An LP-based inconsistency monitoring of pairwise comparison matrices

A distance-based inconsistency indicator, defined by the third author for the consistency-driven pairwise comparisons method, is extended to the incomplete case. The corresponding optimization problem is transformed into an equivalent linear programming problem. The results can be applied in the process of filling in the matrix as the decision maker gets automatic feedback. As soon as a serious error occurs among the matrix elements, even due to a misprint, a significant increase in the inconsistency index is reported. The high inconsistency may be alarmed not only at the end of the process of filling in the matrix but also during the completion process. Numerical examples are also provided

Characterization of a novel EAST-negative enteropathogenic E. coli strain implicated in a food-borne outbreak of diarrhoea in adults

YesEnteropathogenic Escherichia coli (EPEC) is usually associated with outbreaks and sporadic cases of severe infantile diarrhoea in the developing world, and less commonly with sporadic cases in developed countries. Very little evidence indicates that EPEC is a food-borne pathogen for adults. In a previous study, two groups of adult travellers became ill, and eae+ E. coli of serogroup O111 was isolated from affected individuals and epidemiologically linked to food consumption. Here the strain responsible was further investigated and characterized as an unusual atypical EPEC. PCR analysis of the designated type isolate showed the presence of the rorf1 and espB genes of the LEE pathogenicity island, which was inserted at the chromosomal selC locus. The isolate was negative for the enteroaggregative E. coli EAST-1 toxin present in other strains of EPEC associated with food-borne outbreaks. The strain adhered sparsely to HEp-2 cell monolayers in a diffuse manner, but fluorescent actin staining demonstrated that it was capable of inducing polymerization of actin at the sites of bacterial attachment. Strain P2583 is the first EAST-negative EPEC to be confirmed as a cause of outbreaks of infection in adults following the consumption of contaminated food or water

On optimal completions of incomplete pairwise comparison matrices

An important variant of a key problem for multi-attribute decision making is considered. We study the extension of the pairwise comparison matrix to the case when only partial information is available: for some pairs no comparison is given. It is natural to define the inconsistency of a partially filled matrix as the inconsistency of its best, completely filled completion. We study here the uniqueness problem of the best completion for two weighting methods, the Eigen-vector Method and the Logarithmic Least Squares Method. In both settings we obtain the same simple graph theoretic characterization of the uniqueness. The optimal completion will be unique if and only if the graph associated with the partially defined matrix is connected. Some numerical experiences are discussed at the end of the paper

FACTORS FOR THRIVING IN LAW ENFORCEMENT

The purpose of this non-experimental and quantitative study was to evaluate the degree to which law enforcement officers perceive themselves as thriving. The sample for this study was convenient, non-probable, and purposive and comprised of 214 law enforcement officers from one large law enforcement agency in the State of Florida. The study’s researcher-constructed survey instrument was determined to be internally consistent and reliable. A one sample t-test was used to assess the statistical significance of study participant mean score response to perceptions of thriving and the results were statistically significant. The use of between-subjects analytic techniques was used to compare the effect exerted by the demographic identifier variables upon perceptions of thriving to show there was no statistically significant difference between gender, current job assignment, years of service, and education level. Multiple linear regression (MLR) and Pearson product-moment correlation coefficient (r) were used to correlate the seven dimensions with the perceptions of overall thriving. The seven dimensions were social support, administrative support, sense of purpose, spirituality, effective training, and physical well-being and all determined to be statistically significant. Multiple linear regression (MLR) was used to identify the two most prominent predictors of overall thriving as social support and effective training. Multiple linear regression (MLR) was used on the two independent variables, personal thriving and professional thriving, to show personal thriving was slightly more robust in predicting overall thriving in law enforcement officers

Carriage of antimicrobial-resistant Escherichia coli and staphylococci in dogs in the community: molecular mechanisms

