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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Alignment of LC-MS Data Using Peptide Features

Tang, Xincheng 2011 December 1900 (has links)
Integrated liquid-chromatography mass-spectrometry(LC-MS) is becoming a widely used approach for quantifying the protein composition of complex samples.In the last few years,this technology has been used to compare complex biological samples across multiple conditions. One challenge in the analysis of an LC-MS experiment is the alignment of peptide features across samples. In this paper,we proposed a new method using the peptide internal information (both LC-MS and LC-MS/MS information) to align features from multiple LC-MS experiments.We defined Anchor points which are data elements that are highly confident we have identified and are shared by both samples. We chose one sample as template data set, find Anchor points in this sample, then apply alignment to modify another sample, find Anchors in modified sample, these Anchors should line up with one another. One advantage of our method is that it allows statistical assessment of alignment performance. Use anchor points to perform alignment between samples, and labeling an objective performance in LC-MS.
12

Entwicklung und Anwendung von flüssigchromatographischen Analyseverfahren zum Nachweis von Diarrhetic Shellfish Poisoning (DSP)-Toxinen

Rühl, Alexander. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--Jena.
13

Addysg Gymraeg ail iaith mewn Ysgolion cyfrwng-Saesneg : astudiaeth i archwilio i ba raddau y mae amodau dysgu'r rhaglen Gymraeg ail iaith yng Nghyfnodau Allweddol 2 a 3 yn gymwys i gynhyrchu siaradwyr yr iaith

Beard, Ashley Charlotte January 2016 (has links)
Diben yr astudiaeth hon oedd ymchwilio’r ddarpariaeth iaith Gymraeg mewn ysgolion cynradd ac uwchradd cyfrwng-Saesneg, Cyfnodau Allweddol 2 a 3 er mwyn dirnad i ba raddau y gall gynhyrchu siaradwyr Cymraeg. Agenda ieithyddol Llywodraeth Cymru ar gyfer creu Cymru ddwyieithog a ysgogodd y gwaith ymchwil hwn. Ymhellach, rhydd pwyslais y Cwricwlwm Cenedlaethol ar sgiliau llafaredd, ynghyd ag argymhelliad parhaus Estyn a Llywodraeth Cymru i ddatblygu sgiliau cyfathrebol y disgyblion gyd-destun i’r astudiaeth. Gosodwyd y gwaith ymchwil o fewn fframwaith cysyniadol yn seiliedig ar egwyddorion dysgu ac addysgu ail iaith y Cyrchddull Cyfathrebol cyfredol. Cyfraniad gwreiddiol y gwaith ymchwil hwn i’r maes dysgu ac addysgu Cymraeg ail iaith yw dangos bod y ddarpariaeth Gymraeg yn yr ysgolion a gyfranogodd yn pwyso’r glorian ar ochr dulliau addysgu ail iaith traddodiadol; dulliau sydd yn arwain at anghyseinedd ymarferol ac, o ganlyniad, wedi tanseilio ffydd yn eu cymhwysedd i ddatblygu siaradwyr. Arsylwyd mewnbwn ieithyddol a oedd wedi’i gyfyngu i eirfa a strwythurau iaith ynysedig ac a oedd, ar y cyfan, yn camgynrychioli natur yr iaith darged. Tueddai ymarferion llafar ddatblygu o ymarferion mecanyddol i gyfnewidiau trafodaethol gyda diffyg pwyslais ar ddefnydd iaith at ddibenion ystyrlon. Dadleuir nad oedd y mewnbwn ieithyddol, y deunyddiau dosbarth na’r gweithgareddau yn cyfrannu at ddatblygu hunaniaeth ddiwylliannol na sgiliau cyfathrebol y disgyblion. Cynigia’r gwaith ymchwil hwn fewnwelediad gwerthfawr i wersi Cymraeg drwy astudiaeth feintiol fanwl o nodweddion yr addysgeg a fabwysiedir i addysgu’r Gymraeg mewn ysgolion cyfrwng-Saesneg. Yn sgil adolygiad Dyfodol Llwyddiannus Donaldson (LlC, 2015a) o’r Cwricwlwm Cenedlaethol, ac er mwyn gwireddu gweledigaeth Llywodraeth Cymru o Gymru ddwyieithog, gall canlyniadau’r ymchwil hwn gyfrannu at sicrhau nad yw’r un addysgeg Gymraeg ail iaith yn parhau o dan gyfundrefn ‘ddiwygiedig’.
14

