cssi/SciSciGPT-SciSciNet huggingface dataset:
Hemoglobin transition in erythrocytes of developing chick. Studies with cell-free protein-synthesizing systems.

Abstract Cell-free hemoglobin-synthesizing systems from erythrocytes of 4- and 17-day chick embryos have been developed. These systems have been used to investigate possible structural and functional differences in factors involved in protein synthesis obtained from these different developmental stages. Each cell-free system consists of three major cellular fractions i.e., the S-100 supernatant, the salt-washed ribosomes, and the 0.5 m KCl ribosomal wash. When the ribosomal wash fraction from one developmental stage is included in a cell-free system containing ribosomes and S-100 supernatant from the other developmental stage, a drastic reduction in the kinetics of [ 3 H]leucine incorporation into globin products is observed, when compared to the homologous control cell-free systems. A similar depression of the kinetics of incorporation is observed when the mixed component is either the S-100 supernatant or the ribosomes. Control rates of incorporation can be reestablished when the corresponding homologous component is added back to the incubation mixture. The predominant types of hemoglobins produced in the salt-wash heterologous systems are those hemoglobins characteristic of the developmental stage of the salt wash. This seems to imply that the ribosomal salt-wash fraction may possess developmental stage specificity for the globins.
Comparative 100 Mc measurements at distances far beyond the radio horizon

Results of 100 Mc measurements are evaluated in terms of distributions of hourly medians of transmission loss. Transmitters were located at elevations of approximately 6200, 8800, and 14100 feet above mean sea level on the eastern slope of the Rocky Mountains. Receiving sites were located at distances of 230 and 400 miles from the transmitters. Various types of antennas were employed for transmitting and receiving. The results of studies of fading rate and fading range are reported for the 400 mile site by comparing signals received simultaneously on two different antennas. These results are compared to those expected from the application of the tropospheric scattering theory.
Coplanar Stripline Transitions

RF and microwave circuit components can be realized with input/output ports using either balanced or unbalanced planar transmission lines. Interconnections between these components will require a balun or a transition to transform an unbalanced port to a balanced port. This article presents several baluns or transitions, that are of either the Marchand or double-Y type. Keywords: transitions; Marchand balun; double-Y balun; coplanar stripline; microcoplanar stripline; coplanar waveguide
Subacute streptococcus viridans endarteritis superimposed on patent ductus arteriosus

Abstract A 51-year-old female with patent ductus arteriosus, suffered an episode of subacute Streptococcus viridans endarteritis twelve and one-half years previously. At the time, the diagnosis of a congenital cardiac lesion was based upon the absence of a history of rheumatic fever and the presence of a characteristic murmur, known to be of long duration. The diagnosis of superimposed infection rested upon the presence of irregular fever, chills, malaise, splenic enlargement, petechiae, and several episodes of pulmonary infarction, and was confirmed by blood cultures which repeatedly were positive for Streptococcus viridans . The treatment consisted of repeated blood transfusions, supportive therapy, and injections of an autogenous vaccine. After an illness of approximately fifteen months, she apparently recovered completely. The patient first came under the observation of one of the authors, with symptoms of mild circulatory failure, approximately eight years prior to the present admission. During the ensuing years the circulatory symptoms increased slowly but progressively. Approximately four and one-half weeks before admission to the hospital, clinical manifestations of superimposed infection, similar to those present twelve and one-half years previously, reappeared. During a twenty-three-day period of hospital observation, the clinical course was progressively downhill. The administration of both sulfapyridine and sulfathiazole was without sgnificant effect; and blood cultures revealed as many as fifty-two colonies of Streptococcus viridans per cubic centimeter. Operation was performed primarily for the purpose of eliminating the infection. The procedure consisted of double ligation of the ductus, by a modification of technique devised by one of the authors. A blood culture taken forty minutes after operation was sterile throughout fourteen days of incubation. Four blood cultures were taken subsequently, and these likewise were negative. Chemotherapy was not administered during the postoperative course. Approximately nine months have elapsed since operation. All manifestations of infection and of circulatory failure remain absent, and the patient is in better health than in many years. This is the first case of spontaneous recovery from subacute Streptococcus viridans infection superimposed upon a proved patent ductus arteriosus. It also is the first case of infected patent ductus in which, after recovery from an initial episode, the infection recurred. Finally, it is our third, in which operation upon a patent ductus arteriosus has been followed by recovery from infection.
The M51 system - Review of the interstellar medium

We review observations of the radio continuum, the atomic and molecular gas, the optical emission lines, X-ray and infrared emission in the disk, spiral arms, and nucleus of NGC 5194 and in the companion, NGC 5195. The composition, distribution and kinematics of the Interstellar Medium (ISM) are discussed.
The induced current in parallel wires over an imperfect ground from an incident EMP

