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As an indispensable part of large Computer Numerical Control machine tool, rolling bearing faults diagnosis is particularly important. However, due to the imbalanced distribution and partially missing of collected monitoring data, such diagnostic issue generally emerging in manufacturing industry is still hardly to be solved. Thus, a multilevel recovery diagnosis model for rolling bearing faults from imbalanced and partially missing monitoring data is formulated in this paper. Firstly, a regulable resampling plan is designed to handle the imbalanced distribution of data. Secondly, a multilevel recovery scheme is formed to deal with partially missing. Thirdly, an improved sparse autoencoder based multilevel recovery diagnosis model is built to identify the health status of rolling bearings. Finally, the diagnostic performance of the designed model is verified by artificial faults and practical faults tests, respectively.

We developed a surface functionalization-enhanced CD based MEG device method via modifying a strong ionizing organic acid on a CD surface.

Background: Many patients in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) had a significant improvement (> 10%) in the left ventricular ejection fraction (LVEF) during the course of the study, but the factors and outcomes associated with such improvement are uncertain. Methods: We examined factors and rates of mortality, cause-specific mortality, and implantable cardioverter defibrillator (ICD) shocks associated with improvement in LVEF by analyzing patients in the SCD-HeFT who were randomized to placebo or an ICD and who had an LVEF checked during follow-up. Results: During a median follow-up of 3.99 years, of 837 patients who had at least two follow-up LVEF measurements, 276 (33%) patients had > 10% improvement in LVEF and 561 (67%) patients had no significant change in LVEF. Factors significantly associated with LVEF improvement included female sex, white race, history of hypertension, a QRS duration < 120 ms, and beta-blocker use. Improvement in LVEF was associated with a significant improvement in survival. There was no significant association between improvement in LVEF and cause-specific death, but there was a significant association between improvement in LVEF and reduced risk of receiving appropriate ICD shocks. Conclusions: About a third of patients in this analysis, who were randomized to placebo or an ICD in SCD-HeFT, had a significant improvement in LVEF during follow-up; improvement in LVEF was associated with improved survival but not with cause-specific death, and with decreased likelihood of receiving appropriate ICD shocks.

The widespread testing for severe acute respiratory syndrome coronavirus 2 infection has facilitated the use of test-negative designs (TNDs) for modeling coronavirus disease 2019 (COVID-19) vaccination and outcomes. Despite the comprehensive literature on TND, the use of TND in COVID-19 studies is relatively new and calls for robust design and analysis to adapt to a rapidly changing and dynamically evolving pandemic and to account for changes in testing and reporting practices. In this commentary, we aim to draw the attention of researchers to COVID-specific challenges in using TND as we are analyzing data amassed over more than two years of the pandemic. We first review when and why TND works and general challenges in TND studies presented in the literature. We then discuss COVID-specific challenges which have not received adequate acknowledgment but may add to the risk of invalid conclusions in TND studies of COVID-19.

Pancreatic cancer remains one of the most lethal malignancies worldwide. The combination of the first-line standard agent gemcitabine (GEM) with the molecular-targeted drug erlotinib (Er) has emerged as a promising strategy for pancreatic cancer treatment. However, the clinical benefit from this combination is still far from satisfactory due to the unfavorable drug antagonism and the fibrotic tumor microenvironment. Herein, we propose a membrane-camouflaged dual stimuli-responsive delivery system for the co-delivery of GEM and Er into pancreatic cancer cells and tissues to block the antagonism, as well as reshapes profibrotic tumor microenvironment

The spatter formation process was observed by high-speed imaging during the full-penetration laser welding (FPLW) process of 4 mm-thick TC4 alloy plates. The effects of process parameters on spatter formation were studied. The results showed that the process parameters have obvious effects on the fluid flow characteristics in the melt pool and the dynamic behaviors of metal vapor in the keyhole, which and then affects the spatter behaviors. When using low-power and low-speed parameters, the fluid flow in the melt pool is unstable. When the melt flow impacts the keyhole, the keyhole opening diameter shrinks instantly, resulting in an immediate increase in the metal vapor eruption velocity at the keyhole opening and leading to the formation of weld spatter with a small size and high flying speed. When using high-power and high-speed parameters, a large amount of metal vapor erupts at high velocity from the keyhole opening transiently, resulting in the formation of a higher liquid column on the keyhole wall. The liquid column fractures to form weld spatter with a large size and low flying speed. When the pressure of the metal vapor in the keyhole is too large, the surface tension of the liquid metal under the keyhole cannot withstand it, causing an explosion on the backside of the melt pool. During the explosion, a large amount of spatter and plasma is ejected from the keyhole exit, and the plasma plume above the melt pool is weakened.

