bluuebunny/crossref_metadata_2025_split huggingface dataset:
CXCR7: A β-arrestin-biased receptor that potentiates cell migration and recruits β-arrestin2 exclusively through Gβγ subunits and GRK2
Authors: Nguyen Huong Thi , Alcaraz Arfaxad Reyes , Yong Hyo Jeong , Nguyen Lan Phuong , Park Hee kyung , Inoue Asuka , Lee Cheol Soon , Seong Jae Young , Hwang Jong-Ik 
Published: November 2020

Abstract
Background: Some chemokine receptors referred to as atypical chemokine receptors (ACKRs) are thought to non-signaling decoys because of their inability to activate typical G-protein signaling pathways. CXCR7, also known as ACKR3, binds to only two chemokines, SDF-1a and I-TAC, and recruits b-arrestins. SDF-1a also binds to its own conventional receptor, CXCR4, involving in homeostatic modulation such as development and immune surveillance as well as pathological condition such as inflammation, ischemia, and cancers. Recently, CXCR7 is suggested as a key therapeutic target together with CXCR4 in such conditions. However, the molecular mechanisms underlying cellular responses and functional relation with CXCR7 and CXCR4 have not been elucidated, despite massive studies. Therefore, we aimed to reveal the molecular networks of CXCR7 and CXCR4 and compare their effects on cell migration.Methods: Base on structural complementation assay using NanoBiT technology, we characterized the distinct mechanisms underlying β-arrestin2 recruitment by both CXCR4 and CXCR7. Crosslinking and immunoprecipitation were conducted to analyze complex formation of the receptors. Gene deletion using CRISPR and reconstitution of the receptors were applied to analysis of ligand dependent ERK phosphorylation and cell migration. All experiments were performed in triplicate and repeated more than three times. Unpaired Student’s t-tests or ANOVA using PRISM5 software were employed for statistical analyses.Results: Ligand binding to CXCR7 does not result in activation of typical signaling pathways via Gα subunits but activation of GRK2 via βγ subunits and receptor phosphorylation with subsequent β-arrestin2 recruitment. In contrast, CXCR4 induced Gai activation and recruited β-arrestin2 through C-terminal phosphorylation by both GRK2 and GRK5. SDF-1a-stimulated ERK phosphorylation was facilitated by CXCR4, but not CXCR7. Heterodimerization of CXCR4 and CXCR7 was not confirmed in this study, while homodimerization of them was verified by crosslinking experiment and NanoBiT assay. Regarding to chemotaxis, SDF-1a-stimulated cell migration was mediated by both CXCR4 and CXCR7.Conclusion: This study demonstrates that SDF-1a-stimulated CXCR7 mediates β-arrestin2 recruitment via different molecular networking from that of CXCR4. CXCR7 may be neither a simple scavenger nor auxiliary receptor but plays an essential role in cell migration through cooperation with CXCR4.
Relationship between Admission Criteria andAcademic Performance in Basic Science Courses in Health Science Colleges in KAU
Authors: Alamoudi Aliaa Amr , Falattah Hind Ibrahim , Eldakhakhny Basmah Medhat , kamel Fatemah Omar , AlSawwa Lana Adey , Elsamanoudy Ayman Zaky 
Published: November 2020

