bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Air-Stability and Performance of Bulk Heterojunction Polymer Solar Cells Using Solvent Engineered Hole Selective Interlayer
Authors: Xu Binrui , Sai-Anand Gopalan , Jeong Hyun-Min , Kim Sae-Wan , Kim Ju-Seong , Kwon Jin-Beom , Kang Shin-Won
Published: July 2018

In bulk heterojunction polymer solar cells (BHJ-PSCs), poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) is the most commonly used hole selective interlayer (HSIL). However, its acidity, hygroscopic nature, and the use of indium tin oxide (ITO) etching can degrade the overall photovoltaic performance and the air-stability of BHJ-PSCs. Solvent engineering is considered as a facile approach to overcome these issues. In this work, we engineered the HSIL using ethanol (ET) treated PEDOT:PSS to simultaneously enhance the photovoltaic performance properties and air-stability of the fabricated devices. We systematically investigated the influence of ET on the microstructural, morphological, interfacial characteristics of modified HSIL and photovoltaic characteristics of BHJ-PSCs. Compared with the BHJ-PSC with pristine PEDOT:PSS, a significant enhancement of power conversion efficiency (~17%) was witnessed for the BHJ-PSC with PEDOT:PSS-ET (v/v, 1:0.5). Consequently, the BHJ-PSC with PEDOT:PSS-ET (v/v, 1:0.5) as HSIL exhibited remarkably improved air-stability.
Stress Concentration and Mechanical Strength of Cubic Lattice Architectures
Authors: Lohmuller Paul , Favre Julien , Piotrowski Boris , Kenzari Samuel , Laheurte Pascal
Published: July 2018

The continuous design of cubic lattice architecture materials provides a wide range of mechanical properties. It makes possible to control the stress magnitude and the local maxima in the structure. This study reveals some architectures specifically designed to reach a good compromise between mass reduction and mechanical strength. Decreased local stress concentration prevents the early occurrence of localized plasticity or damage, and promotes the fatigue resistance. The high performance of cubic architectures is reported extensively, and structures with the best damage resistance are identified. The fatigue resistance and S–N curves (stress magnitude versus lifetime curves) can be estimated successfully, based on the investigation of the stress concentration. The output data are represented in two-dimensional (2D) color maps to help mechanical engineers in selecting the suitable architecture with the desired stress concentration factor, and eventually with the correct fatigue lifetime.
Acute and transient psychotic disorders in a rapidly developing country, State of Qatar
Authors: Shaltout Taher , Bener Abdulbari , Al Abdullah Majid , Al Mujalli Zahra , Shaltout Hany
Published: July 2018

Background. Little is known about acute and transient psychotic disorders, which is a diagnostic group, introduced with International Classification of Disease, 10th revision. It is an interesting area of research receiving a lot of attention. Objective. The aim of the study was to find the incidence of acute and transient psychotic disorders in the population and determine its sociodemographic features in the State of Qatar. Design. This is a retrospective descriptive study. Setting. The study was conducted in the Department of Psychiatry of the Rumaillah Hospital, Hamad Medical Corporation, Doha, Qatar. Methods. All Qatari, non-Qatari Arabs, and expatriate patients who were hospitalized with psychotic disorders in the inpatient wards or treated in the outpatient clinics of the Department of Psychiatry over a 7-year period were enrolled in the study. Data were collected from the medical records of patients. The study was conducted from August 1, 1996, to January 1, 2004, amongst the patients with acute and transient psychotic disorders. The diagnostic classification of definite psychotic disorders was made in accordance with criteria based on the International Classification of Disease, 10th revision (ICD-10). Results. A total of 174 patients were treated during a 7-year period. Among them, 69% were males and 31% females. No cases were found in children aged less than 15 years. The highest frequency (43.7%) was found in the early adulthood (16–29 years of age). The incidence of acute and transient psychotic disorders was higher in the expatriates (66.7%). More than half (63.8%) of the patients were employed. Most of the cases (35.6%) had acute schizophrenia-like psychotic disorders (F23.2). There was no statistically significant difference in the frequency of acute and transient psychotic disorders between males and females, Qatari and non-Qatari Arabs, and single and married. Conclusion. The study found markedly lower incidence rate of acute and transient psychotic disorders in females than males. The highest frequency was found in the early adulthood (16–29 years). No cases were found in children aged less than 15 years. It is important to find ways to promote healthier lifestyles in this population in order to prevent the onset of psychotic disorders.
The approach of medical students towards studies of the humanities and social sciences
Authors: Jakušovaitė Irayda , Blaževičienė Aurelija
Published: July 2018

Objective. To analyze the attitudes of the medical students from Kaunas University of Medicine, Krakow Jagiellonian University, and St. Petersburg State University towards the studies of the humanities and social sciences. Materials and methods. The survey was carried out in three universities (Kaunas University of Medicine, Krakow Jagiellonian University, and St. Petersburg State University) during 2004– 2005. The questionnaire for the investigation was developed based on R. D. Stenberg’s works on the ways of knowledge-, practice-, and personality-oriented thinking. Results. After the analysis of students’ attitudes towards the importance of the disciplines of ethics, philosophy, sociology, and psychology at the universities of Kaunas, Krakow, and St. Petersburg, important differences have been found among them. Students gave the highest priority to ethics in their profession. Answering the question, “Are philosophical studies important in medical studies,” statistically significant differences appeared among Krakow, Kaunas, and St. Petersburg universities. Students of all the universities agreed that sociology and psychology studies were important for their future profession. Conclusions. Having estimated the opinions of medical students’ attitudes towards the importance of the humanities and social sciences, we may state that the students of Krakow and St. Petersburg universities more often agreed that ethics and philosophy were important for their studies. The importance of psychology science was emphasized by the students of all universities, and the students of Kaunas University of Medicine and St. Petersburg State University agreed more often that the discipline of sociology was important for the future studies.
A comparison of the effectiveness of the early enteral and natural nutrition after pancreatoduodenectomy
Authors: Grižas Saulius , Gulbinas Antanas , Barauskas Giedrius , Pundzius Juozas
Published: July 2018

