Insights into the role of VOCs properties on thermal desorption behaviors of two porous polymeric resins.

Desorption is a critical process in the recovery or post-treatment of adsorbents saturated with volatile organic compounds (VOCs). In this study, the thermal desorption behaviors for eight VOCs on hypercrosslinked polymeric resin (HPR) and macroporous polymeric resin (MPR) were investigated through isothermal desorption and temperature programmed desorption (TPD). Compared with MPR, HPR with more micropores exhibited a lower desorption rate constant, lower desorption efficiency and higher desorption activation energy due to the strong binding energy generated between VOCs molecules and narrow micropores. As the polarizability of VOCs increased, the desorption rate constants on two porous polymeric resins decreased, while the desorption activation energy showed an incremental trend. Excellent linear correlations were observed between VOC polarizability and desorption rate constants (R2 = 0.957 for HPR and R2 = 0.940 for MPR) as well as between VOC polarizability and desorption activation energy (R2 = 0.981 for HPR and R2 = 0.969 for MPR). Furthermore, a polyparameter linear free energy relationship (PP-LFER) was developed to explore the influences of intermolecular interactions on desorption behaviors of VOCs on porous polymeric resins. The results indicated that the dispersive interaction, which is directly related to polarizability of VOCs, was the primary factor influencing the desorption activation energy of VOCs on porous polymeric resins. The find from this study helps evaluate fleetly and availably the desorption properties of VOCs based on their polarizability.

Neural network establishes co-occurrence links between transformation products of the contaminant and the soil microbiome.

It remains challenging to establish reliable links between transformation products (TPs) of contaminants and corresponding microbes. This challenge arises due to the sophisticated experimental regime required for TP discovery and the compositional nature of 16S rRNA gene amplicon sequencing and mass spectrometry datasets, which can potentially confound statistical inference. In this study, we present a new strategy by combining the use of 2H-labeled Stable Isotope-Assisted Metabolomics (2H-SIAM) with a neural network-based algorithm (i.e., MMvec) to explore links between TPs of pyrene and the soil microbiome. The links established by this novel strategy were further validated using different approaches. Briefly, a metagenomic study provided indirect evidence for the established links, while the identification of pyrene degraders from soils, and a DNA-based stable isotope probing (DNA-SIP) study offered direct evidence. The comparison among different approaches, including Pearson's and Spearman's correlations, further confirmed the superior performance of our strategy. In conclusion, we summarize the unique features of the combined use of 2H-SIAM and MMvec. This study not only addresses the challenges in linking TPs to microbes but also introduces an innovative and effective approach for such investigations. Environmental Implication: Taxonomically diverse bacteria performing successive metabolic steps of the contaminant were firstly depicted in the environmental matrix.

Effect of high-intensity ultrasound on the structural and functional properties of proteins in housefly larvae (Musca demestica).

Insect protein has gradually attracted wide attention from the international research community as a promising source of high-quality protein that can replace traditional protein sources. The larvae of the housefly, a prevalent and widespread species, contain high levels of protein with beneficial properties, namely, anti-fatigue, anti-radiation, and anti-aging functions, as well as liver protection and immunity enhancement. This work thoroughly examined the impact of high-intensity ultrasound (HIUS) on the structural and functional characteristics of housefly larval concentrate protein (HLCP). HLCP samples were sonicated for 20 min at a frequency of 20 kHz with varying energies (0, 100, 200, 300, 400, and 500 W). The findings demonstrated that sonication considerably altered the secondary and tertiary structures of HLCP but had no effect on molecular weight. With an increase in ultrasonic power, HLCP's particle size shrank, more hydrophobic groups were exposed, more free sulfhydryl groups were present, the solution's stability improved, and HLCP's solubility rose. In addition, HLCP's emulsification and foaming abilities were improved by HIUS treatment. It is anticipated that this study's findings will offer fresh insights into the implementation of HLCP in the food sector.

