307 research outputs found

    LLM4PLC: Harnessing Large Language Models for Verifiable Programming of PLCs in Industrial Control Systems

    Full text link
    Although Large Language Models (LLMs) have established pre-dominance in automated code generation, they are not devoid of shortcomings. The pertinent issues primarily relate to the absence of execution guarantees for generated code, a lack of explainability, and suboptimal support for essential but niche programming languages. State-of-the-art LLMs such as GPT-4 and LLaMa2 fail to produce valid programs for Industrial Control Systems (ICS) operated by Programmable Logic Controllers (PLCs). We propose LLM4PLC, a user-guided iterative pipeline leveraging user feedback and external verification tools including grammar checkers, compilers and SMV verifiers to guide the LLM's generation. We further enhance the generation potential of LLM by employing Prompt Engineering and model fine-tuning through the creation and usage of LoRAs. We validate this system using a FischerTechnik Manufacturing TestBed (MFTB), illustrating how LLMs can evolve from generating structurally flawed code to producing verifiably correct programs for industrial applications. We run a complete test suite on GPT-3.5, GPT-4, Code Llama-7B, a fine-tuned Code Llama-7B model, Code Llama-34B, and a fine-tuned Code Llama-34B model. The proposed pipeline improved the generation success rate from 47% to 72%, and the Survey-of-Experts code quality from 2.25/10 to 7.75/10. To promote open research, we share the complete experimental setup, the LLM Fine-Tuning Weights, and the video demonstrations of the different programs on our dedicated webpage.Comment: 12 pages; 8 figures; Appearing in the 46th International Conference on Software Engineering: Software Engineering in Practice; for demo website, see https://sites.google.com/uci.edu/llm4plc/hom

    A general class of arbitrary order iterative methods for computing generalized inverses

    Full text link
    [EN] A family of iterative schemes for approximating the inverse and generalized inverse of a complex matrix is designed, having arbitrary order of convergence p. For each p, a class of iterative schemes appears, for which we analyze those elements able to converge with very far initial estimations. This class generalizes many known iterative methods which are obtained for particular values of the parameters. The order of convergence is stated in each case, depending on the first non-zero parameter. For different examples, the accessibility of some schemes, that is, the set of initial estimations leading to convergence, is analyzed in order to select those with wider sets. This wideness is related with the value of the first non-zero value of the parameters defining the method. Later on, some numerical examples (academic and also from signal processing) are provided to confirm the theoretical results and to show the feasibility and effectiveness of the new methods. (C) 2021 The Authors. Published by Elsevier Inc.This research was supported in part by PGC2018-095896-B-C22 (MCIU/AEI/FEDER, UE) and in part by VIE from Instituto Tecnologico de Costa Rica (Research #1440037)Cordero Barbero, A.; Soto-Quiros, P.; Torregrosa SĂĄnchez, JR. (2021). A general class of arbitrary order iterative methods for computing generalized inverses. Applied Mathematics and Computation. 409:1-18. https://doi.org/10.1016/j.amc.2021.126381S11840

    Combinations of ÎČ-lactam or aminoglycoside antibiotics with plectasin are synergistic against methicillin-sensitive and methicillin-resistant Staphylococcus aureus.

