Comparison of The Kois Dento-Facial Analyzer System with an Earbow for Mounting a Maxillary Cast

Statement of problem: The Kois Dento-Facial Analyzer System (KDFA) is used by clinicians to mount maxillary casts and evaluate and treat patients. Limited information is available for understanding whether the KDFA should be considered as an alternative to an earbow. Purpose: The purpose of this study was to evaluate maxillary casts mounted using the KDFA with casts mounted using Panadent\u27s Pana-Mount Facebow (PMF). Both articulation methods were compared against a lateral cephalometric radiograph. Material and methods: Fifteen dried human skulls were used. Lateral cephalometric radiographs and 2 maxillary impressions were made of each skull. One cast from each skull was mounted on an articulator by means of the KDFA and the other by using the PMF. A standardized photograph of each articulation was made, and the distance from the articular center to the incisal edge position and the occlusal plane angle were measured. The distance from condylar center to the incisal edge and the occlusal plane angle were measured from cephalometric radiographs. Finally, the 3-dimensional position of each articulation was determined with a Panadent CPI-III. A randomized complete block design analysis of variance (RCBD) and post hoc tests (Tukey-Kramer HSD) (α=.05) were used to evaluate the occlusal plane angle and axis-central incisor distance. A paired 2-sample t test for means (α=.05) was used to compare the X, Y, and Z distance at the right and left condyle. Results: The KDFA and PMF mounted the maxillary cast in a position that was not statistically different from the skull when comparing the occlusal plane angle (P=.165). Both the KDFA and the PMF located the maxillary central incisor edge position in a significantly different position compared with the skull (P=.001) but were not significantly different from each other. The 3-dimensional location of the maxillary casts varied at the condyles by approximately 9 to 10.3 mm. Conclusion: The KDFA mounted the maxillary cast in a position that was not statistically different from the PMF when comparing the incisal edge position and the occlusal plane angle. Both the KDFA and the PMF located the maxillary incisal edge position in a significantly different position compared with the anatomic position on dried human skulls

Switching from Electron to Hole Transport in Solution-Processed Organic Blend Field-Effect Transistors

Organic electronics became an attractive alternative for practical applications in complementary logic circuits due to the unique features of organic semiconductors such as solution processability and ease of large-area manufacturing. Bulk heterojunctions (BHJ), consisting of a blend of two organic semiconductors of different electronic affinities, allow fabrication of a broad range of devices such as light-emitting transistors, light-emitting diodes, photovoltaics, photodetectors, ambipolar transistors and sensors. In this work, the charge carrier transport of BHJ films in field-effect transistors is switched from electron to hole domination upon processing and post-treatment. Low molecular weight n-type N,N′-bis(n-octyl)-(1,7&1,6)-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDI8-CN2) was blended with p-type poly[2,5-bis(3-tetradecylthiophene-2-yl)thieno[3,2-b]thiophene] (PBTTT-C14) and deposited by spin-coating to form BHJ films. Systematic investigation of the role of rotation speed, solution temperature, and thermal annealing on thin film morphology was performed using atomic force microscopy, scanning electron microscopy, and grazing incidence wide-angle X-ray scattering. It has been determined that upon thermal annealing the BHJ morphology is modified from small interconnected PDI8-CN2 crystals uniformly distributed in the polymer fraction to large planar PDI8-CN2 crystal domains on top of the blend film, leading to the switch from electron to hole transport in field-effect transistors

Self-Aligned Bilayers for Flexible Free-Standing Organic Field-Effect Transistors

[Image: see text] Free-standing and flexible field-effect transistors based on 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene)/polystyrene bilayers are obtained by well-controlled phase separation of both components. The phase separation is induced by solvent vapor annealing of initially amorphous blend films, leading to crystallization of TIPS-pentacene as the top layer. The crystallinity and blend morphology strongly depend on the molecular weight of polystyrene, and under optimized conditions, distinct phase separation with a well-defined and trap-free interface between both fractions is achieved. Due to the distinct bilayer morphology, the resulting flexible field-effect transistors reveal similar charge carrier mobilities as rigid devices and additionally pronounced environmental and bias stress stabilities. The performance of the flexible transistors remains stable up to a strain of 1.8%, while above this deformation, a close relation between current and strain is observed that is required for applications in strain sensors

