1,400 or 1,500 C prior to a 1-h isochronal sintering at 2,000 C in argon, and the resulting microstructures, final densities, and room-temperature four-point bend strengths were compared to those of samples prepared without the pretreatments. The samples heat-treated at 1,600 C exhibited higher relative densities and flexure strengths. Microstructural observation revealed that the heat treatment at 1,600 C modified the initial powder compact microstructure, decreasing the development of large, dense domains in the early and intermediate sintering stages. This evolution was considered to promote a more uniform subsequent densification. The final size and distribution of the grains as well as of the pores were found to be affected favorably by the pretreatment.
Numerical Methods of Noise Reduction for Frequency Domain SEM

ABSTRACT This paper addresses the numerical problem of performing a pole residue expansion on noisy data. A method of combining dissimilar data sets to achieve an effective increase in signal-to-noise ratio is tested on computer generated data simulating scattering from a sphere and from a thin wire. The data is corrupted with white Gaussian noise and the algorithm is tested for signal-to-noise ratios ranging from -10 dB to 60 dB. An iterative version of the algorithm is also tested. Finally, the problem of filtering noise from relatively quiet data is discussed and a novel filtering algorithm is presented.
Structural Studies of Two Isoelectronic Tetrakis Isocyano Complexes

Two isoelectronic tetrakis isocyano compounds, tetra(p-isocyanoanisole)nickel(0) and tetra(p-isocyanoanisole)copper(I) hexafluorophosphate were synthesized from nickel bis cyclooctadiene and copper (I) tetra acetonitrile hexafluorophosphate and the isonitrile, respectively, and their structures were determined. The nickel complex crystallizes in the orthorhombic space group P212121 with a = 9.6709(8), b = 15.2324(13), c = 19.0955(16) A and Z = 4. The copper salt forms crystals with a tetragonal setting in P4/n with a = b = 15.8206(5), c = 6.5848(4) A and Z = 2. Both complexes exhibit the approximate tetrahedral coordination environment expected for 18 valence electron complexes with soft σ-donor π-acceptor ligands. Packing in the nickel complex is dominated by weak π–π stacking, C–H···πphenyl, and C–H···π interactions towards the isonitrile carbon and nitrogen atoms, and several slightly stronger C–H···O interactions. In the copper complex the presence of the PF6 anion allows for the formation of stronger C–H···F interactions, and these in combination with π–π stacking and C–H···O hydrogen bonds dominate the packing. The X-ray crystal structures of two isoelectronic homoleptic tetrakis isocyano complexes, tetra(p-isocyanoanisole)nickel(0) and tetra(p-isocyanoanisole)copper(I) hexafluorophosphate, are reported. Packing is dominated by C–H···O, π···π stacking and C–H···π interactions for the nickel complex and by π···π stacking, C–H···O and C–H···F interactions in the structure of the copper salt.
The Dependence of Welfare Upon Virtue

In this article, I articulate a modest form of welfare perfectionism, according to which (1) the virtuous person’s welfare is an aspect of her virtuous activity, and (2) the virtuous person will never be in position to choose to attain welfare at the expense of acting virtuously. I then defend these claims against a range of objections.
The Invariance of the Factorial Validity of the Metropolitan Readiness Tests for Blacks, Whites, Males, and Females

The six subtests comprising the Metropolitan Readiness Tests were factor analyzed separately for white females, white males, black females, and black males. A single factor best described the structure of the test for each group. Coefficients of congruence for the factor between each pair of groups always exceeded .92. Thus, the factor structure of the Metropolitan Readiness Tests is essentially invariant with regard to race and sex variables.
Quantitation of Multiple Sphingolipid Classes Using Normal and Reversed-Phase LC–ESI–MS/MS: Comparative Profiling of Two Cell Lines

Sphingolipids are an important class of compounds that regulate signal transduction and other vital cellular processes. Herein, we report sensitive normal and reversed phase LC–MS/MS methods for quantitation of multiple sphingolipid classes. In the normal-phase ESI/MS/MS method, a high content of organic solvents was utilized, which, although it included hexane, ethyl acetate, acetonitrile containing 2% methanol, 1–2% acetic acid, and 5 mM ammonium acetate, resulted in a very efficient electrospray ionization of the ceramides (Cers) and hexosylceramides (MHCers). Three normal-phase LC–MS/MS methods using segmented phases were developed to specifically target Cers, MHCers, or sphingomyelins (SMs). This segmentation scheme increases the number of data points acquired for a given analyte and enhances the sensitivity and specificity of the measurements. Nine separate reversed phase chromatography methods were developed for the three classes of compounds. These assays were used for comparing the levels of Cers, SMs, and MHCers from mouse embryonic fibroblast (pMEF) and human embryonic kidney (HEK293) cells. These findings were then compared with the reported data from RAW264.7 mouse macrophage cells, BHK21 hamster cells, and human plasma and serum samples. The analysis of cell lines, using both normal and reversed phase chromatography, revealed discrimination based on the type of chromatography chosen, while sphingolipid assays of samples containing different amounts of protein showed different results, even after normalizing for protein content. Also, LC/MS/MS profiles were provided for the classes and individual compounds so that they could be used as “molecular profiles” for class or individual sample analysis.
Fungal communities influence root exudation rates in pine seedlings

