Non-malleable codes for space-bounded tampering

Non-malleable codes—introduced by Dziembowski, Pietrzak and Wichs at ICS 2010—are key-less coding schemes in which mauling attempts to an encoding of a given message, w.r.t. some class of tampering adversaries, result in a decoded value that is either identical or unrelated to the original message. Such codes are very useful for protecting arbitrary cryptographic primitives against tampering attacks against the memory. Clearly, non-malleability is hopeless if the class of tampering adversaries includes the decoding and encoding algorithm. To circumvent this obstacle, the majority of past research focused on designing non-malleable codes for various tampering classes, albeit assuming that the adversary is unable to decode. Nonetheless, in many concrete settings, this assumption is not realistic

Quantum correlations in Newtonian space and time: arbitrarily fast communication or nonlocality

We investigate possible explanations of quantum correlations that satisfy the principle of continuity, which states that everything propagates gradually and continuously through space and time. In particular, following [J.D. Bancal et al, Nature Physics 2012], we show that any combination of local common causes and direct causes satisfying this principle, i.e. propagating at any finite speed, leads to signalling. This is true even if the common and direct causes are allowed to propagate at a supraluminal-but-finite speed defined in a Newtonian-like privileged universal reference frame. Consequently, either there is supraluminal communication or the conclusion that Nature is nonlocal (i.e. discontinuous) is unavoidable.Comment: It is an honor to dedicate this article to Yakir Aharonov, the master of quantum paradoxes. Version 2 contains some more references and a clarified conclusio

Causality - Complexity - Consistency: Can Space-Time Be Based on Logic and Computation?

The difficulty of explaining non-local correlations in a fixed causal structure sheds new light on the old debate on whether space and time are to be seen as fundamental. Refraining from assuming space-time as given a priori has a number of consequences. First, the usual definitions of randomness depend on a causal structure and turn meaningless. So motivated, we propose an intrinsic, physically motivated measure for the randomness of a string of bits: its length minus its normalized work value, a quantity we closely relate to its Kolmogorov complexity (the length of the shortest program making a universal Turing machine output this string). We test this alternative concept of randomness for the example of non-local correlations, and we end up with a reasoning that leads to similar conclusions as in, but is conceptually more direct than, the probabilistic view since only the outcomes of measurements that can actually all be carried out together are put into relation to each other. In the same context-free spirit, we connect the logical reversibility of an evolution to the second law of thermodynamics and the arrow of time. Refining this, we end up with a speculation on the emergence of a space-time structure on bit strings in terms of data-compressibility relations. Finally, we show that logical consistency, by which we replace the abandoned causality, it strictly weaker a constraint than the latter in the multi-party case.Comment: 17 pages, 16 figures, small correction

ESPRESSO: The next European exoplanet hunter

The acronym ESPRESSO stems for Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations; this instrument will be the next VLT high resolution spectrograph. The spectrograph will be installed at the Combined-Coud\'e Laboratory of the VLT and linked to the four 8.2 m Unit Telescopes (UT) through four optical Coud\'e trains. ESPRESSO will combine efficiency and extreme spectroscopic precision. ESPRESSO is foreseen to achieve a gain of two magnitudes with respect to its predecessor HARPS, and to improve the instrumental radial-velocity precision to reach the 10 cm/s level. It can be operated either with a single UT or with up to four UTs, enabling an additional gain in the latter mode. The incoherent combination of four telescopes and the extreme precision requirements called for many innovative design solutions while ensuring the technical heritage of the successful HARPS experience. ESPRESSO will allow to explore new frontiers in most domains of astrophysics that require precision and sensitivity. The main scientific drivers are the search and characterization of rocky exoplanets in the habitable zone of quiet, nearby G to M-dwarfs and the analysis of the variability of fundamental physical constants. The project passed the final design review in May 2013 and entered the manufacturing phase. ESPRESSO will be installed at the Paranal Observatory in 2016 and its operation is planned to start by the end of the same year.Comment: 12 pages, figures included, accepted for publication in Astron. Nach

Peripheral blood mono-nuclear cells implantation in patients with Peripheral Arterial Disease: a pilot study for clinical and biochemical outcome of neoangiogenesis.

