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Ionic liquids (ILs) are a diverse class of solvents which can be selected for task-specific properties, making them attractive alternatives to traditional solvents. To tailor ILs for specific biological applications, it is necessary to understand the structure–property relationships of ILs and their interactions with cells. Here, a selection of carboxylate anion-based ILs were investigated as cryoprotectants, which are compounds added to cells before freezing to mitigate lethal freezing damage. The cytotoxicity, cell permeability, thermal behavior, and cryoprotective efficacy of the ILs were assessed with two model mammalian cell lines. We found that the biophysical interactions, including permeability of the ILs, were influenced by considering the IL pair together, rather than as single species acting independently. All of the ILs tested had high cytotoxicity, but ethylammonium acetate demonstrated good cryoprotective efficacy for both cell types tested. These results demonstrate that despite toxicity, ILs may be suitable for certain biological applications. It also demonstrates that more research is required to understand the contribution of ion pairs to structure–property relationships and that knowing the behavior of a single ionic species will not necessarily predict its behavior as part of an IL.

We investigated phase constitutions, ferroelectric (FE), and magnetic characteristics of BiFeO3 (BFO) films with Tb substitution. Bi1-xTbxFeO3 (BTFO) ( ${x}$ = 0.00–0.15) thin films were prepared on the Pt-buffered glass substrates by pulsed laser deposition (PLD). BTFO films with ${x}$ = 0.00–0.15 were confirmed to mainly consist of the perovskite phase. The structure in the studied films is transformed from rhombohedral for ${x}$ = 0.00 to pseudo-cubic for ${x}$ = 0.05–0.10, and orthorhombic for ${x}$ = 0.15. The studied BTFO polycrystalline films exhibit the desired FE and ferromagnetic properties at the same time. The remanent polarization ( $2P_{r}$ ) of $157 ~\mu \text{C}$ /cm2 and electrical coercive field ( $E_{c}$ ) of 485 kV/cm are obtained for BTFO films at ${x}$ = 0.05. Besides, the saturation magnetization ( $M_{s}$ ) of 15.0 emu/cm3 is found for $x$ = 0.05 film. The enhanced $M_{s}$ with Bi0.95Tb0.05FeO3 is due to the magnetic moment of the doped Tb $^{3+}$ ion in addition to the suppressed spiral spin configuration. The result of this work indicates that the radius and magnetic moment of the Tb $^{3+}$ ions play a critical role in the structural evolution, refined microstructure, and therefore, enhanced multiferroic (MF) properties for Tb-substituted BFO polycrystalline films.

We investigated the fluorescence kinetics of LH2 complexes from Marichromatium purpuratum, the cryo-EM structure of which has been recently elucidated with 2.4 Å resolution. The experiments have been carried out as a function of the excitation density by varying both the excitation fluence and the repetition rate of the laser excitation. Instead of the usual multiexponential fitting procedure, we applied the less common phasor formalism for evaluating the transients because this allows for a model-free analysis of the data without a priori knowledge about the number of processes that contribute to a particular decay. For the various excitation conditions, this analysis reproduces consistently three lifetime components with decay times below 100 ps, 500 ps, and 730 ps, which were associated with the quenched state, singlet-triplet annihilation, and fluorescence decay, respectively. Moreover, it reveals that the number of decay components that contribute to the transients depends on whether the excitation wavelength is in resonance with the B800 BChl amolecules or with the carotenoids. Based on the mutual arrangement of the chromophores in their binding pockets, this leads us to conclude that the energy transfer pathways within the LH2 complex of this species differ significantly from each other for exciting either the B800 BChl molecules or the carotenoids. Finally, we speculate whether the illumination with strong laser light converts the LH2 complexes studied here into a quenched conformation that might be related to the development of the non-photochemical quenching mechanism that occurs in higher plants.

The ability to predict cell-permeable candidate molecules has great potential to assist drug discovery projects. Large molecules that lie beyond the Rule of Five (bRo5) are increasingly important as drug candidates and tool molecules for chemical biology. However, such large molecules usually do not cross cell membranes and cannot access intracellular targets or be developed as orally bioavailable drugs. Here, we describe a random forest (RF) machine learning model for the prediction of passive membrane permeation rates developed using a set of over 1000 bRo5 macrocyclic compounds. The model is based on easily calculated chemical features/descriptors as independent variables. Our random forest (RF) model substantially outperforms a multiple linear regression model based on the same features and achieves better performance metrics than previously reported models using the same underlying data. These features include: (1) polar surface area in water, (2) the octanol-water partitioning coefficient, (3) the number of hydrogen-bond donors, (4) the sum of the topological distances between nitrogen atoms, (5) the sum of the topological distances between nitrogen and oxygen atoms, and (6) the multiple molecular path count of order 2. The last three features represent molecular flexibility, the ability of the molecule to adopt different conformations in the aqueous and membrane interior phases, and the molecular “chameleonicity.” Guided by the model, we propose design guidelines for membrane-permeating macrocycles. It is anticipated that this model will be useful in guiding the design of large, bioactive molecules for medicinal chemistry and chemical biology applications.

This study presents the diversity of mosquitoes collected from communes, endemic with malaria and dengue, located in Khanh Hoa and Binh Phuoc Provinces, Vietnam. A total of 10,288 mosquitoes were collected in the village and forested sites using standard larval dippers, cow-baited traps, ultra-violet light traps, and mechanical aspirators. Mosquito taxa were identified morphologically and species complexes/groups were further characterized molecularly. Five genera of mosquitoes were morphologically identified: Anopheles Meigen(21 species), Aedes Meigen(2 species), Culex Linnaeus(5 species), Mansonia Blanchardsp., and Armigeres Theobaldsp. The PCR-based identification methods allowed the distinction of members of Maculatus Group, Funestus Group, and Dirus Complex; and DNA barcodes enabled the further identification of the Barbirostris Complex. Data reported here include the first report of An. saeungaeTaai & Harbach and An. wejchoochoteiTaai & Harbach from Vietnam, and re-emphasizes the significance of using molecular data in an integrated systematic approach to identify cryptic species and better understand their role in disease transmission.