Investigation on Nanocomposites of Polysulfone and Different Ratios of Graphene Oxide with Structural Defects Repaired by Cellulose Nanocrystals.

In this manuscript, nanofillers of graphene oxide (GO) and cellulose nanocrystal (CNC) with different weight ratios (G/C ratios), named GC 2:1, GC 4:1, GC 8:1, GC 16:1, and GC 32:1, were successfully prepared. Characterization methods such as Raman spectroscopy, X-ray photoelectron spectrometry (XPS), and thermogravimetric analysis (TGA) were performed. Additionally, the effects of these samples on the thermal stability, mechanical properties, and gas barrier properties of polysulfone (PSF) nanocomposites were investigated. A hydrophilic interaction took place between CNC and GO; as a consequence, CNCs were modified on the surface of GO, thus repairing the structural defects of GO. With the increase in G/C ratios, the repair effect of insufficient CNCs on the defects of GO decreased. The G/C ratio had a great influence on the improvement of mechanical properties, thermal stability, and gas barrier properties of nanocomposites. Compared with PSF/GC 2:1 and PSF/GC 32:1, the differences in the growth rates of tensile strength, elongation at break, and Young's modulus were 30.0%, 39.4%, and 15.9%, respectively; the difference in Td 3% was 7 °C; the difference in decline rate of O2 permeability was 40.0%.

Effect of thread depth and thread pitch on the primary stability of miniscrews receiving a torque load : A finite element analysis.

PURPOSE: We have been developing a new type of miniscrew to specifically withstand orthodontic torque load. This study aimed to investigate the effect of thread depth and thread pitch on the primary stability of these miniscrews if stressed with torque load. METHODS: Finite element analysis (FEA) was used to evaluate the primary stability of the miniscrews. For thread depth analysis, the thread depth was set to 0.1-0.4 mm to construct 7 models. For thread pitch analysis, the thread pitch was set to 0.4-1.0 mm to construct another 7 models. A torque load of 6 Nmm was applied to the miniscrew, and the other parameters were kept constant for the analyses. Maximum equivalent stress (Max EQV) of cortical bone and maximum displacement of the miniscrews (Max DM) were the indicators for primary stability of the miniscrew in the 14 models. RESULTS: In the thread depth analysis, Max DM increased as the miniscrew thread depth increased, while Max EQV was smallest in model 3 (thread depth = 0.2, Max EQV = 8.91 MPa). In the pitch analysis, with an increase of the thread pitch, Max DM generally exhibited a trend to increase, while Max EQV of cortical bone showed a general trend to decrease. CONCLUSION: Considering the data of Max DM and Max EQV, the most appropriate thread depth and thread pitch of the miniscrews in our model was 0.2 and 0.7 mm, respectively. This knowledge may effectively improve the primary stability of newly developed miniscrews.

Removable partial prosthesis combined with swallowing training is an efficient clinical solution for oral cancer post-operation patients with palatal defect and dysphagia: a prospective study.

OBJECTIVE: Dysphagia is one of the major complications of oral cancer patients, and is disturbing thousands of patients worldwide. Our study aim to evaluate the clinical efficacy of prosthesis combined with swallowing training on palatal defect and dysphagia in post-operative oral cancer patients. MATERIALS AND METHODS: Sixteen oral cancer patients with palatal defect and dysphagia post-operation were treated with removable prosthesis and individualized swallowing function training. Swallowing function of patients before and after treatment was analyzed and compared by videofluoroscopic swallowing examination. The severity of depression and life quality were evaluated by Depression Scale (SDS) and Functional Assessment of Cancer Therapy-Head and Neck (FACT-H&N) scores, respectively. RESULTS: Oral transit time (OTT) significantly shortened after treatment (P < 0.01), and Penetration-Aspiration Scale (PAS) scores was significantly higher after treatment (P < 0.001). Different consistency bolus showed different risk of aspiration. Thickened liquids were related to lower PAS scores (P < 0.001). SDS standard score was significantly lower after treatment (P < 0.05). The total score of FACT-H&N after treatment was significantly higher (P < 0.05). No patients came back for regressed swallowing function during the follow-up period (17.06 ± 2.376 months). CONCLUSION: Removable prosthesis and swallowing training can significantly improve swallowing function, reduce depression degree, and improve quality of life (QOL). CLINICAL RELEVANCE: Removable prosthesis combined with swallowing training is a cheap and effective method to improve QOL in patients with palate defect and dysphagia after oral cancer.

