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Variational formulas and disorder regimes of random walks in random potentials
No full textWe give two variational formulas (qVar1) and (qVar2) for the quenched free energy of a random walk in random potential (RWRP) when (i) the underlying walk is directed or undirected, (ii) the environment is stationary and ergodic, and (iii) the potential is allowed to depend on the next step of the walk which covers random walk in random environment (RWRE). In the directed i.i.d. case, we also give two variational formulas (aVar1) and (aVar2) for the annealed free energy of RWRP. These four formulas are the same except that they involve infima over different sets, and the first two are modified versions of a previously known variational formula (qVar0) for which we provide a short alternative proof. Then, we show that (qVar0) always has a minimizer, (aVar2) never has any minimizers unless the RWRP is an RWRE, and (aVar1) has a minimizer if and only if the RWRP is in the weak disorder regime. In the latter case, the minimizer of (aVar1) is unique and it is also the unique minimizer of (qVar1), but (qVar2) has no minimizers except for RWRE. In the case of strong disorder, we give a sufficient condition for the nonexistence of minimizers of (qVar1) and (qVar2) which is satisfied for the log-gamma directed polymer with a sufficiently small parameter. We end with a conjecture which implies that (qVar1) and (qVar2) have no minimizers under very strong disorder
Comment on “Quartic anharmonic oscillator and non-Hermiticity”
No full textThe analysis of the paper by J.-L. Chen et al. [Phys. Rev. A 67, 012101 (2003)] suffers from a conceptual error. Its results contradict some well-established mathematical facts and are incorrect
Intensity-modulated radiotherapy versus 3-dimensional conformal radiotherapy strategies for locally advanced non-small-cell lung cancer
No full textChemoradiotherapy is the current standard of care in patients with advanced inoperable stage IIIA or IIIB non-small cell lung cancer (NSCLC). Three-dimensional radiotherapy (3DCRT) has been a trusted method for a long time and has well-known drawbacks, most of which could be improved by Intensity Modulated Radiotherapy (IMRT). IMRT is not currently the standard treatment of locally advanced NSCLC, but almost all patients could benefit to a degree in organ at risk sparing, dose coverage conformality, or dose escalation. The most critical step for a radiation oncology department is to strictly evaluate its own technical and physical capabilities to determine the ability of IMRT to deliver an optimal treatment plan. This includes calculating the internal tumor motion (ideally 4DCT or equivalent techniques), treatment planning software with an up-todate heterogeneity correction algorithm, and daily image guidance. It is crucial to optimise and individualise the therapeutic ratio for each patient during the decision of 3DCRT versus IMRT. The current literature rationalises the increasing use of IMRT, including 4D imaging plus PET/CT, and encourages the applicable knowledge-based and individualised dose escalation using advanced daily image-guided radiotherapy
Recent advances in Takayasu's arteritis
No full textTakayasu’s arteritis (TAK) is a rare, chronic large-vessel vasculitis (LVV) that predominantly affects the aorta, its major branches, and the pulmonary arteries. Recent advances in the diagnosis, clinical course, disease assessment with biomarkers/imaging and new clinical tools, patient-reported outcomes, and new treatment options of TAK are discussed in this review. Conventional angiography, the gold standard method for initial diagnosis, appears to have been replaced with new imaging modalities such as magnetic resonance angiography (MRA) and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in recent years. MRA and FDG-PET are also promising for the assessment of disease activity. New tools for disease assessment such as Indian Takayasu’s Arteritis Score 2010 (ITAS2010) and color Doppler ultrasound (CDUS) aim to better characterize and quantify disease activity; however, different imaging modalities in routine follow-up are not incorporated sufficiently in these approaches. Prognosis is possibly getting better, with lower mortality in recent years; however, it is difficult to assess the widely different vascular intervention rates among the clinical series. Leflunomide, tumor necrosis factor (TNF)-α antagonists, and tocilizumab are new options for patients resistant to conventional therapies. There is a clear need to develop a validated set of outcome measures for use in clinical trials of TAK. The Outcome Measures in Rheumatology (OMERACT) Vasculitis Working Group has taken on this task, finished a Delphi exercise with experts, and aims to develop a core set of outcomes for LVV in accordance with OMERACT Filter 2.0
Challenges in the management of severe allergic asthma in the elderly
No full textLittle is known about the features of asthma and allergy in the elderly. A significant number of elderly patients with asthma have uncontrolled and severe asthma. This review aims to provide an analysis of the literature on the assessment and phenotype of severe allergic asthma in the elderly. Gaps and pitfalls in diagnostic and therapeutic approaches, as well as management of severe allergic asthma in the elderly, are also discussed
Pesg PNH diagnosis, follow-up and treatment guidelines
No full textPNH Education and Study Group (PESG) have been established in December 2013 as a non-profit, independent, medical organization www.pesg.org. Paroxysmal Nocturnal Hemoglobinuria (PNH) is a multi-systemic disease that should be treated with a multidisciplinary approach. Patients may apply to the clinics other than the hematology due to variability and diversity of clinical findings which lower the rate of diagnosis due to low awareness about PNH. PNH might be overlooked and diagnosis might be delayed. Regarding these, PESG was established with the collaboration of Immunology, Cardiology, Thorax Diseases (Pulmonology), Neurology, Gastroenterology, General Surgery and Urology specialists in addition to hematologists dealing with PNH. The PESG study group aims to increase the awareness about PNH, including training activities about PNH, strengthening the relations between clinics and planning of clinical studies as a goal. It is the first professional organization focusing on PNH, in Turkey.In this guideline, we want to facilitate the diagnosis attributes of physicians from all specializations that deal with PNH and its systemic complications. One can perceive this as a tailor made guideline of international guidelines but not a compilation
Erratum to: Comparison of the trifecta outcomes of robotic and open nephron-sparing surgeries performed in the robotic era of a single institution
No full textTurkey’s two elections: the AKP comes back
No full textIn power since 2002, the Justice and Development Party (AKP) of Recep Tayyip Erdogan seemed as if it might be losing its hold when Turkish voters went to the polls in June 2015. Yet that “hung election” gave way to another contest in November, and the AKP came roaring back. © 2016 National Endowment for Democracy and Johns Hopkins University Press
Ottoman Royal Women's Spaces the Acoustic Dimension
No full textIn their discussion of space in relation to gender, historians of women in the Middle East so far have focused primarily on physical and visual access. This paper argues that women's acoustic space merits closer consideration, especially since acoustic methods of communication very often could and did exceed the limits of vision and visually bounded space. This argument is based on three different case studies concerning Ottoman royal women of the sixteenth and seventeenth centuries: (1) harem women's auditory access to imperial council meetings; (2) common petitioners' auditory access to the mother of the sultan as she traveled by carriage through the imperial capital during her frequent processions; and (3) Qur'anic recitation and prayers as commissioned by female mosque patrons. These case studies have more wide-ranging implications in that they allow for conceptual experimentation leading towards a refinement of the categories of private/public, male/female space, based on the permeability of acoustic space