cssi/SciSciGPT-SciSciNet huggingface dataset:
Biotyping coagulase-negative staphylococci.

The biochemical profiles obtained with Staph-Ident (Analytab Products, Plainview, N.Y.) panels were combined with the results of adherence and synergistic hemolysis tests to define biotypes among 1,064 clinical isolates representing eight species of coagulase-negative staphylococci. The 672 isolates of Staphylococcus epidermidis were aligned in 69 of 144 potential biotypes in our scheme because of 18 different biochemical profiles and the eight physiologic subtypes. Isolates of most other species were in fewer biotypes because of more uniform adherence and synergistic hemolysis data, as well as fewer biochemical profiles. Since adherence and synergistic hemolysis may prove to be related to virulence and pathogenicity, biotyping with these test results would help evaluate the reliability of adherence and synergistic hemolysis as possible indices of the clinical significance of some of these organisms. When the antimicrobial susceptibility and plasmid profiles obtained on two clusters of S. epidermidis isolates were compared with the biotyping results, one cluster was not further differentiated by plasmid profiles, but was by antimicrobial profiles; the other cluster with only two biotypes was further divided into five distinct types by plasmid profiles but was not separated at all by antimicrobial profiles. Images
World Society and the University as Formal Organization

This paper describes and interprets the worldwide transformation of universities with respect to how they account for excellence. It first reflects on the rationalized university as an organizational ideal and the implications of rationalization on standardizing university practices. The paper then focuses on two interrelated phenomena: the assessment of faculty and the assessment of universities, as illustrations of accounting-for-excellence. Examining the annual faculty report and tenure protocol as examples of common organizational practices within American universities, it argues that these practices facilitate American university participation in national and international university rankings. Finally, it is argued that American universities underwent earlier organizational rationalization and differentiation than universities in other countries in part because they were less differentiated from other social institutions. In the absence of the buffering authority of the state and the professoriate, American universities early on became organizational actors dealing with multiple stakeholders in search of resources and legitimacy.
Decoding general relativity

For a field of physics which is relatively new, which was tiny for almost half of its history to date, and not especially large even today, general relativity has attracted a fair measure of interest from historians of science. Even so, the sheer enormity of the task facing historians of science in general is illustrated by the fact that the surface has barely been scratched in many of the most intriguing parts of the history of this subject. Most attention to date has focused on the genesis of the theory, surely one of the remarkable stories in all of science, but relatively little on the later history, apart from some studies of the recent development of the field of gravitational waves and their detection. The pioneer of the middle history of this subject, Jean Eisenstaedt, has left us with a picture of the ‘‘low water mark’’ of relativity from 1925 to 1955 and a fascinating account of how relativists grappled with (and frequently missed) the meaning of the Schwarzschild solution describing the gravitational field of a point mass, what we would now call a black hole. Fulvio Melia’s book Cracking the Einstein Code: Relativity and the Birth of Black Hole Physics takes up the story where Eisenstaedt’s account leaves off and describes how the groundwork was laid for the golden age of black hole physics from 1965 to 1975. This, I know from my own research, is a fascinating story, and Melia tells it very engagingly in a way which makes it accessible to the widest possible audience. Melia, himself a well-known astrophysicist, does a remarkable job of covering an immense amount of ground in the history of a technical field in a concise, readable book. The book resolves itself into several sections, the first being a breezy resume of the history of relativity up to the mid-twentieth century. Then comes a captivating chapter in which Melia, using one of the earliest physics conferences devoted to general relativity, the 1962 Warsaw conference, as his focal point, gives an excellent history of the emergence of some of the key ideas which would lead to the
Hubble Space Telescope on-orbit NiH/sub 2/ battery capacity performance (1990 to 2002)

This work summarizes the Hubble Space Telescope nickel-hydrogen (NiH/sub 2/) battery capacity performance from launch to the present time. Over the life of HST vehicle configuration, equipment degradation and equipment failures have had a significant effect on the capacity of the HST batteries. Changes made to the charge system configuration in order to protect against equipment failures and to maintain battery thermal stability resulted in undercharging of the batteries. This undercharging resulted in decreased usable battery capacity as well as battery cell voltage/capacity divergence. This cell divergence was made evident during battery onorbit health checks by a more shallow slope of the discharge curve following the discharge knee. Early efforts to improve the battery performance have been successful. Onorbit health check data indicates increases in the usable battery capacity of all six batteries as well as improvements in the battery cell voltage/capacity divergence. Additional measures have been implemented to improve battery performance, however, failures within the HST Power Control Unit (PCU) has prevented verification of battery health. As this PCU fault prevents the execution of on-orbit capacity testing, the HST Project has based the battery capacity on trends, which utilizes previous onorbit battery capacity test data, for science mission and servicing mission planning. The servicing mission 3B, scheduled for February 2002, will replace the faulty PCU. Following the servicing mission, on-orbit capacity testing will resume.
Surgical management of middle cerebral artery aneurysms: experience with transsylvian and superior temporal gyrus approaches.

