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Pulmonary surfactant has been attempted as a supportive therapy to treat COVID-19. Although it is mechanistically accepted that the fusion peptide in the S2 subunit of the S protein plays a predominant role in mediating viral fusion with the host cell membrane, it is still unknown how the S2 subunit interacts with the natural surfactant film. Using combined bio-physicochemical assays and atomic force microscopy imaging, it was found that the S2 subunit inhibited the biophysical properties of the surfactant and induced microdomain fusion in the surfactant monolayer. The surfactant inhibition has been attributed to membrane fluidization caused by insertion of the S2 subunit mediated by its fusion peptide. These findings may provide novel insight into the understanding of bio-physicochemical mechanisms responsible for surfactant interactions with SARS-CoV-2 and may have translational implications in the further development of surfactant replacement therapy for COVID-19 patients.

In vitro follicle growth is a promising technology to preserve fertility for cancer patients. We previously developed a three-dimensional (3-D) ovarian tissue culture system supported by mouse tumor cell-derived Matrigel. When murine ovarian tissues at 14 days old were cultured in Matrigel drops, antrum formation and oocyte competence were significantly enhanced compared with those cultured without Matrigel. In this study, we tested whether nonanimal-derived dextran hydrogels can support a 3-D ovarian tissue culture. We employed chemically defined dextran hydrogels consisting of dextran polymers crosslinked with polyethylene glycol (PEG)-based cell-degradable crosslinker. To determine the optimal gel elasticity for the 3-D tissue culture, we measured Young's modulus of dextran hydrogels at four concentrations (1.75, 2.25, 2.75, and 3.25 mmol/L), and cultured ovarian tissues in these gels for 7 days. As a result, 2.25 mmol/L dextran hydrogel with Young's modulus of 224 Pa was appropriate to provide physical support as well as to promote follicle expansion in the 3-D system. To mimic the natural extracellular matrix (ECM) environment, we modified the dextran hydrogels with two bioactive factors: ECM-derived Arg-Gly-Asp (RGD) peptides as a cell-adhesive factor, and activin A. The ovarian tissues were cultured in 2.25 mmol/L dextran hydrogels under four different conditions: Activin-/RGD- (A-R-), A + R-, A-R+, and A + R+. On Day 7 of culture, follicle and oocyte sizes were significantly increased in the RGD-modified conditions compared with those without RGD. The RGD-modified hydrogels also promoted mRNA levels of steroidogenic-related genes and estradiol production in the 3-D ovarian tissue culture. In vitro maturation and developmental competence of follicular oocytes were remarkably improved in the presence of RGD. In particular, blastocyst embryos were obtained only from A-R+ or A+R+ conditions after in vitro fertilization. We also determined synergistic effects of the RGD peptides and activin A on follicle growth and oocyte development in the 3-D tissue culture. In conclusion, our results suggest that RGD-modified dextran hydrogels provide an ECM-mimetic bioactive environment to support folliculogenesis in a 3-D ovarian tissue culture system.

Tear film lipid layer (TFLL) is the outmost layer of the tear film. It plays a crucial role in stabilizing the tear film by reducing surface tension and retarding evaporation of the aqueous layer. Dysfunction of the TFLL leads to dysfunctional tear syndrome, with dry eye disease (DED) being the most prevalent eye disease, affecting 10%–30% of the world population. To date, except for treatments alleviating dry eye symptoms, effective therapeutic interventions in treating DED are still lacking. Therefore, there is an urgent need to understand the biophysical properties of the TFLL with the long-term goal to develop translational solutions in effectively managing DED. Here, we studied the composition-function correlations of an artificial TFLL, under physiologically relevant conditions, using a novel experimental methodology called constrained drop surfactometry. This artificial TFLL was composed of 40% behenyl oleate and 40% cholesteryl oleate, representing the most abundant wax ester and cholesteryl ester in the natural TFLL, respectively, and 15% phosphatidylcholine and 5% palmitic-acid-9-hydroxy-stearic-acid (PAHSA), which represent the two predominant polar lipid classes in the natural TFLL. Our study suggests that the major biophysical function of phospholipids in the TFLL is to reduce the surface tension, whereas the primary function of PAHSA is to optimize the rheological properties of the TFLL. These findings have novel implications in better understanding the physiological and biophysical functions of the TFLL and may offer new translational insight to the treatment of DED.

