cssi/SciSciGPT-SciSciNet huggingface dataset:
Production of channel catfish with sperm cryopreserved by rapid non-equilibrium cooling☆

This report describes the feasibility of using vitrification for fish sperm. Vitrification can be used to preserve samples in the field and offers an alternative to conventional cryopreservation, although it has not been systematically studied for sperm of aquatic species. The overall goal of the project was to develop streamlined protocols that could be integrated into a standardized approach for vitrification of aquatic species germplasm. The objectives of the present study in channel catfish (Ictalurus punctatus) were to: (1) evaluate the acute toxicity of 5%, 10%, 20% and 30% methanol, N,N-dimethyl acetamide, dimethyl sulfoxide, 1,2-propanediol, and methyl glycol; (2) evaluate a range of devices commonly used for cryopreservation and vitrification of mammalian sperm; (3) compare vitrification with and without cryoprotectants; (4) evaluate the post-thaw membrane integrity of sperm vitrified in different cryoprotectant solutions, and (5) evaluate the ability of vitrified sperm to fertilize eggs. Cryoprotectant concentrations of higher than 20% were found to be toxic to sperm. Methanol and methyl glycol were the least toxic at a concentration of 20% with an exposure time of less than 5 min. We evaluated a method reported for human sperm, using small volumes in loops (15 μl) or cut standard straws (20 μl) with and without cryoprotectants plunged into liquid nitrogen. Cryoprotectant-free vitrification using loops did not yield fertilization (assessed by neurulation), and the fertilization rates observed in two trials using the cut standard straws were low (~2%). In general, fertilization values for vitrification experiments were low and the use of low concentrations of cryoprotectants yielded lower fertilization (<10%) than the use of vitrification solutions containing high cryoprotectant concentrations (as high as 25%). The highest neurulation obtained was from a mixture of three cryoprotectants (20% methanol+10% methyl glycol+10% propanediol) with a single-step addition. This was reflected in the flow cytometry data from which the highest membrane integrity using loops was for 20% methanol+10% methyl glycol+10% propanediol (~50%). We report the first successful sperm vitrification in fish and production of offspring from vitrified sperm in channel catfish. Although the fertilization values were low, at present this technique could nevertheless be used to reconstitute lines (especially in small aquarium fishes), but it would require improvement and scaling up before being useful as a production method for large-bodied fishes such as catfish.
Attentional demand requirements of an automobile moving-map navigation system

The objective of this research was to assess the driver visual attentional demand requirements of an operational in-car navigation system. Thirty-two driver subjects ranging in age from 18 to 73 drove a specially instrumented vehicle on various types of public roadways with varying traffic conditions. Drivers performed both specific navigation system tasks and conventional tasks using dashboard instrumentation. Comparisons were then made between the two types of tasks. Results show that the demand of most of the navigation tasks was comparable to that of one or more conventional tasks. Modifying the remaining navigation tasks to make information more readily available would reduce their demand.
A base composition analysis of natural patterns for the preprocessing of metagenome sequences.

Background On the pretext that sequence reads and contigs often exhibit the same kinds of base usage that is also observed in the sequences from which they are derived, we offer a base composition analysis tool. Our tool uses these natural patterns to determine relatedness across sequence data. We introduce spectrum sets (sets of motifs) which are permutations of bacterial restriction sites and the base composition analysis framework to measure their proportional content in sequence data. We suggest that this framework will increase the efficiency during the pre-processing stages of metagenome sequencing and assembly projects.
Cell disorganization and stimulation of mitosis in cultured leopard frog lens

Abstract Within 12 h of explantation of Rana pipiens lenses the epithelial cells undergo a striking disorganization. Cells originally in outlying areas accumulate at the anterior polar region. Approxim. 4 days after isolation mitotic figures become numerous in the accumulation zone (AZ). The increases in DNA, RNA and protein syntheses, without which mitotic activity fails to occur in these tissues, all occur in the AZ. The formation of an AZ does not occur at 4 °C and it becomes more accentuated as the temperature is elevated. Inhibition of glycolysis (but not of oxidative phosphorylation) also prevents cellular migration. Serum does not have to be present in the incubation medium in order for migration to occur in frog lenses but its presence favors mitotic activity. Tritiated actinomycin D is bound to a greater extent in the AZ than in other areas. The increase in binding occurs prior to the onset of DNA synthesis. It is considered that the AZ is the site of a series of activations of genes that control the mitotic process. It is tentatively held that in the lens the arousal of these genes may be due to destabilization of the outer membranes of the cells composing the accumulation zone.
Who owns America? : social conflict over property rights

Land ownership by individual citizens is a cornerstone of American heritage and a centerpiece of the American dream. Thomas Jefferson called it the key to our success as a democracy. Yet the question of who owns America not only remains unanswered but is central to a fundamental conflict that can pit private property rights advocates against government policymakers and environmentalists. Land use authority Harvey M. Jacobs has gathered a provocative collection of perspectives from eighteen contributors in the fields of law, history, anthropology, economics, sociology, forestry, and environmental studies. "Who Owns America?" begins with the popular view of land ownership as seen though the television show "Bonanza!" It examines public regulation of private land; public land management; the roles culture and ethnic values play in land use; and concludes with Jacobs title essay. "Who Owns America?" is a powerful and illuminating exploration of the very terrain that makes us Americans. Its broad set of theoretical and historical perspectives will fascinate historians, environmental activists, policy makers, and all who care deeply about the land we share."
The effect of various steroids on the hyperglycemic action of glucagon.

