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The primary aim of this study was to examine the impact of xylooligosaccharide (XOS) in rice protein concentrate (RPC) based diets on the growth performance, body composition, digestive enzymes, intestinal morphology and blood biochemistry of Labeo rohita fingerlings. Four different XOS levels (0%, 0.5%, 1% and 2%) were used at each RPC (75% and 100%) level. Twenty‐five fish per tank with an average initial weight of 25 ± 0.05 g were randomly assigned (Randomised complete block design) to each of the 8 groups in triplicate aquaria (36 × 16 × 12″) and then fed with respective diets @ 3% body weight for 90 days. The results showed significant improvements in growth performance, such as increased weight gain %, specific growth rate, and protein efficiency ratio and improved feed conversion ratio in 1% XOS supplemented diet at 75% RPC. A significant decrease in serum alkaline phosphatase activity (ALP) and plasma melanodialdehyde (MDA) were observed at 1% XOS level in 75% RPC based diets, respectively. Meanwhile, the lowest total cholesterol and highest lysozyme activity were observed in 1% XOS supplemented diet at 75% RPC levels. Moreover, the serum (alanine aminotransferase and aspartate transaminase) and plasma (superoxide dismutase, triglyceride, high density and low density lipoprotein) activities showed nonsignificant effects among the treatments. Furthermore, the digestive enzymes (protease & lipase) and intestinal morphology were significantly influenced at 1% XOS in the 75% RPC‐based diet. Polynomial regression analysis showed that 1.25% XOS is the optimum requirement for the growth of rohu fingerlings when fed at 75% RPC based diets. Overall, it was concluded that the 75% RPC diet was efficiently replaced by fishmeal along with 1% XOS addition in L. rohita fingerlings without any negative effect on growth performance and intestinal health. [ABSTRACT FROM AUTHOR]

The current study was performed to investigate the impact of different temperatures and protein levels on the growth performance, proximate composition and digestive and hepatic enzyme activities of Labeo rohita fingerlings. For this purpose, healthy fingerlings (average initial weight of 6.40 ± 0.02 g) were acclimatized for 15 days, then reared at three temperatures (25°C, 30°C and 35°C) and fed three levels of crude protein (25%, 30% and 35% crude protein (CP)) twice daily until satiation for 60 days. The results of the study revealed that the highest growth performance was observed in fish fed 35% protein and reared at 30°C. Similarly, fish reared at 35°C and 25°C water temperature showed comparatively better growth performance in fish fed with 35% protein. Furthermore, a significant enhancement in feed intake was observed with increasing culture temperature and increasing CP levels, but at 25°C, increasing CP levels significantly decreased the feed intake. Sligh variations were also observed in proximate composition in terms of moisture, CP, crude fat (CF) and ash contents in fish fed with different CP levels and reared at different temperatures. The hepatosomatic index and viscerosomatic index decreased significantly with increasing levels of protein and temperature. Amylase activities were significantly reduced with increasing culture temperature at each protein level. Increasing culture temperature did not affected the lipase activities. However, lipase activities were enhanced with increasing CP levels at 25°C and activities decreased with increasing CP levels at 30–35°C. Protease activity was enhanced with increasing temperature and CP levels. Significant increases were also observed in serum total proteins and liver functioning enzymes such as alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase in response to increased temperature, and protein had a reciprocal effect. It is concluded that increasing the CP levels increased the growth performance independent of temperature. However, similar growth performance at 30 CP (30°C) and 35 CP (35°C) indicates that L. rohita requires more protein at higher temperature for optimum growth. [ABSTRACT FROM AUTHOR]

Variable properties like thermal conductivity and variable thickness of the disk are analyzed for the Jeffery nanofluid and gyrotactic microorganisms in rotating system taking into account the Cattaneo‐Christov heat flux, velocity slip and thermal radiation effects. Zero mass flux is assumed at the disk surface for the better and high accuracy of the out‐turn. The governing equations of the problem are transformed into nonlinear ordinary differential equations by introducing the appropriate similarity transformations which are solved analytically by the homotopy analysis method. The effects of all the parameters are given in detail through the graphs. [ABSTRACT FROM AUTHOR]

