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2021 ◽  
Author(s):  
Syaiful Choiri ◽  
Rafifah Fitriastuti ◽  
Firdausi Z Faradiva ◽  
Windy V Rahayu

As of recent, the appearance rate of several degenerative diseases and cancer influenced by oxidative stress continues to increase dramatically. Many compounds with high potential antioxidant activity have been explored and used extensively, i.e., as preventive or curative treatments. Stilbene and its derivates have high potential antioxidant activity contained in several botanical sources. To date, source exploration and antioxidant activity study of stilbene derivate has been reported. However, the nano-delivery of stilbene derivate meant to increase the antioxidant activity and stability is still a limited process. This review is devoted to brief and recent outlooks regarding the antioxidant activity and delivery system of the most frequently applied stilbene and its derivates, namely resveratrol and pterostilbene.


2021 ◽  
Author(s):  
Kequan Zhang ◽  
Qian Fang ◽  
Yihan Xie ◽  
Yujia Chen ◽  
Tong Wei ◽  
...  

Abstract Polyhydroxyalkanoate (PHA) is a new type of bio-polyester which is expected to replace traditional petroleum-based plastics. It is also a critical transformation hub of carbon source in nitrogen and phosphorus removal in sewage. Based on the anaerobic-oxygen limited process, the experiment took organic solid waste fermentation liquid as carbon source control hub and realized PHA synthesis and recovery in denitrification and phosphorus removal from low carbon sewage the SBR reactor by regulating pH value and nitrogen and phosphorus restriction. The experimental results showed that when the ratio of C/N and C/P was 150, the content of PHA accounted for 50.39% and 36.07 of the dry cell weight, respectively. Besides, it was found that increasing the C/N ratio was beneficial to increasing the proportion of PHV in PHA. This study proved the feasibility of using an anaerobic-oxygen limited process to recover PHA in nitrogen and phosphorus removal from low-carbon sewage, which saves gas and reduces energy consumption. At the same time, it also provides some help for the follow-up study of low-carbon urban sewage nitrogen and phosphorus removal coupled with resource recovery of PHA to guide the water industry economy to develop in a circular and sustainable direction


Author(s):  
Max Hossfeld

AbstractThis paper reports on the possibility of performing Friction Stir Welding (FSW) without the usual immanent shoulder to enable FS processing to deep welding of narrow and labile structures and applications where backing is not possible. Requirements and prerequisites, advantages and limitations for Shoulderless Friction Stir Welding (SLFSW) are discussed and an industrial application of the joining technology is presented. For leaving the shoulder out, its central functions in FSW have to be transferred to the pin. The resulting tool design of SLFSW is comparably small and slim and so reduces contact area and effective lever and in turn forces and heat input during processing. SLFSW allows welding paths almost at the edge of components and enables a complete and gap-free joining while a deformation of overhanging structures can be avoided. Compared to standard FSW processes, force reductions of about 80–85 % and power reductions of about 75–80 % were found in this study for a 6.5 mm deep weld opening up additional potential for integration with other spindle processes like milling. The locally very limited process impact of SLFSW resulted in comparably low distortion with a part precision reached of +/− 0.05 mm.


Gels ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 11
Author(s):  
Akitsugu Kawabata ◽  
Takao Yamamoto ◽  
Hiroki Shinoda ◽  
Kazuto Yoshiba ◽  
Yoshiharu Toyama ◽  
...  

Plasma is regarded as a solution of precursor polymers specifically transformed to gel-forming polymers by a reaction with initiators. We developed a theory for the gel growth dynamics of plasma induced by contact with a source of gelators that are yielded by the initiation. In developing the theory, we combined the Ginzburg–Landau type dynamics with the gelator diffusion dynamics expressed by the moving boundary picture. The theory predicts the crossover of the rate-limiting process in the time course of the thickness of the gel layer X from the energy-limited process expressed by X∼t to the diffusion-limited process expressed by X∼t, where t is the time elapsed from when the plasma comes into contact with the source of gelators. A demonstration experiment was performed by placing a tissue factor coating plate as the initiator in plasma. Log–log plot of X vs. t showed a crossover as predicted by the theory, and the parameters characterizing plasma were determined.


Cancers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2785
Author(s):  
Fabian Bernhard Pallasch ◽  
Udo Schumacher

Angiotensin inhibitors are standard drugs in cardiovascular and renal diseases that have antihypertensive and antifibrotic properties. These drugs also exert their antifibrotic effects in cancer by reducing collagen and hyaluronan deposition in the tumor stroma, thus enhancing drug delivery. Angiotensin II signaling interferes with the secretion of the cytokine TGF-β—a known driver of malignancy. TGF-β stimulates matrix production in cancer-associated fibroblasts, and thus drives desmoplasia. The effect of TGF-β on cancer cells itself is stage-dependent and changes during malignant progression from inhibitory to stimulatory. The intracellular signaling for the TGF-β family can be divided into an SMAD-dependent canonical pathway and an SMAD-independent noncanonical pathway. These capabilities have made TGF-β an interesting target for numerous drug developments. TGF-β is also an inducer of epithelial–mesenchymal transition (EMT). EMT is a highly complex spatiotemporal-limited process controlled by a plethora of factors. EMT is a hallmark of metastatic cancer, and with its reversal, an important step in the metastatic cascade is characterized by a loss of epithelial characteristics and/or the gain of mesenchymal traits.


