bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Cost Sharing on Access to Care among Childless Adults
Authors: Guy Jr. Gery P.
Published: September 2010

Objectives. To analyze the impact of public health insurance expansions and the use of enrollee cost sharing on insurance status and receipt of clinically indicated preventive screenings and physician services.

Data Source. This study uses Behavioral Risk Factor Surveillance System (BRFSS) data from 1997 to 2007.

Study Design. This study uses multivariate difference‐in‐difference logistic regression modeling of pooled cross‐sectional time series data. The effect of the expansions on insurance status and access to care is identified by cross‐state variation in program implementation, as well as cross‐state and within‐state variation in program eligibility criteria over time.

Principal Findings. Childless adult expansions, regardless of cost‐sharing levels, reduced uninsurance rates and decreased the likelihood that childless adults needed to see a physician but did not because of cost. Expansions with traditional public insurance cost‐sharing requirements increased the use of preventive screenings, while expansions with increased cost‐sharing requirements did not.

Conclusions. Cost‐sharing requirements did not have an impact on the ability to see a physician when needed, but they played an important role in the utilization of preventive services. Expanding public health insurance to low‐income, childless adults presents a promising policy opportunity, but there are trade‐offs between the efficiencies obtained through increased cost sharing and the potential inefficiencies due to the lower use of preventive services.
Bioinformatics approach to identifying molecular biomarkers and networks in multiple sclerosis
Authors: Satoh Jun‐ichi
Published: September 2010

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) white matter mediated by an autoimmune process triggered by a complex interplay between genetic and environmental factors, in which the precise molecular pathogenesis remains to be comprehensively characterized. The global analysis of genome, transcriptome, proteome and metabolome, collectively termed omics, promotes us to characterize the genome‐wide molecular basis of MS. However, as omics studies produce high‐throughput experimental data at one time, it is often difficult to find out the meaningful biological implications from huge datasets. Recent advances in bioinformatics and systems biology have made major breakthroughs by illustrating the cell‐wide map of complex molecular interactions with the aid of the literature‐based knowledgebase of molecular pathways. The integration of omics data derived from the disease‐affected cells and tissues with underlying molecular networks provides a rational approach not only to identifying the disease‐relevant molecular markers and pathways, but also to designing the network‐based effective drugs for MS. (Clin. Exp. Neuroimmunol. doi: 10.1111/j.1759‐1961.2010.00013.x, 2010)
Biodiesel Effects on Influencing Parameters of Brake Fuel Conversion Efficiency in a Medium Duty Diesel Engine
Authors: Bittle Joshua A. , Younger Jesse K. , Jacobs Timothy J.
Published: September 2010

Biodiesel remains an alternative fuel of interest for use in diesel engines. A common characteristic of biodiesel, relative to petroleum diesel, is a lowered heating value (or per mass energy content of the fuel). For same torque engine comparisons, the lower heating value translates into a higher brake specific fuel consumption (amount of fuel consumed per unit of power produced). The efficiency at which fuel energy converts into work energy, however, may remain unchanged. In this experimental study, evaluating nine unique engine operating conditions, the brake fuel conversion efficiency (an assessor of fuel energy to work energy efficiency) remains unchanged between 100% petroleum diesel fuel and 100% biodiesel fuel (palm olein) at all conditions, except for high load conditions. Several parameters may affect the brake fuel conversion efficiency, including heat loss, mixture properties, pumping work, friction, combustion efficiency, and combustion timing. This article describes a study that evaluates how the aforementioned parameters may change with the use of biodiesel and petroleum diesel, and how these parameters may result in differences in the brake fuel conversion efficiency.
Onset of Nonlinearity in the Elastic Bending of Blocks
Authors: Destrade M. , Gilchrist M. D. , Murphy J. G.
Published: September 2010

The classical flexure problem of nonlinear incompressible elasticity is revisited assuming that the bending angle suffered by the block is specified instead of the usual applied moment. The general moment-bending angle relationship is then obtained and is shown to be dependent on only one nondimensional parameter: the product of the aspect ratio of the block and the bending angle. A Maclaurin series expansion in this parameter is then found. The first-order term is proportional to μ, the shear modulus of linear elasticity; the second-order term is identically zero because the moment is an odd function of the angle; and the third-order term is proportional to μ(4β−1), where β is the nonlinear shear coefficient, involving third-order and fourth-order elasticity constants. It follows that bending experiments provide an alternative way of estimating this coefficient and the results of one such experiment are presented. In passing, the coefficients of Rivlin’s expansion in exact nonlinear elasticity are connected to those of Landau in weakly (fourth-order) nonlinear elasticity.
Effects of Inlet Preswirl and Cell Diameter and Depth on Honeycomb Seal Characteristics
Authors: Yan Xin , Li Jun , Feng Zhenping
Published: September 2010

