cssi/SciSciGPT-SciSciNet huggingface dataset:
Xenopus oocyte maturation: new lessons from a good egg.

Fully grown Xenopus oocytes can remain in their immature state essentially indefinitely, or, in response to the steroid hormone progesterone, can be induced to develop into fertilizable eggs. This process is termed oocyte maturation. Oocyte maturation is initiated by a novel plasma membrane steroid hormone receptor. Progesterone brings about inhibition of adenylate cyclase and activation of the Mos/MEK1/p42 MAP kinase cascade, which ultimately brings about the activation of the universal M phase trigger Cdc2/cyclin B. Oocyte maturation provides an interesting example of how signaling cascades entrain the cell cycle clock to environmental changes.
Tp* Rhenium(V) Oxo−Halide, −Hydride, −Alkyl, −Phenyl, and −Alkoxide Complexes: Syntheses and Oxidations

Rhenium−oxo complexes with the hydridotris(3,5-dimethyl-1-pyrazolyl)borate (Tp*) ligand are described. Halide complexes Tp*Re(O)X(Cl) (X = Cl, I) are prepared by treatment of Tp*Re(O)(OH)Cl with HX. Reaction of Tp*Re(O)Cl2 (3) with 1 or 2 equiv of LiPh/ZnCl2 or Et2Zn produces the corresponding oxo−aryl and oxo−alkyl complexes Tp*Re(O)(Ph)Cl, Tp*Re(O)(Ph)2, and Tp*Re(O)(Et)Cl. Alkoxide complexes Tp*Re(O)(OR)Cl and Tp*Re(O)(OR)2 are prepared from 3 and ROH, PhOH, or catechol. Triflate complexes Tp*Re(O)X(OTf) (X = halide, H, Et, Ph, OEt, OPh) have been prepared by halide metathesis with AgOTf or by alkoxide metathesis with Me3SiOTf. Hydride complexes Tp*Re(O)(H)X (X = Cl, H) are generated from the corresponding alkoxide complexes with BH3·THF. Oxidation of Tp*Re(O)Ph(OTf) with Me2SO gives a phenoxide complex, and oxidation of Tp*Re(O)Et(OTf) with pyridine N-oxide gives acetaldehyde. Both reactions are similar to oxidations of related Tp compounds. Tp*Re(O)H(OTf) is oxidized by either reagent to Tp*Re(O)3, w...
879 NEUROBLASTOMA IN INFANTS: WHEN IS THERAPY NECESSARY?

From 1974 through 1983, 19 new neuroblastoma patients less than one year of age were seen at our institution. We have followed 17 of these patients for 18-130 months. Primary tumor site in this group was adrenal (8), mediastinum (6), pelvis (2) or retroperitoneum (1). Staging by Evans' criteria was I (1), II (4), III (5), IV (6) or IV-S (1). Three stage IV patients would have been IV-S except for distant node involvement. Only 1 patient had bony metastases at diagnosis. Of these 17 patients, 11 had complete excision of primary tumor, 4 had subtotal resection, 1 had biopsy only and 1 had biopsy of metastatic disease. Two patients had progession of disease following the primary surgical procedure, 1 to skin and 1 to bone. Both patients with bony metastases were treated with aggressive multiagent chemotherapy; both died with progressive disease. The other 15 patients are all alive and disease-free with follow-up of 18+ to 130+ months. Thirteen of these 15 patients, including many with widespread metastatic disease and large primary tumors, received no therapy other than the initial surgical resection or biopsy. Two patients received 2500 rad to the primary tumor site and 1 received cyclophosphamide as a single agent. These observations suggest that many infants with neuroblastoma without skeletal metastases will undergo spontaneous regression of tumor, and should be followed expectantly without further therapy.
Alumina-tantalum composite for femoral head applications in total hip arthroplasty

Abstract Dense composite laminates of alumina (Al 2 O 3 ) and tantalum (Ta) were fabricated by hot pressing and tested in vitro for potential use as a femoral head material in total hip arthroplasty (THA). Al 2 O 3 –Ta composite laminates hot pressed at 1450 °C and 1650 °C had flexural strengths of 940 ± 180 MPa and 1090 ± 340 MPa, respectively, which were far larger than the values of 420 ± 140 MPa and 400 ± 130 MPa for Al 2 O 3 hot pressed at 1450 °C and 1650 °C, respectively. The interfacial shear strength, determined by a double-notched specimen test, was 310 ± 80 MPa for the composite laminate hot pressed at 1650 °C, indicating strong interfacial bonding between Al 2 O 3 and Ta. Scanning electron microscopy (SEM), energy dispersive X-ray (EDS) analysis, and X-ray mapping of polished sections of the hot-pressed laminates showed the presence of an interfacial region formed presumably by diffusion of O (at 1450 °C) or O and Al (1650 °C) from Al 2 O 3 into Ta. Composite femoral heads of Al 2 O 3 and Ta could combine the low wear of an Al 2 O 3 articulating surface with the safety of a ductile metal femoral head.
Cyclo-(-l-prolyl-l-valinyl-) from Burkholderia thailandensis MSMB43.