Water is a unique solvent that is ubiquitous in biology and present in a variety of solutions, mixtures, and materials settings. It therefore forms the basis for all molecular dynamics simulations of biological phenomena, as well as for many chemical, industrial, and materials investigations. Over the years, many water models have been developed, and it remains a challenge to find a single water model that accurately reproduces all experimental properties of water simultaneously. Here, we report a comprehensive comparison of structural and dynamic properties of 30 commonly used 3-point, 4-point, 5-point, and polarizable water models simulated using consistent settings and analysis methods. For the properties of density, coordination number, surface tension, dielectric constant, self-diffusion coefficient, and solvation free energy of methane, models published within the past two decades consistently show better agreement with experimental values compared to models published earlier, albeit with some notable exceptions. However, no single model reproduced all experimental values exactly, highlighting the need to carefully choose a water model for a particular study, depending on the phenomena of interest. Finally, machine learning algorithms quantified the relationship between the water model force field parameters and the resulting bulk properties, providing insight into the parameter–property relationship and illustrating the challenges of developing a water model that can accurately reproduce all properties of water simultaneously.

Ionic liquid containing solvent systems are candidates for very large compositional space exploration due to the immensity of the possible combination of ions and molecular species. The prediction of key properties of such multicomponent solvent systems plays a vital role in the design and optimization of their structures for specific applications. In this study, we have explored two machine learning algorithms for predicting the surface tension and liquid nanostructure of solvents containing a protic ionic liquid (PIL) with water and excess acid or base present. Machine learning algorithms of multiple linear regression (MLR) and Bayesian regularized artificial neural networks (ANNs) were used to develop semiempirical structure–property models for the data set, which was comprised of 207 surface tension and 80 liquid nanostructure data elements which we previously reported (Phys. Chem. Chem. Phys.2019, 21, 6810–6827). On the basis of the models, the significance levels for the impact of the alkyl chain length and the presence of hydroxyl groups on cation, type of anion, nonstoichiometry, and presence of water were elucidated. Both models are statistically applicable for designing new PIL containing solvent systems. Furthermore, the generated models were used to create response-surface plots, for both surface tension and liquid nanostructure, interpolated across the compositional space. An additional surface tension data set with 18 new data points within the same compositional space was used to test the prediction ability of models, and the results showed all of the models were successful for prediction. These machine learning approaches are highly suited to the development of structure–property relationships for ionic liquids and particularly for the increasing use of ionic liquid–molecular solvent mixtures.

An analytical wave representation is derived to express the asymmetric elliptic vortex beams generated by using an astigmatic mode converter to transform the asymmetric Hermite–Gaussian modes. The effect of the spatial asymmetry on the elliptic vortex beam can be straightforwardly considered in the analytical wave representation. A detailed comparison with experimental intensity patterns and phase structures is made. The good agreement between experimental results and theoretical analyses confirms the characterization and generation of the asymmetric elliptic vortex beams.

A general integral formula is analytically derived to represent the wave function of elliptical vortex modes. The derived formula can be straightforwardly employed to take account of spatial damping to explore vortex structure. Spatial damping is found to cause the central degenerate singularity of the circular vortex mode to be split into several singularities with different topological charges. For the non-circular vortex beam, the influence of spatial damping on the distribution of singularities is not significant. Theoretical analyses are confirmed to agree very well with the experimental measurements.

Aberrant protein glycosylation could be a distinct surface-marker of cancer cells that influences cancer progression and metastasis because glycosylation can regulate membrane protein folding which alters receptor activation and changes epitope exposure for antibody (Ab) recognition. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), a glycophosphoinositol-anchored protein, is a heavily glycosylated tumor antigen. However, the clinical significance and biological effect of CEACAM6 glycosylation has not been addressed in cancers. We recently developed an anti-CEACAM6 Ab (TMU) from an immune llama library which can be engineered to a single-domain (sd)Ab or a heavy-chain (HC)Ab. The TMU HCAb specifically recognized glycosylated CEACAM6 compared to the conventional antibodies. Using the TMU HCAb, we found that glycosylated CEACAM6 was a tumor marker associated with recurrence in early-stage OSCC (oral squamous cell carcinoma) patients. CEACAM6 promoted OSCC cell invasion, migration, cytoskeletal rearrangement, and metastasis via interaction with epidermal growth factor (EGF) receptor (EGFR) and enhancing EGFR activation, clustering and intracellular signaling cascades. These functions were modulated by N-acetylglucosaminyltransferase 5 (MGAT5) which mediated N-glycosylation at Asn256(N256) of CEACAM6. Finally, the TMU sdAb and HCAb treatment inhibited the migration, invasion and EGF-induced signaling in CEACAM6-overexpressing cells. In conclusion, the complex N-glycosylation of CEACAM6 is critical for EGFR signaling of OSCC invasion and metastasis. Targeting glycosylated CEACAM6 with the TMU sdAb or TMU HCAb could be a feasible therapy for OSCC.

