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Suicidal ideation is an important public health challenge among people living with HIV (PLWH) across the world and in China. HIV stigma, depression, and self-esteem have been associated with suicidal ideation. However, the underlying mechanisms remain not fully understood.Study data were derived from a sample of 465 PLWH in China. Suicidal ideation after HIV diagnosis was used as outcome variable. HIV stigma, depressive symptoms, and self-esteem were measured using reliable instruments and used as predictor, mediator, and moderator, respectively. Mediation and moderated mediation model were used for data analysis.31.6% of PLWH in China had suicidal ideation after HIV diagnosis. The association between perceived HIV stigma and suicidal ideation was partially mediated by depression (indirect effect = 0.02, 95% CI = [0.02, 0.03]) with the path from perceived HIV stigma to depressive symptoms being moderated by self-esteem (interaction effect = - 0.02, 95% CI [- 0.03, - 0.01]).Study findings suggested a mediation mechanism of HIV stigma on suicidal ideation through depressive symptoms, and self-esteem might weaken the mediation mechanism by moderating the perceived HIV stigma-depressive symptoms pathway.

Purpose: Lacrimal sac space-occupying lesions (SOLs) are rare and sometimes life-threatening disorders, often misdiagnosed in clinical practices. This study aimed to observe the imaging features of Color Doppler ultrasound (CDU) and computed tomography (CT) or computed tomography dacryocystography (CT-DCG) in different types of lacrimal sac SOLs. Methods: This retrospective case series study included 21 patients with lacrimal sac SOLs who underwent lacrimal sac surgery between January 2018 and March 2022. The imaging features of CDU and CT or CT-DCG in these patients extracted from the examination cloud system were observed and analyzed. Results: 21 patients with lacrimal sac SOLs completed preoperative CDU and CT or CT-DCG examination. CDU showed abnormal lacrimal sac imaging in all cases of SOLs (21/21, 100%), while CT or CT-DCG showed abnormal imaging in 20 cases (20/21, 95.2%). CDU could detect the blood flow signals in all types of space-occupying lesions except mucocele and mucopeptide concretion. Among them, polyps had characteristic imaging changes on CDU and CT-DCG. The mucoceles and mucopeptide concretions had characteristic imaging changes on CDU, which could provide more information for differential diagnosis. Conclusions: CDU can observe the morphology and internal blood flow signals of lacrimal sac SOLs. CT or CT-DCG has advantages in observing structural damage around the lacrimal sac mass. Therefore, CDU may be used as a routine examination to exclude lacrimal sac SOLs before DCR in the absence of preoperative CT or CT-DCG.

OBJECTIVE Diabetic macular edema (DME) is one of the most frequent causes of severe vision loss. The pathogenesis of DME is still not fully understood; however, it is hypothesized to result from breakdown of the blood-retinal barrier (BRB) due to retinal inflammation by vascular endothelial growth factor (VEGF) secretion under hyperglycemic conditions. In this investigation, we discovered that Prolyl-4-hydroxylase 2 (PHD2), an upstream regulator of hypoxia-inducible factor 1 (HIF-1) modulates VEGF expression and thus preserves BRB function in the mouse retina. MATERIALS AND METHODS Primary human retinal microvascular endothelial cells (hRMECs) were cultured in human endothelial serum-free growth medium and exposed to hyperglycemia. Changes in cell viability were investigated by an MTT assay. BRB function in each group was revealed by a paracellular permeability assay and trans-endothelial electrical resistance (TEER). Morphological changes in the BRB were investigated by immunofluorescence staining of occludin and zonula occludens-1 (ZO-1). The mRNA and protein levels of the tight junction proteins, PHD2, HIF-1α, and VEGF were measured by reverse transcription-quantitative PCR (RT-qPCR), western blot analysis and ELISA. RESULTS Under hyperglycemic conditions, the viability of hRMECs was decreased, and PHD2 expression was downregulated, accompanied by increased paracellular permeability and decreased trans-endothelial electrical resistance. Additionally, HIF-1α and VEGF expression levels were increased, whereas the expression levels of tight junction proteins, including occludin and ZO-1, were decreased and BRB function was compromised. The PHD2 activator R59949 (diacylglycerol kinase inhibitor II), altered these pathological changes, and the PHD2 inhibitor dimethyloxalylglycine (DMOG) resulted in the opposite effects. CONCLUSION These results demonstrated that PHD2 inhibited HIF-1 activity by inhibiting HIF-1α expression in hRMECs under hyperglycemic conditions, which led to the downregulation of the expression of the angiogenic factor VEGF, and thus helped to maintain the functions of hRMECs. Therefore, it is reasonable to propose that PHD2 could be a potential novel target for the treatment of DME or other diseases with a similar pathogenesis.

