Labor-intensive Strategies Research Articles

Elucidation of Sequence–Function Relationships for an Improved Biobutanol In Vivo Biosensor in E. coli

Transcription factor (TF)–promoter pairs have been repurposed from native hosts to provide tools to measure intracellular biochemical production titer and dynamically control gene expression. Most often, native TF–promoter systems require rigorous screening to obtain desirable characteristics optimized for biotechnological applications. High-throughput techniques may provide a rational and less labor-intensive strategy to engineer user-defined TF–promoter pairs using fluorescence-activated cell sorting and deep sequencing methods (sort-seq). Based on the designed promoter library’s distribution characteristics, we elucidate sequence–function interactions between the TF and DNA. In this work, we use the sort-seq method to study the sequence–function relationship of a σ54-dependent, butanol-responsive TF–promoter pair, BmoR-PBMO derived from Thauera butanivorans, at the nucleotide level to improve biosensor characteristics, specifically an improved dynamic range. Activities of promoters from a mutagenized PBMO library were sorted based on gfp expression and subsequently deep sequenced to correlate site-specific sequences with changes in dynamic range. We identified site-specific mutations that increase the sensor output. Double mutant and a single mutant, CA(129,130)TC and G(205)A, in PBMO promoter increased dynamic ranges of 4-fold and 1.65-fold compared with the native system, respectively. In addition, sort-seq identified essential sites required for the proper function of the σ54-dependent promoter biosensor in the context of the host. This work can enable high-throughput screening methods for strain development.

Isolation of Plant Root Nuclei for Single Cell RNA Sequencing.

The characterization of the transcriptional similarities and differences existing between plant cells and cell types is important to better understand the biology of each cell composing the plant, to reveal new molecular mechanisms controlling gene activity, and to ultimately implement meaningful strategies to enhance plant cell biology. To gain a deeper understanding of the regulation of plant gene activity, the individual transcriptome of each plant cell needs to be established. Until recently, single cell approaches were mostly limited to bulk transcriptomic studies on selected cell types. Accessing specific cell types required the development of labor-intensive strategies. Recently, single cell sequencing strategies were successfully applied on isolated Arabidopsis thaliana root protoplasts. However, this strategy relies on the successful isolation of viable protoplasts upon the optimization of the enzymatic cocktails required to digest the cell wall and on the compatibility of fragile plant protoplasts with the use of microfluidic systems to generate single cell transcriptomic libraries. To overcome these difficulties, we present a simple and fast alternative strategy: the isolation and use of plant nuclei to access meaningful transcriptomic information from plant cells. This protocol was specifically developed to enable the use of the plant nuclei with 10× Genomics' Chromium technology partitions technology. Briefly, the plant nuclei are released from the root by chopping into a nuclei isolation buffer before purification by filtration then nuclei sorting. Upon sorting, the nuclei are resuspended in a low divalent ion buffer compatible with the Chromium technology in order to create single nuclei ribonucleic acid-sequencing libraries (sNucRNA-seq). © 2020 Wiley Periodicals LLC. Basic Protocol 1: Arabidopsis seed sterilization and planting Basic Protocol 2: Nuclei isolation from Arabidopsis roots Basic Protocol 3: Fluorescent-activated nuclei sorting (FANS) purification Support Protocol: Estimation of nuclei density using Countess II automated cell counter Alternate Protocol 1: Proper growth conditions for Medicago truncatula and Sorghum bicolor Alternate Protocol 2: Estimation of nuclei density using sNucRNA-seq technology.

