19 research outputs found
Lichens of six vernal pools in Acadia National Park, ME, USA
Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia National Park and strongly suggests that previous efforts at documenting species at the Park have underestimated its species diversity. More work should be conducted to determine whether a unique assemblage of lichens occurs in association with this unique habitat type
Big Data in Critical Infrastructures Security Monitoring: Challenges and Opportunities
Critical Infrastructures (CIs), such as smart power grids, transport systems,
and financial infrastructures, are more and more vulnerable to cyber threats,
due to the adoption of commodity computing facilities. Despite the use of
several monitoring tools, recent attacks have proven that current defensive
mechanisms for CIs are not effective enough against most advanced threats. In
this paper we explore the idea of a framework leveraging multiple data sources
to improve protection capabilities of CIs. Challenges and opportunities are
discussed along three main research directions: i) use of distinct and
heterogeneous data sources, ii) monitoring with adaptive granularity, and iii)
attack modeling and runtime combination of multiple data analysis techniques.Comment: EDCC-2014, BIG4CIP-201
Detection of Clostridium difficile infection clusters, using the temporal scan statistic, in a community hospital in southern Ontario, Canada, 2006–2011
BACKGROUND: In hospitals, Clostridium difficile infection (CDI) surveillance relies on unvalidated guidelines or threshold criteria to identify outbreaks. This can result in false-positive and -negative cluster alarms. The application of statistical methods to identify and understand CDI clusters may be a useful alternative or complement to standard surveillance techniques. The objectives of this study were to investigate the utility of the temporal scan statistic for detecting CDI clusters and determine if there are significant differences in the rate of CDI cases by month, season, and year in a community hospital. METHODS: Bacteriology reports of patients identified with a CDI from August 2006 to February 2011 were collected. For patients detected with CDI from March 2010 to February 2011, stool specimens were obtained. Clostridium difficile isolates were characterized by ribotyping and investigated for the presence of toxin genes by PCR. CDI clusters were investigated using a retrospective temporal scan test statistic. Statistically significant clusters were compared to known CDI outbreaks within the hospital. A negative binomial regression model was used to identify associations between year, season, month and the rate of CDI cases. RESULTS: Overall, 86 CDI cases were identified. Eighteen specimens were analyzed and nine ribotypes were classified with ribotype 027 (n = 6) the most prevalent. The temporal scan statistic identified significant CDI clusters at the hospital (n = 5), service (n = 6), and ward (n = 4) levels (P ≤ 0.05). Three clusters were concordant with the one C. difficile outbreak identified by hospital personnel. Two clusters were identified as potential outbreaks. The negative binomial model indicated years 2007–2010 (P ≤ 0.05) had decreased CDI rates compared to 2006 and spring had an increased CDI rate compared to the fall (P = 0.023). CONCLUSIONS: Application of the temporal scan statistic identified several clusters, including potential outbreaks not detected by hospital personnel. The identification of time periods with decreased or increased CDI rates may have been a result of specific hospital events. Understanding the clustering of CDIs can aid in the interpretation of surveillance data and lead to the development of better early detection systems
Ion rates in the International Space Station during the December 2006 Solar Particle Event
International audienceSolar Particle Events (SPEs) are a major concern during prolonged space missions. During such events, a large amount of light ions, mostly protons and helium nuclei, are accelerated with enough energy to traverse the spacecraft hull and therefore represent a high hazard for the crew health. The ALTEA particle telescope was collecting continuous data inside the USLab module of the International Space Station (ISS) during most of the December 2006 SPEs. The telescope is able to measure protons and helium respectively in the 42-45 MeV and 42-250 MeV/nucleon energy ranges, heavier ions up to relativistic molybdenum, and to discriminate nuclei for Zr. First measurements of the charged radiation environment inside the USLab during a SPE are presented. The data averaged over the entire SPE week show an increase of the light ion rate (about a factor 1.5 in the energy range of the detector) when compared to quiet Sun conditions. The increase becomes much higher during the SPE climax (December 13 th) reaching a factor 10 (when averaged over three ISS orbits showing the highest activity). The extension of these results beyond the detector range is discussed. Conversely, the rates of ions with Z5 are shown not to change significantly during the SPE week
Toward a Context-Aware Methodology for Information Security Governance Assessment Validation
Conducting a cybersecurity assessment is a central activity in protecting a generic organization from cyber-attacks. Several methods exist in research and industry to assess the security level of an organization, from manual activities to automated attack graphs. Unfortunately, automated approaches fail in taking into account the governance aspect that still need to be evaluated manually by the assessor, introducing possible biases or problems deriving from the level of expertise. In this paper, we provide a methodology to support the assessor in the task of evaluating the coverage of cybersecurity controls coming from technical standards, regulations, internal practices. This is done by providing him/her with a multi-layer model that takes into account several organizational layers, a mapping procedure to tie the security controls to the multi-layer model, and the definition of a validation factor that can be used to possibly refine the level of coverage and to suggest possible layers where evidences should be collected to verify and assess the coverage of a security control. A usage scenario provides an initial validation of our approach based on ISO 27001. Developments of this methodology are on-going toward its application to the support of broader cyber-risk assessment activities through discounting risk factors
