Recovery Procedure Research Articles

Ligament rotation-dominated creep in stochastic bicontinuous nanoporous metallic glass

Bicontinuous nanoporous metallic glasses (BNPMGs) are promising candidates in functional applications such as energy storage, sensors, and fuel cells. The time-dependent deformation strongly affects their long-term in-service performance. This study investigates the tensile creep behavior and its underlying deformation mechanisms of Cu50Zr50 BNPMGs through molecular dynamics simulations. The creep-recovery fatigue behavior is revealed. Our results manifest that both the transient and steady creep strengths increase with the solid fraction. The transient strength is larger for smaller ligament sizes, but the steady creep strength has very mild sensitivity to the ligament size. The generalized Kelvin model, consisting of two Kelvin units and one Maxwell unit connected in series, can accurately predict the creep and recovery curves. The rotation of individual ligaments, rather than atomic diffusion, is the dominant creep mechanism. During creep, the shear transformation zones are mainly developed on the ligament surface, and the strain in the ligament core is relatively smaller. The creep stress exponent has no definite relation with the creep mechanism and decreases with the increasing solid fraction. With the increase in the creep-recovery cycle number, the creep rate decreases, and the recovery procedure makes a milder impact on the creep response.

Internal Audit Operational Efficiency and Performance of Public Institutions in Rwanda: The Case of Ngoma District

This study aimed to investigate the impact of internal audit operational efficiency on the performance of public institutions in Rwanda, using a case study of Ngoma District. The study aimed to identify the main internal control activities, assess the role of internal audit operations in identifying and assessing risks, establish the effects of internal audit operations on ensuring compliance with laws, regulations, and internal policies, analyze the contributions of internal audit operations in detecting and deterring fraudulent activities, and find out the impact of an effective audit system on operational efficiency. The target population consisted of 120 staff working at the Ngoma District head office in Kigali, with 92 being a sample. Primary data was collected through structured questionnaires and secondary data from Ngoma District reports and online resources. The statistical analysis revealed several strong and highly significant correlations between internal audit operationalization processes and the performance of public institutions. There is a substantial positive correlation between the internal audit processes of File Verification, approval, and Authorization and the institution's ability to detect and assess risks. The study also demonstrates a significant correlation between computer system control measures in the internal audit process and an institution's ability to adhere to legal requirements, regulations, and internal policies. A strong and statistically significant correlation is found between the implementation of backup and file recovery procedures and the prevention of fraudulent activities, emphasizing the importance of data integrity and security in maintaining trustworthiness. Finally, the research reveals a robust and statistically significant association between staff monitoring and the operational efficiency of public institutions, underlining the critical role of accountability and supervision in streamlining processes and resource allocation. These findings emphasize the significance of comprehensive internal audit practices and controls in enhancing the performance, governance, and effectiveness of public institutions in Ngoma district. Keywords: Internal Audit, Operational Efficiency, Public Institutions, Rwanda

Determination of the optimal period for computations control in complexes of automated control systems programs

The purpose of the study is to determine the optimal period for monitoring calculations in complex software complexes of automated control systems. To achieve this goal, it is necessary to solve such problems as the analysis of periodic control systems, which boils down to determining the performance costs of computing systems for control, as well as ensuring a minimum of these costs. Theoretical foundations and descriptions of the process of evaluating the effectiveness of the automated control systems functioning are given. A rationale for the method of determining the optimal period for monitoring calculations in software complexes of the automated control systems is provided in the paper. An analytical study of control systems is carried out. The difference between the considered problem setting and the existing ones lies in the fact that the accuracy of error detection by the periodic control system is taken into account, while it is taken into account that for real control systems the probability of error detection is quite high. Thus, the results of studying the operational periodic control systems have shown that the main parameters that affect the optimal period of control are the mean time between failures. The dependence of the optimal control period on the probability of recovery is shown for different values of the duration of recovery by a reliable method. As the probability decreases, the optimal control period also decreases, which is associated with the need to spend a large proportion of the time on restoration using a reliable method; the corresponding increase in average unit costs can be compensated by an increase in the frequency of control procedures, i. e. a decrease in the control period. The dependence of the minimum average unit cost of control and the optimal period of its implementation on the average time between the errors appearance is given. With constant durations of control and recovery procedures and constant error detection probability, the optimal control period decreases, and the minimum average unit cost increases somewhat with a decrease in the average time between failures. This can be explained as follows: the more often an error can occur, the more often you need to control in order to reduce the losses due to working with the error.

