cssi/SciSciGPT-SciSciNet huggingface dataset:
Recent trends in vegetation dynamics in the African Sahel and their relationship to climate

Contrary to assertions of widespread irreversible desertification in the African Sahel, a recent increase in seasonal greenness over large areas of the Sahel has been observed, which has been interpreted as a recovery from the great Sahelian droughts. This research investigates temporal and spatial patterns of vegetation greenness and rainfall variability in the African Sahel and their interrelationships based on analyses of Normalized Difference Vegetation Index (NDVI) time series for the period 1982–2003 and gridded satellite rainfall estimates. While rainfall emerges as the dominant causative factor for the increase in vegetation greenness, there is evidence of another causative factor, hypothetically a human-induced change superimposed on the climate trend. r 2005 Elsevier Ltd. All rights reserved.
Conversion of covalently mercurated nucleic acids to tritiated and halogenated derivatives.

Mercurated nucleic acids are converted to the corresponding tritiated, brominated, and iodinated derivatives by treatment with sodium borotritiide, N-bromosuccinimide, and elemental iodine, respectively. All three reactions occur under mild conditions in neutral aqueous solutions. Mercury-halogen conversions are essentially quantitative at both the mono- and polynucleotide levels. Tritiation reactions also proceed efficiently with mononucleotides, although polymers undergo incomplete demercuration. In spite of the latter limitation , these reactions provide novel and efficient synthetic routes to radiolabeled nucleic acid derivatives.
Effects of zinc chloride on the cleavage of ether structures present in coal

Abstract A number of compounds which model the ether structures found in coal were subjected to reaction in the presence of ZnCl2. Both cyclic and non-cyclic ethers reacted, provided that at least one methylene group was present adjacent to the ether oxygen atom. Complete elimination of oxygen to form water was achieved with dibenzyl and cycloaliphatic ethers, but oxygen bonded directly to a phenyl or naphthyl group was converted to an unreactive phenolic hydroxyl group.
Prediction of Equilibrium Surface Tension and Surface Adsorption of Aqueous Surfactant Mixtures Containing Ionic Surfactants

We report results of a theoretical study of the adsorption of mixtures of ionic and nonionic surfactants at the aqueous solution−air interface. A surface equation of state is developed by treating the adsorbed surfactant molecules as a two-dimensional gaslike monolayer consisting of hard disks interacting through attractive van der Waals interactions and repulsive electrostatic interactions. The hard-disk areas are calculated using known bond lengths and angles in the case of surfactants having compact hydrophilic heads and a Monte Carlo simulation approach in the case of surfactants having flexible, polymer-like hydrophilic heads. Attractive van der Waals interactions between the surfactant hydrocarbon tails are treated as a purturbation to the hard-disk repulsions using an expansion in surfactant surface concentration truncated at second order. The corresponding second-order virial coefficients are calculated using detailed molecular information about the surfactant species present in the monolayer. Ele...
FORMATION OF C60 ADDUCTS WITH TWO DIFFERENT ALKYL GROUPS VIA COMBINATION OF ELECTRON TRANSFER AND SN2 REACTIONS

The formation of organofullerenes of the type R2C60 and R(R‘)C60 from C602- and alkyl halides (RX or R‘X) in benzonitrile was mechanistically investigated for 15 different alkyl halides which vary in electrophilicity and electron acceptor ability. The first step in the reaction leads to RC60- via an electron-transfer mechanism, followed by formation of R2C60 or R(R‘)C60 via an SN2 mechanism. Evidence of the mechanism comes from comparison of rate constants for the stepwise addition of two R groups to C602- with rate constants for the genuine electron transfer and SN2 reactions. The formation of t-BuC60- and PhCH2C60- after the first R group addition was confirmed by electrospray ionization mass spectroscopy. The t-BuC60- derivative will not react further with excess t-BuI, but this is not the case for the less sterically hindered PhCH2Br, which adds to t-BuC60- in benzonitrile to give t-Bu(PhCH2)C60. A protonation of t-BuC60- with trifluoroacetic acid can also occur to give 1,4-t-Bu(H)C60, which rearrange...
A reproducible method for preparation and operation of microwave excited electrodeless discharge lamps: SIMPLEX optimization of experimental factors for a cadmium lamp☆

Abstract By means of a SIMPLEX optimization procedure, cadmium electrodeless discharge lamps (EDLs) operated at microwave frequencies (2450 MHz) were prepared and optimized with respect to: weight of cadmium, W1 = 680–750 μg; time interval of the EDL blank under vacuum after water removal, t1 = 0–1000 s; pressure of argon gas (under microwave excitation) during preparation, A1 = 1–2.5 torr; microwave power for discharge during preparation, P1 = 90–10O W; time interval for microwave discharge during preparation, t2 = 20–28 s; time for EDL to cool before evacuation, t3 = 240 s; time under vacuum after cooling period, t4 = 0–500 s; pressure of argon to fill lamp, A2 = 6–9 torr; microwave power for operation of EDL, P2 = 55–65 W; and operating temperature of EDL, T = 290–330°C. Under the above conditions, EDLs were prepared reproducibly (atomic fluorescence detection limits were all within a factor of 3 or less). The resulting EDLs were consistently as good as or better than the best EDLs prepared in the past by the laboratory. Throughout the SIMPLEX optimization procedure, no EDL failed; all EDLs behaved as would be predicted by the preparation procedure.
Interleukin-1 (IL-1) Receptor Type I Mediates Anorexia but not Adipsia Induced by Centrally Administered IL-1β

