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Efficient join processing is one of the most fundamental and well-studied tasks in database research. In this work, we examine algorithms for natural join queries over many relations and describe a new algorithm to process these queries optimally in terms of worst-case data complexity. Our result builds on recent work by Atserias, Grohe, and Marx, who gave bounds on the size of a natural join query in terms of the sizes of the individual relations in the body of the query. These bounds, however, are not constructive: they rely on Shearer’s entropy inequality, which is information-theoretic. Thus, the previous results leave open the question of whether there exist algorithms whose runtimes achieve these optimal bounds. An answer to this question may be interesting to database practice, as we show in this article that any project-join style plans, such as ones typically employed in a relational database management system, are asymptotically slower than the optimal for some queries. We present an algorithm whose runtime is worst-case optimal for all natural join queries. Our result may be of independent interest, as our algorithm also yields a constructive proof of the general fractional cover bound by Atserias, Grohe, and Marx without using Shearer’s inequality. This bound implies two famous inequalities in geometry: the Loomis-Whitney inequality and its generalization, the Bollobás-Thomason inequality. Hence, our results algorithmically prove these inequalities as well. Finally, we discuss how our algorithm can be used to evaluate full conjunctive queries optimally, to compute a relaxed notion of joins and to optimally (in the worst-case) enumerate all induced copies of a fixed subgraph inside of a given large graph. [ABSTRACT FROM AUTHOR]

Life cycle assessments in the construction industry reveal that 70–80% of all CO2 emissions occur precisely at the stage of material production (stages A1–A3 of the life cycle). Therefore, not only does the strength and thermal properties of the material selected for construction have major importance, but also the environmental impact of the material and the amount of energy spent to extract, manufacture and transport the materials. The paper presents the thermal calculations for envelope structures, assessing their environmental impact with respect to three parameters: carbon dioxide emissions, total energy consumption and amount of waste generated during material production. The research method used was an analysis of documents from real manufacturers and calculations of the main environmental parameters. Our investigation has led us to conclude that the largest amount of carbon dioxide emissions is produced by structures containing reinforced concrete, since the weight fraction of concrete is significantly greater than that of all other compared materials. The largest amount of non-renewable energy is consumed by structures containing clay bricks and reinforced concrete, since they consist of natural sources. The largest amount of waste is generated by structures containing expanded polystyrene and reinforced concrete consisting of cement, whose production in turn generates a large amount of waste. [ABSTRACT FROM AUTHOR]

Pancreatic hemorrhage is one of the most severe complications of various pancreatic diseases that are difficult to treat even in multidisciplinary hospitals. Mortality from pancreatic hemorrhage can reach up to 80%. This study aimed to evaluate the possibility of maintaining endovascular homeostasis in the treatment of patients with pancreatic hemorrhage. This retrospective multicenter study included 45 patients (33 men and 12 women) in the age range of 27-84 years. More than 50% (n=23) of the patients were diagnosed with chronic pancreatitis. Malignant pancreatic lesions were observed in 22 patients; of whom11 patients had acute necrotizing pancreatitis. Acute bleeding was observed in 39 (86.6%) patients, and 6 (13.3%) patients showed chronic symptoms. Single-shot and recurrent bleeding was recorded in 22(48.9%) and 23 (51.1%) patients. In total, 57 patients underwent endovascular surgery. Moreover, 45 patients underwent primary surgery and another 12 (2.2%) underwent reoperation due to recurrent bleeding. Intraoperative complications occurred in 1 (2.2%) patient, and postoperative complications occurred in another. Out of all 45 patients, seven patients had 15 episodes of recurrent bleeding, of whom four patients showed recurrent bleeding at the in-hospital period, and the other three were under local supervision after the previous endovascular intervention. Out of the 45 patients, 35 (77.7%) survived and another 10 (22.2%) died due to multiple organ failure (n=8) and recurrent bleeding and hemorrhagic shock (n=2). Out of 10 patients who died, 4, 3, and 3patients showed malignant pancreatic lesions after surgery, acute pancreatitis, and chronic pancreatitis, respectively. Endovascular hemostatic interventions can significantly increase the survival rate in severe groups of patients with pancreatic bleeding. Endovascular hemostasis is a safe procedure and may be called the “method of choice” in the treatment of pancreatic bleeding, especially in combination with percutaneous draining, aspiration, and injection of liquid embolic agents into leakage of pancreatic juice. [ABSTRACT FROM AUTHOR]

