cssi/SciSciGPT-SciSciNet huggingface dataset:
Weak Formulations of Elliptic Boundary Value Problems

In this chapter, we consider weak formulations of some elliptic boundary value problems and study the well-posedness of the variational problems. We begin with a derivation of a weak formulation of the homogeneous Dirichlet boundary value problem for the Poisson equation. In the abstract form, a weak formulation can be viewed as an operator equation. In the second section, we provide some general results on existence and uniqueness for linear operator equations. In the third section, we present and discuss the well-known Lax-Milgram Lemma, which is applied, in the section following, to the study of well-posedness of variational formulations for various linear elliptic boundary value problems. We also apply the Lax-Milgram Lemma in studying a boundary value problem in linearized elasticity; this is done in Section 8.5. The framework in the Lax-Milgram Lemma is suitable for the development of the Galerkin method for numerically solving linear elliptic boundary value problems. In Section 8.6, we provide a brief discussion of two different weak formulations: the mixed formulation and the dual formulation. For the development of Petrov-Galerkin method, where the trial function space and the test function space are different, we discuss a generalization of Lax-Milgram Lemma in Section 8.7. Most of the chapter is concerned with boundary value problems with linear differential operators. In the last section, we analyze a nonlinear elliptic boundary value problem.
Nuclear Magnetic Resonance in Polypeptide Liquid Crystals

Some twenty years ago it was found that synthetic polypeptides, Open image in new window , can exist as rigid, rodlike α-helical molecules, in contrast with the random coil conformation adopted by most other synthetic polymers in solution. This observation with its implications in the study of protein structure stimulated a concentrated and sustained investigation of the dilute solution (1–5 wt.% polymer) properties of this class of polymers. In more concentrated polypeptide solutions (10–15 wt.% polymer), poly (γ-benzyl-L-glutamate) (PBLG; R = CH2CH2COOCH2C6H5), forms a lyotropic liquid crystal. Robinson1 extensively characterized the PBLG liquid crystal and found similarities between its supra-molecular structure and the structure existing in thermotropic cholesteric liquid crystals.
Nonlinear Dynamics in the SSC — Experiment E778

A 1% variation in the cost of an accelerator was not very important forty years ago, when a cyclotron fitted into a single room. Today, when the net cost of an accelerator such as the SSC is measured in billions of dollars, it is much more important to design for an optimum balance between cost and performance. While it is irresponsible to increase the cost of an accelerator more than necessary to make it work “sufficiently” well, it is more irresponsible to construct a machine which almost works, but does not. The problems of large accelerator design lie on the horns of this dilemma. Some aspects of a successful design, such as building in flexibility to enable development in initially unforeseen directions, are almost impossible to quantify. Architectural problems such as these are not addressed here, despite their subtlety and relevance. Neither is the most difficult task addressed — the task of defining what is meant by an accelerator working “sufficiently” well, in terms of needed performance parameters, such as luminosity, lifetime, or linear aperture. Instead, this chapter concentrates on the accelerator physics processes which are expected to limit the performance of the SSC.
Current Kinetic Modeling Techniques for Continuous Flow Combustors

Analytical models existing in the open literature for gas turbine continuous flow combustors are reviewed and discussed from the point of view of predictions of pollutant emissions. Particular emphasis is placed on the kinetic aspects of the models involving liquid fuel droplet evaporation and/or combustion and homogeneous chemical kinetics for hydrocarbon/air combustion. A brief summary of the various flow models is also included. Comparisons with data obtained from experimental or practical combustors are made where appropriate, and suggestions for further research are listed.
Functional Connectivity in Term Neonates With Hypoxic-Ischemic Encephalopathy Undergoing Therapeutic Hypothermia.

Abstract Background We investigated whether therapeutic hypothermia and rewarming impact functional connectivity using electroencephalography (EEG) as a measure in neonates with hypoxic-ischemic encephalopathy. We hypothesized that EEG coherence and voltage correlations would be lower and phase lag greater in infants with hypoxic-ischemic encephalopathy than control subjects and that functional connectivity would evolve during therapeutic hypothermia with the greatest improvement occurring during rewarming. Methods This study was a retrospective study of 14 term neonates (greater than 37 weeks) with moderate hypoxic-ischemic encephalopathy who underwent therapeutic hypothermia and rewarming. Continuous EEG and video monitoring was conducted for 96 hours during therapeutic hypothermia and rewarming. The primary quantitative EEG measures of functional connectivity were coherence, phase lag, and voltage correlations. These EEG parameters were compared with a cohort of normal age-matched neonates. Results Neonates with hypoxic-ischemic encephalopathy had marked decreases in power, coherences, and voltage correlation and increases in phase lag when compared with control neonates. However, there were no significant changes in these measures between therapeutic hypothermia and rewarming. Conclusions Neonates with hypoxic-ischemic encephalopathy demonstrate significant abnormalities in functional connectivity compared with control subjects. These abnormalities persist through therapeutic hypothermia and rewarming and are not altered after rewarming. Although hypoxic-ischemic encephalopathy is associated with impaired functional brain connectivity, there is no evidence, using quantitative EEG measures, that therapeutic hypothermia or rewarming either improves or exacerbates these abnormalities in connectivity.
Preliminary results on the density matrix structure of the first beryllium1S excited state

The 1- and 2-matrix analyses of a trial configuration interaction wave function, constructed over an orthonormal basis set, for the first beryllium1S excited state are presented. The results are compared with those of the ground state (also reported) to clarify the changes undergone by the natural orbitals and geminals. The changes in the nature of the electron correlation effect are also examined.
Gastric cancer risk stratification and surveillance after Helicobacter pylori eradication: 2020.

