Chain Linkages Research Articles

Restructuring Perceptions of Geographical Knowledge and Experience Among Learners Under a Concept Mapping Domain

Alexandra k Transfer quoted, “The best teachers are those who show you where to look, but don’t tell you what to see”. While teaching merely rests on art but it connotes into science wherein imaginative minds are ignited for knowledge. Pedagogy and enriched content are dependable solutions for effective teaching and learning. Real meaningful learning is the focus of modern teaching which follows a constructivist approach. Bygone are the days when the traditional lecture method was sufficient to teach the pupils. Advanced technologies have been the replacement of the monotonous lecture method in Geographic studies. The pupil now constructs their knowledge by engagement, exploration, explanation, elaboration and evaluation methods. Different pedagogical practices are involved, like the enquiry approach, reflective strategy, collaborative learning, etc., among which concept mapping is one of the important strategies applied in Geography teaching. It is a graphical organiser which connects links between the two or more concepts in some logical, sequential flows. Concept Mapping effectively assists in achieving the learning outcomes. Learning outcomes are the assessment standard that indicates the expected level of learning that learners should achieve for that particular class. Many concepts of Geography dealing with exhaustive knowledge about nature and processes in nature are prudently taught with the concept mapping approach. These maps make a vivid picture of illustrated concepts in learners minds assuring thus, a rigorous and long-lasting rationalisation of content knowledge. The paper highlights one of the robust, innovative strategy of modern pedagogy in Geographic studies where the chain linkages in concept mapping provide an enriching experience of learning nature and natural phenomena.

Low-density-lipoprotein-receptor-related protein 1 mediates Notch pathway activation.

The Notch signaling pathway controls cell growth, differentiation, and fate decisions, and its dysregulation has been linked to various human genetic disorders and cancers. To comprehensively understand the global organization of the Notch pathway and identify potential drug targets for Notch-related diseases, we established a protein interaction landscape for the human Notch pathway. By combining and analyzing genetic and phenotypic data with bioinformatics analysis, we greatly expanded this pathway and identified many key regulators, including low-density-lipoprotein-receptor-related protein 1 (LRP1). We demonstrated that LRP1 mediates the ubiquitination chain linkage switching of Delta ligands, which further affects ligand recycling, membrane localization, and stability. LRP1 inhibition led to Notch signaling inhibition and decreased tumorigenesis in leukemia models. Our study provides a glimpse into the Notch pathway interaction network and uncovers LRP1 as one critical regulator of the Notch pathway, as well as a possible therapeutic target for Notch-related cancers.

Utilization of waste chicken feather for the preparation of eco-friendly and sustainable composite

Waste material from a poultry farm, especially chicken feathers, is going to be a big concern for a clean environment as the quantity is mounting day by day. Just discarding waste chicken feathers are neither cost-effective nor eco-friendly. On the other hand, the upward demand for the synthetic polymer is also a huge obstacle in the way of a green environment. Synthetic polymers are not only responsible for polluting the environment but also hampering daily life. A significant challenge for a clean and sustainable environment is waste disposal as well as minimizing non-degradable polymers. In this research, we utilized discarded chicken feathers as a reinforcing agent and unsaturated polyester resin (UPR), synthetic polymer, as a matrix material for the preparation of composite through hand-lay-up technique. A number of percentages (2, 5, 7, 10, 12, and 15% by weight) of waste chicken feathers were added to the matrix for the enhancement of mechanical properties. The acquired results from the mechanical tests (tensile strength (TS), tensile modulus (TM), percentage elongation at break (EB), bending strength (BS), bending modulus (BM)) indicated that the 5 and 10% chicken feather fiber loading composites are the best percentages. The highest enhancements of TS, TM, BS, and BM are 64%, 64%, 103%, and 48% respectively for optimized composites. The Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) carried good evidence for mechanical bonding instead of chemical bonding between fiber and UPR. The composites showed the degradation of helix structure in thermogravimetry analysis (TGA) from the skeleton of chain linkage, and peptide bridges of fiber to decay keratin into CO2, H2S, and HCN.