ABSTRACT One hundred and forty-four patients receiving various steroid hormones were studied by the glucagon tolerance test as standardized by the authors. Neither 400 mg. of cortisone ina 24-hour period nor prolonged prednisone therapy caused an appreciable alteration of thehyperglycemic response to glucagon. Three patients with either spontaneous or induced Cushing's syndrome did not respond excessively to glucagon. Ethinyl estradiol, diethylstilbestrol, progesterone and ethisterone failed to alter the hyperglycemic response to glucagon significantly. Normethandrone and norethandrolone completely and uniformly abolished the normal hyperglycemic response to glucagon, whereas 3 chemically or physiologicallysimilar compounds—norethynodrel, nondrolone, and 17-(1-methallyl)-19-nortestosterone—failed to have any effect. Methyltestosterone, testosterone propionate, testosterone and fluoxymesterone either depressed or abolished the glucagon hypergtycemia in some,but not all, patients tested while receiving thes...
Moderate prenatal carbon monoxide exposure produces persistent, and apparently permanent, memory deficits in rats

The effects of moderate (150 +/- 2 ppm) prenatal carbon monoxide (CO) exposure (maternal HbCO concentrations of 15.6 +/- 1.1%) on learning and memory were assessed in young and aged adult rats using a two-way active avoidance paradigm. In experiment 1, the prenatal CO-exposed rats at 120 days of age acquired a conditioned avoidance response equally well as control animals in a 100-trial session. However, following a 24-hr interval the CO-exposed rats failed to demonstrate significant retention of the task as indicated by the absence of significant improvement in performance over the indicated by the absence of significant improvement in performance over the previous day; control subjects did show significant retention. In experiment 2, in which 120-day-old animals received 50 training trials per day until a criterion of ten consecutive avoidance responses was met, the prenatal CO-exposed subjects again acquired the task as well as control animals. When tested for retention 28 days later, a significant memory impairment was again observed in terms of trials required to reattain the avoidance criterion as well as in total percent avoidance responding. In neither experiment did an analysis of initial or average latency to escape the footshock stimulus reveal any significant alterations. These latter results suggest that the observed performance impairment reflected a memory deficit and not a disruption of sensory, motor, or motivational factors. In experiment 3, prenatal CO-exposed rats approximately 1 year of age (300-360 days of age) showed impairment relative to air-exposed controls in both the original learning and retention of the two-way avoidance response. Again, however, there was no evidence for alterations in performance factors per se. Collectively these data indicate that while young adult rats prenatally exposed to 150 ppm CO demonstrate an associative deficit restricted to memory impairment, aged adults similarly exposed during the prenatal period display a more pronounced deficit similar to that recently reported for animals tested as juveniles. The importance of parametric manipulations in uncovering long-term toxicity is also discussed.
Asymmetric properties of ion current 1/f noise in conically shaped nanopores

We study ion currents in single rectifying conically shaped nanopores of various opening diameters and analyze the 1/f spectral behavior of the current fluctuations. The 1/f noise characteristics show an asymmetry with respect to the externally applied voltage. When in the high conductance state, the normalized 1/f noise associated with ion current signals increases with applied voltage, while in the low conductance state the 1/f noise shows equilibrium, voltage-independent fluctuations. The pore diameter and salt concentration play a direct role in defining these noise properties and influence the frequency range of the 1/f noise occurrence. We describe this behavior for a range of nanopore diameters and electrolyte concentrations.
Linear stability of natural symplectic maps

Abstract We calculate linear stability boundaries for natural symplectic maps, which are symplectic mappings derived from Lagrangian generating functions having positive definite kinetic energy. Simplified stability conditions are obtained in terms of the Hessian of the potential and applied to a four-dimensional pair of coupled standard maps.
A new time domain, multistage permutation algorithm (switching systems)

It is shown that a frame of N time slots can be arbitrarily permuted with 2log/sub 2/N-1 controlled exchange switches with associated delay elements. This is an improvement over previously known interconnection networks that require O(N) exchange elements. The proof utilizes the recursive algorithm of V.E. Benes (1965) and the time interchange properties of a particular configuration of a single exchange element. The architecture is especially applicable in optical systems, since optical exchange switches are among the simplest optical logic devices to build, are inherently very fast, and are the best developed, although expensive. >
Could Different Retirement Benefits Result in More Effective Teachers

