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Recently, CaO‐doped (≤4 mol.%) tetragonal zirconia (CaSZ) ceramic was recommended as a potential alternative to yttria‐stabilized ZrO2 (YSZ). Here, we investigate the limits of starting particle sizes on the stability of tetragonal (t) phase and other associated benefits on measured properties. Synthesized CaSZ powders calcined with different temperatures were used as a mono‐sized or mixed (i.e., two different calcination temperatures) batch fraction for making dense CaSZ ceramic. The mixed‐batch powders were found to be far more efficient in stabilizing the t‐phase in ceramic. Compared to YSZ, CaSZ recorded remarkable enhancement in toughness (up to 8.3 MPa m$\sqrt {\mathrm{m}} $). Contrary to YSZ, CaSZ ceramic demonstrated outstanding thermal stability. [ABSTRACT FROM AUTHOR]

Mixed‐mode chromatography open tubular column has been developed for peptide separation in electrochromatography. A column with 92 cm effective length and 50 μm internal diameter is fabricated internally with a copolymer sheet of restricted thickness. Catalyst facilitated binding of the coupling agent 3,5‐bis (trifluoromethyl) phenyl isocyanate has been carried out at the interior surface of the column. The initiator sodium diethyldithiocarbamate was bound to the coupling agent. A small amount of N‐[2‐(acryloylamino) phenyl] acrylamide was used along with methacrylic acid and styrene in the monomer mixture to induce a little polar character in the stationary phase fabricated inside the column. Twenty‐three peptides have been separated from a chemically digested protein mixture present in cytochrome C in capillary electrochromatography, in addition to the separation of six commercial peptides. We achieved an average plate count of over 1.5 million/m with the column of current study both for the digested protein components and commercial peptides using 70/30% v/v (acetonitrile/20 mM ammonium formate) at pH 6.5. In addition, the column resulted in baseline separation of all the peptides with very good resolution, enhanced peak capacity, and better retention time span. [ABSTRACT FROM AUTHOR]

A particle‐based stationary phase has been prepared for the separation of five synthetic peptides and a mixture containing tryptic digest of cytochrome C in liquid chromatography. Particles originating from silica monolith were differentially sedimented to obtain 1–2 μm particles. A stationary phase was achieved by the coating of poly(styrene‐methacrylic acid‐N‐phenylacrylamide) copolymer onto the particles via reversible addition‐fragmentation chain transfer polymerization reaction. Stainless steel column (30 cm long and 1 mm internal diameter) was packed with stationary phase. Very high separation efficiency (ca. 351 000 plates/m) was achieved for five commercial peptides with a percent relative standard deviation of less than 1%. Protocol for the synthesis and modification of silica monolith particles has been well optimized with a good reproducibility both in particle and pore size. The column resolved about 21 peptide components from a mixture containing tryptic digest of cytochrome C, under the elution conditions of acetonitrile/15 mM ammonium format (65/35 v/v%) with a flow rate of 28 μL/min. [ABSTRACT FROM AUTHOR]

This paper examines the colonial project of social control of the Pashtun body as seen through Foucauldian framework of biopower. This paper initiates debate into colonial health politics of NWFP and explores the biopolitical logic as to how the Pasthun subjectivities as medicalizable objects were constituted within the colonial missionary medicine discourses. It examines the ontological consequences of such constructions. It further aims to explore the co-constitution of colonial agents and the authority of the missionary doctor over the body. This paper delves into the myriad of strategies and sites of medical intervention, as hospital, medical camp, home, school, body, culture, race and gender. It takes up indepth analysis of the works of Dr. Pennell i.e. Mission Hospital Bannu and Life among Wild Tribes. The study proposes that the relations of colonial power with the Pashtun body as embedded in the medical missionary discourse were biopolitical in nature. [ABSTRACT FROM AUTHOR]

