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PubMed2026

Fedflow: cloud orchestration for federated learning with the FeatureCloud platform.

MOTIVATION: Federated learning (FL) enables collaborative model training on geographically distributed genomic and clinical datasets while complying with data privacy laws and regulatory constraints. FeatureCloud is an existing platform for FL that provides an accessible web-based interface and a large repository of implemented methods. However, due to its graphical interface, FeatureCloud requires manual interaction of all participants, limiting automation, iteration, and reproducibility. RESULTS: We introduce fedflow, a Python-based command-line tool for headless orchestration of FL tasks with FeatureCloud. This tool uses distributed computing resources such as virtual machines or cloud instances to automate such workflows. This allows for scalable federated computing either in local simulations or deployed in a trusted environment. Further, we demonstrate how fedflow can be used to integrate FeatureCloud in reproducible Snakemake workflows. For this, we reanalyse a metagenomic dataset with two federated algorithms and compare the results to the centralized approach with pooled data. Overall, fedflow enables automation of multi-client FL tasks, facilitates embedding of FeatureCloud in standard bioinformatics pipelines and thereby helps increase reproducibility. AVAILABILITY: Fedflow is open-source and available at https://github.com/W-L/fedflow.

Journal Article↗
PubMed1991

The epidemiology of cutaneous malignant melanoma: aetiology and European data.

Increases in cutaneous malignant melanoma (CMM) incidence and mortality rates have occurred in the last decades in virtually all white populations, more markedly in those which permanently (immigrants) or temporarily (tourists/vacationers) reside in very sunny areas distant from their original living environment. The strong relationship between sex and site of CMM in these upward trends (ie trunk in males, lower limbs and, more recently, trunk as well in females) points to intense intermittent ultraviolet light exposure as the cause of the CMM epidemic. In Europe the highest rates of melanoma are seen in Denmark, The Netherlands, the United Kingdom, Ireland and Germany, where many individuals have light complexion with tendency to burn. Increases of 2 to 7% per year in mortality rates appeared earlier in these countries, but were subsequently seen also in relatively low-risk areas such as southern European countries. The interpretation of data from case-control studies is, however, hampered by the difficulties in quantifying retrospectively CMM risk correlates (ie host factors, sun exposure, clothing habits, sunburns etc) in various periods during the life span.

Adult↗
PubMed2006

Translating person-centred care: a case study of preceptor nurses and their teaching practices in acute care areas.

AIMS AND OBJECTIVES: The research aims to explore how preceptors interpret, operationalize, document and teach person-centred care as they guide students within an acute surgical environment. BACKGROUND: Person-centred care is a term that is widely used in the nursing literature; however, its interpretation in nursing practice remains virtually unexplored. This is of great significance to nurses in general but to Irish nurses in particular on whom this study is focused. As preceptor nurses have been identified as key people in the education of clinical students, it was considered important to explore how clinical preceptors promote person-centred care to current undergraduate nursing students. DESIGN AND METHOD: Using a case study design and a qualitative approach, six preceptors were chosen to participate in this study. Data were collected by means of participant observation, review of nursing care records and semi-structured interviews. Data were analysed in two stages. The first stage involved the identification of themes. In the second stage data were analysed using a number of propositions to examine and explain what was gleaned from the data in the context of what was originally identified in the literature. RESULTS: Findings highlighted that preceptors had a limited conception of person-centred care. Measures of care reflected the medical model of nursing. Beyond that, preceptors expressed care in terms of good manners or respectful etiquette. Preceptors also had limited appreciation of what learning entails and were sceptical about classroom theory other than what they considered essential for safe practice. CONCLUSIONS: This study highlights that preceptors need both internal and external support to implement the changes advocated by the Commission in Nursing in 1998, the Nursing Education Forum in 2000, the Department of Health and Children in 2001 and An Bord Altranais in 2003. RELEVANCE TO CLINICAL PRACTICE: Person-centred care is a relatively new concept in nursing and recommended for practice. Preceptors need facilitation with its implementation. In an effort to promote changes in the delivery of health care, it is suggested that university-based lecturers empower students to practice evidence-based nursing as students and subsequently as qualified nurses.

