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PubMed1987

Changing time perspective and mental health among Southeast Asian refugees.

Little is known about the psychological mechanisms people employ in adapting to extreme circumstances such as becoming refugees. Case studies of refugees making up part of a sample of 1348 persons relocated from Southeast Asia to Vancouver, British Columbia, suggest that altering one's perception of time may be an adaptive strategy. During periods of acute stress, refugees seem to focus on the present to the relative exclusion of past and future. The reemergence of past and future into consciousness brings about a risk for developing depression. Epidemiological data corroborate inferences from case material, demonstrating that refugees are more present-oriented than the indigenous population. A "Nostalgic" time orientation, preoccupation with the past, is associated with elevated depression scores. Contrasts are drawn between nostalgia, a maladaptive pattern, and memory, which is an inevitable part of the process of personality integration.

Acculturation↗
PubMed1994

Hertel exophthalmometry without orbital rim contact.

BACKGROUND: The Hertel exophthalmometer is the most widely used instrument for the measurement of globe malposition, but an absent or damaged lateral orbital rim will preclude its application. To circumvent this shortcoming, the authors have developed a fixation adapter that attaches to a standard Hertel instrument and transfers fixation to the forehead and nasion from the lateral orbit. METHODS: The adapter design is presented and discussed, along with illustrative clinical cases. A study of 30 healthy patients was performed to assess the validity of the adapter with respect to the Hertel standard. The agreement was then evaluated by comparing the Hertel adapter measurements from each patient with that of the adapter. A Wilcoxon statistic was performed to assess differences in the paired values from each patient for both techniques. RESULTS: Analysis on a sample (n = 30) of a healthy adult population does not show a statistical difference between the Hertel adapter and the adapter data (P > 0.05). In addition, more than 90% of the differences fall within +/- 1 mm (standard deviation = 1.02 mm) of the means for both eyes, which is within the accepted variance for the Hertel instrument. CONCLUSION: The new fixation adapter promises to become useful in assessing trauma and surgical cases where the lateral orbital rim has been violated and will expand the application of Hertel exophthalmometry to these situations.

Anthropometry↗
PubMed2001

Computational adaptive optics for live three-dimensional biological imaging.

Light microscopy of thick biological samples, such as tissues, is often limited by aberrations caused by refractive index variations within the sample itself. This problem is particularly severe for live imaging, a field of great current excitement due to the development of inherently fluorescent proteins. We describe a method of removing such aberrations computationally by mapping the refractive index of the sample using differential interference contrast microscopy, modeling the aberrations by ray tracing through this index map, and using space-variant deconvolution to remove aberrations. This approach will open possibilities to study weakly labeled molecules in difficult-to-image live specimens.

Animals↗
PubMed1988

[Adaptation of adolescents to the death or divorce of parents.].

Research conducted on a sample of 5,539 francophone adolescents of the island of Montréal (from first year of High School to last year of Cégep) shows 446 children with divorced parents (9.82 %) and 330 orphans (7.27%). Simple and controlled comparisons of these two groups with adolescents living with both parents reveal a regular pattern where children of divorced families perceive themselves at a disadvantage, followed by orphans in the middle. The authors also analyse how the length of a divorce, the age at which parents divorced and the sex of the guardian parent influence the children. The authors then discuss the fact there are more girls born from divorced families.

English Abstract↗
PubMed2000

Comparison of microbial populations in model and natural rumens using 16S ribosomal RNA-targeted probes.

