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Introduction: Newly synthesized Janus-structured Fe 3 O 4 -TiO 2 nanoparticles (NPs) appear to be a promising candidate for the diagnosis and therapy of cancer. Although the toxicity of individual Fe 3 O 4 or TiO 2 NPs has been studied extensively, the toxicity of Janus Fe 3 O 4 -TiO 2 NPs is not clear., Methods: In this study, the biosafety of both Janus Fe 3 O 4 -TiO 2 NPs (20-25 nm) and the maternal material TiO 2 NPs (7-10 nm) were evaluated in Sprague Dawley rats after one intravenous injection into the tail vein. Healthy rats were randomly divided into one control group and six experimental groups. Thirty days after treatment, rats were killed, then blood and tissue samples were collected for hematological, biochemical, element-content, histopathological, and Western blot analysis., Results: The results show that only a slight Ti element accumulation in the heart, spleen, and liver could be found in the Janus Fe 3 O 4 -TiO 2 NP groups ( P >0.05 compared with control). However, significant Ti element accumulation in the spleen, lungs, and liver was found in the TiO 2 NP-treated rats. Both Fe 3 O 4 -TiO 2 NPs and TiO 2 NPs could induce certain histopathological abnormalities. Western blot analysis showed that both NPs could induce certain apoptotic or inflammatory-related molecular protein upregulation in rat livers. A certain degree of alterations in liver function and electrolyte and lipid parameters was also observed in rats treated with both materials. However, compared to Janus structure Fe 3 O 4 -TiO 2 NP-treated groups, TiO 2 NPs at 30 mg/kg showed more severe adverse effects., Conclusion: Our results showed that under a low dose (5 mg/kg), both NP types had no significant toxicity in rats. Janus NPs certainly seem less toxic than TiO 2 NPs in rats at 30 mg/kg. To ensure safe use of these newly developed Janus NPs in cancer diagnosis and therapy, further animal studies are needed to evaluate long-term bioeffects., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Magnetic nanoparticles (NPs) have attracted great attention owing to their applications in the biomedical field. In the present work, maghemite (γFe 2 O 3 ) NPs of 6.5 nm were prepared using a sonochemical method and used to prepare magnetic beads through silanization with 3-aminopropyltrimethoxysilane (APTS). Subsequently, amino groups in the resulting APTS-γFe 2 O 3 beads were converted to carboxylic acid (CARB-γFe 2 O 3 ) through the succinic anhydride reaction, as confirmed by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and dynamic light scattering (DLS) measurements. The size of these beads was measured as 12 nm and their hydrodynamic diameter as 490 nm, using TEM analysis and DLS, respectively. The CARB-γFe 2 O 3 beads were further functionalized by immobilizing rabbit antibodies on their surfaces; the immobilization was confirmed by flow cytometry and ionic strength. The samples were further characterized by Mössbauer spectroscopy and DC magnetization measurements. Studies on magnetic relaxivities showed that magnetic beads present great potential for application in MR imaging.

This study was aimed to investigate the stability of chromosomes during meiosis in autopolyploid and allopolyploid maize, as well as to determine an association of chromosomes between maize (Zea mays ssp. mays Linnaeus, 1753) and Z. perennis (Hitchcock, 1922) Reeves & Mangelsdor, 1942, by producing a series of autopolyploid and allopolyploid maize hybrids. The intra-genomic and inter-genomic meiotic pairings in these polyploids were quantified and compared using dual-color genomic in-situ hybridization. The results demonstrated higher level of chromosome stability in allopolyploid maize during meiosis as compared to autopolyploid maize. In addition, the meiotic behavior of Z. perennis was relatively more stable as compared to the allopolyploid maize. Moreover, ten chromosomes of "A" subgenome in maize were homologous to twenty chromosomes of Z. perennis genome with a higher pairing frequency and little evolutionary differentiation. At the same time, little evolutionary differentiation has been shown by chromosomes of "A" subgenome in maize, while chromosomes of "B" subgenome, had a lower pairing frequency and higher evolutionary differentiation. Furthermore, 5I M + 5II PP + 5III MPP and 5II MM + 5II PP + 5IV MMPP were observed in allotriploids and allotetraploids respectively, whereas homoeologous chromosomes were found between the "A" and "B" genome of maize and Z. perennis .

Photothermal therapy (PTT) has emerged as one of the promising cancer therapy approaches. However, nanoparticles (NPs) which are used for PTT might be biopersistent and potentially toxic. The current research explores the promising use of Fe 3 O 4 nanoflowers as nontoxic, efficient photothermal, and strong T 2 type magnetic resonance imaging (MRI) contrast agents for imaging-guided photothermal cancer therapy. In this study, a facile solvothermal method is used to fabricate PEG-coated Fe 3 O 4 nanoflowers with controllable dimensions. Their successful fabrication, the effect of the reaction parameters, and their magnetic properties are investigated in depth. The therapeutic performance of the Fe 3 O 4 nanoflowers (Fe-NFs) is evaluated and compared with commercially available black TiO 2 nanoparticles (b-TiO 2 ) under an 808 nm laser. The photothermal therapy efficiency of the Fe-NFs is observed to be better than that of the reported Fe 3 O 4 nanoparticles. In vitro and in vivo investigation demonstrates that the therapeutic performance of the Fe-NFs is comparable to that of b-TiO 2 . Moreover, the Fe-NFs show excellent magnetic properties and magnetic resonance imaging capability to monitor therapeutic performance.