BACKGROUND: Substantial progresses in the management of peripheral arterial disease (PAD) have been made in the past two decades. Progress in the understanding of the endothelial-platelet interaction during health and disease state has resulted in better antiplatelet drugs that can prevent platelet aggregation, activation and thrombosis during angioplasty and stenting. A role in physiological and pathological angiogenesis in adults has been recently shown in bone marrow–derived circulating endothelial progenitors (BM-DCEPs) identified in the peripheral blood. These findings have paved the way for the development of therapeutic neovascularization techniques using endothelial progenitors. METHODS: This pilot study includes five patients, aged 60 to 75, with a history of claudication and recruited from September 2010 to February 2011 at the A.O.U. Federico II of Naples. PBMNCs have been implanted three times in the limb with the worst ABI value in all the patients included in the study. The clinical follow up was performed during the subsequent 12 months from the beginning of the treatment. RESULTS: In four patients there was a regression of ulcerative lesions. One patient’s condition improved after the first implantation but later did not respond to the further treatments. All patients achieved a pain relief as judged by the numeric pain scale. Pain relief remained satisfactory in three patients for one year. Pain gradually returned to the pre-treatment level in two patients. All patients referred an ameliorating in their quality of life expressed even by an improvement in claudication free walking distance. These improvements are reflected also by intra-arterial digital subtraction angiography (IADSA) that shows an improvement of arterial vascularization. CONCLUSIONS: The data from this study suggest an efficacy of BM-DCEPs implantation in terms of improvement of the vascularization and quality of life in patients affected by Peripheral Arterial Disease. Nevertheless a double-blind placebo-controlled study is needed to confirm our findings

Procalcitonin: a possible marker of invasive fungal infection in high risk patients?

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The prevalence of diabetes and stress hyperglycemia in the acute myocardial infarction patients

OBJETIVOS: Determinar a prevalência do diabetes melito (DM) e da hiperglicemia de estresse (HE) em pacientes com infarto agudo do miocárdio (IAM) admitidos em unidade de emergência cardiológica. MÉTODOS: Análise retrospectiva de 2.262 pacientes com IAM, avaliando, além da prevalência de diabetes referido, o diagnosticado e a hiperglicemia de estresse. RESULTADOS: Apesar de referido em 12,1% dos pacientes (H: 10,7%, M: 15,8%), o DM ocorria efetivamente em 24,8% (H: 22,9%, M: 29,7%) e a HE em 13,6% (H: 14,3%, M: 11,7%) dos indivíduos dessa população. Portanto, alterações glicêmicas ocorreram em 37,4% dos indivíduos com IAM (H: 37,2%, M: 41,4%). Nos pacientes com DM, observou-se maior precocidade etária do IAM, maior prevalência de óbitos (DM: 20,7%, ND:13,8%, HE: 13,4%) e de procedimentos cirúrgicos (ND: 33,8%, HE: 18,0%, DM: 21,7%). CONCLUSÃO: A elevada prevalência de DM e hiperglicemia de estresse observada em nosso estudo indica que as alterações glicêmicas constituem um dos mais importantes fatores de risco para o IAM.OBJECTIVES: To evaluate in our population the real prevalence of diabetes (DM) and stress hyperglycemia (HE) in patients with myocardial infarction (IAM) admitted in a cardiologic emergency unit. METHODS: A retrospective analysis of 2262 patients with AMI evaluating the prevalence of DM (referred and diagnosed) and stress hyperglycemia. RESULTS: Besides 12,1% of subjects were previously referred to be diabetic (men: 10.7% and women: 15.8%), diabetes was effectively diagnosed in 24,8% (M: 22,9%, W: 29,7%) and stress hyperglycemia in 13,6% HE of the patients (M: 14,3%, W: 11,7%) indicating that glycemic alterations were effectively observed in 37.2.% of the patients with IAM (M: 37,2%, W: 41,4%). In DM subjects IAM events occurred earlier, total intra-hospital mortality was higher (DM: 20.7%, ND: 13,8%, HE: 13,4%) and less surgical procedures were performed (ND 33.8%, DM: 21.7%, HE: 18.0%). CONCLUSION: The elevated DM and stress hyperglycemia prevalence observed in our study indicates that glycemic alterations is one of the most important risk factors for IAM

