cssi/SciSciGPT-SciSciNet huggingface dataset:
MATLAB® Essentials: A First Course for Engineers and Scientists

All disciplines of science and engineering use numerical methods for complex problem analysis, due to the highly mathematical nature of the field. Analytical methods alone are unable to solve many complex problems engineering students and professionals confront. Introduction to MATLAB® Programming for Engineers and Scientists examines the basic elements of code writing, and describes MATLAB® methods for solving common engineering problems and applications across the range of engineering disciplines. The text uses a class-tested learning approach and accessible two-color page design to guide students from basic programming to the skills needed for future coursework and engineering practice.
Take me out to the ballgame: The acoustics of the softball bat piano

As a multimedia supplement for a recent article “Acoustics and Vibration of Baseball and Softball Bats” [Acoustics Today , 13(4), 35–42 (2017)] the author created a “softball bat piano” and played the tune “Take Me Out to the Ballgame.” The bat piano is a collection of softball bats, clamped at the handles, selected for their barrel frequencies. It is played by striking the bat barrels with a softball. The structural modes of the hollow cylindrical barrel of an aluminum or composite bat are responsible for the trampoline effect which affects the performance of the bat as it is used for the game of softball. However, the “hoop mode” which gives rise to the trampoline effect is also the source of the bat piano’s audible musical sound. The nature of these cylindrical shell vibrations will be discussed, highlighting similarities to the musical properties of bells and chimes. The influence of bat construction and materials on the “hoop frequency” will be explained, along with the process of selecting bats with a range of frequencies wide enough to form a musical scale. If time permits, video of additional musical selections will be shown.
An Integrated Knowledge Graph to Automate GDPR and PCI DSS Compliance

Big data analytics related to consumer behavior, market analysis, opinions, and recommendation often deal with end user's derived and inferred data, along with the observed data. To ensure consumer data protection, rules defined by the European Union’s General Data Protection Regulation (EU GDPR) must be adhered to by every organization using Personally Identifiable Information (PII) data for Big Data analysis. Similarly, Payment Card Industry Data Security Standard (PCI DSS) has policy guidelines specifically for organizations handling consumer’s payment card data. Both data regulation policies are currently available only in textual format and require significant manual effort to ensure their compliance. We have developed an integrated, semantically rich Knowledge Graph (or Ontology) to represent the rules mandated by both PCI DSS and EU GDPR. In the Ontology, we have also identified the obligations defined in these regulations and related them with corresponding Cloud Security Alliance (CSA) controls. We have validated this Knowledge Graph against the data policies of major vendors that deal with Big Data. This Knowledge Graph that is available in the public domain can be used by Big Data practitioners to automate data protection compliance in their organization.
Two-Way Slabs

Prestressed concrete slabs are used in buildings, parking garages, roofs, decks, and other similar applications. They may be either one-way slabs, spanning in predominately one direction, or two-way slabs, spanning in two orthogonal directions. One-way slabs are discussed in Example 6.2 and in Chap. 9. Two-way slabs are most efficient when the column spacing in each direction is approximately the same. Aspect ratios greater than 2:1 generate predominately one-way action and are designed as one-way slabs with attention paid to localized bending at the corners. Two-way slab systems are typically more efficient and therefore more slender structures. As such, punching shear can control the slab thickness. Design typically assumes that the slab is subjected to a uniformly distributed area loading. Slabs subjected to concentrated loadings require additional attention during the analysis and design.
High-performance, cost-effective 2z nm two-deck cross-point memory integrated by self-align scheme for 128 Gb SCM

We demonstrate a high-performance and cost-effective cross-point memory (CPM) technology for two-deck 128 Gb storage class memory (SCM). The unit MAT size is 16 Mb consisting of a 2z nm 1S1M (one selector one memory) structure that is patterned by only two ArF-i steps per deck for a low cost per bit. The formidable task of self-align etch is enabled by the use of state-of-the-art etching and integration technology, which otherwise easily leads to hard fail or poor cell characteristics and reliabilities. New phase change materials (N-PCMs) are developed to have a large V t window and a uniform V t distribution for a sufficient read window margin (RWM) and a corresponding low raw bit error rate (RBER). New chalcogenide selectors (NCSs) are also developed to provide low V t instability and very low leakage current. The new CPM is able to provide a sufficient RWM for 16 Mb MATs with very low latencies of write (set ≤ 300 ns) and read (≤ 100 ns). We also demonstrate its decent write disturbance and high reliabilities such as endurance and thermal retention.
The Use of Text Message Reminders to Increase Completion of Web-Based Surveys: Results of Two Randomized Control Trials

Limited research examines the use of text messaging to improve survey response rates. Drawing on Tailored Panel Management, the Florida Study of Professionals for Safe Families utilized text messag...
Preferences for fairness over losses