The role of postoperative supplementary enteral nutrition after gastrointestinal surgery is controversial. Therefore, a randomized clinical trial with attempts to address the question of plenitude of routine application of postoperative enteral feeding on rate of postoperative complications following pancreatoduodenectomy was performed. Sixty patients undergoing pancreatoduodenectomy were blindly randomized into two groups: 30 patients in the first group received early enteral nutrition (EEN), while 30 patients in the second group were given early natural nutrition (ENN). The complications were evaluated according to definition criteria. All complications were further subdivided into infectious and noninfectious complications. Our data showed that patients in EEN group gained a larger amount of energy in kcal a day during the first five days after surgery in comparison to ENN group. There was a higher rate of postoperative complications in ENN group (53.3% vs 23.3%, P=0.03). This difference occurred mainly due to the higher incidence of infectious complications in ENN group (46.7% vs 16.7%, P=0.025). There were six cases of bacteriemia in this group of patients, while only one case was observed in EEN group (6 (20.0%) vs 1 (3.3%), P=0.1). The overall risk for the development of any type of infectious complication was 1.5 times higher in ENN group. In conclusion, this study suggests that supplementary postoperative enteral nutrition helps to decrease the rate of infectious complications in patients undergoing pancreatoduodenectomy, especially in those with a plasma albumin level of less than 34.5 g/L and/or ASA class III or higher, since natural nutrition is insufficient in this ca.
Analysis of antibiotic consumption and microorganism resistance changes
Authors: Galinytė Daiva , Mačiulaitis Romaldas , Budnikas Vytautas , Kubilius Darius , Varanavičienė Birutė , Vitkauskienė Astra , Jokimas Juozas , Jodkonis Laimis
Published: July 2018

Objective. The main goal of this study was to evaluate the variation of antibiotic consumption and relation between antibiotic consumption and microorganism resistance. Material and methods. This analysis was performed in one of Lithuanian tertiary hospitals. The defined daily dose (DDD) analysis was performed to express drug consumption per every 100 occupied bed days (OBDs) for single units in clinical departments. Average of DDD/100 OBDs was estimated for 2004–2007, and mean values were compared among all four years. The relation between the number of surgical operations and antibiotic consumption in surgery departments was analysed. E. coli and K. pneumoniae resistance for four years (2004–2007) was determined. Moreover, the relation between microorganism resistance and variation of antibiotic consumption was determined. Data were analysed by descriptive and comparative statistics (by Mann–Whitney test for nonparametric criteria and Spearman correlation). Results. Comparing the DDD/100 OBD data during 2004–2007 revealed a statistically significant increase in piperacillin and tazobactam (877.50%), metronidazole (114.00%), cefuroxime (77.31%), meropenem (47.55%), cefoperazone and sulbactam (173.11%) consumption. The increased usage of these antibiotics was determined in surgery department too. However, the increased number of surgical operations cannot be the only reason of the growing antibiotic consumption. Results revealed a statistically significant decrease in ofloxacin use from 2006 to 2007 (93.94%). E. coli resistance to ampicillin (from 49.80% to 56.60%), ampicillin and sulbactam (from 25.50% to 39.20%), cefuroxime (from 7.40% to 10.10%), ciprofloxacin (from 4.20% to 12.50%), gentamicin (from 11.40% to 13.20%) and K. pneumoniae resistance to ampicillin and sulbactam (from 45.40% to 56.40%), cefuroxime (from 34.00% to 39.10%), ciprofloxacin (from 5.50% to 10.50%), gentamicin (from 32.00% to 35.80%) increased. A statistically significant positive correlation between quinolone consumption and K. pneumoniae resistance to ciprofloxacin was determined (r=1, P<0.05). Conclusions. In 2004–2007, the usage of piperacillin and tazobactam, metronidazole, cefuroxime, meropenem, cefoperazone, and sulbactam increased. In 2006–2007, ofloxacin consumption decreased. The changes in other antibiotic usage were statistically insignificant. In 2004–2007, E. coli and K. pneumoniae resistance to ampicillin and sulbactam, cefuroxime, ciprofloxacin, gentamicin and E. coli resistance to ampicillin increased. A statistically significant positive correlation between quinolone consumption and K. pneumoniae resistance to ciprofloxacin was determined.
Apoptosis: Activation and Inhibition in Health and Disease
Authors: Solano-Gálvez Sandra Georgina , Abadi-Chiriti Jack , Gutiérrez-Velez Luis , Rodríguez-Puente Eduardo , Konstat-Korzenny Enrique , Álvarez-Hernández Diego-Abelardo , Franyuti-Kelly Giorgio , Gutiérrez-Kobeh Laila , Vázquez-López Rosalino
Published: July 2018