Acute Disease↗
PubMed1992

Ion transport in parasitic protozoa.

Many parasitic protozoa go through complex life cycles in the course of which they adapt to widely different environments; ion transport processes are expected to play a role both in pathogenicity and in adaptation. So far, studies on ion transport have been virtually limited to Leishmania, Plasmodium and Entamoeba. The distribution of ion pumps in the former two organisms generally appears to conform to the picture established for other protozoa, i.e. a proton-motive P-ATPase in the plasma membrane provides the driving force for H(+)-coupled secondary-active transport, a proton-motive V-ATPase in the digestive vacuoles is responsible for vacuolar acidification, and an F-ATPase (ATP synthase) is found in the mitochondria. The situation in Entamoeba, an archaic organism that lacks mitochondria, could be different from that in the two other parasites in that a V-ATPase may be present and active both in the plasma membrane and in the membranes of the endocytic vesicles.

Animals↗
PubMed1998

Virtual medical trainer. Patient assessment and trauma care simulator.

The Virtual Medical Trainer (VMET) combines multimedia sound and graphics with physiological engines, medical-procedures databases, and 3-D patients to produce an interactive environment that can mimic the cognitive pre-hospital assessment and care demands of a real emergency. VMET uses a reconfigurable component software and training framework that allows a uniform user interface, ease of increasing training complexity, and expansion of the software components. VMET provides an opportunity to experience a range of trauma scenarios prior to the challenge of an actual trauma situation.

Algorithms↗
PubMed2000

Immersive virtual reality platform for medical training: a "killer-application".

The Medical Readiness Trainer (MRT) integrates fully immersive Virtual Reality (VR), highly advanced medical simulation technologies, and medical data to enable unprecedented medical education and training. The flexibility offered by the MRT environment serves as a practical teaching tool today and in the near future the will serve as an ideal vehicle for facilitating the transition to the next level of medical practice, i.e., telepresence and next generation Internet-based collaborative learning.

Computer Simulation↗
PubMed2004

The delivery simulator: a new application of medical VR.

This paper presents an elementary overview of the potential of Multimodal Virtual Reality (MVR) techniques in medical education, e.g. obstetrics. The study shows how to transfer the concept of MVR from a time-independent environment, e.g. the Munich Knee Joint Simulator, to a time-critical simulation environment as it can be found in flight simulators. The simulator consists of a haptic, a graphical and an acoustic user interface, which are connected to a biomechanical model for the birth process itself and a physiological model of both mother and child, in order to simulate, e.g. a cardiotocograph (CTG). The user can just watch an uncomplicated birth or is acting as the responsible obstetrician who has a variety of treatment options during the delivery with the most relevant medication or forceps/vacuum-extraction. During this practical training a MVR feedback system assists the trainee and exposes his errors and, thus, allows him to learn faster without endangering a real mother and her child. This concept allows for the first time to transfer stored haptic expert-knowledge to the trainee without a tool-based feedback approach.

Computer Simulation↗
PubMed2003

Implementation of a fast 16-Bit dynamic clamp using LabVIEW-RT.

The dynamic-clamp method provides a powerful electrophysiological tool for creating virtual ionic conductances in living cells and studying their influence on membrane potential. Here we describe G-clamp, a new way to implement a dynamic clamp using the real-time version of the Lab-VIEW programming environment together with a Windows host, an embedded microprocessor that runs a real-time operating system and a multifunction data-acquisition board. The software includes descriptions of a fast voltage-dependent sodium conductance, delayed rectifier, M-type and A-type potassium conductances, and a leak conductance. The system can also read synaptic conductance waveforms from preassembled data files. These virtual conductances can be reliably implemented at speeds < or =43 kHz while simultaneously saving two channels of data with 16-bit precision. G-clamp also includes utilities for measuring current-voltage relations, synaptic strength, and synaptic gain. Taking an approach built on a commercially available software/hardware platform has resulted in a system that is easy to assemble and upgrade. In addition, the graphical programming structure of LabVIEW should make it relatively easy for others to adapt G-clamp for new experimental applications.

