cssi/SciSciGPT-SciSciNet huggingface dataset:
Analog and Digital Instrumentation

The sections in this article are Electrical Control Electronic Principles Electronic Electrical Control Potentiostat Circuits Galvanostatic Circuits Signal Transduction Alternate Control Circuits Ohmic Drop Compensation Current Interruption Positive Feedback Control Loop Frequency Response Effect of Reference Position Positive Feedback Stability Other Destabilizing Conditions Excitation Signals and Data Acquisition Excitation Signals Data Acquisition Microcomputer Control and Storage Example Instrument Conclusion
Calculation of small-sample weibull tolerance bounds for accelerated testing

In this paper it is assumed that in the range of interest the Arrhenius model or the inverse power law, or more generally, some known polynomial function relates a specified function of level of stress and the logarithm of time-to-failure. The number of stress levels at which testing is performed is assumed to be at least one more than the degree of the polynomial, and the distribution of time-to-failure at these stress levels and at the nominal level is assumed to be two-parameter Weibull with equal shape parameter and scale parameter varying with stress level. The numbers of tests made at the various stress levels need not be equal, but more than a single test must be made at one or more levels. Testing may be censored, even progressively censored, in some cases,For this model, a simple procedure is developed for calculating approximate small-sample lower tolerance bounds (confidence bounds for distribution percentiles) corresponding to the nominal stress level These calculations can be made at the same...
Review of Semiconductor Physics

The aim of this chapter is a brief discussion of some topics in semiconductor physics that will be useful in our discussion of applications. Since it is assumed that the reader has had an introductory course in solid state physics at the level of the book by Kittel,(1) some of the chapter will be review material. However, since some of the topics may be new to some readers, references to more complete and/or advanced treatments are given.
Local and distributed PiB accumulation associated with development of preclinical Alzheimer's disease.

Amyloid-beta plaques are a hallmark of Alzheimer's disease (AD) that can be assessed by amyloid imaging (e.g., Pittsburgh B compound [PiB]) and summarized as a scalar value. Summary values may have clinical utility but are an average over many regions of interest, potentially obscuring important topography. This study investigates the longitudinal evolution of amyloid topographies in cognitively normal older adults who had normal (N = 131) or abnormal (N = 26) PiB scans at baseline. At 3 years follow-up, 16 participants with a previously normal PiB scan had conversion to PiB scans consistent with preclinical AD. We investigated the multivariate relationship (canonical correlation) between baseline and follow-up PiB topographies. Furthermore, we used penalized regression to investigate the added information derived from PiB topography compared to summary measures. PiB accumulation can be local, that is, a topography predicting the same topography in the future, and/or distributed, that is, one topography predicting another. Both local and distributed PiB accumulation was associated with conversion of PiB status. Additionally, elements of the multivariate topography, and not the commonly used summary scalar, correlated with future PiB changes. Consideration of the entire multivariate PiB topography provides additional information regarding the development of amyloid-beta pathology in very early preclinical AD.
An algorithm for computer modeling of coupled multiconductor transmission line networks

A technique for computer modeling and analysis of coupled transmission line networks is presented. The method is based on representing the coupled transmission line network as a coupled tree data structure. By using recursive tree transversal techniques, the network is solved in two passes. In the first pass, the impedances at all nodes are computed and stored in the data structure for that node. For cases where the coupled lines are connected to uncoupled lines, the impedance looking into the uncoupled line subtree must also be computed and stored. In the second pass, starting at the source the voltages and currents are computed by transversing the tree and using the impedances calculated in the first pass. The technique was applied to a particular coupled system, and the effects of coupling calculated using the technique agreed well with the results one would expect from the network. The technique is especially useful in the analysis of coupling in multiconductor transmission line networks with many branches and mixed transmission line characteristics. >
New coplanar waveguide/stripline feed network for seven patch hexagonal CP subarray

A novel CPW-to-stripline post coupler is demonstrated. This device couples the output power from a coax-to-CPW inphase seven-way radial power divider to a balanced stripline line stretcher and together forms a multilayer probe-type feed network. The feed network excites a seven-patch hexagonal circularly polarized (CP) subarray. The measured return loss and insertion loss of the coupler are better than 17 dB and 0.25 dB at the design frequency of 2.875 GHz. The measured on-axis axial ratio for the left hand circular polarization (LHCP) is 1.5 dB and the 3 dB beam widths are 36 deg in the principal planes of the subarray. The gain of the subarray is 13 dB. The input return loss of the subarray is better than 10 dB.
A partial map of the barley genome incorporating restriction fragment length polymorphism, polymerase chain reaction, isozyme, and morphological marker loci.