IL-1beta induces anorexia and adipsia. Here, we report that intracerebroventricular (ICV) pretreatment with an antisense (but not sense) phosphothio-oligodeoxynucleotide to the IL-1 receptor type I (IL-1RI, 1.28 microg or 239 pmol twice daily for 3.5 days before IL-1beta plus antisense) inhibits the anorexia, but not the adipsia induced by the ICV administration of 2.0 ng IL-1beta/rat (a dose that yields estimated pathophysiological concentrations in the cerebrospinal fluid). The mean 2 h food intake decrease in response to IL-1beta was 5.6% (n = 10) in the antisense- and 43% in the sense (n = 9)-treated groups; the mean 2 h water intake decrease was 40% in the antisense- and 39% in the sense-treated groups. The intraperitoneal administration of IL-1RI antisense, in doses equivalent to those administered centrally, had no effect on the anorexic effect induced by ICV administered IL-1beta; this indicates a direct action in the central nervous system. The results suggest that: i) IL-1RI is involved in the short-term anorexigenic, but not the adipsogenic effect induced by centrally administered IL-1beta; and ii) the approach presented using antisense strategies is applicable to study the molecular basis of IL-1 mediated behaviors.
Student and faculty perceptions of lecture recording in a doctor of pharmacy curriculum.

Objective. To describe students’ and faculty members’ perceptions of the impact of lecture recording in a doctor of pharmacy (PharmD) curriculum.Methods. Second- and third-year pharmacy students and faculty members completed an anonymous survey instrument regarding their perceptions of lecture recording with 2 classroom lecture capture software programs, Camtasia Studio and Wimba Classroom.Results. Most students (82%) responded that Camtasia was very helpful and almost half (49%) responded that Wimba Classroom was helpful (p<0.001). Forty-six percent of the students reported being more likely to miss a class that was recorded; however, few students (10%) reported using recordings as a substitute for attending class. The most common concern of faculty members was decreased student attendance (27%).Conclusion. Pharmacy students consider lecture recordings beneficial, and they use the recordings primarily to review the lecture. While faculty members reported concerns with decreased attendance, few students r...
A product-line requirements approach to safe reuse in multi-agent systems

The dynamic nature of highly autonomous agents within distributed systems is difficult to specify with existing requirements techniques. However, capturing the possibly shifting configurations of agents in the requirements specification is essential for safe reuse of agents. The contribution of this work is an extensible agent-oriented requirements specification template for distributed systems that supports safe reuse. We make two basic claims for this idea. First, by adopting a product-line-like approach, it exploits component reuse during system evolution. Second, the template allows ready integration with an existing tool-supported, safety analysis technique sensitive to dynamic variations within the components (i.e., agents) of a system. To illustrate these claims, we apply the requirements specification template and safety analysis to a real-world context-aware, distributed satellite system.
Interactions between chemical and thermal cutaneous stimuli: inhibition (counterirritation) and integration.

Methyl salicylate, a commonly used chemical counterirritant, was applied topically to the forearm to determine whether a nonpainful chemical irritation could inhibit the perception of another (weaker) chemical irritation. In the first experiment, sensations of irritation (burning and stinging) produced by a 10% solution of methyl salicylate were significantly attenuated when a 15% solution of the same chemical was applied to the opposite forearm. In the second experiment, neither the perception of warmth nor the heat pain threshold was affected by application of 10% or 15% methyl salicylate to a site 10 cm from the thermal stimulus. Inhibition did, however, occur in the opposite direction: Chemical irritation was reduced after the thermal stimulus reached a painful level. In the third experiment, a 15% solution of methyl salicylate was applied immediately adjacent to the thermal stimulus, with the result that ratings of warmth intensity increased rather than decreased, and perceived irritation was again a...
Tuskegee Bioethics Center 10th anniversary presentation: "Commemorating 10 years: ethical perspectives on origin and destiny".

More than 70 years have passed since the beginning of the Public Health Service syphilis study in Tuskegee, Alabama, and it has been over a decade since President Bill Clinton formally apologized for it and held a ceremony for the Tuskegee study partici- pants. The official launching of the Tuskegee University National Center for Bioethics in Research and Health Care took place two years after President Clinton's apology. How might we fittingly discuss the Center's 10th Anniversary and the topic Commemorating 10 Years: Ethical Perspectives on Origin and Destiny? Over a decade ago, a series of writers, many of them African Americans, wrote a text entitled African-American Perspectives on Biomedical Ethics; their text was partly responsible for a prolonged reflection by others to produce a subsequent work, African American Bioethics: Culture, Race and Identity. What is the relationship between the discipline of bioethics and African American culture? This and related questions are explored in this commentary. t has been more than 70 years since the beginning of the Public Health Service syphilis study in Tuskegee, Alabama, and over a decade since President Bill Clinton formally apologized for it and held a ceremony for the Tuskegee study participants. The official launching of the Tuskegee University National Center for Bioethics in Research and Health Care took place two years after President Clinton's apology with $200,000 in seed money from the federal government (built on with over $20 million in grants and pledges since). How might we fittingly discuss Tuskegee Bioethics Center 10th Anniversary and the topic, Commemorating 10 Years: Ethical Perspectives on Origin and Destiny? More than a decade ago, a series of writers, many of them African Americans, wrote a text entitled African-American Perspectives on Biomedical Ethics; 1 their text was partly responsible for a prolonged reflection by others to produce a subsequent work, African American Bioethics: Culture, Race and Identity. 2 The notion of an African American bioethics is perplexing, and some might argue there is no such thing. Let us try and reframe the issue: What is the relationship between
Plain talk about creating a gifted‐friendly classroom

