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With technological advancement, the use of drones in delivery systems has become increasingly feasible. Many companies have developed rotary‐wing drone (RWD) technologies for parcel delivery. At present, the limited endurance is the main disadvantage of RWD delivery. The energy consumption of RWDs must be carefully managed, and it is necessary to develop an effective energy‐consumption model to support RWD flight planning. Because the interaction between the forces on the RWD and its flying environment is very complex, it is challenging to estimate accurately the RWD energy consumption. This study summarizes several energy‐consumption models proposed in the literature, then we develop an RWD energy‐consumption model (called the integrated model) based on analyzing the dynamic equilibrium of forces and power consumption in flight phases (including climb, descent, hover, and horizontal flight). Computational experiments involving several commercial RWDs indicate that the integrated model is more effective than several models in the literature. In the case where an RWD completed one flight segment, on average, 87.63% of the battery capacity was consumed in the horizontal flight phase. We also analyzed the effects of the total mass and horizontal airspeed on the RWD endurance and found that a larger mass corresponded to shorter endurance, and in the experimental range of the horizontal airspeed, a higher horizontal airspeed corresponded to longer endurance. Moreover, the total mass affected the RWD endurance more significantly than the horizontal airspeed. [ABSTRACT FROM AUTHOR]

Hypochlorite is a kind of endogenously produced reactive oxygen species (ROS) in the human immune system and plays a crucial role in many pathophysiological processes. In this work a novel fluorescent probe derived from 6‐methylthio coumarin was designed and synthesised for detection of hypochlorite in acetonitrile/phosphate‐buffered saline (MeCN/PBS) (1:1, v/v, pH 7.4) medium. The probe displayed high specificity toward hypochlorite over other ROS analytes, rapid response to hypochlorite within 30 s, and a broad applicable range of pH 3–8. The detection limit was calculated to be 1.48 μM. Application of this probe for in vitro Hecat cell imaging to detect hypochlorite ions was confirmed. A sensing mechanism based on thioether to sulfoxide oxidation by hypochlorite was proposed and demonstrated. The study presented an effective approach for construction of highly efficient hypochlorite chemosensors from hydrophilic methylthio‐substituted coumarins considering their facile access. [ABSTRACT FROM AUTHOR]

It is particularly important to develop effective and specific detection methods for harmful metal ions such as the silver ion (Ag+) and mercury ion (Hg2+). In this article, a new near‐infrared (NIR) fluorescent probe (N‐FP) based on intramolecular charge transfer (ICT) effect was designed and synthesised, which exhibited the characteristics of large Stokes shift (163 nm) and excellent stability. Addition of Ag+ or Hg2+ to the N‐FP solution in ethanol/water (9:1, v/v) caused remarkable enhancement of fluorescence emission at 661 nm, bathochromic shift of ultraviolet‐visible absorption wavelength, and colour change from orange to red or purple. While adding other metal ions including Li+, Na+, K+, Ag+, Cu2+, Fe2+, Zn2+, Co2+, Ni2+, Mn2+, Sr2+, Ca2+, Mg2+, Al3+, Cr3+ and Fe3+ did not bring about substantial spectral and colour change. The detection limit of the N‐FP for Ag+ and Hg2+ was calculated to be 1.1 and 0.72 μM, respectively. The N‐FP could be used to recognise Ag+ and Hg2+ in a wide pH range of 1–10. The sensing mechanism was proposed and demonstrated by proton nuclear magnetic resonance (1H‐NMR), high‐performance liquid chromatography (HPLC) and mass spectrometry (MS) measurements [ABSTRACT FROM AUTHOR]

