cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of hypoxia on the expression of pro- and anti-apoptotic proteins in neuronal nuclei of the guinea pig fetus during gestation.

The present study investigates the expression of apoptotic proteins Bax, Bad, Bcl-2, and Bcl-xl following hypoxia in the cerebral cortex of the guinea pig fetus as a function of gestational age. Normoxic (Nx, n = 6) and hypoxic (Hx, n = 6) guinea pig fetuses at 35 and 60 days gestation were studied. Bax expression (OD X mm2) was 96.9 ± 9.5 (Nx 35 days), 116.5 ± 8.3 (Hx 35 days), P < 0.05 and 116.2 ± 3.4 (Nx 60 days, 144.6 ± 11.7 (Hx 60 days), P < 0.05. Bad expression (OD X mm2) was 78.6 ± 2.6 (Nx 35 days), 102.9 ± 5.8 (Hx 35 days), P < 0.05 and 101.5 ± 4.3 (Nx 60 days), 139.8 ± 7.9 (Hx 60 days), P < 0.05 vs. Nx 60 days, also significantly higher from preterm hypoxia P < 0.007. Expression of Bcl-2 (OD X mm2) was 27.4 ± 2.0 (Nx 35 days), 28.0 ± 2.4 (Hx 35 days), and 27.4 ± 2.7 (Nx 60 days), 29.7 ± 2.3 (Hx 60 days). Expression of Bcl-xl (OD X mm2) was 51.0 ± 4.4 (Nx 35 days), 46.1 ± 8.0 (Hx 35 days) and 50.0 ± 1.4 (Nx 60 days), 54.9 ± 7.4 (Hx 60 days). Hypoxia resulted in increased expression of the proapoptotic proteins Bax and Bad by 20% and 30% in the preterm as compared to 24% and 38% at term, without altering the expression of anti-apoptotic proteins Bcl-2 and Bcl-xl. We conclude that the hypoxia-induced increased expression of Bax and Bad is greater at term compared to preterm. Furthermore, the hypoxia-induced increase in proapoptotic as compared to antiapoptotic proteins at term will accelerate the ongoing active process of programmed cell death at term compared to preterm gestation.
When 'Don't' means'Do': pragmatic and cognitive development in understanding an indirect imperative

The study describes the sequence through which children pass between the ages of two and six as they become able to draw an inference about the speaker's intentions and to apply a pragmatic discour...
Effect of components of acid-hydrolysed hardwood on conversion of d-xylose to 2,3-butanediol by Klebsiella pneumoniae

Abstract The effects of selected components of acid-hydrolysed hardwood (hydrolysate) on growth, sugar utilization, and 2,3-butanediol (BDO) production by a strain of Klebsiella pneumoniae isolated from cellulosic waste were investigated. Acetate, sulfate, furfural, and phenolic compounds were evaluated as potential microbial inhibitors commonly present in hydrolysate. Depending on the inoculation level, yields of BDO were stimulated by acetate levels up to 1.6% (w/v). Sulfate levels up to 0.2% (w/v) did not affect growth, but reduced the BDO yield by approximately 30%. Similar growth results were obtained with furfural concentrations up to 0.2% (w/v), but BDO yields were slightly higher. Phenolic compounds (syringealdehyde and vanillin) were the most growth inhibitory of the potential inhibitors evaluated. Growth was inhibited by concentrations of 0.10% (w/v), while concentrations as low as 0.05% (w/v) inhibited BDO production.
Beaver dams maintain fish biodiversity by increasing habitat heterogeneity throughout a low-gradient stream network

Summary Understanding the relationship between heterogeneity and biodiversity is an active focus of ecological research. Although habitat heterogeneity is conceptually linked to biodiversity, the amount and configuration of heterogeneity that maintains biodiversity within ecosystems is not well understood, especially for an entire stream network. Here, we tested alternative outcomes about how habitat alterations caused by beaver dams affected native fish biodiversity. Specifically, we quantified in-stream habitat and fish assemblages above and below all beaver dams (n = 15) and selected control sites (n = 9), adjacent to beaver dams, within an entire, low-gradient stream network (Fish Brook, MA, U.S.A.). Beaver dams altered habitat within streams in four ways based on upstream versus downstream differences in stream width, depth, velocity and substratum. In general, habitat heterogeneity, measured using two indices, was greater at beaver dams than control sites. The diversity and abundance of fish around beaver dams were positively related to habitat heterogeneity. Faster water and the coarser substratum below beaver dams increased the amount of fluvial habitat available to native fish. This alteration can be critical for fish with life histories that depend on flowing water and hard substrata. In summary, within a stream network, beaver dams maintained fish biodiversity by altering in-stream habitat and increasing habitat heterogeneity. Understanding the relationship between habitat heterogeneity and biodiversity can advance basic freshwater ecology and provide science-based support for applied aquatic conservation.
Magnesium ion chemistry in the stratosphere

