scholarly journals Insights into the Intrinsic Factors Affecting the NIR Reflectance Based on Rylene Diimide Molecules

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5269
Author(s):  
Weili Zeng ◽  
Yujie Song ◽  
Jianning Zhang ◽  
Hong Chen ◽  
Ming Liu ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Molecular Structures ◽  
Heat Radiation ◽  
Clear Understanding ◽  
Factors Affecting ◽  
Intrinsic Factors ◽  
Alkyl Groups ◽  
Amine Groups

A clear understanding of the relationships between molecular structure and NIR reflectance (700–2500 nm) behavior is important and highly desirable for developing appropriate NIR-reflective materials to combat NIR heat radiation from sunlight. In this research, three groups of imide-based compounds have been adopted to investigate the influence of the intrinsic molecular structures on the NIR-reflective properties. It is found out that for the compounds with alkyl groups, the NIR reflectance will increase as the degree of the conjugated backbone increases, especially for the reflectance from 1750 nm to 2500 nm. In addition, despite that the alkyl or amine groups deteriorate the NIR reflectance, the NIR reflectance varies within a certain interval and the isomers with branched alkyl groups show identical or smaller NIR reflectance than those of isomers with linear alkyl groups. For different compounds, crystallinity seems to almost have no relationship with their NIR reflectance.

scholarly journals GENERAL CHARACTERISTICS OF INFLUENZA VIRUS A MOLECULAR STRUCTURE

2018 ◽  
pp. 13-19
Author(s):  
Deryabina Nina ◽  
Gritsenko Dilyara ◽  
Galiakparov Nurbol
Keyword(s):  
Molecular Structure ◽  
Influenza Virus ◽  
Binding Sites ◽  
Molecular Structures ◽  
Effective Vaccine ◽  
Clear Understanding ◽  
Human Species ◽  
The World ◽  
Critical Regions ◽  
Effective Drugs

The influenza virus is one of the most abundant viruses in the world. It causes both mild seasonal infections and severe pandemics killing thousands of people and mammals. Two main extracellular receptors – neuraminidase (NA) and hemagglutinin (HA) are responsible for infection symptoms development and spread. Error-prone RNA-polymerase incorporates mutations into both neuraminidase and hemagglutinin per replication cycle, which complicates the development of highly effective drugs against animal influenza. Incorporated mutations are also involved in the transition of influenza from animal to human species and vice versa. Transited influenza subtypes are the most dangerous, because it is unpredictable now, where the mutation might arise. However, it starts to become clear, which molecular regions are the most common for the mutation to occur. This article revises the molecular structure of influenza extracellular receptors, including critical regions of receptors binding sites and susceptible mutation sites. The clear understanding of molecular structures and critical regions of HA and NA might facilitate the development of an effective vaccine and/or drug development.

Factors Affecting Molecular Self-Assembly and Its Mechanism

2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan
Keyword(s):  
Self Assembly ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Molecular Structures ◽  
Polymer Science ◽  
New Approach ◽  
Factors Affecting ◽  
Dna Structures ◽  
Self Assembling ◽  
Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

scholarly journals Clinical analysis of tracheobronchial foreign body aspiration in children: a focus on external and intrinsic factors

BMC Surgery ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Weigang Gan ◽  
Ning Xiao ◽  
Yiyuan Feng ◽  
Danmei Zhou ◽  
Juanjuan Hu ◽  
...  
Keyword(s):  
Foreign Body ◽  
Pediatric Patients ◽  
Treatment Delay ◽  
Rigid Bronchoscopy ◽  
Foreign Body Aspiration ◽  
External Factors ◽  
Factors Affecting ◽  
Intrinsic Factors ◽  
Common Location ◽  
Tracheobronchial Foreign Body

