cssi/SciSciGPT-SciSciNet huggingface dataset:
Anesthesia for cardioversion

Elective electrical cardioversions are commonly scheduled to be performed in the PACU because of the availability of nursing and anesthesia support. This report examines preanesthetic patient preparation as well as a review of the procedural aspects of electrical cardioversion. The commonly used anesthetic agents are contrasted with regard to their pharmacodynamic considerations. The indications, contraindications, and complications associated with the procedure are reviewed.
A Spectrophotometric Technique for Detecting Companions of Low-Mass M Dwarfs

The most common stars in the Galaxy are the main-sequence M dwarfs, yet current techniques are not optimized for detecting companions around the lowest mass M dwarfs, those with spectral designations ranging from M6 to M10. Described in this paper is a search for companions around such stars using a newly designed differential spectrophotometric technique. This novel method combines the strengths of the photometric and spectroscopic techniques, while it minimizes their inherent limitations. The scientific goal of this project is to search for short-period systems containing brown dwarfs and giant planets. The detection of or placing limits on such systems will help discriminate among competing theories of planetary formation.
Annealing Effect on the Shape Memory Properties of Amorphous NiTi Thin Films

Thin film shape memory alloys have recently become a promising material for the actuation of devices on the microscale such as micropumps and microvalves. Their utilization, however, has been limited due to the difficulty in tailoring their properties for different applications. Control over the transformation temperatures as well as mechanical and shape memory properties is required to enable their widespread use. This study examines the effects of heat treatment time and temperature on the properties of amorphous, Ti-rich NiTi thin films on silicon substrates. The effects on the transformation temperatures are investigated through the use of temperature dependent optical microscopy and temperature dependent X-ray diffraction. The indentation modulus and hardness, as well as dissipated energy and depth recovery, are obtained through nanoindentation and atomic force microscopy. The role of microstructure and composition in altering both the mechanical and shape memory properties of the films is discussed.
Realizing the performance potential of Cobol

It is shown how to reduce computer usage significantly by building performance into the code. Compiler performance is first defined, and three Cobol environments chosen to illustrate compiler performance in various settings are described: two mainframes and one personal computer. The usage clause, data fields, data-type conversions, tables, file-blocking efficiencies, 'perform' and 'call' overhead, sorting efficiency, ISAM file performance, and compiler options are discussed. Ten steps to improve program performance in an organization's installation are recommended. >
Pb K-shell ionization probability in high-energy Xe+Pb collisions

Probabilities for PbK-shell ionization in 5.9-, 7.2-, and 8.5-MeV/a.m.u. Xe+Pb collisions for impact parameters between 10 and 60 fm are reported. The measured probabilities are compared with theories of 1sσ-vacancy production.
Rotating coordinates as tools for calculating circular geodesics and gyroscopic precession

If an axially symmetric stationary metric is given in standard form (i.e. in coordinates adapted to the symmetries) the transformationφ→φ′ =φ-ωt (ω=constant) of the azimuthal angle leads to another such standard form. The spatial latticeL′ corresponding to the latter rotates at angular velocityω relative to the latticeL of the former. For the standard form of a stationary metric there are simple formulae giving the four-acceleration of a given lattice point and the rotation of a gyroscope at a given lattice point. Applying these formulae toL′, we find the condition for circular paths about the axis inL to be 4-geodesic, and also the precession of gyroscopes along circular paths which are not necessarily geodesic. Among other examples we re-obtain the complete geodesic structure of the Godel universe, and the gyroscopic precessions associated with the names of Thomas, Fokker and de Sitter, and Schiff.
Quantitative Short-term Study of Anal Sphincter Function After Chemoradiation for Rectal Cancer

Hypothesis Pelvic irradiation adversely affects anal sphincter function after proctectomy with coloanal anastomosis for low rectal and middle rectal ( Design Case-control study. Setting Private, tertiary care referral center. Patients Patients treated for low rectal adenocarcinoma between January 1, 1994, and October 31, 1999. Interventions Anal manometric data were prospectively collected at the time of initial diagnosis and before ileostomy closure. Main Outcome Measures Mean and maximum resting pressures (RPs) and squeeze pressures, threshold volume for sensation, and maximal tolerable volume. Results Twenty-three patients in the surgery group and 19 in the chemoradiotherapy group were considered for analysis; 15 patients had preoperative radiotherapy and 4 had postoperative radiotherapy. At the time of ileostomy closure, RPs were significantly lower in the chemoradiotherapy group than in the surgery group (32.7 ± 17 vs 45.3 ± 18 mm Hg; P = .03). Squeeze pressures were not significantly different between the surgery and chemoradiotherapy groups (108.7 ± 56.7 vs 102.0 ± 52.6 mm Hg; P = .69). The ratios of postresection to preresection RPs were also significantly lower in the chemoradiotherapy group (0.49 ± 0.29) than in the surgery group (0.76 ± 0.22) ( P = .005). Eight to 12 weeks after proctectomy with coloanal anastomosis, a 24% decrease in RP was noted in the surgery group. The addition of adjuvant pelvic irradiation decreased RP by another 27%. Conclusion Adequate shielding of the anal sphincter should be performed for low rectal cancers whenever a sphincter-preserving procedure is considered.
Carbide precipitation in austenitic stainless steel carburized at low temperature

