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Introduction: In health education, group work is essential to prepare students for working in health care and medical teams. Following the widespread adoption of online teaching, group work increasingly takes place in online environments. Although successful group work can provide good learning outcomes, it is unclear what facilitates or hinders online group work in health science education, and to what extent this topic has been addressed. Thus, this scoping review aimed to identify the facilitators and barriers to online group work in higher health education, provide an overview of the scientific literature related to the topic, and identify knowledge gaps in the research., Methods: This scoping review was guided by the methodological framework described by Arksey and O'Malley, and reporting is in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Review (PRISMA-ScR). Eight online databases were searched for scientific articles published between 2012 and 2022. At least two researchers independently screened records and full-text articles and charted data including article characteristics and key information related to the research question. Findings were categorized and summarized based on the Community of Inquiry Framework., Results: After screening 3671 records and 466 full-text articles, 39 articles met the inclusion criteria. The review revealed smaller group size, consistency in group composition and joint responsibility to be facilitators. Challenges with group communication, scheduling synchronous meetings and technical issues were identified as barriers. Our findings supported the importance of all three elements of the Community of Inquiry Framework: social, cognitive, and teaching presence., Conclusion: This review provides an overview of facilitators and barriers to online group work in health science education. However, there is a need for further investigation of these factors and studies addressing this topic from the teachers' perspective.

Purpose: The aim of this article was to investigate whether Schirmer strips gathered during clinical dry eye examinations can be prepared for omics analyses in a standardized way, to adjust for variations in tear volume and enable two separate omics analyses from the same sample. In addition, the intention was to investigate whether fluorescein dye instillation in the eyes gave bias effects on metabolomic analysis., Methods: Twelve samples from six individuals, with normal or reduced tear production, were collected. Half of the samples were harvested after instillation of fluorescein in the eye. Each strip was divided in half along the length and prepared with a new method for extracting tear content from the Schirmer strip. The new method was established to compensate for different dilutions of metabolites in varying Schirmer strip wetting levels when using identical extraction volume for all samples. Metabolomic data were compared in samples with and without fluorescein dye and Schirmer strips ranging from 1 to 35 mm wetting levels using a global LC-MS method., Results: All samples were successfully analyzed with an average of ∼350 relevant features detected per sample after using both positive and negative electrospray ionization mode, despite low tear volumes in some samples and that only one half of the Schirmer strips were used. Principal component analysis plots and heatmaps revealed no bias effects of fluorescein dye presence or different Schirmer strip values when using the proposed method., Conclusion: A high number of relevant metabolomic features can be extracted from longitudinally cut halves of Schirmer strips, which may enable analyses with more than one omics modality from the same sample. With the pre-analytical method described, Schirmer strips can be used for metabolomic analyses even in cases of very low or high tear volume with or without fluorescence.

Purpose: To compare the effect of treatment with preservative-free dexamethasone, NSAIDs and trehalose/hyaluronic acid eye drops with the preservative benzalkonium chloride containing dexamethasone and NSAIDs after cataract surgery in dry versus non-dry eyes., Patients and Methods: In this prospective randomized intervention study, dry eye tests were performed before and 6 weeks after cataract surgery. Patients were considered as having dry eye, SDE (sign of dry eye), if at least one of the following dry eye tests were abnormal; corneal fluorescein staining (CFS), non-invasive keratograph breakup time (NIKBUT) or tear osmolarity. Patients with SDE were randomly assigned to one of two groups. Group 1 patients were treated with dexamethasone and bromfenac eye drops with the preservative benzalkonium chloride (BAC). Group 2 patients were treated with preservative-free dexamethasone and preservative-free diclofenac, as well as a preservative-free lubricant with trehalose and hyaluronic acid both before and after surgery. Patients with normal tear film status acted as the control group (group 3) and received same treatment as group 1., Results: A total of 215 patients were enrolled six weeks after surgery, the number of patients with SDE decreased significantly in groups 1 and 2 (p <0.001). Subjective symptoms and objective measures including osmolarity, NIKBUT, CFS, and tear film thickness (TFT) improved after surgery, tear production remained unchanged, while corneal sensitivity and meibomian gland dysfunction (MGD) parameters worsened. In the control group with normal tear-film status, SDE increased significantly after the surgery (p <0.001). There were no statistically significant differences in tear film parameters between the three groups after surgery., Conclusion: After cataract surgery, patients with mild to moderate dry eyes may experience improved tear film status and reduced symptoms. However, we found no additional beneficial effect on dry eye parameters with treatment with preservative-free dexamethasone, NSAIDs, and lubricants compared to preservative-containing eye drops., Competing Interests: Richard (Rick) Potvin reports consulting fees from Alcon and Hoya. Dr Tor Utheim reports being one of around 20 owners of the Norwegian Dry Eye Clinic, during the conduct of the study. The authors report no other conflicts of interest in this work., (© 2024 Jensen et al.)

