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Highlights • TBAB/TBPB semiclathrate hydrates were formed at 2.57 mol% with CO 2 + CH 4. • Different shaped hydrate crystals were formed in TBPB and TBAB solutions. • TBPB hydrate grew laterally at the gas/liquid interface and quickly covered the gas/liquid interface. • TBAB hydrate formed around the gas/liquid interface and dropped downward. • A higher gas uptake and CO 2 separation efficiency obtained in TBAB solutions. Abstract This work presents a morphological and kinetic investigation of tetra- n -butyl ammonium bromide (TBAB) or tetra- n -butyl phosphonium bromide (TBPB) semiclathrate hydrates formed with a CO 2 + CH 4 gas mixture at the stoichiometric concentration (2.57 mol%). A 3-stage procedure was proposed and employed in the experiments. All experiments were performed at 2.8 MPa and a subcooling of 12 K was used as driving force for hydrate nucleation and growth. It was found that the shapes of hydrate crystals formed in TBPB and TBAB solutions were quite different. Besides, the TBPB semiclathrate hydrate grew laterally at gas/liquid interface and quickly covered the interface while the TBAB semiclathrate hydrate initially formed around the gas/liquid interface and then sank to the reactor bottom. As a consequence, gas uptake and the rate of hydrate growth obtained in TBAB solutions were higher than that in TBPB solutions. It was also found that CO 2 content in hydrate phase, CO 2 recovery, and separation factor obtained in TBAB solutions were higher than those obtained in TBPB solutions. Therefore, TBAB semiclathrate hydrate formed at the stoichiometric concentration and quiescent conditions will be a promising approach to improve the hydrate based CO 2 separation from the CO 2 + CH 4 gas mixture. [ABSTRACT FROM AUTHOR]

Abstract In the present work, we report an investigation of using an anionic surfactant sulfonated lignin (SL) to promote gas hydrate formation for CO 2 capture from a CO 2 /CH 4 gas mixture. The experiments were performed at 277.15 K in a stirred tank reactor. The initial overpressure (driving force) for hydrate formation was fixed at Δ P = 2.5 MPa. The impacts of the SL presence on hydrate growth behavior and CO 2 separation efficiency were elucidated. The results indicated that hydrate nucleation was prolonged in the presence of SL but this stage was accelerated when adding 1.0 mol% tetrahydrofuran (THF) into the SL solution. Compared to THF/SL and sodium dodecyl sulfate (SDS) solutions, CO 2 recovery obtained in SL solutions was increased to 63.5 ± 2.9% and the separation factor was 4.0 ± 0.8. Gas consumption obtained in SL solutions was higher than that obtained in other systems like liquid water, SDS solution, THF solution, and tetra- n -butyl phosphonium bromide (TBPB) solution. Therefore, sulfonated lignin can be used as a promising surfactant to improve hydrate formation kinetics as well as the efficiency of CO 2 capture from CO 2 /CH 4 gas mixture, but there still exists a space to increase the CO 2 selectivity in the presence of SL. Highlights • A surfactant sulfonated lignin was used to promote hydrate based CO 2 capture from CO 2 /CH 4. • Gas uptake for hydrate formation was increased in sulfonated lignin solutions. • CO 2 separation efficiency was greatly improved in sulfonated lignin solutions. [ABSTRACT FROM AUTHOR]

Summary: Aims: Autophagy has been regarded as a promising therapeutic target for spinal cord injury (SCI). Erythropoietin (EPO) has been demonstrated to exhibit neuroprotective effects in the central nervous system (CNS); however, the molecular mechanisms of its protection against SCI remain unknown. This study aims to investigate whether the neuroprotective effects of EPO on SCI are mediated by autophagy via AMP‐activated protein kinase (AMPK) signaling pathways. Methods: Functional assessment and Nissl staining were used to investigate the effects of EPO on SCI. Expressions of proteins were detected by Western blot and immunohistochemistry. Results: Treatment with EPO significantly reduced the loss of motor neurons and improved the functional recovery following SCI. Erythropoietin significantly enhanced the SCI‐induced autophagy through activating AMPK and inactivating mTOR signaling. The inhibitor of AMPK, compound C, could block the EPO‐induced autophagy and beneficial action on SCI, whereas the activator of AMPK, metformin, could mimic the effects of EPO. In the in vitro studies, EPO enhanced the hypoxia‐induced autophagy in an AMPK‐dependent manner. Conclusions: The AMPK‐dependent induction of autophagy contributes to the neuroprotection of EPO on SCI. [ABSTRACT FROM AUTHOR]

Graphical abstract Dissociation thermogram of TBAC semiclathrate hydrate formed at 3.3 mol% TBAC in the presence of low-concentration coal mine gas. Highlights • TBAC semiclathrate hydrate was used for CH 4 recovery from a coal mine gas. • Phase equilibrium data at different TBAC concentrations were measured. • Phase behaviors of TBAC-coal mine gas mixed semiclathrate hydrate were tested by HP µ-DSC. • An optimum condition for semiclathrate-based CH 4 separation was determined. Abstract This work presents an investigation of using tetra- n -butyl ammonium chloride (TBAC) semiclathrate hydrate to separate CH 4 from a low-concentration coal mine gas containing 30 mol% CH 4 , 60 mol% N 2 , and 10 mol% O 2. Phase equilibrium data of TBAC semiclathrate hydrate formed in the presence of low-concentration coal mine gas with TBAC concentration ranging from 0.49 mol% to 3.3 mol% were measured and reported. A high pressure micro-differential scanning calorimeter (HP µ-DSC) was employed to characterize the phase behaviors of TBAC semiclathrate hydrate formed in the presence of coal mine gas with TBAC concentration fixed at 3.3 mol% (the stoichiometric concentration of TBAC semiclathrate). It was found that pure TBAC semiclathrate hydrate coexists with the TBAC-coal mine gas mixed hydrate in the pressure range of (1.4–6.2 MPa). In addition, kinetic experiments were performed to elucidate the effects of TBAC concentration, subcooling, and sodium dodecyl sulfate (SDS) concentration on CH 4 separation efficiency and an optimum experimental condition for semiclathrate-based CH 4 recovery was screened. The highest CH 4 recovery and separation factor were obtained at the conditions of 0.49 mol% TBAC, △ T = 8 K, and 900 ppm SDS. It was found that CH 4 recovery obtained at 0.49 mol% TBAC is comparable with that obtained at 0.29 mol% TBAB, whereas CH 4 concentration of the gas mixture released from the TBAC hydrate (49.6 mol%) is increased substantially comparing to that obtained at 0.29 mol% TBAB (42.5 mol%). [ABSTRACT FROM AUTHOR]

A synthetic strategy based on biogenetic building blocks for the collective and divergent biomimetic synthesis of cleistoperlones A−F, a cinnamoylphloroglucinol collection discovered from Cleistocalyx operculatus, has been developed. These syntheses proceeded successfully in only six to seven steps starting from commercially available 1,3,5‐benzenetriol and involving oxidative activation of stable biogenetic building blocks as a crucial step. Key features of the syntheses include a unique Michael addition/ketalization/1,6‐addition/enol‐keto tautomerism cascade reaction for the construction of the dihydropyrano[3,2‐d]xanthene tetracyclic core of cleistoperlones A and B, and a rare inverse‐electron‐demand hetero‐Diels–Alder cycloaddition for the establishment of benzopyran ring in cleistoperlones D−F. Moreover, cleistoperlone A exhibited significant antiviral activity against acyclovir‐resistant strains of herpes simplex virus type 1 (HSV‐1/Blue and HSV‐1/153). [ABSTRACT FROM AUTHOR]

