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The photoinduced rearrangement reaction mechanism of 1,2,3-thiadiazole remains experimentally elusive. Two possible mechanisms have been proposed to date. The first is a stepwise mechanism via a thiocarbene intermediate; the second is an excited-state concerted rearrangement mechanism. Herein we have adopted both the electronic structure calculations and nonadiabatic dynamics simulations to study the photoinduced rearrangement reactions of 1,2,3-thiadiazole in the S2, S1, and S0 states in solution. On the basis of QM(CASPT2)/MM [quantum mechanics(complete active space self-consistent field second-order perturbation theory)/molecular mechanics] calculations, we have found that (1) the thiocarbene intermediate is not stable; thus, the stepwise mechanism should be unfavorable; (2) the excited-state decay from the S2 via S1 to S0 state is ultrafast and completed within ca. 200 fs; therefore, both the S2 and S1 states should not have a long enough time for the excited-state rearrangements. Instead, we have computationally proposed a modified photoinduced rearrangement mechanism. Upon irradiation, the S2 state is first populated (114.0 kcal/mol), followed by an ultrafast S2→S1→S0 excited-state decay along the S--N bond fission, which eventually leads to a very "hot" intermediate with the S--N bond broken (18.3 kcal/mol). Then, thermal rearrangements to thioketene, thiirene, and ethynethiol occur in a concerted asynchronous way. This mechanistic scenario has been verified by full-dimensional trajectory-based nonadiabatic dynamics simulations at the QM(CASPT2)/MM level. Finally, our present computational work provides experimentally interesting mechanistic insights into the photoinduced rearrangement reactions of cyclic and acyclic diazo compounds. [ABSTRACT FROM AUTHOR]

We measured equilibrium constants for H3O+(H2O)n-1 + H2O ↔ H3O+(H2O)n (n = 4-9) reactions taking place in an ion drift tube with various applied electric fields at gas temperatures of 238-330 K. The zero-field reaction equilibrium constants were determined by extrapolation of those obtained at non-zero electric fields. From the zero-field reaction equilibrium constants, the standard enthalpy and entropy changes, ΔH0n,n-1 and ΔS0n,n-1, of stepwise association for n = 4-8 were derived and were in reasonable agreement with those measured in previous studies. We also examined the electric field dependence of the reaction equilibrium constants at non-zero electric fields for n = 4-8. An effective temperature for the reaction equilibrium constants at non-zero electric field was empirically obtained using a parameter describing the electric field dependence of the reaction equilibrium constants. Furthermore, the size dependence of the parameter was thought to reflect the evolution of the hydrogen-bond structure of H3O+(H2O)n with the cluster size. The reflection of structural information in the electric field dependence of the reaction equilibria is particularly noteworthy. [ABSTRACT FROM AUTHOR]

After the engineering rock mass has been affected by comprehensive effects of mining and disturbance, it experiences an input of external energy as well as dissipation and release of internal energy. From the viewpoint of energy, characteristics of rock failure are studied, and the law of rock unstable deformation and energy evolution is analyzed. The damage mechanism of rock is revealed easily. A gradual loading and unloading test of fractured rock is carried out to analyze deformation characteristics of the fractured rock during the load- -bearing process, and to study the law of energy dissipation and release under different load- ing and unloading stress levels. The results show that: (1) the load-bearing time, loading and unloading stress level, stress at crack initiation and peak stress of fractured rock gradually decrease with an increase in the number of cracks, and the descending speed decreases grad- ually with the increase in the number of cracks; (2) the strain at crack initiation and peak strain of the fractured rock increase gradually with an increase in the number of cracks, and the gathering speed decreases with the increase of the number of cracks; (3) the released strain energy and dissipation energy of fractured rock increase with an increase of loading and unloading stress levels, and the increasing rate gradually slows down; (4) the number of acoustic emission events is positively related to the degree of rock damage, and the increase in the number of cracks will prolong duration of the number of acoustic emission events. The results have a theoretical value for energy evolution and deformation damage of fractured rock masses, and also provide experimental experience to study the instability precursor information of rock materials from the viewpoint of energy. [ABSTRACT FROM AUTHOR]

Precise band-mapping in organic pn-homojunctions, for various doping concentrations of the p- and n-type layers, was performed by measuring the film thickness dependence of the work function on both sides of the pn-homojunction interface using a Kelvin probe. Band-bending, including that in an underlying n-type layer induced by the stepwise deposition of a p-type layer, and vice versa, needs to be taken into account, together with the electric potential distribution derived from Poisson's equation, in order to precisely calculate the work function. The conventional theory for the space charge layer suggests that the dopants are spatially fixed even in organic semiconductor films. [ABSTRACT FROM AUTHOR]

Ionic solutions exhibiting multiple association are described within the binding mean spherical approximation (BiMSA). This model is based on the Wertheim formalism, in the framework of the primitive model at the McMillan-Mayer level. The cation and the anion form the various complexes according to stepwise complexation-equilibria. Analytic expressions for the Helmholtz energy, the internal energy, the speciation, and for the osmotic and activity coefficients are given considering a binary solution with an arbitrary number of association sites on one type of ion (polyion) and one site on the ions of opposite sign (counterions). As an alternative, mean field expressions, as developed in SAFT-type theories, are also presented. The result obtained from the latter approximate method exhibits a reasonable agreement with those from BiMSA for the speciation, and a remarkable one for the osmotic coefficient. [ABSTRACT FROM AUTHOR]

Purpose: Dentin caries constitute a complex ecosystem with a diverse microbiota adapted to fluctuations in nutrient concentration and acidity. However, knowledge about the acid tolerant microbiota at different levels in the lesion is rather poor. Hence, the purpose of this study was to investigate the acid tolerant microflora at different levels in established dentin caries lesions using solid pH-selective media. Materials and Methods: Primary dentin caries lesions were sampled with a bur at three levels (superficial, centre and the clinically caries-free floor of the lesion) in 10 patients. Samples were incubated on pH-neutral and pH-selective (pH 4.0, 4.5, 5.0, 5.5) agars. Numbers of colony-forming units (cfu) were determined and colonies were subsequently characterised morphologically and isolated. Results: The total number of bacteria in the carious lesions, recovered using blood agar (BA), ranged from 5.88 x 10³ to 5.85 x 105 (median 2.64 x 105; range 5.80 x 105) and numbers of recovered bacteria decreased with decreasing agar pH. Fewer bacteria were found in the clinically caries-free dentin (P = 0.042), but the mean number of cfu (BA) was still 5.88 x 10³ in those samples. Conclusion: Each of the 10 investigated dentin caries lesions harboured a unique microbial flora, indicating that various combinations of aciduric bacteria can colonise, survive in and probably propagate dentin caries. Solid pH-selective agars can be used successfully to select acid-tolerant microorganisms in dentin caries lesions. This could be used to describe this subset of the total microbiome from a phenotypic point of view, an objective that cannot be accomplished using molecular methods. [ABSTRACT FROM AUTHOR]

