cssi/SciSciGPT-SciSciNet huggingface dataset:
Is Twitter a Pedagogical Tool in Higher Education? Perspectives of Education Graduate Students

This study presents the perspectives of education graduate students of using Twitter as a pedagogical tool for 15 weeks as a required social media activity in class. The results indicated that each course participants reported a positive learning experience of using Twitter. Although this was their first experience with Twitter, participants reported that Twitter provided space and opportunities to engage in academic activities as a new pedagogical tool. Participants reported they used Twitter to receive immediate and frequent course information, ask questions to the mentor, update course assignment, and to share helpful information from outside the text book to their fellow classmates and mentor. This study also highlights suggestions and implication of Twitter in personal and professional developments.
Inflation, real returns and capital investment

We find evidence for the hypothesis of Mundell (1963) and Tobin (1965) that the expected real return component of interest rates is negatively related to the expected inflation component. In the Mundell-Tobin model, the variation in expected real returns is caused by the variation in expected inflation. Our evidence suggests, however, that the variation in expected real returns is more fundamentally an outcome of the capital expenditures process. Equilibrium expected real returns vary directly with capital expenditures in order to induce equilibrium allocations of resources between consumption and investment. This positive relation between expected real returns and real activity, which comes out of the real sector, combines with a negative relation between expected inflation and real activity, which is traced to the monetary sector, thus inducing the negative relation between expected inflation and expected real returns predicted by Mundell and Tobin but explained in terms of a model much different from theirs.
Discrete Memoryless Interference Channel: New Outer Bound

A new outer bound for the two-user discrete memoryless interference channel is presented. This bound establishes the capacity region of the binary erasure interference channel, whose determination was left open in the work of Vanroose and van der Meulen (1991). The new bound is compared with the best known outer bounds for some additional examples. It is also shown that the new outer bound is tight for a one-sided deterministic interference channel that belongs to the class studied by El Gamal and Costa.
Industrial Market Behaviour and the Technological Life Cycle

The product life cycle is the cornerstone to understanding product/market behaviour, but it is not well suited to the analysis of industrial markets. In the industrial marketplace technology can be isolated as the dominant variable, explaining variations in sales over time for a product category. New “high‐tech” firms must make the critical decision early in their life as to whether to follow their technology through its life cycle, adapting to the needs of each stage it goes through, or whether to specialise in one particular stage of technology and continually develop new products to replace those that progress to later stages of the technological life cycle.
Male to female ratios for broiler‐type and egg production‐type breeders 1

Synopsis Two experiments using commercial broiler‐type breeders and one experiment using commercial egg production‐type breeders were conducted to determine the effect of male to female ratios on fertility and hatchability. Breeding pens were made up with 36 females and 4, 3, 2 or 1 male(s) per pen giving ratios of one male to 9, 12, 18 and 36 females. Five replicate pens were used per treatment. Within the ratios and genetic strains used, maximum fertility was obtained with male to female ratios of 1 to 12 with broiler‐type breeders and 1 to 18 with egg production‐type breeders. It is concluded that using fewer females per male than in these ratios would be unwarranted and in some cases more females per male would be feasible. Hatchability of fertile eggs was not affected by male to female ratios.
Phenomenology and psychophysics

Recent philosophy of mind has tended to treat “inner” states, including both qualia and intentional states, as “theoretical posits” of either folk or scientific psychology. This article argues that phenomenology in fact plays a very different role in the most mature part of psychology, psychophysics. Methodologically, phenomenology plays a crucial role in obtaining psychophysical results. And more importantly, many psychophysical data are best interpreted as reporting relations between stimuli and phenomenological states, both qualitative and intentional. Three examples are used to argue for this thesis: the Weber–Fechner laws, the Craik-O’Brien–Cornsweet effect, and subjective contour figures. The phenomenological properties that play a role here do so in the role of data that ultimately constrain theoretical work (in this case theory of vision), and not as theoretical posits.
A Computationally Motivated Definition Of Parametric Estimation And Its Applications To The Gaussian Distribution

We introduce a treatment of parametric estimation in which optimality of an estimator is measured in probability rather than in variance (the measure for which the strongest general results are known in statistics). Our motivation is that the quality of an approximation algorithm is measured by the probability that it fails to approximate the desired quantity within a set tolerance. We concentrate on the Gaussian distribution and show that the sample mean is the unique “best” estimator, in probability, for the mean of a Gaussian distribution. We also extend this method to general penalty functions and to multidimensional spherically symmetric Gaussians. The algorithmic significance of studying the Gaussian distribution is established by showing that determining the average matching size in a graph is #P-hard, and moreover approximating it reduces to estimating the mean of a random variable that (under some mild conditions) has a distribution closely approximating a Gaussian. This random variable is (essentially) polynomial time samplable, thereby yielding an FPRAS for the problem.
Context explains divergent effects of anger on risk taking.

