bluuebunny/crossref_metadata_2025 huggingface dataset:
An Analogue Approach to Identify Heavy Precipitation Events: Evaluation and Application to CMIP5 Climate Models in the United States
Authors: Gao Xiang , Schlosser C. Adam , Xie Pingping , Monier Erwan , Entekhabi Dara
Published: May 2014

An analogue method is presented to detect the occurrence of heavy precipitation events without relying on modeled precipitation. The approach is based on using composites to identify distinct large-scale atmospheric conditions associated with widespread heavy precipitation events across local scales. These composites, exemplified in the south-central, midwestern, and western United States, are derived through the analysis of 27-yr (1979–2005) Climate Prediction Center (CPC) gridded station data and the NASA Modern-Era Retrospective Analysis for Research and Applications (MERRA). Circulation features and moisture plumes associated with heavy precipitation events are examined. The analogues are evaluated against the relevant daily meteorological fields from the MERRA reanalysis and achieve a success rate of around 80% in detecting observed heavy events within one or two days. The method also captures the observed interannual variations of seasonal heavy events with higher correlation and smaller RMSE than MERRA precipitation. When applied to the same 27-yr twentieth-century climate model simulations from Phase 5 of the Coupled Model Intercomparison Project (CMIP5), the analogue method produces a more consistent and less uncertain number of seasonal heavy precipitation events with observation as opposed to using model-simulated precipitation. The analogue method also performs better than model-based precipitation in characterizing the statistics (minimum, lower and upper quartile, median, and maximum) of year-to-year seasonal heavy precipitation days. These results indicate the capability of CMIP5 models to realistically simulate large-scale atmospheric conditions associated with widespread local-scale heavy precipitation events with a credible frequency. Overall, the presented analyses highlight the improved diagnoses of the analogue method against an evaluation that considers modeled precipitation alone to assess heavy precipitation frequency.
Effects of Orography and Surface Heat Fluxes on the South Asian Summer Monsoon
Authors: Ma Ding , Boos William , Kuang Zhiming
Published: May 2014

A high-resolution (40 km horizontal) global model is used to examine controls on the South Asian summer monsoon by orography and surface heat fluxes. In a series of integrations with altered topography and reduced surface heat fluxes, monsoon strength, as indicated by a vertical wind shear index, is highly correlated with the amplitude of the maximum boundary layer equivalent potential temperature (θeb) over South Asia. Removal of the Tibetan Plateau while preserving the Himalayas and adjacent mountain ranges has little effect on monsoon strength, and monsoon strength decreases approximately linearly as the height of the Himalayas is reduced. In terms of surface heat flux changes, monsoon strength is most sensitive to those in the location of the θeb maximum just south of the Himalayas. These results are consistent with the recent idea that topography creates a strong monsoon by insulating the thermal maximum from dry extratropical air. However, monsoon strength is found to be more sensitive to variations in the θeb maximum when topography is altered than when surface heat fluxes are reduced, and it is suggested that free-tropospheric humidity changes lead to deviations from strict convective quasi equilibrium and cause this difference. When topography is reduced, dry extratropical air intrudes into the troposphere over the θeb maximum and is entrained by local deep convection, requiring a higher θeb to achieve convective equilibrium with a given upper-tropospheric temperature and associated balanced monsoon flow. These results illustrate potential complexities that need to be included in simple theories for monsoon strength built on strict convective quasi equilibrium.
Tracking Interannual Streamflow Variability with Drought Indices in the U.S. Pacific Northwest
Authors: Abatzoglou John T. , Barbero Renaud , Wolf Jacob W. , Holden Zachary A.
Published: May 2014

Drought indices are often used for monitoring interannual variability in macroscale hydrology. However, the diversity of drought indices raises several issues: 1) which indices perform best and where; 2) does the incorporation of potential evapotranspiration (PET) in indices strengthen relationships, and how sensitive is the choice of PET methods to such results; 3) what additional value is added by using higher-spatial-resolution gridded climate layers; and 4) how have observed relationships changed through time. Standardized precipitation index, standardized precipitation evapotranspiration index (SPEI), Palmer drought severity index, and water balance runoff (WBR) model output were correlated to water-year runoff for 21 unregulated drainage basins in the Pacific Northwest of the United States. SPEI and WBR with time scales encompassing the primary precipitation season maximized the explained variance in water-year runoff in most basins. Slightly stronger correlations were found using PET estimates from the Penman–Monteith method over the Thornthwaite method, particularly for time periods that incorporated the spring and summer months in basins that receive appreciable precipitation during the growing season. Indices computed using high-resolution climate surfaces explained over 10% more variability than metrics derived from coarser-resolution datasets. Increased correlation in the latter half of the study period was partially attributable to increased streamflow variability in recent decades as well as to improved climate data quality across the interior mountain watersheds.
Characterizing and Optimizing Precipitation Forecasts from a Convection-Permitting Ensemble Initialized by a Mesoscale Ensemble Kalman Filter
Authors: Schwartz Craig S. , Romine Glen S. , Smith Kathryn R. , Weisman Morris L.
Published: May 2014