The current that is induced in infinitely long, finitely conducting parallel wires over a finitely conducting plane earth from an incident electromagnetic pulse (EMP) is investigated. Frequency-domain expressions for this current are derived. Time domain results are obtained for the case of two wires at the same height above the earth for several wire spacings and ground parameters. It is shown that the coupling between the wires reduces the induced current compared to the current in a single wire. The low-angle case ( theta =6 degrees ) gives much larger currents than the broadside case ( theta =90 degrees ), but the induced current becomes zero when theta =0 degrees (where theta is the grazing angle). The maximum current was >
The heavens of the sky and the heavens of the heart: the Ottoman cultural context for the introduction of post-Copernican astronomy

In 1637 a Frenchman named Noel Duret (Durret) published a book in Paris that referred to the heliocentric Copernican system. In 1660 an Ottoman scholar named Ibrāhīm Efendi al-Zigetvari Tezkireci translated the book into Arabic. For more than three centuries this manuscript was buried in an Ottoman archive in Istanbul until it resurfaced at the beginning of the 1990s. The discovery of the Arabic text has necessitated a re-evaluation of the history of early modern Arabic natural philosophy, one that takes into account the intellectual context of Ibrāhīm Efendi and the overarching trends in the world of Sufi mysticism. These trends were reflected in art, literature, philosophy and natural philosophy. Using philological and cultural clues, as well as Ibrāhīm Efendi's own words, we can attempt deductions about why, how and for what purposes Ibrāhīm Efendi chose Duret's book for his project.
Irbesartan promotes erection recovery after nerve-sparing radical retropubic prostatectomy: a retrospective long-term analysis.

Study Type – Therapy (retrospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Erectile dysfunction following radical prostatectomy (RP) is among the most common and dreaded adverse effects of the surgery. Multiple studies confirm the potential benefit of various drug classes to accelerate the return of erectile function (EF) after RP. There is pre-clinical evidence supporting the use of angiotensin-receptor blockers (ARBs) for this purpose, although this has not been studied in humans. The present study shows that there may be a benefit in the recovery of EF post-RRP in patients taking a daily dose of irbesartan, an ARB, following RRP. In addition, the use of irbesartan may curb the loss of stretched penile length which occurs postoperatively. Further study in the form of prospective, randomized, placebo-controlled clinical trials are necessary to confirm these findings. OBJECTIVE • To evaluate retrospectively the potential benefit of administering irbesartan, an angiotensin-receptor blocker, to improve erectile function (EF) recovery after nerve-sparing radical retropubic prostatectomy (RRP). PATIENTS AND METHODS • Before surgery potent patients who underwent nerve-sparing RRP between April and December 2009 elected to start daily oral irbesartan 300 mg on postoperative day 1 (n= 17). A contemporaneously clinically matched cohort consisting of patients who declined irbesartan use served as the control group (n= 12). • Postoperative ‘on demand’ use of erectile aids (phosphodiesterase type 5 [PDE5] inhibitors and intracavernous injections) was adopted. • Potency was monitored by the administration of International Index of Erectile Function-5 (IIEF-5) questionnaires before surgery and at early (3 months) and long-term (12 and 24 months) postoperative intervals. • Stretched penile length (SPL) was measured both immediately and 3 months after surgery. RESULTS • EF status was no different between groups at baseline (P > 0.05). • While the IIEF-5 scores at 24 months after surgery were statistically similar between the two groups (control = 15.2 ± 2.0, irbesartan = 14.1 ± 3.1, P= 0.77), at 12 months the IIEF-5 scores of the irbesartan group were significantly higher than those of the control group (14 ± 2.6 vs. 7.2 ± 1.6, P < 0.05). • The proportional loss of SPL after RRP was less in the irbesartan than in the control group at 3 months (–0.9 ± 1.5% vs –5.6 ± 1.5, P < 0.05). CONCLUSION • Regular irbesartan use after nerve-sparing RRP in patients with normal preoperative erectile function could improve EF recovery after surgery and mitigate early loss of SPL.
The solubility of 40Ar and 84Kr in liquid hydrocarbons: Implications for Titan's geological evolution

[1] The solubility of argon and krypton in methane and ethane has been experimentally determined at Titan-relevant temperatures. At typical Titan surface temperature (94 K), argon and krypton solubilities are very large (47% in methane and 15% in ethane for Ar, 29% in methane and 43% in ethane for Kr), making liquid alkanes on Titan an important potential reservoir of 40Ar and other noble gases. Large subsurface reservoirs of liquid ethane and methane could be sufficient to trap much of the argon outgassing from Titan's interior, which can help explain the discrepancy between the potential amount of 40Ar produced inside Titan's interior and the amount observed in the atmosphere by Cassini-Huygens. Consequently, on Titan, liquid hydrocarbons may function as a buffer in the outgassing of volatiles from the interior, and they may strongly influence the evolution of the atmosphere's composition through the release of soluble gases upon evaporation and/or intake upon condensation.
Long-term changes in an oak forest's woody understory and herb layer with repeated burning1

