bluuebunny/crossref_metadata_2025 huggingface dataset:
Cianobactérias Psâmicas Marinhas da Praia das Flexeiras, Estado do Rio de Janeiro, Sudeste do Brasil
Authors: Silva Loreine Hermida da Silva e , Alves Siglia Andressa Pinto Monteiro do Nascimento , Magina Fernanda Campante , Gomes Sinda Beatriz Vianna Carvalhal , Cardoso Ricardo Da Silva , Caetano Carlos Henrique Soares , Guarino Alcides Wagner Serpa
Published: July 2021

Flexeiras beach (22º56' S, 43º53'W) is located at Ilha de Itacuruçá (Itacuruçá Island) in Sepetiba Bay, on the southern coast of Rio de Janeiro State. It is a protected beach in relation to wave exposition, due to its geographic position, which faces the opening Bay. This work aims at contributing with the knowledge of abundance of psamic cyanobacteria species, which compound Brazilian sea-communities. It had occurred monthly collections, from December 2006 to January 2008, during syzygy's low tide. Samples were obtained through PVC pipes, measuring 1,5 cm of internal diameter and 6 cm length. They were also fractionated into 3 segments, 2 cm distant. After that, samples had been places in opaque plastic flasks referring to each segment and preserved in a 4% formol aqueous solution. Flexeiras beach has sediments made by sand, presenting grain size varying from 0,22 to 0,32 mm (fine sand). Estimated average declivity was of 1/21,4m (À 4,07) and 1/28,7m (À 15,8), respectively, for two transects. The water chlorophyll concentration in interdital areas presented an average of 3,03 g/L (À2,29) and total Phosphorus presented an average of 0,12 mg/L (À 0,04). Average salinity was of 35%, don't having considerable oscillations during the months studied. The qualitative analysis has detected the presence of 12 psamic cyanobacteria tax. Family Chroococcaceae Nägeli 1849 is the most frequent, responsible for 33,4% of encountered species. The geological importance of psamic cyanobacteria is intrinsically associated to the fact of them composing the first unconsolidated substract for microbial mats' formation, essential structures in this group preservation.
Distribuição das Diatomáceas Modernas nos Sedimentos da Baía de Guanabara e Áreas Oceânicas, Rio de Janeiro (Brasil)
Authors: Laut Lazaro L.M. , Laut Vanessa M. , Silva Frederico S. , Figueiredo Jr. Alberto G.
Published: July 2021

One hundred and fifty three superficial sediments were collected in Guanabara Bay to physical-chemistry and diatom analyses in the ambit to Monitoring Project (CENPES/PETROBRAS). A total of 146 taxa of diatoms were identified where the most frequent taxa in Guanabara Bay were Amphora spp., Coscinodiscus spp. and Navicula yarrensis var. yarrensis. These species are potentially harmful that might harm fisheries and mariculture during blooms. The values of ecological indexes like richness and diversity followed the estuarine gradient were the higher values were found in the mouth and de low in the inner part. The multivariate analyzes permitted recognize seven diatom assemblages in the bay. The DCA analyze shows the most influence in the distribution of assemblages were the depth and pH. The diatom assemblages analyze proved to be an efficient tool in the environmental diagnosis of Guanabara Bay.
Sítios Paleontológicos das Bacias do Rio do Peixe: Georreferenciamento, Diagnóstico de Vulnerabilidade e Medidas de Proteção
Authors: Siqueira Luis Manoel Paes , Polck Márcia Aparecida dos Reis , Hauch Andrea Cristina Giongo , Silva Cristiano Alves da , Chaves Felipe Barbi , Yamamoto Irma Tie , Araujo João Da Penha , Andrade José Artur Ferreira Gomes de , Filgueira José Betimar Melo , Trindade Maria Hilda Pinto de Arruda , Machado Rodrigo Da Rocha , Santucci Rodrigo Miloni
Published: July 2021

The abandoned state and depredation of the paleontological geosites at the Rio do Peixe basins have been for some time a reason for concern to authorities and the society. Removal of sand from the Monumento Natural Vale dos Dinossauros Park and removal of fossils from sites catalogued by SIGEP (Comissão Brasileira de Sítios Geológicos e Paleobiológicos) have been made public and recognized through this study. The aims of this paper are to: georeference the paleontological sites from the Rio do Peixe basins, provide a diagnostic of vunerability for these sites, and establish proposals for protection measures. Ten field work were carried out, in 2008 and 2009, by the technicians from DNPM. Besides a georeferenced map of the paleontological sites from the Rio do Peixe basins, nine factors that strongly contribute for the vulnerability of the sites were defined, the main ones being the natural action of weathering and the antropic action. Most of the studied sites have medium to high vulnerability degree. The most vulnerable site are: Pedregulho, Piau/Caiçara, Várzea dos Ramos, Lagoa dos Patos, Cabra Assada, and Matadouro. Currently, Matadouro Site can be considered a completely destroyed, being, its recovery no longer possible. Ten protection measures were proposed for these paleontological sites.
Stockscheider Quartzo-Moscovíticos e Pegmatíticos na Zona de Cúpula do Granitóide Ritápolis, Região de São João del Rei, Minas Gerais
Authors: Pereira Ronaldo Mello , Rodrigues Diana , Ávila Ciro Alexandre , Neumann Reiner
Published: July 2021

