bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D micro‐CT analysis of the interface voids associated with Thermafil root fillings used with AH Plus or a flowable MTA sealer
Authors: Gandolfi M. G. , Parrilli A. P. , Fini M. , Prati C. , Dummer P. M. H. 
Published: October 2012

AbstractAimTo investigate nondestructively the percentage of 3D voids and marginal gaps in a pre‐defined interface volume of interest (VOI) within root fillings produced by Thermafil Obturators with either a hydrophobic epoxy‐resin‐based sealer (AH Plus) or a hydrophilic flowable calcium‐silicate sealer [mineral trioxide aggregate (MTA) Flow].MethodologySixteen single root canals from extracted premolar teeth were prepared with ProTaper rotary instruments, randomly allocated into two groups (n = 8) and filled with size 30 Thermafil Obturators in association with AH Plus or MTA Flow sealers. The filled roots were stored at 37 °C in 5 mL of Hank's balanced salt solution (HBSS) used to represent body fluids and scanned after 7 days and 6 months using a high‐resolution micro‐CT. From each root, images of 3000 sections were analysed in 3D and binarized using a high‐resolution micro‐CT (4‐μ resolution). The 3D distribution of voids (porosity and marginal gaps) at the gutta‐percha‐sealer‐dentine interface was detected through a threshold grey level and expressed as percentage of the 40‐μ‐thick pre‐defined interface VOI (20 μ of interface dentine and 20 μ of gutta‐percha/sealer). A method of analysis based on the root canal segmentation was used, and coronal, middle and apical thirds considered separately. The percentage of 3D void volume was compared statistically using one‐way anova (significance for P < 0.05). Environmental Scanning Electron Microscope with Energy Dispersive X‐ray (ESEM‐EDX) analysis was performed on the surface of both sealers after soaking in HBSS.ResultsMicro‐CT detected gaps at the dentine‐sealer interface in both groups. Void volumes wider than 10.21 μm3 with 1.35 μm diameter were detected. Cul‐de‐sac‐type voids (blind pores) and through‐and‐through voids (continuous pores) were discriminated. The apical thirds had a significantly lower 3D void volume (P < 0.05) than the middle and coronal thirds. The 3D void volume reduced significantly (P < 0.05) over time. ESEM‐EDX analysis revealed that MTA Flow sealer created a dense apatite layer after 7 days of immersion in HBSS, whilst only sparse calcium phosphate deposits were detected on AH Plus even after 28 days.ConclusionsMicro‐CT proved to be a powerful nondestructive 3D analysis tool for visualizing the porous internal microstructure of dental/endodontic materials at the interface with dentine. The proportion of voids was least in the apical third of root canals. Voids reduced over time in the presence of simulated body fluid.
Coeliac disease – women's experiences in everyday life
Authors: Jacobsson Lisa R , Hallert Claes , Milberg Anna , Friedrichsen Maria 
Published: October 2012

Aims and objectivesTo describe what life is like as a woman living with coeliac disease.BackgroundThe therapy for coeliac disease is a gluten‐free diet, and if sufferers keep strictly to this, it is suggested that they will stay well. However, previous studies point out that people who are treated for coeliac disease, particularly women, experience various kinds of inconvenience in relation to having coeliac disease and to being treated with gluten‐free diet.DesignA qualitative research design was chosen.MethodsA phenomenological approach as devised by Giorgi was used. Tape‐recorded qualitative interviews with a total of 15 women who were being treated for coeliac disease were conducted in 2008 in Sweden.ResultsThe results demonstrated that coeliac disease can influence women's lives in different ways. The general structure of being a woman with coeliac disease was described as a striving towards a normalised lifeworld. Three conditions necessary to achieve a normalised life were described, namely being secure, being in control and being seen and included.ConclusionUnderstanding factors affecting the ability to live with coeliac disease as normally as possible can help caregivers, and others, to support these women in their aims.Relevance to clinical practiceNurses should help women to adopt facilitating thoughts in relation to the disease and, in so doing, help them to select appropriate coping strategies.
Heart or lung transplanted patients' retrospective views on information and support while waiting for transplantation
Authors: Ivarsson Bodil , Ekmehag Björn , Sjöberg Trygve 
Published: October 2012