Abstract Although fire exclusion is thought to be linked with declining plant diversity in oak forests, few studies have examined long-term changes in their shrub and ground layers resulting from repeated burning. In this study, we compare the composition and structure of woody understory and ground layer vegetation in burned and unburned oak forest after 17 years of annual dormant season low-intensity burns. Over time, burned forest had 97% reduction of shrubs and small saplings, but only 38% loss of stems in the > 5–10 cm size class. Canopy openness was similar in burned and unburned forest plots prior to the onset of burning, but it was significantly greater in burned forest after 17 years of fire. Ground layer vegetation structure also changed significantly, with responses differing by guilds. Spring herbs were the dominant guild before burning and did not change over time. However, cover and abundance of summer herbs increased over time in burned forest, probably in response to greater light assimila...
Noninterferometric tomographic reconstruction of 3D static and dynamic phase and amplitude objects

Non-interferometric intensity based methods of phase retrieval such as the transport of intensity (TI) employs a simple experimental technique for amplitude and phase reconstruction of a static object by capturing several diffraction patterns at different observation planes. The purpose of this work is to numerically and experimentally extend this technique to moving phase and amplitude objects. The simulation part is done based on solving the TI equation (TIE) using the Fast Fourier Transform (FFT) method, and the amplitude and the calculated phase in the detection plane is numerically back-propagated to the object plane using the paraxial transfer function. Furthermore, we illustrate how a static 3D phase and/or amplitude object can also be reconstructed tomographically by illuminating it at multiple angles. For illustration purposes, the object is mounted on a rotating stage and multiple diffraction patterns are captured for different angles and at different observation planes. The reconstructed optical fields are tomographically recomposed to yield the final 3D shape using a simple multiplicative technique. The tomographic technique can be generalized for the case of 3D moving objects. Finally, we have used TIE to determine the phase induced in a liquid due to heating by a focused laser beam, which causes self-phase modulation of the beam.
Roadmaps through Free Energy Landscapes Calculated Using the Multidimensional vFEP Approach

The variational free energy profile (vFEP) method is extended to two dimensions and tested with molecular simulation applications. The proposed 2D-vFEP approach effectively addresses the two major obstacles to constructing free energy profiles from simulation data using traditional methods: the need for overlap in the reweighting procedure and the problem of data representation. This is especially evident as these problems are shown to be more severe in two dimensions. The vFEP method is demonstrated to be highly robust and able to provide stable analytic free energy profiles with only a paucity of sampled data. The analytic profiles can be analyzed with conventional search methods to easily identify stationary points (e.g., minima and first-order saddle points) as well as the pathways that connect these points. These “roadmaps” through the free energy surface are useful not only as a post-processing tool to characterize mechanisms but can also serve as a basis from which to direct more focused “on-the-fl...
Separation and characterization of the lens proteins of the amphibian, Rana pipiens

The soluble lens proteins (α, β, and γ crystallins) of the adult American grass frog, R. pipiens, were investigated, using DEAE-cellulose ion-exchange chromatography and disc electrophoresis on polyacrylamide gels. Column chromatography of whole adult lens proteins, with a NaH2PO4-Na2HPO4-NaCl buffer elution program, revealed six fractions. The first to be eluted was identified as γ crystallin, the predominant lens protein of this organism; the second and third as β crystallins; and the fourth, fifth, and sixth as a crystallins. Disc electrophoresis of these fractions on polyacrylamide gels of appropriate porosity confirmed the identity of these proteins as separated by ion-exchange chromatography. Rechromatography of the isolated γ crystallin fraction of whole lens protein, employing a tris-HCl buffer elution system, resolved the γ crystallin into four distinct components. These individual γ crystallins exhibited different electrophoretic mobilities, as judged by their behavior in disc electrophoresis. This precludes the possibility that the fractions obtained are artifacts of the elution process, and confirms the existence of four γ crystallins in the lens of adult R. pipiens, as has been reported for mammalian (bovine) embryonic and adult γ crystallins. The phylogenetic and development implications of these findings are discussed.
How hydrophobic drying forces impact the kinetics of molecular recognition

A model of protein–ligand binding kinetics, in which slow solvent dynamics results from hydrophobic drying transitions, is investigated. Molecular dynamics simulations show that solvent in the receptor pocket can fluctuate between wet and dry states with lifetimes in each state that are long enough for the extraction of a separable potential of mean force and wet-to-dry transitions. We present a diffusive surface hopping model that is represented by a 2D Markovian master equation. One dimension is the standard reaction coordinate, the ligand–pocket separation, and the other is the solvent state in the region between ligand and binding pocket which specifies whether it is wet or dry. In our model, the ligand diffuses on a dynamic free-energy surface which undergoes kinetic transitions between the wet and dry states. The model yields good agreement with results from explicit solvent molecular dynamics simulation and an improved description of the kinetics of hydrophobic assembly. Furthermore, it is consistent with a “non-Markovian Brownian theory” for the ligand–pocket separation coordinate alone.
Effects of Explicitness in Conveying Severity Information in Product Warnings