Nine low copy number genomic DNA clones, a ribosomal sequence, and seven cDNA clones were found to identify polymorphisms in cultivated barley (Hordeum vulgare L.). An F2 population consisting of 1...
Modeling the Spatial Distribution of Mosquito Vectors for West Nile Virus in Connecticut, USA

The risk of transmission of West Nile virus (WNV) to humans is associated with the density of infected vector mosquitoes in a given area. Current technology for estimating vector distribution and abundance is primarily based on Centers for Disease Control and Prevention (CDC) light trap collections, which provide only point data. In order to estimate mosquito abundance in areas not sampled by traps, we developed logistic regression models for five mosquito species implicated as the most likely vectors of WNV in Connecticut. Using data from 32 traps in Fairfield County from 2001 to 2003, the models were developed to predict high and low abundance for every 30 x 30 m pixel in the County. They were then tested with an independent dataset from 16 traps in adjacent New Haven County. Environmental predictors of abundance were extracted from remotely sensed data. The best predictive models included non-forested areas for Culex pipiens, surface water and distance to estuaries for Cx. salinarius, surface water and grasslands/agriculture for Aedes vexans and seasonal difference in the normalized difference vegetation index and distance to palustrine habitats for Culiseta melanura. No significant predictors were found for Cx. restuans. The sensitivity of the models ranged from 75% to 87.5% and the specificity from 75% to 93.8%. In New Haven County, the models correctly classified 81.3% of the traps for Cx. pipiens, 75.0% for Cx. salinarius, 62.5% for Ae. vexans, and 75.0% for Cs. melanura. Continuous surface maps of habitat suitability were generated for each species for both counties, which could contribute to future surveillance and intervention activities.
The reconstruction of outerplanar graphs

Abstract Ulam's conjecture is that a graph G with at least three vertices can be reconstructed from the family of subgraphs of G obtained by deleting single vertices of G . This paper proves the conjecture for G outerplanar, by working first with partially labeled graphs and then applying the results obtained to the unlabeled case.
Influence of daughter state instability on parent state decay rate

Abstract The Weisskopf–Wigner solution of a two-level decay is extended to a simple three-level model. We calculate the influence of daughter state decay on the decay rate of the initial state. We show that this effect is dependent on the exact form of the spectral density functions, precluding a general quantum Zeno effect.
The formation of free and lipid myo-inositol in the intact rat.

Abstract 1. 1. The incorporation of 14 C into the free and lipid-bound myo-inositol of rat brain, liver, kidney and blood was measured after the injection of [ 14 C 6 ]glucose and other radioactive substances into young and adult rats. 2. 2. In brain, radioactivity appeared in free inositol and in lipid-inositol bound in phosphatides and phosphatidopeptides after the injection of [ 14 C 6 ]glucose. Highest specific activity was observed in free blood inositol. The time curves of incorporation are consistent with the involvement of free inositol in the assembly of inositol phosphatide in brain; however, the inositol-containing lipids in phosphatidopeptides appear to belong to a different pool. 3. 3. Both free and phosphatide inositol of liver and kidney also became labeled, with higher activity occurring in the free inositol. Specific activities in young rats were about twice as great as in adult ones. Sodium [2- 14 C]pyruvate gave rise to labeled inositol (both free and bound) in brain, liver and kidney, but no incorporation was obtained with sodium [1- 14 C]acetate or sodium [6- 14 C]glucuronate. 4. 4. In addition to these findings data on the amounts of inositol isolated and on the incorporation of 14 C of glucose and pyruvate into phosphatide glycerol are presented.
Studies of Controlled Cyclic Distillation: I. Computer Simulations and the Analogy with Conventional Operation

Abstract Computer simulations of a controlled cycling rectification still were run to determine the theoretical effects of local point efficiency, slopes of the equilibrium and operating lines, amount of liquid dropped during the liquid-flow period, and other parameters on over-all column and individual plate efficiencies. It is shown that, although the Murphree vapor efficiency of a plate at any instant of time is assumed to be constant and equal to the local point efficiency, the effective plate efficiency based on the resulting liquid-phase plate compositions is usually significantly greater than the point efficiency. This leads to the improved separating ability achieved in controlled cyclic operation. The existence of a precise analogy between controlled cyclic distillation and conventional distillation with liquid-phase concentration gradients across the plates of the column is shown. In essence, this analogy reduces to the substitution of time as the independent variable in the former case for dist...
Measuring Differences among Non-Randomized Groups: An Epidemiological Model for Identifying Successful School Programs

Random assignment of students to innovative educational programs is not always possible in establishing proper and adequate control groups; therefore, it is recommended that the biomedical model of adjusted statistics designed to overcome the well-known difficulty educational investigators face when attempting to randomize subjects be adopted. The model’s utility is demonstrated by using hypothetical data for fifth grade students tested by criterion and norm referenced tests. Results indicate that the adjusted discrepancies between group statistics are considerably smaller than is indicated by inspection of raw, or unadjusted, sample values. The educational analogue of the biomedical model of adjusted rates provides a way to obtain a more accurate estimate of program success or failure when comparisons across classrooms or other units are desirable.
Double-photoionization studies of Ne, O, and N from threshold to 280 eV.

