293 research outputs found

    Universally Scalable Concurrent Data Structures

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    The increase in the number of cores in processors has been an important trend over the past decade. In order to be able to efficiently use such architectures, modern software must be scalable: performance should increase proportionally to the number of allotted cores. While some software is inherently parallel, with threads seldom having to coordinate, a large fraction of software systems are based on shared state, to which access must be coordinated. This shared state generally comes in the form of a concurrent data structure. It is thus essential for these concurrent data structures to be correct, fast and scalable, regardless of the scenario (i.e.,different workloads, processors, memory units, programming abstractions). Nevertheless, few or no generic approaches exist that result in concurrent data structures which scale in a large spectrum of environments. This dissertation introduces a set of generic methods that allows to build - irrespective of the deployment environment - fast and scalable concurrent data structures. We start by identifying a set of sufficient conditions for concurrent search data structures to scale and perform well regardless of the workloads and processors they are running on.We introduce âasynchronized concurrencyâ, a paradigm consisting of four complementary programming patterns, which calls for the design of concurrent search data structures to resemble that of their sequential counterparts. Next, we show that there is virtually no practical situation in which one should seek a âtheoretically wait-freeâ algorithm at the expense of a state-of-the-art blocking algorithm in the case of search data structures: blocking algorithms are simple, fast, and can be made "practically wait-free". We then focus on the memory unit, and provide a method yielding fast concurrent data structures even when the memory is non-volatile, and structures must be recoverable in case of a transient failure. We start by introducing a generic technique that allows us to avoid doing expensive writes to non-volatile memory by using a fast software cache. We also study memory management, and propose a solution tailored to concurrent data structures that uses coarse-grained memory management in order to avoid logging. Moreover, we argue for the use of lock-free algorithms in this non-volatile context, and show how by optimizing them we can avoid expensive logging operations. Together, the techniques we propose enable us to avoid any form of logging in the common case, thus significantly improving concurrent data structure performance when using non-volatile RAM. Finally, we go beyond basic interfaces, and look at scalable partitioned data structures implemented through a transactional interface. We present multiversion timestamp locking (MVTL),a new genre of multiversion concurrency control algorithms for serializable transactions. The key idea behind MVTL is simple and novel: lock individual time points instead of locking objects or versions. We provide several MVTL-based algorithms, that address limitations of current concurrency-control schemes. In short, by spanning workloads, processors, storage abstractions, and system sizes, this dissertation takes a step towards concurrent data structures that are universally scalable

    Designing ASCY-compliant Concurrent Search Data Structures

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    This report details the design of two new concurrent data structures, a hash table, called CLHT, and a binary search tree (BST), called BST-TK. Both designs are based on asynchronized concurrency (ASCY), a paradigm consisting of four complementary programming patterns. ASCY calls for the design of concurrent search data structures to resemble that of their sequential counterparts. CLHT (cache-line hash table) uses cache-line-sized buckets and performs in-place updates. As a cache-line block is the granularity of the cache-coherence protocols, CLHT ensures that most operations are completed with at most one cache-line transfer. BST-TK reduces the number of cache-line transfers by acquiring less locks than existing BSTs

    Particularităţi morfologice ale leziunilor pulmonare în tuberculoza multidrogrezistentă

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    În tuberculoza pulmonară multidrogrezistentă leziunile tuberculoase din materialul de rezecţie, sunt reprezentate preponderent în faza progresivă a procesului inflamator specific – persistenţa componentului exsudativ-necrotic în peretele cavernei, evoluare torpidă a resorbţiei şi organizării leziunilor necrocazeoase, ramolire cu distrucţie în focare, diseminare granulomatoasă şi tip necrotic pericavitar, perifocal şi în ţesutul pulmonar adiacent, afectarea infiltrativ-productivă a bronhiilor mici şi a bronhiolelor, nivel scăzut al reacţiei limfocitare în leziunile tuberculoase şi în ţesutul pulmonar adiacent

    Textile chemiresistors with sensitive layers based on polymer ionic liquids: applicability for detection of toxic gases and chemical warfare agents