Manufacturers typically provide consumers with a warning message on the label of potentially hazardous products in order to encourage their safe use. Warnings often vary in explicitness and severity, where explicitness refers to the specificity of the stated injury consequences and severity refers to the harshness of the consequences. This study examined the nature of the relationship between explicitness and severity and explored changes in people's perceptions of four common consumer products as a result of exposure to warnings that varied on these two dimensions. The results show that explicitness and severity are related. The results also demonstrated that exposure to explicit warnings produced an increase in rated severity of injury and intent to act cautiously with a product. Overall this study suggests that, unless they are explicit, warnings on common consumer products may not change perceptions and subsequent intentions to act cautiously.
Intelligent Damage Detection in Bridge Girders: Hybrid Approach

AbstractThis study is intended to facilitate damage detection in concrete bridge girders without the need for visual inspection while minimizing field measurements. Beams with different material and cracking parameters were modeled using ABAQUS finite-element analysis software to obtain stiffness values at specified nodes. The resulting database was then used to train an artificial neural network (ANN) model to inversely predict the most probable cracking pattern. The aim is to use the ANN approach to solve an inverse problem where a unique analytical solution is not attainable. Accordingly, simple span beams with three, five, seven, and nine stiffness nodes and a single crack were modeled in this work. To confirm that the ANN approach can characterize the logic within the databases, networks with geometric, material, and cracking parameters as inputs and stiffness values as outputs were created. These networks provided excellent prediction accuracy measures (R2 values>99%). For the inverse problem, the n...
GEOMETRIC OPERATIONS AND THE η-INVARIANTS OF HYPERBOLIC LINKS

In this note we study how the η-invariant of a hyperbolic knot or link behaves under various geometric cuttings and pastings. Among other applications, we show that such an invariant is preserved under mutation and can be used to distinguish many links with homeomorphic complements.
A direct measurement of the rotational relaxation time in CO2

Abstract The rotational relaxation time in CO 2 was measured by observing the gain of a single rotational-vibrational transition as a function of time following the onset of a Q -switched pulse on a neighboring transition. Evidence for rotational selection rules was found.
Synthetic Polyphosphonates, Polyphosphates, and Phosphonocarboxylates as Allosteric Effectors of Hemoglobin

Abstract Synthetic phosphonocarboxylates, diphosphonates, polyphosphates, and some triphosphonic acids were studied as effectors in the binding of dioxygen to human hemoglobin. Ethane-1,2-diphosphonic acid, and triphosphate anion were strong effectors.
Dipyrrinone imines: controlling self-association

We report the synthesis of three new dipyrrinone imine analogues and the characterisation of their self-association properties. Based on vapour pressure osmometry and nuclear magnetic resonance studies, placing the imine functional group at C(9) of the dipyrrinone disrupts the native self-association of the dipyrrinone core in a manner that correlates with the conformational A-value of the imine N-substituent.
2003 American Urological Association Gallup survey: physician practice patterns, cryosurgery/brachytherapy, male infertility, female urology and insurance/professional liability.

Purpose: The Health Policy Survey and Research Committee of the American Urological Association and the Gallup Organization have performed 10 surveys of American urologists since 1992 for the purpose of assessing demographics and practice patterns. The results of the 2003 survey are presented. Materials and Methods: A random sample of 510 urologists who have completed urological residencies was interviewed by telephone in February 2003. Major content areas were physician practice patterns, cryosurgery/brachytherapy, male infertility, female urology and insurance/ professional liability. Results: Urologists are older, staying in practice longer and planning to retire later than ever before. Urologists are also seeing more patients in the office every year. Most urologists treat male infertility and female voiding dysfunction. Conclusions: American urologists are older, working harder and planning on continuing to do so for longer than in any year sampled in the last decade.
Millimeter-scale microrobots for wafer-level factories

Current top down manipulation systems used in micro and nanomanufacturing are many orders of magnitude larger than the parts being handled, leading to difficult tradeoffs between their precision, throughput and cost. This paper presents recent research progress in the manufacturing of millimeter sized robotic positioning technology that allows combining high precision with high throughput along with other application-specific requirements such as strength, dexterity, and work volume. The first robot type is the ARRIpede microcrawler, and we describe recent progress in microrobot packaging and backpack electronics leading to its untethered operation. Precision measurements describing the ARRIpede motion resolution and repeatability are reported. The second microrobot called the Articulated Four Axes Microrobot (AFAM) is a 3D dexterous micromanipulator robot, and we describe nanoindentation experiments using SPM tips mounted on the microrobot. By combining positioning data obtained using laser interferometers and SEM imaging of nanoindentation data, precision metrics such as accuracy, repeatability and resolution of the AFAM robot are determined. Using these two microrobots as basic positioning and manipulation units, we propose a concept for a nanoassembly module, or a so-called wafer-level factory.
Online learning for quality-driven unequal protection of scalable video

