DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires

PhD ThesisConductive polymers nanowires have been prepared using DNA-templating methods from monomer units designed in modular form. The monomer units comprise a polymerisable, pyrrolyl group, and a flexible alkyl linker attached to bipyridine groups in order to provide a metal-binding functionality within the polymers. The possibility for these DNA/polymer nanowires to act as templates for deposition of metal with enhanced electrical conductivity was also explored. Pyrrole with a flexible alkyl linker was combined with; pyridine (mono-I) as a control experiment, 2,2` bipyridyl (mono-II) and 4,4` bipyridyl (mono-III) with a metal ion binding site (nitrogen atom). This was in order to provide the metal-binding functionality for metal deposition to improve the conductivity as well as the morphology of the aimed hybrid templated nanowires. This series of pyrrole-pyridine derivatives were characterised using a range of techniques such as Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Mass Spectroscopy (MS) and Elemental Analysis. Prior to the nanowires fabrication, pyrrole, as a control, and the prepared monomer units (mono-I, mono-II and mono-III) were chemically polymerised in a bulk scale using FeCl3 as an oxidant, then spectroscopic data and electrical conductivity of the resulting polymers were measured. A significant decrease in conductivity of poly-I, poly-II and poly-III compared to PPy, but was especially observed for the bipyridinium derivatives. This was suggested to be due to the steric hindrance of the alkyl side chain in the polymer backbone, in addition, the involvement of the non-quaternised pyridyl nitrogen in poly-II and poly-III by the nucleophilic attack on pyrrolyl groups in the polymerisation reaction. DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires were synthesised at room temperature using the chemical oxidation method. The resulting CPs/DNA hybrids have been characterised using electronic and vibrational spectroscopic methods especially Ultraviolet-Visible (UV-Vis) spectroscopy and FTIR spectroscpy. The nanowires morphology was characterised using Atomic Force Microscopy (AFM). The electrical properties of the prepared nanowires were characterised using Electrostatic Force Microscopy (EFM), and measured using conductive AFM (c-AFM) and two iii terminal I/V technique, where the temperature dependence of the conductivity was probed. The conductivities of the prepared CPs/DNA nanowires are generally lower than PPy/DNA nanowires showing the large effect on N-alkylation in decreasing the conductivity of the polymer, but these are higher than the conductivity of their corresponding bulk films. This enhancement in conductivity could be attributed to the ordering of the polymer chains on DNA during the templating process. Finally, the prepared CPs/DNA nanowires were used as templates for the growth of copper nanowires at room temperature using aqueous solution of Cu(NO3)2 as a source of Cu2+ and ascorbic acid as reducing agent. AFM images showed that these nanowires were uniform and continuous compared to copper nanowires prepared using the templating method directly onto DNA. Electrical characterization of the nanowires by c-AFM revealed slight improvement in conductivity of these nanowires (Cu-CPs/DNA) compared to CPs/DNA nanowires before metallisation. Using similar preparation method, Poly-II/DNA nanostructures were also used as templates to direct the formation of Pd nanowires. An aqueous solution of PdCl2 was used as a source of Pd2+ ions and NaBH4 solution was used as reducing agent. AFM studies show that the resulting Pd-poly-II/DNA nanowires exhibit continuous and smooth morphology. Electrostatic Force Microscopy showed that these nanowires are electrically conductive.Libyan governmen

Kontrollierte klinische Studie über die Auswirkungen einer Pyloroplastik auf Krankheitsverlauf und Heilungsrate bei Kühen mit Labmagen-Blättermagendrehung

