cssi/SciSciGPT-SciSciNet huggingface dataset:
Private Open Forums

Traditional public forums for the exercise of First Amendment rights are vanishing for four reasons: communication has migrated online, where private actors control digital spaces; private actors readily censor their forums, either for profit or at the government’s behest; public forums can be “privatized” for certain events, which permit organizers to engage in viewpoint exclusion; and the list of public forums, which the Supreme Court is loathe to expand, has never been a long one. This is a problem because the expression of First Amendment rights cannot exist in isolation, but has effect only in a larger system of interacting rights. When an individual speaks, a hearer listens, often at an organization’s event. Local press may be covering the speech, and listeners may be there in person, or tune in by television, radio, or the Internet. The legal status of the forum matters greatly because it facilitates all of these interconnected instances of First Amendment activity.This Article responds to the constitutional crisis entailed in vanishing traditional public forums and their persistent importance to First Amendment interests. It does so by proposing a “Private Open Forums” doctrine. A Private Open Forum is any space (digital, physical, or otherwise) that is privately owned; substantially open to the public; substantially non-selective/non-discriminatory; functions primarily to facilitate users’ First Amendment activities; and intended to facilitate those activities. I argue that operators of Private Open Forums constitutionally have and normatively should have the free-standing First Amendment right to maintain their forums and facilitate users’ First Amendment activities, as well as standing to defend their users’ First Amendment rights exercised on the forum.
Human immunoglobulin heavy chain genes.

genes in man, has lagged surprisingly behind similar information in the inbred mouse. The reasons for this are complicated but to some extent are related to the discovery of the myc oncogene. Thus, after genes encoding some of the constant region isotypes as well as the well defined “subgroups,”
ALGORITHMS FOR APPROXIMATE GRAPH COLORING

A coloring of a graph is an assignment of colors to the vertices so that no two adjacent vertices are given the same color. The problem of coloring a graph with the minimum number of colors is well known to be NP-hard, even restricted to k-colorable graphs for constant k $>$ 3. This thesis explores the approximation problem of coloring k-colorable graphs with as few additional colors as possible in polynomial time, focusing on the case of k = 3. For the worst-case problem, the previous best upper bound on the number of colors needed for coloring 3-colorabe n-vertex graphs in polynomial time is $O(\sqrt{n}/\sqrt{\log n})$ colors by Berger and Rompel, improving a bound of $O(\sqrt{n})$ colors by Wigderson. We present an algorithm to color any 3-colorable graph with $O(n\sp{3/8}$ polylog($n$)) colors, breaking an "$O(n\sp{1/2-o(1)})$ barrier". The algorithm presented here is based on examining second-order neighborhoods of vertices, rather than just immediate neighborhoods of vertices as in previous approaches. We extend our results to improve the worst-case bounds for coloring k-colorable graphs for constant k $>$ 3 as well. We also examine the problem of coloring random k-colorable graphs. We consider a standard model in which vertices are first randomly assigned to one of k color classes and then each edge between two vertices of different color is placed into the graph with probability p. For sufficiently high edge probability, it is known by results of Turner, Dyer and Frieze, and others, that such graphs are easy to k-color. We describe here an algorithm to k-color graphs generated in this way for a much wider range of edge probabilities (p $\geq$ $n\sp{-1+\epsilon}$ for any constant $\epsilon$ $>$ 0) than previously possible. To study a wider variety of graph distributions, we also present a model of graphs generated by the semi-random source of Santha and Vazirani that provides a smooth transition between the worst-case and random models. In this model, the graph is generated by a "noisy adversary"--an adversary whose decisions (whether or not to insert a particular edge) have some small (random) probability of being reversed. We show that even for quite low noise rates, semi-random k-colorable graphs can be colored with high probability using just k colors. Finally, we use assumptions about the worst-case difficulty of approximate graph coloring to provide lower bounds for other hard problems. Using techniques developed by Berman and Schnitger, we show that if there is no polynomial-time algorithm to color k-colorable graphs with $O(\log n)$ colors, then the largest independent set in a graph (or equivalently the largest clique) cannot be approximated to within a factor of $n\sp{1-\epsilon}$ for any constant $\epsilon$ $>$ 0. This is a much higher lower-bound than achieved by previous results, albeit based on less solid assumptions. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Modeling Success: Using Preenrollment Data to Identify Academically At‐Risk Students

Improving student success and degree completion is one of the core principles of strategic enrollment management. To address this principle, institutional data were used to develop a statistical model to identify academically at-risk students. The model employs multiple linear regression techniques to predict students at risk of earning below a 2.0 grade point average (GPA) in their first semester of college. Data analysis from student cohorts starting in the Fall 2007 through Fall 2009 (N = 11,644) identified two groups of students—one predicted to earn less than a 2.0 and the other predicted to earn a 2.0 or higher. The first semester college GPA and retention rates of both groups of students were tracked to examine the accuracy of the model in predicting student success and subsequent retention rates. Multi-year analyses illustrates that the model can be used to identify students who are at risk of earning less than a 2.0 GPA. Additional analysis demonstrates there is a relationship between predicted and actual first semester GPA and retention rates. Since the data used to develop the model are commonly available at most institutions, this study provides a practical approach for the SEM research professional to identify potentially academically at-risk students, which subsequently can be used to assist students and improve student success and degree completion.
Transaction cost economics: The comparative contracting perspective