Gastric cancer remains one of the most common causes of cancer deaths worldwide. The best current option for reducing gastric cancer deaths is Helicobacter pylori eradication combined with risk assessment and surveillance programs for those deemed to be at high risk for gastric cancer so as to identify lesions at a stage amenable to curative therapy. In this issue, Nam et al1 report a retrospective study of Helicobacter pylori eradication on gastric cancer incidence among 10,328 Korean adults undergoing health checkups including an H pylori test-and-treat program. With a median follow-up of time 5.5 years, they report that H pylori eradication resulted in a significant reduction of gastric cancer incidence in comparison with individuals with persistent infection (eg, hazard ratio [HR] 0.29). Additional important risk factors included atrophic gastritis, family history of gastric cancer, and possibly higher body mass index, which was significant in 1 model but not the other. They also noted that a low serum high-density lipoprotein (HDL) level was associated with a significant increased cancer risk (HR 2.67) when adjusted for low-density lipoprotein (LDL) level and use of lipid-lowering drug.
Structures of a RAG-like transposase during cut-and-paste transposition

Transposons have had a pivotal role in genome evolution1 and are believed to be the evolutionary progenitors of the RAG1–RAG2 recombinase2, an essential component of the adaptive immune system in jawed vertebrates3. Here we report one crystal structure and five cryo-electron microscopy structures of Transib4,5, a RAG1-like transposase from Helicoverpa zea, that capture the entire transposition process from the apo enzyme to the terminal strand transfer complex with transposon ends covalently joined to target DNA, at resolutions of 3.0–4.6 A. These structures reveal a butterfly-shaped complex that undergoes two cycles of marked conformational changes in which the ‘wings’ of the transposase unfurl to bind substrate DNA, close to execute cleavage, open to release the flanking DNA and close again to capture and attack target DNA. Transib possesses unique structural elements that compensate for the absence of a RAG2 partner, including a loop that interacts with the transposition target site and an accordion-like C-terminal tail that elongates and contracts to help to control the opening and closing of the enzyme and assembly of the active site. Our findings reveal the detailed reaction pathway of a eukaryotic cut-and-paste transposase and illuminate some of the earliest steps in the evolution of the RAG recombinase. Analysis of multiple structures of the Helicoverpa zea DNA transposase Transib, determined by X-ray crystallography and cryo-electron microscopy, reveals the detailed pathway of the transposition reaction and sheds light on the evolution of the RAG recombinase.
Massive MIMO Uplink Channel Estimation using Compressive Sensing

Over the past decades, wireless communication systems have made a real revolution. Huge amounts of information circulate on the networks every second. To meet the growing demand for data throughput, massive multiple-input multiple-output (MIMO) has been proposed as a key technology for future wireless communications by offering substantial energy gain and spectral capacity. However, the advantages of such a system generally requires that the channel state information should be available on the transmitter (CSIT). For this purpose, this work presents the implementation of a new channel estimation technique based on training sequence in Time Division Duplex (TDD) mode. As it is known, wireless communication tends to be sparse, that is why, in this paper, we will focus on this property and propose a new approach based on compressed sensing technique to estimate the Channel Impulse response (CIR) of the massive MIMO system. As a simulation results, it has been shown that the proposed algorithm Block Orthogonal Matching Pursuit (B-OMP) outperforms the old approach known as Adaptive Orthogonal Matching Pursuit (AOMP) especially in terms of Bit Error Rate (BER) where it makes a gain of 1 dB over AOMP algorithm. However, in terms of Normalised Mean Square Error (NMSE), both of them have shown the same performance, where both of curves are superimposed. On the other hand and in order to underline the performance of the proposed approach, a comparison in terms of computational complexity of the two algorithms has been done and it has proved that the complexity of B-OMP is in the order of only O(KN p N t L) while the complexity of AOMP is equal to O(KN p N t UL) so the AOMP requires N t more iteration to recover the estimated signal.
Focal Points and Salient Solutions

This chapter examines the ways in which negotiators might tighten and usefully apply the concept of focal points. Discussing a wealth of practical examples, it highlights two primary applications of focal points in negotiations: (1) their role in framing and reframing the issue(s) and thereby in the shaping of the negotiation, and (2) their role in facilitating concession and compensation. The authors exhibit the practical importance of focal points by demonstrating the utility of focal points in streamlining multi-party, multi-issue negotiations. They conclude that both negotiators and mediators stand to benefit from a thorough knowledge of the ways focality functions and the manner focal points can be used to facilitate or manipulate the successful outcome of negotiations.
Investigating child self-report capacity: a systematic review and utility analysis