Purpose: Cystic fibrosis (CF) is one of the most common monogenic diseases with an autosomal recessive inheritance. Carrier screening leads to a reduction in the number of children born with CF disease. The aim of this study was to develop the custom panel for the diagnosis of heterozygous carriage of polymorphic variants in the CFTR gene and to establish their allelic frequencies (AF) in one of the Russian regions where ethnic Russians predominate. Patients and Methods: The diagnostic panel was designed on the basis of data from the register of CF patients in Russia for 2017 and validated on 22 blood samples of patients with previously genetically established CF. The study participants (n=642) for CF variants estimation were randomly selected from the population-based cohort study ESSE-Vologda. Genotypes were determined by real-time PCR on the QuantStudio 12K Flex Real-Time PCR System. Data processing was performed using the TaqMan Genotyper Software. Results: The proposed diagnostic panel allowed simultaneous analysis of 60 variants of the CFTR gene. A total of 23 carriers of the following variants were identified among 642 participants: F508del (rs113993960) with a frequency of 2.02%, L138ins (rs397508686) and 394delTT (rs121908769) – 0.47%, CFTRdele2.3 (c.54– 5940_273+10250del21080; p.S18Rfs*16) – 0.31%, R117H (rs78655421), and G542X (rs113993959) – 0.16%. The frequency of heterozygotes in the Russian population was 3.58% or 1:28 (CI95%: 2.28– 5.33% by Clopper–Pearson exact method). Conclusion: High frequency of heterozygous CFTR variants carriers and availability of highly productive diagnostic panel for detection of CFTR variants suggest the prospect of carrier screening for some common CF variants among Russian population. [ABSTRACT FROM AUTHOR]

Mg alloys containing long period stacking ordered (LPSO) structures possess excellent mechanical properties and corrosion resistance, exhibiting great application potential in biodegradable implants. The corrosion process of different LPSO phases in the Mg alloys need to be furtherly clarified in different solution environments. In this paper, we mainly reviewed the influencing factors on the corrosion behavior of LPSO-containing Mg alloys, including the alloying elements, processing technologies, and the types, volume fractions and distributions of LPSO phases. Recent researches are well summarized with an emphasis on their corrosion mechanism. Special attention is given to the key issues for LPSO-containing Mg alloys as biomedical implants, with their biodegradation behavior comprehensively discussed. The motivation is to provide theoretical support for the possible application of LPSO-containing Mg alloys in the biomedical field. [ABSTRACT FROM AUTHOR]

The subtle and unique imprint of dark matter substructure on extended arcs in strong-lensing systems contains a wealth of information about the properties and distribution of dark matter on small scales and, consequently, about the underlying particle physics. However, teasing out this effect poses a significant challenge since the likelihood function for realistic simulations of population-level parameters is intractable. We apply recently developed simulation-based inference techniques to the problem of substructure inference in galaxy–galaxy strong lenses. By leveraging additional information extracted from the simulator, neural networks are efficiently trained to estimate likelihood ratios associated with population-level parameters characterizing substructure. Through proof-of-principle application to simulated data, we show that these methods can provide an efficient and principled way to simultaneously analyze an ensemble of strong lenses and can be used to mine the large sample of lensing images deliverable by near-future surveys for signatures of dark matter substructure. We find that, within our simplified modeling framework, analyzing a sample of around 100 lenses can already pin down the overall abundance of substructure within lensing galaxies to a precision of % with greater sensitivity expected from a larger lens sample. (https://github.com/smsharma/StrongLensing-Inference) [ABSTRACT FROM AUTHOR]

We investigated the shortening or abolishing shift report as the effect of implementing electronic nursing and medical records and its side effects at 10 Japanese hospitals. The majority of staff nurses accepted this change, but both directors and staff nurses recognized the risk of insufficient collection and communication of patient information, difficulties of understanding the risks and matters of patients not under care and an increase in time to collect information from the computer before starting patient care. Directors should carefully evaluate and reduce the negative influences associated with changing or eliminating the traditional shift report. [ABSTRACT FROM AUTHOR]