Abstract Economic decision making often involves determining how to share losses, or liabilities. While preferences for fairness over positive outcomes, i.e., gains, have been extensively studied, preferences for fairness over negative outcomes, i.e., losses, are largely unknown. Preferences for fairness over losses may differ from those over gains, given loss aversion and disutility from imposing losses on others (e.g., the do-no-harm principle). In two incentivized dictator game experiments, we examine altruism in two different frames – a loss condition and a gain condition. Study 1 shows that Dictators are more generous when splitting losses compared to gains. Study 2 shows that Dictator generosity in the loss condition substantially decreases when subjects are reminded of the payoff distribution resulting from their decisions. Our results support the idea that preferences for fairness over losses may differ from those over gains, underscoring the importance of studying preferences for fairness over losses and their determinants.
Chapter 2 – TABULAR ANALYSIS

Publisher Summary This chapter focuses on tabular analysis, which involves displaying the data in a logical, consistent format that permits easy and accurate interpretation. It presents a few basic rules used for constructing tables, which include specifying the independent and dependent variables, dividing the data into categories of the independent variable, and describing each of the categories in terms of the dependent variable values. The chapter also presents a few conventions used for tabular analysis, which include making the independent variable as rows, making the dependent variables as columns, and giving the table a title that is both descriptive and easily remembered. Before constructing a table, the nature of the data must be understood, the independent and dependent variables determined, and the categorization of the data decided upon.
Curie temperature modeling of magnetocaloric lanthanum manganites using Gaussian process regression

Abstract Efficient solid-state refrigeration techniques have drawn increasing attention due to their potential for improving energy efficiency of refrigeration, air-conditioning, and temperature-control systems without using harmful gas as in conventional gas compression techniques. Research on magnetocaloric lanthanum manganites with near-room-temperature Curie temperature, T C , shows promising results for further developments of magnetic refrigeration devices. By incorporating chemical substitutions, oxygen content modifications, and various synthesis methods, these manganites experience lattice distortions from perovskite cubic structures to pseudocubic, orthorhombic, and rhombohedral structures. Further changes in lattice parameters can also be achieved by the introduction of strain due to lattice mismatches, where T C can be tuned more effectively. Empirical results and previous models through thermodynamics and first-principles have shown that changes in lattice parameters correlate with those in T C , but correlations are merely general tendencies and obviously not universal. In this work, the Gaussian process regression model is developed to find statistical correlations between T C and lattice parameters among lanthanum manganites. Nearly 100 lattices, cubic, pseudocubic, orthorhombic, and rhombohedral, with T C ranging from 40 K to 375 K are explored for this purpose. The modeling approach demonstrates a high degree of accuracy and stability, contributing to efficient and low-cost estimations of T C , providing guidance on thin film structure design and helping understandings of magnetic phase transformations and magnetocaloric effects in lanthanum manganites.
Incorporating Ethics Content Throughout an Integrated Pharmacy Curriculum.

Objective. To describe how Ethics content, formerly taught as a third-year stand-alone course, was incorporated into nine didactic courses across all three years, and into IPPEs and APPEs in a newly-integrated, two-campus PharmD curriculum at the University of Minnesota. Curriculum changes were intended to (1) provide students with opportunities to discuss and apply Ethics concepts several times throughout the curriculum, and (2) highlight Ethics topics relevant to material students were learning in the host course at the time. Methods. The free-standing one-credit required Ethics course from the old curriculum was eliminated. Partnering with Course Directors from nine required courses across all three years of the didactic curriculum and with the Office of Experiential Education, an Integrated Ethics syllabus was created that provided each class of approximately 170 students with at least one credit of didactic Ethics instruction and added Ethics activities to the experiential curriculum. Learning approaches include lecture, case analysis and discussions with preceptors. Assessment approaches include written case analysis, multiple-choice and true/false questions, case vignette-based short-answer essay questions, and student discussions with preceptors. Results. Students consistently rate the Ethics sessions as useful, but some students find repeated application of the ethics problem-solving framework tedious and repetitive. Conclusion. It is possible to embed Ethics topics within different courses as part of an integrated PharmD curriculum rather than offer a stand-alone Ethics course at a single time point in the curriculum. Students report appreciating this integration approach. Challenges remain to adequately assess student ability to apply Ethics principles.
Kinetic parameters

The wide variations of calculated activation energies for solid decomposition suggests that there is no discrete activated state. Further, the statistical distribution on which the calculations are based is not a realistic concept. The lowest energy possible — and most frequently occurring — is the energy of the bulk crystal. Within the crystalline solid, vibrational interactions transfer energy so rapidly that a substantial difference from the average energy is not achievable within the crystal. The lack of a statistical distribution rules out the use of the Arrhenius equation unless it is independently verified for the particular system.
Experiences of meaningful connection in the first weeks of the COVID-19 pandemic

This qualitative study explored the question, “What kinds of interactions did people experience as meaningful connections with others during the first weeks of the COVID-19 pandemic in the Unites S...
Multifidelity Data Assimilation for Physical Systems

