Uncertainty principle, positivity and Lp-boundedness for generalized spectrograms

AbstractIn this paper we are concerned with the properties of positivity, uncertainty principle and continuity in Lp spaces of a generalized spectrogram. In particular we study the connections of a generalized spectrogram, as a subclass of the Cohen class, with the Rihaczek and the Wigner representations. We also consider the behavior of the generalized spectrogram with respect to the positivity and the Lp boundedness of the corresponding localization operators

Overview of the NSTX Control System

The National Spherical Torus Experiment (NSTX) is an innovative magnetic fusion device that was constructed by the Princeton Plasma Physics Laboratory (PPPL) in collaboration with the Oak Ridge National Laboratory, Columbia University, and the University of Washington at Seattle. Since achieving first plasma in 1999, the device has been used for fusion research through an international collaboration of over twenty institutions. The NSTX is operated through a collection of control systems that encompass a wide range of technology, from hardwired relay controls to real-time control systems with giga-FLOPS of capability. This paper presents a broad introduction to the control systems used on NSTX, with an emphasis on the computing controls, data acquisition, and synchronization systems.Comment: 3 PDF pages, 8th International Conference on Accelerator and Large Experimental Physics Control Systems (PSN TUBT004), San Jose, CA, USA, November 27-3

War, human rights, and medical scientific publishing: European Journal of Physical and Rehabilitation Medicine will accept from now on only papers by authors signing the UN Declaration on Human Rights

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Direct Telemetry Access

Fine-grained network telemetry is becoming a modern datacenter standard and is the basis of essential applications such as congestion control, load balancing, and advanced troubleshooting. As network size increases and telemetry gets more fine-grained, there is a tremendous growth in the amount of data needed to be reported from switches to collectors to enable network-wide view. As a consequence, it is progressively hard to scale data collection systems.We introduce Direct Telemetry Access (DTA), a solution optimized for aggregating and moving hundreds of millions of reports per second from switches into queryable data structures in collectors' memory. DTA is lightweight and it is able to greatly reduce overheads at collectors. DTA is built on top of RDMA, and we propose novel and expressive reporting primitives to allow easy integration with existing state-of-the-art telemetry mechanisms such as INT or Marple.We show that DTA significantly improves telemetry collection rates. For example, when used with INT, it can collect and aggregate over 400M reports per second with a single server, improving over the Atomic MultiLog by up to 16x

Characterization of the Channel Constriction Allowing the Access of the Substrate to the Active Site of Yeast Oxidosqualene Cyclase

In oxidosqualene cyclases (OSCs), an enzyme which has been extensively studied as a target for hypocholesterolemic or antifungal drugs, a lipophilic channel connects the surface of the protein with the active site cavity. Active site and channel are separated by a narrow constriction operating as a mobile gate for the substrate passage. In Saccharomyces cerevisiae OSC, two aminoacidic residues of the channel/constriction apparatus, Ala525 and Glu526, were previously showed as critical for maintaining the enzyme functionality. In this work sixteen novel mutants, each bearing a substitution at or around the channel constrictions, were tested for their enzymatic activity. Modelling studies showed that the most functionality-lowering substitutions deeply alter the H-bond network involving the channel/constriction apparatus. A rotation of Tyr239 is proposed as part of the mechanism permitting the access of the substrate to the active site. The inhibition of OSC by squalene was used as a tool for understanding whether the residues under study are involved in a pre-catalytic selection and docking of the substrate oxidosqualene

