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Irradiation of materials by high energy (∼MeV) ions causes intense electronic excitations through inelastic transfer of energy that significantly modifies physicochemical properties. We report the effect of 100 MeV Ag ion irradiation and resultant localized (∼few nm) thermal spike on vertically oriented TiO2 nanorods (∼100 nm width) towards tailoring their structural and electronic properties. Rapid quenching of the thermal spike induced molten state within ∼0.5 picosecond results in a distortion in the crystalline structure that increases with increasing fluences (ions per cm2). Microstructural investigations reveal ion track formation along with a corrugated surface of the nanorods. The thermal spike simulation validates the experimental observation of the ion track dimension (∼10 nm diameter) and melting of the nanorods. The optical absorption study shows direct bandgap values of 3.11 eV (pristine) and 3.23 eV (5 × 1012 ions per cm2) and an indirect bandgap value of 3.10 eV for the highest fluence (5 × 1013 ions per cm2). First principles electronic structure calculations corroborate the direct-to-indirect transition that is attributed to the structural distortion at the highest fluence. This work presents a unique technique to selectively tune the properties of nanorods for versatile applications.

Financial technology (Fintech) refers to software and other modern technologies to provide automated and improved financial services. We surveyed to examine the factors influencing the adoption of Fintech in the financial institutions of Bangladesh with the help of the Unified Theory of Acceptance and Use of Technology (UTAUT) model and selected eight influencing factors. Before collecting data, a well-structured face-to-face survey was arranged. Structural Equation Modeling (SEM) with Generalized Least Squares method has been used to analyze the primary data gathered from 265 employees. The results verified that effort expectancy, social influence, facilitating condition, perceived reliability, added value positively influence the behavior intention to adopt Fintech. Additionally, the age of the respondents has a significant moderating effect on almost all the factors on Fintech adoption.

A series of charge compensated Ga–V co-doped TiO2 samples (Ti(1-x)(Ga0.5V0.5)xO2) have been synthesized by a modified sol-gel process. X-ray diffraction pattern shows that the anatase to rutile (A→R) onset temperature (TO) shifts to a higher temperature, whereas the complete phase transformation temperature (TC) shifts to a low-temperature region as compared to pure TiO2, due to Ga–V incorporation. Ga–V co-doping helps in the transformation of some smaller sized Ti4+ to a relatively larger Ti3+. In the anatase phase, oxygen content also increases with increasing doping concentration, which along with the larger size of Ti3+ results in lattice expansion and thereby delays the TO. In the rutile phase, oxygen vacancy increases with increasing doping concentration, which results in lattice contraction and accelerates phase transition. Grain growth process is hindered in the anatase phase (crystallites size reduces from ~15 nm (x = 0.00) to 8 nm (0.10)), whereas it is accelerated in the rutile phase as compared to pure TiO2. In both phases bandgap (Eg) reduces to the visible light region (anatase: Eg = 3.16 eV (x = 0.00) to 2.19 eV (x = 0.10) and rutile: 3.08 eV (x = 0.00) to 2.18 eV (x = 0.10)) in all co-doped samples. The tail of the absorption edge reveals lattice distortion and increase of Urbach energy proofs the same due to co-doping. All these changes (grain growth, phase transition, and optical properties) are due to lattice distortion created by the combined effect of substitution, interstitials, and oxygen vacancies due to Ga–V incorporation in TiO2.

The discovery of aggregation-induced emission (AIE) phenomenon, significantly altered the understanding of the scientific world about the luminophore aggregation. Polymers with AIE features have recently emerged as promising materials with wide range of applications in optoelectronics devices, chemosensors, bioimaging, cancer theranostics and drug delivery. By introducing the AIE active molecule into the polymer structure, novel materials encompassing the characteristics properties of both the functional materials such as excellent brightness, versatile structure modification, high biocompatibility, exceptional stability and facile processability are achieved. This chapter presents the advances in synthetic design as well as potential biological applications of AIE active polymers, beginning with a brief introduction to the AIE phenomenon. The versatile synthetic route, easier functionalization, and light up feature of the AIE active polymers offer direct visualization of the physiological processes within or outside the living organisms. This chapter also precisely describes the photodynamic therapy/photothermal therapy (PDT/PTT) with up-to-date advancement of AIE active polymer and their emerging applications in biomedical field. The AIE active Photosensitizers (PSs) are much more efficient in singlet oxygen (

