cssi/SciSciGPT-SciSciNet huggingface dataset:
A highly integrable, compact, reliable, and low-WDL fiber-optic tap coupler

In this paper, a highly integrable, compact, reliable, and low wavelength dependent loss (WDL) fiber-optic tap coupler is presented. The coupler includes a single-fiber collimator at the input end, a grating beam deflector, a housing, and a specially designed dual-fiber collimator at the output end. One fiber of the dual-fiber collimator serves as the output channel and the other fiber serves as the tap channel. To minimize WDL induced by the wavelength-dependent diffraction efficiency of the phase grating, this dual-fiber collimator is carefully designed so that wavelength-dependent diffraction efficiency is largely compensated by the wavelength-dependent coupling efficiency of the dual-fiber collimator. A low WDL as small as 0.05 dB is achieved within the whole c-band region. The tap ratio can also be adjusted by controlling the modulation depth of the diffraction grating. Since this unique coupler can be easily integrated with other fiber-optic elements, such as variable optic attenuators (VOAs), it can be used to build a variety of fiber-optic modulates with integrated power monitoring capability. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 166–170, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10710
Comparative study of the transverse strength of three denture base materials.

Abstract Objectives Fracture resistance of recently introduced denture base resins has not been compared to traditional denture base materials. This study compared the transverse strength of three denture base materials, namely, Lucitone 199, Triad VLC, and the newly introduced Eclipse. Materials and methods A total of 30 specimens (50 mm × 25 mm × 2.5 mm) were fabricated, 10 from each material. The specimens were loaded until failure on an Instron universal testing machine using a three point flexural test. One-way analysis of variance (ANOVA) was used to compare the mean transverse strength between the three materials tested. Results The transverse strength values showed significant differences between the three denture base materials ( P Conclusions Within the limitations of this study, Eclipse showed the highest transverse strength among the materials tested. Eclipse denture base material may provide a stronger alternative to traditional denture base resins.
Microvascular Endothelial Cells Exhibit Optimal Aspect Ratio for Minimizing Flow Resistance

A recent analytical solution of the three-dimensional Stokes flow through a bumpy tube predicts that for a given bump area, there exists an optimal circumferential wavenumber which minimizes flow resistance. This study uses measurements of microvessel endothelial cell morphology to test whether this prediction holds in the microvasculature. Endothelial cell (EC) morphology was measured in blood perfused in situ microvessels in anesthetized mice using confocal intravital microscopy. EC borders were identified by immunofluorescently labeling the EC surface molecule ICAM-1 which is expressed on the surface but not in the EC border regions. Comparison of this theory with extensive in situ measurements of microvascular EC geometry in mouse cremaster muscle using intravital microscopy reveals that the spacing of EC nuclei in venules ranging from 27 to 106 μm in diameter indeed lies quite close to this predicted optimal configuration. Interestingly, arteriolar ECs are configured to minimize flow resistance not in the resting state, but at the dilated vessel diameter. These results raise the question of whether less organized circulatory systems, such as that found in newly formed solid tumors or in the developing embryo, may deviate from the optimal bump spacing predicted to minimize flow resistance.
Mechanism of Rectification in Tunneling Junctions Based on Molecules with Asymmetric Potential Drops

This paper proposes a mechanism for the rectification of current by self-assembled monolayers (SAMs) of alkanethiolates with Fc head groups (SC11Fc) in SAM-based tunneling junctions with ultra-flat Ag bottom electrodes and liquid metal (Ga2O3/EGaIn) top electrodes. A systematic physical-organic study based on statistically large numbers of data (N = 300−1000) reached the conclusion that only one energetically accessible molecular orbital (the HOMO of the Fc) is necessary to obtain large rectification ratios R ≈ 1.0 × 102 (R = |J(−V)|/|J(V)| at ±1 V). Values of R are log-normally distributed, with a log-standard deviation of 3.0. The HOMO level has to be positioned spatially asymmetrically inside the junctions (in these experiments, in contact with the Ga2O3/EGaIn top electrode, and separated from the Ag electrode by the SC11 moiety) and energetically below the Fermi levels of both electrodes to achieve rectification. The HOMO follows the potential of the Fermi level of the Ga2O3/EGaIn electrode; it overla...
Reducing obesity: motivating action while not blaming the victim

CONTEXT: The rise in obesity in the United States may slow or even reverse the long-term trend of increasing life expectancy. Like many risk factors for disease, obesity results from behavior and shows a social gradient. Especially among women, obesity is more common among lower-income individuals, those with less education, and some ethnic/racial minorities. METHODS: This article examines the underlying assumptions and implications for policy and the interventions of the two predominant models used to explain the causes of obesity and also suggests a synthesis that avoids "blaming the victim" while acknowledging the role of individuals' health behaviors in weight maintenance. FINDINGS: (1) The medical model focuses primarily on treatment, addressing individuals' personal behaviors as the cause of their obesity. An underlying assumption is that as independent agents, individuals make informed choices. Interventions are providing information and motivating individuals to modify their behaviors. (2) The public health model concentrates more on prevention and sees the roots of obesity in an obesogenic environment awash in influences that lead individuals to engage in health-damaging behaviors. Interventions are modifying environmental forces through social policies. (3) There is a tension between empowering individuals to manage their weight through diet and exercise and blaming them for failure to do so. Patterns of obesity by race/ethnicity and socioeconomic status highlight this tension. (4) Environments differ in their health-promoting resources; for example, poorer communities have fewer supermarkets, more fast-food outlets, and fewer accessible and safe recreational opportunities. CONCLUSIONS: A social justice perspective facilitates a synthesis of both models. This article proposes the concept of "behavioral justice" to convey the principle that individuals are responsible for engaging in health-promoting behaviors but should be held accountable only when they have adequate resources to do so. This perspective maintains both individuals' control and accountability for behaviors and society's responsibility to provide health-promoting environments.
Recommendations for management of trigeminal nerve defects based on a critical appraisal of the literature