Three-dimensional Reynolds-averaged Navier–Stokes solutions are employed to investigate the discharge and total temperature increase characteristics of the stepped labyrinth seal with honeycomb land. First, the relations between the windage heating number and the circumferential Mach number at different Reynolds numbers for different honeycomb seals are calculated and compared with the experimental data. The obtained numerical results show that the present three-dimensional periodic model can properly predict the total temperature increase in honeycomb seals. Then, a range of pressure ratios, three inlet preswirl ratios, four sizes of honeycomb cell diameter, and nine sizes of cell depth are selected to investigate the influence of inlet preswirl ratios and honeycomb geometry sizes on the discharge and total temperature increase characteristics of the stepped labyrinth seal. It shows that the leakage rate increases with the increase in cell diameter, and the cell depth has a strong influence on the discharge behavior. However, the influence of the inlet preswirl on the leakage rate is found to be little in the present study. For the total temperature increase characteristic, the inlet preswirl ratio and pressure ratio have more pronounced influence than those of cell depth and diameter. Furthermore, the relations between the leakage rate and cell depth and diameter, as well as the relations between the windage heating power and cell depth and diameter, are not monotonic functions if the pressure ratio is kept constant.
Constrained Design Optimization of Rotor-Tilting Pad Bearing Systems
Authors: Untaroiu Costin D. , Untaroiu Alexandrina
Published: September 2010

Design of a rotor-bearing system is a challenging task due to various conflicting design requirements, which should be fulfilled. This study considers an automatic optimization approach for the design of a rotor supported on tilting-pad bearings. A numerical example of a rotor-bearing system is employed to demonstrate the merits of the proposed design approach. The finite element method is used to model the rotor-bearing system, and the dynamic speed-dependent coefficients of the bearing are calculated using a bulk flow code. A number of geometrical characteristics of the rotor simultaneously with the parameters defining the configuration of tilting pad bearings are considered as design variables into the automatic optimization process. The power loss in bearings, stability criteria, and unbalance responses are defined as a set of objective functions and constraints. The complex design optimization problem is solved using heuristic optimization algorithms, such as genetic, and particle-swarm optimization. Whereas both algorithms found better design solutions than the initial design, the genetic algorithms exhibited the fastest convergence. A statistical approach was used to identify the influence of the design variables on the objective function and constraint measures. The bearing clearances, preloads and lengths showed to have the highest influence on the power loss in the chosen design space. The high performance of the best solution obtained in the optimization design suggests that the proposed approach has good potential for improving design of rotor-bearing systems encountered in industrial applications.
On the Performance of Porous Sound Absorbent Material in High Temperature Applications
Authors: Giese Frank , Ries Hans-Christoph , Eigenbrod Christian
Published: September 2010

This paper discusses the use of novel porous sound absorbent ceramic tiles as heat shields in combustion chambers with respect to their sound absorption. For this purpose, a theory describing the bulk properties of a homogeneous porous absorber layer was combined with a transfer matrix approach to account for the temperature gradient within the absorber. By means of a high temperature scenario, the maximum absorption performance and the required microscale properties of the absorber are presented.
Population dynamics of an Egyptian desert shrub, Thymelaea hirsuta
Authors: El-Keblawy Ali , Shaltout K. H. , Lovett-Doust J. , Ramadan A.
Published: September 2010

Natural populations of the evergreen shrub, Thymelaea hirsuta (L.) Endl., were studied over 6 years at five desert habitats, in terms of seedling recruitment and adult survival and as a function of plant size and gender class. Habitat and time significantly influenced mortality of both reproductive and non-reproductive plants. Plant size also significantly affected adult mortality. Seedling recruitment varied significantly with habitat and year and approached zero some years. Significant among-year and among-population variation in population growth rates were observed over the 6 years of study, and all populations declined in size (ranging from −1.7% per year at the coastal dune site to −10.9% per year at the inland plateau site). Spearman rank correlation analysis between habitats ranked according to a north–south gradient and demographic variables indicates that this gradient is associated with a pattern of lower seedling emergence and survival and a lower population growth rate and greater mortality for all size-classes of Thymelaea plants. In experimental botanic garden plots, germination of seed collected from five natural populations, and seedling survival in the following year were assessed under conditions of high, medium, and low seedling density. Seedling emergency differed significantly according to maternal habitat. With regular watering, seeding survival to one year was 72% (averaged across habitats and densities). This compares with 64% for seedlings grown at the highest density, suggesting that the intense mortality observed under field conditions is more likely to be a result of water shortage than intraspecific competition. Key words: Egyptian desert, Thymelaea hirsuta, germination and establishment, seedlings, recruitment, competition, population growth rate.
Potential effects of granivores on old field succession
Authors: Reader R. J.
Published: September 2010