Root exudates are hypothesized to play a central role in belowground food webs, nutrient turnover, and soil C dynamics in forests, but little is known about the extent to which root-associated microbial communities influence exudation rates in trees. We used a novel experimental technique to inoculate loblolly pine (Pinus taeda L.) seedlings with indigenous forest fungi to examine how diverse fungal communities influence exudation. Surface-sterilized seeds were sown in intact, unsieved soil cores for 14 weeks to promote root colonization by fungi. After 14 weeks, we transferred seedlings and root-associated fungi into cuvettes and measured exudate accumulation in trap solutions. Both the abundance and identity of root-associated fungi influenced exudation. Exudation rates were greatest in root systems least colonized by ectomycorrhizal (ECM) fungi and most colonized by putative pathogenic and saprotrophic fungi. However, the ECM community composition was not a strong determinant of exudation rates. These results suggest that environmental conditions that influence the degree to which tree roots are colonized by pathogenic and saprotrophic vs. mutualistic fungi are likely to mediate fluxes of labile C in forest soils, with consequences for soil biogeochemistry and ecosystem processes.
PIWI proteins and PIWI-interacting RNAs in the soma

The discovery of millions of PIWI-interacting RNAs revealed a fascinating and unanticipated dimension of biology. The PIWI-piRNA pathway has been commonly perceived as germline-specific, even though the somatic function of PIWI proteins was documented when they were first discovered. Recent studies have begun to re-explore this pathway in somatic cells in diverse organisms, particularly lower eukaryotes. These studies have illustrated the multifaceted somatic functions of the pathway not only in transposon silencing but also in genome rearrangement and epigenetic programming, with biological roles in stem-cell function, whole-body regeneration, memory and possibly cancer.
A fine-grain modular detector for low-energy particles

Abstract The design and performance of a fine-grain detector with a mass of 20 tons, composed of liquid scintillator and proportional drift chamber planes, are described.
Miscibility studies in blends of polybenzimidazoles and poly(4‐vinyl pyridine)

Poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole] (PBI) is shown to be miscible with poly(4-vinyl pyridine) over the entire composition range. Experiments were performed with commercial PBI as well as a lower molecular weight material synthesized by us. Blend miscibility is evidenced by single glass transition temperature intermediate between the pure polymers. Hydrogen bonding between the components was detected by infrared spectroscopy.
An ethical challenge in critical care: the severely injured patient.

Abstract Concurrent with the enormous advances in critical care medicine, an immense literature has evolved extolling the notions of patient autonomy and death with dignity as curbs on the inappropriate pursuit of such new opportunities. The new ethos of patient autonomy has a great deal of merit. It also lacks clinical nuance and realism in certain types of cases. This yields inappropriate clinical results and unethical management. This article argues for a form of therapeutic activism that this new ethos seems to condemn. This activism is especially appropriate for certain types of severely injured patients.
Acute adaptive responses of central sensorimotor neurons after spinal cord injury

Spinal cord injury (SCI) can be a lifelong, devastating condition for both the patient and the caregiver, with a daunting incidence rate. Still, there are only limited available therapies and the effectiveness of precise regeneration within the central nervous system is minimal throughout postnatal life. Recently, improved regeneration after SCI was seen by manipulating a pathway in sensorimotor neocortices that is involved in phosphorylation of an RNA binding protein (RBP) required for mRNA translation, the Eukaryotic translation initiation factor 4E (eIF4E). Our data identifies rapid molecular alterations of eIF4E in the sensorimotor neocortices 1 and 3 days after a lateral hemisection SCI, used as a model for Brown-Sequard syndrome. The function of an RBP depends on both its distribution sites within the cell and its phosphorylation states. Indeed, we found both to be affected after SCI. There was a distinct subcellular redistribution of eIF4E and phosphorylated-eIF4E was reduced, indicating that the eIF4E’s translation was disrupted. Upon identification and analysis of the mRNA cargo of eIF4E in uninjured sensorimotor neocortices, we found that eIF4E binds both Importin-13 (Ipo13) and Parvalbumin (Pv) mRNAs, indicating a role in their translation. Remarkably, eIF4E’s interaction with both Ipo13 and Pv mRNAs was disrupted 1 and 3 days after SCI, despite preservation of total Ipo13 and Pv mRNA levels. Finally, we detected a selective loss of expression of both IPO13 and PV proteins in projection neurons of sensorimotor neocortices, as well as their disrupted dendritic polarity. Since IPO13 is predominantly expressed in neocortical projection neurons and PV in a subset of neocortical interneurons, these data suggest a strong acute effect of SCI on neocortical microcircuitry. Taken together, these data indicate that neocortical eIF4E and a subset of mRNAs may be rapidly recruited to translational machinery after SCI to promote adaptive regeneration response of sensorimotor neurons.
Tailored Precision Armies in Fully Networked Battlespace: High Reliability Organizational Dilemmas in the ‘Information Age’