The emotion anger is typically associated with increased risk taking. However, anger also produces increased probability estimates that emotionally congruent negative events will occur. This latter finding suggests that the general assumption that anger always increases risky decision making may be subject to caveat. The context of a risk-taking opportunity may dictate whether anger leads to greater or lesser acceptance of risk as a function of which component of the emotional state (i.e., affective or conceptual) is salient. In the experiment reported, participants completed one of two versions of a risk-taking measure that differ according to whether they evoke decisions based on affective feelings or more deliberate reasoning. Results demonstrated that angry participants made riskier decisions than their neutral counterparts under conditions less susceptible to the use of affective information, but made less risky decisions under conditions that favored the use of affective information. The importance of studying emotional states as multifaceted and contextualized phenomenon is discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved). Language: en
Benign Metastasizing Leiomyomata Following Remote Hysterectomy and Oophorectomy

Abstract Background: Benign metastasizing leiomyomata (BML) in the lungs is rarely encountered. It has been reported in patients with leiomyomas after myomectomy or hysterectomy. Case: A woman who ...
Particle size and gas environment effects on blast and overpressure enhancement in aluminized explosives

Abstract Aluminized RDX-based explosives were detonated under controlled conditions while varying particle size and atmosphere in an effort to quantify the contribution of aerobic and anaerobic Al reaction to blast and overpressure. Early time reaction of aluminum acts to enhance the primary explosive blast, and this reaction is approximately half aerobic and half anaerobic (i.e. oxidation by detonation products and/or nitridation), suggesting that very rapid early-time mixing occurs in explosive fireballs. Particle size effects are surprisingly negligible over the range of 3–40 μm, which implies that conventional scaling laws for aluminum combustion provide less insight than previously assumed. Quasi-static pressures obtained in the time period from 5 to 10 microns after detonation suggest that oxidation of aluminum is complete in the presence of 20% oxygen. However, for nitrogen environments, oxidation only proceeds to half its theoretical maximum, except for the smallest (3 μm particles) for which oxidation was nearly complete. These results demonstrate that oxidation of aluminum in aluminized explosives is robust in anaerobic environments, and that simulation efforts cannot neglect anaerobic channels, even though aerobic oxidation provides the greatest energy release.
Transmural contractile reserve after reperfused myocardial infarction in dogs.

OBJECTIVES The goal of this study was to characterize detailed transmural left ventricular (LV) function at rest and during dobutamine stimulation in subendocardial and transmural experimental infarcts. BACKGROUND The relation between segmental LV function and the transmural extent of myocardial necrosis is complex. However, its detailed understanding is crucial for the diagnosis of myocardial viability as assessed by inotropic stimulation. METHODS Short-axis tagged magnetic resonance images were acquired at five to seven levels encompassing the LV from base to apex in seven dogs 2 days after a 90-min closed-chest left anterior descending coronary occlusion, followed by reflow. Myocardial strains were measured transmurally in the entire LV by harmonic phase imaging at rest and 5 ig.kg 21 .min 21 dobutamine. Risk regions were assessed by radioactive microspheres, and the transmural extent of the infarct was assessed by 2,3,5 triphenyltetrazolium chloride staining. RESULTS Circumferential shortening (Ecc), radial thickening (Err) and maximal shortening at rest were greater in segments with subendocardial versus transmural infarcts, both in subepicardium (21.1 6 1.0 vs. 2.5 6 0.6% for Ecc, 20.5 6 1.9 vs. 21.8 6 1.0% for Err, p , 0.05) and subendocardium (22.0 6 1.4 vs. 2.8 6 0.8%, 2.4 6 1.7 vs. 0.0 6 0.9%, respectively, p , 0.05). Under inotropic stimulation, risk regions retained maximal contractile reserve. Recruitable deformation was found in outer layers of subendocardial infarcts (p , 0.01 for Ecc and Err) but also in inner layers (p , 0.01). Conversely, no contractile reserve was observed in segments with transmural infarcts. CONCLUSIONS Under dobutamine challenge, recruitment of myofiber shortening and thickening was observed in inner layers of segments with subendocardial infarcts. These results may have important clinical implications for the detection of myocardial viability. (J Am Coll Cardiol 2000;36:2339 ‐ 46) © 2000 by the American College of Cardiology
Review: diacerein is more effective than placebo and is as effective as NSAIDs for knee and hip osteoarthritis.