Convection-permitting Weather Research and Forecasting (WRF) Model forecasts with 3-km horizontal grid spacing were produced for a 50-member ensemble over a domain spanning three-quarters of the contiguous United States between 25 May and 25 June 2012. Initial conditions for the 3-km forecasts were provided by a continuously cycling ensemble Kalman filter (EnKF) analysis–forecast system with 15-km horizontal grid length. The 3-km forecasts were evaluated using both probabilistic and deterministic techniques with a focus on hourly precipitation. All 3-km ensemble members overpredicted rainfall and there was insufficient forecast precipitation spread. However, the ensemble demonstrated skill at discriminating between both light and heavy rainfall events, as measured by the area under the relative operating characteristic curve. Subensembles composed of 20–30 members usually demonstrated comparable resolution, reliability, and skill as the full 50-member ensemble. On average, deterministic forecasts initialized from mean EnKF analyses were at least as or more skillful than forecasts initialized from individual ensemble members “closest” to the mean EnKF analyses, and “patched together” forecasts composed of members closest to the ensemble mean during each forecast interval were skillful but came with caveats. The collective results underscore the need to improve convection-permitting ensemble spread and have important implications for optimizing EnKF-initialized forecasts.
Effectiveness of health promotion programmes for truck drivers: A systematic review
Authors: Ng Mandy K , Yousuf Bilal , Bigelow Philip Lloyd , Van Eerd Dwayne
Published: May 2014

Objective:

To review the characteristics of effective health promotion interventions for reducing chronic diseases and their risk factors in truck drivers.

Methods:

MEDLINE (PubMed), SCOPUS, Web of Science Conference Proceedings, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the National Transportation Library were searched using keywords related to ‘truck driver’, ‘commercial driver’, and ‘health promotion’. Reference lists of relevant documents were hand-searched.

Results:

The search strategy identified 2,372 non-duplicate citations, of which nine met the inclusion criteria. These nine articles represented eight unique interventions. No studies measured chronic disease as an outcome. Six interventions incorporated multiple components and reported positive findings on various intermediate health outcomes (i.e. body mass index [BMI], % body fat) or health behaviours (i.e. nutrition, physical activity). The other two interventions modified work practices only, and found no significant improvements on fatigue and psychosocial measures.

Conclusion:

Health promotion interventions for truck drivers can improve both intermediate health outcomes and health behaviours over the short term. The small body of literature on health promotion interventions is a concern given that truck drivers are an at-risk population and their health impacts the safety of the driving public. Studies primarily focused on changes at the individual level and this is also a concern as environmental and work organisation factors are important determinants of both chronic disease outcomes and health-related behaviours in truck drivers. Future research should also include economic evaluations as well as methods to determine facilitators and barriers to programme participation and continuation.
Strengthening Theoretical Testing in Criminology Using Agent-based Modeling
Authors: Johnson Shane D. , Groff Elizabeth R.
Published: May 2014

Objectives:

The Journal of Research in Crime and Delinquency ( JRCD) has published important contributions to both criminological theory and associated empirical tests. In this article, we consider some of the challenges associated with traditional approaches to social science research, and discuss a complementary approach that is gaining popularity—agent-based computational modeling—that may offer new opportunities to strengthen theories of crime and develop insights into phenomena of interest.

Method:

Two literature reviews are completed. The aim of the first is to identify those articles published in JRCD that have been the most influential and to classify the theoretical perspectives taken. The second is intended to identify those studies that have used an agent-based model (ABM) to examine criminological theories and to identify which theories have been explored.

Results:

Ecological theories of crime pattern formation have received the most attention from researchers using ABMs, but many other criminological theories are amenable to testing using such methods.

Conclusion:

Traditional methods of theory development and testing suffer from a number of potential issues that a more systematic use of ABMs—not without its own issues—may help to overcome. ABMs should become another method in the criminologists toolbox to aid theory testing and falsification.
Perceiving Penn State
Authors: Huge Michael E. , Glynn Carroll J.
Published: May 2014

We examine the role of interpersonal discussion in an attempt to better understand talk’s contribution to perceived media impacts related to the sexual abuse scandal at Penn State University. Through the use of a survey conducted both in the state of Pennsylvania and nationally, we analyze how interpersonal discussion, issue involvement, media exposure, and affinity for the Penn State football team influence third-person perceptions (TPPs) related to the Penn State case. By examining a dynamic and polarizing social issue involving a previously well-regarded athletic program facing intense social and criminal scrutiny, we are able to better understand how TPPs are formed in the midst of an ongoing scandal. Results reveal the influence of interpersonal discussion—and especially interpersonal disagreement—as a key moderating variable in forming these perceptions of media influence.
Trencadís, Social Imaging Group (SIG)
Authors: Ramos Carles , Zelaskowski Peter
Published: May 2014