2020 ◽  
Vol 13 (8) ◽  
pp. e234302
Author(s):  
Laura Cannon ◽  
Endi Wang ◽  
Mara Becker

Kikuchi-Fujimoto disease (KFD) is a rare lymphohistiocytic disorder which can cause prolonged fever and other systemic B symptoms including diffuse lymphadenopathy. Given its clinical presentation, there is often initial concern for lymphoma and diagnosis requires lymph node biopsy. It most frequently affects young women of Asian descent; it is less commonly encountered in paediatric patients. KFD is typically a benign, self-limited process, however, there is an association with development of systemic lupus erythematosus. Given its rarity, it remains unclear if KFD is associated with other chronic conditions. Here we present the third case of KFD occurring in a paediatric patient with sickle cell disease.


Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1518
Author(s):  
Anh T. Hoang ◽  
Yuriy V. Serdyuk ◽  
Stanislaw M. Gubanski

Charging and discharge currents measured in low-density polyethylene (LDPE) and LDPE/Al2O3 nanocomposite are analyzed. The experiments were conducted at temperatures of 40–80 °C utilizing a consecutive charging–discharging procedure, with the charging step at electric fields varying between 20 and 60 kV/mm. A quasi-steady state of the charging currents was earlier observed for the nanofilled specimens and it was attributed to the enhanced trapping process at polymer–nanofiller interfaces. An anomalous behavior of the discharge currents was found at elevated temperatures for both the studied materials and its occurrence at lower temperatures in the nanofilled LDPE was due to the presence of deeply trapped charges at polymer–nanofiller interfaces. The field dependence of the quasi-steady charging currents is examined by testing for different conduction mechanisms. It is shown that the space-charge-limited process is dominant and the average trap site separation is estimated at less than 2 nm for the pristine LDPE and it is at about 5–7 nm for the LDPE/Al2O3 nanocomposite. Also, location of the trapping sites in the band gap structure of the nanofilled material is altered, which substantially weakens electrical transport as compared to the unfilled counterpart.


Crystals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 166
Author(s):  
Dan Wang ◽  
Yu-xuan Feng ◽  
Ming Li ◽  
Shengdi Guo ◽  
Yuan Jiang

As many biominerals are formed in gel-like media, hydrogel-mediated mineralization is deemed as paradigms of biomineralization and ideal approaches to synthetic minerals with hierarchical architectures and related functions. Nevertheless, the long diffusion distance in hydrogels makes mineralization a diffusion-limited process, leading to isolated crystals instead of uniform hierarchical architectures. In the current study, seeded mineralization in silk fibroin hydrogel matrices is successful in delivering continuous rhombohedral CaCO3 films. Though the coverage of hydrogel matrices makes mineralization a diffusion-limited process, the presence of seed layers promotes the growth of uniform overlayers in proper conditions. The regulation of the solid content of hydrogels provides a rational route to rhombohedral architectures with tunable morphologies and thickness. In the course of mineralization, the hydrogel matrices are partially occluded in rhombohedral films as inter- and intra-crystalline constituents, as confirmed by scanning and transmission electron microscopy. Our study confirms the availability of synthesizing continuous mineralized films with hierarchical architectures and the structural gradient in hydrogel matrices via self-organized mineralization. These films with the occlusion of hydrogel constituents may exhibit significant strength and resilience, and their formation can deepen our mechanistic understanding of biomineralization proceeding in gel-like media.


Author(s):  
Martín Rodríguez-Álvaro ◽  

Grief is a natural and self-limited process of adaptation to a new reality that arises after a significant loss, real or perceived, with a wide range of manifestations that produce an impact on the health of the mourner. Objective: To know and identify, broken down by diagnostic gradient, the prevalence of mourning in the Canary Islands, as well as the needs of care before the diagnosis of mourning of the mourners. Results: Significantly, more women than men are identified in the three diagnostic labels under study. Patients with bereavement complications previously presented depression, anxiety, and risk of loneliness. The result of the pattern assessment is paradoxical. Conclusion: Grief is a multidimensional phenomenon that can hardly be assessed from a reductionist tool such as functional patterns. The high prevalence of complications in women’s grief should be studied in-depth, associating it with their previous burdens of care and vulnerability. The association between loneliness and complicated grief is evident, and the role of community nurses in these patients may be essential. Further research is needed on the care needs of bereaved persons, both complicated and uncomplicated, as well as on their predictive and protective factors.


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