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Affective disorders occur frequently during and/or following pregnancy, at prevalence of 7% and 9%, respectively, [1,2]. Presence of such illness heightens the morbidity and mortality of mothers an...

The risks, consequences and severity of wildland fires are well-known. Hence, the demand for timely, high-quality fire information in the least amount of time possible and the subsequent intimation to concerned authorities would help in scaling down the loss of life and property. This paper discusses a WSN system which collects data using multiple sensors to monitor temperature, humidity, smoke and oxygen levels in several spots in a forest environment. The forest would be divided into square-shaped clusters for monitoring, each containing a sensor system. The localisation of the node would be done using satellite communication to reduce coverage holes and ensure maximum range with the least latency. This node would communicate data to a monitoring station with its location and send alerts according to the sensed thresholds breached based on the novel logic algorithm. This paper describes the overall structure of the sensing system, detection and prediction algorithms, topology of the WSN, localisation techniques and an insight into a suggested drone-based mitigation system to localise the fire.

The aim of this study was to assess the feasibility of flattening filter-free (FFF) photon beams in hybrid intensity-modulated radiation therapy (H-IMRT) and hybrid volumetric modulated arc therapy (H-VMAT) for left-sided whole-breast radiation therapy with a boost volume (RT) using a hypofractionated dose regimen. RT plans of 25 patients with left-sided early-stage breast cancer were created with H‑IMRT and H‑VMAT techniques under breath-hold conditions using 6‑MV FFF beams. In hybrid techniques, three-dimensional conformal radiotherapy (3DCRT) plans were kept as base-dose plans for the VMAT and IMRT plans. In addition, H‑IMRT in step-and-shoot mode was also calculated to assess its achievability with FFF beams. All hybrid plans achieved the expected target coverage. H‑VMAT showed better coverage and homogeneity index results for the boost target (p

This study discusses the operation of a Homogeneous Charge Compression Ignition (HCCI) engine using simulated biogas and diethyl ether (DEE) as the primary and secondary fuels respectively. Performance, emission and combustion parameters are measured for various biogas flow rates (8–16 litre/min), composition (50 to 100% methane), intake temperatures (35–80 °C) and loads (20 to 90% of full load). A comparison of injecting DEE at the intake port (port injection) and 7 cm upstream (manifold injection) is also presented. It was demonstrated that at high flow rates and/or with high methane content, biogas can effectively substitute DEE and provide up to 60% of the total energy input. However, the use of lower biogas flow rates and methane fraction resulted in better thermal efficiency (as high as 26%) as well as lower HC emissions. HCCI operation offered simultaneously low NOx (

In this paper, we employ bibliometric analysis to empirically analyse the research on social entrepreneurship published between 1996 and 2017. By employing methods of citation analysis, document co-citation analysis, and social network analysis, we analyse 1296 papers containing 74,237 cited references and uncover the structure, or intellectual base, of research on social entrepreneurship. We identify nine distinct clusters of social entrepreneurship research that depict the intellectual structure of the field. The results provide an overall perspective of the social entrepreneurship field, identifying its influential works and analysing scholarly communication between these works. The results further aid in clarifying the overall centrality features of the social entrepreneurship research network. We also examine the integration of ethics into social entrepreneurship literature. We conclude with a discussion on the structure and evolution of the social entrepreneurship field.

Plasmonic-photonic metallo-dielectric structures have attracted recent research interests due to their novel optical properties. Au–SiO2 based photonic structures have been built and have shown promising applications for example, as SERS substrates. However, due to the lack of control over the constraints in the various stages of conventional colloidal crystal templating approach, monolayer metallo-dielectric inverse opal structures have not been widely reported. In this work, a 2D hexagonal inverse opal (IO) photonic structure of Au nanoparticles (NP) embedded in a SiO2 matrix is constructed using a new strategy. Here in, a binary Au–SiO2 sol was infiltrated into the accommodative interstices of 2D self-assembled polystyrene (PS) spheres in an air-water interface. Effective removal of the PS spheres by chemical method resulted in Au–SiO2 IO structures. Optical properties of these structures show interesting plasmonic-photonic coupling. When they are used as substrates for Raman signal enhancement of crystal violet, they show better enhancement than either Au nanoparticles aggregates or Au–SiO2 non-photonic structures. The Au–SiO2 IO structures were also used to perform Raman spectroscopy analysis of astaxanthin rich shrimp oil, a novel value-added product extracted from the water used in shrimp processing. The surface enhanced Raman spectra showed the presence of favourable esterified form of astaxanthin in shrimp oil.