Renovated protocols for the synthesis and modification of sub-1 µm porous particles originating from silica monolith coupled with sophisticated packing procedures have made it possible to get excellent separation efficiency and the possibility for rapid analysis when dealing with five benzene derivatives in high-performance liquid chromatography. The catalyst-assisted binding of 4-chloromethylphenyl-isocynate and consequent reversible addition-fragmentation chain transfer (RAFT) polymerization enabled the attachment of uniform polymer film onto the silica particles. The column (1.0 mm ID × 300 mm length) packed with such particles resulted in supreme separation efficiency (256,200 plates/m) which is comparable to the separation efficiency of column packed with core shell particles. The optimum separation was obtained in 65/35 (v/v %) acetonitrile/water with 0.1% trifluoroacetic acid at a flow rate of 28 µL/min. Particle size reduction with increased pore size along with sophisticated packing protocol, partial monolithic architecture of the packed bed, and uniformly distributed polymer film are the beneficial features responsible for the improved chromatographic performance of the final stationary phase. [ABSTRACT FROM AUTHOR]

The sedimentation procedure has been adopted in production of ground silica monolith particles to improve chromatographic separation efficiency of the resultant phase. First, silica monolith particles have been successfully prepared in a large scale by a sol-gel process followed by grinding. The particles after calcination were separated by sedimentation into three zones using an Imhoff sedimentation cone. The particles of the bottom zone were derivatized with a C18 ligand and end-capped. The sedimentation process was found to not only eliminate troublesome minute particles but also narrow down the particle size distribution. The resultant phase was packed in glass lined stainless steel micro-columns. The average number of theoretical plates (N) of the columns for a test mixture was 47,000 and 29,300 for the 300 and 150 mm columns (1 mm internal diameter), corresponding to 157,000/m and 195,000/m, respectively. [ABSTRACT FROM AUTHOR]

• Atomic Orbital Search metaheuristic algorithm is used to extract solar parameters. • RMSE has been calculated using both frameworks used in the published literature. • Calculations have been performed for thirty published literature data. • AOS provides better performance compared to other advanced algorithms. In the available literature, there are several methods and techniques are employed to extract the unknown parameters of solar cell. The performance of the method used is validated on the basis of Root Mean Square Error (RMSE) value. This work aims to promote a decent basis for proper investigation and the implementation of an optimization algorithm to extract solar unknown parameters. In this work, the true value of RMSE is calculated for the single diode model of the RTC France solar cell using 30 different methods published in several literatures. The obtained results show that the approach of calculating RMSE is not precise in most of the published literature. The Atomic Orbital Search algorithm is proposed as a new metaheuristic optimisation method to extract the parameters of a single diode, double diode and three diode models for RTC France and PVM752 GaAs thin film solar cell. Last, the performance of the proposed algorithm is compared with other different optimisation algorithms. It is observed that the proposed algorithm gives best results with less RMSE as compared to other algorithms. This work intends to provide a solid foundation for thorough analysis and implementation of an optimization technique to extract unknown solar parameters. [ABSTRACT FROM AUTHOR]

The article explores on the clinical diagnostics of disease mechanisms and biomarker discovery of proteomic samples. It examines the separation of peptides in the open tubular capillary electrochromatography (OT-CEC) columns. It also cites the formulations of the polymerization mixtures in the polar monomer.

Sintering of ceramics is known to suffer from homogeneity issues (of phase, microstructure, etc.). The present work aims to provide a simple solution for the same via positioning the sample vertically during conventional sintering. Via vertical sintering, we present two different case studies (with doped-ZrO 2 and La 2 Ce 2 O 7 systems) and illustrate two distinct benefits; e.g., restricting the formation of an otherwise deleterious monoclinic phase in zirconia bodies, and ensuring uniform in-plane texture development on both sides of the ceramic. In each case, the issues observed in the horizontally placed ceramic have been explained in connection to the heat transfer in the ceramic body. Discrepancies in heat transfer resulted in variations in grain orientation and size (mean, median, and cumulative size distribution), eventually leading to different phase developments and texture. This small adjustment (of the positioning of ceramic bodies) may be beneficial at an industrial scale; especially with samples having a large length/diameter ratio. [Display omitted] • Crucial dependence of positioning of ceramic samples during conventional sintering. • Doped-ZrO 2 and La 2 Ce 2 O 7 ceramic was chosen for the case studies. • Vertical sintering resulting in uniform texture and control phase-purity. • Horizontal sintering depicted abundant monoclinic-ZrO 2 phases. • Discrepancies noted for in-plane texture of horizontally sintered La 2 Ce 2 O 7 ceramic. [ABSTRACT FROM AUTHOR]

