bluuebunny/crossref_metadata_2025 huggingface dataset:
Coalitions in the House?
Authors: Casellas Jason P.
Published: March 2008

What kinds of districts do Latinos and African Americans represent? Are biracial coalitions forming to elect minority candidates in state legislatures? Is it easier for minorities to get elected in lower chamber districts? This article addresses these questions to assess whether Latinos are indeed becoming more alienated from African Americans. Using data from six diverse states and Congress, this article explains the conditions under which African Americans and Latinos are elected to some of the most important legislative institutions in the United States. Among the key findings are that biracial coalitions are not electing minority legislators in all of the states studied. That is, African American majority districts elect African Americans and Latino majority districts elect Latinos. In the U.S. House, however, African American members do benefit from Latino voters.
Abuse Characteristics and Coping Resources as Predictors of Problem-Focused Coping Strategies Among Battered Women
Authors: Sabina Chiara , Tindale R. Scott
Published: March 2008

The current study examines the predictors of three types of problem-focused coping strategies (i.e., amount of help seeking, pursuing an order of protection, and staying away from the abuser) among battered women. Predictor variables are categorized as abuse characteristics and three types of coping resources (i.e., personal, material, and social coping resources). Data from the Chicago Women's Health Risk Study ( N = 478) are used. Results show that enactment of problem-focused coping strategies is associated with amount of abuse, severity, harassment, and power and control tactics. Coping resources such as general health, employment, and social support influence enactment of coping strategies.
No More Black and Blue
Authors: Bronstein Carolyn
Published: March 2008

In the mid-1970s, Women Against Violence Against Women (WAVAW), the first national feminist organization to protest mediated sexual violence against women, pressured the music industry to cease using images of violence against women in its advertising. This article presents a case study of WAVAW's national boycott of Warner Communications, Inc. and documents the activists' successful consumer campaign. The study reveals that media violence was central to feminist organizing efforts, and that WAVAW and related organizations helped establish a climate of concern about violence that motivated scientific research on the relationship between exposure to media violence and subsequent aggression.
Linking Male Use of the Sex Industry to Controlling Behaviors in Violent Relationships
Authors: Simmons Catherine A. , Lehmann Peter , Collier-Tenison Shannon
Published: March 2008

In an attempt to better understand the relationship between male use of the sex industry (i.e., pornography and strip clubs) and interpersonal violence (IPV), 2,135 female residents of an IPV shelter were surveyed regarding their batterer's use of both the sex industry and controlling behaviors in their relationship. Findings indicate that male domestic violence offenders who utilize the sex industry use more controlling behaviors than male domestic violence offenders who do not. Implications for policy, practice, and research are discussed.
Targeted Sampling in Drug Abuse Research: A Review and Case Study
Authors: Peterson James A. , Reisinger Heather Schacht , Schwartz Robert P. , Mitchell Shannon Gwin , Kelly Sharon M. , Brown Barry S. , Agar Michael H.
Published: March 2008

Locating and recruiting out-of-treatment drug-dependent individuals for inclusion in research studies are important and challenging tasks. Targeted sampling, a technique to reach such populations, has been described in the substance abuse literature. However, this literature has generally lacked a recent detailed account of the procedures for planning and implementing targeted sampling. This article provides a review of the literature of targeted sampling in drug abuse studies and a detailed description of methodology employed in our ongoing study of entry and engagement among opioid-dependent individuals in Baltimore, Maryland. Findings indicate that the out-of-treatment samples recruited from the streets are quite similar to those recruited from new admissions to opioid treatment programs, except for their prior treatment experience. This article indicates that targeted sampling can be useful in an urban setting with pervasive drug use.
Nutrition for Women in the Prevention and Treatment of Type 2 Diabetes and Cardiovascular Diseases
Authors: Melanson Kathleen J.
Published: March 2008

Awareness of women's risks for type 2 diabetes and cardiovascular diseases must be promoted by health care professionals. For overweight and obese women, weight reduction is critical for reducing risks; prevention of excess weight gain must be encouraged for women of healthy body weight. Vulnerable times for weight gain during a woman's life cycle include early adulthood, the childbearing years, and menopause. Thus, healthy diet and exercise behaviors must be particularly emphasized during these years. Polycystic ovary syndrome is also associated with obesity, insulin resistance, and cardiovascular disease risk, and weight loss can lower these risks. Foods comprising diets associated with reduced cardiovascular disease and type 2 diabetes risks tend to be unrefined plant foods (vegetables, legumes, fruits, whole grains, nuts, seeds), low-fat dairy products, fish rich in omega-3 fatty acids, and lean sources of protein. Artificial trans fatty acids should be avoided and saturated fats cholesterol, sodium, and added sugars minimized. A balance of micro-nutrients and fiber should be obtained from wholesome food sources rather than supplements. Dietary counseling for women should consider the context in which they live, cultural aspects, socioeconomic factors, menstrual cycle influences on food intake, and warning signs for eating disorders. Continued gender-specific research will be helpful in discerning the most effective lifestyle interventions for women.
Is the routine pressure dressing after thyroidectomy necessary? A prospective randomized controlled study
Authors: Piromchai Patorn , Vatanasapt Patravoot , Reechaipichitkul Wisoot , Phuttharak Warinthorn , Thanaviratananich Sanguansak
Published: March 2008

Background

An acute complication of thyroidectomy is fatal hematoma, which can produce an upper airway obstruction needing immediate intubation or tracheostomy. After neck surgery, we usually apply a pressure dressing with a non-woven, adhesive fabric to reduce bleeding and fluid collection at the operative bed. We conducted a prospective, randomized, controlled study to evaluate a pressure vs. a non-pressure dressing after thyroid surgery by monitoring blood and serum in the operative bed.

