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The elucidation of spontaneous growth of metal whiskers from metal surfaces is still ongoing, with the mainstream research conducted on Sn whiskers. This work reports on the discovery of Pb whisker growth from Bi-Mg-Pb solid pools found in common machinable aluminum alloy. The whiskers and hillocks display unique morphologies and complex growth that have not been documented beforehand. In contrast to typical understanding of whisker growth, the presented Pb whiskers show a clear nanocrystalline induced growth mechanism, which is a novel concept. Furthermore, the investigated whiskers are also found to be completely composed of nanocrystals throughout their entire length. The performed research gives new insight into nucleation and growth of metal whiskers, which raises new theoretical questions and challenges current theories of spontaneous metal whisker growth. Additionally, this work provides the first microscopic confirmation of recrystallization growth theory of whiskers that relates to oriented attachment of nanocrystals formed within an amorphous metallic matrix. The impact of mechanical stress, generated through Bi oxidation within the pools, is theoretically discussed with relation to the observed whisker and hillock growth. The newly discovered nanocrystalline growth provides a new step towards understanding spontaneous metal whisker growth and possibility of developing nanostructures for potential usage in sensing and electronics applications.

Phase-transfer catalytic epoxidation activity of nanosized {Mo72Cr30} Keplerate polyoxometalate in ethanol in the presence of hydrogen peroxide is exploited. The nanocluster acts as a homogeneous catalyst upon treatment with hydrogen peroxide, while it can be easily filtered and reused as a heterogeneous catalyst. The high catalytic activity and durability of catalyst was demonstrated.

Importance of renewable-energy resources because of scarcity, greenhouse-gas emissions, and their fundamental roles in production and sustainable development, has made governments to reduce energy consumption and improving energy efficiency. In this regard, targeting subsidies rule was running in Iran since 2010. Since energy additionaly to labor and capital is one of the important inputs in production, running this rule with increasing energy price, affects manufacturing industries due to the type of energy and industry. In this research, the impacts of price liberalization on electricity efficiency have evaluated. Partial adjustment model, generalized method of moment and energy intensity measure are applied to this purpose. Data are collected from Statistical Center of Iran during 1995-2013. The research innovations are: using a partial adjustment model in evaluating efficiency, assessment whole industrial groups, and the period of research. The results show that in 95 percent level of confidence, the Iranian manufacturing industries are significantly flexible for changing the use of electricity. But the electricity efficiency has gotten worse after running the rule. In general, apposite of expectations, targeting subsidies rule has failed to improve electricity efficiency at least in short run.

Using two entangled optical beams and post-selection, a single photon can have the same effect as eight photons in terms of the induced phase shift. This example illustrates the power of the so-called weak-value amplification.

In this work, Fe2O3 nanoparticles (NPs) were successfully synthesized by Pechini sol-gel method. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction characterizations were used to study the morphology and crystal structure of the synthesized products. The electrical and gas sensing behaviour of the synthesized and commercial Fe2O3 samples, prepared in the form of thick films, were studied. Though the commercial Fe2O3 powders had lower resistance but it was found that the synthesized Fe2O3 NPs had better gas sensing properties. The underlying mechanisms are discussed in details. The present findings show advantages of Fe2O3 NPs over micro-size particles for gas sensing applications.

Debate remains regarding the timing of laparoscopic cholecystectomy after emergent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis. We hypothesized that patients undergoing early laparoscopic cholecystectomy would have fewer operative complications and a lower conversion rate. This study is a retrospective review of an ERCP database from 2012 to 2016 of adults with a diagnosis of cholangitis secondary to choledocholithiasis who underwent ERCP followed by a laparoscopic cholecystectomy. Patient demographics, ERCP details, timing of operation (72 hours

In this two-part review we present an up-to-date description of different imaging methods available to map the localization of drugs on skin as a complement of established ex-vivo absorption studies. This first part deals with invasive methods which are grouped in two classes according to their underlying principles: i) methods using radioactivity such as autoradiography and ii) mass spectrometry methods such as MALDI and SIMS. For each method, a description of the principle is given along with example applications of imaging and quantifying drug delivery in human skin. Thanks to these techniques a better assessment of the fate of drugs is obtained: its localization on a particular skin structure, its potential accumulation, etc. A critical comparison in terms of capabilities, sensitivity and practical applicability is included that will help the reader to select the most appropriate technique depending on the particular problem to be solved.