Considering the important realistic benefits of drones combined with trucks for last‐mile parcel deliveries, we define the truck–drone routing problem with time windows (TDRP‐TW). The TDRP‐TW has the characteristics of time windows, synchronization en route, direct delivery, multiple trucks, and multiple drones carried by each truck. Customers covered by truck routes can be used as drone launch/retrieval locations, which are called satellites in this study. The synchronization en route enables drones to launch from trucks to return to paired trucks at nodes other than departure sites if necessary. We present an effective branch‐price‐and‐cut algorithm, in which a concept named candidate forward‐satellite (CFS) is introduced to manage the labeling challenge caused by the synchronization en route. In addition, the branch‐price‐and‐cut algorithm is combined with an adaptive large neighborhood search to obtain approximation solutions for large‐scale instances. In the computational experiments, instances with up to 50 customers are solved to optimality, and approximation solutions of large‐scale instances with 100 customers are presented. [ABSTRACT FROM AUTHOR]

Truck–drone technology that enables drones to launch from or land on a moving truck without the need for the truck to stop is the focus of this study. We define the truck and drone routing problem with synchronization on arcs (TDRP‐SA). The TDRP‐SA is characterized by synchronization on arcs, time windows, classified customers, direct delivery, multiple trucks, and multiple drones carried by each truck. The TDRP‐SA involves synchronization on arcs to permit trucks to dispatch and retrieve drones at suitable moving‐LRLs (drone launch/retrieval locations) on arcs of truck routes. A moving‐LRL is essentially a drone launch/retrieval location with a moving truck, and the drone launch/retrieval operations do not need special parking for the trucks. We develop a mixed integer nonlinear programming model to address the TDRP‐SA. We propose a mathematical analysis method to locate moving‐LRLs and to estimate the drone's arrival time at the customers. We develop boundary models through introducing linear piecewise functions to locate moving‐LRLs. We provide an adaptive large neighborhood search (ALNS) heuristic. Through computational experiments, the effectiveness of the boundary models, the TDRP‐SA model and ALNS‐based heuristic are evaluated. [ABSTRACT FROM AUTHOR]

A fluorescent probe derived from cyanine‐rhodanine conjugate was developed for dual detection of mercury (Hg2+) ion and pH. Addition of Hg2+ ion to the weakly fluorescent probe solution in dimethyl sulphoxide/water (DMSO/H2O, 7:3, v/v) induced discernible colour change and fluorescence enhancement while other metal cations including Li+, Na+, K+, Ag+, Cu2+, Fe2+, Zn2+, Co2+, Ni2+, Mn2+, Sr2+, Ca2+, Mg2+, Al3+, Cr3+ and Fe3+ did not cause obvious change in colour and fluorescence emission. The detection limit of the probe toward Hg2+ ion is 1.61 × 10−7 M. The probe also exhibited remarkable pH‐responsive effect. It acts as a dual chromogenic and spectroscopic probe for determining different pH scales over a wide range of pH 1.0–14.0: bright yellow with maximum wavelength (λmax) 416 nm for pH 1.0–2.0, orange with λmax 470 nm for pH 3.0–9.0, and pale yellow with λmax below 400 nm for pH 10.0–14.0. Plausible sensing mechanisms of the probe toward Hg2+ ion and pH have been proposed. [ABSTRACT FROM AUTHOR]

The effects of small‐scale topographic perturbations on precipitation forecasts are investigated using the China Meteorological Administration's Convection‐Permitting Ensemble Prediction System. Southern China is chosen as the study domain because complex terrain is located there and heavy rainfall frequently occurs. The investigation comprises seven cases including strong and weak forcings on the synoptic scale in terms of convective adjustment time‐scale and synoptic conditions. To construct the topographic perturbation scheme, the standard deviations of small‐scale topographic heights and random fields were first introduced, and sensitivity runs with different topographic perturbation magnitudes were performed at a 3‐km horizontal grid spacing. The results indicate that the model runs with a single topographic perturbation show small changes in precipitation forecasts on strong‐forcing cases and more important impacts for weak‐forcing events, but the effect is also restricted to the control forecast skills. In addition, the topographic perturbation impacts the precipitation forecasts through dynamic processes, and the impact areas are mainly found at locations with rainstorms and heavy rainstorms in the observations. Moreover, the precipitation forecasts react sensitively to the topographic perturbation magnitude, with a larger topographic perturbation magnitude leading to larger amplitudes and spatial gain of precipitation ensemble spread, as well as a better Brier score. However, the selection of the perturbation magnitude is also influenced by the standard deviations of the small‐scale topographic heights. [ABSTRACT FROM AUTHOR]