Natural herbs are excellent alternatives to synthetic compounds to enhance the growth performance and health status of fish. This study was conducted to evaluate the efficacy of black cardamom (Amomum subulatum) extract (BCE) as an herbal supplement in improving the growth, antioxidant status, haematology, and serum biochemistry of Catla catla. The acclimatized fish (N = 900; average initial weight = 14.44 ± 0.33 g) were allocated into five groups (60 fish/group in triplicate) in hapas (4 × 2 × 2.5 ft) and provided with feed containing 0 (control), 0.5, 1, 2 and 4 g/kg BCE for 90 days before being subjected to 8 days of crowding stress. After 90 days, significantly higher feed utilization and growth were observed in all BCE‐fed treatments compared to the control; however, the maximum values of these parameters were noted in the 2 g/kg BCE‐fed treatment. Moreover, the BCE‐fed groups exhibited a significant increase in antioxidant indices (glutathione peroxidase, superoxide dismutase and catalase), with a significant reduction in malondialdehyde levels, indicating a higher antioxidant capacity compared to the control. Significant improvements in haematological parameters, such as an increase in haematocrit, haemoglobin and red blood cells and a decrease in white blood cells, were observed in BCE‐fed treatments compared to the control. Furthermore, BCE‐fed groups showed a significant decrease in serum glucose, cortisol and triglycerides, while total protein, globulin and albumin levels were significantly higher compared with the control. During the feeding trial of 90 days, no mortality was observed; however, the lowest cumulative mortality was noted in the 2 g/kg BCE group after crowding stress of 8 days. In conclusion, the use of BCE in feed can enhance the growth performance, antioxidant status, haematology, and serum biochemistry of C. catla and improve the resistance against crowding stress. The optimum levels of BCE for C. catla were estimated based on weight gain % (1.78 g/kg; R2 = 0.97), feed conversion ratio (1.65 g/kg; R2 = 0.98), MDA content (1.66 g/kg; R2 = 0.93) and serum lysozyme activity (1.72 g/kg; R2 = 1) using broken‐line regression analysis. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the optimal dietary phosphorus (P) requirement and its effects on growth performance, body composition, mineralization and alkaline phosphate (ALP) activity in silver carp (Hypophthalmichthys molitrix). A total of 360 fish with an average initial weight of 7.0 ± 0.15 g were divided into 18 tanks (70 L capacity each) with a stocking density of 20 fish per tank in triplicate. The fish were fed diets containing six levels of P (3.3, 4.4, 5.5, 6.5, 7.5 and 8.6 g/kg) up to satiation for 90 days twice daily at 09:00 and 16:00. The results showed that fish fed diets containing 6.5 and 7.5 g/kg dietary P had significantly higher (p < 0.05) growth performance in terms of final weight gain, average weight gain (AWG), weight gain% (WG%), protein efficiency ratio (PER) and specific growth rate (SGR) than fish fed other diets. The best value of the feed conversion ratio (FCR) was observed in fish fed the 6.5 g/kg P diet, which was not significantly different from the 7.5 g/kg P diet. Increasing P supplementation above 6.5 g/kg significantly reduced (p < 0.05) the feed intake of silver carp. Whole‐body composition analysis indicated that increasing P levels resulted in a decrease (p < 0.05) in crude fat (CF) and an increase (p < 0.05) in crude ash (CA) content, while crude protein (CP) and moisture content remained unaffected (p > 0.05). Fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Ca content in the whole body, bones and scales compared to those fed diets containing ≤5.5 g/kg P. A similar trend was observed for P and Mg contents in the whole body, bones and scales. The Zn content tended to decrease (p < 0.05) with increasing P supplementation in the whole body and bones, but fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Zn content compared to fish fed diets containing ≤5.5 g/kg P. The Ca/P ratio was significantly affected by P supplementation. Fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Ca and P contents in the serum than fish fed other diets. ALP activity increased (p < 0.05) with increasing P levels up to 6.5 g/kg P and decreased (p < 0.05) thereafter. In conclusion, supplementing P up to 6.35 g/kg is recommended for the optimal growth of silver carp. [ABSTRACT FROM AUTHOR]

The drop in temperature during the winter months can lead to a decrease in growth, induce metabolic stress, and increase mortality incidences. The present study evaluated the potential of functional feed additives in mitigating the negative impacts of winter‐rearing conditions in striped catfish (Pangasianodon hypophthalmus). Four test diets were evaluated over a twelve‐week feed trial: (1) zinc‐acetate (Zn‐acetate), (2) selenomethionine (Se‐Met), (3) β‐glucan, and (4) control with no added feed additive. The survival rate in the β‐glucan (95.00%) and Zn‐acetate (93.30%) dietary groups was higher than the control (78.30%) and Se‐Met (85.00%). Fish fed with the β‐glucan had the highest weight gain (20.75% increase), specific growth rate (13.75% increase), and lower feed conversion ratio (9.64 % decrease). However, feed additives did not influence the fatty acid profiles or whole‐body proximate composition. Although, Zn‐acetate and Se‐Met had higher body ash content. Serum cortisol and glucose levels were lower in β‐glucan and Zn‐acetate than in other treatment groups. All feed additives resulted in higher superoxide dismutase, glutathione peroxidase, and catalase activity in the liver and muscle. This study found that β‐glucan and zinc‐acetate can improve cold stress resistance and offer a sustainable strategy for catfish rearing over winter. [ABSTRACT FROM AUTHOR]

The effects of magnetic dipole, porosity and heat transfer on the flow of ferromagnetic Walter‐B fluid past a curved stretching sheet is investigated with the gyrotactic microorganisms motion and cubic autocatalysis chemical reactions. The momentum, energy, homogeneous–heterogeneous chemical reactions and gyrotactic microorganisms motion equations, form the problem's governing equations, which are transformed into non‐linear ordinary differential equations via similarity transformations and are solved using an efficient and strong technique namely homotopy analysis method. The effects of the parameters under consideration on dimensionless velocity, temperature, homogeneous–heterogeneous chemical reaction, and motile microorganisms are graphically depicted and discussed in detail. Velocity decreases with the increasing values of curvature parameter while the magnetic dipole effect and Curie temperature parameter increase the heat transfer. The homogeneous chemical reaction and the motile density of microorganisms are enhanced with the rising values of elasticity and ferromagnetic interaction parameters. [ABSTRACT FROM AUTHOR]

A study was conducted to determine the artificial breeding response, embryonic and larval development of giant snakehead, Channa marulius, with the application of various dosages of stimulatory hormones: Suprefact® (LHRH) agonist and Ovaprim® (GnRH + dopamine inhibitor). First and second hormonal dosages of Suprefact® (diluted) and Ovaprim® (0.3, 0.4, and 0.5 ml for male and 0.8, 0.9, and 1.0 ml for females per kilogram body weight) were used. There were three treatments T1, T2, and T3 and each treatment had three replicates. Male fish were treated with T1 (0.3), T2 (0.4), T3 (0.5) ml kg−1 of body weight while female fish with T1 (0.8), T2 (0.9), T3 (1.0) ml kg−1 of body weight. The results showed that fish stimulated with T3 (1.0) obtained better fecundity rate (2951.7) followed by T2 (0.4) (2678.3), while the lowest fecundity (466.7) was recorded in T1. The numerically higher values of gonado‐somatic index (males and females) and fertilization rate appeared in T2. The highest survival rate (97.1%) was found in T3 followed by T2 (97.0%), while the lowest (32.2%) in T1. In conclusion, the application of Suprefact® and Ovaprim® at 0.4 and 0.5 ml kg−1 body weight for male and 0.9 and 1.0 ml kg−1 for female fish successfully stimulated snakehead fish induced breeding. [ABSTRACT FROM AUTHOR]