To evaluate the efficacy and risk of cataract surgery (phacoemulsification with intraocular lens [IOL] implantation) combined with endoscopic goniosynechialysis (EGSL) for advanced primary angle-closure glaucoma (PACG).Retrospective, continuous case series.A total of 16 patients (18 eyes) with advanced PACG were enrolled in this study between February 2014 and March 2016. Advanced glaucoma inclusion criteria were based on the method proposed in the Advanced Glaucoma Intervention Study, with a visual field score of 18 points or more.All patients underwent cataract surgery with EGSL by the same experienced surgeon. Paired t test and generalized estimating equation analyses were performed.The extent of peripheral anterior synechiae (PAS), number of intraocular pressure (IOP)-lowering drugs, IOP, best-corrected visual acuity (BCVA), and visual fields before and after surgery. The incidence of complications was recorded.The mean follow-up duration was 13.8 months (standard deviation, 2.7 months). The mean difference (preoperative minus postoperative) in PAS was 202.7° (95% confidence interval [CI], 43.5°). The mean difference (preoperative minus postoperative) in the number of IOP-lowering drugs and IOP was 2.0 (95% CI, ±0.5), and 9.4 mmHg (95% CI, ±2.1 mmHg) respectively. The mean improvement in BCVA was 0.29 logMAR (95% CI, ±0.14). A positive correlation was found between the extent of postoperative PAS and postoperative IOP (B = 8.2; P0.001) and also between postoperative PAS and postoperative number of IOP-lowering drugs (B = 28.9; P0.001). Anterior chamber hemorrhage and exudation occurred in 4 patients and 2 patients, respectively, after surgery. Posterior capsular opacification occurred in 5 patients after surgery.Cataract surgery with EGSL could be an effective surgical method for the treatment of advanced PACG.

Hydrogen has attracted worldwide attention due to its renewable and pollution-free advantages. Hydrogen fuel cell vehicles have become an important direction for the development of the automotive industry. Carbon fiber reinforced composite hydrogen storage cylinder with plastic liner (Type IV hydrogen storage cylinder) is the main research direction of vehicle hydrogen storage because of its lightweight and excellent resistance to fatigue and corrosion. However, its safety still receives much concern. In this paper, the burst pressure prediction model of type IV hydrogen storage cylinder was established by the user subroutine UMAT of finite element calculation software ABAQUS based on the Hashin failure criterion and the damage evolution law of carbon fiber composite. The damage evolution behavior of carbon fiber winding layer of the cylinder in the process of loading was analyzed. In addition, the influence of winding thickness, winding sequence and winding angle on the burst pressure was obtained.

Background: Despite the relationship between Adverse childhood experiences (ACEs) and depressive symptoms, which has been well conducted in general populations, little is known about homosexual and bisexual populations, especially female sexual minorities in China. This study aims to investigate the prevalence of ACEs and depressive symptoms and to analyze the relationship between them among female sexual minorities in China.Methods: The eligible participants were aged 16 years or older who report their sexual orientation as homosexual or bisexual. The data was collected through anonymous questionnaires under the help of Lespark in Bejing from July 18 to December 29, 2018. Univariate analysis and multiple linear regression analyses were performed to explore the relationship between ACEs and depressive symptoms among female sexual minorities. All statistical analyses were conducted by the software of SPSS 22.0.Results: Among 301 female sexual minorities,51.5% reported at least one ACE, in which emotional neglect (22.6%) and emotional abuse (22.3%) were common ACEs. 24.6% reported that they had suffered only one type of ACE, and 10% have suffered four or more ACEs. As for depressive symptoms of female sexual minorities, the detection rate was 56.1%. The multiple linear regression analyses showed that abuse (β=2.95, p＜0.05) and neglect (β=3.21,p＜0.05) were positively correlated with depressive symptoms and female sexual minorities with three (β=4.11, p＜0.05) or more (β=6.02, p＜0.001) ACEs suffered from more depressive symptoms than others. Conclusion: Both ACEs and depressive symptoms were at high prevalence among female sexual minorities in China. ACEs were associated with depressive symptoms, especially childhood abuse and neglect experiences that have a significant effect on female sexual minorities’ mental health.

Background: Previous studies reported that N-myc downstream-regulated gene 1 (NDRG1) was upregulated in various cancer tissues and decreased expression of miR-188-3p and miR-133b could suppress cell proliferation, metastasis, and invasion and induce apoptosis of cancer cells. However, the molecular mechanism of NRDG1 involved in hepatocellular carcinoma (HCC) tumorigenesis is still unknown. Methods: The expressions of miR-188-3p, miR-133b, and NRDG1 in HCC tissues and cells were quantified by qRT-PCR and Western blot. MTT assay and transwell invasion assay were performed to evaluate cell growth and cell migration, respectively. Luciferase reporter assay were performed to determine whether miR-188-3p and miR-133b could directly bind to NRDG1 in HCC cells. Results: The results showed that NRDG1 was upregulated and these 2 microRNAs were downregulated in HCC tissues. NRDG1 was negatively correlated with miR-188-3p and miR-133b in HCC tissues. MiR-188-3p and miR-133b were demonstrated to directly bind to 3′UTR of NRDG1 and inhibit its expression. Upregulation of miR-188-3p and miR-133b reduced NRDG1 expression in hepatocellular carcinoma cell lines, which consequently inhibited cell growth and cell migration. Conclusions: Our finding suggested that miR-188-3p and miR-133b exert a suppressive effect on hepatocellular carcinoma proliferation, invasion, and migration through downregulation of NDRG1.