Deceased Organ Donor Management and Organ Distribution From Organ Procurement Organization-Based Recovery Facilities Versus Acute-Care Hospitals.

Introduction: Organ recovery facilities address the logistical challenges of hospital-based deceased organ donor management. While more organs are transplanted from donors in facilities, differences in donor management and donation processes are not fully characterized. Research Question: Does deceased donor management and organ transport distance differ between organ procurement organization (OPO)-based recovery facilities versus hospitals? Design: Retrospective analysis of Organ Procurement and Transplant Network data, including adults after brain death in 10 procurement regions (April 2017-June 2021). The primary outcomes were ischemic times of transplanted hearts, kidneys, livers, and lungs. Secondary outcomes included transport distances (between the facility or hospital and the transplant program) for each transplanted organ. Results: Among 5010 deceased donors, 51.7% underwent recovery in an OPO-based recovery facility. After adjustment for recipient and system factors, mean differences in ischemic times of any transplanted organ were not significantly different between donors in facilities and hospitals. Transplanted hearts recovered from donors in facilities were transported further than hearts from hospital donors (median 255 mi [IQR 27, 475] versus 174 [IQR 42, 365], P = .002); transport distances for livers and kidneys were significantly shorter (P < .001 for both). Conclusion: Organ recovery procedures performed in OPO-based recovery facilities were not associated with differences in ischemic times in transplanted organs from organs recovered in hospitals, but differences in organ transport distances exist. Further work is needed to determine whether other observed differences in donor management and organ distribution meaningfully impact donation and transplantation outcomes.

Efficacy of Electromyographic Biofeedback in the Recovery of the Vastus Lateralis after Knee Injury: A Single-Group Case Study

Electromyographic biofeedback (EMG-BF) is a technique that can contribute to the improvement of muscle tone and control in the rehabilitation process after injury. The aim of this research was to determine the effectiveness of EMG-BF in increasing the electromyographic activity of the vastus lateralis after knee injury. The sample consisted of four individuals who had undergone surgery or rehabilitation to resolve either a partial meniscal tear or a patellar tendon strain. The intervention consisted of a program of ten sessions of EMG-BF work. Twelve trials were performed in each session, in which participants were instructed to target the muscle tension produced by the vastus lateralis of the uninjured hemilateral limb. Of the twelve trials in each session, the first three and the last three were performed without feedback, and the intermediate six with feedback. The recording of muscle activity was performed using CY-351/2 Mioback equipment, which allowed the amplitude of the electromyographic signal to be evaluated. The results indicated that the sample analyzed reached greater amplitude during the biofeedback trials, both for the maximum (Z = −13.43, p &lt; 0.001, Cohen’s d = 0.64, 95% CI (0.27, 1.01)) and mean (Z = −7.26, p &lt; 0.001, Cohen’s d = 0.24, 95% CI (−0.12, 0.60)) values. The amplitude also increased throughout the ten sessions, both for the maximum (Z = −3.06, p &lt; 0.01, Cohen’s d = 1.37, 95% CI (0.29, 2.45)) and mean (Z = −3.06, p &lt; 0.01, Cohen’s d = 1.20, 95% CI (0.34, 2.08)) values. Thus, the results highlight the efficacy of this technique in improving muscle activity, suggesting that it is a useful therapeutic procedure in injury recovery.