    Get PDF
    Bacterial infections remain the leading killer worldwide which is worsened by the continuous emergence of antibiotic resistance. In particular, methicillin-sensitive (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) are prevalent and the latter can be difficult to treat. The traditional strategy of novel therapeutic drug development inevitably leads to emergence of resistant strains, rendering the new drugs ineffective. Therefore, rejuvenating the therapeutic potentials of existing antibiotics offers an attractive novel strategy. Plectasin, a defensin antimicrobial peptide, potentiates the activities of other antibiotics such as ÎČ-lactams, aminoglycosides and glycopeptides against MSSA and MRSA. We performed in vitro and in vivo investigations to test against genetically diverse clinical isolates of MSSA (n = 101) and MRSA (n = 115). Minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. The effects of combining plectasin with ÎČ-lactams, aminoglycosides and glycopeptides were examined using the chequerboard method and time kill curves. A murine neutropenic thigh model and a murine peritoneal infection model were used to test the effect of combination in vivo. Determined by factional inhibitory concentration index (FICI), plectasin in combination with aminoglycosides (gentamicin, neomycin or amikacin) displayed synergistic effects in 76-78% of MSSA and MRSA. A similar synergistic response was observed when plectasin was combined with ÎČ-lactams (penicillin, amoxicillin or flucloxacillin) in 87-89% of MSSA and MRSA. Interestingly, no such interaction was observed when plectasin was paired with vancomycin. Time kill analysis also demonstrated significant synergistic activities when plectasin was combined with amoxicillin, gentamicin or neomycin. In the murine models, plectasin at doses as low as 8 mg/kg augmented the activities of amoxicillin and gentamicin in successful treatment of MSSA and MRSA infections. We demonstrated that plectasin strongly rejuvenates the therapeutic potencies of existing antibiotics in vitro and in vivo. This is a novel strategy that can have major clinical implications in our fight against bacterial infections

    ĐœĐ”Ń‚ĐŸĐŽĐŸĐ»ĐŸĐłŃ–Ń ĐČŃ–Ń‚Ń‡ĐžĐ·ĐœŃĐœĐŸŃ— ĐșŃ€ĐžĐŒŃ–ĐœĐ°Đ»ŃŒĐœĐŸ-праĐČĐŸĐČĐŸŃ— ĐœĐ°ŃƒĐșĐž: ŃŃ‚Đ°ĐœĐŸĐČĐ»Đ”ĐœĐœŃ Ń–ŃŃ‚ĐŸŃ€ĐžŃ‡ĐœĐŸĐłĐŸ ĐŒĐ”Ń‚ĐŸĐŽŃƒ та ĐżŃ€ĐŸĐ±Đ»Đ”ĐŒĐž ĐœĐ°ŃŃ‚ŃƒĐżĐœĐŸŃŃ‚Ń–

    Get PDF
    ĐĐœĐ°Đ»Ń–Đ·ŃƒŃŽŃ‚ŃŒŃŃ ĐŒĐ”Ń‚ĐŸĐŽĐŸĐ»ĐŸĐłŃ–Ń‡ĐœŃ– ĐżŃ€ĐŸĐ±Đ»Đ”ĐŒĐž ĐșŃ€ĐžĐŒŃ–ĐœĐ°Đ»ŃŒĐœĐŸ-праĐČĐŸĐČĐŸŃ— ĐœĐ°ŃƒĐșĐž, Đ·ĐŸĐșŃ€Đ”ĐŒĐ° ĐżŃ€ĐŸŃ†Đ”Ń ŃŃ‚Đ°ĐœĐŸĐČĐ»Đ”ĐœĐœŃ Ń–ŃŃ‚ĐŸŃ€ĐžŃ‡ĐœĐŸĐłĐŸ ĐŒĐ”Ń‚ĐŸĐŽŃƒ та ĐčĐŸĐłĐŸ Ń€ĐŸĐ»Ń– у ĐČĐžĐČŃ‡Đ”ĐœĐœŃ– ĐżĐžŃ‚Đ°ĐœŃŒ ĐœĐ°ŃŃ‚ŃƒĐżĐœĐŸŃŃ‚Ń– ĐČ ĐșŃ€ĐžĐŒŃ–ĐœĐ°Đ»ŃŒĐœĐŸĐŒŃƒ праĐČі.ĐĐœĐ°Đ»ĐžĐ·ĐžŃ€ŃƒŃŽŃ‚ŃŃ ĐŒĐ”Ń‚ĐŸĐŽĐŸĐ»ĐŸĐłĐžŃ‡Đ”ŃĐșОД ĐżŃ€ĐŸĐ±Đ»Đ”ĐŒŃ‹ ŃƒĐłĐŸĐ»ĐŸĐČĐœĐŸ-праĐČĐŸĐČĐŸĐč ĐœĐ°ŃƒĐșĐž, ĐČ Ń‡Đ°ŃŃ‚ĐœĐŸŃŃ‚Đž ĐżŃ€ĐŸŃ†Đ”ŃŃ ŃŃ‚Đ°ĐœĐŸĐČĐ»Đ”ĐœĐžŃ ĐžŃŃ‚ĐŸŃ€ĐžŃ‡Đ”ŃĐșĐŸĐłĐŸ ĐŒĐ”Ń‚ĐŸĐŽĐ° Đž Đ”ĐłĐŸ Ń€ĐŸĐ»Đž ĐČ ĐžĐ·ŃƒŃ‡Đ”ĐœĐžĐž ĐČĐŸĐżŃ€ĐŸŃĐŸĐČ ĐżŃ€Đ”Đ”ĐŒŃŃ‚ĐČĐ”ĐœĐœĐŸŃŃ‚Đž ĐČ ŃƒĐłĐŸĐ»ĐŸĐČĐœĐŸĐŒ праĐČĐ”.The paper is devoted to an analysis of methodological problems of a criminal legal sci­ence, namely, an establishing process of historical method and its role in studying succession issues in a criminal law