Multifidelity methods aim to leverage the availability of models at different levels of fidelity describing the same physical phenomena and are receiving growing attention in computational science. One field that can considerably benefits from statistical multifidelity approaches is data assimilation. This chapter presents a broad overview of multifidelity methods in data assimilation for hierarchies of models and hierarchies of observations. We introduce the theoretical multifidelity Kalman filter, and discuss its practical implementation using an ensemble-based framework as the multifidelity ensemble Kalman filter (MFEnKF). The discussion builds upon the theory of linear and nonlinear control variates. Numerical examples compare the multifidelity and the traditional EnKF.
[18F]Altanserin PET Studies of Serotonin-2A Binding: Examination of Nonspecific Component

Previous analyses of the regional brain kinetics of [ 18 F]altanserin ([ 18 F]ALT) in humans, using positron emission tomography (PET), indicated the existence of a slow nonspecific binding component. These analyses involved (1) compartmental models that did not account for blood–brain barrier (BBB) passage of radiolabeled metabolites and (2) metabolite models that did. Both analyses yielded regional binding parameters that were highly correlated with the known rank order of human serotonin-2A (5HT 2 A ) receptors. In this work, the slow nonspecific binding component was further examined by applying conventional and metabolite methods to PET studies of [ 18 F]ALT and two putative metabolites: [ 18 F]altanserinol ([ 18 F]ALT-ol) and [ ,8 F]4-(4-fluorobenzoyl)piperidine ([ 18 F]4-FBP). High specific activity [ 18 F]ALT, [ 18 F]ALT-ol, and [ 18 F]4-FBP PET studies were performed in baboons at baseline and after 5HT 2 A antagonist pretreatment with ketanserin or SR 46349B (blocking data). Radioligand distribution volumes (DV) were estimated using model-based methods. Following [ 18 F]ALT-ol or [ 18 F]4-FBP injection, the radioactivity concentration in brain increased, indicating that [ 18 F]ALT-ol and [ 18 F]4-FBP (and/or their secondary metabolites) crossed the BBB, yielding cerebellar and frontal DV values that were equivalent to [ 18 F]ALT cerebellar and blocking DV values. Hence, the metabolite-generated brain radioactivity was nonspecifically distributed. Conventional models performed statistically better than metabolite models, although a greater dynamic range in the regional binding parameters was obtained by the latter method. These results support the quantification of [ 18 F]ALT data by standard kinetic methods.
Clinical utility of a novel coronary heart disease risk-assessment test to further classify intermediate-risk patients.

Background Current coronary heart disease (CHD) risk assessments inadequately assess intermediate-risk patients, leaving many undertreated and vulnerable to heart attacks. A novel CHD risk-assessment (CHDRA) tool was developed for intermediate-risk stratification using biomarkers and established risk factors to significantly improve CHD risk discrimination. Hypothesis Physicians will change their treatment plan in response to more information about a patient's CHD risk level provided by the CHDRA test. Methods A Web-based survey of cardiology, internal medicine, family practice, and obstetrics/gynecology physicians (n = 206) was conducted to assess the CHDRA clinical impact. Each physician was shown 3 clinical vignettes representing community-based cohort participants randomly selected from 8 total vignettes. For each, the physicians assessed the individual's CHD risk and selected preferred therapies based on the individual's comorbidities, physical examination, and laboratory results. The individual's CHDRA score was then provided and the physicians were queried for changes to their initial treatment plans. Results After obtaining the CHDRA result, 70% of the physician responses indicated a change to the patient's treatment plan. The revised lipid-management plans agreed more often (74.6% of the time) with the current Adult Treatment Panel III guidelines than did the original plans (57.6% of the time). Most physicians (71.3%) agreed with the statement that the CHDRA result provided information that would impact their current treatment decisions. Conclusions The CHDRA test provided additional information to which physicians responded by more often applying appropriate therapy and actions aligned with guidelines, thus demonstrating the clinical utility of the test.
Linking Helicobacter pylori to gastric cancer

Although Helicobacter pylori affects a large percentage of the population, only a small percentage of carriers develop peptic ulcers and gastric cancer. Recent investigations have begun to identify the factors that lead to these complications.
The demise of public data on the web

Data rich but cash poor, many free biological databases are on the verge of financial collapse.
Comparison of Gastric Secretion in Conscious Dogs and Cats

Summary Gastric secretion from the vagally innervated stomach in response to histamine and gastrin extract was compared in conscious dogs and cats with gastric fistulae. In both dogs and cats, the maximal rate of acid secretion was the same in response to histamine as it was in response to gastrin extract. The same dose of histamine or gastrin extract per kilogram of body weight was required to produce maximal acid response in the two species. Twice the maximal dose of histamine or of gastrin extract produced a submaximal response in the dogs but a maximal response in the cats. Pepsin output was highest to the lowest dose of histamine in both species; with increasing doses, the responses successively declined to basal level. In both dogs and cats, the pepsin output increased with increasing doses of gastrin; with supramaximal doses, the pepsin output decreased in the dogs but remained maximal in the cats. Relative to acid secretion, the cats secreted more pepsin than did the dogs.
Specifying Design Criteria for Electronic Medical Record Interface Using Cognitive Framework

