bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and Fabrication of a Silicon-Based MEMS Rotary Engine
Authors: Fu Kelvin , Knobloch Aaron J. , Martinez Fabian C. , Walther David C. , Fernandez-Pello Carlos , Pisano Al P. , Liepmann Dorian 
Published: November 2021

Abstract
Design and fabrication of a Silicon-based MEMS rotary engine are discussed in this paper. This work is part of an effort currently underway to develop a portable, autonomous power generation system potentially capable of having an order of magnitude improvement in energy density over alkaline or lithium-ion batteries. Central to the development of this power generation system are small-scale rotary internal combustion engines fueled by high energy density liquid hydrocarbons capable of delivering power on the order of milli-Watts. The rotary (Wankel-type) engine is well suited for MEMS fabrication due to its planar geometry, high specific power, and self-valving operation with a minimal number of moving parts. The smallest “micro-rotary” engine currently being fabricated has an epitrochoidal-shaped housing under 1 mm3 in size and with a rotor swept volume of 0.08 mm3.
This paper discusses some of the fabrication issues unique to MEMS fabrication of a rotary engine at this small scale. High precision, high aspect ratio structures are necessary to provide adequate sealing for high compression ratios. Effects such as footing and lateral to vertical etch rates must be minimized for proper engine operation. A fabrication process is necessary for the complex, multi-height geometry of the housing and rotor assembly. Finally, a repeatable and simple assembly technique must be developed in order to mass-produce these engines.
Fabrication of a Silicon-based micro-rotary engine is being conducted in U.C. Berkeley’s Microfabrication Laboratory. The engine system is composed of three main components: rotor, housing, and shaft. The engine and rotor housing must be entirely fabricated from Silicon without embedded oxide to prevent thermal mismatch or structural weakness at the Si-oxide interface. In order to meet this requirement, the fabrication processes for the housing consists of a two-mask two-etch process of a solid Silicon wafer. The fabrication of the rotor follows a similar process, utilizing deposited oxide as a release layer. Using Silicon Dioxide and photoresist for masking, housing and rotor structures are etched from solid Silicon using timed Deep Reactive Ion Etching (DRIE). A unique feature of these processes is the self-masking of the spur gear in the housing and the shaft thru hole in the rotor during the second DRIE steps, which give the necessary multi-level, cross-sectional profile.
Boundary Layer Analysis of Acoustic Diffraction by a Half-Plane in a Viscous Fluid Medium
Authors: Nagem Raymond J. , Sandri Guido 
Published: November 2021

Abstract
We investigate the effects of fluid viscosity on the diffraction of a time-harmonic acoustic plane wave by a semi-infinite half-plane. A boundary layer approximation based on a multiple scale expansion and the known inviscid diffraction solution is used to derive the velocity field near the surface of the half-plane. The boundary layer approximation is compared to an independent incompressible viscous flow solution that is derived for a small circular region in the neighborhood of the edge of the half-plane.
Rhythm and Reaching: The Influence of Rhythmic Auditory Cueing in a Goal-Directed Reaching Task With Adults Diagnosed With Cerebral Palsy
Authors: Ladwig Jacqueline C. , do Prado Tamires C. , Tomy Stephanie J. , Marotta Jonathan J. , Glazebrook Cheryl M. 
Published: November 2021

Improvements in functional reaching directly support improvements in independence. The addition of auditory inputs (e.g., music, rhythmic counting) may improve goal-directed reaching for individuals with cerebral palsy (CP). To effectively integrate auditory stimuli into adapted teaching and rehabilitation protocols, it is necessary to understand how auditory stimuli may enhance limb control. This study considered the influence of auditory stimuli during the planning or execution phases of goal-directed reaches. Adults (with CP = 10, without CP = 10) reached from a home switch to two targets. Three conditions were presented—no sound, sound before, and sound during—and three-dimensional movement trajectories were recorded. Reaction times were shorter for both groups in the sound before condition, while the group with CP also reached peak velocity relatively earlier in the sound before condition. The group with CP executed more consistent movements in both sound conditions. Sound presented before movement initiation improved both the planning and execution of reaching movements for adults with CP.
Treating nontuberculous mycobacteria in children with cystic fibrosis: a multicentre retrospective study
Authors: Saint Gemma L , Thomas Matthew F , Zainal Abidin Noreen , Langley Ross John , Brodlie Malcolm , McNamara Paul 
Published: November 2021