There are many types of cell death, each involving multiple and complex molecular events. Cell death can occur accidentally when exposed to extreme physical, chemical, or mechanical conditions, or it can also be regulated, which involves a genetically coded complex machinery to carry out the process. Apoptosis is an example of the latter. Apoptotic cell death can be triggered through different intracellular signalling pathways that lead to morphological changes and eventually cell death. This is a normal and biological process carried out during maturation, remodelling, growth, and development in tissues. To maintain tissue homeostasis, regulatory, and inhibitory mechanisms must control apoptosis. Paradoxically, these same pathways are utilized during infection by distinct intracellular microorganisms to evade recognition by the immune system and therefore survive, reproduce and develop. In cancer, neoplastic cells inhibit apoptosis, thus allowing their survival and increasing their capability to invade different tissues and organs. The purpose of this work is to review the generalities of the molecular mechanisms and signalling pathways involved in apoptosis induction and inhibition. Additionally, we compile the current evidence of apoptosis modulation during cancer and Leishmania infection as a model of apoptosis regulation by an intracellular microorganism.
Evaluation of Surface Characteristics and Hemocompatibility on the Oxygen Plasma-Modified Biomedical Titanium
Authors: Chiang Hsi-Jen , Chou Hsin-Hua , Ou Keng-Liang , Sugiatno Erwan , Ruslin Muhammad , Waris Rahmat Abd , Huang Chiung-Fang , Liu Chung-Ming , Peng Pei-Wen
Published: July 2018

Oxygen plasma with different treatment powers and durations was utilized to modify the biomedical pure titanium (Ti) surface in the present study. The superficial, microstructural and biological properties of the plasma-oxidized samples were investigated using the electron microscopy, X-ray photoemission spectroscopy, grazing incidence X-ray diffractometer, contact angle goniometer and blood clotting time assay. During different treatment powers and durations, the island-like nanostructural rutile-TiO2 layer and dimple-like nanostructural rutile-TiO2 layer were generated on the surfaces of the plasma-oxidized samples, respectively. It was also found that the plasma-oxidized sample with a rough oxide layer resulted in the formation of a higher wettability. Moreover, the blood clotting time assay indicated that the plasma-oxidized samples exhibited the adhesion behaviors of red blood cells. As the Ti surface underwent plasma oxidation at 280 W for 30 min, it not only generates a rough nanostructural rutile-TiO2 layer, but also presents an excellent hemocompatibility. Therefore, these findings demonstrate that oxygen plasma modification is a potential approach to promote the hemocompatibility of biomedical pure Ti surface.
Effect of Rolling Reduction on Microstructure and Property of Ultrafine Grained Low-Carbon Steel Processed by Cryorolling Martensite
Authors: Yuan Qing , Xu Guang , Liu Sheng , Liu Man , Hu Haijiang , Li Guangqiang
Published: July 2018

A novel method of cryorolling martensite for fabricating ultrafine grained low-carbon steel with attractive strength was proposed. The results indicate that ultrafine-grain structured steel could be manufactured by cryorolling and the subsequent annealing of martensite. The mean ferrite size of 132.0 nm and the tensile strength of 978.1 MPa were obtained in a specimen with a reduction of 70% in thickness. There were peak value and valley value in the strength and grain size of ferrite with the increase of reduction from 50% to 80%, respectively. The further growth of ferrite grain at 80% reduction is attributed to the heavier distortion energy at large reduction, which activates the secondary recrystallization of ferrite. Furthermore, the distribution of ferrite grains became more uniform with increasing of reduction from 50% to 70%. Additionally, the amount of lamellar dislocation cell substructure increased with the reduction at liquid nitrogen temperature.
Influence of Stress State on the Mechanical Impact and Deformation Behaviors of Aluminum Alloys
Authors: Rodriguez-Millan Marcos , Garcia-Gonzalez Daniel , Rusinek Alexis , Arias Angel
Published: July 2018

Under impact loading conditions, the stress state derived from the contact between the projectile and the target, as well as from the subsequent mechanical waves, is a variable of great interest. The geometry of the projectile plays a dertermining role in the resulting stress state in the targeted structure. In this regard, different stress states lead to different failure modes. In this work, we analyze the influence of the stress state on the deformation and failure behaviors of three aluminum alloys that are commonly used in the aeronautical, naval, and automotive industries. To this purpose, tension-torsion tests are performed covering a wide range of stress triaxialities and Lode parameters. Secondly, the observations from these static tests are compared to failure mode of the same materials at high impact velocities tests with the aim of analysing the role of stress state and strain rate in the mechanical response of the aluminum plates. Experimental impacts are conducted with different projectile geometries to allow for the analysis of stress states influence. In addition, these experiments are simulated by using finite element models to evaluate the predictive capability of three failure criteria: critical plastic deformation, Johnson-Cook, and Bai-Wierzbicki.
Comprehensive Simulations for Ultraviolet Lithography Process of Thick SU-8 Photoresist
Authors: Zhou Zai-Fa , Huang Qing-An
Published: July 2018