The wake evolution measured downstream of multi-megawatt wind turbines located in flat and complex terrains are described here. These high-resolution measurements at full-scale Reynolds number conditions are made with an instrumented drone that is equipped with a suite of sensors and detail the characteristics of the mean flow and turbulent kinetic energy in the evolving wake. Reynolds decomposition yields the nature of turbulent fluctuations in surface layer, and this decomposition is used to detail the turbulence statistics, degree of anisotropy and friction velocity. These measurements are shown to be suited for the further development of three-dimensional wake models that are currently under intensive development.

Concave shape with variable size target volume makes treatment planning for the breast/chest wall a challenge. Conventional techniques used for the breast/chest wall cancer treatment provided better sparing of organs at risk (OARs), with poor conformity and uniformity to the target volume. Advanced technologies such as intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) improve the target coverage at the cost of higher low dose volumes to OARs. Novel hybrid techniques present promising results in breast/chest wall irradiation in terms of target coverage as well as OARs sparing. Several published data compared these technologies for the benefit of the breast/chest wall with or without nodal volumes. The aim of this article is to review relevant data and identify the scope for further research in developing optimal treatment plan for breast/chest wall cancer treatment.

A facile and versatile polyol mediated solvo-thermal process using zinc acetate has been adopted for the synthesis of mesoporous ZnO nanomaterials having novel morphologies. Polyols used in this study, i.e. ethylene glycol (EG) and polyethylene glycols (PEG) of molecular weight 200 and 400, not only act as solvents but also as structure directing agents. The synthesis using EG leads to the formation of novel square bipyramidal zinc glycolate intermediate, which upon thermal treatment is converted into a nanocrystalline (NC) wurtzite ZnO structure, preserving the square bipyramidal morphology. Zinc glycolate upon hot water treatment (∼85 °C), results in the formation of NC wurtzite ZnO having a bicone morphology. However, when the synthesis is carried out by replacing EG with PEG-200 or 400, NC wurtzite ZnO having spherical morphologies have been directly isolated. In the case of PEG-200, the NC ZnO spheres displayed radially oriented nanorod features on the surface. A mechanism of formation of these ZnO morphologies is proposed. The synthesized ZnO materials have been used as catalysts for the photodegradation of crystal violet dye under UV-B and UV-C irradiation. The catalytic behavior of the ZnO samples is explained based on their porosity, crystallinity, and microstructure.

The measurements of the near (less than three rotor diameter) and far wakes (unto eleven rotor diameter) in a utility scale wind farm are described. The high spatial and temporal resolution measurements are made with an instrumented drone that is equipped with a suite of sensors. These measurements detail for the first time at full-scale Reynolds number conditions, the evolution and breakdown of tip vortices that are characteristic of the near wake and the turbulent mixing and entrainment of more energised flow that are distinctive in the far wake. Comparisons of these measurements to recently developed wake prediction models highlights how these measurements can support further model development.

A novel initiative towards the digital image processing technique by the application of histogram of oriented gradients (HOG) feature descriptor using the OpenCV library coded with the High-level programming language Python, booted with the help of Raspberry Pi microcontroller fitted with a RaspiCam to capture moving images of objects passing under it has been presented in this paper. The project utilizes image samples in top-view which are used to set predefined models containing a great number of motion variations for identification of humans entering a room through a door or gate. Pair of Passive Infra-Red (PIR) sensors has been used to instruct the system to capture images of incoming or outgoing objects that cross it. This method of image detection combined with a sensor feedback has been used along with an ability to send data via bluetooth to local servers for security or record purposes.