Trencadís, SIG is a new approach to working in large art therapy groups that has emerged out of a Barcelona based art therapy training that has from its inception included a group analytic large group as a principal experiential learning device. Trencadís, SIG combines two methods of working with groups: the group analytic large group and art psychotherapy. Within a structured framework we combine, in a single session model, image-making, metaphor and collaborative art work, using an art technique belonging to the local Catalan social unconscious.
Municipality and Neighborhood Influences on Volunteering in Later Life
Authors: Dury Sarah , Willems Jurgen , De Witte Nico , De Donder Liesbeth , Buffel Tine , Verté Dominique
Published: May 2014

This article explores the relationships between municipality features and volunteering by older adults. In the literature, strong evidence exists of the influence of place on older people’s health. However, the question how neighborhoods and municipalities promote or hinder volunteer participation remains under-explored. Data for the research are derived from the Belgian Aging Studies. We estimate logistic multilevel models for older individuals’ engagement in volunteering across 141 municipalities in Belgium ( N = 67,144). Analysis shows that neighborhood connectedness, neighborhood satisfaction, home ownership, and presence of services predict voluntary engagement at older ages. The findings support that perceptions and quality of social resources that relate to neighborhoods may be important factors to explain volunteering among older adults. Moreover, the findings suggest that volunteering in later life must be considered within a broader framework.
Curious energy consumers: Humans and nonhumans in assemblages of household practice
Authors: Strengers Yolande , Nicholls Larissa , Maller Cecily
Published: May 2014

In international energy policy, programmes and consumer research, a dominant ideal consumer is emerging. This consumer is typically a human adult who has the agency to make autonomous, functional and rational decisions about his or her household’s energy consumption. This article seeks to disrupt this dominant anthropocentric conceptualisation of the consumer and provide new ways of knowing and potentially intervening in the lives of energy consumers. Drawing on qualitative research conducted with householders living in Sydney, Australia, and theories of practice, materiality and agency from sociology and science and technology studies, we seek to understand consumers as human and nonhuman actants operating in distributed assemblages of practice. We explore the implications of conceptualising non-traditional consumers of energy, such as babies, pets, pests and pool pumps, as performers of or materials in practices that consume energy. Our analysis provides new ways of potentially intervening in patterns of energy consumption. We argue that policy makers need to refocus their attention on finding routes into assemblages of practice to achieve change. We conclude by calling for further exploration and recognition of the myriad curious consumers found in households.
The relation of sexual function to migraine-related disability, depression and anxiety in patients with migraine
Authors: Eraslan Defne , Yalınay Dikmen Pınar , Ilgaz Aydınlar Elif , İncesu Cem
Published: May 2014

Background

Depression and anxiety are two phenomena that affect quality of life as well as sexual function. Depression and anxiety levels are reported to be high in migraine sufferers. We aimed to understand whether sexual function in women with migraine was associated to migraine-related disability and frequency of migraine attacks, and whether this relationship was modulated by depressive and anxiety symptoms.

Methods

As migraine is more commonly seen in females, a total of 50 women with migraine were included. The diagnosis of migraine with or without aura was confirmed by two specialists in Neurology, according to the second edition of International Headache Society (IHS) International Classification of Headache Disorders (ICHD-II) in 2004. Migraine disability assessment scale score, female sexual function index scores, Beck depression inventory score and Beck anxiety inventory scores.

Results

Mean MIDAS score was 19.3 ± 12.8, and mean number of migraine attacks per month were 4.3 ± 2.7. Mean Female Sexual Function Index score was 20.9 ± 5.9 and 90% of patients had sexual dysfunction. Sexual dysfunction was not related to MIDAS score or frequency and severity of attacks. No relationship between sexual function and anxiety was found, whereas severity of depressive symptoms was closely related to sexual function. Depressive symptoms affected all dimensions of sexual function, except for pain.

Conclusion

Sexual dysfunction seemed to be very common in our patients with migraine, while not related to migraine related disability, frequency of attacks and migraine severity or anxiety. The most important factor that predicted sexual function was depression, which was also independent of disease severity and migraine related disability. While future larger scale studies are needed to clarify the exact relationship, depressive and sexual problems should be properly addressed in all patients with migraine, regardless of disease severity or disability.
RGD-conjugated silica-coated gold nanorods on the surface of carbon nanotubes for targeted photoacoustic imaging of gastric cancer
Authors: Wang Can , Bao Chenchen , Liang Shujing , Fu Hualin , Wang Kan , Deng Min , Liao Qiande , Cui Daxiang
Published: May 2014