The title compound [systematic name: (3S,8aS)-3-isopropyl­hexa­hydro­pyrrolo­[1,2-a]pyrazine-1,4-dione], C10H16N2O2,, is a newly isolated cyclic dipeptide from Burkholderia thailandensis MSMB43. There are two independent mol­ecules in the asymmetric unit. Two C atoms and their attached H atoms in the five-membered ring of one of the mol­ecules are disordered over two sets of sites in a 0.715 (5):0.285 (5) ratio. The two independent mol­ecules have the same configuration and the absolute configurations of the chiral centers were determined based on the observation of anomalous dispersion. In the crystal, two types of N—H⋯O hydrogen bonds link pairs of independent mol­ecules.
Rarefactions and large time behavior for parabolic equations and monotone schemes

We consider the large time behavior of monotone semigroups associated with degenerate parabolic equations and monotone difference schemes. For an appropriate class of initial data the solution is shown to converge to rarefaction waves at a determined asymptotic rate.
NaCl preference increases during pregnancy and lactation: assessment using brief access tests

Pregnancy and lactation are characterized by increases in NaCl intake, as determined by long-term consumption tests, which cannot examine the relative contribution of taste and postingestive factors to this phenomenon. Consequently, in this study, changes in NaCl preference during pregnancy and lactation were studied in nulliparous Long-Evans rats using a brief access test (lickometer). In Experiment 1, rats were maintained on a Na(+)-adequate diet (0.03% Na(+)), habituated to lickometer testing, and subsequently assessed during pregnancy and lactation with three 30-s exposures to each of seven taste solutions: 0.075 M sucrose (base), 0.089 M NaCl in base, 0.158 M NaCl in base, 0.281 M NaCl in base, 0.5 M NaCl in base, 0.158 M NaCl and 0.281 M NaCl. Results indicated higher lick rates to the 0.5 M NaCl in base, 0.158 M NaCl and 0.281 M NaCl solutions during late pregnancy and late lactation (Day 13 and beyond). In Experiment 2, a comparison of two diets differing in sodium content (0.03% vs. 0.3% Na(+)) determined that these changes in NaCl preference during pregnancy and lactation were unrelated to dietary sodium. Thus, the apparent increase in NaCl preference during pregnancy and lactation, independent of dietary sodium, suggests that this change in preference is not in response to physiological sodium need.
Spreading at the teflon / oil / water / air interfaces

Abstract The thermodynamic criterion for whether one liquid can spread and displace a second liquid from a solid is given by the spreading coefficient, S L 1 SL 2 , a positive value indicating that spreading will tend to occur. For the hydrophobic solid Teflon (PTFE), γ S = 22 ergs/cm 2 , and oils such as tetradecane, hexadecane, tricresyl phosphate, and several mineral oils ( γ o ∼ 28–30 ergs/cm 2 ) have negative spreading coefficients at the Teflon/oil/water interface. Therefore, these oils would be expected not to displace water in such systems. However, it was observed in this laboratory that these oils could displace water if a four-phase Teflon/oil/water/air interface was established. Such a four-phase contact was achieved in several ways, one of which was to advance symmetrically a film of water up to an oil drop placed on the Teflon surface; another was to decrease the water height below the top of the oil drop, at which point the water layer automatically receded. This observed spreading at the four-phase Teflon/oil/water/air interface is not at odds with the negative values of the spreading coefficient of these oils. The spreading coefficient refers to a specific state characterized by a three-phase soild/oil/water interface and is not applicable to spreading at a four-phase interface.
Labeling of bovine corpus luteal plasma membrane human chorionic gonadotropin or luteinizing hormone (hCGLH) receptor and its purification and properties

Abstract A method has been developed for labeling receptors for human chorionic gonadotropin or luteinizing hormone ( hCG LH ) present on bovine corpus luteal plasma membranes. It consists of four steps: (a) protection of the receptor by treating the plasma membranes with hCG; (b) iodination of the membranes with KI using glucose, glucose oxidase, and lactoperoxidase; (c) unmasking the receptor with either 2 m NaCl, 1 m guanidine hydrochloride, or rabbit anti-hCG; and (d) reiodination of the membranes using Na131I. After solubilization by successive treatments with Sepharose-concanavalin A and Sepharose-hCG and finally by preparative disc electrophoresis, the resulting purified receptor after electrophoresis in polyacrylamide gel showed a single radioactive band containing receptor activity. This highly purified receptor is fairly stable and retains its hormonal specificity, binding affinity, and pH optimum. It was observed that the receptor alone or as a complex with the hormone tends to aggregate. The receptorhormone complex does not dissociate during polyacrylamide-gel electrophoresis.
Personality structure and aging style

Abstract In this article we argue that different patterns of aging can be best understood if we shift the emphasis from looking at discrete characteristics to an emphasis on the whole individual. In this way aging becomes the integration of past experience and present events in the framework of a continuous self. We argue that different Styles of Aging derive from specific personality configurations. Using five personality types, as defined in axis II of DSM-III-R, we illustrate how the elderly cope with the constraints of old age, create an aging identity and respond to life events in ways that fit their personality styles. We conclude by suggesting new research questions.
Fuzzy traversability index: A new concept for terrain‐based navigation