    Core components for effective infection prevention and control programmes: new WHO evidence-based recommendations

    Get PDF
    Abstract Health care-associated infections (HAI) are a major public health problem with a significant impact on morbidity, mortality and quality of life. They represent also an important economic burden to health systems worldwide. However, a large proportion of HAI are preventable through effective infection prevention and control (IPC) measures. Improvements in IPC at the national and facility level are critical for the successful containment of antimicrobial resistance and the prevention of HAI, including outbreaks of highly transmissible diseases through high quality care within the context of universal health coverage. Given the limited availability of IPC evidence-based guidance and standards, the World Health Organization (WHO) decided to prioritize the development of global recommendations on the core components of effective IPC programmes both at the national and acute health care facility level, based on systematic literature reviews and expert consensus. The aim of the guideline development process was to identify the evidence and evaluate its quality, consider patient values and preferences, resource implications, and the feasibility and acceptability of the recommendations. As a result, 11 recommendations and three good practice statements are presented here, including a summary of the supporting evidence, and form the substance of a new WHO IPC guideline

    Asthma-susceptibility variants identified using probands in case-control and family-based analyses

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Asthma is a chronic respiratory disease whose genetic basis has been explored for over two decades, most recently via genome-wide association studies. We sought to find asthma-susceptibility variants by using probands from a single population in both family-based and case-control association designs.</p> <p>Methods</p> <p>We used probands from the Childhood Asthma Management Program (CAMP) in two primary genome-wide association study designs: (1) probands were combined with publicly available population controls in a case-control design, and (2) probands and their parents were used in a family-based design. We followed a two-stage replication process utilizing three independent populations to validate our primary findings.</p> <p>Results</p> <p>We found that single nucleotide polymorphisms with similar case-control and family-based association results were more likely to replicate in the independent populations, than those with the smallest p-values in either the case-control or family-based design alone. The single nucleotide polymorphism that showed the strongest evidence for association to asthma was rs17572584, which replicated in 2/3 independent populations with an overall p-value among replication populations of 3.5E-05. This variant is near a gene that encodes an enzyme that has been implicated to act coordinately with modulators of Th2 cell differentiation and is expressed in human lung.</p> <p>Conclusions</p> <p>Our results suggest that using probands from family-based studies in case-control designs, and combining results of both family-based and case-control approaches, may be a way to augment our ability to find SNPs associated with asthma and other complex diseases.</p

    Elevated Expression of Stromal Palladin Predicts Poor Clinical Outcome in Renal Cell Carcinoma