In einer kontrollierten klinischen Studie an Kühen mit Labmagen- und Blättermagendrehung wurde geprüft, ob der Heilungsverlauf durch eine Pyloroplastik nach Heinecke-Mikulicz günstig beeinflusst werden kann. Material und Methodik In diese Studie einbezogen wurden 60 Kühe der Rasse Deutsche Holsteins (48 schwarzbunte, 12 rotbunte) im Alter von 2,3 bis 8 Jahren (x = 4,6 Jahre). Einschlusskriterium war eine intraoperativ bestätigte Verlagerung des Labmagens nach rechts mit Drehung, unter Einbeziehung des Blättermagens, jeweils um mindestens 180°. Ausschlusskriterien waren Festliegen und / oder eine generalisierte Peritonitis. Nach Aufnahme in die Studie wurde der jeweilige Patient auf die Versuchsgruppe (Pyloroplastik nach Heinecke-Mikulicz; 30 Tiere) oder auf die Kontrollgruppe (keine Pyloroplastik; 30 Tiere) randomisiert. Abgesehen von der Pyloroplastik erhielten beide Gruppen die selbe Behandlung: Laparotomie von rechts, Reposition von Labmagen und Blättermagen sowie Omentopexie nach Dirksen. Während der Operation wurden 100 ml MastipentÒ, Fa. Merial (500 mg Ampicillin und 500 ml Cloxacillin / ml) in die Bachhöhle instilliert. Zusätzlich erhielten die Patienten 5 Tage lang jeweils 30.000 I.E. Procain-Penicillin / kg KM subkutan. Am Einlieferungstag wurden des weiteren 20 Liter einer 0,9 %igen Kochsalzlösung als i.v. -Dauertropfinfusion sowie 40 ml VitaSelenÒ, Fa. Selectavet (entspr. 6 g a-Tocopherolacetat und 66,8 mg Natriumselenit) s. c. und 20 ml FinadyneÒ i.v, Fa. Essex (entspr. 1,66 g Flunixin Meglumin) i.v. verabreicht. Die ersten 7 Tage nach der Operation standen die Patienten unter stationärer Beobachtung. Für die Beurteilung des Behandlungserfolges wurden täglich folgende Kriterien erfasst: Kotmenge, Pansenfüllung und Umfang des Abdomens. Zusätzlich wurden 24 Stunden, 48 Stunden und 7 Tage p. op. die Chlorid- und NEFA-Konzentration im Serum und die venösen Blutgaswerte (pH-Wert, Bikarbonatgehalt, Base Excess) bestimmt. Darüber hinaus wurde der Chloridgehalt im Pansensaft präoperativ und am 7. Tag p. op. gemessen. Drei Monate nach Entlassung der Patienten aus der Klinik wurden die Besitzer telefonisch über die weitere Entwicklung und den Verbleib der Probanden befragt. Die statistische Auswertung erfolgte mittels des Chi-Quadrat- und des Wilcoxon-Tests sowie der zweifaktoriellen Varianzanalyse (ANOVA) mit Messwiederholung bezüglich der Faktoren Gruppe und Messzeitpunkt. Ergebnisse Heilungsraten: Alle 30 Kühe der Kontrollgruppe sowie 28 der 30 Patienten aus der Versuchsgruppe konnten in die Auswertung einbezogen werden. Bei einem Tier der Versuchsgruppe war es nicht möglich, eine Pyloroplastik anzulegen, das andere Tier musste wegen eines Traumas euthanasiert werden. Aus der Versuchsgruppe konnten 22 Tiere (davon 17 Tiere als klinisch geheilt, 5 weitere als gebessert) zur weiteren Beobachtung in den Herkunftsbetrieb entlassen werden. In der Kontrollgruppe wurden 25 Tiere entlassen (21 als klinisch geheilt, 4 als gebessert). Der Unterschied zwischen beiden Gruppen ist nicht signifikant. Drei Monate nach Entlassung befanden sich noch 15 Tiere aus der Versuchsgruppe (53,6 %) und 17 Tiere aus der Kontrollgruppe (56,7 %) im Bestand und wurden normal genutzt. Von den 7 bzw. 8 Abgängen nach Entlassung aus der Klinik waren in der Versuchsgruppe 2 und in der Kontrollgruppe 3 nach Angaben der Besitzer auf andere Ursachen zurückführen (Fertilitätsstörung, Mastitis, Klauenprobleme). Bei allen noch während des Klinikaufenthaltes verendeten oder euthanasierten Tiere (Versuchsgruppe 6 Kühe, Kontrollgruppe 5 Kühe) fanden sich bei der Sektion hochgradige Labmagenveränderungen (Ulzera, Wandnekrosen). Entwicklung der klinischen und klinisch-chemischen Befunde: Weder hinsichtlich der Entwicklung der klinischen Befunde noch hinsichtlich der ausgewerteten Laborparameter ergaben sich zwischen beiden Gruppen signifikante Unterschiede. Schlussfolgerung Offensichtlich lassen sich die bei einem Teil der Kühe als Folge eines Labmagenvolvulus auftretenden Passagestörungen durch Erweiterung des Labmagenausgangs mittels Pyloroplastik nach Heinecke-Mikulicz nicht reduzieren. Somit kann diese relativ aufwendige Operation derzeit nicht