A Pattern-Based Framework for Software Anomaly Detection

This paper presents a pattern-based framework for developing tool support to detect software anomalies. The use of a pattern-based approach is important because it provides the flexibility needed to address domain-specific needs, with respect to the types of problems the tools detect and the strategies used to inspect and adapt the code. Patterns can be used to detect a variety of problems, ranging from simple syntactic issues to difficult semantic problems requiring global analysis. Patterns can also be used to describe transformations of the software, used to rectify problems detected through software inspection, and to support interactive inspection and adaptation when full automation is impractical. This paper describes a part of the Knowledge Centric Software (KCS) framework that embodies the pattern-based approach and provides capabilities for addressing different languages and different application domains. While only the part of the framework relevant to code inspections is addressed in this paper, in future, we also expect to address UML analysis and design models. As an application of the research, we present an overview of an inspection tool being developed for high assurance software for avionics systems.     

Multitarget dielectrophoresis activated cell sorter

The ability to rapidly and efficiently isolate specific viruses, bacteria, or mammalian cells from complex mixtures lies at the heart of biomedical applications ranging from in vitro diagnostics to cell transplantation therapies. Unfortunately, many current selection methods for cell separation, such as magnetic activated cell sorting (MACS), only allow the binary separation of target cells that have been labeled via a single parameter (e.g., magnetization). This limitation makes it challenging to simultaneously enrich multiple, distinct target cell types from a multicomponent sample. We describe here a novel approach to specifically label multiple cell types with unique synthetic dielectrophoretic tags that modulate the complex permittivities of the labeled cells, allowing them to be sorted with high purity using the multitarget dielectrophoresis activated cell sorter (MT-DACS) chip. Here we describe the underlying physics and design of the MT-DACS microfluidic device and demonstrate approximately 1000-fold enrichment of multiple bacterial target cell types in a single-pass separation.     

Development of an optimized expression system for the screening of antibody libraries displayed on the Escherichia coli surface

Polypeptide library screening technologies are critically dependentupon the characteristics of the expression system employed.A comparative analysis of the lpp–lac, tet and araBAD promoterswas performed to determine the importance of tight regulationand expression level in library screening applications. Thesurface display of single-chain antibody (scFv) in Escherichiacoli as an Lpp–OmpA' fusion was monitored using a fluorescentlytagged antigen in conjunction with flow cytometry. In contrastto the lpp–lac promoter, both tet and araBAD promoterscould be tightly repressed. Tight regulation was found to beessential for preventing rapid depletion of library clones expressingfunctional scFv and thus for maintaining the initial librarydiversity. Induction with subsaturating inducer concentrationsyielded mixed populations of uninduced and fully induced cellsfor both the tet and araBAD expression systems. In contrast,homogeneous expression levels were obtained throughout the populationusing saturating inducer concentrations and could be adjustedby varying the induction time and plasmid copy number. Underoptimal induction conditions for the araBAD system, proteinexpression did not compromise either cell viability or librarydiversity. This expression system was used to screen a libraryof random scFv mutants specific for digoxigenin for clones exhibitingimproved hapten dissociation kinetics. Thus, an expression systemhas been developed which allows library diversity to be preservedand is generally applicable to the screening of E.coli surfacedisplayed libraries.     

Sustaining the development of primary care in academic medicine. Working Group on Sustaining the Development of Academic Primary Care. Association of American Medical Colleges

Dietary supplementation of very long-chain n-3 fatty acids to rats reduces postprandial plasma concentrations of triacylglycerol, unesterified fatty acids and glycerol after long-term feeding by unknown mechanisms [Rustan et al., J. Lipid Res. 34 (1993) 1299-1309]. In the present study we examine the role of adipose tissues in metabolism of fatty acids. Postprandial plasma concentrations of triacylglycerol, unesterified fatty acids and glycerol were reduced by 75%, 50% and 30%, respectively, during 49 days of feeding high-fat diets containing n-3 fatty acids (6.5% n-3 fatty acid concentrate, 13% lard) as compared to lard (19.5% lard). These differences were observed already after two days of feeding. Plasma concentration of unesterified very long-chain n-3 fatty acids increased to 50 microM in n-3 fatty acid-supplemented rats, whereas these fatty acids were undetectable in lard-fed animals. The n-3 fatty acid-enriched diet limited cell volumes of perirenal and epididymal adipocytes by 40% and 30%, respectively, after 49 days, as compared to lard feeding. This reduction in cell volume was not due to reduced synthesis of glycerolipids in epididymal adipocytes. Acute incubation of perirenal and epididymal adipocytes with oleic acid or eicosapentaenoic acid, caused similar increase in synthesis of triacylglycerol. Dietary supplementation with n-3 fatty acids decreased basal and total lipolysis (isoprenalin-stimulated) in perirenal adipocytes. Basal lipolysis in epididymal adipocytes was reduced by n-3 fatty acids only after 49 days. n-3 fatty acids increased total lipolysis in mesenteric and subcutaneous fat cells compared to adipocytes derived from lard-fed animals, whereas basal lipolysis was unchanged. These results suggest that the reduced postprandial plasma concentration of unesterified fatty acids after n-3 fatty acid-supplementation is not caused by accumulation of fatty acids in adipose tissue. The reduced trophic growth of adipocytes might be due to decreased supply of unesterified fatty acids for triacylglycerol storage. (c) 1998 Elsevier Science B.V.     

