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Sustained, quantitative observations of nearshore waves and sand levels are essential for testing beach evolution models, but comprehensive datasets are relatively rare. We document beach profiles and concurrent waves monitored at three southern California beaches during 2001–2016. The beaches include offshore reefs, lagoon mouths, hard substrates, and cobble and sandy (medium-grained) sediments. The data span two energetic El Niño winters and four beach nourishments. Quarterly surveys of 165 total cross-shore transects (all sites) at 100 m alongshore spacing were made from the backbeach to 8 m depth. Monthly surveys of the subaerial beach were obtained at alongshore-oriented transects. The resulting dataset consists of (1) raw sand elevation data, (2) gridded elevations, (3) interpolated elevation maps with error estimates, (4) beach widths, subaerial and total sand volumes, (5) locations of hard substrate and beach nourishments, (6) water levels from a NOAA tide gauge (7) wave conditions from a buoy-driven regional wave model, and (8) time periods and reaches with alongshore uniform bathymetry, suitable for testing 1-dimensional beach profile change models., Design Type(s)database creation objective • modeling and simulation objectiveMeasurement Type(s)bathymetry and wavesTechnology Type(s)OceanographyFactor Type(s)geographic locationSample Characteristic(s)San Diego • ocean Machine-accessible metadata file describing the reported data (ISA-Tab format)

Background Fat grafting is a common procedure in plastic surgery. A major limitation is unpredictable graft retention, in part caused by inadequate oxygen delivery during the early posttransfer period. Methods The authors present a bioengineered approach to the design of a fat graft based on mathematical theory, which can estimate the limitations of oxygen delivery. To simplify the problem, four variables were defined: (1) recipient-site oxygen partial pressure; (2) adipose tissue oxygen permeability; (3) adipose tissue oxygen consumption rate; and (4) fat graft size. Recipient-site oxygen partial pressure and adipose tissue oxygen permeability were estimated from literature, whereas adipose tissue oxygen consumption rate was measured using stirred microchamber technology. Calculations were performed in both spherical and planar geometry to calculate the maximum allowable fat graft size from an oxygen delivery standpoint. Results As expected, planar geometry is less favorable for oxygenation but represents a realistic configuration for a fat graft. Maximum allowable fat graft thickness is only approximately 1 to 2 mm at external oxygen partial pressures of 10 to 40 mm Hg; any thicker and an anoxic or necrotic core likely develops. Given a reasonably large surface area and assuming several planes of injection, the maximum allowable fat graft volume is tens of milliliters. Conclusions A systematic bioengineered approach may help better design a fat graft. Applying principles of mass transfer theory can predict whether a fat graft has a favorable chance of surviving from an oxygen delivery standpoint and can direct the development of strategies for improved fat graft oxygenation.

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Metal-organic frameworks (MOFs) can theoretically yield a nearly infinite number of nanoporous materials, which represents a combinatorial design challenge that demands computational tools rather than experimental trial-and-error. Here we report Quantitative Structure–Property Relationship (QSPR) models to identify high-performing MOFs for methane purification solely using geometrical features. The CO2working capacity and CO2/CH4selectivity of ca. 320,000 hypothetical MOF structures was computed at conditions relevant to natural gas purification using grand canonical Monte-Carlo (GCMC) simulations. Using 32,500 MOF structures we calibrated binary decision tree (DT) and support vector machine (SVM) models that can accurately identify high-performing MOFs based on their pore size, void fraction and surface area. DT models yielded guidelines of pore size, void fraction and surface area for designing high-performing materials. The SVM machine learning classifiers could be used to quickly pre-screen MOFs, such that compute intensive GCMC simulations are not performed on all structures. The SVM classifiers were tested on ca. 290,000 MOFs that were not part of the training set and could correctly identify up to 90 % of high-performing MOFs while only flagging a fraction of the MOFs for more rigorous screening. QSPR models constitute efficient computational tools for the virtual screening of large structural libraries and provide rational design rules for the discovery of sorbents for methane purification.

A new energy-based multifunctional efficiency (MFE) metric is developed using micromechanics solutions for structural supercapacitors consisting of composite electrodes that can store electrical energy and sustain mechanical loads. MFE metrics quantify the volume and/or mass savings when structural and functional materials are replaced by multifunctional materials and evaluate the trade-off between different functionalities. Commonly used multifunctionality metrics for structural supercapacitors are based on the rule of mixtures for both mechanical and electrical performance. These metrics provide an adequate approximation for some electrode geometries and loading conditions, such as longitudinal direction for aligned fibers in multifunctional composite electrodes and in-plane directions for laminate composite electrodes. However, if supercapacitors with complex microstructure or multiple electrode materials encompass more complex geometries or orientations of the structural and functional phases, a more comprehensive method is required to accurately capture the MFE. The MFE proposed herein can account for complex geometries and different mechanical loading conditions by using micromechanics methods. The shapes considered here include layered composite supercapacitors, fibrous films and any shape that can be derived from an ellipsoid. When calculated utilizing the proposed metric, the MFE varies by orders of magnitude due to the difference in shapes and applied mechanical fields to the supercapacitors, while existing metrics provide a constant upper bound. The influence of Young’s modulus difference between multifunctional electrodes and solid electrolytes is also discussed.

