cssi/SciSciGPT-SciSciNet huggingface dataset:
Beyond Writing Next: A Discussion of Writing Research and Instructional Uncertainty

Drawing on their experiences as high school writing instructors, researchers, and teacher trainers, David Coker and William Lewis examine an often overlooked dimension of adolescent literacy: writing proficiency. The authors explore recent research on the skills and strategies students need in order to write with competence and describe analyses of interventions that help students attain writing mastery. They also address divisions and gaps in the field of writing research and instruction and offer suggestions for overcoming these rifts in order to advance understanding of adolescent writing development and effective writing instruction.
Laquinimod delays and suppresses nephritis in lupus-prone mice and affects both myeloid and lymphoid immune cells.

Objective Lupus nephritis depends on autoantibody deposition and activation of multiple immune cell types that promote kidney inflammation, including lymphocytes and monocyte/macrophages. Laquinimod, currently in clinical trials for multiple sclerosis and lupus nephritis, reduces infiltration of inflammatory cells into the spinal cord in experimental autoimmune encephalomyelitis. Activated monocyte/macrophages infiltrate the kidneys during nephritis in systemic lupus erythematosus (SLE). We undertook this study to determine whether using laquinimod to reduce monocyte/macrophage-driven tissue damage as well as to alter lymphocytes in SLE nephritis could have greater therapeutic benefit than current treatments that primarily affect lymphocytes, such as mycophenolate mofetil (MMF). Methods To test laquinimod efficacy, we used the (NZB × NZW)F1 mouse model of SLE, in which disease manifests as nephritis. Preventive and therapeutic studies were performed to determine whether laquinimod could prevent or delay nephritis, as measured by proteinuria, serum creatinine, survival, and renal pathology. Spleen and kidney leukocyte populations and suppression assays were analyzed by flow cytometry. Results Laquinimod prevented or delayed lupus manifestations at levels equal to or better than MMF. Laquinimod treatment was associated with reduced numbers of monocyte/macrophages, dendritic cells, and lymphocytes, as well as with induction of myeloid-derived suppressor cells in spleens and kidneys. Laquinimod suppressed macrophage-secreted tumor necrosis factor α and induced production of interleukin-10 (IL-10). In addition, laquinimod suppressed interferon-γ and IL-17 production by lymphocytes and down-regulated expression of activation/costimulatory markers on antigen-presenting cells. Conclusion The effects of laquinimod on myeloid and lymphoid cells may contribute to improvements in (NZB × NZW)F1 mouse survival, proteinuria, and glomerulonephritis. Future development of laquinimod as a therapeutic agent for lupus nephritis is promising.
Sleep behaviour in preterm children from birth to age 10 years: a longitudinal study.

Aim: To study clinically relevant aspects of sleep behaviour in preterm children in comparison to term children. Methods: Longitudinal sleep behaviour data were collected prospectively by structured interviews in 130 preterm and 75 control term children from birth to age 10 y. Results: No significant differences in sleep duration (time in bed per 24 h), bedsharing, night wakings, bedtime resistance and sleep-onset difficulties were found between preterm and term children. Conclusion: Sleep behaviour does not differ between preterm and term children from birth to age 10 y, indicating that prematurity or neonatal intensive care experience does not significantly affect sleep in the first 10 y of life.
A chirp PWM scheme for brushless DC motor drives

A novel chirp pulse width modulation (CPWM) scheme is proposed to improve the performance of AC motor drives by reducing electromagnetic interference. The proposed CPWM is operated on the chirped waveform that has a specified bandwidth defined within a minimum and a maximum switching frequency. The design procedure of CPWM that includes selecting the chirp bandwidth and the PWM frequency sweeping time period is presented and analyzed. Then the theoretical analysis is done for both the chirped and non-chirped waveforms. Optimum EMI reduction scheme is developed from the theory. The computer simulation and experimental results verify that the proposed CPWM method has better performance in comparison to PWM with fixed frequency.
Depression and insomnia: questions of cause and effect

Chronic insomnia is a risk factor for the development of psychiatric disorders, including depression, as well as a prodrome of major depressive episodes, a consequence or complication of depression that often persists beyond the clinical episode, and a prognostic indicator of long-term illness course and treatment response. In addition, sleep is physiologically abnormal in persons at risk for depression; for example, shortened REM sleep latency is present not only during clinical episodes of depression, but also before the clinical episode in subjects at risk for depressive illness. Although insomnia usually disappears as depression is treated, it may persist, indicating heightened vulnerability to depressive relapse or recurrence. Physiological changes in sleep related to depression correlate with the likelihood of response to psychotherapy alone and may also identify which patients are unlikely to do well with psychosocial treatment and, therefore, to need somatic therapy in order to preserve recovery. Electroencephalographic (EEG) sleep changes also correlate with the speed of response and with the brittleness or durability of response (i.eprobability of relapse or recurrence). These observations suggest a close relationship between the regulation of sleep and the regulation of mood. The importance of this relationship is further underscored by recent brain imaging studies of sleep and sleep deprivation in patients with major depression. For example, therapeutic sleep deprivation (TSD) may serve as both a catalyst of rapid antidepressant activity and as a probe of treatment resistance. TSD's effects on brain metabolic rates, especially in limbic areas, may correlate with a therapeutic response to a night of sleep loss and to antidepressant medication. Finally, treating chronic insomnia with newer selective serotonin reuptake inhibitor (SSRI) antidepressant medication may represent an opportunity for preventing complications of insomnia, including depressive illness.
Utilizing software engineering to improve software process capabilities within the Biological Engineering Research Unit

