cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnetic and spectral studies of some anomolous Mono-(2, 2′, 2″,-terpyridine) complexes of Co(II) and Ni(II)

Abstract Mono(2,2′,2″-terpyridine) complexes of formula M-(terpy)X 2 with M = Co(II), X = CN, NO 2 and F and with M = Ni(II),X = CN and SCN have been prepared. Their spectra in the visible, near infrared and infrared regions have been obtained. The magnetic behavior of these compounds has been studied over the range 15–400°K. These data indicate that the compounds are not five-coordinate but are cation-anion species involving in each case a bis(terpyridine) cation (with the exception of Ni(terpy)(SCN) 2 which contains bridging thiocyanate groups). The anions in the case of the two cyanides are shown to be the square planar M(CN) 4 2− . The (CoF 4 ) 2− anion is best interpreted as a tetrahedral ion. The evidence suggests that the anion in the nitrite compound involves a dimeric structure with bridging nitrite groups.
Effective actions for statistical data assimilation

Data assimilation is a problem in estimating the fixed parameters and state of a model of an observed dynamical system as it receives inputs from measurements passing information to the model. Using methods developed in statistical physics, we present effective actions and equations of motion for the mean orbits associated with the temporal development of a dynamical model when it has errors, there is uncertainty in its initial state, and it receives information from noisy measurements. If there are statistical dependences among errors in the measurements they can be included in this approach.
On the origin of non-linear breakage kinetics in dry milling ☆

Abstract While population balance models (PBMs) have described the impact of mechanical interparticle interactions on the specific breakage rate in dry milling processes through a phenomenological effectiveness factor, such models lack particle-scale information and thus a mechanistic basis. In this study, a mechanistic effectiveness factor of the non-linear PBM was derived and calculated by coupling a particle-scale breakage model with interparticle interactions obtained from discrete element method (DEM) simulations of a grinding ball impacting an unconfined particle bed. Mono, binary, ternary, and polydispersed particle beds were simulated to determine the effects of granular composition on breakage kinetics. The effectiveness factor obtained from the DEM simulations shows a reduction in the specific breakage rate for coarse particles in binary mixtures. The origin of this phenomenon, commonly known as cushioning or decelerated breakage in dry milling processes, was explained by the DEM simulations: fine particles in a particle bed increase mechanical energy loss, and reduce and distribute interparticle forces thereby inhibiting the breakage of the coarse component. On the other hand, the specific breakage rate of fine particles increased due to contacts associated with coarse particles. Such phenomenon, known as acceleration, was shown to be less significant, but should be considered in future attempts to accurately quantify non-linear breakage kinetics in the modeling of dry milling processes. The phenomenological effectiveness factor was also assessed and found to accurately describe the impact of mechanical interparticle interactions in binary particle beds as well as predict the non-linear breakage behavior in ternary and polydispersed particle beds. Aside from gaining particle-scale insight into non-linear breakage kinetics, the above findings provide the guidelines for the usage of non-linear PBM framework and are expected to improve the design, control, and optimization of dry milling processes that exhibit non-linear breakage kinetics.
Interactions of fluid oxygen drops in fluid hydrogen at rocket chamber pressures

A model of fluid drop behavior in clusters has been developed including the interactions induced by the drop proximity. The model is based upon the global conservation equations for the interstitial cluster region coupled to isolated fluid drop equations previously developed. Heat and mass transfer to the cluster are modeled using the Nusselt number concept. Results from calculations for the LO_x–H_2 system show the predictions to be insensitive to the value of the Nusselt number over three orders of magnitude. The results also show that at fixed pressure, increased drop proximity induces increased accumulation of LO_x in the interstitial space inside the cluster. At fixed initial drop proximity, the gradients of the dependent variables become increasingly smeared as the pressure increases; an opposite result from that obtained for isolated drops (Harstad K, Bellan J. Isolated fluid oxygen drop behavior in fluid hydrogen at rocket chamber pressure. Int J Heat Mass Transfer 1998; 41:3537–50). It is thus inferred that clusters of drops might be a desirable aspect in supercritical combustion because they aid interdiffusion of the reactive components.
Water Content-Density Criteria for Compacted Soil Liners

Soil liners have traditionally been compacted in the field to a minimum dry unit weight over a specified range in water content. This approach evolved from the practice for structural fills for which strength and compressibility are of primary concern. With soil liners, hydraulic conductivity is usually of paramount importance. Hence, the approach used to ensure adequate strength and permissible compressibility is not necessarily applicable to the construction of soil liners. Data are presented to show that the water content-density criteria for compacted soil liners can be formulated in a manner that is different from the approach currently used by many engineers. The recommended approach is based on defining water content-density requirements for a broad, but representative, range of compactive energy, and relating those requirements to hydraulic conductivity and other relevant factors. A case history illustrates the recommended procedure and its implementation. Hydraulic conductivity measurements were performed on three soils to develop an “acceptable zone” on the compaction curve that was used for quality control during construction. As a result of implementing the recommended procedure, construction operations were significantly accelerated.
Cyclic twin nucleation in tin-based solder alloys