Methods

We studied 108 patients who underwent 116 thyroid surgeries at Srinagarind Hospital, Khon Kaen University, between December 2006 and September 2007. The patients were randomized to either the pressure dressing or non-pressure dressing group. Ultrasound of the neck was performed 24 ± 3 hours after surgery. The volume of fluid collection in the operative bed was calculated. All patients were observed for any post-operative respiratory distress, wound complications, tingling sensation or tetany.

Results

The distributions of age, sex, surgical indications and approaches were similar between the two groups. There was no statistically significant difference in the volume of fluid collection in the operative bed (p = 0.150) and the collected drained content (p = 0.798). The average time a drain was retained was 3 days. One patient in the pressure dressing group suffered cutaneous bruising while one patient in the non-pressure dressing group developed immediate hemorrhage after the skin sutures.

Conclusion

Pressure dressing after thyroidectomy does not have any significant impact on decreasing fluid collection at the operative bed. The use of pressure dressing after thyroidectomy may not therefore be justified.

Trial Registration

NCT00400465, ISRCTN52660978
Clinical utility of tissue Doppler imaging in patients with acute myocardial infarction complicated by cardiogenic shock
Authors: Hameed Adnan K , Gosal Tirath , Fang Tielan , Ahmadie Roien , Lytwyn Matthew , Barac Ivan , Zieroth Shelley , Hussain Farrukh , Jassal Davinder S
Published: March 2008

Background

Echocardiography is widely used in the management of patients with cardiogenic shock (CS). Left ventricular ejection fraction (EF) has been shown to be an independent predictor of survival in CS. Tissue Doppler Imaging (TDI) is a sensitive echocardiographic technique that allows for the early quantitative assessment of regional left ventricular dysfunction. TDI derived indices, including systolic velocity (S'), early (E') and late (A') diastolic velocities of the lateral mitral annulus, are reduced in heart failure patients (EF < 30%) and portend a poor prognosis. In CS patients, the application of TDI prior to revascularization remains unknown.

Objective

To characterize TDI derived indices in CS patients as compared to patients with chronic CHF.

Methods

Between 2006 and 2007, 100 patients were retrospectively evaluated who underwent echocardiography for assessment of LV systolic function. This population included: Group I) 50 patients (30 males, 57 ± 13 years) with chronic CHF as controls; and Group II) 50 patients (29 males, 58 ± 10 years) with CS. Spectral Doppler indices including peak early (E) and late (A) transmitral velocities, E/A ratio, and E-wave deceleration time were determined. Tissue Doppler indices including S', E' and A' velocities of the lateral annulus were measured.

Results

Of the entire cohort, the mean LVEF was 25 ± 5%. Cardiogenic shock patients demonstrated significantly lower lateral S', E' and a higher E/E' ratio (p < 0.01), as compared to CHF patients. The in-hospital mortality in the CHF cohort was 5% as compared to the CS group with an in hospital mortality of 40%. In the subset of CS patients (n = 30) who survived, the mean S' at presentation was higher as compared to those patients who died in hospital (3.5 ± 0.5 vs. 1.8 ± 0.5 cm/s).

Conclusion

Despite similar reduction in LV systolic function, CS patients have reduced myocardial velocities and higher filling pressures using TDI, as compared to CHF patients. Whether TDI could be a reliable tool to determine CS patients with the best chance of recovery following revascularization is yet to be determined.
Biomarkers of inflammation, coagulation and fibrinolysis predict mortality in acute lung injury
Authors: McClintock Dana , Zhuo Hanjing , Wickersham Nancy , Matthay Michael A , Ware Lorraine B
Published: March 2008

Background

Acute lung injury (ALI) is a major cause of acute respiratory failure with high mortality despite lung-protective ventilation. Prior work has shown disordered inflammation and coagulation in ALI, with strong correlations between biomarker abnormalities and worse clinical outcomes. We measured plasma markers of inflammation, coagulation and fibrinolysis simultaneously to assess whether these markers remain predictive in the era of lung-protective ventilation.

Methods

Plasma samples and ventilator data were prospectively collected from 50 patients with early ALI. Plasma biomarkers of inflammation (IL-6, IL-8, intercellular adhesion molecule 1), of coagulation (thrombomodulin, protein C) and of fibrinolysis (plasminogen activator inhibitor 1) were measured by ELISA. Biomarker levels were compared between survivors (n = 29) and non-survivors (n = 21) using Mann–Whitney analysis.

Results

The tidal volume for the study group was 6.6 ± 1.1 ml/kg predicted body weight and the plateau pressure was 25 ± 7 cmH2O (mean ± standard deviation), consistent with lung-protective ventilation. All markers except IL-6 were significantly different between survivors and nonsurvivors. Nonsurvivors had more abnormal values. Three biomarkers – IL-8, intercellular adhesion molecule 1 and protein C – remained significantly different by multivariate analysis that included age, gender, Simplified Acute Physiology Score II and all biomarkers that were significant on bivariate analysis. Higher levels of IL-8 and intercellular adhesion molecule 1 were independently predictive of worse outcomes (odds ratio = 2.0 and 5.8, respectively; P = 0.04 for both). Lower levels of protein C were independently associated with an increased risk of death (odds ratio = 0.5), a result that nearly reached statistical significance (P = 0.06).