The massive growth of biomedical knowledge in computable formats poses a challenge for organizations as they consider mobilizing artifacts to be findable, accessible, interoperable, reusable, and trustable. Formed in 2016, the Mobilizing Computable Biomedical Knowledge (MCBK) community is taking action to ensure that health organizations have the infrastructure in place to access and apply computable knowledge; to develop national policies and standards that require all data to be discoverable and available for safe and fair use; and to promote the widespread adoption and implementation of health knowledge in support of healthcare, biomedical research, public health, and education. This report summarizes the main outcomes of the Fifth Annual MCBK meeting, also considered the first manifestly global MCBK meeting, which was held virtually July 12 to 13, 2022. Over 200 participants from diverse domains around the world joined this meeting to frame and address important dimensions for mobilizing CBK. [ABSTRACT FROM AUTHOR]

Entropy generation in unsteady magneto‐bioconvection Casson nanofluid flow with gyrotactic microorganisms in the presence of Cattaneo–Christov heat and mass flux theory is analyzed. Buongiorno nanofluid model is followed taken into account the influences of viscous dissipation, Brownian motion, and thermophoresis. Mathematica is used to compute the transformed equations through homotopy analysis method (HAM) resulting from the implementation of similarity transformations on governing equations and boundary conditions. The effects of pertinent parameters on different profiles are shown in graphs and discussed in detail. [ABSTRACT FROM AUTHOR]

Metasurfaces are planar or 2D forms of metamaterials made up of arrays of antennas with a subwavelength thickness. They have been rapidly developed in the recent years due to their ability to manipulate light–matter interaction in both linear and non‐linear regimes at the nanoscale. Various metasurfaces display remarkable optical features, such as acute resonance, significant near‐field enhancement, and suitable capacity to support electric and magnetic modes, on account of the strong light–matter interaction and the low optical loss. Due to these important properties, they can be used in several advanced optoelectronic applications, like surface‐enhanced spectroscopy, photocatalysis, and sensing. This review reports on the recent progress of metamaterials and metasurfaces in molecular optical sensors. The principles that govern plasmonic and dielectric metasurfaces along with their features are outlined, supported by numerous examples. Then, the factors that result in a high Q‐factor are presented in order to show that metamaterials and metasurfaces can be used for label‐free sensing in a variety of detection mechanisms, including surface‐enhanced spectroscopy, refractometric sensing, and surface‐enhanced thermal emission spectroscopy via infrared absorption and Raman scattering, as well as chiral sensing. Finally, the challenges for future development are outlined. [ABSTRACT FROM AUTHOR]

In chemical engineering, the materials that is drawn or stretched continuously its surface velocity initially increases with distance from the orifice. The extruded material is also simultaneously cooled to provide solidification through a water bath or spraying with a coolant. Due to such applications and others, the present study concerns with the film deposition of Casson nanoliquid heat and mass transfer bioconvection flow with homogeneous‐heterogeneous chemical reactions, entropy generation, thermal radiation and magnetic dipole effects. The mechanical system has been proposed by the governing equations and boundary conditions which are simplified by the use of suitable similarity transformations. Homotopy analysis method is applied to obtain the series solution of non‐linear ordinary differential equations. Physical behaviors of heat and mass transfer flow with entropy generation and spray rate are investigated through the embedded parameters. Velocity is decreased with Casson nanofluid, ferromagnetic, porosity and inertial parameters while temperature is increased with thermal radiation, ferromagnetic, porosity and inertial parameters. Concentration of chemical reaction is increased with Schmidt and Reynolds numbers as well as heterogeneous chemical reaction parameter while motile microorganisms concentration is decreased with bioconvection Lewis, Peclet, and Reynolds numbers. Entropy generation is increased with thermal radiation, diffusivity and porosity parameters while spray rate is decreased with high values of film size. [ABSTRACT FROM AUTHOR]

The study concerns with the mechanical characteristics of rotating system of two double disks. Hall current effect, entropy generation, Arrhenius activation energy and binary chemical reactions are investigated in heat and mass transfer bioconvection flow of Maxwell nanofluid. Brownian motion and thermophoresis with thermal radiation and buoyancy effects are encountered in the governing equations. The mechanical system has been investigated by the governing equations and boundary conditions which are simplified by the use of suitable similarity transformations. Optimal homotopy analysis method is implemented to obtain the series solution of non‐linear ordinary differential equations. Physical behaviors of heat and mass transfer flow with entropy generation are investigated through the effects of embedded parameters. [ABSTRACT FROM AUTHOR]