Abstract The microstructure and Sn crystal orientations of lead-free solder alloys such as near-eutectic SnAgCu have a significant influence on the mechanical response of a solder joint to service conditions. Thus solidification processes were examined in SnAgCu solder joints. Distinct evidence of sixfold cyclic growth twinning of Sn during solidification from the melt was observed in Sn–Ag, SAC and Sn–Cu solders. Three orientations of Sn grains, each having a common 〈1 0 0〉 direction, were found in each of these systems, though the morphologies of these cyclic twinned microstructures differed. Analysis of dendrite arm spacing in cyclically twined structures with a beach ball morphology implies that the common 〈1 0 0〉 axis intersects with the region of the nucleation event. Models are presented for two pseudo/metastable hexagonal unit cells based upon {1 0 1} or {3 0 1} twins that introduce the cyclic twinning structure at the nucleation stage. Formation of these hexagonal unit cells may be facilitated by the presence of alloy elements. Subsequent epitaxial growth of the tetragonal unit cell on this nucleus can account for all three types of morphologies observed in microstructures of Sn-rich solder alloys.
Scalable State Management for Scientific Applications in the Cloud

The data generated by scientific simulations and experimental facilities is beginning to revolutionize the infrastructure support needed by these applications. The on-demand aspect and flexibility of cloud computing environments makes it an attractive platform for data-intensive scientific applications. However, cloud computing poses unique challenges for these applications. For example, cloud computing environments are heterogeneous, dynamic and non-persistent which can make reproducibility a challenge. The volume, velocity, variety, veracity and value of data combined with the characteristics of cloud environment make it important to track the state of execution data and application's entire lifetime information to understand and ensure reproducibility. This paper proposes and implements a state management system (FRIEDA-State) for high-throughput and data-intensive scientific applications running in cloud environments. Our design addresses the challenges of state management in cloud environments and offers various configurations. Our implementation is built on top of FRIEDA (Flexible Robust Intelligent Elastic Data Management), a data management and execution framework for cloud environments. Our experiment results on two cloud test beds (FutureGrid and Amazon) show that the proposed solution has a minimal overhead (1.2ms/operation at a scale of 64 virtual machines) and is suitable for state management in cloud environments.
Expase-and-merge exploration and the chromatic number of a random graph

The expose-and-merge paradigm for exploring random graphs is presented. An algorithm of complexityn O(logn) is described and used to show that the chromatic number of a random graph for any edge probability 0<p<1 falls in the interval $$\left[ {\left( {\frac{1}{2} - \varepsilon } \right)\log (1/(1 - p))\frac{n}{{\log n}}, \left( {\frac{2}{3} + \varepsilon } \right)\log (1/(1 - p))\frac{n}{{\log n}}} \right]$$ with probability approaching unity asn→∞.
Thyroidal content of thyrocalcitonin in hypothyroid and hyperthyroid rats.

The thyrocalcitonin content of the thyroid glands of euthyroid, hyperthyroid and hypothyroid rats fed a calcium deficient diet was determined in 2 separate experiments by bioassay. Hyperthyroidism was produced by the injection of 50 μg l-thyroxine or 200 mU thyrotropin per day, and hypothyroidism by the dietary administration of 0.05% propylthiouracil or an iodine deficient diet. The log-dose response curve for the hypocalcemic activity of the thyroid homogenates from the euthyroid rats was linear between 0.24 and 0.96 mg thyroid tissue, equivalent to 0.018–0.072 of a single rat thyroid gland. No significant differences in the hypocalcemic response of assay rats was observed when a comparison was made of thyroid tissue homogenates that included parathyroid tissue and thyroid homogenates in which the parathyroid gland was removed prior to tissue homogenization. Thyroxine consistently caused a significant 27–35% reduction in the thyroidal content of thyrocalcitonin, whereas the administration of thyrotropin...
On the cholesteryl ester hydrolase activity in the microsomal and supernatant fractions of pigeon aorta.

Abstract Cholesteryl ester hydrolase activity was measured in the microsomal and supernatant fractions of the aorta of atherosclerosis-susceptible White Carneau and atherosclerosis-resistant Show Racer pigeons while on their normal cholesterol-free diets. Enzyme activities from both fractions showed fatty acid specificities for the hydrolysis of different Cholesteryl esters in the following decreasing order: Linoleate > oleate > palmitate. At 9 months of age (the period of lipid accumulation) the microsomal enzyme activity in the Show Racer breed was significantly higher ( P P
Mirror, Mirror on the Wall: Enhancement in Self-Recognition

People's inferences about their own traits and abilities are often enhancing. A series of experiments suggests that this enhancement extends to more automatic and perceptual judgments as well, such that people recognize their own faces as being more physically attractive than they actually are. In each experiment, participants' faces were made more or less attractive using a morphing procedure. Participants were more likely to recognize an attractively enhanced version of their own face out of a lineup as their own, and they identified an attractively enhanced version of their face more quickly in a lineup of distracter faces. This enhancement bias occurred for both one's own face and a friend's face but not for a relative stranger's face. Such enhancement was correlated with implicit measures of self-worth but not with explicit measures, consistent with this variety of enhancement being a relatively automatic rather than deliberative process.
A high-frequency sparker source for the borehole environment

