Anschläge in Timor-Leste : Gefahr für die junge Demokratie?

Different types of X-ray equipment are used in dental radiology, such as intra-oral, panoramic, cephalometric, cone-beam computed tomography (CBCT) and multi-slice computed tomography (MSCT) units. Digital receptors have replaced film and screen-film systems and other technical developments have been made. The radiation doses arising from different types of examination are sparsely documented and often expressed in different radiation quantities. In order to allow the comparison of radiation doses using conventional techniques, i.e. intra-oral, panoramic and cephalometric units, with those obtained using, CBCT or MSCT techniques, the same units of dose must be used. Dose determination should be straightforward and reproducible, and data should be stored for each image and clinical examination. It is suggested here that air kerma-area product (PKA) values be used to monitor the radiation doses used in all types of dental examinations including CBCT and MSCT. However, for the CBCT and MSCT techniques, the estimation of dose must be more thoroughly investigated. The values recorded can be used to determine diagnostic standard doses and to set diagnostic reference levels for each type of clinical examination and equipment used. It should also be possible to use these values for the estimation and documentation of organ or effective doses. This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Radiation Protection Dosimetry following peer review. The definitive publisher-authenticated version: Ebba Helmrot and Anne Thilander Klang, METHODS FOR MONITORING PATIENT DOSEIN DENTAL RADIOLOGY, 2010, Radiation Protection Dosimetry, (139), 1-3, 303-305.is available online at: http://dx.doi.org/10.1093/rpd/ncq095Copyright: Oxford University Presshttp://www.oxfordjournals.org

Anschläge in Timor-Leste: Gefahr für die junge Demokratie?

"Am 11. Februar wurden auf Präsident José Ramos-Horta und Ministerpräsident Xanana Gusmao Anschläge verübt. Beide überlebten, Ramos-Horta wurde jedoch schwer verletzt. Sechs Jahre nach seiner Unabhängigkeit hat Timor-Leste (bis 2002: Osttimor) auf dem Weg zu einer stabilen Demokratie erneut einen Rückschlag erlitten: Die Angriffe auf Ramos-Horta und Gusmao machen deutlich, dass trotz eines Regierungswechsels 2007 drängende Probleme der Postkonfliktgesellschaft nicht gelöst wurden. Die blutige Vergangenheit Timor-Lestes wirkt bis heute nach: Die Gesellschaft ist von der Gewalt der letzten Jahrzehnte traumatisiert, ihre politische Führung zerstritten. Politik und Gesellschaft müssen lernen, Konflikte gewaltfrei zu lösen. Dringend geboten ist eine grundlegende Reform des Sicherheitssektors: Armee und Polizei müssen professionalisiert und der Instrumentalisierung durch einzelne Politiker entzogen werden. Erste Schritte in diese Richtung wurden bereits unternommen und sollten konsequent weiterverfolgt werden. Der Schlüssel für eine stabile und demokratische Entwicklung liegt in der Stärkung der staatlichen Institutionen und insbesondere des Justizwesens: Aufgrund mangelnder personeller und finanzieller Ausstattung der Gerichte ist die Strafverfolgung unzureichend. Timor-Leste ist das ärmste Land Asiens: Aus der Armut speisen sich Frustration und Unzufriedenheit einer Bevölkerung, die rasant wächst. Nur wenn es gelingt, die Lebensbedingungen in kurzer Zeit zu verbessern, hat die Demokratie eine Chance. Die gescheiterten Anschläge sind ein Weckruf für alle Verantwortlichen. Das Ende des 'Rebellenführers' Reinado bietet die Chance, die Sicherheitsprobleme des Landes zu lösen und die Staatskrise von 2006 zu überwinden." (Autorenreferat

Mesoporous Y zeolite through ionic liquid based surfactant templating

New surfactant molecules based on ionic liquids, such as [C(16)MIm]Cl and [C16MPy]Cl were employed in the rearrangement of Y zeolite to introduce mesopores of different morphologies. We evidence that the templating efficiency of these ionic liquids is identical as for the classically used ammonium based surfactant (CAC) in the synthesis of siliceous MCM-41. Yet, their templating behavior differs importantly when used in the surfactant templating approach to produce mesoporous Y zeolite. This finding indicates that the micellization ability of these surfactants within the zeolite confined spaces differs to the one in solution and hence has a major impact on the textural properties of the final zeolite phase. Hierarchical porous zeolite Y with novel textural properties could be disclosed. (C) 2015 Elsevier Inc. All rights reserved.This work was supported by CAPES through a Young Talent Award (058/2012). Authors thank Otelo J. Machado for DRX analysis and the CNANO facility for TEM images.Sachse, A.; Wuttke, C.; Díaz Morales, UM.; Oberson De Souza, M. (2015). Mesoporous Y zeolite through ionic liquid based surfactant templating. Microporous and Mesoporous Materials. 217:81-86. doi:10.1016/j.micromeso.2015.05.049S818621

The impact of working memory and the "process of process modelling" on model quality: Investigating experienced versus inexperienced modellers

