Identification of 3-Aryl-1-benzotriazole-1-yl-acrylonitrile as a Microtubule-Targeting Agent (MTA) in Solid Tumors.

Recently, a compound derived from recent scientific advances named 34 has emerged as the focus of this research, the aim of which is to explore its potential impact on solid tumor cell lines. Using a combination of bioinformatics and biological assays, this study conducted an in-depth investigation of the effects of 34. The results of this study have substantial implications for cancer research and treatment. 34 has shown remarkable efficacy in inhibiting the growth of several cancer cell lines, including those representing prostate carcinoma (PC3) and cervical carcinoma (HeLa). The high sensitivity of these cells, indicated by low IC50 values, underscores its potential as a promising chemotherapeutic agent. In addition, 34 has revealed the ability to induce cell cycle arrest, particularly in the G2/M phase, a phenomenon with critical implications for tumor initiation and growth. By interfering with DNA replication in cancer cells, 34 has shown the capacity to trigger cell death, offering a new avenue for cancer treatment. In addition, computational analyses have identified key genes affected by 34 treatment, suggesting potential therapeutic targets. These genes are involved in critical biological processes, including cell cycle regulation, DNA replication and microtubule dynamics, all of which are central to cancer development and progression. In conclusion, this study highlights the different mechanisms of 34 that inhibit cancer cell growth and alter the cell cycle. These promising results suggest the potential for more effective and less toxic anticancer therapies. Further in vivo validation and exploration of combination therapies are critical to improve cancer treatment outcomes.

Estimating impacts of reducing acrylonitrile exposure on lung cancer mortality in an occupational cohort with the parametric g-formula.

OBJECTIVES: To inform the potential human carcinogenicity of acrylonitrile, we estimate associations between acrylonitrile exposures and lung cancer mortality in US workers with the objectives of (1) assessing potential for healthy worker survivor bias and (2) adjusting for this bias while assessing the expected lung cancer mortality under different hypothetical occupational exposure limits on acrylonitrile exposure using the parametric g-formula. METHODS: We used data from a cohort of 25 460 workers at facilities making or using acrylonitrile in the USA. We estimated HRs to quantify associations between employment and lung cancer mortality, and exposure and leaving employment. Using the parametric g-formula, we estimated cumulative lung cancer mortality at hypothetical limits on acrylonitrile exposure. RESULTS: Recent and current employment was associated with lung cancer, and exposure was associated with leaving employment, indicating potential for healthy worker survivor bias. Relative to no intervention, reducing the historical exposure under limits of 2.0, 1.0 and 0.45 parts per million would have been expected to reduce lung cancer mortality by age 90 by 4.46 (95% CI 0.78 to 8.15), 5.03 (95% CI 0.96 to 9.11) and 6.45 (95% CI 2.35 to 10.58) deaths per 1000 workers, respectively. A larger lung cancer mortality reduction would be expected under elimination of exposure: 7.21 (95% CI 2.72 to 11.70) deaths per 1000 workers. CONCLUSIONS: Healthy worker survivor bias likely led to underestimation of excess risk. Our results corroborate previous study findings of an excess hazard of lung cancer among the highest exposed workers.

Biological activity and computational analysis of novel acrylonitrile derived benzazoles as potent antiproliferative agents for pancreatic adenocarcinoma with antioxidative properties.

Continuing our research into the anticancer properties of acrylonitriles, we present a study involving the design, synthesis, computational analysis, and biological assessment of novel acrylonitriles derived from methoxy, hydroxy, and N-substituted benzazole. Our aim was to examine how varying the number of methoxy and hydroxy groups, as well as the N-substituents on the benzimidazole core, influences their biological activity. The newly synthesized acrylonitriles exhibited strong and selective antiproliferative effects against the Capan-1 pancreatic adenocarcinoma cell line, with IC50 values ranging from 1.2 to 5.3 µM. Consequently, these compounds were further evaluated in three other pancreatic adenocarcinoma cell lines, while their impact on normal PBMC cells was also investigated to determine selectivity. Among these compounds, the monohydroxy-substituted benzimidazole derivative 27 emerged with the most profound and broad-spectrum anticancer antiproliferative activity being emerged as a promising lead candidate. Moreover, a majority of the acrylonitriles in this series exhibited significant antioxidative activity, surpassing that of the reference molecule BHT, as demonstrated by the FRAP assay (ranging from 3200 to 5235 mmolFe2+/mmolC). Computational analysis highlighted the prevalence of electron ionization in conferring antioxidant properties, with computed ionization energies correlating well with observed activities.