Abstract This paper presents some changes implemented in the Biological Engineering Research Unit (BERU) to improve the development and support of software used in our research. BERU uses a diverse collection of computers covering everything from hand-held dataloggers to UNIX 1 workstations. Most of our computer efforts are aimed at collecting, storing and analyzing research data. Software engineering concepts provide a roadmap to help recognize problems to focus efforts on improvements. The use of data modeling, configuration management, project planning, and oversight, quality assurance and other software-related improvements addressed by the BERU are presented as examples of how software engineering can be used to improve research efforts.
Comparison of two flow surveys above stalled wings

A laser velocimeter (LV) surveyed the flow above two stalled wings. Each wing was tested in a different wind tunnel at different Mach numbers. The low-Mach-number test had an angle of attack of 19.4 deg, 0.15 Mach number, and 1 x 1,000,000 Reynolds number. The mean velocities above the reversed, separated flow were closely modeled by error function profiles. Thus, the flow resembled a turbulent free-shear layer. The high-Mach-number test had an angle of attack of 19.5 deg, 0.49 Mach number, and 1,400,000 Reynolds number. A series of strong, discrete vortices were shed from the airfoil crest at regular intervals. Both tests demonstrated the importance of the unsteady part of the velocities.
H2S/Cu(111): A model study of sulfur poisoning of water-gas shift catalysts

The interaction of H2S with Cu(111) has been studied with XPS, AES, ISS and LEED; and the effects of sulfur adatoms upon the kinetics of the medium-pressure water-gas shift reaction over Cu(111) have been measured. At 120 K, H2S adsorption is partially molecular. By 200 K, some of the H2S desorbs and the rest dissociates to produce sulfur adatoms bonded on top of the Cu(111) surface. The surface saturates at room temperature in a ( 7 x 7 ) structure (θs=0.43) characteristic of a nearly close-packed sulfur overlayer, very similar to layers in (111)-oriented Cu2S. Sulfur adatoms are quite stable to heating in vacuum or H2, with a reaction probability for removal per H2 collision with the surface of ≤10−9 at 636 K. The rate of the forward water-gas shift reaction (H2O+CO→H2+CO2) decreases linearly with sulfur coverage as (1–2.6θs). This poisoning is attributed to steric blocking by the sulfur adatoms of the sites required for dissociative water adsorption. The site ensemble required for this step is small (1–2 Cu atoms). The well-known sensitivity of shift catalysts to sulfur poisoning is discussed in the light of these results.
Special session on design & failure: How philosophy and belief impact design education

This special session presents applications of the philosophy of engineering to the understandings of engineering design. The philosophical basis of engineering provides particular insight into framing and interpreting design experiences. This interactive sessions/workshop aims to discuss and analyze engineering design and its place in engineering education. This includes examining perspectives from practitioners and educators on engineering design, and how these can better shape priorities and learning experiences in undergraduate engineering education.
Black woman professor—White university

Abstract Black people, as a group, have been the victims of exclusion in almost all areas of the dominant American cultural life. Black women, in particular, have suffered because of race and sex. The result of these oppressions has been a general cultural silence and invisibility of all black people. Challenges to the racial status quo reached momentous dimensions in the 1960s—the era of the black revolution, and touched all areas of the national life in the U.S.A. However, when the smoke cleared, black women discovered that despite their efforts in the struggle, few of them reaped rewards. In the wake of the women's liberation movement that followed, the general consensus among women of color was that black meant black men and women meant white women. This is an unsatisfactory state of affairs, and one which black women have vowed to fight against. The university is one of the arenas for this confrontation. This paper looks at the experiences of one black woman in a prestigious Midwestern university and documents the nature of her experiences as a double minority. She voices the opinion that black women intend to struggle on to their rightful places in the academy. They can't go back, and they aim to stay.
Multiple Sourcing Alternatives Using Nearly Optimal Programming

Abstract A linear programming (LP) model representing multiple sourcing is investigated. The LP represents the allocation of order quantity for three potential vendors. The optimal solution uses two of three vendors, with 75% of the order being supplied by the second vendor and the remaining 25% by the third. Nearly optimal programming (NOP), a form of sensitivity analysis not generally covered in management science or operations research texts, is applied to the LP model. We show that with only minor modifications to the model, a variety of new solutions can be generated that represent distinct solutions from the optimal. These distinct solutions provide the manager and the business student with alternatives, which could be useful if there are problems with specific vendors.
Quality measures in health care.