This article discusses optimum conditions for gifted students in regular classrooms, including the advantages of cluster grouping and curriculum compacting. The need for providing psychological safety is also discussed, as well as the importance of positive teacher attitudes toward gifted students. Specific cognitive and affective classroom strategies are recommended and additional resources are suggested.
The response of clinical balanitis xerotica obliterans to the application of topical steroid-based creams

Objective: The aim of this study was to assess the effectiveness of using topical steroid-based creams in the management of clinically diagnosed balanitis xerotica obliterans (BXO) in boys. Methods: The response in 56 boys to locally applied steroid-based creams was studied retrospectively. All had been referred by their general practitioners with symptoms of penile pathology and then subsequently had a clinical diagnosis of BXO made. The boys were initially assessed after 3 months of treatment and then at various intervals depending on their response. Results: The mean age at presentation of the boys was 8.9 (4 to 15) years. After the initial 3-month assessment, 10 (17.9%) boys had complete resolution. When the treatment period was prolonged by an average of 14 months, the total number of boys showing resolution increased to 17 (30.4%). All boys showing resolution had clinically mild BXO limited to the prepuce only. Those patients with established scar formation on the foreskin showed no significant improvement. Conclusions: Topical steroids seem to offer a reliable option only in the management of mild BXO limited to the prepuce in boys with minimal scar formation. Steroid-based creams can be offered to such patients provided they and their families are realistic as to the likelihood of success. This treatment is ineffective in the face of established scarring.
Comparison of the haplotypes of the major histocompatibility complex in the rat. V. A serological, genetic and numerical study of the RT1.A region antigens.

Summary The classification of the RT1.A phenotypes of a large number of inbred and congenic strains of rats, including those prototypic for all of the known RT1.A phenotypes, was done by examining the reactivity of a variety of unabsorbed antisera with cells of the different strains. The data were analysed by the techniques of numerical taxonomy without reference to the previous classification by the classical serological methods. The most effective way of analysing the data was the use of the Jaccard correlation coefficient and the average linkage method of statistical analysis. Four conclusions were drawn from this study. First, the RT2 antigens must be matched in the donor and recipient pair used to raise the anti-RT1 (MHC) antiserum or spurious typing results can occur due to the presence of anti-RT2 antibodies. Second, using anti-RT1 antisera raised in RT2 compatible pairs of rats, the classification of inbred and congenic strains into the RT1.A phenotypes on the basis of classical serological studies was confirmed. Third, two groups of closely related RT1.Ac phenytopes were found (a, f, d and b, m). Fourth, the AUG and PVG strains, both of which carry the the RT1.Ac phenotype, are quite distantly related on the basis of this taxonomic analysis and the RTl.Ag and RT1.An phenotypes are the most distantly related compared to all of the other rat strains and to each other. These data provide further evidence that the RT1 polymorphism of the rat is very limited, especially in respect of man and mouse.
Differential promoter usage of mouse μ-opioid receptor gene during development

Previously, we demonstrated that mouse mu-opioid receptor (MOR) gene expression is regulated by both distal and proximal promoters, with the latter playing a major role in controlling MOR transcription in the adult mouse brain. Here, we report studies of the relative usages of the mouse MOR dual promoters during murine development. We used the reverse transcription-polymerase chain reaction (RT-PCR) method, which gave results similar to those using binding assays or in situ hybridization. However, due to the greater sensitivity of RT-PCR method, we were able to detect the emergence of MOR as early as at embryonic day 8.5 (E8.5). We found that both proximal and distal promoters were active at E8.5. The proximal promoter initiated approximately two-thirds of total MOR transcripts at E8.5, with the distal promoter directing transcription of the remaining one-third. This is the greatest relative contribution of the distal promoter to MOR transcription we have observed during any time in development. Thereafter, the percentage of transcripts directed by the distal promoter gradually declined, and remained at a low but detectable level (approximately 5% of total MOR transcripts) throughout development and adulthood. Conversely, a progressive increase of the contribution of the proximal promoter to MOR transcription was observed during development, reaching its maximum in the adult. In summary, our results demonstrated the pivotal role of the proximal promoter in directing MOR transcription during murine development.
A method for estimating the solids circulation rate in a closed-loop circulating fluidized bed

Abstract We propose a simple method for accurately estimating the solids circulation rate in a closed-loop liquid–solid circulating fluidized bed. The technique is based on the use of radioactive isotopes for estimating the solids velocity and volume fraction distribution in a chosen section of the circulating fluidized bed loop. The method is demonstrated for a liquid–solid circulating fluidized bed, and is readily applicable in other systems such as gas–solids circulating fluidized beds or closed-loop pneumatic and hydraulic transport lines. With minor modifications, the method may be used for industrial systems as well.
Contextual emotion-regulation therapy for childhood depression: description and pilot testing of a new intervention.

