cssi/SciSciGPT-SciSciNet huggingface dataset:
Sleep Disturbances, Obesity, and Cognitive Function in Childhood: A Mediation Analysis.

Background Childhood cognitive development is influenced by biological and environmental factors. One such factor, obesity, impairs cognitive development and is associated with sleep disturbances. Objectives We aimed to examine the mediating role of sleep disturbances on the relation between BMI and cognitive function in children. Methods A total of 9951 children aged 9-10 y were included in this cross-sectional study. Children were recruited from the longitudinal ABCD (Adolescent Brain Cognitive Development) Study. Cognitive development was assessed using metrics for fluid, crystallized, and total cognitive function. Mediation analyses were conducted via linear regression modeling, with adjustment for potential confounders (sex, age, ethnicity, household income, parental education, and self-reported physical activity) for each of the 3 outcomes. Mediation significance was determined by bootstrapping. Results A statistically significant inverse association was found between BMI and total (β = -0.41, P < 0.001) and fluid (β = -0.49, P < 0.001) cognition, but not for crystallized cognition. Total sleep disturbances partially mediated the association between BMI and fluid cognition (indirect effect: -0.02, P = 0.002; proportion of the total effect: 0.05, P = 0.002), but no mediation was found in the association between BMI and total cognition. Conclusions Sleep disturbances partially mediate the effect of childhood obesity on cognitive function, particularly in fluid cognitions. Future work is necessary to understand the effects of sleep disturbances and obesity on reduced childhood cognition throughout time, predominantly across the life course.
Flow and Scour around Idealized Porous Engineered Log Jam Structures

AbstractEngineered log jams (ELJs) are used widely in practice as a river restoration measure. One desired feature of an ELJ is its porous nature, which plays an important role in hydrodynamics and...
Improving Conceptual Print Knowledge: A Description of Intervention Considerations for Children With Hearing Loss

Purpose The purpose of this clinical focus article was to describe specific considerations for print-referencing interventions for children with hearing loss and present a case study. Method One pr...
Fetal Brain Elicits Sexually Conflicting Transcriptional Response to the Ablation of Uterine Forkhead Box A2 (Foxa2) in Mice

In this study, we investigated the effects of ablation of uterine Forkhead Box A2 (Foxa2) on gene expression of fetal brain relative to placenta. Using a conditional knockout mouse model for uterine Foxa2, here we show that the lack of uterine Foxa2 elicits a sexually-conflicting transcriptional response in the fetal brain relative to placenta. The ablation of Foxa2 in the uterus altered expression of genes related to growth, nutrient sensing, aging, longevity and angiogenesis among others. In the wildtype mice, these genes were expressed higher in the fetal brain and placenta of males compared to females. However, in mice lacking uterine Foxa2, the same genes showed the opposite pattern i.e., higher expression in the fetal brain and placenta of females compared to males. Based on the known marker genes of mice placenta and fetal brain cells, we further predicted that the genes exhibiting the sexually conflicting expression were associated with vascular endothelial cells. Overall, our study suggests that uterine Foxa2 plays a role in the regulation of the brain-placental axis by influencing the fetoplacental vascular changes during pregnancy.
Smoking enhances suicide risk-a significant role in the COVID-19 pandemic?

The COVID-19 outbreak has severely affected the whole world. Considerable evidence suggests that tobacco smoking is associated with increased severity of COVID-19 and death in COVID-19 patients. Tobacco smoking cessation is necessary to decrease COVID-19-related hospitalizations and deaths. In this commentary, I suggest that tobacco smoking cessation is also needed to reduce suicidal behavior during and after the COVID-19 pandemic. Significant evidence suggests that the COVID-19 pandemic leads to increased tobacco consumption as smokers use more tobacco to cope with pandemic related stress, anxiety, depression, and loneliness. Multiple studies have demonstrated that tobacco smoking is associated with suicidal ideation, suicide attempts, suicide death, and a contributing factor in the pathophysiology of suicide. Smoking may increase the probability of development of post-COVID syndrome because it increases severity of COVID-19. Suicide risk may be increased in individuals with post-COVID syndrome. Smoking prevention and cessation should be a target of suicide prevention interventions during and after the COVID-19 pandemic. The COVID-19 pandemic enhances the need to act to integrate tobacco smoking cessation in the health care as a standard of patient care.
Biologically Active Components and Properties of Bordetella perfussis

Publisher Summary This chapter discusses the biologically active components and properties of Bordetella pertussis. A variety of biological effects are observed in experimental animals following injection of phase I Bordetella pertussis cells or products. It includes sensitization to the lethal effects of the pharmacological agents histamine and serotonin as well as to nonspecific stresses such as cold and peptone shock; unresponsiveness to the induction of hyperglycemia by epinephrine, which has been attributed to the causation of a β-adrenergic blockade; leukocytosis with predominating lymphocytosis; adjuvanticity with respect to both antibody production—including reaginic antibody ( IgE )—and cell-mediated immunity; and direct, acute toxic effects which are in general related to either a distinct heat-labile toxin or to heat-stable lipopolysaccharide endotoxin. In addition, components of B. pertussis can be shown to induce striking effects in in vitro systems. Paradoxically, while clinical pertussis has become of decreasing importance where effective vaccines are routinely used; there has been an increased interest in the biological activities of B. pertussis.
Multicast data dissemination