Irradiation of materials by high energy (∼MeV) ions causes intense electronic excitations through inelastic transfer of energy that significantly modifies physicochemical properties. We report the effect of 100 MeV Ag ion irradiation and resultant localized (∼few nm) thermal spike on vertically oriented TiO

Ultrathin g-C3N4 (g-CN) nanosheets are prepared by a two-step thermal exfoliation process in an air atmosphere. X-ray diffraction pattern (XRD) shows that ultrathin g-CN nanosheets have the same crystal structure as that of the bulk g-CN with a slight shift in the peak positions due to the reduction of sheet thickness. Field emission scanning electron microscope (FESEM) images show that the bulk g-CN is converted into ultrathin g-CN nanosheets due to thermal oxidation in an atmosphere, which increases the number of reactive active sites for water splitting. Due to a reduction in sheet thickness of g-CN, quantum confinement happened and thereby increase the bandgap from 2.88 (bulk g-CN) eV to 3.10 eV (ultrathin g-CN). Steady-state photoluminescence (PL) shows a blue shift, and time-resolve photoluminescence (TRPL) shows that the average lifetime of photogenerated charge carrier increases when bulk g-CN is converted into ultrathin g-CN nanosheets. Enhancement in photoelectrochemical performance is observed in ultrathin g-CN nanosheets compared to bulk g-CN due to the increased average lifetime of photogenerated charge carriers and a large number of reactive active sites.

The discovery of aggregation-induced emission (AIE) phenomenon, significantly altered the understanding of the scientific world about the luminophore aggregation. Polymers with AIE features have recently emerged as promising materials with wide range of applications in optoelectronics devices, chemosensors, bioimaging, cancer theranostics and drug delivery. By introducing the AIE active molecule into the polymer structure, novel materials encompassing the characteristics properties of both the functional materials such as excellent brightness, versatile structure modification, high biocompatibility, exceptional stability and facile processability are achieved. This chapter presents the advances in synthetic design as well as potential biological applications of AIE active polymers, beginning with a brief introduction to the AIE phenomenon. The versatile synthetic route, easier functionalization, and light up feature of the AIE active polymers offer direct visualization of the physiological processes within or outside the living organisms. This chapter also precisely describes the photodynamic therapy/photothermal therapy (PDT/PTT) with up-to-date advancement of AIE active polymer and their emerging applications in biomedical field. The AIE active Photosensitizers (PSs) are much more efficient in singlet oxygen (1O2) production than their small molecule AIE active PSs due to their enhanced inter system crossing (ISC) process and improved light-harvesting ability. Additionally, the present chapter aims to focus on all recent AIE active polymers for drug screening and drug delivery. The AIE active polymer often shows decent drug loading capacity, high stability and good biocompatibility comprising image guided drug monitoring features. Lastly, the concluding discussion reveals the future prospective of the AIE active polymers.

Uncompensated Ga-V co-doped TiO2 samples have been prepared by modified sol-gel process. Inhibition of phase transition due to co-doping is confirmed by X-ray diffraction measurement. Activation of phase transition increases from 120 kJ/mol (x = 0) to 240 kJ/mol (x = 0.046) due to Ga-V incorporation. In anatase phase, lattice constant increases by the effect of Ga3+ interstitials. This results in inhibition of phase transition. Anatase phase becomes stable up to ~ 650 °C in co-doped sample whereas for pure TiO2 phase transition starts in between 450 and 500 °C. High-resolution transmission electron microscope image shows particle size decreases in anatase phase due to co-doping. Increasing strain due to Ga-V incorporation results in reducing crystallite size. Brunauer–Emmett–Teller analysis shows that surface increases from 4.55 m2/g (pure TiO2) to 96.53 m2/g (x = 0.046) by Ga-V incorporation. In rutile phase, grain growth process is enhanced mainly due to the effect of Vanadium and particles show a rod-like structure with majority {110} facets. Bandgap decreases in both phases and reduced to visible light region. For charge balance in uncompensated Ga-V co-doped sample, structural distortion created in the lattice by combining effect of substitution, interstitials and oxygen vacancies, which results in stabilization of anatase phase and reducing of bandgap.

