Macro and Micro Dynamics of City Size Distributions: The Case of Israel

We study the distribution of sizes in the Israeli system of cities, using a rank-size representation of population distributions from 1950 to 2005. Based on a multiplicative model of proportionate growth, we develop a quantitative comparison relating the change in the rank-size curves to the change in the real data of Israeli cities during this period. At the level of macro dynamics, there is good agreement between the model and the real data. At the micro level, however, the model is less successful as the mean variation of the cities’ rank during the period studied is much larger in the model than in the real data. To illustrate this difference, we use the rankclock representation

Analyzing the health care cost curve: a case study.

This case study uses data from a self-insured employer plan to perform an analysis into the properties of the health care cost curve. The analysis shows that one statistical property of the health care cost curve is that costs rise continuously, not on an annual or monthly basis. Graphical analysis indicates that managed care techniques used to restrain costs can also smooth utilization, producing the continuously growing cost curve observed. The analysis further illustrates that there is no one cost curve -analysis must be segmented by population. Finally, the power of predictive models to fit the cost curve varies by population. To the extent that these results generalize to other health plans, this analysis should be used to inform the implementation of strategies to bend the cost curve. Population health management programs and health policy should be based on continuous analysis and adaption rather than implemented as one-off changes

Appendix: Expand Wikipedia stub on supplier - induced demand

Appendix for article that has been accepted for Journal of Economic Education. Abstract for article: The authors describe a Wikipedia-based project designed for a graduate course introducing health economics to experienced healthcare professionals. The project allows such students to successfully write articles on niche topics in rapidly evolving health economics subspecialties. These students are given the opportunity to publish their completed projects in Wikipedia. Despite the lack of conventional classroom incentives, the authors have found that the students generally choose to enter their final projects intoWikipedia. The authors explore the motivators for this behavior from the perspective of human capital development and reflect on the implications for enhancing economics education. Finally, they comment more generally on the value of assignments within graduate education that allow adult students to determine their degree of effort and reward along the intensive margin. Keywords: economics education, human capital, supplier-induced demand, Wikipedi

Extending political participation in China: new opportunities for citizens in the policy process

Authoritarian political systems are portrayed as offering few opportunities for citizens to participate in politics – particularly in the policy process. This paper’s contribution is to set out new mechanisms that enable Authoritarian political systems are portrayed as offering few opportunities for citizens to participate in politics – particularly in the policy process. This paper’s contribution is to set out new mechanisms that enable Chinese citizens to evaluate government performance, contribute to decision-making, shape policy agendas and feed back on implementation. Based on fieldwork in the city of Hangzhou, we argue that the local party-state orchestrates citizen participation in the policy process, but members of the public nevertheless do have influence. Political participation is widening in China, but it is still controlled. It is not yet clearly part of a process of democratization, but it does establish the principle of citizen rights to oversee the government

Susceptibility to ATP depletion of primary proximal tubular cell cultures derived from mice lacking either the alpha1 or the alpha2 isoform of the catalytic domain of AMPK.

International audienceBACKGROUND: The purpose of this study was to determine whether AMPK influences the survival of primary cultures of mouse proximal tubular (MPT) cells subjected to metabolic stress. Previous studies, using an immortalized MPT cell line, suggest that AMPK is activated during metabolic stress, and ameliorates stress-induced apoptosis of these cells. METHODS: Primary MPT cells were cultured from AMPK knockout (KO) mice lacking either the alpha1 or the alpha2 isoform of the catalytic domain of AMPK. MPT cells were subjected to ATP depletion using antimycin A. RESULTS: Surprisingly, there was no difference in the amount of death induced by metabolic stress of MPT cells from either type of AMPK KO mice compared to its WT control. Moreover, inhibition of the activity of the alpha1 isoform in primary MPT cells from alpha2-/- mice (pharmacologically, via compound C) or inhibition of the alpha2 isoform in primary MPT cells from alpha1-/- mice (molecularly, via knockdown) both decreased cell viability equivalently in response to metabolic stress. The explanation for this unexpected result appears to be an adaptive increase in expression of the non-deleted alphaisoform. As a consequence, total As a consequence-domain expression (i.e. alpha1 + alpha2), is comparable in kidney cortex and in cultured MPT cells derived from either type of KO mouse versus its WT control. Importantly, each alphaisoform appears able to compensate fully for the absence of the other, with respect to both the phosphorylation of downstream targets of AMPK and the amelioration of stress-induced cell death. CONCLUSIONS: These findings not only confirm the importance of AMPK as a pro-survival kinase in MPT cells during metabolic stress, but also show, for the first time, that each of the two alpha-isoforms can substitute for the other in MPT cells from AMPK KO mice with regard to amelioration of stress-induced loss of cell viability

