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Cryopreservation is pivotal for conserving genetic diversity. This study aimed to optimize cryopreservation techniques for Dandarawi rooster sperm through two experiments. Experiment I explored the optimal levels of two cryoprotectants, with or without sucrose, in two trials. Semen from 20 Dandarawi males was pooled, diluted, and divided into five aliquots. In trial 1, one aliquot remained fresh (control), while others were frozen in straws using glycerol (GLY) at concentrations of 8% and 11%, with or without 5% sucrose. In trial 2, one aliquot served as a control, while the others were frozen in pellets using a cryo-diluent containing 5% or 7% dimethylacetamide (DMA), with or without sucrose. Danadarawi hens (n=10 per group) were inseminated with fresh (control) or frozen-thawed sperm, with six repetitions of semen collection and insemination. In Experiment II, pooled semen was similarly divided. Aliquot 1 served as a control, while aliquots 2 and 3 were frozen in pellets with 5% DMA cryo-diluent, with and without 5% sucrose, respectively. Aliquots 4 and 5 were frozen in straws with 8% GLY, with and without 5% sucrose. Transmission electron microscopy (TEM) evaluated spermatozoa for cryodamage. GLY level did not significantly affect motility, fertility, or hatchability, but sucrose notably improved hatchability with 8% and 11% GLY. DMA did not significantly impact motility, although 7% DMA demonstrated the highest fertility. Sucrose enhanced hatchability with 5% DMA but not with 7% DMA. TEM analysis revealed higher levels of acrosomal damage in spermatozoa frozen with GLY compared to DMA, with sucrose consistently mitigating acrosomal injuries. Moderate damage was observed in the tail, sparing the nucleus and midpiece. In conclusion, the choice of freezing method and the inclusion of sucrose significantly influenced sperm freezing outcomes, demonstrating their critical roles in preserving sperm quality. Sucrose was particularly effective across all treatments, notably in protecting the acrosome region. [ABSTRACT FROM AUTHOR]

The present study evaluated the cryoprotectant efficacy of dimethylacetamide (DMA) and ethylene glycol in a one-step protocol to freeze boar sperm. The sperm-rich portion of the ejaculates from two boars were collected once a week, for 10 weeks. After collection, the ejaculates were diluted (1:1; v/v) in the cooling extender. After determining their spermatozoa concentration, the ejaculates were pooled with the same number of spermatozoa from each boar and stabilized at 20°C for 120 min. Distinct cryoprotectants were added to the cooling extender at 20 °C, at different concentrations, composing six treatments: 1.25% and 2.5% glycerol (control); 1.25% and 2.5% ethylene glycol; 2.5% and 5.0% DMA. The samples were stored in 0.25 mL straws, containing 35 × 106 spermatozoa. After 90 min at 20 °C, the straws were submitted to a cooling curve until 5 °C (0.3 to 0.5 °C/min) and kept at 5°C for 60 min. Freezing was conducted by placing the straws horizontally 5 cm above the liquid nitrogen for 10 min, followed by immersion on liquid nitrogen. After thawing at 37 °C for 30 seconds, sperm quality was evaluated through a computer-assisted semen analysis system and flow cytometry. Sperm motility was greater (P< 0.05) in treatments with 5.0% and 2.5% DMA (22.2 ± 2.6% and 20.0 ± 2.8%, respectively) than in treatment with 2.5% ethylene glycol (8.2 ± 1.0%). The integrity of the plasma membrane (P = 0.08) and mitochondrial membrane potential (P = 0.27) was similar among the treatments. The treatment with 2.5% ethylene glycol was the least efficient to maintain intact acrosome membrane (P< 0.01). Some kinetics parameters (DAP, DCL, DSL, VAP, VCL, VSL e ALH) were positively affected by 5.0% DMA. The one-step freezing protocol resulted in unsatisfactory boar sperm motility after thawing, regardless of the cryoprotectant. [ABSTRACT FROM AUTHOR]

In the title compounds, N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol tribromide (1/1), C4H9NO·C4H10NO+·Br3− or [(C4H9NO)·(C4H10NO)](Br3), (I), N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol dibromidoiodate (1/1), C4H9NO·C4H10NO+·Br2I− or [(C4H9NO)·(C4H10NO)](Br2I), (II), and N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol dichloridoiodate (1/1), C4H9NO·C4H10NO+·Cl2I− or [(C4H9NO)·(C4H10NO)]·(Cl2I), (III), all the anions are almost linear in geometry and all the cations, except for the methyl H atoms, are essentially planar. In the crystal structure of (I), the cations are linked by pairs of C—H...O hydrogen bonds, forming inversion dimers with an R22(8) ring motif. These dimers also exhibit O—H...O hydrogen bonding. Dimerized cation pairs and anions are arranged in columns along the a axis. In the crystal of (II), the cations are linked by pairs of O—H...O and C—H...O hydrogen bonds, forming an R44(14) ring motif. These groups of cations and the anions form individual columns along the a axis and jointly reside in planes roughly parallel to (011). In the crystal of (III), cations and anions also form columns parallel to the a axis, resulting in layers parallel to the (020) plane. Furthermore, the crystal structures of (I), (II) and (III) are consolidated by strong halogen (Br and/or I and/or Cl)...H and weak van der Waals interactions. In addition to the structural evaluation, a Hirshfeld surface analysis was carried out.

