Enhanced (1)G(4) emission in NaLaF4: Pr3+, Yb3+ and charge transfer in NaLaF4: Ce3+, Yb3+ studied by fourier transform luminescence spectroscopy

A high resolution luminescence study of NaLaF4: 1%Pr3+, 5%Yb3+ and NaLaF4: 1%Ce3+, 5%Yb3+ in the UV to NIR spectral range using a InGaAs detector and a fourier transform interferometer is reported. Although the Pr3+(P-3(0) -> (1)G(4), Yb3+(F-2(7/2) -> F-2(5/2)) energy transfer step takes place, significant Pr3+ (1)G(4) emission around 993, 1330 and 1850 nm is observed. No experimental proof for the second energy transfer step in the down-conversion process between Pr3+ and Yb3+ can be given. In the case of NaLaF4: Ce3+, Yb3+ it is concluded that the observed Yb3+ emission upon Ce3+ 5d excitation is the result of a charge transfer process instead of down-conversion. (C) 2010 Elsevier B.V. All rights reserved.

Application of Discrete Fourier Inter-Coefficient Difference for Assessing Genetic Sequence Similarity

Digital signal processing (DSP) techniques for biological sequence analysis continue to grow in popularity due to the inherent digital nature of these sequences. DSP methods have demonstrated early success for detection of coding regions in a gene. Recently, these methods are being used to establish DNA gene similarity. We present the inter-coefficient difference (ICD) transformation, a novel extension of the discrete Fourier transformation, which can be applied to any DNA sequence. The ICD method is a mathematical, alignment-free DNA comparison method that generates a genetic signature for any DNA sequence that is used to generate relative measures of similarity among DNA sequences. We demonstrate our method on a set of insulin genes obtained from an evolutionarily wide range of species, and on a set of avian influenza viral sequences, which represents a set of highly similar sequences. We compare phylogenetic trees generated using our technique against trees generated using traditional alignment techniques for similarity and demonstrate that the ICD method produces a highly accurate tree without requiring an alignment prior to establishing sequence similarity.

An Elaboration of the Psycho-Physiological Method and its Application on the Process of Socialization of Mentally Handicapped People

The socialisation of mentally handicapped people is a long-term process during which the disabled person learns new habits and abilities step by step through education and training. Anxiety and neuroses due to an inadequate social environment can place obstacles in the path of the disabled person's integration into society. A method of regulating the psycho-physiological condition of mentally handicapped people (MRPC) was developed in order to reduce anxiety and neuropsychological tension and to establish positive social attitudes. Both verbal and non-verbal means of manipulating the psycho-physiological condition were used and experimental and control groups were formed from among the clients of Israelian's institute. The experimental groups applied the new method for six months, leading to a significant shift in the response of the clients involved. Expressed anxiety and defensive responses to mental tasks were transformed into orienting responses after 30 psycho-regulative exercises. Cognitive functions such as attention and memory also improved significantly. EEG examinations of the actual process of psycho-regulation revealed a tendency towards a change of brain activity by increasing the fast pulse frequency values in the alpha zones. Israelian concludes that the application of the MRPC creates better functional conditions for the socialisation of mentally handicapped people.

Two-step postmortem angiography with a modified heart-lung machine: preliminary results

OBJECTIVE: The purpose of this study was to adapt and improve a minimally invasive two-step postmortem angiographic technique for use on human cadavers. Detailed mapping of the entire vascular system is almost impossible with conventional autopsy tools. The technique described should be valuable in the diagnosis of vascular abnormalities. MATERIALS AND METHODS: Postmortem perfusion with an oily liquid is established with a circulation machine. An oily contrast agent is introduced as a bolus injection, and radiographic imaging is performed. In this pilot study, the upper or lower extremities of four human cadavers were perfused. In two cases, the vascular system of a lower extremity was visualized with anterograde perfusion of the arteries. In the other two cases, in which the suspected cause of death was drug intoxication, the veins of an upper extremity were visualized with retrograde perfusion of the venous system. RESULTS: In each case, the vascular system was visualized up to the level of the small supplying and draining vessels. In three of the four cases, vascular abnormalities were found. In one instance, a venous injection mark engendered by the self-administration of drugs was rendered visible by exudation of the contrast agent. In the other two cases, occlusion of the arteries and veins was apparent. CONCLUSION: The method described is readily applicable to human cadavers. After establishment of postmortem perfusion with paraffin oil and injection of the oily contrast agent, the vascular system can be investigated in detail and vascular abnormalities rendered visible.