We report the development of effective drug loaded nanocarriers to combat multidrug resistant infection especially in case of osteomyelitis. The hollow mesoporous hydroxyapatite nanoparticles (hmHANPs) and solid/non-hollow hydroxyapatite nanoparticles (sHANPs) were synthesized by core-shell and co-precipitation techniques respectively. High encapsulation of the drug (ciprofloxacin) was observed in hmHANPs as compared to sHANPs, which may be due to the hollow porous structure of hmHANPs. These nanoparticles were characterized by scanning electron microscope (FESEM), N 2 adsorption/desorption, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Thermogravimetric analysis (TGA). Approximately 80% of the encapsulated drug was released at pH 4.5 within 5 days in case of hmHANPs while at pH 7.4, a sustained drug release profile was obtained and only 48.73% of the drug was released after 9 days. The results of kinetic drug release revealed that drug loaded hmHANPs showed fickian diffusion and anomalous drug diffusion mechanism at pH 4.5 and 7.4 respectively. Owing to their porous structure and high drug loading capacity, hmHANPs showed enhanced antibacterial activity against Staphylococcus aureus and Escherichia coli (drug resistant strains of osteomyelitis) in comparison to that with sHANPs. In addition, hmHANPs showed a pH sensitive drug release profile, high surface area (105.33 m 2 /g) with increased pore volume (0.533 cm 3 /g) and superior antimicrobial activity against osteomyelitis as compared to sHANPs., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We report a novel strategy for the fabrication of lecithin-coated gold nanoflowers (GNFs) via single-step design for CT imaging application. Field-emission electron microscope confirmed flowers like morphology of the as-synthesized nanostructures. Furthermore, these show absorption peak in near-infrared (NIR) region at λ max 690 nm Different concentrations of GNFs are tested as a contrast agent in CT scans at tube voltage 135 kV and tube current 350 mA. These results are compared with same amount of iodine at same CT scan parameters. The results of in vitro CT scan study show that GNFs have good contrast enhancement properties, whereas in vivo study of rabbits CT scan shows that GNFs enhance the CT image clearly at 135 kV as compared to that of iodine. Cytotoxicity was studied and blood profile show minor increase of white blood cells and haemoglobin, whereas decrease of red blood cells and platelets.

Recently, advanced designs and materials emerge to study biologically inspired neuromorphic circuit, such as oxide semiconductor devices. The existence of mobile ions in the oxide semiconductors could be somewhat regarded to be similar with the case of the ions movements among the neurons and synapses in the brain. Most of the previous studies focus on the spike time, pulse number and material species: however, a quantitative modeling is still needed to study the voltage dependence of the relaxation process of synaptic devices. Here, the gate pulse stimulated currents of oxide semiconductor devices have been employed to mimic and investigate artificial synapses functions. The modeling for relaxation process of important synaptic behaviors, excitatory post-synaptic current (EPSC), has been updated as a stretched-exponential function with voltage factors in a more quantitative way. This quantitative modeling investigation of representative synaptic transmission bias impacts would help to better simulate, realize and thus control neuromorphic computing.

Developing thiosulfate (S 2 O 3 2- ) sensors with silver nanoparticles (AgNPs) for analysis of aqueous solutions with the interference of other anions remains challenging. In this study, we propose a new strategy for excellent selective colorimetric detection of S 2 O 3 2- . The nonmorphological transition of AgNPs leading to a color change from yellow to brown is verified by UV-vis, TEM, DLS, SEM, and XPS analyses. The sensor exhibits high sensitivity with detection limits of 1.0 μM by naked-eye determination and 0.2 μM by UV-vis spectroscopy analysis. The linear relationship (R 2 = 0.998) between the (A 0 - A)/A 0 values and S 2 O 3 2- concentrations from 0.2 μM to 2.0 μM indicates that the fabricated AgNPs-based colorimetric sensor can be employed for quantitative assay of S 2 O 3 2- . Colorimetric responses are also monitored using the built-in camera of a smartphone. The sensor shows a linear response to S 2 O 3 2- in 0-20.0 μM solutions under the optimized conditions and is thus more suitable for rapid on-site tests than other detection methods. A smartphone application (app) is downloaded under Android or IOS platforms to measure the RGB (red, green, blue) values of the colorimetric sensor after exposure to the analyte. Following data processing, the RGB values are converted into concentration values by using preloaded calibration curves. Confirmatory analysis indicates that the proposed S 2 O 3 2- colorimetric sensor exhibits feasibility and sensitivity for S 2 O 3 2- detection in real environmental samples.

TiO 2 nanomaterials have been widely used for anticancer drug carriers and UV/980 nm NIR triggered cancer synergistic platforms. However, traditional pure TiO 2 nanocarriers encounter some serious drawbacks, such as low drug loading ability, limited tissue penetration of UV light, and heating effect of 980 nm NIR on normal tissue, which obstruct their further application in cancer treatment. To overcome those challenges, novel mesoporous silica (mSiO 2 ) coated black TiO 2 core-shell nanocomposites are designed and constructed as doxorubicin carriers for 808 nm NIR triggered thermal imaging guided photothermal therapy combined chemotherapy of breast cancer. Properties of the nanocomposites such as micro-morphology, size, drug loading ability and release, targeting performance, and therapy efficiency in vitro and in vivo were evaluated. The results indicated the core-shell nanocomposites with dramatically increased loading ability were pH-responsive/NIR-accelerated doxorubicin release nanocarriers and showed synergistic breast cancer treatment in vitro and in vivo. This study verifies that the newly prepared mSiO 2 coated black TiO 2 core-shell nanocarriers can overcome the limitations of traditional TiO 2 nanocarriers and thus improve and broaden usage of TiO 2 nanoparticles in nanomedicine.