Thick SU-8 photoresist has been a popular photoresist material to fabricate various mechanical, biological, and chemical devices for many years. The accuracy and precision of the ultraviolet (UV) lithography process of thick SU-8 depend on key parameters in the set-up, the material properties of the SU-8 resist, and the thickness of the resist structure. As feature sizes get smaller and pattern complexity increases, accurate control and efficient optimization of the lithography process are significantly expected. Numerical simulations can be employed to improve understanding and process design of the SU-8 lithography, thereby allowing rapid related product and process development. A typical comprehensive lithography of UV lithography of thick SU-8 includes aerial image simulation, exposure simulation, post-exposure bake (PEB) simulation, and development simulation, and this article presents an overview of the essential aspects in the comprehensive simulation. At first, models for the lithography process of the SU-8 are discussed. Then, main algorithms for etching surface evolvement, including the string, ray tracing, cellular automaton, and fast marching algorithms, are introduced and compared with each other in terms of performance. After that, some simulation results of the UV lithography process of the SU-8 are presented, demonstrating the promising potential and efficiency of the simulation technology. Finally, a prospect is discussed for some open questions in three-dimensional (3D) comprehensive simulation of the UV lithography of the SU-8.
Human Pathogenic Paecilomyces from Food
Authors: Moreira Danielly C. , Oliveira Manoel M. E. , Borba Cintia M.
Published: July 2018

Paecilomyces spp. and Byssochlamys spp. are heat-resistant fungi important to industry because they can cause food and beverage spoilage, incurring economic loss. The consequences of food or beverage fungal colonization is the loss of nutritional value, structure and taste, and the possibility of producing toxic secondary metabolites that may result in medical problems. Furthermore, these fungi can infect animals and humans and it is unknown if contaminated foods may be fomites. P. variotii is the principal agent of food spoilage or contamination and it is most frequently associated with human hyalohyphomycosis with clinical manifestations including peritonitis, cutaneous and disseminated infections, among others. Byssochlamys spp. had not been identified as a cause of systemic infection until the case of a dog with a fungal infection, after immunosuppressive therapy. P. variotii has clinical importance because it causes severe infection in immunosuppressed patients and also because the number of immunocompetent infected patients is increasing. This review draws attention to the ability of these species to grow at high temperatures, to colonize food products, and to cause human disease.
Variations of Major Product Derived from Conversion of 5-Hydroxymethylfurfural over a Modified MOFs-Derived Carbon Material in Response to Reaction Conditions
Authors: Wang Zhenhua , Chen Qianwang
Published: July 2018

In recent years, the conversion of 5-hydroxymethylfurfural (HMF) into 5-ethoxymethylfurfural (EMF) and ethyl levulinate (EL) has become an attractive biomass transformation route due to their potential applications in the energy and chemical industries. In this study, we have developed an effective method to prepare a catalyst for this reaction. Sulfonic-acid-functionalized carbon nanomaterials (C-SO3H), prepared from the direct pyrolysis of Metal-Organic Frameworks (MOFs) precursor Cu-benzene-1,3,5-tricarboxylate (Cu-BTC) followed by acidification with sulfuric acid, show excellent catalytic activity with a total yield higher than 90%. It is interesting that, different from the previous catalysts, a different major product—EMF or EL—can be selectively obtained by controlling the reaction temperature and time.
Controlling the 3D Electromagnetic Coupling in Co-Sputtered Ag–SiO2 Nanomace Arrays by Lateral Sizes
Authors: Zhang Fan , Guo Shuang , Liu Yang , Chen Lei , Wang Yaxin , Gao Renxian , Zhu Aonan , Zhang Xiaolong , Zhang Yongjun
Published: July 2018

Ag–SiO2 nanomace arrays were prepared on a two-dimensional ordered colloidal (2D) polystyrene sphere template by co-sputtering Ag and SiO2 in a magnetron sputtering system. The lateral size of the nanomaces and the distance between the neighbor nanomaces were controlled by adjusting the etching time of the 2D template. The nanomaces were composed of SiO2-isolated Ag nanoparticles, which produced surface-enhanced Raman scattering (SERS) enhancement, and 3D hot spots were created between the neighbor nanomaces. When the distance between the nanomaces was sufficiently large, triangle-shaped nanostructures on silicon substrate were observed, which also contributed to the enhancement of the SERS signals. The finite-difference time-domain (FDTD) method was used to calculate the electromagnetic field distributions in the Ag–SiO2 nanomace arrays, which generated physical reasons for the change of the SERS signals.
“Chocolate” Gold Nanoparticles—One Pot Synthesis and Biocompatibility
Authors: Roy Chowdhury Neelika , Cowin Allison J. , Zilm Peter , Vasilev Krasimir
Published: July 2018

The chemical synthesis of nanoparticles can involve and generate toxic materials. Here, we present for the first time, a one pot direct route to synthesize gold nanoparticles (AuNPs) using natural cacao extract as both a reducing and stabilizing agent. The nanoparticles were characterized by UV-visible spectroscopy (UV-VIS), dynamic light scattering (DLS), and transmission electron microscopy (TEM); and have excellent biocompatibility with human primary dermal fibroblasts.
Multi-Band Up-Converted Lasing Behavior in NaYF4:Yb/Er Nanocrystals
Authors: Peng Ya-Pei , Lu Wei , Ren Pengpeng , Ni Yiquan , Wang Yunfeng , Yan Peiguang , Zeng Yu-Jia , Zhang Wenfei , Ruan Shuangchen
Published: July 2018