The photoionization cross sections for double ionization of Ne by single photons have been measured from threshold to 280 eV. The results presented are in considerable variance with other published data. These cross sections are compared with those for ${\mathrm{N}}^{2+}$ and ${\mathrm{O}}^{2+}$. It is found that the ratio of the oscillator strength for double ionization to the total photoionization oscillator strength for each of these atoms is proportional to N-1, where N is the total number of electrons in the atom.
Tilapia Tolerance of Saline Waters: A Review

Abstract Members of the family Cichlidae that are generally referred to as tilapias (Tilapia spp.) characteristically demonstrate some degree of euryhalinity. A survey of existing literature indicates that Tilapia zilli and Tilapia mossambica are among the most salinity-tolerant species, although neither is among the most desirable for culture. A tolerance for high salinity has been demonstrated in at least some crosses that produce red hybrid tilapia. Most known heritage crosses with that result to date have involved T. mossambica. The red hybrid may become a preferred culture fish in brackish and seawater systems as well as in fresh water.
Shifts in Hmong Culture: Competing Medical Frameworks

The objective of this study was to examine how language contraction, acculturation, and perception of modernity impact medicinal practices among younger and older generations of Hmong. Focus groups were conducted with newly immigrated and well established Hmong adults (n = 69) and children (n = 68) in St. Paul/Minneapolis, MN, USA. Dominant themes were language contraction and cultural loss, with subthemes on household dynamics, the educational system, and Western versus traditional Hmong medicinal practices. As younger generations acculturate to the United States (US) environment, there is potential for a restructuring of their medical culture resulting in a loss or silencing of pertinent cultural information regarding traditional medicine and therapies. The information from this study will be useful for educators, community leaders and health professionals to better understand changes occurring within the Hmong culture as traditions and cultural practices acculturate to the US environment.
Chasing contrast molecules: A 45-year quixotic quest1

Now having attained a certain age I am reminded that there are some perks that come with the package. One of them is allowable reminiscence. This is doubly sweet when the reminiscence is requested and the teller is not distracted by eye glaze-over. Fifty years ago the Swedes led the world in the techniques of contrast molecule (CM) “special procedures.” At that time I determined to take away these procedures from the surgeons in my hospital and accordingly obtained an invitation to Sweden to observe and practice their techniques. On my return I began to put these into practice and, aware of the adverse reactions that might result, consulted the library to find what was known about these and how to treat them, should they occur. To my amazement I found a startling dearth of information and thereupon decided that I had a great deal of work to do if I intended to continue to do these procedures with conscience. Having made this decision, I entered into a world that was remote from my original thinking about radiology practice and that subsequently gifted me with the joys (and sorrows) that come from the raised enthusiasms of research. In this article I will try to cover some of the work that particularly stimulated me and in so-doing will attempt to present a coherent scheme that explains most of the mechanisms which account for what we experience with CM in clinical practice and have falsely termed “anaphylactoid reactions.”
It's alive!

Inanimate things are coming to life. However, these stirrings are not Shelley's Frankenstein or Asimov's humanoid robots. This new awakening is more like Walt Disney's Sorcerer's Apprentice: the simple objects that surround us are gaining sensors, computational powers, and actuators. As a result, desks and doors, televisions and telephones, cars and trains, eyeglasses and shoes, and even the shirts on our backs—all are changing from static, inanimate objects into adaptive, reactive systems that are more useful and efficient.
Full-Scale Seismic Testing of Piles in Improved and Unimproved Soft Clay

A full-scale field investigation was performed to determine the effects of soil improvement on the seismic resistance of piles in soft clay. A soil improvement method, called cement deep soil mixin...
Allopurinol initiation and all-cause mortality in the general population

Background Allopurinol is the most commonly used urate-lowering therapy, with rare but potentially fatal adverse effects. However, its impact on overall mortality remains largely unknown. In this study, we evaluated the impact of allopurinol initiation on the risk of mortality among individuals with hyperuricaemia and among those with gout in the general population. Methods We conducted an incident user cohort study with propensity score matching using a UK general population database. The study population included individuals aged ≥40 years who had a record of hyperuricaemia (serum urate level >357 μmol/L for women and >416 μmol/L for men) between January 2000 and May 2010. To closely account for potential confounders of allopurinol use and risk of death, we constructed propensity score matched cohorts of allopurinol initiators and comparators (non-initiators) within 6-month cohort accrual blocks. Results Of 5927 allopurinol initiators and 5927 matched comparators, 654 and 718, respectively, died during the follow-up (mean=2.9 years). The baseline characteristics were well balanced in the two groups, including the prevalence of gout in each group (84%). Allopurinol initiation was associated with a lower risk of all-cause mortality (matched HR 0.89 (95% CI 0.80 to 0.99)). When we limited the analysis to those with gout, the corresponding HR was 0.81 (95% CI 0.70 to 0.92). Conclusions In this general population study, allopurinol initiation was associated with a modestly reduced risk of death in patients with hyperuricaemia and patients with gout. The overall benefit of allopurinol on survival may outweigh the impact of rare serious adverse effects.
β-Bungarotoxin inhibition of calcium accumulation by rat brain mitochondria

