bluuebunny/crossref_metadata_2025_split huggingface dataset:
Particle Size and Shell Thickness Dependence of the Light Intensity Enhancement in the Cap Layers of Ag, Au, Al and SiO2@TiO2 Core‐Shell Nanostructures
Authors: Bascura Erdem B. , Karakurt Ismail 
Published: April 2018

AbstractWe present a systematic study of the light intensity enhancement in the shell layers of half burrried Ag, Au, Al and SiO2 spherical nanoparticles capped with TiO2. We calculated the light intensity profiles near these structures when they are illuminated by a UV light at 380 nm. The calculations cover the particle‐size range between 20 and 180 nm, and the cap thickness range between 6 and 80 nm. Our data is the first report on the intensity enhancement in the shell layers of TiO2‐capped Al nanoparticles and Al@TiO2 core‐shell nanostructures. We obtain, in the cap layers, an average intensity enhancement of ∼3.7, ∼6.1, ∼2.4 and ∼2.7 for a cap thickness of ∼30 nm above Ag, Al, Au and SiO2 particles. Taking into account the increase in the active surface area, these numbers can be multiplied by a factor of two, for each capped‐nanoparticle system. The optimal Ag, Au, Al and SiO2‐particle sizes for a 30‐nm cap‐thickness are found to be 120 nm, 80 nm, 140 nm, and 80 nm. While half‐buried and capped‐nanoparticle systems resemble the typical core‐shell nanoparticles, the intensity enhancements are not equivalent. We compare the intensity increases in these two systems at the optimal sizes for Ag and Al particles for a 30‐nm shell thickness.
Synthesis and Biological Evaluation of Thieno[2, 3‐d]pyrimidine‐amides as Potential Anticancer Agents
Authors: Ramya Posa Venkata Sri , Thatikonda Sowjanya , Angapelly Srinivas , Babu Bathini Nagendra , Naidu Vegi Ganga Modi , Kamal Ahmed 
Published: April 2018

AbstractIn our search towards the development of potential anticancer agents, a new class of N‐(3‐(thieno[2, 3‐d]pyrimidin‐4‐ylamino)phenyl)amides (10 a−x) were synthesized and examined for their anticancer activity towards different human cancer cell lines. Of the derivatives tested, 10 g, 10 p and 10 w displayed potent growth inhibition on some of the cell lines, peculiarly 10 w exhibited selective and promising activity on MDA‐MB‐453 and MCF‐7 cell lines. In comparison to the standard ZSTK474, nearly 3 fold growth inhibitory effect was noticed with 10 w against MCF‐7 cell line. Notably, the morphology and long term clonogenic survival of MCF‐7 cells were affected by compound 10 w. Moreover, the results from AO/EB and DAPI staining studies as well as analysis of mitochondrial membrane potential divulged that the growth of MCF‐7 cells was inhibited by 10 w through the induction of apoptosis. From flow‐cytometry analysis, it is notable that 10 w shows G0/G1 cell cycle arrest in MCF‐7 cells. Overall, compound 10 w could be considered as a promising lead for the further exploration and identification of thieno[2, 3‐d]pyrimidine‐based anticancer agents.
Graphene Oxide‐Supported Hypervalent Organoiodine (III): Recyclable Reagent for Selective and Metal‐Free Oxidation of Alcohols
Authors: Ghanbari Nastaran , Ghafuri Hossein , Zand Hamid Reza Esmaili 
Published: April 2018