Abstract Low-temperature gas-phase carburization can significantly improve the surface mechanical properties and corrosion resistance of austenitic stainless steel by generating a single-phase “case” with concentrations of interstitially dissolved carbon exceeding the equilibrium solubility limit by orders of magnitude. Upon prolonged treatment, however, carbides (mostly χ, M5C2) can precipitate and degrade the properties. High-resolution and spatially resolved analytical transmission electron microscopy revealed the precise carbide–austenite orientation relationship, a highly coherent interface, and that precipitation only occurs when (i) the carbon-induced lattice expansion of the austenite has reached a level that substantially reduces volume-misfit stress and (ii) diffusional transport of nickel, chromium, and iron – enhanced by structural defects – can locally reduce the nickel concentration to the solubility limit of nickel in χ-carbide.
Factors influencing the synthesis of tunable clay–polymer nanocomposites using bentonite and polyacrylamide

Abstract Although clay–polymer nanocomposites have been successfully produced in the material science field, they are typically utilized as static structures. That is, no further structural modification is expected due to the irreversible interaction of the polymer and clay particles. Yet, polymer-intercalated clay nanocomposites may be produced with environmentally-responsive polymers such that the final nanocomposites are “tunable”. The conformation of responsive polymers varies with external environmental conditions such as pH, ionic concentration, temperature, and electric field. The purpose of this study is to develop an optimized procedure for synthesizing tunable clay–polymer nanocomposites using an expansive clay mineral (bentonite) and a responsive polymer for the future production of “tunable” clay soils. The nanocomposites were produced using a solution intercalation technique. Variables investigated include synthesizing temperature, clay content, polymer molecular weight, pH, and clay-to-polymer volume ratio. Changes in the basal spacing of montmorillonite were characterized using X-ray diffraction. Intercalation was not found to vary with mixing and drying temperature. The polymer solution pH variation did not cause significant mineral dissolution, evidenced by nuclear magnetic resonance as well as X-ray diffraction. Optimum conditions for the greatest quantity of intercalated structure were at clay content of 0.001, synthesis with a low molecular weight polymer, and clay-to-polymer volume ratio of 2. Measured total specific surface area implies that the interlayer distances of synthesized nanocomposites vary with pH.
A New Model for Sexual Assault Protection Creation and Initial Testing of Elemental

Sexual assault self-protection programs often address either broad educational goals (e.g., alcohol awareness, gender, and safety) or are restricted to the practice of violent hands-on self-protect...
Critical temperatures and pressures of substances from vapor pressure data

A method has been developed for the prediction of the critical temperature and pressure of any pure substance from its reliable vapor pressure data. These data are used to determine the constants A, B, C, and D of the substance for the Frost-Kalwarf equation. The critical temperature of the substance is then calculated from the constants B and C. The critical pressure is calculated by substituting the values of A, B, C, and the calculated critical temperature into the Frost-Kalwarf equation applied at the critical point. This approach was used to calculate critical constants for 64 non-hydrogen bonding substances of all types which were primarily hydrocarbons. An average deviation of 0.59% resulted for the critical temperature and 3.18% for the critical pressure. Une methode pour la prediction des temperature et pression critiques de toute substance pure a l'aide de donnees de tension de vapeur a ete developpee. Ces donnees sont utilisees pour determiner les constantes A B C et D de la relation de Frost-Kalkwarf. La temperature critique de la substance est alors calculee depuis les constantes B et C. La pression critique est calculee en substituant les valeurs A B et C et la temperature critique dans la měme relation applicable au point critique. Cette methode a ete utilisee pour calculer les constantes critiques de 64 substances consistant principalement d'hydrocarbures. Une deviation moyenne de 0.59% pour la temperature critique et de 3.18% pour la pression critique a ete enregistree.
Nuevas tendencias y conceptos en el diagnóstico y tratamiento de la acalasia

Resumen En las 2 ultimas decadas, hemos sido testigos de una revolucion en el tratamiento de la acalasia esofagica. Actualmente, la miotomia laparoscopica de Heller con funduplicatura parcial se considera, en la mayoria de los centros, el tratamiento primario, mientras que el tratamiento endoscopico, es decir la dilatacion neumatica, se reserva principalmente para el tratamiento de pacientes que no son aptos para la cirugia o para cuando esta fracasa. Recientemente, se ha propuesto un nuevo enfoque para la acalasia: la miotomia endoscopica peroral (POEM), que combina las ventajas de la endoscopia con las de la cirugia. Este articulo revisa la evolucion del diagnostico y del tratamiento de la acalasia esofagica en los ultimos 20 anos.
Method for interactive manipulation and animation of volumetric data (Proceedings Only)

ABSTRACT We outline an efficient method for visualizing and manipulating volumetric data, in particular, cardiac MRIdata sets. The approach is designed to allow interactive manipulation and real-time animation of volumetricdata sets. The underlying model provides an efficient graphical representation for interactive rendering whilenot eliminating data from the volume of interest. We believe this model to be a valuable medical imagingtool that is applicable to other volume rendering problems. 1. INTRODUCTION The advent of medical scanning technologies such as Computer Tomography (CT) and Magnetic Resonance Imaging (MRI) provides clinicians with volumetric image data capturing physiologic and anatomic information. Currently, these images are either transferred to film or displayed on a monitor for viewing by a physician. When the tissue of interest encompasses a volume the number of tomographic images produced makes a concise integrated display difficult. Computer graphics and medical imaging researchers
Functional polymers and sequential copolymers by phase transfer catalysis. XIX. Thermotropic polythioethers and copolythioethers based on 4,4′-dithiolbiphenyl†