Fatty acid profile was one of the important characteristic parameters of edible oil. With the intensification of interest in microalgae as a potential source of edible oil, rapid methods are needed to determine the fatty acid composition of microalgae. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) was applied to determine the lipid and fatty acid contents of Nannochloropsis oceanica, a species rich in eicosapentaenoic acid. Samples with different intracellular components were obtained by setting different culture conditions (light intensity and nitrogen concentration). In the spectra of FTIR, some characteristic bands for lipids (3025–2800 cm−1, 1770–1710 cm−1, 1480–1350 cm−1) were identified. Partial least square regression (PLSR) models were developed to predict total biomass, lipid contents, and main fatty acid contents (palmitic acid C16:0, palmitoleic acid C16:1, eicosatetraenoic acid C20:4, eicosapentaenoic acid C20:5). Generally, the prediction ability of the model established with full spectra was slightly better than that of the model established with specific bands. In the optimized model, excellent coefficients of determination (R2 ≥ 0.90), both for calibration and prediction, were found for all variables, except for fatty acid C20:4, which was slightly worse (R2 = 0.8797). The pretreatment methods of samples were further studied. It was found that the acid-heating method (0.1 M HCl, 100 °C, 0.5 h) effectively reduced the interference of the carbohydrate in samples, thus improving the measurement of the characteristic fatty acids C20:4 and C20:5 of N. oceanica. This study showed the feasibility of FTIR as a rapid screening method for evaluating biomass and lipid content, especially some special fatty acid profile of microalgae.

Cable Deployed Electrical Submersible Pumping (CDESP) System is a new generation of Rigless ESP technology, it utilizes the specialized cable for ESP changeout, which will save rig cost and reduce field operation time significantly.Cable deployed conventional ESP system is a game-changing technology in the Rigless ESP industry, which makes the CDESP compatibility possibleby using conventional ESP instead of inverted ESP assembly. However, reliability is always the main concern of clients, especially when it fails to retrieve ESP assembly by the specialized cable, a rig will have to be neededto carry out the ESP replacement jobs. This paper will introduce the design philosophy and installation procedure of Rigless Cable Deployed Conventional ESP System to demonstrate how to ensure the reliability and robustness. In addition, emergency fishing design is proposed to pull out from weak point in case of failing to retrieve ESPby cable and fully eliminate the rigs inESP replacement-jobs.

Neuroblastoma (NB) is an extracranial solid tumor in children with poor prognosis in high-risk patients and its pathogenesis and prognostic markers urgently need to be explored. This study aimed to explore potential biomarkers related to NB from the aspect of lipid metabolism. Fifty-eight lipid metabolism-related differentially expressed genes between high-risk NB and non-high-risk NB in the GSE49710 dataset were analyzed using bioinformatics, including 45 down-regulated genes and 13 up-regulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified steroid hormone biosynthesis as an abnormal metabolic pathway in high-risk NB. Survival analysis established a three-gene prognostic model, including ACHE, GDPD5 and PIK3R1. In the test data, the AUCs of the established prognostic models used to predict patient survival at 1, 3 and 5 years were 0.84, 0.90 and 0.91, respectively. Finally, in the SH-SY5Y cell line, it was verified that overexpression of GDPD5 can inhibit cell proliferation and migration, as well as affect the lipid metabolism of SH-SY5Y, but not the sugar metabolism. hsa-miR-592 was predicted to be a potential target miRNA of GDPD5 by bioinformatics. In conclusion, this study develops a lipid-metabolism-related gene-based prognostic model for NB and demonstrates that GDPD5 inhibits SH-SY5Y proliferation and migration and may be targeted by hsa-miR-592 and inhibit SH-SY5Y fat synthesis.

