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Determination of plant stresses such as infections by plant pathogens is currently dependent on time-consuming and complicated analytical technologies. Here, we report a leaf-attachable chemiresistive sensor array for real-time fingerprinting of volatile organic compounds (VOCs) that permits noninvasive and early diagnosis of plant diseases, such as late blight caused by Phytophthora infestans. The imperceptible sensor patch integrates an array of graphene-based sensing materials and flexible silver nanowire electrodes on a kirigami-inspired stretchable substrate, which can minimize strain interference. The sensor patch has been mounted on live tomato plants to profile key plant volatiles at low-ppm concentrations with fast response (<20 s). The multiplexed sensor array allows for accurate detection and classification of 13 individual plant volatiles with >97% classification accuracy. The wearable sensor patch was used to diagnose tomato late blight as early as 4 days post inoculation and abiotic stresses such as mechanical damage within 1 h.

The article discusses the importance of industrial automation and control system (IACS) cybersecurity to ensure system reliability in various process industries. Topics covered include the development of the Instrumentation, Systems and Automation Society (ISA)/International Electrotechnical Commission (IEC) 62443 standards, the important roles of product suppliers, system integrators and asset owners in all phases of the IACS cybersecurity life cycle, and the ISASecure certification.

Ten polymorphic microsatellite loci for the obligate biotrophic, oomycete pathogen of tobacco, Peronospora tabacina,were identified from a small insert genomic library enriched for GT motifs. Eighty-five percent of the 162 loci identified were composed of dinucleotide repeats, whereas only 4% and 11% were tri-and tetra-nucleotide repeats respectively. About 82% of all the microsatellites were perfect and within the library; only about 7% of the loci were duplicated. Primers were designed for 63 loci; 10 loci were polymorphic, 19 were monomorphic and 34 either failed to amplify or produced ambiguous/inconsistent results. The 10 polymorphic loci were characterized with 44 isolates of P. tabacinacollected from tobacco plants growing in Europe, the Near East and North and South America. The number of alleles per locus was either three or four with a mean of 3.2, and the mean number of genotypes per locus was 3.6. Observed heterozygosity was 0.32–0.95, whereas expected heterozygosity was 0.44–0.69 for these loci. All loci except PT054 did not conform to the Hardy-Weinberg distribution. Polymorphic information content (PIC) for the loci was 0.35–0.69 with a mean of 0.50. These microsatellite loci provide a set of markers sufficient to perform genetic diversity and population studies of P. tabacina,and possibly other species of Peronospora.

Objective.To describe a pseudo-outbreak associated with loose bronchoscope biopsy ports caused by inadequate bronchoscope repair practices by third-party vendors and to alert healthcare personnel to assess bronchoscope repair practices.Design.Outbreak investigation.Setting.A 925-bed tertiary care hospital in Baltimore, Maryland.Patients.Patients who underwent bronchoscopy with certain bronchoscopes after they had been repaired by a third-party vendor.Methods.An epidemiologic investigation was conducted to determine the cause of Pseudomonas putidagrowth in 4 bronchoalveolar lavage (BAL) specimens within a 3-day period in May 2008. All bronchoscopes were inspected, and cultures were obtained from bronchoscopes and the environment. Bronchoscope cleaning and maintenance practices were reviewed. Microbiologic results from BAL specimens and medical records were reviewed to find additional cases.Results.All 4 case patients had undergone bronchoscopy with one of 2 bronchoscopes, both of which had loose biopsy ports. Bronchoscope cultures grew P. putida, Pseudomonas aeruginosa,and Stenotrophomonas.The P. putidastrains from the bronchoscopes matched those from the patients. Specimens from 12 additional patients who underwent bronchoscopy with these bronchoscopes grew P. putida, P. aeruginosa,or Stenotrophomonas.No patients developed clinical signs or symptoms of infection, but 7 were treated with antibiotics. Investigation revealed that the implicated bronchoscopes had been sent to an external vendor for repair; examination by the manufacturer revealed irregularities in repairs and nonstandard part replacements.Conclusions.Third-party vendors without access to proprietary information may contribute to mechanical malfunction of medical devices, which can lead to contamination and incomplete disinfection.Infect Control Hosp Epidemiol2012;33(3):224-229

