bluuebunny/crossref_metadata_2025_split huggingface dataset:
RETRACTED ARTICLE: Roles of the PI3K/AKT/mTOR signalling pathways in neurodegenerative diseases and tumours
Authors: Xu Fei , Na Lixin , Li Yanfei , Chen Linjun 
Published: April 2020

AbstractThe PI3 K/AKT/mTOR signalling pathway plays an important role in the regulation of signal transduction and biological processes such as cell proliferation, apoptosis, metabolism and angiogenesis. Compared with those of other signalling pathways, the components of the PI3K/AKT/mTOR signalling pathway are complicated. The regulatory mechanisms and biological functions of the PI3K/AKT/mTOR signalling pathway are important in many human diseases, including ischaemic brain injury, neurodegenerative diseases, and tumours. PI3K/AKT/mTOR signalling pathway inhibitors include single-component and dual inhibitors. Numerous PI3K inhibitors have exhibited good results in preclinical studies, and some have been clinically tested in haematologic malignancies and solid tumours. In this review, we briefly summarize the results of research on the PI3K/AKT/mTOR pathway and discuss the structural composition, activation, communication processes, regulatory mechanisms and biological functions of the PI3K/AKT/mTOR signalling pathway in the pathogenesis of neurodegenerative diseases and tumours.
Approximate Benson efficient solutions for set-valued equilibrium problems
Authors: Hu Shasha , Xu Yihong , Niu Zhichao 
Published: April 2020

AbstractIn locally convex Hausdorff topological vector spaces, the approximate Benson efficient solution is proposed for set-valued equilibrium problems and its relationship to the Benson efficient solution is discussed. Under the assumption of generalized convexity, by using a separation theorem for convex sets, Kuhn–Tucker-type and Lagrange-type optimality conditions for set-valued equilibrium problems are established, respectively.
Response solution to complex Ginzburg–Landau equation with quasi-periodic forcing of Liouvillean frequency
Authors: Wang Shimin , Liu Jie 
Published: April 2020

AbstractIn this paper, the existence of a response solution with the Liouvillean frequency vector to the quasi-periodically forced complex Ginzburg–Landau equation, whose linearized system is elliptic–hyperbolic, is obtained. The proof is based on constructing a modified KAM theorem for an infinite-dimensional dissipative system with Liouvillean forcing frequency.
Influence of time delay on bifurcation of a synthetic drug transmission model with psychological addicts
Authors: Zhang Zizhen , Yang Fangfang , Xia Wanjun 
Published: April 2020

AbstractA synthetic drug transmission model with psychological addicts and time delay is proposed in this paper. By analyzing the corresponding characteristic equation and choosing the time delay as the bifurcation parameter, a set of sufficient criteria guaranteeing local stability of the synthetic drug addiction equilibrium and the appearance of a Hopf bifurcation of the model is established. Further, the direction and stability of the Hopf bifurcation are investigated with the aid of normal form theory and center manifold theory. Finally, numerical simulations are performed to support the analytical results.
Detrimental effects of excessive fatty acid secretion on female sperm storage in chickens
Authors: Wen Chaoliang , Mai Chunning , Wang Bin , Li Junying , Sun Congjiao , Yang Ning 
Published: April 2020

Abstract
Background
Female sperm storage (FSS), the maintenance of sperm inside the female reproductive tract for an extended period of time, is pervasive among organisms with internal fertilization. Because FSS enables asynchronous mating and fertilization, it could be extremely important to reproduction. However, the physiological mechanisms underlying prolonged preservation and maintenance are poorly understood. Here, we used chicken, a typical oviparous animal, to determine the mechanisms ensuring sperm functionality in sperm storage tubules (SSTs).

Results
We performed an insemination experiment on over two thousand hens at two periods, and found that the FSS capabilities varied widely among individuals. Except for the differences in the SST density between the two groups with distinct FSS abilities, we quantitatively profiled small-molecule metabolites derived from SST cells, and identified 28 metabolites with differential expression. In particular, high levels of lipids, fatty acids and lipid peroxidation product were observed in hens with low FSS capability. Pathway analysis showed that these differential metabolites were significantly enriched in the biosynthesis of unsaturated fatty acids. Moreover, we detected the total antioxidant capacity and lipid peroxidation level of SSTs, and found that chickens with a lower FSS ability had a significantly higher content of lipid peroxidation end-product, which was 2.4-fold greater than chickens with a higher FSS capability, and no significant difference was found in the total antioxidant capacity between these two groups.