The spectral break (fb) of magnetic fluctuations at the ion scale in the solar wind is considered to give important clue on the turbulence dissipation mechanism. Among several possible mechanisms, the most notable two are related respectively to proton thermal gyroradius ρiand proton inertial length di. The corresponding frequencies of them are fρi=VSW/(2πρi) and fdi=VSW/(2πdi), respectively, where VSWis the solar wind speed. However, no definite conclusion has been given for which one is more reasonable because the two parameters have similar value when plasma beta β∼ 1. Here we do a statistical study to see if the two ratios fb/fρiand fb/fdihave different dependence on βin the solar wind turbulence with 0.1 < β< 1.3. From magnetic measurements by the Wind spacecraft, we select 141 data sets with each one longer than 13 h. We find that the ratio fb/fdiis statistically not dependent on β, and the average value of it is 0.48 ± 0.06. However, fb/fρiincreases with increasing βclearly and is significantly smaller than fb/fdiwhen β< 0.8. These new results show that fbis statistically 0.48fdi, and the influence of βcould be negligible in the studied βrange. It indicates a preference of the dissipation mechanism associated with diin the solar wind with 0.1 < β< 0.8. Further theoretical studies are needed to give detailed explanation. The beta dependence of ion‐scale spectral break normalized to diand ρiis analyzed in beta range 0.1‐1.3Ratio between spectral break frequency and fdiis statistically 0.48 and is not dependent on betaThe result is favorable to dissipation mechanisms associated with diin the beta range of interest

It has been a long‐standing debate on the nature of Elsässer variable z−observed in the solar wind fluctuations. It is widely believed that z−represents inward propagating Alfvén waves and interacts nonlinearly with z+(outward propagating Alfvén waves) to generate energy cascade. However, z−variations sometimes show a feature of convective structures. Here we present a new data analysis on autocorrelation functions of z−in order to get some definite information on its nature. We find that there is usually a large drop on the z−autocorrelation function when the solar wind fluctuations are highly Alfvénic. The large drop observed by Helios 2 spacecraft near 0.3 AU appears at the first nonzero time lag τ= 81 s, where the value of the autocorrelation coefficient drops to 25%–65% of that at τ= 0 s. Beyond the first nonzero time lag, the autocorrelation coefficient decreases gradually to zero. The drop of z−correlation function also appears in the Wind observations near 1 AU. These features of the z−correlation function may suggest that z−fluctuations consist of two components: high‐frequency white noise and low‐frequency pseudo structures, which correspond to flat and steep parts of z−power spectrum, respectively. This explanation is confirmed by doing a simple test on an artificial time series, which is obtained from the superposition of a random data series on its smoothed sequence. Our results suggest that in highly Alfvénic fluctuations, z−may not contribute importantly to the interactions with z+to produce energy cascade. A large drop is observed on the correlation function of z−in highly Alfvenic fluctuations by Helios and WindThe autocorrelation function of an artificial random data series is shown to be similar to the observed onesz−is suggested to be composed of high‐frequency white noise and low‐frequency pseudostructures in the studied cases

Hepatocellular carcinoma (HCC) is the most common type of liver cancer. Despite the availability of several treatment strategies, resistance to chemotherapeutic agents, which limits the effectiveness of anticancer drugs, is a major problem in cancer therapy. In this study, we used a histone deacetylases inhibitor (HDACi) to establish drug-resistant HCC cells and further analyzed the molecular mechanisms underlying the development of resistance in HCC cells. Compared with the parental cells, HDACi-resistant cells showed high metastatic and pro-survival abilities. Two-dimensional electrophoresis data showed that the cofilin-1 (CFL-1) protein was altered in HDACi-resistant cells and was highly expressed in resistant cells compared with parental cells. The molecular function of CFL-1 is actin depolymerization, and it is involved in tumor metastasis. In this study, we showed that CFL-1 inhibition decreased cell migration and increased cell apoptosis in HDACi-resistant cells. We observed that HDACi induced ROS accumulation in cells and apoptosis via promotion of the CFL-1 interaction with Bax and CFL-1 translocation to the mitochondria, resulting in cytochrome Crelease. Importantly, phosphorylation of CFL-1 by activated extracellular signal-regulated kinases 1 and 2 (ERK1/2) confers strong protection against HDAC inhibitor-induced cell injury. p-CFL-1 shows a loss of affinity with Bax and will not translocate to mitochondria, stably remaining in the cytoplasm. These results indicate that phosphorylation to inactivate CFL-1 decreased the chemosensitivity to HDAC inhibitors and resulting in drug resistance of HCC cells.

A novel carbon and copper fibre knitted fabric (Cf/Cu) reinforced contact strip (Cf/Cu–C) was fabricated by pyrolytic carbon deposition and resin impregnation–carbonisation process. The interface characteristics of the composite were characterised by a scanning electron microscope and a metallographic microscope; resistivity, mechanical strength and wear properties with electric current were also investigated. The results indicated that the Cf/Cu–C material with density of 1.73 g cm− 3combined quite well between phase contacting areas for each interface. With resistivity of 10.16 μΩ m and bending strength of 123 MPa, the as prepared composite outperformed the present AR129 carbon contact strip (density, 1.70 g cm− 3, resistivity, 33 μΩ m; bending strength, 40 MPa). The wear mechanisms of Cf/Cu–C with electric current were proved to be slightly arc erosion and abrasive wear.

Halide perovskites have attracted enormous attention due to their potential applications in optoelectronics and photocatalysis. However, concerns over their instability, toxicity, and unsatisfactory efficiency have necessitated the development of lead-free all-inorganic halide perovskites. A major challenge in designing efficient halide perovskites for practical applications is the lack of effective methods for producing nanocrystals with precise size and shape control. In this work, a layered perovskite, Cs4ZnSb2Cl12(CZS), is found from calculations to exhibit size- and facet-dependent optoelectronic properties in the nanoscale, and thus, a colloidal method is used to synthesize the CZS nanoparticles with size-tunable morphologies: zero- (nanodots), one- (nanowires and nanorods), two- (nanoplates), and three-dimensional (nanopolyhedra). The growth kinetics of the CZS nanostructures, along with the effects of surface ligands, reaction temperature, and time were investigated. The optoelectronic properties of the nanocrystals varied with size due to quantum confinement effects and with shape due to anisotropy within the crystals and the exposure of specific facets. These properties could be modulated to enhance the visible-light photocatalytic performance for toluene oxidation. In particular, the 9.7 nm CZS nanoplates displayed a toluene to benzaldehyde conversion rate of 1893 μmol g–1h–1(95% selectivity), 500 times higher than the bulk synthesized CZS, and comparable with the reported photocatalysts. This study demonstrates the integration of theoretical calculations and synthesis, revealing an approach to the design and fabrication of novel, high-performance colloidal perovskite nanocrystals for optoelectronic and photocatalytic applications.