For tomographic investigations of shallow subsurface features of limited lateral extent, a high‐frequency, low‐cost borehole seismic source would be highly desirable, particularly for investigators with limited budgets. We constructed a simple, arc‐discharge seismic source from off‐the‐shelf items. This source consists of a salt water filled bottle containing exposed conductors of a coaxial cable, across which 100 to 300 joules of electrical power were discharged. This source produced a seismic pulse with a dominant frequency in the neighborhood of 1.5 kHz and a half‐power bandwidth in excess of 1 kHz. Repeatability of seismic signatures in a variety of environmental settings was excellent. Sufficient power was generated to observe seismic signals with at least a 35 dB signal‐to‐noise ratio at horizontal borehole separations of 100 m. For a borehole separation of 33.2 m, signals with at least a 35 dB signal‐to‐noise ratio were observed at angular ranges in the vertical plane to 68 degrees. The hydrostatic...
Phase equilibrium in nearly monodisperse fluids

Abstract The two-phase equilibrium and critical point conditions of a polydisperse fluid (a mixture with a continuous distribution of components) are solved by making power-series expansions about the properties of a single representative species.
Total emissivity of hot water vapor—I. High pressure limit

Abstract Recent measurements of the infrared spectral emissivity of hot water vapor at temperatures between 1000°K and 2250°K are used to determine the total emissivity of H2O. In this work the total emissivity is determined (1) exactly for the experimental conditions at which the measurements were made and (2) in an approximation which provides an upper limit to the emissivity for optical depths other than those of the measurements. The first determination yields results which agree quite well with the values of total emissivity given at the same conditions by Hottel. The upper-limit values of the second determination are expected to be approached by the true emissivity at high temperatures and pressures. Some brief comparisons are presented with other predictions of the total emissivity of water vapor under these conditions.
Kinematics of bipedalism in Propithecus verreauxi

Bipedalism is rare in primates and has evolved in two distantly related groups: hominoids and indrids. Although copious data are available on the mechanics of bipedal locomotion in hominoids and vertical clinging and leaping (VCL) in indrids, no research has addressed the unique mode of bipedal locomotion exhibited by select indrid primates. Propithecus verreauxi is a highly specialized indrid vertical clinger and leaper that uses a peculiar form of bipedalism on the ground. The objectives of this study were to describe the bipedal gait of Propithecus, to assess the influence of VCL specializations on the kinematic patterns and propulsion mechanisms used by Propithecus during bipedalism, and to compare Propithecus bipedalism with the bipedal gaits of other primates capable of using bipedalism. Video was collected of five adult P. verreauxi moving bipedally in a seminatural setting at the Duke University Primate Center. Duty factor, footfall patterns, joint angles and center of mass movement were quantified in the sagittal plane for 73 steps. Propithecus uses a bipedal gallop, a gait unique to Propithecus. The kinematic similarities (e.g. large hip and knee angular excursions and preparatory countermovements) between bipedal galloping and VCL lead us to suggest that Propithecus takes advantage of specializations for VCL to conserve energy during bipedal galloping. Propithecus also walks bipedally at slower speeds. When Propithecus walks, it utilizes a relatively compliant gait similar to that of other primate facultative bipeds (Pan, Hylobates). During bipedal walking, energy conservation may be sacrificed for increased balance and reduced joint loads.
Effect of p-aminobenzoic acid when added to purified chick diets deficient in unknown vitamins.

Summaryp-Aminobenzoic acid at levels of 5 to 15 mg per 100 g of diet produces growth responses in chicks receiving purified rations low in the unknown vitamins but complete in all other respects. Evidence is given however to suggest that p-aminobenzoic acid is not a specific growth factor for the chick but may act indirectly by stimulating intestinal microarganisms to produce unknown factor(s) essential for the chick. We are indebted to Nerck and Company, Raliway, K.J., for the crystalline vitamins; to Wilson Laboratories, Chicago, Ill., for solubilized Liver (liver fraction L), and whole liver substance; to TT'ilson and Co., Inc., Chicago, Ill., for gelatin; and to Allied Ells, Inc., Peoria, Ill., for soy bean oil. We are grateful to Mr. L. J. Teply and Mr. J. 0. Lampen for the p-aminobenzoic acid assays.
A solution for the MX/G/1-PS process response time

This paper describes an exact analysis of the M^X/G/1-PS process response time assuming multiple process classes. In the analysis we assume an egalitarian processor-sharing discipline with each process class m composed of m tasks. The task service time distributions are assumed to be general. Finally, the results given are significant since they represent a novel method for the analysis of parallel programs on processor-sharing systems.
The Gendering of Philippine International Labor Migration

