Strategic workforce planning for the Australian Defence Force

This paper presents a mixed integer linear programming (MILP) model to aid in planning a large, hierarchically structured workforce. The workforce (eg, all Army commissioned officers) is classified by occupational group and rank and modelled in yearly intervals. Personnel and their movements are modelled as stocks and flows, subject to constraints representing employment conditions and resource limitations. The task is to estimate personnel numbers and flows so as to minimize a composite cost function. The model’s detailed fidelity to actual conditions, and hence its value in practice, clearly exceed previous efforts in the workforce planning domain. To overcome computational challenges that arose when an MILP solver was applied directly, the authors developed an iterative solution approach, which has yielded an attractive combination of solution quality and computational performance.     

6-Iodo-2-isopropyl-4H-3,1-benzoxazin-4-one as building block in heterocyclic synthesis

As a part of ongoing studies in the synthesis of a variety of heterocycles of biological importance, we report here an efficient and convenient method for the synthesis of novel compounds from 6-iodo-2-isopropyl-4H-3,1-benzoxazin-4-one 1 as building block. The reaction of benzoxazinone 1 with various reagents such as diethylmalonate, sodium azide, and phosphorus pentasulfide yielded the compounds 2–5. The behavior of benzothiazin-4-thione 5 toward formamide and hydrazine hydrate was investigated, forming the compounds 6 and 7. The reaction of quinazolinone derivative 8 with β-D-glucose pentaacetate, ethyl 2-methyl-5-((1S,2R,3R)-1,2,3,4-tetrahydroxybutyl)furan-3-carboxylate, epichlorohydrin and benzenesulphonyl chloride afforded quinazolinone derivatives 9, 10, 12, and 13 respectively. The reaction of quinazolinone derivative 10 with acetic anhydride resulted in formation of the acylated compound 11. The behavior of quinazolinylacetohydrazide derivative 14 toward carbon electrophiles^[16 El-Hashash, M. A.; El-Naggar, A. M.; El-Bordany, E. A.; Marzouk, M. I.; Nawar, T. M. S. Regioselectivity and regiospecificity of benzoxazinone (2-isopropyl4H-3,1-benzoxazinone) derivatives toward nitrogen nucleophiles and evaluation of antimicrobial activity. Synth. Commun. 2016, 46(14), 1230–1241.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]^] has been investigated by its reaction with ethyl benzoylacetate, potassium thiocyanate, and phenyl isothiocyanate, affording the quinazolinone derivatives 15, 16, and 18, respectively. Treatment of compound 16 with sodium hydroxide followed by hydrochloric acid yielded the mercapto-triazole derivative 17. The structures of the newly synthesized compounds were confirmed by elemental analysis, infrared (IR), ¹H NMR, ¹³C NMR, and mass spectra. The antimicrobial activities of some of the synthesized compounds were preliminarily evaluated.     

High‐performance liquid chromatography with diode array detection method for the simultaneous determination of seven selected phosphodiesterase‐5 inhibitors and serotonin reuptake inhibitors used as male sexual enhancers

This work presents a simple, sensitive and generic high‐performance liquid chromatography with diode array detection method for the simultaneous determination of seven drugs prescribed for the treatment of erectile dysfunction and premature ejaculation. Investigated drugs include the phosphodiesterase‐5 inhibitors: sildenafil, tadalafil, and vardenafil, in addition to the selective serotonin reuptake inhibitors: dapoxetine, duloxetine, fluoxetine, and paroxetine. The drugs were separated using a Waters C8 column (4.6 × 250 mm, 5 μm) with the mobile phase consisting of phosphate buffer pH 3, acetonitrile and methanol in the ratio 60:33:7. The flow rate was 1.2 mL/min, and quantification was based on measuring peak areas at 225 nm. Peaks were perfectly resolved with retention times 3.3, 3.9, 6.4, 7.5, 9.5, 10.7, and 13.4 min for vardenafil, sildenafil, paroxetine, duloxetine, dapoxetine, fluoxetine, and tadalafil, respectively. The developed method was validated with respect to system suitability, linearity, ranges, accuracy, precision, robustness, and limits of detection and quantification. The proposed method showed good linearity in the ranges 5–500, 2–200, 2–200, 3–300, 1.5–150, 2–200, and 2–200 μg/mL for sildenafil, tadalafil, vardenafil, dapoxetine, duloxetine fluoxetine, and paroxetine, respectively. The limits of detection were 0.18–0.38 μg/mL for the analyzed compounds. The applicability of the proposed method to real life situations was assessed through the analysis of commercial tablets, and satisfactory results were obtained.     