als routinemäßige Maßnahme zur Prophylaxe solcher Komplikationen empfohlen werdenIn this clinically controlled study the influence of a pyloroplasty by Heinecke-Mikulicz on the recovery of cows suffering from abomasal and omasal volvulus was assessed. Material and methods 48 Frisian Holstein and 12 Red Holstein cows aged 2.3 to 8 years (mean 4.6) suffering from an at least 180 degree torsion of the abomasum and omasum to the right were included in this study. The diagnosis was confirmed intraoperatively. Patients suffering from the downer cow syndrome and/or generalized peritonitis were excluded. The animals were randomly allocated to either the study group (treatment with pyloroplasty by Heinecke-Mikulicz, 30 cows) or the control group (treatment without pyloroplasty, 30 cows). Apart from the pyloroplasty, all patients received the same treatment consisting of a right flank laparotomy with repositioning of the abomasum and omasum with omentopexy (method by Dirksen) and administration of 100 ml of Mastipent (Merial, 500 mg ampicillin and 500 ml cloxacillin/ml) intra-abdominally. In addition, 30,000 IU procaine-penicillin/kg body weight was administered subcutaneously (s.c.) for five days post surgery. Prior to the procedure 20 litres of 0.9% sodium chloride (NaCl) as a continuous intravenous (i.v.) infusion, 20 ml Finadyne i.v. (Essex, 1.66 g flunixin meglumin) and 40 ml of VitaSelen s.c. (Selectavet, 6 g alpha-tocopherole acetate, 66.8 mg sodium selenite) were administered. After the operation, the cows remained under clinical surveillance for 7 days. In order to assess the success of treatment, the amount of faeces passed, the filling of the rumen and the degree of abdominal distension were determined on a daily basis. In addition blood samples were drawn after 24 and 48 hours as well as on the 7th day post surgery to measure the serum levels of chloride, NEFA (non esterefied fatty acids) and the venous blood gas values (pH value, bicarbonate content and base excess). In addition, the chloride level in the rumen was determined prior to the operation and on the 7th day post surgery. Three months after discharge, the owners were questioned by telephone follow up regarding the clinical progression of the patients and the outcome. Statistical analysis of the data was performed using the Chi-square and Wilcoxon test as well as the two-factorial analysis of variance (ANOVA), the latter of which included repeated measurements for the factors group and the time of measurement. Results Therapeutic outcome: The data of all 30 patients in the control group and the 28 patients in the study group were analyzed. The remaining two animals in the study group were excluded. In one animal the attempt to perform the pyloroplasty was unsuccessful and the second animal was euthanatized following trauma. 22 animals of the study group (17 recovered and 5 improved) and 25 animals of the control group (21 recovered and 4 improved) were discharged home for further observation. The differences between both groups were not statistically significant. Three months after the procedure, 15 cows of the study group (53.6%) and 17 cows of the control group (56.7%) were at their home farm and utilized as normal. Two of the remaining 7 in the study group and three of the remaining 8 in the control group were culled because of disorders not related to the previous treatment (fertility disorders, mastitis, claw disorders). All patients that died or were euthanatized in the clinic (6 in the control group and 5 in the study group, respectively) showed severe lesions of the abomasum, i.e. ulcers and necrosis. Clinical and laboratory parameters: There were no statistically significant differences between the two groups regarding the progression of the clinical findings and the laboratory parameters that were assessed. Conclusion The impairment of propulsion of ingesta occurring in some patients presented with abomasal volvulus cannot be improved by enlargement of the pyloric canal using Heinecke Mikulicz’s Pyloroplasty. Thus, this relatively complex surgical procedure is not recommended as a routine method for the prophylaxis of these complications