Distributing large amounts of information on a computer network requires a data-dissemination server that is able to accommodate many interested clients making varied requests for data. For such a server, its outgoing network connection is a bottleneck that severely limits the number of clients and the size of shared data that the server can handle. To ameliorate this bottleneck, multicast allows a server to address a single transmission of data to multiple clients at once, reducing the repeated transmission of the same data items to different clients. Consequently, the server is able to provide faster transmissions to more clients than otherwise possible over the same network connection using unicast transmissions alone. To handle varied requests from many clients, the server must have an efficient way to decide which of the many requested items to send at any one time. This dissertation considers a variety of data schedulers to optimize this task for several performance metrics and a variety of client loads, including downloaders receiving sets of data as quickly as possible, and subscribers striving to keep changing data items current. Using modelling and simulation of such a multicast facility, we show the dramatic performance difference between various schedulers and the effects of batching clients over time. Because clients can have differing network capacities, the server must be able to deliver its data items reliably over client connections of varying loss rates. This dissertation shows how to exploit the unique properties of this system to extend traditional reliability techniques and reduce average client wait time by over 30%. Also, the server must decide how to slice its available outgoing network capacity into data channels, how to assign its data items to those channels, and how to assign clients to the channels given clients' varied requests and download speeds. We reveal the choices that can improve performance three-fold or more over their alternatives: Surprisingly, finding the good choices does not require advance knowledge of clients' varied download speeds, once the server chooses the slowest speed to support. Finally, this dissertation details challenges, design, and evaluation for a prototype using IP multicast.
Poverty, Inequality, and City Homicide Rates: Some Not So Unexpected Findings

Messner's recent investigation of homicide and relative and absolute economic deprivation is replicated here, but cities rather than SMSA's and three years (1950, 1960, 1970) rather than one (1970) are considered. Because of tremendous intra-unit variation for SMSAs with respect to homicides and sociodemographic characteristics (an important variation that is masked when data are aggregated on a SMSA level), cities are a preferable unit of analysis in cross-sectional investigations of homicide. Where M e s m found a significant negative relationship between percentage of poverty (absolute deprivation) and homicides, I consistently find the opposite pattern as predicted. In both studies, however, there is only a slight and nonsignificant relationship between relative economic deprivation (income inequality) and homicides. Unlike Messner, however, I do not consider this finding surprising. At best, there is only a weak theoretical linkage between homicide and relative economic deprivation. Accordingly, the results of this investigation for both absolute and relative deprivation are neither “perplexing” nor do they warrant the “serious reconsideration of the linkages between poverty, inequality and the homicide rate” that Messner (1982: 112) calls for.
The Synchronous Orbit Magnetic Field Data Set

The magnetic field at synchronous orbit is the result of superposition of fields from many sources such as the earth, the magnetopause, the geomagnetic tail, the ring current and field-aligned currents. In addition, seasonal changes in the orientation of the earth's dipole axis causes significant changes in each of the external sources. Main reasons for which the synchronous orbit magnetic field data set is a potentially valuable resource are outlined. The primary reason why synchronous magnetic field data have not been used more extensively in magnetic field modeling is the presence of absolute errors in the measured fields. Nevertheless, there exists a reasonably large collection of synchronous orbit magnetic field data. Some of these data can be useful in quantitative modeling of the earth's magnetic field. A brief description is given of the spacecraft, the magnetometers, the standard graphical data displays, and the digital data files.
The effect of light rare earth element substitution in Yb14MnSb11 on thermoelectric properties

After the discovery of Yb14MnSb11 as an outstanding p-type thermoelectric material for high temperatures (≥900 K), site substitution of other elements has been proven to be an effective method to further optimize the thermoelectric properties. Yb14−xRExMnSb11 (RE = Pr and Sm, 0 < x < 0.55) compounds were prepared by powder metallurgy to study their thermoelectric properties. According to powder X-ray diffraction, these samples are iso-structural with Yb14MnSb11 and when more than 5% RE is used in the synthesis the presence of (Yb,RE)4Sb3 is apparent after synthesis. After consolidation and measurement, (Yb,RE)Sb and (Yb,RE)11Sb10 appear in the powder X-ray diffraction patterns. Electron microprobe analysis results show that consolidated pellets have small (Yb,RE)Sb domains and that the maximum amount of RE in Yb14−xRExMnSb11 is x = 0.55, however, (Yb,RE)11Sb10 cannot be distinguished by electron microprobe analysis. By replacing Yb2+ with RE3+, one extra electron is introduced into Yb14MnSb11 and the carrier concentration is adjusted. Thermoelectric performance from room temperature to 1275 K was evaluated through transport and thermal conductivity measurements. The measurement shows that Seebeck coefficients initially increase and then remain stable and that electrical resistivity increases with substitutions. Thermal conductivity is slightly reduced. Substitution of Pr and Sm leads to enhanced zT. Yb13.82Pr0.18Mn1.01Sb10.99 has the best maximum zT value of ∼1.2 at 1275 K, while Yb13.80Sm0.19Mn1.00Sb11.02 has its maximum zT of ∼1.0 at 1275 K, respectively, ∼45% and ∼30% higher than Yb14MnSb11 prepared in the same manner.
Influence of iron on in vivo proliferation and lethality of L1210 cells.