A new coumarin derivative containing both imine bond and amide moiety was synthesised. It was used as a reaction‐based pH probe and was sensitive to pH changes in the intervals 1.50–4.10 and 10.20–12.86. In the pH range 1.50–4.10, the ultraviolet‐visible (UV‒vis) absorption band of the probe gradually shifted from 353 nm to 340 nm with decrease in the pH value. The colour changed from pale yellow fluorescence at pH 4.10 to blue fluorescence at pH 1.50. Meanwhile the fluorescence emission band at 501 nm gradually shifted to 560 nm accompanying a gradual enhancing in the emission intensity. This pH response is caused by the hydrolysis of the imine bond in the probe under acidic conditions (pH 1.50–4.10). The colourless probe solution turned yellow at pH range 10.20–12.86. Bathochromic shift of the fluorescence band from 501 nm gradually to 550 nm was observed with the increase of pH value from 10.20 to 12.86 accompanying a gradual enhancement of the fluorescence emission intensity, indicating that the new compound serves as a fluorescent pH probe at pH range 10.20–12.86 through a deprotonation process. Under strongly alkaline conditions with pH larger than 12.86, hydrolysis of the lactone structure in the probe occurred to produce non‐fluorescent species. [ABSTRACT FROM AUTHOR]

A coumarin‐based fluorescent probe containing both acrylate moiety and an allyl substituent was developed for distinguishing cysteine from homocysteine. The maximum absorption wavelength of the probe showed a bathochromic shift upon addition of cysteine and the colour changed from colourless to yellow. The maximum fluorescence emission at 462 nm of the probe was dramatically enhanced upon addition of cysteine in aqueous solution. In HEPES buffer (pH = 7.4, EtOH/H2O = 9:1, v/v), both of the fluorescence emission bands of the probe at ca. 390 and 462 nm were intensely enhanced upon the addition of cysteine, while other amino acids, namely, homocysteine, asparaginic acid, methionine, glycine, phenylalaninase, valine, tryptophan, serine, glutamic acid and glutathione, did not cause a remarkable change. The probe can be used for selectively colorimetric and ratiometric fluorescent detection of cysteine over homocysteine and other common amino acids in both organic media and aqueous solution. The concentration of cysteine can be estimated by titration of the probe in aqueous solution, and the detection limit of the probe towards cysteine was 2 μmol/L. [ABSTRACT FROM AUTHOR]

Software Outsourcing Partnership (SOP) is considered as a type of risk and reward sharing relationship between a client organisation, in the developed countries, and its overseas vendor organisation. Regardless of numerous benefits, the development of SOP still remnants in its infancy stage due to several interactive barriers. Some studies have been conducted to examine the barriers to SOP formation. However, no attempt has been reported so far to explore the multifaceted interrelationships amongst them. To bridge the gap, this study implements Interpretive Structural Model (ISM) approach to reconnoitre the interrelationships amongst the barriers in the context of SOP formation. The objective of this research paper is to develop a framework for modelling structural association amongst the barriers. To achieve the objective, we used a hybrid methodology based on systematic literature review (SLR), empirical survey, and ISM. Firstly, via SLR study, we identified 27 barriers to SOP formation. Secondly, to empirically explore the interrelationships amongst the identified barriers, a questionnaire survey was performed with 50 experts from a total of 20 different countries. Further, interrelationships amongst the barriers were identified using ISM via panel review, and their classifications were carried out via Cross‐Impact Matrix Multiplication Applied to the Classification Approach. [ABSTRACT FROM AUTHOR]

