Publications by authors named "Oppenheimer R"

Article Synopsis
  • Brown dwarf companions to stars help us understand planet formation processes, but some of them are more massive than expected based on their luminosities and host star ages.
  • Gliese 229 B, previously thought to be a single entity, was revealed through observations to actually be two brown dwarfs, Gliese 229 Ba and Bb, with masses of 38.1 and 34.4 Jupiter masses, respectively.
  • This discovery challenges existing theories and raises questions about the formation and occurrence of binary brown dwarfs in close orbits around stars.
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Biologically engineered nanomaterials give rise to unique and intriguing properties, which are not available in nature. The full-realization of such has been hindered by the lack of robust and straightforward techniques to produce the required architectures. Here a new bottomup bionano-engineering route is developed to construct nanomaterials using a guided assembly of collagen building blocks, establishing a lithographic process for three-dimensional collagen-based hierarchical micronano-architectures.

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The synthesis of artificial sequence-defined polymers that match and extend the functionality of proteins is an important goal in materials science. One way of achieving this is to program a sequence of chemical reactions between precursor building blocks by means of attached oligonucleotide adapters. However, hydrolysis of the reactive building blocks has so far limited the length and yield of product that can be obtained using DNA-templated reactions.

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Biocatalysis has the potential to enable green chemistry. New methods of enzyme immobilisation will be required to improve enzyme stability, product purification, and compatibility of different enzymes in the same reaction conditions. Deoxyribonucleic acid (DNA) stands out among supramolecular scaffolds, as simple Watson-Crick base-pairing rules can be used to rationally design a unique nanoscale environment around each individual enzyme in a cascade.

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This article presents the experience of a team of students and academics in developing a post-graduate training program in the new field of Synthetic Biology. Our Centre for Doctoral Training in Synthetic Biology (SynBioCDT) is an initiative funded by the United Kingdom's Research Councils of Engineering and Physical Sciences (EPSRC), and Biotechnology and Biological Sciences (BBSRC). SynBioCDT is a collaboration between the Universities of Oxford, Bristol and Warwick, and has been successfully running since 2014, training 78 students in this field.

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Neonicotinoid pesticides can negatively affect bee colonies, but the behavioral mechanisms by which these compounds impair colony growth remain unclear. Here, we investigate imidacloprid's effects on bumblebee worker behavior within the nest, using an automated, robotic platform for continuous, multicolony monitoring of uniquely identified workers. We find that exposure to field-realistic levels of imidacloprid impairs nursing and alters social and spatial dynamics within nests, but that these effects vary substantially with time of day.

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The original version of the Article contained incorrect citation information in reference 67. The reference should read "Russell, A. L.

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Individuals in social insect colonies cooperate to perform collective work. While colonies often respond to changing environmental conditions by flexibly reallocating workers to different tasks, the factors determining which workers switch and why are not well understood. Here, we use an automated tracking system to continuously monitor nest behavior and foraging activity of uniquely identified workers from entire bumble bee (Bombus impatiens) colonies foraging in a natural outdoor environment.

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There is a steady rise in incidence of malignant salivary gland tumors in the United States, with mucoepidermoid carcinoma (MEC) the most frequent. Although 40% of MECs are found in the parotid gland, these lesions possess the capacity to develop anywhere along the aerodigestive tract. Here, we present a case of recurrent tongue MEC in a young adult female patient with history of lung malignancy and multiple brain metastases.

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Background: Sarcopoterium spinosum (S. spinosum) is used by Bedouin medicinal practitioners for the treatment of diabetes. While the anti-diabetic activity of S.

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Natural environments are characterized by variable wind that can pose significant challenges for flying animals and robots. However, our understanding of the flow conditions that animals experience outdoors and how these impact flight performance remains limited. Here, we combine laboratory and field experiments to characterize wind conditions encountered by foraging bumblebees in outdoor environments and test the effects of these conditions on flight.

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Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption.

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Neoplasms metastatic to the oral cavity are rare, accounting for less than 1% of all malignancies found there. When they do occur, they are usually found in the soft tissue or mandible. Metastatic malignancies involving the gingival, alveolar, or buccal mucosa are very rare.

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Pemphigus vegetans is an unusual form of pemphigus vulgaris. Pemphigus of the head and neck region is usually found in areas with mucosa, such as the mouth and pharynx. We present a fascinating case of pemphigus vegetans arising from the nasal dorsum that completely deformed the external nose of a 43-year-old woman.

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Background: Experimental studies suggest that sex hormones may induce or promote the development of hepatocellular carcinoma (HCC). Androgens are converted to estrogens by the CYP19 gene product, aromatase. Hepatic aromatase level and activity have been shown to be markedly elevated in HCC.

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Aim And Objective: This article presents data on attitudes and beliefs about overweight/weight reduction in lesbians. The project was developed to have information on which to base future culturally sensitive interventions to reduce cardiovascular risk in lesbians.

Background: Lesbians have been found to have high rates of obesity/overweight and to be more accepting of it.

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Radiation-induced fibrosis (RIF) is an uncommon complication of radiation therapy. RIF most often occurs in the extremities; it is rare in the head and neck. Only a few medical treatments for RIF are available, and they have been mediocre at best.

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Objective: This study was undertaken to compare patient perceptions of 2 common image-guided breast biopsy procedures on 3 main outcomes: decision making about which procedure to undergo, its convenience, and its side effects.

Methods: Women who had either an excisional or ultrasound-guided core needle breast biopsy in 1997 for a screen-detected lesion had telephone interviews 1 to 3 months after the biopsy. Bivariate associations were tested by using chi(2) and t test statistics.

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Establishing an accurate primary invasive breast cancer size is crucial for patient management. Although ultrasonographic measurement is reported to correlate reliably with the gold standard pathology measurement, few authors have examined the influence of histologic subtype on ultrasound measurement. The common subtypes of invasive breast carcinoma, ductal and lobular, have different growth patterns, which may influence the ability of ultrasound to predict pathologic size.

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In the present study we examined cartilage matrix repair following IL-1-induced matrix depletion. Previous data indicated that, in some cases, chondrocytes can synthesize macromolecules to establish a functional extracellular matrix in response to a matrix-damaging insult or when placed in a three-dimensional environment with inadequate matrix. However, the conditions under which such 'repair' can occur are not entirely clear.

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Objective: This study reports the increase in cancer detection that resulted from independent double interpretation of screening mammography. Although screening mammography is used to detect occult breast cancer, its sensitivity and specificity are limited. Double interpretation of screening mammograms is one proven method used to improve detection, with studies reporting a 5-15% increase in cancer detection.

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Aortobronchial fistula is an extremely rare cause of hemoptysis. Aortobronchial fistula occurs in patients who have a history of thoracic vascular surgery. Because its symptoms are nonspecific, a high index of suspicion is critical if the physician is to detect it.

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