A synthetic strategy based on biogenetic building blocks for the collective and divergent biomimetic synthesis of cleistoperlones A−F, a cinnamoylphloroglucinol collection discovered from Cleistocalyx operculatus, has been developed. These syntheses proceeded successfully in only six to seven steps starting from commercially available 1,3,5‐benzenetriol and involving oxidative activation of stable biogenetic building blocks as a crucial step. Key features of the syntheses include a unique Michael addition/ketalization/1,6‐addition/enol‐keto tautomerism cascade reaction for the construction of the dihydropyrano[3,2‐d]xanthene tetracyclic core of cleistoperlones A and B, and a rare inverse‐electron‐demand hetero‐Diels–Alder cycloaddition for the establishment of benzopyran ring in cleistoperlones D−F. Moreover, cleistoperlone A exhibited significant antiviral activity against acyclovir‐resistant strains of herpes simplex virus type 1 (HSV‐1/Blue and HSV‐1/153). [ABSTRACT FROM AUTHOR]

In this work, a high pressure micro-differential scanning calorimeter (HP µ-DSC) was employed to measure the phase equilibrium data and dissociation enthalpies of tetra- n -butylammonium chloride (TBAC) semiclathrate hydrate formed in the presence of CO 2 , CH 4 , and CO 2 + CH 4 . The TBAC concentration varied from 1.0 mol% to 5.0 mol%, and the operating pressure changed from 1.0 MPa to 5.0 MPa. It was found that the phase boundary of TBAC semiclathrate hydrate formed at 3.3 mol% TBAC was lower than that obtained at 1.0 mol% and 5.0 mol% TBAC in the presence of CO 2 + CH 4 , and the hydrate dissociation enthalpy obtained at 3.3 mol% TBAC was larger than that obtained at 1.0 mol% and 5.0 mol% TBAC. This result indicates that TBAC semiclathrate (TBAC·29.7H 2 O) formed at the stoichiometric concentration (3.3 mol%) was more stable than that formed at 1.0 mol% and 5.0 mol% TBAC in the presence of CO 2 + CH 4 . In addition, pure TBAC semiclathrate hydrate and the mixed TBAC + CO 2 + CH 4 semiclathrate hydrate were found to coexist at 1.0 mol% TBAC. The hydrate dissociation enthalpy for the mixed TBAC + CO 2 + CH 4 semiclathrate hydrate formed at 3.3 mol% TBAC was found to increase with the increase of pressure. This is probably because a larger amount of the CO 2 + CH 4 gas mixture was incorporated into the TBAC semiclathrate hydrate at a higher pressure. [ABSTRACT FROM AUTHOR]

This work presents an investigation of using tetra- n -butyl phosphonium bromide (TBPB) semiclathrate hydrate for CO 2 capture from simulated shale gas that is composed of 40% CO 2 and 60% CH 4 in mole fraction. The experiments were performed in a stirred tank reactor with the mass fraction of TBPB ( w TBPB ) varying from 5.0% to 33.2%. The phase equilibrium data of TBPB semiclathrate hydrate formed in the presence of the 40% CO 2 /CH 4 gas mixture were measured and reported. The effects of TBPB concentration on gas solubility, hydrate formation kinetics, and CO 2 separation efficiency were investigated in the temperature range of 278.1–284.2 K with the initial pressure fixed at 2.8 MPa. The results indicated that at a fixed driving force (overpressure), the gas uptake obtained at the induction time was nearly constant, despite the variation in TBPB concentration, while the rate of hydrate formation increased with the increase in TBPB concentration. Compared to the results obtained at a mole fraction of 1% THF, it was found that enhanced hydrate formation kinetics, a higher CO 2 separation factor (31.7 ± 3.3), and a higher operating temperature (284.2 K) were obtained at the stoichiometric TBPB concentration ( w TBPB = 33.2%). Therefore, TBPB may be used as a promising promoter for hydrate-based CO 2 capture from the simulated shale gas (CO 2 /CH 4 gas mixture). [ABSTRACT FROM AUTHOR]

In this work, we utilize four parallel reservoirs to model the chaotic dynamics of the output four polarization components (PCs) from a driving QD spin-VCSEL. Here, the four parallel reservoirs are implemented using the four PCs of a reservoir QD spin-VCSEL. High-quality chaos synchronizations of four pairs of PCs can be realized by using the four parallel reservoirs based on a reservoir QD spin-VCSEL. Under these high-quality synchronizations, we successfully implement four-channel secure communications with 4 × 100 Gb/s 16 QAM messages under guaranteeing. We further discuss the performances of the bit error ratios (B E R s) for four decoding messages under different parameters. We show that all B E R s via different parameters are less than 7 × 10−3, denoting that high-quality data-transmissions can be potentially obtained in the system. Moreover, we prove that our proposed multi-channel optical chaotic communication scheme has the same level of security as the traditional schemes. Our findings show that the delay-based optical reservoir computing based on a QD spin-VCSEL provides an effective method for realization of multi-channel optical secure communication. • We propose to use four parallel optical reservoirs to precisely predict the chaotic dynamics of the four polarization components output by a driving QD spin-VCSEL, respectively. • We successfully implement four-channel secure communications with 4×100 Gb/s 16 QAM messages. • All bit error ratios via different parameters are less than 0.007, denoting that high-quality data-transmissions can be obtained. • Our proposed multi-channel optical chaotic communication scheme has the same level of security as the traditional schemes. • Our findings show that the delay-based optical reservoir computing based on a QD spin-VCSEL provides an effective method for realization of multi-channel optical secure communication. [ABSTRACT FROM AUTHOR]

A supply- and demand-driven supply chain model was built by introducing supply and demand function and price adjustment equation simultaneously, then the lead time demand was predicted and the bullwhip effect was analyzed. The results show supply and demand fluctuations can’t eliminate the bullwhip effect in any case due to the systematic factor, while there is an inverse relationship between the impacts of supply and demand fluctuation imposed on the bullwhip effect. The supplier has been in an active position in reducing the bullwhip effect, and reducing lead time is apparent to alleviate the bullwhip effect if lead time is in the optimal interval. Meanwhile, the supplier can develop production plan depending on previous multi-period historical product price information to restrain the bullwhip effect, and the retailer should choose the right sales strategy to control the bullwhip effect after analyzing consumers’ price consumption psychology and understanding consumers’ price sensitivity. [ABSTRACT FROM AUTHOR]

In this work, we predicted the hydrate formation conditions for the pure and mixed gas systems of CH 4 , N 2 , O 2 and CO 2 in the presence of cyclopentane or cyclohexane. Chen-Guo model coupled with the predictive Soave-Redlich-Kwong (PSRK) group contribution method was used to calculate the three-phase equilibrium, and the UNIFAC model was employed to calculate the activity coefficient of the liquid phase. The pressure-corrected Henry’s law was employed to calculate the mole fraction of gas components existing in the aqueous phase except water. The prediction results and the percent of Absolute Average Deviation for the calculated hydrate formation pressures and temperatures were presented. It was found that the results predicted in this work agree well with those reported in the literature. Cyclopentane and cyclohexane in aqueous phase was assumed to evaporate into the gas phase and may change the gas components and the corresponding mole fractions in the gas phase. However, the results showed that the concentration variation of cyclopentane or cyclohexane has slight impact on the hydrate formation thermodynamics. [ABSTRACT FROM AUTHOR]