Recent research interests in geometrical isomers of astaxanthin (AST) are motivated by their metabolic activities in aquatic animals and human. It has been established that cis-isomers of AST are selectively absorbed in human plasma during the metabolic process; however, exact absorption mechanism is still unclear. Hence, a detailed investigation of the structural and optical properties of geometrical isomers of AST is required. Among the techniques available for the study of AST and other carotenoids, Raman spectroscopy has been much acclaimed. Raman spectra have been shown to be influenced by the electronic and mechanical confinement effects arising from the conjugated polyene chain of carotenoids. In this work, we present Raman studies of geometrical isomers of AST, along with their optical absorption characteristics. Geometrical isomers of AST were prepared by heating all trans-AST in solution form, and the isomers were separated using high performance liquid chromatography. Optical absorption spectra of cis-isomers of AST showed hypsochromic shifts in the main absorption band and formation of new bands at lower wavelengths. A detailed Raman spectral analysis performed on the cis-isomers of AST showed new modes which have not been observed and accounted for so far. In addition, we demonstrate that the electronic and mechanical confinement effects in the polyene chain of AST play an important role in the Raman spectra of geometrical isomers of AST. It is anticipated that this work will demonstrate that Raman spectroscopy is an important diagnostic tool in distinguishing and identifying the geometrical isomers of AST. Copyright © 2014 John Wiley & Sons, Ltd.

The present work describes a novel synthesis approach for titanium dioxide coated SBA-16 type silica mesoporous microspheres. Anatase TiO2 coated SBA-16 type silica microspheres which have interesting photocatalytic properties offers the viability of the adsorption and photocatalytic degradation of dyes in water. SBA-16 type silica microspheres were synthesized by a sol–gel method with Pluronic F127 employed as a structure directing agent (template) and TEOS (tetraethyl orthosilicate) as the silica source. Surface modification of the SBA-16 type silica microspheres through titanium dioxide nanocrystals resulted in a titanium dioxide coated SBA-16 silica microsphere composite material. The prepared composite material was characterized by SEM, TEM, EDX, nitrogen adsorption-desorption analysis and Raman spectroscopy studies. The characterization results show that the material possesses relatively high surface area (223.48–233.08 m2/g), a periodically ordered porous nature, and anatase nanocrystalline titanium dioxide coating. Photocatalytic degradation tests show significant improvement in the photodegradation of crystal violet with increased titanium dioxide coating; further confirming the material's viability for photocatalytic degradation of light sensitive hazardous organic compounds in polluted waters.

Two-dimensional (2D) inverse opal (IO) TiO2 films, synthesized by colloidal crystal templating, such as polystyrene (PS) spheres, are particularly interesting because of their potential applications in sensors, solar cells, and electrochromic devices. For these applications, high crystallinity is essential for device performance. Usually, to achieve the IO structure with high crystallinity, the PS opal template is first removed by calcination at a temperature of ∼400 °C, and subsequently to crystallize amorphous TiO2, a temperature higher than 400 °C is needed. This results in cracks and collapse of the macroporous framework. Furthermore, this route is limited to thermally stable substrates, such as glass, which is a significant drawback as the increasing development of technologies and modern electronics requires the design of inexpensive, lightweight, and efficient optoelectronic devices on flexible substrates. In order to circumvent these problems, we developed a ‘dynamic-hard-template’ infiltration strategy for the fabrication of large-area crack-free nanocrystalline (NC) anatase 2D-TiO2 IO films on rigid transparent conducting substrates and on ITO coated flexible polyethyleneterephthalate (ITO/PET) substrates, by using various sizes of PS spheres. According to this strategy, first a dynamic opal 2D film of PS spheres is self-assembled on the surface of water, followed by the infiltration of preformed anatase TiO2 nanoparticle sol from the bottom into the PS opal crystal as the guest material, thus eliminating the need for high temperature crystallization. The obtained floating PS/TiO2 opal composite film is deposited on ITO-coated glass and ITO/PET substrates. An optimized low temperature chemical method is adopted to remove the PS template to yield NC anatase 2D-TiO2 IO films. The films obtained on ITO/PET substrates were successfully used as an active electrode in the fabrication of a flexible electrochromic device.

