cssi/SciSciGPT-SciSciNet huggingface dataset:
Behavioral response of Lake Michigan Daphnia mendotae to Mysis relicta

We performed laboratory experiments to determine if Mysis relicta induce changes in the behavior of Daphnia mendotae collected from Lake Michigan. Laboratory results indicate that Daphnia perceived Mysis kairomones and responded by changing their vertical position in cylinders. Experiments using different resource levels, and two procedures to examine the potential effects of the chemical cues from Mysis or from particulate matter or bacteria associated with capture and defecation of prey, suggest that Daphnia detect Mysis via a chemical cue. This is the first laboratory study that we are aware of that indicates that a zooplankton species from the Great Lakes responds behaviorally to an invertebrate predator. Our findings support the hypothesis that changes in vertical distribution of zooplankton associated with changes in invertebrate predator density, observed in previous Great Lakes studies, is due to behavioral responses to reduce predation risk. It is important to understand and quantify such responses, because predator-induced changes in prey behavior represent trait-mediated interactions that can potentially strongly affect prey growth rates, and indirectly affect resources, competitors, and predators of the prey.
Cold War, Public Opinion, and Foreign Policy Spending Decisions: Dynamic Representation by Congress and the President

Conventional wisdom before the Vietnam War held that public opinion exerted no influence on U.S. foreign policy decisions. Scholars working in Vietnam's aftermath found episodic influence of public opinion on foreign policy, but missing in our understanding were longitudinal examinations of public opinion's influence on foreign policy. A number of post-Vietnam scholars subsequently revealed a long-term relationship between public opinion and defense spending. This study extends that work by analyzing responsiveness to public opinion in different foreign policy arenas by different government institutions, and by accounting for a critical variable not relevant in most previous studies: the end of the cold war. We construct a model explaining the influences of public opinion and the cold war on spending proposals for defense and foreign economic aid by the presidency, the House of Representatives and the Senate. Both public opinion and the end of the cold war exert direct influence on defense spending propos...
Atomic information in the characterization of atomic photoionization

We show that atomic photoionization at all energies can be described in terms of nuclear Coulomb properties plus a limited number of atomic screening parameters. Our results support the conclusion that only screening corrections to the lowest multipoles are needed for photoionization differential cross sections. Quadrupole screening can be important except in the lightest atoms, while octupole screening is important in inner shells of intermediate-$Z$ atoms and in all shells of high-$Z$ atoms. We provide a simple way to predict in what energy ranges and for what ejection angles $\ensuremath{\theta}$ quadrupole and octupole screening effects are greatest.
Computer Program for a Double Exponential Equation to Determine Biological Constants

A new computer program in Fortran II (with Format) for the equation, C = a 0 k a V d ( k a − k d ) ⋅ ( e − k d t − e − k a t ) , has been written. This program overcomes the problems of the previous programs published. A grid method was used to search for the constants and a method to handle exponential overflow was included. Applicability of the equation and the computer program was demonstrated on the IBM 1410 computer system with eight different sets of data from the literature. The data represented a variety of drugs, i.e., sulfaethylthiadiazole, aspirin alone or with additives, oxazepam, penicillin salts, and trimeprazine, in a variety of dosage forms. The conclusions of the authors were verified by the calculated constants. In some instances the conclusions of the originators of the data could be expanded by the use of the calculated constants.
Photoconductivity and photoluminescence of amorphous chalcogenides

Abstract Experimental data on photoconductivity and photoluminescence of amorphous chalcogenides are reviewed and are examined by means of a simple model in which most of the carriers created by the light drop into localized states before recombining bimolecularly.
Impacts of Government Policies, Fuel Cell Cost, and Battery Cost on Greenhouse Gas Emission of Light-Duty Vehicles

The aim of this paper is to study the impact of public government policies, fuel cell cost, and battery cost on greenhouse gas (GHG) emissions in the US transportation sector. The model includes a government model and an enterprise model. To examine the effect on GHG emissions that fuel cell and battery cost has, the optimization model includes public policy, fuel cell and battery cost, and a market mix focusing on the GHG effects of four different types of vehicles, 1) gasoline-based 2) gasoline-electric hybrid or alternative-fuel vehicles (AFVs), 3) battery-electric (BEVs) and 4) fuel-cell vehicles (FCVs). The public policies taken into consideration are infrastructure investments for hydrogen fueling stations and subsidies for purchasing AFVs. For each selection of public policy, fuel cell cost and battery cost in the government model, the enterprise model finds the optimum vehicle design that maximizes profit and updates the market mix, from which the government model can estimate GHG emissions. This paper demonstrates the model using FCV design as an illustrative example.Copyright © 2013 by ASME
The co-adsorption of oxygen and hydrogen on Rh(111)☆