ABSTRACT Objective: To pilot test the acceptability and efficacy of contextual emotion-regulation therapy (CERT), a new, developmentally appropriate intervention for childhood depression, which focuses on the self-regulation of dysphoria. Method: Two samples of convenience ( n = 29, n = 2) served to verify some CERT constructs; it was then operationalized in a treatment manual. To pilot test CERT, 20 children (ages 7-12; 35% girls) with DSM dysthymic disorder (mean duration 24.4 months) entered an open, 30-session, 10-month, 4-phase trial, with 6- and 12-month follow-up. Assessments included independent clinical evaluations and self-rated questionnaires. Results: Fifteen children completed theraphy, four were administratively terminated and one dropped out. Completers did not clinically differ from the rest, but they were more likely to have better educated and less depressed mothers and intact families. At the end of treatment, 53% of the completers had full and 13% partial remission of dysthymia (remission from superimposed major depression was 80%). By 6- and 12-month follow-up, 79% and 92% had full remission of dysthymia ( p p Conclusions: CERT enables clinicians to "match" the intervention to children's emotion regulatory needs and symptoms and was readily accepted by families. The promising results suggest the need for a randomized trial.
Total Variation Regularized Deconvolution of Extended Depth of Field Microscope Images

Total variation regularized deconvolution provides a highly accurate reconstruction of extended depth of field microscopy images. Several versions of the deconvolution problem, tailored for specific noise distributions, are presented. Results are compared with linear filters.
The field-assisted penetration of a silver film into glass

Abstract The application of a DC field to a sodium-containing glass plate coated with a silver film causes Ag + and Na + ions to move toward the cathode, retaining the transparency of the glass. Characteristics of the process have been experimentally studied from various viewpoints: current and voltage versus time, fluorescence generation/annihilation, refractive index increase, spectral reflectivity characteristics, internal strain generation, volume increase, the weight of penetrated silver versus transported electric charge and concentration profiles. The dynamics of the process have been shown to be approximately linear. The linearity is considered to come from the following: (1) the resistance of a Ag-penetrated layer is much smaller than that of the whole of a glass plate and (2) Na + ions are not piled up in the vicinity of the cathode-side surface.
Boundary Integrals: An Efficient Method For Modeling Seismic Wave Propagation In 3-D

Seismic modeling in 3-D, using differential methods such as finite difference (FD) or finite element (FE), is very computer intensive, albeit quite general. When a heterogeneous medium consists of regions having piecewise constant properties, integral methods provide an skernative. Boundary Integral Equations (BIE) yield an exact formulation of the problem, but may still be uneconomical for relatively large problems. Boundary Integrals (BI) are approximate formulations which depend on one-way wave propagation and provide the most efficient wave-theoretic modeling capability. The secalled ‘Kirchhoff Modeling’ is but one of many BI methods. Illustrative examples will show the extent of the validity of these approximate methods.
Binding of chloroplast coupling factor 1 deficient in the δ subunit to thylakoid membranes

The ability of chloroplast coupling factor 1 (CF 1 ) deficient in the δ subunit (CF 1 (−δ)) to bind to thylakoids from which CF 1 has been removed was clarified. CF 1 (−δ) failsto restore ATP synthesis to CF 1 -depleted membranes. Reconstitution of photophosphorylation by CF 1 was not inhibited by the presence of prebound CF 1 (−δ) or free CF 1 (−δ) in the reconstitution mixture. The amount of bound CF 1 (−δ) displaced by a large excess of CF 1 was very small and CF 1 (−δ) in solution displaced nearly the same amount of bound CF 1 . On the other hand, CF 1 (−δ) still bound to the membranes, even after both the CF 1 (−δ) and NaBr particle preparations were treated with anti-δ serum. The binding of CF 1 to CF 1 -depleted membranes was inhibited by the presence of prebound CF 1 (−δ) or free CF 1 (−δ) in the reconstitution mixtures. The binding of both CF 1 and CF 1 (−δ) was inhibited by chymotrypsin treatment of the enzymes, and the dithiothreitol-activated Ca 2+ -ATPase activities of both CF 1 and CF 1 (−δ) were inhibited by binding. These results indicate that although CF 1 (−δ) fails to bind to the sites which are functional for ATP synthesis, it is able to bind specifically to CF 1 -depleted membranes. This suggests that only part of CF 0 is functional for ATP synthesis. For unknown reasons, CF 1 appears to bind to both functional and damaged CF 0 , whereas CF 1 (−δ) binds preferentially to the altered CF 0 .
A new murine tumor model for studying HLA-A2-restricted anti-tumor immunity

