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Direct disposal of used soft electronics into the environment can cause severe pollution to the ecosystem due to the inability of most inorganic materials and synthetic polymers to biodegrade. Additionally, the loss of the noble metals that are commonly used in soft electronics leads to a waste of scarce resources. Thus, there is an urgent need to develop "green" and sustainable soft electronics based on eco‐friendly manufacturing that may be recycled or biodegraded after the devices' end of life. Here an approach to fabricating sustainable soft electronics is demonstrated where the expensive functional materials can be recycled and the soft substrate can be biodegradable. A stretchable agarose/glycerol gel film is used as the substrate, and silver nanowires (AgNWs) are printed on the film to fabricate the soft electronic circuits. The mechanical and chemical properties of the agarose/glycerol gel films are characterized, and the functionality of the printed AgNW electrodes for electrophysiological sensors is demonstrated. The demonstration of the biodegradability of the agarose/glycerol and the recyclability of AgNWs points toward ways to develop sustainable and eco‐friendly soft electronics. [ABSTRACT FROM AUTHOR]

Environmental and health risks posed by microplastics (MPs) have spurred numerous studies to better understand MPs' properties and behavior. Yet, we still lack a comprehensive understanding due to MP's heterogeneity in properties and complexity of plastic property evolution during aging processes. There is an urgent need to thoroughly understand the properties and behavior of MPs as there is increasing evidence of MPs' adverse health and environmental effects. In this perspective, we propose an integrated chemical engineering approach to improve our understanding of MPs. The approach merges artificial intelligence, theoretical methods, and experimental techniques to integrate existing data into models of MPs, investigate unknown features of MPs, and identify future areas of research. The breadth of chemical engineering, which spans biological, computational, and materials sciences, makes it well‐suited to comprehensively characterize MPs. Ultimately, this perspective charts a path for cross‐disciplinary collaborative research in chemical engineering to address the issue of MP pollution. [ABSTRACT FROM AUTHOR]

The article focuses on the appointment of independent directors as a mechanism to reduce the threat of resource diversion and transfer of value from minority shareholders in companies controlled by a dominant shareholder. Topics discussed include the correlation between corporate value and the fraction of the board made up of independent directors; and the ability of independent directors to monitor the actions of controlling shareholders.

The deposition of coatings with hierarchical morphology from hydrophobic and hydrophilic polymers is a common approach for making superhydrophobic and superhydrophilic coatings. The water‐repellent, water‐wicking, and anti‐icing coatings reported here are made from a class of materials called soft dendritic colloids (SDCs). The branched, nanofibrous SDCs are produced in suspension through nonsolvent‐induced phase separation in a turbulent medium. The properties of coatings formed by drying ethanol suspensions of SDCs made of polystyrene, polyvinyl alcohol, and polyester are compared. The highly branched SDC morphology creates entangled, porous coating layers with strong physical adhesion to the substrate due to the multitude of nanofiber sub‐contacts analogous to the "gecko leg effect". Polystyrene SDC coatings show excellent superhydrophobicity but weaker adhesion due to low surface energy. Alternatively, polyvinyl alcohol SDC coatings show superhydrophilicity and strong adhesion from their high surface energy. Two strategies to improve the adhesivity and cohesivity of the SDCs layers are shown effective – use of intertwined networks and of silicone droplet microbinders. The water repulsion, together with the air trapped in the blended superhydrophobic coatings also makes them effective against ice nucleation and adhesion. Finally, these SDCs make thin, flexible, and durable nonwovens with similar properties. [ABSTRACT FROM AUTHOR]

A novel type of mm‐sized silica‐based self‐propelling supraparticles displaying buoyancy‐driven homogeneous vertical oscillatory motion using aqueous hydrogen peroxide (H2O2) as chemical fuel is presented. The supraparticles are prepared via a robust droplet templating technique by drying colloidal suspension droplets containing silica microspheres and catalytic Fe3O4@Pt decorated nanoparticles on a superhydrophobic Cu–Ag surface. Oxygen gas originating from Pt catalyzed decomposition of H2O2 is released and gathered onto the hydrophobic supraparticle surface. This causes buoyancy and uplift of the particle to the surface, where the oxygen bubble is released and the particle descents again, leading to an oscillating process in a very regular fashion. The mechanism of this process is characterized and analyzed here quantitatively by a balance of the gravitational and buoyant forces. The theoretical model of particle movement describes how the particle oscillation period depends on the H2O2 concentration. This novel type of self‐propelling particles could find potential applications in mixing and catalysis, especially due to the high regularity of their periodic movement. [ABSTRACT FROM AUTHOR]