Abstract The co-adsorption of oxygen and hydrogen on Rh(111) at temperatures below 140 K has been studied by thermal desorption mass spectrometry, Auger electron spectroscopy, and lowenergy electron diffraction. The co-adsorption phenomena observed were dependent upon the sequence of adsorption in preparing the co-adsorbed overlayer. It has been found that oxygen extensively blocks sites for subsequent hydrogen adsorption and that the interaction splits the hydrogen thermal desorption into two states. The capacity of the oxygenated Rh(111) surface for hydrogen adsorption is very sensitive to the structure of the oxygen overlayer, with a disordered oxygen layer exhibiting the lowest capacity for hydrogen chemisorption. Studies with hydrogen pre-adsorption indicate that a hydrogen layer suppresses completely the formation of ordered oxygen superstructures as well as O 2 desorption above 800 K. This occurs with only a 20% reduction in total oxygen coverage as measured by Auger spectroscopy.
A quality assurance program for monitor unit calculators.

A quality assurance protocol has been developed to assess the relative accuracy of computerized monitor unit calculations. Results from this testing reveal that errors (defined as the difference between the computer results and those obtained using a standard formula with manual calculation) in monitor unit calculators are possible when they are tested over a wide range of clinically relevant field sizes (including blocked fields), source‐to‐surface distances, and depths. It is suggested that computerized monitor unit calculators be checked against hand calculations and that this be permanently documented both at the time of initial implementation and following any subsequent changes in the program.
Biaxial compression of a thin layer with circular debonding over a substrate

Abstract This paper presents an analytical solution to the problem of a circular debonded thin film on a substrate subjected to biaxial compressive residual stresses. Contaminated regions may be the source of debonding during fabrication, and compressive stresses are induced in the film during the cooling stage of the fabrication process. The presence of such defects may influence the thermal/mechanical integrity of, for example, microelectronic devices. The stress intensity factors for this problem are obtained by solving a system of singular integral equations.
Behavioral Response to Larval Tracks and the Influence of Tracks on Intraguild Scavenging by Coccinellid Larvae

A paired design was used to determine that Harmonia axyridis 4th instars were not influenced by the presence of conspecific larval tracks, but well-fed H. axyridis 4th instars spent less time on plants that contained tracks left by Coleomegilla maculata 4th instars. To determine if the presence of larval tracks influences intraguild scavenging by H. axyridis 4th instars, dead 4th instars were placed in Petri dishes that contained or did not contain larval tracks. The presence of larval tracks did not influence the feeding frequency or the amount of time before feeding. However, larvae dragged their pygopod on dish surfaces more frequently if the dish contained larval tracks. In addition, starved H. axyridis larvae were more likely to feed on the prey and dragged their pygopod less frequently than well-fed larvae.
Comparative analysis of single-species and polybacterial wound biofilms using a quantitative, in vivo, rabbit ear model.

Introduction The recent literature suggests that chronic wound biofilms often consist of multiple bacterial species. However, without appropriate in vivo, polybacterial biofilm models, our understanding of these complex infections remains limited. We evaluate and compare the effect of single- and mixed-species biofilm infections on host wound healing dynamics using a quantitative, in vivo, rabbit ear model.
The myosin cardiac loop participates functionally in the actomyosin interaction.

The motor protein myosin in association with actin transduces chemical free energy in ATP into work in the form of actin translation against an opposing force. Mediating the actomyosin interaction in myosin is an actin binding site distributed among several peptides on the myosin surface including surface loops contributing to affinity and actin regulation of myosin ATPase. A structured surface loop on β-cardiac myosin, the cardiac or C-loop, was recently demonstrated to affect myosin ATPase and was indirectly implicated in the actomyosin interaction. The C-loop is a conserved feature of all myosin isoforms with crystal structures, suggesting that it is an essential part of the core energy transduction machinery. It is shown here that proteolytic digestion of the C-loop in β-cardiac myosin eliminates actin-activated myosin ATPase and reduces actomyosin affinity in rigor more than 100-fold. Studies of C-loop function in smooth muscle myosin were also undertaken using site-directed mutagenesis. Mutagenesis of a single charged residue in the C-loop of smooth muscle myosin alters actomyosin affinity and doubles myosin in vitro motility and actin-activated ATPase velocities, thereby involving a charged region of the loop in the actomyosin interaction. It appears likely that the C-loop is an essential electrostatic binding site for actin involved in modulation of actomyosin affinity and regulation of actomyosin ATPase velocity.
Quarternary solid solution superconductors

Abstract Small amounts of Y, Gd, and Th, when added to high oxygen Nb-Ti alloys, have been found to increase the workability of such alloys as well as their critical superconducting current density appreciably.
Spin-charge separation is the key to the high Tc cuprates

Abstract The most striking fact about the high-Tc cuprates is that in none of the relevant regions of the phase diagram is there any evidence of the usual effects of phonon or impurity scattering. This is strong evidence that these states are in a “quantum protectorate” to borrow Laughlin's terms. (Two striking experimental facts which demonstrate this are the absence of phonon self-energy in ARPES measurements, demonstrated recently by Johnson in BSCCO [1], and the scattering-independent Tc in YBCO, even though the superconductivity is d-wave.) A quantum protectorate is a state in which the many-body correlations are so strong that the dynamics can no longer be described in terms of individual particles, and therefore perturbations which scatter individual particles are not effective.
Playmate Preferences and Perceptions of Individual Differences among Typically Developing Preschoolers.