Factors influencing the pyrolysis process of Longkou oil shale, such as nitrogen flow rate, pyrolysis temperature, particle size, and heating rate, were investigated in order to optimize the pyrolysis condition and reduce the secondary reactions. Oil yield reached the maximum value, 17.46 %, higher than Fischer assay oil yield, at heating rate 15 °C min up to 550 °C under 0.6 L min nitrogen flow rate for 2- to 3-mm oil shale particles. Compared with the retorting gas obtained from Fischer assay, the retorting gas under optimized condition had a higher organic/inorganic gas ratio and alkanes/alkenes (C1-C5), due to the inhibition of the gas cracking or secondary gas phase reactions. And the shale oil obtained from optimized condition had a lower IBP and higher distilled mass percent when reaching the same end temperature, 750 °C. The content of total alkanes and alkenes in the shale oil under optimized condition was 401 and 181 mg g, which were higher than those from Fischer assay, but the C8-C10 alkenes were lower, proving that optimizing pyrolysis condition was beneficial to reducing the secondary reactions. [ABSTRACT FROM AUTHOR]

A low computational cost method is proposed for detecting actuator/sensor faults. Typical model-based fault detection (FD) units for multiple sensor faults require a bank of estimators [i.e., conventional Kalman estimators or artificial intelligence (AI)-based ones]. The proposed FD scheme uses an AI approach for developing of a low computational power FD unit abbreviated as $i$ FD. In contrast to the bank-of-estimators approach, the proposed $i$ FD unit employs a single estimator for multiple actuator/sensor FD. The efficacy of the proposed FD scheme is illustrated through a rigorous analysis of the results for a number of sensor fault scenarios on an electromagnetic suspension system. [ABSTRACT FROM PUBLISHER]

A new synthesis of the catechol- O-methyltransferase (COMT) inhibitor, entacapone (E-isomer) has been achieved under mild conditions by amine-mediated demethylation of the precursor 2-Cyano-3-(3- hydroxy-4-methoxy-5-nitrophenyl) prop-2-eneamide, wherein the methoxyl group adjacent to a nitro group gets demethylated under nucleophilic attack. Similar demethylation was achieved on ethyl 2-cyano-3-(3, 4-dimethoxy-5-nitrophenyl) prop-2-enoate, 2-cyano-3-(3,4-dimethoxy-5-nitrophenyl)-N,N-diethylprop-2-enamide, ethyl 2-cyano-3-(3-hydroxy-4-methoxy-5-nitrophenyl) prop-2-enoate and ethyl 2-cyano-3-(4-methoxy-3-nitrophenyl) prop-2-enoate. The scope of demethylation has been studied. Analogues of ethyl 2-cyano-3-(3, 4-dimethoxy-5-nitrophenyl) prop-2-enoate wherein a methoxyl group is not adjacent to a NO group are unaffected and phenolic derivatives yield the amine salts. Entacapone has been converted to salts with organic bases. The crystal structure of the isomer of entacapone (Z-isomer), a significant human metabolite of E-isomer has been established. NMR methods for deriving E and Z geometry and other similar molecules have been successfully established, mainly by studying the proton coupled C spectra. Preliminary studies reveal in vitro activity for some compounds against tuberculosis (TB) and dengue. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Background: Cystic fibrosis (CF) is one of the most common life-threatening genetic disorders. Around 2000 variants in the CFTR gene have been identified, with some proportion known to be pathogenic and 300 disease-causing mutations have been characterized in detail by CFTR2 database, which complicates its analysis with conventional methods. Methods: We conducted next-generation sequencing (NGS) in a cohort of 89 adult patients negative for p.Phe508del homozygosity. Complete clinical and demographic information were available for 84 patients. Results: By combining MLPA with NGS, we identified disease-causing alleles in all the CF patients. Importantly, in 10% of cases, standard bioinformatics pipelines were inefficient in identifying causative mutations. Class IV-V mutations were observed in 38 (45%) cases, predominantly ones with pancreatic sufficient CF disease; rest of the patients had Class I-III mutations. Diabetes was seen only in patients homozygous for class I-III mutations. We found that 12% of the patients were heterozygous for more than two pathogenic CFTR mutations. Two patients were observed with p.[Arg1070Gln, Ser466*] complex allele which was associated with milder pulmonary obstructions (FVC 107 and 109% versus 67%, CI 95%: 63-72%; FEV 90 and 111% versus 47%, CI 95%: 37-48%). For the first time p.[Phe508del, Leu467Phe] complex allele was reported, observed in four patients (5%). Conclusion: NGS can be a more information-gaining technology compared to standard methods. Combined with its equivalent diagnostic performance, it can therefore be implemented in the clinical practice, although careful validation is still required. [ABSTRACT FROM AUTHOR]