Phacoemulsification and goniosynechialysis (Phaco-GSL) was equally effective in the treatment of primary angle-closure disease (PACD) with preoperative peripheral anterior synechiae (PAS)180 degrees and larger than 180 degrees. Patients with a larger preoperative PAS range required more range of mechanical separation intraoperatively and displayed more recurrence of PAS (re-PAS) range postoperatively.To evaluate the long-term efficacy of combined phaco-GSL in PACD with different extent of PAS.A retrospective study was conducted on 67 patients (79 eyes) who received phaco-GSL. The patients were divided into 2 groups according to the extent of PAS (group A: PAS ≤180 degrees; group B: PAS180 degrees). Changes in intraocular pressure (IOP), the number of anti-glaucoma drugs, intraoperative mechanical separation of PAS and range of re-PAS during the last follow-up ≥12 months were analyzed.At baseline, eyes in group B presented with higher IOP and more anti-glaucoma drugs usage ( P =0.008 and 0.004). The PAS range, IOP, number of anti-glaucoma medication were reduced both in 2 groups at the final visit. The range of mechanical separation intraoperatively and re-PAS postoperatively were both larger in group B ( P =0.002 and0.001). The postoperative re-PAS range was positively correlated with the range of mechanical separation ( R2 =0.17). The complete success rates at 12, 24, 36, and 48 months were 86.8%, 71.1%, 71.1%, and 71.1% in group A; and 80.5%, 74.6%, 69.9%, and 69.9% in group B. The qualified success rates were 100%, 96.6%, 92.0%, and 92.0% in group A; and 100%, 89.5%, 85.1%, and 85.1% in group B.Phaco-GSL for the treatment of PACD showed equally effective IOP control regardless of the extent of preoperative PAS.

Thermal imaging technology is widely used in various fields, such as security, defense, medicine and spaceborne applications in the Geo-synchronous Earth Orbit. Most thermal imaging systems operate in the long-wave infrared (LWIR) range or the medium-wave infrared (MWIR) range. However, the longer the wavelength is, the more difficult the imaging system is to provide high resolution due to diffraction limit. Compared to MWIR and LWIR imagers, a short-wave infrared (SWIR) imager achieves higher resolution owing to its higher diffraction limit. However, radiation from an object at 300 k in the SWIR band is weaker than that in the MWIR and LWIR bands. Therefore, the sensitivity is low. With the rapid development of detector technology, the sensitivity of SWIR detector is improved by low dark current and noise. It exhibits good performance in thermal imaging applications. In order to validate SWIR thermal imaging key performance, this study analyzes the thermal imaging capability of an SWIR imager compared to MWIR and LWIR. The noise equivalent temperature differences (NETDs) of SWIR, MWIR, and LWIR imagers for thermal imaging applications are calculated. A compact SWIR imager prototype covering a spectral range of 2.0–2.7 μm is designed and implemented. The facial thermal imaging experiment proves that the high-sensitivity SWIR imager can obtain high-quality thermal images with an NETD of 24 mK at a temperature of 310 K. In addition, in the continuous integration and multiple read-out (IMRO) imaging mode, the dynamic range of the system is extended by 20 dB. The theoretical analysis and experiment show that the SWIR imager can provide high sensitivity with long integration time. In addition, SWIR thermal imaging can provide higher resolution than MWIR and LWIR imagers. Therefore, SWIR imager has considerable potential for high-sensitivity thermal imaging applications in Geo-synchronous Earth Orbit.

Diabetic macular edema (DME) is one of the most frequent causes of severe vision loss. The pathogenesis of DME is still not fully understood; however, it is hypothesized to result from breakdown of the blood-retinal barrier (BRB) due to retinal inflammation by vascular endothelial growth factor (VEGF) secretion under hyperglycemic conditions. In this investigation, we discovered that Prolyl-4-hydroxylase 2 (PHD2), an upstream regulator of hypoxia-inducible factor 1 (HIF-1) modulates VEGF expression and thus preserves BRB function in the mouse retina.Primary human retinal microvascular endothelial cells (hRMECs) were cultured in human endothelial serum-free growth medium and exposed to hyperglycemia. Changes in cell viability were investigated by an MTT assay. BRB function in each group was revealed by a paracellular permeability assay and trans-endothelial electrical resistance (TEER). Morphological changes in the BRB were investigated by immunofluorescence staining of occludin and zonula occludens-1 (ZO-1). The mRNA and protein levels of the tight junction proteins, PHD2, HIF-1α, and VEGF were measured by reverse transcription-quantitative PCR (RT-qPCR), western blot analysis and ELISA.Under hyperglycemic conditions, the viability of hRMECs was decreased, and PHD2 expression was downregulated, accompanied by increased paracellular permeability and decreased trans-endothelial electrical resistance. Additionally, HIF-1α and VEGF expression levels were increased, whereas the expression levels of tight junction proteins, including occludin and ZO-1, were decreased and BRB function was compromised. The PHD2 activator R59949 (diacylglycerol kinase inhibitor II), altered these pathological changes, and the PHD2 inhibitor dimethyloxalylglycine (DMOG) resulted in the opposite effects.These results demonstrated that PHD2 inhibited HIF-1 activity by inhibiting HIF-1α expression in hRMECs under hyperglycemic conditions, which led to the downregulation of the expression of the angiogenic factor VEGF, and thus helped to maintain the functions of hRMECs. Therefore, it is reasonable to propose that PHD2 could be a potential novel target for the treatment of DME or other diseases with a similar pathogenesis.