Minimization of Surface Energies and Ripening Outcompete Template Effects in the Surface Growth of Metal–Organic Frameworks

As well‐oriented, surface‐bound metal–organic frameworks become the centerpiece of many new applications, a profound understanding of their growth mode becomes necessary. This work shows that the currently favored model of surface templating is in fact a special case valid only for systems with a more or less cubic crystal shape, while in less symmetric systems crystal ripening and minimization of surface energies dominate the growth process.     

Dimethyl sulfoxide mediated elimination reactions in 3-aryl 2,3-dihalopropanoates: scope and mechanistic insights

Dimethyl sulfoxide (DMSO) efficiently causes the reductive elimination of 3-aryl 2,3-dibromopropanoates to cinnamates with good yield. With 3-phenyl 2,3-dihalopropanoates, debromination is the major pathway providing 3-phenylacrylate derivatives in high yields, whereas dehydrobromination is a competing pathway with thiophene derivatives. 1H NMR, 81Br NMR, and MS techniques indicated the formation of brominated-DMSO, MeBr, and HBr as byproducts in this transformation with no evidence for the formation of Br2. The dual role of DMSO as a nucleophile and bromine scavenger accounts for the products formed in this reaction.     

Crystal structure and quantum chemical calculations of (E)1-benzyl-3-((4-methoxyphenyl)imino)-5-methylindolin-2-one

The known Schiff base compound, (E)1-benzyl-3-((4-methoxyphenyl)imino)-5-methylindolin-2-one, was prepared as before by reacting 1-benzyl-5-methylindoline-2,3-dione with 4-methoxyaniline. The product was unambiguously characterized using elemental analysis, ¹H and ¹³C-NMR spectroscopy, and its new single-crystal X-ray structural analysis. Molecular orbital calculations were conducted in order to investigate the structures and relative stabilities of the (E) and (Z) isomers of 1-benzyl-3-([4 methoxyphenyl]-imino)-5-methylindolin-2-one. Specific attention was paid to the (E) isomer. The available crystallographic experimental data for the latter ensured also validation of the model structures computationally derived at the theoretical B3LYP/6-31G(d,p) level.     

Long Time Stability for Solutions of a β‐Plane Equation

We prove stability for arbitrarily long times of the zero solution for the so‐called β‐plane equation, which describes the motion of a two‐dimensional inviscid, ideal fluid under the influence of the Coriolis effect. The Coriolis force introduces a linear dispersive operator into the two‐dimensional incompressible Euler equations, thus making this problem amenable to an analysis from the point of view of nonlinear dispersive equations. The dispersive operator, , exhibits good decay, but has numerous unfavorable properties, chief among which are its anisotropy and its behavior at small frequencies.© 2016 Wiley Periodicals, Inc.     

Synthesis,Kinetics, and Equilibrium Study of Highly Sensitive Colorimetric Chemosensor for Monitoring of Copper Ions based on Benzo[f]fluorescein Dye Derivatives

The colorimetric chemosensor 2‐((3,5‐dichloro‐2‐hydroxybenzylidene)amino)‐3′,6′‐dihydroxy‐6‐methyl‐4‐(p‐tolyl)spiro[benzo[f]isoindole‐1,9′‐xanthen]‐3(2H)‐one ( BFFSH ) derived from benzo[f]fluorescein dye was synthesized. NMR and IR spectroscopy as well as mass spectrometry were used to confirm the compound. BFFSH shows potential application for detecting metal ions in aqueous solution. It displays a colorimetric selectivity and sensitivity towards the aqueous solution of Cu²⁺ ions with a detection limit in the nano‐molar range (1.69 nM). In addition, the application of BFFSH was extended for the detection of Cu²⁺ ions in real water samples (tap and synthetic water) with a high recovery percentage. Additionally, the association constant (K_a) of BFFSH , which binds with Cu²⁺ ions based on 2:1 stoichiometry was calculated.     

Application of the intramolecular Yamamoto vinylogous aldol reaction to the synthesis of macrolides

An intramolecular version of the Yamamoto vinylogous aldol reaction, a method that employs the bulky Lewis acid ATPH to control the site of aldolization, is described. This macrocyclization process is effective for the construction of 10-, 12-, and 14-membered macrolides. The yields are high (70-90%), and the reaction can proceed with excellent remote stereocontrol (dr > or = 20:1) with chiral substrates.