Conclusion

Despite lung-protective ventilation, abnormalities in plasma levels of markers of inflammation, coagulation and fibrinolysis predict mortality in ALI patients, indicating more severe activation of these biologic pathways in nonsurvivors.
Resistance of Janus Kinase-2 Dependent Leptin Signaling in Natural Killer (NK) Cells: A Novel Mechanism of NK Cell Dysfunction in Diet-Induced Obesity
Authors: Nave Heike , Mueller Guenter , Siegmund Britta , Jacobs Roland , Stroh Thorsten , Schueler Ulrike , Hopfe Matthias , Behrendt Patrick , Buchenauer Tobias , Pabst Reinhard , Brabant Georg
Published: March 2008

Leptin acts not only as an anorexigenic hormone but also regulates cell-mediated immunity via leptin receptors (Ob-R) expressed on T and B lymphocytes. However, the impact of leptin on natural killer (NK) cells is currently elusive. We evaluated leptin effects on NK cells in relation to the body weight in rats using in vivo and in vitro approaches. Leptin was injected iv in male lean and diet-induced obese Lewis and F344 rats. NK cell numbers were analyzed in blood and spleen by fluorescence activated cell sorting and immunohistochemistry, and the activity of NK cells was measured by chromium release assay. Ob-R expression was investigated by confocal laser scanning and quantitative RT-PCR. To compare leptin-dependent intracellular signaling under basal and leptin- and tumor cell (MADB106)-stimulated conditions, intracellular target proteins of NK cells were evaluated by Western blotting. Number and distribution pattern of splenic NK cells were significantly different in lean and obese animals. Leptin administration resulted in a 4-fold higher stimulation of the NK activity in lean than obese animals. This was not due to a decreased expression of Ob-R because quantitative RT-PCR revealed significantly higher Ob-Rb mRNA levels in NK cells from obese rats. In contrast, postreceptor signaling is differentially abrogated in obese animals with significantly lower activation of postreceptor signaling components (Janus kinase-2p, protein kinase B pT308, AMPαpT172) after an in vivo leptin challenge. In conclusion, the results for the first time assign leptin a central role as a modulator of NK cell number and activity only in lean but not obese subjects. The differential role of leptin has important implications for the influence of body weight in the response to systemic inflammations and in the immunological defense of cancer.
A Conditional Knockout Mouse Line of the Oxytocin Receptor
Authors: Lee Heon-Jin , Caldwell Heather K. , Macbeth Abbe H. , Tolu Selen G. , Young W. Scott
Published: March 2008

Oxytocin plays important roles in reproductive physiology and various behaviors, including maternal behavior and social memory. Its receptor (Oxtr) is present in peripheral tissues and brain, so a conditional knockout (KO, −/−) would be useful to allow elimination of the receptor in specific sites at defined times. We created a line of mice in which loxP sites flank Oxtr coding sequence (floxed) enable Cre recombinase-mediated inactivation of the receptor. We expressed Cre recombinase in these mice either in all tissues (Oxtr−/−) or the forebrain (OxtrFB/FB) using the Ca2+/calmodulin-dependent protein kinase IIα promoter. The latter KO has reduced Oxtr binding beginning 21–28 d postnatally, leading to prominent reductions in the lateral septum, hippocampus, and ventral pallidum. The medial amygdala is spared, and there is significant retention of binding within the olfactory bulb and nucleus and neocortex. We did not observe any deficits in the general health, sensorimotor functions, anxiety-like behaviors, or sucrose intake in either Oxtr−/− or OxtrFB/FB mice. Females of both KO types deliver pups, but only the OxtrFB/FB mice are able to eject milk. Oxtr−/− males show impaired social memory for familiar females, whereas the OxtrFB/FB males appear to recognize their species but not individuals. Our results confirm the importance of oxytocin in social recognition and demonstrate that spatial and temporal inactivation of the Oxtr will enable finer understanding of the physiological, behavioral, and developmental roles of the receptor.
RNA interference screening inDrosophilaprimary cells for genes involved in muscle assembly and maintenance
Authors: Bai Jianwu , Binari Richard , Ni Jian-Quan , Vijayakanthan Marina , Li Hong-Sheng , Perrimon Norbert
Published: March 2008

To facilitate the genetic analysis of muscle assembly and maintenance, we have developed a method for efficient RNA interference (RNAi) in Drosophila primary cells using double-stranded RNAs (dsRNAs). First,using molecular markers, we confirm and extend the observation that myogenesis in primary cultures derived from Drosophila embryonic cells follows the same developmental course as that seen in vivo. Second, we apply this approach to analyze 28 Drosophila homologs of human muscle disease genes and find that 19 of them, when disrupted, lead to abnormal muscle phenotypes in primary culture. Third, from an RNAi screen of 1140 genes chosen at random, we identify 49 involved in late muscle differentiation. We validate our approach with the in vivo analyses of three genes. We find that Fermitin 1 and Fermitin 2, which are involved in integrin-containing adhesion structures, act in a partially redundant manner to maintain muscle integrity. In addition, we characterize CG2165,which encodes a plasma membrane Ca2+-ATPase, and show that it plays an important role in maintaining muscle integrity. Finally, we discuss how Drosophila primary cells can be manipulated to develop cell-based assays to model human diseases for RNAi and small-molecule screens.
Computer simulation of emerging asymmetry in the mouse blastocyst
Authors: Honda Hisao , Motosugi Nami , Nagai Tatsuzo , Tanemura Masaharu , Hiiragi Takashi
Published: March 2008

