Securely Launching Virtual Machines on Trustworthy Platforms in a Public Cloud

In this paper we consider the Infrastructure-as-a-Service (IaaS) cloud model which allows cloud users to run their own virtual machines (VMs) on available cloud computing resources. IaaS gives enterprises the possibility to outsource their process workloads with minimal effort and expense. However, one major problem with existing approaches of cloud leasing, is that the users can only get contractual guarantees regarding the integrity of the offered platforms. The fact that the IaaS user himself or herself cannot verify the provider promised cloud platform integrity, is a security risk which threatens to prevent the IaaS business in general. In this paper we address this issue and propose a novel secure VM launch protocol using Trusted Computing techniques. This protocol allows the cloud IaaS users to securely bind the VM to a trusted computer configuration such that the clear text VM only will run on a platform that has been booted into a trustworthy state. This capability builds user confidence and can serve as an important enabler for creating trust in public clouds. We evaluate the feasibility of our proposed protocol via a full scale system implementation and perform a system security analysis

Subjective outcome related to donor site morbidity after sural nerve graft harvesting: a survey in 41 patients

Background: The sural nerve is the most commonly used nerve for grafting severe nerve defects. Our aim was to evaluate subjective outcome in the lower leg after harvesting the sural nerve for grafting nerve defects. Methods: Forty-six patients were asked to fill in a questionnaire to describe symptoms from leg or foot, where the sural nerve has been harvested to reconstruct an injured major nerve trunk. The questionnaire, previously used in patients going through a nerve biopsy, consists of questions about loss of sensation, pain, cold intolerance, allodynia and present problems from the foot. The survey also contained questions (visual analogue scales; VAS) about disability from the reconstructed nerve trunk. Results: Forty-one out of 46 patients replied [35 males/6 females; age at reconstruction 23.0 years (10-72); median (min-max), reconstruction done 12 (1.2-39) years ago]. In most patients [37/41 cases (90%)], the sural nerve graft was used to reconstruct an injured nerve trunk in the upper extremity, mainly the median nerve [19/41 (46%)]. In 38/41 patients, loss of sensation, to a variable extent, in the skin area innervated by the sural nerve was noted. These problems persisted at follow up, but 19/41 noted that this area of sensory deficit had decreased over time. Few patients had pain and less than 1/3 had cold intolerance. Allodynia was present in half of the patients, but the majority of them considered that they had no or only slight problems from their foot. None of the patients in the study required painkillers. Eighty eight per cent would accept an additional sural nerve graft procedure if another nerve reconstruction procedure is necessary in the future. Conclusions: Harvesting of the sural nerve for reconstruction nerve injuries results in mild residual symptoms similar to those seen after a nerve biopsy; although nerve biopsy patients are less prone to undergo an additional biopsy

Interacting effects of insect and ungulate herbivory on Scots pine growth

Most plants are subjected to damage from multiple species of herbivores, and the combined impact on plant growth can be non-additive. Since plant response to herbivores tends to be species specific, and change with repeated damage, the outcome likely depend on the sequence and number of attacks. There is a high likelihood of non-additive effects on plant growth by damage from mammals and insects, as mammalian herbivory can alter insect herbivore damage levels, yet few studies have explored this. We report the growth response of young Scots pine trees to sequential mammal and insect herbivory, varying the sequence and number of damage events, using an ungulate-pine-sawfly system. Combined sawfly and ungulate herbivory had both additive and non-additive effects on pine growth-the growth response depended on the combination of ungulate browsing and sawfly defoliation (significant interaction effect). Repeated sawfly herbivory reduced growth (compared to single defoliation) on un-browsed trees. However, on browsed trees, depending on when sawfly defoliation was combined with browsing, trees exposed to repeated sawfly herbivory had both higher, lower and the same growth as trees exposed to a single defoliation event. We conclude that the sequence of attacks by multiple herbivores determine plant growth response

Impact of smoking and preoperative electrophysiology on outcome after open carpal tunnel release

Background: The aim was to evaluate the influence of smoking and preoperative electrophysiology on the outcome of open carpal tunnel release. Methods: This retrospective observational study evaluated the outcome in 493 patients (531 hands) primary operated for carpal tunnel syndrome. Data were collected from medical records, health evaluations, and QuickDASH questionnaires before surgery and 1 year after. Results: Smokers had a higher QuickDASH score preoperatively as well as postoperatively, but the change in total score did not differ. The odds of having a postoperative QuickDASH score >10 were 2.5 times higher in smoking patients than in non-smoking patients. In 124/493 patients (25%), no clinically significant improvement was seen. Normal and extreme preoperative electrophysiology values were associated with higher postoperative scores. No correlation was found between preoperative QuickDASH scores and preoperative electrophysiology values. Conclusions: Smokers with carpal tunnel syndrome experience more symptoms preoperatively. Smokers have remaining symptoms after surgery. There is no correlation between preoperative QuickDASH scores and preoperative electrophysiology values. Patients with normal or near to normal preoperative electrophysiology results have limited improvement after surgery

Mercury, silver and selenium in serum before and after removal of amalgam restorations: results from a prospective cohort study in Norway

