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Bimetallic nanoparticles (BNPs) have drawn significant attention due to their numerous applications. They demonstrate enhanced optical, electrical, thermal, and catalytic properties due to the synergistic effects of monometals present in them. In this work, CuAg and AuAg BNPs have been synthesized using a facile and economical chemical reduction method. Optical characterization was carried out using UV–visible spectroscopy, and effect of pH on optical absorbance was studied. For CuAg and AuAg BNPs, optimum pH was observed to be at 9.4 and 6.39, respectively. Morphological investigation confirms the average diameters of CuAg and AuAg BNPs were to be 65 nm and 30 nm, respectively. Photocatalytic property illustrates the reduction of 4-nitrophenol to 4-aminophenol with a 92% conversion percentage in the presence of CuAg BNPs in 4 min, and rate constant for the reaction was measured to be 8.98 × 10–3 s−1. But for the AuAg BNPs, the conversion percentage was 97% in 8 min and rate constant was found to be 7.95 × 10–3 s−1. Thermal conductivity and viscosity measurements of the nanofluids obtained with CuAg and AuAg BNPs have ascertained them to be efficient candidates for the heat transfer and catalytic applications. Graphic abstract

Single-walled carbon nanotube (SWCNT) wrapped GeO2/ZnWO4 nanocomposite was prepared by single-step solvothermal method. In this work, GeO2/ZnWO4 nanocomposites were prepared by varying the molar percentage of GeO2 and by further adding SWCNT for the composite to boost the electrochemical performance. The prepared GeO2/ZnWO4 nanocomposites and GeO2/ZnWO4@CNT nanocomposite are used as anode material for lithium-ion battery (LIB). As expected, GeO2/ZnWO4@CNT nanocomposite exhibits higher capacities and good rate capability than the GeO2/ZnWO4 nanocomposite. The GeO2/ZnWO4@CNT nanocomposite exhibits 930 mAh g−1 discharge capacity and 533 mAh g−1 charge capacity for the initial cycle at 100 mAh g−1 in the voltage range of 0.01–3 V (vs. Li+/Li). Even at high current density of 500 mAh g−1, GeO2/ZnWO4@CNT nanocomposite shows 231 mAh g−1 and 257 mAh g−1 charge/discharge capacity which are higher than that of GeO2/ZnWO4 nanocomposite. The GeO2/ZnWO4@CNT nanocomposite delivers 75.8% capacity retention and 100% coulombic efficiency even after 400 cycles at 300 mAh g−1. These results direct that GeO2/ZnWO4@CNT nanocomposite is a good negative electrode for lithium-ion battery.

The pristine ZnWO4 and ZnWO4/r-GO nanocomposite synthesized by the facile solvothermal method were tested as anode materials for lithium-ion battery. Ex situ X-ray photoelectron spectroscopy (XPS) confirms the elemental composition of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite. The ZnWO4/r-GO nanocomposite shows mesoporous nature and exhibits 50.802 m2 g−1 BET specific surface area, which is higher than that of pristine ZnWO4. In addition, the electrochemical property of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite investigated using 2032 half-cell reveals that GO enhances the electrochemical property of the ZnWO4. The ZnWO4/r-GO nanocomposite not only exhibits higher discharge capacity of 1158 mAh g−1 at 100 mA g−1 but also shows longer and stable cycle life at 300 mA g−1 current density. The ZnWO4/r-GO nanocomposite exhibits 80.74% capacity retention even after 500 cycles. The synergetic effect of r-GO and ZnWO4 improves the capacity, columbic efficiency, and stability of the material. The results indicate that ZnWO4/r-GO nanocomposite is an interesting anode material for Li-ion battery with higher capacity complemented with stability compared to pristine ZnWO4.

A combination of Taguchi methodology and Grey Relational Analysis (GRA) inturn coupled with principal component analysis (PCA) has been proposed through this paper. This methodology is adopted in order to evaluate and estimate the effect of machining parameters over the output responses of Wire Electrical-Discharge Machining (WEDM) performed on Magnesium based metal matrix composite. In this research, an optimal combination of process parameter was expected to be finalized so as to attain a state of maximum Material Removal Rate (MRR) that too with minimal surface roughness (Ra) value. WEDM of developed composite specimens were confirmed to be of L27 orthogonal array(OA) using Taguchi’s method, based mainly on control factors namely reinforcement weight percentage (wt.%), Doping (DP %), Pulse ON time (T-ON), Pulse OFF time (T-OFF) and wire feed rate (WF). ANOVA outcome reveals that wt.% and DP% are the most influencing parameter for MRR and Ra. Multiobjective responses were normalized using GRA; further PCA was applied to evaluate the weighting values corresponding to each performance. The optimial parameter was set and the final results obtained depending on the optimal combination was found to be with a maximum MRR of 14.9 mm3/min and a minimum Ra of 2.04 μm.