Pure and V/Ga doped TiO2 nanoparticles are prepared by the modified sol-gel process and are investigated using TEM, XRD, Raman spectroscopy and DRS techniques. Crystallites size decreased in doped ...

The structural, dielectric and ferroelectric properties of lead-free (Na0.5-xKxBi0.5-xLax)TiO3 (0 ≤ x ≤ 0.12) powders synthesized by modified sol-gel method was investigated. Rietveld refinement of synchrotron x-ray diffraction data confirms single phase rhombohedral crystal structure with R3c space group for all the compositions and anti-phase (a-a-a-) octahedral tilting angle decreased with increase in composition. Homogeneity and elemental proportions were confirmed by Energy dispersive x-ray spectrometry. The temperature-dependent dielectric study has shown two diffuse type of dielectric anomaly for all the samples, due to A-site disorder in the lattice, which has been assigned to two-phase transitions: ferroelectric to anti-ferroelectric and anti-ferroelectric to the paraelectric phase transition. Thermal stability range of dielectric constant increases from ~100 to 220 °C as a function of composition. Stable dielectric constant first increases from 1557 ± 10% for x = 0 compositions and highest for x = 0.06 sample with emid ~ 2508 ± 10% of the temperature range ~180–340 °C, and after that decreases to 1608 ± 10% for x = 0.12, but remain higher than the x = 0 composition. Ferroelectric measurements have shown monotonously decreasing coercive field as a function of the composition due to decrease in the average grain size, confirmed by microstructural studies using field emission scanning electron microscope. An exponential increase in the energy storage efficiency from ~ 17% to 87% as a function of composition have also observed. These types of materials, with the high stable dielectric constant (er) and low loss (tanδ), have a vast scope in the field of the thermally stable dielectric constant materials and energy storage applications.

CeO2 has a robust cubic fluorite face centered cubic (f.c.c.) structure. However, substitution in CeO2 can introduce lattice defects, tune optical properties and generate different functionalities. The oxidation state of a substituent triggers a Ce4+→Ce3+ transformation without destroying the structure but modifies the structure by generating defects. These structural changes should affect physical properties such as mechanical hardness along with electrical, optical and other properties. Mn substitution results in considerable changes in lattice parameters. Optical properties are affected. It is the valence state and ionic radius of the substituent which dominate the structural, vibrational and optoelectronic properties. Analysis reveals contraction of unit cell and increase in lattice strain affecting the hardness of the material. Microhardness studies show Indentation Size Effect with dominant plastic deformation.

Designing a photocatalyst material with reduced recombination of photogenerated charges is one of the most important aspects of hydrogen generation through solar water splitting. Here, we report hydrogen generation using the TiO2/ultrathin g-C3N4 (U-g-CN) heterostructure fabricated using a unique in situ thermal exfoliation process. Multilayer g-CN is converted into U-g-CN having a high surface (∼190 m2/g) area by calcination at ∼550 °C through oxygen-induced exfoliation, which also forms a robust heterostructure with TiO2. In addition, the presence of g-CN also inhibits further growth of TiO2 nanoparticles, thereby retaining a high specific surface area. The presence of U-g-CN causes a redshift (∼0.13 eV) in the absorption edge of heterostructure compared to that of bare TiO2, which extends the light absorption capability. Addition of 40 wt. % of multilayer g-CN to TiO2 shows an enhanced H2 evolution rate, which is ∼15 times and ∼4 times higher compared to that of bare TiO2 and U-g-CN, respectively. Photoluminescence (PL) and time-resolved PL (TRPL) studies indicate a reduced recombination rate of photogenerated charge carriers with an increase in the average lifetime from 10.53 (TiO2) to 13.32 ns (TiO2/U-g-CN40). The interfacial charge transport characteristics studied through impedance spectroscopy reveal a reduced charge transfer resistance at the semiconductor–electrolyte interface, which facilitates faster charge separation due to the heterostructure formation. The band edge positions are estimated through flatband potential from the Mott–Schottky measurements and optical absorption data, indicating a type-II heterojunction. More light absorption and enhanced separation of photogenerated charges at the heterojunction interface lead to better photocatalytic H2 generation.