Herein, we reported for the first time that RGD-conjugated silica-coated gold nanorods on the surface of multiwalled carbon nanotubes were successfully used for targeted photoacoustic imaging of in vivo gastric cancer cells. A simple strategy was used to attach covalently silica-coated gold nanorods (sGNRs) onto the surface of multiwalled carbon nanotubes (MWNTs) to fabricate a hybrid nanostructure. The cross-linked reaction occurred through the combination of carboxyl groups on the MWNTs and the amino group on the surface of sGNRs modified with a silane coupling agent. RGD peptides were conjugated with the sGNR/MWNT nanostructure; resultant RGD-conjugated sGNR/MWNT probes were investigated for their influences on viability of MGC803 and GES-1 cells. The nude mice models loaded with gastric cancer cells were prepared, the RGD-conjugated sGNR/MWNT probes were injected into gastric cancer-bearing nude mice models via the tail vein, and the nude mice were observed by an optoacoustic imaging system. Results showed that RGD-conjugated sGNR/MWNT probes showed good water solubility and low cellular toxicity, could target in vivo gastric cancer cells, and obtained strong photoacoustic imaging in the nude model. RGD-conjugated sGNR/MWNT probes will own great potential in applications such as targeted photoacoustic imaging and photothermal therapy in the near future.
PyCX: a Python-based simulation code repository for complex systems education
Authors: Sayama Hiroki
Published: May 2014

We introduce PyCX, an online repository of simple, crude, easy-to-understand sample codes for various complex systems simulation, including iterative maps, cellular automata, dynamical networks and agent-based models. All the sample codes were written in plain Python, a general-purpose programming language widely used in industry as well as in academia, so that students can gain practical skills for both complex systems simulation and computer programming simultaneously. The core philosophy of PyCX is on the simplicity, readability, generalizability and pedagogical values of simulation codes. PyCX has been used in instructions of complex systems modeling at several places with successful outcomes.
Aldehyde dehydrogenase and estrogen receptor define a hierarchy of cellular differentiation in the normal human mammary epithelium
Authors: Honeth Gabriella , Lombardi Sara , Ginestier Christophe , Hur Minhee , Marlow Rebecca , Buchupalli Bharath , Shinomiya Ireneusz , Gazinska Patrycja , Bombelli Silvia , Ramalingam Vernie , Purushotham Anand D , Pinder Sarah E , Dontu Gabriela
Published: May 2014

Introduction

Although estrogen and progesterone play a key role in normal mammary development and in breast cancer, the potential for proliferation and lineage differentiation as well as origin of cells that express the estrogen receptor (ER) in normal breast epithelium are not known. Some evidence suggests that normal human mammary stem/progenitor cells are ER–, but the identity of these cells and the cellular hierarchy of breast epithelium are still subjects of controversy. It is likely that elucidation of these aspects will bring insight into the cellular origin of breast cancer subtypes.

Methods

We used fluorescence-activated cell sorting of primary human mammary epithelial cells along with in vitro and in vivo functional assays to examine the hierarchic relation between cells with aldehyde dehydrogenase enzymatic activity (ALDH+ cells) and ER+ cells in the normal human breast epithelium. We assessed the proliferation and lineage differentiation potential of these cells in vitro and in vivo. A gene reporter assay was used to separate live ER+ and ER– mammary epithelial cells. With shRNA-mediated knockdown, we investigated the role of ALDH isoforms in the functionality of mammary epithelial progenitor cells.

Results

We describe a cellular hierarchy in the normal human mammary gland in which ER–/ALDH+ cells with functional properties of stem/progenitor cells generate ER+ progenitor cells, which in turn give rise to cells of luminal lineage. We show that the ALDH1A1 isoform, through its function in the retinoic acid metabolism, affects the proliferation and/or early differentiation of stem/progenitor cells and is important for branching morphogenesis.

Conclusions

This study presents direct evidence that ER+ cells are generated by ER–/ALDH+ stem/progenitor cells. We also show that ER+ cells are able to generate cell progeny of luminal lineage in vitro and in vivo. Loss of ALDH1A1 function impairs this process, as well as branching morphogenesis and clonogenicity in suspension culture. This latter effect is reversed by treatment with retinoic acid.
Current practice in the management of tetanus
Authors: Govindaraj Geeta M , Riyaz Arakkal
Published: May 2014

Tetanus is still a scourge among the under-privileged populations of the world, and unfortunately remains an important cause of death although a cheap, safe and highly efficacious vaccine is available. The rarity of the disease in some parts of the world results in newly trained physicians being unable to make a clinical diagnosis, and hampers the conduct of adequately powered randomized controlled trials. Several new and experimental pharmacological agents are being used to control the spasms in tetanus, and to combat the autonomic instability that occurs in the disease. New evidence is emerging regarding the use of antibiotics and intrathecal immunoglobulin in tetanus. It is imperative, therefore, that all physicians working in critical care should be aware of the current advances and evidence-based guidelines for management of tetanus in order to achieve the best outcomes, which Rodrigo and colleagues have reviewed in a recent issue of Critical Care.
Joint inversion of Rayleigh-wave dispersion and P-wave refraction data for laterally varying layered models
Authors: Boiero Daniele , Socco Laura Valentina
Published: May 2014