• Standing wave resonant states in the bulk dielectric can greatly enhance the nonlinearity of graphene arrays. • Multiple optical bistabilities and multistability have been achieved with a red-detuning in incident wavelengths. • The multiple bistabilities and their characteristics can be modulated by the bulk thickness and the graphene chemical potential. We theoretically investigate the optical bistability in compound systems composed of one-dimensional graphene arrays and dielectrics. Graphene sheets are periodically assembled in the dielectric substrate to form the arrays of graphene and a bulk dielectric contacts on the right of the structure. The standing wave resonances can enhance the nonlinearity of graphene arrays and consequently multiple optical bistabilities are achieved with appropriate red-detunings in incident wavelengths. The realization of multiple bistabilities and the bistable thresholds depend on the thickness of the bulk dielectric. Otherwise, the multiple bistabilities could be modulated by impurity-doping in graphene or an external gate voltage on graphene arrays as well. This investigation has potentials applied in multivalued all-optical switches and optical memory. [ABSTRACT FROM AUTHOR]

In this study, a fixed bed of pulverized coal particles was employed to enhance the precombustion CO 2 capture from fuel gas (40 mol% CO 2 /H 2 ). The performance of the HAHF (hybrid adsorption-hydrate formation) process occurred in the fixed bed was evaluated at different liquid saturations and operation pressures. The experiments were carried out at 274.2 K with the pressure varying from 3.0 MPa to 6.0 MPa. 1.0 mol% THF (tetrahydrofuran) solution instead of liquid water was used to saturate the fixed bed and reduce the hydrate phase equilibrium conditions. The results indicated that gas hydrate nucleation in the fixed bed was quickly induced by gas adsorption in coal particles. The HAHF process was dominated by hydrate formation as the fixed bed saturation increased, and the CO 2 recovery and separation factor were increased. Gas consumption during the HAHF process was promoted with the increase of operation pressure, but the CO 2 recovery and separation factor decreased. In the fixed bed of coal particles saturated by 1.0 mol% THF solution the highest gas uptake obtained was 51.9 mmol of gas/mol of water, which was comparable with that obtained in the fixed bed of silica sand in the presence of 5.53 mol% THF. Therefore, compared with the hydrate based gas separation process, the hybrid adsorption-hydrate formation process proposed in this study could be a viable option for CO 2 capture from fuel gas. [ABSTRACT FROM AUTHOR]

In this work, a water-in-oil (W/O) emulsion was developed using liquid water, mineral oil, Sorbitan monooleate (Span 80), and cyclopentane. It was employed to enhance gas hydrate formation for CH 4 separation from a simulated coal mine methane (CMM) gas (30 mol% CH 4 , 60 mol% N 2 , and 10 mol% O 2 ). The stability test at atmospheric pressure and at a high pressure of 3.5 MPa showed that stable W/O emulsions were obtained when the water–oil volume ratio (WOR) was below 80%. The emulsified droplets size was measured with WOR ranging from 10% to 70%. Then kinetic experiments of CH 4 separation by hydrate formation in W/O emulsions were carried out at 273.6 K and (3.5–5.0) MPa in batch operation. The results indicated that water–oil volume ratio is a key factor that affects the kinetics of gas hydrate formation from the CMM gas mixture. Hydrate nucleation was observed to occur faster while WOR was decreased, and gas uptake increased significantly with the decrease of WOR. CH 4 concentration in the recovered gas mixture was increased to 52 mol% as compared to 30 mol% in the original gas mixture through one-stage hydrate formation in the W/O emulsions. It was found that the experimental conditions of 273.6 K, 3.5 MPa and WOR = 30% were favorable for CH 4 recovery from the CMM gas. The CH 4 recovery obtained under these conditions was 43%. It was higher than those obtained at WOR = 10% and 70%, and was greatly increased as compared with those obtained in the same reactor with the presence of TBAB (26%) and CP (33%). [ABSTRACT FROM AUTHOR]

In this work, the performance of hydrate formation for CO 2 removal from a simulated recovered shale gas (40 mol% CO 2 and 60 mol% CH 4 ) was evaluated in liquid water, and THF and THF/SDS solutions. Experiments were carried out at a fixed temperature of 277.15 K and in the pressure range of (2.8–6.7) MPa. The impact of driving force (overpressure) on hydrate growth and CO 2 selectivity was studied both in liquid water and in THF solutions. It was found that higher driving force resulted in a reduction of the final gas uptake as well as a significant decrease of the CO 2 recovery and separation factor. The results indicated that mass transfer for hydrate growth was greatly hindered at high driving force, and the competition between CH 4 and CO 2 molecules for the occupancy of hydrate cavities became stronger with the increase of driving force. Although the kinetics of hydrate formation with the CO 2 /CH 4 gas mixture was improved by adding THF and SDS into liquid water, the selectivity for CO 2 removal from the CO 2 /CH 4 gas mixture was compromised as compared to that in liquid water. The highest CO 2 recovery (52%) and separation factor (8.8) were obtained at a low driving force (2.5 MPa) in liquid water, which were much higher than those obtained in THF and THF/SDS solutions. As a result, enhancing the kinetics of hydrate formation without reducing CO 2 selectivity is the key factor to improve the hydrate based gas separation process for CO 2 removal from the CO 2 /CH 4 gas mixture. [ABSTRACT FROM AUTHOR]

The discovery of small molecular inhibitors targeting essential and conserved bacterial drug targets such as FtsZ protein is a promising approach to fight against multi-drug resistant bacteria. In the present study, two new series of FtsZ inhibitors based on a 1-methylquinolinium scaffold were synthesized. The inhibitors possess a variety of substituent groups including the cyclic or linear amine skeleton at the 2- and 4-position of the quinolinium ring for structure-activity relationship study. In general, the inhibitors bearing a cyclic amine substituent at the 4-position of the quinolinium ring showed better antibacterial activity (MIC down to 0.25 μg/mL) than that at the 2-position, especially against Gram-positive bacteria. Among the twenty FtsZ inhibitors examined in various assays, A3 was identified to exhibit excellent antibacterial activity against S. aureus (MIC = 0.5–1 μg/mL), S. epidermidis (MIC = 0.25 μg/mL) and E. faecium (MIC = 1–8 μg/mL). More importantly, A3 showed low hemolytic toxicity (IC 5 = 64 μg/mL) and was found not readily to induce drug resistance. A3 at 2–8 μg/mL promoted the polymerization of FtsZ and interrupted the bacterial division. Furthermore, the ligand-FtsZ interaction study conducted with circular dichroism and molecular docking revealed that A3 induced secondary structure changes of FtsZ protein upon binding to the interdomain cleft of the protein. A3 is thus a potent inhibitor of FtsZ and shows potential to be used as a new antibacterial agent against drug-resistant bacteria. [Display omitted] • Rational design of novel quinolinium-based derivatives targeting FtsZ protein. • A potent quinolinium-based inhibitor of FtsZ was identified. • The modification on quinolinium ring enhances antibacterial activity. • A3 showed low hemolytic toxicity and low tendency to induce drug resistance. [ABSTRACT FROM AUTHOR]