The anatase to rutile phase transition of TiO 2 which normally occurs at 750 °C, is reduced to temperatures below 600 °C by vanadium doping. The structural transformation is observed by a systematic study in the temperature range from 450 °C to 750 °C. The introduction of vanadium in rutile lattice is found to have impact on lattice parameters and particle size. This substitution also helps to reduce the bandgap of rutile TiO 2 to 1.76 eV from 3.04 eV upon 6 at% of vanadium doping. Vanadium induces additional donor level in forbidden region. XANES study confirms that vanadium is in mixed valence state of V 4+ and V 5+ and concentration of V 4+ increases with increasing doping amount and in the band gap region donor level due to V 4+ takes deeper position than V 5+ . As a result, the effective band gap decreases with increasing vanadium concentration. Anharmonicity of vibrational modes systimatically increases which indicates increasing phonon-phonon interaction with increasing doping concentration.

Powders with compositions Ti(1−x)SixO2 (where 0 ≤ x ≤ 0.25) were prepared to systematically study the effects of Si doping on anatase to rutile phase transformation. Samples were synthesized using a modified sol–gel route and were heat treated at various temperature in 450–950 °C range. XRD, Raman Spectroscopy, UV–vis spectroscopy, SEM, TEM were used to study the effects of dopant concentration and heat-treatments on the crystal structure, crystallite size and particle size. Rutile phase was found to occur only above a critical crystallite size. Si doping was found to delay the onset of anatase to rutile phase transformation from 500 °C (for composition x = 0) to 800 °C (for x = 0.25) through the lattice strain and crystallize size modification. Interplay between the average crystallite sizes, lattice strain, annealing temperature, and their effect on phase transition are discussed in terms of Si incorporation in lattice.

Background: Marginal continuty is very important for the longevity of restoration .The junction between the cemented restoration and the tooth is always a potential site for recurrent caries, gingivitis and periodontitis and ultimately failure of crown as well as teeth. Hypothesis: Marginal continuity for shoulder finish line for anterior teeth and chamfer for posterior teeth are equally effective. Objectives: To evaluate the marginal continuity of metal crown. Methods: Thirty extracted human teeth were prepared with shoulder margin (group-A) and another thirty teeth were prepared with chamfer (group-B) as methodically. Metal crown was fabricated by lost wax technique of casting procedure. All of the crowns (both group-A and group-B) were cemented by glass inomer luting cement. Each crown was sectioned in faciolingual direction at the midpoint of each surface by slow speed isomet saw. The sectioned crowns were examined under sreriomicroscope for measurement of marginal continuty. Data were collected on the basis of marginal continuty of each crown was compared. Collected data were processed and analyzed using SPSS (Statistical Package for Social Service) version 12. Results: The frequency distribution of marginal continuity were statistically non significant between two groups. Conclusion: All metal crowns had greater continued margin than discontinued margin. Update Dent. Coll. j: 2017; 7 (1): 26-29

The development of a new naphthalene appended naphthalimide derivative (NMI) with aggregation-induced enhanced emission (AIEE) property for the sensitive detection of 4-nitroaniline (4-NA) in aqueous media is presented here. The newly designed naphthalimide AIEEgen has an exceptional blue-shifted condensed state emission that is devoid of any receptor site, accomplished ultrasensitive detection of 4-NA, which is one of the broad-spectrum pesticides that belong to the class III toxic chemical, at parts per billion level (LOD/36 ppb, Ksv =4.1×104 m-1 ) in water with excellent selectivity even in the presence of potentially competing aliphatic and aromatic amines. The reported probe is the first of its kind, demonstrating major advantages of receptor-free inner filter effect (IFE) mechanism for the sensitive detection of 4-NA using an AIEEgenic probe. Excellent sensitivity for 4-NA is also achieved on paper-based test-strip for low-cost on-site detection.