Background.Healthcare-associated infections (HAIs) result in significant morbidity and mortality. Hand hygiene remains a cornerstone intervention for preventing HAIs. Unfortunately, adherence to hand hygiene guidelines among healthcare personnel is poor.Objective.To assess short- and long-term effects of an infection prevention promotion program on healthcare personnel hand hygiene behaviors.Design.Time series design.SettingOur study was conducted at a tertiary care academic center.Participants.Hospital healthcare personnel.Methods.We developed a multimodal program that included a multimedia communications campaign, education, leadership engagement, environment modification, team performance measurement, and feedback. Healthcare personnel hand hygiene practices were measured via direct observations over a 3-year period by “undercover” observers.Results.Overall hand hygiene compliance increased by 2-fold after full program implementation (P<.001), and this increase was sustained over a 20-month follow-up period (P< .001). The odds for compliance with hand hygiene increased by 3.8-fold in the 6 months after full program implementation (95% confidence interval, 3.53–4.23; P< .001), and this increase was sustained. There was even a modest increase at 20 months of follow up. Hand hygiene compliance increased among all disciplines and hospital units. Hand hygiene compliance increased from 35% in the first 6 months after program initiation to 77% in the last 6 months of the study period among nursing providers (P<.001), from 38% to 62% among medical providers (P<.001), and from 27% to 75% among environmental services staff (P<.001).Conclusions.Implementation of the infection prevention promotion program was associated with a significant and sustained increase in hand hygiene practices among healthcare personnel of various disciplines.Infect Control Hosp Epidemiol2012;33(2):144-151

The article presents an overview of canopy formation (CF) skydiving. According to the author, CF jumpers usually focus their interest in one of two branches, recreational CF or competition. The author says that CF is the only remaining discipline for which the United States Parachute Association (USPA) offers performance-based awards, the 4-Stack, 8-Stack, and Canopy Crest Soloist Awards. New CF jumpers should learn the discipline with an experienced and knowledgeable CF mentor.

Objective.To review the effect of interventions, including a complete restriction in the use of fluoroquinolones (FQs), used to control an outbreak of hospital-onset Clostridium difficileinfection (HO-CDI) caused primarily by the epidemic North American pulsed-field gel electrophoresis type 1 strain.Design.Retrospective cohort and case-control study of all episodes of HO-CDI both before and after 2 interventions.Setting.Community hospital; January 1, 2005, through March 31, 2007.Interventions.Complete, 5-month, facility-wide restriction of fluoroquinolone use, during which a change in the environmental-services contractor occurred.Results.During a 27-month period, 319 episodes of HO-CDI occurred. The hospital-wide mean defined daily doses of antimicrobials decreased 22% after restricting FQ use, primarily because of a 66% decrease in the use of FQs. The interventions were also associated with a significant change in the HO-CDI incidence trends and with an absolute decrease of 22% in HO-CDI cases caused by the epidemic strain (from 66% before the intervention period to 44% during and after the intervention period; P= .02). Univariate analysis revealed that case patients with HO-CDI due to the epidemic strain were more likely than control patients, who did not have diarrhea, to receive a FQ, whereas case patients with HO-CDI due to a nonepidemic strain were not. However, FQ use was not significantly associated with HO-CDI in multivariable analysis.Conclusions.An outbreak of epidemic-strain HO-CDI was controlled at a community hospital after an overall decrease in antimicrobial use, primarily because of a restriction of FQ use and a change in environmental-services contractors. The restriction of FQ use may be useful as an adjunct control measure in a healthcare facilities during outbreaks of epidemic-strain HO-CDI.