The spiking neural network (SNN)-based neuromorphic hardware has been extensively studied in dynamic information processing. However, there is still a lack of training algorithms to drive or support the implementation of compact spatio-temporal neuromorphic hardware; and the existing neuromorphic hardware uses excessive on-chip memory to store parameters, which limits its neuron and synapse scale. Here, we introduce a hardware-friendly weight binarized spiking neural network (BSNN) to efficiently recognize the spatio-temporal event-based data. The neuron of the spike response model (SRM) is used in BSNN due to its rich spatio-temporal characteristics. In the training process, a surrogate gradient method is used to replace the derivative of the spike train, and the weights are binarized. Moreover, combined with the spiking characteristics of SNN (i.e., the input/output of SNN and the communications of neurons in SNN are binary spikes), it is possible to replace the hardware-expensive matrix–vector multiplication (MVM) with the hardware-friendly “Signed AND” operation during inference, which is favored for constructing compact neuromorphic hardware. The trained BSNN has competitive recognition accuracies of 99.52% and 62.1%, 97.57%, and 90.35% on the dynamic images dataset N-MNIST and DVS-CIFAR10, dynamic gestures dataset DvsGesture, and dynamic audio dataset N-TIDIGITS18, respectively, which are related to human vision or hearing. The proposed compact SNN training method paves the way for real-time dynamic information processing oriented hardware-saving and power-efficient neuromorphic hardware.

Contaminant-bearing fine biochar particles (FBPs) may exert significantly different toxicity profiles from their contaminant-free counterparts. While the role of FBPs in promoting contaminant uptake has been recognized, it is unclear whether the binding of contaminants can modify the biochemical reactivity and toxicological profiles of FBPs. Here, we show that binding of benzo[a]pyrene (B(a)P, a model polycyclic aromatic hydrocarbon) at environmentally relevant exposure concentrations markedly alters the cytotoxicity of FBPs to macrophages, an important line of innate immune defense against airborne particulate matters (PMs). Specifically, B(a)P-bearing FBPs elicit more severe disruption of the phospholipid membrane, endocytosis, oxidative stress, autophagy, and compromised innate immune defense, as evidenced by blunted proinflammatory effects, compared with B(a)P-free FBPs. Notably, the altered cytotoxicity cannot be attributed to the dissolution of B(a)P from the B(a)P-bearing FBPs, but appears to be related to B(a)P adsorption-induced changes of FBPs bioreactivity toward macrophages. Our findings highlight the significance of environmental chemical transformation in altering the bioreactivity and toxicity of PMs and call for further studies on other types of carbonaceous nanoparticles and additional exposure scenarios.

A novel regime of self-compression is proposed for plasma-based backward Raman amplification(BRA) upon flying focus. By using a pumping focus moving with a speed equal to the group velocity of stimulated Raman backscattering(SRBS), only a short part of SRBS which does always synchronize with the flying focus can be amplified. Due to the asymmetrical amplification, the pulse can be directly compressed in the linear stage of BRA. Therefore, instead of a short pulse, the Raman spontaneous or a long pulse can seed the BRA amplifiers. The regime is supported by the 2D particle-in-cell(PIC) simulation without a seed, presenting that the pump pulse is compressed from 26ps to 116fs, with an output amplitude comparable with the case of a well-synchronized short seed. This method provides a significant way to simplify the Raman amplifiers and overcome the issue of synchronization jitter between the pump and the seed.

Many efforts have been made to improve the neuron integration efficiency on neuromorphic chips, such as using emerging memory devices and shrinking CMOS technology nodes. However, in the fully connected (FC) neuromorphic core, increasing the number of neurons will lead to a square increase in synapsedendrite costs and a high-slope linear increase in soma costs, resulting in an explosive growth of core hardware costs. We propose a co-designed neuromorphic core (SRCcore) based on the quantized spiking neural network (SNN) technology and compact chip design methodology. The cost of the neuron/synapse module in SRCcore weakly depends on the neuron number, which effectively relieves the growth pressure of the core area caused by increasing the neuron number. In the proposed BICS chip based on SRCcore, although the neuron/synapse module implements 1∼16 times of neurons and 1∼66 times of synapses, it only costs an area of 1.79×10