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    The article presents pioneering research of textile chemiresistors on Evolon and Polyester substrates equipped with graphite electrodes and in-situ polymerized poly(tetrabutylphosphonium 3- sulfopropylacrylate) or poly(tributylhexyl- phosphonium 3-sulfopropylacrylate) sensitive layers. The DC- and AC- responses to 10 ppm of methanol, nitrogen dioxide, 4-bromoacetophenone, diethylmalonate and yperite were then investigated at laboratory temperature – the reference was "pure" synthetic air. Under these circumstances the DC- responses (SDC) varied from 0.48 to 1.36 and maximum AC- responses (Spa) from 8 to 26 deg. It was shown that sensor dynamics depends mainly on molecular weight of the analytes. Moreover, the magnitude of AC-responses correlated both qualitatively and quantitatively with the dipole moments of the analyzed molecules

    The Use of Fertilizers and Pesticides in Wheat Production in the Main European Countries

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    The aspects highlighted in this paper refer to the application of fertilizers and plant protection products to the wheat crop, and their impact on total production, competitiveness in export markets, price optimization as a result of increased harvest quality, and not least row, ensuring farmers’ incomes. The present analysis concerned the areas cultivated with wheat, and the productions achieved in relation to the quantities of fertilizers and protection products used in wheat cultivation, in Romania, Germany, Spain, France, Italy, Hungary, Poland and the UK. The analysis highlighted that, the average productions are influenced both by the technology used, by the fertilization and treatments applied, as well as by other synergistic factors that intervene in wheat crops. In countries such as Spain and Italy, the correlation between the amounts of N (nitrogen), P2O5 (phosphorus), K2O (potassium) and the average production of wheat is insignificant, but in Romania and Hungary, there is a strong, direct connection between the number of fertilizers used and the average wheat crop yield. In Romania and Hungary, there is a very significant connection, but the production link average with pesticides is negative, while in Germany, the correlation is direct and quite intense for all types of fertilizers used, while the use of pesticides has a lower influence on average wheat production. In this study, we also applied a multiple regression model; in which the dependent variable was the average yield of wheat per ha and the independent variables were the average quantity of pesticides and fertilizers used. We used the “t Stat” values for each coefficient to determine whether the coefficient is equal to zero; where a high value of “t Stat”, greater than 2; indicates the fact that the coefficient is significantly different from the value zero. The “p-value” for each coefficient indicates the probability that the coefficient has the value zero. A value below the significance level of 5% results in a coefficient significantly different from zero and with an impact on the dependent variable. The use of fertilizers on wheat crops has a synergistic effect as shown by the multiple linear regression analysis which demonstrated a strong direct relationship, particularly with the amount of N, K2O and P2O5 applied

    Museal Indoor Air Quality and Public Health: An Integrated Approach for Exhibits Preservation and Ensuring Human Health

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    The quality of the indoor microclimate in museums is a problem of great interest to the contemporary society, given that it is in close connection with the health and comfort of visitors and employees, as well as with the integrity of the exhibits. Taking into account the fact that museums are places that have a special role in the community’s life and therefore attract a very large number of visitors of all ages, a very important issue is to determine the degree of safety that the indoor microclimate presents. Thus, the quality of the indoor microclimate was investigated inside an iconic museum in Romania, dating back to the 19th century, because pollutants from external or internal sources of the building, generated secondary, often anthropogenic, as a tendency to defend/adapt to climate change (CC), contribute to both local and regional pollution, but also lead to challenges in identifying links between air quality (AQ) and and climate change (CC). The methodology used was based on monitoring the main parameters of the microclimate (temperature, relative humidity and CO2) over a period of between October 2020 and March 2021, 21 weeks, as well as on determining the microbiological contamination of the air and some indoor exhibits located in three different areas of the museum. At the same time, the study aims to identify cheap, easy to implement and non-invasive solutions for removing fungi identified on exhibits for long-term preservation and reducing the risk of various pathologies in humans following prolonged exposure. The results obtained show that the indoor microclimate in the old heritage building favours the development of fungi, which have a high degree of contamination of the air (over 800 CFU/m3) and of the exhibits, representing a potential risk for the health of the visitors and museum workers. Thus, six species of yeast and five different fungi genera were identified in the air, while on the exhibits were individualised six fungi genera, a species of yeast and a bacterium. The most viable solution for cleaning materials, prolonging their lifespan and reducing the risk of disease in humans was represented by the use of essential oils (EO). Three essential oils (lavender, mint and lemon) were applied on an exhibit with five different microorganism genera, and it was observed that they have the ability to inhibit the spores from moulds and bacteria, being a very good alternative to the usual chemical treatments that are used in the cultural heritage field