Abstract Laboratory measurements of reaction rate constants of magnesium ions and magnesium containing ions with O 3 , NO, HNO 3 , and H 2 O 2 have been carried out in a flowing afterglow experiment. Mg + ions react with O 3 to produce MgO + ions, which in turn react with O 3 to produce Mg + ions. Mg + ions react with HNO 3 and H 2 O 2 to produce MgOH + ions. MgOH + ions react rapidly with HNO 3 to produce NO + 2 ions and Mg(HO) 2 . One can therefore conclude that Mg + , MgO + , or MgOH + ions could not have significant concentrations in the stratosphere if gas phase magnesium compounds were present. The failure to observe these ions therefore cannot be used as evidence that the stratospheric magnesium, resulting from meteor ablation at higher altitudes, is in condensed phases. This is in contrast to the case for sodium where the ion chemistry is such that the failure to observe hydrated Na + ions proves that gas phase sodium compounds are not present in the stratosphere.
On matters constitutional in Micronesia

(1980). On matters constitutional in Micronesia. The Journal of Pacific History: Vol. 15, No. 2, pp. 83-92.
Computer program (SEQPEP) to aid in the interpretation of high-energy collision tandem mass spectra of peptides.

An algorithm (SEQPEP) that aids in the interpretation of high-energy (greater than 1 kV) collision-induced dissociation mass spectra of peptide ions generated by fast atom bombardment (FAB) ionization is described. The only required input is a list of product ion masses and relative abundances generated by the mass spectrometer data system, the mass of the precursor [M + H]+ ion, and the mass of any C-terminal modification, if present (e.g., amide). Possible N-terminal modifications and amino acid compositions are not required as input. In the output, sequences are ranked according to the fraction of total product ion current that can be accounted for as either sequence-specific or non-sequence-specific fragment ions. These are listed by ion type. One of the major advantages of this program over algorithms described earlier is the incorporation of ion types more recently discovered. Also, this program is much faster, requiring less than 5 min of central processing unit time for an input of as many as 100 product ions. The results obtained from 50 peptides, including some generated when sequencing a protein of previously unknown structure, are discussed.
Fatigue--still the elephant in the room.

It’s O-Dark-Thirty and the call comes into the communications center. The communications specialist is actually a bit startled by the ring, as the night has been very uneventful until this moment. She has been trying desperately to stay awake with pints of coffee and snacking throughout the night as well as an occasional walk around the room and a few stretching exercises. The cobwebs are still clinging to much of the cognitive segments of the brain, but she is able to copy the scene request information down reasonably well and alert the pilot of the call awaiting a weather check. The pilot has been up much of the night and finally elected to try and get a few winks in the recliner set up in the pilot’s office. The management decided to take the beds away, figuring that they could speed up response times if the pilot was awake much of the night. The alert tones from the radio seemed like part of the restless dream he was having. He finally realized that it was a scene request tone and shook the sleepy fog from his head and took down the somewhat disjointed request. It took a few minutes to regain some awareness of the situation, and he began checking weather for the area that they had been requested to. He remembered vaguely that he had placed the communications center on “weather check” at the shift change briefing. The adrenalin was beginning to pump as he realized that the call was coming from an area that always had very critical patients or they would not have called. He put his flight planning in expeditious mode and swiftly headed for the aircraft. Four minutes or so had passed, and he arrived at the aircraft on the roof at the same moment as the clinical crew. They did a cursory walk-around, he cranked the aircraft, and they sped off into the dark night. The walkaround and start-up had been a bit rushed because the management had frequently complained of slow launch times at night. The crew complained that they had little opportunity to rest that night as the emergency room and other duties kept them on their feet since they walked in the door. They knew that the landing zones in the area would be steep and tight among the 200-foot redwoods, and it would be a moonless, misty night over the damp, forested, rolling hills a mere 10 minutes from their base. They all felt tired, but duty pushed them on.
The source of excess linewidth in EPR of triplet excitons in molecular crystals

Abstract It is shown that the EPR linewidth spectrum of triplet excitons in molecular crystals can be severely distorted by weak orientational disorder. The demonstration employs a one-parameter correction procedure based on the assumption that the angular dependence of excess width is directly proportional to the angular gradient of the resonant field. Application to the discrepant data of Haarer and Wolf brings them into agreement with theory and with more recent experiments. A phenomenological model of the disorder is used to interpret the distortion parameter. These results suggest the potential value of exciton EPR as a probe of structural imperfections in molecular crystals.
Rocky mountain spotted fever

Abstract Rocky Mountain spotted fever (RMSF) is the most frequently reported rickettsial disease in the United States. The South Atlantic states, especially North Carolina, have the highest incidence of reported cases. The causative organism is Rickettsia rickettsii, a small intracellular gram-negative bacillus. The disease is transmitted by a tick bite. The incubation period is about 1 week. Patients typically present with fever, headache, and malaise and may go on to develop a maculopapular rash that progresses to petechiae or purpura. More serious cases may result in central nervous system, hepatic, and pulmonary injury. Patients may require mechanical ventilation or hemodialysis. Long-term sequelae include neurologic deficits and limb amputations in severe cases. Empiric treatment should be started based on clinical suspicion, because serologic tests may not become positive for 7 to 10 days. Delay in diagnosis and treatment is the most important cause of morbidity and mortality. The treatment of choice is doxycycline, 100 mg bid for 1 week. Chloramphenicol may be used in patients who have a contraindication to doxycycline. There is no currently available vaccine for RMSF. With treatment, the mortality rate is still 5%. (Prim Care Update Ob/Gyns 2002;9:28–32.
Use of a vascularized fibula bone flap and intercalary allograft for diaphyseal reconstruction after resection of primary extremity bone sarcomas.

