• Beyond bioproductivity: Engaging local perspectives in land degradation monitoring and assessment

      Herrmann, Stefanie; Diouf, Abdoul Aziz; Sall, Ibrahima; Univ Arizona (ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2020-02)
      Land degradation monitoring and assessment in the Sahel zone has relied substantially on temporal trends of remote sensing-based vegetation indices, which are proxies for the bioproductivity of the land. However, prior studies have shown that negative or positive trends in bioproductivity are not necessarily associated with degradation or improvement of land condition. In this short communication, while acknowledging the contributions of remote sensing-based indices and global-scale datasets to dismantling an outdated desertification narrative, we argue that local land users have much to contribute to our understanding of land degradation, and particularly to ensuring that scientific assessments of degradation capture variables relevant to them. We used the participatory photo elicitation method in three sites in the Senegalese Ferlo in order to elicit local pastoralists' perspectives on land degradation and identify the indicators that they use to characterize pasture quality, while empowering them to lead the discussion. The discussion revealed indicators far beyond bioproductivity, including livestock performance as well as composition and quality of the herbaceous and woody vegetative cover, invasive species, soil quality and water availability. We found that the pastoralists' knowledge and interest in the issue could potentially be harnessed more systematically, and at larger scales, in order to build a spatially explicit field-based knowledge base of land degradation complementary to remote sensing-based maps of trends in bioproductivity. Such a dataset could serve as a standalone product or as a reference dataset for development and validation of remote sensing-based indicators.
    • A hybrid metaheuristic algorithm for a profit-oriented and energy-efficient disassembly sequencing problem

      Lu, Qi; Ren, Yaping; Jin, Hongyue; Meng, Leilei; Li, Lei; Zhang, Chaoyong; Sutherland, John W.; Univ Arizona, Dept Syst & Ind Engn (PERGAMON-ELSEVIER SCIENCE LTD, 2020-02)
      Value recovery from end-of-life products plays a key role in sustainability and circular economy, which starts with disassembly of products into components for reuse, remanufacturing, or recycling. As the process is often complex, a disassembly sequencing problem (DSP) studies how to optimally disassemble products considering the physical constraints between subassemblies/disassembly tasks for maximum profit. With a growing attention on energy conservation, this paper addresses a profit-oriented and energy-efficient DSP (PEDSP), whereby not only the profit is maximized, but also energy consumption is accounted as an important decision criterion. In this work, a disassembly AND/OR graph (DAOG) is used to model a disassembly diagram for a product, in which the 'AND' and 'OR' relations illustrate precedence relationships between subassemblies. Based on the DAOG, we propose a hybrid multi-objective metaheuristic that integrates an artificial bee colony algorithm, a non-dominated sorting procedure, and a variable neighborhood search approach to solve the PEDSP for Pareto solutions. The proposed method is applied to real-world cases (i.e., a simple ballpoint pen and a relatively complex radio) and compared with other multi-objective algorithms. The results indicate that our method can quickly produce a Pareto front that outperforms the alternative approaches.
    • The effect of CPAP on HRQOL as measured by the Quality of Well-Being Self Administered Questionaire (QWB-SA)

      Batool-Anwar, Salma; Omobomi, Olabimpe; Quan, Stuart F; Univ Arizona, Coll Med; Univ Arizona, Asthma & Airways Dis Res Ctr (Arizona Thoracic Society, 2020-01-14)
      Background: To examine the effect of continuous positive airway pressure (CPAP) on Health-related quality of life (HRQoL) as measured by the Quality of Well Being Self-Administered questionnaire (QWB-SA). Methods: Participants from The Apnea Positive Pressure Long-term Efficacy Study (APPLES); a 6-month multicenter randomized, double-blinded intention to treat study, were included in this analysis. The participants with an apnea-hypopnea index >10 events/hour initially randomized to CPAP or Sham group were asked to complete QWB-SA at baseline, 2, 4, and 6-month visits. Results: There were no group differences among either the CPAP or Sham groups. "Mean age was 52±12 [SD] years, AHI 40±25 events/hr, BMI 32±7.1 kg/m2, and Epworth Sleepiness Score (ESS) 10±4 of 24 points." QWB-SA scores were available at baseline, and 2, 4 & 6 months after treatment in CPAP (n 558) and Sham CPAP (n 547) groups. There were no significant differences in QWB scores among mild, moderate or severe OSA participants at baseline. Modest improvement in QWB scores was noted at 2, 4 and 6- months among both Sham and CPAP groups (P <0.05). However, no differences were observed between Sham CPAP and CPAP at any time point. Comparison of the QWB-SA data from the current study with published data in populations with chronic illnesses demonstrated that the impact of OSA is no different than the effect of AIDS and arthritis. Conclusion: Although the QoL measured by the QWB-SA was impaired in OSA it did not have direct proportionality to OSA severity.
    • Comparative pharmacokinetic study of PEGylated gemcitabine and gemcitabine in rats by LC-MS/MS coupled with pre-column derivatization and MS technique

