cssi/SciSciGPT-SciSciNet huggingface dataset:
Pool sizes of the deoxynucleoside triphosphates in the sea urchin egg and developing embryo.

Abstract The four deoxynucleoside triphosphate pools in unfertilized eggs of L. pictus and S. purpuratus were measured and found to be very large, ranging from 10 −3 to 10 −2 pmoles per egg. The high levels of the individual dNTP pools are sufficient for one to eight rounds of DNA synthesis. During the first division cycle these pools fluctuate with the highest levels being attained prior to DNA synthesis. The pools then decrease just preceding or during the S period. There is a large reduction in the total cellular dNTP in later stages of development when DNA synthesis is reduced relative to the cleavage stages.
Subdivisions of the auditory cortex of the cat: The retrograde transport of horseradish peroxidase to the medial geniculate body and posterior thalamic nuclei

Each subdivision of auditory cortex was injected with horseradish peroxidase (HRP). The amount of HRP injected was varied with the result that in some cases the diffusion of HRP was restricted while in other cases, HRP diffused over an entire cortical subdivision and encroached on adjacent subdivisions. In the case of restricted diffusion only a relatively small number of thalamic cells were “labelled”; in the case of extensive diffusion many times that number of cells were labelled. Whether relatively few or many cells, the distribution of labelled cells fell into distinctive patterns. Each pattern consisted of a focus or concentration of labelled cells in one thalamic subdivision and a sparser population of labelled cells in other thalamic subdivisions. The most striking example of a pattern is produced by injecting AI. This injection resulted in a band in the ventral division of the medial geniculate body densely populated with labelled cells; but even after the smallest injection, labelled cells were also found outside the ventral division, in the magnocellular and dorsal divisions of the medial geniculate body, and in the posterior group. (The ventral extremity of the ventral division was always free of cells and this sector is likely a separate nucleus which projects to Ep.) Other patterns are produced by injecting HRP in other cortical subdivisions: temporal injections produced a concentration in the caudal division of the medial geniculate body; insular injections resulted in a concentration in the medial sector of the posterior group; AII injections led to a concentration in the magnocellular and deep dorsal divisions of the medial geniculate body; injections in ventral Ep led to a concentration of labelled cells in the dorsal division of the medial geniculate body; finally, dorsal Ep seems to be very different from the other divisions inasmuch as injections in it resulted in labelled cells in non-auditory thalamus–the pulvinar and lateral nuclei, as well as the auditory thalamus. These results lead to the following conclusions. The laminated and principal part of the ventral division of the medial geniculate body projects only to AI. Every other thalamic subdivision projects to two or more cortical subdivisions: the caudal division projects primarily to the temporal area with sparser projections to AII and Ep; the dorsal division projects primarily to Ep with sparser projections to AI, AII, and the temporal area; the medial sector of the posterior group projects primarily to the insular area and to the posterior ectosylvian gyrus; the magnocellular division of the medial geniculate body projects to every subdivision of auditory cortex, including AI and AII.
Renormalization in anti-de Sitter supersymmetry.

The one-loop renormalization of the Wess-Zumino model in four-dimensional anti--de Sitter space (AdS${)}_{4}$ is studied using a manifestly supersymmetric Pauli-Villars regularization procedure. The vacuum expectation value 〈A〉 of the physical scalar field is linearly divergent, while 〈F〉=0. This divergence is canceled by a counterterm in the superpotential which is linear in A. The divergences of two-point functions agree with the nonrenormalization theorems of the flat-space model. However, the divergent one-point function shows that the special notion of ``naturalness'' in flat-space supersymmetry does not extend to (AdS${)}_{4}$.
Specifying Links Between Executive Functioning and Theory of Mind during Middle Childhood: Cognitive Flexibility Predicts Social Understanding

The purpose of this study was to specify the development of and links between executive functioning and theory of mind during middle childhood. One hundred four 7- to 12-year-old children completed a battery of age-appropriate tasks measuring working memory, inhibition, flexibility, theory of mind, and vocabulary. As expected, spatial working memory and flexibility increased significantly with age, especially after 7 years. Moreover, flexibility predicted social understanding over and above the effects of age, vocabulary, working memory, and inhibition. Together, these findings highlight improvements in and tight relations between complex aspects of executive functioning and theory of mind during middle childhood and suggest that executive functioning and theory of mind are linked beyond their emergence in early childhood.
Regulation of the human interleukin-2 receptor α chain promoter: Activation of a nonfunctional promoter by the transactivator gene of HTLV-I

Abstract We have characterized regulatory regions of the human IL-2 receptor alpha chain (IL2Rα) promoter. 5′ deletion constructs extending to −327 directed CAT expression in HTLV-I-infected T cells, which express IL2Rα constitutively, and in Jurkat cells, which express IL2Rα only after induction. Deletions to −267 and −265 were active only in HTLV-I-transformed T cells, but their activity in Jurkat cells was restored by cotransfection of a construct expressing the HTLV-I transactivator protein (tat-I). However, HTLV-I-infected human osteosarcoma cells do not express IL2Rα-CAT constructs. Thus cell-type-specific factors are required for IL2Rα expression, and direct or indirect interaction(s) between tat-I and a specific region of the IL2Rα promoter may cause altered regulation. Tat-I also augments IL2-CAT expression under some conditions, suggesting possible autocrine or paracrine mechanisms for HTLV-I-induced leukemogenesis.
Cardiovascular effects of and interaction between calcium blocking drugs and anesthetics in chronically instrumented dogs. V. Role of pharmacokinetics and the autonomic nervous system in the interactions between verapamil and inhalational anesthetics.