Abstract BACKGROUND Middle cerebral artery (MCA) aneurysms are typically approached surgically using one of three basic techniques. The sylvian fissure can be opened in one of two ways; either from medial to lateral or from lateral to medial. Alternatively, an incision in the superior temporal gyrus with subpial resection can be used to expose the MCA branches and aneurysm neck. METHODS We reviewed 65 middle cerebral aneurysms in 62 patients operated on over a 5-year interval where a choice of operative approach was made based on preoperative evaluation of available radiological studies. RESULTS The superior temporal gyrus was used when intraparenchymal hematoma was present in the temporal lobe or when the length of the middle cerebral artery trunk was long (average length 2.44 ± 0.41 SE cm). This approach was used in 20 operations on 22 aneurysms. The sylvian fissure approach was used in cases where the middle cerebral artery main trunk was short (1.32 ± 0.41 SE cm) or the direction of the aneurysm was favorable. This approach was used in 38 operations. In 4 operations (5 aneurysms) we combined the two approaches to remove clot, obtain adequate exposure, and secure control of the proximal MCA. CONCLUSIONS In most cases of MCA aneurysms the decision as to which surgical approach to use is made preoperatively depending on the presence of intraparenchymal clot, size of aneurysm, direction of aneurysm, and length of the proximal middle cerebral artery.
NMR powder spectrum simulation for nuclei withI > 1/2

A program to calculate powder NMR spectra for nuclei with spin I > 1/2 is written. The spin Hamiltonian used includes Zeeman term, isotropic dipolar broadening, anisotropic chemical shift, and quadrupolar interaction with asymmetric field gradient treated up to second-order term of perturbation theory. Two sites with different sets of parameters determining the shape of the spectrum can be included in calculation. The approach to the problem is entirely numerical without deriving analytical formulas for the lineshape. Ein Programm zur Berechnung von NMR-Spektren polykristalliner Pulver fur Kerne mit Spin I > 1/2 wird geschrieben. Der dazu verwendete Spin-Hamilton-Operator schliest folgende Parameter ein: Zeeman-Term, dipolare isotrope Bandverbreiterung, anisotrope chemische Verschiebung und quadrupolare Wechselwirkung mit asymmetrischen Feldgradienten, errechnet mit einer Naherung zweiter Ordnung der Storungstheorie. Zwei Atom-Positionen mit verschiedenen Parametersatzen, welche die Form des Spektrums bestimmen, konnen in die Berechnung einbezogen werden. Die Problemlosung erfolgt ausschlieslich numerisch unter Vermeidung von analytischen Gleichungen fur die Linienform.
Synthesis and characterization of unsupported ferric oxide ceramic membranes

Abstract Unsupported ferric oxide ceramic membranes have been synthesized by the sol-gel method using two different formulations. These materials have been characterized by N 2 -sorption, electron microscopy and FTIR spectroscopy. In one formulation, mesoporous membranes with a mean pore radius of 5 nm were fabricated from asymmetric goethite (α-FeOOH) by control of the particles surface charge during drying. This material also developed slit-shaped intraparticle micropores during thermal dehydration to hematite (α-Fe 2 O 3 ), resulting in a considerable increase in active surface area without affecting membrane microstructure or mesoporosity. These membranes may be suitable as an intermediate support layer in a multilayer catalytic ceramic membrane configuration. In a second formulation, highly uniform microporous unsupported membranes with a pore radius less than 1.7 nm were prepared from the hydrolytic iron oxide polymer [Fe(O,OH,H 2 O) 6 ] n . It was found that the initial hydrolysis reaction conditions determine the microstructure of the formed membranes. The effects of hydrolysis conditions and post-hydrolysis treatment on polymer formation and membrane microstructure is discussed.
Narrative references to older African Americans living under slavery

Abstract A review of 2,200 ex-slave narratives collected in the 1930s and other historic sources was conducted to find references to how older African Americans lived during the time of slavery. These sources reveal that older African American slaves were less valued by White society as they aged, but within the African American community played productive roles, were cared for, and respected.
Response to “Lessons from the Sandbox: Is Unexplained Nitrogen Real?”

The scientific literature is full of papers that are thick with numbers and details but thin on novelty. The Hubbard Brook sandbox experiment was a novel idea that clearly warrants replication in the future. The watershed-scale ecosystems of the Hubbard Brook Experimental Forest are too variable to estimate changes in nitrogen (N) content with much precision, so Bormann and others (1993) set out to control initial “ecosystem” N content and variation by creating new mesoscale ecosystems in “sandboxes.” They found an apparent accumulation of N that could not be explained by conventional views of forest biogeochemistry. Our review of reported rates of change in the N content of forests (Binkley and other 2000) concluded that the evidence for high rates of N accretion in these sandbox ecosystems was weak. Bormann and others (2002) responded with a more detailed evaluation of the N budget of the Hubbard Brook sandbox ecosystems, sharing their data with reviewers to allow a careful cross-checking of the budgets. This open and careful reexamination of a controversial experiment is a great example of how science ought to work. The revised sandbox N budgets have an unex
Superconducting phase diagram of UPt3 for fields along a nonsymmetric orientation from ultrasonic measurements.

A [ital H]-[ital T] superconducting phase diagram is presented for UPt[sub 3] which is obtained from ultrasonic velocity meausrements with the field at 45[degree] to the [ital c] axis. The implications of the phase diagram on various theoretical models are discussed.
Reliability of quantitative motor unit action potential parameters.