Investigation of active voltage support control approach of DC distribution networks based on virtual inertia coordination

AbstractDC distribution networks (DCDNs) possess the advantages of high power efficiency, low operation loss, and favourable control flexibility, and are regarded as an essential form of future power distribution systems. In order to increase the voltage transient performance of DCDNs against disturbances, this paper proposes a methodology for realising the active voltage support control of DCDNs based on virtual inertia coordination. Firstly, the impact of the inertia of DCDNs towards the transient voltage change is analysed, and the active voltage support mechanism considering the variable droop inertia control and virtual DC motor inertia (VDCMI) control is explored. Then, a time sequence coordination strategy based on the voltage grading of DCDNs is developed, and an adaptive inertia coefficient is designed to achieve the inertia adjustment in terms of the voltage sag and recovery processes. Using MATLAB/Simulink, a detailed model of the double‐terminal DCDNs is created to check the efficacy of the proposed approach. Different voltage disturbance scenarios are imitated, and the comparative simulations demonstrate that the proposed approach can fully utilise the inertia potential of the DCDNs to suppress the voltage sag and smooth the voltage recovery procedure. The proposed method's validity and feasibility can be well validated.The cover image is based on the Original Article Investigation of active voltage support control approach of DC distribution networks based on virtual inertia coordination by Lei Chen et al., https://doi.org/10.1049/esi2.12123.

E-Waste Management: An Analysis under the Perspective of Conflicts and Shared Responsibility

Background: The Brazilian National Solid Waste Policy establishes the shared responsibility of all actors involved in e-waste generation and management; however, some conflicts of interest need interventions and approaches for preventing them. Objective: This paper proposes using a graph model for conflict resolution (GMCR) decision support system to simulate the analysis and resolution of realistic e-waste management conflicts. Method: A systematic literature review focused on e-waste management, shared responsibility and conflict management was conducted, and a graph model for conflict resolution (GMCR) decision support system was applied to generate a framework to address this context. Results: The need for commitment agreements promoted by government institutions in partnerships with companies involved in the process is essential since the principle of shared responsibility requires educational actions, favoring efficiency in the reverse logistics recovery procedures for e-waste. Understanding the interconnected causes of conflicts and their facets is crucial for effective resolution and prevention, aiding comprehension, focused interventions, and evidence-based decision-making for transformative change amidst conflicting stakeholder objectives in the case of WEEE management. These results can be helpful for academics and practitioners working in this area.

Experimental results of electromagnetic analysis on smartcard

Abstract— Electromagnetic analysis attack is a form of side channel attack that can be used to reveal secret information of a cryptographic device by examination of electromagnetic radiations. The effectiveness of EMA has a large dependences on the quality of the electromagnetic radiation measured by the measuring system and how the EM traces are simulated during the key recovery procedures. In this paper, we propose the practical procedure for electromagnetic analysis attack methods and the experimental results of EMA on smartcard that implemented AES algorithm, including assessing the influence of measuring system, radiation leakage model on effectiveness of attacks.

How is music listening purpose related to stress recovery? - two preliminary studies in men and women.

Studies have suggested that listening to music can reduce psychological and biological responses to a stressor. However, it is unclear whether music has the same effect on stress recovery. According to field studies, people commonly use music in daily life for the specific purpose of relaxation. We explored whether individuals who generally use music for relaxation purposes show improved recovery from an acute stressor. In two independent studies, twenty-seven healthy female participants (Mage = 24.07) (Study 1) and twenty-one healthy male participants (Mage = 23.52) (Study 2) were separated into two groups based on their frequency of using music for relaxation purposes (low vs. high). All participants underwent a lab-based psychosocial stress test. Subjective stress levels were measured using visual analogue scales. Salivary cortisol and salivary alpha-amylase were measured to assess endocrine and autonomic stress responses, respectively. Subjective stress levels and saliva samples were measured nine times throughout the stress induction and recovery procedure. Chronic stress levels were assessed using the Perceived Stress Scale and the Screening Scale of Chronic Stress. No significant differences were observed in subjective stress levels, salivary alpha-amylase activity, or cortisol concentration between the two groups in either of the two studies. Further analyses revealed that among male participants, increased use of music for relaxation purposes was related to more chronic stress levels (t (10.46) = 2.45, p = 0.03, r = 0.60), whereas female participants exhibited a trend in the opposite direction (t (13.94) = -1.92, p = 0.07, r = 0.46). Contrary to our expectations, the results indicate that habitual music listening for relaxation purposes is not associated with improved recovery from a stressor. However, due to the small sample size, future exploration is necessary to enhance the statistical power of the results of the study.