AbstractIn this research, main emphasis has been placed on the oxidizing properties of graphene oxide (GO) and hypervalent organoiodine (III) (HVI) and their oxidizing effect in GO‐HVI. GO‐HVI as a metal‐free, environment‐friendly, recyclable and efficient heterogeneous reagent was synthesized and completely characterized by Fourier transform infrared spectroscopy (FT‐IR), energy dispersive X‐ray (EDX), field emission scanning electron microscopy (FE‐SEM), X‐ray diffraction, and atomic force microscopy (AFM). The synthesized GO‐HVI was used to achieve an effective and selective method for oxidation of various alcohols. All substituted alcohols were oxidized in good to excellent yields under mild conditions at room temperature. The oxidizing ability of GO‐HVI was higher in comparison with starting GO and HVI. This GO‐HVI have great stability and could be recycled six times without noteworthy loss of activity.
γ‐Fe2O3@SiO2‐EC‐ZnII: A Magnetic Recyclable Nanocatalyst for the Synthesis of Spiro[indoline‐3, 9′‐xanthene]trione Derivatives in Aqueous Media
Authors: Ghasemzadeh Maryam Sadat , Akhlaghinia Batool 
Published: April 2018

AbstractIn this research, ZnII immobilized on creatinated epibromohydrin functionalized γ‐Fe2O3@SiO2 nanoparticles (γ‐Fe2O3@SiO2‐EC‐ZnII) as a novel magnetic nanostructured heterogeneous catalyst has been prepared readily and fully characterized by some spectroscopic and microscopic techniques such as fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction analysis (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), dynamic light scattering (DLS), EDS‐map, inductively coupled plasma atomic emission spectroscopy (ICP‐OES) and CHNS. The above experimental results determined the composition of γ‐Fe2O3@SiO2‐EC‐ZnII and clearly revealed the core‐shell structure nanoparticles are spherical in shape with the particle size in the range of 7–23 nm and superparamagnetic behavior. The magnetic nanostructured catalyst was identified as an efficient catalyst for the rapid synthesis of a library of spiro[indoline‐3, 9‐xanthene]trione derivatives via the condensation reaction of different substituted isatins and dimedone or 1,3‐cyclohexanedione at room temperature in aqueous media. Environmental friendliness, aqueous reaction medium, low cost, high yields, short reaction times, operational simplicity, wide applicability, magnetic recovery of catalyst and reusability up to seven cycles, as the important features of this protocol make the present methodology sustainable and economic.
Design and Synthesis of 2‐Amino‐thiophene‐Tethered Ureidopenicillin Analogs with Potent Antibacterial and Antitubercular activity
Authors: Wagh Mahendra A. , Baravkar Sachin B. , Jedhe Ganesh S. , Borkute Rachna , Choudhari Amit S. , Sarkar Dhiman , Sanjayan Gangadhar J. 
Published: April 2018

AbstractUreidopenicillins are a class of penicillins which are antibiotics active against gram‐negative bacteria. Herein, we report the synthesis of 2‐aminothiophene‐tethered ureidopenicillin analogues and their in vitro antibacterial and antitubercular activity. Intriguingly, unlike the reported ureidopenicillins which are active against gram‐negative bacteria, the synthesised 2‐aminothiophene‐tethered ureidopenicillins were significantly active against Gram‐positive bacterial strains and showed moderate inhibition towards gram‐negative bacterial strains. Among all the analogs, compound 1 b containing 2‐aminothiophene moiety with minimum inhibitory concentration (MIC): 0.29, 0.32, > 10, > 10 μg/ml for Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa, respectively, showed better anti‐bacterial profile as compared to cephalexin and equipotent to ampicillin and amoxicillin on gram‐positive bacterial strains. All the derivatives were also screened for anti‐TB activity against mycobacterium tuberculosis H37Ra. Among the series, cycloocta‐thiophene‐tethered cephalexin analog 3 c displayed excellent antitubercular activity with MIC values 0.78 μg/ml. Low cytotoxicity and high selectivity index indicate the efficacy of 3 c against mycobacterial infections. The results from present study offer a novel approach to modify the existing drug class of ureidopenicillins to yield antimicrobials with promising utility.
AlNb/SBA‐15 Catalysts with Tunable Lewis and Bronsted Acidic Sites for Glucose Conversion to HMF
Authors: Wang Yong , Zhu Liwei , Zhang Yuan , Cui Hongyou , Yi Weiming , Song Feng , Zhao Pingping , Sun Xiuyu , Xie Yujiao , Wang Lihong , Li Zhihe 
Published: April 2018