A Study on Vegetable Export for the Economic Development of Bangladesh and Its Entrepreneurial Opportunities for Young Educated Bangladesh People

This study tries to explain the prevailing vegetable supply chain system in Bangladesh which impact on International Market linkages includes some markets, number of intermediaries, and involvement of Stakeholder. Next, it shows many limitations within the present supply chain where the issues of export of vegetable supply chain have discoursed thoroughly. Then, the influences of lack of effective supply chain linkages are discussed. The main difficulties met by the growers, Exporter, and negotiators were deficiency of money, Training, production, Packaging Knowledge, poor communication and transport services, lack of adequate storage services, lack of suitable market info, higher market tolls, deficiency of market facilities, etc. The growers and intermediaries also suggested some solutions to those difficulties. As vegetables are perishable products, the study provides an overview of the issues and solutions within the use of cargo space at the airport. The govt should take the required steps to undo these problems and thus extend the effectiveness of vegetable supply chain export marketing in Bangladesh. Here shows a proposed vegetable supply chain and policy level suggestion for International Market linkages. At present Bangladesh is in the demographic dividend. It includes a large number of educated unemployed. This study provides a detailed explanation of how to start a new business to grow as an entrepreneur. These people can play a significant role in the country's GDP by exporting vegetables from the country by obtaining export licenses and earning foreign exchange. DOI: 10.7176/RHSS/11-20-09 Publication date: October 31 st 2021

Effect of Molecular Structure on Electrochemical Phase Behavior of Phospholipid Bilayers on Au(111).

Lipid bilayers form the basis of biological cell membranes, selective and responsive barriers vital to the function of the cell. The structure and function of the bilayer are controlled by interactions between the constituent molecules and so vary with the composition of the membrane. These interactions also influence how a membrane behaves in the presence of electric fields they frequently experience in nature. In this study, we characterize the electrochemical phase behavior of dipalmitoylphosphatidylcholine (DPPC), a glycerophospholipid prevalent in nature and often used in model systems and healthcare applications. DPPC bilayers were formed on Au(111) electrodes using Langmuir-Blodgett and Langmuir-Schaefer deposition and studied with electrochemical methods, atomic force microscopy (AFM) and in situ polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS). The coverage of the substrate determined with AFM is in accord with that estimated from differential capacitance measurements, and the bilayer thickness is slightly higher than for bilayers of the similar but shorter-chained lipid, dimyristoylphosphatidylcholine (DMPC). DPPC bilayers exhibit similar electrochemical response to DMPC bilayers, but the organization of molecules differs, particularly at negative charge densities. Infrared spectra show that DPPC chains tilt as the charge density on the metal is increased in the negative direction, but, unlike in DMPC, the chains then return to their original tilt angle at the most negative potentials. The onset of the increase in the chain tilt angle coincides with a decrease in solvation around the ester carbonyl groups, and the conformation around the acyl chain linkage differs from that in DMPC. We interpret the differences in behavior between bilayers formed from these structurally similar lipids in terms of stronger dispersion forces between DPPC chains and conclude that relatively subtle changes in molecular structure may have a significant impact on a membrane's response to its environment.

Mechanism of activation and regulation of deubiquitinase activity in MINDY1 and MINDY2

SummaryOf the eight distinct polyubiquitin (polyUb) linkages that can be assembled, the roles of K48-linked polyUb (K48-polyUb) are the most established, with K48-polyUb modified proteins being targeted for degradation. MINDY1 and MINDY2 are members of the MINDY family of deubiquitinases (DUBs) that have exquisite specificity for cleaving K48-polyUb, yet we have a poor understanding of their catalytic mechanism. Here, we analyze the crystal structures of MINDY1 and MINDY2 alone and in complex with monoUb, di-, and penta-K48-polyUb, identifying 5 distinct Ub binding sites in the catalytic domain that explain how these DUBs sense both Ub chain length and linkage type to cleave K48-polyUb chains. The activity of MINDY1/2 is inhibited by the Cys-loop, and we find that substrate interaction relieves autoinhibition to activate these DUBs. We also find that MINDY1/2 use a non-canonical catalytic triad composed of Cys-His-Thr. Our findings highlight multiple layers of regulation modulating DUB activity in MINDY1 and MINDY2.