To assess the role of both pharmacokinetics and the autonomic nervous system in the interaction between inhalational anesthetics and verapamil, dogs were chronically instrumented to measure heart rate, PR interval, dP/dt, cardiac output, and aortic blood pressure. In a first group of seven dogs, studied awake and during halothane (1.2%), enflurane (2.5%), and isoflurane anesthesia (1.6%), verapamil was infused for 30 min in doses calculated to obtain similar plasma concentrations (83 +/- 10, 82 +/- 6, 81 +/- 10, and 77 +/- 9 ng.ml-1, respectively). For the latter purpose, the infusion dose was 3 and 2 micrograms.kg-1.min-1 awake and during anesthesia, respectively, preceded by a loading dose of 200, 150, and 100 micrograms.kg-1, awake, during isoflurane, and halothane and enflurane, respectively. In awake dogs, verapamil induced an increase in heart rate (24 +/- 5 bpm) and PR interval (35 +/- 9 msec) and a decrease in mean arterial pressure (-5 +/- 2 mmHg) and dP/dt (-494 +/- 116 mmHg/s). Although plasma concentrations were similar in awake and in anesthetized dogs, the only statistically significant changes induced by verapamil were an increase in heart rate and a decrease in dP/dt during halothane and enflurane, while left atrial pressure increased only with enflurane. In a second group of six dogs, verapamil pharmacokinetics were determined in the presence and absence of a ganglionic blocking drug (chlorisondamine, 2 mg.kg-1 iv). Blockade of ganglionic transmission resulted in a decrease in both initial volume of distribution and total clearance of verapamil--changes similar to those previously reported with inhalational anesthetics.(ABSTRACT TRUNCATED AT 250 WORDS)
HYBRID ZERO ENERGY HOUSES (ZEH) FOR FLORIDA'S HOT, HUMID CLIMATE

The building sector is responsible for a large percentage of the energy usage in the United States as a whole and Florida’s buildings consume more energy than those in any other state in the country. Florida’s hot humid climate presents challenges for the implementation and maintenance of energy effi cient buildings but also offers opportunities to reduce building energy usage. Building technology has improved dramatically in recent years and photovoltaic technology has become affordable for individual site based generation of clean renewable energy making the dream of net zero energy houses [ZEH] a reality. After a brief history of energy effi cient buildings in the United States, this paper discusses passive design strategies in Florida, advancements that have been made toward ZEH, and several cutting edge technologies that hold promise for the Florida ZEH of the future. This paper argues that although signifi cant steps have been made toward their implementation, ZEH examples to date have not taken full advantage of Florida’s mild climate. The author maintains that Florida ZEH can be designed to take advantage of the mild seasons as well as buffer against the seasons of severe heat and humidity with a hybrid open/closed building type that can improve on the advancements already made in ZEH design while promoting a comfortable, healthy indoor/outdoor lifestyle for Florida residents.
Direct in vivo evidence demonstrating neointimal migration of adventitial fibroblasts after balloon injury of rat carotid arteries

Background—Clinical and experimental evidence suggest that the adventitia participates in the response to endoluminal vascular injury. The current study used a direct approach to test the hypothesis that, after balloon injury of the rat carotid artery, adventitial fibroblasts migrate in a luminal direction and contribute to neointima formation. Methods and Results—Primary syngeneic adventitial fibroblasts were stably transduced with retroviral particles coordinating expression of β-galactosidase (LacZ) and introduced into the adventitia of right carotid arteries of rats immediately after balloon injury. At defined times after injury and fibroblast implantation, rats were euthanized, and arterial tissue was examined for detection of LacZ mRNA (reverse transcription polymerase chain reaction), DNA (polymerase chain reaction), and in situ enzymatic activity. LacZ expression was detected in the media 5 days postinjury and in both media and neointima at 7, 10, and 14 days postinjury. LacZ was undetectable in i...
Optimum bit and energy resources allocation and lifetime maximzation for portable video communication devices