A silica capillary of 50 μm internal diameter and 500 mm length (416 mm effective length) was chemically modified with 4-(trifluoromethoxy) phenyl isocyanate in the presence of dibutyl tin dichloride as catalyst. Sodium diethyl dithiocarbamate was reacted with the terminal halogen of the bound ligand to incorporate the initiator moiety, and in situ polymerization was performed using a monomer mixture of styrene, N-phenylacrylamide, and methacrylic acid. The resultant open tubular capillary column immobilized with the copolymer layer was used for the separation of tryptic digest of cytochrome C in capillary electrochromatography. The sample was well eluted and separated into many components. The elution patterns of tryptic digest of cytochrome C were studied with respect to pH and water content in the mobile phase. This preliminary study demonstrates that open tubular capillary electrochromatography columns with a modified copolymer layer composed of proper nonpolar and polar units fabricated by reversible addition-fragmentation transfer polymerization can be useful as separation media for proteomic analysis. [ABSTRACT FROM AUTHOR]

A ligand with a terminal halogen (4-chloromethylphenyl isocyanate) was chemically bound on the inner surface of pretreated silica capillary with 50 μm internal diameter and 58 cm total and 50 cm effective length in the presence of dibutyl tin dichloride as a catalyst through isocyanate-hydroxyl reaction. Attachment of initiator (sodium diethyl dithiocarbamate) to the bound ligand was carried out and followed by in situ polymerization. Reversible addition-fragmentation chain transfer polymerization was used for the immobilization of N-phenylacrylamide-styrene copolymer on the inner surface of capillary column. The resultant open tubular column showed excellent separation performance for derivatized saccharide isomers in capillary electrochromatography. d-Glucose was separated into α- and β-anomers while five structural isomers were separated for derivatized maltotriose with separation efficiency above one million theoretical plates per meter. The effects of pH and acetonitrile composition on the electrochromatographic performance of the derivatized saccharides were studied and the optimized elution condition was found to be 90:10 v/v% acetonitrile/30 mM sodium acetate at pH 6.6. UV absorption at 214 nm was used as detection mode in open tubular capillary electrochromatography separations. [ABSTRACT FROM AUTHOR]

Ground porous silica monolith particles with an average particle size of 2.34 μm and large pores (363 Å) exhibiting excellent chromatographic performance have been synthesized on a relatively large scale by a sophisticated sol-gel procedure. The particle size distribution was rather broad, and the d(0.1)/ d(0.9) ratio was 0.14. The resultant silica monolith particles were chemically modified with chlorodimethyloctadecylsilane and end-capped with a mixture of hexamethyldisilazane and chlorotrimethylsilane. Very good separation efficiency (185 000/m) and chromatographic resolution were achieved when the C18-bound phase was evaluated for a test mixture of five benzene derivatives after packing in a stainless-steel column (1.0 mm × 150 mm). The optimized elution conditions were found to be 70:30 v/v acetonitrile/water with 0.1% trifluoroacetic acid at a flow rate of 25 μL/min. The column was also evaluated for fast analysis at a flow rate of 100 μL/min, and all the five analytes were eluted within 3.5 min with reasonable efficiency (ca. 60 000/m) and resolution. The strategy of using particles with reduced particle size and large pores (363 Å) combined with C18 modification in addition to partial-monolithic architecture has resulted in a useful stationary phase (C18-bound silica monolith particles) of low production cost showing excellent chromatographic performance. [ABSTRACT FROM AUTHOR]

Highlights: [•] Catalytic isocyanate-hydroxyl reaction was incorporated to make initiator attached silica monolith particles. [•] RAFT polymerization on them yielded a new stationary phase of improved separation efficiency. [•] The number of column theoretical plates is better than that of any commercial HPLC or UHPLC column. [ABSTRACT FROM AUTHOR]

Highlights: [•] A huge amount of recent information is introduced on a variety of open tubular columns. [•] The studies of excellent chromatographic performances of open tubular columns are included. [•] Some guidelines are suggested for realization of open tubular columns of better performances. [Copyright &y& Elsevier]

Highlights: [•] Partially sub-2μm silica monolith particles with rather large pores were prepared. [•] Polystyrene bound monolith particles were prepared by RAFT polymerization. [•] The resultant phase showed very good efficiencies. [Copyright &y& Elsevier]