We evaluate the chance that changing retirement benefits will lead to greater teacher effectiveness. Changing from defined benefit pensions to defined contribution or cash balance plans would raise initial compensation and effectiveness, while it would increase turnover and thus lower effectiveness. We simulate the effects of higher initial compensation and greater turnover on teacher effectiveness from changing retirement plans and calculate the potential transition costs. There is a 60–70 percent chance that effectiveness would fall if retirement benefits are changed. Transition costs could amount to 0.8 percent of payroll in the third decade after changing retirement benefits.
Addition of Soybean Trypsin Inhibitor to Bovine Colostrum: Effects on Serum Immunoglobulin Concentrations In Jersey Calves

Secretion of trypsin by the neonate may reduce absorption of Ig from colostrum and increase failure of transfer of passive immunity, particularly for calves fed after 12 h of age. Jersey calves (n = 48) were used in a 2 x 2 factorial arrangement of soybean trypsin inhibitor (0 or 1 g) added to 1 L of maternal colostrum at the first two feedings and time of initial feeding (.65 or 12 h of age). A second colostrum feeding was offered 12 h after the initial feeding. Maternal colostrum was analyzed for Ig by radial immunodiffusion and trypsin inhibitor by radial protease diffusion. Jugular blood was sampled at 0, 12, 24, and 48 h after initial feeding, and serum was analyzed for IgG and IgM. Addition of trypsin inhibitor increased serum Ig and total serum protein concentrations, regardless of age at first feeding. Concentrations of serum IgG and IgM were increased 16 and 30%, respectively, when trypsin inhibitor was fed. Age of first feeding did not affect concentrations of IgG or IgM in serum. Supplementation of colostrum with trypsin inhibitor improved transfer of passive immunity to neonatal Jersey calves.
Regeneration after nerve transection: Effect of inhibition of collagen synthesis

Abstract Dense collagen scar forms at the cut ends of transected nerves, and impedes nerve regeneration. To minimize scarring, we treated rats with the proline analog, cis -hydroxyproline, from day 4 to 21 after sciatic nerve transection and reanastomosis. Twenty-eight days after surgery, there was 47% less collagen in the distal nerve stump of treated rats than of controls. Seventy days after surgery, posterior tibial nerve content of the myelin lipids, sulfatide, and unesterified cholesterol, was 40% higher in treated rats than in controls.
A new paradox in viscous hydrodynamics

which have givcn rise to the wcll-known Stokes paradox [I-4], the Whitehead paradox [5], and the Filon paradox [6, 7]. Our purpose hcrc is to rcvcal a new paradox associated with the form of (I) suggcstcd by OSEEN [8] whcrc Wo is a non-zero constant vcctor. Within the framework of thc Oscen equations, we direct our attcntion to those solutions corresponding to flows which adhere to the exterior of an obstacle and tend to a uniform flow at infinity. For those flows wc will cstablish the rathcr uncxpcctcd property that, for any given obstacle shape, the magnitude of the force on the obstacle in the direction of the uniform flow (i.e., thc drag) is left unchangcd whcn the dircction of the uniform flow is rcvcrscd. We hasten to add that this holds for two and three dimensional flows independent of obstacle symmetry the paradox hcre is the lack of dcpcndcnce on obstacle symmetry. Surely for certain symmctricaIIy shapcd obstacles this condition would bc cxpcctcd to hold, but one has only to think of flow past a wedge or a conc to sense the lack of reality in this property. This indifference of the drag to flow reversal is somewhat suprising in view of thc unsymmctrical form of the operator in (I) whcn w 0 =~ 0. In constrast, one might anticipate this propcrty when wo = 0, since the Stokes cquations arc known not to exhibit a "wakc" bchavior. Moreover, we will show that thc form chosen for the lincarization constant w 0 is of primary importancc.
The origin of biotite in Archaean meta-sediments near Yellowknife, N.W.T., Canada. a discussion

The development of biotite in low-grade metamorphic rocks is an interesting problem, and the reactions proposed for it are almost as numerous as the persons who have written articles on the subject. Ideally, in approaching the problem of defining such a reaction one would study rocks representing both sides of the reaction equilibrium. If an equation can be discerned relating the higher and lower grade mineral asse~nblages it should meet the criteria that : 1) The changes in mineral assemblages or mineral composition proposed by the equation are observed in nature. 2) The equation can be balanced using the composition of naturally coexisting phases; and the proportions of reactants and products in the balanced equation are consistent with the observed mineralogy. 3) A V and AS calculated for the equation agree with the metamorphic gradient inferred from field relations. The biotite producing reaction proposed by Ramsay (1973a) in the paper under discussion is: Chlorite + Muscovite (1) AIlmenite --> Biotite AMuscovite (2) -~ H~O A( Qtz, Rutile, K-feldspar)
Rykūkyu's tribute-tax to Satsuma during the Tokugawa period

In 1609, Satsuma, at the southern tip of Kyūshū, conquered Okinawa (then called the Ryūkyū Kingdom). Throughout the subsequent Tokugawa period, Satsuma was said to have kept the Ryūkyūans in a state of virtual slavery by plundering the profits of the lucrative Sino-Ryūkyūan trade and imposing an excessively heavy tribute-tax on the native products. This exploitation of Ryūkyū's trade and native resources was reported to have been one of the important financial resources for Satsuma; and one that made possible Satsuma's vigorous political and military activities in the middle nineteenth century leading to the Meiji Restoration of 1868. In spite of such claims, no study of this topic has been made except those that have been strongly colored by the sympathies of the writer.
The temporal patterning of 40–60 kHz ultrasonic vocalizations and copulation in the rat (Rattus norvegicus)

