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Internet of Things (IoT) popularity and complexity has grown at an accelerating rate. As a result, IoT security is more critical than ever before. Many services attempt to simplify the bottlenecks of IoT infrastructure, development and deployment which previously fell to developers. However, these services are often proprietary and insecure. In this paper, we explore an alternative IoT service model that uses Docker to securely bootstrap an IoT network running on 3 Raspberry Pis. This service uses containerization technology with Linux to abstract architectural details, software update mechanisms, and network security away from the developer. Devices authenticate and communicate with a remote server using private key cryptography, while OTA updates are delivered via the Docker registry. We show that this model satisfies modern security standards of lightweight technology and fulfills expectations of a deployment platform.

Human norovirus (NoV) is the leading cause of foodborne illness in the United States and Canada. Wastewater treatment plant (WWTP) effluents impacting bivalve mollusk-growing areas are potential sources of NoV contamination. We have developed a meta-analysis that evaluates WWTP influent concentrations and log 10 reductions of NoV genotype I (NoV GI; in numbers of genome copies per liter [gc/liter]), NoV genotype II (NoV GII; in gc/liter), and male-specific coliphage (MSC; in number of PFU per liter), a proposed viral surrogate for NoV. The meta-analysis included relevant data (2,943 measurements) reported in the scientific literature through September 2013 and previously unpublished surveillance data from the United States and Canada. Model results indicated that the mean WWTP influent concentration of NoV GII (3.9 log 10 gc/liter; 95% credible interval [CI], 3.5, 4.3 log 10 gc/liter) is larger than the value for NoV GI (1.5 log 10 gc/liter; 95% CI, 0.4, 2.4 log 10 gc/liter), with large variations occurring from one WWTP to another. For WWTPs with mechanical systems and chlorine disinfection, mean log 10 reductions were −2.4 log 10 gc/liter (95% CI, −3.9, −1.1 log 10 gc/liter) for NoV GI, −2.7 log 10 gc/liter (95% CI, −3.6, −1.9 log 10 gc/liter) for NoV GII, and −2.9 log 10 PFU per liter (95% CI, −3.4, −2.4 log 10 PFU per liter) for MSCs. Comparable values for WWTPs with lagoon systems and chlorine disinfection were −1.4 log 10 gc/liter (95% CI, −3.3, 0.5 log 10 gc/liter) for NoV GI, −1.7 log 10 gc/liter (95% CI, −3.1, −0.3 log 10 gc/liter) for NoV GII, and −3.6 log 10 PFU per liter (95% CI, −4.8, −2.4 PFU per liter) for MSCs. Within WWTPs, correlations exist between mean NoV GI and NoV GII influent concentrations and between the mean log 10 reduction in NoV GII and the mean log 10 reduction in MSCs.

Over the past 15 years, hepatitis E virus (HEV), norovirus (NoV), and rotavirus (RV) have been hypothesized to be potentially zoonotic; swine and pork have been suggested as possible human infection sources for all 3 viruses. Our objective was to estimate HEV, NoV, and RV prevalence and load on Canadian retail pork chops and livers. Using the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) sampling platform, pork livers (n = 283) and chops (n = 599) were collected, processed, and assayed for the 3 viruses by four collaborating federal laboratories using validated real time reverse transcriptase polymerase chain reactions (qRT-PCR). Follow-up qRT-PCR estimating viral load in genomic copies/g was followed by nested classical RT-PCR and isolate sequencing of a partial segment of the ORF2 gene. Local alignments were performed using MUSCLE (Multiple Sequence Comparison by Log-Expectation); a phylogenetic tree was created. Twenty-five livers and 6 chops were classified ‘positive’ (thresholds for viral RNA detected in both replicates of the assay) or ‘suspect’ (thresholds detected in one of two replicates) for HEV. Follow-up qRT-PCR detected HEV on 16 livers, 0 chops, and nested classical RT-PCR, on 14 livers and 0 chops. Initial qRT-PCR classified 12 chops ‘suspect’ for NoV. Follow-up qRT-PCR detected viral RNA on only one sample with thresholds greater than 40 in both replicates. No amplicon was yielded, and therefore no isolate was sequenced from this sample. Partial ORF2 genes from 14 HEV isolates were sequenced, and compared via sequence identity and phylogenetic analysis with selected human case isolates listed in NCBI-GenBank. Overall, HEV prevalence on retail pork was comparable with other published reports.

In this paper we analyze the effects of the real exchange rate volatility on South Africa’s trade flows with the European Union over the period 1980 to 2009. Our study uses quarterly trade flows on South Africa’s exports and imports and utilizes the bounds testing approach to cointegration, and error-correction model. Our results reveal that imports depend positively on the levels of domestic economic activity and foreign exchange reserves but negatively on relative prices and exchange rate volatility. In addition, exports depend positively on the levels of foreign economic activity but negatively on relative prices and exchange rate volatility. Furthermore, the exchange volatility exerts mixed effects in the short-run and in the long-run.

