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The COVID-19 pandemic outbreak deeply impressed supply chains in different aspects. In response to this unexpected situation, supply chain managers have decided to recover and reinforce their supply chains. Considering the expanse of these decisions, project management principle and tools seems inevitable to successfully manage the transformation from before pandemic to post-pandemic supply chains (SCs). In this study, the problem of time–cost tradeoff is extended to time, cost, and risk tradeoff. The risk factor is considered to convey the uncertainty arising from the COVID-19 pandemic situation. Since projects are affected by the level of pandemic expansion and different countries ruled out various quarantine policies (isolation, quarantine, social distancing, and lock-down), the tradeoff problem is influenced accordingly. Therefore, a scenario-based robust optimization model is proposed to deal with time, cost, and risk tradeoff problems to reflect the effects of the global pandemic of COVID-19 on managing projects in supply chains. In addition, various quarantine policies (isolation, quarantine, social distancing, and lock-down) as a prevalent response to the pandemic have been investigated separately. To illustrate the model, a real-world case study in the emerging economy of Iran is examined using the proposed approach. The results indicated that supply chain managers can use the designed model and approach as a tool for a flexible and adaptable decision-making framework dealing with a global pandemic such as COVID-19.

Cotton (Gossypium hirsutum L.) is an important crop in the world and increasing its fiber quality is very cr-ucial for textile industries. Spider silk is the strongest and most elastic fiber ever known in the nature. Cotton is one of the main crops in the world and increasing its fiber quality is very important for textile industries. In this regard, a synt-hetic construct has been designed to offer spider silk quality to cotton fibers by fiber-specific expression of Major am-pullate spidroin1 (MaSp1) gene under control of core sequence of GaRD22-like1 promoter. The synthetic construct was double digested by the EcoRI and NheI and sub-cloned in pCAMBIA1304 binary vector. E.coli DH5α was transformed using new plasmid namely pCSP. Ligation and intact backbone of plasmid was conformed using MaSp1 and hygrom-ycin re-sistance genes specific primers and finally with EcoRI/NheI double digestion. Agrobacterium tumefaciens LBA4404 was transformed with pCSP to transform cotton ovules of Varamin cultivar. The expression of MaSp1 in co-tton ovules and fibers showed that this synthetic sequence had been successfully expressed under control of GaRDL1 core promoter and this construct without codon optimization could be used for cotton transformation and its fiber qual-ity manipulation.

Quinoxaline derivatives have been synthesized in high yields in the presence of cellulose sulfuric acid as an inexpensive, recyclable and biodegradable solid acid catalyst in H2O or EtOH at room temperature.

The oxidation of organic compounds by NaBrO 3 under heteropoly acid catalysis in aqueous acetonitrile at room temperature has been studied. Primary and secondary aromatic alcohols are converted to aldehydes and ketones, alkyl arenes and sulfides oxidized to corresponding ketones and sulfoxide, respectively. In contrary, thiols undergo oxidative coupling reactions to give disulfides. The reaction was carried out in various solvents or under solvent free conditions. The reaction exhibited better results in terms of the yield and rate in H 2 O/CH 3 CN.

By combining a ceric ammonium nitrate (CAN)–catalyzed aerobic oxidation of α-hydroxy ketones with a subsequent three-component condensation reaction using aldehydes and ammonium acetate, highly substituted imidazole derivatives can be assembled. This reaction is an important approach for the synthesis of highly substituted imidazole derivatives and was carried out in good to excellent yields in ethanol as an environmentally benign solvent.

A new, one-pot, four-component reaction for the synthesis of a novel class of highly substituted 1,4-dihydro-1,8-naphthyridine-3-carboxamide derivatives starting from readily available inputs including aliphatic or aromatic amines, diketene, aromatic aldehydes, and 2-aminopyridines in the presence of a catalytic amount of p-toluenesulfonic acid under mild reaction conditions and in good yields at ambient temperature is described.

A one-pot four-component reaction of an aliphatic or aromatic amine, diketene, an aromatic aldehyde and 1,3-diphenyl-1H-pyrazol-5-amine in the presence of p-toluenesulfonic acid as a catalyst has been developed. In this reaction, a new class of fully substituted pyrazolo[3,4-b]pyridine-5-carboxamide derivatives is produced under mild reaction conditions and in good yields at ambient temperature.

A new, one-pot, four-component reaction for the synthesis of a novel class of highly substituted 1,4-dihydro-1,8-naphthyridine-3-carboxamide derivatives starting from readily available inputs including aliphatic or aromatic amines, diketene, aromatic aldehydes, and 2-aminopyridines in the presence of a catalytic amount of p-toluenesulfonic acid under mild reaction conditions and in good yields at ambient temperature is described.

In this work, 1,2,3,4,5,8-hexahydro-1,3,7-trimethyl-2,4-dioxopyrido[2,3-d]pyrimidine-6-carboxamide derivatives were synthesized in a simple and efficient method from the four-component condensation reaction of diketene, an aliphatic or aromatic amine, an aromatic aldehyde, and 6-amino-1,3-dimethyluracil in the presence of a catalytic amount of p-toluenesulfonic acid under mild conditions at ambient temperature in high yields.

A one-pot four-component reaction of an aliphatic or aromatic amine, diketene, an aromatic aldehyde and 1,3-diphenyl-1H-pyrazol-5-amine in the presence of p-toluenesulfonic acid as a catalyst has been developed. In this reaction, a new class of fully substituted pyrazolo[3,4-b]pyridine-5-carboxamide derivatives is produced under mild reaction conditions and in good yields at ambient temperature.

By combining a ceric ammonium nitrate (CAN)–catalyzed aerobic oxidation of α-hydroxy ketones with a subsequent three-component condensation reaction using aldehydes and ammonium acetate, highly substituted imidazole derivatives can be assembled. This reaction is an important approach for the synthesis of highly substituted imidazole derivatives and was carried out in good to excellent yields in ethanol as an environmentally benign solvent.

In this work, 1,2,3,4,5,8-hexahydro-1,3,7-trimethyl-2,4-dioxopyrido[2,3-d]pyrimidine-6-carboxamide derivatives were synthesized in a simple and efficient method from the four-component condensation reaction of diketene, an aliphatic or aromatic amine, an aromatic aldehyde, and 6-amino-1,3-dimethyluracil in the presence of a catalytic amount of p-toluenesulfonic acid under mild conditions at ambient temperature in high yields.