Novel acrylonitrile derived imidazo[4,5-b]pyridines as antioxidants and potent antiproliferative agents for pancreatic adenocarcinoma.

We present the design, synthesis, computational analysis, and biological assessment of several acrylonitrile derived imidazo[4,5-b]pyridines, which were evaluated for their anticancer and antioxidant properties. Our aim was to explore how the number of hydroxy groups and the nature of nitrogen substituents influence their biological activity. The prepared derivatives exhibited robust and selective antiproliferative effects against several pancreatic adenocarcinoma cells, most markedly targeting Capan-1 cells (IC50 1.2-5.3 µM), while their selectivity was probed relative to normal PBMC cells. Notably, compound 55, featuring dihydroxy and bromo substituents, emerged as a promising lead molecule. It displayed the most prominent antiproliferative activity without any adverse impact on the viability of normal cells. Furthermore, the majority of studied derivatives also exhibited significant antioxidative activity within the FRAP assay, even surpassing the reference molecule BHT. Computational analysis rationalized the results by highlighting the dominance of the electron ionization for the antioxidant features with the trend in the computed ionization energies well matching the observed activities. Still, in trihydroxy derivatives, their ability to release hydrogen atoms and form a stable O-H⋯O•⋯H-O fragment upon the H• abstraction prevails, promoting them as excellent antioxidants in DPPH• assays as well.

Extraction of volatile organic compounds liberated upon filament extrusion by 3D pen and its comparison with a desktop 3D printer using solid-phase microextraction fiber and Arrow.

Desktop 3D printers that operate by the fused deposition modeling (FDM) mechanism are known to release numerous hazardous volatile organic compounds (VOCs) during printing, including some with potential carcinogenic effects. Operating in a similar manner to FDM 3D printers, 3D pens have gained popularity recently from their ability to allow users to effortlessly draw in the air or create various 3D printed shapes while handling the device like a pen. In contrast to numerous modern 3D printers, 3D pens lack their own ventilation systems and are often used in settings with minimum airflow. Their operation makes users more vulnerable to VOC emissions, as the released VOCs are likely to be in the breathing zone. Consequently, monitoring VOCs released during the use of 3D pens is crucial. In this study, VOCs liberated while extruding acrylonitrile butadiene styrene (ABS) filaments from a 3D pen were measured by solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS). SPME was investigated using the traditional fiber and Arrow geometries with the DVB/Carbon WR/PDMS sorbent while four different brands of ABS filaments-Amazon Basics, Gizmodork, Mynt 3D, and Novamaker-were used with the 3D pen. Heatmap analysis showed differentiation among these brands based on the liberated VOCs. The nozzle temperature and printing speed were found to affect the number and amount of released VOCs. This study goes a step further and presents for the first time a comparison between 3D pen and a desktop 3D printer based on liberated VOCs. Interestingly, the findings reveal that the 3D pen releases a greater number and amount of VOCs compared to the printer. The amounts of liberated VOCs, as indicated by the corresponding chromatographic peak areas, were found to be 1.4 to 62.6 times higher for the 3D pen compared to the 3D printer when using SPME Arrow.

Perioperative exposure to volatile organic compounds in neonates undergoing cardiac surgery.

OBJECTIVE: Volatile organic compounds (VOCs) are used in the sterilization and manufacture of medical equipment. These compounds have high vapor pressures with low water solubility and are emitted as gases from solids or liquids. They can be mutagenic, neurotoxic, genotoxic, and/or carcinogenic. Safe limits of exposure are not known for neonates. This study examined determinants of exposure in newborns undergoing cardiac surgery. METHODS: Twenty metabolites of 16 VOCs (eg, xylene, cyanide, acrolein, acrylonitrile, N, N-dimethylformamide, 1,3-butadiene, styrene, and benzene) were measured as metabolites in daily urine samples collected from 10 neonates undergoing cardiac operations (n = 150 samples). Metabolites were quantified using reversed-phase ultra-high performance liquid chromatography and electrospray ionization tandem mass spectrometry. Repeated measures analysis of covariance was performed for each metabolite to examine associations with use of medical devices. RESULTS: At least 3 metabolites were detected in every sample. The median number of metabolites detected in each sample was 14 (range, 3-15). In a model controlling for other factors, the use of extracorporeal membrane oxygenation was associated with significantly (P ≤ .05) greater metabolite levels of acrolein, acrylonitrile, ethylene oxide, propylene oxide, styrene, and ethylbenzene. Patients breathing ambient air had greater levels of metabolites of acrolein, xylene, N,N-dimethylformamide, methyl isocyanate, cyanide, 1,3-butadiene (all P ≤ .05). CONCLUSIONS: Exposure to volatile organic compounds is pervasive in newborns undergoing cardiac surgery. Sources of exposure likely include medical devices and inhalation from the air in the intensive care unit. The contribution of VOC exposure during cardiac surgery in newborns to adverse outcomes warrants further evaluation.

