Software fault characteristics: A synthesis of the literature

Faults continue to be a significant problem in software. Understanding the nature of these faults is important for practitioners and researchers. There are many published fault characteristics schemes but no one scheme dominates. Consequently it is difficult for practitioners to effectively evaluate the nature of faults in their software systems, and it is difficult for researchers to compare the types of faults found by different fault detection techniques. In this paper we synthesise previous fault characteristics schemes into one comprehensive scheme. Our scheme provides a richer view of faults than the previous schemes published and presents a comprehensive, unified approach which accommodates the many previous schemes. A characteristics-based view of faults should be considered by future researchers in the analysis of software faults and in the design and evaluation of new fault detection tools. We recommend that our fault characteristics scheme be used as a benchmark scheme

Utility based cross-layer collaboration for speech enhancement in wireless acoustic sensor networks

A wireless acoustic sensor network is considered that is used to estimate a desired speech signal that has been corrupted by noise. The application layer of the WASN derives an optimal filter in a linear MMSE sense. A utility function is then used in conjunction with the MMSE estimate in order to evaluate the most significant signal components from each node in the system. The utility values are used as a cross-layer link between the application layer and the network layer so the nodes transmit the signal components that are deemed most relevant to the estimate while adhering to the power constraints of the system. The simulation results show that a high signal-to-error and signal-to-noise ratio is still achievable while transmitting a subset of signal components

Mast cell activation test as a diagnostic tool in chlorhexidine allergy and to study cross-reactivity