Abstract Gregory Dow's assessment of transaction cost economics is both thoughtful and provocative. Although we agree on many matters, these remarks focus on our differences. I begin with a brief sketch of the framework out of which transaction cost economics operates. I then examine the purported bias of transaction cost economics in favor of capital managed as against labor managed firms and my alleged failure to deal with ‘downward opportunism’. Dow's claim that transaction cost economics is given to functionalist excesses is considered next. Concluding remarks follow.
Mandatory Fun: Consent, Gamification and the Impact of Games at Work

In an effort to create a positive experience at work, managers have deployed a wide range of initiatives and practices designed to improve the affective experience for workers. One such practice is gamification, introducing elements from games into the work environment with the purpose of improving employees’ affective experiences. Games have long been played at work, but they have emerged spontaneously from the employees themselves. Here, we examine whether managerially-imposed games provide the desired benefits for affect and performance predicted by prior studies on games at work or whether they are a form of “mandatory fun.” We highlight the role of consent (Burawoy, 1979) as a psychological response to mandatory fun, which moderates these relationships and, in a field experiment, find that games, when consented to, increase positive affect at work, but, when consent is lacking, decrease positive affect. In a follow up laboratory experiment, we also find that legitimation and a sense of individual agency are important sources of consent.
Interleukin-10 Inhibits Expression of Both Interferon – and Interferon γ– Induced Genes by Suppressing Tyrosine Phosphorylation of STAT1

Interleukin-10 (IL-10) helps maintain polarized T-helper cells in a T-helper lymphocyte 2 (Th2) phenotype. Part of this process involves the prevention of the development of Th1 cells, which are a primary source of interferon γ (IFNγ), a potent activator of monocytes and an inhibitor of Th2 proliferation. Because monocytes and macrophages are important mediators of Th1-type responses, such as delayed-type hypersensitivity, we sought to determine if IL-10 could directly mediate inhibition of IFNγ- and IFN-induced gene expression in these cells. Highly purified monocytes were incubated with IL-10 for 60 to 90 minutes before the addition of IFNγ or IFN. IL-10 preincubation resulted in the inhibition of gene expression for several IFN-induced genes, such as IP-10, ISG54, and intercellular adhesion molecule-1. The reduction in gene expression resulted from the ability of IL-10 to suppress IFN-induced assembly of signal transducer and activator of transcription (STAT) factors to specific promoter motifs on IFN- and IFNγ-inducible genes. This was accomplished by preventing the IFN-induced tyrosine phosphorylation of STAT1, a component of both IFN- and IFNγ-induced DNA binding complexes. Therefore, IL-10 can directly inhibit STAT-dependent early response gene expression induced by both IFN and IFNγ in monocytes by suppressing the tyrosine phosphorylation of STAT1. This may occur through the ability of IL-10 to induce expression of the gene, suppressor of cytokine signaling 3 (SOCS3).
"For the hatching of our hearts": friendship, pastoral care, and the formation for ministry.

The author explores the notion of friendship by drawing on personal and ministry experience, as well as on philosophical and biblical insights, in order to suggest a dynamic practice of pastoral care and a process of ministry formation which transcends the professional paradigm and the peership principle. He suggests that the power to bless, the ability to extend grace, and the potential for change are dynamics of friendship which are effective both in pastoral care and in ministry formation.
Error-free, 12-user, 10 Gbit/s/user O-CDMA network testbed without FEC

Error-free operation of a 12 x 10 Gbit/s synchronous, time-slotted spectral phase-encoded time-spreading optical code division multiple access (O-CDMA) network testbed without using forward-error-correction (FEC) is demonstrated. A nonlinear optical loop mirror time gate and nonlinear thresholding minimise multiuser interference.
Etiologic heterogeneity of fetal hydrocephalus diagnosed by ultrasound

Increased use of fetal ultrasound imaging by obstetricians has led to an increased rate of in utero detection of fetal malformations. Eight patients referred for level II sonography for confirmation of suspected fetal hydrocephalus were found to have affected fetuses. Examination of the resulting fetuses and infants revealed remarkable etiologic heterogeneity for the hydrocephalus. The risk for recurrence of hydrocephalus and other malformations in future offspring of these mothers varies from negligible to 25%. This experience emphasizes that there are many causes of fetal hydrocephalus and that careful diagnostic studies must be performed on any fetus or infant found to have hydrocephalus, so that accurate genetic counseling can be provided to the family.
Nuclear magnetic resonance spectra of benzylsilanes and phenyldisilanes

