Home Laboratory Research Articles

New developments in crystallography: exploring its technology, methods and scope in the molecular biosciences.

Since the Protein Data Bank (PDB) was founded in 1971, there are now over 120,000 depositions, the majority of which are from X-ray crystallography and 90% of those made use of synchrotron beamlines. At the Cambridge Structure Database (CSD), founded in 1965, there are more than 800,000 ‘small molecule’ crystal structure depositions and a very large number of those are relevant in the biosciences as ligands or cofactors. The technology for crystal structure analysis is still developing rapidly both at synchrotrons and in home labs. Determination of the details of the hydrogen atoms in biological macromolecules is well served using neutrons as probe. Large multi-macromolecular complexes cause major challenges to crystallization; electrons as probes offer unique advantages here. Methods developments naturally accompany technology change, mainly incremental but some, such as the tuneability, intensity and collimation of synchrotron radiation, have effected radical changes in capability of biological crystallography. In the past few years, the X-ray laser has taken X-ray crystallography measurement times into the femtosecond range. In terms of applications many new discoveries have been made in the molecular biosciences. The scope of crystallographic techniques is indeed very wide. As examples, new insights into chemical catalysis of enzymes and relating ligand bound structures to thermodynamics have been gained but predictive power is seen as not yet achieved. Metal complexes are also an emerging theme for biomedicine applications. Our studies of coloration of live and cooked lobsters proved to be an unexpected favourite with the public and schoolchildren. More generally, public understanding of the biosciences and crystallography’s role within the field have been greatly enhanced by the United Nations International Year of Crystallography coordinated by the International Union of Crystallography. This topical review describes each of these areas along with illustrative results to document the scope of each methodology.

Determination of zip coefficients for residential loads

In this study, constant-impedance, constant-current and constant-power ZIP models have been analyzed for residental loads. Measurement based approach has been used to obtain ZIP models of selected loads. The measurement-based approach for load modeling is important because it reflects the real dynamics of the system and represents the load characteristics more accurately. The ZIP model is used to estimate the power drawn by the load depending on the voltage changes. Since the ZIP load model is a well-known model that provides power dependence in terms of the physical sense of voltage, studies are taking place in this area. In this study, the voltage and power values of selected residental loads at YTU Smart Home Laboratory are measured. Then, the ZIP coefficients have been calculated by using the least squares algorithm developed in MATLAB. The measured data is compared with the data from the obtained ZIP model for each appliance.

Comparison of home sleep apnea testing versus laboratory polysomnography for the diagnosis of obstructive sleep apnea in children

IntroductionObstructive sleep apnea (OSA) affects 1–5% of pediatric patients. Laboratory polysomnography is expensive, not always available, and is inconvenient for patients. Our study investigates the diagnostic ability of an unattended ambulatory monitor for the diagnosis of pediatric OSA. MethodsA prospective study was conducted in children, ages 2–17. Subjects completed in-lab polysomnography simultaneously with ambulatory monitoring. Caregivers attempted home studies on two subsequent nights to compare the home monitor and the laboratory polysomnogram (PSG). ResultsThirty-three subjects completed simultaneous laboratory polysomnogram with portable monitoring. Twenty patients completed home studies, with 16 completing 2 nights of monitoring. The measurement of AHI by the portable monitor was different than that obtained by the PSG with statistical significance for the comparisons of PSG vs. In-Lab (p = 0.0026), PSG vs. Home 1 (p = 0.033), and PSG vs. Home 2 (p = 0.033). The sensitivity of the portable monitor for diagnosing OSA was best for the In-lab use at 81%, but only 69% and 70% for the uses at home on the 2 nights respectively. Interestingly, the comparison of AHI and lowest oxygen saturation measurements from the home sleep test in children age 6 and older did not differ significantly from the PSG. ConclusionsThis pilot study demonstrated differences between home sleep testing and in-lab polysomnography for the diagnosis of pediatric sleep apnea. These differences were predominantly found to exist in younger children. Larger prospective studies are needed prior to widespread use, but home studies may alleviate issues of access to care and higher costs of laboratory polysomnography.

