cssi/SciSciGPT-SciSciNet huggingface dataset:
Covalent Small Ubiquitin-like Modifier (SUMO) Modification of Maf1 Protein Controls RNA Polymerase III-dependent Transcription Repression

RNA polymerase (pol) III transcribes genes that determine biosynthetic capacity. Induction of these genes is required for oncogenic transformation. The transcriptional repressor, Maf1, plays a central role in the repression of these and other genes that promote oncogenesis. Our studies identify an important new role for SUMOylation in repressing RNA pol III-dependent transcription. We show that a key mechanism by which this occurs is through small ubiquitin-like modifier (SUMO) modification of Maf1 by both SUMO1 and SUMO2. Mutation of each lysine residue revealed that Lys-35 is the major SUMOylation site on Maf1 and that the deSUMOylase, SENP1, is responsible for controlling Maf1K35 SUMOylation. SUMOylation of Maf1 is unaffected by rapamycin inhibition of mammalian target of rapamycin (mTOR) and mTOR-dependent Maf1 phosphorylation. By preventing SUMOylation at Lys-35, Maf1 is impaired in its ability to both repress transcription and suppress colony growth. Although SUMOylation does not alter Maf1 subcellular localization, Maf1K35R is defective in its ability to associate with RNA pol III. This impairs Maf1 recruitment to tRNA gene promoters and its ability to facilitate the dissociation of RNA pol III from these promoters. These studies identify a novel role for SUMOylation in controlling Maf1 and RNA pol III-mediated transcription. Given the emerging roles of SENP1, Maf1, and RNA pol III transcription in oncogenesis, our studies support the idea that deSUMOylation of Maf1 and induction of its gene targets play a critical role in cancer development.
Bioinorganic chemistry: Bond breaking bacteria-style.

Chemists envy the ease with which some bacterial enzymes can break carbon–hydrogen bonds. They now imitate the enzyme active site in an oxo-bridged diiron compound that can cleave these strong bonds.
CSF cytology has limited value in the evaluation of patients with ependymoma who have MRI evidence of metastasis.

Purpose To investigate the usefulness of cerebrospinal fluid (CSF) cytology in pediatric patients with ependymoma who relapsed after focal irradiation. Methods Eighty-eight patients with ependymoma received conformal radiotherapy (CRT) from July 1997 through January 2003 on an IRB approved prospective treatment protocol. CSF cytology results from evaluations performed prior to CRT and at the time of failure were reviewed for patients who progressed after CRT as documented by magnetic resonance imaging (MRI). Results Twenty-two patients had MRI documented evidence of progression after CRT. Ten patients developed distant failure without local failure, four had combined local and distant failure and eight had local failure without distant failure. The median time from the start of CRT to progression was 19 months (range: 6–73). CSF cytology at diagnosis was negative for the presence of malignant cells in all patients. At the time of progression, CSF cytology was performed in 16 of 22 patients including all 10 patients with distant failure without local recurrence. Malignant cells were not found in any of the evaluated CSF specimens including those with distant failure documented by MRI. Conclusions CSF cytology does not add valuable information when evaluating patients with ependymoma who have evidence of distant failure documented by MRI. The usefulness of CSF cytology in the general follow-up evaluation of pediatric patients with ependymoma remains uncertain. © 2005 Wiley-Liss, Inc.
Exploring Acidic Functionalities in the Design and Development of High Performance 193nm Photoresist Polymers

The combination of immersion lithography and reticle enhancement techniques (RETs) has extended 193nm lithography into the 45nm node and possibly beyond. In order to fulfill the tight pitch and small critical dimension requirements of these future technology nodes, the performance of 193nm resist materials needs to further improve. In this paper, we have systematically studied a variety of acidic functionalities in an effort to improve the dissolution properties of 193nm resists. The hexafluoroalcohol (HFA) and fluorosulfonamide (FSM) are found to be most effective in eliminating the swelling behavior associated with typical 193nm methacrylate resists. The HFA and FSM groups are highly transparent at 193nm. High performance 193nm resists are developed with the HFA and FSM acidic groups. Compared to the HFA group, the trifluoromethyl sulfonamide (TFSM) functionality has a lower pKa value and contains less fluorine atoms. Polymers containing the TFSM functionality have exhibited improved dissolution properties and better etch resistance than their HFA counterparts. Resists based on the FSM-containing polymers have shown superior lithographic performance for line, trench and contact hole levels under the 45nm node exposure conditions. In addition, FSM resists have also demonstrated excellent bright field and dark field compatibility and thereby make it possible to use one resist for both bright field and dark field level applications. Finally, to alleviate the adverse impact of the fluorine content in the etch resistance of the 193nm resists, we have also evaluated a non-fluorinated acidic functional alternative-naphthol.
The method of fractional steps for conservation laws

The stability, accuracy, and convergence of the basic fractional step algorithms are analyzed when these algorithms are used to compute discontinuous solutions of scalar conservation laws. In particular, it is proved that both first order splitting and Strang splitting algorithms always converge to the unique weak solution satisfying the entropy condition. Examples of discontinuous solutions are presented where both Strang-type splitting algorithms are only first order accurate but one of the standard first order algorithms is infinite order accurate. Various aspects of the accuracy, convergence, and correct entropy production are also studied when each split step is discretized via monotone schemes, Lax-Wendroff schemes, and the Glimm scheme.
Borrowed reserves and deposit variation: The risks to monetary policy

