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Bandpass Filtering of DNA Elastic Modes Using Confinement and Tension

During a variety of biological and technological processes, biopolymers are simultaneously subject to both confinement and external forces. Although significant efforts have gone into understanding the physics of polymers that are only confined, or only under tension, little work has been done to explore the effects of the interplay of force and confinement. Here, we study the combined effects of

Cloud and boundary layer interactions over the Arctic sea ice in late summer

Observations from the Arctic Summer Cloud Ocean Study (ASCOS), in the central Arctic sea-ice pack in late summer 2008, provide a detailed view of cloud-atmosphere-surface interactions and vertical mixing processes over the sea-ice environment. Measurements from a suite of ground-based remote sensors, near-surface meteorological and aerosol instruments, and profiles from radiosondes and a helicopte

Exploring alternate states and oligomerization preferences of coiled-coils by de novo structure modeling

Homomeric coiled-coils can self-assemble into a wide range of structural states with different helix topologies and oligomeric states. In this study, we have combined de novo structure modeling with stability calculations to simultaneously predict structure and oligomeric states of homomeric coiled-coils. For dimers an asymmetric modeling protocol was developed. Modeling without symmetry constrain

Manoeuvring the middle ground: Social mobility and the renegotiation of gender and family obligations among Chinese Singaporeans

The article examines Singaporeans' experiences of upward social mobility and how traditional gender roles within the family are renegotiated and reinterpreted in Singapore. When the former British colony gained independence in 1965 its post-colonial government embarked on an ambitious modernization programme, under which villages were demolished and residents relocated to new high-rise estates, fa

Weak antilocalization and electron-electron interaction in coupled multiple-channel transport in a Bi2Se3 thin film.

The electron transport properties of a topological insulator Bi2Se3 thin film are studied in Hall-bar geometry. The film with a thickness of 10 nm is grown by van der Waals epitaxy on fluorophlogopite mica and Hall-bar devices are fabricated from the as-grown film directly on the mica substrate. Weak antilocalization and electron-electron interaction effects are observed and analyzed at low temper

Enacting entrepreneurship research in a pioneering, provocative and participative way: on the work of Bengt Johannisson

Bengt Johannisson received the International Award for Entrepreneurship and Small Business Research in 2008. In this essay we present and evaluate his work over the last four decades in three of its dimensions: pioneering, provocative and participative. While his research interests and themes range widely, early on he resisted the individualization of entrepreneurship studies and instead emphasize

General Conception of Polar Diagrams for the Evaluation of the Potential Machinability of Workpiece Materials

This article presents a polar diagram method developed for describing and evaluating the potential machinability of different workpiece materials. The potential machinability is examined in terms of five critical properties of the workpiece material. Two groups of materials, a group of common steel grades and the other a group of stainless steels, were examined in detail, their polar diagrams illu

The Sensing of Environmental Stimuli by Follicular Dendritic Cells Promotes Immunoglobulin A Generation in the Gut

In the Peyer's patches (PPs), germinal centers (GCs) are chronically induced by bacteria and are the major sites for generation of gut immunoglobulin A (IgA) immune responses. Whether follicular dendritic cells (FDCs) within the GCs directly contribute to the IgA production in PPs is unknown. We showed here that direct stimulation of FDCs by bacterial products and retinoic acid synergistically enh

Incidence of Primary Cancers and Intracranial Tumour Recurrences in Growth Hormone-Treated and Untreated Adult Hypopituitary Patients: Analyses from Hypopituitary Control and Complications Study

Speculation remains that growth hormone (GH) treatment is associated with increased neoplasia risk. Studies in GH-treated childhood cancer survivors suggested higher rates of second neoplasms, while cancer risk data for GH-treated and untreated hypopituitary adults have been variable. We present primary cancer risk data from the Hypopituitary Control and Complications Study (HypoCCS) with a focus

Demography and Democracy: A Global, District-level Analysis of Electoral Contestation

According to the classical perspective, polity size and democracy are inversely related. In this article, we argue that there is an important exception that manifests itself at the district level in settings where multiparty competition is allowed. Specifically, we find that larger districts encourage greater contestation. This results from a little-noticed mechanical effect as well as from severa

Clinical and molecular complexity of breast cancer metastases.

Clinical oncology is advancing toward a more personalized treatment orientation, making the need to understand the biology of metastasis increasingly acute. Dissecting the complex molecular, genetic and clinical phenotypes underlying the processes involved in the development of metastatic disease, which remains the principal cause of cancer-related deaths, could lead to the identification of more

Screening for Retinopathy of Prematurity in Infants Born Before 27 Weeks' Gestation in Sweden

Objective: To analyze screening for retinopathy of prematurity (ROP) during a 3-year period in a national cohort of infants born before 27 weeks' gestation. Methods: A national prospective study of neonatal morbidity in extremely preterm infants was performed in Sweden between April 1, 2004, and March 31, 2007. Screening for ROP was to start in the fifth postnatal week and to continue weekly until

Maternal Obesity and Morbid Obesity: the Risk for Birth Defects in the Offspring

BACKGROUND: The objective of this study was to assess, in a large data set from Swedish Medical Health Registries, whether maternal obesity and maternal morbid obesity were associated with an increased risk for various structural birth defects. METHODS: The study population consisted of 1,049,582 infants born in Sweden from January 1, 1995, through December 31, 2007, with known maternal weight and

Embedding DNA in surfactant mesophases: The phase diagram of the ternary system dodecyltrimethylammonium-DNA/monoolein/water in comparison to the DNA-free analogue.

The self-assembly of a true ternary mixture comprising an electroneutral complex of DNA anions and surfactant cations (dodecyltrimethylammonium cations, DTA), water, and nonionic surfactant (monoolein, MO) has been studied. The phase diagrams of two systems, DTA-DNA/MO/water and, for comparison, dodecyltrimethylammonium bromide (DTAB)/MO/water, were obtained by visual inspection, microscopic exami

Strain mapping in an InGaN/GaN nanowire using a nano-focused x-ray beam

Strained InGaN/GaN core-shell nanowires (NWs) are promising candidates for solid state lighting applications due to their superior properties compared to planar films. NW based devices consist of multiple functional layers, which sum up to many hundred nanometers in thickness, that can uniquely be accessed in a non-destructive fashion by hard X-rays. Here, we present a detailed nanoscale strain ma

p33 (gC1q Receptor) Prevents Cell Damage by Blocking the Cytolytic Activity of Antimicrobial Peptides.

The innate immune system is the first line of defense against invading microbes. Its specificity relies a great deal on host pattern recognition molecules that sense pathogen-associated molecular patterns of the invading pathogen. However, full protection is not always guaranteed, and some early defense mechanisms involved in bacterial killing, such as the complement system, can also exert cytolyt