bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrating reflexivity into livelihoods research
Authors: Prowse Martin
Published: June 2010

Much development research is not explicit about its methodology or philosophical foundations. Based on the extended case method of Burawoy and the philosophy of critical realism, this article discusses a methodological approach for reflexive livelihoods research that overcomes the unproductive social science dualism of positivism and social constructivism. The approach is linked to a livelihoods framework, and a sequence of research methods that can be iterated in light of research questions.
Benefits of ‘observer effects’: lessons from the field
Authors: Monahan Torin , Fisher Jill A.
Published: June 2010

This article responds to the criticism that ‘observer effects’ in ethnographic research necessarily bias and possibly invalidate research findings. Instead of aspiring to distance and detachment, some of the greatest strengths of ethnographic research lie in cultivating close ties with others and collaboratively shaping discourses and practices in the field. Informants’ performances — however staged for or influenced by the observer — often reveal profound truths about social and/or cultural phenomena. To make this case, first we mobilize methodological insights from the field of science studies to illustrate the contingency and partiality of all knowledge and to challenge the notion that ethnography is less objective than other research methods. Second, we draw upon our ethnographic projects to illustrate the rich data that can be obtained from ‘staged performances’ by informants. Finally, by detailing a few examples of questionable behavior on the part of informants, we challenge the fallacy that the presence of ethnographers will cause informants to self-censor.
The Internet Diabetes Self-Management Workshop for American Indians and Alaska Natives
Authors: Jernigan Valarie Blue Bird , Lorig Kate
Published: June 2010

Type 2 diabetes disproportionately affects American Indians and Alaska Natives (AI/ANs). In the larger population, patient self-management has become an increasing focus of the health care system to help reduce the impact of diabetes. However, little is known about patient self-management programs designed for AI/ANs. This study reports on the feasibility of implementing the Stanford Internet Diabetes Self-Management Workshop within the AI/AN population using a participatory research approach. This is a continuation of self-management studies to assist in meeting the needs of both patients and the health care system for health services that are effective (evidence based), efficient, and culturally appropriate. To our knowledge, this is the first study examining the effectiveness of an Internet-based diabetes patient self-management program among AI/ANs. This article reports on a pilot for a larger randomized study that is ongoing.
Late Concomitant Pseudoaneurysm and Arteriovenous Fistula of the Subclavian Artery: A Developing Country Perspective
Authors: Saulat Hasnain Fatimi  , Deedar-Ali-Khawaja Ranish , Samiullah Khan Niazi  , Luqman Zubair
Published: June 2010

Concomitant subclavian artery pseudoaneurysm and arteriovenous (AV) fistula has been rarely reported. We report a case of late concomitant pseudoaneurysm and AV fistula of the subclavian artery caused by a gunshot wound. Open surgical approach with an infraclavicular approach was used; subclavian artery was repaired with a Gortex interposition graft and subclavian vein was ligated. The postoperative course was uneventful. In developing countries, where the endovascular expertise is unavailable or if the lesion is large, open surgical approach provides similar results as an endovascular approach.
Atacicept: targeting B cells in multiple sclerosis
Authors: Hartung Hans-Peter , Kieseier Bernd C.
Published: June 2010

Multiple sclerosis (MS) has traditionally been considered to be a T-cell-mediated disease. However, there is an increasing body of evidence for the involvement of B cells and autoantibodies in the pathology of this disease, providing a rationale for treatments directed against B cells. In this paper we summarize evidence for the key role of B cells in the immunopathology of MS and review data supporting the use of a novel B-cell targeted therapy, atacicept, in this condition. Atacicept is a human recombinant fusion protein that comprises the binding portion of a receptor for both BLyS (B-Lymphocyte Stimulator) and APRIL (A PRoliferation-Inducing Ligand), two cytokines that have been identified as important regulators of B-cell maturation, function and survival. Atacicept has shown selective effects on cells of the B-cell lineage, acting on mature B cells and blocking plasma cells and late stages of B-cell development while sparing B-cell progenitors and memory cells. The efficacy of atacicept in animal models of autoimmune disease and the biological activity of atacicept in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) has been demonstrated. Clinical studies were initiated to investigate the safety, tolerability and efficacy of atacicept in patients with MS. An unexpected increase in inflammatory activity in one of the trials, however, led to suspension of all atacicept trials in MS.
Hypogonadism, ADAM, and hormone replacement
Authors: Pinsky Michael R. , Hellstrom Wayne J. G.
Published: June 2010

Male hypogonadism, or testosterone deficiency syndrome (TDS), results from a failure of the testes to produce adequate androgen. Patients have low circulating testosterone in combination with clinical symptoms such as fatigue, erectile dysfunction, and body composition changes. The cause may be primary (genetic anomaly, Klinefelter’s syndrome) or secondary (defect in hypothalamus or pituitary), but often presents with the same symptomatology. In the older patient, androgen deficiency of the aging male (ADAM) is an important cause of secondary hypogonadism because testosterone levels decline progressively after age 40. Hypogonadal patients have alterations not only in sexual function and body composition, but also in cognition and metabolism. Regardless of etiology, hypogonadal patients who are both symptomatic and who have clinically significant alterations in laboratory values are candidates for treatment. The goal of hormone replacement therapy in these men is to restore hormone levels to the normal range and to alleviate symptoms suggestive of hormone deficiency. This can be accomplished in a variety of ways, although most commonly testosterone replacement therapy (TRT) is employed.
Lubricin
Authors: Roberts Sally , Menage Janis , Flannery Carl R. , Richardson James B.
Published: June 2010

Objective:

To determine if lubricin was present in the surface layer of repair cartilage formed after autologous chondrocyte implantation (ACI).