Background:The standard treatment for primary bone sarcomas of the extremities has become chemotherapy and limb salvage surgery. However, the difficulties in achieving reliable long-term healing with allograft reconstruction have led us to use vascularized fibula transfer to enhance healing.Methods:
Ion Selectine Crown-Ether Electrdes for Local Anesthetic Cations

Abstract An electrode selectively sensitive to the cationic species of aromatic amine local anesthetics is described. Poly(viny1 chloride) gel membrane containing dibenzo-24-crown-8 ether was tested for ion selectivity to the cationic forms of local anesthetics. The electrode responded ideally to dibucaine and hexylcaine among eight local anesthetics tested. A dibenzo-18-crown-6 ether electrode also responded to these two anesthetics, although less ideally. Membranes with dicyclohexyl crown ethers were not good sensors for any local anesthetics tested. The relationship between chemical structures and sensitivity is discussed.
The difficult airway: Implications for the otolaryngologist–head and neck surgeon

Clinical situations arise in which maintenance of adequate ventilation becomes technically difficult, often either in an emergency setting or perioperatively. The otolaryngologist–head and neck surgeon is frequently called upon to provide expertise in airway management. The present article discusses approaches to the patient with a difficult airway. Problems are divided into either acute or elective situations. Algorithmic approaches and specific techniques are reviewed.
Toward the sensor network macroscope

The Macroscope is a conceptual instrument for perceiving complex interactions, such as what occurs is ecosystems, social systems, and large-scale industrial settings. Sensor networks are a significant step toward such an instrument, because of the fidelity they offer in monitoring large regions of space and large collections of things. This talk describes our experiences in developing and deploying a large sensor network for microclimate monitoring of coastal redwood forests as a basis for studies in redwood ecophysiology. It summarizes the architecture, its implementation, and the many lessons and surprises encountered along the way. The effort produced unprecedented recordings of the microclimate dynamics indicating how these huge organisms interact with their environment.
The role of oxytocin in mating and pregnancy.

Abstract The hormone oxytocin (OT) is released both centrally and peripherally during and after mating. Although research in humans suggests a central role in sexuality, the most reliable findings to date involve peripheral activation. This review will discuss these results and will particularly focus on understanding the most recent findings from fMRI data and the effects of exogenous peripheral OT administration. We will then consider hypotheses of the roles played by central and systemic OT release as well as their control and modulation in the female, summarizing recent findings from animal research. Finally, we will discuss the contribution of OT to the initiation of pregnancy in rodents. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.
C3- Carbon Cluster Anion: Structure and Asymmetric Stretching Mode Frequency

Carbon cluster anions have been formed by a combination laser ablation/plasma generation method and then deposited in argon matrices and studied via Fourier transform infrared spectroscopy. In this...
Aging in the Context of Cohort Evolution and Mortality Selection

This study examines historical patterns of aging through the perspectives of cohort evolution and mortality selection, where the former emphasizes the correlation across cohorts in the age dependence of mortality rates, and the latter emphasizes cohort change in the acceleration of mortality over the life course. In the analysis of historical cohort mortality data, I find support for both perspectives. The rate of demographic aging, or the rate at which mortality accelerates past age 70, is not fixed across cohorts; rather, it is affected by the extent of mortality selection at young and late ages. This causes later cohorts to have higher rates of demographic aging than earlier cohorts. The rate of biological aging, approximating the rate of the senescence process, significantly declined between the mid- and late-nineteenth century birth cohorts and stabilized afterward. Unlike the rate of demographic aging, the rate of biological aging is not affected by mortality selection earlier in the life course but rather by cross-cohort changes in young-age mortality, which cause lower rates of biological aging in old age among later cohorts. These findings enrich theories of cohort evolution and have implications for the study of limits on the human lifespan and evolution of aging.
Effects of preadoption counseling on the prevention of separation anxiety in newly adopted shelter dogs

Separation anxiety is one of the more prevalent and difficult to treat behavior problems in dogs. The associated behaviors can be undesirable to dog owners and damage the human animal bond, leading to relinquishment or return to an animal shelter. Due to the high prevalence of separation related problems in recently adopted shelter dogs, shelter staff hold a critical role in advising and educating owners on how to prevent separation anxiety post-adoption. The aim of this study was to propose a form of that preventive counseling as a means of preventing the development of separation anxiety in recently adopted shelter dogs. The efficacy of preadoption counseling in the education and prevention of separation anxiety problems was tested in a prospective, randomized, parallel-group study. Participants included 133 new owners of dogs 6 months of age and older. At the time of adoption, sixty-six of these owners were randomly selected to receive five minutes of counseling on the prevention of separation anxiety, while the remaining sixty-seven owners served as the controls. A follow-up survey regarding the signs associated with separation anxiety and other potentially related behaviors was conducted one month post adoption. Results showed that 19 owners reported their dogs as having separation anxiety. There was no significant effect of adoption counseling on the prevention of separation anxiety. Owners in both groups were equally as likely to perform most of the recommendations given during counseling. Dogs that were reported to have separation anxiety were significantly more likely than dogs without reported separation anxiety to show nervous or panicked behavior as the owner prepared to leave (P = 0.0001) and were more likely to be reported as being “needy” (P = 0.031). Having another dog in the home was not protective against the development of separation anxiety. Owners in the counseling group were more likely than those in the control group to put food inside a toy at the time of leaving the dog home alone (P = 0.0001), suggesting the counseling recommendations were indeed followed by the owners. Owner compliance supports the idea that counseling is a useful tool for owners. Separation anxiety is a disorder whose course may be difficult to alter in recently adopted shelter dogs using only basic, interventional information. Brief counseling and a toy do not effectively prevent the occurrence of this complex behavioral condition. Further investigation should be done to find more specific, effective prevention tools for owners to use in the home to minimize the development of separation anxiety and shelter should be prepared to provide interventional resources to owners whose dogs develop separation anxiety despite these efforts.
A test of three‐dimensional radiative transfer simulation using the radiance signatures and contrasts at a high latitude coastal site