Aims and objectivesTo describe the patients' retrospective experiences of the information and support they received while on the heart or lung transplant waiting list.BackgroundPatients differ in the way that they cope with the time spent waiting for a heart or lung transplant. Patients must already before the transplantation be taught about a new lifestyle, risk factors, medication, food restrictions and exercise, so they can take an active role and responsibility for disease management after transplantation. Little is known about patients' experiences of information and support in these situations.DesignQualitative descriptive design.MethodsSixteen patients (16–67 year) were strategically selected from one transplant centre in Sweden and interviewed six months after heart or lung transplantation. Using content analysis, transcribed data were organised into subcategories that reflected emerging categories.ResultsThree categories that describe patients' experiences of information and support have been identified: ‘Achieving confidence and trust by information and support’, ‘Experiencing a lack of input and understanding’ and ‘Struggling with a life‐threatening illness and an insecure future’. Each category consists of different subcategories.ConclusionsInformation and support in connection to heart or lung transplantation are a complex and multifaceted issue involving patient‐related, family‐related, disease‐related and treatment‐related factors as well as experiences related to the social situation, the healthcare system and society. Transplant patients are very vulnerable, and a deeper understanding of patients' experiences should help healthcare providers in optimising the care for these very sick patients.Relevance to clinical practiceA holistic approach to the patient is necessary in meeting the needs of patients with chronic illness, especially patients with children at home, as well as the needs of their families. An important implication is the necessity to enhance awareness about transplant patients in society in general, in particular in other institutions, by sharing knowledge and by improving cooperation.
Nutrition screening by nurses in dialysis
Authors: Bennett Paul N , Miller Michelle D , Woodman Richard J , Hill Kathleen , Murray Susan , Gleadle Jonathon M 
Published: October 2012

Aims and objectivesTo determine whether a nurse‐completed dialysis nutritional screening tool improves referral rates for nutritional support and compare nutrition sensitive biochemical indices, mortality rates and patient‐centred quality of life outcomes between referred and non‐referred dialysis patients.BackgroundPeople with chronic kidney disease requiring dialysis are nutritionally at risk. Nutrition screening has been shown to identify dialysis patients who are nutritionally at risk to refer to dietitian expertise.DesignProspective cluster‐randomised control trial.MethodsMonthly nurse‐completed nutrition screening was completed for six consecutive months using a validated four‐item instrument measuring weight change, serum phosphate, serum potassium and appetite. Participants (n = 81) were haemodialysis patients from four satellite haemodialysis centres in one Australian metropolitan health service. Primary outcome measure was rate of referral to dietetic services for nutrition support for intervention vs. control groups at six months. Secondary outcome measures were blood pressure, biochemical indices and mortality for referred vs. non‐referred patients at six and nine months, and generic and dialysis‐specific quality of life for referred vs. non‐referred at nine months was examined.ResultsThere were three times as many dietetic referrals in the intervention group than in the control group (26·3 vs. 9·3%). Serum phosphate increased significantly more in the referred patients than the non‐referred patients. There were no clinically significant changes between groups in quality of life, blood pressure, mortality rates or other biochemical indices at either six or nine months.ConclusionNurse‐completed nutritional screening can lead to appropriate dietetic referrals for nutritional support by nutritional expert clinicians.Relevance to clinical practiceThis study is the first to demonstrate that monthly systematic nurse‐completed nutritional screening can facilitate appropriate dietetic referrals that may lead to increased nutritional care for people in satellite dialysis centres.
Methodological basis for an autoradiographic demonstration of insulin receptor sites on the surface of whole cells: a study using light‐ and scanning electron microscopy
Authors: Junger E. , Bachmann L. 
Published: October 2012