Coal mine methane (CMM) gas is a sort of unconventional natural gas that can be used as a clean supplementary energy resource when methane is purified. In this work, methane separation from a low-concentration CMM gas (30 mol% CH 4 , 60 mol% N 2 , and 10 mol% O 2 ) was investigated using gas hydrate formation in a stirred reactor and in a fixed bed of silica sand with the presence of tetrahydrofuran (THF) and sodium dodecyl sulfate (SDS). The concentration of THF and SDS was fixed at 1.0 mol% and 500 ppm, respectively. The experiments were carried out in batch operation with the initial pressure fixed at 3.6 MPa, and the temperature was set at 277.15 K. The results indicated that gas hydrate formation in the stirred reactor and in the fixed bed of silica sand were both promoted by adding SDS in THF solutions. It was found that the hydrate-based separation process for CH 4 recovery from the CMM gas mixture performed better in the stirred reactor as compared to the fixed bed of silica sand employed in this work. The CH 4 recovery obtained at 1.0 mol% THF and 500 ppm SDS in the stirred reactor was about 40.5%, which was much higher than those obtained in TBAB solutions (26.2%) and cyclopentane/SDS solutions (33.3%). [ABSTRACT FROM AUTHOR]

Fat hypertrophy, intravascular coagulation, and fat emboli are important risk factors of steroid-induced ischemic bone necrosis (SI-IBN) which may develop during the initial one year after commencing the use of steroids. This pathology is best studied by MRI, particularly for its staging. The cautious strategies such as low dose, oral route, short duration of steroid usage, use of steroid sparing agent, and alcohol avoidance should be followed as a traditional therapy. The objective of this review article was to recognize and evaluate various Treatment strategies for steroid-induced ischemic bone necrosis of femoral head. Literature Search: Various electronic databases including PubMed, Google and Cochrane library were comprehensively searched for articles on steroid-induced ischemic bone necrosis of femoral head and its treatment strategies. Ninety four articles were reviewed, examined and importantly appraised and the most appropriate 32 papers were used to write this review article. Conclusion: Bisphosphonates, alendronate, and hyperbaric oxygen (HBO) treatments have been reported to be effective against IBN. To recommend the regular use of bisphosphonate in IBN patients, more evidences with a larger number of patients are required to verify its therapeutic effectiveness. Core decompression, osteotomy, bone graft and tantalum rod are the surgical approaches for the management of IBN. Advance form of IBN (bone tissue collapse) is advised to be treated with arthroplasty which should be durable, particularly in young patients. [ABSTRACT FROM AUTHOR]

The acoustic signals of the laser micro plasma expansion for the femtosecond laser ablating pure Al, Cu and Fe target materials have been detected by the fiber Fabry–Perot ( F – P ) acoustic emission sensing probe. The frequency and amplitude of the acoustic emission spectrum have been analyzed. The results show that the detected acoustic emission frequency spectrum pattern is fixed and different for the three kinds of target materials. The amplitude of the acoustic emission spectrum grows up along with the enhancement of laser ablation energy. The amplitude of the acoustic emission spectrum decreases when the detection distance is enlarged. The developed measuring system provides a potential method aiming at the detection of solid materials based on the acoustic signals excided by femtosecond laser ablating target materials using the fiber F – P acoustic emission sensing probe. [ABSTRACT FROM AUTHOR]

In this work, the phase equilibriumconditions for gas hydratesformed from a CO2/CH4gas mixture (0.4 CO2and 0.6 CH4in mole fraction) in the presencetetrahydrofuran (THF) were measured using the isothermal pressuresearch method and reported. The THF mole fractions used were 0.005,0.01, 0.03, and 0.05 respectively. It was found that the equilibriumhydrate formation conditions obtained in the presence of THF shiftedto high temperatures and low pressures as compared with those obtainedusing the same gas mixture in pure water. For the hydrates formedat a given temperature, the phase equilibrium pressure was observedto decrease as the THF mole fraction increased from 0.005 to 0.05.Therefore, it was confirmed that THF can be used as an effective thermodynamicpromoter for CO2separation from the CO2/CH4gas mixture by hydrate formation. The heat of hydrate dissociationwas also determined based on the measured phase equilibrium data ofthe gas hydrates formed from the CO2/CH4gasmixture in the presence of THF. It was found that structure II hydratewas formed from the CO2/CH4gas mixture in thepresence of THF. Then the impact of driving force on CO2separation from the CO2/CH4gas mixture wasinvestigated. The results indicated that the competition between CO2and CH4molecules for hydrate cage occupancy becamestronger with the increase of driving force. Thus, a lower pressureat the given temperature is preferred for CO2separationfrom the CO2/CH4gas mixture by hydrate formationin the presence of THF. [ABSTRACT FROM AUTHOR]

We have developed a polydimethylsiloxane (PDMS) pattern with arrays of microwells for the formation of multicellular aggregates by C17.2 neural stem cells. Upon interfacing with the patterns, the neural stem cells would firstly attach to the microwell sidewalls, forming cellular strips on day 1 after plating. For channel connected microwells, cellular strips on the concave semi-cylindrical sidewall surfaces continued among wells and through channels, followed by strip peeling due to prestress arising from actin filaments and assembly of suspending cellular aggregates within the microwells in the following 1–2 days. Our results also suggested that a small microwell diameter of 80 and 100 μm and a narrow channel width of 20 μm would facilitate the aggregate formation among the structural dimensions tested. Finite element method (FEM) simulation revealed that cellular strips on the semi-cylindrical sidewall surfaces peeled under significantly smaller prestresses (critical peeling prestress, CPP), than cells on flat substrates. However, the CPP by itself failed to fully account for the difference in aggregate inducing capability among the patterns addressed, suggesting cell growth behaviors might play a role. This study thus justified the current patterning method as a unique and practical approach for establishing 3D neural stem cell-based assay platforms. [ABSTRACT FROM AUTHOR]

The number and function of endothelial progenitor cells (EPCs) may be a predictive factor for the severity and outcome of cardiovascular disease. However, the manipulation of bone marrow mononuclear cell (BMMC) cultures for EPCs is an elaborate and difficult procedure in small experimental animals. The present study aimed to assess the feasibility of whole bone marrow cell (WBMC) culture for expanding EPCs in small experimental animals. C57BL/6 mice (age, 3-4 weeks; weight, 9.47±0.76 g) were used as the experimental animals, and WBMCs were isolated from the femora and tibiae and cultured in endothelial cell growth medium-2. A BMMC culture for EPCs was used as a control. EPC growth, phenotype and functions were assessed in vitro and in vivo. The results demonstrated that EPCs were easily obtained from a WBMC culture in vitro. The cells exhibited similar growth and biological characteristics when compared with the EPCs derived from the traditional BMMC culture system. Thus, the cells were able to simultaneously bind to lectin and cause phagocytosis of acetylated-low density lipoproteins. In addition, the cells exhibited high expression levels of cluster of differentiation 34 and fetal liver kinase 1, and possessed similar functional properties to BMMC-derived EPCs, including vascular network formation, proliferation, adhesion and migration abilities in vitro. Thus, WBMC-derived EPCs can improve the outcome of pulmonary vascular disease when transplanted into a monocrotaline-induced pulmonary hypertension mouse model. The results of the present study indicated that the WBMC culture system is a more convenient and effective method of obtaining and expanding EPCs compared with BMMC culture, with the advantage of a simplified procedure. [ABSTRACT FROM AUTHOR]