Abstract HLA-A2/K b transgenic mice have been powerful tools for studying HLA-A2-restricted anti-tumor immunity. Two tumor lines were established from an aged HLA-A2/K b transgenic mouse that developed spontaneous tumors in the right limb and lung. Histopathologic analysis of the tumor was consistent with an osteosarcoma that had metastasized to the lung. The cells from the primary tumor and the lung metastasis were adapted to culture and are designated Ag201P and Ag201M, respectively. Both Ag201P and Ag201M induced tumors in mice, indicating that the established cell lines are tumorigenic. Both tumor lines expressed HLA-A2/K b as assessed by RT-PCR and immunofluorescence analysis. Furthermore, the HLA-A2/K b molecules were functional on both tumor lines as demonstrated by their ability to present exogenously loaded HLA-A2-restricted peptides to human HLA-A2-restricted T cells. More importantly, endogenously expressed HLA-A2-restricted epitopes were processed and presented in the context of HLA-A2/K b in Ag201P and Ag201M cells to human HLA-A2-restricted T cells. Thus, Ag201P and Ag201M are two new murine tumor lines that express functional HLA-A2/K b , and represent potentially invaluable tools to study HLA-A2-restricted anti-tumor immunity in mice.
Pelvic stress injuries: the relationship between osteitis pubis (symphysis pubis stress injury) and sacroiliac abnormalities in athletes

Objective. To demonstrate with radiographic imaging the association between pubic stress injury and sacroiliac abnormalities in athletes. Design and patients. Eleven athletes (9 men and 2 women), comprising seven male long-distance runners, one male soccer player, one male and two female basketball players, were imaged with plain films for complaints of pubic symphysis pain, sciatica, groin pain, or a combination of these complaints. In addition to the plain films, four patients were imaged with CT, two patients had MR imaging, and a bone scan was performed in three patients. Anteroposterior plain films of the pelvis of 20 patients without back pain or pubic pain were evaluated for comparison as a control group (ages 18–72 years, average 49 years; 11 women and 9 men). Results. All athletes showed plain film evidence of either sclerosis, erosions or offset at the pubic symphysis. Four had avulsion of cortical bone at the site of insertion of the gracilis tendon. Four patients demonstrated sacroiliac joint abnormalities on plain films consisting of sclerosis, erosions and osteophytes, and in one of these athletes, bilateral sacroiliac changes are present. Two patients with normal sacroiliac joints on plain films had a bone scan showing increased radionuclide uptake bilaterally at the sacroiliac joints. One patient with both plain film and CT evidence of sacroiliac abnormalities had an MR examination showing abnormal signal at both sacroiliac joints and at the pubic symphysis. A sacral stress fracture was found on CT in one patient with complaints of sciatica. In the control group, six patients, all over the age of 55 years, had mild sclerosis of the symphysis, but no plain film evidence of sacroiliac abnormalities. Conclusion. We have found a group of athletes in whom stress injuries to the pubic symphysis are associated with changes in the sacroiliac joint as demonstrated by degenerative changes or in the sacrum as manifested as a sacral stress fracture. These findings are probably due to abnormal stresses across the pelvic ring structure that lead to a second abnormality in the pelvic ring. The abnormality in the sacrum is not always well seen with conventional imaging. Recognition of the association of stress injury of the symphysis with back pain is important in that it can help avoid inappropriate studies and diagnostic confusion.
An electron temperature distribution derived from optical and radio measurements of HII regions

Radio measurements of the electron temperature ofHii regions are obtained from the ratio of the brightness temperature of a hydrogen recombination line to that of the adjacent continuum, while optical measurements are obtained from the ratio of [Oiii] forbidden-line intensities. The radio and optical measurements made under the assumption of an isothermalHii region,TR andTopt respectively, are combined to derive a temperature distribution for an entire nebula. A sphericalHii region in local thermodynamic equilibrium with constant density which is optically thin in both the line and the continuum is used as a model. Assuming linear temperature gradients withTR=6000K andTopt=10000K, it is found thatT=12000K (1–0.74r/R), wherer is the distance from the center andR is the radius of the nebula.
Scour and fill in steep, sand-bed ephemeral streams

The traditional idea that entire long reaches of alluvial stream channels in semiarid regions are scoured at high flood discharges and subsequently filled in the waning flood phase (mean-bed scour and fill) can be challenged. The alternative concept that mean-bed elevation varies but little during a flood and that both scour and fill occur concurrently at different migrating loci within a reach (local scour and fill) is also consistent with published field data. Field and laboratory investigations reported herein suggest that mean-bed scour and fill in a straight uniform channel is minor compared to local scour and fill caused by bedform migration and, furthermore, that maximum local scour and fill may occur during the waning flood phase in some instances. The field experiment, utilizing a rectilinear array of maximum-scour indicators (scour-cords), produced data for contoured plots of maximum scour and fill in an ephemeral stream bed during two floods. In the first flood, 24 cm of scour and fill was measured for a bankfull flow depth of 23 cm. In the second, maximum scour and fill was at least 66 cm for a bankfull flow depth of 34 cm. Estimates of antidune amplitudes for the two floods, based on theoretical models and laboratory and field observations, are 27 to 61 cm and 44 to 92 cm, respectively. This indicates that all scour and fill measured by the scour-cord array could have been caused by antidune migration. Laboratory experiments were conducted in an 18-m long non-recirculating flume with automated controls for rates of sediment and water input. A series of experiments in a 26.7-cm-wide sand-bed channel with rigid walls, at grade for a simulated flood patterned after those typical of ephemeral streams, showed that mean-bed scour and fill was less than 3% of local scour and fill. For these experiments, mean sand size was 0.3 mm, channel slope was 0.009, maximum water depth was 40 mm, maximum local scour and fill was 22 mm, and maximum mean-bed scour and fill was 0.6 mm. Maximum mean-bed elevation variation was thus only two sand-grain diameters. Maximum local scour and fill took place near the end of the simulated floods, when bed-form amplitudes were the greatest. Antidune amplitudes calculated for flows in the Arroyo de los Frijoles, New Mexico, are larger than published values of scour and fill for unit discharges greater than 0.5 m 3 /m · s (5 cfs/ft). Below that threshold discharge, the antidunes that formed at maximum flood discharge are smaller than the dunes that probably form during the waning flood, and calculated antidune amplitudes are less than reported scour and fill.
Transplanted neurons alter the course of neurodegenerative disease in Lurcher mutant mice.