Equilibrium thermochemical measurements using an ion mobility drift cell technique have been utilized to investigate the binding energies and entropy changes associated with the stepwise hydration of the biologically significant ions pyrimidine radical cation and protonated pyrimidine. The binding energy of the hydrated pyrimidine radical cation is weaker than that of the proton-bound dimer pyrimidineH+(H2O) consistent with the formation of a weak carbon-based CHδ+··OH2 hydrogen bond (11.9 kcal/mol) and a stronger NH+··OH2 hydrogen bond (15.6 kcal/mol), respectively. Other proton-bound dimers such as pyrimidineH+(CH3OH) and pyrimidineH+(CH3CN) exhibit higher binding energies (18.2 kcal/mol and 22.8 kcal/mol, respectively) due to the higher proton affinities and dipole moments of acetonitrile and methanol as compared to water. The measured collisional cross sections of the proton-bound dimers provide experimental-based support for the DFT calculated structures at the M06-2x/6-311++G (d,p) level. The calculations show that the hydrated pyrimidine radical cation clusters form internally solvated structures in which the water molecules are bonded to the C4N2H4•+ ion by weak CHδ+··OH2 hydrogen bonds. The hydrated protonated pyrimidine clusters form externally solvated structures where the water molecules are bonded to each other and the ion is external to the water cluster. Dissociative proton transfer reactions C4N2H4•+(H2O)n-1 + H2O → C4N2H3• + (H2O)nH+ and C4N2H5+(H2O)n-1 + H2O → C4N2H4 + (H2O)nH+ are observed for n ≥ 4 where the reactions become thermoneutral or exothermic. The absence of the dissociative proton transfer reaction within the C4N2H5+(CH3CN)n clusters results from the inability of acetonitrile molecules to form extended hydrogen bonding structures such as those formed by water and methanol due to the presence of the methyl groups which block the extension of hydrogen bonding networks. [ABSTRACT FROM AUTHOR]

Classic rotating engines are powerful and broadly used but are of complex design and difficult to miniaturize. It has long remained challenging to make large-stroke, high-speed, high-energy microengines that are simple and robust. We show that torsionally stiffened shape memory nanocomposite fibers can be transformed upon insertion of twist to store and provide fast and high-energy rotations. The twisted shape memory nanocomposite fibers combine high torque with large angles of rotation, delivering a gravimetric work capacity that is 60 times higher than that of natural skeletal muscles. The temperature that triggers fiber rotation can be tuned. This temperature memory effect provides an additional advantage over conventional engines by allowing for the tunability of the operation temperature and a stepwise release of stored energy. [ABSTRACT FROM AUTHOR]

Abstract Spectroscopic data generated by several PAT technologies is routinely used for the rapid assessment of quality properties in several industrial sectors, such as agrofood, beverages, pharmaceutics, chemicals, pulp & paper, etc. While spectra can easily provide hundreds of measurements across several wavelengths, only a fraction of the collected spectrum conveys relevant information to predict the property of interest. Therefore, the performance of current models is highly related with the ability to select key wavebands, for which the existence of prior knowledge cannot be always secured. Therefore, several feature selection procedures consisting of variants of interval partial least squares (iPLS) have been proposed. These methodologies are however solely focused on determining the most relevant wavebands and do not attempt to further enhance the prediction capabilities within each interval. On the other hand, standard full-spectrum models are often improved by reducing the spectral resolution, but this operation has not been yet synergistically integrated together with waveband selection. As spectral aggregation can effectively improve modelling performance, a multiresolution selection algorithm that simultaneously selects the most relevant wavebands and their optimal resolution is here proposed. By design, this methodology leads to prediction models that are at least as good as the full-spectrum models. The performance comparison made on simulated data and real NIR spectra of gasoline samples also shows that the proposed methodology outperforms iPLS and its variants based on forward and backward selection of intervals in a statistically significant way. Highlights • MR-iPLS is able to simultaneously select wavebands and optimize their local resolution. • Derived models are bound to be at least as good as the full-spectrum models. • Case study illustrates improved performance of several iPLS algorithms. [ABSTRACT FROM AUTHOR]

Highlights • Two sugar reduction strategies (gradual and stepwise) were compared using grape nectars. • 6–12 year old children evaluated the nectars once a week over a 9-week period. • Sensory and hedonic perception was evaluated. • Gradual sugar reduction caused smaller changes in children’s sensory and hedonic perception. Abstract Excessive sugar consumption has been identified as the main dietary determinants of obesity among children and adolescents. Sugar sweetened beverages are one of the main sources of added sugar in the diet. Therefore, gradual sugar reduction in these products can contribute to decreasing sugar intake and encourage children to slowly develop preference for products with lower sugar concentration. However, specific recommendations on how to implement gradual sugar reduction programs are still lacking. The aim of the present study was to compare two sugar reduction strategies (stepwise vs. gradual) on children’s sensory and hedonic perception of grape nectar. One hundred and seventeen 6–12 years old children participated in a two-part study: a 9-week study and a final liking test at the end of 11 weeks. In the 9-week study, children were divided in two sugar reduction strategies: stepwise and gradual. Children’s sensory and hedonic perception was evaluated using 9-point hedonic scales and check-all-that-apply questions. There were no major differences between the gradual and stepwise reduction groups in children’s sensory and hedonic perception. However, results showed that the gradual reduction strategy led to smaller changes in children’s sensory and hedonic perception than the stepwise strategy. In the final test, children in the stepwise group gave significantly higher liking scores to the samples than those in the gradual sugar reduction strategy. Comparing the overall liking between the first time the children tasted the grape nectars and the final test, a significant difference was observed for the sample with lower sugar content only for the stepwise group, which was higher in the 11th week. Although differences between the sugar reduction strategies were small, the gradual reduction strategy seems to be recommended over the step-wise strategy. [ABSTRACT FROM AUTHOR]

1,3,5,7‐Tetranitro‐1,3,5,7‐tetraazacyclooctane(HMX) is one of the most powerful and widely used explosives. A new method for the synthesis of HMX from 3,7‐dipropionyl‐1,3,5,7‐tetraazabicyclo[3.3.1]nonane (DPPT) was investigated. Two important intermediates, 1,5‐dipropionyl‐3‐nitroso‐7‐nitro‐1,3,5,7‐tetraazacyclooctane (DPNNO) and 1,5‐dipropionyl‐3,7‐dinitro‐1,3,5,7‐tetraazacyclooctane (DPDN), were isolated from the reaction mixture. The reaction mechanism, involving a nitrolysis‐nitrosolysis‐nitrolysis‐nitrolysis process, was proposed and verified by the 1H‐NMR tracking. Based on the reaction mechanism, a stepwise method to prepare HMX from DPPT was developed. DPPT could be efficiently and smoothly converted to DPNNO in red fuming nitric acid with excellent yield up to 94.2 %. The influence factors on the yields of HMX such as reaction temperature, loading amounts of N2O5 were investigated. Under the optimized conditions, HMX was obtained with a satisfactory yield of 85.0 %. The overall yield of the stepwise procedure was as high as 80.0 %. [ABSTRACT FROM AUTHOR]