This article discusses measurement quality in health care. The authors attempt to answer the following questions: why measure quality, and what will quality measurement do? The current quality measurement system is described including definitions of the measurable aspects of health care and current measurement tools. Finally, suggested benchmarks for various health care measurements are included.
Letter to the Editor: Intrahepatic Portal Tracts Abnormalities Associated with Anomalous Venous Connections

(1997). Letter to the Editor: Intrahepatic Portal Tracts Abnormalities Associated with Anomalous Venous Connections. Pediatric Pathology & Laboratory Medicine: Vol. 17, No. 2, pp. 331-332.
Behavioral effects of chronic cocaine treatment in the week-old rat pup

Abstract Chronic treatment of adult animals with cocaine results in sensitization to some behavioral effects and tolerance to others but there are few reports on the effects of chronic stimulants during early development. The present experiments assessed the development of cocaine-induced alterations in locomotor activity and separation induced ultrasonic vocalization, a fundamental behavior of infant rats. The first study demonstrated a dose dependent suppression of ultrsouns in naive pups at 7 days of age that lasted at least 60 min and that was accompanied by a dose dependent increase in locomotion. To assess chronic effects, pups were injected with cocaine (5.0–30.0 mg/kg) twice daily from ages 1 to 7 days and then tested at 7, 8 and 10 days of age for vocalization in response to isolation from the dam and littermates. There were minimal effects on baseline levels of crying, but following chronic treatment with cocaine, pups showed generally higher level of ultrasounds when tested with an acute challenge of cocaine at 7 and 8 days of age. In chronically treated pups locomotor activity was increased during baseline tests. At 10 days of age, 3 days after the last treatment with cocaine, in the highest dose treatment condition, there was an exaggerated reduction of ultrasounds when tested with a littermate. The results demonstrate that chronic exposure to cocaine during early development disrupts the normal regulation of a developmentally important socially mediated behavior.
Biodeterioration of the biosphere: Where does wildlife damage management stand?

Degradation of the biosphere with the associated loss of biological integrity is the most critical issue facing humankind today. Wildlife damage management expertise is critically needed in addressing this issue head-on from both traditional and non-traditional approaches. The profession offers a unique combination of both wildlife management training and damage management experience, which helps in understanding a variety of conservation perspectives, especially on private land. Because relationships between damage management and sustainability are often not clearly recognized, and because many traditional wildlife damage management activities are criticized as inappropriate or not needed, we suggest a reassessment of our vision for the future of the profession to include biosphere sustainability as a basic guiding principle. Implications could include greater emphasis in some areas and reassessment in others such as prairie dog management. Greater emphasis might be placed on native ecosystems, impacts of invasive exotic species or overabundant native species, fragmented habitats, nest pests, and, particularly, sustainable agricultural issues. A shift toward greater service to biosphere sustainability will bring both rewards and responsibilities. It will also strengthen the relevance of wildlife damage management and enhance the credibility of the profession for the future.
Thiol-disulfide interchange between cystine and N-2-mercaptoethyl-1,3-diaminopropane as a potential treatment for cystinuria

Abstract The radioprotective compound WR2721 is a thiophosphate, which, when administered orally, is activated at the acid pH of the stomach to its free thiol (MDP). The free thiol is a mucolytic compound which acts via the reduction of disulfide bonds of mucin molecules. An equimolar mixture of MDP and cysteine, in urine at pH 6.0 and 37°C, when oxidized by molecular oxygen, preferentially forms the soluble mixed disulfide between MDP and cysteine. the disulfide cystine will undergo thiol-disulfide interchange with MDP; as a result, cystine crystals are effectively dissolved. Moreover, in the presence of catalytic amounts of free thiol, the disulfide of MDP will undergo thiol-disulfide interchange with cystine to dissolve cystine crystals. The mixed disulfide of MDP with cysteine is soluble in urine at pH 6.0 and 37°C to at least 100 mg/ml. Chromatographic procedures which permit the analysis of MDP and its mixed disulfide derivatives as MDP-sulfonic acid are described. By these procedures, it was demonstrated that 20% of a single oral dose of WR2721 was excreted as MDP derivatives in the urine of normal volunteers. These procedures will permit the evaluation of WR2721 in the treatment of cystinuria.
Work and water intake and the water need of rats during growth of a tumor.