Abstract: Molecular imprinted polymer (MIP) techniques have been increasingly used in a variety of fields including chromatography, sample pretreatment, purification, sensors, drug delivery, and catalysts, etc. MIP is a specific artificial receptor that shows favored affinity to the template molecule. The cavities of the template are produced by carrying out polymerization of a reaction mixture followed by eliminating the template molecules by washing. Various forms of MIP materials have been prepared for diverse applications including irregularly ground particles, regular spherical particles, nanoparticles, monoliths in a stainless steel or capillary column, open tubular layers in capillaries, membranes, surface attached thin layers, and composites, etc. When an enantiomer is used as the template, then the resulting MIP can show capability of enantiomeric recognition between the pair of enantiomers. In this review, progresses in applications of enantio-selective recognition by MIPs will be critically reviewed for the recent period since 2007. [Copyright &y& Elsevier]

A molecularly imprinting polymer (MIP) was synthesized for Basic Blue 3 dye and applied to wastewater for the adsorption of a target template. The MIPs were synthesized by bulk polymerization using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA). Basic Blue 3 dye (BB-3), 2,2′-azobisisobutyronitrile (AIBN) and methanol were used as a functional monomer, cross linker, template, initiator and porogenic solvent, respectively, while non-imprinting polymers (NIP) were synthesized by the same procedure but without template molecules. The contact time was 25 min for the adsorption of BB-3 dye from 10 mL of spiked solution using 25 mg polymer. The adsorption of dye (BB-3) on the MIP followed the pseudo-second order kinetic (k2 = 0.0079 mg·g−1·min−1), and it was according to the Langmuir isotherm, with maximum adsorption capacities of 78.13, 85.4 and 99.0 mg·g−1 of the MIP at 283 K, 298 K and 313 K, respectively and 7 mg·g−1 for the NIP. The negative values of ΔG° indicate that the removal of dye by the molecularly imprinting polymer and non-imprinting polymer is spontaneous, and the positive values of ΔH° and ΔS° indicate that the process is endothermic and occurred with the increase of randomness. The selectivity of the MIP for BB-3 dye was investigated in the presence of structurally similar as well as different dyes, but the MIP showed higher selectivity than the NIP. The imprinted polymer showed 96% rebinding capacity at 313 K towards the template, and the calculated imprinted factor and Kd value were 10.73 and 2.62, respectively. In this work, the MIP showed a greater potential of selectivity for the template from wastewater relative to the closely similar compounds. [ABSTRACT FROM AUTHOR]

The article discussed a study which focused on the synthesis of silica monolith particles. Topics discussed include chemical modification of the silica monolith particles using C-18 alkyl ligand, particle size distribution of the silica monolith particles, and analysis of the molecules using high performance liquid chromatography (HPLC).

• Thermophysical properties measured for textured and un-textured La 2 Ce 2 O 7 ceramics. • Texturing took place along the closed packed 〈111〉 as well as measurement direction. • Thermal conductivity (1.68 W/mK), expansion (15.2 × 10−6/ °C) noted within 600–1200 °C. • Thermal expansion and conductivity follows a texture-insensitive trend, in general. Cubic crystals are generally known to be isotropic with respect to second rank property tensor and hence expected to show no change in relation to the measurements involving such properties. In a stark contrast, fluorite (F m 3 ¯ m) cubic textured La 2 Ce 2 O 7 ceramic depicted a strong dependence with electrical resistivity in our recent study. This motivated us to examine the effect of texture on other second rank tensor properties, namely, thermal conductivity (TC) and thermal expansion coefficient (TEC). The texturing in La 2 Ce 2 O 7 ceramic took place along the closest packed 〈111〉 direction. The thermophysical properties (TC and TEC), measured for both textured and un-textured ceramics, depicted no special relevance of texture; reveling a fundamental difference between electron conduction and thermal conduction via phonons. The dependence of thermophysical properties on the cubic systems seems to extend beyond symmetry; a number of such factors are highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