Clusters of essentially quartz-muscovitic rocks were found in four areas of the São João del Rei Pegmatite Province in close association with pegmatites positioned parallel to the contact between the Ritápolis granitoid and the metavolcanic - metasedimentary rocks of the Rio das Mortes greenstone belt. The suite of accessory minerals associated to the quartz-muscovite and pegmatite stockscheider (columbite-tantalite, cassiterite, gahnite, zircon, xenotime and monazite) are similar to those determined for the pegmatites of the province. The mineralogy of inclusions (Pb-tantalite, microlite, Pb-microlite, U-microlite, Ba-microlite, Hf-rich zircon) in the Fe-columbite associated to the stockscheider is similar to those determined for the Fe-columbite of the more evolved pegmatites found in the province. The quartz-muscovite and pegmatite stockscheider are related to Ritápolis granitoid with is related to the other pegmatites of São João del Rei Pegmatite Province. The proposed mechanism for the formation of clusters of muscovite-quartz and pegmatitic stockscheider is the crystallization of pockets of tardi-magmatic and pos-magmatic hydrothermal - metasomatic fluids segregated from the parental granitic magma and injected into fractures parallel to the roof contact of the granitoid dome.
Temperature–Humidity Coupled Analysis in Battery Pack Based on Airflow Characteristics of Waterproof Breathable Valve
Authors: Li Weijian , Lan Fengchong , Chen Jiqing
Published: July 2021

Waterproof breathable valves (WBV) are applied to the battery packs in electric vehicles due to their advantages of high efficiency waterproof and air pressure balance. With the continuity of mass transfer of WBV and uncertain thermal conditions, the dynamic thermal characteristic of the moisture inside the battery pack is difficult to obtain by experiments, especially the phase change of the moisture. To analyze WBV mass transfers to the temperature–humidity characteristic in the battery pack, this study presents a temperature–humidity coupling model of the battery pack based on the mass transfer characteristic of WBV. A mass transfer model of WBV is developed with the airflow mass transfer characteristic in air pressure difference. The proposed models verified the feasibility of dynamic thermal characteristic analysis with experiments. Finally, a practical case study on a battery pack is used to analyze dynamic characteristics of the temperature–humidity during idle and working. Using the coupling model and the WBV model, temperature–humidity distribution and the location and time attributes of moisture condensation in the battery pack are effectively obtained. The inner walls of the pack casing and the battery surface near WBV are condensation areas during environmental conditions changing.
Surface Roughness Impact on Boundary Layer Transition and Loss Mechanisms Over a Flat-Plate Under a Low-Pressure Turbine Pressure Gradient
Authors: Jeong Heechan , Song Seung Jin
Published: July 2021

An experimental study has been conducted to investigate the effects of surface roughness on the profile loss of a flat-plate with a contoured wall. All of the measurements have been conducted for the suction side pressure gradient of a high-lift low pressure turbine airfoil at the fixed freestream turbulence intensity (Tu) of 3.2% under Reynolds numbers of Rec = 1. 2 · 105 (cruise) and Rec = 5.2 · 105 (take-off). The time-resolved streamwise and wall-normal velocity fields for three different surface roughness values of Ra/C · 105 = 0.065, 4.417, and 7.428 have been measured with a 2D hot-wire probe. At the take-off condition (Rec = 5.2 · 105), attached flow transition occurs, and increased surface roughness increases the loss. For all of the surfaces, momentum deficits in the laminar to early transition region (γ ≈ 0.05) are similar. For the intermediate transition (γ ≈ 0.5), increased roughness reduces the Reynolds stress and accelerates the breakdown of large-scale turbulent spots into small-scale turbulent eddies. Therefore, turbulent energy and momentum deficit are decreased for rough surfaces. For the late transition (γ > 0.9), transitional boundary layers become similar to turbulent boundary layers, and increased surface roughness increases turbulent mixing, boundary layer thickness, and, hence, the momentum deficit. On the other hand, at the cruise condition (Rec = 1.2 · 105), separated flow transition occurs and increased surface roughness decreases loss. Since the portion of turbulent flow is relatively small, the overall profile loss is mainly determined by the momentum deficit generated during transition. Increased roughness decreases the maximum height and length of the separation bubble but does not affect the separation bubble onset location. The beneficial effects of increased surface roughness on the profile loss appear in the separated shear layer and reattachment. Increased surface roughness increases turbulent mixing in the separated shear layer, reducing the shear layer thickness and momentum deficit. In addition, increased surface roughness reduces the length scale and turbulence intensity of the shed vortices. Consequently, turbulent mixing and momentum deficit during the reattachment of boundary layers are decreased, resulting in a lower profile loss.
Experimental Investigation of the Effect of Heat Spreading on Boiling of a Dielectric Liquid for Immersion Cooling of Electronics
Authors: Ghaffari Omidreza , Tong Wei , Larimi Yaser Nabavi , al Sayed Chady , Ganjali Alireza , Morissette Jean-François , Grenier Francis , Jasmin Simon , Fréchette Luc , Sylvestre Julien
Published: July 2021

