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We demonstrate a smart image-packaging optical technique that uses what we believe is a new concept to save byte space when transmitting data. The technique supports a large set of images mapped into modulated speckle patterns. Then, they are multiplexed into a single package. This operation results in a substantial decreasing of the final amount of bytes of the package with respect to the amount resulting from the addition of the images without using the method. Besides, there are no requirements on the type of images to be processed. We present results that proof the potentiality of the technique.

We introduce for the first time the concept of an all-optical encrypted movie. This movie joints several encrypted frames corresponding to a time evolving situation employing the same encoding mask. Thanks to a multiplexing operation we compact the encrypted movie information into a single package. But the decryption of this single package implies the existence of cross-talk if we do not adequately pre-process the encoded information before multiplexing. In this regard, we introduce a grating modulation to each encoded image, and then we proceed to multiplexing. After appropriate filtering and synchronizing procedures applied to the multiplexing, we are able to decrypt and to reproduce the movie. This movie is only properly decoded when in possession of the right decoding key. The concept development is carried-out in virtual optical systems, both for the encrypting and the filtering-decrypting stages. Experimental results are shown to confirm our approach.

Clopidogrel has been used (alone or in association with aspirin) to prevent vascular complications in atherothrombotic patients, to prevent stent thrombosis (ST) in patients undergoing percutaneous coronary intervention (PCI) and as a long-term prevention of cardiovascular and cerebrovascular events. Unfortunately, it is important to note that there are a number of patients who, during clopidogrel therapy, show and maintain a high platelet reactivity (PR), similar to that observed before the start of antiplatelet therapy. Clopidogrel pro-drug is absorbed in the intestine and this process is influenced by P-glycoprotein-1 (P-GP). Its conversion into 2-oxo clopidogrel is regulated by cytochromes (CYP) called CYP2C19, CYP2B6 and CYP1A2. Whereas, the final transformation into the active metabolite is regulated by CYP called CYP2C19, CYP2C9, CYP2B6, CYP3A4, CYP3A5 and, as recently emerged, by the glycoprotein paraoxonase-1 (PON1). The genes encoding these enzymes are characterized by several polymorphisms. Some of these are able to modify the activity of proteins, reducing the concentration of active metabolite and the values of on-clopidogrel PR. Only one gene polymorphism (CYP2C19*17) increases the clopidogrel metabolization and so the clopidogrel-induced platelet inhibition. Several studies have clearly associated these gene polymorphisms to both ischemic and bleeding complications in patients receiving dual antiplatelet therapy. The aim of this review is to describe the principal gene polymorphisms influencing on-clopidogrel PR and their relationship with long-term clinical outcome.

Background: The optimal duration of clopidogrel therapy after coronary stenting is debated because of the scarcity of randomized controlled trials and inconsistencies arising from registry data. Although prolonged clopidogrel therapy after bare metal stenting is regarded as an effective secondary prevention measure, the safety profile of drug-eluting stents itself has been questioned in patients not receiving ≥ 12 months of dual-antiplatelet therapy., Hypothesis: Twenty-four months of clopidogrel therapy after coronary stenting reduces the composite of death, myocardial infarction, or stroke compared with 6 months of treatment., Study Design: PRODIGY is an unblinded, multicenter, 4-by-2 randomized trial. All-comer patients with indication to coronary stenting are randomly treated-balancing randomization-with bare metal stent (no active late loss inhibition), Endeavor Sprint zotarolimus-eluting stent (Medtronic, Santa Rosa, CA) (mild late loss inhibition), Taxus paclitaxel-eluting stent (Boston Scientific, Natick, MA) (moderate late loss inhibition), or Xience V everolimus-eluting stent (Abbott Vascular, Santa Clara, CA) (high late loss inhibition). At 30 days, patients in each stent group are randomly allocated to receive 24 or up to 6 months of clopidogrel therapy-primary end point randomization. With 1,700 individuals, this study will have >80% power to detect a 40% difference in the primary end point after sample size augmentation of 5% and a background event rate of 8%., Summary: The PRODIGY trial aims to assess whether 24 months of clopidogrel therapy improves cardiovascular outcomes after coronary intervention in a broad all-comer patient population receiving a balanced mixture of stents with various anti-intimal hyperplasia potency., (Copyright © 2010 Mosby, Inc. All rights reserved.)