The preparation of fumed silica‐based anisometric supraparticles with well‐defined catalytically active patches suitable for self‐propulsion is presented here. These sub‐millimeter‐sized particles can self‐propel as they contain Pt‐covered magnetite (Fe3O4) nanoparticles, where the Pt can decompose catalytically a "fuel" like H2O2 and thereby propel the supraparticles. By their magnetic properties, the catalytically active nanoparticles can be concentrated in patches on the supraparticle surface. The goal is to obtain robust supraparticles with well‐defined patchiness and long‐time stability during self‐propulsion through evaporation‐induced self‐assembly (EISA) on a superhydrophobic surface. The latter is a major issue as oxygen evolution can lead to the disintegration of the supraparticles. Therefore, enhanced mechanical stability is sought using a number of different additives, where the best results are obtained by incorporating polystyrene microspheres followed by heat treatment or reinforcement with microfibrillated cellulose (MFC) and sodium trisilicate (Na2SiO3). The detailed internal structure of the different types of particles is investigated by confocal micro‐X‐ray fluorescence spectroscopy (CMXRF), which allows for precisely locating the catalytic Fe3O4@Pt nanoparticles within the supraparticles with a resolution in the µm range. The insights on the supraparticle structure, together with their long‐time stability, allow fabricating optimized patchy supraparticles for potential applications in propulsion‐enhanced catalysis. [ABSTRACT FROM AUTHOR]

In 2013, Orlin proved that the max flow problem could be solved in O(nm) time. His algorithm ran in O(nm + m1.94) time, which was the fastest for graphs with fewer than n1.06 arcs. If the graph was not sufficiently sparse, the fastest running time was an algorithm due to King, Rao, and Tarjan. We describe a new variant of the excess scaling algorithm for the max flow problem whose running time strictly dominates the running time of the algorithm by King et al. For graphs in which m = O(nlog n), the running time of our algorithm dominates that of King et al. by a factor of O(loglog n). Moreover, our algorithm achieves this improved performance without reliance on dynamic trees. [ABSTRACT FROM AUTHOR]

A highly controllable and scalable process for fabrication of large amounts of concentrated lignin nanoparticles (LNPs) is reported. These lignin core nanoparticles are formed through flash nanoprecipitation, however, scaling up of the fabrication process requires fundamental understanding of their operational formation mechanism and surface properties. It is shown how a semicontinuous synthesis system with a recirculation loop makes it possible to produce flash precipitated lignin nanoparticles in large amounts for practical applications. The roles of the process parameters, including flow rates and lignin concentration, are investigated and analyzed. The results indicate that the LNPs are formed by a process of continuous burst nucleation at the point of mixing without diffusive growth, which yields nanoparticles of highly uniform size following a modified LaMer nucleation and growth mechanism. This mechanism makes possible facile process control and scale‐up. Effective control of the resulting nanoparticle size is achieved through the initial concentration of lignin in the injected solution. The impressive capability to produce suspensions of any predesigned multimodal distribution is demonstrated. The resulting nanofabrication technique can produce large volumes of concentrated LNP suspensions of high stability and tightly controlled size distributions for biological or agricultural applications. [ABSTRACT FROM AUTHOR]

Background: Postoperative pancreatic fistulas (POPF) grade C represent a rare but feared complication following pancreaticoduodenectomy (PD). They can contribute significantly to postoperative morbidity and mortality. Methods: We performed a retrospective chart review for all patients who had undergone pancreatic head resection between 2007 and 2016 to identify those who suffered from POPF grade C according to the updated definition of the International Study Group of Pancreatic Surgery (ISGPS). Results: A total of 722 patients underwent PD. Twenty‐three patients (3.19%) developed a POPF grade C. Cardiovascular diseases, soft pancreatic texture and main pancreatic duct diameter were identified as risk factors (P <.05). Reoperation was necessary in all affected patients on postoperative day 12 ± 9 on average. Mortality was significantly associated with POPF grade C (P <.05) being present in 39.1% (9/23). Conclusions: POPF grade C after PD remains a serious complication with a high level of morbidity and mortality. Surgical treatment is the sole curative therapy and thus the treatment of choice. [ABSTRACT FROM AUTHOR]