Rintelen B, Neumann K, Leeb BF. A meta-analysis of controlled clinical studies with diacerein in the treatment of osteoarthritis. Arch Intern Med 2006;166:1899–906. [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Q In patients with knee or hip osteoarthritis, is diacerein more effective than placebo or other active treatments in reducing pain and improving function? Clinical impact ratings Rheumatology ★★★★★★☆ ### ![Graphic][5] Data sources: PubMed, Medline, EMBASE/Excerpta Medica, Google, Yahoo, AltaVista, arthritis journals, personal files, reference lists, and the drug company. ### ![Graphic][6] Study selection and assessment: randomised controlled trials (RCTs), published or reported in English, French, or German between 1985 and 2004, that compared diacerein with placebo or another active treatment in patients with knee or hip osteoarthritis. 19 RCTs (n = 3058, mean age range 48–67 y, 68% women) met the selection criteria, 16 of which were double blinded. Methodological quality of individual trials was assessed using the Jadad scale. ### ![Graphic][7] Outcomes: pain, function, and use of other medications for pain relief. Outcomes were assessed at 2 time points: at the end of active treatment (duration 1–36 mo, median 3 … [1]: {openurl}?query=rft.jtitle%253DArchives%2Bof%2BInternal%2BMedicine%26rft.stitle%253DArch%2BIntern%2BMed%26rft.issn%253D0003-9926%26rft.aulast%253DRintelen%26rft.auinit1%253DB.%26rft.volume%253D166%26rft.issue%253D17%26rft.spage%253D1899%26rft.epage%253D1906%26rft.atitle%253DA%2BMeta-analysis%2Bof%2BControlled%2BClinical%2BStudies%2BWith%2BDiacerein%2Bin%2Bthe%2BTreatment%2Bof%2BOsteoarthritis.%26rft_id%253Dinfo%253Adoi%252F10.1001%252Farchinte.166.17.1899%26rft_id%253Dinfo%253Apmid%252F17000948%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1001/archinte.166.17.1899&link_type=DOI [3]: /lookup/external-ref?access_num=17000948&link_type=MED&atom=%2Febmed%2F12%2F3%2F74.atom [4]: /lookup/external-ref?access_num=000240730500016&link_type=ISI [5]: /embed/inline-graphic-1.gif [6]: /embed/inline-graphic-2.gif [7]: /embed/inline-graphic-3.gif
Defective cellular immune response in vitro in common variable immunodeficiency

Mononuclear cells from 39 patients with hypogammaglobulinemia of the common variable type were analyzed forin vitro proliferative responses to a panel of cell activators in order to examine the lymphocyte response to mitogens and to study the capacity to generate an immunologically specific secondary response. Patient lymphocyte response to phytohemagglutinin and concanavalin A was found to be significantly lower than that of controls studied in parallel (P<0.01), and low response did not correlate with T-lymphocyte number. Response to pokeweed mitogen was significantly lower than that of controls (P<0.01), but response to zinc, tested in a few patients, was normal. Strong depressions of patient lymphocyte proliferative responses toCandida albicans, Escherichia coli, andStaphylococcus aureus were observed (P<0.01); all of these microbial activators require intact B-cell function for maximum response. Repeated testing of individual patients indicated that poor lymphocyte response could be consistently observed. Examination of changes inin vitro lymphocyte response during clinical course and disease management showed that a consistent pattern of intrinsic lymphocyte functional deficiency could be demonstrated.
Quantum interference noise near the Dirac point in graphene

Effects of disorder on the electronic transport properties of graphene are strongly affected by the Dirac nature of the charge carriers in graphene. This is particularly pronounced near the Dirac point, where relativistic charge carriers cannot efficiently screen the impurity potential. We have studied time-dependent quantum conductance fluctuations in graphene in the close vicinity of the Dirac point at low temperatures. We show that the low-frequency noise arises from the quantum interference effects due to scattering on slowly fluctuating impurities. An unusually large reduction of the noise power in magnetic field suggests that an additional symmetry plays an important role in this regime.
Isolation and characterization of a serine esterase from cytolytic T cell granules

Cytotoxic T lymphocytes and lymphocytes with NK-like activity contain a serine esterase activity which has been localized to their cytoplasmic granules by cytochemistry and subcellular fractionation studies. The serine esterase-specific inhibitor 3H-DFP labels two protein species in the granules. The two proteins, referred to as serine esterases 1 and 2 (SE 1 and SE 2), migrate with Mr of 34-36 kd and 28-30 kd, respectively, under reducing conditions. SE 1 shows trypsin-like activity and has been purified to apparent homogeneity. Under nonreducing conditions, SE 1 has an Mr of 60-66 kd, suggesting that it may consist of two disulfide-linked subunits of 34-36 kd each. SE 1 cleaves fibrin and casein, has a pl greater than 10, and optimal activity at pH 8. The substrate specificity of SE 2 is not known. The serine esterase activity is secreted by lymphocytes that have been stimulated with the calcium ionophore A23187. The serine esterases described here could play an active role in cell-mediated killing.
The role of carotenoids on the risk of lung cancer.

Smoking prevention and cessation remain the primary methods of reducing the incidence of lung cancer. The limited success of efforts towards smoking cessation have led to increasing interest in the role of nutrition in lung cancer prevention. One class of nutrients that has attracted attention as potential chemopreventive agents is the carotenoids, especially beta-carotene, due to their antioxidant properties. In vitro, carotenoids exert antioxidant functions and inhibit carcinogen-induced neoplastic transformation, inhibit plasma membrane lipid oxidation, and cause upregulated expression of connexin 43. These in vitro results suggest that carotenoids have intrinsic cancer chemopreventive action in humans. Many cohort and case-control study data have shown an inverse relationship between fruit and vegetable consumption and lung cancer, although several more recent studies have cast doubt on these findings. Different effects of various dietary nutrients on lung cancer risk have been observed. Several prospective intervention trials were undertaken to examine the effect of supplementation on the risk of lung cancer. Some of these studies demonstrated an increased incidence and mortality from lung cancer in those receiving supplementation. Many hypotheses have emerged as to the reasons for these findings. Semin Oncol 30:86-93. Copyright 2003, Elsevier Science (USA). All rights reserved.
Calbindin immunoreactivity in the geniculo-extrastriate system of the macaque: implications for heterogeneity in the koniocellular pathway and recovery from cortical damage.