A process model (PM) represents the graphical depiction of a business process, for instance, the entire process from online ordering a book until the parcel is delivered to the customer. Knowledge about relevant factors for creating PMs of high quality is lacking. The present study investigated the role of cognitive processes as well as modelling processes in creating a PM in experienced and inexperienced modellers. Specifically, two working memory (WM) functions (holding and processing of information and relational integration) and three process of process modelling phases (comprehension, modelling, and reconciliation) were related to PM quality. Our results show that the WM function of relational integration was positively related to PM quality in both modelling groups. The ratio of comprehension phases was negatively related to PM quality in inexperienced modellers and the ratio of reconciliation phases was positively related to PM quality in experienced modellers. Our research reveals central cognitive mechanisms in process modelling and has potential practical implications for the development of modelling software and teaching the craft of process modelling

An Instrument to Enable Identification of Anthropogenic CO2 Emissions Using Concurrent CO Measurements

We have developed an instrument concept that will enable the measurement of CO from the top of the atmosphere to the Earth's surface with very high sensitivity and at the high spatial and temporal resolutions required by the NRC Decadal Survey mission Active Sensing of Carbon Dioxide (CO2) over Nights, Days and Seasons (ASCENDS). We are developing an innovative CO sensor that will enable the ASCENDS mission to differentiate between anthropogenic and natural sources and sinks of global carbon. The NRC Decadal Survey places particular emphasis on retrieving CO information for the planetary boundary layer. Measurement made using both the 2.3 micron and 4.7 micron channels are needed to achieve the sensitivity required in the lower atmosphere where the degree of CO - CO2 correlation is indicative of anthropogenic sources of CO2. Measurements made using only the 4.7 micron channel cannot provide sufficient sensitivity to CO in the very lowest layers of the atmosphere. The fundamental method we use is Gas Filter Correlation Radiometry (GFCR), a highly successful technique used in other airborne and space-based missions for detecting trace species in the Earth's atmosphere. Our version of GFCR overcomes many of the limitations encountered by prior and existing instruments, allowing us to measure weak signals from small targets very quickly and with extremely high specificity by employing a new dual beam radiometer concept using a focal plane array. Our design will provide a means to make the desired CO measurements for the ASCENDS mission. A simple change in gas filter cell contents would allow the same hardware to measure CH4 with high precision under the nominal ASCENDS mission spatial and temporal constraints. All critical components in the sensor design are mature, many subsystems tested, and the system has been extensively modeled, bringing it to a present Technology Readiness Level (TRL) of 3 (though some individual components are at TRLs 6-9). We are presently developing critical components for the new spectrometer and advancing our understanding of the measurement requirements for both CO and CH4. This new GFCR technique/sensor will enable measurements of trace gases with high sensitivity while maintaining the inherent robustness and simplicity of the more traditional radiometer hardware. Initial estimates of cost/risk of a spacebased 2-channel GFCR indicate that our design is extremely cost effective and will fit within existing ASCENDS mission budget constraints as determined by the NRC Decadal Survey and a NASA-sponsored mission study

Discrete element modeling of aeolian-like morphologies on comet 67P/Churyumov-Gerasimenko

Context: Even after the Rosetta mission, some of the mechanical parameters of comet 67P/Churyumov-Gerasimenko’s surface material are still not well constrained. They are needed to improve our understanding of cometary activity or for planning sample return procedures. Aims: We discuss the physical process dominating the formation of aeolian-like surface features in the form of moats and wind tail-like bedforms around obstacles and investigate the mechanical and geometrical parameters involved. Methods: By applying the discrete element method (DEM) in a low-gravity environment, we numerically simulated the dynamics of the surface layer particles and the particle stream involved in the formation of aeolian-like morphological features. The material is composed of polydisperse spherical particles that consist of a mixture of dust and water ice, with interparticle forces given by the Hertz contact model, cohesion, friction, and rolling friction. We determined a working set of parameters that enables simulations to be reasonably realistic and investigated morphological changes when modifying these parameters. Results: The aeolian-like surface features are reasonably well reproduced using model materials with a tensile strength on the order of 0.1–1 Pa. Stronger materials and obstacles with round shapes impede the formation of a moat and a wind tail. The integrated dust flux required for the formation of moats and wind tails is on the order of 100 kg^m−2, which, based on the timescale of morphological changes inferred from Rosetta images, translates to a near-surface particle density on the order of 10^−6–10^−4 kg m^−3. Conclusions: DEM modeling of the aeolian-like surface features reveals complex formation mechanisms that involve both deposition of ejected material and surface erosion. More numerical work and additional in situ measurements or sample return missions are needed to better investigate mechanical parameters of cometary surface material and to understand the mechanics of cometary activity

Discrete element modeling of boulder and cliff morphologies on comet 67P/Churyumov-Gerasimenko