We evaluated the test–retest reliability (reproducibility) of motor unit action potential (MUAP) parameters in multi-MUAP analysis over time. Reproducibility studies are not available for needle quantitative electromyography (QEMG) performed by the same examiner. Fourteen consecutive individuals (10 men and 4 women) had repeat QEMG at 3 hours after the first examination, and seven (5 men and 2 women) had a repeat QEMG after 4–10 days. The intraclass correlation coefficient (ICC) was 87–97% with same-day testing and 52–81% with different-day testing. Size index and firing rate were the most reproducible, suggesting use in follow-up multi-MUAP studies. Muscle Nerve 30: 111–113, 2004
Oxidative stress, lipid rafts, and macrophage reprogramming

Oxidant stress, induced under a variety of conditions, is known to lead to the molecular reprogramming of the tissue-fixed macrophage. This reprogramming is associated with an altered response to subsequent inflammatory stimuli, such as lipopolysaccharide (LPS), leading to enhanced liberation of proinflammatory chemokines and cytokines. Due to this altered response, dysregulated immunity ensues, leading to the development of clinical syndromes such as multiple organ dysfunction syndrome (MODS). Although the mechanisms responsible for this altered macrophage activity by oxidant stress remains complex and poorly elucidated, it appears, based on recent research, that early and direct alterations within lipid rafts are responsible. This early and direct interaction with lipid rafts by oxidants leads to the mobilization of annexin VI from lipid raft constructs, leading to the release of calcium. This increased cytosolic concentration of this secondary messenger, in turn, results in the activation of calcium-de...
Vertical confinement and interface effects on the microstructure and charge transport of P3HT thin films

ABSTRACT: Using X-ray diffraction-based pole figures, we pres-ent quantitative analysis of the microstructure of poly(3-hex-ylthiophene) thin films of varying thicknesses, which allows usto determine the crystallinity and microstructure at the semi-conductor-dielectric interface. We find that the interface isapproximately one fourth as crystalline as the bulk of the mate-rial. Furthermore, the use of a self-assembled monolayer(SAM) enhances the density of interface-nucleated crystallitesby a factor of 20. Charge transport measurements as a func-tion of film thickness correlate with interface crystallinity.Hence, we establish the crucial role of SAMs as nucleatingagents for increasing carrier mobility in field-effect devices. V C 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys000: 000–000, 2013 KEYWORDS: charge transport; crystallization; structure-propertyrelations; thin films; X-rayINTRODUCTION Organic semiconductors, comprising smallmolecules and conjugated polymers, are a promising materi-als family for next generation electronic devices such as tran-sistors, light-emitting diodes and solar cells. Processes atinterfaces play a very important role in the operation ofthese devices. Because in organic semiconductors the micro-structure is intimately tied to their electronic properties,understanding the effect of surfaces and interfaces on themorphology of these materials is an important component ofoptimizing their performance. In thin film transistors (TFTs)for instance, mobile charge is transported within a few nano-meters of the semiconductor/dielectric interface, which inthe case of bottom-gated devices is the substrate surface.There is significant experimental evidence demonstratingthat controlling the molecular packing and orientation at thedielectric interface can improve the charge carrier mobilityin thin films of poly(3-hexylthiophene) (P3HT), a modelsemicrystalline, semiconducting polymer, by several ordersof magnitude.
Genetic interactions between SIN3 mutations and the Saccharomyces cerevisiae transcriptional activators encoded by MCM1, STE12, and SWI1

SIN3 was first identified by a mutation which suppresses the effects of an swi5 mutation on expression of the HO gene in Saccharomyces cerevisiae. We now show that a sin3 mutation also partially suppresses the effects of swi1 on HO transcription, and partially suppresses the growth defect and inositol requirement observed in swi1 mutants. This suggests that SIN3 and SWI1 may play opposite regulatory roles in controlling expression of many yeast genes. Yeast SIN3 has been shown to function as a negative transcriptional regulator of a number of yeast genes. However, expression of the yeast STE6 gene is reduced in a sin3 mutant strain. This suggests that SIN3 functions as a positive regulator for STE6 transcription, although this apparent activation function could be indirect. In order to understand how SIN3 functions in STE6 regulation, we have performed a genetic analysis. It has been previously demonstrated that MCM1 and STE12 are transcriptional activators of a-specific genes such as STE6, and we now show that SWI1 is also required for STE6 expression. Our data suggest that STE12 and SWI1 function in different pathways of activation, and that STE12 is epistatic to SIN3 and SWI1. We show that the activities of the Mcm1p and Ste12p activators are modestly reduced in a sin3 mutant strain, and that phosphorylation of the Ste12p activator is decreased in a sin3 mutant. Thus, it is possible that the decreased transcription of STE6 in sin3 mutants is due to the combined effect of the diminished activities of Mcm1p and Ste12p.
Learning sound/symbol correspondences: Transfer effects of pattern detection and phonics instruction

