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2.
Sci Rep ; 12(1): 14603, 2022 Aug 26.
Article in English | MEDLINE | ID: mdl-36028538

ABSTRACT

This work presents the application of an experimental nematic liquid crystal (LC) mixture (1929) in a large aperture lens. The LC material is composed of terphenyl and biphenyl derivatives compounds with an isothiocyanate terminal group and fluorinated lateral substituents. The substitution with a strongly polar isothiocyanate group and an aromatic rigid core provides [Formula: see text]-electron coupling, providing high birefringence ([Formula: see text] at 636 nm and 23 °C) and low viscosity ([Formula: see text] = 17.03 mPa s). In addition, it also shows high values of birefringence at near infrared (0.318 at 1550 nm). The synthesis process is simple when comparing materials with high melting temperatures. The excellent properties of this LC mixture are demonstrated in a large aperture LC-tunable lens based on a transmission electrode structure. Thanks to the particular characteristics of this mixture, the optical power is high. The high birefringence makes this LC of specific interest for lenses and optical phase modulators and devices, both in the visible and infrared regions.

3.
Opt Express ; 30(8): 12237-12247, 2022 Apr 11.
Article in English | MEDLINE | ID: mdl-35472863

ABSTRACT

In this work, a technique to generate aspherical liquid crystal lenses with positive and negative optical power is experimentally demonstrated. The main enabling element is a micro-metric electrode with variable spatial size. This produces a decreasing resistance towards the lens centre that generates the desired voltage/phase profiles. Then, the voltage is homogeneously distributed across the active area of the lens by micro-metric concentric electrodes. As it is demonstrated, the phase shift can be controlled with voltages from 0 to 4.5 VRMS. As a result, parabolic profiles are obtained both for negative and positive optical powers. Furthermore, this approach avoids some disadvantages of previous techniques; parabolic profiles can be obtained with only one lithographic step and one or two voltage sources. Other complex aspherical profiles could be fabricated using the same technique, such as elliptical or hyperbolic ones.

4.
Poult Sci ; 99(6): 2833-2840, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32475416

ABSTRACT

Several genomic methods were applied for predicting shell quality traits recorded at 4 different hen ages in a White Leghorn line. The accuracies of genomic prediction of single-step GBLUP and single-trait Bayes B were compared with predictions of breeding values based on pedigree-BLUP under single-trait or multitrait models. Breaking strength (BS) and dynamic stiffness (Kdyn) measurements were collected on 18,524 birds from 3 consecutive generations, of which 4,164 animals also had genotypes from an Affymetrix 50K panel containing 49,591 SNPs after quality control edits. All traits had low to moderate heritability, ranging from 0.17 for BS to 0.34 for Kdyn. The highest accuracies of prediction were obtained for the multitrait single-step model. The use of marker information resulted in higher prediction accuracies than pedigree-based models for almost all traits. A genome-wide association study based on a Bayes B model was conducted to detect regions explaining the largest proportion of genetic variance. Across all 8 shell quality traits analyzed, 7 regions each explaining over 2% of genetic variance and 54 regions each explaining over 1% of genetic variance were identified. The windows explaining a large proportion of genetic variance overlapped with several potential candidate genes with biological functions linked to shell formation. A multitrait repeatability model using a single-step method is recommended for genomic evaluation of shell quality in layer chickens.


Subject(s)
Animal Husbandry/methods , Chickens/physiology , Egg Shell/physiology , Genome-Wide Association Study/veterinary , Genomics/methods , Animals , Bayes Theorem , Breeding , Chickens/genetics , Female , Genome , Male
5.
Poult Sci ; 98(1): 39-45, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30101314