Ultrasonic vocalizations are associated with copulatory behavior in the rat; however, the precise temporal relationship of these vocalizations to mating events is not known. In this study, 40–60 kHz ultrasonic vocalizations were recorded during sexual behavior and related to the periodicity of events that occur during mating. The occurrence of these ultrasounds was correlated with indices of sexual motivation. Ultrasonic vocalizations serve both to reflect and affect the arousal levels of the mating pair. The patterning of vocalizations suggests that these sounds play an important role in the coordination of male and female activity thereby facilitating the integration of mating behavior of the species.
The effects of partial and complete denervation on adult newt forelimb blastema cell-cycle parameters

Abstract The adult newt blastema cell-cycle time (cct) was measured by the percentage of labeled mitoses (PLM) method at the early-bud and mid-bud stages and was found to be 42.9 and 42.7 h, respectively. At both stages, the DNA synthetic phase (S) occupied the majority (75%) of the cct. However, the blastema labeling index (LI) after a 2-h pulse of 3 H-thymidine was less than 30% i.e., considerably less than predicted from the ratio of the duration of S over the cct. Compared to that of controls, the PLM plot for partially denervated blastemas exhibited a coincident and equal-sized first peak of labeled mitoses and a coincident but smaller second peak of labeled mitoses. After 24 h of continuous labeling, the LI of control blastemas reached 53%, whereas the LIs of partially denervated and completely denervated blastemas reached only 33% and 20%, respectively. These results are consistent with the view that many cells of adult newt blastemas are not actively progressing through the cell cycle and that the number of noncycling cells is increased by partial or complete denervation. The noncycling cells are probably in the G 1 phase of the cell cycle.
Utility of immunofluorescence testing for vascular IgA in adult patients with leukocytoclastic vasculitis.

Objectives: The purpose of this study was to examine the utility of immunofluorescence (IF) testing in patients with leukocytoclastic vasculitis (LCV), particularly with regard to usefulness in the diagnosis of Henoch-Schonlein purpura (HSP). Methods: We retrospectively analyzed the results of IF testing in 96 patients with LCV and compared results with clinical criteria and clinical impression at the time of biopsy by review of the medical record. Results: Sensitivity and specificity of vascular immunoglobulin A (IgA) for the diagnosis of HSP were 0.86 and 0.84, respectively. Positive predictive value was 0.48 and negative predictive value was 0.97. Of the 53 patients with LCV who did not meet clinical criteria for HSP and carried a low clinical suspicion for the disease at the time of biopsy, seven had moderate to strong staining for vascular IgA. Only one of these patients was determined to have HSP. Conclusions: Our data confirm that vascular IgA is nonspecific and also demonstrate that the utility of IF studies for vasculitis is influenced by the clinical presentation and the clinician’s level of suspicion for HSP. Our data show that the clinical features and the overall clinical impression are helpful in selecting which patients are most likely to benefit from IF testing.
Antimicrobial and antibiofilm activity of cathelicidins and short, synthetic peptides against Francisella

Abstract Francisella infects the lungs causing pneumonic tularemia. Focusing on the lung’s host defense, we have examined antimicrobial peptides as part of the innate immune response to Francisella infection. Interest in antimicrobial peptides, such as the cathelicidins, has grown due their potential therapeutic applications and the increasing problem of bacterial resistance to commonly used antibiotics. Only one human cathelicidin, LL-37, has been characterized. Helical cathelicidins have also been discovered in snakes including the Chinese King Cobra, Naja atra (NA-CATH). Four synthetic 11-residue peptides (ATRA-1, -2, -1A and -1P) containing variations of a repeated motif within NA-CATH were designed. We hypothesized that these smaller synthetic peptides could have excellent antimicrobial effectiveness with shorter length (and less cost), making them strong potential candidates for development into broad-spectrum antimicrobial compounds. We tested the susceptibility of F. novicida to four ATRA peptides, LL-37, and NA-CATH. Two of the ATRA peptides had high antimicrobial activity (μM), while the two proline-containing ATRA peptides had low activity. The ATRA peptides did not show significant hemolytic activity even at high peptide concentration, indicating low cytotoxicity against host cells. NA-CATH killed Francisella bacteria more quickly than LL-37. However, LL-37 was the most effective peptide against F. novicida (EC50 = 50 nM). LL-37 mRNA was induced in A549 cells by Francisella infection. We recently demonstrated that F. novicida forms in vitro biofilms. LL-37 inhibited F. novicida biofilm formation at sub-antimicrobial concentrations. Understanding the properties of these peptides, and their endogenous expression in the lung could lead to potential future therapeutic interventions for this lung infection.
New nonsymmetric P(OH)3 species. Comparison with the C3 isomer and themochemistry at the DFT, MP2, and CCSD(T) levels of theory.

