The Obesity of Economics: An Application of the Law of Demand to Obesity Prevalence within the United States

We estimate the demand function for obesity using a panel model across fifty-one U.S. states over the years 2000 to 2010. We study the impact of educational attainment, average commute time to work, relative price, per capita income, and the state unemployment rate on obesity levels, controlling for differences in regional culture. We find that since 2001, obesity is a function of the relative prices of healthy and non-healthy foods across regions, as well as state per capita income and educational attainment. From 2005 to 2010, we find that average commute time to work is a significant factor in the state obesity rate as well. Our results indicate that obesity is an inferior good due to its negative relationship with per capita income. In addition, we find obesity to be very inelastic to changes in the relative price of healthy and non-healthy food over both time periods. For every one percentage increase in the relative price of healthy food, the obesity rate increased by only 0.062 percent. Our findings suggest that in order to most effectively reduce the state obesity rate, public policies should focus on increasing educational attainment rather than lowering the relative price of healthy food. We find regional culture to be the largest indicator of state obesity rate. This suggests that, regardless of the price of food, some people will choose to adopt an unhealthy lifestyle as a result of cultural influence

Person to Person in New Zealand

While still in the midst of their study abroad experiences, students at Linfield College write reflective essays. Their essays address issues of cultural similarity and difference, compare lifestyles, mores, norms, and habits between their host countries and home, and examine changes in perceptions about their host countries and the United States. In this essay, Katie Hasenoehri describes her observations during her study abroad program at the University of Canterbury in Christchurch, New Zealand

Doctor of Philosophy

dissertationIn the past few decades, a revolution in our understanding of brain function has occurred based on demonstrations that astrocytes play critical roles in synaptic physiology. These findings led to the concept of the "tripartite synapse," which redefines the synapse to be comprised of not only the pre- and postsynaptic neuronal elements, but also the astrocyte processes that interact with them. Likewise, temporal lobe epilepsy (TLE) is a seizure disorder that affects the structure and function of networks of both neurons and astrocytes. One of the hallmark findings in TLE is the profound change in astrocyte structure and gene expression, a process called astrogliosis, throughout the brain regions involved in seizure generation. Using a well-established rat model of TLE, our lab recently demonstrated that astrocytes begin to express kainate receptor subunits during the development of TLE, and this increased expression persists throughout chronic epilepsy, suggesting that this pathway may play a role in the development of hyperexcitable circuits. However, the functional consequences of changes in reactive astrocytes and their impact on tripartite synapse function are not known. To facilitate imaging experiments at the tripartite synapse, I developed a novel genetic tool that uses a fluorescent reporter system to label astrocytes with tdTomato and neurons with Cerulean. This plasmid also includes the genetically encoded calcium-indicating protein, Lck-GCaMP6f, enabling the monitoring of calcium transients in the fine processes of all transfected cells. I expressed this novel tool in the rat brain with in utero electroporation and characterized expression throughout development using immunohistochemistry for markers of astrocytes and neurons. I demonstrated the utility of this tool to investigate functional subcellular Ca2+ signals in both astrocytes and neurons. This tool was used in experiments that showed that Ca2+ signaling is altered during the development of temporal lobe epilepsy in the rat kainic acid-induced model of status epilepticus. Spontaneous Ca2+ events in the processes of reactive astrocytes exhibited longer interevent intervals and longer duration of events compared to astrocytes from healthy tissue. I also found that increased protein expression of kainate receptors translated to functional expression of kainate receptors on a subset of reactive astrocytes following kainic acid-induced SE, suggesting a pathway that may be involved in pathological neuron-glial signaling contributing to the development of epilepsy. Taken together, these results indicate that alterations in Ca2+ signaling in astrocytes during the development of TLE may have important consequences on function at the tripartite synapse. This dissertation lays the groundwork for future studies in the tripartite synapse and points to a novel pathway that may be involved in pathological neuron-astrocyte signaling that contributes to hyperexcitability during epileptogenesis