ABSTRACT

Clutch traits were proposed as a more detailed description of egg-laying patterns than simple total egg production. In this study, egg production of 23,809 Rhode Island Red (RIR) and 22,210 White Leghorn (WL) hens was described in terms of number of clutches, average and maximum clutch size, age at first egg, total saleable egg production, and percentage of egg defects. Genetic parameters were estimated using a six-trait animal model. Of the phenotyped birds, 1433 RIR hens and 1515 WL hens were genotyped with line specific 50K Affymetrix Axiom single nucleotide polymorphism chips to perform genome-wide association analyses. Moderate heritabilities were estimated for clutch traits of 0.20 to 0.42 in the RIR line and 0.29 to 0.41 in the WL line. Average and maximum clutch size was positively genetically correlated with total saleable egg number in both lines. Genome-wide association analysis identified seven regions that were associated with egg production in the RIR line and 12 regions in the WL line. The regions identified were line and trait specific, except for one region on chromosome 6 from 28 to 29 Mb that influenced number of clutches and maximum and average clutch size in WL hens. Regions associated with egg production identified here overlapped with 260 genes, with some strong positional candidates based on gene ontology including WASH1, which is involved in oocyte maturation, NPVF, involved in regulation of follicle-stimulating hormone secretion, and FOXO3, involved in oocyte maturation and ovulation from the ovarian follicle. Confirmation of the role of these genes in regulation of egg production pattern will require further studies.


Subject(s)
Chickens/genetics , Oviposition/genetics , Animals , Chickens/physiology , Female , Genome-Wide Association Study , Genotype , Oocytes/growth & development , Oviposition/physiology , Ovum , Time Factors
6.
Animal ; 12(7): 1363-1371, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29103391

ABSTRACT

Two highly pathogenic avian influenza (HPAI) outbreaks have affected commercial egg production flocks in the American continent in recent years; a H7N3 outbreak in Mexico in 2012 that caused 70% to 85% mortality and a H5N2 outbreak in the United States in 2015 with over 99% mortality. Blood samples were obtained from survivors of each outbreak and from age and genetics matched non-affected controls. A total of 485 individuals (survivors and controls) were genotyped with a 600 k single nucleotide polymorphism (SNP) array to detect genomic regions that influenced the outcome of highly pathogenic influenza infection in the two outbreaks. A total of 420458 high quality, segregating SNPs were identified across all samples. Genetic differences between survivors and controls were analyzed using a logistic model, mixed models and a Bayesian variable selection approach. Several genomic regions potentially associated with resistance to HPAI were identified, after performing multidimensional scaling and adjustment for multiple testing. Analysis conducted within each outbreak identified different genomic regions for resistance to the two virus strains. The strongest signals for the Iowa H5N2 survivor samples were detected on chromosomes 1, 7, 9 and 15. Positional candidate genes were mainly coding for plasma membrane proteins with receptor activity and were also involved in immune response. Three regions with the strongest signal for the Mexico H7N3 samples were located on chromosomes 1 and 5. Neuronal cell surface, signal transduction and immune response proteins coding genes were located in the close proximity of these regions.


Subject(s)
Chickens , Disease Resistance , Influenza in Birds , Animals , Bayes Theorem , Chickens/genetics , Disease Outbreaks , Disease Resistance/genetics , Influenza A Virus, H5N2 Subtype , Influenza A Virus, H7N3 Subtype , Influenza in Birds/genetics , Mexico , United States
7.
Dentomaxillofac Radiol ; 43(8): 20140165, 2014.
Article in English | MEDLINE | ID: mdl-25182120

ABSTRACT

OBJECTIVES: To assess the prevalence of sella turcica anomalies on lateral cephalograms of children with malocclusion. To describe the craniofacial morphology in patients with sella turcica anomalies. METHODS: Lateral cephalograms obtained at ages 8-16 years (n = 431) were assessed for good visibility of cephalometric structures, including the sella turcica, and the absence of craniofacial congenital deformities; finally, 322 cephalograms were included and analysed. Subsequently, anomalies of sella turcica have been identified. Hypertrophic posterior clinoid process, hypotrophic posterior clinoid process and oblique contour of the floor were the abnormalities found that could not be classified based on literature. The study group consisted of 151 cephalograms with abnormal sella turcica, while the control group consisted of 171 cephalograms without any sellar pathology. Data normality has been tested using Shapiro-Wilk test. Correlations with age were made using Spearman correlation coefficient and those with sex were made using independence test with Yate's correction for continuity. Mann-Whitney test was used to compare between groups and subgroups. The level of significance has been established as p < 0.05. RESULTS: Sellar anomalies were found in 151 individuals (46.9%). Statistically significant differences between patients with normal and abnormal sellar morphology were found concerning: Pg:NB (p = 0.0009), 1+:NA (p = 0.0004) and 1-:NB (p = 0.012), indicating a more distal position of jaw structures in subjects with abnormal sella. CONCLUSIONS: The finding that almost 50% of children with malocclusion have sellar abnormalities confirms a general aetiology of malocclusion. Sella turcica assessment should be carried out during cephalometric analysis.