A theory of bank reserves is presented with emphasis on the behavior of borrowed reserves, the Federal Reserve's operating instrument. The theory explains the observed nonlinear relationship between borrowing and the spread between the federal funds rate and the discount rate. The theory shows that borrowed reserves are also a function of deposit variation. A shift in bankers' perceptions of deposit variation can cause borrowed reserves demand to shift so that the level of borrowing is not a reliable indicator of the degree of reserve pressure. Since borrowed reserves are used as the Federal Reserve's operating instrument, problems such as these pose substantial risks to the implementation of monetary policy.
Requirement of Gαi in thymic homing and early T cell development

Demonstration of thymic homing dependent on Galphai proteins is one of the keys to determine whether thymic entrance of blood-borne progenitors is a highly selective process. The present study provides compelling evidence of an indispensable role for Galphai proteins in this process. Absence of either Galphai2 or Galphai3 significantly abrogated thymic homing, with an effect of Galphai3 being greater than that of Galphai2. Pertussis toxin treatment that blocks both Galphai2 and Galphai3 almost completely blocked thymic seeding in the thymus. Null mutation of Galphai3 also hindered bone marrow cell development and thus reduced production of pre-thymic progenitors. In contrast, Galphai2 exhibited a more prominent role than Galphai3 in guidance of CD4-CD8--double negative (DN) 1 cell migration and early thymic differentiation. The Galphai-deficiency-induced defects might be compensated for in part via augmented function of thymic stromal cells so that a nearly normal output of mature T cells could be maintained in these Galphai-deficient mice. These studies underscore the importance of Galphai in regulating thymic homing and pre-thymic and early thymocyte differentiation.
Group index and group velocity dispersion in silicon-on-insulator photonic wires

We determine group index and group velocity dispersion (GVD) of SOI single-mode strip waveguides (photonic wires) with 525x226nm cross-section over the entire telecommunication bandwidth by employing an integrated Mach-Zehnder interferometer. The measured GVD yields 4400 ps/(nm*km) at 1550 nm and exceeds that of standard single-mode fibers by almost three orders of magnitude. In the photonic wires the GVD is mainly determined by strong light confinement rather than by material dispersion. Our results indicate that despite this high GVD, dispersion-induced signal impairment is negligible in photonic circuits for data rates up to 100-Gb/s and total waveguide lengths as long as about 1 meter. The measured group index and GVD are used as benchmarks to compare model calculations originating from four different theoretical methods.
Polarizabilities and local field estimates for ten oxides from refractive-index measurements on doped films.

By using accurate prism-coupled optical waveguide refractive-index measurements on cation-doped indium oxide films and a classical polarizability model having adjustable local field weighting factors, estimates have been obtained for the electronic polarizabilities of ten cations and the relative local fields in their respective oxides. Self-consistent results for the ten oxides were obtained for a constant oxygen polarizability of 1.5 (A)3. The relative local fields were found to be larger at the oxygen than at the cation sites, consistent with the observation that the refractive index is more sensitive to anion than cation changes. The results should be useful for optical applications requiring dopant control of refractive index (e.g., for antireflection coatings and optical waveguides).
Clinical Determinants of Radiation Dose in Percutaneous Coronary Interventional Procedures: Influence of Patient Size, Procedure Complexity, and Performing Physician

Objectives The objectives of this work were to establish the primary clinical determinants of patient radiation dose associated with percutaneous coronary interventional (PCI) and to identify opportunities for dose reduction. Background Use of X-ray imaging and associated radiation dose is a necessary part of PCI. Potential adverse consequences of radiation dose include skin radiation injury and predicted increase in lifetime cancer risk. Methods Cumulative skin dose (CSD) (measured in gray [Gy] units) was selected as a measurement of patient radiation burden. Several patient-, disease-, and treatment-related variables, including 15 performing physicians, were analyzed in a multiple linear regression statistical model with cumulative skin dose CSD as the primary end point. The model results provide an estimate of the relative CSD increase (decrease) attributable to each variable. Results Percutaneous coronary interventions performed on 1,287 male and 540 female patients were included. Median patient age was 68.6 years, median body mass index was 29.7 kg/m2, and median weight was 88 kg. Median CSD was 1.64 Gy per procedure for male and 1.15 Gy for female patients. Increasing body mass index, patient sex, lesion complexity, lesion location, and performing physician were significantly associated with CSD. Physicians who performed more procedures were associated with lower CSD. Conclusions Several primary determinants of patient radiation dose during PCI were identified. Along with physician development of radiation-sparing methods and skills, pre-procedure dose planning is proposed to help minimize radiation dose for PCI.
p53 regulates thymic Notch1 activation