Abstract NMR spectral data for a series of substituted benzyldimethylsilanes (I) and phenyltetramethyldisilanes (II) are reported. 29 SiH and 13 CH coupling constants are shown to be correlated by Hammett σ constants. The data are discussed in terms of mechanisms of transmission of substituent effects across C—Si and Si—Si bonds. A good Hammett correlation is also found of J ( 13 CH) for the benzylic protons of a series of substituted toluenes.
Indices for mid-latitude North Pacific winter wind systems; an exploratory investigation

Biological distributions and fish migrations during the spring and summer in the mid-latitude N Pacific are believed to be affected by the large-scale wind systems during the preceding winter. These wind systems are related to the field of atmospheric pressure which, on a monthly or quarterly time scale, show pronounced interannual variations. This exploratory investigation is concerned with measures of the large-scale wind systems that are indicative of their intensity, location, and size, and that can be derived from monthly or quarterly sea-level pressure distributions. Of interest are the NW, W, and SW wind systems which are related to the pressure gradients between the Siberian High and Aleutian Low, the Aleutian Low and the N Pacific Subtropical High, and the Aleutian Low and the N American High, respectively. Interannual changes in the winter sea-level pressure distribution pattern are primarily the result of changes in the pressure and zonal displacements of the Aleutian Low near 50°N. This property permitted simple derivation of wind indices from grid values of N hemisphere mean winter pressures distributions for the years 1947 to 1985. Indices, presented as normalized anomalies, are for the meridional component of the wind system at 50°N over the ocean W and E of the Aleutian Low, for the westerlies S of the Aleutian Low and for the longitude of this Low. The paper concludes with a discussion of the limitations of the indices in terms of reflecting characteristic atmospheric pressure distribution patterns, an examination of the relationship between wind anomalies and El Nino events, and a discussion of the results in terms of oceanographic, climate, and biological implications.
Coupling capillary electrochromatography with mass spectrometry by using a liquid-junction nano-spray interface.

Abstract Capillary electrochromatography (CEC) was coupled with mass spectrometry (MS) for the separation of some selected pesticides and drug enantiomers. CEC separations were carried out in fused silica capillaries packed with either 5 μm RP 18 silica or 5 μm silica modified vancomycin particles. The capillary column was connected with the MS utilizing a laboratory-made liquid-junction interface equipped with a 50 μm I.D. capillary-tip positioned at a few mm from the orifice of the MS. The CEC–MS set-up was operated without external pressure assistance during the electrochromatographic run commonly used to avoid bubble formation. However a hydrostatic pressure of a few kPa was applied only to the liquid-junction interface to optimize the ion-spray due to the low I.D. of the capillary-tip. In order to optimize the CEC–MS method, several experimental parameters were studied, namely the inlet pressure, the hydrostatic pressure into the liquid-junction interface, the type of sheath-liquid and the mobile phase. The application of an inlet pressure influenced only analyte retention times that were shortened by increasing the pressure. On the contrary the hydrostatic pressure applied to the interface increased the flow rate into the tip also increasing the ion-signal recorded in the mass spectrometry. The ion-signal raised almost linearly by increasing the outlet pressure till 3.5 kPa and then decreased. The separation of the selected pesticides was not influenced at all changing the hydrostatic pressure on the interface. Some basic enantiomeric compounds of pharmaceutical interest were successfully separated by CEC achieving good resolution. They were detected by MS with limit of detection in a range of 0.24–0.60 μg/mL.
Systemic Endocrine Instigation of Indolent Tumor Growth Requires Osteopontin

The effects of primary tumors on the host systemic environment and resulting contributions of the host to tumor growth are poorly understood. Here, we find that human breast carcinomas instigate the growth of otherwise-indolent tumor cells, micrometastases, and human tumor surgical specimens located at distant anatomical sites. This systemic instigation is accompanied by incorporation of bone-marrow cells (BMCs) into the stroma of the distant, once-indolent tumors. We find that BMCs of hosts bearing instigating tumors are functionally activated prior to their mobilization; hence, when coinjected with indolent cells, these activated BMCs mimic the systemic effects imparted by instigating tumors. Secretion of osteopontin by instigating tumors is necessary for BMC activation and the subsequent outgrowth of the distant otherwise-indolent tumors. These results reveal that outgrowth of indolent tumors can be governed on a systemic level by endocrine factors released by certain instigating tumors, and hold important experimental and therapeutic implications.
ADAPTIVE FEATURES OF THE FORE LIMB IN PRIMITIVE TETRAPODS AND MAMMALS

The primitive form of the limb in early synapsid reptiles, ancestral to the therapsid and mammalian line, is illustrated by the skeleton of the left fore limb of the pelycosaur Ophiacodon (Fig. 1). The figure shows several features of mechanical importance: (1) The humerus is heavy, broad, short, and held horizontally from the body; it has a horizontal ridge-like proximal articular surface, two separate distal articular facets, and two greatly expanded epicondyles, of which the ectepicondyle stands erect dorsally and the entepicondyle stands out like a shelf posteriorly. (2) The radius and ulna articulate separately with the humerus, but not at all with each other; their movements were not confined to a single plane (with reference to the humerus) but were (a) extension (laterad) and flexion (mediad), and (b) elevation and depression. (3) The pisiform bone is seen to bear the same relation-
Structured Bit-Interleaved LDPC Codes for MLC Flash Memory

