Room Temperature Gas Phase Equilibrium Constants of the Methanol Dimer, Trimer, and Tetramer.

We have detected the methanol dimer, trimer, and tetramer at equilibrium conditions at room temperature in the gas phase using direct absorption Fourier transform infrared spectroscopy. The infrared intensity of the OH-stretching transitions are enhanced upon hydrogen bonding and are increasingly red-shifted with increasing cluster size, facilitating identification and quantification of the various clusters. We calculate the intensities of the bound OH-stretches, OHb, for all clusters with a range of reduced dimensional vibrational models with different levels of electronic structure theory. Partial pressures of the clusters are obtained by scaling the measured integrated absorbance of the OHb-stretching bands by the calculated intensities of the associated vibrational transitions. We estimate the methanol dimer equilibrium constant, KD, to be 0.033, at 298.15 K, which is comparable to that of the water dimer. For the methanol trimer and tetramer, we estimate equilibrium constants for aggregation of monomers of KT ∼ 0.04 and KQ ∼ 0.6, respectively.

Erratum: Local Anesthetic Thoracoscopy for Undiagnosed Pleural Effusion.

An erratum was issued for: Local Anesthetic Thoracoscopy for Undiagnosed Pleural Effusion. The Authors section was updated from: Uffe Bodtger1,2 José M. Porcel3 Rahul Bhatnagar4,5 Mohammed Munavvar6,7 Casper Jensen1 Paul Frost Clementsen1,8 Daniel Bech Rasmussen1,2 1Respiratory Research Unit PLUZ, Department of Respiratory Medicine, Zealand University Hospital 2Institute of Regional Health Research, University of Southern Denmark 3Pleural Medicine Unit, Department of Internal Medicine, Hospital Universitari Arnau de Vilanova, IRBLleida 4Respiratory Department, Southmead Hospital, North Bristol NHS Trust 5Academic Respiratory Unit, University of Bristol 6Lancashire Teaching Hospitals 7University of Central Lancashire 8Centre for HR and Education, Copenhagen Academy for Medical Education and Simulation to: Uffe Bodtger1,2 José M. Porcel3 Rahul Bhatnagar4,5 Nick Maskell4,5 Mohammed Munavvar6,7 Casper Jensen1 Paul Frost Clementsen1,8 Daniel Bech Rasmussen1,2 1Respiratory Research Unit PLUZ, Department of Respiratory Medicine, Zealand University Hospital 2Institute of Regional Health Research, University of Southern Denmark 3Pleural Medicine Unit, Department of Internal Medicine, Hospital Universitari Arnau de Vilanova, IRBLleida 4Respiratory Department, Southmead Hospital, North Bristol NHS Trust 5Academic Respiratory Unit, University of Bristol 6Lancashire Teaching Hospitals 7University of Central Lancashire 8Centre for HR and Education, Copenhagen Academy for Medical Education and Simulation.

Pleural disease.

The incidence of pleural disease is increasing and the mortality and morbidity is high. Many recent RCTs have resulted in evidence-based guidelines published in 2023, pointing towards a more individualized and specialized management. Most patients with pleural disease are admitted at the A and E but can be managed in outpatient clinics. Thus, there is a need to establish specialized, multidisciplinary pleural clinics to ensure optimal, individualized and evidence-based management of the increasing number of patients with pleural disease in Denmark, as argued in this review.

Effect of Temperature on the OH-Stretching Bands of the Methanol Dimer.

We present a conceptually simple model for understanding the significant spectral changes that occur with the temperature in the infrared spectra of hydrogen-bound complexes. We have measured room-temperature spectra of the methanol dimer and two deuterated isotopologues in the OH(D)-stretching region. We correctly predict spectral changes observed in the gas phase for the bound OH stretch in the methanol dimer from jet-cooled to room temperature and corroborate this with experimental and theoretical results for deuterated isotopologues. The origin of the observed spectral features is explained based on a reduced-dimensional vibrational model, which includes the two high-frequency OH stretches, the two methyl torsions, and the six intermolecular low-frequency vibrations. Key to the success of the model is a new coordinate definition to describe the intrinsic large-amplitude curvilinear motion of low-frequency vibrations. Despite the deceivingly simple appearance of the room temperature bound OH-stretching fundamental band, it consists of ∼107 vibrational transitions.

Local Anesthetic Thoracoscopy for Undiagnosed Pleural Effusion.

