8,062 research outputs found
Implications of the Improvement of Teaching Quality for Professional Development (PD) of Academics at the Colleges of Applied Sciences (CASs) in the Sultanate of Oman
No full textThe Oman Accreditation Council (OAC), which is called later the Oman Academic Accreditation Authority (OAAA), designed a higher education institution (HEI) Quality Assurance (QA) framework for Omani public and private Higher Education Institutions (HEIs), starting with a quality audit process in 2008. The Colleges of Applied Sciences (CASs), as a public HEI, are required to ensure the quality of all services and activities to meet particular national standards (specified in the framework) in order to gain a HEI and programme certificate. In line with a quality audit scope, the quality of the fields of PD and related teaching quality should be ensured and enhanced by the promotion and contribution of the former field to the maintenance and improvement of the latter one.
The chief purpose of this study was to identify the uptake and implications of the growing requirement to improve teaching quality and the PD of academics at the CASs in the Sultanate of Oman especially in the context of the application of the QA framework. The study focused on examining the academics’ participation in professional development programmes (PDPs) and current perceptions of PD with respect to the improvement of teaching quality improvement at these colleges. The current study also dealt with a reorganization and prioritization of academics’ PD needs, barriers to effective PD, and factors to enhance PD of academics regarding teaching quality improvement in the colleges.
Based on the purpose and research objectives, the current study adopted both positivist (quantitative) and interpretive (qualitative) research paradigms. Because the study perused quantitative and qualitative data regarding certain variables, it chose a mixed-research design. The researcher designed survey questionnaire to collect quantitative data and a semi-structured interview and a focus group discussion to probe and interpret quantitative findings. After fulfillment of the validity and reliability measurements, a self-completion questionnaire was distributed to a stratified random sample of academics (170) over the six CASs. A total of 150 questionnaires (out of 170) were completed and returned and the response-rate reached 88.2%. The quantitative data was analyzed by appropriate analysis using the Statistical Package for Social sciences (SPSS), while the qualitative data was analyzed by appropriate qualitative analysis.
The findings of the study showed that the level of academics’ participation in PDPs to improve teaching quality in the last two years in the CASs seems to be unsatisfactorily low. The current perceptions of the PD situations in the colleges, relating to teaching quality improvement, signified a shortage in the number of available PDPs and/or a discouragement of academics’ participation in these programmes in the last two years. The study also revealed all the 22 PD needs of academics regarding the improvement of teaching quality are significantly demanded by participants; the higher rated needs focused on a development of ‘student centred’ skills, such as critical thinking and problem-solving skills.
Furthermore, the study illustrated that the highest significant perceived barriers to effective PD in the CASs, as related to teaching quality improvement, focus on a lack of a clear institutional PD policy and a lack of appropriately systematic PD plans. The study also revealed all 10 perceived factors to enhance PD regarding teaching quality improvement are very important. The most significant factors represented and stressed particular problematic issues (the high rated barriers) and a reduction of a heavy workload to enhance academics’ participation in PD regarding the improvement of teaching quality.
Conclusions drawn from the discussion of the findings of study include a lack of a clear PD policy at national and institutional levels and absence of a particular authority/unit concerning PD issues in Omani HEIs. The two problematic issues resulted in a lack of systematic and realistic PD plans in the CASs, involving a lack of academics’ involvement in PD plans, a misconnection of academics’ PD needs to PD, inappropriate facilities and resources allocation, and inappropriate evaluation processes of PD. In addition, the conclusions also include that PD of academics regarding the improvement of teaching quality in the colleges requires more attention and focus to manage particular significant issues perceived by participants as both barriers and potential facilitators relating to PD of academics.