Notch is crucial for multiple stages of T cell development, including the CD4+CD8+ double positive (DP)/CD8+ single positive (SP) transition, but regulation of Notchactivation is not well understood. p53 regulates Presenilin1 (PS1) expression, and PS1 cleaves Notch, releasing its intracellular domain (NIC), leading to the expression of downstream targets, e.g. the HES1 gene. We hypothesize that p53 regulates Notch activity during T cell development. We found that Notch1 expression and activation were negatively regulated by p53in several thymoma lines. Additionally, NIC was elevated in Trp53–/– thymocytes as compared to Trp53+/+ thymocytes. To determine if elevated Notch1 activation in Trp53–/– thymocytes had an effect on T cell development, CD4 and CD8 expression were analyzed. The CD4+ SP/CD8+ SP T cell ratio was decreased in Trp53–/– splenocytes and thymocytes. This alteration in T cell development correlated with the increased Notch1 activation observed in the absence of p53. These data indicate that p53 negatively regulates Notch1 activation during T cell development. Skewing of T cell development toward CD8+SP T cells in Trp53–/– mice is reminiscent of the phenotype of NIC-overexpressing mice. Thus, we suggest that p53 plays a role in T cell development, in part by regulating Notch1 activation.
Mechanisms of peptide hormone secretion.

According to the classical view, peptide hormones are stored in large dense-core vesicles that release all of their cargo rapidly and completely when they fuse with and flatten into the plasma membrane. However, recent imaging studies suggest that this view is too simple. Even after vesicles fuse with the plasma membrane, cells might control the rate of dispersal of vesicle cargo – either by modulating the properties of the fusion pore that connects the vesicle lumen to the extracellular solution or by storing cargo in states that disperse slowly in the extracellular space. Understanding these mechanisms is important, owing to the increasing prevalence of diseases, such as type 2 diabetes mellitus, which arise from insufficient secretion of peptide hormones.
Visual event related potentials after methylphenidate and sodium valproate in children with attention deficit hyperactivity disorder

We divided a group of Attention Deficit Hyperactivity Disorder (ADHD) boys into two groups determined by the results of EEG and visual ERP tests--those who had excessive EEG background slowing, EEG epileptiform activity or abnormally high amplitude ERP waves (the "E-ADD" group), and those with normal EEG and ERP (the "ADD" group). The subjects of each group were then given either a dose of methylphenidate (Ritalin, MPH), sodium valproate (Depakene, VPA) or placebo, and repeated visual ERPs one hour later. Following both medications there was a significant suppression of the amplitude of the N3, the "slow negative" wave of the ERP, in the E-ADD group but not in the ADD group. The effect of VPA and MPH in ADHD children may be related to the electrophysiological (EEG, ERP) background. Both medications may have a similar effect on arousal processes in ADHD.
Quantitative detection of E. coli O157:H7 eaeA gene using quantum dots and magnetic particles

A quantitative gene detection technique targeting the pathogenic E. coli O157:H7 eaeA gene was developed using magnetic bead (MB)-quantum dots (QDs) nanoparticle complexes. MBs allowed for the separation of DNA-conjugated QD nanoparticles via magnetic field manipulation. QDs provided internal fluorescence calibration to account for the intrinsically different numbers of nanoparticles interrogated in each assay. Based on the measurement of normalized fluorescence (Cy3/QD655), the linear quantification ranges of ssDNA and dsDNA targets were determined to be 10 through 103 fM (R2 = 0.992) and 2 × 102 through 6 × 107 gene copies (R2 = 0.972), with detection limits of 9.72 fM and 104 gene copies, respectively. The kinetic results indicate that adjustment of hybridization temperature in accordance to the amount of target DNA was required to maximize the efficiency of DNA hybridization. We were able to discriminate perfectly matched target DNA, 1-, 2-, and 41-base pair mismatched target DNAs in our approach and therefore demonstrated excellent selectivity. Our technique was also used on pure bacterial culture to showcase its ability to analyze environmental samples.
From software engineer to day trader in 3 easy steps: a comparison of software engineering (SE) data mining with financial data mining

One of the research objectives in Software Engineering Data Mining is to produce useful, usable, verifiable, and repeatable models for better managing software processes and projects. This objective implies that an organization will be more profitable as consequence of better management.Financial events, such as bailouts, high unemployment rates, foreclosures, etc. have received extensive news coverage since Fall, 2008. Many professionals are concerned about their job status and their retirement accounts. From the context of the Software Engineering community, one question arises: To what extent can the skills and knowledge attained in Software Engineering Data Mining apply towards Financial Data Mining?A reader may be motivated to explore both types of data mining due to the potential rewards. Furthermore, by studying both domains makes it possible to determine the financial impact of delivering software on time or with fewer defects.This paper examines 3 aspects related to both types of data mining. The underlying data used for constructing models, the models themselves, and validation techniques.
Dynamic Multi-branch Operational Plan's Modeling based on Meta-actions☆

Abstract Dynamic multi-branch operation plan's modeling (DMBPM) is the basic of operational plan simulation and evaluation by computer. By the way of decomposing the operational plan step by step, we can representing the dynamic multi-branch operational plan as “meta-actions” and their relationships. This method provides a way to deal with operational plan's dynamic adjusting additional with their simulation and evaluation. So, commander can make decision quickly based on the computer's aiding.
Immediate and long-term alterations in maximal electroshock seizure responsiveness in rats neonatally exposed to triethyltin bromide☆