Software Outsourcing Partnership (SOP) is considered as a kind of risk and reward sharing client‐vendor relationship. Generally, a fruitful outsourcing association might be converted to an outsourcing partnership. The objective of this research is to identify and analyse barriers that are hurdles to vendors in renewing or promoting their ongoing client‐vendor relationship to outsourcing partnership. A questionnaire survey based on the findings of Systematic Literature Review (SLR) was performed with 50 experts. The study identifies five critical barriers such as "insufficient quality of technical capability," "poor infrastructure," "poor quality of service," "communication gap and poor coordination," and "relational risk." The results indicate that barriers' insufficient quality of technical capability, poor infrastructure, and poor quality of service were common in four types of experts while insufficient quality of technical capability is common in three levels of experts. Furthermore, barriers were classified based on their criticality from client‐vendor perspective. The results of Spearman correlation test (rs = 0.714 and ρ = 0.000) confirmed that the participant strongly agrees with the outcomes of the SLR. The results suggest that for successful renewal or promotion of their existing outsourcing association, vendor organizations should address all the identified barriers in general and the most common barriers in particular. [ABSTRACT FROM AUTHOR]

A fluorescent probe based on a simple coumarin derivative could recognise mercury ions (Hg(ii)) and thiols selectively in aqueous solution. The addition of Hg(ii) induced a blue shift of the fluorescence emission band of the probe while the fluorescence was almost quenched by the addition of p‐toluenethiol or cysteine (Cys). The detection limit of the probe towards Hg(ii) and Cys was 8 µmol/L. The probe could be used for the detection of Hg(ii) and thiols by the naked eye under ultraviolet light irradiation. [ABSTRACT FROM AUTHOR]

Five new 7-alkyloxy-4-trifluoromethylcoumarin fluorescent dyes were synthesised using the Pechmann and Williamson etherification reactions. The structures of these coumarin dyes were characterised by Fourier Transform-infrared, proton and carbon nuclear magnetic resonance and mass spectra. One of the new coumarin compounds, 7-isopropyloxy-4-trifluoromethylcoumarin, was microencapsulated with melamine-formaldehyde as the shell material by in situ polymerisation. The microcapsules were characterised in terms of Fourier Transform-infrared spectrum, particle size distribution and scanning electron microscopy morphology. The cotton fabric finished with the microencapsulated coumarin dye showed strong fluorescence under ultraviolet light. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor-2 (FGF2) is produced as high molecular weight isoforms (HMW) and a low molecular weight isoform (LMW) by means of alternative usage of translation start sites in a single Fgf2 mRNA. Although the physiological function of FGF2 and FGF2 LMW has been investigated in myocardial capillarogenesis during normal cardiac growth, the role of FGF2 HMW has not been determined. Here, we report the generation of FGF2 HMW-deficient mice in which FGF2 HMW isoforms are ablated by the Tag-and-Exchange gene targeting technique. These mice are normal and fertile with normal fecundity, and have a normal life span. Histological, immunohistochemical, and morphometric analyses indicate normal myocardial architecture, blood vessel, and cardiac capillary density in young adult FGF2 HMW-deficient mice. These mice along with the FGF2- and FGF2 LMW-deficient mice that we have generated previously will be very useful for elucidating the differential functions of FGF2 isoforms in pathophysiology of cardiovascular diseases. Developmental Dynamics 238:351-357, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Provides a comprehensive description of the permineralized, vessel-bearing gigantopterid stems and establish them as a taxon, Vasovinea tianii Li et Taylor gen. et sp. nov. Systematics and description; Cortical histology; Description of the vascular system.

The sensor can be used in the presence of common metal cations and anions without interference. [ABSTRACT FROM AUTHOR]

In the title salt adduct, C(17)H(21)ClN(2) (2+)·2C(2)Cl(3)O(2) (-)·C(2)HCl(3)O(2), the Cl atom of the dication is disordered over two positions in a 0.915 (3):0.085 (3) ratio. The Cl atoms in the trichloroacetate anions and trichloroacetic acid molecule are also disordered, with refined site-occupation factors of 0.59 (3):0.41 (3), 0.503 (12):0.417 (12) and 0.653 (12):0.347 (12). The piperazine ring adopts a chair conformation, with puckering parameters Q(T) = 0.587 (3) Å, θ = 2.6 (2) and Φ 334 (6)°. In the crystal, neighbouring mol-ecules are linked by N-H⋯O, O-H⋯O, N-H⋯Cl, C-H⋯O and C-H⋯Cl hydrogen bonds, forming a three-dimensional network.