The trivalent rare‐earth (RE3+) doped phosphors show tremendous achievement in narrow band multicolor line emission for various applications. However, the 4f–4f absorption transition of these ions is forbidden in UV and blue light excitation. Usually, a sensitizer having spin allowed transition was used as a co‐dopant to excite these ions via the energy transfer phenomenon. Another approach promisingly using to excite these ions by efficient energy transfer from the intrinsic emission of the Ca2LuTaO6 double perovskite phosphors host lattice. Phosphors of Ca2LuTaO6 with double perovskite structure were synthesized by using a high‐temperature solid‐state reaction method. The produced Ca2LuTaO6 double perovskite phosphors show an intrinsic broad band emission centered at 424 nm under the excitation of 313 nm UV light. The origin of this broad band blue emission was deeply investigated by using computation and experimental approaches. The trivalent activator Dy3+ and Eu3+ were doped is a single and co‐dopant in the produced Ca2LuTaO6 phosphors to check their excitation in UV and near‐UV spectral region. X‐ray diffraction and scanning electron microscopy were used to investigate the structure and phase analysis. Various characterizations such as photoluminescence excitation, emission, and CIE chromaticity coordinates were measured which illustrate the potential of Dy3+ and Eu3+ activated Ca2LuTaO6 double perovskite phosphors for narrow band multicolor line emission for various applications. [ABSTRACT FROM AUTHOR]

This study presents mechanisms for the investigation of an unsteady magnetohydrodynamic second‐grade fluid flow between two periodically oscillating plates. The flow characterization is given in three forms, that is, Couette flow, Poiseuille flow, and a combination flow of both of them. A mathematical system is generated to design the problems, which are solved in an analytical way with two novel procedures, namely Adomian decomposition method (ADM) and optimal homotopy asymptotic method (OHAM). The numerical comparison, absolute errors, and residuals of OHAM and ADM solutions are evaluated. Results obtained from these two methods are studied comparatively in the form of numbers and graphs. A good agreement between the respective data is obtained. The influences of flow parameters like frequency parameter, non‐Newtonian fluid parameter, magnetic field parameter, pressure gradient parameter, and time variable on velocity v(y, t) have been analyzed. [ABSTRACT FROM AUTHOR]

In recent years, seamless phase I/II clinical trials have drawn much attention, as they consider both toxicity and efficacy endpoints in finding an optimal dose (OD). Engaging an appropriate number of patients in a trial is a challenging task. This paper attempts a dynamic stopping rule to save resources in phase I/II trials. That is, the stopping rule aims to save patients from unnecessary toxic or subtherapeutic doses. We allow a trial to stop early when widths of the confidence intervals for the dose‐response parameters become narrower or when the sample size is equal to a predefined size, whichever comes first. The simulation study of dose‐response scenarios in various settings demonstrates that the proposed stopping rule can engage an appropriate number of patients. Therefore, we suggest its use in clinical trials. [ABSTRACT FROM AUTHOR]

This study explores the nexus between financial development, access to electricity, and CO2 emissions in Pakistan over the period from 1990 to 2015, incorporating the role of natural resources and population growth. We checked the stationarity of the data by using three different unit root tests (ADF, Phillip Pesaran, and DG‐FLS). Long‐ and short‐run elasticities have been determined through auto‐regressive distributive lag (ARDL) method. The empirical results confirmed that financial development and access to electricity increase CO2 emissions and deteriorate the environmental quality. In addition, the population growth is responsible for growing CO2 emissions in Pakistan, while natural resources have insignificant relation with CO2 emissions. Furthermore, bidirectional causality exists between population growth and natural resources, whereas unidirectional causality is detected among financial development and CO2 emissions, natural resources and population growth, and financial development and population growth. The newly developed findings suggest helpful policy implications to adequately address the issue of CO2 emissions without compromising economic development. [ABSTRACT FROM AUTHOR]

In this endeavor thin‐film flow of magneto hydrodynamic (MHD) fluid in the presence of thermal conductivity and variable viscosity over a porous steady stretching surface with a magnetic field and radioactive heat fluctuation is studied. In this phenomenon the viscosity vary inversely and thermal conductivity directly with temperature. The nonlinear coupled differential equations for the velocity and temperature profiles are achieved and solved by using a new analytical approach, called 3rd form of Optimal Homotopy Asymptotic Method (OHAM‐3). The proposed technique consists of initial guess, embedding parameter, optimal convergence control parameters, auxiliary functions and homotopy. Numerical (ND‐Solve Method) solutions are also achieved and compared with the results gained by the proposed method. The fast convergence of the applied new method and the influence of different physical nondimensional parameters on the velocity and temperature profiles are mainly focused in this research. [ABSTRACT FROM AUTHOR]