We consider a portable video device which captures and compresses video data. The compressed bit stream is either stored in an on-board storage device or transmitted to a remote user through wireless channels. The storage space or the amount of energy and channel bandwidth available for data transmission determines the total number of bits that the video encoder can generate. Besides this bit resource constraint, the portable video device also operates under data processing energy constraint. This is because video compression is computationally intensive and energy-consuming. One of the central challenging issues in portable video communication system design is how to maximize the operational lifetime. In this work, we will investigate the following research problem: given a portable device, which has a certain amount of power supply E and the maximum number of bits it can store or transmit is R , and the required video quality level is D , what is the maximum operational lifetime of this portable device, and how to allocate the bit and energy resources to achieve this maximum lifetime? To address this problem, we design an energy-scalable video encoder and study its power-rate-distortion (P-R-D) behavior. We theoretically study the optimum bit and energy resource allocation and analyze the energy saving performance. Our results show that for typical consumer electronic videos, using the proposed P-R-D video encoding technology, the operational lifetime of the portable device can be doubled or even tripled. This has a significant impact in energy-efficient portable video communication system design.
Dither-free method for phase-mirror control in optical-feedback stabilized diode laser systems

Abstract A new, straightforward method of stabilizing the diode-cavity pathlength for optical-feedback locked diode laser systems is described. The technique uses the spatial mode patterns excited in the coupled confocal resonator to derive an error signal for the feedback phase. The theoretical basis for the method is described together with its experimental realization for a 674 nm visible diode laser system. Included in this study are linewidth and frequency stability measurements of the beat frequency between two identical but independent systems.
Peroxyglutaryl nitrate: Formation and infrared spectrum

Abstract Infrared studies of irradiated ppm mixtures of glutaraldehyde, Cl2 and NO2 in air have shown that one of the photo-oxidation products is peroxyglutaryl nitrate (PGN). The infrared spectrum and absolute intensities of PGN absorption bands were measured and compared to those of other peroxyacyl nitrates. In the atmosphere, PGN may be formed by the reaction of OH with glutaraldehyde in the presence of NO2.
Spontaneous sustained ventricular tachycardia in the Electrophysiologic Study Versus Electrocardiographic Monitoring (ESVEM) trial

AbstractObjectives. We compared the QRS waveforms of the initial and subsequent complexes of spontaneous sustained monomorphic ventricular tachycardia and the rhythm induced at electrophysiologic s...
Sense Making across Disciplines: The Spindlers, Adaptation, and the Self That Never Left

The Psychoanalytic Study of Society, Volume 17: Essays in Honor of George D. and Louise S. Spindler Edited by L. Bryce Boyer and Ruth Boyer
MUSSELS DEVELOPING UNDER PRESSURE: COLD IS THE KEY

![Figure][1] It is a hard life for a mussel in the deep sea. Temperatures are always a chilly 4°C or cooler, food is scarce or patchy at best, not to mention the hydrostatic pressure of thousands of meters of water constantly pressing on you. If you can't stand the cold, there is one other
An anomalous behavior in low-frequency GaAs resistor noise

Abstract This paper presents low-frequency noise found in an implanted GaAs resistor. An anomalous slope was found to be relatively constant over a two decade frequency span. This indicates the presence of a noise source for which there is no known model.
The click modular router

Clicks is a new software architecture for building flexible and configurable routers. A Click router is assembled from packet processing modules called elements. Individual elements implement simple router functions like packet classification, queuing, scheduling, and interfacing with network devices. A router configurable is a directed graph with elements at the vertices; packets flow along the edges of the graph. Several features make individual elements more powerful and complex configurations easier to write, including pull connections, which model packet flow drivn by transmitting hardware devices, and flow-based router context, which helps an element locate other interesting elements. Click configurations are modular and easy to extend. A standards-compliant Click IP router has 16 elements on its forwarding path; some of its elements are also useful in Ethernet switches and IP tunnelling configurations. Extending the IP router to support dropping policies, fairness among flows, or Differentiated Services simply requires adding a couple of element at the right place. On conventional PC hardware, the Click IP router achieves a maximum loss-free forwarding rate of 333,000 64-byte packets per second, demonstrating that Click's modular and flexible architecture is compatible with good performance.
Shear strain-induced changes in liquid crystal alignment monitored by planar array infrared spectroscopy

Planar array infrared (PAIR) spectroscopy was applied to the study of the orientational motions of liquid crystals (LCs) under the influence of shear strain. Due to the ability to simultaneously monitor spectral bands corresponding to transition moments oriented along different directions along the molecular axes, it is possible to unambiguously determine the motion of the nematic director under the influence of external stimuli. Unlike previous attempts at spectroscopic studies of shear-induced liquid crystal orientation, PAIR is able to study the samples in real time, without the need to continuously subject the samples to cyclic perturbation. Of the three classical geometries employed in the rheological study of LCs, it was found that only one produced a measurable spectroscopic signal. This geometry was further explored by constant shear rate experiments over a range of shear rates and by exposing the samples to electric fields of varying strengths during shearing. The results obtained were seen to agree qualitatively with theoretical predictions.
A novel Whole Air Sample Profiler (WASP) for the quantification of volatile organic compounds in the boundary layer