Do Cooperative credit unions reduce or increase poverty in Cameroon?

AbstractPurposeThis study looks at whether credit unions, a type of microfinance, increase or decrease poverty in Cameroon from 2004 Q1 to 2021 Q4.Method/designThe fully modified ordinary least square, dynamic ordinary least square, and conical co‐integration is applied.FindingsThe findings reveal a long‐term association between credit union measures and poverty levels. The results indicate that the number of credit unions, the number of commercial bank branches, and credit to the private sector negatively relate to poverty levels. This implies that as the number of credit unions increases, the poverty level increases as the credit unions tend to exploit the poor population. Outstanding deposits positively impact poverty levels, which imply that members’ deposits alleviate poverty.Research implicationsThe government should refurbish the existing programs to enhance credit unions' activities to focus more on banking the poor population especially in remote areas. The credit unions should increase deposit mobilization from the public to empower individuals and businesses. The government should regulate the number of credit unions being created to limit exploitation. The government should intervene to ensure that credit unions’ policy regarding lending, interest rates, and loan recovery procedures are mutually agreed upon by the parties.Originality/noveltyLimited studies used secondary data focusing on credit unions. The studies give conflicting results: Some studies reveal that microfinance banks positively affect poverty reduction. Some indicate negative effects of microfinance on poverty reduction. Others show that microfinance institutions do not significantly influence poverty reduction. Different opinions exist among depositors and borrowers of credit unions concerning poverty alleviation. Some credit union members hold that credit unions increase poverty, while others argue that credit unions alleviate poverty.

Impact of cornea recovery training and certification on ophthalmology residents

BackgroundIn Asian countries, such as Taiwan, social taboos regarding organ and tissue donation decreases the prevalence of organ and tissue transplants. This also applies to cornea recovery, which is a skill that requires precision and practice to perform well. In Taiwan, to ensure the maintenance of high-quality corneas, a comprehensive training program and certified examination has been implemented. This study aims to investigate the impact of these programs and examinations on cornea recovery. MethodsResearchers evaluated the efficiency of the training and certified examination process by comparing the corneoscleral rim width, Descemet's membrane folds, endothelial layer stress lines, and endothelial cell density performed by ophthalmology residents in 2018 and 2019. ResultsAfter training and certification, the Descemet's membrane folds rate decreased from 14.3 % to 2.0 % and endothelial layer stress lines rate decreased from 22.5 % to 5.0 %. The endothelial cell density of donor grafts significantly improved from 2681.9 cells/mm2 to 2869.7 cells/mm2 (p < 0.001). ConclusionsThis study used objective data to evaluate cornea recovery quality after training and certification. The training and certified examination significantly improved the surgical skills of ophthalmology residents and could be applied in other tissue or organ recovery procedures to maintain and improve quality.