AbstractIn this paper, a series of AlNb/SBA‐15 catalysts with various Al/Nb atom ratios were prepared by impregnation method for efficient conversion of glucose to 5‐hydroxymethylfurfural (HMF). Characterization by SEM, TEM, BET and XRD showed that the microstructure after impregnation of the active components was preserved, similar to that of SBA‐15, although the pore size and specific surface area decreased to some extent with the increase of Al/Nb atom ratio due to the thickening of the pore wall, which was due to the deposition of the active component salts. Py‐IR and NH3‐TPD analysis indicated that AlNb/SBA‐15 had both Bronsted acid sites and Lewis acid sites simultaneously after incorporation of the Al species and they were tunable by adjusting the Al/Nb atom ratio. The catalyst with Al/Nb atom ratio of 2:3 exhibited the suitable strength of Lewis and Bronsted acid and the highest total acid amount, as a result, showing the highest catalytic activity in glucose dehydration to HMF. As high as 55.7% of HMF yield with 93.4% glucose conversion was obtained when reacting at 170 °C for 6.0 h using methyl iso‐butyl ketone (MIBK)/water with a volume ratio of 2 as the reaction media.
Support‐Independent Surface Functionalization for Efficient Pd Loading in Catalytic Hydrogenation
Authors: Fu Peng , Xiao Zhourong , Liu Yanhong , Wang Li , Zhang Xiangwen , Li Guozhu 
Published: April 2018

AbstractNoble metal catalysts supported on high‐surface‐area supports are of great importance as heterogeneous catalysts in numerous industrial processes. Control of the nanostructures and distribution of metal nanoparticles (NPs) is a key to achieving high activity. Surface functionalization has received much attention for efficient loading of metal NPs. In this study, surface functionalizations of various supports including SBA‐15, Al2O3, reduced graphene oxide (RGO), and carbon nanotubes (CNTs) have been carried out to facilitate palladium loading. The as‐synthesized supported palladium (Pd) catalysts have been studied by evaluating their catalytic activity for 4‐nitrophenol (4‐NP) hydrogenation in water at room temperature. Transmission electron microscopy and energy‐dispersive X‐ray mapping were used to characterize the catalysts. The results show that the strategy of support surface functionalization for Pd loading is generally applicable to various supports and different reactions of hydrogenation. Catalysts with elevated activity in catalytic hydrogenation have been obtained via efficient Pd loading by the surface functionalization of support. Moreover, kinetic study has been conducted on 4‐NP hydrogenation catalyzed by Pd/SAM‐DA‐CNT (Pd nanoparticles supported on CNTs modified by polydopamine and carboxylic acid‐terminated alkanethiol monolayer). The obtained kinetic data are fitted to a Langmuir‐Hinshelwood (L−H) model, and the calculated apparent activation energy of this process is 65.39 kJ mol−1.
Monodentate Coordination of N, N′‐Disubstituted Thiocarbamide Ligands: Syntheses, Structural Analyses, In Vitro Cytotoxicity and DNA Damage Studies of Cu(I) Complexes
Authors: Pandey Sunil K. , Singh Durga P. , Marverti Gaetano , Butcher R. J. , Pratap Seema 
Published: April 2018