The main objective of our research described here was to determine the viscometric properties of polysaccharide solutions of sodium carboxymethyl cellulose (CMC) in dimethylacetamide (DMA)/acetone (A) mixtures. The evolution of the dynamic and intrinsic viscosities and the effect of the intrinsic Gibbs energy of CMC in DMA/A (44 ml/6 ml) were characterized as a function of the temperature (293.15 to 318.15) K, and concentration (1 to 10) g/l. We identified four main concentration regimes, corresponding to an absorption regime, a dilute regime, a critical regime, and the semi-dilute regime. The thermodynamic parameters of the viscosity also supported the obtained results. Exploiting our results, CMC/DMA/A is a promising solvent mixture for use in pharmaceutical and antibacterial applications. [ABSTRACT FROM AUTHOR]

The key role of a cryoprotectant is to minimize the chemical and physical stress which occurs during cooling, freezing and thawing of semen. The difference between the cryoprotectant (CPA) occurs in their permeability coefficient and the structural model of the cryogenic agent. The beneficial effect of dimethylacetamide (DMA) as a cryoprotectant especially for sperms had been observed in several studies. The aim of the study was to study the cryoprotective effect of DMA in freezing the Malabari buck semen compared to glycerol. Ten ejaculates were taken from fourMalabaribucks . After preliminary evaluation sample split technique was followed with Tris based extender containing glycerol (6.7 per cent) as cryoprotectant (control) and Trisextender containing DMA (3 per cent) as cryoprotectant (treatment group). The semen straws (0.25mL) after filling were subjected for equilibration and manual freezing. Sperm kinetics was studied using computer-aided sperm analyzer. Pre-freeze and post-thaw evaluation included sperm viability, sperm abnormality, hypo osmotic test, acrosome integrity test and DNA fragmentation. Results indicated that inclusion of 6.7 per cent glycerol had significantly higher (p

Simple Summary: Semen cryopreservation remains the most applicable methodology for conserving and transmitting superior genetic backgrounds in poultry species. However, there is wide variability in the results of sperm viability and fertility due to susceptibility to cryodamage. The current study implemented a cryopreservation protocol based on rapid freezing of semen pellets supplemented with various levels of dimethylacetamide (DMA), focusing on in vitro quality, computer-assisted-sperm-analysis (CASA), and anti-freeze-associated gene expression of post-thawed rooster sperm. The current investigation provides novel results regarding the appropriate concentration and molecular mechanism by which DMA could be supplemented to frozen semen pellets and used as a successful protocol for sperm cryopreservation in poultry species. Sperm cryopreservation is an effective technique for conserving animal genetic diversity and transmitting superior genetic backgrounds, maintained via a non-invasive sampling and collection of huge quantities of sperm. Nevertheless, cryopreservation in avian species is not commercially viable because of the rooster sperm's susceptibility to damage. This study aims to estimate the impact of dimethylacetamide (DMA) as a cryoprotectant at different levels (3%, 6%, or 9%) on the post-thawed sperm quality, motility, antioxidant-biomarkers, and the expression of anti-freeze related genes. Semen samples were collected twice a week from twelve roosters aged 40 wk, weighing 3400 ± 70 g, and belonging to the Cairo-B2 chicken strain. Fresh semen samples were rapidly appraised, pooled, diluted with two volumes of a basic extender, and divided equally into three groups. The diluted groups were chilled at −20 °C for 7 min, then gently supplemented with 3, 6, or 9% pre-cooled DMA and equilibrated at 5 °C for a further 10 min. Semen pellets were formed by pipetting drops 7 cm above liquid nitrogen (LN2), which were then kept inside cryovials in the LN2. Thawing was performed 2 months later by taking 3–4 pellets of the frozen semen into a glass tube and warming it in a water bath for 8 s at 60 °C. The results showed that 3% DMA increased the proportion of total motile sperm, progressivity, viability, and plasma membrane integrity (%) compared to the 6% and 9% DMA groups. The lipid peroxidation and antioxidant enzyme activity were improved in the 3% group. At the same time, some anti-freeze-related genes' (including ras homolog family member A (RHOA), heat shock protein 70 (HSP70), and small nuclear ribonucleoprotein polypeptide A (SNRPA1)) expressions were upregulated within the 3% DMA group relative to other groups. In conclusion, the 3% DMA group maintained higher post-thawed sperm quality than the other tested groups. [ABSTRACT FROM AUTHOR]

Wastewater from factories producing polysulfone-based membranes mainly contains the used organic solvent, i.e., dimethylacetamide (DMAc). Due to the environmental impact of DMAc, wastewater treatment is mandatory. Several biological treatment options based on the activated sludge process are described in the literature. Due to artificial aeration, these techniques have high energy requirements. Near-nature processes such as vertical flow constructed wetlands (VF wetlands) have a low energy demand, high tolerance to load fluctuations, and low maintenance requirements. Therefore, high-loaded, two-stage VF wetlands are an efficient option for treating wastewater. However, constructed wetlands have so far only been used to a limited extent for the treatment of industrial wastewater. In the present study, the ability of laboratory-scale, high-load, two-stage VF wetlands to treat DMAc was investigated. This included their DMAc degradation efficiency and corresponding pathways, removal of the total organic carbon (TOC), nitrification and denitrification of the nitrogen, as well as the ecotoxicological effects (mutagenicity, genotoxicity, reactive oxygen species) of untreated and treated wastewater. The focus was to determine the effect of different grain size distributions on removal rates, the maximum inflow loading, and the effect of high inflow concentrations on effluent concentrations. In general, DMAc was completely degraded using VF wetlands, with dimethylamine (DMA) identified as the main intermediate. TOC removal rates reached more than 99%. The nitrogen bound to DMAc was completely nitrified. However, the start-up of the VF wetlands without seeded filter material temporarily leads to high nitrite accumulation. This may affect the mutagenicity of the treated wastewater. The results show that high-loaded, two-stage VF wetlands are an effective option for treating wastewater containing DMAc with higher efficiency than comparable biological processes. [ABSTRACT FROM AUTHOR]

Occupational exposure to dimethylacetamide (DMAc) has been reported to cause toxic hepatitis. Sixty spandex workers were included in this study to research the clinical manifestations and expression of cytokines and lymphocytes in DMAc-induced toxic hepatitis. Chinese drugs (reduced glutathione and Hugan tablets) were used to treat them. The manifestations including jaundice, asthenia, appetite, nausea, emesis, abdominal distension, yellow urine, and dizziness were scored. The percentages of patients rated as 0–3, 4–6, 7–9, and 10–12 points were 33.3%, 43.3%, 21.7%, and 1.7%, respectively, before treatment, and all patients showed 0–3 points after the treatment. The ultrasonic and CT imaging revealed diffuse intrahepatic hypodensity, intrahepatic calcification, signs of liver injury, and splenomegaly, which improved after therapy. Blood analysis showed that ALT, AST, TBIL, IL-6, IL-10, TNF-α, IFN-γ, CD3+%, and CD4+/CD8+ statistically decreased after drug treatment. Correlation analysis demonstrated positive linear correlations between ALT and TBIL, AST and TBIL, IL-10 and ATL, IL-10 and AST, IL-10 and TBIL, IFN-γ and IL-6, IFN-γ and TNF-α, and CD3+% and ALT. Pro-inflammatory cytokines and lymphocytes in DMAc-induced toxic hepatitis reflected an active immune state that decreased after treatment. IL-10 may inhibit the immune response in this disease, as a protective mechanism. [ABSTRACT FROM AUTHOR]