Background: Ultrasound-guided transversus abdominis plane (TAP) block is done as a part of multimodal analgesia for pain relief after abdominal surgeries. This prospective randomized, double-blind, placebo-controlled trial was conducted to evaluate the postoperative analgesic efficacy of bilateral TAP block in patients undergoing midline colorectal surgeries using ropivacaine., Materials and Methods: Eighty patients scheduled for elective colorectal surgeries involving midline abdominal wall incision under general anesthesia were enrolled in this prospective randomized controlled trial. Group A received TAP block with 20 ml of 0.2% ropivacaine on either side of the abdominal wall, and Group B received 20 ml of normal saline. The time to request for rescue analgesia, total analgesic consumption in 24 h, and satisfaction with the anesthetic technique were assessed., Results: The mean visual analog scale scores at rest and on coughing were higher in control group ( P > 0.05). Time (min) to request for the first rescue analgesia was prolonged in study group compared to control group ( P < 0.001). The total tramadol consumption in 24 h postoperatively was significantly high in control group ( P < 0.001). Nausea/vomiting was more common in control group ( P > 0.05). The level of satisfaction concerning postoperative pain control/anesthetic technique was higher in study group ( P < 0.001)., Conclusion: TAP block produces effective and prolonged postoperative analgesia in patients undergoing midline colorectal surgery. It is a technically simple block to perform with a high margin of safety. It produces a considerable reduction in mean intravenous postoperative tramadol requirements, reduction in postoperative pain scores, and increased time to first request for further analgesia, both at rest and on movement., Competing Interests: There are no conflicts of interest.

Objective: To assess the 10-year risk of coronary artery disease (CAD) in subjects with impaired glucose tolerance (IGT) using Framingham risk score., Methods: Data for this study was collected from Diabetes Prevention and Awareness Program. Primary prevention team visited different primary health care centers, factories, service organizations and offices within Karachi, Pakistan. IGT was diagnosed according to World Health Organization criteria after taking informed consent. Information regarding social-demography, dietary habits and physical activities were obtained by a designed questionnaire on one-to-one based interview. Framingham risk score (FRS) was used to assess risk of developing CAD., Results: A total of 315 subjects with IGT were recruited for the study. Mean age of subjects was 44.1 ± 9.8 years and mean BMI was 27.3 ± 5.0 kg/m 2 . Overall, 31.4% of the participants were at risk of having CAD. Males were 6.4 times and hypertensive subjects were 2.44 times more likely to have CAD in next 10 years., Conclusion: According to the findings of the study, male and hypertensive IGT subjects were more likely to develop CAD in next 10 years. Community based awareness programs are needed to educate people regarding healthy lifestyle in order to reduce the risk of IGT and CAD., Competing Interests: Declaration of interests: The authors have no conflict of interests to declare.

We report a simple and mass-scalable approach for thin MoS2 films via RF sputtering combined with the post-deposition annealing process. We have prepared as-sputtered film using a MoS2 target in the sputtering system. The as-sputtered film was subjected to post-deposition annealing to improve crystalline quality at 700 °C in a sulfur and argon environment. The analysis confirmed the growth of continuous bilayer to few-layer MoS2 film. The mobility value of ~29 cm(2)/Vs and current on/off ratio on the order of ~10(4) were obtained for bilayer MoS2. The mobility increased up to ~173-181 cm(2)/Vs, respectively, for few-layer MoS2. The mobility of our bilayer MoS2 FETs is larger than any previously reported values of single to bilayer MoS2 grown on SiO2/Si substrate with a SiO2 gate oxide. Moreover, our few-layer MoS2 FETs exhibited the highest mobility value ever reported for any MoS2 FETs with a SiO2 gate oxide. It is presumed that the high mobility behavior of our film could be attributed to low charged impurities of our film and dielectric screening effect by an interfacial MoOxSiy layer. The combined preparation route of RF sputtering and post-deposition annealing process opens up the novel possibility of mass and batch production of MoS2 film.

The honeycomb lattice structure of graphene gives rise to its exceptional electronic properties of linear dispersion relation and its chiral nature of charge carriers. The exceptional electronic properties of graphene stem from linear dispersion relation and chiral nature of charge carries, originating from its honeycomb lattice structure. Here, we address the quantum Hall effect in artificially stacked graphene bilayers and single layer graphene grown by chemical vapor deposition. The quantum Hall plateaus started to appear more than 3 T and became clearer at higher magnetic fields up to 9 T. Shubnikov-de Hass oscillations were manifestly observed in graphene bilayers texture. These unusual plateaus may have been due to the layers interaction in artificially stacked graphene bilayers. Our study initiates the understanding of interactions between artificially stacked graphene layers.

The two-dimensional (2D) layered electronic materials of transition metal dichalcogenides (TMDCs) have been recently proposed as an emerging canddiate for spintronic applications. Here, we report the exfoliated single layer WS2-intelayer based spin valve effect in NiFe/WS2/Co junction from room temperature to 4.2 K. The ratio of relative magnetoresistance in spin valve effect increases from 0.18% at room temperature to 0.47% at 4.2 K. We observed that the junction resistance decreases monotonically as temperature is lowered. These results revealed that semiconducting WS2 thin film works as a metallic conducting interlayer between NiFe and Co electrodes.