Bdellovibrio bacteriovorus is a predator of Gram-negative bacteria and there is limited research on its utility for decontamination of post-harvest produce. The objective of this research was to determine reduction of E. coli O157:H7 and Salmonella on lettuce and carrot by B. bacteriovorus 109 (Bb109) and evaluate its survival and E. coli in buffer and on lettuce following gamma radiation exposure. Bb109 was cultured on ML35, filtered, and predator cells were suspended in buffer. Produce and buffer were co-inoculated with E. coli and Salmonella, separately; and Bb109 applied. In a separate experiment, Bb109 were inoculated on lettuce and suspended in buffer, then irradiated at 0.25–1.0 kGy treatments. E. coli and Salmonella in buffer were reduced by Bb109 0.4–3.9 and 0.9–2.6 logs, respectively. The predation of E. coli by Bb109 on carrot and lettuce resulted in 0.3–1.8 log reductions, and for Salmonella on the same produce, they were 0.9 and 1.2 logs, respectively. In radiation sensitivity assays, Bb109 populations in buffer and lettuce were inactivated by 3–5 logs (0.5 kGy). Bdellovibrio could aid the mortality of pathogenic bacteria during post-harvest treatment or in hurdle interventions of post-harvest produce. No previous data on Bdellovibrio exposure to radiation is available.

Metal organic frameworks (MOFs) are a diverse class of materials built from organic and inorganic building units that can self assemble to form nanoporous frameworks. The hallmark feature of MOFs is the potential to tune the materials for any given application, which arises from the seemingly endless number of combinations of building units one can construct the materials from. To overcome this combinatorial design challenge we have developed a number of in silico screening tools and applied it to the development of new materials for gas separation processes such as post-combustion CO2 capture. First we have constructed a database of millions hypothetical materials using a novel structure spawning algorithm in which MOF structures can be generated from any topological periodic net (~1800 are experimentally known). Using molecular simulation techniques, we have screened the hypothetical materials for their gas adsorption properties, which provides the locations of the guest-host binding sites in each material. From the best performing materials, a similarity analysis was performed on over 100,000 binding sites to determine if the best performing materials share any common features in their binding sites. For the application of post-combustion CO2 capture, we found that two aromatic rings separated by 7.2 Ang provide an ideal, hydrophobic binding pocket that selectively adsorbs CO2. Our experimental collaborators were then able to synthesize 2 new MOFs with the targeted binding pockets and experimentally confirm that CO2 binds in them as predicted. To date these MOFs are amongst the best materials for selective CO2 capture under realistic humid combustion gas streams. Time permitting, we will also present how we have used deep learning models of nanoporous materials to rapidly predict the low-pressure adsorption properties of MOFs. Under these conditions, the chemistry of the pores is important and the geometric features such as the pore size, are not good predictors of the performance of the materials. Using a distance-between-features descriptor that accounts for the local chemistry of the materials, we have been able to develop accurate models that can predict the adsorption properties of nanoporous materials. Models were trained and tested on large, diverse databases of over 330,000 MOFs giving correlation R2 values on the test sets of >0.95, while geometric features provide R2 values of 0.71.

The finite element method is used to simulate frictional sliding contact between a rigid cylinder and a shape memory alloy (SMA) half-space. A set of parametric studies are conducted to investigate the effects of typical SMA phenomenological behaviors such as the influence of temperature on the constitutive behavior, large recoverable strains and the difference between the elastic moduli of the SMA austenite and martensite phases on the sliding response. The simulations show that significant residual stresses are present far away from the contact region for sliding at temperatures below the austenitic finish temperature. The simulations also reveal that the maximum von Mises stress in the half-space during sliding contact decreases for higher values of recoverable transformation strains and for a SMA with a more compliant stress-induced martensite phase compared to the austenite phase. In contrasting the effects of the energy dissipation mechanisms of a pseudoelastic and a conventional elastic-plastic half-spaces on the sliding response, it is shown that the former continues to dissipate energy after repeated sliding cycles while the latter ceases to dissipate energy upon reaching an elastic shakedown state.

Charge equilibration (Qeq) methods can estimate the electrostatic potential of molecules and periodic frameworks by assigning point charges to each atom, using only a small fraction of the resources needed to compute density functional (DFT)-derived charges. This makes possible, for example, the computational screening of thousands of microporous structures to assess their performance for the adsorption of polar molecules. Recently, different variants of the original Qeq scheme were proposed to improve the quality of the computed point charges. One focus of this research was to improve the gas adsorption predictions in metal-organic frameworks (MOFs), for which many different structures are available. In this work, we review the evolution of the method from the original Qeq scheme, understanding the role of the different modifications on the final output. We evaluated the result of combining different protocols and set of parameters, by comparing the Qeq charges with high quality DFT-derived DDEC charges for 2338 MOF structures. We focused on the systematic errors that are attributable to specific atom types to quantify the final precision that one can expect from Qeq methods in the context of gas adsorption where the electrostatic potential plays a significant role, namely, CO2 and H2S adsorption. In conclusion, both the type of algorithm and the input parameters have a large impact on the resulting charges, and we draw some guidelines to help the user to choose the proper combination of the two for obtaining a meaningful set of charges. We show that, considering this set of MOFs, the accuracy of the original Qeq scheme is often still comparable with the most recent variants, even if it clearly fails in the presence of certain atom types, such as alkali metals., European Union (EU); H2020; European Research Council (ERC)-2017-Starting Grant; Swedish Science Council (VR); Swiss National Supercomputing Centre (CSCS); European Research Council (ERC) European Union’s Horizon 2020 research and innovation programme; NCCR Marvel; INSPIRE Potentials Master's Fellowship; COSMOS