[1] A three-dimensional Monte Carlo radiation code is used to analyze surface observations of sky radiance at a high latitude coastal site. Observations were made at Palmer Station, Antarctica, under uniform marine stratus clouds during both ice-free and iced-in ocean conditions. The model results using actual snow/ocean area coverage show good qualitative agreement with all-sky images and high spectral resolution radiometer scans. When viewing over the island, toward the northeast, observations and modeling indicate that sky radiance in the visible bands is up to a factor of two greater than for directions toward the southwest, viewing out over open ocean. Owing to a decrease in snow reflectance at longer wavelengths, modeled and observed radiance distributions in the near infrared tend to be much more symmetric. Results of the modeling study indicate that details of the snow BRDF, or island topography, have a very small effect on model predictions. In addition, the model indicates that the angular distribution of sky radiance is fairly insensitive to cloud optical depth (assumed homogeneous) and is independent of cloud height as long as cloud layer thickness is not much larger than the cloud base height.
The photoplastic effect in wurtzite and sphalerite structure II VI compounds

Abstract Yielding and photoplastic effects are examined in II–VI compounds. It is shown that reversible increases in flow stress are observed in both wurtzite and sphalerite structure II–VI compounds when illuminated with light of appropriate wavelength. The observed strengthening during illumination increases with bandgap energy. Experimental results are interpreted in terms of the kinetics of dislocation motion in CdS. The activation energy for dislocation motion in light. U L = 0·50 eV and in dark, U D = 0·86 eV. These values are approximately the same as the thermal activation energy for electrical conduction in light and dark. The apparent stress dependence of the dislocation velocity is smaller in light than in dark.
On the surface temperature dependence of non-equilibrium translational energy accommodation coefficients

Abstract The formalism of classical scaling theory is applied to the process of translational energy accommodation in the gas-solid surface system. The scaling provides a systematic description of energy transfer as a function of the initial occupation numbers of the solid. This yields a relatively simple equation for the surface temperature variation of the non-equilibrium EAC, α(Tg, Ts), at fixed gas temperature. Various limits, including high temperatures and near-equilibrium, and special models of the solid surface are investigated. The quantitative accuracy of a simplified scaling formula appropriate for the case of single phonon processes is demonstrated by comparison with the results of Lennard-Jones-Devonshire-Strachan theory.
A High-Performance Controlled-Current Inverter Drive

A production variable-frequency drive is described which uses an induction motor and a controlled-current inverter. The control loops of the drive have been arranged so that the performance of the drive is extended to zero speed and to the theoretical upper limit speed. Operating modes include torque smoothing by programmed dc link current, pulsewidth modulated (PWM) current shaping, and flux-controlled constant horsepower operation.
Humanities extension seminars: The development of a program

The School of Humanities and Social Sciences at North Carolina State University has been presenting noncredit humanities seminars to diverse adult audiences throughout the state since January 1978. The purpose of the program has been to bring small groups of people with college-level intelligence together to discuss humanistic issues in a format that reflects, to some extent, the intellectual background and discipline of a university. The success of the seminars, which involve personal and videotaped presentations by university humanists, has been due primarily to the quality of the faculty involved and the resources of the Cooperative Extension Service. Though this program is best suited for land-grant universities, its basic format could be adapted in various ways to other institutional settings.
The surface chemistry of water-reducible polymer solutions/dispersions 1. Surface tension behavior

Abstract Both static tension and dynamic surface tension of water-reducible (W/R) polymer solutions were carefully examined. It is shown that the cosolvent and its concentration are controlling factors in surface tension behavior for most concentration regions of W/R polymer solutions. This is true for both static and dynamic surface tensions. The polymer and its concentration have a much smaller effect on static surface tension than does the cosolvent. Much of the dynamic surface tension correlates with the bulk shear viscosity of W/R polymer solutions. The examination of cosolvent /water mixtures shows a critical solution concentration (CSC) for most cosolvents, analogous to the critical micelle concentration (CMC) in surfactant solutions. Both CSC and CMC originate from the same structural characteristics, i.e. molecules having a hydrophilic head and hydrophobic tail. Typically cosolvents have a less hydrophobic nature so values of CSC are higher than those typical of CMC for surfactants. This CSC plays a unique role in the surface tension of W/R polymer solutions. Above the CSC, constant surface tension is observed, while below the CSC a rapid increase in surface tension with decrease of cosolvent concentration occurs.
Palliative Care Training in Surgical Oncology and Hepatobiliary Fellowships: A National Survey of the Fellows

