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Development of small-angle scattering pair distribution function analysis techniques and application to nanoparticles assemblies
With the improvement in synthesis method, a variety of nanoparticles (NPs) with nearly uniform distribution in size and morphology are now available to scientists. This progress opens a new opportunity of assembling these high quality nanoparticles into metamaterial - nanoparticle assemblies (NPAs). The properties of NPA depend on the interactions between constituent NPs, therefore NPA offer a distinct advantage in designing material properties that are not available in the bulk phase (crystal) or discrete phase (nanoparticle). Novel application of NPA in modern devices, such as solar cells and field effect transistors, had also been demonstrated. The spatial arrangements of NPs is the key factor to their interactions, therefore, it is crucial to characterize the structure of NPA quantitatively. The technique of diffraction plays an unique role for characterizing NPA structure, as it not only offers the structural type, which may also be obtained from imagine technique, but also yields structural information in three-dimension, such inter-particle distance and the range of structural coherence of the packing order. Traditionally, the diffraction analysis is based on crystallography and is carried out in reciprocal space. However, it has been known local structure is overlooked in this kind of crystallographic analysis, which places a challenge for have a comprehensive understanding of the NPA structure.
The pair distribution function (PDF) analysis, which is powerful in probing local structures for atomic systems, serves as a promising tool for characterizing NPA structure. How- ever, the approach of using PDF analysis for NPA structure characterization has barely been explored. In this thesis, I will present the methodological developments of the PDF technique. Starting from presenting a machine-learning-assisted approach for predicting the space group of its structure from the PDF, I will be focusing on the aspect of accelerating the structure modeling steps with PDF. Next, the development of pair distribution function analysis in small-angle scattering domain sasPDF will be introduced, including software package PDFgetX3 which is aiming to facilitate the extraction of PDF from small-angle scattering data quickly. The approach of sasPDF is validated against three representative structures across different levels of structural order. Finally, the example of applying sasPDF method to identify the jamming transition signature in polymer-ligated NPA is introduced, followed by another example of discovering multiply-twinned structure from the reprogramming of DNA-ligated NPA
Linkage analysis identifies an ubiquitin transferase gene as a novel marker for reduced quinine and quinidine responsiveness in Plasmodium falciparum
Die Entstehung und die Ausbreitung von Medikamentenresistenzen hat die Behandlung von Malaria, einer Infektionskrankheit, welche mehr als eine Millionen Tote in Afrika verursacht, erschwert. Chloroquin war ab dem Zweiten Weltkrieg das wichtigste Medikament bei der Behandlung von Malaria. Allerdings trat in den späten 50iger Jahren Chloroquinresistenz in Südostasien auf, welche sich dann schnell nach Südamerika und Afrika ausbreitete. Deshalb wurde Chloroquin bald darauf abgesetzt. Chloroquinresistenz wird hauptsächlich durch eine Punktmutation von Aminosäure K zu T an Position 76 in dem chloroquine resistance transporter, pfcrt, verursacht. Pfcrt-Mutationen beeinflussen auch Resistenzen gegen andere Quinolinmedikamente wie zum Beispiel Chinin. Im Falle von Chinin gibt es Resultate, welche darauf hindeuten, dass Chininresistenz von mehr Faktoren beeinflusst wird als pfcrt. Durch Analyse der Chininakkumulation von den Nachkommen der genetischen Kreuzung zwischen HB3 und Dd2 in vorherigen Studien konnte ein neuer sogenannter “quantitative trait” Lokus auf Chromosom 7 identifiziert werden, B5M12. Der B5M12-Lokus interagiert synergistisch mit pfcrt bei der Reduzierung der Chininsuszeptibilität. Durch eine nachfolgende Analyse von 50 Feldisolaten und Laborstämmen konnten wir den Lokus auf zwei Kandiadatengene eingrenzen: die Ubiquitintransferase und RAMA (Rhoptry Associated Membrane Antigen). Eine Y zu F Mutation an Position 1388 in der Ubiquitintransferase interagiert synergistisch mit mutiertem pfcrt bei Chininresistenz. Zusätzlich wurde unter Quininselektionsdruck durch Kopplungsanalyse die Ubiquitintransferase Y1388F mit pfcrt K76T co-selektiert. Im Anschluss daran wurde RAMA als Kandidatengen ausgeschlossen, aufgrund eines fehlenden Synergismus zu mutiertem pfcrt und des Trends der Zusammenlagerung mit pfcrt. Die Identifizierung einer möglichen Ubiquitintransferase könnte die molekulare Kontrolle der Quininresistenz im Feld verbessern. Zusätzlich haben wir die Polymorphismen von pfcrt und pfmdr1 in 50 Feldisolaten und Laborstämmen untersucht. Wir konnten einen zusätzlichen Effekt der geospezifischen pfcrt M75E Mutation auf eine verringerte Quininsuszeptibilität zeigen. Im Fall von pfmdr1 konnte für keine der Mutationen ein Einfluss auf die Quininsuszeptibilität gezeigt werde