The author of a literature review tentatively concluded that preferential predation on large seeds of late sueccssional species retards plant succession. To test this tentative conclusion for old fields, I determined whether seed predators (i.e., granivores) removed more seeds of later successional species (trees) than earlier successional species (herbs). Seeds of three herbs (Hypericum perforatum L., Centaurea nigra L., Tragopogon dubius Scop.) and three trees (Betula papyrifera Marshall, Fraxinus americana L.. Acer saccharum Marshall) were glued to the ends of fish lines and exposed to granivory for 10 months in each of four old fields. More tree seeds of all sizes (0.53–75.9 mg) disappeared than did seeds of the herb with the smallest seeds (0.11 mg). This result indicates that granivory may indeed retard old field succession. However, about equal numbers of seeds disappeared for the two herbs with larger seeds (2.3–11.6 mg) and two trees with even larger seeds (34.1–75.9 mg). Therefore, granivory may not affect old field succession when both early and later successional species have seeds larger than some critical minimum size. Fewer seeds of the tree with the smallest seeds (0.53 mg) disappeared than did seeds of the two herbs with larger seeds (2.3–11.6 mg). This result implies that granivores have the potential to hasten old field succession for trees with small seeds. Collectively, results of this study suggest that there is more than just one potential effect of granivores on old field succession. Key words: seed predation, seed size, succession, old field.
SEMI-AUTONOMOUS NEEDLE-POSITIONING DEVICE FOR PERCUTANEOUS NEPHROLITHOTOMY PROCEDURES
Authors: CONRADIE JEAN-PIERRE , SCHEFFER CORNIE , SCHREVE KRISTIAAN , ZARRABI AMIR
Published: September 2010

At present, manual needle-positioning techniques known as "triangulation" and "keyhole surgery" are implemented during percutaneous nephrolithotomy (PCNL) to gain initial kidney access. These techniques do not ensure correct needle placement inside the kidney, resulting in multiple needle punctures, unnecessary hemorrhage, excessive radiation exposure to all involved and increased surgery time. A cost-effective fluoroscopy-guided needle-positioning system is proposed for aiding urologists in gaining accurate and repeatable kidney calyx access. Guidance is realized by modeling a C-arm fluoroscopic system as an adapted pinhole camera model and utilizing stereovision principles on an image pair. Targeting is realized with the aid of a graphical user interface operated by the surgeon. An average target registration error of 2.5 mm (SD = 0.8 mm) was achieved in a simulated environment. Similar results were achieved in the operating room environment with successful needle access in two in-vitro porcine kidneys.
Meal patterns and hypothalamic NPY expression during chronic social stress and recovery
Authors: Melhorn Susan J. , Krause Eric G. , Scott Karen A. , Mooney Marie R. , Johnson Jeffrey D. , Woods Stephen C. , Sakai Randall R.
Published: September 2010

In the present study, we examined meal patterns during and after exposure to the visible burrow system (VBS), a rodent model of chronic social stress, to determine how the microstructure of food intake relates to the metabolic consequences of social subordination. Male Long-Evans rats were housed in mixed-sex VBS colonies (4 male, 2 female) for 2 wk, during which time a dominance hierarchy formed [1 dominant male (DOM) and 3 subordinate males (SUB)], and then male rats were individually housed for a 3-wk recovery period. Controls were individually housed with females during the 2-wk VBS period and had no changes in ingestive behavior compared with a habituation period. During the hierarchy-formation phase of VBS housing, DOM and SUB had a reduced meal frequency, whereas SUB also had a reduced meal size. However, during the hierarchy-maintenance phase of VBS housing, DOM meal patterns did not differ from controls, whereas SUB continued to display a reduced food intake via less frequent meals. During recovery, DOM had comparable meal patterns to controls, whereas SUB had an increased meal size. Hypothalamic neuropeptide Y (NPY) mRNA levels were not different between these groups during the experimental period. Together, the results suggest that exposure to chronic social stress alters ingestive behavior both acutely and in the long term, which may influence the metabolic changes that accompany bouts of stress and recovery; however, these differences in meal patterns do not appear to be mediated by hypothalamic NPY.
Output Regulation Problem for Differentiable Families of Linear Systems
Authors: Compta Albert , Ferrer Josep , Peña Marta
Published: September 2010

Given a family of linear systems depending on a parameter varying in a differentiable manifold, we obtain sufficient conditions for the existence of a (global or local) differentiable family of controllers solving the output regulation problem for the given family. Moreover, we construct it when these conditions hold.
Rumination Mediates the Relationship between Infant Temperament and Adolescent Depressive Symptoms
Authors: Mezulis Amy H. , Priess Heather A. , Hyde Janet Shibley
Published: September 2010

This study examined prospective associations between negative emotionality, rumination, and depressive symptoms in a community sample of 301 youths (158 females) followed longitudinally from birth to adolescence. Mothers reported on youths' negative emotionality (NE) at age 1, and youths self-reported rumination at age 13 and depressive symptoms at ages 13 and 15. Linear regression analyses indicated that greater NE in infancy was associated with more depressive symptoms at age 15, even after controlling for child gender and depressive symptoms at age 13. Moreover, analyses indicated that rumination significantly mediated the association between infancy NE and age 15 depressive symptoms in the full sample. When analyzed separately by gender, however, rumination mediated the relationship between NE and depressive symptoms for girls but not for boys. The results confirm and extend previous findings on the association between affective and cognitive vulnerability factors in predicting depressive symptoms and the gender difference in depression in adolescence, and suggest that clinical interventions designed to reduce negative emotionality may be useful supplements to traditional cognitive interventions for reducing cognitive vulnerability to depression.
Nucleotide Excision Repair Gene Expression after Cisplatin Treatment in Melanoma
Authors: Bowden Nikola A. , Ashton Katie A. , Avery-Kiejda Kelly A. , Zhang Xu Dong , Hersey Peter , Scott Rodney J.
Published: September 2010