A series of composite materials of general molecular formula (1 - x) Na2SO4 - (x) LDT was prepared by solid state reaction method. The phase structure and functionalization of these materials were defined by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) respectively. Differential thermal analysis (DTA) revealed that the hump of phase transition at 250 °C has decreased while its thermal stability was enhanced. Scanning electron microscopy signifies the presence of improved rigid surfaces and interphases that are accountable for the high ionic conduction due to dispersion of LDT particles in the composite systems. Arrhenius plots of the conductance show the maximum conductivity, σ = 4.56 × 10(-4) S cm(-1) at 500 °C for the x = 0.4 composition with the lowest activation energy 0.34 eV in the temperature range of 573-773 K. The value of dielectric constant was decreased with increasing frequency and follows the usual trend.

Pure zinc oxide (ZnO) and Sn-doped ZnO hexagonal sheets were synthesized by template free hydrothermal growth mechanism with controlled morphology by using zinc acetate dihydrate (Zn(CH₃COO)₂· 2H₂O), tin chloride pentahydrate (SnCl₄ · 5H₂O), Polyvinylpyrrolidone (PVP) and H₂O as precursors. The structural, physical, chemical, and magnetic characteristics were investigated by X-ray diffraction, field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy and alternating gradient magnetometer (AGM), respectively. The average crystalline size of hexagonal phase of ZnO sheets was calculated to be about 34 nm from XRD patterns. Energy dispersive spectroscopy provided the compositional analysis of pure and Sn-doped ZnO. Room temperature ferromagnetism (RTFM) was observed by AGM for pure and Sn-doped ZnO hexagonal plates. RTFM increases monotonically for Sn doping and reaches maximum saturation magnetization 0.045 emu/g for 3% Sn-doped ZnO.

Cotton has unique history of domestication, diversification, and utilization. Globally it is an important cash crop that provides raw material for textile industry. The story of cotton started from human civilization and the climax arrived with the efforts of developing transgenic cotton for various traits. Though conventional breeding brought steady improvement in developing resistance against biotic stresses but recent success story of gene transferfrom Bacillus thuringiensis into cotton showed game changing effects on cotton cultivation. Amongst various families of insecticidal proteins Bt Cry-toxins received more attention because of specificity against receptors on the cell membranes of insect midgut epithelial cells. Rapid Bt cotton adoption by farmers due to its economic and environmental benefits has changed the landscape of cotton cultivation in many countries. But the variable expression of Bt transgene in the newly developed Bt cotton genotypes in tropical environment is questionable. Variability of toxin level in different plant parts at various life stage of plant is an outcome of genotypic interaction with environmental factors. Temporal gene expression of Cry1Ac is also blamed for the epigenetic background in which transgene has been inserted. The presence of genotypes with sub-lethal level of Bt toxin might create resistance in Lepidopteron insects, limiting the use of Bt cotton in future, with the opportunityfor other resistance development strategies to get more attention like gene stacking. Until the farmers get access to more recent technology, best option is to delay the development of resistance by applying Insect Resistance Management (IRM) strategies.

The tuning of charge carrier density of graphene is an essential factor to achieve the integration of high-efficiency electronic and optoelectronic devices. We demonstrate the reversible doping in graphene using deep ultraviolet (UV) irradiation and treatment with O2 and N2 gases. The Dirac point shift towards a positive gate voltage of chemical vapor deposition grown graphene field-effect transistors confirms the p-type doping, which is observed under UV irradiation and treatment with O2 gas, while it restores its pristine state after treatment with N2 gas under UV irradiation. The emergence of an additional peak in the X-ray photoelectron spectra during UV irradiation and treatment with O2 gas represents the oxidation of graphene, and the elimination of this peak during UV irradiation and treatment with N2 gas reveals the restoration of graphene in its pristine state. The shift in the G and 2D bands in Raman spectra towards higher and then lower wavenumber also suggests p-type doping and then reversible doping in graphene. The controlled doping and its reversibility in large area grown graphene offer a new vision for electronic applications.

Magnetic resonance imaging (MRI), a sophisticated promising three-dimensional tomographic noninvasive diagnostic technique, has an intrinsic advantage in safety compared with radiotracer and optical imaging modalities; however, MRI contrast agents are less sensitive than complexes used in other imaging techniques. Usually the clinically used Gd-based complexes MRI-T 1 contrast agents are toxic; therefore, the demand for nontoxic novel T 1 -weighted MRI candidates with ultrasensitive imaging and advanced functionality is very high. In this research, silica-coated ultra-small monodispersed super-paramagnetic iron oxide nanoparticles were synthesized via a thermal decomposition method, which demonstrated themselves as a high performance T 1 -weighted MRI contrast agent for heart, liver, kidney and bladder based on in vivo imaging analyses. Transmission electron microscopy (TEM) results illustrated that the diameter of the SPIONPs was in the range of 4 nm and the average size of Fe 3 O 4 @SiO 2 was about 30-40 nm. X-ray diffraction (XRD) and Raman spectroscopy analyses revealed the phase purity of the prepared SPIONPs. These magnetite nanoparticles exhibited a weak magnetic moment at room temperature because of the spin-canting effect, which promoted a high positive signal enhancement ability. MTT assays and histological analysis demonstrated good biocompatibility of the SPIONPs in vitro and in vivo. In addition, the silica-coated ultra-small (4 nm sized) magnetite nanoparticles exhibited a good r 1 relaxivity of 1.2 mM -1 s -1 and a low r 2 /r 1 ratio of 6.5 mM -1 s -1 . In vivo T 1 -weighted MR imaging of heart, liver, kidney and bladder in mice after intravenous injection of nanoparticles further verified the high sensitivity and biocompatibility of the as-synthesized magnetite nanoparticles. These results reveal silica-coated SPIONPs as a promising candidate for a T 1 contrast agent with extraordinary capability to enhance MR images.

