cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of Change in Physical Activity on Physical Function Limitations in Older Women: Mediating Roles of Physical Function Performance and Self-Efficacy

OBJECTIVES: To examine the hypothesis that changes in self-efficacy and functional performance mediate, in part, the beneficial effect of physical activity on functional limitations over time. DESIGN: Prospective, observational study. SETTING: Community-based. PARTICIPANTS: Two hundred forty-nine community-dwelling older women. MEASUREMENTS: Participants completed measures of self-reported physical activity, functional limitations, and self-efficacy. Four measures of physical function performance were also assessed. Measures were completed at baseline and 24 months. Data were analyzed using a panel model within a covariance modeling framework. RESULTS: Results indicated that increases in physical activity over time were associated with greater improvements in self-efficacy, which was associated in turn with improved physical function performance, both of which mediated the association between physical activity and functional limitations. Fewer functional limitations at baseline were also associated with higher levels of self-efficacy at 24 months. Age, race, and health status covariates did not significantly change these relationships. CONCLUSION: The findings support the mediating roles of self-efficacy and physical function performance in the relationship between longitudinal changes in physical activity and functional limitations in older women.
Development of an extended proper orthogonal decomposition and its application to a time periodically forced plane mixing layer

Two extensions of the classical proper orthogonal decomposition (POD) methodology exposited by Lumley for turbulent flows are presented. First, the extended POD (EPOD) can deal with flows lacking statistical stationarity by summing the velocity correlations of an ensemble of time series. Thus it reduces to the classical POD for a statistically stationary flow, and to the ‘‘snapshot’’ of Sirovich for data from a single instant in each realization of an ensemble. Second, the EPOD can deal with flows having one or more length scales exceeding the spatial range over which simultaneous measurements can be made, by generating composite modes using nonsimultaneous, spatially overlapping data. Both new capabilities have been exercised by applying the EPOD to the streamwise velocity component measured by a cross‐stream hot‐wire rake in an anharmonically forced turbulent plane mixing layer that is not statistically stationary, and is statistically homogeneous in only one direction. It is discovered that as few as three one‐dimensional modes are capable of capturing as much as 78% of the ‘‘action’’ in data from ten wires in a cross‐stream rake.
Robotic Surgery for Gastrointestinal Malignancies

Background This report describes our initial experience with the use of robotic-assisted surgery for the treatment of gastrointestinal (GI) malignancies. Methods Between November 2004 and July 2007, 73 robotic procedures (26 female, 47 male) for GI cancer were performed and retrospectively reviewed. Procedures included 25 oesophagectomies, 11 gastrectomies and 37 rectal resections. The median body mass index (BMI) for this patient population was 26. Results The median operative times for rectal, oesophageal and gastric resections were 285, 482 and 430 min, respectively. There were three conversions. Major postoperative morbidity was 16% for rectal, 32% for oesophageal and 9% for gastric procedures. The leak rate was 11% for rectal, 16% for oesophageal and 9% for gastric anastomoses. Median length of stay was 4, 11 and 5 days, respectively. The median number of lymph nodes harvested was 13, 22, and 26 for rectal, oesophageal and gastric lymphadenectomies, respectively. At a median follow-up of 9 months, one patient developed a port site recurrence; 30 day mortality was zero. Conclusion This initial experience suggests that the robotic approach is safe and feasible for a variety of radical oncological surgical procedures. Copyright © 2007 John Wiley & Sons, Ltd.
A Census of Eddy Activities in the South China Sea During 1993-2007

[1] Numerous mesoscale eddies occur each year in the South China Sea (SCS), but their statistical characteristics are still not well documented. A Pacific basin-wide three-dimensional physical-biogeochemical model has been developed and the result in the SCS subdomain is used to quantify the eddy activities during the period of 1993–2007. The modeled results are compared with a merged and gridded satellite product of sea level anomaly by using the same eddy identification and tracking method. On average, there are about 32.9 ± 2.4 eddies predicted by the model and 32.8 ± 3.4 eddies observed by satellite each year, and about 52% of them are cyclonic eddies. The radius of these eddies ranges from about 46.5 to 223.5 km, with a mean value of 87.4 km. More than 70% of the eddies have a radius smaller than 100 km. The mean area covered by these eddies each year is around 160,170 km2, equivalent to 9.8% of the SCS area with water depths greater than 1000 m. Linear relationships are found between eddy lifetime and eddy magnitude and between eddy vertical extent and eddy magnitude, showing that strong eddies usually last longer and penetrate deeper than weak ones. Interannual variations in eddy numbers and the total eddy-occupied area indicate that eddy activities in the SCS do not directly correspond to the El Nino–Southern Oscillation events. The wind stress curls are thought to be an important but not the only mechanism of eddy genesis in the SCS.
Interlayer micromechanics of the aortic heart valve leaflet