Analog-Digital Conversion↗
PubMed1997

Evaluation of virtual source beam configurations for rapid tomographic reconstruction of gas and vapor concentrations in workplaces.

Beam path average data from an Open Path Fourier Transform Infrared (OP-FTIR) spectrometer can be used to reconstruct two-dimensional concentration maps of the gas and vapor contaminants in workplaces and the environment using computed tomographic (CT) techniques. However, a practical limitation arises because in the past, multiple-source and detector units were required to produce a sufficient number of intersecting beam paths in order to reconstruct concentration maps. Such a system can be applied to actual field monitoring situations only with great expense and difficulty. A single monostatic OP-FTIR system capable of rapid beam movement can eliminate this deficiency. Instead of many source and detector units, a virtual source arrangement has been proposed using a number of flat mirrors and retroreflectors to obtain intersecting folded beam paths. Three virtual source beam configurations generated for a single-beam steerable FTIR system were tested using 54 flat mirrors and four retroreflectors or 54 flat mirrors and 56 retroreflectors mounted along the perimeter walls of a typical 24- x 21-ft test room. The virtual source CT configurations were numerically evaluated using concentration maps created from tracer gas concentration distributions measured experimentally in a test chamber. Synthetic beam path integral data were calculated from the test maps and beam configurations. Computer simulations of different beam configurations were used to determine the effects of beam geometry. The effects of noise and peak reducing artifacts were evaluated. The performance of the tomographic reconstruction strategy was tested as a function of concentration and concentration gradients.

Air Pollution, Indoor↗
PubMed1976

Home humidifier thermophilic actinomycete isolates.

Twenty-seven thermophilic actinomycete isolates obtained from humidification systems or living-bedroom areas of individuals with suspected but unproved home environment-related respiratory disease were characterized morphologically and biochemically. All isolates were demonstrated to be members of the Thermoactinomyces genus. Two previously misidentified isolates were reclassified as a Thermoacetinomyces sp. Thus, all of our thermophilic actinomycete humidifier isolates studied to date have been identified as either Thermoactinomyces vulgaris or Thermoactinomyces sp. Large numbers of unidentified thermotolerant bacteria have also been isolated from virtually all residual humidifier water samples and their possible role in production of "humidifier-associated" respiratory disease is unknown.

Actinomycetales↗
PubMed1987

Influence of Soil and Nonsoil Environments on Nodulation by Rhizobium trifolii.

Indigenous serotypes 1-01 and 2-02 of Rhizobium trifolii occupied similar percentages (18 to 23%) of root nodules on soil-grown subclover (Trifolium subterraneum L.) and were virtually absent (4.5%) from nodules of soil-grown white clover (Trifolium repens L.). In contrast (with the exception of one dilution [10]), serotype 1-01 occupied a substantial portion of nodules (16 to 40%) on white clover seedlings grown on mineral salts agar and exposed to samples of the same soil in the form of a 10-fold dilution series (10 to 10). Under the latter conditions, occupancy of subclover nodules by 1-01 and of nodules of both plant species by 2-02 was consistent with the results obtained with soil-grown plants.

Journal Article↗
PubMed2004

The blue light-specific response of Vicia faba stomata acclimates to growth environment.

Stomata in epidermal strips from growth chamber-grown Vicia faba leaves opened less in response to white light than did stomata from greenhouse-grown leaves. Chlorophyll-mediated, red light-stimulated opening was similar in stomata from the two growth conditions, but stomata from the growth chamber environment had a severely reduced response to blue light. Transfer of plants between the two growth conditions resulted in an acclimation of the stomatal blue light response. Stomata lost blue light sensitivity within 1 d of transfer to growth chamber conditions and gained sensitivity to blue light over an 8 d period after transfer to a greenhouse. Short-term transfer experiments confirmed that the rapid loss of blue light sensitivity was an acclimation response, requiring between 12 and 20 h exposure to growth chamber conditions. The acclimation of the stomatal response to blue light was inversely related to a previously reported acclimation response in which stomata change between high CO2 sensitivity under growth chamber conditions and low CO2 sensitivity under greenhouse conditions. The time courses of the blue light and CO2 acclimation responses were virtually identical, suggesting the possibility of a common acclimation mechanism.