A new generation of Rigless ESP technology, Cable Deployed ESP (CDESP) System uses specialized cable to replace ESP, which saves rig cost and reduces production deferment tremendously. However, most CDESP in the market are applied with inverted ESP assembly, which has high requirements and more uncertainties on customized ESP. This paper will introduce the design philosophy of a CDESP applied with conventional ESP assembly, which is more compatible. Rounds of multiple factory tests were successful, pressure test of hanger assembly and penetrator system were up to 7,500 psi,cable connector tension tests meet the specialized cable and ESP weight requirement. Also, the electrical tests were qualified. The factory tests and field applications verified the reliability and robustness of this new generation of Rigless ESP technology.

The positioning accuracy of Ziyuan-3 01 (ZY-3 01) and Gaofen-7 (GF-7) panchromatic imagery, obtained during the early deployment of the satellites, was verified. Particularly, this paper first vali...

Nowadays, artificial construction of bacteria-algae consortia to enhance microalgal biomass is prevalent in enclosed systems, while few are built in an open culture. In this study, Achromobacter sp. and Rhizobium sp., isolated from an open pond of Chlorella sorokiniana, were the microalgal growth-promotion bacteria and selected to build the bacteria-algae consortia with axenic C. sorokiniana in open cultivation systems. To examine the performance of these two artificial bacteria-algae consortia in open culture under stable cultivation conditions, the co-cultivation experiments were conducted under constant temperature and light intensity indoors. It was found that Achromobacter sp. gradually lost the dominance of the population in the co-culture and failed to promote the growth of C. sorokiniana during open cultivation. However, the Rhizobium sp. maintained its dominant population of bacterial community in open culture and could promote the growth of C. sorokiniana, with an enhancement of 13.76%. To further evaluate the effects of Rhizobium sp. on microalgae under variations of temperature and sunlight intensity conditions, the open co-cultivation experiments were built outdoors. Results showed that the growth of C. sorokiniana could rise 13.29% only when Rhizobium sp. was added to the culture continuously, and addition of bacterial solution in log-phase of microalgae could help Rhizobium sp. dominate in the bacterial community. In this way, addition of Rhizobium sp. in the log-phase of C. sorokiniana should be an effective process to be applied to open ponds cultivation. Our findings are a step toward applying growth-promotion bacteria for C. sorokiniana for applications in open cultivation systems.

Mechano-luminescent materials that exhibit distinct luminescence responses to force stimuli are urgently anticipated in view of application needs in the fields of sensing, anti-counterfeiting, optoelectronic devices, etc. However, most of the reported materials normally exhibit force-induced changes in luminescent intensity, whereas materials that possess force-induced color-variable luminescence remain rarely reported. Herein, for the first time, a novel mechanical force-induced color-variable luminescence material from carbon dots (CDs) in boric acid (CD@BA) is reported. At low CDs concentration, the luminescence of CD@BA exhibits a grinding-induced color variable from white to blue. This grinding-induced color variable can be switched to yellow-to-white changing by increasing the CDs concentration in BA. The grinding-induced color-variable luminescence originates from dynamic variation in emission ratio of fluorescence and room temperature phosphorescence, due to the influence of oxygen and water vapor in the air. At high CDs concentration, short-wavelength fluorescence undergoes more severe reabsorption compared to room temperature phosphorescence, leading to grinding-induced color-variable switching from white-to-blue to yellow-to-white. Based on the unique properties of CD@BA powder, the applications of recognizing and visualizing fingerprints on the surfaces of various of materials are demonstrated.

White-light-emitting carbon dots (CDs) with fluorescence/phosphorescence dual-emission features are of great importance for single-phase white-light-emitting diodes (WLEDs), but so far rather limited due to weak phosphorescence. Herein, a highly efficient white-light emissive CD-based material is developed by one-step heat treatment of lycorine hydrochloride and boric acid (BA). The prepared CD@BA powders show prominent fluorescence/phosphorescence dual-emission with extraordinarily high overall quantum yield (QY) of 46%, phosphorescence QY of 30% and a broad full width at half maximum over 180 nm. Doping of N and B atoms as well as the strong interaction between CDs and the BA matrix not only effectively prevents aggregation-induced quenching in the solid state, but also greatly promotes phosphorescence emission, leading to the emergence of an ultrabroad-band emission spectrum. Based on the unique dual-emissive performance of CD@BA powders, they are successfully applied to single-component WLEDs. This work provides a new strategy for mass production of efficient white-light emissive CD-based materials, which have promising applications for single-phase WLEDs.