Many multifunctional composite structures incorporate porosity at various length scales to increase the available surface area of a functional component. One material system of particular interest is activated or porous carbon fibers and nanofibers that can serve as structural reinforcement as well as providing active surface for added functionality. A key question in the design and manufacture of these fibers is to what degree the induced pore affects the mechanical properties by inducing discontinuities in the material. To address this problem, mechanics of porous carbon nanofibers (CNFs) was studied for the first time as a function of their porous structure. Hollow CNF with porous shell was prepared by coaxial electrospinning a polyacrylonitrile/poly(methyl methacrylate) (PMMA) blend shell with a PMMA core. PMMA was removed by thermal decomposition during pyrolysis to form pores. Solid-shell CNF was prepared as a control with no PMMA in the shell. Results show that the modulus and strength of the porous-shell CNF with a porosity of 19.2 ± 1.3% were 65.0 ± 6.2 and 1.28 ± 0.14 GPa respectively, 13.9 ± 2.1% and 35.5 ± 4.9% lower than those of the solid-shell CNF. Finite-element analysis models were developed to decouple the effect of stress concentration and reduced load-bearing area in porous CNFs on their mechanical properties. The model predictions were in general agreement with the experimental results and were used to identify the most critical parameters that can affect load bearing in porous nanofibers. Considering the comparison of the experimental and modeling results, the intrinsic material strength (of the solid parts) does not seem to be affected by inducing pores; thus, fiber and pore geometries might be developed where the load paths are designed for even less of a strength loss.

In this work, we report the synthesis of SION-8, a novel metal–organic framework (MOF) based on Ca(II) and a tetracarboxylate ligand TBAPy4– endowed with two chemically distinct types of pores characterized by their hydrophobic and hydrophilic properties. By altering the activation conditions, we gained access to two bulk materials: the fully activated SION-8F and the partially activated SION-8P with exclusively the hydrophobic pores activated. SION-8P shows high affinity for both CO2 (Qst = 28.4 kJ/mol) and CH4 (Qst = 21.4 kJ/mol), while upon full activation, the difference in affinity for CO2 (Qst = 23.4 kJ/mol) and CH4 (Qst = 16.0 kJ/mol) is more pronounced. The intrinsic flexibility of both materials results in complex adsorption behavior and greater adsorption of gas molecules than if the materials were rigid. Their CO2/CH4 separation performance was tested in fixed-bed breakthrough experiments using binary gas mixtures of different compositions and rationalized in terms of molecular interactions. SION-8F showed a 40–160% increase (depending on the temperature and the gas mixture composition probed) of the CO2/CH4 dynamic breakthrough selectivity compared to SION-8P, demonstrating the possibility to rationally tune the separation performance of a single MOF by manipulating the stepwise activation made possible by the MOF’s biporous nature.

This study uses the finite element method to analyze the sliding contact behavior between a rigid cylinder and a shape memory alloy (SMA) semi-infinite half-space. An experimentally validated constitutive model is used to capture the pseudoelastic effect exhibited by these alloys. Parametric studies involving the maximum recoverable transformation strain and the transformation temperatures are performed to analyze the effects that these parameters have on the stress fields during indentation and sliding contact. It is shown that, depending on the amount of recoverable transformation strain possessed by the alloy, a reduction of almost 40 % of the maximum stress in the pseudoelastic half-space is achieved when compared to the maximum stress in a purely elastic half-space. The studies also reveal that the sliding response is strongly temperature dependent, with significant residual stress present in the half-space at temperatures below the austenitic finish temperature.

Limiting the increase of CO

Metal–organic frameworks (MOFs) have emerged as versatile materials for applications ranging from gas separation and storage, catalysis, and sensing. The attractive feature of MOFs is that, by changing the ligand and/or metal, they can be chemically tuned to perform optimally for a given application. In most, if not all, of these applications one also needs a material that has a sufficient mechanical stability, but our understanding of how changes in the chemical structure influence mechanical stability is limited. In this work, we rationalize how the mechanical properties of MOFs are related to framework bonding topology and ligand structure. We illustrate that the functional groups on the organic ligands can either enhance the mechanical stability through formation of a secondary network of nonbonded interactions or soften the material by destabilizing the bonded network of a MOF. In addition, we show that synergistic effect of the bonding network of the material and the secondary network is required to achieve optimal mechanical stability of a MOF. The developed molecular insights in this work can be used for systematic improvement of the mechanical stability of the materials by careful selection of the functional groups., The mechanical stability of metal−organic frameworks can be significantly enhanced and/or tuned by rational decoration of ligands with functional groups via secondary networks.

High strength hollow carbon fibers with both porous and solid shell were fabricated by a combination of coaxial electrospinning and emulsion electrospinning. In the coaxial electrospinning, a Polyacrylonitrile (PAN)/ Poly(methyl methacrylate) (PMMA)/Dimethylformamide (DMF) emulsion was used to form the porous shell and a PAN/DMF solution was used to form the solid shell. Fiber surface and cross-section morphology was studied by scanning electron microscope (SEM). Mechanical property of the hollow fibers was characterized by single fiber tensile test using microelectromechanical system devices (MEMS). The effect of pores on mechanical performance of the hollow fibers was studied. Hollow carbon fibers with porous and solid shell both showed a brittle fracture behavior. The modulus and strength of the hollow carbon fibers with solid shell was ∼ 76.1 GPa and 2.04 GPa, respectively. For the hollow carbon fibers with porous shell, the porosity led to ∼ 35 % reduction in strength. The porous fibers with the mediocre strength measured here open new horizons for combining structural functionality with energy storage, in so-called structural batteries.