The management of advanced gastrointestinal stromal tumors (GISTs) has evolved in the modern era due to the discovery of c-kit mutations and the development of tyrosine kinase inhibitors (TKIs). Until the advent of TKIs such as imatinib, the median survival reported for patients with advanced GIST was 19 months. Although surgery is the treatment of choice for resectable primary GIST, its role in cases of recurrence and metastasis remains to be unclear. This review outlines the potential beneficial role of repeat surgical resection in the multidisciplinary treatment of advanced GIST in the era of TKIs.

Using coherent Raman imaging and deep learning, we have visualized and quantified the pharmacokinetics of drugs in the skin. This spatially and temporally-resolved approach has shed light on the mechanisms of vehicle and drug kinetics.

Iron core&ndash, gold shell (Fe@Au) nanoparticles are prominent for their magnetic and optical properties, which are especially beneficial for biomedical uses. Some experiments were carried out to produce Fe@Au particles with a one-step synthesis method, Ultrasonic Spray Pyrolysis (USP), which is able to produce the particles in a continuous process. The Fe@Au particles were produced with USP from a precursor solution with dissolved Iron (III) chloride and Gold (III) chloride, with Fe/Au concentration ratios ranging from 0.1 to 4. The resulting products are larger Fe oxide particles (mostly maghemite Fe2O3), with mean sizes of about 260&ndash, 390 nm, decorated with Au nanoparticles (AuNPs) with mean sizes of around 24&ndash, 67 nm. The Fe oxide core particles are mostly spherical in all of the experiments, while the AuNPs become increasingly irregular and more heavily agglomerated with lower Fe/Au concentration ratios in the precursor solution. The resulting particle morphology from these experiments is caused by surface chemistry and particle to solvent interactions during particle formation inside the USP system.

We present a detailed analysis of the hybrid fabrication of test parts made from Inconel 718 using two additive-manufacturing (AM) technologies: selective laser melting (SLM) and directed-energy deposition (DED). This combination should allow the manufacturing of larger parts with geometrically complex structures that no other technologies could achieve. However, it is necessary to ensure the consistency of the mechanical properties of such parts. The hybrid SLM/DED parts, as well as the individual SLM and DED processed parts, were evaluated in terms of microstructures and mechanical properties, to understand the mechanisms that control the properties. We introduced a custom solution treatment and aging to dissolve the Laves phase, which was present in the DED part, where it reduced the mechanical properties. For a hybrid part with excellent properties, there must be good bonding between the SLM and DED parts, while the DED process must be adapted to prevent δ-phase precipitation. This new technology has the potential to produce high-added-value metallic products for space applications, that benefit from the properties developed through hybrid AM.

A visible-light-driven photocatalytically active nanocrystalline TiO2 was prepared by surface modification with a cobalt–ascorbic acid complex. The photocatalyst exhibited high activity and excellent chemo-, diastereo-, and stereoselectivities in the aerobic epoxidation of olefins under visible-light irradiation in the absence of a reducing agent. The catalyst proved efficient and could be recycled at least five times.

Commission of errors and conflict between choices might induce behavioral modulations through adjustments in the executive control of behavior and altered patterns of these modulations are detected in neuropsychiatric disorders. We examined the effects of transcranial Direct Current Stimulation (tDCS) applied over the dorsolateral prefrontal cortex (DLPFC) on error- and conflict-induced behavioral modulations. Two separate cohorts of participants performed two clinically relevant tests of executive control, respectively. In the Wisconsin Card Sorting Test (WCST), the relevant rule for matching items frequently changed and therefore participants had to detect these unannounced changes by trial and error and alter their rule-based behavior. In the Stop task, participants had to rapidly respond to a directional go-signal but inhibit their responses when a stop signal appeared after the go-signal. Each participant received tDCS (sham, cathodal or anodal) in three separate sessions. Errors led to a slower response in the next trial (post-error slowing) in both tasks. The tDCS significantly modulated the post-error slowing in both tasks but did not affect the behavioral adjustments induced by the conflict. The modulation of post-error slowing by tDCS were polarity-dependent and also trial specific appearing immediately after errors. In the WCST and Stop task, the post-error slowing may reflect different processes involved in shifting the behavior-guiding rule and adjustments in inhibitory control of responses, respectively, and we found that the effective tDCS polarity differed between the two tasks. Here, we show that in two separate cognitive tasks direct current stimulation of DLPFC significantly modulated error-induced behavioral modulations.

