bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation of Se (0) Nanoparticles by Duganella sp. and Agrobacterium sp. isolated from Se-laden soil of North-East Punjab, India
Authors: Bajaj Mini , Schmidt Susan , Winter Josef
Published: May 2012

Background

Selenium (Se) is an essential trace element, but is toxic at high concentrations. Depending upon the geological background, the land use or on anthropogenic pollution, different amounts of Se may be present in soil. Its toxicity is related to the oxyanions selenate and selenite as they are water soluble and bioavailable. Microorganisms play an important role in Se transformations in soil and its cycling in the environment by transforming water-soluble oxyanions into water insoluble, non-toxic elemental Se (0). For this study, soil samples were collected from selenium-contaminated agricultural soils of Punjab/India to enrich and isolate microbes that interacted with the Se cycle.

Results

A mixed microbial culture enriched from the arable soil of Punjab could reduce 230 mg/l of water soluble selenite to spherical Se (0) nanoparticles during aerobic growth as confirmed by SEM-EDX. Four pure cultures (C 1, C 4, C 6, C 7) of Gram negative, oxidase and catalase positive, aerobic bacteria were isolated from this mixed microbial consortium and identified by 16 S rDNA gene sequence alignment as two strains of Duganella sp. (C 1, C 4) and two strains of Agrobacterium sp.(C 6, C 7). SEM/TEM-EDX analyses of the culture broth of the four strains revealed excretion of uniformly round sharply contoured Se (0) nanoparticles by all cultures. Their size ranged from 140–200 nm in cultures of strains C 1 and C 4, and from 185–190 nm in cultures of strains C 6 and C 7. Both Duganella sp. revealed better selenite reduction efficiencies than the two Agrobacterium sp.

Conclusions

This is the first study reporting the capability of newly isolated, aerobically growing Duganella sp. and Agrobacterium sp. from soils of Punjab/India to form spherical, regularly formed Se (0) nanoparticles from water soluble selenite. Among others, the four strains may significantly contribute to the biogeochemical cycling of Se in soil. Bioconversion of toxic selenite to non-toxic Se (0) nanoparticles under aerobic conditions in general may be useful for detoxification of agricultural soil, since elemental Se may not be taken up by the roots of plants and thus allow non-dangerous fodder and food production on Se-containing soil.
Encapsulation of Alpha-1 antitrypsin in PLGA nanoparticles: In Vitro characterization as an effective aerosol formulation in pulmonary diseases
Authors: Pirooznia Nazanin , Hasannia Sadegh , Lotfi Abbas Sahebghadam , Ghanei Mostafa
Published: May 2012

Background

Alpha 1- antitrypsin (α1AT) belongs to the superfamily of serpins and inhibits different proteases. α1AT protects the lung from cellular inflammatory enzymes. In the absence of α1AT, the degradation of lung tissue results to pulmonary complications. The pulmonary route is a potent noninvasive route for systemic and local delivery. The aerosolized α1AT not only affects locally its main site of action but also avoids remaining in circulation for a long period of time in peripheral blood. Poly (D, L lactide-co glycolide) (PLGA) is a biodegradable and biocompatible polymer approved for sustained controlled release of peptides and proteins. The aim of this work was to prepare a wide range of particle size as a carrier of protein-loaded nanoparticles to deposit in different parts of the respiratory system especially in the deep lung. Various lactide to glycolide ratio of the copolymer was used to obtain different release profile of the drug which covers extended and rapid drug release in one formulation.

Results

Nonaqueous and double emulsion techniques were applied for the synthesis of nanoparticles. Nanoparticles were characterized in terms of surface morphology, size distribution, powder X-ray diffraction (XRD), encapsulation efficiency, in vitro drug release, FTIR spectroscopy and differential scanning calorimetry (DSC). To evaluate the nanoparticles cytotoxicity, cell cytotoxicity test was carried out on the Cor L105 human epithelial lung cancer cell line.

Nanoparticles were spherical with an average size in the range of 100 nm to 1μ. The encapsulation efficiency was found to be higher when the double emulsion technique was applied. XRD and DSC results indicated that α1AT encapsulated in the nanoparticles existed in an amorphous or disordered-crystalline status in the polymer matrix. The lactic acid to glycolic acid ratio affects the release profile of α1AT. Hence, PLGA with a 50:50 ratios exhibited the ability to release %60 of the drug within 8, but the polymer with a ratio of 75:25 had a continuous and longer release profile. Cytotoxicity studies showed that nanoparticles do not affect cell growth and were not toxic to cells.

Conclusion

In summary, α1AT-loaded nanoparticles may be considered as a novel formulation for efficient treatment of many pulmonary diseases.
Clinical, haematological and biochemical responses of sheep undergoing autologous blood transfusion
Authors: Sousa Rejane Santos , Chaves Dowglish Ferreira , Barrêto-Júnior Raimundo Alves , Sousa Isadora Karolina Freitas , Soares Herbert Sousa , Barros Isabella Oliveira , Minervino Antonio Humberto Hamad , Ortolani Enrico Lippi
Published: May 2012

Background

This study aimed to evaluate the clinical, haematological and biochemical responses to autologous blood transfusion and the feasibility of this practice in sheep. Thus, we used eight male, 8 months old sheep, weighing on average 30 kg, from which 15 mL/kg of whole blood was collected and stored in CPDA-1 bags. Blood samples were refrigerated for 8 days and subsequently re-infused. The clinical, haematological and biochemical parameters were evaluated before blood collection and reinfusion, after 10 minutes of collection and reinfusion, after 3, 6, 12, 24, 48, 96 and 192 hours after collection and reinfusion.