Biomechanical analysis of body movements of myoelectric prosthesis users during standardized clinical tests

Objective: The objective clinical evaluation of user's capabilities to handle their prosthesis is done using various tests which primarily focus on the task completion speed and do not explicitly account for the potential presence of compensatory motions. Given that the excessive body compensation is a common indicator of inadequate prosthesis control, tests which include subjective observations on the quality of performed motions have been introduced. However, these metrics are then influenced by the examiner's opinions, skills, and training making them harder to standardize across patient pools and compare across different prosthetic technologies. Here we aim to objectively quantify the severity of body compensations present in myoelectric prosthetic hand users and evaluate the extent to which traditional objective clinical scores are still able to capture them. Methods: We have instructed 9 below-elbow prosthesis users and 9 able-bodied participants to complete three established objective clinical tests: Box-and-Blocks-Test, Clothespin-Relocation-Test, and Southampton-Hand-Assessment-Procedure. During all tests, upper-body kinematics has been recorded. Results: While the analysis showed that there are some correlations between the achieved clinical scores and the individual body segment travel distances and average speeds, there were only weak correlations between the clinical scores and the observed ranges of motion. At the same time, the compensations were observed in all prosthesis users and, for the most part, they were substantial across the tests. Conclusion: The sole reliance on the currently available objective clinical assessment methods seems inadequate as the compensatory movements are prominent in prosthesis users and yet not sufficiently accounted for

Occupational physical activity: the good, the bad, and the proinflammatory

BackgroundPhysical activity (PA) is beneficial for preventing several conditions associated with underlying chronic inflammation, e. g., cardiovascular disease (CVD) and cancer. While an active lifestyle appears to have anti-inflammatory effects, high levels of occupational PA (OPA) were associated with inflammation and elevated mortality risks. We aimed to summarize the current knowledge (1) on the association between inflammation and OPA and (2) its implications for health and mortality.Methods and resultsThis mini-review summarized relevant literature published before January 2023 using established scientific databases and sources. For the primary outcome, observational studies (S) reporting immunological effects (O) in subjects (P), with high (I) vs. low OPA (C), were included. For secondary outcomes, i.e., morbidity and mortality associated with inflammatory processes, (systematic) reviews were included. While “active” occupations and “moderate” OPA appear to have beneficial effects, low (particularly sedentary) and “high-intensity” OPA (particularly including heavy lifting tasks) were associated with inflammation and (CVD and cancer-related) mortality; higher leisure-time PA has been almost consistently associated with lower proinflammatory markers and all-cause mortality risks. Workplace interventions appear to counter some of the observed health effects of unfavorable work strain.ConclusionThe few studies addressing OPA “intensity” and inflammatory markers are largely heterogeneous regarding OPA classification and confounder control. Sedentary and “heavy” OPA appear to promote proinflammatory effects. In addition to targeted management of work-related physical strain and hazardous environmental co-factors, occupational health providers should focus on employer-initiated exercise interventions and the promotion of leisure-time PA

The long-term effects of an implantable drop foot stimulator on gait in hemiparetic patients

Drop foot is a frequent abnormality in gait after central nervous system lesions. Different treatment strategies are available to functionally restore dorsal extension during swing phase in gait. Orthoses as well as surface and implantable devices for electrical stimulation of the peroneal nerve may be used in patients who do not regain good dorsal extension. While several studies investigated the effects of implanted systems on walking speed and gait endurance, only a few studies have focussed on the system’s impact on kinematics and long-term outcomes. Therefore, our aim was to further investigate the effects of the implanted system ActiGait on gait kinematics and spatiotemporal parameters for the first time with a 1-year follow-up period. 10 patients were implanted with an ActiGait stimulator, with 8 patients completing baseline and follow-up assessments. Assessments included a 10-m walking test, video-based gait analysis and a Visual Analogue Scale (VAS) for health status. At baseline, gait analysis was performed without any assistive device as well as with surface electrical stimulation. At follow-up patients walked with the ActiGait system switched off and on. The maximum dorsal extension of the ankle at initial contact increased significantly between baseline without stimulation and follow-up with ActiGait (p = 0.018). While the spatio-temporal parameters did not seem to change much with the use of ActiGait in convenient walking speed, patients did walk faster when using surface stimulation or ActiGait compared to no stimulation at the 10-m walking test at their fastest possible walking speed. Patients rated their health better at the 1-year follow-up. In summary, a global improvement in gait kinematics compared to no stimulation was observed and the long-term safety of the device could be confirmed