Pillar[n]quinones and pillar[n‐m]arene[m]quinones are oxidation products of pillar[n]arenes. Their molecular structure resembles the parent compounds. However, their map of electron density is different. Each 1,4‐benzoquinone ring, which replaces a 1,4‐dialkoxy‐substituted benzene ring decreases the electron density in the interior cavity and increases the electron density on the upper and lower rim of the pillar. The electron donor character is stepwise transformed to an electron acceptor status. This effect alters the complexation tendencies, which are the most interesting properties of these macrocyclic host systems. [ABSTRACT FROM AUTHOR]

Abstract Step-wise reaction of CdO, Bi 2 O 3 , and Cd(NO 3) 2 ·4H 2 O leads to formation of a novel bismuth oxide nitrate, CdBiO 2 NO 3 , which completes the family of bismuthite-like MIIBiO 2 NO 3 oxide nitrates. The new compound is tetragonal, I 4/ mmm , a = 3.9486(1)Å, c = 14.2235(2)Å; its crystal structure resembles those of PbBiO 2 NO 3 and CaBiO 2 NO 3 , except for, probably, different positioning of the nitrate group. The compound is stable until ∼425 °C when it decomposes, in one step, into CdO and a mixture of Bi–Cd oxides. Cd-based analogs of isostructural PbLnO 2 NO 3 (Ln – lanthanides) oxide nitrates are unlikely to exist. We discuss the similarities and differences in the structures of layered oxyhalides and oxynitrates of bismuth and rare-earths. Graphical abstract Image 1 Highlights • New layered bismuth oxide nitrate CdBiO 2 NO 3 was prepared via two-step reaction. • Its tetragonal crystal structure resembles those of PbBiO 2 NO 3 and CaBiO 2 NO 3. • The compound was characterized by powder XRD, IR spectroscopy and thermally. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The aim of this study was to isolate and identify lipolytic bacteria. Perform a statistical stepwise physicochemical optimization for maximum production of extracellular lipase and its validation in a bioreactor. Methods and Results: Several lipolytic bacteria were isolated from petroleum hydrocarbon‐polluted soil. The strain expressing the highest lipase activity (47 U ml−1) was genetically identified as Gram‐positive Bacillus stratosphericus PSP8 (NCBI GenBank accession no. MH120423). The response surface methodology (RSM)–central composite face centre (CCF) design of experiments was performed based on the preselected levels of the studied parameters obtained from the performed one‐factor‐at‐a‐time sequential experiments. A second‐order polynomial model was predicted and improved the lipase production by approximately 1·6‐fold. Preliminary scaling up of the validated optimized process was carried out in a batch 10‐l stirred tank bioreactor, applying the optimum predicted operating conditions; pH 6·98, 34·8°C, 2·2 × 106 cells per ml, 200 rev min−1, 4·82 g l−1 tributyrine concentration, 1% sucrose and 0·1% yeast extract. This yielded 89 U ml−1 at the late log phase of bacterial growth (48 h). Logistic kinetic model effectively characterized the submerged fermentation process, and the maximum specific growth and lipase production rates were estimated to be 0·338 and 0·164 h−1 respectively. Conclusions: The mesophilic and neutrophilic B. stratosphericus PSP8 isolated from petroleum hydrocarbon‐contaminated soil is a proper source of lipase. The closeness of the predicted response with that of the experimental value and the enhancement of lipase productivity in fermenter scale by approximately 1·9‐fold, showed that statistically optimized design can be used in order to improve the lipase production to meet the increasing demand. Significance and Impact of the Study: The RSM‐CCF statistical optimization is useful for optimizing a large number of variables and studying their interactive effects on extracellular lipase production. [ABSTRACT FROM AUTHOR]

Frontal affinity chromatography is an efficient technique that combines affinity interaction and high-performance liquid chromatography, and frontal analysis has been used in studying the interaction between drugs and proteins. Based on frontal analysis, stepwise frontal analysis has been established. The present study aimed to use the Lineweaver-Burk plot in stepwise frontal analysis by taking the weighted average of time data. Commercial human serum albumin (HSA) and alpha-1-acid glycoprotein (AGP) columns were used as an affinity column. Warfarin and digitoxin were chosen as model drugs for the HSA column, whereas verapamil and tamsulosin were selected as model drugs for the AGP column. The time data obtained by frontal analysis and stepwise frontal analysis were compared, and the results revealed good correlation (r2 = 0.9946-0.9998). Frontal analysis and stepwise frontal analysis were also used to analyze the equilibrium dissociation constants (Kd) of model drugs on the HSA and AGP columns. The Kd values were compared with literature values, which revealed the same order of magnitude. These results illustrate that conversion of the time data is reasonable and feasible. The Lineweaver-Burk plot can be used in the stepwise frontal analysis model to study the characteristics of the interaction between drugs and proteins.ᅟ [ABSTRACT FROM AUTHOR]

Controlling fluidic stepwise waveforms is important in many applications of medical science, biology, and chemistry. However, such a control is implemented by automated, yet expensive, dynamic controllers hindering broad use of these systems. This study presents a stepwise waveform generator (SWG) that achieves stepwise pressure variation using constant water-head pressure only. SWG consists of a microfluidic oscillator and a diode pump, autonomously converts constant pressure to pulsatile pressure via the oscillator, and then generates stepwise increasing or decreasing pressures via the diode pump. The step size, and duration time of the pressure step, can be set independently to take values within the range of 215–431 Pa and 26–181 s, respectively. With the use of additional valves, SWG can regulate flow rate, wall shear stress, and reagent concentration, in a stepwise manner, thereby opening new avenues for the applicability of this self-controlled device. [ABSTRACT FROM AUTHOR]

The thermal properties of cellulose, hemicellulose and lignin can be utilized to improve the characteristics of pyrolysis liquids. In this study, a concept of stepwise pyrolysis to fractionate the liquid based on the thermal properties of the biomass constituents was investigated. Lignocellulosic biomass was thermally treated in two steps: 200–300 °C followed by 550 °C. Derived liquids were studied for GC/MS analysis, water content, acid concentration and a solvent extraction method. Pyrolytic liquid derived from 550 °C after treatment at lower temperatures have a higher relative composition of phenolic compounds compared to one-step pyrolysis (increased from 58 to 90% of GC/MS peak area). Also, compounds known to promote aging, such as acids and carbonyl compounds, are derived at lower temperatures which may suppress aging in the liquid derived downstream at 550 °C. For liquids derived at 550 °C, the total acid number was reduced from 125 in one-step treatment to 14 in two-step treatment. Overall, no significant difference in the total liquid yield (sum of the liquids derived in separated treatments) nor any variations in their collective composition compared to one-step treatment at 550 °C was observed, i.e. stepwise pyrolysis can be utilized for direct fractionation of pyrolytic vapors. [ABSTRACT FROM AUTHOR]