This study tested predictions derived from Gibson and Levin (1975) and Gough and Hillinger (1980) regarding the effects of different forms of reading instruction on a test of ‘far generalization’, where students were asked read nonsense words containing untaught sound/symbol correspondences. Two instructional methods were compared, pattern detection training and a synthetic phonics lesson which taught the specific correspondences used on a first post-test. A control group received no treatment. The transfer effects of pattern detection training were demonstrated on a first post-test and with a measure of correspondence induction at the end of testing. A first and second post-test revealed that specific correspondence training increased decoding scores but did not transfer to novel correspondences. On a second post-test, pattern detection and specific correspondence groups did not differ in decoding score; apparently the induction skill of the pattern detection group was balanced by the knowledge base of the specific correspondence group. It is concluded that pattern detection training more readily fosters those abilities that allow students to independently induce sound/symbol correspondences than the traditional approach of direct teaching of specific correspondences.
Second order necessary and sufficient conditions for convex composite NDO

In convex composite NDO one studies the problem of minimizing functions of the formF:=h ○f whereh:ℝ m → ℝ is a finite valued convex function andf:ℝ n → ℝ m is continuously differentiable. This problem model has a wide range of application in mathematical programming since many important problem classes can be cast within its framework, e.g. convex inclusions, minimax problems, and penalty methods for constrained optimization. In the present work we extend the second order theory developed by A.D. Ioffe in [11, 12, 13] for the case in whichh is sublinear, to arbitrary finite valued convex functionsh. Moreover, a discussion of the second order regularity conditions is given that illuminates their essentially geometric nature.
Third harmonic generation and destructive interference with femtosecond laser pulses

With an unfocused femtosecond laser tuned to overlap three-photon resonance with a fine structure doublet, a third harmonic field is predicted which has a bandwidth much narrower than that of the laser. Consequently, this third harmonic field decays slowly with time, lasting as long as several nanoseconds. The population left in the excited states is suppressed by a destructive interference between different excitation pathways.
Tunnel Diodes Fabricated For Rectenna Applications Using Self-Assembled Nanodielectrics

Abstract Fabrication of the organic tunnel diode was carried out by first preparing a low roughness Au film on an oxidized Si substrate. Photo resist masked application of alkanethiol film was carried out in ethanol to form a stable, highly ordered film by sulfur-gold bonding. Analysis of the film was performed using impedance spectroscopy and atomic force microscopy (AFM). Subsequent surface micromachining applied the complementary metal layer to the tail end of the film forming a permanent tunnel junction. The film thickness was experimentally verified to be 1.5 nm and in agreement with the chemical model. Testing of the tunnel junction was performed at room temperature on a probe station where the current-voltage characteristics showed a highly symmetrical diodic response.
Issue Costs in Fisher's Two-Period Model

This paper analyzes the impact of issue costs on firm investment and dividend policies within the context of the two-period Fisher model. Consistent with its pedagogical tone, the paper illustrates graphically the loss in value stemming from a high dividend payout by a firm subject to issue costs in its external financing. Two components compose the overall loss in value. The “substitution effect” results from a shift in the investment opportunity set, while the “wealth effect” stems from the loss in value owing to issue costs. The paper suggests that the firm, when increasing its dividend payout, must weigh the marginal loss in firm value against the offsetting benefits, which may take the form of reduced monitoring costs.
Mesenchymal stem cell secretome and regenerative therapy after cancer

Cancer treatment generally relies on tumor ablative techniques that can lead to major functional or disfiguring defects. These post-therapy impairments require the development of safe regenerative therapy strategies during cancer remission. Many current tissue repair approaches exploit paracrine (immunomodulatory, pro-angiogenic, anti-apoptotic and pro-survival effects) or restoring (functional or structural tissue repair) properties of mesenchymal stem/stromal cells (MSC). Yet, a major concern in the application of regenerative therapies during cancer remission remains the possible triggering of cancer recurrence. Tumor relapse implies the persistence of rare subsets of tumor-initiating cancer cells which can escape anti-cancer therapies and lie dormant in specific niches awaiting reactivation via unknown stimuli. Many of the components required for successful regenerative therapy (revascularization, immunosuppression, cellular homing, tissue growth promotion) are also critical for tumor progression and metastasis. While bi-directional crosstalk between tumorigenic cells (especially aggressive cancer cell lines) and MSC (including tumor stroma-resident populations) has been demonstrated in a variety of cancers, the effects of local or systemic MSC delivery for regenerative purposes on persisting cancer cells during remission remain controversial. Both pro- and anti-tumorigenic effects of MSC have been reported in the literature. Our own data using breast cancer clinical isolates have suggested that dormant-like tumor-initiating cells do not respond to MSC signals, unlike actively dividing cancer cells which benefited from the presence of supportive MSC. The secretome of MSC isolated from various tissues may partially diverge, but it includes a core of cytokines (i.e. CCL2, CCL5, IL-6, TGFβ, VEGF), which have been implicated in tumor growth and/or metastasis. This article reviews published models for studying interactions between MSC and cancer cells with a focus on the impact of MSC secretome on cancer cell activity, and discusses the implications for regenerative therapy after cancer.
Vascular endothelial growth factor inhibits mitogen-induced vascular smooth muscle cell proliferation.