Reconfigurable microdevices are being explored in a range of contexts where their life‐like abilities to move and change shape are important. While much work has been done to control the motion of these microdevices by engineering their geometry and composition, little is known about their dynamics in complex fluid environments with non‐Newtonian rheology. Herein, it is shown how the actuation dynamics of reconfigurable microdevices made by assembly of patchy magnetic microcubes, which are referred to as "microbots," can be modulated by their interactions with the anisotropic viscoelastic environment of a liquid crystal (LC). The free energy arising from the elastic strain of LC and formation of topological defects around the microbots influences their folding dynamics, which can be tuned by tailoring both the far‐field orientation of the LC and the local ordering of the LC at the microbot surfaces. These findings represent a first step toward establishing a general set of design rules to control the dynamics of microbots using complex anisotropic fluids. [ABSTRACT FROM AUTHOR]

We document a striking positive stock price reaction to the announcement of corporate name changes to Internet-related dotcom names. This "dotcom" effect produces cumulative abnormal returns on the order of 74 percent for the 10 days surrounding the announcement day. The effect does not appear to be transitory; there is no evidence of a postannouncement negative drift. The announcement day effect is also similar across all firms, regardless of the firm's level of involvement with the Internet. A mere association with the Internet seems enough to provide a firm with a large and permanent value increase. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the antimicrobial properties of nanocomposite thin TiO2:Cu:Ag films on Pseudomonas putida as a natural isolate and an opportunistic pathogen. Several different methods were used to compare the antibacterial effect of thin TiO2:Cu:Ag layers obtained by radiofrequency magnetron sputter deposition against P. putida: optical density of the bacterial suspension, most probable number of survived cells, dehydrogenase activity inhibition, scanning electron microscopy images, atomic flame absorption spectroscopy, and adenosine triphosphate (ATP) luminescent assay. Optical density measurements and most probable plate count were in agreement and showed a strong bactericidal effect of the as‐deposited and only bacteriostatic effect of the annealed coatings with the same metal content on tested bacteria. As the metal quantity in the medium rises during the first hour of the experiment, it could be suggested that this is the main reason for cell death. ATP‐luminescent assay showed up to 18‐fold reduction of the signal. It was compared with other microbiological and biochemical assays to prove the strong antibacterial effect of nanocomposite thin TiO2:Cu:Ag coatings with the possibilities of medical applications. Protection of medical devices against infections is a significant current challenge raised by an increasing number of medical devices‐associated infections and microbial resistance to conventional antibiotic and multidrug treatments. Deposition of antimicrobial coatings is one of the current approaches to mitigate the problem. [ABSTRACT FROM AUTHOR]

The article presents the author's views regarding the development of multiphasic liquid processes for polymeric and composite materials making. Information about the broad significance and several technology applications, is highlighted. Diversity and versatility of the polymer phase behavior in the innovations for material fabrication, is also emphasized.

Abstract: A class of supercolloidal particles that controllably spin about their central axis in AC electric fields is reported. The rational design of these “microspinners” enables their rotation in a switchable manner, which gives rise to several interesting and programmable behaviors. It is shown that due to their complex shape and discrete metallic patches on their surfaces, these microspinners convert electrical energy into active motion via the interplay of four mechanisms at different electric field frequency ranges. These mechanisms of rotation include (in order of increasing frequency): electrohydrodynamic flows, reversed electrohydrodynamic flows, induced charge electrophoresis, and self‐dielectrophoresis. As the primary mechanism powering their motion transitions from one phenomenon to the next, these microspinners display three directional spin inversions (i.e., from clockwise to anticlockwise, or vice versa). To understand the mechanisms involved, this experimental study is coupled with scaling analyses. Due to their frequency‐switchable rotation, these microspinners have potential for applications such as interlocking gears in colloidal micromachines. Moreover, the principles used to power their switchable motion can be extended to design other types of supercolloidal particles that harvest electrical energy for motion via multiple electrokinetic mechanisms. [ABSTRACT FROM AUTHOR]

