Time-domain Physical Unclonable Functions

One can replace one-way functions (also known as hash functions) commonlyfound in cryptography with physical processes, known as physical unclonable functions (PUFs). Optical PUFs have been devised based on the complex response ofscattering media to the spatial wavefront. However, such PUFs are intrinsicallyunpractical for use over larger distances. In this project, we design PUFs with atime-domain scattering response (tPUF), whose readout can be performed over asingle spatial mode, in our case an optical fiber. These tPUFs are networks of microring resonators, whose transfer function is highly complex and vary strongly from realization to realization as a result of manufacturing imperfections. Thesedevices are developed for pulses with a very low number of average photons perpulse which negates any attempts at reading out the pulse shape in transit, therebyeliminating eavesdropping. These PUFs can then be used for a variety of applicationsin asymmetric cryptography, such as proof of identity and secure messaging

Inrichting en effecten van schakelklassen: resultaten van het evaluatieonderzoek schakelklassen in het schooljaar 2007/08

Bestrijding van segregatie in het onderwijs in gemeenten: verkenning van lokaal beleid anno 200

Biomarkers associated with delirium in critically ill patients and their relation with long-term subjective cognitive dysfunction; indications for different pathways governing delirium in inflamed and noninflamed patients

Introduction: Delirium occurs frequently in critically ill patients and is associated with disease severity and infection. Although several pathways for delirium have been described, biomarkers associated with delirium in intensive care unit (ICU) patients is not well studied. We examined plasma biomarkers in delirious and nondelirious patients and the role of these biomarkers on long-term cognitive function.Methods: In an exploratory observational study, we included 100 ICU patients with or without delirium and with ("inflamed”) and without ("noninflamed”) infection/systemic inflammatory response syndrome (SIRS). Delirium was diagnosed by using the confusion-assessment method-ICU (CAM-ICU). Within 24 hours after the onset of delirium, blood was obtained for biomarker analysis. No differences in patient characteristics were found between deliriousand nondelirious patients. To determine associations between biomarkers and delirium, univariate and multivariatelogistic regression analyses were performed. Eighteen months after ICU discharge, a cognitive-failure questionnaire was distributed to the ICU survivors.Results: In total, 50 delirious and 50 nondelirious patients were included. We found that IL-8, MCP-1, procalcitonin (PCT), cortisol, and S100-b were significantly associated with delirium in inflamed patients (n = 46). In the noninflamed group of patients (n = 54), IL-8, IL-1ra, IL-10 ratio Ab1-42/40, and ratio AbN-42/40 were significantly associated with delirium. In multivariate regression analysis, IL-8 was independently associated (odds ratio, 9.0; 95% confidence interval (CI), 1.8 to 44.0) with delirium in inflamed patients and IL-10 (OR 2.6; 95% CI 1.1 to 5.9), and Ab1-42/40 (OR, 0.03; 95% CI, 0.002 to 0.50) with delirium in noninflamed patients. Furthermore, levels of several amyloid-b forms, but not human Tau or S100-b, were significantly correlated with self-reported cognitive impairment 18 months after ICU discharge, whereas inflammatory markers were not correlated to impaired longterm cognitive function.Conclusions: In inflamed patients, the proinflammatory cytokine IL-8 was associated with delirium, whereas in noninflamed patients, antiinflammatory cytokine IL-10 and Ab1-42/40 were associated with delirium. This suggests that the underlying mechanism governing the development of delirium in inflamed patients differs from that in noninflamed patients. Finally, elevated levels of amyloid-b correlated with long-term subjective cognitive-impairment delirium may represent the first sign of a (subclinical) dementia process. Future studies must confirm these results

Psychiatric disorders in children and adolescents presenting with unexplained chronic pain: what is the prevalence and clinical relevancy?

