There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Sustainable economic and industrial growth requires safe, sustainable resources of energy. For the future re-arrangement of a sustainable economy to biological raw materials, completely new approaches in research and development, production, and economy are necessary. The ‘first-generation’ biofuels appear unsustainable because of the potential stress that their production places on food commodities. For organic chemicals and materials these needs to follow a biorefinery model under environmentally sustainable conditions. Where these operate at present, their product range is largely limited to simple materials (i.e. cellulose, ethanol, and biofuels). Second generation biorefineries need to build on the need for sustainable chemical products through modern and proven green chemical technologies such as bioprocessing including pyrolysis, Fisher Tropsch, and other catalytic processes in order to make more complex molecules and materials on which a future sustainable society will be based. This review focus on cost effective technologies and the processes to convert biomass into useful liquid biofuels and bioproducts, with particular focus on some biorefinery concepts based on different feedstocks aiming at the integral utilization of these feedstocks for the production of value added chemicals.

http://staff.cimap.res.in/PublicationFiles/Renew_Sustain_Energ_Rev_14_578.pdf

Production of first and second generation biofuels: A comprehensive review

Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S. A. S. Nagar,Mohali, Punjab-160 062, India, Institute of Biochemistry, Faculty of Medicine, Polytechnic University, Via Ranieri 67, IT-60100 Ancona, Italy,Green Biotechnology Research Group, The Special Division for Human Life Technology, National Institute of Advanced Industrial Science andTechnology, 1-8-31 Midorigaoka, Ikeda, Osaka-563-8577, Japan, and Department of Medicinal Chemistry & Natural Products,The Hebrew University of Jerusalem, School of Pharmacy-Faculty of Medicine, Jerusalem 91120, IsraelReceived March 2, 2004

Chitosan chemistry and pharmaceutical perspectives.

Sophorolipids are one of the most important microbial biosurfactants, because of their large-scale production and applications developed so far in the fields of detergency, microbiology, cosmetics or environmental science. However, the structural variety of native sophorolipids is limited/restricted, a limiting fact for the development of new properties and their potential applications. In their open acidic form, C18:1 sophorolipids (SL) are classically composed of a sophorose headgroup and a carboxylic acid (COOH) end-group. The carboxyl group gives them unique pH-responsive properties, but they are a poorly-reactive group and their charge can only be negative. To develop a new generation of pH-responsive, positively-charged, SL and to improve their reactivity for further functionalization, we develop here SLs with an amine (-NH2) or terminal alkyne (-C$\not\equiv$CH) end-group analogues. The amine group generates positively-charged SL and is more reactive than carboxylic acids, e.g. towards aldehydes; the alkyne group provides access to copper-based click chemistry. In this work, we synthesize (C18:1) and (C18:0) --NH2 and (C18:1) -C$\not\equiv$CH sophorolipid derivatives and we study their self-assembly properties in response to pH and/or temperature changes by means of static and dynamic light scattering, small angle (X-ray, neutron) scattering and cryogenic electron microscopy. Monounsaturated aminyl SL-C18:1-NH2 sophorolipids form a micellar phase in their neutral form at high pH and a mixed micellar-bilayer phase in their positively-charged form at low pH. Saturated aminyl SL-C18:0-NH2 sophorolipids form a micellar phase in their charged form at low pH and a twisted ribbon phase in their neutral form at high pH and monounsaturated alkynyl SL-C18:1-C$\not\equiv$CH sophorolipids form a main micellar phase at T> 51.8{\textdegree}C and a twisted ribbon phase at T< 51.8 {\textdegree}C.

Synthesis and self-assembly of aminyl and alkynyl substituted sophorolipids.

Often, different types of contaminants in wastewater are suspected of adversely affecting the treatment efficiency of a wastewater treatment plant (WWTP). Therefore, it is essential to study the effects of newly synthesized substances on the activity of activated sludge microorganisms. The aim of this study was to determine the effect of innovative biosurfactants, i.e., sophorolipids quaternary ammonium salts (SQAS), and three common micropollutants (MPs), i.e., diclofenac (DCP), 17α-ethynylestradiol (EE2), and 4-nonylenol (4-NP), on the biochemical activity of activated sludge microorganisms. The effect of all tested substances was more significant on nitrite-oxidizing bacteria (NOB) than on ammonia-oxidizing bacteria (AOB), and least on the respiratory activity of heterotrophic organisms (HET). SQAS inhibited nitrification even at the lowest concentration tested (5 mg L−1) and the inhibition degree was in the range of 37% to 78%; at the highest concentration of SQAS studied (160 mg L−1), it was about 45–96%. In most cases, the degree of inhibition increased when the SQAS concentration approached 80–160 mg L−1. MPs influenced the activity of nitrifiers to a lower extent than SQAS. The inhibition degree varied from 25% to 75%, depending on the micropollutant tested and its concentration.

https://www.mdpi.com/2071-1050/13/13/7417/pdf

Effect of Newly Synthesized Salts and Three Common Micropollutants on the Biochemical Activity of Nitrifiers

The amount of known chemical reactions is ever increasing. By now, databases exist containing millions of reactions and related data. While being an invaluable source of knowledge, the sheer quantity of data has long surpassed the conceivability of the human mind. In order to put this data to good use, for example for reaction network generation or retro-synthetic analysis, tools and methodologies are required to interpret and access this data efficiently. The novel methodology implemented in the reaction network generator Genesys has been specifically designed to automatically analyze reactions and extract information on the reaction mechanism in order to construct reaction templates for future automated mechanism generation. The capabilities of the method are tested on a set of pyrolysis related reactions. The set of 110 reactions was analyzed and reduced to a set of 44 reaction families that was fully compatible with Genesys.

https://biblio.ugent.be/publication/8537886/file/8537887.pdf

Automated reaction family generation and analysis using cheminformatics

Rearrangement of α,δ-Dichloroaldimines to 2- Formylpyrrolidines: α,α-Azacyclobisalkylation of Aldehydes

α-Chloro acylphosphonates and α,α′-dichloro bisacylphosphonates were prepared in situ by chlorination of acylphosphonates and bisacylphosphonates, respectively, using sulfuryl chloride. Subsequently, they were cleaved to the corresponding α-chlorinated or α,α′-dichlorinated (di)carboxylic acids with a hydrogen peroxide–sodium bicarbonate system. Performing the cleavage with an alcohol or an amine yielded the corresponding α-chlorinated esters and α-chlorinated amides, respectively.

Christian V. Stevens

Papers

Synthesis and self-assembly of aminyl and alkynyl substituted sophorolipids.

Effect of Newly Synthesized Salts and Three Common Micropollutants on the Biochemical Activity of Nitrifiers

Automated reaction family generation and analysis using cheminformatics

Rearrangement of α,δ-Dichloroaldimines to 2- Formylpyrrolidines: α,α-Azacyclobisalkylation of Aldehydes

Use of Acylphosphonates for the Synthesis of α‐Chlorinated Carboxylic and α,α′‐Dichloro Dicarboxylic Acids and Their Derivatives.