An emerging electronic material as one of transition metal dichalcogenides (TMDCs), tungsten disulfide (WS2) can be exfoliated as an atomically thin layer and can compensate for the drawback of graphene originating from a gapless band structure. A direct bandgap, which is obtainable in single-layer WS2, is an attractive characteristic for developing optoelectronic devices, as well as field-effect transistors. However, its relatively low mobility and electrical characteristics susceptible to environments remain obstacles for the use of device materials. Here, we demonstrate remarkable improvement in the electrical characteristics of single-layer WS2 field-effect transistor (SL-WS2 FET) using chemical vapor deposition (CVD)-grown hexagonal BN (h-BN). SL-WS2 FET sandwiched between CVD-grown h-BN films shows unprecedented high mobility of 214 cm(2)/Vs at room temperature. The mobility of a SL-WS2 FET has been found to be 486 cm(2)/Vs at 5 K. The ON/OFF ratio of output current is ~10(7) at room temperature. Apart from an ideal substrate for WS2 FET, CVD-grown h-BN film also provides a protection layer against unwanted influence by gas environments. The h-BN/SL-WS2/h-BN sandwich structure offers a way to develop high-quality durable single-layer TMDCs electronic devices.

SnO2 solid microspheres and multilayered nanocrystalline SnO2 hollow microspheres (MHS-SnO2) have been successfully synthesized in the solvothermal environment by using different solvents. The morphology, structure and composition of the as-prepared products are characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) with selected area electron diffraction (SAED) and X-ray diffraction (XRD). The growth mechanism of SnO2 solid microspheres and MHS-SnO2 are proposed and attributed to the viscosity of solvent. The studies on hydrogen absorption characteristics of SnO2 solid structure and MHS-SnO2 show an absorption capability of 0.50 wt.% and 0.92 wt.%, respectively.

Improvement of the electrical and photoelectric characteristics is essential to achieve an advanced performance of field-effect transistors and optoelectronic devices. Here we have developed a doping technique to drastically improve electrical and photoelectric characteristics of single-layered, bi-layered and multi-layered WS2 field-effect transistors (FET). After illuminating with deep ultraviolet (DUV) light in a nitrogen environment, WS2 FET shows an enhanced charge carrier density, mobility and photocurrent response. The threshold voltage of WS2 FET shifted toward the negative gate voltage, and the positions of E and A1g peaks in Raman spectra shifted toward lower wavenumbers, indicating the n-type doping effect of the WS2 FET. The doping effect is reversible. The pristine characteristics of WS2 FET can be restored by DUV light illumination in an oxygen environment. The DUV-driven doping technique in a gas environment provides a very stable, effective, easily applicable way to enhance the performance of WS2 FET.

Molybdenum disulfide (MoS2), which is one of the representative transition metal dichalcogenides, can be made as an atomically thin layer while preserving its semiconducting characteristics. We fabricated single-, bi-, and multilayer MoS2 field-effect transistor (FET) by the mechanical exfoliation method and studied the effect of deep ultraviolet (DUV) light illumination. The thickness of the MoS2 layers was determined using an optical microscope and further confirmed by Raman spectroscopy and atomic force microscopy. The MoS2 FETs with different number of layers were assessed for DUV-sensitive performances in various environments. The photocurrent response to DUV light becomes larger with increasing numbers of MoS2 layers and is significantly enhanced in N2 gas environment compared with that in atmospheric environment.

The properties of graphene are strongly affected by metal adsorbates and clusters on graphene. Here, we study the effect of a thin layer of platinum (Pt) metal on exfoliated single, bi- and trilayer graphene and on chemical vapor deposition-grown single-layer graphene by using Raman spectroscopy and transport measurements. The Raman spectra and transport measurements show that Pt affects the structure as well as the electronic properties of graphene. The shift of peak frequencies, intensities and widths of the Raman bands were analyzed after the deposition of Pt with different thicknesses (1, 3, 5 nm) on the graphene. The shifts in the G and 2D peak positions of the Raman spectra indicate the n-type doping effect by the Pt metal. The doping effect was also confirmed by gate-voltage dependent resistivity measurements. The doping effect by the Pt metal is stable under ambient conditions, and the doping intensity increases with the increasing Pt deposition without inducing a severe degradation of the charge carrier mobility.

Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO 3 ) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO 3 . The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO 3 provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.

The edge oxidation effects of chemical-vapor-deposition-grown graphene devices with nanoconstrictions of different sizes are presented. The effects of edge oxidation on the doping level of a nanoconstriction graphene device were identified by Raman spectroscopy and using the back-gate-voltage-dependent resistance. Strong p-type doping was observed as the size of nanoconstriction decreased. The Dirac point of the graphene device shifted toward positive voltage, and the positions of the G and 2D peaks in Raman spectroscopy shifted toward a higher wave number, indicating the p-type doping effect of the graphene device. p-type doping was lifted by deep-ultraviolet light illumination under a nitrogen atmosphere at room temperature. p-type doping was restored by deep-ultraviolet light illumination under an oxygen atmosphere at room temperature. Edge oxidation in the narrow structures explains the origin of the p-type doping effect widely observed in graphene nanodevices.