Abstract Introduction Delivery of vascular endothelial growth factor (VEGF) protein or gene transfer has been shown to accelerate re-endothelialization and attenuate neointimal hyperplasia in various arterial injury models, including balloon injury, stent implantation, and vein grafts. In addition to stimulating re-endothelialization, we hypothesize that VEGF has further vascular protective functions to prevent neointimal hyperplasia by directly inhibiting mitogen-induced proliferation of vascular smooth muscle cells (VSMCs) via the mitogen-activated protein kinase pathway. Materials and methods Human aortic VSMCs were seeded and serum starved for 24 h. The cells were then stimulated with a mitogen, recombinant human platelet derived growth factor at 20 ng/mL together with 0, 10, 20, 30, 40, 50 ng/mL recombinant human VEGF. A proliferation assay was used to quantitate bromodeoxyuridine uptake into newly synthesized DNA. Western immunoassay was used to quantify extracellular signal-regulated kinase (ERK) 2 protein and phosphorylation of retinoblastoma and ERK 1/2 protein. Results VEGF inhibited bromodeoxyuridine incorporation into mitogen-induced VSMC in a dose-dependent manner, reaching statistical significance at concentrations of 30 ( P P P Conclusion In addition to stimulating re-endothelialization, VEGF appears to have a vascular protective function by directly inhibiting VSMC proliferation. This effect occurs in the absence of endothelial cells and via the mitogen-activated protein kinase pathway. VEGF may serve as an important modulator of mitogen-induced VSMC proliferation after vascular injury.
Histopathologic biomarkers in feral freshwater fish populations exposed to different types of contaminant stress

Histopathologic alterations of gill, liver, and spleen were studied in feral fish from three freshwater ecosystems that experience different types of contaminant stress. East Fork Poplar Creek (EFPC), a third-order stream in East Tennessee, receives point source discharges of mixed contaminants from a nuclear weapons facility located near its headwater. The Pigeon River (PR), a high-gradient fifth order stream, is impacted by bleached kraft mill effluent (BKME). Hartwell Reservoir (HR), a US Army Corp of Engineers impoundment of the Savannah River, contains high levels of PCBs in sediment and biota. Brushy Fork Creek (BFC), the Little River (LR), and the Tugaloo River (TR) are relatively free of contaminants, and served as reference sites for the three respective ecosystems of this study. Certain organ and tissue lesions, detected microscopically, were common to fish from both reference and contaminated sites. These included parasites, inflammation, glycogen deficiency, macrophage aggregates (MA), and diffuse fatty change in the liver; parasites and MA in the spleen; and parasites, secondary lamellar fusion, and variable epithelial cell hyperplasia in the gills. Lesions found only in fish from contaminated sites were: (1) cholangiomas in liver of redbreast sunfish (Lepomis auratus) collected from EFPC; (2) amphophilic and eosinophilic foci of cellular alteration, diffuse biliary preductular and ductular hyperplasia with islands of hyperplastic basophilic hepatocytes, and two metastatic thyroidal carcinomas in spleen of redbreast sunfish from PR; (3) severe lipidosis, vacuolated and basophilic foci in largemouth bass (Micropterus salmoides) from HR; (4) splenic lymphoid cell depletion and vascular congestion, with necrosis of reticuloendothelial cells in fish collected from EFPC and HR; (5) hyperplasia of mucous and chloride cells, deformed branchial cartilage, severe and diffuse aneurysms of lamellae, and edema at the base of the secondary lamellae were in gill of fish from all three sites. The finding of specific lesions only in fish from contaminated sites suggests a contaminant etiology. Histopathology biomarker lesions identified in this study are similar to those observed in laboratory exposures of fishes to specific pollutants. Further refinement of these biomarker approaches will be discussed in light of multiple stressors and their effects.
Brain stimulation using electromagnetic sources: theoretical aspects

We prove that, at the frequencies generally proposed for extracranial stimulation of the brain, it is not possible, using any superposition of external current sources, to produce a three-dimensional local maximum of the electric field strength inside the brain. The maximum always occurs on a boundary where the conductivity jumps in value. Nevertheless, it may be possible to achieve greater two-dimensional focusing and shaping of the electric field than is currently available. Towards this goal we have used the reciprocity theorem to present a uniform treatment of the electric field inside a conducting medium produced by a variety of sources: an external magnetic dipole (current loop), an external electric dipole (linear antenna), and surface and depth electrodes. This formulation makes use of the lead fields from magneto- and electroencephalography. For the special case of a system with spherically symmetric conductivity, we derive a simple analytic formula for the electric field due to an external magnetic dipole. This formula is independent of the conductivity profile and therefore embraces spherical models with any number of shells. This explains the "insensitivity" to the skull's conductivity that has been described in numerical studies. We also present analytic formulas for the electric field due to an electric dipole, and also surface and depth electrodes, for the case of a sphere of constant conductivity.
Extrarenal potassium tolerance in chronic renal failure: implications for the treatment of acute hyperkalemia.