Fuzzy Traversability Index is introduced in this paper as a new and simple measure for quantifying the ease of traversal of natural terrains by field mobile robots. This index provides a simple means for incorporating the terrain quality data into the robot navigation strategy and is used for terrain-based navigation of field mobile robots. The Traversability Index is expressed by fuzzy sets that quantify the suitability of the terrain for traversal based on its geometrical and physical properties, such as slope, roughness, and hardness. This descriptive representation of terrain traversability in a natural language using linguistic variables and conditional statements is easily comprehensible, more appealing, and closer to human intuition than a mathematical formulation of traversability. A set of fuzzy navigation rules is developed using the Fuzzy Traversability Index to guide the robot toward the safest and the most traversable terrain. In addition, another set of fuzzy rules is developed to drive the robot from its initial position to a user-specified goal position. These two rule sets are integrated in a two-stage procedure for autonomous robot navigation without a priori map-based knowledge about the environment. In the first stage, the traverse-terrain and seek-goal rule sets make their individual, independent recommendations for robot turn and move commands. In the second stage, these recommendations are integrated by using appropriate weighting factors to generate the combined, coordinated recommendation for the robot navigation based on the robot status. Three simulation studies are presented to demonstrate the capability of the mobile robot to reach the goal safely while avoiding impassable terrains. ©2000 John Wiley & Sons, Inc.
Spectral radius bounds for positive matrices with applications to networked control systems over fading channels

Upper and lower bounds for spectral radius of positive matrices are derived, and are shown to be tight. These bounds are characterized by the determinant and trace of some related matrix, and they find applications in networked control systems (NCS) over fading channels. Results are obtained for the relation between mean-square (MS) stabilization and standard ℋ 2 optimal control, and for the MS stabilizability condition under state feedback control. An encoding and decoding matrix pair is introduced to help design the state feedback controllers, when the MS stabilizability condition holds true.
Stoichiometry of combined aerobic and methanogenic COD transformation

Under oxygen-limited conditions, both aerobic respiration and methanogenesis were accomplished by a mixed culture developed from a municipal anaerobic digester sludge and maintained under batch conditions. Oxygen-limited systems were maintained for over 130 days, producing methane and biomass while consuming oxygen under stable conditions, with chemical oxygen demand (COD) removal averaging 92%. Typically, the dissolved oxygen in the culture medium was zero. However, short periods of greater-than-zero dissolved oxygen were evident. In this case, methanogens were not killed by dissolved oxygen, but may have been inhibited during oxic periods. Electron equivalent balances were employed to construct stoichiometric equations for propionate- and ethanol-fed cultures that received enough oxygen to oxidize approximately 0, 10, and 30% of the added substrate. Oxygen-limited cultures exhibited maximum yield coefficients (Y) of between 0.06 and 0.11 g volatile suspended solids per gram COD. These values are more typical of methanogenic, rather than aerobic systems. Under some conditions, it may be possible to achieve low COD values associated with aerobic systems and produce the minimum waste biomass associated with methanogenic systems in a single-sludge, oxygen-limited process. Other possible benefits of methanogenic, oxygen-limited systems include: degradation of specific organics and mixtures of organics that proceed through both reductive and oxidative biological reactions; degradation of specific organics through cometabolic, methanotrophic reactions; concurrent nitrification and denitrification; and description of natural systems under oxygen-limited conditions.
Tools for Improved Social Interacting

Tools for Improved Social Interacting is a series of wearable devices---including the Anti-Day-dreaming Device, Happiness Hat, and Body Contact Training Suit---that use sensors to condition the behavior of the wearer to better adapt to expected social behaviors. The work explores the potential for technology to shape how we think, feel, and act. It also questions our social expectations, attempting to better understand their function and worth.
Effects of Ligand Composition on the Oxidative Carbonylation of Toluene to Toluic Acid Catalyzed by Rh(III) Complexes

Experimental and theoretical studies were conducted to investigate the influence of anionic ligands (e.g., CF3COO−, CH3SO3−) on the catalytic activity and selectivity of Rh(III) in the oxidative carbonylation of toluene to toluic acid. The catalyst activity was found to pass through a maximum as the pKa of the conjugate Bronsted acid decreases from 4.63 to −2.00, with the maximum activity occurring at pKa = 0.35, corresponding to CClF2COOH. The theoretical analysis showed that the strength of toluene coordination increases with decreasing basicity of the anion (i.e., decreasing pKa of the corresponding acid). In contrast, the activation barrier for C−H activation increases with decreasing ligand pKa. The experimentally observed effect of anion composition on catalyst activity can be explained using calculations of the apparent rate coefficient for toluene activation based on density functional theory and transition state theory. The ratio of p- to m-toluic acid formed increases with decreasing acid pKa an...
Agent-Based Modeling to Inform Online Community Design: Impact of Topical Breadth, Message Volume, and Discussion Moderation on Member Commitment and Contribution

The design of complex social systems, such as online communities, requires the consideration of many parameters, a practice at odds with social science research that focuses on the effects of a small set of variables. In this article, we show how synthesizing insights from multiple, narrowly focused social science theories in an agent-based model helps us understand factors that lead to the success of online communities. The agent-based model combines insights from theories related to collective effort, information overload, social identity, and interpersonal attraction to predict motivations for online community participation. We conducted virtual experiments to develop hypotheses around three design decisions about how to orchestrate an online community—topical breadth, message volume, and discussion moderation—and the trade-offs involved in making these decisions. The simulation experiments suggest that broad topics and high message volume can lead to higher member commitment. Personalized moderation o...
The effects of differential attention and time out on child noncompliance