Aims: To demonstrate that produce rinsates used for RT-qPCR detection of foodborne viruses may cause significant PCR inhibition and propose a means to reduce its impact on sensitivity. Methods and Results: Here, it is shown that rinsing and concentration from spinach and precut lettuce have the potential to generate RNA extracts that are inhibitory to RT-qPCRs assembled from commercial kits for the detection of norovirus GII (NoV GII), hepatitis A virus (HAV), hepatitis E virus (HEV), rotavirus (RV) and feline calicivirus (FCV) as sample process control. It is further shown that the addition of bovine serum albumin (BSA) to those reactions restored a positive signal in all cases. The effect of BSA was dependent upon the primer/probe combination. Moreover, two of the detection systems (FCV and HAV) strongly benefited from the addition of BSA even in the absence of PCR inhibitors. Conclusions: BSA was shown to restore positive signals in five different RT-qPCR systems that were otherwise completely inhibited by produce rinsate extracts. It is therefore suggested to consider the addition of BSA to RT-qPCRs for the detection of foodborne viruses when inhibition is observed. Significance and Impact of the Study: This study clearly demonstrates the potency of PCR inhibitors generated during routine virus concentration from produce and that it can be alleviated by the addition of BSA to the RT-qPCRs. Although used elsewhere, the addition of BSA to PCRs is not a common practice in this growing field of research.

Plant potyvirus RNAs have a virus protein covalently attached at their 5′-end: the VPg (virus protein genome-linked). In part because of its position at the 5′end of the virus RNA, the VPg has been speculated to play a role in virus translation and replication. We report that the VPg of Turnip mosaic virus (TuMV) interacts with, and does not disrupt, the translation initiation complex eIF(iso)4E-eIF(iso)4G. The purification of VPgPro or 6K2VPgPro by affinity chromatography from infected plant tissue also led to the recovery of eIF(iso)4G. The cap analogue m 7 GTP competed with the binding of VPg to both eIF(iso)4E and the eIF(iso)4E-eIF(iso)4G complex. This suggested that the viral VPg bound to the translation initiation complex but that interaction did not result in disassociation of the subunits but rather in competition for the binding of the 5′ cap structure. This would result in decreased affinity of the translation initiation machinery for capped cellular mRNAs.

Campylobacter is the most frequent cause of bacterial gastroenteritis in Canada, and the illness is commonly associated with poultry consumption. Whereas Canadian retail poultry is often contaminated with campylobacters, studies on the prevalence of this organism are inconsistent due to variability in sampling and microbiological methodology. To determine the current microbiological status of Canadian poultry, and to evaluate two commonly used microbiological methods, 348 raw poultry samples were collected at retail across Canada over a period of 3 years (2007 to 2010) and were analyzed for the presence of thermophilic Campylobacter species. The overall prevalence of Campylobacter spp. was found to be 42.8% by a combination of the two testing methods, with 33.9% of the samples positive for C. jejuni, 3.7% of the samples positive for C. coli, and 5.2% of the samples positive for both. Variability in Campylobacter spp. prevalence was observed in samples obtained from different regions across Canada and from poultry with or without skin, but this was not statistically significant. In co-contaminated samples, C. jejuni was preferentially recovered from Preston agar compared with mCCDA and Campy-Cefex agar, with an increase in recovery of C. coli on all selective media after 48 h of enrichment. A subset of 214 of the poultry rinses were analyzed by both Health Canada's standard method, MFLP-46 (enrichment in Park and Sanders broth), and a second method requiring enrichment in Bolton broth. Significantly more positive samples were obtained with the MFLP-46 method (40.6%) than with the alternate method (35.0%). This improved recovery with MFLP-46 may be due to the omission of cycloheximide from this method. These results demonstrate that determination of prevalence of Campylobacter spp. on poultry products may be significantly impacted by the choice of microbiological methods used. Canadian poultry continues to be a source of exposure to Campylobacter spp.

The interaction between the viral protein linked to the genome (VPg) of turnip mosaic potyvirus (TuMV) and the translation eukaryotic initiation factor eIF(iso)4E of Arabidopsis thaliana has previously been reported. eIF(iso)4E binds the cap structure (m 7 GpppN, where N is any nucleotide) of mRNAs and has an important role in the regulation in the initiation of translation. In the present study, it was shown that not only did VPg bind eIF(iso)4E but it also interacted with the eIF4E isomer of A. thaliana as well as with eIF(iso)4E of Triticum aestivum (wheat). The interaction domain on VPg was mapped to a stretch of 35 amino acids, and substitution of an aspartic acid residue found within this region completely abolished the interaction. The cap analogue m 7 GTP, but not GTP, inhibited VPg-eIF(iso)4E complex formation, suggesting that VPg and cellular mRNAs compete for eIF(iso)4E binding. The biological significance of this interaction was investigated. Brassica perviridis plants were infected with a TuMV infectious cDNA (p35Tunos) and p35TuD77N, a mutant which contained the aspartic acid substitution in the VPg domain that abolished the interaction with eIF(iso)4E. After 20 days, plants bombarded with p35Tunos showed viral symptoms, while plants bombarded with p35TuD77N remained symptomless. These results suggest that VPg-eIF(iso)4E interaction is a critical element for virus production.