ABSTRACT: The present study evaluated the cryoprotectant efficacy of dimethylacetamide (DMA) and ethylene glycol in a one-step protocol to freeze boar sperm. The sperm-rich portion of the ejaculates from two boars were collected once a week, for 10 weeks. After collection, the ejaculates were diluted (1:1; v/v) in the cooling extender. After determining their spermatozoa concentration, the ejaculates were pooled with the same number of spermatozoa from each boar and stabilized at 20°C for 120 min. Distinct cryoprotectants were added to the cooling extender at 20 °C, at different concentrations, composing six treatments: 1.25% and 2.5% glycerol (control); 1.25% and 2.5% ethylene glycol; 2.5% and 5.0% DMA. The samples were stored in 0.25 mL straws, containing 35 × 106 spermatozoa. After 90 min at 20 °C, the straws were submitted to a cooling curve until 5 °C (0.3 to 0.5 °C/min) and kept at 5°C for 60 min. Freezing was conducted by placing the straws horizontally 5 cm above the liquid nitrogen for 10 min, followed by immersion on liquid nitrogen. After thawing at 37 °C for 30 seconds, sperm quality was evaluated through a computer-assisted semen analysis system and flow cytometry. Sperm motility was greater (P< 0.05) in treatments with 5.0% and 2.5% DMA (22.2 ± 2.6% and 20.0 ± 2.8%, respectively) than in treatment with 2.5% ethylene glycol (8.2 ± 1.0%). The integrity of the plasma membrane (P = 0.08) and mitochondrial membrane potential (P = 0.27) was similar among the treatments. The treatment with 2.5% ethylene glycol was the least efficient to maintain intact acrosome membrane (P< 0.01). Some kinetics parameters (DAP, DCL, DSL, VAP, VCL, VSL e ALH) were positively affected by 5.0% DMA. The one-step freezing protocol resulted in unsatisfactory boar sperm motility after thawing, regardless of the cryoprotectant.

Safety requirements for lithium-ion batteries (LIBs) have become increasingly stringent with the rapid development of LIBs. We synthesize composite flame-retardant electrolyte additives (pentafluoroethoxy cyclotriphosphazene and dimethylacetamide) for LIBs to improve the safety performance of LIBs during use. The study tests the electrochemical performance of LIBs whose electrolytes contain the aforementioned additives using an electrochemical workstation and a LIB parameter tester. An experiment on self-extinguishing time is conducted to test the flame retardancy and ionic conductivity of the prepared composite flame-retardant electrolytes. Differential scanning calorimetry (DSC) and thermogravimetry are conducted to test the cathode materials of the LIBs after cycling at different heating rates. Various nonisothermal thermodynamic models are used to analyze the experimental DSC data, and the cathode materials' apparent activation energy and thermodynamic parameters are obtained. Finally, multivariate linear fitting is conducted to simulate the thermal decomposition reaction of the cathode materials. [ABSTRACT FROM AUTHOR]

The key role of a cryoprotectant is to minimize the chemical and physical stress which occurs during cooling, freezing and thawing of semen. The difference between the cryoprotectant (CPA) occurs in their permeability coefficient and the structural model of the cryogenic agent. The beneficial effect of dimethylacetamide (DMA) as a cryoprotectant especially for sperms had been observed in several studies. The aim of the study was to study the cryoprotective effect of DMA in freezing the Malabari buck semen compared to glycerol. Ten ejaculates were taken from four Malabari bucks. After preliminary evaluation sample split technique was followed with Tris based extender containing glycerol (6.7 per cent) as cryoprotectant (control) and Trisextender containing DMA (3 per cent) as cryoprotectant (treatment group). The semen straws (0.25mL) after filling were subjected for equilibration and manual freezing. Sperm kinetics was studied using computer-aided sperm analyzer. Pre-freeze and post-thaw evaluation included sperm viability, sperm abnormality, hypo osmotic test, acrosome integrity test and DNA fragmentation. Results indicated that inclusion of 6.7 per cent glycerol had significantly higher (p<0.05) post-thaw values than DMA. From our study we conclude that 6.7 per cent glycerol was better than 3 per cent DMA in cryopreservation of Malabari buck semen. [ABSTRACT FROM AUTHOR]

Simple Summary: Although sperm cryopreservation has a great potential for application in the poultry industry, it is still very limited at the economical scale due to the low fertility of frozen/thawed avian spermatozoa. Dimethylacetamide (DMA) has been widely employed as a cryoprotectant for the cryopreservation of chicken spermatozoa, but with variable results in motility and fertility. To determine the appropriate concentration of DMA in the chicken semen freezing extender, in vitro sperm quality and motility analyses and in vivo field trials based on the fertility of the frozen/thawed rooster sperm were conducted in the present study. The antioxidant biomarkers and novel anti-freeze-associated genes were also analyzed in the post-thawed sperm. Results conclude that DMA is preferably used at a low concentration to obtain applicable results in sperm motility and fertility after thawing without harming the quality and antioxidant system defense. The current study could highlight the possible molecular mechanisms behind the obtained fertility results of DMA-frozen sperm, especially when artificial insemination is implemented in the poultry industry. Sperm cryopreservation is of great importance for the poultry industry but still needs to be optimized. The high susceptibility of poultry sperm to cryodamage leads to low fertility rates after cryopreservation. Therefore, the present study aimed at evaluating the effect of including a cryoprotectant, dimethylacetamide (DMA), in the chicken semen freezing extenders at a final concentration of 3%, 6%, or 9% on the post-thawed sperm motility, quality, antioxidant biomarkers, anti-freeze gene expression, and fertilizing ability. Results showed that the total motile sperm, progressivity, and viability were quadratically increased (p < 0.05) in the 6% DMA group. The antioxidant enzyme activity and lipid peroxidation were negatively (p < 0.05) affected by the increase in DMA concentration. Furthermore, some anti-freeze-associated genes such as heat shock protein 70 (HSP70) and ras homolog family member A (RHOA) were linearly and quadratically down-regulated (p < 0.05) with the high concentration of DMA. Finally, the fertility and hatchability rates did not indicate statistical differences between DMA groups. It can be concluded that using the low concentration of 3–6% DMA in the freezing semen extender is preferable to obtain acceptable results in the post-thawed sperm quality and fertility. [ABSTRACT FROM AUTHOR]