Novel 3-(pyrazol-4-yl)-2-(1H-indole-3-carbonyl)acrylonitrile derivatives induce intrinsic and extrinsic apoptotic death mediated P53 in HCT116 colon carcinoma.

A novel series of α-cyano indolylchalcones was prepared, and their chemical structures were confirmed based on the different spectral data. Among them, compound 7f was observed to be the most effective bioactive chalcone with distinguished potency and selectivity against colorectal carcinoma (HCT116) with IC50 value (6.76 µg/mL) relative to the positive control (5 FU) (77.15 µg/mL). In a preliminary action study, the acrylonitrile chalcone 7f was found to enhance apoptotic action via different mechanisms like inhibition of some anti-apoptotic protein expression, regulation of some apoptotic proteins, production of caspases, and cell cycle arrest. All mechanisms suggested that compound 7f could act as a professional chemotherapeutic agent. Also, a molecular docking study was achieved on some selected proteins implicated in cancer (Caspase 9, XIAP, P53 mutant Y220C, and MDM2) which showed variable interactions with compound 7f with good Gibbs free energy scores.

Evaluation and modeling of acrylonitrile migration from polypropylene for food packaging.

This study validated an analytical technique using headspace gas chromatography with flame ionization detection to quantify acrylonitrile monomer with a quantification limit of 0.10 ± 0.04 µg kg-1 . Subsequently, the acrylonitrile migration from polypropylene granules was evaluated in food simulants water and ethanol (50% v/v) and at two temperatures (20 ± 1°C and 44 ± 2°C) for up to 6 weeks, representing the service time of a bottle. From the experimental data obtained, pseudo-second-order kinetics were adjusted to represent the acrylonitrile migration into the simulants. For water, equilibrium concentrations of 13.58 and 16.58 µg kg-1 at 20 and 44°C, respectively, were obtained, while for 50% ethanol, 15.07 and 16.40 µg kg-1 were obtained for the same temperatures. The experimental results and the values estimated from the migration kinetics indicate that the maximum acrylonitrile concentration will not exceed the tolerable specific limit established in regulations. PRACTICAL APPLICATION: The migration of compounds such as acrylonitrile can be a drawback resulting in an undesirable reduction in the shelf life of liquid foods packaged in bottles made of materials such as polypropylene. In this paper, acrylonitrile migration kinetics and a methodology are proposed to determine whether the tolerable migration limits are ever reached, which can serve as a tool for producers of this type of packaging of food to predict shelf life.

Chemometrics-based Discrimination of Virgin and Recycled Acrylonitrile-Butadiene-Styrene Plastics Toys via Non-targeted Screening of Volatile Substances.

Owing to the growing emphasis on child safety, it is greatly urgent to identify and assess the unknown compounds and discriminate the recycled materials for plastic toys. In this study, gas chromatography mass spectrometry coupled with static headspace has been optimized by response surface methodology for non-targeted screening of unknown volatiles in acrylonitrile-butadiene-styrene (ABS) plastic toys. Optimum conditions for static headspace were 120 °C for extraction temperature and 48 min for extraction time. A total of 83 volatiles in 11 categories were qualitatively identified by matching the NIST database library, retention index and standard materials. Considering high positive rate and potential toxicity, high-risk volatiles in ABS plastic toys were listed and traced for safety pre-warning. Moreover, the differential volatiles between virgin and recycled ABS plastics were screened out by orthogonal partial least-squares discrimination analysis. Principal component analysis, hierarchical cluster analysis and linear discrimination analysis were employed to successfully discriminate recycled ABS plastic toys based on the differential volatiles. The proposed strategy represents an effective and promising analytical method for non-targeted screening and risk assessment of unknown volatiles and discrimination of recycled materials combining with various chemometric techniques for children's plastic products to safeguard children's health.