Background Surgical oncologists (SO) and hepatobiliary (HPB) surgeons frequently care for patients with advanced diseases near the end of life, yet little is known about their training, comfort, and readiness in the provision of palliative care. This study sought to assess the quality, adequacy, and extent of palliative care training and the readiness of SO and HPB fellows in delivering palliative care.
Trade Liberalization and the Skill Premium in Developing Economies

Empirical evidence shows that while the skill premium narrowed in some developing countries following trade liberalization, it widened in others, or even exhibited non-monotonic behavior. This paper studies a simple dynamic general equilibrium trade model in which differences in initial conditions across developing countries play a key role in explaining the variety of skill premium behaviors. Differences in initial conditions in terms of skilled labor and physical capital emerge in the model due to differences in trade policies. The model can generate non-monotonic behavior for the skill premium following trade liberalization.
Radiation Fibrosis Syndrome: Neuromuscular and Musculoskeletal Complications in Cancer Survivors

Radiation-induced toxicity is a major cause of long-term disability after cancer treatment. Radiation fibrosis describes the insidious pathologic fibrotic tissue sclerosis that can occur in response to radiation exposure. Radiation fibrosis syndrome describes the myriad clinical manifestations of progressive fibrotic tissue sclerosis resulting from radiation treatment. Radiation-induced damage can include "myelo-radiculo-plexo-neuro-myopathy," causing muscle weakness and dysfunction and contributing to neuromuscular injury. Similarly, radiation damage to neuromuscular structures contributes to radiation-induced trismus and cervical dystonia in head and neck cancer survivors. This narrative review discusses the pathophysiology, anatomy, evaluation, and treatment of neuromuscular, musculoskeletal, and functional disorders that can result as late effects of radiation treatment. Rehabilitation medicine physicians with extensive training in neuromuscular and musculoskeletal medicine as well as in the principles of functional restoration are uniquely positioned to help lead efforts to improve the quality of life for cancer survivors with radiation fibrosis syndrome.
Chemical modification of fluorinated self-assembled monolayer surfaces using low-energy ion beams for halogen and pseudohalogen transfer

Isocyanatosilane-derived cations, Si(NCO) n + , (n = 1-4) were mass-selected and reacted with fluorinated self-assembled monolayer (F-SAM) surfaces at low collision energy ( < 100 eV). Examination of the scattered products revealed a variety of reactions from simple fluorine atom abstraction (e.g. formation of SiF + ) to halogen-pseudohalogen exchange products (e.g. formation of SiF(NCO) 2 + and SiF 2 (NCO) + from Si(NCO) 3 + ). Bare Si + reacts predominantly by single F-atom abstraction, but small amounts of SiF 2 + and SiF 3 + were also observed. The correlation of reactivity with thermochemistry and the role of the electronic configuration of projectile ions in multiple F-atom abstraction processes are discussed. Chemical modification of the F-SAM surface itself was shown to be a consequence of the ion-surface collisions. For example, in situ Xe + chemical sputtering analysis of F-SAM surfaces exposed to Si(NCO) n + ion beam bombardment revealed the presence of CF 2 NCO + (m/z 92). This result suggests that NCO groups are incorporated into the fluorocarbon chains at the surface, probably via a pseudohalogen-by-halogen exchange mechanism. Surface modification was also achieved using the dicyanatochloro-methyl cation, C(CN) 2 Cl + . Prolonged reactive collisions of C(CN) 2 Cl + upon a F-SAM surface led to the incorporation of both chlorine atom and cyanato groups into the surface, and these were released as CF 2 CN + (m/z 76) and CF 2 Cl + (m/z 85) on Xe + sputtering analysis. Isotopic labeling experiments confirmed Cl substitution into the surface fluorocarbon chains.
Proteins specified by Sindbis virus in chick embryo fibroblast cells

Abstract Large amounts of high molecular weight polypeptides were detected in “aged” chick embryo fibroblast cells infected with Sindbis virus. These polypeptides were shown to be virus specific by several criteria. At least some of the above polypeptides were shown to be precursors to smaller viral structural proteins by a pulse-chase experiment.
The Néel-RVB transition upon doping with static holes

Extensions of RVB wavefunctions of the form introduced by Liang, Doucot and Anderson to systems described by the t − J Hubbard model with infinitely heavy (t → 0) holes, are investigated. The self-overlaps of these wavefunctions, with long-range singlets at any amount of doping, are mapped to partition functions of statistical-mechanics systems. By identifying the classical “hamiltonians” which generate these partition functions we may infer the behavior of the RVB wavefunction as the doping is varied. Undoped states with long-range antiferromagnetic order will lose it as doping is increased. The instantaneous connected static structure factor S(q) for q = (π, π) is singular but non-diverging at the transition. The results are compared with recent work on the percolative transition of the diluted Heisenberg model in 2D.
Gender and age influence the effects of slow-wave sleep on respiration in patients with obstructive sleep apnea.