Aims. We identify high-frequency Alfvén waves propagating upward in the solar chromosphere and transition region from observation by Solar Optical Telescope (SOT) onboard Hinode.

Context.It is well known that the fast solar wind originates from coronal holes (CHs). However, the question whether it can also originate from quiet Sun regions has not yet been answered.

Aims.The structure of the solar transition region (TR) in a polar coronal hole of the Sun is studied. In particular, the detailed association of the coronal magnetic field (carpet) with the radiance patterns of the TR, when seen in various far ultraviolet (FUV) emission lines, is investigated.

Dispersed amphiphile-fatty acid systems are of great interest in drug delivery and gene therapies because of their potential for triggered release of their payload. The mesophase behavior of these systems is extremely complex and is affected by environmental factors such as drug loading, percentage and nature of incorporated fatty acids, temperature, pH, and so forth. It is important to study phase behavior of amphiphilic materials as the mesophases directly influence the release rate of the incorporated drugs. We describe a robust machine learning method for predicting the phase behavior of these systems. We have developed models for each mesophase that simultaneous and reliably model the effects of amphiphile and fatty acid structure, concentration, and temperature and that make accurate predictions of these mesophases for conditions not used to train the models.

It has recently been suggested that small-scale reconnection occurring in the chromospheric network creates high-frequency Alfvén waves, and that these waves may represent the main energy source for the heating of the solar corona and generation of the solar wind. However, if these waves exist, they will be absorbed preferentially by the minor heavy ions with low gyrofrequencies, and thus it is unclear whether there is actually enough wave energy left over for the heating and acceleration of the major solar wind ions, namely protons and alpha particles, in the extended corona after the absorption by heavy ions (Cranmer [CITE]). We have studied this problem with the multi-fluid model presented by Tu & Marsch (2001), which includes the self-consistent treatment of the damping of the waves as well as the associated acceleration and heating of the ions. We found that if the wave power density is sufficiently large, say about 1000 nT2Hz-1at 160 Hz and 2.5 $R_{\odot}$, then the wave absorption by a prominent minor ion such as O+5is small, and most of the wave energy is left for absorption by protons. This occurs because the minor ions are quickly (within several gyroperiods) accelerated and then are induced to partially surfing the waves. However, if the wave power is too low, say lower than 10 nT2Hz-1at 160 Hz and 2.5 $R_{\odot}$, then the damping of the wave power by the O+5ions is severe, and little wave energy is left for protons.

Flash point is an important property of chemical compounds that is widely used to evaluate flammability hazard. However, there is often a significant gap between the demand for experimental flash point data and their availability. Furthermore, the determination of flash point is difficult and costly, particularly for some toxic, explosive, or radioactive compounds. The development of a reliable and widely applicable method to predict flash point is therefore essential. In this paper, the construction of a quantitative structure – property relationship model with excellent performance and domain of applicability is reported. It uses the largest data set to date of 9399 chemically diverse compounds, with flash point spanning from less than −130 °C to over 900 °C. The model employs only computed parameters, eliminating the need for experimental data that some earlier computational models required. The model allows accurate prediction of flash point for a broad range of compounds that are unavailable or not yet synthesized. This single model with a very broad range of chemical and flash point applicability will allow accurate predictions of this important property to be made for a broad range of new materials.

This paper presents a theoretical analysis of thermally induced noise in sheet metal roofs. A quasistatic model of the roof behavior is developed based on roof support batten frictional forces constraining the thermal expansion and contraction of the sheeting. As a result, inplane stresses, set up in the sheeting, build up until the static frictional force limit is exceeded at one of the fasteners. At this point the sheeting slips over the batten at that fastener, the local frictional force is reduced to the dynamic frictional force limit, and a redistribution of inplane stresses and fastener forces occurs. The redistribution can cause an overload of an adjacent fastener frictional force to exceed its limit, thereby inducing another slip. The sequence will continue until all frictional forces are below the static frictional force limit. The change in deflection pattern of the roof accompanying each slip is used to estimate the noise generated. With the assumptions that the curvature strain is small relative to the thermal strain, the coefficients of friction at each batten are identical and the batten spacing is uniform, the theory may be used to derive considerable detail of the slip cascade pattern and to determine expressions for the rate of noise bursts, for the necessary temperature change to cause a roof to change from “heating” to “cooling” cycling, and for the impulsive noise level.

Management intensity critically influences the productivity and sustainability of pasture systems through modifying soil microbes, and soil carbon (C) and nutrient dynamics; however, such effects are not well understood yet in the southeastern USA. We examined the effects of grazing intensity and grass planting system on soil C and nitrogen (N) dynamics, and microbial biomass and respiration in a long-term field experiment in Goldsboro, North Carolina, USA. A split-plot experiment was initiated in 2003 on a highly sandy soil under treatments of two grass planting systems (ryegrass rotation with sorghum-sudangrass hybrid and ryegrass seeding into a perennial bermudagrass stand) at low and high grazing densities. After 4 years of continuous treatments, soil total C and N contents across the 0–30 cm soil profile were 24.7% and 17.5% higher at the high than at the low grazing intensity, likely through promoting plant productivity and C allocation belowground as well as fecal and urinary inputs. Grass planting system effects were significant only at the low grazing intensity, with soil C, N, and microbial biomass and respiration in the top 10 cm being higher under the ryegrass/bermudagrass than under the ryegrass/sorghum-sudangrass hybrid planting systems. These results suggest that effective management could mitigate potential adverse effects of high grazing intensities on soil properties and facilitate sustainability of pastureland.

