cssi/SciSciGPT-SciSciNet huggingface dataset:
Symbolic Techniques for Deep Learning: Challenges and Opportunities.

As the number of deep learning frameworks increase and certain ones gain popularity, it spurs the discussion of what methodologies are employed by these frameworks and the reasoning behind them. The goal of this survey is to study how symbolic techniques are utilized in deep learning. To do this, we look at some of the most popular deep learning frameworks being used today, including TensorFlow, Keras, PyTorch, and MXNet. While these frameworks greatly differ from one another, many of them use symbolic techniques, whether it be symbolic execution, graphs, or programming. We focus this paper on symbolic techniques because they influence not only how neural networks are built but also the way in which they are executed. Limitations of symbolic techniques have led to efforts in integrating symbolic and nonsymbolic aspects in deep learning, opening up new possibilities for symbolic techniques. For example, the Gluon API by Apache MXNet bridges the gap between imperative programming and symbolic execution through hybridization. Frameworks such as JANUS attempt to translate imperative programs into symbolic graphs, while approaches like DeepCheck attempt to use symbolic execution to analyze and validate imperative neural network programs. Symbolic analysis has also been paired with concrete execution in a technique called concolic testing in order to better test deep neural networks. Our study of these developments exemplifies just a few of the many ways the symbolic techniques employed by popular frameworks have the opportunity to be altered and utilized to achieve better performance.
Photochemical Charge Separation and Dye Self-Oxidation Control Performance of Fluorescein, Rose Bengal, and Triphenylamine Dye-Sensitized Solar Cells

The charge transfer kinetics between the dye, metal oxide film, and the transparent conductive oxide substrate are key to the optimization of dye-sensitized solar cells (DSSC). Here, we use surface...
Feature engineering to cope with noisy data in sparse identification

Abstract Dynamical systems play a fundamental role related understanding phenomena inherent to several fields of science. Technological advances over the previous several decades have generated a large amount of data that might be used in the inference of dynamical systems. Regardless of the sensor types adopted to perform the data acquisition procedure, it is useful to verify the existence of certain noise corruption in data. Generically, system identification is directly affected by noisy scenarios, which result in the false discovery of non-spurious models. In this work, we demonstrate how the hybridization of several machine learning techniques improves the robustness to noise with respect to the system identification assignment, advancing a pioneer methodology known as Sparse Identification of Nonlinear Dynamics (SINDy). Specifically, in the current work, we show the success of the proposed strategy from numerical examples, such as a logistic equation with forcing, Duffing oscillator, FitzHugh–Nagumo model, Lorenz attractor and a Susceptible–Infectious–Recovered modeling of SARS-CoV-2.
An Evolutionary Path for Transaction Processing Systems

Abstract Transaction processing (TP) systems have been evolving toward greater distribution, heterogeneity, and autonomy. This chapter shows that a specific evolutionary path has been followed in the development of TP systems. We introduce a classification scheme for TP systems, based on the different constraints that must be addressed in different environments. The task of implementing the traditional transaction model while not degrading system performance becomes especially difficult in certain system configurations. We identify specific problems, and abstract them into a set of five system dimensions: processes, machines, machine heterogeneity, data schemas, and sites. These dimensions involve issues such as concurrency, coordination, data homogeneity, and autonomy. The effects of distribution are now well understood: our discussion therefore focuses on steps that have been taken in the evolution toward heterogeneity and autonomy. Autonomous TP appears to offer the greatest challenges to the traditional TP model. These challenges—and various approaches to their solution—are examined.
Using Citation Data to Improve Retrieval from MEDLINE

Objective: To determine whether algorithms developed for the World Wide Web can be applied to the biomedical literature in order to identify articles that are important as well as relevant. Design and Measurements: A direct comparison of eight algorithms: simple PubMed queries, clinical queries (sensitive and specific versions), vector cosine comparison, citation count, journal impact factor, PageRank, and machine learning based on polynomial support vector machines. The objective was to prioritize important articles, defined as being included in a pre-existing bibliography of important literature in surgical oncology. Results: Citation-based algorithms were more effective than noncitation-based algorithms at identifying important articles. The most effective strategies were simple citation count and PageRank, which on average identified over six important articles in the first 100 results compared to 0.85 for the best noncitation-based algorithm (p < 0.001). The authors saw similar differences between citation-based and noncitation-based algorithms at 10, 20, 50, 200, 500, and 1,000 results (p < 0.001). Citation lag affects performance of PageRank more than simple citation count. However, in spite of citation lag, citation-based algorithms remain more effective than noncitation-based algorithms. Conclusion: Algorithms that have proved successful on the World Wide Web can be applied to biomedical information retrieval. Citation-based algorithms can help identify important articles within large sets of relevant results. Further studies are needed to determine whether citation-based algorithms can effectively meet actual user information needs.
Everybody Belongs: Changing Negative Attitudes Toward Classmates with Disabilities