An Arena Simulation Model For Empty Container Reposition Problems
The imbalance in international trading has deeply affected shipping lines’ income. Due to this shipping lines have started to focus on container reposition problems to enhance their competitive strength. However, according to research report from Crinks (2000), the author points out that in global container utilization, a large percentage is used for idle and empty container repositioning. In addition, container reposition operations rely on operators’ experiences and historical data. It is clear that shipping lines bear large uncertain risks in the process. Many researchers believe that container reposition problems involve many factors, thus, constructing an operation model which can support operators is an essential process.
This dissertation is utilizing the concept of simulation modelling based on the idea of total container number balancing to cope with container reposition problems. The simulation model in this dissertation contains port operation programme and inland transport programme to simulate practical operating systems of container reposition operations. Additionally, this simulation model is built on Arena simulation software which allows researchers utilizing an intuitive method to construct container reposition simulation model.
In the introduction of variability, as mentioned before, this dissertation is utilizing the concept of total container number balancing to address container reposition problems. The total container number is the number of containers which are under shipping lines control. Thus, this dissertation modifies some variations like changing unloading and loading time in port operation programme. The results show that different degree of changing in these variations will affect total container numbers in each port controlled by shipping lines
An Arena Simulation Model For Empty Container Reposition Problems
The imbalance in international trading has deeply affected shipping lines’ income. Due to this shipping lines have started to focus on container reposition problems to enhance their competitive strength. However, according to research report from Crinks (2000), the author points out that in global container utilization, a large percentage is used for idle and empty container repositioning. In addition, container reposition operations rely on operators’ experiences and historical data. It is clear that shipping lines bear large uncertain risks in the process. Many researchers believe that container reposition problems involve many factors, thus, constructing an operation model which can support operators is an essential process.
This dissertation is utilizing the concept of simulation modelling based on the idea of total container number balancing to cope with container reposition problems. The simulation model in this dissertation contains port operation programme and inland transport programme to simulate practical operating systems of container reposition operations. Additionally, this simulation model is built on Arena simulation software which allows researchers utilizing an intuitive method to construct container reposition simulation model.
In the introduction of variability, as mentioned before, this dissertation is utilizing the concept of total container number balancing to address container reposition problems. The total container number is the number of containers which are under shipping lines control. Thus, this dissertation modifies some variations like changing unloading and loading time in port operation programme. The results show that different degree of changing in these variations will affect total container numbers in each port controlled by shipping lines
Major interventions are associated with survival of out of hospital cardiac arrest patients - a population based survey
Background. The overall survival rate of
out-of-hospital cardiac arrest (OHCA)
in Taiwan or even in the whole of Asia
is relatively low. Major interventions,
such as target temperature management
(TTM), coronary artery angiography, and
extracorporeal membrane oxygenation
(ECMO), have been associated with better
patient outcome. However, studies in Taiwan
revealing evidence of the benefits of
these interventions are limited.