In the last two decades, advances in micro- and nanofabrication have enabled the development of a wide variety of active or "self-propelling" microparticles, which convert energy from their environment into directed motion. While these autonomous entities have shown promise for efficient locomotion on the microscale, their practical utility remains unrealized due to their inability to perform multiple useful tasks on demand. From an engineering perspective, the active particle behavior can be encoded on an individual level by tailoring key design elements such as shape, polarizability, surface pattern, and bulk functionality. This feature article focusses on active particles powered by electric and magnetic fields, as these sources of energy allow the particles to: (1) move in several phenomenologically unique ways, (2) respond in a reliable manner to the field parameters, and (3) interact synergistically to enable multiple functions. It is hypothesized how future generations of such particles may remotely harvest and transduce energy to perform several useful tasks such as biosensing and delivering drugs. As a step toward realizing such particles, several new types of active particles are demonstrated. Finally, a perspective on the future directions of this emerging field is provided by discussing current challenges, potential applications as well as future opportunities. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the effect of a new combined method of covering the pancreatic anastomosis or stump with a cyanoacrylate and a falciform patch (CAFP) on the occurrence of postoperative pancreatic fistula (POPF). Methods: Patients undergoing a pancreaticoduodenectomy (PD) or a distal pancreatectomy (DP) were recruited over a period of 12 months. The pancreaticojejunostomy in PD and the stump in DP were sealed with cyanoacrylate glue and wrapped in a falciform patch. Incidence and severity of POPF and associated postoperative complications were retrospectively compared with historical controls of 750 PD and 336 DP at the same institution and with current data from the literature. Results: The new method was applied in 27 PD and 25 DP. The rate of clinically relevant POPF after PD with CAFP was 22.2% compared to 14.4% in historical patients, p = 0.26. The rate of clinically relevant POPF after DP with CAFP was 36% compared to 30% in historical patients, p = 0.65. Conclusion: Sealing the pancreatic anastomosis or stump with a combination of a cyanoacrylate glue and a falciform patch didn't reduce the rate of POPF after major pancreatic resections. [ABSTRACT FROM AUTHOR]

Aim: To examine participation-preference congruence, regional differences in participation-preference congruence, and predictors of whether children with cerebral palsy participate in preferred activities.Method: The sample (n=236) included 148 males and 88 females aged 10 to 13 years, living in Victoria, Australia (n=110), Ontario (n=80), or Quebec (n=46), Canada. Ninety-nine (41.9%) were classed at Gross Motor Function Classification System (GMFCS) level I; 89 (37.7%) at GMFCS level II/III; and 48 (20.3%) at GMFCS level IV/V. Participants completed the Children's Assessment of Participation and Enjoyment and Preferences for Activity of Children questionnaires. Regional comparisons were performed using one-way analyses of variance and factors influencing participation-preference congruence were explored using multiple linear regression.Results: The proportion of children doing non-preferred activities in each activity type was generally low (2-17%), with only one regional difference. Higher proportions were not doing preferred active physical (range 23.2-29.1% across regions), skill-based (range 21.7-27.9% across regions), and social activities (range 12.8-14.5% across regions). GMFCS level was the most important predictor associated with not doing preferred activities.Interpretation: Children with cerebral palsy did not always participate in preferred active physical and skill-based activities. Understanding discrepancies between preferences and actual involvement may allow families and rehabilitation professionals to address participation barriers. [ABSTRACT FROM AUTHOR]

This article presents a study on the formation of anisometric, ellipsoidal supraparticles by evaporation-induced self-assembly from multicomponent colloidal dispersion droplets deposited on a superhydrophobic surface. Performing the formation process on bent surface substrates grants precise control on the shape and spatial orientation of the final dried supraparticles. Due to the V-shaped surfaces providing interfacial blockage, anisotropic evaporation rates occur with respect to the direction of the bending channel. This proportionally leads to inhomogeneous accumulation of fumed silica (FS), used as structure guiding component. Thus, upon the increase of FS-particle interaction via ionic strength (NaCl), this so-formed shell provides enough anisotropic stiffness resulting in predictable droplet deformation with the elongation orientation being perpendicular to the bending axis. The anisotropic evaporation rates were monitored and quantified using an established, empiric kinetic model and taking into account surface geometry. Employing this reliable control of elongation direction and using additional Fe3O4@SiO2 core-shell nanoparticles, anisometric magnetic Janus supraparticles with defined patch position were prepared, which are not accessible on flat surfaces. The results can find application in the controlled, easy to scale up, nanofabrication process of patchy anisometric supraparticles. [ABSTRACT FROM AUTHOR]

Infeasible network flow problems with supplies and demands can be characterized via violated cut-inequalities of the classical Gale-Hoffman theorem. Written as a linear program, irreducible infeasible subsystems (IISs) provide a different means of infeasibility characterization. In this article, we answer a question left open in the literature by showing a one-to-one correspondence between IISs and Gale-Hoffman-inequalities in which one side of the cut has to be weakly connected. We also show that a single max-flow computation allows one to compute an IIS. Moreover, we prove that finding an IIS of minimal cardinality in this special case of flow networks is strongly [ABSTRACT FROM AUTHOR]