Embryonic cerebellar, neocortical, and striatal tissues derived from NSE-LacZ transgenic mice were transplanted into the right cerebellar hemisphere of 8- to 10-day-old Lurcher or wild-type mice. Host mice survived for 30-90 days and the transplanted tissue was examined by light microscopy using Nissl staining, X-gal histochemistry, and immunohistochemistry for calcium binding protein and glutamic acid decarboxylase. Transplantation of cerebellar tissue, but not neocortical or striatal progenitors, resulted in robust infiltration of the lurcher mutant host cerebellar cortex by transgenic Purkinje neurons. Deep to the infiltrated molecular layer, the host granular layer was thicker and denser than the mutant granular layer, but transgenic cells did not contribute to the spared granular layer. The host inferior olivary complex consistently exhibited a noticeable bilateral asymmetry in Nissl-stained sections. A quantitative analysis of the olivary complex was performed in 10 90-day-old host mice. The results indicate that the left inferior olivary complex of 90-day-old host mice contained more neurons than the right inferior olive of the host mice and contained more neurons than was observed in 90-day-old Lurcher control mice. Analysis by olivary subdivision indicates that increased neuron numbers were present in all subdivisions of the host left inferior olive. These studies confirm the specific attractive effect of the mutant cerebellar cortex on transplanted Purkinje neuron progenitors and indicate that neural transplants may survive the neurodegenerative period to interact with developing host neural systems. The unilateral rescue of Lurcher inferior olivary neurons in cerebellar transplant hosts indicates that transplanted neurons may interact with diseased host neural circuits to reduce transneuronal degeneration in the course of a neurodegenerative disease.
Necessary and sufficient conditions on Q ( = ) C ( l ( + ) PC ) –1 ) for stabilization of the linear feedback system S ( P,C )

Abstract We find the following necessary and sufficient conditions for Q (:= C ( I + PC ) −1 ) to H -stabilize the standard linear time-invariant unity feedback system S ( P , C ) where P has the l.c.f. ( D pl , N pl ) and the r.c.f. ( N pr , D pr ); and H is a principal ideal domain. (i) Q must have elements in H (ii) (resp. (iii)) Q must factorize in H with D pr , (resp. D pl ) as a left (resp. right) factor and (iv) ( I – QP ) must factor in H with D pr , as a left factor.
Effect of Flow Pulsations on the Cooling Effectiveness of an Impinging Jet

An experimental investigation has been performed to study the effect of flow pulsations on local, time-averaged convective heat transfer to an impinging water jet. Sinusoidal and square-pulse waveforms were considered. For the square waveform, the flow was completely halted for a portion of the pulsation cycle. Hot-film anemometry was used to characterize both the steady and the pulsating flows with regard to turbulence level and the spatial uniformity in the velocity profile across the nozzle width in order to assess separately the influence of flow pulsation on convective heat transfer. Pulse magnitude, which was defined as the ratio of the mean-to-peak velocity change to the mean flow velocity, was varied from 0.5 to 100 percent
QCD MINIJET CROSS-SECTIONS

We calculate the lowest-order QCD jet cross section for a variety of different sets of structure functions, QCD scales, and parton minimum transverse momentum {ital p}{sub {ital T}}{sup min}. We compare our theoretical results with the experimental data for the jet differential and total cross sections including the minijet regime in order to study the correlations between the various parameters. We find that for a constant {ital K} factor the choice of scale {ital Q}{sup 2}=p{sub T}{sup 2} provides the best representation of the experimental data. With a {ital K} factor of order 2, a theoretical cutoff of {ital p}{sub {ital T}}{sup min}{similar to}3 GeV seems to describe the observed total minijet cross section with {ital E}{sub {ital T}}{sup jet} ({ital E}{sub {ital T}}{sup raw}){ge}5 GeV. We extrapolate our results to yield predictions for the expected minijet cross section at the Fermilab Tevatron Collider which should have some resolving power to distinguish the different sets of structure functions and choices of scale.
Head-and-face shape variations of U.S. civilian workers.