Based on identified conclusions, particular implications for policy and practice to enhance PD to improve teaching quality were set at three levels: governmental, institutional, and individual. Moreover, achievements of the current study according to the research questions were identified and contributions of the study to the fields of PD, teaching quality, and the context of QA and quality audit in HE were addressed. Based on the findings and conclusions, particular directions and recommended issues were suggested to be studied by further research to benefit the enhancement of PD and related teaching quality improvement
Distribution and density of harbour popoises in Dutch North Sea waters
No full textAerial surveys were conducted to investigate harbour porpoise density and distribution in Dutch waters. Surveys were conducted following standard line transect distance sampling methodology on tracklines providing a representative coverage of the study area which ranged from the Dutch coast to about 120 km offshore thus covering about half of the Dutch EEZ. Within this overall study area two sub-areas were defined. One sub-area (from Texel to the German border) was covered in on 29 November 2008 and 3 April 2009. Density was 1.02 animals per km² during the November survey and 0.52 animals per km² during the April survey. An overall survey, covering both sub-areas, was conducted on 3 February, 18 March and 3 April 2009. The resulting density was 1.12 animals per km². This corresponds to an estimate of harbour porpoise abundance for this study area of 36 825 animals (95% C.I. 19 090 – 68 130; 0.33 C.V.). Distribution patterns of porpoises in the surveys waters were patchy and seemed variable between surveys. Applying this abundance estimate, a range of potential mortality limits were calculated for the Dutch harbour porpoises
Identification, binding, and structural characterization of single domain anti-PD-L1 antibodies inhibitory of immune regulatory proteins PD-1 and CD80
No full textProgrammed death-ligand 1 (PD-L1) is a key immune regulatory protein that interacts with programmed cell death protein 1 (PD-1), leading to T-cell suppression. Whilst this interaction is key in self-tolerance, cancer cells evade the immune system by overexpressing PD-L1. Inhibition of the PD-1/PD-L1 pathway with standard monoclonal antibodies has proven a highly effective cancer treatment; however, single domain antibodies (VHH) may offer numerous potential benefits. Here, we report the identification and characterization of a diverse panel of 16 novel VHHs specific to PD-L1. The panel of VHHs demonstrate affinities of 0.7 nM to 5.1 μM and were able to completely inhibit PD-1 binding to PD-L1. The binding site for each VHH on PD-L1 was determined using NMR chemical shift perturbation mapping and revealed a common binding surface encompassing the PD-1–binding site. Additionally, we solved crystal structures of two representative VHHs in complex with PD-L1, which revealed unique binding modes. Similar NMR experiments were used to identify the binding site of CD80 on PD-L1, which is another immune response regulatory element and interacts with PD-L1 localized on the same cell surface. CD80 and PD-1 were revealed to share a highly overlapping binding site on PD-L1, with the panel of VHHs identified expected to inhibit CD80 binding. Comparison of the CD80 and PD-1 binding sites on PD-L1 enabled the identification of a potential antibody binding region able to confer specificity for the inhibition of PD-1 binding only, which may offer therapeutic benefits to counteract cancer cell evasion of the immune system
Identification, binding, and structural characterization of single domain anti-PD-L1 antibodies inhibitory of immune regulatory proteins PD-1 and CD80
