Regeneration Time Research Articles

From two segments and beyond: Investigating the onset of regeneration in Syllis malaquini.

Annelids feature a diverse range of regenerative abilities, but complete whole-body regeneration is less common, particularly in the context of the head and anterior body regeneration. This study provides a detailed morphological description of Syllis malaquini regenerative abilities. By replicating previous experiments and performing diverse surgical procedures, we explored the capacity of this species for whole-body regeneration. We detailed the precise timing of regeneration of particular structures such as the eyes, proventricle, pharyngeal tooth, nuchal organs, and body pigmentation after amputation. Our high-resolution scanning electron microscopy and confocal laser-scanning microscopy images provide details of the blastema region, revealing that while anal opening remains in connection to the exterior environment, oral opening is formed "de novo" during blastema differentiation. Additionally, we performed amputations to isolate fragments consisting of one, two, and three segments from the intestinal trunk region. We found that S. malaquini requires at least two to three segments to successfully regenerate the whole body. In addition, we verified a variable capacity to regenerate depending upon the gut region, with structures of the foregut greatly impairing some steps of the regenerative process. Our work notably addresses the gap in knowledge concerning gut formation and its impact on regenerative capabilities. Ongoing research is crucial to unravel the role of gut tissue specificity and plasticity during regeneration in annelids, and particularly in syllids.

Nanoporous Metatitanic acid on γ-Al2O3 aerogel for higher CO2 adsorption capacity and lower energy consumption

Carbon dioxide capture has become an important issue in reducing atmospheric heat these days. In this study, adsorption of carbon dioxide by aerogel Gamma Alumina-Metatitanic Acid has been investigated and optimized. Morphological and structural analyses such as BET, FESEM, FT-IR, and XRD have also been conducted. In addition, Response surface methodology has been applied in order to achieve the optimal conditions, using a five-level Central composite design. The highest amount of adsorption, 12.874 (mmol/g), was recorded at a temperature of 20 (°C), pressure of 7 (bar), and 25 (%wt) of Metatitanic Acid. This was approximately 11.46% and 4.84% higher than those of mesoporous MgO and 4Azeolite, respectively. Regeneration of the adsorbent was also studied at different temperatures and process durations. Metatitanic acid, as a catalyst, reduces the temperature and regeneration time of the adsorbent by creating active sites and surface hydroxyl groups. It also lowers the required activation energy and enhances the thermal conductivity of the composite material. The optimal result was achieved at a temperature of 100 (°C) and a duration of 30 (min). Finally, isothermal and thermodynamic experiments were conducted to establish the most accurate predictive model and conditions, including Enthalpy, Entropy, and Gibbs free energy. The results indicate that the Freundlich model aligned well with the laboratory findings. Additionally, the negative values of Enthalpy, Entropy, and Gibbs free energy suggested that the adsorption process was physical, exothermic, and spontaneous.

Comparative performance assessment of different halide composites in sorption cooling system: A dynamic approach

The adsorption technique presents a promising approach for cooling, heat storage, and gas storage. This study focuses on the viability of adsorption in cooling applications, specifically utilizing various halide salts in conjunction with thermal energy, highlighting its potential as an energy-efficient solution for modern energy demands. A dynamic numerical model is developed and used to study the performance of transverse finned reactor-based adsorption cooling system (ACS) with different halide composite salts. The simulations are carried out at different supply pressures ranging from 3.55 bar to 7.28 bar corresponding to saturation pressure of ammonia at an evaporator temperature ranging from −5 ℃ to 15 ℃ during adsorption. The desorption process is simulated at different regeneration temperatures with a required desorption pressure of 17.28 bar corresponding to saturation pressure at condenser operating temperature of 40 ℃. The average cooling power produced in first 60 min of system operation at an evaporator temperature of −5 ℃ is 4.89 W, 207 W, 206 W and 925 W with the use of BaCl2, CaCl2, SrCl2 and MnCl2 composites respectively. The theoretical maximum coefficient of performance (COP) obtained are 0.31, 0.365, 0.308 and 0.552 with BaCl2, CaCl2, MnCl2 and SrCl2 respectively. The cooling power (CP) is increasing with increase in evaporator temperature. The shortest adsorption completion time is observed at 15 ℃ of evaporator temperature with all metal halides used. The lowest adsorption time is observed with MnCl2 composite salt and highest with BaCl2 composite salt. The regeneration time of all composite salt beds is decreasing with increase in regeneration temperature.