The objective of this study was to quantify head-and-face shape variations of U.S. civilian workers using modern methods of shape analysis. The purpose of this study was based on previously highlighted changes in U.S. civilian worker head-and-face shape over the last few decades – touting the need for new and better fitting respirators – as well as the study's usefulness in designing more effective personal protective equipment (PPE) – specifically in the field of respirator design. The raw scan three-dimensional (3D) data for 1169 subjects were parameterized using geometry processing techniques. This process allowed the individual scans to be put in correspondence with each other in such a way that statistical shape analysis could be performed on a dense set of 3D points. This process also cleaned up the original scan data such that the noise was reduced and holes were filled in. The next step, statistical analysis of the variability of the head-and-face shape in the 3D database, was conducted using Principal Component Analysis (PCA) techniques. Through these analyses, it was shown that the space of the head-and-face shape was spanned by a small number of basis vectors. Less than 50 components explained more than 90% of the variability. Furthermore, the main mode of variations could be visualized through animating the shape changes along the PCA axes with computer software in executable form for Windows XP. The results from this study in turn could feed back into respirator design to achieve safer, more efficient product style and sizing. Future study is needed to determine the overall utility of the point cloud-based approach for the quantification of facial morphology variation and its relationship to respirator performance.
The effect of hypovitaminosis A on bone healing and endochondral ossification in rats.

Abstract The present study of bone behavior in vitamin A deficiency is based upon histologic and roentgenographic examination of the healing tooth sockets and the tibias of young male rats fed a purified diet deficient in vitamin A. After about thirty to thirty-five days on the experimental diet a clear-cut vitamin A deficiency was established and suboptimal maintenance does of vitamin A had to be administered in order to keep the animals alive. The main changes observed were as follows: 1. 1. Osteoblastic activity decreased, as evidenced by a considerable retardation of the formation of immature bone in the healing tooth socket. 2. 2. Ostcoclastic activity was suppressed or entirely about. This was clearly illustrated by the failure of remodeling resorption of the immature bone formed in the sockets of the deficient animals and by the failure of the remodeling of the tibial shaft. This lack of resorption was considered to be the mechanism responsible for the main changes in bones seen in vitamin A deficiency. 3. 3. The immature bone formed in the vitamin A-deficient rats contained more and larger osteocytes than the immature bone of the controls, and their cytoplasm and cell membrances were distinctly basophilic.
David Johnson: A Leading Teacher of Cooperative Learning

(1994). David Johnson: A Leading Teacher of Cooperative Learning. Teaching Education: Vol. 6, No. 2, pp. 123-125.
The control of schedule-induced polydipsia: Frequency and magnitude of reinforcement

Abstract Rats bar-pressing for 180 45-mg food pellets per experimental session became polydipsic at fixed-interval 5 sec. As the length of the fixed-interval food schedule was increased from 2 to 120 sec with one food pellet delivered per reinforcement, the degree of polydipsia for all rats increased monotonically to a maximum. With increases in the fixed-interval length beyond 120 sec, all animals showed a decrease in the level of water intake. When two pellets were delivered per reinforcement with total number of pellets per session remaining constant, the function relating water intake per session and fixed-interval length was, for all rats, similar in shape to the one-pellet function, but below it. Water intake per reinforcement interval, however, was greater for the two-pellet reinforcement magnitude than for the one-pellet magnitude over most of the fixed-interval lengths investigated. The decrease in total session water intake in the two-pellet condition was attributable to the decreased number of reinforcement intervals and the consequent decreased number of drinking occasions per session.
The relationship between masseter force and masseter electromyogram during mastication in the monkey Macaca fascicularis.

In five adult monkeys, electromyograms (EMGs) were recorded from bipolar surface electrodes positioned over the superficial masseter and from bipolar fine-wire electrodes within both the superficial and deep masseter. Relative masseter force was estimated by measuring surface bone strain from the lateral aspect of the zygomatic arch using rosette strain gauges. Multiple step-wise regression procedures demonstrated that peak values of the averaged masseter EMG could often explain a considerable amount of the variation of peak relative masseter force during mastication, i.e. r2 values ranged from 0.23 to 0.96 for the various single-electrode models and R2 values ranged from 0.78 to 0.96 for the various multiple-electrode models. The r2 values for relative masseter force and EMG data from the surface electrodes ranged from 0.69 to 0.96, and, on average, EMG data from surface electrodes provided somewhat more information about overall relative muscle force than data from fine-wire electrodes. The R2 values for a two-electrode model, consisting of data from surface electrodes over the superficial masseter and fine-wire electrodes in the posterior portion of the deep masseter, ranged from 0.78 to 0.95. The latency between the averaged surface EMG and relative muscle force was determined and the data indicated that the surface EMG usually preceded muscle force. This latency tended to decrease gradually throughout the entire power stroke of mastication. At peak values, the surface EMG preceded muscle force by about 22 ms. Towards the end of the power stroke, i.e. the 25% of peak values during unloading, muscle force may actually precede the average EMG.
Utility of an upper echoendoscope for endoscopic ultrasonography of malignant and benign conditions of the sigmoid/left colon and the rectum