Meeting End-to-End Deadlines in Real-Time Networks Using Software Defined Networking (SDN)

Network flows in Real-Time (RT) systems need to meet stringent end-to-end deadlines in order for such systems to operate safely and reliably. Today, such systems use custom or domain specific network system designs to meet end-to-end deadlines and other constraints of real-time flows. In this work we explore the design of real-time networks using common-off-the-shelf (COTS) components by leveraging Software-Defined Networking (SDN) paradigm. In particular, we explore the effectiveness of using i) spatially varying but locally static flow priorities and ii) the impact of using Least-Slack Prioritization on the performance of network path layout and provisioning algorithms. Specifically, we propose different heuristics for spatial variation of static flow priorities in a real-time network and empirically show that spatial variation of priorities can accommodate more real-time flows than simple static priorities. Further, we show that least-slack based flow priority assignment performs better than deadline monotonic priority assignment for multiple path layout algorithms considered in this work

Libya-United States Relations, 1969-1986

This thesis examines Libya-United States Relations from 1969 until 1986. The period between the September 1969 Revolution and 1986 saw an important development in the relationship between the two countries. The September Revolution marked a shift in the pattern of Libya-United States relations as Libya took a more independent approach to conducting its domestic affairs and establishing foreign relations not only with the United States, but with other countries as well. It was this shift in Libyan domestic and foreign policies that set a new trend in its relations with the United States. This study was based on a historical approach and the re-examination of secondary documents such as books, newspaper clippings, official publications and my own experience as a foreign affairs officer. The study discovered several important developments and factors that shaped Libya-United States Relation between 1969-1986. Firstly, relations between Libya and the United States deteriorated especially after the September 1969 Revolution when the leadership of the former passed over to Colonel Muammar Qadhafi, a military personnel, who brought in his personal style of leadership that was backed by popular Libyan support. Qadhafi's attempt to construct a new and truly independent Libya and make the country a key international player in the region were strongly met with resistance, especially from the United States which had grown use to its increasingly dominant role in the region and which had also gone unchallenged. Secondly, Libya' s firm stand on its national independence and its actions to remove foreign influences and domination triggered the start of a sour relation with the United States. This turn of relation was not augmented by the fact that Libya was also a strong proponent of the Arab nationalism and its undivided support for pan-African nationalism. As Libya's began to take a more dominant role in the region, the country was becoming increasingly viewed in negative light. United States' perception of Libya was beginning to be couched in terms such as "terrorists" or "sponsors" of terrorism on the international scale. Thirdly, the deterioration in the bilateral relations between the two countries was manifested by the trade volumes that plummeted especially in the post- 1 969 period. Before this period, relations between the two had been marked by friendly relations and was demonstrated by the presence of not only the American military personnel but also of a sizeable American business community, especially in Tripoli. Fourthly, the deteriorating relations between the two countries were attributed to several factors such as the American perception of Libya as a state that supported terrorists and terrorist acts and Libya's negative image that was being perpetrated by the western media and prominent personalities that were close to the American leadership. Lastly, this study ended in 1986 because this period represented the lowest ebb in Libya-United States relations. By this period, there was no formal relation as both countries withdrew diplomatic representations in each other's capital. Signs of better relations only seem to have resurfaced in the late 1990s. However, the extent to which this might develop further to benefit the peoples of the two countries remains to be seen. But this contemporary development in the Libya-United States relations is not within the scope of this study

Antibacterial Activity of Paracetamol, Trimethoprim/sulfamethoxazole, Azithromycin, and Ciprofloxacin

Paracetamol have indirect antibiotic activity and are commonly coadministered with antimicrobial therapy. This study aimed to assess the synergistic effect of Paracetamol to with Azithromycin, Trimethoprim/sulfamethoxazole and Ciprofloxacin against salmonella and Escherichia coli. In this study, Ciprofloxacin, Trimethoprim/sulfamethoxazole and Azithromycin was mixed paracetamol against salmonella and Escherichia coli. The results showed that the interaction between Paracetamol and Azithromycin, Trimethoprim/sulfamethoxazole and ciprofloxacin exhibited more in inhibitory potency against on Gram-negative salmonella and Escherichia coli. The combinations of Paracetamol with the Azithromycin and Trimethoprim/sulfamethoxazole showed significant inhibitory activity on the salmonella and Escherichia coli comparing to the inhibition activity showed from the tested antibiotics alone