While previous studies have determined the prevalence of meticillin resistant Staphylococcus aureus (MRSA) and antimicrobial resistant (AMR) Escherichia coli in canine populations, few have included sufficiently large sample sizes and fewer still have characterised the isolates or investigated risk factors that might be associated with their carriage. The main aims of the work presented in this thesis were; to determine the nasal prevalence of MRSA and other AMR staphylococci and the faecal prevalence of AMR E. coli in faeces in the canine population of mainland UK. The study also aimed to characterise the bacteria isolated using molecular techniques in order for comparisons to be made with isolates of human origin, and to determine the presence of potential risk factors associated with faecal carriage of AMR E. coli. These objectives were achieved by carrying out two studies. The first study used frozen canine faecal samples collected during a cross sectional study of a semi-rural community in Cheshire to determine the prevalence of AMR E. coli. The second study collected faecal and nasal swabs from dogs visiting veterinary practices across mainland UK. Antimicrobial resistance of the isolates obtained from both studies were characterised using disc diffusion methods and PCR assays. In addition, isolates collected during the second study were subjected to multi-locus sequence typing and DNA micro array analysis of resistance and virulence genes. For antimicrobial resistant E. coli, risk factors associated with carriage were investigated. The prevalence of MRSA in the canine population was found to be low at 1% and all isolates were identical to EMRSA-15, the main human endemic strain in many UK hospitals. The overall S. aureus prevalence was 7.5%, with a higher prevalence of 11.0% of S. pseudintermedius, in which no meticillin resistance was found. Meticillin resistant coagulase negative Staphylococcus spp. was found in 5.5% of dogs. AMR in the isolates varied between species; however resistance to fusidic acid was consistently high. AMR E. coli was common in both studies (29.0% in community study and 44.8% in nationwide study). Resistance to ampicillin (24.0% and 37.2%), tetracycline (19.7% and 30.0%), trimethoprim (16.9% and 23.8%) and resistance to three or more antimicrobial classes (15.3% and 18.1%) was found to be high in both studies (community and nationwide respectively), while resistance to augmentin, chloramphenicol, ciprofloxacin and nalidixic acid was below 10% in both studies. A variety of genes responsible for resistance to expanded spectrum β-lactams was identified; including blaCTX-M-15 and blacmy2, both of which have previously been identified in humans and dogs. A number of variables were found to be associated with resistance to antimicrobials, with previous prescription of antimicrobials and consumption of raw poultry meat remaining in the final model of more than one resistance outcome. The carriage of MRSA and antimicrobial resistant E. coli could pose a potential problem both in terms of the welfare of the dogs carrying such bacteria as well as the zoonotic potential of the bacteria and resistance determinants

Carriage of antimicrobial resistant Escherichia coli in dogs: prevalence, associated risk factors and molecular characteristics

Resistance to antimicrobials, in particular that mediated by extended spectrum β-lactamases (ESBL) and AmpC β-lactamases are frequently reported in bacteria causing canine disease as well as in commensal bacteria, which could be a potential health risk for humans they come into contact with. This cross-sectional study aimed to estimate the prevalence and investigate the molecular characteristics of ESBL and plasmid encoded AmpC (pAmpC)-producing E. coli in the mainland UK vet-visiting canine population and, using responses from detailed questionnaires identify factors associated with their carriage. Faecal samples were cultured for antimicrobial resistant (AMR), ESBL and pAmpC-producing E. coli. A subset of ESBL and pAmpC-producing isolates were subjected to multi-locus sequence typing and DNA microarray analyses. Multivariable logistic regression analysis was used to construct models to identify risk factors associated with multidrug resistant (MDR, resistance to three or more antimicrobial classes), fluoroquinolone resistant, ESBL and AmpC-producing E. coli. AMR E.coli were isolated from 44.8% (n = 260) of samples, with 1.9% and 7.1% of samples carrying ESBL and pAmpC-producing E. coli, respectively. MDR E. coli were identified in 18.3% of samples. Recent use of antimicrobials and being fed raw poultry were both identified as risk factors in the outcomes investigated. A number of virulence and resistance genes were identified, including genes associated with extra-intestinal and enteropathogenic E. coli genotypes. Considering the close contact that people have with dogs, the high levels of AMR E. coli in canine faeces may be a potential reservoir of AMR bacteria or resistance determinants

<i>Campylobacter jejuni</i>transmission and colonisation in broiler chickens is inhibited by Faecal Microbiota Transplantation