A Portrait of Global Value Chain Linkages of Indian Manufacturing

This article provides an overview of India’s participation in global value chains (GVCs). Using multiple databases at the aggregate and industry levels, this article documents the trends in GVC participation of India during the last three decades. Authors further differentiate between India’s backward and forward integration at the country level before evaluating the industry-specific dynamics of GVCs in India. In this study, authors also shed light upon the rising servicification of Indian manufacturing, and highlight the importance of services’ value addition in promoting GVC integration of India. JEL Codes: F1, F15, D57

Global value chain linkages and domestic value-added content: Empirical evidence

PurposeThis paper aims to examine the relationship between global value chains (GVCs) and domestic value-added content (DVA) in a panel of 58 countries for the period 2005–2015.Design/methodology/approachFirst, the authors quantify the refined measures of GVC linkages by using the Borin and Mancini (2019) decomposition technique. Second, the authors apply the feasible generalised least squares method to test the relationship between GVCs and DVA empirically.FindingsFirst, the authors find that GVC links are crucial to the enhancement of DVA. Second, a study at the sectoral level reveals that GVC links in the primary sector raise DVA whilst reducing DVA in the services sector. Third, the authors find that only upstream activities enhance value-added content. Fourth, the authors note the augmenting role played by national policies in mediating the gains associated with GVCs. Finally, the authors note that the outcomes associated with GVCs are consistent when the sample of countries is divided into groups based on income.Practical implicationsThe results lead us to urge policymakers to promote greater integration of business activities into GVCs to reap their benefits.Originality/valueThis paper contributes to the research on the impact of GVCs on DVA by emphasising the significance of the types of GVC activities and policies that improve DVA.

직접생산 확인제도의 현황과 개선방안에 대한 연구

The purpose of this study is to examine the current status and problems of the direct production verification system, and to present improvement plans if improvement is needed. In order to deliver competitive products between SMEs in the public procurement market, a direct production verification certificate must be attached. This direct production verification system was introduced to solve the problem that real added value is not created by supplying the products of partner companies as they are. Therefore, it prevents the delivery of products from large corporations, imported products, and simple bidding arrangements, and provides opportunities for participation in the competition system among SMEs only for products that are directly produced. This is because the fundamental purpose of the direct production verification system is to strengthen the competitiveness of SMEs participating in the public procurement market and maximize the creation of added value of domestic companies. With regard to the direct production verification system, both positive and negative opinions coexist. First of all, on the positive side, first, the competition system among SMEs through direct production verification promotes technology-oriented competition and alleviates the impact of economic fluctuations in the event of a recession by expanding opportunities for start-ups. The competition system between SMEs promotes technology-oriented competition among SMEs in contrast to general competitive procurement, which decreases sales by keeping SMEs’ sales constant even in times of severe economic crisis, and guarantees more opportunities for start-ups. It is argued that it plays a role in mitigating the impact of economic fluctuations. Second, it is argued that the competition system between SMEs is being used as a means to achieve the policy objectives of maintaining quality through various quality certification systems in the public purchasing market, providing equal opportunities through a fair bidding process, and protecting SMEs. In addition, it is known that SMEs own production facilities above a certain level and produce them directly to participate in the public procurement market, resulting in a great import substitution effect. And some of the problems of the current direct production verification standards are summarized below. First, as high fixed costs form a barrier to entry into the market, some top companies take the lion’s share the public purchasing market. Second, the price competitiveness weakened in the private and overseas markets due to high fixed costs. Third, it is difficult to specialize in the production process and maintain price competitiveness because the effects of division of labor based on the global value chain cannot be utilized. Fourth, there may be a legal dispute due to the issue of equality between items due to the absence of the basic principle of the direct production verification standard. In order to improve the above problems, this study suggested several alternatives. First, it is to strengthen global competitiveness and create a sound corporate ecosystem through cooperation between companies and revitalization of division of labor. To this end, cooperation between companies should be encouraged by expanding the collaboration regulations applied to the supplementary rules to all items. And in case of emergency, even if production capacity is insufficient, a system should be established so that production capacity can be expanded through cooperation. Second, parts and outsourcing production supplied by domestic SMEs should be recognized as direct production, enhancing the expertise of the production process, and strengthening the linkage of the value chain to reinforce global price competitiveness.