Building human capital for the tourism sector : a case study from Yemen

Al-Saqqaf, Raidan Abdulaziz January 2018 (has links)
This thesis examines how investing in tourism education was explored as an attractive national development policy in Yemen, where this education would provide the human capital needed for the sector to grow. This examination adopted a dual lens, namely the lens of policy makers responsible for the creation of this educational process as well as that of the students involved. The underlying thought for this research can be summed up in the simple notion: How successful is an educational institution in creating human capital for the tourism sector as seen by both the policymakers and the young people engaged? Responding to this question requires considering the intended goals of both policymakers and students, seen as to accelerate national development and individual wellbeing respectively. Investigating this question is important, particularly given Yemen’s developmental status as a Least Developed Country (LDC) experiencing recurrent cycles of instability, and based on the human capital premise that investing in education contributes positively to achieving development outcomes across the board. For this research, I used a purpose-built vocational training institute as a case study to understand more about how tourism education as an instrument to achieve development goals was understood, formulated, and executed. I relied on official documentation as well as primary data collected through interviews and focus group discussions to build the case study. Those interviewed included high-level officials and other experts as key informants, as well as students who were also engaged through in-depth focus group discussions. The collection of primary data from students enrolled in the institution was useful not only in understanding their perceptions towards the human capital development process through the institution, but also to learn more about issues that potentially contributed to the frustrations that were expressed in the Arab spring events of 2011. My research indicated that the conceptual framework used to guide policymaking in the case of NAHOTI was rather under informed and missed several important elements, thereby limiting the contributions of tourism education to development goals as intended. For example, an evaluation of evidence-based policy options was largely absent, and the process excluded taking into account the views and priorities of the young people despite their central role and contributions to the success of this process. This led to a range of complications that affected the viability of tourism education as a development instrument as evident in the case study. Furthermore, the research revealed another dynamics relating to expectations on returns to investment in education at both the public and private levels. For instance, the students’ expectations from the case study institution were based on their employability interests towards improving their economic prospects, and therefore they viewed the educational process in the institution largely as a means to an end in terms of improving their access to the labour market. This did not only affect their potential contributions to the tourism sector, but also added to their frustrations and disenfranchisement with governance processes at large. Finally, this research concludes with a number of findings and policy implications for the prospects of investing in human capital for development. It also proposes a range of recommendations to maximising the potential contributions of students in building human capital, through adopting a number of participatory and inclusive social dialogue measures within human capital development frameworks.
15

An exploration of the suitability of design education approaches in enabling enterprise and entrepreneurship educators to enhance undergraduate students' opportunity recognition attributes, behaviours and skills in Higher Education in Ireland

Tynan, Margaret January 2017 (has links)
Enterprise and entrepreneurship (EE) education aims to equip students with the attributes, behaviours and skills to recognise and respond to opportunities. However, evidence suggests that this does not happen in practice. Opportunity recognition (OR) is frequently cited as a competence from EE education, yet studies suggest it is rarely developed as such. This has resulted in calls for practical guidelines and frameworks on OR to be made available to EE educators. While OR is recognised as a creative process, there is a distinct lack of creativity driven approaches available to educators. Similarly, a growing awareness of the potential value of ‘design’ in EE has resulted in calls to consider education and assessment methodologies used in Design Education (DE) for the creative aspects of EE education. This study responds to those calls. The research explores the potential suitability of DE approaches to OR education (ORedu), within the context of Higher Education (HE) in Ireland. A qualitative approach was taken, involving both semi-structured interviews and observation of educators in practice. This research is the first of its kind to reveal the existence of an ORedu process, which was found to lack prominence in existing EE education. The current ORedu process was considered sub-optimal, with students rushing into the process or selecting unsuitable or convenient opportunities. DE was found to develop ‘designerly ways of thinking’ in students, facilitating the generation and development of new ideas, thereby making it relevant from an OR perspective. This was enabled by its delivery, the requirement for students to explore, continuous educator challenge and exposure to managed risk in safe learning environments. Key theoretical contributions include a refined ORedu process and an ORedu framework to enable the progressive development of student OR competence. Practical implications of this research include recommendations for EE educator training.
16