ANXA1, which can bind phospholipid in a calcium dependent manner, is reported to play a pivotal role in tumor progression. However, the role and mechanism of ANXA1 involved in the occurrence and development of malignant glioma are still not well studied. Therefore, we explored the effects of ANXA1 on normal astrocytes and glioma cell proliferation, apoptosis, migration and invasion and the underlying mechanisms. We found that ANXA1 was markedly up-regulated in glioma cell lines and glioma tissues. Down-regulation of ANXA1 inhibited normal astrocytes and glioma cell proliferation and induced the cell apoptosis, which suggested that the consequences of loss of Annexin 1 are not specific to the tumor cells. Furthermore, the siRNA-ANXA1 treatment significantly reduced tumor growth rate and tumor weight. Moreover, decreasing ANXA1 expression caused G2/M phase arrest by repressing expression levels of cdc25C, cdc2 and cyclin B1. Interestingly, ANXA1 did not affect the expressions of β-catenin, GSK-3β and NF-κB, the key signaling molecules associated with cancer progression. However, siRNA-ANXA1 was found to negatively regulate phosphorylation of AKT and the expression and activity of MMP2/-9. Finally, the decrease of cell proliferation and invasiveness induced by ANXA1 down-regulation was partially reversed by combined treatment with AKT agonist insulin-like growth factor-1 (IGF-1). Meanwhile, the inhibition of glioma cell proliferation and invasiveness induced by ANXA1 down-regulation was further enhanced by combined treatment with AKT inhibitor LY294002. In summary, these findings demonstrate that ANXA1 regulates proliferation, migration and invasion of glioma cells via PI3K/AKT signaling pathway.

The study explored the associations between maternal exposure to air pollution during different trimesters and allergic diseases including asthma, allergic rhinitis, allergic conjunctivitis or/and eczema. Individual exposure to air pollutants was assessed by an inverse distance weighted (IDW) method using daily concentrations of SO2, NO2, PM10, and PM2.5 from air quality monitoring stations. Multiple logistic regression model was performed to estimate the associations between air pollution during each trimester of pregnancy and childhood allergic diseases. A total of 332 children (51.3%) were reported by their parents having been diagnosed with allergic diseases. After adjusting for covariates, allergic diseases were significantly associated with per interquartile range (IQR) increase in NO2, PM10, PM2.5 during the second trimester with odds ratios (ORs) and 95% confidence intervals (95%CIs) being 1.292 (1.005,1.662), 1.210 (1.042,1,405) and 1.270 (1.004,1.606), respectively. These findings suggest that maternal exposure to certain air pollutants during pregnancy, especially in the second trimester, is associated with childhood allergic diseases.

Background Increasing prevalence of risky sexual behaviors among men who have sex with men (MSM) exacerbate the transmission of HIV. Previous studies had demonstrated that childhood sexual abuse (CSA) was associated with one or more sexual behaviors, but few studies have been conducted among MSM in China. Objective This present study aimed to estimate latent classes of risky sexual behaviors and test for CSA differences in latent class memberships among Chinese MSM. Participants and setting The eligible participants were MSM aged 16 years or older who reported ever having oral or anal sex with men in the past 6 months. Methods Data were obtained from an anonymous questionnaire between September 2017 to January 2018 in three cities in China, and contained questions about sexual-related behaviors and CSA experience. Latent class analysis (LCA) was used to classify the patterns of sexual behaviors and binomial regression was used to examine the relationships among these variables. Results Among 628 MSM, 22.6% reported experiencing CSA. A two-classes pattern of sexual behaviors was identified, with 46.7% in the low-risk class and 53.3% in the high-risk class. MSM who experienced CSA were more likely to be high-risk group compared to those without CSA experiences [odds ratio (OR) = 1.981; 95% confidence interval (CI) =1.329–2.954)]. Conclusions CSA was prevalent among Chinese MSM. And MSM with CSA experiences are more prone to be assigned to the high-risk group. Future HIV interventions need to focus on MSM who experienced CSA.

Purpose. To evaluate two different approaches of anterior vitrectomy combined with hyaloidotomy, zonulectomy, and iridectomy (VHZI) for fluid misdirection syndrome (FMS) secondary to phacoemulsification with intraocular lens implantation combined with goniosynechialysis (phaco-IOL-GSL). Methods. Nine patients with FMS who developed after a phaco-IOL-GSL procedure, were retrospectively studied from May 2015 to February 2018. They were treated with VHZI, in which 5 cases underwent local anterior vitrectomy via anterior chamber approach, and the others underwent comprehensive vitrectomy via pars plana approach. Main outcome measures were pre- and postoperative intraocular pressure (IOP), number of antiglaucoma medications, and relapse rate. Results. Incidence of FMS secondary to phaco-IOL-GSL was 1.4% (9 in 652 eyes), which was promptly resolved in all affected cases. VHZI via anterior chamber approach resulted in a significant decrease in the mean IOP from 40.2 ± 9.7 mm Hg at presentation to 15.2 ± 4.8 mm Hg postoperatively (P=0.01). The median number of antiglaucoma medications reduced from 3 to 2 (P=0.066). Meanwhile, VHZI via pars plana approach also resulted in the reduction of the mean IOP values from 26.0 ± 5.7 mm Hg at presentation to 15.2 ± 3.3 mm Hg postoperatively (P=0.092). The median number of antiglaucoma medications also reduced from 3.5 to 1.5 (P=0.059). Relapse rate of the treatment through pars plana approach (0%, 0/4) was much lower than that through anterior chamber approach (40%, 2/5), although the difference was not statistically significant (P=0.444). Conclusions. FMS is a rare but severe complication secondary to phaco-IOL-GSL. Compared to VHZI with local anterior vitrectomy via anterior chamber approach, VHZI with comprehensive anterior vitrectomy via pars plana approach might be a more effective procedure to treat FMS. The study has been registered in Contact ClinicalTrials.gov PRS Identifier: NCT04172857.