Dynamic modeling and fuzzy logic control of a large building HVAC system

Energy and cost-efficient management of a building’s thermal properties requires heating, ventilation and air conditioning (HVAC) systems controllers to be working at optimal settings. However, many HVAC systems employ nonlinear time variances to deal with issues that affect the system’s optimal operation. The present work considers an HVAC system at Memorial University’s S. J. Carew Building which has been mathematically modeled using a state space multi-input and multi-output system (MIMO) approach for analyses and control system design. An IDA-ICE (Indoor Climate and Energy) simulation program has been applied for modeling the building, note that the four-story Carew Building includes an air-handling unit (AHU) on every floor. Compared with real data for one year’s (2016) power consumption, the simulated annual power consumption for the building shows good agreement. Based on that data, two scenarios are applied for building the system models. Scenario 1 considers the HVAC system as a single unit with energy consumption (kWh) as inputs and zonal temperature and CO2 concentrations as outputs. By employing the MATLAB system identification toolbox, a MIMO-based system forms the basis for a state space model. In the model for Scenario 1, there are eight main AHU inputs (hot water power usage and power usage) and eight main outputs (return airflow temperature and CO2 levels). The state feedback controller obtains good results for both responses rise time and stability. In Scenario 2, there are four AHUs in total. Each of this scenario’s AHUs features three main inputs (hot water, internal-to-internal air flow, and external-to-internal air flow) and three main outputs (static air pressure, CO2 levels, and temperature). In the first AHU (AHU1), we apply state-of-the-art fuzzy logic controllers (FLCs) to control fan speeds, CO2 concentrations, and temperature in the building in accordance with the flow rates for air and hot water. This strategy represents a novel approach for adapting FLCs by modifying fuzzy rule using the Simulink. The modified system shows improved levels of thermal comfort. The final part of the work presents the design for a supervisor fuzzy logic controller (SFLC) that can be applied to the entire S. J. Carew Building HVAC control. This SFLC features 24 inputs and 12 outputs and employs a state-space model that considers each AHU as an individual system. The SFLC detailed design and system simulation results are presented in this thesis

The challenges of massive open online courses (MOOC)- A preliminary review

Massive Open Online Course (MOOC) is one of the most recent innovations in education. It is a form of an open source learning sys- tem that offers free and short online courses to anyone who has access to the Internet.MOOC offers a lifelong learning opportunity and a number of ex- isting MOOC online platforms include edX, Coursera, Udacity, and Udemy.However, there are a number of problems and challenges in MOOC, among the major recurring issue is the consistently high dropout rate of MOOC learners.In this paper, we introduce a critical review of literature relating to MOOC dropout rates, bringing together existing findings on completion rates and analyses of several specific courses related to these organizations, which identify factors that correlate to the likelihood of dropout.Finally, we discuss our findings relating MOOC dropout rates, considering what factors are within the control of an MOOC provider and suggesting the most prom- ising avenues for improvement

Perceptions of Assistant Principals’ and Principals’ of Bahrain Government Schools about the Impact of the Bahrain Teachers College Educational Leadership Program on Their Performance

This article examines the perceptions of school assistant principals and principals who completed the Bahrain Teachers College higher diploma of education leadership program about its impact on their performance. The study sample consisted of 141 program graduates from 9- cohorts. A multilevel concept in measuring the impact of the educational leadership program on the graduates’ performance was employed. The framework consisted of 4 levels: self-learning, changing others, embedding changes in school practices and sustainability of change and scaling up the school performance. The study questionnaire was designed on the basis of this framework. Results show that the Educational Leadership program positively affected its graduates’ performance in the 4 levels. The majority of the program graduates agreed that the program positively affected their personal qualities, leadership styles and practices to support school development, school staff, students’ performance and school ranking. The majority of the program graduates also agreed that the program positively affected their skills in dealing with curriculum innovations, professional development, research, strategic planning, staff appraisal, communication with community, using ICT, improving students’ learning and applying educational ethics.     Keywords: Education Leadership, School Principals’ Performance, Leadership Styles, School Practices, Leadership Skill

Prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) among Staphylococcus aureus collection at Sebha medical center

The prevalence of multidrug-resistant Staphylococcus aureus has increased during the last few years in healthcare facilities, and methicillin-resistant Staphylococcus (MRSA) in particular has emerged as a serious nosocomial pathogen because it is difficult to destroy and treat. Therefore, this study was carried on to find out the frequency of MRSA among S. aureus isolates as well as to study their susceptibility profile. In this study, 43 strains of S. aureus were recovered from different departments at Sebha medical center and their antibiotic resistance profile was studied using Kirby Bauer disc diffusion method. Out of all 43 isolates, 16% were detected as MRSA using cefoxitin disk test. The strains that are resistant to erythromycin were further tested for inducible clindamycin resistance (ICR) using D-test. In this study, two strains showed ICR phenotype. While all isolates were 100% sensitive to vancomycin, the majority of isolates were resistant to ß-lactam group antibiotics. We observed that 14% of all isolates were resistant to ß-lactamase inhibitor. The response of S. aureus isolates to other antibiotics e.g. quinolone, aminoglycosides, tetracycline and macrolides was variable. In our study, it seemed to be vancomycin is the only antibiotic that still keeping its potency and it can be used for treatment of infections caused by multidrug-resistant MRSA