Two of the hallmark features of melanoma are its development as a result of chronic UV radiation exposure and the limited efficacy of cisplatin in the disease treatment. Both of these DNA-damaging agents result in large helix-distorting DNA damage that is recognized and repaired by nucleotide excision repair (NER). The aim of this study was to examine the expression of NER gene transcripts, p53, and p21 in melanoma cell lines treated with cisplatin compared with melanocytes. Basal expression of all genes was greater in the melanoma cell lines compared with melanocytes. Global genome repair (GGR) transcripts showed significantly decreased relative expression (RE) in melanoma cell lines 24 hours after cisplatin treatment. The basal RE of p53 was significantly higher in the melanoma cell lines compared with the melanocytes. However, induction of p53 was only significant in the melanocytes at 6 and 24 hours after cisplatin treatment. Inhibition of p53 expression significantly decreased the expression of all the GGR transcripts in melanocytes at 6 and 24 hours after cisplatin treatment. Although the RE levels were lower with p53 inhibition, the induction of the GGR genes was very similar to that in the control melanocytes and increased significantly across the time points. The findings from this study revealed reduced GGR transcript levels in melanoma cells 24 hours after cisplatin treatment. Our findings suggest a possible mechanistic explanation for the limited efficacy of cisplatin treatment and the possible role of UV light in melanoma. Cancer Res; 70(20); 7918–26. ©2010 AACR.
BNP7787-Mediated Modulation of Paclitaxel- and Cisplatin-Induced Aberrant Microtubule Protein Polymerization In vitro
Authors: Parker Aulma R. , Petluru Pavankumar N. , Wu Meizhen , Zhao Min , Kochat Harry , Hausheer Frederick H.
Published: September 2010

Taxane and platinum drugs are important agents in the treatment of cancer and have shown activity against a variety of tumors, including ovarian, breast, and lung cancer, either as single agents or in combination with other chemotherapy drugs. However, a serious and prevalent side effect of taxane (docetaxel and all formulations/derivatives of paclitaxel) and platinum (cisplatin, carboplatin, and oxaliplatin) agents is dose-limiting chemotherapy-induced peripheral neuropathy (CIPN). CIPN can result in treatment delays, dose modifications, and, in severe cases, discontinuation of chemotherapy. Consequently, effective treatments for CIPN are needed. Dimesna (BNP7787; Tavocept TM; disodium 2,2′-dithio-bis-ethanesulfonate) is an investigational drug that is undergoing international clinical development as a treatment that is coadministered with first-line taxane and platinum combination chemotherapy in patients with inoperable advanced primary adenocarcinoma of the lung. BNP7787 is currently being developed with the objective of increasing the survival of cancer patients receiving taxane- and/or cisplatin-based chemotherapy. Additional data indicate that BNP7787 may also protect against common and serious chemotherapy-induced toxicities, including chemotherapy-induced anemia, nausea, emesis, nephrotoxicity, and neuropathy, without interfering with antitumor activity of the chemotherapeutic agent(s). Studies herein show that BNP7787 prevents aberrant microtubule protein (MTP) polymerization that is caused by exposure of MTP to paclitaxel or cisplatin. BNP7787 modulates paclitaxel-induced hyperpolymerization of MTP in a dose-dependent manner, and mesna, an in vivo metabolite of BNP7787, protects against time-dependent cisplatin-induced inactivation of MTP. We propose that interactions between BNP7787 and MTP may play a role in BNP7787-mediated protection against CIPN. Mol Cancer Ther; 9(9); 2558–67. ©2010 AACR.
Restoration of Knee Volume Using Selected Arthroscopic Releases
Authors: Dragoo Jason L. , Miller Matthew D. , Vaughn Zackary D. , Schmidt Joshua D. , Handley Elizabeth
Published: September 2010

Background

Inflammation and subsequent fibrosis, adhesions, or plicae may limit normal capsular compliance and decrease volume capacity of the knee.

Hypothesis

Patients with fibrosis, anterior interval scarring, adhesions, or palpable painful plicae will have decreased knee volumes when compared to controls, and selective arthroscopic releases will restore volume to normal levels.

Study Design

Descriptive laboratory study and cohort study; Level of evidence, 2.

Methods

In part I, knee volume and pressure were recorded in 14 fresh-frozen human cadaveric knees, and the maximum volume capacity was identified before capsular disruption. In part II, 49 patients undergoing arthroscopy were divided into 2 groups based on intraoperative volume assessment at 50 mm H2O pressure: group 1 (n = 20) with normal volume (<1 standard deviation below the mean established in part I) and group 2 (n = 29) knees with deficient volume (>1 standard deviation below mean). Group 2 underwent volume-changing procedures such as lysis of adhesions, anterior interval release, and plica resections, while group 1 underwent volume-neutral procedures including meniscal or chondral surgery. The knee volume was then reassessed after arthroscopy.

