cssi/SciSciGPT-SciSciNet huggingface dataset:
The ATP Hydrolytic Activity of Purified ZntA, a Pb(II)/Cd(II)/Zn(II)-translocating ATPase from Escherichia coli

ZntA, a soft metal-translocating P1-type ATPase from Escherichia coli, confers resistance to Pb(II), Cd(II), and Zn(II). ZntA was expressed as a histidyl-tagged protein, solubilized from membranes with Triton X-100, and purified to homogeneity. The soft metal-dependent ATP hydrolysis activity of purified ZntA was characterized. The activity was specific for Pb(II), Cd(II), Zn(II), and Hg(II), with the highest activity obtained when the metals were present as thiolate complexes of cysteine or glutathione. The maximal ATPase activity of ZntA was ∼3 μmol/(mg·min) obtained with the Pb(II)-thiolate complex. In the absence of thiolates, Cd(II) inhibits ZntA above pH 6, whereas the Cd(II)-thiolate complexes stimulate activity, suggesting that a metal-thiolate complex is the true substrate in vivo. These results are consistent with the physiological role of ZntA as mediator of resistance to toxic concentrations of the divalent soft metals, Pb(II), Cd(II), and Zn(II), by ATP-dependent efflux. Our results confirm that ZntA is the first Pb(II)-dependent ATPase discovered to date.
SLIP BOUNDARY CONDITION FOR VISCOUS FLOW OVER SOLID SURFACES

A slip boundary condition is derived for the flow of a viscous fluid over a solid surface, using the theory of thermal activation process. The slip velocity is proportional to the hyperbolic sine of the shear stress on the solid surface, and the slip boundary condition reduces to Navier's slip boundary condition for the flow of Newtonian fluids under small shear stresses. There exists a critical shear stress determining the onset of the slip flow.
Biosynthesis of Lycosantalonol, a cis-Prenyl Derived Diterpenoid

Terpenoid natural products are generally derived from isoprenyl diphosphate precursors with trans double-bond configuration, and no diterpenoid derived from the cisoid precursor (Z,Z,Z)-nerylneryl diphosphate (1) has yet been identified. Here further investigation of a terpenoid biosynthetic gene cluster from tomato is reported, which resulted in identification of a biosynthetic pathway from 1, in a pathway featuring a number of interesting transformations. Compound 1 is first cyclized to a tricyclene core ring structure analogous to that found in α-santalene, with the resulting diterpene termed here lycosantalene (2). Quantum chemical calculations indicate a role for the diphosphate anion coproduct in this cyclization reaction. Subsequently, the internal cis double bond of the neryl side chain in 2 is then further transformed to an α-hydroxy ketone moiety via an epoxide intermediate (3). Oxygen labeling studies indicate 3 undergoes oxidative conversion to lycosantalonol (4). Thus, in addition to elucidat...
Practicality of compensating the loss in the plasmonic waveguides using semiconductor gain medium

We consider the issue of compensating the loss in plasmonic waveguides with semiconductor gain material and show that, independent of specific geometry, full loss compensation in plasmonic waveguides with significantly sub-wavelength light confinement (less than λ/4n) requires current density well in excess of 100 kA/cm2. This high current density is attributed to the unavoidable shortening of recombination time caused by the Purcell effect inherent to sub-wavelength confinement. Consequently, an injection-pumped plasmonic laser that is truly sub-wavelength in all three dimensions (“spaser”) would have threshold current densities that are hard to obtain in any conceivable semiconductor device.
Signaling regulation of genomic and nongenomic functions of estrogen receptors

Abstract Estrogen receptors (ERs) mediate the effects of 17β-estradiol under physiologic and pathologic conditions. ERs trigger 17β-estradiol-sensitive gene transcription by binding to specific estrogen response elements (i.e. genomic mechanism). The cellular effects of estrogen are also influenced by membrane- or cytoplasm-initiated responses (i.e. nongenomic mechanism). Both ER-evoked genomic and nongenomic effects originate from a unique signaling network. Furthermore, estrogen-initiated rapid pathways and ERα interactions with specific partners (e.g. AIB1, PELP1/MNAR; MTA1, MTA1s and p130Cas) influence both ER functions. Here, we summarize the recent findings related to multiple regulatory levels of the signaling networks responsible for ERs-mediated responses in breast cancer cells.
The Mitochondrial Spiral: An Adequate Cause of Dementia in the Alzheimer's Syndrome

: A variety of chronic, relatively low-grade injuries to the brain occur in Alzheimer's disease (AD). The extent to which each of these contributes to the clinical syndrome is unclear. Several of the abnormalities that occur in AD brain can cause dementia by themselves, even in people who do not have the neuropathological hallmarks of AD. Prominent among these abnormalities is a deleterious “mitochondrial spiral,” which consists of reduced brain metabolism, oxidative stress, and calcium dysregulation. The hypothesis presented in this paper is that the mitochondrial spiral contributes to dementia in AD and presents a reasonable target for the development of new approaches to the treatment of this syndrome.
Provider adherence to COPD guidelines: relationship to organizational factors