The purpose of this study was to describe preschoolers’ playmate preferences and perceptions of classmates with and without disabilities using a peer rating task and a corresponding teacher rating scale. Participants consisted of 34 typically developing preschoolers ranging in age from 42 to 69 months and 5 classroom teachers. Although preschoolers with disabilities received lower sociometric ratings than their typically developing peers, the reasons children cited for selecting or rejecting their peers with disabilities were essentially the same as those given for nondisabled children. In dyads In which one child had disabilities and the other did not, teachers reported that approximately 50% preferred not to play with each other, whereas reciprocal nonpreference was reported to occur in only 21 % of dyads in which both partners were typically developing. The proportions of mutual playmate preferences in the two types of dyads were roughly equivalent, suggesting that children with disabilities are capabl...
Latest Pleistocene and Holocene glacier fluctuations in the Himalaya and Tibet

Abstract The timing and extent of latest Pleistocene and Holocene alpine glacier fluctuations in the Himalaya and Tibet are poorly defined due to the logistical and political inaccessibility of the region, and the general lack of modern studies of the glacial successions. Nevertheless, renewed interest in the region and the aid of newly developing numerical dating techniques have provided new insights into the nature of latest Pleistocene and Holocene glacier oscillations. These studies provide abundant evidence for significant glacial advances throughout the Last Glacial cycle. In most high Himalayan and Tibetan regions glaciers reached their maximum extent early in the Last Glacial cycle. However, true Last Glacial Maximum glacier advances were significantly less extensive. Notable glacier advances occurred during the Lateglacial and the early Holocene, with minor advances in some regions during the mid-Holocene. There is abundant evidence for multiple glacial advances throughout the latter part of the Holocene, although these are generally very poorly defined, and were less extensive than the early Holocene glacier advances. The poor chronological control on latest Pleistocene and Holocene glacial successions makes it difficult to construct correlations across the region, and with other glaciated regions in the world, which in turn makes it hard to assess the relative importance of the different climatic mechanisms that force glaciation in this region. The Lateglacial and Holocene glacial record, however, is particularly well preserved in several regions, notably in Muztag Ata and Kongur, and the Khumbu Himal. These successions have the potential to be examined in detail using newly developing numerical dating methods to derive a high-resolution record of glaciation to help in paleoclimatic reconstruction and understanding the dynamics of climate and glaciation in the Himalaya and Tibet.
Ultraviolet photoalteration of ion channels in voltage-clamped lobster giant axons

An analysis of the ultraviolet light-induced changes in ionic conductances of lobster giant axon membranes has been carried out using the double sucrose gap voltage-clamp technique. The predominant effect of monochromatic light from a xenon arc source in the 255 to 305 nm region is an irreversible reduction in the magnitude of sodium conductance, without change in sodium channel activation or inactivation kinetics. A considerably smaller reduction in the magnitude of potassium conductance occurs, with some slowing of potassium channel activation kinetics. Leakage conductance is essentially not altered. The fall in sodium conductance follows an exponential time course toward a zero asymptote. The rate constant for conductance decrease was used as an assay for the wavelength dependence. The sodium conductance was maximally sensitive at 290 nm. It is suggested that individual sodium channels are closed upon absorption of single photons by aromatic amino acid residues in membrane proteins.
Fully endoscopic retrosigmoid approach for posterior petrous meningioma and trigeminal microvascular decompression

Cerebellopontine angle tumor resection and cranial nerve microvascular decompression are usually performed with the aid of the surgical microscope. The endoscope is commonly used as an adjuvant. A retrosigmoid craniectomy is done. Upon dural opening, the endoscope is inserted into the operative field along the petrotentorial junction. Cerebrospinal fluid drainage provides a wider space for introduction of the endoscope and surgical instruments. Traditional microsurgical techniques are used during the entire procedure. A fully endoscopic retrosigmoid approach is a safe and effective procedure for cerebellopontine angle tumor resection and cranial nerve microvascular decompression. • Careful examination of preoperative studies is needed to identify anatomical peculiarities. • Patient positioning: the head must be gently flexed and its vertex gently tilted toward the floor. • Neurophysiologic monitoring and intraoperative navigation. • Craniectomy: partial exposure of the transverse and sigmoid sinuses. • Curvilinear dural incision reflected laterally to minimize the risk of sinus injury. • Opening the cerebellomedullary cistern for CSF drainage and cerebellar relaxation. • Dynamic endoscopy enhances depth perception and must be performed by a team with experience in endoscopic intracranial surgery. • Traditional microsurgical techniques have to be applied during the entire operation. • Multilayer reconstruction, including watertight dural closure. • Meningiomas causing brainstem shift are not suitable for endoscopic resection.
Nondiabetic consequences of obesity on kidney