Design:

Forty-three biopsies of repair tissue were taken from patients who had been treated with ACI 8 to 68 months previously (mean of 18.0 ± 14.4 months); 30 had flaps of periosteum and 13 of Chondro-Gide®. Cryopreserved sections were stained with hematoxylin and eosin, toluidine blue, and immunostained for lubricin and type II collagen. The quality of repair tissue was scored via OsScore, and clinical improvement in patients was assessed via change in Lysholm score. Normal/control cartilage was studied for comparison ( n = 5).

Results:

Patients’ Lysholm scores improved from 48.1 ± 17 preoperatively to 69.5 ± 21.5 posttreatment. The thickness of repair tissue was 2.9 ± 1.7 mm compared with 2.3 ± 0.6 mm for control cartilage, with an OsScore of 6.7 ± 1.6 (8.9 ± 1.2 for controls). Ninety-eight percent of biopsies had staining for lubricin, with 84% having some in the surface layer (60% of periosteal treated and 100% of Chondro-Gide treated). The improvement in Lysholm score was not significantly different in patients with lubricin present at the surface compared with those without.

Conclusion:

Lubricin was present in almost all samples of repair tissue formed post ACI, often in the surface layer, resembling the distribution that is seen in normal cartilage. The presence of lubricin in the upper layer is likely to have implications for the functioning of the tissue because, via its mucin-like repeats, it appears capable of reducing the friction that could arise in articulating joints.
A review on allogeneic stem cell transplantation for newly diagnosed pediatric acute myeloid leukemia
Authors: Niewerth Denise , Creutzig Ursula , Bierings Marc B. , Kaspers Gertjan J. L.
Published: June 2010

Survival of pediatric acute myeloid leukemia (AML) has improved considerably over the past decades. Since 1985, allogeneic stem cell transplantation (allo-SCT) is widely recommended for patients who have a matched sibling donor. However, it remains controversial whether allo-SCT is superior to chemotherapy for children with newly diagnosed AML. This review summarizes phase 3 clinical trials that compared allo-SCT with chemotherapy (including autologous SCT) in pediatric AML, excluding studies that did not use the intention-to-treat analysis or correct for time-to-transplantation. Although allo-SCT might prevent more relapses than chemotherapy, the number needed for transplantation (with allo-SCT) to prevent one relapse is in the order of 10 patients. Moreover, overall survival is similar with both methods in most recent studies, apparently because of increased salvagability of a relapse when initial therapy concerned chemotherapy only, and because of a higher treatment-related mortality with allo-SCT. Because allo-SCT also gives more severe side effects and results more often in secondary malignancies than chemotherapy, we do not recommend allo-SCT in first remission for pediatric AML in general. Further research should focus on the possibility that subgroups might benefit from allo-SCT, aiming at further improvements in the prognosis of pediatric AML.
A monoclonal antibody against mutated nucleophosmin 1 for the molecular diagnosis of acute myeloid leukemias
Authors: Gruszka Alicja M. , Lavorgna Serena , Consalvo Maria Irno , Ottone Tiziana , Martinelli Chiara , Cinquanta Mario , Ossolengo Giuseppe , Pruneri Giancarlo , Buccisano Francesco , Divona Mariadomenica , Cedrone Michele , Ammatuna Emanuele , Venditti Adriano , de Marco Ario , Lo-Coco Francesco , Pelicci Pier Giuseppe
Published: June 2010

Mutations in the nucleophosmin 1 (NPM1) gene are the most frequent genetic aberrations of acute myeloid leukemia (AML) and define a clinically distinct subset of AML. A monoclonal antibody (T26) was raised against a 19-amino acid polypeptide containing the unique C-terminus of the type A NPM1 mutant protein. T26 recognized 10 of the 21 known NPM1 mutants, including the A, B, and D types, which cover approximately 95% of all cases, and did not cross-react with wild-type NPM1 or unrelated cellular proteins. It performed efficiently with different detection technologies, including immunofluorescence, immunohistochemistry, and flow cytometry. Within a series of consecutive de novo AML patients, 44 of 110 (40%) and 15 of 39 (38%) cases scored positive using the T26 antibody in immunofluorescence and flow cytometry assays, respectively. T26-positive cases were found to be all carrying mutations of NPM1 exclusively, as determined by molecular analysis. T26 is the first antibody that specifically recognizes a leukemia-associated mutant protein. Immunofluorescence or flow cytometry using T26 may thus become a new tool for a rapid, simple, and cost-effective molecular diagnosis of AMLs.
Soluble Fas might serve as a diagnostic tool for gastric adenocarcinoma
Authors: Boroumand-Noughabi Samaneh , Sima Hamid Reza , Ghaffarzadehgan Kamran , Jafarzadeh Mostafa , Raziee Hamid Reza , Hosseinnezhad Hanieh , Moaven Omeed , Rajabi-Mashhadi Mohammad Taghi , Azarian Amir Abbas , Mashhadinejad Mojtaba , Tavakkol-Afshari Jalil
Published: June 2010