The evil prosthesis of Captain Hook, the comical speech of Porky Pig, and the bumbling antics of Mr. Magoo are all examples of images in our culture which can become the basis of negative attitudes and subliminal prejudice towards persons with disabilities. These attitudes influence and underlie discriminatory acts, resulting in negative treatment and segregation. A teacher's ability to recognize and counter such images may well determine the success of inclusion and mainstreaming programs in our schools and society. Well-researched and well-written, this book offers practical guidance as grounded in solid research to schools that are wrestling with how to mainstream children with disabilities.
Some New Statistical Techniques in Geophysics

Publisher Summary Statistical theories and methods are being increasingly applied in the field of geophysics. Geophysics has made rapid strides in adopting statistical practices and many techniques have been developed for the special requirements of its various component sciences. This chapter describes some of these techniques along with preliminary discussion of some fundamental aspects of statistics. It illustrates a simple method of estimating two normal components from a bimodal distribution. The chapter also discusses the likelihood of occurrence of extreme values and the method for estimating them commonly called the theory of extreme values. It concludes with the description of the statistics of circular variable. Statistical methods are essentially of two general categories namely, descriptive and analytical. Both of these methods largely depend on the theory of probability. The extensive computations required for statistical descriptions or analysis can be done rapidly on modern computing machines. Descriptive methods are those, which compress many figures into a few to represent them adequately for the purpose at hand. However, analytical methods use the descriptive techniques to determine how well the observations agree with the theoretical model that they are assumed to follow.
Disruption of Scale Development byDelta-1Misexpression

Abstract Notch and its ligands are molecules known to be involved in many cell fate decisions. Due to the proposed role of this signaling system in the choice between feather and smooth skin fate in the embryonic chick, we sought to test whether Notch signaling may also play a role in determining scale fate.Notch-1and-2, Serrate-1and-2,andDelta-1are expressed in the scales throughout their development. Misexpression of chickDelta-1using a replication-competent retrovirus results in regions of scale loss. In addition, feather buds are often observed on some of the scuta scales. These results suggest a model in which Delta can act as an inhibitor of skin appendage fate as well as a promoter of feather fate.
A Framework for Analyzing and Testing Overlapping Requirements with Actors in Conceptual Graphs

Requirements inconsistencies, caught early in a software lifecycle, prevents unnecessary work later in that lifecycle. Testing requirements for consistency early and automatically is a key to catching errors. This paper will share an experience with a mature software project that involved translating software requirements with overlapping definitions into a conceptual graph and recommends the use of several new actors to help automatically test a requirements consistency graph.
Sex, Ancestral, and pattern type variation of fingerprint minutiae: A forensic perspective on anthropological dermatoglyphics

Objectives The majority of anthropological studies on dermatoglyphics examine the heritability and inter-population variation of Level 1 detail (e.g., pattern type, total ridge count), while forensic scientists concentrate on individual uniqueness of Level 2 and 3 detail (e.g., minutiae and pores, respectively) used for positive identification. The present study bridges the gap between researcher–practitioner by examining sex, ancestral, and pattern type variation of Level 2 detail (e.g., minutiae). Materials and Methods Bifurcations, ending ridges, short ridges, dots, and enclosures on the right index finger of 243 individuals (n = 61 African American ♀; n = 61 African American ♂; n = 61 European American ♀; n = 60 European American ♂) were analyzed. The overall effect of sex, ancestry, and pattern type on minutiae variation was assessed using a MANCOVA. ANOVA was used to identify Level 2 detail variables responsible for the variation. Logistic regression was used to classify individuals into groups. Results The effect of sex is insignificant. Ancestry is significant (Wilks' λ = 0.053 F value = 2.98, DF = 4,224, P value = 0.02), as is pattern type (Wilks' λ = 0.874 F value = 2.57, DF = 12,592.94, P value = 0.003). The ANOVA reveals that bifurcations are responsible for the variation between ancestral groups, while bifurcations and ending ridges vary between patterns. Logistic regression results suggest that total bifurcations can predict the ancestry of an individual (ChiSq = 6.55, df = 1, Prob > ChiSq = 0.01). Discussion Significant minutiae variation between ancestral groups yields information that is valuable in both a forensic and anthropological setting. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc.
Session Reliability of Web Systems under Heavy-Tailed Workloads: An Approach Based on Design and Analysis of Experiments

While workload characterization and performance of web systems have been studied extensively, reliability has received much less attention. In this paper, we propose a framework for session reliability modeling which integrates the user view represented by the session layer and the system view represented by the service layer. A unique characteristic of the session layer is that, in addition to the user navigation patterns, it incorporates the session length in number of requests and allows us to account for heavy-tailed workloads shown to exist in real web systems. The service layer is focused on the request reliability as it is observed at the service provider side. It considers the multifier web server architecture and the way components interact in serving each request. Within this framework, we develop a session reliability model and solve it using simulation. Instead of the traditional one-factor-at-a-time sensitivity analysis, we use statistical design and analysis of experiments, which allow us to identify the factors and interactions that have statistically significant effect on session reliability. Our findings indicate that session reliability, which accounts for the distribution of failed requests within sessions, provides better representation of the user perceived quality than the request-based reliability.
Discrimination in resolving systems. VI. Comparison of the diastereomers of deoxyephedrinium and ephedrinium 4'-fluoromandelates.