Results

With respect to clinical parameters, we observed a decrease in heart rate after 24, 48 and 196 hours from reinfusion compared to basal values (p < 0.05). Haematological variables including globular volume and erythrocyte counts showed a significant decrease (p < 0.01) at all time points after collection and increased (p < 0.01) at all time points after reinfusion. There was a significant increase in total protein and calcium at all time points after reinfusion (p < 0.05).

Conclusion

Autologous transfusion in sheep slightly altered the physiological, biochemical and haematological responses of sheep, indicating that the technique proposed is safe and can be applied in the clinical practice of this species. The 8 d period was not sufficient for complete recovery of the haematological parameters after blood collection.
Modeling of human factor Va inactivation by activated protein C
Authors: Bravo Maria Cristina , Orfeo Thomas , Mann Kenneth G , Everse Stephen J
Published: May 2012

Background

Because understanding of the inventory, connectivity and dynamics of the components characterizing the process of coagulation is relatively mature, it has become an attractive target for physiochemical modeling. Such models can potentially improve the design of therapeutics. The prothrombinase complex (composed of the protease factor (F)Xa and its cofactor FVa) plays a central role in this network as the main producer of thrombin, which catalyses both the activation of platelets and the conversion of fibrinogen to fibrin, the main substances of a clot. A key negative feedback loop that prevents clot propagation beyond the site of injury is the thrombin-dependent generation of activated protein C (APC), an enzyme that inactivates FVa, thus neutralizing the prothrombinase complex. APC inactivation of FVa is complex, involving the production of partially active intermediates and “protection” of FVa from APC by both FXa and prothrombin. An empirically validated mathematical model of this process would be useful in advancing the predictive capacity of comprehensive models of coagulation.

Results

A model of human APC inactivation of prothrombinase was constructed in a stepwise fashion by analyzing time courses of FVa inactivation in empirical reaction systems with increasing number of interacting components and generating corresponding model constructs of each reaction system. Reaction mechanisms, rate constants and equilibrium constants informing these model constructs were initially derived from various research groups reporting on APC inactivation of FVa in isolation, or in the presence of FXa or prothrombin. Model predictions were assessed against empirical data measuring the appearance and disappearance of multiple FVa degradation intermediates as well as prothrombinase activity changes, with plasma proteins derived from multiple preparations. Our work integrates previously published findings and through the cooperative analysis of in vitro experiments and mathematical constructs we are able to produce a final validated model that includes 24 chemical reactions and interactions with 14 unique rate constants which describe the flux in concentrations of 24 species.

Conclusion

This study highlights the complexity of the inactivation process and provides a module of equations describing the Protein C pathway that can be integrated into existing comprehensive mathematical models describing tissue factor initiated coagulation.
Trapping of Rift Valley Fever (RVF) vectors using Light Emitting Diode (LED) CDC traps in two arboviral disease hot spots in Kenya
Authors: Tchouassi David P , Sang Rosemary , Sole Catherine L , Bastos Armanda DS , Cohnstaedt Lee W , Torto Baldwyn
Published: May 2012

Background

Mosquitoes’ response to artificial lights including color has been exploited in trap designs for improved sampling of mosquito vectors. Earlier studies suggest that mosquitoes are attracted to specific wavelengths of light and thus the need to refine techniques to increase mosquito captures following the development of super-bright light-emitting diodes (LEDs) which emit narrow wavelengths of light or very specific colors. Therefore, we investigated if LEDs can be effective substitutes for incandescent lamps used in CDC light traps for mosquito surveillance, and if so, determine the best color for attraction of important Rift Valley Fever (RFV) vectors.

Methods

The efficiency of selected colored LED CDC light traps (red, green, blue, violet, combination of blue-green-red (BGR)) to sample RVF vectors was evaluated relative to incandescent light (as control) in a CDC light trap in two RVF hotspots (Marigat and Ijara districts) in Kenya. In field experiments, traps were baited with dry ice and captures evaluated for Aedes tricholabis, Ae. mcintoshi, Ae. ochraceus, Mansonia uniformis, Mn. africana and Culex pipiens, following Latin square design with days as replicates. Daily mosquito counts per treatment were analyzed using a generalized linear model with Negative Binomial error structure and log link using R. The incidence rate ratios (IRR) that mosquito species chose other treatments instead of the control, were estimated.

Results

Seasonal preference of Ae.mcintoshi and Ae. ochraceus at Ijara was evident with a bias towards BGR and blue traps respectively in one trapping period but this pattern waned during another period at same site with significantly low numbers recorded in all colored traps except blue relative to the control. Overall results showed that higher captures of all species were recorded in control traps compared to the other LED traps (IRR < 1) although only significantly different from red and violet.