Bronchial carcinoid tumors: surgical management and long-term outcome

OBJECTIVE: We sought to determine the variables influencing long-term survival of patients treated for bronchial carcinoid tumors. METHODS: A retrospective, mono-institutional review of patients subjected to surgical treatment since 1977 was conducted. RESULTS: Over 22 years, 126 patients with a final histologic diagnosis of bronchial carcinoid tumors were assessed for surgery. The group comprised 72 men (57%) and 54 women (43%) with a mean age at presentation of 47 +/- 16 years (range 11-77 years). Symptoms were present in 65 (53%) patients. Operations included lobectomy or bilobectomy in 88 (with 4 bronchoplastic procedures), pneumonectomy in 15, segmentectomy in 3, wedge resection in 16, and bronchial sleeve resection in 3 patients. One patient (0.7%) died in the perioperative period. Eighty-two patients (65%) had typical and 44 (35%) had atypical carcinoid tumors. Postoperative staging was complete for 113 of 126 patients (13 patients did not undergo lymphadenectomy): 90 patients had stage I disease, 6 had stage II, 15 had stage III, and 2 had stage IV disease. A typical subtype was stage I in 70 and more advanced (II-IV) in 5, whereas an atypical subtype was stage I in 20 and more advanced in 18 (P <.05). Mean follow-up was 99 +/- 73 months (range 6-282 months) during which 19 (15%) patients died (12 of recurrent disease). Recurrent tumor developed in 4 (5.5%) of 72 patients affected by typical subtypes and 8 (19.5%) of 41 by atypical subtypes with complete follow-up. Overall survival at 15 years was 74%; survival related to histologic type and nodal status at 15 years was significant (P <.05). CONCLUSIONS: Biologic behavior and prognosis for bronchial carcinoid tumors are better than for other lung cancers. Surgical treatment requires radical excision and lymph node sampling. Survival and long-term outcome are significantly related to the histologic type, nodal status, and pathologic stage

Solitary fibrous tumour of the pleura: surgical treatment

OBJECTIVE: Solitary fibrous tumours (SFT) of the pleura are rare tumours originated from the mesenchimal tissue underlying the mesothelial layer of the pleura. This tumours present unpredictable clinical course probably related to their histological and morphological characteristics. METHODS: Twenty-one patients affected by SFT of the pleura were referred to us for surgical resection from September 1984 to April 2000. They were 15 males and six females with median age of 51 (range 15--73) years. Nine patients (43%) were symptomatic and predominant clinical symptoms or signs were dyspnoea (19%), coughing (14.3%), chest pain (28.5%), finger clubbing (14.3%) and hypoglycaemia (14.3%). Hypoglycaemia was related to a pathological incretion of insulin-like growth factor 2 by the tumour. Chest radiograph and computed tomography of the chest revealed intra-thoracic homogeneous sharply delineated round or lobulated mass sometimes associated with ipsilateral pleural effusion (19%) or causing pulmonary atelectasis with opacification of the complete hemithorax (19%). Surgical excision required 14 posterolateral thoracotomies, six anterior thoracotomies and one video-assisted thoracoscopy. Thirteen tumours arose from visceral pleura and wedge resection was performed, seven tumours arose from parietal pleura and extrapleural resection was carried out without any chest-wall resection, one tumour growth within the upper left lobe and required lobectomy. Tumours weighted from 22 to 1942 g and measured from 22x12x8 to 330x280x190 mm. At cut section seven cases (34%) revealed focal necrosis and hemorrhagic zones and on light microscopy six cases (28.5%) were characterized by high mitotic count: characteristics related with uncertain clinical behaviour. Immuno-histochemical reactions were in all cases positive for CD34. RESULTS: In all our patients resections were complete. Paraneoplastic syndromes like hypoglycaemia and clubbing receded after surgery. No intraoperative or perioperative medical or surgical complications occurred. Median chest-drain duration timed 3 (range 2--5) days and median hospital stay was 5 (range 4--7) days. Perioperative mortality rate was 0%. Median follow-up was 68 (range 2--189) months: during this period patients were submitted to chest X-ray with 6-months interval to evaluate possible local recurrence. Only one patient experienced tumour recurrence after 124 months follow-up: the tumour was suspected after observation of finger clubbing. The tumour was detected and excised by redo-thoracotomy. CONCLUSIONS: Surgical resection of benign solitary fibrous tumours is usually curative, but local recurrences can occur years after seemingly adequate surgical treatment. Malignant solitary fibrous tumours generally have a poor prognosis. Clinical follow-up and radiological follow-up are indicated for both benign and malignant solitary fibrous tumours