Results

The average volume capacity of the knees in the cadaveric study was 87.5 ± 21.7 mL (range, 50-120 mL). There was no statistical difference between the presurgical (98.9 ± 29.8 mL) and postsurgical volumes (99.4 ± 29.1 mL) in group 1; P = .65. The presurgical volume in group 2 (46.1 ± 13.0 mL) was significantly lower than group 1 (P = .001). The group 2 volume increased to 78.5 ± 24.2 mL after surgery (P = .001), with an average change in volume of 75.5%. The mean change in volume after surgery was significantly greater in group 2 (32.3 mL) versus group 1 (0.45 mL) (P = .001). At 1-year follow-up, the mean Tegner score in the volume-compromised group 2 increased from 2.0 ± 1.4 preoperatively to 4.0 ± 2.0 postoperatively (P = .01), the Lysholm score increased from 45.0 ± 24.0 preoperatively to 76.8 ± 25.4 postoperatively (P = .003), and the average Short Form-12 quality of life score increased from 32.4 ± 8.7 preoperatively to 45.0 ± 11.0 postoperatively (P = .005).

Conclusions

The average volume of the human knee in this study was between 65 and 110 mL (±1 standard deviation of mean of 87.5 mL). Although patients with chronic knee pain may have pain from multiple sources, some may have diminished knee volume, and selected arthroscopic releases can restore knee volume to near-normal levels.
On the deformation of orthotropic Cosserat elastic cylinders
Authors: Ieşan D. , Scalia A.
Published: September 2010

In this article we are concerned with the linear theory of inhomogeneous and orthotropic Cosserat elastic solids. We study the equilibrium problem for a right cylinder which is subjected to body loads, surface tractions on the lateral surface, and to resultant forces and resultant moments on the ends. The constitutive coefficients are independent of the axial coordinate. First, we study the plane strain problem and establish the solution of the extension and torsion problem. Then, we present a method to derive the solution to the problem of loaded cylinders. The method is new even in the case of homogeneous and isotropic Cosserat elastic bodies. By this method the solution of the three-dimensional problem is reduced to the study of some plane problems. The method is applied to investigate the deformation of a circular cylinder subjected to a uniform load.
AT1 receptor and NAD(P)H oxidase mediate angiotensin II-stimulated antioxidant enzymes and mitogen-activated protein kinase activity in the rat hypothalamus
Authors: Silva José , Pastorello Mariella , Arzola Jorge , Zavala Lida E. , De Jesús Sara , Varela Maider , Matos María Gabriela , del Rosario Garrido María , Israel Anita
Published: September 2010

Introduction. Angiotensin II (AngII) regulates blood pressure and water and electrolyte metabolism through the stimulation of NAD(P)H oxidase and production of reactive oxygen species (ROS) such as O2—, which is metabolised by superoxide dismutase, catalase and glutathione peroxidase. We assessed the role of AT1 and AT2 receptors, NAD(P)H oxidase and protein kinase C (PKC) in Ang II-induced sodium and water excretion and their capacity to stimulate antioxidant enzymes in the rat hypothalamus, a brain structure known to express a high density of AngII receptors.

Materials and methods. Male Sprague—Dawley rats were intracerebroventricularly (ICV) injected with AngII and urinary sodium and water excretion was assessed. Urine sodium concentration was determined using flame photometry. After decapitation the hypothalamus was microdissected under stereomicroscopic control. Superoxide dismutase, catalase and glutathione peroxidase activity were determined spectrophotometrically and extracellular signal-regulated kinase (ERK1/2) activation was analysed by Western blot.

Results. AngII-ICV resulted in antidiuresis and natriuresis. ICV administration of losartan, PD123319, apocynin and chelerythrine blunted natriuresis. In hypothalamus, AngII increased catalase, superoxide dismutase and glutation peroxidase activity and ERK1/2 phosphorylation. These actions were prevented by losartan, apocynin and chelerythrine, and increased by PD123319.

Conclusions. AT 1 and AT2 receptors, NAD(P)H oxidase and PKC pathway are involved in the regulation of hydromineral metabolism and antioxidant enzyme activity induced by AngII.
South African Female Principals’ Career Paths: Understanding the Gender Gap in Secondary School Management
Authors: Moorosi Pontso
Published: September 2010

This article reports on data from a larger scale study exploring female principals’ experiences of their career route to the principalship of secondary schools in South Africa. To understand these experiences, the study used an analytical framework that identifies three phases principals go through on their career route, namely: anticipation, acquisition and performance. The framework suggests that women experience more obstacles than men on their career route and their experiences are influenced by personal, organizational and social factors. These factors manifest in social practices within and outside schools and affect women across the three phases of the career route. Central to these experiences, is the underlying male norm of who is more appropriate for secondary school principalship.
TEL-AML1 regulation of survivin and apoptosis via miRNA-494 and miRNA-320a
Authors: Diakos Christofer , Zhong Sheng , Xiao Yuanyuan , Zhou Mi , Vasconcelos Gisele M. , Krapf Gerd , Yeh Ru-Fang , Zheng Shichun , Kang Michelle , Wiencke John K. , Pombo-de-Oliveira Maria S. , Panzer-Grümayer Renate , Wiemels Joseph L.
Published: September 2010