Non-isothermal thermal decomposition behavior and reaction kinetics of acrylonitrile butadiene styrene (ABS).

Environmental concerns associated with the rapid rising plastic consumption have led to the search for better waste utilization and management. Pyrolysis has emerged as an ideal and promising technique for energy extraction from plastic waste. The aim of this work is to explore the waste plastic pyrolysis behavior under non-isothermal heating conditions. The decomposition characteristics, reaction mechanism, kinetics and thermodynamics of a typical widely used thermosetting plastic, acrylonitrile butadiene styrene (ABS), were studied via coupled thermogravimetry, Fourier transform infrared spectrometry and gas chromatography-mass spectrometry analysis (TG-FTIR-GC/MS). Kinetic analysis showed the average Eα values are estimated to be 187.02, 188.55, 187.04 and 185.67 kJ/mol via advanced Vyazovkin, Flynn-Wall-Ozawa (FWO), Tang and Starink model-free method, respectively. Model-fitting CR and master-plots method indicated that f(α)=(1-α)n is the most probable reaction mechanism. The equation of kinetic compensation effect was further developed as lnA = -3.1955 + 0.1736 Eα. Based on these initial inferences, a new reaction scheme coupled with Particle Swarm Optimization (PSO) was put forward for modeling ABS pyrolysis. The optimized values of E, A and n are 198.07 kJ/mol, 7.61 × 1012 s-1 and 1.56, respectively. The predicted results showed that the experimental data can be well characterized by the optimized parameters from PSO, validating the effectiveness and accuracy of the inverse modeling procedure. Moreover, it is found that the volatile products are mainly composed of aromatic compounds, ketones, amines, esters, nitrile compounds, alkenes and amines. Based on the FT-IR and GC-MS results, the possible chemical reactions for ABS pyrolysis from molecular structure were proposed. Finally, thermodynamic analysis was carried out, the calculated values of enthalpy ΔH, Gibb's free energy ΔG and entropy ΔS indicated that non-spontaneous reactions with low favorability exists during ABS decomposition, the process is complex therefore extra energy is needed to promote the reaction. The obtained results should offer as an important reference for future disposal and thermochemical management of such polymer waste.

Elicitation of E-waste (acrylonitrile-butadiene styrene) enriched soil bioremediation and detoxification using Priestia aryabhattai MGP1.

Given the rise in both usage and disposal of dangerous electronics, there is a catastrophic rise in assemblage of electronic waste (e-waste). E-waste including various plastic resins are among the most frequently discarded materials in electronic gadgets. In current digital era, managing e-waste has become universal concern. From the viewpoint of persisting lacuna of e-waste managing methods, the current study is designed to fabricate an eco-friendly e-waste treatment with native soil bacteria employing an enrichment culture method. In the presence of e-waste, indigenous soil microbes were stimulated to degrade e-waste. Microbial cultures were isolated using enrichment medium containing acrylonitrile-butadiene styrene (ABS) as the primary carbon source. Priestia aryabhattai MGP1 was found to be the most dominant e-polymer degrading bacterial isolate, as it was reported to degrade ABS plastic in disposed-off television casings. Furthermore, to increase degradation potential of MGP1, Response Surface Methodology (RSM) was adopted which resulted in optimized conditions (pH 7, shaking-speed 120 rpm, and temperature 30 °C), for maximum degradation (18.88%) after 2 months. The structural changes induced by microbial treatment were demonstrated by comparing the findings of Field emission scanning electron microscopy (FESEM) images and Fourier Transform Infrared (FTIR) spectra confirming the disappearance of ≡ C─H peaks along with C-H, C=C and C ≡N bond destabilization following degradation. Energy-dispersive X-ray (EDX) analyzers of the native and decomposed e-polymer samples revealed a considerable loss in elemental weight % of oxygen by 8.4% and silica by 0.5%. Magnesium, aluminium and chlorine which were previously present in the untreated sample, were also removed after treatment by the bacterial action. When seeds of Vigna radiata were screened using treated soil in the presence of both e-waste and the chosen potent bacterial strain, it was also discovered that there was reduced toxicity in terms of improved germination and growth metrics as a phytotoxicity criterion.