Easy yet powerful biological solution SAXS instrumentation for the home lab

Easy yet powerful biological solution SAXS instrumentation for the home lab

Safety and Efficacy of Warfarin Therapy in Kawasaki Disease

To describe the safety and efficacy of warfarin for patients with Kawasaki disease and giant coronary artery aneurysms (CAAs, ≥8 mm). Giant aneurysms are managed with combined anticoagulation and antiplatelet therapies, heightening risk of bleeding complications. We reviewed the time in therapeutic range; percentage of international normalization ratios (INRs) in range (%); bleeding events, clotting events; INRs ≥6; INRs ≥5 and <6; and INRs <1.5. In 9 patients (5 male), median age 14.4 years (range 7.1-22.8 years), INR testing was prescribed weekly to monthly and was done by home monitor (n = 5) or laboratory (n = 3) or combined (1). Median length of warfarin therapy was 7.2 years (2.3-13.3 years). Goal INR was 2.0-3.0 (n = 6) or 2.5-3.5 (n = 3), based on CAA size and history of CAA thrombosis. All patients were treated with aspirin; 1 was on dual antiplatelet therapy and warfarin. The median time in therapeutic range was 59% (37%-85%), and median percentage of INRs in range was 68% (52%-87%). INR >6 occurred in 3 patients (4 events); INRs ≥5 <6 in 7 patients (12 events); and INR <1.5 in 5 patients (28 events). The incidence of major bleeding events and clinically relevant nonmajor bleeding events were each 4.3 per 100 patient-years (95% CI 0.9-12.6). New asymptomatic coronary thrombosis was detected by imaging in 2 patients. Bleeding and clotting complications are common in patients with Kawasaki disease on warfarin and aspirin, with INRs in range only two-thirds of the time. Future studies should evaluate the use of direct oral anticoagulants in children as an alternative to warfarin.

Efficient collection and preparation of methane from low concentration waters for natural abundance radiocarbon analysis

AbstractFreshwater and marine environments constitute the largest global reservoirs of the greenhouse gas methane (CH4) and natural abundance radiocarbon measurements (14C‐CH4) can allow for high confidence interpretations about CH4 dynamics operating in these environments. Collecting sufficient amounts of CH4 sample for a standard, high precision 14C‐accelerator mass spectrometry (AMS) analysis (∼ 200 μg carbon (C)) was previously unfeasible when sampling from low CH4 concentration waters, such as much of the surface ocean (∼ 2 nM), which would require collecting the CH4 from 8500 L of seawater. The method described here involves pumping 20,000–40,000 L of seawater up from depth through a dissolved gas extraction system, which enables the collection of a sample composed of 100s of L of gas in less than 4 h on station. The large volume extracted gas sample is compressed into a 1.7 L cylinder for transport from the ship to the home laboratory. The home laboratory preparation of each sample to a CH4‐derived carbon dioxide aliquot for 14C‐AMS analysis is carried out in 3 h on a flow‐through vacuum line that simultaneously prepares aliquots for stable isotope analyses (δ13C‐CH4 and δ2H‐CH4). The total process blank of the method is small (5.0 μg CH4‐C) and composes 1.2% of the average collected and prepared sample (424 ± 163 μg, from a recent campaign; n = 16). The 14C‐CH4 blanks prepared on the vacuum line have acceptably low 14C content (0.23 ± 0.07 percent Modern Carbon (pMC); n = 7) relative to the 14C‐dead (0 pMC) CH4 from which they are prepared.

The Behavior of Liquid Alloys Visualized by X-Rays

Developments in synchrotron and home laboratory X-ray sources and fast low noise X-ray imaging detectors over the last 15-20 years has enabled real time X-radiography of alloy solidification from the melt. These investigations have been an important tool for in–situ investigations of dendrite-, eutectic and monotectic growth, dendrite fragmentation etc. At the same time, the techniques have allowed studies of phenomena in the melt such as convection, formation of solute boundary layers and minority phase droplet interactions. The article will review the X-radiography techniques and some of the results with emphasis on studies of phenomena in alloy melts.