This paper provides an institutional analysis of the use of gender as an organizing principle for labor migration flows. Through a case study of the marketing and recruitment strategies of Philippine government and private institutions, I examine how gendered representations contribute to divergent patterns of male and female labor migrants from the Philippines. Representations, or controlling images, are used by institutions to provide explanations or justification of a policy. Findings indicate that the global marketing of workers is organized around specific gendered assumptions of male versus female occupations. Recruitment strategies are also influenced by gendered representations of occupations, locations, and workers. The use of gender by government and private institutions as an organizing device provides a gendered context in which migrants and their households must subsequently operate.
Theoretical study of silicon dicarbide

Silicon dicarbide was first observed in 1926 in spectra of cool carbon stars. The carrier of these bands around 5000 A was tentatively identified as SiC2 by Kleman (1956) who produced similar spectra by inserting silicon into the graphite tube of a King furnace heated to over 2500 K. This identification was strengthened by subsequent mass spectral studies which showed SiC2 as a major molecular component of vaporized silicon carbide. The present investigation is concerned with calculations which were initiated in an attempt to understand more recent astronomical observations of unidentified lines in the millimeter-wave region of the spectrum. The calculations were designed to determine the ground state equilibrium structure and to obtain vibrational and rotational constants. Calculations for estimating the positions and structure of low-lying electronic states were also performed. Self-consistent field (SCF) calculations were performed assuming a closed-shell electronic structure analogous to that in C3. Calculations were conducted for symmetric CSiC, and asymmetric SiCC forms.
THE ETIOLOGY OF VERRUGA PERUANA.

A saline suspension of a subcutaneous nodule excised from a verruga patient, and kept in the refrigerator for 14 days, on inoculation into two young Macacus rhesus monkeys (Nos. 33 and 34) induced irregular febrile reactions and enlargement of the lymph glands, and in one instance a subcutaneous nodule arose, independently of direct inoculation, on the tail. A microorganism has been isolated from the blood of both animals, and from the experimental nodule, which in pathogenic properties and in cultural and morphological characteristics is indistinguishable from the strain of Bartonella bacilliformis isolated from a case of Oroya fever. The spontaneous skin lesion of Monkey 34 and the subcutaneous nodules induced by intradermal inoculation of cultures of the microorganism were histologically typical of experimental verruga lesions in monkeys and identical with the skin lesions induced in monkeys by Bartonella bacilliformis . The organism, like Bartonella bacilliformis , is an intracellular parasite, being found in the cytoplasm of the proliferating endothelial cells of the lesions and in the erythrocytes of the blood. The same variations in the manifestations of disease which have been noted in experimental infection with Bartmetta bacilliformis were observed in the experimental verruga infection. In the second passage (Monkey 41) the infection induced by local inoculation of cultures was severe both locally and constitutionally and was accompanied by marked anemia. The organisms were found in the red cells in large numbers. In the third passage the systemic infection was less severe, but the local lesions were more striking. Detection of the parasites in the blood is far more certain by the cultural method than by microscopic examination, the latter procedure being successful only in rather severe infections. The result of blood culture is therefore the decisive method in the final diagnosis of the disease. Preliminary serological study shows that the organism isolated in the present instance from the skin lesion of a verruga patient and that previously obtained from the blood of a case of Oroya fever belong to the same serological group. The data obtained justify the conclusion that verruga peruana is caused by Bartonella bacilliformis . They also definitely establish the fact that the inoculation of blood or sanguineous exudate from lesions of verruga peruana is capable of inducing in susceptible individuals a severe febrile systemic infection, such as that to which Carrion succumbed. The designation "Carrion's disease" is therefore the appropriate one for both forms of the infection. Bartonella bacilliformis may be regarded as a bacterium, since it has the essential features of that group of microorganisms.
Experimental study of temperature and CH radical location in partially premixed CH4/air coflow flames

Abstract As part of an ongoing investigation of an exhaust NOx emission index minimum measured for partially premixed flames, radial temperature profiles and CH radical locations were measured in atmospheric-pressure, partially premixed, coflow, methane/air flames with fuel-side equivalence ratios of 1.6, 2.0, and 3.5, at three axial heights above the burner. The work was undertaken because of the importance of temperature and CH radical behavior in NO formation chemistry. Thin-filament pyrometry was found to be more appropriate than thermocouple thermometry for temperature measurements in partially premixed flames. Results demonstrated that the 1.6-equivalence-ratio flame exhibited classical double-flame structure, the 2.0-equivalence-ratio flame was a merged flame, and the 3.5-equivalence-ratio flame exhibited diffusion-flame structure. Signals from CH∗ chemiluminescence and CH laser-induced fluorescence provide evidence that, for the present measurement locations, double flames exhibit single CH peaks which can be associated with their premixed component flames. Double CH radical peaks, which were predicted to occur in low-strain-rate flames, were not found for the limited number of flame conditions and locations studied. In the near-burner region, the premixed and nonpremixed component flames of the ΦB = 1.6 double flame diverge radially with increasing downstream distance and merge together for larger values of ΦB.
Test and measurement of SAW devices. A technology overview