Abstract Spontaneous water intake of rats with water freely available increases during growth of Walker 256 carcinoma. This increase was totally abolished by coupling to drinking even a minimal work requirement (by imposing various rates of lever pressing as an operant condition of water supply), but there was no concomitant change in growth of tumor or host, or in food intake, and no reduction in excretion of urinary solutes. The increase in water intake is not essential to the water economy of the tumor-bearing animal. Increase in work level coupled to drinking up to approximately 4 times the work of drinking freely available water produced no depression of water intake before tumor transplant and no further depression after tumor transplant. Progressive increase in work level beyond this value further progressively depressed water intake before tumor transplant. This secondary depression of intake was partly reversed during tumor growth by the increase in water necessary to excrete a larger urinary solute load at a reduced urine concentration.
Marital Conflict, Allostatic Load, and the Development of Children's Fluid Cognitive Performance

Relations between marital conflict, children's respiratory sinus arrhythmia (RSA), and fluid cognitive performance were examined over 3 years to assess allostatic processes. Participants were 251 children reporting on marital conflict, baseline RSA, and RSA reactivity (RSA-R) to a lab challenge were recorded, and fluid cognitive performance was measured using the Woodcock–Johnson III. A cross-lagged model showed that higher levels of marital conflict at age 8 predicted weaker RSA-R at age 9 for children with lower baseline RSA. A growth model showed that lower baseline RSA in conjunction with weaker RSA-R predicted the slowest development of fluid cognitive performance. Findings suggest that stress may affect development of physiological systems regulating attention, which are tied to the development of fluid cognitive performance.
Comment on 'What is negative refraction?'

In this rejoinder, I address some of the points raised by McCall, Kinsler and Favaro in their Response to the preceding Comment.
Soft Errors Induced by Energetic Protons

Two types of 4K dynamic RAM devices have been shown to exhibit soft errors when exposed to energetic protons. Considerable variation in sensitivity was found among devices, even those of the same model. For individual devices the soft error cross section increased with proton energy over the range of proton energies of from 18 to 130 MeV. The types of errors observed and their locations in memory were also found to depend on the beam energy.
The relationship between food refusal and social skills in persons with intellectual disabilities

Background Feeding problems are common among individuals with intellectual disabilities. The aim of the current study was to determine the relationship between food refusal and social skills in peo...
Multiscale modeling of protein uptake patterns in chromatographic particles.

A parallel diffusion model is presented to explain an apparent transition in uptake mechanism seen in experimental observations of protein uptake into porous adsorbents. While such models have been...
Analysis of thermal processes: The exponential integral

Thermal processes can often be characterized by peak reaction temperatures, pre-exponentials, and activation energies, as well as by other parameters. Values of the exponential integralEi(−x), or of a related integralI(x), where the numeric argumentx is a function of activation energy and temperature, are essential to the analyses of many of these processes. It is shown that the use of only the first term of the concomitant asymptotic series to approximate these integrals can result in less reliability than the uncertainty in thermal reaction data. Hence, values ofI(x) which are accurate to 4 significant digits over the range ofx from 15 to 50 are presented.
Path-integral formulation of closed strings.

We construct the covariant path integral for the Neveu-Schwarz-Ramond superstring in superspace, with manifest invariance under diffeomorphisms and local supersymmetry transformations. Spin structure is introduced, and the constraints imposed by modular invariance on fermionic string models examined. The critical exponents of the bosonic and fermionic string models in space-time dimensions less than the critical dimension are obtained for world surfaces of arbitrary topology.
The Effect of Organismic Disadvantage on Allocation Behavior in Children

Equity theory (Adams, 1965) suggests that when persons are asked to divide a given amount of reward between two other persons, one relatively more disadvantaged than the other at performing a task, they will make allocations that are disproportionate to the two persons' performance levels, giving the disadvantaged person a disproportionately larger share and the advantaged person a disproportionately smaller share of the reward. The theory attributes this effect to the allocator's perception that the disadvantaged individual expended a disproportionately greater amount of effort. A group of third- and fourth-graders and a group of seventh-graders were asked to divide rewards between pairs of children that were described to vary in age (“younger” vs. older) or ability (“unskilled” vs. skilled) or that were the “same” in age and ability and that were described to vary (5 vs. 15, or 0 vs. 20 baskets) or to be equal (10 vs. 10 baskets) in performance on a basketball-shooting task. Unlike the group of third- and fourth-graders, the seventh-graders generally made significantly larger allocations to the disadvantaged individuals (“younger” and “unskilled”) than to the “same” individuals, making the largest allocations under the most discrepant performance condition (0 vs. 20). Overall, the results suggested that the equity principle becomes more salient in children as age increases.
Herbivory on Diplacus aurantiacus shrubs in sun and shade

This study tested the hypothesis that carbon allocation to the production of leaf antiherbivore chemicals reflects the intensity of herbivory and interacts with resource allocation to photosynthesis. The amount of herbivory by Euphydryas chalcedona butterfly larvae was measured on Diplacus aurantiacus shrubs growing in different daily solar irradiance regimes. The amount of herbivory sustained by plants was directly related to the degree of solar irradiance the shrubs received and to characteristics which vary with light intensity, e.g. leaf specific weight, but not to leaf resin or nitrogen content. Carbon allocation to the defense of leaf area was marginally related to the light regime, but was not directly related to photosynthetic income.
Time-dependent methods for calculating thermal rate coefficients using flux correlation functions