Stanovení vybraných pesticidů a jejich metabolitů technikou LC/MS / Determination of selected pesticides and their metabolites by LC/MS

Kořínková, Petra January 2011 (has links)
Pesticides are the substances designed for destroying, preventing and controlling of pests and protection of plants. Their wide usage in agriculture causes contamination of ground, surface and drinking water, because wastewater treatment plants are not able to remove them. Mostly used pesticides are triazine based pesticides. However their usage is worldwide reduced because of their negative influences on human health and contamination of environment especially with their metabolites, about their toxicity are no information. A method for determination of triazine pesticides atrazine, cyanazine, propazine, simazine, terbuthylazine and their metabolites hydroxytrazine, desethylatrazine, desisopropylatrazine, hydroxyterbuthylazine a desethylterbuthylazine was developed and validated in this diploma work. The determination was realized by LC-MS/MS with electrospray ionization. LOD ranged between 0.5-3.2 pg/ml and LOQ between 1.5-9.6 pg/ml. A test of stability of the maternal substances of these pesticides was performed, in which temperature was found to have the biggest influence on their degradation. A monitoring of the presence of triazine pesticides and their metabolites in water was carried out in Czech Republic. Low concentrations of the maternal substances in surface water and ground water were...
17

LC-HRMS analýza vybraných léčiv v biologickém materiálu I. / LC-HRMS analysis of selected drugs in biological material I.

Tomanová, Jana January 2020 (has links)
Charles Univesity, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Jana Tomanová Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Consultant: PharmDr. Vít Šesták, Ph.D. Title of the Diploma Thesis: LC-HRMS analysis of selected drugs in biological material I. High performance liquid chromatography is one of the most widespread separation analytical techniques. It is used in various medical, pharmaceutical and industrial laboratories. It uses different affinities of the substances in the analysed mixture to the mobile and stationary phases. Mass spectrometry is one of the instrumental techniques by which charged particles are separated in the gas phase based on the mass- to-charge ratio. Nowadays, great emphasis is placed on the fact that the individual analytical methods which are being developed are subsequently validated according to a guideline issued by national or international authorities. Validation is a process that verifies that a method is suitable for its intended use. In this thesis, the conditions for the determination of warfarin in patient's serum by means of mass spectrometer with LTQ XL linear ion trap were optimized and validated. The optimization of the method was based on the already developed and validated...
18

LC-HRMS analýza vybraných léčiv v biologickém materiálu II. / LC-HRMS analysis of selected drugs in biological material II.

Švarcová, Kristýna January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Kristýna Švarcová Consultant: RNDr. Martin Mžik, Ph.D. Supervisor: doc. PharmDr. Radim Kučera, Ph.D. Title: LC-HRMS analysis of selected drugs in biological material II. Anxiety disorders affect up to 25 % of the population in their life, the lifetime prevalence is 13,6 %. Insomnia affect at least one third of the population in their life, the prevalence is 15-40 %. Drugs used to treat anxiety and insomnia easily cross the blood-brain barrier and affect the CNS. It is therefore necessary to determine the correct dosing schedule and monitor treatment. The result is optimization of treatment, reduction of side effects and increased patient adherence to treatment. The rapid qualitative and quantitative analysis for urgent cases of intoxication is also needed. This diploma thesis deals with development and optimization of an extraction method for selected benzodiazepines (alprazolam, bromazepam, diazepam, chlordiazepoxide, clonazepam, midazolam, oxazepam) and zolpidem in human serum. Subsequently, the whole analytical method was validated for use in clinical practice using the UHPLC-HRMS. Protein precipitation with acetonitrile was the most suitable sample preparation...
19