Rationale, aims and objectives A clinical practice guideline for chronic obstructive pulmonary disease (COPD) was implemented in all Veterans Health Administration (VHA) hospitals in the US. The aim of the current analyses is to describe current adherence rates and the organizational factors related to provider adherence to the COPD guideline. Methods We administered a survey to key informants that assessed adherence to the COPD guideline, approaches to disseminating and implementing the COPD guideline, providers’ views of the COPD guideline and guidelines in general, and attitudes about the organizational climate. Results Surveys were returned by 242 key informants (58%) at 130 of the 143 VHA hospitals (91%). Adherence to the COPD clinical practice guideline is perceived by quality managers within the VHA to be good. The final multivariable predictor model identified five measures that were related to provider adherence with the COPD guideline (R 2 = 0.43): responsibilities were changed to support adherence to the COPD guideline, physicians believe that guidelines implemented in the past year were applicable to their practice, patient care providers consistently participate in activities to improve the quality of care, the regional network office monitors the pace at which guidelines are implemented, and there is a system to provide feedback on routinely collected guideline adherence data collected in addition to External Peer Review Program data. Conclusions Organizations can play an important role in providing a supportive climate to facilitate their providers’ adherence to guidelines by implementing processes and culture changes that involve these five measures.
Biopolymers from Vegetable Oils via Catalyst- and Solvent-Free "Click" Chemistry: Effects of Cross-Linking Density

New monomers were prepared by introducing the azide groups in castor, canola, corn, soybean, and linseed oils. Polymerization of the azidated oils with alkynated soybean oil under thermal “click” chemistry conditions (without using a solvent or a catalyst) yielded fully cross-linked elastomers (1–5) of almost the same density (1.05 × 10–3 kg/m3). The degree of cross-linking gradually increased from the castor-derived polymer (220 mol/m3) to the linseed-derived polymer (683 mol/m3). A systematic correlation between the degree of cross-linking and the thermal and mechanical properties was observed in these biopolymers. Tensile strength (0.62–3.39 MPa) and glass transition temperature (−5 to 16 °C) increased and the linear thermal expansion coefficient decreased in the series from the canola-derived polymer (2) to the linseed-derived polymer (5). The castor-derived polymer (1) that possesses an additional hydroxyl group per fatty acid chain behaved differently.
Stripping voltammetry of manganese based on chelate adsorption at the hanging mercury drop electrode

Abstract A novel electrochemical stripping approach for the trace measurement of manganese is presented. The metal chelate with erichrome black T is adsorbed on a hanging mercury drop electrode, and the subsequent reduction current of the accumulated chelate is measured by voltammetry. Adsorptive preconcentration for 5 min results in a detection limit of 6 × 10−10 M (32 l−1). Cyclic voltammetry is used to characterize the redox and interfacial processes. Optimal experimental conditions include a 0.02 M piperazine-N,N′-bis(2-ethanesulfonic acid) solution (pH 12) containing 1 × 10−6 M eriochrome black T, a preconcentration potential of −0.80 V, and a linear potential scan. The response is linear up to 2.9 × 10−7 M, and the relative standard deviation at 1.8 × 10−7 M is 1.5%. The effects of possible interferences from metal ions or organic surfactants are evaluated.
Antibodies Mimic Natural Oxidosqualene−Cyclase Action in Steroid Ring A Formation

Cationic cyclizations are among the most demanding reactions that have been catalyzed by antibodies. These studies provided valuable mechanistic insights while opening up the possibility of formation of steroidal carbon frameworks. However, they have involved substrates that contained an aryl sulfonate group adjacent to a primary carbon center not observed in natural cationic cyclization processes. This paper presents an extension of our earlier work, now focusing on substrates analogous to those seen in triterpene biosynthesis. Three antibodies, 15D6, 20C7, and 25A10, have been generated by immunization with an 4-aza-steroid aminoxide hapten (termed HA8) that initiate the cationic cyclization of an oxidosqualene derivative and catalyze the formation of ring A of the lanosterol nucleus at neutral pH. Antibody HA8-25A10 kinetically resolved its racemic substrates. Design of the substrate was based on a dual-anchor model for specific binding that consists of displaying a functional group at the head (epoxid...
Deep overbite correction by intrusion

Abstract Not all patients with deep overbite should be treated with the same mechanics. Some patients require intrusion of the anterior teeth, while others require primarily extrusion. This article has discussed the principles of incisor and canine intrusion and has demonstrated the use of intrusion springs that are capable of intruding incisors with minimal side effects on the posterior teeth. Six principles must be considered in incisor or canine intrusion: (1) the use of optimal magnitudes of force and the delivery of this force constantly with low-load-deflection springs; (2) the use of a single point contact in the anterior region; (3) the careful selection of the point of force application with respect to the center of resistance of the teeth to be intruded; (4) selective intrusion based on anterior tooth geometry; (5) control over the reactive units by formation of a posterior anchorage unit; and (6) inhibition of eruption of the posterior teeth and avoidance of undesirable eruptive mechanics.
Chloride transport and its inhibition by thiocyanate in gills of seawater teleosts.

