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Optimization of a Low-Cost Corona Dielectric-Barrier Discharge Plasma Wastewater Treatment System through Central Composite Design/Response Surface Methodology with Mechanistic and Efficiency Analysis
Get PDFWater pollution, which is intensified by the release of hard-to-degrade pollutants, poses severe threats to ecosystems, human health, and economic development. The existing advanced oxidation processes often involve high operational costs and can potentially result in secondary pollution, highlighting the necessity for innovative and more sustainable solutions. To address these challenges, our study introduces a cost-effective and eco-friendly corona dielectric-barrier discharge for wastewater treatment. Using the central composite design/response surface methodology, a high decolorization rate of 98% of methylene blue (MB) was achieved within 10 min by optimizing parameters such as pH and voltage. Furthermore, the mechanisms underlying the generation of reactive oxygen species through this device were discussed in detail and the degradation pathways of MB were elucidated. Moreover, this device is very energy-efficient, exhibiting a low energy density and electrical energy per order of 0.15 watt/mL and 5.79 kWh/m3/order, respectively. In conclusion, the plasma discharger developed in this study provides a cost-effective and environmentally sustainable solution for dye wastewater treatment. This research contributes significantly to the advancement of sustainable dye wastewater management practices, offering an innovative method that meets both environmental and economic objectives
Reactive Dye Wash-Off Processing of Cotton Fabrics Using Polymer Dye Transfer Inhibitors for Sustainable Dyeing
Get PDFCotton fiber consumption is higher than any other natural fiber due to its superior mechanical and physical properties. In the conventional reactive dyeing process, the dye undergoes hydrolysis due to hydrogen bonding and weak Van der Waals forces, yielding poor washing color fastness. Additionally, the post-dyeing wash-off process consumes significant amounts of water, energy, and time in order to remove the unreacted and hydrolyzed dye. Therefore, reactive dyes are predominantly utilized to color cotton fabrics as the covalent bond formed between dye and fiber results in excellent washing fastness for a wide range of colors, and improved ease of use. To support more efficient, economical, and sustainable reactive dyeing, polymers can be used as effective dye transfer inhibitors (DTIs) in the reactive wash-off process. In this study, poly(vinylpyrrolidone) (PVP) homopolymer and poly(vinylpyrrolidone)-co-poly(vinylimidazole) (PVP-co-PVI) were synthesized at different molecular weights. These polymers were then employed as DTIs to evaluate their performance during the wash-off process for dyed cotton fabrics treated with three reactive dyes (Reactive Red 195, Reactive Blue 221, and Reactive Yellow 145). It is noteworthy to mention that the alternative wash-off procedure involved only three stages, in contrast to the series of washing steps necessary in the conventional method. Evaluation of the DTIs was focused on parameters such as color strength, washing fastness, chemical oxygen demand (COD), as well as energy, water, and time consumption. The findings revealed that while the polymer DTIs generated minor differences in dyed fabric colors in comparison to conventional dyeing, they significantly improved washing fastness. The polymer DTIs studied display excellent potential to provide a much more sustainable dyeing process by saving 90% energy, 40% water, and 50% time versus conventional wash-off processing. The wastewater COD values from the polymer-assisted reactive dye wash-off process were higher for all reactive dyes tested than those from conventional processing. While the higher COD values are attributed to the lower water volumes, this finding highlights the need for further studies. In summary, PVP polymers successfully served as DTIs in the reactive dyeing washing-off process, providing massive water-energy-time efficiency improvements and, subsequently, a more sustainable process for cotton fabric dyeing
Inducing Experimental Bacterial Chondronecrosis with Osteomyelitis Lameness in Broiler Chickens Using Aerosol Transmission Model
Get PDFLameness disease attributed to bacterial chondronecrosis with osteomyelitis in broilers affects production, animal welfare, and food safety in the poultry industry. The disease is characterized by necrotic degeneration of the rapidly growing femora and tibiae due to bacterial translocation from the respiratory or gastrointestinal tracts into the blood circulation, eventually colonizing the growth plate of the long bones. To investigate the etiology, pathogenesis, and intervention measures for BCO, developing an experimental model that reliably induces BCO lameness is of the utmost importance. In the past, we have employed a wire -flooring model and a litter -flooring model administered with a bacterial challenge to investigate strategies for mitigating BCO. However, multiple issues on labor-intensive barn setup and cleanout efforts for the wire -flooring system and concern of direct pathogenic exposure to the broilers for the litter -flooring models rendered these research models less effective. Thus, we investigated a new approach to induce experimental BCO lameness using an aerosol transmission model employing a group of birds reared on wire -flooring pens as a BCO infection source, and the disease is further disseminated through the airborne transmission to other birds reared on litter flooring in the same housing environment. The effectiveness of the aerosol transmission model in inducing BCO lameness was concluded from 4 independent experiments. The cumulative lameness generated from the BCO source group on the wire floors versus negative control treatments on the litter floors from Experiments 1, 2, 3, and 4 were 84% vs. 69.33%, P = 0.09; 54.55% vs. 60%, P = 0.56; 78% vs. 73.50%, P = 0.64; 81% vs. 74.50%, P = 0.11. Overall, the cumulative lameness generated from the wire floors was successfully transmitted to the birds on litter floors without significant statistical differences (P \u3e 0.05). The effectiveness of the aerosol transmission model for experimentally triggering BCO lameness provides a reliable system for evaluating practical intervention strategies for BCO lameness in broilers