Alginate functionalized sugarcane cellulose-based beads to improve methylene blue adsorption from aqueous solution

The study was carried out with the goal of synthesizing composite bead of cellulose, chitosan functionalized by sodium alginate using as an efficient and applicable adsorbent for methylene blue removal. Fabricating parameters of the material synthesis process like cellulose mass, sodium hydroxide concentration, immersing time and sodium alginate concentration were assessed in detail. The dye adsorption performance in water under the influence of pH, contact time, dye initial concentration, the material mass, shaking speed, temperature was also thoroughly evaluated. The results of advanced analyses showed that the beads were successfully synthesized with a rough surface and mesoporous structure. The adsorption isotherm and adsorption kinetics of dye adsorption process exhibited that the process was consistent with the Freundlich adsorption isotherm and the pseudo-second-order kinetic model, indicating a favorable physical adsorption process with multilayer of the dye on the adsorbent surface. The intra-particle diffusion model showed the strong dye adsorption by the beads occurred during the first two and half hours. The adsorbent could maintain its adsorption performance of 86 % for three times of regeneration. Finally, this study provided a recyclable and effective adsorbent for dyes separation from water.

Dynamic borate ester bond reinforced hydroxyethyl cellulose/corn starch crosslinked film for simple recycling and regeneration

Endowing biodegradable plastics with easy recyclability can reduce competition with food resources and further enhance their environmental friendliness. In this work, 4-carboxyphenylboronic acid was grafted onto the side chains of hydroxyethyl cellulose and compounded with inexpensive cornstarch. Upon the introduction of tannic acid, stable and reversible borate ester bond rapidly formed, yielding composite biodegradable plastic films with outstanding mechanical properties and facile recyclability. The formation of a dynamic cross-linked network mitigates the aggregation of gelatinized starch molecules, enhancing the flexibility and durability of the crosslinked film. Testing revealed that while maintaining high tensile strength, the elongation at break of the crosslinked film increased by 952.86 %. The static water contact angle was improved from 32.74° to 78.82°, with a change of <5° within 1 min, demonstrating enhanced water resistance. Excellent antioxidant and thermal stability were also characterized, the crosslinked film can be easily dissolved by heating in water at pH = 6.5 and reshaped in water at pH = 7.2. After five times of regeneration, the tensile strength loss was as low as 5.68 %. This eco-friendly and efficient recycling process is promising during green chemistry.

Biomimetic multi-channel nerve conduits with micro/nanostructures for rapid nerve repair

Peripheral nervous system (PNS) injuries often lead to significant sensory and motor impairments. Traditional artificial nerve conduits, lacking anisotropic structures, have been associated with prolonged repair time and failures in nerve regeneration. This study aimed to address these challenges by developing a novel approach for rapid repair of peripheral nerve injuries (PNI). A 3D oriented fibers scaffold featuring distinct radial (RFs) and longitudinal (LFs) fibers orientations was engineered using coaxial electrospinning and gas directional foaming techniques. This scaffold was then integrated with a shape memory conduit to form a directional multi-channel nerve conduit with micro/nanostructures. The results revealed that the grooved surface of the fibers significantly improved cellular directional guidance, effectively facilitating the migration of SCs from the periphery towards the center and from the base to the apex of the scaffold. In a rat model with a 10 mm nerve defect, the ND-PLATMC/LF ND-PCL scaffold significantly enhanced nerve regeneration and motor function recovery within 4 weeks. These results suggest the potential of this innovative scaffold for efficient repair of the nerve injuries.

Real-time distributed observing on regeneration rates of an apodized type I fiber Bragg grating

Regenerated fiber Bragg gratings (RFBGs) have garnered widespread attention owing to their fascinating high-temperature resistance. The flexible modulating refractive index of fiber Bragg gratings (FBGs) is conducive to boost the versatility of RFBG fabrication. Nevertheless, the impact of different refractive index modulation (RIM) amplitudes on regeneration rate remains ambiguous. Given this, an optical low-coherence reflectometry (OLCR) is employed for real-time monitoring of RIM during the regeneration process. Experimental results illustrate the regeneration rate remains consistent at different RIM amplitudes. Furthermore, a functional relationship between regeneration ratio and regeneration time is proposed. To enhance the OLCR signal intensity, a promising optimized strategy is raised by introducing a phase shift at the edges of FBG. This work deepens our understanding of the FBG regeneration process and immensely improves the manufacturing flexibility of RFBG.