Elevated expression of diosgenin-related genes and stimulation of the defense system in Trigonella foenum-graecum (Fenugreek) by cold plasma treatment

Atmospheric pressure plasma jets (APPJs) have been extensively studied for improving plant quality and yield. The effect of different working voltages (3500 V, 4000 V) as well as different exposure times (0.5, 1, 2 and 5 min) was evaluated using dielectric barrier discharge (DBD) plasma jet to determine the best combinations of treatment. The results revealed that there was a significant difference in all tested traits except for chlorophyll b and carotenoid content. The observed increasing activities of catalase (24%), glutathione peroxidase (53%), ascorbate peroxidase (86%) in comparison to control group, suggested that cold plasma treatment has a positive effect on the enhancement of Fenugreek defense system. The results also demonstrated that the total chlorophyll (88%) and protein (49%) content were significantly elevated. Further, the expression of Sterol side chain reductase, Squalene synthase, Squalene epoxidase, Cycloartenol synthase, and Sterol methyltransferase grew by 5.26, 3.42, 1.9, 4.19, and 3-fold, respectively, compared with the control group. This indicates cold plasma treatment as a promising approach to enhance the accumulation of diosgenin in Fenugreek. With respect to this fact that the classical breeding approach is a time-consuming and labor-intensive strategy, cold plasma could be an effective approach to improve plant traits.

Structural change, institutions and the dynamics of labor productivity in Europe

The objective of this paper is to explain the reasons behind the dynamics of labor productivity (LP) growth during a process of institutional and structural change. We show - by means of a theoretical discussion and an empirical analysis, conducted on a sample of 25 European countries for the period 1995–2016 - that four main channels contribute to explaining the evolution of LP. First, the speed of investment, which incorporates innovation and favors an increase of LP growth; second, the speed of Research and Development (R&D), which allows for the creation of new ideas and shows the “dynamism of a society”, having positive effects on LP; third, the deregulation of labor markets and the increase of temporary employment, both of which encourage labor-intensive strategies by firms, with low value-added and low productivity gains; fourth, the direction of structural change, which can take place toward services industries affected by “Baumol’s disease”.

The International Competitive Relationships of Three Leading Countries in the Global Shipbuilding Industry

South Korea, China, and Japan are three dominant countries in the global shipbuilding industry, and the competition between them has become more complex over time. The International Maritime Organization environmental regulations and the wave of Industry 4.0 have made the global shipbuilding industry more technology intensive than before. However, after the financial crisis of 2008, China’s labor-intensive strategy outperformed the technology-intensive competitive strategy adopted by Japan and South Korea, and China was ranked first with the largest market share. This study sets out to explore whether China’s labor-intensive strategy will remain superior to the technology-intensive one of Japan and South Korea. Specifically, we investigate how competitive relationships between the three countries changed after the 2008 global financial crisis. We also forecast how many ships each country will complete in through 2026. To analyze this dynamic competitive system, we use the three-dimensional Lotka-Volterra model, drawing on annual data reporting the number of ships built. The findings suggest that China has gained a competitive advantage over Japan since the 2008 global financial crisis, while South Korea has maintained a mutualistic relationship with both Japan and China. Our forecast suggests that China may lose its competitive advantage in the near future, if China does not embrace a more technology-intensive approach.

Navigating Limited and Uncertain Access to Subsidized Housing After Prison

An emerging literature has documented the challenges that formerly incarcerated individuals face in securing stable housing. Given the increasingly unaffordable rental market, rental subsidies represent an important and understudied source of stable housing for this population. The existing literature has described substantial discretion and a varied policy landscape that determine former prisoners’ access to housing subsidies, or subsidized housing spaces that are leased to members of their social and family networks. Less is known about how former prisoners themselves interpret and navigate this limited and uncertain access to subsidized housing. Drawing on data from repeated qualitative interviews with 44 former prisoners, we describe the creative and often labor-intensive strategies that participants employed to navigate discretion and better position themselves for subsidized housing that was in high demand, but also largely out of reach. Our findings also illustrate the potential costs associated with these strategies for both participants and members of their social and family networks.

The new industrial revolution and industrial upgrading in China: achievements and challenges

One recent development in the area of manufacturing is the New Industrial Revolution (NIR). This paper examines the contours shaping the NIR, and analyses the challenges facing China in its pursuit to achieve technological parity with advanced nations. China’s economic rise is strongly associated with its ascending the technology ladder. The country is now the world’s workshop. As the labour-intensive strategy based on cheap labour has run up against its limits, policy makers have devised plans that focus on industrial upgrading, promote indigenous innovations and establish national brands. This way China would avoid the middle-income trap and eventually become an innovative powerhouse.