ABSTRACT BACKGROUND Campylobacter jejuni, the most frequent cause of foodborne bacterial infection, is found on around 70% of retail chicken. As such there is a need for effective controls in chicken production. Microbial-based controls such as probiotics are attractive to the poultry industry, but of limited efficacy. Furthermore, as commercially-produced chickens have no maternal contact, their pioneer microbiome is likely to come from the hatchery environment. Early delivery of microbials that lead to a more ‘natural avian’ microbiome may, therefore, improve bird health and reduce susceptibility to C.jejuni colonisation. A faecal microbiota transplant (FMT) was used to transfer a mature cecal microbiome to newly-hatched broiler chicks and its effects on C.jejuni challenge assessed. We used both a seeder-bird infection model that mimics natural bird-to-bird infection alongside a direct-challenge model. We used a 16S rRNA gene sequencing-based approach to characterize the transplant material itself alongside changes to the chicken microbiome following FMT. RESULTS FMT changes the composition of the chicken intestinal microbiome. We observed little change in species richness following FMT compared to untreated samples, but there is an increase in phylogenetic diversity within those species. The most significant difference in the ceca is an increase in Lactobacilli, although not a major component of the transplant material, suggesting the FMT results in a change in the intestinal milieu as much as a direct change to the microbiome. Upon direct challenge, FMT resulted in lower initial intestinal colonisation with C.jejuni. More significantly, in a seeder-bird challenge of infection transmission, FMT reduced transmission and intestinal colonisation until common UK retail age of slaughter. In a repeat experiment, transmission was completely blocked following FMT treatment. Delayed FMT administration at 7 days of-age had limited effect on colonisation and transmission. CONCLUSIONS We show that transfer of a whole mature microbiome to newly-hatched chicks reduces transmission and colonisation of C.jejuni. This indicates that modification of the broiler chick microbiome can reduce intestinal colonisation of C.jejuni to levels projected to lead to lower the human infection rate. We believe these findings offer a way to identify key taxa or consortia that are effective in reducing C.jejuni colonisation and improving broiler gut health

Table 6: Results of changing reference categories of categorical variables included in the final model presented in Table 5.

BACKGROUND. Staphylococci are commensals of the mucosal surface and skin of humans and animals, but have been implicated in infections such as otitis externa, pyoderma, urinary tract infections and post-surgical complications. Laboratory records provide useful information to help investigate these infections. Therefore, the objective of this study was to investigate the burdens of these infections and use multinomial regression to examine the associations between various Staphylococcus infections and demographic and temporal factors among dogs admitted to an academic veterinary hospital in South Africa. METHODS. Records of 1,497 clinical canine samples submitted to the bacteriology laboratory at a veterinary academic hospital between 2007 and 2012 were included in this study. Proportions of staphylococcal positive samples were calculated, and a multinomial logistic regression model was used to identify predictors of staphylococcal infections. RESULTS. Twenty-seven percent of the samples tested positive for Staphylococcus spp. The species of Staphylococcus identified were S. pseudintermedius (19.0%), S. aureus (3.8%), S. epidermidis (0.7%) and S. felis (0.1%). The remaining 2.87% consisted of unspeciated Staphylococcus. Distribution of the species by age of dog showed that S. pseudintermedius was the most common (25.6%) in dogs aged 2 4 years while S. aureus was most frequent (6.3%) in dogs aged 5 6 years. S. pseudintermedius (34.1%) and S. aureus (35.1%) were the most frequently isolated species from skin samples. The results of the multivariable multinomial logistic regression model identified specimen, year and age of the dog as significant predictors of the risk of infection with Staphylococcus. There >8 years of age. Similarly, dogs between 2 8 years of age were significantly more likely to test positive for S. pseudintermedius than those >8 years of age. In addition, dogs 2 4 years of age (RRR D 1.83; 1.09 3.06) were significantly more likely to test positive for S. pseudintermedius compared to those <2 years of age. The risk of infection with S. pseudintermedius or S. aureus was significantly higher in ear canal and skin specimens compared to other specimens. CONCLUSIONS. The findings suggest that S. pseudintermedius and S. aureus were the most commonly isolated species from dogs presented at the study hospital. Age of the dog and the location of infection were significant predictors of infection with both Staphylococcus species investigated. Significant increasing temporal trend was observed for S. pseudintermedius but not S. aureus. This information is useful for guiding clinical decisions as well as future research.https://peerj.comam2017Paraclinical Science

The rank reversal problem in multi-criteria decision making : a literature review

Despite the importance of multicriteria decision-making (MCDM) techniques for constructing effective decision models, there are many criticisms due to the occurrence of a problem called rank reversal. Nevertheless, there is a lack of a systematic literature review on this important subject which involves different methods. This study reviews the pertinent literature on rank reversal, based on 130 related articles published from 1980 to 2015 in international journals, which were gathered and analyzed according to the following perspectives: multicriteria technique, year and journal in which the papers were published, co-authorship network, rank reversal types, and research goal. Thus our survey provides recommendations for future research, besides useful information and knowledge regarding rank reversal in the MCDM field