This paper investigated the effect of heat spreading on the boiling of the Novec 649™ for two-phase immersion cooling of electronics. Reference pool boiling tests were performed by attaching a 25.4 mm by 25.4 mm square copper plate to a same-sized heater, thus minimizing lateral heat spreading. Experimental measurements showed that the critical heat flux (CHF) happened at a heat flux of 17.4±0.8 W/cm2. Then, lateral heat spreading through the heat spreader was studied by attaching larger (47 mm by 47 mm) spreaders with four different thicknesses to the copper plate. With an increase in the integrated heat spreader (IHS) thickness from 1 mm to 6 mm, the CHF increased by more than 60% at the saturation condition. One plate was a 1 mm-thick IHS removed from a commercial microprocessor. In this case, the CHF happens at 8.6 W/cm2 (50% lower compared to the reference case) in the saturation condition. At CHF, the boiling can be observed on the whole surface, with columns and slugs regime at the center and the fully developed nucleate boiling regime at the edges. This nonuniform boiling was more pronounced in subcooled conditions, in which the CHF occurred at the center while there were regions at the edges that had no boiling. Finally, the performance of a microporous-coated IHS (with 3.15 mm thickness) was compared to the 6 mm thick IHS. The thermal resistance was almost equal for powers above 200 W. This indicates that lateral heat spreading is a critical parameter for the thermal design of immersion cooling along with microporous coating.
A Comparison Between Deep Learning and Support Vector Regression Techniques Applied to Solar Forecast in Spain
Authors: Lima Marcello Anderson F. B. , Fernández Ramírez Luis M. , Carvalho Paulo C. M. , Batista Josias G. , Freitas Deivid M.
Published: July 2021

Solar energy is one of the main renewable energy sources capable of contributing to global energy demand. However, the solar resource is intermittent, making its integration into the electrical system a difficult task. Here, we present and compare two machine learning techniques, deep learning (DL) and support vector regression (SVR), to verify their behavior for solar forecasting. Our testing from Spain showed that the mean absolute percentage error for predictions using DL and SVR is 7.9% and 8.52%, respectively. The DL achieved the best results for solar energy forecast, but it is worth mentioning that the SVR also obtained satisfactory results.
Low-Order Modeling of Can-Annular Combustors
Authors: Fournier Guillaume J. J. , Meindl Max , Silva Camilo F. , Ghirardo Giulio , Bothien Mirko R. , Polifke Wolfgang
Published: July 2021

Heavy-duty land-based gas turbines are often designed with can-annular combustors, which consist of a set of identical cans, acoustically connected on the upstream side via the compressor plenum, and, downstream, with a small annular gap located at the transition with the first turbine stage. The modeling of this cross-talk area is crucial to predict the thermo-acoustic modes of the system. Thanks to the discrete rotational symmetry, Bloch wave theory can be exploited to reduce the system to a longitudinal combustor with a complex-valued equivalent outlet reflection coefficient, which models the annular gap. The present study reviews existing low-order models based purely on geometrical parameters and compares them to two-dimensional Helmholtz simulations. We demonstrate that the modeling of the gap as a thin annulus is not suited for can-annular combustors and that the Rayleigh conductivity model only gives qualitative agreement. We then propose an extension for the equivalent reflection coefficient that accounts not only for geometrical but also flow parameters, by means of a characteristic length. The proposed model is in excellent agreement with two-dimensional simulations and is able to correctly capture the eigenfrequencies of the system. We then perform a Design of Experiments study that allows us to explore various configurations and build correlations for the characteristic length. Finally, we discuss the validity limits of the proposed low-order modeling approach.
Details of Shrouded Stator Hub Cavity Flow in a Multistage Axial Compressor Part 2: Leakage Flow Characteristics in Stator Wells
Authors: Kamdar Nitya , Lou Fangyuan , Key Nicole L.
Published: July 2021

The flow in shrouded stator cavities can be quite complex with axial, radial, and circumferential variations. As the leakage flow recirculates and is re-injected into the main flow path upstream of the stator, it deteriorates the near-hub flow field and, thus, degrades the overall aerodynamic performance of the compressor. In addition, the windage heating in the cavity can raise thermal-mechanical concerns. Fully understanding the details of the shrouded-hub cavity flow in a multistage environment can enable better hub cavity designs. In the first part of the paper, the influence of the hub leakage flow on compressor performance and its interactions with the primary flow were investigated. While the impact of hub leakage flow on the primary passage is readily available in the open literature, details inside the cavity geometry are scarce due to the difficulties in instrumenting that region for an experiment or modeling the full cavity geometry. To shed light on this topic, the flow physics in the stator cavity inlet and outlet wells are investigated in this paper using a coupled computational fluid dynamics model with the inclusion of the stator cavity wells for the Purdue 3-stage (P3S) axial compressor, which is representative of the rear stages of a high-pressure-compressor in core engines. At the inlet cavity, the presence of at least one pair of vortices influences the trajectory of the cavity leakage flow. The amount of leakage flow also determines the size of the vortical structures, with larger clearances creating a smaller vortex and vice versa. After passing through the labyrinth seals, the leakage flow travels along the stator landing first and then transitions to the rotor drum. In general, a flow path closer to the rotor drum achieves higher circumferential velocity but also exhibits significant temperature rise. A rise in circumferential velocity directly corresponds to a rise in temperature. In addition, the windage heating increases with increasing seal clearance. Furthermore, the inlet well contributes the most to overall windage, nearly 50% of the total windage heating, while the labyrinth seals and outlet well account for very little.
Acoustic-Convective Interference in Transfer Functions of Methane/Hydrogen and Pure Hydrogen Flames
Authors: Æsøy Eirik , Aguilar José G. , Bothien Mirko R. , Worth Nicholas A. , Dawson James R.
Published: July 2021