      Yin, Lei; Ren, Tianming; Zhao, Shiying; Shi, Meiyun; Gu, Jingkai; Univ Arizona, Coll Pharm (ELSEVIER, 2020-01-01)
      Gemcitabine is a small molecular antitumor compound used to treat many types of solid tumors. The clinical application of gemcitabine is limited by its short biological half-life, rapid metabolism and poor tumor tissue targeting. The covalent attachment of polyethylene glycol to gemcitabine is a promising technique to overcome these limitations. After PEGylation, PEGylated gemcitabine could be metabolized into gemcitabine and its metabolites in vivo. Due to the scale effect of PEGylated gemcitabine, the DMPK process of the original drug is greatly changed. Therefore, understanding the pharmacokinetic behavior of PEGylated gemcitabine, gemcitabine and the metabolite dFdU in vivo is really important to clarify the antitumoral activity of these compounds. It would also guide the development of other PEGylated drugs. Due to the complex structure and diverse physiochemical property of PEG, direct quantification analysis of PEGylated gemcitabine presented many challenges in terms of assay sensitivity, selectivity, and robustness. In this article, a data-independent acquisition method, MSALL-based approach using electrospray ionization (ESI) coupled quadrupole time of flight mass spectrometry (MS), was utilized for the determination of PEGylated gemcitabine in rat plasma. The technique consists of a Q1 mass window through all the precursor ions, fragmenting and recording all product ions. PEGylated gemcitabine underwent dissociation in collision cell to generate a series of PEG related ions at m/z 89.0604, 133.0868, 177.1129 of 2, 3, 4 repeating ethylene oxide subunits and PEGylated gemcitabine related ions at m/z 112.0514. PEGylated gemcitabine was detected by the high resolution extracted ions based on the specific compound. For gemcitabine and dFdU, the study used derivatization of these high polarity compounds with dansyl chloride to improve their chromatographic retention. This paper describes comparative pharmacokinetic study of PEGylated gemcitabine and gemcitabine in rats by LC-MS/MS coupled with pre-column derivatization and MSALL technique. The results show that PEGylation could reduce the drug clearance of the conjugated compounds and increase the drug plasma half-life. After administration of PEGylated gemcitabine, the exposure of the free gemcitabine in vivo is lower than administration of gemcitabine, which means that PEGylated gemcitabine possesses lower toxicity compared with gemcitabine.
    • Comparing Contract Administration Functions for Alternative and Traditional Delivery of Highway Projects

      Papajohn, Dean; El Asmar, Mounir; Molenaar, Keith R.; Alleman, Doug; Univ Arizona, Dept Civil & Architectural Engn & Mech, Practice (ASCE-AMER SOC CIVIL ENGINEERS, 2020-01-01)
      Agency roles and responsibilities for contract administration depend on the contracting method. The Federal Highway Administration (FHWA) has encouraged agencies to consider alternative contracting methods (ACMs) like design-build (DB) and construction manager/general contractor (CM/GC). There is a lack of information available to transportation agencies regarding the details of agency-performed contract administration functions between ACMs and traditional design-bid-build (DBB) delivery. This paper contributes to the existing body of knowledge of highway contract administration by revealing similarities and differences between agency-performed contract administration functions across contracting methods through the development of integrated definition function models (IDEF0). These IDEF0 models depict the hierarchy of contract administration functions for DBB, CM/GC, and DB highway projects and reveal differences such as developing alignment, administering preconstruction services, managing work packages, and creating risk pools for additional scope. The findings can help agencies make more informed decisions about selecting and administering contracting methods, especially as they relate to establishing the level of effort and skills needed for administering projects under various contracting methods. In addition, these IDEF0 models provide a novel framework for future research on highway contract administration.
    • Analysis, Simulation, and Optimization of Stochastic Vesicle Dynamics in Synaptic Transmission