Almost all Langmuir-Blodgett (LB) films were prepared with the classical Langmuir film balance, developed more than a century ago. To date, the success of the classical Langmuir film balance and the LB transfer technique is primarily restricted to the study of self-assembled monolayers at the air-water surface. It is challenging to study self-assembled monolayers at the oil-water interface, since the Langmuir film balance requires stacked oil and water layers. We hypothesize that a newly developed experimental method, called constrained drop surfactometry (CDS), is capable of preparing and characterizing LB films from the oil-water interface.We have developed a novel droplet-based LB transfer technique capable of preparing LB films from the oil-water interface. In conjunction with atomic force microscopy, we have demonstrated the capacity of the CDS in studying a natural pulmonary surfactant film self-assembled at the perfluorocarbon-water interface, and have compared to the LB films prepared from the air-water surface using the classical Langmuir film balance.Our findings have demonstrated a novel paradigm for studying self-assembled monolayers and for preparing LB films from the oil-water interface. The CDS holds great promise for expanding the applicability of the traditional LB transfer technique from the air-water surface to the oil-water interface.

The dramatic impact of COVID-19 on humans worldwide has initiated an extraordinary search for effective treatment approaches. One of these is the administration of exogenous surfactant, which is being tested in ongoing clinical trials.Exogenous surfactant is a life-saving treatment for premature infants with neonatal respiratory distress syndrome. This treatment has also been tested for acute respiratory distress syndrome (ARDS) with limited success possibly due to the complexity of that syndrome. The 60-year history of successes and failures associated with surfactant therapy distinguishes it from many other treatments currently being tested for COVID-19 and provides the opportunity to discuss the factors that may influence the success of this therapy.Clinical data provide a strong rationale for using exogenous surfactant in COVID-19 patients. Success of this therapy may be influenced by the mechanical ventilation strategy, the timing of treatment, the doses delivered, the method of delivery and the preparations utilized. In addition, future development of enhanced preparations may improve this treatment approach. Overall, results from ongoing trials may not only provide data to indicate if this therapy is effective for COVID-19 patients, but also lead to further scientific understanding and improved treatment strategies.

With an increasing prevalence of electronic cigarette (e-cigarette) use, especially among youth, there is an urgent need to better understand the biological risks and pathophysiology of health conditions related to e-cigarettes. A majority of e-cigarette aerosols are in the submicron size and would deposit in the alveolar region of the lung, where they must first interact with the endogenous pulmonary surfactant. To date, little is known whether e-cigarette aerosols have an adverse impact on the pulmonary surfactant. We have systematically studied the effect of individual e-cigarette ingredients on an animal-derived clinical surfactant preparation, bovine lipid extract surfactant, using a combination of biophysical and analytical techniques, including in vitro biophysical simulations using constrained drop surfactometry, molecular imaging with atomic force microscopy, chemical assays using carbon nuclear magnetic resonance and circular dichroism, and in silico molecular dynamics simulations. All data collectively suggest that flavorings used in e-cigarettes, especially menthol, play a predominant role in inhibiting the biophysical function of the surfactant. The mechanism of biophysical inhibition appears to involve menthol interactions with both phospholipids and hydrophobic proteins of the natural surfactant. These results provide novel insights into the understanding of the health impact of e-cigarettes and may contribute to better regulation of e-cigarette products.

Pulmonary enteric adenocarcinoma (PEAC), as a rare histologic subtype of primary lung adenocarcinoma, is defined as an adenocarcinoma in which the enteric component exceeds 50%. It is named after its shared morphological and immunohistochemical features with colorectal cancer. While with such similarity, the differential diagnosis of PEAC and lung metastatic colorectal cancer is a great challenge in the clinic. PEAC may originate from the intestinal metaplasia of respiratory basal cells stimulated by risk factors such as smoking. Current studies have found that肺肠型腺癌是原发性肺腺癌的罕见病理亚型，指肺腺癌中肠型分化成分超过50%者，因其与结直肠腺癌在形态学及免疫组化特征方面有某些共同点而得名，二者间的共同特征也造成肺肠型腺癌与转移性结直肠癌的鉴别诊断具有困难。肺肠型腺癌可能起源于吸烟等危险因素刺激所致的呼吸道基底细胞肠化生，KRAS是其相对高频突变基因，其他驱动基因突变罕见。结合PubMed收录涉及肺肠型腺癌文献分析，肺肠型腺癌CK7阳性率为88.2%(149/169)，CDX2阳性率为78.1%(132/169)，CK20阳性率为48.2%(82/170)，TTF1阳性率为38.8%(66/170)；临床特征方面，肺肠型腺癌平均发病年龄为62岁，男性患者占56.5%(35/62)，吸烟者占78.8%(41/52)，41.4%(24/58)原发病灶位于右肺上叶；治疗方面，现多推荐采用传统非小细胞肺癌治疗方案而非结直肠癌治疗方案对其进行治疗。目前仍亟待更多基础及临床研究，从组学等水平对其分子图谱及发病机制等方面进行深入探索，寻找最优的化疗方案及可能有效的靶向或免疫治疗方案。.