A vision of information age technology providing the ability to closely manage environmental uncertainties pervades current changes in Western militaries. The goal is to digitally link every weapon system in battlespace to effect real-time synchronization and response and just-in-time logistics and supply. Such optimism ignores organizational implications as well as the uncertainties of battlefield conditions. To be effective, the envisioned precision army will require levels of environmental and organizational certainty unprecedented in either military or civilian history. Fast, reliable, invulnerable resource linkages, the ability to minimize casualty loss and innovative episodic behaviours in response to inherently unpredictable ground conditions will all be essential. Success will depend on the extent to which military organizations succeed in reproducing the conditions and/or emulating the characteristics of high reliability organizations. This reproduction or emulation, however, is particularly difficult to achieve given the uncertainties of large scale, non-repetitive activities under hostile terrain-dependent conditions typical of the ground battlefield. Over time, such forces will lack the slack necessary to survive in battle. Rather than the emergence of a more effective and reliable organization, the more likely outcomes are avoidance of risky operations and an ineffective mimetic isomorphism of the air forces on which the ground forces will increasingly depend. The primary object of organization is to shield people from unexpected calls upon their powers of adaptability, judgment and decision (Hamilton, 1921:62)
Decoding strategies as predictors of reading skill: A follow-on study

A follow-on study was conducted on first- and third-grade children who were tested on the Word Identification subtest of the Woodcock Reading Mastery Test. Errors were phonetically transcribed and proportions of total errors were assigned to one of four strategy types based upon the type of decoding analysis: whole word, part word, and either probable (legal) or improbable (illegal) phonetic decoding. The type of strategy employed was highly correlated with concurrent reading test scores and predicted 30 to 37% of the variance in word recognition 19 months later. Use of phonetic decoding was a strong positive predictor and whole word decoding a negative predictor at both first and third grade. Part word decoding became a negative predictor at third grade. Nearly all children used more than one strategy and there was a developmental trend to shift to a phonetic strategy. But this shift was not inevitable and had not occurred for 31% of the children at the close of the study. Children who stayed with the most inefficient strategies had significantly higher vocabulary scores and equivalent phonemic processing ability when compared to readers with more efficient decoding strategies.
The Problems of Textile Information Retrieval1

Many problems areas in the field of textile information are outlined. Input is considered, with emphasis on coordination with other information systems. The needs of users are considered and the nature of indexing to meet these needs. The role of a textile thesaurus in indexing and searching is described. Reference searching and the use of bibliographic data are reviewed. Directions for further study are suggested.
Dynamic Response of a Circular Beam on a Wieghardt‐Type Elastic Foundation

Starting from the two dimensional formulation of the Wieghardt-type elastic foundation, the deflection of the foundation surface subjected to an arbitrarily distributed circular load is determined using the method of harmonic analysis. Based on this result, the dynamic response of a circular beam resting on a Wieghardt-type elastic foundation and subjected to a harmonic load is obtained. Numerical results are plotted for the free vibration as well as for the two types of forced vibration of the circular beam. Ausgehend von der zweidimensionalen Behandlung der Wieghardtschen elastischen Unterlage wird die vertikale Verschiebung der Unterlagenflache mit Hilfe der harmonischen Analyse angegeben. Es wird angenommen, das die Unterlage mit einer auf einem Kreisring beliebig verteilten Linienlast belastet ist. Unter Benutzung dieser Untersuchung wird das dynamische Verhalten der harmonischen Last eines tragenden Kreisringbalkens auf einer Wieghardtschen elastischen Unterlage bestimmt. Numerische Ergebnisse werden fur die freie Schwingung und fur zwei Falle der Zwangsschwingung graphisch dargestellt.
Does Vitamin D Make the World Go ‘Round’?