Joint FAO/WHO expert's consultation report defines probiotics as: Live microorganisms which when administered in adequate amounts confer a health benefit on the host. Most commonly used probiotics are Lactic acid bacteria (LAB) and bifidobacteria. There are other examples of species used as probiotics (certain yeasts and bacilli). Probiotic supplements are popular now a days. From the beginning of 2000, research on probiotics has increased remarkably. Probiotics are now day's widely studied for their beneficial effects in treatment of many prevailing diseases. Here we reviewed the beneficiary effects of probiotics in some diseases.

Narrow genetic base and complex allotetraploid genome of cotton (Gossypium hirsutum L.) is stimulating efforts to avail required polymorphism for marker based breeding. The availability of draft genome sequence of G. raimondii and G. arboreum and next generation sequencing (NGS) technologies facilitated the development of high-throughput marker technologies in cotton. The concepts of genetic diversity, QTL mapping, and marker assisted selection (MAS) are evolving into more efficient concepts of linkage disequilibrium, association mapping, and genomic selection, respectively. The objective of the current review is to analyze the pace of evolution in the molecular marker technologies in cotton during the last ten years into the following four areas: (i) comparative analysis of low- and high-throughput marker technologies available in cotton, (ii) genetic diversity in the available wild and improved gene pools of cotton, (iii) identification of the genomic regions within cotton genome underlying economic traits, and (iv) marker based selection methodologies. Moreover, the applications of marker technologies to enhance the breeding efficiency in cotton are also summarized. Aforementioned genomic technologies and the integration of several other omics resources are expected to enhance the cotton productivity and meet the global fiber quantity and quality demands.

In this article, we study the use of thermally reduced graphene (TRG) for oil spill cleanup. TRG was synthesized by thermal exfoliation of graphite oxide and characterized by X-ray diffusion, Raman spectroscopy, SEM, TEM, elemental analysis, and Brunauer-Emmett-Teller (BET) surface area measurement. Various aspects of the sorption process have been studied including the sorption capacity, the recovery of the adsorbed oil, and the recyclability of TRG. Our results shows that TRG has a higher sorption capacity than any other carbon-based sorbents, with sorption capacity as high as 131 g of oil per gram TRG. With recovery of the sorbed oil via filtration and reuse of TRG for up to six cycles, 1 g of TRG collectively removes approximately 300 g of crude oil. Moreover, the effects of TRG bulk density, pore volume, and carbon/oxygen ratio and the oil viscosity on the sorption process are also discussed.

In this work, we have reported a template-free hydrothermal approach to fabricate highly pure single phase ZnMn2O4 pen-type nano needles assembled with flower type nanostructures. The X-Ray Diffraction, Scanning Electron Microscopy, Energy Dispersive X-Ray spectroscopy, Raman Spectroscopy, Transmission Electron Microscopy, High Resolution Transmission Electron Microscopy, Selected Area Electron Diffraction and UV-visible spectroscopy techniques were used to study the structural and optical properties of Pen-type nanoneedles assembled with flower like nanostrucutres. Single crystalline hetaerolite ZnMn2O4 pen type nanoneedles of flower like nanostructures have an average diameter of 250 nm. Room temperature Raman spectroscopy reveals the four fundamental vibrational modes. Room temperature UV-vis spectrometer was used to determine the transmittance behaviour pen type nanoneedles of flower like nanostructures. Direct optical band gap of 2.19 eV was acquired by using Davis-Mott model. The UV-visible spectrum points out that the absorption is prominent in visible region and transparency is more than 80% in UV region.

Tin monoxide is a significant functional semiconductor material which employed to a wide area of applications especially optical and energy storage devices. Presently, template free hydrothermal technique has been employing to synthesize stannous oxide (SnO) clinopinacoid type controlled morphology using SnCl2 x 2H2O, NH3, and H2O as raw materials. The crystalline phase, morphology, particle size and component were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and field-emission scanning electron microscopy (FESEM). FESEM results exhibited the large scale homogeneous growth of clinopinacoid architecture with the obvious size of 5 - 7 micrometers. The XRD results showed that the average crystallite size of the tetragonal phase romarchite SnO was about 29 nm calculated from the FWHM of X-ray diffraction pattern. The dominant Raman active modes A(1g) = 205 cm(-1), B(1g) = 105-107 cm(-1) and about 6 cm(-1) redshift were observed by the Raman spectroscopy, which further confirmed the existence of the nano tetragonal phase SnO. The electrochemical performance of as-synthesized SnO clinopinacoid structure as the anode material for lithium ion batteries was investigated. It was observed that the first discharge capacity of the two samples could reach a very high value of 1502 mA h g(-1) and 1422 mA h g(-1) respectively. The effect of nitrogen concentration on morphology as well as cyclic performance of Li-Ion-batteries was also discussed.

A simple and selective RP-HPLC-UV method with SPE was developed and validated for the quantification of cefotaxime in all-in-one total parenteral nutrition (AIO-TPN) admixtures. Chromatographic separation was achieved on a 5 pm particle size C18 DB column (250 x 4.6 mm id) using the mobile phase ammonium acetate (25 mM, pH 4.0)-50% acetonitrile in methanol (80 + 20, v/v). The flow rate was 0.9 mL/min and the detection wavelength was 254 nm. The analyte was extracted from AIO-TPN admixtures by means of an SPE method. The cefotaxime calibration curve was linear over a concentration range of 100-1400 microg/mL with a correlation coefficient of > or = 0.9994. The intraday accuracy and precision for cefotaxime were < or = -3.15 and < or = 3.08%, respectively, whereas the interday accuracy and precision were < or = -2.48 and < or = 2.25%, respectively. The method was successfully applied to stability studies of cefotaxime in the presence of micronutrients together with low and high concentrations of macronutrients in AIO-TPN admixtures. Cefotaxime was degraded by 13.00 and 26.05% at room temperature (25 +/- 2 degrees C) after 72 h in low and high macronutrient concentration formulations of AIO-TPN admixtures, respectively. The values of cefotaxime degradation rates for low and high macronutrient concentration formulations of AIO-TPN admixtures were -0.164 and -0.353, respectively. These results indicated that there was a higher rate of degradation in the AIO-TPN admixture formulations containing high concentrations of macronutrients.