The objective of this study is to check the feasibility of in vivo rectal dose measurement in intensity-modulated radiotherapy (IMRT) and CyberKnife treatments for carcinoma prostate. An in-house pelvis phantom made with bee's wax was used in this study. Two cylindrical bone equivalent materials were used to simulate the femur. Target and other critical structures associated with carcinoma prostate were delineated on the treatment planning images by the radiation oncologist. IMRT treatment plan was generated in Oncentra Master Plan treatment planning system and CyberKnife treatment plan was generated in Multiplan treatment planning system. Dose measurements were carried out in phantom and in patient using Gafchromic EBT3 films. RIT software was used to analyze the dose measured by EBT3 films. The measured doses using EBT3 films were compared with the TPS-calculated dose along the anterior rectal wall at multiple points. From the in-phantom measurements, it is observed that the difference between calculated and measured dose was mostly within 5%, except for a few measurement points. The difference between calculated and measured dose in the in-patient measurements was higher than 5% in regions which were away from the target. Gafchromic EBT3 film is a suitable detector for in vivo rectal dose measurements as it offers the possibility of analyzing the dose at multiple points. In addition, the method of extending this in vivo rectal dose measurement technique as a tool for patient-specific quality assurance check is also analyzed.

The purpose of this planning case report is to share the perceived dosimetric benefits of innovative hybrid volumetric modulated arc therapy (h-VMAT) for bilateral breast cancer radiotherapy in two patients with synchronous bilateral breast cancer. Two patients with early bilateral breast cancer after breast conservation surgery and adjuvant chemotherapy were planned for bilateral breast radiotherapy. On the planning computed tomography (CT) dataset, bilateral breast planning treatment volume (PTV) and organs at risk (OARs) were delineated using standard guidelines. Using the same structure set, volumetric modulated arc therapy (VMAT) and h-VMAT plans were generated and compared dosimetrically. The h-VMAT showed comparable target coverage, conformity and homogeneity while sparing of both lungs and heart were better. The dose to heart was reduced with h-VMAT, with a V25Gy and V5Gy of 3.2 & 22.3% for h-VMAT versus 11.6 & 84.9% for the VMAT plan. Similarly, the dose to the total lung was better in h-VMAT with a V20Gy and V5Gy of 12.1 & 46.2 versus 19.9 & 83.3% for VMAT. Overall the results indicate a better sparing of lung and heart at low doses with h-VMAT. Long-term clinical follow-up will give us more insight about the dosimetric benefits of these innovative techniques.

Astaxanthin is a carotenoid naturally found in microbial organisms, microalgae, and many crustaceans. Its consumption has led to beneficial effects such as pigmentation of marine animals, and it favorably addresses several human health issues as a result of its high important antioxidant property. Several companies produce synthetic trans-astaxanthin for dietary purposes in aquaculture, where it is mainly used for pigmentation. It is known that trans-astaxanthin manifests itself as a monomer in organic solvents, as aggregates in aqueous solutions of organic solvents, or as crystalline solids. These forms display unique optical and structural properties, which have an impact on biological systems. In this work, we report on detailed Raman investigations, in conjunction with optical absorption spectroscopy, of monomer, aggregates, and crystalline forms of trans-astaxanthin. The Raman and optical absorption spectroscopic investigations of trans-astaxanthin aggregates were performed as a function of time, showing the formation of card-packed aggregates after 2 h, and head-to-tail aggregates after 24 h in a 10% acetone–water astaxanthin solution. For the crystalline trans-astaxanthin, a pointwise Raman mapping evidenced the presence of two distinct crystal structures. The Raman modes of these crystal structures (A and B) were correlated with the intermolecular interactions present in chloroform solvated (AXT-Cl) and unsolvated (un-AXT) trans-astaxanthin single crystals. Both crystal structure A and the card-packed aggregates have similar intermolecular π stacking interactions as AXT-Cl. The crystal structure B and the head-to-tail aggregates showed linear chain features as in un-AXT. This work also clearly demonstrates that Raman spectroscopy is a powerful tool to distinguish the crystal structures present in crystalline powder of trans-astaxanthin. Copyright © 2012 John Wiley & Sons, Ltd.