Abstract 1. Intraperitoneal injections of sodium thiocyanate (0·14 to 0·20 mM per 100 g body wt) reduced chloride efflux across the gill by about 50% in seawater specimens of Anguilla rostrata and Pseudopleuronectes americanus. In Fundulus heteroclitus adapted to seawater, however, no inhibitory effect of thiocyanate could be detected. 2. Neither sodium perchlorate nor sodium iodide inhibited chloride efflux in Anguilla rostrata. Phloretin injected intravenously in Pseudopleuronectes americanus was likewise without effect on chloride flux. 3. Tracer quantities of 35SCN are accumulated against an electrochemical gradient by freshwater Anguilla rostrata and extruded against an electrochemical gradient by saltwater fish, suggesting that thiocyanate is transported by a mechanism similar or identical to that responsible for the active transport of chloride by teleost gills.
Auditory discrimination and the eyeblink.

This experiment evaluated the association between blinking and cognitive activities. Subjects received 200 and 400 ms tones (1 KHz) at fixed intervals in a duration discrimination paradigm. One group (“Task”) was instructed to respond to the stimuli on the basis of duration and another (“No-Task”) was instructed to ignore the stimuli. Blink activity (latency, rate, duration) and performance (RT, hit and false alarm rates) measures were evaluated. A first analysis (Task subjects only) indicated that stimulus duration had significant effects on RT and blink latency; both were generally longer following the 400-ms than the 200-ms stimuli. In a second analysis, involving Task and No-Task subjects, blink latencies were shorter in the Task group. Blink and eyelid closure durations increased over the task period in both analyses. These effects suggest that blinks occur when attentional processes wane.
Generalized dynamic reduction in finite element dynamic optimization

On effectue une reconception automatisee des systemes structuraux non amortis pour des changements de frequences. La methode met en jeu une perturbation non lineaire a partir de la conception de base. Des coordonnees generalisees sont introduites pour transformer le probleme original dans un sous-espace de petite taille. Un schema de programmation mathematique non lineaire est applique dans le sous-espace reduit
A Species Cytoplasm Specific gene in euplasmic durum wheat does not alter field performance

Wild related Triticum species have been and will be a useful reservoir of genetic diversity for solving problems in the development of improved durum (Triticum turgidum L. var. durum) and bread wheat (T. aestivum L.) cultivars. The alien germplasm may be used to reduce vulnerability of cultivars to pests, and improve agronomic fitness and grain quality. However, lack of genetic recombination and hybrid sterility are two obstacles to the use of alien germplasms. Nuclear-cytoplasmic (NC) incompatibility is known to exist between the T. longissimum S. & M. cytoplasm and T. turgidum nucleus. A two-gene system has been found that restores fertility in this situation: the species cytoplasm specific (scs) gene and the vitality (Vi) gene. This gene system can also be used for the production of hybrid wheat. Effects of these genes on euplasmic (true cytoplasm) durum wheat under a field environment had not been previously investigated. In this study, lines with two copies of the scs(ti) gene, derived from T. timopheevii Zhuk., were compared to lines without the copy of the gene, the parents, and four durum cultivars for five agronomic characteristics: days to heading, plant height, lodging resistance, grain yield, and kernel test weight. Comparison of genotypes homozygous for the scs(ti) gene and those containing no scs(ti) gene indicated minor differences among them, confirming that the scs(ti) gene does not confer any detrimental effects in the euplasmic situation. Thus, the scs(ti) gene could be useful in the production of hybrids in durum wheat.
Apoptotic-like morphology is associated with annual synchronized death in kleptoplastic sea slugs (Elysia chlorotica)

Abstract. Certain digestive cells of the opisthobranch mollusc, Elysia chlorotica, contain functional chloroplasts which they steal from the filamentous alga, Vaucheria litorea. The adult portion of the life cycle of the slug lasts for ∼10 months and is completely synchronized among individuals. All the adults die each year within a few weeks of each other. We have examined the microscopic morphology of the slugs near the end of the life cycle. Light microscopy demonstrated an absence of chloroplasts in most of the digestive epithelial cells, the appearance of many crypt cells containing residual bodies and an invasion of the blood sinuses by neoplastic morula-like cells as the animals die. Electron microscopy revealed a degeneration of the digestive diverticulum which had several morphological characteristics in common with apoptosis: expansion of the endoplasmic reticulum and Golgi apparatus, DNA fragmentation, formation of primary lysosomes, and condensation of chromatin. These are followed by fragmentation of the nucleus and cytoplasm into autosomes merging to form a large central autolysosome. In addition in the aging slugs, the plastids begin to degenerate until none were left in the digestive epithelial cells and the central autolysosome contained numerous viral particles.
The role of nitric oxide in the pathogenesis of preeclampsia