Abstract Background Tracheobronchial foreign body aspiration (TFBA) is a critical disease in children and is extremely dangerous, even life-threatening. The factors affecting the occurrence and prognosis of TFBA are complex. The purpose of this study is to examine the external and intrinsic factors affecting clinical features of TFBA in West China and propose potential effective intervention measures. Methods We retrospectively analyzed the clinical data of pediatric patients diagnosed with TFBA with foreign bodies (FBs) removed by rigid bronchoscopy under general anesthesia at the otolaryngology department from December 2017 to November 2018. The data included age, sex, clinical symptoms, type and location of FB, guardians, prehospital duration and residence of these pediatric patients. Results The ratio of males (72) to females (53) was 1.4:1. Children aged from 1 to 3 years accounted for 76% (95/125) of patients. Cough, continuous fever and dyspnea were the primary symptoms. The right primary bronchus was the most common location of FB detection by rigid bronchoscopy (67 cases, 53.6%). Organic FBs were most common in our study. Guardians of patients significantly differed in the rural (parents 16, grandparents 31) and urban (parents 52, grandparents 26) groups (χ2 = 12.583, p = 0.000). More children in the rural group than in the urban group had a treatment delay longer than 72 h. More children in the group with no history of FB aspiration (12, 25%) than in the group with prior FB aspiration had a treatment delay longer than 72 h. Conclusion Pediatric TFBA is a common emergency in otolaryngology. Age, sex, tracheobronchial anatomy and other physiological elements were defined as intrinsic factors, while guardians, residence, FB species and prehospital time were defined as external factors of TFBA. External and intrinsic factors both influence the occurrence and progression of TFBA. It is extremely important to take effective measures to control external factors, which can decrease morbidity and mortality.

scholarly journals A Raman, SERS and UV-circular dichroism spectroscopic study of N-acetyl-l-cysteine in aqueous solutions

2019 ◽  
Vol 43 (38) ◽  
pp. 15201-15212 ◽  
Author(s):  
R. A. Cobos Picot ◽  
M. Puiatti ◽  
A. Ben Altabef ◽  
R. J. G. Rubira ◽  
S. Sanchez-Cortes ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Circular Dichroism ◽  
Aqueous Solutions ◽  
Spectroscopic Study ◽  
Electronic Properties ◽  
Structural Properties ◽  
Amine Groups ◽  
Circular Dichroïsm

The aim of this work is to evaluate the vibrational and structural properties of N-acetyl-l-cysteine (NAC), and its molecular structure and electronic properties in relation to the action of thiol and amine groups at different pH.

Metaphoric chains

2021 ◽  
Vol 19 (2) ◽  
pp. 273-298
Author(s):  
Sakineh Navidi-Baghi ◽  
Ali Izanloo ◽  
Alireza Qaeminia ◽  
Alireza Azad
Keyword(s):  
Molecular Structure ◽  
Conceptual Metaphor ◽  
Previous Literature ◽  
Molecular Structures ◽  
Conceptual Metaphor Theory ◽  
Metaphor Theory ◽  
Different Types ◽  
New Form

Abstract The molecular structure of a complex metaphor comprises two or more atomic metaphorical parts, known as primary metaphors. In the same way, several molecular structures of metaphors may combine and form a mixture, known as mixed metaphors. In this study, different types of metaphoric integrations are reviewed and illustrated in figures to facilitate understanding the phenomena. Above all, we introduce double-ground metaphoric chain, a new form of metaphoric integration that has not been identified in the previous literature. Also, a distinction is made between single-ground and double-ground metaphoric chains. In the former, which has already been introduced, two basic metaphors are chained with the same form and have the same ground, while the latter includes two chained metaphors, one main metaphor plus a supportive one, with different grounds. In this analysis, we benefited from Conceptual Metaphor Theory (CMT) to analyse double-ground metaphoric chains. This study suggests that each metaphoric integration leads to a multifaceted conceptualization, in which each facet is related to one of the constituent micro-metaphors.

scholarly journals Factors affecting the cooking quality of stored carioca beans (Phaseolus vulgaris)

2021 ◽  
Vol 33 (4) ◽  
pp. 43-56
Author(s):  
Juliana Aparecida Correia Bento ◽  
Karen Carvalho Ferreira ◽  
Priscila Zaczuk Bassinello ◽  
B. Dave Oomah
Keyword(s):  
Storage Time ◽  
Scientific Literature ◽  
Cooking Quality ◽  
Market Value ◽  
Cooking Time ◽  
Factors Affecting ◽  
Intrinsic Factors ◽  
Culinary Quality ◽  
Technological Quality

The culinary quality of carioca beans is related to their market value and consumer acceptability. The depreciation of the cooking/technological quality of the product occurs mainly because of the integument browning and the longer cooking time of the grains, which are influenced by the storage time and conditions. The loss of culinary quality reduces the market value of carioca beans because consumers reject darkened grains that are attributed to a longer cooking time. As a result, cooking time (resistance to cooking), the color of the integument, and the texture of the cooked beans are determinant factors in the acceptance of carioca bean cultivars. The browning of the grain integument and the cooking time mainly depends on the environmental conditions, storage time, the tegument of each genotype, and the chemical and physical properties of the cotyledons. Therefore, this review aims to survey the scientific literature on the extrinsic and intrinsic factors that affect the culinary quality of carioca beans.