    Museal Indoor Air Quality and Public Health: An Integrated Approach for Exhibits Preservation and Ensuring Human Health

    No full text
    The quality of the indoor microclimate in museums is a problem of great interest to the contemporary society, given that it is in close connection with the health and comfort of visitors and employees, as well as with the integrity of the exhibits. Taking into account the fact that museums are places that have a special role in the community’s life and therefore attract a very large number of visitors of all ages, a very important issue is to determine the degree of safety that the indoor microclimate presents. Thus, the quality of the indoor microclimate was investigated inside an iconic museum in Romania, dating back to the 19th century, because pollutants from external or internal sources of the building, generated secondary, often anthropogenic, as a tendency to defend/adapt to climate change (CC), contribute to both local and regional pollution, but also lead to challenges in identifying links between air quality (AQ) and and climate change (CC). The methodology used was based on monitoring the main parameters of the microclimate (temperature, relative humidity and CO2) over a period of between October 2020 and March 2021, 21 weeks, as well as on determining the microbiological contamination of the air and some indoor exhibits located in three different areas of the museum. At the same time, the study aims to identify cheap, easy to implement and non-invasive solutions for removing fungi identified on exhibits for long-term preservation and reducing the risk of various pathologies in humans following prolonged exposure. The results obtained show that the indoor microclimate in the old heritage building favours the development of fungi, which have a high degree of contamination of the air (over 800 CFU/m3) and of the exhibits, representing a potential risk for the health of the visitors and museum workers. Thus, six species of yeast and five different fungi genera were identified in the air, while on the exhibits were individualised six fungi genera, a species of yeast and a bacterium. The most viable solution for cleaning materials, prolonging their lifespan and reducing the risk of disease in humans was represented by the use of essential oils (EO). Three essential oils (lavender, mint and lemon) were applied on an exhibit with five different microorganism genera, and it was observed that they have the ability to inhibit the spores from moulds and bacteria, being a very good alternative to the usual chemical treatments that are used in the cultural heritage field

    First-line nivolumab (NIVO) plus ipilimumab (IPI) plus two cycles of chemotherapy (chemo) versus chemo alone (4 cycles) in patients with advanced non-small cell lung cancer (NSCLC): Two-year update from CheckMate 9LA.

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    International audienceIn the randomized phase 3 CheckMate 9LA trial (NCT03215706), first-line NIVO + IPI combined with 2 cycles of chemo significantly improved overall survival (OS), progression-free survival (PFS), and objective response rate (ORR) vs chemo alone (4 cycles). Clinical benefit was observed regardless of programmed death ligand 1 (PD-L1) expression level and histology. Here we report data with 2 years’ minimum follow-up from this study. Methods: Adult patients (pts) with stage IV / recurrent NSCLC, ECOG performance status ≤ 1, and no known sensitizing EGFR/ALK alterations were stratified by PD-L1 (< 1% vs ≥ 1%), sex, and histology (squamous vs non-squamous) and were randomized 1:1 to NIVO 360 mg Q3W + IPI 1 mg/kg Q6W + chemo (2 cycles; n = 361) or chemo alone (4 cycles; n = 358). Pts with non-squamous NSCLC in the chemo-alone arm could receive pemetrexed maintenance. The primary endpoint was OS. Secondary endpoints included PFS and ORR by blinded independent central review, and efficacy by different PD-L1 levels. Safety was exploratory. Results: At a minimum follow-up of 24.4 months for OS (database lock: Feb 18, 2021), pts treated with NIVO + IPI + chemo continued to derive OS benefit vs chemo, with a median OS of 15.8 months vs 11.0 months, respectively (HR, 0.72 [95% CI, 0.61–0.86]); 2-year OS rates were 38% vs 26%. Median PFS with NIVO + IPI + chemo vs chemo was 6.7 months vs 5.3 months (HR, 0.67 [95% CI, 0.56–0.79]); 8% and 37% of pts who had disease progression received subsequent immunotherapy, respectively. ORR was 38% with NIVO + IPI + chemo vs 25% with chemo. Similar clinical benefit with NIVO + IPI + chemo vs chemo was observed in all randomized pts and across the majority of subgroups, including by PD-L1 expression level (Table) or histology. Any grade and grade 3–4 treatment-related adverse events were reported in 92% and 48% of pts in the NIVO + IPI + chemo arm vs 88% and 38% in the chemo arm, respectively. Conclusion: With 2 years’ minimum follow-up, first-line NIVO + IPI + chemo demonstrated durable survival and benefit versus chemo in pts with advanced NSCLC; no new safety signals were identified