SUMMARYAn autoradiographic technique is described which allows, on whole cells, the determination of the number of receptor sites which are occupied by 125I‐insulin according to defined binding conditions. Glutaraldehyde fixation prevents the dissociation of the bound tracer from the receptor, which is the basis for a quantitative correlation between biochemical and autoradiographical data.The homogeneous coating of whole cells with a thin emulsion layer, which was required for these experiments, was achieved by a stripping film technique. An accurate judgment of the coating was possible only with scanning electron microscopic (SEM) techniques. As observed in the SEM, the photographic layer was smooth, uniform and in good contact with the top of the cell. The signal measured in this area was analysed. The majority of the grains also originated from the top side of the cell surface, despite the evidently three‐dimensional distribution of the label. As determined in test specimens, 80–85% of the grains originated from 3–4 keV electrons. Due to the short range of these electrons, the grains represent the distribution of the label on the part of the cell surface which is in close contact with the emulsion layer. 15–20% of the grains originated from β‐decays with higher energies and add partially to the background. According to these data a determination of the number of receptor sites per unit area of plasma membrane (receptor density) is possible in the surface area of the cell top.Both light microscopy (LM) and SEM were used to analyse autoradiographs. LM analysis is possible in principle but the analytical facilities of SEM are yet superior for the identification of silver grains. The registration of the grains is further facilitated in SEM because of the very large depth of focus.
A procedure for minimizing cellular shrinkage in electron microscope preparation: a quantitative study on frog gall bladder
Authors: Rostgaard J. , Tranum‐Jensen J. 
Published: October 2012

SUMMARYNomarski differential interference contrast microscopy of whole‐mount preparations of frog gall bladders has been used for light microscopic measurement of epithelial cell luminal area. Measurements were performed: in buffer after fixation, and in cured Epon after step‐by‐step and after continuous dehydration and infiltration procedures. Sections cut perpendicularly to the luminal surface were used for the measurement of epithelial cell height. From these measurements epithelial cell mean volumes were calculated. The comparative measurements showed that a step procedure results in significantly smaller cellular dimensions than does a procedure of slow and continuous change of concentration of the preparative media, the difference in epithelial cell mean volume being about 40%. Electron microscopy of thin sections of continuously processed specimens showed superior ultrastructural preservation of cytoplasmic density and microplical arrangement compared to the step processed counterparts. The principle was successfully applied in processing for scanning electron microscopy of osmotically extremely fragile preparations of erythrocyte ghosts; similarly, formation of the luminal cobblestone appearance of gall bladder epithelium was prevented. The present studies support the view that at least part of the volume shrinkage through the procedures of embedding is caused by osmotic gradients set up in the tissue.
The preparation of human spermatozoa for analytical and scanning electron microscopy
Authors: Sheppard B. L. , Sheppard Uta , Harrison R. F. 
Published: October 2012

SUMMARYHuman spermatozoa have been prepared for electron microscopy comparing methods of specimen preparation and support mechanisms which enable investigations of elemental composition related to changes in surface morphology. A technique combining SEM of critical‐point dried, gold coated spermatozoa mounted on glass cover slips with analytical STEM of air dried, carbon coated spermatozoa mounted on formvar coated nickel grids proved most reliable and reproducible. The relative advantages and disadvantages of the methods, and the results obtained from them, are discussed.
A simple apparatus for use in matched freeze‐fracture replication
Authors: Wilkinson M. J. , Northcote D. H. 
Published: October 2012

SUMMARYAn apparatus for use in matched freeze‐fracture replication and suitable for attachment to the cold table of Balzers freeze‐etch units is described. It comprises a hinge and six pairs of copper support plates. The latter are detachable from the main assembly and designed to obtain the maximum cooling rate of the specimen. The construction and operation of the apparatus is relatively simple and inexpensive and it has proved a reliable and efficient means of performing matched replication of cell suspensions.
A new comparison macroscope
Authors: Klingenberg Anders 
Published: October 2012