Due to a structural feature in the programming process of MLC (two bits per cell) and TLC (three bits per cell) flash memory, the majority of errors that occur are single-bit errors. Moreover, the voltages used to store the bits typically result in different bit error probabilities for the two or three types of bits. In this work we analyze binary regular LDPC codes in the standard bit-interleaved coded modulation implementation, assuming different probabilities on the bits, to determine what ratio of each type of bit should be connected at the check nodes to improve the decoding threshold. We then propose a construction of nonbinary LDPC codes using their binary images, resulting in check node types that come close to these optimal ratios.
The effect of particle size distribution on dissolution rate and oral absorption

Abstract A computer method has been devised to describe the theoretical dissolution rate of a polydisperse powder under non-sink conditions based on its percent weight particle size distribution. This method was used to estimate the particle size distribution of drug contained in 3 capsule formulations which differed only in the extent of milling of drug used to make the capsules. These distributions served to demonstrate the effect of milling on dissolution rate and were used to simulate their effect on the amount of drug absorbed orally.
Assessment of a thermoviscoplastic model of upset welding by comparison to experiment

Abstract An experimental investigation of upset welding has been integrated into an effort to develop a mathematical model of transient, hot forming processes. The experimental apparatus provided sufficiently accurate and complete data for the detailed comparisons necessary to assess the performance of a process model. An existing thermomechanical model, which utilized the finite-element method to solve the governing equations, was modified to include a simple scheme of mesh repair based on convective adjustment. The mechanical material model assumed purely viscoplastic behavior. All material properties and constants were evaluated from independent tests. Measured boundary conditions were used as input to the model and the process was simulated for three cases of differing geometry. Predicted temperatures and voltages were in excellent agreement with measured values. Predicted axial displacements were in good agreement. The limitations of the material model were clearly identified by the comparisons of the predicted to the measured variables.
Geographic Flows of Hired Agricultural Labor: 1957–1960

Data obtained from Social Security Administration records are used to examine whether hired agricultural labor moving from one census region to another within the United States is responsive to economic phenomena. The unique feature of the analysis is its access to data describing gross flows of hired agricultural labor among these regions rather than having to rely on observations of net changes in the quantity of such labor. The general conclusion is that hired agricultural workers are responsive to economic phenomena in the directions suggested by formal economic theory but that interregional movement of such workers is greatly hampered by the presence of artificial barriers to mobility.
Sacroplasty for cancer-associated insufficiency fractures.

BACKGROUND Tumor-associated sacral insufficiency fractures (SIF) present a significant clinical challenge. As survival increases for many malignancies, sacral fractures associated with metastases, sacral or extended pelvic radiation, and paraneoplastic osteoporosis are increasingly common and yet remain difficult to treat in the setting of the potentially significant morbidity of open sacral surgery. OBJECTIVE To describe our prospective experience with sacroplasty for tumor-associated lesions, including the largest series to date of radiation-induced SIF. METHODS Twenty-five patients with symptomatic SIF underwent 31 percutaneous fluoroscopy-guided sacroplasties with a median 5.8 mL of polymethyl methacrylate or a ceramic-resin composite under fluoroscopic guidance and with concurrent biopsy acquisition. Eighteen patients had fractures related to previous sacral or pelvic radiation; 4 had viable lytic lesions; and 2 had oncology-related osteoporosis. Postoperative pain reduction, procedural morbidity, and functional outcomes were recorded. RESULTS Twenty of 25 patients (80%) had reduction in their visual analog pain score at a median follow-up of 6.5 months; no patients worsened. The mean visual analog scale score decreased from 8.8 to 4.7 postprocedurally (P < .001), with significant reductions regardless of the underlying pathology (P < .001 to P < .05). Six of 13 patients with pretreatment ambulatory impairment required fewer ambulatory aids and 3 were newly ambulatory. Extravertebral cement migration was noted in 18 procedures; however, no instance was clinically relevant. Six repeat or contralateral procedures were performed. No morbidity was encountered. CONCLUSION Sacroplasty is a safe and effective option for the palliation of sacral fractures in the oncologic population.
An authorization mechanism for a relational data base system