This project evaluated the effects of differential attention and time out on child noncompliance in 32 noncompliant, clinic-referred, preschool children. Subjects were assessed under baseline conditions and then under one of four experimental conditions: attention, time out, attention plus time out, or control. The results indicated that only the time out contributed to compliance acquistion.
A novel nano-injector-based single-photon infrared detector

We present a novel single photon detector based on a nano-injector. This method, in principle, is capable of single photon detection at room temperature at λ~1.7 μm. Also, the process is not based on avalanche multiplication, and hence the device has no excess noise. Moreover, the device can cover a wide range of wavelengths from UV to mid-infrared, since the detection and amplification processes are completely decoupled and delocalized. Unlike avalanche-based detectors, this device operates at a very low bias that makes it possible to produce large 2D arrays with a good uniformity.
Estrogenicity of selected biphenyls evaluated using a recombinant yeast assay

The estrogenic activity of biphenyl and 4-hydroxylatedderivatives with varied levels of chloro- and/or hydroxyl substitution was measured in a Saccharomyces cerevisiae-based lac-Z (β-galactosidase) reporter assay. β-Galactosidase activity was compared with competitive binding to soluble mouse uterine estrogen receptor protein. The comparison of relative potency for biphenyls hydroxylated on one ring and chlorinated on the other ring (n = 5) revealed excellent correlation between the two systems (r2 = 0.995). However, estrogenicities of biphenyls hydroxylated and chlorinated on the same ring were not in agreement. Although weak ligand binding was demonstrated for these compounds, β-galactosidase activity was not observed. Rather, these compounds were shown to be cytotoxic to yeast. The results of this study further support the hypothesis that both an unhindered phenolic ring and molecular symmetry are structural features associated with estrogenicity.
The role of culture in comics of the quotidian

Studies of the quotidian often start from a social sciences perspective that daily life is made up of routine practices and ingrained assumptions. This is also found in studies of literature, art and economics. The premise of the quotidian, however, must be examined through a lens of culture. This essay explores how the notion of the quotidian in comics rests on culture, which in turn comprises various nexus of practice. Drawing evidence from Exit Wounds (by Rutu Modan) and Questionable Content (by Jeph Jacques), the essay extends the notion of the quotidian from a specific reference to ‘slice of life comics’ to a broader assumption that all comics articulate a vision of the quotidian. The analysis points to the conclusion that the culture of the world inside comics must be accounted for in most any attempt to understand the quotidian in comics.
Comments on 'Trade policies in the U.S. automobile industry', by Penny Koujianou Goldberg

Abstract This is a paper on an important and timely topic and it represents a substantial improvement over much of the existing literature on the effects of trade policy in the U.S. automobile market. In particular, the use of consumer level data provided by the Consumer Expenditure Survey (CES) is a clever and useful approach to a problem frequently plagued by too little data. It is apparent that a great deal of time and effort have gone into this project. When I first discussed this paper, I noted that I was troubled by four issues. These were the estimation of demand elasticities, consumer welfare, the treatment of direct foreign investment by Japanese firms, and the modelling of the North American Free Trade Agreement (NAFTA). I am still concerned by these issues, and I will discuss them in turn.
Entropically Driven Formation of Hierarchically Ordered Nanocomposites

Using theoretical models, we undertake the first investigation into the rich behavior that emerges when binary particle mixtures are blended with microphase-separating copolymers. We isolate an example of coupled self-assembly in such materials, where the system undergoes a nanoscale ordering of the particles along with a phase transformation in the copolymer matrix. Furthermore, the self-assembly is driven by entropic effects involving all the different components. The results reveal that entropy can be exploited to create highly ordered nanocomposites with potentially unique electronic and photonic properties.
Fully dynamic algorithms for chordal graphs and split graphs

We present the first dynamic algorithm that maintains a clique tree representation of a chordal graph and supports the following operations: (1) query whether deleting or inserting an arbitrary edge preserves chordality; and (2) delete or insert an arbitrary edge, provided it preserves chordality. We give two implementations. In the first, each operation runs in O(n) time, where n is the number of vertices. In the second, an insertion query runs in O(log2n) time, an insertion in O(n) time, a deletion query in O(n) time, and a deletion in O(n log n) time. We also present a data structure that allows a deletion query to run in O(√m) time in either implementation, where m is the current number of edges. Updating this data structure after a deletion or insertion requires O(m) time.We also present a very simple dynamic algorithm that supports each of the following operations in O(1) time on a general graph: (1) query whether the graph is split, and (2) delete or insert an arbitrary edge.
Disorder induced cluster formation near first-order phase transitions in electronic systems: Importance of long-range Coulomb interactions

We discuss the effects of fluctuations of the local density of charged dopants near a first-order phase transition in electronic systems that is driven by a change of the charge carrier density controlled by the doping level. Using a generalization of the Imry-Ma argument, we find that the first-order transition is rounded by disorder at or below the lower critical dimension ${d}_{c}=3$ when at least one of the two phases has no screening ability. The increase of ${d}_{c}$ from 2 (as in the random field Ising model) to 3 is due to the long-range nature of the Coulomb interaction. This result suggests that large clusters of both phases will appear near such transitions due to disorder in both two and three dimensions. Possible implications of our results on manganites and underdoped cuprates will be discussed.
Anxiety-related constructs mediate the relation between age and health anxiety.