SUMMARYThis paper gives a brief historical view of the origin, development, and application of the comparison macroscope, within the field of criminal technique. The background for developing a new comparison macroscope as well as the requirements for it are explained, and a decription is given of how the requirements were fulfilled. Finally the technical data for the new comparison macroscope and some applications are given.
Improvements that facilitate the operation of the Corinth 275 electron microscope
Authors: Webb M. J. W. 
Published: October 2012

SUMMARYDetails are given of modifications to the Corinth 275 electron microscope providing illumination of the magnification scale and locking of the astigmatism controls. The construction of a loading jig suitable for use with specimen rods of this microscope is described. Operational procedures that allow accurate setting of filament height and centering and also give some compensatory correction of condenser astigmatism are discussed.
Structure analysis of sputter‐coated and ion‐beam sputter‐coated films: a comparative study
Authors: Kemmenoe B. H. , Bullock G. R. 
Published: October 2012

SUMMARYGold, platinum and tungsten films were deposited by low energy input (7 mA, 450 V), or high deposition rate (80 mA, 1500 V), diode sputter coating and by ion beam sputter coating. Film structures on Formvar coated grids and on the surface of coated erythrocytes, resin embedded, sectioned, and recorded at high magnification in a TEM were compared using computer‐assisted measurements and analysis of film thickness and grain size.The average grain size of the thinnest gold and platinum films was relatively independent of the mode or rate of deposition but as the film thickness increased, significant differences in grain size and film structure were observed.Thick platinum or gold films deposited by low energy input sputter coating contained large grain size and electron transparent cracks; however, more even films with narrower cracks but larger grain size were produced at high deposition rates. Ion beam sputter coated gold had relatively large grain size in 10 nm thick films, but beyond this thickness the grains coalesced to form a continuous film. Platinum films deposited by ion beam sputter coating were even and free of electron transparent cracks and had a very small grain size (1–2 nm), which was relatively independent of the film thickness.Tungsten deposition either by low energy input or ion beam sputter coating resulted in fine grained even films which were free of electron transparent cracks. Such films remained granular in substructure and had a grain size of about 1 nm which was relatively independent of film thickness. Tungsten films produced at high deposition rates were of poorer quality.We conclude that thick diode sputter coated platinum and gold films are best deposited at high deposition rates provided the specimens are not heat sensitive, the improvement in film structure being more significant than the slight increase in grain size. Thick diode or ion beam sputter coated gold films should be suitable for low resolution SEM, and thin discontinuous gold films for medium resolution SEM. Diode sputter coated platinum should be suitable for medium resolution SEM and ion beam sputter coated platinum for medium and some high resolution SEM. 1–5 nm thick tungsten films, deposited by low energy input or ion beam sputter coating should be suitable for high resolution SEM, particularly where contrast is of less importance than resolution.
Improved method for transmission electron microscopy of ciliated cell monolayers maintained on gas‐permeable membranes
Authors: Gabridge Michael G. , Dougherty Edward P. 
Published: October 2012

SUMMARYA new method is described for preparing thin sections for transmission electron microscopy of ciliated respiratory epithelial cells cultivated in vitro on Teflon membranes. Hamster tracheal explant cultures were treated with collagenase to promote epithelial migration. Patches of monolayer growth occurred in the vicinity of the explants when the latter were incubated on FEP‐etched Teflon membranes in Chamber/Dishes. Cells in the monolayer maintained a high degree of differentiation as evidenced by active ciliary motion. The monolayer was fixed and processed in situ. During the embedding process the chamber was supported on a solid Teflon cylinder to keep the membrane taut as it was heated to polymerize the resin. The membrane was removed and the monolayered cells were re‐embedded and sectioned. Electron microscopic examination of cultures revealed clear cell profiles on a flat, even basal plane. This method provides for a normal spatial configuration of cells in a monolayer format, and should prove useful for electron microscopy studies of any cells cultured on flexible films.
Bidirectional shadowing in freeze‐etching
Authors: Willison J. H. M. , Moir R. D. 
Published: October 2012