A stepwise mechanism for the isomerization of n-pentane into 2-methylbutane on a bifunctional palladium-containing mordenite catalyst is proposed and a corresponding kinetic model is built. Kinetic experiments are performed in a flow catalytic reactor. During the experiments, the reactor pressure varied from 10 to 30 atm, the reactor temperature varied from 603 to 640 K, and the hydrogen/n-pentane molar ratio varied from 2 to 10. The contact time (the ratio of the catalyst weight to the mass flow rate of the raw material) varied from 0.5 to 2 h. From the data of the kinetic experiment, the kinetic constants of the model and the constants of the distribution density of the observation errors are estimated by the maximum likelihood (ML) method. A sequential design of the kinetic experiment is implemented in order to precisely estimate the model constants and the kinetic model allowing us to predict the experimental results with an accuracy exceeding that of the starting experiments. The model is shown to be adequate for the experimental data obtained. [ABSTRACT FROM AUTHOR]

Variable selection plays a fundamental role in high-dimensional data analysis. Various methods have been developed for variable selection in recent years. Well-known examples are forward stepwise regression (FSR) and least angle regression (LARS), among others. These methods typically add variables into the model one by one. For such selection procedures, it is crucial to find a stopping criterion that controls model complexity. One of the most commonly used techniques to this end is cross-validation (CV) which, in spite of its popularity, has two major drawbacks: expensive computational cost and lack of statistical interpretation. To overcome these drawbacks, we introduce a flexible and efficient test-based variable selection approach that can be incorporated into any sequential selection procedure. The test, which is on the overall signal in the remaining inactive variables, is based on the maximal absolute partial correlation between the inactive variables and the response given active variables. We develop the asymptotic null distribution of the proposed test statistic as the dimension tends to infinity uniformly in the sample size. We also show that the test is consistent. With this test, at each step of the selection, a new variable is included if and only if the p -value is below some pre-defined level. Numerical studies show that the proposed method delivers very competitive performance in terms of variable selection accuracy and computational complexity compared to CV. [ABSTRACT FROM AUTHOR]

An efficient green synthesis of novel 3-(4-aminothieno[2,3-d]pyrimidin-5-yl)coumarins has been developed. One-pot reaction of 3-acetylcoumarin, malononitrile, and elemental sulfur, catalyzed by L-proline, resulted in the formation of thiophene derivatives, which were used as precursors for the synthesis of 3-(4-aminothieno[2,3-d]pyrimidin-5-yl)coumarins. Target compounds were prepared by a one-pot method or stepwise, and NH4OAc was exploited as a reagent and molten salt. Microwave irradiation method was successfully applied to afford the products in excellent yields. [ABSTRACT FROM AUTHOR]

Bile salts are facially amphiphilic, naturally occurring chemicals that aggregate to perform numerous biochemical processes. Because of their unique intermolecular properties, bile salts have also been employed as functional materials in medicine and separation science (e.g., drug delivery, chiral solubilization, purification of single-walled carbon nanotubes). Bile micelle formation is structurally complex, and it remains a topic of considerable study. Here, the exposed functionalities on the surface of cholate and deoxycholate micelles are shown to vary from one another and with the micelle aggregation state. Collectively, data from NMR and capillary electrophoresis reveal preliminary, primary, and secondary stepwise aggregation of the salts of cholic (CA) and deoxycholic (DC) acid in basic conditions (pH 12, 298 K), and address how the surface availability of chirally selective binding sites is dependent on these sequential stages of aggregation. Prior work has demonstrated sequential CA aggregation (pH 12, 298 K) including a preliminary CMC at ca. 7 mM (no chiral selection), followed by a primary CMC at ca. 14 mM that allows chiral selection of binaphthyl enantiomers. In this work, DC is also shown to form stepwise preliminary and primary aggregates (ca. 3 mM DC and 9 mM DC, respectively, pH 12, 298 K) but the preliminary 3 mM DC aggregate is capable of chirally selective solubilization of the binaphthyl enantiomers. Higher-order, secondary bile aggregates of each of CA and DC show significantly degraded chiral selectivity. Diffusion NMR reveals that secondary micelles of CA exclude the BNDHP guests, while secondary micelles of DC accommodate guests, but with a loss of chiral selectivity. These data lead to the hypothesis that secondary aggregates of DC have an exposed binding site, possibly the 7a-edge of a bile dimeric unit, while secondary CA micelles do not present binding edges to the solution, potentially instead exposing the three alcohol groups on the hydrophilic α-face to the solution. [ABSTRACT FROM AUTHOR]

Monitoring biological growth of field crops is important for planning and timing agricultural practices. In order to assess biological growth pattern of dry matter accumulation in triticale Egeyildizi triticale variety were grown in Çanakkale conditions in 2012-2013 and 2013-2014 growing seasons with continuous plant samplings from seedling emergence until seed maturation. Gompertz, Logistic, Logistic Power and Richards growth models are fitted to actual growth data and their predictions were compared. Results suggested that all sigmoidal growth models successfully explained triticale dry matter accumulation over 98 % R² values and low mean square errors, Richards model fitted best for both years with an R² value over 99 %. Dry matter accumulation were also investigated as a result of average temperature, precipitation, growth degree days and cumulative growth degree days with stepwise regression. Rresults indicated that average weather temperature had a similar pattern across both growing seasons and had a major influence on dry matter accumulation. Since Richards sigmoidal growth model may be adequately described growth pattern of triticale by generally high R² with lower Mean Square Error (MSE) values. [ABSTRACT FROM AUTHOR]

The paper discusses specifics of gas separation techniques by means of sample crushing in vacuum, and, in particular, the stepwise crushing method for studying the sources and evolution of the fluid phase of rocks and minerals. The data on the Seblyavr massif, Kola Peninsula, are employed to demonstrate that, if the age of the minerals is old enough and they contain elevated concentrations of parental elements (U, Th, and K), in situ produced noble gas components can strongly distort the composition of the initially entrapped gases and thus result in misinterpretations of the analytical data. The application of stepwise crushing technique, as well as an individualized approach to data interpretation for each of the samples, makes it possible to solve the problem. [ABSTRACT FROM AUTHOR]

It is still challenging to simultaneously distinguish general biothiols (cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) etc .) in complex redox environments, due to the lack of reliable and convenient method. Although a number of fluorescence and/or UV–vis absorption based measurements have been employed for single or multiple biothiols detection, few of them is capable of recognizing each biothiol with individual signal at the same time. We present a one-step obtained selenadiazole derivative ( 1 ) to distinguish Cys, Hcy and GSH, which not only can produce three new kind of fluorescent compounds, but also simultaneously induce different “turn-on” fluorescence emission and red-shifted absorption signals for discriminating each biothiol. With a series of systematically analyses elucidate that probe 1 possesses high sensitivity and good selectivity for the three biothiols. Furthermore, the detection mechanism was also verified via a stepwise selenium–nitrogen (Se N) bond cleavage process of probe 1 interacting with each biothiol. In the application of tracking in vitro and in vivo biothiols, probe 1 can be acted as a dual-mode fluorescent and colorimetric platform. [ABSTRACT FROM AUTHOR]