Here we present a method for constructing hypothetical crystalline nanoporous materials, such as metal–organic frameworks (MOFs), using a graph theoretical approach. The method takes as input the discrete secondary (or structural) building units (SBUs) with defined connection points, and a desired 3-dimensional net topology in the form of a labelled quotient graph. The hypothetical materials are constructed based on the principle that using a labelled quotient graph obtained, for example from the reticular chemistry structure resource (RCSR), one can construct a net embedding in 3-D Euclidean space with an infinite number of different representations. Thus, crystalline structures can be realized by manipulating a net's embedding such that vertices of the net match the geometries of the desired SBUs. To demonstrate the methodology, 46 different network topologies (i.e.tbo, pcu), are used to build MOFs from the same pair of 4-coordinate and 3-coordinate SBUs. We further show that the method can be used to generate hypothetical MOFs where the most common realization of a net, called the barycentric representation, will not produce a viable structure. When combined with a robust force field based geometry optimizer, the method can be used to generate large and structurally diverse hypothetical databases for virtual screening purposes.

International audience; In this work, we report the synthesis of SION-8, a novel metal-organic framework (MOF) based on Ca(II) and a tetracarboxylate ligand TBAPy(4-) endowed with two chemically distinct types of pores characterized by their hydrophobic and hydrophilic properties. By altering the activation conditions, we gained access to two bulk materials: the fully activated SION-8F and the partially activated SION-8P with exclusively the hydrophobic pores activated. SION-8P shows high affinity for both CO2 (Q(st) = 28.4 kJ/mol) and CH4 (Q(st) = 21.4 kJ/mol), while upon full activation, the difference in affinity for CO2 (Q(st) = 23.4 kJ/mol) and CH4 (Q(st) = 16.0 kJ/mol) is more pronounced. The intrinsic flexibility of both materials results in complex adsorption behavior and greater adsorption of gas molecules than if the materials were rigid. Their CO2/CH4 separation performance was tested in fixed-bed breakthrough experiments using binary gas mixtures of different compositions and rationalized in terms of molecular interactions. SION-8F showed a 40-160% increase (depending on the temperature and the gas mixture composition probed) of the CO2/CH4 dynamic breakthrough selectivity compared to SION-8P, demonstrating the possibility to rationally tune the separation performance of a single MOF by manipulating the stepwise activation made possible by the MOF's biporous nature.

Structural energy and power systems offer both mechanical and electrochemical performance in a single multifunctional platform. These are of growing interest because they potentially offer reduction in mass and/or volume for aircraft, satellites, and ground transportation. To this end, flexible graphene-based supercapacitors have attracted much attention due to their extraordinary mechanical and electrical properties, yet they suffer from poor strength. This problem may be exacerbated with the inclusion of functional guest materials, often yielding strengths of15 MPa. Here, we show that graphene paper supercapacitor electrodes containing aramid nanofibers as guest materials exhibit extraordinarily high tensile strength (100.6 MPa) and excellent electrochemical stability. This is achieved by extensive hydrogen bonding and π-π interactions between the graphene sheets and aramid nanofibers. The trade-off between capacitance and mechanical properties is evaluated as a function of aramid nanofiber loading, where it is shown that these electrodes exhibit multifunctionality superior to that of other graphene-based supercapacitors, nearly rivaling those of graphene-based pseudocapacitors. We anticipate these composite electrodes to be a starting point for structural energy and power systems that harness the mechanical properties of aramid nanofibers.

Control of foodborne pathogens on post-harvest produce may be improved by combined treatments. Hurdle applications may enhance the lethal effects of non-thermal interventions on pathogenic bacteria. We evaluated the effects of gamma radiation (0.5 kGy), nisin-based sanitizer (100%), and competitive biocontrol microbes (non-pathogenic Pseudomonas fluorescens) on the survival of Listeria monocytogenes on post-harvest tomato and carrot. Produce storage temperatures (5 and 20 °C) and days (0 and 7), with single, two or three treatment combinations of radiation (R), sanitizer (S) and biocontrol (B) were investigated for pathogen survival. Significant differences (P radiation > biocontrol. Inactivation of Listeria on post-harvest produce may be improved by treatment combinations as hurdle applications could enhance the safety of post-harvest carrot and tomato.

In this work, we have developed quantitative structure–property relationship (QSPR) models using advanced machine learning algorithms that can rapidly and accurately recognize high-performing metal organic framework (MOF) materials for CO2 capture. More specifically, QSPR classifiers have been developed that can, in a fraction of a section, identify candidate MOFs with enhanced CO2 adsorption capacity (>1 mmol/g at 0.15 bar and >4 mmol/g at 1 bar). The models were tested on a large set of 292 050 MOFs that were not part of the training set. The QSPR classifier could recover 945 of the top 1000 MOFs in the test set while flagging only 10% of the whole library for compute intensive screening. Thus, using the machine learning classifiers as part of a high-throughput screening protocol would result in an order of magnitude reduction in compute time and allow intractably large structure libraries and search spaces to be screened.