A LOW-POWER AND LOW-JITTER ANALOG FREQUENCY SYNTHESIZER FOR 5G WIRELESS COMMUNICATION AND IoE/IoT APPLICATIONS

Bagheri, Mohammad January 2023 (has links)
In the early 1980s and 1990s, the first- and second-generation networks in wireless communication, called 1G and 2G, were introduced with only limited data connectivity in the world. The former could only transfer voices while the latter could transfer voices and messages. By the early 2000s, however, the 3G networks began working and let people have real access to the internet. The greater functionality enabled by 4G networks evolved from increased demand for higher data rates in the early 2010s. Nowadays, we are totally engaged in 4G world of LTE (Long Term Evolution) owing to the eruptive increase of mobile internet in smart phones or other mobile devices. The 5G networks are categorized into two branches according to their frequencies: (i) sub-6 GHz (700 MHz to 6 GHz) and (ii) near-millimeter wave (25 to 30 GHz). Commonly used applications are included in the sub-6 GHz, also called the Internet-of-Everything (IoE) and Internet-of-Things (IoT). To fulfill the date rate required for 5G applications, implementing complex systems is necessary. Consequently, new challenges are imposed to implement these systems such as noise performance and output power. At the heart of these systems lie frequency synthesizers. Frequency synthesizers are used to up or down convert the carrier signal in communication systems. Phase-locked loops (PLLs) are routinely utilized for frequency synthesis in Radio Frequency (RF)/mm-wave transceivers. The main challenges to design a PLL are phase noise (PN) or jitter, as well as power consumption. The main objective of this thesis is to carry out research on a fully integrated analog PLL fractional-N frequency synthesizer for 5G wireless communication and IoE/IoT applications in sub-6 GHz. To do this, we have studied the trends in the research of LC-VCOs (voltage-controlled oscillators) and identified the methods for going towards a low flicker-noise corner. Then, we have implemented the designed LC-VCO which is the main noise source in PLLs. In the final step we have designed the sub-blocks of the fractional-N analog frequency synthesis. The sub-blocks have been optimized to have less power dissipations. The implementation of a fully integrated analog PLL fractional-N frequency synthesizer is done in 180-nm standard CMOS technology (TSMC). It covers two frequency ranges including 2.4 to 2.48 GHz and 5 to 5.825 GHz. The phase noise at 10KHz varies between -94 dBc/Hz to -115dBc/Hz. / Thesis / Doctor of Philosophy (PhD) / The data rate in wireless, cellular communications, and wireline keeps growing by nearly 10 times per 5 years. To fulfill such date rate, implementing complex systems is necessary. Consequently, new challenges are imposed to implement these systems such as noise performance and output power. At the heart of these systems lie frequency synthesizers. Frequency synthesizers are used to up or down convert the carrier signal in communication systems. Phase-locked loops (PLLs) are routinely utilized for frequency synthesis in Radio Frequency (RF)/mm-wave transceivers. The main challenges to design a PLL are phase noise (PN) or jitter, as well as power consumption. This dissertation aims to implement an ultra-low power and low jitter frequency synthesizer for 5G wireless communication and IoE/IoT applications in 180-nm standard CMOS technology (TSMC). An analog PLL is used in this frequency synthesizer.
20

A Study of Some Factors Influencing Attitudes Towards Energy Education and its Relationship with Academic Qualifications and Personality Characteristics of Secondary School Teachers in Devi Patan Region (Uttar Pradesh) India

Shukla, Bhavna 05 1900 (has links)
This study concerns seven factors Area, Sex, Age, Stream, Social background, Economic Status and Academic Qualification influencing attitudes towards Energy Education and their relationship with personality characteristics. Objectives of this study were to compare the attitudes of these different groups which were translated into null hypotheses. Stratified random sampling was applied and data was collected from secondary school teachers of Devi Patan Region, Uttar Pradesh (India) using Likert Scale and Meenakshi Personality Inventory. It was found that 96% teachers cutting across above factors accepted the importance of Energy Education and their personality traits do not have any significant effect on attitudes.

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