To prevent the evaporation of alkali elements during the calcination of the lead-free piezoelectric K 0.50 Na 0.50 NbO 3 (KNN), lower temperatures for the solid-state synthesis of the KNN from a mixture of Na 2 CO 3 , K 2 CO 3 and Nb 2 O 5 were investigated with a variety of powder-characterization techniques. The collected data suggested 550 °C as a possible low calcination temperature, as well as being sufficiently high for a completed synthesis of the KNN. The XRD and TEM analyses of double-calcined KNN powder at 550 °C revealed nanocrystalline, cube-shaped particles with a perovskite structure, but without noticeable unreacted precursors or secondary phases. Our investigations revealed that the morphology of the calcined powders underwent a dramatic change from small, differently shaped particles at 600 °C/6 h, to fully rounded, large, spherical agglomerates produced at 1000 °C/6 h. To explain this behavior, a mechanism involving the formation of a liquid phase during the reaction of the alkali elements with the moisture and CO 2 in the atmosphere is proposed.

Both the genus and the species Gypsochroa renitidata (Hubner, 1817) are reported for the first time from Iran. Diagnostic characters of the species including figures of the wing and genitalia are presented. The record is confirmed by means of DNA barcoding.

Simple Mn-salen complex was anchored coordinatively to γ-Fe2O3 nanoparticles through amine functionality which provide a new magnetically recoverable nanocatalyst with high oxidation activity and stability. Catalyst characterization was performed using FT-IR, UV-Vis, XRD, EDS, TGA and ICP-AES. TEM image revealed a quasi-spherical structure with size smaller than 20 nm for nanocatalyst. A thermal stability up to around 300 °C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different types of functional groups including olefins, alcohols, saturated hydrocarbons and sulfur containing compounds with n-Bu4NHSO5 (TBAOX) in water under heterogeneous conditions. The salen catalyst proved to be reusable for at least eight times and the oxidant's by-product (n-Bu4NHSO4) could also be recycled.

The incorporation of Co(OAc)2 into ascorbic acid-coated TiO2 nanoparticles easily provided a new heterogeneous visible-light active titania-based photocatalyst (TiO2/AA/Co) which was characterized by different techniques such as FT-IR, XPS, ICP-AES, TGA and TEM. A red-shift of the band-edge and a significant reduction of the band-gap (2.8 eV) were demonstrated by UV-DRS. The as-prepared TiO2/AA/Co nanoparticles possess excellent photocatalytic properties under visible light for the aerobic benzylic C–H oxidation of a structurally diverse set of benzylic alcohols and benzylic hydrocarbons in ethyl acetate as a safe solvent. The spectral results and leaching experiments revealed that the structural integrity of the solid catalyst is well preserved after being reused many times.

Ixiolite-structured ZnTiNb2O8 (ZTN) ceramics were prepared by the simple but effective route of reaction sintering ZnNb2O6 and TiO2 nano powders. The effect of sintering temperature and soaking time on the densification behavior, microstructure evolution and microwave dielectric properties of the synthesized ZTN ceramics were systematically studied. Nano ZnNb2O6 and TiO2 raw materials were mixed, pressed and sintered directly into ceramic bodies without any calcination step involved. The sintered samples were characterized by Field-Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), and microwave dielectric measurements. Single-phase ZnTiNb2O8 ceramics with relative densities up to 97% theoretical density were achieved by sintering at 975–1075 °C. The ixiolite ZTN ceramics reaction sintered at 1050 °C for 3 h exhibited excellent microwave dielectric properties with a dielectric constant ( e r ) = 35.5, quality factor (Q × f0) = 52,500 GHz and a temperature coefficient of resonant frequency ( τ f ) = −60 ppm/°C. These results demonstrate that high-performance ZTN microwave dielectric ceramics can be successfully produced by the simple and efficient reaction-sintering method.

Quantum networks promise to revolutionise computing, simulation, and communication. Light is the ideal information carrier for quantum networks, as its properties are not degraded by noise in ambient conditions, and it can support large bandwidths enabling fast operations and a large information capacity. Quantum memories, devices that store, manipulate, and release on demand quantum light, have been identified as critical components of photonic quantum networks, because they facilitate scalability. However, any noise introduced by the memory can render the device classical by destroying the quantum character of the light. Here we introduce an intrinsically noise-free memory protocol based on two-photon off-resonant cascaded absorption (ORCA). We consequently demonstrate for the first time successful storage of GHz-bandwidth heralded single photons in a warm atomic vapour with no added noise; confirmed by the unaltered photon statistics upon recall. Our ORCA memory platform meets the stringent noise-requirements for quantum memories whilst offering technical simplicity and high-speed operation, and therefore is immediately applicable to low-latency quantum networks.