The suspension stability of aluminum-based adjuvant (Alum) plays an important role in determining the Alum-antigen interaction and vaccine efficacy. Inclusion of excipients has been shown to stabilize antigens in vaccine formulations. However, there is no mechanistic study to tune the characteristics of Alum for improved suspension stability. Herein, a library of self-assembled rice-shaped aluminum oxyhydroxide nanoadjuvants i.e., nanorices (NRs), was synthesized through intrinsically controlled crystallization and atomic coupling-mediated aggregations. The NRs exhibited superior suspension stability in both water and a saline buffer. After adsorbing hepatitis B surface antigen (HBsAg) virus-like particles (VLPs), human papillomavirus virus (HPV) VLPs, or bovine serum albumin, NR-antigen complexes exhibited less sedimentation. Further mechanistic study demonstrated that the improved suspension stability was due to intraparticle aggregations that led to the reduction of the surface free energy. By using HBsAg in a murine vaccination model, NRs with higher aspect ratios elicited more potent humoral immune responses. Our study demonstrated that engineered control of particle aggregation provides a novel material design strategy to improve suspension stability for a diversity of biomedical applications.

To elucidate the biological role of miR-4282 in influencing metastasis of epithelial ovarian cancer (EOC) by regulating MIER1.MiR-4282 expressions in 45 cases of EOC specimens and normal controls were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The relationship between miR-4282 and clinical features in EOC patients, including pathological indicators and overall survival, was analyzed. After intervening miR-4282 level in SKOV3 and 3AO cells by plasmid transfection, changes in migratory and invasive abilities were determined by transwell assay and wound healing assay. The target gene of miR-4282 was observed by Dual-Luciferase reporter assay, followed by exploration of its involvement in EOC progression via rescue experiments.MiR-4282 was downregulated in EOC specimens than normal controls. EOC patients expressing low level of miR-4282 had higher incidences of lymphatic metastasis and distant metastasis, as well as worse prognosis than those overexpressing miR-4282. Overexpression of miR-4282 in SKOV3 cells weakened metastatic ability, and conversely, knockdown of miR-4282 in 3AO cells yielded the promotive trends. MIER1 was confirmed to be the target gene binding miR-4282, which was highly expressed in EOC specimens. MIER1 was able to reverse the regulatory effect of miR-4282 on EOC cell metastasis.Lowly expressed miR-4282 in EOC specimens is closely linked to the incidence of metastasis and overall survival. MiR-4282 prevents EOC metastasis by a negative regulation on MIER1.

Both n-butane and iso-butane are important petrochemical raw materials, and their separation is of great significance and full of challenge because of their close boiling characteristic. The ZIF-8 slurry formed with a novel mixed solvent M-water solution as sorption media was adopted to separate the mixture with high efficiency. The iso-/n-butane selectivity of ZIF-8/M-water slurries is as high as 890 with high kinetic performance, even transcending the upper limit of the new materials or membranes. More encouragingly, continuous pilot separation device was established and test results show that the purity and recovery ratio of iso-butane product achieved 99.46 mol% and 87% respectively, which are remarkably superior to the corresponding performance (98.56 mol% and 54%) of the industrial distillation tower. To our best knowledge, this is the first industrial pilot test using MOFs for gas separation, and also an important step forward to the commercial application of MOFs in gas separation.