Thermotropic liquid crystalline (LC) polythioethers and copolythioethers have been synthesized from 4,4′-dithiolbiphenyl (TB) and α,ω-dibromoalkanes having between two and twelve methylene units. Copolythioethers were prepared from TB and a 1:1 mol/mol ratio of 1,5-dibromopentane and α,ω-dibromoalkanes having nine to twelve methylene units. Peculiarities of the phase-transfer catalyzed (PTC) polyetherification reaction in the preparation of these polymers have led to aliphatic-ether structural units. This side reaction has been explained by a possible neighboring group effect with sulfur, through sulfonium formation, and is consistent with a mechanism previously proposed in PTC polyetherifications. While not significantly enhancing solubility, the copolymeric nature of these polymers have led to lower melting and isotropization temperatures with broad mesophase thermal stability ranges. Lastly, unique spherulitic textures resembling higher-ordered smectic mesophases have been observed in all the prepared polymers.
Beam-Plasma Instabilities in a 2D Yukawa Lattice

We consider a 2D Yukawa lattice of grains, with a beam of other charged grains moving in the lattice plane. In contrast to Vlasov plasmas, where the electrostatic instability excited by the beam is only longitudinal, here both longitudinal and transverse instabilities of the lattice phonons can develop. We determine and compare the transverse and longitudinal growth rates. The growth rate spectrum in wave number space exhibits remarkable gaps where no instability can develop. Depending on the system parameters, the transverse instability can be selectively excited.
Impaired glycemia increases disease progression in mild cognitive impairment

Insulin resistance and type 2 diabetes are associated with cognitive decline and increased risk for Alzheimer's disease (AD). Relatively few studies have assessed the impact of metabolic dysfunction on conversion to AD in mild cognitive impairment (MCI), and it is unclear whether glycemic status is associated with clinically relevant measures of cognitive decline and brain structure in MCI. This study used the Alzheimer's Disease Neuroimaging Initiative database to examine the relationship of baseline glycemia with conversion to AD and longitudinal clinical, cognitive, and imaging measures of decline. Subjects with MCI (n = 264) with baseline and 2-year Clinical Dementia Rating data available were classified according to American Diabetes Association criteria for fasting glucose at baseline. The groups were normoglycemic (fasting glucose, <100 mg/dL; n = 167) or impaired glycemia (fasting glucose, ≥ 100 mg/dL, n = 97). The impaired glycemia group included individuals with fasting glucose that either reached the American Diabetes Association cut point for impaired fasting glucose or individuals with diagnosed diabetes. Two-year change in Clinical Dementia Rating-Sum of Boxes, cognitive performance testing (global cognition), brain volume (whole-brain and hippocampal volume), fluorodeoxyglucose-positron emission tomography, and conversion to AD were assessed. Subjects with normoglycemia at baseline had less functional (Clinical Dementia Rating-Sum of Boxes) and global cognitive decline over 2 years than subjects with impaired glycemia. Subjects with normoglycemia also lost less whole-brain volume and exhibited lower conversion from MCI to AD. There was no difference in hippocampal volume change or fluorodeoxyglucose-positron emission tomography between groups. These results suggest that baseline glycemia is related to cognitive decline and progression to AD.
The metabolic activation of 2-aminofluorine, 4-aminobiphenyl, and benzidine by cytochrome P-450-107S1 of Pseudomonas aeruginosa.

Abstract Pseudomonas aeruginosa is an important opportunistic pathogen of the human urinary bladder. Similar to rat liver S9, the cell-free extract from P. aeruginosa caused significant increase of histidine reversion numbers with the Salmonella typhimurium tester strain TA98 in the Ames Salmonella mutagenicity assay in the presence of either 2-aminofluorene, 4-aminobiphenyl, or benzidine procarcinogens. The presence of cytochrome P-450 protein in the cell-free extract was demonstrated by the carbon monoxide difference spectrum. We employed gene knockout technology to inactivate one of the three known putative cytochrome P-450 genes of P. aeruginosa , namely CYP107S1, which we postulated to be the most likely to induce activation. The ampicillin resistant gene from PUC19 DNA confers carbenicillin resistance to P. aeruginosa . We inserted a synthetic ampicillin gene flanked by 40 base-pairs of the 5′ and 3′ untranslated region of the CYP gene by electroporating the synthetic gene into electrocompetent P. aeruginosa cells. CYP107S1 knockout strains were selected on 1000 μg/ml carbenicillin plates. A single cloned carbenicillin resistant colony was isolated and used to determine its mutagenic capacity using Ames Salmonella mutagenicity assay. The results showed that Salmonella TA98 tester strain returned the number of revertants to its baselines level indicating the lack of metabolic activation of procarcinogens in the P. aeruginosa CYP107S1 knockout cell-free extract. In addition, the characteristic cytochrome P-450 peak determined by the carbon monoxide difference spectrum was completely absent in the cell-free extract from this CYP107S1 knockout strain bacterium. Homologous recombination of the synthetic ampicillin gene on the CYP 107S1 P-450 locus was confirmed by PCR on purified genomic DNA extracted from the knockout bacterium. The metabolic activation of tested procarcinogens is, therefore, carried out by CYP107S1 in P. aeruginosa .
LACK OF BETA-ADRENERGIC ACTIVITY OF ISOFLURANE IN THE DOG: A COMPARISON OF CIRCULATORY EFFECTS OF HALOTHANE AND ISOFLURANE AFTER PROPRANOLOL ADMINISTRATION