Abstract Neonatal rats were injected (sc) with 0, 0.25, 0.5, 1.0, 2.5, or 5.0 mg/kg triethyltin bromide (TET) in a 2% ethanol vehicle on Days 0, 5, 10, 15, and 20 postnatally. TET-exposed neonates exhibited a dose-dependent delay in the ontogenetic appearance of both the clonic and tonic maximal electroshock seizure (MES) responses which were apparent up to Day 45, as evaluated by the MES grade distributions and the durations of the individual phases of the MES. In marked contrast, adult rats (exposed to TET only as neonates) exhibited long-term increases in MES severity, as evaluated by the durations of the individual phases of the MES. At 75 days of age, a time when the 1.0 mg/kg developmentally TET-treated group exhibited an increased seizure severity, a single challenge dose of 1.0 mg/kg TET (ip) produced a proportional decrease in MES severity in both developmentally treated and control rats. No changes in preweaning or postweaning body weight were observed in the animals in the 0.25, 0.5, 1.0, or 2.5 mg/kg groups. A 30% decrease in weaning weight and an approximate 15% decrease in postweaning weight were observed in the 5.0 mg/kg group. These seizure results demonstrate that developmental exposure to TET produces immediate and long-term alterations in central nervous system functioning, which are of an opposite character. Interestingly, we have previously shown that developmental lead exposure produces a similar developmental/adult dichotomy of effects with regard to the MES severity; however, the two patterns are reversed ( D. A. Fox, S. R. Overmann, and D. E. Woolley (1979) . Neurotoxicology 1, 149–170).
Isolation of a phytoalexin-detoxification gene from the plant pathogenic fungus Nectria haematococca by detecting its expression in Aspergillus nidulans

Abstract Detoxification of the pea phytoalexin pisatin via demethylation, mediated by a cytochrome P-450 monooxygenase, is thought to be important for pathogenicity of the fungus Nectria haematococca on pea. To isolate a fungal gene encoding pisatin demethylating activity (pda), we transformed Aspergillus nidulans with a genomic library of N. haematococca DNA constructed in a cosmid which carried the A. nidulans trpC gene. Transformants were selected for Trp+ and then screened for pda. One transformant among 1250 tested was Pda+ and was less sensitive to pisatin in culture than Pda−A. nidulans. The cosmid containing the gene (PDA) conferring this activity was recovered by phage λ packaging of transformant genomic DNA. When A. nidulans was transformed with the cloned cosmid, 98% of the Trp+ transformants were Pda+. RNA blots probed with a 3.35 kb subclone carrying PDA indicated that the gene is expressed constitutively in A. nidulans but is inducible by pisatin in N. haematococca.
Letter to the Editor-Some Characteristics of a Special Joint-Order Inventory Model

Joint ordering strategies are of extreme importance in many inventory control situations. This paper considers a situation involving two items having identical characteristics including unit Poisson demand. The joint ordering rule is to order both items up to a level Q each time the level of either of them drops to zero. Expressions for the probability mass function of the remnant stock, the expected value of the remnant stock, the expected time between orders, and the long-run cost per unit time are shown. The joint ordering strategy is compared with the situation where the two items are treated independently. When the cost of placing an order for two items is equal to that for a single item, it turns out that it is never preferable to use the independent strategy.
The role of transient damage annealing in shallow junction formation

Abstract Damage introduced into the Si substrate by ion-implantation can have a profound effect on the diffusion of dopants during rapid thermal annealing (RTA) or low temperature furnace annealing. In this paper defect production models are discussed for three cases: 1) low dose B+ implants, 2) B+ implants into preamorphized Si, and 3) BF2+, As+ and P+ self-amorphizing implants. Enhanced diffusion transients of dopants are related to the annealing of point-defect clusters, end-of-range dislocations and projected range misfit dislocations. Diffusion activation energies are reduced by the formation enthalpies of point defects generated by the annealing of implantation-induced damage.
A methoxyflurane delivery system for stereotaxic surgery

Abstract Methoxyflurane (2,2-dichloro-1,1-difluro-ethyl methyl ether; Metofane®) is a potent general inhalation anesthetic that is well-suited for small animal surgery. Methoxyflurane is particularly attractive as an anesthetic agent in neurological stereotaxic surgery, because methoxyflurane does not markedly attenuate the rate of anterograde or retrograde transport of horseradish peroxidase, or reduce the consistency and/or extent of excitatory neurotoxin damage. Methoxyflurane also is non-flammable when mixed with O 2 or air at anesthetic concentrations. The use of methoxyflurane anesthesia in stereotaxic surgery has been limited because methoxyflurane must be delivered via a vaporizer system that will easily interface with standard stereotaxic headholders. The present report describes a simple, reliable and inexpensive methoxyflurane delivery system for stereotaxic surgery.
Third-Order Elastic Constants of NaF