(-)-(R)-Deoxyephedrine forms poorly discriminating diastereomeric salts with 4'-fluoromandelic acid from 95% ethanol. Both less-soluble (L) (S)-4'-fluoromandelate and more-soluble (M) (R)-4'-fluoromandelate phases are monoclinic and unsolvated. Their solubility ratio (M/L) in 95% ethanol is only 1.2, which correlates with the similarity and small differences in their respective heats of fusion and fusion temperatures. The (R)-deoxyephedrinium and the related (1R;2S)-ephedrinium 4'-fluoromandelate systems show L-salts with higher ion-pair volumes and lower densities than their M-salts. (R)-Deoxyephedrinium salts have higher volumes than the comparable (1R;2S)-ephedrinium salts even though the resolving base (R)-deoxyephedrine lacks the benzylic hydroxy. In the solids, bilayered structures segregate polar and nonpolar molecular regions. The principle interionic interactions are hydrogen bonds between protonated secondary ammonium ions and carboxylates forming infinite chains with a six-atom repeating unit H-N(+)-H...O-C(-)-O [C(2)(2)(6)]. These are buttressed by mandelate hydroxy to carboxylate hydrogen bonds. Differing interactions between phenyl and 4'-fluorophenyl rings in the nonpolar layers of the salts correlate with the density and stability inversion.
Random vibration of uniform beams with varying boundary conditions by the dynamic-edge-effect method

Abstract In this paper, Bolotin's dynamic-edge-effect method is applied to determine both the normal modes of free undamped vibration, the cross-spectral densities of generalized random forces and random response of uniform beams with arbitrary boundary conditions. In particular, a uniform beam restrained at each end by a rotational and a translational spring is considered. Arbitrary boundary conditions can be simulated by varying each of the spring constants from zero to infinity. Cross spectral densities of generalized forces are then calculated for a random pressure field which is probabilistically weakly-stationary in time and weakly-homogeneous in space with respect to a special convecting frame of reference. Such a pressure field is believed to be a good model for jet or rocket noise in the near field. It is demonstrated that for a specific set of rotational spring constants the mean-square response attains the minimum.
The effects of chemical versus locomotory stimuli on respiratory muscle activity in the awake dog.

Abstract Using 6 chronically instrumented awake dogs, we constrasted the ventilatory and respiratory muscle EMG responses to steady-state normoxic hypercapnia with those occurring at similar levels of ventilation during steady-state treadmill exercise. During hypercapnia, increases in ventilatory output were primarily due to increments in Vt whereas during exercise, increases in minute ventilation were due primarily to increases in frequency. With either hypernea, augmentation of both inspiratory and expiratory muscle EMG activity occured but only diaphragmatic EMG activity was strongly correlated with tidal volume changes in both conditions. Using both EMGs and thoraco-abdominal pressures, we found that with increasing chemical or locomotory stimuli, during inspiration (1) diaphragmatic EMG activation occurred sooner relative to the onset of mechanical flow and (2) that respiratory muscles other than the diaphragm contributed significantly to the generation of inspiratory flow and Vt either actively or passively through recoil. Post-inspiratory activity of the crural diaphragm shortened relative to control in hypercapnia but did not change in exercise. Finally, during mild hyperpneas, end-expiratory lung volume did not change significantly in either hypercapnia or exercise but decreased at the higher levels of hyperpnea only during exercise. This may reflect differences not in the magnitude of phasic expiratory muscle activity, but rather in the degree of tonic abdominal muscle activation between the two conditions.
THE PREPUBERTAL ONTOGENY OF LUTEINIZING HORMONE RELEASING HORMONE-LIKE IMMUNOREACTIVITY IN THE DIENCEPHALON AND TELENCEPHALON OF THE MALE MEISHAN PIG BRAIN

Luteinizing hormone releasing hormone (LHRH) is a decapeptide that regulates reproductive function and behaviors in mammalian species. Because of the importance of proper reproductive function and efficiency in agricultural species, we have investigated the prepubertal ontogeny of LHRH-like immunoreactivity (IR) in the male Meishan pig. The Meishan is a Chinese breed known for reproductive traits including increased litter size and precocious puberty, but slow growth and obesity. Brains of animals from gestational day (g) 30, 50, 70, 90 and 110 and postnatal day (pn) 1, 10, 20 and 50 (duration of pregnancy averaged 114 days) were processed using a standard immunohistochemical technique utilizing a commercially available rabbit anti-LHRH antibody. LHRH-IR in cell bodies and fibers was detected at g30 entering the brain via the terminal nerve and in the septal region of the basal telencephalon. The number of immunoreactive cells increased at g50 and cells were localized primarily to the septum, organum vasculosum of the lamina terminalis, preoptic area and lateral hypothalamus, whereas immunoreactive fibers were present throughout the septum and hypothalamus and had reached the median eminence. The density and distribution of immunoreactive fibers increased by g70 and g90, but did not change dramatically from g90 to pn50. These results indicate that LHRH may be present in the Meishan brain earlier during development and fibers containing LHRH-IR appear to reach the median eminence earlier than previously reported for the domestic pig. These results suggest a breed difference in the ontogeny of reproductive control systems in the pig. Future studies utilizing direct comparisons between domestic and Chinese breeds will be required to investigate the apparent differences in the ontogeny of LHRH-containing systems in the pig.
Modulation of lymphocyte proliferative responses by a canine Lyme disease vaccine of recombinant outer surface protein A (OspA)