The Application of Laser-Ablation Split-Stream ICP Petrochronology to Metamorphic Studies

Discussion of a new, innovative method for dating rocks, called laser ablation split stream (LASS) petrochronology, which is an in situ method that couples geochronological and geochemical data of minerals that remain in the rock matrix. The talk focuses on the application of this technique with U-Th-Pb dating of the phosphate minerals monazite and xenotine in metamorphic rocks. Examples from the Ruby Range in southwestern Montana and metamorphic core complexes in the northern Idaho panhandle will be explored.

The High School Transition: A Step Ahead or a Downward Trend

This research was recorded to discourage the placement of 7th and 8th graders into the Anaconda High School, because it was thought that the earlier transition to the high school environment causes poor and illegal decisions to be made as well causing a decrease in the responsibility of students. The research was conducted using the survey research method, and the surveys that were dispersed to the 7th grade through sophomore classes took all possible ethical concerns into consideration. The data collected showed significant increases in the consumption of both alcohol and marijuana after students had made the transition into high school, as well as decreases in student’s levels of responsibility if a substance was being abused.

A Measurement System Experiment to Evaluate the Nosing-to-nosing Method for Measuring Dimensions of Steps

Non-uniformity of steps within a flight is a major risk factor for falls. Guidelines and requirements for uniformity of step risers and tread depths assume the measurement system provides precise dimensional values. The state-of-the-art measurement system is a relatively new method, known as the nosing-to-nosing method. It involves measuring the distance between the noses of adjacent steps and the angle formed with the horizontal. From these measurements, the effective riser height and tread depth are calculated. This study was undertaken for the purpose of evaluating the measurement system to determine how much of total measurement variability comes from the step variations versus that due to repeatability and reproducibility (R&R) associated with the measurers. Using an experimental design quality control professionals call a measurement system experiment, two measurers measured all steps in six randomly selected flights, and repeated the process on a subsequent day. After marking each step in a flight in three lateral places (left, center, and right), the measurers took their measurement. This process yielded 774 values of riser height and 672 values of tread depth. Results of applying the Gage R&R ANOVA procedure in Minitab software indicated that the R&R contribution to riser height variability was 1.42%; and to tread depth was 0.50%. All remaining variability was attributed to actual step-to-step differences. These results may be compared with guidelines used in the automobile industry for measurement systems that consider R&R less than 1% as an acceptable measurement system; and R&R between 1% and 9% as acceptable depending on the application, the cost of the measuring device, cost of repair, or other factors.

Split-mouth designs in orthodontics: an overview with applications to orthodontic clinical trials

SUMMARY Split-mouth designs first appeared in dental clinical trials in the late sixties. The main advantage of this study design is its efficiency in terms of sample size as the patients act as their own controls. Cited disadvantages relate to carry-across effects, contamination or spilling of the effects of one intervention to another, period effects if the interventions are delivered at different time periods, difficulty in finding similar comparison sites within patients and the requirement for more complex data analysis. Although some additional thought is required when utilizing a split-mouth design, the efficiency of this design is attractive, particularly in orthodontic clinical studies where carry-across, period effects and dissimilarity between intervention sites does not pose a problem. Selection of the appropriate research design, intervention protocol and statistical method accounting for both the reduced variability and potential clustering effects within patients should be considered for the trial results to be valid.

Marital split-up and widowhood in old age: Differential impact on psychological and social well-being

Marital split-up and spousal loss are among the most stressful critical life events. Numerous studies have documented their detrimental effects on well-being, yet the large individual differences in psychological adaptation are still not well understood. Whereas in old age bereavement is normative and can be anticipated, divorce is an “off-time” transition for this age group. In contrast to bereavement which has been amply studied, research on later life divorce is still missing despite the increasing relevance of the topic due to the significant increase of divorces in older age. Based on a modified and extended view of Amato’s divorce-stress-adjustment model (2000), the aim of this contribution is to explore the differential impact of marital split-up and widowhood in older age on psychological (life satisfaction) and social well-being (social loneliness), and the adaptation to these critical life events. Our analyses are based on data gathered in a questionnaire study, which is part of the Swiss National Centre of Competence in Research LIVES. In a first step we compared three groups of individuals aged 60 to 75 years: a sample of 251 persons with a marital split-up (127 women; 123 men), a sample of 270 widowed persons (170 women; 100 men), and a group of 221 continuously married people (110 women; 111 men), which served as control group. In a second step, we investigated the role of socio-demographic variables, intrapersonal and interpersonal resources and variables of the context of loss as predictors for the psychological adaptation to a marital break-up and loss in old age. First results by ANCOVA indicate significant differences with regard to life satisfaction among the three groups, with divorced persons with the lowest scores, followed by the bereaved ones, and the married controls with the highest. Regarding social loneliness, divorced individuals report higher social loneliness than the bereaved group and the married controls (no significant difference between widowed and the married). In both loss groups, financial and intrapersonal resources, as well as the emotional valence of the loss are the most important predictors for the psychological and social adaptation. However, happiness in the past relationship is an important resource regarding the indicators for adaptation for the widowers, but not for individuals with a marital dissolution.