While the mechanical behaviors of the fibrosa and ventricularis layers of the aortic valve (AV) leaflet are understood, little information exists on their mechanical interactions mediated by the GAG-rich central spongiosa layer. Parametric simulations of the interlayer interactions of the AV leaflets in flexure utilized a tri-layered finite element (FE) model of circumferentially oriented tissue sections to investigate inter-layer sliding hypothesized to occur. Simulation results indicated that the leaflet tissue functions as a tightly bonded structure when the spongiosa effective modulus was at least 25 % that of the fibrosa and ventricularis layers. Novel studies that directly measured transmural strain in flexure of AV leaflet tissue specimens validated these findings. Interestingly, a smooth transmural strain distribution indicated that the layers of the leaflet indeed act as a bonded unit, consistent with our previous observations (Stella and Sacks in J Biomech Eng 129:757–766, 2007) of a large number of transverse collagen fibers interconnecting the fibrosa and ventricularis layers. Additionally, when the tri-layered FE model was refined to match the transmural deformations, a layer-specific bimodular material model (resulting in four total moduli) accurately matched the transmural strain and moment-curvature relations simultaneously. Collectively, these results provide evidence, contrary to previous assumptions, that the valve layers function as a bonded structure in the low-strain flexure deformation mode. Most likely, this results directly from the transverse collagen fibers that bind the layers together to disable physical sliding and maintain layer residual stresses. Further, the spongiosa may function as a general dampening layer while the AV leaflets deforms as a homogenous structure despite its heterogeneous architecture.
Spinning knots about submanifolds; spinning knots about projections of knots

Abstract A method is defined and discussed for constructing higher dimensional codimension two knots. These methods generalize the various known methods of spinning of knots. Although the focus is on knotted sphere pairs, the methods more generally provide a method of producing a variety of knottings from any given codimension two pair of manifolds.
Marihuana and driving among teenagers: Reported use patterns, effects, and experiences related to driving☆

Abstract Forty-nine per cent of 1271 incoming college freshmen reported using marihuana during the previous year. A majority of marihuana users simultaneously consume alcohol at least on occasion, and many of them have enough alcohol at those times to be impaired by the alcohol alone. Among users who smoke weekly or more often one-quarter of driving while “high” occurs under the combined effect of marihuana and medium to heavy alcohol use. Most users reported marihuana effects on driving judged to be hazardous, such as altered attention, vision or time perception. In an estimated 15,000 driving trips while “high” on marihuana two crashes occurred definitely attributable and two possibly attributable to marihuana use. Also, 42 persons (13 per cent of drivers) reported near crashes while “high”. Since this is not a comparison study, it is not known whether or not this reported experience is excessive for this age group. Drivers who encountered trouble while driving after marihuana said 59 per cent of the time that the incidents were caused by the marihuana, 27 per cent by alcohol, and in 14 per cent that they couldn't assess which drug was responsible.
Weathering the influenza vaccine crisis.

What is likely to be the effect of reduced vaccination coverage in the United States this year? Dr. John Treanor explains the urgent need for more vaccine.
The growth rate of submarine volcanoes on the South Honshu and East Mariana ridges — Comments

Abstract Growth rates, recently reported for eleven submarine volcanoes of the Mariana arc, are probably in error by several orders of magnitude. The reported growth rates are based solely on comparison of bathymetric surveys done by different methods over a 15–20-year time span. We have additional data on three of the volcanoes which argue against the inferred high growth rates. A detailed seismic reflection survey of one edifice (Fukujin Seamount) reveals that it has a very sharp peak which would be difficult to detect by more regional-scale sonar surveys. Examination of side-scan sonar images and bottom photography, and the recovery of highly weathered rocks in dredge hauls from another volcano (Kasuga Seamount), which is presumed to have grown almost 200 m in height in the last 17 years on the basis of bathymetric surveys, show it to be most likely extinct. Alvin submersible dives, as well as bottom photography and sonar images, on a third seamount (South Kasuga) show processes at its summit to be mainly erosional rather than constructional even though it is considered to be active. The inferred average growth rates of 15 m/y in height for six of the eleven volcanoes located in the northernmost part of the Mariana arc imply a volumetric volcanic production rate for this 500-km-long section of the arc of up to 9 km 3 /y which exceeds the estimated global rate for all subduction zones. We believe that navigational errors and lack of total coverage over the summits of these seamounts are the main causes of the apparent differences in their minimum shoal depths between different survey methods.
K-Homology, Asymptotic Representations, and Unsuspended E-Theory

