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Metals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 155
Author(s):  
Feng Su ◽  
Guangtao Xu ◽  
Zhenhua Yao ◽  
Huachen Liu ◽  
Yikun Chen

High density of thermally stable Y-Si-O nanoparticles dispersed in the Fe matrix play a primary role in oxide dispersion strengthened (ODS) steel. In this study, the binding energies of solutes Y, O and Si with vacancies have been calculated in the framework of first-principles density functional theory. According to the calculations, any two solutes of Y, O and Si bound with each other strongly in the second nearest neighboring (NN) sites while not in 1NN. A vacancy (v) bounds strongly with Y and O in 1NN site. The binding sequence of solutes with v followed O-v → Y-v → Si-v, and the affinity of Y, Si and v with O followed O-Y → O-v → O-Si. The nucleation mechanism of Y-O-Si nanoclusters was determined, which gave the feasibility of adding Si to ODS steels. The core (consisting of Si and O)-shell (enriched Fe and Cr) structure of the microparticles was found in ODS steels containing Si, fabricated by mechanical alloying (MA) and vacuum sintering. Moreover the nanoparticles of monoclinic cubic Y2O3, Y2SiO5 and Y2Si2O7 with sizes of 5 ~ 12 nm were observed in ODS steel. Si reduced the sintering temperature by maximizing densities and mechanical properties at a lower sintering temperature. The steel with 3 wt% Si was sintered at 1280 °C, exhibiting the best comprehensive mechanical properties. The tensile strength, hardness and relative density were 1025 MPa, 442.44 HV and 95.3%, respectively.


Cells ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 232
Author(s):  
Ji Hye Jun ◽  
Sohae Park ◽  
Jae Yeon Kim ◽  
Ja-Yun Lim ◽  
Gyu Tae Park ◽  
...  

Changes in the structure and function of blood vessels are important factors that play a primary role in regeneration of injured organs. WKYMVm has been reported as a therapeutic factor that promotes the migration and proliferation of angiogenic cells. Additionally, we previously demonstrated that placenta-derived mesenchymal stem cells (PD-MSCs) induce hepatic regeneration in hepatic failure via antifibrotic effects. Therefore, our objectives were to analyze the combination effect of PD-MSCs and WKYMVm in a rat model with bile duct ligation (BDL) and evaluate their therapeutic mechanism. To analyze the anti-fibrotic and angiogenic effects on liver regeneration, it was analyzed using ELISA, qRT-PCR, Western blot, immunofluorescence, and immunohistochemistry. Collagen accumulation was significantly decreased in PD-MSCs with the WKYMVm combination (Tx+WK) group compared with the nontransplantation (NTx) and PD-MSC-transplanted (Tx) group (p < 0.05). Furthermore, the combination of PD-MSCs with WKYMVm significantly promoted hepatic function by increasing hepatocyte proliferation and albumin as well as angiogenesis by activated FPR2 signaling (p < 0.05). The combination therapy of PD-MSCs with WKYMVm could be an efficient treatment in hepatic diseases via vascular remodeling. Therefore, the combination therapy of PD-MSCs with WKYMVm could be a new therapeutic strategy in degenerative medicine.


Forests ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 102
Author(s):  
Fabrizio Michelangeli ◽  
Federico Di Di Rita ◽  
Alessandra Celant ◽  
Nadine Tisnérat-Laborde ◽  
Fabrizio Lirer ◽  
...  

This study presents the first Late Holocene marine pollen record (core ND2) from SE Sicily. It encompasses the last 3000 years and is one of the most detailed records of the south-central Mediterranean region in terms of time resolution. The combined approach of marine palynology and historical ecology, supported by independent palaeoclimate proxies, provides an integrated regional reconstruction of past vegetational dynamics in relation to rapid climatic fluctuations, historical socio-economic processes, and past land-use practices, offering new insights into the vegetation history of SE Sicily. Short-term variations of sparse tree cover in persistently open landscapes reflect rapid hydroclimatic changes and historical land-use practices. Four main phases of forest reduction are found in relation to the 2.8 ka BP event, including the Late Antique Little Ice Age, the Medieval Climate Anomaly, and the Little Ice Age, respectively. Forest recovery is recorded during the Hellenistic and Roman Republican Periods, the Early Middle Ages, and the last century. Agricultural and silvicultural practices, as well as stock-breeding activities, had a primary role in shaping the current vegetational landscape of SE Sicily.