Conclusion

Based on our trapping design and color, none of the LEDs outcompeted the standard incandescent light. The data however provides preliminary evidence that a preference might exist for some of these mosquito species based on observed differential attraction to these light colors requiring future studies to compare reflected versus transmitted light and the incorporation of colored light of varying intensities.
Population genetic structure of Ascaridia galli re-emerging in non-caged laying hens
Authors: Höglund Johan , Morrison David A , Engström Annie , Nejsum Peter , Jansson Désirée S
Published: May 2012

Background

The poultry roundworm Ascaridia galli has reappeared in hens kept for egg production in Sweden after having been almost absent a decade ago. Today this is a frequent intestinal nematode parasite in non-caged laying hens. The aim of this study was to investigate the genetic diversity (Fst) in A. galli collected from different poultry production sites in southern Sweden, to identify possible common routes of colonization.

Methods

Adult parasites (n = 153) from 10 farms, including both broiler breeder parents and laying hens, were investigated by amplified restriction fragment length polymorphism analysis (AFLP). Worms from a Danish laying hen farm were also included for comparison. Most of the farms were represented by worms from a single host, but on two farms multiple samples from different hosts were assessed in order to study flock variation.

Results

A total of 97 fragments (loci) were amplified among which 81% were variable alleles. The average genetic diversity was 0.13 (range = 0.09-0.38), which is comparable to other AFLP studies on nematodes of human and veterinary importance. Within-farm variation showed that worms harboured by a single hen in a flock covered most of the A. galli genetic variation within the same flock (Fst = 0.01 and 0.03 for two farms). Between-farm analysis showed a moderate population genetic structure (Fst = 0.13), along with a low mutational rate but high gene flow between different farms, and absence of strong genetic selection. Network analysis showed repeated genetic patterns among the farms, with most worms on each farm clustering together as supported by high re-allocation rates.

Conclusions

The investigated A. galli populations were not strongly differentiated, indicating that they have undergone a genetic bottlenecking and subsequent drift. This supports the view that the investigated farms have been recently colonized, and that new flocks are reinfected upon arrival with a stationary infection.
Prevalence of Delayed Nausea and/or Vomiting in Patients Treated With Oxaliplatin-Based Regimens for Colorectal Cancer
Authors: Fleishman Stewart B. , Mahajan Divya , Rosenwald Victoria , Nugent Ann V. , Mirzoyev Tahir
Published: May 2012

Factors associated with nausea after oxaliplatin-based chemotherapy are intrinsic to the patient and mostly unrelated to the antiemetics used.
Effects of Funding Policy Changes and Health Warnings on the Use of Erythropoiesis-Stimulating Agents
Authors: Weir Matthew A. , Gomes Tara , Winquist Eric , Juurlink David N. , Cuerden Meaghan S. , Mamdani Muhammad
Published: May 2012

Formulary access and safety warnings had significant impacts on the new use of ESAs in patients with cancer, suggesting that both are effective means of influencing the use of these drugs.
Less Than Ideal: How Oncologists Practice With Limited Drug Access
Authors: Chan Kelvin K. , Wong Bertha , Siu Lillian L. , Straus Sharon E. , Chang José , Berry Scott R.
Published: May 2012

Canadian medical oncologists are struggling to provide optimal care for their patients with metastatic colorectal cancer as a result of differential access to preferred therapeutic drugs.
Effects of Vaginal Estrogens on Serum Estradiol Levels in Postmenopausal Breast Cancer Survivors and Women at Risk of Breast Cancer Taking an Aromatase Inhibitor or a Selective Estrogen Receptor Modulator
Authors: Wills Shannon , Ravipati Anita , Venuturumilli Padmaja , Kresge Cynthia , Folkerd Elizabeth , Dowsett Mitch , Hayes Daniel F. , Decker David A.
Published: May 2012

The authors conclude that intravaginal estradiol treatment, regardless of type, results in elevated circulating E2 levels in this population and should be used with caution.
Trends in Twitter Use by Physicians at the American Society of Clinical Oncology Annual Meeting, 2010 and 2011
Authors: Chaudhry Aafia , Glodé L. Michael , Gillman Matt , Miller Robert S.
Published: May 2012

Despite the 140-character limit, Twitter was used by physicians at the 2010 and 2011 ASCO Annual Meetings to engage in clinical discussions, whether or not an author was on site as a live attendee.
Visit Duration for Outpatient Physician Office Visits Among Patients With Cancer
Authors: Guy Gery P. , Richardson Lisa C.
Published: May 2012

Higher use of performance-based payment mechanisms and capitated arrangements are associated with a decrease in the amount of time physicians spend with patients with cancer.
Influence of Patient Preferences on the Cost-Effectiveness of Screening for Lynch Syndrome
Authors: Wang Grace , Kuppermann Miriam , Kim Benjamin , Phillips Kathryn A. , Ladabaum Uri
Published: May 2012

This cost-utility analysis reports on the effect of quality of life on the value of screening all new patients with colorectal cancer for Lynch syndrome.
Beyond Altruism? Economics and the Minimization of Unselfish Behavior, 1975–93
Authors: Fontaine Philippe
Published: May 2012

