21 research outputs found
Understanding the Agency of Diversity Managers: A Relational and Multilevel Investigation.
No full textPhDThis thesis aims to provide a critical realist account of diversity managers' agency,
incorporating a critique of the existing diversity management research. A multilevel and
relational analytical framework is offered in order to understand diversity managers'
agency. The framework interpreted and operationalised Bourdieu's key concepts,
`field', `habitus', `capitals' and `strategies' in the organisational context, for exploring
and explaining macro, meso and micro level influences on the agency of diversity
managers.
The macro-social field of diversity management is mapped out by analysing data from
an online national survey completed by diversity managers in the UK, and in-depth
interviews with diversity managers of large public and private sector organisations.
Then, findings of an extensive case study of Ford Motor Company, which includes
company documentation and interviews with the company's diversity managers, are
introduced to examine meso-organisational and micro-individual dynamics of diversity
managers' agency.
The analysis of the findings revealed that the agency of diversity managers is
multilayered and complex. Whilst the boundaries of this agency are drawn by the deeply
seated structures and mechanisms which are embedded in the fabric of social and
organisational lives, diversity managers own varying degrees of social, cultural and
symbolic capitals which are potential sources of power and influence, and they utilise
strategies in order to activate this potential and widen the scope of their agency.
The thesis addresses the limitations in diversity management literature, which are
associated with dualisms of agency and structure, and qualitative and quantitative
methods. It makes theoretical and methodological contribution by offering original
empirical evidence generated through a multi-method strategy and analysing diversity
managers' agency at the interplay of agentic and structural dynamics. It also offers
policy makers at organisational and national levels a realistic understanding of diversity
management processes that may inform design of more effective and progressive
policies and initiatives.School of Business and Management Queen Mary University
Development of independent MU/treatment time verification algorithm for non-IMRT treatment planning: A clinical experience
No full textBöbrek üstü bezi metastazlarında stereotaktik beden radyoterapisinin hedef hacim doz homojenitesine etkisinin değerlendirilmesi
No full textBu tez çalışmasında, böbrek üstü bezi metastazı olan 9 hastanın 12 adet lezyonu için tedavi öncesi çekilen bilgisayarlı tomografi kesit görüntüleri kullanılarak, dinamik konformal arkl (DCA) ve sabit gantri açılı konformal demet (FBC) teknikleri ile stereotaktik beden radyoterapisi (SBRT) tedavi planları yapılmıştır. Elde edilen veriler hedef hacim doz homojeniteleri ile kritik organ dozları açısından değerlendirilmiştir. DCA tekniği ile yapılan planlarda 2cc'lik 12 ile 14 adet arasında arklar, FBC tekniği ile yapılan tedavi planlarında ise 10cc aralıklarla yerleştirilmiş 24 ile 27 adet arasında demet kullanılmıştır. Her iki planlama tekniği için de günlük fraksiyon dozu 10 Gy olup, hedef hacim için planlanan tedavi dozu 30 Gy'dir. Üç fraksiyonluk tedavi şeması için kritik organların tolerans dozları, spinal kord için maksimum 18 Gy, böbrek için eşik doz 15 Gy (en az 200cc böbrek hacmi eşik doz altında kalmalı) ve karaciğer için eşik doz 15 Gy (en az 700cc karaciğer hacmi eşik doz altında kalmalı) olarak belirlenmiştir. Hedef hacim doz homojeniteleri açısında DCA tekniği FBC tekniğinden % 0,3 daha iyi sonuç vermiştir. DCA tekniği spinal kord için, maksimum dozu % 4,3 azaltmıştır. FBC tekniğine göre DCA tekniğinin ipsilateral böbrek için ortalama dozu % 1,3 ve V15 hacmini % 8,8 azalttığı, kontralateral böbrek için ise ortalama dozu % 0,8 azalttığı bulunmuştur. FBC tekniğine göre DCA tekniğinin ipsilateral karaciğer için ortalama dozu % 1,1 ve V15 hacmini % 1,2 azalttığı, kontralateral karaciğerin için ise maksimum dozu % 4,3 azaltıp, ortalama dozu % 9,3 arttırdığı görülmüştür. Çalışma sonucunda hedef hacim doz homojenitelerinin daha iyi, kritik organ dozlarının