This study presents a novel type of mm-sized colloidal supraparticle performing self-propelled oscillating motion that can be programmed on a controlled 3D trajectory. These supraparticles are self-assembled inside drying aqueous colloidal suspension droplets on a superhydrophobic surface. The droplets contain silica microspheres as main colloidal building block and Pt-covered Fe3O4 nanoparticles as catalyst. The supraparticles are rendered patchy by attracting the magnetic catalyst nanoparticles to one side of the droplet during the assembly. Catalytic decomposition of H2O2 leads to vertical motion by buoyancy of formed bubbles. This study comprehensively analyzes this motion in terms of the vertical oscillation frequency that depends on H2O2 'fuel' concentration as well as on the supraparticles density. It is demonstrated that the magnetic functionality can be used to manipulate the particle's trajectory to access nearly any place within the vessel. Furthermore, after binding of α-amylase to the particle surface it is shown that their motion leads to rapid catalytic decomposition of a blue starch-iodine complex within the whole medium. Thus, these functional supraparticles can find versatile applications in a new generation of highly efficient catalysts, microstirrers and self-motile microshuttles that can perform designed tasks while being able to access every point in the liquid in controlled trajectories. [ABSTRACT FROM AUTHOR]

The article focuses on a study that evaluates the efficacy of transfusion service management for patients with sickle-cell disease (SCD). The study is conducted on 83 patients with SCD accompanied with high levels of various cytokines and through the use of questionnaires. The results of the study show the demographics of the patients and several issues related to SCD.

The principles and design of 'active' self-propelling particles that can convert energy, move directionally on their own, and perform a certain function is an emerging multidisciplinary research field, with high potential for future technologies. A simple and effective technique is presented for on-demand steering of self-propelling microdiodes that move electroosmotically on water surface, while supplied with energy by an external alternating (AC) field. It is demonstrated how one can control remotely the direction of diode locomotion by electronically modifying the applied AC signal. The swimming diodes change their direction of motion when a wave asymmetry (equivalent to a DC offset) is introduced into the signal. The data analysis shows that the ability to control and reverse the direction of motion is a result of the electrostatic torque between the asymmetrically polarized diodes and the ionic charges redistributed in the vessel. This novel principle of electrical signal-coded steering of active functional devices, such as diodes and microcircuits, can find applications in motile sensors, MEMs, and microrobotics. [ABSTRACT FROM AUTHOR]

Key Clinical Message A case of intolerable leg pain in pregnancy, caused by Chronic Compartment Syndrome ( CCS), is presented. Increasing amounts of opioids were given throughout the pregnancy. Anesthetical dilemmas and surgery are discussed. In conclusion, early surgery rather than opioids is recommended. [ABSTRACT FROM AUTHOR]

Anisometrische SiO2 ‐ Suprapartikel werden durch einfache Verdunstung einer Dispersion von pyrogenem Siliciumdioxid in Wassertropfen auf einer superhydrophoben Oberfläche erhalten. Die Form der Suprapartikel wird unmittelbar durch die Salzkonzentration (NaCl) kontrolliert. Oberhalb einer Grenzkonzentration werden die Partikel anisometrisch, wie durch Lichtmikroskopie quantifiziert wurde. Das Verfahren kann leicht auf Suprapartikel mit anderen kolloidalen Komponenten übertragen werden. Einfaches Verdunsten von Tropfen einer Suspension von pyrogenem Siliciumdioxid auf superhydrophoben Oberflächen kann anisometrische SiO2 ‐ Suprapartikel liefern. Ihre Form lässt sich durch die NaCl ‐ Anfangskonzentration kontrollieren, wobei ab einer gewissen Schwellenkonzentration anisometrische Strukturen gebildet werden. Mit dieser Methode sind direkt Hybridsuprapartikel zugänglich, indem weitere, auch funktionale, Kolloide eingebaut werden. [ABSTRACT FROM AUTHOR]

Anisometric silica supraparticles are produced by a simple process of evaporation of sessile droplets containing fumed silica deposited on a superhydrophobic substrate. The shape of the supraparticles is directly controlled by the salt (NaCl) concentration, becoming anisometric beyond a threshold concentration, as quantified by light microscopy. This process is easily extended to supraparticles containing further functional colloidal components. [ABSTRACT FROM AUTHOR]

We develop efficient algorithms to solve convex cost flow problems where the underlying graph is a circle, a line, or a tree. Each node i has an associated supply/demand b( i). The cost of sending flow on arc ( i, j) is a piecewise linear convex function f ij defined over [ABSTRACT FROM AUTHOR]