A graph is stepwise irregular (SI) if the degrees of any two of its adjacent vertices differ by exactly one. Among graphs with non-zero edge imbalance, SI graphs are least irregular. Some basic properties of SI graphs are established. [ABSTRACT FROM AUTHOR]

By controlling the terminal organic ligands, various fascinating supramolecular assemblies originating from hydrogen bonding interactions in different dimensions in a series of hexavanadate hybrids were synthesized via step-by-step organic modification. These hybrids were characterized, and their structures were determined by single-crystal X-ray diffraction. Moreover, the introduction of a rigid bridging ligand has a positive influence on the assembly of supramolecular architectures, providing a new vision for the design and synthesis of advanced inorganic–organic materials. [ABSTRACT FROM AUTHOR]

The experiment was conducted to study the rapid detection method of soluble sugar content in head cabbage by near infrared spectroscopy, partial least squares (PLS) regression and stepwise regression (SR). The experiment collected a total of 71 samples of head cabbage. The spectral data were measured by the spectrometer of ASD FieldSpec® Handheld™ 2 made in ASD Company, USA, and the vitamin C (Vc) was measured by the 2, 6 two chloro indigo titration method. The kennard-stone (K-S) method was used to divide all samples into a calibration set and a validation set according to the given ratio. First derivative (FD) and second derivative (SD) pretreatment methods were used to improve the S/N ratio so as to find the better one from them. The coefficient of determination (R2), root mean squared error of cross validation (RMSECV), and root mean squared error of prediction (RMSEP) were used to evaluate models. The samples were divided into calibration set (60 samples) and validation set (11 samples) according to the ratio of 6:1 by K-S method. Six PLS models were established by using original, FD, and SD preprocessed spectral data of preflectance and absorbance, respectively. The modeling results showed that the spectral preprocessing method using FD could well improve modeling accuracy, the R2 of the validation set with which increased from 0.85 to 0.93, and this method was thought to be the better spectral data pretreatment method in this experiment. For the spectrum after the FD treatment, 5 confidence levels (0.95, 0.975, 0.99, 0.995, 0.999 5) were set up, and SR method was used to select modeling wavelength. With the increase of confidence level, the number of selected wavelength variables decreased from 14 to 3, and then 5 multiple linear regression models were established by 5 sets of preferred wavelengths corresponding to 5 confidence levels. The R2 values were 0.91, 0.83, 0.77, 0.7 and 0.61, respectively, and the RMSECV values were 2.362 2, 3.316 3, 3.841 1, 4.125 2 and 4.962 5 mg/100 g respectively for calibration set, while the R2 values were 0.82, 0.71, 0.72, 0.75 and 0.69, respectively, and the RMSEP values were 2.121 9, 2.983 6, 2.902 4, 2.751 6 and 3.021 5 mg/100 g respectively for validation set. According to the determination coefficient and the root mean square error analysis of the calibration set and the validation set, the multiple linear regression models corresponding to 8, 6 and 5 wavelength variables were established, and the model performance was consistent for the calibration set and the validation set. The average R2 was 0.78, the average RMSECV was 3.760 9 mg/100 g for calibration set, and the average R2 was 0.73, the average RMSEP was 2.879 2 mg/100 g for validation set, which meant that using fewer wavelength variables to predict Vc content in head cabbage was practical. So the visible / short wave near infrared spectra could be used for quantitative detection of vitamin C content in head cabbage. For the PLS model, it had many wavelength variables, the information was large, and so the detection precision was high. For the multiple linear regression models with 8, 6 or 5 selected wavelength variables, with the reduction of number of wavelength variables, the R2 decreased, which could yet provide technical support for the development of portable testing instrument. Using near infrared spectroscopy analysis technique, the prediction model for the content of Vc in cabbage was established, and it could improve the working efficiency of the internal quality evaluation of the cabbage. The research provides a new approach for quality evaluation of head cabbage. [ABSTRACT FROM AUTHOR]

Background: In a previous single center study we found that a standardized drug treatment algorithm (ALGO) was more cost effective than treatment as usual (TAU) for inpatients with major depression. This report aimed to determine whether this promising initial finding could be replicated in a multicenter study.Methods: Treatment costs were calculated for two time periods: the study period (from enrolment to exit from study) and time in hospital (from enrolment to hospital discharge) based on daily hospital charges. Cost per remitted patient during the study period was considered as primary outcome.Results: 266 patients received ALGO and 84 received TAU. For the study period, ALGO costs were significantly lower than TAU (ALGO: 7 848 ± 6 065 €; TAU: 10 033 ± 7 696 €; p = 0.04). For time in hospital, costs were not different (ALGO: 14 734 ± 8 329 €; TAU: 14 244 ± 8 419 €; p = 0.617). Remission rates did not differ for the study period (ALGO: 57.9%, TAU: 50.0%; p=0.201). Remission rates were greater in ALGO (83.3%) than TAU (66.2%) for time in hospital (p = 0.002). Cost per remission was lower in ALGO (13 554 ± 10 476 €) than TAU (20 066 ± 15 391 €) for the study period (p < 0.001) and for time in hospital (ALGO: 17 582 ± 9 939 €; TAU: 21 516 ± 12 718 €; p = 0.036).Limitations: Indirect costs were not assessed. Different dropout rates in TAU and ALGO complicated interpretation.Conclusions: Treatment algorithms enhance the cost effectiveness of the care of depressed inpatients, which replicates our prior results in an independent sample. [ABSTRACT FROM AUTHOR]

In fisheries science, high number of morphometric measures (independent variables) taken from different parts of the fish complicates the estimation of the body weight (dependent variable). Therefore, the researchers are seeking for a solution facilitating the interpretation of the equations of correlation between the characteristics. One way to deal with this challenge is the dimension reduction by means of stepwise multiple regression analysis. The aim of this study is to explain total variation with the same accuracy by using fewer independent variables. To accomplish this, 12 morphometric measures from 210 individuals of Serranus cabrilla were measured to estimate the body weight. Firstly, the 95% of the variation was explained by means of multiple regression analysis by using all variables. Then, by step-wise method, the same results were achieved with fewer independent variables. Finally, the variables with inter-multicollinearity eliminated and with two remaining independent variables determination coefficients resulted as 95%. The result showed that using more variables does not create significant distinction for accuracy to estimate the body weight although; the total length and body dept was the most effective features for weight. [ABSTRACT FROM AUTHOR]

The Ge7.4Se92.6 glass was prepared by melt-quenched method. The characteristic temperatures (the strain point, annealing point, glass transition point, yielding point and soften point) were determined by thermal analysis. The result shows that the glass transition point is 52 °C; the average thermal expansion coefficient is ΔL/L0 = 3 × 10−7 * T2 + 8 × 10−6 * T − 0.0005. The specific heat of Ge7.4Se92.6 glass was measured by stepwise method. For undercooled liquid, the relation is Cpl = 0.5001 + 4.037 × 10−4T + 305.1T−2 J K−1 g−1, while for crystal, the relation is Cpc = 0.3729 + 4.503 × 10−4T + 15.71T−2 J K−1 g−1. With the result of specific heat, the Gibbs energy and the entropy curves were calculated, and the Kauzmann temperature was then determined as Tk = 250 K. [ABSTRACT FROM AUTHOR]

