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2022 ◽  
Vol 14 (2) ◽  
pp. 651
Author(s):  
Stuart Gee ◽  
Andre Brown

Prefabricated timber component-based systems are the most prevalent industrialised system used to build housing. Along with many other countries, the UK has invested in different types of factory-based prefabrication systems as a means of increasing productivity and enhancing quality. In more recent decades, prefabrication has become part of a series of ‘modern methods of construction’ employed for, and aimed at, delivering sustainable and efficient construction. However, certain pragmatic issues remain. The industry is cyclical, and during periods of declining resources, skills and technical development can be lost. Additionally, factory-based prefabrication requires substantial initial investment and an appropriate local workforce. To help address these issues, this paper presents the concept of an alternative method of production and assembly that takes a different approach to traditional industrialised systems that involve large investments and fixed-location factories. The proposition presented in this paper is that it is possible to design and develop a small, low cost, portable micro-factory that can be taken to a temporary location or construction site, where it can then be used to construct prefabricated closed panels. We describe the development of a working prototype, effectively a micro-factory, along with its potential advantages over a fixed facility.


Synlett ◽  
2022 ◽  
Author(s):  
Byungjun Kim ◽  
Yongjae Kim ◽  
Sarah Yunmi Lee

AbstractBecause of the versatility of chiral 1,5-dicarbonyl structural motifs, the development of stereoselective Michael additions of arylacetic acid derivatives to electron-deficient alkenes is an important challenge. Over recent decades, an array of enantio- and diastereoselective methods of this type have been developed through the use of chiral organocatalysts. In this article, three distinct strategies in this research area are highlighted. Catalytic generation of either a chiral iminium electrophile (iminium catalysis) or a chiral enolate nucleophile (Lewis­ base catalysis) has allowed the efficient construction of stereogenic C–C bonds. We also introduce a synergistic catalytic approach involving the merger of these two catalytic cycles that provides selective access to all four stereoisomers of products with vicinal stereocenters.1 Introduction2 Iminium Catalysis3 Lewis Base Catalysis4 Synergistic Organocatalysis5 Summary


2021 ◽  
Vol 12 (1) ◽  
pp. 63
Author(s):  
Ahsan Afraz ◽  
Majid Ali

Currently, banana fiber composites have received wide attention because of their ecofriendly properties. The overall aim of this study is to prove banana fiber as an eco-efficient construction material by checking the behavior of banana fiber-reinforced concrete during flexural loading. The length of fiber is kept 50 mm and a fiber content of 5% by the weight of cement was used for preparing banana fiber reinforced concrete. It is shown from the results that the flexural toughness index (FTI) that has a vital role in sustainable concrete increased while the modulus of rupture (MOR) of banana fiber reinforced concrete decreased as compared to ordinary concrete.


2021 ◽  
Author(s):  
Xiaolei Li ◽  
Jicheng Wu ◽  
Weiping Tang

Human glycans are primarily composed of nine common sugar building blocks. On the other hand, several hundred monosaccharides have been discovered in bacteria and most of them are not readily available. The ability to access these rare sugars and the corresponding glycocon-jugates can facilitate the studies of various fundamentally important biological processes in bacteria, including interactions between microbiota and the human host. Many rare sugars also exist in a variety of natural products and pharmaceutical reagents with significant biological activi-ties. Although methods have been developed for the synthesis of rare monosaccharides, most of them involve lengthy steps. Herein we report an efficient and general strategy that can provide access to rare sugars from commercially available common monosaccharides via a one-step Ru(II)-catalyzed and boron-mediated selective epimerization of 1,2-trans-diols to 1,2-cis-diols. The formation of boronate esters drives the equilibrium towards 1,2-cis-diol products, which can be immediately used for further selective functionalization and glycosylation. The utility of this strategy was demonstrated by the efficient construction of glycoside skeletons in natural products or bioactive compounds.


Molbank ◽  
10.3390/m1308 ◽  
2021 ◽  
Vol 2022 (1) ◽  
pp. M1308
Author(s):  
Yuliya E. Ryzhkova ◽  
Oleg I. Maslov ◽  
Michail N. Elinson

Dimethyl sulfoxide (DMSO) is widely used as a solvent in organic synthesis and in pharmacology because of its low cost, stability, and non-toxicity. Multicomponent reactions are a powerful synthetic tool for the rapid and efficient construction of complicated molecular frameworks. In this communication, the multicomponent transformation of salicylaldehyde, malononitrile dimer, and dimethyl malonate in DMSO at room temperature was carefully investigated to give dimethyl 2-(2,4-diamino-3-cyano-5H-chromeno[2,3-b]pyridin-5-yl)malonate with good yield. The structure of the new compound was established by means of elemental analysis and mass, nuclear magnetic resonance, and infrared spectroscopy.


2021 ◽  
Vol 16 (6) ◽  
pp. 701-707
Author(s):  
Khalid A. Mohammed ◽  
Ali I. Mansi ◽  
Suha M. Salih

Over the last two decades, the rapid and continued deterioration of the transportation network has been regarded as a major issue. There are many measures that can be taken to reduce this deterioration and improve road specifications, including improving road design, using higher quality materials, and using more efficient construction methods. This study is concerned with three principles: including investigating the impact of using waste paste on the rheological properties of bitumen; the environmental pollution that is a global problem; and the economic benefits as a result of the reusing of waste materials such as corks to produce new reusable materials like Modified-Asphalt. In this research, cork has been melted by thinner and mixed with asphalt to get a good paste with weight percentages of 1%, 3%, 5%, and 7%. After conducting the necessary tests on the samples, it was found that the addition of waste paste to virgin bitumen has softened the bitumen by decreasing the hardness and adhesiveness of the bitumen by increasing penetration with increasing cork paste content. The findings show that the current procedure can be used in cold regions because it requires less hard asphalt than that used in hot regions. It can also be used with natural asphalt, like natural rock asphalt, in various percent to give asphalt with suitable properties for use in roofing and paving roads.