In this paper we study numerical methods for calculating thermal rate coefficients using flux correlation functions, with the goal of determining optimal methods for producing values with a specified accuracy. In all cases we employ grid based methods for solving the time‐dependent Schrodinger equation in one mathematical dimension for a simple barrier potential function. The solutions are used to determine the propagator matrix elements needed to evaluate the flux correlation functions. Within this framework, we examine (1) several time‐dependent methods for propagating the wave packets, (2) several procedures for evaluating the action of the Hamiltonian on the wave function, (3) the choice of complex time contours for evaluating the rate coefficient expression, (4) alternatives for estimating the initial short‐time evolution of the wave packet (which starts as a δ function), (5) quadrature methods for evaluating the spatial and time integrals appearing in the flux correlation function, and (6) special n...
Nitrogenase activity, photosynthesis, and the degree of heterocyst aggregation in the cyanobacterium Anabaena flos-aquae

The nitrogen-fixing cyanobacterium Anabaena flosaquae Lyngb.) De Breb. exhibited aggregation of heterocysts from different filaments in a eutrophic lake and when grown in unialgal culture. The resulting aggregated filaments formed unialgal flocculent masses having a thickness of several centimeters that apparently resulted from cohesive mucilage surrounding heterocysts. We tested the effects of heterocyst aggregation on nitrogenase activity (NA) and photosynthesis in relation to microscale environmental O2 gradients. The redox indicator 2,3,5-triphenyl tetrazolium chloride showed that aggregated heterocysts had lower intracellular redox potential than those that were dispersed. Microelectrode measurements showed that heterocyst aggregates in actively photosynthesizing flocculent masses were surrounded by a microzone of O2 30% higher than in the surrounding water: dispersed cells exhibited no such elevated O2 microzone. Despite high levels of O2, NA was greater in aggregated than dispersed samples, Microscale irradiance measurements made with a fiber optic light probe showed that 40% of the incident light was absorbed within the first 3 mm of a 1-cm-thick flocculent mass. The microscale irradiance data, together with nitrogenase and photosynthesis versus irradiance data, imply that the ratio of N:C fixation is lowest in filaments on the outside of 1.5–2.0-cm masses and increases toward the center.
SU-GG-T-280: Dose Characteristics and Applications of Optically Stimulated Luminescent Dosimeters in Proton, Electron and Photon Radiotherapy

Purpose: To investigate dosimetricproperties of optically stimulated luminescent detectors (OSLDs) and their application to proton, electron and photonradiotherapy relating to their energy dependence, linearity, reproducibility and use in small field measurements. Method and Materials: The OSLDs used are 0.7 cm diameter, 0.02 cm thick plastic disks containing Al 2 O 3 : C in a light‐tight plastic holder available as InLight/OSL Dot detectors (Landauer, Inc). For the small photon field measurements the sensitive diameter of the detector was reduced to 0.05 cm by making a pin‐hole in the holder. The thermoluminescent detectors were 0.3×0.3 cm2, 0.038 cm thick chips. A micro‐MOSFET dosimeter was used for the small field measurements. A Varian Cl 2100 provided 6 and 18 MV photons and 6–20 MeV electrons. A Philips RT‐250 provided photons from 80–250 kVp. Three proton facilities in the United States provided the proton irradiations. Results: Irradiation of detectors followed by optical bleaching for dose increments of 0.5 Gy from 0.5–4.0 Gy up to 30 Gy showed less than 1% variation in their relative sensitivities. Dose response for the megavoltage photons and electrons was independent of energy while for protons it was 3% less than for 6 MV photons. The response to kilovoltage photons increased inversely with energy from 30–300% relative to 6 MV photons. Supralinearity was observed at doses above 1.5 Gy. Measured output factors, Spc, for 6 MV at 5 cm depth for 0.5×0.5–3.0×3.0 cm2 fields agreed with the other detector measurements. Conclusion: These results demonstrate their potential for applications in megavoltage proton,photon and electron radiotherapy. Their favorable properties include relative energy independence, dose linearity below 1.5 Gy, dose independent relative sensitivity and use in small field dosimetry. Their response variation for kilovoltage photons is due to their higher Z relative to water.
Parameter control, characterization, and optimization in the fabrication of optical fiber near-field probes

Tip diameter and transmission efficiency of a visible-wavelength near-field optic probe determine both the lateral spatial resolution and experimental utility of the near-field scanning optical microscope. The commonly used tip fabrication technique, laser-heated pulling of fused-silica optical fiber followed by aperture formation through aluminization, is a complex process governed by a large number of parameters. An extensive study of the pulling parameter space has revealed a time-dependent functionality between the various pulling parameters dominated by a photon-based heating mechanism. The photon-based heat source results in a temperature and viscosity dependence that is a complex function of time and fiber diameter. Changing the taper of the optical probe can affect transmission efficiency by an order of magnitude or more.
Hypertext vs boolean-based searching in a bibliographic database environment: a direct comparison of seacher performance