Controlled WO 3 morphologies, such as nanorods and octahedral structures, were synthesized by the hydrothermal technique using sulfate salts based structure directing agents (SDAs). The role of the sulfate salts’ cation in controlling the shape, size and phase of WO 3 nanomaterials was investigated by choosing sulfate salts whose cations are from d-bloc elements (FeSO 4 , (NH 4 ) 2 Fe(SO 4 ) 2 , CoSO 4 , CuSO 4 , ZnSO 4 ), an alkaline earth metal (MgSO 4 ) and a non-metal ((NH 4 ) 2 SO 4 ). In addition chloride (MnCl 2 ) and acetate (Zn(CH 3 CO 2 ) 2 ) anion based SDAs were also used in order to clarify the role of sulfate ions in the growth of WO 3 nanostructures. We controlled the pH of the reaction medium with oxalic acid. The obtained WO 3 samples were investigated by SEM, micro-Raman, and XRD. At pH = 1, the WO 3 samples exhibit novel superstructures consisting of aligned hexagonal nanorods, whereas at pH = 5.25, novel twin octahedral morphology with a cubic structure is obtained. The results demonstrate that the phase and morphology change is influenced by the pH and both the anion and the cation of the SDA. A growth mechanism for the obtained novel WO 3 morphologies is presented.

The aerodynamic characteristics of wakes in complex terrain have a profound impact on the energy yield of wind farms and on the fatigue loads on wind turbines in the wind farm. In order to detail the spatial variations of the wind speed, wind direction, and turbulent kinetic energy (TKE) in the near-wake, comprehensive drone-based measurements at a multi-megawatt (MW) wind turbine that is located in complex terrain have been conducted. A short-time Fourier transform (STFT)-based analysis method is used to derive time-localized TKE along the drone's trajectory. In upstream and in the near-wake, the vertical profiles of wind speed, wind direction, and TKE are detailed. There is an increase in the TKE from upstream to downstream of the wind turbine, and whereas, the characteristic microscale length scales increase with increasing height above the ground upstream of the turbine, in the near-wake the microscale lengths are of constant, smaller magnitude. The first-ever measurements of the pressure field across a multi-MW wind turbines rotor plane and of the tip vortices in the near-wake are also reported. It is shown that the pitch between subsequent tip vortices, which are shed from the wind turbines blades, increases in the near-wake as the wake evolves. These details of the near-wake can have an important effect on the subsequent evolution of the wake and must be incorporated into the three-dimensional (3D) field wake models that are currently under intensive development.

Background context Intramedullary spinal cord arteriovenous malformations (AVMs) are rare and have an unfavorable prognosis. We report our experience of treating three symptomatic patients with stereotactic radiosurgery (SRS). The standard treatment for these lesions are embolization or microsurgical resection. There are only a few reports of efficacy of radiosurgery in these cases. Purpose To study the efficacy of radiosurgery in intramedullary spinal cord AVM patients, who failed or refused conventional treatment. Study setting This study reports the results of SRS in 3 cases of intramedullary spinal cord AVMs. Patient sample Three symptomatic patients diagnosed with intramedullary spinal cord AVMs. Two patients underwent embolization previously and one was newly diagnosed. Outcome measures The AVM obliteration was assessed by yearly high-resolution magnetic resonance imaging (MRI). Clinical examination was carried out every 6 months. Methods Three symptomatic patients with intramedullary spinal cord AVMs were treated with SRS using the cyberknife system from January 2010 to May 2011. All the three patients presented with acute neurologic symptoms. Two patients were treated previously with embolization. As per protocol, patients underwent a plain computed tomography (CT), CT angiography, high-resolution MRI, and conventional spinal angiography for radiotherapy planning. The mean target volume was 4.05 cc. The prescribed dose was 21 Gy in three fractions on consecutive days. No special immobilization was done during treatment. Continuous image guidance of the treated area was done using the specialized spine tracking software. Follow-up was done by yearly clinical examination and high-resolution spine MRI after SRS. Results Mean follow-up was 36 months. Follow-up MRI revealed absence of flow voids, suggesting complete obliteration of the AVM in two patients, with significant improvement in neurologic and functional symptoms. The third patient did not show any clinical improvement or deterioration. There was no incidence of hemorrhage after SRS in any patient and the treatment was well tolerated without any significant complications. Conclusions Stereotactic radiosurgery for intramedullary spinal AVMs appears to be well tolerated and effective in selected cases.