Abstract. The emission and fate of reactive volatile organic compounds (VOCs) is of inherent interest to those studying chemical biosphere–atmosphere interactions. In-canopy VOC observations are obtainable using tower-based samplers, but the lack of suitable sampling systems for the full boundary layer has limited the availability of data characterizing the vertical structure of such gases above the canopy height and still in the boundary layer. This is an important region where many reactive VOCs are oxidized or otherwise removed. Here we describe an airborne sampling system designed to collect a vertical profile of air into a 3/8 in. OD (outer diameter) tube 150 m in length. The inlet ram air pressure is used to flow sampled air through the tube, which results in a varying flow rate based on aircraft speed and altitude. Since aircraft velocity decreases during ascent, it is necessary to account for the variable flow rate into the tube. This is accomplished using a reference gas that is pulsed into the air stream so that the precise altitude of the collected air can be reconstructed post-collection. The pulsed injections are also used to determine any significant effect from diffusion/mixing within the sampling tube, either during collection or subsequent extraction for gas analysis. This system has been successfully deployed, and we show some measured vertical profiles of isoprene and its oxidation products methacrolein and methyl vinyl ketone from a mixed canopy near Columbia, Missouri.
Quantitative Auger analysis of complex electrical contact alloy materials

Abstract Addition of elemental Auger spectra has been used to produced several series of Auger lineshapes versus composition for the ovelapping peaks resulting from mixtures of Cu, Pt, Pd or Ag in Au; S in Au or Pt, Cl in Au, Pt or Pd; C (both graphitic and carbidic) in Au, Pt, Ag or Pd. These assorted lineshapes series may be used to obtain semi-quantitative analysis of overlapping peaks by matching lineshapes, but have also been used to calibrate peak ratios versus composition in order to quantitatively separate contributions to overlapping Auger peaks. This procedure is illustrated by application to the quantitative analysis of tw electrical contact alloys - ASTM B541. Advantages and limitations of this procedure are B540 and ASTM B541. Advantages and limitations of this procedure are discussed.
Apple Anthocyanins: Identification of Cyanidin‐7‐Arabinoside

SUMMARY— The anthocyanin pigments of Red Delicious apples were isolated and identified from their chromatographic, spectral and chemical properties. The maior pigment was cyanidin-3-galactoside. The minor pigments were cyanidin-3-arabinoside and cyanidin-7-arabinoside. Cyanidin-7-arabino-side was isolated from a natural source for the first time. Three pigments were isolated from 74 varieties of apples, two from six varieties and only one from two varieties.
A comparison of the dissolution profiles for several commercially available [131I]sodium iodide capsules

Abstract The dissolution profiles for [ 131 I]sodium iodide diagnostic capsules from three commercial vendors were studied. The 131 I release rate in water was rapid for capsules from Vendors A and C. The dissolution profile for the Vendor B product resembled that of a sustained release capsule. The data from the study indicates the potential for differences in the bioavailability of 131 I from the sodium iodide diagnostic capsules.
Prenatal cocaine and/or nicotine exposure in rats: Preliminary findings on long-term cognitive outcome and genital development at birth

Prenatal cocaine or nicotine exposure is associated with a variety of teratogenic effects. The current study was conducted to determine their effects alone and in combination on cognitive function and sexual differentiation. Pregnant Long-Evans rats (N = 19) were exposed to either cocaine (15 mg/kg/dose b.i.d. SC on GD 8-20); nicotine (4 mg/kg/day continuous SC infusion on GD 4-20); both nicotine + cocaine; or vehicle only. Birth weight and anogenital distance (AGD) were measured in all pups at birth. Learning and memory were tested in the Morris water maze (MWM) during prepubertal and pubertal ages in five daily consecutive sessions and a sixth session 1 week later and in the radial-arm maze (RAM) during adulthood. In the RAM, a drug challenge of the beta-noradrenergic antagonist propranolol (10-20 mg/kg) was given after acquisition training. Maternal weight gain was reduced 13-42% and offspring birth weight was reduced by 7-12% in all three exposure groups compared to controls. Cocaine decreased the AGD of males (2.68 mm) compared to 2.88 mm in noncocaine-exposed male pups (p < 0.025). A sex-selective cocaine effect was also seen after adjustment of AGD measurements for body weight. With this measure cocaine-treated females showed significantly (p < 0.05) greater AGD than those not exposed to cocaine. In the MWM, there were two types of trials: cued reference memory trials and uncued spatial working memory trials. On cued reference memory trials significant cocaine-induced latency deficits were seen on only the first session. On spatial working memory trials cocaine-induced latency deficits were seen throughout daily training on sessions 1-5, but not the retention session 6, 1 week later. During RAM acquisition, there were no significant differences in choice accuracy between exposure groups. Following propranolol challenge, deficits in choice accuracy were demonstrated in rats prenatally exposed to cocaine or nicotine. These rats did not show any response to propranolol, whereas the controls slightly improved their choice accuracy. The results of this study indicated that prenatal cocaine exposure altered long-term cognitive function under basal conditions in the MWM and drug challenge in the RAM, birth weight, and genital development. Cocaine-induced cognitive deficits were predominately in working memory rather than reference memory or long-term retention. Prenatal nicotine exposure was only observed to alter birth weight and cognitive function in response to propranolol challenge in the RAM.
Material and Reliability Considerations for Anisotropically Conductive Adhesive Based Interconnects

