cssi/SciSciGPT-SciSciNet huggingface dataset:
Adaptive Wireless Communications: Space-time coding

As is true for single-input single-output (SISO) communication links, there are many approaches for coding multiple-input multiple-output (MIMO) systems in an attempt to approach the channel capacity. Many of the space-time coding approaches have analogs in the SISO regime. The multiple antennas of MIMO systems enable spatial diversity, increased data rates, and interference suppression. In general, there are trades in these characteristics, depending upon the coding and receiver approach. One of the most important trade-offs in this regard is the trade-off between data rate and diversity whereby the data communication rate is reduced to improve probability of error or outage. That is to say, a fraction of the data rate is sacrificed to improve robustness. There have been numerous contributions in the field of space-time coding. The major contributions include References [8, 99, 307, 305, 306, 361, 362, 314, 57, 58, 292, 86, 207, 166, 119, 87, 222, 270, 42, 43, 269, 226, 196]. Of particular note are Reference [8] which introduced what is now known as the Alamouti code, a simple and elegant space-time code for systems with two transmitter antennas, Reference [307] which introduced systematic methods to evaluate space-time codes, and Reference [361] which analyzed the fundamental trade-offs between diversity and rate in multiantenna systems.
Map-Based Access to Multiple Educational On-Line Resources from Mobile Wireless Devices

While large volumes of relevant educational resources are available currently online, almost all existing resources have been designed for relatively large screens and relatively high bandwidth. Searching for the proper interface to access multiple resources from a mobile computer we have selected an approach based on self-organized hypertext maps. This paper presents our approach and its implementation in the KnowledgeSea system. It also discusses the ongoing work on using our approach with very narrow screens of Palmlike devices.
Reachability of uncertain linear systems using zonotopes

We present a method for the computation of reachable sets of uncertain linear systems. The main innovation of the method consists in the use of zonotopes for reachable set representation. Zonotopes are special polytopes with several interesting properties : they can be encoded efficiently, they are closed under linear transformations and Minkowski sum. The resulting method has been used to treat several examples and has shown great performances for high dimensional systems. An extension of the method for the verification of piecewise linear hybrid systems is proposed.
Application of the multigrid solution solution technique to hypersonic entry vehicles

Multigrid techniques have been incorporated into an existing hypersonic flow analysis code, the Langley aerothermodynamic upwind relaxation algorithm. The multigrid scheme is based on the full approximation storage approach and uses full multigrid to obtain a well-defined fine-mesh starting solution. Predictions were obtained using standard transfer operators, and a V cycle was used to control grid sequencing. Computed hypersonic flow solutions, compared with experimental data for a 15-deg blunted sphere-cone and a blended-wing body, are presented. It is shown that the algorithm predicts heating rates accurately, and computes solutions in one-third the computational time of the nonmultigrid algorithm.
Soy protein polymers: Enhancing the water stability property

ABSTRACT Soy protein based plastics have been processed in the past by researchers for various short-term applications; however a common issue is the high water sensitivity of these plastics. This work concentrates on resolving this water sensitivity issue of soy protein polymers by employing chemical and mechanical interaction at the molecular level during extrusion. The primary chemical interactions employed were anhydride chemistries such as maleic anhydride (MA), phthalic anhydride (PTA), and butylated hydroxyanisole (BHA). These were respectively used in conjunction with glycerol as a plasticizer to produce relatively water stable soy protein based plastics. Formulations with varying additive levels of the chemistries were extruded and injection molded to form the samples for characterization. The additive levels of anhydrides were varied between 3-10% tw/tw (total mass). Results indicated that phthalic anhydride formulations resulted in highest water stability. Plastic formulations with concentration up to 10% phthalic anhydride were observed to have water absorption as low as 21.5% after 24 hrs of exposure to water with respect to 250% for the control formulation. Fourier transform infrared spectroscopy (FTIR) was utilized to characterize and confirm the fundamental mechanisms of water stability achieved by phthalic and maleic anhydride chemistries. In addition, the anhydride formulations were modified by inclusion of cotton fibers and pretreated cotton powder in order to improve mechanical properties. The incorporation of cotton fibers improved the dry strength by 18%, but did not significantly improve
Life and death on the coral reef: an ecological perspective on scholarly publishing in the health sciences.

Objective: Reflecting patterns evident in past Janet Doe lectures, the 2004 address draws on the foundations of biology to provide a model that offers insights into the advent of electronic publications and choices for the future. Setting: The lecture sketches a picture of the fragile relationships found in complex ecosystems and illustrates how such interdependencies function in the environment of the coral reef. Analysis: Deriving lessons from the marine world, the lecture then shifts to a description of similarities in the realm of scholarly publishing, the impact of digital innovations in the marketplace, and the controversies and choices inherent in open access publications. Conclusions: Lessons from ecology and publishing lead to the conclusion that librarians must take action and risks in this time of dramatic environmental change.
Fire and Pesticides, A Review and Analysis of Recent Work