There has been a major increase in obesity among children over the past twenty years. Obesity is associated with glomerular hyperperfusion and hyperfiltration from physiological (mal)adaptation resulting from afferent arteriolar vasodilatation. The renal injury from hyperfiltration in obesity is further exacerbated by concomitant presence of dyslipidemia, hyperglycemia and/or insulin resistance, inflammation and hypertension. The renal injury clinically manifests as microalbuminuria, proteinuria and/or poor renal function, and is histologically characterized by glomerulomegaly, mesangial expansion and/or sclerosis, which has been termed "obesity related glomerulopathy". Obesity portends a poor prognosis in subjects with chronic kidney diseases, IgA nephropathy and nephrectomy. Obese individuals on dialysis and renal transplant have mixed outcomes. The purpose of this review is to highlight the nondiabetic consequences of obesity on kidney for the pediatric nephrology community as we begin to address the obesity epidemic in children.
DISCOVERY OF A KIMBERLITE PIPE AND RECOGNITION OF A DIAGNOSTIC BOTANICAL INDICATOR IN NW LIBERIA

Diamond-bearing kimberlite dikes (fissures) are present in the deeply eroded Man Shield of West Africa. Small kimberlite pipes, generally less than 1 hectare in area, are known in Guinea, Sierra Leone, and Liberia. Exploration for larger bodies has been severely hampered by thick tropical vegetation, and the lack of distinct geophysical contrasts between weathered kimberlite and the nonresponsive nature of country-rock granites and granodioritic gneisses. Following several years of intense exploration in the highly active artisanal diamond district of northwestern Liberia (which was a major source of alluvial “blood diamonds”) by several large companies and the present study, we report that an elusive diamond-bearing kimberlite pipe has finally been located. A bonus to the pipe location is that an unusual botanical indicator, Pandanus candelabrum , is now recognized exclusively on the pipe and not in eluvium covering the adjacent kimberlite dikes. Plants ( Lychnis alpina ) have been widely used since medieval times for copper in Sweden, and with Haumaniastrum katangese, more recently in Africa. Other plants have evolved to physiologically stabilize heavy metals (U, Pb, Zn, Ni, Cr, Ba, Pb, Zn) in leaves and bark. Termite hills have been used in diamond exploration for kimberlitic indicator minerals (ilmenite, chromite, garnet, pyroxene) in Botswana, the United States, and Australia, but the identification of Pandanus candelabrum, with stilt-like aerial roots, is the first plant to be described that has a marked affinity for kimberlite pipes. This could dramatically change the exploration dynamics for diamonds in West Africa, as geobotanical mapping and sampling is cost-effective in tough terrain.
Minimally Invasive Surgery in Gynecologic Oncology

Minimally invasive surgery has been utilized in the field of obstetrics and gynecology as far back as the 1940s when culdoscopy was first introduced as a visualization tool. Gynecologists then began to employ minimally invasive surgery for adhesiolysis and obtaining biopsies but then expanded its use to include procedures such as tubal sterilization (Clyman (1963), L. E. Smale and M. L. Smale (1973), Thompson and Wheeless (1971), Peterson and Behrman (1971)). With advances in instrumentation, the first laparoscopic hysterectomy was successfully performed in 1989 by Reich et al. At the same time, minimally invasive surgery in gynecologic oncology was being developed alongside its benign counterpart. In the 1975s, Rosenoff et al. reported using peritoneoscopy for pretreatment evaluation in ovarian cancer, and Spinelli et al. reported on using laparoscopy for the staging of ovarian cancer. In 1993, Nichols used operative laparoscopy to perform pelvic lymphadenectomy in cervical cancer patients. The initial goals of minimally invasive surgery, not dissimilar to those of modern medicine, were to decrease the morbidity and mortality associated with surgery and therefore improve patient outcomes and patient satisfaction. This review will summarize the history and use of minimally invasive surgery in gynecologic oncology and also highlight new minimally invasive surgical approaches currently in development.
Organic and redox speciation of iron in the eastern tropical North Pacific suboxic zone