Aqueous solubility is a very important physical property of small molecule drugs and drug candidates but also one of the most difficult to predict accurately. Aqueous solubility plays a major role in drug delivery and pharmacokinetics. It is believed that crystal lattice interactions are important in solubility and that including them in solubility models should improve the accuracy of the models. We used calculated values for lattice energy and sublimation enthalpy of organic molecules as descriptors to determine whether these would improve the accuracy of the aqueous solubility models. Multiple linear regression employing an expectation maximization algorithm and a sparse prior (MLREM) method and a nonlinear Bayesian regularized artificial neural network with a Laplacian prior (BRANNLP) were used to derive optimal predictive models of aqueous solubility of a large and highly diverse data set of 4558 organic compounds over a normal ambient temperature range of 20–30 °C (293–303 K). A randomly selected test set and compounds from a solubility challenge were used to estimate the predictive ability of the models. The BRANNLP method showed the best statistical results with squared correlation coefficients of 0.90 and standard errors of 0.645–0.665 log(S) for training and test sets. Surprisingly, including descriptors that captured crystal lattice interactions did not significantly improve the quality of these aqueous solubility models.

Amphiphilic lyotropic liquid crystalline self-assembled nanomaterials have important applications in the delivery of therapeutic and imaging agents. However, little is known about the effect of the incorporated drug on the structure of nanoparticles. Predicting these properties is widely considered intractable. We present computational models for three drug delivery carriers, loaded with 10 drugs at six concentrations and two temperatures. These models predicted phase behavior for 11 new drugs. Subsequent synchrotron small-angle X-ray scattering experiments validated the predictions.

This paper proposes a method for monitoring the position of a vehicle on a lane. Cameras are mounted on the sides of vehicle and focus downwards on the road to capture images containing the lane lines and wheels/vehicle boundaries. The Hough transform (HT) is employed to detect the lane from the captured images. The correlation of sequential images and the constraints of lane lines and cameras are used to minimize the region of interest (RoI) in both image space and HT space, which increases the capture accuracy and decrease the computation complexity. The lane position monitoring system is assumed to be useful for unmanned vehicles, and can also provide warmings in normal vehicles to enhance driving safety. The experiments show the method is effective on various roads and driving situations.

The steering-wheel—steering-column assemblies fitted in automobiles must have a high energy absorption performance in order to minimize occupant chest injuries in the event of a collision. This paper proposes a novel built-in energy-absorbing (EA) component which causes the impact load transmitted to the occupant to vary in accordance with the crash severity and the occupant mass. A finite element (FE) model of the steering-column system is constructed on the basis of realistic product computer-aided design data, and a series of LS-DYNA simulations are performed to examine the dynamic responses of the steering wheel and steering column in body block impact tests performed using body blocks of different weights. The validity of the FE model is confirmed by comparing the numerical results for the torso force profile over the duration of the impact with the experimental results obtained in two standard body block tests. The validated model is then used to examine the energy absorption performance of the proposed EA device consisting of a hollow cylindrical tube patterned with an array of circular openings. The simulations focus specifically on the effects of the total hole-opening area, the cylinder thickness, and the cylinder material on the torso force profile over the duration of the impact. It is shown that, given an appropriate specification of the design parameters, the proposed EA device satisfies the peak load requirement specified in the FMVSS 203 standard and absorbs 163 J and 235 J of the impact kinetic energy for body block weights of 24 kgf and 34 kgf respectively.

We reviewed the clinical characteristics, required intervention and short- and long-term outcomes in obstructive sleep apnoea (OSA) patients requiring intensive care. A retrospective, single-centre, observational cohort study was undertaken in a multidisciplinary teaching medical and surgical intensive care unit. Adult patients with OSA (apnoea-hypopnoea index of 5 or higher) requiring intensive care from January 2000 to January 2005 were included. Thirty-seven OSA patients (age: 58±14 years, male:female 27:10) were admitted due to respiratory (n=12, 32%), cerebrovascular (n=8, 22%), cardiovascular (n=16, 43%) and infectious events (n=1, 2.7%). Comparing the clinical features, polysomnographic data and outcome among these groups, we found that OSA patients admitted due to respiratory events had significantly higher Acute Physiology and Chronic Health Evaluation II scores, lower arterial blood gas pH, higher PaCO2, a higher incidence of respiratory failure (92%) and required non-invasive ventilation after extubation (73%), and higher intensive care unit readmission rates than patients admitted due to cerebrovascular events and cardiovascular events (P <0.05). No difference was found in the in-hospital and long-term mortality rate.The most common reason for intensive care unit admission in critically ill OSA patients was a cardiovascular event, followed by respiratory and cerebrovascular events. The baseline polysomnographic data of the OSA patients were not correlated with their clinical features and outcomes in the intensive care unit. A more complicated clinical course and higher intensive care unit readmission rate were encountered in OSA patients admitted due to respiratory events. Further studies would be required to evaluate the efficacy of non-invasive ventilation for facilitation of extubation in OSA patients presenting with hypercapnic respiratory failure.

