京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20997号 / 医博第4343号 / 新制||医||1027(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 鈴木 実, 教授 平井 豊博, 教授 伊達 洋至 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Purpose: The purpose of this study is to investigate whether, in the context of making a go/no-go decision regarding a failing new product, the use of a stopping rule and/or a new decision-maker would reduce the escalation of commitment (EOC). Design/methodology/approach: This study uses a classroom experiment design and uses logistic regression and a chi-square test to analyze its data. Findings: The findings show that both responsible and non-responsible participants are more likely to perceive the negative performance of a new product as less negative and believe that the goal for the product can be reached when there is a stopping rule and proximal negative feedback indicates a level of performance below but very close to it than when there is no stopping rule. Therefore, they are more likely to continue the failing new product, whether they are responsible for the product or not. However, non-responsible decision-makers are more likely than their responsible counterparts to discontinue the failing new product in the absence of a stopping rule. Research limitations/implications: This paper extends the theory of EOC by showing that the use of a stopping rule and/or a new decision-maker may not reduce EOC. Practical implications: This paper provides useful guidelines for managers on how to reduce EOC. Originality/value: The originality and value of this paper are found in the investigation of a situation in which the use of a stopping rule and/or a new decision-maker may not reduce the EOC.

This paper aims to answer the question Why do some ceasefires de-escalate conflict better than others? By applying a theory-driven empirical comparative approach, a theoretical argument focused on compliance provisions is presented. The argument holds that more comprehensive compliance provisions in ceasefire agreements are more likely to de-escalate conflict than limited ones. The causal mechanism argues that more comprehensive compliance provisions will increase transparency and raise costs for non-compliance. This will result in an increase of trust between conflict parties, leading to greater de-escalation. The thesis studies two ceasefires, one in Colombia from 2017, and one in Nicaragua from 1990. Through a structured focused comparison, the study finds that the Nicaraguan ceasefire, which has more comprehensive compliance provisions, de-escalated violence more compared to the Colombian case, which has limited compliance provisions. Therefore, the study finds support for the hypothesis with the caveat that compliance provisions do not appear to influence agreement resilience for long-term goals in the agreements.

No description available.

Using a tailored dose distribution for personalized radiotherapy with the help of positron emission tomography (PET) might give an edge for successful tumour elimination. One of the main determinants for tumour radioresistance in several solid tumours has been investigated as hypoxia, including head and neck cancer (HNC). Using novel methods of converting radiotracer uptake into partial oxygen pressure distribution in the form of partial pressure maps, it is possible to delineate the hypoxic region of a target to further escalate the treatment dose there, aiming at an increase in tumour control. However, the registration between functional and structural images may have an impact on the effectiveness of dose escalation, and choosing the correct registration method could be imperative. In this master’s thesis, the impact of choosing rigid or deformable image registration between planning-CT and PET/CT images on the characterization of the hypoxic compartment, as well as on the treatment evaluation in terms of tumour control and normal tissue complication, was assessed. This was achieved by, using hypoxic patients of a cohort of 22 HNC patients, creating a separate plan for each registration method, for each patient, and comparing them quantitatively. The results showed that both methods would yield distinctly different dose distributions when planned using the same objectives and constraints in terms of dose level and shape. Furthermore, they both give a distribution of similar quality. However, using rigid registration together with the deformed PET did not render lower results overall in tumour control. Thus, no advantage could be seen in choosing deformable registration over rigid registration when aiming at tumour control.