Soil fauna changing in after‐pine harvesting's areas along a temporal gradient of Atlantic Forest regeneration

AbstractMonoculture of pine alters the soil fauna community structure, but forest farms, mixed with natural areas, are restoring the original vegetation to protect, the diversity and ecosystem functions. In restoration initiatives it is necessary to consider the soil fauna. Thus, the aim of this study was to investigate how the process of restoration of the soil community occurs over time in areas after pine harvesting. Areas in natural regeneration with 4 and 10 years, pine plantations adjacent to these areas (representing previous use), and areas of natural forest (reference) were evaluated, it was evaluated three areas per treatment, with six sampling points spaced 30 m apart, totalling 18 sampling points for each treatment (n = 18). Soil mesofauna and macrofauna were collected through soil monoliths and pitfall traps. The comparison of the statistical analysis was to check for changes in the soil fauna over time (4 and 10 years) compared with that observed in secondary forest areas. The study showed that, along the natural regeneration time (4 and 10 years), it was observed increments in the diversity and evenness of the soil community and a reduction in the dominance of groups like Formicidae and increases in the community structure complexity with the resurgence of micropredators/regulators (Collembola and Acari), litter transformers (Oligochaeta, Diplopoda, Blattodea, Coleoptera (Larva), Diptera (Larva) and Coleoptera) and predators (Pseudoscorpiones, Opiliones, Symphyla and Coleoptera) after 10 years of natural regeneration, the areas have already recovered groups with important ecosystem functions, but are not yet at the level of abundance, functional diversity and community structure of native forest areas. The 4‐ and 10‐year regeneration areas present major number of soil fauna groups of native forest (20 groups in regeneration areas and 17 in the native forest areas). Even so, the forest showed a major complexity of soil fauna community structure, evidenced by the diversity. This study contributes to the understanding of natural regeneration for soil fauna along a temporal gradient and these findings can guide the conservation of regional soil fauna diversity.

Ten years’ experience of vacuum systems in treatment of complicated postoperative wounds of various etiologies

Objective: increase effectiveness of wounds treatment after various etiology by using VAC.Materials and methods: study included 128 patients with surgical infection. Specter of operations is presented: pilonidal cyst excision — 40 (31.2%), sternomediastinitis — 23 (18%), mesh hernioplasty — 16 (12.5%), laparotomy — 15 (11.7%), emergency laparotomy — 7 (5.5%), traumatology paraimplant complications — 7 (5.5%), abdominoplasty — 7 (5.5%), postoperative esophageal fistulas — 6 (4.7%), decubital ulcers — 4 (3.1%), mammoplasty — 3 (2.3%).Results: duration of VAC-therapy averaged 22.1±0.26 days. Systemic inflammatory reaction noted in 43 (33.6%) patients. Granulation tissue on 8th day of treatment noted in 98 (76.6%) cases. Microscopically, on day 8 of treatment, inflammatory-regenerative cytograms were detected in 104 (81.3%) patients. Over the course of 16 days, wounds decreased by 62.1±2.5% in all observations. In 47 (36.7%) cases, secondary sutures were applied, in 30 (23.4%) — grafting. A month later, healing was noted in 106 (82.8%) patients. Complications (wound bleeding) were noted in 7 (5.5%) patients. Reoperations were performed in 11 (8.5%) patients. Period of complete healing was 29.3±0.4 days.Conclusions: vacuum therapy is an effective way to treat wounds in purulent surgery. Time of complete reparative regeneration of wound and period of expensive inpatient treatment are reduced.

Chemiresistive NH3 and H2S sensors based on thin films of vitamin B12 derivatives