We investigate the occurrence and source of modulations in the gain and phase of flame transfer functions (FTF) measured in perfectly premixed, bluff body stabilized CH4/H2 and pure H2 flames. The modulations are shown to be caused by flow disturbances originating from the upstream geometry, in particular the grub screws used to center the bluff body, indicative of a more generalized phenomenon of convective wave propagation. Velocity measurements are performed at various locations around the injector dump plane, inside the injector pipe, and in the wake of the bluff body to provide detailed insight into the flow. Peaks corresponding to natural shedding frequencies of the grub screws appear in the unforced velocity spectra and it is found that the magnitude of these convective modes depends on their location. Flame imaging and PIV measurements show that these disturbances do not show up in the mean velocity and flame shape which appear approximately axisymmetric. However, the urms and vrms fields capture a strong asymmetry due to convective disturbances. To further quantify the role of these convective disturbances, hydrodynamic transfer functions are constructed from the forced cold flow, and similar modulations observed in the FTFs are found. A strong correlation is obtained between the two transfer functions, subsequently, the modulations are shown to be centered on the vortex shedding frequency corresponding to the first convective mode. The reason behind the excitation of the first mode is due to a condition that states that for acoustic-convective interaction to be possible, the shedding (convective) frequency needs to be lower than the cutoff frequency of the flame response. This condition is shown to be more relevant for hydrogen flames compared to methane flames due to their shorter flame lengths and thus increased cutoff frequency.
Synthesis of model sodium sulfide films
Authors: McAuliffe Rebecca D. , Petrova Victoria , McDermott Matthew J. , Tyler Jameson Landon , Self Ethan C. , Persson Kristin A. , Liu Ping , Veith Gabriel M.
Published: July 2021

We report the direct deposition of model sodium sulfide films by RF magnetron sputtering from Na2S and Na2S2 deposition targets. Analytical characterization and electrochemical cycling indicate that the deposited films are amorphous with stoichiometries that correspond to Na2S3 and Na2S2 formed from the Na2S and Na2S2 targets, respectively. We propose that the loss of Na in the case of the Na2S target is due to preferential sputtering of Na resulting from the higher energy required to break the Na–S bonds in Na2S. The development of thin film sodium sulfides opens a new route to understanding their fundamental properties, such as Na+ transport, conductivity, and reactivity.
Exercise and Heat Stress: Inflammation and the Iron Regulatory Response
Authors: McKay Alannah K.A. , McCormick Rachel , Tee Nicolin , Peeling Peter
Published: July 2021

This study determined the impact of heat stress on postexercise inflammation and hepcidin levels. Twelve moderately trained males completed three, 60-min treadmill running sessions under different conditions: (a) COOL, 18 °C with speed maintained at 80% maximum heart rate; (b) HOTHR, 35 °C with speed maintained at 80% maximum heart rate; and (c) HOTPACE, 35 °C completed at the average running speed from the COOL trial. Venous blood samples were collected pre-, post-, and 3-hr postexercise and analyzed for serum ferritin, interleukin-6 (IL-6), and hepcidin concentrations. Average HR was highest during HOTPACE compared with HOTHR and COOL (p < .001). Running speed was slowest in HOTHR compared with COOL and HOTPACE (p < .001). The postexercise increase in IL-6 was greatest during HOTPACE (295%; p = .003). No differences in the IL-6 response immediately postexercise between COOL (115%) and HOTHR (116%) were evident (p = .992). No differences in hepcidin concentrations between the three trials were evident at 3 hr postexercise (p = .407). Findings from this study suggest the IL-6 response to exercise is greatest in hot compared with cool conditions when the absolute running speed was matched. No differences in IL-6 between hot and cool conditions were evident when HR was matched, suggesting the increased physiological strain induced from training at higher intensities in hot environments, rather than the heat per se, is likely responsible for this elevated response. Environmental temperature had no impact on hepcidin levels, indicating that exercising in hot conditions is unlikely to further impact transient alterations in iron regulation, beyond that expected in temperate conditions.
Researcher, Coach Developer, and Coaches’ Perspectives on Learner-Centered Teaching in a Rugby Coach Education Program
Authors: Ciampolini Vitor , Camiré Martin , das Neves Salles William , do Nascimento Juarez Vieira , Milistetd Michel
Published: July 2021

In the sports coaching field, learner-centered teaching (LCT) has been advocated as a viable approach to increasing learners’ involvement in the learning process. However, implementing LCT is not a simple undertaking as coach developers, and coaches have encountered dilemmas when it comes to shifting to LCT in coach education. This study aimed to investigate how LCT principles were implemented in a rugby coach education program through the perspectives of the researcher, the coach developer, and coaches. Participants included the researcher (i.e., first author), a coach developer, and 10 rugby coaches. The researcher observed three coach education courses, gathered descriptive and reflective field notes, and conducted individual semistructured interviews with both the coach developer and the 10 coaches. Findings shed light on the strategies adopted by the coach developer and the extent to which these strategies aligned with LCT principles. Coaches discussed how they enjoyed their active role in the courses and the approaches used by the coach developer to leverage learning. The discussion highlights the importance of coach developers in facilitating a learning process that is challenging, motivating, and supports coaches throughout the courses.
Huge protein structure database could transform biology
Authors: Service Robert F.
Published: July 2021

DeepMind's AI surveyed the universe of human proteins, making high-confidence predictions for nearly half
The road to addressing Long Covid
Authors: Alwan Nisreen A.
Published: July 2021

Reporting, recognizing, and researching the chronic effects of COVID-19 will help those affected
Making and remaking life
Nature Remade
Luis A. Campos, Michael R. Dietrich, Tiago Saraiva, Christian C. Young, editors
University of Chicago Press, 2021. 320 pp.
Authors: Muka Samantha
Published: July 2021