The purpose of this study is to carry out a direct comparison of a hypertext-based bibliographic retrieval system with a traditional Boolean-based retrieval system, each using the same database. Novice and experienced searchers were assigned to either a prototype hypertext system called HyperLynx or to a traditional Boolean system and were asked to perform a set of search tasks. The study revealed that the Boolean system performed better than the hypertext system for search tasks with a large number of relevant items. Searcher experience level did not play a significant role for either system. Findings of the study have implications for the design of future information retrieval systems that take advantage of the best features of both approaches for more effective and efficient retrieval of highly structured databases.
pH Dependence of the Photoactive Yellow Protein Photocycle Investigated by Time-Resolved Crystallography

Visualizing the three-dimensional structures of a protein during its biological activity is key to understanding its mechanism. In general, protein structure and function are pH-dependent. Changing the pH provides new insights into the mechanisms that are involved in protein activity. Photoactive yellow protein (PYP) is a signaling protein that serves as an ideal model for time-dependent studies on light-activated proteins. Its photocycle is studied extensively under different pH conditions. However, the structures of the intermediates remain unknown until time-resolved crystallography is employed. With the newest beamline developments, a comprehensive time series of Laue data can now be collected from a single protein crystal. This allows us to vary the pH. Here we present the first structure, to our knowledge, of a short-lived protein-inhibitor complex formed in the pB state of the PYP photocycle at pH 4. A water molecule that is transiently stabilized in the chromophore active site prevents the relaxation of the chromophore back to the trans configuration. As a result, the dark-state recovery is slowed down dramatically. At pH 9, PYP stops cycling through the pB state altogether. The electrostatic environment in the chromophore-binding site is the likely reason for this altered kinetics at different pH values.
Determination of calcium carbonate moisture content by a radioisotope technique.

The transmission of beta particles through calcium carbonate samples with different moisture contents was studied. It was found that the transmission was linearly related to the moisture content.
Origin of Amniotic Fluid Lipids III. Fatty Acids

ConclusionFatty acid analysis of amniotic fluid lipids confirms our previous hypothesis of their multicentric origin. The sources may include fetal lung, plasma, skin, and vernix caseosa, but not m...
Aged Parents and Their Widowed Daughters: a Support Relationship

This study examined the role of social support from parents, as well as other family members, friends and neighbors for the psychological well-being of 98 recent and still grieving widows. The survey results suggest that the effectiveness of the social support provided recent widows is largely dependent upon who is providing it. Aged parents were the must crucial sources of support; even large amounts of support from others, including their own children, was virtually ineffective. This research suggests that more attention should be focused on the important ways middle-aged or older children may depend upon their elderly parents.
Bond character, bond order and the quadrivalency of carbon

Abstract When the chemical bond is treated as a resultant without specific reference to its exact nature, a consistent interpretation of the relationship between the various types of carbon-carbon bonds is possible. The terms bond character, bond order and quadrivalency are considered in the light of this interpretation. It is emphasised that the chemical bond must be regarded as a vector quantity involving both direction and magnitude factors.
Ultrastructure of cephalopod chromatophore organs.

The chromatophore organs of Loligo opalescens are composed of five different types of cells: the chromatophore proper; radial muscle fibers; neuronal processes (axons); glial cells; and chromatophoral sheath cells. The surface of a retracted chromatophore is extensively folded, but upon contraction of the radial muscle fibers it becomes flattened and the folds of the surface disappear. The cell membrane cannot be responsible for the elasticity of the chromatophore as claimed by earlier investigators. The pigment granules are confined within a filamentous compartment (cytoelastic sacculus) throughout the cycle of expansion and retraction. The sacculus decreases in thickness during expansion and increases in thickness during retraction and does not become folded. The elastic properties of the chromatophore are attributed to the cytoelastic sacculus. Primary infoldings of the chromatophore surface are anchored to the sacculus at points called focal haptosomes. The periphery of the sacculus attaches to the plasmalemma of the equatorial part of the chromatophore, opposite the area of attachment of the radial muscle fibers (myochromatophoral junction) by a zonular haptosome. The regular, obliquely striated muscle fibers that expand the chromatophore are associated with axons and glial cell processes. Adjacent muscle fibers may be electrically coupled through close junctions. The entire chromatophore and the muscle fibers are surrounded by sheath cells.
Physiological Effects of Pneumoperitoneum

Since its inception in the early 1980s, laparoscopy has become a widely accepted surgical approach. Smaller incisions impart several clinical benefits such as improved cosmesis, decreased pain, and an earlier return to preoperative activities. Laparoscopy, however, requires the establishment of pneumoperitoneum, which alters certain physiologic functions. We will review the physiologic effects of pneumoperitoneum (Fig. 1).
A simulation study of multiple-load-carrying automated guided vehicles in a flexible manufacturing system