Although most projection neurons in the primate dorsal lateral geniculate nucleus (dLGN) target striate cortex (V1), a small number project instead to extrastriate visual areas and have been suggested to play a role in the preserved vision ("blindsight") that survives damage to V1. Moreover, the distribution of dLGN cells projecting to extrastriate bears a striking similarity to that of neurons that stain for calbindin D-28K (Cal), a calcium-binding protein involved in regulating neuronal excitability and considered a marker for the koniocellular or "K" pathway of geniculocortical processing. In these studies, we used double-labeling techniques to examine whether Cal content characterizes all or a subset of neurons making up the geniculo-extrastriate pathway in normal macaque monkeys. After injections of cholera toxin B-subunit into the prelunate gyrus, the proportion of retrogradely labeled neurons in the dLGN that were also immunoreactive for Cal varied from less than 40% to over 80%, indicating that only a subset of the geniculo-extrastriate projection falls within the K pathway as defined by Cal content. Analysis of the injected territories indicated that identity of the extrastriate cortical target may be systematically related to Cal content in the geniculo-extrastriate projection. To see whether the Cal-immunoreactive dLGN population might potentially play a role in preserved vision after V1 damage, we also examined the dLGN of a macaque that had sustained a lesion of V1 in infancy and survived until 4 years. In this animal, large, intensely Cal-immunoreactive neurons were found scattered throughout the otherwise degenerated dLGN zones and made up over 95% of the identifiable remaining neurons. The results support an emerging view that the macaque koniocellular system is highly heterogeneous in nature and also suggest that Cal content may be a critical feature of the pathway by which visual information reaches extrastriate cortex in the absence of V1.
The thermodynamics of synergistic extraction of bismuth by 2-ethylhexyl phenylphosphonic acid and micelles of dinonyl naphthalene sulfonic acid

Abstract Synergism using the title metal extracting agents has been observed for bismuth. Thermodynamic parameters of the extraction process were determined by the temperature coefficient of extractability. The extraction of bismuth from HClO 4 by dinonyl naphthalene sulfonic acid (HDNNS) and the mixed ligand system are entropy controlled, whereas the process is enthalpy controlled when 2-ethylhexyl phenylphosphonic acid (HEHΦP) is the extractant. These results shed further light on the mechanism of the synergy by the combined extractants.
Imaging Mass Spectrometry: A New Tool for Pathology in a Molecular Age

Mass spectrometry (MS) provides unique advantages for the analysis of clinical specimens, and these capabilities have been critical to the advancement of diagnostic medicine. To date, LC-MS is the MS platform most commonly used for diagnostics; however, LC-MS based proteomics is very labor intensive and costly to implement for high volume assays. Furthermore, when analyzing tissue samples, additional laborious sample preparation steps must be employed (e.g. extraction methods or laser microdissection). The direct analysis of cells and tissues by MALDI imaging MS has developed significant momentum for applications that have diagnostic potential. MALDI imaging MS provides molecular information from specific cell types within tissue sections; however, this laser-based approach significantly reduces the analysis time for each location sampled. This Viewpoint discusses the technologies for direct analysis of tissues, the potential for diagnostic applications using MALDI imaging MS, and the challenges faced in the transfer of the technology to the clinical laboratory.
Frequent hypoglycemic episodes in the treatment of patients with diabetic ketoacidosis.

Background.— Previous studies of the management of Background.—Previous abetic ketoacidosis have noted a wide range of incidence of hypoglycemia but have not studied the risk factors associated with it. Methods.— To describe the incidence of hypoglycemia in patients hospitalized with diabetic ketoacidosis, we retrospectively reviewed the charts of all adult patients with the diagnosis of diabetic ketoacidosis at three private, community hospitals in Milwaukee, Wis, between January 1, 1987, and May 31, 1990. Two hundred twenty admissions in 150 patients met our inclusion criteria. Results.— In 30% (66/220) of cases of diabetic ketoacidosis, a serum glucose level or Accu-Chek (BoehringerMannheim, Indianapolis, Ind) finding was 2.7 mmol/L or less during the first 14 days of hospitalization. No factors could be identified that were associated with a significantly increased risk of early hypoglycemia (within the first 48 hours of admission). The risk of a "late" occurrence of hypoglycemia (after 48 hours of hospitalization) was increased by fever (relative risk, 2.05; 95% confidence interval [CI], 1.16 to 3.63), "nothing orally" status (relative risk, 3.01; 95% CI, 1.88 to 4.83), hepatic disease (relative risk, 2.56; 95% CI, 1.39 to 4.70), and renal disease (relative risk, 2.07; 95% CI, 1.26 to 3.39). A logistic regression analysis showed "nothing orally" status to be associated with an increased risk of any hypoglycemia occurring during the hospitalization (relative risk, 2.39; 95% CI, 1.63 to 3.51). Physicians and nurses documented the first episode of hypoglycemia in their notes 45.5% and 80.3% of the time, respectively. Conclusion. Hypoglycemia is still a common complication of diabetic ketoacidosis, is associated with hepatic and renal disease as well as fever and "nothing orally" status, and is not documented well in physician notes. (Arch Intern Med. 1992;152:2472-2477)
Energy efficiency advocacy groups Factors affecting their influence on DSM and IRP