We implemented a joint inversion method to build P- and S-wave velocity models from Rayleigh-wave and P-wave refraction data, specifically designed to deal with laterally varying layered environments. A priori information available over the site and any physical law to link model parameters can be also incorporated. We tested and applied the algorithm behind the method. The results from a field data set revealed advantages with respect to individual surface-wave analysis (SWA) and body wave tomography (BWT). The algorithm imposed internal consistency for all the model parameters relaxing the required a priori assumptions (i.e., Poisson’s ratio level of confidence in SWA) and the inherent limitations of the two methods (i.e., velocity decreases for BWT).
Drowning (in) Kittens: The Reproduction of Girlhood in Victorian America
Authors: Barnes Elizabeth
Published: May 2014

Following Donna Haraway’s concept of the “killable” animal in When Species Meet, this essay looks at the social conditions and literary conventions that render ostensibly “priceless” objects, like pets and children, disposable in the Victorian period. Through the Victorian trope of the drowned kitten, Barnes shows how sentimental culture’s alternative “economy of feeling” colludes with, rather than opposes, a market economy chiefly concerned with reducing populations. The essay’s primary example is the female bildungsroman, where anxieties over female biological reproduction are obscured by the reproduction of an idea of the generic, iterable, and ultimately “killable” girl.
Nahua Cartography in Historical Context: Searching for Sources on the Mapa de Otumba
Authors: de la Paz María Castañeda
Published: May 2014

The Mapa de Otumba is a colonial map from central Mexico with pictographic elements that represents a part of the señorío (lordship) of Otumba with a number of its subject towns. An analytical problem of working with this document is a lack of an accompanying text, making it difficult to understand why it was made and by whom. However, using certain archival documents, it has been possible to explore the provenance of the map. In this essay, a new date for the production of the map is proposed, with a discussion of its function as a property register of land for the community of Otumba. Beyond these important issues, it has been possible to identify the use of lands and their control and transfer from one owner to another. Ethnographic fieldwork, a vital part of the research of such a document, facilitated the identification of many of the represented places in the present-day landscape, as such showing a historical-geographic register of land from the colonial period to the present.
Identification and characterization of putative stem cells in the adult pig ovary
Authors: Bui Hong-Thuy , Van Thuan Nguyen , Kwon Deug-Nam , Choi Yun-Jung , Kang Min-Hee , Han Jae-Woong , Kim Teoan , Kim Jin-Hoi
Published: May 2014

Recently, the concept of ‘neo-oogenesis’ has received increasing attention, since it was shown that adult mammals have a renewable source of eggs. The purpose of this study was to elucidate the origin of these eggs and to confirm whether neo-oogenesis continues throughout life in the ovaries of the adult mammal. Adult female pigs were utilized to isolate, identify and characterize, including their proliferation and differentiation capabilities, putative stem cells (PSCs) from the ovary. PSCs were found to comprise a heterogeneous population based on c-kit expression and cell size, and also express stem and germ cell markers. Analysis of PSC molecular progression during establishment showed that these cells undergo cytoplasmic-to-nuclear translocation of Oct4 in a manner reminiscent of gonadal primordial germ cells (PGCs). Hence, cells with the characteristics of early PGCs are present or are generated in the adult pig ovary. Furthermore, the in vitro establishment of porcine PSCs required the presence of ovarian cell-derived extracellular regulatory factors, which are also likely to direct stem cell niche interactions in vivo. In conclusion, the present work supports a crucial role for c-kit and kit ligand/stem cell factor in stimulating the growth, proliferation and nuclear reprogramming of porcine PSCs, and further suggests that porcine PSCs might be the culture equivalent of early PGCs.
Low-temperature Synthesis of (K0.5Na0.5)NbO3 Nanopowders by an Urea Sol–Gel Combustion Method
Authors: Van Nguyen Duc , Nhiem Dao Ngoc
Published: May 2014

Lead-free piezoelectric (K0.5Na0.5)NbO3 nanopowders were synthesized by urea sol–gel combustion method using freshly prepared Nb2O5·nH2O and alkali hydroxides as starting materials and urea as a fuel. The effects of metal cation/urea molar ratio and calcination temperature on the crystalline phase formation of (K0.5Na0.5)NbO3 were systematically investigated. The results showed that at a metal cation/urea molar ratio of 1:1, the single crystalline (K0.5Na0.5)NbO3 nanopowders, with an average grain size of 15 nm, were synthesized at calcination temperatures as low as 400 °C.
Moscow regional education cluster in tourism and service
Authors: Федулин Александр , Fedulin Aleksandr , Сахарчук Елена , Sakharchuk Elena
Published: May 2014