Matthias Tamm

Angewandte Chemie International EditionVolume 56, Issue 4 p. 932-932 Author ProfileFree Access Matthias Tamm First published: 29 December 2016 https://doi.org/10.1002/anie.201611663AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract “My favorite painter is Edward Hopper. When I was eighteen I wanted to be a chemist. ...” This and more about Matthias Tamm can be found on page 932. Matthias Tamm The author presented on this page has published more than 10 articles in Angewandte Chemie in the last 10 years. His most recent article is published in this issue: “N-Heterocyclic Carbene Stabilized Boryl Radicals”: M. F. Silva Valverde, P. Schweyen, D. Gisinger, T. Bannenberg, M. Freytag, C. Kleeberg, M. Tamm, Angew. Chem. Int. Ed. 2017, 56, 1135; Angew. Chem. 2017, 129, 1155. The work of M. Tamm has been featured on the cover of Angewandte Chemie: “Heterolytic Dihydrogen Activation by a Frustrated Carbene–Borane Lewis Pair”: D. Holschumacher, T. Bannenberg, C. G. Hrib, P. G. Jones, M. Tamm, Angew. Chem. Int. Ed. 2008, 47, 7428; Angew. Chem. 2008, 120, 7538. Date of birth: February 12, 1967 Position: Professor of Inorganic and Analytical Chemistry, Technische Universität Braunschweig E-mail: m.tamm@tu-bs.de Homepage: https://www.tu-braunschweig.de/iaac/personal/tamm ORCID: 000-0002-5364-0357 Education: 1990 Diploma in chemistry, Technische Universität (TU) Berlin 1992 PhD with F. Ekkehardt Hahn, TU Berlin 1993–1994 Visiting research scientist with Anthony J. Arduengo III, DuPont Central Research and Development, Wilmington 1994–1999 Habilitation (mentor: F. Ekkehardt Hahn, University of Münster) Awards: 2000 Bennigsen-Foerder Prize, State of North Rhine-Westphalia; 2014 Honorary Doctorate, University Politehnica, Bucharest; 2016 Gheorghe Spacu Medal, Romanian Chemical Society Current research interests: Preparative organometallic chemistry; development of ancillary ligands for homogeneous catalysis; frustrated Lewis pairs; alkyne metathesis; cycloheptatrienyl complexes Hobbies: Sailing, running, swimming, skiing, hiking, reading My favorite painter is Edward Hopper. When I was eighteen I wanted to be a chemist. Young people should study chemistry because they will be able to change the world for the better. The most significant historic event of the past 100 years was for me, personally, the German reunification. The most important future applications of my research are efficient (and hopefully applicable) homogeneous catalytic processes. My first experiment was the preparation of “universal sulfate” in my home laboratory by dissolving nails, screws, and nuts in concentrated sulfuric acid. I advise my students to “Macht viel, dann geht auch viel” (borrowed from my academic grandfather, the late Herbert Schumann), loosely translated: Do many things (in the lab), then many things will work! My favorite band is Volbeat at present; the best bands of all (my) time are Queen and AC/DC. My favorite structure is that of the bis(cycloheptatrienyl)uranium anion, [(η7-C7H7)U]−, a sandwich complex with D7d symmetry. My favorite book is Business Class by Martin Suter together with all other titles in this series. My 5 top papers: References 1“Catalytic Metathesis of Conjugated Diynes”: S. Lysenko, J. Volbeda, P. G. Jones, M. Tamm, Angew. Chem. Int. Ed. 2012, 51, 6757; Angew. Chem. 2012, 124, 6861. (The discovery of a new reaction type.) 2“Efficient Metathesis of Terminal Alkynes”: B. Haberlag, M. Freytag, C. G. Daniliuc, P. G. Jones, M. Tamm, Angew. Chem. Int. Ed. 2012, 51, 13019; Angew. Chem. 2012, 124, 13195. (The title says it all!) 3“Phosphane-Functionalized Cycloheptatrienyl–Cyclopentadienyl Titanium Sandwich Complexes: Phosphorus Ligands with an Integrated Reducing Agent for Palladium(0) Catalyst Generation”: A. C. Tagne Kuate, S. Sameni, M. Freytag, P. G. Jones, M. Tamm, Angew. Chem. Int. Ed. 2013, 52, 8638; Angew. Chem. 2013, 125, 8800. (New competition for ferrocenyl and biaryl phosphanes.) 4“Iridium(I) Complexes with Anionic N-Heterocyclic Carbene Ligands as Catalysts for the Hydrogenation of Alkenes in Nonpolar Media”: E. L. Kolychev, S. Kronig, K. Brandhorst, M. Freytag, P. G. Jones, M. Tamm, J. Am. Chem. Soc. 2013, 135, 12448. (Very robust, widely applicable iridium catalysts.) 5“N-Heterocyclic Carbene–Phosphinidyne Transition Metal Complexes”: A. Doddi, D. Bockfeld, T. Bannenberg, P. G. Jones, M. Tamm, Angew. Chem. Int. Ed. 2014, 53, 13568; Angew. Chem. 2014, 126, 13786. (Our way into main-group-element chemistry.) Volume56, Issue4January 19, 2017Pages 932-932 ReferencesRelatedInformation