Abstract Objective: Nitric oxide, a potent vasodilator released by endothelial cells, inhibits platelet aggregation and adhesion to vascular endothelial surfaces. Because endothelial cell damage is considered pivotal in the pathogenesis of preeclampsia, this study was initiated to determine whether nitric oxide production is decreased in patients with preeclampsia. Study Design: Twenty-six patients with preeclampsia (as defined by a blood pressure ≥ 140 mm Hg systolic or 90 mm Hg diastolic plus proteinuria, ≥ 300 mg per 24 hours or ≥ 2 + by dipstick, both occurring on two occasions ≥ 4 hours apart) and 26 normotensive women with singleton gestations in the third trimester were studied. Because nitric oxide is spontaneously oxidized to both nitrite and nitrate, two analytic assays were used serially. Serum nitrite levels were initially determined with the Greiss reagent and subsequently analyzed with Escherichia coli nitrate reductase. Results: With the Greiss reagent alone the mean ± SEM of serum nitrite level in 26 patients with preeclampsia was significantly decreased compared with 26 normotensive patients (3.46 ± 1.43 μmol/L vs 4.65 ± 0.85 μmol/L, p = 0.02). With the addition of the nitrate reductase enzyme of Escherichia coli the mean ± SEM of serum nitrite level in 26 preeclamptic patients was again significantly decreased compared with 26 normotensive patients (20.04 ± 1.25 μmol/L vs 27.38 ± 2.23 μmol/L, p = 0.02). One patient with the syndrome of hemolysis, elevated liver enzymes, and low platelets demonstrated a concurrent decrease in serum nitrite over a 2-week period, emphasizing the relationship of nitric oxide to the pathophysiologic features of the syndrome. Conclusions: Circulating levels of nitrite are decreased in patients with preeclampsia. These data support the concept that diminished nitric oxide synthesis contributes to the pathophysiologic changes seen in preeclampsia.
The biology of osteoarthritis.

OSTEOARTHRITIS, "an almost inevitable consequence of aging,"1 is second only to cardiovascular diseases in producing severe chronic disability, and it affects nearly 10 percent of the population ov...
Psychopharmacoepidemiology of mental retardation: 1966 to 1995.

ABSTRACT We present a brief historical overview of the prevalence studies of psychotropic drugs in individuals with mental retardation that were published between 1966 and 1985, and a more comprehensive review of the prevalence studies from 1986 to 1995. During the 1966 to 1985 period, typical prevalence rates of drug treatments in institutions (children and adults analyzed together) were found to range from 30% to 40% for psychotropic drugs, 25% to 45% for anticonvulsants, and 50% to 70% for psychotropic and/or anticonvulsant drugs (i.e., psychotropics, anticonvulsants, or their combinations). In the community during the same period, prevalence rates in children were typically 2% to 7% for psychotropics, 12% to 31% for anticonsulvants, and 18% to 33% for psychotropic and/or anticonvulsant drugs. For adults in the community, prevalence rates ranged from 26% to 36% for psychotropics, 18% to 24% for anticonvulsants, and 36% to 48% for psychotropic and/or anticonvulsant drugs. In contrast, during the 1986 to...
Prevalence of renal cell carcinoma in patients with ESRD pre-transplantation: A pathologic analysis

Prevalence of renal cell carcinoma in patients with ESRD pre-transplantation: A pathologic analysis . Background Acquired renal cystic disease (ARCD), renal adenoma (AD), and renal cell carcinoma (RCC) are more common in patients with end-stage renal disease (ESRD). However, the prevalence of these conditions in patients undergoing transplantation, and the clinical characteristics associated with their occurrence are unclear. Methods At our institution, the majority of patients undergo an ipsilateral native nephrectomy at the time of transplantation, providing a unique opportunity to study the prevalence and pathology of ARCD, AD and RCC in ESRD. We retrospectively reviewed all consecutive nephrectomy pathology reports over a six year period. Demographic and clinical characteristics associated with these lesions were identified. Results Two hundred and sixty nephrectomy reports were reviewed: ARCD, AD, RCC and oncocytoma were found in 33%, 14%, 4.2% and 0.6% of cases, respectively. On multivariable analysis, ARCD was positively associated with male sex and longer dialysis duration and negatively associated with peritoneal dialysis. Similarly, AD was positively associated with male sex, longer dialysis duration and greater age. There was a trend for RCC cases to share similar associations although the small total number of cases precluded findings of statistical significance. Conclusion By pathologic analysis, renal tumors are more common in the pre-transplant ESRD population than previously reported (using radiologic methods). Our study also identifies risk factors for their occurrence. This may prove useful in designing screening studies for renal tumors in this patient population.
Development and mortality of Ips calligraphus (Coleoptera: Scolytidae) at constant temperatures.

We describe effects of constant temperature, beetle density, and time of oviposition on aspects of development, mortality, sex ratio, and size of Ips calligraphus (Germar). Emphasis is placed on individual life stages. Relationships of median development times to constant temperatures were similar for eggs, larvae, and pupae in the 12.5–37.5°C range. These relationships appeared as backward J-shaped curves. Reciprocal development times versus temperatures for these life stages were described by the six-parameter rate function of Sharpe & DeMichele (1977, J. Theor. Biol. 64: 649–670). Development times and foraging distances of larvae increased with each instar. The third instar required 61% of total larval time and excavated 73% of the total larval gallery. Optimum development temperature of teneral adults was not identified, indicating greater tolerance to high temperatures of this stage compared with the others. The four-parameter Sharpe & DeMichele (1977) model (without high-temperature inhibition) described teneral adult rate as a function of temperature. Timing of oviposition influenced development time of larvae (increased development time with late oviposition) and teneral adults (decreased), but not development times of eggs or pupae. Reversed patterns of longer development times for larvae and shorter times for teneral adults canceled any effects of sequential oviposition on length of life cycle. Distributions of development times were generally skewed toward the longer times, and variation around mean time tended to increase with successive life stage. A single, temperature-independent distribution of normalized development times is presented for each life stage and is described by a three-parameter cumulative Weibull function. Stage-specific mortality (resulting from unknown causes) formed partial or full U-shaped patterns when plotted against temperature. Density-dependent mortality resulting from cannibalism is discussed, with a Weibull function describing influence of egg density on probability of being cannibalized. Timing of oviposition influenced percentage of mortality of all life stages, primarily due to increased cannibalism of later-developing brood. An overall sex ratio of 1:1 was observed, but proportion of males to total I. calligraphus increased from 0.374 in the first quarter of the emergence period to 0.569 in the fourth quarter. Beetles reared at 15–25°C were somewhat larger than those reared at 30–35°C. Generally, males were slightly larger than females when size was examined relative to time of emergence. An inverse relationship of beetle size to time of emergence was observed for each sex.
Latency of EEG attenuation ("blocking") in relation to age and reaction time in normal children.