A study of structure, morphology, and dielectric/complex impedance spectroscopy of lead-free 0.94(Na0.50Bi0.50)Ti0.95V0.05O3-0.06BaTiO3 ceramics, prepared by a modified sol-gel process, is explored. Rietveld refinement of x-ray diffraction confirmed the rhombohedralR3c phase. Temperature-dependent dielectric studies showed the antiferroelectric to paraelectric phase transition at a temperature, Tm∼ 287 °C. Complex impedance spectroscopy confirmed that the conductivity was found to increase from 1.8×10−8 Ω−1cm-1 (at 240 °C) to ∼2.6×10−5 Ω−1cm−1 (at 380 °C) with increasing temperature.

Vanadium substituted TiO2 samples are prepared by modified sol-gel process. X-ray diffraction (XRD) pattern and Raman spectra for all the samples reveal pure tetragonal phases of TiO2. Rutile percentage calculated from XRD pattern and Raman spectra follow a similar trend and signify that vanadium substitution promotes phase transformation from anatase to rutile. Due to aliovalent V substitution, donor levels are formed in the bandgap which is responsible for bandgap reduction.

Ce0.975A0.025O2 (A=Co, Ni) was synthesized using sol-gel method. X-ray diffraction (XRD), UV-Vis and Raman spectroscopy are employed to evaluate structural, optoelectronic and vibrational properties of samples. XRD and Raman analysis confirms substitution of Co and Ni in CeO2 host matrix. It is observed that Co doping cause more strain and structural disorder than Ni doping in CeO2. This is also reflected from crystallite size of samples. A broad Raman band emerges at ∼540-650 cm-1 indicating increase in oxygen vacancies with doping. X-ray absorption near edge structure (XANES) analysis estimates oxygen vacancies and valance state of Ce (Ce3+/Ce4+) in CeO2.

Here we present a simple and effective way of bandgap tuning by V-substitution in TiO 2 . The nanoparticles of Ti (1-x) V x O 2 (for 0≤ x ≤0.09) were prepared by controlled and simplified sol-gel method. The pure anatase phase of TiO 2 was confirmed by X-ray diffraction and Raman spectroscopy. Debye-scherrer formula and Williamson-Hall plot give crystallite size decreases from 10.8 to 8.2 nm when strain increases from 0.019 to 0.027 for x =0 to x =0.09. Rietveld refinement show the systematic change in crystal structure with the amount of V-substitutions. Raman shift and broadening of FWHM of first E g (145.52 cm −1 ) mode observed in Raman spectroscopy follow interestingly the similar and correlated observation with XRD outcomes. FESEM and UHRTEM represent pictorial view of the morphology of the nanoparticles with information about different micro-agglomerations and crystallinity. The oxidation states and local environment of elements in nanoparticles were studied using XANES. V-substitution in TiO 2 shows band gap moderation: band gap decreases gradually with substitution from 3.06–2.02 eV as concentration of V increases from x =0.0 to 0.09. This extends the application of TiO 2 in UV as well as visible light whereas the application of pure TiO 2 is limited in only UV region. The results of SEM, XRD, Raman spectroscopy and UV-vis spectroscopy are correlated well with lattice distortion and the lattice distortion gives the Urbach energy. We reach to the conclusion that the effective bandgap decreases may be due to creation of impurity energy levels or Urbach energy tails just above valance band and below conduction band.