Random lasers have attracted great interests and extensively investigation owing to their promising applications. Here, we explored unambiguously the multi-band up-converted random lasing from NaYF4:Yb,Er nanocrystals (NCs). NaYF4:Yb,Er NCs exhibit high effective up-conversion luminescence when they are excited by continuous wave 980 nm laser. We investigated a planar microcavities approach wherein the NaYF4:Yb,Er NCs showed up-converted lasing behavior. The optical pumping of NaYF4:Yb,Er NCs by 980 nm pulsed laser excitation exhibited multi-band lasing. The NaYF4:Yb,Er NCs showed multi-band lasing emission with a line width of 0.2 nm at 540 nm and 0.4 nm at 660 nm. This research promotes potential application in bioimaging and biomedical fields.
Zinc Deficiency among Lactating Mothers from a Peri-Urban Community of the Ecuadorian Andean Region: An Initial Approach to the Need of Zinc Supplementation
Authors: Narváez-Caicedo Camila , Moreano Gabriela , Sandoval Bernardo A. , Jara-Palacios Miguel Á.
Published: July 2018

Zinc is an important mineral for biological and physiological processes. Zinc deficiency (ZD) is one of the most common micronutrient deficiencies worldwide and a crucial determinant of pregnancy outcomes and childhood development. Zinc levels and the zinc supplementation rate among lactating women have not been assessed neither in Ecuador nor in the Andean region. We conducted a pilot study including 64 mothers of infants between eight days to seven months old from a primary care center located in Conocoto, a peri-urban community of Quito, Ecuador. The mothers were interviewed and a fasting blood sample was taken to determine plasma zinc levels. The prevalence of ZD was calculated and compared with the prevalence of ZD among Ecuadorian non-pregnant non-lactating women, and the sample was analysed considering zinc supplementation during pregnancy. The prevalence of ZD among the participants was 81.3% (95% CI: 71.7–90.9), higher than the reported among non-pregnant non-lactating women (G2 = 18.2; p < 0.05). Zinc supplementation rate was 31.2%. No significant differences were found comparing the groups considering zinc supplementation. The insights obtained from this study encourage extending studies to document zinc levels and its interactions among breastfeeding women in areas with a high prevalence of ZD in order to determine the need of zinc supplementation.
Bacterial Lipopolysaccharide Increases Serotonin Metabolism in Both Medial Prefrontal Cortex and Nucleus Accumbens in Male Wild Type Rats, but Not in Serotonin Transporter Knockout Rats
Authors: Korte-Bouws Gerdien A. H. , Van Heesch Floor , Westphal Koen G. C. , Ankersmit Lisa M. J. , Van Oosten Edwin M. , Güntürkün Onur , Korte S. Mechiel
Published: July 2018

It is well known that bacterial lipopolysaccharides (LPS) both increases proinflammatory cytokines and produces sickness behavior, including fatigue and anhedonia (i.e., the inability to experience pleasure). Previously, we have shown that intraperitoneally (i.p.) administered LPS increased extracellular monoamine metabolite levels in the nucleus accumbens (NAc) and medial prefrontal cortex (mPFC), which was completely, or at least partly, prevented by pretreatment with a triple reuptake inhibitor that also blocks the serotonin (5-HT) transporter (SERT). This suggests indirectly, that LPS may enhance SERT transporter activity, and consequently, increase removal of 5-HT from the synaptic cleft, and increase metabolism of 5-HT. In the present study, we focus more specifically on the role of SERT in this increased metabolism by using rats, that differ in SERT expression. Therefore, the effects of an intraperitoneal LPS injection on extracellular concentrations of 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were investigated by in vivo microdialysis in the NAc and mPFC of wild type (SERT+/+), heterozygous (SERT+/−) and knockout (SERT−/−) rats. Here, we show that LPS-induced 5-HIAA formation in male rats, is significantly increased in SERT+/+ rats in both the NAc and mPFC, whereas this increase is partly or totally abolished in SERT+/− and SERT−/− rats, respectively. Thus, the present study supports the hypothesis that systemic LPS in male rats increases SERT function and consequently enhances 5-HT uptake and metabolism in both the NAc and mPFC.
Investigating the Mechanism of Horseradish Peroxidase as a RAFT-Initiase
Authors: Danielson Alex P. , Van-Kuren Dylan Bailey , Bornstein Joshua P. , Kozuszek Caleb T. , Berberich Jason A. , Page Richard C. , Konkolewicz Dominik
Published: July 2018

A detailed mechanistic and kinetic study of enzymatically initiated RAFT polymerization is performed by combining enzymatic assays and polymerization kinetics analysis. Horseradish peroxidase (HRP) initiated RAFT polymerization of dimethylacrylamide (DMAm) was studied. This polymerization was controlled by 2-(propionic acid)ylethyl trithiocarbonate (PAETC) in the presence of H2O2 as a substrate and acetylacetone (ACAC) as a mediator. In general, well controlled polymers with narrow molecular weight distributions and good agreement between theoretical and measured molecular weights are consistently obtained by this method. Kinetic and enzymatic assay analyses show that HRP loading accelerates the reaction, with a critical concentration of ACAC needed to effectively generate polymerization initiating radicals. The PAETC RAFT agent is required to control the reaction, although the RAFT agent also has an inhibitory effect on enzymatic performance and polymerization. Interestingly, although H2O2 is the substrate for HRP there is an optimal concentration near 1 mM, under the conditions studies, with higher or lower concentrations leading to lower polymerization rates and poorer enzymatic activity. This is explained through a competition between the H2O2 acting as a substrate, but also an inhibitor of HRP at high concentrations.
Breathable and Flexible Piezoelectric ZnO@PVDF Fibrous Nanogenerator for Wearable Applications
Authors: Kim Minji , Wu Yuen Shing , Kan Edwin C. , Fan Jintu
Published: July 2018

