bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Dynamics Analysis on Hydrogenation Process of Asphaltene Aggregate for Medium and Low Temperature Coal Tar
Authors: Han Xiaokang , Yan Wenzhou , Liu Xu , Li Dong , Zhu Yonghong 
Published: March 2021

Abstract
In this paper, the average molecular structure models of middle-low temperature coal tar (MLCT) asphaltene before and after hydrogenation were obtained by 1H-NMR characterization. Then the aggregation structure models of MLCT asphaltenes before and after hydrogenation was constructed in Materials Studio 8.0 software. The comparative analysis of structural characteristics between original and hydrogenated asphaltenes were carried out. The final configuration, molecular rotation radius and interaction energy of asphaltene aggerates before and after hydrogenation were analyzed by molecular dynamic simulation in different solvents.The conclusions are as follows: (1) The MLCT asphaltenes exist in the form of asphaltene aggregates before and after hydrogenation. After structural optimization, the original asphaltene molecules become 2-3 asphaltene molecules with approximately parallel, orderly arrangement and polycyclic aromatic hydrocarbons (PAH) stacking aggregate structure. The molecular accumulation number of its aggregate is less than that of petroleum asphaltene, and more complex nano-aggregates are formed by self-assembly among multiple aggregates. The accumulation number of asphaltene molecules after MLCT hydrogenation are less than that of original asphaltene. (2) The total interaction between MLCT primary asphaltene and hydrogenated asphaltene mainly comes from the intermolecular Van der Waals force. Compared with original asphaltene, the van der Waals energy and electrostatic energy of hydrogenated asphaltene are smaller and more affected by temperature. This shows that the intermolecular interaction of hydrogenated asphaltene is weak and the structure of the aggregate is unstable. (3) Aromatic compounds, strong basic compounds and strong polar compounds have good dissociation effect on MLCT asphaltenes and can effectively inhibit the aggregation and asphaltenes.
Role of pH in The Stability of Cytosine-Cytosine Mismatch and Canonical AT &amp; GC Base Pairs Mediated With Silver Ion: A DFT Study
Authors: Bhai Surjit , Ganguly Bishwajit 
Published: March 2021

Abstract
Metallo-nucleic acids have been investigated for their applications in the field of nanodevices and genetic expansion. The cytosine-Ag+-cytosine mismatch base pair interactions and their stability in nucleic acids have attracted the attention of chemists. We report a systematic study of canonical, mismatch, Ag+ mediated system with CC, AT, and GC base pairs computationally. The stability of such mismatch base pairs is dependent on the pH range ~5 to 9 and the duplexes beyond this range are unstable. The DFT calculations performed with the model DNA duplexes comprising of such mismatch pairs reveal the stability trend while varying the pH conditions. The stability of canonical Watson-Crick ATGC base pairs was compared with the CCAT and CCGC mismatch base pairs and the calculated results at B3LYP-D3/6-31G* level of theory in the aqueous phase suggest that the base stacking and hydrogen bonding are well maintained in the former case, however, the larger perturbations in the geometry are observed with the mispair and relatively unstable. The calculated binding energy at B3LYP/6-31G* level of theory of ATGC is energetically more stable (~15 kcal/mol) than the mismatch base pairs. The Ag+ mediated mismatch base pairs i.e., C_CAT and C_CGC examined at the same level of theory suggest that the CC mismatch base pairs complexed with proper alignment to the Ag+ ion and the AT and GC bases maintained the hydrogen bonding interactions. The mismatched base pair duplex systems i.e., C_CAT and C_CGC are structurally similar to the canonical Watson-Crick base pairs and energetically stable by ~40 and ~50 kcal/mol compared to the canonical ATGC base pairs. The experimental report on the thermal transition profile in 5’-(A)10C(A)10-3’ and 5’ (T)10C(T)10-3’ duplexes showed remarkable stability and corroborate the calculated results.[1] The stability of Ag+ mediated mismatch bases at the higher pH 9 was also examined and the nucleobases such as guanine and thymine would be deprotonated under this condition. The calculated results suggest that the CCA_T and CCG_C duplexes are largely distorted with the complexation of Ag+ with the AT and GC base pairs and would in turn denature the duplex. The AIM analysis performed at B3LYP-D3/6-31G* level of theory for all the studied Ag+ mediated complexes reveals that the Ag+ interaction with the corresponding nucleobases was electrostatic in nature. The role of pH in governing the stability of C-Ag+-C complex formation in mismatch base nucleic acids is crucial for their application of genetic expansion and nucleic acid-based nanodevices.
Influence of Social Determinants of Health on Timeliness to Treatment for Metastatic HCC and the Impact of Affordable Care Act
Authors: Jayakrishnan Thejus , Bakalov Veli , Finley Gene , Monga Dulabh , Wegner Rodney E 
Published: March 2021