The organic and redox speciation of iron was examined in the strongly layered upper water column of the eastern tropical North Pacific, including oxic and suboxic waters, in a region 100–1300 km offshore. Suboxic conditions ([O2] < 5 μM) were found to affect the organic speciation of iron, and reduced dissolved iron, Fe(II), was present in the suboxic zone, but conditions were not sufficiently reducing to convert all iron to Fe(II). Dissolved iron concentrations in the suboxic zone were similar to concentrations found in oxic regions. Using a competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV) method, natural ligands were found to have distinct characteristics in the oxic and suboxic waters with stronger ligands found in the suboxic zone. It is unusual to find stronger ligands below the euphotic zone, but their strength, logKFe′L = 12.1–12.8, is within the range determined for surface ligands in other regions. These strong ligands may be the result of the unique chemistry of the suboxic zone stabilizing reduced or labile compounds, or they may be actively produced by microbes to enhance iron uptake. No onshore–offshore trends in ligand strength or concentration were detected suggesting the ligands may result from the inherent chemistry of the suboxic zone or production from denitrifiers, rather than the resident suboxic zone population of Prochlorococcus which were more abundant nearshore. A luminol-chemiluminescence based flow injection analysis (FIA) technique capable of detecting picomolar concentrations of Fe(II) was used to assess the redox state of iron in the suboxic zone and overlying oxic waters at a station 1300 km offshore. An elevated signal equivalent to 0.12–0.15 nM Fe(II), 21–24% of dissolved iron, was found only in the suboxic waters. Oxidation kinetics suggest that this Fe(II) is most likely produced by an in-situ process, as opposed to being transported from shelf sediment. The luminol-chemiluminescence Fe(II) method was systematically tested for inferences from reduced species potentially present in the suboxic zone to validate our Fe(II) results. Several species, V(IV) and V(III), produced significant signals, but considerations of the reducing state of the suboxic zone make it unlikely that reduced V is present. With additional information on the identity of the suboxic zone species provided by analysis of signal decay rate, it was determined that Fe(II) was the most reasonable source of the signal, and at minimum the chemiluminescence data allows us to set limits on the Fe(II) concentration in the offshore suboxic water column.
Characterization of Volatiles in Rambutan Fruit (Nephelium lappaceum L.)

The volatile compounds from the red-skinned cultivar of rambutan, Jitlee (Nephelium lappaceum L.), a tropical fruit native to Southeast Asia, were extracted using both Freon 113 and ethyl acetate s...
New (co)polymers by atom transfer radical polymerization

The fundamentals of atom transfer radical polymerization (ATRP) are presented. This includes the mechanistic considerations including structure of active and dormant species and structural features of the catalyst and reaction conditions as well as the nature of initiation and propagation steps. Extension of homogeneous polymerization to heterogeneous systems including emulsion polymerization is presented. Synthesis of (co)polymers with predefined molecular weights and low polydispersites as well as with controlled compositions, functionalities and architectures is reviewed.
The Yugoslav economic system

Abstract In his 1976 book, Horvat reviews the changes that have occurred in the Yugoslav economic system since 1945. Changes in policy, instruments used, and sectoral output are examined. Yugoslav policy makers are faulted for failing to understand the distinction between changes in the system and changes in policy instruments available under it. The consequence is economic instability. This review article considers the compatibility between market and socialism and provides some support for the Yugoslav interpretation of socialism, on the basis of the Constitution and of the Associated Labor Act.
Shakespeare's Skepticism Redefined

Critics have been busy tracing Shakespeare's apparent skepticism in individual plays and groups of plays. Skepticism, however, pervades the entire canon, in the sense that various plays are in antithetical relationships with each other, often as comic and tragic versions of the same themes (Richard III and The Taming of the Shrew, Romeo and Juliet and A Midsummer Night's Dream, King Lear and As You Like It, Othello and Much Ado About Nothing, Antony and Cleopatra and Troilus and Cressida). Such pairings suggest an unwillingness to be pinned down to any one reading of reality.
Dynamically generated follow-up questions

Automatic text generators are at the heart of systems that provide users with information. The trick is getting the system to answer follow-up questions as naturally as possible. We have devised a direct manipulation interface that treats system-generated texts as structured objects that users can manipulate. With our interface, users select the portions of system-generated text that they don't understand or want more information about, and the system provides a menu of questions to ask. Question menus, generated on the fly, take into account the user model, underlying knowledge base(s), and the prior discourse context.
Off-lattice NPT simulations of spherocylinder fluids

Abstract Thermodynamic properties of spherocylinder fluids in the absence of attractive interactions with length to diameter ratio of up to 15 have been determined by computer simulation. Properties that were studied include the isotropic-nematic transition, equation of state, and chemical potential. A constant temperature and pressure ensemble was used in the simulations. The spherocylinders were constrained to lie in one of three mutually perpendicular directions in continuous space. Good agreement was obtained between the computed thermodynamic properties and those predicted by scaled particle theory.
Is there a role for acetabular dysplasia correction in an asymptomatic patient