There are a number of circumstances that involve the burning of toxic materials, including pesticides, herbicides, insecticides, and poisonous plant or plant products. Toxicity issues of smoke from the Anacardiaceae family and the Oleander are discussed and contrasted with that from pesticides, herbicides, insecticides, and other organic materials. Work in two major European programs is reviewed. Survival fractions in smoke of 1 to 10% can be expected for some toxic compounds in fires. Survival fractions are dependent not only upon the specific toxic compound but on the fire scenario and other fuels present. Of importance, flaming combustion mat not ensure destruction of such compounds in real fire incidents.
Facets of mindfulness related to a change in anxiety following a mindfulness-based intervention

ABSTRACTMindfulness has been operationalized into five facets that can be measured: Observe, Describe, Act with Awareness, Nonjudgment, and Nonreactivity. The purpose of this literature review is to determine if any single facet of mindfulness is more robustly associated with a change in anxiety. Five studies measuring changes in mindfulness facets following a mindfulness-based intervention and their effects on anxiety symptoms were examined. The results of this review are inconclusive. No clear connection emerged based on the literature reviewed, though the facet of Nonjudgment may have a stronger relationship with a change in anxiety based on these studies.
Personality and risk for Alzheimer's disease in adults 72 years of age and older: a 6-year follow-up

We conducted secondary analyses to determine the relationship between longstanding personality traits and risk for Alzheimer’s disease (AD) among 767 participants 72 years of age or older who were followed for more than 6 years. Personality was assessed with the NEO-FFI. We hypothesized that elevated Neuroticism, lower Openness, and lower Conscientiousness would be independently associated with risk of AD. Hypotheses were supported. The finding that AD risk is associated with elevated Neuroticism and lower Conscientiousness can be added to the accumulating literature documenting the pathogenic effects of these two traits. The link between lower Openness and AD risk is consistent with recent findings on cognitive activity and AD risk. Findings have implications for prevention research and for the conceptualization of the etiology of Alzheimer’s Disease.
Preparation and structural characterization of [Co4(h5-C5H5)4(CO)4(μ4-As)]+BF4- ·C6H6: An organometallic complex containing a tetrahedral-like arsenic atom coordinated to four metal atoms

Abstract The room-temperature reaction of cyclopentadienylcobalt dicarbonyl in benzene solution with arsenic trifluoride has unexpectedly produced in low yield a new tetranuclear metal complex [Co 4 ( h 5 -C 5 H 5 ) 4 (CO) 4 (μ 4 -As)] + BF 4 - · 1 2 C 6 H 6 by the extraction of boron from the Pyrex-glass flask as the tetrafluoroborate anion. This compound has been characterized by physical means including a single-crystal X-ray analysis which not only unambiguously established the actual composition but also revealed an example of an unusual organometallic complex containing a quadruply bridging arsenic atom linking four metal atoms. The entire [Co 4 ( h 5 -C 5 H 5 ) 4 (CO) 4 (μ 4 -As)] + monocation ideally posesses an S 4 · 4 configuration which consists of two essentially identical [Co 2 ( h 5 -C 5 H 5 ) 2 (CO) 2 ] fragments joined to each other by a metal-coordinated tetrahedral-like arsenic atom. The central Co 4 As core of the diamagnetic monocation, which is structurally related and electronically equivalent to the previously reported [Fe 2 (CO) 8 ] 2 (μ 4 -Sn) molecule, has an approximate D 2d · 42 m geometry with two electron-pair Co—Co bonding distances of 2.60 A (av) and four Co—Co nonbonding distances of 4.14 A (av) and with a mean CO—As bond length of 2.27 A. The isolated compoundcrystalizes with two cations, two anions, and one benzene molecule of solvation in a reduced triclinic unit cell of P 1 symmetry and of dimensions a = 9.230(b), b = 18.815(10), c = 8.939(4) A, α = 100.38(5), β = 95.49(4), and γ = 76.21(5)°. The structure was refined by full-matrix least-squares techniques to an unweighted R 1 value of 4.8% for 1784 independent diffracometry-collected data with I ⩾ 2σ( I ).
Have Historical Sociologists Forsaken Theory? Thoughts on the History/Theory Relationship

With the re-emergence of historical sociology as a dominant focus of inquiry has come a renewed interest in more general methodological, theoretical, and epistemological issues that have long occup...
Micromechanics of macroelectronics

Abstract The advent of flat-panel displays has opened the era of macroelectronics. Enthusiasm is gathering to develop macroelectronics as a platform for many technologies, ranging from paper-like displays to thin-film solar cells, technologies that aim to address the essential societal needs for easily accessible information, renewable energy, and sustainable environment. The widespread use of these large structures will depend on their ruggedness, portability and low cost, attributes that will come from new material choices and new manufacturing processes. For example, thin-film devices on thin polymer substrates lend themselves to roll-to-roll fabrication, and impart flexibility to the products. These large structures will have diverse architectures, hybrid materials, and small features; their mechanical behavior during manufacturing and use poses significant challenges to the creation of the new technologies. This paper describes ongoing work in the emerging field of research –the mechanics of macroelectronics, with emphasis on the mechanical behavior at the scale of individual features, and over a long time.
Luxation of the Elbow Complicated by Proximal Radio-Ulnar Translocation