    First-line nivolumab plus ipilimumab combined with two cycles of chemotherapy in patients with non-small-cell lung cancer (CheckMate 9LA): an international, randomised, open-label, phase 3 trial

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    Erratum in Correction to Lancet Oncol 2021; 22: 198-211. [No authors listed] Lancet Oncol. 2021 Mar;22(3):e92. doi: 10.1016/S1470-2045(21)00082-6. PMID: 33662299 No abstract available.International audienceBackground: First-line nivolumab plus ipilimumab has shown improved overall survival in patients with advanced non-small-cell lung cancer (NSCLC). We aimed to investigate whether the addition of a limited course (two cycles) of chemotherapy to this combination would further enhance the clinical benefit.Methods: This randomised, open-label, phase 3 trial was done at 103 hospitals in 19 countries. Eligible patients were aged 18 years or older with treatment-naive, histologically confirmed stage IV or recurrent NSCLC, and an Eastern Cooperative Oncology Group performance status of 0-1. Patients were randomly assigned (1:1) by an interactive web response system via permuted blocks (block size of four) to nivolumab (360 mg intravenously every 3 weeks) plus ipilimumab (1 mg/kg intravenously every 6 weeks) combined with histology-based, platinum doublet chemotherapy (intravenously every 3 weeks for two cycles; experimental group), or chemotherapy alone (every 3 weeks for four cycles; control group). Randomisation was stratified by tumour histology, sex, and PD-L1 expression. The primary endpoint was overall survival in all randomly assigned patients. Safety was analysed in all treated patients. Results reported here are from a pre-planned interim analysis (when the study met its primary endpoint) and an exploratory longer-term follow-up analysis. This study is active but no longer recruiting patients, and is registered with ClinicalTrials.gov, number NCT03215706.Findings: Between Aug 24, 2017, and Jan 30, 2019, 1150 patients were enrolled and 719 (62·5%) randomly assigned to nivolumab plus ipilimumab with two cycles of chemotherapy (n=361 [50%]) or four cycles of chemotherapy alone (n=358 [50%]). At the pre-planned interim analysis (median follow-up 9·7 months [IQR 6·4-12·8]), overall survival in all randomly assigned patients was significantly longer in the experimental group than in the control group (median 14·1 months [95% CI 13·2-16·2] vs 10·7 months [9·5-12·4]; hazard ratio [HR] 0·69 [96·71% CI 0·55-0·87]; p=0·00065). With 3·5 months longer median follow-up (median 13·2 months [IQR 6·4-17·0]), median overall survival was 15·6 months (95% CI 13·9-20·0) in the experimental group versus 10·9 months (9·5-12·6) in the control group (HR 0·66 [95% CI 0·55-0·80]). The most common grade 3-4 treatment-related adverse events were neutropenia (in 24 [7%] patients in the experimental group vs 32 [9%] in the control group), anaemia (21 [6%] vs 50 [14%]), diarrhoea (14 [4%] vs two [1%]), increased lipase (22 [6%] vs three [1%]), and asthenia (tjree [1%] vs eight [2%]). Serious treatment-related adverse events of any grade occurred in 106 (30%) patients in the experimental group and 62 (18%) in the control group. Seven (2%) deaths in the experimental group (acute kidney failure, diarrhoea, hepatotoxicity, hepatitis, pneumonitis, sepsis with acute renal insufficiency, and thrombocytopenia; one patient each) and six (2%) deaths in the control group (anaemia, febrile neutropenia, pancytopenia, pulmonary sepsis, respiratory failure, and sepsis; one patient each) were treatment related.Interpretation: Nivolumab plus ipilimumab with two cycles of chemotherapy provided a significant improvement in overall survival versus chemotherapy alone and had a favourable risk-benefit profile. These data support this regimen as a new first-line treatment option for patients with advanced NSCLC.Funding: Bristol Myers Squibb
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