An adhesive based interconnect design in which the contact force between a bumped die and substrate is maintained by the shrinkage stress of the adhesive was investigated for use in high performance applications. In general, heating will reduce the contact force because of the differential thermal expansions and load relaxation in the adhesive. Special experimental techniques have been developed to measure the relevant materials properties. The potential for optimization in terms of materials selection is discussed.
Abolition and Imperial Law, 1790-1820

Historians have represented the movement for the abolition of the slave trade as a turning point in international law, either characterising the formation of mixed commissions to adjudicate slave ship captures as elements of early human rights law or interpreting the treaty regime supporting the ban on the slave trade as marking a decisive shift towards positivism in international law. A closer look at the legal history of abolition suggests that such perspectives omit an important dimension: the ties between abolition and imperial legal consolidation. In exploring such ties, the article first examines prize law and its direct and indirect influence on calls for intra-imperial regulation of the slave trade, especially its effective criminalisation. Across the empire, efforts to ban the slave trade reflected and reinforced pressures to strengthen imperial legal authority by regulating and restricting planter legal prerogatives.
Temperature dependence of the dark current and activation energy at avalanche onset of GaN avalanche photodiodes

We report a study of the performance of an avalanche photodiode (APD) as a function of temperature from 564 K to 74 K. The dark current at avalanche onset decreases from 564 K to 74 K by approximately a factor of 125 and from 300 K to 74K the dark current at avalanche offset is reduced by a factor of about 10. The drop would have been considerably larger if the activation energy at avalanche onset (Ea) did not also decrease with decreasing temperature. These data give us insights into how to improve the single-photon counting performance of a GaN based ADP.
A probabilistic Bayesian framework for progressively updating site-specific recommendations

The goal of this research was to create an agricultural adaptive management framework that enables the probabilistic optimization of N fertilizer to achieve maximized net returns under multiple uncertainties. These uncertainties come in the form of bioclimatic variables that drive crop yield, and economic variables that determine profitability. Taking advantage of variable rate application (VRA), spatial monitoring technologies, and historical datasets, we demonstrate a comprehensive spatiotemporal modeling approach that can achieve optimal efficiency for the producer under such uncertainties. The utility of VRA fertilizer research for producers is dependent upon a localized accurate understanding of crop responses under a range of possible climatic regimes. We propose an optimization framework that continuously updates by integrating annual on-site experiments, VRA prescriptions, crop prices received, input prices, and climatic conditions observed each year under a dryland spring wheat (Triticum aestivum) cropping system. The spatio-temporal Bayesian framework used to assimilate these data sources also enables calculation of the probabilities of economic returns and the risks associated with different VRA strategies. The results from our simulation experiments indicated that our framework can successfully arrive at optimum N management within 6–8 years using sequential Bayesian analysis, given complete uncertainty in water as a driver of crop yield. Once optimized, the spatial N management approach increased net returns by $23–25 ha−1 over that of uniform N management. By identifying small-scale targeted treatments that can be merged with VRA prescriptions, our framework ensures continuous reductions in parameter uncertainty. Thus we have demonstrated a useful decision aid framework that can empower agricultural producers with site-specific management that fully accounts for the range of possible conditions farmers must face.
Some mathematical aspects of flame chaos and flame multiplicity

Abstract In these review lectures, we survey recent mathematical results on the low, finite-dimensional behavior of the Kuramoto-Sivashinsky equations; the latter model thermo-diffusive flame front instabilities. We outline how these PDE's are rigorously equivalent to a finite dynamical system (ongoing joint work with C. Foias, G. Sell, R. Temam). We also present an introduction to multiplicity phenomena in flames caused by chemical kinetics (the latter is an ongoing joint work with P. Clavin and P.C. Fife).
Is genetic information irreducible

In his 1992 book Natural Selection: Domains, Levels, and Challenges, George C. Williams stated that organisms consist of two separate domains, which Williams called the "material" and the "codical." The former is the domain of chemistry, including particularly the nucleotides of DNA and their chemical components. The codical domain consists of non-material information. The information encoded in DNA is fundamentally distinct from the chemical medium in which the information is recorded, just as the information conveyed in a book is fundamentally distinct from the ink and paper on which it is printed. Williams explicitly invoked this analogy between biology and literature:
Synthetic atmospheric transmittance spectra near 15 and 4.3μm

Abstract Synthetic monochromatic atmospheric transmittance spectra are presented for infrared intervals in the vicinity of the 15 and 4.3μm CO2 bands. The intervals are nominally 20 cm-1 in width, and the spectra partition the intervals [560, 780] cm-1 and [2180, 2400] cm-1, respectively. The spectra are for a vertical atmospheric path. A given spectrum is presented at that pressure for which the mean weighting function (-d Tau (P) ⧸d ln P) is a maximum. In order to indicate the molecular origin of the features in a given spectrum, separate spectra are also presented for those species which make center line contributions to the absorption over the interval. The transmittance model for the calculations is described. In addition to the representation of spectral features for intervals which comprise these two CO2 bands, the spectra afford a utility in the design of high precision satellite temperature radiometers.
The Romanian Battlefront in World War I