Polarized piezoreflectance PzR and photoreflectance PR are employed to study band alignment in Ga0.46In0.54NyP1–yGaAs heterostructures grown by gassource molecularbeam epitaxy. The features near the band edge of Ga0.46In0.54NyP1–yshow strong polarization dependence, indicating the existence of some degree of ordering of these samples. The PR spectra exhibit Franz–Keldysh Oscillations FKOs above the band edge of GaAs. The electric fields in the GaAs region are evaluated by analyzing the FKOs and found to decrease with increasing nitrogen content. The typeII band alignment at the Ga0.46In0.54NyP1–yGaAs interface is concluded for the alloys with nitrogen content ylarger than 0.5 based on the appearance of additional features below band edge of GaAs. These features are attributed to the spatially indirect typeII transitions in the vicinity of interface region between Ga0.46In0.54NyP1–yand GaAs. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim

Aims. The radiance and Doppler-shift distributions across the solar network provide observational constraints of two-dimensional modeling of transition-region emission and flows in coronal funnels. These distributions have not, however, been studied in detail and we attempt an investigation for a quiet Sun region.Methods. Two different methods, dispersion plots and average-profile studies, were applied to investigate these distributions for three EUV?lines. In the dispersion plots, we divided the entire quiet Sun region scanned by SUMER into a bright and a dark part according to an image of Fe?xii taken by EIT during the scanning; we plotted intensities and Doppler shifts in each bin as determined according to a filtered intensity of Si?ii. We also studied the difference in height variations of the magnetic field as extrapolated from the MDI magnetogram, in and outside network, in the two parts. For the average-profile study, we selected 74?individual cases and derived the average profiles of intensities and Doppler shifts across the network. Cases with large values of blue shift of Ne?viii were further studied. Results. The dispersion plots reveal that the intensities of Si?ii and C?iv increase from network boundary to network center in both the bright and dark parts. However, the intensity of Ne?viii shows different trends, namely increasing in the bright part and decreasing in the dark part. In both parts, the Doppler shift of C?iv increases steadily from internetwork to network center. The height variations in the magnetic field imply a more homogeneous magnetic structure at greater heights and clearly reflect the different magnetic structures in the two regions. The average-profile study reveals that the intensities of the three lines all decline from the network center to internetwork region. The binned intensities of Si?ii and Ne?viii have a good correlation. We also find that the large blue shift of Ne?viii does not coincide with large red shift of C?iv.Conclusions. Our results suggest that the network structure is still prominent at the layer where Ne?viii is formed in the quiet Sun, and that the magnetic structures expand more strongly in the dark part than in the bright part of this quiet Sun region. Our results might also hint for a scenario of magnetic reconnection between open funnels and side loops.

Aims. We study the height variations of the sizes of chromospheric and transition-region features in a small coronal hole and the adjacent quiet Sun, considering images of the intensity, Doppler shift, and non-thermal motion of ultraviolet emission lines as measured by SUMER (Solar Ultraviolet Measurements by Emitted Radiation), together with the magnetic field as obtained by extrapolation from photospheric magnetograms.Methods. In order to estimate the characteristic sizes of the different features present in the chromosphere and transition region, we have calculated the autocorrelation function for the images as well as the corresponding extrapolated magnetic field at different heights. The Half Width at Half Maximum (HWHM) of the autocorrelation function is considered to be the characteristic size of the feature shown in the corresponding image.Results. Our results indicate that, in both the coronal hole and quiet Sun, the HWHM of the intensity image is larger than that of the images of Doppler-shift and non-thermal width at any given altitude. The HWHM of the intensity image is smaller in the chromosphere than in the transition region, where the sizes of intensity features of lines at different temperatures are almost the same. But in the upper part of the transition region, the intensity size increases more strongly with temperature in the coronal hole than in the quiet Sun. We also studied the height variations of the HWHM of the magnetic field magnitude B and its component |Bz|, and found they are equal to each other at a certain height below 40?Mm in the coronal hole. The height variations of the HWHM of |Bz/B | seem to be consistent with the temperature variations of the intensity size.Conclusions. Our results suggest that coronal loops are much lower, and magnetic structures expand through the upper transition region and lower corona much more strongly with height in the coronal hole than in the quiet Sun.

Aims.The physical implication of large blue shift of Ne?viii in the quiet Sun region is investigated in this paper.Methods.We compare the significant Ne?viii blue shifts, which are visible as large blue patches on the Doppler-shift map of a middle-latitude quiet-Sun region observed by SUMER, with the coronal magnetic-field structures as reconstructed from a simultaneous photospheric magnetogram by means of a force-free-field extrapolation.Results.We show for the first time that coronal funnels also exist in the quiet Sun. The region studied contains several small funnels that originate from network lanes, expand with height and finally merge into a single wide open-field region. However, the large blue shifts of the Ne?viii line are not generally associated with funnels. A comparison between the projections of coronal loops onto the solar x-y-plane and the Ne?viii dopplergram indicates that there are some loops that reveal large Ne?viii blue shifts in both legs, and some loops with upflow in one and downflow in the other leg.Conclusions.Our results suggest that strong plasma outflow, which can be traced by large Ne?viii blue shift, is not necessarily associated with the solar wind originating in coronal funnels but appears to be a signature of mass supply to coronal loops. Under the assumption that the measured Doppler shift of the Ne?viii line represents the real outflow velocity of the neon ions being markers of the proton flow, we estimate the mass supply rate to coronal loops to be about 1034?s-1.

In this paper we will review our recent results from optical characterization studies of GaInNP. We will show that N incorporation in these alloys affects their structural and defect properties, as well as the electronic structure. The main structural changes include (i) increasing carrier localization due to strong compositional fluctuations, which is typical for all dilute nitrides, and (ii) N-induced long range ordering effects, specific for GaInNP. The observed degradation of radiative efficiency of the alloys upon increasing N content is attributed to formation of several defects acting as centres of efficient non-radiative recombination. One of the defects is identified as a complex involving a Ga interstitial atom. N incorporation is also found to change the band line up from the type I in the GaInP/GaAs structures to the type II in the GaInNP/GaAs heterojunctions with [N] > 0.5%. For the range of N compositions studied ([N] ≤ 2%), a conduction band offset at the GaInNP/GaAs interface is found to nearly linearly depend on [N] at –0.10 eV/%, whereas the valence band offset remains unaffected. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Densities, viscosities, refractive indices, and surface tensions for 12 flavor esters were measured from 288.15 K to 358.15 K at atmospheric pressure. The esters studied were ethyl acetoacetate, isoamyl acetate, ethyl isovalerate, methyl benzoate, ethyl caproate, ethyl benzoate, benzyl acetate, isoamyl butyrate, ethyl salicylate, benzyl propionate, ethyl phenylacetate, and ethyl caprylate. Densities were determined using a vibrating-tube density meter, and viscosities were measured with an automatic Ubbelohde capillary viscometer. Refractive indices were measured using a digital Abbe-type refractometer, and surface tensions were measured using the Wilhelmy-plate method. The experimental data were correlated by temperature-dependent equations.

