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The cooling capacity of a typical dilution refrigerator is mainly determined by the circulating flow of the He-3 in the system, which is usually realized by the external circulation pump. In order to increase the concentration of circulating He-3, the still often take the orifice structure to limit the influence of the superfluid helium film, and this structure will also have a certain impact on the flow rate of He-3. This paper summarizes the flow rate models of each part of the orifice structure, and establishes a model related to the influence of pumping speed and the diameter of orifice on the flow rate of circulating He-3. The relationship between pumping speed and flow rate is developed and the relation is divided into three phases for detailed analysis. It is found that the flow rate and the concentration of circulating He-3 increase first and then decrease with the increasing diameter of orifice at a certain pumping speed, and the possible reasons for this phenomenon are analyzed. The results indicate that there is an optimal orifice diameter at a determined pumping speed. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (CSC) is one of the main disasters in the process of coal mining. In this paper, the important role of high-latent heat phase change material CH3COONa·3H2O (SAT) in controlling CSC was studied and compared with common inhibitors (NaCl, CaCl2, ascorbic acid (VC)). The thermal performance characteristics of SAT were revealed by the C80 micromanometer, and the effects of different inhibitors on the thermal behavior of Shengli lignite were analyzed and compared. Furthermore, the gas–solid coaxial fixed bed measurement system was used in conjunction with the Pfeiffer online mass spectrometer, to design the natural temperature rise experiment of coal after the heating interruption in the same programmed temperature rise interval, investigating the effects of different inhibitors on the temperature and gas production in the process of coal oxidation. The results show that the heat absorption effect of SAT is more significant than common inhibitors, which not only improves the heat absorption rate of the samples but also increases the total heat absorption of the sample by 236.6 J·g−1 compared with the raw coal. In the programmed temperature rise experiment, the maximum temperature point of the SAT-inhibited coal sample is reduced by 15.5% compared with raw coal, the time to reach the maximum temperature point is delayed by 20.5%, and the SAT inhibitor effectively inhibits the production of CO and CO2 gases. The method described in this paper provides a new idea for the prevention and control of CSC. [ABSTRACT FROM AUTHOR]

Introduction: Neutrophils are important participants in the innate immune response. They rapidly and efficiently identify and clear infectious agents by expressing large numbers of membrane receptors. Upon tissue injury or pathogen invasion, neutrophils are the first immune cells to reach the site of injury and participate in the inflammatory response. Materials and methods: A thorough search on PubMed related to neutrophil death or clearance pathways was performed. Conclusion: Inflammatory response and tissue damage can be aggravated when neutrophils are not removed rapidly from the site of injury. Recent studies have shown that neutrophils can be cleared through a variety of pathways, including non-inflammatory and inflammatory death, as well as reverse migration. Non-inflammatory death pathways include apoptosis and autophagy. Inflammatory death pathways include necroptosis, pyroptosis and NETosis. This review highlights the basic properties of neutrophils and the impact of their clearance pathways on the inflammatory response. [ABSTRACT FROM AUTHOR]

Tree lycopsids prospered in the Late Devonian and constituted a major part of the Late Paleozoic forest ecosystem that deeply impacted the Earth's climate. However, the fertile organs of these early tree lycopsids display low morphological disparity, which has hampered further knowledge about their ecological habit. Here, we report Omprelostrobus gigas gen. et sp. nov. from the Upper Devonian (Famennian) Wutong Formation at Changxing, Zhejiang, China. The collection includes aerial axes, strobili and associated roots. The strobili are the largest among coeval lycopsids to our knowledge, and are divided into proximal and distal portions by dimorphic sporophylls with differentiated laminae and probable strong photosynthetic capacity. The associated but not attached roots displaying multiple isotomous branches lack rootlets and typical rootlet scars. The varied strobili sizes of early tree lycopsids were relatively independent of their body plan, but the large strobili could suggest increased reproductive investment to overcome the disadvantages of the disturbed flooded habitat. A new species of Late Devonian fossil lycopsid with large strobili and differentiated sporophylls provides insight into reproductive investment of early tree lycopsids. [ABSTRACT FROM AUTHOR]