To identify and evaluate methods for assessing pediatric patient-reported outcome (PRO) data quality at the individual level. We conducted a systematic literature review to identify methods for detecting invalid responses to PRO measures. Eight data quality indicators were applied to child-report data collected from 1780 children ages 8–11 years. We grouped children with similar data quality patterns and tested for between-group differences in factors hypothesized to influence self-report capacity. We identified 126 articles that described 494 instances in which special measures or statistical techniques were applied to evaluate data quality at the individual level. We identified 22 data quality indicator subtypes: 9 direct methods (require administration of special items) and 13 archival techniques (statistical procedures applied to PRO data post hoc). Application of archival techniques to child-report PRO data revealed 3 distinct patterns (or classes) of the data quality indicators. Compared to class 1 (56%), classes 2 (36%) and 3 (8%) had greater variation in their PRO item responses. Three archival indicators were especially useful for differentiating plausible item response variation (class 2) from statistically unlikely response patterns (class 3). Neurodevelopmental conditions, which are associated with a range of cognitive processing challenges, were more common among children in class 3. A multi-indicator approach is needed to identify invalid PRO responses. Once identified, assessment environments and measurement tools should be adapted to best support these individuals’ self-report capacity. Individual-level data quality indicators can be used to gauge the effectiveness of these accommodations.
Acoustic Side Channel Attack Against DNA Synthesis Machines: Poster Abstract

Synthetic DNA molecules play an essential role in genomics research and are a promising, high-capacity data storage medium. Currently, researchers use automated DNA synthesizers to custom-build sequences of oligonucleotides (short DNA strands) using the nucleobases: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T). Research laboratories invest large amounts of capital to engineer unique oligonucleotide sequences. In our work, we demonstrate the vulnerability of commonly used DNA synthesizers to acoustic side-channel attacks, where confidentiality can be breached to steal precious DNA sequences. We introduce a novel methodology to reverse engineer the acoustic noise generated by the DNA synthesizer and extract the type and order of the nucleobases delivered to the output. To the best of our knowledge, this is the first work which highlights the possibility of physical-to-cyber attacks in DNA synthesis technologies.
When Constant in a Proportional Relationship Isn’t Constant—A Sign of Not-So-Shared Understandings

Teacher knowledge, especially of proportional reasoning, is important, particularly in middle school grades in the United States. In this instrumental case study, one teacher’s understanding of con...
Persistent Tenosynovitis, Steroid Dependency and a Hyperpigmented Scaly Macular Rash in a Child With Juvenile Idiopathic Arthritis.

Blau syndrome is a rare autoinflammatory disease, characterized by granulomatous symmetric arthritis, skin rash and uveitis. It is caused by mutations in the CARD15/NOD2 gene, which is a significant part of innate immunity. We describe the case of a patient with Blau syndrome, initially misdiagnosed as juvenile idiopathic arthritis. Genetic analysis showed R334Q mutation in the NOD2 gene that is known to be linked to Blau syndrome. Our patient was successfully treated with the IL-1β blocking agent canakinumab, with clinical and laboratory remission without any adverse effects. To our knowledge this is one of the rare cases of Blau syndrome successfully treated with canakinumab. After moving abroad, canakinumab was discontinued and she was treated with adalimumab instead. Change in her treatment resulted in a relapse of her disease. Prompt recognition of Blau syndrome and the optimal treatment, are vital for the prevention of severe sequelae such as vision loss and joint deformities. Canakinumab constitutes a promising therapeutic approach for Blau syndrome and requires further investigation.
536. HIV Patients with COVID-19 in the Bronx: A Retrospective Cohort Study

