Dynamic of Publication Network in German Photovoltaic Industry

Besides high policy-induced motivations for development of research activities in photovoltaic industry, there have been a few social network studies concentrating on the scientific publication in this field. This study tried to shed light on the structure and evolution of publication network in German PV industry from 1988 to 2013. For this purpose, using the centrality indices, I realized the most influential actors as potential source of knowledge and actors who play the central role in knowledge production and diffusion. In next step, I investigated the dynamic of co-authorship network of scientists. Results showed that against the downward trend of network’s cohesion, overall compared to the same size random generated network, German PV co-authorship network is characterized as a small world network which emphasizes the efficient diffusion of knowledge compare to other type of network. Finally, to disclose the drivers behind the evolution of co-authorship network, I hypothesized two different scenarios. First, using descriptive analysis, the existence of preferential attachment mechanism is investigated. Fitting power law distribution over degree of nodes rejected our hypothesis for all investigating time windows. Therefore, preferential attachment mechanism cannot significantly explain the evolution of the network and reveals that network is robust in response to removal of large nodes. Second, looking at the composition of knowledge on map of science provided strong evidence in support of interdisciplinarity nature of German PV industry. Our descriptive analysis shows that along with existence of leading macro-disciplines such as Materials Science and Physics Applied, new subject categories of science have found a significant position over the existing knowledge domain during the observed period

The therapeutic effects of chamomilla tincture mouthwash on oral aphthae: a randomized clinical trial

Introduction: Recurrent aphthous stomatitis (RAS) is a common clinical condition producing painful ulcerations in the oral cavity. However, there has been no optimal therapeutic approach. Topical and systemic steroids commonly prescribed for the condition have local and systemic side-effects. Recently, there is growing tendency toward herbal medication in the modern society. The objective of this study was to assess the efficacy of a chamomilla mouth rinse on reducing the signs and symptoms of aphthous lesions in comparison with a placebo mouth rinse. Material and Methods: A randomized, triple-blind, placebo-controlled trial was performed on 36 patients, from cases diagnosed with RAS, attending the Department of Oral Medicine, Mashhad University of Medical Sciences. They were randomly divided into two groups: the intervention group(A), receiving chamomilla mouth rinse, and the control group (B) receiving a placebo rinse. The ability of the solution to control the pain and burning sensation and the number and size of the ulcers were evaluated. Results: The number of ulcers in the 3 rd visit (four days after treatment) showed a significant difference between the groups ( P <0.001). The pain and burning sensation (VAS) was reduced significantly in the test group in the 2 nd ( p =0.001),3 rd and 4 th visit ( P <0.001). Conclusions: Chamomilla mouth rinse was effective in the treatment of RAS, controlling the pain and burning sensation without producing any adverse side effects and can be advised as an alternative RAS treatment

Dynamic of Publication Network in German Photovoltaic Industry

Besides high policy-induced motivations for development of research activities in photovoltaic industry, there have been a few social network studies concentrating on the scientific publication in this field. This study tried to shed light on the structure and evolution of publication network in German PV industry from 1988 to 2013. For this purpose, using the centrality indices, We realized the most influential actors as potential source of knowledge and actors who play the central role in knowledge production and diffusion. In next step, we investigated the dynamic of co-authorship network of scientists. Results showed that against the downward trend of network’s cohesion, overall compared to the same size random generated network, German PV co-authorship network is characterized as a small world network which emphasizes the efficient diffusion of knowledge compare to other type of network. Finally, to disclose the drivers behind the evolution of co-authorship network, we hypothesized two different scenarios. First, using descriptive analysis, the existence of preferential attachment mechanism is investigated. Fitting power law distribution over degree of nodes rejected our hypothesis for all investigating time windows. Therefore, preferential attachment mechanism cannot significantly explain the evolution of the network and reveals that network is robust in response to removal of large nodes. Second, looking at the composition of knowledge on map of science provided strong evidence in support of interdisciplinarity nature of German PV industry. Our descriptive analysis shows that along with existence of leading macro-disciplines such as Materials Science and Physics Applied, new subject categories of science have found a significant position over the existing knowledge domain during the observed period

Dynamics of innovation and efficiency in banking system: An application of SFA and meta-frontier method