CeO2 has cubic fluorite structure which is modified due to oxygen content as well as external substituents. The oxidation state of Ce plays an important role in strain and related physical properties. Ce3+ being larger in size than the Ce4+ ion, one expects a change in band structure due to changes in bond length; substitution of Ce4+ by Co2+ in sol–gel prepared, homogeneous, single-phase Ce1−xCoxO2 (x ≤ 10) nanopowders. The lower valence states of Co2+ induces oxygen vacancies which transforms some Ce4+ to Ce3+. A careful study of oxygen vacancies, strain, bond length and related band structure changes, have been targeted in this study. The possibility of phonon participation in electronic transition has been discussed using Tauc plot. Ce3+ forms defect states, between valence and conduction bands. Lattice parameters decrease, but strain increases with substitution.

The pure and V-Nd co-doped TiO2 samples are prepared by the modified sol-gel process. The phase formation is confirmed by XRD spectrum. Phase transformation is delayed in V-Nd co-doped TiO2 (TVN) samples compared to pure TiO2. The particle size is comparatively small in TVN samples at both the temperature 450 °C and 900 °C. Hence the effect of Nd doping is dominated over V doping in both phase transformation and grain growth process of TiO2.

Introduction: In Bangladesh among inherited genetic diseases, thalassaemias and haemoglobinopathies are common and cause significant morbidity and mortality and impose a heavy financial burden on our society. Through premarital testing it is possible to reduce the number of children affected with genetic or other blood transmitted diseases. Aim: This review aims to motivate the general populations and reanimate the interest of stakeholders involved in the management of inherited genetic disorders and put forward the recommendations and proposal for implementing premarital screening programmes in Bangladesh. Materials & Methods: Relevant literatures were retrieved from different journals and web pages to highlight the definition, advantages and importance of premarital screening, types of investigation in the screening programmes and system of implementing this programme. Discussion: Review of different literature indicates that premarital screening programme is a complex social, religious and moral issue generating legal concerns regarding the infringement of fundamental liberty, the right to marry and the implications of involuntary withdrawal of blood. In regions where inherited genetic disorders are high, knowledge and outcome of the diseases and uptake of voluntary counseling is low. This is probably because these disorders are greater in developing and under developed countries where literacy and level of understanding are low. Culture and individual attitudes also have a role in the success of testing. 103 JAFMC Bangladesh. Vol 10, No 1 (June) 2014 In Asia, voluntary premarital screening programmes began for inherited and sexually transmitted diseases in countries like China, Taiwan, Malaysia, India, Indonesia, Maldives, Singapore and Thailand but no data is available regarding premarital screening programmes in Pakistan, Nepal, Sri Lanka, Bhutan and Bangladesh. Conclusion: Paucity of resources and trained health professionals in the area of medical genetics are major impediments in implementing premarital screening programmes in Bangladesh. Besides, religious beliefs, cultural norms, social customs as well as illiteracy may be the other barriers in performing the premarital screening programmes in Bangladesh. But it is high time to undertake motivational programmes and pilot projects to implement the premarital screening programmes in order to reduce the inherited genetic disorders, especially thalassaemias and haemoglobinopathies. DOI: http://dx.doi.org/10.3329/jafmc.v10i1.22934 Journal of Armed Forces Medical College Bangladesh Vol.10(1) 2014