Abstract Vitamin D has emerged from obscurity, and its effects on various organ systems throughout the body down to the cellular level are being discovered. What was once thought to be a simple hormone affecting only bone and calcium metabolism has shifted. We no longer see vitamin D as a “vitamin” important only in childhood, but as a complex hormone that is involved not only in calcium homeostasis but also in the integrity of the innate immune system. Vitamin D deficiency is linked to inflammatory and long-latency diseases such as multiple sclerosis, rheumatoid arthritis, tuberculosis, diabetes, and various cancers, to name a few. In this review, we trace how we came to view vitamin D and how that view led to one of the largest epidemics of nutrient deficiency beginning in the late 20th century. We then discuss the needs of vitamin D in the context of the breastfeeding mother and her infant and child, why breastfed infants are particularly at risk, and what to do about it.
Efficacy and financial value of antibiotic treatment of bovine clinical mastitis during lactation — A review

Abstract The outcome of treatment of clinical mastitis in lactating cows depends on host, bacterial and managemental factors as well as on the choice of antibiotic and treatment regimen. A review of the data on the efficacy of antibiotic therapy of mastitis in terms of bacteriological cure and restoration of milk yield and quality leads to the conclusion that major improvements in bacteriological cure rate do not economically justify an increased duration of lactational therapy. The current trend for a short period of treatment with emphasis placed on clinical recovery appears justifiable on financial and welfare grounds.
The Effects of Leadership Style, Organizational Outcome, and Gender on Attributional Bias Toward Leaders

The current study examined the effects of leadership style (charismatic or autocratic) on followers' internal and external attributions for their organization's success or failure. In addition, role incongruence between the leadership style and gender was examined within the context of attributional error. Confirming the hypotheses, the results showed a three-way interaction between leadership style, gender and organizational outcome. Supporting the role incongruity theory, when there was role incongruence between the leadership style and gender (i.e., the female autocratic leader), the attributions for failure were more unfavorable toward the leader. The effect of leadership style on internal attributions for failure was mediated by likeability of the leader. Overall, the current study was the first experimental investigation of the effects of leadership style, organizational outcomes, and gender on attributional biases within a single design.
The Effect of Oven-Heat Flux on Powder-Coating Issues of Sheet Molding Compound Panels

The effects of variations in the powder bake temperature profile on the paint popping defect of sheet molding compound (SMC) panels was investigated by subjecting powder-coated panels to various heating rates using IR heaters and convective ovens, and by using a mathematical model of heat transfer and curing reaction. It was found that overheating the SMC than that required for optimum powder curing can cause high rates of outgassing of absorbed moisture and, therefore, excessive popping. It was further found that higher quantity of moisture outgassing per unit time through the molten primer layer during a fast temperature ramp causes more popping compared to a slow temperature ramp. Therefore, it is expected that any plant that is experiencing paint popping would benefit from slowing down the rate of temperature rise of the panels during the initial 5−10 min of the heating cycle.
Leukotriene and prostaglandin production in rat brain synaptosomes treated with phospholipase A2 neurotoxins and enzymes.

Abstract β-Bungarotoxin (β-BuTX) and notexin cause an irreversible blockade of neurotransmitter release through specific and potent effects at the presynaptic nerve terminal, however, the mechanism of action in uncertain. We examined the effects of β-BuTX and notexin on LT and PG production in rat cerebrocortical synaptosomes in order to determine if eicosanoid production might mediate or regulate the pharmacological actions of these phospholipase A2(PLA2) neurotoxins. The effects of the PLA2 enzymes isolated from Naja naja atra and Naja nigricollis snake venoms (which are not presynaptic selective) on LT and PG production were compared with the effects of β-BuTX and notexin. N. n. atra PLA2, β-BuTX, and notexin (all 50 nM) produced a time dependent rise in free fatty acids as measured in synaptic plasma membranes isolated from treated synaptosomes. Both the PLA2 neurotoxins and enzymes stimulated LTC4, LTB4, and PGE2 production, as measured by radioimmunoassay. In all cases, the PLA2 enzymes were more potent than the PLA2 neurotoxins. This observations correlates with their relative enzymatic potencies, as measured by free fatty acid generation. EDTA and BSA antagonized PLA2 induced LTB4 production and BSA also antagonized PLA2 induced PGE2 production. These results suggest that stimulation of eicosanoid production does not mediate the potent and specific presynaptic actions of β-BuTX and notexin.
An examination of the vibration transmissibility of the hand-arm system in three orthogonal directions