Reconstruction of Large Acquired Palatal Defects Using Facial-Submental Artery Island Flap.

OBJECTIVE: To evaluate the feasibility and clinical effect of facial-submental artery island flap (FSAIF) in the repair of palatal defects, and to provide reference for the clinical application of submental artery island flap. METHODS: Nine patients with palatal defects, the range of nasal palatal perforation defects were 3 cm × 4cm to 3 cm × 6 cm (median 3 cm × 5.4 cm), were repaired by FSAIF, and the sizes of FSAIF were 4 cm × 9cm to 4 cm × 12 cm (median 4 cm × 10.4 cm,). Postoperative clinical efficacy was evaluated, including infection and necrosis of mucosal flap and postoperative palatal fistula perforation. Patients were followed up to evaluate their chewing, swallowing, speech function, and satisfaction of appearance. RESULTS: All patients were successfully repaired with FSAIF. Followed up 13∼35 months, there was no palatal fistula perforation in all patients. The speech, agitation, and swallowing function were not affected and the patients were satisfied with the appearance. CONCLUSION: FSAIF is a safe and reliable method for palatal defect repair.

Thread shape affects the stress distribution of torque force on miniscrews: a finite element analysis.

This study aimed to investigate the effect of miniscrews thread shape on the stress distribution receiving a torque load. Seven thread shapes (S,V1,V2,B1,B2,R1,R2) models were constructed and a 6 Nmm-torque load was applied. The order of maximum equivalent stress (EQV) value was V1 > V2 > B1 > R1 > R2 > B2 > S. The order of maximum displacement of miniscrew (Max DM) value was S > B2 > R1 = V1 > B1 > V2 > R2. Model R2 may be the most appropriate thread shape affording a torque force.

Adsorption of low-concentration VOCs on various adsorbents: Correlating partition coefficient with surface energy of adsorbent.

Accurately evaluating the adsorption properties of various adsorbents by some parameter is of great significance to select an appropriate adsorbent and remove volatile organic compounds (VOCs) efficiently. In this study, we successfully found a new parameter as a common standard in selecting adsorbents. Six classical adsorbents containing three carbon materials and three porous polymeric resins were used, and their surface energy (γst) and corresponding gas-solid partition coefficients (K) of eleven VOCs were measured by inverse gas chromatography (IGC) at three different column temperatures of 343 K(or 353 K), 373 K and 403 K. Then, these values at 303 K were calculated according to the linear relationship between lnK and 1/T. It was found that surface energy was significantly correlated with K values for a specific VOC, and could be used as a common standard to well evaluate the adsorption properties of various adsorbents. Furthermore, we employed it to develop a model for predicting the adsorption properties of low-concentration VOCs on various adsorbents at 303 K. The developed model exhibited an excellent predictive ability by external validation. Moreover, the model showed wide applicability and predicted the lnK values of VOCs at 373 K and 403 K in R2 of 0.910 and 0.889.

The Long Non-coding RNA lnc-DMP1 Regulates Dmp1 Expression Through H3K27Ac Modification.