2021 ◽  
Author(s):  
Jamshed Khan ◽  
Marek Kokot ◽  
Sebastian Deorowicz ◽  
Rob Patro

The de Bruijn graph has become a key data structure in modern computational genomics, and of keen interest is its compacted variant. The compacted de Bruijn graph provides a lossless representation of the graph, and it is often considerably more efficient to store and process than its non-compacted counterpart. Construction of the compacted de Bruijn graph resides upstream of many genomic analyses. As the quantity of sequencing data and the number of reference genomes on which to perform these analyses grow rapidly, efficient construction of the compacted graph becomes a computational bottleneck for these tasks. We present Cuttlefish 2, significantly advancing the existing state-of-the-art methods for construction of this graph. On a typical shared-memory machine, it reduces the construction of the compacted de Bruijn graph for 661K bacterial genomes (2.58 Tbp of input reference genomes) from about 4.5 days to 17—23 hours. Similarly on sequencing data, it constructs the graph for a 1.52 Tbp white spruce read set in about 10 hours, while the closest competitor, which also uses considerably more memory, requires 54—58 hours. Cuttlefish 2 is implemented in C++14, and is available as open-source software under a BSD-3-Clause license at https://github.com/COMBINE-lab/cuttlefish.


Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2502
Author(s):  
Maki Watanabe ◽  
Yuya Nishikawaji ◽  
Hirotaka Kawakami ◽  
Ken-ichiro Kosai

Gene therapy is currently in the public spotlight. Several gene therapy products, including oncolytic virus (OV), which predominantly replicates in and kills cancer cells, and COVID-19 vaccines have recently been commercialized. Recombinant adenoviruses, including replication-defective adenoviral vector and conditionally replicating adenovirus (CRA; oncolytic adenovirus), have been extensively studied and used in clinical trials for cancer and vaccines. Here, we review the biology of wild-type adenoviruses, the methodological principle for constructing recombinant adenoviruses, therapeutic applications of recombinant adenoviruses, and new technologies in pluripotent stem cell (PSC)-based regenerative medicine. Moreover, this article describes the technology platform for efficient construction of diverse “CRAs that can specifically target tumors with multiple factors” (m-CRAs). This technology allows for modification of four parts in the adenoviral E1 region and the subsequent insertion of a therapeutic gene and promoter to enhance cancer-specific viral replication (i.e., safety) as well as therapeutic effects. The screening study using the m-CRA technology successfully identified survivin-responsive m-CRA (Surv.m-CRA) as among the best m-CRAs, and clinical trials of Surv.m-CRA are underway for patients with cancer. This article also describes new recombinant adenovirus-based technologies for solving issues in PSC-based regenerative medicine.


Biosensors ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 506
Author(s):  
Hyewon Roh ◽  
Hwisoo Kim ◽  
Je-Kyun Park

Spheroid, a 3D aggregate of tumor cells in a spherical shape, has overcome the limitations of conventional 3D cell models to accurately mimic the in-vivo environment of a human body. The spheroids are cultured with other primary cells and embedded in collagen drops using hang drop plates and low-attachment well plates to construct a spheroid–hydrogel model that better mimics the cell–cell and cell–extracellular matrix (ECM) interactions. However, the conventional methods of culturing and embedding spheroids into ECM have several shortcomings. The procedure of transferring a single spheroid at a time by manual pipetting results in well-to-well variation and even loss or damage of the spheroid. Based on the previously introduced droplet contact-based spheroid transfer technique, we present a poly(dimethylsiloxane) and resin-based drop array chip and a pillar array chip with alignment stoppers, which enhances the alignment between the chips for uniform placement of spheroids. This method allows the facile and stable transfer of the spheroid array and even eliminates the need for a stereomicroscope while handling the cell models. The novel platform demonstrates a homogeneous and time-efficient construction and diverse analysis of an array of fibroblast-associated glioblastoma multiforme spheroids that are embedded in collagen.


2021 ◽  
Author(s):  
◽  
Armano Papageorge

<p>Since the beginning of the 20th century, modernism introduced to the world an architectural composite that consists of concrete, steel and glass. Heading into the 21st century, the use of these three materials has only expanded as it continues to be the most economically efficient means of construction. While digital technology in design and construction continues to evolve, the materials at which we construct architecture has remained the same. Given the rapid growth of the human population, new and more sustainable approaches to construction methodologies and materials need to be explored and utilised. This research will demonstrate the potential of freeform 3D printing as a sustainable and efficient alternative building method. It outlines contemporary digital design techniques including computation and simulation tools as a means to define and test this proposed building method including structural optimisation tools to create the most structurally efficient form from additive manufacturing. The computational methods described are then applied to a manufacturing process that includes a 6-axis robotic arm. The final result is a building methodology that supports a computational workflow from design conception to manufacture.</p>


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