Esta tese trata de crédito, não da análise dos demonstrativos financeiros, e sim a partir do momento em que o resultado de uma análise criteriosa e competente é colocada à disposição do comitê para decidir pela concessão ou não do crédito. A decisão de crédito é nosso enfoque principal. A tese está dividida em quatro partes. Na primeira parte fazemos uma revisão bibliográfica sobre crédito, dos fundamentos históricos à aplicação de modelos sofisticados de administração de carteiras (o Creditmetrics), passando pelo Estado da Arte das técnicas de credit scoring. A segunda parte trata dos fundamentos da teoria da análise da decisão, onde discutimos e analisamos o comportamento político e racional nas organizações, e os principais problemas decorrentes de atitudes indesejáveis como escalation, groupthink e bandwagon. A terceira parte discorre, inicialmente, sobre a pesquisa e sua metodologia, apresentando as hipóteses a serem testadas. Na seqüência, com base em dezoito entrevistas com diretores das principais entidades bancárias do país, descrevemos o processo geral para a concessão de crédito para grandes corporações e analisamos sete casos de concessões de crédito malsucedidas. Finalmente, com uma amostra de 54 bancos, realizamos a análise estatística dos resultados buscando comprovar nossas hipóteses de pesquisa. Na quarta e última parte apresentamos o sumário e conclusões da tese. Podemos destacar a relevância dos aspectos comportamentais, como fundamento da tomada de decisão e crédito: os testes realizados comprovam a influência do comportamento racional como redutor do índice de inadimplência; enquanto os sintomas de comportamento político, escalation e groupthink contribuem para o aumento do índice de inadimplência. / This thesis is concerned with credit decision and not with financial statements analysis. More specifically, it is focused on the decision making process of the credit committee once the results of a competent anlysis is avalaible. The thesis is divided in four parts. In the first we present a review about credit, from its historical developments up to the applications of sophisticated portfolio management models and other modern techniques. The second part deals with the fundamentals of decision theory. We discuss ans analyze political and rational decision behaviors within organizations, and phenomenon such as escalation, groupthink and bandwagon. The third part presents, initially, the research problem, its methodology and the hypothesis to be tested. Subsequently, based on eighteen interviews with bank executives in Brazil, we describe the decision processes employed in the concession of credits to large corporations. We also analyze seven cases of unsuccessful credit decisions. Finally we present the statistical analysis of a survey by questionnaires from 54 Brazilian banks. In the fourth and last part we present the conclusions of this thesis. The key results in the importance of behavioral aspects in the credit decision processes: the statistical tests confirm that the rational behavior mitigates the bankruptcy index; while the political behavior, escalation and groupthink contribute to an increment of the banruptcy index.

Background Due to technological and medical advances, increasing numbers of pregnant and post natal women require higher levels of care, including maternity high dependency care (MHDC). Up to 5% of women in the UK will receive MHDC, although there are varying opinions as to the defining features and definition of this care. Furthermore, limited evidence suggests that the size and type of obstetric unit (OU) influences the way MHDC is provided. There is robust evidence indicating that healthcare professionals must be able to recognise when higher levels of care are required and escalate care appropriately. However, there is limited evidence examining the factors that influence a midwife to decide whether MHDC is provided or a woman’s care is escalated away from the OU to a specialist unit. Research Aims 1. To obtain a professional consensus regarding the defining features of and definition for MHDC in OUs remote from tertiary referral units. 2. To examine the factors that influence a midwife to provide MHDC or request the escalation of care (EoC) away from the OU. Methods An exploratory sequential mixed methods design was used: Delphi survey: A three-round modified Delphi survey of 193 obstetricians, anaesthetists, and midwives across seven OUs (annual birth rates 1500-4500) remote from a tertiary referral centre in Southern England. Round 1 (qualitative) involved completion of a self-report questionnaire. Rounds 2/3 (quantitative); respondents rated their level of agreement or disagreement against five point Likert items for a series of statements. First round data were analysed using qualitative description. The level of consensus for the combined percentage of strongly agree / agree statements was set at 80% for the second and third rounds Focus Groups: Focus groups with midwives across three OUs in Southern England (annual birth rates 1700, 4000 and 5000). Three scenarios in the form of video vignettes were used as triggers for the focus groups. Scenario 1; severe pre-eclampsia, physiologically unstable 2; major postpartum haemorrhage requiring invasive monitoring 3; recent admission with chest pain receiving facial oxygen and continuous ECG monitoring. Two focus groups were conducted in each of the OUs with band 6 / 7 midwives. Data were analysed using a qualitative framework approach. Findings Delphi survey: Response rates for the first, second and third rounds were 44% (n=85), 87% (n=74/85) and 90.5% (n= 67/74) respectively. Four themes were identified (conditions, vigilance, interventions, and service delivery). The respondents achieved consensus regarding the defining features of MHDC with the exceptions of post-operative care and post natal epidural anaesthesia. A definition for MHDC was agreed, although it reflected local variations in service delivery. MHDC was equated with level 2 care (ICS, 2009) although respondents from the three smallest OUs agreed it also comprised level 1 care. The smaller OUs were less likely to provide MHDC and had a more liberal policy of transferring women to intensive care. Midwives in the smaller OUs were more likely to escalate care to ICU than doctors. Focus Groups: Factors influencing midwives’ EoC decisions included local service delivery, patient specific / professional factors, and guidelines to a lesser extent. ‘Fixed’ factors the midwives had limited or no opportunity to change included the proximity of the labour ward to the ICU and the availability of specialist equipment. Midwives in the smallest OU did not have access to the facilities / equipment for MHDC provision and could not provide it. Midwives in the larger OUs provided MHDC but identified varying levels of competence and used ‘workarounds’ to facilitate care. A woman’s clinical complexity and potential for physiological deterioration were influential as to whether MHDC was assessed as appropriate. Midwifery staffing levels, skill mix and workload (variable factors) could also be influential. Differences of opinion were noted between midwives working in the same OUs and varying reliance was placed on clinical guidelines. Conclusion Whilst a consensus on the defining features of, and definition for MHDC has been obtained, the research corroborates previous evidence that local variations exist in MHDC provision. Given midwives from the larger OUs had variable opinions as to whether MHDC could be provided, there may be inequitable MHDC provision at a local level. Organisationally robust systems are required to promote safe, equitable MHDC care including MHDC education and training for midwives and precise EoC guidelines (so workarounds are minimised). The latter must take into consideration local service delivery and the ‘variable’ factors that influence midwives’ EoC decisions.