The Class-II AP-endonuclease (XthA) is a mycobacterial DNA base excision repair (BER) pathway enzyme that functions in the initial steps. It acts on DNA substrates that contain abasic sites to create nicks with 3′-hydroxyl (OH) and 5′-deoxyribose phosphate (5′-dRP) moieties. The NAD+-dependent DNA ligase (LigA) is the terminal player in mycobacterial BER and seals such nicks efficiently. Here, we demonstrate that the Mtbβ-clamp-MtbXthA complex that exists in the initial steps of BER engages with MtbLigA to form a novel tri-component BER complex. Size exclusion chromatography (SEC) experiments analysis show that the three proteins interact with equimolar stoichiometry. Small angle X-ray scattering (SAXS) analysis and associated studies reveal that the apo tri-component BER-complex adopts an extended conformation where MtbXthA is sandwiched between the Mtbβ-clamp and MtbLigA. The studies support that in the apo -complex MtbXthA binds subsite-I of Mtbβ-clamp through 239 QLRFPKK 245 motif and to MtbLigA by 104 DGQPSWSGKP 113 motif simultaneously. However, the complex adopts a less-extended conformation in the presence of substrate DNA, where MtbXthA interactions switch from predominantly subsite-I to subsite-II of the Mtbβ-clamp. Overall, the novel tri-component complex prevents futile ligation activity of MtbLigA on the product of MtbXthA and ensures forward progression of the pathway and productive mycobacterial BER interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly efficient adsorbent was prepared for the removal of carbofuran and imidacloprid pesticides from wastewater. The silica monolith anchored graphene oxide composite was synthesized by the modified Fischer esterification protocol. The composite showed improved adsorption capacity for the removal of pesticides from wastewater. Graphene oxide was synthesized using the modified Hummer's method, while the silica monolith was prepared via sol–gel method. The composite was characterized via X-ray diffraction, Fourier transform infra-red, Brunauer Emmett and Teller (BET/BJH) analysis, zeta potential, and FESEM imaging. Different adsorption parameters such as pH, contact time, adsorbate and adsorbent concentration, and temperature were optimized for the adsorption of pesticides. The equilibrium and kinetic models were applied to the adsorption process of the pesticides. Qe of the composite as found to be 342.46 mg g−1 for imidacloprid and 37.15 mg g−1 for carbofuran. The adsorption process followed the pseudo 2nd order kinetic model for carbofuran (R2~0.9971) and imidacloprid (R2~0.9967). The Freundlich isotherm best fitted to the adsorption data of the pesticides with R2 value of 0.9956 for carbofuran and 0.95 for imidacloprid. The resultant adsorbent/composite material came out with very good results for the removal of pesticides. [ABSTRACT FROM AUTHOR]

The ligand 2,6-bis(E)-4-methylbenzylidine)-cyclohexan-1-one sensor has been synthesized as a fluorescence-on sensor/probe for the trace level detection of chromium III ion. The synthesized ligand was characterized by FTIR, 1H-NMR spectroscopy, and fluorimetery. The sensor exhibited an ultra-selective response to chromium among the tested heavy metal ions. Different parameters were optimized like pH, effect of concentration of sensor C, metal ion and contact time. The binding stoichiometry of C:Cr3+ was calculated to be 2:1 (Job's plot) with a significantly low detection limit of 2.3 × 10− 9 M. Sensor C were practically employed for detection of chromium in spiked water samples. [ABSTRACT FROM AUTHOR]

Molecular imprinted polymer is an artificial receptor made by imprinting molecules of a template in a polymer matrix followed by removing the template molecules via thorough washing to give the permanent template grooves. They show favored affinity to the template molecule compared to other molecules, and this property is the basic driving force for such diverse application of this techniques. Such techniques have been increasingly employed in a wide scope of applications such as chromatography, sample pretreatment, purification, catalysts, sensors, and drug delivery, etc., mostly in bioanalytical areas. A major part of them is related to development of new stationary phases and their application in chromatography and sample pretreatment. Embodiments of molecular imprinted polymer materials have been carried out in a variety of forms such as irregularly ground particles, regular spherical particles, nanoparticles, monoliths in a stainless steel or capillary column, open tubular layers in capillaries, surface attached thin layers, membranes, and composites, etc. There have been numerous review articles on molecular imprinted polymer issues. In this special review, the reviews in recent ca. 10 years will be categorized into several subgroups according to specified topics in separation science, and each review in each subgroup will be introduced in the order of date with brief summaries and comments on new developments and different scopes of prospects. Brief summaries of each categories and conclusive future perspectives are also given. [ABSTRACT FROM AUTHOR]