Abstract
BackgroundTo achieve progress in cancer treatment, socioeconomic disparities impacting the care need to be recognized and addressed. We hypothesized that social determinants of health may predict a delay in systemic therapy for metastatic hepatocellular carcinoma patients (HCC) and sought to examine the impact of the Affordable Care Act (ACA).MethodsNational Cancer Database (NCDB) was queried for patients with metastatic hepatocellular carcinoma diagnosed from 2004-2015 and considered for first line systemic therapy within 6 months (180 days) of diagnosis. Time to initiation (TTI) was defined as the time in days(d) from diagnosis of cancer to initiation of systemic therapy. Survival was measured in months(m) from the day of diagnosis. Multivariate analyses were performed using 2010 as a cut-off between pre-and post-ACA for analysis.Results630 patients meeting the eligibility criteria. Median TTI in the group was 57d. The only factor associated with delayed TTI (defined as the fourth quartile of TTI) in a multivariate logistic regression was non-Hispanic Black (NHB) race Odds Ratio OR 1.94(95%CI 1.0–3.3), p-value=0.052. The OR showed improvement with implementation of ACA – OR3.6(95%CI 1.4-9.4),p-value 0.008 during pre-ACA vs. 1.3(0.5-3.1),p-value=0.6 post-ACA. There was a non-significant trend towards higher mortality among NHB vs. NHW (HR 1.2, 95% CI 1.0-1.6) and lower mortality for those insured vs. uninsured (HR 0.8, 95% CI 0.5-1.1. ConclusionRace appears to impact timeliness to therapy in metastatic HCC patients and was positively impacted by ACA. Continued research to monitor disparities in care and identify underlying mechanisms to mitigate them are warranted.
Potential Use of Distinct Biomarkers (Trace Metals, Micronuclei and Nuclear Abnormalities) in a Heterogeneous Sample of Birds in Southern Brazil.
Authors: TOMAZELLI JOANA , Rodrigues Gabriela Zimmermann Prado , Franco Danielle , de Souza Mateus Santos , Burghausen Jorge Henrique , Panizzon Jenifer , Kayser Juliana Machado , Loiko Márcia Regina , Schneider Anelise , Linden Rafael , Gehlen Gunther 
Published: March 2021

Abstract
The analysis of metal concentrations in feathers and the micronuclei (MN) and other nuclear abnormalities (NA) test in birds are tools used for evaluating the impacts that anthropogenic actions have been causing to the environment and organisms. Here we used these biomarkers to investigate the response of birds to disturbances observed in three areas with different environmental characteristics (natural, agricultural and urban) in southern Brazil. We obtained a diverse sample (108 individuals from 25 species and 17 families) without significant differences in metal concentrations, frequency of MN and AN between sampling points. The concentrations of zinc (Zn) and copper (Cu) were significantly different between trophic guilds (Zn: p = 0.0006, Cu: p = 0.04) and age classes (Zn: p = 0.01, Cu: p = 0.03). Omnivore birds contributed to the increase in the number of MN (∆AICc: 0.00; w = 0.40) and NA, which was also influenced by age classes and body condition index (BCI) (∆AICc: 0.00; w = 0.34; ∆AICc: 0.89; w = 0.22; ∆AICc: 1.15; w = 0.19; ∆AICc: 1.33; w = 0.18). We showed that in a diverse sample of birds, the variables analyzed affected each biomarker in distinct ways.
Role of Ki-67, MRE11, and PD-L1 As Predictive Biomarkers for Recurrence Pattern in Muscle Invasive Bladder Cancer Following Radical Cystectomy
Authors: Fossum Croix C. , Xiong Yin , Magliocco Anthony , Daneshmand Siamak , Aron Manju , Mouw Kent W. , Manojlovic Zarko , McCarthy Susan , Phuong Christina , Dorff Tanya , Bhanvadia Sumeet K. , Ballas Leslie K. 
Published: March 2021