The modern CPU's design, including the deep memory hierarchies and SIMD/vectorization capability have a more significant impact on algorithms' efficiency than the modest frequency increase observed recently. The current introduction of wide vector instruction set extensions (AVX and SVE) motivated vectorization to become a critical software component to increase efficiency and close the gap to peak performance. In this paper, we investigate the impact of the vectorization of MPI reduction operations. We propose an implementation of predefined MPI reduction operations using vector intrinsics (AVX and SVE) to improve the time-to-solution of the predefined MPI reduction operations. The evaluation of the resulting software stack under different scenarios demonstrates that the approach is not only efficient but also generalizable to many vector architectures. Experiments conducted on varied architectures (Intel Xeon Gold, AMD Zen 2, and Arm A64FX), show that the proposed vector extension optimized reduction operations significantly reduce completion time for collective communication reductions. With these optimizations, we achieve higher memory bandwidth and an increased efficiency for local computations, which directly benefit the overall cost of collective reductions and applications based on them. • Design and investigation of vector-based reduction operation for MPI reduction. • Implementation using Intel AVXs and Arm SVE to demonstrate the efficiency of our vectorized reduction operation. • Experiments with MPI benchmarks, performance tool, HPC and deep learning application. • Experiments with different architectures (x86 and aarch64) and processors including Intel Xeon Gold, AMD Zen 2, and Arm A64FX. [ABSTRACT FROM AUTHOR]

Theoretical analysis for an online measurement of the stack gas flow velocity based on the optical scintillation method with a structure of two parallel optical paths is performed. The causes of optical scintillation in a stack are first introduced. Then, the principle of flow velocity measurement and its mathematical expression based on cross correlation of the optical scintillation are presented. The field test results show that the flow velocity measured by the proposed technique in this article is consistent with the value tested by the Pitot tube. It verifies the effectiveness of this method. Finally, by use of the structure function of logarithmic light intensity fluctuations, the theoretical explanation of optical scintillation spectral characteristic in low frequency is given. The analysis of the optical scintillation spectrum provides the basis for the measurement of the stack gas flow velocity and particle concentration simultaneously. [ABSTRACT FROM AUTHOR]

Electron impact excitation cross sections from the ground state and the lowest metastable state 5p56sJ = 2 to the excited states of the 5p57p configuration of xenon are calculated systematically using the fully relativistic distorted wave method. Special attention is paid to the configuration interaction effects in the wave-function expansion of target states. The results are in good agreement with the recent experimental data by Jung et al. [Phys. Rev. A 80 (2009) 062708] over the measured energy range. These accurate theoretical results can be used in the modeling and diagnosis of plasmas containing xenon. [ABSTRACT FROM AUTHOR]

The transition energies and electric dipole (E1) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac—Fock (MCDF) method. In the calculations, the contributions from Breit interaction and quantum electrodynamics (QED) effects (vacuum polarization and self-energy), as well as nuclear finite mass and volume effects, are taken into account. The calculated transition energies and rates are found to be in good agreement with other experimental and theoretical results. The accuracy of the results is estimated and discussed. Furthermore, we calculated the transition energies of the same lines radiating from the decaying transitions of the K-, L-, and M-shell hole states of Np ions with the charge states Np1+ to Np6+ for the first time. We found that for a specific line, the corresponding transition energies relating to all the Np ions are almost the same; it means the outermost electrons have a very small influence on the inner-shell transition processes. [ABSTRACT FROM AUTHOR]

Electron impact excitation cross sections from the ground state to the individual magnetic sublevels of 1s2p3,1P1 states in high-temperature dense plasmas are calculated for highly charged He-like Fe24+ ions by using a fully relativistic distorted-wave method. The Debye—Hückel screening model is used to screen the projectile electron from the nucleus and target electrons. The linear polarization degrees for these lines are obtained. It is found that the cross sections at all incident energies decrease with the increase of the screening for these excitations. The influence of screening on linear polarization degrees of the 1P1 line is very small. The linear polarization degrees of 3P1 line decrease sharply at low incident energy with the increase of the screening. [ABSTRACT FROM AUTHOR]

This review places modern research developments in vascular mechanobiology in the context of hemodynamic phenomena in the cardiovascular system and the discrete localization of vascular disease. The modern origins of this field are traced, beginning in the 1960s when associations between flow characteristics, particularly blood flow-induced wall shear stress, and the localization of atherosclerotic plaques were uncovered, and continuing to fluid shear stress effects on the vascular lining endothelial cells (ECs), including their effects on EC morphology, biochemical production, and gene expression. The earliest single-gene studies and genome-wide analyses are considered. The final section moves from the ECs lining the vessel wall to the smooth muscle cells and fibroblasts within the wall that are fluid mechanically activated by interstitial flow that imposes shear stresses on their surfaces comparable with those of flowing blood on EC surfaces. Interstitial flow stimulates biochemical production and gene expression, much like blood flow on ECs. [ABSTRACT FROM AUTHOR]

The clinical features and risk factors for recurrence of Kawasaki disease (KD) remain unclear. In order to summarize clinical features of recurrent KD and identify risk factors associated with recurrence, we conducted a retrospective review of the medical records of consecutive cases of KD from January 2002 to December 2010. Demographic, clinical, laboratory, and echocardiographic data were analyzed. The maximum coronary artery Z score normalized against body surface area was assessed using coronary artery diameters. At the first onset of recurrent KD, children had longer durations of fever before intravenous immunoglobulin (IVIG) treatment and higher levels of alanine aminotransferase, serum aspartate aminotransferase (AST), and lower hemoglobin levels than those with a single episode of KD. Multivariate logistic regression analysis showed that long durations of fever before IVIG treatment, high AST levels, and reduced hemoglobin levels were significantly associated with recurrent KD. Ten of the 22 recurrent KD children had coronary artery complications during the first onset episode, and six (60 %) of these also had coronary artery complications during the recurrence. Children with longer durations of fever, lower hemoglobin levels, and higher AST levels may be at increased risk for KD and coronary artery complications are more likely to occur in children with recurrent KD if they were present during the first episode. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) has exhibited effcacy at preventing the progression of pulmonary hypertension (PH); however, the exact mechanism is not completely clear. The aim of the present study was to assess whether this protective effect was mediated by the upregulation of circulating endothelial progenitor cells (EPCs) via the nitric oxide (NO) system. PH was induced in male Sprague-Dawley (SD) rats by the administration of a single subcutaneous injection of monocrotaline (MCT). The rats were treated with recombinant human G-CSF (rhG-CSF, 50 µg/kg/day) by subcutaneous injection from day fve to day seven subsequent to the injection of MCT. Nω-nitro-L-arginine methyl ester (L-NAME, 4 mg/kg/day) was intragastrically administered in addition to rhG-CSF as a negative intervention. The changes in hemodynamics and histology, the number and function of circulating EPCs and the concentration of plasma NO were evaluated. With the occurrence of PH in the rat model, the number and function of circulating EPCs were demonstrated to be markedly downregulated. Moreover, a reduced plasma concent rat ion of NO was observed, which was positively correlated with the number of circulating EPCs. Administration of rhG-CSF elevated the plasma level of NO, upregulated the number and function of circulating EPCs and effectively improved pulmonary hemodynamics and vascular reconstruction. Furthermore, the positive correlation between the levels of plasma NO and circulating EPCs was also observed in the rhG-CSF treatment group. However, the protective effect of rhG-CSF in PH was attenuated by L-NAME, which mediated the downregulation of NO and the EPCs. Thus, the present study suggests that G-CSF may attenuate the progression of MCT-induced PH by improving vascular injury repair mechanisms via the NO-mediated upregulation of EPCs. [ABSTRACT FROM AUTHOR]