      Zhang, Calvin; Peskin, Charles S.; Univ Arizona, Dept Math (WILEY, 2020-01)
      Synaptic transmission is the mechanism of information transfer from one neuron to another (or from a neuron to a muscle or to an endocrine cell). An important step in this physiological process is the stochastic release of neurotransmitter from vesicles that fuse with the presynaptic membrane and spill their contents into the synaptic cleft. We are concerned here with the formulation, analysis, and simulation of a mathematical model that describes the stochastic docking, undocking, and release of synaptic vesicles and their effect on synaptic signal transmission. The focus of this paper is on the parameter p(0), the probability of release for each docked vesicle when an action potential arrives. We study the influence of this parameter on the statistics of the release process and on the theoretical capability of the model synapse in reconstructing various desired outputs based on the timing and amount of neurotransmitter release. This theoretical capability is assessed by formulating and solving an optimal filtering problem. Methods for parameter identification are proposed and applied to simulated data. (c) 2019 Wiley Periodicals, Inc.
    • Fatiga de enfermeras, el sueño y la salud, y garantizar la seguridad del paciente y del publico: Unir dos idiomas

      Baldwin, Carol M; Quan, Stuart F; Univ Arizona, Asthma & Airways Dis Res Ctr; Univ Arizona, Coll Med (Arizona Thoracic Society, 2019-12-29)
    • Linear Stability in the Inner Heliosphere: Helios Re-evaluated

      Klein, K. G.; Martinović, M.; Stansby, D.; Horbury, T. S.; Univ Arizona, Lunar & Planetary Lab; Univ Arizona, Dept Planetary Sci (IOP PUBLISHING LTD, 2019-12-23)
      Wave–particle instabilities driven by departures from local thermodynamic equilibrium have been conjectured to play a role in governing solar wind dynamics. We calculate the statistical variation of linear stability over a large subset of Helios I and II observations of the fast solar wind using a numerical evaluation of the Nyquist stability criterion, accounting for multiple sources of free energy associated with protons and helium including temperature anisotropies and relative drifts. We find that 88% of the surveyed intervals are linearly unstable. The median growth rate of the unstable modes is within an order of magnitude of the turbulent transfer rate, fast enough to potentially impact the turbulent scale-to-scale energy transfer. This rate does not significantly change with radial distance, though the nature of the unstable modes, and which ion components are responsible for driving the instabilities, does vary. The effect of ion–ion collisions on stability is found to be significant; collisionally young wind is much more unstable than collisionally old wind, with very different kinds of instabilities present in the two kinds of wind.
    • Alignment of stakeholder agendas to facilitate the adoption of school-supervised asthma therapy