Luxation of the elbow complicated by proximal radio-ulnar translocation is a rare entity. The clue to diagosis is the reversed position of the bones of the proximal forearm. In the a.p. projection the radial head articulates with the trochlea and the ulna with the capitellum. This unexpected anatomic relationship is easily overlooked. Delayed reduction may result in permanent impairment of elbow motility. Our experience with three recent cases is presented.
Information technology acceptance in the internal audit profession: Impact of technology features and complexity

Abstract Although various information technologies have been studied using the technology acceptance model (TAM), the study of acceptance of specific technology features for professional groups employing information technologies such as internal auditors (IA) has been limited. To address this gap, we extended the TAM for technology acceptance among IA professionals and tested the model using a sample of internal auditors provided by the Institute of Internal Auditors (IIA). System usage, perceived usefulness, and perceived ease of use were tested with technology features and complexity. Through the comparison of TAM variables, we found that technology features were accepted by internal auditors in different ways. The basic features such as database queries, ratio analysis, and audit sampling were more accepted by internal auditors while the advanced features such as digital analysis, regression/ANOVA, and classification are less accepted by internal auditors. As feature complexity increases, perceived ease of use decreased so that system usage decreased. Through the path analysis between TAM variables, the results indicated that path magnitudes were significantly changed by technology features and complexity. Perceived usefulness had more influence on feature acceptance when basic features were used, and perceived ease of use had more impact on feature acceptance when advanced features were used.
Toward a General Linguistic and Nonlinguistic Sociocultural Typology and Its Dynamics

Language is a system of systems that fit into the total sociocultural macrosystem. All these systems react intra- and intersystemically according to general principles mapped out by the authors in their book Parametric Linguistics. Analysis of some of these principles in this article raises the question of scientific prediction within the sociocultural macrosystem.
Fluorescent vs. radioactive microsphere measurement of regional myocardial blood flow

Objectives: This study compared simultaneous regional myocardial blood flow (RMBF) measurements using fluorescent microspheres (FM) and radiolabeled microspheres (RM). The utility of an internal standard during processing was also examined. Methods: Paired FM and RM were injected into the left atrium of 9 anaesthetised rabbits. RMBF was altered by use of either regional ischaemia or (−)- N 6-(2-phenylisopropyl)-adenosine. Radioactivity of blood reference and tissue samples was quantitated using standard methods. Samples were then digested with potassium hydroxide and microspheres recovered by vacuum filtration, with an additional label of FM as the internal standard. FM labels were extracted using Carbitol® acetate and quantitated using fluorescence spectroscopy. Agreement between the fluorescent and radioactive methods was assessed using both orthogonal regression and difference-against-mean analyses. Results: Using recovery- un corrected data, the slope of the orthogonal regression of RM and FM-determined RMBF was not statistically different from 1, but the intercept was statistically different from 0 [−0.03(0.01), P = 0.005] and the mean RMBF by each method differed from one another [1.24(0.08) vs. 1.17(0.08) ml · min−1 · g−1, P = 0.0002]. The mean ±2 s.d. of the differences of RMBF (RM minus FM) was +0.07 ± 0.30 ml · min−1 · g−1. Although recovery of FM from tissue averaged 97.6(1.2)%, use of the internal standard to correct for losses substantially improved the agreement between RM and FM-determined RMBF: the orthogonal regression slope was not statistically different from 1, the intercept was not statistically different from 0, and the means of the flows were not different. The mean ±2 s.d. of the differences of RMBF was −0.01 ± 0.22 ml · min−1 · g−1. The internal standard also improved RMBF estimates from samples with simulated large spillage during processing. Conclusion: Fluorescent microspheres are an equivalent alternative to radiolabeled microspheres for the estimation of RMBF. Although the overall recovery of microspheres using this technique was high, use of an internal standard is recommended for correction of random losses.
Dynamic mechanical analyses of Nafion®/organically modified silicate nanocomposites

Nafion®/organically modified silicate (ORMOSIL) hybrids were generated via polymer in situ sol-gel copolymerizations of tetraethylorthosilicate (TEOS) with difunctional and trifunctional organoalkoxysilane monomers, and the dynamic mechanical relaxations and thermomechanical stability of the resultant composites were investigated. All ORMOSIL fillers restrict main-chain and side-chain mobility. The results suggest that sulfonic acid side chains become entrapped in silicate or ORMOSIL structures that evolve during the in situ sol-gel process. Some but not all of the ORMOSIL combinations display trends in the a or β relaxation temperature with respect to the TEOS comonomer ratio. All of the hybrids have greater high-temperature thermomechanical stability than the unfilled acid form. There are definite composition trends in the vertical displacement of the storage-modulus-temperature curves. For some of the semiorganic comonomers, there is a monotonic increase in storage modulus with decreasing comonomer content in the high-temperature regime, which is understood in terms of a progressive immobilization of the long side chains by progressively more rigid ORMOSIL nanostructures. For other semiorganic comonomers, the high-temperature plateau shifts upward to a maximum and then shifts downward with decreasing comonomer fraction. In addition to the chemical nature of the imparted nanophases, these molecular motions are expected to influence the transport properties of these novel heterogeneous membranes.
Does the addition of glutamine to enteral feeds affect patient mortality

