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The combustion of fossil fuels such as coal, natural gas, and oil is the primary source of energy to power our everyday lives. These energy sources are non-renewable and their continued consumption will only accelerate the already evident warming of the planet. One of the primary products of burning fossil fuels, carbon dioxide (fossil fuels are carbon-based fuels), has increased by 24% in the past 60 years which can be explained by the increased global energy demand and subsequent acceleration of fossil fuel consumption. It is unreasonable, though, to immediately stop our use of fossil fuels as an energy source without a viable replacement. Although it is 93 million miles away, the largest energy source available to humans is the sun. Nature has evolved to utilize the vast quantity of solar irradiation that illuminates the earth in order to perform complex photochemical reactions such as the biosynthesis of sugars. While there are researchers who are attempting to mimic the structure and function of these biological systems, the research discussed in this dissertation is focused on a more energy-relevant transformation: the conversion of solar energy into the simplest chemical fuel, hydrogen fuel. Transition metal complexes are capable of performing all the required steps needed to convert sunlight into hydrogen fuel: absorption of solar radiation, and catalytic orchestration of the combination of the two electrons and two protons required to form H2. While known technology exists for this conversion, the efficiency of all required steps are currently not at a level that makes the system economically/commercially viable. The work discussed herein is related to key steps in the path from solar energy to H2. The first chapter is focused on factors that influence the formation of a transition metal hydride complex, a key intermediate in catalytic hydrogen production. Chapter 2 then describes a model system in which to study hydride formation using two different methods is described, and Chapter 3 discusses systematic variation in structural parameters on the model system and how they influence hydride formation is then discussed. Finally, presented in Chapter 4 are efforts to improve the spectral absorbance of an existing class of chromophores, followed by efforts to directly form transition metal hydrides via light absorption in Chapter 5.

This paper juxtaposes the clinical management of two patients with intracranial hypertension secondary to viral infection: one due to Human Herpesvirus-6 and the second due to Varicella Zoster Virus. Our cases highlight the clinical and scientific importance of cerebrospinal fluid viral polymerase chain reaction testing in the evaluation of the high-pressure headache syndrome. Keywords: Headache, Meningitis, Pseudotumor, Intracranial, Hypertension, CSF, Infection, HHV-6

We report on spin dynamics of individual, localized neutral impurities immersed in a Bose-Einstein condensate. Single Cesium atoms are transported into a cloud of Rubidium atoms, thermalize with the bath, and the ensuing spin-exchange between localized impurities with quasi-spin $F_i=3$ and bath atoms with $F_b=1$ is resolved. Comparing our data to numerical simulations of spin dynamics we find that, for gas densities in the BEC regime, the dynamics is dominated by the condensed fraction of the cloud. We spatially resolve the density overlap of impurities and gas by the spin-population of impurities. Finally we trace the coherence of impurities prepared in a coherent superposition of internal states when coupled to a gas of different densities. For our choice of states we show that, despite high bath densities and thus fast thermalization rates, the impurity coherence is not affected by the bath, realizing a regime of sympathetic cooling while maintaining internal state coherence. Our work paves the way toward non-destructive probing of quantum many-body systems via localized impurities., 4 pages with 4 figures, 5 pages of appendix

INTRODUCTION Although the Child Hospital Consumer Assessment of Healthcare Providers and Systems is a validated tool for the inpatient experience, it may not address features unique to the pediatric emergency department (PED). There is currently no publicly available validated patient-reported experience survey for the PED, and what matters most in this setting remains unknown. METHODS Twelve semistructured interviews were conducted with a convenience sample of parents of children younger than 14 years at a Canadian PED. Data analysis was performed using inductive thematic analysis to identify aspects of patient-reported experiences that matter most to parents in the PED. RESULTS Five themes were identified: (1) making waiting a positive experience, (2) taking the time to provide care, (3) forging a positive partnership, (4) speak up for safe care, and (5) making the environment feel safer. Parents highlighted that while waiting for care is not desirable, it is made more acceptable through the communication of wait time estimates and the presence of child activities in the waiting room. Furthermore, although interactions with providers are brief, parents emphasized the importance of creating an environment of partnership with open communication, taking the time to examine their child, and actively demonstrating the provision of safe, quality care. CONCLUSIONS Results from this study suggest that a patient-reported experience survey in the PED may need to embed elements not currently captured in Child Hospital Consumer Assessment of Healthcare Providers and Systems, such as waiting room experience, comprehensiveness of health assessments, and observations of safety measures. Future studies can use these findings to develop a patient-reported experience survey for use in the PED.

We report on the experimental doping of a $^{87}$Rubidium (Rb) Bose-Einstein condensate (BEC) with individual neutral $^{133}$Cesium (Cs) atoms. We discuss the experimental tools and procedures to facilitate Cs-Rb interaction. First, we use degenerate Raman side-band cooling of the impurities to enhance the immersion efficiency for the impurity in the quantum gas. We identify the immersed fraction of Cs impurities from the thermalization of Cs atoms upon impinging on a BEC, where elastic collisions lead to a localization of Cs atoms in the Rb cloud. Second, further enhancement of the immersion probability is obtained by localizing the Cs atoms in a species-selective optical lattice and subsequent transport into the Rb cloud. Here, impurity-BEC interaction is monitored by position and time resolved three-body loss of Cs impurities immersed into the BEC. This combination of experimental methods allows for the controlled doping of a BEC with neutral impurity atoms, paving the way to impurity aided probing and coherent impurity-quantum bath interaction.