Blocking latency of the EEG (BL) and reaction time (RT) were investigated in 53 normal boys aged 88–207 months. The purpose was to discover whether changes in BL which have been reported to occur during growth in children parallel the well known decrease in RT that accompanies development. EEGs were recorded (1) during an experiment in which the tracings were attenuated by short, high intensity flashes of white light, and, (2) while the subjects performed an auditory reaction task in which they responded to a tone that occurred without warning by closing a switch as quickly as possible. As expected, findings showed an inverse relationship between RT and age of substantial magnitude (r= −.822). By contrast, no relationship was apparent between BL and age in the group tested. This finding, together with the fact that the correlation between BL and RT was not significantly different from zero, suggested that BL and RT follow different developmental courses and may be measures of essentially independent systems in children 7 years and older.
The chief resident in psychiatry: roles and responsibilities.

Objective Psychiatric residency programs have had chief residents for many years, and several articles previously published describe the chief residents’ unique role as both faculty and resident. This article describes chief resident roles and responsibilities and explores trends in academic psychiatry departments from 1995 to 2006.
Influence of Therapeutic Hypothermia on Matrix Metalloproteinase Activity after Traumatic Brain Injury in Rats

Recent evidence suggests that matrix metalloproteinases (MMPs) contribute to acute edema and lesion formation following ischemic and traumatic brain injuries (TBI). Experimental and clinical studies have also reported the beneficial effects of posttraumatic hypothermia on histopathological and behavioral outcome. The purpose of this study was to determine whether therapeutic hypothermia would affect the activity of MMPs after TBI. Male Sprague-Dawley rats were traumatized by moderate parasagittal fluid-percussion (F-P) brain injury. Seven groups (n = 5/group) of animals were investigated: sham-operated, TBI with normothermia (37°C), and TBI with hypothermia (33°C). Normothermia animals were killed at 4, 24, 72 h and 5 days, and hypothermia animals at 24 or 72 h. Brain temperature was reduced to target temperature 30 mins after trauma and maintained for 4 h. Ipsilateral and contralateral cortical, hippocampal, and thalamic regions were analyzed by gelatin and in situ zymography. In traumatized normothermic...
PERCEIVED DEPTH FROM SIMULTANEOUS CHANGES IN LENGTH AND DIRECTION OF A SINGLE LINE

Using a configuration of three lines joined like hands on a clockface, Brigner, Deni, and Hildreth in 1994 reported empirical support for Wallach, Adams, and Weisz's 1956 hypothesis regarding the elicitation of perceived depth by simultaneous changes in length and orientation of a configuration's elements. The current investigation extended these findings by showing that perceived depth can be elicited by simultaneous changes in size and orientation of either two lines or a single line.
Influence of Input Motion and Site Property Variabilities on Seismic Site Response Analysis

Seismic site response analysis evaluates the influence of local soil conditions on earthquake ground shaking. There are multiple sources of potential uncertainty in this analysis; the most significant pertaining to the specification of the input motions and to the characterization of the soil properties. The influence of the selection of input ground motions on equivalent-linear site response analysis is evaluated through analyses performed with multiple suites of input motions selected to fit the same target acceleration response spectrum. The results indicate that a stable median surface response spectrum (i.e., within ±20% of any other suite) can be obtained with as few as five motions, if the motions fit the input target spectrum well. The stability of the median is improved to ±5 to 10% when 10 or 20 input motions are used. If the standard deviation of the surface response spectra is required, at least 10 motions (and preferably 20) are required to adequately model the standard deviation. The influence of soil characterization uncertainty is assessed through Monte Carlo simulations, where variations in the shear-wave velocity profile and nonlinear soil properties are considered. Modeling shear-wave velocity variability generally reduces the predicted median surface motions and amplification factors, most significantly at periods less than the site period. Modeling the variability in nonlinear properties has a similar, although slightly smaller, effect. Finally, including the variability in soil properties significantly increases the standard deviation of the amplification factors but has a lesser effect on the standard deviation of the surface motions.
Electromagnetic modeling of multi-wavelength QWIP optical coupling structures