Video packet losses affect perceived video quality non-uniformly due to several factors related to video encoding such as inter-frame coding and motion compensation as well as due to psycho-visual perception of natural scenes with unequal motion. This motivates protecting video packets unequally based on their loss visibility. This paper proposes an adaptive online algorithm for unequal error protection driven by two key motivations: On one hand, for real-time video, where a video sequence is not pre-encoded, an offline approach is infeasible and determining the unequal protection levels to maintain a target video quality level must be performed online. On the other hand, an online approach enables adapting to scene changes as well as changes in video temporal and spatial characteristics. The proposed online algorithm uses local linear regression to learn the mapping between packet losses from each scalable video layer and quality degradation without assuming an underlying statistical model. The notion of locality captures the similarity in video scene characteristics as well as proximity in time. The algorithm provably guarantees an average target video quality level and converges rapidly to a stable solution. Furthermore, it provides a bias/variance tradeoff between factual estimation of loss visibility and fine adaptation to the changing video temporal characteristics.
Robust Management of Motion Uncertainty in Intensity-Modulated Radiation Therapy

Radiation therapy is subject to uncertainties that need to be accounted for when determining a suitable treatment plan for a cancer patient. For lung and liver tumors, the presence of breathing motion during treatment is a challenge to the effective and reliable delivery of the radiation. In this paper, we build a model of motion uncertainty using probability density functions that describe breathing motion, and provide a robust formulation of the problem of optimizing intensity-modulated radiation therapy. We populate our model with real patient data and measure the robustness of the resulting solutions on a clinical lung example. Our robust framework generalizes current mathematical programming formulations that account for motion, and gives insight into the trade-off between sparing the healthy tissues and ensuring that the tumor receives sufficient dose. For comparison, we also compute solutions to a nominal (no uncertainty) and margin (worst-case) formulation. In our experiments, we found that the nominal solution typically underdosed the tumor in the unacceptable range of 6% to 11%, whereas the robust solution underdosed by only 1% to 2% in the worst case. In addition, the robust solution reduced the total dose delivered to the main organ-at-risk (the left lung) by roughly 11% on average, as compared to the margin solution.
Oculopharyngeal dystrophy: Ultrastructure of muscles distant from the primary myopathy

The pectoral and psoas muscles from a 72-year-old man afflicted with oculopharyngeal muscular dystrophy were processed at autopsy for electron microscopy. The ultrastructural analyses of the pectoral muscle showed myofibrils which exhibited Z line streaming and a general breakdown in the organization of the sarcomere. In addition, some of the myofibrils displayed sites of degeneration at the center of the A band. The changes in the psoas muscles which are distant from the primary myopathic loci of oculopharyngeal muscular dystrophy were more extensive than that seen in the pectoral muscle. Control tissues showed intact myofibrils and little postmortem alteration.
Relativistic Heavy-Ion Collider (RHIC) physics overview

The results from data taken during the last several years at the Relativistic Heavy-Ion Collider (RHIC) will be reviewed in the paper. Several selected topics that further our understanding of constituent quark scaling, jet quenching and color screening effect of heavy quarkonia in the hot dense medium will be presented. Detector upgrades will further probe the properties of Quark Gluon Plasma. Future measurements with upgraded detectors will be presented. The discovery perspectives from future measurements will also be discussed.
Gibberellins and Stem Growth in Arabidopsis thaliana (Effects of Photoperiod on Expression of the GA4 and GA5 Loci)

Arabidopsis thaliana (L.) Heynh. is a quantitative long-day (LD) rosette plant in which stem growth is mediated by gibberellins (CAs). Application of GAs to plants in short-day (SD) conditions resulted in rapid stem elongation and flower formation, with GA4 and GA9 being equally effective, and GA1 showing lower activity. The effects of photoperiod on the levels of endogenous GAs were measured by combined gas chromatography-mass spectrometry with selected ion monitoring. When plants were transferred from SD to LD conditions there was a slight decrease in the level of GA53 and an increase in the levels of C19-GAs, GA9, GA20, GA1, and GA8, indicating that GA 20-oxidase activity is stimulated in LD conditions. Expression of GA5, which encodes GA 20-oxidase, was highest in elongating stems and was correlated with the rate of stem elongation. By contrast, GA4, which encodes 3 beta-hydroxylase, showed low expression in stems and its expression was not correlated with the rate of stem elongation. We conclude that stem elongation in LD conditions is at least in part due to increased expression of GA5, whereas expression of GA4 is not under photoperiodic control.
Resolution of an infection with Leishmania braziliensis confers complete protection to a subsequent challenge with Leishmania major in BALB/c mice.

Both Leishmania major and L. braziliensis induce cutaneous leishmaniasis in BALB/c mice. Whereas BALB/c mice die of infection with L. major, they cure an infection with L. braziliensis. We report here that after curing an infection with L. braziliensis, BALB/c mice are resistant to challenge with L. major. When challenged with L. major, L. braziliensis pre-treated BALB/c mice mounted a delayed-type hypersensitivity response to L. major and produced high amounts of interferon-g (IFN-g ) but low amounts of interleukin-4. The IFN-g produced by the L. braziliensis pre-infected mice was involved in the protection seen against L. major challenge since treating the mice with a neutralizing anti-IFN-g abrogated the protection. This suggests that cross-reactive antigen epitopes exist between L. braziliensis and L. major and that pre-infection with L. braziliensis primes BALB/c mice to epitopes on L. major that can elicit a protective Th1 response to the parasite.
Stochastic dynamic programming: Caution and probing