Abstract Under which conditions are energy efficiency advocacy efforts most effective? In this article, we assess the activities of selected US energy efficiency advocacy groups (EEAGs) in their attempts to influence investor-owned electric utilities and their regulators. Our assessment is based upon a two-year project completed in late 1993 involving 10 in-depth case studies. The case studies focused on interactive efforts between utilities and non-utility parties but examined other, related EEAG efforts as well. The article concludes with a summary of key findings resulting from the project.
Reactive-power control of photovoltaic inverters for mitigation of short-term distribution-system voltage variability

The output power variability of intermittent renewable sources can cause significant fluctuations in distribution system voltages. A local linear controller that exploits the capability of a photovoltaic inverter to provide both real and reactive power is described. This controller substitutes reactive power for real power when fluctuations in the output of the photovoltaic source are experienced. In this way, the inverter can help mitigate distribution system voltage fluctuations. The local linear controller has a control parameter called the substitution rate, and several methods of calculating this control parameter are described, including sensitivity minimization and violation optimization methods, which can be applied on a local or global basis and on a per-phase or phase-average basis. This controller is examined using an example distribution system, and it is found that the controller is effective at mitigating voltage violations. Furthermore, comparisons between the alternative methods of selecting the substitution rate are performed.
Design and fabrication of L5 photonic band gap nanocavities for stimulated raman amplification in monolithic silicon

The concept, design and fabrication of L5 photonic crystal nanocavities for stimulated Raman amplification in monolithic silicon is suggested for the first time. Specific ultrahigh Q/Vm nanocavities are presented towards significant on-chip silicon Raman amplification
A Low-Power Compressive Sampling Time-Based Analog-to-Digital Converter

This paper presents a low-power, time-based, compressive sampling architecture for analog-to-digital conversion. A random pulse-position-modulation (PPM) analog-to-digital conversion (ADC) architecture is proposed. A prototype 9-bit random PPM ADC incorporating a pseudo-random sampling scheme is implemented as proof of concept. This approach leverages the energy efficiency of time-based processing. The use of sampling techniques that exploit signal compressibility leads to further improvements in efficiency. The random PPM (pulse-position-modulation) ADC employs compressive sampling techniques to efficiently sample at sub-Nyquist rates. The sub-sampled signal is recovered using a reconstruction algorithm, which is tailored for practical hardware implementation. We develop a theoretical analysis of the hardware architecture and the reconstruction algorithm. Measurements of a prototype random PPM ADC and simulation, demonstrate this theory. The prototype successfully demonstrates a 90% reduction in sampling rate compared to the Nyquist rate for input signals that are 3% sparse in frequency domain.
Integration of Heat Assisted Magnetic Recording technology into enterprise hard disk drives

Hard disk drive areal density growth has reduced the cost of data storage to pennies per gigabyte, but the super-paramagnetic limit is a looming potential impediment to the continuation of this growth. In order to overcome this obstacle, Heat Assisted Magnetic Recording (HAMR) technology is being developed as a successor to conventional perpendicular magnetic recording. HAMR overcomes the super-paramagnetic limit by temporarily heating the media during the recording process. Heating the media magnetically “softens” it for recording, enabling the fields available from current generation writers to record data. As the media rotates away from the recording head, it quickly cools down to room temperature. This allows for the usage of high anisotropy materials in the recording layer, which are very stable at typical storage temperatures, enabling long-term data retention.
Acoustic Target Reconstruction Using Geometrical Optics Phase Information

Abstract : In this note a simple algorithm, which uses the phase information from the geometrical optics limit, to construct the shape of an object is presented. Essentially, the phase in the back scattered direction determines the equation of the tangent plane at the unique, but unknown, specular point. This plane depends upon the two spherical angles theta and phi which describe the incident wave direction. The observation that the tangent plane envelopes the obstacle as theta and phi are varied, allows the derivation of an explicit formula for the equation of the surface in terms of the measured scattered phase. An analogous two-dimensional formula is also presented.
38-year-old woman with abnormal liver enzymes and hyperlipidemia.

A 38-year-old woman presented to our clinic for evaluation of a 1.5-year history of abnormal liver test results. She was asymptomatic except for intermittent fatigue. A complete review of systems yielded no relevant findings.
An electrochemical investigation of TMJ implant metal alloys in an artificial joint fluid environment: The influence of pH variation