BackgroundRespiratory infection with nontuberculous mycobacteria (NTM) in children with cystic fibrosis (CF) has increased in prevalence. The condition is difficult to diagnose and treatments are complex with limited evidence to guide practice. This study describes the approaches to diagnosis, management and consequences of treatment in a multicentre cohort of children with CF in the UK.MethodsRetrospective data were collected from 11 CF specialist centres from patients less than 17 years old, treated for NTM infection between 2006 and 2017. Descriptive statistics were used to describe the clinical characteristics of children treated. Treatment regimens, adverse events and success of treatment, with respect to lung function and culture conversion, were evaluated.ResultsData from 70 patients treated for NTM pulmonary disease were collated (60 Mycobacterium abscessus complex (MABSC); 10 M. avium complex (MAC)). Older age and previous diagnosis of allergic bronchopulmonary aspergillosis were all significantly associated with NTM. There was a wide variance in drug choice and side effects were reported with all agents. NTM eradication occurred in 80% of patients with MAC and 48% with MABSC, with variable outcomes on lung function.ConclusionsDiagnosis and treatment of NTM infection in children with CF is challenging. Treatment success is not guaranteed, particularly for MABSC. Large clinical trials are urgently required to evaluate treatment regimes and their suitability and efficacy in children.
Ocular and systemic determinants of perifoveal and macular vessel parameters in healthy African Americans
Authors: Richter Grace M , Lee Jae Chang , Khan Nasir , Vorperian Alexander , Hand Brennan , Burkemper Bruce , Zhou Xiao , Chu Zhongdi , Wang Ruikang , Varma Rohit , Kashani Amir H 
Published: November 2021

PurposeTo determine the relationship of various systemic and ocular characteristics with perifoveal and macular vessel density in healthy African American eyes.DesignA population-based cross-sectional study of prospectively recruited African Americans ≥40 years of age. Participants underwent 3×3 mm and 6×6 mm macula scans using spectral-domain optical coherence tomography angiography (OCTA), clinical examinations and clinical questionnaires. Participants with glaucoma, severe non-proliferative diabetic retinopathy, proliferative diabetic retinopathy and macular oedema were excluded. Custom MATLAB based software quantified vessel area density (VAD) and vessel skeleton density (VSD) in the superficial retinal layer of the macula. Multivariable regression analysis, controlling for inter-eye correlation, was performed to determine systemic and ocular determinants of macular vessel metrics using stepwise selection. Candidate variables included: age, gender, body mass index, history of smoking, history of diabetes, diabetes duration, history of stroke or brain haemorrhage, systolic blood pressure, diastolic blood pressure (DBP), pulse pressure, mean arterial pressure, central subfield thickness (CSFT), visual field mean deviation, intraocular pressure, axial length (AL), mean ocular perfusion pressure and signal strength (SS).ResultsA total of 2221 OCTA imaged eyes from 1472 participants were included in this study. Reduced perifoveal and macular VAD and VSD were independently associated with longer AL, reduced SS, reduced CSFT and older age. Male gender and lower DBP were also associated with reduced perifoveal and macular VSD.ConclusionsWhen interpreting OCTA images in a clinical setting, it is important to consider the effects ocular and systemic characteristics may have on the macular microcirculation.
Economic impacts of overweight and obesity: current and future estimates for eight countries
Authors: Okunogbe Adeyemi , Nugent Rachel , Spencer Garrison , Ralston Johanna , Wilding John 
Published: November 2021