The asymmetric unit of the title compound, C(17)H(20)ClN(2) (+)·C(6)H(2)N(3)O(7) (-)·H(2)O, contains a piperazin-1-ium cation, a picrate anion and one solvent water mol-ecule. The piperazene ring is protonated at one N atom and adopts a highly distorted chair conformation with the chloro-pheny(phen-yl)methyl substituent on the second N atom in an equatorial position. The crystal structure is stabilized by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds.

In the title salt {systematic name: 4-diphenyl-methyl-1-[(E)-3-phenyl-prop-2-en-1-yl]piperazin-1-ium 2,4,6-trinitro-pheno-late), C(26)H(29)N(2) (+)·C(6)H(2)N(3)O(7) (-), the cinnarizinium cation is protonated at the piperazine N atom connected to the styrenylmethyl group; the piperazine ring adopts a distorted chair conformaiton. In the crystal, bifurcated N-H⋯(O,O) hydrogen bonds link the components into two-ion aggregates.

In the structure of the title compound, C(7)H(10)OS(4)Si, the carbonyl O atom lies in the plane of the five-membered dithiole ring with a deviation of only 0.022 (2) Å. The seven-membered ring adopts a chair conformation. The crystal packing is stabilized by S⋯O [3.096 (4) Å] and S⋯S [3.620 (4) Å] contacts, together with C-H⋯S inter-actions.

The title compound, C(21)H(20)O(2)S(2), forms a propeller-shaped structure with the tetra-hedral C atom as the central hub and meth-oxy-benzene and phenyl residues as radiating blades. Short C-H⋯π contacts are observed.

The title compound, C(21)H(19)ClF(3)N(3)O(2), has a structure related to other coumarin derivatives that have been used as fluorescent probes of metal ions. The dihedral angle between the coumarin ring system and the chlorobenzene ring is 42.99 (9)°. Intra-molecular hydrogen bonding occurs via N-H⋯O and N-H⋯Cl inter-actions, generating S(7) and S(5) rings, respectively. The crystal packing is stabilized by weak C-H⋯O hydrogen bonds.

IN THE TITLE COMPOUND [SYSTEMATIC NAME: 3,3'-dimethoxy-2,2'-(ethane-1,2-diyldioxy)dibenzaldehyde], C(18)H(18)O(6), prepared from 1,2-dibromo-ethane and ortho-vanillin in the presence of sodium carbonate, the two vanillin units are linked via a CH(2)-CH(2) bridge. The two benzene rings are inclined at a dihedral angle of 41.6 (5)°.

The mol-ecule of the title compound, C(16)H(11)BrO(3), is essentially planar with a maximum deviation of 0.178 (4) Å and the configuration of the keto group with respect to the olefinic double bond is typically s-cis. In the crystal structure, inter-molecular Br⋯O inter-actions [3.187 (3)Å] give rise to chains parallel to the b axis. Adjacent chains are further linked along the a axis by C-H⋯π inter-actions. The crystal studied was a racemic twin with a 0.595 (13):0.405 (13) ratio.

The title compound, C(11)H(14)F(2)O(4), is a γ,γ-gem-difluorinated α,β-unsaturated δ-lactone. The dioxolane five-membered ring and the lactone ring adopt half-chair conformations. There are two inter-molecular C-H⋯O inter-actions involving the carbonyl group as an acceptor which stabilize the crystal structure.

In the title compound, C(15)H(10)BrClO, the mol-ecule adopts an E configuration with respect to the C=C double bond and the dihedral angle between the aromatic ring planes is 3.98 (16)°. In the crystal, inversion dimers linked by pairs of C-H⋯O bonds are seen and weak π-π stacking [centroid-centroid separation = 3.8776 (19) Å] may further consolidate the structure. The crystal studied was a non-merohedral twin with a ratio of the twin components of 0.9093 (13):0.0907 (13). The twin operation is a twofold rotation around c*.