The mechanism of embryonic polarity establishment in mammals has long been controversial. Whereas some claim prepatterning in the egg, we recently presented evidence that mouse embryonic polarity is not established until blastocyst and proposed the mechanical constraint model. Here we apply computer simulation to clarify the minimal cellular properties required for this morphology. The simulation is based on three assumptions: (1) behavior of cell aggregates is simulated by a 3D vertex dynamics model; (2) all cells have equivalent mechanical properties; (3) an inner cavity with equivalent surface properties is gradually enlarged. However, an initial attempt reveals a requirement for an additional assumption: (4) the surface of the cavity is firmer than intercellular surfaces, suggesting the presence of a basement membrane lining the blastocyst cavity, which is indeed confirmed by published data. The simulation thus successfully produces a structure recapitulating the mouse blastocyst. The axis of the blastocyst, however, remains variable,leading us to an additional assumption: (5) the aggregate is enclosed by a capsule, equivalent to the zona pellucida in vivo. Whereas a spherical capsule does not stabilize the blastocyst axis, an ellipsoidal capsule eventually orients the axis in accordance with its longest diameter. These predictions are experimentally verified by time-lapse recordings of mouse embryos. During simulation, equivalent cells form two distinct populations composed of smaller inner cells and larger outer cells. These results reveal a unique feature of early mammalian development: an asymmetry may emerge autonomously in an equivalent population with no need for a priori intrinsic differences.
Neural stem cells: balancing self-renewal with differentiation
Authors: Doe Chris Q.
Published: March 2008

Stem cells are captivating because they have the potential to make multiple cell types yet maintain their undifferentiated state. Recent studies of Drosophila and mammalian neural stem cells have shed light on how stem cells regulate self-renewal versus differentiation and have revealed the proteins, processes and pathways that all converge to regulate neural progenitor self-renewal. If we can better understand how stem cells balance self-renewal versus differentiation, we will significantly advance our knowledge of embryogenesis, cancer biology and brain evolution, as well as the use of stem cells for therapeutic purposes.
Neuropilin 1 and 2 control cranial gangliogenesis and axon guidance through neural crest cells
Authors: Schwarz Quenten , Vieira Joaquim M. , Howard Beatrice , Eickholt Britta J. , Ruhrberg Christiana
Published: March 2008

Neuropilin (NRP) receptors and their class 3 semaphorin (SEMA3) ligands play well-established roles in axon guidance, with loss of NRP1, NRP2, SEMA3A or SEMA3F causing defasciculation and errors in growth cone guidance of peripherally projecting nerves. Here we report that loss of NRP1 or NRP2 also impairs sensory neuron positioning in the mouse head, and that this defect is a consequence of inappropriate cranial neural crest cell migration. Specifically, neural crest cells move into the normally crest-free territory between the trigeminal and hyoid neural crest streams and recruit sensory neurons from the otic placode; these ectopic neurons then extend axons between the trigeminal and facioacoustic ganglia. Moreover, we found that NRP1 and NRP2 cooperate to guide cranial neural crest cells and position sensory neurons; thus, in the absence of SEMA3/NRP signalling, the segmentation of the cranial nervous system is lost. We conclude that neuropilins play multiple roles in the sensory nervous system by directing cranial neural crest cells,positioning sensory neurons and organising their axonal projections.
Tbx3 controls the fate of hepatic progenitor cells in liver development by suppressingp19ARFexpression
Authors: Suzuki Atsushi , Sekiya Sayaka , Büscher Dirk , Izpisúa Belmonte Juan Carlos , Taniguchi Hideki
Published: March 2008

Although the T-box family of transcription factors function in many different tissues, their role in liver development is unknown. Here we show that Tbx3, the T-box gene that is mutated in human ulnar-mammary syndrome, is specifically expressed in multipotent hepatic progenitor cells,`hepatoblasts', isolated from the developing mouse liver. Tbx3-deficient hepatoblasts presented severe defects in proliferation as well as uncontrollable hepatobiliary lineage segregation, including the promotion of cholangiocyte (biliary epithelial cell) differentiation, which thereby caused abnormal liver development. Deletion of Tbx3 resulted in the increased expression of the tumor suppressor p19ARF(Cdkn2a), which in turn induced a growth arrest in hepatoblasts and activated a program of cholangiocyte differentiation. Thus, Tbx3 plays a crucial role in controlling hepatoblast proliferation and cell-fate determination by suppressing p19ARF expression and thereby promoting liver organogenesis.
A sugar rush for developmental biology
Authors: Merry Catherine L. R. , Ward Christopher M.
Published: March 2008

The EMBO Workshop on Glycoscience and Development, organised by Philippe Delannoy, Yann Guérardel, Tony Merry and Jean-Claude Michalski, was held in the picturesque, contemplative environment of Les Minimes, a converted seventeenth century Flemish convent in Lille, France, in December 2007. A cross-section of researchers, both confirmed `glycomaniacs' and those newer to the field, discussed and debated recent advances in the field of glycobiology. Presentations ranged from the clinical applications of glycobiology to novel approaches for unravelling carbohydrate biosynthesis in developmental settings and models, such as the fruit fly, nematode and zebrafish.
Round‐robin test for X‐ray stress analysis standards: Optimization for discrepancy reduction
Authors: Ferreira C , François M , Guillén R
Published: March 2008