Background Childhood hip dysplasia is best treated in infancy or early childhood with hopes that the acetabulum will be completely normalized by nonoperative treatment methods, which may include Pavlik and brace treatment as well as formal closed reduction and hip spica casting. In many cases, this ideal result cannot be achieved and the child is left with residual dysplasia, which is often not symptomatic. Other patients may present late with hip dysplasia that is not identified in early childhood. Some develop hip pain with no prior known hip problem. Other children have asymptomatic dysplasia that is picked up on an incidental radiograph. The orthopaedic literature is clear regarding the need for corrective hip osteotomies in symptomatic children. Surgery to correct asymptomatic hip dysplasia remains controversial. Methods Children who have no symptoms yet have abnormal radiographs present a puzzling circumstance. In these cases, surgeons need to use quoted radiographic normal values for acetabular coverage of the femoral head as well as long-term natural history studies to decide whether to proceed with a corrective acetabular osteotomy. Long-term follow-up studies confirm that even patients with borderline dysplasia are likely to have significant hip symptoms and arthritis by middle age. Results Many children and adolescents with asymptomatic residual hip dysplasia should have corrective acetabular procedures performed. Surgery is more easily performed with more predictable results when the child is younger than 8 years. Conclusions It is impossible to state with certainty which children with residual radiographic hip dysplasia, but without symptoms, should have a corrective acetabular osteotomy. Review of the literature confirms that many patients have been undertreated in the past, with a high percentage of children with borderline hip dysplasia developing premature arthritis in early to mid-adult life. Current data suggest that surgery should be performed in borderline cases. Skill of the surgeon in performing acetabular osteotomies and/or ease of referral to a treatment center may temper the timing of such decisions.
Membrane lipid acyl group alterations in cells infected with a temperature-conditional mutant of Rous sarcoma virus.

Abstract The increased percentage of oleic acid and decreased percentage of arachidonic acid which occurs in the lipids of chicken emrbyo fibroblasts transformed by Rous sarcoma virus was shown to be transformation specific rather than a consequence of virus infection. Cells infected with a temperature conditional mutant of Rous sarcoma virus (RSV-T5) has a normal type fatty acid composition when held at the restrictive temperature of 41°C, but had a transformed type fatty acid composition when held at the permissive temperature of 36°C. However, these acyl group changes occurred slowly in the course of transformation, suggesting that they are not a primary event in the genesis of the transformed phenotype.
NEPTUNYL COMPOUNDS: POLYHEDRON GEOMETRIES, BOND-VALENCE PARAMETERS, AND STRUCTURAL HIERARCHY

The structures of 59 inorganic Np 5+ and Np 6+ neptunyl compounds are examined and placed within a structural hierarchy, with special attention to the relationships of these structures with U 6+ uranyl compounds. Forty-three Np 5+ neptunyl compounds containing square, pentagonal and hexagonal bipyramids have structural units consisting of isolated polyhedra (2), finite clusters of polyhedra (1), chains of polyhedra (12), sheets of polyhedra (16), and frameworks of polyhedra (12). Cation–cation interactions occur in 18 of these, resulting in a dramatic departure of their topologies from those of U 6+ uranyl compounds. Compounds with cation–cation interactions have structural units consisting of chains (4), sheets (4) and frameworks (10) of polyhedra. Those Np 5+ compounds that lack cation–cation interactions exhibit topologies that are similar or identical to those of U 6+ compounds. Sixteen Np 6+ neptunyl compounds have structural units consisting of isolated polyhedra (1), finite clusters of polyhedra (3), chains of polyhedra (4), and sheets (8) of polyhedra. None of these structures exhibit cation–cation interactions, and their topologies are similar to U 6+ uranyl compounds. Geometries of Np 5+ and Np 6+ polyhedra are examined, and updated bond-valence parameters, R o = 2.035 and b = 0.422, are provided for Np 5+ .
Intensity-modulated arc therapy: principles, technologies and clinical implementation

Intensity-modulated arc therapy (IMAT) was proposed by Yu (1995 Phys. Med. Biol. 40 1435-49) as an alternative to tomotherapy. Over more than a decade, much progress has been made. The advantages and limitations of the IMAT technique have also been better understood. In recent years, single-arc forms of IMAT have emerged and become commercially adopted. The leading example is the volumetric-modulated arc therapy (VMAT), a single-arc form of IMAT that delivers apertures of varying weights with a single-arc rotation that uses dose-rate variation of the treatment machine. With commercial implementation of VMAT, wide clinical adoption has quickly taken root. However, there remains a lack of general understanding for the planning of such arc treatments, as well as what delivery limitations and compromises are made. Commercial promotion and competition add further confusion for the end users. It is therefore necessary to provide a summary of this technology and some guidelines on its clinical implementation. The purpose of this review is to provide a summary of the works from the radiotherapy community that led to wide clinical adoption, and point out the issues that still remain, providing some perspective on its further developments. Because there has been vast experience in IMRT using multiple intensity-modulated fields, comparisons between IMAT and IMRT are also made in the review within the areas of planning, delivery and quality assurance.
Radiative exchange in a parallel-plate enclosure with translucent protective coatings on its walls