We describe a combined ultrasonic instrument for continuous gas flow measurement and simultaneous real-time binary gas mixture analysis. In the instrument, sound bursts are transmitted in opposite directions, which may be aligned with the gas flow path or at an angle to it, the latter configuration being the best adapted to high flow rates. The combined flow measurement and mixture analysis algorithm exploits the phenomenon whereby the sound velocity in a binary gas mixture at known temperature and pressure is a unique function of the molar concentration of the two components. The instrument is central to a possible upgrade to the present ATLAS silicon tracker cooling system in which octafluoropropane (C F ) evaporative cooling fluid would be replaced by a blend containing up to 25% hexafluoroethane (C 2 F 6 ). The instrument has been developed in two geometries following computational fluid dynamics studies of various mechanical layouts. An instrument with 45 crossing angle has been installed for commissioning in the ATLAS silicon tracker cooling system. It can be used in gas flows up to 20 000 l.min -1 and has demonstrated a flow resolution of 2.3% of full scale for linear flow velocities up to 10 m.s in preliminary studies with air. Other instruments are currently used to detect low levels of C 2 F 8 vapor leaking into the N 2 environmental gas surrounding the ATLAS silicon tracker. A long-duration continuous study of more than a year has demonstrated a sensitivity to mixture variation of better than 5.10 -5 .

We describe an ultrasonic instrument for continuous real-time analysis of the fractional mixture of a binary gas system. The instrument is particularly well suited to measurement of leaks of a high molecular weight gas into a system that is nominally composed of a single gas. Sensitivity < 5 × 10−5 is demonstrated to leaks of octaflouropropane (C3F8) coolant into nitrogen during a long duration (18 month) continuous study. The sensitivity of the described measurement system is shown to depend on the difference in molecular masses of the two gases in the mixture. The impact of temperature and pressure variances on the accuracy of the measurement is analysed. Practical considerations for the implementation and deployment of long term, in situ ultrasonic leak detection systems are also described. Although development of the described systems was motivated by the requirements of an evaporative fluorocarbon cooling system, the instrument is applicable to the detection of leaks of many other gases and to processes requiring continuous knowledge of particular binary gas mixture fractions.

Structural energy storage is a field associated with the combination of important functions such as structural reliability, energy storage, and energy delivery. The combination of said functions ensures savings in the overall volume and mass of the system. Reduced graphene oxide (rGO) and aramid nanofibers (ANF) composite film electrodes were developed for the purpose of structural energy storage. Graphene is studied due to its remarkable mechanical properties, electrical conductivity and electrochemical surface area. Furthermore, Kevlar® aramid nanofibers enhance the structural properties of the composite due to their excellent mechanical properties. However, external strains are expected on the composite film due to its structural function, and the response of the electrical properties to external strain needs to be evaluated. In this work, the change in electrical resistance was measured under bending-induced strain, using a home-built instrument that allows for accurate strain measurements using image analysis. We show that the resistance of the film decreases under bending via a mechanism we called “mechanical annealing.” This mechanism may be the effect of improved stacking of rGO sheets. The degree of mechanical annealing was also correlated to the amount of bending strain, as well as the amount of ANF loading. Our results demonstrate an improvement, rather than deterioration of the electrical resistance of rGO/ANF composite films under strain, making them suitable for structural energy storage applications.

The charge equilibration (QEq) method has been parametrized to reproduce the ab-initio-derived electrostatic potential in a large and diverse training set of 543 metal organic frameworks (MOFs) containing the most popular Zn, Cu, and V structural building units (SBUs), 52 different organic carboxylate- and nitrogen-capped SBUs, and the 17 functional groups. The MOF electrostatic-potential-optimized charge scheme, or MEPO-QEq, was validated by evaluating the CO2 uptake and heats of adsorption in the 543 member training set and a nonoverlapping 693 member validation set. Compared with the results obtained from ab-initio-derived charges, the MEPO-QEq charges give Pearson (linear) and Spearman (rank-order) correlation coefficients of >0.97 for these two sets. MEPO-QEq enables near-ab-initio quality nonbonded electrostatic interactions to be evaluated using the fast QEq method for fast and accurate virtual high-throughput screening of gas-adsorption properties in MOFs.

We evaluated knowledge of gynecologic cancer screening recommendations, screening behaviors, and communication with providers among women with Lynch syndrome (LS). Women aged ≥25 years who were at risk for LS-associated cancers completed a semi-structured interview and a questionnaire. Of 74 participants (mean age 40 years), 61% knew the appropriate age to begin screening, 75-80% correctly identified the recommended screening frequency, and 84% reported no previous screening endometrial biopsy. Women initiated discussions with their providers about their LS cancer risks, but many used nonspecific terms or relied on family history. Most were not offered high-risk screening options. While many women were aware of risk-appropriate LS screening guidelines, adherence was suboptimal. Improving communication between women and their providers regarding LS-related gynecologic cancer risk and screening options may help improve adherence.