Despite the large number of materials, e.g. semiconducting oxides, carbon nanomaterials, conducting polymers and others, that are used as active layers of chemiresistive sensors to ammonia and hydrogen sulfide, the search for new materials remains an urgent task. Special attention is paid to the search for environmentally friendly materials. Corrinoids are naturally occurring coordination complexes consisting of a central cobalt ion and a tetrapyrrole ligand called a corrin ring. Cobalamins and their derivatives are widely used as active layers of optical and electrochemical sensors. At the same time, vitamin B12 derivatives have not been studied as active layers of chemiresistive gas sensors. In this work, films of two vitamin B12 derivatives, viz. dicyanocobyrinic acid heptabutyl ester (DC) and its aquacyano form, aquacyanocobyrinic acid heptabutyl ester (AC), deposited by spin coating and drop casting techniques onto interdigitated electrodes, were tested for the first time as active layers of chemiresistive sensors for the detection of low concentrations of ammonia and hydrogen sulfide (1–50 ppm) in air. It was shown that films of both vitamin B12 derivatives demonstrated reversible sensor response to NH3 and H2S at room temperature. The limit of detection (LOD) of H2S was 0.1 ppm for both vitamin B12 derivatives, while LOD of ammonia was noticeably lower (0.06 ppm) in the case of AC films than in the case of DC films (0.4 ppm). Both sensors demonstrated a fairly low regeneration time, which did not exceed 180 s for 5 ppm of NH3 and 185 s for 5 ppm of H2S.

Enhancing sustainability in sewage treatment: A least squares support vector regression-based modeling approach for optimizing regeneration conditions of iFeCu

Nanoparticles in wastewater treatment offer sustainable, efficient removal of persistent pollutants, with minimal resource usage and reusability. This study examines the reusability of immobilized iron‑copper nanoparticles (iFeCu) for sewage treatment. The effect of the regeneration condition of iFeCu including the regeneration time and temperature on the performance of iFeCu for sewage treatment was investigated. Moreover, a soft sensor model, namely principal component analysis discrimination analysis ensemble least squares support vector regression (PCA-DA-E-LSSVR) model was developed to predict the performance of iFeCu, and an online performance of the model was studied to evaluate its accuracy. Investigating regeneration conditions like time and temperature, it was found that iFeCu regenerated in 1 mol (M) sodium carbonate (Na2CO3) at 40 °C for 5 h performed comparably to that regenerated at 60 °C for 15 h. Higher regeneration temperatures (>40 °C) decreased carbon dioxide and monoxide emissions but reduced ammonia (NH3) removal by ∼22 %. Shorter regeneration times (<5 h) decreased Na2CO3-iFeCu interaction, leading to an ∼11 % NH3 removal reduction. The correlation coefficient, R2 value of 0.8514 was obtained for the proposed PCA-DA-E-LSSVR model. Overall, the developed model well-fits the nonlinear data in sewage treatment and provides acceptable ranges of online performance results.

The impact of PAC-loaded polymer membrane thickness on chloroform removal and comparison of solvent and thermal membrane regeneration methods.

Powdered activated carbon (PAC) has better adsorption performance than granular activated carbon (GAC) and is widely used in water purification. In most cases, PAC is dosed into water directly, then precipitated as sludge, and landfilled. In this study, PAC was mixed with a polymer and dissolved in dimethylformamide (DMF) solvent to form a PAC-loaded membrane, which was then tested for chloroform removal. The chloroform adsorption capacity of the PAC membrane increased with increasing membrane thickness because of higher carbon loading. However, regardless of membrane thickness, the flux of the PAC membranes was similar since flux resistance predominantly occurred at the top dense polymer surface. This dense surface can be removed by sandpaper polishing, where the adsorption capacity of the polished PAC membranes was 20% higher than the unpolished membranes because of more even distribution of feed water on the polished surface. Removal of the dense surface via polishing increased the flux by 97% to 130%, exceeding the flux of typical household carbon block filters. Using DMF to regenerate the membrane recovered 48% to 66% of the initial adsorption capacity. Thermal regeneration of the exhausted PAC membrane at 250°C was more effective than DMF regeneration (both in terms of cost and performance), with 83% to 94% PAC membrane regeneration efficiency over four regeneration recycles. After four thermal regeneration cycles, flux increased by 300% and the membrane became brittle because of thermal aging of the polymer, indicating that a total of 6h of regeneration time (equivalent to three cycles in this study) was the limit for effective PAC membrane performance. PRACTITIONER POINTS: Powdered activated carbon was immobilized on a membrane to remove chloroform from water. Thicker membranes increased adsorption capacity but did not impact flux. Flux and capacity increased using polishing to remove the dense polymer surface and more evenly distribute flow across the membrane. Thermal regeneration of the membrane at 250°C was effective for up to three cycles and outperformed solvent-based regeneration. PAC-loaded filters are relevant for applications such as household carbon block filtration.