daha düşük olmasına neden olan DCA tekniğinin, SBRT planlarında uygulanmasının FBC tekniğinden daha uygun olduğu sonucuna ulaşılmıştır. Abstract In this thesis, stereotactic body radiation therapy treatment plans were done for 9 patients having 12 adrenal gland lesions, with dynamic conformal arc (DCA) and fixed beam conformal (FBC) planning techniques, using cross-sectional computed tomography images. Plans were evaluated in respect to target volume dose homogeneities and critical organ doses. In DCA plans, 20cc arcs were used in the number of 12 to 14, and in FBC plans, 24 to 27 beams with 10cc separations were used. For each planning techniques, total prescribed dose for target volume is 30 Gy with three fractions of 10 Gy. Dose constraints for critical organs were determined as 18 Gy maximum for spinal cord, 15 Gy threshold for kidney (at least 200cc kidney volume should remain below threshold), 15 Gy threshold for liver (at least 700cc liver volume should remain below threshold). DCA technique provided % 0,3 better target volume dose homogeneity than FBC. In DCA plans, maximum spinal cord dose decreased by % 4,3 with respect to FBC plans. By comparison with FBC techniques, DCA techniques resulted in %1,3, lower mean dose and % 8,8 lower V15 volume for ipsilateral kidney and % 0,8 lower mean dose for contralateral kidney. For ipsilateral liver % 1,1 lower mean dose, and % 1,2 lower V15 volume; and for contralateral liver % 4,3 lower maximum dose and % 9,3 higher mean dose obtained in DCA plans in comparison to FBC plans. It is found that DCA technique, which provide better target volume dose homogeneity and lower critical organ doses, is more appropriate in SBRT treatment plans than FBC techniqu
Böbrek üstü bezi metastazlarında stereotaktik beden radyoterapisinin hedef hacim doz homojenitesine etkisinin değerlendirilmesi
No full textBu tez çalışmasında, böbrek üstü bezi metastazı olan 9 hastanın 12 adet lezyonu için tedavi öncesi çekilen bilgisayarlı tomografi kesit görüntüleri kullanılarak, dinamik konformal arkl (DCA) ve sabit gantri açılı konformal demet (FBC) teknikleri ile stereotaktik beden radyoterapisi (SBRT) tedavi planları yapılmıştır. Elde edilen veriler hedef hacim doz homojeniteleri ile kritik organ dozları açısından değerlendirilmiştir.DCA tekniği ile yapılan planlarda 2cc'lik 12 ile 14 adet arasında arklar, FBC tekniği ile yapılan tedavi planlarında ise 10cc aralıklarla yerleştirilmiş 24 ile 27 adet arasında demet kullanılmıştır.Her iki planlama tekniği için de günlük fraksiyon dozu 10 Gy olup, hedef hacim için planlanan tedavi dozu 30 Gy'dir. Üç fraksiyonluk tedavi şeması için kritik organların tolerans dozları, spinal kord için maksimum 18 Gy, böbrek için eşik doz 15 Gy (en az 200cc böbrek hacmi eşik doz altında kalmalı) ve karaciğer için eşik doz 15 Gy (en az 700cc karaciğer hacmi eşik doz altında kalmalı) olarak belirlenmiştir.Hedef hacim doz homojeniteleri açısında DCA tekniği FBC tekniğinden % 0,3 daha iyi sonuç vermiştir. DCA tekniği spinal kord için, maksimum dozu % 4,3 azaltmıştır. FBC tekniğine göre DCA tekniğinin ipsilateral böbrek için ortalama dozu % 1,3 ve V15 hacmini % 8,8 azalttığı, kontralateral böbrek için ise ortalama dozu % 0,8 azalttığı bulunmuştur. FBC tekniğine göre DCA tekniğinin ipsilateral karaciğer için ortalama dozu % 1,1 ve V15 hacmini % 1,2 azalttığı, kontralateral karaciğerin için ise maksimum dozu % 4,3 azaltıp, ortalama dozu % 9,3 arttırdığı görülmüştür.Çalışma sonucunda hedef hacim doz homojenitelerinin daha iyi, kritik organ dozlarının daha düşük olmasına neden olan DCA tekniğinin, SBRT planlarında uygulanmasının FBC tekniğinden daha uygun olduğu sonucuna ulaşılmıştır. AbstractIn this thesis, stereotactic body radiation therapy treatment plans were done for 9 patients having 12 adrenal gland lesions, with dynamic conformal arc (DCA) and fixed beam conformal (FBC) planning techniques, using cross-sectional computed tomography images. Plans were evaluated in respect to target volume dose homogeneities and critical organ doses.In DCA plans, 20cc arcs were used in the number of 12 to 14, and in FBC plans, 24 to 27 beams with 10cc separations were used. For each planning techniques, total prescribed dose for target volume is 30 Gy with three fractions of 10 Gy. Dose constraints