Objective: Studies have failed to consistently demonstrate improved survival in intensive care unit (ICU) patients receiving immune-modulating nutrient-enhanced enteral feeds when compared with standard enteral feeds. The objective was to study in a prospective fashion the effects of adding glutamine to standard or immune-modulated (supplemented with omega-3 fatty acids, -carotene, and amino acids such as glutamine and arginine) tube feeds. Design: Prospective, unblinded study using sequential allocation. Setting: A university surgical trauma ICU. Patients: All surgical and trauma patients admitted to the surgical trauma ICU at a university hospital over a 3-yr period who were to receive enteral feeds (n 185). Interventions: Sequential assignment to three isocaloric, isonitrogenous diets was performed as follows: standard 1-kcal/mL feeds with added protein (group 1), standard feeds with the addition of 20 – 40 g/day (0.6 g/kg/day) glutamine (group 2), or an immune-modulated formula with similar addition of glutamine (group 3). The goal for all patients was 25–30 kcal/kg/day and 2 g/kg/day protein. Measurements and Main Results: Patients were followed until discharge from the hospital. The primary end point was inhospital mortality, and multiple secondary end points were recorded. In-hospital mortality for group 1 was 6.3% (four of 64) vs. 16.9% (ten of 59, p .09) for group 2 and 16.1% (ten of 62, p .09) for group 3. After controlling for age and severity of illness, the difference in mortality between patients receiving standard tube feeds and all patients receiving glutamine was not significant (p < .11). There were no statistically significant differences between the groups for secondary end points. Conclusions: The addition of glutamine to standard enteral feeds or to an immunomodulatory formula did not improve outcomes. These findings suggest that enteral glutamine should not be routinely administered to patients with surgical critical illness. (Crit Care Med 2005; 33:2501–2506)
Options for statistical classification of buried objects from spatially sampled time or frequency domain EMI data

Methods for classifying objects based on spatially sampled electromagnetic induction data taken in the time or frequency domain are developed and analyzed. To deal with nuisance parameters associated with the position of the object relative to the sensor as well as the object orientation a computationally tractable physical model explicit in these unknowns is developed. The model is also parameterized by a collection of decay constants (or equivalently Laplace-plane poles) whose values in theory are independent of object position and orientation. These poles can be used as features for classification. The overall algorithm consists of two stages. First we estimate the values of the unknown parameters and then we do classification. Three classification schemes are examined. The first is based on data residuals. The second uses estimated pole values. The third is a blending of the first two. Preliminary results on synthetic data indicate the robustness of the pole estimates as features for classification and point toward the need for further analytical as well as experimental evaluation of the proposed methods.
A proof of the asymptotic normality of the inverse sampling estimator in finite population sampling

A proof of the result in the title is not, to the author's knowledge, presently available. Hence, one is given here.
Cognitive effects of unilateral brain lesions secondary to penetrating missile wounds.

The WAIS verbal and nonverbal subtest performance of Ss with unilateral brain lesions secondary to penetrating missile wounds was examined and compared with that of normal controls. The performance of matched right- and left-hemisphere lesion Ss differed significantly on only two verbal and one nonverbal measures, however, all performance differences were in the direction hypothesized. The performance of right-hemisphere lesioned and control Ss differed significantly on all measures, with consistently lower scores by brain-injured Ss, while the performance of left-hemisphere and control Ss differed significantly on the three verbal measures and WAIS Full Scale IQ. These results are in general agreement with previous reports using a similar research design and tend to support the hypothesis of differential impairment of verbal and nonverbal test performance in Ss with unilateral brain lesions.
To the public‐listed companies, from the investment community

Reporting the value of intellectual capital (IC) in the disclosure process for stakeholders has focused largely on the construction of indicators determined by the companies. This paper reports a study conducted with the investment community to determine the information they need to assist them in making investment decisions. This research project sets out to answer what are the perceptions towards strategic capital information required to assist in decision making and what are perceived as the most important or critical strategic management capital and strategic marketing capital indicators. More specifically, the study addresses the inter‐relationship between the knowledge of indicators and the perceived importance of disclosing the information on these indicators.
Detection and localization of magazine insertion clicks in various environmental noises.