A model rumen system, dual-flow continuous culture fermenters, was evaluated by two comparative criteria in two experiments using ribosomal (r)RNA-targeted DNA probes to compare key microbial groups in samples. The initial experiment measured temporal changes in population structure during adaptation of ruminal microbial populations in fermenters over 240 h. The fermenter inoculum contained 34.9% Bacteria, 60.1% Eukarya and 6.8% Archaea measured as a fraction of total small subunit (SSU) rRNA quantified using a universal probe. The cellulolytic bacterial genus Fibrobacter comprised 9.5% of total SSU rRNA in the inoculum. After 240 h of fermenter operation, the average abundance was 80.9% Bacteria, 6.1% Eukarya, 5.1% Archaea and Fibrobacter genus accounted for 6.6% of the total SSU rRNA. Divergence between ruminal and fermenter population structure was evaluated in the second experiment and samples were classified as ruminal, inoculum or fermenter (96, 120, 144 and 168 h of fermenter operation). Fermenter samples had higher relative abundances of Bacteria (84.5%) and Archaea (2.1%) and lower relative abundances of Eukarya (1.8%) than ruminal samples (average 48.0% Bacteria, 1.3% Archaea and 61.5% Eukarya). The relative abundance of Fibrobacter was similar in all samples, averaging 2.5%. The ruminal and fermenter samples had similar proportions of F. succinogenes and F. succinogenes subgroup 3 (as a percentage of Fibrobacter SSU rRNA). Fibrobacter succinogenes subgroup 1 and F. intestinalis proportions of Fibrobacter were lower in fermenter samples (8.2% and 0.7% respectively) than in ruminal samples (28.4% and 2.2% respectively). Fermenters were able to maintain a core prokaryotic community structure similar to the native microbial community in the rumen. Although protozoa populations were lost, maintenance of Fibrobacter and archaeal populations indicated that the model system supported a functional community structure similar to the rumen. This model rumen system may serve as a suitable tool for studying aspects of ruminal microbial ecology and may resolve some of the relationships between microbial community structure and function by providing control of experimental conditions.

Animals↗
PubMed2004

Effects of birthplace and individual genetic admixture on lung volume and exercise phenotypes of Peruvian Quechua.

Forced vital capacity (FVC) and maximal exercise response were measured in two populations of Peruvian males (age, 18-35 years) at 4,338 m who differed by the environment in which they were born and raised, i.e., high altitude (Cerro de Pasco, Peru, BHA, n = 39) and sea level (Lima, Peru, BSL, n = 32). BSL subjects were transported from sea level to 4,338 m, and were evaluated within 24 hr of exposure to hypobaric hypoxia. Individual admixture level (ADMIX, % Spanish ancestry) was estimated for each subject, using 22 ancestry-informative genetic markers and also by skin reflectance measurement (MEL). Birthplace accounted for the approximately 10% larger FVC (P < 0.001), approximately 15% higher maximal oxygen consumption (VO(2)max, ml.min(-1).kg(-1)) (P < 0.001), and approximately 5% higher arterial oxygen saturation during exercise (SpO(2)) (P < 0.001) of BHA subjects. ADMIX was low in both study groups, averaging 9.5 +/- 2.6% and 2.1 +/- 0.3% in BSL and BHA subjects, respectively. Mean underarm MEL was significantly higher in the BSL group (P < 0.001), despite higher ADMIX. ADMIX was not associated with any study phenotype, but study power was not sufficient to evaluate hypotheses of genetic adaptation via the ADMIX variable. MEL and FVC were positively correlated in the BHA (P = 0.035) but not BSL (P = 0.335) subjects. However, MEL and ADMIX were not correlated across the entire study sample (P = 0.282). In summary, results from this study emphasize the importance of developmental adaptation to high altitude. While the MEL-FVC correlation may reflect genetic adaptation to high altitude, study results suggest that alternate (environmental) explanations be considered.

Acclimatization↗
PubMed1997

Cognitive impairment in geriatric chronic schizophrenic patients: a cross-national study in New York and London.

Severe cognitive impairment has been reported in large numbers of geriatric chronic schizophrenic patients in the US, with this impairment also being related to severe negative symptoms and adaptive deficits. It is not clear if this impairment is related to the particular environment of the American state hospitals and would not generalize to other countries. In this study, a sample composed of geriatric (age > 70) chronic schizophrenic patients in London, who were assessed by the Team for Assessment of Psychiatric Services (TAPS) (N = 137), and a group of geriatric chronic schizophrenic patients in a New York psychiatric center (N = 86) were compared for the severity of cognitive impairment and on measures of adaptive functioning. Patients received essentially identical Mini-Mental State Examination (MMSE) scores, but differed on 3/4 measures of adaptive functioning. The correlations among all four aspects of adaptive deficit and MMSE scores were very similar in the two samples, suggesting that cognitive deficits and their relationship with adaptive impairments are relatively invariant across different psychiatric systems of care, while adaptive functioning deficits are more variable and possibly more influenced by environmental factors. These data add to previous results suggesting that cognitive impairment is a common feature in poor outcome geriatric patients with schizophrenia.