Obstructive sleep apnea (OSA) is influenced by sleep architecture with rapid eye movement (REM) sleep having the most adverse influence, especially in women. There is little data defining the influence of slow-wave sleep (SWS) on OSA. We wished to study the influence of SWS on OSA and identify differences attributable to gender and/or age, if any. Retrospective study of polysomnography (PSG) records of adult patients referred for diagnostic PSG. Records were excluded if they underwent split night or positive airway pressure titration studies, had <180 min of total sleep time (TST) and/or <40% sleep efficiency, or had SWS <5 min and/or <1% of TST. The apnea–hypopnea index (AHI) recorded during SWS was compared with that measured during other non-rapid eye movement (NREM) sleep and during REM sleep. The REM–SWS difference in AHI was measured, and compared between genders. Records from 239 patients were included. The mean AHI in all subjects was 17.7 ± 22.6. The SWS AHI was 6.8 ± 18.9, compared to the REM AHI of 24.9 ± 25.8, and NREM AHI of 15.8 ± 22.8. Females had significantly higher SWS by percentage, and lower NREM AHI (P < 0.0001) and SWS AHI (P = 0.03). Among patients with OSA (AHI ≥5), the difference between REM AHI and SWS AHI was greater in women than in men (34.2 ± 27.4 vs. 21.6 ± 26.0, P = 0.006). The upper airway appears to be less susceptible to OSA during SWS than during REM and other NREM sleep. This may be related to phase-specific influences on both dynamic upper airway control as well as loop gain. Gender and age appear to modify this effect.
Transforming an HCI Model to a Software Design Model

The software engineering and human factors communities are seeking ways to integrate their methodologies. This paper outlines an amplified, software engineering methodology that extends beyond requirements gathering to encompass human factors analyses. The methodology employs an object model that is uniform throughout the software project. It involves a procedure that seamlessly transforms a task action grammar model, from HCI theory, directly into a specification model based on user/machine dialog and, thence, into a software design model. The model's object-oriented structure makes it feasible to trace the effects of the user's needs throughout the amplified project life cycle to the final code. A case study documents evidence concerning how effectively the procedure supports the software engineering process. An examination of the extent of metamorphosis the model undergoes in the case study indicates that the transition through the amplified life history is well controlled; in particular, the transition from the software specification to the design model is more controlled than that under traditional methodologies.
A priori theory of incommensurate behavior in Rb2ZnCl4

Abstract We have performed a study of the potential energy, normal modes, static relaxation, and molecular dynamics of Rb2ZnCl4 using ab initio Gordon-Kim interionic potentials for intermolecular and interionic potentials. We find that the Pnam–Pna21 transition in this, and almost certainly many isomorphous systems, is entropy driven and shows no soft mode behavior. This is shown to arise from the presence in this system of a large equipotential volume of phase space between the Pnam and the tripled Pna21 low temperature structure. This region arises from a major lattice instability involving large rotations and displacements and having approximately six-fold screw symmetry along the a axis. This concealed imperfect symmetry which we call latent symmetry is the basic cause of the existence of a near-tripled incommensurate phase over a range of 113 K (302 K–189 K) between the Pnam and Pna21 phases. In this region the helicity is incommensurate with the lattice, being largely determined by the relief of int...
Relationship of pyridoxine and its derivatives to the mechanism of action of isoniazid.

Summary1. It was possible to inhibit growth of organisms other than Mycobacterium with isoniazid by controlling the amount of pyridoxine and its derivatives in the media. Lactobacillus plantarum and Saccharomyces carlsbergensis were inhibited in a synthetic medium by isoniazid concentrations of less than 102 M. This inhibition was competitively reversed by pyridoxine, pyridox-amine, and pyridoxal. In reversing isoniazid inhibition of Lactobacillus, pyridoxamine, and pyridoxal were from 1000 to 4000 times more effective, than pyridoxine. 2. Two strains of E. coli were inhibited with isoniazid with partial reversal with pyridoxine and derivatives. Larger amounts of the metabolite were required and the reversal was not as typically competitive. 3. No reversal of isoniazid inhibition could be obtained with vit. B6 or its derivatives in any of the Mycobacteria tested. If isoniazid acts as an antagonist of pyridoxine or its derivatives in the Mycobacteria, it is not a simple substrate competition or uptake phen...
EPIDURAL ANALGESIA DURING LABOUR IN TWIN PREGNANCY

We report on the use of epidural analgesia during labour in 58 out of a total of 234 twin deliveries performed over a five-year period. A comparable control group consisted of 44 twin pregnancies delivered consecutively during the year preceding the introduction of epidural analgesia into our department. Epidural analgesia shortened the mean time of labour and made possible the performance of all necessary instrumental and obstetrical manoeuvres, without additional anaesthesia or adverse effects on the second twin. The epidural group required oxytocin more often due to an increased incidence of hypotonic uterine dysfunction. There was also a considerable increase of instrumental deliveries in the epidural group. The condition of the newborn infants of both groups, evaluated by Apgar score at one minute, was similar, but there was a higher perinatal mortality among pre-term infants delivered under epidural analgesia. Epidural analgesia was found to be an acceptable method of relieving pain in twin labour, but because of the increased necessity to use oxytocin and the relatively high perinatal mortality observed among pre-term infants, further experience is necessary before it can be claimed that this is the method of choice for relief of pain in twin labour.
Generation of high curvature membranes mediated by direct endophilin bilayer interactions