The new generation of surface-acoustic-wave devices now available is opening up several new application areas. But, such is their speed and complexity, they are creating their own problems requiring accurate sophisticated test instruments
Corrugation of Chemically Converted Graphene Monolayers on SiO2

Sheets of chemically converted graphene (CCG) on the surface of Si/SiO2 substrates exhibit nanoscopic corrugation. This corrugation has been assumed to be caused by a combination of factors including (a) thermal treatments in the device preparation, (b) different oxygen-containing addends on the CCG, and (c) the substrate roughness. In this paper, we study the interplay of these factors in the corrugation behavior of monolayer CCG flakes, prepared by reduction of graphene oxide (GO) synthesized by Hummers method, and CCG nanoribbons, produced by chemical unzipping of carbon nanotubes, followed by the reduction by hydrazine at 95 °C. We have studied the morphology, composition, and electrical properties of the flakes and nanoribbons before and after annealing in Ar/H2 at 300 °C. Our experiments demonstrate that, despite the temperature treatment and the associated removal of the oxygen-containing addends from the basal plane of the CCG, the corrugation pattern of the CCG exhibits almost no change upon anne...
Terrain acquisition algorithm for an autonomous mobile robot with finite-range sensors

This paper presents a terrain model acquisition algorithm for a mobile robot with finite-range sensors in planar terrains. The finite two- dimensional terrain is populated by a finite number of stationary polygonal obstacles. If the robot can see only partial obstacle edge(s) because of its limited range of visibility, our algorithm guides the robot toward the direction in which the incomplete edge of the obstacle is completed at the end vertex. If the robot can see nothing at all within the current range, it is guided in a spiral-like manner to search the terrain for obstacles. In this paper, we formally describe this algorithm and show how it performs with respect to travel distance and the number of scanning operations for various sensor ranges. Also, some examples are shown.
Synthesis of polythienylenevinylene copolymers bearing carbondithioate structures

Abstract A new type of thiophene-based copolymers bearing the carbondithioate groups were synthesized through Wittig–Horner reaction. Copolymers were characterized by elemental analysis, UV–Vis, and FT-IR. Conductivity of I2 doped copolymers ranges from 10−3 to 10−2 S/cm.
Infinite subharmonic bifurcation in an SEIR epidemic model

The existence of both periodic and aperiodic behavior in recurrent epidemics is now well-documented. In this paper, it is proven that for epidemic models that incur permanent immunity with seasonal variations in the contact rate, there exists an infinite number of stable subharmonic solutions. Random effects in the environment could perturb the state of the dynamics from the domain of attraction from one subharmonic to another, thus producing aperiodic levels of incidence.
Liquid chromatographic determination of guanethidine salts and hydrochlorothiazide using electrochemical detection and ion-pair techniques.

A high-performance liquid chromatographic method with amperometric detection utilizing oxidation at the glassy carbon electrode is reported for the quantitative determination of a guanethidine (1)-hydrochlorothiazide (2) mixture. The drug mix is difficult to analyze by a single assay procedure due to large differences in the chemistry and chemical structure of the compounds. The drugs are best separated on an octadecylsilane column using 30:70 acetonitrile:0.05 M aqueous sodium dihydrogen phosphate containing 0.02 M sodium pentanesulfonate (pH 2.5) as the mobile phase at a 1.0 mL/min flow rate. Using a cell potential of + 1300 mV versus Ag/AgCI and procaine hydrochloride as the internal standard, calibration curves were established for 1 monosulfate or sulfate and 2 in the 0.5–10 and 1.25–25 μg/mL range, respectively. Accuracy and precision of the assay are in the 1.7–6% range. The procedure is shown applicable to the analysis of a combination dosage form and is also useful for either drug in a single component dosage form.
The paleomagnetism of two Aegean deep-sea cores

Abstract Two cores from the Aegean Sea were continuously sampled for paleomagnetic measurements. Sedimentation rates of 75.5 cm/1000 yr (V10-50) and 18.2 cm/1000 yr (V10-58) were derived from 14 C dates of sapropelic mud and ash layers, one of which, the Santorini ash, was present in both cores and was used for correlation. Most of the sediment in each core consisted of calcareous lutite of probable detrital origin. The magnetism of the cores was due to fine-grained magnetite, also of probable detrital origin and uniformly distributed in the lutite. For the total time represented by these cores (27 000 yr) all the samples were normally magnetized. The average inclination corresponded to that of an axial dipole. A cyclic fluctuation in inclination with an approximate period of 6000 yr is thought to be associated with anticlockwise precession of the dipole axis around the rotation axis. Another smaller fluctuation with period around 1000 yr is probably due to westward drift of the non-dipole field. The intensity data were in general agreement with trends established by archeomagnetic investigators.
Micro-optical crossconnect switch