      Trivedi, Michelle; Patel, Janki; Hoque, Shushmita; Mizrahi, Raphael; Biebel, Kathleen; Phipatanakul, Wanda; Lemon, Stephenie C; Byatt, Nancy; Gerald, Lynn B; Rosal, Milagros; et al. (WILEY, 2019-12-19)
      Background School-supervised inhaled corticosteroid (ICS) therapy improves pediatric asthma medication adherence, outcomes, and morbidity. However, school-supervised ICS therapy has not been widely adopted into practice. We developed Asthma Link (TM) as a sustainable, low-cost model of school-supervised asthma therapy, designed for real-world adoption. Initial outcomes of Asthma Link (TM) demonstrated a significant improvement in health outcomes. Objective In this study, we examined the perspectives of Asthma Link (TM) participants to identify systems-level barriers and facilitators to refine the Asthma Link (TM) protocol and facilitate real-world uptake of school-supervised asthma therapy. Methods Using qualitative research methods, we interviewed 29 participants in Asthma Link (TM) from 2016 to 2018. Semi-structured interviews were conducted over the phone. Interviews were transcribed and the transcripts were coded to identify major themes within and across stakeholder groups. Results Stakeholders agreed on many facilitators for successful Asthma Link (TM) execution including the brief and easy to follow procedures and the perceived beneficial health impacts for children involved. Some of the barriers identified were deviations from the protocol and insurance companies denying coverage for two inhalers. However, the participants did propose solutions to address these barriers. Conclusion Asthma Link (TM) is a low-cost, sustainable model of school-supervised asthma therapy that leverages the established infrastructure and collaboration of medical providers, school staff, and families. In this study, we elicited the perspectives from these stakeholder groups and identified an agreement in several facilitators, barriers, and proposed solutions that will ultimately inform refinement of the program protocol and support real-world adoption of Asthma Link (TM) and other similar models.
    • Carrots and sticks: Experimental evidence of vote-buying and voter intimidation in Guatemala

      Gonzalez-Ocantos, Ezequiel; de Jonge, Chad Kiewiet; Meléndez, Carlos; Nickerson, David; Osorio, Javier; Univ Arizona, Sch Govt & Publ Policy (SAGE PUBLICATIONS LTD, 2019-12-17)
      How do parties target intimidation and vote-buying during elections? Parties prefer the use of carrots over sticks because they are in the business of getting voters to like them and expect higher legitimacy costs if observers expose intimidation. However, their brokers sometimes choose intimidation because it is cheaper and possibly more effective than vote-buying. Specifically, we contend that brokers use intimidation when the cost of buying votes is prohibitively high; in interactions with voters among whom the commitment problem inherent to clientelistic transactions is difficult to overcome; and in contexts where the risk of being denounced for violence is lower. We probe our hypotheses about the different profile of voters targeted with vote-buying and intimidation using two list experiments included in an original survey conducted during the 2011 Guatemalan general elections. The list experiments were designed to overcome the social desirability bias associated with direct questions about illegal or stigmatized behaviors. Our quantitative analysis is supplemented by interviews with politicians from various parties. The analysis largely confirms our expectations about the diametrically opposed logics of vote-buying and intimidation targeting, and illuminates how both are key components of politics in a country with weak parties and high levels of violence.
    • Economic performance of membrane distillation configurations in optimal solar thermal desalination systems

      Karanikola, Vasiliki; Moore, Sarah E.; Deshmukh, Akshay; Arnold, Robert G.; Elimelech, Menachem; Sáez, A. Eduardo; Univ Arizona, Dept Chem & Environm Engn (ELSEVIER, 2019-12-15)
      In this study we provide a comprehensive evaluation of the economic performance and viability of solar membrane distillation (MD). To achieve this goal, process models based on mass and energy balances were used to find the minimum cost of water in MD systems. Three MD configurations: direct contact, sweeping gas, and vacuum MD, were compared in terms of economic cost and energy requirements in optimized, solar-driven desalination systems constrained to produce 10 m(3) d(-1) of distillate from 3.5% or 15% salinity water. Simulation results were used to calculate the water production cost as a function of 13 decision variables, including equipment size and operational variables. Non-linear optimization was performed using the particle swarm algorithm to minimize water production costs and identify optimal values for all decision variables. Results indicate that vacuum MD outperforms alternative MD configurations both economically and energetically, desalting water at a cost of less than $15 per cubic meter of product water (both initial salt levels). The highest fraction of total cost for all configurations at each salinity level was attributed to the solar thermal collectors-approximately 25% of the total present value cost. Storing energy in any form was economically unfavorable; the optimization scheme selected the smallest battery and hot water tank size allowed. Direct contact MD consumed significantly more energy (primarily thermal) than other MD forms, leading to higher system economic costs as well.
    • Beavers alter stream macroinvertebrate communities in north-eastern Utah