Purpose: Management of trigeminal nerve injuries continues to challenge oral and maxillofacial surgeons. The purpose of this review article is to apply the principles of evidence-based medicine (E-BM) to determine the optimal operative technique for managing defects involving the inferior alveolar (IAN) or lingual nerves when direct (ie, primary) repair is not feasible. Methods: To address the research purpose, the four steps of the E-BM critical appraisal process were applied: 1) identify the clinical problem, 2) efficiently search the literature, 3) select relevant articles and apply rules of evidence, and 4) apply the findings to patient care. Parameters for the literature search included using Medline to identify English language articles, publication dates from 1986 through 1996, and studies involving human subjects. Results: The studies reviewed showed that the clinical literature on operative management of trigeminal nerve injuries is sparse, preoperative and postoperative neurosensory examinations are poorly documented, and the data are derived completely from reports using case series methods. Given these limitations, the available literature suggests that 1) tension-free, primary (direct) suture repair of an injured nerve, if possible, provides optimal results; 2) if direct repair is not possible, autogenous nerve grafts should be used for acute injuries, for example, immediate nerve repair after tumor resection or at the time of acute repair after traumatic injury; and 3) if direct repair is not possible, autogenous nerve grafts or hollow conduits (entubulization) to bridge the defect are equally successful for delayed reconstruction of gaps of 3 cm or smaller. Conclusions: Based on the weakness of the current literature, recommendations for future research include 1) better standardization and documentation of sensory deficits resulting from nerve injuries and their recovery, 2) using multicenter studies to accumulate large samples of patients rapidly, 3) using case series or prospective cohort study designs to assess the value of operative management of nerve injuries, and 4) progressing to randomized clinical trials to ascertain the optimal operative management of nerve injuries.
Impact of Clinical Pathways and Practice Guidelines on the Management of Acute Exacerbations of Bronchial Asthma

Objectives In 1990, it was estimated that approximately 1% of all US health-care costs (approximately $6.2 billion) were spent on asthma-related health expenses. Of this, hospitalization charges alone exceeded $2.6 billion. Practice guidelines and clinical pathways are being developed to standardize the management of acute asthma with the aim of improving care and safely reducing health-care costs. In this report, we evaluate the impact of an asthma pathway developed and instituted at a large community-based teaching hospital. This pathway was evidence based and was developed by a multidisciplinary group. Methods: The study was conducted during a 6-month period in 1995, while a similar period in 1994 was used as a historical control period. Data collected included patient demographics, hospital admission and discharge peak expiratory flow rates, pulse oximetry measurements, length of stay, conversion from hand-held nebulizer to metered-dose inhaler, use of corticosteroids within 24 h of hospitalization, and conversion of IV steroids to oral steroids. Results: A total of 42 patients were enrolled during the study period. Of these, 19 were placed on the pathway, while 23 were not treated according to the pathway. There were 38 patients in the 1994 historical control period. For 1995, there was no significant difference between the pathway and nonpathway groups with regard to the length of stay (4.4±3.3 vs 3.2±2.3 days; p>0.05), hospital discharge peak expiratory flow rates (324 vs 286 L/min; p 0.05). However, a significant increase in conversion from hand-held nebulizer to metered-dose inhaler was noted in the pathway group (68% vs 34%; p 0.05) and/or use of steroids (92% vs 100%; p>0.05), while a significant increase in hand-held nebulizer to metered-dose inhaler conversion was observed for the 1995 pathway group (68% vs 26%; p=0.002). Conclusions: We conclude that although the asthma pathway did not significantly reduce length of stay, it was associated with a significant increase in hand-held nebulizer to metered-dose inhaler conversion, resulting in a substantial cost savings of $288,000/year.
My Journey With Learning Logs

Learning logs, or reading response logs, are an effective reading strategy that helps students learn from text. This article reports the use of such logs, with an added element of social interaction in which students were asked to share one entry from their logs with the class. Two studies were conducted to ascertain students' perceptions of the learning value of the strategy. The first consisted of 123 undergraduate and graduate students enrolled in education courses. The second study consisted of 547 middle and high school students. After using the strategy three times, students were given a 12-question survey. One hundred percent of the college students and 98% of the middle and high schoolers reported they read at least some of the assigned text. Ninety-two percent of college students and 72% of middle and high school students reported they understood and remembered the text better when reading for interest rather than reading for a test. Ninety-four percent of college students and 65% of the middle and high school students reported they gained new perspectives from the discussions.
Regional variations of laser Doppler blood flow in ischemic skin flaps.