A novel micro-optical crossconnect switch based on the use of diffractive optical elements is introduced. A set of micro-actuated diffractive optical elements are used to reshape the optical beam as well as establish the interconnection required between two arrays of input and output optical fibers. The coupling efficiency of the switch is shown to be far higher than those using reflecting mirrors. Possible techniques for the fabrication of the switch are discussed.
Stress concentration due to an array or hemispherical cavities at the surface of an elastic half-space

The paper investigates the perturbation in an otherwise uniform stress field in an elastic half-space due to a doubly-periodic array of small hemispherical holes at the free surface. The solution is obtained using three potential functions of double Fourier series form in Galerkin's strain potential solution, the coefficients of which are determined using the collocation method. The unperturbed field is taken to be one of uniform plane stress parallel to the free surface. Two special cases are studied—uniform tension and uniform shear stress. Numerical results for these cases can be generalized by superposition to give solutions for a general state of biaxial plane stress. It is found that, for both tension and shear, the maximum stress concentration occurs at the bottom of the holes. The stress concentration factor increases with the ratio of hole spacing to radius, approaching the known solution for a single hemispherical hole at large ratios.
Eating disorder and affective disorder: Relatives or merely chance acquaintances?

Abstract Evidence is reviewed suggesting that more than a chance relationship exists between affective (depressive) disorder and eating disorder. Despite occasional glaring exceptions, findings from clinical, outcome, family, medication response, and biological studies of persons with anorexia nervosa or bulimia are strikingly consistent in indicating the presence of a subgroup (but only a subgroup) characterized also by depressive disorder, whether as antecedent, concomitant, or consequence of the eating disorder. Different models are proposed that could account for this relationship and it is postulated that all of these may actually be relevant.
Early onset mandibuloacral dysplasia due to compound heterozygous mutations in ZMPSTE24

Mandibuloacral dysplasia (MAD) is an autosomal recessive disorder characterized by hypoplasia of the mandible and clavicles, acro-osteolysis, and lipodystrophy due to mutations in LMNA or ZMPSTE24. Only six MAD patients are reported so far with ZMPSTE24 mutations and limited phenotypic data are available for them. Here, we report on two brothers (4 years and 9-month old) with early onset MAD due to ZMPSTE24 mutations in whom thin skin was noted as early as 5 months of age. Both had micrognathia, mottled hyperpigmentation, and enlarged fontanelles but little evidence of lipodystrophy. There was no delay of mental development. The older brother had small pinched nose, short clavicles, acro-osteolysis, stunted growth, joint stiffness, and repeated fractures. There was no evidence of renal disease. Both patients were compound heterozygotes harboring a previously reported missense ZMPSTE24 mutation, p.Pro248Leu, and a novel null mutation, p.Trp450stop. These patients and the review of literature reveal that compared to MAD patients with LMNA mutations, those with ZMPSTE24 mutations develop manifestations earlier in life. Other distinguishing features in MAD due to ZMPSTE24 mutations may include premature birth, renal disease, calcified skin nodules, and lack of acanthosis nigricans. We conclude that in patients with MAD due to ZMPSTE24 mutations, the onset of disease manifestations such as thin skin and micrognathia occurs as early as 5 months of age. In these patients, skeletal phenotype presents earlier whereas lipodystrophy and renal disease may occur later in life.
Polyphenolic profiles detected in the ripe berries of Vitis vinifera germplasm

Polyphenolic profiles in the berry samples of 344 European grape (Vitis vinifera) cultivars were evaluated for two consecutive years. These cultivars represent a diverse collection of V. vinifera germplasm maintained at the USDA-Agricultural Research Service Vitis Clonal Repository in Davis of California, USA. A total of 36 polyphenolic compounds, including 16 anthocyanins, 6 flavonols, 6 flavanols, 6 hydroxycinnamic acids and 2 hydroxybenzoic acids, were identified via HPLC-MS and quantified by HPLC-DAD. The mean contents for anthocyanins, flavanols, flavonols, hydroxycinnamic acids and hydroxybenzoic acids were 0.946 (coloured cultivars), 0.147, 0.043, 0.195 and 0.016mgg(-1) FW, respectively. On average, wine grapes had higher concentrations than had table grapes for all of these compounds except hydroxycinnamic acids. Berry colours affected the total contents of anthocyanins, but not others. Positive correlations (0.151-0.535) were found among these groups of compounds. As expected, these groups of compounds were all negatively correlated with berry weight.
Recommendations on the use of alcohols for preservation of ant specimens (Hymenoptera, Formicidae)

Collectors use a variety of concentrations and types of alcohols to preserve ant specimens. We evaluated existing literature, experimental evidence, and expert myrmecological advice to determine what kind and concentration of alcohol will result in the best preserved specimens for card-point mounting and DNA extraction. For our experimental evaluation, we killed and stored Solenopsis invicta, Camponotus floridanus, and Dorymyrmex bureni workers in isopropanol and ethanol at four concentrations (70, 85, 95, 100%) over three time periods (24 h, 1 month, 6 months). We then compared specimen condition and amenability to manipulation for mounting on card points. Specimens stored in either 95% isopropanol or 95% ethanol for time periods longer than 24 h produced the best specimens for mounting. A literature review revealed that DNA is best preserved in 95–100% ethanol due to the ability of ethanol to more rapidly penetrate cellular membranes and deactivate DNase activity than other primary alcohols. We recommend that general collections of adult ant specimens should be killed and stored in 95% ethanol. Following this recommendation will result in ant specimens that are easier to mount for museum collections and better preserved for molecular studies. A variety of other killing and preservation techniques relevant to the study of ants are also discussed.
Force Fluctuations Impact Genome Processing Kinetics