The article substantiates the relevance of a cluster model integrating the resources of those participating

in the system of personnel training for the Moscow region tourism and service industry with the view to

alleviating the personnel shortage and the inadequate professional training of the employees in the target

sphere of regional activity. The principle of continuous professional development based on the strategic

complex approach to the demand-for-personnel forecasting is used as the conceptual foundation for the

cluster formation. The authors propose a solution to the personnel issues concerning multisector spheres of

activity: 1) at the regional level; 2) on the intersectoral and interdepartmental basis. The authors describe the

efficiency factors of a cluster-model-based organization of professional training systems providing personnel

training fordifferent spheres of activity. Among these factors are: 1) regional and local authority’s engagement

in solving the staffing problems of the major sector; 2) a recognition by the administrative bodies, educational

establishments, business and society in general of the necessity to consider not only the narrow utility task

of vacancy-filling, but also, more importantly, the task of equipping the learners with valuable personality

tools potentially promoting effective socialization, professionalization, and continuous development through

common cultural, methodical and professional competence formation; 3) the readiness level of participants in

the system of professional training to take a systematic, purposeful and progressive perspective on developing the on-mid-and-long-term-demand training programmes: from professional induction at the initial stages of

learning to advanced training at graduate and postgraduate levels.
Business Analytics Assists Transitioning Traditional Medicine to Telemedicine at Virtual Radiologic
Authors: Körpeoğlu Ersin , Kurtz Zachary , Kılınç-Karzan Fatma , Kekre Sunder , Basu Pat A.
Published: May 2014

Virtual Radiologic (vRad), the largest teleradiology company in the United States, faces the difficult problem of matching more than 400 radiologists with time-varying and seasonal demand. In addition to the constraints that traditional medical facilities face, vRad is subject to supply and demand requirements that are unique to the teleradiology business environment. In this paper, we present a forecasting and capacity-planning model that more accurately assesses demand and plans system capacity to provide better service to vRad’s customers. We discuss the underlying reasons for improvement and quantify the impact on vRad’s entire system. We explain managerial insights that will help both vRad and other companies in the service sector with similar service-response requirements and demand patterns. We also highlight the implementation challenges our teams faced.
Add or Multiply? A Tutorial on Ranking and Choosing with Multiple Criteria
Authors: Tofallis Chris
Published: May 2014

Simple additive weighting is a well-known method for scoring and ranking alternative options based on multiple attributes. However, the pitfalls associated with this approach are not widely appreciated. For example, the apparently innocuous step of normalizing the various attribute data in order to obtain comparable figures leads to markedly different rankings depending on which normalization is chosen. When the criteria are aggregated using multiplication, such difficulties are avoided because normalization is no longer required. This removes an important source of subjectivity in the analysis because the analyst no longer has to make a choice of normalization type. Moreover, it also permits the modelling of more realistic preference behaviour, such as diminishing marginal utility, which simple additive weighting does not provide. The multiplicative approach also has advantages when aggregating the ratings of panel members. This method is not new but has been ignored for too long by both practitioners and teachers. We aim to present it in a nontechnical way and illustrate its use with data on business schools.
Possible or Probable? An Experiential Approach to Probability Literacy
Authors: McLaren Constance H. , McLaren Bruce J.
Published: May 2014

This paper presents the design for and results from an experiential learning activity for beginning statistics or decision analysis students. University students in a required business statistics class are given the task of asking subjects to rank 10 commonly heard uncertainty phrases (words such as “possible” and “probable”) in order from those that convey the most likelihood to those that indicate the least. The learning goals are communication, analysis of field results, and reflection upon the experience, and these are accomplished while exploring the concepts of subjective probability assessment as they are being learned in class. Students report their results and write a reflective report that covers their findings, the experience of working with participants, and, most importantly, their insights about language and the public's understanding of uncertainty. As students realize that those who assess probability are not always those who use the assessments for decision making, they become aware of the potential for confusion. The purpose of this article is not to conduct a statistical study of the rankings of the phrases, but rather to discuss the value of this experiential learning assignment for beginning students.
Case Article—Take Me Out Of The Ball Game
Authors: Pazgal Amit , Reinhardt Gilles
Published: May 2014

This paper describes a teaching case in which students model crowd management using process analysis. The case study consists of a classroom exercise that provides a practical illustration of the steps required to analyze a process, the need for abstraction in modeling a process, and an understanding of the relationship between process metrics and their managerial implications. The students are expected to behave as city planning consultants, addressing the long lines fans regularly face when getting home at the end of a Chicago Cubs™ baseball game. The case requires them to use knowledge from operations, economics, and process analysis classes to model, analyze and provide concrete solutions to alleviate crowding.

Case Teaching Note: Interested Instructors please see the Instructor Materials page for access to the restricted materials. To maintain the integrity and usefulness of cases published in ITE, unapproved distribution of the case teaching notes and other restricted materials to any other party is prohibited.
Puzzle—IP Satisfied
Authors: Chlond Martin J.
Published: May 2014

Finding a feasible as opposed to optimal solution of an integer program model comes under the heading of constraint programming and if a model is also a binary integer program (BIP) it is known to be equivalent to the satisfiability (SAT) problem from Boolean logic. Many of the puzzles treated in this column over the years and a host of others fall into this category, that is, they may be modeled purely using binary variables and the aim is to fulfil the conditions of the puzzle rather than to optimize a function. This leads to the possibility that there may be gains in efficiency to be found by looking beyond general IP solvers to more specialized programs.