Abstract Thermal barrier and protective coatings are used for reducing temperatures in metal walls in high temperature applications, and for protection in corrosive environments. Radiative transfer is important at elevated temperatures, and hot coated surfaces that view each other can exchange radiation. Radiative exchange calculations are usually for surfaces that are opaque, and each surface has a specific radiating temperature. The analysis must be different when some or all of the surfaces have translucent coatings. Some protective coating materials such as zirconia and alumina, are partially transparent to portions of the thermal radiation spectrum. Hence, the radiative exchange process is more complex since radiation from a coated area depends on the temperatures within its coating. These temperatures are unknown, and they depend on the exchange process. The exchange analyzed here is for a parallel-plate enclosure that can have different heating conditions for the internal and external surfaces of each coated wall. Each wall has an opaque outer layer such as a metal plate, and a translucent coating on the inside. The coatings on opposite walls view each other and exchange radiation. An analytical method is developed for obtaining the temperature distribution in each coating and its opaque substrate. Illustrative results are provided for coatings with various optical thicknesses, and are compared with results for opaque coatings.
Phase singularities, correlation singularities, and conditions for complete destructive interference

A previously derived condition for the complete destructive interference of partially coherent light emerging from a trio of pinholes in an opaque screen is generalized to the case when the coherence properties of the field are asymmetric. It is shown by example that the interference condition is necessary, but not sufficient, and that the existence of complete destructive interference also depends on the intensity of light emerging from the pinholes and the system geometry; more general conditions for such interference are derived. The phase of the wave field exhibits both phase singularities and correlation singularities, and a number of nonintuitive situations in which complete destructive interference occurs are described and explained.
A fat-soluble material from plasma having the biological activities of biotin.

SummaryThe plasma of various species of animals yields, after hydrolysis with acids or enzymes, a fat-soluble material capable of replacing biotin in the growth of Lacto-bacillus casei and other lactic acid bacteria but not inactivated by avidin. When injected in chickens the material protected them from the injurious effects of a diet high in egg-white. Preparations containing the active material were found to be hemolytic, and in preliminary fractionations the growth and the hemolytic activities have gone together. The properties of the material do not correspond to those of oleic acid or of any previously described vitamers of biotin.
Influence of aggregate size on fracture toughness of concrete

Abstract Employing an extension of the splitting tensile by using a notched cylinder specimen, we have studied effects of initial notch length and maximum aggregate size on fracture toughness of concrete. Experimental results show that maximum aggregate size does influence ductility, with increasingly ductile behavior associated with increasing aggregate size. The results also support previous work in that initial notch length and maximum load do not yield a constant value for fracture toughness, whereas maximum linear load and initial notch length minimize the effects of slow crack growth and do produce a more constant value.
Optimal Overlay Construction on Heterogeneous Live Peer-to-Peer Streaming Systems

Media streaming is an important Internet application and has received more and more attention in recent years. Traditional media streaming systems are deployed in a server-client mode which scales poorly with the increasing population of the clients. Peer-to-peer media streaming can greatly enhance the scalability of the system by employing the clients to help forward the media content. In this paper, we consider optimizing the overlay construction for peer-to-peer streaming systems with heterogeneous access link bandwidths. Our goal is to maximize the total downloading rate and satisfy the heterogeneous downloading requirements when the uplink bandwidth is limited. We first formalize it into a problem of finding maximum number of edge disjoint trees in a graph which models the peers and their access link bandwidths. Then we give a centralized heuristic algorithm to solve the problem. Based on the centralized algorithm, we further propose a distributed algorithm which constructs an adaptive overlay topology that can adapt itself to the changing peers such that the end-to-end delay and link stress are minimized. We compare our scheme with another recently proposed scheme called MDM through simulations. Our simulation results show that the proposed scheme outperforms MDM by about 30% with respect to the average peer satisfaction. In addition, the proposed scheme achieves less link stress than MDM.
Prevention of Monocarpic Senescence in Soybeans with Auxin and Cytokinin: An Antidote for Self-Destruction

Foliar applications of alpha-naphthaleneacetic acid, together with 6-benzyladenine, prevent the seed-induced degeneration (monocarpic senescence) in soybeans. In addition to halting leaf yellowing and shedding, this treatment prevents the loss of starch and nitrogen that occurs during senescence of these leaves. Although nitrogen and starch are normally redistributed to support pod growth, pod development is not impaired by this treatment, apparently because photosynthesis and nitrogen assimilation continue.
Enhancement of gamma activity after selective activation of dopamine D4 receptors in freely moving rats and in a neurodevelopmental model of schizophrenia

Dopamine D4 receptor (D4R) mechanisms have been implicated in several psychiatric diseases, including schizophrenia, attention-deficit hyperactivity disorder (ADHD), and autism, which are characterized by cognitive deficits. The cellular mechanisms are poorly understood but impaired neuronal synchronization within cortical networks in the gamma frequency band has been proposed to contribute to these deficits. A D4R polymorphism was recently linked to variations in gamma power in both normal and ADHD subjects, and D4R activation was shown to enhance kainate-induced gamma oscillations in brain slices in vitro. The goal of this study was to investigate the effect of D4R activation on gamma oscillations in freely moving rats during natural behavior. Field potentials were recorded in the frontal, prefrontal, parietal, and occipital cortex and hippocampus. Gamma power was assessed before and after subcutaneous injection of a D4R agonist, A-412997, in several doses between 0.3 and 10.0 mg/kg. The experiments were also repeated in a neurodevelopmental model of schizophrenia, in which rats are prenatally treated with methylazoxymethanol (MAM). We found that the D4R agonist increased gamma power in all regions at short latency and lasted for ~2 h, both in normal and MAM-treated rats. The effect was dose dependent indicated by the significant difference between the effects after 3 and 10 mg/kg in pair-wise comparison, whereas 0.3 and 1.0 mg/kg injections were ineffective. This study demonstrates the involvement of D4R in cortical gamma oscillations in vivo and identifies this receptor as potential target for pharmacological treatment of cognitive deficits.
Synthesis, Structure Determination, and Hydrogen Sorption Studies of New Metal−Organic Frameworks Using Triazole and Naphthalenedicarboxylic Acid