CO2-responsive and photopolymerizable prepolymers are designed and synthesized. Their good photopolymerization kinetics and reversible CO2 and N2 responses to a bulk state and in a solution are reported. Stepwise modulation is verified in template imprinting. Results reveal that stable and high-resolution patterns can be produced by imprinting liquid prepolymers in CO2 atmosphere, erased by warm heating, or retained permanently by chemical cross-linking through photopolymerization with the aid of a photoinitiator. By contrast, only blurry patterns are obtained in air. [ABSTRACT FROM AUTHOR]

The positive column of a gas discharge in helium is investigated for high-modulation-depth discharge current without stepwise ionization. The electron energy distribution function for different discharge current oscillation phases, the electron concentration, and the longitudinal electric field strength are measured in helium gas-discharge plasma. The electric field modulation effect and the change of the electron energy distribution function over the period at frequencies less than the reciprocal ambipolar diffusion time are detected. [ABSTRACT FROM AUTHOR]

Second-order rate constants for alkaline hydrolysis of 2-pyridyl X-substituted-benzoates ( 4a-4l) and 4-pyridyl X-substituted-benzoates ( 5a-5l) are reported. The Hammett plots are nonlinear, e.g., substrates possessing a weak electron-withdrawing group ( EWG) or an electron-donating group ( EDG) in the benzoyl moiety deviate negatively from the linear Hammett plots composed of substrates bearing a strong EWG. In contrast, the Yukawa-Tsuno plots exhibit excellent linearity with ρX = 1.57, r = 0.43, and R2 = 0.998 for the reactions of 4a-4l and ρX = 1.47, r = 0.41, and R2 = 0.999 for those of 5a-5l, indicating that the nonlinear Hammett plots are not due to a change in the rate-determining step (RDS) but are caused by ground-state (GS) stabilization through resonance interactions. The ρX values found for the reactions of 4a-4l and 5a-5l are similar to those reported previously for reactions that proceed through a stepwise mechanism with formation of an intermediate being the RDS. Small βlg values ( e.g., −0.2 ~ −0.3) calculated from the Brønsted-type correlation of rate constants with leaving-group basicity also indicate that the reactions proceed through a stepwise mechanism, in which expulsion of the leaving group occurs after the RDS. [ABSTRACT FROM AUTHOR]

Stepwise ring closing processes of platinum(II) alkynyl arkynyl bridged DTEs (OO→OC→CC) were studied theoretically with density functional theory method in this work for better understanding the Pt(II) alkynyl coordination effect on the photophysical and photochemical properties of dithienylethene (DTE). It is observed that the absorption spectrum of OO complex is red-shifted compared with that of ring-opened DTE monomer because of the decreased HOMO-LUMO gap energy. The first S 0 →S 1 absorption of OC is red shifted than that of OO and is blue shifted than that of CC complex because of the increased conjugation of the ring-closed DTE moiety. In addition, potential energy surface (PSE) studies show that the energy barrier for the ring-closing process in the ground state of Pt(II) complex is smaller than that of the isolated DTE monomer and the isomerization process is changed from endothermic to exothermic reaction. Moreover, the energy barrier for the first ring-closing process is a little larger than the second ring-closing process involved in the DTE moieties. More important, similar with that in the DTE monomers, the ring closing processes in the ionic and triplet states of Pt(II) complexes is easier than that in the neutral case. [ABSTRACT FROM AUTHOR]

Size- and shape-controlled growth of nanoscale microporous organic polymers (MOPs) is a big challenge scientists are confronted with; meanwhile, rendering these materials for in vivo biomedical applications is still scarce. In this study, a monodispersed nanometalated covalent organic polymer (MCOP, M=Fe, Gd) with sizes around 120 nm was prepared by a self-templated two-step solution-phase synthesis method. The metal ions (Fe3+, Gd3+) played important roles in generating a small particle size and in the functionalization of the products during the reaction with p-phenylenediamine (Pa). The resultant Fe-Pa complex was used as a template for the subsequent formation of MCOP following the Schiff base reaction with 1,3,5-triformylphloroglucinol (Tp). A high tumor suppression efficiency for this Pa-based COP is reported for the first time. This study demonstrates the potential use of MCOP as a photothermal agent for photothermal therapy (PTT) and also provides an alternative route to fabricate nano-sized MCOPs. [ABSTRACT FROM AUTHOR]

Twelve 2,3′-bisindolylmethanes with various substituents were investigated using electrospray ionization quadrupole time-of-flight tandem mass spectrometry in positive ion mode. A retro-[3+2] reaction was observed in the collision-induced dissociation spectra of protonated 2,3′-bisindolylmethanes for the first time. The mechanism of retro-[3+2] reaction was concerted or stepwise. For the concerted pathway, carbon–carbon bonds of a protonated compound simultaneously cracked and the m/z 208 ion ([C15H10D2N]+) was observed with hydrogen–deuterium exchange labeling. The stepwise pathway goes through 1,3-hydrogen migration twice and the m/z 208 ion ([C15H10D2N]+) and m/z 207 ion ([C15H11DN]+) were detected with deuterium labeling. In the deuterium-labeled tandem mass spectrum for one compound, only the peak at m/z 208 was present at high abundance, suggesting that the concerted pathway is more likely. In addition, the substituents have no obvious trends on the ratios of the product intensity to the base intensity, further supporting the concerted pathway. [ABSTRACT FROM AUTHOR]

The impact of the thermal interface material (TIM) layer on the performance of a stepwise varying width microchannel cooling device is analysed. A numerical model shows that the TIM layer, besides its well known negative impact on the temperature, also generates a smoothing effect on the temperature distribution. In this study, an analytical model is used to define a nondimensional parameter, called Smoothing Resistance ratio, as the quotient between the origin of the temperature non uniformities and the TIM thermal resistance that flatten the temperature distribution. The relationship between the temperature uniformity of the cooled device, expressed through the temperature standard deviation, and the Smoothing Resistance ratio is shown to be linear. These results lead to the definition of a new design procedure for this kind of cooling device, which aims to reduce the Smoothing Resistance ratio. Two solutions are identified and their drawbacks are analysed. [ABSTRACT FROM AUTHOR]

A stepwise-cluster inference (SI) model was established through introducing stepwise-cluster analysis (SCA) into the phenanthrene immobilization process at the aqueous/modified palygorskite interface. SCA has the advantages of tackling the nonlinear relationships among environmental factors and the phenanthrene sorption amount in the immobilization process. The essence of SCA is to form a tree-based classification on a series of cutting or mergence procedures under given statistical criteria. The results indicated that SI could help develop a statistical relationship between environmental variables and the phenanthrene sorption amount, where discrete and nonlinear complexities exist. During the experiment, data were randomly sampled 10 times for model calibration and verification. The R² (close to one) and root mean squared error (RMSE) (close to zero) values guaranteed the prediction accuracy of the model. Compared to other statistical methods, the calculation of R² and RMSEs showed that SI was more straightforward for describing the nonlinear relationships and precisely fitting and predicting the immobilization of phenanthrene. Through the calculation of the input effects on the output in the SI model, the influence of environmental factors on phenanthrene immobilization were ranged in descending order as: initial phenanthrene concentration, ionic strength, pH, added humic acid dose, and temperature. It is revealed that SCA can be used to map the nonlinear and discrete relationships and elucidate the transport patterns of phenanthrene at the aqueous/modified palygorskite interface. [ABSTRACT FROM AUTHOR]