As the healthcare industry transitions from paper to electronic medical records (EMRs), medical informatics researchers face the task of ensuring that the electronic presentation of the information remains usable and effective while capitalizing on the ability of EMRs to tailor information to different users. In our research, we focus on utilizing formal cognitive science methodology to guide the conversion of paper-based narrative discharge summaries to a more dynamic, structured electronic version. In this paper, we present the results of a cognitive analytic study (1) that determines a ‘core’ component in medical narratives and (2) that compares the use of structured and narrative texts by physicians with varying expertise. Specifically, we studied six psychiatrists at three levels of expertise— experts, intermediates, and novices. The subjects were given two clinical case scenarios with discharge summaries and asked to verbalize their thoughts as they read through the summaries. The interview transcripts were analyzed for recalls and inferences generated in the verbalization. Based on experts’ verbalizations, the discharge summaries were organized into a more structured form and used in the interview of other subjects. Novice-level subjects had more recall with the structured than with the narrative format. More errors were also made in recall with the narrative than with the structured text. We discuss how these results are valuable in designing an EMR interface to reduce errors and to support users of different expertise.
Operation of the Technicon Flame Photometer with Natural Gas Use in the Determination of Serum Lithium and the Semi-Micro Analysis of Serum Sodium and Potassium

Natural gas was substituted for propane gas in the oxygen-fuel mixture supplying the Technicon AutoAnalyzer flame photometer. This was accomplished by the use of a 1/3-hp rotary pump and attached manifold, which compressed the gas from the city line and supplied it at a constant pressure to the burner module of the system. A method for the automatic analysis of serum Li was devised by using K as an internal standard and comparing the output of the Li-sensitive photo-cell with that of an attenuated K-sensitive cell. In addition, a simple procedure was incorporated into the routine determination of serum Na and K: samples of insufficient volume were diluted in a solution of known electrolyte concentration, which permitted their quantitation without changing the tubing manifold or other operating components of the system.
Systematic desensitization in an experimental setting: a follow-up study.

Abstract A follow-up study was done of female college student volunteers who had been treated for marked fear of snakes using systematic desensitization under four experimental conditions. In the original study four groups were differentiated on the basis of: (1) therapeutic instructions and praise; (2) therapeutic instructions alone; (3) praise alone; and (4) neither therapeutic instructions nor praise. At follow-up Ss were reassessed on a behavioral test of their ability to approach and handle a snake, and were interviewed to determine whether they had discerned the conditions of the original experiment. Twenty-five of the original thirty-two Ss (78 per cent) were assessed a mean of 9.5 months after their experimental post-test. All four groups maintained their original gains and the inter-relationships of the groups remained stable: only instructions had a statistically significant added effect over systematic desensitization; the reinforcement and interaction factors did not attain statistical significance. From the interview data it could not be demonstrated that Ss were aware of either the instructional or reinforcement conditions of their respective groups.
Relative importance of mean velocity and bed shear on biofilm accumulation in open-channel flows

Experiments on biofilm growth were carried out to investigate whether bottom shear stress or average velocity is more appropriate as a parameter for investigating the effect of flow on biofilm formation in channel flows. The tests were conducted in two identical channels located side by side, using the same water supply. By having different bottom slopes or roughness elements, or both, tests were set up in which the flows in the two channels had equal velocities but different bottom shear stresses or equal bottom shear stresses but different velocities. Porcelain balls were used as bottom roughness elements and the accumulation of biofilm on the balls was monitored. Comparisons of the rates of biofilm accumulation indicate that the average velocity is the more important parameter.
Bounds on the power and spectral efficiency of optical fiber communication systems

A bandpass optical channel contains four degrees of freedom (DOF) corresponding to two quadrature phase and two quadrature polarization components. If independent information is sent on each of these four components, the spectral efficiency is nearly four times that achieved when utilizing a single component. For a given spectral efficiency, the minimum number of required photons per bit N p diminishes with increasing number of degrees of freedom (DOF), but the lower limit on N p , obtained when the spectral efficiency goes to zero, is 0.693 independent of DOF. For the case of an incoherent channel with square law detection and without polarization filters an upper bound to spectral efficiency and a lower bound to the number of photons per bit is obtained by assuming parallel coherent channels, but in which the same signal is transmitted in each channel. An even tighter bound on performance of the incoherent channel is obtained by computing the mutual information for a specific choice of input distribution utilizing a Markov chain approach.
Effects of methylmercury(II) on the viability of HeLa S3 cells.