Cloud Metering and Monitoring

For Service Oriented Infrastructures (SOI) and Cloud services, monitoring and metering are crucial tasks. For the proper execution of cloud applications &amp; the monitoring of SLA compliance, the data gathered through monitoring is required. The motivations for and challenges in monitoring and metering cloud systems are discussed. The methods for monitoring the network and execution environment on virtualized infrastructures will be discussed together with the monitoring tools that are now available on various commercial and research platforms. Every distributed computing system has a basic feature that includes monitoring chores. Every service should be watched over in order to evaluate its effectiveness and enable remedial measures in the event of failure. A functional snapshot of the system's behaviour along the time axis is what monitoring data reflects. Such information is essential for pinpointing the source of issues or for fine-tuning various system components. For example, failure detection and recovery procedures require a monitoring component to determine whether to restart a specific server or subsystem based on the data gathered by the monitoring system.

Biosurfactant: an emerging tool for the petroleum industries.

The petroleum sector is essential to supplying the world's energy demand, but it also involves numerous environmental problems, such as soil pollution and oil spills. The review explores biosurfactants' potential as a new tool for the petroleum sector. Comparing biosurfactants to their chemical equivalents reveals several advantages. They are ecologically sustainable solutions since they are renewable, nontoxic, and biodegradable. Biosurfactants are used in a variety of ways in the petroleum sector. They can improve the mobilization and extraction of trapped hydrocarbons during oil recovery procedures. By encouraging the dispersion and solubilization of hydrocarbons, biosurfactants also assist in the cleanup of oil spills and polluted locations by accelerating their breakdown by local microorganisms. The review gives insights into alternative methods for the petroleum industry that are more viable and cost-effective.

A novel application of recovered stresses in stress intensity factors extraction methods for the generalized/extended finite element method

SummaryAn efficient improvement to compute Stress Intensity Factors (SIFs) in two‐dimensional fracture mechanics problems solved by Generalized/eXtended Finite Element Method and Stable Generalized Finite Element Method is proposed. A stress field obtained by a recovery procedure based on a locally weighted projection of the approximate stresses, is used in the formulation of two energy‐based SIFs extraction methods: the Contour Integral Method (CIM) and the Interaction Integral strategy. The accuracy and the path independence feature of the proposed approach are investigated in three numerical examples, considering crack opening modes I and II, different crack orientations and the presence of holes. The results demonstrate that the recovered stresses significantly improve the accuracy of the CIM and ensure a notable decrease in SIFs variation for different integration paths. On the other hand, an equivalent impact is not observed for the Interaction Integral strategy.

A Novel Procedure for Comprehensive Recovery of Zinc Fluoride, Manganese Fluorides, Manganese Dioxide, and Carbon Powder from the Electrode Powder of Spent Alkaline Batteries

A Novel Procedure for Comprehensive Recovery of Zinc Fluoride, Manganese Fluorides, Manganese Dioxide, and Carbon Powder from the Electrode Powder of Spent Alkaline Batteries

Perioperative Care Innovations: Optimizing Recovery and Reducing Complications in General Surgery

Significant progress has been made in perioperative care for general surgery with the goal of minimising postoperative complications and improving patient outcomes. This thorough analysis examines developments in the preoperative, intraoperative, and postoperative domains of the perioperative continuum. This article explores the most recent innovations influencing the profession, with a focus on patient-centered tactics, technology improvements, and interdisciplinary approaches.&#x0D; Within the context of preoperative optimisation, therapies aimed at correcting dietary deficiencies, individualised exercise programmes, and psychological preparedness are critical to improving surgical patient readiness. Improved surgical methods, such as robotics and minimally invasive surgery, revolutionise surgical accuracy while reducing trauma and facilitating a quicker recovery.&#x0D; Innovations in postoperative care, such improved recovery procedures and remote monitoring devices, speed up recovery and lower complications. Pain treatment and infection control advances in pharmacology have a major positive impact on patient comfort and lower morbidity.&#x0D; This study emphasises the value of customised treatment plans, collaborative decision-making, and specialised communication while embracing patient-centered methods. It highlights how important it is for patients to be involved in their treatment, how to promote their own autonomy, and how to improve compliance with postoperative instructions.&#x0D; This study seeks to highlight the combined influence of these breakthroughs on changing general surgery perioperative care paradigms through an examination of these advances. The perioperative setting is driven by the combination of innovative tactics, cooperation across varied healthcare specialties, and technology breakthroughs with the ultimate goal of optimising recovery and minimising problems.