Background The objective of the present study was to evaluate the cost-utility of bariatric surgery in a lifetime horizon from a Swedish health care payer perspective. Methods A decision analytic model using the Markov process was developed covering cardiovascular diseases, type 2 diabetes, and surgical complications. Clinical effectiveness and safety were based on the literature and data from the Scandinavian Obesity Surgery Registry. Gastric bypass, sleeve gastrectomy, and gastric banding were included in the analysis. Cost data were obtained from Swedish sources. Results Bariatric surgery was cost saving in comparison with conservative management. It also led to a substantial reduction in lifetime risk of events: from a 16 % reduction in the risk of transient ischaemic attacks to a 62 % reduction in the incidence of type 2 diabetes. Over a lifetime, surgery led to savings of €8408 and generated an additional 0.8 years of life and 4.1 quality-adjusted life years (QALYs) per patient, which translates into gains of 32,390 quality-adjusted person-years and savings of €66 million for the cohort, operated in 2012. Analysis of the consequences of a 3-year delay in surgery provision showed that the overall lifetime cost of treatment may be increased in patients with diabetes or a body mass index >40 kg/m2. Delays in surgery may also lead to a loss of clinical benefits: up to 0.6 life years and 1.2 QALYs per patient over a lifetime. Conclusion Bariatric surgery, over a lifetime horizon, may lead to significant cost savings to health care systems in addition to the known clinical benefits. Electronic supplementary material The online version of this article (doi:10.1007/s11695-014-1567-5) contains supplementary material, which is available to authorized users.

An increasing cultural practice in soybean, Glycine max (L.), production is the use of winter annual cover crops before planting. Species of grasses, legumes, and forbs are planted for many agronomic purposes during the fall months. In the spring, cover crops are killed and soybean planted into the residue. When the termination of the cover crops is delayed for longer lasting benefits, insect pest issues can arise. The movement of insect pests from cover crops to subsequent cash crops happens through a connection known as the "Green Bridge". Pests found in cover crops such as the pea leaf weevil, Sitona lineatus L. (Coleoptera: Curculionidae), can be particularly damaging to immature soybean plants. Experiments were conducted to tests how cover crops influence insect populations in soybean. Also, various chemical control options, soybean planting populations, and the timing of cover crop termination prior to planting were tested in these cover crop-soybean systems. Lastly, an experiment was conducted to measure how various species of cover crops and neonicotinoid seed treatments affect arthropod diversity in soybean fields

Objective: To evaluate the cost-effectiveness of bariatric surgery in Italy from a third-party payer perspective over a medium-term (10 years) and a long-term (lifetime) horizon. Methods: A state-transition Markov model was developed, in which patients may experience surgery, post-surgery complications, diabetes mellitus type 2, cardiovascular diseases or die. Transition probabilities, costs, and utilities were obtained from the Italian and international literature. Three types of surgeries were considered: gastric bypass, sleeve gastrectomy, and adjustable gastric banding. A base-case analysis was performed for the population, the characteristics of which were obtained from surgery candidates in Italy. Results: In the base-case analysis, over 10 years, bariatric surgery led to cost increment of EUR 2,661 and generated additional 1.1 quality-adjusted life years (QALYs). Over a lifetime, surgery led to savings of EUR 8,649, additional 0.5 life years and 3.2 QALYs. Bariatric surgery was cost-effective at 10 years with an incremental cost-effectiveness ratio of EUR 2,412/QALY and dominant over conservative management over a lifetime. Conclusion: In a comprehensive decision analytic model, a current mix of surgical methods for bariatric surgery was cost-effective at 10 years and cost-saving over the lifetime of the Italian patient cohort considered in this analysis.

Populations of honey bees have declined worldwide in recent years. One suspected cause is the widespread use of pesticides in agriculture. Experiments were conducted to examine potential exposure routes of pesticides to honey bees in the Midsouth. Neonicotinoid seed treatment compounds were studied to determine the rate at which they drift during planting and the rate at which they diminish in crop tissue during crop development. Honey bee foraging activity in Midsouth crops was observed to determine when and at what densities foraging honey bees could be active during pesticide applications. This project was designed to aid in understanding the risks that pesticides could potentially pose to honey bees in the Midsouth.