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BACKGROUND: This study highlights the effect of removing different plant parts on the biochemical changes in the garlic scape of cultivars G064 and G025 during controlled atmosphere storage (O2 = 2%–5%, CO2 = 3%–6%) at temperature = 0 ± 0.5 °C, Relative Humidity (RH) RH = 85%–95%, for 168 day. Total polyphenols (TP), total flavonoids (TF), the concentration of allicin, ethylene production and the antioxidant potential were evaluated and analyzed by using four different assays. Statistically significant differences were observed between different treatments. RESULTS: Total polyphenols, allicin concentration, and ethylene production were the highest in G064, while the total flavonoid concentration was the highest in G025. Removing the top resulted in the highest levels of total polyphenols, total flavonoids, allicin, and ethylene in both cultivars. The antioxidant capacity was also significantly higher when the top was removed than with other treatments in both cultivars. 2,2‐Diphenyl‐1‐picrylhydrazyl (DPPH), hydroxyl radical scavenging activity (HRSC), ferric ion reducing antioxidant power (FRAP) and metal‐chelating capacity (MCC) were higher in cultivar G064 compared to G025. CONCLUSION: Overall, the results suggest that the removing the tops of the scapes of G025 and G064 is the best treatment to maintain these biochemical changes. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Catalyst‐free solid phase Hantzsch synthesis of symmetric 4‐(3‐bromo‐4‐hydroxy‐5‐methoxyphenyl)‐2,6‐dimethyl‐3,5‐dicarbethoxy‐1,4‐dihydropyridine (4 a) and 4‐(3‐bromo‐4‐hydroxy‐5‐methoxyphenyl)‐2,6‐dimethyl‐3,5‐dicarbmethoxy‐(4‐nitrophenyl)‐1,4‐dihydropyridine (4 b) was carried out at 400 W under the microwave irradiation. The molecular crystal of both compounds were developed in a suitable solvents and characterized by X‐ray crystallographic method along with other spectroscopic techniques (viz. FT‐IR, 1H & 13C NMR, LC–MS, and elemental analysis). Single crystal structures of both compounds crystallizes in the orthorhombic and triclinic crystal systems with Cmc21 and P1 space groups consisting a=13.5755(13) Å, b=9.6755(9) Å, c=17.7625(17) Å, α=72.837(2)°, β=88.273(2)°, γ=75.221(2)° and a=8.9877(14) Å, b=11.1543(17) Å, c=12.2365(19) Å, α=90.00°, β=90.00°, γ=90.00° cell parameters, with 0.150 × 0.150 × 0.100 mm3 and 0.250 × 0.180 × 0.100 mm3 crystal size respectively. The 1,4‐DHP ring of both compounds have adopted a flattened boat‐type conformation and shows one and four intermolecular hydrogen bonds, respectively. A green approach has been taken into account for two new 1,4‐DHPs via Hantzsch synthesis without using solvent and catalyst under microwave irradiation at 400 W for 15 minutes to give an impressive yield percentage. The single crystal structures were developed and crystallized in the orthorhombic and triclinic crystal systems with Cmc21 and P1 space groups adopting the flattened boat‐type conformation for each one. [ABSTRACT FROM AUTHOR]

An efficient and highly regioselective BiIII catalyzed alcoholysis and Hydrochlorination reaction of spiro‐epoxy oxindole is demonstrated with alcohols and chlorine for easy access to 3,3‐disubstituted oxindoles. This protocol furnished alkyloxy and chlorinated products at the C3 spiro center of the epoxy ring in high yields up to 98 % with excellent regioselectivity > 99 %. The synthetic protocol was further exploited for the synthesis of the anti‐cancer active molecule, 1‐benzyl‐3‐(hydroxymethyl)‐3‐(phenylamino)indolin‐2‐one. Regioselective BiIII‐catalyzed alcoholysis and hydrochlorination reactions of spiro‐epoxy oxindoles offer an easy access to 3,3‐disubstituted oxindoles. These catalytic protocols give the alkoxy and chlorinated products at the C3 spiro center of the former epoxy ring in high yields (up to 98 %) and excellent regioselectivity (> 99 %). The synthetic protocol was further exploited for the synthesis of an anticancer active derivative. [ABSTRACT FROM AUTHOR]

Two‐dimensional ZnII/CdII‐based dual ligand metal–organic frameworks (MOFs) {[M(CHDC)(L)]⋅H2O}n involving 4‐pyridyl carboxaldehyde isonicotinoylhydrazone (L) in combination with flexible 1,4‐cyclohexanedicarboxylic acid (H2CHDC) as linkers have been synthesized by adaptable synthetic protocols including a green mechanochemical (grinding) method. Characterization, chemical/thermal stability, phase purity, and solid‐state luminescent properties of both MOFs have been established by various analytical methods. Structural analysis revealed dimeric metal clusters composed of [M2(CHDC)2]n loops doubly pillared with L, generating a 2D framework. Both MOFs can be used as highly active solvent‐free binary catalysts for CO2 cycloaddition with epoxides in the presence of the co‐catalyst tetrabutylammonium bromide (TBAB) with good catalytic conversion in up to six catalytic cycles without significant loss of activity. The present investigation demonstrates the application of MOFs as efficient heterogeneous catalysts for CO2 utilization under moderate reaction conditions. Based on the single‐crystal X‐ray data, a probable mechanism for the cycloaddition reaction has also been proposed. Going green: Green, ecofriendly mechanochemical synthesis of ZnII/CdII‐based mixed ligand metal–organic frameworks (MOFs) has been utilized as an efficient platform for heterogeneous catalysis of the cycloaddition of CO2 to epoxide at moderate and solvent‐free reaction conditions to give value‐added cyclic carbonates. [ABSTRACT FROM AUTHOR]

Abstract: Mixed‐ligand 3 D/2 D Zn metal–organic frameworks (MOFs) {[Zn(bdc)(L1)]⋅x G}n (ZnMOF‐1) and {[Zn(ipa)(L2)]}n (ZnMOF‐2; in which H2BDC=benzene‐1,4‐dicarboxylic acid, L1=4‐pyridyl carboxaldehyde isonicotinoylhydrazone, H2IPA=isophthalic acid, L2=3‐pyridyl carboxaldehyde nicotinoyl hydrazone, and G=lattice guests) were synthesized using versatile synthetic routes that include a green mechanochemical (grinding) reaction. Chemical and thermal stability, phase purity, and characterization of the ZnMOFs synthesized by different approaches were established by using various analytical methods. Both ZnMOFs can be used as a highly active, solvent‐free, binary catalyst for CO2 cycloaddition with epoxides under ambient reaction conditions of 1 atm pressure and room temperature/40 °C, in the presence of the cocatalyst nBu4NBr. The yield, recyclability, and stability of ZnMOF‐1 as a potential catalyst towards epoxide to cyclic carbonate conversion are excellent under ambient conditions. From literature and experimental inferences, a rationalized mechanism mediated by the Zn center of ZnMOFs for the CO2‐epoxide cycloaddition reaction has been proposed. To the best of our knowledge, very few MOF‐based catalysts have been reported to realize the conversion of CO2 to useful products under similar mild conditions. In the present investigation, that is, catalyst preparation by green mechanochemical synthesis and catalysis under ambient, solvent‐free conditions were performed with minimum energy utilization. [ABSTRACT FROM AUTHOR]