Phylogenetic relationships of Phytophthora infestans sensu latoin the Andean highlands of South America were examined. Three clonal lineages (US-1, EC-1, EC-3) and one heterogeneous lineage (EC-2) were found in association with different host species in genus Solanum. The EC-2 lineage includes two mitochondrial (mtDNA) haplotypes, Ia and Ic. Isolates of P. infestans sensu latoEC-2 fit the morphological description of P. infestansbut are different from any genotypes of P. infestansdescribed to date. All isolates of P. infestans sensu latofrom Ecuador were amplified by a P. infestansspecific primer (PINF), and restriction fragment length patterns were identical in isolates amplified with ITS primers 4 and 5. The EC-1 clonal lineage of P. infestans sensu latofrom S. andreanum, S. columbianum, S. paucijugum, S. phureja, S. regularifolium, S. tuberosumand S. tuquerensewas confirmed to be P. infestansbased on sequences of the cytochrome oxidase I (coxI) gene and intron 1 of rasgene. The EC-2 isolates with the Ic haplotype formed a distinct branch in the same clade with P. infestansand P. mirabilis, P. phaseoliand P. ipomoeaefor both coxI and rasintron 1 phylogenies and were identified as the newly described species P. andina. Rasintron 1 sequence data suggests that P. andinamight have arisen via hybridization between P. infestansand P. mirabilis.

The timing of solarization with clear plastic mulch in relation to the planting of pepper and the timing of soil amendment with a bran prill formulation of Gliocladium virens were evaluated for the control of southern blight and the survival of sclerotia of the pathogen Sclerotium rolfsii in bell pepper in the field. Solarization during crop growth increased the incidence of southern blight, and G. virens was not effective under the mulch. In addition, pepper yields were low when the soil was solarized during crop growth. In contrast, the solarization of fallow soil in raised beds for 6 weeks prior to crop growth significantly reduced disease incidence in the pepper crop. In addition, in 2 years, G. virens alone reduced southern blight in non-solarized soils and reduced the survival of sclerotia of S. rolfsii to depths of 30 cm at all locations in soil in both years. These data demonstrate two effective biological control strategies for the management of southern blight in the southeastern US.

Enterotoxigenic Escherichia coli (ETEC) of serotype O6:H16, biotype A, bearing colonization factor antigen II (CFA/II) possesses two distinct coli surface antigens, CS1 and CS3, whereas CFA/II-positive ETEC of serotype O8:H9 manifests only CS3. CS1 has been shown to be fimbrial in nature, but heretofore the morphology of CS3 has not been described. Accordingly, by immune electron microscopy we investigated the morphological characteristics of CS3 on bacterial cells and after purification. CS3 was found to consist of thin (2-nm), flexible, wiry, "fibrillar" fimbriae, visible both on bacteria (O6:H16, biotype A, and O8:H9 strains) and in the pure state. In contrast, CS1 exists as wider (6-nm), rigid fimbriae on the surface of O6:H16, biotype A, strains. By the use of antisera to CS1 and CS3 in immune electron microscopy, immunodiffusion in gel, and immunoblotting techniques, CS1 and CS3 were found to be immunologically as well as morphologically distinct. Six of nine volunteers who developed diarrhea after challenge with an O139:H28 ETEC strain bearing CS1 and CS3 had significant serological rises to purified CS1 and CS3 antigens, suggesting that both antigens are elaborated in vivo, play a role in pathogenesis, and stimulate an immune response.

Enterotoxigenic Escherichia coli (ETEC) isolates from 36 persons with acute traveler's diarrhea from whom no other pathogens were recovered were tested (after no more than three subcultures) for the presence of colonization factor antigens I and II (CFA/I and CFA/II) and type 1 somatic pili. CFA/I or CFA/II was identified in 7 of 10 strains with heat-labile and heat-stable enterotoxins (LT+/ST+), but in only 2 of 12 LT-/ST+ (P less than 0.05) and 0 of 14 LT+/ST- (P less than 0.02) strains. CFA pili were not found among 74 non-enterotoxigenic E. coli strains. Type 1 somatic pili were demonstrable in 42% of the 36 ETEC and in 49% of the 74 non-enterotoxigenic E. coli isolates. The nine ETEC isolates bearing a CFA were serially subcultured on 10 consecutive days and retested for CFA and toxin. After five subcultures only one strain had lost a CFA, but after 10 passages three strains were negative: two lost CFA/I and one lost CFA/II. The strain that lost CFA/II became negative for both LT and ST as well and was found to lack a 48- and a 60-megadalton plasmid. The two strains that lost CFA/I also became negative for ST, but plasmid analysis revealed no plasmid loss. Disappearance of the CFA/I phenotype without loss of a plasmid can be explained by phase variation, as exhibited by type 1 somatic pili, or by rearrangement of base sequences in the CFA/I plasmid genome. If purified pili vaccines are to provide broad-spectrum protection against ETEC diarrhea, the search must be intensified to identify the antigens responsible for adhesion to intestinal mucosa in the many ETEC strains that lack CFA/I and CFA/II.