The modulation of human lymphocyte proliferative responses was demonstrated with a recombinant outer surface protein A (OspA) vaccine preparation for the prevention of Borrelia burgdorferi infection. After exposure to either the unaltered vaccine preparation or OspA prepared in saline, normal lymphocyte responses to the mitogens concanavalin A, phytohemagglutinin-M or pokeweed mitogen, or the antigen BCG were consistently reduced. Whole cell extracts of B. burgdorferi also modulated immune responses but required a much greater quantity of protein than needed for the OspA preparation. The magnitude of modulation was directly dependent on the quantity of OspA. OspA interferes with the response of lymphocytes to proliferative stimuli including a blocking of cell cycle phase progression. Future studies designed to delete the particular region or component of the OspA molecule responsible for this effect may lead to improved vaccine preparations.
A stable HLLC Riemann solver for relativistic magnetohydrodynamics

In this short note we improve on an HLLC Riemann solver for relativistic magnetohydrodynamics (MHD). The improvement consists in realizing that density jumps as well as jumps in the transverse velocity can be safely incorporated into the HLLC Riemann solver for relativistic MHD. The iteration process described here is low cost, stable and fast-converging. It obviates the need to have one formulation when the longitudinal magnetic field is non-zero and another when it vanishes. Excellent operation is shown on several test problems.
STEREOSPECIFICITY OF ERYTHROCYTE ACETYLCHOLINESTERASE.

Abstract Lactoylcholine is a choline ester which contains an asymmetric carbon atom in the acid portion of the molecule. A study of the hydrolytic rate of the enantiomers of this choline ester by human erythrocyte acetylcholinesterase revealed that the l (+) isomer is hydrolyzed at least four times greater than the d (−) isomer. The p S activity curve obtained for lactoylcholine assumed a typical acetylcholine-like bellshaped form. The p S optimum for l (+) isomer of lactoylcholine in comparison to acetylcholine shifted to a lower value, indicating a higher reaction velocity maximum at higher substrate concentrations. The differences in the relative enzymic rates of hydrolysis of the two isomers was explained by proposing the presence of an asymmetric reactive site on the enzyme surface facilitating the hydrolysis of one isomer better than the other.
Ideology at a Canadian shelter for battered women: A reconstruction

Abstract Feminist organizations seek to end gender injustice and positively reorient societal structures. Hindering the achievement of this mission is their lack of a coherent explanation of present social arrangements, their lack of clearly defined ideals, and their lack of agreed-upon change strategies. To address these problems, a method for analysing and reconstructing organizational ideology is applied to the statement of philosophy of a shelter for battered women and their children. Both the research approach and empirical findings stress the interplay between affinity and distancing in the production of critical but hopeful thinking and constructive action.
Discussion of “Separating Winners from Losers among Low Book-to-Market Stocks using Financial Statement Analysis”

The conference paper by Mohanram (2005) provides evidence on the success of contextual financial statement analysis in the low book-to-market (i.e., glamour) stock setting. The economic benefits of the strategy are concentrated in the identification of glamour firms that will ultimately underperform the market. In contrast to traditional accounting-based anomalies, Mohanram’s growth-based trading strategy is stronger among large, heavily followed firms, suggesting that the mechanism behind the mispricing of glamour firms is different than the traditional information environment and dissemination arguments found in other settings. Despite the robustness of the reported results, the strategy faces implementation constraints due to (1) the relative costs associated with gathering industry-adjusted data and (2) the frictions and costs associated with capitalizing on expected price declines over a long horizon. Finally, the relative benefits of contextual analysis need to be assessed against the predictive benefits accruing to traditional financial statement analysis-based investment techniques.
Pneumonia Pathogen Characterization Is an Independent Determinant of Hospital Readmission

BACKGROUND Hospital readmissions for pneumonia occur often and are difficult to predict. For fiscal year 2013, the Centers for Medicare & Medicaid Services readmission penalties have been applied to acute myocardial infarction, heart failure, and pneumonia. However, the overall impact of pneumonia pathogen characterization on hospital readmission is undefined. METHODS This was a retrospective 6-year cohort study (August 2007 to September 2013). RESULTS We evaluated 9,624 patients with a discharge diagnosis of pneumonia. Among these patients, 4,432 (46.1%) were classified as having culture-negative pneumonia, 1,940 (20.2%) as having pneumonia caused by antibiotic-susceptible bacteria, 2,991 (31.1%) as having pneumonia caused by potentially antibiotic-resistant bacteria, and 261 (2.7%) as having viral pneumonia. The 90-day hospital readmission rate for survivors (n = 7,637, 79.4%) was greatest for patients with pneumonia attributed to potentially antibiotic-resistant bacteria (11.4%) followed by viral pneumonia (8.3%), pneumonia attributed to antibiotic-susceptible bacteria (6.6%), and culture-negative pneumonia (5.8%) ( P P 4, cirrhosis, and chronic kidney disease. Culture-negative pneumonia was independently associated with lower risk for 90-day readmission. CONCLUSIONS Readmission after hospitalization for pneumonia is relatively common and is related to pneumonia pathogen characterization. Pneumonia attributed to potentially antibiotic-resistant bacteria is associated with an increased risk for 90-day readmission, whereas culture-negative pneumonia is associated with lower risk for 90-day readmission.
Effects of Nafion loading in anode catalyst inks on the miniature direct formic acid fuel cell