Background

Fas (Apo-1/CD95) and its specific ligand (FasL) are key elements in apoptosis. They have been studied in different malignancies but there are few published studies about the soluble forms of these markers (i.e. sFas/sFasL) in gastric cancer. We have compared the serum levels of sFas/sFasL in gastric adenocarcinoma patients and cases with pre-neoplastic lesions as potential markers for early diagnosis, and investigated their relation with clinicopathological characteristics.

Methods

Fifty-nine newly-diagnosed cases of gastric adenocarcinoma who had undergone gastrectomy, along with 62 endoscopically- and histologically-confirmed non-cancer individuals were enrolled in this study. sFas/sFasL serum levels were detected by Enzyme Linked Immunosurbent Assay.

Results

Mean serum sFas level was significantly higher in gastric cancer patients than in control group (305.97 ± 63.71 (pg/ml) vs. 92.98 ± 4.95 (pg/ml), P < 0.001); while the mean serum level of sFasL was lower in patients with gastric adenocarcinoma (0.138 ± 0.04 (pg/ml) vs. 0.150 ± 0.02 (pg/ml), P < 0.001). Mean serum levels of sFas/sFasL were significantly different in both intestinal/diffuse and cardiac/non-cardiac subtypes when compared to the control group (P < 0.001). There was an increase in the serum level of sFas from the first steps of pre-neoplastic lesions to gastric adenocarcinoma (P < 0.001). Patients who had no lymph node involvement (N0) showed significantly higher serum levels of sFas compared to others (P = 0.044).

Conclusions

Production of sFas may play a critical role in the carcinogenesis of intestinal-type gastric cancer. sFas serum level may serve as a non-invasive tool for early diagnosis of gastric cancer.
Effects of a Novel Selective Androgen Receptor Modulator on Dexamethasone-Induced and Hypogonadism-Induced Muscle Atrophy
Authors: Jones Amanda , Hwang Dong-Jin , Narayanan Ramesh , Miller Duane D. , Dalton James T.
Published: June 2010

Glucocorticoids are the most widely used antiinflammatory drugs in the world. However, prolonged use of glucocorticoids results in undesirable side effects such as muscle wasting, osteoporosis, and diabetes. Skeletal muscle wasting, which currently has no approved therapy, is a debilitating condition resulting from either reduced muscle protein synthesis or increased degradation. The imbalance in protein synthesis could occur from increased expression and function of muscle-specific ubiquitin ligases, muscle atrophy F-box (MAFbx)/atrogin-1 and muscle ring finger 1 (MuRF1), or decreased function of the IGF-I and phosphatidylinositol-3 kinase/Akt kinase pathways. We examined the effects of a nonsteroidal tissue selective androgen receptor modulator (SARM) and testosterone on glucocorticoid-induced muscle atrophy and castration-induced muscle atrophy. The SARM and testosterone propionate blocked the dexamethasone-induced dephosphorylation of Akt and other proteins involved in protein synthesis, including Forkhead box O (FoxO). Dexamethasone caused a significant up-regulation in the expression of ubiquitin ligases, but testosterone propionate and SARM administration blocked this effect by phosphorylating FoxO. Castration induced rapid myopathy of the levator ani muscle, accompanied by up-regulation of MAFbx and MuRF1 and down-regulation of IGF-I, all of which was attenuated by a SARM. The results suggest that levator ani atrophy caused by hypogonadism may be the result of loss of IGF-I stimulation, whereas that caused by glucocorticoid treatment relies almost solely on up-regulation of MAFbx and MuRF1. Our studies provide the first evidence that glucocorticoid- and hypogonadism-induced muscle atrophy are mediated by distinct but overlapping mechanisms and that SARMs may provide a more effective and selective pharmacological approach to prevent glucocorticoid-induced muscle loss than steroidal androgen therapy.
Axonal projections of mechanoreceptive dorsal root ganglion neurons depend on Ret
Authors: Honma Yutaka , Kawano Masako , Kohsaka Shinichi , Ogawa Masaharu
Published: June 2010

Establishment of connectivity between peripheral and central organs is essential for sensory processing by dorsal root ganglion (DRG) neurons. Using Ret as a marker for mechanoreceptive DRG neurons, we show that both central and peripheral projections of mechanoreceptive neurons are severely impaired in the absence of Ret. Death of DRG neurons in Ret-deficient mice can be rescued by eliminating Bax, although their projections remain disrupted. Furthermore, ectopic expression of the Ret ligand neurturin, but not Gdnf, in the spinal cord induces aberrant projection of mechanoreceptive afferents. Our results demonstrate that Ret expression in DRG neurons is crucial for the neurturin-mediated formation of precise axonal projections in the central nervous system.
Myocardin-related transcription factors regulate the Cdk5/Pctaire1 kinase cascade to control neurite outgrowth, neuronal migration and brain development
Authors: Mokalled Mayssa H. , Johnson Aaron , Kim Yuri , Oh Jiyeon , Olson Eric N.
Published: June 2010