RECOVERY OF THE ORGANIC SOLVENTS FROM THE MULTICOMPONENT MIXTURE IN THE PROCESS OF THE FRACTIONAL DISTILLATION AND THE VACUUM DISTILLATION

In these times of sustainability, the purification and regeneration of used solvents is attracting a lot of interest for environmental reasons and to reduce production costs. The article presents research on the separation of organic solvents such as acetonitrile, methanol, acetone, and toluene from a multicomponent mixture of liquid organic waste. This is an element of the circular economy and prevents the emission of volatile organic compounds into the environment. In order to separate the mixture and recover the solvents, fractional distillation and vacuum distillation were used together with pre-treatment of the waste using sorption on silica gel and calcium oxide. The analysis of the waste composition and the mixture after the separation was performed by gas chromatography coupled with a mass spectrometer (GC-MS). As a result of the research, the acetonitrile concentration increased to 90.7% after fractional distillation.

Cell-based medicinal products: a review of current research

INTRODUCTION. Cell therapies and tissue-engineered products are aimed at patients with severe conditions (genetic and neurodegenerative disorders, cancers, musculoskeletal injuries, burns, etc.) that lack alternative treatment options. Analysis of clinical efficacy data on cellbased medicinal products is important for understanding their translational potential in personalised medicine.AIM. This study aimed to review key trends in cell therapy, analyse data on approved cell therapies and tissue-engineered products, and assess challenges and prospects for their use.DISCUSSION. This article analyses data on the composition of cell therapies and tissue-engineered products, indications for their use, and the results of clinical studies. Cell-based medicinal products are derived from autologous or allogeneic mesenchymal and limbal stem cells, epithelial cells, chondrocytes, native or genetically engineered haematopoietic stem cells, genetically engineered lymphocytes (CAR-T, CAR-NK), etc. Medicinal products based on cell technologies have been approved in many countries, including the USA (approximately 30), the European Union (approximately 20), Japan (18), South Korea (15), etc. As of today, two cell therapies have been granted marketing authorisation in the Russian Federation. The first is based on CAR-T cells (a gene therapy product), and the other is based on chondrocytes (a cell-based medicinal product); the latter has been developed in Russia. The main advantages of cell therapy products include higher efficacy and fewer adverse drug reactions in comparison with standard treatment modalities. The main challenges of cell therapy include the risks of immune reactions and mutagenesis associated with lentiviral vectors or CRISPR/Cas9 technology, as well as limited efficacy of CAR-T and CAR-NK cells due to immunosuppressive properties of tumour microenvironment.CONCLUSIONS. In comparison with conventional treatment approaches, the use of cell therapies and tissue-engineered products can help effectively eliminate defects in various body tissues, avoid highly invasive surgical interventions, and reduce regeneration time. Thus, ensuring development of similar but at the same time more affordable Russian medicinal products can bring great benefits for the healthcare system of the Russian Federation.

Study on the active regeneration characteristics of DPF in diesel-methanol dual-fuel engine under different exhaust oxygen concentrations

This study proposes a method to control exhaust oxygen (O2) concentration by adjusting the intake throttle valve, achieving intake throttling, and reducing intake airflow. The impact of exhaust O2 concentration at the inlet of the diesel oxidation catalyst (DOC) the diesel particulate filter (DPF) performance during active regeneration in diesel engines is investigated. Experiments are conducted under methanol substitution rates (MSR) of 0% and 20% to investigate how different exhaust O2 concentrations affect the performance of the DOC and DPF during active regeneration. A comparative analysis of fuel consumption and cumulative CO2 emissions during DPF active regeneration under different exhaust O2 concentrations is performed. Research results indicate that decreasing exhaust O2 concentration reduces exhaust flow, raising DOC inlet temperature. This enhancement improves catalytic conversion efficiency, accelerating the rise in DPF inlet temperature. The average conversion efficiency of DOC to unburned methanol exceeds 98.07%. After initiating DPF active regeneration, O2 concentration sharply drops, leading to elevated CO2 emissions. As soot combustion advances, the required O2 diminishes, resulting in a gradual rise and eventual stabilization of O2 emissions. Economically and environmentally, irrespective of MSR (20% or 0%), there exists an optimal exhaust O2 concentration that minimizes effective regeneration time during DPF active regeneration, achieving minimal fuel consumption and the lowest CO2 mass emissions. This study offers theoretical support for optimizing energy-saving and emission-reduction processes during DPF active regeneration.

Resorbable engineered barrier membranes for oral surgery applications.