Local anesthetic thoracoscopy (LAT) is a minimally invasive diagnostic procedure gaining recognition among chest physicians for managing undiagnosed pleural effusions. This single-port procedure is conducted with the patient under mild sedation and involves a contralateral decubitus position. It is performed in a sterile setting, typically a bronchoscopy suite or surgical theater, by a single operator with support from a procedure-focused nurse and a patient-focused nurse. The procedure begins with a thoracic ultrasound to determine the optimal entry point, usually in the IV-V intercostal space along the midaxillary line. Lidocaine/mepivacaine, with or without adrenaline, is used to anesthetize the skin, thoracic wall layers, and parietal pleura. A designated trocar and cannula are inserted through a 10 mm incision, reaching the pleural cavity with gentle rotation. The thoracoscope is introduced through the cannula for systematic inspection of the pleural cavity from the apex to the diaphragm. Biopsies (typically six to ten) of suspicious parietal pleura lesions are obtained for histopathological evaluation and, when necessary, microbiological analysis. Biopsies of the visceral pleura are generally avoided due to the risk of bleeding or air leaks. Talc poudrage may be performed before inserting a chest tube or indwelling pleural catheter through the cannula. The skin incision is sutured, and intrapleural air is removed using a three-compartment or digital chest drainage system. The chest tube is removed once there is no airflow, and the lung has satisfactorily re-expanded. Patients are usually discharged after 2-4 h of observation and followed up on an outpatient basis. Successful LAT relies on careful patient selection, preparation, and management, as well as operator education, to ensure safety and a high diagnostic yield.

Gas-Phase Room-Temperature Detection of the tert-Butyl Hydroperoxide Dimer.

We have detected the tert-butyl hydroperoxide dimer, (t-BuOOH)2, in the gas phase at room temperature using conventional FTIR techniques. The dimer is identified by an asymmetric absorbance band assigned to the fundamental hydrogen-bound OHb-stretch. The weighted band maximum of the dimer OHb-stretch is located at ∼3452 cm-1, red-shifted by ∼145 cm-1 from the monomer OH-stretching band. The gas-phase dimer assignment is supported by Ar matrix isolation FTIR experiments at 12 K and experiments with a partially deuterated sample. Computationally, we find the lowest energy structure of (t-BuOOH)2 to be a doubly hydrogen bound six-membered ring with non-optimal hydrogen bond angles. We estimate the gas-phase constant of dimer formation, K, to be 0.4 (standard pressure of 1 bar) using the experimental integrated absorbance and a theoretically determined oscillator strength of the OHb-stretching band.

Hospital admission for COVID-19 pneumonitis - long-term impairment in quality of life and lung function.

BACKGROUND AND AIM: Knowledge of long-term consequences of severe COVID-19 pneumonitis is of outmost importance. Our aim was, therefore, to assess the long-term impact on quality of life and lung function in adults hospitalized with severe COVID-19. METHODS: All patients hospitalized with COVID-19 pneumonitis at Copenhagen University Hospital-Hvidovre, Denmark, were invited to participate in the study 4-5 months after discharge. Of the 160 invited 128 responded positively (80%). Medical history and symptoms were assessed, and patients rated impact on quality of life and functional status with EuroQol-5D-5L and Post Covid Functional Scale. Lung function was assessed by dynamic spirometry and measurement of diffusing capacity. RESULTS: Fatigue, dyspnea, cough and cognitive dysfunction were the most common symptoms. Of 128 patients, 85% had at least one symptom, and 51% reported two or more symptoms. Self-rated Quality of life was impaired assessed by EuroQol 5D-5L, with dimensions 'Pain or discomfort' (61%) and 'Usual activities' (54%) mostly affected. Functional status was significantly worse than before COVID-19 assessed by Post-COVID Functional Scale. Among lung function parameters, diffusing capacity was most affected, with 45% having diffusing capacity < 80% of predicted. CONCLUSION: Fatigue, respiratory symptoms and cognitive symptoms are highly common months after hospitalization for severe COVID-19. Compared to pre-COVID-19, functional status and usual activities continued to be impaired. In line with this, almost half of the patients were found to have impaired diffusing capacity.

Airborne environmental DNA for terrestrial vertebrate community monitoring.