The incorporation of engineering attitudes into biology shaped the modern life sciences
The post-antibiotic era is here
Authors: Kwon Jennie H. , Powderly William G.
Published: July 2021

Imagine a world where routine surgery or chemotherapy is considered too dangerous because there are no drugs to prevent or treat bacterial infections. Unless researchers develop new antibiotics and therapeutics, the decimation of modern medicine will soon become a reality. Scientists have long recognized that much stronger incentives for research and development are needed to avoid this scenario. Yet, the rise of “superbugs” has continued, making a pandemic of antibiotic resistance a major threat to global health.
Complete Genome Sequence of an
mcr-10-
Possessing Enterobacter roggenkampii Strain Isolated from a Dog in Japan
Authors: Sato Toyotaka , Usui Masaru , Harada Kazuki , Fukushima Yukari , Nakajima Chie , Suzuki Yasuhiko , Yokota Shin-ichi
Published: July 2021

The complete genome sequence of
mcr-10
-possessing
Enterobacter roggenkampii
En37, isolated from a dog in Japan was determined.
mcr-10
was located on a 70,277-bp IncFIB plasmid without any additional antimicrobial resistance genes.
Analysis of the Microbial Community Structure in Coastal Sediment of an Ascidian Farm in South Korea through 16S rRNA Gene Amplicon Sequencing
Authors: Jeong Ilwon , Kim Jong-Oh , Yoon Seokjin , Kim Kyunghoi
Published: July 2021

Aquaculture places contamination pressure on the coastal environment. We investigated the microbial community structure changes in sediment in an ascidian
Styela clava
farm. Data profiling of the 16S rRNA gene amplicon sequence shows that the microbial diversity of sediment in the
Styela clava
farm is dominated by
Proteobacteria
phyla (relative abundance, 95.34 to 97.85%).
Complete Genome Sequence of the Cytokinin-Producing Biocontrol Strain Pseudomonas fluorescens G20-18
Authors: Nielsen Tue K. , Mekureyaw Mengistu F. , Hansen Lars H. , Nicolaisen Mette H. , Roitsch Thomas G. , Hennessy Rosanna C.
Published: July 2021

Here, we report the complete genome sequence of the cytokinin-producing plant growth-promoting strain
Pseudomonas fluorescens
G20-18. The complete genome assembly resulted in a single, circular chromosome of 6.48 Mbp and harbors several secondary metabolite biosynthesis gene clusters that are potentially involved in its plant growth-promoting function.
Elderly woman presenting with multivessel coronary artery disease and Takotsubo syndrome
Authors: Vivekanantham Hari , Scoglio Martin , Suter Philipp , Cook Stephane , Roux Yann , Arroyo Diego
Published: July 2021

Takotsubo syndrome is an acute and often reversible condition, with initial presentation mimicking acute coronary syndrome. Typically, patients present with left ventricular regional wall motion abnormalities, without a corresponding coronary artery obstruction on angiography. Coexistence of a coronary artery disease is possible and may render the distinction between the two entities particularly challenging. We report the case of a 94-year-old woman with chest pain after an emotional upset and acute myocardial injury. Transthoracic echocardiogram (TTE) revealed a severely reduced left ventricular ejection fraction (LVEF) with apical ballooning. Coronary angiogram showed significant stenosis of the distal left main coronary artery and of the mid-left anterior descending artery, as well as a 30%–50% stenosis of the mid-distal right coronary artery. Revascularisation was deferred and antiplatelet as well as heart failure therapy begun. A repeat TTE 6 days later revealed a quasi-normalised LVEF. Ultimately, percutaneous coronary revascularisation of the left main and left anterior descending artery was performed, with favourable outcome at 6-month follow-up.
Isolated optic neuropathy due to folate deficiency with associated iron overload
Authors: Pique Karina , Taber William , Thompson Anthony , Maitland Charles Gerry
Published: July 2021

Isolated optic neuropathy due to folate deficiency is rarely reported. Poor dietary practices, malabsorption, and tobacco/alcohol abuse are usually responsible. We examined a patient with blinding optic neuropathies and isolated folic acid deficiency. Visual acuity recovered after folate replacement. At the same time, serological investigation revealed high ferritin and iron saturation levels with negative genetic markers for haemochromatosis consistent with the diagnosis of iron overload syndrome. There are no reports of blindness associated with iron overload syndrome.
RecurrentCutibacterium acnesprosthetic valve endocarditis
Authors: Abdelhamid Ahmed Ashraf , Kobayashi Takaaki , Tholany Joseph , Sekar Poorani
Published: July 2021

A 29-year-old man with a history of congenital aortic stenosis and mechanical aortic valve replacement with previousCutibacterium acnesprosthetic valve endocarditis (PVE) presented with a 2-week history of fevers and night sweats. Transoesophageal echocardiogram revealed a 0.6 cm×0.5 cm vegetation on the mechanical aortic valve. An anaerobic blood culture became positive forC. acnes6 days after the blood cultures were obtained. He did not have any surgical intervention. He was successfully treated with 6 weeks of ceftriaxone, followed by chronic suppression with oral doxycycline. Despite its low virulence, a growing number ofC. acnesPVE cases have been reported, owing to its biofilm production. When clinical suspicion is high, extending culture incubation duration beyond the standard 5 days might be helpful. Most cases are treated with surgical repair or replacement in conjunction with antibiotics, but medical therapy alone has been documented as being successful.
Multisystem inflammatory syndrome in an adult following the SARS-CoV-2 vaccine (MIS-V)
Authors: Nune Arvind , Iyengar Karthikeyan P , Goddard Christopher , Ahmed Ashar E
Published: July 2021