8.
J Anim Breed Genet ; 131(3): 173-82, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24628796

ABSTRACT

Discovery of genes with large effects on economically important traits has for many years been of interest to breeders. The development of SNP panels which cover the whole genome with high density and, more importantly, that can be genotyped on large numbers of individuals at relatively low cost, has opened new opportunities for genome-wide association studies (GWAS). The objective of this study was to find genomic regions associated with egg production and quality traits in layers using analysis methods developed for the purpose of whole genome prediction. Genotypes on over 4500 birds and phenotypes on over 13,000 hens from eight generations of a brown egg layer line were used. Birds were genotyped with a custom 42K Illumina SNP chip. Recorded traits included two egg production and 11 egg quality traits (puncture score, albumen height, yolk weight and shell colour) at early and late stages of production, as well as body weight and age at first egg. Egg weight was previously analysed by Wolc et al. (2012). The Bayesian whole genome prediction model--BayesB (Meuwissen et al. 2001) was used to locate 1 Mb regions that were most strongly associated with each trait. The posterior probability of a 1 Mb window contributing to genetic variation was used as the criterion for suggesting the presence of a quantitative trait locus (QTL) in that window. Depending upon the trait, from 1 to 7 significant (posterior probability >0.9) 1 Mb regions were found. The largest QTL, a region explaining 32% of genetic variance, was found on chr4 at 78 Mb for body weight but had pleiotropic effects on other traits. For the other traits, the largest effects were much smaller, explaining <7% of genetic variance, with regions on chromosomes 2, 12 and 17 explaining above 5% of genetic variance for albumen height, shell colour and egg production, respectively. In total, 45 of 1043 1 Mb windows were estimated to have a non-zero effect with posterior probability > 0.9 for one or more traits.


Subject(s)
Chickens/genetics , Chickens/physiology , Genome-Wide Association Study , Oviposition/genetics , Animals , Female , Genetic Variation , Genomics
9.
Br J Cancer ; 107(5): 793-9, 2012 Aug 21.
Article in English | MEDLINE | ID: mdl-22850551

ABSTRACT

BACKGROUND: To investigate whether copy number gain of MET or hepatocyte growth factor (HGF) affect trastuzumab sensitivity in HER2-positive metastatic breast cancer (MBC). METHODS: We analysed 130 HER2-positive MBC treated with trastuzumab-based therapy. MET and HGF gene copy numbers (GCN) were assessed by fluorescence in situ hybridisation (FISH) in primary breast cancer samples. Receiver operating characteristic analysis was applied to find the best cutoff point for both MET and HGF GCN. RESULTS: MET FISH-positive cases (N=36, mean 3.72) had a significantly higher trastuzumab failure rate (44.4% vs 16.0%; P=0.001) and a significantly shorter time to progression (5.7 vs 9.9 months; HR 1.74; P=0.006) than MET FISH-negative cases (N=94, mean <3.72). Hepatocyte growth factor GCN was evaluated in 84 cases (64.6%). Receiver operating characteristic analysis identified 33 HGF FISH-positive patients (mean HGF GCN 3.01). HGF FISH-positive status was significantly associated with higher risk of failure (30.3% vs 7.8%; P=0.007) as compared with HGF FISH-negative cases (N=51, mean <3.01). MET and HGF FISH-positive status was highly correlated (P<0.001) and combination of both biomarkers did not increase predictive value of either considered separately. CONCLUSION: High GCNs of MET and HGF associate with an increased risk of trastuzumab-based therapy failure in HER2-positive MBC.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Gene Dosage , Hepatocyte Growth Factor/genetics , Proto-Oncogene Proteins c-met/genetics , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Agents/administration & dosage , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Drug Resistance, Neoplasm , Female , Hepatocyte Growth Factor/metabolism , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Middle Aged , Prognosis , Proto-Oncogene Proteins c-met/metabolism , Receptor, ErbB-2/biosynthesis , Receptor, ErbB-2/metabolism , Retrospective Studies , Trastuzumab
10.
Euro Surveill ; 15(17)2010 Apr 29.
Article in English | MEDLINE | ID: mdl-20460085