Abstract One of the most important problems in innovation arguments is how to identify and measure innovation. In industry sector, the available measurements to identify innovation activities are number of patents, R&D expenditure and share of R&D workers. Unfortunately these measurements for service sector especially financial sector are problematic and not readily available. This paper, following Bos et al. (2009), proposes changes of Technology Gap Ratio (TGR) as innovation activity in banking system and investigates it for the US commercial banks in years 2000-2013. For this purpose, at first step, the annual cost frontier functions (as representative of technology set for each year) are estimated by applying Stochastic Frontier Analysis (SFA). Consequently, the efficiency scores for each year are calculated for banks which operate under the same frontier functions. Then, the meta-frontier analysis is employed to estimate the potentially available cost function for the whole period. In next step, the TGR which indicates the relative distance of annual cost frontier function to the most efficient cost function (meta-frontier cost function) for the whole period is calculated. Finally, changes of TGR as a proxy of financial innovation during the time are illustrated by proper Salter curves. Results show that the average of TGR for the period 2000 to 2011 was associated with 2.88% annual growth rate. In other words, commercial banks in this period demonstrated an increasing level of innovation in their activities including financial products and services. In contrast, the results show that in last two years (2012 and 2013) this ratio had a considerable reduction, even less than the initial year. Thus, it seems that they have been less involved in innovation activities during the recent years

Dynamic of Publication Network in German Photovoltaic Industry

Besides high policy-induced motivations for development of research activities in photovoltaic industry, there have been a few social network studies concentrating on the scientific publication in this field. This study tried to shed light on the structure and evolution of publication network in German PV industry from 1988 to 2013. For this purpose, using the centrality indices, We realized the most influential actors as potential source of knowledge and actors who play the central role in knowledge production and diffusion. In next step, we investigated the dynamic of co-authorship network of scientists. Results showed that against the downward trend of network’s cohesion, overall compared to the same size random generated network, German PV co-authorship network is characterized as a small world network which emphasizes the efficient diffusion of knowledge compare to other type of network. Finally, to disclose the drivers behind the evolution of co-authorship network, we hypothesized two different scenarios. First, using descriptive analysis, the existence of preferential attachment mechanism is investigated. Fitting power law distribution over degree of nodes rejected our hypothesis for all investigating time windows. Therefore, preferential attachment mechanism cannot significantly explain the evolution of the network and reveals that network is robust in response to removal of large nodes. Second, looking at the composition of knowledge on map of science provided strong evidence in support of interdisciplinarity nature of German PV industry. Our descriptive analysis shows that along with existence of leading macro-disciplines such as Materials Science and Physics Applied, new subject categories of science have found a significant position over the existing knowledge domain during the observed period

Dynamics of innovation and efficiency in banking system: An application of SFA and meta-frontier method

Abstract One of the most important problems in innovation arguments is how to identify and measure innovation. In industry sector, the available measurements to identify innovation activities are number of patents, R&D expenditure and share of R&D workers. Unfortunately these measurements for service sector especially financial sector are problematic and not readily available. This paper, following Bos et al. (2009), proposes changes of Technology Gap Ratio (TGR) as innovation activity in banking system and investigates it for the US commercial banks in years 2000-2013. For this purpose, at first step, the annual cost frontier functions (as representative of technology set for each year) are estimated by applying Stochastic Frontier Analysis (SFA). Consequently, the efficiency scores for each year are calculated for banks which operate under the same frontier functions. Then, the meta-frontier analysis is employed to estimate the potentially available cost function for the whole period. In next step, the TGR which indicates the relative distance of annual cost frontier function to the most efficient cost function (meta-frontier cost function) for the whole period is calculated. Finally, changes of TGR as a proxy of financial innovation during the time are illustrated by proper Salter curves. Results show that the average of TGR for the period 2000 to 2011 was associated with 2.88% annual growth rate. In other words, commercial banks in this period demonstrated an increasing level of innovation in their activities including financial products and services. In contrast, the results show that in last two years (2012 and 2013) this ratio had a considerable reduction, even less than the initial year. Thus, it seems that they have been less involved in innovation activities during the recent years