Numerous motile cell functions depend on signaling from the cytoskeleton to the nucleus. Myocardin-related transcription factors (MRTFs) translocate to the nucleus in response to actin polymerization and cooperate with serum response factor (Srf) to regulate the expression of genes encoding actin and other components of the cytoskeleton. Here, we show that MRTF-A (Mkl1) and MRTF-B (Mkl2) redundantly control neuronal migration and neurite outgrowth during mouse brain development. Conditional deletion of the genes encoding these Srf coactivators disrupts the formation of multiple brain structures, reflecting a failure in neuronal actin polymerization and cytoskeletal assembly. These abnormalities were accompanied by dysregulation of the actin-severing protein gelsolin and Pctaire1 (Cdk16) kinase, which cooperates with Cdk5 to initiate a kinase cascade that governs cytoskeletal rearrangements essential for neuron migration and neurite outgrowth. Thus, the MRTF/Srf partnership interlinks two key signaling pathways that control actin treadmilling and neuronal maturation, thereby fulfilling a regulatory loop that couples cytoskeletal dynamics to nuclear gene transcription during brain development.
The RGM protein DRAG-1 positively regulates a BMP-like signaling pathway inCaenorhabditis elegans
Authors: Tian Chenxi , Sen Debjeet , Shi Herong , Foehr Marisa L. , Plavskin Yevgeniy , Vatamaniuk Olena K. , Liu Jun
Published: June 2010

The bone morphogenetic protein (BMP) signaling pathway regulates multiple developmental and homeostatic processes. Mutations in the pathway can cause a variety of somatic and hereditary disorders in humans. Multiple levels of regulation, including extracellular regulation, ensure proper spatiotemporal control of BMP signaling in the right cellular context. We have identified a modulator of the BMP-like Sma/Mab pathway in C. elegans called DRAG-1. DRAG-1 is the sole member of the repulsive guidance molecule (RGM) family of proteins in C. elegans, and is crucial in regulating body size and mesoderm development. Using a combination of molecular genetic and biochemical analyses, we demonstrate that DRAG-1 is a membrane-associated protein that functions at the ligand-receptor level to modulate the Sma/Mab pathway in a cell-type-specific manner. We further show that DRAG-1 positively modulates this BMP-like pathway by using a novel Sma/Mab-responsive reporter. Our work provides a direct link between RGM proteins and BMP signaling in vivo and a simple and genetically tractable system for mechanistic studies of RGM protein regulation of BMP pathways.
Synthesis and Hybridization Properties of Oligonucleotides Incorporating Bi- and Tricyclic Cytosine Derivatives
Authors: Ohkubo Akihiro , Sakaue Toshiyuki , Tsunoda Hirosuke , Seio Kohji , Sekine Mitsuo
Published: June 2010

DNA oligomers with cytosine bases (Cpyr, Ctpp, and Cpnx) with bi- and tricyclic ring structures were synthesized. Among the modified bases, Cpyr was found to enhance the duplex stability retaining the base recognition ability. Ctpp was effective in neither hybridization nor base recognition. Cpnx could form more strongly a matched base pair with guanine but lost more significantly base recognition than Cpyr.
1-Methylimidazolium Chlorosulfate ([HMIm]SO3Cl): A Novel Ionic Liquid with Dual Brønsted–Lewis Acidity
Authors: Bao Quanxi , Qiao Kun , Tomida Daisuke , Yokoyama Chiaki
Published: June 2010

A novel acidic ionic liquid, 1-methylimidazolium chlorosulfate ([HMIm]SO3Cl), with dual Brønsted–Lewis acidity was synthesized. This compound provided better catalytic performance in esterification and dehydration of fructose to 5-hydroxymethylfurfural (HMF) than acidic ionic liquids with only Brønsted or Lewis acidity.
An Intuitive Introduction to Hypothesis Testing
Authors: Dambolena Ismael G. , Eriksen Steven E. , Kopcso David P.
Published: June 2010

The traditional approach to teaching hypothesis testing, based on test statistics, is often perceived as lengthy and convoluted. This perception is of particular concern in business schools where the main focus of statistics education should be on providing practical decision-making tools to future managers. This paper discusses the results of a two-year experiment incorporating a more intuitive graph-based introduction to hypothesis testing that places the concept of p-value in a central role. Using this innovative approach at our institution we decreased class coverage time and improved students' understanding and retention with excellent results.
Teaching Health-Care Operations in the MBA Program at Vanderbilt University Owen Graduate School of Management
Authors: Lapré Michael A.
Published: June 2010

This paper describes a case-based MBA elective “Health Care Operations” (HCO) developed by an instructor without prior education, consulting, or research experience in the health-care field. HCO helps MBA students analyze health-care organizations using both qualitative and quantitative principles of operations management. The course outline covers (1) designing health-care delivery systems, (2) capacity planning and decision making under uncertainty, and (3) process failure, learning, and improvement. The paper identifies challenges faced in the design and delivery of the course as well as lessons learned. I hope that this paper will be useful for other instructors who want to teach health-care operations.
Decision Rings: Making Decision Trees Visual and non-Mathematical
Authors: Bordley Robert F.
Published: June 2010

The decision tree is widely used to represent and solve decision problems. Because it involves the explicit use of mathematics, it tends to be used for technical audiences. This paper presents an alternative way of representing and solving the decision tree for nontechnical audiences.