Ovarian cancer is the most lethal gynecologic malignancy in women with an increasing number of cases worldwide. Chemoresistance is the main obstacle for ovarian cancer treatment during clinical therapy. Previous studies found that programmed cell death 1 ligand 1 (PD-L1) was associated with chemoresistance of cancer. However, there were little reports about the function of PD-L1 involved in chemoresistance of ovarian cancer. In our study, cisplatin (DDP)-resistant SKOV3 and A2780 ovarian cancer cell lines (SKOV3/DDP and A2780/DDP) were established. We found that the expression of PD-L1 was increased and miR-34a-5p was decreased in DDP-resistant cells. PD-L1 silencing inhibited chemoresistance of DDP-resistant ovarian cancer cells to DDP, as evidenced by decreased proliferation, G1-phase cell cycle arrest and increased apoptosis. Western blot assay showed that in the presence of DDP, PD-L1 silencing decreased multidrug resistance protein 1 and Cyclin D1 protein levels, whereas increased cleaved-caspase-3 and cleaved-PARP protein levels in these cells. Moreover, we demonstrated that miR-34a-5p negatively regulated the expression of PD-L1 by targeting its 3'-untranslated region. The effects of miR-34a-5p mimic on DDP-treated SKOV3/DDP cells were reversed by the overexpression of PD-L1. Moreover, the tumorigenicity of DDP-resistant ovarian cancer cells in nude mice treated with DDP was attenuated by miR-34a-5p in vivo. The combined data indicate that miR-34a-5p/PD-L1 axis regulates DDP chemoresistance of ovarian cancer cells, providing a deeper insight into the treatment for ovarian cancer.

Phospholipids are ubiquitous components of biomembranes and common biomaterials used in many bioengineering applications. Understanding adsorption of phospholipids at the air-water surface plays an important role in the study of pulmonary surfactants and cell membranes. To date, however, the biophysical mechanisms of phospholipid adsorption are still unknown. It is challenging to reveal the molecular structure of adsorbed phospholipid films. Using combined experiments with constrained drop surfactometry and molecular dynamics simulations, here, we studied the biophysical mechanisms of dipalmitoylphosphatidylcholine (DPPC) adsorption at the air-water surface. It was found that the DPPC film adsorbed from vesicles showed distinct equilibrium surface tensions from the DPPC monolayer spread via organic solvents. Our simulations revealed that only the outer leaflet of the DPPC vesicle is capable of unzipping and spreading at the air-water surface, whereas the inner leaflet remains intact and forms an inverted micelle to the interfacial monolayer. This inverted micelle increases the local curvature of the monolayer, thus leading to a loosely packed monolayer at the air-water surface and hence a higher equilibrium surface tension. These findings provide novel insights, to our knowledge, into the mechanism of the phospholipid and pulmonary surfactant adsorption and may help understand the structure-function correlation in biomembranes.

A large amount of oily sludge is being produced in the petroleum industry each year and becoming a serious environment issue. An efficient method for separating oil from oily sludge is of great significance for disposing this hazard. In this study, a novel method—water-enhanced CO2 extraction, was proposed to recover oil from the oily sludge. The oily sludge is mixed with water and CO2 thus allowing the oil to be swollen by CO2 under a certain temperature and pressure, leave the solid particles and float upwards to the top interface of the water phase owing to gravitational forces. A series of experiments were conducted to verify the method, optimize the operation conditions and compare it with the traditional approaches like the ultrasonic treatment, the solvent extraction and the supercritical extraction. The results show that up to 80 wt% of the oil in the oily sludge could be recovered using this new method, which is much higher than that using the traditional methods. The most suitable operation temperature, pressure, sludge/water ratio and stirring time were found to be 313–323 K, 3–4 MPa, 1:7 and 90 min, respectively. The proposed water-enhanced CO2 extraction method is efficient in increasing the oil recovery of oily sludge and decreasing its operation conditions compared with traditional oily sludge treatment methods.