227 - Home INR Monitoring Versus Lab Monitoring in Patients With Left Ventricular Assist Device

Introduction: Heart failure patients implanted with an axial or centrifugal left ventricular assist device (LVAD) are treated with warfarin to prevent pump thrombosis. Given the propensity for gastrointestinal bleeding with these patients, careful management of anticoagulation is an essential part of post-operative care. Given the intense involvement of these patients and care-givers, we hypothesized that home monitoring of international normalized ratio (INR) may be more effective than traditional laboratory testing. Methods: We performed a retrospective study of 42 LVAD patients for a six-month period at The Christ Hospital in Cincinnati, OH. INR targets were patient-specific based on clinical history. Twenty-six patients used home testing (HOME: Roche, Alere) with guidance from the LVAD team while 16 patients were monitored using laboratory INR testing (LAB). Monitoring choice was based on patient/physician preference and insurance coverage. Results: Home monitored patients were tested fewer times over the 6 month period than the laboratory group (27 versus 37). In the HOME group, 52% of the INR's were within target range and 48% were outside (26% above and 22% below target). In the LAB group, 36% of INR's were within range and 64% were outside (27% above and 37% below target). Accordingly, percentage of patients experiencing either a bleeding or thrombotic complication was less common in the HOME group compared to LAB (15% versus 25%). Number of thrombotic complications was similar between the two groups, but bleeding complications were less frequent in the HOME group (3 in 26 patients) vs. LAB (7 in 16 patients). Conclusions: LVAD Patients monitored for INR at home required fewer tests, were more likely to be in therapeutic range, and suffered fewer bleeding complications. Relatively low rate of in-target INR's are likely related to narrow ranges and multiple patient factors.

SmartFABER: Recognizing fine-grained abnormal behaviors for early detection of mild cognitive impairment.

In an ageing world population more citizens are at risk of cognitive impairment, with negative consequences on their ability of independent living, quality of life and sustainability of healthcare systems. Cognitive neuroscience researchers have identified behavioral anomalies that are significant indicators of cognitive decline. A general goal is the design of innovative methods and tools for continuously monitoring the functional abilities of the seniors at risk and reporting the behavioral anomalies to the clinicians. SmartFABER is a pervasive system targeting this objective. A non-intrusive sensor network continuously acquires data about the interaction of the senior with the home environment during daily activities. A novel hybrid statistical and knowledge-based technique is used to analyses this data and detect the behavioral anomalies, whose history is presented through a dashboard to the clinicians. Differently from related works, SmartFABER can detect abnormal behaviors at a fine-grained level. We have fully implemented the system and evaluated it using real datasets, partly generated by performing activities in a smart home laboratory, and partly acquired during several months of monitoring of the instrumented home of a senior diagnosed with MCI. Experimental results, including comparisons with other activity recognition techniques, show the effectiveness of SmartFABER in terms of recognition rates.