The prevalence of psychiatric disorders among children with unexplained chronic pain (UCP) is high in unselected populations and pain clinics, yet the clinical relevance of these disorders in children referred for unexplained pain is not known. This study assessed the prevalence of clinically relevant psychiatric disorders and their predictors in children referred to a children’s hospital for UCP. Psychiatry morbidity was assessed in 134 children, aged 8–17 years, using the Diagnostic Interview Schedule for Children–parent version (DISC-P) and the Semi-structured Clinical Interview for Children and Adolescents (SCICA). Clinical relevance was determined using a maladjustment criterion of 61 or lower on the Children’s Global Assessment Scale (CGAS). Pain parameters were measured with standardized questionnaires. Results were analysed by logistic regression. According to the DISC-P, 21% of the children had clinically relevant psychiatric disorders, predominantly anxiety disorders (18%). According to the SCICA, 28% of the children had clinically relevant psychiatric disorders, consisting of anxiety, affective, and disruptive disorders (12, 19, and 9%, respectively). Headache (compared to musculoskeletal pain) was an independent clinical predictor of psychiatric morbidity (OR = 3.10; 95% CI 1.07–8.92, p = 0.04/adjusted OR 2.99; 95% CI 1.02–8.74, p = 0.04). In conclusion, clinically relevant psychiatric disorders are common among children and adolescents referred for UCP. Adding a child psychiatrist assessment, treatable affective and disruptive disorders become identifiable. Children with an additional risk are those presenting with headache

Construction of a secondary metabolite deficient penicillium chrysogenum strain as a generic production host for secondary metabolites

Secondary metabolism of the filamentous fungus Penicillium chrysogenum has been intensively explored to relate specific secondary metabolites to their respective biosynthetic gene clusters. We have removed the three main biosynthetic gene clusters that specify the antibiotic penicillin, the mycotoxin roquefortine and the yellow pigment chrysogine, in order to generate a secondary metabolite deficient strain. This strain produces increased levels of other secondary metabolites some of which have not been detected before. The strain and its biosynthetic potential will now be further investigated for the expression of novel enzymes and biosynthetic pathways to make the synthesis of antibiotics and other secondary metabolites more specific and efficient. Using structure guided protein engineering new enzymes will be further designed and optimized for the construction of a newly designed biosynthetic pathway into a novel platform strain

The prevalence of axial spondyloarthritis in the UK: a cross-sectional cohort study

Background: Accurate prevalence data are important when interpreting diagnostic tests and planning for the health needs of a population, yet no such data exist for axial spondyloarthritis (axSpA) in the UK. In this cross-sectional cohort study we aimed to estimate the prevalence of axSpA in a UK primary care population. Methods: A validated self-completed questionnaire was used to screen primary care patients with low back pain for inflammatory back pain (IBP). Patients with a verifiable pre-existing diagnosis of axSpA were included as positive cases. All other patients meeting the Assessment of SpondyloArthritis international Society (ASAS) IBP criteria were invited to undergo further assessment including MRI scanning, allowing classification according to the European Spondyloarthropathy Study Group (ESSG) and ASAS axSpA criteria, and the modified New York (mNY) criteria for ankylosing spondylitis (AS). Results: Of 978 questionnaires sent to potential participants 505 were returned (response rate 51.6 %). Six subjects had a prior diagnosis of axSpA, 4 of whom met mNY criteria. Thirty eight of 75 subjects meeting ASAS IBP criteria attended review (mean age 53.5 years, 37 % male). The number of subjects satisfying classification criteria was 23 for ESSG, 3 for ASAS (2 clinical, 1 radiological) and 1 for mNY criteria. This equates to a prevalence of 5.3 % (95 % CI 4.0, 6.8) using ESSG, 1.3 % (95 % CI 0.8, 2.3) using ASAS, 0.66 % (95 % CI 0.28, 1.3) using mNY criteria in chronic back pain patients, and 1.2 % (95 % CI 0.9, 1.4) using ESSG, 0.3 % (95 % CI 0.13, 0.48) using ASAS, 0.15 % (95 % CI 0.02, 0.27) using mNY criteria in the general adult primary care population. Conclusions: These are the first prevalence estimates for axSpA in the UK, and will be of importance in planning for the future healthcare needs of this population. Trial registration: Current Controlled Trials ISRCTN7687321

Relationship between duration of brain death and hemodynamic (in)stability on progressive dysfunction and increased immunologic activation of donor kidneys