Background: The proportion of octogenarians requiring surgery for pancreatic disease is rapidly growing. This trend will be continued during the next decades, posing a challenge to surgeons and the health care system worldwide. This study aimed to analyze the results of pancreatic surgery in octogenarians in terms of safety and survival based on a cohort of patients at a European high-volume center. Methods: During a 7-year period, 1,705 operations were performed, 76 in patients ≥80 years of age. Data on the octogenarians were retrospectively reviewed and compared to those of the whole collective and to contemporary data from the literature. Primary endpoints were mortality, morbidity, and survival. Results: Overall, 80 % had a malignant disease, and resections were performed in 50 % of all cases. Mortality was 11.8 % and morbidity 72.4 %. There were significantly more medical than surgical complications: 56.6 versus 34.2 %. Pancreatic fistula occurred in 5.3 %, postoperative bleeding in 3.9 %, and delayed gastric emptying in 19.7 %. The median hospital stay was 15 days and the intensive care unit stay 2 days. Mean survival was 28.2 months and in patients with cancer 22.6 months. The 1-, 3-, and 5-year survival rates were 61.4, 31.3, and 18.8 %, respectively. Conclusions: Despite high mortality and morbidity rates, surgery remains the only chance for cure in most octogenarians with pancreatic disease. Careful patient selection is the key to success and improved long-term survival in this group, which will represent a substantial fraction of the population in the near future. [ABSTRACT FROM AUTHOR]

This study addresses the optical and electrical properties of ZnO thin films doped with Al, V and Nb (ZnO:Al, ZnO:V and ZnO:Nb, respectively) deposited by r.f. magnetron sputtering in Ar atmosphere. The films are deposited on glass substrates without heating and heated at 100 °C, 150 °C and 275 °C. The optical spectra of transmittance and reflectance are measured and the optical band gap of the films is determined. The different films have band gap values in the range of 3.37-3.57 eV. The films have about 90% transmittance and their resistivity is in the range of 8.5-2.0 mΩ.cm. The influence of doping elements on the optical and electrical characteristics of the obtained thin films is discussed (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The present work concerns the electrochemical deposition of aluminum-doped ZnO nanostructured thin films on SnO2:F-covered glass substrates. Doped with Al nanostructured ZnO (ZnO:Al) films are obtained by an electrochemical process using a three-electrode potentiostatic system with a saturated calomel electrode as reference electrode, in aqueous solution containing ZnCl2, KCl, and Al2(SO4)3. The influence of the deposition parameters on the structural properties of the obtained ZnO:Al layers is investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). Energy-dispersive X-ray analysis (EDAX) is applied for measurement of the Al content in the films. The SEM micrographs and AFM pictures show that the ZnO:Al films consist of nanograins with a shape of walls. The XRD spectra demonstrate the characteristic (100), (002), (101), (110), and (103) reflections of the ZnO. The influence of the Al concentration on the IR reflectance spectra and the haze ratio of ZnO:Al thin films are presented and discussed. [ABSTRACT FROM AUTHOR]

In this paper we report results of fabrication of ordered ZnO nanorods (NRs) or nanowalls (NWs) electrochemically deposited on different highly conductive substrates. The following types of conductive substrates have been used: (i) highly doped p-type multi-crystalline Si, and (ii) copper thin plates. The influence of a seeding Ag layer deposited on multi-Si substrates on the growth of ZnO NRs has been studied as well. It is observed that morphology of the deposited ZnO structures depends strongly on the type of the substrate used. It is found that ZnO structures with different shapes, such as NRs, nanotubes or NWs can be grown on top of highly conductive substrates used in this work. It is observed that optical reflection of the deposited layers depends on the substrate used as well as on the time of the electrochemical deposition of ZnO layers. It was found that: (i) for ZnO NWs/Cu structures, diffused reflection exhibit strong enhancement compared to pure Cu substrate; (ii) in case of ZnO NRs/Si structures reflection is decreased compared to that for pure Si substrate. Possible applications of ZnO NRs or NWs-based structures for the processing of advanced Si-based solar cells are discussed. [ABSTRACT FROM AUTHOR]

