Proof of the Double Bubble Conjecture in R^n

The least-area hypersurface enclosing and separating two given volumes in R^n is the standard double bubble.Comment: 20 pages, 22 figure

"Infiltrators" or refugees? An analysis of Israel's policy towards African asylum seekers

This article adopts a genealogical approach in examining Israeli immigration policy by focusing on the situation confronting African asylum seekers who have been forced back into Egypt, detained and deported but who have not had their asylum claims properly assessed. Based on immigration policies formulated at the time of Israeli independence, whose principle objective was to secure a Jewish majority state, we argue that Israel’s treatment of African asylum seekers as ‘infiltrators’/economic migrants stems from an insistence on maintaining immigration as a sovereign issue formally isolated from other policy domains. Such an approach is not only in violation of Israel’s commitment to the Refugee Convention, it directly contributes to policies which are ineffective and unduly harsh

Synthetic osteogenic extracellular matrix formed by coated silicon dioxide nanosprings

<p>Abstract</p> <p>Background</p> <p>The design of biomimetic materials that parallel the morphology and biology of extracellular matrixes is key to the ability to grow functional tissues <it>in vitro </it>and to enhance the integration of biomaterial implants into existing tissues <it>in vivo</it>. Special attention has been put into mimicking the nanostructures of the extracellular matrix of bone, as there is a need to find biomaterials that can enhance the bonding between orthopedic devices and this tissue.</p> <p>Methods</p> <p>We have tested the ability of normal human osteoblasts to propagate and differentiate on silicon dioxide nanosprings, which can be easily grown on practically any surface. In addition, we tested different metals and metal alloys as coats for the nanosprings in tissue culture experiments with bone cells.</p> <p>Results</p> <p>Normal human osteoblasts grown on coated nanosprings exhibited an enhanced rate of propagation, differentiation into bone forming cells and mineralization. While osteoblasts did not attach effectively to bare nanowires grown on glass, these cells propagated successfully on nanosprings coated with titanium oxide and gold. We observed a 270 fold increase in the division rate of osteoblasts when grow on titanium/gold coated nanosprings. This effect was shown to be dependent on the nanosprings, as the coating by themselves did not alter the growth rate of osteoblast. We also observed that titanium/zinc/gold coated nanosprings increased the levels of osteoblast production of alkaline phosphatase seven folds. This result indicates that osteoblasts grown on this metal alloy coated nanosprings are differentiating to mature bone making cells. Consistent with this hypothesis, we showed that osteoblasts grown on the same metal alloy coated nanosprings have an enhanced ability to deposit calcium salt.</p> <p>Conclusion</p> <p>We have established that metal/metal alloy coated silicon dioxide nanosprings can be used as a biomimetic material paralleling the morphology and biology of osteogenic extracellular matrix. The coated nanosprings enhance normal human osteoblasts cellular behaviors needed for improving osseointegration of orthopedic materials. Thus, metal-coated nanosprings represent a novel biomaterial that could be exploited for improving success rates of orthopedic implant procedures.</p

A Global Collaboration to Develop and Pilot Test a Mobile Application to Improve Cancer Pain Management in Nepal

INTRODUCTION: Quality palliative care, which prioritizes comfort and symptom control, can reduce global suffering from non-communicable diseases, such as cancer. To address this need, the Nepalese Association of Palliative Care (NAPCare) created pain management guidelines (PMG) to support healthcare providers in assessing and treating serious pain. The NAPCare PMG are grounded in World Health Organization best practices but adapted for the cultural and resource context of Nepal. Wider adoption of the NAPCare PMG has been limited due to distribution of the guidelines as paper booklets. METHODS: Building on a long-standing partnership between clinicians and researchers in the US and Nepal, the NAPCare PMG mobile application (“app”) was collaboratively designed. Healthcare providers in Nepal were recruited to pilot test the app using patient case studies. Then, participants completed a Qualtrics survey to evaluate the app which included the System Usability Scale (SUS) and selected items from the Mobile App Rating Scale (MARS). Descriptive and summary statistics were calculated and compared across institutions and roles. Regression analyses to explore relationships (α = 0.05) between selected demographic variables and SUS and MARS scores were also conducted. RESULTS: Ninety eight healthcare providers (n = 98) pilot tested the NAPCare PMG app. Overall, across institutions and roles, the app received an SUS score of 76.0 (a score > 68 is considered above average) and a MARS score of 4.10 (on a scale of 1 = poor, 5 = excellent). 89.8% (n = 88) “agreed” or “strongly agreed” that the app will help them better manage cancer pain. Age, years of experience, and training in palliative care were significant in predicting SUS scores (p-values, 0.0124, 0.0371, and 0.0189, respectively); institution was significant in predicting MARS scores (p = 0.0030). CONCLUSION: The NAPCare PMG mobile app was well-received, and participants rated it highly on both the SUS and MARS. Regression analyses suggest end-user variables important to consider in designing and evaluating mobile apps in lower resourced settings. Our app design and pilot testing process illustrate the benefits of cross global collaborations to build research capacity and generate knowledge within the local context