A multi-user data base system must permit users to selectively share data, while retaining the ability to restrict data access. There must be a mechanism to provide protection and security, permitting information to be accessed only by properly authorized users. Further, when tables or restricted views of tables are created and destroyed dynamically, the granting, authentication, and revocation of authorization to use them must also be dynamic. We discuss each of these issues and their solutions in the context of the relational data base management system, System R.When a data base user creates a table, he is fully and solely authorized to perform actions upon it such as read, insert, update, and delete. If he wishes, he may explicitly grant to any other user any or all of his privileges on the table. In addition, he may specify that that user is authorized to further grant these privileges to other users. The result is a directed graph of granted privileges originating from the table creator.At some later time, a user A may revoke some or all of the privileges which he previously granted to another user B. This action usually revokes the entire subgraph of the grants originating from A's grant to B. It may be, however, that B will still possess the revoked privileges by means of a grant from another user C, and therefore some or all of B's grants should not be revoked. We discuss this problem in detail and present an algorithm for detecting exactly which of B'S grants should be revoked.Because revocation may be performed dynamically, a user's authorization for a table must be checked dynamically. We present a scheme which attempts to minimize the cost of such revalidation.
Acanthamoeba castellanii: Characterization of an Adhesin Molecule☆

Acanthamoeba castellanii is a free-living protozoan that causes keratitis in humans and has been associated with pneumonia and granulomatous amebic encephalitis in dogs, sheep, and other species. Adherence of the Acanthamoeba to epithelial cells is critical to the pathogenesis of this disease. In this study, several mouse monoclonal antibodies (MAb) generated to whole Acanthamoeba trophozoites identified surface membrane epitopes by ELISA and IFA. Nine antibodies inhibited adherence of [(35)S]-methionine-labeled Acanthamoeba trophozoites to hamster corneal epithelial cells by 27-90%. Sodium periodate treatment, but not proteinase K digestion, of whole Acanthamoeba destroyed epitopes recognized by adherence-inhibiting antibodies such as MAb 7H6, suggesting that the adherence epitopes are carbohydrates. Other antibodies, MAb 2A8 for example, recognized surface membrane peptide epitopes that were proteinase K sensitive and sodium periodate resistant. Purified MAb 2A8 was used in an antigen-capture ELISA with peroxidase-labeled MAb 7H6 and demonstrated that the carbohydrate adhesion molecule was linked to the peptide recognized by MAb 2A8. Both MAbs 7H6 and 2A8 recognized a >207-kDa band on a Western blot of eluant from a MAb 2A8 immunoaffinity column, confirming that MAb 7H6 and MAb 2A8 recognize different epitopes on the same adherence molecule. MAbs 7H6 and 2A8 also identified the adhesion molecule in soluble Acanthamoeba membrane preparations and MAb 2A8 immunoaffinity column eluant by ELISA and Western blot. Neither of these antibodies were inhibited from binding to whole trophozoites nor membrane extracts by mannose or mannan in competitive binding assays. When our Acanthamoeba membrane preparations were electrophoresed and immunoblotted with alpha-d-mannosylated-biotin albumin, no bands were recognized in the >207 kDa range by our adherence-associated antibodies. These results suggest that the Acanthamoeba adhesin is not identical to the mannose binding protein of Acanthamoeba but rather is a distinct surface membrane glycoprotein.
High Sensitivity Measurements of the Scattering Dispersion of Phantoms using Spectral Domain Optical Coherence Tomography

We demonstrate a novel technique to determine the size of Mie scatterers with high sensitivity. Our technique is based on spectral domain optical coherence tomography measurements of the dispersion that is induced by the scattering process. We use both Mie scattering theory and dispersion measurements of phantoms to show that the scattering dispersion is very sensitive to small changes in the size and/or refractive index of the scatterer.
Particle acceleration during substorm growth and onset

ISEE-1 observations of ion and electron energization made at 11 RE during a substorm event on April 2, 1978 are presented. An analysis of the dominant cross-tail current systems in this event (Mitchell et al., 1990) has made it possible to uniquely associate particle energization processes with the development and/or disruption of the cross-tail currents. It is found that significant ion acceleration occurs as the ions participate in serpentine cross-tail motion (Speiser, 1965), establishing the dominant plasma sheet current system just prior to onset. As this current disrupts, the magnetic field configuration dipolarizes and further ion energization and the bulk of the electron energization occurs. During dipolarization energization is due primarily to the inductive electric field, including betatron and Fermi acceleration processes.
An efficient, optical fiber-based waveguide interface to a single quantum dipole

We theoretically investigate a single emitter embedded in an optical waveguide providing highly efficient, optical fiber access to the dipole. Photoluminescence collection above 70 % and 15 dB transmission contrast upon resonant excitation are predicted.
Michael Polanyi: the anthropology of intellectual history

Scientific and political developments of the early twentieth century led Michael Polanyi to study the role of the scientist in research and the interaction between the individual scholar and the surrounding conditions in community and society. In his concept of “personal knowledge” he gave the theory and history of science an anthropological turn. In many instances of the history of sciences, research is driven by a commitment to beliefs and values. Society plays the role of authority and communicative backdrop that presupposes individual liberty. As a system of beliefs science is rooted in community and also in history. However, as soon as fellow humans become the objects of research, their appeal transcends the researcher. Consequently, the history of human endeavor reveals a “firmament” of standards and obligations which represent an ontological reality, for which Polanyi invokes Teilhard de Chardin’s notion of noosphere.
ConfChem Conference on Case-Based Studies in Chemical Education: One Story, Different Classes–Using the Same Case Study for Different Levels of Chemistry Students