Abstract: This work presents how water containing cyclopentane (CP) can facilitate the recovery of methane from the CH4/N2 coal mine gas mixture through hydrate crystallization. Gas hydrate formed in the CH4/N2/CP/H2O system has more favorable equilibrium conditions than that formed in pure water with the same gas mixture. The incipient equilibrium conditions at 4.0 and 13.0wt% CP were measured and are reported. The dynamics of hydrate formation using a 30mol% CH4/N2 gas mixture were studied at 283.4K, two CP concentrations (4.0 and 13.0wt%) and at 2.6 and 3.8MPa. These hydrate formation pressures correspond to 2.3 and 3.5MPa overpressures (driving forces) respectively. It was found that CH4 is preferentially incorporated into the hydrate crystal compared to N2. However, N2 competes with CH4 to enter the hydrate crystal at the higher driving force. The CH4 recovery substantially increases as the CP concentration is increased from 4.0 to 13.0wt%. The experimental condition of 283.4K, 2.6MPa, and 13.0wt% CP is preferred for the separation of CH4 from the 30mol% CH4/N2 gas mixture. The CH4 recovery obtained at this condition is approximately 46.1% and the corresponding CH4 content in the hydrate is 47.2mol%. A methane-rich stream (72mol% CH4/N2) is obtained after two stages of gas hydrate formation in the presence of cyclopentane. [Copyright &y& Elsevier]

The angular distribution and polarization of the x-ray photoemission of highly charged helium-like ions is studied following the K-LL dielectronic recombination of initially hydrogen-like ions. Calculation is carried out within the framework of the density matrix theory combined with the multiconfiguration Dirac-Fock approach. Attention is paid to magnetic sublevel alignment in the resonant intermediate state and to its nonuniform radiative decay processes. It is shown that the Breit interaction between the incident and target electrons plays a significant role for the alignment of the resonant state and thus causes a substantial change in the x-ray emission characteristic, when compared to the incorporation of only the (non-relativistic) Coulomb interaction. The most prominent difference in alignment parameter is found in the 2s2p1/2 J = 1 resonant state for a wide range of atomic numbers from 9 to 92. For this resonant state of helium-like ions, the Breit interaction becomes significant for ions with nuclear charge Z ~ 30 already. [ABSTRACT FROM AUTHOR]

In this paper, a simple theoretical model is developed to describe the transmission of force from interstitial fluid flow to the surface of a cell covered by a proteoglycan / glycoprotein layer (glycocalyx) and embedded in an extracellular matrix. Brinkman equations are used to describe flow through the extracellular matrix and glycocalyx layers and the solid mechanical stress developed in the glycocalyx by the fluid flow loading is determined. Using reasonable values for the Darcy permeability of extracellular matrix and glycocalyx layers and interstitial flow velocity, we are able to estimate the fluid and solid shear stresses imposed on the surface of embedded vascular, cartilage and tumor cells in vivo and in vitro. The principal finding is that the surface solid stress is typically one to two orders of magnitude larger than the surface fluid stress. This indicates that interstitial flow shear stress can be sensed by the cell surface glycocalyx, supporting numerous recent observations that interstitial flow can induce mechanotransduction in embedded cells. This study may contribute to understanding of interstitial flow-related mechanobiology in embryogenesis, tumorigenesis, tissue physiology and diseases and has implications in tissue engineering. [ABSTRACT FROM AUTHOR]

In this work, the phase equilibrium conditions of gashydrate formedusing the gas mixture of mole fractions 0.3 CH4+ 0.6 N2+ 0.1 O2in the presence of cyclopentane or cyclohexanewere measured and reported in the temperature range of (277.4 to 293.1)K and in the pressure range of (0.89 to 4.87) MPa. The mass fractionof cyclopentane or cyclohexane added into the aqueous solution was w= 0.07. It is found that the equilibrium conditions ofgas hydrate formed at the 0.07 mass fraction of cyclopentane or cyclohexaneare shifted to high temperatures and low pressures as compared tothose obtained using the same gas mixture in pure water. Moreover,the mole fraction of CH4incorporated into the hydratephase is increased to approximately 0.5, which is higher than thatin the original gas mixture. [ABSTRACT FROM AUTHOR]

In this work, tetra-n-butyl ammoniumbromide (TBAB) semiclathrate hydrate was employed in a batch operationto separate CH4from low-concentration coal mine methane(CMM) gas with a mole composition of 30% CH4,60% N2, and 10% O2. TBAB semiclathrate hydrate formedfrom the low-concentration CMM gas has more favorable incipient equilibriumconditions than gas hydrates formed from the same gas mixture. Theexperiments were carried out at a fixed pressure of 4.0 MPa, threeTBAB mole concentrations of 0.29, 0.62, and 1.38 %, and in the temperaturerange of 274.75–283.35 K. The effects of TBAB concentrationsand subcoolings (ΔTsub) on CH4separation from the low-concentration CMM gas were investigated.The results indicated that CH4was preferentially incorporatedinto the hydrate crystals rather than N2and O2in the presence of TBAB. The experimental conditions of the TBABconcentration of 1.38%, 4.0 MPa, and ΔTsub= 7.0 K were most favorable for TBAB semiclathrate hydrateto separate CH4from the low-concentration CMM gas. TheCH4recovery obtained at these conditions was approximately27%. Compared with CH4content in the low-concentrationCMM gas, the mole fraction of CH4in TBAB semiclathratehydrate was increased to 41%. [ABSTRACT FROM AUTHOR]

Non-Hodgkin's lymphoma (NHL) remains the second most common malignant complication in patients with human immunodeficiency virus (HIV) infection. Even though NHL is commonly chemosensitive to primary treatment, failure or relapse still occurs in a large number of patients. We conducted this retrospective study to evaluate the efficacy and safety of gemcitabine, dexamethasone, and cisplatin (GDP) for relapsed or refractory AIDS-related NHL (AIDS-NHL). Forty-eight patients with relapsed or refractory AIDS-NHL were treated with intravenous combination chemotherapy with GDP. The overall objective response rate was 54.1 % (95 % confidence interval, CI, 40.1-68.3 %), with 10 complete responses and 16 partial responses. The 2-year overall survival rate (OS) was 70.8 % (95 % CI 58.0-83.7 %), and the 5-year OS was 41.7 % (95 % CI 27.7-55.6 %). The 2-year progression-free survival rate (PFS) was 37.5 % (95 % CI 23.8-51.2 %), and the 5-year PFS was 25.0 % (95 % CI 12.8-37.3 %). The median progression-free survival was 8.8 months (95 % CI 0-20.3 months), and the median overall survival was 40.6 months (95 % CI 22.6-58.6 months). Patients with B cell tumors who relapsed but had no B symptoms were clinical stage I/II, had infiltration fewer than two extranodal sites, had CD4 counts >200 cells/μL, and had lactate dehydrogenase (LDH) less than the upper limit of normal benefited from GDP. The level of LDH had a significant impact on the response rate to chemotherapy with GDP ( P = 0.015). Myelosuppression was the main side effect; the incidence of grade 3-4 anemia was 8.3 %; leukopenia, 37.5 %; and thrombocytopenia, 48.3 %. Univariate and multivariate analyses were performed to determine variables for OS and PFS. This study confirms that GDP is an effective and safe salvage regimen in relapsed or refractory AIDS-NHL, was associated with modest declines in CD4 lymphocyte counts, and did not promote HIV-1 viral replication. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, electrodeposition of relatively uniform hierarchical Ag nanostructures (the RSD of size is about 28.8%) on ITO glass has been achieved via utilizing low precursor concentration and complexing agent without any surfactant. The RSD of SERS intensity (rhodamine 6G, R6G) for 1651cm−1 band is about 14.9% and the detectable concentration of R6G can be 10−10 M at least, indicating the hierarchical Ag nanostructures on ITO glass good candidate for reproducible and sensitive SERS application. [Copyright &y& Elsevier]