Abstract
Background: In King Abdulaziz University, medical and health science schools depend on admission exams (Aptitude and Achievement) and Preparatory year scores in their students’ selection. However, with the growing number of applicants and the drastic changes in teaching and assessment in these colleges continuous assessment and development of admission criteria are needed. In this study, we aimed to evaluate the correlation of admission exam scores, in addition to the Preparatory year GPA, with academic performance in the basic science subjects such as Clinical Biochemistry and Clinical Pharmacology in health science colleges.Methods: The study was conducted on four cohort studies, two faculty of nursing cohorts; Nursing students (2017-2018,n=146) Nursing students (2018-2019,n=81), and two faculty of applied medical sciences cohorts, Clinical Nutrition students (2017-2018,n=33), Clinical Nutrition students (2018-2019,n=28) .The students’ scores of General Aptitude Test (GAT), Scholastic Achievement Admission Test (SAAT ), and preparatory year GPA were all recorded at the beginning of each semester before the beginning of courses. Clinical Biochemistry and Clinical Pharmacology exam results were recorded at the end of the semester. Correlation was done for each cohort and all cohorts pooled. Results: Results showed only a weak correlation detected between SAAT and the overall achievement in Clinical Biochemistry ( r= 0.192*, P= 0.042) in Nursing students (2017-2018) but no correlation was seen with SAAT or preparatory year scores. There was also no significant correlation between admission exams scores and the students ‘academic achievement in Clinical Pharmacology, and with On the other hand Clinical Pharmacology exam results showed a significant positive correlation with Clinical Biochemistry results (r=0.688, P=0.000). Conclusion: Our results could indicate the need to revisit the admission criteria for these colleges. Furthermore, specific preparatory year tracks for health science colleges can ensure that students improve the specific skills and knowledge required for their future college years.
Unexpected increase of myocardial extracellular volume fraction in low cardiovascular risk HIV patients
Authors: BORRAZZO CRISTIAN , d'Ettorre Gabriella , Ceccarelli Giancarlo , Pacilio Massimiliano , Santinelli Letizia , Cavallari Eugenio Nelson , Spagnolello Ornella , Silvestri Valeria , Vassalini Paolo , Scagnolari Carolina , Francone Marco , Mastroianni Claudio Maria , Carbone Iacopo 
Published: November 2020

Abstract
Background: People living with HIV (PLWH) are prone to develop sub-clinical Cardiovascular (CV) disease, despite the effectiveness of combined Antiretroviral Therapy (cART). Algorithms developed to predict CV risk in the general population could be inaccurate when applied to PLWH. Myocardial Extra-Cellular Matrix (ECM) expansion, measured by computed tomography, has been associated with an increased CV vulnerability in HIV-negative population. Measurement of Myocardial Extra-Cellular Volume (ECV) by computed tomography or magnetic resonance, is considered a useful surrogate for clinical evaluation of ECM expansion. In the present study, we aimed to determine the extent of cardiovascular involvement in asymptomatic HIV-infected patients with the use of a comprehensive cardiac computed tomography (CCT) approach.Materials and methods: In the present study, ECV in low atherosclerotic CV risk PLWH was compared with ECV of age and gender matched HIV- individuals. 53 asymptomatic HIV+ individuals (45 males, age 48 (42.5-48) years) on effective cART (CD4+ cell count: 450 cells/μL (IQR: 328-750); plasma HIV RNA: <37 copies/ml in all subjects) and 18 age and gender matched controls (14 males, age 55 (44.5-56) years) were retrospectively enrolled. All participants underwent CCT protocol to obtain native and postcontrast Hounsfield unit values of blood and myocardium, ECM was calculated accordingly.Results: The ECV was significantly higher in HIV+ patients than in the control group (ECV: 31% (IQR: 28%-31%) vs 27.4% (IQR: 25%-28%), p<0.001). The duration of cART (standardized β=0.56 (0.33-0.95), p=0.014) and the years of exposure to HIV infection (standardized β=0.53 (0.4-0.92), p<0.001), were positively and strongly associated with ECV values. Differences in ECV (p<0.001) were also observed regarding the duration of cART exposure (<5 years, 5-10 years and >10 years). Moreover, ECV was independently associated with age of participants (standardized β = 0.42 (0.33-0.89), p=0.084).Conclusions: HIV infection and exposure to antiretrovirals play a detrimental role on ECV expansion. An increase in ECV indicates ECM expansion, which has been associated to a higher CV risk in the general population. The non-invasive evaluation of ECM trough ECV could represent an important tool to further understand the relationship between HIV infection, cardiac pathophysiology and the increased CV risk observed in PLWH.
Experiences of Frontline Pakistani Emigrant Physicians Combating COVID-19 in the United Kingdom: A Qualitative Phenomenological Analysis
Authors: Saleem Javeria , Ishaq Muhammad , Zakar Rubeena , Suddahazai Imran Hussain Khan , Fischer Florian 
Published: November 2020