Conclusions
Our findings reveal that the long-term storage of sperm and the maintenance of their function in the female reproductive tract require an adequate microenvironment. The superabundance of fatty acids secreted by SST cells had detrimental effects on sperm storage in the female reproductive tract. Lipid peroxidation produces toxic biological substances that may cause irreversible damage to resident spermatozoa, resulting in short-term sperm retention and decreased fertility. Our findings provide new avenues for studying sperm storage and sustaining fertility.
Lung function and microbiota diversity in cystic fibrosis
Authors: Cuthbertson Leah , Walker Alan W. , Oliver Anna E. , Rogers Geraint B. , Rivett Damian W. , Hampton Thomas H. , Ashare Alix , Elborn J. Stuart , De Soyza Anthony , Carroll Mary P. , Hoffman Lucas R. , Lanyon Clare , Moskowitz Samuel M. , O’Toole George A. , Parkhill Julian , Planet Paul J. , Teneback Charlotte C. , Tunney Michael M. , Zuckerman Jonathan B. , Bruce Kenneth D. , van der Gast Christopher J. 
Published: April 2020

AbstractBackgroundChronic infection and concomitant airway inflammation is the leading cause of morbidity and mortality for people living with cystic fibrosis (CF). Although chronic infection in CF is undeniably polymicrobial, involving a lung microbiota, infection surveillance and control approaches remain underpinned by classical aerobic culture-based microbiology. How to use microbiomics to direct clinical management of CF airway infections remains a crucial challenge. A pivotal step towards leveraging microbiome approaches in CF clinical care is to understand the ecology of the CF lung microbiome and identify ecological patterns of CF microbiota across a wide spectrum of lung disease. Assessing sputum samples from 299 patients attending 13 CF centres in Europe and the USA, we determined whether the emerging relationship of decreasing microbiota diversity with worsening lung function could be considered a generalised pattern of CF lung microbiota and explored its potential as an informative indicator of lung disease state in CF.ResultsWe tested and found decreasing microbiota diversity with a reduction in lung function to be a significant ecological pattern. Moreover, the loss of diversity was accompanied by an increase in microbiota dominance. Subsequently, we stratified patients into lung disease categories of increasing disease severity to further investigate relationships between microbiota characteristics and lung function, and the factors contributing to microbiota variance. Core taxa group composition became highly conserved within the severe disease category, while the rarer satellite taxa underpinned the high variability observed in the microbiota diversity. Further, the lung microbiota of individual patient were increasingly dominated by recognised CF pathogens as lung function decreased. Conversely, other bacteria, especially obligate anaerobes, increasingly dominated in those with better lung function. Ordination analyses revealed lung function and antibiotics to be main explanators of compositional variance in the microbiota and the core and satellite taxa. Biogeography was found to influence acquisition of the rarer satellite taxa.ConclusionsOur findings demonstrate that microbiota diversity and dominance, as well as the identity of the dominant bacterial species, in combination with measures of lung function, can be used as informative indicators of disease state in CF.
Metabolic regulation of calcium pumps in pancreatic cancer: role of phosphofructokinase-fructose-bisphosphatase-3 (PFKFB3)
Authors: Richardson D. A. , Sritangos P. , James A. D. , Sultan A. , Bruce J. I. E. 
Published: April 2020