There is increasing evidence that miRNA and transcription factors interact in an instructive fashion in normal and malignant hematopoiesis. We explored the impact of TEL-AML1 (ETV6-RUNX1), the most common fusion protein in childhood leukemia, on miRNA expression and the leukemic phenotype. Using RNA interference, miRNA expression arrays, and quantitative polymerase chain reaction, we identified miRNA-494 and miRNA-320a to be up-regulated upon TEL-AML1 silencing independently of TEL expression. Chromatin immunoprecipitation analysis identified miRNA-494 as a direct miRNA target of the fusion protein TEL-AML1. Using bioinformatic analysis as well as functional luciferase experiments, we demonstrate that survivin is a target of the 2 miRNAs. miRNA-494 and miRNA-320a were introduced to the cells by transfection and survivin expression determined by Western blot analysis. These miRNAs blocked survivin expression and resulted in apoptosis in a similar manner as TEL-AML1 silencing by itself; this silencing was also shown to be Dicer-dependent. miRNAs-494 and -320a are expressed at lower levels in TEL-AML1+ leukemias compared with immunophenotype-matched nonTEL-AML1 acute lymphoblastic leukemia subtypes, and within TEL-AML1+ leukemias their expression is correlated to survivin levels. In summary our data suggest that TEL-AML1 might exert its antiapoptotic action at least in part by suppressing miRNA-494 and miRNA-320a, lowering their expression causing enhanced survivin expression.
Optimising the management of pulmonary arterial hypertension patients: emergency treatments
Authors: Delcroix M. , Naeije R.
Published: September 2010

Pulmonary arterial hypertension (PAH) is a rare and potentially fatal disease whose management is usually restricted to a few specialised centres. As patients do not necessarily live in the neighbourhood of these centres, daily care and emergencies have to be delegated to first and second lines. Treatment guidelines do not usually provide recommendations for acute emergency situations as evidence is scarce. This short review provides a description of our therapeutic protocols based on available data.

A model of transmural organisation of care for PAH patients, currently applied in Belgium, is described. Thereafter, based on an analysis of the reasons of death in the PAH population, a review of the main emergencies is provided. Cardiac arrest and resuscitation, decompensated right heart failure, respiratory failure, arrhythmia, pericardial effusion, haemoptysis, surgery and drug-related adverse events will be discussed successively.

Case reports showing the precariousness of PAH patients will enforce our thesis of the need for optimal patient management organisation.
Can the Non-pneumatic Anti-Shock Garment (NASG) reduce adverse maternal outcomes from postpartum hemorrhage? Evidence from Egypt and Nigeria
Authors: Mourad-Youssif Mohammed , Ojengbede Oladosu A , Meyer Carinne D , Fathalla Mohammad , Morhason-Bello Imran O , Galadanci Hadiza , Camlin Carol , Nsima David , al Hussaini Tarek , Butrick Elizabeth , Miller Suellen
Published: September 2010

Background

Postpartum hemorrhage (PPH) is the leading cause of maternal mortality and severe maternal morbidity. The Non-pneumatic Anti-Shock Garment (NASG), a first-aid lower-body compression device, may decrease adverse outcomes from obstetric hemorrhage. This article is the first to report the effect of the NASG for PPH.

Methods

This pre-intervention/NASG study of 854 women was conducted in four referral facilities in Nigeria and two in Egypt between 2004-2008. Entry criteria were women with PPH due to uterine atony, retained placenta, ruptured uterus, vaginal or cervical lacerations or placenta accreta with estimated blood loss of ≥ 750 mL and one clinical sign of shock. Differences in demographics, conditions on study entry, treatment and outcomes were examined. The Wilcoxon rank-sum test and relative risks with 95% confidence intervals were calculated for primary outcomes - measured blood loss, emergency hysterectomy, mortality, morbidity (each individually), and a combined variable, "adverse outcomes", defined as severe morbidity and mortality. A multiple logistic regression model was fitted to test the independent association between the NASG and the combined severe morbidity and mortality outcome.

Results

Measured blood loss decreased by 50% between phases; women experienced 400 mL of median blood loss after study entry in the pre-intervention and 200 mL in the NASG phase (p < 0.0001). As individual outcomes, mortality decreased from 9% pre-intervention to 3.1% in the NASG phase (RR 0.35, 95% CI 0.19-0.62); severe morbidity decreased from 4.2% to 1%, in the NASG phase (RR 0.24, 95% CI 0.09-0.67). As a combination, "adverse outcomes," decreased from 12.8% to 4.1% in the NASG phase (RR 0.32, 95% CI 0.19-0.53). In a multiple logistic regression model, the NASG was associated with the combined outcome of severe maternal morbidity and mortality (OR 0.42, 95% CI 0.18-0.99).

Conclusion

In this non-randomized study, in which bias is inherent, the NASG showed promise for reducing blood loss, emergency hysterectomy, morbidity and mortality associated with PPH in referral facilities in Egypt and Nigeria.
The Nordic maintenance care program: what are the indications for maintenance care in patients with low back pain? A survey of the members of the Danish Chiropractors' Association
Authors: Hansen Signe F , S Laursen Anne L , Jensen Tue S , Leboeuf-Yde Charlotte , Hestbæk Lise
Published: September 2010

Background

Maintenance care (MC) is relatively commonly used among chiropractors. However, factual information is needed on its indications for use.