Two new less-symmetric P(OH) 3 isomers that are more stable than the C 3 structure are found at the density functional theory (B3PW91, B3LYP), MP2, and CCSD(T) levels with the large aug-cc-pvdz/pvtz basis sets. The C 1 and C 3 structures are qualitatively different from those found for the As(OH) 3 molecule. An additional lower lying P(OH) 3 structure with C s symmetry has been obtained. With the largest basis set the C s isomer is predicted to be the most stable. However, the inclusion of zero-point-energy corrections induces an inversion between the C s and C 1 isomers, with the latter becoming the lowest energy structure at the highest correlated level. Increasing inclusion of electronic correlation effects reduces the energy difference between the C 1 and C s structures while the C 1 -C 3 energy difference and C 1 -C s interconversion barrier become larger. In all cases, energy differences and barrier heights are around 1 kcal/mol.
Aging Differentially Affects the Re-entrainment Response of Central and Peripheral Circadian Oscillators

Aging produces a decline in the amplitude and precision of 24 h behavioral, endocrine, and metabolic rhythms, which are regulated in mammals by a central circadian pacemaker within the suprachiasmatic nucleus (SCN) and local oscillators in peripheral tissues. Disruption of the circadian system, as experienced during transmeridian travel, can lead to adverse health consequences, particularly in the elderly. To test the hypothesis that age-related changes in the response to simulated jet lag will reflect altered circadian function, we examined re-entrainment of central and peripheral oscillators from young and old PER2::luciferase mice. As in previous studies, locomotor activity rhythms in older mice required more days to re-entrain following a shift than younger mice. At the tissue level, effects of age on baseline entrainment were evident, with older mice displaying earlier phases for the majority of peripheral oscillators studied and later phases for cells within most SCN subregions. Following a 6 h advance of the light:dark cycle, old mice displayed slower rates of re-entrainment for peripheral tissues but a larger, more rapid SCN response compared to younger mice. Thus, aging alters the circadian timing system in a manner that differentially affects the re-entrainment responses of central and peripheral circadian clocks. This pattern of results suggests that a major consequence of aging is a decrease in pacemaker amplitude, which would slow re-entrainment of peripheral oscillators and reduce SCN resistance to external perturbation.
Interest rate equalization and nonequalization by trade in Leontief-Sraffa models

Abstract A half-dozen theorems and some corollaries concerning equalization of factor prices in a time-phased Leontief-Sraffa system with steady-state profit rates are carefully stated and discussed. An example is the new Mainwaring theorem, that a 1-technique world will either have the normalized price ratio vector independent of the profit rate or uniquely determined by it. Another example is that, when intermediate goods can be imported, unchanged profit rates and changed tastes can negate the nonsubstitution theorem and alter price ratios, since now the world has more than one primary (i.e. geographical) labor.
The Safety Factor for Electroventilation Measured by Production of Cardiac Ectopy in the Anesthetized Dog

The safety factor of electroventilation ( ie, the ratio of the current required to produce an ectopic beat to the current required to produce an inspired volume of 225 ml, which is approximately twice tidal volume) was determined in 12 pentobarbital-anesthetized dogs using transthoracic electrodes positioned at the optimal electroventilation site. The optimal stimulation site for electroventilation was first determined using hand-held, stimulating electrodes. Then electrodes, 4.1 cm in diameter, were sutured bilaterally to the optimal stimulation site. The relationship between inspired volume and stimulus intensity was determined using a 0.8-s burst of stimuli (60/s) with a pulse duration of 0.1 ms. Using the same electrodes, the threshold current for producing ectopic beats was determined for single pulses ranging from 0.1 to 10 ms duration. In all dogs, the current required to produce an ectopic beat increased greatly as the pulse duration decreased. At 0.1 ms, the safety factor for electroventilation was calculated to be 25.8. (Chest 1989; 95:214-17)
Characteristics of Nonopinion and No Opinion Response Groups

T HE assessment of attitudes and opinions on issues or conditions not well defined or understood by the public is likely to lead to large frequencies of equivocal ("don't know" or "no opinion") responses in sample surveys. At this early stage of research, the social scientist may find the accurate classification of equivocal attitudinal responses particularly difficult, but the distinction between "don't know," a nonopinion state, and "no opinion," an ambivalent or undecided attitudinal position, is just as crucial at this stage as it is after attitudes are more firmly established and more widespread. For example, in monitoring, over time, the public acceptance or rejection of technical solutions to social problems, it is important in the initial data set to separate the informed but undecided no opinion from the uninformed
Electron-capture GLC determination of clobazam and desmethylclobazam in plasma