Objective: To evaluate through retrospective analysis the efficacy and toxicity of combination chemotherapy with etoposide, vincristine, doxorubin and dexamethasone (EVAD) as second-line therapy in patients with advanced AIDS-related Kaposi's sarcoma (AIDS-KS) after failure of first-line chemotherapy. Methods: Eighty-eight patients with poor-risk AIDS-KS were treated intravenously with combination chemotherapy with EVAD; etoposide at a dose of 100 mg/m on three consecutive days, vincristine 1.4 mg/m with a maximum single dosage of 2.0 mg on day one, doxorubicin 30 mg/m on day one and dexamethasone 40 mg on three consecutive days, with a three week cycle. All eligible patients had relapsed or progressed after prior two to six cycles of combination chemotherapy with doxorubicin, bleomycin and vincristine (ABV) or bleomycin and vincristine (BV). Results: Assessment of the response of all the patients was made. The overall objective response rate was 59.1% (95% CI 48.83-69.37%), with five complete responses and 47 partial responses. Twenty-six cases of stable disease and 10 of progressive disease were observed in the remaining patients. The median follow-up period was 27 months (range 8-52 months). The median time to progression was 6.80 months (95% CI 2.04-11.56 months), and the median overall survival was 14.24 months (95% CI 10.26-18.22 months). Leucopenia was seen in 92.0% of patients, of which 20 patients had grade 3 and 12 had grade 4. Conclusions Combination chemotherapy with EVAD offers a new, active and safe therapeutic approach for the treatment of advanced AIDS-related KS. [ABSTRACT FROM AUTHOR]

Background: Premature cervical remodeling/ripening is believed to contribute to preterm delivery (PTD), the leading cause of perinatal morbidity and mortality. Despite considerable research, the causes of term and PTD remain unclear, and there is no effective treatment for PTD. We previously demonstrated that complement activation plays a causative role in cervical remodeling that leads to PTD in mice. Methodology/Principal Findings: Here we found that complement activation is not required for the physiological process that leads to term delivery in mice. Neither increased C3 cervical deposition nor increased C3a and C5a serum levels were observed at term. In addition, macrophages infiltration was found in PTD in contrast to term delivery were no leukocytes were found. Despite the different role of complement and different cellular effector cells, PTD and term delivery share a common dowsntream pathway characterized by increased metalloproteinases (MMPs) release and increased collagen degradation. However, different sources of MMPs were identif ied. Macrophages are the source of MMPs in PTD while cervical fibroblasts and columnar epithelial cells synthesize MMPs at term delivery. A dramatic diminution in serum progesterone levels precedes parturition at term but not in PTD, suggesting that progesterone withdrawal initiates cervical remodeling at term. On the other hand, MMPs release in PTD is triggered by C5a. Conclusion and Significance: In conclusion, preterm and term cervical remodeling occur through the same mechanism but they are initiated by different mediators and effector cells. That complement activation is required for PTD but not for the physiological process that leads to term delivery, suggests that complement is a potential specific biomarker and selective target to prevent PTD and thus avert neonatal mortality and morbidity. [ABSTRACT FROM AUTHOR]

The solubility of chlorobenzene was measured in subcritical water using a fused silica capillary reactor (FSCR) combined with a microscope recorder system to capture the images and identify the temperature of total dissolution. The solubility of chlorobenzene was found to vary between 43.5 mg g–1in water at 173.3 °C and 71.4 mg g–1in water at 266.9 °C, increasing linearly with temperature. A new approximation model was developed to predict the solubility of chlorobenzene in subcritical water at elevated temperatures. This visualization in the FSCR method does not require sampling and subsequent analysis, and it has a great potential for the solubility determinations of other organic or inorganic materials. [ABSTRACT FROM AUTHOR]

Background: Glioma cells are exposed to elevated interstitial fluid flow during the onset of angiogenesis, at the tumor periphery while invading normal parenchyma, within white matter tracts, and during vascular normalization therapy. Glioma cell lines that have been exposed to fluid flow forces in vivo have much lower invasive potentials than in vitro cell motility assays without flow would indicate. Methodology/Principal Findings: A 3D Modified Boyden chamber (Darcy flow through collagen/cell suspension) model was designed to mimic the fluid dynamic microenvironment to study the effects of fluid shear stress on the migratory activity of glioma cells. Novel methods for gel compaction and isolation of chemotactic migration from flow stimulation were utilized for three glioma cell lines: U87, CNS-1, and U251. All physiologic levels of fluid shear stress suppressed the migratory activity of U87 and CNS-1 cell lines. U251 motility remained unaltered within the 3D interstitial flow model. Matrix Metalloproteinase (MMP) inhibition experiments and assays demonstrated that the glioma cells depended on MMP activity to invade, and suppression in motility correlated with downregulation of MMP-1 and MMP-2 levels. This was confirmed by RT-PCR and with the aid of MMP-1 and MMP-2 shRNA constructs. Conclusions/Significance: Fluid shear stress in the tumor microenvironment may explain reduced glioma invasion through modulation of cell motility and MMP levels. The flow-induced migration trends were consistent with reported invasive potentials of implanted gliomas. The models developed for this study imply that flow-modulated motility involves mechanotransduction of fluid shear stress affecting MMP activation and expression. These models should be useful for the continued study of interstitial flow effects on processes that affect tumor progression. [ABSTRACT FROM AUTHOR]

Background: Interstitial flow directly affects cells that reside in tissues and regulates tissue physiology and pathology by modulating important cellular processes including proliferation, differentiation, and migration. However, the structures that cells utilize to sense interstitial flow in a 3-dimensional (3D) environment have not yet been elucidated. Previously, we have shown that interstitial flow upregulates matrix metalloproteinase (MMP) expression in rat vascular smooth muscle cells (SMCs) and fibroblasts/myofibroblasts via activation of an ERK1/2-c-Jun pathway, which in turn promotes cell migration in collagen. Herein, we focused on uncovering the flow-induced mechanotransduction mechanism in 3D. Methodology/Principal Findings: Cleavage of rat vascular SMC surface glycocalyx heparan sulfate (HS) chains from proteoglycan (PG) core proteins by heparinase or disruption of HS biosynthesis by silencing N-deacetylase/Nsulfotransferase 1 (NDST1) suppressed interstitial flow-induced ERK1/2 activation, interstitial collagenase (MMP-13) expression, and SMC motility in 3D collagen. Inhibition or knockdown of focal adhesion kinase (FAK) also attenuated or blocked flow-induced ERK1/2 activation, MMP-13 expression, and cell motility. Interstitial flow induced FAK phosphorylation at Tyr925, and this activation was blocked when heparan sulfate proteoglycans (HSPGs) were disrupted. These data suggest that HSPGs mediate interstitial flow-induced mechanotransduction through FAK-ERK. In addition, we show that integrins are crucial for mechanotransduction through HSPGs as they mediate cell spreading and maintain cytoskeletal rigidity. Conclusions/Significance: We propose a conceptual mechanotransduction model wherein cell surface glycocalyx HSPGs, in the presence of integrin-mediated cell-matrix adhesions and cytoskeleton organization, sense interstitial flow and activate the FAK-ERK signaling axis, leading to upregulation of MMP expression and cell motility in 3D. This is the first study to describe a flow-induced mechanotransduction mechanism via HSPG-mediated FAK activation in 3D. This study will be of interest in understanding the flow-related mechanobiology in vascular lesion formation, tissue morphogenesis, cancer cell metastasis, and stem cell differentiation in 3D, and also has implications in tissue engineering. [ABSTRACT FROM AUTHOR]