ABSTRACT

We describe a local indigenous outbreak of measles in a susceptible Roma community, which occurred in Pulawy, a town of 50,000 citizens in the Lubelskie province (eastern Poland) during summer 2009. From 22 June to 30 August 2009, 32 measles cases were reported, and additionally nine possible cases were actively identified. A mass immunisation campaign was organised to stop measles transmission in the Roma community. Active surveillance of rash-febrile illnesses allowed documentation of the impact of mass immunisation in preventing further measles spread in the Roma community, and the surrounding population of Pulawy.


Subject(s)
Disease Outbreaks/prevention & control , Disease Outbreaks/statistics & numerical data , Measles/ethnology , Measles/prevention & control , Roma/statistics & numerical data , Humans , Incidence , Poland/ethnology , Population Surveillance , Risk Assessment/methods , Risk Factors
12.
Neoplasma ; 52(6): 464-8, 2005.
Article in English | MEDLINE | ID: mdl-16284690

ABSTRACT

A 65-kDa tumor-associated protein (P65) is a potential non- specific tumor marker expressed by many types of tumor cells. Our recent studies indicate that P65 gene expression is connected with poor prognosis for the patients with colorectal cancer. In the present study P65 gene expression was determined by means of RT-PCR in the group of 22 gastric cancer and adjacent normal gastric mucosa. Its presence was correlated with some parameters of clinical staging. P65 gene expression was also determined in 102 tissue antral gastric endoscopic biopsy specimens from the patients suspected of H. pylori infection. The presence of H. pylori infection was determined by urease test. We found that in the group of gastric cancers, similarly to colorectal cancer, P65 gene expression was connected with poor clinicopathological parameters as T3, lymph nodes and distant metastases. There was no dependence between P65 gene expression and H. pylori infection. However, more often P65 gene expression was detected in the group of infected men than women. There was also a statistically significant dependence between age and P65 gene expression in the group of people above 60 years old. It could be then postulated that P65 gene expression is connected with poor prognosis for the patients suffering from gastric cancer and that this expression does not depend on H. pylori infection.


Subject(s)
Helicobacter Infections/genetics , Helicobacter Infections/microbiology , Helicobacter pylori/pathogenicity , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology , Transcription Factor RelA/genetics , Adult , Biopsy , Female , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Helicobacter Infections/metabolism , Humans , Lymph Nodes/pathology , Male , Middle Aged , Neoplasm Invasiveness/pathology , Prognosis , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Stomach Neoplasms/metabolism , Transcription Factor RelA/metabolism
13.
J Dairy Sci ; 87(11): 3925-7, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15483176

ABSTRACT

New molecular techniques focused on genome analysis open new possibilities for complex evaluation of economically important traits in farm animals. Milk production traits are typical quantitative characteristics controlled by a number of genes. Mutations in their sequences may alter animal performance as well as their breeding values. In this study, we investigated the effect of 3 restriction fragment length polymorphisms (RFLP): HphI, Kpn2I, and Sau3AI in the leptin gene, on bull breeding values for milk, fat, and protein yield, and fat and protein content. One hundred seventeen Polish Black and White AI bulls were genotyped. Pedigree analysis indicated a relatively close relationship between the bulls. Statistical analysis indicated that the HphI polymorphism has a significant effect on milk and protein yield. Animals with the TT genotype had approximately 2x higher estimated breeding values for milk and protein yields. No effect was found for the other 2 polymorphisms.


Subject(s)
Cattle/genetics , Lactation/genetics , Leptin/genetics , Milk Proteins/biosynthesis , Milk/chemistry , Polymorphism, Genetic , Animals , Breeding , Cattle/physiology , Female , Genotype , Lactation/physiology , Male , Milk/metabolism , Milk Proteins/genetics
14.
J Evol Biol ; 17(2): 312-21, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15009265