Abstract Objective To investigate the corrosion behaviour of commonly used TMJ implants alloys (CoCrMo and Ti6Al4V) under simulated physiological conditions. Methods Corrosion behaviour was evaluated using standard electrochemical corrosion techniques and galvanic corrosion techniques as per ASTM standards. Standard electrochemical tests ( E corr , I corr , R p and C f ) were conducted in bovine calf serum (BCS), as a function of alloys type and different pHs. Galvanic corrosion tests were conducted in BCS at a pH of 7.6. Alloy surfaces were characterized using white-light interferometry (WLI) and scanning electron microscopy (SEM). Results The potentiodynamic test results exhibited the enhanced passive layer growth and a better corrosion resistance of Ti6Al4V compared to CoCrMo. Electrochemical impedance spectroscopy measurements demonstrated the influence of protein as a function of pH on corrosion mechanisms/kinetics. Galvanic coupling was not a major contributor to corrosion. SEM and WLI images demonstrated a significantly higher in surface roughness in CoCrMo after corrosion. Conclusions The results of this study suggest that Ti6Al4V shows superior corrosion behaviour to CoCrMo due to its strong passive layer, simulated joint fluid components can affect the electrochemical nature of the metal/electrolyte interface as a function of pH, and the galvanic effect of coupling CoCrMo and Ti6Al4V in a single joint is weak.
The TOR Complex 1 Is Distributed in Endosomes and in Retrograde Vesicles That Form from the Vacuole Membrane and Plays an Important Role in the Vacuole Import and Degradation Pathway

The key gluconeogenic enzyme fructose-1,6-bisphosphatase (FBPase) is induced when Saccharomyces cerevisiae are starved of glucose. However, when glucose is added to cells that have been starved for 3 days, FBPase is degraded in the vacuole. FBPase is first imported to Vid (vacuole import and degradation) vesicles, and these vesicles then merge with the endocytic pathway. In this report we show that two additional gluconeogenic enzymes, isocitrate lyase and phosphoenolpyruvate carboxykinase, were also degraded in the vacuole via the Vid pathway. These new cargo proteins and FBPase interacted with the TORC1 complex during glucose starvation. However, Tor1p was dissociated from FBPase after the addition of glucose. FBPase degradation was inhibited in cells overexpressing TOR1, suggesting that excessive Tor1p is inhibitory. Both Tco89p and Tor1p were found in endosomes coming from the plasma membrane as well as in retrograde vesicles forming from the vacuole membrane. When TORC1 was inactivated by rapamycin, FBPase degradation was inhibited. We suggest that TORC1 interacts with multiple cargo proteins destined for the Vid pathway and plays an important role in the degradation of FBPase in the vacuole.
Synergistic anti-tumor effect of glycosylphosphatidylinositol-anchored IL-2 and IL-12.

Background Preclinical and clinical studies have demonstrated that interleukin 2 (IL-2), interleukin 12 (IL-12), and some other cytokines, play important roles in activating host immune responses against tumor growth. However, severe side effects caused by systemic high-dose administration of these cytokines limit their clinical application. In our previous study, local high doses of IL-2 were achieved by a GPI-anchoring technology; therefore, it will be interesting to know if this technology works for other cytokines. Methods A fusion gene containing murine IL-12 and the glycosylphosphatidylinositol (GPI) anchor signal sequence was generated and transfected into the murine melanoma tumor cell line B16F0 either alone or together with a vector encoding GPI-anchored IL-2. The GPI-anchored cytokine expression of the selected stable clones was assayed in vitro by ELISA and their anti-tumor effects were analyzed in vivo by tumor lymphocyte infiltration and tumor growth studies. Results GPI-anchored IL-12 was successfully expressed on the cell surface as indicated by FACS analysis and IL-12 ELISA assay. The GPI-anchored IL-12 enhanced lymphocyte infiltration and significantly inhibited tumor growth. More importantly, when GPI-anchored IL-12 and GPI-anchored IL-2 were co-delivered, a synergistic anti-tumor effect was observed in both subcutaneous and intravenous tumor models. Conclusions GPI anchorage of cytokines represents a new approach to locally deliver high doses of cytokines without the severe adverse effects normally accompanied with systematic high-dose administration of these cytokines. Copyright © 2004 John Wiley & Sons, Ltd.
Occurrence of C10−C13 Polychlorinated n-Alkanes in Canadian Midlatitude and Arctic Lake Sediments

Sediment cores from six lakes in Canada ranging from 49°N to 81°N were analyzed for C10−C13 polychlorinated n-alkanes (PCAs) with the intent of (i) examining the depositional trends with increasing latitude, (ii) studying the historical profiles and fluxes of PCAs in dated sediment slices, and (iii) investigating possible in situ degradation. Sediment slices were dated using 210Pb and 137Cs, and extracts were analyzed for PCA concentrations by high resolution gas chromatography electron capture negative ion high resolution mass spectrometry (HRGC-ECNI/HRMS) in the selected ion monitoring (SIM) mode. Concentrations of total PCAs in surface sediments declined significantly from 135 ng/g (dry weight (dw)) in sediments from the southern basin of Lake Winnipeg (50°N/96°W, Manitoba) to 4.52 ng/g in Hazen Lake (81°N/71°W, high Arctic); corresponding surficial fluxes were 147 and 0.9 μg/m2 yr, respectively. The high flux of PCAs to the south Lake Winnipeg basin suggests local contamination. This was confirmed by ...
INNOVATIVE APPLICATIONS OF IONIC LIQUIDS AS “GREEN” ENGINEERING LIQUIDS