An island skin flap was designed on the left inferior epigastric neurovascular bundle of anesthetized male rats. Blood flow was measured in situ with a laser Doppler flowmeter at 20 discrete points on a grid system (5 points in each quadrant of the flap) before and after surgery, or before vascular occlusion, during reperfusion, and 48 to 72 hours later. Two series of experiments were performed. In the first series, the raised flap was placed in a bath containing heated Ringer's solution and the left pedicle was cross-clamped. After 30 minutes, adenosine at a concentration that produced supramaximal vasodilatation, or its vehicle, was added to the bath. After 1 hour total occlusion time, the vascular clamp was released and adenosine treatment was continued for the first 30 minutes of reperfusion. In the second series, the protocol was similar except that adenosine, or its vehicle, was infused into the ischemic flap by means of the distal stump of the right inferior epigastric artery. After 48 to 72 hours, fluorescein was injected IV. The data showed a significant regional variation in baseline laser Doppler blood flow that was further altered by surgically raising the flap. Whereas proximal axial laser Doppler blood flow was essentially unchanged from the preoperative baseline, distal axial laser Doppler blood flow decreased 10 to 50 percent, and proximal and distal dependent laser Doppler blood flow decreased 50 to 80 percent. Thus no single value accurately reflected total flap perfusion. Necrosis occurred only in the dependent flap regions, which confirmed previous work. In the dependent regions, especially along the incision line, postoperative laser Doppler blood flow was lowest. Fluorescein penetration at 48 to 72 hours was strongly correlated with laser Doppler blood flow if a correction factor of 2.3 was considered. With adenosine treatment, in contrast to its vehicle, laser Doppler blood flow tended to increase during the postoperative period. We conclude (1) that surgical construction of a skin flap can aggravate a regional variation in perfusion that can be detected with a laser Doppler flowmeter, (2) that continuous monitoring of laser Doppler blood flow at a single site could be misleading unless tissue perfusion is uniform, and (3) that adenosine has a potential beneficial effect in ischemic skin tissue.
Intercalative and nonintercalative binding of large cationic porphyrin ligands to polynucleotides

The interactions of two positional isomers and one analogue of meso-tetra (4-N-methylpyridyl) porphine, with the synthetic polynucleotides poly[d(A-T)] . poly[d(A-T)] and poly[d(G-C)] . poly[d(G-C)] have been investigated by circular dichroism. All four porphyrins were found to bind to the polynucleotides as shown by the induction of circular dichroism in their Soret bands. Furthermore, the sign of the induced ellipticity reflects selective occupation of binding sites by the porphyrin ligands. The conformational lability of poly[d(A-T)] X poly[d(A-T)] was found to be appreciable as micromolar amounts of meso-substituted 4-N-methylpyridyl, 3-N-methylpyridyl, and p-N-trimethylanilinium porphines induced a CD spectrum similar but not identical to that of DNA in the Z-form, i.e. a negative band at 280 nm and a positive band at 259 nm. The effect of porphyrin binding to poly[d(G-C)] X poly[d(G-C)] was less pronounced and dissimilar to that seen in the AT polymer.
How To Select an Effective Art Teacher

Selecting an art teacher is just as complex a task as selecting an effec tive teacher in any special field, according to this writer. In the final analysis, he says, the only certain way for a principal to do so is to learn enough about art education to feel comfortable when reviewing appli cations and interviewing applicants.
Antifungal activity of zinc oxide nanoparticles against Botrytis cinerea and Penicillium expansum

Antifungal activities of zinc oxide nanoparticles (ZnO NPs) and their mode of action against two postharvest pathogenic fungi (Botrytis cinerea and Penicillium expansum) were investigated in this study. ZnO NPs with sizes of 70 ± 15 nm and concentrations of 0, 3, 6 and 12 mmol l(-1) were used. Traditional microbiological plating, scanning electron microscopy (SEM), and Raman spectroscopy were used to study antifungal activities of ZnO NPs and to characterize the changes in morphology and cellular compositions of fungal hyphae treated with ZnO NPs. Results show that ZnO NPs at concentrations greater than 3 mmol l(-1) can significantly inhibit the growth of B. cinerea and P. expansum. P. expansum was more sensitive to the treatment with ZnO NPs than B. cinerea. SEM images and Raman spectra indicate two different antifungal activities of ZnO NPs against B. cinerea and P. expansum. ZnO NPs inhibited the growth of B. cinerea by affecting cellular functions, which caused deformation in fungal hyphae. In comparison, ZnO NPs prevented the development of conidiophores and conidia of P. expansum, which eventually led to the death of fungal hyphae. These results suggest that ZnO NPs could be used as an effective fungicide in agricultural and food safety applications.
First-principles study of field emission from carbon nanotubes and graphene nanoribbons

A real-space, real-time implementation of time-dependent density functional theory is used to study electron field emission from nanostructures. Carbon nanotubes and graphene nanoribbons are used as model systems. The calculations show that carbon nanotubes with iron adsorbates have spin-polarized emission currents. Graphene nanoribbons are shown to be good field emitters with spatial variation of the emission current influenced by the presence of passivating hydrogen.
LO2/LH2 propulsion for outer planet orbiter spacecraft