SARS-CoV-2 vaccine roll-out has been successful in the UK and other parts of the world; however, there are increasing concerns about adverse events. A 44-year-old woman presented to a UK hospital with left upper arm pain at the vaccine site a couple of days after receiving the Pfizer-BioNTech mRNA vaccine, which progressed to fever, diarrhoea and abdominal pain over the next few days. She had an erythematous rash on the chest with subcutaneous oedema. Her C reactive protein was 539 mg/L, white cell count of 17×109/L (1.8–7.5), troponin-T of 1013 ng/L and creatine kinase of 572 u/L. She developed an unprovoked pulmonary embolism with acute kidney injury. After administration of intravenous methylprednisolone, the muscle oedema, skin rashes and acute kidney injury resolved. Although multisystem inflammatory syndrome (MIS) is described in children (MIS-C) and adults (MIS-A) following SARS-CoV-2 infection, we highlight the first reported MIS-V case after the SARS-CoV-2 vaccine.
Cerebral air embolism after indwelling pleural catheter insertion in a chronic hydropneumothorax secondary to epithelioid mesothelioma
Authors: Jayawardena Dissanayake Mudiyanselage Chanaka , Panchal Rakesh K , Agrawal Sanjay , Das Indrajeet
Published: July 2021

A 75-year-old man with a history of epithelioid mesothelioma and a right-sided indwelling pleural catheter (IPC) presented with a history of a purulent fluid drainage via the IPC. The pleural fluid culturedKlebsiella oxytocaandEnterococcus faecalis. He was treated with a course of oral fluoroquinolone followed by uneventful IPC replacement. One and half hours postprocedure, the patient had a witnessed drop in conscious level accompanied by seizure like activity. Acute stroke was suspected and a CT head was performed. CT head revealed multiple serpiginous pockets of air along the cerebral fissure, with features that were highly suggestive of cerebral air embolism and multiple wedge-shaped areas of infarction involving the cerebral hemispheres. Further imaging revealed satisfactory position of the replaced IPC. The patient was admitted to the intensive care unit for high flow oxygen therapy and head down ventilation. However, his condition deteriorated and he died later.
Preliminary results of clinical use of colchicine in COVID-19 treatment
Authors: Knack Rafael Silvestre , Losso Luis Carlos , Knack Renata Silvestre , Hanada Talie
Published: July 2021

We report a case of the use of colchicine in a patient infected with SARS-CoV-2 virus. A 37-year-old man with COVID-19 presented with moderate symptoms, mild pulmonary impairment and elevated inflammatory markers, suggesting an increased risk of cytokine storm and possible worsening of clinical condition. Experimental use of colchicine resulted in an 85% decrease in C reactive protein levels 3 days after treatment initiation and a 182.6% decrease in interleukin-6 levels 8 days after treatment initiation. Due to the lack of effective therapies, it is important to search for potential compounds and compounds that focus on controlling the danger caused by systemic inflammation in COVID-19. Although further research is needed in the area of colchicine and viral infection, preliminary efficacy was observed.
Rhegmatogenous retinal detachment presentation and surgery in uveitic eyes
Authors: Young-Zvandasara Tafadzwa , Brunner David , Welch Sarah , Sims Joanne L , De Souza Clairton , Cunningham William J , Niederer Rachael L
Published: July 2021

Background/aims

To explore the occurrence, uveitis activity, features, rate of proliferative vitreoretinopathy (PVR) and outcomes following rhegmatogenous retinal detachment (RRD) in a large tertiary referral uveitis service.

Methods

Retrospective analysis of subjects attending between 2008 and 2019. Multivariate analysis of risk factors for RRD was calculated. Nelson-Aalen plots were used to demonstrate cumulative risk of RRD. Outcomes of RRD surgery and prognostic indicators were analysed.

Results

Two thousand four hundred and forty-seven (2447) subjects (3516 eyes) with uveitis included. The mean follow-up was 5.7 years (19 767 eye-years); 56 eyes developed a RRD (1.6%). Thirty-two eyes had surgery in our unit. Risk factors for RRD were posterior uveitis or panuveitis (HR 3.386, p<0.001), male gender (HR 2.045, p=0.029) and infectious aetiology (HR 1.942, p=0.044). PVR was present in six (18.8%) eyes at presentation, and a further four (12.5%) developed it after the primary surgery. Final follow-up data showed 16 (50%) moderate or severe visual loss, although 29 (90.6%) had anatomical reattachment without oil in situ.

Conclusions

There is a high rate of RRD in uveitis eyes. This is accompanied by high rates of PVR and redetachment. Anatomical success was high, but visual outcomes remain unpredictable.
Optimal resection rate for lung cancer in the UK: how high should we go?
Authors: Belcher Elizabeth , Mitchell Jenny , Stavroulias Dionisios , Di Chiara Francesco , Rahman Najib
Published: July 2021

Background

The optimal resection rate for institutions managing early-stage primary lung cancer is not known. Whether the prognosis of patients who do not proceed to operation is determined by their comorbidities for which they were deemed at prohibitively high-operative risk, or disease progression, is uncertain. We investigated the outcomes of patients with early-stage lung cancer who were considered for surgical management.

Methods

We reviewed the outcomes of consecutive patients who were considered for resection of early-stage primary lung cancer at Oxford University Hospitals National Health Service Foundation Trust between 2012 and 2017.