In addition to the intrinsic toxicity associated with the chemical composition of nanoparticles (NP) and their ligands, biofunctionalized NP can perturb specific cellular processes through NP-cell interactions and induce programmed cell death (apoptosis). In the case of the epidermal growth factor (EGF), nanoconjugation has been shown to enhance the apoptotic efficacy of the ligand, but the critical aspects of the underlying mechanism and its dependence on the NP morphology remain unclear. In this manuscript we characterize the apoptotic efficacy of nanoconjugated EGF as a function of NP size (with sphere diameters in the range 20-80 nm), aspect ratio (A.R., in the range of 4.5 to 8.6), and EGF surface loading in EGFR overexpressing MDA-MB-468 cells. We demonstrate a significant size and morphology dependence in this relatively narrow parameter space with spherical NP with a diameter of approx. 80 nm being much more efficient in inducing apoptosis than smaller spherical NP or rod-shaped NP with comparable EGF loading. The nanoconjugated EGF is found to trigger an EGFR-dependent increase in cytoplasmic reactive oxygen species (ROS) levels but no indications of increased mitochondrial ROS levels or mitochondrial membrane damage are detected at early time points of the apoptosis induction. The increase in cytoplasmic ROS is accompanied by a perturbation of the intracellular glutathione homeostasis, which represents an important check-point for NP-EGF mediated apoptosis. Abrogation of the oxidative stress through the inhibition of EGFR signaling by the EGFR inhibitor AG1478 or addition of antioxidants N-acetyl cysteine (NAC) or tempol, but not trolox, successfully suppressed the apoptotic effect of nanoconjugated EGF. A model to account for the observed morphology dependence of EGF nanoconjugation enhanced apoptosis and the underlying NP-cell interactions is discussed.

The prefrontal cortex is known as a region, most directly involved in cognitive control. One of the most intriguing mysteries in neuroscience is how cognitive control is being implemented. In this thesis, I focused on three prefrontal regions, namely the frontal visual areas (involved in the final stage of cortical processing of saccadic eye movements and visual spatial attention), the frontal pole cortex (involved in multitasking, prospective memory, and exploratory behaviour) and the dorsolateral prefrontal cortex (involved in top-down cognitive control on behavioural modulation during conflict-inducing tasks) and investigated their contributions to cognitive control processes in humans and non-human primates.

Addition of MoO2 (acac)2 to TiO2 coated with ascorbic acid (AA) under ultrasonic agitation resulted in a nanohybrid (TiO2/AA/MoO2) with size ranging between 20–25 nm. The structural and morphological characterization of the as-prepared nanohybrid was carried out by different techniques such as XRD, FT-IR, TGA and transmission electron microscopy (TEM). The catalytic performance of the TiO2/AA/MoO2 nanocomplex in the heterogeneous oxidation of olefins and sulfides using H2O2 in ethanol as a safe solvent was exploited. Our results clearly demonstrated the efficiency, selectivity and oxidative stability of the heterogeneous nanocatalyst providing its effective reusability and removing by-products. The catalytic activity of the TiO2/AA/MoO2 nanocomplex was strikingly different from other nanometer sized metal oxides such as m-ZrO2, MoO3, Fe3O4 and TiO2, as well as their nanocomposites such as TiO2/AA, ZrO2/AA/MoO2, MoO3/AA/MoO2 and Fe3O4/AA/MoO2.

Viral membranes are nanomaterials whose fluidity depends on their composition, in particular, the cholesterol (chol) content. As differences in the membrane composition of individual virus particles can lead to different intracellular fates, biophysical tools capable of sensing the membrane fluidity on the single-virus level are required. In this manuscript, we demonstrate that fluctuations in the polarization of light scattered off gold or silver nanoparticle (NP)-labeled virus-like-particles (VLPs) encode information about the membrane fluidity of individual VLPs. We developed plasmonic polarization fluctuation tracking microscopy (PFTM) which facilitated the investigation of the effect of chol content on the membrane fluidity and its dependence on temperature, for the first time on the single-VLP level. Chol extraction studies with different methyl-β-cyclodextrin (MβCD) concentrations yielded a gradual decrease in polarization fluctuations as a function of time. The rate of chol extraction for individual VLPs showed a broad spread, presumably due to differences in the membrane composition for the individual VLPs, and this heterogeneity increased with decreasing MβCD concentration.