Raspodjela lindana u vodi, sedimentu i ribama iz rijeke Warri (Delta Nigera, Nigerija)

This paper is the first attempt to quantify the levels and the distribution pattern of lindane in the surface water, sediment and fish (Chrysichthys furcatus and Tilapia zilli). The samples were collected from three stations (Ovwian, Ekakpamre, and Ovu) of the Warri River in the western Niger Delta of Nigeria in 2006: during the dry (January-April) and wet seasons (May-August). The analysis included a total of 96 samples made up of 24 samples each for water, sediment, and fish. The pesticide levels were analysed using high performance liquid chromatography to elucidate its distribution in various environmental compartments. Residue levels in the matrices ranged from below the detection limit (BDL) to 1.37µg L-1 in water, BDL to 12.66 µg g-1 dry weight (dw) in sediment, BDL to 16.67 µg g-1dw in Chrysichthys furcatus, and BDL to 0.15 µg g-1dw in Tilapia zilli .The observed values were above the ecological benchmarks (0.01 µg L-1) recommended by the Nigerian Environmental Protection Agency and European Union. They were also relatively higher than in previous studies on the Nigerian environment, which calls for regular monitoring of the Niger Delta water bodies.Istražene su pojava i raspodjela lindana u površinskoj vodi, sedimentu i dvije vrste riba Chrysichthys furcatus i Tilapia zilli iz rijeke Warri u zapadnom dijelu delte Nigera (Nigerija). Uzorci su skupljeni 2006. godine na tri postaje (Ovwian, Ekakpamre i Ovu) tijekom sušne (siječanj - travanj) i vlažne sezone (svibanj - kolovoz). Analizirano je ukupno 96 uzoraka: po 24 uzorka vode, sedimenta i riba. Razine pesticida odre|ene su primjenom tekućinske kromatografije visoke djelotvornosti (HPLC) te je utvr|ivana njihova raspodjela u različitim dijelovima okoliša. Koncentracije rezidua u uzorcima vode bile su u rasponu: ispod granice detekcije (BDL) do 1,37 µg L-1, u sedimentu: BDL do 12,66 µg g-1 suhe tvari, u ribama Chrysichthys furcatus: BDL do 16,67 µg g-1 suhe tvari te Tilapia zilli: BDL do 0,15 µg g-1 suhe tvari. Određene vrijednosti bile su ispod graničnih vrijednosti (0,01 µg L-1) propisanih od Nigerijske uprave za zaštitu okoliša i Europske unije. Kako su dobivene vrijednosti bile relativno više u odnosu na podatke iz ranijih istraživanja okoliša u Nigeriji, istaknuta je potreba trajnog monitoringa vodotoka u delti Nigera

Self-organization of developing embryo using scale-invariant approach

<p>Abstract</p> <p>Background</p> <p>Self-organization is a fundamental feature of living organisms at all hierarchical levels from molecule to organ. It has also been documented in developing embryos.</p> <p>Methods</p> <p>In this study, a scale-invariant power law (SIPL) method has been used to study self-organization in developing embryos. The SIPL coefficient was calculated using a centro-axial skew symmetrical matrix (CSSM) generated by entering the components of the Cartesian coordinates; for each component, one CSSM was generated. A basic square matrix (BSM) was constructed and the determinant was calculated in order to estimate the SIPL coefficient. This was applied to developing <it>C. elegans </it>during early stages of embryogenesis. The power law property of the method was evaluated using the straight line and Koch curve and the results were consistent with fractal dimensions (fd). Diffusion-limited aggregation (DLA) was used to validate the SIPL method.</p> <p>Results and conclusion</p> <p>The fractal dimensions of both the straight line and Koch curve showed consistency with the SIPL coefficients, which indicated the power law behavior of the SIPL method. The results showed that the ABp sublineage had a higher SIPL coefficient than EMS, indicating that ABp is more organized than EMS. The fd determined using DLA was higher in ABp than in EMS and its value was consistent with type 1 cluster formation, while that in EMS was consistent with type 2.</p