Galileo class orbiter missions (750-1500 kg) to the outer planets require a large postinjection delta-V for improved propulsion performance. The present investigation shows that a pump-fed low thrust LO2/LH2 propulsion system can provide a significantly larger net on-orbit mass for a given delta-V than a state-of-the-art earth storable, N2O4/monomethylhydrazine pressure-fed propulsion system. A description is given of a conceptual design for a LO2/LH2 pump-fed propulsion system developed for a Galileo class mission to the outer planets. Attention is given to spacecraft configuration, details regarding the propulsion system, the thermal control of the cryogenic propellants, and aspects of mission performance.
Metabolism of Inorganic N Compounds by Ammonia-Oxidizing Bacteria

Ammonia oxidizing bacteria extract energy for growth from the oxidation of ammonia to nitrite. Ammonia monooxygenase, which initiates ammonia oxidation, remains enigmatic given the lack of purified preparations. Genetic and biochemical studies support a model for the enzyme consisting of three subunits and metal centers of copper and iron. Knowledge of hydroxylamine oxidoreductase, which oxidizes hydroxylamine formed by ammonia monooxygenase to nitrite, is informed by a crystal structure and detailed spectroscopic and catalytic studies. Other inorganic nitrogen compounds, including NO, N2O, NO2, and N2 can be consumed and/or produced by ammonia-oxidizing bacteria. NO and N2O can be produced as byproducts of hydroxylamine oxidation or through nitrite reduction. NO2 can serve as an alternative oxidant in place of O2 in some ammonia-oxidizing strains. Our knowledge of the diversity of inorganic N metabolism by ammonia-oxidizing bacteria continues to grow. Nonetheless, many questions remain regarding the enzymes and genes involved in these processes and the role of these pathways in ammonia oxidizers.
Teaching Peer-Tutoring Behaviors in First- and Third-Grade Classrooms.

Peer tutoring programs represent an innovative approach for optimally utilizing resources existing within classrooms. While most tutoring programs have been aimed at helping tutees or tutors with academic difficulties, the present study involved all children in two classrooms in a peer tutoring project. A multiple baseline design indicated that prompting was effective in establishing tutoring behaviors among the children. By program end, all children were using corrective feedback, re-presenting questions, and employing contingent praise. Positive findings also were shown in academic, behavioral, and consumer satisfaction indices. In addition, 50% of children reported using peer-tutoring skills outside of the formal program.
Some aspects of the cardiovascular physiology of the duck.

Summary The following physiologic parameters were investigated in the duck: electrocardiogram in embryonic and adult subjects, respiration, respiratory-heart rate relationship, atrial and ventricular fibrillation, blood pressure, diving reflex, vagal activity, responses to atropine, acetylcholine and epinephrine and to four different anesthetic agents. An interesting and unique phenomenon noted in this species was sustained respiratory arrest following single short duration vagal stimulation. Zusammenfassung Zur Physiologie des Herz-Kreislaufsystems der Ente Bei der Ente wurden die folgenden Parameter untersucht: EKG bei Embryonen und erwachsenen Tieren, Respiration, Verhaltnis der Atmungs-frequenz zur Herzfrequenz, Vorhof- und Kammerflimmern, Blutdruck, Tauchreflex, Vagusaktivitat, Einflus von Atropin, Acetylcholin und Noradrenalin sowie von 4 verschiedenen Narkosemitteln. Hierbei wurde ein eigenartiges Phanomen festgestellt, namlich ein langerer Atmungsstillstand wahrend einer einzelnen kurzen Vagusreizung. Resume A propos de la physiologie du systeme coeur-circulation du canard On a examine les parametres suivants chez le canard: electrocardiogramme chez l'embryon et l'animal adulte, respiration, rapport de la frequence respiratoire et cardiaque, fibrillation auriculaire et ventriculaire, pression sanguine, reflexe d'immersion, activite du nerf vague, influence de l'atropine, de l'acetylcholine, de la noradrenaline et de 4 narcotiques differents. On a pu constater un phenomene particulier qui consistait en un arret prolonge de la respiration durant une seule excitation de courte duree Resumen Sobre la fisiologia cardiocirculatoria en el pato Se examinaron en patos los parametros fisiologicos siguientes: ECG en embriones y animales adultos, respiracion, relacion de la frecuencia respiratoria a la cardiaca, fibrilacion atrial y ventricular, presion sanguinea, reflejo de zambullida, actividad vagal, respuestas a la atropina, acetilcolina y epinefrina, asi como a 4 anestesicos diferentes. Aqui se evidencio un fenomeno particular, consistente en la detencion respiratoria sostenida subsiguiente a una estimulacion vagal unica de duracion breve.
Te surfactant effects on the morphology of patterned (0 0 1) GaAs homoepitaxy

Abstract The surfactant effects of tellurium on GaAs homoepitaxy were studied by introducing diethyltelluride (DETe) during growth on (0 0 1) patterned substrates. The DETe partial pressure was systematically varied from 0 to 2.9×10 −4 Torr . An impurity concentration of 9.0×10 18 cm −3 was estimated from 4-point probe measurements for the sample grown with the highest DETe flow rate. The presence of Te on the growing surface had no detectable effect on the lateral growth rates of the patterned mesas, but had a dramatic effect on the evolution of the mesa profiles and the surface morphology. The surfactant Te reduced the rms roughness from 5 to 0.5 nm, produced trenches and pits on the surface, and caused an increase in the sidewall angles of pits, trenches, and patterned mesas. The increase in sidewall angle is consistent with “slope selection” theory, and correlates to an increase in the Ehrlich–Schwoebel (ES) barrier. Kinetic simulations support the hypothesis that increased sticking at steps and an increased ES barrier are the mechanisms by which tellurium changes the surfaces morphology.
How sexual harassment changed the way I work