The role of extrarenal potassium homeostasis is well recognized as a major mechanism for the acute defense against the development of hyperkalemia. The purpose of this report is to examine whether or not the various mechanisms of extrarenal potassium regulation are intact in patients with end-stage renal disease (ESRD). The available data suggest that with the development of ESRD and the uremic syndrome there is impaired extrarenal potassium metabolism that is related to a defect in the Na,K-adenosine triphosphatase (ATPase). The responsiveness of uremic patients to the various effector systems that regulate extrarenal potassium handling is discussed. Insulin is well positioned to play an important role in the regulation of plasma potassium concentration in patients with impaired renal function. The role of basal insulin may be even more important than previously appreciated, since somatostatin infusion causes a much greater increase in the fasting plasma potassium in rats with renal failure than in controls. Furthermore, stimulation of endogenous insulin by oral glucose results in a greater intracellular translocation of potassium in uremic rats than in controls. Under at least two common physiologic circumstances, feeding and vigorous exercise, endogenous catecholamines might also act to defend against acute increments in extracellular potassium concentration. However, it is important to appreciate that the response to β2-adrenoreceptor-mediated internal potassium disposal is heterogeneous as judged by the variable responses to epinephrine infusion. Based on the evidence presented in this report, a regimen for the treatment of life-threatening hyperkalemia is outlined. Interpretation of the available data demonstrate that bicarbonate should not be relied on as the sole initial treatment for severe hyperkalemia, since the magnitude of the effect of bicarbonate on potassium is variable and may be delayed. The initial treatment for lifethreatening hyperkalemia should always include insulin plus glucose, as the hypokalemic response to insulin is both prompt and predictable. Combined treatment with β2-agonists and insulin is also effective and may help prevent insulininduced hypoglycemia.
Some examples of historical cryptanalysis

Abstract The term “historical cryptanalysis” is introduced and defined as the solving of cryptograms whose keys have been lost or misplaced. Numerous examples of such cryptograms, many undeciphered since their deposit in archives hundreds of years ago, still exist and may contain important historical and literary information. Credit is given to previous investigators in this field, who often performed individual cryptanalytic feats of great brilliance. A new approach of international coordinated research in historical cryptanalysis--bringing together the scholars who discover cryptographic materials and those who can help with their cryptanalysis--is discussed. A few examples of solved cryptograms are presented to demonstrate some of the methods used to encipher and cryptanalyze information. Included are a Papal cipher containing information about the election of the king of Poland in 1573, a German cryptogram written by a participant in a key event of the Counter-Reformation--the choice of the archbishop of Cologne in 1583, a Venetian cipher from 1630 whose key may have been eaten to preserve the cipher's security, a Russian cryptanalyst's worksheet from the time of Catherine the Great, and a military cipher from the American Civil War.
Age-Dependent Disposition of Amobarbital: Analog Computer Evaluation

: Previously published observations on 4-hour and 24-hour amobarbital blood levels in two groups of subjects (ages 20-40 and over-65) were analyzed with use of an analog computer and literature data for the rate constants of absorption, distribution and metabolism. It was found that the volume of distribution did not change with age, and the increase in biologic half-life from 22.8 hours in the young subjects to 86.62 in the elderly subjects was due to a decreased rate of metabolism. When the one-point method is used, the size of the nightly dose of amobarbital should be reduced in elderly subjects from 200 mg to 50 mg in order to maintain the same steady-state blood levels found in younger subjects.
Correlation of early reduction in the apparent diffusion coefficient of water with blood flow reduction during middle cerebral artery occlusion in rats

To determine the relationship between reductions in the apparent diffusion coefficient of water (ADC) and in cerebral blood flow (CBF) during focal ischemia, we used diffusion-weighted magnetic resonance (D-MR) imaging and autoradiographic CBF analysis to examine rats subjected to 30 or 90 min of permanent middle cerebral artery (MCA) occlusion. In the 30-min occlusion group (n = 10), the area with substantially reduced ADC (15% or more below the contralateral level [ADC 15 ]) corresponded best to the area with CBF below 25 ml/100 g/min and was significantly smaller than the area with CBF below 50 ml/100 g/min (CBF 50 ), a level associated with reduced protein synthesis and delayed necrosis (40 ± 13% versus 74 ± 8% of the ischemic hemisphere; P < 0.0001). In the 90-min occlusion group (n = 6), the ADC 15 area corresponded best to the CBF 30 to CBF 35 area and was again significantly smaller than the CBF 50 area (54 ± 13% versus 73 ± 20%, P < 0.05). Thus, the area of substantially reduced ADC at 30 and 90 min represents only 53% and 74%, respectively, of the tissue at risk for infarction. These findings indicate a potential limitation in using early D-MR imaging to predict stroke outcome.
Estimates of threshold windspeed from particle sizes in blowing snow

Abstract Particle size distributions measured in the saltation layer of drifting snow are fitted reasonably well by the two-parameter gamma function. Using these data, the mean particle size 0.25 m above the surface is predicted as a function of windspeed, from the theoretical relationship developed by Budd (1966). Average particle diameters, measured with a photoelectric snow particle counter at a site in southeastern Wyoming, U.S.A., during drifting of moderate intensity, are larger than mean sizes predicted by theory. These experiments provide empirical equations that allow threshold windspeeds for snow transport to be estimated by monitoring an anemometer and particle counter.
Dabigatran: an oral direct thrombin inhibitor for use in atrial fibrillation.