Isolation of a Hypomorphic skn-1 Allele That Does Not Require a Balancer for Maintenance.

In Caenorhabditis elegans, the transcription factor SKN-1 has emerged as a central coordinator of stress responses and longevity, increasing the need for genetic tools to study its regulation and function. However, current loss-of-function alleles cause fully penetrant maternal effect embryonic lethality, and must be maintained with genetic balancers that require careful monitoring and labor intensive strategies to obtain large populations. In this study, we identified a strong, but viable skn-1 hypomorphic allele skn-1(zj15) from a genetic screen for suppressors of wdr-23, a direct regulator of the transcription factor. skn-1(zj15) is a point mutation in an intron that causes mis-splicing of a fraction of mRNA, and strongly reduces wildtype mRNA levels of the two long skn-1a/c variants. The skn-1(zj15) allele reduces detoxification gene expression and stress resistance to levels comparable to skn-1 RNAi, but, unlike RNAi, it is not restricted from some tissues. We also show that skn-1(zj15) is epistatic to canonical upstream regulators, demonstrating its utility for genetic analysis of skn-1 function and regulation in cases where large numbers of worms are needed, a balancer is problematic, diet is varied, or RNAi cannot be used.

Management of a sandbag accident in an MRI unit

Our aim is to report the cause and management of a ferromagnetic sandbag accident that occurred when an unconscious patient was sent for brain MRI. A 2-kg sandbag had been placed in the vicinity of his right groin to aid hemostasis after a femoral venous puncture for thrombocytopenia. His clothing and blanket had not been examined thoroughly before he was moved to the scanner and the sandbag went unnoticed. Its attraction to the scanner and adherence to the scanner rim resulted in a minor abrasion and bruise on the patient’s face. We decided to manually remove some of the pellets from the sandbag after cutting the vinyl bag at one corner with a nonferromagnetic screwdriver. Piece-meal removal of about two-thirds of the pellets facilitated removal of the remaining pellets and the sandbag as a whole. The word “sandbag” is misleading and led to a lack of communication between the clinical team and the MRI staff and failure by the MRI staff to recognize a sandbag as a ferromagnetic object. Careful manual removal of small amounts of pellets can be used to avoid more time- and labor-intensive strategies to deal with a sandbag accident (e.g., magnet quench or ramp-down). Installation of a ferromagnetic material detector to screen patients before entering the scanner room is recommended.

Archaeological data as evidence of sustainable development: cases from the Gulf Coast of Mexico

Traditional knowledge as a source of sustainable development is a research topic that generally falls in the realm of ethnology and social anthropology. Archaeology, on the other hand, can provide the longue durée perspective on past and sometimes lost traditions that may be significant as modern sustainable strategies. This paper presents archaeological cases of long-standing traditional knowledge in agriculture and construction in the humid tropical lowlands of the Mexican Gulf Coast, which were lost about ad 1000 through episodes of cultural conflict. The first case concerns the agricultural use of wetlands for the intensive production of commercial and subsistence crops (cotton and maize). The second case is monumental earthen architecture, including pyramids and palaces, apparently achieved by using petroleum derivatives as an earth stabilizer. Besides evidencing sustainable practices, archaeology also provides the economical and socio-political context in which such labor-intensive strategies evolved and thrived for centuries. This context analysis allows cost–benefit concerns to be approached, if the reintroduction of such alternative technologies were contemplated in a modern market-oriented world.