    Get PDF
    The role that stromal renal cell carcinoma (RCC) plays in support of tumor progression is unclear. Here we sought to determine the predictive value on patient survival of several markers of stromal activation and the feasibility of a fibroblast-derived extracellular matrix (ECM) based three-dimensional (3D) culture stemming from clinical specimens to recapitulate stromal behavior in vitro. The clinical relevance of selected stromal markers was assessed using a well annotated tumor microarray where stromal-marker levels of expression were evaluated and compared to patient outcomes. Also, an in vitro 3D system derived from fibroblasts harvested from patient matched normal kidney, primary RCC and metastatic tumors was employed to evaluate levels and localizations of known stromal markers such as the actin binding proteins palladin, alpha-smooth muscle actin (α-SMA), fibronectin and its spliced form EDA. Results suggested that RCCs exhibiting high levels of stromal palladin correlate with a poor prognosis, as demonstrated by overall survival time. Conversely, cases of RCCs where stroma presents low levels of palladin expression indicate increased survival times and, hence, better outcomes. Fibroblast-derived 3D cultures, which facilitate the categorization of stromal RCCs into discrete progressive stromal stages, also show increased levels of expression and stress fiber localization of α-SMA and palladin, as well as topographical organization of fibronectin and its splice variant EDA. These observations are concordant with expression levels of these markers in vivo. The study proposes that palladin constitutes a useful marker of poor prognosis in non-metastatic RCCs, while in vitro 3D cultures accurately represent the specific patient's tumor-associated stromal compartment. Our observations support the belief that stromal palladin assessments have clinical relevance thus validating the use of these 3D cultures to study both progressive RCC-associated stroma and stroma-dependent mechanisms affecting tumorigenesis. The clinical value of assessing RCC stromal activation merits further study

    Atopic dermatitis and indoor use of energy sources in cooking and heating appliances

    Get PDF
    Background: Atopic dermatitis (AD) prevalence has considerably increased worldwide in recent years. Studying indoor environments is particularly relevant, especially in industrialised countries where many people spend 80% of their time at home, particularly children. This study is aimed to identify the potential association between AD and the energy source (biomass, gas and electricity) used for cooking and domestic heating in a Spanish schoolchildren population. Methods: As part of the ISAAC (International Study of Asthma and Allergies in Childhood) phase III study, a cross-sectional population-based survey was conducted with 21,355 6-to-7-year-old children from 8 Spanish ISAAC centres. AD prevalence, environmental risk factors and the use of domestic heating/cooking devices were assessed using the validated ISAAC questionnaire. Crude and adjusted odds ratios (cOR, aOR) and 95% confidence intervals (CIs) were obtained. A logistic regression analysis was performed (Chi-square test, p-value < 0.05). Results: It was found that the use of biomass systems gave the highest cORs, but only electric cookers showed a significant cOR of 1.14 (95% CI: 1.01-1.27). When the geographical area and the mother’s educational level were included in the logistic model, the obtained aOR values differed moderately from the initial cORs. Electric heating was the only type which obtained a significant aOR (1.13; 95% CI: 1.00-1.27). Finally, the model with all selected confounding variables (sex, BMI, number of siblings, mother’s educational level, smoking habits of parents, truck traffic and geographical area), showed aOR values which were very similar to those obtained in the previous adjusted logistic analysis. None of the results was statistically significant, but the use of electric heating showed an aOR close to significance (1.14; 95% CI: 0.99-1.31). Conclusion: In our study population, no statistically significant associations were found between the type of indoor energy sources used and the presence of AD

    Inborn errors of type I IFN immunity in patients with life-threatening COVID-19.

    Get PDF
    Clinical outcome upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ranges from silent infection to lethal coronavirus disease 2019 (COVID-19). We have found an enrichment in rare variants predicted to be loss-of-function (LOF) at the 13 human loci known to govern Toll-like receptor 3 (TLR3)- and interferon regulatory factor 7 (IRF7)-dependent type I interferon (IFN) immunity to influenza virus in 659 patients with life-threatening COVID-19 pneumonia relative to 534 subjects with asymptomatic or benign infection. By testing these and other rare variants at these 13 loci, we experimentally defined LOF variants underlying autosomal-recessive or autosomal-dominant deficiencies in 23 patients (3.5%) 17 to 77 years of age. We show that human fibroblasts with mutations affecting this circuit are vulnerable to SARS-CoV-2. Inborn errors of TLR3- and IRF7-dependent type I IFN immunity can underlie life-threatening COVID-19 pneumonia in patients with no prior severe infection
    • 

    corecore