Quantum-well infrared photodetector (QWIP) materials can be engineered to be optically absorbing over a wide range of wavelengths. This enables multi-band focal plane arrays to be realized. However, some of this flexibility is lost due to the required optical coupling structure that converts normally incident light to horizontal propagation to allow absorption. Such coupling structures are typically strongly wavelength-dependent and must be tuned to the waveband of interest. In this study, we perform electromagnetic simulations to understand and optimize optical coupling structures for multi-band QWIPs.
Computer models of language acquisition

Abstract Since the method of computer simulation was introduced to the study of human behavior, a number of computer models of language acquisition have been proposed and implemented on a computer system. Because of varied purposes of simulation and diverse theoretical backgrounds of the model builders, there are notable dissimilarities among the models. This paper reviews the existing computer models of language acquisition. The comparison is done in terms of the basic components of the models: (a) input to the computer system, (b) how linguistic knowledge and the process of learning are represented, and (c) what is initially built into the system and what is learned. Based on the review, the potential usefulness of the computer simulation methods in the area of child language is dicussed.
Synthesis of time-varying bandwidth filters based on all-pole LTI prototypes

This paper presents a systematic procedure for synthesizing a class of time-varying bandwidth (TVB) filter using a parallel D-eigenvalue concept and a stability criterion for linear time varying (LTV) systems. Time-varying frequency response of the TVB filter is analyzed and a computable procedure is used to obtain "time-varying Bode plots". Comparisons are made with LTI filters with or without limiter to demonstrate the advantages of the TVB filter. While the procedure is presented for nth-order single-input-single-out lowpass filters based on all-pole LTI prototypes, extension of the results to more general cases are addressed. Application for tracking command shaping filters, implementation of pseudo-differentiators, pseudo-inverse of nonlinear dynamics and nonlinear asymptotic state observers are also discussed.
The relationship between shape under similarity transformations and shape under affine transformations

Recent progress in shape theory, including the development of object/image equations for shape matching and shape space metrics (especially object/image metrics), is now being exploited to develop new algorithms for target recognition. This theory makes use of advanced mathematical techniques from algebraic and differential geometry to construct generalized shape spaces for various projection and sensor models, and then uses that construction to find natural metrics that express the distance (difference) between two configurations of object features, two configurations of image features, or an object and an image pair. Such metrics produce the most robust tests for target identification; at least as far as target geometry is concerned. Moreover, they also provide the basis for efficient hashing schemes to do target identification quickly and provide a rigorous foundation for error analysis in ATR.
Monte Carlo simulations of very low pressure chemical vapor deposition

Simulation strategies for chemical vapor deposition (CVD) of thin solid films are presented, with emphasis on direct simulation Monte Carlo methods for analyzing and predicting physical phenomena occurring at low pressures and in micron-sized substrate features. The Monte Carlo approach is placed in perspective, relative to standard continuum mechanics-based strategies for modeling of CVD systems. Design issues that may be addressed through the developed methods are exemplified with computations for a new, technologically important CVD process for epitaxy of Si and SixGe1-x alloys. Specifically, radiative heat transfer, rarefied gas-flow characteristics, species separation caused by pressure and thermal diffusion, growth-rate uniformity vs. surface reactivity, and deposition in microscopic features are addressed as parts of the overall CVD reactor-design approach. Process implications of rarefied transport effects unique to very low pressure CVD conditions are described. A new profile evolution technique is also introduced which predicts film topology, as well as the microstructure of the film.
Magnetic circular dichroism studies of Mn[Mn(CN)6]

Abstract A magnetic circular dichroism (MCD) study of the Prussian Blue analogue, Mn[Mn(CN) 6 ], has been undertaken in order to investigate further the magnetic and optical properties of this material and determine the feasibility of MCD spectroscopy for the study of magnetically ordered solids. The temperature-dependent MCD magnetization behavior is consistent with ferrimagnetic long-range order below a Curie temperature of 4 K. Numerous bands have been assigned in the MCD spectrum, and the study indicates that the MCD technique is an excellent tool for determining the relationship between molecular level electronic structure and the magnetic properties of the bulk material.
Identification of calbindin D-9k mRNA and its regulation by 1,25-dihydroxyvitamin D3 in Caco-2 cells.

Abstract We have identified and quantified specific mRNAs in the human colonic carcinoma cell line Caco-2 by reverse transcriptase-polymerase chain reaction. Initial examination revealed that like rat duodenal mucosa, Caco-2 cells possessed mRNA for the vitamin D receptor. Using primers for human calbindin we found a 237-bp PCR product in Caco-2 cell RNA, but not from rat duodenal RNA. Primers for rat calbindin did not amplify calbindin mRNA in Caco-2 RNA, confirming a high degree of mismatch between rat and human sequences. 1 ,25(OH) 2 vitamin D 3 treatment (10 nM) significantly elevated calbindin mRNA levels 50% by 12 h, with maximal levels occurring by 48 h (fivefold elevation). Increasing concentrations of 1,25(OH) 2 vitamin D 3 (from 15 pM to 100 nM) caused progressive increases in calbindin mRNA levels following 48 h of treatment. Elevated calbindin mRNA levels were associated with enhancement of transcellular calcium transport. Our results are the first demonstration of vitamin D-regulated calbindin mRNA in a human intestinal cell line.
Enhancement of carboplatin toxicity by Pluronic block copolymers