Competing Interests: The authors report no conflicts of interest in this communication.

Purpose: To evaluate the agreement of refractive predictability of a swept-source optical coherence tomography (SS-OCT) biometer, which uses segmental AL calculation, with another SS-OCT biometer, and an optical low coherence reflectometry (OLCR) biometer. The secondary objective was to describe the refractive outcomes, visual acuities, and the agreement of different preoperative biometric parameters., Patients and Methods: The study was a retrospective one-arm study of refractive and visual outcomes after successful cataract surgery. Preoperative biometric data were collected with two different SS-OCT device (Argos, Alcon Laboratories and Anterion, Heidelberg Engineering) and an OLCR device (Lenstar 900, Haag-Streit). The Barrett Universal II formula was used to calculate IOL power for all three devices. Follow-up examination was 1-2 months after surgery. The main outcome measure, refractive prediction error (RPE), was calculated as the achieved postoperative refraction minus the predicted refraction for each device. Absolute error (AE) was calculated by reducing the mean error to zero., Results: The study included 129 eyes of 129 patients. The mean RPE was 0.06, -0.14 and 0.17 D for the Argos, Anterion and Lenstar, respectively ( p < 0.01). The Argos also had the lowest absolute RPE, while the Lenstar had the lowest median AE, but this was not statistically significant ( p > 0.2). The percentages of eyes with RPE within ±0.5 was 76%, 71%, and 78% for the Argos, Anterion, and Lenstar, respectively. The percentages of eyes with AE within 0.5 D was 79%, 84%, and 82% for the Argos, Anterion and Lenstar, respectively. None of these percentages were statistically significantly different ( p > 0.2)., Conclusion: All three biometers showed good refractive predictability with no statistically significant differences in AE or percentages of eyes within ± 0.5 D of RPE or AE. The lowest arithmetic RPE was found with the Argos biometer., Competing Interests: Dr. Gundersen is a consultant to Alcon, Staar, Santen, Centricity, and Glaukos. Mr Bjørn Gjerdrum reports grants from Alcon, during the conduct of the study. This study was supported by an investigator-initiated study grant from Alcon, Fort Worth, TX (IIT #68660849). The authors report no other conflicts of interest in this work., (© 2023 Gjerdrum et al.)