Methods. A population-based study used
an 8-year database to analyze overall survival
and risk factors Ëťamong OHCA patients.
All adult non-trauma OHCA patients
were identified through diagnostic
and procedure codes. Hospital survival
and return of spontaneous circulation
(ROSC) were primary and secondary outcomes.
Logistic regression and Cox regression
analyses were conducted.
Results. There was a relationship between
major interventions (including TTM,
coronary artery angiography, and ECMO)
and better hospital survival. Age, income,
major interventions, and acute myocardial
infarction history were associated with
hospital survival. The adjusted hazard
ratios (HRs) were 0.406 (95% CI, 0.295
to 0.558), 1.109 (95% CI, 1.027 to 1.197),
1.075 (95% CI, 1.002 to 1.154), 1.097 (95%
CI, 1.02 to 1.181) and 0.799(95% CI, 0.677
to 0.942) for patients with major interventions,
age≥50, medium low and low income,
middle income, and acute myocardial
infarction history, respectively.
Conclusion. This population-based study
in Taiwan revealed that older age (≥50),
medium low and low income were associated
with a lower rate of survival. Major
interventions, including TTM, coronary
angiography, and ECMO, were related to
better survival
Cluster-mining: An approach for determining core structures of metallic nanoparticles from atomic pair distribution function data
We present a novel approach for finding and evaluating structural models of
small metallic nanoparticles. Rather than fitting a single model with many
degrees of freedom, the approach algorithmically builds libraries of
nanoparticle clusters from multiple structural motifs, and individually fits
them to experimental PDFs. Each cluster-fit is highly constrained. The
approach, called cluster-mining, returns all candidate structure models that
are consistent with the data as measured by a goodness of fit. It is highly
automated, easy to use, and yields models that are more physically realistic
and result in better agreement to the data than models based on cubic
close-packed crystallographic cores, often reported in the literature for
metallic nanoparticles
Glass-Embedded Fan-Out Antenna-in-Packaging for 5G Millimeter Wave Applications
The paper proposes a novel Antenna-in-Packaging (AiP) structure design for 60 GHz, millimeter wave WiFi applications. In the AiP design, single- or double-sided glass redistribution layers were embedded in a typical fan-out (FO) packaging structure to introduce design flexibility and to improve the radiation properties of the antenna. ANSYS-HFSS software was employed for electromagnetic (EM) characteristic simulations on the fan-out AiP (FO_AiP) design. To improve antenna radiation performance, single factor analyses were first performed to study the impact of each of the design parameters. A consecutive procedure followed to find more suitable combinations of the design parameters. As a result, two typical glass-embedded FO_AiP structures - one with 7.6 GHz bandwidth plus 4.7 dB gain and upward radiation, and another with 5.3 GHz bandwidth plus 5.2 dB gain and downward radiation, are proposed for the 60 GHz applications
Glass-Embedded Fan-Out Antenna-in-Packaging for 5G Millimeter Wave Applications
The paper proposes a novel Antenna-in-Packaging (AiP) structure design for 60 GHz, millimeter wave WiFi applications. In the AiP design, single- or double-sided glass redistribution layers were embedded in a typical fan-out (FO) packaging structure to introduce design flexibility and to improve the radiation properties of the antenna. ANSYS-HFSS software was employed for electromagnetic (EM) characteristic simulations on the fan-out AiP (FO_AiP) design. To improve antenna radiation performance, single factor analyses were first performed to study the impact of each of the design parameters. A consecutive procedure followed to find more suitable combinations of the design parameters. As a result, two typical glass-embedded FO_AiP structures - one with 7.6 GHz bandwidth plus 4.7 dB gain and upward radiation, and another with 5.3 GHz bandwidth plus 5.2 dB gain and downward radiation, are proposed for the 60 GHz applications
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