The following article presents five puzzles together with IP formulations where the writer has experienced significant improvements in solution times using a SAT solver rather than a general purpose IP solver. The puzzles will be modeled and solved using three freely available open source packages, namely GLPK, Minisat and SCIP. GLPK and Minisat are both available in the GUSEK distribution from http://gusek.sourceforge.net/gusek.html and SCIP is available from http://scip.zib.de/ . GLPK is a general purpose linear and mixed integer solver, SCIP solves both Integer Programs and Constraint Programs and Minisat is exclusively an SAT solver. The GUSEK environment provides direct access to GLPK and Minisat. It also has the option to generate MPS formatted files of Mathprog models which may be read into SCIP and solved.
Optimal Credit Swap Portfolios
Authors: Giesecke Kay , Kim Baeho , Kim Jack , Tsoukalas Gerry
Published: May 2014

This paper formulates and solves the selection problem for a portfolio of credit swaps. The problem is cast as a goal program that entails a constrained optimization of preference-weighted moments of the portfolio value at the investment horizon. The portfolio value takes account of the exact timing of protection premium and default loss payments, as well as any mark-to-market profits and losses realized at the horizon. The constraints address collateral and solvency requirements, initial capital, position limits, and other trading constraints that credit swap investors often face in practice. The multimoment formulation accommodates the complex distribution of the portfolio value, which is a nested expectation under risk-neutral and actual probabilities. It also generates computational tractability. Numerical results illustrate the features of optimal portfolios. In particular, we find that credit swap investment constraints can have a significant impact on optimal portfolios, even for simple investment objectives. Our problem formulation and solution approach extend to corporate bond portfolios and mixed portfolios of corporate bonds and credit derivatives.

This paper was accepted by Wei Xiong, finance.
Comparison of juvenile and adult onset systemic lupus erythematosus
Authors: Baqai Tanya , Ioannou Yiannis
Published: May 2014

Systemic lupus erythematosus is a multisystem autoimmune disease of unknown aetiology, described as juvenile systemic lupus erythematosus if the onset is before 16–18 years of age. This review outlines current understanding of juvenile systemic lupus erythematosus and differences between this and adult onset disease.
Inpatient glucocorticoid use: beneficence vs non-maleficence
Authors: Dhatariya Ketan
Published: May 2014

Data suggest that over 12% of inpatients are taking high-dose glucocorticoids, which are a well-recognized cause of hyperglycaemia. Hyperglycaemia is associated with poor outcomes in most medical and surgical specialities, yet rates of blood glucose monitoring and appropriate management remain very low.
Day-case tonsillectomy: is the NHS demanding unobtainable targets?
Authors: Trinidade A , Phillips JS , Bath AP
Published: May 2014

In its 2002 document Delivering the NHS Plan, the Department of Health set a target of 75% of all surgical procedures being performed as day-case procedures. 1 Tonsillectomy is quoted as one of the operations in the ‘basket’ of 25 procedures deemed suitable by the Audit Commission and the British Association of Day Surgery (BADS). 2 , 3 With respect to tonsillectomy alone, the target is quoted as 70% for children and 80% for adults. 3
Trends in surgical litigation claims
Authors: Mead John
Published: May 2014

Civil claims against NHS bodies in England arising from the actions or inaction of surgeons have risen by 66% in 5 years owing to the funding system in place prior to 1 April 2013. Orthopaedics accounts for the largest percentage of claims. The basic legal test (Bolam) has been in place since the late 1950s and has been amended only slightly by Bolitho in 1997.
An Updated Guide to Study Polyandry in Social Insects
Authors: Jaffé Rodolfo
Published: May 2014

In spite of the importance of understanding the adaptive significance of polyandry in the social Hymenoptera (ants, bees and wasps), little consensus exists regarding the terminology employed, the use of different paternity estimates, the calculation of such estimates and their associated error measures, and the way paternity should be treated in comparative studies. Here I summarize previous methodological contributions to the study of polyandry in social insects, hoping that such a compendium will serve as an updated guide to future researchers. I first revise the estimates describing queen mating behavior and paternity outcomes in polyandrous social insects, outlining appropriate methods for calculating them. I then address the errors associated to paternity estimates and explain how to account for them. Finally I discuss in which cases paternity should be treated as a continuous or a categorical variable, and provide an insight into the distribution of paternity across the social Hymenoptera. This technical review highlights the importance of standardizing research methods to prevent common errors, raise confidence in the reported data, and facilitate comparisons between studies, to help shed light into many unanswered questions.
Trophic Guild Structure of a Canopy Ants Community in a Mexican Tropical Deciduous Forest
Authors: Castaño-Meneses Gabriela
Published: May 2014