Abstract Electrophysiological studies have shown that β-bungarotoxin modifies the release of neurotransmitter from mammal ian motor-nerve terminals. In this paper we demonstrate that β-bungarotoxin can also inhibit calcium accumulation into sub-cellular fractions from rat brain at very low concentrations (2–8 pmoles toxin/mg protein). Since the calcium uptake which is inhibited has the characteristics of mitochondrial calcium accumulation (DNP-sensitivity, succinate stimulation), we conclude that the toxin affects the mitochondria. We suggest that the electrophysiological observations are consistent with direct or indirect inhibition by toxin of mitochondrial calcium uptake.
Superresolution imaging applied to ultrasonic scattering

A new method for solving ultrasonic inverse scattering problems is proposed. By focusing a model constraint on the impedance profile the authors find a set of non-linear equations relating the reflection coefficient to the parameters of the model constraint. The non-linear part of the equations can be reduced to a linear prediction spectral estimation problem by means of the Born approximation, and the remaining linear part can be solved using least squares. Results for model calculations are presented for perfect data and noisy data.
Severe Gastric Distension in Seven Patients with Cerebral Palsy

This is a report of two children who had severe recurrent gastric distension and vomiting, and five who experienced severe gastric distension without vomiting. Two of the five died during an episode of acute gastric distension. All had marked nutritional depletion, and severe spastic quadriplegia due to either cerebral palsy or acquired brain injury. None of the patients had significant gastroesophageal reflux. Positioning the patients in the left lateral decubitus position temporarily relieved their obstructions. Complete resolution of the distension and/or vomiting did not occur until after adequate weight gain. Loss of fat stores may lead to this type of recurrent gastric distension.
Effects of paired and unpaired trials beyond the peak CR on acquisition and extinction of a classically conditioned SCR

The present experiment investigated the postpeak CR attenuation process during classical conditioning of the SCR and its relationship to subsequent extinction. Either paired trials were continued or unpaired trials were introduced following a subject’s peak CR for an additional 2 or 16 trials. Two control groups received uniformly unpaired presentations of the CS and the UCS. All six groups were then given extinction trials. Stronger resistance to extinction with 2 as contrasted to 16 acquisition trials was demonstrated only with the postpeak paired group. Disassociation of the CS and the UCS beyond the peak CR eliminated the effects of conditioning during extinction. Strong resistance to extinction, therefore, appears to be associated with very few acquisition trials past the peak CR, and maximum CR strength is achieved if those trials are paired rather than unpaired. An acceleration of the CR attenuation process during postpeak unpaired trials and traces of a strong UCS arousal response were offered as explanations for the results.
Maize recombinant C4-pyruvate,orthophosphate dikinase: Expression in Escherichia coli, partial purification, and characterization of the phosphorylatable protein.

The gene for C4-pyruvate,orthophosphate dikinase (PPDK) from maize (Zea mays) was cloned into an Escherichia coli expression vector and recombinant PPDK produced in E. coli cells. Recombinant enzyme was found to be expressed in high amounts (5.3 U purified enzyme-activity liter-1 of induced cells) as a predominantly soluble and active protein. Biochemical analysis of partially purified recombinant PPDK showed this enzyme to be equivalent to enzyme extracted from illuminated maize leaves with respect to (i) molecular mass, (ii) specific activity, (iii) substrate requirements, and (iv) phosphorylation/inactivation by its bifunctional regulatory protein.
The problem of subwavelength imaging by Veselago lens

Abstract A brief discussion of the imaging by the Veselago lens is given with a special attention to the absorption inside the lens. The near field regime is considered as the best candidate for the subwavelength imaging. A near field lens with a virtual focus is discussed in the original part of the paper. It is shown that it does not have some disadvantages of a lens with a real focus. A small absorption is not crucial for such a lens. The theory can be created without taking into account the imaginary part of the dielectric constant ϵ . The field does not diverge near the focus as Im ϵ ⇒ 0 as it does in the lens with the real focus. Thus, the total absorption in this case may be significantly less. The lens or the sequence of the lenses can be used for three-dimensional image transmission.
A Method That Combines Internal State Estimation and External Network Modeling

A method that combines internal state estimation and external network modeling is developed. The external system is represented by an unreduced load flow model. One state estimation covering both the internal system and the external system is used. The external system operating data on power injections and bus voltages are entered as pseudo-measurements. At each iteration the set of active pseudo- measurements are selected to conform with the specified variables in a load flow program. Because such a set of non-redundant measurements is used, the internal state estimation is not affected by the external system pseudo-measurements. External generation MVAR and controlled bus voltage limits are enforced. A technique is developed to make a pseudo-measurement dormant. Using the dormant-measurement technique, it is possible to maintain the same external system state estimation formulation while the PV-PQ switching takes place from iteration to iteration. The method can easily be implemented by modifying an existing state estimation program. It has been implemented in a fast model-decoupled estimation program. Because of the dormant measurement technique, the constant gain matrix evaluated at flat voltage is used in every iteration. The method has been tested on the IEEE 14- bus, 30-bus, and Brazilian 66-bus systems. Excellent results are obtained. The number of iterations for the method to converge is usually the same as the regular state estimation runs. Thus the method presented here achieves simultaneously the internal state estimation and the external network modeling without adversely affecting the internal state estimation.
Fracture mechanics parameters for cracks on a slightly undulating interface