Connes and Higson defined a bivariant homology theory E(A, B) for separable C*-algebras. The elements of E(A, B) are taken to be homotopy classes of asymptotic momorphisms from SA ⊗ K to SB ⊗ K. In symbols E(A, B) ≅ [[SA, SB ⊗ K]]. If A is K-nuclear then E-theory agrees with Kasparov′s bivariant K-theory. We show that, in many cases, one need not take suspensions to calculate the E-theory group E(A, B). For many A, we show E(A, B) ≅ [[A, B ⊗ K]] for all B. Among the A for which this is true are C0(X\{pt}) for X with the homotopy type of a finite, connected CW complex. This gives a concrete realization of K-homology, related to the Brown-Douglas-Fillmore description. For example, K0(X) arises as asymptotic representations, K0(X) ≅ [[C0(X), K]]. Other A for which our isomorphic holds include the nonunital dimension-drop intervals. In this case, there is no distinction between ∗-homomorphisms and asymptotic morphisms so we have succeeded in classifying all ∗-homomorphisms from a dimension-drop interval to a stable C*-algebra. This was subsequently used by Elliott (J. Reine Angew. Math.443 (1993), 179-219) in the classification of certain C*-algebras. The dimension-drop interval may also be used to describe K*(X; Z/n) in terms of paths of asymptotic representations of C0(X).
Restriction-Endonuclease Analysis of DNA from 15 Giardia Isolates Obtained from Humans and Animals

The DNA banding pattern of 11 human and four animal isolates (two beaver, one cat, and one guinea pig) of Giardia were compared by using two related techniques. Patterns were compared after endonuclease restriction of DNA followed by agarose gel electrophoresis and ethidium bromide staining and after Southern blot analysis using recombinant plasmids containing Giardia DNA as probes. Two major groups could be distinguished with ethidium bromide staining of eight isolates. Southern blot analysis, however, could distinguish nine different patterns among the 15 isolates studied. One common banding pattern was seen in six isolates (two animal and four human); the remainder of the isolates were unique, with the exception of two identical isolates from sisters. Three isolates (one from a beaver and two from humans) were markedly different from Giardia with the common banding pattern, whereas the other six unique isolates varied moderately. Beavers and other mammals do not seem to possess their own species of Giardia. This methodology introduces a way of distinguishing one species of Giardia isolate from another and promises to be helpful in epidemiological investigations.
Bond orders and valencies from ab initio wavefunctions: application to prototypical molecules and to the characterization of solitons in polyenes

Abstract Recent improved definitions of bond order and valencies are reviewed. Extensive tests of the determination of these properties from ab initio wavefunctions are reported, using prototypical molecules, such as methyl radical, ethylene, acetylene, water and hydrogen fluoride. The extension of these definitions to the unrestricted Hartree-Fock and post Hartree-Fock levels of theory are discussed. The concepts are applied to the study of charge carrier defects in large polyene molecules. Post Hartree-Fock calculations are carried out at the MC SCF level of theory using a complete π active space for the C 5 H 7 , C 7 H 9 , C 9 H 11 and C 11 H 13 radicals. The fully optimized structures are reported and their electronic properties analyzed in terms of bond orders.
Procedural Competency in Emergency Medicine: The Current Range of Resident Experience

. Objectives: To evaluate the recorded range of procedures tracked by emergency medicine (EM) programs, and to determine whether differences in procedural experience occur in various types of residency or hospital settings. Methods: The program directors of 112 approved EM programs were asked to send actual procedure logs. The requested information included the average total number of a given procedure per graduating resident, for all procedures that were tracked. Data were categorized by program format, hospital type, and ED volume. To assess the global procedural experience among programs, a set of 22 “index procedures” were identified; all procedures the EM residency review committee (RRC-EM) required to be tracked were included in this set. The means per graduating resident for each index procedure were added together to generate a “mean index procedure sum” (MIPS) per graduating resident for each residency program. These MIPSs for a residency were then compared by program format, hospital type, and ED volume. A similar analysis was performed for all resuscitations, and a “mean index resuscitation sum” (MIRS) per graduating resident was generated. Results: An overall response rate of 82% was achieved; a number of programs had not graduated a residency class and were not included. Sixty-five of 85 eligible programs (76%) provided procedural data. The average number of a given procedure per graduating resident (95% CI in parentheses) for selected procedures is as follows: oral intubation 65 (46 to 85), intubation unspecified 75 (62 to 87), nasal intubation 6 (4 to 9), cricothyroidotomy 2 (1 to 2), subclavian catheter 23 (16 to 30), chest tubes 17 (14 to 20), intraosseous line 2 (1 to 3), thoracotomy 3 (2 to 5), and vaginal deliveries 17 (13 to 21). The only statistically significant differences in subgroup comparisons were in diagnostic peritoneal lavage, trauma resuscitations, and pediatric medical resuscitations when compared by postgraduate year format, and intubation—unspecified and cricothyroidotomy when compared by hospital type. There was no statistically significant difference when MIPSs were compared by format, hospital type, or ED volume. Conclusions: To the authors' knowledge, this is the first study of the range of EM resident procedure experience across the spectrum of EM residency types and settings. Overall, there are few statistically significant differences in procedure experience among different program formats. Similar experiences are recorded in a variety of different hospital types or ED volumes. However, some programs report very limited EM resident experience with selected critical procedures. There is a large variation in the types and numbers of procedures recorded by EM programs.
The impact of a natural disaster on altruistic behaviour and crime.