This article provides a historical account of the developments of research into seemingly unselfish behavior between 1975 and 1993. I shall first argue that the triumph of the self-interest model in the examination of seemingly unselfish behavior can better be understood if it is remembered that the attempts by a handful of economists to expand their jurisdiction over phenomena that had remained outside their reach occurred at a time when natural scientists showed similar ambitions. As those economists' efforts found a more receptive audience within the profession, disputes shifted, within the discipline itself, to the public policy implications of seemingly unselfish behavior. Then I shall argue that the various efforts to go beyond the self-interest model in economics and political science failed to build a coherent alternative model and produced equally ambiguous policy implications. My conclusion stresses the difficulty of escaping the customary presupposition that seemingly unselfish behavior concerns close-knit groups whereas selfishness applies to impersonal gatherings.
Advertising Ephemera and the Angel of History
Authors: Barlow Tani
Published: May 2012

This essay addresses a crucial object world of modern urban China, commodity advertising. It shows how attention to advertisements requires forceful wresting of images out of linear time. That the ads are themselves illustrations of linear time in popular narratives of modern history makes them complex. Plastered on billboards, placards, news kiosks, and trolleys; advertising Sun-Maid Raisins, Ford Model Ts, Pond's, Cutex products, cigarette brands, and Brunner Mond chemical fertilizer; and ubiquitous to all forms of media; the modern Chinese advertisement is a picture of and story about the industrially produced commodity and its explosive value to “society” as such. The evidence of advanced Chinese advertising markets in the interwar years 1919–37 allows contemporary historians to see “society” or “the social” as it was first theorized, the social as the sine qua non of modernity. Advertising objectifies the social. Thus while enlightened social theory in Chinese advertising markets is a phenomenon noted here in great detail, the point is that “society” underlies modernist theory as such. The discovery of the social in philosophy and in the dialectical advertising image in the interwar years offers up a possibility of critique. The central question historians can address and struggle over is What social formation does modern commodity culture support? The dialectical image is not referential, so it does not determine social forms. Rather, it proffers conditions in which possibilities perdure. If modern commodity culture supports restoration, then what sort of neotraditionalism appears in the social? If revolution, then what sorts of revolution?
Positioning positions in the Writing to the Future
Authors: Tolentino Rolando B.
Published: May 2012

The article maps out a political place for positions based on the idea of “writing to the future” or a political wager on the future precisely because of the valences of failure in the present. Using Alain Badiou's idea of truth and the state, and citing the conditions in the Philippines, the academic discourse has shifted from critique of to collaboration with the state. The article then draws from the cultural production of independent digital cinema—representing the most abject of subaltern identities and conditions—to show the limits and possibilities of wagering on the future.
Positioning Asia in a Global Future? An Example through Rethinking Finance
Authors: Song Jesook
Published: May 2012

As a response to positions' twentieth-anniversary workshop that solicited suggestions on the future direction of the journal, this article raises questions on how to study Asia without falling into traps of reproducing capitalist discourse that reduces the significance of Asia to its economic value. By contextualizing ways in which Asia is commodified as a promise to the global future at the same time it is chastised as yet to be civilized for the market economy, the article urges the investigation of the history of financialization in Asia as a window of rethinking “global” history of capitalism for challenging oversimplified imagination of the trajectory of finance capital and “global financial crisis.”
Queer positions, Queering Asian Studies
Authors: Rofel Lisa
Published: May 2012

What does it mean to say that positions opened up a space for queer intellectual work? How do we delineate that space? How does this space work in articulation with queering Asian studies more broadly? This essay addresses how the journal positions created the intellectual space for a queer Marxism within Asian studies. The journal enabled scholars to bring together questions of desire with critiques of capitalism and of racialized geopolitics.
Asian Boundaries, Documentary Regimes, and the Political Economy of the Personal
Authors: Chen Tina Mai
Published: May 2012

This article inquires into how “the personal” assumes specific positions relative to truth claims constitutive of twentieth-century national and international documentary systems. It analyzes migration of those identified as Chinese in and out of Burma during the late 1930s and 1940s. The focus is on how individuals, networks of people, and institutions presented and relied on information about families, physical appearance, personal interviews, and affective ties to make sense of migratory patterns resulting from Japanese military expansion.

The article argues that by the mid-1940s a layered inscription of citizenship, loyalty, and labor via “the personal” formed the basic structure of meaning mobilized in identification documents. It traces the specific ways in which this emerged around practices and policies developed to monitor and control Chinese migration within the Burma-China-India nexus. These structures not only prescribed particular evidentiary standards regarding personal interactions and signifiers that became part of national and international norms, but they also created hierarchies of affect and emotional attachment deemed appropriate for particular groupings of people, spatial designations, and material exchanges.