Abstract: Quinine thiourea organo‐catalyst immobilized on the SBA‐15 mesoporous material was synthesized by the post‐grafting method. First, the organothiol group was grafted over the SBA‐15 surface and which was anchored with quinine thiourea via. radical polymerization method. The synthesized catalyst was characterized by various physicochemical methods. The 13CP MAS solid‐state NMR confirms the successful grafting of quinine thiourea over the surface of SBA‐15. Thermogravimetric weight loss analysis confirms the successful anchoring of organo‐catalyst. The synthesized organo‐catalyst was used as heterogeneous catalyst for asymmetric Strecker reaction of N‐Boc isatin derived ketimines. The heterogeneous catalyst worked efficiently to give α‐amino nitriles in good yields and high enantiomeric excess up to 93% with 90% conversion in 85 h at –10 °C temperature. Furthermore, the catalyst was successfully reused up to five times without loss in yield and enantioselectivity of the product. [ABSTRACT FROM AUTHOR]

Abstract: A new class of CF3 substituted alkylidenemalonates were synthesized and used as a substrate for conjugate cyanation reaction. Ionic liquid has been used as an organocatalyst under solvent‐free and mild reaction conditions. The present protocol exhibited remarkable catalytic activity using a favourable cyanide source i. e. acetone cyanohydrin. Excellent yields were obtained for a wide range of substrates and the high reactivity is presumptively attributed to the basicity of an ionic liquid used. Mechanistic insights were studied using NMR spectroscopy and a probable catalytic cycle was proposed. [ABSTRACT FROM AUTHOR]

Abstract: A series of substituted spiro‐oxindole dihydrofuran ring derivatives were synthesized in good yields up to 94% and excellent diastereoselectivity ≥99% by simple tandem Michael ‐ cyclization in aqueous media using DABCO (1,4‐diazabicyclo[2.2.2]octane) as a catalyst and SDS (sodium dodecyl sulfate) as a promoter at ambient temperature. These molecules displayed promising antibacterial activity in vitro against pathogenic strains viz Vibrio cholerae, Escherichia coli, Bacillus subtilis, Bacillus licheniformis, Pseudomonas fluorescens, Salmonella enterica, Shigella flexneri and Shigella boydii with MIC (minimum inhibitory concentration), MBC (minimum bactericidal concentration) and IC50 (inhibitory concentration) values better than the standard antibiotic ampicillin. [ABSTRACT FROM AUTHOR]

New chiral macrocyclic cobalt(III) salen complexes were synthesized and used as catalyst for the asymmetric kinetic resolution (AKR) of terminal epoxides and glycidyl ethers with aromatic/aliphatic amines and water as nucleophiles. This is the first occasion where a Co(III) salen complex demonstrated its ability to catalyze AKR as well as hydrolytic kinetic resolution (HKR) reactions. Excellent enantiomeric excesses of the epoxides, the corresponding amino alcohols and diols (upto 99%) with quantitative yields were achieved by using the chiral Co(III) salen complexes in dichloromethane at room temperature. This protocol was further extended for the synthesis of two important drug molecules, i.e., ( S)-propranolol and ( R)-naftopidil. The catalytic system was also explored for the synthesis of chirally pure diols and chiral cyclic carbonates using carbon dioxide as a greener renewable C1 source. The catalyst was recycled for upto 5 catalytic cycles with retention of enantioselectivity. [ABSTRACT FROM AUTHOR]

Chiral macrocyclic CrIII salen complexes have been synthesized, characterized, and used as catalysts in the asymmetric aminolysis of aromatic ester epoxides with various anilines to prepare the β-amino- α-hydroxyl esters in very good yield (up to 95 %) along with high diastereo- and enantioselectivity ( dr>99/1, ee up to 96 %) under the optimized condition particularly with CrIII complex 4, which was effectively recycled four times. [ABSTRACT FROM AUTHOR]

A series of self-supported chiral polymeric MnIII N, N′-ethylenebis(salicylimine) (salen) complexes were synthesized through metalation of the corresponding salen ligands obtained by condensation of several bis/tris-aldehydes with (1 R,2 R)-1,2-diaminocyclohexane. Upon employment in the asymmetric epoxidation reaction of nonfunctionalized olefins, all complexes showed enhanced activity and enantioselectivity relative to the classical Jacobsen's monomeric salen complex. However, 1,3,5-triazole-based polymeric MnIII salen complex 7 was noticeably preferred over others owing to its ability to render higher enantioselectivity at the expense of lower catalyst loading. Furthermore, complex 7 was recycled and reused in eight recycling experiments with marginal loss in catalytic activity. [ABSTRACT FROM AUTHOR]

A series of new squaramide-based organocatalysts were synthesized from commercially available 3,4-dimethoxycyclobut-3-ene-1,2-dione in two steps. A 2.5 mol-% loading of the organocatalyst successfully catalyzed the asymmetric allylation of isatins with allyltributyltin to give the corresponding 3-allyl-3-hydroxyoxindoles in high yields and enantioselectivities (up to 98 % ee). [ABSTRACT FROM AUTHOR]

Magnetic-nanoparticle-supported phosphotungstic acid has been used to efficiently catalyze the hydrophosphonylation reaction of isatins, imines, and aldehydes using dimethyl and diethyl phosphite as a nucleophile to give the corresponding α-hydroxy and α-amino phosphonates in excellent yields for a wide range of substrates. The reaction conditions were simple, green, and efficient. The catalyst was recycled up to five times with retention of its activity. Based on the NMR spectroscopy studies, a probable catalytic cycle was proposed. [ABSTRACT FROM AUTHOR]