Development of cashew nut shell lignin-acrylonitrile butadiene styrene 3D printed core and industrial hemp/aluminized glass fiber epoxy biocomposite for morphing wing and unmanned aerial vehicle applications.

The aim of this study was to develop a lightweight epoxy based biocomposite for morphing wing and unmanned aerial vehicle (UAV) applications. The proposed composite was developed using a 3D printed high stiffness lignin-Acrylonitrile Butadiene Styrene (ABS) core and industrial hemp with aluminized glass fiber epoxy skin. The ABS was reinforced using lignin macromolecule derived from cashew nut shells via twin screw extruder and the core was printed using an industrial grade 3D printer. Furthermore, the composites were prepared by compression moulding with an ABS-lignin core and hemp/aluminized GF surface and characterized according to respective American society of testing and materials (ASTM) standards. The findings indicate that the addition of 30 vol% Al-glass and hemp fiber with lignin strengthened ABS core improved the mechanical properties. The composite material designated as "E2" exhibits the maximum mechanical properties, providing tensile strength, flexural strength, Izod impact, interlaminar shear strength (ILSS), and compression values of, 136 MPa, 168 MPa, 4.82 kJ/m2, 21 MPa, and 155 MPa respectively. The maximal energy absorbed by composite designation "E2," during drop load impact test is 20.6 J. Similarly, the composite designation "E2"gives fatigue life cycles of 33,709, 25,781 and 19,633 for 50 %, 70 % and 90 % of ultimate tensile strength (UTS) and 32.5 (K1c) MPa⋅m and 0.76 (G1c) MJ/m2 in fracture toughness and energy release rate respectively.

Experimental investigation of acrylonitrile butadiene styrene plastics plasma gasification.

E-waste comprising plastics causes serious ecological problems due to low degradability, but it is capable of producing a high amount of energy by thermochemical conversion. Therefore, the current study focuses on generating clean syngas through plasma gasification of acrylonitrile butadiene styrene (ABS) based computer keyboard plastic waste (CKPW) using CO2 as a gasifying agent. The effect of feed rate, gas flow rate and plasma power on the syngas composition was studied. In addition, a comprehensive investigation of energy, exergy, economic and environmental analyses along with characterization of the obtained products was conducted to evaluate the performance of the system. Based on the experimental results, the optimum process parameters for producing syngas possessing a higher calorific value (15.80 MJ/m3) with a higher percentage of H2 (30.16 vol%) and CO (46.09 vol%) were estimated. The optimum feed flow rates of solid fuel and CO2 gas and torch power were estimated as 40 g/10 min, 0.5 lpm and 1.12 kW, respectively. At these conditions, the system could achieve a maximum energy and exergy efficiency of 46.06% and 44.34%, respectively, while the levelized cost of syngas (LCOSover) was estimated as 25.45 INR/kWh, including the social cost. Likewise, the lower values of the estimated global warming potential (370.19 gCO2eq/h) illustrate the better sustainability of the process. The obtained oil with the estimated LHV of 39.13 MJ/kg could be an alternative fuel for diesel and the residue containing a higher proportion of TiO2 has medical applications upon further enrichment. The reaction mechanism of ABS conversion to syngas under plasma gasification conditions is proposed.

Acrylonitrile's genotoxicity profile: mutagenicity in search of an underlying molecular mechanism.

Acrylonitrile (ACN) is a known rodent and possible human carcinogen. There have also been concerns as to it causing adverse reproductive health effects. Numerous genotoxicity studies at the somatic level in a variety of test systems have demonstrated ACN's mutagenicity; its potential to induce mutations in germ cells has also been evaluated. ACN is metabolized to reactive intermediates capable of forming adducts with macromolecules including DNA, a necessary first step in establishing a direct mutagenic mode of action (MOA) for its carcinogenicity. The mutagenicity of ACN has been well demonstrated, however, numerous studies have found no evidence for the capacity of ACN to induce direct DNA lesions that initiate the mutagenic process. Although ACN and its oxidative metabolite (2-cyanoethylene oxide or CNEO) have been shown to bind in vitro with isolated DNA and associated proteins, usually under non-physiological conditions, studies in mammalian cells or in vivo have provided little specification as to an ACN-DNA reaction. Only one early study in rats has shown an ACN/CNEO DNA adduct in liver, a non-target tissue for its carcinogenicity in the rat. By contrast, numerous studies have shown that ACN can act indirectly to induce at least one DNA adduct by forming reactive oxygen species (ROS) in vivo, but it has not been definitively shown that the resulting DNA damage is causative for the induction of mutations. Genotoxicity studies for ACN in somatic and germinal cells are summarized and critically reviewed. Significant data gaps have been identified for bringing together the massive data base that provides the basis of ACN's current genotoxicity profile.