Effect of Heat Stress on the Hypothalamic Expression Profile of Water Homeostasis-associated Genes in Low- and High-water Efficient Chicken Lines
Get PDFWith climate change, selection for water efficiency and heat resilience are vitally important. We undertook this study to determine the effect of chronic cyclic heat stress (HS) on the hypothalamic expression profile of water homeostasis-associated markers in high (HWE)- and low (LWE)-water efficient chicken lines. HS significantly elevated core body temperatures of both lines. However, the amplitude was higher by 0.5–1°C in HWE compared to their LWE counterparts. HWE line drank significantly less water than LWE during both thermoneutral (TN) and HS conditions, and HS increased water intake in both lines with pronounced magnitude in LWE birds. HWE had better feed conversion ratio (FCR), water conversion ratio (WCR), and water to feed intake ratio. At the molecular level, the overall hypothalamic expression of aquaporins (AQP8 and AQP12), arginine vasopressin (AVP) and its related receptor AVP2R, angiotensinogen (AGT), angiotensin II receptor type 1 (AT1), and calbindin 2 (CALB2) were significantly lower; however, CALB1 mRNA and AQP2 protein levels were higher in HWE compared to LWE line. Compared to TN conditions, HS exposure significantly increased mRNA abundances of AQPs (8, 12), AVPR1a, natriuretic peptide A (NPPA), angiotensin I-converting enzyme (ACE), CALB1 and 2, and transient receptor potential cation channel subfamily V member 1 and 4 (TRPV1 and TRPV4) as well as the protein levels of AQP2, however it decreased that of AQP4 gene expression. A significant line by environment interaction was observed in several hypothalamic genes. Heat stress significantly upregulated AQP2 and SCT at mRNA levels and AQP1 and AQP3 at both mRNA and protein levels, but it downregulated that of AQP4 protein only in LWE birds. In HWE broilers, however, HS upregulated the hypothalamic expression of renin (REN) and AVPR1b genes and AQP5 proteins, but it downregulated that of AQP3 protein. The hypothalamic expression of AQP (5, 7, 10, and 11) genes was increased by HS in both chicken lines. In summary, this is the first report showing improvement of growth performances in HWE birds. The hypothalamic expression of several genes was affected in a line- and/or environment-dependent manner, revealing potential molecular signatures for water efficiency and/or heat tolerance in chickens
Lithicone-Protected Lithium Metal Anodes for Lithium Metal Batteries with Nickel-Rich Cathode Materials
Get PDFThe high energy density advantage of lithium (Li) metal batteries (LMBs) makes them increasingly desirable; however, problems such as strong reactivity and dendrite growth of Li metal anode limit their practical uses. In this work, a novel Li-containing glycerol (LiGL) or lithicone protection layer on a 50 μm thick Li metal anode is employed for improving the performance of LMBs. This LiGL layer was accurately deposited via a molecular layer deposition (MLD) process at 150°C, using lithium tert-butoxide and glycerol as precursors. The as-formed LiGL coating layer is highly tunable in its thickness by simply adjusting MLD cycles and shows a good stability and outstanding ionic transport properties. The LiGL layer is found to effectively mitigate side reactions and enhance cycling stability in both symmetric cells and full cells. Specifically, the LMBs with LiGL@Li anode of 400 MLD cycles and LiNi0.6Mn0.2Co0.2O2 cathode enable a capacity retention of ≈87%, much higher than ≈35% of the cells with bare Li after 200 cycles at a charge/discharge current density of 2.1 mA cm−2. This work paves a feasible way for practical LMBs with improved capacity and stability through applying an innovative protection layer on Li metal anodes
Multimodal Boiling Dataset with Synchronized Acoustic, Optical, and Thermal Measurements Under Steady-State and Transient Heat Loads
Get PDFBoiling is a high-performance heat dissipation process that is central to electronics cooling and power generation. However, there exists a practical limit of boiling heat transfer known as the critical heat flux (CHF), beyond which significant performance degradation is observed. Understanding the physical mechanism that triggers CHF is essential to meet the increasing cooling demands driven by power densification and device miniaturization. However, the high dimensionality, stochasticity, and dynamicity of the boiling process have led to strong challenges in the experimental characterization and modeling of boiling CHF. As such, high-frame rate, high-resolution, multi-physics boiling datasets are critical to advancing the fundamental understanding of boiling heat transfer. To this end, this paper presents a multimodal boiling dataset consisting of synchronized thermal, acoustic, and optical signals collected from five different heater surfaces under two distinct heat load conditions. With its high sampling frequency, diverse signal types, large data volume, and detailed recorded information, this dataset provides valuable data blood for the field of thermal crisis monitoring. This dataset will not only promote fundamental research on bubble dynamics during boiling but also support the implementation of advanced monitoring technologies in industrial applications such as power electronics, motors, data centers, and power plants
Corporate Crisis Management: A Contemporary Best Practices Template
Get PDFThis paper seeks to re-envision the crisis management framework used by organizations in their day-to-day activities. In the modern world, with exponential technological advancements, the social media age, and the 24/7 news cycle, crises have worsened in severity. Despite this, most literature on the subject is more than a decade old.