Introduction: Karyotyping is the process of pairing and ordering all the chromosomes of an organism, thus providing a genome-wide snapshot of an individual’s chromosome. G-banded karyograms are routinely used to diagnose a wide range of chromosomal abnormalities in individuals. Although the resolution of chromosomal changes detectable by G-banded karyotyping is typically a few megabases, this can be sufficient to diagnose certain categories of abnormalities. Objectives: The primary aim of this study was to investigate the different types of chromosomal aberrations and their relative frequencies in a group of referred patients with suspected genetic disorders. Methods: This observational study was carried out at Armed Forces Institute of Pathology (AFIP) for a period of two years from January 2011 to December 2012. A total of 131 patients were included in this study. These patients were referred to AFIP from different Combined Military Hospitals (CMH) of Bangladesh Army and also from civil medical installations. All the patients were subjected to full genetic study; complete genetic examination and pedigree construction was done to exclude nonchromosomal causes of anomaly. Detailed history and physical findings were also noted in a prescribed format. The study included peripheral lymphocyte culture by a standard method using the G–banding technique. 32 JAFMC Bangladesh. Vol 9, No 2 (December) 2013 Results: Out of 131 patients, 54 (42.2%) were male and 77 (57.8%) were female with male to female ratio 0.7:1. The age limit of the patient ranges from 04 days to 70 years. Most of the patients (32.1%) were in the age group of 0–10 years followed by 21–30 year age group (30.5%). Consanguineous marriage was found in 15 (11.5%) cases in which 3 (2.3%) cases had chromosomal aberrations. Recurrent abortion was the main clinical indication (18.3%) followed by infertility (15.3%). Chromosomal aberrations were detected in 26 patients (19.8%); of these, 20 (15.2%) involved autosomes, while only 6 (4.6%) involved gonosomes. Trisomy 21 was detected in 12 (9.1%) patients and Philadelphia chromosome was found in 8 (6.1%) patients. Turner syndrome was detected in 5 (3.8%) patients and Klinefelter syndrome was found in 1 (0.8%) patient. Conclusion: The precise delineation of different types of chromosomal aberrations is only possible using clinical examination and advanced cytogenetic tools by experienced cytogeneticists. DOI: http://dx.doi.org/10.3329/jafmc.v9i2.21823 Journal of Armed Forces Medical College Bangladesh Vol.9(2) 2013

A new salicylaldehyde-based ‘ONS’ tridentate salicylaldehyde-N(4)-diethylthiosemicarbazone (H2SANEt2) has been synthesized and characterized by elemental analyses, mass, IR, and 1H NMR spectral parameters. The coordination mode of the synthesized ligand is reported by solid state isolation and physico-chemical identification of Ni(II) and Cu(II) complexes, [Ni(SANEt2)]2 (1) and [Cu(SANEt2)]2 (2). Both complexes are neutral and oxygen-bridged dinuclear species. The ligand is bideprotonated ‘ONS’ tridentate in both complexes. IR spectral data indicate that coordination of each metal of the two complexes occurs through phenolic oxygen, azomethine nitrogen, and thiolato sulfur. X-ray crystallographic data of 1 and 2 (both monoclinic, P21/c) show a MONSO (where M=Ni and Cu) square-planar coordination around each metal. Magnetic studies of 2 show that the two Cu(II) centers are strongly antiferromagnetically coupled via the bridging phenoxo O. All the synthesized compounds were tested for their in vitro antimicrobial activities against pathogenic bacteria. The inhibition power of the complexes was greater than the parent ligand.

A new pyrazole based ‘NNS’ tridentate ligand, 5-methylpyrazole-3yl-N-(2′-methylthiophenyl)methyleneimine (MPzOATA), has been synthesized and characterized by elemental analyses, mass, IR and NMR spectroscopy. The versatile coordination mode of the ligand has been established with the synthesis of two metal–organic complexes with different metal ions, Co(III) (complex I) and Cu(II) (complex II). These metal–organic complexes have been characterized by single crystal X-ray structure analyses, along with several spectral techniques. Structural analyses of both the monomeric complexes reveal that complex I crystallized in the monoclinic C2/c space group, while complex II crystallized in the orthorhombic Pbca (#61) space group. In complex I, the Co(III) centre shows a six coordinate octahedral geometry, while in complex II, the Cu(II) centre shows a five coordinate square pyramidal geometry. The reported ligand and the metal ion complexes have been screened for their in vitro antimicrobial activity against some pathogenic bacteria.

Sol-gel prepared homogeneous Ba1 − xPbxTiO3 ceramics reveal elongation along the c-axis and contraction along the a-axis, thereby increasing the tetragonality (c/a ratio) with Pb doping. Raman spectral shape changes with composition and hardening and softening of vibrational modes are discussed and correlated to the structure and oxygen content. A new differential mode (in BaTiO3) predicted theoretically between two A1 Raman modes is experimentally detected at ∼71 cm−1. Tetragonal to cubic phase transition temperature (Tc) increases linearly with an increase in Pb content. Hence, appropriate Pb addition enhances Tc and thereby retains ferroelectricity until it reaches a higher temperature in the ceramics. Ferroelectricity in the solid solution was confirmed to enhance with an increase in Pb content from field-dependent polarization measurements. With Pb content, more than 50%, ferroelectric properties of the ceramics degrade and the materials become lossy due to the presence of O-defects originating from Pb-loss. This work provides an insight into how two well-known ferroelectric properties can be mixed to enhance its properties.