Purpose: To determine the prevalence of dry eye disease (DED) in patients scheduled for cataract surgery in a Norwegian eye clinic., Patients and Methods: 218 patients scheduled for cataract surgery were examined for DED in one randomly selected eye and questioned regarding symptoms and risk factors. Patients were diagnosed with DED if they fulfilled the DEWS II criteria with symptom score >12/100 with Ocular Surface Disease Index (OSDI) questionnaire, and the presence of any of the three signs: tear osmolarity >307 mOsm/L in either eye or a difference in osmolarity between the two eyes of >8 mOsm/L, corneal fluorescein staining (CSF) ≥ grade 2 and non-invasive tear film breakup time (NIKBUT) of <10 seconds. Additional tests were the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, tear meniscus height (TMH), Schirmer 1, tear film thickness (TFT), corneal sensitivity and meibography (meiboscore). Dry eye test outcomes were correlated with risk factors for DED., Results: The prevalence of DED was 55.5% according to the DEWS II criteria. The abnormal osmolarity percentage was 66.5, while 29.8% had shortened NIKBUT and 19.7% exhibited CFS ≥2. 57% had Schirmer 1 ≤ 10 mm/5 min, and 81.1% had a meiboscore of ≥1. 71.2% of subjects scored positive for DED symptoms using the OSDI questionnaire and 69.3% using SPEED. Logistic regression analysis showed that higher age correlated with a lower OSDI symptom score, reduced corneal sensitivity and increased meibomian gland atrophy. Female sex was associated with higher odds of having DED, abnormal NIKBUT and abnormal CFS. Ocular tests for DED did not correlate with OSDI symptom scores when assessed with Spearman`s rank analysis., Conclusion: The prevalence of DED in an elderly Norwegian population scheduled for cataract surgery is high and associated with female sex. There was a lack of correlation between signs and symptoms of DED., Competing Interests: Dr Per Graae Jensen reports grants from The Research Council of Norway, during the conduct of the study. Dr Morten Gundersen reports grants from Norwegian research council, during the conduct of the study. Dr Rick Potvin reports personal fees from Alcon, personal fees from Carl Zeiss Meditec, outside the submitted work. Dr Øygunn A Utheim reports grants from The Research Council of Norway, during the conduct of the study; received artificial tear fluid from Thea Pharma, outside the submitted work. The authors report no other conflicts of interest in this work., (© 2023 Graae Jensen et al.)

Purpose: The purpose of this study was to evaluate the diagnostic value of inter-eye osmolarity differences in relation to dry eye symptoms and other non-osmolar signs of dry eye disease., Patients and Methods: One hundred ninety one participants who attended a larger interventional study of dry eye disease prior to and after cataract surgery were analyzed for dry eye disease (DED). Dry eye diagnostics were performed for all subjects according to the DEWS II criteria: tear osmolarity was collected from both eyes with the TearLab system, non-invasive Tear film break up time (NIKBUT) was obtained on the test eye with Keratograph and ocular surface staining (OSS) was evaluated using the Oxford schema. The Ocular Surface Disease Index (OSDI) questionnaire was used to assess symptoms. Inter-eye osmolarity greater than 8, which is considered as a sign of DED according to the TearLab user manual, was evaluated and compared with other non-osmolar signs of DED., Results: The 191 subjects were divided into three groups according to osmolarity measurements. Sixty-five subjects had normal osmolarity (below 308 mOsmol/L in both eyes and less than 9 mOsmol/L difference between the eyes), 107 had high osmolarity (308 mOsmol/L or higher in one of the eyes) and 19 had an inter-eye difference >8 mOsmol/L or higher, with neither eye having osmolarity higher than 307 mOsmol/L. Signs and symptoms in this last group were not correlated with the high osmolarity group or the normal group, though they appeared more similar to the normal group., Conclusion: The diagnostic value of inter-eye osmolarity difference in predicting symptoms or other non-osmolar signs of dry eyes appears weak. Our study suggests that the criterion of an inter-eye difference of 8 mOsmol/L is not a useful cut-off for diagnosing dry eyes based on osmolarity., Competing Interests: Mr Per Graae Jensen reports receiving 200 bottles of Thealoz duo for use of study purposes from Thea laboratories, grants from Norwegian council of Research, during the conduct of the study. Dr Morten Gundersen reports grants from Forskningsrådet Norge, and 200 samples of Thealoz-Duo (lubricant eye drops) were donated from Thea laboratories, during the conduct of the study. Dr Øygunn Utheim reports grants from the Research Council of Norway, during the conduct of the study and non-financial support from Thea Pharma, outside the submitted work. Dr Rick Potvin reports personal fees from Alcon, personal fees from Carl Zeiss Meditec, outside the submitted work. The authors report no other conflicts of interest in this work., (© 2023 Nilsen et al.)