Cooligomerization of γ-butyrolactone with (meth)acrylates catalyzed by N-heterocyclic carbene: Low possibility of hybrid copolymerization

Copolymerization between lactones and vinyl monomers has significant implications for the synthesis of new polymeric materials; however, a highly reactive cyclic monomer, e.g., ε-caprolactone (CL), leads to a copolymeric product but with a complex structure remaining to be elucidated. Herein, we present cooligomerizations of γ-butyrolactone (γBL), a low-polymerizable cyclic monomer, with (meth)acrylates catalyzed by an N-heterocyclic carbene (NHC) under conditions in which no reaction occurs in the absence of either comonomer. Several experimental studies indicate that the product is not a hybrid cooligomer with an ester linkage in the main chain but a graft cooligomer. The reaction mechanism involves the generation of the γBL enolate by the NHC to initiate oligomerizations of γBL and (meth)acrylates followed by the transesterification of oligo (γBL) with an ester unit of (meth)acrylates. These results prompted us to investigate the previously reported structure of copolymer of CL and methyl methacrylate obtained by a phosphazene base catalyst. The hydrolysis experiment revealed that the copolymeric product turned out not to be a hybrid random copolymer.

The Six Lessons of Mises

From the perspective of the market as a process, the market only exists to the extent that exchanges take place. So, what is better in times of social isolation: intervene to ensure that the market works or let the market freeze freely? Moreover, to what extent is it possible to intervene in the market in times of pandemic, preserving the principles of economic freedom? Based on the principles of cooperation and economic calculation proposed by Mises, the objective of this paper is to analyze the possibilities of public policy in a situation of social isolation. Among the main public policy devised in this time of the pandemic, the following measures have provided the continuity of the market process: credit, tax deferrals, and emergency assistance or paycheck protection program. The concern with the preservation of the economic calculation extends to all supply chain linkages, including final customers, for to companies continue to do their economic calculation.

Learning from crisis: repurposing to address grand challenges

ABSTRACT We highlight that institutions may encourage or discourage organizations to engage in the repurposing of technologies and value chain linkages for attaining financial goals and responding to social needs and challenges. Based on evidence from several examples of repurposing and collective action during the recent COVID-19 health crisis, we try to learn and infer, how institutions can create an environment that fosters repurposing beyond crisis situations. Our evidence, accordant to Chris Freeman's argument on the success of nations to catch up and maintain technological and trade competitiveness, suggest that multiple institutional factors may influence a country's ability to design and implement solutions through technological repurposing. We discuss the implications of this result and future research directions.