PEG-interpenetrated dual-sensitive hydrogels that load nano lipid carrier (NLC) were researched and developed for topical drug administration. Natural antioxidant α-lipoic acid (ALA) was selected as our model drug. The α-lipoic acid (ALA) nano lipid carrier was successfully prepared by hot melt emulsification and ultrasonic dispersion method, and the physicochemical properties of the nano lipid carrier were investigated, including morphology, particle distribution, polydispersity coefficient, zeta potential and encapsulation efficiency. Carboxymethyl chitosan and poloxamer 407 contributed to pH- and temperature-sensitive properties in the hydrogel, respectively. Natural non-toxic cross-linking agent genipin reacted with carboxymethyl chitosan to form the hydrogel. Poly ethylene glycol (PEG), a polymer compound with good water solubility and biocompatibility, interpenetrated the hydrogel and influenced the mechanical strength and drug release behaviour. FI-IR test verified the successful synthesis of the hydrogel. The rheological parameters indicated that the mechanical strength of the hydrogel was positively correlated with the amount of PEG, and the in vitro dissolution profiles demonstrated that the increasement of PEG could accelerate the drug release rate. The compatibility of the drug delivery system was verified with cells and mice model. Topical delivery of ALA in solution, NLC and NLC-gel was investigated in-vitro.

Pancreatic cancer (PC) remains one of the most lethal human malignancies worldwide. Due to the insidious onset and the rapid progression, most patients with PC are diagnosed at an advanced stage rendering them inoperable. Despite the development of multiple promising chemotherapeutic agents as recommended first-line treatment for PC, the therapeutic efficacy is largely limited by unwanted drug resistance. Recent studies have identified exosomes as essential mediators of intercellular communications during the occurrence of drug resistance. Understanding the underlying molecular mechanisms and complex signaling pathways of exosome-mediated drug resistance will contribute to the improvement of the design of new oncologic therapy regimens. This review focuses on the intrinsic connections between the chemoresistance of PC cells and exosomes in the tumor microenvironment (TME).

The test-negative design (TND) has become a standard approach to evaluate vaccine effectiveness against the risk of acquiring infectious diseases in real-world settings, such as Influenza, Rotavirus, Dengue fever, and more recently COVID-19. In a TND study, individuals who experience symptoms and seek care are recruited and tested for the infectious disease which defines cases and controls. Despite TND's potential to reduce unobserved differences in healthcare seeking behavior (HSB) between vaccinated and unvaccinated subjects, it remains subject to various potential biases. First, residual confounding bias may remain due to unobserved HSB, occupation as healthcare worker, or previous infection history. Second, because selection into the TND sample is a common consequence of infection and HSB, collider stratification bias may exist when conditioning the analysis on testing, which further induces confounding by latent HSB. In this paper, we present a novel approach to identify and estimate vaccine effectiveness in the target population by carefully leveraging a pair of negative control exposure and outcome variables to account for potential hidden bias in TND studies. We illustrate our proposed method with extensive simulation and an application to study COVID-19 vaccine effectiveness using data from the University of Michigan Health System.