Abstract HeLa S3 cells were incubated with varying concentrations of CH3HgOH for varying periods of time and the viability of the cells was determined by using the trypan blue dye exclusion test. Cell viability was found to decrease “cooperatively” with increasing CH3Hg(II) concentration in the medium. Below a certain “threshold” value of the organomercurial, viz., at CH3Hg(II) concentrations of 1 μ m and below, the cells remain alive and exhibit the viability of the control, whereas at CH3Hg(II) concentrations of 10 μ m and above, rapid cell death occurs. The kinetics of the cell death as a function of organomercurial concentration was determined, as was the ability of the cells to recover from injury once the toxicant has been removed. The effect of methylmercury on the mitotic pattern of the cells was also evaluated. At CH3Hg(II) concentrations of 1 μ m and below, the mitotic coefficient was increased by a factor of 4 over that of untreated cells after 24 hr of incubation. Treated cells became arrested preferentially during the early stages of mitosis. However, higher methylmercury concentrations, viz., 10 μ m and above, caused coagulation necrosis in the cells and no chromosome spreads could be obtained. The viability phenomena observed in this study suggest that the plasma membrane of the cells serves as the primary site of the organomercurial attack at lethal toxicant concentrations.
Successful enucleation of a giant cardiac hemangioendothelioma showing an unusual proliferation pattern

As a pathologic entity this particular subtype may not constitute a distinct tumor from the other types of clear cell tumors, as suggested in the early 1980s. However, further clinicopathologic, immunohistochemical, and ultrastructural studies of subsequent case reports support CCC as a distinct subtype of large cell carcinoma with purely clear cell features or classified into squamous or adenomatous variants, depending on the type of cellular differentiation. In our case, no squamous or adenomatous differentiation was seen, and the tumor grew into and completely occluded the right main bronchus. This biologic behavior appears to be more benign than that seen in other types of non–small cell lung cancer.
High-dose oral cyclosporin therapy for recurrent focal segmental glomerulosclerosis in children

Abstract Background:Focal segmental glomerular sclerosis (FSGS) has a high propensity for recurrence after renal transplantation, with a 50% risk for graft failure from recurrent disease. Methods:We report on the efficacy of high-dose oral cyclosporin A (CsA) in the treatment of recurrent FSGS in children. Between August 1991 and January 2003, a total of 24 patients with FSGS underwent transplantation at 1 institution. Sixteen patients (67%) had recurrent disease. In these 16 patients, CsA dose was increased gradually until remission was achieved or there was evidence of renal toxicity. Seven patients also underwent plasma exchange. Results:Thirteen patients (81%) achieved remission. Remission was complete in 11 patients and partial in 2 patients. The CsA dose necessary for inducing remission ranged from 6 to 25 mg/kg/d. Four of these patients also underwent plasma exchange. After remission, CsA dose was reduced gradually toward the standard posttransplantation regimen. Eleven of 13 responders have a functioning graft after a follow-up ranging from 10 months to 12 years. One graft was lost because of recurrent FSGS, and another graft because of recurrence and cellular rejection; noncompliance was a factor in both losses. The 3 patients with disease that did not respond to high-dose CsA therapy lost their grafts because of recurrent FSGS. A common factor in these 3 patients was the inability to increase the CsA dose because of early evidence of nephrotoxicity, evidenced by an increase in serum creatinine level. Conclusion:High-dose oral CsA therapy is effective in producing long-lasting remission of recurrent nephrotic syndrome in children with FSGS.
Plastic waste management in construction: technological and institutional issues

Abstract The main objective of a solid waste management system is to effectively safeguard the public health, safety, and welfare. The various options involved in a waste management process are landfilling, incineration, and recycling wastes into useful products. Plastics recycling, in particular, would not be successful unless the proper infrastructure to collect the waste is being set, the technology to economically reprocess the waste into new products is available, and the establishment of markets for the cost-effective use of recycled products are developed. The development of new construction materials using recycled plastics is important to both the construction and the plastics recycling industries. Extensive research investigated the use of resins based on recycled poly (ethylene terephthalate) (PET) plastic waste for the production of a high performance composite material, namely polyester concrete (PC). Resins using recycled PET offer the possibility of a lower source cost of materials for forming good quality PC. PC products also allow the long-term disposal of PET waste, an important advantage in recycling applications.
Equation of state and high pressure phase transition of NiS in the NiAs structure

Abstract Because of its close packing and high symmetry, the NiAs (B8) type is considered to be an important structure in high pressure mineral physics. To provide systematic insight on the behavior of materials assuming this structure under extreme compression, a compression study of NiAs-type NiS is presented. A fit of the data of the Birch-Murnaghan equation of state yields a bulk modulus and its pressure derivative of KoT = 156 (10) GPa and K'oT = 4.4 (12), respectively. Above 45GPa, X-ray diffraction lines of this phase were unreadable, but laser-heating of the sample induced a phase change at these pressures. Because the new phase could not be recovered at ambient conditions, and only two diffraction lines were observed at high pressures, its structure remains unknown.
Smoking motive factors: a review and replication.

