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J H Larsen

Publications and source records attributed to J H Larsen.

At least 19 recordsLinked to original sources
PubMed2001

Measurement of the energetics of metal film growth on a semiconductor: Ag/Si(100)-(2 x 1).

The first direct calorimetric measurements of the energetics of metal film growth on a semiconductor surface are presented. The heat of adsorption of Ag on Si(100)-(2 x 1) at 300 K decreases from approximately 347 to 246 kJ/mol with coverage in the first monolayer (ML) due to overlap of substrate strain from nearby Ag islands. It then rises quickly toward the bulk sublimation enthalpy (285 kJ/mol) as 3D particles grow. A wetting layer grows to 1.0 ML, but is metastable above approximately 0.55 ML and dewets when kinetics permit. This may be common when adsorbate islands induce a large strain in the substrate surface nearby.

Journal Article↗
PubMed2000

Three-dimensional whole body imaging of spin probes in mice by time-domain radiofrequency electron paramagnetic resonance.

Imaging of stable paramagnetic spin probes in phantom objects and in vivo was evaluated using a RF time domain EPR spectrometer/imager operating at 300 MHz. Projections were collected using static magnetic field gradients and images were reconstructed using filtered back-projection techniques. Results from phantom objects containing approximately 10(17) spins of stable paramagnetic probes with single narrow EPR spectra provide three-dimensional spatial images with resolution better than 2 mm. When the spin probe was administered to mice, the spin probe accumulation was temporally observed in the thoracic, abdominal, and pelvic regions. A three-dimensional image (from 144 projections) from a live mouse was collected in 5 min. Using fiducial markers, the spin probe accumulation in organs such as liver, kidney, and bladder could be observed. Differences in the oxygen status between liver and kidney were observed from the EPR images from mice administered with spin probe, by treating the time-domain responses with convolution difference approach, prior to image reconstruction. The results from these studies suggest that, with the use of stable paramagnetic spin probes and time-domain RF EPR, it is possible to perform in vivo imaging on animals and also obtain important spatially resolved physiologic information.

Animals↗
PubMed1999

["The consultation lab"--training clinical communication].

Discourse is the doctor's most essential tool. Since 1992, 500 Danish GPs have participated in "The consultation process I" and videosupervision in Greece. Participants are divided into groups of six. Each group works in a virtual consultation lab in which doctor-patient role plays are videotaped and supervised according to a specific matrix. In this experimental setting we have further sophisticated the nine phases (the P-R-A-C-T-I-C-A-L model) of the consultation process and improved our matrix for group supervision of video sessions. Typical individual pitfalls in doctor-patient communication have been demonstrated. Participant doctors were allowed to freely explore individual styles, and then establish how they were perceived by their "patients'"; they have learned how patient experience of a consultation varies. Furthermore, the courses helped to create networks: several groups met later, and a great many of these GPs have joined medical student tutoring. This way, the courses have contributed to more efficient work practices and job satisfaction, to professional advances, and to a lasting of the quality of upgrading in general practice.

Communication↗
PubMed1998

Postembryonic ontogeny of the spadefoot toad, Scaphiopus intermontanus (Anura: Pelobatidae): skeletal morphology.

Postembryonic skeletal ontogeny of the pelobatid frog Scaphiopus intermontanus is described based on a developmental series of cleared-and-stained, whole-mount specimens. The focus is on laboratory-reared individuals fed a herbivorous diet as larvae. Although there is variation in the timing of ossification of individual skeletal elements relative to developmental stages based on external morphological criteia, the sequence of skeletal development generally is conservative. Compared with its close relative, S. bombifrons, ossifications that occur during prometamorphosis tend to be slightly delayed in S. intermontanus; however, cranial bones that ossify during late metamorphic climax in S. intermontanus are delayed until post-metamorphosis in S. bombifrons. The differences in timing between the two species are consistent, however, with differences observed between two developmental series of S. intermontanus raised at two different temperatures. Noteworthy features of skeletal development in S. intermontanus include: 1) presence of palatine ossifications that form from independent centers of ossification and soon fuse with the postnarial portion of the vomers to form the compound vomeropalatine bones; 2) compound sphenethmoid that may arise from four or more endochondral centers of ossification and one dorsal, dermal center of ossification; and 3) presence of transverse processes and vestigal prezygapophyses on the first postsacral vertebra. The morphology of the larval orbitohyoideus and interhyoideus muscles is compared. The record of skeletal ontogeny and muscle morphology presented herein for the herbivorous larval morph can serve as a baseline for comparisons with the ontogeny of the carnivorous larval morph of Scaphiopus.

Animals↗
PubMed1997

P-R-A-C-T-I-C-A-L: a step-by-step model for conducting the consultation in general practice.