for critical organs were determined as 18 Gy maximum for spinal cord, 15 Gy threshold for kidney (at least 200cc kidney volume should remain below threshold), 15 Gy threshold for liver (at least 700cc liver volume should remain below threshold).DCA technique provided % 0,3 better target volume dose homogeneity than FBC. In DCA plans, maximum spinal cord dose decreased by % 4,3 with respect to FBC plans. By comparison with FBC techniques, DCA techniques resulted in %1,3, lower mean dose and % 8,8 lower V15 volume for ipsilateral kidney and % 0,8 lower mean dose for contralateral kidney. For ipsilateral liver % 1,1 lower mean dose, and % 1,2 lower V15 volume; and for contralateral liver % 4,3 lower maximum dose and % 9,3 higher mean dose obtained in DCA plans in comparison to FBC plans.It is found that DCA technique, which provide better target volume dose homogeneity and lower critical organ doses, is more appropriate in SBRT treatment plans than FBC technique
Development of Independent MU/Treatment Time Verification Algorithm for Non-IMRT Treatment Planning: A Clinical Experience
No full textThe aim of this study is to develop an algorithm for independent MU/treatment time (TT) verification for non-IMRT treatment plans, as a part of QA program to ensure treatment delivery accuracy. Two radiotherapy delivery units and their treatment planning systems (TPS) were commissioned in Liv Hospital Radiation Medicine Center, Tbilisi, Georgia. Beam data were collected according to vendors' collection guidelines, and AAPM reports recommendations, and processed by Microsoft Excel during in-house algorithm development. The algorithm is designed and optimized for calculating SSD and SAD treatment plans, based on AAPM TG114 dose calculation recommendations, coded and embedded in MS Excel spreadsheet, as a preliminary verification algorithm (VA). Treatment verification plans were created by TPSs based on IAEA TRS 430 recommendations, also calculated by VA, and point measurements were collected by solid water phantom, and compared. Study showed that, in-house VA can be used for non-IMRT plans MU/TT verifications
Familial Spontaneous Coronary Artery Dissection Involving the Left Main Coronary Artery in a Young Male: A Case Report
No full textSpontaneous coronary artery dissection (SCAD) is a rare but important cause of acute coronary syndrome, particularly in young patients without conventional risk factors. While often sporadic, familial clustering has been increasingly recognized, indicating a genetic predisposition. We report a case of a 33-year-old male presenting with acute chest pain and ST-segment elevation. Coronary angiography showed spontaneous dissection with a large thrombus burden involving the distal left main coronary artery and extending into the proximal left anterior descending artery and circumflex artery. The patient had a family history of SCAD involving 2 siblings. Given the high thrombus burden and risk of procedural complications, a conservative approach was chosen. Management included tirofiban infusion, dual antiplatelet therapy, and anticoagulation. Intravascular ultrasound confirmed thrombus and intramural hematoma. Follow-up showed near-complete healing. Genetic testing identified a heterozygous TTN gene variant in the patient and his brother, a gene associated with cardiomyopathies. In conclusion, this case emphasizes the potential familial nature of SCAD and suggests a possible, previously unrecognized, association between TTN gene mutations and coronary dissection, indicating that conservative management with antiplatelet and anticoagulant therapy may be effective even in complex SCAD cases with high thrombus burden
Exploring the politics of linguistic difference: the construction of language requirements for migrants in jobs traditionally conducted by local native speakers