Biodiversity monitoring at the community scale is a critical element of assessing and studying species distributions, ecology, diversity, and movements, and it is key to understanding and tracking environmental and anthropogenic effects on natural ecosystems.1-4 Vertebrates in terrestrial ecosystems are experiencing extinctions and declines in both population numbers and sizes due to increasing threats from human activities and environmental change.5-8 Terrestrial vertebrate monitoring using existing methods is generally costly and laborious, and although environmental DNA (eDNA) is becoming the tool of choice to assess biodiversity, few sample types effectively capture terrestrial vertebrate diversity. We hypothesized that eDNA captured from air could allow straightforward collection and characterization of terrestrial vertebrate communities. We filtered air at three localities in the Copenhagen Zoo: a stable, outside between the outdoor enclosures, and in the Rainforest House. Through metabarcoding of airborne eDNA, we detected 49 vertebrate species spanning 26 orders and 37 families: 30 mammal, 13 bird, 4 fish, 1 amphibian, and 1 reptile species. These spanned animals kept at the zoo, species occurring in the zoo surroundings, and species used as feed in the zoo. The detected species comprise a range of taxonomic orders and families, sizes, behaviors, and abundances. We found shorter distance to the air sampling device and higher animal biomass to increase the probability of detection. We hereby show that airborne eDNA can offer a fundamentally new way of studying and monitoring terrestrial communities.

Coupling of torsion and OH-stretching in tert-butyl hydroperoxide. II. The OH-stretching fundamental and overtone spectra.

The vibrational spectra of gas phase tert-butyl hydroperoxide have been recorded in the OH-stretching fundamental and overtone regions (ΔvOH = 1-5) at room temperature using conventional Fourier transform infrared (ΔvOH = 1-3) and cavity ring-down (ΔvOH = 4-5) spectroscopy. In hydroperoxides, the OH-stretching and COOH torsion vibrations are strongly coupled. The double-well nature of the COOH torsion potential leads to tunneling splitting of the energy levels and, combined with the low frequency of the torsional vibration, results in spectra in the OH-stretching regions with multiple vibrational transitions. In each of the OH-stretching regions, both an OH-stretching and a stretch-torsion combination feature are observed, and we show direct evidence for the tunneling splitting in the OH-stretching fundamental region. We have developed two complementary vibrational models to describe the spectra of the OH-stretching regions, a reaction path model and a reduced dimensional local mode model, both of which describe the features of the vibrational spectra well. We also explore the torsional dependence of the OH-stretching transition dipole moment and show that a Franck-Condon treatment fails to capture the intensity in the region of the stretch-torsion combination features. The accuracy of the Franck-Condon treatment of these features improves with increasing ΔvOH.

Coupling of torsion and OH-stretching in tert-butyl hydroperoxide. I. The cold and warm first OH-stretching overtone spectrum.

The infrared (IR) spectrum of tert-butyl hydroperoxide (TBHP) in the region of the first OH-stretching overtone has been observed under jet-cooled and thermal (300 K, 3 Torr) conditions at ∼7017 cm-1. The jet-cooled spectrum is recorded by IR multiphoton excitation with UV laser-induced fluorescence detection of OH radical products, while direct IR absorption is utilized under thermal conditions. Prior spectroscopic studies of TBHP and other hydroperoxides have shown that the OH-stretch and XOOH (X = H or C) torsion vibrations are strongly coupled, resulting in a double well potential associated with the torsional motion about the OO bond that is different for each of the OH-stretching vibrational states. A low barrier between the wells on the torsional potential results in tunneling split energy levels, which leads to four distinct transitions associated with excitation of the coupled OH-stretch-torsion states. In order to interpret the experimental results, two theoretical models are used that include the OH-stretch-torsion coupling in TBHP. Both methods are utilized to compute the vibrational transitions associated with the coupled OH-stretch-torsion states of TBHP, revealing the underlying transitions that compose the experimentally observed features. A comparison between theory and experiment illustrates the necessity for treatments that include OH-stretch and COOH torsion in order to unravel the spectral features observed in the first OH-stretching overtone region of TBHP.

A flood of models: Mekong ecologies of comparison.

In recent decades, scientists have developed a wide array of hydrological, hydrodynamic, and other models to understand the dynamics of the Mekong River Basin. Indeed, the area has been described as 'flooded' with models. Drawing on STS and the philosophy of modeling - which has described models as mediating instruments - the first half of this article discusses how and why this proliferation has occurred, focusing on the Cambodian context. Highlighting that models are developed comparatively, with reference to one another, the analysis shows how they have generated a partially connected ecology of comparisons. As each model makes its own image of the Mekong, the ecology as a whole creates a kaleidoscopic effect. In principle, this ecology is important for that of environmental policy-making. In practice, however, it is tremendously difficult for scientists to bridge the ecologies. Examining two cases of NGO-based modeling aiming to influence policy, the second half of the paper offers a comparative analysis of the challenges modeling knowledge faces in Mekong environmental politics.