The 40Ca(alpha,gamma)44Ti reaction in the energy regime of supernova nucleosynthesis

The 44Ti(t1/2 = 59 y) nuclide, an important signature of supernova nucleosynthesis, has recently been observed as live radioactivity by gamma-ray astronomy from the Cas A remnant. We investigate in the laboratory the major 44Ti production reaction, 40Ca(alpha,gamma)44Ti (E_cm = 0.6-1.2 MeV/u), by direct off- line counting of 44Ti nuclei. The yield, significantly higher than inferred from previous experiments, is analyzed in terms of a statistical model using microscopic nuclear inputs. The associated stellar rate has important astrophysical consequences, increasing the calculated supernova 44Ti yield by a factor ~2 over previous estimates and bringing it closer to Cas A observations.Comment: To be published in Phys. Rev. lett., 4 pages, 1 table, 2 figure

The Soreq Applied Research Accelerator Facility (SARAF) - Overview, Research Programs and Future Plans

The Soreq Applied Research Accelerator Facility (SARAF) is under construction in the Soreq Nuclear Research Center at Yavne, Israel. When completed at the beginning of the next decade, SARAF will be a user facility for basic and applied nuclear physics, based on a 40 MeV, 5 mA CW proton/deuteron superconducting linear accelerator. Phase I of SARAF (SARAF-I, 4 MeV, 2 mA CW protons, 5 MeV 1 mA CW deuterons) is already in operation, generating scientific results in several fields of interest. The main ongoing program at SARAF-I is the production of 30 keV neutrons and measurement of Maxwellian Averaged Cross Sections (MACS), important for the astrophysical s-process. The world leading Maxwellian epithermal neutron yield at SARAF-I ($5\times 10^{10}$ epithermal neutrons/sec), generated by a novel Liquid-Lithium Target (LiLiT), enables improved precision of known MACSs, and new measurements of low-abundance and radioactive isotopes. Research plans for SARAF-II span several disciplines: Precision studies of beyond-Standard-Model effects by trapping light exotic radioisotopes, such as $^6$He, $^8$Li and $^{18,19,23}$Ne, in unprecedented amounts (including meaningful studies already at SARAF-I); extended nuclear astrophysics research with higher energy neutrons, including generation and studies of exotic neutron-rich isotopes relevant to the rapid (r-) process; nuclear structure of exotic isotopes; high energy neutron cross sections for basic nuclear physics and material science research, including neutron induced radiation damage; neutron based imaging and therapy; and novel radiopharmaceuticals development and production. In this paper we present a technical overview of SARAF-I and II, including a description of the accelerator and its irradiation targets; a survey of existing research programs at SARAF-I; and the research potential at the completed facility (SARAF-II).Comment: 32 pages, 31 figures, 10 tables, submitted as an invited review to European Physics Journal

Activism and Legitimation in Israel's Jurisprudence of Occupation

Colonial law need not exclude the colonized in order to subordinate them, and ‘activist’ courts can advance the effect of subordination no less than ‘passive’ courts. As a case study, this article examines the jurisprudential legacy of the Israeli Supreme Court in the context of the prolonged Israeli occupation of Palestine. Applying insights from legal realist, law and society, and critical legal studies scholarship, the article questions the utility of using the activist and passive labels. It illustrates how the Israeli activist court, through multiple legal and discursive moves, has advanced and legitimated the colonization of Palestine; that the court is aware of its role; and that arguments that focus on the court’s informal role do not mitigate this legitimating effect. Unlike other scholars, the article shows that the Israeli court’s role—by extending the power of judicial review to the military’s actions in the occupied areas—is neither novel nor unique or benevolent, as the British colonization of India and the US colonization of Puerto Rico show