The studies were undertaken to determine whether isoflurane inhalation is associated with a degree of beta-adrenergic action that is potentially important in clinical situations, and to compare the circulatory tolerance to isoflurane and halothane in dogs following beta blockade. We measured arterial and pulmonary artery pressure, left and right ventricular filling pressure, heart rate and cardiac output, and derived stroke volume and systemic and pulmonary vascular resistances in 13 mongrel dogs. The haemodynamic response to 1 MAC and 2 MAC isoflurane was studied in seven dogs and was similar before and after propranolol 0.1 mg/kg i.v. In six dogs, propranolol 0.5 mg/kg caused no significant changes in the circulatory response to 1 MAC and 2 MAC isoflurane or 1 MAC halothane. However, in three dogs, administration of 2 MAC halothane after propranolol 0.5 mg/kg resulted in such profound circulatory depression as to preclude further study. These data suggest that (a) isoflurane possesses no clinically important beta-adrenergic stimulating activity; (b) there is no adverse drug interaction upon the circulation with the combination of isoflurane and propranolol; (c) in the presence of moderate to profound beta-adrenergic blockade, 2 MAC isoflurane may be tolerated better than 2 MAC halothane
Economic issues with follow-on protein products.

The potential for cost savings from the introduction of 'follow-on' versions of protein therapeutics is a major focus of the ongoing debate around the creation of a regulatory pathway for the abbreviated approval of such products. Lanthier and colleagues explore the economic issues relevant to this debate by assessing total sales, product complexity and patent expiry for current protein products. The economic effects of the possible introduction of 'follow-on' protein products have been the subject of recent debate. Here, we aim to explore the economic issues surrounding this debate using three measures: total sales, product complexity and patent expiry. Our analysis shows that the sales of therapeutic protein products are concentrated in a relatively small number of branded products, which may be the most attractive targets for follow-on development. For the years 2013–2015, we estimate that products representing US$20 billion in annual sales — approximately half of all sales in 2006 — can be expected to lose patent protection.
A randomized paired comparison trial of cutaneous treatments for acute jellyfish (Carybdea alata) stings.

Abstract The objective of the study was to compare cutaneous treatments (heat, papain and vinegar) for acute jellyfish ( Carybdea alata ) stings. Healthy adult volunteer subjects received a single-tentacle jellyfish sting on each forearm. One forearm was treated with hot-water immersion (40-41°C). This was compared with the other forearm, which was randomized to a comparison treatment of papain meat tenderizer or vinegar. Pain was measured at 0, 2, 4, 6, 8, 10, 15, and 20 minutes using a 10-cm visual analog scale (VAS). For 25 subject runs, the average VAS scores at t=0 were 3.6 cm (hot water) and 3.7 cm (comparison treatment). At t=4 minutes (2 minutes after treatment had started), the differences between hot-water and comparison group VAS scores were 2.1 cm versus 3.2 cm, respectively. The mean difference between hot-water and comparison treatments was 1.1 cm (95% confidence interval, 0.6 to 1.6). At t=20 minutes (the end of the study period), the differences between hot-water and comparison group VAS scores were 0.2 cm versus 1.8 cm, respectively. The mean difference between hot-water and comparison treatments was 1.6 cm (95% confidence interval, 0.9 to 2.3). This study suggests that the most efficacious initial treatment for C alata jellyfish envenomation is hot-water immersion to the afflicted site. (Am J Emerg Med 2002;20:624-626. Copyright 2002, Elsevier Science (USA). All rights reserved.)
Mössbauer spectroscopy as a tool in the search for evidence of past life on Mars

Iron Mossbauer spectroscopy has provided evidence for the presence in deep-sea smoker vents of superparamagnetic material, which is correlated with anaerobic bacteria found to thrive there. The finding of superparamagnetic terrestrial vent material suggests that prospecting for such material on Mars may be a way to locate sites with micropaleontological potential.
Prospective study of supplemental vitamin K therapy in patients on oral anticoagulants with unstable international normalized ratios.