AbstractBackgroundHigh glycolytic rate is a hallmark of cancer (Warburg effect). Glycolytic ATP is required for fuelling plasma membrane calcium ATPases (PMCAs), responsible for extrusion of cytosolic calcium, in pancreatic ductal adenocarcinoma (PDAC). Phosphofructokinase-fructose-bisphosphatase-3 (PFKFB3) is a glycolytic driver that activates key rate-limiting enzyme Phosphofructokinase-1; we investigated whether PFKFB3 is required for PMCA function in PDAC cells.MethodsPDAC cell-lines, MIA PaCa-2, BxPC-3, PANC1 and non-cancerous human pancreatic stellate cells (HPSCs) were used. Cell growth, death and metabolism were assessed using sulforhodamine-B/tetrazolium-based assays, poly-ADP-ribose-polymerase (PARP1) cleavage and seahorse XF analysis, respectively. ATP was measured using a luciferase-based assay, membrane proteins were isolated using a kit and intracellular calcium concentration and PMCA activity were measured using Fura-2 fluorescence imaging.ResultsPFKFB3 was highly expressed in PDAC cells but not HPSCs. In MIA PaCa-2, a pool of PFKFB3 was identified at the plasma membrane. PFKFB3 inhibitor, PFK15, caused reduced cell growth and PMCA activity, leading to calcium overload and apoptosis in PDAC cells. PFK15 reduced glycolysis but had no effect on steady-state ATP concentration in MIA PaCa-2.ConclusionsPFKFB3 is important for maintaining PMCA function in PDAC, independently of cytosolic ATP levels and may be involved in providing a localised ATP supply at the plasma membrane.
Progress of infrared guided-wave nanophotonic sensors and devices
Authors: Ma Yiming , Dong Bowei , Lee Chengkuo 
Published: April 2020

AbstractNanophotonics, manipulating light–matter interactions at the nanoscale, is an appealing technology for diversified biochemical and physical sensing applications. Guided-wave nanophotonics paves the way to miniaturize the sensors and realize on-chip integration of various photonic components, so as to realize chip-scale sensing systems for the future realization of the Internet of Things which requires the deployment of numerous sensor nodes. Starting from the popular CMOS-compatible silicon nanophotonics in the infrared, many infrared guided-wave nanophotonic sensors have been developed, showing the advantages of high sensitivity, low limit of detection, low crosstalk, strong detection multiplexing capability, immunity to electromagnetic interference, small footprint and low cost. In this review, we provide an overview of the recent progress of research on infrared guided-wave nanophotonic sensors. The sensor configurations, sensing mechanisms, sensing performances, performance improvement strategies, and system integrations are described. Future development directions are also proposed to overcome current technological obstacles toward industrialization.
PD-1 and PD-L1 Expression in Peripheral CD4/CD8+ T Cells Is Restored in the Partial Remission Phase in Type 1 Diabetes
Authors: Li Xia , Zhong Ting , Tang Rong , Wu Chao , Xie Yuting , Liu Fang , Zhou Zhiguang 
Published: April 2020

Abstract

Context
Partial remission (PR) in type 1 diabetes (T1D) is accompanied by downregulation of the immune response. Programmed cell death-1 (PD-1) and its ligand (PD-L1) are important immunosuppressive molecules, but their changes in the PR phase are unclear.

Objective
We investigated the dynamic changes of PD-1/PD-L1 expression on T cells around the PR phase in T1D.

Methods
Ninety-eight T1D patients were recruited cross-sectionally and grouped according to PR status into nonremitters (individuals who did not undergo PR during the disease course; n = 39), pre-PR (n = 15), mid-PR (n = 30), and post-PR (n = 14) subgroups. PR was defined according to C-peptide level ≥300 pmol/L or index of insulin-adjusted hemoglobin A1c ≤9 as recommended. Among all the 98 patients, 29 newly diagnosed individuals were prospectively followed up for 1 year. The dynamic changes of PD-1/PD-L1 expression, frequency of regulatory T cells (Tregs) and IL-35+ Tregs among peripheral CD4/CD8+ T cells were determined.

Results
PD-1/PD-L1 on CD4+/CD8+ T cells showed a dynamic change around the PR phase: lowest in pre-PR phase, restored in mid-PR phase, and declined again in post-PR phase. Conversely, this pattern did not occur for nonremitters. Notably, PD-1 expression on CD8+ T cells in mid-PR was positively correlated with the length of the PR phase. The percentages of circulating Tregs and IL-35+ Tregs showed no relation to PR.