The ability of iron to stimulate the growth of L1210 cells both in DBA-2 mice and in cell culture is evaluated. Although in vitro stimulation is absent, in vivo studies clearly indicate higher numbers of tumor cells in the presence of supplemental iron. When mice were given iron i.p., at levels comparable to clinical doses for humans (24 mg/kg body weight), the tumor load recovered from their peritoneum was substantially greater than from controls without iron supplements. Furthermore, at higher levels of supplemental iron (250 mg Fe/kg body weight), the pretreated animals inoculated with L1210 cells died in 9.7 d whereas controls died in 12.2 d (i.e., 25% faster). As expected, the lower iron dose (24 mg/kg) also resulted in shorter life spans, although the effects were less striking. It is the belief of these authors that these data support the opinion that "anemia of chronic disease" associated with leukemia and possibly other malignancies may represent a host defense mechanism as has been postulated by others (1, 8).
The HeLa Pur factor binds single-stranded DNA at a specific element conserved in gene flanking regions and origins of DNA replication.

Abstract A major site of DNA bending is located 1.6 kb upstream of the P1 transcription start site of the human c-myc gene, near the center of a reported zone of initiation of DNA replication. A repeated, purine-rich element, termed PUR, at the bend site is specifically bound by a protein in HeLa cell nuclear extracts. This protein has specific affinity for the purine-rich single strand of the element. Methylation interference maps a pattern of specific contact points with guanosine bases in a 24-mer oligonucleotide containing the element. UV cross-linking reveals that contact is made by a polypeptide of approximately 28 kDa. The PUR element is present at origins of replication and in gene flanking regions in a variety of eukaryotes from yeasts through humans. The consensus sequence GGNNGAGGGAGARRRR has been derived. This element is present near centers of regions of two mammalian loci (human c-myc and hamster dhfr) recently reported as initiation zones for DNA replication. A 24-mer oligonucleotide representing the hamster dhfr version of the PUR element effectively competes with the human c-myc version for binding to Pur.
The Role of Grandmothers and Older Women in the Survival of Children with Kwashiorkor in Urban Accra, Ghana

In this article, we present findings from field studies conducted during 1999 and 2002 in Accra, Ghana on the role of Ghanaian grandmothers in the survival of childhood kwashiorkor. Qualitative family interviews were conducted to describe the identification, intervention, and development of malnourished ethnic Ga children. Childhood malnutrition in its various forms continues to be a major cause of mortality and challenges child development in emerging nations such as Ghana. This is generally, but not exclusively, true among the poor. Efforts that promote nutrition education, or dietary intervention, have often failed because intervention requires a more sophisticated understanding of malnutrition than a simplistic relationship to poverty or the lack of available food supplies. We present evidence that survival of protein-caloric malnutrition, kwashiorkor, is directly related to compliance in nutritional rehabilitation programs, and such compliance is associated with collective familial decision making th...
Preoperative Binocular Considerations

The development of normal binocular vision is a complex and delicate process that begins during the early critical period of vision development in infancy. Any insult to the immature visual system, such as improper alignment of the visual axes, or asymmetric retinal images, will result in specific sensory adaptations designed to provide the best possible binocularity in spite of the underlying result. One such adaptation is anomalous retinal correspondence (ARC), the detection of which is a critical step in the preoperative testing process. While the presence of ARC is not necessarily a contraindication to strabismus surgery, evaluation of retinal correspondence is necessary to determine the risk of postoperative paradoxical diplopia or the likelihood of repeat muscle surgery. ARC can be detected using equipment found in every ophthalmologist's office; however, a small but worthwhile investment in a pair of Bagolini glasses is recommended for easy and reliable testing.
Quantitative estimation of heteromorphism in C-bands of Cebus apella

A quantitative estimation of C-band polymorphism has been carried out in five chromosome pairs (nos 5, 11, 12, 13 and 19) in a male specimen of Cebus apella. This approach allowed us to estimate the heteromorphism index (HI) within each of the five chromosome pairs, and to clearly detect C-band heteromorphisms in two chromosome pairs (nos 12 and 13) in this species.
The metabolism of the isolated perfused canine liver.

