A Data-Driven Packaging Efficiency Optimization Method for a Low Carbon System in Agri-Products Cold Chain

The of monitoring the Internet of Things (IoT) in the cold chain allows process data, including packaging data, to be more easily accessible. Proper optimization modelling is the core driving force towards the green and low-carbon operation of cold chain logistics, laying the necessary foundation for the development of a data-driven modelling system. Since efficient packaging is necessary for loss control in the cold chain, its final efficiency during circulation is important for realizing continuous loss prevention and efficient supply. Thus, it is urgent to determine how to utilize these continuously acquired data and how to formulate a more accurate packaging efficiency control methodology in the agri-products cold chain. Through continuous monitoring, we examined the feasibility of this topic by focusing on the concept of data-driven evaluation modelling and the dynamic formation mechanism of comprehensive packaging efficiency in cold chain logistics. The packaging efficiency in the table grape cold chain was used as an example to evaluate the comprehensive efficiency evaluation index system and data-driven evaluation framework proposed in this paper. Our results indicate that the established methodology can adapt to the continuity of comprehensive packaging efficiency, also reflecting the comprehensive efficiency evaluation of the packaging for different times and distances. Through the evaluation of our results, the differences and the dynamic processes between different final packaging efficiencies at different moments are effectively displayed. Thus, the continuous improvement of a low-carbon system in cold chain logistics could be realized.

Anti-Counterfeiting and Traceability Mechanism Based on Blockchain

The anti-counterfeiting traceability system based on blockchain technology can ensure the accuracy and consistency of the data stored by each participating node, protect the legitimacy of the data, ensure the product quality, improve the credibility of enterprises, and enhance consumers’ confidence in products. However, due to the low system throughput, high energy consumption and poor data availability, the combination of blockchain and traditional anti-counterfeiting traceability mode has many challenges, such as low efficiency. This paper aims to find an improved consensus mechanism based on contribution proof to improve the mining efficiency of honest miners. And plan to introduce a credit system, give priority to the high credit value of the mining block to package, improve the overall packaging efficiency of the system, to solve the problem of low feedback efficiency of the blockchain anti-counterfeiting system.

Staphylococcal phages and pathogenicity islands drive plasmid evolution

Conjugation has classically been considered the main mechanism driving plasmid transfer in nature. Yet bacteria frequently carry so-called non-transmissible plasmids, raising questions about how these plasmids spread. Interestingly, the size of many mobilisable and non-transmissible plasmids coincides with the average size of phages (~40 kb) or that of a family of pathogenicity islands, the phage-inducible chromosomal islands (PICIs, ~11 kb). Here, we show that phages and PICIs from Staphylococcus aureus can mediate intra- and inter-species plasmid transfer via generalised transduction, potentially contributing to non-transmissible plasmid spread in nature. Further, staphylococcal PICIs enhance plasmid packaging efficiency, and phages and PICIs exert selective pressures on plasmids via the physical capacity of their capsids, explaining the bimodal size distribution observed for non-conjugative plasmids. Our results highlight that transducing agents (phages, PICIs) have important roles in bacterial plasmid evolution and, potentially, in antimicrobial resistance transmission.

Metal-based nanoparticles, sensors, and their multifaceted application in food packaging

Due to the global rise of the human population, one of the top-most challenges for poor and developing nations is to use the food produces safely and sustainably. In this regard, the storage of surplus food (and derived products) without loss of freshness, nutrient stability, shelf life, and their parallel efficient utilization will surely boost the food production sector. One of the best technologies that have emerged within the last twenty years with applications in the packaging of food and industrial materials is the use of green mode-based synthesized nanoparticles (NPs). These NPs are stable, advantageous as well as eco-friendly. Over the several years, numerous publications have confirmed that these NPs exert antibacterial, antioxidant, and antifungal activity against a plethora of pathogens. The storage in metal-based NPs (M-NPs) does not hamper the food properties and packaging efficiency. Additionally, these M-NPs help in the improvement of properties including freshness indicators, mechanical properties, antibacterial and water vapor permeability during food packaging. As a result, the nano-technological application facilitates a simple, alternate, interactive as well as reliable technology. It even provides positive feedback to food industries and packaging markets. Taken together, the current review paper is an attempt to highlight the M-NPs for prominent applications of antimicrobial properties, nanosensors, and food packaging of food items. Additionally, some comparative reports associated with M-NPs mechanism of action, risks, toxicity, and overall future perspectives have also been made.