Institutional altruism in the form of a public-sector intervention and support for victims and social altruism generated by mutual aid and solidarity among citizens constitute a coming together in a crisis. This coming together and mutual support precipitate a decrease in crime rates during such an event. This paper presents an analysis of daily fluctuations in crime during the prolonged ice storms in Quebec, Canada, in January 1998 that provoked an electrical blackout. Of particular interest are the principal crisis-related influences on daily crime patterns. A first series of analyses examines the impact of altruistic public-sector mobilisation on crime. A significant decline in property crime rates was noticed when cheques were distributed to crisis victims in financial need in Monteregie, and hence they were attributable to public intervention (institutional altruism). Moreover, the rate of social altruism (financial donations), which was more substantial in adjoining rather than distant regions, was inversely proportional to crime rates.
EXPRESSION OF SODIUM CHANNEL ALPHA - AND BETA -SUBUNITS IN THE NERVOUS SYSTEM OF THE MYELIN-DEFICIENT RAT

Using subtype-specific riboprobes and a non-isotope in situ hybridization technique, the pattern of expression of the mRNAs for voltage dependent sodium channel alpha-subunits I, II, III and NaG, and the beta 1-subunit were compared in myelin-deficient rats and unaffected male littermates. Tissues examined included the hippocampus, cerebellum, spinal cord and dorsal root ganglia. Previous studies have demonstrated that the expression of sodium channel alpha- and beta 1-subunits follows a distinct temporal and spatial pattern during development, characterized in part by greater expression of alpha-subunit III and its mRNA during development than in the adult. We examined animals of 20-22 days of age, a time when, according to earlier reports, the unaffected animals should nearly have reached an adult expression pattern. Normal male littermates were indeed found to express a sodium channel subunit mRNA pattern generally consistent with previous reports on adult rats. Myelin-deficient animals exhibited an expression pattern identical to the unaffected littermates, indicating that myelination is not required for the progression from the embryonic to the adult expression pattern of sodium channel subunits.
The upregulation of a glial cell surface antigen at the astrocytic scar in the rat

The upregulation of a 106-kDa glial protein was examined using indirect immunohistochemical methods. The protein is recognized by the monoclonal antibody AMP1. Previous studies demonstrated that the AMP1 antigen is found on the external surface of cultured astrocytes and is involved in stabilizing adhesive interactions between these cells. In sections of injured adult rat brain, the spatial distribution of the AMP1 antigen correlated with the region of reactive gliosis. The relative intensity of immunofluorescence indicates that the AMP1 antigen is dramatically upregulated at the gliotic scar. The correlation between AMP1 antigen upregulation and reactive gliosis suggests that this molecule is critical to the process of CNS scar formation.
Computational Approaches to Understanding the Mechanism of Transport in the Na+/Galactose Co-Transporter vSGLT

A number of recent high resolution structures suggest that a larger family of cation coupled substrate transporters share a common core architecture. At the molecular level, it is not known how this architecture enables them to harness the energy stored in ionic gradients to move small molecules across the membrane. We have studied the details of substrate and ion entry and exit to the cytoplasm of the galactose symporter vSGLT. We used equilibrium molecular dynamics (MD) simulations to determine the role of key residues in stabilizing galactose and sodium in their respective binding sites. The simulations show that the transporter is stable when simulated as a monomer having only small deviations from the x-ray structure. We also used steered MD simulations to pull galactose and sodium from their site into the cytoplasm to obtain the free energy for unbinding.
Sex differences in quantitative and analytical GRE performance: An exploratory study

The exploratory data analysis method of median polishing was used in this study to examine patterns of differences in male and female performance on the Graduate Record Examination quantitative and analytical tests. Consistent with results of previous studies using a younger cohort of students, males were found overall to outperform females on the quantitative measure but not on the analytical measure. However, this pattern was found not to be consistent across all undergraduate majors. Women in the engineering and physical science majors were found to perform higher on both measures than would be expected.
Variation of the Dielectric Constant of Rochelle Salt Crystals with Frequency and Applied Field Strength

The dielectric constant of Rochelle salt crystals perpendicular to the $a$ axis at 0\ifmmode^\circ\else\textdegree\fi{}C was measured over the frequency range of 30 to 30\ifmmode\times\else\texttimes\fi{}${10}^{6}$ cycles/sec. Following a fairly uniform decline from 62,000 at 30 cycles to 220 at ${10}^{7}$ cycles, the dielectric constant drops abruptly to negative values (inductive reactance) at 14\ifmmode\times\else\texttimes\fi{}${10}^{7}$ cycles. This frequency is independent of the size and mounting of the crystal and thus appears to be critical for this crystalline material.
Managing spatio-temporal complexity in hopfield neural network simulations for large-scale static optimization

A simulation methodology, which trades space complexity with time complexity, to create the Hopfield neural network weight matrix, the costliest data structure for simulation of Hopfield neural network algorithm for large-scale optimization problems, is proposed. Modular composition of a weight term of the Hopfield neural network weight matrix for a generic static optimization problem, which facilitates construction and reconstruction of the weights on demand during a simulation, is exposed. Proposed methodology is demonstrated on a static combinatorial optimization problem, namely the Traveling Salesman Problem (TSP), through the algebraic procedure for temporal (versus spatial) weight matrix construction, pseudo code and C/C++ code implementation, and an associated simulation study. The proposed methodology is successfully tested through simulation on a general purpose WindowsTM-AMDTM platform for up to 1000 city Traveling Salesman Problem instance, which would require approximately no less than 1TB of memory to be allocated simply to instantiate the weight matrix in the memory space of the simulation process.
Geometric and Material Optimization of Vortex-Induced Vibration Micro Energy Harvesters for Localized Wind Environments