Abstract The objective of this study was to examine the effects of three Pluronic triblock copolymers (F127, P85, or L61) on the cytotoxicity of carboplatin to the DHB/K12/TRb rat colorectal carcinoma cell line. Studies to determine the dependence of the sensitization effect on Pluronic dose were carried out for polymer concentrations ranging from 0.0001–10% (w/w). To establish the carboplatin toxicity and its potential enhancement by Pluronic, the drug was delivered to cells in doses ranging from 0–0.5% (w/w) in the presence of Pluronic at a constant concentration. These treatment groups were compared to control groups receiving carboplatin alone. Cell cytotoxicity resulting from the treatments was determined with a mitochondrial enzyme activity assay (WST-1), while cell morphology was examined with May–Grunwald and Giemsa staining. Results indicate that the greatest enhancement of carboplatin toxicity was induced by P85, where the inhibitory concentration (IC 50 ) was reduced by 50% (from 0.096 mg/mL for carboplatin alone to 0.048 mg/mL in presence of P85). L61 was toxic to the cells with or without drug (viability
Effects of Single and Repeated Footshock on Dopamine Release and Metabolism in the Brains of Fischer Rats

Changes in the tissue levels of 3-methoxytyramine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and dopamine in the frontal cortex, hypothalamus, nucleus accumbens, and striatum were evaluated after 0.5-4 h of footshock (2 mA, for 3 s every 30 +/- 5 s) in Fischer rats. 3-MT, DOPAC, and HVA levels in the four brain areas peaked at 0.5 h and in most cases returned to baseline values within 4 h. No changes were found in dopamine levels. Repeated footshock stress was evaluated by administering 10 footshock sessions (0.5 h, two per day for 5 days). At the end of the 10th footshock session, 3-MT levels were higher than at the end of the first footshock session in three of the four brain regions, indicating sensitization of dopamine release. No differences were found between the first and 10th footshock sessions in DOPAC and HVA levels. Fourteen days after the 10th footshock session, the levels of 3-MT, DOPAC, and HVA were the same as in control rats in all four brain regions. A 0.5-h footshock challenge presented 14 days after the 10th footshock session attenuated DOPAC levels in the hypothalamus and nucleus accumbens. In contrast, DOPAC and HVA levels in the frontal cortex showed sensitization after footshock challenge, and a similar trend was apparent for 3-MT levels. These results indicate that repeated footshock stress induces generalized sensitization of dopamine release and turnover in some areas of the brain of Fischer rats. This sensitization may persist in the cortical but not subcortical dopamine neurons after discontinuation of the treatment.
Internet activism: NGOs and the Mine Ban Treaty

When the 1997 Nobel Peace Prize was awarded to the International Campaign to Ban Landmines international awareness was heightened about the efforts of NGOs worldwide to ban landmines. The international Mine Ban Treaty was signed on March 1, 1999 after serious use of the Internet to communicate how critical this was to global safety. The methods of sharing information between foreign governments and being able to track this critical communication is central to understanding how the treaty gained visibility and how NGOs created coalitions to assure the success of this work. This article talks about global communications and sharing that could not have taken place with speed, worldwide coverage, efficiency and cost‐effectiveness, if the Internet had not been born.
Modality Effects in Second Life: The Mediating Role of Social Presence and the Moderating Role of Product Involvement

Abstract The rapid growth of virtual worlds is one of the most recent Internet trends. Some distinguishing features of virtual environments include the employment of avatars and multimodal communication among avatars. This study examined the effects of the modality (text vs. audio) of message presentation on people's evaluation of spokes-avatar credibility and the informational value of promotional messages in avatar-based advertising inside 3D virtual environments. An experiment was conducted in the virtual Apple retail store inside Second Life, the most popular and fastest growing virtual world. The author designed a two-group (textual advertisement vs. auditory advertisement) comparison experiment by manipulating the modality of conveying advertisement messages. The author also created a spokes-avatar that represents a real-life organization (Apple) and presents promotional messages about its innovative product, the iPhone. Data analyses showed that (a) textual modality (vs. auditory modality) resulted...
Leading British Statisticians of the Nineteenth Century

Abstract This paper explores statistical contributions of eleven outstanding British statisticians of the nineteenth, century. They are Playfair, Porter, Babbage, Farr, Guy, Newmarch, Jevons, Rawson, Galton, Giffen, and Edgeworth. This treatment represents one aspect of British statistical thought not previously developed.
Temperature-Dependent Kinetic Isotope Effects in the Gas-Phase Reaction: OH + HBr

The temperature dependence of the hydrogen transfer rate coefficients for the reactions: OH + HBr (Reaction 1), OD + HBr (Reaction 2), OH + DBr (Reaction 3), and OD + DBr (Reaction 4) have been investigated at temperatures between 120 and 224 K using a pulsed uniform supersonic flow monitoring hydroxyl reactive loss. The lack of observed isotopic scrambling indicates the reaction occurs by H/D atom transfer from HBr/ DBr at all temperatures. The rate coefficients demonstrate little temperature dependence above 200 K, but strong inverse temperature behavior below 200 K. The current work provides unequivocal experimental evidence of temperature dependent and inverse primary and secondary kinetic isotope effects (kH/ kD < 1) at low temperatures. The observed kinetic isotope ratios, kH/kD, at 120 K are for primary substitution on HBr; k1/k3 ) 1.00 ((0.17) and k2/k4 ) 0.46 ((0.08), while for secondary substitution on OH; k1/k2 ) 0.94 ((0.20) and k3/k4 ) 0.43 ((0.05). At the lowest temperature employed (120 K), deuterated reactants react as fast or faster than their natural hydrogen isotopomer and there is no significant difference between the primary and secondary kinetic isotope effect. The results are discussed within the framework of recent theoretical models.
“Dummes Geld”: Money, Grain, and the Occupation of Romania in WWI