We report the case of a 60-year-old woman with Cushing disease. Magnetic resonance imaging (MRI) revealed a large sellar and suprasellar mass involving the right cavernous sinus, consistent with pituitary macroadenoma. It was resected by transsphenoidal surgery. Light microscopy revealed two separate pituitary adenomas with different histologic and immunohistochemical features. One was amphophilic and strongly Periodic Acid-Schiff (PAS) positive, the other chromophobic and PAS negative. The former tumor was immunopositive for adrenocorticotropic hormone (ACTH); approximately 30% tumor cells were immunopositive for MGMT (O6-Methylguanine-DNA Methyl-Transferase). The second tumor was a PAS negative, luteinizing hormone (LH) and alpha subunit immunopositive gonadotroph adenoma. In this tumor, about 90% of the cells were immunopositive for MGMT. The Ki-67 nuclear indices of the two tumors were 6% and 2%. Our case represents a rare combination of two morphologically different pituitary adenomas, one producing ACTH and the other LH and alpha subunit. The two tumors differed not only in Ki-67 labeling indices but in MGMT immunoexpression as well.

A systematic study on the effect of gallium (Ga) doping (0 ≤ x ≤ 0.10) on the structural phase transition and grain growth of TiO2 is reported here. X-ray diffraction spectroscopy and Raman spectroscopy confirm that Ga doping inhibits the phase transition. Activation energy increases from 125 kJ/mol (x = 0.00) to 300 kJ/mol (x = 0.10) upon Ga incorporation. X-ray photoelectron spectroscopy shows the presence of Ti3+/Ga3+ interstitials, substitution (Ti4+ by Ga3+), and oxygen vacancies in the samples. At lower doping (x ≤ 0.05), interstitials play a more significant role over substitution and oxygen vacancies, thereby resulting in a considerable lattice expansion. At higher doping (x ≥ 0.05), the effect of interstitials is compensated by both the effect of substitution and oxygen vacancies, thereby resulting in relatively lesser lattice expansion. Inhibition of the phase transition is the result of this lattice expansion. The crystallite size (anatase) and particle size (rutile) both are reduced due to Ga incorporation. It also modifies optical properties of pure TiO2 by increasing the bandgap (from 3.06 to 3.09 eV) and decreasing the Urbach energy (from 58.59 to 47.25 meV). This happens due to regularization of the lattice by the combined effect of substitution/interstitials and oxygen vacancies.

Rosai-Dorfman disease is a rare, histiocytic proliferative disorder of unknown etiology commonly affecting lymph nodes. Extranodal lesions with or without nodal involvement also occur. We report the case of a 63 year-old woman with disseminated Rosai-Dorfman disease involving the neurohypophysis and associated with adenohypophysial PRL cell hyperplasia.

The purpose of this study is to find out the prevalence of seropositivity and risk factors associated with hepatitis B virus infection. A total of 2,737 readymade garment workers were initially screened after getting departmental as well as the individuals consent and simultaneously a questionnaire was filled up by the field research assistants to assess the risk factors. Initially 59 cases were found positive for hepatitis B virus surface antigen (HBsAg) by immunochromato-graphic test. Enzyme linked immunosorbant technique was then applied to the screened positive HBsAg individuals and four cases turned out as negative and therefore a total of 55 HBsAg positive cases were detected in this factory. Statistically significant risk factors associated with HBsAg positivity were jaundice, history of previous surgery and accident, needle stick injuries and unsafe injections. This study concludes that the seropositivity found garment workers is similar to the general population of Bangladesh.