Wind energy capture in today’s environment is often focused on producing large amounts of power through massive turbines operating at high wind speeds. The device presented by the authors performs on the extreme opposite scale of these large wind turbines. Utilizing vortex induced vibration combined with developed and demonstrated piezoelectric energy harvesting techniques, the device produces power consistent with peer technologies in the rapidly growing field of micro-energy harvesting. Vortex-induced vibrations in the Karman vortex street are the catalyst for energy production of the device. To optimize power output, resonant frequency of the harvester is matched to vortex shedding frequency at a given wind speed, producing a lock-on effect that results in the greatest amplitude of oscillation. The frequency of oscillation is varied by altering the effective spring constant of the device, thereby allowing for “tuning” of the device to specific wind environments. While localized wind conditions are never able to be predicted with absolute certainty, patterns can be established through thorough data collection. Sampling of local wind conditions led to the design and testing of harvesters operating within a range of wind velocities between approximately 4 mph and 25 mph. For the extremities of this range, devices were constructed with resonant frequencies of approximately 17 and 163 Hz. Frequency variation was achieved through altering the material composition and geometry of the energy harvester. Experimentation was performed on harvesters to determine power output at optimized fluid velocity, as well as above and below. Analysis was also conducted on shedding characteristics of the device over the tested range of wind velocities. Computational modeling of the device is performed and compared to experimentally produced data.Copyright © 2012 by ASME
Empirical model of dynamic shear modulus for surface marine sediments

Based on 770 laboratory measurements of void ratio (e) and effective overburden pressure (p) from the upper 2 m of sediments in Eckemfoerde Bay, Baltic Sea, a new empirical model for estimating dynamic shear modulus (μ) was developed as μ = b0 (p) b 1exp[ ‐b2e + b3 (1n p) 2 where b0 = 294.89, b1 = 0.0800, b2 = 0.0079, b3 = 0.0227, and R2 = 0.9571. The void ratio and effective pressure range from 2.01 to 10.03 and from 0.04 to 6.13 kPa, respectively. The results indicate that a new term of exp[bs (1n p)2] is needed in the model if the properties of surficial sediments are included. The shear wave velocities that were calculated from the new model are comparable to those measured in situ when the depth is more than 50 cm.
Spicing up the military: Use and effects of synthetic cannabis in substance abusing army personnel

Synthetic cannabis (SC) use has been increasing within the United States. Due to difficulties with its detection through standard testing, it may be an attractive substance of abuse for military personnel. However, few studies have examined the consequences of its use in this population, including evidence for its potential for abuse and dependence. Participants included 368 active-duty Army personnel who expressed interest in participating in a "check-up" around their alcohol or substance use, of whom 294 (80%) met DSM-IV criteria for substance abuse or dependence (including alcohol, illicit drugs, and prescription medications) and were not engaged in substance abuse treatment. Forty-one participants (11%) reported using SC in the last 90 days. Of those, 27 listed SC as their drug of choice. There were no significant differences in race, ethnicity, deployment history, or religion between SC users and others. Users of SC were generally younger and had less education and income than those who used only alcohol. Among SC users, 12% met criteria for drug abuse and 68% for dependence. Participants perceived SC use to be significantly more prevalent among military personnel than among civilians. Results suggest that SC is prevalent among substance-using soldiers and that DSM-IV criteria for abuse and dependence apply to SC. In addition, results highlight the importance of assessing and treating SC use among active-duty military personnel.
Interface stability in a slowly rotating, low gravity tank Experiments

Analytical models of liquid in partially-filled rotating tanks predict both the shape of the interface between the liquid and its vapor, and the stability of that interface. The models are of necessity incomplete and experimental data are needed to assess the approximations made. Presented are preliminary experimental studies both in the laboratory and in the low-gravity environment of a free-falling aircraft. Emphasis is placed on bubbles which intersect the container boundaries. Measurements of rotating equilibrium bubble shapes are in agreement with theoretical profiles derived from Laplace's formula. The interface shape depends on the contact angle, the radius of intersection with container, and the ratio of centrifugal force to surface tension.
Characterization of the membrane domain subunit NuoJ (ND6) of the NADH-quinone oxidoreductase from Escherichia coli by chromosomal DNA manipulation.