Objectives

This study had two objectives: 1) to describe which role patients' past history and treatment outcome play in chiropractors' decision to use MC in patients with low back pain, 2) to investigate if the chiropractors' clinical/educational background has an effect on the frequency of using MC and their indications for use of MC.

Method

An anonymous questionnaire was sent to all 413 chiropractors practising in Denmark. Its main part consisted of 3 sets of 4 questions relating to one basic case of low back pain. For each case, the chiropractors were asked if they would use MC as they self-defined the term (no/perhaps/yes). There were questions also on gender, age, educational and clinical background, and on the number of MC patients seen by these chiropractors. Their decision to recommend MC was reported. Associations between the demographic variables and 1) the frequency of MC-use and 2) their indications for use of MC were tested through multivariate analysis.

Results

The response rate was 72%. Non-indications for MC were: 1) a good outcome combined with no previous events, or 2) a past history of LBP and gradual worsening with treatment. Indications for MC were a good outcome combined with a previous history of low back pain between once a month and once a year. The mean proportion of MC patients per week were 22% (SD 19), ranging from 0% to 100%. The use of MC was highest among experienced chiropractors, those who were educated in North America, and clinic owners. However, in Denmark most chiropractors graduated before 1999, are educated abroad, whereas most chiropractors thereafter are educated in Denmark. Therefore, we cannot conclude whether this difference relates to education or years of experience. There were no associations detected between demographic variables and the indications for MC.

Conclusions

There is relatively high consensus on when MC should and should not be used. A history of prior low back pain combined with a positive response to treatment encourages the use of MC, whereas no previous history of back pain or a worsening of symptoms discourages the use of MC. There seems to be a difference in the proportional use of MC between chiropractors with more experience educated in North America and those with less experience educated in Denmark.
Identifying experimental surrogates for Bacillus anthracis spores: a review
Authors: Greenberg David L , Busch Joseph D , Keim Paul , Wagner David M
Published: September 2010

Bacillus anthracis, the causative agent of anthrax, is a proven biological weapon. In order to study this threat, a number of experimental surrogates have been used over the past 70 years. However, not all surrogates are appropriate for B. anthracis, especially when investigating transport, fate and survival. Although B. atrophaeus has been widely used as a B. anthracis surrogate, the two species do not always behave identically in transport and survival models. Therefore, we devised a scheme to identify a more appropriate surrogate for B. anthracis. Our selection criteria included risk of use (pathogenicity), phylogenetic relationship, morphology and comparative survivability when challenged with biocides. Although our knowledge of certain parameters remains incomplete, especially with regards to comparisons of spore longevity under natural conditions, we found that B. thuringiensis provided the best overall fit as a non-pathogenic surrogate for B. anthracis. Thus, we suggest focusing on this surrogate in future experiments of spore fate and transport modelling.
Introductory Life Science Mathematics and Quantitative Neuroscience Courses
Authors: Duffus Dwight , Olifer Andrei
Published: September 2010

We describe two sets of courses designed to enhance the mathematical, statistical, and computational training of life science undergraduates at Emory College. The first course is an introductory sequence in differential and integral calculus, modeling with differential equations, probability, and inferential statistics. The second is an upper-division course in computational neuroscience. We provide a description of each course, detailed syllabi, examples of content, and a brief discussion of the main issues encountered in developing and offering the courses.
Bioinformatics and the Undergraduate Curriculum
Authors: Maloney Mark , Parker Jeffrey , LeBlanc Mark , Woodard Craig T. , Glackin Mary , Hanrahan Michael
Published: September 2010

Recent advances involving high-throughput techniques for data generation and analysis have made familiarity with basic bioinformatics concepts and programs a necessity in the biological sciences. Undergraduate students increasingly need training in methods related to finding and retrieving information stored in vast databases. The rapid rise of bioinformatics as a new discipline has challenged many colleges and universities to keep current with their curricula, often in the face of static or dwindling resources. On the plus side, many bioinformatics modules and related databases and software programs are free and accessible online, and interdisciplinary partnerships between existing faculty members and their support staff have proved advantageous in such efforts. We present examples of strategies and methods that have been successfully used to incorporate bioinformatics content into undergraduate curricula.
Interdisciplinary Training in Mathematical Biology through Team-based Undergraduate Research and Courses
Authors: Miller Jason E. , Walston Timothy
Published: September 2010

Inspired by BIO2010 and leveraging institutional and external funding, Truman State University built an undergraduate program in mathematical biology with high-quality, faculty-mentored interdisciplinary research experiences at its core. These experiences taught faculty and students to bridge the epistemological gap between the mathematical and life sciences. Together they created the infrastructure that currently supports several interdisciplinary courses, an innovative minor degree, and long-term interdepartmental research collaborations. This article describes how the program was built with support from the National Science Foundation's Interdisciplinary Training for Undergraduates in Biology and Mathematics program, and it shares lessons learned that will help other undergraduate institutions build their own program.
E. Virginia Armbrust
Authors: Hoopes Laura L. Mays
Published: September 2010