ABSTRACT

Seasonal dynamics of the abundance, sexual reproduction and genetic architecture in a Daphnia hyalina-galeata hybrid complex were studied in the large and deep Lake Constance. We found evidence for the occurrence of first and second order hybridization. Our study revealed strong differences between the parental species not only regarding their seasonal dynamics, genetic architecture and diversity, but also their sexual reproductive behaviour. The overwintering D. hyalina showed low genetic diversity, no genetic differentiation during the season, and reproduced sexually in autumn, whereas D. galeata reached higher levels of genetic diversity, reproduced sexually in early summer, and exhibited changes in genetic structure during the season, but was only present from spring to autumn. However, in both species sexual reproduction was a rare event, and daphnids, including hybrids, reproduced predominantly asexually. This allows long-term persistence of hybrids as well without continuing hybridization events. Within all variables studied, F1 and F2 hybrids showed an intermediate pattern, whereas proposed backcross hybrids were more similar to their respective parentals. These differences in phenotype as well as significant differences in pairwise Fst values between parentals suggest that gene flow seems to be relatively low in the Lake Constance hybrid system. We found evidence for unidirectional introgression by backcrossing from D. galeata to D. hyalina and found a decrease in at least one of the proposed introgressed alleles in the hyalina-backcross while the season progressed. Our findings suggest allochronic differentiation within this hybrid population and different microevolutionary trajectories of the parental species, which will be discussed in the light of the ongoing reoligotrophication process of Lake Constance.


Subject(s)
Daphnia/genetics , Daphnia/physiology , Genetics, Population , Hybridization, Genetic , Seasons , Animals , Crosses, Genetic , Fresh Water , Gene Frequency , Genotype , Germany , Isoenzymes , Population Dynamics , Reproduction/physiology , Species Specificity
15.
Appl Microbiol Biotechnol ; 65(1): 18-24, 2004 Jul.
Article in English | MEDLINE | ID: mdl-14758516

ABSTRACT

Several monitoring methods used to predict viable cell density have been the subject of extensive studies, including oxygen uptake rate, carbon dioxide evolution rate, optical density, NADH-dependent fluorescence and relative permittivity measurement. We propose intracellular ATP determination by bioluminescence assay to monitor the progress of baculovirus infection and recombinant protein production in insect cell cultures. We found that the ATP content in viable cells increased after virus addition. The increase in the ATP level was observed until the maximum recombinant protein accumulation was reached. At maximum product yield, the specific ATP content significantly decreased. Results obtained in both batch and fed-batch cultures demonstrated that the specific ATP level could be considered as a good indicator of recombinant protein productivity. Monitoring the cellular ATP content after viral infection makes it possible to define the optimum time for product harvest. The main advantage of applying the ATP assay as an index of the progress of infection and recombinant protein synthesis is its short time and sensitivity.


Subject(s)
Adenosine Triphosphate/metabolism , Monitoring, Physiologic/methods , Recombinant Proteins/biosynthesis , Transgenes/physiology , Animals , Baculoviridae/genetics , Biotechnology/methods , Cell Division , Cells, Cultured , Genetic Vectors , Lepidoptera/cytology , Recombinant Proteins/genetics
16.
J Biomater Sci Polym Ed ; 12(9): 1051-8, 2001.
Article in English | MEDLINE | ID: mdl-11787521

ABSTRACT

The exclusion limit expressed as the largest pore size of capsules composed of hydrogel Ca-alginate membrane and hydroxy-propyl-ammonium starch liquid core considered as the immunoprotective system has been determined by means of inverse size exclusion chromatography with dextran molecular weight standards. The exclusion limits of the capsules were not influenced by the change of starch concentration in the core solution from 4 to 6% but were influenced by the change in alginate concentration in the membrane from 0.5 to 1.0%, causing the membranes to be less permeable. It was found that the diameter of the largest pores in hydrogel membranes was in the range 7.2-8.0 nm. Based on the relationship between solute size and its molecular weight, the capsules had an approximate exclusion limit of 21-25 kD for dextran and 78-103 kD for protein, which is sufficient to block the antibodies penetrating through the membrane.