As a flurry of interest in workplace discrimination subsides, efforts to raise awareness and eliminate abuses continue, says Kathleen Raven.
Biosynthesis of pregnenolone from cholesterol in punica granatum

Abstract Following administration of cholesterol-4- 14 C to leaves of Punica granatum plants, radioactive pregnenolone was isolated and identified by thin-layer and gas chromatography and the formation of the acetate derivative.
The transport and metabolism of l-proline-14C in the rat in vivo

Abstract The physiologic disposition, metabolic fate, and renal clearance of intravenously injected 14 C- l -proline was determined in the rat. The disappearance of radioactivity from plasma occurred with a biphasic curve, the initial high levels reaching a nadir about 30 min after injection with subsequent increasing amounts of radio-activity. Examination of the 14 C components in plasma revealed that 14 C-proline disappeared rapidly during the first 30 min. At this time, the labeling of circulating plasma proteins ensued and continued to increase during the following 45 min of observations. Plasma glucose became labeled 10 min after injection and, thereafter, increased its 14 C content. The extensive labeling of plasma proteins and glucose accounted for the increasing 14 C found in plasma 30 min after injection. The course of radioactive labeling of brain, kidney, diaphragm, and liver was assessed. The greatest number of cpm/mg of tissue was found in the kidney. Determination of the distribution ratio, the ratio of cpm/ml intracellular nonprotein 14 C to that in plasma in kidney revealed a peak of 3.9 within 15 min, a value comparable to that found in vitro. Twelve percent of the administered radioactivity was excreted as 14 CO 2 within 180 min. The oxidation was inhibited by known transport and metabolic inhibitors, the greatest effect observed with hydroxyproline, followed in order by thioproline, 3,4-dihydroproline, and glycine. The fractional urinary excretion of proline, C proline C inulin , was determined and found to be 1% or less. This was increased by inhibitors, the greatest effect due to hydroxyproline followed in order by dehydroproline and glycine, a result similar to the observed extent of inhibition of proline oxidation to 14 C O 2 . The physiologic disposition of proline was not altered by ligation of the renal vasculature.
Recent Advances in UC-PBG Structures

This paper summaries recent progress of uniplanar compact photonic band-gap (UC-PGB) structure at the author's group, including: (1) coupled lines on UC-PBG ground plane, (2) cavity-backed slot antenna using UC-PBG as a reflector, and (3) TEM waveguide.
The Integrin Ligand Echistatin Prevents Bone Loss in Ovariectomized Mice and Rats

Integrins that bind RGD (arginine-glycine-aspartic acid) containing peptides, especially the vitronectin receptor alpha(v)beta3, have been implicated in the regulation of osteoclast function. Echistatin, an RGD-containing snake venom peptide with high affinity for beta3 integrins, as well as nonpeptide RGD mimetics, were shown to inhibit osteoclastic bone resorption in vitro and in vivo. To evaluate the role of RGD-binding integrins in bone metabolism, we examined by several methods the effects of echistatin on ovariectomy (OVX)-induced bone loss in mice and rats. First, we confirmed that echistatin binds in vitro with high affinity (Kd, 0.5 nM) to alpha(v)beta3 integrin purified from human placenta and established a competitive binding assay to measure echistatin concentrations in serum. We find that echistatin infused for 2 or 4 weeks at 0.36 microg/h x g body weight (approximately 50 nmol/day x mouse) completely prevents OVX-induced cancellous bone loss in the distal femora of ovariectomized mice. Echistatin has no effect on uterine weight, body weight, and femoral length changes induced by OVX, nor does it cause any apparent changes in major organs other than bone. In OVX rats, echistatin infusion at 0.26 microg/h x g for 4 weeks effectively prevents bone loss, evaluated by dual energy x-ray absorptiometry of the femur, by femoral ash weight, and by bone histomorphometry of the proximal tibia. At effective serum concentrations of 20-30 nM, measured at the end of the infusion period, echistatin maintains histomorphometric indices of bone turnover at control levels but does not decrease osteoclast surface. In conclusion, these results provide in vivo evidence, at the level of bone histology, that RGD-binding integrins, probably alpha(v)beta3, play a rate-limiting role in osteoclastic bone resorption and suggest a therapeutic potential for integrin ligands in the suppression of bone loss.
The effects of graft tensioning on the laxity and kinematics of the anterior cruciate ligament reconstructed knee

An in vitro study of eight cadaveric knees was conducted to investigate the effect of initial graft tension on the laxity and full three-dimensional kinematics of the anterior cruciate ligament reconstructed knee. A parallel strand, prototype, expanded polytetrafluoroethylene graft (W. L. Gore and Associates, Flagstaff, AZ, U.S.A.) was used. The graft was placed in the over-the-top position with initial tensions of 18, 36, 54, 72, and 90 N applied with the knee in full extension or at 30 degrees of flexion. The motion of the tibia relative to the femur was measured by a 6 degrees-of-freedom spatial linkage, and the applied forces and moments, the quadriceps force, and the graft tension were measured by load cells. Near normal anterior laxity in the Lachman test was restored with all the tested initial graft tensions. However, over constraint, posterior, lateral, and external tibial subluxation, and abnormalities in joint stiffness developed as the initial graft tension increased. Graft tension-related posterior tibial subluxation resulted in an increase in quadriceps force needed to achieve full extension.
An Inside View of Gifted Education in Russia.