Many of the situations, problems, and content discussed in case studies are appropriate for multiple levels of students. Often, the same setup "story" can be used for beginning, advanced, and non-chemistry major students by varying the questions and expected sophistication for the answers. Learning outcomes can be used to guide the development of the question section of the case study, allowing the case to be accessible to different levels of students. The same case can be used for chemistry majors and nonmajors; upper level and introductory courses; and large and small classes. Published cases can be tailored to another course by considering placement in the course, level of questions, and resources given to students.
Improved medium and culture conditions for clonal growth with minimal serum protein and for enhanced serum-free survival of Swiss 3T3 cells

Improved culture conditions have been developed that will support clonal growth of Swiss mouse embryo 3T3 cells at concentrations of serum protein at low as 125 micrograms/ml. Survival of the cells under completely protein-free conditions also is enhanced greatly. The improvements that made these results possible include: (a) use of medium MCDB 402, which was developed specifically for Swiss 3T3 cells by adjusting the concentrations of all components of Dulbecco's modified Eagle's medium to optimum values for clonal growth with minimal serum protein and by adding other nutrients such as trace elements and "nonessential" amino acids that were not in the original formula; (b) use of culture surfaces that are coated with a positively charged polymer, poly-D-lysine; and (c) use of gentle low temperature trypsinization technique that minimizes cellular damage and the need to neutralize residual trypsin.
Renal and hemodynamic responses to bumetanide in hypertension: effects of nitrendipine.

Renal and hemodynamic responses to bumetanide in hypertension: Effects of nitrendipine. The effects of a calcium antagonist on the response to a loop diuretic were tested in eight hypertensive patients while they received 120 mmol · 24 hr -1 of dietary Na. Nitrendipine (N; 20 mg) or placebo (P) was administered twice daily for five days and bumetanide (B; 1 mg, i.v.) for the last three days of each period. Cardiac index (CI) was measured during tilt. B alone significantly (P Aldo ) only during P (P, 4.4 ± 1.3 to 7.6 ± 1.0; P -1 ; NS). B increased Na excretion without changing GFR or RPF; this was followed by 18 hours of decreased renal Na excretion. These actions were unchanged by N. N did not change the cumulative excretion of B (P, 268 ± 35 vs. N, 217 ± 21 µg) or the relationship between Na excretion and the log of B excretion. However, Na excretion was increased (P Aldo without modifying the rise in PRA; 3) does not change B kinetics or dynamics or the post-diuretic period of renal Na retention; 4) causes negative Na balance which is additive with that produced by B.
Opioid Medication and Sleep-disordered Breathing

There has been a growing recognition of chronic pain that may be experienced by patients. There has been a movement toward treating these patients aggressively with pharmacologic and nonpharmacologic modalities. Opioids have been a significant component of the treatment of acute pain, with their increasing use in cases of chronic pain, albeit with some controversy. In addition to analgesia, opioids have many accompanying adverse effects, particularly with regard to stability of breathing during sleep. This article reviews the existing literature on the effects of opioids on sleep, particularly sleep-disordered breathing.
On interactions between imperfections in cellular solids

A number of studies have indicated that imperfections in cellular solids can have a very large influence on their mechanical behavior. Waviness in cell walls can drastically reduce elastic stiffnesses, and various irregularities can reduce the effective strengths by large factors. These imperfections have in many instances been studied in isolation, i.e., only a singe type of imperfection was studied at a time. The goal of the present paper is to shed light on how different kinds of imperfections interact. There is a potential risk that when multiple kinds of imperfections are present, the mechanical properties of the cellular solid are worse than what would be predicted from each one in isolation. The present study is focused on linear elastic properties, although many of the conclusions apply also for other properties. The method employed is based on statistical averages and Taylor expansion arguments. Such techniques have in previous papers been applied to a single imperfection type. The conclusion from the present analysis is that, up to the third order in “small” parameters describing the severity of the imperfections, there is no interaction between a number of different types of imperfections.
Assessment of Stenosis: Implications of Variability of Doppler Measurements in Normal-appearing Carotid Arteries

PURPOSE: To examine the variability of Doppler measurements along the extracranial courses of the nondiseased common carotid artery (CCA) and internal carotid artery (ICA) and determine the effect of this variability on assessment of carotid arterial stenosis. MATERIALS AND METHODS: During the study period, 580 patients were referred for carotid arterial ultrasonography (US), including Doppler measurements of flow velocities in the proximal, middle, and distal portions of the CCA, in the bulb, and in the proximal and distal portions of the ICA. Eighty-five patients (average age, 59 years) with normal ICAs and CCAs formed the cohort for this study. RESULTS: The range of peak systolic velocity (PSV) measurements (maximum minus minimum) averaged 20 cm/sec ± 13 in the CCA and 15 cm/sec ± 13 in the ICA. ICA/CCA velocity ratios varied, depending on the CCA measurement location. In five arteries, PSV ratios exceeded a threshold of 1.8 (suggesting ≥60% stenosis); in 23 arteries, end diastolic velocity ratios exce...
Genomic Perspectives on Probiotic Lactic Acid Bacteria