A classical chicken semen diluent (Lake's 7.1 diluent) was modified to have lowered osmolalities (ranging from 290 to 410 mOsm/kg). The modified medium with physiological osmolality of 325 mOsm/kg allowed cold storage of fresh semen for several days with very little loss of membrane integrity and motility, while high osmolalities inhibited motility. This modified medium was then used as base for freezing medium to test effects of the type and concentration of cryoprotective agent (CPA), and the cooling rate (CR). A number of CPAs (methylformamide, methylacetamide, dimethylformamide (DMF), dimethylacetamide (DMA), diethylformamide, and propylene glycol) were first compared by freezing semen with 0.6 mol/l of the respective CPA at a cooling rate of 250 °C/min. Post-thaw motility and membrane integrity were highest with DMA and DMF. Finally, in more detailed factorial experiments, semen from individual cocks or pooled semen was frozen using CRs of 4, 50, 250, and 440 °C/min and DMA concentrations ([DMA]) of 0.4, 0.6, 1.0, and 1.5 mol/l. Straws from each semen sample x treatment combination were divided for semen assessment at three different research groups for sperm motility, membrane integrity, kinked tails, and DNA fragmentation, using microscopy, computer assisted motility analysis, and flow cytometry. There were clear effects of both CR and [DMA] and their interaction. CRs 50 and 250 °C/min gave best post-thaw sperm performance. Higher DMA concentrations gave better post-thaw membrane integrity, but concentrations above 1.0 mol/l can decrease sperm velocity or even inhibit sperm motility. Therefore [DMA] may best be 0.6–1.0 mol/l at a CR of 50–250 °C/min. • High osmolality extender (non-permeant solutes) inhibited chicken sperm motility. • Physiological osmolality allowed four days cold storage of diluted chicken semen. • DMA may be suitable alternative to glycerol for freezing chicken semen in straws. • Best post-thaw in vitro sperm quality using cooling rates 50–250 °C/min. • Best post-thaw in vitro sperm quality using DMA concentrations of 0.6–1.0 mol/l. [ABSTRACT FROM AUTHOR]

The mechanical recycling method of the carbon fiber-reinforced polymer (CFRP) has the advantages of simple process, less pollution and low cost, but only low utilization value of carbon fibers in powder or short fibers form can be obtained. To reduce the length and strength loss of the recycled carbon fibers, a novel and cost-effective dimethylacetamide (DMAC) swelling technique was developed to achieve rapid delamination of the CFRP laminates under mild conditions (120°C–160°C, 1 h). The corresponding swelling ratios and mass-loss rates of cured epoxy resin (CEP) were about 121.39%–157.39% and 0–0.69%, respectively. Excessive swelling of CEP in DMAC resulted in the cracking of the resin matrix between the adjacent carbon fiber layers. Thus the CFRP laminates were delaminated into soft single carbon fiber layers, which showed excellent cutting performance and reinforcing properties. The delamination products were cut into thin strips of different sizes and vacuum bag molded into new CFRP laminates. The flexural strength and tensile strength of the newly produced CFRP laminates were about 76.38%–90.98% and 94.61%–98.54% of the original CFRP laminates, respectively. More importantly, the chemical compositions of DMAC and CEP were unchanged during the physical swelling process. No organic pollutants (caused by resin degradation) were generated. And the used DMAC can be easily recycled by filtration. Therefore, this study provides a strategy for low-cost and high-valued recycling of CFRP waste.

The aim of this study was to compare the effect of two permeant-cryoprotectants, dimethylacetamide (DMA) and N-methylacetamide (NMA) used at different concentrations (0%, 2%, 4%, 6%) on the quality and fertility of post-thaw rooster semen. Ejaculates were processed in 7 treatments: Lake pre-freezing+0.1 M trehalose (LPF-T) (control treatment), LPF-T+2% DMA, LPF-T+4% DMA, LPF-T+6% DMA, LPF-T+2% NMA, LPF-T+4% NMA, LPF-T+6% NMA. Sperm quality [sperm membrane integrity (SMI), motility and kinetic parameters] was assessed before and after cryopreservation. Fertility and embryo viability were recorded. Increasing both DMA and NMA concentration from 2 to 6% improved SMI, total motile sperm, progressive motile sperm (PMS), VCL, VSL and VAP values. PMS recovery rates were significantly the highest in 6% DMA, 4% NMA and 6% NMA treatments. Semen cryopreserved with DMA produced the best fertility and embryo viability at 6%; progressive lower values were recorded at lower concentrations, with no viable embryos at 2%. Semen cryopreserved with NMA showed the best fertility values at 2% and lower values were recorded at higher concentrations; live embryos were found in all NMA treatments. Finally, NMA and DMA showed a similar positive concentration dependent effect of the quality of cryopreserved semen. NMA, not DMA, provided the highest fertility and embryo viability values at the lowest 2%. Therefore, the use of NMA is recommended in order to reduce the cryoprotectant concentration, with a concomitant reduction in the risk of toxicity, providing at the same time the adequate cryoprotective action to obtain viable embryos after artificial insemination of cryopreserved chicken semen. • Lower cryoprotectant concentrations in chicken sperm cryopreservation. • Evaluation of chicken sperm motility parameters. • Dimethylacetamide and N-methylacetamide in freezing poultry semen. • N-methylacetamide in synergy with Trehalose in frozen chicken sperm. • Live embryos obtained using rooster semen cryopreserved with N-methylacetamide. [ABSTRACT FROM AUTHOR]