Background: Since the start of the pandemic there has been limited data on mortality in people living with HIV (PLWH) who have Coronavirus Disease 2019 (COVID-19) in the United States (US) We conducted a retrospective review to investigate potential risk factors associated with survival and need for medical ventilation for PLWH and COVID-19 Methods: This is a retrospective observational cohort from a large academic center across three campuses, conducted from January 1, 2020 to April 30, 2020 Thirty day readmissions were observed from January 1, 2020 to May 31, 2020 Our patients were identified by an ICD-10 code (B20) corresponding to HIV and positive SARSCoV- 2 PCR test As a primary endpoint, we compared survivors vs non-survivors As a secondary endpoint, we compared patients who needed mechanical ventilator (MV) vs those who did not need MV Results: Seventy two PLWH (28 female patients (39%), median [IQR] age was 62 [-/+16] years) had positive SARS-CoV-2 PCR tests during this retrospective review Median CD4+ count was 235 cells/ul and 11 (15%) had an HIV viral load >200 copies/ mL The median length of stay was 5 days and 6 patients were directly discharged from the emergency department Ten patients were readmitted within 30 days with SARSCoV- 2 - like symptoms and 2 are still inpatient Twenty patients (27 8%) have expired All non-survivors that expired had an undetectable HIV viral load (0%, p=0 02) The 11 patients with unsuppressed HIV viral loads at the start of the study period all survived, p=0 02 Non-survivors were more likely to have chronic kidney disease CKD (p< 0 01) acute kidney injury (p< 0 01), higher absolute neutrophils (p< 0 01), and elevated IL-6 levels (p< 0 01) compared to survivors Fifteen patients (20 8%) required mechanical ventilation (MV), 3 (4 1%) of those patients survived Patients that required MV were more likely to be male (p=0 01) obese (p< 0 01) and had higher absolute neutrophil counts (p=0 01) versus those that did not need MV Patients with lower CD4 counts (< 200 cells/uL) did not require more mechanical ventilation (p=0 04) Conclusion: PLWH who had COVID-19 had a high mortality rate Since all the patients who died had an undetectable HIV viral load across CD4 counts, our study suggests that patients with uncontrolled HIV are not at an increased risk of mortality
Short-Term Internationally Mobile Academics and Their Research Collaborations Upon Return: Insights From the Fulbright U.S. Scholar Program:

The international mobility of academics is one of the key mechanisms through which university internationalization occurs; yet, fewer studies have investigated the impact that it has on academics’ ...
Neural network image fusion with PCA preprocessing

The fusion of multispectral sensor data techniques for sets containing complementary information about the subject of observation leads to the visualization of data into a form more easily interpreted by both humans and algorithms. Many applications of feature-level fusion seek to combine edges and textures, across the bandwidth of the sensory spectrum. Visualization techniques can be skewed by the introduction of corruption and redundancies induced by harmonics. A majority of image fusion techniques rely on intensity hue saturation (IHS) transforms, principal component analysis (PCA), and Gram Schmidt. PCA’s ability to remove the redundancy from a set of correlated data while preserving the variance and its resistance to color distortion lends itself to this application. PCA also has a lower spectral distortion as compared to IHS and has been found to create superior image fusion. The application of neural network control techniques has been shown to more accurately recreate results similar to those found by human inference. Over the years, increased computation power has given rise to the spread of neural networks into roles previously carried out by humans. Select advanced image processing techniques have benefited greatly from their implementation. We propose a novel method of utilizing PCA in conjunction with a neural network to achieve a higher quality of image fusion. Implementation of an autoencoder neural network to fuse this information creates a higher level of data visualization when compared to traditional weighted fusion techniques.
Calculation of maximum entropy densities with application to income distribution

The maximum entropy approach is a flexible and powerful tool for density approximation. This paper proposes a sequential updating method to calculate the maximum entropy density subject to known moment constraints. Instead of imposing the moment constraints simultaneously, the sequential updating method incorporates the moment constraints into the calculation from lower to higher moments and updates the density estimates sequentially. The proposed method is employed to approximate the size distribution of U.S. family income. Empirical evidence demonstrates the efficiency of this method.
Spinal Cord Tumors

Spinal cord tumors are a wide spectrum tumor based on histology and anatomical location. The tumors can be classified based on imaging into extradural, intradural–extramedullary, or intramedullary. The standard approach for management is complete en bloc excision with neuronavigational techniques including intraoperative ultrasonography and neurophysiologic monitoring. The need for adjuvant radiation depends upon grade, extent of disease and progression of disease after surgical resection. There is no clear role of chemotherapy in spinal cord tumors.
Tactile motion coordinate transforms in the somatosensory system

Our ability to perceive motion information on the skin is key to manipulating dynamic objects in the environment. Previous studies show that the brain derives tactile motion representations by integrating local cues of the object that impinge on the skin (e.g., speed, intensity, direction), a mechanism known as the Full Vector Average model [1]. This model was derived from studies that placed the hand in the same posture. Yet, object perception and manipulation with the hand (i.e., haptics) is a highly dynamic and goal-directed function. Thus, it is key to study whether tactile motion perception is transformed by hand position, and whether these transformations depend on the reference frame in which the motion judgement is made. Here, we asked human participants to discriminate motion stimuli on the index finger in two reference frames (hand- centric vs. sternum-centric), with the hand placed in different positions. We found that human observers can systematically represent tactile motion under explicitly instructed reference frames. We further showed that tactile motion discriminations can be accurately decoded using a Bayesian generative model.
Design Of High-Reflectivity Supermirror Structures

We present a new method of designing supermirrors, based on considering the contribution of each bilayer to the extinction in a given stack of bilayers, and derive and solve the discrete equations governing the choice of layer thicknesses. In the limit of zero layer thickness, the usual continuum result is recovered. The design, which can produce essentially perfect reflectivity over the entire supermirror range, also provides an objective physical mechanism for trading reflectivity to gain angular range.
This Is Water Revisited: Creativity Lost.