Densities, viscosities, and refractive indices of the ternary system ethanol + 2-methylpropan-2-ol + 2,2,4-trimethylpentane at T = 298.15 K and the binary systems ethanol + 2-methylpropan-2-ol, ethanol + 2,2,4-trimethylpentane, and 2-methylpropan-2-ol + 2,2,4-trimethylpentane were measured at T = (298.15, 308.15, and 318.15) K and atmospheric pressure over the whole composition range. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling ball principle. Refractive indices were measured using a digital Abbe-type refractometer. Excess molar volumes (V^E), deviations in the viscosity (Δη) from the mole fraction average, and deviations in the refractive index (ΔnD) from the volume fraction average for the mixtures were derived from experimental data. The binary and ternary data of V^E, Δη, and ΔnD were correlated as a function of the mole fraction by using the Redlich−Kister and the Cibulka equations.

Immobilized pH gradients isoelectric focusing (IPG-IEF) is the first dimension typically used in two-dimensional gel electrophoresis (2-DE). It can also be used on its own in conjunction with tandem mass spectrometry (MS/MS) for the analysis of proteins. Here, we described a strategy combining isoelectric focusing in immobilized pH gradient strips, and mass spectrometry to create a new high-throughput and sensitive detection method. Protein mixture is separated by in-gel IEF, then the entire strip is cut into a set of gel sections. Proteins in each gel section are digested with trypsin, and the resulted peptides are subjected to reversed-phase high performance liquid chromatography followed by electrospray-linear ion-trap tandem mass analysis. Using this optimized strategy, we have identified 744 distinct human proteins from an IPG strip loaded only 300 μg of plasma proteins. When compared with other works in published literatures, this study offered a more convenient and sensitive method from gel to mass spectrometry for the separation and identification proteins of complex biological samples. Keywords: plasma • immobilized pH gradients • isoelectric focusing • proteomics • linear ion trap mass spectrometry

Densities, viscosities, and refractive indices of the ternary system diisopropyl ether + ethanol + methylcyclohexane at T = 298.15 K and the binary systems diisopropyl ether + ethanol, diisopropyl ether + methylcyclohexane, and ethanol + methylcyclohexane were measured at T = (288.15, 298.15, and 308.15) K and atmospheric pressure over the whole composition range. Densities were determined using a vibrating-tube density meter. Viscosities were measured with an automatic Ubbelholde capillary viscometer. Refractive indices were measured using a digital Abbe-type refractometer. Excess molar volumes V^E, deviations in the viscosity Δη, and deviations in the refractive index ΔnD for the mixtures were derived from experimental data. The binary data of V^E, Δη, and ΔnD were correlated as a function of the mole fraction by using the Redlich−Kister equation. For the ternary data, several polynomial equations have been tested to minimize the set of parameters for adequate correlation.

Densities and viscosities of the ternary mixture ethanol + 2-butanone + 2,2,4-trimethylpentane and the binary mixtures ethanol + 2-butanone, ethanol + 2,2,4-trimethylpentane, and 2-butanone + 2,2,4-trimethylpentane were measured at T = (298.15, 308.15, and 318.15) K and atmospheric pressure over the whole composition range. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic Ubbelohde capillary viscometer. Excess molar volumes V^E and deviations in viscosity Δη for the mixtures were derived from experimental data. The binary data were correlated with liquid composition by using the Redlich−Kister equation. For the ternary data, several polynomial equations have been tested to minimize the set of parameters for adequate correlation.

Nitrogen ions were implanted into silicon single crystal wafers followed by thermal annealing and anodization to form porous Si3N4 /Si composite. Using this porous Si3N4/Si composite films we have successfully fabricated a surface type humidity sensor. Experimental results show that its capacitance increases with the sensitivity of 33.5 pF/% RH in ambient humidity from 11.3% RH to 93.58% RH. The sensor has less hysteresis than ordinary porous Si sensor. The measured response time and hysteresis was 27 s and 7% RH respectively. The observed characteristics suggest the application of porous Si3N4/Si composite to future chemical sensors. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Isobaric vapor−liquid equilibria (VLE) data were measured at 101.3 kPa on four oxygenates (acetone, diisopropyl ether, ethanol, and methyl ethyl ketone) separately with hydrocarbon mixtures. Acetone, ethanol, and methyl ethyl ketone were mixed with a five-component hydrocarbon mixture and diisopropyl ether was mixed with a four-component hydrocarbon mixture. Calculations of nonideality of the vapor phase were made with the Soave−Redlich−Kwong equation of state. The vaporization equilibrium ratio of oxygenate in the hydrocarbon mixture was derived. Analysis of the experimental VLE data exhibits a minimum boiling temperature for the systems containing acetone, ethanol, and methyl ethyl ketone. The experimental data have been correlated with the mole fraction of oxygenate using the Redlich−Kister-type and Wisniak−Tamir equations.

Experimental results are reported for densities, ρ, and refractive indices, nD, of {(x)CH3(OCH2CH2)νOCH3 + (1 − x)C2H5OH} for ν = 1−4 at T = (288.15, 298.15, 308.15, and 318.15) K and atmospheric pressure over the entire mole fraction range. Densities were measured with a vibrating-tube densimeter, and excess volumes molar volumes, V^E, for the mixtures were derived. Refractive indices were measured using a digital refractometer, and deviations as a function of mole fraction, ΔnD, were calculated from the experimental data. The excess molar volumes are negative in every case and become more negative as the ν of the glycol increases. The deviations in refractive indices are generally positive and increase as the ν of the glycol increases. Excess molar volumes increase as the temperature increases, while deviations in refractive indices decrease as the temperature increases. The temperature has no significant effect on V^E of the glycols with ν = 3 and 4 in ethanol. Values of excess volumes and deviations in refractive indices as a function of composition were fitted to the Redlich−Kister equation.