Subject(s)
Capsules/chemistry , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Alginates/chemistry , Calcium/chemistry , Chromatography, Gel/methods , Glucuronic Acid , Hexuronic Acids , Membranes, Artificial , Molecular Weight
17.
Ginekol Pol ; 71(9): 1139-43, 2000 Sep.
Article in Polish | MEDLINE | ID: mdl-11082991

ABSTRACT

The aim of the study was the assessment of serum concentrations of selected neoplasmatic markers: CA15-3, TPS and CEA in women with established diagnosis of benign breast disease (BBD) using hormone replacement therapy (HRT) for average 3 years. 120 women with BBD were divided to 2 groups: HRT-users (n1 = 24) and HRT-non-users (n2 = 96). 31 healthy, regularly menstruating, age-matched women served as control group. Concentrations of all markers were measured with immunoradiometric methods. In all groups serum concentrations of measured markers were within normal range. We conclude that hormone replacement therapy has no influence on serum concentrations of CA15-3, TPS and CEA.


Subject(s)
Breast Neoplasms/blood , Carcinoembryonic Antigen/blood , Mucin-1/blood , Tissue Polypeptide Antigen/blood , Adult , Biomarkers, Tumor/blood , Breast Neoplasms/diagnosis , Female , Hormone Replacement Therapy , Humans , Middle Aged
18.
Eur J Vasc Endovasc Surg ; 20(1): 21-4, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10906292

ABSTRACT

OBJECTIVES: To assess the effect of cryopreservation on the elasticity and compliance of arterial allografts. MATERIALS AND METHODS: Iliofemoral segments of arteries and veins harvested from multiorgan donors were divided into two groups: fresh-control, tested for 24 hours after harvesting, and cryopreserved in liquid nitrogen after pretreatment with 20% dimethylsulphoxide and stored for an average time of 22 days. Vessel wall elastic properties were evaluated from the stress-strain relationship in a specially designed test cell fixed to the Instron Universal Testing Machine. RESULTS: The elastic modulus of the artery control group (1.54+/-0.33 MPa, n=20) was not significantly different from the cryopreserved group (1.69+/-0.61 MPa, n=15). Similarly, values for unfrozen veins (3.11+/-0.65 MPa, n=47) were not significantly different from those of frozen samples (2.71+/-0.85 MPa, n=38). Control compliance (6. 86+/-1.79x10(-5)%/Pa, for arteries; 3.84+/-0.81x10(-5)%/Pa, for veins) was similar to that of the cryopreserved group (6.66+/-1. 80x10(-5)%/Pa, for arteries; 4.16+/-1.21x10(-5)%/Pa, for veins). CONCLUSIONS: Cryopreservation maintains the important elastic properties of arterial and venous allografts during average storage time of 22 days.


Subject(s)
Cryopreservation , Muscle, Smooth, Vascular/transplantation , Vasodilation/physiology , Biomechanical Phenomena , Compliance , Dimethyl Sulfoxide/pharmacology , Elasticity , Humans , Iliac Artery/physiopathology , Iliac Artery/transplantation , Iliac Vein/physiopathology , Iliac Vein/transplantation , Muscle, Smooth, Vascular/physiopathology , Tissue Banks , Transplantation, Homologous
19.
Biochem Eng J ; 6(1): 41-44, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-10908867

ABSTRACT

The overall diffusion coefficients for several low molecular weight solutes, such as glucose, fructose, sucrose, lactose, and vitamin B(12) have been determined in Ca-alginate membrane liquid-core capsules using the unsteady-state method following the release of solutes from the capsules to a well-stirred solution of limited volume. The diffusion coefficients obtained for saccharides were 5-20% lower than the corresponding diffusivity in water while for vitamin B(12) about 50% that of water. The diffusion coefficients of the investigated capsules were not influenced by the change in alginate concentration in the capsule membrane from 0.5 to 1.0%. Lower diffusivities and higher deviations from the diffusivity in water were obtained for higher molecular weight solutes.

20.
Gerontologist ; 38(6): 743-8, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9868854

ABSTRACT

The Michigan Aging Services System, a World Wide Web-based information system, was developed for practicing gerontologists in the state of Michigan. A participatory design framework adapted from the software development literature guided the development process. Users from Michigan's aging network participated in the development process. Design data were collected using multiple techniques. The system's content was developed with extensive input from actual users. The content emerged into four main categories: News and Current Events, General Information, Policy and Program Information, and Population Information. The system content is briefly compared to that of World Wide Web sites published by other state units on aging.


Subject(s)
Aging , Health Services for the Aged , Information Systems , Internet , Michigan , Workforce
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