PurposeCurrent research remains unclear on what factors contribute to cross‐functional team (CFT) success. Thus, the primary purpose of this investigation is to examine internal factors of the team (namely internal team environment, shared leadership, and cohesion) and the influence of each factor on CFT effectiveness.Design/methodology/approachStructural equation modeling is used to empirically examine the data collected from an undergraduate student sample. Teams worked competitively on a complex task requiring functional area expertise.FindingsResults from the study indicate internal team environment influences effectiveness through shared leadership and cohesion as found in other forms of teams. However, unique to CFTs, internal team environment is not directly related to effectiveness, and shared leadership does not directly influence cohesion. The findings suggest that in CFTs, internal team environment indirectly influences effectiveness.Research limitations/implicationsThe findings of this study can be used to expand current models of CFT effectiveness. Additionally, by examining the internal dynamics of the team (e.g. internal team environment) researchers will be better able to account for the previous vast differences found in CFT outcomes.Practical implicationsManagers interested in influencing team effectiveness are encouraged to focus on the internal dynamics of CFTs. To indirectly influence team effectiveness managers should insure teams establish a clear purpose and that members support one another and feel comfortable making contributions to the team.Originality/valueThis investigation offers understanding of how CFTs can be structured to influence effectiveness and provides insight into previously inconsistent findings. Both researchers and managers will benefit from an enhanced understanding of how internal factors uniquely influence CFT effectiveness.

© 2016 American Chemical Society. In this work, MOF bulk properties are evaluated and compared using several force fields on several well-studied MOFs, including IRMOF-1 (MOF-5), IRMOF-10, HKUST-1, and UiO-66. It is found that, surprisingly, UFF and DREIDING provide good values for the bulk modulus and linear thermal expansion coefficients for these materials, excluding those that they are not parametrized for. Force fields developed specifically for MOFs including UFF4MOF, BTW-FF, and the DWES force field are also found to provide accurate values for these materials’ properties. While we find that each force field offers a moderately good picture of these properties, noticeable deviations can be observed when looking at properties sensitive to framework vibrational modes. This observation is more pronounced upon the introduction of framework charges.

© 2017 American Chemical Society. For applications of metal-organic frameworks (MOFs) such as gas storage and separation, flexibility is often seen as a parameter that can tune material performance. In this work we aim to determine the optimal flexibility for the shape selective separation of similarly sized molecules (e.g., Xe/Kr mixtures). To obtain systematic insight into how the flexibility impacts this type of separation, we develop a simple analytical model that predicts a material’s Henry regime adsorption and selectivity as a function of flexibility. We elucidate the complex dependence of selectivity on a framework’s intrinsic flexibility whereby performance is either improved or reduced with increasing flexibility, depending on the material’s pore size characteristics. However, the selectivity of a material with the pore size and chemistry that already maximizes selectivity in the rigid approximation is continuously diminished with increasing flexibility, demonstrating that the globally optimal separation exists within an entirely rigid pore. Molecular simulations show that our simple model predicts performance trends that are observed when screening the adsorption behavior of flexible MOFs. These flexible simulations provide better agreement with experimental adsorption data in a high-performance material that is not captured when modeling this framework as rigid, an approximation typically made in high-throughput screening studies. We conclude that, for shape selective adsorption applications, the globally optimal material will have the optimal pore size/chemistry and minimal intrinsic flexibility even though other nonoptimal materials’ selectivity can actually be improved by flexibility. Equally important, we find that flexible simulations can be critical for correctly modeling adsorption in these types of systems.

Understanding how crystalline materials are assembled is important for the rational design of metal–organic frameworks (MOFs), through streamlining their synthesis and controlling their properties for targeted applications. Herein, we report for the first time the construction of two 3-dimensional Tb(III) based MOFs; a metastable MOF acting as an intermediate phase, that partially dissolves and transforms into a chemically and thermodynamically stable MOF. This chemical transformation occurs solely in a N,N-dimethylformamide/water solvent mixture, and is triggered when additional energy is provided to the reaction. In situ studies reveal the partial dissolution of the metastable phase after which the MOF components are reassembled into the thermodynamically stable phase. The marked difference in thermal and chemical stability between the kinetically and thermodynamically controlled phases is contrasted by their identical chemical building unit composition.

There is currently a push towards big data and data mining in materials research to accelerate discovery. Zeolites, metal-organic frameworks and other related crystalline porous materials are not immune to this phenomenon, as evidenced by the proliferation of porous structure databases and computational gas-adsorption screening studies over the past decade. The endeavour to identify the best materials for various gas separation and storage applications has led not only to thousands of synthesized structures, but also to the development of algorithms for building hypothetical materials. The materials databases assembled with these algorithms contain a much wider range of complex pore structures than have been synthesized, with the reasoning being that we have discovered only a small fraction of realizable structures and expanding upon these will accelerate rational design. In this Review, we highlight the methods developed to build these databases, and some of the important outcomes from large-scale computational screening studies.

The legislative changes needed to introduce non-medical prescribing (NMP) in Northern Ireland (NI) involve both UK wide legislation and NI Regulations. Resultantly, some timing differences exist in the adoption of NMP legislation between GB and NI to allow the devolved administration to adopt relevant legislation locally. This Chapter considers the development of the local legislation in terms of supplementary and independent NMP with respect to pharmacists, nurses, physiotherapists, podiatrists, radiographers and optometrists.A summary of the current prescribing status of each profession in NI is outlined by members of those professions. This highlights the progression of NMP across the professions, with several hundred pharmacists and nurses qualified and registered as NMPs, and the more recent professions to gain prescribing rights, such as optometrists, where fewer than 20 are currently registered as NMPs in NI. However, it is acknowledged that qualification and registration alone are not indicators of NMP activity and benefits and so the key achievements of active prescribers are considered where possible.The Chapter concludes positively with an outline of what the future of NMP in NI may entail for each of those professions.