The present work demonstrates the use of phosphotungstic acid (H3PW12O40 ⋅H2O) as an efficient catalyst for the allylation of isatin derivatives as well as N- tert-butyloxycarbonyl (Boc)-α-amido sulfones with allyltributyltin as an allylating agent under solvent-free conditions at room temperature. Excellent allylation product yields of up to 99 % for the isatins substrates and good to excellent yields of up to 98 % for the N-Boc α-amido sulfones were obtained. The present allylation protocol is scalable as demonstrated by allylation of N-methylisatin at 1 g scale. Based on 1H, 13C, and 31P NMR studies a catalytic cycle was proposed for allylation of isatins as well as N-Boc amido sulfones. The allylation products N-Boc homoallyl amines were successfully epoxidized to get multifunctional compounds, which are valuable intermediates for natural products and bioactive compounds. [ABSTRACT FROM AUTHOR]

The salalen and salan ligands have been synthesized by the reactions of ( S)-pyrrolidin-2-ylmethanamine and salicylaldehyde derivatives. These ligands were treated with Mn(CH3COO)2 ·4H2O followed by air oxidation to give ( S, R)-MnIII-salalen and -salan complexes in yields of 84-88 %. The absolute configuration of ( S, R)-MnIII-salalen was determined by single-crystal X-ray diffraction and CD analysis of the ligands and complexes showed similiar Cotton effects. The MnIII-salalen and -salan complexes were screened for their catalytic activity in the asymmetric Strecker reaction. ( S, R)-2,4-Di- tert-butyl-6-({[1-(3,5-di- tert-butyl-2-hydroxybenzyl)pyrrolidin-2-yl]methylimino}methyl)phenolatomanganese(III) chloride (5 mol-%) was found to be a suitable catalyst for the asymmetric Strecker reaction of N-(4-methoxybenzylidene)diphenylmethanamine with ethyl cyanoformate, which gave 89 % yield and 55 % ee of 2-(benzhydrylamino)-2-(4-methoxyphenyl)acetonitrile at -15 °C after 24 h. [ABSTRACT FROM AUTHOR]

A diethyl tartrate linked chiral macrocyclic manganese(III)-salen (salen= N, N′-ethylenebis(salicylimine)) complex has been used for the enantioselective epoxidation of nonfunctionalized alkenes, namely, indene and chromenes, as well as oxidative kinetic resolution of racemic alcohols. For the epoxidation reaction, a 2.5 mol % catalyst loading in the presence of pyridine N-oxide as an axial ligand and urea-H2O2 adduct as an oxidant gave respective epoxides in high yield (>97 %) and enantiomeric excess ( ee, up to 92 %). The same catalyst at a loading of 1.5 mol % has provided enantioenriched ( ee up to 97 %) secondary alcohols through oxidative kinetic resolution of racemic alcohols. The catalyst can be recovered and reused up to four times with no loss in performance. [ABSTRACT FROM AUTHOR]

Chiral AlIII salen complexes were synthesized and used as catalysts for the asymmetric hydrocyanation of nitroolefins using 4-phenylpyridine N-oxide as an additive and trimethylsilyl cyanide (TMSCN) as a source of cyanide. An excellent yield of β-nitronitrile (87 %) and enantioselectivity (90?%) were achieved if (2-nitrovinyl)cyclohexane was used as a substrate at -15?°C in 16 h. To understand the interaction of the AlIII salen complex and additive, NMR and IR spectroscopic studies revealed that 4-phenylpyridine N-oxide acts both as an axial ligand and helps to activate the cyanide source TMSCN, which thereby increases the reactivity. A catalytic cycle was proposed based on the spectroscopic studies. [ABSTRACT FROM AUTHOR]

Chiral copper(II) polymeric [H4]salen (salen=bis[(salicylidene)ethylenediaminato]) complexes CuII-1- 3 were generated in situ and used as efficient catalysts in the asymmetric Henry and aza-Henry reaction of various aromatic and aliphatic aldehydes and N-tosylimines in the presence of various nitroalkanes at room temperature (27±2 °C) for 20 hours. This group of polymeric [H4]salen complexes demonstrated excellent performance (product yield and enantiomeric excess ee up to 98 %) in the formation of β-nitroalcohol by using nitromethane with low catalyst loading of 1 mol % (with respect to the monomeric salen unit) and high enantioinduction ( ee 94 %) in the aza-Henry product; β-nitroamines were obtained with moderate yield (78 %). This catalytic system also worked well with nitroethane and 1-nitropropane in the case of Henry reaction, to furnish the corresponding products in high yields and enantioselectivities for syn diastereomers. The CuII-2 complex retained its performance at the gram level and was expediently recycled eight times with no significant loss in its performance. The kinetic study with CuII-2 complex for the enantioselective aza-Henry reaction of N-Ts-benzylimine (Ts=tosyl) revealed a first-order dependence on catalyst and nitromethane concentration and was zero order with respect to the substrate. The product obtained was transformed straightforwardly to the pharmaceutically important enantiomerically pure ( R) -tembamide (β-adrenergic agonist) drug in good yield by the asymmetric nitroaldol reaction of 4-methoxybenzaldehyde in three successive steps. [ABSTRACT FROM AUTHOR]