Abstract
Background: This study aims to explore the experiences, beliefs, feelings and challenges faced by Pakistani migrant doctors working in the United Kingdom in times of the COVID-19 pandemic. This qualitative approach was chosen to document their lived experiences and to develop a post-COVID-19 response to help them recover from their shared and individual traumas.Methods: An empirical phenomenological approach was used to collate data on experiences made during the COVID-19 pandemic. Purposive and snowball sampling was used to target participants, which were doctors of Pakistani origin involved in the direct care and management of COVID-19 patients in different NHS hospitals of the United Kingdom. Semi-structured, in-depth telephonic interviews were conducted with study participants in May 2020. Data collection was done parallel with data analysis by using standard qualitative methods.Results: We recruited ten frontline physicians. Four theme categories emerged from the data analysis: 1) Working across borders and cultures, 2) Role of beliefs for coping stress and fear, 3) Passion and profession, and 4) Scaffolding the Pakistani health system. Overall, the results show that the participants received no professional support, in terms of counselling and psychological rehabilitation. Instead, they had to use self-management strategies to cope with the situation. Conclusion: The intensive work exhausted participants physically and emotionally. They were holding a lot of grief and hurt inside; but still healthcare professionals showed the spirit of professional dedication to overcome difficulties. Although currently coping with their emotional problems, comprehensive professional support should be made available to them in order to cater for the wellbeing of frontline physicians.
Overexpression of Medicago sativa cv. Pianguan miR397-5p gene enhances drought tolerance in K326 tobacco
Authors: Zhu Huisen , Jia Rong , Tao Jiali , Jiang Junbing , Dong Kuanhu 
Published: November 2020

Abstract
Background

Alfalfa (Medicago sativa cv. Pianguan) is one of the most widely cultivated perennial leguminous forage. Drought is one of the major abiotic factors that affect alfalfa productivity. MicroRNAs (miRNAs) have been proved playing important roles in plant growth, development and stress response.
Results

In this study, High-throughput sequencing (HTSeq) was used to identify the miRNAs and their target related to drought stress from polyethylene glycol treated and control alfalfa samples, differential expression analysis showed that a large number of miRNAs were down-regulated or up-regulated as a result of PEG-6000 stress. qRT-PCR and sequencing analysis results showed that the relative expression of 9 miRNAs and their target genes related to drought stress, 3 miRNAs were considered potential drought-responsive miRNAs, including miR159b, miR397-5p and unconservative_6_4438. The recombinant plasmid vector pBWA(V)KS-miR397 was constructed and introduced into tobacco successfully. 31 positive seedlings were obtained through the process of infection, co-culture, differentiation and rooting. The physiologieal variation of transgenic tobacco under drought stress was researched. Finally, a new tobacco variety with high drought resistance was obtained.
Conclusion

These finding although need further studies to confirm, these data provide a useful evidence for the possible involvement of miRNAs in the process of drought response in the alfalfa plant which could help explain the drought stress responses and to alleviate the adverse effects of drought stress on plant growth and development.
A Small-Scale Qualitative Study of Early Comprehensive Patient Engagement in Acute Clinical Settings: Is It Feasible?
Authors: Jensen Andrea Nedergaard , Andersen Ove , Gamst-Jensen Hejdi , Kristiansen Maria 
Published: November 2020

Abstract
Background: Patient-centered care (PCC) based on systematic and comprehensive patient engagement is important for patient satisfaction. However, ensuring PCC is difficult in emergency departments (ED) characterized by a high patient flow and a substantial proportion of older adults with multimorbidity and complex care needs. This small-scale qualitative study aimed to identify potentials and barriers for providing early PCC for older adults in Danish EDs using a novel user-engagement conversation tool.Methods: Participant observation, focus group interviews and individual semi-structured interviews with ED nurses and geriatric nurses were conducted between September and December 2019 in an ED at a hospital in the Capital Region of Denmark. Thematic network analysis with a focus on potentials and barriers for patient engagement was conducted.Results: Two key subthemes related to potentials emerged: 1) a positive attitude towards patient engagement in the context of PCC, and; 2) perceived benefits of PCC overall and the engagement tool in particular. Additionally, two key subthemes related to barriers emerged: 1) time constraints and; 2) concerns related to the importance of cross-sectoral care coordination.Conclusion: This study contributes to mounting evidence in support of policies and practices that encourage PCC as a driver of unpacking patients’ needs and values leading to targeted follow-up care. However, barriers such as time constraints, and lack of cross-sectoral care collaboration should be acknowledged if the potentials of PCC is to be fulfilled in ED settings.
Development and Validation for Prognostic Nomogram of Epithelial Ovarian Cancer Recurrence based on Circulating Tumor Cells and Epithelial–Mesenchymal Transition
Authors: Yang Jiani , Ma Jun , Jin Yue , Cheng Shanshan , Huang Shan , Zhang Nan , Wang Yu 
Published: November 2020