BackgroundLung adenocarcinoma (LUAD) is the most common respiratory globallywith a poor prognosis. Lipid metabolism is extremely important for the occurrence and development of cancer. However, the role of genes involved in lipid metabolism in LUAD development is unclear. We aimed to identify the abnormal lipid metabolism pathway of LUAD, construct a novel prognostic model of LUAD, and discover novel biomarkers involved in lipid metabolism in LUAD.MethodsBased on differentially expressed genes involved in lipid metabolism in LUAD samples from The Cancer Genome Atlas (TCGA), abnormal lipid metabolism pathways in LUAD were analyzed. The lasso penalized regression analysis was performed on the TCGA cohort (training set) to construct a risk score formula. The predictive ability of the risk score was validated in the Gene Expression Omnibus (GEO) dataset (validation set) using Kaplan-Meier analysis and ROC curves. Finally, based on CRISPR gene editing technology, hematopoietic prostaglandin D synthase (HPGDS) was knocked out in A549 cell lines, the changes in lipid metabolism-related markers were detected by western blotting, and the changes in cell migration were detected by transwell assay.ResultsBased on the differential genes between lung cancer tissue and normal tissue, we found that the arachidonic acid metabolism pathway is an abnormal lipid metabolism pathway in both lung adenocarcinoma and lung squamous cell carcinoma. Based on the sample information of TCGA and abnormally expressed lipid metabolism-related genes, a 9-gene prognostic risk score was successfully constructed and validated in the GEO dataset. Finally, we found that knockdown of HPGDS in A549 cell lines promoted lipid synthesis and is more invasive than in control cells. Rescue assays showed that ACSL1 knockdown reversed the pro-migration effects of HPGDS knockdown. The knockdown of HPGDS promoted migration response by upregulating the expression of the lipid metabolism key enzymes ACSL1 and ACC.ConclusionThe genes involved in lipid metabolism are associated with the occurrence and development of LUAD. HPGDS can be a therapeutic target of a potential lipid metabolism pathway in LUAD, and the therapeutic target of lipid metabolism genes in LUAD should be studied further.

Meta-analysis of 2 × 2 tables is common and useful in research topics including analysis of adverse events and survey research data. Fixed-effects inference typically centers on measures of association such as the Cochran-Mantel-Haenszel statistic or Woolf's estimator, but relies on assuming exact homogeneity across studies, which is often unrealistic. By showing that estimators of several widely-used methods have meaningful estimands even in the presence of heterogeneity, we derive improved confidence intervals for them under heterogeneity. These improvements over current methods are illustrated by simulation, and we also study which factors affect the coverage levels. We find that our confidence intervals provide coverage closer to the nominal level when heterogeneity is present, in both small and large-sample settings. The conventional confidence intervals derived under homogeneity are often conservative, though anti-conservative inferences occur in some scenarios. We also apply the proposed methods to a meta-analysis of 19 randomized clinical trials on the effect of sclerotherapy in preventing first bleeding for patients with cirrhosis and esophagogastric varices. Our methods provide a more interpretable approach to meta-analyzing binary data and more accuracy in characterizing the uncertainty of the estimators.

Amphoteric polymer can be used as retanning agent in leather manufacture. It is particularly useful in chrome-free tanning systems since it can regulate the charge properties of chrome-free leather and enhance the fixation of anionic post-tanning chemicals in leather. However, the aggregation and precipitation of amphoteric polymer retanning agents around the isoelectric point (pI) hinder their wide application. Herein, we synthesized five amphoteric acrylic polymers (AAPs) by free radical copolymerization with acrylic acid and five different cationic acrylic monomers. The effect of cationic monomer structure on the aggregation behavior of AAPs was investigated. The aggregation of AAPs in aqueous solution showed pH and concentration dependence. Light scattering analysis showed that Poly (AA-co-MAPTAC) and Poly (AA-co-DMAPMA) were in the shape of coiled linear flexible chains with small particle size (Rg 7.6 nm and 14.8 nm, respectively) near the pI. However, Poly (AA-co-DAC), Poly (AA-co-DMC) and Poly (AA-co-DMAEMA) were in the shape of hollow spheres and exhibited serious aggregation. Quantum chemical calculations suggested that the amide groups in the cationic monomers MAPTAC and DMAPMA enhanced the nucleophilicity of AAPs. Thus the corresponding AAPs could carry a large number of cationic charges to slow their aggregation when the pH just climbed over the pI. The results are expected to provide theoretical reference for the synthesis and widespread application of AAPs.

Semi-solid extrusion (SSE) 3D printing is an innovative and promising method that is suitable for the fabrication of personalized dosage forms of tablets. The aim of this study is to develop and evaluate the effectiveness of SSE 3D printed tablets with novel internal structures. Twelve types of 3D printed tablets with pre-designed structures were developed. Glipizide was selected as the model drug and three different concentrations of the HPMC K100LV polymer were used in the 3D printing process as the hydrophilic matrix. All of the printed tablets had satisfactory physical properties and structural integrity indicating the suitability of SSE 3D printing for the fabrication of personalized medicines with complex structures. The dissolution profiles of the printed tablets revealed the relationship between novel structures and drug release behavior. Tailored drug release may be easily achieved without changing the prescription by adjusting printing parameters such as outline value, grid width and printing pattern. All results of this paper clearly reveal the feasibility and capability of SSE 3D printing technology as a novel pharmaceutical manufacturing technique to fabricate personalized medicines and modulate drug dissolution profiles.