Abstract OBJECTIVE: The majority of data on colonic endoscopic ultrasound (EUS) are limited to malignant lesions in the rectum and diseases of the anal sphincter. The forward-oblique-viewing upper echoendoscope has been mostly applied for staging rectal cancer. A front-viewing echocolonoscope is available but has not been widely used because of limited indications and the expense of buying another instrument. The purpose of our study was to evaluate the utility of a forward-oblique-viewing upper echoendoscope for EUS of malignant and benign lesions of the sigmoid/left colon and the rectum. METHODS: Thirty-two EUS exams were performed for a variety of indications in the rectum and the sigmoid/left colon. The patients were prepared for the exam in a manner similar to the performance of flexible sigmoidoscopy. Flexible sigmoidoscopy was performed in all cases before performing EUS. Surgical path data were reviewed in all cases if the patient had surgery after EUS. RESULTS: Twenty-six exams were done for staging of rectosigmoid carcinoma, follow-up after chemotherapy and/or radiation, or to look for recurrence after resection of colorectal cancer. Surgical pathology results were available in 20 patients. The accuracies of EUS were 85% for T staging and 80% for N staging. Six EUS exams were for benign causes, including evaluation for the presence of a perirectal abscess in two (no abscess found), to rule out rectal varices in one (EUS confirmed rectal varices), and evaluation of submucosal lesions. One patient subsequent to EUS imaging also underwent a linear EUS-guided fine-needle aspiration of a submucosal mass in the rectum with the fine-needle aspirate consistent with a myogenic tumor. CONCLUSIONS: The forward-oblique-viewing upper echoendoscope is a versatile instrument that can be applied for EUS imaging of malignant and benign indications not only in the rectum but also in the sigmoid/left colon.
Probing helix formation in unsolvated peptides.

Ion mobility measurements have been used to examine helix formation in unsolvated glycine-based peptides containing three alanine residues. Nine sequence isomers of Ac-[12G3A]K+H+ were studied (Ac = acetyl, G = glycine, A = alanine, and K = lysine). The amount of helix present for each peptide was examined using two metrics, and it is strongly dependent on the proximity and the location of the alanine residues. Peptides with three adjacent alanines have the highest helix abundances, and those with well-separated alanines have the lowest. The helix abundances for most of the peptides can be fit reasonably well using a modified Lifson−Roig theory. However, Lifson−Roig theory fails to account for several key features of the experimental results. The most likely explanation for the correlation between helix abundances and the number of adjacent alanines is that neighboring alanines promote helix nucleation.
Xenobiotic-induced TNF-α expression and apoptosis through the p38 MAPK signaling pathway

Abstract Some xenobiotics, such as dichlorodiphenyltrichloroethane (DDT), bind to and activate estrogen receptors (ERs), eliciting estrogenic effects in both wildlife and humans. However, our laboratory and others have demonstrated that DDT and DDT-like compounds target non-ER pathways. In search for a molecular mechanism we recently established that DDT and its metabolites stimulate activator protein-1 (AP-1)-mediated gene expression through the p38 mitogen-activated protein kinase (MAPK) cascade. Here, we determined that DDT-induced p38 activity produces a novel environmental signaling pathway in endometrial Ishikawa and human embryonic kidney (HEK) 293 cells. Xenobiotic exposure stimulates expression of the death ligand, tumor necrosis factor-α (TNF-α) as demonstrated using RT-PCR and reporter gene assays. Furthermore, DDT-induced p38 activity led to the release of cytochrome c from the mitochondria and activation of caspase-3/7. Ultimately, DDT-treated cells underwent cell death. Taken together, these data demonstrate DDT induces both the expression of the death ligand TNF-α and apoptosis through a p38 MAPK-dependent mechanism.
Cytophotometric deoxyribonucleic acid studies on livers of xenogeneic radiation chimeras.

HEPATOMEGALY has been described as an early manifestation of bone marrow injection into lethally irradiated or normal mice. Congdon and Kretchmar1 reported that liver weight returned to normal in syngeneic chimeras by three weeks post-treatment, but that hepatomegaly continued in allogeneic chimeras throughout a 95-day post-treatment period. (The terms used here describe chimeras resulting from the injection of donor cells from the same strain (syngeneic), different strain (allogeneic) and different species (xenogeneic) to X-irradiated hosts.) Little information exists concerning the early phase of this tissue reaction. The nuclear DNA content of liver parenchymal cells of xenogeneic radiation chimeras during the first two weeks after treatment with rat bone marrow or spleen cells was therefore examined. Since it has been suggested1 that the enlarged liver is due to individually enlarged parenchymal cells, it was of interest to determine whether there was a shift of the parenchymal cell population to one of higher DNA content.
The strategy, effectiveness, and consistency of Federal Reserve monetary policy 1924–1933

Abstract This paper presents new empirical tests of alternative hypotheses of Federal Reserve behavior from 1924 to 1933. The Fed used open-market operations in government securities to smooth economic fluctuations, to limit stock market speculation, and to assist Great Britain to return to the gold standard. However, this study finds that during the 1920s open-market operations did not affect the volume of Federal Reserve Credit outstanding. The Fed seems to have continued to use this ineffective strategy during the depression, which can account for its failure to respond vigorously to the economic downturn.
Common hepatic artery arising from the left gastric artery: a rare anatomic variation identified on a cadaveric liver donor.

Anatomical variations of the arterial supply of the liver are not uncommon. The typical normal “textbook” anatomy of the hepatic artery is found only in approximately half of the cases. Some of the variations such as the presence of a right or left hepatic branch are more common, but other ones are extremely rare. We describe here a rare case in which the common hepatic artery arose from the left gastric artery, found during a cadaveric liver donor harvesting and confirmed with imaging studies. Cases like this one highlight the importance of knowing the hepatic arterial anatomy and the possibility of its numerous variations by the transplant and hepatobiliary surgeon.