Background: During vascular injury, vascular smooth muscle cells (SMCs) and fibroblasts/myofibroblasts (FBs/MFBs) are exposed to altered luminal blood flow or transmural interstitial flow. We investigate the effects of these two types of fluid flows on the phenotypes of SMCs and MFBs and the underlying mechanotransduction mechanisms. Methodology/Principal Findings: Exposure to 8 dyn/cm2 laminar flow shear stress (2-dimensional, 2-D) for 15 h significantly reduced expression of a-smooth muscle actin (α-SMA), smooth muscle protein 22 (SM22), SM myosin heavy chain (SM-MHC), smoothelin, and calponin. Cells suspended in collagen gels were exposed to interstitial flow (1 cmH2O, ∼0.05 dyn/cm2, 3-D), and after 6 h of exposure, expression of SM-MHC, smoothelin, and calponin were significantly reduced, while expression of α-SMA and SM22 were markedly enhanced. PD98059 (an ERK1/2 inhibitor) and heparinase III (an enzyme to cleave heparan sulfate) significantly blocked the effects of laminar flow on gene expression, and also reversed the effects of interstitial flow on SM-MHC, smoothelin, and calponin, but enhanced interstitial flow-induced expression of a-SMA and SM22. SMCs and MFBs have similar responses to fluid flow. Silencing ERK1/2 completely blocked the effects of both laminar flow and interstitial flow on SMC marker gene expression. Western blotting showed that both types of flows induced ERK1/2 activation that was inhibited by disruption of heparan sulfate proteoglycans (HSPGs). Conclusions/Significance: The results suggest that HSPG-mediated ERK1/2 activation is an important mechanotransduction pathway modulating SMC marker gene expression when SMCs and MFBs are exposed to flow. Fluid flow may be involved in vascular remodeling and lesion formation by affecting phenotypes of vascular wall cells. This study has implications in understanding the flow-related mechanobiology in vascular lesion formation, tumor cell invasion, and stem cell differentiation. [ABSTRACT FROM AUTHOR]

The migration of vascular smooth muscle cells (SMCs) and fibroblasts into the intima after vascular injury is a central process in vascular lesion formation. The elevation of transmural interstitial flow is also observed after damage to the vascular endothelium. We have previously shown that interstitial flow upregulates matrix metalloproteinase1 (MMP1) expression, which in turn promotes SMC and fibroblast migration in collagen I gels. In this study, we investigated further the mechanism of flow-induced MMP-1 expression. An ERK1/2 inhibitor PD-98059 completely abolished interstitial flow-induced SMC migration and MMP1 expression. Interstitial flow promoted ERK1/2 phosphorylation, whereas PD-98059 abolished flow-induced activation. Silencing ERK 1/2 completely abolished MMP1 expression and SMC migration. In addition, interstitial flow increased the expression of activator protein-1 transcription factors (c-Jun and c-Fos), whereas PD-98059 attenuated flow-induced expression. Knocking down c-jun completely abolished flow-induced MMP1 expression, whereas silencing c-fos did not affect MMP-1 expression. Taken together, our data indicate that interstitial flow induces MMP-l expression and SMC migration in collagen I gels via an ERK1/2-dependent and c-Jun-mediated mechanism and suggest that interstitial flow, ERK1/2 MAPK, c-Jun, and MMP-1 may play important roles in SMC migration and neointima formation after vascular injury. [ABSTRACT FROM AUTHOR]

The molecular combing technique was used to dissociate the nanostructural units of starch granules from the starch fragments after a gelatinization process. With the help of atomic force microscopy (AFM), we observed that some nanostructural chains were just flowing out of the granules. It proves that there are substantive nanostructural units in the starch granules, a phenomenon not previously observed, so these nanostructural units were defined as suspected intermediates. Furthermore, we conclude that blocklets of starch granules are formed through twisting or distortion of nanochains. [ABSTRACT FROM AUTHOR]

Neointima formation often occurs in regions where the endothelium has been damaged and the transmural interstitial flow is elevated. Vascular smooth muscle cells (SMCs) and fibroblasts/myofibroblasts (FBs/MFBs) contribute to intimal thickening by migrating from the media and adventitia into the site of injury. In this study, for the first time, the direct effects of interstitial flow on SMC and FB/MFB migration were investigated in an in vitro three-dimensional system. Collagen I gels were used to mimic three-dimensional extracellular matrix (ECM) for rat aortic SMCs and FBs/MFBs. Exposure to interstitial flow induced by 1 cmH2O pressure differential (shear stress, ∼0.05 dyn/cm2 flow velocity, ∼0.5 p.m/s; and Darcy permeability, ∼10-11 cm2) substantially enhanced cell motility. Matrix metalloproteinase (MMP) inhibitor (GM-6001) abolished flow-induced migration augmentation, which suggested that the enhanced motility was MMP dependent. The upregulation of MMP-1 played a critical role for the flow-enhanced motility, which was further confirmed by silencing MMP-1 gene expression. Longer exposures to higher flows suppressed the number of migrated cells, although MMP-1 gene expression remained high. This suppression was a result of both flow-induced tissue inhibitor of metalloproteinase-1 upregulation and increased apoptotic and necrotic cell death. Interstitial flow did not affect MMP-2 gene expression or activity in the collagen I gel for any cell type. Our findings shed light on the mechanism by which vascular SMCs and FBs/MFBs contribute to intimal thickening in regions of vascular injury where interstitial flow is elevated. [ABSTRACT FROM AUTHOR]

Abstract: We numerically investigate the complete chaotic synchronization mechanism of polarization mode of VCSEL with anisotropic optical feedback. Firstly, the synchronization quality of the x-linear polarization (LP) mode and the y-LP mode are both periodically changed with the angle θ between the polarizer and the light axes. Secondly, in a enough large scale region of the feedback coefficient and the injection current, where each LP mode can obtained good synchronization quality when the angle θ exists in the former half period region and the injection current is fixed at a certain value, which is over the threshold current. Under this condition, their synchronization quality is independent of the polarization states. By contrast, in the latter half period region of the angle θ where each LP mode can be obtained very instable and inferior synchronized quality. At last, the robustness of the synchronization scheme is sensitive to the internal and external parameter mismatch between the transmitter–VCSEL and the receiver–VCSEL. [Copyright &y& Elsevier]

A variety of proteases have been implicated in prostate cancer (PC) bone metastasis, but the individual contributions of these enzymes remain unclear. Urokinase-type plasminogen activator (uPA), a serine protease, can activate plasminogen and stimulate signaling events on binding its receptor uPAR. In the present study, we investigated the functional role of PC cell--associated uPA in intraosseous tumor growth and bone matrix degradation. Using a severe combined immunodeficient--human mouse model, we found that PC3 cells were the major source of uPA in the experimental bone tumor. Injection of uPA-silenced PC3 cells in bone xenografts resulted in significant reduction of bone tumor burdens and protection of trabecular bones from destruction. The suppressed tumor growth was associated with the level of uPA expression but not with its activity. An increase in the expression of PAI-1, the endogenous uPA inhibitor, was found during in vitro tumor-stromal interactions. Up-regulation of PAI-1 in bone stromal cells and preosteoclasts/osteoblasts was due to soluble factor(s) released by PC cells, and the enhanced PAI-1 expression in turn stimulated PC cell migration. Our results indicate that both tumor-derived uPA and tumor-stroma-induced PAI-1 play important roles in intraosseous metastatic PC growth through regulation of a uPA-uPAR-PAI-1 axis by autocrine/paracrine mechanisms. [ABSTRACT FROM AUTHOR]