Atrial fibrillation (AF) is well known as one of the leading causes of stroke and systemic embolism. Anticoagulation therapy is recommended in all patients at moderate-to-high risk of stroke. The vitamin K antagonist warfarin has traditionally been used in these patients but presents challenges in dosing and monitoring in these patients. The oral direct thrombin inhibitor dabigatran etexilate (Pradaxa®; Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, USA) was recently approved for use in the US for preventing stroke and systemic embolism in patients with nonvalvular AF. Clinical trials have shown it to reduce the risk of stroke and systemic embolism when compared with warfarin (goal international normalized ratio [INR] 2–3) with a similar risk for severe bleeding. It can be given twice daily, with the dose adjusted for renal function. It does not have any dietary restrictions, has few drug interactions (except involving permeability [P]-glycoprotein [P-gp] agents), and does not require routine laboratory monitoring. Patients may experience significant dyspepsia with its use. Compared with warfarin there is increased risk for gastrointestinal bleeding and perhaps myocardial infarction. Currently, no reversal agent exists for use in situations of overdose or severe bleeding although some strategies have been suggested. Despite its high acquisition cost compared with warfarin, analysis using theoretical models has shown it to be cost-effective. Dabigatran offers a unique alternative to warfarin in patients with nonvalvular AF and can be beneficial in patients requiring anticoagulation therapy.
Deregulation without apology: A truncated survivor analysis of long-run efficiency gains in the U.S. trucking industry

Deregulation of the U.S. trucking industry is found to have promoted long-run technical efficiency among less-than-truckload carriers of general commodity freight. It did so by exposing all carriers to competition which caused the very largest group, hauling more than five billion ton-miles annually, to lose output share to smaller carrier groups. Their inability to survive in-full implies that efficiency gains were achieved by reducing the extent of operation under decreasing returns to scale. This conclusion conflicts with other recent findings that deregulation promoted long-run efficiency by creating new ways for all carriers, even the very largest, to achieve economies of scale. The discrepancy in conclusions is significant in that previous findings of continuous scale economies, post-deregulation, leave open the possibility of rising industry concentration with all due repercussions on consumer welfare. A more encouraging outlook emerges from the present survivor analysis which finds the minimum efficient size to be below one billion ton-miles annually. This finding strongly supports a prediction of vigorous competition in the future, at least for this one segment of the trucking industry.
Fimbria–Fornix vs Selective Hippocampal Lesions in Rats: Effects on Locomotor Activity and Spatial Learning and Memory

The behavioral effects of interrupting the axons that pass in the fimbria and dorsal fornix were compared with the effects of selective removal of the cells that comprise the hippocampus with ibotenic acid. Starting 4.5 months after surgery, lesioned and control rats were (i) trained in both the Morris water maze and the eight-arm radial maze using protocols that placed an emphasis on either working memory (WM) or reference memory (RM) and (ii) tested for locomotor activity in the home cage. In comparison to sham-operated rats, the rats from both lesion groups were impaired in most learning/memory tasks, but there were some interesting differences between the two lesioned groups. When compared to rats with fimbria-fornix lesions (FIFX rats), hippocampal rats (HIPP rats) were slower in learning to swim to a visible platform and showed a greater impairment than FIFX rats in the radial-maze task when the testing procedure required the utilization of RM and WM in a more demanding WM task. In the test of locomotor activity, FIFX and control rats did not differ, but HIPP rats were more active than the rats in both other groups. The pattern of results obtained after a 4.5-month recovery period support the following general conclusions. (1) While there are some similarities in the effects on behavior of interrupting the axons in the fimbria-fornix compared to removing the hippocampus, there are some important differences. (2) From the findings that are available, a possible explanation to account for the difference between FIFX and HIPP rats is that the 4.5-month survival time permitted some recovery in the group of rats with FIFX lesions. (3) While it is well known that the Morris water maze and the radial-arm maze tasks provide useful measures of spatial learning and memory processes, our results suggest that the information provided by the two spatial learning tasks may differ in important respects.
The ‘pocket’ porphyrins: Hemoprotein models with lowered CO affinities