Using Polarized Spectroscopy to Investigate Order in Thin-Films of Ionic Self-Assembled Materials Based on Azo-Dyes.

Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.

Characterization of the Glucagonlike Peptide-1 Receptor in Male Mouse Brain Using a Novel Antibody and In Situ Hybridization.

Glucagonlike peptide 1 (GLP-1) is a physiological regulator of appetite, and long-acting GLP-1 receptor (GLP-1R) agonists lower food intake and body weight in both human and animal studies. The effects are mediated through brain GLP-1Rs, and several brain nuclei expressing the GLP-1R may be involved. To date, the mapping of the complete location of GLP-1R protein in the brain has been challenged by lack of good antibodies and the discrepancy between mRNA and protein, especially relevant in neuronal axonal processes. Here, we present a specific monoclonal GLP-1R antibody for immunohistochemistry with murine tissue and show detailed distribution of GLP-1R expression, as well as mapping of GLP-1R mRNA by nonradioactive in situ hybridization. Semiautomated image analysis was performed to map the GLP-1R distribution to atlas plates from the Allen Institute for Brain Science. The GLP-1R was abundantly expressed in numerous regions, including the septal nucleus, hypothalamus, and brain stem. GLP-1R protein expression was also observed on neuronal projections in brain regions devoid of any mRNA that has not been observed in earlier reports. Taken together, these findings provide knowledge on GLP-1R expression in neuronal cell bodies and neuronal projections.

Skin blood perfusion and cellular response to insertion of insulin pen needles with different diameters.

Today most research on pen needle design revolves around pain perception statements through clinical trials, but these are both costly, timely, and require high sample sizes. The purpose of this study was to test if tissue damage, caused by different types of needles, can be assessed by evaluating skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after the insertions. Seven pigs were included in the study and a total of 118 randomized needle insertions were conducted. Histology was made of tissue samples inserted with 18G, 28G, and 32G needles, and stained to quantify red and white blood cell response. Based on area under curve, calculated for each individual blood perfusion recording and grouped according to needle type, skin blood perfusion response relates to needle diameter. The response was significantly higher after insertions with 28G and hooked 32G needles than with 30G (P < .05) and 32G (P < .01) needles. Histology results were not significant, but there was a trend of an increased response with increasing needle diameter. Skin blood perfusion response to pen needle insertions rank according to needle diameter, and the tissue response caused by hooked 32G needles corresponds to that of 28G needles. The relation between needle diameter and trauma when analyzing histology was also suggested.

Sociology, systems and (patient) safety: knowledge translations in healthcare policy.

In 2000 the American Institute of Medicine, adviser to the federal government on policy matters relating to the health of the public, published the report To Err is Human: Building a Safer Health System, which was to become a call to arms for improving patient safety across the Western world. By re-conceiving healthcare as a system, it was argued that it was possible to transform the current culture of blame, which made individuals take defensive precautions against being assigned responsibility for error - notably by not reporting adverse events, into a culture of safety. The IOM report draws on several prominent social scientists in accomplishing this re-conceptualisation. But the analyses of these authors are not immediately relevant for health policy. It requires knowledge translation to make them so. This paper analyses the process of translation. The discussion is especially pertinent due to a certain looping effect between social science research and policy concerns. The case here presented is thus doubly illustrative: exemplifying first how social science is translated into health policy and secondly how the transformation required for this to function is taken as an analytical improvement that can in turn be redeployed in social research.

Power, technology and social studies of health care: an infrastructural inversion.

Power, dominance, and hierarchy are prevalent analytical terms in social studies of health care. Power is often seen as residing in medical structures, institutions, discourses, or ideologies. While studies of medical power often draw on Michel Foucault, this understanding is quite different from his proposal to study in detail the "strategies, the networks, the mechanisms, all those techniques by which a decision is accepted" [Foucault, M. (1988). In Politics, philosophy, culture: Interviews and other writings 1977-84 (pp. 96-109). New York: Routledge]. This suggestion turns power into a topic worth investigating in its own right rather than a basic analytical resource. It also suggests that technologies form an integral part of the networks and mechanisms, which produce and redistribute power in medical practice. The paper first engages critically with a number of recent discussions of technology and power in health care analysis. It then formulates an alternative conception of this relationship by drawing on Foucault and historian of science and technology Geoffrey C. Bowker's notions of infrastructural inversion and information mythology. Illustration is provided through a case study of a wireless nursing call system in a Canadian hospital.