Living Labs: Concepts, Tools and Cases

This paper introduces the concept, predecessors, and characteristics of Living Labs. It gives an overview of the predecessors of Living Labs from the 1970s onwards (cooperative design, social experiments, digital city initiatives and home labs) and compares them with the current definition of European Living Labs. This editorial also introduces all papers from the special issue.

A new home energy management algorithm with voltage control in a smart home environment

Energy management in electrical systems is one of the important issues for energy efficiency and future grid systems. Energy management is defined as a HEM (home energy management) on the residential consumer side. The HEM system plays a key role in residential demand response applications. In this study, a new HEM algorithm is proposed for smart home environments to reduce peak demand and increase the energy efficiency. The proposed algorithm includes VC (voltage control) methodology to reduce the power consumption of residential appliances so that the shifting of appliances is minimized. The results of the survey are used to produce representative load profiles for a weekday and for a weekend. Then, case studies are completed to test the proposed HEM algorithm in reducing the peak demand in the house. The main aim of the proposed HEM algorithm is to minimize the number of turned-off appliances to decrease demand so that the customer comfort is maximized. The smart home laboratory at Yildiz Technical University, Istanbul, Turkey is used in case studies. Experimental results show that the proposed HEM algorithm reduces the peak demand by 17.5% with the voltage control and by 38% with both the voltage control and the appliance shifting.

Living labs: concepts, tools and cases

This paper introduces the concept, predecessors, and characteristics of Living Labs. It gives an overview of the predecessors of Living Labs from the 1970s onwards (cooperative design, social experiments, digital city initiatives and home labs) and compares them with the current definition of European Living Labs. This editorial also introduces all papers from the special issue.

The Role of Noninvasive Ventilation in the Management and Mitigation of Exacerbations and Hospital Admissions/Readmissions for the Patient With Moderate to Severe COPD (Multimedia Activity)

As seen in this CME online activity (available at http://journal.cme.chestnet.org/home-niv-copd), COPD is a common and debilitating disease and is currently the third leading cause of death in the United States. The role of noninvasive ventilation (NIV) in the management of severe, hypercapnic COPD has been controversial. However, it was concluded that current data would support the following recommendations. Patients with COPD with a waking Paco2 > 50 to 52 mm Hg, an overnight Paco2 > 55 mm Hg, or both who are symptomatic and compliant with other therapies should be eligible for NIV. In addition, multiple previous hospital admissions for COPD exacerbation, requiring noninvasive/invasive mechanical ventilation, strongly suggest a need for chronic NIV. Patients with COPD with a BMI > 30 kg/m2 respond particularly well to this therapy. When the decision is made to start NIV, this treatment is probably best initiated during a short hospitalization, although this can be accomplished in the clinic, home, or sleep laboratory if well-trained clinicians are available. Newer modes of NIV such as volume-assured pressure support, particularly with autotitrating expiratory positive airway pressure (EPAP), may create the opportunity for home NIV initiation easier for less experienced physicians. Regardless of the mode selected, inspiratory pressures must be in the 20 to 25 cm H2O range to meaningfully increase tidal volume, reduce work of breathing, and, importantly, reduce waking arterial Paco2. EPAP is currently set at 4 to 5 cm H2O, although future technologies may allow this to be individualized to maximally reduce auto-positive end expiratory pressure. The NIV device should have a backup rate although it is controversial as to whether this should be set at a high (18-20 breaths/min) vs a low (8-10 breaths/min) rate. The proper use of NIV in appropriately chosen patients with COPD can improve quality of life and increase survival. Ongoing studies are assessing if the frequency of future hospitalizations can be reduced with NIV. Thus, NIV should be strongly considered in any patients with COPD meeting the criteria described here.