De novo isolation of antibodies with pH-dependent binding properties

pH-dependent antibodies are engineered to release their target at a slightly acidic pH, a property making them suitable for clinical as well as biotechnological applications. Such antibodies were previously obtained by histidine scanning of pre-existing antibodies, a labor-intensive strategy resulting in antibodies that displayed residual binding to their target at pH 6.0. We report here the de novo isolation of pH-dependent antibodies selected by phage display from libraries enriched in histidines. Strongly pH-dependent clones with various affinity profiles against CXCL10 were isolated by this method. Our best candidate has nanomolar affinity for CXCL10 at pH 7.2, but no residual binding was detected at pH 6.0. We therefore propose that this new process is an efficient strategy to generate pH-dependent antibodies.

AI-Based Software Defect Predictors: Applications and Benefits in a Case Study

Software defect prediction aims to reduce software testing efforts by guiding testers through the defect-prone sections of software systems. Defect predictors are widely used in organizations to predict defects in order to save time and effort as an alternative to other techniques such as manual code reviews. The application of a defect prediction model in a real-life setting is difficult because it requires software metrics and defect data from past projects to predict the defect-proneness of new projects. It is, on the other hand, very practical because it is easy to apply, can detect defects using less time and reduces the testing effort. We have built a learning-based defect prediction model for a telecommunication company during a period of one year. In this study, we have briefly explained our model, presented its pay-off and described how we have implemented the model in the company. Furthermore, we have compared the performance of our model with that of another testing strategy applied in a pilot project that implemented a new process called Team Software Process (TSP). Our results show that defect predictors can be used as supportive tools during a new process implementation, predict 75% of code defects, and decrease the testing time compared with 25% of the code defects detected through more labor-intensive strategies such as code reviews and formal checklists.

Retrospective Analysis of Monkeypox Infection

Serologic cross-reactivity between orthopoxviruses is a substantial barrier to laboratory diagnosis of specific orthopoxvirus infections and epidemiologic characterization of disease outbreaks. Historically, time-consuming and labor-intensive strategies such as cross-adsorbed neutralization assays, immunofluorescence assays, and hemagglutination-inhibition assays have been used to identify orthopoxvirus infections. We used cross-adsorption to develop a simple and quantitative postadsorption ELISA for distinguishing between monkeypox and vaccinia infections. Despite the difficulty of diagnosing clinically inapparent monkeypox in previously vaccinated persons, this technique exhibited 100% sensitivity and 100% specificity for identifying clinically overt monkeypox infection irrespective of vaccination history. We also describe a Western blot technique in which up to 3 diagnostic bands may be used to distinguish between vaccinia and monkeypox infection. The techniques described provide independent diagnostic tests suitable for retrospective analysis of monkeypox outbreaks.

Design of protease-resistant myelin basic protein-derived peptides by cleavage site directed amino acid substitutions

Multiple Sclerosis (MS) is considered to be a T cell-mediated autoimmune disease. An attractive strategy to prevent activation of autoaggressive T cells in MS, is the use of altered peptide ligands (APL), which bind to major histocompatibility complex class II (MHC II) molecules. To be of clinical use, APL must be capable of resisting hostile environments including the proteolytic machinery of antigen presenting cells (APC). The current design of APL relies on cost- and labour-intensive strategies. To overcome these major drawbacks, we used a deductive approach which involved modifying proteolytic cleavage sites in APL. Cleavage site-directed amino acid substitution of the autoantigen myelin basic protein (MBP) resulted in lysosomal protease-resistant, high-affinity binding peptides. In addition, these peptides mitigated T cell activation in a similar fashion as conventional APL. The strategy outlined allows the development of protease-resistant APL and provides a universal design strategy to improve peptide-based immunotherapeutics.