BackgroundObesity is a growing public health challenge worldwide with significant health and economic impacts. However, much of what is known about the economic impacts of obesity comes from high-income countries and studies are not readily comparable due to methodological differences. Our objective is to demonstrate a method for estimating current and future national economic impacts of obesity and apply it across a sample of heterogeneous contexts globally.MethodsWe estimated economic impacts of overweight and obesity for eight countries using a cost-of-illness approach. Direct and indirect costs of obesity from 2019 to 2060 were estimated from a societal perspective as well as the effect of two hypothetical scenarios of obesity prevalence projections. Country-specific data were sourced from published studies and global databases.ResultsIn per capita terms, costs of obesity in 2019 ranged from US$17 in India to US$940 in Australia. These economic costs are comparable to 1.8% of gross domestic product (GDP) on average across the eight countries, ranging from 0.8% of GDP in India to 2.4% in Saudi Arabia. By 2060, with no significant changes to the status quo, the economic impacts from obesity are projected to grow to 3.6% of GDP on average ranging from 2.4% of GDP in Spain to 4.9% of GDP in Thailand. Reducing obesity prevalence by 5% from projected levels or keeping it at 2019 levels will translate into an average annual reduction of 5.2% and 13.2% in economic costs, respectively, between 2020 and 2060 across the eight countries.ConclusionOur findings demonstrate that the economic impacts of obesity are substantial across countries, irrespective of economic or geographical context and will increase over time if current trends continue. These findings strongly point to the need for advocacy to increase awareness of the societal impacts of obesity, and for policy actions to address the systemic roots of obesity.
Association between serum soluble fms-like tyrosine kinase-1 and the central choroidal thickness during pregnancy: a prospective study
Authors: Suzuki Takafumi , Inoue Tatsuya , Igarashi Nozomi , Agata Chisato , Okubo Atsushi , Nagamatsu Takeshi , Iriyama Takayuki , Maruyama-Inoue Maiko , Yanagi Yasuo , Kadonosono Kazuaki , Asaoka Ryo , Azuma Keiko , Obata Ryo 
Published: November 2021

ObjectiveTo investigate the association between serum soluble fms-like tyrosine kinase-1 (sFlt-1) and the choroidal structure during the pregnancy.Methods and analysisThis prospective study enrolled 24 eyes of 12 consecutive healthy pregnant women. Each participant was evaluated during the first, second and third trimester of pregnancy and the postpartum period. The central choroidal thickness (CCT) and Choroidal Vascular Index (CVI) were measured using enhanced depth-imaging optical coherence tomography. Moreover, serum sFlt-1 and vascular endothelial growth factor (VEGF) concentrations were measured manually using ELISA. The association between choroidal structural parameters and serum sFlt-1/VEGF was analysed using a linear mixed model.ResultsThe CCT was significantly thicker in the second and third trimester than the postpartum period (p<0.05). In contrast, there was no significant difference in the CVI throughout pregnancy or the postpartum period. Serum sFlt-1 levels were significantly higher during pregnancy than the postpartum period (p<0.05), whereas the serum VEGF levels were significantly lower during pregnancy than the postpartum period (p<0.05). Furthermore, serum sFlt-1 levels were significantly associated with CCT throughout pregnancy (p=0.011, linear mixed model). On the contrary, sFlt-1 levels was not associated with the CVI during the pregnancy.ConclusionOur results suggest that serum sFlt-1 might have an influence on the choroidal thickness during the pregnancy.
Differences in the thermal properties and surface temperature of prehospital antihypothermia devices: an in vitro study
Authors: Dvir Erez , Epstein Danny , Berzon Baruch , Raz Aeyal , Lehavi Amit 
Published: November 2021

