1,387 research outputs found
Order out of Randomness : Self-Organization Processes in Astrophysics
Self-organization is a property of dissipative nonlinear processes that are
governed by an internal driver and a positive feedback mechanism, which creates
regular geometric and/or temporal patterns and decreases the entropy, in
contrast to random processes. Here we investigate for the first time a
comprehensive number of 16 self-organization processes that operate in
planetary physics, solar physics, stellar physics, galactic physics, and
cosmology. Self-organizing systems create spontaneous {\sl order out of chaos},
during the evolution from an initially disordered system to an ordered
stationary system, via quasi-periodic limit-cycle dynamics, harmonic mechanical
resonances, or gyromagnetic resonances. The internal driver can be gravity,
rotation, thermal pressure, or acceleration of nonthermal particles, while the
positive feedback mechanism is often an instability, such as the
magneto-rotational instability, the Rayleigh-B\'enard convection instability,
turbulence, vortex attraction, magnetic reconnection, plasma condensation, or
loss-cone instability. Physical models of astrophysical self-organization
processes involve hydrodynamic, MHD, and N-body formulations of Lotka-Volterra
equation systems.Comment: 61 pages, 38 Figure
Using Low-Dose Radiation to Potentiate the Effect of Induction Chemotherapy in Head and Neck Cancer: Results of a Prospective Phase 2 Trial
Purpose: Low-dose fractionated radiation therapy (LDFRT) induces effective cell killing through hyperradiation sensitivity and potentiates effects of chemotherapy. We report our second investigation of LDFRT as a potentiator of the chemotherapeutic effect of induction carboplatin and paclitaxel in locally advanced squamous cell cancer of the head and neck (SCCHN).
Experimental Design: Two cycles of induction therapy were given every 21 days: paclitaxel (75 mg/m2) on days 1, 8, and 15; carboplatin (area under the curve 6) day 1; and LDFRT 50 cGy fractions (2 each on days 1, 2, 8, and 15). Objectives included primary site complete response rate; secondary included overall survival, progression-free survival (PFS), disease-specific survival, and toxicity.
Results: A total of 24 evaluable patients were enrolled. Primary sites included oropharynx (62.5%), larynx (20.8%), oral cavity (8.3%), and hypopharynx (8.3%). Grade 3/4 toxicities included neutropenia (20%), leukopenia (32%), dehydration/hypotension (8%), anemia (4%), infection (4%), pulmonary/allergic rhinitis (4%), and diarrhea (4%). Primary site response rate was 23/24 (95.8%): 15/24 (62.5%) complete response, 8/24 (33.3%) partial response, and 1/24 (4.2%) stable disease. With median follow-up of 7.75 years, 9-year rates for overall survival were 49.4% (95% confidence interval [CI], 30.5-79.9), PFS was 72.2% (CI, 55.3-94.3), and disease-specific survival was 65.4% (44.3-96.4).
Conclusion: Chemopotentiating LDFRT combined with paclitaxel and carboplatin is effective in SCCHN and provided an excellent median overall survival of 107.2 months, with median PFS not yet reached in this locally advanced SCCHN cohort. This compares favorably to prior investigations and caused fewer grade 3 and 4 toxicities than more intensive, 3-drug induction regimens. This trial demonstrates the innovative use of LDFRT as a potentiator of chemotherapy
Ursinus College Alumni Journal, March 1962
President\u27s page • Pennsylvania Female College • College souvenirs: Class of 1862 • Inside India • James E. Wagner elected Vice-President of Ursinus • New power plant begun • New offices • Bequests committee formed • Has America neglected her creative minority? • Announcing the second annual Alumni Seminar • Jessie Royer Greaves, \u2792, recipient of first alumni award • Nominees for Alumni Association offices • Mid-year report of 1962 Loyalty Fund campaign • From grey flannel to Alaskan seal • Ursinus homecoming in Alaska • Wrestling • Girls\u27 basketball • Basketball • Ursinus ambassadors abroad • Class notes • Weddings • Births • Necrology • Ursinus Women\u27s Club • Regionals • Alumni Dayhttps://digitalcommons.ursinus.edu/alumnijournal/1074/thumbnail.jp
Extracellular Targets to Reduce Excessive Scarring in Response to Tissue Injury
Excessive scar formation is a hallmark of localized and systemic fibrotic disorders. Despite extensive studies to define valid anti-fibrotic targets and develop effective therapeutics, progressive fibrosis remains a significant medical problem. Regardless of the injury type or location of wounded tissue, excessive production and accumulation of collagen-rich extracellular matrix is the common denominator of all fibrotic disorders. A long-standing dogma was that anti-fibrotic approaches should focus on overall intracellular processes that drive fibrotic scarring. Because of the poor outcomes of these approaches, scientific efforts now focus on regulating the extracellular components of fibrotic tissues. Crucial extracellular players include cellular receptors of matrix components, macromolecules that form the matrix architecture, auxiliary proteins that facilitate the formation of stiff scar tissue, matricellular proteins, and extracellular vesicles that modulate matrix homeostasis. This review summarizes studies targeting the extracellular aspects of fibrotic tissue synthesis, presents the rationale for these studies, and discusses the progress and limitations of current extracellular approaches to limit fibrotic healing
Beautiful Mirrors at the LHC
We explore the "Beautiful Mirrors" model, which aims to explain the measured
value of , discrepant at the level. This scenario
introduces vector-like quarks which mix with the bottom, subtly affecting its
coupling to the . The spectrum of the new particles consists of two
bottom-like quarks and a charge -4/3 quark, all of which have electroweak
interactions with the third generation. We explore the phenomenology and
discovery reach for these new particles at the LHC, exploring single mirror
quark production modes whose rates are proportional to the same mixing
parameters which resolve the anomaly. We find that for mirror quark
masses is required to
reasonably establish the scenario and extract the relevant mixing parameters.Comment: version to be published in JHE
Sea Level Rise and the Dynamics of the Marsh-Upland Boundary
During sea level rise, salt marshes transgress inland invading low-lying forests, agricultural fields, and suburban areas. This transgression is a complex process regulated by infrequent storms that flood upland ecosystems increasing soil salinity. As a result upland vegetation is replaced by halophyte marsh plants. Here we present a review of the main processes and feedbacks regulating the transition from upland ecosystems to salt marshes. The goal is to provide a process-based framework that enables the development of quantitative models for the dynamics of the marsh-upland boundary. Particular emphasis is given to the concept of ecological ratchet, combining the press disturbance of sea level rise with the pulse disturbance of storms
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The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer.
Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM -/- patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors
Development of a Direct Fabrication Technique for Full-Shell X-Ray Optics
No abstract availabl
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