Suppression of human T cell activation by derivatives of glycerol monolaurate

Glycerol monolaurate (GML), a naturally occurring monoglyceride, is widely used commercially for its antimicrobial properties. Interestingly, several studies have shown that GML not only has antimicrobial properties but is also an anti-inflammatory agent. GML inhibits peripheral blood mononuclear cell proliferation and inhibits T cell receptor (TCR)-induced signaling events. In this study, we perform an extensive structure activity relationship analysis to investigate the structural components of GML necessary for its suppression of human T cell activation. Human T cells were treated with analogs of GML, differing in acyl chain length, head group, linkage of acyl chain, and number of laurate groups. Treated cells were then tested for changes in membrane dynamics, LAT clustering, calcium signaling, and cytokine production. We found that an acyl chain with 12–14 carbons, a polar head group, an ester linkage, and a single laurate group at any position are all necessary for GML to inhibit protein clustering, calcium signaling, and cytokine production. Removing the glycerol head group or replacing the ester linkage with a nitrogen prevented derivative-mediated inhibition of protein cluster formation and calcium signaling, while still inhibiting TCR-induced cytokine production. These findings expand our current understanding of the mechanisms of action of GML and the of GML needed to function as a novel immunosuppressant.

Women empowerment, supply chain linkages and FDI: Evidence from Bangladesh

This paper studies foreign direct investment spillovers on the gender-related labour market practice of domestic firms, based on a unique firm-to-firm data set of Bangladesh’s textiles and garment sectors. The paper looks at the female employment of domestic firms that are directly and indirectly related to foreign- owned firms through supply chain linkages. These domestic firms are either the local suppliers or customers of foreign-owned firms, or they share local suppliers and customers with foreign-owned firms. The estimates show that domestic firms related to foreign-owned firms have significantly more female administrative workers, but not necessarily more female non-administrative workers, owing to the former participating in more firm-to-firm interactions.

The contagion and competitive effects across national borders: Evidence from the 2016 Kumamoto earthquakes

It is unclear how a natural disaster such as earthquake affects disaster-stricken firms' industry peers located in other countries. While those industry peers might benefit from the disaster due to the competitive advantage gained over the disaster-stricken firms (positive competitive effect), they might also suffer from the disaster due to their linkages to the disaster-stricken firms (negative contagion effect). Based on a natural experiment in which a series of earthquakes struck Kumamoto, Japan's Silicon Island, in April 2016, we find that the earthquakes have a negative impact on the stock returns of the semiconductor manufacturers located in China, suggesting that the contagion effect overweighs the competitive effect. Moreover, the negative impact is more pronounced for firms with supply chain connections with Japanese firms. However, we also find a positive impact among Chinese firms with high inventory turnover and customer concentration. Overall, our research reveals the dynamic effects of a natural disaster across national borders, urging firms to pay attention to the negative contagion effect through supply chain linkages and the positive competitive effect resulting from better operational efficiency.

A review of lignin hydrogen peroxide oxidation chemistry with emphasis on aromatic aldehydes and acids

Abstract This review discusses the main factors that govern the oxidation processes of lignins into aromatic aldehydes and acids using hydrogen peroxide. Aromatic aldehydes and acids are produced in the oxidative degradation of lignin whereas mono and dicarboxylic acids are the main products. The stability of hydrogen peroxide under the reaction conditions is an important factor that needs to be addressed for selectively improving the yield of aromatic aldehydes. Hydrogen peroxide in the presence of heavy metal ions readily decomposes, leading to minor degradation of lignin. This degradation results in quinones which are highly reactive towards peroxide. Under these reaction conditions, the pH of the reaction medium defines the reaction mechanism and the product distribution. Under acidic conditions, hydrogen peroxide reacts electrophilically with electron rich aromatic and olefinic structures at comparatively higher temperatures. In contrast, under alkaline conditions it reacts nucleophilically with electron deficient carbonyl and conjugated carbonyl structures in lignin. The reaction pattern in the oxidation of lignin usually involves cleavage of the aromatic ring, the aliphatic side chain or other linkages which will be discussed in this review.