Cellulosic conductive paper/film reinforced by graphene is a promising substrate for energy storage applications due to its comparable conductivity, great flexibility and low cost. However, how to balance the content ratio of graphene/cellulose well is still a challenge. Because conductive paper of low graphene content usually has poor electrical property, while high graphene content is also discouraged owing to the decrease in other properties though electrically improved. Based on this, we developed a different method to produce the graphene/cellulose composite conductive paper. Instead of a separate intermediate-fabrication, starting materials here are continuously one-pot processed, in prior to casting the intermediate paper (solid phase). Next, it is reduced by the l-ascorbic acid solution (liquid phase), followed by a filtration to give the hetero-reduced conductive paper (HRCP). Our results indicate that HRCP possesses high conductivity up to 376 ± 4 S/m, along with good thermal and dynamic behaviors, at a relatively low graphene content of 20 wt%. Therefore, HRCP is expected to be utilized in the field of emerging energy storage.

Two lignin-containing cellulose nanofibril (LCNF) samples, produced from two unbleached kraft pulps with very different lignin contents, were used to produce reinforced polyvinyl alcohol (PVA) hydrogels. The effects of LCNF loading (0.25–2 wt %) and lignin content on the rheological and mechanical properties of the reinforced hydrogels were investigated. The 2 wt % LCNF-reinforced PVA hydrogels exhibited up to a 17-fold increase in storage modulus and a 4-fold increase in specific Young’s modulus over that of pure PVA hydrogel. Both the mechanical and rheological properties of LCNF-reinforced PVA hydrogels can be tuned by varying LCNF loading and LCNF lignin content. During LCNF production, lignin reduced cellulose depolymerization, resulting in LCNF with high aspect ratios that promoted entanglement and physical bridging of the hydrogel network. Free lignin particles generated during LCNF production acted as multifunctional nanospacers that increased porosity of the hydrogels. Because LCNFs were produced...

High lignin-containing cellulose nanocrystals (HLCNCs) were successfully isolated from hydrothermally treated aspen fibers and freeze-dried and compounded with poly (lactic acid) (PLA) by extrusion and injection molding. As a comparison, PLA composites containing commercial lignin-coated CNCs (BLCNCs) were also produced. HLCNCs showed higher crystallinity, larger surface area, lower degree of agglomeration, and more hydrophobic surfaces compared to BLCNCs, as characterized by electron microscopy, surface area measurements, thermal analysis, spectroscopy and water contact angle measurements. The effect of lignin and CNC morphology on the mechanical, thermal and viscoelastic properties and CNCs/polymer interfacial adhesion of nanocomposites was investigated with tensile test, DSC and DMA. Compared to neat PLA, the Young's modulus, elongation to break, and toughness of PLA/2%HLCNCs were improved by 14, 77, and 30%, respectively. HLCNCs and BLCNCs act as nucleating fillers, increasing the degree of crystallinity (χc) of PLA in nanocomposites. The presence of lignin nanoparticles in the HLCNC increased the compatibility/adhesion between CNCs and polymer matrix which increased the storage modulus.

Plant-derived cellulose nanofibrils (CNFs) have shown reinforcing effects in polymer nanocomposites. However, freeze-dried CNFs are foam-like material, namely aerogel, that are challenging to disperse in a polymer matrix. In this work, a liquid infusion process was developed for a CNF/epoxy nanocomposite cross-linked foam structure with alterable properties without damaging the foam structure. Microstructures of CNF/epoxy composite foams with different formulations were evaluated using a scanning electron microscope. Surface morphology showed that the CNF cross-linked fibers were well attached by epoxy resin. All absolute and specific mechanical properties [by normalizing the measured parameters against the measured density (ρ)] were investigated. Water resistance and thermal stability of CNF/epoxy composite foams were investigated by water absorption test and thermogravimetric analysis. The concentration of epoxy solution in both tetrahydrofuran (THF) solvents and ethyl acetate (EA) solvents was shown to improve compressive properties and water resistance. The samples fabricated with higher epoxy concentration had higher compressive properties, better water resistance, and better thermal stability. The CNF/epoxy composite foams exhibited compressive modulus and compressive strength up to 175 and 10 MPa, respectively. The water diffusion coefficient of CNF/epoxy composite foams was reduced with an increase in epoxy loading. Further, the CNF/epoxy nanocomposite foams fabricated by the epoxy/THF solution had a more uniform structure and better strength performance than foams fabricated by the epoxy/EA solution, due to the increased solubility of the epoxy in THF compared to epoxy in EA. The glass transition temperature (Tg) was determined by differential scanning calorimetry. The Tg of the nanocomposites was influenced by the CNF/epoxy composition. Therefore, the properties of CNF/epoxy nanocomposite foams can be optimized via changing the solvent and concentration of epoxy resin in solvent.