Tumoral calcinosis is a rare clinicopathological entity characterized by ectopic soft-tissue calcification, typically periarticular. Normophosphatemic tumoral calcinosis is seldom reported in East Asian populations, and the preoperative diagnosis is often elusive. This study was performed to characterize the clinical profile of normophosphatemic tumoral calcinosis and investigate the presence of the SAMD9 gene mutation. The clinical features, pathological examination findings, and outcomes of 19 subjects were retrospectively reviewed. All patients were analyzed for SAMD9 gene mutation using paraffin-embedded tumoral calcinosis specimens. Nineteen subjects were analyzed (7 males, 12 females). Their mean age at surgery, mean age at symptom onset, and median disease duration was 51.9 ± 17.3 (range 7–75) years, 49.1 ± 17.2 (range 7–74) years, and 1.3 (interquartile range 0.5–3.0) years, respectively. Lesions were located in the hand in 8 (42.1%) subjects; wrist in 5 (26.3%); shoulder in 2 (10.5%); and hip, knee, buttock, and scrotum in 1 (5.3%) subject each. The lesions in 17 (89.5%) subjects were located around the joints [small joints (hand and wrist) in 13 (68.4%) and large joints (shoulder, hip, and knee) in 4 (21.1%)]. Lesions occurred in the upper limbs in 15 (78.9%) subjects and in the lower limbs in 2 (10.5%). Multiple-lesion involvement (distal right index finger and middle finger) occurred in one (5.3%) subject. Symptoms included pain in 15 (78.9%) subjects, impaired mobility in 5 (26.3%), swelling in 5 (26.3%), numbness in 2 (10.5%), and an asymptomatic mass in 2 (10.5%). The serum inorganic phosphorus concentration was normal in all 19 subjects (mean 1.17 ± 0.15 mmol/L). The serum calcium concentration was normal in 18 subjects and low in 1. The serum alkaline phosphatase concentration was normal in all 19 subjects. Pathological examination indicated multiple nodules of calcified materials that manifested an amorphous or granular blue-purple crystal and were surrounded by proliferation of mononuclear or multinuclear macrophages, osteoclastic-like giant cells, fibroblasts, and chronic inflammatory cells. Notably, different phases of pathological manifestations were observed in the same microscopic field. During follow-up (0.5–65.0 months), no recurrence of tumoral calcinosis was observed in 18 (94.7%) subjects, but 1 subject developed in situ recurrence of an asymptomatic subcutaneous mass after 6 months postoperatively. Genetic analysis in all 19 subjects revealed no SAMD9 gene mutations. Most subjects were females and developed calcinosis in adulthood. Small joints (hand and wrist) and the upper limbs were frequently involved. The presence of different phases of pathological features in the same subject suggests that about half of the study participants had been misdiagnosed with another condition (such as gout, osteoarthritis, etc.). Complete surgical excision led to cure without recurrence during follow-up in majority of the study participants.

Surface free energy (SFE) of micro- and nanoparticles plays a crucial role in determining the hydrophobicity and wettability of the particles. To date, however, there are no easy-to-use methods for determining the SFE of particles. Here, with the application of several inexpensive, easy-to-use, and commonly available lab procedures and facilities, including particle dispersion, settling/centrifugation, pipetting, and visible-light spectroscopy, we developed a novel technique called the maximum particle dispersion (MPD) method for quantitatively determining the SFE of micro- and nanoparticles. We demonstrated the versatility and robustness of the MPD method by studying nine representative particles of various chemistries, sizes, dimensions, and morphologies. These are triethoxycaprylylsilane-coated zinc oxide nanoparticles, multiwalled carbon nanotubes, graphene nanoplatelets, molybdenum(IV) sulfide flakes, neodymium(III) oxide nanoparticles, two sizes of zeolites, poly(vinylpolypyrrolidone), and polystyrene microparticles. The SFE of these micro- and nanoparticles was found to cover a range from 21 to 36 mJ/m

Although the process by which the cortical tissues of the brain fold has been the subject of considerable study and debate over the past few decades, a single mechanistic description of the phenomenon has yet to be fully accepted. Rather, two competing explanations of cortical folding have arisen in recent years; known as the axonal tension and the differential tangential expansion models. In the present review, these two models are introduced by analyzing the computational, theoretical, materials-based, and cell studies which have yielded them. Then Four-dimensional bioprinting is presented as a powerful technology which can not only be used to test both models of cortical folding de novo, but can also be used to explore the reciprocal effects that folding associated mechanical stresses may have on neural development. Therein, the fabrication of “smart” tissue models which can accurately simulate the in vivo folding process and recapitulate physiologically relevant stresses are introduced. We also provide a general description of both cortical neurobiology as well as the cellular basis of cortical folding. Our discussion also entails an overview of both 3D and 4D bioprinting technologies, as well as a brief commentary on recent advancements in printed central nervous system tissue engineering.

Satellite altimetry has been used to observe the Arctic sea ice in long term and large scale, and the records show a continued decline for Arctic sea ice thickness over decades. In this study, the sea ice freeboard in Beaufort Sea of Arctic have been estimated using CryoSat-2 data, and validated with Upward Looking Sonar (ULS) data of Beaufort Gyre Exploration Project (BGEP). The results show an obvious seasonal variation of the Beaufort Sea with a high reliability estimation of the sea ice freeboard. The average height of the sea ice freeboard increase from January to March and achieve the maximum value 0.38 m in March. The sea ice melts after March and the average height of the sea ice freeboard reduces to the minimum 0.12 m in August. In the next few months the sea water begins to freeze and the average height of the sea ice freeboard will increase to the maximum value.