Abstract
Background

Muscle invasive bladder (MIBC) cancer is an aggressive disease with high rates of local recurrence following radical cystectomy (RC). Currently, there are no clinically validated biomarkers to predict local only recurrence (LOR) and guide adjuvant treatment decisions. This pilot study evaluated the role of Ki-67, MRE11 and PD-L1 as predictive biomarkers for recurrence patterns in patients undergoing RC for MIBC.
Methods:

Our institutional cystectomy database containing cases of urothelial MIBC from 1992–2014 was queried for patients with LOR and case-matched with patients who had distant recurrence (DR) and no recurrence (NR). Clinical and histopathological data were collected from selected patients and a tissue microarray was built and analyzed for presence of Ki-67, MRE11 and PD-L1 using immunofluorescence (IF) and immunohistochemistry (IHC). Univariate, multivariate, and principal component analyses (PCA) were performed to evaluate association of these biomarkers with recurrence pattern.
Results:

Pathologic specimens from 42 patients (18 NR, 16 LOR and 8 DR) were reviewed. Compared to adjacent normal bladder tissue, tumors had increased expression of PD-L1 on both IHC and IF (p < 0.05) and higher Ki-67 H-score on IHC (33 vs 0, p < 0.01). A high Ki-67 was associated with recurrence pattern (local vs distant) on univariate analysis (p < 0.05) and on multivariate regression, having positive surgical margins was associated with local recurrence (p = 0.04). Ki-67 cell density varied by recurrence type: LR (1354 cells/mm2), DR (557 cells/mm2) and NR (1111 cells/mm2) p = 0.034. Several PCAs were unable to identify a signature associated with recurrence pattern.
Conclusion:

The biomarkers used in this study were helpful in distinguishing tumor from normal tissue and high Ki-67 may be associated with LOR, however, a useful molecular signature for recurrence pattern could not be identified.
Harmonious Coexistence of Cultural Heritage Protection and Tourism: The Mount Lushan Comprehensive Tourism Platform
Authors: Zhenrao Cai , Chaoyang Fang , Qian Zhang , Fulong Chen 
Published: March 2021

Abstract
The coordinated development of heritage protection and tourism is the goal of both cultural heritage sites and sustainable heritage tourism. However, the development of sustainable heritage tourism can be restricted due to insufficient resources for heritage tourism marketing as well as insufficient cultural heritage protection measures. This study uses digital methods such as oblique photography, 3D laser scanning technology and panoramic technology to digitize the cultural landscape heritage site. Using these methods, we build a virtual tourism subsystem to improve tourists’ experience of cultural heritage tourism resources and enhance the attraction of cultural heritage tourism. In addition, we build a tourist flow and environmental monitoring and management subsystem based on the Internet of Things technology. This subsystem can help managers adjust and regulate tourist flow according to the tourism carrying capacity threshold. We also conduct an ecological environment health assessment and management simulation according to the “Pressure-Status- Response” model, in doing so, we aim to enhance the protection of cultural heritage sites. Finally, we develop a comprehensive platform to integrate tourism marketing and heritage protection management functions. The results of this study provide a new approach for the coordination of and symbiosis between the protection of cultural heritage and tourism activity.
Investigation of the Problem Behaviors Emerging in Children During the COVID-19 Pandemic
Authors: Sancili Semanur , Tugluk Mehmet Nur 
Published: March 2021