Electron-capture GLC was utilized for simultaneous quantitation of clobazam, a 1,5-benzodiazepine derivative, and its active metabolite, desmethylclobazam, in human plasma and serum. After addition of diazepam as the internal standard, samples were extracted into benzene–isopentanol. The organic extracts were evaporated to dryness, reconstituted, and subjected to chromatographic analysis without derivatization or cleanup. All three compounds were resolved completely and had favorable chromatographic properties using an OV-101 liquid phase. The limits of detection are 3–5 ng/ml for clobazam and 5–10 ng/ml for desmethylclobazam. Relative standard deviations for identical samples do not exceed 6%. The application of the method to a clinical pharmacokinetic study is demonstrated.
Near-infrared studies of the satellites of Saturn and Uranus

New JHK photometry and spectrometry (1.4–2.6 μm) are presented for Enceladus, Hyperion, Phoebe, Umbriel, Titania, and Oberon. From spectral signatures, mainly in the 2-μm region, water ice is verified on Enceladus and identified on Hyperion and the three Uranian satellites. The JHK photometry shows that Phoebe is different from all other satellites and asteroids observed thus far. The new photometry corroborates the earlier conclusion by Cruikshank et al. (1977) Astrophys. J 217, 1006–1010] that the Uranian satellites, as a class, have overall surface reflectances different from other water-ice-covered satellites, and the reason for the difference remains unclear. The diameters and the masses of the Uranian satellites are reviewed in light of the probable high albedo representative of ice-covered surfaces and the new dynamical studies by Greenberg [(1975) Icarus 24, 325–332; (1976) Icarus 29, 427–433; (1978) Bull. Amer. Astron. Soc. 10, 585].
On-line near infrared bioreactor monitoring of cell density and concentrations of glucose and lactate during insect cell cultivation.

Abstract Near infrared spectroscopy is demonstrated as a suitable method for monitoring real time cell density and concentrations of glucose and lactate during insect cell cultivation. The utility of this approach is illustrated during the cultivation of Trichoplusia ni BTI-Tn-5B1-4 insect cells in a stirred-tank bioreactor. On-line near infrared measurements are made by passing unaltered culture medium through an autoclavable near infrared flow-through sample cell during the cultivation process. Single-beam near infrared spectra were collected over the combination spectral range (5000–4000 cm−1) through a 1.5 mm path length sample. Cell density calibration model was established by uni-variable linear regressions with measured mean absorbance values of on-line spectra collected during a cultivation run. Calibration models are generated for glucose and lactate by regression analysis of both off line and on line spectra collected during a series of pre-measurement cultivation runs. Analyte-specific calibration models are generated by using a combination of spectra from both natural, unaltered samples and samples spiked with known levels of glucose and lactate. Spiked samples are used to destroy concentration correlations between solutes, thereby enhancing the selectivity of the calibration models. Absorbance spectra are used to build partial least squares calibration models for glucose and lactate. The calibration model for cell density corresponds to a univariate linear regression calibration model based on the mean absorbance between 4750 and 4250 cm−1. The standard errors of prediction are 1.54 mM, 0.83 mM, and 0.38 × 106 cells/mL for the glucose, lactate, and cell density models, respectively.
UKF based estimation of synchronous generator electromechanical parameters from phasor measurements

The paper proposes an Unscented Kalman Filter (UKF)-based algorithm to estimate the electromechanical parameters and states of synchronous machines (rotor angle, q-axis reactance, inertia, damping and mechanical power). The algorithm uses observations or measurements available at the output terminal of the machine polluted by colored noise. Testing of the algorithm was conducted against a model of the same complexity and a model of a higher complexity. The contribution of this paper is twofold: 1) the algorithm is able to estimate electromechanical parameters such as inertia H and damping D which have not been investigated in other machine estimation papers. Modeling error is modeled as colored noise to enhance the estimation capability; and 2) a dual UKF filter is set up to carry out the estimation where the estimator of q-axis reactance is separated from the other states and parameters. Such set up solves the difficulty of UKF based estimation. Two case studies demonstrate the feasibility of the estimation.
Microbial leaching of arsenic from low‐sulfide gold mine material

Abstract Drainages from high‐sulfide tailings near abandoned lode deposits in Alaska, U.S.A., and Yukon, Canada, were found to be acidic, to contain large numbers of Thiobacillus ferrooxidans, and to have high concentrations of dissolved arsenic. Drainages from active placer gold mines are not acidic, but T. ferrooxidans and concentrations of dissolved arsenic exceeding 10 μg/L are found in some streams affected by placer mine drainage. Placer mine material containing low amounts of sulfides (326 (μg/g) and moderately high amounts of arsenic (700 μg/g) was leached with growing cultures of T. ferrooxidans, T. ferrooxidans‐spent filtrate, and acid ferric sulfate. The results showed that while more arsenic was released from this material by growing cultures of T. ferrooxidans than by abiotic controls, acid ferric sulfate released much more arsenic than did either growing cultures of T. ferrooxidans or spent culture filtrate containing oxidized iron. Cation exchange chromatography showed that oxidized iron fr...
O.P.: collection as celebration of children's self-organized play

‘Organized play’ is a term now used as a comparison to ‘free play’, a false dichotomy if one examines the collected works of Iona and Peter Opie. As documented by the Opies, children have tradition...
Preliminary study of matching pursuit for extracting GPR rebar reflections