Typical bimaterial interfaces are non-planar due to surface facets or roughness. Crack-tip stress fields of an interface crack must be influenced by non-planarity of the interface. Consequently, interface toughness is affected. In this paper, the crack-tip fields of a finite crack on an elastic/rigid interface with periodic undulation are studied. Particular emphasis is given to the fracture mechanics parameters, such as the stress intensity factors, crack-tip energy release rate, and crack-tip mode mixity. When the amplitude of interface undulation is very small relative to the crack length (which is the case for rough interfaces), asymptotic analysis is used to convert the non-planarity effects into distributed dislocations located on the planar interface. Then, the resulting stress fields near the crack tip are obtained by using the Fourier integral transform method. It is found that the stress fields at the crack tip are strongly influenced by non-planarity of the interface. Generally speaking, non-planarity of the interface tends to shield the crack tip by reducing the crack-tip stress concentration.
Constancy of Urea Clearances in Dogs Following Surgical Anesthesias with Cyclopropane, Ether, and Chloroform.∗

SummaryOn a group of 5 adult female dogs maximal urea clearance determinations following anesthetization with cyclopropane, ether, or chloroform have shown no significant variations over a period of 8 months from control values. Ninety-one control determinations made on the 5 animals before anesthetization gave average clearance values of 34.9±6.1 cc per square meter per minute with a coefficient of variation of 17.6 and 83 determinations made after 19 anesthesias with the three agents averaged 35.2±5.9 cc per square meter per minute with a coefficient of variation of 16.6.†
Methods and issues in conducting breed-specific canine health surveys

Abstract Three breed-specific canine health surveys were conducted (one telephone, two mailed). The surveys were initiated by breed club members and were developed in close collaboration with the clubs. Two sampling frames were membership in special-interest or breed clubs and dog registration lists. One club used both breed club and registration lists. Few differences in demographic variables were found for these two sampling frames. The response percentages for the different questionnaires and, when available, the reasons for non-response were documented. Basic principles of questionnaire design were applied in this setting; reasons for the designs chosen and their advantages and disadvantages were summarized. Feedback from the clubs about survey results was positive. Four specific outcomes were measured: (1) some data were developed as a measure for individual breeders to compare their animals' health problems with the breed as a whole; (2) the surveys documented some common health problems which enabled the clubs to focus research and education; (3) the surveys provided a forum for discussion of health problems within the breed; (4) club Health and Welfare Committees were satisfied by their ability to gain simple health-related information about their breed in a relatively inexpensive and timely fashion. These data are critical to document disease prevalences in dogs for future research and improvement of the quality of pure-bred dogs.
Pressure and temperature‐based adaptive observer of air charge for turbocharged diesel engines

SUMMARY In this paper we design an adaptive air charge estimator for turbocharged diesel engines using intake manifold pressure, temperature and engine speed measurements. This adaptive observer scheme does not depend on mass air flow sensors and can be applied to diesel engines with no exhaust gas recirculation (EGR). The performance of the adaptive scheme is shown in simulations to be comparable to conventional air charge estimation schemes if perfect temperature measurements are available. The designed scheme cannot estimate fast transients and its performance deteriorates with temperature sensor lags. Despite all these difficulties, this paper demonstrates that (i) the proposed scheme has better robustness to modelling errors because it provides a closed-loop observer design, and (ii) robust air charge estimation is achievable even without air flow sensors if good (fast) temperature sensors become available. Finally, we provide a rigorous proof and present the implementation challenges as well as the limiting factors of this adaptation scheme and point to hardware and temperature sensor requirements. Copyright # 2004 John Wiley & Sons, Ltd.
Meta-diagnosis: towards a hermeneutical perspective in medicine with an emphasis on alcoholism.

This essay argues that making a diagnosis in medicine is essentially a hermeneutic enterprise, one in which interpretation skills play a major part in understanding a disease. The clinical encounter is an event comprised of two ‘voices’; one is the voice of science which is grounded in empiricism, the other is that of human experience, which is grounded in story-telling and the interpretation of those stories.
Synthesis and structure–activity relationship of a novel series of heterocyclic sulfonamide γ-secretase inhibitors

Abstract γ-Secretase inhibitors have been shown to reduce the production of β-amyloid, a component of the plaques that are found in brains of patients with Alzheimer’s disease. A novel series of heterocyclic sulfonamide γ-secretase inhibitors that reduce β-amyloid levels in cells is reported. Several examples of compounds within this series demonstrate a higher propensity to inhibit the processing of amyloid precursor protein compared to Notch, an alternative γ-secretase substrate.
Chorioretinal vascular oxygen tension changes in response to light flicker.