Background: The long-term outcomes of Ulcerative colitis (UC) after discontinuation of biological therapy are largely unknown. There is also a lack of accurate and validated markers that can predict outcome after withdrawal accurately. The aims of this study were to describe the long-term outcomes in UC patients following cessation of anti-TNF therapy and explore potential biomarkers as an approach towards precision medicine., Methods: Seventy-five patients with moderate to severe UC treated to remission with anti-tumor necrosis factor (TNF) were included in the study. This is a follow-up of previously reported UC outcomes. The patients were categorized as either "Remission" or "Relapse". The "Relapse" group was divided into subgroups determined by the highest treatment level needed to obtain remission the last 3 years of observation: non-biological therapy, biological therapy or colectomy. Remission were divided in long term remission (LTR), those using immunomodulating drugs (LTR + imids) and those using only 5-amino-salicylate (5-ASA) treatment (LTR) for the past 3 years. Analyses of mucosal gene expression by real-time PCR were performed., Results: The median (IQR) observation time of all patients included was 121 (111-137) months. Of the 75 patients, 46 (61%) did not receive biological therapy, including 23 (31%) in LTR ± imids. Of these 23 patients, 16 (21%) were defined as LTR with a median observation time of (IQR) 95 (77-113) months. In total 14 patients (19%) underwent colectomy during the 10 years after first remission. Mucosal TNF copies/µg mRNA < 10 000 at anti-TNF discontinuation predicted long-term remission, biological free remission and lower risk of colectomy with a HR 0.36 (0.14-0.92) for long-term remission, HR 0.17 (0.04-0.78) for biological free remission and HR 0.12 (0.01-0.91) for colectomy. IL1RL1 was normalized in LTR phenotype and higher in relapsing UC., Conclusion: In this 10-year follow-up of UC of patients with moderate to severe disease, 61% of patients experience an altered phenotype to a milder disease course without need of biological therapy. Twenty-one percent of the patients were LTR without any medication except of 5-ASA. Mucosal TNF gene expression and IL1RL1- transcripts may be of clinical utility for long term prognosis in development of precision medicine in UC., (© 2022. The Author(s).)

In November 2018, the Woolsey Fire burned north of Los Angeles, CA, USA, potentially remobilizing radioactive contaminants at the former Santa Susana Field Laboratory, a shuttered nuclear research facility contaminated by chemical and radiochemical releases. Wildfire in radiologically contaminated zones is a global concern; contaminated areas around Chernobyl, Fukushima, Los Alamos, and the Nevada Nuclear Test Site have all experienced wildfires. Three weeks after the Woolsey Fire was controlled, sampling of dusts, ashes, and surface soils (n = 360) began and were analyzed by alpha- and beta-radiation counting. Samples were collected up to a 16 km radius from the perimeter of the laboratory. Controls and samples with activities 1σ greater than background were also examined by alpha and/or gamma spectroscopy or Scanning Electron Microscopy with Energy Dispersive X-ray analysis. Of the 360 samples collected, 97% showed activities at or close to site-specific background levels. However, offsite samples collected in publicly-accessible areas nearest to the SSFL site perimeter had the highest alpha-emitting radionuclides radium, thorium, and uranium activities, indicating site-related radioactive material has escaped the confines of the laboratory. In two geographically-separated locations, one as far away as 15 km, radioactive microparticles containing percent-concentrations of thorium were detected in ashes and dusts that were likely related to deposition from the Woolsey fire. These offsite radioactive microparticles were colocated with alpha and beta activity maxima. Data did not support a finding of widespread deposition of radioactive particles. However, two radioactive deposition hotspots and significant offsite contamination were detected near the site perimeter., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Little is known about the burden of atopic dermatitis (AD) encountered in US primary care practices and the frequency and type of skin care practices routinely used in children., Objective: To estimate the prevalence of AD in children 0 to 5 years attending primary care practices in the United States and to describe routine skin care practices used in this population., Design: A cross-sectional survey study of a convenience sample of children under the age of 5 attending primary care practices for any reason., Setting: Ten primary care practices in 5 US states., Results: Among 652 children attending primary care practices, the estimated prevalence of ever having AD was 24% (95% CI, 21-28) ranging from 15% among those under the age of 1 to 38% among those aged 4 to 5 years. The prevalence of comorbid asthma was higher among AD participants compared to those with no AD, namely, 12% and 4%, respectively ( P < .001). Moisturizers with high water:oil ratios were most commonly used (ie, lotions) in the non-AD population, whereas moisturizers with low water:oil content (ie, ointments) were most common when AD was present., Conclusions: Our study found a large burden of AD in the primary care practice setting in the US. The majority of households reported skin care practices that may be detrimental to the skin barrier, such as frequent bathing and the routine use of moisturizers with high water: oil ratios. Clinical trials are needed to identify which skin care practices are optimal for reducing the significant burden of AD in the community., Competing Interests: Conflict of interest: none declared., (© Copyright 2019 by the American Board of Family Medicine.)