2022 ◽  
Vol 221 (3) ◽  
Author(s):  
Sophia M. Hirsch ◽  
Frances Edwards ◽  
Mimi Shirasu-Hiza ◽  
Julien Dumont ◽  
Julie C. Canman

Contractile ring constriction during cytokinesis is thought to compact central spindle microtubules to form the midbody, an antiparallel microtubule bundle at the intercellular bridge. In Caenorhabditis elegans, central spindle microtubule assembly requires targeting of the CLASP family protein CLS-2 to the kinetochores in metaphase and spindle midzone in anaphase. CLS-2 targeting is mediated by the CENP-F–like HCP-1/2, but their roles in cytokinesis and midbody assembly are not known. We found that although HCP-1 and HCP-2 mostly function cooperatively, HCP-1 plays a more primary role in promoting CLS-2–dependent central spindle microtubule assembly. HCP-1/2 codisrupted embryos did not form central spindles but completed cytokinesis and formed functional midbodies capable of supporting abscission. These central spindle–independent midbodies appeared to form via contractile ring constriction–driven bundling of astral microtubules at the furrow tip. This work suggests that, in the absence of a central spindle, astral microtubules can support midbody assembly and that midbody assembly is more predictive of successful cytokinesis than central spindle assembly.


2022 ◽  
pp. e002010
Author(s):  
Conor Reid ◽  
C Hillman

Children are disproportionately affected by disasters. They have greater physiological, psychological and sociological vulnerabilities, often exacerbated by the fact that their unique needs can be overlooked during relief efforts. This article provides an overview of disasters, including how they are categorised, and the factors that need to be considered by military and civilian healthcare teams that respond to them. Information is drawn from a variety of previous disasters, with the effects considered across a range of different populations and communities. The lessons learnt from previous disasters need to inform the ongoing discussions around how to best train and supply both individual healthcare workers and the wider teams that will be expected to respond to future disasters. The importance of role-specific training incorporating caring for children, consideration of paediatric casualties during planning exercises and teaching scenarios, and the requirement for paediatric equipment and medications cannot be overemphasised. While provision of paediatric care may not be the primary role of an individual healthcare worker or their broader team, it still remains their ethical and often legal duty to plan for and deliver care for children when responding to a disaster. This is a paper commissioned as part of the Humanitarian and Disaster Relief Operations special issue of BMJ Military Health.


Author(s):  
Po-Yu Huang ◽  
Jen-Pi Tsai ◽  
Yen-Cheng Chen ◽  
Ming-Che Lee ◽  
Bang-Gee Hsu

The primary role of myostatin is to negatively regulate skeletal muscle growth. The gait speed is a noninvasive, reliable parameter that predicts cardiovascular risk and mortality. This study evaluated the relationship between serum myostatin concentrations and gait speeds in patients who had undergone kidney transplantation (KT). A total of 84 KT recipients were evaluated. A speed of less than 1.0 m/s was categorized into the low gait speed group. We measured serum myostatin concentrations with a commercial enzyme-linked immunosorbent assay. KT recipients in the low gait speed group had significantly older age, as well as higher body weight, body mass index (BMI), skeletal muscle index, serum triglyceride levels, glucose levels, and blood urea nitrogen levels, lower estimated glomerular filtration rates and serum myostatin levels, a higher percentage of steroid use, and a lower proportion of mycophenolate mofetil use. Multivariable logistic regression analysis revealed that lower myostatin levels and lower frequency of mycophenolate mofetil use were independently associated with low gait speed. In multivariable stepwise linear regression analysis, myostatin levels were positively correlated with gait speeds, and age and BMI were negatively correlated with gait speeds. In the study, serum myostatin levels were significantly lower in the low gait speed group. Subjects in the low gait speed group also had greater BMI and older age.


Author(s):  
Christopher L. Pankey ◽  
Kyle Flack ◽  
Kelsey Ufholz ◽  
LuAnn Johnson ◽  
James N. Roemmich

Abstract Purpose Models of appetite control have been largely based on negative feedback from gut and adipose signaling to central appetite centers. However, contemporary models posit that fat-free mass (FFM) or the energy demand of FFM [i.e., resting metabolic rate (RMR)] may play a primary role in the motivational drive for food intake (i.e., food reinforcement). The relative reinforcing value of food (RRVfood) is associated with energy intake (EI) and increases with an acute energy deficit. Chronic exercise-induced energy deficits lead to alterations in fat mass (FM), FFM, and RMR and provide an opportunity to test whether change in (∆) FM, ∆FFM, ∆usual EI, or ∆RMR are associated with ∆RRVfood. Methods Participants (n = 29, BMI = 25–35 kg/m2) engaged in aerobic exercise expending 300 or 600 kcal, 5 days/weeks for 12 weeks. The reinforcing value of food (PMaxfood) was measured via a computer-based operant responding task and RRVfood was calculated as the reinforcing value of food relative to non-eating sedentary behaviors. RMR was determined by indirect calorimetry and body composition by DXA. Results Post-training FFM correlated with usual post-training EI (rs = 0.41, p < 0.05), PMaxfood (rs=0.52, p < 0.01), and RMR (rs = 0.85, p < 0.0001). ∆RMR negatively correlated with ∆PMaxfood (rs = − 0.38, p < 0.05) and with ∆RRVfood (rs = − 0.37, p < 0.05). ∆PMaxfood and ∆RRVfood were not associated with ∆FFM (p = 0.71, p = 0.57, respectively). Conclusions Reductions in RMR with weight loss may increase food reinforcement as means of restoring FFM and RMR to pre-weight loss amounts. Limiting reductions in RMR during weight loss may benefit weight maintenance by restricting increases in food reinforcement after weight loss.