Laura Roberts, in her essay “Water Pie: Creativity and Leadership in Academic Psychiatry” [1], worries about the state of modern psychiatry, medicine, and real threats to creativity. Should we be worried? Definitely! But before considering the forces surrounding us that thwart creative thinking, let us look at the foundation for creative process. Creativity is the essence of new discovery—in science, the arts, humanities, medicine, economics, politics, and virtually every field. As Andreasen and Ramchandran [2] point out, “The capacity to be creative is one of the most important characteristics that human beings possess” (p. 49). The inception of virtually every revolutionary scientific theory derived from creative thinking and astute observations, most of the time combined. If not for thinking outside the box, outside the constraints of accepted principles, our greatest discoveries would be lost. Consider germ theory, relativity theory, the theory of evolution, quantum theory, theories on environmental causes of cancer, attachment theory, psychoanalysis, modern psychopharmacology, and, most recently, advances in genetics and epigenetics—these and many other epic conceptual frameworks would never have surfaced. As the preponderance of scientists tell us, first the concept and theory and then the proof. Many visionaries, fromNicolausCopernicus, GalileoGalilei, Sigmund Freud, Leonardo da Vinci, and Benjamin Franklin to Albert Einstein, risked and lived through ridicule. They questioned commonly accepted theories and proposed alternatives. As Thomas Kuhn reminds us in The Structure of Scientific Revolutions [3], all scientific theories are self-contained. Any data that defy consistency within the confines and framework of theory are thrown out as recalcitrant [3]. Further, Willard van Orman Quine [4], a modern pragmatist philosopher, argues that there is indeterminacy of translation from one theory to another—evidence alone does not dictate scientific theory. Scientific theories are by nature constructs and have internal consistency and elegance. They are “true” but only relative to a context. Take Newtonian physics. It just does not work when particles are traveling close to the speed of light. Then, the theory of relativity takes over as an explanatory framework. Einstein’s creative imagination led him to move beyond an accepted and validated theoretical model and create an entirely different one. He did not passively take the current model for granted but actively considered alternatives. He asked different questions. It takes the freedom to question accepted principles to go beyond accepted views and standards. Although all theories require “proof,” they begin and end as a creative process. And we know that this was the way the theory of relativity evolved.
3D kinetic alpha complexes and their implementation

Motivated by an application in cell biology, we describe an extension of the kinetic data structures framework from Delaunay triangulations to fixed-radius alpha complexes. Our algorithm is implemented using Cgal, following the exact geometric computation paradigm. We report on several techniques to accelerate the computation that turn our implementation applicable to the underlying biological problem.
Orthogonal Positive-Bevel Termination for Chip-Size SiC Reverse Blocking Devices

Symmetric blocking power semiconductor switches require positive-bevel edge terminations for the reverse blocking p-n junction. This technique has been extensively applied to silicon wafer-size devices with high current ratings. In this letter, we propose and experimentally demonstrate, for the first time, that an orthogonal positive-bevel termination can be used for the reverse blocking junction of chip-size SiC devices. The edge termination was formed by sawing the SiC wafer with a V-shaped dicing blade. For proof of concept, our experiment was done on a SiC wafer with a 15.8-μm 6.1 × 1015 cm-3 p-type epitaxial layer grown on an N+ substrate. The positive-bevel termination resulted in a breakdown voltage of over 1000 V as limited by reach-through breakdown even without removal of damage from the sawing. The leakage current was found to be reduced by two orders of magnitude after reactive ion etching of the SiC bevel surface to remove the sawing damage.
Characterization of acute kidney injury in hospitalized dogs and evaluation of a veterinary acute kidney injury staging system

Objective To retrospectively apply standards characterizing acute kidney injury (AKI) used in human medicine to a population of critically ill hospitalized dogs in order to identify dogs with potential AKI based on subtle increases in plasma creatinine concentration. Design Retrospective study. Setting University Veterinary Medical Teaching Hospital. Animals One hundred and sixty-four client-owned dogs admitted to the intensive care unit. Interventions None. Measurements and Main Results Medical records of 164 dogs meeting the study inclusion criteria were reviewed to identify age, results of creatinine measurements, discharge status, length of stay, performance of general anesthesia, number of diagnoses, and calculated survival prediction index scores (SPI2). A veterinary AKI (VAKI) staging system was retrospectively applied to classify dogs based on increase in creatinine concentration from baseline as follows: stage 0 (S0; <150%), stage 1 (S1; 150–199% or ≥26.5 μmol/L [≥0.3 mg/dL]), stage 2 (S2; 200–299%), or stage 3 (S3; ≥300%). Of the dogs evaluated, 140/164 were VAKI stage S0, 19/164 were classified as S1, 3/164 as S2, and 2/164 were S3. Mortality rate was greater for S1–3 (13/24; 54.2%) compared to S0 dogs (22/140; 15.7%) (P < 0.0001). Length of stay, general anesthesia, and number of diagnoses were not associated with survival. In a logistic regression model, stage and age were jointly, significantly associated with mortality (P = 0.0002 and P = 0.0330, respectively). Mean SPI2 scores were not different between S0 (0.52) and S1 (0.59) dogs (P = 0.23). Only 4/19 (21%) of S1 dogs had a peak plasma creatinine concentration above the laboratory reference interval. Conclusions Dogs meeting VAKI stage 1–3 criteria were less likely to survive to discharge. Small increases in plasma creatinine concentration may be clinically relevant even when absolute values are within reference intervals.
Serodiagnosis in early Lyme disease.