Relationship between duration of brain death and hemodynamic (in)stability on progressive dysfunction and increased immunologic activation of donor kidneys.BackgroundConsistent difference in graft survival after renal transplantation has been shown when cadaveric transplants are compared to the living related donor situation, in favor of the latter. Recently, evidence has been put forward that brain death has significant effects on the donor organ quality. In this study, we aimed to assess the relation between brain death–induced hemodynamic instability in combination with the duration of brain death on the function and immunogenicity status of potential donor kidneys.MethodsIn Wistar rats, short-term (1hour) or long-term (6hours) brain death in the presence or absence of hemodynamic stability was applied. Sham-operated rats served as controls (1hour and 6hours). Organ function was studied by monitoring serum creatinine, lactate dehydrogenase (LDH), lactate, and total protein content. Expression of cell adhesion molecules [intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)] and the influx of leukocytes in the kidney assessed the immunologic status of the kidney.ResultsProgressive organ dysfunction was most pronounced in hemodynamically unstable brain-dead donors reflected by increased serum creatinine levels. Regardless of hemodynamic status, a progressive inflammatory activation by cell adhesion molecule expression and an influx of leukocytes could be observed in kidneys of brain-dead rats compared with nonbrain-dead controls.ConclusionBrain death causes progressive kidney dysfunction. Also, inflammatory responses reflecting tissue injury are caused by brain death. When hemodynamic instability in the brain-dead donor is not corrected, kidney dysfunction is enhanced and immune activation occurs faster and is more profound. The observed changes may predispose the graft for additional ischemia/reperfusion injury during the transplant process and hence accelerate rejection of the graft after transplantation

Pressure cooker ownership and food security in Aurangabad, India

Objective: To explore associations between household food security and home gardening, use of soya and pressure cooker ownership in low-income households affected by HIV/AIDS in Aurangabad, India. Design: Cross-sectional pilot study which assessed household food security using the validated US Department of Agriculture’s food security core-module questionnaire. Questions were added to explore household environment, education, occupation, home gardening, use of soya and pressure cooker ownership. Households with very low v. low food security were compared using logistic regression analysis, controlling for confounding by socio-economic status. Setting: Aurangabad is an urban setting situated in a primarily agricultural dependent area. The study was carried out in 2008, at the peak of the global food crisis. Subjects: Adult caregivers of children affiliated with the Network of People Living with HIV/AIDS in Aurangabad. Results: All except for one of 133 households were identified as food insecure (99?2 %). Of these households, 35?6% had to cut size or skip a meal in the past 30 d. Households that cut meal size due to cooking fuel shortages were more likely to have very low food security (OR54?67; 95% CI 1?62, 13?44) compared with households having no cooking fuel shortages. Owning a pressure cooker was shown to be protective against very low food security after controlling for confounding by socio-economic status (OR50?27; 95% CI 0?11, 0?64). Conclusions: Only pressure cooker ownership showed a protective association with low household food security. Pressure cookers save household fuel costs. Therefore, future interventions should explore pressure cookers as a sustainable means of improving household food securit

Intramuscular EMG versus Surface EMG of Lumbar Multifidus and Erector Spinae in Healthy Participants

Study Design: Cross-sectional design. Objective: The aim of this study was to investigate the correlation between intramuscular EMG (iEMG) and surface EMG (sEMG) from lumbar multifidus and erector spinae muscles during (submaximal) voluntary contraction tests in healthy participants. Summary of Background Data: Low back muscle function is a key component in the stability of the lumbar spine in which an important role is attributed to the lumbar multifidus (LM). Impairments in this stabilization system are held responsible for (chronic) low back pain. LM function can be measured by iEMG and sEMG; however, in earlier studies, results from iEMG and sEMG were inconsistent. Methods: Fifteen healthy adults were included. The intervention consisted of five clinical tests: resting, submaximal contraction tests of the lower back, abdominal contraction, and a biofeedback test in which LM and erector spinae (ES) activities were compared by iEMG and sEMG. Correlations were calculated with regard to original signal, co-contraction ratio, and cross-talk ratio. Correlation coefficients for each combination of iEMG and sEMG signals were calculated, to identify original signal (i.e., activity of only the targeted muscle) and possible cross-talk. Correlations >0.75 were considered as good concurrent validity. Results: The original signals of LM showed fair to high correlation coefficients (r: 0.3–0.8). Co-contraction of LM and ES was observed during all tests, but iEMG shows more variation in the correlations (r: 0.1–0.8) compared to sEMG (r: 0.3–0.8). Significant cross-talk was observed in all tests, particularly during the biofeedback test of iEMGESversus sEMGLM and iEMGLMversus sEMGES (r = 0.8). Conclusion: Surface EMG of ES and LM are no adequate representation of LM and ES activity measured by iEMG because of moderate/high cross-talk and co-contractions. Clinical tests that aim to assess LM activity do not represent isolated LM activity. This should be taken into account in future clinical studies