This article provides an “insider's” perspective on gifted education in Russia. The first author, formerly a teacher at a Moscow residential math/physics school for the gifted, collected cognitive and social data from her students. We provide some historical context for the development of special schools in the former Soviet Union, present and discuss the data on the Russian students, relate some case studies of gifted Russian students, and review some of the academic and social issues that arise with this kind of schooling. American readers may find that the results of the study, the student descriptions, and the issues that arise in programming for gifted students are surprisingly familiar.
Two New Substrates in Insulin Signaling, IRS5/DOK4 and IRS6/DOK5

We have identified two new human genes that encode proteins with tandem pleckstrin homology-phosphotyrosine binding (PH-PTB) domains at their amino termini. Because the other known PH-PTB proteins (insulin receptor substrates: IRS-1, IRS-2, IRS-3, and IRS-4, and the downstream of kinases: DOK-1, DOK-2, and DOK-3) are substrates of insulin and insulin-like growth factor (IGF)-1 receptors, we asked whether these new proteins, termed IRS5/DOK4 and IRS6/DOK5, might also have roles in insulin and IGF-1 signaling. Northern analyses indicate that IRS5/DOK4 is ubiquitously expressed but most abundant in kidney and liver. IRS6/DOK5 expression is highest in skeletal muscle. Both proteins are tyrosine-phosphorylated in response to insulin and IGF-1 in transfected cells, although the kinetics differ. Insulin receptor-phosphorylated IRS5/DOK4 associates with RasGAP, Crk, Src, and Fyn, but not phosphatidylinositol 3-kinase p85, Grb2, SHP-2, Nck, or phospholipase Cγ Src homology 2 domains, and activates MAPK in cells. IRS6/DOK5 neither associates with these Src homology 2 domains nor activates MAPK. IRS5/DOK4 and IRS6/DOK5 represent two new signaling proteins with potential roles in insulin and IGF-1 action.
Covalent change in alpha crystallin during human senile cataractogenesis

Abstract The high molecular weight aggregates (HMWA) obtained from normal and cataractous human lens nuclei have been resolved by SDS-polyacrylamide gel electrophoresis, and the alpha crystallin band has been probed with antisera made against the whole alpha crystallin molecule and with antisera made against synthetic peptides of alpha crystallin (alphaA2 147–161 and alpha A2 163–173). Quantitation of these antisera binding demonstrated that the anti-alphaA2 163–173 serum and the anti-alphawhole sera bound equally well to the alpha crystallin band from the HMWA fraction from normal and cataractous lenses. In contrast, the anti-alphaA2 147–161 serum bound little, if at all, to alpha crystallin from normal lenses, while it bound well to alpha crystallin from cataractous lenses. These results demonstrate a covalent alteration in the alpha crystallin molecule, and suggest a possible location of a covalent change that may occur during the cataractogenic process in the aged human lens.
RADIOCHEMICAL DETERMINATION OF As, Cr, Mo, Sb AND Se IN FOODS

A radiochemical neutron activation analysis procedure was applied to the analysis of foods for As, Cr, Mo, Sb and Se. The elements are retained on an inorganic chromatographic resin of hydrated managanese dioxide while interfering elements are removed. Activities from Br, K, Na and P interferences are reduced by up to six orders of magnitude, and detection limits for food analysis are reduced by factors of 100–2000, compared with those normally found for instrumental neutron activation analysis. Detection limits for the foods analyzed are 0.1–0.3 ng/g for As and Sb and 1–10 ng/g for Cr, Mo and Se. Results are presented for various foods and several National Bureau of Standards Standard Reference Materials.
Unusual Cu(I)/Ag(I) coordination of Escherichia coli CusF as revealed by atomic resolution crystallography and X‐ray absorption spectroscopy

Elevated levels of copper or silver ions in the environment are an immediate threat to many organisms. Escherichia coli is able to resist the toxic effects of these ions through strictly limiting intracellular levels of Cu(I) and Ag(I). The CusCFBA system is one system in E. coli responsible for copper/silver tolerance. A key component of this system is the periplasmic copper/silver-binding protein, CusF. Here the X-ray structure and XAS data on the CusF-Ag(I) and CusF-Cu(I) complexes, respectively, are reported. In the CusF-Ag(I) structure, Ag(I) is coordinated by two methionines and a histidine, with a nearby tryptophan capping the metal site. EXAFS measurements on the CusF-Cu(I) complex show a similar environment for Cu(I). The arrangement of ligands effectively sequesters the metal from its periplasmic environment and thus may play a role in protecting the cell from the toxic ion.
Various mycorrhizal fungi propagated on different hosts have different effect on citrus growth and nutrient uptake