Full thickness cutaneous wound therapy and regeneration remains a critical challenge in clinical therapeutics. Recent reports have suggested that mesenchymal stem cells exosomes therapy is a promising technology with great potential to efficiently promote tissue regeneration. Multifunctional hydrogel composed of both synthetic materials and natural materials is an effective carrier for exosomes loading. Herein, we constructed a biodegradable, dual-sensitive hydrogel encapsulated human umbilical cord-mesenchymal stem cells (hUCMSCs) derived exosomes to facilitate wound healing and skin regeneration process. The materials characterization, exosomes identification, and in vivo full-thickness cutaneous wound healing effect of the hydrogels were performed and evaluated. The in vivo results demonstrated the exosomes loaded hydrogel had significantly improved wound closure, re-epithelialization rates, collagen deposition in the wound sites. More skin appendages were observed in exosomes loaded hydrogel treated wound, indicating the potential to achieve complete skin regeneration. This study provides a new access for complete cutaneous wound regeneration via a genipin crosslinked dual-sensitive hydrogel loading hUCMSCs derived exosomes.

Alpha-synuclein plays a vital role in the pathology of Parkinson's disease (PD). Spreading of α-synuclein in neighboring cells was believed to contribute to progression in PD. How α-synuclein transmission affects adjacent cells is not full elucidated. Here, we used recombinant α-synuclein to mimic intercellular transmitted α-synuclein in MES23.5 dopaminergic cells, to investigate whether and how it could modulate iron metabolism. The results showed that α-synuclein treatment up-regulated divalent metal transporter 1 (DMT1) and down-regulated iron transporter (FPN), also up-regulated iron regulatory protein 1 (IRP1) protein levels and hepcidin mRNA levels. Endocytosis inhibitor dynasore pretreatment completely abolished and even reversed the upregulation of DMT1 and IRP1 induced by α-synuclein, however, FPN down-regulation was partially blocked by dynasore. Autophagy-inducing agent rapamycin reversed DMT1 up-regulation and FPN down-regulation, and fully blocked the upregulation of IRP1. Elevated hepcidin levels induced by α-synuclein was fully blocked by dynasore pretreatment, however, even higher with rapamycin pretreatment. Alpha-synuclein treatment triggered endoplasmic reticulum (ER) stress. ER stress inducer thapsigargin induced similar responses elicited by α-synuclein. ER stress inhibitor salubrinal blocked the up-regulation of IRP1 and hepcidin, as well as DMT1 up-regulation and FPN down-regulation, also dramatically abolished cAMP-response elements binding protein phosphorylation induced by α-synuclein. Taken together, these finding indicated that extracellular α-synuclein could regulate cellular iron metabolism, probably mediated by ER stress. It provides novel evidence to elucidate the relationships between transmitted α-synuclein and iron metabolism disturbance in PD.

BackgroundAs an emerging therapy with a promising efficacy, immunotherapy has been widely used in the treatment of solid tumors and hematologic malignancies. This clinical study compares the efficacy of tislelizumab, a domestic immune checkpoint inhibitor (ICI), to that of sorafenib when used as a first-line therapeutic option in hepatocellular carcinoma (HCC), and the concurrence of HCC and non-Hodgkin’s lymphoma (NHL) is rare, especially in the treatment of ICIs.Case presentationA 61-year-old patient presenting with primary HCC and indolent B-cell lymphoma had a partial clinical response to tislelizumab for his primary HCC. Besides, we described a phenomenon of pseudo-progression and delayed diagnosis of his lymphoma during a long course of treatment.ConclusionTislelizumab, an immunotherapeutic option with a favorable efficacy and toxicity, can be used to manage double primary tumors. However, studies should aim to elucidate the probable mechanisms of this therapy. Pseudo-progression and separation remission make the treatment of double primary tumors even more challenging, which calls for additional caution in patients undergoing immunotherapy to avoid misdiagnosis and, therefore, begin early appropriate interventions.