Several long non-coding RNAs (lncRNAs) have been reported regulate the expression of neighbor protein-coding genes at post-transcriptional, transcriptional and epigenetic levels. Dmp1 (Dentin matrix protein 1), encoding a non-collagenous extracellular matrix protein, plays an important role in dentin and bone mineralization. However, the transcriptional regulation of lncRNA on Dmp1 has not been reported. In this study, we identified a novel lncRNA named lnc-DMP1, which is near the Dmp1 gene region and undergoes remarkable changes during mandible development. lnc-DMP1 is co-localized and significantly expressed correlation with Dmp1 in embryonic and postnatal mouse mandibles. In MC3T3-E1 cells, lnc-DMP1 positively regulates DMP1 expression and skeletal mineralization. Furthermore, lnc-DMP1 induces the promoter activity of Dmp1 by modulating H3K27Ac enrichment in the Dmp1 promoter. In conclusion, our results indicate that lnc-DMP1 is a novel lncRNA near the Dmp1 gene region and regulates Dmp1 expression by modulating the H3K27 acetylation level of Dmp1 promoter.

Investigation on the Effect of Hyperbranched Polyester Grafted Graphene Oxide on the Crystallization Behaviors of ß-Nucleated Isotactic Polypropylene.

In this article, hyperbranched polyester grafted graphene oxide (GO) was successfully prepared. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) were performed for its characterizations. On the other hand, differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) were also performed to study its influences on non-isothermal crystallization behaviors of ß-nucleated isotactic polypropylene (ß-iPP). The grafting ratios of hyperbranched polyester with different supermolecular structures were calculated to be 19.8-24.0 wt %, which increase with the degree of branching. The results showed that the grafting of hyperbranched polyester was advantageous in increasing the crystallization peak temperature Tp and decreasing the crystallization activation energy ΔE of ß-iPP/GO composites, which contributed to the iPP's crystallization process. Moreover, under all cooling rates (2, 5, 10, 20, 40 °C/min), crystallinities of ß-iPP/GO were greatly improved after being grafted with hyperbranched polyester, because of the increase of the relative contents of α-phase αc and the average α-crystal sizes.

Predicting adsorption coefficients of VOCs using polyparameter linear free energy relationship based on the evaluation of dispersive and specific interactions.

Predicting adsorption of volatile organic compounds (VOCs) on activated carbons is of major importance to understand activated carbons' adsorption properties and explore their potential applications. In this study, adsorption of 38 VOCs on a commercial granular activated carbon (GAC) was examined using inverse gas chromatography (IGC) at infinite dilution, and the adsorption coefficients (K), dispersive and specific components of adsorption free energy were calculated. We found that the dispersive interaction was well described by adsorbate's molar polarizability (P), and the specific interactions well by dipolarity/polarizability (S), hydrogen-bond acidity (A) and hydrogen-bond basicity (B). Based on the result, a polyparameter linear free energy relationship (PP-LFER) was established: logK = (0.96 ±â€¯0.23) S + (2.23 ± 0.34) A + (0.84 ± 0.25) B + (0.69 ± 0.050) P + (0.13 ± 0.35); (n = 38, R2 = 0.859, root mean square error (RMSE) = 0.25), which exhibited a more accurate prediction compared to the classical PP-LFER (E, S, A, B and L as descriptors, R2 = 0.765, RMSE = 0.33). Moreover, it overcame the drawbacks of indistinguishable dispersive interaction and unavailable relative contribution of each interaction for classical PP-LFER in explaining adsorption mechanism. As suggested by the developed model, the dispersive interaction was the dominant contribution to the adsorption of VOCs on GAC (42-100%), following by dipole-type interactions (0-30%) and hydrogen bonding (hydrogen-bond acidity 0-32%, hydrogen-bond basicity 0-11%). Additionally, it also accurately predicted the K values of VOCs on other three activated carbons.

Exploring the Effects of Stereo-Defect Distribution on Nonisothermal Crystallization and Melting Behavior of ß-Nucleated Isotactic Polypropylene/Graphene Oxide Composites.