The pseudoflow algorithm for solving the maximum flow and minimum cut problems was devised in Hochbaum (2008). The complexity of the algorithm was shown in (2008) to be O( nm log n). Chandran and Hochbaum, (2009) demonstrated that the pseudoflow algorithm is very efficient in practice, and that the highest label version of the algorithm tends to perform best. Here, we improve the running time of the highest label pseudoflow algorithm to O( n3) using simple data structures and to O( nm log ( n2/ m)) using the dynamic trees data structure. Both these algorithms use a new form of Depth-First-Search implementation that is likely to be fast in practice as well. In addition, we give a new simpler description of the pseudoflow algorithm by relating it to the simplex algorithm as applied to the maximum preflow problem defined here. The interpretation of the generic pseudoflow algorithm as a simplex-like algorithm for the maximum preflow problem motivates the pseudoflow algorithm and highlights differences between the pseudoflow algorithm and the preflow-push algorithm of Goldberg and Tarjan. © 2012 Wiley Periodicals, Inc. NETWORKS, 2013 [ABSTRACT FROM AUTHOR]

Background Social participation with friends fosters development of meaningful relationships, life skills and psychosocial well-being. Youths with cerebral palsy (CP) face challenges to establishing social relationships with friends. The aim of this study was to explore whether social participation with friends differs among youths with CP based on their self-perceived competence as a friend. Methods A total of 135 youths with CP, 13-21 years old (mean age 16 years, 50% were male), completed the measures Fulfillment in Social Roles and Children's Assessment of Participation and Enjoyment. Youths were assigned to high, middle and low groups defined by their self-perceived competence as a friend. Differences among the three groups in the number, total frequency and enjoyment of activities done with friends was examined by Kruskal-Wallis one-way analyses of variance. Post hoc analysis of significant effects was performed using a Mann-Whitney U-test or Kolmogorov-Smirnov test. Results The number (χ2= 17.07, d.f. = 2, P < 0.001) and total frequency (χ2= 18.35, d.f. = 2, P < 0.001) of activities done with friends differed based on youths' self-perceived competence as a friend. Youths with high self-perceived competence as a friend did the greatest number of activities and participated most often with friends. Youths with low self-perceived competence did the fewest activities and participated least often with friends. No differences were found in the enjoyment of activities done with friends among the three groups (χ2= 1.86, d.f. = 2, P > 0.05). Conclusions For youths with CP, the number and frequency of activities done with friends differed based on self-perceived competence as a friend, but not enjoyment of activities. The results suggest a positive link between social participation and self-perceived competence. Healthcare providers have a role to support youths' efforts to engage with friends by enhancing community opportunities, developing and providing interventions in natural social environments and incorporating peer support into service delivery. [ABSTRACT FROM AUTHOR]

To test a model of child, family, and service determinants of intensity of participation in leisure and recreational activities by children with cerebral palsy (CP). Participants were 288 children with CP, age range 6 to 12 years (mean 9y 8mo, SD 2y), and their parents from seven children's hospitals. The sample comprised 166 (57.6%) males and 122 (42.4%) females, and between 40 (13.9%) and 74 (25.7%) children in each of the five levels of the Gross Motor Function Classification System. Children completed the Children's Assessment of Participation and Enjoyment by interview. Parents completed the Pediatric Outcomes Data Collection Instrument, Family Environment Scale, Coping Inventory, Measure of Processes of Care, and two questionnaires. Structural equation modeling was used to test the model. Fit statistics indicated a good model fit. The model explains 32% of the variance in intensity of participation. Path coefficients ( p≤0.05) indicate that higher gross motor function, higher enjoyment, more effective adaptive behavior, younger age, and higher family activity orientation are associated with higher intensity of participation. The path between services and participation was not significant. Intensity of participation of children with CP is influenced by multiple child and family determinants. Children's gross motor function and behavior in life situations are important for participation; knowledge of activities the child and family enjoy has implications for opportunities for participation. Professionals are encouraged to address priorities for leisure and recreation identified by children with CP and their families. [ABSTRACT FROM AUTHOR]

Melatonin plays a protective role in experimental acute pancreatitis (AP) because of its antioxidative, antiinflammatory, and immunomodulatory effects. This study presents the first data on the dynamic changes of endogenous melatonin in the early phase of human AP. Morning (08:00 hr) serum melatonin concentrations were measured by ELISA in 75 patients with AP for the first 5 days after the onset of pain. According to the Atlanta classification, 26 patients suffered a mild AP (MAP). The other 49 developed a severe AP (SAP). Median melatonin concentrations of healthy volunteers were used as a control. Median melatonin level in healthy controls was 18.5 pg/mL. Levels of melatonin were significantly higher in the first 24 hr after onset of disease in patients with MAP compared to those with SAP, 51.2 versus 8.7 pg/mL ( P = 0.01). Melatonin values were the same in MAP and SAP during the remainder of the study period. Melatonin concentrations during the first 24 hr after the onset of pain in younger patients (<35 yrs old) were significantly higher than levels in older patients (>35 yrs): 73 versus 8.7 pg/mL ( P = 0.01). No correlation existed between melatonin levels and the following parameters: gender, etiology (biliary versus alcohol induced), and histological findings (edematous versus necrotizing versus infected necrosis). High endogenous melatonin serum levels in the first 24 hr after the onset of AP played a protective role and favoured a mild course of the disease in humans, especially in young patients. [ABSTRACT FROM AUTHOR]