A review of recent research shows that some consensus on the number, nature, and function of smoking motives or styles is emerging. Large-scale studies on the stability of motives and the utility of the smoking motive model, however, have not yet been reported. To test the factorial replicability and longitudinal stability of smoking motives, the Horn-Waingrow Smoker Survey was administered to subjects in 1973 and again in 1976, together with 20 additional items developed by Coan. Subjects were 1,340 current and former adult male smokers. Factor analyses showed that the original factor structure could be satisfactorily replicated at both times, and that the addition of Coan's new items contributed only one new factor. The 3-year stability coefficients for both continuing and former smokers ranged from. 45 to. 67, consistent with the idea that smoking motives are a relatively stable reflection of personality needs and traits.
Thymidine metabolism and DNA synthesis in crowded monolayers of animal cells.

Abstract The metabolism of thymidine in monolayer cultures of chick fibroblasts and various mammalian continuous lines of cells (Lu-106, BHK 21, L-929) was studied as a function of cell growth, aging and crowding. 1. 1. In all cell cultures the amount of TdR taken up into the acid-soluble pool, and incorporated into DNA decreased as the cells aged. The most pronounced drop of about 80–90 per cent occurred during the first two days of growth, before the decline in the slope of the growth curve. 2. 2. When trypsinized cells were seeded at high densities a similar depression of incorporation of TdR into DNA was already observed at 3–5 h after seeding. The more crowded the cells initially were, the less 3HTdR was found in the pool and the less incorporated into the DNA. Experiments with double labelling with 3HTdR and 32PO4 indicated that crowding in fact affected DNA synthesis in human, hamster and mouse cells. This immediate effect of crowding was not evident in cultures of chick fibroblasts, in which the incorporation of TdR into pools and DNA was largely independent of cell density at a given stage of growth. With aging, chick fibroblasts, as well as other cells, exhibited depression in DNA synthesis. 3. 3. In at least one line of epithelial cells (human amnion) inhibition of DNA synthesis (as measured by TdR incorporation) was shown to be due to (a) crowding per se, and (b) medium effects: DNA synthesis was inhibited in sparse cultures (no contact between cells) to which medium, taken from crowded cell cultures, was added. 4. 4. The major component of acid-soluble pool affected by aging of chick fibroblasts was thymidine triphosphate, while in LU strain of human lung cells, similar changes were observed with thymidine diphosphate.
LUMBAR SPINE IMAGING: Normal Variants, Imaging Pitfalls, and Artifacts

Accurate recognition and reporting of spine abnormalities on MRI requires knowledge of normal anatomy and its variants. This article deals with common normal variants, points out pitfalls which may be sources of errors in interpretation and describes imaging artifacts which are essential to be recognized and not mistaken for true pathologies.
A change in the stability of globin mRNA during the induction of murine erythroleukemia cells

The stability of globin mRNA in murine erythroleukemia cells (Friend cells) before and during DMSO-induced differentiation was investigated. Cells were exposed to 3H-uridine for 2 hr and then transferred to medium without the radioactive precursor. The loss of radioactivity in total RNA, poly(A)-containing RNA and globin mRNA was followed. The globin mRNA was isolated using a highly specific globin cDNA column. In uninduced cells and cells early in differentiation, the globin mRNA decays with a half-life of less than 50 hr. After 4 days of induction, the globin mRNA decays with a half-life of 17 hr, demonstrating a change in stability during the induction process. Although the stability of globin mRNA changes during induction, this is not true for total poly(A)-containing RNA. At all times of induction, the poly(A)-containing RNA decays as two populations, one with a half-life of 6 hr and the other with a half-life of 36 hr. The half-life of the rRNA also remains unchanged during differentiation.
The onset of photophosphorylation correlates with the rise in transmembrane electrochemical proton gradients

Abstract The onset of photophosphorylation was determined by exposing chloroplast thylakoids to either single or multiple light flashes of varying duration. In agreement with the results of Ort et al. (Ort, D.R., Dilley, R.A. and Good, N.E. (1976) Biochim. Biophys. Acta 449, 108–124), the permeant buffer imidazole in the presence of valinomycin and K+ did not greatly delay the onset of phosphorylation driven by multiple flash activation. In single flashes, however, the lag in the development of phosphorylation was much longer and imidazole caused a further delay. A significant ΔpH was generated by the multiple flash regime. The onset of photophosphorylation is, therefore, consistent with the rise in transmembrane ΔpH.
The persistence of social attraction in socially deprived and satiated rats

Pairs of socially deprived or satiated rats were observed for 71÷2 continuous hours in an open field. Social contact increased monotonically throughout this time, with socially deprived animals showing more attraction, and a greater increase in attraction, than satiated animals. The quality of social contact changed, however, from a predominantly active interaction, in which the most sociable animals were most mobile, to a predominantly passive huddling, in which the most sociable animals were least mobile. The results suggest that social attraction in rats is not transitory, and may serve several different functions.
Trace element concentrations in Antarctic krill, Euphausia superba