Objective: Few studies have examined health anxiety in older adults, and it is unknown which factors account for age-related differences in health anxiety. Given similarities between health anxiety and the anxiety disorders, anxiety-related constructs, including anxiety sensitivity, intolerance of uncertainty, emotion regulation, and anxiety control, were examined as mediators of the relation between age (older vs. young adults) and health anxiety. Methods: Eighty-six older adults aged 60 and older and 117 young adults aged 18 to 30 completed several self-report measures of health anxiety and anxiety-related constructs. Results: Young adults reported higher levels of health anxiety than older adults. Anxiety sensitivity and intolerance of uncertainty partially mediated the relation between age and health anxiety. Perceived anxiety control, reappraisal, and suppression did not mediate the relation between age and health anxiety. Conclusions: Anxiety sensitivity and intolerance of uncertainty are predisposi...
Broken-symmetry states and divergent resistance in suspended bilayer graphene

The presence of disorder makes it difficult to determine the intrinsic properties of graphene in its ideal form. Measurements of high-quality bilayer graphene flakes suspended above a substrate identify the persistence of quantum Hall behaviour at magnetic fields an order of magnitude lower than seen before, and previously unseen symmetry breaking of the lowest Landau level is also observed. Mono- and bilayer graphene have generated tremendous excitement owing to their unique and potentially useful electronic properties1. Suspending single-layer graphene flakes above the substrate2,3 has been shown to greatly improve sample quality, yielding high-mobility devices with little charge inhomogeneity. Here we report the fabrication of suspended bilayer graphene devices with very little disorder. We observe quantum Hall states that are fully quantized at a magnetic field of 0.2 T, as well as broken-symmetry states at intermediate filling factors ν=0, ±1, ±2 and ±3. In the ν=0 state, the devices show extremely high magnetoresistance that scales as magnetic field divided by temperature. This resistance is predominantly affected by the perpendicular component of the applied field, and the extracted energy gap is significantly larger than expected for Zeeman splitting. These findings indicate that the broken-symmetry states arise from many-body interactions and underscore the important part that Coulomb interactions play in bilayer graphene.
Research Aircraft Measurements of Jet Stream Geostrophic and Ageostrophic Winds

Abstract Radar altimeter and inertial navigation wind velocity measurements from research aircraft are shown to give the ageostrophic wind velocity distribution within a jet stream system near the tropopause. Results from one case study reveal cross-height-contour ageostrophic winds exceeding 20 m s−1, and centripetal-acceleration-induced ageostrophic winds approaching 100 m s−1 in the exit region of a jet streak which has entered into the trough region of a synoptic wave. Diagnostic calculations are made of the horizontal velocity divergence and the geostrophic and ageostrophic components of the observed wind velocity acceleration. The results suggest caution in the application of near-straight jet-streak dynamics and the geostrophic momentum approximation to jet-streak systems embedded within large-amplitude synoptic wave regimes.
Teamwork Preparing Students for the New Reality

This article describes a team-based project developed for undergraduate students in both business communication and business statistics classes in a small, midwestern college. More than 94% of the ...
Using a laboratory computer for identification of nonlinear behavioral and electrophysiological systems

A system for mathematically identifying unknown nonlinear systems based upon Wiener kernels and G-functionals is presented as an example of the sophisticated analyses of electrophysiological and behavioral data made possible by the introduction of powerful digital computers to the laboratory environment. The applicability of these methods to a wide variety of systems is emphasized. By measuring the response of the unknown system to appropriate white noise stimulation, data may be obtained which are sufficient for the characterization of the system under test. The only restrictions upon the unknown system is that it be approximately stationary during the period of measurement and that its output depend upon its input in the finite past. Various pretests to evaluate the applicability of the method are presented. Simple FORTRAN programs that clarify the methods of computation are given for the preprocessing of data, the analysis of lower-order kernels, the synthesis of system response from the computed kernels, and the computation of the proportion of the variance in the systems output which is accounted for by the kernels zero, one, and two. These programs may be implemented on a digital laboratory computer of moderate size. Analysis may be performed either on-line or after data collection, depending upon the temporal characteristics of the system under test. This method represents one of the few analytical techniques presently available for the characterization of both linear and nonlinear systems. For this reason, it constitutes a uniquely powerful tool for many branches of psychology. Successful applications of this method to electrophysiological and behavioral data are mentioned. Limiting factors in the use of Wiener kernel analysis are also discussed.
Is echocardiography or magnetic resonance imaging superior for precoarctation angioplasty evaluation