2022 ◽  
pp. 96-117
Author(s):  
Fidelis Ifeanyi Emoh ◽  
Don Macdonald ◽  
Charles Oham ◽  
Gladius Kulothungan

Provision of housing is vital to all the members of any country, and even a fundamental right of every person in a society to be housed properly. While the state has a primary role to play in reallocation of resources to meet the needs of the majority and ensure ‘public good', the economic status of developing nations has made this a complex issue. The developing world has increasingly come to rely on voluntary action, especially the social enterprise movements. There are marked differences in the approaches to tackling the social housing issue in the developed and developing world, from the point of view of the role played by social enterprises in this area. This chapter takes a comparative look at the role played by social entrepreneurs and social enterprises in the area of social housing in the developing and developed world by looking at some specific examples and case studies and concludes that in the developing world the social enterprise movement has a stronger role to play.


2021 ◽  
Vol 5 (3) ◽  
pp. 77-85
Author(s):  
Edlira PALLOSHI DISHA ◽  
Demush BAJRAMI ◽  
Agron RUSTEMI

In the conditions of a technological transformation of the media, professional credibility and reliability in information are fading due to the manipulative role that the media have taken. This paper, among other things, highlights exactly the editorial lines of the media, which do not build them on principles based on professional cause, but rather on the causes of political-media oligarchies. The fake news industry in the world is currently the most profitable product, and this is the most serious threat to democracies, which cannot be properly consolidated without a regulation in the dense "traffic" of online communication. In this industry Russia leads with its Sputnik, which has created a widespread establishment in the media space of Central and Eastern Europe. Preventing of this media "pandemic" is extremely complicated and costly, because this type of information is camouflaged in various forms and the public needs a proper media education to identify and differentiate fake news from true ones. Therefore, it is very necessary to create a national strategy of each state, to prevent the spread of this media "pandemic", while the most effective "virus" is the professionalization of the media and its detachment from the influence of political oligarchies. False news is creating its bedrock of influence and this is especially evident in the division of society as a result of political tensions and inter-ethnic discontent. Moreover, this paper shows that in such a divided society, the disinformation that circulates incessantly in the public space, sows fear. If a disinformation protection strategy were to be developed, then public confidence would not be in crisis, as it is currently in the Western Balkans, and the media would return to its primary role: independent and objective information.


2021 ◽  
Vol 10 (1) ◽  
pp. 83
Author(s):  
Roberto F. Coloma-Rivero ◽  
Manuel Flores-Concha ◽  
Raúl E. Molina ◽  
Rodrigo Soto-Shara ◽  
Ángelo Cartes ◽  
...  

Brucella, a Gram-negative bacterium with a high infective capacity and a wide spectrum of hosts in the animal world, is found in terrestrial and marine mammals, as well as amphibians. This broad spectrum of hosts is closely related to the non-classical virulence factors that allow this pathogen to establish its replicative niche, colonizing epithelial and immune system cells, evading the host’s defenses and defensive response. While motility is the primary role of the flagellum in most bacteria, in Brucella, the flagellum is involved in virulence, infectivity, cell growth, and biofilm formation, all of which are very important facts in a bacterium that to date has been described as a non-motile organism. Evidence of the expression of these flagellar proteins that are present in Brucella makes it possible to hypothesize certain evolutionary aspects as to where a free-living bacterium eventually acquired genetic material from environmental microorganisms, including flagellar genes, conferring on it the ability to reach other hosts (mammals), and, under selective pressure from the environment, can express these genes, helping it to evade the immune response. This review summarizes relevant aspects of the presence of flagellar proteins and puts into context their relevance in certain functions associated with the infective process. The study of these flagellar genes gives the genus Brucella a very high infectious versatility, placing it among the main organisms in urgent need of study, as it is linked to human health by direct contact with farm animals and by eventual transmission to the general population, where flagellar genes and proteins are of great relevance.


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