Using a commercially available enzyme-linked immunosorbent assay (ELISA) and an immunoblot assay (IB), we tested sera from 100 patients with erythema migrans (EM) seen in 1991 a the Westchester County Medical Center Lyme Disease Diagnostic Center. Convalescent-phase sera were available from 59 patients. Fifty-five patients had EM of 14 days' duration. During the acute phase of infection, 35 patients had a positive ELISA result and 43 had a positive IB result by the recently published criteria of Dressler et al. (F. Dressler, J. A. Whalen, B. N. Reinhardt, and A. C. Steere, J. Infect. Dis. 167:392-400, 1993) for interpretation of IB in patients with Lyme disease. A greater sensitivity of IB was observed in patients with EM of 14 days' duration were reactive by both tests, as follows: 13 positive and 1 equivocal by ELISA and 12 positive and 2 indeterminate by the IB. The band reactivity most frequently observed in the IB was to the 41- and 25-kDa antigens, the latter being the most frequent band observed in immunoglobulin M blots. Seroconversion was observed in 74 and 64% of evaluable patients by ELISA and IB, respectively, despite the use of antibiotic therapy.
Mechanisms to Meet/Beat Analyst Earnings Expectations in the Pre- and Post-Sarbanes-Oxley Eras

This paper asks two questions. First, has the prevalence of expectations management tomeet/beat analyst expectations changed in the aftermath of the 2001-2002 accountingscandals and the passage of the 2002 Sarbanes-Oxley Act (SOX)? Second, has the mixamong the three mechanisms used for meeting earnings targets: accrual earningsmanagement, real earnings management, and earnings expectations management shiftedin the Post-SOX Period? We document that the propensity to meet/beat analyst expectations has declined significantly in the Post-SOX Period. Our primary findings explain this pattern. In particular, we find a decline in the use of expectations management and accrual management, and no change in real earnings management in the Post-SOX Period relative to the preceding seven-year period. Our results are robust to controlling for varying macro economic conditions. These findings contribute to the academic literature, investors, and regulators.
The distribution of sister chromatids at mitosis in Chinese hamster cells.

The recent demonstration by Rosenberger and Kessell (1968) that chromatids segregate non-randomly in yeast, has again raised questions about the randomness of chromatid segregation in higher organisms. Autoradiographic studies of synchronized Chinese hamster cells show that at the second anaphase after labeling the chromatids segregate in a completely random manner.
Fracture toughness of a high carbon and high silicon steel

Abstract A high carbon and high silicon (HCHS) steel containing about 1% carbon and 2.5% silicon has been developed. This steel has been synthesized using concepts from austempered ductile cast iron (ADI) technology. The influence of austempering temperature on the microstructure and the mechanical properties of this steel in room temperature and ambient atmosphere was examined. The influence of microstructure on the plane strain fracture toughness of this HCHS steel was also investigated. Compact tension and round cylindrical specimens were prepared from this steel. These specimens were then austenitized at 927°C for 2 h and then austempered at several temperatures between 260 and 399°C for a fixed time period of 2 h to produce different microstructures. The microstructures were characterized by X-ray diffraction and optical metallography and correlated to the mechanical properties. The test results showed that the maximum fracture toughness is obtained in this steel with a upper bainitic microstructure when the microstructure contains about 35% austenite and the carbon content in the austenite is about 2%. The retained austenite and its carbon contents increased with austempering temperature, reaching a peak value at 385°C and then retained austenite decreased with increasing temperature. The carbon content of the austenite also showed a similar behavior. The fracture toughness was found to depend on the parameter (XγCγ/d)1/2 where Xγ is the volume fraction of the austenite, Cγ is the carbon content of austenite and d is the mean free path of dislocation motion in ferrite.
The comparative psychology of communication: the issue of grammar and meaning.