The early detection and accurate localization of threatening sounds is vital for the survival of military personnel. The purpose of the present study was to investigate the detection, localization, and response time to an M-16 rifle magazine insertion click in three background conditions: jungle, pink, and ambient noise. The level of the click varied from -18 to 0 dB signal-to-noise ratio (SNR). Reported results indicate that detection rates of 50, 70, and 100% required SNRs of −6 to −12, −3, and 0 dB, respectively. Localization accuracy of 50 and 80% within a ±15° angle required SNRs of about −6 and 0 dB, respectively; 100% accuracy was never achieved. Response time was about 2.0–2.5 s for high SNRs but increased gradually at poorer SNRs. The military relevance of the reported findings is discussed.
Glycohydrolases as markers of hepatic ischemia-reperfusion injury and recovery

Advances in liver surgery and transplantation have lead to a steady increase in the number of these interventions. Prompt quantitative assessment of hepatic of hepatic function and a patient's subsequent morbidity and mortality following surgery remain difficult despite the currently utilized historic markers of hepatic parenchymal injury (e.g., aspartate transaminase [AST], lactate dehydrogenase [LDH] gamma-glutamyl transpeptidase [GGT]). Increases in serum glycohydrolase activities appear to provide sensitive and quantitative markers of hepatic ischemia/reperfusion injury. In 10 male swine (25 to 35 kg body weight) following 30, 45, and 90 minutes of acute hepatic ischemia, the systemic release of eight different glycohydrolases and lipid peroxides into serum were determined and compared with pre- and postischemic serum levels of LDH, GGT, and AST. The rapid release of glycohydrolases into serum was directly proportional to the length of the ischemic period from 30 to 90 minutes; e.g., beta-glucosidase, mean 1.9-fold increase at 30 minutes; 8.3-fold at 45 minutes; and 22.8-fold at 90 minutes; P < .002) and the activities peaked within the first 3 hours postischemia. In constrast, AST, LDH, and GGT were released slowly and peaked 20 to 30 hours after hepatic blood flow was restored. In swine with fatal outcomes (90 minutes of ischemia), all enzyme levels increased continuously during the final hours of life. However, in swine that survived hepatic ischemia/reperfusion injury (45 minutes of ischemia) the glycohydrolases, but not AST, LDH, and GGT, declined after 2 to 3 hours' postischemia and the serum lipid peroxide levels followed the same pattern. Serum beta-galactosidase and beta-glucosidase levels are sensitive markers that rise as quickly as traditional enzyme markers (AST, LDH, GGT) following hepatic ischemic injury; moreover, the glycohydrolases have the added value of serving as predictors of survival.
Eldercare and job productivity: An accommodation analysis

Over the next decade, the number of working adults relegated to the role of caregiver for one or more elderly family members will rapidly surge. The emotional, physical, and financial stress of caregiving has already begun to impact the productivity of the employee elder caregiver in the workplace, with estimates placing the annual costs around $30 billion. We can expect costs to grow as workers and their elderly parents continue to age. This particular study addresses the fundamental research question of what affects the job performance of employee elder caregivers. The results support the conclusion that the relationship among caregiving, personal support, organizational accommodation, and job productivity is multidimensional. Organizations attuned to the demands of elder caregiving can work with affected employees to reduce or eliminate declines in job productivity. Future researchers and practitioners can reconsider their research protocols and interventions along a wide continuum of interactions in the employee's home and workplace environments.
Essential hypertension of Caribbean Hispanics: sodium, renin, and response to therapy.

Little is known about essential hypertension in Hispanic Americans, despite the fact that they are the fastest-growing minority in the United States and have a disproportionate degree of hypertensive target organ damage. The authors studied 89 Caribbean Hispanic hypertensive patients who participated in six double-blind, randomized trials of antihypertensive agents. Demographics, laboratory data, sodium excretion, plasma renin activity, and atrial natriuretic peptide were obtained after 3–4 weeks on placebo. Blood pressure responses to angiotensin-converting enzyme (ACE) inhibitors, β blockers, calcium channel blockers, hydrochlorothiazide (HCTZ), and fixed combinations of ACE inhibitors and HCTZ, were compared to the placebo values after 8–12 weeks of treatment. Patients had a multiple risk factor profile (obesity and diabetes) and a wide spectrum of blood pressure elevation, left ventricular hypertrophy, and hypertensive renal damage. Urine sodium excretion rates indicated inability to comply with salt restriction in 65% of patients. Plasma renin activity was lower than that of Hispanic normotensive controls, and 62% of patients had low-renin essential hypertension by renin profiling to sodium excretion. On analysis of variance, blood pressure reductions by calcium channel blockers, HCTZ, and ACE inhibitor/HCTZ combinations were significantly greater than that with placebo, while those of ACE inhibitors and β blockers as monotherapy were not. The authors conclude that essential hypertension of Caribbean Hispanics is associated with multiple risk factors and is largely of the low-renin type. Responses to therapy are consistent with those observed in other populations with the low-renin phenotype and suggest salt-sensitivity of blood pressure in this population. Confirmation of the latter has implications for prevention and treatment of essential hypertension in Hispanics.
Antibody Response of Chickens to Sheep Red Blood Cells: Crosses Among Divergently Selected Lines and Relaxed Sublines