Abstract The objective of this study is to enhance the understanding of the vibration transmission in the hand-arm system in three orthogonal directions (X, Y, and Z). For the first time, the transmitted vibrations distributed on the entire hand-arm system exposed in the three orthogonal directions via a 3-D vibration test system were measured using a 3-D laser vibrometer. Seven adult male subjects participated in the experiment. This study confirms that the vibration transmissibility generally decreased with the increase in distance from the hand and it varied with the vibration direction. Specifically, to the upper arm and shoulder, only moderate vibration transmission was measured in the test frequency range (16 to 500 Hz), and virtually no transmission was measured in the frequency range higher than 50 Hz. The resonance vibration on the forearm was primarily in the range of 16–30 Hz with the peak amplitude of approximately 1.5 times of the input vibration amplitude. The major resonance on the dorsal surfaces of the hand and wrist occurred at around 30–40 Hz and, in the Y direction, with peak amplitude of more than 2.5 times of the input amplitude. At higher than 50 Hz, vibration transmission was effectively limited to the hand and fingers. A major finger resonance was observed at around 100 Hz in the X and Y directions and around 200 Hz in the Z direction. In the fingers, the resonance magnitude in the Z direction was generally the lowest, and the resonance magnitude in the Y direction was generally the highest with the resonance amplitude of 3 times the input vibration, which was similar to the transmissibility at the wrist and hand dorsum. The implications of the results are discussed. Relevance to industry Prolonged, intensive exposure to hand-transmitted vibration could result in hand-arm vibration syndrome. While the syndrome's precise mechanisms remain unclear, the characterization of the vibration transmissibility of the system in the three orthogonal dimensions performed in this study can help understand the syndrome and help develop improved frequency weightings for assessing the risk of the exposure for developing various components of the syndrome.
Parental and larval exposure to nicotine modulate spontaneous activity as well as cholinergic and GABA receptor expression in adult C. elegans.

Early nicotine exposure has been associated with many long-term consequences that include neuroanatomical alterations, as well as behavioral and cognitive deficits. To describe the effects of early nicotine exposure in Caenorhabditis elegans, the current study observed spontaneous locomotor activity (i.e., reversals) either in the presence or absence of nicotine. Expression of acr-16 (a nicotinic receptor subunit) and a β-like GABA(A) receptor subunit, gab-1, were also examined with RT-PCR. Worms were exposed to nicotine (30 μM) throughout "zygote formation" (period that includes oocyte maturation, ovulation and fertilization), from hatching to adulthood ("larval development") or across both zygote and larval development. Adult larval-exposed worms only showed an increase in spontaneous behavior when tested on nicotine (p 0.30). Larval-exposed worms also showed control levels of acr-16 nicotinic receptor expression (p>0.10) but increased gab-1 expression relative to controls (p 0.90 for each). However, expression of acr-16 and gab-1 was downregulated in zygote-exposed (p<0.01 and p<0.05, respectively) and significantly upregulated in the zygote- plus larval-exposed worms (p<0.000 for each); most surprising was the over five-fold increase in gab-1 expression. These results suggest that spontaneous motor behavior and receptor expression are differentially modulated by nicotine exposure during larval development and/or zygote formation. As well, these findings demonstrate that C. elegans, as a model system, is also sensitive to nicotine exposure during early development and provides the basis for future research to uncover specific mechanisms by which early nicotine exposure modifies neuronal signaling and alters behavior.
Role of Laparoscopic Surgery for Treatment of Early ColorectalCarcinoma

The first laparoscopic colorectal surgery was performed in 1991. Several reports have showed some advantages for the laparoscopic technique compared to open procedures, but the lack of well designed trials has produced doubts about the real advantage of laparoscopy for colorectal cancer. To date, retrospective and prospective evidence suggests that laparoscopy is as safe as conventional colorectal surgery. Two recent prospective, randomized trials have showed that the short-term outcome is not compromised after laparoscopy for colorectal cancer. Furthermore, less pain, faster recovery of respiratory parameters, and better preservation of cell-mediated immune function have been associated with the laparoscopic technique. Laparoscopic surgery for early colorectal cancer may have a role in a well selected group of patients.
Rate and Extent of Top Spoilage Losses in Horizontal Silos

Abstract Alfalfa, corn, and forage sorghum silages were stored in farm- and pilot-scale silos, and DM and OM losses and fermentation characteristics were measured at three depths within the top meter of silage. The alfalfa was unsealed or sealed immediately with .15-mm plastic sheeting. Corn and forage sorghum were unsealed, sealed immediately, sealed immediately after a topical application of a mold inhibitor, or unsealed for 7 d and then sealed after application of a mold inhibitor. All unsealed silage maintained higher temperatures within the top meter than sealed silage. Unsealed silage deteriorated completely at 25 and 0 to 33 cm in the farm- and pilot-scale silos, respectively, and farm-scale silage stored at 50 cm lost more DM and OM in unsealed than in sealed silos. Unsealed silage began to deteriorate immediately above 33 cm, and deterioration progressed to 67 cm in the silage from all three crops. Immediate sealing preserved more DM and OM after d 180 at 25 cm than delayed sealing. Recoveries of OM estimated by an equation containing silage ash content were highly correlated with actual OM recoveries in all unsealed silage. Estimated and actual recoveries were not highly correlated in sealed silage, particularly below 33 cm.
ACUTE AND CHRONIC CORONARY HEART DISEASE.