The complete set of third-order elastic constants for single crystals of NaF was determined from the hydrostatic-pressure and uniaxial-stress derivatives of natural sound velocities measured with a two-crystal ultrasonic-interference technique. There appeared to be no dislocation motion during the uniaxial measurements since changes in the natural sound velocities with stress were linear, and data recorded before and after a $\ensuremath{\gamma}$ irradiation agreed within experimental error. The Cauchy relations were not satisfied revealing that noncentral forces between the ions are appreciable. Calculations of the elastic constants were carried out according to the Born model. The high-temperature Gr\"uneisen constant and thermal-expansion coefficient were determined from the elasticity data and the latter compared with experimental results.
Effluent reduction and control of non-process elements towards a cleaner Kraft pulp mill

This work deals with the reduction of aqueous effluent and fresh water demand in a typical Kraft process to make the process cleaner and environment-friendly. The recycle and reuse of various aqueous streams present in the given process leads to a buildup of non-process elements, or NPEs. The challenges posed by this problem are solved using the holistic framework of mass integration. The approach consists of gaining process insights from the flow sheet followed by a rigorous mathematical optimization. A case study, dealing with the Kraft process, is looked at to demonstrate the potential benefits of the approach. Different NPE separation techniques, specific to the pulp and paper industry, are considered as part of the analysis. Various solution strategies are generated to achieve significant reductions in fresh water demands and waste water discharges for the Kraft process. The major changes in the process involve only piping changes. The principles developed are generic in nature and can be extended to other pulp processes as well.
ZnO Nanowires Grown by Chemical Bath Deposition in a Continuous Flow Microreactor

We report on a continuous flow microreactor for chemical bath deposition that enables rapid process characterization. The chemical bath flows through a submillimeter channel and material is deposited on a heated glass/silicon substrate that serves as one reactor wall. The microreactor operates in plug flow; bath composition changes as a function of distance down the reaction channel but the concentration profile is time-invariant. Spatially resolved characterization of the substrate enables rapid and direct correlation of material properties to growth conditions, which is not possible with a batch reactor where bath composition changes with time. We have used this microreactor to grow dense arrays of well-aligned, single-crystal ZnO nanowires. Slow flow rates result in nanowires whose lengths, growth mechanisms, and optical properties vary along the length of the substrate; fast flow rates produce nanowires that are more spatially uniform. Spatially resolved characterization of a single substrate reveals ...
MO‐G‐18C‐03: Evaluation of Deformable Image Registration for Lung Motion Estimation Using Hyperpolarized Gas Tagging MRI

Purpose: Hyperpolarized gas (HP) tagging MRI is a novel imaging technique for direct measurement of lung motion during breathing. This study aims to quantitatively evaluate the accuracy of deformable image registration (DIR) in lung motion estimation using HP tagging MRI as references. Methods: Three healthy subjects were imaged using the HP MR tagging, as well as a high-resolution 3D proton MR sequence (TrueFISP) at the end-of-inhalation (EOI) and the end-of-exhalation (EOE). Ground truth of lung motion and corresponding displacement vector field (tDVF) was derived from HP tagging MRI by manually tracking the displacement of tagging grids between EOI and EOE. Seven different DIR methods were applied to the high-resolution TrueFISP MR images (EOI and EOE) to generate the DIR-based DVFs (dDVF). The DIR methods include Velocity (VEL), MIM, Mirada, multi-grid B-spline from Elastix (MGB) and 3 other algorithms from DIRART toolbox (Double Force Demons (DFD), Improved Lucas-Kanade (ILK), and Iterative Optical Flow (IOF)). All registrations were performed by independent experts. Target registration error (TRE) was calculated as tDVF – dDVF. Analysis was performed for the entire lungs, and separately for the upper and lower lungs. Results: Significant differences between tDVF and dDVF were observed. Besides the DFD and IOF algorithms,more » all other dDVFs showed similarity in deformation magnitude distribution but away from the ground truth. The average TRE for entire lung ranged 2.5−23.7mm (mean=8.8mm), depending on the DIR method and subject's breathing amplitude. Larger TRE (13.3–23.7mm) was found in subject with larger breathing amplitude of 45.6mm. TRE was greater in lower lung (2.5−33.9 mm, mean=12.4mm) than that in upper lung (2.5−11.9 mm, mean=5.8mm). Conclusion: Significant differences were observed in lung motion estimation between the HP gas tagging MRI method and the DIR methods, especially when lung motion is large. Large variation among different DIR methods was also observed.« less
Statistical characteristics of pressure oscillations in a premixed combustor

Abstract This paper describes an investigation of the statistical characteristics of self-excited and noise-driven pressure oscillations in a premixed combustor. This work was motivated by observations that certain characteristics of these oscillations appear random and cannot be entirely characterized within a deterministic framework (e.g., spontaneous, noise-induced transitions of the combustor from stable to unstable operation or cycle-to-cycle variations in the oscillating pressure). In an effort to elucidate these stochastic elements, we performed an analysis of cycle-to-cycle variations in combustor pressure whose results are described in this paper. Data obtained from our combustor shows that the probability density function of the amplitude of these oscillations transitions from a Rayleigh to a Gaussian-type distribution as the combustor moves from stable to unstable operation. These data also show that the instability phase is nearly uniformly distributed; i.e., there is no phase value with maximum probability of occurrence. We also describe a theoretical analysis of the statistical features of a non-linear combustor model that is forced by random noise. Solutions of this model are presented and shown to be in agreement with measured data. The good agreement between the predictions and measured data suggest that the analysis presented in this paper provides a useful framework for interpreting many other apparently random features of combustor stability characteristics; for example, cyclic variability, “fuzziness” in stability boundaries, or noise-induced transitions.
Inhibition of deoxyribonuclease I of human serum in vitro by nitrogen mustard or leucocyte extracts.