Endophilin 1 is a presynaptically enriched protein which binds the GTPase dynamin and the polyphosphoinositide phosphatase synptojanin. Perturbation of endophilin function in cell-free systems and in a living synapse has implicated endophilin in endocytic vesicle budding (Ringstad, N., H. Gad, P. Low, G. Di Paolo, L. Brodin, O. Shupliakov, and P. De Camilli. 1999. Neuron. 24:143-154; Schmidt, A., M. Wolde, C. Thiele, W. Fest, H. Kratzin, A.V. Podtelejnikov, W. Witke, W.B. Huttner, and H.D. Soling. 1999. Nature. 401:133-141; Gad, H., N. Ringstad, P. Low, O. Kjaerulff, J. Gustafsson, M. Wenk, G. Di Paolo, Y. Nemoto, J. Crun, M.H. Ellisman, et al. 2000. Neuron. 27:301-312). Here, we show that purified endophilin can directly bind and evaginate lipid bilayers into narrow tubules similar in diameter to the neck of a clathrin-coated bud, providing new insight into the mechanisms through which endophilin may participate in membrane deformation and vesicle budding. This property of endophilin is independent of its putative lysophosphatydic acid acyl transferase activity, is mediated by its NH2-terminal region, and requires an amino acid stretch homologous to a corresponding region in amphiphysin, a protein previously shown to have similar effects on lipid bilayers (Takei, K., V.I. Slepnev, V. Haucke, and P. De Camilli. 1999. Nat. Cell Biol. 1:33-39). Endophilin cooligomerizes with dynamin rings on lipid tubules and inhibits dynamin's GTP-dependent vesiculating activity. Endophilin B, a protein with homology to endophilin 1, partially localizes to the Golgi complex and also deforms lipid bilayers into tubules, underscoring a potential role of endophilin family members in diverse tubulovesicular membrane-trafficking events in the cell.
Efficient algorithm for multispectral data coding using approximate trigonometric expansions

Abstract Images obtained from satellite and airborne multispectral collection platforms exhibit a high degree ofspatial and spectral correlations that must be properly exploited in any multispectral bandwidth corn-pression scheme. Removing the inherent spectral correlation in the data results in a significant corn-paction of data to be coded. Discrete approximate trigonometric expansions have previously beenproposed for exploiting spatial correlation in one-dimensional signals and images for the purpose ofcoding. In this paper, we apply the approximate trigonometric expansions to multispectral data, and explore their capability of spectral decorrelation across bands. We show that the compression algorithms employing approximate trigonometric expansions to multispectral imagery provide fast implementationand some how better spectral decorrelation efficiency than discrete cosine transform (DCT). Forcomparison purposes, the results are compared with the techniques employing the discrete cosinetransform (DCT). Computer simulation results are presented.Key words: Adaptive transform coding, Multispectral data coding, Approximate Fourier expansion,Approximate cosine Expansion, Multispectral data compression.
Nuclear resonance and susceptibility study of Pt-Rh alloys

Low-temperature [$T\ensuremath{\approx}(1\ensuremath{-}4)$\ifmmode^\circ\else\textdegree\fi{}K] measurements of the Knight shift and spin-lattice relaxation time for $^{103}\mathrm{Rh}$ and $^{195}\mathrm{Pt}$ in ${\mathrm{Pt}}_{1\ensuremath{-}x}{\mathrm{Rh}}_{x}$ for $0\ensuremath{\le}x\ensuremath{\le}1.0$ have been carried out using transient NMR methods. Bulk magnetic susceptibilities of these alloys as a function of temperature were also measured. The magnitude of the $^{103}\mathrm{Rh}$ Knight shift and relaxation rate increased monotonically with decreasing $x$ to the point that exchange enhancement effects dominate the NMR at $x=0.03$. In this low Rh content or impurity region the local susceptibility at the Rh site was approximately five times the Pt susceptibility. The localization is gradually increased with concentration as evidenced by the smooth monotonic increase in the ratio of $^{103}\mathrm{Rh}$ to $^{195}\mathrm{Pt}$ Knight shift as $x$ decreased. The magnitude of the $^{195}\mathrm{Pt}$ resonance shift was found to track the bulk susceptibility with both quantities exhibiting maxima near $x\ensuremath{\approx}0.2$. Here, in contrast to the Rh NMR, rigid-band considerations are qualitatively applicable in that the maxima reflect the peak in density of states of Pt known to occur just below the Fermi energy. Extended polarization of the Pt sublattice around Rh impurities probably accounts for the rigid-band nature of the Pt NMR. The experimental nuclear-nuclear exchange constants for $^{195}\mathrm{Pt}$ were approximately 4.5 kHz and very weakly concentration dependent.
New light on weibull theory