Results

Between 29 November 2012 and 31 March 2017, 467 consecutive patients underwent resection with curative intent for primary lung cancer (operative group), while 81 patients were deemed resectable but either inoperable or did not wish to proceed to operation (non-operative group). Reason for not proceeding to resection was cardiovascular in 16 patients (19.8%), respiratory in 21 (25.9%), cardiorespiratory in 11 (13.6%), performance status in 8 (9.9%) and patient choice in 25 (30.9%) patients. Sixty-six patients (81.5%) received an alternative radical treatment. Median follow-up was 169 weeks (IQR 119–246 weeks) in the operative group and 118 weeks (IQR 74–167 weeks) in the non-operative group. Median survival of patients with early-stage lung cancer who did not proceed to operation was 2.5 years; median survival of patients undergoing lung cancer resection was undefined (p<0.0001). Lung cancer was documented as directly or indirectly leading to or contributing to death in 40 patients (76.9%). In 11 patients, the cause of death was due to comorbidities (21.2%).

Conclusions

Patients turned down for operation in a high-resection rate UK unit have limited survival due to lung cancer progression. We conclude that ‘optimal’ resection rates may not have been reached in the UK even in high-resection rate centres.
Characteristics of pulmonary cryptococcosis in patients with rheumatoid arthritis
Authors: Hosoda Chiaki , Ishiguro Takashi , Uozumi Ryuji , Ueda Miyuki , Takata Naomi , Takayanagi Noboru
Published: July 2021

Background and objective

A high frequency of infections complicating rheumatoid arthritis (RA) has been reported due to the immunomodulatory effect of RA or to agents with immunosuppressive effects used in its treatment. We aimed to assess clinical and radiological characteristics of pulmonary cryptococcosis in patients with and without RA.

Methods

We retrospectively reviewed the medical records of 52 patients with pulmonary cryptococcosis and divided them into two groups, those with RA and without RA, and compared clinical characteristics and radiological findings between them.

Results

Eleven (21.2%) of the 52 patients had RA. Median follow-up periods were 51.2 (range: 1.1–258.7) months for patients with RA and 19.1 (range: 0.63–246.9) months for patients without RA. Among the patients with RA, 81.8% were women, with a mean age of 68.1 years. Female sex and respiratory comorbidities were significantly more frequent in patients with RA than in patients without RA. Frequencies of concomitant cryptococcal meningitis and respiratory failure were not different between the groups. There were no significant differences in frequency of any radiological findings, locations and number between the two groups. Among patients with RA, all but one responded well to antifungal treatment. During the antifungal treatment course, one (9.1%) patient with RA died of cryptococcosis. Despite continuing antirheumatic drugs, no patients had recurrence of pulmonary cryptococcosis during follow-up.

Conclusion

Other than some differences in background, there were no clinical, radiological or prognostic differences between the patients with and without RA with pulmonary cryptococcosis. The administration of antirheumatic therapy had no negative effect on the clinical course of antifungal treatment.
Efficacy and safety of high flow nasal oxygen for children with bronchiolitis: systematic review and meta-analysis
Authors: Dafydd Carwyn , Saunders Benjamin J , Kotecha Sarah J , Edwards Martin O
Published: July 2021

Background

To assess the published evidence to establish the efficacy and safety of high flow oxygen cannula (HFNC) as respiratory support for children up to 24 months of age with bronchiolitis within acute hospital settings.

Methods

We searched eight databases up to March 2021. Studies including children up to 24 months of age with a diagnosis of bronchiolitis recruited to an randomised controlled trial were considered in the full meta-analysis. At least one arm of the study must include HFNC as respiratory support and report at least one of the outcomes of interest. Studies were identified and extracted by two reviewers. Data were analysed using Review Manager V.5.4.

Results

From 2943 article titles, 308 full articles were screened for inclusion. 23 studies met the inclusion criteria, 15 were included in the metanalyses. Four studies reported on treatment failure rates when comparing HFNC to standard oxygen therapy (SOT). Data suggests HFNC is superior to SOT (OR 0.45, 95% CI 0.36 to 0.57). Four studies reported on treatment failure rates when comparing HFNC to continuous positive airways pressure (CPAP). No significant difference was found between CPAP and HFNC (OR 1.64, 95% CI 0.96 to 2.79; p=0.07). Four studies report on adverse outcomes when comparing HFNC to SOT. No significant difference was found between HFNC & SOT (OR 1.47, 95% CI 0.54 to 3.99).

Conclusion

HFNC is superior to SOT in terms of treatment failure and there is no significant difference between HFNC and CPAP in terms of treatment failure. The results suggest HFNC is safe to use in acute hospital settings.
Weight management and determinants of weight change in patients with coronary artery disease
Authors: Tijssen Arno , Snaterse Marjolein , Minneboo Madelon , Lachman Sangeeta , Scholte op Reimer Wilma , Peters Ron J , Jørstad Harald Thune
Published: July 2021

Objective

To study the effects of a comprehensive secondary prevention programme on weight loss and to identify determinants of weight change in patients with coronary artery disease (CAD).

Methods

We performed a secondary analysis focusing on the subgroup of overweight CAD patients (BMI ≥27 kg/m2) in the Randomised Evaluation of Secondary Prevention by Outpatient Nurse SpEcialists-2 (RESPONSE-2) multicentre randomised trial. We evaluated weight change from baseline to 12-month follow-up; multivariable logistic regression with backward elimination was used to identify determinants of weight change.