Abstract The temperature, time of incubation, concentration of MgCl2 · 6H2O and concentration of serum required for an optimum activity of deoxyribonuclease I (DNase I) of human serum were studied. The final incubation mixture consisted of 2 ml. of serum, 2 mg. deoxyribonucleic acid (DNA), 3 mg. MgCl2 · 6H2O, 0.5 ml. of 0.1 tM tris(hydroxymethyl) aminomethane buffer pH 7.3, and 0.1 ml. toluene in a total volume of 3 ml. After 20 hr. of incubation at 45 °C., determinations of DNase I were made by measuring deoxyribose-purine-containing fragments in the trichloroacetic acid-soluble fraction. Addition of 2 mg. nitrogen mustard or 0.5 ml. leucocyte extract to the incubation mixture inhibited the DNase I activity of the human serum. Enzyme kinetic studies indicate a noncompetitive relationship between DNA and nitrogen mustard [methylbis(β-chloroethyl)amine hydrochloride]for the DNase I of human serum; however, the inhibitor in the leucocyte extracts lowered the human serum DNase I activity in a competitive manner.
Perturbation solutions for the shape of a solidification interface subjected to a spatially periodic heat flux

In the manufacture of certain high-technology materials (such as strengthened composites for turbine and compressor blades) from a melt, it is essential to control the heat transfer conditions in such a way that a planar solidification interface is maintained within a given tolerance. Spatial nonuniformities in the heat flux imposed along the solidification interface may cause deformation. In this paper the author analyzes the interfacial shapes resulting from a periodic heat flux variation along the interface. Two cases of practical interest are examined. In case (a) the amplitude of heat flux for variation is assumed small compared to the mean value, and in case (b) the wavelength of the imposed heat flux variation is considered to be much larger than a characteristic length in the transverse direction. In both cases, sensitivity of the interface shape with respect to heat flux nonuniformities is also determined.
Developing and Managing Digital/Technology Literacy and Effective Learning Skills in Adult Learners

The needs of adult learners are different from those of traditional undergraduate students, and programs must be designed to meet this need. In particular, digital and technology literacy needs, including general computing skills, computerized communications, online and distance learning, and Web 2.0 tools make navigating coursework an additional challenge. In this paper, the authors examine the technology and digital literacy needs and backgrounds of adult learner students and discuss research on the interaction between technology and adult learner education. Using the features of intensive weekend classroom sessions, on-line distance learning, and specialized teaching methods, an improved learning environment tailored to unique needs and career goals can be offered to business undergraduate adults. An important component is the development of technology and digital literacy skills to â€œfill the gapsâ€ of students who may have extensive business or working experience, but are less than proficient in the use of technology. More depth and analysis is given to the following areas: digital and technology skills and knowledge improvement, pedagogical features, the use of intensive weekend and evening sessions, and the role of distance learning to supplement the classroom sessions.
TRANSLOCATION OF STRONTIUM FROM LEAVES OF BEAN AND CORN PLANTS

Abstract Translocation of Sr85 from leaves of bean and corn plants to plant parts was measured at successive stages of growth. Translocation was greater from leaf applications that were periodically rewetted than from applications allowed to air dry and stay dry. The maximum amount of Sr85 translocated from rewetted bean and corn leaves was about 0·6 and 0·5 per cent, respectively, of that applied. In bean plants the greatest translocation occurred from the youngest leaf (fourth trifoliate), treated 20 days after the straightening of the hypocotyl. In corn this occurred from the youngest leaf (leaf nearest the tassel) treated 10 days before pollination. Translocation of Sr85 into roots and fruit parts, from rewetted applications, was less than 0·006 per cent of that applied. From most foliar treatments, allowed to air dry and stay dry, translocation was less than 0·01 per cent of that applied.
Inducible nitric oxide synthase is present in motor neuron mitochondria and Schwann cells and contributes to disease mechanisms in ALS mice