Improved Genome Packaging Efficiency of AAV Vectors Using Rep Hybrids

Recombinant Adeno-associated viruses (rAAVs) are one of the most commonly used vectors for a variety of gene therapy applications. In the last two decades research focused primarily on the characterization and isolation of new cap genes resulting in hundreds of natural and engineered AAV capsid variants while the rep gene, the other major AAV open reading frame, has been less studied. This is due to the fact that the rep gene from AAV serotype 2 (AAV2) enables the ssDNA packaging of recombinant genomes into most AAV serotype and engineered capsids. However, a major byproduct of all vector productions is empty AAV capsids, lacking the encapsidated vector genome, especially for non-AAV2 vectors. Despite the packaging process being considered the rate-limiting step for rAAV production, none of the rep genes from the other AAV serotypes have been characterized for their packaging efficiency. Thus, in this study AAV2 rep was replaced with the rep gene of a select number of AAV serotypes. However, this led to a lowering of capsid protein expression, relative to the standard AAV2- rep system. In further experiments the 3’end of the AAV2 rep gene was reintroduced to promote increased capsid expression and a series of chimeras between the different AAV Rep proteins were generated and characterized for their vector genome packaging ability. The utilization of these novel Rep hybrids increased the percentage of genome containing (full) capsids ∼2-4-fold for all of the non-AAV2 serotypes tested. Thus, these Rep chimeras could revolutionize rAAV production. Importance A major byproduct of all Adeno-associated virus (AAV) vector production systems are “empty” capsids, void of the desired therapeutic gene, and thus do not provide any curative benefit for the treatment of the targeted disease. In fact, empty capsids can potentially elicit additional immune responses in vivo gene therapies if not removed by additional purification steps. Thus, there is a need to increase the genome packaging efficiency and reduce the number of empty capsids from AAV biologics. The novel Rep hybrids from different AAV serotypes described in this study are capable of reducing the percentage of empty capsids in all tested AAV serotypes and improve overall yields of genome-containing AAV capsids at the same time. They can likely be integrated easily into existing AAV manufacturing protocols to optimize the production of the generated AAV gene therapy products.

New homozygous gpt delta transgenic rat strain improves an efficiency of the in vivo mutagenicity assay

Background Gene mutation assays in transgenic rodents are useful tools to investigate in vivo mutagenicity in a target tissue. Using a lambda EG10 transgene containing reporter genes, gpt delta transgenic mice and rats have been developed to detect point mutations and deletions. The transgene is integrated in the genome and can be rescued through an in vitro packaging reaction. However, the packaging efficiency is lower in gpt delta rats than in mice, because of the transgene in gpt delta rats being heterozygous and in low copy number. To improve the packaging efficiency, we herein describe a newly developed homozygous gpt delta rat strain. Results The new gpt delta rat has a Wistar Hannover background and has been successfully maintained as homozygous for the transgene. The packaging efficiency in the liver was 4 to 8 times higher than that of existing heterozygous F344 gpt delta rats. The frequency of gpt point mutations significantly increased in the liver and bone marrow of N-nitroso-N-ethylurea (ENU)- and benzo[a]pyrene (BaP)-treated rats. Spi− deletion frequencies significantly increased in the liver and bone marrow of BaP-treated rats but not in ENU-treated rats. Whole genome sequencing analysis identified ≥ 30 copies of lambda EG10 transgenes integrated in rat chromosome 1. Conclusions The new homozygous gpt delta rat strain showed a higher packaging efficiency, and could be useful for in vivo gene mutation assays in rats.