Space-borne hyperspectral imagery is an important tool for earth sciences and industrial applications. Higher spatial and spectral resolutions have been sought persistently, although this results in more power, larger volume and weight during a space-borne spectral imager design. For miniaturization of hyperspectral imager and optimization of spectral splitting methods, several methods are compared in this paper. Spectral time delay integration (TDI) method with high transmittance Integrated Stepwise Filter (ISF) is proposed.With the method, an ISF imaging spectrometer with TDI could achieve higher system sensitivity than the traditional prism/grating imaging spectrometer. In addition, the ISF imaging spectrometer performs well in suppressing infrared background radiation produced by instrument. A compact shortwave infrared (SWIR) hyperspectral imager prototype based on HgCdTe covering the spectral range of 2.0–2.5 μm with 6 TDI stages was designed and integrated. To investigate the performance of ISF spectrometer, a method to derive the optimal blocking band curve of the ISF is introduced, along with known error characteristics. To assess spectral performance of the ISF system, a new spectral calibration based on blackbody radiation with temperature scanning is proposed. The results of the imaging experiment showed the merits of ISF. ISF has great application prospects in the field of high sensitivity and high resolution space-borne hyperspectral imagery.

This study investigated the production of crude bio-oils from three laboratory cultivated and two commercial grade algal biomass sources via hydrothermal liquefaction (HTL) process. Results demonstrated the crude bio-oils generated from laboratory cultivated algae fed 5% anaerobic digestion effluent as sole nutrient source have similar thermochemical characteristics as comparison with that of derived from commercial algae. The HTL conditions were optimized (300°C for 20 min) and the generated bio-oils were characterized by gas chromatography mass spectrometry, Fourier transform infrared spectroscopy, and electrospray ionization-mass spectrometry analyses and simulated distillation by thermogravimetric analysis. The bio-oil yields were between 28 and 41%. The bio-oils were mainly comprised of fatty acids and alkanes. These bio-oils can be further upgraded and refined into value added transportation fuels and chemicals. © 2017 American Institute of Chemical Engineers Environ Prog, 2017

Solid acids have been proposed as a hydrolytic agent for wood biomass dissolution. In this work, we presented an environmentally friendly physicochemical treatment to leave behind cellulose, dissolve hemicellulose, and remove lignin from poplar wood. Several pretreatments, such as autohydrolysis and disk refining, were compared to optimize and modify the process. The p-toluenesulfonic acid could extract lignin from wood with a small amount of cellulose degradation. Disk refining with subsequent acid hydrolysis (so-called physicochemical treatment) doubled the delignification efficiency. A comprehensive morphology and overall chemical composition were provided. The crystallinity index (CrI) of treated poplar was increased and the chemical structure was changed after physicochemical treatment. Optical microscopy and scanning electron microscopy analysis demonstrated physicochemical treatment affected the morphology of poplar wood by removing lignin and generating fiberization. In general, this work demonstrated this physicochemical method could be a promising fractionation technology for lignocellulosic biomass due to its advantages, such as good selectivity, in removing lignin while preserving cellulose.

Circular RNAs (circRNAs), characteristic of covalently closed loops generated by back-splicing, are a subclass of single-stranded RNA molecules. Owing to the circular structures, circRNAs are protected from exonuclease-induced degradation, which makes them more stable compared with linear RNAs. With the development of high-throughput sequencing technology and bioinformatics, the roles of circRNAs in a variety of physiological and pathophysiological processes have been increasingly revealed. Although the functions of most circRNAs remain largely elusive, accumulating studies have identified them as microRNA(miRNA) sponges, protein regulators, transcriptional regulators, protein templates, and so forth. In this review, we briefly describe the biogenesis of circRNAs and provide an overview on their functions in cancers, including miRNA sponges, protein regulators, transcriptional regulators, protein templates. Furthermore, we discuss the potential application of circRNAs as biomarkers and give insight into future perspectives.

CircRNAs are reported to exert a significant role in modulating genes in cancers, including osteosarcoma progression. Up to now, the function of circ_0010220 in osteosarcoma is still poorly known. The aim of our work was to figure out the potential mechanism of circ_0010220/miR-503-5p/CDCA4 axis in osteosarcoma progression. Firstly, quantitative RT-qPCR was utilized to measure the expression of circ_0010220 in osteosarcoma cells. Then, osteosarcoma cell proliferation, apoptosis, cell cycle, migration and invasion after loss of circ_0010220 were evaluated using CCK-8, flow cytometry, transwell migration, invasion and tumorigenesis experiments respectively. Circ_0010220 expression was markedly increased in osteosarcoma cells. Additionally, knockdown of circ_0010220 significantly depressed tumor growth. CCK-8 analysis indicated that down-regulation of circ_0010220 inhibited osteosarcoma cells proliferation. Flow cytometry assay showed that knockdown of circ_0010220 induced cell apoptosis and blocked cell cycle in the G1 phase. Meanwhile, cell migration an invasion was reduced by circ_0010220. Furthermore, miR-503-5p was predicted as the target for circ_0010220 and miR-503-5p inhibitors reversed cell growth suppressed through silencing circ_0010220. Then, our study demonstrated that Cell Division Cycle-Associated protein 4 (CDCA4) could be a downstream target of miR-503-5p. Additionally, circ_0010220 down-regulation reduced CDCA4 expression level and the inhibitors of miR-503-5p reversed that. In conclusion, we indicated circ_0010220 can be an important biomarker for osteosarcoma via regulating miR-503-5p and CDCA4.