The purpose of this paper is to unify the concepts of caution and probing put forth by Feldbaum [14] with the mathematical technique of stochastic dynamic programming originated by Bellman [5]. The decomposition of the expected cost in a stochastic control problem, recently developed in [8], is used to assess quantitatively the caution and probing effects of the system uncertainties on the control. It is shown how in some problems, because of the uncertainties, the control becomes cautious (less aggressive) while in other problems it will probe (by becoming more aggressive) in order to enhance the estimation/identification while controlling the system. Following this a classification of stochastic control problems according to the dominant effect is discussed. This is then used to point out which are the stochastic control problems where substantial improvements can be expected from using a sophisticated algorithm versus a simple one.
Improvement in the Control Aspect of Laser Frequency Stabilization

Flight Electronics Division of Langley Research Center is developing a speceflight experiment called "Stabilized Ultra-Narrow Linewidth Laser-in-Space Technology Experiment" The scientific objective of the project is to explore the fundamental limits on frequency stability using a FM laser locking technique on a Nd:YAG non-planer ring oscillator in the vibration free and microgravity environment of space. This paper focuses on the control aspect of the laser frequency stabilization. The problem has been defined, role of feedback control in frequency stabilization has been established. The parameters of the discrete controller replacing the analogue controller has been determined.
Dispersive spread of virtual sources by asymmetric X‐ray monochromators

The principles of the virtual source spread (spatial broadening) phenomenon induced by angular dispersion in asymmetric X-ray Bragg reflections are illustrated, from which the virtual source properties are analyzed for typical high-resolution multiple-crystal monochromators, including inline four-bounce dispersive monochromators, back-reflection-dispersion monochromators and nondispersive nested channel-cut monochromators. It is found that dispersive monochromators can produce spread virtual sources of a few millimetres in size, which may prevent efficient microfocusing of the beam as required by inelastic X-ray scattering spectroscopy and other applications. Possible schemes to mitigate this problem are discussed. The analyses may provide important guidelines for designing and optimizing modern high-precision synchrotron X-ray optics and beamline instrumentation for spectroscopy, imaging and nanofocusing applications.
Persistent pediatric obstructive sleep apnea and lingual tonsillectomy

Objective: To describe a new method and the indications for lingual tonsillectomy with endoscopy and coblation, and to document its utility for treating children with persistent obstructive sleep apnea after previous tonsillectomy and adenoidectomy.Study Design and Setting: Case series with chart review in a tertiary pediatric medical center.Subjects and Methods: Twenty-six patients aged 3 to 20 met the inclusion criteria of polysomnography-proven persistent obstructive sleep apnea after tonsillectomy and adenoidectomy, as well as diagnosis of lingual tonsillar hypertrophy made by flexible fiberoptic sleep endoscopy. Endoscopic-assisted coblation lingual tonsillectomies were performed between June 2005 and January 2008. Preoperative and postoperative nocturnal polysomnogram data were paired and analyzed statistically.Results: Statistically significant reductions in the respiratory distress index (RDI) were seen when preoperative and postoperative data were compared (mean, 14.7 vs 8.1). There were similar ...
Circular dichroism of the alkyl amino acids in the vacuum ultraviolet.

The circular dichroism and absorption for five alkyl amino acids as zwitterions has now been measured to 160 nm. Two bands are found, the nπ* at long wavelengths and ππ* at short wavelengths. In an effort to extract conformal information from the circular dichroism measurmenths, the circular dichroism spectra for these molecules is calculated using an independent systems apporach. It is found that the signs calculated using these methods are quite reliable, but that reliable magnitudes must await more accurate data to use in the calculations. Comparing the signs for both the measured and calculated circular dichriosm it if possible to determine the region inhabited by the carboxylate anion chromophore of these amino acid zwitterions. The greatest failure of the calculations is that thay are unable to explain the sigmoidal shape of the nπ* transition in proline. The problems facing workers trying to make calculations to relate circular dichroism measurements to conformation are discussed.
Bacterial Endotoxins in the Environment

DURING an evaluation of the Limulus lysate assay procedure1–6 for the detection of Gram negative endotoxins, deionized water was found to be contaminated with endotoxins. Endotoxins were also present in samples of New Orleans tap water, which comes from deep levels of the Mississippi River. To appreciate the environmental distribution of endotoxins, studies were undertaken to compare the Gram negative endotoxin content of New Orleans water with that of other cities, as well as endotoxin distribution in various beverages and biological fluids.
Smallholder Irrigation as a Poverty Alleviation Tool in Sub-Saharan Africa