In this communication, we present a systematic investigation on structural, electric, magnetic and thermoelectric power properties of REMnO3 (RE = Dy, Gd, Eu and Sm) manganites which were prepared using solid-state reaction route. The samples exhibit orthorhombic crystal structure with Pbnm space group. Rietveld analysis of x-ray diffraction (XRD) data shows that the unit cell volume increases with increase in ionic radii of the rare earth ion, $r_{\text {RE}}$ . The particle size was calculated from the scanning electron microscope (SEM) images. The estimated particle size is observed to decrease with increasing ionic radii of the rare earth ions. All samples exhibit insulating behaviour and display immeasurably high resistivity at low temperatures. Magnetization studies indicate that the samples display a transition in the low temperature region. Magnetization data also reveals that antiferromagnetic behaviour is observed for all samples. Thermoelectric power results show that large thermoelectric power is seen for these manganites. Thermoelectric power of high-temperature region was successfully analysed using small polaron hopping (SPH) model.

MicroRNAs (miRNAs) are small RNA molecules that affect cellular processes by controlling gene expression. Recent studies have shown that hypoxia downregulates Drosha and Dicer, key enzymes in miRNA biogenesis, causing a decreased pool of miRNAs in cancer and resulting in increased tumor growth and metastasis. Here we demonstrate a previously unrecognized mechanism by which hypoxia downregulates Dicer. We found that miR-630, which is upregulated under hypoxic conditions, targets and downregulates Dicer expression. In an orthotopic mouse model of ovarian cancer, delivery of miR-630 using 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanoliposomes resulted in increased tumor growth and metastasis, and decreased Dicer expression. Treatment with the combination of anti-miR-630 and anti-vascular endothelial growth factor antibody in mice resulted in rescue of Dicer expression and significantly decreased tumor growth and metastasis. These results indicate that targeting miR-630 is a promising approach to overcome Dicer deregulation in cancer. As demonstrated in the study, use of DOPC nanoliposomes for anti-miR delivery serves as a better alternative approach to cell line-based overexpression of sense or antisense miRNAs, while avoiding potential in vitro selection effects. Findings from this study provide a new understanding of miRNA biogenesis downregulation observed under hypoxia and suggest therapeutic avenues to target this dysregulation in cancer.

Thrombocytosis is present in more than 30% of patients with solid malignancies and correlates with worsened patient survival. Tumor cell interaction with various cellular components of the tumor microenvironment including platelets is crucial for tumor growth and metastasis. Although it is known that platelets can infiltrate into tumor tissue, secrete pro-angiogenic and pro-tumorigenic factors and thereby increase tumor growth, the precise molecular interactions between platelets and metastatic cancer cells are not well understood. Here we demonstrate that platelets induce resistance to anoikis in vitro and are critical for metastasis in vivo. We further show that platelets activate RhoA-MYPT1-PP1-mediated YAP1 dephosphorylation and promote its nuclear translocation which induces a pro-survival gene expression signature and inhibits apoptosis. Reduction of YAP1 in cancer cells in vivo protects against thrombocytosis-induced increase in metastasis. Collectively, our results indicate that cancer cells depend on platelets to avoid anoikis and succeed in the metastatic process., Platelets have been associated with increased tumor growth and metastasis but the mechanistic details of this interaction are still unclear. Here the authors show that platelets improve anoikis resistance of cancer cells and increase metastasis by activating Yap through a RhoA/MYPT-PP1 pathway.

In the present communication, a systematic study of electrical, structural, and thermal measurements is done for low bandwidth compounds of Dy1−xSr x MnO3. All the samples are prepared using solid-state reaction method. XRD patterns were refined using Rietveld method, and it is seen that all the compounds are single phased. It is demonstrated that the small polaron hopping (SPH) model valid for high-temperature regime, whereas in the low-temperature regime, the variable-range hopping (VRH) model is valid. Thermoelectric power measurements demonstrate that these samples show colossal values of thermoelectric power (S). We are perhaps reporting for the first time the largest value of S ever observed in any manganite.

A deeper mechanistic understanding of tumour angiogenesis regulation is needed to improve current anti-angiogenic therapies. Here we present evidence from systems-based miRNA analyses of large-scale patient data sets along with in vitro and in vivo experiments that miR-192 is a key regulator of angiogenesis. The potent anti-angiogenic effect of miR-192 stems from its ability to globally downregulate angiogenic pathways in cancer cells through regulation of EGR1 and HOXB9. Low miR-192 expression in human tumours is predictive of poor clinical outcome in several cancer types. Using 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) nanoliposomes, we show that miR-192 delivery leads to inhibition of tumour angiogenesis in multiple ovarian and renal tumour models, resulting in tumour regression and growth inhibition. This anti-angiogenic and anti-tumour effect is more robust than that observed with an anti-VEGF antibody. Collectively, these data identify miR-192 as a central node in tumour angiogenesis and support the use of miR-192 in an anti-angiogenesis therapy., The formation of blood vessels in tumours, angiogenesis, is a promising target for therapy. Here, the authors show that microRNA192 has anti-angiogenic functions and negatively regulates EGR1 and HOXB9, and that delivery of this microRNA to tumours in vivo can reduce angiogenesis and tumour growth.