We demonstrate in this Letter that a joint transform correlator shows vulnerability to known-plaintext attacks. An unauthorized user, who intercepts both an object and its encrypted version, can obtain the security key code mask. In this contribution, we conduct a hybrid heuristic attack scheme merge to a Gerchberg-Saxton routine to estimate the encrypting key to decode different ciphertexts encrypted with that same key. We also analyze the success of this attack for different pairs of plaintext-ciphertext used to get the encrypting code. We present simulation results for the decrypting procedure to demonstrate the validity of our analysis.

Antiplatelet therapy is the cornerstone of treatment for patients with acute coronary syndromes and/or undergoing percutaneous coronary interventions (PCI). Clopidogrel, a thienopyridine antiplatelet agent, has been used to prevent vascular complication in atherothrombotic patients, to prevent stent thrombosis in patients undergoing PCI, and in long term prevention of cardiovascular and cerebrovascular events. More than 40 million patients in the world receive clopidogrel but unfortunately about 20% of these are either non or poor responders. Several methods have been used to assess clopidogrel-induced antiplatelet effects. However, none of these tests have been fully standardized or fully agreed upon to measure clopidogrel responsiveness. Nevertheless, many studies using different techniques, platelet agonists and definitions, showed that patients with a poor response to clopidogrel have an increased risk of death, reinfarction and stent thrombosis. The mechanisms leading to poor responsiveness are not fully clarified and are likely multifactorial: genetic factors, accelerated platelet turnover, up-regulation of the P2Y(12) pathways, high baseline platelet reactivity, poor compliance, under-dosing and drug-drug interactions. The management of these patients is very difficult, but some evidence showed that a strategy of higher maintenance dose or switch to different thienopyridine (e.g. ticlopidine or prasugrel) or use of glycoprotein IIb/IIIa inhibitors during PCI may be helpful to overcome poor responsiveness and improve the long-term clinical outcome. This paper reviews the impact of clopidogrel poor responsiveness on clinical outcomes, the mechanisms leading to poor effect and the different assays to assess it. Finally, current and future options for its management is discussed.

Importance of the Field: Heightened platelet activity is pivotal in the thrombosis underlying acute coronary syndrome (ACS). The glycoprotein IIb/IIIa inhibitor tirofiban is a powerful platelet inhibitor with demonstrated efficacy and safety across the spectrum of ACS. Despite tirofiban's impact on the platelet compared with placebo, only an excess in minor and importantly not major bleeding has been observed. Thrombocytopenia with tirofiban seems to be extremely rare and immediately reversible on infusion discontinuation., Areas Covered in This Review: The review includes the rationale for potent antiplatelet therapy in the management of ACS, particularly patients at high risk for ischemic complications. Additionally, it provides an overview of tirofiban's pharmacology and summary of the clinical efficacy and safety data of two dosing regimens., What the Reader Will Gain: The reader will gain a perspective on the efficacy and safety data from the key trials of tirofiban., Take Home Message: Tirofiban is safe and effective in patients with ACS. The single bolus dose regimen produces potent platelet inhibition resulting in significant improvement in clinical events over placebo when initiated just prior to percutaneous coronary intervention and at first medical contact. When compared with abciximab, tirofiban demonstrates similar efficacy though significantly lower rates of thrombocytopenia.

Aims: To perform a thorough and updated systematic review of randomized clinical trials comparing tirofiban vs. placebo or vs. abciximab., Methods and Results: We searched for randomized trials comparing tirofiban vs. placebo or any active control. Odds ratios (OR) were computed from individual studies and pooled with random-effect methods. Thirty-one studies were identified involving 20,006 patients (12 874 comparing tirofiban vs. heparin plus placebo or bivalirudin alone, and 7132 vs. abciximab). When compared with placebo, tirofiban was associated at 30 days with a significant reduction in mortality [OR = 0.68 (0.54-0.86); P = 0.001] and death or myocardial infarction (MI) [OR = 0.69 (0.58-0.81); P < 0.001]. The treatment benefit persisted at follow-up but came at an increased risk of minor bleedings [OR = 1.42 (1.13, 1.79), P = 0.002] or thrombocytopenia. When compared with abciximab, mortality at 30 days did not differ [OR = 0.90 (0.53, 1.54); P = 0.70], but in the overall group tirofiban trended to increase the composite of death or MI [OR = 1.18 (0.96, 1.45); P = 0.11]. No such trend persisted at medium-term follow-up or when appraising studies testing tirofiban at 25 microg/kg bolus regimen., Conclusion: Tirofiban administration reduces mortality, the composite of death or MI and increases minor bleedings when compared with placebo. An early ischaemic hazard disfavouring tirofiban was noted when compared with abciximab in studies based on 10 but not 25 microg/kg tirofiban bolus regimen.