The impact of Achilles tendon pathology on lower limb joint stiffness regulation during hopping tasks

Achilles tendinopathy (AT) is a debilitating running injury affecting 50% of distance runners over their lifetime. Ultrasound (US) imaging studies have shown that pathological changes are present in 11-52% of asymptomatic individuals. Impairments of the lower leg muscle-tendon function may develop with AT however alteration of lower limb loading strategies has not been examined in runners with asymptomatic Achilles tendon pathology. The primary aim of the thesis was to determine if Achilles tendon pathology changes lower limb loading patterns. It was hypothesised that there would be a different loading pattern between the ankle and knee in runners with Achilles tendon pathology. In order to investigate this primary aim, secondary aims were developed to determine the prevalence of Achilles tendon pathology in an asymptomatic running population and to determine any associated factors of tendon pathology. This study initially assessed the prevalence of tendon pathology and a number of associated risk factors for 37 experienced, high mileage male endurance runners with no history of Achilles tendon pain. The tendon was assessed using US by a musculoskeletal radiologist and classified as either normal or abnormal. Height, body mass, waist circumference, and weight bearing ankle dorsiflexion range of motion (ROM) with the knee in a flexed and extended position were measured. A survey quantified the running history of participants. Following the initial study, 14 runners with no history of Achilles tendon pain and a normal Achilles tendon on US imaging, and 12 runners with asymptomatic Achilles tendon pathology were assessed in a series of further studies. A third group of 12 runners with symptomatic AT were also studied. Each runner completed single leg hopping for both limbs on a level and inclined surface. Embedded in the surface was a force plate (1000Hz) that was synchronised with a three dimensional motion capture system (250Hz). Nonparametric statistics were used to examine the effect of surface angle and group on hopping biomechanics. All results are reported as median and interquartile range (IQR). Almost half (46%) of the asymptomatic distance runners had at least one abnormal tendon. The runners with asymptomatic Achilles tendon pathology had significantly more years of running history (Median 20.0 years, IQR 6.0-25.5, p=0.024) than the runners with no pathology on US (Median 7.0 years, IQR 5.0-15.0). No significant differences between the groups was identified for age, height, mass, waist circumference, ankle ROM, number of weekly running sessions, weekly mileage and number of long distance (marathon and half marathon) running events completed in their lifetime. Symptomatic runners had significantly less active ankle joint stiffness (Level – Median = 8.2 Nm/kg/rad, IQR = 7.7-9.2; Incline - Median= 8.1 Nm/kg/rad, IQR = 7.2-9.7) when compared to the normal group (Level – Median = 9.8 Nm/kg/rad, IQR = 9.0-10.5; Incline - Median= 10.2 Nm/kg/rad, IQR = 8.7-10.4) for both the level (p=0.044) and inclined (p=0.042) surfaces. No differences were identified for leg stiffness between the three groups. Asymptomatic male distance runners had a high incidence of tendon pathology compared to other populations (e.g. soccer players) and cumulative load in running years is an associated factor of tendon change. This thesis identified that the presence of Achilles tendon pathology without a history or presence of pain did not alter lower limb loading strategies. However, runners with symptomatic AT had reduced ankle stiffness. This may explain the recalcitrant and recurrent nature of AT if runners are not able to increase their ankle stiffness following rehabilitation and recovery after injury