Previously described GM1 ganglioside enzyme-linked immunosorbent assays (GM1-ELISA) for the detection of Escherichia coli heat-labile enterotoxin (LT) showed sensitivity equal to the Y-1 adrenal cell assay when anti-LT (a reagent not commercially available) was used. However, when antitoxin to immunologically related (commercially available) cholera toxin was substituted, a marked loss in sensitivity occurred. We modified the GM1-ELISA that employed anti-cholera toxin to make it comparable in sensitivity to the Y-1 adrenal cell assay. When five media commonly used for LT production were compared, Mundell's Casamino Acids medium was shown to be significantly superior. Lincomycin (45 micrograms/ml) added to E. coli cultures significantly increased net optical densities in the GM1-ELISA, a direct measure of the amount of LT. Treatment of broth cultures or bacterial cell pellets with polymyxin B or extension of culture time to 48 h also significantly increased net optical density by allowing enhanced release of periplasmic LT. A major innovation involved the direct culture of E. coli strains in GM1-coated wells of microtiter plates followed by ELISA. This direct culture method GM1-ELISA (DCM-GM1-ELISA) saved not only assay time, but also materials and reagents. The net optical densities that result from this assay allow the test to be read visually without a spectrophotometer. Three independent observers read plates with E. coli tested by DCM-GM1-ELISA. Thirty-four of 35 adrenal cell-positive strains (97% sensitivity) and 30 of 30 LT-negative control E. coli strains (100% specificity) were identified by all three observers reading coded plates. The DCM-GM1-ELISA provides a simple, practical and efficient assay for LT for less sophisticated laboratories.

Bacterial outer membrane vesicles (OMVs) perform a variety of functions in bacterial survival and virulence. In mammalian systems, OMVs activate immune responses and are exploited as vaccines. However, little work has focused on the interactions of OMVs with plant hosts. Here, we report that OMVs from Pseudomonas syringaeand P. fluorescensactivate plant immune responses that protect against bacterial and oomycete pathogens. OMV-mediated immunomodulatory activity from these species displayed different sensitivity to biochemical stressors, reflecting differences in OMV content. Importantly, OMV-mediated plant responses are distinct from those triggered by conserved bacterial epitopes or effector molecules alone. Our study shows that OMV-induced protective immune responses are independent of the T3SS and protein, but that OMV-mediated seedling growth inhibition largely depends on proteinaceous components. OMVs provide a unique opportunity to understand the interplay between virulence and host response strategies and add a new dimension to consider in host-microbe interactions.

Several letters to the editor are presented in response to previous articles "Gear and Industry Spotlight--Fly Your Body Introduces Cruise Tracking Suit" in the August 2013 issue and "Safety Check" by Dan Brodsky-Chenfeld in the September 2013 issue, as well as a letter in which the sender talks about the issues in flying the U.S. flag, particularly in demonstrations (demo).

The article discusses skydiving safety issues concerning parachute rigs. Inspection is the most important part of any service job on a rig. But there is little training beyond the initial formal coursework a rigger goes through for his certification aside from self-study. Skydivers should also inspect the rig before every jump at least be able to tell when something is wrong on the system.

Focuses on drug abuse in the workplace. Causes of drug addiction in the workplace; Discussion of education as the key to confronting drug problems at work; Other helpful programs.

The article reports on a canopy formation course in skydiving that was hosted by members of the Leapdogs demonstration team at the Skydive Sebastian drop zone in Florida from September 28 to 30, 2007. It includes an in-depth analysis of various subject matter relevant to the issue, as well as a discussion of the event's implications for skydivers.

A photograph of eight members of Skydivers Over Sixty (SOS) performing a record-breaking 8-way formation skydive in Italy in September 2007 is presented.

The article announces the loss of skydiving equipment that are believed to be stolen from the Skydive Spaceland drop zone in Rosharon, Texas on September 1, 2007.