A common step in quantifying a decision tree is to ask subjects to quantify their beliefs about an event using a probability wheel. This procedure implies that subjects do have geometrical intuitions about uncertainties. Our new approach to decision analysis builds on this insight.

Instead of representing the tree with lines, we represent the various levels of a decision tree as concentric rings. Specific events are represented as segments in those rings with the size of the segment being proportional to the probability of the event occurring. Payoffs are represented by coloring various segments. The standard expected value calculation of decision analysis corresponds to mixing the colors from outer segments to color inner segments.

This new way of representing and solving a decision tree is completely visual and eliminates the need for any mathematics.
OR/MS Games: 1. A Neglected Educational Resource
Authors: Sniedovich Moshe
Published: June 2010

Games offer OR/MS lecturers and students important educational resources. However, for various reasons the OR/MS literature in general—and introductory textbooks in particular—scarcely make use of this treasure. In this discussion we suggest that it is time to reconsider this position and regard games as a valuable source for developing educationally rich material for OR/MS courses. Hopefully this will initiate a constructive discussion on this topic that will eventually facilitate the identification and development of good OR/MS educational resources and stimulate the development of new exciting ways to make OR/MS tools more accessible to students and the public at large.
Optimal Choice and Beliefs with Ex Ante Savoring and Ex Post Disappointment
Authors: Gollier Christian , Muermann Alexander
Published: June 2010

We propose a new decision criterion under risk in which individuals extract both utility from anticipatory feelings ex ante and disutility from disappointment ex post. The decision maker chooses his degree of optimism, given that more optimism raises both the utility of ex ante feelings and the risk of disappointment ex post. We characterize the optimal beliefs and the preferences under risk generated by this mental process and apply this criterion to a simple portfolio choice/insurance problem. We show that these preferences are compatible with first-degree and second-degree stochastic dominance and yield a preference for early resolution of uncertainty. Furthermore, they are consistent with observed violations of the independence axiom, such as the preference reversal in the Allais paradox, and predict that the decision maker takes on less risk compared to an expected utility maximizer. Our decision criterion can thus help explain the equity premium puzzle and the preference for low deductibles in insurance contracts.
Test expectancy affects metacomprehension accuracy
Authors: Thiede Keith W. , Wiley Jennifer , Griffin Thomas D.
Published: June 2010

Background. Theory suggests that the accuracy of metacognitive monitoring is affected by the cues used to judge learning. Researchers have improved monitoring accuracy by directing attention to more appropriate cues; however, this is the first study to more directly point students to more appropriate cues using instructions regarding tests and practice tests.

Aims. The purpose of the present study was to examine whether the accuracy metacognitive monitoring was affected by the nature of the test expected.

Sample and method. Students (N= 59) were randomly assigned to one of two test expectancy groups (memory vs. inference). Then after reading texts, judging learning, completed both memory and inference tests.

Results. Test performance and monitoring accuracy were superior when students received the kind of test they had been led to expect rather than the unexpected test.

Conclusion. Tests influence students' perceptions of what constitutes learning. Our findings suggest that this could affect how students prepare for tests and how they monitoring their own learning.
Ricci flow, entropy and optimal transportation
Authors: McCann Robert J. , Topping Peter M.
Published: June 2010

Let a smooth family of Riemannian metrics $g(\tau)$ satisfy the backwards Ricci flow equation on a compact oriented $n$-dimensional manifold $M$. Suppose two families of normalized $n$-forms $\omega(\tau) \ge 0$ and $\tilde \omega(\tau) \ge 0$ satisfy the forwards (in $\tau$) heat equation on $M$ generated by the connection Laplacian $\Delta_{g(\tau)}$. If these $n$-forms represent two evolving distributions of particles over $M$, the minimum root-mean-square distance $W_2(\omega(\tau),\tilde \omega(\tau),\tau)$ to transport the particles of $\omega(\tau)$ onto those of $\tilde \omega(\tau)$ is shown to be non-increasing as a function of $\tau$, without sign conditions on the curvature of $(M,g(\tau))$. Moreover, this contractivity property is shown to characterize supersolutions to the Ricci flow.
Nonhomeomorphic conjugates of connected Shimura varieties
Authors: Milne James S. , Suh Junecue
Published: June 2010

We show that conjugation by an automorphism of ${\Bbb C}$ may change the topological fundamental group of a locally symmetric variety over ${\Bbb C}$. As a consequence, we obtain a large class of algebraic varieties defined over number fields with the property that different embeddings of the number field into ${\Bbb C}$ give complex varieties with nonisomorphic fundamental groups.
Hessian and gradient estimates for three dimensional special Lagrangian equations with large phase
Authors: Warren Micah , Yuan Yu
Published: June 2010