The lactic acid bacteria are Gram-positive fermentative microorganisms known primarily for their roles as starter cultures and probiotics. The food industry represents one of the largest manufacturing industries in the world and recent trends are rapidly expanding the use of probiotic cultures within functional foods. Understanding and control of lactic acid bacteria is now being revolutionized by genomic sciences and the appearance of the complete genome sequences for Bifidobacterium longum, Lactobacillus johnsonii, Lactobacillus plantarum, and draft sequences for Lactobacillus gasseri and Lactobacillus casei. This explosion of DNA sequence information, accompanied by the development of bioinformatic tools for nucleic acid and protein analysis, now allows rapid characterization of the lactic acid bacteria for their genomic content and expression profiles across the entire genome. Comparative genomics has already revealed important similarities and differences in strains, species, and genera and will likely identify key genetic features responsible for the beneficial properties ascribed to probiotic lactic acid bacteria. Practical genomics for the lactic acid bacteria promises to establish the genetic landscape, correlate genotypes with desirable phenotypes, establish genetic criteria for strain selection, improve culture stability by stress preconditioning, provide opportunities for metabolic engineering, and uncover a mechanistic basis for the beneficial activities of probiotics when delivered in various foods. This presentation will examine the genomic content of probiotic Lactobacillus cultures, compared to those lactic acid bacterial genomes that have appeared recently. In addition, expression profiling by whole genome microarrays will be used to illustrate how environmental conditions encountered during biomanufacturing, fermentation, and the gastrointestinal tract can impact gene expression and culture functionality.
Congestion Control Based on Channel Occupancy in Vehicular Broadcast Networks

Cooperative vehicle safety (CVS) systems rely on vehicular ad-hoc networks operating in broadcast mode to deliver vehicle tracking and safety information to neighboring cars. This information is used to enable collision avoidance and warning systems. One of the main challenges of the eventual large scale deployment of such systems is network congestion, which could critically degrade the quality of a CVS system. In this paper, we present a method for congestion monitoring and control based on limited feedback from the network. We study the relationship between channel occupancy, as a readily available feedback measure, controllable network parameters, and network performance. We describe a performance measure relevant to CVS systems and present a congestion control method, based on channel occupancy measurements, that robustly maintains the system performance near optimal operation points. We examine the convergence properties of the congestion control algorithm and provide guidelines for the design of such systems based on network and traffic density conditions. Through simulation experiments we show significant gains in performance when closed loop congestion control methods are applied.
Bias in Filter-Based Aerosol Light Absorption Measurements Due to Organic Aerosol Loading: Evidence from Laboratory Measurements

Light absorption by soot or nigrosin dye aerosol particles were measured in the laboratory using a particle soot absorption photometer (PSAP) and a photo-acoustic spectrometer (PAS) to assess the influence of non-absorbing organic aerosol (OA) on the PSAP measurements. For the PSAP, particle light absorption is measured after collection on a filter, whereas for the PAS light absorption is measured while the particles remain suspended in the gas phase. OA was generated from the reaction of α -pinene with ozone. It was observed that the presence of this OA in an external mixture of absorbing aerosol and OA can cause an increase in the light absorption measured by the PSAP, relative to that measured by the PAS, by more than a factor of two. This enhancement in the PSAP absorption was found to increase as the amount of OA increased relative to the absorbing compound. Additionally, experiments where absorbing aerosol was deposited on a PSAP filter prior to addition of OA demonstrated that the non-absorbing OA ...
Hyperbaric oxygen preconditioning protects skin from UV-A damage

Hyperbaric oxygen therapy (HBOT) is used for a number of applications, including the treatment of diabetic foot ulcers and CO poisoning. However, we and others have shown that HBOT can mobilize cellular antioxidant defenses, suggesting that it may also be useful under circumstances in which tissue protection from oxidative damage is desired. To test the protective properties of hyperbaric oxygen (HBO) on a tissue level, we evaluated the ability of a preconditioning treatment regimen to protect cutaneous tissue from UV-A-induced oxidative damage. Three groups of hairless SKH1-E mice were exposed to UV-A 3 days per week for 22 weeks, with two of these groups receiving an HBO pretreatment either two or four times per week. UV-A exposure increased apoptosis and proliferation of the skin tissue, indicating elevated levels of epithelial damage and repair. Pretreatment with HBO significantly reduced UV-A-induced apoptosis and proliferation. A morphometric analysis of microscopic tissue folds also showed a significant increase in skin creasing following UV-A exposure, which was prevented by HBO pretreatment. Likewise, skin elasticity was found to be greatest in the group treated with HBO four times per week. The effects of HBO were also apparent systemically as reductions in caspase-3 activity and expression were observed in the liver. Our findings support a protective function of HBO pretreatment from a direct oxidative challenge of UV-A to skin tissue. Similar protection of other tissues may likewise be achievable.
“Anomalous” oxide growth during transient-temperature oxidation of zircaloy-4