The use of Social Networking Sites (SNSs) by the faculty members of the School of Library &amp; Information Science, PAAET, Kuwait

Purpose– The purpose of this study is to describe the usage of Social Networking Sites (SNSs) by the faculty members of the School of Library and Information Science (SLIS), at the College of Basic Education, the Public Authority for Applied Education and Training (PAAET), Kuwait.Design/methodology/approach– A survey conducted to collect data from 33 faculty members of whom only 21 members were using SNSs, representing 63.6 per cent of the total sample, and 12 members were not using SNSs, representing 36.4 per cent of the total sample. This study revealed that SNSs are used moderately by the faculty members.Findings– This study showed that faculty members who were using SNSs tend to be males, aged between 41 and 50 years, PhD holders, ranked as assistant professors, full-time members, specialized in information technologies with a relatively new experience of teaching ranged from one to five years, and most of the faculty members who were not using SNSs tended to be also males, aged between 41 and 60 years, PhD holders, ranked as lecturers, full-time members specialized in organization of information with a teaching experience ranged from 16 to 20 years. More than half of the faculty members were using SNSs for three years to less than six years, and a large number of them were using SNSs several times a week and were accessing these sites more from their school office, home and school laboratory. There are no any statistical significant differences between the demographic data of participants (gender, age and education level) and either their use or non-use of SNSs. There are no significant differences between the academic rank, teaching status and teaching experience of faculty and their use of SNSs. However, there is a significant relation between the faculty’s area of teaching and their use of SNSs. Faculty members were interested in the use of SNSs. YouTube, Twitter, Facebook and blogs respectively were used mostly by faculty members, but Twitter, Facebook and YouTube were the most famous SNSs they have profiles on. Faculty members have adopted SNSs mainly for the purpose of communicating with others, finding and sharing information with peers and students as well. Tasks on SNSs made by faculty members were mostly to make communication, send/receive messages and find general and specific information. Faculty members’ profiles on SNSs were mostly on Twitter, Facebook, YouTube, blogs, wikis and podcasting respectively. Faculty members confirmed that the use of YouTube, Facebook, blogs, Twitter, wikis and podcasting respectively was at least effective and the use of YouTube, Facebook, Twitter, Blogs and Wikis respectively was at least fairly useful fairly easy to them. Faculty members are in general agreement about the effectiveness of SNSs especially for disseminating and sharing information, communication and informal collaboration. The study showed also that there is no gender-related difference among the faculty in terms of their usage of SNSs. The study revealed also that the time was the most important barrier both SNSs users and non-users faced at PAAET’s SLIS. Other barriers like trust about SNSs, training and skills were significant to SNSs users in this study, and barriers like interests in SNSs, awareness of them and trust about them were respectively the most important barriers to SNSs non-users. The study recommended that a further research is needed to examine more additional aspects of using SNSs among faculty members that may affect their use like the technical, legal, ethical and intellectual aspects. More information is needed to investigate why some faculty members do not use SNSs especially for educational purposes. A qualitative study of the perception and opinions of faculty members would provide much important data about that. A further research is also needed to specify the relation between the use of these sites and each area of study separately. Due to the lack of awareness and knowledge about the use of SNSs, shortage of language skills and training, this study recommended that SNSs non-users should be provided with necessary assistance to foster their skills towards such usage. A future study is needed to compare experiences of faculty members and students regarding the use of SNSs in educational practices and may look at how communicational uses of these sites have influenced educational uses.Research limitations/implications– This study involved a single and certain academic institution, namely PAAET. Therefore, findings, conclusions and recommendations may not be applicable and reasonable to be generalized on all Kuwaiti academic institutions.Social implications– This paper provides valuable insight into the usage of SNSs by a very important client group.Originality/value– This study is the first one of its kind conducted about the usage of SNSs by faculty members at a library school of one of the two public academic institutions in the state of Kuwait to examine and investigate more specific information about SNSs and related innovative topics.