      Washko, Susan; Roper, Brett; Atwood, Trisha B.; Univ Arizona, Sch Nat Resources & Environm (WILEY, 2019-12-15)
      Understanding changes in macroinvertebrate communities is important because they play a large role in stream ecosystem functioning, and they are an important food resource for fish. Beaver-induced changes to stream morphology could alter macroinvertebrate communities, which in turn could affect food webs and ecosystem function. However, studies investigating the effects of North American beaver activities on macroinvertebrates are rare in the inter-mountain west, an area with high potential for beaver-assisted restoration. The aim of this study was to quantify differences in the macroinvertebrate community between unaltered segments of streams and within beaver ponds in north-eastern Utah, U.S.A. We assessed macroinvertebrate species richness, biomass, density, functional feeding group composition, mobility group composition, and macroinvertebrate habitat characteristics to test the hypothesis that macroinvertebrate communities will differ among habitat types (undammed stream segments and beaver ponds) in beaver-occupied streams. Beaver pond communities significantly differed from lotic reach communities in many ways. Beaver ponds were less diverse with 25% fewer species. Although there was variability among streams, in general, beaver ponds had 75% fewer individuals and 90% lower total macroinvertebrate biomass compared to lotic reaches. Regarding functional feeding groups, beaver ponds contained more engulfers, while lotic reaches contained more scrapers, filterers, and gatherers. For mobility groups, beaver ponds had more sprawlers, while lotic reaches had more clingers. Swimmers were also more prevalent in lotic reaches, although this is probably due to the abundance of Baetis within lotic reaches. More beaver pond taxa were classified as lentic-dwelling insects, while more lotic reach taxa were categorised as preferring lotic habitats. The creation of ponds by beavers fundamentally altered the macroinvertebrate community in north-eastern Utah streams. Such changes to stream macroinvertebrate communities suggest that recolonisation of beavers across North America may be altering stream functioning and food webs. Our study highlights the need to further investigate the effects of beaver recolonisation on stream communities.
    • Developing an effective inpatient learning climate

      Harper, Beth D; Buchanan, April O; Cramton, Rachel Em; Gourishankar, Anand; King, Marta; Molas-Torreblanca, Kira; Patra, Kamakshya P; Pomeroy, Brian; Potisek, Nicholas M; Seelbach, Elizabeth; et al. (WILEY, 2019-12-11)
    • A bifurcation theorem for nonlinear matrix models of population dynamics

      Cushing, J. M.; Farrell, Alex P.; Univ Arizona, Dept Math (TAYLOR & FRANCIS LTD, 2019-12-08)
      We prove a general theorem for nonlinear matrix models of the type used in structured population dynamics that describes the bifurcation that occurs when the extinction equilibrium destabilizes as a model parameter is varied. The existence of a bifurcating continuum of positive equilibria is established, and their local stability is related to the direction of bifurcation. Our theorem generalizes existing theorems found in the literature in two ways. First, it allows for a general appearance of the bifurcation parameter (existing theorems require the parameter to appear linearly). This significantly widens the applicability of the theorem to population models. Second, our theorem describes circumstances in which a backward bifurcation can produce stable positive equilibria (existing theorems allow for stability only when the bifurcation is forward). The signs of two diagnostic quantities determine the stability of the bifurcating equilibrium and the direction of bifurcation. We give examples that illustrate these features.
    • Not the Desired Outcome: Groupthink Undermines the Work of a Literacy Council

      Jaeger, Elizabeth L.; Univ Arizona, Dept Teaching Learning & Sociocultural Studies (SAGE PUBLICATIONS INC, 2019-12-06)
      A history of school reform failure has prompted concern among literacy researchers and practitioners alike. This article considers the case of a school Literacy Council and its unsuccessful efforts to improve the school's literacy environment. Mobilizing Janis's notion of groupthink, I examine discourse among group members and suggest that characteristics of groupthink-problematic antecedents cultivating troubling decision-making symptoms-led to unsuccessful outcomes. During times of low stress, Literacy Council members collaborated effectively, but when the principal's unilateral curricular decision raised stress levels, the group succumbed to groupthink and experienced failure. This study offers implications for other groups which are shaken by a late-emerging threat. I argue that groupthink theory shines light on problems with group interaction. An awareness of precursors to and symptoms of groupthink may support work teams as they propose and enact important change.
    • Winners and losers in US-China scientific research collaborations