Sperm cryopreservation is an effective technique for conserving animal genetic diversity and transmitting superior genetic backgrounds, maintained via a non-invasive sampling and collection of huge quantities of sperm. Nevertheless, cryopreservation in avian species is not commercially viable because of the rooster sperm’s susceptibility to damage. This study aims to estimate the impact of dimethylacetamide (DMA) as a cryoprotectant at different levels (3%, 6%, or 9%) on the post-thawed sperm quality, motility, antioxidant-biomarkers, and the expression of anti-freeze related genes. Semen samples were collected twice a week from twelve roosters aged 40 wk, weighing 3400 ± 70 g, and belonging to the Cairo-B2 chicken strain. Fresh semen samples were rapidly appraised, pooled, diluted with two volumes of a basic extender, and divided equally into three groups. The diluted groups were chilled at −20 °C for 7 min, then gently supplemented with 3, 6, or 9% pre-cooled DMA and equilibrated at 5 °C for a further 10 min. Semen pellets were formed by pipetting drops 7 cm above liquid nitrogen (LN2), which were then kept inside cryovials in the LN2. Thawing was performed 2 months later by taking 3–4 pellets of the frozen semen into a glass tube and warming it in a water bath for 8 s at 60 °C. The results showed that 3% DMA increased the proportion of total motile sperm, progressivity, viability, and plasma membrane integrity (%) compared to the 6% and 9% DMA groups. The lipid peroxidation and antioxidant enzyme activity were improved in the 3% group. At the same time, some anti-freeze-related genes’ (including ras homolog family member A (RHOA), heat shock protein 70 (HSP70), and small nuclear ribonucleoprotein polypeptide A (SNRPA1)) expressions were upregulated within the 3% DMA group relative to other groups. In conclusion, the 3% DMA group maintained higher post-thawed sperm quality than the other tested groups.

Wastewater from factories producing polysulfone-based membranes mainly contains the used organic solvent, i.e., dimethylacetamide (DMAc). Due to the environmental impact of DMAc, wastewater treatment is mandatory. Several biological treatment options based on the activated sludge process are described in the literature. Due to artificial aeration, these techniques have high energy requirements. Near-nature processes such as vertical flow constructed wetlands (VF wetlands) have a low energy demand, high tolerance to load fluctuations, and low maintenance requirements. Therefore, high-loaded, two-stage VF wetlands are an efficient option for treating wastewater. However, constructed wetlands have so far only been used to a limited extent for the treatment of industrial wastewater. In the present study, the ability of laboratory-scale, high-load, two-stage VF wetlands to treat DMAc was investigated. This included their DMAc degradation efficiency and corresponding pathways, removal of the total organic carbon (TOC), nitrification and denitrification of the nitrogen, as well as the ecotoxicological effects (mutagenicity, genotoxicity, reactive oxygen species) of untreated and treated wastewater. The focus was to determine the effect of different grain size distributions on removal rates, the maximum inflow loading, and the effect of high inflow concentrations on effluent concentrations. In general, DMAc was completely degraded using VF wetlands, with dimethylamine (DMA) identified as the main intermediate. TOC removal rates reached more than 99%. The nitrogen bound to DMAc was completely nitrified. However, the start-up of the VF wetlands without seeded filter material temporarily leads to high nitrite accumulation. This may affect the mutagenicity of the treated wastewater. The results show that high-loaded, two-stage VF wetlands are an effective option for treating wastewater containing DMAc with higher efficiency than comparable biological processes.

The alkyl and aryl derivatives of aniline are important starting materials in fine organic synthesis. Allyl bromide and benzyl chloride were taken as substrates for the alkylation reaction and as a halide ion scavenger. Triethylamine was utilized at reflux condition of N,N-dimethylacetamide (DMA). Novel synthesized N-benzyl and N-allyl aniline derivatives (1a-f) were evaluated to be highly potent inhibitors for acetylcholinesterase (AChE) and carbonic anhydrases (hCAs). The half maximal inhibitory concentration (IC50) of N-benzyl- and N-allyl aniline derivatives were calculated between 243.11 and 633.54 nM for hCA I, 296.32–518.37 nM for hCA II and 182.45–520.21 nM for AChE enzymes. On the other hand, Ki values are in the range of 149.24 ± 15.59 to 519.59 ± 102.27 nM for AChE, 202.12 ± 16.21 to 635.31 ± 45.33 nM for hCA I and 298.57 ± 94.13 to 511.18 ± 115.98 nM for hCA II isoenzyme. Additionally, in silico molecular docking computations were performed with Autodock Vina program to support the experimental in vitro studies for both hCAs and AChE inhibitors. The in silico molecular docking results demonstrated that the scores are in good agreement with the experimental results.

Objective: This study examines the association between 8-h time weighted N, N-dimethylacetamide (DMAc) air exposure and potential hepatocellular injury in a retrospective study among fibre-production workers in four European factories. Methods and Results: Twenty-nine (1.5%) of 1844 alanine aminotransferase (ALT) observations had liver values two times above normal; 0.2% three times above normal and 0.05% five times above normal. Two (0.1%) observations were indicative of hepatocellular injury. Logistic regression analyses showed an odds ratio for elevated ALT of 0.88 per 1 ppm (P trend = 0.39). Linear random effects regression analyses showed a decrease of one international unit (IU/L) ALT per 1 ppm increase of DMAc exposure (P  = 0.002). Conclusions: This study found no association between DMAc exposure and hepatoxicity amongst European workers. The prevalence of elevated liver values was lower compared to the general population without occupational exposure. [ABSTRACT FROM AUTHOR]