Abstract Nafion, within the anode and cathode catalyst layers, plays a large role in the performance of fuel cells, especially during the operation of the direct formic acid fuel cell (DFAFC). Nafion affects the proton transfer in the catalyst layers of the fuel cell, and studies presented here show the effects of three different Nafion loadings, 10 wt.%, 30 wt.% and 50 wt.%. Short term voltage–current measurements using the three different loadings show that 30 wt.% Nafion loading in the anode shows the best performance in the miniature, passive DFAFC. Nafion also serves as a binder to help hold the catalyst nanoparticles onto the proton exchange membrane (PEM). The DFAFC anode temporarily needs to be regenerated by raising the anode potential to around 0.8 V vs. RHE to oxidize CO bound to the surface, but the Pourbaix diagram predicts that Pd will corrode at these potentials. We found that an anode loading of 30 wt.% Nafion showed the best stability, of the three Nafion loadings chosen, for reducing the amount of loss of electrochemically active area due to high regeneration potentials. Only 58% of the area was lost after 600 potential cycles in formic acid compared to 96 and 99% for 10 wt.% and 50 wt.% loadings, respectively. Lastly we present cyclic voltammetry data that suggest that the Nafion adds to the production of CO during oxidation of formic acid for 12 h at 0.3 V vs. RHE. The resulting data showed that an increase in CO coverage was observed with increasing Nafion content in the anode catalyst layer.
Antibiotic regimen and the timing of prophylaxis are important for reducing surgical site infection after elective abdominal colorectal surgery.

Abstract Background: Surgical site infections (SSIs) cause morbidity after elective colorectal surgery, and antibiotic prophylaxis can decrease SSIs. The aim of this study was to determine compliance with an antibiotic administration protocol, including regimen, initial dose timing, and re-dosing, and determine the risk of SSI associated with each. We hypothesized that appropriate antibiotic administration reduces the risk of SSI. Methods: Retrospective review from a prospective database of a random sample of patients undergoing elective abdominal colorectal procedures with anastomosis. Antibiotic regimens, initial dose timing (IDT), and re-dosing were evaluated. Appropriate regimens covered gram-positive cocci, gram-negative bacilli, and anaerobes. The IDT was considered proper if completed within 30 min prior to incision; re-dosing parameters were determined pharmacokinetically for each agent. The main outcome was SSI. Sequential logistic models were generated: Model 1 assessed antibiotic administration...
How the formation of Indonesia destroyed Australia's rain forest

[1] A little more than 3 million years ago, a climatic upheaval forever changed Australia's western coast. Over the span of 200,000 years the southward flowing waters of the Leeuwin Current cooled by 2°–3°C, decreasing coastal precipitation and converting northwestern Australia's rain forests to semiarid grasslands. By measuring the isotope ratios and chemical composition of preserved shells left by ancient single-celled organisms, Karas et al. reconstructed the hydrologic signature of the geologic upheaval that triggered the sudden cooling. During the Pliocene (approximately 4–3 million years ago), tectonic activity led to the formation of a number of small islands in the Indonesian Archipelago. This protruding land restricted the Indonesian Throughflow (ITF), a current that carries warm, fresh, tropical Pacific water through the island chain and feeds the Leeuwin Current. (Paleoceanography, doi:10.1029/2010PA001949, 2011)
Effects of repeated cycles of feed intake shifts on growth, feed efficiency and endocrine profiles of wether lambs

Estell, R.E., Havstad, K.M., Heird, C.E., Fredrickson, E.L., Hallford, D.M. and Shupe, W.L., 1993. Effects of repeated cycles of feed intake shifts on growth, feed efficiency and endocrine profiles of wether larnbs. Small Rumin. Res., 10:103-118. Fifteen wether lambs (average BW 28.8 + 1.8 kg) were used in a 128-d trial to examine effects of cyclical feeding changes on growth, feed efficiency and endocrine profiles. Control lambs were fed a 40% concent:~"ate diet (40C) at 1.5 × NEro requirement during period 1 (64 d). Another group ( 1 × / 2X ) was fed 40C at 1 and 2×NEm in 4-d intervals during period 1; a third group (70/10) was fed 70% and 10% concentrate diets in 4-d intervals during period 1. To achieve dry matter intake comparable to controls, 70/10 lambs were fed at 1.79 (70C) and 1.21 (10C) ×NEro. All lambs were placed on the control diet during period 2 (32 d) and increased to 2 × maintenance during period 3 (32 d). During period 2, ADG and gain/feed of control lambs tended to be greater (P< 0.10) than for lambs fee( alternating treatments. Liver weight as a percentage of hot carcass weight was greater (P< 0.05) for controls than for lambs fed alternating treatments. Hot carcass weight (P= 0.07 ) and dressing percentage (P=0.09) tended to be greater for the 70/10 treatment than for controls. The 1 X/2 X trealment lowered (P< 0.05 ) serum cholesterol compared with other groups on d 65, but not on d 0 or 129. Smaller liver weight per unit of hot carcass weight for lambs in the 1 X/2 × and 70/10 treatments suggests a possible reduction of maintenance requirements.
Determination of NOE “silent” dipolar interactions between magnetically equivalent nuclei: Application to poly(dA) · poly(dT)