Abstract
Background: This study aimed to evaluate the effect of the COVID-19 pandemic on the problem behaviors of children within the framework of parental opinions. It furthermore examined how certain variables such as contact with an individual infected with COVID-19, positive COVID-19 test results in the family and/or close community, and death from COVID-19 in the family and/or close community affected the changes in children’s habits and problem behaviors. Methods: The study was conducted using a case study design in accordance with the qualitative research method. Within the scope of the study, 20 parents with children between 4 and 6 years of age were interviewed. Research data were collected with semi-structured interview forms and were analyzed using the content analysis method.Results: The analysis of parental opinions revealed that some favorable and unfavorable changes occurred in the children’s playing, sleeping, eating, and hygiene habits during the COVID-19 pandemic. It has been determined that the children’s use of televisions, tablets, and phones increased during this period. Emotional problems such as boredom, fear, anxiety, tantrums, irritability, and impatience were found to be more common in children compared to the pre-pandemic period, together with behavioral problems such as non-obedience, desire to attract attention, aggression, excessive speaking, hyperactivity, conflicts between siblings, speaking loudly, and increased impulses. Conclusions: In line with the parental opinions, it is observed that the school closures, social isolation, and children’s inability to spend time with their peers affect the children particularly adversely. This study shows that children cannot burn their energy sufficiently due to their limited range of movement in the house. In addition, it is observed that some of the children had problems such as reluctance to sleep alone and fear of the dark from the beginning of the pandemic. It was found noteworthy that the children experienced fear and anxiety not only about the risk of being infected with the virus but also about losing their parents.
Optical emissions associated with narrow bipolar events in radio signals from thunderstorm clouds penetrating into the stratosphere
Authors: Liu Feifan , Lu Gaopeng , Neubert Torsten , Lei Jiuhou , Chanrion Olivier , Østgaard Nikolai , Li Dongshuai , Luque Alejandro , Vázquez Francisco J. Gordillo , Reglero Víctor , Lyu Weitao , Zhu Baoyou 
Published: March 2021

Abstract
Narrow bipolar events (NBEs) are signatures in radio signals from thunderstorms observed by ground-based receivers. They are electromagnetic waves radiated by impulsive currents of electrical discharges. They come with two polarities, the positive that brings negative charge aloft, and the negative, that brings negative charge towards the earth. The sources of negative NBEs are at the very top of thunderclouds, and positive NBEs are at the upper levels, but inside the clouds. NBEs may occur at the onset of lightning, but the discharge process is not well understood. Here, we present spectral measurements by the Atmosphere-Space Interactions Monitor (ASIM) on the International Space Station that are associated with nine negative and three positive NBEs observed by a ground‐based array of receivers at the closest distance of about 100 km. We found that both negative and positive NBEs are associated with emissions at 337 nm with weak or no detectable emissions at 777.4 nm, suggesting that NBEs are associated with fast streamer breakdown. The rise times of the emissions for negative NBEs are about 10 µs, consistent with source locations at cloud tops where photons undergo little scattering by cloud particles, and for positive NBEs are ~ 1 ms, consistent with locations deeper in the clouds. For negative NBEs, the amplitude of the emissions is almost linearly correlated with the peak current of the associated NBEs. Our findings suggest that ground-based observations of radio signals provide a new means to measure the occurrences and strength of cloud-top discharges with implications for studies of perturbations of greenhouse gas concentrations at the tropopause.
Comparative Study of Regional Development in Tehran and Sistan and Baluchestan
Authors: PILEHVAR ali asghar , Harasani Amin 
Published: March 2021

Abstract
The purpose of this article is to identify and analyze the extent of regional differences in terms of human development and economic development indices. In this study, the level of national-regional development in the two provinces of Tehran and Sistan and Baluchestan is measured by the above two indices to highlight discrepancies in regional development in Iran. In this applied research, a descriptive-analytical method has been adopted. The research data were obtained from the official Census of 2011 as well as the last official Census in 2016. The economic index was measured by Izard model and the conclusions were informed by the human development index. The results manifest that the studied indices have been affected by geographical factors and micro/macro policies of the government in the four decades since the 1979 Revolution, contributing to the widening of regional development gap. The HDI was 0.720 in Tehran and 0.494 in Sistan and Baluchestan. Also, the per capita income index of Tehran and Sistan and Baluchestan were 0.497 and 269.0, respectively, which indicates a marked difference. As for the average years of study, the index of Tehran (0.780) was nearly two-fold higher than that of Sistan and Baluchestan (0.439). However, the life expectancy index exhibited a smaller difference than the overall average. The results of the research based on the Izard model also demonstrate that Tehran and Sistan and Baluchestan with an average of 126% and 172% in economic sectors are above the national average (112%), the only difference being that the development process in Sistan and Baluchestan is changing rapidly.
Assessment of Life Cycle Environmental Benefits in Monosodium Glutamate Production in China
Authors: Yu Fei , Guan Dan , Zhang Zudong , Zhao Lei , Zang Lihua 
Published: March 2021