Population aging, reduced economic capacity, and neglecting the treatments for oral pathologies, are the main causal factors for about 3 billion individuals who are suffering from partial/total edentulism or alveolar bone resorption: thus, the demand for dental implants is increasingly growing. To achieve a good prognosis for implant-supported restorations, adequate peri-implant bone volume is mandatory. The Guided Bone Regeneration (GBR) technique is one of the most applied methods for alveolar bone reconstruction and treatment of peri-implant bone deficiencies. This technique involves the use of different types of membranes in association with some bone substitutes (autologous, homologous, or heterologous). However, time for bone regeneration is often too long and the bone quality is not simply predictable. This study aims at engineering and evaluating the efficacy of modified barrier membranes, enhancing their bioactivity for improved alveolar bone tissue regeneration. We investigated membranes functionalized with chitosan (CS) and chitosan combined with the peptide GBMP1α (CS + GBMP1α), to improve bone growth. OsseoGuard® membranes, derived from bovine Achilles tendon type I collagen crosslinked with formaldehyde, were modified using CS and CS + GBMP1α. The functionalization, carried out with 1-ethyl-3-(3 dimethylaminopropyl)carbodiimide and sulfo-N-Hydroxysuccinimide (EDC/sulfo-NHS), was assessed through FT-IR and XPS analyses. Biological assays were performed by directly seeding human osteoblasts onto the materials to assess cell proliferation, mineralization, gene expression of Secreted Phosphoprotein 1 (SPP1) and Runt-Related Transcription Factor 2 (Runx2), and antibacterial properties. Both CS and CS + GBMP1α functionalizations significantly enhanced human osteoblast proliferation, mineralization, gene expression, and antibacterial activity compared to commercial membranes. The CS + GBMP1α functionalization exhibited superior outcomes in all biological assays. Mechanical tests showed no significant alterations of membrane biomechanical properties post-functionalization. The engineered membranes, especially those functionalized with CS + GBMP1α, are suitable for GBR applications thanks to their ability to enhance osteoblast activity and promote bone tissue regeneration. These findings suggest a potential advancement in the treatment of oral cavity problems requiring bone regeneration.

Complete series method (CSM): a convenient method to reduce daily heterogeneity when evaluating the regeneration time (RT) of insecticide-treated nets (ITNs)

Background“Regeneration time” (RT) denotes the time required to obtain a stable mortality rate for mosquitoes exposed to insecticide-treated nets (ITNs) after three consecutive washes of a net in a day. The RT informs the wash interval used to artificially age ITNs to simulate their lifetime performance under user conditions (20 washes). RT was estimated following World Health Organization (WHO) longitudinal method (LM) procedures. Longitudinal evaluation may introduce heterogeneity due to mosquito batch variability, complicating RT determination. To overcome this, nets at each stage of regeneration (i.e., 1, 2, 3, 5 and 7 days post wash) were prepared in advance and refrigerated; then, a complete regeneration series was tested with a single mosquito batch on 1 testing day, completing four series over 4 days. This study compared the complete series method (CSM) against the LM.MethodsThe overall heterogeneity in the methods for estimating RT of one incorporated alpha-cypermethrin and piperonyl butoxide (PBO) and one incorporated permethrin with PBO ITNs was determined using laboratory-reared resistant Anopheles arabiensis under standard laboratory conditions. LM methods and CSM were compared in two experiments with refrigerated nets acclimated for (i) 2 h (test 1) and (ii) 3 h (test 2). Four regeneration replicates per day were tested per ITN product with 50 mosquitoes exposed per replicate (equivalent sample size to LM). The heterogeneity from these methods was compared descriptively.ResultsThe intra-method variability for unwashed pieces was minimal, with variance of 1.26 for CSM and 1.18 for LM. For unwashed nets, LM had substantially greater variance and ratio of LM:CSM was 2.66 in test 1 and 2.49 in test 2. The magnitude of mortality measured in bioassays depended on sample acclimation after refrigeration.ConclusionsThe CSM is a convenient method for determining the regeneration times. ITNs are prepared in advance, reducing pressure to prepare all samples to start on a single day. A complete regeneration series of samples is removed from the refrigerator, defrosted and evaluated on a single day with one mosquito batch reducing the influence of mosquito batch heterogeneity on results. Replicates can be conducted over several days but do not have to be conducted on consecutive days, allowing easy facility scheduling.Graphical

Adsorption properties of Pb(II) and Cd(II) in acid mine drainage by oyster shell loaded lignite composite in different morphologies