Summary An isolated liver perfusion was used for metabolic interrelation studies in our laboratory. The liver slices, after a 2-hr perfusion period in various pretreated groups, were also studied for carbohydrate metabolism. It was found that aerobic and anaerobic metabolism of liver slices treated with deoxycorticosterone acetate, testosterone, and partial ligation of the thoracic inferior vena cava, were the same as in normal livers. We also observed depression of the glycolytic pathway for utilizing exogenous fructose in the group pretreated with carbon tetrachloride and common bile duct ligation. An increase in oxygen ocnsumption in common bile duct-pretreated animals was also observed. Such studies suggest that hepatic metabolic performance in vitro or after perfusion cannot, therefore, provide infallible information on the prior presence of important host drug treatments in hepatic disease states. Such features may complicate donor considerations in hepatic transplantation patients.
Test generation using the COBOL data base management system

This project in data base management and design has two purposes. The first, and most important purpose, is to learn the fundamentals of data base development from the standpoint of the Data Base Administrator and those of data base usage from the programmer's viewpoint by using the COBOL language and the COBOL Data Base Management System. The second purpose is to develop a system to be used by the Computer Science Department of The University of Mississippi for computer-aided instruction.
Synthesis and kinetic studies of a novel singlet oxygen donor with acceptor-binding capability

Abstract A singlet oxygen donor has been prepared in which an 18-crown-6 ether residue is attached to the 2,3-position of a 9,10-diphenylanthracene peroxide. Kinetic and preliminary donor-acceptor recognition studies are reported.
A novel, low-cost pneumatic positioning system

Applications requiring accurate position control are in increasing use in industry. Pneumatic servo systems can provide a clean, accurate, robust positioning system; however, the proportional valves used in such systems are relatively expensive. The use of solenoid valves to replace a proportional flow control valve can significantly lower the price of a positioning system. This substitution is possible if the solenoid valves are operated using a pulse-width-modulated (PWM) control scheme. This work presents a design in which position control is realized on a single-rod, double-acting cylinder. Two solenoid valves operate conventionally to fill either chamber of the cylinder, while a third valve uses pulse-width modulation in metering the exhaust flow.The experimental apparatus is capable of positioning a load along a horizontal axis to within ±0. 10 mm.
The crystal structure of the octamer [r(guauaca)dC]2 with six Watson-Crick base-pairs and two 3′ overhang residues

Abstract The crystal structure of an alternating RNA octamer, r(gu a ua c a)dC (RNA bases are in lower case while the only DNA base is in upper case), with two 3′ overhang residues one of them a terminal deoxycytosine and the other a ribose adenine, has been determined at 2.2 A resolution. The refined structure has an Rwork 18.6 % and Rfree 26.8 %. There are two independent duplexes (molecules I and II) in the asymmetric unit cell, a = 24.95, b = 45.25 and c = 73.67 A, with space group P212121. Instead of forming a blunt end duplex with two a+·c mispairs and six Watson-Crick base-pairs, the strands in the duplex slide towards the 3′ direction forming a two-base overhang (radC) and a six Watson-Crick base-paired duplex. The duplexes are bent (molecule I, 20°; molecule II, 25°) and stack head-to-head to form a right-handed superhelix. The overhang residues are looped out and the penultimate adenines of the two residues at the top end (A15) are anti and at the bottom (A7) end are syn. The syn adenine bases form minor groove A∗(G·C) base triples with C8-H···N2 hydrogen bonds. The anti adenine in molecule II also forms a triple and a different C2-H···N3 hydrogen bond, while the other anti adenine in molecule I does not, it stacks on the looped out overhang base dC. The 3′ terminal deoxycytosines form two stacked hemiprotonated trans d(C·C)+ base-pairs and the pseudo dyad related molecules form four consecutive deoxyribose and ribose zipper hydrogen bonds in the minor groove.
ESTIMATING THE NUMBER OF HOMELESS: Media Misrepresentation of an Urban Problen

In the 1980s several estimates were made of the size of the homeless population nationwide. An examination of these estimates shows that claims by advocacy groups that 2–3 million persons were home...
Distribution of Indel lengths.

Protein sequence alignment has become a widely used method in the study of newly sequenced proteins. Most sequence alignment methods use an affine gap penalty to assign scores to insertions and deletions. Although affine gap penalties represent the relative ease of extending a gap compared with initializing a gap, it is still an obvious oversimplification of the real processes that occur during sequence evolution. To improve the efficiency of sequence alignment methods and to obtain a better understanding of the process of sequence evolution, we wanted to find a more accurate model of insertions and deletions in homologous proteins. In this work, we extract the probability of a gap occurrence and the resulting gap length distribution in distantly related proteins (sequence identity < 25%) using alignments based on their common structures. We observe a distribution of gaps that can be fitted with a multiexponential with four distinct components. The results suggest new approaches to modeling insertions and deletions in sequence alignments.
ATA practice guidelines for the treatment of differentiated thyroid cancer: were they followed in the United States?