Oxygen consumption is a major factor in retinal metabolism. Oxygen is delivered to the retinal tissue by the choroidal and retinal circulations. The supply of oxygen is adapted according to the metabolic activity of the retinal tissue. Visual stimulation by light flicker increases the metabolic demand of the inner retina.1–5 Therefore, changes in the PO2 of the chorioretinal vascular beds are likely to be induced by light flicker, particularly in the retinal circulation, which supplies the inner retina. Light flicker–induced changes in the intravascular PO2 have been reported based on the blood oxygen level–dependent signals on magnetic resonance imaging, which only provide a combined measurement in all the chorioretinal vasculatures.6 Although optic nerve head PO2 increases from light flicker with phosphorescence imaging,7 PO2 changes in the retinal arteries, veins, capillaries, and the choroid have not been investigated. Increased retinal blood vessel diameter and blood flow in response to light flicker, under normal physiological conditions, have been demonstrated,8–10 and reduced retinal hemodynamic response to flicker has been reported in patients with hypertension, glaucoma, and diabetes.11–13 According to the Fick principle, retinal tissue oxygen consumption equals the product of retinal blood flow and arteriovenous oxygen content difference.14 Therefore, measuring retinal intravascular PO2 separately in the artery and in the vein, coupled with the knowledge of blood flow, may provide a better means for assessing retinal oxygen consumption than blood flow measurement alone. In the retina, a measurable efflux of oxygen from the arterial vasculature has been reported.15,16 Moreover a reduction in the arterial PO2 gradient along the vessel caused by increased blood flow has been demonstrated in isolated small arterial preparations.17 Therefore, arterial PO2 changes resulting from altered blood flow must be considered in interpreting the retinal intravascular PO2 changes in response to light flicker. We have previously developed a technique for measuring PO2 separately in the retinal and choroidal vasculatures.18–20 The purpose of the present study was to measure PO2 changes in the chorioretinal vasculatures and to determine the retinal arteriovenous PO2 difference in response to light flicker. Given that arterial PO2 is influenced by oxygen diffusion,15,17 variations in retinal arterial PO2 along blood vessels in the absence of visual stimulation were also investigated.
Practitioners' perspectives on effective practices for Hispanic teenage pregnancy prevention.

CONTEXT: In the United States, the pregnancy rate and birthrate of Hispanic teenagers are higher than those of other races and ethnicities. Although recommendations for culturally appropriate pregnancy prevention programs are commonplace, little is known about how practitioners address such recommendations. METHODS: In individual interviews, 58 teenage pregnancy prevention practitioners who work primarily with Mexican American female teenagers from two regions in California were asked about their understanding of recommendations for best practices and discussed the strategies they have used and challenges they have faced in implementing the recommendations. Qualitative methods were used to categorize responses and identify themes. RESULTS: Practitioners indicated that knowledge and awareness of Hispanic culture are essential, as is commitment to teenagers and their needs. They regard activities that encourage educational and career achievement as critical program components, and view both male partners' and family members' involvement in programs as important but challenging. Furthermore, practitioners feel that the implicit program goals of continued education and female self-sufficiency are often at odds with traditional Hispanic cultural values. CONCLUSIONS: Practitioners have valuable insight into the reality of implementing culturally sensitive programs. Programs need to balance the often competing values and goals of prevention programs with those of Hispanic youth culture and experiences.
The Wolff-Parkinson-White (WPW) syndrome with supernormal conduction through the anomalous BYPASS.

An unusual case of WPW syndrome demonstrating a supernormal phase of conduction of the anomalous bypass is reported. It is suggested that the supernormality in the bypass tissue was due to concealed retrograde conduction into the bypass of the preceding normal ventricular wave of excitation.
MULTIPLE PHONON NUCLEAR SPIN EXCITATION IN GaAs

Spin transitions may be induced by interaction of the nuclear quadrupole moment (NQM) with time varying electric field gradients (EFG). These EFG occur when phonons distort the lattice. There are three processes by which phonons of appropriate frequency may excite nuclear spin transitions. (1) Direct interaction of a phonon at the Larmor frequency v 0 or at 2 v 0 (e.g. a phonon at 2 v 0 is absorbed exciting an upward Δ m = +2 spin transition). (2) The indirect interaction with the NQM (Raman process) with two phonons v A and v B such that v A ± v B = v 0 or 2 v 0 (e.g. v A is absorbed with an upward spin transition at 2 v 0 , then phonon v B = v A — 2 v 0 is emitted). (3) An anharmonic three phonon interaction where v A ± v B → v C + (other phonons). If v C = v 0 or 2 v 0 then through (1) spin transitions can subsequently occur. We have experimentally observed that r.f. voltage applied to 10 mc and 25 mc transducers bonded to opposite faces of a GaAs single crystal reduces the As 75 nuclear magnetization (2 v 0 = 15 mc). The experimental conditions of this observation are predicted within 50 per cent using the Raman process theory. The contribution of the anharmonic three-phonon process to this observation will be discussed in addition to other experimental conditions under which this anharmonic process is observed.
Genotyping and genomic profiling of non-small-cell lung cancer: implications for current and future therapies.