Results

Intervention patients (n=280) lost significantly more weight than control patients (n=257) (−2.4±7.1 kg vs −0.2±4.6 kg; p<0.001). Individual weight change varied widely, with weight gain (≥1.0 kg) occurring in 36% of interventions versus 41% controls (p=0.21). In the intervention group, weight loss of ≥5% was associated with higher age (OR 2.94), lower educational level (OR 1.91), non-smoking status (OR 2.92), motivation to start with weight loss directly after the baseline visit (OR 2.31) and weight loss programme participation (OR 3.33), whereas weight gain (≥1 kg) was associated with smoking cessation ≤6 months before or during hospitalisation (OR 3.21), non-Caucasian ethnicity (OR 2.77), smoking at baseline (OR 2.70), lower age (<65 years) (OR 1.47) and weight loss programme participation (OR 0.59).

Conclusion

The comprehensive secondary prevention programme was, on average, effective in achieving weight loss. However, wide variation was observed. As weight gain was observed in over one in three participants in both groups, prevention of weight gain may be as important as attempts to lose weight.

Trial registration number

NTR3937.
Type 2 diabetes mellitus and antibiotic-resistant infections: a systematic review and meta-analysis
Authors: Carrillo-Larco Rodrigo M , Anza-Ramírez Cecilia , Saal-Zapata Giancarlo , Villarreal-Zegarra David , Zafra-Tanaka Jessica Hanae , Ugarte-Gil Cesar , Bernabé-Ortiz Antonio
Published: July 2021

Background

Type 2 diabetes mellitus (T2DM) has been associated with infectious diseases; however, whether T2DM is associated with bacterial-resistant infections has not been thoroughly studied. We ascertained whether people with T2DM were more likely to experience resistant infections in comparison to T2DM-free individuals.

Methods

Systematic review and random-effects meta-analysis. The search was conducted in Medline, Embase and Global Health. We selected observational studies in which the outcome was resistant infections (any site), and the exposure was T2DM. We studied adult subjects who could have been selected from population-based or hospital-based studies. I2was the metric of heterogeneity. We used the Newcastle-Ottawa risk of bias scale.

Results

The search retrieved 3370 reports, 97 were studied in detail and 61 (449 247 subjects) were selected. Studies were mostly cross-sectional or case–control; several infection sites were studied, but mostly urinary tract and respiratory infections. The random-effects meta-analysis revealed that people with T2DM were twofold more likely to have urinary tract (OR=2.42; 95% CI 1.83 to 3.20; I219.1%) or respiratory (OR=2.35; 95% CI 1.49 to 3.69; I258.1%) resistant infections. Although evidence for other infection sites was heterogeneous, they consistently suggested that T2DM was associated with resistant infections.

Conclusions

Compelling evidence suggests that people with T2DM are more likely to experience antibiotic-resistant urinary tract and respiratory infections. The evidence for other infection sites was less conclusive but pointed to the same overall conclusion. These results could guide empirical treatment for patients with T2DM and infections.
Src/lck inhibitor dasatinib reversibly switches off cytokine release and T cell cytotoxicity following stimulation with T cell bispecific antibodies
Authors: Leclercq Gabrielle , Haegel Hélène , Schneider Anneliese , Giusti Anna Maria , Marrer-Berger Estelle , Boetsch Christophe , Walz Antje-Christine , Pulko Vesna , Sam Johannes , Challier John , Ferlini Cristiano , Odermatt Alex , Umaña Pablo , Bacac Marina , Klein Christian
Published: July 2021

Background

T cell engagers are bispecific antibodies recognizing, with one moiety, the CD3ε chain of the T cell receptor and, with the other moiety, specific tumor surface antigens. Crosslinking of CD3 upon simultaneous binding to tumor antigens triggers T cell activation, proliferation and cytokine release, leading to tumor cell killing. Treatment with T cell engagers can be associated with safety liabilities due to on-target on-tumor, on-target off-tumor cytotoxic activity and cytokine release syndrome (CRS). Tyrosine kinases such as SRC, LCK or ZAP70 are involved in downstream signaling pathways after engagement of the T cell receptor and blocking these kinases might serve to abrogate T cell activation when required (online supplemental material 1). Dasatinib was previously identified as a potent kinase inhibitor that switches off CAR T cell functionality.

Methods

Using an in vitro model of target cell killing by human peripheral blood mononuclear cells, we assessed the effects of dasatinib combined with 2+1 T cell bispecific antibodies (TCBs) including CEA-TCB, CD19-TCB or HLA-A2 WT1-TCB on T cell activation, proliferation and target cell killing measured by flow cytometry and cytokine release measured by Luminex. To determine the effective dose of dasatinib, the Incucyte system was used to monitor the kinetics of TCB-mediated target cell killing in the presence of escalating concentrations of dasatinib. Last, the effects of dasatinib were evaluated in vivo in humanized NSG mice co-treated with CD19-TCB. The count of CD20+ blood B cells was used as a readout of efficacy of TCB-mediated killing and cytokine levels were measured in the serum.

Results

Dasatinib concentrations above 50 nM prevented cytokine release and switched off-target cell killing, which were subsequently restored on removal of dasatinib. In addition, dasatinib prevented CD19-TCB-mediated B cell depletion in humanized NSG mice. These data confirm that dasatinib can act as a rapid and reversible on/off switch for activated T cells at pharmacologically relevant doses as they are applied in patients according to the label.

Conclusion

Taken together, we provide evidence for the use of dasatinib as a pharmacological on/off switch to mitigate off-tumor toxicities or CRS by T cell bispecific antibodies.