Summary Promotion of smallholder irrigation is cited as a strategy for enhancing income generation and food security for sub-Saharan Africa’s poor farmers, but what makes this technology a successful poverty alleviation tool? In the short run, the technology should pave the way for increased consumption, asset accumulation, and reduced persistent poverty among users. Over the longer run, it should lead to institutional feedbacks that support sustained economic development and nutritional improvements. Our conceptual model and review of case studies reveal the importance of three sub-components of irrigation technology—access, distribution, and use—and the ways in which the design of the technology itself can either bridge, or succumb to, institutional gaps. These critical features are illustrated in an experimental evaluation of a solar-powered drip irrigation project in rural northern Benin, which provides a controlled study of technology impacts in the Sudano-Sahel. The combined evidence highlights the technical and institutional requirements for project success and points to two important areas of research in the scale-up of any small-scale irrigation strategy: the risk behavior of water users, and the evolution of institutions that either support or obstruct project replication over space and time.
Expression of the bovine oestrogen receptor-β (bERβ) messenger ribonucleic acid (mRNA) during the first ovarian follicular wave and lack of change in the expression of bERβ mRNA of second wave follicles after LH infusion into cows

Abstract In a previous study, the ERβ cDNA protein-coding region was utilised to clone bovine ERβ. The objectives in this study were to examine (1) ERβ mRNA expression in ovarian follicles throughout the bovine first follicular wave, and (2) effect of LH infusion into cows on bERβ mRNA expression during the second follicular wave. In experiment 1, heifers (4–5 per time point) were ovariectomized at 12, 24, 36, 48, 60, 72, 84, 96, 144, or 216 h after emergence of the first follicular wave after oestrus. In experiment 2, saline or LH was pulsed hourly (computer-controlled syringe pump) into cows (n=31; 5–6 per treatment) at wave emergence for 2 or 4 days: wave 1-saline (W1S), wave 2-saline (W2S), or wave 2-LH (25 μg/h; W2LH). Ovaries were removed on day 2 or day 4 after wave emergence. Follicles, 2–19 mm in size, were dissected, frozen, and stored at −80°C for in situ hybridisation with two bERβ cRNA probes. Expression of bERβ mRNA was localised in granulosa cells of healthy follicles. In experiment 1, bERβ mRNA expression did not change with time points of the wave showing no association of bERβ mRNA expression with follicular selection and dominance. However, bERβ mRNA expression decreased with increase in size of all follicles. Expression of bERβ mRNA was greater in very small follicles (2–4 mm) than in large (≥9 mm) follicles. In experiment 2, expression of bERβ mRNA in follicles did not differ either between W1S and W2S or between W2S and W2LH. In summary, bERβ mRNA expression decreased with increasing follicular size. However, neither stage of the wave (selection or dominance), nor pulsatile infusion of LH influenced bERβ mRNA expression.
Why is there a seniority system? To solve an agency problem

It is generally recognized that principals and agents both have an incentive to minimize shirking, and that this is often accomplished by entering into long term relationships in which the agent is offered rewards that increase with seniority. This paper considers that the congressional seniority system may exist as a means of insuring that representatives (agents) are faithful to the demands of constituents (principals). The unique feature of the seniority system, that tenure is rewarded with increasing power rather than increasing pay, is explained as a consequence of the need for each group to make credible commitments to the other. Rules changes adopted by the House of Representatives in the mid 1970s are used to test the impact of alternative rules on election outcomes.
Cloning and light-dependent expression of the gene coding for the P-protein of the glycine decarboxylase complex from peas

The glycine decarboxylase multienzyme complex (EC 2.1.2.10) is located in the mitochondrial matrix and catalyzes a key reaction of the photorespiratory C-2 cycle of plants. The light-dependent control of the synthesis of the P-protein of this complex in pea (Pisum sativum cv. Alaska) leaves was studied using a partial (0.7 kb) cDNA clone. The size of the P-protein mRNA detected by this probe was 3.5 kb. When the mRNA hybrid selected by this probe was translated in vitro, a protein that migrated in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with an apparent molecular mass of 114 kDa was formed. This protein could be immunoprecipitated with the P-protein-specific antibody. The mass of the mature P-protein on SDS-PAGE is 100 kDa. This suggests the presence of a presequence used to direct the protein to the mitochondrial matrix. Analysis of the concentration of P-protein mRNA showed an approximately 5-fold increase in the abundance of this transcript in light-grown as compared to dark-grown pea seedlings. The time course for the production of P-protein mRNA following exposure of dark-grown peas to white light was compared to that for the H-protein of glycine decarboxylase, the small subunit of ribulose bisphosphate carboxylase/oxygenase, and the chlorophyll a/b binding protein. All 4 mRNAs accumulated with similar kinetics where they remained low during the first 3 h of illumination, increased about 5-fold during the next 8 h, and then maintained a steady state over the next 12 h.
Theoretical demonstration of stabilization of active modelocking in quantum cascade lasers with quantum coherent absorption

We theoretically incorporate quantum coherent absorption in an actively modelocked quantum cascade laser. The laser self-starts from initial quantum noise and produces a stable train of modelocked pulses at high pump powers.
Tickling Memory T Cells

Viruses cause immediate induction of type I interferons (which include IFN-alpha and IFN-beta). These IFN I cytokines limit spread of the virus until antigen-specific responses can fully control the infection. A report by Tough et al . (p. 1947) show that these IFN I have another function: They also augment the proliferation of T cells, including a subset of T cells that may mediate long-term immunological memory. In his Perspective, Ahmed discusses the possible contribution of this bystander effect of IFN I to immunological memory.
Free interactions, hierarchical structure: Factors explaining replies attraction in online discussions