Background: We aimed to evaluate the clinical usefulness of qSOFA as a risk stratification tool for patients admitted with infection compared to traditional SIRS criteria or our triage system; the Rapid Emergency Triage and Treatment System (RETTS)., Methods: The study was an observational cohort study performed at one Emergency Department (ED) in an urban university teaching hospital in Norway, with approximately 20,000 visits per year. All patients >16 years presenting with symptoms or clinical signs suggesting an infection (n = 1535) were prospectively included in the study from January 1 to December 31, 2012. At arrival in the ED, vital signs were recorded and all patients were triaged according to RETTS vital signs, presenting infection, and sepsis symptoms. These admission data were also used to calculate qSOFA and SIRS. Treatment outcome was later retrieved from the patients' electronic records (EPR) and mortality data from the Norwegian population registry., Results: Of the 1535 admitted patients, 108 (7.0%) fulfilled the Sepsis2 criteria for severe sepsis. The qSOFA score ≥2 identified only 33 (sensitivity 0.32, specificity 0.98) of the patients with severe sepsis, whilst the RETTS-alert ≥ orange identified 92 patients (sensitivity 0.85, specificity 0.55). Twenty-six patients died within 7 days of admission; four (15.4%) of them had a qSOFA ≥2, and 16 (61.5%) had RETTS ≥ orange alert. Of the 68 patients that died within 30 days, only eight (11.9%) scored ≥2 on the qSOFA, and 45 (66.1%) had a RETTS ≥ orange alert., Discussion: In order to achieve timely treatment for sepsis, a sensitive screening tool is more important than a specific one. Our study is the fourth study were qSOFA finds few of the sepsis cases in prehospital or at arrival to the ED. We add information on the RETTS triage system, the two highest acuity levels together had a high sensitivity (85%) for identifying sepsis at arrival to the ED - and thus, RETTS should not be replaced by qSOFA as a screening and trigger tool for sepsis at arrival., Conclusion: In this observational cohort study, qSOFA failed to identify two thirds of the patients admitted to an ED with severe sepsis. Further, qSOFA failed to be a risk stratification tool as the sensitivity to predict 7-day and 30-day mortality was low. The sensitivity was poorer than the other warning scores already in use at the study site, RETTS-triage and the SIRS criteria.

The objective was to use carbon nanotubes (CNT) coupled with near-infrared radiation (NIR) to induce hyperthermia as a novel non-ionizing radiation treatment for primary brain tumors, glioblastoma multiforme (GBM). In this study, we report the therapeutic potential of hyperthermia-induced thermal ablation using the sequential administration of carbon nanotubes (CNT) and NIR. In vitro studies were performed using glioma tumor cell lines (U251, U87, LN229, T98G). Glioma cells were incubated with CNTs for 24 h followed by exposure to NIR for 10 min. Glioma cells preferentially internalized CNTs, which upon NIR exposure, generated heat, causing necrotic cell death. There were minimal effects to normal cells, which correlate to their minimal uptake of CNTs. Furthermore, this protocol caused cell death to glioma cancer stem cells, and drug-resistant as well as drug-sensitive glioma cells. This sequential hyperthermia therapy was effective in vivo in the rodent tumor model resulting in tumor shrinkage and no recurrence after only one treatment. In conclusion, this sequence of selective CNT administration followed by NIR activation provides a new approach to the treatment of glioma, particularly drug-resistant gliomas.