Background: Chlorhexidine (CHX) allergy has become a predominant cause of perioperative hypersensitivity (POH) including anaphylaxis. In general, confirmatory diagnosis of CHX-allergy starts with skin tests (STs) and quantification of CHX specific immunoglobulin E (sIgE). However, in some cases diagnosis remains challenging, mainly because of divert results between both methods. The passive mast cell activation test (pMAT) could improve diagnosis and possibly elicit cross-reactivity between CHX and structurally similar compounds such as alexidine (ALX) and octenidine (OCT). Objective: Confirming the hypothesis that the pMAT, in which donor mast cells (MCs) are passively sensitised with CHX-sIgE reactive sera, might benefit diagnosis of IgE-mediated CHX allergy and to study whether pMAT enables to demonstrate cross-reactivity between CHX and ALX and/or OCT. Methods: Human MCs were generated from peripheral blood CD34+ progenitor cells and sensitised with sera from 30 patients with a documented CHX-allergy (CHX-sIgE+ in addition to positive STs and/or positive basophil activation test [BAT]), 9 patients with CHX sensitisation (CHX-sIgE+, ST-, BAT-) and 20 control individuals (CHX-sIgE-, ST-). MCs were then stimulated with CHX to assess degranulation. Additionally, cells were sensitised with sera from 10 CHX-allergic patients who tested positive in pMAT, 5 CHX-sensitised patients and 5 healthy controls and subsequently challenged with ALX and OCT. MC degranulation was measured via quantification of up-regulation of the lysosomal degranulation marker CD63. Results: MCs showed activation for 12/13 CHX-allergic patients with positive ST and BAT, 7/11 CHX-allergic patients with positive ST and no BAT and 3/6 CHX-allergic patients with negative ST but positive BAT. ALX and OCT responsiveness was demonstrable with 4/10 and 3/10 of the sera of CHX-allergic patients, respectively. No reactivity to CHX, ALX nor OCT was demonstrable when using sera from CHX-sensitised patients or when using sera from control individuals. MCs incubated with CHX, OCT and ALX without prior passive sensitisation with patients’ sera remained unresponsive to all three antiseptics. Conclusion: The pMAT is a reliable diagnostic of which the application could be extended from traditional proteinaceous allergens to small molecules such as drugs. Unlike BAT, deferred and more standardized batch analyses are possible, making it easier to translate in a clinically valuable diagnostic. In addition, pMAT constitutes an attractive tool to explore cross-reactivity between structurally similar compounds, including (preclinical) assessment of molecules not approved for human use yet.Bakgrunn: Klorheksidin (CHX) allergi har blitt en ledende årsak til perioperativ overfølsomhet (POH) og anafylaksi. Hudtester (STs) og måling av CHX spesifikke immunglobulin E (sIgE) kan brukes for å diagnostisere CHX-allergi. Å diagnostisere CHX-allergi på denne måten har i noen tilfeller vist seg å være utfordrende, hovedsakelig grunnet ulike resultater fra de to metodene. Passiv mastcelle aktiveringstest (pMAT) kan forbedre diagnostiseringen av CHX-allergi og muligens vise kryssreaktivitet mellom CHX og andre strukturelt lignende forbindelser som alexidin (ALX) og octenidin (OCT). Mål: Bekrefte hypotesen om at pMAT, hvor donor mastceller (MCs) er passivt sensibilisert med CHX-sIgE reaktivt sera, kan forbedre diagnostiseringen av IgE-mediert CHX-allergi samt undersøke om pMAT kan brukes til å demonstrere kryssreaktivitet mellom CHX og ALX og/eller OCT. Metode: Humane mastceller ble generert fra perifere CD34+ progenitorceller og sensibilisert med sera fra 30 pasienter med dokumentert CHX-allergi (CHX-sIgE+ i tillegg til positiv hudtest og/eller positiv basofil aktiveringstest [BAT]), 9 pasienter med CHX sensibilisering (CHX-sIgE+, ST-, BAT-) samt en kontrollgruppe på 20 individer (CHX-sIgE-, ST-). MCs ble så stimulert med CHX for å vurdere degranulering. MCs ble også sensibilisert med sera fra 10 CHX-allergiske pasienter som testet positivt i pMAT, 5 CHX-sensibiliserte pasienter, samt 5 friske kontroller, og deretter stimulert med ALX og OCT. MC degranulering ble målt ved en kvantifisering av oppregulering av den lysosomale degranuleringsmarkøren CD63. Resultat: MCs viste aktivering for 12/13 CHX-allergiske pasienter med positiv ST og BAT, 7/11 CHX-allergiske pasienter med positiv ST og ingen BAT og 3/6 CHX-allergiske pasienter med negativ ST, men positiv BAT. MC aktivering av ALX og OCT ble demonstrert for henholdsvis 4/10 og 3/10 sera av CHX-allergiske pasienter. Ingen reaktivitet mot CHX, ALX og heller ikke OCT ble demonstrert når sera fra CHX-sensibiliserte pasienter eller kontroll individer ble brukt. MCs som ble inkubert med CHX, OCT eller ALX uten tidligere passiv sensibilisering med pasientens sera, viste ingen aktivering. Konklusjon: pMAT er en pålitelig diagnostikk hvorav applikasjonen kan utvides fra proteinholdige allergener til små molekyler slik som legemidler. I motsetning til BAT, mer standardiserte batch analyser er mulig, som gjør det lettere å gjøre det til et klinisk verdifullt diagnoseverktøy. I tillegg kan pMAT brukes til å undersøke kryssreaktivitet mellom strukturelt lignende forbindelser, som inkluderer molekyler som ennå ikke er godkjent for human bruk.M-BIOTE

Minimal Necessary Weed Control Does Not Increase Weed-Mediated Biological Pest Control in Romaine Lettuce (Lactuca sativa L., var. Romana)

Lettuce is one of the most consumed leafy greens. Depending on the variety, it is ready for harvesting 40–80 days after sowing, and therefore several growth cycles can be concluded within a growing season. Due to its high market standards, lettuce may require intensive management. This study implemented a critical period of weed interference (CPWI) trial to understand at which moment of the cropping cycle weeds can be tolerated without impacting crop yield to decrease the time needed for weeding and assess the potential support weeds can give to biological pest control in lettuce. Treatments represented two gradients of weed intensity: (1) increasingly weed-free, and (2) increasingly weedy. Dose–response curves were produced to find the CPWI based on lettuce relative yield. RLQ analysis was used to explore the relationships between weeding regime and weed functional traits for biological pest control. Yield was above the 5% acceptable yield loss threshold in all plots kept weed-free for 20 days or more, indicating a necessary weed-free period of 20 days from transplanting. However, the support of beneficial insects was not guaranteed at the end of the necessary weed-free period. We suggest that it is possible to limit intense weed management to the beginning of the growing season, reducing the cost of plastic mulches and increasing on-farm biodiversity, but field margins could be better suited to deliver conservation biological control in short-term crops where this service is of primary interest