Aim Participation in home, extracurricular, and community activities is a desired outcome of rehabilitation services for children and young people with cerebral palsy (CP). The purpose of this study was to investigate the effect of age and gross motor function on participation among children and young people with CP. Method Five hundred participants (277 males, 223 females) were grouped by age and Gross Motor Function Classification System (GMFCS) level. There were 291 children aged 6 to 12 years and 209 young people aged 13 to 21 years. There were 128 participants in GMFCS level I, 220 in levels II/III, and 152 in levels IV/V. Participants completed the Children’s Assessment of Participation and Enjoyment to measure number of activities (diversity) and how often they were performed (intensity) in the past 4 months. Results Children had higher overall participation diversity and intensity than young people ( p<0.001). Children and young people in GMFCS level I had the highest overall participation, followed by children and young people in levels II/III and IV/V. Children had higher participation in recreational ( p<0.001) but not formal (such as team sports or clubs) or physical activities. Children ( p<0.01) and young people ( p<0.001) in level I had the highest participation in physical activities; diversity and intensity were generally low. Interpretation The findings provide evidence of the effect of age and gross motor function on participation of children and young people with CP. Low participation in physical activities may have implications for fitness and health, especially for children and young people in GMFCS levels IV and V. [ABSTRACT FROM AUTHOR]

Background. This study aimed to analyse the most common current indications for total pancreatectomy (TP) at a high-volume pancreas center. Method. Prospectively collected data on indications and short-term outcome of all TP's performed from January 2004 until June 2008 were analysed. Results. The total pancreatectomies (TP) were 63, i.e., 6.7% of all pancreatic procedures (n = 948). Indications for TP were classified into 4 groups: tumors of advanced stage, n = 23 (36.5%), technical problems due to soft pancreatic tissue, n = 18 (28.6%), troubles due to perioperative surgical complications, n = 15 (23.8%), and therapy-resistant pain due to chronic pancreatitis, n = 7 (11.1%). Surgical complications occurred in 23 patients (36.5%). The mortality in elective TP was 6.25%. Median postoperative stay was 21 days. Mortality, morbidity and the other perioperative parameters differed substantially according to the indication for pancreatectomy. Conclusion. Total pancreatectomy is definitely indicated for a limited range of elective and emergency situations. Indications can be: size or localisation of pancreatic tumor, trouble, technical difficulties and therapy-refractory pain in chronic pancreatitis. A TP due to perioperative complications (troubles) after pancreatic resections is doomed by extremely high morbidity and mortality and should be avoided. [ABSTRACT FROM AUTHOR]

Background Understanding the needs of families of children and youth with cerebral palsy (CP) is important for family-centred services. The aims of this study were to identify: (1) differences in the number and types of family needs expressed by parents based on the age and gross motor function level of their children with CP; (2) the most frequent family needs; and (3) needs that differ on gross motor function level. Methods A total of 501 parents (77.6% mothers) of children and youth with CP completed a modified version of a Family Needs Survey and a demographic questionnaire. Children's gross motor function level was classified using the Gross Motor Function Classification System. Results Total number of family needs differed based on gross motor function level (P < 0.001) but not age. Parents of children/youth who use wheeled mobility expressed the highest number of family needs, while parents of children/youth who walk without restrictions expressed the fewest needs. Family needs for Information (P = 0.001), Support (P = 0.001), Community Services (P < 0.001) and Finances (P < 0.001) differed based on children's gross motor function level. Over 50% of parents expressed family needs for information on current and future services, planning for the future, help in locating community activities and more personal time. Parents of children and youth who use wheeled mobility were more likely to express the need for help in paying for home modifications, equipment, services and locating sitters, respite care providers and community activities. Conclusions The gross motor function of children/youth with CP has implications for collaboration with families to identify needs and co-ordinate services. Health professionals have a role to assist families with information needs and locating community services and leisure activities. Family needs for future planning suggest that health professionals should assist families to prepare for key periods in the lives of their children with CP. [ABSTRACT FROM AUTHOR]