© 2017 American Chemical Society. Pore volume is one of the main properties for the characterization of microporous crystals. It is experimentally measurable, and it can also be obtained from the refined unit cell by a number of computational techniques. In this work, we assess the accuracy and the discrepancies between the different computational methods which are commonly used for this purpose, i.e, geometric, helium, and probe center pore volumes, by studying a database of more than 5000 frameworks. We developed a new technique to fully characterize the internal void of a microporous material and to compute the probe-accessible and -occupiable pore volume. We show that, unlike the other definitions of pore volume, the occupiable pore volume can be directly related to the experimentally measured pore volumes from nitrogen isotherms.

International audience; Precision ultrasonic measurements in binary gas systems provide continuous real-time monitoring of mixture composition and flow. Using custom microcontroller-based electronics, we have developed sonar instruments, with numerous potential applications, capable of making continuous high-precision sound velocity measurements. The instrument measures sound transit times along two opposite directions aligned parallel to - or obliquely crossing - the gas flow. The difference between the two measured times yields the gas flow rate while their average gives the sound velocity, which can be compared with sound velocity vs. molar composition look-up curves to obtain the binary mixture at a given temperature and pressure. The look-up curves may be generated from prior measurements in known mixtures of the two components, from theoretical calculations, or from a combination of the two. We describe the instruments and their performance within numerous applications in the ATLAS experiment at the CERN Large Hadron Collider (LHC). The instruments can be of interest in other areas where continuous in-situ binary gas analysis and flowmetry are required.

Custom ultrasonic instruments have been developed for simultaneous monitoring of binary gas mixture and flow in the ATLAS Inner Detector. Sound transit times are measured in opposite directions in flowing gas. Flow rate and sound velocity are respectively calculated from their difference and average. Gas composition is evaluated in real-time by comparison with a sound velocity/composition database, based on the direct dependence of sound velocity on component concentrations in a mixture at known temperature and pressure. Five devices are integrated into the ATLAS Detector Control System. Three instruments monitor coolant leaks into N2 envelopes of the silicon microstrip and Pixel detectors. Resolutions better than ±2×10−5±2×10−5 and ±2×10−4±2×10−4 are seen for C3F8 and CO2 leak concentrations in N2 respectively. A fourth instrument detects sub-percent levels of air ingress into the C3F8 condenser of the new thermosiphon coolant recirculator. Following extensive studies a fifth instrument was built as an angled sound path flowmeter to measure the high returning C3F8 vapour flux View the MathML source(∼1.2kgs−1). A precision of

Designing Carbon Dioxide Traps One widely discussed means of stemming the rise in atmospheric carbon dioxide concentration is to capture the gas prior to its emission and then bury it. The materials currently known to best adsorb CO 2 for this purpose tend to involve amine groups; however, the precise molecular details of adsorption often remain murky, and rational improvement of sorbent properties by structural modification has been challenging. Vaidhyanathan et al. (p. 650 ; see the Perspective by Lastoskie ) have crystallographically resolved the binding motifs of CO 2 in an amine-bearing metal-organic framework solid. Accompanying theoretical simulations matched the experimental observations.

The CETP inhibitor, torcetrapib, was prematurely terminated from phase 3 clinical trials due to an increase in cardiovascular and noncardiovascular mortality. Because nearly half of the latter deaths involved patients with infection, we have tested torcetrapib and other CETPIs to see if they interfere with lipopolysaccharide binding protein (LBP) or bactericidal/permeability increasing protein (BPI). No effect of these potent CETPIs on LPS binding to either protein was detected. Purified CETP itself bound weakly to LPS with a Kdor= 25 microM compared with 0.8 and 0.5 nM for LBP and BPI, respectively, and this binding was not blocked by torcetrapib. In whole blood, LPS induced tumor necrosis factor-alpha normally in the presence of torcetrapib. Furthermore, LPS had no effect on CETP activity. We conclude that the sepsis-related mortality of the ILLUMINATE trial was unlikely due to a direct effect of torcetrapib on LBP or BPI function, nor to inhibition of an interaction of CETP with LPS. Instead, we speculate that the negative outcome seen for patients with infections might be related to the changes in plasma lipoprotein composition and metabolism, or alternatively to the known off-target effects of torcetrapib, such as aldosterone elevation, which may have aggravated the effects of sepsis.

A model of coping with stress is proposed in which coping mediates the relationship among organizational stressors and personal characteristics, and job-related strains and organizational outcomes. Study results, based on a sample of professional salespeople, provide overall support for most of the hypothesized relationships among work-related stressors, personal characteristics, and coping styles. Findings also support the influence of emotion-focused coping on the psychological outcomes of emotional exhaustion and job-induced anxiety; which in turn are found to influence job satisfaction and intention to withdraw. While problem-focused coping had no effect on job-induced anxiety, problem-focused coping did effect emotional exhaustion, which in turn influences job satisfaction and intention to withdraw. Minor differences were found when the proposed model was applied to saleswomen versus salesmen. Overall, however, the model was robust across both genders.

Novel fluorescent derivatives of serotonin have been synthesized and used as tracers for the development of a 5-HT2C fluorescence polarization assay. Serotonin analogs that feature a fluorescent probe attached through an ether linkage at the tryptamine 5-position have high affinity for the 5-HT2C receptor, and affinity is dependent on both linker length and pendent dye. These variables have been optimized to generate Cy3B derivative 5a, which has 10-fold higher 5-HT2C affinity relative to serotonin (Kd=0.23 nM). In receptor activation experiments, 5a acts as a full agonist of 5-HT2C. Upon binding to 5-HT2C cell membranes, 5a shows a robust increase in fluorescence polarization (FP) signal. In an FP binding assay using 5a as a tracer ligand, Ki values for known 5-HT2C agonists and antagonists showed excellent agreement with Ki values from radioligand binding (r2=0.93). The FP ligand assay is suitable for high-throughput drug screening applications with respect to speed of analysis, displaceable signal, precision, and sensitivity to various reagents. A 384-well-based high-throughput assay that is rapid, economical, and predictive of test compounds' ability to bind to the 5-HT2C receptor has been compiled and validated.