A novel breathable piezoelectric membrane has been developed by growing zinc oxide (ZnO) nanorods on the surface of electrospun poly(vinylidene fluoride) (PVDF) nanofibers using a low-temperature hydrothermal method. Significant improvement in the piezoelectric response of the PVDF membrane was achieved without compromising breathability and flexibility. PVDF is one of the most frequently used piezoelectric polymers due to its high durability and reasonable piezoelectric coefficient values. However, further enhancement of its piezoelectric response is highly desirable for sensor and energy-harvester applications. Previous studies have demonstrated that piezoelectric ceramic and polymer composites can have remarkable piezoelectric properties and flexibility. However, devices made of such composites lack breathability and some present health risks in wearable applications for containing heavy metals. Unlike other piezoelectric ceramics, ZnO is non-toxic material and has been widely used in many applications including cosmetics. The fabrication of ZnO@PVDF porous electrospun membrane involves a simple low-temperature ZnO growth in aqueous solution, which does not weaken the polarization of PVDF created during electrospinning in the high electric field.
Oil-Water Separation of Electrospun Cellulose Triacetate Nanofiber Membranes Modified by Electrophoretically Deposited TiO2/Graphene Oxide
Authors: Naseem Saba , Wu Chang-Mou , Xu Ting-Zhen , Lai Chiu-Chun , Rwei Syang-Peng
Published: July 2018

Recycled waste industrial cellulose triacetate (TAC) film, which is one of the key materials in polarizers, was used to produce nanofiber membranes by electrospinning and synergistic assembly with graphene oxide (GO) and titanium dioxide (TiO2) for oil-water separation. In this study, GO and TiO2 coated by an electrophoretic deposition method introduced super hydrophilicity onto the recycled TAC (rTAC) membrane, with enhanced water permeability. The results indicate that when the outermost TiO2 layer of an asymmetric composite fiber membrane is exposed to ultraviolet irradiation; the hydrophilicity of the hydrophilic layer is more effectively promoted. Moreover, this coating could efficiently repel oil, and demonstrated robust self-cleaning performance during the cycle test, with the aid of the photocatalytic properties of TiO2. The rTAC membrane of networked hydrophobic fibers could also increase the speed of the filtrate flow and the water flux of the oil-water emulsion. The permeate carbon concentration in the water was analyzed using a total organic carbon analyzer. Incorporation of TiO2/GO onto the rTAC membrane contributed greatly towards enhanced membrane hydrophilicity and antifouling performance. Therefore, the novel TiO2/GO/rTAC asymmetric composite fiber has promise for applications in oil-water separation.
Diffuse Attenuation Coefficient Retrieval in CDOM Dominated Inland Water with High Chlorophyll-a Concentrations
Authors: Gomes Ana Carolina Campos , Bernardo Nariane , Carmo Alisson Coelho do , Rodrigues Thanan , Alcântara Enner
Published: July 2018

The kd(490) is a vertical light attenuation coefficient and an important parameter for water quality. The kd estimates are often based on empirical and semi-analytical algorithms, designed for oceanic and coastal waters. However, there is a lack of information about the performances of these models to inland waters dominated by chromophoric dissolved organic matter (CDOM). Therefore, to contribute to this investigation, nine empirical models based on the blue-to-green and blue-to-red ratios and chlorophyll-a (Chl-a) concentration were evaluated, as well as three semi-analytical models using bands from the Operational Land Imager (OLI)/Landsat-8. The errors (mean absolute percentage error, MAPE > 80%) presented by the empirical models confirmed that the blue-to-green ratio failed in retrieving kd(490) in an environment dominated by CDOM. Similar failures occurred with the models using the Chl-a concentration (MAPE ~60%) as input. A semi-analytical approach showed the lowest error (MAPE = 41.04%) in the estimate of the inherent optical properties for complex waters in order to reduce the errors above. After retrieval of kd(490) using the semi-analytical model, seasonal patterns were observed, and high values of kd(490) were detected in the dry season possibly due to the increase of the concentration of the optically-significant substances (OSS).
Characteristic and Driving Factors of Aerosol Optical Depth over Mainland China during 1980–2017
Authors: Qin Wenmin , Liu Ying , Wang Lunche , Lin Aiwen , Xia Xiangao , Che Huizheng , Bilal Muhammad , Zhang Ming
Published: July 2018