Context. Even after the Rosetta mission, some of the mechanical parameters of comet 67P/Churyumov-Gerasimenko's surface material are not yet well constrained. These parameters are needed to improve our understanding of cometary activity or for planning sample return missions. Aims. We study some of the physical processes involved in the formation of selected surface features and investigate the mechanicaland geometrical parameters involved. Methods. Applying the discrete element method (DEM) in a low-gravity environment, we numerically simulated the surface layer particle dynamics involved in the formation of selected morphological features. The material considered is a mixture of polydisperse ice and dust spheres with inter-particle forces given by the Hertz contact model, translational friction, rolling friction, cohesion from unsintered contacts, and optionally due to bonds from ice sintering. We determined a working set of parameters that enables the simulations to be reasonably realistic and investigated morphological changes due to modifications thereof. Results. The selected morphological features are reasonably well reproduced using model materials with a tensile strength on the order of 1-10 Pa. Increasing the diameters of the spherical particles decreases the material strength, and increasing the friction leads to a more brittle but somewhat stronger material. High friction is required to make the material sufficiently brittle to match observations, which points to the presence of very rough, even angular particles. Reasonable seismic activity does not suffice to trigger the collapses of cliffs without material heterogeneities or structural defects. Conclusions. DEM modeling can be a powerful tool to investigate mechanical parameters of cometary surface material. However, many uncertainties arise from our limited understanding of particle shapes, spatial configurations, and size distributions, all on multiple length scales. Further numerical work, in situ measurements, and sample return missions are needed to better understand the mechanics of cometary material and cometary activity

Procalcitonin is not sufficiently reliable to be the sole marker of neonatal sepsis of nosocomial origin

BACKGROUND: It has recently been suggested that serum procalcitonin (PCT) is of value in the diagnosis of neonatal sepsis, with varying results. The aim of this prospective multicenter study was to assess the usefulness of PCT as a marker of neonatal sepsis of nosocomial origin. METHODS: One hundred infants aged between 4 and 28 days of life admitted to the Neonatology Services of 13 acute-care teaching hospitals in Spain over 1-year with clinical suspicion of neonatal sepsis of nosocomial origin were included in the study. Serum PCT concentrations were determined by a specific immunoluminometric assay. The reliability of PCT for the diagnosis of nosocomial neonatal sepsis at the time of suspicion of infection and at 12–24 h and 36–48 h after the onset of symptoms was calculated by receiver-operating characteristics (ROC) curves. The Youden's index (sensitivity + specificity - 1) was used for determination of optimal cutoff values of the diagnostic tests in the different postnatal periods. Sensitivity, specificity, and the likelihood ratio of a positive and negative result with the 95% confidence interval (CI) were calculated. RESULTS: The diagnosis of nosocomial sepsis was confirmed in 61 neonates. Serum PCT concentrations were significantly higher at initial suspicion and at 12–24 h and 36–48 h after the onset of symptoms in neonates with confirmed sepsis than in neonates with clinically suspected but not confirmed sepsis. Optimal PCT thresholds according to ROC curves were 0.59 ng/mL at the time of suspicion of sepsis (sensitivity 81.4%, specificity 80.6%); 1.34 ng/mL within 12–24 h of birth (sensitivity 73.7%, specificity 80.6%), and 0.69 ng/mL within 36–48 h of birth (sensitivity 86.5%, specificity 72.7%). CONCLUSION: Serum PCT concentrations showed a moderate diagnostic reliability for the detection of nosocomial neonatal sepsis from the time of suspicion of infection. PCT is not sufficiently reliable to be the sole marker of sepsis, but would be useful as part of a full sepsis evaluation

Genetic variability in CYP3A4 and CYP3A5 in primary liver, gastric and colorectal cancer patients

<p>Abstract</p> <p>Background</p> <p>Drug-metabolizing enzymes play a role in chemical carcinogenesis through enzymatic activation of procarcinogens to biologically reactive metabolites. The role of gene polymorphisms of several cytochrome P450 enzymes in digestive cancer risk has been extensively investigated. However, the drug-metabolizing enzymes with the broader substrate specificity, CYP3A4 and CYP3A5, have not been analyzed so far. This study aims to examine associations between common CYP3A4 and CYP3A5 polymorphisms and digestive cancer risk.</p> <p>Methods</p> <p>CYP3A4 and CYP3A5 genotypes were determined in 574 individuals including 178 patients with primary liver cancer, 82 patients with gastric cancer, 151 patients with colorectal cancer, and 163 healthy individuals.</p> <p>Results</p> <p>The variant allele frequencies for patients with liver cancer, gastric cancer, colorectal cancer and healthy controls, respectively, were: <it>CYP3A4*1B</it>, 4.8 % (95% C.I. 2.6–7.0), 3.7 % (0.8–6.6) 4.3% (2.0–6.6) and 4.3% (2.1–6.5); <it>CYP3A5*3</it>, 91.8 % (93.0–97.4), 95.7% (92.6–98.8), 91.7% (88.6–94.8) and 90.8% (87.7–93.9). The association between <it>CYP3A4*1B </it>and <it>CYP3A5*3 </it>variant alleles did not significantly differ among patients and controls. No differences in genotypes, allele frequencies, or association between variant alleles were observed with regard to gender, age at diagnosis, tumour site or stage.</p> <p>Conclusion</p> <p>Common polymorphisms on <it>CYP3A4 </it>and <it>CYP3A5 </it>genes do not modify the risk of developing digestive cancers in Western Europe.</p