The focus on the personal is part of an effort to continue interrogation of Asia and its constitution as object of knowledge and lived experience in the past, present, and future. This article attends to the “the personal” as a site of potentiality to be analyzed historically as well as opened up through a continuous rethinking of Asia and the racialized relationship among nationality, state, and international orders.
“A Relentlessly Productive Venue”: Interview with Senior Editor, Tani Barlow
Authors: Karl Rebecca , Lamarre Tom , Pozzana Claudia , Russo Alessandro , Sakai Naoki , Song Jesook , Zito Angela
Published: May 2012

Rebecca Karl, Tom Lamarre, Claudia Pozzana, Alessandro Russo, Naoki Sakai, Jesook Song, and Angela Zito interview Senior Editor Tani Barlow, posing a series of question on history, politics, confiict, Cold War scholarship, and the struggle over so-called area studies. Topics raised and considered include the history of the journal's founding, critical reminiscence of the project's early years of publications and intellectual politics, historical trends in knowledge production and ways that the positions project has instigated pedagogic change, the contentious idea of “theory” in scholarship, and on editorial work and its relation to philosophy of history. The relation of the editor, her theory and practice of editing, and her relation to intellectual political history are explored at length.
Restructured endoplasmic reticulum generated by mutant amyotrophic lateral sclerosis-linked VAPB is cleared by the proteasome
Authors: Papiani Giulia , Ruggiano Annamaria , Fossati Matteo , Raimondi Andrea , Bertoni Giovanni , Francolini Maura , Benfante Roberta , Navone Francesca , Borgese Nica
Published: May 2012

VAPB (vesicle-associated membrane protein-associated protein B) is a ubiquitously expressed, ER-resident tail-anchored protein that functions as adaptor for lipid-exchange proteins. Its mutant form, P56S-VAPB, is linked to a dominantly inherited form of amyotrophic lateral sclerosis (ALS8). P56S-VAPB forms intracellular inclusions, whose role in ALS pathogenesis has not yet been elucidated. We recently demonstrated that these inclusions are formed by profoundly remodelled stacked ER cisternae. Here, we used stable HeLa-TetOff cell lines inducibly expressing wild-type VAPB and P56S-VAPB, as well as microinjection protocols in non-transfected cells, to investigate the dynamics of inclusion generation and degradation. Shortly after synthesis, the mutant protein forms small, polyubiquitinated clusters, which then congregate in the juxtanuclear region independently of the integrity of the microtubule cytoskeleton. The rate of degradation of the aggregated mutant is higher than that of the wild-type protein, so that the inclusions are cleared only a few hours after cessation of P56S-VAPB synthesis. At variance with other inclusion bodies linked to neurodegenerative diseases, clearance of P56S-VAPB inclusions involves the proteasome, with no apparent participation of macro-autophagy. Transfection of a dominant-negative form of the AAA ATPase p97/VCP stabilizes mutant VAPB, suggesting a role for this ATPase in extracting the aggregated protein from the inclusions. Our results demonstrate that the structures induced by P56S-VAPB stand apart from other inclusion bodies, both in the mechanism of their genesis and of their clearance from the cell, with possible implications for the pathogenic mechanism of the mutant protein.
Supply-Side Story: Risks, Guarantees, Competition, and Information Asymmetry
Authors: Gümüş Mehmet , Ray Saibal , Gurnani Haresh
Published: May 2012

The risk of supply disruption increases as firms seek to procure from cheaper, but unproven, suppliers. We model a supply chain consisting of a single buyer and two suppliers, both of which compete for the buyer's order and face risk of supply disruption. One supplier is comparatively more reliable but also more expensive, whereas the other one is less reliable but cheaper and faces higher risk of disruption. Moreover, the risk level of the unreliable supplier may be private information, and this lack of visibility increases the buyer's purchasing risk. In such settings, the unreliable supplier often provides a price and quantity (P&Q) guarantee to the buyer. Our objective is to study the underlying motivation for the guarantee offer and its effects on the competitive intensity and the performance of the chain partners. Our model also includes a spot market that can be utilized by any party to buy or to sell. The spot market price is random, partially depends on the available capacity of the two suppliers, and has a positive spread between buying and selling prices. We analytically characterize the equilibrium contracts for the two suppliers and the buyer's optimal procurement strategy. First, our analysis shows that P&Q guarantee allows the unreliable supplier to better compete against the more reliable one by providing supply assurance to the buyer. More importantly, when information asymmetry risk is high, use of a guarantee may enable the unreliable supplier to credibly signal her true risk, thereby improving visibility into the chain. This signal can also be used by the buyer to infer the expected spot market price. In spite of these benefits, a guarantee offer in an asymmetric setting may not always be desirable for the buyer. Rather, it can reduce competition between the suppliers, resulting in higher costs for the buyer.

This paper was accepted by Martin Lariviere, operations management.
Combining Equity and Utilitarianism in a Mathematical Programming Model
Authors: Hooker J. N. , Williams H. P.
Published: May 2012

We discuss the problem of combining the conflicting objectives of equity and utilitarianism, for social policy making, in a single mathematical programming model. The definition of equity we use is the Rawlsian one of maximizing the minimum utility over individuals or classes of individuals. However, when the disparity of utility becomes too great, the objective becomes progressively utilitarian. Such a model is particularly applicable not only to health provision but to other areas as well. Building a mixed-integer/linear programming (MILP) formulation of the problem raises technical issues, because the objective function is nonconvex and the hypograph is not MILP representable in its initial form. We present a succinct formulation and show that it is “sharp” in the sense that its linear programming relaxation describes the convex hull of the feasible set (before extra resource allocation or policy constraints are added). We apply the formulation to a healthcare planning problem and show that instances of realistic size are easily solved by standard MILP software.