We compared the dimensions of the aorta obtained by two-dimensional transthoracic echocardiography (echo) (median, 2.5 mo preangioplasty) and magnetic resonance imaging (MRI) (median, 4.2 mo preangioplasty) to those obtained by angiography (cath) in 13 patients (age, 7.7 +/- 1.6 yr; mean +/- SEM) who underwent evaluation for coarctation balloon angioplasty between April 1993-January 1996. Echo measurements were obtained from the suprasternal and subcostal sagittal planes, MRI measurements from axial and sagittal oblique views, and cath measurements from the straight lateral or oblique views. Measurements of the diameters of the aortic isthmus, coarctation, descending aorta at the diaphragm, and isthmus length were made by all three modalities. Presence of aorto-aortic collaterals was determined, and the coarctation length was delineated. Investigators were blinded to other measurement data prior to statistical analysis. Data analysis by repeated analysis of variance (ANOVA) and Student-Newman-Keuls testing revealed no statistically significant difference between systolic pressure gradient by clinical examination (32.2 +/- 5.9 mm Hg), peak instantaneous Doppler evaluation (37.5 +/- 2.9 mm Hg), or preangioplasty systolic pressure gradient (32.1 +/- 3.3 mm Hg). With the exception of measurements of the descending aorta (echo, 11.7 +/- 0.9 mm vs. MRI, 13.3 +/- 0.8 mm vs. cath, 14.0 +/- 1.3 mm; P = 0.04), there was no statistically significant difference in dimensions of the aortic isthmus (9.2 +/- 0.6 mm vs. 10.5 +/- 0.9 mm vs. 10.8 +/- 0.9 mm), coarctation site diameter (4.8 +/- 0.6 mm vs. 5.6 +/- 0.9 mm vs. 5.3 +/- 0.8 mm), or isthmus length (12.4 +/- 2.1 mm vs. 12.1 +/- 2.2 mm vs. 10.9 +/- 1.7 mm). The correlation coefficients derived from comparisons of MRI vs. cath to echo vs. cath were similar for all dimensions except for isthmus length (P < 0.01). MRI demonstrated aorto-aortic collaterals more frequently than echo, while echocardiography better demonstrated cardiac function and intracardiac anomalies. Both modalities detected the single patient with a long segment coarctation. We conclude that echocardiography and MRI provide similar definition of the coarcted thoracic aorta, and either test may be individually advantageous in specific clinical situations.
Magnetic resonance imaging-guided focused laser interstitial thermal therapy for subinsular metastatic adenocarcinoma: technical case report.

Background and importance To describe the novel use of the AutoLITT System (Monteris Medical, Winnipeg, Manitoba, Canada) for focused laser interstitial thermal therapy (LITT) with intraoperative magnetic resonance imaging (MRI) and stereotactic image guidance for the treatment of metastatic adenocarcinoma in the left insula. Clinical presentation The patient was a 61-year-old right-handed man with a history of metastatic adenocarcinoma of the colon. He had previously undergone resection of multiple lesions, Gamma Knife radiosurgery, and whole-brain radiation. Despite treatment of a left insular tumor, serial imaging revealed that the lesion continued to enlarge. Given the refractory nature of this tumor to radiation and the deep-seated location, the patient elected to undergo LITT treatment. The center of the lesion and entry point on the scalp were identified with STEALTH (Medtronic, Memphis, Tennessee) image-guided navigation. The AXiiiS Stereotactic Miniframe (Monteris Medical) for the LITT system was secured onto the skull, and a trajectory was defined to achieve access to the centroid of the tumor. After a burr hole was made, a gadolinium template probe was inserted into the AXiiiS base. The trajectory was confirmed via an intraoperative MRI, and the LITT probe driver was attached to the base and CO2-cooled, side-firing laser LITT probe. The laser was activated and thermometry images were obtained. Two trajectories, posteromedial and anterolateral, produced satisfactory tumor ablation. Conclusion LITT with intraoperative MRI and stereotactic image guidance is a newly available, minimally invasive, and therapeutically viable technique for the treatment of deep seated brain tumors.
Review of the results from clinical studies on the efficacy, safety and tolerability of mirtazapine for the treatment of patients with major depression

Mirtazapine is a presynaptic alpha-2 antagonist that has dual action by increasing noradrenergic and serotonergic neurotransmission. The enhancement of serotonergic neurotransmission is specifically mediated via 5-HT1 receptors because mirtazapine is a postsynaptic serotonergic 5-HT2 and 5-HT3 antagonist. In addition, mirtazapine has only a weak affinity for 5-HT1 receptors and has very weak muscarinic anticholinergic and histamine (H1) antagonist properties. As a consequence of its unique pharmacodynamic properties, mirtazapine is an effective, safe and well-tolerated addition to the antidepressant armamentarium. Mirtazapine is well absorbed from the gastrointestinal tract following oral administration, and it is extensively metabolized in the liver to four metabolites via demethylation and hydroxylation, followed by glucuronide conjugation. The unconjugated desmethyl metabolite is pharmacologically less active than the parent compound. Mirtazapine lacks auto-induction of hepatic isoenzymes. Although mirtazapine is a substrate of P450 isoenzymes 1A2, 2D6 and 3A4, in vitro studies show that it is not a potent inhibitor or inducer of any of these enzymes. Mirtazapine has been evaluated in a worldwide clinical development program involving approximately 4500 patients. Controlled clinical trials involving almost 2800 mirtazapine-treated patients have demonstrated the compound to be effective for the treatment of moderate-to-serve major depression. Mirtazapine was consistently superior to placebo, and equivalent in efficacy to the tricyclic antidepressants amitriptyline, doxepin and clomipramine, but with an improved tolerability profile. Mirtazapine has shown a rapid onset of action in patients with predominantly severe depressive illness in a comparative study against fluoxetine. Mirtazapine has a unique tolerability profile, since the specific postsynaptic 5-HT2 and 5-HT3 receptor blockade of mirtazapine provides early antidepressant effects without causing unwanted serotonin-related side-effects. Transient somnolence, hyperphagia and weight gain are the most commonly reported adverse events, which may be attributed to the antihistaminic (H1) activity of mirtazapine at low doses. Somnolence, the most commonly reported side-effect, appears to be less frequent at higher dosages. Mirtazapine also demonstrates important anxiolytic and sleep-improving effects, which may be related to its pharmacodynamic properties. In addition, mirtazapine does not appear to be associated with sexual dysfunction. Mirtazapine has shown no significant cardiovascular adverse effects at multiples of 7 to 22 times the maximum recommended dose. Mirtazapine is a unique addition to the antidepressant armamentarium as first-line therapy in patients with major depression and symptoms of anxiety/agitation or anxiety/somatization or complaints of insomnia and as a useful alternative in depressed patients who do not adequately respond to or are intolerant of tricyclic antidepressants or serotonin-specific reuptake inhibitors.
Primary Prophylaxis of Variceal Bleeding