Crosses were made among lines of chickens that had undergone 30 generations of selection for high or low antibody response 5 d after an intravenous injection with SRBC, and between sublines in which selection was relaxed in generation 24. Antibody responses at 5, 10, and 14 d after injection were measured in the 4 lines and in reciprocal crosses among them. Divergence between the high and low lines selected for SRBC antibody was immediate and increased during selection. Although significant in both cases, separation of the relaxed subline from its respective selected line was greater in the high than the low line. Five-day SRBC titers of the relaxed lines and the crosses were intermediate to the high and low selected lines, with the direction and magnitude of heterosis being line dependent. A high proportion of chickens from low line mating combinations did not have detectable antibody titers at 10 and 14 d postinoculation with SRBC, precluding statistical analysis of these data. Results are discussed in the context of intra- and interlocus effects on the selected trait.
Comment on: “Polar plumes and fine‐scale coronal structures — On the interpretation of coronal radio sounding data” by Pätzold and Bird

Radio occultation measurements, which probe electron density over a wide dynamic range with high sensitivity and high spatial and temporal resolution reveal a solar corona permeated by a hierarchy of filamentary structures.
Asymmetric synthesis of two new conformationally constrained lysine derivatives

Abstract The asymmetric synthesis of the conformationally constrained l - and d -lysine derivatives methyl (1S,8S)-1-amino-8-tert-butoxycarbonylamino-1,2,3,4,5,6,7,8-octahydroanthracene-1-carboxylate ( 4 ) and methyl (1R,8S)-1-amino-8-tert-butoxycarbonylamino-1,2,3,4,5,6,7,8-octahydroanthracene-1-carboxylate ( 5 ), respectively are described. Application of the Bucherer hydantoin synthesis to the carbonyl group of 2′,3′,4′,5′,6′,7′-hexahydrospiro[1,3-ethylenedithiole-2,1′-anthracen]-8′-one ( 18 ), which was prepared from 1,8-dichloroanthraquinone ( 14 ) in nine steps and the deprotection of the masked second ketone of 18 yields rac-21. The latter is the precursor for a novel asymmetric reductive amination protocol using (R)-phenylglycinol as a chiral amino auxiliary and NaBH(OAc)3 as a reducing agent. Using this procedure, the asymmetric reductive amination of α-tetralone derivatives and indanone proceeds with >95% de. Lower diastereomeric excesses are observed for benzosuberone (16.7% de) and acetophenone (27.3% de). rac-21 gave (1′S,8′S,1(R)-25a (38% yield) and (1′R,8′S,1(R)-25b (44.5% yield) with greater than 52 and 78% de, respectively. Cleavage of the amino auxiliary of (1′S,8′S,1(R)-25a and of (1′R,8′S,1(R)-25b with lead(IV) tetraacetate and hydrolysis of the hydantoin ring yields the unprotected analogs of 4 and 5 . The latter are transformed into the selectively protected target molecules 4 and 5 through standard protection procedures. The overall yield of the 17- and 18-step synthesis starting from 13 was 0.3% yield for each constrained lysine derivative.
Glass ionomers for infants, children, and adolescents.

When practitioners fully understand the nature o f the glass ionomer materials and use them within their limitations, their use can improve the quality of restorative dental care for young patients. The materials for young patients can be classified as luting cements, dentin replacement liners and bases, and glass ionomer dentin and enamel restorative material. Future research efforts should be directed toward improving the glass ionomer cement by increasing fracture toughness and wear resistance, decreasing hardening time, and simplifying the sensitive handling technique.
From mouse to human: evolutionary genomics analysis of human orthologs of essential genes.

Understanding the core set of genes that are necessary for basic developmental functions is one of the central goals in biology. Studies in model organisms identified a significant fraction of essential genes through the analysis of null-mutations that lead to lethality. Recent large-scale next-generation sequencing efforts have provided unprecedented data on genetic variation in human. However, evolutionary and genomic characteristics of human essential genes have never been directly studied on a genome-wide scale. Here we use detailed phenotypic resources available for the mouse and deep genomics sequencing data from human populations to characterize patterns of genetic variation and mutational burden in a set of 2,472 human orthologs of known essential genes in the mouse. Consistent with the action of strong, purifying selection, these genes exhibit comparatively reduced levels of sequence variation, skew in allele frequency towards more rare, and exhibit increased conservation across the primate and rodent lineages relative to the remainder of genes in the genome. In individual genomes we observed ∼12 rare mutations within essential genes predicted to be damaging. Consistent with the hypothesis that mutations in essential genes are risk factors for neurodevelopmental disease, we show that de novo variants in patients with Autism Spectrum Disorder are more likely to occur in this collection of genes. While incomplete, our set of human orthologs shows characteristics fully consistent with essential function in human and thus provides a resource to inform and facilitate interpretation of sequence data in studies of human disease.
The effects of crossing trajectories on the dispersion of particles in a turbulent flow