The aim of this paper is to shed some light on the discrepancy origins of a round‐robin test for X‐ray stress analysis in order to improve the specimen quality and to establish new guidelines for the coming works on set‐up certification. After a global overview of the return measurements and certificates, an original analysis method is proposed with a detailed study of the raw results emphasizing the most relevant uncertainties. It is shown that the standardization of stress calculus parameters widely reduces the inter‐laboratory discrepancy. A comparative analysis of the experimental patterns with some of the most common peak localization techniques also shows the importance of providing this information together with the stress values calculated even with quasi‐ideal cases such as shot‐peened aluminium alloy specimens. In this way, the value distributions can be easily fitted with a simple statistical law which allows the mean stress value to be considered as more representative.
Design of notches and grooves by means of elliptic shapes
Authors: Pedersen N L , Pedersen P
Published: March 2008

For machine elements that must also be designed with respect to fatigue, the stress concentration factor for notches and grooves is an important quantity. Traditional designs with circular shapes are not advantageous and, in the present paper, it is shown that stress concentration factors can be reduced significantly without the need for complicated shapes. To keep the shape simple, the circular shapes are modified into elliptic shapes with only one design parameter: the ratio of the ellipse half‐axes.

Comparisons with classical results are performed for notches in two‐dimensional flat tensile bars and for grooves in axisymmetric tensile shafts. In general, the detailed finite element analyses agree well with these results and this gives confidence in the improved designs. Shapes are obtained with constant maximum stress along a major part of the elliptic shape, and the stress concentration factors are reduced considerably.
Low-cost carbon-fibre-based automotive body panel systems: A performance and manufacturing cost comparison
Authors: Turner T A , Harper L T , Warrior N A , Rudd C D
Published: March 2008

Carbon—;fibre—;based composite manufacturing processes have been considered for automotive body panel applications. A full—;scale front wing—fender component was produced using two composite manufacturing processes (a semi—;impregnated (semi—;preg) system and a novel directed fibre preforming—resin transfer moulding process) and compared with an existing stamped steel component for mechanical properties, weight saving, and cost, using a technical—;cost—;modelling procedure. Mechanical testing demonstrates that the carbon fibre composite solutions can provide 40—50 per cent weight saving for an equivalent bending stiffness to steel panels and greatly improved dent resistance. For the part studied, carbon fibre semi—;preg systems offered the lowest cost process up to around 500 parts/annum and directed fibre preforming technologies were cheaper between 500 and 9000 parts/annum. The steel component was seen to be more cost effective at volumes above around 9000 parts/annum.
Improvement in numerical reconstruction for vehicle—pedestrian accidents
Authors: Shen J , Jin X-L
Published: March 2008

A full-scale vehicle—pedestrian crash simulation has been applied to pedestrian accident reconstruction worldwide in the past decade. Considering that the optimization method and pedestrian human model play an important role in this simulation, this study makes some improvements in them according to the characteristics of real-world pedestrian accidents. On the one hand, the sequential linear programming method replaces classical manual optimization for pedestrian accident reconstruction which can automatically vary pre-impact parameters to minimize the error between simulation and real data. On the other hand, new anthropometry results and coupled finite element (FE)—multi-body (MB) modelling technology are applied to pedestrian human modelling. A Chinese pedestrian model generator is developed in order to avoid using the Western human population in China, and an FE leg model is combined into the MB pedestrian model to perform a more detailed analysis of long bone fracture.

The purpose of this paper is to evaluate the capability of and necessity for the above improvements. The evaluation is conducted by the reconstruction of three fatal pedestrian accidents. The first two cases are mathematically reconstructed on the basis of the rest position and pedestrian injury respectively. The influence of the anthropometry parameters is illustrated by the reconstruction of the last case.
Investigation of early soot formation process in a diesel spray flame via excitation—emission matrix using a multi-wavelength laser source
Authors: Aizawa T , Kosaka H
Published: March 2008

In order to investigate the early soot formation processes in diesel combustion, spectral analysis of polycyclic aromatic hydrocarbons (PAHs) formed in the early soot formation region in a diesel spray flame was conducted via the excitation—emission matrix (EEM) technique using a multi-wavelength laser source. The experiments were conducted using an optically accessible constant volume combustion vessel under diesel-like conditions (ambient temperature, Ta = 750–1130 K and ambient pressure, Pa = 2.0–3.0 MPa) at different ambient oxygen concentrations (10–21 per cent). The PAHs formed in a diesel spray flame in the combustion vessel were excited by a coherent multi-wavelength ‘rainbow’ laser light (mainly 266, 299, 342, and 398 nm, total 20 mJ) generated by converting the fourth harmonic (266 nm, 60 mJ) of a pulsed neodymium-doped yttrium aluminium garnet (Nd:YAG) laser using a Raman cell frequency converter filled with hydrogen (500 kPa). The spectra of laser-induced fluorescence from the PAHs excited by the different laser wavelengths in the flame were simultaneously captured with a spectrometer and an intensified charge-coupled device (ICCD) camera as EEM images. The EEM measured in diesel spray flames at different ambient temperatures and oxygen concentrations revealed that the timing and the region for PAH growth and soot particle formation are delayed and extended downstream at lower ambient temperatures and oxygen concentrations. At an ambient temperature of 940 K and an ambient oxygen concentration of 21 per cent, a variety of PAHs are detected around the ignition timing in the central region of the diesel spray flame and the PAHs grow into larger PAHs and soot particles as the combustion process progresses. At a lower ambient temperature of 750 K or lower ambient oxygen concentrations down to 10 per cent, the fluorescence from PAHs is detected in the central region of the diesel spray flame before the ignition timing and the intensity and the spectral characteristics of the PAH fluorescence do not change for a longer period until they are finally converted to soot particles in the downstream regions in the spray flame.
Synthesis and Stereochemical Assignment of Angucycline Antibiotic, PD-116740
Authors: Mori Keiji , Tanaka Yuuya , Ohmori Ken , Suzuki Keisuke
Published: March 2008