Note from the Editor

Educator Highlights for CBE-LSE show how professors at different kinds of institutions educate students in life sciences with inspiration and panache. If you have a particularly creative teaching portfolio yourself, or if you want to suggest someone else to be profiled, please e-mail Laura Hoopes at Pomona College, lhoopes@pomona.edu .
Can I Drive My Car from Its Form to Its Movement?
Authors: Bourbon Brett
Published: September 2010

The academic dominance of cultural studies and the increasing interest and significance of cultural conflict in our world has encouraged various theories of culture, the most pervasive being theories of transculture and hybrid cultural forms and entities. In this guest column, Bourbon argues that all such trans theories are fundamentally flawed and distort the very idea of culture. His essay analyzes the concept of transobjects and transcultures, looking both at the assumptions supporting such objects and ideas and at their explanatory uses. This discussion leads to one on the relationship between texts and contexts. Most cultural theories, and all transcultural theories, confuse the relationship between texts and contexts, specifically misusing the idea of the conditions of possibility, while relying on various forms of personification. Bourbon both criticizes these ideas and also offers a more modest idea of culture, along with specific suggestions on how to study and understand what we call “products of culture,” including fictions and ourselves.
In Vivo Diffuse Optical Tomography and Fluorescence Molecular Tomography
Authors: Li Mingze , Zhang Yonghong , Bai Jing
Published: September 2010

Diffuse optical tomography (DOT) and fluorescence molecular tomography (FMT) are two attractive imaging techniques for in vivo physiological and psychological research. They have distinct advantages such as non‐invasiveness, non‐ionizing radiation, high sensitivity and longitudinal monitoring. This paper reviews the key components of DOT and FMT. Light propagation model, mathematical reconstruction algorithm, imaging instrumentation and medical applications are included. Future challenges and perspective on optical tomography are discussed.
Computing a Classic Index for Finite-Horizon Bandits
Authors: Niño-Mora José
Published: September 2010

This paper considers the efficient exact computation of the counterpart of the Gittins index for a finite-horizon discrete-state bandit, which measures for each initial state the average productivity, given by the maximum ratio of expected total discounted reward earned to expected total discounted time expended that can be achieved through a number of successive plays stopping by the given horizon. Besides characterizing optimal policies for the finite-horizon one-armed bandit problem, such an index provides a suboptimal heuristic index rule for the intractable finite-horizon multiarmed bandit problem, which represents the natural extension of the Gittins index rule (optimal in the infinite-horizon case). Although such a finite-horizon index was introduced in classic work in the 1950s, investigation of its efficient exact computation has received scant attention. This paper introduces a recursive adaptive-greedy algorithm using only arithmetic operations that computes the index in (pseudo-)polynomial time in the problem parameters (number of project states and time horizon length). In the special case of a project with limited transitions per state, the complexity is either reduced or depends only on the length of the time horizon. The proposed algorithm is benchmarked in a computational study against the conventional calibration method.
Efficient Optimization of Reliable Two-Node Connected Networks: A Biobjective Approach
Authors: Konak Abdullah , Smith Alice E.
Published: September 2010

This paper presents a biobjective genetic algorithm (GA) to design reliable two-node connected telecommunication networks. Because the exact calculation of the reliability of a network is NP-hard, network designers have been reluctant to use network reliability as a design criterion; however, it is clearly an important aspect. Herein, three methods of reliability assessment are developed: an exact reliability calculation method using factoring, an efficient Monte Carlo estimation procedure using the sequential construction technique and network reductions, and an upper bound for the all-terminal reliability of networks with arbitrary arc reliabilities. These three methods of reliability assessment are used collectively in a biobjective GA with specialized mutation operators that perturb solutions without disturbing two-node connectivity. Computational experiments show that the proposed approach is tractable and significantly improves upon the results found by single-objective heuristics.
Color-Coding Algorithms to the Balanced Path Problem: Computational Issues
Authors: Cappanera Paola , Scutellà Maria Grazia
Published: September 2010

Given a weighted directed network G, we consider the problem of computing k balanced paths from given source nodes to given destination nodes of G, i.e., k paths such that the difference in cost between the longest path and the shortest path is minimized.

Although not yet investigated by the OR scientific community, except for some preliminary theoretical results concerning the special case of acyclic networks, balanced path problems arise in several interesting applications, such as in transportation and in telecommunication settings.

In this work, the focus is on the computation of node-disjoint balanced paths in the general case, where the input graph G could have any structure. Starting from some algorithmic ideas proposed for acyclic networks, a general framework based on the color-coding method for computing simple paths is first described. Then the general framework is specialized, and a pool of algorithms is designed that includes both an exact approach as well as alternative heuristics. The algorithms have been tested on a large suite of instances generated from some benchmark telecommunication instances. An additional set of instances, generated from some benchmark crew scheduling instances, has been used to get an idea of the behavior of the algorithms in the context of transportation applications.

The obtained computational results are very interesting. For the telecommunication instances, in some cases the exact algorithm produced the optimal solution very rapidly; in the remaining cases, some of the proposed heuristics were able to generate high-quality solutions in a very quick time. As for the crew scheduling instances, which are larger and sometimes appear more difficult than the telecommunication ones, a suitable combination of the proposed color-coding issues allowed us to compute the optimal solutions in very short times.