Core–sheath polymer nanofiber formation by the simultaneous application of rotation and pressure in a novel purpose-designed vessel

2021 ◽  
Vol 8 (4) ◽  
pp. 041412
Author(s):  
Hussain Alenezi ◽  
Muhammet Emin Cam ◽  
Mohan Edirisinghe
VASA ◽  
2018 ◽  
Vol 47 (3) ◽  
pp. 165-176 ◽  
Author(s):  
Katrin Gebauer ◽  
Holger Reinecke

Abstract. Low-density lipoprotein cholesterol (LDL-C) has been proven to be a causal factor of atherosclerosis and, along with other triggers like inflammation, the most frequent reason for peripheral arterial disease. Moreover, a linear correlation between LDL-C concentration and cardiovascular outcome in high-risk patients could be established during the past century. After the development of statins, numerous randomized trials have shown the superiority for LDL-C reduction and hence the decrease in cardiovascular outcomes including mortality. Over the past decades it became evident that more intense LDL-C lowering, by either the use of highly potent statin supplements or by additional cholesterol absorption inhibitor application, accounted for an even more profound cardiovascular risk reduction. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a serin protease with effect on the LDL receptor cycle leading to its degradation and therefore preventing continuing LDL-C clearance from the blood, is the target of a newly developed monoclonal antibody facilitating astounding LDL-C reduction far below to what has been set as target level by recent ESC/EAS guidelines in management of dyslipidaemias. Large randomized outcome trials including subjects with PAD so far have been able to prove significant and even more intense cardiovascular risk reduction via further LDL-C debasement on top of high-intensity statin medication. Another approach for LDL-C reduction is a silencing interfering RNA muting the translation of PCSK9 intracellularly. Moreover, PCSK9 concentrations are elevated in cells involved in plaque composition, so the potency of intracellular PCSK9 inhibition and therefore prevention or reversal of plaques may provide this mechanism of action on PCSK9 with additional beneficial effects on cells involved in plaque formation. Thus, simultaneous application of statins and PCSK9 inhibitors promise to reduce cardiovascular event burden by both LDL-C reduction and pleiotropic effects of both agents.


The results of studies on the influence of forms and doses of nitrogen fertilizers (ammonium nitrate, urea, carbamide-ammonia mixture, ammonium sulfate) on the productivity of oil flax under the conditions of the western forest-steppe are given. In the traditional system of fertilizer, oil flax is not able to provide high yields and quality products. An effective solution to this is optimization of plant nutrition due to its balance, which promotes intensive plant development, makes it possible to actively and efficiently intervene in the process of harvesting and its quality. Therefore, determining the optimal fertilizer rate for oil flax in specific soil-climatic conditions is important for obtaining stable and high yields of culture. The purpose of our research was to determine the contribution of doses and forms of nitrogen fertilizers to the productivity of flaxseed oil in the soil-climatic conditions of the western forest-steppe. The research was carried out in 2016-2018 at the experimental field of the Institute of Agriculture of the Carpathian region of NAAS in five-point crop rotation with the total area of the plant growing on a gray forest surface glued type of soil In general, four forms of nitrogen fertilizers were studied: ammonia, nitrate, carbamide-ammonia mixture, urea and ammonium sulfate, which were added in doses: N30; N45 one time; and N30 + N15 under pre-sowing cultivation and in the "fir tree" phase against the background of P30K60. The total number of variants was 16. The object of research was a variety of flax oilseed crops of breeding of the Institute of Oilseeds of NAAS. The seed sowing rate is 6 mln similar seed per hectare. According to the results of three-year studies, the effect of intensification of mineral nitrogen feed and various forms of nitrogen fertilizers on the indices of the elements of productivity and yield of flaxseed oil has been established. In particular, it was found that their use had little effect on the density change of plant stem growth. The use of nitrogen fertilizers in the dose N45 on the background of P30K60 improved plant survival (killed during the vegetation of 0.33-0.42 million pp./ha, which is 5.2-6.3 % for control, where the death observed 0.58 million ppm/ha or 8.4 %)) compared to the N30 dose (0.39-0.49 million pcs/ha). In addition, the use of the dose N45 separately (N30 under cultivation + N15 in the phase of the "fir tree") also improved the survival rate of plants (5.2-5.8 % of dead plants) compared with the simultaneous application of N45 cultivation (5.6-7.1 %) The percentage of deaths grew in control (without fertilizers) - 8.4 % against the background of P30K60 - 7.0 %. The application of various forms and doses of nitrogen fertilizers led to an increase in the control of the elements of productivity. The introduction of N45 against the background of P30K60 contributed to an increase in the number of boxes on plants, according to the variants of fertilizers, this index varied from 14.6 to 18.3 pieces per plant (10.9 - on the control, 12.9 pcs/roll - on the РК background), increasing the amount of seeds per plant by 12.7 pc. per plant, a mass of 1000 seeds per 0.2-0.3 g compared with the control and 0.1-0.2 g compared with the LCD background, where this figure was 6.8 g. On average, over the years of research, the highest productivity of flax seed of oilseed Vodograi (2,27 and 2,48 t / ha) was obtained provided the mineral fertilizer N15P30K60 was applied for cultivation in combination with carbamide feed in the phase of "fir tree" at a dose of N15. When using the nitrogen component in the form of KAS, the gain to control was 1.45 t / ha, to the background - 1.12 t/ha. In control and against the background, this indicator was 1.04 and 1.36 t/ha respectively. When using other forms of nitrogen fertilizers on the background of P30K60, lower yields of flaxseed crops were obtained (1.37-1.38 t/ha). The introduction of the N45 separately (N30 under cultivation + N15 into the "fir tree" phase) generally led to higher performance than a single application for cultivation. Among the studied forms of fertilizers, urea and carbamide-ammonia also caused a slightly higher percentage of fiber content in flax stems, however, it was within the experimental error and was not significantly increased.