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of motor neurons (MNs). The molecular pathogenesis of ALS is not understood, thus effective therapies for this disease are lacking. Some forms of ALS are inherited by mutations in the superoxide dismutase-1 (SOD1) gene. Transgenic mice expressing human Gly93 → Ala (G93A) mutant SOD1 (mSOD1) develop severe MN disease, oxidative and nitrative damage, and mitochondrial pathology that appears to involve nitric oxide-mediated mechanisms. We used G93A-mSOD1 mice to test the hypothesis that the degeneration of MNs is associated with an aberrant up-regulation of the inducible form of nitric oxide synthase (iNOS or NOS2) activity within MNs. Western blotting and immunoprecipitation showed that iNOS protein levels in mitochondrial-enriched membrane fractions of spinal cord are increased significantly in mSOD1 mice at pre-symptomatic stages of disease. The catalytic activity of iNOS was also increased significantly in mitochondrial-enriched membrane fractions of mSOD1 mouse spinal cord at pre-symptomatic stages of disease. Reverse transcription-PCR showed that iNOS mRNA was present in the spinal cord and brainstem MN regions in mice and was increased in pre-symptomatic and early symptomatic mice. Immunohistochemistry showed that iNOS immunoreactivty was up-regulated first in spinal cord and brainstem MNs in pre-symptomatic and early symptomatic mice and then later in the course of disease in numerous microglia and few astrocytes. iNOS accumulated in the mitochondria in mSOD1 mouse MNs. iNOS immunoreactivity was also up-regulated in Schwann cells of peripheral nerves and was enriched particularly at the paranodal regions of the nodes of Ranvier. Drug inhibitors of iNOS delayed disease onset and significantly extended the lifespan of G93A-mSOD1 mice. This work identifies two new potential early mechanisms for MN degeneration in mouse ALS involving iNOS at MN mitochondria and Schwann cells and suggests that therapies targeting iNOS might be beneficial in treating human ALS.
Estimated risk of hepatotoxicity after an acute acetaminophen overdose in alcoholics

Abstract A published logistic regression model based on the Canadian Acetaminophen Overdose Study registry was used to calculate the risk of hepatotoxicity after an acute acetaminophen overdose and to estimate a treatment threshold line for alcoholic patients who did not co-ingest alcohol (i.e., abstinent alcoholics) on the Rumack–Matthew nomogram. The risk of hepatotoxicity in nonalcoholic and abstinent alcoholic patients was calculated at the acetaminophen concentration of 150 μg/ml at 4 h (37.5 μg/ml at 12 h) treatment threshold line. This corresponds to the “possible risk” line on the Rumack–Matthew nomogram and represents a 1.6% risk of hepatotoxicity for nonalcoholic patients at or below this line. At or below this same 150 μg/ml at 4-h line, abstinent alcoholic patients have a hepatotoxicity risk of 10.7%. The risk of hepatotoxicity in abstinent alcoholics' equivalent to that of nonalcoholics (i.e., 1.6%) occurs at a lower acetaminophen concentrations treatment threshold line, that is, 104 μg/ml at 4 h (26 μg/ml at 12 h). Because of difficulties plotting this new line on the familiar Rumack–Matthew semilogarithmic scale, a line connecting 100 μg/ml at 4 h (25 μg/ml at 12 h) is proposed. This line equates to a 1.1% risk of hepatotoxicity in abstinent alcoholic patients. The analysis supports the observation that based on the published model abstinent alcoholics might have a greater risk of hepatotoxicity after an acute acetaminophen overdose. This proposed new risk line can be used in hypothesis generation for future clinical studies in this alcohol related problem.
Fracture topography of brittle polymers

Fracture surfaces record the kinetics of failure at two levels in the structure of polymeric solids. The first is evidenced by the formation of geometric markings resulting from the interaction of the primary fracture front with secondary fractures developing radially just ahead of the primary fracture. These markings are often visible to the unaided eye and have minimal dimensions in the micron range. The second fracture phenomenon appears to involve the orientation of molecular chains or bundles. Such orientation manifests itself in the interference-color producing film found on the fracture surfaces of poly (methylmethacrylate) and polystyrene. It is also apparent in the free or adherent film found on the surfaces of large fractured crazes. Some evidence is presented for the existence in these films of chain bundles 30A or less in diameter. It would seem that similar mechanisms are operating in the production of “craze matter” and of fracture surface films.
The Role of 1:1 Individual Instruction in Reading

General education classrooms are increasingly diverse as students with and without disabilities learn alongside one another. At each level, all students are learning to read and reading to learn standards-based content. A worry among some general and special educators who otherwise support the principles of inclusive education is what to do about the differences in academic levels between students with and without disabilities. This question is raised frequently in regard to reading instruction. This article makes a case for the use of 1:1 instruction that is often delivered in the general education classroom as a model for providing students with disabilities with access to specialized assistance.
Estimating Cell Concentration in Three-Dimensional Engineered Tissues Using High Frequency Quantitative Ultrasound

Histology and biochemical assays are standard techniques for estimating cell concentration in engineered tissues. However, these techniques are destructive and cannot be used for longitudinal monitoring of engineered tissues during fabrication processes. The goal of this study was to develop high-frequency quantitative ultrasound techniques to nondestructively estimate cell concentration in three-dimensional (3-D) engineered tissue constructs. High-frequency ultrasound backscatter measurements were obtained from cell-embedded, 3-D agarose hydrogels. Two broadband single-element transducers (center frequencies of 30 and 38 MHz) were employed over the frequency range of 13–47 MHz. Agarose gels with cell concentrations ranging from 1 × 104 to 1 × 106 cells mL−1 were investigated. The integrated backscatter coefficient (IBC), a quantitative ultrasound spectral parameter, was calculated and used to estimate cell concentration. Accuracy and precision of this technique were analyzed by calculating the percent error and coefficient of variation of cell concentration estimates. The IBC increased linearly with increasing cell concentration. Axial and lateral dimensions of regions of interest that resulted in errors of less than 20% were determined. Images of cell concentration estimates were employed to visualize quantitatively regional differences in cell concentrations. This ultrasound technique provides the capability to rapidly quantify cell concentration within 3-D tissue constructs noninvasively and nondestructively.
Laser Fabrication of Microstructures: Effect of Geometrical Scaling on Chemical Reaction Rates