AbstractStructural analysis of three novel substituted thiocarbamide ligands N‐(naphthyl)‐N′‐(isobutoxycarbonyl) thiocarbamide (H2L1), N‐(4‐methoxyphenyl)‐N′‐(isobutoxycarbonyl) thiocarbamide (H2L2) & N‐(2‐methoxy‐4‐nitrophenyl)‐N′‐(isobutoxycarbonyl) thiocarbamide (H2L3) and their copper(I) complexes [(H2L1)2CuCl] (1), [(H2L2)2CuCl] (2) and [(H2L3)2CuCl] (3) was performed using various spectroscopic techniques (FT−IR, 1H and 13C NMR, UV‐Visible),TG analysis and single crystal X‐ray studies of (H2L1) and [(H2L1)2CuCl] (1). The copper(I) complexes possess trigonal planar geometry coordinating through two thione sulfur atoms from two ligand molecules and one chloride ion. Two intramolecular hydrogen bonding interactions present between (−N1H) and carbonyl oxygen (−N2H) and coordinated chlorine stabilize the trigonal planar structure of the complexes. Cyclic voltammogram of complexes 1–3 displayed quasireversible redox behaviour corresponding to CuI/CuII couple. Determination of in vitro cytotoxicity of ligands and their complexes using five human carcinoma cell lines 2008, C13* (cervical carcinoma), A2780, A2780/CP and IGROV‐1 (ovarian carcinoma) revealed that copper(I) complexes were more potent inhibitors than the ligands against all the cell lines. The most effective were complexes 2 and 3. The comet assay test of complexes 2 and 3 against 2008, C13* and IGROV‐1 cell lines indicated significant damage to the DNA structure.
Chemo‐Biocatalytic Oxidative Condensation of Natural Arylpropene with 2‐Aminobenzothiazole into Schiff‐Bases as Potent Anti‐Amyloid Agents: Studies Employing Transgenic C. elegans
Authors: Saima  , Kumar Lalit , Lavekar Aditya G. , Sharma Tanuj , Shamsuzzama  , Equbal Danish , Siddiqi Mohammad Imran , Sinha Arun K. , Nazir Aamir 
Published: April 2018

AbstractCombining natural scaffolds with potent heterocyclic pharmacophores to have extra ordinary potency of synthetic hybrid molecules has gained significant attention as these compounds possess diverse biological activities including ameliorative effects against Alzheimer disease (AD) associated endpoints. In this context, a chemo‐biocatalytic protocol has been described wherein 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) catalyzed oxidation of natural methoxylated phenylpropenes into corresponding cinnamaldehydes followed by Bovine serum albumin (BSA)‐catalyzed condensation reaction with heterocyclic amine in water provides a series of Schiff bases in moderate to good yield. Interestingly, some of the 2‐aminobenzothiazole based Schiff bases with dioxymethylene substituted cinnamaldehydes, an oxidized product of natural isosafrole, appear as an multifunctional agents which significantly decreased the disease associated endpoints in C. elegans model of Alzheimer's disease. These Schiff bases exerted their effect by reducing Aβ aggregation, decreasing lipid deposition and oxidative stress, thereby preventing cholinergic neuronal degeneration. All these properties highlight the therapeutic potential of these prototypes to be developed as new multifunctional drug candidates in the treatment of Alzheimer's disease. Moreover, molecular modeling studies have revealed the interaction of Schiff base with acetylcholine receptors.
Er(OTf)3‐Catalyzed Multicomponent Synthesis of 3,4‐Dihydro‐2H‐pyran via Hetero‐Diels‐Alder Reaction under Ambient Temperature
Authors: Ramesh Vediyappan , Shanmugam Sivakumar , Devi Natarajan Savitha 
Published: April 2018

AbstractA one‐pot synthesis of 3,4‐dihydro‐2H‐pyran derivatives has been achieved using substituted styrenes, aqueous formaldehyde and various β‐keto esters. This multicomponent protocol employs erbium (III) triflate as a catalyst affording 3,4‐dihydro‐2H‐pyran derivatives in good to excellent yields (72‐98%). Furthermore, synthesis of the bicyclic fused ring system such as 2‐aryl‐2,3,4,6,7,8‐hexahydro‐5H‐pyrano[2, 3‐d]pyridazin‐5‐one 6 was achieved from the corresponding 3,4‐dihydro‐2H‐pyran 4.
Spinel‐Type Mixed Oxides for Stable and Selective Partial Oxidation of Benzyl Alcohol
Authors: Gurrala Lakshmiprasad , Nagpure Atul S. , Gurav Hanmant R. , Chilukuri Satyanarayana 
Published: April 2018