Experimental study of bifacial photovoltaic module with waste polyvinyl chloride flex and acrylonitrile butadiene styrene road side safety sticker as an alternative reflector: optimization using response surface methodology.

Bifacial photovoltaics (PV) are gaining rapid attention and their ability to generate more electricity is accelerating their deployment globally. However, literature on optimal bifacial PV is presented for the installation parameters of the system. In this study, we use response surface methodology (RSM) to investigate the flex and roadside reflector wastes as alternate reflectors for bifacial PV modules by using a statistical model. Our primary objective in this study is to examine the significant influence of key input factors (front irradiation, rear irradiation, temperature, thickness, and height) on the irradiance factor, total solar reflectance, and power extracted. The results show that the power extraction of the bifacial PV module using the waste flex material is 9%, higher than that of the road side sticker waste. The result indicates that among all other input factors, front irradiation is the most significant parameter.

Acrylonitrile butadiene styrene microplastics aggravate the threat of decabromodiphenyl ethane to Eisenia fetida: Bioaccumulation, tissue damage, and transcriptional responses.

Little is known about how brominated flame retardants (NBFRs) and microplastics (MPs) co-pollution influences soil organisms. Here, we investigated the impacts of acrylonitrile butadiene styrene (ABS)-MPs in soil on the 28-d dynamic bioaccumulation, tissue damage, and transcriptional responses of decabromodiphenyl ethane (DBDPE) in Eisenia fetida by simulating different pollution scenarios (10 mg kg-1 DBDPE, 10 mg kg-1 DBDPE accompanied by 0.1 % ABS-MPs, and 10 mg kg-1 DBDPE accompanied by 0.1 % ABS-resin). The results show ABS resin did not influence DBDPE bioaccumulation or distribution, but ABS-MPs, particularly 74-187 µm size of MPs, prolonged DBDPE equilibrium time and significantly promoted DBDPE bioaccumulation in tissue (1.76-2.38 folds) and epidermis (2.72-3.34 folds). However, ABS-MPs and ABS-resin reduced DBDPE concentrations of intestines by 22.2-30.6 % and 37.3 %, respectively. DBDPE-MPs caused more serious epidermis and intestines damages than DBDPE. Additionally, compared to the control, DBDPE significantly up-regulated 1957 genes and down-regulated 2203 genes; meanwhile, DBDPE-MPs up-regulated 1475 genes and down-regulated 2231 genes. DBDPE and DBDPE-MPs both regulated lysosome, phagosome, and apoptosis as the top 3 enriched pathways, while DBDPE-MPs specifically regulated signaling pathways and compound metabolism. This study demonstrated that the presence of ABS-MPs aggravated the biotoxicity of DBDPE, providing scientific information for assessing the ecological risks of MPs and additives from e-waste in soil.

A reevaluation of selected mortality risks in the updated NCI/NIOSH acrylonitrile cohort study.

Objectives: The study aimed to determine whether the National Cancer Institute's (NCI) recent suggestion of associations between acrylonitrile (AN) exposure and mortality in lung and bladder cancer and pneumonitis is robust to alternative methods of data analysis. Materials and methods: We used the Richardson method to indirectly adjust risk ratios (RRs) in relation to AN exposure for potential confounding by smoking and asbestos. We repeated key analyses omitting workers from Plant 4 to account for possible local, historical shipyard-related asbestos exposures. Results: The adjustment of lung cancer RRs for confounding by both smoking and asbestos and omitting Plant 4 workers yielded mostly decreased RRs and much less evidence of a positive association with cumulative AN exposure. Conclusion: Overall, our reanalysis provided little evidence to support NCI's suggestion of associations between AN exposure and mortality in lung and bladder cancer and pneumonitis.