Abstract Background The aim of this study was to benchmark national practice patterns against American Thyroid Association guidelines for thyroidectomy, lymphadenectomy, and radioactive iodine (RAI) for differentiated thyroid cancer (DTC). Methods A cross-sectional analysis of patients with DTC in Surveillance, Epidemiology, and End Results was performed. Outcomes were practice accordance with guidelines for extent of surgery and RAI treatment. Predictors of accordance were identified. Results A total of 52,964 patients with DTC were included. Seventy-six percent were women, and 83% white. There was 71% accordance with surgery recommendations; among these, 15% underwent central lymphadenectomy, 31% had RAI but no lymphadenectomy, and 25% had RAI and lymphadenectomy. The highest accordance with guidelines was for patients aged 65 years and of black race had the lowest accordance ( P Conclusions Variation in practice suggests variation in the quality of care for DTC. Greater dissemination of evidence-based recommendations is needed for elderly and minority patients.
Noncontiguous locking techniques for parallel file systems

Many parallel scientific applications use high-level I/O APIs that offer atomic I/O capabilities. Atomic I/O in current parallel file systems is often slow when multiple processes simultaneously access interleaved, shared files. Current atomic I/O solutions are not optimized for handling noncontiguous access patterns because current locking systems have a fixed file system block-based granularity and do not leverage high-level access pattern information. In this paper we present a hybrid lock protocol that takes advantage of new list and datatype byte-range lock description techniques to enable high performance atomic I/O operations for these challenging access patterns. We implement our scalable distributed lock manager (DLM) in the PVFS parallel file system and show that these techniques improve locking throughput over a naive noncontiguous locking approach by several orders of magnitude in an array of lock-only tests. Additionally, in two scientific I/O benchmarks, we show the benefits of avoiding false sharing with our byte-range granular DLM when compared against a block-based lock system implementation.
Pyrazole and Pyrazolyl Complexes of cis-Bis(2,2'-bipyridine)-chlororuthenium(II) : Synthesis, Structural and Electronic Characterization, and Acid-Base Chemistry

Complexes of the type cis-[Ru(bpy)2(Cl)(L)]+ [bpy = 2,2′-bipyridine; with L = pyrazole (1H), 4-methylpyrazole (2H), and 3,5-dimethylpyrazole (3H)] were synthesized and isolated as hexafluorophosphate salts. The molecular structures of these new complexes were fully characterized by 1H NMR spectroscopy and ESI mass spectrometry, and the crystal structure of 3H·PF6 was determined by X-ray crystallography. Compound 3H·PF6 (C25H24ClF6N6PRu) crystallizes in the monoclinic space group P21/n with a = 12.102(2) A, b = 16.826(3) A, c = 13.016(2) A, β = 92.606(2)°, V = 2647.6(8) A3, and Z = 4. The crystal structure of 3H reveals the formation of an intramolecular hydrogen bond (2.562 A) between the pyrazole N(2)–H site and the chloride ligand. The redox and electronic absorption properties of 1H, 2H, and 3H, as well as their deprotonated counterparts [L = pyrazolate (1), 4-methylpyrazolate (2), and 3,5-dimethylpyrazolate (3)], were investigated by cyclic voltammetry and UV/Vis spectroscopy. For detailed analysis of the electronic nature of this series of pyrazolyl ligands, the results are discussed along with other relevant cis-[Ru(bpy)2(X)(Y)]n+ complexes. From spectrophotometric pH titrations, the basicity associated with the coordinated pyrazole/pyrazolate couple in water was found in all three cases to be unusually high, partly owing to the N–H···Cl hydrogen bond that stabilizes the protonated, azole state. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The Enterovirus 71 A-particle Forms a Gateway to Allow Genome Release: A CryoEM Study of Picornavirus Uncoating

Since its discovery in 1969, enterovirus 71 (EV71) has emerged as a serious worldwide health threat. This human pathogen of the picornavirus family causes hand, foot, and mouth disease, and also has the capacity to invade the central nervous system to cause severe disease and death. Upon binding to a host receptor on the cell surface, the virus begins a two-step uncoating process, first forming an expanded, altered “A-particle”, which is primed for genome release. In a second step after endocytosis, an unknown trigger leads to RNA expulsion, generating an intact, empty capsid. Cryo-electron microscopy reconstructions of these two capsid states provide insight into the mechanics of genome release. The EV71 A-particle capsid interacts with the genome near the icosahedral two-fold axis of symmetry, which opens to the external environment via a channel ∼10 A in diameter that is lined with patches of negatively charged residues. After the EV71 genome has been released, the two-fold channel shrinks, though the overall capsid dimensions are conserved. These structural characteristics identify the two-fold channel as the site where a gateway forms and regulates the process of genome release.
The psychological autopsy: solving the mysteries of death

The psychological autopsy is an important assessment tool used to identify aspects of a person's life that explain any lingering mystery that shrouds their death. In addition to answering questions of the past, the psychological autopsy has significant implications for the future. Statistics obtained from mortality data affect the course of health care research, the flow of resources, and ultimately public health policy. From a public health perspective, the misclassification of suicides as accidents or deaths from natural causes can negatively affect research funding and policy development related to suicide prevention efforts, making a standardized and accurate procedure imperative. Although the psychological autopsy was developed initially as a tool to assist the coroner in clarifying the cause of death, this procedure has transcended the confines of forensic science and has applications in the many arenas of litigation and public health policy. Language: en
Why are nitride lasers limited to the spectral range from ∼340 to 530 nm?