A new idea to alleviate environmental pollution is the development of low-cost adsorbents using natural minerals and fishery wastes to treat high concentrations of heavy metal pollutants in acid mine drainage (AMD). Adsorbent morphology, adsorptive and regenerative capacity, and application potential are limiting factors for their large-scale use. Oyster shells capable of releasing alkalinity were loaded on the surface of lignite to develop two composite adsorbents with different morphologies (powdery and globular) for the treatment of AMD containing Pb(II) and Cd(II). The results show that the ability of the adsorbent to treat AMD is closely related to its morphologies. The pseudo-second-order kinetic model and the Langmuir model are suitable to describe the adsorption process of OS-M(P), and the maximum adsorption saturation capacities of Pb(II) and Cd(II) are 332.6219 mg/g and 318.9854 mg/g, respectively. The pseudo-second-order kinetic model and the Freundlich model are suitable to describe the adsorption process of OS-M(G). A synergistic result of electrostatic adsorption, neutralization precipitation, ion exchange and complex reaction is achieved in the removal of Pb(II) and Cd(II) by two morphologies of adsorbents. The regeneration times (5 times) and recovery rate (75.75%) of OS-M(G) are higher than those of OS-M(P) (3 times) and recovery rate (20%). The ability of OS-M(G) to treat actual AMD wastewater is still better than that of OS-M(P). OS-M(G) can be used as a promising environmentally friendly adsorbent for the long-term remediation of AMD. This study provides a comprehensive picture of resource management and reuse opportunities for natural mineral and fishery wastes.

Investigation of the impacts of regeneration temperature and methanol substitution rate on the active regeneration of diesel particulate filter in a diesel-methanol dual-fuel engine

Methanol (CH3OH), a sustainable fuel derived from many renewable resources, simultaneously reduces nitrogen oxides (NOx) and particulate matter (PM) in diesel-methanol dual-fuel engines. This study systematically investigated the effects of regeneration temperature and methanol substitution rate (MSR) on the performance of diesel oxidation catalyst (DOC), diesel particulate filter (DPF), and the temperature characteristics of DPF substrate during active regeneration. The experimental results show that the DOC catalytic oxidation of unburned CH3OH has a conversion rate of more than 97.5 % across various MSR. DPF inlet temperature rose faster with higher MSR. Elevated regeneration temperature reduced effective regeneration times and diesel equivalent consumption. Within active regeneration conditions with MSR increases, both effective regeneration times and diesel equivalent consumption initially decreased and then increased as the MSR rose. At MSR = 30 %, the duration of effective regeneration times during DPF active regeneration was minimized, and diesel equivalent consumption at MSR = 30 % experienced an improvement of 22.52 % compared to MSR = 0 %. The highest DPF substrate temperatures across various MSR levels are consistently observed at T6 position within the DPF. This study can provide a theoretical basis for the active regeneration of DPF in methanol-diesel dual-fuel mode.

CT reconstruction based 3D model of the digital cushion's blood supply in the hind foot of an African savanna elephant (Loxodonta africana).

Foot health is crucial for elephants, as pathological lesions of the feet are a leading cause of euthanasia in captive elephants, which are endangered species. Proper treatment of the feet, particularly in conditions affecting the digits and the digital cushion, requires a thorough understanding of the underlying anatomy. However, only limited literature exists due to the small population and the epidemiological foot diseases which often precludes many deceased elephants from scientific study. The aim of this study was to provide a detailed anatomical description of the blood supply to the African elephant's hindfoot. The healthy right hindlimb of a 19-year-old deceased female African savanna elephant was examined using computed tomography. Following a native sequence, 48 mL of barium-based contrast agent was injected into the caudal and cranial tibial arteries, and a subsequent scan was performed. The images were processed with 3D Slicer software. The medial and lateral plantar arteries run in a symmetrical pattern. They each have a dorsal and a plantar branch, which reach the plantar skin before turning toward the axial plane of the sole to reach the digital cushion from the proximal direction. An accurate 3D model of the arteries and the bones of the foot, a set of labeled images and an animation of the blood supply have been created for ease of understanding. In contrast to domestic ungulates, the digital cushion of the hindlimb is supplied differently from that of the forelimb. The lack of large vessels in its deeper layers indicates a slow regeneration time. This novel anatomical information may be useful in the planning of surgical interventions and in emergency medical procedures.