Monitoring the liberation of volatile organic compounds during fused deposition modeling three dimensional printing using solid-phase microextraction coupled to gas chromatography/mass spectrometry.

Three-dimensional (3D) printers have gained tremendous popularity and are being widely used in offices, laboratories, and private homes. Fused deposition modeling (FDM) is among the most commonly used mechanisms by desktop 3D printers in indoor settings and relies on the extrusion and deposition of heated thermoplastic filaments, resulting in the liberation of volatile organic compounds (VOCs). With the growing use of 3D printers, concerns regarding human health have risen as the exposure to VOCs may cause adverse health effects. Therefore, it is important to monitor VOC liberation during printing and to correlate it to filament composition. In this study, VOCs liberated with a desktop printer were measured by solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS). SPME fibers featuring sorbent coatings of varied polarity were chosen for the extraction of VOCs liberated from acrylonitrile butadiene styrene (ABS), tough polylactic acid, and copolyester+ (CPE+) filaments. It was found that for all three filaments tested, longer print times resulted in a greater number of extracted VOCs. The ABS filament liberated the most VOCs while the CPE+ filaments liberated the fewest VOCs. Through the use of hierarchical cluster analysis and principal component analysis, filaments as well as fibers could be differentiated based on the liberated VOCs. This study demonstrates that SPME is a promising tool to sample and extract VOCs liberated during 3D printing under non-equilibrium conditions and can be used to aid in tentative identification of the VOCs when coupled to gas chromatography-mass spectrometry.

The structure and properties of mechanochemically modified acrylonitrile butadiene rubber (NBR)/poly (vinyl chloride) (PVC) scraps and fresh NBR composites.

Vulcanized acrylonitrile-butadiene rubber (NBR)/poly (vinyl chloride) (PVC) blends are mainly served as insulation rubber-plastic materials. However, methods to reuse the waste NBR/PVC composites lack research. Here, we found that the mechanochemically modified waste NBR/PVC composites powders (WNPP) could be an alternative to fresh NBR. According to the results, the optimal replacement amount of WNPP for NBR was 20%, and the highest feasible proportion was 40%. WNPP treated by solid-state shear milling technology (S3M) would have a high degree of desulfurization, and the cross-linked chains within WNPP would be transformed into free chains. While co-vulcanizing, the sulfur agents and heat would induce the free chains of WNPP to react with the polymer chains of the NBR substrate, thereby generating dangling chains to form a robust interfacial layer. It was beneficial for the improvement of the mechanical properties of reclaimed products. And the strain of the excellent recycled sample (20C) reached 707%. Moreover, the modified WNPP in the co-vulcanized rubber represented heterogeneity because of the internal residual crosslinked network and the not-melting PVC plastic phase. Although the heterogeneity of WNPP damaged the continuity of the NBR matrix, it also brought a better hysteresis loss capability to the composite. In conclusion, this work expanded the mechanochemical application scope in recycling NBR/PVC wastes.

The theoretical adhesion of Staphylococcus aureus and Pseudomonas aeruginosa as nosocomial pathogens on 3D printing filament materials.

Microbial infections and nosocomial diseases associated with biomaterial have become a major problem of public health and largely lead to revision surgery, which is painful and quite expensive for patients. These infections are caused by formation of biofilm, which present a difficulty of treatment with conventional antibiotics. The aim of our study is to investigate the theoretical adhesion of Staphylococcus aureus and Pseudomonas aeruginosa on four 3-dimensional printing filament materials used in the manufacture of medical equipment. Thus, the physicochemical properties of these microorganisms and all filament materials were determined using the contact angle measurements. Our results indicated that bacterial surfaces were hydrophilic, strongly electron donating and weakly electron accepting. In contrast, nylon, acrylonitrile butadiene-styrene, polyethylene terephthalate, and polylactic acid surfaces were hydrophobic and more electron-donor than electron-acceptor. In addition, according to the values of total free interaction energy ΔGTotal, Staphylococcus aureus was found unable to adhere to the filament materials except polyethylene terephthalate surface. However, Pseudomonas aeruginosa showed adhesion capacity only for acrylonitrile butadiene-styrene and polyethylene terephthalate surfaces. These findings imply that the usage of these 3D printed materials in the medical area necessitates more research into enhancing their resistance to bacterial adherence.