Citrus cultivation is expected to expand in the Cukurova Region (East Mediterranean coast of Turkey). The aim of this study was to screen and select the most suitable arbuscular mycorrhizae (AM) for enhancing citrus growth by improving phosphorus (P) and zinc (Zn) uptake of plants. This study was carried out in a glasshouse at the Department of Soil Science, Cukurova University, Adana, Turkey. Five different mycorrhizal species were tested in the first and second experiment. The AM fungi used were Glomus, mosseae (UK), G. mosseae (USA), G. clarium, G. caledonium and G. etunicatum which were propagated in Experiment I on clover, and in Experiment II on maize. Experiments were performed in autoclaved soil+organic matter+sand (2:1:7 V) as a growth media. Orange (Citrus sinensis L.) seedlings grown in containers in a glasshouse were inoculated with the 5 AM species. There were significant differences between species in growth, nutrient uptake and percentage of mycorrhizal infection for both experiments. Glomu...
Lessons learned from the Pioneers 10/11 for a mission to test the Pioneer anomaly

Abstract Analysis of the radio-metric tracking data from the Pioneer 10/11 spacecraft at distances between 20 and 70 astronomical units (AU) from the Sun has consistently indicated the presence of an anomalous, small, constant Doppler frequency drift. The drift is a blue-shift, uniformly changing with rate ∼6 · 10 −9 Hz/s. It can also be interpreted as a constant acceleration of a P = (8.74 ± 1.33) × 10 −8 cm/s 2 directed towards the Sun. Although it is suspected that there is a systematic origin to the effect, none has been found. As a result, the nature of this anomaly has become of growing interest. Here, we discuss the details of our recent investigation focusing on the effects both external to and internal to the spacecraft, as well as those due to modeling and computational techniques. We review some of the mechanisms proposed to explain the anomaly and show their inability to account for the observed behavior of the anomaly. We also present lessons learned from this investigation for a potential deep-space experiment that will reveal the origin of the discovered anomaly and also will characterize its properties with an accuracy of at least two orders of magnitude below the anomaly’s size. A number of critical requirements and design considerations for such a mission are outlined and addressed.
Chemical variations of hydrothermal particles in the 1996 Gorda Ridge Event and chronic plumes

Abstract In response to the 1996 magmatic intrusion on the Gorda Ridge near 42.68°N, 126.78°W in late February, we conducted three cruises to the region in March, April, and June. On all three cruises particulate samples were collected, along with CTD/nephelometer data and total dissolved Fe and Mn samples. During each cruise, we collected samples from large oblate spheroid-shaped event plumes. These event plumes had long axis diameters of about 10–15 km and ranged in depth from about 1800 to 2700 m. A strong linear correlation between nephelometer voltage and particulate Fe allowed us to estimate the total amount of particulate Fe in the event plumes at approximately 20×10 6 moles of Fe, or ∼28% of the Fe in the 1986 megaplume on the Cleft Segment of the Juan de Fuca Ridge. We observed significant decreases in particulate Cu and Zn concentrations (>100% decrease in Cu/Fe and Zn/Fe ratios) between the Gorda Ridge event plumes. These results suggest that each of the two event plumes originated from a chemically distinct source fluid. Fe ferrihydrite particles maintained a constant ratio of coprecipitated oxyanion species in the two event plumes. Based upon the chemical inventories for particulate Fe, P, and V, we suggest that event plumes might play a small role in the geochemical budgets for these elements.
Diacylglycerol as a component of the signal-coupling pathway during the initiation of endocytosis in Amoeba proteus

In an attempt to define the transmembrane-signal pathway used to couple external phagocytotic signals with effectors in the cell interior, the effects of diacylglycerol (DG) and related substances were examined in Amoeba proteus. DGs are highly chemotactic, readily attracting amoebae when presented in a glass micropipette. Addition of DG (10-6 M) to the medium elicits rapid shape changes in the amoeba and the formation of large phagosomes. Monacylglycerol and 1,3-diacylglycerol were much less effective in eliciting phagosome formation. On the assumption that DG was stimulating phosphokinase C (PKC) activity in the amoeba, the effect of phorbol myristate acetate (PMA), a known activator of PKC activity i other cell systems, was assessed in the amoeba. PMA (10-7 M) alone was capable of bringing about shape changes in amoebae as well as stimulating the formation of phagosomes. These observations suggest that PKC is involved in the signal-coupling associated with the onset of phagocytosis. On the other hand staurosporine and H-7, inhibitors of PKC activity in some cell systems, did not inhibit the phagocytic uptake of Tetrahymena by A. proteus. It may be then that DGs in the amoeba interact directly with elements of the cytoskeleton causing phagosome formation, although a role for PKC in the initiation of phagocytosis in the amoeba cannot be ruled out at this point.
Dynamic instability of undamped bellows face seals in cryogenic liquid.