BackgroundPreventing and treating hypothermia in prehospital settings is crucial. Several products have been developed to prevent heat loss and actively warm patients in prehospital settings. We compared the efficacy and the surface temperature of different antihypothermia products, using a fluid-based model at two ambient temperatures.MethodsWe tested five active (Blizzard Heat with active pads, Ready-Heat, Ready-Heat-II, Hypothermia Prevention and Management Kit (HPMK), Bair Hugger) and five passive (Blizzard Heat, Heat Reflective Shell, sleeping bag, ‘space blanket’, wool blanket) antihypothermia products. A torso model consisting of four 8 L bags of fluid preheated to 36°C±0.5°C (97±0.5°F) was used to compare the devices’ performances at 20°C (68°F) and 8°C (46°F). Inner and surface temperatures were recorded for up to 480 min.ResultsWe found significant differences in heat loss in fluid bags among the tested devices at both temperatures (p<0.001). At 20°C, only HPMK and Ready-Heat-II increased the inner temperature for 480 min while Blizzard Heat with active pads prevented heat loss. Ready-Heat prevented heat loss for 90 min. All the other devices did not prevent heat loss beyond 30 min. At 8°C, none of the products heated the model. Bair Hugger, HPMK, Ready-Heat II and sleeping bag prevented heat loss for 30 min. At 60, 90 and 120 min HPMK, Ready-Heat II and Bair Hugger were the most effective. Over 480 min, Bair Hugger was most effective, with a heat loss of 2.3°C±0.4°C. The surface temperature exceeded 44°C (111°F) for all the exothermic warming devices when used for a prolonged period of time.ConclusionAt 20°C, HPMK and Ready-Heat-II increased fluid temperature in the model, while the other devices decreased heat loss. At 8°C, none of the tested devices increased the temperature. However, active heating devices prevented heat loss slightly better than passive methods. A protective insulation layer should be used with all active heating blankets.
What predicts poor outcome after successful thrombectomy in early time window?
Authors: Olivot Jean-Marc , Heit Jeremy J , Mazighi Mikael , Raposo Nicolas , Albucher Jean François , Rousseau Vanessa , Guenego Adrien , Thalamas Claire , Mlynash Michael , Drif Amel , Christensen Soren , Sommet Agnes , Viguier Alain , Darcourt Jean , Januel Anne-Christine , Calviere Lionel , Menegon Patrice , Caparros François , Bonneville Fabrice , Tourdias Thomas , Sibon Igor , Albers Gregory W , Cognard Christophe 
Published: November 2021

BackgroundHalf of the patients with large vessel occlusion (LVO)-related acute ischemic stroke (AIS) who undergo endovascular reperfusion are dead or dependent at 3 months. We hypothesize that in addition to established prognostic factors, baseline imaging profile predicts outcome among reperfusers.MethodsConsecutive patients receiving endovascular treatment (EVT) within 6 hours after onset with Thrombolysis In Cerebral Infarction (TICI) 2b, 2c and 3 revascularization were included. Poor outcome was defined by a modified Rankin scale (mRS) 3–6 at 90 days. No mismatch (NoMM) profile was defined as a mismatch (MM) ratio ≤1.2 and/or a volume <10 mL on pretreatment imaging.Results187 patients were included, and 81 (43%) had a poor outcome. Median delay from stroke onset to the end of EVT was 259 min (IQR 209–340). After multivariable logistic regression analysis, older age (OR 1.26, 95% CI 1.06 to 1.5; p=0.01), higher National Institutes of Health Stroke Scale (NIHSS) (OR 1.15, 95% CI 1.06 to 1.25; p<0.0001), internal carotid artery (ICA) occlusion (OR 3.02, 95% CI 1.2 to 8.0; p=0.021), and NoMM (OR 4.87, 95% CI 1.09 to 22.8; p=0.004) were associated with poor outcome. In addition, post-EVT hemorrhage (OR 3.64, 95% CI 1.5 to 9.1; p=0.04) was also associated with poor outcome.ConclusionsThe absence of a penumbra defined by a NoMM profile on baseline imaging appears to be an independent predictor of poor outcome after reperfusion. Strategies aiming to preserve the penumbra may be encouraged to improve these patients’ outcomes.
Distribution of symptomatic cerebral vasospasm following subarachnoid hemorrhage assessed using cone-beam CT angiography
Authors: Simonato Davide , Borchert Robin Jacob , Vallee Fabrice , Joachim Jona , Civelli Vittorio , Cancian Luca , Houdart Emmanuel , Labeyrie Marc-Antoine 
Published: November 2021