This paper was accepted by Dimitris Bertsimas, optimization.
The Value of Product Variety When Selling to Strategic Consumers
Authors: Parlaktürk Ali K.
Published: May 2012

We consider a firm that sells two vertically (quality) differentiated products to strategically forward-looking consumers over two periods, setting the prices dynamically in each period. The consumers are heterogeneous in their evaluations of quality, and strategic in that they decide not only whether and which product variant to buy, but also when to buy, choosing the option that maximizes their utility. We derive the equilibrium of the pricing-purchasing game between the firm and the consumers. We find that the loss due to strategic customer behavior can be less with two product variants compared to the single-product benchmark, which indicates that product variety can serve as a lever when dealing with strategic customers. This benefit exists when the additional product has an inferior cost-to-quality ratio. Because of this benefit, a firm may find it attractive to sell a product variant that would be unprofitable otherwise. However, product variety can also hurt profitability due to strategic customer behavior: A product variant that would be profitable absent strategic customers can in fact be unprofitable. This can happen when customer impatience and firm costs are moderate.
Repatriating the GED: Urban youth and the alternative to a high school diploma
Authors: Tuck Eve
Published: May 2012

This article discusses competing perspectives on the value of the General Educational Development (GED) credential. Although scholars and journalists debate the worth of the credential, urban youth continue to pursue the GED, especially as proxy for inadequate schooling. Using qualitative data from a participatory action research project, the author appraises the value of the GED from the perspectives of urban youth, and argues that youth place significance in the credential in ways previously ignored and under theorized by educational researchers, practitioners, and policymakers.
The Development of an Adolescent Perception of Being Known Measure
Authors: Wallace Tanner LeBaron , Ye Feifei , McHugh Rebecca , Chhuon Vichet
Published: May 2012

Adopting a constructivist perspective of adolescent development, we argue adolescents' perceptions of being known reflect teachers' authentic recognition of adolescents' multiple emerging identities. As such, adolescent perceptions of being known are a distinct factor associated with high school students' engagement in school. A mixed method approach (Phase 1 focus groups, N = 72 , Phase 2 cross sectional survey, N = 890 ) guided the development and testing of an Adolescent Perception of Being Known Scale (A-PBKS). Here, we report on item development, item performance, convergent, divergent, and predictive validity as well as measurement invariance. We conclude the paper by outlining the promise research studying instructional moves through a developmental lens has for understanding teaching and learning in urban high schools.
Mexico City's Symbolic Geography: The Processions of Our Lady of Remedios
Authors: Granados Salinas Rosario Inés
Published: May 2012

Entre las muchas celebraciones públicas que definieron el espacio urbano de la ciudad de México durante el virreinato, las relacionadas con Nuestra Señora de los Remedios—primera patrona de la capital de la Nueva España—merecen atención especial. Este artículo propone que las 57 veces que la imagen fue traída desde su santuario a la ciudad (en el período de 1577 a 1810), pueden considerarse como autorretratos sociales en los que se mostraba, y definía, la devoción, la lealtad y la política: las procesiones se organizaban en tiempos de sequía, epidemia y guerra, y siempre mostraban los lazos que esta imagen mariana tenía con la conquista y por tanto, con la fundación de la ciudad ya como una entidad colonial.
Investigating a Rural Immersion Experience in Medical Education Utilizing Narrative Inquiry
Authors: Smith C. Cory
Published: May 2012

Lack of access to health care coupled with a severe shortage of physicians is on the forefront of much debate nationally and internationally. Rural areas often suffer the most. Innovations in medical education, such as the creation of rural immersion rotations, are attempting to solve this health crisis. The purpose of this study was to investigate and analyze the narrative writings of 36 fourth–year medical students and primary care residents that participated in a rural immersion rotation in the Mississippi Delta. A grounded theory data analysis led to the emergence of four central themes: Positive reflections of the experience, community health, limited access to health care, and alteration of prior perceptions. The findings of this research provide rich data from the perspective of the medical student and resident. This study concluded that the use of narrative inquiry was beneficial within the rural immersion experience, and the experience positively influenced and impacted medical students and residents.
Healing the Physician’s Story: A Case Study in Narrative Medicine and End–of–Life Care
Authors: Roscoe Lori A.
Published: May 2012

Telling stories after a loved one’s death helps surviving family members to find meaning in the experience and share perceptions about whether the death was consistent with the deceased person’s values and preferences. Opportunities for physicians to evaluate the experience of a patient’s death and to expose the ethical concerns that care for the dying often raises are rare. Narrative medicine is a theoretical perspective that provides tools to extend the benefits of storytelling and narrative sense–making to physicians. This case study describes narrative writing workshops attended by physicians who care for dying patients. The narratives created revealed the physicians’ concerns about ethics and their emotional connection with patients. This case study demonstrates that even one–time reflective writing workshops might create important opportunities for physicians to evaluate their experiences with dying patients and families.
The Mirror of Catullus: Poems 12, 22, 39, 41, 42 and 84
Authors: Shapiro Susan O.
Published: May 2012