In this work, using two isotactic polypropylene (iPP) resins with similar average isotacticity and molecular weight but different uniformities of stereo-defect distribution, the ß-nucleated iPP/graphene oxide (ß-iPP/GO) composites (NPP-A and NPP-B) were prepared to investigate the effect of stereo-defect distribution on the nonisothermal crystallization kinetics and polymorphic melting behavior of the composites by means of scanning electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry. The results showed that more uniform stereo-defect distribution led to a slight increase of the crystallization rate and decrease of the crystallization activation energy E c. NPP-B with more uniform stereo-defect was more favorable for the formation of a large amount of ß-phase. Moreover, the role of the cooling rate was also discussed and it was found that the higher the cooling rate, the higher the ß-phase content and the smaller the crystalline sizes, meanwhile, the higher the amount of ß-phase with relatively lower thermal stability that will take part in ß-α recrystallization during the subsequent melting process. For ß-iPP/GO composites, although the cooling rate greatly influences the polymorphic behavior and crystalline structures of the composites, the uniformity of stereo-defect distribution was found to be the first factor determining the formation of the ß-phase.

Ordered structure effects on ß-nucleated isotactic polypropylene/graphene oxide composites with different thermal histories.

In this paper, the influence of ordered structure effects (OSE) on crystallization behaviors of ß-nucleated isotactic polypropylene/graphene oxide (ß-iPP/GO) composites with different thermal histories, which crystallized at a slow cooling rate (called SLOW), fast cooling rate (called FAST) and medium cooling rate (called MED), respectively, was studied by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). The ordered structure status of three samples before crystallization measurement was controlled by tuning the fusion temperature T f and melting time t m. The results showed that for all samples, OSE would occur in an appropriate T f region (Region II). The OSE efficiency of MED was the highest, while that of SLOW were the lowest. It was also found that the crystallinity and crystalline perfection of SLOW were the highest, while those of FAST were the lowest. The effects of the melting time t m on the OSE were also investigated. At T f = 172 °C, the OSE efficiency of FAST reached the maximum at t m = 5 min, while that of SLOW reached the maximum at t m = 20 min. It was indicated that the OSE efficiency was affected by thermal history, and it could be improved by selecting the appropriate t m. Related mechanisms concerning the roles of thermal history on the OSE behavior were proposed based on the results of DSC and in situ SAXS.

Finite Element Analysis of Bone Stress around Micro-Implants of Different Diameters and Lengths with Application of a Single or Composite Torque Force.

BACKGROUND: Stress on the bone surrounding dental micro-implants affects implant success. PURPOSE: To compare the stress on the bone surrounding a micro-implant after application of a single force (SF) of 200 g or a composite force (CF) of 200 g and 6 N.mm torque. MATERIALS AND METHODS: Finite element models were developed for micro-implant diameters of 1.2, 1.6, and 2.0 mm, and lengths of 6, 8, 10, and 12 mm and either a SF or CF was applied. The maximum equivalent stress (Max EQS) of the bone surrounding the micro-implant was determined, and the relationships among type of force, diameter, and length were evaluated. RESULTS: The Max EQS of the CF exceeded that of the SF (P< 0.05). The effect of force on stress was related to implant diameter, but not to implant length. The larger CF led to greater instability of the micro-implant and the effect was most pronounced at an implant diameter of 1.2 mm. The use of implant diameters of 1.6 mm and 2.0 mm produced no significant difference in implant stability when either a CF or SF was applied. CONCLUSION: When considering the use of an implant to perform three-dimensional control on the teeth, the implant diameter chosen should be > 1.2 mm.

Analysis on the stress of the bone surrounding mini-implant with different diameters and lengths under torque.