Abstract Although the technology exists for more advanced applications of automated guided vehicles in flexible manufacturing systems, the current employment of these vehicles in material handling generally subscribes to a simple mode of operation : single-load-carrying capacity for each vehicle and unidirectional traffic on each route of the system. Through a simulation programme, this study investigates the effect of several key factors related to the automated guided vehicles on the overall performance of a flexible manufacturing system. These are the number of pallets allowed in the system, the number of vehicles used and the carrying capacity of each and the input and output queue capacities of the machining stations; finally bidirectional traffic is allowed in some routes. The results show that there is a strong interaction among these factors and reveal their combined effects on the throughput from a small flexible manufacturing system. Upon the user's request, the simulation program also provides ...
Sexual Orientation, Sociobiology, and Evolution

Sociobiologists have proposed evolutionary explanations of homosexuality. Such hypotheses assume that the homosexual orientation is a distinct, reifiable trait, rather than an expression of universal sexual and emotional drives. For homosexuality to constitute an evolved trait, it must have a genetic basis. However, there is no reliable evidence that homosexual and heterosexual orientations are caused vy genetic differences. On these and other grounds, we find sociobiological explanations of homosexuality to be implausible and unsupported by evidence. Evolutionary theory provides no guide to morality or ethical progress, nor for appropriate social attitudes toward homosexuality.
Anti-individualism and analyticity

Jessica Brown (1995), following Michael McKinsey (1991), has defended an argument aimed at establishing the incompatibility of anti-individualism and privileged access. The basic idea of the Brown-McKinsey reductio argument is that if anti-individualism is true, then one can come to know some substantive proposition about one's external environment purely by knowing one's own thoughts and reflecting on the consequences of antiindividualism. In Falvey 2000 and McLaughlin & Tye 1998, there are persuasive objections to Brown's defence of such an argument. Her subsequent response (Brown 2001) depends upon the following claim:
Pediatric Hip Dislocation with Posterior Wall Acetabular Fracture: A Case Report

Traumatic hip dislocations with associated posterior wall fractures in children are injuries that can result in severe morbidity if not recognized and treated appropriately. Open reduction and internal fixation is recommended if the hip remains unstable after relocation or if there is significant incongruity of the articular surface of the hip after reduction. Hearty et al. recently published two cases of a posterior wall fracture in a skeletally immature patient showing how plain radiographs and CT scans were inadequate in determining the extent of the injury and that MRI was a much more reliable indication of what was seen at surgery [1]. In this case report, we describe an unusual case of a skeletally immature patient who sustained a traumatic hip dislocation with an associated posterior wall fracture. With similarity to the experience already reported [1], both CT and plain x-ray imaging failed to completely illustrate the joint injury. MRI provided better imaging of the true extent of the injury. Additionally, this patient, after having undergone a surgical procedure to remove intra-articular incarcerated fragments, was indicated for a second surgery based on an MRI done 2 weeks after the original surgery.
Determination of inelastic critical scattering at a first order phase transition in the CDW structure of 1TTaS2 using Mössbauer diffraction

Abstract We report Mossbauer diffraction measurements of the temperature dependence of the elastic and inelastic intensities at the (100) Bragg reflection in 1TTaS 2 . These measurements use a newly developed microfoil conversion electron (MICE) spectrometry. They cover the temperature range from 19°C to 100°C, bracketing the first order 1T 1 to 1T 2 phase transition in the charge density wave structure at 79°C. The elastic Bragg peak shows a discontinuity at the phase transition as reported by Moret and Colella. The inelastic scattering shows a significant peak near the phase transition. This peak is interpreted as inelastic critical scattering at this first order phase transition.
The role of nuclear fusion in pollen embryogenesis of Datura innoxia Mill.

If anthers of Datura innoxia containing microspores are cultured at 28° C for 24 h, two forms of haploid pollen grains are produced; one with typical unequal generative and vegetative nuclei (A), and the other with equal vegetativetype nuclei (B). The A form predominates. After 24 to 72 h in culture, three embryogenic events ensue; 1) division of the vegetative cell in A grains accompanied by rapid degeneration of the generative cell, 2) simultaneous or independent mitosis of the nuclei in B grains, and 3) simultaneous mitosis of both the generative and vegetative nuclei in A grains following two successive cycles of DNA synthesis in the generative nucleus, but only one in the vegetative nucleus (C). The endoreduplicated generative nucleus gives rise to diplochromosomes which it is postulated divide on a common spindle together with the vegetative chromosomes to yield a 3n proembryoid. In other C grains, simultaneous mitosis of an endoreduplicated generative nucleus and two vegetative daughter nuclei can occur. Nuclear fusion in these grains is envisaged as leading to a 4n proembryoid. Diploid proembryoids probably arise by nuclear fusion in A or B grains. At plantlet emergence, mainly n and 2n plantlets are obtained. Higher ploidy proembryoids fail to develop probably as a result of competitive influences.
Clinical experience reported as a retrospective study

We are very much aware of the problems with a retrospective analysis. However, we believe that our clinical experience with the two preparations in a highly successful IVF program is of value to readers. The January 1998 to April 1999 time frame was chosen because during that period, we were giving no recommendations to patients regarding selection of gonadotropins. In April 1999, we looked back at our findings and began to share these retrospective results with our patients.
Linear stability analysis for high-velocity boundary layers in liquid-metal magnetohydrodynamic flows