BACKGROUND: It has been shown that when patients are unable to express all their major concerns, they are less likely to follow the physician's prescribed treatment plan and they are less satisfied. On the other hand, the GP has a limited amount of time to elicit all the appropriate information and must ask certain questions about the biological aspects of the illness in order to carry out her professional responsibilities. By acting in a patient-centred way, first enabling the patient to express himself, the GP can make maximum use of patients' ability for problem formulation and solution. METHODS: We describe a model, for which the mnemonic, P-R-A-C-T-I-C-A-L, will help the practitioner to remember its nine steps. The model uses a chronological succession of strategies during the consultation that balances the voices of medicine and the lifeworld. In overview, the GP takes the patient, step by step, first through an exploration and clarification of his views of the illness, then expands the problem by further examination (e.g. the physical examination), a negotiation about the final model of the illness that includes both diagnosis and management, a discussion of the treatment plan, and finally a moment of reflection to prepare for the next visit.

Abbreviations as Topic↗
PubMed1997

Telephone consultations at the emergency service, Copenhagen County: analysis of doctor-patient communication patterns.

BACKGROUND: Experience from 10 telephone consultation courses in 1995, arranged for the emergency service in Copenhagen County, has demonstrated that this type of communication requires specific skills on the doctor's part, especially because the doctor cannot see the patient, patients are frequently in some sort of 'crisis' and, on the basis of limited information, the doctor in charge has to arrive at a prompt diagnosis in order to advise or refer the patient. METHODS: Using video-supervised role-play we compiled and organized the experience of 152 doctors. During the courses we developed principles to help doctors to optimize the information output and reliability of their telephone consultations. The doctors playing their 'patients" role had the opportunity to experience the situation from the patient's point of view and were later able to give the 'doctor' valuable feed-back. RESULTS AND CONCLUSIONS: This 'experimental consultation procedure' constitutes a new research method, at the interface between educational and traditional scientific research. The process in question is a feed-back one, in which findings can be applied and tested instantly, or with little delay, to produce new results. These can be put to use in practical clinical work and tested in new 'laboratory experiments'.

Communication↗
PubMed1995

[Attitude of Danish patients and physicians to information on cancer. A questionnaire study].

This survey reports the attitude towards information of cancer patients as regards diagnosis and prognosis among gastroenterologists and patients (not suffering from cancer). The questions were based on a case history (a patient with colonic cancer). Most doctors informed their patients openly, and most patients expected that. Younger doctors in particular were more restrictive than patients as regards information of the spouse.

Adult↗
PubMed1990

HIV infections and AIDS in Danish general practice--the role of the GP in AIDS prevention.

The occurrence and geographical distribution of HIV infections and AIDS (HIV/AIDS) in Danish general practice were examined in a questionnaire study sent to a 10% random sample of the GPs. Response rate was 92%. In 1988, a total of 2969 patients were tested, median 10 patients per GP. GPs had 148 HIV-positive patients (66 in Greater Copenhagen) and 60 AIDS patients (27 in Greater Copenhagen). In Greater Copenhagen 37% of the GPs had neither HIV nor AIDS patients, vs. 71% in the rest of the country. Instruction in infection prophylaxis was usually initiated by the GPs, while HIV testing was mainly on the patient's initiative. 52% of GPs indicated a change in their routine, particularly with respect to sterilization of instruments and avoidance of direct contact with blood. An extrapolation of the results of this study indicates that about 1,500 of the estimated 2,000 HIV positive patients in Denmark are known by general practitioners.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Integrated health work with 'the new family'.

In this Copenhagen practice couples receive antenatal and postnatal care in group sessions. The health care professionals believe they provide a better service. Parents learn from shared experiences and benefit from the social network that is established.

Child, Preschool↗
PubMed1989

Medical students experience early patient contact in general practice. A description and evaluation of a new course in the medical curriculum.

In the first year of the medical curriculum at the University of Copenhagen, a new discipline has been introduced, in which general practice has the key position in providing experiences of early patient contact to the students. The course consists of three principal elements: student-patient contacts in the patient's home; lessons with the general practitioner; and lessons at the Institute of General Practice. The compulsory course is completed by a student's report, and the first course has been evaluated by qualitative analysis of these reports and by questionnaires to the students and GPs. The results indicate that it is possible to provide considerable improvement of the medical education as regards communication skills and understanding of the patients' perceptions, by letting the student establish contact with a patient in the very beginning of the curriculum. General practice provides an appropriate setting for this education for both teachers and patients.

Curriculum↗
PubMed1988

Ultrastructure and histochemistry of the vas deferens of the salamander Rhyacotriton olympicus: adaptations for sperm storage.

The vas deferens of the salamander Rhyacotriton olympicus is composed of (1) a peritoneal epithelium, (2) connective tissue with fibroblasts, melanophores, circular smooth muscle, capillaries, and unmyelinated nerves within a collagenous matrix, and (3) an inner layer of cuboidal epithelium partially covered by ciliated squamous cells at the lumen. The lumen and apical cytoplasm of both epithelial cell types contain strongly PAS-positive granules. The cuboidal cells contained numerous swollen rough endoplasmic reticulum cisternae, mitochondria, and apical dense granules suggesting a high degree of secretory activity possibly involved in sperm maintenance. Fewer mitochondria, rough endoplasmic reticula, and granules in squamous cells suggest less secretory activity. Squamous cells may protect the cuboidal cells from possible abrasion by sperm masses and/or their cilia may aid in distributing secretory products in the lumen.

Animals↗