We show that multiple secure data recording under a wavelength multiplexing technique is possible in a joint transform correlator (JTC) arrangement. We evaluate both the performance of the decrypting procedure and the influence of the input image size when decrypting with a wavelength different from that employed in the encryption step. This analysis reveals that the wavelength is a valid parameter to conduct image multiplexing encoding with the JTC architecture. In addition, we study the influence of the minimum wavelength change that prevents decoding cross talk. Computer simulations confirm the performance of the proposed technique.

We propose the use of fractal structured diffractive masks as keys in secure storage-readout systems. A joint transform correlator based on a photorefractive crystal in the Fourier domain is implemented to perform encryption and decryption. We discuss the advantages of encrypting information using this kind of deterministic keys in comparison to conventional random phase masks. Preliminary experimental results are presented to demonstrate the effectiveness of the proposed system.

We propose a multichanneling encryption method by using multiple random-phase mask apertures in the input plane based on a joint transform correlation scheme. In the proposal, this multiple aperture arrangement is changed as different input objects are inserted and stored. Then, during the decryption step, the appropriate use of the random-phase mask apertures can ensure the retrieval of different information. This approach provides different access levels. Computer simulations show the potential of the technique and experimental results verify the feasibility of this method.

Objectives: From an Italian Registry of patients with upper gastrointestinal hemorrhage (UGIH), we assessed the clinical outcomes and explored the roles of clinical, endoscopic, and therapeutic factors on 30-day mortality in a real life setting., Methods: Prospective analysis of consecutive patients endoscoped for UGIH at 23 community and tertiary care institutions from 2003 to 2004. Covariates and outcomes were defined a priori and 30-day follow-up obtained. Logistic regression analysis identified predictors of mortality., Results: One thousand and twenty patients were included. A total of 46 patients died for an overall 4.5% mortality rate. In all, 85% of deaths were associated with one or more major comorbidity. Sixteen of 46 patients (35%) died within the first 24 h of the onset of bleeding. Of these, eight had been categorized as ASA class 1 or 2 and none of them was operated upon, despite a failure of endoscopic intention to treatment in four. Regression analysis showed advanced age, presence of severe comorbidity, low hemoglobin levels at presentation, and worsening health status as the only independent predictors of 30-day mortality (P < 0.001). The acute use of a PPI exerted a protective effect (OR 0.23, 95% CI 0.09-0.73). Recurrent bleeding was low (3.2%). Rebleeders accounted for only 11% of the total patients deceased (OR 3.27, 95% CI 1.5-11.2)., Conclusions: These results indicate that 30-day mortality for nonvariceal bleeding is low. Deaths occurred predominantly in elderly patients with severe comorbidities or those with failure of endoscopic intention to treatment.

Platelet reactivity plays a pivotal role in the pathogenesis of ischemic adverse events during and after acute coronary syndromes (ACS), and percutaneous coronary intervention (PCI). Glycoprotein (GP) IIb/IIIa inhibitors are the strongest antiplatelet agents currently available on the market and three different compounds, namely abciximab, tirofiban, and eptifibatide, have been approved for clinical use. Abciximab has been investigated in the clinical field far more extensively than the other GPIIb/IIIa inhibitors. Abciximab is an anti-integrin Fab fragment of a human - mouse chimeric monoclonal antibody with high affinity and a slow dissociation rate from the GP IIb/IIIa platelet receptor. Abciximab, given shortly before the coronary intervention, is superior to placebo in reducing the acute risk of ischemic complications (EPIC, EPISTENT, EPILOG trials); moreover, in the ISAR-REACT 2 study abciximab has been shown to reduce the risk of adverse events in patients with non ST-segment elevation ACS who are undergoing PCI even after optimal pre-treatment with 600 mg of clopidogrel. Finally, abciximab has been also used in abciximab-coated stent, with only bolus administration regimen and for direct intracoronary use with promising results that may extend and/or modify its current use in clinical practice in future.