The ND6 subunit is one of seven mitochondrial DNA-encoded subunits of the proton-translocating NADH-quinone oxidoreductase (complex I). Physiological importance of the ND6 subunit is becoming increasingly apparent because a number of mutations leading to amino acid changes in this subunit have been found to be associated with known mitochondrial diseases. Using the Escherichia coli enzyme (NDH-1), we have investigated the NuoJ subunit (the E. coli counterpart of ND6) by employing a chromosomal DNA manipulation technique. A series of point mutations was constructed directly on the nuoJ gene in the chromosome targeting at highly conserved residues. Analyses with blue-native gel electrophoresis and immunological methods revealed that, in all point mutants, the assembly of NDH-1 was normal and that the deamino-NADH-K3Fe(CN)6 reductase activity of the membrane was essentially the same as that of the wild-type. However, energy-coupled NDH-1 activities were affected to varied extents. Among them, mutants of the ...
Large Molecular Hyperpolarizabilities in “Push−Pull” Porphyrins. Molecular Planarity and Auxiliary Donor−Acceptor Effects

Linear optical and SHG coefficients of a number of “push−pull” porphyrins are analyzed using the semiempirical INDO/S Hamiltonian and singles-only CI. The NLO response properties are computed at a nonresonant excitation energy of 0.1 eV using the correction vector formalism, and the calculations are carried out in both ideal planar and SYBYL force-field optimized geometries. The results strongly suggest that large NLO responses may be obtained by (1) minimizing the dihedral twist of phenyl substituents with respect to the porphyrin plane, (2) replacing the homoaromatic phenyl rings in tetraphenylporphyrins by electron excessive or deficient heteroaromatic rings such as pyrrole or tetrazine, (3) exploiting the electron-excessive and -deficient sites of the porphyrin π-electron bridge itself. Thus, functionalizing the electron excessive β position with donor substituents and electron-deficient meso position with acceptor substituents leads to enhanced NLO response properties. The enhancement in the NLO resp...
Information technology and U.S. policy: Strategic options for the eighties

Abstract The 1980's can be expected to experience a profound transformation in information technology and information services. These include: • a confluence of diverse technology; • multi-industry, multinational and multigovernment R & D participation; • productivity increases along a broad front; • innovation as a self-generating cycle of new products; • an acceleration in the innovation process; • an increase in product obsolescence; • the migration of cheap intelligence to the shop, home, office and store; • the proliferation of information networks - regional, national, international; • the erosion of traditional market boundary lines and distinctions. These developments confer a series of critical strategic options upon the public and the private sector in the United States. If public policy anticipates the future, broadens its portfolio, unleashes creative energy, rewards risk taking and abolishes traditional regulation, then the U.S. information economy will at least possess an opportunity to flourish in the decade of the 80's. If, on the other hand, policy continues its jurisdictional creep, stifles entry, regulates risks and penalizes entrepreneurship, then the U.S. economy risks forfeiting its future on the altar of tradition.
TEABr directed synthesis of ZSM-12 and its NMR characterization

Abstract Synthesis of ZSM-12 using tetraethylammonium bromide (TEABr) as the template was investigated. Among the various parameters that affect the crystallization of ZSM-12, aluminum content of the gel, OH − /SiO 2 and TEA/SiO 2 ratios were the important determinants. Systematic variations of these parameters revealed that the TEABr-assisted synthesis had many similarities to the synthesis using TEAOH template reported earlier, with the exception that the OH − /SiO 2 ratios had to be maintained at lower values. Furthermore, the OH − /SiO 2 ratios favorable for ZSM-12 formation lie in a very narrow range. The source of alkalinity also affected the rate of crystallization and the composition of the product. The crystallization was found to be faster and better incorporation of aluminum in the zeolite framework was obtained when NaOH was used to provide alkalinity rather than KOH. Successful synthesis of highly crystalline ZSM-12 samples with Si/Al ratio around 30 was achieved using a minimal amount of relatively inexpensive TEABr (TEA/SiO 2 =0.125). Aluminum-27 NMR spectroscopy unambiguously revealed that all aluminum atoms are incorporated in the zeolite framework in tetrahedral coordination. The NMR line-widths of aluminum signals of the calcined samples were significantly larger than those with template incorporated samples. Spin-lattice relaxation times, conventional and rotating frame, as well as magic angle spinning (MAS) cross-polarization data with variable contact time support that there is a significant proton reservoir in the aluminum framework. The NMR data indicate that many distorted tetrahedral sites are formed upon removal of the template and some of these sites contain Al–OH moieties.
Construct Validity of the Dyadic Trust Scale

Larzelere and Huston defined trust as “the extent that a person believes another person (or persons) to be benevolent and honest” (1980), p. 596) and developed a scale alleged to have excellent construct validity as well as high reliability. An independent analysis of their Dyadic Trust Scale for a sample of 79 married couples partially supports the construct validity but suggests that the scale is measuring benevolence more than honesty or trust.
Should We Venerate That Which We Cannot Love? James Madison on Constitutional Imperfection

Scholars have long pointed to James Madison’s argument for constitutional veneration in Federalist No. 49 to illustrate what they see as Madison’s fear of democratic politics and frequent constitut...
Neuroscience Applications in Marital and Family Therapy

Historically, family therapists have relied on counseling theory and the social sciences to understand the dynamics of family relationships. These sources have been helpful, but the solutions to many problems in therapy remain elusive. This article addresses the importance of a basic understanding of neuroscience in marital, couple, and family therapy training and practice. It examines the biological and physiological processes underlying emotions, memory, and neurochemistry, and emphasizes their impact on behavior. The therapeutic benefits of movement and music are also addressed. Only with a thorough understanding of the social and biological bases of behavior will family therapists and other mental health professionals be adequately prepared to assist in finding solutions to the difficult problems encountered in family therapy. Neuroscience is an indispensable source of information and should be a part of each therapist’s academic preparation, continuing education, and lifelong learning.
Models of spinal trabecular bone loss as determined by quantitative computed tomography.