Influenza A virus defective viral genomes are inefficiently packaged into virions relative to wild-type genomic RNAs

Deletion-containing viral genomes (DelVGs) are commonly produced during influenza A virus infection and have been implicated in influencing clinical infection outcomes. Despite their ubiquity, the specific molecular mechanisms that govern DelVG formation and their packaging into defective interfering particles (DIPs) remain poorly understood. Here, we utilized next-generation sequencing to analyze DelVGs that form de novo early during infection, prior to packaging. Analysis of these early DelVGs revealed that deletion formation occurs in clearly defined hotspots and is significantly associated with both direct sequence repeats and enrichment of adenosine and uridine bases. By comparing intracellular DelVGs with those packaged into extracellular virions, we discovered that DelVGs face a significant bottleneck during genome packaging relative to wild type genomic RNAs. Surprisingly, packaged DelVGs exhibited no signs of enrichment for specific deletion characteristics suggesting that all DelVGs are equally limited in packaging efficiency. Our data provide the first unbiased, high-resolution portrait of the diversity of DelVGs that are generated by the IAV replication machinery and shed light on the mechanisms that underly DelVG formation.

Improved Genome Packaging Efficiency of AAV Vectors Using Rep Hybrids

Recombinant Adeno-associated viruses (rAAVs) are one of the most commonly used vectors for a variety of gene therapy applications. In the last two decades research focused primarily on the characterization and isolation of new cap genes resulting in hundreds of natural and engineered AAV capsid variants while the rep gene, the other major AAV open reading frame, has been less studied. This is due to the fact that the rep gene from AAV serotype 2 (AAV2) enables the ssDNA packaging of recombinant genomes into most AAV serotype and engineered capsids. However, a major byproduct of all vector productions is empty AAV capsids, lacking the encapsidated vector genome, especially for non-AAV2 vectors. Despite the packaging process being considered the rate-limiting step for rAAV production, none of the rep genes from the other AAV serotypes have been characterized for their packaging efficiency. Thus, in this study AAV2 rep was replaced with the rep gene of a select number of AAV serotypes. However, this led to a lowering of capsid protein expression, relative to the standard AAV2-rep system. In further experiments the 3’end of the AAV2 rep gene was reintroduced to promote increased capsid expression and a series of chimeras between the different AAV Rep proteins were generated and characterized for their vector genome packaging ability. The utilization of these novel Rep hybrids increased the percentage of genome containing (full) capsids ~2-4-fold for all of the non-AAV2 serotypes tested. Thus, these Rep chimeras could revolutionize rAAV production.

Overcoming Immunological Challenges Limiting Capsid-Mediated Gene Therapy With Machine Learning

A key hurdle to making adeno-associated virus (AAV) capsid mediated gene therapy broadly beneficial to all patients is overcoming pre-existing and therapy-induced immune responses to these vectors. Recent advances in high-throughput DNA synthesis, multiplexing and sequencing technologies have accelerated engineering of improved capsid properties such as production yield, packaging efficiency, biodistribution and transduction efficiency. Here we outline how machine learning, advances in viral immunology, and high-throughput measurements can enable engineering of a new generation of de-immunized capsids beyond the antigenic landscape of natural AAVs, towards expanding the therapeutic reach of gene therapy.

Investigation on material combination technique to enhance the anti-wrinkle and anti-vibration characteristics of the planar membrane reflector

In recent trends, membrane structure has increased its applications in space missions due to its significant advantages, such as light in weight, higher folding and packaging efficiency, ease of deployment, and low on-Board volume requirement. The wrinkling and low natural frequency of vibration are the major problems with the membrane structure. This research presents a novel methodology of Kapton-Kevlar material combination for a planar membrane reflector to enhance anti-vibration and anti-wrinkling capabilities of the membrane structure. The comparative study is made for the wrinkle area, RMS error, and natural frequency of vibration with the employed approach. This study provides new insights into a material combination technique to increase performance characteristics of the space-borne membrane reflectors. The outcome of the wrinkling analysis is compared and found to be consistent with the method available in the literature. From the simulation results, it is observed that wrinkles are reduced, and the natural frequency of vibration is also increased significantly with the proposed method.