We obtain a priori interior Hessian and gradient estimates for special Lagrangian equations with phase larger than a critical value in dimension three. Gradient estimates are also derived for critical and super critical phases in general dimensions.
Null structure and almost optimal local well-posedness of the Maxwell-Dirac system
Authors: D'Ancona Piero , Foschi Damiano , Selberg Sigmund
Published: June 2010

We uncover the full null structure of the Maxwell-Dirac system in Lorenz gauge. This structure, which cannot be seen in the individual component equations, but only when considering the system as a whole, is expressed in terms of tri- and quadrilinear integral forms with cancellations measured by the angles between spatial frequencies. In the 3D case, we prove frequency-localized $L^2$ space-time estimates for these integral forms at the scale invariant regularity up to a logarithmic loss, hence we obtain almost optimal local well-posedness of the system by iteration.
Non-simple purely infinite rings
Authors: Pino G. Aranda , Goodearl K. R. , Perera F. , Molina M. Siles
Published: June 2010

In this paper we introduce the concept of purely infinite rings, which in the simple case agrees with the already existing notion of pure infiniteness. We establish various permanence properties of this notion, with respect to passage to matrix rings, corners, and behaviour under extensions, so being purely infinite is preserved under Morita equivalence. We show that a wealth of examples falls into this class, including important analogues of constructions commonly found in operator algebras. In particular, for any (s-) unital $K$-algebra having enough nonzero idempotents (for example, for a von Neumann regular algebra) its tensor product over $K$ with many non-simple Leavitt path algebras is purely infinite.
On a class of II 1 factors with at most one Cartan subalgebra, II
Authors: Ozawa Narutaka , Popa Sorin
Published: June 2010

This is a continuation of our previous paper studying the structure of Cartan subalgebras of von Neumann factors of type ${\rm II}_1$. We provide more examples of ${\rm II}_1$ factors having either zero, one, or several Cartan subalgebras. We also prove a rigidity result for some group measure space ${\rm II}_1$ factors.
Noncommutative Riesz transforms — a probabilistic approach
Authors: Junge M. , Mei T.
Published: June 2010

For $2\le p < \infty$ we show the lower estimates $$ \|A^{\frac 12}x\|_p \le c(p)\max\{\|\Gamma(x,x)^{\frac{1}{2}}\|_p, \|\Gamma(x^*,x^*)^{\frac{1}{2}}\|_p\} $$ for the Riesz transform associated to a semigroup $(T_t)$ of completely positive maps on a von Neumann algebra with negative generator $T_t=e^{-tA}$, and gradient form $$ 2\Gamma(x,y) = Ax^*y+x^*Ay-A(x^*y).$$ Among other hypotheses we assume that $\Gamma^2\ge 0$ and the existence of a Markov dilation for $(T_t)$. As an application we provide new examples of quantum metric spaces for discrete groups with rapid decay. In this context a compactness condition follows from Sobolev embedding results based on a notion of dimension due to Varopoulos.
Variational constructions for some satellite orbits in periodic gravitational force fields
Authors: Chen Kuo-Chang
Published: June 2010

In a gravitational force field, a bounded orbit of an infinitesimal point mass is called a satellite orbit. The purpose of this paper is to establish a variational theory for the existence of some relative periodic satellite orbits in periodic gravitational force fields. The gravitation field can be generated by a relative equilibrium or a uniformly rotating asteroid. Our approach is to regard the aggregate of primaries together with the small satellite as a restricted full two-body problem, and then look for direct and retrograde relative periodic satellite orbits by direct methods of calculus of variations. Regularity of the action-minimizing satellite orbit is obtained by providing satisfactory lower bound estimates for the distance between the satellite and the mass center. An upper bound estimate for this distance is also provided as a contrast to classical existence proofs by continuation from infinity.
On a New Schedule: Transitions to Adulthood and Family Change
Authors: Furstenberg Frank F.
Published: June 2010

Frank Furstenberg examines how the newly extended timetable for entering adulthood is affecting, and being affected by, the institution of the Western, particularly the American, family. He reviews a growing body of research on the family life of young adults and their parents and draws out important policy implications of the new schedule for the passage to adulthood. Today, says Furstenberg, home-leaving, marriage, and the onset of childbearing take place much later in the life span than they did during the period after World War II. After the disappearance of America's well-paying unskilled and semi-skilled manufacturing jobs during the 1960s, youth from all economic strata began remaining in school longer and marrying and starting their own families later. Increasing numbers of lower-income women did not marry at all but chose, instead, non-marital parenthood—often turning to their natal families for economic and social support, rather than to their partners. As the period of young adults' dependence on their families grew longer, the financial and emotional burden of parenthood grew heavier. Today, regardless of their income level, U.S. parents provide roughly the same proportion of their earnings to support their young adult children. Unlike many nations in Europe, the United States, with its relatively underdeveloped welfare system, does not invest heavily in education, health care, and job benefits for young adults. It relies, instead, on families' investments in their own adult children. But as the transition to adulthood becomes more protracted, the increasing family burden may prove costly to society as a whole. Young adults themselves may begin to regard childbearing as more onerous and less rewarding. The need to provide greater support for children for longer periods may discourage couples from having additional children or having children at all. Such decisions could lead to lower total fertility, ultimately reduce the workforce, and further aggravate the problem of providing both for increasing numbers of the elderly and for the young. U.S. policy makers must realize the importance of reinforcing the family nest and helping reduce the large and competing demands that are being placed on today's parents.
Programs and Policies to Assist High School Dropouts in the Transition to Adulthood
Authors: Bloom Dan
Published: June 2010