The effects of ‘crossing trajectories’ and inertia on the dispersion of particles suspended in a field of grid-generated turbulence were investigated experimentally. The effect of particle trajectories crossing the trajectories of fluid elements, under the influence of a potential field (usually gravity), is to force the particles from one region of highly correlated flow to another. In this manner, particles lose velocity correlation more rapidly than the corresponding fluid points and as a result disperse less.A homogeneous decaying turbulent field was created behind a square biplanar grid in a wind tunnel. Particles were charged by a corona discharge then passed into the test section through a small plastic tube. A uniform electric field within the test section was used to simulate the effect of gravity, forcing the charged particles out of regions of correlated fluid at a higher than normal rate, therefore inducing the effects of crossing trajectories. Two sizes of glass beads (5 μm and 57 μm diameter) were employed in order to observe inertial effects. Laser-Doppler anemometry was used to measure particle mean-square displacement, autocorrelation coefficient, and mean-square velocity, from which dispersion coefficients were calculated.For the two particle sizes used in the tests, it was found that the particle diffusion coefficient, after a suitably long time from their release, was influenced primarily by the effect of crossing trajectories. Only in the particle mean-square velocity was the particle inertia seen to have any effect. The ratio of the particle relaxation time to the Kolmogoroff timescale was found to be a good indicator for the effects of particle inertia.
Phylogeny of the Island Populations of the HawaiianDrosophila grimshawiComplex: Evidence from Combined Data

The picture-winged species Drosophila grimshawi is unique among Hawaiian Drosophila in its wide geographic range, having populations on several islands of the Hawaiian archipelago. This distribution contrasts with the pattern of single-island endemism observed in most of the picture-winged group; significantly, it does not concur with predictions of the founder theory, where speciation is the typical outcome of founder events involving colonization of a new island. To examine this anomalous situation, we have taken a phylogenetic approach in an attempt to resolve the relationships among taxa and decipher the most probable colonization scenario. We have obtained both morphological and molecular data for all the D. grimshawi populations as well as the closely related species D. pullipes, and two outgroup species, using scanning electron microscopy to score ultrastructural features of the chorion or eggshell, and PCR amplification and nucleotide sequencing to acquire sequence data on Yp1, one of the three Yolk protein genes. In addition, we have used available data on Yolk Protein electrophoretic pattern and jousting, oviposition, and mating behavioral characters. Analyses of these data sets, either individually or in combination, indicate that there are two separate and ecologically distinct clades within this species complex. One clade includes the Kauai and Oahu populations of grimshawi, as well as the closely related species D. pullipes from Hawaii, all of which are classified as ecological specialists with respect to their oviposition and breeding substrate. The other clade includes all the ecologically generalist grimshawi populations of the Maui Nui island complex. The phylogenetic results do not concur with the previously proposed hypothesis that D. pullipes originated from a founder derived from the Maui Nui complex and further suggest that these taxa are in need of taxonomic revision.
Bibliographic organization of U.S. federal depository collections

Abstract The importance of government documents continues to increase each year; the Government Printing Office projects a 10% annual increase in sales over the next five years. Extensive and in-depth research on accessibility to federal documents in small. This mail survey—conducted in 1979–1980—sought to provide reliable data on staff size and type, collection size and arrangement, and methods employed to provide descriptive and subject access to federal documents in the depository system. A two-page questionnaire was sent to all depository libraries (1,218) and information was received from 737 respondents. Results indicated that on the average about 40% of depository items were being selected yearly and arranged in some form of separate collection. One professional librarian, a clerk, and some student help were assigned to documents. On the average, the librarian and clerk were assigned for no more than one-third of their weekly work time; student help was available for approximately 20 hours per week. Generally, increasing the size of staff does not mean greater descriptive or subject access to federal documents. One in four libraries does not provide any descriptive access; less than 6% of the libraries provide some subject access. Computer technology (particularly in the form of on-line bibliographic services) is modestly used; only one-third of the respondents indicated such services were available. There is no clear relationship between increased selection of federal documents and increased use of on-line services, except in those libraries claiming totally separate collections.
Rearing a native cactus moth, Melitara prodenialis (Lepidoptera: Pyralidae), on artificial diet and Opuntia cladodes: Preliminary comparisons

Summary This study compared several biological parameters of native cactus moth, Melitara prodenialis, reared on an artificial versus the natural diet of Opuntia spp. cladodes. Results suggest that the current artificial diet developed for mass rearing C. cactorum can provide nutritional value for the rearing of Melitara spp. native cactus moths. Overall, rearing M. prodenialis on the artificial diet was more successful than on Opuntia cladodes and required less time and labor. Mass rearing of M. prodenialis using artificial diet should improve once sub sequent generations become adapted to laboratory rearing conditions.
NMR relaxation time in Landau Fermi liquid theory

Abstract In the normal phase of bulk 3 He, the Landau theory of Fermi liquids has long served as an adequate model. Here, the theoretical predictions for the nuclear magnetic relaxation times are discussed.
Studies on bromobenzene‐induced hepatotoxicity using in vivo MR microscopy with surgically implanted RF coils