Abstract O.70: Safey and Efficacy of Warfarin Therapy in Kawasaki Disease

Purpose: Giant aneurysms are managed with combined anticoagulation and anti-platelet therapy, heightening risk of bleeding complications. We sought to describe the safety and efficacy of warfarin for Kawasaki disease (KD) patients (pts) with giant coronary artery aneurysms (CAA, ≥8 mm). Methods: We reviewed the % time in therapeutic range (%TTR); % of INR’s in range; bleeding events, categorized as major bleeding, clinically-relevant non-major bleeding, and minor bleeding; clotting events; INRs ≥5; and INRs &lt;1.5. Results: Our anticoagulation service managed 9 KD pts (5 male), median age 13.2 y (range 7-22 y). INR testing was prescribed weekly to monthly and was done by home monitor (n=6) or lab (n=3). Median length of warfarin therapy was 6.5 y (1.6-12.5). Goal INR was 2.0-3.0 (n=6) or 2.5-3.5 (n=3), based on CAA size and history of CAA thrombosis. All pts were treated with aspirin; 1 was on triple therapy with warfarin, aspirin, and clopidogrel. From 6/2011-6/2014, the median %INRs in range was 62% (34-93%), and median %TTR was 68%(53-92%). INRs &gt;6 occurred in 2 pts (2 events); INRs 5 &lt;6 in 5 pts (9 events); and INRs &lt;1.5 in 5 pts (21 events) . During warfarin therapy, 3 major bleeding events occurred in 3 pts: 1 hemorrhage in calf muscle with compartment syndrome requiring surgical clot evacuation (INR 2.5); 1 hemorrhagic ovarian cyst needing hospitalization and Vit K (INR 5.2); and 1 hemopericardium (INR 2.8) 9 days post CABG requiring readmission to the hospital, pericardiocentesis and blood transfusion. There were 2 clinically-relevant non-major bleeding events in 2 pts: 1 hospitalized for bleeding 1 wk after wisdom teeth extraction (INR 6.1) and 1 requiring cauterization for nose bleeds. Minor bleeding events included: a) severe recurrent nosebleeds in 3 pts, causing 4 ER visits (2 pts) and Hgb fall to 7 mg/dL (1 pt, Fe treatment); and b) heavy menses in the 2 post-pubertal females, both treated with oral contraceptives. Four of 9 pts had no bleeding events, and no pt had new CAA thrombosis. Conclusions: Bleeding complications are common in pts on warfarin and aspirin. Despite management by a hospital anticoagulation service, INRs were in range only 2/3 of the time. Studies on oral Factor Xa inhibitors as an alternative to warfarin are needed in this at-risk population.

Comparison between home and hospital set-up for unattended home-based polysomnography: a prospective randomized study

BackgroundUnattended home-based polysomnography (H-PSG) is a reliable tool for the diagnosis of obstructive sleep apnoea (OSA). The quality of the recording can be influenced by several factors including the set-up location – at home versus in the sleep laboratory. Previous studies have suggested that the failure rate is higher when H-PSG is fitted in hospital. The aim of this study was to determine the influence of hook-up location on H-PSG recording quality. Feasibility and repeatability of H-PSG were also assessed. MethodsConsecutive patients suspected of OSA were selected. Each patient underwent two H-PSGs within two weeks, one fitted at home and one fitted in the sleep laboratory. The order of H-PSG was randomly assigned. ResultsAmong the 102 included patients, 95 completed the study. Ninety-three per cent of the 190 H-PSGs were satisfactory. The failure rate of H-PSG was similar for both the home set-up and the sleep laboratory set-up (p = 0.33). Seventy-nine per cent of patients opted to be fitted at home. OSA was diagnosed in 59%. The apnoea–hypopnoea index was similar for home and sleep laboratory set-up, resulting in a very good reproducibility (intraclass correlation coefficient of 0.85). No differences in total sleep time and sleep architecture were observed in both set-up protocols. Except for sleep duration, which was longer in the first H-PSG test, we did not observe any first-night effect during the first H-PSG. ConclusionThe present study demonstrates that hospital hook-up is as effective as home hook-up for home-unattended polysomnography, and that feasibility and repeatability of H-PSG are very good.