We recently suggested that careful optimization of residual strain in nitride laser structures could be used to extend the operating wavelength into the red and infrared spectral region (Sharma and Towe, J. Appl. Phys. 106, 104509 (2009) and Appl. Phys. Lett. 96, 191105 (2010) [1, 2]). At the other wavelength extreme, in the ultraviolet, non-optimal residual strain in nitride emitters with AlGaN layers and large crystal-field splitting energies can cause a switching in emitted light polarization characteristics, leading to less efficient devices. Although Al-rich AlGaN quantum wells favour shorter emission wavelengths, these structures also exhibit poor carrier confinement. These factors suggest that even in the ultra-violet, the key limiting constraint for the development of lasers is the amount of residual strain in the structures. To properly resolve these issues, a critical analysis of strain, quantum confinement, and the polarization properties of nitride quantum well structures is warranted (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Wave Function of Ionized Lithium

A nonrelativistic wave function for the $1s2{s}^{3}S$ state of singly ionized lithium has been found by using an expansion of the function in Legendre polynomials of the cosine of the angle between the lines joining the electrons to the nucleus. Previous work had indicated that the distance dependent coefficient of the angle-independent term of the expansion predominates over the others. This made it possible to obtain an accurate function by computing to high precision an approximate value of the coefficient as a function of the distances of the electrons from the nucleus. The calculation of this function of the two distances was facilitated by the separability of the wave equation satisfied by the function. An additive correction to this function and also the distance dependent coefficients of higher order Legendre polynomials, all of which were comparatively small, could then be calculated by relaxation and numerical variational methods of less accuracy. Application of tests based on the virial theorem and Green's theorem to the wave function were used as criteria of accuracy. The Ritz integral led to the energy value $\ensuremath{-}1.135724 \mathrm{Rhc}{Z}^{2}$, where $R$ is Rydberg's constant for lithium, $Z$ is the atomic number, and $h$ and $c$ are Planck's constant and the velocity of light, respectively. This result compares favorably with the experimental value, corrected for the relativistic effect and nuclear motion, of $\ensuremath{-}1.135722\ifmmode\pm\else\textpm\fi{}0.000025 \mathrm{Rhc}{Z}^{2}$. The hyperfine structure integral $1+\ensuremath{\epsilon}$ of Breit and Doermann was found to have the value 1.06191\ifmmode\pm\else\textpm\fi{}0.00003.
The Relationship Between Soil Water Potential, Environmental Factors, and Plant Moisture Status for Poblano Pepper Grown Using Tensiometer-Scheduled Irrigation

Managing irrigation using soil moisture sensors for automation can allow for a reduction in water use while avoiding drought stress and maintaining optimum yields in high-value crops. Measurements of plant water status such as leaf water potential and relative water content are often utilized to demonstrate the presence or lack of drought stress in plants subjected to varying soil moisture regimes. Poblano peppers (Capsicum annuum L.) were grown under four automated, tensiometer-controlled irrigation regimes with set points of on/off −30/−25, −40/−35, −50/−45, and −60/−55 kPa and a manually operated treatment with set points of −50/−10 kPa. Soil moisture data were collected at depths of 15 and 25 cm and plant midday leaf water potential and relative water content data were collected throughout the growing season. Yield and fruit quality were unaffected by irrigation treatment. Soil water potential was poorly correlated with plant leaf water potential and relative water content. Plant leaf water potential ...
Evidence for biogenic amine receptors in toad sciatic nerves

Summary Serotonin, l -epinephrine, histamine and other neurotropic drugs increase spike amplitude in toad sciatics. The biogenic amines, pentolinium, nicotine and arecoline antagonized nerve block induced by cocaine, procaine, chlorpromazine, imipramine, strychnine, LSD, etc. Reversal of conduction block (without removal of blocker) showed that the antagonism did not result from interference with penetration. The action of the biogenic amines seems related to interactions with specific receptors rather than to general ionic effects since (a) they antagonized both Na-dependent threshold raisers (cocaine) and Na-independent blockers (chlorpromazine); (b) specific competitive-like antagonisms were observed (serotonin vs. imipramine block; antihistaminics vs. histamine protection against cocaine). The presence of scattered synaptic-like receptors on the axonal membrane is discussed.
Amino acid sequence of the Peptostreptococcus elsdenii flavodoxin.

Abstract The amino acid sequence of the Peptostreptococcus elsdenii flavodoxin has been determined except for a few residues. The protein contains 137 amino acid residues and the NH2- and COOH-terminal residues are methionine and alanine respectively. The protein contains two cysteine residues in positions 54 and 127. However, the cysteine residue in position 127 appears to be involved in binding FMN and therefore the active site is located near the COOH-terminal position of the protein. There are no aromatic amino acid residues in this region of the protein.
Timber harvesting: effects on degradation of cellulose and lignin

Abstract Degradation rates of cellulose and lignin in forest organic soil after four harvesting treatments were measured radiometrically. Samples were taken monthly for 1 year. Three treatments included clearcutting, after which the residue was left ( rl ), removed ( rr ) or burned at 300–500°C ( rb ). An unharvested stand provided a control ( c ). Cellulose degradation peaked in spring (March through May) and fall (September through November) in all treatments. Cellulose degradation rates generally were lower than the control in the rb and rr treatments, but higher than the control in the rl treatment. Cellulose degradation over all treatments was positively correlated with microbial biomass (r = 0.68). Lignin degradation increased significantly during the summer (June through August) in all treatments.
NHE3 Regulatory Factor 1 (NHERF1) Modulates Intestinal Sodium-dependent Phosphate Transporter (NaPi-2b) Expression in Apical Microvilli