What Is Already Known About This Topic?: Dimethylacetamide (DMA), a colorless liquid with low toxicity, is commonly used as a solvent in the production of synthetic materials, petroleum processing, and pharmaceutical manufacture. In comparison to substances of higher toxicity, occupational exposure to DMA presents a deceptive risk due to its insidious and subacute progression, increasing the likelihood of escalating into major incidents., What Is Added by This Report?: In August 2023, an incident of occupational DMA poisoning involving six cases was reported at a spandex manufacturing factory in Zhuhai City, Guangdong Province, China, following post-fire management activities. All affected individuals were employees of an equipment maintenance company tasked with cleaning polymerizers. With the coordinated efforts of the health institutions in Guangdong Health Emergency Response Network for Poisoning Emergencies ( HERNPE ), the situation was promptly identified and addressed., What Are the Implications for Public Health Practice?: HERNPE serves as an effective framework for enhancing the integration of health institutions across various levels, facilitating a coordinated response that combines clinical services with public health initiatives. By leveraging the leadership of national centers, HERNPE plays a crucial role in the early detection, prevention, and management of large-scale health events., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)

Sperm cryopreservation is of great importance for the poultry industry but still needs to be optimized. The high susceptibility of poultry sperm to cryodamage leads to low fertility rates after cryopreservation. Therefore, the present study aimed at evaluating the effect of including a cryoprotectant, dimethylacetamide (DMA), in the chicken semen freezing extenders at a final concentration of 3%, 6%, or 9% on the post-thawed sperm motility, quality, antioxidant biomarkers, anti-freeze gene expression, and fertilizing ability. Results showed that the total motile sperm, progressivity, and viability were quadratically increased (p < 0.05) in the 6% DMA group. The antioxidant enzyme activity and lipid peroxidation were negatively (p < 0.05) affected by the increase in DMA concentration. Furthermore, some anti-freeze-associated genes such as heat shock protein 70 (HSP70) and ras homolog family member A (RHOA) were linearly and quadratically down-regulated (p < 0.05) with the high concentration of DMA. Finally, the fertility and hatchability rates did not indicate statistical differences between DMA groups. It can be concluded that using the low concentration of 3–6% DMA in the freezing semen extender is preferable to obtain acceptable results in the post-thawed sperm quality and fertility.

ABSTRACT: Chicken semen cryopreservation is a tool for programs of genetic diversity management and endangered breeds conservation. Due to physiological features, the fertility rates of cryopreserved poultry sperm are lower than mammal species. Thus, improvement of the semen cryopreservation methods is required. A first study was performed by a 2 × 2 factorial design consisting of 2 methods of adding the cryoprotectant [Direct or Diluted (mixed with extender medium)] and 2 cryoprotectants (glycerol and dimethylacetamide). Then sperm quality indicators were evaluated after freezing. A second study with a 2 × 2 design was conducted to evaluate the effectiveness of bovine serum albumin (BSA) on the optimization of 2 different extenders (Lake and Animal Sciences Group [ASG]). Viability and motility variables were evaluated before and after freezing. There was no significant difference in sperm viability and motility variables between Direct or Diluted methods. Supplementation of extenders with BSA improved most of the sperm motility variables in both extenders before and after freezing. Progressive sperm, non-progressive sperm before freezing, and all post-thaw sperm motility parameters, except amplitude of lateral head displacement and beat-cross frequency, were increased in BSA-supplemented extenders (P < 0.05), and BSA improved sperm viability in ASG extender after thawing (P < 0.05). After thawing, the interaction between extender and BSA (P < 0.05), eliminated the differences between the 2 BSA-supplemented media in curvilinear velocity, straight-line velocity, average path velocity, and amplitude of lateral head displacement which were higher in non-supplemented ASG extender than nonsupplemented Lake medium. In conclusion, the direct or diluted methods of adding glycerol or dimethylacetamide, did not significantly affect the post-thaw sperm characteristics. BSA positively affected most of the post-thaw sperm motility indicators regardless of the type of extender and resulted in significantly higher post-thaw sperm viability in ASG medium.

We report here the viscosity blending approach toward high efficiency perovskite solar cells. A binary solvent is introduced in the precursor solution, where 2‐methoxyethaol (2ME) is mixed with dimethylformamide (DMF) or dimethylacetamide (DMAc). Viscosity of the binary solvent system is estimated by calculating the viscosity blending number. For the ratio of DMF (DMAc): 2ME = 75:25 leading to the viscosity of 1.0317 (1.1699) cSt, a forward‐scanned power conversion efficiency (PCE) of 22.42% is achieved along with photocurrent density of 25.46 mA/cm2, voltage of 1.122 V and fill factor of 0.785, which is higher than the PCE of 20.59% for the single DMF solvent. The binary solvent with optimal viscosity is found to be beneficial to reducing trap density and improving carrier lifetime even in thicker perovskite film. [ABSTRACT FROM AUTHOR]

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Copyright of Problems of Cryobiology & Cryomedicine / Problemy Kriobiologii i Kriomediciny is the property of National Academy of Sciences of Ukraine Institute for Problems of Cryobiology & Cryomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study synthesized water-based polyurethane with acrylate terminal group (WPUA) using the long carbon chain of stearyl acrylate to synthesize hydrophobic poly-stearyl acrylate (PSA). The proposed process could minimize environmental pollution caused by fluorine-containing monomers. As a water-based polyurethane (WPU) end-capping agent, the hydrophobic PSA and the hydrophilic and water vapor permeable WPU are copolymerized to form a WPUA functional resin with simultaneous water vapor permeability (WVP) and water repellency. Here, 2-mercaptoethanol was used to control the molecular weight of PSA to prepare the acrylate end-capping agent. PSA was then employed in WPU to form WPUA, which is characterized by the moisture permeability of WPU and water repellency of acrylic resin simultaneously. During the WPUA process, dimethylacetamide was used as a neutralizer to replace the traditional toxic chemical control drug triethylamine. This study set up the material and chemical structure to replace the toxic chemical-controlled drugs and organofluoride in the traditional preparation of moisture permeable and water repellent materials. The proposed process was proven to reduce the consumption of organic solvent, achieve WPUA copolymer stability, and provided moisture permeable and water repellent functions. In addition, Fourier transform infrared spectroscopy was used to determine the structure of WPUA, while thermogravimetry analysis and differential scanning calorimetry were performed to establish the thermal properties of WPUA. After the WPUA was padded on nylon fabric, its water drop contact angle was observed through a scanning electron microscope. The results showed that the contact angle of nylon fabric increased significantly, water repellency was reached, and WVP rises by 23.75%. [ABSTRACT FROM AUTHOR]