[Display omitted] • The simple, fast and highly sensitive method for the determination of pinoxaden is based on fluorescence measurement of the Fe(III) based coordination complex of pinoxaden in the basic medium at 337 nm. • The signaling product is kinetically stable at room temperature having maximum fluorescence intensity with 0.2 µg mL−1 of Fe(III) at pH 9. • The complex shows a linear concentration range from 1 × 10−4,-1 × 10−3 µg mL−1 with a coefficient of determination R2 = 0.9917. • Density functional theory simulations shows stronger interaction energy (-1.11 eV) of Fe(III) ion with the pinoxaden. • The proposed approach is applied to quantify pinoxaden in the formulation and real agricultural and environmental samples and shows excellent recovery. Keeping in view the toxicity of pesticides, development of analytical methods for their determination in environmental samples is the need of the day. Herein, a simple, fast and sensitive method for the determination of pinoxaden has been described. The kinetically stable, Fe(III) based complex of pinoxaden was formed at room temperature showing maximum fluorescence intensity at 337 nm with 0.2 µg mL−1 of Fe(III) at pH 9. The complex shows a linear response in the concentration range of 1 × 10−4-1 × 10−3 µg mL−1 with a coefficient of determination R2 = 0.9917, limit of detection and limit of quantification of 8.1 × 10−5 and 2.4 × 10−4 µg mL−1, respectively, and relative standard deviation and maximum matrix effect of 0.021% and 2.13%. Density functional theory simulations were used to understand the nature of Fe(III) based complex of pinoxaden. The larger negative interaction energy of −1.11 eV evince that the Fe(III) strongly coordinated with the N-atom shared by oxadiazopine ring and the pyrazole ring and the O atom of –C O group of side chain, which are consistent with the experimental results. Interference study shows that among the metal ions studied, only Cu(II), Co(II) and Pb(II) show reasonable interference effect. The proposed approach was applied to quantify pinoxaden in the formulation and real agricultural and environmental samples. The results indicate excellent recovery in the range of 89.44 ± 1.38–97.51 ± 2.62 % for wheat, barley, water and soil samples. In soil samples no residue was quantified while in the wheat and barley samples the residue found was below the maximum residue limit. Under optimized experimental conditions, the proposed method was found to be simple, fast, reasonably interference free and has trace level sensitivity. The method was found to be comparable and even superior to some literature methods for determination of pinoxaden in complex matrices. [ABSTRACT FROM AUTHOR]

Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter decontamination issues. Metal nanoparticles are considered the most effective heterogeneous photocatalysts for photodegradation of organic pollutants, but neat nanoparticles agglomerate in the reaction medium and display less photocatalytic efficiency. Herein, silica monolith particles (SiO2) were synthesized and utilized as a support medium for the synthesis of SnO2 nanoparticles to retard their agglomeration. Silica-supported tin oxide nanoparticles (SnO2/SiO2 NPs) and neat tin oxide nanoparticles (SnO2 NPs) were prepared through chemical reduction method and characterized by AFM, SEM, TEM, EDX and mapping, XRD, FTIR and zeta sizer. Morphological and mapping analyses revealed that SiO2 increases the surface area of SnO2 NPs and magnificently enhances their photocatalytic activity. The neat SnO2 NPs are highly agglomerated and hence show less photocatalytic activity. XRD and FTIR analyses confirm the synthesis of SnO2 NPs. The neat SnO2 NPs have a PDI of 0.51, which reveal much variation in the particles' size and have a surface charge of −11.2 ± 0.87 mV, which is not enough for the NPs' repulsion in suspended form and hence are agglomerated. The SnO2/SiO2 NPs degraded about 94.58% and 93.73% orange II (O II) dye while SnO2 NPs degraded 65.93% and 46.11% dye within 30 min irradiation under UV and visible light respectively. The enhanced photocatalytic activity of SnO2/SiO2 NPs is due to the synergistic effect of rapid adsorption followed by drastic photodegradation of dye. The SnO2/SiO2 NPs are much more sustainable than SnO2 NPs due to easy recycling and washing and the recovered SnO2/SiO2 NPs degraded about 83.38% of dye while SnO2 degraded 21.91% within 30 min. In addition, the density functional theory (DFT) calculations show that the SnO2/SiO2 NPs have greater adsorption capacity then pristine SiO2 and SnO2 surfaces, having shorter binding distances, a larger Eads value (4.29 eV) and a larger reduction in band gap. [ABSTRACT FROM AUTHOR]