In the title compound, C(15)H(12)Br(2)N(2)O(2), the mol-ecule adopts an E conformation about the C=N double bond and a transoid conformation about the central N-N bond, with a C(=O)-N-N-C(H) dihedral angle of 169.4 (4)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, leading to C(4) chains. The packing also features slipped π-π stacking inter-actions, with a centroid-centroid separation of 3.838 (3) Å and a slippage of 1.19 Å.

The title compound, C(24)H(22)O(4)S, was prepared by reaction between (2E)-3-(6-meth-oxy-2-naphth-yl)-1-(2-thien-yl)prop-2-en-1-one and ethyl acetoacetate. In the crystal, the cyclo-hexenone ring shows a distorted half-chair conformation. The length of the double bond in the cyclohexenone ring [1.343 (4) Å] is normal.

In the title compound, C(27)H(26)O(4), the dihedral angle between the naphthalene ring system and the benzene ring is 73.10 (5)°. In the crystal, a weak C-H⋯O inter-action occurs. Two C-H groups of the cyclo-hexene ring are disordered over two sets of sites in a 0.796 (5):0.204 (5) ratio, which corresponds to partial overlap of the two enanti-omeric mol-ecules.

The title compound, C(8)H(2)Br(4)S(2), was prepared by bromination of 2,2'-bithio-phene with bromine. The mol-ecule is located on a crystallographic twofold rotation axis, thereby imposing equal geometry of the two thio-phene rings. Each five-membered ring is planar [maximum deviation 0.011 (9) Å] and the dihedral angle between the planes through the rings is 47.2 (4)°. The mol-ecules are arranged to minimize intramolecular contacts between the 3-3' and 5-5'-bromine atoms.

The title compound {systematic name: [1-(carboxy-meth-yl)cyclo-hexyl]methanaminium 2,4,6-trinitro-phenolate}, C(9)H(18)NO(2) (+)·C(6)H(2)N(3)O(7) (-), was synthesized from picric acid and gabapentin. The crystal packing is stabilized by intra-molecular N-H⋯O=N and N-H⋯O-Ph hydrogen bonds. An O-H⋯O inter-action is also present.

The title compound, C(13)H(19)N(2)O(2) (+)·C(6)H(2)N(3)O(7) (-), is a salt obtained by cocrystallization of 4-[(4-methyl-piperazin-1-yl)meth-yl]benzoic acid and picric acid. The cations adopt an 'L-shaped' conformation and are linked into chains along [010] by O-H⋯N hydrogen bonds. The NH group of each piperazinium ring forms a hydrogen bond to the phenolate O atom of a picrate anion, and the picrate anions form face-to-face contacts with an inter-planar separation of 3.023 (1) Å.

In the title compound, C(16)H(11)BrO(3), the mol-ecules adopt an E configuration with respect to the C=C double bond of the propenone unit. The 13 non-H atoms of the benzodioxole and propenone units are approximately coplanar (r.m.s. deviation = 0.027 Å) and the bromo-benzene ring plane forms a dihedral angle of 10.8 (1)° to this plane. The structure is layered, with the mol-ecules forming a herring-bone arrangement within each layer.

The title compound, C(16)H(13)BrO, was synthesized from the reaction of 3-bromo-benzaldehyde and 4-methyl-acetophenone in the presence of KOH. The mol-ecule adopts an E configuration with respect to the C=C double bond of the propenone unit. The dihedral angle formed by the aromatic rings is 46.91 (14)°. The crystal structure is stabilized by Br⋯Br inter-actions [3.4549 (11) Å].

In the title compound, C(11)H(18)O(5)S(2), the six- and five-membered rings adopt a chair and an approximately planar conformation, respectively.

In the title compound, C(21)H(24)O(2), rings B, C and D adopt half-chair, distorted half-chair and envelope conformations, respectively. In the crystal structure, there is an inter-molecular O-H⋯O hydrogen bond. The mol-ecules are arranged in a head-to-tail fashion, with the meth-oxy and hydr-oxy groups forming a two-dimensional hydrogen-bond network.