Summary The accumulated data and clinical experience of many decades seem to imply that in the clinical evaluation of coronary heart disease, it is crucially important to determine whether the disorder is in a chronic and stable phase or whether there has been an acute and spontaneous change in the coronary status. Such a change should be assumed in cases of cardiac pain of recent onset, or when there has been a change in the pattern of pre-existing angina pectoris that cannot be accounted for by such extracoronary factors as exertion, tachycardia, shock, and others. It is noted that such a change, regardless of whether it appears in the guise of exertional or nonexertional angina pectoris, or myocardial infarction, is attended in the early days and weeks by the threat of extension of the process or sudden death. It is suggested that the designation of acuteness and chronicity is essential to the terminology of various states of coronary heart disease. This is particularly the case in the syndrome of angina pectoris, in which this differentiation is critical in prognosis and therapy. The clinical picture variously referred to as “acute coronary insufficiency” or “pre-infarction angina” may appear with, or without, evidence of myocardial necrosis. Hence, the designation of these cases as acute coronary heart disease (coronary attack), with or without recognizable infarction, appears to be more accurate and may tend to clarify a field of confused and overlapping terminology. It is likely that, with refinements in diagnostic methods for detection of cardiac necrosis, an increasing number of coronary attacks without recognizable infarction will be placed in the category of small infarcts. Such a reclassification, however, will not alter the outlook and treatment of such cases, since the available evidence indicates that it is the development of an acute change in the coronary status rather than the presence of a small area of necrosis that largely determines the clinical course of the disease.
Impulse control of stochastic Navier-Stokes equations

Optimal control theory of 2uid dynamics has numerous applications such as aero= hydrodynamic control, combustion control, Tokomak magnetic fusion as well as ocean and atmospheric prediction. During the past decade several fundamental advances have been made by a number of researchers as documented in Sritharan [21,22]. In this paper we develop a new direction to this subject, namely we mathematically formulate and resolve impulse and stopping time problems. Impulse control of Navier–Stokes equations has signi7cance beyond control theory. In fact, in optimal weather prediction the task of updating the initial data optimally at strategic times can be reformulated precisely as an impulse control problem for the primitive cloud equations (which consist of the Navier–Stokes equation coupled with temperature and species evolution equations, cf. [11]), see [1,9,15]. For the study of optimal stopping problem alone, it is possible to impose regularity assumptions on the stopping cost. However, in our case, optimal stopping problems are used as intermediate steps to treat the impulse control problem through an iteration process. This dictates that we must work with stopping costs which have only continuity property. Optimal stopping and impulse control problems are very well known, particularly for di;usion processes (e.g., see the books of Bensoussan and Lions [3,4]), for degenerate
Experimental comparison of the phase-breaking lengths in weak localization and universal conductance fluctuations

The observation of quantum transport phenomena in metals is limited by the eventual loss of phase coherence of the conduction electrons on the length scale ${L}_{\ensuremath{\varphi}}.$ We address the question of whether ${L}_{\ensuremath{\varphi}}$ is the same in the context of different quantum transport phenomena. Specifically, we have measured ${L}_{\ensuremath{\varphi}}$ from two different experiments on the same sample. The experiments are magnetoresistance and $1/f$ noise versus magnetic field, and the samples are thin-Ag films in the quasi-two-dimensional regime. We determine ${L}_{\ensuremath{\varphi}}$ from fits of the magnetoresistance data to weak-localization theory (WL), and from fits of the noise versus magnetic field to universal conductance fluctuation theory (UCF). We find that the two values of ${L}_{\ensuremath{\varphi}}$ are the same at temperatures above about 10 K, but that ${L}_{\ensuremath{\varphi}}$ in the UCF experiment is shorter than that in the WL experiment at lower temperatures. This result is consistent with a recent theoretical discussion of quasielastic electron-electron scattering in disordered metals.
Effect of Method of Preparing Iso-Electric Casein on Its Electrophoretic Properties

Summary Variations in the method of preparing and purifying iso-electric casein have a significant effect on its electrophoretic properties. Peptization of casein with sodium hydroxide, even at pH 7.0, removes γ -casein in the subsequent washing. This explains the absence of γ -casein from some electrophoretic patterns reported in the literature. Beta- and γ -casein were removed by washing, only when the casein had been treated with sodium hydroxide. However, the pH of the wash water has a significant effect on the relative percentage composition of α-, β -, and γ -casein and on their electrophoretic mobilities. Standardization of the methods for preparation and purification of iso-electric casein are needed if the data reported by investigators are to be compared.
Paying attention to language