Ground penetrating radar (GPR) has developed into a primary investigation tool for the non-destructive evaluation of reinforced concrete bridge deck. The collected GPR signals are generally composed of direct wave, rebar reflections, bottom reflection and noise. Before making GPR-based predictions, rebar reflections need to be extracted first. One obstacle is that the first rebar layer is in the shallow subsurface in some cases and the target signals may be overlapped with the direct waves. Another problem associated is that the testing surfaces may be rough in real field testing environments, which lead to strong uneven direct waves in the collected signals. This kind of direct wave cannot be removed by the commonly adopted average removing method. In this paper, Matching pursuits equipped with a customized dictionary are applied to deal with the above mentioned two problems. The dictionary is built based on the excitation function and the electromagnetic scattering mechanisms. Compared to the commonly used Gabor dictionary, the proposed dictionary is more adapted to the GPR wavefronts and each target signal can be reconstructed by just one atom. In addition, there is no need for a reference signal that is not always available. The performance of the proposed method is evaluated by simulation data in this paper.
Hoffa Fracture of the Femoral Condyle

In this report, we present a case of an uncommon coronal fracture of the femoral condyle, known as a Hoffa fracture. Classification of these injuries and commonly associated injuries are discussed. We describe previously proposed mechanisms of injury and review the current literature. The difficulty in establishing radiologic diagnosis on the basis of radiography exclusively is emphasized. Finally, current approaches to operative fixation are outlined.
Dislocation fiber interactions in short fiber reinforced metal matrix composites during creep and during thermal cycling

Short fiber reinforced metal matrix composites (SFR MMCs) are attractive engineering materials because they exhibit increased strength and wear resistance as compared to the fiber free matrix materials. For example, an aluminum alloy containing 15 volume percent of Al{sub 2}O{sub 3} fibers with average dimensions of 200 {micro}m length and 3 {micro}m diameter exhibits an improved creep strength with respect to the fiber free matrix. In addition to extended periods of isothermal and static creep loading high temperature components are subjected to temperature changes which are associated with thermal stresses. Thermal cycles can be due to start up and shut down events and can also be a consequence of anisothermal operating conditions. In short fiber reinforced aluminum alloys, in the stress and temperature range of interest, dislocation creep governs the deformation behavior of the MMC`s metallic matrix. It is therefore interesting to discuss the role of dislocations during creep and during thermal cycling of SFR MMCs. In the present paper the authors describe some basic dislocation mechanisms near the fiber/matrix-interface (FMI) of SFR MMCs. They first consider dislocation structures which are associated with the processing of SFR MMCs. Then dislocation processes which are associated with (1) static isothermal creep andmore » (2) thermal cycling are discussed. Common and distinct features of the associated dislocation structures in the matrix zone near the FMI are highlighted. The authors then use the insight they have gained to qualitatively understand the role of dislocations in the macroscopic response of a SFR MMC under more complex load profiles.« less
A comparison of cognitive strategies in modifying the cognitive style of impulsive third-grade children

The present study was designed to test the relative effectiveness of two cognitive strategies in the modification of an impulsive cognitive tempo among school-age children. Twenty-four third-grade children were assigned through a three-step randomized block procedure to one of the four following experimental conditions: (1)Scanning Strategy Instructions, (2)Verbal Self-Instructions, (3)Scanning Strategy Instructions plus Verbal Self-Instructions, and (4)Attention Control. The results of the current investigation suggest that a streamlined cognitive training procedure, involving either scanning strategy instructions or verbal self-instructions, is sufficient when the goal is the modification of an impulsive cognitive tempo exhibited by normal elementary school children. The effects of the cognitive training procedures generalized to the children's academic work, but not to their nonacademic behavior in the classroom.
Determining the Phagocytic Activity of Clinical Antibody Samples

Antibody-driven phagocytosis is induced via the engagement of Fc receptors on professional phagocytes, and can contribute to both clearance as well as pathology of disease. While the properties of the variable domains of antibodies have long been considered critical to in vivo function, the ability of antibodies to recruit innate immune cells via their Fc domains has become increasingly appreciated as a major factor in their efficacy, both in the setting of recombinant monoclonal antibody therapy, as well as in the course of natural infection or vaccination1-3. Importantly, despite its nomenclature as a constant domain, the antibody Fc domain does not have constant function, and is strongly modulated by IgG subclass (IgG1-4) and glycosylation at Asparagine 2974-6. Thus, this method to study functional differences of antigen-specific antibodies in clinical samples will facilitate correlation of the phagocytic potential of antibodies to disease state, susceptibility to infection, progression, or clinical outcome. Furthermore, this effector function is particularly important in light of the documented ability of antibodies to enhance infection by providing pathogens access into host cells via Fc receptor-driven phagocytosis7. Additionally, there is some evidence that phagocytic uptake of immune complexes can impact the Th1/Th2 polarization of the immune response8. Here, we describe an assay designed to detect differences in antibody-induced phagocytosis, which may be caused by differential IgG subclass, glycan structure at Asn297, as well as the ability to form immune complexes of antigen-specific antibodies in a high-throughput fashion. To this end, 1 μm fluorescent beads are coated with antigen, then incubated with clinical antibody samples, generating fluorescent antigen specific immune complexes. These antibody-opsonized beads are then incubated with a monocytic cell line expressing multiple FcγRs, including both inhibitory and activating. Assay output can include phagocytic activity, cytokine secretion, and patterns of FcγRs usage, and are determined in a standardized manner, making this a highly useful system for parsing differences in this antibody-dependent effector function in both infection and vaccine-mediated protection9.
Role of gonadal hormones in development of the sexual phenotypes.