SUMMARYBidirectional shadowing in freeze‐etching may be achieved by firing an electron‐beam shadowing source, rotating the specimen stage through a desired angle, and re‐firing the shadowing source. It is demonstrated that portrait shadow‐casting, which permits information to be drawn from much of the specimen region lying within primary shadows, can be readily achieved using a 90° specimen rotation. With 180° specimen rotation, particle‐size analysis is feasible. Particle‐height analysis is demonstrated using membrane‐associated particles as an example. Data from suitable sets of micrographs can also be used for the estimation of particle‐width exaggeration due to the accumulation of the shadowing‐metal cap. Fibre‐width analysis, using the linear regression method, is demonstrated by a study of native cellulosic microfibrils. Mean microfibril widths were found to be 5.5–7.0 nm.
Effects of hydration on the surface morphology of urediospores
Authors: Read N. D. , Beckett A. 
Published: October 2012

SUMMARYChanges in the surface morphology of mature urediospores of Uromyces viciae‐fabae have been studied with respect to different preparative procedures for the scanning electron microscope. Specimens were examined in the critical point‐dried, freeze‐dried and frozen‐hydrated states. Dried urediospores were significantly different in appearance from those which were hydrated. Shrinkage probably accounted for some of the surface features of dried spores, particularly amongst those which had been critical point‐dried. No significant effects on spore surface texture resulted from chemical immersion fixation, chemical vapour fixation, dehydration or the mode of sputter‐coating. It is suggested that the presence or absence of unfreezable water, involved in maintaining the structural stability of polymers which provide the specimen surface with its characteristic morphology, may have an important influence on the gross texture of cell surfaces as viewed with the scanning electron microscope.
The use of an ultra‐low viscosity medium (VCD/HXSA) in the rapid embedding of plant cells for electron microscopy
Authors: Oliveira Luis , Burns Alan , Bisalputra Thana , Yang Kung‐Chi 
Published: October 2012

SUMMARYThe VCD/HXSA ultra‐low viscosity medium is characterized by a viscosity of only 20 cps at 298 K. This is extremely useful for rapid embedding schedules and facilitates cutting large sections even from difficult materials. The suitability of this medium for ultrastructural studies is tested with plant specimens ranging from soft, highly vacuolated parenchymatous tissue to hard thick‐walled cells impregnated with a variety of substances or covered with mucilage. The results, when compared with those from similar materials infiltrated with Spurr's and Epon embedding media, show that the general preservation of the cellular structure is comparable for all the three media tested. In addition, embeddment in VCA/HXSA medium results in better preservation of some vacuolar features and in the reduction of plasmolysis.
Low temperature scanning electron microscope studies of mouse small intestine
Authors: Carr K. E. , Hayes T. L. , McKoon M. , Sprague M. , Bastacky S. J. 
Published: October 2012

SUMMARYEtched frozen hydrated specimens of mouse small intestine have been examined with low temperature scanning electron microscopy as a preliminary to X‐ray microanalysis. Recognizable images have been obtained of most of the known histological features of the gut. Nuclear and cytoplasmic details were often seen. Ice crystal damage was evident, although the degree of artefact depended on the cell type being examined and also varied from cell to cell or within cells.The same specimens were later examined with resin light microscopy and transmission electron microscopy. These two techniques confirmed that preservation was adequate for identification of cells and tissues, although cavities were seen, representing ice crystal damage.These preliminary results indicate that SEM of etched, frozen, hydrated specimens provides adequate identification of cellular detail to allow further work using X‐ray microanalysis to be carried out.
A method for processing polymeric beads for critical point drying
Authors: Takahashi Kiyoshi , Tavassoli Mehdi 
Published: October 2012

SUMMARYPolymeric beads are increasingly being used for surface studies. Processing of these beads for critical point drying (CPD) poses a problem since these beads must be handled in suspension. For this processing, a method has been described here which relies on a capsule made by an ordinary micropipette tip covered on the end by parafilm and on the other by a filter paper which permits the exchange of fluid without the loss of beads.