The use of different pupils for storing each speckled image in speckle photography is employed to determine multiple in-plane rotations. The method consists of recording a four-exposure specklegram where the rotations are done between exposures. This specklegram is then optically processed in a whole field approach rendering isothetic fringes, which give detailed information about the multiple rotations. It is experimentally demonstrated that the proposed arrangement permits the depiction of six isothetics in order to measure either six different angles or three nonparallel components for two local general in-plane displacements.

A theoretical analysis on wave propagation and optical properties of slabs with light-induced free charge carriers within a Fabry-Pérot framework is presented. The key of the analysis is to attack the wave propagation problem in terms of the time-averaged Poynting vector modulus within the medium through an alternative approach. This fact allows coupling the microscopic (free charge rate) and macroscopic (electromagnetic field evolution) equations self-consistently by means of the nonlinear permittivity and conductivity, which, in turn, depend on the time-averaged Poynting vector modulus. Thereby, the transmittance, reflectance, and absorptive power are derived as functions of the pump intensity and medium thickness. Bistable behavior is found at relatively high excitation intensity for positive values of the nonlinear permittivity coefficient. The bistability enhances for increasing values of such coefficient and weakens for increasing values of nonlinear photoconductivity coefficient. On the contrary, for negative nonlinear permittivity coefficient, bistability does not appear possessing these media mirrorlike behavior. Some possible applications are suggested.

We study the properties of a double-exposure image specklegram of a diffuse object obtained by use of a double-aperture pupil. A phase object is placed in front of one aperture during the first or the second exposure. Also, it is assumed that a uniform displacement of the diffuser between exposures is produced. The recorded specklegram is coherently illuminated and analyzed by Fourier transform operations. The average intensity distribution and the interference fringe visibility in the Fourier plane are investigated. On this basis, an alternative interference technique to detect phase objects is proposed.

We describe the characteristics of a double-exposure specklegram obtained through a double-aperture system, by introduction of a wedge in front of one aperture in one exposure. It is assumed that a uniform displacement of the diffuser is produced between exposures. The average intensity distribution and visibility of the interferometric fringes in the Fourier plane are analyzed. An alternative interferometric technique for phase-object detection is proposed.

An optical setup to obtain all the fractional correlations of a one-dimensional input in a single display is implemented. The system works as a multichannel parallel correlator for a continuous set of fractional orders and presents a variable shift variance. Some experimental results together with computer simulations are performed to illustrate the performance of our proposal.

The use of different multiple-aperture pupils for recording each image in speckle photography is proposed. The introduction of suitable spatial frequency carriers, by internally modulating imaged speckles, allows one to selectively isolate or combine the spectral content of different images into spatially separated regions in the Fourier plane. Theoretical and experimental results extend the speckle photography technique to the depiction of several specklegrams of multiple uniform in-plane displacements. In this case, because different pupils are considered for recording, the cross-correlation functions for the amplitudes and intensities in the image plane are calculated on the basis of the statistical properties of the object. Also, the ensemble-average intensity in the Fourier plane is analytically derived, and fringe visibility is investigated.

The medical care of the idiopathic constipation requires the correct patient identification based on precise classification items and on physiopathological considerations. The laxative abuse is often the most difficult problem to be solved and it has to be dealt with the consideration of different clinical aspects (wrong diet, psychological profile, concomitant diseases, drug therapy, etc.). The first step exactly consists in the identification and correction of the wrong convictions, of the behavioural attitudes and of the unbalanced dietary habits. Adding bran is the second widely accepted therapeutic step based on both physiopathological and epidemiological considerations. Even if the mechanism of action is still not completely understood, the fibre addition per se leads to an improvement of the constipation in quite a relevant percentage of patients, although it is often poorly tolerated. Nevertheless there are peculiar conditions not responsive to the bran addition such as the so-called "anismus". For these situations different therapeutic approaches have been proposed with variable results. Among these we can mention the re-educational programmes of the modalities of the defecation using biofeedback techniques. The chronic idiopathic constipation not respondent to the conventional medical therapy appears anyway a problematic and very difficult condition both from the investigational viewpoint and the therapeutic options. Finally it can be stated that the laxatives have a certain role in those clinical conditions most probably leading to the constipation. For each therapeutic drug class it is, of course, of great importance to know its mode of action as well as its adverse event profile.