A chiral oxazoline-based organocatalyst has been found to efficiently catalyze asymmetric Strecker reactions of various aromatic and aliphatic N-benzhydrylimines with trimethylsilyl cyanide (TMSCN) as a cyanide source at −20 °C to give α-aminonitriles in high yield (96 %) with excellent chiral induction (up to 98 % ee). DFT calculations have been performed to rationalize the enantioselective formation of the product with the organocatalyst in these reactions. The organocatalyst has been characterized by single-crystal X-ray diffraction analysis, as well as by other analytical methods. This protocol has been extended to the synthesis of the pharmaceutically important drug molecule levamisole in high yield and with high enantioselectivity. [ABSTRACT FROM AUTHOR]

New chiral ligands, ( S,R,S)- 1, ( S,S,S)- 1, ( S,S,R)- 1, ( S,R,R)- 1, ( R,R,R)- 1, ( R,R,S)- 1, ( R,S,S)- 1, ( R,S,R)- 1, ( S,R,S)- 2, ( S,S)- 3 and ( R,S)- 4 with diverse stereogenic centers arising from various diastereomeric combinations of aminoalcohol functionality with ( R)- and ( S)-1,1-binaphthol, were prepared and characterized. Catalytically active Ti complexes were generated in situ in the presence of water for the enantioselective ring-opening reaction of meso-stilbene oxide, cyclohexene oxide, cyclopentene oxide, and cis-butene oxide with different anilines as nucleophile. Significantly, catalysts Ti-( S,R,S)- 1 and Ti-( R,S,S)- 1 (15 mol %) produced syn-beta-amino alcohols of meso-stilbene oxide with (1 S,2 S) and (1 R,2 R) configuration respectively in excellent yields (>98 %) and enantioselectivities ( ee value >99 %) in 10 h at room temperature. However, aliphatic/cyclic epoxides with aniline gave better performance with the catalyst Ti-( S,R,R)- 1. The complex Ti-( S,R,S)- 1 was successfully subjected to catalyst recovery and recyclability experiments over 6 cycles in the asymmetric ring-opening of meso-stilbene oxide with aniline with retention of performance. [ABSTRACT FROM AUTHOR]

A convenient approach to the asymmetric Strecker reaction was established by synthesizing chiral, mono- and dinuclear, macrocyclic MnIII-salen complexes possessing achiral and chiral linkers (trigol, piperazine, and diethyl tartarate). This group of macrocyclic complexes has emerged as improved metal-based catalysts for the enantioselective Strecker reaction of aldimines, giving high enantioselectivity (up to 99 %) for a wide range of substrates. The macrocylic complex 6 a with trigol linker works very well with TMSCN (trimethylsilyl cyanide) as a source of cyanide, using 4-phenyl pyridine N-oxide (4-PPyNO) as a co-catalyst in toluene at −40 °C. However, the macrocyclic complex 6 b with diethyl tartarate as a linker affected excellent chiral induction for both aromatic and aliphatic imines with a safer cyanide source (ethyl cyanoformate) in toluene at −20 °C in the presence of N, N-diisopropylimine as a co-catalyst. Complexes 6 a and 6 b used in the present study were recoverable and recyclable (five times) with retention of their performance at gram level. The kinetic study with complex 6 a for the enantioselective Strecker reaction of N-benzyl benzylimine revealed a first-order dependence on catalyst, substrate, and TMSCN concentration. This protocol with catalyst 6 b was further extended for the synthesis of D-homophenyl alanine, an important analogue in factor Xa inhibitors. [ABSTRACT FROM AUTHOR]

Chiral macrocyclic TiIV-salen complexes were used as efficient catalysts in the asymmetric cyanoethoxy carbonylation of aldehydes. The TiIV catalysts demonstrated excellent performance (product yields and ee values up to 99 %) with ethyl cyanoformate as the cyanide source and a catalyst loading of 0.5 mol %, which is the lowest known. The macrocyclic TiIV-salen complex retained its performance at multigram level and was conveniently recycled for a number of times. The product obtained was straightforwardly transformed to the pharmaceutically important chiral drugs ( R)-proethalol (β-blocker) and ( R)-phenylephrine (α1-adrenergic receptor agonist) in good yields. To understand the mechanism of the catalytic reaction, a kinetic investigation was conducted with various concentrations of the catalyst, ethyl cyanoformate and benzaldehyde as the representative substrate. The reaction of benzaldehyde was first order with respect to the concentration of the catalyst and the ethyl cyanoformate but did not depend on the initial concentration of the substrate. A possible mechanism of the cyano-ethoxy carbonylation reaction was proposed. [ABSTRACT FROM AUTHOR]

ABSTRACT We are reporting the synthesis, characterization, and calf thymus DNA binding studies of novel chiral macrocyclic Mn(III) salen complexes S-1, R-1, S-2, and R-2. These chiral complexes showed ability to bind with DNA, where complex S-1 exhibits the highest DNA binding constant 1.20 × 106 M−1. All the compounds were screened for superoxide and hydroxyl radical scavenging activities; among them, complex S-1 exhibited significant activity with IC50 1.36 and 2.37 μM, respectively. Further, comet assay was used to evaluate the DNA damage protection in white blood cells against the reactive oxygen species wherein complex S-1 was found effective in protecting the hydroxyl radicals mediated plasmid and white blood cells DNA damage. Chirality 24:1063-1073, 2012.© 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article presents the result of the study on the Reservoir Optimization-Simulation with Sediment Evacuation (ROSSE) model applied in the Tarbela Reservoir in Pakistan to optimize and simulate its operation with sediment evacuation. It mentions that the ROSSE model, which uses the genetic algorithm based optimization capabilities and embeds the sediment evacuation model into the simulation model, is applied to optimize the rule curves of the reservoir. In this relation, the study concludes that it is possible to enhance the reservoir's sustainability and maximize its net income benefits by modifying the operating policy and rule curves.