      Lee, Jenny J.; Haupt, John P.; Univ Arizona, Ctr Study Higher Educ (SPRINGER, 2019-12-03)
      This study examined the patterns and nature of science co-publications between the USA and China. Based on a scientometric study of Scopus co-publications over the past 5 years, the results demonstrated a continuous rise of bilateral collaboration between the two countries. Challenging the US political rhetoric and attempts to curb international research engagement with China, the findings demonstrated ways that China plays a leading role in US-China research collaboration, based on first authorship and governmental funding patterns. Findings also showed that over the past 5 years, US research article publications would have declined without co-authorship with China, whereas China’s publication rate would have risen without the USA. Using zero-sum and positive-sum frameworks, this study shows the benefits of US collaboration with China for both the US nation-state and global science.
    • Recognition and Drawing of Stick Graphs

      De Luca, Felice; Hossain, Md Iqbal; Kobourov, Stephen; Lubiw, Anna; Mondal, Debajyoti; Univ Arizona, Dept Comp Sci (ELSEVIER, 2019-12-03)
      A Stick graph is an intersection graph of axis-aligned segments such that the left endpoints of the horizontal segments and the bottom end-points of the vertical segments lie on a "ground line," a line with slope - 1. It is an open question to decide in polynomial time whether a given bipartite graph G with bipartition A boolean OR B has a Stick representation where the vertices in A and B correspond to horizontal and vertical segments, respectively. We prove that G has a Stick representation if and only if there are orderings of A and B such that G's bipartite adjacency matrix with rows A and columns B excludes three small 'forbidden' submatrices. This is similar to characterizations for other classes of bipartite intersection graphs. We present an algorithm to test whether given orderings of A and B permit a Stick representation respecting those orderings, and to find such a representation if it exists. The algorithm runs in time linear in the size of the adjacency matrix. For the case when only the ordering of A is given, or neither ordering is given, we present some partial results about graphs that are, or are not, Stick representable. (C) 2019 Elsevier B.V. All rights reserved.
    • Differential resistance and resilience of functional groups to livestock grazing maintain ecosystem stability in an alpine steppe on the Qinghai-Tibetan Plateau

      Ganjurjav, Hasbagan; Zhang, Yong; Gornish, Elise S; Hu, Guozheng; Li, Yue; Wan, Yunfan; Gao, Qingzhu; Univ Arizona, Sch Nat Resources & Environm (ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2019-12-01)
      Ecosystem stability is one of the main factors maintaining ecosystem functioning and is closely related to temporal variability in productivity. Resistance and resilience reflect tolerance and recovering ability, respectively, of a plant community under perturbation, which are important for maintaining the stability of ecosystems. Generally, heavy grazing reduces the stability of grassland ecosystems, causing grassland degradation. However, how livestock grazing affects ecosystem stability is unclear in alpine steppe ecosystems. We conducted a five-year grazing experiment with Tibetan sheep in a semi-arid alpine steppe on the Qinghai-Tibetan Plateau, China. The experimental treatments included no grazing (NG), light grazing (LG, 2.4 sheep per ha), moderate grazing (MG, 3.6 sheep per ha) and heavy grazing (HG, 6.0 sheep ha). We calculated resistance and resilience of three plant functional groups and ecosystem stability under the three grazing intensities using aboveground primary productivity. The results showed that with increasing grazing intensity, aboveground biomass of each functional group significantly decreased. As grazing intensity increased, the resistance of forbs first increased then decreased. The resilience of graminoids in HG was significantly lower than in LG plots, but the resilience of legumes in HG was higher than in LG and MG plots. The resilience of graminoids was significantly higher than legume and forbs under LG and MG treatments. In HG treatments, resilience of legumes was higher than graminoids and forbs. Ecosystem stability did not change under different grazing intensities, because of dissimilar performance of the resilience and resistance of functional groups. Our results highlight how the differential resistance and resilience of different function groups facilitate the tolerance of alpine steppe to grazing under even a heavy intensity. However, the degradation risk of alpine steppe under heavy grazing still needs to be considered in grassland management due to sharp decreases of productivity.
    • Multiple reservoirs of volatiles in the Moon revealed by the isotopic composition of chlorine in lunar basalts