The first total synthesis and absolute structure assignment of PD-116740 (2) was achieved by exploiting two key steps: 1) a thermal ring expansion of a benzocyclobutene derivative, and 2) pinacol cyclization of biaryl dialdehyde.
Research Note—A Value-at-Risk Approach to Information Security Investment
Authors: Wang Jingguo , Chaudhury Aby , Rao H. Raghav
Published: March 2008

Information security investment has been getting increasing attention in recent years. Various methods have been proposed to determine the effective level of security investment. However, traditional expected value methods (such as annual loss expectancy) cannot fully characterize the information security risk confronted by organizations, considering some extremal yet perhaps relatively rare cases in which a security failure may be critical and cause high losses. In this research note we introduce the concept of value-at-risk to measure the risk of daily losses an organization faces due to security exploits and use extreme value analysis to quantitatively estimate the value at risk. We collect a set of internal daily activity data from a large financial institution in the northeast United States and then simulate its daily losses with information based on data snapshots and interviews with security managers at the institution. We illustrate our methods using these simulated daily losses. With this approach, decision makers can make a proper investment choice based on their own risk preference instead of pursuing a solution that minimizes only the expected cost.
Firm R&D Behavior and Evolving Technology in Established Industries
Authors: Knott Anne Marie , Posen Hart E.
Published: March 2008

One of the key mechanisms of firms' strategic renewal is R&D, and a key driver of the intensity of R&D is industry context. A number of theories develop propositions linking industry factors to firm R&D behavior, but these theories lack consensus. To date, empirical tests have been unable to resolve the competing predictions because of lack of time-varying measures of technology. We create new measures for technology and then conduct a test of the competing theories. Our results indicate that the data best match a model of innovative behavior in which firms invest in R&D principally to regain eroded advantage rather than to pursue the new frontier.
Stereoselectivity of the Petasis reaction with various chiral amines and styrenylboronic acids
Authors: Churches Quentin I. , Stewart Helen E. , Cohen Scott B. , Shröder Adam , Turner Peter , Hutton Craig A.
Published: March 2008

Several chiral amines were investigated for the stereoselective preparation of homophenylalanine derivatives using the Petasis reaction. Chiral secondary amines such as N,α-dimethylbenzylamine and N-benzylphenylglycinol gave the best results in terms of both yield and diastereoselectivity. The use of N-benzylphenylglycinol leads directly to 3-alkenyl-4-benzyl-5-phenyloxazin-2-one products. Intriguing variation was observed in the stereoselectivity of reactions employing para-substituted styrenylboronic acid substrates, where presumably only electronic factors are involved.
Schoenberg's Interior Designs
Authors: Watkins Holly
Published: March 2008

Familiar accounts of fin-de-siècle Vienna tend to view Arnold Schoenberg's atonal works and Adolf Loos's anti-ornamental polemics as expressions of similar modernist principles. But although the two friends were equally determined to challenge bourgeois standards of beauty, the calm appearance of Loos's buildings, whose denuded facades shielded plush yet refined interiors, is hard to reconcile with Schoenberg's radically dissonant and expressive music circa 1910. This divergence can be understood in terms of contrasting responses to urban modernity. While Loos's architecture facilitated a retreat inward, Schoenberg's release of unconscious impulses into the compositional process mimicked the psychological breakdown Georg Simmel believed to threaten city dwellers—a breakdown in which inner and outer realms were no longer distinguishable. Situating Schoenberg's music in relation to the problem of interiority in modern metropolitan life, I argue that the composer's creative aesthetics began to converge with those of Loos only later in his career. By incorporating concealment into the very fabric of twelve-tone music, Schoenberg took an “inward turn” resembling Loos's architectural efforts to protect subjectivity from needless exposure. The increasing emphasis on multidimensionality in Schoenberg's discussions of twelve-tone musical space also betrays the influence of Loos's innovations in interior space planning in the 1920s and 1930s. Harnessing the psychological and sociological aims of Loos's designs as tools of interpretation, I propose that the twelve-tone method represents a renewed commitment to privacy and interiority in the face of the externalizing impulses of urban modernity.
Louis Armstrong, Eccentric Dance, and the Evolution of Jazz on the Eve of Swing
Authors: Harker Brian
Published: March 2008

From the summer of 1926 to the summer of 1927, Louis Armstrong entered into a partnership at the Sunset Café in Chicago with a husband-and-wife dance team called Brown and McGraw. In doing so, he took part in a long-forgotten tradition of early jazz trumpet players accompanying dancers. The practice began in 1924 with pantomime artist Johnny Hudgins and his many trumpet-playing assistants. Like these trumpeters, Armstrong appeared on-stage with the dancers, playing rehearsed—though not written—solos that closely matched their steps, movements, or facial expressions. Dancers Brown and McGraw had Armstrong's lines notated in an arrangement, allowing them to hire other trumpet players to accompany them whenever they went out on tour. They were known for a dancing style that was fast, acrobatic, and unpredictable—attributes that also describe Armstrong's playing from this period. The rhythmic sensibility the three of them shared seems to have produced fertile interactions. During the time of their collaboration, Armstrong made a major shift in his approach to rhythm. Whereas previously he had tended to rely on more or less fixed rhythmic modules, some of which he inherited from ragtime, his recordings in late 1926 and 1927 reveal a rhythmic vocabulary that is free, flexible, and endlessly inventive—the foundation for the new jazz language that would emerge in the Swing Era.
Avaliação ecocardiográfica em bezerros da raça Holandesa
Authors: Michima Lilian E.S. , Leal Marta L.R. , Bertagnon Heloísa G. , Fernandes Wilson R. , Benesi Fernando J.
Published: March 2008