It is not known whether patients on oral vitamin K antagonists who have unstable INRs achieve more stable INRs with daily vitamin K supplementation. We sought to determine whether vitamin K supplementation may decrease INR variability in patients with a history of unstable INRs, how soon the INR decreases after vitamin K therapy is initiated, the time to reach a therapeutic INR after vitamin K initiation, and how much of an increase in oral anticoagulant dose is needed to maintain the INR in the desired range. This is a prospective open label crossover study of patients on warfarin with a history of fluctuating INRs. A 9 week observation phase was followed by an 8 week period with patients receiving 500 μg of oral vitamin K daily. INRs were determined once weekly with a home point of care monitoring instrument. Vitamin K supplementation led to a decrease in INR variability in five of the nine patients studied (56%). INR decrease occurred 2–7 days after initiation of vitamin K. Therapeutic INRs were achieved 2–35 days after vitamin K therapy was initiated and an increase in warfarin dose of 6–95% was required to bring the INR back into the therapeutic range. INR fluctuations may decrease in selected patients with unstable INRs who receive vitamin K supplementation. A study with a larger sample size and longer follow-up period is needed. The results of the present study can help design such a study.
Obstetric implications of neanderthal robusticity and bone density

Neanderthal pelvic morphology is not well understood, despite the recent find and analysis of the Kebara 2 pelvis. Many of the proposed hypotheses focus on the possible need for a larger birth canal. A previously unexplored aspect involves possible direct obstetric implications of bone robusticity and density. These characteristics ocan affect obstetrics in modern humans, especially the molding of the neonate's head during parturition: engineering studies have shown that denser neonate cranial bones undergo less deformation, and thicker (more robust) cranial bones would also be expected to deform less during the birth process. These bone characteristics may also result in a less flexible birth canal. Thus, more robust or denser bones could result in the need for a larger birth canal or a smaller neonate head, due to decreased flexibility. Examples from modern populations are discussed and the conclusions applied to Neanderthals, who are known to have had high bone robusticity and may have had high bone density, given their heavy musculature. (A positive association between muscle mass and bone density has been observed repeatedly in modern humans.) We conclude that bone robusticity and density may have obstetrical implications for Neanderthals, with particular importance for neonate head molding during birth.
Malignant islet-cell tumors of the pancreas.

Although malignant islet-cell tumors are uncommon, they are an important group of pancreatic neoplasms because appropriate treatment can often result in effective palliation even though cure is infrequent. In general, these tumors are relatively slow growing so that a combination of surgical and chemotherapeutic measures may prove very beneficial. In some patients with tumors hypersecreting insulin, gastrin, glucagon, or vasoactive intestinal polypeptide (VIP), the hormonal effects of the neoplasm can be life-threatening. Surgical treatment must, therefore, consider both the functional and malignant characteristics of the individual tumor. In many patients with functional tumors, surgical debulking of the primary tumor may be indicated even when a curative resection cannot be accomplished. Some malignancies may be cured by an appropriate pancreatic resection even when peripancreatic lymph nodes are already involved. Although a Whipple procedure is not indicated when hepatic metastases are present, this procedure may cure tumors localized to the pancreatic head and/or peripancreatic lymph nodes. Because hepatic metastases are usually multiple and involve both lobes, liver resections, other than wedge excisions of peripherally located functional metastases, are not indicated. Malignant nonfunctioning islet-cell tumors are probably best treated with systemic or regional chemotherapy when metastatic. Surgical resections or bypass procedures may be infrequently useful in those cases in which the primary tumor causes either duodenal or bile duct obstruction. The most effective methods used to control hepatic metastases are systemic and hepatic arterial chemotherapy. An alternative is selective hepatic artery embolization. Recently, an implantable hepatic arterial infusion pump has been used with encouraging results in this group of patients. The chemotherapeutic agents that have been most effective in the treatment of hepatic metastases include streptozotocin, DTIC, and fluorouracil.
VEPSD: a novel velocity estimation algorithm for next-generation wireless systems

A novel algorithm called velocity estimation using the power spectral density (VEPSD), which uses the Doppler spread in the received signal envelope to estimate the velocity of a mobile user (MU), is introduced in this paper. The Doppler spread is estimated using the slope of the power spectral density (PSD) of the received signal envelope. The performance of the VEPSD algorithm is evaluated in both Rayleigh and Rician fading environments. The sensitivity of the estimation error to additive white Gaussian noise (AWGN), Rice factor (K), and the angle of arrival of the line-of-sight (LOS) component is analyzed and compared with the level crossing rate (LCR) and covariance-based velocity estimators. Simulation results show that VEPSD estimates the velocity of MUs accurately. It is also shown that VEPSD can be used for velocity estimation under nonisotropic scattering and is well suited for next-generation wireless systems (NGWSs).
Remaining skeptical: Bridling for and with one another

In this article, we argue that being our own best critics is a process by which we commit to interrogating what we know (or think we know) as we design a study. We situate the idea of bridling within the philosophical and methodological conversation of a more traditional notion in phenomenological research, bracketing, and then within Macbeth’s three expressions of reflexivity in qualitative research. Based on our analysis of some of our methodological decisions, we articulate four pivotal issues we faced. We close by making specific suggestions for faculty and graduate students individually and as research teams to consider as they strive to be their own best critics in their research.
Cloning, sequencing, and mutational analysis of the hyb operon encoding Escherichia coli hydrogenase 2.