Effects of Nordic walking in Alzheimer’s disease: A single-blind randomized controlled clinical trial
Non-pharmacological approaches, including exercise programs, have been proposed to improve cognitive function and behavioral symptoms, such as depression, agitation, or aggression, in the management of patients with Alzheimer's disease (AD). Indeed, physical inactivity is one of the main modifiable risk factors in patients with AD, as well as in the development of cardiovascular diseases and related pathologies.Although Nordic Walking (NW), a particular type of aerobic exercise, is known to benefit the health of aging populations, there is little evidence that patients with AD may benefit from this non-pharmacological treatment. In this context, we performed a pilot study in 30 patients with mild/moderate AD to evaluate whether NW influences different cognitive domains, including executive functions, visual-spatial abilities, and verbal episodic memory. To this aim, 15 patients (Control group, CG) underwent reality orientation therapy, music therapy, motor, proprioceptive and postural rehabilitation, and 15 patients (experimental group, EG) in addition to the activities performed by the CG also had the NW with a frequency of twice a week. Neuropsychological assessments and evaluations of daily activities and quality of life were performed at baseline and after 24 weeks. Twenty-two patients, including 13 in the CG and nine in the EG completed the activity program after 24 weeks. The EG showed a significant improvement in the Frontal Assessment Battery, Rey's auditory Verbal Learning Test Delayed Recall, Raven's Colored Progressive Matrices, and completion time for the Stroop Word-Color Interference test, compared to the CG. NW was able to improve cognitive domains like visual-spatial reasoning abilities, verbal episodic memory, selective attention, and processing speed in AD patients. These results, if confirmed by further studies with a larger number of patients and a longer training period, may prospect NW as a safe and likely useful strategy to slow down cognitive impairment in mild/moderate AD
Evaluation of Short-Term Pacing Effect to Predict Long-Term Response to Cardiac Resynchronization Therapy: The TRAJECTORIES Study
Cardiac resynchronization therapy (CRT) is an effective treatment for chronic symptomatic systolic heart failure with cardiac dyssynchrony, but about 1/3 of patients do not respond favorably to the therapy. We hypothesized that acute modifications of the coronary sinus (CS) pacing cathode movements induced by biventricular pacing may be related to resynchronization process and consequently may carry predictive power on CRT response. A method for the 3D reconstruction of CS lead's pacing cathode trajectory (3DTJ) throughout a cardiac cycle showed that trajectory's geometry suddenly changed in responders (R) upon starting of biventricular pacing, becoming less eccentric and more multi-directional. Our multicenter observational study aimed at evaluating the clinical value of 3DTJ. Out of 119 patients enrolled, 50 have ended follow-up and have been analyzed. Concordance between 3DTJ metrics and response was 82% overall (41/50), 91% in R (31/34), 62% in NR (10/16). The proposed 3DTJ metric showed high sensitivity (91%) with specificity=62%; PPV=84%, NPV=77%. From our data, 3DTJ seems a promising tool to acutely predict CS pacing site-specific response to CRT. Its investigational use as an intra-operatory, real-time guidance for selecting LV pacing sites may open new opportunities for CRT patients' selection and therapy delivery
Characterization of a microDiamond detector in high-dose-per-pulse electron beams for intra operative radiation therapy
Purpose: To characterize a synthetic diamond dosimeter (PTW Freiburg microDiamond 60019) in high dose-per-pulse electron beams produced by an Intra Operative Radiation Therapy (IORT) dedicated accelerator. Methods: The dosimetric properties of the microDiamond were assessed under 6, 8 and 9 MeV electron beams by a NOVAC11 mobile accelerator (Sordina IORT Technologies S.p.A.).The characterization was carried out with dose-per-pulse ranging from 26 to 105 mGy per pulse. The microDiamond performance was compared with an Advanced Markus ionization chamber and a PTW silicon diode E in terms of dose linearity, percentage depth dose (PDD) curves, beam profiles and output factors. Results: A good linearity of the microDiamond response was verified in the dose range from 0.2 Gy to 28 Gy. A sensitivity of 1.29 nC/Gy was measured under IORT electron beams, resulting within 1% with respect to the one obtained in reference condition under 60Co gamma irradiation. PDD measurements were found in agreement with the ones by the reference dosimeters, with differences in R50 values below 0.3 mm. Profile measurements evidenced a high spatial resolution of the microDiamond, slightly worse than the one of the silicon diode. The penumbra widths measured by the microDiamond resulted approximately 0.5 mm larger than the ones by the Silicon diode. Output factors measured by the microDiamond were found within 2% with those obtained by the Advanced Markus down to 3 cm diameter field sizes. Conclusions: The microDiamond dosimeter was demonstrated to be suitable for precise dosimetry in IORT applications under high dose-per-pulse conditions. © 2015 Associazione Italiana di Fisica Medica