      Barnes, Jessica J.; Franchi, Ian A.; McCubbin, Francis M.; Anand, Mahesh; Univ Arizona, Lunar & Planetary Lab (PERGAMON-ELSEVIER SCIENCE LTD, 2019-12-01)
      The isotopes of chlorine (Cl-37 and Cl-35) are highly fractionated in lunar samples compared to most other Solar System materials. Recently, the chlorine isotope signatures of lunar rocks have been attributed to large-scale degassing processes that occurred during the existence of a magma ocean. In this study we investigated how well a suite of lunar basalts, most of which have not previously been analyzed, conform to previous models. The Cl isotope compositions (delta Cl-37 (parts per thousand) = [(Cl-37/Cl-35(sample)/Cl-37/Cl-35(SMOC)) - 1] x 1000, where SMOC refers to standard mean ocean chloride) recorded range from similar to+7 to +14 parts per thousand (Apollo 15), +10 to +19 parts per thousand (Apollo 12), +9 to +15 parts per thousand (70017), +4 to +8 parts per thousand (MIL 05035), and +15 to +22 parts per thousand (Kalahari 009). The Cl isotopic data from the present study support the mixing trends previously reported by Boyce et al. (2015) and Barnes et al. (2016), as the Cl isotopic composition of apatites are positively correlated with bulk-rock incompatible trace element abundances in the low-Ti basalts, inclusive of low-Ti and KREEP basalts. This trend has been interpreted as evidence that incompatible trace elements, including Cl, were concentrated in the urKREEP residual liquid of the lunar magma ocean, rather than the mantle cumulates, and that urKREEP Cl had a highly fractionated isotopic composition. The source regions for the basalts were thus created by variable mixing between the mantle (Cl-poor and relatively unfractionated) and urKREEP. The high-Ti basalts show much more variability in measured Cl isotope ratios and scatter around the trend formed by the low-Ti basalts. Most of the data for lunar meteorites also fits the mixing of volatiles in their sources, but Kalahari 009, which is highly depleted in incompatible trace elements, contains apatites with heavily fractionated Cl isotopic compositions. Given that Kalahari 009 is one of the oldest lunar basalts and ought to have been derived from very early-formed mantle cumulates, a heavy Cl isotopic signature is likely not related to its mantle source, but more likely to magmatic or secondary alteration processes, perhaps via impact-driven vapor metasomatism of the lunar crust. (C) 2019 The Authors. Published by Elsevier Ltd.
    • Intimate stimuli result in fronto-parietal activation changes in anorexia nervosa

      van Zutphen, L; Maier, S; Siep, N; Jacob, G A; Tüscher, O; van Elst, L Tebartz; Zeeck, A; Arntz, A; O'Connor, M-F; Stamm, H; et al. (SPRINGER, 2019-12-01)
      Background Intimacy is a key psychological problem in anorexia nervosa (AN). Empirical evidence, including neurobiological underpinnings, is however, scarce. Objective In this study, we evaluated various emotional stimuli including intimate stimuli experienced in patients with AN and non-patients, as well as their cerebral response. Methods Functional magnetic resonance imaging was conducted using stimuli with positive, neutral, negative and intimate content. Participants (14 AN patients and 14 non-patients) alternated between passive viewing and explicit emotion regulation. Results Intimate stimuli were experienced less positively in AN patients compared to non-patients. AN patients showed decreased cerebral responses in superior parietal cortices in response to positive and intimate stimuli. Intimate stimuli led to stronger activation of the orbitofrontal cortex, and lower activation of the bilateral precuneus in AN patients. Orbitofrontal responses decreased in AN patients during explicit emotion regulation. Conclusions These results show that intimate stimuli are of particular importance in AN patients, who show experiential differences compared to non-patients and altered activation of orbitofrontal and parietal brain structures. This supports that AN patients have difficulties with intimacy, attachment, self-referential processing and body perception.