During the summer of 1918, German and Habsburg officials in occupied Wallachia perceived an unusual problem: officers in the Romanian army had returned to their homes in Wallachia after accepting t...
What is the proper experimental unit for long-term rodent studies? An examination of the NTP benzyl acetate study

The National Toxicology Program (NTP) rat bioassay on benzyl acetate shows an apparent increase in acinar-cell adenomas of the pancreas in male rats [1]. The statistical significance of the apparent trend is examined using the animal, cage, or rack/shelf location as the statistical independent experimental (sampling) unit. Experimental, statistical, and empirical considerations indicate that, in this experiment, if there is a proper experimental unit, it is the shelf of animals on a rack rather than the individual animal or cage of animals. Using the shelf as the experimental unit, the apparent increase in acinar-cell adenomas is not statistically significant. There is strong evidence for pancreatic tumor rates to differ among shelves which implies that toxicologists should consider cage randomization.
The mechanism of aberration in late atrioventricular junctional beats

Abstract There are 2 kinds of atrioventricular (A-V) junctional extrasystoles with aberrant conduction: early premature beats where the aberration is due to refractoriness of the ventricular myocardium, and late premature beats or escape beats where this mechanism seems improbable because of the long QRS coupling interval. To explain the aberrant conduction in this latter group there are 3 prevailing hypotheses: (1) A-V junctional beats reaching the ventricles by means of preferential conduction within the His bundle; (2) conduction of the A-V junctional beat to the ventricles through paraspecific (Mahaim) fibers; and (3) low intracellular electrical potential due to slow diastolic depolarization in some ventricular automatic cells. Because such cells may conduct abnormally, this may explain the altered (aberrant) configuration of A-V junctional escape beats on the basis of abnormal function without necessarily invoking anatomic aberrant pathways. In earlier publications, we postulated the existence of a single, synchronized and highly organized impulse-producing and conducting system for the heart (synchronized sinoventricular conduction). This concept included preferential longitudinal conduction as a normal phenomenon in the entire A-V junctional area. In this report we suggest, on the basis of clinical electrocardiographic examples, that A-V junctional beats produce ventricular aberration by a desynchronization of the normal sequence of depolarization in the A-V junctional area and its distal branches, except when the ectopic junctional focus is fortuitously located directly on the axis of normal depolarization. In accordance with these views we further postulate the existence of graded degrees of ventricular fusion beats when 2 active supraventricular stimuli (sinus and A-V junctional) produce 2 parallel competing and dynamically changing depolarization fronts in the ventricles. Such serial fusion beats may be recognized by a shortening of the P-R interval concomitant with changes in the configuration of the QRS complex, which consequently exhibits features of both the sinus and the aberrant (junctional) QRS patterns.
Electron-impact ionization of Mg-like ions: S4+, Cl5+, and Ar6+

Absolute electron-impact ionization cross sections were measured as a function of collision energy for ions in the Mg-isoelectronic sequence ${\mathrm{S}}^{4+}$, ${\mathrm{Cl}}^{5+}$, and ${\mathrm{Ar}}^{6+}$. The measurements cover the energy range from threshold to 1500 eV and show onsets due to the indirect ionization process of inner-shell excitation followed by autoionization. The relative magnitude of the indirect ionization process increases dramatically in comparison with the direct process along the sequence, a feature which is also emphasized by earlier data for ${\mathrm{Al}}^{+}$.
Cell-Seeded Tubularized Scaffolds for Reconstruction of Long Urethral Defects: A Preclinical Study

Background The treatment options for patients requiring repair of a long segment of the urethra are limited by the availability of autologous tissues. We previously reported that acellular collagen-based tubularized constructs seeded with cells are able to repair small urethral defects in a rabbit model.
Development of avian intrapulmonary chemoreceptors.

Abstract Although avian intrapulmonary chemoreceptors (IPC) have been studied extensively in adults, the maturation of IPC CO 2 sensitivity during development is completely unknown. To begin investigating IPC development we asked two fundamental questions: (1) Are IPC capable of sensing CO 2 during early development, and, if so, how early? And, (2) does IPC CO 2 sensitivity during early development exhibit postnatal maturation compared to IPC discharge characteristics in adult ducks? We addressed these questions by recording from single IPC Anas platyrhynchos ducklings beginning approximately 6 h prior to internal pipping through 4 days of postnatal development. We then compared mean IPC discharge characteristics during early development with mean IPC activity from adult ducks greater than 12 weeks old. In total, we recorded 28 individual IPC from 5 ducklings and 12 adult ducks. Results show that IPC were capable of responding to rapid step changes in CO 2 before hatching occurred, during the paranatal developmental period. We also found that mean IPC activity during early development had increased peak discharge frequencies, greater spike frequency adaptation, and less tonic CO 2 sensitivity when compared to adults ( P ≤ 0.05). These results suggest that during early development phasic IPC CO 2 sensitivity is fully developed, yet tonic IPC CO 2 sensitivity exhibits postnatal maturation possibly associated with hatching. These results also suggest that the mechanisms that underlie phasic and tonic IPC action potential discharge, and therefore the degree of partial spike frequency adaptation, may be independent processes with different developmental trajectories.
Analysis of the Orthogonal Electrocardiogram and Vectorcardiogram in Ventricular Conduction Defects With and Without Myocardial Infarction