Over the past decade, ionic liquids (ILs) have become one of the fastest growing “green” media for chemists and engineers due to their superb physicochemical properties. The applications of these remarkable salts in reactions and extraction processes have been extensively investigated and reviewed. This review, however, highlights recent advances of ILs as versatile “green” engineering liquids in a variety of industrial applications including heat transfer fluids, azeotrope-breaking liquids, lubricants, electrolytes, liquid crystals, supported IL membranes, plasticizers, and more. This review is not intended to be comprehensive, but rather to discuss the potentials of ILs for diverse industrial applications.
Ethylene production and ethylene effects on respiration rate of postharvest sugarbeet roots

Abstract Ethylene elevates respiration, is induced by wounding, and contributes to wound-induced respiration in most postharvest plant products. Ethylene production and its effects on respiration rate, however, have not been determined during storage of sugarbeet ( Beta vulgaris L.) root, even though any elevation in respiration due to ethylene would increase storage losses and reduce postharvest quality. To determine the effect of ethylene on sugarbeet root storage respiration rate, sugarbeet root ethylene production was quantified, and the effects of exogenous ethylene, an ethylene biosynthesis inhibitor, and ethylene response inhibitors on root respiration rate were determined using uninjured, severely injured, and conventionally harvested roots. Ethylene production was low (0.045–0.047 pmol kg −1 s −1 ) in uninjured and conventionally harvested and piled roots. Consequently, ethylene concentrations in commercial piles 0–67 d after piling were low, ranging from −1 . Exogenous ethylene at concentrations of 0.020–14 μL L −1 increased root respiration. The increase in respiration rate, however, was transient at ethylene concentrations ≤0.11 μL L −1 suggesting that any ethylene effects on respiration rate in commercial piles would be short term. Severe injury induced ethylene production an average of 3.7-fold and increased respiration rate 3–4 d after injury. Wound-induced ethylene production, however, was not directly responsible for wound-induced respiration since elimination of wound-induced ethylene production by the ethylene synthesis inhibitor aminoethoxyvinylglycine had no effect on wound-induced respiration. The ethylene response inhibitors 1-methylcyclopropene (1-MCP) and silver thiosulfate reduced wound-induced respiration 3–4 d after injury when applied after wounding. A portion of the increase in respiration due to wounding, therefore, required ethylene perception. However, when applied prior to wounding, 1-MCP elevated wound-induced respiration 3–4 d after injury, suggesting that blockage of ethylene receptors prior to injury was ineffective at eliminating ethylene perception after wounding, possibly due to the synthesis of new receptors after the injury. Moreover, 1-MCP effects on root respiration rate occurred only when roots were severely injured; 1-MCP had no effect on respiration rate of uninjured or conventionally harvested roots. Postharvest sugarbeet roots, therefore, produce ethylene, increase ethylene production in response to wounding, and respond to exogenous ethylene with an increase in respiration rate, but ethylene production and ethylene effects on root respiration rate are likely to be small under commercial storage conditions and of limited economic significance.
Evaluation of an Eyes-Free Cursorless Numeric Entry System for Wearable Computers

We report on the results of a user study to investigate the utility of passive haptics for eyes-free numeric entry. This work targets cursorless user interfaces designed for use with a watch-sized wrist-worn computer. Our study compared three approaches for selecting one of a set of eight numeric parameters and entering its value, both with and without visual feedback. The three selection methods utilized physical buttons alone, buttons with a touch-sensor utilizing passive haptics, and the touch sensor with passive haptics alone. The results show that passive haptics allowed users to perform parameter selection and number entry tasks, with statistically insignificant differences in accuracy and speed when used with and without visual feedback. Furthermore, there was no statistically significant difference in accuracy and speed between the button-based methods and the purely touch-sensor?based approaches.
Optimum Allocation of Stratified Random Samples Designed for Multiple Mean Estimates and Multiple Observed Variables

Abstract With a fixed overall sampling cost, it is essential to achieve minimal error variance of the estimated population statistics in order to be maximally efficient. The error variance of a population mean estimate derived from a stratified random sample (StRS) may be minimized by determining the optimum allocation of observations to the strata. A variety of approaches currently exists to achieve this. Moreover, for obvious economic reasons, a survey's objective is generally more than the estimation of a single population mean of a single variable. That is, mean values restricted to various subsets of strata and mean values belonging to several observed variables are simultaneously estimated. Available optimization procedures, however, only partially address this issue. In this paper, a method for optimum allocation is developed that explicitly allows the consideration of any number of observed variables and any number of mean estimates (as defined by the respective subsets of relevant strata). The pr...
Volatile Constituents of Grass and Corn Silage. II. Gas-entrained Aroma

Summary The volatiles entrained from several grass and corn silages and condensed in cold traps were analyzed by gas-liquid chromatography. The volatiles from the grass silages were found to be mixtures of methylsulfide, ethanal, propanal, acetone, butanone, methanol, ethanol, propanol, 2-butanol, methyl acetate, and the ethyl and propyl esters of formic, acetic, propionic, and butyric acids. While methylsulfide, ethanal, methanol, ethanol, methyl acetate, ethyl formate, and ethyl acetate were commonly detected in the corn silage volatiles, propanal, acetone, butanone, propanol, 2-butanol and other esters were not consistently detected, and the butyrates were usually absent. Rapid transmission of some or all of these compounds to the mammary gland via the respiratory system is believed to be responsible in part for the development of feed flavor in milk from cows fed silage.
Cosmology with a long range repulsive force