Oxidation tests of Zircaloy-4 pressurized water reactor tube specimens in steam were conducted for several types of temperature excursions. These tests were used to evaluate the accuracy of predictions of the oxidation behavior based on ideal models that employ isothermal kinetic data. While oxidation during simple transient temperature excursions, where the peak temperature was between 1000 and 1400°C, could be predicted with reasonable accuracy, certain “two-peak” transients resulted in oxide layers considerably less than those anticipated. On the basis of our experiments, we propose that this effect is related to the manner in which the monoclinic-tetragonal phase transformation occurs in the oxide and the fact that the normal (bulk) transformation hysteresis is altered for a growing oxide film.
Do over‐the‐counter analgesics reduce delayed onset muscle soreness and serum creatine kinase values?

The purpose of this study was to determine whether aspirin or acetaminophen would significantly reduce delayed onset muscle soreness (DOMS) and blood levels of creatine kinase (CK), a marker of muscle tissue damage, after an unaccustomed bout of, eccentric exercise. Thirty‐six untrained men were randomly assigned to an aspirin (3.0 g/day), acetaminophen (3.0 g/day), or placebo group in a double‐blind fashion. Drug or placebo administration began 48 hours before exercise and continued to 72 hours after exercise. Each subject performed the eccentric phase of a supine bench press at a resistance equivalent to 120% of maximum concentric strength, 1 RM (4 sets, 12 repetitions/set). A subjective sensation score of DOMS (1 = normal, 10 = very sore) and serum CK activity were measured before and at 24, 48, 72, 96, and 120 hours after exercise, using a repeated measures ANOVA. No significant group differences (p > 0.05) were found in perception of soreness; a significant time effect was observed (p <, 0.05) with p...
DIFFERENTIAL EXPRESSION OF SODIUM CHANNELS AND NICOTINIC ACETYLCHOLINE RECEPTOR CHANNELS IN NNR VARIANTS OF THE PC12 PHEOCHROMOCYTOMA CELL LINE

An important component of neuronal differentiation is the tightly controlled expression of a spectrum of ion channel proteins. Ion channels play a critical role in the generation and propagation of action potentials as well as in the cellular response to neurotransmitters, and thus are central in the transfer and integration of information in the nervous system. A model system amenable to analysis of ion channel expression and neuronal differentiation is the rat pheochromocytoma (PC12) cell line. Here, we have used electrophysiological and molecular biological approaches to analyze the expression of voltage-dependent sodium (Na) channels and nicotinic acetylcholine receptors (nAChR) in mutagenized variants (nnr cells) of the PC12 cell line. Our data reveal striking differences in the expression of these channels when compared to wild-type PC12 cells. Even in the absence of nerve growth factor (NGF), nnr cells express functional Na channels and Na channel mRNA at levels exceeding those in wild-type PC12 cells differentiated with NGF. In contrast, acetylcholine-induced currents were evident in only a small proportion of cells, presumably due to the altered pattern of expression of mRNAs encoding individual nAChR subunits. The altered ion channel expression in these variants provides an avenue for analyzing Na channel and nAChR channel function, as well as for identifying mechanisms governing their expression.
Dynamically orthogonal field equations for continuous stochastic dynamical systems

Abstract In this work we derive an exact, closed set of evolution equations for general continuous stochastic fields described by a Stochastic Partial Differential Equation (SPDE). By hypothesizing a decomposition of the solution field into a mean and stochastic dynamical component, we derive a system of field equations consisting of a Partial Differential Equation (PDE) for the mean field, a family of PDEs for the orthonormal basis that describe the stochastic subspace where the stochasticity ‘lives’ as well as a system of Stochastic Differential Equations that defines how the stochasticity evolves in the time varying stochastic subspace. These new evolution equations are derived directly from the original SPDE, using nothing more than a dynamically orthogonal condition on the representation of the solution. If additional restrictions are assumed on the form of the representation, we recover both the Proper Orthogonal Decomposition equations and the generalized Polynomial Chaos equations. We apply this novel methodology to two cases of two-dimensional viscous fluid flows described by the Navier–Stokes equations and we compare our results with Monte Carlo simulations.
Static and Dynamic Var Compensation in System Planning

This paper presents a comprehensive method for planning reactive compensation in power systems so as to maintain voltages in acceptable ranges during contingencies. The methodology allows the addition of further VAR compensation as may be economically justified. Reactive compensation considered consists of conventional shunt reactive compensation, synchronous condensers, as well as variable shunt reactive control devices called static VAR control devices. This work combines VAR optimization with static as well as with dynamic system performance evaluations. Necessary modelling of static VAR control devices for inclusion in dynamic performance programs is also given.