Pulsed electric fields with nanosecond duration and high amplitude have effects on biological subjects and bring new venue in disease diagnosis and therapy. To address this respect, we investigated the responses of paired tumor and normal human skin cells - a basal cell carcinoma (BCC) cell line, and its sister normal cell line (TE) - to nanosecond, megavolt-per-meter pulses. When BCC (TE 354.T) and TE (TE 353.SK) cells, cultured under standard conditions, were exposed to 30 ns, 3 MV/m, 50 Hz pulses and tested for membrane permeabilization, viability, morphology, and caspase activation, we found that nanoelectropulse exposure: 1) increased cell membrane permeability in both cell lines but to a greater extent in BCC cells than in normal cells; 2) decreased cell viabilities with BCC cells affected more than normal cells; 3) induced morphological changes in both cell lines including condensed and fragmented chromatin with enlarged nuclei; 4) induced about twice as much caspase activation in BCC cells compared to normal cells. We concluded that in paired tumor and normal skin cell lines, the response of the tumor cells to nanoelectropulse exposure is stronger than the response of normal cells, indicating the potential for selectivity in therapeutic applications.

Mitochondrial dysfunction is intimately involved in cardiovascular diseases. Mitochondrial membrane potential (DeltaPsi(m)) is coupled with oxidative phosphorylation to drive ATP synthesis. In this study, we examined the effect of physiological pulsatile shear stress (PSS) on DeltaPsi(m) and the role of Mn-SOD expression on DeltaPsi(m). Confluent human aortic endothelial cells (HAEC) were exposed to PSS, and DeltaPsi(m) was monitored using tetramethylrhodamine methyl ester (TMRM(+)), a mitochondrial membrane potential probe. PSS significantly increased DeltaPsi(m) and the change in DeltaPsi(m) was a dynamic process. DeltaPsi(m) returned to baseline level after PSS for 2h followed by static state for 4h. Mitochondrial Mn-SOD expression and activities were also significantly up-regulated in response to PSS. Silencing Mn-SOD attenuated PSS-mediated DeltaPsi(m) increase while adding Mn-SOD mimetic, MnTMPyP, increased DeltaPsi(m) to the similar extent as induced by PSS. Our findings suggest that PSS-increased mitochondrial DeltaPsi(m), in part, via Mn-SOD up-regulation.

To add to the understanding of the properties of functionalized carbon nanotubes in biological applications, we report a monotonic pH sensitivity of the intracellular fluorescence emission of single-walled carbon nanotube-fluorescein carbazide (SWCNT-FC) conjugates in human ovarian cancer cells. Light-stimulated intracellular hydrolysis of the amide linkage and localized intracellular pH changes are proposed as mechanisms. SWCNT-FC conjugates may serve as intracellular pH sensors.

This paper describes the design, fabrication, packaging and testing of a microlens integrated in a multi-layered MEMS microspectrometer. The microlens was fabricated using modified PDMS molding to form a suspended lens diaphragm. Gaussian beam propagation model was used to measure the focal length and quantify M(2) value of the microlens. A tunable calibration source was set up to measure the response of the packaged device. Dual wavelength separation by the packaged device was demonstrated by CCD imaging and beam profiling of the spectroscopic output. We demonstrated specific techniques to measure critical parameters of microoptics systems for future optimization of spectroscopic devices.

We report the design, integration, and validation of a fluorescence microscopy system for imaging of electroperturbation--the effects of nanosecond, megavolt-per-meter pulsed electric fields on biological cells and tissues. Such effects have potential applications in cancer therapy, gene regulation, and biophysical research by noninvasively disrupting intracellular compartments and inducing apoptosis in malignant cells. As the primary observing platform, an epifluorescence microscope integrating a nanosecond high-voltage pulser and a micrometer electrode chamber enable in situ imaging of the intracellular processes triggered by high electric fields. Using specific fluorescence molecular probes, the dynamic biological responses of Jurkat T lymphocytes to nanosecond electric pulses (nanoelectropulses) are studied with this system, including calcium bursts, the polarized translocation of phosphatidylserine (PS), and nuclear enlargement and chromatin/DNA structural changes.