No full textProgrammed death-ligand 1 (PD-L1) is a key immune regulatory protein that interacts with programmed cell death protein 1 (PD-1), leading to T-cell suppression. Whilst this interaction is key in self-tolerance, cancer cells evade the immune system by overexpressing PD-L1. Inhibition of the PD-1/PD-L1 pathway with standard monoclonal antibodies has proven a highly effective cancer treatment; however, single domain antibodies (VHH) may offer numerous potential benefits. Here, we report the identification and characterization of a diverse panel of 16 novel VHHs specific to PD-L1. The panel of VHHs demonstrate affinities of 0.7 nM to 5.1 μM and were able to completely inhibit PD-1 binding to PD-L1. The binding site for each VHH on PD-L1 was determined using NMR chemical shift perturbation mapping and revealed a common binding surface encompassing the PD-1–binding site. Additionally, we solved crystal structures of two representative VHHs in complex with PD-L1, which revealed unique binding modes. Similar NMR experiments were used to identify the binding site of CD80 on PD-L1, which is another immune response regulatory element and interacts with PD-L1 localized on the same cell surface. CD80 and PD-1 were revealed to share a highly overlapping binding site on PD-L1, with the panel of VHHs identified expected to inhibit CD80 binding. Comparison of the CD80 and PD-1 binding sites on PD-L1 enabled the identification of a potential antibody binding region able to confer specificity for the inhibition of PD-1 binding only, which may offer therapeutic benefits to counteract cancer cell evasion of the immune system
Fullerene-like WS<sub>2</sub> supported Pd catalyst for hydrogen evolution reaction
No full textHydrogen is the most desirable green energy carrier and electrocatalytic hydrogen evolution reaction (HER) from water is a promising route for hydrogen production. The search for efficient, low-cost HER catalysts is a challenging and attracting topic. In this work, we report that inorganic fullerene-like WS2 supported Pd nanoparticles (Pd/WS2), with Pd loading of 0.76 wt%, are active for electrocatalytic HER conducted in 0.5 M H2SO4 solution, with overpotential at 10 mA cm−2 current density of ~130 mV and Tafel slope of 82.4 mV dec−1, which is comparable to that of Pt/WS2 (0.88 wt% Pt loading) with higher costs. Characteristic results indicate that WO3 impurities were in-situ produced on the WS2 surface and the Pd NPs are primarily located inside the WS2 nanocages. Contrasting experiments suggest that the WO3 impurities play a crucial role in generating Hads intermediate and the Pd NPs are active sites of H2 production, and a reaction mechanism is proposed. The Pd/WS2 catalyst also shows good long-term stability owing to the location of Pd NPs inside the WS2 cages. The high HER activity, low costs and good stability make the Pd catalyst a potential alternative to Pt catalyst for HER.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Micro and Nano Engineerin
Taxonomy of the fouling cheilostome bryozoans, Schizoporella unicornis, (Johnston) and Schizoporella errata (Waters)
No full textFigure 1. (A–D) Images of Wood's Pliocene specimen from the Coralline Crag, Suffolk (NHM B1675) described in Busk (1859). (A) Group of autozooids at growing edge of colony within small bivalve shell. (B) Autozooids exhibiting deep V-shaped sinus. (C) Frontal shield with paired avicularia and deep V-shaped sinus. (D) Detail of primary orifice and sinus. (E, F) Lectotype of Schizoporella unicornis [NHM 1847.16.174 (a)] bleached portion. (E) Group of autozooids at the distal edge of colony with adventitious avicularia, paired, single or absent. (F) Ovicellate autozooids showing radially aligned scalloped grooves. Scale bars: 500 µm (A); 250 µm (B); 100 µm (C, E); 50 µm (D,F).Published as part of Tompsett, Scott, Porter, Joanne S. & Taylor, Paul D., 2009, Taxonomy of the fouling cheilostome bryozoans Schizoporella unicornis (Johnston) and Schizoporella errata (Waters), pp. 2227-2243 in Journal of Natural History 43 (35-36) on page 2231, DOI: 10.1080/00222930903090140, http://zenodo.org/record/521715
Microbial acetone oxidation in coastal seawater