The current view of force-dependent enzyme kinetics neglects the role of fluctuations in the force, which are prevalent in all living cells due to thermal noise and active processes. Our calculations indicate that these fluctuations can qualitatively alter the dynamics of vital biomolecular processes, including transcription and supercoiling maintenance. As an illustrative example, we model the pausing of RNA polymerase as it transcribes through a nucleosome, demonstrating the importance of transient excursions to high forces exerted by fluctuations in wrapping of downstream DNA. We find that fluctuation timescales play a key role in setting overall transition rates and determinining the force regime of relevance. In addition, we consider the maintenance of DNA supercoiling by topoisomerase enzymes acting in a torsion-dependent manner. Using a basic kinetic model incorporating discrete torsion fluctuations and volatile obstacles, we show a nontrivial dependence of the equilibrium supercoil density on the length of DNA accessible for twist propagation. Our results demonstrate that accounting for force fluctuations is essential to developing a quantitative understanding of enzyme kinetics in the dynamic environment of a living cell.
Using extracted features to inform alignment-driven design ideas in an educational game

As educational games have become a larger field of study, there has been a growing need for analytic methods that can be used to assess game design and inform iteration. While much previous work has focused on the measurement of student engagement or learning at a gross level, we argue that new methods are necessary for measuring the alignment of a game to its target learning goals at an appropriate level of detail to inform design decisions. We present a novel technique that we have employed to examine alignment in an open-ended educational game. The approach is based on examining how the game reacts to representative student solutions that do and do not obey target principles. We demonstrate this method using real student data and discuss how redesign might be informed by these techniques.
Exposure to brand-specific cigarette advertising in magazines and its impact on youth smoking

Abstract Background. Despite the potential influence of cigarette advertising on youth smoking, few studies have characterized brand-specific magazine advertising exposure among youths or examined its impact on youth smoking behavior. Methods. A longitudinal youth survey was conducted to assess baseline exposure to brand-specific cigarette advertising in magazines and to measure subsequent smoking behavior. The sample comprised 1,069 Massachusetts youths, ages 12–15 years at baseline in 1993, and 627 of these youths who were interviewed after 4 years. Results. Five brands accounted for 81.8% of the gross impressions for magazine advertising among Massachusetts youths. These same brands accounted for 88.4% of the brand market share among 12- to 15-year-old smokers nationally in 1993. The levels of brand-specific advertising exposure in the sample were highly correlated with these national brand market shares ( r = 0.96, P = 0.0002). Among the cohort, baseline brand-specific exposure to cigarette advertising in magazines was highly correlated with brand of initiation among new smokers ( r = 0.93, P = 0.0001), brand smoked by current smokers ( r = 0.86, P = 0.0004), and brand whose advertisements attracted attention the most ( r = 0.87, P = 0.0002). Conclusion. By documenting a relationship between brand-specific magazine advertising exposure and brand of smoking initiation among new smokers, this study provides strong new evidence that cigarette advertising influences youth smoking.
Extremal functions of excluded tensor products of permutation matrices

For a 0-1 matrix Q, ex(n,Q) is the maximum number of 1s in an nxn 0-1 matrix of which no submatrix majorizes Q. We show that if P is a permutation matrix and Q is arbitrary, then the order of growth of ex(n,P@?Q) is almost the same as that of ex(n,Q), extending a result used in Marcus and Tardos's proof of the Stanley-Wilf conjecture.
Magnetic relaxation in generalized critical state model

Abstract Calculations of magnetic relaxation have been carried out, based on generalized critical state and flux creep models. The calculated relaxation rate as a function of the field is in good agreement with experimental data in high- T c superconductors. Also discussed are the critical state model, the flux pinning, and the field dependence of the magnetic relaxation.
A model predictive formulation for control of open-loop unstable cascade systems

Abstract Cascade control is commonly used in the operation of chemical processes to reject disturbances that have a rapid effect on a secondary measured state, before the primary measured variable is affected. In this paper, we develop a state estimation-based model predictive control approach that has the same general philosophy of cascade control (taking advantage of secondary measurements to aid disturbance rejection), with the additional advantage of the constraint handling capability of model predictive control (MPC). State estimation is achieved by using a Kalman filter and appending modeled disturbances as augmented states to the original system model. The example application is an open-loop unstable jacketed exothermic chemical reactor, where the jacket temperature is used as a secondary measurement in order to infer disturbances in jacket feed temperature and/or reactor feed flow rate. The MPC-based cascade strategy yields significantly better performance than classical cascade control when operating close to constraints on the jacket flow rate.
Interaction-free all-optical switching via the quantum Zeno effect