Objective: To develop and evaluate a risk score to predict people at high risk of developing type 2 diabetes in Pakistan., Methodology: Cross sectional data regarding primary prevention of diabetes in Pakistan. Diabetes risk score was developed by using simple parameters namely age, waist circumference, and family history of diabetes. Odds ratios of the model were used to assign a score value for each variable and the diabetes risk score was calculated as the sum of those scores., Results: We externally validated the score using two data from 1264 subjects and 856 subjects aged 25 years and above from two separate studies respectively. Validating this score using the first data from the second screening study gave an area under the receive operator characteristics curve [AROC] of 0.758. A cut point of 4 had a sensitivity of 47.0% and specificity of 88% and in the second data AROC is 0.7 with 44% sensitivity and 89% specificity., Conclusions: A simple diabetes risk score, based on a set of variables can be used for the identification of high risk individuals for early intervention to delay or prevent type 2 diabetes in Pakistani population., (Copyright © 2012 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.)

We prepare thin single-walled carbon nanotube networks on a transparent and flexible substrate with different densities, using a very simple spray method. We measure the electric impedance at different frequencies Z(f) in the frequency range of 40 Hz to 20 GHz using two different methods: a two-probe method in the range up to 110 MHz and a coaxial (Corbino) method in the range of 10 MHz to 20 GHz. We measure the optical absorption and electrical conductivity in order to optimize the conditions for obtaining optimum performance films with both high electrical conductivity and transparency. We observe a square resistance of 1 to 8.5 kΩ for samples showing 65% to 85% optical transmittance, respectively. For some applications, we need flexibility and not transparency: for this purpose, we deposit a thick film of single-walled carbon nanotubes on a flexible silicone substrate by spray method from an aqueous suspension of carbon nanotubes in a surfactant (sodium dodecyl sulphate), thereby obtaining a flexible conducting electrode showing an electrical resistance as low as 200 Ω/sq. When stretching up to 10% and 20%, the electrical resistance increases slightly, recovering the initial value for small elongations up to 10%. We analyze the stretched and unstretched samples by Raman spectroscopy and observe that the breathing mode on the Raman spectra is highly sensitive to stretching. The high-energy Raman modes do not change, which indicates that no defects are introduced when stretching. Using this method, flexible conducting films that may be transparent are obtained just by employing a very simple spray method and can be deposited on any type or shape of surface.

The aims of the present study were to characterize the relationship between plasma racemic methadone and its enantiomers' concentrations with respect to their pharmacodynamic effects and to investigate the influence of potential covariates on the pharmacodynamic parameters in patients on methadone maintenance treatment (MMT). Eighty-eight regular subjects at the Sheffield Care Trust Substance Misuse Services were studied. Samples of blood and urine were collected before the daily dose of methadone. Blood samples were taken up to 5 hours after dose. Total plasma concentrations of (RS)-methadone and total and unbound plasma concentrations of both enantiomers were measured by liquid chromatography-mass spectrometry. The Total Mood Disturbance Score (TMDS), the Objective Opioid Withdrawal Scale (OOWS), and the Subjective Opioid Withdrawal Scale (SOWS) were used as measures of mood and withdrawal. Population pharmacokinetic/pharmacodynamic analysis and subsequent multiple regression analysis were used to determine the factors influencing the pharmacodynamic effects of methadone. Significant decreases (P ≤ 0.04) were observed in the scores for the TMDS, SOWS, and OOWS for 5 hours after methadone dosage. The TMDS had returned to baseline by 10 hours after dose (P = 0.98), at which time the SOWS remained significantly below baseline (P = 0.001). Multiple regression analysis revealed that 33% of the overall variation in unbound (R)-methadone EC50 was explained by 3 variables, namely CYP3A activity (9%), age (16%), and sex (8%). Age also accounted for 8% and 9% of the variation in total (rac)- and (R)-methadone EC50. The present study has confirmed that the duration of mood change in the present study was shorter than the effect of methadone in stabilizing withdrawal symptoms. Thus, it is likely that a once-daily dose of methadone, albeit effective for preventing withdrawal, may not be sufficient to improve mood in some patients. Finally, it was established that CYP3A activity, years of dependent use, sex, and age are major determinants of methadone EC50 with respect to TMDS.

The properties of single-layer graphene are strongly affected by metal adsorbates and clusters on graphene. Here, we study the effect of a thin layer of chromium (Cr) and titanium (Ti) metals on chemical vapor deposition (CVD)-grown graphene by using Raman spectroscopy and transport measurements. The Raman spectra and transport measurements show that both Cr and Ti metals affect the structure as well as the electronic properties of the CVD-grown graphene. The shift of peak frequencies, intensities and widths of the Raman bands are analyzed after the deposition of metal films of different thickness on CVD-grown graphene. The shifts in G and 2D peak positions indicate the doping effect of graphene by Cr and Ti metals. While p-type doping was observed for Cr-coated graphene, n-type doping was observed for Ti-coated graphene. The doping effect is also confirmed by measuring the gate voltage dependent resistivity of graphene. We have also found that annealing in Ar atmosphere induces a p-type doping effect on Cr- or Ti-coated CVD-grown graphene.