Esta tese trata de crédito, não da análise dos demonstrativos financeiros, e sim a partir do momento em que o resultado de uma análise criteriosa e competente é colocada à disposição do comitê para decidir pela concessão ou não do crédito. A decisão de crédito é nosso enfoque principal. A tese está dividida em quatro partes. Na primeira parte fazemos uma revisão bibliográfica sobre crédito, dos fundamentos históricos à aplicação de modelos sofisticados de administração de carteiras (o Creditmetrics), passando pelo Estado da Arte das técnicas de credit scoring. A segunda parte trata dos fundamentos da teoria da análise da decisão, onde discutimos e analisamos o comportamento político e racional nas organizações, e os principais problemas decorrentes de atitudes indesejáveis como escalation, groupthink e bandwagon. A terceira parte discorre, inicialmente, sobre a pesquisa e sua metodologia, apresentando as hipóteses a serem testadas. Na seqüência, com base em dezoito entrevistas com diretores das principais entidades bancárias do país, descrevemos o processo geral para a concessão de crédito para grandes corporações e analisamos sete casos de concessões de crédito malsucedidas. Finalmente, com uma amostra de 54 bancos, realizamos a análise estatística dos resultados buscando comprovar nossas hipóteses de pesquisa. Na quarta e última parte apresentamos o sumário e conclusões da tese. Podemos destacar a relevância dos aspectos comportamentais, como fundamento da tomada de decisão e crédito: os testes realizados comprovam a influência do comportamento racional como redutor do índice de inadimplência; enquanto os sintomas de comportamento político, escalation e groupthink contribuem para o aumento do índice de inadimplência. / This thesis is concerned with credit decision and not with financial statements analysis. More specifically, it is focused on the decision making process of the credit committee once the results of a competent anlysis is avalaible. The thesis is divided in four parts. In the first we present a review about credit, from its historical developments up to the applications of sophisticated portfolio management models and other modern techniques. The second part deals with the fundamentals of decision theory. We discuss ans analyze political and rational decision behaviors within organizations, and phenomenon such as escalation, groupthink and bandwagon. The third part presents, initially, the research problem, its methodology and the hypothesis to be tested. Subsequently, based on eighteen interviews with bank executives in Brazil, we describe the decision processes employed in the concession of credits to large corporations. We also analyze seven cases of unsuccessful credit decisions. Finally we present the statistical analysis of a survey by questionnaires from 54 Brazilian banks. In the fourth and last part we present the conclusions of this thesis. The key results in the importance of behavioral aspects in the credit decision processes: the statistical tests confirm that the rational behavior mitigates the bankruptcy index; while the political behavior, escalation and groupthink contribute to an increment of the banruptcy index.