On some differential-geometric aspects of the Torelli map

In this note we survey recent results on the extrinsic geometry of the Jacobian locus inside $\mathsf{A}_g$. We describe the second fundamental form of the Torelli map as a multiplication map, recall the relation between totally geodesic subvarieties and Hodge loci and survey various results related to totally geodesic subvarieties and the Jacobian locus.Comment: To appear on Boll. UMI, special volume in memory of Paolo de Bartolomei

An empirical study into COBOL type inferencing

AbstractIn a typical COBOL program, the data division consists of 50% of the lines of code. Automatic type inference can help to understand the large collections of variable declarations contained therein, showing how variables are related based on their actual usage. The most problematic aspect of type inference is pollution, the phenomenon that types become too large, and contain variables that intuitively should not belong to the same type. The aim of the paper is to provide empirical evidence for the hypothesis that the use of subtyping is an effective way for dealing with pollution. The main results include a tool set to carry out type inference experiments, a suite of metrics characterizing type inference outcomes, and the experimental observation that only one instance of pollution occurs in the case study conducted

Climate change in Italy indicated by agrometeorological indices over 122 years

To determine the risk of climate change for agriculture it is necessary to define a set of agrometeorological parameters, derived from the classic climate parameters, that are capable of indicating the consequences of climate change for crop production. In this study high-quality daily rainfall, evaporation and mean, minimum and maximum temperature data collected since 1878 at the meteorological station of the Department of Agronomy and Agroecosystem Management of the University of Pisa, Italy (H = 6 in a.s.l.; latitude = 43degrees41'; longitude = 10degrees23'E) were used to calculate extreme temperature and rainfall events, frost risk, flooding risk and drought risk. Time trends for all variables were analysed using linear regression techniques. Results indicate that the changes in extreme events in Pisa have not changed in a way that is likely to negatively affect crop production. The risk of crop damage due to frost has decreased and sowing time in spring can safely be anticipated. The soil moisture surplus (SMS) and theoretical irrigation requirement (TIR) have not changed despite a decreasing rainfall trend. The number of soil moisture surplus days in autumn has decreased indicating a decrease in flooding risk, which can have a positive effect on soil workability. (C) 2002 Elsevier Science B.V. All rights reserved

Characterization of pharyngeal hypocontractility patterns during deglutition: High Resolution Impedance Manometry findings

Introduction High resolution impedance manometry (HRIM) provides an objective measure of pharyngeal pressurization and bolus flow and can be analysed using pressure flow analysis (PFA). The aim of the study is to investigate different types of pharyngeal hypocontractility and their distribution in patients with pharyngeal dysphagia. Material and Methods A cohort study was conducted on patients with dysphagia referred for HRIM. Inclusion criteria were abnormal (<5th percentile) pharyngeal contractile integral (PhCI) or abnormal regional contractile integrals (velo- or meso- or hypo-pharyngeal integrals). PFA was performed on 10ml liquid swallows using the Swallow GatewayTM open access analysis portal. Patients were classified based on a proposed HRIM scheme. The distribution of PFA metrics was compared between patients with normal and abnormal PhCI using the chi-squared test. Results In total 38 patients were studied and 137 swallows were analysed. Absent pharyngeal contractility was found in 5.3% (2/38) of the patients, ineffective pharyngeal contractility in 68.4% (26/38), and fragmented pharyngeal contractility in 26.3% (10/38). Regional weakness was mainly observed in the mesopharynx (94.7% of the patients), followed by the hypopharynx (50%) and the velopharynx (15.8%). A combined disorder of pharyngeal propulsion and UES restriction was seen in 44.7% (17/38) of the patients. Patients with a normal PhCI (fragmented pharyngeal contractility) were more likely to present an abnormal integrated relaxation pressure at the level of the upper esophageal sphincter (\u3c72=14.56, p=0.001) Conclusion Based on the pharyngeal contractile integrals, two main types of pharyngeal hypocontractility are present in the clinical population of patients: ineffective and fragmented pharyngeal contractility. Totally absent peristalsis in uncommon. In almost half of the patients, pharyngeal propulsion disorders are combined to disorders of UES restriction