Correlations were computed for 320 electrocardiographic measurements and variables of ventricular conduction defects in 452 unselected patients. The variables consisted of right and left ventricular conduction defects with and without myocardial infarction. Quantitative criteria were established which led to the identification of infarction in the presence of a ventricular conduction defect. The data were analyzed by two methods: (1) using four independent measurements, and (2) discriminant function analysis in conjunction with a likelihood ratio test using 9 or 10 measurements. Both techniques yielded similar results. In the presence of left ventricular conduction defects 52% of the cases of infarction were identified with a 14% false positive diagnosis of infarction. In the cases of right ventricular conduction defects the results were 54% and 11%, respectively. In both, the sensitivity could be increased at the expense of an increase in the false positive frequency. This study confirms the difficulties...
Headaches in patients with transient ischemic attacks.

SYNOPSIS Thirty-four patients with transient ischemic attacks (TIA) have been followed for 1 to 24 months. Twenty-two patients had TIA in the anterior and 12 in the posterior circulation. Episodic and late onset vascular headaches occurred. Four patients had episodic headaches, 7 patients had late onset vascular headaches and 11 patients had both types of headaches. Episodic headaches preceded, occurred during, or immediately after TIA. These headaches were present in 15 of the patients (44%). Late onset vascular headaches started in middle or late life, occurred independently of TIA and were observed in 18 patients (52.9%). In 13 patients the headaches began 1 month to 15 years prior to TIA and in 5 cases, 2 days to 1year after the onset of TIA. Late onset vascular headaches preceded TIA in 38.2% of patients. These headaches might be of prognostic significance in some patients for the development of TIA and stroke.
Differences in Perceptions of Barriers to College Enrollment and the Completion of a Degree Among Latinos in the United States

This study examined the differences in perceptions of barriers in education among Latinos in the United States based on the level of linguistic acculturation, generational status, academic achievement, and socioeconomic status of the participants. This study used data from the Pew Hispanic Research Center. Results indicated that later-generation participants with high levels of linguistic acculturation, high socioeconomic status, and high academic achievement perceived greater barriers to enrollment in college and the completion of a degree.
Vacuum deposition of chiral sculptured thin films with high optical activity

We present the technique of bideposition to realize thin-film helicoidal bianisotropic mediums (TFHBM’s) that exhibit high optical activity. We show, by experiment as well as by simulation, that the optical rotation produced by these chiral sculptured thin films is roughly proportional to the square of the local linear birefringence. Experimental measurements on bideposited TFHBM’s of titanium oxide yield a typical value of 5°/µm for the effective specific rotation in the short-wavelength regime; the corresponding value determined for the standard unideposited TFHBM’s is 1°/µm. Both types of TFHBM’s are highly optically active in comparison with quartz, fluorite films, and cholesteric liquid crystals. Bideposited TFHBM’s will lend themselves to many different types of optical devices.
Individuality and mutuality in the language of families of field-dependent and field-independent children.

Abstract The use of singular and plural first-person pronouns provided a measure of individuality and mutuality in families of 18 field-dependent and 20 field-independent children (19 boys and 19 girls). The families were observed in home and laboratory settings. Consistent with notions of a more differentiated sense of self, field-independent boys and girls used more 1 words; the greater social orientation of the field-dependent children was reflected in their more frequent use of we terms. Family members in the field-independent group were more varied in their use of these linguistic measures, especially in the lab. Fathers of field-independent children used more we words. These usages were discussed in terms of social control mechanisms. Personal pronoun usage as indicators of separateness/connectedness in families was also discussed.
Investigation of phosphoserine and cytidine 5'-phosphate by heteronuclear two-dimensional spectroscopy: samples with strong proton coupling

Abstract Heteronuclear two-dimensional magnetic resonance is a novel method for investigating the conformations of cellular phosphates. The two-dimensional proton spectra are detected indirectly via the phosphorus-31 nucleus and thus allow determination of proton chemical shifts and coupling constants in situations in which the normal proton spectrum is obscured. Previous investigations of cellular phosphates with relatively simple spin systems have shown that the two-dimensional proton spectrum can be readily related to the normal proton spectrum by subspectral analysis. The normal proton spectrum can be decomposed into two subspectra, one for each polarization of the phosphorus-31 nucleus. The two-dimensional spectrum arises from the difference between the subspectra, and the normal proton spectrum is the sum. This allows simulation of the two-dimensional spectra and hence determination of the proton chemical shifts and coupling constants. Many cellular phosphates of interest, such as 5′-nucleotides and phosphoserine, contain three protons coupled to the phosphorus which are strongly coupled to one another. These samples are amenable to the two-dimensional method and the straightforward subspectral analysis is preserved when a 90° pulse is applied to the protons in the magnetization transfer step. The two-dimensional proton spectra of the samples investigated here have higher resolution than the normal proton spectra, revealing spectral features not readily apparent in the normal proton spectra.
Hexadecyl-functionalized lamellar mesostructured silicates and aluminosilicates designed for polymer–clay nanocomposites. Part I. Clay synthesis and structure