Team learning is growing rapidly in popularity in United States (U.S.) and Mexican universities. This instructional approach consists of using learning teams in which participants are required to work together regularly for a semester period of time and produce evaluated team outcomes. These team outcomes, along with their individual performance, have a significant impact on each individual's final assessment. We compare team processes, team conflict, team outcomes, and gender interaction in Mexican and U.S. student teams. U.S. teams report more team-oriented behavior and more cohesiveness, and Mexican teams report more self-oriented behavior and more conflict. Nationality (United States or Mexico) has a moderating effect on the relationship between gender heterogeneity and cohesiveness and conflict. Suggestions are given for applications and future research.

A relation is derived between the mismatch strain, the film thickness, and the displacement of a linear elastic structure under external loading during material deposition. If any two of these variables can be experimentally determined, then the remaining variable can be determined. The method allows one to experimentally determine the mismatch strain by measuring the film thickness and the displacement of a point on the structure that is not undergoing deposition. The intrinsic stresses can be used to self-assemble microstructures during material deposition. Assembly of two components is considered: one component is subjected to deposition and is modeled as an Euler-Bernoulli beam, and the other component is not subjected to deposition and is modeled as a linear spring. For the purposes of this paper, the definition of assembly requires that the beam do work on the spring. The analysis is experimentally verified by electroplating nickel onto an AFM cantilever beam in contact with a second AFM beam (serving as the spring) that does not undergo deposition.

Hormone signaling is often pulsatile, and multiparameter deconvolution procedures have long been used to identify and characterize secretory events. However, the existing programs have serious limitations, including the subjective nature of initial peak selection, lack of statistical verification of presumed bursts, and user-unfriendliness of the application. Here we describe a novel deconvolution program, AutoDecon, which addresses these concerns. We validate AutoDecon for application to serum luteinizing hormone (LH) concentration time series using synthetic data mimicking real data from normal women and then comparing the performance of AutoDecon with the performance of the widely employed hormone pulsatility analysis program Cluster. The sensitivity of AutoDecon is higher than that of Cluster ( approximately 96% vs. 80%, P=0.001). However, Cluster had a lower false-positive detection rate than did AutoDecon (6% vs. 1%, P=0.001). Further analysis demonstrated that the pulsatility parameters recovered by AutoDecon were indistinguishable from those characterizing the synthetic data and that sampling at 5- or 10-min intervals was optimal for maximizing the sensitivity rates for LH. Accordingly, AutoDecon presents a viable nonsubjective alternative to previous pulse detection algorithms for the analysis of LH data. It is applicable to other pulsatile hormone concentration time series and many other pulsatile phenomena. The software is free and downloadable at http://mljohnson.pharm.virginia.edu/home.html.

A planar electrode containing cylindrical pores with semi-circular ends is modeled using a finite element implementation of the transient nonlinear 2D Nernst– Planck–Poisson-modified Stern (NPPMS) model. The model uses a modified Stern layer to account for finite ion size. The study includes the effects of pore radius and depth on the predicted electric potential, ion concentration, surface charge density, surface energy density, and charging time. The ion concentration and electric potential are found to be sensitive to the change in radii of the pore and insensitive to the pore depth. The surface charge density is slightly higher within the pore than along the vertical flat regions of the electrode. The increase in surface area due to porosity increases the charging time.

Cholesteryl ester transfer protein (CETP) transfers neutral lipids between different types of plasma lipoprotein. Inhibitors of CETP elevate the fraction of plasma cholesterol associated with high-density lipoproteins and are being developed as new agents for the prevention and treatment of cardiovascular disease. The molecular basis of their function is not yet fully understood. To aid in the study of inhibitor interactions with CETP, a torcetrapib-related compound was coupled to different biotin-terminated spacer groups, and the binding of CETP to the streptavidin-bound conjugates was monitored on agarose beads and in a surface plasmon resonance biosensor. CETP binding was poor with a 2.0 nm spacer arm, but efficient with polyethyleneglycol spacers of 3.5 or 4.6 nm. The conjugate based on a 4.6 nm spacer was used for further biosensor experiments. Soluble inhibitor blocked the binding of CETP to the immobilized drug, as did preincubation with a disulfide-containing covalent inhibitor. To provide a first estimate of the binding site for torcetrapib-like inhibitors, CETP was modified with a disulfide-containing agent that modifies Cys-13 of CETP. Mass spectrometry of the modified protein indicated that a single half-molecule of the disulfide was covalently bound to CETP, and peptide mapping after digestion with pepsin confirmed previous reports based on mutagenesis that Cys-13 was the site of modification. Modified CETP was unable to bind to the biosensor-mounted torcetrapib analog, indicating that the binding site on CETP for torcetrapib is in the lipid-binding pocket near the N-terminus of the protein. The crystal structure of CETP shows that the sulfhydryl group of Cys-13 resides at the bottom of this pocket.