Full text linkAcetone is an important oxygenated volatile organic compound in the troposphere where it influences the oxidising capacity of the atmosphere. However, the air-sea flux is not well quantified, in part due to a lack of knowledge regarding which processes control oceanic concentrations, and, specifically whether microbial oxidation to CO2 represents a significant loss process. We demonstrate that 14C labelled acetone can be used to determine microbial oxidation to 14CO2. Linear microbial rates of acetone oxidation to CO2 were observed for between 0.75-3.5 hours at a seasonally eutrophic coastal station located in the western English Channel (L4). A kinetic experiment in summer at station L4 gave a Vmax of 4.1 pmol L-1 h-1, with a Km constant of 54 pM. We then used this technique to obtain microbial acetone loss rates ranging between 1.2-42 pmol L-1 h-1 (monthly averages) over an annual cycle at L4, with maximum rates observed during winter months. The biological turnover time of acetone (in situ concentration divided by microbial oxidation rate) in surface waters varied from ~3 days in February 2011, when in situ concentrations were 3 ± 1 nM, to >240 days in June 2011, when concentrations were more than 2 fold higher at 7.5 ± 0.7 nM. These relatively low marine microbial acetone oxidation rates, when normalised to in situ concentrations, suggest that marine microbes preferentially utilise other oxygenated volatile organic compounds such as methanol and acetaldehyde
Embracing Monogenic Parkinson's Disease: The MJFF Global Genetic PD Cohort
No full textBackground: As gene-targeted therapies are increasingly being developed for Parkinson's disease (PD), identifying and characterizing carriers of specific genetic pathogenic variants is imperative. Only a small fraction of the estimated number of subjects with monogenic PD worldwide are currently represented in the literature and availability of clinical data and clinical trial-ready cohorts is limited. Objective: The objectives are to (1) establish an international cohort of affected and unaffected individuals with PD-linked variants; (2) provide harmonized and quality-controlled clinical characterization data for each included individual; and (3) further promote collaboration of researchers in the field of monogenic PD. Methods: We conducted a worldwide, systematic online survey to collect individual-level data on individuals with PD-linked variants in SNCA, LRRK2, VPS35, PRKN, PINK1, DJ-1, as well as selected pathogenic and risk variants in GBA and corresponding demographic, clinical, and genetic data. All registered cases underwent thorough quality checks, and pathogenicity scoring of the variants and genotype–phenotype relationships were analyzed. Results: We collected 3888 variant carriers for our analyses, reported by 92 centers (42 countries) worldwide. Of the included individuals, 3185 had a diagnosis of PD (ie, 1306 LRRK2, 115 SNCA, 23 VPS35, 429 PRKN, 75 PINK1, 13 DJ-1, and 1224 GBA) and 703 were unaffected (ie, 328 LRRK2, 32 SNCA, 3 VPS35, 1 PRKN, 1 PINK1, and 338 GBA). In total, we identified 269 different pathogenic variants; 1322 individuals in our cohort (34%) were indicated as not previously published. Conclusions: Within the MJFF Global Genetic PD Study Group, we (1) established the largest international cohort of affected and unaffected individuals carrying PD-linked variants; (2) provide harmonized and quality-controlled clinical and genetic data for each included individual; (3) promote collaboration in the field of genetic PD with a view toward clinical and genetic stratification of patients for gene-targeted clinical trials. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.Full Tex
Total Maximum Daily Load Document: Jeffries Creek and Tributaries - Stations PD-167, PD-256, PD-065, PD-230, RS-07205, PD-035, and PD-231
Full text linkThe federal Clean Water Act (CWA) directs each state to review the quality of its waters every two years to determine if water quality standards are being met. A Total Maximum Daily Load (TMDL) is a written plan and analysis to determine the maximum pollutant load a waterbody can receive and still meet applicable water quality standards. This TMDL document details Escherichia coli Bacteria, Indicator for Pathogens for Jeffries Creek and Tributaries: Stations: PD-167, PD-256, PD-065, PD-230, RS-07205, PD-035, and PD-231. Hydrologic Unit Codes: 030402010901, 030402010902, 030402010903, 030402010904, and 030402010905
Nanocatalisadores metálicos de paládio e prata estabilizados com novos líquidos iônicos piridínicos para aplicação em reações de Heck e redução