Morphologic changes in the liver increase resistance to portal blood flow in patients with chronic liver disease. In addition to the fixed defect caused by cirrhosis, the reversible contractile component induced by decreased synthesis of NO in the hepatic vascular bed and the hyperdynamic splanchnic circulation, induced by the local and systemic neurohumoral mechanisms, aggravate the portal hypertension and the development of gastroesophageal varices.1 The presence of gastroesophageal varices is not universal among patients with cirrhosis. In cross-sectional studies, gastroesophageal varices were seen in only a third of patients with cirrhosis. A longitudinal surveillance study found that only 31% of patients (83/265) with primary biliary cirrhosis developed varices during a median follow-up of 5.6 years.2 In this study, serum bilirubin and histopathologic staging were independent predictors for the development of varices, and, among patients who developed varices, 1-year and 3-year bleeding rates were, respectively, 33% and 41%. Current evidence suggests that a third of patients with documented esophageal varices bleed within 2 years from the time of diagnosis. Bleeding from varices is an unpredictable complication of cirrhosis that has an associated mortality of 20% to 40% with each episode.3-6 In a recent study, it was demonstrated that the in-hospital mortality rate for acute variceal bleeding has remained around 20% during the past decade despite advances in the management of acute variceal bleeding.7 Many patients who survive the immediate post-bleeding period subsequently die from the complications of bleeding, including sepsis, bacterial peritonitis, and renal failure. The mortality associated with variceal bleeding is related directly to the severity of liver disease with a relatively low mortality for patients with Child A cirrhosis (∼10%-20%) and an extremely high mortality (∼70%) for those with Child C cirrhosis.3-6 Only a third of all deaths in patients with cirrhosis are directly attributed to variceal bleeding, an important consideration when the results of clinical trials are analyzed. Unfortunately, many interventional studies have lacked adequate sample size to show a difference in overall mortality or bleedingrelated mortality. The rationale for primary prophylaxis (prevention of first bleeding episode) is based on the extremely high mortality associated with each bleeding episode. The aim of primary prophylaxis is to treat high-risk patients with minimal complications. The treatment should be relatively inexpensive, effective, and should reduce bleeding-associated mortality and improve overall survival. In this review, the risk factors are discussed for first variceal bleeding, the optimal treatment, and the efficacy and cost-effectiveness of primary prophylaxis.
Use of a Removable Endobronchial Valve for the Treatment of Bronchopleural Fistula

We report the case of a patient with a prolonged bronchopleural fistula and empyema that were successfully treated by the placement of a removable, unidirectional endobronchial valve. This is the first report of the use of such a device for this indication.
Elemental prospecting and geoarchaeology in Turkey and Mexico

Abstract Understanding past human impacts on soils requires many forms of evidence including elemental chemistry. Human activities leave traces of different elements, distinguishing activity sites. Since the 1990s more scholars have used a full range of analytical techniques including inductively coupled plasma-atomic emission spectroscopy (ICP/AES), and inductively coupled plasma-mass spectroscopy (ICP/MS). Also since that time the near singular focus on phosphate as a prime indicator of human activity has broadened to include a large suite of elemental indicators, aided by the emergence of many tools and techniques such as ICP. This paper focuses on the elemental chemistry of sediments at two archaeology sites, Chunchucmil, Mexico, and Kinet, Turkey. The purpose of this study is to understand how certain elements correlate with each other and vary by space and time at different archaeology sites, and as an important methodological consideration, how different solvents affect ICP-AES analyses. In other words, does human activity significantly alter the elemental chemistry of a site, and if so, is this in a systematic way or does it vary geographically? And, are these chemical signatures of human activity hidden or highlighted by different ICP methods? We examined soil chemistry by types of geomorphic and archaeological location contexts (e.g., floors, natural deposits, walls, streets) and by age of deposit (e.g., Hellenistic, Iron Age) to detect differences in soil chemistry signatures associated with them, and for regional variations in ICP methods’ effectiveness. Our analyses revealed detectable differences between natural and anthropogenic deposits, site types, eras, and large differences between methods. High amounts of lead were correlated with streets and rooms in the Medieval and Bronze periods in Kinet, Turkey and natural deposits had lower levels of cadmium and mercury. ICP-NP treatments revealed higher detection levels of most elements than did ICP-DT treatments in Chunchucmil, Mexico.
Physiological basis for preferential uptake of d-α-aminoadipate over the l-isomer by Alcaligenes denitrificans