Pi uptake in the small intestine occurs predominantly through the NaPi-2b (SLC34a2) co-transporter. NaPi-2b is regulated by changes in dietary Pi but the mechanisms underlying this regulation are largely undetermined. Sequence analyses show NaPi-2b has a PDZ binding motif at its C terminus. Immunofluorescence imaging shows NaPi-2b and two PDZ domain containing proteins, NHERF1 and PDZK1, are expressed in the apical microvillar domain of rat small intestine enterocytes. Co-immunoprecipitation studies in rat enterocytes show that NHERF1 associates with NaPi-2b but not PDZK1. In HEK co-expression studies, GFP-NaPi-2b co-precipitates with FLAG-NHERF1. This interaction is markedly diminished when the C-terminal four amino acids are truncated from NaPi-2b. FLIM-FRET analyses using tagged proteins in CACO-2BBE cells show a distinct phasor shift between NaPi-2b and NHERF1 but not between NaPi-2b and the PDZK1 pair. This shift demonstrates that NaPi-2b and NHERF1 reside within 10 nm of each other. NHERF1−/− mice, but not PDZK1−/− mice, had a diminished adaptation of NaPi-2b expression in response to a low Pi diet. Together these studies demonstrate that NHERF1 associates with NaPi-2b in enterocytes and regulates NaPi-2b adaptation.
fgf8 mRNA decay establishes a gradient that couples axial elongation to patterning in the vertebrate embryo

Formation and patterning of the vertebrate embryo occur in a head-to-tail sequence. This progressive mode of body formation from the posterior end of the embryo requires a strict temporal coordination of tissue differentiation--a process involving fibroblast growth factor (FGF) signalling. Here we show that transcription of fgf8 messenger RNA is restricted to the growing posterior tip of the embryo. fgf8 mRNA is progressively degraded in the newly formed tissues, resulting in the formation of an mRNA gradient in the posterior part of the embryo. This fgf8 mRNA gradient is translated into a gradient of FGF8 protein, which correlates with graded phosphorylation of the kinase Akt, a downstream effector of FGF signalling. Such a mechanism provides an efficient means to monitor the timing of FGF signalling, coupling the differentiation of embryonic tissues to the posterior elongation of the embryo. In addition, this mechanism provides a novel model for morphogen gradient formation.
Atmosphere-magnetosphere-ionosphere system mami

The effects on the terrestrial atmosphere and ionosphere of energy and momentum sources of magnetospheric origin are investigated theoretically. Parameters measured by instruments on board the GGS spacecraft and by the GGS ground-based networks are used as inputs to the models that quantify the magnetosphere-ionosphere-thermosphere coupling. Images of the aurora acquired at ultraviolet, visible and X-ray wavelengths by instruments on board the POLAR spacecraft are particularly useful in this investigation by yielding good spatial coverage and high time resolution of the aurora.
The information-processing difficulty of incremental parsing

When an incremental parser gets the next word, its expectations about upcoming grammatical structures can change. When a word greatly constrains these grammatical expectations, uncertainty is reduced. This elimination of possibilities constitutes information processing work. Formalizing this notion of information processing work yields a complexity metric that predicts human repetition accuracy scores across a systematic class of linguistic phenomena, the Accessibility Hierarchy of relativizable grammatical relations.
Majority Rule with Lotteries on Alternatives

Lotteries as alternatives for social choices, 696. — Intransitivity difficulties, 697. — Sufficient conditions to avoid such difficulties, 699.
Experimental squamous cell lung tumors in Sprague-Dawley and murine pneumonitis-free rats.

Squamous cell bronchogenic carcinoma was produced in 34% of a group of specific pathogen-free rats in a mean time of 139 days by the use of point-source irradiation. In a group of Sprague-Dawley rats, identical tumors developed in 54% of animals after an average exposure time of 147 days. This study was undertaken to clarify whether the bronchogenic squamous cell carcinomas produced by this method are due to the effects of the point source of irradiation alone or to the additive effects of irradiation and chronic murine pneumonitis. The results of this study in specific pathogen-free rats indicate that murine pneumonitis is not a prerequisite for the development of neoplasia by this method. The electron microscopic findings presented support the histologic diagnosis of a well-differentiated squamous cell bronchogenic carcinoma, similar in appearance to the tumor found in humans. Cancer 44:598-603, 1979.
Reduced pollinator service and elevated pollen limitation at the geographic range limit of an annual plant