Background and purposeCone-beam CT angiography (CB-CTA) provides a three-dimensional spatial resolution which is, so far, unmatched in clinical practice compared with other conventional techniques such as two-dimensional digital subtracted angiography. We aimed to assess the distribution of symptomatic cerebral vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) using CB-CTA.Methods30 consecutive patients with aSAH undergoing vasospasm percutaneous balloon angioplasty (PBA) were recruited and underwent CB-CTA in this single-center prospective cohort series. Intracranial arteries were systematically analyzed by two independent observers from the large trunks to the distal cortical branches and perforators using a high-resolution reconstruction protocol. Intermediate and severe cerebral vasospasm was defined as 30–50% and >50% narrowing in the diameter of the vessel, respectively.Results35 arterial cervical artery territories were analyzed, of which 80% were associated with clinical or radiological signs of delayed cerebral ischemia. The median spatial resolution was 150 µm (range 100–250 µm). Intermediate or severe vasospasm was observed in the proximal (86%, 95% CI 74% to 97%), middle (89%, 95% CI 78% to 99%), and distal (60%, 95% CI 44% to 76%) segments of the large trunks, as well as the cortical branches (11%, 95% CI 1% to 22%). No vasospasm was observed in basal ganglia or cortical perforators, or in arteries smaller than 900 µm. Vasospasm was more severe in middle or distal segments compared with proximal segments in 43% (95% CI 26% to 59%) of cases.ConclusionsOur study demonstrated that symptomatic cerebral vasospasm following aSAH did not involve arteries smaller than 900 µm, and frequently predominated in middle or distal segments. These results offer new insights into the potential management options for vasospasm using PBA.
Aerosol emission from the respiratory tract: an analysis of aerosol generation from oxygen delivery systems
Authors: Hamilton Fergus W , Gregson Florence K A , Arnold David T , Sheikh Sadiyah , Ward Kirsty , Brown Jules , Moran Ed , White Carrie , Morley Anna J ,   AERATOR Group, Bzdek Bryan R , Reid Jonathan P , Maskell Nicholas A , Dodd James William 
Published: November 2021

Introductioncontinuous positive airway pressure (CPAP) and high-flow nasal oxygen (HFNO) provide enhanced oxygen delivery and respiratory support for patients with severe COVID-19. CPAP and HFNO are currently designated as aerosol-generating procedures despite limited high-quality experimental data. We aimed to characterise aerosol emission from HFNO and CPAP and compare with breathing, speaking and coughing.Materials and methodsHealthy volunteers were recruited to breathe, speak and cough in ultra-clean, laminar flow theatres followed by using CPAP and HFNO. Aerosol emission was measured using two discrete methodologies, simultaneously. Hospitalised patients with COVID-19 had cough recorded using the same methodology on the infectious diseases ward.ResultsIn healthy volunteers (n=25 subjects; 531 measures), CPAP (with exhalation port filter) produced less aerosol than breathing, speaking and coughing (even with large >50 L/min face mask leaks). Coughing was associated with the highest aerosol emissions of any recorded activity. HFNO was associated with aerosol emission, however, this was from the machine. Generated particles were small (<1 µm), passing from the machine through the patient and to the detector without coalescence with respiratory aerosol, thereby unlikely to carry viral particles. More aerosol was generated in cough from patients with COVID-19 (n=8) than volunteers.ConclusionsIn healthy volunteers, standard non-humidified CPAP is associated with less aerosol emission than breathing, speaking or coughing. Aerosol emission from the respiratory tract does not appear to be increased by HFNO. Although direct comparisons are complex, cough appears to be the main aerosol-generating risk out of all measured activities.
Evidence of dispersal between the Yenisei and the Lena river basins during the late Pleistocene within the whitefish (Coregonus lavaretus pidschian) complex
Authors: Bochkarev Nickolay A. , Zuykova Elena I. , Katokhin Alexey V. , Andree Karl B. , Solovyev Mikhail M. 
Published: November 2021

The Coregonus lavaretus (Linnaeus, 1758) complex is a morphologically and genetically diverse group of whitefish. Its taxonomic structure has been controversial for almost a century. At least 25 forms of C. lavaretus have been described in Siberia, but there is still no consensus on their intraspecific structure and taxonomy. Coregonus lavaretus pidschian (Gmelin, 1789) was described as a subspecies of C. lavaretus. Recently, it was assumed that this subspecies is also a complex. The purpose of this study was to compare the distributions of pidschian-like whitefish haplotypes in two basins of large Siberian rivers, Yenisei and Lena, and to assess the gene flow between basins of these rivers, which were connected after the last glaciation. The sequence of the following mitochondrial DNA genes, 16S rRNA (partial), tRNA-Leu (full), NADH dehydrogenase subunit 1 (full), tRNA-Ile (full), and tRNA-Gln (partial), were used for the inference of intraspecific genetic structure of C. l. pidschian. Whitefish haplotypes were clustered into two groups according to their distribution between two large Siberian river basins; however, there were shared haplotypes indicating events of migration and hybridization, which could occur when Bolshoi Yenisei and Lena river systems were connected after the last glaciation (the Late Pleistocene).