Temperature Dependence of Water Crossover in Proton Exchange Membrane Water Electrolysis

The importance of hydrogen production by proton exchange membrane water electrolysis (PEMWE) in the energy sector makes it worthwhile to understand the system behaviour in failure cases and possible recovery procedures. In particular, insufficient feed water supply to the anode can be caused by inhomogeneous distribution in the stack, pump failure or erroneous operation strategy. For the PEMWE, a distinct turnover point has been reported if feed water supply is reduced in isothermal conditions.[1] Further reduction of the water supply results in higher ohmic resistance due to gradual membrane dehydration and increased mass transport losses.[2] Here, we will use the term “water starvation” to describe this event. The drainage of water from the anode can be explained by oxygen evolution reaction (OER), humidification of oxygen gas and water crossover to the cathode. The last one was measured for well hydrated membranes at atmospheric pressure [3] or below typical operating temperatures [4].In the first part of this work, we present the water crossover in a PEMWE on single cell level to understand their dependence on the operating parameters such as temperature and pressure. Media were supplied and conditioned to a 5 cm2 single cell by using an in-house test bench and a potentiostate with booster. The electrochemical measurements were performed with a commercially available catalyst coated perfluorosulfonic acid membranes (loading of 0.3 mg/cm2 geo Pt/C on cathode and 1 mg/ cm2 geo Ir-Oxide on anode). The anode was kept at atmospheric pressure, whereas the cathode pressure was varied from atmospheric to 400 kPaabs at various current densities and cell temperatures of 40 – 80 °C. To determine the water crossover under several operating conditions, the water vapour was condensed to liquid phase in a heat exchanger and measured by a gravimetric method.Furthermore, the measured water crossover is used to force a water starvation in the second part of this work. After cell assembly, a conditioning procedure was performed until steady cell performance was achieved. Cell performance was evaluated using polarization curve, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and water crossover. The last two are of particular interest, because they provide information about membrane humidification. The Tafel slope and mass transport overvoltage were evaluated from the polarization curves and high frequency resistance (HFR). Water starvation experiments were then carried out at a constant cell voltage by reducing the feed water supply, resulting in a dramatic decay of the current density. The analysis of Tafel slope and EIS data reveals an increase of ohmic and mass transport resistances. Furthermore, the HFR measurements were correlated with water crossover as a function of membrane hydration. We observed that the specific water crossover per current density decreases as a consequence of membrane dehydration. After this step, feed water supply was increased to an unrestricting level for membrane rehydration and performance recovery. For this recovery procedure, different operation modes were employed by varying the current densities. At constant current density, membrane hydration is influenced by the ionic current from the cathode to the anode via proton drag. EIS and water crossover measurements allow us to determine the influence of operation on the dynamics of the membrane rehydration process. Together with the polarization curves, cyclic voltammetry and HFR data, reversible and irreversible degradation processes caused by the water starvation can be identified.Altogether, we present a deeper understanding of water crossover for a wide operating parameter range and provide a guideline for recovery of the performance for PEMWE.[1] Christoph Immerz et al 2020 Meet. Abstr. MA2020-02 2456[2] C. Immerz, B. Bensmann, P. Trinke, M. Suermann, R. Hanke-Rauschenbach, J. Electrochem. Soc. 2018, 165, F1292-F1299.[3] K. Onda, T. Murakami, T. Hikosaka, M. Kobayashi, R. Notu, K. Ito, J. Electrochem. Soc. 2002, 149, A1069.[4] P. Medina, M. Santarelli, International Journal of Hydrogen Energy 2010, 35, 5173.