Since the reform and opening up of China, the increasing aerosol emissions have posted great challenges to the country’s climate change and human health. The aerosol optical depth (AOD) is one of the main physical indicators quantifying the atmospheric turbidity and air pollution. In this study, 38-years (1980–2017) of spatial and temporal variations of AOD in China were analyzed using AOD records derived from MODIS atmosphere products and the MERRA-2 dataset. The results showed that the annual mean AOD values throughout China have gone through an increasing, but fluctuating, trend, especially in 1982 and in 1992 due to two volcano eruptions; the AOD values experienced a dramatically increasing period during 2000–2007 with the rapid economic development and “population explosions” in China/after 2008, the AOD values gradually decreased from 0.297 (2008) to 0.257 (2017). The AOD values in China were generally higher in spring than that in other seasons. The Sichuan Basin has always been an area with high AOD values owing to the strong human activity and the basin topography (hindering aerosol diffusions in the air). In contrast, the Qinghai Tibet Plateau has always been an area with low AOD values due to low aerosol emissions and clear sky conditions there. The trend analysis of AOD values during 1980–2017 in China indicated that the significant increasing trend was mainly observed in Southeastern China. By contrast, the AOD values in the northernmost of China showed a significant decreasing trend. Then, the contributions (AODP) of the AOD for black carbon aerosol (BCAOD), dust aerosol (DUAOD), organic carbon aerosol (OCAOD), sea salt aerosol (SSAOD), and SO4 aerosol (SO4AOD) to the total AOD values were calculated. The results showed that DUAOD (25.43%) and SO4AOD (49.51%) were found to be the main driving factors for the spatial and temporal variations of AOD values. Finally, the effects of anthropogenic aerosol emissions, socioeconomic factors, and land-use and land coverage changes on AOD were analyzed. The GDP, population density, and passenger traffic volume were found to be the main socioeconomic drivers for AOD distributions. Relatively larger AOD values were mainly found in urban land and land covered by water, while lower AOD values were found in grassland and permanent glacier areas.
3D-Gabor Inspired Multiview Active Learning for Spectral-Spatial Hyperspectral Image Classification
Authors: Hu Jie , He Zhi , Li Jun , He Lin , Wang Yiwen
Published: July 2018

Active learning (AL) has been shown to be very effective in hyperspectral image (HSI) classification. It significantly improves the performance by selecting a small quantity of the most informative training samples to reduce the complexity of classification. Multiview AL (MVAL) can make the comprehensive analysis of both object characterization and sampling selection in AL by using various features of multiple views. However, the original MVAL cannot effectively exploit the spectral-spatial information by respecting the three-dimensional (3D) nature of the HSI and the query selection strategy in the MVAL is only based on the disagreement of multiple views. In this paper, we propose a 3D-Gabor inspired MVAL method for spectral-spatial HSI classification, which consists of two main steps. First, in the view generation step, we adopt a 3D-Gabor filter to generate multiple cubes with limited bands and utilize the feature assessment strategies to select cubes for constructing views. Second, in the sampling selection step, a novel method is proposed by using both internal and external uncertainty estimation (IEUE) of views. Specifically, we use the distributions of posterior probability to learn the “internal uncertainty” of each independent view, and adopt the inconsistencies between views to estimate the “external uncertainty”. Classification accuracies of the proposed method for the four benchmark HSI datasets can be as high as 99.57%, 99.93%, 99.02%, 98.82%, respectively, demonstrating the improved performance as compared with other state-of-the-art methods.
Validation of Improved Significant Wave Heights from the Brown-Peaky (BP) Retracker along the East Coast of Australia
Authors: Peng Fukai , Deng Xiaoli
Published: July 2018

Improved significant wave heights (SWHs) along the east coast of Australia have been estimated using the parameters resolved by a Brown-peaky (BP) retracker through reprocessing of three years of Jason-1 altimetric waveforms. The BP-estimated SWHs are validated against eight waverider buoys along the coast, and compared with the SWHs estimated by the standard four-parameter maximum likelihood estimator (MLE4). When assessing 1 Hz coastal SWHs for distances from 12 km to the coast, mean standard deviations (STDs) of BP SWHs vary from ca. 0.5 m to 0.9 m, while those of MLE4 SWHs increase from ca. 0.6 m to ca. 2.3 m, indicating a dramatically drop in the quality of MLE4-derived SWHs at the coast. The BP retracker has retrieved ca. 80% of 1 Hz coastal SWHs, which are more than those (ca. 50%) by the standard MLE4. The validation of 1 Hz SWHs is performed by calculating the along-altimeter-track pointwise bias, STD and correlation coefficient between altimetry and buoys. The results show that within 30 km off the coast the BP dataset has better agreement with buoy’s wave heights than the SGDR MLE4 dataset in terms of the BP’s small absolute biases and STDs, as well as high correlation coefficients.
Feature Surface Extraction and Reconstruction from Industrial Components Using Multistep Segmentation and Optimization
Authors: Wang Yuan , Wang Jiajing , Chen Xiuwan , Chu Tianxing , Liu Maolin , Yang Ting
Published: July 2018

The structure of industrial components is diversified, and extensive efforts have been exerted to improve automation, accuracy, and completeness of feature surfaces extracted from such components. This paper presents a novel method called multistep segmentation and optimization for extracting feature surfaces from industrial components. The method analyzes the normal vector distribution matrix to segment feature points from a 3D point cloud. The point cloud is then divided into different patches by applying the region growing method on the basis of the distance constraint and according to the initial results. Subsequently, each patch is fitted with an implicit expression equation, and the proposed method is combined with the random sample consensus (RANSAC) algorithm and parameter fitting to extract and optimize the feature surface. The proposed method is experimentally validated on three industrial components. The threshold setting in the algorithm is discussed in terms of algorithm principles and model features. Comparisons with state-of-the-art methods indicate that the proposed method for feature surface extraction is feasible and capable of achieving favorable performance and facilitating automation of industrial components.
Targeting FRET-Based Reporters for cAMP and PKA Activity Using AKAP79
Authors: Musheshe Nshunge , Lobo Miguel J. , Schmidt Martina , Zaccolo Manuela
Published: July 2018