Analysis of porosity associated with Hanford 3013 outer container welds

An unacceptable degree of porosity was identified in several closure welds on stainless steel containers for plutonium-bearing materials. The pores developed in the weld tie-in region due to gas trapped by the weld pool during the closure process. This paper describes the efforts to trace the root cause of the porosity to the geometric conditions of the weld joint and establish corrective actions to minimize such porosity.     

The quantitative determination of glass in slag by infrared spectroscopy

Determinations of the glass content of synthetic and blast furnace slags by infrared absorption spectroscopy are described. A linear relationship exists between the calculated infrared absorption R-values and the percentage glass determined by optical microscopy count. The use of an internal standard and a constant grinding time for the slag sample are crucial to obtaining an accurate and reproducible result. The technique is simple, inexpensive, and minimizes time consuming sample preparations such as washings and particle sizings common in the optical microscopy method.     

Unification of the models for types, classes and state machines

The static model, specified formally, and the dynamic model, represented by hierarchical state machines, are intimately related. By defining a mapping between the two, we are able to provide a definition of inheritance, multiple inheritance and behavioral subtyping for state machines based on that for formally specified types and classes, and provide a graphical representation for formal specifications in terms of state machines. The state machine notation is based on statecharts. It, however, supports both a declarative style, appropriate for types, and an imperative style, appropriate for classes. State machines may be parameterized and may be viewed from different perspectives, based on an arbitrary choice of state predicates. And states are interpreted not as an expression of concurrency, but result from a choice of independent state predicates.     

Rapid isolation of high-affinity protein binding peptides using bacterial display

A robust bacterial display methodology was developed that allows the rapid isolation of peptides that bind to arbitrarily selected targets with high affinity. To demonstrate the utility of this approach, a large library (5 x 10(10) clones) was constructed composed of random 15-mer peptide insertions constrained within a flexible, surface exposed loop of the Escherichia coli outer membrane protein A (OmpA). The library was screened for binding to five unrelated proteins, including targets previously used in phage display selections: human serum albumin, anti-T7 epitope mAb, human C-reactive protein, HIV-1 GP120 and streptavidin. Two to four rounds of enrichment (2-4 days) were sufficient to enrich peptide ligands having high affinity for each of the target proteins. Strong amino acid consensus sequences were apparent for each of the targets tested, with up to seven consensus residues. Isolated peptide ligands remained functional when expressed as insertional fusions within a monomeric fluorescent protein. This bacterial display methodology provides an efficient process for identifying peptide affinity reagents and should be useful in a variety of molecular recognition applications.     

Marital interaction in alcoholic and nonalcoholic couples: Alcoholic subtype variations and wives' alcoholism status.

The authors examined problem-solving marital interactions of alcoholic and nonalcoholic couples (N = 132). Four alcoholic groups (husband alcoholic with antisocial personality disorder or not, paired with alcoholic or nonalcoholic wives) were compared with each other and with a both-spouses-nonalcoholic group. Consistent with the alcoholic subtypes hypothesis, couples with an antisocial alcoholic husband had higher levels of hostile behavior regardless of wives' alcoholism status. In contrast, rates of positive behaviors and the ratio of positive to negative behaviors were greatest among couples in which either both or neither of the spouses had alcoholic diagnoses and were lowest among alcoholic husbands with nonalcoholic wives. Discussion focuses on possible mechanisms linking antisocial alcoholism and discrepant alcoholic diagnoses to poorer marital outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

汽车开关稳压器具有输入瞬变电压保护功能

当电压稳压器遭遇高于输入供电范围的瞬间高压时．工程师经常面临两难选择。这种情形经常发生在汽车应用中．交流发电机甩负荷（load dump）的高压瞬变可以产生36V～75V的电压,持续长达400ms。设计人员必须在能经受住这样大限度输入电压的稳压器或使用输入保护方案之间做出选择。本设计实例的简单电路提供了箝位来自电池的瞬间高达50V的输入电压的低成本高效率方法,以便利用20V 3MHz稳压器。用这个电路,设计师可以用相对低的费用实现小的整体占位面积,因为采用3MHz稳压器,且可以使用不必承受50V电压的低压元件。