Torque teno viruses (TTV) are widespread in humans, swine as well as in several other animal species. In market ready swine, the reported prevalence ranges between 11% and 100%. Through a national retail sampling plan from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) program, 283 and 599 liver and pork chop samples, respectively, were collected over a 12-month period from commercial establishments in 5 selected geographical regions of Canada to assess the presence of Torque teno sus viruses (TTSuVs) in these products. TTSuVs were detected in 97.9% of pork chops with viral loads ranging between 1×10(4) and 9.9×10(5) genomic copies (gc)/g and 98.6% of liver samples with viral loads ranging from 1×10(5) to 9.9×10(6) gc/g. A selection of 20 positive samples (10 pork chop and 10 liver) from the 5 geographical regions were further tested for the production, of a 305bp fragment for TTSuV1 and a 253bp fragment for TTSuV2 in the non-coding region. TTSuV1 was present in all 10 liver and 10 pork chops samples while TTSuV2 was detected in 10 liver and 9 pork chop samples. Two different TTSuV1 sequences were simultaneously detected from 5 of 20 samples and 2 different TTSuV2 sequences were detected from 6 of 19 samples. The omnipresence of TTSuVs in commercial pork samples may allow its use as a viral indicator to monitor the effectiveness of cleaning and disinfecting process in slaughtering, cutting, slicing and packaging facilities.

Background Noroviruses (NoVs) are the leading cause of infectious gastroenteritis worldwide. Real-time reverse transcription PCR (real-time RT-PCR) is the preferred method of NoV detection for the majority of testing laboratories. Although the accepted target region for molecular detection assays is the conserved ORF1/ORF2 junction, multiple variations have been published with differences in primers, probes, reagents, multiplexing, etc. Objectives We assessed the detection limit for GII.4 NoV real-time RT-PCR assays as well as the ability to detect the non-GII.4 NoV genotypes in each participating laboratory. Study design A panel of 25 RNA samples was circulated to 18 testing laboratories for comparison of their real-time RT-PCR procedures for NoV detection. Results Multiple protocols with slight differences in reagents or conditions successfully detected 10 genome equivalents or fewer of NoV per reaction. Multiplex procedures were significantly associated ( p = 0.04) with false negative results, particularly for a GI.2 strain. Sensitive detection was associated with false positive results ( p = 0.03). Conclusions Overall, the data indicate that comparable results are produced under slightly different assay conditions.

Aims: The aim of this study was to compare the performance of four TaqMan RT-PCR assays with a commonly used nested RT-PCR and to include the Feline calicivirus (FCV) as an internal control. Methods and Results: RNA extracted from 87 swine faecal samples and 103 swine blood samples was subjected to different detection systems. Faecal samples naturally contaminated with Hepatitis E virus (HEV) and negative samples were artificially inoculated with 3AE2 · 10 3 PFU of FCV. Detection results obtained on faecal and plasma samples were 35AE6% and 4AE9% with the nested RT-PCR assay, 8AE0% and 0%, 0% and 0%, 13AE8% and 0% and 36AE8% and 3AE9% with TaqMan systems A, B, C and D respectively. The Ct means obtained with the multiplex TaqMan assay were 30AE11 and 30AE43 for the detection of FCV with HEV contaminated samples and negative samples. Conclusions: The TaqMan system D was more suitable for the detection of swine HEV strains than the three others and FCV was integrated successfully as an internal control. Significance and Impact of the Study: FCV was demonstrated as an efficient control to monitor the RNA extraction process and HEV amplification procedure in a multiplex HEV ⁄ FCV TaqMan assay. This control would be helpful in limiting false negative results.

The pharmacokinetics of oral diltiazem were studied in 10 patients with chronic renal failure not requiring dialysis and in five healthy volunteers after a single dose of 120 mg. We found that patients with chronic renal failure had lower amounts of unchanged diltiazem and of its main metabolite (MA) in urine and a trend to have slightly higher values of plasma concentration. Since the terminal elimination phase is not affected by chronic renal failure we conclude that this trend is probably the result of alterations in the volume of distribution of diltiazem in these patients.

The pharmacokinetics of diltiazem were studied in seven patients with chronic renal failure (CRF) not requiring dialysis and in three healthy volunteers after a rapid i.v. infusion of 20 mg. Mean plasma concentrations at the end of infusion were 3.15 times higher in patients with CRF than in healthy volunteers. From 0.5 to 12 h post-infusion, the difference remained between 25 per cent and 73 per cent. Mean AUC0-infinity was statistically greater in patients than in volunteers while mean V area, CLtot, and CLren were statistically lower. The t1/2 alpha and t1/2 beta values were not significantly (p greater than 0.05) different between patients and volunteers. Renal excretion was statistically more important in volunteers (6.6 per cent of the dose) than in patients (1.2 per cent of the dose). We therefore conclude that CRF does not influence t1/2 beta of diltiazem but it interferes with the extent and possibly the rate of its extravascular distribution. That could result in transient high plasma concentrations after rapid i.v. infusion.