I read Dr. Lockard's very interesting comment on comparative psychology, I and was impressed not only with the scholarship he showed in it, but also by the fact that he feels comparative psychology has poduced mostly what in comparative anatomy and comparative physiology we call analogy, rather than homology. I agree, and have therefore developed an aversion to comparative psychology as it is generally practiced. I am by choice a physiological psychologist, because I believe that only through the study of mechanism can we achieve insight into homology. In the language of genetics, only through an analysis of mechanism can we penetrate through the phenotypical to the genotype. Pure description of animal behavior, though fascinating, is not enough. I used to go out with Danny Lehrman and others to watch birds, and I find watching primates even more interesting. Watching people can of course be the epitome of fascination. But for me these observational techniques have no real chewiness to them, no earthiness. I have to participate, to know about mechanisms, before I can be really satisfied. Most comparative psychologists use Darwinism as an excuse to make their observations a science. To quote Sigmund Freud, 2 this "has .. a dubious appearance of arbitrariness, even though it would be possible, pursuing a Darwinian line of thought to claim that ... [these mechanisms] are indispensible and consequently bound to survive." Now I don't mean by this that genetic population pressure studies or the pursuit of the machinery of evolution is to be regarded as trivial. What I am talking about is the oft-repeated, simple assertion that observations can be explained "by recourse to the principles of random variation and special selection," without spelling out the mechanism by which those principles come to apply to the particular behavior observed. Some have, of course, done the job properly. Danny Lehrman, Thorpe, Hinde, and the whole Cambridge group: these are people who have combined evolutionary principles with the search for mechanisms. So, in the tradition of these pioneers, let me illustrate how I apply the comparative method. I will address myself to the problem of grammar and meaning. I have deliberately chosen this difficult topic; there is no reason why our science should so utterly disregard cognitive processes as it has to date. Konrad Lorenz has said, shOWing great insight, "Life is a knowledge process." In his address of acceptance of the chair at Edinburgh in 1970 and also elsewhere, Vowles ,2 7 suggested that perhaps phylogeny could be characterized by the development of a grammar of behavior. Invertebrates show finite-state Markov-type constructions; vertebrates show phrase-structure hierarchies; and
Computer simulation of gas generation and transport in landfills. III: Development of lanfills' optimal model

Abstract In Parts I and II of this series a 3D model was developed for transport and reaction of gaseous mixtures in landfills, and was utilized, through computer simulations, to investigate the effect of various factors on the gases’ concentrations and the landfill's total pressure, under quasi-steady state and dynamic conditions. A fundamental problem with modelling of landfills is the severe shortage of publicly available experimental data for their static and dynamical properties, which hinders the development of accurate models for them. In the present paper we address this problem by formulating it as one of optimization, whereby the optimal spatial distributions of the porosity, permeability, tortuosity factor, and the total potential of various types of wastes for producing the gases in a landfill are determined, given some limited experimental data for a property of the landfill, such as the amount of methane which is extracted from it over a period of time. The numerical simulator developed previously is coupled to the Genetic algorithm in order to optimize the parameter space that characterizes the landfill's morphology and the reaction properties of the wastes. Since the parameter space can be very large, containing thousands of parameters to be optimized, we utilize massively parallel computations with message-passing interface technique in order to develop the optimal model. It is shown that, not only does the optimization technique reproduce accurately the data based on which the optimal model is developed, but also provides accurate predictions for the future behavior of the landfill's properties.
THE EFFECT OF UNILATERAL ULTRAVIOLET LIGHT ON THE DEVELOPMENT OF THE FUCUS EGG

1. When Fucus eggs which have been fertilized for a sufficient length of time are irradiated unilaterally with monochromatic ultraviolet light (λ2804 A) of adequate dosage, 97–100 per cent form rhizoids on the halves of the eggs away from the source of radiation (see Figs. 1 and 2). 2. The responsiveness of the eggs increases gradually after fertilization and does not reach a maximum until about 7 hours at 15°C. (see Fig. 3). The first rhizoids begin to form in a population at about 12 hours after fertilization. The responsiveness remains maximal until at least 11 hours after fertilization. 3. It is suggested that the low responsiveness of a population of eggs at an earlier period is due to recovery from the effects of irradiation before the rhizoids begin to form. 4. The response of eggs to λ2804 A is proportional, over a wide range, to the logarithm of the dosage (see Fig. 1). Dosage was regulated by the duration of exposure during the period of maximum response. 5. High dosages of λ2804 A, of the order of 10,000 ergs per mm.2, cause the rhizoids to form fairly precisely away from the source of radiation (see Fig. 2). Twice this dosage inhibits rhizoid formation altogether without causing cytolysis. 6. Other wave-lengths which have also been shown to be effective are: 3660, 3130, 2654, 2537, 2482, and 2345 A. Only exploratory measurements have been made to test the effectiveness of these wave-lengths, but they show that much greater energy is necessary to obtain a strong response with λ3130 and 3660 A, especially the latter. The wave-lengths shorter than 2804 A, on the other hand, show the same order of effectiveness as λ2804 A. Some may be more effective. 7. A beam of λ2804 A which is incident on a single layer of Fucus eggs is completely extinguished at 2, 3, 6, or 6½ hours after fertilization. About 85 per cent of a beam of λ3660 A is extinguished. The wave-length 3660 A is thus not so completely absorbed as λ2804 A, but the difference in proportion absorbed by the egg is not nearly so great as the difference in effectiveness.
Read-noise considerations in cryoelectric memory systems

Several sources of deterministic read noise in cryo-electric memories are discussed. Write noise and random thermal noise are not included. Noise on a single plane is first considered. Inductively coupled in-mode noise can be minimized by crossing lines at right angles and maintaining maximum distance between parallel segments of drive and sense lines. Capacitively coupled in-mode noise can be minimized by go-and-return layout. Common-mode noise is analyzed with the aid of a useful model. In-mode noise and common-mode to in-mode conversion for stacks of memory planes in simple system organizations are considered next. Reduction of these noise factors is achieved by the use of go-and-return connections of drive and sense lines between planes. Proper system operation requires a minimization of all deterministic noise components discussed.
Functional characterization of a Drosophila mitochondrial uncoupling protein.