Conclusions
The PR phase is associated with restoration of PD-1/PD-L1 on CD4+ and CD8+ T cells, suggesting that PD-1/PD-L1 may be a potential target for prolonging this phase in T1D.
Stress and associated risk factors among the elderly: a cross-sectional study from rural area of Thailand
Authors: Seangpraw Katekaew , Auttama Nisarat , Kumar Ramesh , Somrongthong Ratana , Tonchoy Prakasit , Panta Pitakpong 
Published: April 2020

Background. Stress is a common mental health problem of the elderly population that affects their quality of life. The objective of this study was to determine the level of stress and associated factors among the elderly living in rural areas of Thailand. Methods. This was a cross-sectional study conducted in two sub-districts of rural Thailand and interviewed 403 elderly persons. We used simple random sampling technique from a list of registered elderly individuals and conducted face-to-face interviews using a questionnaire. The questionnaire were piloted, validated and pretested beforehand. Multiple linear regression was applied for data analysis. This study was approved by the Ethical Review Committee of the University of Phayao, Thailand. Results. The mean age of the participants was 68 and two thirds (67%) were female. Less than 43% of the participants had moderate, and one third (34%) had high levels of stress. More than half of participants had low level stress management. Stress was significantly associated with alcohol and illness with a predictive power of 3.0% [(R = 0.173, R Square = 0.030) (p<0.05)]. Conclusion. We conclude that risk factors such as alcohol and illness affect elderly population living in rural areas of Thailand to a major extent in terms of stress.
Modeling and mitigation of fiber nonlinearity in wideband optical signal transmission [Invited]
Authors: Semrau Daniel , Sillekens Eric , Bayvel Polina , Killey Robert I. 
Published: April 2020

The adoption of open optical networks (OONs) requires the development of open and effective network planning tools, enabling the use of multi-vendor or white-box transport solutions. Such tools for studying and planning optical networks must be able to take into account the physical layer impairments, including fiber nonlinearity. The use of wideband wavelength division multiplexing in OONs, with channel frequencies extending across the short, conventional, and long bands and beyond, offers a pathway to increasing data rates through the installed fiber infrastructure. However, achievable information rates are limited by the resulting signal distortion due to fiber nonlinearity as signal bandwidths are increased, in particular, inter-channel stimulated Raman scattering (ISRS). In this paper, we describe the nonlinear effects observed in wideband transmission systems, and review recently developed analytical tools, based on the Gaussian noise (GN) model of nonlinear interference with the inclusion of ISRS. Using the ISRS GN model, we assess the impact of fiber nonlinearity on the achievable information rates in transmission systems with bandwidths of up to 12 THz. We demonstrate the use of the model in the optimization of launch power spectral profiles for a variety of dynamic gain equalizer arrangements in a 1000 km standard single-mode fiber link, using particle swarm optimization and the steepest descent algorithm. Such nonlinear models and optimization methods could be applied in OON planning tools, for example, in optical link emulators to estimate quality-of-transmission and data throughput, and in impairment-aware software-defined network control and management.
Suppression of reverberations at fiber tips for optical ultrasound sensing
Authors: Ma Xiangdong , Liu Bingxue , Cai Yiqi , Jia Donglin , Fu Bo , Xu Lijun , Ma Jianguo 
Published: April 2020

Fabry–Perot-based ultrasound sensors at fiber tips have performed high sensitivity and immunity of electromagnetic interference with a relatively compact size. Nevertheless, the reverberation at fiber tips causes a strong noise that degrades the sensing capability. Here we propose a fiber optical-based ultrasound sensor with three design approaches to reduce the reverberation, including designs with an eccentric core, absorptive shield, and arc edge. The effect was experimentally validated with a photoacoustic signal excitation. Compared with bare single-mode fibers in simulation, the low-reverberation design increased the signal-to-noise ratio by 32.1 dB with identical excitation. The experimental results demonstrated the “clean” response with almost invisible reverberations, which was validated by a commercial hydrophone. This research solved the reverberation problems and provided a low-noise design for fiber optic ultrasound sensing.
Graphene Q-switched Tb:LiYF4 green laser
Authors: Chen H. , Yao W. , Uehara H. , Yasuhara R. 
Published: April 2020

We report the

Q

-switched operation of a

T
b

3
+

-laser for the first time, to the best of our knowledge. The passive

Q

-switching was realized by a 15%

T
b

:

L
i
Y
F

4

gain medium and a single-layer graphene saturable absorber. An average output power of 744 mW at 544 nm was achieved with slope efficiency of 41%, pulse width of 2.9 µs, and repetition rate of 38.7 kHz. The corresponding pulse energy and peak power were calculated to be 19.2 µJ and 6.6 W, respectively.
Polityka młodzieżowa w województwie zachodniopomorskim – wymiar lokalny i regionalny
Authors: Szulc Marta 
Published: April 2020