Whole Antarctic krill, Euphausia superba collected along the Western Antarctic Peninsula, were analyzed for 14 elements. Average element abundances (in parentheses) in μg/g, in descending order, were as follows: P(9940), Cu (80.5), Zn (43.5), Fe (28.0), Se (5.80), Ba (3.78), Mn (1.98), As (1.92), Ag (1.71), Ni (0.54), Cr (0.30), Cd (0.29), Pb (0.22), and Hg (0.025). Inverse relationships were found between krill length and Hg concentration as well as between As and P levels. A geographic trend of increasing Mn and P levels from southwest to northeast along the Antarctic Peninsula was Sound. Results were compared to earlier data for evidence of metal concentration changes due to anthropogenic activity over the last 15 years.
CONTRACTING MUSCLES STIFFEN THEIR APONEUROSES

![Figure][1] We're all taught that tendons connect muscles to bones, but like most generalities this statement, while true, doesn't quite capture the complexity involved in the musculoskeletal system. For example, many limb muscles have broad collagenous sheets, or aponeuroses, that lie in
Extra-High-Frequency Noise Remotely Masks and Alters Temporal Integration at Lower Frequencies

A quasi-free-field technique was used to assess the effects of extra-high-frequency-band masking on detection threshold of middle and high (1-7 kHz) frequencies. At an SPL of 60 dB, the 10- to 20-kHz masker produced a slight amount of masking. Increasing the masking level by another 5 dB produced a disproportionate increase of the detection thresholds. This increase was greatest in response to 4- and 5-kHz stimuli, and was detected with both constant and pulsed tones. Decreasing the bandwidth of the masker reduced the magnitude of the effect, but not the frequency-specific pattern of the remote masking. Extra-high-frequency masking also increased the amount of temporal integration at middle and high frequencies. The data are discussed in reference to peripheral and central neural changes associated with sensorineural hearing loss.Nous avons utilise une technique quasi-aveugle dans le but d'evaluer les effets de bandes de frequence ultrahautes de masquage sur la detection des seuils tonaux aux moyennes et ...
Amazonia: The Road to the End of the Forest

Amazonia: The Road to the End of the Forest. Video film produced by Canadian Broadcasting Corporation, distributed by Filmakers Library, 124 East 40th St., New York, NY 10016. (Part I, 50 minutes, Part II, 45 minutes).
Maternal Antibody Reactivity to Lymphocytes of Offspring With Autism

The study examined whether maternal serum antibodies from mothers of autistic children preferentially bind to lymphocytes of their autistic children compared with unaffected siblings. In a previous study, maternal serum antibodies from mothers mediated cytotoxicity with complement to lymphocytes of their autistic children. Here, maternal serum antibody binding was examined by flow cytometry. We compared levels of mothers’ serum binding against peripheral blood monocytes of their autistic children vs unaffected siblings. Because the level of binding to peripheral blood monocytes could be low, binding was examined in specific lymphocyte subpopulations. In 19 samples, the mean level of maternal serum immunoglobulin G binding to CD4 and CD8 T cells, B cells, natural killer cells, and macrophages was not significantly different from the mean level of binding to unaffected siblings. The percentages of different subpopulations were not significantly different between autistic children and unaffected siblings, although a trend (P < 0.1) emerged, i.e., autistic children displayed a higher percentage of natural killer cells and a lower percentage of B cells. These findings cast doubt on a direct effect of maternal antibodies, but do not preclude potential intrauterine pathogenic immune mechanisms in autism.
Proximal promoter of the rat brain creatine kinase gene lacks a consensus CRE element but is essential for the cAMP-mediated increased transcription in glioblastoma cells

Our previous studies have shown that transcription of brain creatine kinase (CKB) mRNA in U87-MG glioblastoma cells is stimulated by a forskolin-mediated increase in cyclic AMP (cAMP) via a pathway involving protein kinase A (PKA) and the activation of Galphas proteins. In this report, we have employed transient transfection to investigate the rat CKB gene elements essential for the cAMP-mediated induction of rat CKB transcription in human U87 cells and have mapped the transcription start site of the induced CKB transcripts. We found that the level of induced transcription from the transfected genomic rat CKB gene was the same whether transcription was driven by 2.9 kb of CKB promoter plus 5' flanking sequence or the 0.2 kb CKB promoter, suggesting that the proximal CKB promoter was essential. Also, the level of induced transcription of the chloramphenicol acetyl transferase (CAT) reporter gene driven by the 2.9 kb CKB promoter was the same as with the 0.2 kb CKB promoter. Analyses of a series of 5' deletions of the 0.2 kb proximal CKB promoter showed that the sequences between -80 bp and +1 bp were essential for the cAMP-mediated induction of CKB transcription, despite the absence of a consensus cAMP response element (CRE) sequence in that region. In agreement, gel mobility shift assays showed that nuclear extracts from U87 cells contained a protein(s) which bound specifically to a [32P]CKB DNA probe containing the -60 bp to +1 bp sequence. Mapping the 5' end of the CKB transcripts showed that the initiation of the cAMP-induced transcription occurred almost exclusively from the downstream transcription start site, apparently under the initiation direction of the nonconsensus (-28) TTAA element and not the consensus (-60) TATAAATA element. The results are discussed with regard to nuclear protein factors which may be involved, and the possible cAMP-mediated increase in CKB transcription during myelinogenesis, since the differentiation of oligodendrocytes has previously been shown to be accelerated by increased intracellular cAMP.
Cerebral salt wasting syndrome following brain injury in three pediatric patients: suggestions for rapid diagnosis and therapy.