Noninvasive bone densitometry techniques have significantly improved our understanding of the pattern and magnitude of bone loss over the life span. Quantitative computed tomography (QCT) is capable of selectively measuring highly labile trabecular bone in the central portion of the vertebrae. Trabecular bone mineral density (mg/ml) was determined in 538 healthy women ranging in age from 20 to 80 using GE CT/T scanners at 80 kVp. Various statistical regressions were performed for the entire population to describe the general pattern of bone loss from the spine; a cubic model (r = -0.69, SEE = 26.0 mg/ml) was found to be statistically superior (p < 0.01) to linear, quadratic, or exponential models. An average bone loss was approximated from these regression analyses with a yearly absolute rate of -2.02 ± 0.097 mg/ml per year (p < 0.0001). The average rate of change for premenopausal women was -0.45 mg/ml per year (p < 0.05), for perimenopausal women was -4.39 mg/ml per year (p < 0.0001) and for postmenopausal women was -1.99 mg/ml per year (p < 0.0001). QCT values were also stratified into 5 and 10 year age groups and analyzed seperately for pre- and postmenopausal women. The 5 and 10 year interval stratification revealed no identifiable bone density decrements prior to midlife using analysis of variance statistical methods; significant losses of bone mineral density were noted to correspond with the usual time of menopause and to continue into old age. Various two-phase regressions were employed using age and menstrual status to improve the description of age- and menopause-related bone loss. For all women, a linear-exponential pattern (r = -0.70, SEE = 25.44 mg/ml) with a decrement of 25 mg/ml across the early menopause, appeared most plausible, amounting to an average bone loss of 60% over the life span. We provide normative data here on spinal trabecular bone density appropriate for clinical comparison of female subjects encompassing the adult age range and menopausal status.
Temperature maintenance and CO2 concentration in a swarm cluster of honey bees, Apis mellifera

Abstract 1. 1. A swarm cluster of bees had a nearly constant core temperature (mean = 34.0°C) despite air temperatures that ranged from 4.0 to 16.4°C. 2. 2. Core CO2 concentrations were inversely correlated with air temperatures, suggesting that the bees regulated cluster temperature by appropriate variation of their rate of heat production. 3. 3. Contraction of the cluster to conserve heat at the lower air temperatures was not detectable.
Systematic Comparisons between Broken Symmetry and Symmetry-Adapted Approaches to Transition States by Chemical Indices: A Case Study of the Diels−Alder Reactions†

Systematic comparisons between broken symmetry (BS) and symmetry-adapted (SA) approaches to transition states were carried out using chemical indices, which are defined using the occupation numbers of natural orbitals (NOs) by both BS and SA methods. For the former, unrestricted Hartree−Fock, UMP2, UQCISD(T), and UCCSD(T), together with hybrid density functional theory (DFT) methods such as UB2LYP and UB3LYP, were employed, while CASSCF, UNO CASCI, UNO CASCI MP2 (≡ CASMP2(CI)), and MRMP2 were used for the latter approach. To begin with, we examined the functional behaviors of chemical indices during the C−C bond dissociation process of ethylene or the least motion association reaction of triplet methylenes. The bonding characteristics revealed by the chemical indices are largely dependent on the computational methods. Next, the energy difference between concerted and nonconcerted transition structures of the Diels−Alder reaction of butadiene and ethylene was calculated by both BS and SA methods. The origi...
Optimal Germinal Center Responses Require a Multistage T Cell:B Cell Adhesion Process Involving Integrins, SLAM-Associated Protein, and CD84

Summary CD4 + T cells deficient in signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) exhibit a selective impairment in adhesion to antigen-presenting B cells but not dendritic cells (DCs), resulting in defective germinal center formation. However, the nature of this selective adhesion defect remained unclear. We found that whereas T cell:DC interactions were primarily integrin dependent, T cell:B cell interactions had both an early integrin-dependent phase and a sustained phase that also required SAP. We further found that the SLAM family member CD84 was required for prolonged T cell:B cell contact, optimal T follicular helper function, and germinal center formation in vivo. Moreover, both CD84 and another SLAM member, Ly108, mediated T cell adhesion and participated in stable T cell:B cell interactions in vitro. Our results reveal insight into the dynamic regulation of T cell:B cell interactions and identify SLAM family members as critical components of sustained T cell:B cell adhesion required for productive humoral immunity.
Distance Students' Attitude Toward Library Help Seeking