No full textWhile linguistic difference has been identified as an organizational source of disadvantage for migrants, the construction of language requirements in relation to which these differences emerge has rarely been examined. Yet, this is key to understand the politics of difference. Taking a social constructionist approach and relying on the concept of the ideal worker, this article analyzes a case study of an organization that hires migrants for jobs that used to be conducted by local native speakers. This research shows how conflicting constructions of language requirements may emerge in relation to different contextual causal powers. This might lead migrants to be constructed as different and not different from contrasting ideal worker notions, resulting in their simultaneous inclusion and marginalization in jobs at the bottom of the labour market. Moreover, this conflict generates the notion of the ideal non-ideal worker, which may produce a hierarchical differentiation within the category of migrant workers.This work is based on the PhD project of the first author, which was funded by BOF New initiatives (Universiteit Hasselt), nr. BOF17NI03.
We would like to thank the Special Issue Editors and anonymous reviewers for their helpful and supportive comments. Moreover, we would like to express our appreciation for the valuable feedback that was provided by Ahu Tatli, Marieke van den Brink, Patrizia Zanoni and Robert MacKenzie and are grateful for the support provided by Sabine Heulsen. Finally, we would also like to thank all respondents for their collaboration
Report Title: Selective NOx Recirculation for Stationary Lean-Burn Natural Gas Engines Type of Report: Technical Progress Report (Annual) Reporting Period Start
No full textAbstract The research program conducted at the Center for Alternative Fuels, Engine and Emissions (CAFEE) at West Virginia University is directed towards the verification and optimization of an approach to remove oxides of nitrogen (NOx) from the exhaust gas of stationary lean-burn natural gas engines. This program is sponsored by the US Department of Energy, National Energy Technology Laboratory (NETL) under contract number: DE-FC26-02NT41608. Selective NOx Recirculation (SNR) involves cooling the engine exhaust gas and then adsorbing the oxides of nitrogen (NOx) from the exhaust stream, followed by the periodic desorption of NOx. By returning the desorbed, concentrated NOx into the engine intake and through the combustion chamber, a percentage of the NOx is -decomposed during the combustion process. An initial study of NOx decomposition during lean-burn combustion was concluded in 2004 using a 1993 Cummins L10G 240hp natural gas engine. It was observed that the air/fuel ratio, injected NO (nitric oxide) quantity and engine operating points affected NOx decomposition rates of the engine. Chemical kinetic modeling results were also used to determine optimum NOx decomposition operating points and were published in the 2004 annual report. A NOx decomposition rate of 27% was measured from this engine under lean-burn conditions while the software model predicted between 35-42% NOx decomposition for similar conditions. A later technology 1998 Cummins L10G 280hp natural gas engine was procured with the assistance of Cummins Inc. to replace the previous engine used for 2005 experimental research. The new engine was equipped with an electronic fuel management system with closed-loop control that provided a more stable air/fuel ratio control and improved the repeatability of the tests. The engine was instrumented with an in-cylinder pressure measurement system and electronic controls, and was adapted to operate over a range of air/fuel ratios. The engine was connected to a newly commissioned 300hp alternating current (AC) motoring dynamometer. The second experimental campaign was performed to acquire both stoichiometric and slightly rich (0.97 lambda ratio) burn NOx decomposition rates. Effects of engine load and speed on decomposition were quantified, but Exhaust Gas Recirculation (EGR) was not varied independently. Decomposition rates of up to 92% were demonstrated. Following recommendations at the 2004 ARES peer review meeting at Argonne National Laboratories, iniv cylinder pressure was measured to calculate engine indicated mean effective pressure (IMEP) changes due to NOx injections and EGR variations, and to observe conditions in the cylinder. The third experimental campaign gathered NOx decomposition data at 800, 1200 and 1800 rpm. EGR was added via an external loop, with EGR ranging from zero to the point of misfire. The air/fuel ratio was set at both stoichiometric and slightly rich conditions, and NOx decomposition rates were