Romania entered World War I at a difficult moment for the Central Powers. The offensive against Verdun had been an extraordinarily bloody stalemate, one that sapped the officer corps' confidence in the leadership of General Erich von Falkenhayn. In June, Russia launched its great Brusilov offensive, pushing Austria-Hungary to the verge of capitulation. Soon thereafter, the British offensive against the Somme, itself a blood-soaked disaster, nonetheless revealed an astounding Entente advantage in war material. The first part of 1916 had not been kind to the armies of the Dual Alliance.
New paradigms in the strategic planning of corporate information systems

All industries have certain main functions in common: marketing, sales, new product development, production, quality control, and so forth: However, the way in which these functions are linked to each other differs from one industry to another. In this paper, the author concentrates on the links between sales, design, production and quality in three industries in which he has personally worked for twenty years: the automobile, media-communication and semiconductor industries. Differences in the way in which these main functions are linked dictate that distinct information systems strategies be customized for each industry. Two considerations constrain the planning and design of the information system that will be most profitable for a particular industry. These are: (1) the special position of that industry in its market; and consequently (2) the speed of linkage required between the different functions of the company, as well as the characteristics of the information that passes between the functions. These factors are fundamental for decision-making for planning. He is convinced that these differences must be focused upon when planning and designing information systems and investing in technology in order to obtain a competitive advantage.
Impact of Medical Therapy on Atheroma Volume Measured by Different Cardiovascular Imaging Modalities

Atherosclerosis is a systemic disease that affects most vascular beds. The gold standard of atherosclerosis imaging has been invasive intravascular ultrasound (IVUS). Newer noninvasive imaging modalities like B-mode ultrasound, cardiac computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) have been used to assess these vascular territories with high accuracy and reproducibility. These imaging modalities have lately been used for the assessment of the atherosclerotic plaque and the response of its volume to several medical therapies used in the treatment of patients with cardiovascular disease. To study the impact of these medications on atheroma volume progression or regression, imaging modalities have been used on a serial basis providing a unique opportunity to monitor the effect these antiatherosclerotic strategies exert on plaque burden. As a result, studies incorporating serial IVUS imaging, quantitative coronary angiography (QCA), B-mode ultrasound, electron beam computed tomography (EBCT), and dynamic contrast-enhanced magnetic resonance imaging have all been used to evaluate the impact of therapeutic strategies that modify cholesterol and blood pressure on the progression/regression of atherosclerotic plaque. In this review, we intend to summarize the impact of different therapies aimed at halting the progression or even result in regression of atherosclerotic cardiovascular disease evaluated by different imaging modalities.
Current distribution in superconducting thin-film strips

A closed-form expression is presented for the current distribution in an isolated strip made from a superconducting thin film with thickness less than a few penetration depths. This equation gives a good approximation within certain limits for the resistance and inductance per unit length of superconducting striplines and microstrip lines. Both the ac resistance of an isolated superconducting strip and the resistance per unit length of a superconducting stripline calculated using this closed-form expression agree well with the numerical results generated by the modified Weeks' method. The possibility of using this expression along with the integral equation method to develop an efficient full-wave method for analyzing superconducting planar transmission lines is discussed. >
Intraoperative small bowel length measurements and analysis of demographic predictors of increased length

Few studies have measured small bowel length (SBL) in live humans and many textbooks base their “normal” SBL values on cadaver data. Here, we present a series of intraoperative SBL measurements and analyze predictors of increased length. SBL from ligament of Treitz to ileocecal valve was measured in patients undergoing laparotomy for colorectal resection. Patients with Crohn's disease and those who had undergone prior bowel resections were excluded. In the 240 patients studied, mean SBL was 506 ± 105 (285–845) cm. Height was positively associated with increased SBL (P < 0.001) and men had longer SBL than women (533 vs. 482 cm, P < 0.001). A multivariate linear regression model using patient sex, age, height and weight was significant (P = 0.001) and the predictors explained 8% of the variance in SBL. In this model, only height was independently predictive of increased SBL (P = 0.03). Correlation results differed between sexes. In men, height correlated with increased SBL (r = 0.20; P = 0.03), whereas in women it did not. In men, age had a positive correlation with SBL at a trend level (r = 0.17; P = 0.08), whereas in women age had a negative correlation with SBL (r = −0.18; P = 0.04). The mean SBL was 506 cm in live patients, as compared with the 600–700 cm range derived from prior cadaver studies. Male sex and height had positive correlations with SBL. SBL may decrease with age in women but not in men. Clin. Anat. 26:827–832, 2013. © 2013 Wiley Periodicals, Inc.