The ratio of the spin–spin relaxation rate, R2, to the selective spin–lattice relaxation rate, R, can be used to detect and determine the magnitude of dipolar interactions between magnetically equivalent unclei in macromolecules. We use this method to show that there is strong interaction between adjacent AH2 protons in poly(dA) · poly(dT). The largest possible AH2–AH2 distance that will account for the observed magnitude of the interaction is ∼3.5 A, provided the AH2 protons are located close (within 0.6 A) to the helix axis. Structures with shorter AH2–AH2 separations could account for the nmr data, but they are rejected because they would reduce the interbase separation to unacceptably small values. A comparison of rates measured at 360 and 500 MHz shows that the chemical-shift anisotropy makes a negligible contribution to the observed relaxation rates.
Intrathecal capsaicin enhances one-kidney renal wrap hypertension in the rat

Afferent renal nerves (ARN) have been implicated in the development of one-kidney renal wrap (1K-WRAP) hypertension. The role of renal nerves in desoxycorticosterone acetate-salt (DOCA) hypertension, a low-renin model of hypertension, is controversial. The present study was designed to determine if spinal substance P (SP) and/or calcitonin gene-related peptide (CGRP) in ARN affects the development of 1K-WRAP or DOCA hypertension in adult rats. Selective long-term partial depletion of spinal SP and CGRP within small primary afferent nerve fibers including unmyelinated ARN was achieved by intrathecal administration of capsaicin. After capsaicin treatment, 1K-WRAP hypertension was induced by removing the right kidney and wrapping the left kidney with a figure-8 ligature. In a second group of rats, DOCA hypertension was induced by subcutaneous application of desoxycorticosterone pellets after unilateral nephrectomy. Systolic arterial pressure was monitored for 8 weeks by tail cuff plethysmography after which direct blood pressure measurement was performed followed by immunohistochemistry. Intrathecal capsaicin administration had no significant effect on SP-ir and CGRP-ir of ARN soma located within thoracic dorsal root ganglia whereas immunoreactivity against these peptides was reduced by one third to one half in the dorsal horn, indicating effective long-term spinal depletion of these neuropeptides. Intrathecal capsaicin enhanced the development of 1K-WRAP hypertension, since arterial pressure was greater in the treated group. In contrast, DOCA hypertension was unaffected by capsaicin pretreatment. Considering the neurotoxic action of capsaicin for SP-ir and CGRP-ir unmyelinated primary afferent neurons, we hypothesize that spinal SP, CGRP and/or related peptides existing in ARN and other capsaicin-sensitive unmyelinated primary afferent neurons in the lower thoracic spinal cord may ameliorate 1K-WRAP hypertension, but not DOCA hypertension.
Impurity distribution in high-efficiency silicon avalanche diode oscillators

The influence of impurity distribution on the performance of high-efficiency silicon avalanche diode oscillators has been investigated for a number of diffusion profiles and doping densities of ionized donors. p+-n-n+mesa diodes with diameters ranging from 0.005 to 0.030 inch, were designed with abrupt, hyperabrupt, graded, and linearly graded junctions with doping densities varying from 1014to 2 × 1015cm-3and depletion region width 4 µm ≤ W ≤ 8 µm. The devices were operated at L-band with 40 percent efficiency. The high-frequency characteristics of the avalanche devices have shown that high-efficiency performance can be achieved with complex waveforms of current.
SEMICLASSICAL EXPRESSION OF THE SPIN PROPAGATOR

We use a continuous-time path integral to obtain the semiclassical propagator for minimal-spread spin coherent states. We pay attention to the extra phase. This extra correction of phase is related to an anomaly in the fluctuation determinant. We show that if this extra factor is included, the semiclassical propagator has the correct short time behaviour to O(T2), and demonstrate its consistency under dissection of the path.
The high temperature defect structure of CoO

Abstract The oxygen partial pressure and temperature dependence of the departure from stoichiometry, electrical conductivity and Seebeck coefficient of CoO single crystal and polycrystalline specimens were measured in the range 1000 ≤ T ≤ 1400°C and 10−8·5 ≤ Po2 ≤ 1 atm. It is shown that the data are consistent with the behavior of a p-type semiconductor having Co vacancies in various states of ionization, the singly ionized state predominating over the greatest part of the range of oxygen excess. The activation energy for the formation of singly ionized vacancies was found to be 0·98 eV while that for doubly ionized vacancies was 1·75 eV. At oxygen pressures ≥ 10−5 atm, established by pure oxygen, the effective concentration of impurities was on the order of the vacancy concentration and influenced the pressure dependence of the electrical conductivity. The use of CO/CO2 mixtures to produce low oxygen pressures resulted in a compensation of the impurities by dissolved carbon. This was verified by measurements on Li-doped specimens. At large departures from stoichiometry (Po2 ≈ 1 atm) interaction between vacancies affects the observed pressure dependence. The drift mobility of holes was about 0·45 cm2/V-sec at 1200°C with |d log μ/d (kT)−1|
A method for estimating rates of nucleotide substitution using DNA sequence data.