Arteriovenous malformation (AVM)-derived ophthalmic artery (OphA) branches are not common, and their management is very challenging. We evaluated the safety and efficacy of Trans OphA ethanol embolotherapy for these lesions. We retrospectively reviewed 26 patients with AVMs fed by OphA, who underwent transOphA embolization using ethanol from February, 2015 to December, 2019. Sixty-six transOphA embolotherapy procedures (range, 1–4 procedures; mean, 2.5 procedures) were performed. Devascularization degree, visual field, visual acuity, and quality-of-life outcomes were compared and analyzed at follow up (mean, 32.6 months; month range 10–60). Complications were recorded. Twenty-five of the 26 patients (96%) reported complete or > 90% AVM devascularization while one patient (4%) showed > 70% devascularization. Eleven patients (42%) presented with visual acuity impairments; among them, 6 had improvements while 4 were completely relieved. Eight patients (30.7%) presented visual field defects, 3 had improvements while 4 were completely relieved. Ten patients (38.4%) presented with diplopia and exophthalmos with 2 being completely relieved while 6 had major improvements. Bleeding was controlled in all cases (100%). All patients (100%) exhibited cosmetic deformities with 17 being completely relieved. Moreover, all patients (100%) exhibited impaired daily life, which was resolved in 21 patients with 5 patients reporting major improvements. After endovascular treatment, there was no vision loss, death, or permanent disability in any patient. TransOphA ethanol embolotherapy is efficacious and safe for symptomatic resolution or improvement of AVMs fed by OphA with acceptable complications without the risk of visual impairment. [ABSTRACT FROM AUTHOR]

Purpose: To summarize a 10-year, single-institution experience with ethanol embolization of nasal arteriovenous malformations (NAVMs) in 52 patients. Patients and methods: The present work was a retrospective study of 52 patients (aged between 1 and 67 years) with NAVMs who were treated with ethanol embolization between August 2009 and August 2019. The diagnosis of NAVMs was established based on clinical and imaging studies including ultrasound, computer tomography angiography, and digital subtract angiography. Embolization techniques used in the current study included transarterial, direct puncture, and a combination of both. The clinical and angiographic features, treatment methods, clinical outcomes, and complications were assessed within the mean period of 55.2 months (range, 1–119 months) after the last embolization. Results: The total number of embolization sessions (140 embolization procedures in 52 pts) included transarterial approach (1 pt), direct puncture (2 pt), and a combination of transarterial and direct puncture (49 pts). There was a positive correlation between nidus size and treatment sessions (r = 0.780, P = 0.0005) and the amount of ethanol injected (r = 0.840, P = 0.0004). Results of the current study showed that the therapeutic outcomes were complete response in two patients (3.8%) without recurrence throughout the follow-up period (range, 1–119 months; mean, 55.2 months), and partial response in 50 patients (96.2%). A total of seven patients (13.5%) experienced one or more complications, including skin necrosis in one patient (1.9%), transient hemoglobinuria in five patients (9.6%), and skin blister in five patients (9.6%). Conclusion: The reported single-institution experience evidently indicated that ethanol embolotherapy has the potential to successfully devascularize NAVMs and also significantly improve symptoms and signs. Further, it was evident that the use of a combination of transarterial and direct puncture techniques has the potential to increase the rate of therapeutic response in patients with NAVMs. [ABSTRACT FROM AUTHOR]