Objective A prospective cohort study on changes of health complaints after removal of amalgam restorations was carried out at the request of the Norwegian Directorate of Health. The aim was to provide and evaluate experimental treatment to patients with health complaints attributed to dental amalgam fillings. Methods Patients (n = 32) with medically unexplained physical symptoms (MUPS), which were attributed to dental amalgam restorations had all their amalgam restorations removed and replaced with other dental restorative materials. Samples of blood were collected before and 1 year after removal of the fillings, and concentration of inorganic mercury (I-Hg), methylmercury (MeHg), silver (Ag) and selenium (Se) in serum was determined by inductively coupled plasma–sector field mass spectrometry. The comparison groups (one with MUPS but without attribution to amalgam [n = 28] and one group of healthy individuals [n = 19]) received no treatment. The participants responded to questionnaires at baseline and at follow-up after 1 and 5 years. Results Concentration of I-Hg and Ag in serum decreased significantly after removal of all amalgam restorations. Concentration of MeHg and Se in serum were not changed. Intensity of health complaints was significantly reduced after amalgam removal, but there were no statistically significant correlations between exposure indicators and health complaints. Conclusions Removal of all amalgam restorations is followed by a decrease of concentration of I-Hg and Ag in serum. The results support the hypothesis that exposure to amalgam fillings causes an increase of the daily dose of both I-Hg and Ag. Even though intensity of health complaints decreased after removal of all amalgam restorations there was no clear evidence of a direct relationship between exposure and health complaints

Validity and responsiveness of GHC-index in patients with amalgam-attributed health complaints

Objective Many patients have medically unexplained physical symptoms (MUPS); some of them attribute their health complaints to dental amalgam fillings. The aim of this study was to assess the validity and responsiveness of General Health Complaints index (GHC-index) for measuring the symptom load in MUPS patients compared to the widely used symptom outcome measure, Giessen Subjective Complaints List (GBB-24). Methods Three outcome measures – GHC-index, GBB-24, and Munich Amalgam Scale (MAS) – were administered at baseline and 12 months after removal of all dental amalgam restorations. The validity and responsiveness of these symptom measures were tested against external anchors: bodily distress syndrome (BDS), SF-36 vitality, and visual analogue scale (VAS). We tested both convergent and known group validities. We also examined the predictive validity and responsiveness to changes for each instrument. Results All the main outcome measures showed evidence of convergent and known group validities. The GHC-index, GBB-24 and MAS were all able to detect the anticipated differences in BDS and Energy. But the GBB-24 was more efficient in discriminating the BDS compared with the GHC-index (relative efficiency: RE = 0.69; 95% CI: 0.41–0.96) and MAS (RE = 0.59; 95% CI: 0.32–0.86). Each main outcome variable revealed good predictive validity for vitality (standardized coefficient: b ≈ 0.71 and R2 ≈ 0.50). Moderate to high sensitivity to change over time was demonstrated, with GHC-index performing better. Conclusion The GHC-index is a valid and responsive instrument for assessing symptom load in MUPS patients attributing their health complaints to amalgam fillings and undergoing amalgam removal.publishedVersio

Dynamic Simulation of Post-Combustion Capture System

AbstractPost-combustion capture, as one of candidate technologies for carbon dioxide emission mitigation, has been employed in the chemical industry to separate CO2 from a gas mixture. However, the largest CO2 emission industry in China is the power industry, where CO2 is mainly released from coal-fired power plants. The study on the dynamic simulation of post-combustion capture system is indispensable for the future implementation of post-combustion capture system on coal-fired power plants, because the output of each coal-fired power plant is controlled by the grid and varies with time in China. Using DYNSIM software, we built a dynamic model for the typical post-combustion capture system, i.e. CO2 absorption/desorption process using aqueous MEA solution. A set of case studies were carried out to investigate the performance of post-combustion capture system. The simulation results show that the flow rate of flue gas and the flow rate of lean solution can greatly influent the stability and the capture ratio of a post- combustion capture system. Therefore, some special control strategies should be designed for them in order to keep the capture system running steadily

Fatal anafylaksi etter tannbehandling

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Bisphenol A in human saliva and urine before and after treatment with dental polymer‐based restorative materials

The aim of this study was to quantify bisphenol A (BPA) concentrations in saliva and urine before and after treatment with dental polymer-based restorative materials to assess if placement of this material is associated with increased BPA levels in saliva and urine. Twenty individuals in need of at least one dental restoration with polymer-based restorative material were included in this study. The participants were instructed to abstain from eating, drinking, and brushing their teeth for at least 10 h prior to sampling. Saliva and urine were collected before and 10 min (saliva only), 1 h, 24 h, and 1 wk after treatment. Samples were stored at 80°C before analyses. BPA in saliva and urine was determined with liquid chromatography/mass spectrometry. Linear mixed effects regression models were used for statistical analyses. There was a statistically significant increase of salivary BPA concentration directly after placement of the dental polymer-based restorations. Following placement, the concentration of BPA decreased exponentially with time. One week after treatment the BPA level in saliva was only marginally higher than before treatment. In urine, no statistically significant change of the BPA concentration was detected after treatment.publishedVersio