calculated for each set of runs. Modifications were made to the engine exhaust manifold to record individual exhaust temperatures. The three experimental campaigns have provided the data needed for a comprehensive model of NOx decomposition during the combustion process, and data have confirmed that there was no significant impact of injected NO on in-cylinder pressure. The NOx adsorbtion system provided by Sorbent Technologies Corp. (Twinsburg, OH), comprised a NOx adsorber, heat exchanger and a demister. These components were connected to the engine, and data were gathered to show both the adsorption of NOx from the engine, and desorption of NOx from the carbon-based sorbent material back into the engine intake, using a heated air stream. In order to quantify the NOx adsorbtion/desorption characteristics of the sorbent material, a bench top adsorption system was constructed and instrumented with thermocouples and the system output was fed into a NOx analyzer. The temperature of this apparatus was controlled while gathering data on the characteristics of the sorbent material. These data were required for development of a system model. Preliminary data were gathered in 2005, and will continue in early 2006. To assess the economic benefits of the proposed SNR technology the WVU research team has been joined in the last quarter by Dr Richard Turton (WVU -Chemical Engineering), who is modeling, sizing and costing the major components. The tasks will address modeling and preliminary design of the heat exchanger, demister and NOx sorbent chamber suitable for a given engine. A simplified linear driving force model was developed to predict NOx adsorbtion into the sorbent material as cooled exhaust passes over fresh sorbent material. This aspect of the research will continue into 2006, and the benefits and challenges of SNR will be compared with those of competing systems, such as Selective Catalytic Reduction.. Chemical kinetic modeling using the CHEMKIN software package was extended in 2005 to the case of slightly rich burn with EGR. Simulations were performed at 10%, 20%, 30% and 40% of the intake air replaced with EGR. NOx decomposition efficiency was calculated at the point in v time where 98% of fuel was consumed, which is believed to be a conservative approach. The modeling data show that reductions of over 70% are possible using the "98% fuel burned" assumption. Both the CHEMKIN and experimental data will be used for the construction of a NOx decomposition model in FY2006. A study of possible system configurations commenced in 2005, and will be incorporated into the model. It was clear that the system could not be designed on a two phase adsorption/desorption assumption, but must account for four phases: cooling, adsorbing, heating, and desorbing. Exhaust gas appears to be the most suitable desorbing stream
Co-Chaperone Bag-1 Plays a Role in the Autophagy-Dependent Cell Survival through Beclin 1 Interaction
No full textExpression levels of the major mammalian autophagy regulator Beclin 1 and its interaction with Bcl-2 regulate the switch between autophagic cell survival and apoptotic cell death pathways. However, some of the regulators and the precise mechanisms of these processes still remain elusive. Bag-1 (Bcl-2 associated athanogene-1), a member of BAG family proteins, is a multifunctional pro-survival molecule that possesses critical functions in vital cellular pathways. Herein, we report the role of Bag-1 on Bcl-2/Beclin 1 crosstalk through indirectly interacting with Beclin 1. Pull-down experiments suggested a molecular interaction between Bag-1 and Beclin 1 in breast cancer cell lines. On the other hand, in vitro binding assays showed that Bag-1/Beclin 1 interaction does not occur directly but occurs through a mediator molecule. Bag-1 interaction with p-Beclin 1 (T119), indicator of early autophagy, is increased during nutrient starvation suggesting involvement of Bag-1 in the autophagic regulation. Furthermore, CRISPR/Cas9-mediated Bag-1 knock-out in MCF-7 cells hampered cell survival and proliferation and resulted in decreased levels of total LC3 under starvation. Collectively, we suggest that Bag-1 modulates cell survival/death decision through maintaining macroautophagy as a component of Beclin 1-associated complexes