The effect of accelerated weathering exposure time on the bioplastic, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was studied. The chemical structure and thermophysical property changes of solvent cast PHBV films were examined by a combination of optical microscopy, size exclusion chromatography, FTIR and 1H NMR spectroscopies, tensile testing, and differential scanning calorimetry (DSC). The exposed PHBV surfaces experienced surface crazing upon weathering. The molar mass of weathered PHBV was shown to decrease due to chain scission which was dominant over the crosslinking reaction mechanism, and compositional analysis showed the polymer degradation was non-random between the hydroxybutyrate-hydroxyvalerate units. The degree of crystallinity for PHBV was shown to increase significantly (by about 20%) upon weathering. Tensile tests showed that the weathered PHBV exhibited reduced ultimate strength and elongation to break, while the Young's modulus increased ascribing to an increase in crystallinity. Different degradation mechanisms (Norrish I/II, radical initiation, crosslinking, and hydrolysis) of PHBV are proposed and confirmed based on the experimental findings. This study provides degradation insight for PHBV exposed to both UV radiation and moisture.

Aims: To identify extractable components in the traditional medicinal plant, Bryophyllum pinnatum (BP). Methodology: The leaves of BP were sequentially extracted with non-polar (CH2Cl2) and polar (CH3OH) solvents. The extracts were derivatized to their volatile fatty acid methyl esters (FAME) and trimethylsilyl (TMS) esters/ethers and characterized by gas chromatography mass spectrometry (GC-MS). Results: GC-MS analysis revealed the presence of sterols, fatty acids, monoarylphenolics, sugars, alcohols, sugar alcohols, sugar acids, carboxylic acids, dicarboxylic acids, tricarboxylic acids, vitamin, alkanes and alkenes. Conclusion: Compounds identified (e.g. tocopherol) in the extracts are most likely responsible for its antimicrobial, antifungal, anticancer, antitumour and insecticidal activities. Original Research Article Faboro et al.; EJMP, 14(3): 1-10, 2016; Article no.EJMP.26156 2

Polyhydroxyalkanoate (PHA) production generates a significant amount of residual bacterial biomass (RBB) after PHA extraction. The RBB as a zero-value waste contains proteins, carbohydrates, phenolics, and ash, which can be managed and converted to bio-oil and biochar products by pyrolysis. Thermogravimetric analysis (TGA) was used to investigate the thermodegradation kinetics of RBB and pyrolysis–GCMS studies were employed to determine potential chemical products. Pyrolysis was conducted on a laboratory-scale auger reactor at 500 °C. The bio-oil and biochar yield were 28 and 46%, respectively. The pyrolysis bio-oil was characterized by the combination of GCMS, high-pressure liquid chromatography (HPLC), and electrospray ionization mass spectrometry (ESI–MS). The bio-oil was dominated by nitrogen-containing, hydrocarbons, and aromatic compounds. The biochar was studied for its specific surface area and pore size, chemical functionality by Fourier transform infrared (FTIR) and Raman spectroscopies, and butane absorption activity. Biochar was comprised of a large part of polycondensed phenolic and majorly disordered amorphous carbon.

A smectic main-chain liquid crystalline elastomer (LCE), with controlled shape memory behavior, is synthesized by polymerizing a biphenyl-based epoxy monomer with an aliphatic carboxylic acid curing agent. Microstructures of the LCEs, including their liquid crystallinity and cross-linking density, are modified by adjusting the stoichiometric ratio of the reactants to tailor the thermomechanical properties and shape memory behavior of the material. Thermal and liquid crystalline properties of the LCEs, characterized using differential scanning calorimetry and dynamic mechanical analysis, and structural analysis, performed using small-angle and wide-angle X-ray scattering, show that liquid crystallinity, cross-linking density, and network rigidity are strongly affected by the stoichiometry of the curing reaction. With appropriate structural modifications it is possible to tune the thermal, dynamic mechanical, and thermomechanical properties as well as the shape memory and thermal degradation behavior of LCEs.

In this study, α-cellulose fibers reinforced green biocomposites based on polyhydroxybutyrate (PHB) and the copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were prepared and characterized. The α-cellulose fibers were isolated from at-risk intermountain lodgepole pine wood by successive removal of extractives, lignin and hemicellulose. Grafting of PHB or PHBV onto cellulose was conducted using reactive extrusion with dicumyl peroxide free radical initiation at high temperature. It is postulated that the grafted copolymers at the interfaces of cellulose and the polymer matrix performed as an interfacial coupling agent. Grafting tended to interact with both the hydrophilic fibers and the hydrophobic PHB or PHBV matrix. The biocomposites were characterized by scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA) and indicated good interfacial bonding and compatibility between the two phases. The mechanical properties of the biocomposites were improved by grafting due to improved stress transfer between the two interphases of the fiber/polymer matrix as compared to the blend control composite. The crystallinity of PHB, PHBV and cellulose in the biocomposite were reduced as determined by Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC) analyses. This in situ reactive extrusion process offers an effective approach to improve the properties of biocomposite materials from sustainable resources.

Wood-based mesoporous activated carbon fibers (C-WACF) were prepared using wood charcoal (WC) as an additive. C-WACF with different WC contents (0, 0.5, 1, 1.5, 2 and 2.5 %) was characterized by N2 adsorption, SEM, XRD, and XPS. With more WC added, the BET specific surface area and total volume of C-WACF showed upsurge and reached a maxima at WC = 1 %, when WC > 1 % a diminishing trend was seen. The mesoporosity of C-WACF reached 45 % when the WC content was 1 %. C-WACF reserved the characteristic peak of WC by XRD. With a WC content increase, the d002 and La of C-WACF were seen to decrease and then increase; Lc and Lc/d002 first increased and then decreased. XPS showed more C–C and C–OOH groups transformed to C–OH and C=O groups on the surface of C-WACF with higher WC loading. The introduction of 1 % WC was proved to be appropriate for making Wood-based mesopores ACF.