Abstract The genes encoding the two structural subunits of Escherichia coli hydrogenase 2 (HYD2) have been cloned and sequenced. They occur in an operon (hyb) which contains seven open reading frames. An hyb deletion mutant (strain AP3) failed to grown on dihydrogen-fumarate medium and also produced very low levels of HYD1. All seven open reading frames are required for restoration of wild-type levels of active HYD2 in AP3. The hyb operon was mapped at 65 min on the E. coli chromosome.
Adverse reproductive outcomes in urban women with adeno-associated virus-2 infections in early pregnancy

BACKGROUND: We demonstrated recently that adeno-associated virus-2 (AAV-2) DNA was detected significantly more frequently in placental trophoblast cells from cases of severe pre-eclampsia than from normal term deliveries. Here, we sought to determine if maternal AAV-2 infection early in pregnancy preceded adverse outcomes resulting from placental dysfunction. METHODS: We collected first trimester maternal serum samples and compared anti-AAV-2 IgM antibody levels (indicating primary infection or reactivation of latent AAV-2) between controls delivered at term (n = 106) and three groups of cases: spontaneous abortions (n = 34), spontaneous preterm deliveries (n = 24) and women with at least one outcome usually attributed to placental dysfunction, including pre-eclampsia, intrauterine growth restriction (IUGR) or stillbirth (n = 20). The seroprevalence of immunoglobulin G (IgG) antibodies against AAV-2 and IgM antibodies against viruses that promote AAV-2 replication [adenovirus and cytomegalovirus (CMV)] were also determined. RESULTS: First trimester maternal IgM seropositivity was 5.6 times more prevalent among pre-eclampsia/IUGR/stillbirth cases (P = 0.0004) and 7.6 times more prevalent among preterm deliveries (P < 0.0001) than among controls. CMV and adenovirus IgM antibodies and chronic AAV-2 infections (IgG seropositivity) were not associated with adverse pregnancy outcomes. CONCLUSIONS: Primary or reactivated AAV-2 infection (maternal IgM seropositivity) early in pregnancy was associated with adverse reproductive outcomes associated with placental dysfunction, including pre-eclampsia, stillbirth and spontaneous preterm delivery.
Abraham Jacobi, MD: father of american pediatrics and advocate for children’s health

Dr. Abraham Jacobi, often called the "father of American pediatrics," rose from humble beginnings in Germany to the highest positions in pediatrics and medicine in the United States. Most of the history of American pediatrics during the second half of the 19th century is reflected in Jacobi's writings and work. This article presents a brief overview of his life and character, focusing on the important roles he played in establishing the field of pediatrics as a distinct specialty and in advocating for children's health issues.
Comparative Physiology of Respiration in Aquatic Fungi

A comparative study of terminal respiration was undertaken in five genera of aquatic fungi in the Leptomitales. The cytochrome system in this group of fungi contained cytochrome a-a3 (605 nm), cytochrome c (551 nm), cytochrome b (557 nm), and cytochomo b (564 nm). A representative of each of three aerobic genera, Leptomitus, Apodachlya, and Sapromyces, had a total cytochrome content of about 2×10−10 mol/mg dry weight. An endogenous respiration rate of 21 μl O2 uptake/ (h × mg dry weight) at 21.7°C was found in Leptomitus and Apodmhlya and 14 in Sapromyces. The strain belonging to the fermenlative genus Mindeniella had approximately one-third of the total cytochrome content and one-third of the endogenous respiration rate observed in Leptomitus and Apodachlya. Mindeniella and Sapromyces contained less total cytochrome when grown under reduced oxygen tension than when grown in air. Only about one-half of the b-type cytochrome was redueible by endogenous substrates. Both cytochrome a3 and an unidentified pigment bound CO. The endogenous respiration of Leptomitus, Apodachlyo, and Sapromyces was strongly Inhibited by sodium cyanide, sodium azide, antimycin A, and sodium fluoroacetate.
Hysteretic response of supported drops during forced oscillations

Viscous liquid drops undergoing forced oscillations have been shown to exhibit hysteretic deformation under certain conditions both in experiments and by solution of simplified model equations that can only provide a qualitative description of their true response. The first hysteretic deformation results for oscillating pendant drops obtained by solving the full transient, nonlinear Navier–Stokes system are presented herein using a sweep procedure in which either the forcing amplitude A or frequency Ω is first increased and then decreased over a given range. The results show the emergence of turning-point bifurcations in the parameter space of drop deformation versus the swept parameter. For example, when a sweep is carried out by varying Ω while holding A fixed, the first turning point occurs at Ω ≡ Ωu as Ω is being increased and the second one occurs at Ω ≡ Ωl < Ωu as Ω is being decreased. The two turning points shift further from each other and toward lower values of the swept parameter as Reynolds number Re is increased. These turning points mark the ends of a hysteresis range within which the drop may attain either of two stable steady oscillatory states – limit cycles – as identified by two distinct solution branches. In the hysteresis range, one solution branch, referred to as the upper solution branch, is characterized by drops having larger maximum deformations compared to those on the other branch, referred to as the lower solution branch. Over the range Ωl [les ] Ω [les ] Ωu, the sweep procedure enables detection of the upper solution branch which cannot be found if initially static drops are set into oscillation as in previous studies of forced oscillations of supported and captive drops, or liquid bridges. The locations of the turning points and the associated jumps in drop response amplitudes observed at them are studied over the parameter ranges 0.05 [les ] A [les ] 0.125, 20 [les ] Re [les ] 40, and gravitational Bond number 0 [les ] G [les ] 1. Critical forcing amplitudes for onset of hysteresis are also determined for these Re values. The new findings have important ramifications in several practical applications. First, that Ωu − Ωl increases as Re increases overcomes the limitation which is inherent to the current practice of inferring the surface tension and/or viscosity of a bridge/drop liquid from measurement of its resonance frequencies (Chen & Tsamopoulos 1993; Mollot et al. 1993). Moreover, that the value of A for onset of hysteresis can be as low as 5% of the drop radius, or lower, has important implications for other free-surface flows such as coating flows.
Higher maternal plasma docosahexaenoic acid during pregnancy is associated with more mature neonatal sleep-state patterning