Abstract Alcaligenes denitrificans , pre-incubated with d -α-aminoadipate and assayed for l -isomer uptake without removal of extracellular d -isomer, exhibits a reduced rate of uptake and a reduced level at which steady state is achieved. During d - or l -isomer uptake, intracellular α-aminoadipate is exclusively the l -configuration. These data are consistent with an intracellular, mediated reduction in l -isomer uptake as the physiological basis for preferential d -α-aminoadipate uptake by A. denitrificans growing on racemic α-aminoadipate. Translocated d -α-aminoadipate is rapidly metabolized to form an l -isomer pool which subsequently reduces the rate of l -isomer uptake and the level at which steady state occurs resulting in a preferred d -isomer uptake. Competitive inhibition of l -α-aminoadipate uptake by the d -isomer or a difference in the maximum rates of uptake of each isomer does not contribute to preferential uptake. d -α-aminoadipate uptake is an inducible process expressed only in the presence of that compound and while uptake of l -α-aminoadipate is also inducible there is a low rate of constitutive uptake. While l -α-aminoadipate uptake occurs against a concentration gradient, uptake of the d -isomer is not against a gradient. d - and l -isomer uptake are active processes since both are inhibited by azide, cyanide and 2,4-dinitrophenol.
Interview Duration, Interpersonal Attraction, and Hiring Decisions:

Length of the interview, applicants' behavior, and interview strategy were manipulated to investigate their interactive effects on ratings and hiring decisions. 202 students viewed either a short o...
Flat plate streaming potential investigations: Hydrodynamics and electrokinetic equivalency

Abstract The accurate measurement of streaming potentials in either capillaries or flat plate systems requires Poiseuille flow, i.e., flow must be steady, incompressible, laminar, and established. The established flow stipulation is rarely addressed yet it is of critical importance. Our findings suggest that while the onset of turbulence causes no abrupt change in the streaming potential, flow must be established throughout at least 90% of the flow field for accurate streaming potential measurement. The development of a flat plate flow system based on (1 × 25 × 75) mm plates is discussed in light of the hydrodynamic requirements. The electrokinetic equivalency between plates and capillaries of the same material is discussed and the small discrepancy is attributed to surface roughness and possible differences in surface chemical composition. The flat plate system offers substantial advantages over capillaries in that both surface treatments and analyses via a variety of quantitative techniques are greatly facilitated.
Characterization of the Capsid Protein Glycosylation of Adeno-Associated Virus Type 2 by High-Resolution Mass Spectrometry

Adeno-associated virus type 2 (AAV-2) capsid proteins have eight sequence motifs that are potential sites for O- or N-linked glycosylation. Three are in prominent surface locations, close to the sites of cellular receptor attachment and to neutralizing epitopes on or near protrusions surrounding the three-fold axes, raising the possibility that AAV-2 might use glycosylation as a means of immune escape or for preventing reattachment on release of progeny virus. Peptide mapping and structural analysis by Fourier transform ion cyclotron resonance mass spectrometry demonstrates, however, no glycosylation of the capsid protein for virus prepared in cultured HeLa cells.
On some quartz-plagioclase veins in the Connemara schists, Ireland

Quartz-plagioclase veins in staurolite schists often have margins depleted in the vein minerals. In some cases vein formation has simply involved recrystallization of groundmass grains into large vein grains in a closed system. The driving force for this process is reduction of strain energy and surface free energy. It is suggested that the veins initiate when grain boundaries have been opened up by hydraulic fracturing during medium grade metamorphism. The segregation process can be explained by a model of local equilibrium between grains and a continuous pore fluid similar to that commonly applied to metasomatic reactions; however, no phase change occurs.
The Groshong Catheter as an Intraperitoneal Access Device in the Treatment of Ovarian Cancer Patients

With the development of new intraperitoneal treatments in ovarian cancer, safe and convenient access to the peritoneal cavity is now required. This report reviews the University of Alabama at Birmingham's experience with the Groshong catheter as an intraperitoneal access device. The Groshong was easily inserted intraperitoneally in 20 ovarian cancer patients and used to deliver 81 courses of intraperitoneal therapy over 2310 patient-days. There were no catheter-related complications during treatment and only one exit site infection after catheter removal. Further investigation of the Groshong catheter as a novel intraperitoneal access device appears warranted.
Linear and Circular Dichroism in Angle Resolved Fe 3 p Photoemission

Using a recently developed spin-polarized, fully relativistic, multiple scattering approach based on the layer KKR Green function method, we have reproduced the Fe 3p angle-resolved soft x-ray photoemission spectra and analyzed the associated large magnetic dichroism effects for excitation with both linearly and circularly polarized light. Comparison between theory and experiment yields a spin-orbit splitting of 1.0 – 1.2 eV and an exchange splitting of 0.9 – 1.0 eV for Fe 3p. These values are 50 – 100 % larger than those hitherto obtained experimentally.