Abstract
Purpose

As a process with high water consumption, high energy consumption and high pollutant discharge, monosodium glutamate (MSG) production has long attracted the attention of environmental protection authorities. In view of its significant environmental influence and enormous output, life cycle environmental impacts of MSG should be assessed to identify environmental hot spots and promote environmental improvements, and to update the life cycle inventory database of MSG production.
Methods

A life cycle assessment (LCA) framework is conducted to evaluate the environmental impacts of MSG production by the use of eBalance software. In addition, the environmental impacts associated with the application of typical cleaner production techniques over the past decade in MSG production are evaluated by LCA to quantitatively demonstrate the importance of implementing cleaner production measures.
Results and discussion

The results indicate that maize planting and tail liquid utilization have the largest environmental impacts within the life cycle of MSG. The former is the most important driver of impacts such as eutrophication (90.37%), respiratory inorganic formation (34.04%) and primary energy demand (26.60%). The latter contributes to 96.72% of the photochemical oxide formation and 20.12% of the global warming potential. In addition, glutamate extraction and refining processes also contribute significantly to the global warming potential, acidification and respiratory inorganics. The results also show that the application of cleaner production technologies over the past decade has driven the reductions in photochemical oxide formation (92.40%) and water use (66.00%).
Conclusion

Based on the research findings, several suggestions, such as green raw material utilization, green supply chain construction and industrial symbiosis network establishment, are proposed to further reduce the overall environmental impacts of MSG.
Research on Deep-hole Drilling Quality of High-strength Steel With Slender Gun Drill
Authors: Liang Jiabin , Jiao Li , Yan Pei , Cheng Minghui , Qiu Tianyang , Wang Xibin 
Published: March 2021

Abstract
There are a lot of problems exist in the processing of long and thin deep hole gun drilling of high strength steel, such as insufficient of the machining mechanism and characteristics of gun drilling, difficulty in selecting machining parameters, unknown influence mechanism of machining parameters on drilling force, drilling temperature and machining quality. In this paper, 42CrMo high strength steel is selected as the workpiece material. A numerical model of cutting force is established based on the mechanism of gun drill, and then the finite element simulation and processing test are carried out. The results show that the cutting force decreases with the increase of cutting speed, and increases with the increase of feed speed; the error between the theoretical and actual value is less than 10%. Cutting speed and feed speed have a great influence on machining quality, and the cutting fluid pressure mainly affects the surface roughness.
Aquisphaera Insulae Sp. Nov., a New Member in Isosphaeraceae Isolated From the Floating Island of Loktak Lake and Emended Description of the Genus Aquisphaera
Authors: Kumar Gaurav , L Lhingjakim Khongsai , U Jagadeeshwari , A Shabbir , Kumar Dhanesh , Kashif Gulam Mohammad , Ch Sasikala , Ramana Ch. Venkata 
Published: March 2021

Abstract
Strain JC669T was isolated from a floating island of Loktak lake, Manipur, India and shared highest 16S rRNA gene sequence identity with Aquisphaera giovannonii OJF2T. The strain is an aerobe, Gram-stain-negative, yellowish orange coloured, non-motile, NaCl intolerant, spherical to oval shaped, grows in single or aggregates and produce structures which appear like fruiting bodies. Strain JC669T grows well up to pH 9.0, has MK6 as respiratory quinone, C18:1ω9c, C16:0 and C18:0 as major fatty acids and phosphatidylcholine, an unidentified amino lipid, an unidentified choline lipid (UCL) and six unidentified lipids (UL1,2,3,4,5,6) as polar lipids. The genome size of strain JC669T is 10.04 Mbp and genomic G+C content of 68.5 mol%. Based on phylogenetic, polyphasic including genomic analyses support strain JC669T as a novel species of the genus Aquisphaera, for which we propose the name Aquisphaera insulae sp. nov. Type strain is JC669T ( =KCTC 72672T = NBRC 114306T).