The association between hyponatremia and intracranial pathology has been well described. When accompanied by natriuresis, hyponatremia has most commonly been attributed to inappropriate secretion of antidiuretic hormone. However, there is growing evidence to suggest that many of these patients may actually have cerebrally mediated salt losses, a disorder referred to as the cerebral salt wasting syndrome (CSWS). While this syndrome has been reasonably well described in adults, data regarding CSWS in pediatric-aged patients remains sparse. Since fluid management of these disorders is different, it is important that the clinician be able to rapidly differentiate between them. We report three cases of CSWS in acutely brain-injured children and comment on the role that early quantitation of urine volume and urine sodium concentration had in rapidly establishing the correct diagnosis.
Hydrologic gradient and vegetation controls on CH4 and CO2 fluxes in a spring-fed forested wetland

Four different habitats in a spring-fed forested wetland (Clear Springs Wetland, Panola County, Mississippi, USA) varying in hydrologic regime were examined for methane and carbon dioxide fluxes from soils over 15 and 9 months, respectively. There was an increasing gradient of CH4 flux rates from an unflooded upper-elevation forest site to an occasionally flooded bottomland forest site to a shallow permanently flooded site, and then to a deeper-water permanently flooded site. Depending on the time of year, all sites were sources of methane but only at the upper-elevation forest site, when gravimetric soil moisture content fell below 54%, was atmospheric methane consumed. On average, summer CH4 emission rates were higher than those in other seasons. A multiple regression model with soil temperature and soil redox potential as independent variables could explain 65% of the variation in CH4 flux rates. In the flooded zone, variation in CH4 flux rates was correlated with aboveground plant biomass and stem density of emergent vascular plants, and plant-mediated CH4 transport depended on plant type. The efflux of CH4 to plant biomass (Eff:B) ratio was generally lower in Hydrocotyle umbellata compared to Festuca obtusa. Compared to several other freshwater forested wetlands in the southeastern USA, this spring-fed forested wetland ecosystem was a strong source of atmospheric CH4, likely due to a long hydroperiod and high soil organic matter content. Carbon dioxide fluxes show a reverse spatial pattern than CH4 fluxes with highest CO2 emissions in the non-flooded zone at all times of the year, indicating the dominance of aerobic soil respiration. A multiple regression model also revealed a strong dependency of CO2 fluxes (r 2 = 0.73) on soil temperature and soil redox potential.
To be or not to be different: Exploration of norms and benefits of color differentiation in the marketplace

Building a strong brand identity is central for increasing brand equity. As a result, oftentimes, brands develop differentiation strategies in order to stand out from competitors. Yet, is value always gained through differentiation, or is it possible that some value could be forfeited by straying too far from established product category associations? This research examines color norms within product categories and addresses the question of whether visual differentiation is always helpful. With data for 281 top brands, the authors calculate product category color homogeneity scores for 15 product categories and 40 subcategories to empirically explore color norms. Then, these calculations are used in conjunction with brand equity scores to examine the relationship between color differentiation and brand performance. The results show that while color differentiation is helpful for some product categories, it can also be harmful for others. Specifically, the investigation reveals that adhering to color norms may be beneficial for product categories containing a dominant market leader, especially high-involvement categories. The results of this research highlight the existence of visual product category norms, and emphasize both the benefits and risks of visual differentiation should be considered.
A comparison of state space and multiple regression for monthly forecasts: U.S. Fuel consumption

Monthly consumption forecasts for U.S. oil, natural gas, and coal are made using state space and multiple regression applied to the same data. These forecasts are compared with actual consumption for a test period. The forecasts made using state space are preferred to those made using multiple regression models for both expost and exante cases. The state space forecasts track data cycles better than do the regression forecasts. Average absolute forecast errors are less for the state space models than they are for the multiple regression models.
AF1, a sequenced bioactive neuropeptide isolated from the nematode Ascaris suum.

Abstract An FMRFamide-like neuropeptide, named AF1, was isolated from head extracts of the nematode Ascaris suum using five steps of HPLC. AF1 is a heptapeptide with the amino acid sequence Lys-Asn-Glu-Phe-Ile-Arg-Phe-NH 2 . Synthetic AF1 (10 −9 to 10 −7 M) rapidly and reversibly abolished slow membrane potential oscillations of identified ventral and dorsal inhibitory motoneurons and selectively reduced their input resistances. Synaptic transmission was not blocked. In intact Ascaris, AF1 inhibited locomotory movements. This study indicates a potential physiological role for an endogenous neuropeptide in nematodes.