Male and female embryos develop in an identical fashion during the initial portion of gestation. If the indifferent gonad differentiates into an ovary (or if no gonad is present), a female phenotype is formed. Male phenotypic differentiation, however, requires the presence of an endocrinologically active testis. Two secretion of the fetal testis, Mullerian inhibiting substance and testosterone, are responsible for male development. Studies of single gene mutations that interfere with androgen action indicate that testosterone itself is responsible for virilization of the Wolffian duct system into the epididymis, vas deferens, and seminal vesicle, whereas the testosterone metabolite dihydrotestosterone induces development of the prostate and male external genitalia. Thus, impairment of dihydrotestosterone formation results in a characteristic phenotype consisting of predominantly female external genitalia but normally virilized Wolffian ducts. The molecular mechanisms by which testosterone and dihydrotestosterone act during fetal development appear to involve the same high affinity receptor, a protein that transports both testosterone and dihydrotestosterone to the nucleus of target cells. When this receptor is either absent, deficient, or structurally abnormal, the actions of both testosterone and dihydrotestosterone are impaired, and the resulting developmental anomalies involve both internal and external genital structures.
Reactivity of Cl-P(+)-Cl toward cyclic organic ethers.

The dichlorophosphenium ion (Cl–P+–Cl) undergoes a variety of reactions with cyclic organic ethers in the gas phase in a Fourier-transform ion cyclotron resonance mass spectrometer. Most of the reactions are initiated by Cl–P+–Cl-induced heterolytic C–O bond cleavage. However, the observed final products depend on the exact structure of the ether. For saturated ethers, e. g., tetrahydropyran, tetrahydrofuran, and 2-methyltetrahydrofuran, the most abundant ionic product corresponds to hydroxide abstraction by Cl–P+–Cl. This unexpected reaction is rationalized by a multistep mechanism that involves an initial heterolytic C–O bond cleavage accompanied by a 1,2-hydride shift, and that ultimately yields a resonance-stabilized allyl cation and HOPCl2. The process is estimated to be highly exothermic (AM1 calculations yield ΔH = −(33–38) kcal mol−1 for the ethers mentioned above). However, the adducts formed from most of the unsaturated ethers are unable to undergo hydride shifts and hence cannot react via this pathway. In some of these cases, e. g., for 2,5-dihydrofuran and 2,5-dihydro-3,4-benzofuran, the C–O bond heterolysis is followed by oxygen/chlorine exchange to yield the O=PCl radical and a resonance-stabilized carbocation (AM1 calculations yield ΔH = −14 kcal mol−1 for the reaction of 2,5-dihydro-3,4-benzofuran). Hydride abstraction by Cl–P+–Cl also yields an abundant product for these two ethers. On the other hand, the ethers with low ionization energies, such as 2,3-dihydrofuran and 2,3-dihydrobenzofuran, react with Cl–P+–Cl by electron transfer. Finally, a unique pathway, addition followed by elimination of HCl, dominates the reaction with furan. The observed reactions are rationalized by thermochemical data obtained from semiempirical molecular orbital calculations.
Computer assisted testing: An alternative assessment option for students

Abstract Evidence indicates that students will voluntarily avail themselves of the retest option when it is offered in a course and will earn significantly higher grades with a more positive attitude toward their learning experience. The computer can be a valuable tool for teachers in generating multiple tests. Multiple tests can be easily constructed by placing a pool of test items in the computer and having the computer randomly select and print the number of test items wanted in each test or subtest. The computer printout of selected items can be reproduced for as many copies of the test as wanted.
Qualitative overview of randomized trials of aminoglycosides.

Abstract A qualitative overview was conducted of randomized clinical trials comparing two or more of the following aminoglycoside antibiotics—amikacin, gentamicin, netilmicin, sisomicin, and tobramycin—with respect to efficacy, nephrotoxicity, or auditory toxicity. Design features considered included number of participants in each treatment arm, proportion of randomized participants available for analysis, blinding of evaluators, and report of statistically significant results. The proportion of participants eligible for analysis was less than or equal to 75 percent for 66 percent of the comparisons regarding nephrotoxicity, 43 percent regarding efficacy, and 19 percent regarding auditory toxicity. Twenty-nine percent of the trials reported that evaluators were blinded to treatment group assignments. The results of most trials showed no significant differences, although sample sizes were, in general, smaller than necessary to detect moderate differences. Quantitative overviews may be a useful means of detecting real differences in risk that are not apparent from the results of several individual small trials.