Full text linkTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2015.Este trabalho foi dividido em: (i) síntese de novos líquidos iônicos (LIs) piridínicos para utilização na estabilização de nanopartículas de prata (Ag-NPs) para aplicação na reação de redução do p-nitrofenol (NIP) e (ii) a introdução da ciclização do N-(o-iodobenzoil)-3-metilindol (MIAc), como modelo de reação de Heck para avaliação in situ, por espectroscopia UV-visível (UV-vis), da atividade de catalisadores a base de paládio molecular ou coloidal. Nove LIs foram sintetizados variando-se a cadeia alquílica ligada ao nitrogênio piridínico (metil, butil e octil) e contra-íons (haletos, tetrafluoroborato (BF4) e bis(trifluorometilsulfonil)imidato (NTf2)) e utilizados na estabilização de Ag-NPs. Para comparar os nove sistemas Ag-NPs/LI, verificou-se sua atividade catalítica na reação de redução do NIP, cujo progresso é facilmente monitorado por UV-vis. Todos os nanocatalisadores apresentaram atividade na redução do NIP sendo que, em geral, as maiores constantes de velocidade foram obtidas quando LIs metilados foram utilizados como estabilizante. Na reação de ciclização do MIAc, três sistemas catalíticos foram testados: nanopartículas de paládio (Pd-NPs/LI-Me(I)) pré-formadas e estabilizadas pelo LI N-metilpiridínico (LI-Me(I)); Pd(OAc)2 e Pd(OAc)2 com adição de LI-Me(I) (Pd(OAc)2/LI-Me(I)). Diversos experimentos foram realizados como variação da quantidade do catalisador, da concentração e natureza da base, do solvente e do LI, além de análises por microscopia eletrônica de transmissão (TEM) em diferentes tempos de reação e envenenamento com Hg. Após essa série de experimentos, pode-se dizer que a ciclização do MIAc foi introduzida com êxito como modelo de reação de Heck uma vez que seu progresso foi acompanhado in situ por UV-vis facilitando a realização de diversos experimentos para obtenção dos parâmetros cinéticos TON (mol de catalisador/mol de produto) e TOF (TON/tempo), com os quais comparou-se a atividade e aplicabilidade de sistemas catalíticos a base de paládio. Além disso, demonstrou ser uma reação relativamente branda ocorrendo em meio aquoso, na ausência de atmosfera inerte e a 80 ºC. O sistema Pd(OAc)2/LI-Me(I), com 1x10-3 mmol L-1 de LI-Me(I), resultou nos maiores parâmetros TON e TOF e maior conversão ao produto de ciclização.Abstract : The present work is divided in: (i) synthesis of new pyridinium ionic liquids (LIs) to use as stabilizing agents of silver nanoparticles (Ag-NPs), whose application was the reduction reaction of p-nitrophenol (NIP) and (ii) the introdution of (2-iodophenyl)(3-methyl-1H-indol-1-yl)methanone (MIAc) ciclization as a model reaction, for the in situ evaluation by UV-vis Spectroscopy (UV-vis) of Pd catalysts based on molecular or colloidal palladium. Nine LIs were synthesized modifying the alkyl chain bounded to the pyridine nitrogen (methyl, butyl and octyl) and the counteranion (halides, tetrafluoroborate (BF4-) and bis(trifluoromethylsulfonyl)imidate (NTf2-)). To compare the nine Ag-NPs/LI systems, their catalytic activity was evaluated in the NIP reduction reaction, whose progress can be easily monitored by UV-vis. All Ag-NPs/LI catalyst showed a good catalytic activity for the NIP reduction but, in general, the highest rate constants were obtained with methylic LIs. For the MIAc ciclization, three catalytic systems were evaluated: as-formed palladium nanoparticles (Pd-NPs/LI-Me(I)) stabilized by N-methylpyridinic LI, Pd(OAc)2, and Pd(OAc)2 with LI-Me(I) addition (Pd(OAc)2/LI-Me(I)). A series of experiments was carried out including varying the amount of catalyst, the concentration and nature of the base, solvent, and LI, analysis by transmission electronic microscopy (TEM) at different times of the reaction and poisoning tests with Hg. After this series of experiments, it can be said that the cyclization of MIAc was successfully introduced as a model for Heck reaction since its progress was easily monitored in situ by UV-vis, facilitating the implementation of several experiments and obtaining the kinetic parameters TON (mol of product/mol of catalyst) and TOF (TON/time), in which the activity and applicability of the catalytic systems could be compared. Furthermore, the reaction was carried out at relatively mild conditions once it occurs in aqueous medium, in the absence of inert atmosphere, and at 80 ° C. The Pd(OAc)2/LI-Me(I) system with 1x10-3 mmol L-1 of LI-Me(I) resulted in both, highest kinetic parameters TON and TOF and ciclization product conversion
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