The humidity sensing property of the ferrite systems Ni x Cu0.8−x Zn0.2Fe2O4 with 0.0 ≤ x ≤ 0.8 (x = 0, 0.2, 0.4, 0.6, 0.8) was studied using the standard ceramic technique. The spinel structure of the compounds was confirmed by X-ray diffraction studies, BET study and surface morphology by scanning electron microscopy. The compounds were subjected to dc electrical conductivity studies at room temperature. The resistance measurements as a function of relative humidity (RH) in the range of 5–98% were done and the humidity sensing factors (S f = R 5%/R 95%) were calculated. The composite NiCuZn-3 (x = 0.4) possessed the highest humidity sensing factor of 3051.9 ± 500, whilst CuZn–1 (x = 0) possessed the lowest humidity sensing factor of 45.3 ± 12. The other compounds possessed lower humidity sensing factors of 116.7 ± 35, 783.4 ± 160 and 416.2 ± 65 for x = 0.2, 0.6 and 0.8, respectively.

Ovarian cancer is a highly metastatic disease, but no effective strategies to target this metastatic process currently are known. Here, an integrative computational analysis of The Cancer Genome Atlas ovarian cancer dataset coupled with experimental validation identified a novel zinc finger transcription factor ZNF304 as one of the key factors for ovarian cancer metastasis. High tumoral ZNF304 expression was associated with poor overall survival in ovarian cancer patients. Through reverse phase protein array analysis, we demonstrated that ZNF304 promotes multiple proto-oncogenic pathways important for cell survival, migration, and invasion. ZNF304 transcriptionally regulates β1 integrin, which subsequently regulates Src/focal adhesion kinase and paxillin and prevents anoikis. In vivo delivery of ZNF304 siRNA by a novel dual assembly nanoparticle led to sustained gene silencing for 14 days, increased anoikis, and reduced tumor growth in orthotopic mouse models of ovarian cancer. Taken together, ZNF304 is a novel transcriptional regulator of β1 integrin, promotes cancer cell survival, and protects against anoikis in ovarian cancer.

Heterobinuclear manganese-molybdenum complex with the Schiff base prepared by the condensation of diethylenetriamine with salicylaldehyde yielded a polymeric mixed metal coordination complex with the composition of [Mn1·5MoO3L]. The infrared spectral data indicated the presence of azomethine (HC=N) and Mo=O groups.1H NMR further confirmed the coordination of azomethine nitrogen and absence of phenolic hydrogen. The EPR studies suggested the presence of Mn(II) in the complex. The solid state conductivity studies with the variation of potential and temperature indicated a specific conductivity of 1·6×10−5 ohm−1 cm−1. The activation energy was found to be 0·019 eV. Hall measurements indicate that the material isp-type which is further confirmed by iodine doping which increases the conductivity by two orders of magnitude.

Nature Communications 4: Article number: 1403 (2013); Published: 29 January 2013; Updated: 29 July 2013. The original version of this Article contained a typographical error in the spelling of the author Mian M. K. Shahzad, which was incorrectly given as Mian M. K. Shazhad. This has now been corrected in both the PDF and HTML versions of the Article.

An organised heterosupramolecular assembly is prepared by attachment of linked molecular components to previously organised condensed phase nano-components. The above approach yields an intrinsic substrate through which the resultant molecular device may be modulated. Further, the modulation state can be inferred from the bulk properties of the intrinsic substrate. Specifically, we report results for a heterosupermolecule consisting of a TiO2 nanocrystallite attached to a linked viologen-quinone unit. The associated function is photo-induced vectorial electron flow. For the corresponding organised assembly we demonstrate the following: bandgap excitation of a semiconductor nanocrystallite results in light-induced vectorial electron flow; electrochemical modulation of the bulk properties of the intrinsic nanocrystalline semiconductor substrate modulates function; and the state of the intrinsic substrate provides information about the modulation state of the constituent units of the assembly.

Thin films of clathrate material have been grown using the laser ablation technique on a variety of substrates. Films deposited on silicon substrates exhibited a significant deficiency of Ga and Ge while the stoichiometry was preserved in films deposited on quartz, sapphire, and glass substrates. Ablation characteristics of the clathrate target for laser radiation at three different wavelengths in the UV, visible and IR were studied. The UV and IR laser wavelengths produce low ablation thresholds and high growth rates. Crystalline films were obtained above a growth temperature of 400°C. Conductivity measurements on the films at low current injection (

Noninvasive ventilation (NIV) is now the accepted first-line treatment for acidotic exacerbations of chronic obstructive pulmonary disease (COPD). Many hospitals perform NIV in a ward-based unit outside the ICU. Patients are still admitted to the ICU when failure of NIV may lead to mechanical ventilation, or for bed resource reasons. The impact of the opening of a ward-based NIV unit at University Hospital Aintree in July 2004 is described.