Inter-population variations in concentrations, determinants of and correlations between 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE): a cross-sectional study of 3161 men and women from Inuit and European populations

BACKGROUND: The study is part of a collaborative project (Inuendo), aiming to assess the impact of dietary persistent organochlorine pollutants (POPs) on human fertility. The aims with the present study are to analyze inter-population variations in serum concentrations of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE), to assess inter-population variations in biomarker correlations, and to evaluate the relative impact of different determinants for the inter-individual variations in POP-biomarkers. METHOD: In study populations of 3161 adults, comprising Greenlandic Inuits, Swedish fishermen and their wives, and inhabitants from Warsaw, Poland and Kharkiv, Ukraine, serum concentrations of CB-153 and p,p'-DDE, were analysed by gas chromatography-mass spectrometry. RESULTS: The median serum concentrations of CB-153 were for male and female Inuits 200 and 110, for Swedish fishermen 190 and their wives 84, for Kharkiv men and women 44 and 27, and for Warsaw men and women 17 and 11 ng/g lipids, respectively. The median serum concentrations of p,p'-DDE were for Kharkiv men and women 930 and 650, for male and female Inuits 560 and 300, for Warsaw men and women 530 and 380, and for Swedish fishermen 240 and their wives 140 ng/g lipids, respectively. The correlation coefficients between CB-153 and p,p'-DDE varied between 0.19 and 0.92, with the highest correlation among Inuits and the lowest among men from Warsaw. Men had averagely higher serum concentrations of CB-153 and p,p'-DDE, and there were positive associations between age and the POP-biomarkers, whereas the associations with BMI and smoking were inconsistent. Dietary seafood was of importance only in the Inuit and Swedish populations. CONCLUSION: CB-153 concentrations were much higher in Inuits and Swedish fishermen's populations than in the populations from Eastern Europe, whereas the pattern was different for p,p'-DDE showing highest concentrations in the Kharkiv population. The correlations between the POP-biomarkers varied considerably between the populations, underlining that exposure sources differ and that the choice of representative biomarkers of overall POP exposure has to be based on an analysis of the specific exposure situation for each population. Age and gender were consistent determinants of serum POPs; seafood was of importance only in the Inuit and Swedish populations

Applicability of non-invasively collected matrices for human biomonitoring

With its inclusion under Action 3 in the Environment and Health Action Plan 2004–2010 of the European Commission, human biomonitoring is currently receiving an increasing amount of attention from the scientific community as a tool to better quantify human exposure to, and health effects of, environmental stressors. Despite the policy support, however, there are still several issues that restrict the routine application of human biomonitoring data in environmental health impact assessment. One of the main issues is the obvious need to routinely collect human samples for large-scale surveys. Particularly the collection of invasive samples from susceptible populations may suffer from ethical and practical limitations. Children, pregnant women, elderly, or chronically-ill people are among those that would benefit the most from non-invasive, repeated or routine sampling. Therefore, the use of non-invasively collected matrices for human biomonitoring should be promoted as an ethically appropriate, cost-efficient and toxicologically relevant alternative for many biomarkers that are currently determined in invasively collected matrices. This review illustrates that several non-invasively collected matrices are widely used that can be an valuable addition to, or alternative for, invasively collected matrices such as peripheral blood sampling. Moreover, a well-informed choice of matrix can provide an added value for human biomonitoring, as different non-invasively collected matrices can offer opportunities to study additional aspects of exposure to and effects from environmental contaminants, such as repeated sampling, historical overview of exposure, mother-child transfer of substances, or monitoring of substances with short biological half-lives