Selection strategies for the establishment of recombinant Chinese hamster ovary cell line with dihydrofolate reductase-mediated gene amplification

To evaluate the efficacy of selection strategies for recombinant Chinese hamster ovary (rCHO) clones undergone with dihydrofolate reductase-mediated gene amplification, rCHO cell lines producing a chimeric antibody were established using two strategies, one based on individual clones and the other based on cell pools. In a selection based on individual clones, cell cloning by limiting dilution method was performed twice, once after a round of selection of parental cell clones and once after obtaining high-producer clones. Thirty parental clones selected from 300 parental clones were cultivated independently throughout the gene amplification procedure. Using this labor-intensive strategy, it took approximately 17 weeks to obtain high-producing clones such as CS11-8 and CS18-3 clones. A selection based on cell pools, in which cell cloning was performed once at the final selection stage, required less effort and time to amplify large numbers of individual parental clones within the pool. However, high-producing clones were lost during the amplification procedure. The antibody expression level of high-producing clones such as PS7-2 and PS7-32 chosen on the basis of cell pools was less than one third of that of CS11-8 and CS18-3 clones. Taken together, a selection strategy based on individual clones is favored for establishment of high-producing rCHO clones because it is more efficient to perform cell cloning at the initial selection stage of parental cell clones.

Dynamic and Responsive Firm Strategy

Since the opening of China in 1980, Hong Kong manufacturing industries collaborated with China manufacturing industries to maintain a low-cost labor intensive strategy. The strategy seems to be sufficient in maintaining the global competitive advantage of Hong Kong for the past two decades. However, with the rapid organizational learning of the Chinese partner and the reluctance of the Hong Kong partner to upgrade technology, Hong Kong manufacturing industries are facing the risk of potential loss of competitive advantages. This article attempts to review this dynamic evolution of HK/China collaborations and suggest some future actions for Hong Kong manufacturing industries to maintain their competitiveness. At the same time, the article also provides some ideas for global investors to rethink their future firm strategies in China.

RACE AND CLASS BIAS IN QUALITATIVE RESEARCH ON WOMEN

Exploratory studies employing volunteer subjects are especially vulnerable to race and class bias. This article illustrates how inattention to race and class as critical dimensions in women's lives can produce biased research samples and lead to false conclusions. It analyzes the race and class background of 200 women who volunteered to participate in an in-depth study of Black and White professional, managerial, and administrative women. Despite a multiplicity of methods used to solicit subjects, White women raised in middle-class families who worked in male-dominated occupations were the most likely to volunteer, and White women were more than twice as likely to respond to media solicitations or letters. To recruit most Black subjects and address their concerns about participation required more labor-intensive strategies involving personal contact. The article discusses reasons for differential volunteering and ways to integrate race and class into qualitative research on women.

The Structure of Indonesian Manufacturing Industry: An Input-Output Approach∗

The paper examines the structure of Indonesia's manufacturing sector, using data from the 1980 input-output tables., and supporting data from various industrial surveys and national accounts. An input-output analysis of sectoral linkages and factor demand (labour, proxies for skill and capital, imports) is used to derive implications for growth and employment of two contrasting industrial development strategies — a labour-intensive strategy and a more capital-intensive strategy fostering basic industries. It is argued that a labour-intensive, resource-based, and export-oriented strategy combined with selective import substitution is most likely to achieve the stated development goals of the Indonesian government. ∗ Part of the work on this study was financed under the Netherlands technical assistance programme and by the Bureau Data and Analysis (BDA) of the Ministry of Industry of Indonesia The authors gratefully acknowledge the permission of BDA and BPS to use provincial 1980 input-output data. Special ...

Educational Reform and Manpower Policy in China, 1955-1958

This paper will demonstrate that the radical educational reforms of the Great Leap Forward were initiated because of changing conceptions of manpower needs, and economic development plans and priorities. As the Chinese leadership became increasingly sensitive to the limited applicability of the capital-intensive strategy of development of the First Five Year Plan, they began to scale down the training of a limited number of very highly educated technical personnel. The new, more labor-intensive strategy required a much larger number of less well-educated, but more highly motivated and politically conscious workers. These changes in manpower needs eventually led to the radical educational reforms that emerged during the Great Leap Forward. We will trace the development of Chinese manpowertraining policy in the crucial years, 1955-1958. During those years the Chinese government experimented with a variety of programs and policies that would enable them to overcome the limitations of the Soviet model of development which they had adopted in their First Five Year Plan. Since manpower training policy is central to any developmental scheme, the