Laser chemical processing for microfabrication makes use of chemical reactions and phase changes confined to micrometer-scale dimensions at vapor/solid and liquid/solid interfaces. When conditions are established for rapid interfacial reactions, processing speeds can become limited by diffusive transport. These diffusion-limited rates, however, increase by many orders of magnitude as the microreaction geometry is reduced to micrometer lengths using well-focused visible and UV beams. A calculation of the geometric scaling of such rates is summarized here. For realistic conditions, rate increases of up to four decades are predicted relative to corresponding reactions on semi-infinite plane surfaces.
Integrated segmentation and motion analysis of cardiac MR images using a subject-specific dynamical model

In this paper we propose an integrated cardiac segmentation and motion tracking algorithm. First, we present a subject-specific dynamical model (SSDM) that simultaneously handles inter-subject variability and temporal dynamics (intra-subject variability), such that it can progressively identify the subject vector associated with a new cardiac sequence, and use this subject vector to predict the subject-specific segmentation of the future frames based on the shapes observed in earlier frames. Second, we use the segmentation as a guide in selecting feature points with significant shape characteristics, and invoke the generalized robust point matching (G-RPM) strategy with boundary element method (BEM)-based regularization model to estimate physically realistic displacement field in a computationally efficient way. The integrated algorithm is formulated in a recursive Bayesian framework that sequentially segments cardiac images and estimates myocardial displacements. ldquoLeave-one-outrdquo validation on 32 sequences demonstrates that the segmentation results are improved when the SSDM is used, and the tracking results are much more accurate when the segmentation module is added.
Algorithm transformation techniques for concurrent processors

Progress in supercomputing technology has led to two major trends. First, many existing algorithms need to be redesigned for efficient concurrent implementation using supercomputers. Second, a continuous increase will be apparent in the number of application-specific VLSI integrated circuits, which can provide the performance of supercomputers using single chips or chipsets (at the expense of design time for algorithm and architecture development). Both of these approaches require considerable effort in the development of algorithms for specific applications. Four independent algorithm transformation methodologies-program unfolding, retiming, look-ahead algorithms, and index mapping transformations-are reviewed. These transformation techniques exploit the available parallelism in iterative data-flow programs and create additional parallelism if necessary. >
EXPERIMENTAL PULMONARY TUBERCULOSIS IN THE DOG : THE EFFECT OF LARGE AMOUNTS OF TUBERCLE BACILLI OF BOVINE TYPE INTRODUCED DIRECTLY INTO THE LUNGS BY WAY OF THE AIR PASSAGES.

It is obvious, as stated in the beginning, that these experiments have failed to reproduce a chronic pulmonary tuberculosis. Acute pneumonic processes of tubercular origin are, however, not infrequent as a complicating or terminal process in pulmonary phthisis, and there have been several cases described in which individuals have died with the symptom complex of acute lobar pneumonia, in which it developed at post-mortem examination that the disease was tuberculosis. Our experiments throw some light on debated questions in connection with these acute pneumonic forms of phthisis. In our experiments we believe that we have effectively reproduced this exudative type of tuberculosis of the lungs. This type of lesion may, in the light of our experiments, result from the sudden bronchogenic invasion of large numbers of virulent tubercle bacilli in a relatively resistant animal. The large mononuclear cells so frequently encountered in the exudate seem to be brought there chiefly from outside.(1) As Orth found when studying human material, it is difficult here also, to exclude the possibility that similar cells may result from the desquamation of alveolar epithelium. The tubercle bacillus alone, without the aid of secondary infection, is competent to produce a type of lesion which leads to necrosis of the bronchi, and by discharge of the necrotic material to cavity formation. As judged by our experiments the bronchi are less resistant to involvement in the necrosis than are the blood vessels or pleural surfaces. The fact that by the method of bronchial insufflation of Lamar and Meltzer a characteristic tuberculous pneumonia may be produced makes it probable that the lobar pneumonias generally are of bronchogenic origin.
Variations in Resource Utilization Among Medical Specialties and Systems of Care

As sweeping changes in the organization and delivery of health care are implemented, it is important to examine the relationship between various types of cost-containment efforts, health care costs, and quality of care. This article reviews the evidence that physician specialty training, the organization of physicians, and the method of physician payment are significant influences upon the utilization of health care services. Data from before the late 1980s raised the possibility that family practitioners employed fewer resources than general internists and that health maintenance organizations used fewer resources than solo practitioners. However, the studies from which these data were derived were marred by insufficient attention to patient mix, failure to account for interactions between specialty and system, and inadequate regard for the complexities of modern practice structures. More recent data from the Medical Outcomes Study (MOS) overcomes some but not all of these problems. In general, it can be...