Ants constitute a very important element in the canopies of tropical forest. The species richness, composition and diversity of ant canopy community in a tropical deciduous forest in the Pacific Cost of Mexico was studied. The sampling was performed by fogging method in a watershed of the Chamela Biological Station, Jalisco State, Mexico. Ants represented 0.5% of all invertebrates in the tree canopy of Chamela, and a total of 46 ant morphospecies from 17 genera were collected. Camponotus and Cephalotes contributed with 13 and 6 species respectively, and the most abundant ants were species of Crematogaster, Tapinoma, Cephalotes and Camponotus. Ant composition was broadly similar at the two sites, and on different canopy species, although significant differences in abundance were apparent for some individual ant species. The dominant guild in the canopy was the omnivourous in all study, but differences in guild trophic composition were recorded in each fogging. The ant community in the canopy of Chamela has shown low spatial variation, but the composition of ant species and trophic guilds have important seasonal variations, demonstrated variations in the exploitation of resources along the year, and vertical migrations of ant species from soil and shrub layer to canopy in the tropical deciduous forest.
Studies on an Enigmatic Blepharidatta Wheeler Population (Hymenoptera: Formicidae) from the Brazilian Caatinga
Authors: Pereira Janaina Cruz , Delabie Jacques Hubert Charles , Zanette Lorenzo Roberto Sgobaro , Quinet Yves Patric
Published: May 2014

Blepharidatta is a rare Neotropical ant genus formed by predatory species whose small colonies nest in soil or leaf-litter. A population of Blepharidatta that presents affinities with the Cerrado species, Blepharidatta conops Kempf, was found in the Caatinga biome, at the “Reserva Particular do Patrimônio Natural Serra das Almas” (RPPNSA), in Crateús (State of Ceará, northeastern Brazil). The aim of our study was to obtain information on nest architecture, size and composition of colonies, foraging behavior, and female castes morphology in this newly found population, and to compare it with other Blepharidatta species, particularly B. conops. The results show that Blepharidatta sp. and B. conops share key features of their biology like basic nest architecture, diet and foraging behavior, monogyny, and ergatoid queens with a phragmotic head. However, marked differences were also found in queen head and mesosoma morphology, nest architecture, colony size, and queen location in the nest. Two mutually exclusive hypotheses are discussed. The Blepharidatta population found in the RPPNSA would represent a new species, possibly endemic to the Caatinga biome or this population would represent one extreme of the phenotypic variations observed in populations forming B. conops species.
The zero lower bound: frequency, duration, and numerical convergence
Authors: Richter Alexander W. , Throckmorton Nathaniel A.
Published: May 2014

When monetary policy faces a zero lower bound (ZLB) constraint on the nominal interest rate, a minimum state variable (MSV) solution may not exist even if the Taylor principle holds when the ZLB does not bind. This paper shows there is a clear tradeoff between the expected frequency and average duration of ZLB events along the boundary of the convergence region – the region of the parameter space where our policy function iteration algorithm converges to an MSV solution. We show this tradeoff with two alternative stochastic processes: one where monetary policy follows a 2-state Markov chain, which exogenously governs whether the ZLB binds, and the other where ZLB events are endogenous due to discount factor or technology shocks. We also show that small changes in the parameters of the stochastic processes cause meaningful differences in the decision rules and where the ZLB binds in the state space.
Preparation of Oxidized Starch Using Environment Friendly Chlorine Dioxide as Oxidant
Authors: Guo Jintang , Huang Yancui , Zhang Jin , Yin Junwei
Published: May 2014

In the present work, the oxidized corn starch was prepared by using chlorine dioxide as novel oxidant. It was characterized by X-ray diffraction, scanning electron microscope (SEM), and transmission electron microscope (TEM). The main factors that affect the oxidation process were studied, and the oxidation degree of oxidized starch was determined by the carboxyl content and viscosity of the product. The results show that carboxyl groups are introduced into the starch chains successfully, and the oxidation reaction mainly carries out at the amorphous area. Compared with native starch, the light transmittance and anti-retrogradation of oxidized starch increase, whereas the viscosity reduces. The best oxidized starch can be obtained at the sodium chlorate dosage of 3%, hydrochloric acid 4%, and sulfuric acid 3% (all based on the initial starch weight), while the oxidation reaction is conducted at 50°C for 5 h.
Learning motor skills: from algorithms to robot experiments
Authors: Kober Jens
Published: May 2014

In this thesis, we discuss approaches that allow robots to learn motor
skills. Motor skills can often be represented by motor primitives,
which encode elemental motions. To date, there have been a number
of successful applications of learning motor primitives employing
imitation learning. However, many interesting motor learning problems
are high-dimensional reinforcement learning problems which are often
beyond the reach of current reinforcement learning methods. This thesis
contributes to the state of the art in reinforcement learning applied
to robotics both in terms of novel algorithms and applications. We
show how motor primitives can be employed to learn motor skills on
three different levels. All proposed approaches have been extensively
validated with tasks such as Ball-in-a-Cup, darts, table tennis, ball
throwing, or ball bouncing both in simulation, and on real robots.