Increased photoelectron transmission in High-pressure photoelectron spectrometers using “swift acceleration”

A new operation mode of a HPXPS (high-pressure X-ray photoelectron spectroscopy) analyzer is evaluated on a HPXPS system fitted with an Al Kα X-ray source. A variety of metal foil samples (gold, silver and copper) were measured in different sample gas environments (N2 and H2O), and a front aperture diameter of 0.8mm. The new design concept is based upon “swiftly” accelerating the photoelectrons to kinetic energies of several keV after they pass the analyzer front aperture. Compared to the standard mode, in which the front section between the two first apertures is field-free, this gives a wider angular collection and a lower tendency for electron losses in collisions with gas molecules within the analyzer. With the swift-acceleration mode we attain, depending on the experimental conditions, up to about 3 times higher peak intensities in vacuum and about 10 to 20 times higher peak intensities in the 6–9mbar regime, depending on kinetic energy. These experimental findings agree well with simulated transmission functions for the analyzer. The new mode of operation enables faster data acquisition than the standard mode of operation, particularly valuable in a home laboratory environment. Further demonstrations of performance are highlighted by measurements of the valence band structure in dye-sensitized solar cell photoelectrodes under a 2mbar H2O atmosphere, a molecularly modified surface of interest in photoelectrochemical devices.

Hard disk drive based microsecond X-ray chopper for characterization of ionization chambers and photodiodes.

A fast X-ray chopper capable of producing ms long X-ray pulses with a typical rise time of few μs was realized. It is ideally suited to investigate the temporal response of X-ray detectors with response times of the order of μs to ms, in particular, any kind of ionization chambers and large area photo diodes. The drive mechanism consists of a brushless DC motor and driver electronics from a common hard disk drive, keeping the cost at an absolute minimum. Due to its simple construction and small dimensions, this chopper operates at home lab based X-ray tubes and synchrotron radiation sources as well. The dynamics of the most important detectors used in time resolved X-ray absorption spectroscopy, namely, ionization chambers and Passivated Implanted Planar Silicon photodiodes, were investigated in detail. The results emphasize the applicability of this X-ray chopper.

Diagnosis of Obstructive Sleep Apnea in Parkinson's Disease Patients: Is Unattended Portable Monitoring a Suitable Tool?

Purpose. Obstructive sleep apnea (OSA) is frequent in Parkinson's disease (PD) and may contribute to nonmotor symptoms. Polysomnography (PSG) is the gold standard for OSA diagnosis. Unattended portable monitoring (PM) may improve access to diagnosis but has not been studied in PD. We assessed feasibility and diagnostic accuracy in PD. Methods. Selected PD patients without known OSA underwent home PM and laboratory PSG. The quality of PM signals (n = 28) was compared with matched controls. PM accuracy was calculated compared with PSG for standard apnea hypopnea index (AHI) thresholds. Results. Technical failure rate was 27.0% and airflow signal quality was lower than in controls. Sensitivity of PM was 84.0%, 36.4%, and 50.0% for AHI cut-offs of 5/h, 15/h, and 30/h, respectively, using the same cut-offs on PM. Specificity was 66.7%, 83.3%, and 100%, respectively. PM underestimated the AHI with a mean bias of 12.4/h. Discrepancy between PM and PSG was greater in those with more motor dysfunction. Conclusion. PM was adequate to “rule in” moderate or severe OSA in PD patients, but the failure rate was relatively high and signal quality poorer than in controls. PM overall underestimated the severity of OSA in PD patients, especially those with greater motor dysfunction.