In poems 12, 22, 39, 41, 42 and 84, Catullus ridicules his characters for a variety of annoying habits (writing bad poetry, stealing others' belongings, inappropriate smiling, and chronic mispronunciations). The poems have been interpreted as attacks upon their subjects' provincial or low-class origins, but these habits do not result from accidental circumstances. Catullus' characters have purposefully cultivated their habits in order to show off their beauty, wit or talent. Unfortunately, their attempts at self-promotion have the opposite effect; their actions demonstrate that they are far less talented, handsome or witty than they believe themselves to be.
The Violation of the Eye and the Theft of Vision in Lucan's Bellum Civile
Authors: Franzen Christina E.
Published: May 2012

To have one's eye removed represents more than the loss of a body part: without it, humans lose an essential means to communicate and even recognize one another. In this article, I examine the extrusion of eyes in the Bellum Civile , where each instance of eye removal exposes the dysfunction of relationships in Lucan's Rome. The individual citizen, the family and the state display a dearth of introspection, a lack of allegiance to or recognition of friends, family and political allies and an unproductive or perverted desire for intimacy. All these deficits result from mental, intellectual or physical blindness and ultimately contribute to the destruction of the Republic.
The Call of Blood: Greek Origins of a Motif, from Euripides to Heliodorus
Authors: Montiglio Silvia
Published: May 2012

This article attempts to retrace the origins of the motif of "nature's voice" or "the call of blood," which is extensively exploited in early Christian narratives and, in later periods, in drama, especially in France, but an important instance of which appears already in the Greek novel Aethiopica . Previous scholarship has argued that the origin of the motif is in that novel or at any rate in the early Roman period. Instead, this article suggests that traces of the motif can be spotted already in Greek tragedy and philosophy, though the Aethiopica seems to be the first text to theorize it and to give it prominence.
Unearthing Benny the Bulldozer : The Culture of Clearance in Postwar Children’s Books
Authors: Ammon Francesca Russello
Published: May 2012

Alongside the large-scale clearance of buildings and land in the post-World War II United States emerged a body of children’s “bulldozers books” that reflected and endorsed this work. While scholars and adult non-fiction authors have typically treated the bulldozer as symbol of protest, rather than subject of inquiry, postwar children’s book writers and illustrators placed the machine front and center. Through their books, they helped a younger generation make sense of the world around them as their environment underwent massive physical destruction for suburban, highway, and urban renewal construction. They also naturalized real-world clearance processes by promoting this work as technological progress, attempting to involve readers in clearance, and putting a friendly, masculine, all-American face on the machines and their operators. In so doing, the books and their authors advanced a “culture of clearance”—the ideology, technology, policy, and practice of clearing the landscape of its natural and built environment.
Art to Cheat the Common-Weale: Inventors, Projectors, and Patentees in English Satire, ca.1630–70
Authors: Ratcliff Jessica
Published: May 2012

This paper explores early modern ideas about invention and progress by examining the satirical projector character in English literature from the 1630s to the 1670s. It focuses on Simon Sturtevant’s treatise on invention,

Metallica

(1612), and two satires based on it: Thomas Brugis’s pamphlet

Discovery of a Projector

(1641), and John Wilson’s stage comedy

The Projectors

(1665). These satires offered a common critique that was not based on, or even expressed in terms of, scholasticism or the “reverence of antiquity” that Bacon had accused his critics of. Rather, they called out hypocrisy on the rhetoric and politics of what Sturtevant had termed “inventional progression.” Just as royal patronage through patents and monopolies was seen as abusive, projects, too, were depicted not as a force of progress but simply as another means to further enrich the rich and impoverish the poor. Because poets and playwrights were themselves inventors and patentees dependent upon royal favor, their satires were sometimes duplicitous and self-serving.
Investigation of the antibiotic resistance and biofilm formation of Staphylococcus aureus strains isolated from gangrenous mastitis of ewes
Authors: Tel Osman , Aslantaş Özkan , Keskin Oktay , Yilmaz Ebru , Demir Cemil
Published: May 2012

In this study,Staphylococcus aureusstrains (n = 110) isolated from seven ewe flocks in Sanliurfa, Turkey were screened for antibiotic resistance and biofilmforming ability as well as for genes associated with antibiotic resistance and biofilm-forming ability. All isolates were found to be susceptible to oxacillin, gentamicin, clindamycin, cefoxitin, tetracycline, vancomycin, amoxicillin-clavulanic acid, ciprofloxacin and sulphamethoxazole-trimethoprim. The percent proportions of strains resistant to penicillin G, ampicillin and erythromycin were 27.2% (n = 30), 25.4% (n = 28) and 6.3% (n = 7), respectively. Regarding the antibiotic resistance genes, 32 (29%) isolates carried theblaZ and 8 (7.2%) theermC gene. Other resistance genes were not detected in the isolates. All isolates showed biofilm-forming ability on Congo red agar (CRA), while 108 (98.18%) and 101 (91.81%) of them were identified as biofilm producers by the use of standard tube (ST) and microplate (MP) methods, respectively. All isolates carried theicaA andicaD genes but none of them harboured thebapgene. The results demonstrated thatS. aureusisolates from gangrenous mastitis were mainly resistant to penicillins (which are susceptible to the staphylococcal beta-lactamase enzyme), and less frequently to erythromycin. Furthermore, all of theS. aureusisolates produced biofilm which was considered a potential virulence factor in the pathogenesis of staphylococcal mastitis.
Variation in the coding region of the prion protein gene in Slovak cattle
Authors: Hreško Stanislav , Tkáčiková Ľudmila
Published: May 2012