Sperm cryopreservation is a tool for the conservation of the genetic material of animals of genetic importance or for species preservation. In the case of domestic cats, this can be used to generate information about seminal harvest, evaluation and preservation, which is especially important due to its applicability to wild felids. This study evaluated seminal samples harvested by urethral catheterisation from 13 adult domestic cats. Samples were cryopreserved with experimental groups of extenders were defined by the penetrating cryoprotectant: 6% glycerol (GLY6%), 3% dimethylacetamide (DMA3%) and 3% dimethylformamide (DMF3%). The samples were thawed and evaluated by conventional microscopy and by computer-assisted sperm analysis (CASA). The structural and functional membrane integrity was assessed by supravital tests (EOS), hypoosmotic swelling tests (HOST) and flow cytometry (FC). There was a correlation (P < 0.05) between total motility and EOS (r = 0.54), HOST and FC (r = −0.62) and total motility and flow cytometry (r = 0.63), indicating that these are complementary parameters that increase the accuracy of the feline sperm quality evaluation post-thaw. The results regarding the structural and functional integrity of the sperm plasma membrane did not differ (P > 0.05) among groups. However, the DMA3% group had a lower (P < 0.05) percentage of morphological changes in the sperm tail compared to samples cryopreserved with GLY6% and DMF3%. Additionally, DMA3% provided lower values of immobile sperm post-thaw when compared to DMF3%. DMA is an interesting alternative to GLY and superior to DMF for the cryopreservation of feline semen at the studied concentrations. Image 1 • Semen collection by catheterisation, after asministration with Alpha agonist is an efficient technique in domestic cats. • Dimethylacetamide demostrates greater protection against sperm tail injuries in cats, than glycerol and dimethylformamide. • Dimethylacetamide is an alternative cryoprotectant to glycerol and superior than dimethylformamide, for domestic cats. [ABSTRACT FROM AUTHOR]

A method for separating sodium alginate through polysulfone (PSf) support by dimethyl acetamide (DMAc) and hydraulic treatment was studied. After exposing the PSf support to DMAc solvent, water pressure was applied onto the polymer support. As a result, the sponge-type structures were connected to each other and the porosity of the modified PSf increased. In addition, the support pressurized for 3 minutes at 8 bar had the highest value of 133 L/m2h and removal rate of 95.0% for sodium alginate filtration test. When the PSf support was immersed in an organic solvent, the interaction between the chains of the PSf was weakened, while when water pressure was applied, pores were generated. These results were confirmed by SEM, FT-IR and porosimeter data. [ABSTRACT FROM AUTHOR]

The presence of dimethylacetamide (DMAA) in the composition of electrolytes of a sodium-ion battery destroys the passive film on electrodes and results in a number of reactions not connected with the electrochemical process that must be considered in developing such batteries. Introducing DMAA into the composition of a battery electrolyte greatly improves the conductivity of the polymeric membrane that separates the cathode and anode spaces. However, it is established that in the presence of sodium metal, anhydrous DMAA undergoes Claisen-like self-condensation with subsequent reactions. IR spectroscopy is used to explain the causes of the electrochemical instability of sodium perchlorate solutions in mixed solvents containing DMAA. [ABSTRACT FROM AUTHOR]

Ultrasonic velocity and density for monomethylammonium perchlorate (CH3NH3ClO4) in non-aqueous solvents Dimethylsulfoxide (DMSO), N, N-Dimethylacetamide (DMA) and Acetonitrile (AN) were measured as a function of molality at temperatures 298K, 308K, 318K and 328K using DSA 5000M (Anton Paar density and sound velocity meter). Using this data, various acoustical parameters like adiabatic compressibility (Ks), apparent molal volume (VF), specific acoustic impedance (Z), intermolecular free lengths (Lf) and relative association (RA) have been determined. The variation of the acoustical parameters studied with molal concentration is then explored to understand the fundamental picture of various intermolecular interactions taking place. [ABSTRACT FROM AUTHOR]

Hydration in aqueous solutions of dimethylacetamide was studied by IR spectroscopy and quantum chemistry; the concentration and structural zones were determined. An analysis of the concentration dependences of IR absorption of these solutions at different frequencies showed that heteroassociates with stoichiometric ratios of components of 2 : 1, 1 : 1, 1 : 2, and 1 : 4 formed in them in sequence. The composition, structure, formation energy, and relative stability of the heteroassociates were determined from the results of DFT calculations for 19 hydrates. The stability of dimethylacetamide hydrates was shown to increase with the relative content of water molecules in them. [ABSTRACT FROM AUTHOR]

The liquid structure of the commonly used solvents dimethylformamide (DMF) and dimethylacetamide (DMA)were measured using state-of-the-art state neutron diffraction augmented with isotopic substitution (NDIS) and interpreted with empirical potential structure refinement (EPSR). Both solvents are found to develop rich local ordering with similar local packing densities, though with differences related to their three-dimensional molecular structure. While DMF's dipole preferentially orientates anti-parallel to maximise hydrogen bonding, DMA favours parallel arrangement maximising non-directional dispersive forces. The highly-developed local orientational structure found in these solvents rationalises their ability to solvate a range of charged and neutral nanomaterials and highlights that the understanding of nanomaterial dispersions is a multi-body problem in which the geometry of the molecule, as well its dipole moment, must be incorporated. [ABSTRACT FROM AUTHOR]

Abstract A new dyeing mechanism based on macro-cation was proposed. To confirm this mechanism, the dyeing effect of the concentration of hydrogen bonding regulator, dimethylacetamide (DMAc), on the dyeing effect of poly- m -phenyleneisophthalamide (MPIA) fibers with cationic dyes was compared with that using neutral dyes. DMAc and NaCl can synergistically and selectively break the inter-molecular hydrogen bonds of MPIA. The color characteristics of dyed fabrics were measured and analyzed. The color depth of fabric dyed using cationic dye increases with increased DMAc and NaCl concentrations. Cationic dyes and DMAc form macro-cations, [DMAc-Dye]+, which facilitates the adsorption and subsequent fixing of dyes with MPIA fibers. And optimal dyeing effect shows two times of K/S value with cationic dyes than that with neutral dyes. More importantly, there is no deterioration in both the mechanical properties and thermal stability of the fabrics after dyeing. These findings can serve as a mechanistic guide for the selection of dyes for MPIA fibers. Highlights • Dyeing mechanism based on macro-cation. • Dimethylacetamide (DMAc) used as hydrogen bonding regulator for aramid. • DMAc-NaCl system can help cationic dyes achieve excellent dyeing effect. • Mechanical properties and thermal stability of dyed fibers were not affected. [ABSTRACT FROM AUTHOR]

The treatment of aryl amines with dimethylformamide (DMF) and dimethylacetamide (DMA) in the presence of hydrochloric acid brings about efficient N-acylation to give the corresponding aryl formamides and aryl acetamides in acceptable to excellent yields. This method is simple, general, and practical for the rapid construction of aryl formamide and aryl acetamide derivatives.