Microalgal oil is considered a promising candidate for edible oils. However, investigation of the refining processes of microalgal oil has been limited, especially deacidification. In this work, microcrystalline cellulose (MCC) was pretreated using different methods and utilized for the first time in the deacidification of microalgal oil. Detection results from FTIR and XRD indicated alkali pretreatment had a significant effect on the structure of MCC. Some inter- and intramolecular hydrogen bonds in AMCC (alkali-pretreated MCC) were destroyed, and crystallinity index of cellulose decreased, which increased its adsorption capacity and the reaction of OH groups with free fatty acids. Some NaOH was adsorbed into AMCC through cellulose swelling, which also contributed to deacidification. The interaction with oil was also improved with many cracks and voids on the surface of AMCC. AMCC could reduce the acid value to about 2 mg KOH/g. Comparatively, original MCC and MCC pretreated with microwave or ultrasound did not exhibit the ability to deacidify. Furthermore, the conditions of alkali treatment were optimized. Treatment with 20% NaOH for 20 min was optimal. Compared with other adsorbents, such as sodium silicate and chitosan treated with alkali and resin, only AMCC could effectively reduce acid value while maintaining high lipid recovery. Therefore, AMCC was considered a better adsorbent for the deacidification of microalgal oil.

Three dimensional (3D) extrusion-based printing is a paste-based rapid prototyping process, which is capable of building complex 3D structures. The aim of this study was to explore the feasibility of 3D extrusion-based printing as a pharmaceutical manufacture technique for the fabrication of gastro-floating tablets. Novel low-density lattice internal structure gastro-floating tablets of dipyridamole were developed to prolong the gastric residence time in order to improve drug release rate and consequently, improve bioavailability and therapeutic efficacy. Excipients commonly employed in the pharmaceutical study could be efficiently applied in the room temperature 3D extrusion-based printing process. The tablets were designed with three kinds of infill percentage and prepared by hydroxypropyl methylcellulose (HPMC K4M) and hydroxypropyl methylcellulose (HPMC E15) as hydrophilic matrices and microcrystalline cellulose (MCC PH101) as extrusion molding agent. In vitro evaluation of the 3D printed gastro-floating tablets was performed by determining mechanical properties, content uniformity, and weight variation. Furthermore, re-floating ability, floating duration time, and drug release behavior were also evaluated. Dissolution profiles revealed the relationship between infill percentage and drug release behavior. The results of this study revealed the potential of 3D extrusion-based printing to fabricate gastro-floating tablets with more than 8h floating process with traditional pharmaceutical excipients and lattice internal structure design.

The pursuit of photodegrading environmental pollutants while efficiently utilizing solar energy remains a pivotal endeavor. Herein, Ag2S quantum dots (QDs)/reduced graphene oxide (rGO) composites with Ag2S QDs dispersed on porous stereoscopic rGO-based network were synthesized through a facile hydrothermal process without the addition of any other reducing agent or cross-linker. The as-obtained composites exhibited enhanced adsorption and photocatalysis performance under visible light because of the individual and synergistic effects. The hierarchically stereoscopic structure led to outstanding adsorption ability due to large specific surface area and spongy nature, which facilitated connection between the contaminants and the photocatalytic sites. The incorporation of rGO also suppressed the recombination of electron–hole pairs in the semiconductor and favored the separation from wastewater. Ag2S QDs, whose properties were influenced by quantum size effect, displayed a widened bandgap of 1.82 eV rather than initial 0.92 eV, attributing to stronger redox potential to degrade organic pollutants while efficiently absorbing the visible portion of solar light. With methyl orange as the model pollutant, the comprehensively optimized sample obtained at 150 °C exhibited adsorption capacity of 260 mg g−1 at 25 °C and photodegradation rate 7.8 times that of commercial TiO2 nanoparticles under visible light. Phenol was also analyzed to remove the influence of photosensitization of dyes. Our investigation gives a new insight into the design and fabrication of narrow band semiconductor/rGO composites with enhanced adsorption and photocatalysis.