We consider a class of cosmological models in which the universe is filled with a (non-electric) charge density that repels itself by means of a force carried by a vector boson with a tiny mass. When the vector's mass depends upon other fields, the repulsive interaction gives rise to an electromagnetic barrier which prevents these fields from driving the mass to zero. This can modify the cosmology dramatically. We present a very simple realization of this idea in which the vector's mass arises from a scalar field. The electromagnetic barrier prevents this field from rolling down its potential and thereby leads to accelerated expansion.
Streptozotocin-induced diabetes produces a naltrexone-reversible lowering of self-stimulation threshold

Stimulation frequency thresholds for lateral hypothalamic self-stimulation were monitored for 3 weeks following the induction of diabetes with streptozotocin (STZ). In each of the 3 weeks following STZ treatment, thresholds of diabetic rats were significantly lower than their pre-STZ baseline while thresholds of control animals did not change. Naltrexone (5.0 mg/kg, s.c.) increased thresholds of diabetic rats while having no effect on thresholds of control rats. These results suggest that STZ-induced diabetes is associated with an opioid-mediated lowering of self-stimulation threshold. The possible relationship between this finding and similar findings obtained in food-restricted animals is discussed.
Analysis Of A Noisy Phase-Only Matched Filter Under Partially Coherent Illumination

It has been shown that phase-only matched filtering can provide 100% optical efficiency in an optical correlator while at the same time producing a very well defined correlation spot. This analysis has been carried forward and applied to the case of a broad spectral band or white-light optical correlator. The optical correlator under white-light illumination operates at a multiplicity of wavelengths which favorably affect the noise performance of the system. Computer simulations have been used to study the noise suppression qualities of the correlator when noise is present at the filter plane. The result indicates that the noise level at the correlation plane can be reduced by utilizing a higher number of spectral band filters. It is shown that the output signal-to-noise ratio (SNR) improves approximately as the square root of N where N is the number of spectral bands employed in the phase-only matched filter. The coherence requirements for phase-only matched filtering under broadband illumination is studied. The effect of partially coherent illumination on the correlation bandwidth is determined.
Time boxing planning: buffered moscow rules

Time boxing is a management technique which prioritizes schedule over deliverables but time boxes which are merely a self, or an outside, imposed target without agreed partial outcomes and justified certainty are at best, an expression of good will on the part of the team. This essay proposes the use of a modified set of Moscow rules which accomplish the objectives of prioritizing deliverables and providing a degree of assurance as a function of the uncertainty of the underlying estimates.
Hedgehog regulates angiogenesis of intersegmental vessels through the VEGF signaling pathway.

Background: The cellular mechanisms regulating branching and growth of the intersegmental vessels (ISVs) are not well understood. We have carried out studies demonstrating that Hedgehog (Hh) signaling is a major regulator of intersomitic vessel growth. Results: Inhibition of Hh activity by cyclopamine completely blocks formation of intersomitic vessels in the avian embryo. Examination of gene expression patterns in Hh-deficient embryos shows that components of the VEGF and Notch signaling pathways are down-regulated. However, we find no evidence that Notch signaling plays a significant role in regulation of intersomitic vessel growth. Indeed, it appears that Hh modulation of Vascular Endothelial Growth Factor, VEGF, is the primary regulator of growth of intersomitic vessels in the avian embryo. Conclusions: Inhibition of the VEGF pathway results in absence of ISVs, whereas stimulation of VEGF expression leads to precocious branching of ISVs. These results demonstrate that Hh is an essential modulator of VEGF expression during developmental angiogenesis. Developmental Dynamics 241:1034–1042, 2012. © 2012 Wiley Periodicals, Inc.
How to Analyze Survey Data Pertaining to the Time Bind, and How Not to Analyze Such Data

This note considers various ways of analyzing survey data pertaining to a central thesis of The Time Bind (Hochschild, 1997), and it comments on the particular analysis presented by Brown and Booth (2002). The following kinds of problems will be discussed here: (1) problems pertaining to the measurement of concepts, (2) problems pertaining to the selection of the data to be analyzed, and (3) problems pertaining to the selection of the statistical models to be used in the analysis. Appropriate methods for dealing with each of these three kinds of problems are introduced and described in the present note. When these appropriate methods are compared with the particular methods applied by Brown and Booth (2002), we find fault with the latter methods. Our attention in this note is focused on the analysis of data pertaining to a central thesis of The Time Bind, but the general approach presented here can also be applied more generally to study other theses of interest in the social sciences.
hp submeshing via non-conforming finite element methods

Abstract Non-conformity in the hp version can involve incompatibility in both the degrees and the meshes between adjoining subdomains. In this paper, we show how the mortar finite element method M0 and two new variants M1, M2 can be used to join together such incompatible hp sub-discretizations. Our results show optimality of the resulting non-conforming method for various h , p and hp discretizations, including the case of exponential hp convergence over geometric meshes. We also present numerical results for the Lagrange multiplier when the method is implemented via a mixed method. Three-dimensional considerations suggest that our methods M1, M2 are easier to generalize to arbitrary meshes than M0.