Sound quality is the impression of quality that is transmitted by the sound of a device. Its importance in sound and acoustical design of consumer products no longer needs to be demonstrated. One of the challenges is the creation of a prediction model that is able to predict the results of a listening test while using metrics derived from the sound stimuli. Often, these models are either derived using linear regression on a limited set of experimenter-selected metrics, or using more complex algorithms such as neural networks. In the former case, the user-selected metrics can bias the model and reflect the engineer pre-conceived idea of sound quality while missing potential features. In the latter case, although prediction might be efficient, the model is often in the form of a black-box which is difficult to use as a sound design guideline for engineers. In this paper, preprocessing by participants clustering and three different algorithms are compared in order to construct a sound quality prediction model that does not suffer from these limitations. The lasso, elastic-net and stepwise algorithms are tested for listening tests of consumer product for which 91 metrics are used as potential predictors. Based on the reported results, it is shown that the most promising algorithm is the lasso which is able to (1) efficiently limit the number of metrics, (2) most accurately predict the results of listening tests, and (3) provide a meaningful model that can be used as understandable design guidelines. [ABSTRACT FROM AUTHOR]

Principles based on the quality of energy, namely exergy, can assist in attaining a more efficient and cleaner energy supply structure. This paper analyzes two building clusters in campus areas based on a stepwise approach with four steps according to the Rational Exergy Management Model. The clusters involve 8 buildings at the KTH Royal Institute of Technology and those in the Albano district that is a former industrial site and will become a joint campus area in Stockholm. The energy supply for the campus and urban vicinity includes a combined heat and power plant with district heating and cooling. In this context, the energy and exergy profiles of the building clusters are compared. The level of exergy match in the energy system is analyzed. Four scenarios are then devised, which involve energy savings and different shares of various supply options. These include a new biofuel unit, seawater heat pumps, large scale aquifer thermal energy storage, heat supply from solar collectors, and electricity and heat from photovoltaic thermal arrays. The present case and four scenarios are found to have exergy matches that range between 0.49 and 0.81. The scenarios indicate that savings of 16 GWh energy, 9.6 GWh exergy, and 2663 tonnes of carbon dioxide emissions are possible. The paper contributes to exergy based analyzes for campus areas and concludes with the prospect of using campus areas as pioneering case studies for advancing the transition to cleaner energy scenarios. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to investigate a relationship between the mineral content of human trabecular bone and parameters determined from compression fatigue tests at stepwise-increasing amplitude. Methods: Mineral content of trabecular bone was estimated comparing density and bone mineral density values. The relationship between the ash density, bone mineral density and factors obtained from fatigue test: fatigue life, cumulative elastic energy and cumulative energy of dissipation was determined. Results: The results from the measurements of ash density and bone mineral density show good correlation with the fatigue test results. The relationship was estimated based on the correlation coefficient R within 0.74-0.79 for the particular pairs of factors. Conclusions: The study shows that the ash density and the bone mineral density are good predictors to estimate the fatigue life of trabecular bone. The study also validates the applicability of the tests at stepwise-increasing amplitude in determining the mechanical properties of trabecular bone. [ABSTRACT FROM AUTHOR]

The objectives of this study were to quantify the effects on production performance and milk fatty acid (FA) profile of feeding dairy cows extruded linseed (EL), a feed rich in α-linolenic acid, and to assess the variability of the responses related to the dose of EL and the basal diet composition. This meta-analysis was carried out using only data from trials including a control diet without fat supplementation. The dependent variables were defined by the mean differences between values from EL-supplemented groups and values from control groups. The data were processed by regression testing the dose effect, multivariable regression testing the effect of each potential interfering factor associated with the dose effect, and then stepwise regression with backward elimination procedure with all potential interfering factors retained in previous steps. This entire strategy was also applied to a restricted data set, including only trials conducted inside a practical range of fat feeding (only supplemented diets with <60 g of fat/kg of dry matter and supplemented with <600 g of fat from EL). The whole data set consisted of 17 publications, representing 21 control diets and 29 EL-supplemented diets. The daily intake of fat from EL supplementation ranged from 87 to 1,194 g/cow per day. The dry matter intake was numerically reduced in high-fat diets. Extruded linseed supplementation increased milk yield (0.72 kg/d in the restricted data set) and decreased milk protein content by a dilutive effect (-0.58 g/kg in the restricted data set). No effect of dose or diet was identified on dry matter intake, milk yield, or milk protein content. Milk fat content decreased when EL was supplemented to diets with high proportion of corn silage in the forage (-2.8 g/ kg between low and high corn silage-based diets in the restricted data set) but did not decrease when the diet contained alfalfa hay. Milk trans-10 18:1 proportion increased when EL was supplemented to high corn silage-based diets. A shift in ruminal biohydrogenation pathways, from trans-11 18:1 to trans-10 18:1, probably occurred when supplementing EL with high corn silagebased diets related to a change in the activity or composition of the microbial equilibrium in the rumen. The sum of pairs 4:0 to 14:0 (FA synthesized de novo by the udder), palmitic acid, and the sum of saturated FA decreased linearly, whereas oleic acid, vaccenic acid, rumenic acid, α-linolenic acid, and the sums of mono- and polyunsaturated FA increased linearly when the daily intake of fat from EL was increased. In experimental conditions, EL supplementation increased linearly proportions of potentially human health-beneficial FA in milk (i.e., oleic acid, vaccenic acid, rumenic acid, α-linolenic acid, total polyunsaturated FA), but should be used cautiously in corn silage-based diets. [ABSTRACT FROM AUTHOR]

This study contributes to better understanding the physical controls on spatial patterns of pan-European flow signatures -- taking advantage of large open datasets for catchment classification and comparative hydrology. Similarities in 16 flow signatures and 35 catchment descriptors were explored for 35 215 catchments and 1366 river gauges across Europe. Correlation analyses and stepwise regressions were used to identify the best explanatory variables for each signature. Catchments were clustered and analyzed for similarities in flow signature values, physiography and the combination of the two. We found the following. (i) A 15 to 33% (depending on the classification used) improvement in regression model skills when combined with catchment classification versus simply using all catchments at once. (ii) Twelve out of 16 flow signatures were mainly controlled by climatic characteristics, especially those related to average and high flows. For the baseflow index, geology was more important and topography was the main control for the flashiness of flow. For most of the flow signatures, the second most important descriptor is generally land cover (mean flow, high flows, runoff coefficient, ET, variability of reversals). (iii) Using a classification and regression tree (CART), we further show that Europe can be divided into 10 classes with both similar flow signatures and physiography. The most dominant separation found was between energy-limited and moisture-limited catchments. The CART analyses also separated different explanatory variables for the same class of catchments. For example, the damped peak response for one class was explained by the presence of large water bodies for some catchments, while large flatland areas explained it for other catchments in the same class. In conclusion, we find that this type of comparative hydrology is a helpful tool for understanding hydrological variability, but is constrained by unknown human impacts on the water cycle and by relatively crude explanatory variables. [ABSTRACT FROM AUTHOR]