An adaptive Newton-method based on a dynamical systems approach

The traditional Newton method for solving nonlinear operator equations in Banach spaces is discussed within the context of the continuous Newton method. This setting makes it possible to interpret the Newton method as a discrete dynamical system and thereby to cast it in the framework of an adaptive step size control procedure. In so doing, our goal is to reduce the chaotic behavior of the original method without losing its quadratic convergence property close to the roots. The performance of the modified scheme is illustrated with various examples from algebraic and differential equations.

Automatic estimation of noise parameters in Fourier-domain optical coherence tomography cross sectional images using statistical information

We present an application and sample independent method for the automatic discrimination of noise and signal in optical coherence tomography Bscans. The proposed algorithm models the observed noise probabilistically and allows for a dynamic determination of image noise parameters and the choice of appropriate image rendering parameters. This overcomes the observer variability and the need for a priori information about the content of sample images, both of which are challenging to estimate systematically with current systems. As such, our approach has the advantage of automatically determining crucial parameters for evaluating rendered image quality in a systematic and task independent way. We tested our algorithm on data from four different biological and nonbiological samples (index finger, lemon slices, sticky tape, and detector cards) acquired with three different experimental spectral domain optical coherence tomography (OCT) measurement systems including a swept source OCT. The results are compared to parameters determined manually by four experienced OCT users. Overall, our algorithm works reliably regardless of which system and sample are used and estimates noise parameters in all cases within the confidence interval of those found by observers.

Fusion of fundus images and MRI data of the human eye

Purpose Ophthalmologists are confronted with a set of different image modalities to diagnose eye tumors e.g., fundus photography, CT and MRI. However, these images are often complementary and represent pathologies differently. Some aspects of tumors can only be seen in a particular modality. A fusion of modalities would improve the contextual information for diagnosis. The presented work attempts to register color fundus photography with MRI volumes. This would complement the low resolution 3D information in the MRI with high resolution 2D fundus images. Methods MRI volumes were acquired from 12 infants under the age of 5 with unilateral retinoblastoma. The contrast-enhanced T1-FLAIR sequence was performed with an isotropic resolution of less than 0.5mm. Fundus images were acquired with a RetCam camera. For healthy eyes, two landmarks were used: the optic disk and the fovea. The eyes were detected and extracted from the MRI volume using a 3D adaption of the Fast Radial Symmetry Transform (FRST). The cropped volume was automatically segmented using the Split Bregman algorithm. The optic nerve was enhanced by a Frangi vessel filter. By intersection the nerve with the retina the optic disk was found. The fovea position was estimated by constraining the position with the angle between the optic and the visual axis as well as the distance from the optic disk. The optical axis was detected automatically by fitting a parable on to the lens surface. On the fundus, the optic disk and the fovea were detected by using the method of Budai et al. Finally, the image was projected on to the segmented surface using the lens position as the camera center. In tumor affected eyes, the manually segmented tumors were used instead of the optic disk and macula for the registration. Results In all of the 12 MRI volumes that were tested the 24 eyes were found correctly, including healthy and pathological cases. In healthy eyes the optic nerve head was found in all of the tested eyes with an error of 1.08 +/- 0.37mm. A successful registration can be seen in figure 1. Conclusions The presented method is a step toward automatic fusion of modalities in ophthalmology. The combination enhances the MRI volume with higher resolution from the color fundus on the retina. Tumor treatment planning is improved by avoiding critical structures and disease progression monitoring is made easier.

Privacy Preserving Probabilistic Record Linkage (P3RL): a novel method for linking existing health-related data and maintaining participant confidentiality.