Background: The effect of docosahexaenoic acid (DHA) on the developing fetal central nervous system (CNS) and related functional outcomes in infancy remain unexplored. Sleep and wake states of newborns provide a tool for assessing the functional integrity of the CNS. Objective: We investigated whether CNS integrity in newborns, measured with sleep recordings, was associated with maternal concentrations of long-chain polyunsaturated fatty acids, especially DHA. Design: Plasma phospholipid fatty acid concentrations were measured in 17 women at parturition. On postpartum day 1 (P1) and day 2 (P2), a pressure-sensitive pad under the infants’ bedding recorded body movements and respiratory patterns to measure sleep and wake states. Results: Maternal plasma phospholipid DHA ranged from 1.91% to 4.5% by wt of total fatty acids. On the basis of previously published data and the median DHA concentration, the women were divided into 2 groups: high DHA (> 3.0% by wt of total fatty acids) and low DHA (≤ 3.0% by wt of total fatty acids). Infants of high-DHA mothers had a significantly lower ratio of active sleep (AS) to quiet sleep (QS) and less AS than did infants of low-DHA mothers. Furthermore, the former infants had less sleep-wake transition and more wakefulness on P2. Correlations of maternal DHA status with infant sleep states were consistent with these data. Also, the ratio of maternal n� 6 to n� 3 fatty acids on P1 was inversely associated with QS and positively associated with arousals in QS. On P2, maternal n� 6:n� 3 was positively associated with AS, sleep-wake transition, and AS:QS. Conclusion: The sleep patterns of infants born to mothers with higher plasma phospholipid DHA suggest greater CNS maturity. Am J Clin Nutr 2002;76:608‐13.
Reciprocal inheritance of centrosomes in the parthenogenetic Hymenopteran Nasonia vitripennis.

Background: In the majority of animals, the centrosome — the microtubuleorganizing center of the cell — is assembled from components of both the sperm and the egg. How the males of the insect order Hymenoptera acquire centrosomes is a mystery, as they originate from virgin birth. Results: To address this issue, we observed centrosome, spindle and nuclear behavior in real time during early development in the parthenogenetic hymenopteran Nasonia vitripennis. Female meiosis was identical in unfertilized eggs. Centrosomes were assembled before the first mitotic division but were inherited differently in unfertilized and fertilized eggs. In both, large numbers of asters appeared at the cortex of the egg after completion of meiosis. In unfertilized eggs, the asters migrated inwards and two of them became stably associated with the female pronucleus and the remaining cytoplasmic asters rapidly disappeared. In fertilized eggs, the Nasonia sperm brought in paternally derived centrosomes, similar to Drosophila melanogaster. At pronuclear fusion, the diploid zygotic nucleus was associated only with paternally derived centrosomes. None of the cytoplasmic asters associated with the zygotic nucleus and, as in unfertilized eggs, they rapidly degenerated. Conclusions: Selection and migration of the female pronucleus is independent of the sperm and its aster. Unfertilized male eggs inherit maternal centrosomes whereas fertilized female eggs inherit paternal centrosomes. This is the first system described in which centrosomes are reciprocally inherited. The results suggest the existence of a previously undescribed mechanism for regulating centrosome number in the early embryo.
A context-blocks model for identifying clinical relationships in patient records

Patient records contain valuable information regarding explanation of diagnosis, progression of disease, prescription and/or effectiveness of treatment, and more. Automatic recognition of clinically important concepts and the identification of relationships between those concepts in patient records are preliminary steps for many important applications in medical informatics, ranging from quality of care to hypothesis generation. In this work we describe an approach that facilitates the automatic recognition of eight relationships defined between medical problems, treatments and tests. Unlike the traditional bag-of-words representation, in this work, we represent a relationship with a scheme of five distinct context-blocks determined by the position of concepts in the text. As a preliminary step to relationship recognition, and in order to provide an end-to-end system, we also addressed the automatic extraction of medical problems, treatments and tests. Our approach combined the outcome of a statistical model for concept recognition and simple natural language processing features in a conditional random fields model. A set of 826 patient records from the 4th i2b2 challenge was used for training and evaluating the system. Results show that our concept recognition system achieved an F-measure of 0.870 for exact span concept detection. Moreover the context-block representation of relationships was more successful (F-Measure = 0.775) at identifying relationships than bag-of-words (F-Measure = 0.402). Most importantly, the performance of the end-to-end system of relationship extraction using automatically extracted concepts (F-Measure = 0.704) was comparable to that obtained using manually annotated concepts (F-Measure = 0.711), and their difference was not statistically significant. We extracted important clinical relationships from text in an automated manner, starting with concept recognition, and ending with relationship identification. The advantage of the context-blocks representation scheme was the correct management of word position information, which may be critical in identifying certain relationships. Our results may serve as benchmark for comparison to other systems developed on i2b2 challenge data. Finally, our system may serve as a preliminary step for other discovery tasks in medical informatics.
Nation, Region, and Globe: Alternative Definitions of Place in World History