Bioengineering and biomechanical approaches for pancreatic cancer

Pancreatic cancer is the fourth-leading cause of cancer related mortality and is predicted to be the second leading cause of cancer death by 2030. A hallmark feature of pancreatic ductal adenocarcinoma (PDAC) is dense fibrotic stroma surrounding the tumor, composed of extracellular matrix (ECM) and cells such as myofibroblasts. The properties of this stroma and functional contribution to carcinogenesis and disease progression has been the subject of intense focus in the past decade; yet, the role of mechanobiology in modulating the phenotype of immune cells in the tumor microenvironment remains to be elucidated. Although a lack of understanding PDAC etiology and progression limits effective treatments that can be deployed by clinicians, current methods of diagnosing PDAC likely are insufficient even if such treatments exist, especially if there is a narrow early window for drug efficacy. Recently, however, extracellular vesicles have emerged as powerful circulating blood biomarkers, thus paving the way for a new era of non-invasive cancer diagnostics. However, currently the process of extracellular vesicle isolation and detection is not only highly inefficient, but also technically challenging. This thesis describes bioengineering tools and biomechanical investigations of pancreatic cancer. In Chapter 2, the biomechanical phenotype of macrophages is studied in context of a stromal modulation agent, the chemotherapeutic drug tamoxifen. Tamoxifen was found to regulate macrophage focal adhesion dynamics, cytoskeletal activity, migratory behavior, and expression of TLR4. In Chapter 3, a novel microfluidic device was modeled and built to determine cell adhesion strength with potential applications to investigate regulation of focal adhesion structure by candidate drugs. Chapter 4 describes the development of methods and devices for isolation and detection of extracellular vesicles using acoustophoresis and a graphene field effect transistor, respectively. Such tools and perspectives could serve to detect PDAC earlier as well as identify and test new therapies.Open Acces

The Impact of Medical Spending Growth on Guaranteed Renewable Health insurance

I examine the problem of writing guaranteed renewable health insurance in the presence of medical spending growth. Prior research suggests that the growth and difficulty in forecasting future medical costs is an impediment to multiperiod health insurance, where contract reserves are used to pay a portion of the benefits in later years of the contract. Medical spending growth is an input to calculating the magnitude of premiums and reserves, so setting up reserves to pay future claims involves forecasting spending growth. Hedging assets can ameliorate the investment problem by providing assets that automatically adjust to unexpected shocks in spending growth. I expand an existing model of guaranteed renewability in an economy with risk to show the specific ways that medical spending growth enters the premium and reserve functions. I treat stochastic trend as a factor the insurance company can predict with error. I utilize aggregate and individual level insurance spending data and financial returns data to analyze whether medical trend can be hedged with existing assets. I separate trend into predictable and error components and analyze the correlation between the error component and return on assets. I find that medical spending growth is predictable with error over short and medium time horizons. I find that there is no significant correlation between asset returns and forecast errors across several broad asset classes. The combination of partially predictable spending growth and the absence of a hedging asset imply that insurers should be using reserves to manage the macroeconomic risk of spending growth. The load for reserving for trend is an up-front cost in addition to the up-front expense of guaranteed renewability. Insurers should use a diversified investment strategy for reserves rather than one targeted at trying to match spending growth. I conclude by noting the positive and negative effects of the newly passed health reform law (PPACA) on guaranteed renewable health insurance and other health insurance arrangements that require contract reserves and policies that shift health care spending onto public plans

Perspectives on Peer Support for Tenure-track Librarians: The Annual “Juniors’” Retreat at Stony Brook University

The non-tenured faculty at Stony Brook University Libraries has implemented an annual one-day retreat which includes presentations, posters of research in progress, group activities, and a discussion of current library issues. The retreats have inspired junior faculty members and assisted them in forming a supportive network of peer mentoring for guidance through the tenure process