Characterizing gangliosides in six sea cucumber species by HILIC–ESI-MS/MS

An HILIC-ESI-MS/MS method was established to analyze ganglioside (GLS) in sea cucumbers. In total, 17 GLS subclasses were detected in six sea cucumber species. The basic sea cucumber GLSs (SC-GLSs) were elucidated as NeuGc2-6Glc1-1Cer (SC-GM4). The polymerization degree of the sialic acid (Sia) of SC-GLSs can be up to 4, and the linkage among Sias was mostly determined to be 2–8 or 2–11. Neu5Gc, sulfated and fucosylated NeuGc prevalently existed in SC-GLSs. Moreover, a new SC-GLSs structure with phosphoinositidyled Sia was first observed in Bohadschia marmorata. For the first time, we demonstrated that the content of SC-GD4, which is the dominant GLS in sea cucumbers, was 27–67%. Minor GLSs characterized as SC-GT2(Neu5GcMe) and SC-GQ2(Neu5GcMe) were also discovered. Additionally, SC-GD4 and SC-GD4(1S) could significantly promote the differentiation of PC12 cells with structure-selectivity (p < 0.05). Our results provide insights into SC-GLSs to elucidate their Sia substituent and core saccharide chain linkage.

We Are All in the Same Boat

Are assets in a landlocked country subject to sea-level rise risk? In this paper, we study the cross-border spillovers of physical climate risks through international trade and supply chain linkages. As we base our findings on historical data between 1970 and 2018, we observe that globalization increased the similarity of countries’ global climate risk exposures. Exposures to foreign climatic disasters in major trade partner countries (both upstream and downstream) lower the home-country stock market valuation for the aggregate market and for the tradable sectors. We also find that exposures to foreign long-term climate change risks reduce the asset price valuations of the tradable sectors at home. Findings in this paper suggest that climate adaptation efforts in a country can have positive externalities on other countries’ macrofinancial performance and stability through international trade.

Effects of Substituting Polyisoprenyl Carbanions for Ethoxyl Groups of Bis-[3-(triethoxysilyl)propyl] Tetrasulfide on the Properties of Carbon Black and Silica-Reinforced NR/SSBR.

The coupling agent TESPT (bis-[3-(triethoxysilyl)propyl] tetrasulfide) was modified by substituting polyisoprenyl (PI) carbanions for the ethoxyl groups on silicon for increasing the interaction of rubber with its fillers. The modification was carried out by the reaction of TESPT with polyisoprenyllithium, which had been previously prepared by anionic polymerization of isoprene using butyllithium. The success of the substitution was confirmed by Fourier-transform infrared spectroscopy, and the molecular weight of the modified TESPT (PI-TESPT) was determined from gel permeation chromatography measurements. The effects of tethered PI, as well as of its chain length, on the mechanical and dynamic properties of rubber compounds were examined using a universal testing machine and dynamic mechanical analysis (DMA). In rubber sample preparation, the amount of PI3-TESPT (PI of 2900 g/mol) used in rubber compounding is equal to that of the reference sample with TESPT (STESPT). For SPI-TESPT samples, the amounts of PI6-TESPT (PI of 5500 g/mol) and PI14-TESPT (PI of 13,700 g/mol) used were calculated as molar ethoxyl groups which are nearly equivalent to those of PI3-TESPT. At the same wt % (parts per hundred, phr) of elemental sulfur in rubber compounds, despite the order of cross-linking density being STESPT (sample prepared with TESPT) > SPI3-TESPT > SPI6-TESPT > SPI14-TESPT, the exhibited tensile strength is of the order of SPI3-TESPT > SPI6-TESPT > STESPT ≈ SPI14-TESPT. The better mechanical properties of SPI3-TESPT, as opposed to those of STESPT, could be attributed to the extra reinforcement from the PI–rubber chain linkage and better silica dispersion, as suggested by the mixing torque and Payne effect (ΔG′) measurements. While the dynamic properties of SPI3-TESPT are inferior to those of STESPT, these properties can be improved by adding more elemental sulfur to increase the cross-linking density.

Transition-Metal-Free Reductive Cross-Coupling Employing Metabisulfite as a Connector: General Construction of Alkyl–Alkyl Sulfones

Transition-Metal-Free Reductive Cross-Coupling Employing Metabisulfite as a Connector: General Construction of Alkyl–Alkyl Sulfones