Dynamic instability in undamped bellows face seals operating in cryogenic environment with torsional oscillation and diametrical rocking as primary motion
Classroom teacher leadership: service-learning for teacher sense of efficacy and servant leadership development

Improved student achievement requires the distribution of leadership beyond one individual. Given their daily connection to students, leadership opportunities distributed to classroom teachers are key to school improvement. Complicating the development of classroom teacher leaders are attrition rates and low teacher efficacy among novice educators. Service-learning and servant leadership offer complementary pedagogical and philosophical approaches to shift the role of classroom teachers and address efficacy concerns. This study utilised a pre-/post-test, quasi-experimental research design to determine to what extent changes would occur over time in pre-service educators’ teacher sense of efficacy and sense of servant leadership from participating in service-learning.
Geoarchaeological dating of Holocene stream terraces along the San Pedro River, southeastern Arizona, USA

Three Pleistocene and four Holocene floodplain terraces were differentiated along the San Pedro River in southeastern Arizona during a geological mapping project conducted by the Arizona Geological Survey. We used archaeological chronometric data to refine age estimates for the Holocene surfaces that had been initially based on only geomorphic and pedologic criteria. Eight archaeological sites deeply buried in the fill of the most extensive Holocene terrace map unit (Qy2r) yielded 10 radiocarbon dates and temporally diagnostic San Pedro complex (3150–1900 cal BP) artifacts. Twenty sites recorded on the surface of Qy2r terrace treads contained numerous temporally diagnostic Hohokam (1950–500 cal BP) ceramic sherds and features. The age constraints provided by these archaeological materials suggest that the Qy2r terrace fill was deposited primarily between 4500 and 1000 cal BP, with only a thin veneer of flood deposits added between 1000 and 100 cal BP. This late Holocene to historical (4500–100 cal BP) age estimate is consistent with other alluvial histories in the greater Gila River drainage basin and supplants our initial geologically based latest Holocene to historical (<2000 cal BP) Qy2r age estimate. The archaeologically derived maximum age estimate for Qy2r also provides a minimum age for the topographically higher and older Qy1r terrace, prompting us to revise our original, early to late Holocene age estimate for Qy1r to an early to middle Holocene age range of 11,500–4500 cal BP. The post-A.D. 1850 historical age we originally proposed for the Qy3r terrace deposits inset into Qy2r, however, is consistent with the presence of four historical period surface sites and a concordant absence of surface and buried prehistoric sites.
Pretreatment with lidocaine does not inhibit the maxillary sinus eosinophilic response after nasal allergen challenge

Abstract Rationale We have shown eosinophilia in the maxillary sinuses after nasal allergen challenge. We evaluated the effect of anesthetizing the nasal cavity on this response. Methods Eleven subjects with seasonal allergic rhinitis, out of season, participated in a randomized, cross-over study. One nasal cavity was pretreated with either neosynephrine and lidocaine or neosynephrine alone prior to and during challenge with diluent and 3 doses of either grass or ragweed. Nasal symptoms were recorded and nasal and sinus lavages were performed at 10-minute intervals after the challenges [early phase response (EPR)] and hourly for 8 hours after the last allergen challenge [late phase response (LPR)]. Levels of albumin were measured and numbers of eosinophils counted. Results Lidocaine treatment resulted in a significant decrease in nasal sensation compared to the non-anesthesized day. On the lidocaine day, subjects had significantly worse runny nose (3 vs 1) and itchy throat scores (2 vs 0) during the EPR (p Conclusions Pretreatment with lidocaine did not inhibit the maxillary sinus response after nasal challenge. This suggests that either the lidocaine did not completely inhibit the neurogenic reflexes, or that systemic allergic inflammation is a more likely explanation for our observations.
The δ subunit of AP-3 is required for efficient transport of VSV-G from the trans-Golgi network to the cell surface

Vesicular stomatitis virus glycoprotein (VSV-G) is a transmembrane protein that functions as the surface coat of enveloped viral particles. We report the surprising result that VSV-G uses the tyrosine-based di-acidic motif (-YTDIE-) found in its cytoplasmic tail to recruit adaptor protein complex 3 for export from the trans-Golgi network. The same sorting code is used to recruit coat complex II to direct efficient transport from the endoplasmic reticulum to the Golgi apparatus. These results demonstrate that a single sorting sequence can interact with sequential coat machineries to direct transport through the secretory pathway. We propose that use of this compact sorting domain reflects a need for both efficient endoplasmic reticulum export and concentration of VSV-G into specialized post-trans-Golgi network secretory-lysosome type transport containers to facilitate formation of viral coats at the cell surface.
Patuxent Landscape Model: 4. Model Application

Using the LHEM/SME the Patuxent Landscape Model (PLM) was built to simulate fundamental ecological processes in the watershed scale driven by temporal (nutrient loadings, climatic conditions) and spatial (land use patterns) forcings. The model addresses the effects of both the magnitude and spatial patterns of land use change and agricultural practices on hydrology, plant productivity, and nutrient cycling in the landscape.
Architecting phase change memory as a scalable dram alternative

Memory scaling is in jeopardy as charge storage and sensing mechanisms become less reliable for prevalent memory technologies, such as DRAM. In contrast, phase change memory (PCM) storage relies on scalable current and thermal mechanisms. To exploit PCM's scalability as a DRAM alternative, PCM must be architected to address relatively long latencies, high energy writes, and finite endurance.We propose, crafted from a fundamental understanding of PCM technology parameters, area-neutral architectural enhancements that address these limitations and make PCM competitive with DRAM. A baseline PCM system is 1.6x slower and requires 2.2x more energy than a DRAM system. Buffer reorganizations reduce this delay and energy gap to 1.2x and 1.0x, using narrow rows to mitigate write energy and multiple rows to improve locality and write coalescing. Partial writes enhance memory endurance, providing 5.6 years of lifetime. Process scaling will further reduce PCM energy costs and improve endurance.