Dear Editor, We are grateful for having the possibility to comment on the “Letter to the editor” regarding our article “Bariatric Surgery can Lead to Net Cost Savings to Health Care Systems: Results from a Comprehensive European Decision Analytic Model”. Fildes et al. have compared our data and results with those from the Swedish Obese Subjects study [1]. Our results are to 98 % based on gastric bypass surgery, the dominating procedure in Sweden and in Europe. The SOS study comprises only 13 % gastric bypass patients, with the majority of patients operated with purely restrictive operations, 68 % vertical banded gastroplasty (VBG) and 19 % gastric banding. It has been clearly shown that VBG is accompanied by high costs, since up to 89 % of patients need a conversion [2]. In our analysis, reduction of use of gastric bypass with corresponding increase in other types of surgeries led to reduction of cost-saving effect. The comparison with the report by Weiner et al. [3] is not quite appropriate either. That study has observed costs over a 6-year period for a group of bariatric surgery patients, most of whom had had a gastric bypass, laparoscopic (38.3 %) or open (35.4 %). However, the control group was chosen because patients had diseases that were obesity-related. The study reported a significant loss to follow-up over 6 years. Total costs were higher in years 2 and 3 for the surgery group, but these differences disappeared with time. Weiner et al. did not have data beyond year 6. Since we report that the economic benefit of surgery to health care system appears after 17 years, we believe the results from the Weiner’s study do not contradict our conclusion. Limited duration of follow-up is an obvious and most common limitation of published empirical research of economic consequences of bariatric surgery. Due to the initial high cost of surgery, cumulative cost of surgical treatment has shown to be higher compared with cumulative cost of alternative conservative management in a short- and mid-term time horizon. To overcome this limitation and to incorporate long-term consequence of treatments, we have employed lifetime horizon in our model. Fildes et al. had commented on omitting some of obesity-related costs in our analysis, which can contribute to cost-saving effect. We have considered the costs, related to surgery, surgical complications, treatment of diabetes and cardiovascular disorders. These costs constitute about 80 % of total obesity-related cost as demonstrated in earlier [4–6] studies, although was reported to be lower in more recent studies [7]. Swedish cost-of-illness studies in obesity have also focused only on diabetes and cardiovascular outcomes [8]. In our opinion, the most important costs are included into analysis. Nevertheless, we agree that that with evolvement of treatments (e.g. for cancer), the relative weight of these cost items may be greater over the time. We agree with the comment that validation of the model with studies of bariatric surgery is of high value. In our analysis, incidence and remission of diabetes were validated with the Scandinavian Obesity Surgery Registry, and the number of cardiovascular outcomes and mortality was validated with the Action for Health in Diabetes (AHEAD) study of lifestyle interventions, which included 5145 overweight or obese patients with type 2 diabetes (start BMI for validation was 35.9 kg/m2) [9]. It is acknowledged that there would always be not enough validation attempts, as clinical data evolve over time. We agree that additional specific validation exercises would be of benefit. In their comment, Fildes et al. focused on the overall conclusion from the analysis, although important sub-group differences in economic outcomes were shown. Thus, cost-saving effect was reported in the base-case analysis (with characteristics of the cohort, mimicking characteristics of real surgical candidates in Sweden) and single-cohort analysis of diabetic patients and severe to super obese non-diabetic patients. But in single-cohort analysis, we did not observe cost savings in patients with moderate and severe obesity and no diabetes at baseline. Bariatric surgery is a good example of a rapidly evolving area with changes of surgical techniques, dramatic reduction in the use of open surgical approach and improved safety. Empirical economic data, although being the source of information of the greatest validity, are always available with delay, usually have limited follow-up and often do not correspond to the current treatment practice. In this case, decision analytic modelling has an inevitable complementary role to inform clinical and policy decision-making, acknowledging its simplification over reality. Omitting data generated by comprehensive modelling would lead to underestimation of true economic value of modern bariatric surgery.

Glutathione S-transferases (GSTs ; EC 2.5.1.18) have recently been proposed to form one large group among the auxin-induced proteins. However, the properties and regulation of such auxin-responsive GSTs in the plant still await detailed investigation. In this study, a 2,4-dichloro-phenoxyacetic acid (2,4-D)-inducible GST isozyme from soybean (Glycine max [L.] Merr. cv. Williams) was purified to near homogeneity by anion-exchange and affinity chromatography on S-hexylglutathione agarose. The native-enzyme had a molecular mass of 49 kDa, as determined by gel filtration, and consisted of 26-kDa subunits. The purified GST conjugated glutathione to 1--chloro-2,4-dinitrobenzene and to the herbicide metolachlor, but not to the other GST substrates atrazine, fluorodifen or trans-cinnamic acid. The N-terminal amino acid sequence shared significant homology with the deduced polypeptide sequences of two 2,4-D-inducible genes from tobacco, parA and CNT107. The levels of the 26-kDa GST subunit protein in soybean hypocotyls were analysed by immunoblotting. At micromolar concentrations, 2,4-D induced a transient increase in net accumulation of GST, whereas indole-3-acetic acid or 1 -naphthaleneacetic acid did not increase the GST levels. Known inhibitors of polar auxin transport, including 2,3,5-tri-iodobenzoic acid, N-1-naphthylphthalamic acid and analogues thereof, differed widely in their ability to elicit GST protein accumulation. It is concluded that the induction of soybean GST by 2,4-D and by some of the auxin transport inhibitors is not related to auxin activity or to changes in the endogenous auxin levels.