AbstractBenzaldehyde is an important chemical intermediate, which need to be prepared through an eco‐friendly process. Manganese oxides are active as catalysts for its preparation through partial oxidation of benzyl alcohol. In this study, Cu, Co and Mn containing spinel based mixed oxides (CuxMn3−xO4) were prepared and tested for partial oxidation of benzyl alcohol to get benzaldehyde with high selectivity. The catalytic activity strongly depended on chemical composition, acid‐base properties and oxygen uptake. The influence of chemical composition, reaction temperature, oxygen partial pressure and the weight hourly space velocity (WHSV) were investigated to optimize benzaldehyde yield and to stabilize the catalyst activity. A high benzaldehyde selectivity of 98%, accompanied with benzyl alcohol conversion of 84.5% was obtained over Cu0.25Mn2.75O4 catalyst at 300 °C. It was evident from temperature programmed desorption (TPD) of CO2 that this catalyst was found to have optimum basicity and high oxygen uptake, thus imparting high activity and stability. Activity and catalyst life could be attributed to appropriate acid‐base properties.
One‐pot, Multi‐Component Synthesis of Novel Bis‐Spiro Pyranopyrazole Derivatives in the Presence of DABCO as an Efficient and Reusable Solid Base Catalyst
Authors: Safari Ensieh , Hasaninejad Alireza 
Published: April 2018

AbstractA simple and elegant synthesis of some novel bis‐spiro pyranopyrazoles has been achieved via the condensation reaction between bis‐isatins, malononitrile, hydrazine hydrate and ß‐ketoester derivatives in the presence of a catalytic amount of 1, 4‐diazabicyclo [2.2.2] octane (DABCO) in ethanol at reflux conditions. The significant features of the present method are structure diversity, product complexity, procedure and work‐up simplicity, environmentally friendly, good to excellent yields and catalyst recyclability.
Sodium Salts of Substituted Tetracyanocyclopentadienides [C5(CN)4X]− (X= H, CN, NH2, NO2): Substituent Influence on the Crystal Structures of Potential Coordination Polymers.
Authors: Nimax Patrick R. , Sünkel Karlheinz 
Published: April 2018

AbstractMetathesis reactions of NaCl with the silver salts of substituted tetracyanocyclopentadienides [C5(CN)4X]− (X= H, CN, NO2, NH2) gives the corresponding sodium salts 1–4. While 1–3 give polymeric networks, held together by Pi‐stacking as well as multiply bridging polydentate cyanocyclopentadienides and in part hydrogen bonda, the aminotetracyanocyclo‐pentadienide 4 forms only a water‐bridged dinuclear complexes, which are connected only by an intensive hydrogen bond network. Quite surprisingly, only the NO2‐substituent in 3 coordinates to Na+ besides the cyano groups, while the NH2 group in 4 is only involved in hydrogen bonds.
Technique and results of the first six cases of anal sphincteroplasty with Deoti's flap for complex anatomical deformity of the perineum
Authors: Rodrigues Beatriz Deoti Silva , Reis Igor Guedes Nogueira , Daldegan Isabelle Reis , Buzatti Kelly Cristine de Lacerda Rodrigues 
Published: April 2018