Sequence alignment of conserved signature motifs predicts the existence of the uncoupling protein 5 (UCP5)/brain mitochondrial carrier protein (BMCP1) homologue in Drosophila melanogaster (Hanak P. and Jezek P. (2001). FEBS Lett.495, pp. 137–141.). Here we demonstrate the functional characterization of the Drosophila melanogaster UCP5 protein (DmUCP5) in the heterologous yeast system, the first insect UCP reported to date. We show that physiological levels of DmUCP5 expression are responsible for an increase in state 4 respiration rates and a decrease in mitochondrial membrane potential. Furthermore, similar to UCP1, UCP2, and UCP3, the uncoupling activity of DmUCP5 is augmented by fatty acids and inhibited by the purine nucleotide GDP. Thus, DmUCP5 shares the mechanisms known to regulate the UCPs characterized to date. A lack of growth inhibition observed in DmUCP5 expressing yeast is consistent with the notion that physiological uncoupling has a minimal effect on cell growth. Finally, semiquantitative RT-PCR analysis shows a distinctive pattern of DmUCP5 expression predominantly localized in the adult head, similar to the expression pattern of its mammalian homologues. The conserved regulation of the expression of this gene from mammals to fruit flies suggests a role for UCP5 in the brain.
Msx2 Is a Transcriptional Regulator in the BMP4-Mediated Programmed Cell Death Pathway

Homeobox-containing genes play an important role in patterning processes that occur during embryogenesis. Programmed cell death is a key process during pattern formation. The mechanisms by which programmed cell death is spatially regulated are not well characterized. Msx1 and Msx2 are two closely related homeobox-containing genes that are expressed at sites where cellular proliferation and programmed cell death occur, including the developing limb and the cephalic neural crest. Tissue interactions are necessary for the maintenance of Msx1 and Msx2 expression and programmed cell death. It has been demonstrated that BMP4 can regulate cell death at these same sites as well as induce Msx expression. These observations lead to the hypothesis that Msx2 is a key regulator of cell death in the BMP-mediated pathway. Embryonic stem cell lines will undergo processes typical of early embryogenesis upon aggregation and have recently been shown to provide a model system for programmed cell death. In contrast to ES cells, we see that P19 cells do not undergo pronounced cell death upon aggregation; however, constitutive ectopic Msx2 expression in P19 cells results in a marked increase in apoptosis induced upon aggregation but has no effect when cells are grown as a monolayer. If aggregates are allowed to interact with a substrate, the process of programmed cell death is completely inhibited. Addition of BMP4 to aggregated P19 cells also results in cell death; however, BMP4 does not increase levels of cell death in Msx2-expressing cells. Addition of BMP4 to P19 cells results in an induction of Msx2 transcription consistent with its proposed role in cell death in the embryo. Our data support a model by which BMP4 induces programmed cell death via an Msx2-mediated pathway and provide direct functional evidence that Msx2 expression is a regulator of this process.
Further Evidence that Human Acellular Dermal Matrix Decreases Inflammatory Markers of Capsule Formation in Implant-Based Breast Reconstruction

Background Human acellular dermal matrix (HADM; previously termed “acellular cadaveric dermis”) may limit inflammatory changes believed to play a role in capsular contracture, a common complication of implant-based breast reconstruction. Objectives Differences between HADM and native breast capsule specimens were evaluated by immunohistochemical analysis of key inflammatory markers involved in capsule formation. Methods Twenty consecutive patients underwent immediate, 2-stage, implant-based breast reconstruction with dual-plane HADM. During tissue expander–implant exchange, full-thickness biopsies of biointegrated HADM and native breast capsule (internal control) from the tissue-expander envelope were obtained. Immunohistochemical analysis was performed for endothelial cells (CD31), B cells (CD20), T cells (CD3), macrophages (CD68), collagen I and III, and myofibroblasts (α-smooth muscle actin). Observed levels of marker labeling were semiquantitatively scored from 0 (none) to 3 (severe) by a blinded histopathologist and were statistically analyzed with the Wilcoxon rank sum test. Results A bilateral sample was obtained from 1 patient; all other samples were unilateral. Compared with capsule samples from native breast tissue, HADM samples had significantly lower levels of all inflammatory markers ( P < .001). Conclusions These lower levels of inflammatory markers support previous evidence that HADM may inhibit inflammatory and profibrotic signaling characteristics of breast capsule development and decrease the risk of capsular contracture. Further investigation is needed to determine the mechanism by which HADM inhibits these inflammatory cells, whether HADM reduces the incidence of breast capsular contracture, and if so, the longevity of this effect. Level of Evidence: 3 ![Graphic][1] Therapeutic [1]: /embed/inline-graphic-1.gif