Aged↗
PubMedDate not supplied

[Nutritional planning of menus of public schools of the community of Madrid].

Some nutritional unbalances have been observed in menus served at dining rooms of schools from the Community of Madrid (CM): small portions, inter-day variations up to 50% of energy intake, unbalances in caloric and lipidic profiles, little variety, lack of parental information, etc. The Education Council of the CM considered necessary to plan and regulate the basic conditions that menus of these dinning rooms should meet. The Spanish Nutrition Foundation (FEN) and the Nutrition Department of the Complutense University of Madrid (UCM) were put in charge of elaborating the bases to develop the Regulation (BOCM 24-05-01, 10-09-02). Collective catering companies were called for a tender to provide menus adapted to such Regulation. This work describes the adaptation of programmed dietary schemes of officially approved companies and mainly the impact on energy and nutritional content of menus and their adaptation to the recommended caloric and lipidic profiles. So far, a random sample of 171 schools with dining rooms (more than 37,000 schoolboys) has been visited by nutritionists, with no previous announcement, to control served menus. For this, at each centre a duplicate of the portion served that day was gathered. The energy and nutrient content was determined and the fatty acid composition was analysed. The adaptation to the Regulation by catering companies has substantially improved the menus as compared to previous times: more presence of vegetables, better quality of fat and less amount of fat and proteins at the expense of carbohydrates.

Child↗
PubMed2006

Models for estimating digesta passage kinetics in the gastrointestinal tract of the horse.

Fecal samples were collected to evaluate mathematical models to describe the kinetics of digesta passage in the segments of the equine gastrointestinal tract and to compare the passage kinetics of hay and oats. Four Norwegian Cold-blooded trotters (cecally cannulated, approximately 500 kg of BW) were fed Cr-mordanted hay and Yb-marked oats with their morning meal. The meal consisted of 2 kg of hay and 1 kg of oats processed as ground, pelleted, extruded, or micronized. Each horse was fed each type of oats on different days of collection, after a 5-d adaptation period, in a 4 x 4 Latin square design. Fecal samples were collected 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 48, and 52 h after administration of the marker dose. The samples were analyzed for Cr and Yb, and values were plotted using 1- and 2-compartment nonlinear passage models and an algebraic model. The 1-compartment G4 model and the 2-compartment G4G1 model showed an equally good fit to the observed excretion curves, based on low mean square error and SE. The excretion curves for hay (Cr) and oats (Yb) showed a striking similarity, and there seemed to be no difference in retention time between hay and oats in the horse. The mixing compartments in the horse are believed to be the cecum or both the cecum and the right ventral and dorsal segments of the colon, but further research in this area is needed to make a final conclusion.

Animal Feed↗
PubMed2005

Two mathematical models for the correction of carbohydrate and protein interference in the determination of uronic acids by the m-hydroxydiphenyl method.

The most common method in the routine determination of uronic acids, the m-hydroxydiphenyl reaction, recently adapted to rapid microplate analysis, has as a main inconvenience, in any one of their modalities, interferences due to the frequent presence of proteins and neutral carbohydrates in the samples. Corresponding corrections in the literature are unsatisfactory when applied to complex matrices, and further adaptation to the microplate analysis is not free from additional problems. With particular reference to hyaluronic acid, the interactions between the principal reactants and the interfering materials are studied kinetically under realistic conditions, and simple mathematical models are proposed which satisfactorily describe the experimental results and allow adequate corrections to be made.

Animals↗
PubMed1991

Emotional distress and its socio-political correlates in Salvadoran refugees: analysis of a clinical sample.