Using surgically implanted RF coils at 300 MHz, three-dimensional microscopic MR images of rat liver were obtained in vivo to follow the development of pathology induced by bromobenzene exposure. Formalin fixed specimens of liver from these animals were also imaged using in vitro MR microscopy, followed by conventional optical microscopy. All MR images were acquired using a spin-warp pulse sequence with TR = 950 ms and TE = 23 ms. The in vivo images were reconstructed as 256(2) x 32 arrays with a voxel size of (50 microns)2 x 219 microns, while the in vitro images were reconstructed as 256(2) x 128 arrays, giving an isotropic resolution at (39 microns)3. Based on results from six animals, we have found in all animals exposed to bromobenzene, image intensity decreased in specific hepatic tissue regions. These regions were well correlated to low signal intensity areas observed in in vitro MR images at higher resolution. Conventional optical microscopy indicated that the low signal intensity regions corresponded to areas of necrosis. The decrease in signal intensity is consistent with increased local diffusion coefficients as a result of necrosis. This study demonstrates that MR microscopy with implanted RF coils can be successfully used to follow tissue pathological changes in living tissues.
Desktop publishing and medical imaging: Paper as hardcopy medium for digital images

Desktop-publishing software and hardware has progressed to the point that many widely used wordprocessing programs are capable of printing highquality digital images with many shades of gray from black to white. Accordingly, it should be relatively easy to print digital medical images on paper for reports, instructional materials, and in research notes. Components were assembled that were necessary for extracting image data from medical imaging devices and converting the data to a form usable by word-processing software. A system incorporating these components was implemented in a medical setting and has been operating for 18 months. The use of this system by medical staff has been monitored.
Reproducibility of 3D proton spectroscopy in the human brain.

The inter- and intrasubject reproducibility of the metabolite levels of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho), obtained with three-dimensional (3D) multivoxel proton spectroscopy (1H-MRS), was analyzed in eight healthy volunteers. Serial, back-to-back measurements on a phantom showed the methodology and instrumentation to be highly reproducible, with a median coefficient of variation (CV) of 3.8%. In the human brain, the metabolite levels' variability was larger, with intrasubject median CVs for a total of 1876 signal voxels of 13.8%, 18.5%, and 20.1% for NAA, Cr, and Cho, respectively. These variations possibly arise from small, unavoidable, ±1–2 mm volume-of-interest (VOI) repositioning uncertainties, which vary each 0.75-cm3 voxel's partial fluid/gray/white-matter fractions. Comparing the CVs between eight subjects in a total of 324 selected voxels gave total interindividual CVs of 15.6%, 23.3%, and 24.4%, compared with intraindividual CVs in the same voxels of 14.4%, 14.8%, and 15.3%, for NAA, Cr, and Cho, respectively. Replacing the signal(s) from each voxel by the average of itself with its six canonical neighbors reduces the intrasubject median CVs to 8.3%, 9.5%, and 9.7%. The measurement uncertainties can be reduced at a cost of either spatial resolution (by using larger voxels) or time (by performing serial follow-ups). Magn Reson Med 47:439–446, 2002. © 2002 Wiley-Liss, Inc.
Atmospheric Influences on Q-Switched Laser Sampling and Resulting Plumes:

When a 10–100-mJ single-spike Q-switched Nd laser pulse is focused on a copper sample, the presence of an atmosphere affects the spectra, the crater size, and the amount of sample vaporized. At 760 Torr the crater diameter (90 μ) and amount of sample vaporized (35 ng) remain relatively constant while at 1 Torr they both increase with increasing laser energy. Spatial changes in the spectra occur with changes in ambient pressure. The continuum intensity of the limited region just above the sample surface appears to be a better measure of the energy reaching the sample than does the energy of the laser beam. The experimental results appear to be caused by absorption of a large fraction of the laser energy in an atmospheric plasma. A radiation-supported shock-wave model is evaluated in detail and compared briefly with similar models as possible mechanisms for production of the atmospheric plasma. The analytical chemical implications of the experimental and theoretical results are discussed.
Determination Of A Variable-Spacing Array's Applicability As The NASA Advanced Communication Test Satellite Intersatellite Communication System Transmitter

Direct detection free-space optical communication using laser diode transmitters has been proposed for use on NASA's Advanced Communication Test Satellite (ACTS). The investigation reported here examines a prototype laser diode array for this purpose, having a variable spacing between the emitter stripes (VSA). The device was designed to output a moderately powerful beam into a narrower single-lobed radi-ation pattern than that of the (currently) more powerful regular-spacing phase-locked arrays (RSAs). Key parameters were measured to determine whether the VSA would be a good candidate for use in the ACTS system. Measurements showed a superior electrical frequency response, superior impulse response, and a slightly narrower far-field radiation pattern compared with the RSA. However, the limited output power of the VSA realistically precludes its use in a free-space optical communication system even when a polarization beam-combining system is used.
African–Americans, Hispanic Americans, and Non-Hispanic Whites Without GERD or Reflux Symptoms Have Equivalent 24-h pH Esophageal Acid Exposure

Background Ambulatory esophageal pH monitoring is, currently, the recommended diagnostic exam for gastroesophageal reflux disease. Data are currently available for African–American (AA) and non-Hispanic white (nHw) volunteers among United States ethnic groups. The purpose of this study was to obtain normal values of 24-h esophageal pH by monitoring healthy adult Hispanic American (HA) volunteers and to compare these with values obtained from healthy AA and nHw volunteers to determine if ethnic variation exists in 24-h esophageal pH.