2017 ◽  
Vol 68 (11) ◽  
pp. 2687-2690 ◽  
Author(s):  
Bogdan Mihnea Ciuntu ◽  
Stefan Octavian Georgescu ◽  
Ciprian Cirdeiu ◽  
Daniel Timofte ◽  
Doina Azoicai ◽  
...  

The study aims to assess the significance of negative pressure therapy in the treatment of 1 January 2014 - 31 June 2017. The objectives intend to evaluate the healing time required after applying the method and the functional consequences for the patient. A prospective study was conducted on a sample of 31 patients with various tipe of wounds which were monitored their clinical course between September 2014 - February 2017, following negative pressure therapy. There were used vacuum assisted closure devices (VAC � -Hartman) in order to apply negative pressure to the wound, while complying with specified settings in accordance with patients� outcome. Healing was obtained in all cases, to an average hospital stay of 30 days and 12 days of therapy application.The negative result of microbial cultures was obtained after an average of 7.55 days by simultaneous application of negative pressure and antibiotic treatment according to the antibiogram. After basic treatment of the wound, auxiliary methods such as negative pressure contribute to the healing. Evolution was favorable with wound granulation in 95% cases, which allowed surgery under local anesthesia, and defect was covered with skin graft. VAC therapy falls into the last group of treatments by eliminating healing inhibitors. This regenerates the wound in a damp environment and essentially turns an open wound into a closed system.


2017 ◽  
Vol 68 (7) ◽  
pp. 1648-1651
Author(s):  
Bogdan Mihnea Ciuntu ◽  
Ciprian Vasiluta ◽  
Robert Negru ◽  
Roxana Hultoana ◽  
Roxana Ciuntu ◽  
...  

The study aims to assess the significance of negative pressure therapy in the treatment of diabetic foot.The objectives intend to evaluate the healing time required after applying the method and the functional consequences for the patient. A prospective study was conducted on a sample of 37 patients with diabetic foot were monitored their clinical course between September 2014 - April 2017, following negative pressure therapy. There were used vacuum assisted closure devices (VAC � -Hartman) in order to apply negative pressure to the wound, while complying with specified settings (negative pressure, time of use of a kit) in accordance with patients� outcome.There were monitored changes in wound size (planimetric and volumetric measurement), their bacterial load and duration of treatment. Healing was obtained in all cases, to an average hospital stay of 27.3 days and 8 days of therapy application.The negative result of microbial cultures was obtained after an average of 6.45 days by simultaneous application of negative pressure and antibiotic treatment according to the antibiogram. Skin grafts were necessary to close the defect in 4 cases. After basic treatment of the wound, auxiliary methods such as negative pressure contribute to the healing.In patients with diabetic foot who were required surgical intervention, the use of negative pressure therapy yielded a significant benefit in the preservation of the affected limb, after minimal excision.The results we obtained throughout our experience recommend use of NPTW technique as indication for abdominal wall surgery in closing abdominal wall defects, compartment syndrome and surgical site infection after prosthetic mesh.


2017 ◽  
Vol 63 (1) ◽  
pp. 146-152
Author(s):  
Mikhail Ter-ovanesov ◽  
Aleksandr Levitskiy ◽  
E. Lesnidze ◽  
Aram Gaboyan ◽  
Mariya Kukosh ◽  
...  

In the current oncological practice surgical treatment of gastroesophageal cancer with high involvement of the esophagus can extend to total esophago-gastrectomy with colonic interposition as the main method of radical treatment. However the technical complexity and high risk of the intervention are factors in determining the divergent views on the operation itself, testimony for the criteria of patient’s selection, choice of surgical access and the formation of a colonic graft in conjunction with method of esophageal reconstruction. The long-term results of operative intervention depend primarily on the extent of tumor process but obviously higher than after conservative treatment. This article presents a brief critical overview of the main aspects of the simultaneous application of esophago-gastrectomy in surgery of gastroesophageal cancer with high esophageal involvement and our clinical case of successful surgical treatment of a woman with pregnancy-associated gastroesophageal cancer.