Incorporating past literature, this thesis demonstrates that society is in an “era of crises,” then defines and discusses the types and origins of these crises. It compares the topics of issues and crisis management before commentating on corporate and academic literature and ultimately previous 3-stage models for crisis management.
Finally, it outlines a modern and modified framework for crisis management, drawing from other 3-stage models and the bevy of crises faced since the turn of the century. By dividing the crisis cycle into pre-crisis, crisis onset & duration, and post-crisis, it gives organizations a simple, yet effective guide to navigating these events before generating its own model that highlights each stage of the crisis, points to tangible steps that should be taken at those times and displays the inevitability of the crisis feedback loop that necessitates this continuous improvement
Development of Tissue-Engineered Model of Fibrotic Scarring after Spinal Cord Injury to Study Astrocyte Activation and Neurite Outgrowth In Vitro
No full textTraumatic spinal cord injuries (SCI) are debilitating injuries affecting twenty-seven million people worldwide and cause functional impairments. Despite decades of research and medical advancements, current treatment options for SCI remain limited, in part due to the complex pathophysiology of spinal cord lesions including cellular transformation and extracellular matrix (ECM) remodeling. Recent studies have increased focus on fibrotic scarring after SCI, and yet much remains unclear about the impact of fibrotic scarring on SCI lesion progression. Here, using collagen and decellularized spinal cord-based composite hydrogels, a three-dimensional (3D) cell culture model mimicking the fibrous core of spinal cord lesions was implemented to investigate its influence on the surrounding astrocytes. To mimic the fibrotic milieu, collagen fibril thickness was tuned using previously established temperature-controlled casting methods. In our platforms, astrocytes in fibro-mimetic hydrogels exhibited increased levels of activation markers such as glial fibrillary acidic protein and N-cadherin. Furthermore, astrocytes in fibro-mimetic hydrogels deposited more fibronectin and laminin, further hinting that astrocytes may also contribute to fibrotic scarring. These markers were decreased when Rho-ROCK and integrin β1 were inhibited via pharmacological inhibitors. Mechanistic analysis of Yes-associated protein reveals that blocking integrin β1 prevents mechanosensing of astrocytes, contributing to altered phenotypes in variable culture conditions. In the presence of these inhibitors, astrocytes increased the secretion of brain-derived neurotrophic factor, and a greater degree of dorsal root ganglia neurite infiltration into the underlying hydrogels was observed. Altogether, this study presents a novel tissue-engineered platform to study fibrotic scarring after SCI and may be a useful platform to advance our understanding of SCI lesion aggravation
Deciphering the Interdomain Coupling in a Gram-Negative Bacterial Membrane Insertase
No full textYidC is a membrane protein that plays an important role in inserting newly generated proteins into lipid membranes. The Sec-dependent complex is responsible for inserting proteins into the lipid bilayer in bacteria. YidC facilitates the insertion and folding of membrane proteins, both in conjunction with the Sec complex and independently. Additionally, YidC acts as a chaperone during the folding of proteins. Multiple investigations have conclusively shown that Gram-positive bacterial YidC has Sec-independent insertion mechanisms. Through the use of microsecond-level all-atom molecular dynamics (MD) simulations, we have carried out an in-depth investigation of the YidC protein originating from Gram-negative bacteria. This research sheds light on the significance of multiple domains of the YidC structure at a detailed molecular level by utilizing equilibrium MD simulations. Specifically, multiple models of YidC embedded in the lipid bilayer were constructed to characterize the critical role of the C2 loop and the periplasmic domain (PD) present in Gram-negative YidC, which is absent in its Gram-positive counterpart. Based on our results, the C2 loop plays a role in the overall stabilization of the protein, most notably in the transmembrane (TM) region, and it also has an allosteric influence on the PD region. We have found critical inter- and intradomain interactions that contribute to the stability of the protein and its function. Finally, our study provides a hypothetical Sec-independent insertion mechanism for Gram-negative bacterial YidC
Supply Chain Management Internship – J.B. Hunt Transportation Services, Inc.
Get PDFTransportation is all over the world as it is a part of our daily lives. It connects the supply chain from sourcing raw goods from suppliers to delivering finished products to stores. Whether by road, rail, air, or sea, transportation bridges the geographical gaps that separate markets and economies, ensuring the timely delivery of essential goods, and fostering economic growth and development. Since beginning of my fall semester of 2023, I had the opportunity to intern at J.B. Hunt Transport Services Inc. as an Intermodal Appointment Intern. My experience has deepened my appreciation for the complexities of the industry and has provided me with valuable skills and knowledge that I continue to apply as I grow both professionally and personally