Recent developments in the synthesis of mesoporous nanocrystalline titanium oxide (TiO2) have opened up several new opportunities in the construction of efficient photovoltaic (PV) cells. In this chapter, we describe principles involved in the construction of organic photovoltaic cell and the influence of the main parameters for the case of PEDOT:PSS polymers. At the outset different architectures of the PEDOT:PSS photovoltaics are described and later incorporation of the TiO2 nanoparticles in their architectures is carefully considered. A special attention is given to the technique of photovoltaic cell preparation and the basic principles of their functionality. A significant emphasis has been devoted to the current–voltage characteristics of photovoltaic cells, thus constructed with and without nanocrystalline TiO2, as well as to the ways it can be further improved. We also describe the synthesis of mesoporous TiO2 nanoparticles using titanium alkoxides as precursor and polyethylene glycol (PEG) of different molecular mass as templating agent to induce mesoporosity. The interaction of PEG with titanium alkoxides in polar and nonpolar solvents was studied in detail by macro-Raman spectroscopy, solid-state NMR and MALDI-TOF-MS. The removal of PEG as well as the crystallization process was obtained by hot water treatment at low temperature (90 °C). The mesoporosity was retained after further calcination up to 500 °C. Porosity, morphology, and microstructures of the resultant products were characterized by SEM, nitrogen adsorption–desorption measurements, micro-Raman spectroscopy and XRD. The mesostructure of the TiO2 particles facilitates enhanced transport of electrons, resulting in improved photovoltaic efficiency. Influence of TiO2 nanoparticles on the photovoltaic efficiency of the ITO/PEDOT:PSS/fluorine copolymers/polythiophene:TiO2/Al architecture is analyzed. Influence of TiO2 NP on the principal parameters of different PV architecture is discussed. The analysis of the efficiency is performed using both experimental and theoretical quantum chemical approach.

A dosimetric comparison of linear accelerator (LA)-based (BrainLAB) and robotic radiosurgery (RS) (CyberKnife) systems for acoustic schwannoma (Acoustic neuroma, AN) was carried out. Seven patients with radiologically confirmed unilateral AN were planned with both an LA-based (BrainLAB) and robotic RS (CyberKnife) system using the same computed tomography (CT) dataset and contours. Gross tumour volume (GTV) was contoured on post-contrast magnetic resonance imaging (MRI) scan [planning target volume (PTV) margin 2 mm]. Planning and calculation were done with appropriate calculation algorithms. The prescribed isodose in both systems was considered adequate to cover at least 95% of the contoured target. Plan evaluations were done by examining the target coverage by the prescribed isodose line, and high- and low-dose volumes. Isodose plans and dose volume histograms generated by the two systems were compared. There was no statistically significant difference between the contoured volumes between the systems. Tumour volumes ranged from 380 to 3,100 mm(3). Dose prescription was 13-15 Gy in single fraction (median prescribed isodose 85%). There were no significant differences in conformity index (CI) (0.53 versus 0.58; P = 0.225), maximum brainstem dose (4.9 versus 4.7 Gy; P = 0.935), 2.5-Gy volume (39.9 versus 52.3 cc; P = 0.238) or 5-Gy volume (11.8 versus 16.8 cc; P = 0.129) between BrainLAB and CyberKnife system plans. There were statistically significant differences in organs at risk (OAR) doses, such as mean cochlear dose (6.9 versus 5.4 Gy; P = 0.001), mean mesial temporal dose (2.6 versus 1.7 Gy; P = 0.07) and high-dose (10 Gy) volume (3.2 versus 5.2 cc; P = 0.017). AN patients planned with the CyberKnife system had superior OAR (cochlea and mesial temporal lobe) sparing compared with those planned with the Linac-based system. Further evaluation of these findings in prospective studies with clinical correlation will provide actual clinical benefit from the dosimetric superiority of CyberKnife.

A 'dynamic hard-template' infiltration strategy for crack-free large-area synthesis of 2D WO3 inverse opal (IO) films on ITO substrates using a wide range of sizes of sacrificial PS spheres is reported. Thus prepared WO3 IO films were successfully used as an active electrode in the fabrication of an electrochromic device.