2020 ◽  
Vol 17 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Ho Jun Yi ◽  
Jae Hoon Sung ◽  
Dong Hoon Lee

Objective: We investigated whether intravenous thrombolysis (IVT) affected the outcomes and complications of mechanical thrombectomy (MT), specifically focusing on thrombus fragmentation. Methods: The patients who underwent MT for large artery occlusion (LAO) were classified into two groups: MT with prior IVT (MT+IVT) group and MT without prior IVT (MT-IVT) group. The clinical outcome, successful recanalization with other radiological outcomes, and complications were compared, between two groups. Subgroup analysis was also performed for patients with simultaneous application of stent retriever and aspiration. Results: There were no significant differences in clinical outcome and successful recanalization rate, between both groups. However, the ratio of pre- to peri-procedural thrombus fragmentation was significantly higher in the MT+IVT group (14.6% and 16.2%, respectively; P=0.004) compared to the MT-IVT group (5.1% and 6.8%, respectively; P=0.008). The MT+IVT group required more second stent retriever (16.2%), more stent passages (median value = 2), and more occurrence of distal emboli (3.9%) than the MT-IVT group (7.9%, median value = 1, and 8.1%, respectively) (P=0.004, 0.008 and 0.018, respectively). In subgroup analysis, the results were similar to those of the entire patients. Conclusion: Thrombus fragmentation of IVT with t-PA before MT resulted in an increased need for additional rescue therapies, and it could induce more distal emboli. The use of IVT prior to MT does not affect the clinical outcome and successful recanalization, compared with MT without prior IVT. Therefore, we need to reconsider the need for IVT before MT.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1010
Author(s):  
Przemysław Snopiński ◽  
Tibor Donič ◽  
Tomasz Tański ◽  
Krzysztof Matus ◽  
Branislav Hadzima ◽  
...  

To date, numerous investigations have shown the beneficial effect of ultrasonic vibration-assisted forming technology due to its influence on the forming load, flow stress, friction condition reduction and the increase of the metal forming limit. Although the immediate occurring force and mean stress reduction are known phenomena, the underlying effects of ultrasonic-based material softening remain an object of current research. Therefore, in this article, we investigate the effect of upsetting with and without the ultrasonic vibrations (USV) on the evolution of the microstructure, stress relaxation and hardness of the AlMg3 aluminum alloy. To understand the process physics, after the UAC (ultrasonic assisted compression), the microstructures of the samples were analyzed by light and electron microscopy, including the orientation imaging via electron backscatter diffraction. According to the test result, it is found that ultrasonic vibration can reduce flow stress during the ultrasonic-assisted compression (UAC) process for the investigated aluminum–magnesium alloy due to the acoustic softening effect. By comparing the microstructures of samples compressed with and without simultaneous application of ultrasonic vibrations, the enhanced shear banding and grain rotation were found to be responsible for grain refinement enhancement. The coupled action of the ultrasonic vibrations and plastic deformation decreased the grains of AlMg3 alloy from ~270 μm to ~1.52 μm, which has resulted in a hardness enhancement of UAC processed sample to about 117 HV.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4492
Author(s):  
Komeil Kohansal ◽  
Kamaldeep Sharma ◽  
Saqib Sohail Toor ◽  
Eliana Lozano Sanchez ◽  
Joscha Zimmermann ◽  
...  

This study focuses on the valorization of the organic fraction of municipal solid waste (biopulp) by hydrothermal liquefaction. Thereby, homogeneous alkali catalysts (KOH, NaOH, K2CO3, and Na2CO3) and a residual aqueous phase recirculation methodology were mutually employed to enhance the bio-crude yield and energy efficiency of a sub-critical hydrothermal conversion (350 °C, 15–20 Mpa, 15 min). Interestingly, single recirculation of the concentrated aqueous phase positively increased the bio-crude yield in all cases, while the higher heating value (HHV) of the bio-crudes slightly dropped. Compared to the non-catalytic experiment, K2CO3 and Na2CO3 effectively increased the bio-crude yield by 14 and 7.3%, respectively. However, KOH and NaOH showed a negative variation in the bio-crude yield. The highest bio-crude yield (37.5 wt.%) and energy recovery (ER) (59.4%) were achieved when K2CO3 and concentrated aqueous phase recirculation were simultaneously applied to the process. The inorganics distribution results obtained by ICP reveal the tendency of the alkali elements to settle into the aqueous phase, which, if recovered, can potentially boost the circularity of the HTL process. Therefore, wise selection of the alkali catalyst along with aqueous phase recirculation assists hydrothermal liquefaction in green biofuel production and environmentally friendly valorization of biopulp.


2021 ◽  
Vol 3 (9) ◽  
pp. 4504-4511
Author(s):  
Chao Bai ◽  
Lei Yan ◽  
Huai-Ming Hu ◽  
Feng Zou ◽  
Tian-Hua Zhang ◽  
...  

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