The versatile rhenium complex [ReCl(CO)3(bpyC≡CH)] (HC≡Cbpy = 5-ethynyl-2,2′-bipyridine) is used to generate a series of bimetallic complexes through the hydrometallation of [MHCl(CO)(BTD)(PPh3)2] (M = Ru, Os; BTD = 2,1,3-benzothiadiazole). The ruthenium complex [Ru{CH=CH-bpyReCl(CO)3}Cl(BTD)(CO)(PPh3)2] was characterised structurally. Ligand exchange reactions with bifunctional linkers bearing oxygen and sulfur donors provide access to tetra- and pentametallic complexes such as [{M{CH=CH-bpyReCl(CO)3}(CO)(PPh3)2}2(S2CNC4H8NCS2)] and Fe[C5H4CO2M{CH=CH-bpyReCl(CO)3}(CO)(PPh3)2]2. The effect of the group 8 metal on the photophysical properties of the rhenium centre was investigated using the complexes [Ru{CH=CH-bpyReCl(CO)3}Cl(BTD)(CO)(PPh3)2] and [M{CH=CH-bpyReCl(CO)3}{S2P(OEt)2}(CO)(PPh3)2] (M = Ru, Os). This revealed the quenching of the rhenium-based emission in favour of weak radiative processes based on the Ru and Os centres. The potential for exploiting this effect is illustrated by the reaction of [Ru{CH=CH-bpyReCl(CO)3}Cl(CO)(BTD)(PPh3)2] with carbon monoxide, which results in a 5-fold fluorescence enhancement in the dicarbonyl product, [Ru{CH=CH-bpyReCl(CO)3}Cl(CO)2(PPh3)2], as the quenching effect is disrupted. [ABSTRACT FROM AUTHOR]

Three-dimensional hierarchical Co3O4 nanobooks have been synthesized successfully on a large scale by calcining orthorhombic Co(CO3)0.5(OH)·0.11H2O precursors with identical morphologies. Based on the influence of reaction time and urea concentration on the nanostructures of the precursors, a stepwise splitting growth mechanism can be proposed to understand the formation of the 3D nanobooks. The 3D Co3O4 nanobooks exhibit excellent pseudocapacitive performances with specific capacitances of 590, 539, 476, 453, and 421 F/g at current densities of 0.5, 1, 2, 4, and 8 A/g, respectively. The devices can retain ca. 97.4% of the original specific capacitances after undergoing charge-discharge cycle tests 1000 times continuously at 4 A/g. [ABSTRACT FROM AUTHOR]

This article describes the general time-intensive longitudinal latent class modeling framework implemented in Mplus. For each individual a latent class variable is measured at each time point and the latent class changes across time follow a Markov process (i.e., a hidden or latent Markov model), with subject-specific transition probabilities that are estimated as random effects. Such a model for single-subject data has been referred to as the regime-switching state-space model. The latent class variable can be measured by continuous or categorical indicators, under the local independence condition, or more generally by a class-specific structural equation model or a dynamic structural equation model. We discuss the Bayesian estimation based on Markov chain Monto Carlo, which allows modeling with arbitrary long time series data and many random effects. The modeling framework is illustrated with several simulation studies. [ABSTRACT FROM PUBLISHER]

Treatment of known complex [Cp2Fe2 (μ-SEt)2(CH3CN)2](BF4) 2 (1(BF4) 2) with 2 equiv of 1,4-bis(isocyanomethyl)benzene (1,4-CNCH2C6H4CH2NC; L1) or 4,4'-diisocyanophenyl ether (4,4'-CNC6H4OC6H4NC; L2) result in the formation of two new-type diisocyanide complexes [Cp2Fe2 (μ-SEt)2(1,4-CNCH2C6H4CH2NC)2](BF4) 2 (2a(BF4) 2) or [Cp2Fe2 (μ-SEt)2(4,4'-CNC6H4OC6H4NC)2](BF4) 2(2b(BF4) 2), respectively. The new-type 24-membered ring tetranuclear iron-thiolate-aryldiisocyanide metallocyclophane complex [Cp4Fe4 (μ-SEt)4(μ-1,4-CNCH2C6H4CH2NC)2](BF4) 4 (3a(BF4) 4) has been synthesized by using a self-assembly reaction between equimolar amounts of 1(BF4) 2 and 1,4-bis(isocyanomethyl)benzene or by a stepwise route involving mixing a 1:1 molar ratio of complexes 1(BF4) 2 and 2a(BF4) 2. A similar approach was used through the application of equal molar ratio of complexes 1(BF4) 2 and 2b(BF4) 2 to give a 30-membered ring tetranuclear iron-thiolate-aryldiisocyanide metallocyclophane complex [Cp4Fe4 (μ-SEt)4(4,4'-CNC6H4OC6H4NC)2][BF4 ]4 (3b(BF4)4). The spectroscopic and electrochemical properties of four iron-sulfur core complexes were determined. [ABSTRACT FROM AUTHOR]

Stepwise transient and pulse transient methods are experimental techniques for measuring the thermal diffusivity and conductivity of solid materials. Theoretical models and experimental apparatus are presented, and the influence of the heat source capacity and the heat transfer coefficient is investigated using the experiment simulation. The specimens from low-density polyethylene (LDPE) and polymethylmethacrylate (PMMA) were measured by both methods. Coefficients of variation were better than 0.9 % for LDPE and 2.8 % for PMMA measurements. The time dependence of the temperature response to the input heat flux showed a small drop, which was caused by thermoelastic wave generated by thermal expansions of the heat source. [ABSTRACT FROM AUTHOR]

For several decades, the concerted or stepwise character of the mechanism of the 1,3-dipolar cycloaddition reaction has been one of the most debated issues in the field of organic chemistry. The significance of this problem is due to the fact that in a catalyst-free 1,3-dipolar cycloaddition, when the mechanism switches from concerted to stepwise, the stereospecificity is lost and thus unwanted stereoisomers may emerge. The first proposals about the mechanism of the 1,3-dipolar reaction were due to Huisgen (concerted model) and subsequently by Firestone (two-step diradical channel) in the 1960s. After a decade of debate, most researchers accepted the concerted model for the reaction, but during these years, researchers reported some examples of the stepwise mechanism for catalyst-free 1,3-dipolar cycloadditions. This review attempts to find a number of factors that could influence the reaction channels and switch the mechanism from concerted to stepwise, or vice versa. [ABSTRACT FROM AUTHOR]