Abstract Motivated by a need for synthetic clays that can be dispersed and exfoliated in polymer melts without added compatibilizers, lamellar mesostructured silicates and aluminosilicates with covalently attached hexadecyl functional groups (C 16 -LMS and C 16 -LMAS, respectively) were prepared by sol–gel syntheses and their structures were characterized. Based on XRD and TEM data, lamellar products with layer spacings of 4.8–4.9 nm were obtained between room temperature and 60 °C (C 16 -LMS) or 70 °C (C 16 -LMAS). The degree of condensation of the aluminosilicate layers increased at the higher synthesis temperatures. Attachment of organic groups to the inorganic sheets was confirmed by 29 Si solid state MAS NMR and IR spectroscopy. The sheets of C 16 -LMS consisted of single or double layers of tetrahedral silicate groups, each attached to a hexadecyl chain. C 16 -LMAS was composed of pyrophyllite-like layers (Si:Al=2) with an octahedral aluminum layer sandwiched between two tetrahedral silicate layers and hexadecyl surface groups. Tetrahedral aluminum sites were also present. The clay layer spacing could be increased to 5.2 nm by addition of tetraethoxysilanes during the synthesis (C 16 -SiO 2 -LMAS). C 16 -SiO 2 -LMAS was structurally similar to C 16 -LMAS; however, the presence of additional silicate groups in this structure increased the inorganic layer thickness and introduced further structural disorder.
The Political Economy of Medical Care An Explanation of the Composition, Nature, and Functions of the Present Health Sector of the United States

This presentation provides an alternative explanation of the present composition, nature, and functions of the health sector in the United States to those frequently given in sociological, economic, and medical care literature. These expalantions usually maintain that the Amcerican health sector is a result of the value system of the assumedly middle class American society. In this presentation it is postulated that the present economic structure of the United States determines and maintains a social class structure, both outside and within the health sector, and that the different degrees of ownership, control, and influence that these classes have on the means of production, reproduction, and legitimization in the United States explain the composition, nature, and functions of the health sector. It is further postulated that the value system is not the cuase, but a sysmptom, of these class controls and influences. The paper is divided into three sections. The first part profices a description of the class structure, which includes the corporate class, upper middle class, lower middle class, and working class, and it describes the mechanisms whereby this structure is maintained and replicated, both outside and within the health sector. The second section analyzes: (1)the production characteristics and social make-up of the thre main sectors of the U. S. economy-the monpolistic, state, and competitive sectors-and it focuses especially on the monopolistic sector, which is assumed to be the dominant sector in the U. S. economy, with its needs determining to a large degree the functions of the social sectors, including those of the health sector; (2) the increasing dominance of the monopolistic sector in the health sector, by means of the financial institutions, which conflicts primarily with the providers'relative control of the financing of health services; and (3) the main conflict in the control of the reproductive (academic) an distributive (delivery) institutions which, it is postulated, is not, as is generally belived, between the providers and the so-called consumers, but rather between the corporate and upper middle classes (including the providers), who control those institutions, and the majority of the U. S. population, the lower middle and working classes, who do not control them...
Folate receptor targeting silica nanoparticle probe for two-photon fluorescence bioimaging

Narrow dispersity organically modified silica nanoparticles (SiNPs), diameter ~30 nm, entrapping a hydrophobic two-photon absorbing fluorenyl dye, were synthesized by hydrolysis of triethoxyvinylsilane and (3-aminopropyl)triethoxysilane in the nonpolar core of Aerosol-OT micelles. The surface of the SiNPs were functionalized with folic acid, to specifically deliver the probe to folate receptor (FR) over-expressing Hela cells, making these folate two-photon dye-doped SiNPs potential candidates as probes for two-photon fluorescence microscopy (2PFM) bioimaging. In vitro studies using FR over-expressing Hela cells and low FR expressing MG63 cells demonstrated specific cellular uptake of the functionalized nanoparticles. One-photon fluorescence microscopy (1PFM) imaging, 2PFM imaging, and two-photon fluorescence lifetime microscopy (2P-FLIM) imaging of Hela cells incubated with folate-modified two-photon dye-doped SiNPs were demonstrated.
Prospective associations between inflammatory and hemostatic markers and physical functioning limitations in mid-life women: Longitudinal results of the Study of Women's Health Across the Nation (SWAN)

Background Due to the public health burden of age-related declines in physical functioning, it is important to identify targets for intervention for the prevention of functional decline. We prospectively examined whether higher levels of inflammatory and hemostatic markers (high-sensitivity C-reactive protein (hs-CRP), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator antigen (tPA-ag), fibrinogen, and Factor VIIc (FVIIc)) were prospectively associated with reporting greater limitations in perceived physical functioning, and explored potential racial differences in the associations, in a multi-ethnic sample of mid-life women.