Com o objetivo de estabelecer valores de medidas ecocardiográficas em bezerros da raça Holandesa, utilizaram-se 25 animais, com idade entre 8 e 28 dias e peso entre 27 e 57 kg. Procedeu-se o exame ecocardiográfico em modo-B e modo-M para a obtenção dos valores médios dos seguintes parâmetros, em diástole e sístole, respectivamente: diâmetros internos dos ventrículos direito (2,05±0,13cm e 1,59±0,13cm) e esquerdo (3,91±0,09cm e 2,52±0,13cm), espessuras do septo interventricular (1,24±0,04cm e 1,62±0,06cm) e da parede livre do ventrículo esquerdo (0,92±0,04cm e 1,50±0,05cm). Obtiveram-se ainda valores do diâmetro dos átrios direito e esquerdo em sístole (2,97±0,12cm e 4,11±0,21cm, respectivamente), dos volumes diastólico (67,90±3,65ml), sistólico (25,32±3,05ml) e de ejeção (42,58±2,46ml) do ventrículo esquerdo, do débito cardíaco (3857±339ml/min), do diâmetro aórtico (2,52±0,05cm), da distância entre o ponto de maior abertura do folheto anterior da valva atrioventricular esquerda até o septo interventricular (0,65±0,08cm) e tempo de ejeção (0,39±0,02s), das frações de encurtamento (36,27±2,40%) e de ejeção do ventrículo esquerdo (64,67±3,22%). Houve média correlação linear positiva (66,4%, P<0,01) entre diâmetro aórtico e peso dos animais, média correlação linear negativa (P<0,01) entre tempo de ejeção do ventrículo esquerdo e freqüência cardíaca (69,1%) e com o débito cardíaco (62,4%). Observou-se uma tendência dos bezerros em apresentar menor diâmetro da câmara cardíaca esquerda, apesar de mantidas as relações de espessura de parede e índices funcionais do miocárdio.
A dinâmica da taxa de lucro, da taxa de juros e do grau de utilização da capacidade produtiva em um modelo pós-keynesiano
Authors: Carvalho Luciano Dias de , Oreiro José Luís
Published: March 2008

O objetivo do presente artigo é analisar, por meio de simulação computacional, as trajetórias dinâmicas da taxa de acumulação de capital, da taxa de lucro, da taxa de juros e do grau de utilização da capacidade diante de mudanças exógenas do ritmo do progresso tecnológico e da propensão a poupar dos capitalistas. A simulação foi realizada a partir de um modelo macrodinâmico pós-keynesiano que leva em consideração a interação entre o lado real e monetário da economia. Dentre outros resultados, as simulações mostraram que: (i) a taxa de lucro é significativamente elástica com relação a um choque tecnológico positivo, ao passo que a taxa de juros e o grau de utilização da capacidade são pouco sensíveis a esse tipo de choque; e (ii) a confirmação do paradoxo da frugalidade, segundo o qual o aumento da propensão a poupar dos capitalistas acaba por reduzir o nível da poupança agregada, a taxa de lucro e o grau de utilização da capacidade.
Álcool combustível e biodiesel no Brasil: quo vadis?
Authors: Paulillo Luiz Fernando , Vian Carlos Eduardo de Freitas , Shikida Pery Francisco Assis , Mello Fabiana Tanoue de
Published: March 2008

O objetivo deste estudo é fazer uma análise das cadeias agroenergéticas do álcool combustível e do biodiesel no Brasil, à guisa do referencial neocorporativista. Como resultado, um dos desafios da cadeia brasileira do álcool é apurar as dimensões do mercado externo e interno de álcool que se vislumbram, para viabilizar um planejamento estratégico de expansão da oferta de cana e de álcool. Já a cadeia do biodiesel depende, assim como o Proálcool em seus primórdios, de um paradigma subvencionista em sua fase inicial. Seu futuro está atrelado ao comportamento do preço do petróleo e da direção que irá tomar a orquestração de interesses em torno do biodiesel.
Custos e escala de produção na pecuária leiteira: estudo nos principais estados produtores do Brasil
Authors: Lopes Patrick Fernandes , Reis Ricardo Pereira , Yamaguchi Luiz Carlos Takao
Published: March 2008

Por meio deste trabalho objetivou-se comparar duas metodologias de apuração de custos e identificar escalas na pecuária leiteira dos principais estados produtores de leite no Brasil. Estimaram-se as funções de custos de produção da atividade leiteira, considerando-se essas duas metodologias, definidas por "custo da atividade leiteira" e "centro de custos leite". Analisaram-se dados técnicos e econômicos de 162 propriedades rurais, abrangendo o período de agosto de 2000 a julho de 2001. A apuração de custos pela metodologia de "centro de custos" possibilitou uma maior precisão em relação às análises do custo total médio, evidenciando que, quando apurados os custos relacionados ao subsistema leite, os preços recebidos foram suficientes para remunerar o produtor. Ficou evidente a ocorrência de economias de escala. A análise dos indicadores evidencia que o estudo é composto por produtores que buscam maior eficiência produtiva e que ainda possuem possibilidades de ganho no que se refere à alocação e aproveitamento dos recursos. Entretanto, a possibilidade de redução dos custos médios é mais significativa para o sistema global de produção que para o subsistema leite, indicando que os demais subsistemas da atividade global apresentam um desempenho inferior quanto ao aproveitamento dos recursos produtivos e gerenciais em relação ao subsistema de produção de leite.
Análise de transmissão de preços do mercado atacadista de melão do Brasil
Authors: Mayorga Rodrigo de Oliveira , Khan Ahmad Saeed , Mayorga Ruben Dario , Lima Patrícia Verônica Pinheiro Sales , Margarido Mario Antônio
Published: March 2008