Pilot study on the antibacterial activity of hydrogen peroxide and silver ions in the hospital environment

BACKGROUND: Nosocomial environmental contamination plays an important role in the transmission of several health care-associated pathogens. Control of surfaces contamination can reduce the risk of cross-infection in hospitals. The aim of our study is to evaluate the disinfectant effectiveness of hydrogen peroxide and silver ions, against nosocomial multidrug-resistant strains, when it's used directly on surfaces. METHODS: Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 15442 and the same multidrug-resistant clinical isolates were selected to study the effectiveness of the disinfectant used in suspension or on the clean and dirty surface. RESULTS: Regarding the suspension activity test, the hydrogen peroxide and silver ions resulted effective after 5 min for ATCC strains and after 10 min for multidrug-resistant isolates; about the surface activity test, its action resulted after 10 min for ATCC strains and after 15 min for multidrug-resistant isolates. Moreover, it was more effective when used in the absence or in presence of a low concentration of biological materials. CONCLUSIONS: In a complex environment such as hospital wards, to have a disinfectant notoriously effective but more easy and quick to use would be an useful solution to treat small surfaces occasionally contaminated by biological materials

Updatable Blockchains

Software updates for blockchain systems become a real challenge when they impact the underlying consensus mechanism. The activation of such changes might jeopardize the integrity of the blockchain by resulting in chain splits. Moreover, the software update process should be handed over to the community and this means that the blockchain should support updates without relying on a trusted party. In this paper, we introduce the notion of updatable blockchains and show how to construct blockchains that satisfy this definition. Informally, an updatable blockchain is a secure blockchain and in addition it allows to update its protocol preserving the history of the chain. In this work, we focus only on the processes that allow securely switching from one blockchain protocol to another assuming that the blockchain protocols are correct. That is, we do not aim at providing a mechanism that allows reaching consensus on what is the code of the new blockchain protocol. We just assume that such a mechanism exists (like the one proposed in NDSS 2019 by Zhang et. al), and show how to securely go from the old protocol to the new one. The contribution of this paper can be summarized as follows. We provide the first formal definition of updatable ledgers and propose the description of two compilers. These compilers take a blockchain and turn it into an updatable blockchain. The first compiler requires the structure of the current and the updated blockchain to be very similar (only the structure of the blocks can be different) but it allows for an update process more simple, efficient. The second compiler that we propose is very generic (i.e., makes few assumptions on the similarities between the structure of the current blockchain and the update blockchain). The drawback of this compiler is that it requires the new blockchain to be resilient against a specific adversarial behaviour and requires all the honest parties to be online during the update process. However, we show how to get rid of the latest requirement (the honest parties being online during the update) in the case of proof-of-work and proof-of-stake ledgers

Oral sodium butyrate supplementation ameliorates paclitaxel-induced behavioral and intestinal dysfunction

Paclitaxel (PTX) is one of the most broadly used chemotherapeutic agents for the treatment of several tumor types including ovarian, breast, and non-small cell lung cancer. However, its use is limited by debilitating side effects, involving both gastrointestinal and behavioral dysfunctions. Due to growing evidence showing a link between impaired gut function and chemotherapy-associated behavioral changes, the aim of this study was to identify a novel therapeutic approach to manage PTX-induced gut and brain comorbidities. Mice were pre-treated with sodium butyrate (BuNa) for 30 days before receiving PTX. After 14 days, mice underwent to behavioral analysis and biochemical investigations of gut barrier integrity and microbiota composition. Paired evaluations of gut functions revealed that the treatment with BuNa restored PTX-induced altered gut barrier integrity, microbiota composition and food intake suggesting a gut-to-brain communication. The treatment with BuNa also ameliorated depressive- and anxiety-like behaviors induced by PTX in mice, and these effects were associated with neuroprotective and anti-inflammatory outcomes. These results propose that diet supplementation with this safe postbiotic might be considered when managing PTX-induced central side effects during cancer therapy