Abstract Distance students' attitude toward seeking library help was examined in a medium sized university. A web-based survey was conducted for indentifying library help seeking attitudes among distance students. A 30-mile radius of the campus was used to arbitrarily distinguish between near campus and far campus groups. The study concluded that distance students who visit library and seek help more frequently are more likely have higher self-efficacy on learning. Among all types of library help sources, Libguides were the most used. Near campus students preferred face-to-face consultation more than virtual service, and they also tend to seek help from peers. However, far campus students were more likely seek help with a distance librarian. Email continued to be the most common way of distributing and receiving library information. Social network tools for information seeking were not appreciated as had been anticipated. Implications of the findings for providing effective reference service are discussed. There is not one reference service model that fits all. A library should determine the best reference service that meets the changes of their communities and library's function over time.
Principles of drug therapy in child psychiatry with special reference to stimulant drugs.

Drugs promise neither the passport to a brave new world nor the gateway to the inferno. Properly employed as a single component of a total treatment program, they can be helpful in realizing the goal of the healthy development of children. Four problem areas are discussed, and principles for the use of stimulant drugs with children are proposed.
Transitions in morphology observed in nitrogen/methane-hydrogen depositions of polycrystalline diamond films

In this work, we report on a series of transitions in morphology and texture as 5–1000 parts per million of nitrogen were added to 2% and 1% methane–hydrogen depositions of polycrystalline diamond films. Five results are reported. (1) The threshold for transition into the {100}-faceted morphology occurred at lower parts per million nitrogen for the 1% versus the 2% methane–hydrogen series, opposite from the transition thresholds previously reported. (2) At 1000 parts per million nitrogen the film quality of both series had not yet seriously degraded. (3) A well defined sequence of intermediate texture transitions as a function of increasing parts per million nitrogen was observed for both series. (4) A pretransition morphology of large crystallites interspersed among microcrystalline material directly preceding the transitions to the {100}-faceted morphology was observed for both series. (5) A layered growth and/or etched morphology at high nitrogen concentrations was observed for both series. We discuss ...
Verbal memory deficits associated with major affective disorders: a comparison of unipolar and bipolar patients.

The verbal learning and fluency of patients with unipolar and bipolar depression were compared to those of normal controls and patients with Huntington's disease. The data demonstrated that the recall and recognition performance of both groups of depressed patients were imparred relative to the performance of normal control subjects. The bipolar patients, however, were more impaired than the unipolar patients on both tasks (P<0.024 and P<0.022, respectively). In addition, the unipolar patients generated more correct responses on a test of verbal fluency (P<0.04). The performance of the bipolar patients was, in fact, similar to that of patients with Huntington's disease, a progressive degenerative disorder that primarily affects subcortical areas.
Ephrin regulation of synapse formation, function and plasticity

Synapses enable the transmission of information within neural circuits and allow the brain to change in response to experience. During the last decade numerous proteins that can induce synapse formation have been identified. Many of these synaptic inducers rely on trans-synaptic cell–cell interactions to generate functional contacts. Moreover, evidence now suggests that the same proteins that function early in development to regulate synapse formation may help to maintain and/or regulate the function and plasticity of mature synapses. One set of receptors and ligands that appear to impact both the development and the mature function of synapses are Eph receptors (erythropoietin-producing human hepatocellular carcinoma cell line) and their surface associated ligands, ephrins (Eph family receptor interacting proteins). Ephs can initiate new synaptic contacts, recruit and stabilize glutamate receptors at nascent synapses and regulate dendritic spine morphology. Recent evidence demonstrates that ephrin ligands also play major roles at synapses. Activation of ephrins by Eph receptors can induce synapse formation and spine morphogenesis, whereas in the mature nervous system ephrin signaling modulates synaptic function and long-term changes in synaptic strength. In this review we will summarize the recent progress in understanding the role of ephrins in presynaptic and postsynaptic differentiation, and synapse development, function and plasticity.
Embedded mesh solution of the 2-D Euler equations - Evaluation of interface formulations

Solution of the steady 2-D Euler equations using mesh embedding, or local grid refinement, with a cell-centered finite volume scheme is investigated. Embedded regions which are topologically similar to the global grid are considered. An isoenergetic model for the governing equations is used in Jameson's finite volume multistage scheme with modifications to the boundary conditions and smoothing. A detailed study of the embedding interface flux and smoothing formulations is conducted. Taylor expansion analysis reveals that local second order spatial accuracy is not possible if a conservative interface flux formulation is used. The analysis also gives constraints for local first order accuracy. An energy stability analysis indicates that downwind weighting of interface fluxes causes local instabilities. Analysis shows that conservative interface smoothing formulations must have a locally convective component, but that correct interface formulations allow globally dissipative smoothing. Embedded mesh solutions obtained with this scheme are presented for a transonic airfoil. They show that if embedding interfaces are close to the shocks, then small modifications in the interface location can have large effects on converge and solution accuracy.