Two new metal−organic framework compounds were synthesized under solvothermal conditions using Zn2+ ion, 1,2,4-triazole (TRZ), and 1,4- and 2,6-naphthalenedicarboxylic acids (NDC): Zn4(TRZ)4(1,4-NDC)2·2DMF·2H2O (1) and Zn4(TRZ)4(2,6-NDC)2·2DMF·4H2O (2). Their crystal structures were characterized by single-crystal X-ray diffraction. Structure 1 crystallizes in the P21/n space group with a = 13.609(2) A, b = 27.181(5) A, c = 13.617(3) A, β = 92.46(1) °, V = 5032.4(16) A3, and Z = 4. Structure 2 crystallizes in orthorhombic Pna21 space group with a = 30.978(6) A, b = 12.620(3) A, c = 13.339(3) A, V = 5215(2) A3, and Z = 4. Both structures are analogues of the previously reported Zn4(TRZ)4(1,4-BDC)2·16H2O where the layers of Zn−triazole moieties are pillared by aromatic dicarboxylates to create 3-D open frameworks. Nitrogen sorption studies revealed that these structures have Brunaer−Emmett−Teller (BET) surface areas of 362.1−584.1 m2/g. Hydrogen sorption experiments showed they can store 0.84−1.09 wt % of ...
Improved parametrization schemes for electronic energy bands

In connection with semiempirical studies of electronic band structures we consider the development of parametrization schemes based mainly on the logarithmic derivatives ${L}_{l}$ rather than exclusively on the tangent of the phase shifts, $tan{\ensuremath{\eta}}_{l}$, as was done in an earlier study. Improvements over the earlier approach are sought in two different approaches considered here for the noble metals. In the first of these the logarithmic derivatives of the radial wave functions are exclusively treated as the fundamental quantities to be parametrized. For a comparable number of parameters, this scheme gives a small over-all improvement in the accuracy of fit to the results of several first-principles band calculations as compared to the fit obtained in the earlier $tan{\ensuremath{\eta}}_{l}$ parametrization scheme. The second scheme gives significantly better fits to the first-principles band-calculation results. This approach obtains these improved results by adopting a hybrid technique which uses $tan{\ensuremath{\eta}}_{l}$ parametrization to treat the resonant part of the $d$ scattering contribution, while the residual $d$ scattering and the complete $s$ and $p$ contributions are treated by parametrizing the logarithmic derivatives. The parametrization of the smoothly varying logarithmic derivatives is done in a uniform and systematic way in terms of square-well potentials. A simplified version of this scheme is also successful for a "simple" metal as demonstrated by an application to Al. An advantage of both schemes in an empirical application is that the goodness of fit is rather insensitive to the energy values used in evaluating the parameters. Finally, we discuss the relative advantages of the present scheme over others that have been proposed.
Dispersion-engineered tapered planar waveguide for coherent supercontinuum generation

Abstract We have designed a tapered planar rib waveguide and numerically studied supercontinuum generation by the propagation of input pulses at 1.55 μm. The Air-SF57 glass-SiO 2 waveguide is 2 cm long, with a varying etch depth to manage the total dispersion. This proposed waveguide geometry significantly broadens the output spectrum caused by continuous modification of the phase matching condition for dispersive wave emission. The coherence property has also been investigated, demonstrating that fully coherent supercontinuum extending from ~1 μm to ~4.6 μm can be obtained with proper pumping conditions.
The Shifting Geography of Urban Education.

Poverty in the United States is migrating far beyond the urban core and transforming the suburbs into places increasingly stratified by income, wealth, opportunity, and education. Census data from the 2005 American Community Survey reveal new patterns of income inequality, residential mobility, and spatial segregation that make the suburbs less of a place apart and more like the rest of the United States. For the first time, a larger number of America’s poor are living in the suburbs than in the cities. This article describes the shifting geography of poverty in the metropolitan Atlanta area and how this trend relates to schools. Atlanta is a good location in which to observe the changing residential patterns of poor and working-poor families because the challenges facing suburban school systems in this Sunbelt city of more than 5 million can be read as a bellwether of major political, economic, and educational policy choices to come and the social context within which these choices will be decided.