The purpose of this study is to compare the stress of the bone around the mini-implant under the two kinds of force: the composite force which contains torque and traditional single force. There were 96 finite element models formed by the combination of mini-implant and bone, with diameters of 1.2 mm, 1.6 mm, 2.0 mm and corresponding length being 6 mm, 8 mm, 10 mm, 12 mm, respectively. Each size corresponded to 8 models. Group SF (each size n=4) was loaded with 200 g single force, while Group CF (each size n=4) was loaded with composite force which contained 6N mm torque and 200 g single force. The maximum equivalent stress (Max EQS) of the bone surrounding mini implant with different loading directions was calculated, and the relationship of force direction, diameter and length was also evaluated. The Max EQS of Group CF was higher than that of Group SF. The effect of force direction on the stress was related to the diameter of mini implant, but had nothing to do with its length. The Max EQS of the cortical bone around mini implant in Group CF was higher (P<0.05) than that in Group SF. In contrast, there was no significant difference (P>0.05) between Group SF and Group CF in terms of bone stress when the diameter of mini implant was 1.6 mm or 2.0 mm. In our study, it is demonstrated that the diameter of mini-implant is better to be larger than 1.2 mm when a mini-implant is used in a torque control of tooth. The impact of this feature in the clinical setting needs to be verified.

[Selection of optimal length and diameter of mini implant in two different forces: a three-dimensional finite element analysis].

OBJECTIVE: To investigate the effect of different length and diameters on the stability of mini implant and to select optimal length and diameter using continuous variation of parameters. METHODS: To perform 3-dimensional finite element analysis, finite element models of a maxilla, and mini implants with length of 6-12 mm and diameters of 1.2-2.0 mm were generated. Load of two different forces were applied to the head of mini implant. One type was horizontal force (HF), the other was composite force (CF). The maximum equivalent stress (Max EQV) in maxilla and the maximum displacement (Max DM) of mini implant were evaluated. RESULTS: The Max EQV in maxilla and Max DM of mini implant decreased as length and diameter increased. When length was more than 9 mm, the evaluation indexes were small and had a less change. Datas indicated that diameter played a more important role in reducing target, and was a more effective parameter in reducing Max EQV when CF was loaded. CONCLUSION: From biomechanical point of view, the choice of the length should not be more than 9 mm. When CF is loaded using the mini implant, diameter exceeding 1.2 mm are optimal design for mini implant.

[Influence of the diameter and length of the mini-implant on the primary stability after loading with composite forces].

OBJECTIVE: To investigate the influence of the diameter and length of the mini-implant on the primary stability after loading with composite forces (CF) which contained torque and horizontal forces (HF). METHODS: Ninety-six finite element models were established by the combination of mini-implant and bone, diameters (1.2 mm, 1.6 mm, 2.0 mm) and length (6 mm, 8 mm, 10 mm, 12 mm). There were 12 sizes, each size corresponded with 8 models. Group HF (each size n = 4) was loaded with 1.96 N horizontal force and Group CF (each size n = 4) was loaded with composite force which contained 6 N·mm torque and 1.96 N horizontal force. The maximum displacement of mini-implant with different force directions, implant diameters and lengths were evaluated. RESULTS: The effect of force direction on the displacement related to diameter of mini-implant. The maximum displacement under load with HF respectively was changed with the changing of diameter[1.2 mm: (7.71 ± 0.49) µm; 1.6 mm: (3.94 ± 0.31) µm; 2.0 mm: (2.32 ± 0.43) µm], which were smaller than the maximum displacement of Group CF [1.2 mm: (9.22 ± 0.63) µm; 1.6 mm: (4.62 ± 0.52) µm; 2.0 mm: (2.69 ± 0.49) µm] (P < 0.05). When diameter was 1.2 mm, the difference of the maximum displacement [(1.61 ± 0.22) µm] between Group HF and CF was more obvious than that when the diameter was 1.6 mm or 2.0 mm [(0.64 ± 0.12), (0.49 ± 0.06) µm] (P < 0.05). CONCLUSIONS: The composite force had unfavorable effect on the primary stability of the mini-implant. The diameter of the mini-implant had better be larger than 1.2 mm when the composite forces were applied.