BACKGROUND Record linkage of existing individual health care data is an efficient way to answer important epidemiological research questions. Reuse of individual health-related data faces several problems: Either a unique personal identifier, like social security number, is not available or non-unique person identifiable information, like names, are privacy protected and cannot be accessed. A solution to protect privacy in probabilistic record linkages is to encrypt these sensitive information. Unfortunately, encrypted hash codes of two names differ completely if the plain names differ only by a single character. Therefore, standard encryption methods cannot be applied. To overcome these challenges, we developed the Privacy Preserving Probabilistic Record Linkage (P3RL) method. METHODS In this Privacy Preserving Probabilistic Record Linkage method we apply a three-party protocol, with two sites collecting individual data and an independent trusted linkage center as the third partner. Our method consists of three main steps: pre-processing, encryption and probabilistic record linkage. Data pre-processing and encryption are done at the sites by local personnel. To guarantee similar quality and format of variables and identical encryption procedure at each site, the linkage center generates semi-automated pre-processing and encryption templates. To retrieve information (i.e. data structure) for the creation of templates without ever accessing plain person identifiable information, we introduced a novel method of data masking. Sensitive string variables are encrypted using Bloom filters, which enables calculation of similarity coefficients. For date variables, we developed special encryption procedures to handle the most common date errors. The linkage center performs probabilistic record linkage with encrypted person identifiable information and plain non-sensitive variables. RESULTS In this paper we describe step by step how to link existing health-related data using encryption methods to preserve privacy of persons in the study. CONCLUSION Privacy Preserving Probabilistic Record linkage expands record linkage facilities in settings where a unique identifier is unavailable and/or regulations restrict access to the non-unique person identifiable information needed to link existing health-related data sets. Automated pre-processing and encryption fully protect sensitive information ensuring participant confidentiality. This method is suitable not just for epidemiological research but also for any setting with similar challenges.

An automated method for mapping physical soil and water conservation structures on cultivated land using GIS and remote sensing techniques

An efficient and reliable automated model that can map physical Soil and Water Conservation (SWC) structures on cultivated land was developed using very high spatial resolution imagery obtained from Google Earth and ArcGIS, ERDAS IMAGINE, and SDC Morphology Toolbox for MATLAB and statistical techniques. The model was developed using the following procedures: (1) a high-pass spatial filter algorithm was applied to detect linear features, (2) morphological processing was used to remove unwanted linear features, (3) the raster format was vectorized, (4) the vectorized linear features were split per hectare (ha) and each line was then classified according to its compass direction, and (5) the sum of all vector lengths per class of direction per ha was calculated. Finally, the direction class with the greatest length was selected from each ha to predict the physical SWC structures. The model was calibrated and validated on the Ethiopian Highlands. The model correctly mapped 80% of the existing structures. The developed model was then tested at different sites with different topography. The results show that the developed model is feasible for automated mapping of physical SWC structures. Therefore, the model is useful for predicting and mapping physical SWC structures areas across diverse areas.

Combinations of dexmedetomidine and alfaxalone with butorphanol in cats: application of an innovative stepwise optimisation method to identify optimal clinical doses for intramuscular anaesthesia

OBJECTIVES The aim of this study was to optimise dexmedetomidine and alfaxalone dosing, for intramuscular administration with butorphanol, to perform minor surgeries in cats. METHODS Initially, cats were assigned to one of five groups, each composed of six animals and receiving, in addition to 0.3 mg/kg butorphanol intramuscularly, one of the following: (A) 0.005 mg/kg dexmedetomidine, 2 mg/kg alfaxalone; (B) 0.008 mg/kg dexmedetomidine, 1.5 mg/kg alfaxalone; (C) 0.012 mg/kg dexmedetomidine, 1 mg/kg alfaxalone; (D) 0.005 mg/kg dexmedetomidine, 1 mg/kg alfaxalone; and (E) 0.012 mg/kg dexmedetomidine, 2 mg/kg alfaxalone. Thereafter, a modified 'direct search' method, conducted in a stepwise manner, was used to optimise drug dosing. The quality of anaesthesia was evaluated on the basis of composite scores (one for anaesthesia and one for recovery), visual analogue scales and the propofol requirement to suppress spontaneous movements. The medians or means of these variables were used to rank the treatments; 'unsatisfactory' and 'promising' combinations were identified to calculate, through the equation first described by Berenbaum in 1990, new dexmedetomidine and alfaxalone doses to be tested in the next step. At each step, five combinations (one new plus the best previous four) were tested. RESULTS None of the tested combinations resulted in adverse effects. Four steps and 120 animals were necessary to identify the optimal drug combination (0.014 mg/kg dexmedetomidine, 2.5 mg/kg alfaxalone and 0.3 mg/kg butorphanol). CONCLUSIONS AND RELEVANCE The investigated drug mixture, at the doses found with the optimisation method, is suitable for cats undergoing minor clinical procedures.