Substantial advances have been made in understanding critical molecular and cellular mechanisms driving tumor initiation, maintenance, and progression in non–small-cell lung cancer (NSCLC). Over the last decade, these findings have led to the discovery of a variety of novel drug targets and the development of new treatment strategies. Already, the standard of care for patients with advanced-stage NSCLC is shifting from selecting therapy empirically based on a patient's clinicopathologic features to using biomarker-driven treatment algorithms based on the molecular profile of a patient's tumor. This approach is currently best exemplified by treating patients with NSCLC with first-line tyrosine kinase inhibitors when their cancers harbor gain-of-function hotspot mutations in the epidermal growth factor receptor (EGFR) gene or anaplastic lymphoma kinase (ALK) gene rearrangements. These genotype-based targeted therapies represent the first step toward personalizing NSCLC therapy. Recent technology advances in multiplex genotyping and high-throughput genomic profiling by next-generation sequencing technologies now offer the possibility of rapidly and comprehensively interrogating the cancer genome of individual patients from small tumor biopsies. This advance provides the basis for categorizing molecular-defined subsets of patients with NSCLC in whom a growing list of novel molecularly targeted therapeutics are clinically evaluable and additional novel drug targets can be discovered. Increasingly, practicing oncologists are facing the challenge of determining how to select, interpret, and apply these new genetic and genomic assays. This review summarizes the evolution, early success, current status, challenges, and opportunities for clinical application of genotyping and genomic tests in therapeutic decision making for NSCLC.
Reproductive Systems and Sibling Competition in Plants

Competition among relatives can modify the genetic structure of plant populations; in turn, competitive outcomes can depend on the genetic relatedness of the individuals competing. The offspring from individual parents exhibit a continuum of genetic relatedness, depending on parental reproductive systems. Competition among relatives may have evolutionary significance as a selection pressure; sibling competition, for example, has been invoked to explain the evolution of sexual systems, seed packaging within fruits, seed dispersal dimorphisms, and germination behavior. Density-dependent fitness consequences of sibling competition have been documented in a population of the annual grass Sporobolus vaginiflorus. This species produces seeds matured in cleistogamous spikelets within leaf sheaths along tillers in autumn: when seeds along the tillers of a maternal parent (i.e. a sibship) germinate in situ the following spring in close proximity to one another, sibling competition results in a high-density zone centered around the original senescent parent. Both intra- and intersibship interactions can occur within a population. Although fitness is much reduced for siblings inside the zone of competition, potential seed rain and net primary productivity per unit area are significantly higher relative to outside the zone. This annual is functionally analogous to a perennial ramet producer with a phalanx growth strategy and the unit of selection may be the sibling group. It is not yet known whether sibling competition is a significant selection pressure in other species, but indirect evidence suggests it may be relatively widespread.
Service Pathways for Children and Youth Meeting Criteria for Serious Emotional Disturbance

Few studies offer guidance on best practice for social workers in assessment and recommendation of treatment services for specialty mental health services within a system of care (SOC). This study examined factors associated with service assignment among a population of children and youth (N = 1,270) entering a federally funded system of care program referred to specialty mental health services. Logistic regression was used to examine the likelihood of children and youth determined in need of varying levels of care coordination services based on child factors and referral source. Older youth, youth with internalizing problems, and those referred from mental health compared to juvenile justice and schools were significantly more likely determined in need of more intensive care coordination services. Race was not significantly associated with level of care determination. Findings suggest that differences exist in level of care determination for children entering system of care referred by the juvenile justi...
The inhibition effect of cholecystokinin in human colonic lamina propria lymphocyte proliferation, and reversal by the cholecystokinin receptor antagonist L-364718

Cholecystokinin (CCK) is a potent neuropeptide hormone with activity on various gastrointestinal organs during the digestive process. It was recently suggested that CCK may also act on the immune system. In this study we investigated the effect of CCK on the human mucosal immune system as represented by colonic lamina propria lymphocytes (LPL). Our results demonstrated that CCK at concentrations of 10(-13) M to 10(-7) M inhibits thymidine incorporation into Con A-stimulated LPL DNA by up to 40%. Moreover, this inhibitory effect was reversed by the specific CCK receptor antagonist, L-364718, at concentrations of 10(-8) M to 10(-5) M. In addition, CCK did not affect DNA synthesis of LPL stimulated with phorbol ester (PDB) and calcium ionophore (ionomycin). It is postulated that the CCK effect may involve intracellular metabolic steps proximal to protein kinase C activation and calcium flux. Our results suggest that CCK may play a role in modulating the human mucosal immune system during digestion and thus, should be added to the list of the neuropeptides that affect the mucosal immune system.
Chemical effects of fission recoils. I. Energy deposition efficiencies and their dependence on surface conditions