This study was conducted to investigate the presence of single nucleotide polymorphisms (SNPs) in the coding region of the bovine prion protein (PrP) gene among healthy and bovine spongiform encephalopathy (BSE-) affected cattle in Slovakia. Denaturing gradient gel electrophoresis (DGGE) and single-strand conformation polymorphism (SSCP) followed by DNA sequencing were used to identify SNPs and variations in octapeptide repeats. Altogether three single nucleotide polymorphisms (g234a, c339t and c576t) and variations in the number of octapeptide repeat units (5 or 6) were found in the analysed part of the prion protein gene. All single nucleotide polymorphisms were silent, causing no amino acid changes. Significant differences (P < 0.05) in the genotype distribution of g234a polymorphism were observed when the homozygous genotype with a mutated allele (caa/caa) was compared to the heterozygous genotype -/cag among healthy and BSE-affected cattle. The homozygous genotype caa/caa was characteristic of the group of BSE-affected cattle. Additionally, the homozygous genotype caa/caa was significant for the group of Simmental crossbreeds among healthy cattle. The allele and genotype distribution of the other polymorphisms was not significantly different among groups of healthy and BSE-affected cattle. The possible influence of a silent mutation on expression of the gene is not clearly determined and needs further investigations.
Mammary invasive micropapillary carcinoma in a male cat: Immunohistochemical description and clinical follow-up
Authors: Gregório Hugo , Pires Isabel , Seixas Fernanda , Queiroga Felisbina
Published: May 2012

We describe the case of a 14-year-old Domestic Short Hair male cat that presented with a single mammary tumour one centimetre in diameter, classified as invasive micropapillary carcinoma. Histology and immunohistochemistry revealed a high mitotic index, a KI-67 index of 10%, a lack of reactivity to myoepithelial markers, and a dense infiltration with T and B lymphocytes at the periphery of the tumour. Micrometastases were detected in the regional lymph node at the time of surgery. Overall survival time was 10 months with a disease-free interval of 7.5 months. Distant metastases in the sublumbar lymph nodes confirmed the aggressiveness of this tumour, which has recently been subtyped in female cats. This is the first case reported in male cats with a complete follow-up, highlighting the importance of prompt and aggressive treatment in the presence of mammary tumours in male cats.
Efeito de reguladores de crescimento sobre os teores de ácido ascórbico e carboidratos solúveis de morango (Fragaria hybridus)
Authors: Gutierrez Luiz Eduardo , Castro Paulo R. C. , Minami Keigo , Cesar Junior Wilson P.
Published: May 2012

Foram feitas aplicações dos seguintes reguladores de crescimento em morango (Fragarm hybridus): SADH a 5000 ppm, CCC a 2000 ppm, ATA a 10 ppm (3 aplicações), ácido giberélico a 10 ppm (3 aplicações) e 550 ppm. Análises de peso seco, ácido ascórbico e carboidratos solúveis dos frutos foram efetuadas a fim de se estudar o efeito desses reguladores de crescimento. Não foram detectadas diferenças significativas entre os diversas tratamentos e o controle. O peso seco variou de 7,62 a 9,53%. O conteúdo de ácido ascórbico variou de 35,88 a 71,81 mg/100 g de peso fresco. Os teores médios de carboidratos solúveis, expresso em g/100 g peso fresco, foram: totais (5,58), sacarose (1,01), glucose (1,63) e frutose (1,54).
Nutrição mineral de hortaliças. XXI. Absorção de nutrientes por cultivares nacionais de batatinha (Solanum Tuberosum L.)
Authors: Macedo M. C. Motta , Haag H. P. , Gallo J. R.
Published: May 2012

O trabalho teve como objetivo verificar as diferenças na acumulação da matéria seca, absorção e distribuição de nutrientes, entre os cultivares nacionais de batatinha: ARACY, ITAIQUARA, ABAETÊ, TEBERÊ, IAC - 5555 e IAC - 5603. O experimento foi conduzido em condições de campo, de outubro de 1974 a janeiro de 1975, na Estação Experimental de Capão Bonito, do Instituto Agronômico do Estado de São Paulo, em solo do grande grupo Latossol Vermelho Escuro fase orto. Utilizou-se uma adubação N - P2O5 - K6O de 70-300-105 kg/ha no plantio e 70 Kg/ha de nitrogênio em cobertura 45 dias após. As plantas foram amostradas durante o desenvolvimento da cultura em intervalos de 20 dias a partir da germinação até a seca das folhas e hastes. Analisou-se, na matéria seca, os teores de nitrogênio, fósforo, potássio, cálcio, magnésio, enxofre, cobre e ferro. As curvas da marcha de absorção dos nutrientes e produção de matéria seca foram obtidas a partir de dados calculados por equações de regressão ajustadas. Considerou-se como quantidades extraídas. O delineamento estatístico foi o de blocos ao acaso. Detectou-se diferenças significativas na produção de matéria seca, absorção de nutrientes e na exportação de nutrientes. O cultivar IAC - 5603 foi o mais precoce na produção de tuberculos, tendo sido os cultivares mais tardios ABAETÊ e TEBERÊ.