The author asserts that the practice of literacy education should be informed by linguistic theory. When teachers pay attention to language the way linguists do, they gain an understanding of the relation between children's spoken language competence and their written language acquisition.
Are SOFAR Float Trajectories Chaotic

Abstract When particle trajectories in a fluid are chaotic, the fluid is stirred efficiently, which, in turn, enhances diffusive mixing within the fluid. Regular (nonchaotic) particle trajectories on the other hand, are not associated with efficient stirring. The question of whether or not SOFAR float trajectories are chaotic is, then, central to understanding the process by which passive tracers are laterally mixed in the ocean. Two techniques commonly used to investigate the behavior of computer generated trajectories, the construction of Poincare sections and the calculation of Lyapunov exponents, cannot be applied to analyze isolated float trajectories in an unknown velocity field. Power spectra of both meridional and zonal components of float trajectories contain structure on all resolvable scales, suggesting chaotic motion. Attempts to estimate K2, a lower bound on the Kolmogorov entropy, using the Grassberger-Procaccia algorithm failed when individual trajectories were used as input. Using a multip...
An interactive session using a tool to support distributed conversations around digital video

Workshop Theme and Objectives Jordan and Henderson (1995) outline a research methodology they term interaction analysis—a powerful method for investigating human activity in which a group of researchers come together in a meeting to offer their insights on some video recorded event. Although the interaction analysis approach proved to be highly influential for ethnographers and other social scientists, it was limited by the technologies available at the time of Jordan and Henderson’s writing (VHS tapes, etc.). Reconstructing the contextually grounded insights of researchers can be an onerous task, not to mention the challenge of accommodating the schedules of several busy researchers. Fortunately, the decreasing costs and increased accessibility of digital video technologies has made it possible to support fluid conversations around a video record without the constraints of an in-person meeting. Pea, Lindgren, and Rosen (2006) present a framework for enhancing interaction analysis with internet technologies that they term computersupported collaborative video analysis (CSCVA). They also describe a software environment designed to facilitate CSCVA in the research community called DIVER (Digital Interactive Video Exploration and Reflection). The purpose of this session will be introduce to participants the theoretical issues around CSCVA and give them practice collaborating on video analysis using the DIVER platform. Session participants will have access to a large video data corpus that we have collected on families discussing the role that mathematics plays in activity at home. The goal of the session is to build fluency among participants with CSCVA tools and to have them recognize the potential for using these types of tools to improve and expand their research practices.
Nonlinear dynamics in a simple model of solid flame microstructure

Abstract We present a model of condensed phase combustion which attempts to elucidate the effects of spatially localized reaction sites on the propagation of a combustion wave. Heat transfer is assumed to be uniform but exothermic reactions are allowed to occur only at evenly distributed locations, that we refer to as reactant particles. Thus, combustion wave propagation manifests itself as a process of sequential ignition and burning of particles. Green’s functions are used to show that “steady” wave speed is related to particle ignition temperature, particle geometry and the ratio of heat diffusion to reaction times through a single transcendental equation. Furthermore, for the one-dimensional case, the dynamics of this system can be related to a history dependent implicit map f → : R ∞ → R ∞ which determines time to the next ignition. Iteration of this map demonstrates that average wave speed undergoes a period doubling bifurcation to chaos and subsequent extinction. A linear stability analysis of this map is performed to determine the stability boundaries for period 2n orbits. Additionally, temperature profiles are shown to be in qualitative agreement with experiments which describe a transition from the so-called quasi-homogeneous to relay-race regimes.
Why Isn't the Whole World Developed? A Traditional View

Why isn't the whole world developed? This vital question posed by Richard Easterlin is addressed in Gregory Clark's much-noted article in this JOURNAL.1 Clark iconoclastically claims that the main difference between developed and less developed countries is the comparative efficiency of labor, which in turn is explicable in terms of local culture and environment. He skillfully illustrates his thesis with evidence from the world cotton-textile industry in the early twentieth century. This evidence also leads him to question the overweening importance typically ascribed to technological progress in explaining high incomes. I disagree with some of Clark's points, although I would neither claim that the efficiency of labor is immaterial to income and productivity differences among countries, nor that culture and environment should be disregarded. But in allocating scholarly resources choice is unavoidable. So there is good reason to appraise his contribution and proposed research agenda.
On the matrix Riccati equation

The matrix Riccati equation and its relation to optimization, sensitivity, and stability problems in linear systems is noted. Explicit solutions are summarized for several particular cases with emphasis on direct and unified proofs. In the stationary case, a direct proof is given for the well-known relation between solutions of the Riccati differential and algebraic equations.
Sodium-dependent extracellular accessibility of Lys-84 in the sodium/dicarboxylate cotransporter.