Abstract
We aimed to determine prognosis value of circulating tumor cells(CTCs) undergoing epithelial–mesenchymal transition(EMT) in epithelial ovarian cancer(EOC) recurrence. We used CanPatrol CTC-enrichment technique to detect CTCs from blood samples and classify subpopulations into epithelial, mesenchymal and hybrids. To construct nomogram, prognostic factors were selected by Cox regression analysis. Risk stratification was performed through Kaplan–Meier analysis among training group(n=114) and validation group(n=38). By regression screening, both CTC counts(HR 1.187; 95%CI 1.098-1.752; p=0.012) and M-CTC(HR 1.098; 95%CI 1.047-1.320; p=0.009) were demonstrated as independent factors for recurrence. Other variables including pathological grade, FIGO stage, lymph node metastasis, ascites and CA-125 were also collected(p < 0.005) to construct nomogram. The C-index of internal and external validation for nomogram was 0.913 and 0.874. We found significant predictive value for nomogram with/without CTCs (AUC 0.8705 and 0.8097). Taking CTC counts and M-CTC into separation, the values were 0.8075 and 0.8262. Finally, survival curves of risk stratification based on CTC counts(p=0.0241), M-CTC(p=0.0107) and the nomogram(p=0.0021) were drawn with significant difference. In conclusion, CTCs could serve as a novel factor for EOC prognosis. Nomogram model constructed by CTCs and other clinical parameters could predict EOC recurrence and perform risk stratification for clinical decision-making.Trial registration: Chinese Clinical Trial Registry, ChiCTR-DDD-16009601, October 25, 2016
On-chip sampling of optical fields with attosecond resolution
Authors: Bionta Mina , Ritzkowsky Felix , Turchetti Marco , Yang Yujia , Mor Dario Cattozzo , Putnam William , Kärtner Franz , Berggren Karl , Keathley Phillip 
Published: November 2020

Abstract
We demonstrate an on-chip, optoelectronic device capable of sampling arbitrary, low-energy, near-infrared waveforms under ambient conditions with sub-optical-cycle resolution. Our detector uses field-driven photoemission from resonant nanoantennas to create attosecond electron bursts that probe the electric field of weak optical waveforms. Using these devices, we sampled the electric fields of ~5 fJ (6.4 MV m-1), few-cycle, near-infrared waveforms using ~50 pJ (0.64 GV m-1) near-infrared driving pulses. Beyond sampling these weak optical waveforms, our measurements directly reveal the localized plasmonic dynamics of the emitting nanoantennas in situ. Applications include broadband time-domain spectroscopy of molecular fingerprints from the visible through the infrared, time-domain analysis of nonlinear phenomena, and detailed investigations of strong-field light-matter interactions.
Transparent-Conductive-Oxide-Free Front Contacts for High Efficiency Silicon Heterojunction Solar Cells
Authors: Li Shenghao , Pomaska Manuel , Lambertz Andreas , Duan Weiyuan , Bittkau Karsten , Qiu Depeng , Yao Zhirong , Luysberg Martina , Steuter Paul , Koehler Malte , Qiu Kaifu , Hong Ruijiang , Shen Hui , Finger Friedhelm , Kirchartz Thomas , Rau Uwe , Ding Kaining 
Published: November 2020

Abstract
In order to compensate the insufficient conductance of heterojunction thin films, transparent conductive oxides (TCO) have been used for decades in both-sides contacted crystalline silicon heterojunction (SHJ) solar cells to provide lateral conduction for efficient carrier collection. In this work, we substitute the TCO layers by utilizing the lateral conduction of c-Si absorber, thereby enabling a TCO-free design. A series resistance of 0.32 Ωcm2 and a fill factor of 80.7% were measured for a TCO-free back-junction SHJ solar cell with a conventional finger pitch of 1.8 mm, thereby proving that relying on lateral conduction in the c-Si bulk is compatible with low series resistances. Achieving high efficiencies in SHJ solar cells with TCO-free front contacts requires suppressing deterioration of the passivation quality induced by direct metal-a-Si:H contacts and in-diffusion of metal into the a-Si:H layer. We show that an ozone treatment at the a-Si:H/metal interface suppresses the metal diffusion and improves the passivation without increasing the contact resistivity. SHJ solar cells with TCO-free front contacts and ozone treatment achieve efficiencies of > 22%.
Laboratory Testing Implications of Risk-Stratification and Management of COVID-19 Patients
Authors: Liu Caidong , Wang Ziyu , Wu Wei , Xiang Changgang , Wu Lingxiang , Li Jie , Hou Weiye , Sun Huiling , Wang Youli , Nie Zhenling , Gao Yingdong , Zhang Ruisheng , Li Kening , Xia Xinyi , Wang Qianghu , Wang Shukui 
Published: November 2020