Dan Bloom of MDRC examines policies and programs designed to help high school dropouts improve their educational attainment and labor market outcomes. So called "second-chance" programs, he says, have long provided some combination of education, training, employment, counseling, and social services. But the research record on their effectiveness is fairly thin, he says, and the results are mixed. Bloom describes eleven employment- or education-focused programs serving high school dropouts that have been rigorously evaluated over the past thirty years. Some relied heavily on paid work experience, while others focused more on job training or education. Some programs, especially those that offered paid work opportunities, generated significant increases in employment or earnings in the short term, but none of the studies that followed participants for more than a couple of years found lasting improvements in economic outcomes. Nevertheless, the findings provide an important foundation on which to build. Because of the high individual and social costs of ignoring high school dropouts, the argument for investing more public funds in services, systems, and research for these young people is strong. The paucity of conclusive evidence, however, makes it hard to know how to direct resources and magnifies the importance of ensuring that all new initiatives provide for rigorous evaluation of their impacts. Bloom concludes with recommendations for policy and research aimed at building on current efforts to expand and improve effective programs for dropouts while simultaneously developing and testing new approaches that might be more effective and strengthening local systems to support vulnerable young people. He stresses the importance of identifying and disseminating strategies to engage young people who are more seriously disconnected and unlikely to join programs. A recurring theme is that providing young people with opportunities for paid work may be useful both as an engagement tool and as a strategy for improving long-term labor market outcomes.
Young Adults and Higher Education: Barriers and Breakthroughs to Success
Authors: Brock Thomas
Published: June 2010

Although access to higher education has increased substantially over the past forty years, student success in college—as measured by persistence and degree attainment—has not improved at all. Thomas Brock reviews systematic research findings on the effectiveness of various interventions designed to help at-risk students remain in college. Brock shows how changes in federal policy and public attitudes since the mid-1960s have opened up higher education to women, minorities, and nontraditional students and also shifted the "center of gravity" in higher education away from traditional four-year colleges toward nonselective community colleges. Students at two-year colleges, however, are far less likely than those at four-year institutions to complete a degree. Brock argues that the nation's higher education system must do much more to promote student success. Three areas, he says, are particularly ripe for reform: remedial education, student support services, and financial aid. In each of these three areas, Brock reviews programs and interventions that community colleges have undertaken in order to raise completion rates. Some colleges have, for example, experimented with remedial programs that build social cohesion between students and faculty and integrate content across courses. Other colleges have tested student support service programs that offer counseling and advising that are regular, intensive, and personalized. Still others have experimented with ways to simplify the financial aid application process and incentivize students to earn good grades and persist in school. Research shows that such programs and interventions can improve student outcomes, but Brock argues that more must be done to bring proven practices to scale and to test new ideas that might lead to better results. Institutions that most need help are those that provide the greatest access to nontraditional and underprepared students in community colleges and less selective universities.
Labor Market Outcomes and the Transition to Adulthood
Authors: Danziger Sheldon , Ratner David
Published: June 2010

According to Sheldon Danziger and David Ratner, changes in the labor market over the past thirty-five years, such as labor-saving technological changes, increased globalization, declining unionization, and the failure of the minimum wage to keep up with inflation, have made it more difficult for young adults to attain the economic stability and self-sufficiency that are important markers of the transition to adulthood. Young men with no more than a high school degree have difficulty earning enough to support a family. Even though young women have achieved gains in earnings, employment, and schooling relative to men in recent decades, those without a college degree also struggle to achieve economic stability and self-sufficiency. The authors begin by describing trends in labor market outcomes for young adults—median annual earnings, the extent of low-wage work, employment rates, job instability, and the returns to education. Then they examine how these outcomes may contribute to delays in other markers of the transition to adulthood—completing an education, establishing independent living arrangements, and marrying and having children. They conclude that adverse changes in labor market outcomes are related to those delays but have not been shown to be the primary cause. Danziger and Ratner next consider several public policy reforms that might improve the economic outlook for young adults. They recommend policies that would increase the returns to work, especially for less-educated workers. They propose raising the federal minimum wage and adjusting it annually to maintain its value relative to the median wage. Expanding the Earned Income Tax Credit for childless low-wage workers, the authors say, could also raise the take-home pay of many young adult workers, with minimal adverse employment effects. New policies should also provide work opportunities for young adults who cannot find steady employment either because of poor economic conditions or because of physical and mental disabilities or criminal records that make it hard for them to work steadily even when the economy is strong. Finally, the authors recommend increasing federal Pell grants for college and improving access to credit for would-be college students to raise the educational attainment of young adults from low-income families.
Civic Engagement and the Transition to Adulthood
Authors: Flanagan Constance , Levine Peter
Published: June 2010