The emotional distress responses of refugees cannot be adequately understood using the traditional notions of stress and adaptation. In these populations it is necessary to consider the relations between emotional distress and socio-political context, particularly the processes of terror and intimidation and the conditions of migratory illegality and social marginality. This study analyses the patterns of emotional distress in a clinical sample of 71 Salvadoran refugees in an urban center of the United States. Case histories are presented and patterns of trauma, distress and associated life problems analyzed. It is argued that distress patterns reflect the particular socio-political conditions of women and men and represent the embodiment of the conflicts that refugees face. The concept of illness is used to link distress patterns and socio-political context and to avoid the reductionism of psychiatric categories.

Adult↗
PubMed2003

Random priming PCR strategy to amplify and clone trace amounts of DNA.

Here we report a new methodology to study trace amounts of DNA of unknown sequence using a two-step PCR strategy to amplify and clone target DNA. The first PCR is carried out with a partial random primer comprised of a specific 21-nucleotide 5' sequence, a random heptamer, and a 3' TGGC clamp. The second PCR is carried out with a single 19-nucleotide primer that matches the specific 5' sequence of the partial random primer. Using human and Mycoplasma genitalium DNA as examples, we demonstrated the efficiency of this approach by effectively cloning target DNA fragments from 1 pg DNA sample. The cloning sensitivity could reach 100 fg target DNA templates. Compared to the strategy of first adding adapter sequences to facilitate the PCR amplification of unknown sequences, this approach has the advantage of allowing for the amplification of DNA samples in both natural and denatured forms, which provides greater flexibility in sample preparation. This is an efficient strategy to retrieve sequences from trace DNA samples from various sources.

Cloning, Molecular↗
PubMed1996

EU experimental study on wild boar trichinellosis.

From January 1994 onwards the Council Directive 92/45 EEC concerning the examination of wild game meat for trichinellosis is valid. Laboratory methods required are identical to those used for the examination of pork. In an international experiment the suitability of these methods to control wild boar meat was tested. Required meat parts of experimentally with T. spiralis infected wild boars were shipped to seven laboratories in Europe under code. It was concluded that trichinoscopy and pool sample digestion methods meant for pork examination could equally well be used for control of wild boar meat. The so called Trichomatic method required a few adaptations. Moreover it was demonstrated that extra washing procedures were required to prevent cross contamination between samples with Trichomatic equipment.

Animals↗
PubMed1994

Improved Method for Recovery of mRNA from Aquatic Samples and Its Application to Detection of mer Expression.

Previously described methods for extraction of mRNA from environmental samples may preclude detecting transcripts from genes that were present in low abundance in aquatic bacterial communities. By combining a boiling sodium dodecyl sulfate-diethylpyrocarbonate lysis step with acid-guanidinium extraction, we improved recovery of target mRNA from both pure cultures and environmental samples. The most significant advantage of the new protocol is that it is easily adapted to yield high recovery of mRNA from 142-mm-diameter flat filters and high-capacity cartridge filters. The lysis and extraction procedures are more rapid than previously described methods, and many samples can be handled at once. RNA extracts have been shown to be free of contaminating DNA. The lysis procedure does not damage target mRNA sequences, and mRNA can be detected from fewer than 10 bacterial cells. We used the new method to examine transcripts of genes responsible for detoxification of mercurial compounds. Induction of merA (specifying mercuric reductase) transcripts in stationary-phase Pseudomonas aeruginosa containing Tn501 occurred within 60 s of HgCl(2) addition and was proportional to the amount of Hg(II) added. The new technique also allowed the detection of merA transcripts from the microbial community of a mercury-contaminated pond (Reality Lake, Oak Ridge, Tenn.). Significant differences in merA transcript abundance were observed between different locations associated with the lake. The results indicate that the new method is simple and rapid and can be applied to the study of mer gene expression of aquatic communities in their natural habitats.

Journal Article↗
PubMed1987

Radioenzymatic microassay for picogram quantities of serotonin or acetylserotonin in biological fluids and tissues.