Given the opportunity to interact freely, individuals conform to a structure, in which a few actors attract a large and disproportionate number of ties or relationships. Drawing from literature on preferential attachment and scholarship about online discussions, this study examines patterns of replies, which are one aspect of the disproportionate attraction of replies in forums, as predicted by two factors: number of existing replies and content of posted messages. In two 2X2 experimental designs conducted via a custom developed online discussion platform, 198 subjects participated. Findings show an interaction, where the number of replies increased replies attraction only for the high–interest messages, illustrating the balance between the individual and group dynamics levels in evoking discussions.
Strategic Information System Plans in Nations Around the World

Strategic information systems planning (SISP) literature addresses the importance of measuring both broad externally validated societal measures of organizational outcomes, while at the same time assessing organization specific metrics that speak to an institution’s ability to deliver specific outputs. Accordingly, this article explores literature for strategic management in the public sector, SISP, and digital government and applies a strategic planning framework along with analyzing national SISP plans for information technology or electronic government. The research finds that countries are developing both strategic and operational goals that have managerial and governance implications.
A Comparison of a Spray Penetration Correlation by an Optical Obscuration Technique to Other Correlations Obtained by Different Techniques

Previous studies dealing with sprays have used a variety of techniques to determine spray droplets and spray penetration. In particular, the sedimentation tower method and the liquid immersion sampling technique were most popular. However, in these techniques sampling is done after spray formation is complete. The completion time of spray formation appears to vary with the conditions of injection and ambient factors, thus making measurements under transient conditions during injection difficult. A pulsed Malvern drop-size analyzer, based on Fraunhofer diffraction, was utilized to determine spray penetrations of diesel fuels under different conditions of injection, along with the effects of fuel properties. In these study, the spray is formed by injecting a calibrated amount of fuel into air. A two mm diameter collimated beam illuminated a cylindrical volume perpendicular to the axis of the fuel spray, and its attenuation was recorded and stored on the oscilloscope. With the optical measurement being synchronized to the needle lift of the injector, the output of the needle lift transducer and the optical signal was recorded simultaneously. Thus, the arrival and the duration of the spray at various positions along its axis were measured. A spray penetration correlation is obtained, and is compared to other existing correlations in the literature.Copyright © 2002 by ASME
Characterization of intracellular esterase a from Bacillus subtilis

Esterase A (EC 3.1.1.1) obtained by sonic disruption of Bacillus subtilis SR22 (spoA12, trpC2) was purified approximately 400-fold by differential chemical and heating precipitation, DEAE-cellulose chromatography, and Bio-Rad P-150 gel filtration chromatography, with an overall yield of 59%. The purified enzyme hydrolyzed both aliphatic and aromatic acetate esters at substrate concentrations of 0.25 M but did not hydrolyze amino acid esters. Aliphatic alcohols did not inhibit the hydrolysis of p-nitrophenyl acetate; the most potent inhibitors of esterase activity were mercuric chloride, diisopropylfluorophosphate, eserine, and sodium fluoride.
Structure-function analysis of Frizzleds

Frizzleds, cell surface receptors that mediate the actions of Wnt ligands on early development, are heptahelical (based upon hydropathy analysis) and couple to heterotrimeric G proteins. The primary structure of all ten mammalian Frizzleds display many landmarks observed in virtually all G protein-coupled receptors, including an exofacial N-terminus that is N-glycosylated, the presence of seven hydrophobic transmembrane segments predicted to form alpha-helixes, and three intracellular loops as well as a cytoplasmic, C-terminal tail that harbor suspected sites for protein phosphorylation. Prediction of the G proteins to which Frizzleds mediate signaling based upon a bioinformatic analysis of the primary sequence of the intracellular domains are in good agreement with functional screens in Drosophila, zebrafish, and mouse models of development, e.g., predicting Frizzled-1 to interact with members of the Gi/Go protein family. Likewise various Wnt signaling pathways are sensitive to treatment with pertussis toxin and knock-down of specific G protein alpha-subunits. Homology among the sequences encoding the cytoplasmic domains of human Frizzleds is high and the various Frizzleds can be segregated into subsets predicted to share some common downstream signaling elements. Among different species, homologies can reveal conservation of signaling to cognate G protein partners. Additionally, cytoplasmic domains of the prototypic beta2-adrenergic receptor can be substituted with those from either Frizzled-1 or Frizzled-2 to create chimeric receptors that are activated by beta-adrenergic agonists, yet signal with high fidelity to the Wnt/beta-catenin and Wnt/Ca2+, cyclic GMP pathways, respectively, regulating key aspects of early development. The nature of Frizzled-based signaling complexes, their temporal assembly, and spatial distribution via scaffold protein remains to be elucidated, as does whether or not these Wnt receptors display agonist-induced desensitization, internalization, and re-cycling to the cell membrane.