Translating Research on Myoelectric Control into Clinics-Are the Performance Assessment Methods Adequate?

Missing an upper limb dramatically impairs daily-life activities. Significant efforts in overcoming the issues arising from this disability have been made in both academia and industry, although their clinical outcome is still limited. Translation of prosthetic research into clinics has been challenging because of the difficulties in meeting the necessary requirements of the market. In this perspective, we focus on myocontrol algorithms for upper limb prostheses and we emphasize that one relevant factor determining the relatively small clinical impact of these methods is the limit of commonly used laboratory performance metrics. The laboratory conditions, in which the majority of the solutions are being evaluated, fail to sufficiently replicate real-life challenges. We qualitatively substantiate this argument with data from seven transradial amputees. Their ability to control a myoelectric prosthesis was tested by measuring the accuracy of offline EMG signal classification, as a typical laboratory performance metrics, as well as by clinical scores when performing standard tests of daily living. Despite all subjects reached relatively high classification accuracy offline, their clinical scores were largely different and were not strongly predicted by classification accuracy. As argued in previous reports, we reinforce the suggestion to test myocontrol systems using clinical tests on amputees, fully fitted with sockets and prostheses highly resembling the systems they would use in daily living, as evaluation benchmark. Agreement on this level of testing for systems developed in research laboratories would facilitate clinically relevant progresses in this field.<br

Antenatal magnetic resonance imaging versus ultrasound for predicting neonatal macrosomia: a systematic review and meta-analysis

BACKGROUND: Fetal macrosomia is associated with an increased risk of adverse maternal and neonatal outcomes. OBJECTIVES: To compare the accuracy of antenatal two-dimensional (2D) ultrasound, three-dimensional (3D) ultrasound, and magnetic resonance imaging (MRI) in predicting fetal macrosomia at birth. SEARCH STRATEGY: Medline (1966-2013), Embase, the Cochrane Library and Web of Knowledge. SELECTION CRITERIA: Cohort or diagnostic accuracy studies of women with a singleton pregnancy, who had third-trimester imaging to predict macrosomia (>4000 g, >4500 g or >90th or >95th centile). DATA COLLECTION AND ANALYSIS: Two reviewers screened studies, performed data extraction and assessed methodological quality. The bivariate model was used to obtain summary sensitivities, specificities and likelihood ratios. MAIN RESULTS: Fifty-eight studies (34 367 pregnant women) were included. Most were poorly reported. Only one study assessed 3D ultrasound volumetry. For predicting birthweight >4000 g or >90th centile, the summary sensitivity for 2D ultrasound (Hadlock) estimated fetal weight (EFW) >90th centile or >4000 g (29 studies) was 0.56 (95% CI 0.49-0.61), 2D ultrasound abdominal circumference (AC) >35 cm (four studies) was 0.80 (95% confidence interval [95% CI] 0.69-0.87) and MRI EFW (three studies) was 0.93 (95% CI 0.76-0.98). The summary specificities were 0.92 (95% CI 0.90-0.94), 0.86 (95% CI 0.74-0.93) and 0.95 (95% CI 0.92-0.97), respectively. CONCLUSION: There is insufficient evidence to conclude that MRI EFW is more sensitive than 2D ultrasound AC (which is more sensitive than 2D EFW); although it was more specific. Further primary research is required before recommending MRI EFW for use in clinical practice