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A heterosporous lycopsid plant is described from the Upper Devonian (Famennian) Wutong Formation, Changxing County, northern Zhejiang Province, China. The plant is known for its terminal and many detached megasporangiate strobili, most of which do not have sporophylls preserved. Some megasporangiate strobili are closely associated with a vegetative axis bearing leaf cushions and with a mass of microspores. Because of the monosporangiate strobili, the present lycopsid belongs to the Dichostrobiles of the Isoёtales sensu lato. This lycopsid conforms to Changxingia in the vegetative leaves, leaf cushions (including leaf scar and ligule pit), some parts of the megasporophyll (pedicel, heel and lamina), the megasporangium and the megaspores, although the branching pattern of axes, the arrangement and other parts of megasporophyll are still unknown. The fossils are described as Changxingia sp., and this genus is expanded with character of microspore. Hence, the previous and present data indicate that the earliest lycopsids with monosporangiate strobili from the Upper Devonian of China are consistent in Lagenicula megaspores with gula and Lycospora microspores with equatorial cingulum. In contrast, the Carboniferous lycopsids with monosporangiate strobili in Euramerica and Cathaysia show great diversification of both megaspores and microspores. [ABSTRACT FROM AUTHOR]

To realize a stable addition of foaming agent used for foam technology, a new adding method using the jet cavitation was introduced, and its performance was investigated experimentally under different operating conditions. Experimental results show that the bubble region in the jet device has a constant vapor pressure, which creates a good condition for liquid absorption, while it shrinks with increasing outlet pressure. The liquid absorption amount keeps unchanged when the outlet pressure is lower than a critical value. The critical outlet pressure increases by 40% with decreasing cavitation absorption amount, which is especially suitable for mini-flow quantitative addition of foaming agent used for foam dust suppression. Its effectiveness on suppressing mine dust was evaluated in a heading face of underground coal mines. Field application indicates that the reliable and simple foaming system adopting the new adding method makes a marked dust suppression effect. The working environment of heading face is significantly improved, ensuring the safe tunneling and personal security. [ABSTRACT FROM AUTHOR]

Objective: Arteriovenous malformations (AVMs) involving the periorbital region are technically challenging clinical entities to manage. The purpose of the present study was to present our initial experience of ethanol embolization in a series of 16 patients with auricular AVMs and assess the outcomes of this treatment.Methods: Transcatheter arterial embolization and/or direct percutaneous puncture embolization were performed in the 16 patients. Pure or diluted ethanol was manually injected. The follow-up evaluations included physical examination and angiography at 1- to 6-month intervals.Results: During the 28 ethanol embolization sessions, the amount of ethanol used ranged from 2 to 65 mL. The obliteration of ulceration, hemorrhage, pain, infection, pulsation, and bruit in most of the patients was obtained. The reduction of redness, swelling, and warmth was achieved in all the 16 patients, with down-staging of the Schobinger status for each patient. AVMs were devascularized 100 % in 3 patients, 76-99 % in 7 patients, and 50-75 % in 6 patients, according to the angiographic findings. The most common complications were necrosis and reversible blister. No permanent visual abnormality was found in any of the cases.Conclusion: Ethanol embolization is efficacious and safe in the treatment of AVMs in the periorbital region and has the potential to be accepted as the primary mode of therapy in the management of these lesions. [ABSTRACT FROM AUTHOR]

A novel composite foam material for blocking air leakage in coal mine was developed. In order to examine the performance of the new composite foam, the foaming property, mechanical property, microstructure, thermal stability, and flame resistance of the composite foams, polyurethane foams, phenolic foams, and urea-formaldehyde foams were investigated. The results show that the composite foam had the biggest compressive strength, thermal stability, and flame resistance. Moreover, composite foam had the lowest foaming temperature and shrinkage, indicating that it had small risk in causing spontaneous combustion of coal, and it exhibited good air leakage blocking effect. Field application showed that composite foam could effectively block air leakage in goaf. Thus, composite foam materials were considered to be the potential candidates for blocking air leakage in coal mines to prevent spontaneous combustion of coal. [ABSTRACT FROM AUTHOR]

For calculating the stiffness function of a structure, the differential equation of the vibration of the structure was divided into the differential equation on the original stiffness function that was known, and Fredholm integral equation of the first kind on the undetermined stiffness function that was unknown. And the stable solutions of the integral equation, when the smooth factor was equal to zero, was solved by the extrapolation with p smooth factors. So the stiffness function of the structure is obtained. Applied examples show that the method is feasible and effective. [ABSTRACT FROM AUTHOR]