W artykule podjęto tematykę polityki młodzieżowej w województwie zachodniopomorskim. Autorka w szczególności skupiła się na aspekcie lokalnym i regionalnym tejże polityki.
Jego celem jest diagnoza sytuacji polityki młodzieżowej w województwie zachodniopomorskim na poziomie regionalnym i lokalnym. Autorka postawiła następujące pytania badawcze: czy system funkcjonowania polityki młodzieżowej działa prawidłowo, jaki jest zakres tematyczny działalności rad młodzieży, czy młodzież angażująca się w politykę młodzieżową zna mechanizmy jej funkcjonowania w województwie zachodniopomorskim, czy Sekretariat ds. Młodzieży Województwa Zachodniopomorskiego oraz Rada Młodzieży Województwa Zachodniopomorskiego spełniają swoją funkcję dotyczącą prowadzenia polityki młodzieżowej w województwie zachodniopomorskim. Aby znaleźć odpowiedzi na powyższe pytania badawcze użyto: metody analizy danych zastanych, badania ankietowego oraz techniki wywiadów.
Przeprowadzone analizy wykazały rozpoznawalność i widoczność działań SdsM WZ i RMWZ w regionie. Pokazały, że RMWZ ma coraz wyraźniejszy wpływ na politykę młodzieżową oraz województwo zachodniopomorskie. Za pomocą analiz danych zaobserwowano prawidłową dynamikę powstawania rad młodzieży w województwie. Zdiagnozowano również pewne problemy polityki młodzieżowej tj. brak budżetu, brak współpracy z dorosłymi oraz niskie zaangażowanie młodzieży. Te elementy wymagają, w opinii autorki, dalszej pracy podmiotów zaangażowanych w politykę młodzieżową.
From Political Mobilization to Political Security. How Has the Approach to Security Changed Over Centuries and Why Has It Depended on Political Relations?
Authors: Skarzyński Ryszard , Kużelewska Elżbieta 
Published: April 2020

The paper discusses relations between political mobilization, security and political relations. Security is understood as a social phenomenon, clearly explained by Clausewitz in his book On War. According to Clausewitz, political relations are of key significance for understanding the phenomenon of security. This thesis is not challenged, however, it is necessary to explain why political relations are necessary.
The paper consists of four parties. The first part explores security and its evolution from a historical perspective. The second part analyses relations between a war and political mobilization. In our opinion, war is something more than simple continuation of politics by other means. Part three discusses the personal security, which was not a priority for the states. The problem of security appeared in its complex form only when people became ready to fight as a result of political mobilization, and with the creation of stable political organization. Section 4 describes political security and its consequences.
We conclude that the product of the global political mobilization is polyarchy which principally changes the problem of social and political security. Within the framework of regional polyarchy the system of security of states in the area occupied by it is possible. As a result of creating a global polyarchy the universal system of security has become real. The role of army has changed and to an ever decreasing extent fulfils the function of a traditional army. Mercenaries lost their importance (however, not completely) and later also the military troops acting on behalf of the state.
A descriptive study of brand equity of india's popular online shopping sites
Authors: Sandhe Ashutosh Anil 
Published: April 2020

The focus of this research was to measure consumer-based brand equity (CBBE) of India’s most popular online retailing websites Amazon and Flipkart. However, for the sake of confidentiality and copyright, their names were not revealed anywhere in the paper. This was done with the help of Aaker’s and Keller’s concept of brand equity. A sample of 1000 respondents from across the state of Gujarat, India was examined. CBBE was measured by calculating mean scores of overall brand equity and its factors like brand loyalty, perceived quality, brand awareness, brand association, attitude and purchasing intention. The correlation coefficient between factors and brand equity was considered as weight. The research revealed through the data which retail site had a higher brand equity. One interesting fact that was identified was how keenly both the brands are trying to woo their customers. The results showed very similar trends. A positive relation was found between brand equity and its factors. Based on this relationship the research concluded with a regression model where brand equity was the dependent variable and factors were independent variables. It was observed that the factor ‘brand loyalty’ had the lowest mean value suggesting that with competition and wider choice to consumer, brand loyalty tends to be lower. Favorable attitude was observed for both brands with highest mean values among all factors.