Abstract
Objectives Anal sphincteroplasty with Deoti's flap is a recently published procedure for the treatment of fecal incontinence with severe perineal deformity. The aim of this study is to report six cases of patients, analyzing their results in fecal incontinence questionnaires and proposing a new scale to better assess our technique's main objective, the reconstruction of the perianal anatomy.
Methods Six patients were submitted to anal sphincteroplasty with Deoti's flap and follow-up was performed every six months. Functional results and Quality of Life were measured by Wexner Score and Fecal Incontinence Quality of Life Scale, respectively.
Results All operations were carried out without failure to perform Deoti's flap rotation. The sample presented medians of 18.5 and 3.5 on Wexner Score, before and after surgery, respectively. In the Fecal Incontinence Quality of Life Scale, the medians before and after surgery are, respectively, 1.75 and 3.35 (Scale 1), 1.54 and 2.60 (Scale 2), 2.35 and 3.28 (Scale 3), 1.49 and 3.33 (Scale 4). The p-values were 0.0173 for Wexner Score and 0.0260, 0.0411, 0.0368 and 0.0952 for Scales 1, 2, 3 and 4 of Fecal Incontinence Quality of Life Scale, respectively. All patients presented sustained improvement in Wexner Score and in quality of life questionnaire (in all scales of Fecal Incontinence Quality of Life Scale).
Conclusions Deoti's surgical flap with sphincteroplasty successfully reconstructs complex anatomical deformities of the perineum. Current questionnaires to assess fecal incontinence may not evaluate properly the anatomical result of the technique, thus we propose a visual scale. In addition, sphincteroplasty with Deoti's flap may have longer-term outcomes in functional results than sphincteroplasty alone.
Vitamin D: And its role in breast cancer
Authors: de La Puente‐Yagüe Miriam , Cuadrado‐Cenzual Maria A. , Ciudad‐Cabañas María J. , Hernández‐Cabria Marta , Collado‐Yurrita Luis 
Published: April 2018

AbstractVitamin D is a fat soluble vitamin that plays a role in calcium and phosphorus homeostasis. Recently, extensive research on its extraskeletal actions has linked vitamin D deficiency to an increased risk of infection, diabetes mellitus types 1 and 2, cardiovascular disease, obesity, asthma, inflammatory bowel disease, colon, breast, prostate and ovarian cancer and some neurological diseases. There are various mechanisms by which vitamin D influences the natural history of cancer. These include the role of vitamin D in the induction of apoptosis, stimulation of cell differentiation, anti‐inflammatory and antiproliferative effects and inhibition of angiogenesis, invasion and metastasis. The aim of this review is to clarify the true role of vitamin D in the onset of breast cancer and evolution of the disease after treatment. A further aim is to suggest new research directions to identify indications and requirements for vitamin D supplementation in patients with breast cancer.
Effect of Wheelchair Stroke Pattern on Upper Extremity Muscle Fatigue
Authors: Bickelhaupt Brittany , Oyama Sakiko , Benfield Jonathan , Burau Keith , Lee Shuko , Trbovich Michelle 
Published: April 2018

AbstractBackgroundShoulder dysfunction is common in persons with spinal cord injury (SCI) with an incidence of up to 63%. Dysfunction is a result of muscle imbalances, specifically denervated rotator cuff muscles that are repetitively used during manual wheelchair propulsion.ObjectiveTo determine which arm stroke technique, pump (P) or semicircular (SC), is most energy efficient for long periods of propulsion.DesignA randomized study with repeated measures observations.SettingThe study was performed at an institutional gait analysis laboratory.Participants18 able‐bodied (AB) male participants were studied and randomized into one of 2 conditions, SC or P.MethodsShoulder muscle fatigue was measured by changes in Borg CR10 Rate of Perceived Exertion (Borg RPE) and upper extremity strength via a handheld dynamometer. Participants were studied and assigned into one of 2 conditions of wheelchair arm propulsion patterns, SC or P group, and propelled on a wheelchair treadmill for 10 minutes.Main Outcome MeasuresThe primary outcomes included recordings of Borg RPE scale during continuous wheelchair propulsion and pre‐ and post‐test dynamometer testing means for bilateral elbow and shoulder extension. Analysis of covariance, t‐tests, and Kruskal‐Wallis tests were used in analyzing data.ResultsAlthough not significant (P = .23), the Borg RPE scores for the SC condition were consistently higher than the scores for the P condition. In addition, the dynamometer pre‐ and post‐test readings demonstrated a larger decrease for the SC condition participants than for the P condition participants, but were not statistically significant.ConclusionsThese data demonstrate that the SC wheelchair propulsion pattern appears to be more fatiguing to shoulder muscles than the P propulsion pattern. However, more data would need to be collected to find a significant difference.Level of EvidenceII