The Na+/dicarboxylate cotransporter transports Na+ with citric acid cycle intermediates such as succinate and citrate. The present study focuses on transmembrane helix 3, which is highly conserved among the members of the SLC13 family. Fifteen amino acids in the extracellular half of transmembrane helix (amino acids 98–112) as well as Lys-84, previously shown to affect substrate affinity, were mutated individually to cysteine and expressed in the human retinal pigment epithelial cell line. Transport specificity ratio analysis shows that determinants for distinguishing succinate and citrate are found at amino acids Lys-84, Glu-101, Trp-103, His-106, and Leu-111. All of the mutants were tested for sensitivity to the membrane-impermeant cysteine-specific reagent (2-sulfonatoethyl) methanethiosulfonate (MTSES), but only K84C was sensitive to MTSES inhibition. The sensitivity of K84C to MTSES was greatest in the presence of sodium, and the inhibition could be prevented by addition of substrate or replacement of sodium, indicating that the accessibility of Lys-84 changes with conformational state. The substrate protection of MTSES inhibition of K84C appears to occur early in the transport cycle, before the large-scale conformational change associated with translocation of substrate. The results point to a new location for Lys-84 within the substrate access pore of the Na+/dicarboxylate cotransporter, either in a transmembrane helix or a reentrant loop facing a water-filled pore.
Academic achievement and acceptance rates of underrepresented-minority applicants to medical school.

Abstract While the participation of minority groups underrepresented in medicine has increased from 3% of first-year enrollment in 1968-69 to 11% in 1992, many have been concerned that the percentage of underrepresented-minority applicants accepted is smaller than that of other applicants. To investigate the relationship of acceptance rates and measures of academic achievement, historical data from 1978-79 through 1991-92 on applicant characteristics maintained by the Association of American Medical Colleges were used to develop statistics on acceptance rates for underrepresented minorities and for other applicants, by each applicant's mean score on the MCAT (Medical College Admission Test) and undergraduate science grade point average. Those statistics were then related to trends in applicant numbers. Results show that acceptance rates for both underrepresented minorities and others increased as the numbers of applications from both groups declined, then decreased as applications again rose. When underrepresented-minority applicants were compared with other applicants within the same ranges of grades and MCAT scores, underrepresented-minority applicants were accepted at substantially higher rates in every stratum. Thus, medical schools generally are acting affirmatively in selecting applicants from underrepresented-minority groups.
Effects of oestrogen upon tensile properties of healing fractured avian bone

The present work considers some of the effects of oestrogen treatment on the biomechanical properties of long bones during the process of osteosynthesis. The influence of the steroid was assessed by determining the tensile strength properties of treated and untreated healing fractured ossa radii. The ultimate tensile strength and modulus of elasticity were determined at one and two week post-fracture induction. In general, oestrogen treatment decelerated healing process of long bones. This was indicated by a significantly reduced ultimate tensile callus strength of oestrogen-treated birds over a two week period post-fracture induction. The same group also exhibited a significant increase in callus cross-sectional area while the elastic moduli of their bones were not significantly different at either one or two weeks post-fracture induction.
Intimate Partner Violence in a Statewide Couple and Relationship Education Initiative

As couple and relationship education (CRE) has become an increasingly common intervention, issues surrounding the awareness, prevention, and treatment of violence have been raised. Concerns include the level of risk among participants, appropriate training for educators, and the extent to which CRE increases or mitigates risks for intimate partner violence (IPV). This study reports the level of risk among CRE participants and explores the associated experiences of county Cooperative Extension agents who served as the CRE educators in Utah. The educators presumed those interested in CRE would not be experiencing IPV. However, 10% of CRE participants indicated moderate-to-severe risk, and an additional 29% indicated likelihood of at least mild violence. Implications include the need for CRE initiatives to (a) take the possibility of IPV seriously, (b) train educators to identify and handle diverse types of IPV, and (c) monitor the implementation of IPV protocols.
Copper-containing oxidases.

Major advances have been made during 1997 and 1998 toward understanding the structure/function relationships of the active sites in copper-containing oxidases. Central to this progress has been the elucidation of crystal structures for many of these enzymes. For example, studies of the mechanisms of biogenesis and/or catalysis of amine oxidase and galactose oxidase have been both stimulated and directed by the availability of stuctures for these proteins. Similarly, it is anticipated that the recently published crystal structures of peptidylglycine oc-hydroxylating monooxygenase and laccase will contribute greatly toward understanding the roles of copper in these two proteins.