Cellulose nanocrystals (CNCs), produced from dissolving wood pulp, were chemically functionalized by transesterification with canola oil fatty acid methyl ester (CME). CME performs as both the reaction reagent and solvent. Transesterified CNC (CNCFE) was characterized for their chemical structure, morphology, crystalline structure, thermal stability, and hydrophobicity. Analysis by Fourier transform infrared (FTIR) and FT-Raman spectroscopies showed that the long chain hydrocarbon structure was successfully grafted onto CNC surfaces. After transesterification the crystal size and crystallinity of nanocrystals were not changed as determined by Raman spectroscopy and wide angle X-ray diffraction (XRD). CNCFE showed higher thermal stability and smaller particle size than unmodified CNCs. Water contact angle measurement indicated the CNCFE surface has significantly higher hydrophobicity than unmodified CNCs. The transesterified CNCs could be potentially used as hydrophobic coatings and reinforcing agents to hydrophobic polymer for nanocomposites.

Bio-oil and bio-char were produced from potato peel waste (PPW) and PPW fermentation residue (PPW-FR) using a laboratory-scale auger pyrolyzer at 450 °C. Proximate and ultimate analyses of the feedstock materials PPW and PPW-FR were determined. The bio-oils were fractionated and analyzed by gas chromatography mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), and electrospray ionization mass spectrometry (ESI-MS). The bio-chars were characterized by Fourier transform infrared spectroscopy (FTIR) and butane activity (BA) measurement. The PPW and PPW-FR bio-oils had a relatively high level of lipid and suberin-derived compounds as compared with hybrid poplar (HP) pyrolysis bio-oil. The BA measurement also suggested that PPW and PPW-FR bio-chars have better adsorption performances than HP bio-char.

Residues high in lignin and ash generated from the simultaneous saccharification and fermentation of corn stover were thermally pretreated in an inert (N2) atmosphere to study the effect of time and temperature on their softening points. These residues are difficult to feed into gasifiers due to premature thermal degradation and formation of reactive liquids in the feed lines, leading to plugging. The untreated and treated residues were characterized by proximate and ultimate analysis, and then analyzed via TGA, DSC, 13C NMR, Py-GC–MS, CHNO/S, and TMA. Interpretation of the compositional analysis indicates that the weight loss observed during pretreatment is mainly due to the thermal decomposition and volatilization of the hemicelluloses and amorphous cellulose fractions. Fixed carbon increases in the pretreated material, mostly due to a concentration effect rather than the formation of new extra poly-aromatic material. The optimal processing time and temperature to minimize the production of carbonyl groups in the pretreated samples was 300 °C at a time of 30 min. Results showed that the softening point of the material could be increased from 187 °C to 250 °C, and that under the experimental conditions studied, pretreatment temperature plays a more important role than time. The increase in softening point was mainly due to the formation of covalent bonds in the lignin structures and the removal of low molecular weight volatile intermediates.

Poplar wood fibers were chemically modified by esterification (acetate, propionate, benzoate) and then compounded with high density polyethylene (HDPE) into wood plastic composites (WPC). The esterified fibers were characterized (spectroscopy, TGA and contact angle) and shown to be more thermally stable and hydrophobic than unmodified fibers. The WPC were characterized for their mechanical and rheological properties, adhesion factor, water resistance, accelerated weathering and biodurability performance. Color change, surface morphology and extent of oxidation on the surface of weathered WPC were monitored using colorimetry, microscopy and FTIR spectroscopy, respectively. Benzoylated fiber based WPC experienced the least surface crazing and color change due to weathering. Esterification of fibers significantly reduced weight losses in the resulting WPC when it was exposed to brown-rot and white-rot fungi as compared to unmodified fiber WPC. Esterification of wood fibers resulted in more biodurable and photostable WPC.

Short Wave InfraRed(SWIR) spectral imager is good at detecting difference between materials and penetrating fog and mist. High spectral resolution SWIR hyperspectral imager plays a key role in developing earth observing technology. Hyperspectral data cube can help band selections that is very important for multispectral imager design. Up to now, the spectral resolution of many SWIR hyperspectral imagers is about 10nm. A high sensitivity airborne SWIR hyperspectral imager with narrower spectral band will be presented. The system consists of TMA telescope, slit, spectrometer with planar blazed grating and high sensitivity MCT FPA. The spectral sampling interval is about 3nm. The IFOV is 0.5mrad. To eliminate the influence of the thermal background, a cold shield is designed in the dewar. The pixel number of spatial dimension is 640. Performance measurement in laboratory and image analysis for flight test will also be presented.

Space-borne hyperspectral imager is capable of providing large amount of image data with high spatial and spectral resolution. However, with the increase of the resolution, the volume and weight of conventional dispersive (prism/grating) imaging spectrometers also increase significantly. Meanwhile, the demand for the system sensitivity becomes even higher. In this paper, the application of Integrated Stepwise Filter (ISF) in infrared hyperspectral imaging technology was analyzed, including optical efficiency, instrumental background radiation suppression, spectral time delay integration (TDI) and other performances. Several methods which can enhance the system sensitivity were also provided. A compact short-wave infrared (SWIR) hyperspectral imager prototype covering the spectral range of 2.0μm-2.5μm with 6 TDI stages was designed and implemented. The results of the imaging experiment demonstrated that ISF has great application prospects in the field of high sensitivity space-borne hyperspectral imagery.