Acclimatization↗
PubMed1996

Social organization and aggression in a group of olfactory bulbectomized male mice.

Olfactory bulbectomized and control male CF-1 strain mice were housed in separate, large, seminatural environments over a 30-day observation period. Control mice engaged in vigorous fighting behavior before a dominant animal emerged. The alpha mouse established the floor area as its territory and vigorously attacked all other mice that ventured from the second tier of the enclosure to the floor. Lower ranking mice had numerous body scars, were much less aggressive, and engaged in a variety of nonaggressive social interactions. In contrast, bulbectomized mice did not fight and roamed freely through all areas of the environment. These mice largely ignored one another, engaged in little or no social behavior, and had no body scars. When two anosmic mice came into physical contact, they appeared startled and moved away from one another. These results, together with those of prior studies, indicate that olfaction plays a critical role in virtually all aspects of social behavior in male mice.

Aggression↗
PubMed2001

Neutron measurements onboard the space shuttle.

The radiation environment inside a shielded volume is highly complex, consisting of both charged and neutral particles. Since the inception of human space flights, the charged particle component has received virtually all of the attention. There is however, a significant production of secondary neutrons, particularly from the aluminum structure in low earth orbiting spacecrafts. The interactions of galactic cosmic rays (GCR), and solar energetic particles with the earth's atmosphere produce a non-isotropic distribution of albedo neutrons. Inside any reasonable habitable module, the average radiation quality factor of neutrons is about 4-5 times larger than the corresponding average quality factor of charged particles. The measurement of neutrons and their energy spectra is a difficult problem due the intense sources of charged particles. This paper reviews the results of Shuttle flight experiments (made during both solar maximum and solar minimum) to measure the contribution of neutrons to the dose equivalent, as well as theoretical calculations to estimate the appropriate range of neutron energies that contribute most to the dose equivalent.

Cosmic Radiation↗
PubMed1995

Vibrational Raman optical activity of alpha-lactalbumin: comparison with lysozyme, and evidence for native tertiary folds in molten globule states.

Proteins in aqueous solution are now accessible to Raman optical activity (ROA) measurements, which provide an incisive new probe of secondary and tertiary structure illustrated here by a study of bovine alpha-lactalbumin. The room-temperature ROA spectrum of native bovine alpha-lactalbumin is similar to that of native hen egg-white lysozyme except for features attributable to differences in the loop regions: in particular, a positive ROA band at approximately 1338 cm-1 assigned to conformationally homogeneous loop structure, possibly with local order corresponding to 3(10)-helix, has more than double the intensity in alpha-lactalbumin compared with lysozyme. This is consistent with the two proteins having similar secondary structure but different local details in the tertiary fold. ROA measurements on alpha-lactalbumin at pH 2.0 over a range of temperatures have provided a new perspective on the molten globule state. Thus at 35 degrees C ROA reveals the presence of some secondary structure but an almost complete loss of the tertiary loop structure; whereas at 2 degrees C the ROA spectrum is almost identical with that of the native protein, which is strong evidence that virtually all of the secondary structure and the tertiary backbone fold persist, albeit within a looser framework associated with increased solvent exposure and change of environment of many of the side-chains as evidenced by an increase in noise and bandwidth of some of the ROA signals together with aromatic fluorescence and near-UV circular dichroism signals characteristic of the molten globule state. Our sample of acid alpha-lactalbumin at 2 degrees C therefore appears to be an archetypal example of Ptitsyn's "native-like" molten globule, having a fixed native-like tertiary fold but with loss of tight packing of the side-chains; whereas at 35 degrees C it is a "disordered" molten globule. At 20 degrees C the acid molten globule appears to retain highly native-like secondary structure but with most of the tertiary fold already lost. A calcium-free sample of alpha-lactalbumin at neutral pH displayed a broad cooperative transition between native and molten globule states at approximately 15 degrees C, with the latter state showing similar but somewhat degraded tertiary loop ROA signatures to the native protein. In both the acid and apo molten globule states the ROA signatures of the secondary structure and the tertiary loops showed a gradual change with temperature.

Calcium↗