Abstract A new series of hemoprotein models, the iron(II) ‘pocket’ porphyrins [1], have been synthesized (Fig.1). This series of congruent models has been designed so as to incorporate varying degrees of steric encumbrance at the gaseous ligand binding site. Throughout the series, the pockets are expected to accommodate the formation of unhindered, bent FeO2 units, while providing, in differing degrees, steric hindrance sufficient to interfere with the binding of CO in a normal linear fashion. Dilute solutions of several iron(II) ‘pocket’ porphyrin complexes in toluene are five-coordinate in the presence of excess axial ligands (1-methylimidazole and 1,2-dimethylimidazole) and are sufficiently stable with respect to oxidation so as to allow determination of and at room temperature under equilibrium conditions. Whereas the oxygenaffinities of the ferrous ‘pocket’ systems are comparable to those of the ‘picket fence’ [2] compounds, the carbon monoxide affinities are significantly lowered and approach that of myoglobin (Table I). Kinetic data indicate that the lowered CO affinities in the ‘pocket’ complexes are primarily reflected in decreased association rates. By contrast, the ‘pocket’ models show both decreased O2 dissociation and association rates as compared to the ‘picket fence’ analogues, FeTpivP(1,2-Me2Im), I, and FePiv35CIm, II. These results indicate that steric hindrance can selectively discriminate against CO binding in model compounds and support the hypothesis that the intrinsic CO affinities of hemes may be reduced by steric interaction with the binding pocket in hemoproteins [3]. A full account of this work is to be published elsewhere [1]. t001 . O2 and CO Binding to Iron Porphyrins and Hemoproteins a , b . kCOB (M−1 s−1) PCO 1 2 (torr) kO2B (M−1 s−1) PO2 1 2 (torr) Mb c [0.1 M KPi] 3–5 × 105 0.014 –0.025 1–2 × 107 0.37–1 HbA, R state c [0.05–0.1 M KPi] 4.6 × 106 0.0014 3.3 × 107 0.22 d , 0.36 e 2.9 × 106 d HbA, T state c [0.1 M KPi] 2.2 × 105 0.30 1.2 × 107 e 40 d , 140 e FePiv35Clm(II) f 3.6 × 107 2.2 × 10−5 4.3 × 108 0.58 FeMedPoc(1-Melm) (IVa) f 1.5 × 106 6.5 × 10−4 1.7 × 107 0.36 g FePocPiv(1-MeIm) (IIIa) f 5.8 × 105 1.5 × 10−3 2.2 × 106 0.36 FeTpivP(1,2-Me2Im) (I) f 1.4 × 106 8.9 × 10−3 1.1 × 108 38 FeTalPoc(1,2-Me2Im) (V) f 1.1 × 10−3 7.4 × 108 4 FeMedPoc(1,2-Me2Im) (IVb) f 2.1 × 105 0.026 5.2 × 106 12.4 FePocPiv(1,2-Me2Im) (IIIb) f 9.8 × 104 0.067 1.9 × 106 12.6 a Errors ⩽ 15%, unless otherwise indicated. b For original literature citations see references 1a and 1c. c Aqueous, pH 7.0–7.4, 20°C. d Value for α chain. e Value of β chain. f Toluene, 25°C. g −+20% error.
Serum-free media for a human lymphocyte cell line and for PWM-stimulated peripheral blood lymphocytes: Requirements for insulin, transferrin and albumin

Two simple chemically defined media are reported to support cell proliferation of a human lymphocyte cell line and of mitogenically (PWM) stimulated peripheral blood lymphocytes. The medium in the former instance is Ham's F12 supplemented with insulin, transferrin, albumin and cholesterol. In the latter case, RPMI 1640 supplemented with insulin, transferrin and albumin was found to support cell proliferation as well as fetal calf serum. There was no apparent cell cycle specificity observed for the mode of action of insulin and transferrin. A comparison of the two defined media showed that the one for the cell line was more enriched for lipids and lipid precursors.
RANK signaling pathways as potent and specific therapeutic targets for bone erosion in rheumatoid arthritis

Bone erosion is a major complication associated with rheumatoid arthritis (RA) and is a key contributing factor to the functional disability of RA patients. Tumor necrosis factor-α and interleukin-1 are well recognized as important factors causing bone erosion in RA. As such, current therapeutic regimens have relied primarily on the agents blocking the function of tumor necrosis factor-α and interleukin-1. The discovery of the receptor activator of NF-B (RANK) and its ligand (RANKL) has not only revealed an essential role for the RANKL/RANK system in arthritic bone erosion, but also indicated that the system can serve as effective therapeutic targets for arthritic bone erosion. In this review, the role of the RANKL/RANK system in bone erosion in RA, and the therapeutic agents, which are currently under development that target the system, will be discussed. Moreover, the rationale for exploring certain RANK signaling pathways as better therapeutic targets will also be discussed.
The generalized theory of perfectly matched layers (GT‐PML) in curvilinear co‐ordinates

In this paper, the generalized theory for perfectly matched layers, originally presented as a systematic development of the unsplit-field formulation of perfectly matched absorbers in cartesian co-ordinates, is extended to curvilinear co-ordinates. A special class of unstructured grids is identified, which is of interest to many practical applications, and for which the construction of perfectly matched layers is possible. The interesting case of cylindrical co-ordinates is examined separately, and several differences are identified between the way that the perfectly matched layers are constructed in this case and in the case of Cartesian co-ordinates. Numerical results from transient electromagnetic simulations on unstructured grids are used to investigate the absorbing effectiveness of the constructed perfectly matched absorbers. Copyright © 2000 John Wiley & Sons, Ltd.
Alemtuzumab for cytolytic induction of immunosuppression in heart transplant recipients

Objective—To review available evidence about the safety and efficacy of alemtuzumab for induction of immunosuppression in heart transplant recipients.Data sources—Searches of MEDLINE, EMBASE, and Cochrane databases were conducted. Key search terms included alemtuzumab, Campath-1H, CD52, lymphocyte, cytolytic, induction, immunosuppression, rejection, and cardiac transplantation. Additional pertinent data were identified through a search of abstracts from major transplant meetings.Study Selection and Data Extraction—All English-language articles and abstracts identified from the data sources were evaluated. All primary data were eligible for inclusion if they evaluated the safety or efficacy of alemtuzumab for induction of immunosuppression in heart transplant patients. One retrospective cohort, 1 case series, 1 case-control series, and 1 open-label trial were identified and included for review.Data Synthesis—Acute cellular rejection occurs in 40% to 70% of heart transplant recipients within the first 6 mon...