Performance Losses and Recovery from Cation Contaminants in PEM Water Electrolysis

Water contaminants are extremely common cause of failure for polymer electrolyte membrane (PEM) electrolyzers, potentially accounting for >90% of electrolyzer failures in the field. [1] Water contaminants also commonly impact PEM electrolysis devices in a research setting, confusing measurements of cell performance and durability if they are not recognized and properly addressed. Despite this, relatively little published literature has systematically investigated contaminants in PEM electrolysis cells specifically. Better understanding of contaminant impacts may lead to improved strategies to mitigate or recover performance losses as well as improve the consistency and rigor of electrolysis research.Here we will present an investigation of the performance impacts of cation contaminants and their recoverability. This investigation focuses on cation contaminants that are abundant in tap/ground water, which may enter the cell through a failure of the water processing subsystem, and transition metals that may leach out of system components. We will report performance impacts for a representative selection of cations as a function of water concentration and accumulated contaminant dose, with impedance spectroscopy used to understand the origin of performance losses. We will also present multiple diagnostic signatures to help identify presence of contaminants in PEM electrolysis cells. Finally, we will address the recovery of cells with different contaminants and the prospects for improved recovery procedures.[1] Capuano, Chris “Manufacturing Challenges, Opportunities, and Successes for PEM Electrolysis at Scale”, 3rd International Conference on Electrolysis, Golden, CO, 2022.

A DNA assembly toolkit to unlock the CRISPR/Cas9 potential for metabolic engineering

CRISPR/Cas9-based technologies are revolutionising the way we engineer microbial cells. One of the key advantages of CRISPR in strain design is that it enables chromosomal integration of marker-free DNA, eliminating laborious and often inefficient marker recovery procedures. Despite the benefits, assembling CRISPR/Cas9 editing systems is still not a straightforward process, which may prevent its use and applications. In this work, we have identified some of the main limitations of current Cas9 toolkits and designed improvements with the goal of making CRISPR technologies easier to access and implement. These include 1) A system to quickly switch between marker-free and marker-based integration constructs using both a Cre-expressing and standard Escherichia coli strains, 2) the ability to redirect multigene integration cassettes into alternative genomic loci via Golden Gate-based exchange of homology arms, 3) a rapid, simple in-vivo method to assembly guide RNA sequences via recombineering between Cas9-helper plasmids and single oligonucleotides. We combine these methodologies with well-established technologies into a comprehensive toolkit for efficient metabolic engineering using CRISPR/Cas9. As a proof of concept, we developed the YaliCraft toolkit for Yarrowia lipolytica, which is composed of a basic set of 147 plasmids and 7 modules with different purposes. We used the toolkit to generate and characterize a library of 137 promoters and to build a de novo strain synthetizing 373.8 mg/L homogentisic acid.

Recent Advances in the Utilization of Tungsten Residue: A Mini Review of China

As a metal of strategic value, tungsten plays an important part in civil and military applications. Currently, China is the biggest tungsten producer all over the world, and the metallic smelting technologies for tungsten are well established. However, the harmless recovery and treatment procedures for tungsten residue remain rather underdeveloped. The treatment of tungsten residue generally includes the recovery of valuable metals (e.g., scandium, tantalum, and niobium) and the solidification of toxic elements (e.g., arsenic, lead, and chromium), which may control the transfer of these elements and metals. If treated improperly, the resource of tungsten residue may be wasted, and potential environmental risks could arise. Therefore, the safe disposition of tungsten residue has become the limit factor and an urgent problem to be solved for the sustainable development of tungsten-related industries. In this regard, we reviewed the industrial background of tungsten and the composition and toxicity characteristics of tungsten residue. In addition, particular attention was paid to the harmless utilization processes and technologies for tungsten residue, which were then systematically compared in terms of the applicable situations as well as their advantages and shortcomings. Finally, the development trend for the harmless utilization of tungsten residue was discussed, and some proposals for further studies were provided.