Aromatic basmati rice is vulnerable to bacterial blight disease. Genes conferring resistance to bacterial blight have been identified in coarse rice; however, their incorporation into basmati varieties compromises the prized basmati aroma. We identified bacterial blight resistance genes Xa4, xa5, Xa7, and xa13 in 52 basmati landraces and five basmati cultivars using PCR markers. The Xa7 gene was found to be the most prevalent among the cultivars and landraces. The cultivars Basmati-385 and Basmati-2000 also contained the Xa4 gene; however, xa5 and xa13 were confined to landraces only. Ten landraces were found to have multiple resistance genes. Landraces Basmati-106, Basmati-189 and Basmati-208 contained Xa4 and Xa7 genes. Whereas, landraces Basmati-122, Basmati-427, Basmati-433 were observed to have xa5 and Xa7 genes. Landraces Basmati-48, Basmati-51A, Basmati-334, and Basmati-370A possessed Xa7 and xa13 genes. The use of landraces containing recessive genes xa5 and xa13 as donor parents in hybridization with cultivars Basmati-385 and Basmati-2000, which contain the genes Xa4 and Xa7, will expedite efforts to develop bacterial blight-resistant basmati rice cultivars through marker assisted selection, based on a pyramiding approach, without compromising aroma and grain quality.

The popularity of genetically modified insect resistant (Bt) cotton has promoted large scale monocultures, which is thought to worsen the problem of crop genetic homogeneity. Information on genetic diversity among Bt cotton varieties is lacking. We evaluated genetic divergence among 19 Bt cotton genotypes using simple sequence repeat (SSR) markers. Thirty-seven of 104 surveyed primers were found informative. Fifty-two primers selected on the basis of reported intra-hirsutum polymorphism in a cotton marker database showed a high degree of polymorphism, 56% compared to 13% for randomly selected primers. A total of 177 loci were amplified, with an average of 1.57 loci per primer, generating 38 markers. The amplicons ranged in size from 98 to 256 bp. The genetic similarities among the 19 genotypes ranged from 0.902 to 0.982, with an average of 0.947, revealing a lack of diversity. Similarities among genotypes from public sector organizations were higher than genotypes developed by private companies. Hybrids were found to be more distant compared to commercial cultivars and advanced breeding lines. Cluster analysis grouped the 19 Bt cotton genotypes into three major clusters and two independent entries. Cultivars IR-3701, Ali Akbar-802 and advanced breeding line VH-259 grouped in subcluster B2, with very narrow genetic distances despite dissimilar parentage. We found a very high level of similarity among Pakistani-bred Bt cotton varieties, which means that genetically diverse recurrent parents should be included to enhance genetic diversity. The intra-hirsutum polymorphic SSRs were found to be highly informative for molecular genetic diversity studies in these cotton varieties.

Background: The aim of this study was to discover the association of serum high-sensitivity C-reactive protein (hsCRP) with various risk factors for metabolic syndrome in an urban population of Karachi, Pakistan., Method: In this cross-sectional study, 337 healthy adults (108 males and 229 females, mean age 40.7 ± 14.2 years) participated. The subjects were randomly selected in Lyari Town in Karachi using a geographical imaging system (GIS). Their demographic, anthropometric [body mass index (BMI), hip and waist circumferences, waist-to-hip circumference ratio (W-HR), and biochemical (fasting blood glucose, fasting insulin, fasting lipid profile, and hsCRP)] parameters were recorded. Insulin resistance was calculated by the homeostasis model assessment (HOMA-IR). Metabolic syndrome was diagnosed according to the International Diabetes Federation (IDF) criteria. Correlation of CRP and fasting insulin levels with various parameters of metabolic syndrome were calculated using Pearson correlation., Results: Median CRP levels were found to be higher in females 0.81 (0.20-1.38) compared with males 0.77 (0.19-1.35). Metabolic syndrome was diagnosed in 108 (31.12%) subjects. No significant difference between CRP levels in the metabolic syndrome-positive and metabolic syndrome-negative groups was observed. Similarly, no correlation was observed between hsCRP and fasting insulin levels, insulin resistance, and other parameters of MS., Conclusion: There is lack of correlation between hsCRP levels and various risk factors for metabolic syndrome in our urban population. Further large-scale prospective studies are needed to confirm these findings.

Forty sugarcane genotypes (clones), including elite lines, commercial cultivars of Saccharum officinarum and S. barberi clones, were fingerprinted with 30 RAPD markers, using a PCR-based marker assay. The genetic distance for RAPD data was determined according to Nei, and relationships between accessions were graphed in a dendrogram. Genetic distance values ranging from 16.2 to 86.3% were observed among the 40 sugarcane accessions. The lowest genetic distance was found between genotypes US-406 and US-186. These two genotypes differed from each other in only 25 bands with 15 different primers. Genotypes Col-54 and CP-72-2086 were the second most similar group, with a genetic distance of 19.46%. The most dissimilar of all the accessions were CP-77-400 and US-133, with a genetic distance of 86.3%. RAPD fingerprints help sugarcane breeders clarify the genetic pedigree of commercial sugarcane varieties and can be used to evaluate the efficiency of conventional breeding methods.