Fluorescence resonance energy transfer (FRET)-based sensors for 3′–5′cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) allow real-time imaging of cAMP levels and kinase activity in intact cells with high spatiotemporal resolution. The development of FRET-based sensors has made it possible to directly demonstrate that cAMP and PKA signals are compartmentalized. These sensors are currently widely used to dissect the organization and physiological function of local cAMP/PKA signaling events in a variety of cell systems. Fusion to targeting domains has been used to direct the sensors to a specific subcellular nanodomain and to monitor cAMP and PKA activity at specific subcellular sites. Here, we investigate the effects of using the A-kinase anchoring protein 79 (AKAP79) as a targeting domain for cAMP and PKA FRET-based reporters. As AKAP79 interacts with PKA itself, when used as a targeting domain, it can potentially impact on the amplitude and kinetics of the signals recorded locally. By using as the targeting domain wild type AKAP79 or a mutant that cannot interact with PKA, we establish that AKAP79 does not affect the amplitude and kinetics of cAMP changes or the level of PKA activity detected by the sensor.
The Accuracy of the Detection of Body Postures and Movements Using a Physical Activity Monitor in People after a Stroke
Authors: Fanchamps Malou H. J. , Horemans Herwin L. D. , Ribbers Gerard M. , Stam Henk J. , Bussmann Johannes B. J.
Published: July 2018

Background: In stroke rehabilitation not only are the levels of physical activity important, but body postures and movements performed during one’s daily-life are also important. This information is provided by a new one-sensor accelerometer that is commercially available, low-cost, and user-friendly. The present study examines the accuracy of this activity monitor (Activ8) in detecting several classes of body postures and movements in people after a stroke. Methods: Twenty-five people after a stroke participated in an activity protocol with either basic activities or daily-life activities performed in a laboratory and/or at home. Participants wore an Activ8 on their less-affected thigh. The primary outcome was the difference in registered time for the merged class “upright position” (standing/walking/running) between the Activ8 and the video recording (the reference method). Secondary analyses focused on classes other than “upright position”. Results: The Activ8 underestimated the merged class “upright position” by 3.8% (775 s). The secondary analyses showed an overestimation of “lying/sitting” (4.5% (569 s)) and of “cycling” (6.5% (206 s)). The differences were lowest for basic activities in the laboratory and highest for daily-life activities at home. Conclusions: The Activ8 is sufficiently accurate in detecting different classes of body postures and movements of people after a stroke during basic activities and daily-life activities in a laboratory and/or at home.
Sensitive Detection of Escherichia coli O157:H7 in Food Products by Impedimetric Immunosensors
Authors: Malvano Francesca , Pilloton Roberto , Albanese Donatella
Published: July 2018

In this work, the development of an impedimetric label-free immunosensor for the detection of Escherichia coli O157:H7 is reported. Different immobilization techniques of monoclonal anti-E. coli were tested, in order to reach the very low limit of detections. The comparison between the immobilization procedures underlined the advantages of the oriented procedure and the use of a dendrimer, which allowed for immobilizing a higher number of antibody units, reaching a very high sensitivity. However, the use of activated ferrocene as electron-transferring mediator, which improved the electrical properties of the system, resulted in a very low limit of detection equal to 3 cfu/mL. This immunosensor was used to analyze milk and meat samples obtaining a good agreement with the results of the ELISA methods.
Design of Sustainable Outsourcing Services for Facilities Management: Critical Success Factors
Authors: Lok Ka Leung , Opoku Alex , Baldry David
Published: July 2018

The management problems of Facilities Management (FM) outsourcing relationships occur because of provision of low quality analytical, managerial, cooperative, and professional services. On selection, the ideal service providers for specific FM outsourcing contractual procurement needs is of paramount importance to achieve high quality FM services. This paper aims at reviewing the concept of outsourcing in relation to facilities management and dealing with the importance of outsourcing success. Factors of outsourcing strategies from the perspectives of clients and service providers are examined and analysed through the Delphi technique in Hong Kong. The results reveal four main drivers of FM practice through evaluation of thirty-five outsourcing critical success factors identified by clients and service providers. Evaluation of the critical success factors from FM drivers shows that there is an inclination towards FM competence, measurement of performance, cost effectiveness, etc. from clients, whilst there is an inclination to the core skills, measurement of performance, allocation of human resources, cost effectiveness, customers’ satisfaction, etc. from service providers. The result of the study reveals an interesting understanding that the impact of outsourcing critical success factors can be strategically implemented into the outsourcing strategies in Hong Kong’s FM practice.
A Catalogue Supporting Software Sustainability Design
Authors: Oyedeji Shola , Seffah Ahmed , Penzenstadler Birgit
Published: July 2018

Like other communities, sustainability in and for software design is a grand research and development challenge. Current research focuses on eliciting the meanings of sustainability and on building approaches for its engineering and integration into the mainstream software development lifecycle. However, few concrete guidelines that software designers can apply effectively are available. A guideline aims to streamline the design processes according to a set of well-known research routines or sound industry practices. Such guidelines can help software developers in the elicitation of sustainability requirements and testing software against these requirements. This paper introduces a sustainability design catalogue (SSDC) comprising a series of guidelines. It aims to assist software developers and managers in eliciting sustainability requirements, and then in measuring and testing software sustainability. The catalogue is based on reviews of the current and past research on sustainability in software engineering, which are the grounds for the development of the catalogue. Four different case studies were analyzed using the Karlskrona manifesto principles on sustainability design. A pilot framework is also proposed that includes a set of sustainability goals, concepts and methods. It exemplifies how to apply and quantify sustainability.