O presente estudo se propôs a analisar a relação existente entre os mercados atacadistas de melão amarelo no Brasil. Para analisar a transmissão de preços entre estes mercados, utilizaram-se métodos de séries de tempo, teste de raiz unitária, teste de co-integração de Johansen, o modelo Auto-regressivo Vetorial (VAR), decomposição da variância dos erros de previsão e função resposta ao impulso. O período analisado abrangeu janeiro de 2001 a dezembro de 2005. Os resultados mostraram que, apesar dos pólos Açu/Mossoró-RN e Baixo Jaguaribe-CE representarem as maiores áreas produtoras nacionais de melão, variações nos preços de atacado de melão amarelo das Centrais de Abastecimento de Natal e Fortaleza, não afetam de maneira significativa os preços dos outros mercados estudados. No entanto, variações nos preços da Companhia de Entrepostos e Armazéns Gerais de São Paulo (CEAGESP) têm impacto sobre todos os mercados atacadistas analisados. Assim sendo, a CEAGESP, representando os atacadistas nacionais, e sendo a maior intermediadora do país, comanda o mercado brasileiro de melão amarelo comercializado, constituindo, na prática, um mercado oligopolístico.
Aplicação de retalho cutâneo no tratamento cirúrgico do hemangiopericitoma canino
Authors: Matera Julia Maria , Sakuma Cinthia Harumi , Tatarunas Angélica Cecilia , Valente Neusa Sakai , Michalany Nílceo
Published: March 2008

O hemangiopericitoma canino é uma neoplasia cutânea relativamente comum, que surge principalmente nos membros. As formas de terapia mais indicadas são a amputação; ressecção local e radioterapia, sendo freqüente a ocorrência de recidivas (GOLDSCHIMIDT & SHOFER, 1992). Os registros de seis cães atendidos no Serviço de Técnica Cirúrgica do Hospital Veterinário da Faculdade de Medicina Veterinária da Universidade de São Paulo foram revisados no período de julho de 1994 a julho de 1996. Foram avaliados os dados referentes à formação cutânea, técnica de retalho cutâneo utilizada, e evolução pós-operatória dos animais. Os cães pertenciam a diferentes raças, sendo três machos e três fêmeas com idade média de 9 anos. Em cinco cães, as massas neoplásicas surgiram nos membros e, em um cão, na região perineal. As técnicas de retalhos cutâneos utilizadas foram a H-plastia (2), retalho por avanço pediculado simples(1), retalho por transposição(2) e W-plastia(1). A cicatrização da pele levou de 10 a 15 dias com sobrevivência de 100% do retalho em cinco cães e 89% do retalho em um cão. Um dos animais veio a óbito 15 meses após a cirurgia devido a causas não relacionadas à neoplasia. Não ocorreu recidiva num intervalo que variou de 4 a 20 meses, desde a cirurgia até a presente data. A excisão cirúrgica do hemangiopericitoma canino com amplas margens de segurança, parece ser uma forma de terapia eficiente, uma vez que não ocorreram recidivas. O domínio das técnicas de retalhos cutâneos tem permitido tal procedimento, pois não há o receio de não se conseguir reconstruir os tecidos locais. A recuperação dos animais é mais rápida e o custo é menor em relação às outras formas de terapia.
Nível nutricional único ou sequencial em dietas para leitões desmamados
Authors: Pruss Cezar Vlademir , Silveira João Carlos Gauer da , Zanella Irineo
Published: March 2008

Objetivando estudar os efeitos de níveis nutricionais em dietas para leitões na fase inicial (28 a 70 dias de idade), sobre o consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA) e custo do quilograma de leitões vivo produzido (CQL), foi conduzido um experimento no Departamento de Zootecnia da UFSM, no período entre outubro e novembro/93. Foram utilizados 24 leitões mestiços (Landrace x Largo White), desmamados aos 28 dias de idade, distribuídos em gaiolas-creche. Foi utilizado o delineamento inteiramente casualizado, com 3 tratamentos e 8 repetições. Os tratamentos testados foram: T1- Ração A (28 a 70 dias de idade) ;T2-Ração A (28 a 42 dias) e Ração B (42 a 70 dias); T3 - Ração A (28 a 42 dias), Ração B (42 a 56 dias) e Ração C (56 a 70 dias). As rações foram formuladas para conter: 20, 18 e 16% de PB,3240, 3250 e 3260kcal EM/kg, 0,79, 0,69 e 0,59% de Ca e 0,64, 0,59 e 0,49% de P, respectivamente para as rações A, B e C. Os resultados obtidos foram: CR = 45,67, 46,19 e 45,49kg/animal; GP = 23,85, 23,62 e 22,69kg/animal; CA = 1,92, 1,96 e 2,00 e para CQL 0,4762, 0,4571 e 0,4569 US$/kg, respectivamente para os tratamentos T1, T2 e T3. A análise de variância não mostrou diferença significativa (P > 0,05) entre os tratamentos para nenhum dos parâmetros estudados. Conclui-se que o desempenho dos leitões, no período 28 a 70 dias de idade, não foram influenciados pelos níveis nutricionais testados.