An estimate of the average number of evolutionarily acceptable substitutions per nucleotide since the most recent common ancestor of a pair of homologous sequences is found which uses nucleotide sequence data. The estimate is derived assuming a Poisson-like model for the evolutionary process. A method is also suggested for analyzing nucleotide sequence data in M homologous sequences (M ⩾ 3). A simulation study is reported showing that the estimates are satisfactory providing there is sufficient homology between the sequences. To demonstrate the methods a numerical example using some β-globin data is presented.
A new off‐center defect system, RbCl:Li+, studied with dielectric techniques under hydrostatic pressure

RbCl crystals with Li+ doping, spanning a concentration range of nearly three orders of magnitude, are systematically studied in their real and imaginary dielectric response under hydrostatic pressure (up to 7 kbar). A dielectric constant anomaly and loss peak around 40 K is found, which can be fitted to a Langevin-Debye behavior of classical dipoles with an activation energy for reorientation of 510 K. For small Li+ doping (N < 1018 cm−3), this dielectric response scales with the Li+ concentration, yielding (for Lorentz corrected fields) a dipole moment of 〈p〉 = 0.52 e A. The potential barrier for the Li+ dipole reorientation is found to be drastically reduced under hydrostatic pressure, shifting the observable relaxation to low temperatures. Though this pressure tuning process is interrupted by the NaCl CsCl structural phase-transition at 4.6 kbar, it can be extrapolated that for about 8 kbar (i.e., 2% compression) RbCl:Li+ should become a tunneling system similar to KCl:Li+. Consequences of the observed behavior for the theoretical understanding and host-lattice trends of Li+ off-center defects and for the behavior of FA(Li) centers are discussed. RbCl-Kristalle, dotiert mit Li+ uber einen Konzentrationsbereich von drei Grosenordnungen, werden systematisch in ihrem realen und imaginaren dielektrischen Verhalten unter hydrostatischem Druck (bis zu 7 kbar) untersucht. Eine Anomalie der Dielektrizitatskonstante und ein Verlustmaximum werden bei 40 K gefunden, die mit einem Langevin-Debye-Verhalten klassischer Dipole und einer Reorientierungs-Aktivierungsenergie von 510 K verstanden werden konnen. Fur kleine Li+-Dotierungen (N < 1018 cm−3) ist die Starke dieser dielektrischen Effekte proportional zur Li+-Konzentration und ergibt (fur Lorentzfeldkorrektur) ein Dipolmoment von 0,52 e A. Die Potentialbarrieren fur die Li+-Reorientierung werden unter hydrostatischem Druck drastisch reduziert, so das sich die beobachtbare dielektrische Relaxation nach tiefen Temperaturen verschiebt. Obwohl dieses Druckverhalten bei 4,6 kbar durch die Phasenumwandlung von der NaCl- in die CsCl-Gitterstruktur unterbrochen wird, kann man extrapolieren, das bei etwa 8 kbar (d. h. 2% Kompression) RbCl:Li+ ein Tunnelsystem ahnlich wie KCl:Li+ werden sollte. Konsequenzen des beobachteten Verhaltens fur das theoretische Verstandnis von Li+-Off-Center-Effekten und fur das Verhalten von FA(Li)-Zentren werden diskutiert.
Laminar-Turbulent Transition Behind Discrete Roughness Elements in a High-Speed Boundary Layer

Computations are performed to study the flow past an isolated roughness element in a Mach 3.5, laminar, flat plate boundary layer. To determine the effects of the roughness element on the location of laminar-turbulent transition inside the boundary layer, the instability characteristics of the stationary wake behind the roughness element are investigated over a range of roughness heights. The wake flow adjacent to the spanwise plane of symmetry is characterized by a narrow region of increased boundary layer thickness. Beyond the near wake region, the centerline streak is surrounded by a pair of high-speed streaks with reduced boundary layer thickness and a secondary, outer pair of lower-speed streaks. Similar to the spanwise periodic pattern of streaks behind an array of regularly spaced roughness elements, the above wake structure persists over large distances and can sustain strong enough convective instabilities to cause an earlier onset of transition when the roughness height is sufficiently large. Time accurate computations are performed to clarify additional issues such as the role of the nearfield of the roughness element during the generation of streak instabilities, as well as to reveal selected details of their nonlinear evolution. Effects of roughness element shape on the streak amplitudes and the interactions between multiple roughness elements aligned along the flow direction are also investigated.
Protein turnover and proteolysis during sporulation of Bacillus subtilis

A two-dimensional electrophoretic method was used to show that protein degradation occurs immediately after the end of exponential growth but that its occurrence is masked in the usual assay methods for a 2-h period and that degradation is apparently nonselective with respect to protein molar mass or charge. The results suggest that considerable reutilization of internal amino acids may occur during sporulation regardless of the size of the external chase. Finally, the levels of intracellular proteinase activities present even at the end of exponential phase growth, as measuredin vitro, are sufficient to account for the maximum rates of protein degradation observedin vivo.
Multichannel imaging using diffractive optics