Mutualisms are well known to influence individual fitness and the population dynamics of partner species, but little is known about whether they influence species distributions and the location of geographic range limits. Here, we examine the contribution of plant-pollinator interactions to the geographic range limit of the California endemic plant Clarkia xantiana ssp. xantiana. We show that pollinator availability declined from the center to the margin of the geographic range consistently across four years of study. This decline in pollinator availability was caused to a greater extent by variation in the abundance of generalist rather than specialist bee pollinators. Climate data suggest that patterns of precipitation in the current and previous year drove variation in bee abundance because of its effects on cues for bee emergence in the current year and the abundance of floral resources in the previous year. Experimental floral manipulations showed that marginal populations had greater outcross pollen limitation of reproduction, in parallel with the decline in pollinator abundance. Although plants are self-compatible, we found no evidence that autonomous selfing contributes to reproduction, and thus no evidence that it alleviates outcross pollen limitation in marginal populations. Furthermore, we found no association between the distance to the range edge and selfing rate, as estimated from sequence and microsatellite variation, indicating that the mating system has not evolved in response to the pollination environment at the range periphery. Overall, our results suggest that dependence on pollinators for reproduction may be an important constraint limiting range expansion in this system.
Long-term seizure outcome in patients initially seizure-free after resective epilepsy surgery

Objective: To evaluate the likelihood of and risk factors for seizure recurrence in patients initially seizure-free after resective surgery for intractable epilepsy. Methods: One hundred seventy-five patients who underwent lobectomy between 1972 and 1992 and were seizure-free during the first postoperative year were retrospectively studied. Outcome was measured by relapse risk, presence of auras in otherwise seizure-free patients, and seizure frequency among relapsers. Factors significant in bivariate or Kaplan–Meier analysis or considered potentially predictive a priori were included in multivariate models. Results: Of the 175 patients (mean follow-up 8.4 years), 63% never relapsed. The likelihood of being seizure-free was 83 ± 6% 3 years after surgery, 72 ± 7% after 5 years, and 56 ± 9% after 10 years. After adjusting for age at surgery, duration of preoperative epilepsy, and resection site, normal pathology was associated with increased risk of relapse compared to mesial temporal sclerosis or other pathology ( p = 0.036; hazard ratio [HR] 2.38; 95% CI 1.06 to 5.34). Among patients otherwise seizure-free, preoperative illness of ≥20 years was associated with increased risk of postoperative auras ( p = 0.040; HR 3.55; 95% CI 1.06 to 11.90). Among relapsers, 51% experienced one or fewer seizures per year. Normal pathology and earlier relapse were associated with higher postoperative seizure frequency. Conclusions: In patients seizure-free during the first year after resective epilepsy surgery, the likelihood of remaining seizure-free declined to 56% over 10 years, but half of patients who relapsed had at most one seizure per year. Longer preoperative illness and normal pathology predicted poorer outcome.
Identification of two gene clusters involved in cyclohexanone oxidation in Brevibacterium epidermidis strain HCU.

Brevibacterium epidermidis HCU can grow on cyclic ketones and alcohols as a sole carbon source. We have previously reported the identification of two cyclohexanone-induced Bayer-Villiger monooxygenase genes by mRNA differential display. Using the related technique of Out-PCR, we have amplified large DNA fragments flanking the two monooxygenase genes. Two large gene clusters were sequenced. Several ORFs in each gene cluster encoded proteins homologous to cyclohexanol and cyclohexanone oxidation enzymes from Acinetobacter. However, the structure of these two gene clusters differs significantly from that of Acinetobacter, where the complete pathway has been described. To assess activity of these genes, they were cloned and expressed in Escherichia coli. In vivo and in vitro assays enabled us to assign functions to the expressed ORFs. These ORFs included a cyclohexanol dehydrogenase, two different e-caprolactone hydrolases and two 6-hydroxyhexanoate dehydrogenases belonging to different enzyme families. Because this environmental isolate is difficult to manipulate, we cannot determine at this time which cluster is involved in the degradation of cyclohexanone under physiological conditions. However, the original differential display experiments and some of the experiments reported here suggest the involvement of both gene clusters in the oxidation of cyclic ketones.
Analyzing the roles of mast cells and basophils in host defense and other biological responses

The sudden and systemic activation of mediator release from mast cells and basophils that can occur when some sensitized subjects are challenged by minute amounts of specific antigen (eg, from an insect sting or peanuts) can result in fatal ana-phylaxis, a reaction that arguably represents the most grotesque imbalance between the cost and benefit of an immune response. Why then do mast cells and basophils continue to exist and, in the case of mast cells, populate almost all vascularized tissues? This review will consider the roles of mast cells and basophils in health and disease, emphasizing particularly their proven or potential functions in host defense. We will also describe briefly some approaches to investigate mast cell and basophil functions in vivo, including the use of mast cells generated directly from embryonic stem cells in vitro.
Pollution detection by digital correlation of multispectral, stereo-image pairs

Abstract Remote detection of air pollution circulation patterns is proposed to eventually provide inputs for the prediction of hazardous surface concentrations in time for preventive emission control operations. Earth observations from space platforms will contain information on the height, mean velocity and lateral mixing scales of inversion layers and pollution plumes. Although this information is often not visible on photographs, it could conceivably be retrieved through a digital cross-correlation of multispectral stereo image pairs. Laboratory and field test results are used to illustrate the detection of non-visual inversion layers, the reduction of dominant signal interference, and the spectroscopic identification of combustion products.