Abstract This paper presents a linear stability analysis for the fully developed liquid-metal now in a constant-area rectangular duct with thin metal walls and with a strong, uniform, transverse magnetic field. For the steady flow, there are large velocities inside the boundary layers adjacent to the sides which are parallel to the applied magnetic field. There are two independent eigenvalue problems for the linear stability of the high-velocity side layers. The first problem involves disturbance vorticity which is perpendicular to the magnetic field, and these disturbances decay for all wavelengths and Reynolds numbers. The second problem involves disturbance vorticity which is parallel to the magnetic field, and the critical Reynolds number for these disturbances is 313. The critical disturbance involves a short axial scale and a high velocity in the direction perpendicular to the side. Both of these characteristics have positive implications for the heat transfer through this boundary layer. This heat transfer is important in liquid-lithium cooling systems or “self-cooled blankets” for magnetic confinement fusion reactors. In such blankets, a high-velocity boundary layer occurs adjacent to the “first wall”, which faces the fusing plasma.
Drilling Multilayer Glass‐PTFE Circuit Boards

In this paper, reproduced by permission of the Institute of Printed Circuits (USA), the author discusses some of the problems encountered when drilling holes which must be plated through in multilayer glass cloth‐PTFE circuit boards and gives recommendations for overcoming them.
Histology and Molecular Aspects of Central Neurocytoma

Central neurocytoma (CN) is a well-differentiated tumor of neural cells occurring within the ventricles. It is composed of monomorphic cells with round, regular nuclei within clear cytoplasm and must be distinguished from other clear cell tumors. Immunohistochemical markers of CN that aid in diagnosis include synaptophysin and neuronal nuclear antigen. The molecular biology of these tumors is becoming increasingly elucidated, particularly with the use of microarray analyses. Several oncogenic pathways have been suggested by these studies. Although progress continues to be made, knowledge of CN has yet to dictate targeted therapies in treating patients with these tumors.
Asthma in the elderly: Diagnosis and management

The National Asthma Education and Prevention Program's "Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma" apply to all ages. This review discusses additional specific points for elderly patients. These patients are very heterogeneous. Their asthma can have begun at any time and can vary greatly in severity. It is frequently associated not only with any of the diseases that affect older persons but also with comorbid lung diseases. Many patients have irreversible airway obstruction, which is due to severe airway remodeling, chronic obstructive pulmonary disease, or bronchiectasis. Diagnosis should include chest radiography and computed tomographic scanning to diagnose other lung diseases if FEV 1 remains low after treatment. Asthma pathogenesis includes not only IgE-mediated allergy but also innate immune inflammation from endotoxin and trypsin-like proteases, and therefore evaluation and control of environmental exposures is an important part of management. Pharmacologic treatment, too, is adjusted to achieve and maintain control and is basically the same for all ages, except that elderly patients have reduced response to bronchodilators and increased side effects from beta adrenergic agonists and glucocorticoids. Many elderly patients have difficulty inhaling aerosols, and therefore nebulizers might be a better delivery system. Oral medications have the benefit of greater ease of administration and greater efficacy on the peripheral airways. Leukotriene antagonists and low-dose theophylline are often helpful additives to aerosol glucocorticoids. Oral glucocorticoids might be indicated for severe asthma.
Defining hierarchies of stemness in the intestine: evidence from biomarkers and regulatory pathways

For decades, the rapid proliferation and well-defined cellular lineages of the small intestinal epithelium have driven an interest in the biology of the intestinal stem cells (ISCs) and progenitors that produce the functional cells of the epithelium. Recent and significant advances in ISC biomarker discovery have established the small intestinal epithelium as a powerful model system for studying general paradigms in somatic stem cell biology and facilitated elegant genetic and functional studies of stemness in the intestine. However, this newfound wealth of ISC biomarkers raises important questions of marker specificity. Furthermore, the ISC field must now begin to reconcile biomarker status with functional stemness, a challenge that is made more complex by emerging evidence that cellular hierarchies in the intestinal epithelium are more plastic than previously imagined, with some progenitor populations capable of dedifferentiating and functioning as ISCs following damage. In this review, we discuss the state of the ISC field in terms of biomarkers, tissue dynamics, and cellular hierarchies, and how these processes might be informed by earlier studies into signaling networks in the small intestine.
Removal of Reaction Solvent by Extractive Workup: Survey of Water and Solvent Co-extraction in Various Systems

In some chemical processes, extractive workup is used to remove the solvent of reaction in an aqueous layer and to isolate the product in the organic layer. Most of the time some reaction solvent is co-extracted in the organic layer, along with some water. This has a non-negligible impact on subsequent operations (washing, crystallization), and we have thus determined those levels for ten reaction solvents and five extraction solvents in order to help the process chemist in the development of efficient isolation procedures.