Abstract In 1939 Weibull applied weakest link theory to the interpretation of the variability of fracture stress of nominally indentical specimens. He attributed this variation to the presence of sources of weakness, or flaws, that were given a strength, but no other physical properties. Accordingly, his theory rests primarily on the statistics of extreme values. It is now generally believed that the most important sources of weakness are microcracks. Thus, an ideal statistical theory of fracture must take into account fracture mechanics and material microstructure. The present paper outlines recent progress along these lines and shows how the resulting more fundamental theories reduce to Weibull theory when certain simplifying assumptions are made.
Floral fragrance variation in Cypripedium: Implications for evolutionary and ecological studies

The floral fragrance compositions of eight species (including two putative varieties) of Cypripedium were determined by GC-mass spectrometry. Substantial diversity in fragrance compound skeletal type was detected and included benzenoid, terpenoid and fatty alcohol derivatives. Qualitative fragrance variation was investigated within and between two populations of Cypripedium calceolus var. parviflorum. The clustering algorithm, unweighted pair group method arithmetic average (UPGMA) was used as an objective analytical means to assess population-level fragrance variation relative to species-level variation. Members from two populations of C. calceolus var. parviflorum formed a single cluster with similarity values ranging from 0.36 to 1.0, indicating a high degree of biogenetic uniformity among some individuals as well as substantial relative divergence between others. The results of this study indicate that conclusions about taxonomic or pollinator relationships, based upon limited infraspecific sampling of floral fragrance, should be considered tentative until the extent of population variation is investigated.
A Simplified Method for the Resolution of the Orthogonal Electrocardiogram

The question as to whether unipolar precordial electrocardiographic leads provide clinical information not contained in a 3-lead orthogonal electrocardiogram remains unanswered. A simple, inexpensive switching-type resolver was designed for the investigation of this problem.
Peripubic urethropexy for urinary stress incontinence in women.

Abstract A technique for urinary stress incontinence is described that suspends the bladder neck and urethra by placing two vertical sutures along each posterior-lateral side of the entire urethra and tying them completely around the pubic bones. Six cases are reported and results given.
Linear programming with estimatable parameters

Problems of estimating parameters in a linear programming model and using it in production planning are discussed here. An empirical application illustrates the various aspects of the estimation problem.
Group 11 Metal Complexes of N-Heterocyclic Carbene Ligands: Nature of the Metal-Carbene Bond

The silver complex of the tripodal N-heterocyclic carbene ligand TIMEMe, [(TIMEMe)2Ag3](PF6)3 (3), reacts with copper(I) bromide and (dimethyl sulfide)gold(I) chloride to yield the corresponding D3-symmetrical copper(I) and gold(I) complexes [(TIMEMe)2Cu3](PF6)3 (4) and [(TIMEMe)2Au3](PF6)3 (5). Single-crystal X-ray diffraction, spectroscopic, and computational studies of this series of metal NHC complexes are described. The group 11 metal complexes of the TIMEMe ligand exhibit isostructural geometries, with three metal ions bridging two of the TIMEMe ligands. Each metal ion is linearly coordinated to two carbene centers, with each of the carbenoid carbons stemming from a different ligand. Overall, the molecules possess D3 symmetry. The electronic structure of these newly synthesized compounds was elucidated with the aid of DFT calculations. In contrast to the common assumption that NHCs are pure σ-donor ligands, our calculations reveal the existence of both σ- and π-type interactions between the metal io...
Direct-current injury from external pacemaker results in tissue electrolysis.

Abstract In two patients undergoing open heart operations, electrochemical bums developed at the sites of connection to an external pacing system. Investigation revealed that failure of the pacing generator caused a small, continuous, direct current to pass through the patients, resulting in electrolysis at the sites of contact with the pacing and grounding wires. This electrolytic reaction was recreated in a mock pacing system and resulted in tissue injury and disintegration of the pacing wire. Guidelines to help recognize and prevent this complication are presented.
Phenolic constituents of glandular trichomes onSolanum berthaultii andS. polyadenium

Phenolic compounds in Type A glandular trichomes of two insectresistant potato species were separated and identified using a combination of high pressure liquid chromatography (HPLC), UV-visible spectrometry, and1H proton nuclear magnetic resonance (NMR) procedures. Type A trichomes ofSolanum berthaultii andS. polyadenium contained a phenolic compound tentatively identified as the glucose ester of p-hydroxyphenylpropionic acid. Its presence in trichomes of both species suggests that this compound may play a major role in formation of the brownish, insect entrapping exudate characteristic of trichome-mediated insect resistance in these species. Chlorogenic acid, a major phenolic constituent of Type A trichomes ofSolanum polyadenium was not detected in trichomes of 5.berthaultii. The exclusive presence of chlorogenic acid in trichome exudates ofS. polyadenium may be responsible, at least in part, for the greater levels of insect entrapment by this species, compared with that ofS. berthaultii.
A model for the effect of line width and mechanical strength on electromigration failure of interconnects with “near-bamboo” grain structures

A simple analytical model for the effect of mechanical strength and line width (for the case of narrow lines) on the electromigration failure of metallic interconnects is presented. Because the line width/grain size ratio and the diffusivity enter differently in the model, application of the resulting failure time equation to published data can provide insight into the mechanisms of enhancement of electromigration resistance by grain structure optimization and alloying.