This paper describes several modifications of the original radioenzymatic assay for serotonin which increase the sensitivity of the assay 20-fold as well as enhance its reliability. Using this method serotonin concentrations can be directly measured in biological examples without precleaning the sample. When compared to currently available methods this assay is specific and sensitive to approximately 1 pg of serotonin and can be used to measure serotonin levels in individual brain nuclei or microliter quantities of biological fluids. This assay can be easily adapted for the direct measurement of N-acetylserotonin. A large number of samples can be assayed in a single working day.

Acetylserotonin O-Methyltransferase↗
PubMed2006

Phase-aberration correction with a 3-D ultrasound scanner: feasibility study.

We tested the feasibility of using adaptive imaging, namely phase-aberration correction, with two-dimensional (2-D) arrays and real-time, 3-D ultrasound. Because of the high spatial frequency content of aberrators, 2-D arrays, which generally have smaller pitch and thus higher spatial sampling frequency, and 3-D imaging show potential to improve the performance of adaptive imaging. Phase-correction algorithms improve image quality by compensating for tissue-induced errors in beamforming. Using the illustrative example of transcranial ultrasound, we have evaluated our ability to perform adaptive imaging with a real-time, 3-D scanner. We have used a polymer casting of a human temporal bone, root-mean-square (RMS) phase variation of 45.0 ns, full-width-half-maximum (FWHM) correlation length of 3.35 mm, and an electronic aberrator, 100 ns RMS, 3.76 mm correlation, with tissue phantoms as illustrative examples of near-field, phase-screen aberrators. Using the multilag, least-squares, cross-correlation method, we have shown the ability of 3-D adaptive imaging to increase anechoic cyst identification, image brightness, contrast-to-speckle ratio (CSR), and, in 3-D color Doppler experiments, the ability to visualize flow. For a physical aberrator skull casting we saw CSR increase by 13% from 1.01 to 1.14, while the number of detectable cysts increased from 4.3 to 7.7.

Algorithms↗
PubMed1996

An enhanced feature extraction algorithm for EMG pattern classification.

We present an enhanced feature extraction algorithm which combines block and adaptive processing to identify motion command for the control of a prosthetic arm. The algorithm is capable of precise and stable feature extraction. A sample application with the block processing stationary model parameters is provided to evaluate the feasibility of the adaptive cepstrum vector extracted by the proposed algorithm for electromyographic (EMG) pattern classification.

Algorithms↗
PubMed2004

Continuous measurement of oxygen consumption during cardiopulmonary bypass: description of the method and in vivo observations.

BACKGROUND: Systemic oxygen consumption is not routinely measured during cardiopulmonary bypass, despite its potential benefits. We aimed to develop a noninvasive method to continuously measure oxygen consumption using respiratory mass spectrometry during hypothermic cardiopulmonary bypass in pigs. METHODS: Nine pigs weighing 18.5 (1.6) kg underwent hypothermic (32 degrees C) cardiopulmonary bypass for 180 minutes with 120 minutes of aortic cross clamping. An AMIS 2000 mass spectrometer (Innovision A/S, Odense, Denmark) was adapted for the on-line measurement of oxygen consumption by sampling the inlet and outlet gases of the membrane oxygenator together with measurement of the "expired" gas volume. RESULTS: Active cooling for 60 minutes reduced the venous blood temperature by 2.9 (0.8) degrees C and VO(2) by 0.70 (0.33) mL/kg/min. The 40-minute active rewarming restored the venous blood temperature by 4.4 (0.4) degrees C and oxygen consumption increased by 1.36 (0.33) mL/kg/min. There was wide interanimal variability, however, particularly at higher venous blood temperatures. Immediately after the release of aortic cross clamp, there was a noticeably acute increase in oxygen consumption in all the pigs (0.64 [0.21] mL/kg/min). CONCLUSIONS: A simple and safe adaptation of mass spectrometry allows continuous measurement of oxygen consumption during hypothermic cardiopulmonary bypass. The wide interindividual variations observed in this pilot study underscore the need to more accurately describe changes in oxygen consumption and how they are affected by temperature, oxygen delivery, and other interventions during cardiopulmonary bypass. As such, the technique may have an important role in clinical research and management of oxygen transport in patients undergoing cardiac surgery.

Animals↗