Densities, viscosities, and refractive indexes were measured for the binary mixtures formed by methanol, ethanol, propan-1-ol, and butan-1-ol with 1-chlorobutane at T = (288.15, 298.15, and 308.15) K and atmospheric pressure over the whole concentration range. Excess molar volumes (V^E) were determined from the densities of pure liquids and mixtures measured with a vibrating-tube densimeter. Excess molar volumes, which increase as the temperature increases, are positive except for mixtures in the high mole fraction region of propan-1-ol or butan-1-ol. Viscosities were measured with an automatic Ubbelohde capillary viscometer. Refractive indexes were measured using a digital refractometer. Deviations in viscosity (Δη) and deviations in refractive index (ΔnD) as a function of mole fraction for the mixtures were derived from the experimental data. The computed results of V^E, Δη, and ΔnD were fitted to the Redlich−Kister equation. Furthermore, McAllister's three-body interaction model is used to correlate the binary kinematic viscosities.

Three novel Pt(II) complexes [PtL1‘Cl] I (L1‘ = glycine-N‘-8-quinolylamide), [PtL2‘Cl] II (L2‘ = l-alanine-N‘-8-quinolylamide), and [PtL3Cl] III [L3 = N-(tert-butoxycarbonyl)-l-methionine-N‘-8-quinolylamide] have been synthesized and characterized. The crystal structure of complexes II and III showed that the ligands are three-coordinated with only one Cl^- as the leaving group. Complex II crystallized in the monoclinic system with space group P2(1), a = 9.502(2) Å, b = 4.724(1) Å, c = 14.800(3) Å, while complex III crystallized in the orthorhombic system with space group P2(1)2(1)2(1), a = 5.441(1) Å, b = 12.978(3) Å, c = 29.438(6) Å. These complexes have been tested against a wide range of tumor cell lines including BEL-7402, HCT-116, SPC-A4, MOLT-4, P388, HL-60, A-549, SGC-7901, MKN-28, and HO-8910. Complex III is highly cytotoxic against the HCT-116 (IC50 = 0.38 μM), SPC-A4 (IC50 = 0.43 μM), BEL-7402 (IC50 = 0.43 μM), and MOLT-4 (IC50 = 0.61 μM) cell lines. The cell line most sensitive to III is human liver carcinoma cell line BEL-7402, which has a response rate of 75.1% at 6.6 × 10^-7 M, nearly 6 times higher than that of cisplatin.

This paper describes and characterizes a novel microfabricated neuronal culture device. This device combines microfabrication, microfluidic, and surface micropatterning techniques to create a multicompartment neuronal culturing device that can be used in a number of neuroscience research applications. The device is fabricated in poly(dimethylsiloxane), PDMS, using soft lithography techniques. The PDMS device is placed on a tissue culture dish (polystyrene) or glass substrate, forming two compartments with volumes of less than 2 μL each. These two compartments are separated by a physical barrier in which a number of micron-size grooves are embedded to allow growth of neurites across the compartments while maintaining fluidic isolation. Cells are plated into the somal (cell body) compartment, and after 3−4 days, neurites extend into the neuritic compartment via the grooves. Viability of the neurons in the devices is between 50 and 70% after 7 days in culture; this is slightly lower than but comparable to values for a control grown on tissue culture dishes. Healthy neuron morphology is evident in both the devices and controls. We demonstrate the ability to use hydrostatic pressure to isolate insults to one compartment and, thus, expose localized areas of neurons to insults applied in soluble form. Due to the high resistance of the microgrooves for fluid transport, insults are contained in the neuritic compartment without appreciable leakage into the somal compartment for over 15 h. Finally, we demonstrate the use of polylysine patterning in combination with the microfabricated device to facilitate identification and visualization of neurons. The ability to direct sites of neuronal attachment and orientation of neurite outgrowth by micropatterning techniques, combined with fluidically isolated compartments within the culture area, offers significant advantages over standard open culture methods and other conventional methods for manipulating distinct neuronal microenvironments.

A Raman spectroscopic study was performed on a Pb(Zn1/3Nb2/3)0.915Ti0.085O3 crystal to study the ordered nano-regions. The variation of the Raman spectra with temperature in the range from −200 to 1000°C clearly exhibited a rhombohedral–tetragonal transition at about 75°C followed by a tetragonal–cubic transition at about 175°C. The polarization behavior of the 777 cm⁻¹ octahedral mode suggested the existence of Fm3m nano-ordered regions in Pm3m cubic symmetry. Thermal switching of nano-region polarization was observed above 388°C as the thermal energy became greater than the activation energy of nano-clusters and resulted in a decrease in the polarized intensity of the 777 cm⁻¹ mode. However, both the 51 and 777 cm⁻¹ modes were observed up to 1000°C. Copyright © 2003 John Wiley & Sons, Ltd.

Densities and viscosities were measured for the systems of four oxygenates (acetone, diisopropyl ether, ethanol, and methyl ethyl ketone) separately with a five-component hydrocarbon mixture at three temperatures (288.15, 298.15, and 308.15) K and atmospheric pressure. The five-component hydrocarbon mixture contains 25 mol % hexane, 10 mol % heptane, 35 mol % 2,2,4-trimethylpentane, 20 mol % toluene, and 10 mol % p-xylene. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic Ubbelohde capillary viscometer. Excess molar volumes V^E and deviations in viscosity Δη for the mixtures were derived from experimental data, and the computed results were fitted to a Redlich−Kister-type equation.