Constance Flanagan and Peter Levine survey research on civic engagement among U.S. adolescents and young adults. Civic engagement, they say, is important both for the functioning of democracies and for the growth and maturation it encourages in young adults, but opportunities for civic engagement are not evenly distributed by social class or race and ethnicity. Today's young adults, note the authors, are less likely than those in earlier generations to exhibit many important characteristics of citizenship, raising the question of whether these differences represent a decline or simply a delay in traditional adult patterns of civic engagement. Flanagan and Levine also briefly discuss the civic and political lives of immigrant youth in the United States, noting that because these youth make up a significant share of the current generation of young adults, their civic engagement is an important barometer of the future of democracy. The authors next survey differences in civic participation for youth from different social, racial, and ethnic backgrounds. They explore two sets of factors that contribute to a lower rate of civic engagement among low-income and minority young adults. The first is cumulative disadvantage—unequal opportunities and influences before adulthood, especially parental education. The second is different institutional opportunities for civic engagement among college and non-college youth during the young-adult years. Flanagan and Levine survey various settings where young adults spend time—schools and colleges, community organizations, faith-based institutions, community organizing and activism projects, and military and other voluntary service programs—and examine the opportunities for civic engagement that each affords. As the transition to adulthood has lengthened, say the authors, colleges have become perhaps the central institution for civic incorporation of younger generations. But no comparable institution exists for young adults who do not attend college. Opportunities for sustained civic engagement by year-long programs such as City Year could provide an alternative opportunity for civic engagement for young adults from disadvantaged families, allowing them to stay connected to mainstream opportunities and to adults who could mentor and guide their way.
What's Going on with Young People Today? The Long and Twisting Path to Adulthood
Authors: Settersten Richard A. , Ray Barbara
Published: June 2010

Richard Settersten and Barbara Ray examine the lengthening transition to adulthood over the past several decades, as well as the challenges the new schedule poses for young people, families, and society. The authors begin with a brief history of becoming an adult, noting that the schedule that youth follow to arrive at adulthood changes to meet the social realities of each era. For youth to leave home at an early age during the 1950s, for example, was "normal" because opportunities for work were plentiful and social expectations of the time reinforced the need to do so. But the prosperity that made it possible for young adults of that era to move quickly into adult roles did not last. The economic and employment uncertainties that arose during the 1970s complicated enormously the decisions that young adults had to make about living arrangements, educational investments, and family formation. The authors next take a closer look at changes in the core timing shifts in the new transition—the lengthening time it now takes youth to leave home, complete school, enter the workforce, marry, and have children. They stress that today's new schedule for attaining independence leaves many families overburdened as they support their children for an extended period. The continued need to rely on families for financial assistance, the authors say, exacerbates the plight of young people from a variety of vulnerable backgrounds. It also raises complex questions about who is responsible for the welfare of young people and whether the risks and costs newly associated with the early adult years should be absorbed by markets, by families, or by governments. Settersten and Ray stress that the longer transition to adulthood strains not only families but also the institutions that have traditionally supported young Americans in making that transition—such as residential colleges and universities, community colleges, military service, and national service programs. They emphasize the need to strengthen existing social institutions and create new ones to reflect more accurately the realities of a longer and more complex passage into adult life.
The Military and the Transition to Adulthood
Authors: Kelty Ryan , Kleykamp Meredith , Segal David R.
Published: June 2010

Ryan Kelty, Meredith Kleykamp, and David Segal examine the effect of military service on the transition to adulthood. They highlight changes since World War II in the role of the military in the lives of young adults, focusing especially on how the move from a conscription to an all-volunteer military has changed the way military service affects youths' approach to adult responsibilities. The authors note that today's all-volunteer military is both career-oriented and family-oriented, and they show how the material and social support the military provides to young servicemen and women promotes responsible membership in family relationships and the wider community. As a result, they argue, the transition to adulthood, including economic independence from parents, is more stable and orderly for military personnel than for their civilian peers. At the same time, they stress that serving in the military in a time of war holds dangers for young adults. The authors examine four broad areas of military service, focusing in each on how men and women in uniform today make the transition to adulthood. They begin by looking at the social characteristics of those who serve, especially at differences in access to the military and its benefits by socio-demographic characteristics, such as age, gender, race and ethnicity, social class, and sexual orientation. Military service also has important effects on family formation, including the timing of marriage and parenthood, family structure, and the influence of military culture on families. Family formation among servicemen and women, the authors observe, is earlier and more stable than among civilians of the same age. The authors then consider the educational and employment consequences of service. Finally, they scrutinize the dangers of military service during times of war and examine the physical and psychological effects of wartime military service. They also note the sexual trauma endured both by male and female military personnel and the physical and symbolic violence women can experience in a male-dominated institution. Kelty, Kleykamp, and Segal conclude by seeking policy lessons from the military's success in facilitating the transition to adulthood for young men and women in uniform.