The high efficiency separation of ethane from natural gas becomes significant due to the occurrence of revolution in shale gas. Herein a new approach of continuous sorption separation was developed...

Introduction E-cigarette (EC) and vaping use continue to remain popular amongst teenage and young adult populations, despite several reports of vaping associated lung injury. One of the first compounds that EC aerosols comes into contact within the lungs during a deep inhalation is pulmonary surfactant. Impairment of surfactant’s critical surface tension reducing activity can contribute to lung dysfunction. Currently, information on how EC aerosols impacts pulmonary surfactant remains limited. We hypothesized that exposure to EC aerosol impairs the surface tension reducing ability of surfactant. Methods Bovine Lipid Extract Surfactant (BLES) was used as a model surfactant in a direct exposure syringe system. BLES (2ml) was placed in a syringe (30ml) attached to an EC. The generated aerosol was drawn into the syringe and then expelled, repeated 30 times. Biophysical analysis after exposure was completed using a constrained drop surfactometer (CDS). Results Minimum surface tensions increased significantly after exposure to the EC aerosol across 20 compression/expansion cycles. Mixing of non-aerosolized e-liquid did not result in significant changes. Variation in device used, addition of nicotine, or temperature of the aerosol had no additional effect. Two e-liquid flavours, menthol and red wedding, had further detrimental effects, resulting in significantly higher surface tension than the vehicle exposed BLES. Menthol exposed BLES has the highest minimum surface tensions across all 20 compression/expansion cycles. Alteration of surfactant properties through interaction with the produced aerosol was observed with a basic e-liquid vehicle, however additional compounds produced by added flavourings appeared to be able to increase inhibition. Conclusion EC aerosols alter surfactant function through increases in minimum surface tension. This impairment may contribute to lung dysfunction and susceptibility to further injury.

n-butane and isobutane are important petrochemical raw materials. Their separation is challenging because of their similar properties, including boiling point. Here, we report a zeolitic imidazolate framework-8 (ZIF-8)/N,N-Dimethylpropyleneurea (DMPU)-water slurry as sorption material to separate butane mixtures. The isobutane/n-butane selectivity of ZIF-8/DMPU-water slurries is as high as 890 with high kinetic performance, which transcends the upper limit of various separation materials or membranes reported in the literature. More encouragingly, a continuous pilot separation device was established, and the test results show that the purity and recovery ratio of isobutane product are 99.46 mol% and 87%, respectively, which are superior to the corresponding performance (98.56 mol% and 54%) of the industrial distillation tower. To the best of our knowledge, the use of metal-organic frameworks (MOFs) for gas separation in pilot scale remains underexplored, and thus this work provides a step forward to the commercial application of MOFs in gas separation.

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a newly discovered class of endogenous lipids that consist of two acyl chains connected through a single ester bond. Being a unique species of FAHFAs, (O-acyl)-ω-hydroxy fatty acids (OAHFAs) differ from other FAHFAs in that their hydroxy fatty acid backbones are ultralong and their hydroxy esterification is believed to be solely at the terminal (ω-) position. Only in recent years with technological advances in lipidomics have OAHFAs been identified as an important component of the tear film lipid layer (TFLL). It was found that OAHFAs account for approximately 4 mol% of the total lipids and 20 mol% of the polar lipids in the TFLL. However, their biophysical function and contribution to the TFLL is still poorly understood. Here we studied the molecular biophysical mechanisms of OAHFAs using palmitic-acid-9-hydroxy-stearic-acid (PAHSA) as a model. PAHSA and OAHFAs share key structural similarities that could result in comparable biophysical properties and molecular mechanisms. With combined biophysical experiments, atomic force microscopy observations, and all-atom molecular dynamics simulations, we found that the biophysical properties of a dynamic PAHSA monolayer under physiologically relevant conditions depend on a balance between kinetics and thermal relaxation. PAHSA molecules at the air-water surface demonstrate unique polymorphic behaviors, which can be explained by configurational transitions of the molecules under various lateral pressures. These findings could have novel implications in understanding biophysical functions that FAHFAs, in general, or OAHFAs, specifically, play in the TFLL.