Subject-Specific Calculation of Left Atrial Appendage Blood-Borne Particle Residence Time Distribution in Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia that leads to thrombus formation, mostly in the left atrial appendage (LAA). The current standard of stratifying stroke risk, based on the CHA2DS2-VASc score, does not consider LAA morphology, and the clinically accepted LAA morphology-based classification is highly subjective. The aim of this study was to determine whether LAA blood-borne particle residence time distribution and the proposed quantitative index of LAA 3D geometry can add independent information to the CHA2DS2-VASc score. Data were collected from 16 AF subjects. Subject-specific measurements included left atrial (LA) and LAA 3D geometry obtained by cardiac computed tomography, cardiac output, and heart rate.We quantified 3D LAA appearance in terms of a novel LAA appearance complexity index (LAA-ACI). We employed computational fluid dynamics analysis and a systems-based approach to quantify residence time distribution and associated calculated variable (LAA mean residence time, tm) in each subject. The LAA-ACI captured the subject-specific LAA 3D geometry in terms of a single number. LAA tm varied significantly within a given LAA morphology as defined by the current subjectivemethod and it was not simply a reflection of LAA geometry/appearance. In addition, LAA-ACI and LAA tm varied significantly for a given CHA2DS2-VASc score, indicating that these two indices of stasis are not simply a reflection of the subjects’ clinical status. We conclude that LAA-ACI and LAA tm add independent information to the CHA2DS2-VASc score about stasis risk and thereby can potentially enhance its ability to stratify stroke risk in AF patients

Rhodococcus equi által okozott nagyízületi endoprotézis körül kialakult fertőzés

Rhodococcus equi is a rare pathogen in humans causing infections mostly in immunocompromised hosts. We present the first case of periprosthetic joint infection caused by Rhodococcus equi. An 88-year-old male patient was referred to our clinic with a history of fever and right hip pain. The patient had multiple hip surgeries including total joint arthroplasty and revision for aseptic loosening on the right side. He was immunocompetent, but his additional medical history was remarkable for diabetes mellitus, diabetic nephropathy and stroke with hemiplegia resulting in immobilization. Radiography showed stable components, joint aspirate yielded Rhodococcus equi. Irrigation and debridement was proposed, but the patient refused any surgical intervention. Therefore antibiotic therapy was administered. At the last follow-up the patient is free of complaints but the C-reactive protein level is still elevated. This case illustrates the possible role of Rhodococcus equi in medical device-associated infections. Orv Hetil. 2017; 158(27): 1071-1074

Hemodynamic Indices and Shape-Based Models of Left Atrial Appendage to Enhance Stroke Prediction in Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia that leads to thrombus formation, mostly in the left atrial appendage (LAA). The current standard of stratifying stroke risk, based on the CHA2DS2-VASc score, does not consider LAA morphology/hemodynamics. The aim of this study was to determine whether LAA morphology and hemodynamics-based indices can stratify stroke risk independent of CHA2DS2-VASc score, left atrium size, and AF type. In a retrospective matched case-control study, patient-specific measurements in 128 AF patients included left atrial (LA) and LAA 3D geometry obtained by cardiac computed tomography, heart rate, cardiac output, and hematocrit. We quantified patient-specific 3D LAA morphology in terms of a novel LAA appearance complexity index (LAA-ACI) and employed computational fluid dynamics (CFD) analysis to quantify LAA mean residence time, tm and asymptotic concentration, C∞ of blood-borne particles. Effects of confounding variables were examined to optimize the CFD analysis. cardiac output, but not by the temporal pattern of pulmonary vein inlet flow, significantly affected LAA tm. Both the hematocrit level and the blood rheology model (Newtonian vs. non-Newtonian) also significantly affected LAA tm. Finally, 10,000 s was found to be a sufficient length of CFD simulation to calculate LAA tm in a consistent and reliable manner. LAA tm varied significantly within a given LAA morphology as defined by the current subjective method, and it was not simply a reflection of LAA geometry/appearance. In addition, LAA-ACI and tm varied significantly for a given CHA2DS2-VASc score, indicating that these two indices of stasis are not simply a reflection of the subjects’ clinical status. Using multiple logistic regression, we observed that ACI, tm, and C∞ had a modest, but statistically insignificant performance in predicting stroke (area under the ROC curve = 0.56–0.61). The temporal dissociation between adverse changes in LAA shape and hemodynamics-based indices and the actual stroke event can contribute to the negative result; a longitudinal study is necessary to address this issue. In addition, it is possible that a multiscale model that combines CFD-based hemodynamics simulation and biology-based thrombus formation can yield indices that can better stratify stroke risk in AF patients