The high-resolution carbon 1s photoelectron spectrum of trans-1,3-pentadiene has been resolved into contributions from the five inequivalent carbon atoms, and carbon 1s ionization energies have been assigned to each of these atoms. Spectra have also been measured for propene and 1,3-butadiene at better resolution than has previously been available. The ionization energies for the sp2 carbons are found to correlate well with activation energies for electrophilic addition and with proton affinities. Comparing the results for 1,3-pentadiene with those for ethene, propene, and 1,3-butadiene as well as with results of theoretical calculations makes it is possible to assess the effect of the terminal methyl group in 1,3-pentadiene. As in propene, the methyl group contributes electrons to the beta carbon through the pi system. In addition, there is a significant (though smaller) contribution from the methyl group to the terminal (delta) CH2 carbon, also through the pi system. Most of the effect of the methyl group is present in the ground-state molecule. There are only relatively small contributions from the methyl group to the ionization energies from redistribution of charge in the pi system in response to the removal of a core electron. In addition to these specific effects, there is an overall decrease in average ionization energy as the size of the molecule increases as well as effects that are specific to the conjugated systems in 1,3-butadiene and 1,3-pentadiene. The results provide insight into the reactivity and regioselectivity of conjugated dienes.

Objectives: To discuss the advantages and disadvantages of an interfaced approach to clinical information systems architecture., Methods: After many years of internally building almost all components of a hospital clinical information system (HELP) at Intermountain Health Care, we changed our architectural approach as we chose to encompass ambulatory as well as acute care. We now seek to interface applications from a variety of sources (including some that we build ourselves) to a clinical data repository that contains a longitudinal electronic patient record., Results: We have a total of 820 instances of interfaces to 51 different applications. We process nearly 2 million transactions per day via our interface engine and feel that the reliability of the approach is acceptable. Interface costs constitute about four percent of our total information systems budget. The clinical database currently contains records for 1.45 m patients and the response time for a query is 0.19 sec., Discussion: Based upon our experience with both integrated (monolithic) and interfaced approaches, we conclude that for those with the expertise and resources to do so, the interfaced approach offers an attractive alternative to systems provided by a single vendor. We expect the advantages of this approach to increase as the costs of interfaces are reduced in the future as standards for vocabulary and messaging become increasingly mature and functional.

Free-text or natural language documents make up an increasing part of the computerized medical record. While they do provide accessible clinical information to health care personnel, they fail to support processes that require clinical data coded according to a shared lexicon and data structure. We have developed a natural language parser that converts free-text admitting diagnoses into a coded form. This application has proven acceptably accurate in the experimental laboratory to warrant a test in the target clinical environment. Here we describe an approach to moving this research application into a production environment where it can contribute to the efforts of the Health Information Services Department. This transition is essential if the products of natural language understanding research are to contribute to patient care in a routine and sustainable way.

Hospital information systems designed to support the needs of health care professionals include patient data entered using both freetext and precoded storage schemes. A major disadvantage of freetext storage schemes is that data captured in this format can only be presented as is to the user for review tasks. In the view of many health care scientists, natural language understanding systems capable of identifying, extracting, and encoding information contained in freetext data may provide the necessary tools to overcome this weakness. This paper describes the development and evaluation of a such a system designed to encode freetext admission diagnoses. This system combines both semantic and syntactic linguistic analysis techniques. Evaluation results demonstrate the overall performance of this system to be reasonable, accurately encoding approximately 76% of admission diagnoses. Inefficiencies are primarily due to the inability of this system to generate encodings in roughly 15% of test cases. When encodings are produced, however, accuracy equals that of the current manual coding method. With further modification, this application can partially automate the coding process.

In this paper several optical processes that may be used to affect gas-phase switch performance and operation are discussed, and approaches using a laser to increase recovery rates of switches are presented. In the latter the laser is used during the recovery phase rather than the conductive or closure phase. This paper suggests that it should be possible to use a low-power laser (e.g., one that is technologically feasible to use as part of a switch) to assist in opening the switch by quenching excited atomic and/or molecular species. The application of laser-induced energy extraction to gas-phase switches is also discussed.

Single longitudinal mode output of a pulsed TE CO(2) laser has been obtained using several different intracavity gas-phase absorbers. The method described is simple and inexpensive and appears to be extremely general.