This chapter begins in the recognition of the importance of “world history” and considers some of the current challenges this field faces. It considers several important contributions to the field that illuminate the value of fresh approaches: James Scott’s construction of “Zomia”, Emmanuel Todd’s historicization of “France” as a nation, Bin Wong and Kenneth Pomeranz’s new approach to Eurasian economic history, and Victor Lieberman’s analysis of the strange synchrony between Southeast Asia and Western Europe over a millennium of political development. The essay concludes with several historiographical maxims: avoid eurocentrism, expect variation, look for mechanisms of inter-connection, avoid capture by “nation-state” concepts, and pay attention to different schemes of historical time.
A "Flying-Adder" frequency synthesis architecture of reducing VCO stages

The "Flying-Adder" architecture is a frequency and phase synthesis technique that is based on a voltage-controlled oscillator (VCO) of multiple delay stages. Since the invention of this architecture, various improvements have been made during many implementations of this technique. One of the remaining issues is to reduce the number of delay stages inside the VCO for the benefit of low power consumption and easy design/layout implementation. This paper presents a modified version of the architecture, by utilizing the scalability presented by Xiu and You, 2002, to achieve this goal. The modified architecture can also be used to improve the number of synthesizable frequencies. The tradeoff for this architecture of reduced-delay-stage VCO is the circuit speed
X-ray microanalysis of cell elements in normal and cystic fibrosis jejunum: Evidence for chloride secretion in villi

Abstract BACKGROUND & AIMS: Cystic fibrosis transmembrane conductance regulator (CFTR) is an adenosine 3',5'-cyclic monophosphate-dependent chloride channel that is defective in cystic fibrosis. The aims of this study were to determine if defective apical chloride secretion in the intestine of patients with cystic fibrosis alters the intracellular electrolyte milieu and to examine the geographical localization of CFTR in the normal intestine. METHODS: The content of intracellular elements was assessed in cryosections using energy-dispersive x-ray microanalysis, and CFTR was identified by immunocytochemistry using commercially available antibodies. RESULTS: Cystic fibrosis jejunum had a significantly lower Na+ content, higher K+ and Cl- content, and higher potassium/phosphorus ratio in both villus and crypt regions. Incubation of normal jejunum with the phosphodiesterase inhibitor 3- isobutyl-1-methyl-xanthine (300 mumol/L) resulted in decreased K+ and Cl- content in both crypt and villus regions, indicative of Cl- secretion. CFTR was identified on the surface of normal villus and crypt enterocytes but not in cystic fibrosis samples. CONCLUSIONS: Defective apical chloride channels in cystic fibrosis result in alterations in the intracellular electrolyte milieu. The microanalysis observations and immunocytochemical studies imply a role for villus enterocytes in human intestinal chloride secretion. (Gastroenterology 1996 Feb;110(2):411-8)
Anatomic Considerations of the Penis, Lymphatic Drainage, and Biopsy of the Sentinel Node

This article reviews anatomic considerations in penile and urethral surgery, with a particular emphasis on lymphatic anatomy. The historical evolution of techniques to reduce the unnecessary use and operative morbidity of inguinofemoral lymph node dissection are reviewed, with an emphasis on sentinel node (SN) biopsy and dynamic SN biopsy techniques.
Analysis of sequence-specific binding activity of cis-elements in human thymidine kinase gene promoter during G1/S phase transition

Expression of thymidine kinase (TK) gene in normal human diploid cells is both cell cycle and age dependent and appears to be transcriptionally regulated. Several studies have indicated that the G1/S control sequence may reside within the region of about 130 bp upstream of the transcription initiation site. We have previously shown that a trans-acting factor, CBP/tk (CCAAT binding protein for TK gene), binds to either one of the two inverted CCAAT boxes in a cell cycle- and age-dependent manner (Pang and Chen, 1993, J. Biol. Chem., 268:2909–2916). An upstream 25 bp fragment (−109/−84), containing both Yi-like and E2F-like binding sites, has recently been proposed to be essential for the G1/S regulation of human TK gene. To assess the contribution of various cis-elements in human TK promoter to the G1/S regulation, we have examined the binding activity of these cis-elements in the nuclear extracts derived from human IMR-90 cells at low passage number. Our results indicated that no binding activity could be detected using either the 25 bp fragment (−109/−94) or the authentic Yi sequence. However, Yi binding activity was observed in SV-40 transformed IMR-90 cells. In contrast, the 28 bp fragment (−91/−64) that contains the distal inverted CCAAT box exhibited a strong binding in serum-stimulated young IMR-90 cells. The binding of CBP/tk to the 28 bp fragment was abolished by a single base mutation in the CCAAT box. The CBP/tk binding of the 28 bp fragment could not be displaced by either the 25 bp fragment or the authentic Yi element. A deletion of the 5′-flanking region of the 28 bp fragment up to 5 bases also abolished the binding activity. The CBP/tk binding in IMR-90 cells was supershifted by antiserum against NF-Ya, but not by antiserum made against p107, pRb, cyclin A, p33cdk2, or p34cdc2. Taken together, our results suggest that the G1/S regulatory cis-element in human TK promoter may be confined only to CBP/tk binding sites. © 1995 Wiley-Liss, Inc.