A multiple imaging system can produce a two-dimensional array of images from a single input object. The basic components of our implementation are a high-performance Fourier processor and a suitably designed diffraction grating that is placed in the frequency phase. We have made use of a single diffractive element Fourier transform lens, corrected for coma, astigmatism, and field curvature. The lens is designed to have the proper amount of distortion to produce an optical transform. The optical processing system consists of two of these lenses spaced a distance equal to the sum of their focal lengths. We employ an iterative algorithm to produce the necessary phase diffraction grating that generates a multiplicity of equal energy plane waves from a single incident plane wave. The method is based on an iterative Fourier- transform scheme that makes use of known constraints to synthesize the phase structure. The constraints include the known Fourier modulus (array of point sources), the phase-only requirement in the grating plane, and fabrication requirements such as discrete phase levels. The iterative algorithm provides an efficient means to calculate grating profiles that give rise to large arrays of images. System performance over a relatively wide field-of-view is characterized by calculating the modulation transfer function at various points in the image plane.
Treatment with low-dose oral etoposide in patients with myelodysplastic syndromes

Forty-three patients with myelodysplastic syndromes (MDS) received treatment with oral etoposide 50 mg/day for 21 consecutive days every 4 weeks. Eighteen patients (42%) experienced hematological responses, including 12 of 17 (70%) patients with chronic myelomonocytic leukemia (CMML). Three of five CMML patients who failed treatment with hydroxyurea experienced major hematological responses with oral etoposide. Median response duration exceeded 9 months (range: 4-49 + months), and one patient remains in an unmaintained complete remission for 4 years. Toxicity included nausea/vomiting in five patients, fever (four patients), infection (three patients), mucositis (two patients), and anorexia (two patients). Two patients had grade 4 neutropenia with sepsis necessitating treatment withdrawal. We conclude that low-dose oral etoposide has remitting activity in MDS and is an effective treatment alternative for patients with CMML.
Role of chicken IL-2 on γδ T-cells and Eimeria acervulina-induced changes in intestinal IL-2 mRNA expression and γδ T-cells

Continuous culture of concanavalin A (Con A)-activated spleen cells in the presence of chicken recombinant IL-2 (rIL-2) promoted preferential growth of gammadelta T-cells. These cells displayed a high level of spontaneous cytotoxicity against LSCC-RP9 tumor cells, an avian NK cell target. Stimulation of IL-2-dependent gammadelta T-cells with Con A induced IFN-gamma and IL-2 mRNA transcripts, whereas stimulation with rIL-2 induced only IFN-gamma mRNA. Subcutaneous injection of 3-week-old chickens with IL-2 DNA increased splenic cells, expressing the CD8 and gammadelta TCR antigens. To investigate the role of IL-2 and gammadelta T-cells in parasitic infection, chickens were orally infected with Eimeria acervulina and the expression of IL-2 mRNA transcripts in the spleen and duodenum and the percentage of gammadelta T-cells in the duodenum were examined. Following both, the primary and secondary infections, a significant enhancement of IL-2 mRNA transcripts in the spleen and intestine and increased percentage of intraepithelial gammadelta T-cells in the duodenum were observed. These results indicate that host immune responses to E. acervulina involve an up-regulation of IL-2 secretion and an increased duodenum gammadelta T-cells.
Nanoethics in a nanolab: ethics via participation.

A participant–observer who is both informed and interested in ethical issues, and is embedded within a nanotechnology research and development facility may be able to influence the ethical awareness of researchers in nanotechnology, and tease out the societal implications of the work being conducted. Two inter-disciplinary methods were employed: (1) regular involvement in the technical and scientific research at the facility by the participant–observer, and (2) repeated interactions and discussions between the participant–observer and the scientists. As a result of this qualitative approach, an ethics questionnaire was developed and tested. This questionnaire has been incorporated into the admissions procedures for researchers as they commence use of the nanotech facility. The questionnaire highlights the importance of ethical issues in nanotechnology research and draws researchers into an engagement with possible ethical consequences and with future societal implications of their work.
Tooth contacts and stability before and after occlusal adjustment

A study was undertaken to analyze the possible relationship between the number and type of tooth contacts before, immediately after and 16 weeks after occlusal adjustment and their influence upon occlusal stability. The data collected from 10 adult subjects who required an occlusal adjustment indicated the following: 1. Six of the ten subjects had no clinically perceptible "slide from centric relation" 6 weeks after occlusal adjustment, and the number of teeth and number of contacts were virtually the same immediately after 6 weeks after occlusal adjustment. 2. The remaining four subjects, whose occlusions had relapsed after adjustment, had one dental arch that included a missing tooth. It would seem that dental arches interrupted with extraction spaces do not remain stable with occlusal adjustment alone. 3. The type of tooth contacts that are the most stable are those of a cup against a flat plane (e.g., bottom of a fossa or marginal ridge) or those of a combination of a cup against a flat plane and one or more inclined planes.
Greenbelt, Maryland: A federally planned community

New “garden city” off to a good start. Manager charter now in operation with constructive citizen activity behind it.