Rhodium(I)-complex [Rh(CO)2I2−] (1) catalyzed two carbonylations of methyl iodide and trimethylamine in NMP (1-methyl-2-pyrolidone) to acetic acid and DMAC (N,N-dimethylacetamide) in the presence of calcium oxide and water. The carbonylation of trimethylamine continued during the carbonylation and consumption of methyl iodide. In total, 183.8 mmol of carbonylated products was produced while consuming 24.1 mmol methyl iodide via acetic acid formation. These results clearly indicated that there were two carbonylation routes of trimethylamine and methyl iodide and the carbonylation rate of trimethylamine was faster than that of methyl iodide. Rhodium(I)-complex [Rh(CO)2I2]− (1) in the presence of trimethylamine was stable enough to be used 25 times with TON (Turnover Number) of 368 for DMAC and TON of 728 for trimethylamine. Inner-sphere reductive elimination in stepwise procedure was suggested for the formation of DMAC instead of acyl iodide intermediate under anhydrous condition.

Quasi-solid bioelectrolytes based on hydroxyethyl cellulose (HEC) and sodium iodide (NaI) in three different polar aprotic solvent systems, dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and dimethylacetamide (DMA), were fabricated and characterized. FTIR studies revealed active solvent-ion interactions in DMF-based electrolytes in comparison to DMA and DMSO. The effect of the solvent system on the crystallinity of HEC gel electrolytes was more significant at low NaI concentration. In each solvent system, the highest ionic conductivity was achieved at 70 wt% NaI and generally DMF-based electrolytes showed higher conductivity than the other solvents. The availability of multiple complexation sites present in DMF is ascribed to improvement in ion mobility and hence conductivity. Rheological analysis was carried out to elucidate the mechanical properties of the gels. Generally, the mechanical strength of the polymer gels was unaffected by the type of solvent. [ABSTRACT FROM AUTHOR]

Abstract: Dimethylformamide and dimethylacetamide are important industrial chemicals, which are used, e.g., as solvents in the manufacturing of polyurethane products. They are conventionally recovered by distillation associated with high energy consumption and operating costs. In contrast, pervaporation is an energy‐efficient membrane separation method. Ceramic‐supported copolyimide membranes were synthesized via the two‐step thermal imidization method and applied to pervaporation recovery of dimethylformamide and dimethylacetamide. The prepared membrane demonstrated high resistance to the two amides in a wide concentration range. Effects of operating parameters such as feed temperature and feed concentration on pervaporation performances were investigated. The results showed that the copolyimide membrane is a promising candidate for the recovery of high concentrations of amide solvents. [ABSTRACT FROM AUTHOR]

In order to increase environmental and economic benefits of waste Random Access Memory (RAM) recycling, this research aims to separate all metallic and non-metallic components of RAM by using chemical treatment and subsequent leaching process to liberate gold from gold-plated components. Chemical treatment was employed to separate metal (copper foils, contacts, through-hole pads) from non-metal by performing organic solvent Dimethylacetamide (DMA) and ultrasonic treatment at a low temperature (50 °C) in order to dissolve Brominated Epoxy Resin (BER) and separate all layers of waste RAMs. The process was carried out in a simple reactor developed specifically for this purpose. After the dissolution process, a rotary decompression evaporator was used to extract epoxy resin from DMA/BER solution and regenerate the solvent. At the same time, leaching by nitric acid was used to liberate gold from parts with high gold concentration, in particular from contacts. SEM-EDS, TGA, DSC, FTIR, and UV-VIS spectroscopy were used to characterize the recovered epoxy resin, metal, and regenerated DMA. Additionally, metallographic microscope was used to examine the DMA/BER solution. The results showed that RAMs were composed of seven layers of plain woven fiberglass, four copper foil layers, conductive tracks, contacts, solder joints of integrated circuits, epoxy resin, and soldermask. Moreover, gold with purity >94% was successfully recovered as a result of applying developed treatment technique with yield ∼12 times higher than traditional milling followed by leaching approach. [ABSTRACT FROM AUTHOR]

The paper presents the results of tests of an electromembrane installation for the complex processing of a technological solution formed in the production of para-aramid fibers. The installation consists of two main units and three different electrodialysers, each of which performs its specific function. Electrodialysis with bipolar membranes is designed to produce lithium hydroxide, a conventional electrodialysis module is designed for preliminary treatment of the technological solution and its preconcentration and electrodialysis with ion-exchange resin serves for finishing cleaning and complete removal of ionic impurities from the solution. Optimum parameters of the process were chosen, which allows processing 6.3 m 3 of technological solution per day. The total operating time of the installation during the tests was 770 h. The main specific characteristics of the process of obtaining lithium hydroxide by electrodialysis with bipolar membranes from technological solutions with a mass fraction of organic components ranging from 1.8 to 59% are determined. The average current efficiency in solutions with different contents of organic components were 0.6; the specific productivity for lithium hydroxide decreases from 5.7 to 2.1 mol × m −2 × h −1 with an increase in the proportion of organic solvents. The combination of conventional and ion-exchange electrodialysis allows obtaining a pure water-organic mixture with a current yield of no less than 0.4. During the entire operation of the plant, no signs of degradation of the ion-exchange membranes used and deterioration of the installation operation have been detected. [ABSTRACT FROM AUTHOR]