Abstract
The progression from mild to critical illness is the main reason leading to the death of COVID-19 patients. Rapid risk-stratification at admission is important for precise management of COVID-19. Here, we developed a practical admission stratification model to predict the severity during hospitalization of COVID-19 patients using laboratory data from 3563 patients, including 548 patients in the training dataset, and 3015 patients in the testing dataset. We first identified the significant laboratory indicators related to the severity of COVID-19 in the training dataset. Neutrophils percentage (NEUT%), lymphocytes percentage (LYMPH%), creatinine (CREA), and blood urea nitrogen (BUN) with AUC greater than 0.7 were included in the model. These indicators were further used to build a support vector machine model to classify patients into low-risk and high-risk at admission. Results showed that this model could stratify the patients in the testing dataset effectively (AUC=0.89). Moreover, laboratory indicators detected in the first week after admission were able to estimate the probability of death (AUC=0.95). Besides, we could diagnose COVID-19 and differentiated it from other kinds of viral pneumonia based on laboratory indicators (accuracy=0.97). Our risk-stratification model based on laboratory indicators could help to diagnose, monitor, and predict severity at an early stage of COVID-19.
Teori Makna dalam Struktur Linguistik Arab Perspektif Mufasir Masa Klasik
Authors: Atabik Ahmad 
Published: November 2020

This article aims to examine the theory of meaning in the structure of Arabic linguistics that is studied by classical era commentators. In the classical era, the study that became a concentration of the study of al-Qur'an is the understanding of the meaning of the Qur'an with an Arabic linguistic approach. To get the ideal meaning from the verses of the Koran they pay attention to i’rab (Arabic grammar). They are concerned in the field of language criticism through grammatical, stylistic, and semantic approaches. Theories of meaning in classical times are supported by various works of classical Arabic linguists entitled Ma‘ānī al-Qur’ān, al-Farrā ’, al-Kisā’ī, al-Zajjāj, and al-Naḥḥās. These works are very significant in the development of the theorization of meaning from the point of view of the structure of the building (grammatical language). The theory of meaning is also supported by the study of stylistics (language style /uslūb). The study of the stylistic al-Qur'an in the theory of meaning is strengthened by al-Jā hiz and al-Jurjānī in their respective works. The final meaning theory can be found in the Qur'anic semantic studies. This study is considered as an ideal method in exposing the meaning of the Qur'anic language. Semantic studies of al-Qur'an are supported by the theory of al-wujūh wa al-naẓāir and siyāq (the context of the meaning of language). The study of the Wujūh and Naẓāir is a method of understanding the message of meaning which is possessed by the verses of the Qur'an, once studied by Ibn al-Jauzī. While siyāq is an indicator used in determining the meaning desired by mutakallim, it has been studied by Ibn Daqīq al-‘Id.
Formula for determining the size of the air tank in the long-distance water supply system
Authors: Chen Xuyun , Zhang Jian , Li Nan , Yu Xiaodong , Chen Sheng , Shi Lin 
Published: November 2020

Abstract
In the long-distance water supply system, the air tank can effectively protect the water hammer when the pump stops, and the shape parameters of the air tank determine the protective effect. Based on the theory of rigid water body and harmonic vibration, this paper derived the calculation formulas for the surge and bottom pressure changing process of the air tank in the system with and without friction and impedance and put forward the theoretical method to estimate the air tank volume and established the relationship between the operating parameters and the volume. Combined with the actual water supply project, under different working conditions, the theoretical calculation results and numerical simulation results were compared and analyzed. The results showed that the theoretical calculation results of the system with friction and impedance had a better fitting performance than the numerical simulation results, and the operating parameters of the air tank derived after considering the influence of friction and impedance were accurate. This method can simplify the selection process of air tank body parameters. At the same time, the shape optimization of the air tank considering friction and impedance can be improved by 40–50% compared with the results of ignoring friction and impedance.