Abstract The production of nitrogen from nitrous oxide at high density was employed to investigate the energy deposition efficiency of fission recoils produced from fission of U235 in uranium-palladium foils clad with platinum. Nitrogen production varied linearly with fission recoil dose from 1.1 × 1020 to 9.0 × 1020 eV, and was independent of density between 12.5 and 127.5 gl−1 N2O. 16.2 ± 0.8% of the fission recoil energy was deposited external to the foil. Electron microprobe analysis showed some unevenness of new foil and polymer buildup on the surface after irradiation of ethylene-oxygen mixtures. Subsequent irradiation in the presence of nitrous oxide restored some of the original efficiency. This is ascribed to chemical oxidation of the polymer induced by reactive intermediates produced from nitrous oxide.
Hybrid native phosphorescence and fluorescence spectroscopy for cancer detection

Native fluorescence of tissues in the UV and visible spectral regions has been investigated for over two decades. Native fluorescence has been demonstrated to be an accurate tools for distinguish normal tissue from malignant and pre-malignant. Prior investigations have demonstrated that there are several ratio-based algorithms, which can distinguish malignant tissue from normal with high sensitivity and specificity. 1 The wavelength combinations used in these ratios isolate the contributions from pairs of tissue fluorophors, one of which is frequently tryptophan (trp), the predominant tissue fluorophore with excitation in the UV (250-300 nm). In this work, algorithms using a combination of native fluorescence and trp phosphorescence were developed which show promise for providing enhanced detection accuracy. Using optical fibers to collect the emission from the specimen allowed interrogation of small regions of tissue, providing precise spatial information. Using a specially designed setup, specimens were excited in the UV and spectra were collected in the range of 300 to 700 nm. Three main emission bands were selected for analysis: 340 nm (trp fluorescence); 420 - 460 nm band (fluorescence from the extra cellular matrix); and 500 - 520 nm (trp phosphorescence). Normal specimens consistently exhibited a low ratio ( 15) for cancer specimens. Creating intensities ratio maps from the tissue allows one to localize the malignant regions with high spatial precision. The study was performed on ex vivo human breast tissues. The ratio analysis correlated well with histopathology.
Mouse Connexin40: Gene Structure and Promoter Analysis

A family of related connexin genes encodes the subunit gap junction proteins that form intercellular channels in different tissues. Connexin40 (Cx40) is one of these proteins, and it exhibits limited expression only in a few cells of the cardiovascular system. To begin to analyze Cx40 expression, we isolated a 3.3-kb rat Cx40 cDNA by hybridization screening of a bacteriophage library prepared from BWEM cells and isolated corresponding mouse genomic clones from a bacterial artificial chromosome library. Restriction mapping, sequencing, and comparison to the rat cDNA showed that the mouse Cx40 gene contained a short first exon, an 11.4-kb intron, and a second exon containing the complete coding region and 3'-UTR. Exon I contained only 1 base that differed between rat and mouse. Primer extension experiments yielded a single band and confirmed the position of the transcriptional start site. We obtained 1.2 kb of sequence 5' of the transcriptional start site and 400 bp 3' of exon I. Exon I was closely preceded by a consensus TATA box. The flanking sequences contained a number of potential transcription factor binding sites (including AP-1, AP-2, SP1, TRE, and p53). To identify transcriptional regulatory elements in the Cx40 promoter region, a series of DNA deletion fragments flanking exon I was prepared, subcloned adjacent to a luciferase reporter gene, and used for transient transfections of BWEM, SHM, and N2A cells. The resulting luciferase activity determinations suggested that an area of 300 bp 5' of the transcription start site acted as a basal promoter for Cx40 and that there was a strong negative regulatory element in the region from +100 to +297.
Safety and effectiveness of endovascular therapy for claudication in octogenarians

Background Advanced age (≥80 years) has been associated with adverse outcomes after lower extremity bypass for critical limb ischemia (CLI), but endovascular therapy (ET) is reported to have comparable safety across age groups. Here, we assess the safety and effectiveness of advanced age on outcomes after ET for lifestyle-limiting intermittent claudication (IC). Methods A retrospective review of a prospectively maintained institutional database (2007–2012) identified all patients undergoing ET for IC. Demographics, procedural details, and outcomes were assessed via univariate analysis and multivariate Cox regression. Effectiveness was assessed across a panel of outcome metrics including the following: overall survival, freedom from major adverse limb event (MALE), and freedom from reintervention, amputation, or restenosis (RAS). Freedom from MALE + perioperative death (MALE + POD) was the primary safety end point. Results Two hundred thirty-six patients underwent primary ET for 284 affected limbs. Of these, 46 interventions (16%) were performed in patients ≥80 years old. The average age of octogenarians treated was 84.4 years compared with 67.4 years among those aged Conclusions Although age >80 years has been identified as an independent risk factor for poor outcomes in the surgical treatment of CLI, our results suggest that ET for selected octogenarians with lifestyle-limiting claudication is as safe and effective as ET in younger patients. Advanced age alone should not prohibit consideration of ET for patients with IC.