The performance of a 100 um i.d. open tubular column modified with linear co-polymer chains has been explored under low pressure operating conditions. A 512 mm fused-silica capillary was reacted with 3-chloropropyl isocyanate followed by sodium diethyldithiocarbamate. A copolymer layer was then immobilized on the inner surface via reversible addition-fragmentation transfer polymerization of styrene, methacrylic acid and N-phenylacrylamide. The thickness of the polymer layer was ca 1.5 µm. The column was evaluated for the separation of a mixture composed of three peptides (Trp-Gly, angiotensin I, bradykinin). The number of theoretical plates (N) as high as 72,100 plates/column (corresponding to 140,800/m, 7.10 µm plate height) was achieved. The column to column and day to day reproducibility of our columns was found better than 2.1%. For comparison purpose, similar chromatographic data for a selected analyte was also obtained with a commercial microcolumn of 0.5 mm id packed with a conventional C18 phase (5 µm), and 17 µm was the plate height obtained at the optimum flow rate. The van Deemter plots and kinetic plots were also obtained for comparison between our open tubular capillary column and the commercial packed column of a narrow id. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To understand various sources of stress and assess coping strategies among medical students of Al-Nafees Medical College, Islamabad. STUDY DESIGN: A descriptive cross sectional observational study. PLACE AND DURATION: The survey was carried out on the MBBS students of Al-Nafees Medical College Islamabad from 11th May, 2015 to 3rd July, 2015. METHODOLOGY: The undergraduate MBBS students of Al-Nafees Medical College were approached in the study. The socio- demographic determinants included the class of the participants, their age, gender, country of birth, their degree before MBBS and parents' educational level. The objectives of the study intended to determine the prevalence of stress among medical students, to identify various stressors experienced by undergraduate medical students during their graduation and assessing medical students' coping strategies for various stressors during their undergraduate medical education. The structured questionnaire comprised on closed-ended questions based on the specified objectives mentioned above. RESULTS: The response rate came out to be 91%. The prevalence of distressed students came out to be 52.5%. Regarding the distribution of stressors according to students' responses, it was found that the top stressor considered by majority of the students was having too much course content to be learnt. Students also considered having shortage of time, difficulty in retaining course content and taking frequent examination as potent stressors. The majority of the students (above 80%) use religion as a coping response while about 55% of the students approach their parents for the use of emotional support when stressed. CONCLUSION: The study revealed that the prevalence of the stress is quite high amongst the medical students. The top stressors in our cohort were mostly related to academic issues and poor time management skills. Majority of the students cope with stress using religion while the other coping strategy used by distressed students includes self-blame, venting of emotions through anger and frustration and distracting themselves by logging on to facebook. [ABSTRACT FROM AUTHOR]

Objective: To assess awareness, attitudes and opinions regarding bioethical issues among graduate students and faculty/researchers of universities in Lahore, Pakistan. Methodology: A questionnaire consisting of 20 questions was designed and sent to 700 students and faculty members/researchers of 14 academic departments/research institutions of seven universities in Lahore, Pakistan. Data were analyzed with descriptive statistics using SPSS 16.0. Results: We obtained responses from 87% (614/700) participants. The sample populations appeared receptive to latest developments in science and technology; and were optimistic that such developments will have positive effect on their lives. On average almost 90% of the respondents were familiar with the term "bioethics"; 75.4% of the respondents desired that bioethics should be taught regularly in the classes. However, students of two important disciplines of knowledge i.e law and Islamic studies had awareness levels of only 43% and '0'% respectively regarding the term bioethics. A vast majority of the respondents were not satisfied with the state laws, policies, rules, regulations and institutions concerned with bioethical issues. The survey indicated that cloning (27.2%), abortion (24.6%) and organ donation (13.2%) are regarded as the most important bioethical issues, probably for specific reasons of the glamour attached to the technology, moral connotations and the hype created by media respectively. Conclusion: Educated youth in general have positive attitude towards S&T and its effect on their lives. Awareness level among students and faculty of life sciences is very high; however it is dismally low among students of Law and Islamic studies. The results of this survey does not necessarily mirror the awareness level, attitudes and opinions in the society at large since literacy level among the masses is low (57%) and prevalence of higher levels of education is even lower. [ABSTRACT FROM AUTHOR]