We propose an interaction-free scheme for all-optical switching which does not rely on the physical coupling between signal and control waves. The interaction-free nature of the scheme allows it to overcome the fundamental photon-loss limit imposed by the signal-pump coupling. The same phenomenon protects photonic-signal states from decoherence, making devices based on this scheme suitable for quantum applications. Focusing on {chi}{sup (2)} waveguides, we provide device designs for traveling-wave and Fabry-Perot switches. In both designs, the performance is optimal when the signal switching is induced by coherent dynamical evolution. In contrast, when the switching is induced by a rapid dissipation channel, it is less efficient.
Effects of community size and contact rate in synchronous social q&a

Social question-and-answer (Q&A) involves the location of answers to questions through communication with people. Social Q&A systems, such as mailing lists and Web forums are popular, but their asynchronous nature can lead to high answer latency. Synchronous Q&A systems facilitate real-time dialog, usually via instant messaging, but face challenges with interruption costs and the availability of knowledgeable answerers at question time. We ran a longitudinal study of a synchronous social Q&A system to investigate the effects of the rate with which potential answerers were contacted (trading off time-to-answer against interruption cost) and community size (varying total number of members). We found important differences in subjective and objective measures of system performance with these variations. Our findings help us understand the costs and benefits of varying contact rate and community size in synchronous social Q&A, and inform system design for social Q&A.
The development of integrated terrestrial and marine pathways in the Argo-Saronic region, Greece

Least cost path applications can be a powerful tool for understanding connectivity across a landscape. A limitation to this method is its difficulty in integrating terrestrial, marine, and cultural factors – all of which would have been at play in the prehistoric Aegean. This study looks at a method of modeling pathways that integrates major factors (land, sea, and culture) that would be in play while considering medium- to long-distance travel in the Aegean. This test case explores the possible relationships between proposed routes for communication and identified coastal sites with parameters modeled in geographic information system that affect travel in cultural, marine, and terrestrial contexts. The methods presented have significance beyond the Late Bronze Age Aegean. The development of a methodology that incorporates marine, cultural, and terrestrial environments provides a mechanism by which specific hypotheses regarding complex communication routes may be addressed in regions of the world where th...
Accuracy of the Born approximation in calculating the scattering coefficient of biological continuous random media

A rigorous error analysis is presented for the scattering coefficient of biological random continuous media in the Born (or single-scattering) approximation. The analysis is done in two dimensions (2-D) for simplicity of numerical computation. Scattering coefficients of various tissue-like random media are numerically calculated via statistical finite-difference-time-domain analysis. The results are then checked against analytical formulas for the scattering coefficient in the Born approximation. The validity ranges for the correlation length and the refractive index fluctuation strength of the medium are clearly identified. These 2-D results show promise for future 3-D investigations.
The role of positron emission tomography in the evaluation of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease that affects the gastrointestinal tract. Information obtained from a clinical history, physical exam, laboratory testing, imaging studies, and endoscopic evaluations must be combined to accurately diagnose IBD. Further testing often becomes necessary to evaluate symptom relapse in patients with an established IBD diagnosis. Endoscopy, while effective in assessing mucosal disease, is invasive and associated with inherent risks. Positron emission tomography (PET) is an effective, noninvasive tool for the evaluation of active inflammation. This review will focus on the role of PET imaging in the evaluation and management of IBD.
Soy Protein and Cardiovascular Disease: the Impact of Bioactive Components in Soy

Soy protein, when substituted for animal protein in the diet, will lower blood cholesterol. Recent research also provides evidence that soy protein and/or isoflavones may improve endothelial functioning and attenuate events leading to both lesion and thrombus formation.
Is the cure the poison? The evolving story of therapy-related myeloid malignancies.

In this issue of Leukemia and Lymphoma, Chen and colleagues perform a comparative analysis of presenting characteristics and outcomes of patients who develop myelodysplastic syndromes (MDS) or acut...
Calcium Supplementation: Is Protecting Against Osteoporosis Counter to Protecting against Cardiovascular Disease?

Calcium is the dominant mineral in bone and is a shortfall nutrient in the diet. For those consuming inadequate dietary calcium, calcium supplements have been a standard strategy for prevention of osteoporosis. Recently, calcium supplementation has been linked to both increased and decreased cardiovascular disease risk creating considerable uncertainty. Moreover, recent reports have shed uncertainty over the effectiveness of calcium supplements to reduce risk of fracture. The evidence for calcium supplementation effects to both reduce risk of fracture and increase coronary heart disease and mortality are reviewed. Although the importance of good calcium nutrition is well known, determining the advantage of calcium supplementation to either bone or heart health has been hampered by poor subject compliance and study design flaws. At present, the current Recommended Dietary Allowances for calcium still appear to be a good target with potential risks for chronic disease if intakes fall too short or greatly exceed these recommendations.