scholarly journals Zagreb Connection Index of Drugs Related Chemical Structures

2020 ◽  
Vol 11 (4) ◽  
pp. 11920-11930
Keyword(s):  
Molecular Structure ◽  
Structure Analysis ◽  
Topological Indices ◽  
Molecular Structures ◽  
Connection Number ◽  
Chemical Structures ◽  
Molecular Structure Analysis

Topological indices are used to test the medicine and pharmacology characteristics of drugs and their molecular structures. The modified first Zagreb connection number index is defined to be used in the analysis of drug structures. In this paper, by means of drug molecular structure analysis and vertex partitioning method, we compute the modified first Zagreb connection number index of graphene, polyomino chains, and Benzenoid systems, etc. These structures are used widely in molecular drug graphs.

scholarly journals Integrating Chemical Crystallography into Advanced Undergraduate Laboratories

2014 ◽  
Vol 70 (a1) ◽  
pp. C1382-C1382
Author(s):  
Joseph Tanski
Keyword(s):  
Molecular Structure ◽  
Undergraduate Students ◽  
Scientific Journal ◽  
Molecular Structures ◽  
Module Structure ◽  
Spectroscopic Techniques ◽  
X Ray Crystallography ◽  
Chemical Crystallography ◽  
Structure Of Molecules ◽  
Student Projects

As scientific educators, it is important to mentor students in using state-of-the-art instrumentation and in the communication of new knowledge. Just as chemical crystallography and complimentary spectroscopic techniques such as NMR can be fast, effective tools to experimentally determine the structure of molecules and enhance students learning of molecular structure, they can also provide an inspiring opportunity for students to write short, scientific journal style reports that can be edited and published in collaboration with a mentor. This contribution will focus on incorporating X-ray crystallography into an advanced undergraduate integrated laboratory class as part of a discovery based exercise where the students do not know the identity of their small molecule organic compound, and the publication of the resulting crystal structures. The structures of some recently published examples are shown below. With examples of past student projects and published structures, topics will include: sample choice, the discovery based molecular structure determination lab module, structure validation, analysis and discussion of intermolecular interactions such as hydrogen bonding, π-stacking, halogen-halogen interactions, and C-H···X (X = O, N, halogen) interactions, and the writing of descriptions of crystal and molecular structures for publication in collaboration with undergraduate students. This work was supported by grants from the U.S. National Science Foundation, No. 0521237 & 0911324.

scholarly journals Detection and Investigation of Some Properties of the Regulators of Antibiotic Biosynthesis Produced by Streptomyces Strains S. sp. AN26 and S. sp. B35

2021 ◽  
Vol 83 (6) ◽  
pp. 49-54
Author(s):  
B.P. Matselyukh ◽  
Keyword(s):  
Molecular Structure ◽  
Nmr Spectroscopy ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Transcriptional Regulators ◽  
Signaling Molecules ◽  
Molecular Structures ◽  
Antibiotic Biosynthesis ◽  
Future Studies ◽  
Layer Chromatography

The aim of this work was the isolation, purification and some properties investigation of two regulators of antibiotic biosynthesis of streptomycetes. Methods includes extraction of regulators from agar cultures and their concentration by vacuum rotary evaporator, thin layer chromatography and spectrophotometry. Results. Two strains of streptomycetes AN26 and B35 isolated from soils of different regions of Ukraine produce the regulators restoring the landomycin E biosynthesis and sporulation in mutant strain Streptomyces globispoprus 1912-B2. Both regulators were purified by thin layer chromatography and have the same Rf 0.69. Absorption curves of regulators were established by means of spectrophotometry. Maxima of absorption of regulators were 232.5 nm. The next study of the isolated regulators by means of NMR will give the possibility to elucidate their molecular structures. Conclusions. It is shown that two strains of streptomycetes isolated from the soils of Askania Nova and Brovary produce transcriptional regulators such as signaling molecules, which, like A-factor, restore the biosynthesis of antibiotics landomycin E and streptomycin in test strains S. globisporus 1912-B2 and S. griseis 1439, respectively. In terms of absorption maxima, they are similar and differ from similar indicators of known regulators of streptomycetes. It is possible that these compounds belong to new, not yet described signaling molecules, and the answer to this question will give future studies of their molecular structure by NMR spectroscopy.

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