Purpose: This dissertation focuses on establishment of pre-clinical methods facilitating the use of PET imaging for selective sub-volume dose escalation. Specifically the problems addressed are 1.) The difficulties associated with comparing multiple PET images, 2.) The need for further validation of novel PET tracers before their implementation in dose escalation schema and 3.) The lack of concrete pre-clinical data supporting the use of PET images for guidance of selective sub-volume dose escalations. Methods and materials: In order to compare multiple PET images the confounding effects of mispositioning and anatomical change between imaging sessions needed to be alleviated. To mitigate the effects of these sources of error, deformable image registration was employed. A deformable registration algorithm was selected and the registration error was evaluated via the introduction of external fiducials to the tumor. Once a method for image registration was established, a procedure for validating the use of novel PET tracers with FDG was developed. Nude mice were used to perform in-vivo comparisons of the spatial distributions of two PET tracers, FDG and FLT. The spatial distributions were also compared across two separate tumor lines to determine the effects of tumor morphology on spatial distribution. Finally, the research establishes a method for acquiring pre-clinical data supporting the use of PET for image-guidance in selective dose escalation. Nude mice were imaged using only FDG PET/CT and the resulting images were used to plan PET-guided dose escalations to a 5 mm sub-volume within the tumor that contained the highest PET tracer uptake. These plans were then delivered using the Small Animal Radiation Research Platform (SARRP) and the efficacy of the PET-guided plans was observed. Results and Conclusions: The analysis of deformable registration algorithms revealed that the BRAINSFit B-spline deformable registration algorithm available in SLICER3D was capable of registering small animal PET/CT data sets in less than 5 minutes with an average registration error of .3 mm. The methods used in chapter 3 allowed for the comparison of the spatial distributions of multiple PET tracers imaged at different times. A comparison of FDG and FLT showed that both are positively correlated but that tumor morphology does significantly affect the correlation between the two tracers. An overlap analysis of the high intensity PET regions of FDG and FLT showed that FLT offers additional spatial information to that seen with FDG. In chapter 4 the SARRP allowed for the delivery of planned PET-guided selective dose escalations to a pre-clinical tumor model. This will facilitate future research validating the use of PET for clinical selective dose escalation.

Abstract In the summer of 2009, Tampa General care providers met with Hospital Administration to express concern that violence on care units was a growing problem and making it difficult to provide quality care. Nurses stated that such violence was one important reason many of their peers choose to retire. Administration took this situation seriously and formed a committee to gather information and submit suggestions to reduce the violence. The committee consisted of representatives from several nursing units, human resources, risk management, security, and administration. Duties assigned included investigation of the actual number of reports on all units and trends. The committee was also charged with the production of a report regarding reviewing other hospital data, literature review, and developing recommendations. Internal reports indicated that the total prevalence of reported violence as well as the incidence per patient had increased annually since 2005. The hospital reports contradicted the national literature regarding the emergency department (ED) and psychiatric unit (Psych) being the two hospital units with the highest number of violent events. One possible reason for the difference is that these departments require all care providers to attend de-escalation and self-defense classes annually. Based on these findings, the researcher developed and adapted training similar to that of the ED for other units reporting aggressive, abusive, and violent patients. The committee approved a draft plan for implementation. Following presentation to Nursing Administration, some modifications were made, and the Internal Review Boards of the hospital and University of South Florida (USF) approved the project. The hypothesis tested in this study was whether training in de-escalation and self-defense modifies providers' behaviors to prevent or reduce aggressive, abusive, or violent behavior by patients and visitors. The independent variable was training. The dependent variable was requests for assistance with unruly, angry, or violent patients or visitors. Event reports of the year prior were used for historical comparison. Event reports for the experimental period were assembled subsequent to the training for comparison. Nursing Administration selected two units to receive the training intervention. The two units selected were neither the worst nor the best in numbers, but rather the middle. Nursing required that all training be scheduled in normal department meetings and that Nurse Managers of the units agree to participate. The research design presumed that at least 85% of care providers on a unit would attend the training. Schedules were developed to accommodate all care providers. The training was presented during June of 2010. Experimental and comparison units were monitored each month for the number of reported violent events (Code Grays) on each unit. During the fourth months of monitoring, there was a data spike in the Cardiac Care unit. No action was taken until another spike occurred during the sixth month. It was determined that an error had occurred that partially invalidated the data from the Cardiac Care unit: the 85% participation rate among staff had not been reached. Monitoring continued for 12 months after the training. The Eldercare unit showed reduced requests for assistance. Overall, the Cardiac Care unit increased requests for assistance from the year before. Results were adjusted for patient census. Wilcoxon Signed Ranks Testing was performed and displayed using box plots to show how far the median changed during the research from one group to the next. The analysis compared prior year with the year following the interventions, and indicated that there was a movement toward a reduction of Code Grays. To determine if there was a difference between comparison units and experimental units 12 months after the training, Poisson Regression Analysis was utilized. When the comparison units were set as the reference, Poisson analysis indicated the events were decreasing on both units. The Cardiac Care unit did not have a statistically significant p value. The Eldercare unit had a p value of .019. In conclusion, the results are mixed and statistically inconclusive. From the care providers' perspective, any reduction in violence is significant. The data regarding the training interventions indicates that there was an empirical, albeit not a statistically significant, change in Code Gray reports. Training may have reduced the violence on the Eldercare unit by nearly half.