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Enhancing oil recovery in reservoirs with light oil and high gas content relies on optimizing the miscible water alternating gas (WAG) injection profile. However, this can be costly and time-consuming due to computationally demanding compositional simulation models and numerous other well control variables. This study introduces WAGeq, a novel approach that expedites the convergence of the optimization algorithm for miscible water alternating gas (WAG) injection in carbonate reservoirs. The WAGeqleverages production data to create flexible solutions that maximize the net present value (NPV) of the field, while providing practical implementation of individual WAG profiles for each injector. The WAGequtilizes an injection priority index to rank the wells and determine which should inject water or gas at each time interval. The index is built using a parametric equation that considers factors such as producer and injector relationship, water cut (WCUT), gas–oil ratio (GOR), and wells cumulative gas production, to induce desirable effects on production and WAG profile. To evaluate WAGeq’s effectiveness, two other approaches were compared: a benchmark solution named WAGbm, in which the injected fluid is optimized for each well over time, and a traditional baseline strategy with fixed 6-month WAG cycles. The procedures were applied to a synthetic simulation case (SEC1_2022) with characteristics of a Brazilian pre-salt carbonate field with karstic formations and high CO2content. The WAGeqoutperformed the baseline procedure, improving the NPV by 6.7% or 511 USD million. Moreover, WAGeqrequired fewer simulations (less than 350) than WAGbm(up to 2000), while delivering a slightly higher NPV. The terms of the equation were also found to be essential for producing a WAG profile with regular patterns on each injector, resulting in a more practical solution. In conclusion, WAGeqsignificantly reduces computational requirements while creating consistent patterns across injectors, which are crucial factors to consider when planning a practical WAG strategy.

Co-registration is required when the alignment of two or more point clouds obtained for mapping natural and built environments is needed. While closed-form solutions are suitable for co-registration, most of the existing approaches rely on unit quaternion solutions for the estimation of transformation parameters from point or plane correspondences. This paper presents a novel co-registration of terrestrial light detection and ranging point clouds solution to create globally consistent 3-D environments. Our method exploits the advantages of the dual quaternion solution combining both points and plane correspondences. The role of our relaxation labeling technique in 3-D matching (3PRL) is investigated, and its efficiency to find the best plane correspondences is shown. The paper also presents a method to treat degenerate plane configurations with corresponding virtual points. Experimental results reveal that our 3PRL technique can update and improve the 3-D matching probabilities using binary relations. At the same time, the proposed dual quaternions point- and plane-based optimization indicated that the mathematical optimization might represent a valid model for co-registration of point clouds. A closer inspection of co-registration accuracy revealed that the translation and rotation error mean decreased drastically, with margins between 0.10 m and 0.17 m and 0.01° and 0.33°, respectively. Experiments have shown that our method generally achieves better results than existing methods.

Healthcare delivery organizations such as hospitals are complex infrastructures comprising a broad range of networked devices. They include connected medical devices which can deliver health care, support hospitals’ operations, and can exchange patients’ data over healthcare network protocols. Previous research has pointed out weaknesses in the implementations of some of these protocols, and demonstrated how they could be abused by malicious actors in hospitals. There are still other healthcare network protocols for which we have limited knowledge, and no security analysis can be found in the literature. This can represent an issue, as these technologies may also have vulnerabilities which could, if exploited, impact hospitals’ operations and patients’ data. For this reason, we investigate in this paper three healthcare protocols found in hospital networks: the POCT1-Aand LIS02-Astandards used by some point-of-care and laboratory devices, and the proprietary protocol Data Exportused by some Philips patient monitors. We explain how to build a test lab to perform security research on medical devices, in which we demonstrate four attacks highlighting how the selected protocols can be abused. This research provides greater knowledge of threats relevant to healthcare delivery organizations, and helps to enhance network security monitoring capabilities such as intrusion detection systems. More specifically, signatures can be created to detect attacks on these protocols and datasets can be assembled to assist the development and testing of hospital-specific intrusion detection systems.

Purpose: The radiologists’ workload is increasing, and computational imaging techniques may have the potential to identify visually unequivocal lesions, so that the radiologist can focus on equivocal and critical cases. The purpose of this study was to assess radiomics versus dual-energy CT (DECT) material decomposition to objectively distinguish visually unequivocal abdominal lymphoma and benign lymph nodes. Methods: Retrospectively, 72 patients [m, 47; age, 63.5 (27–87) years] with nodal lymphoma (n= 27) or benign abdominal lymph nodes (n= 45) who had contrast-enhanced abdominal DECT between 06/2015 and 07/2019 were included. Three lymph nodes per patient were manually segmented to extract radiomics features and DECT material decomposition values. We used intra-class correlation analysis, Pearson correlation and LASSO to stratify a robust and non-redundant feature subset. Independent train and test data were applied on a pool of four machine learning models. Performance and permutation-based feature importance was assessed to increase the interpretability and allow for comparison of the models. Top performing models were compared by the DeLong test. Results: About 38% (19/50) and 36% (8/22) of the train and test set patients had abdominal lymphoma. Clearer entity clusters were seen in t-SNE plots using a combination of DECT and radiomics features compared to DECT features only. Top model performances of AUC = 0.763 (CI = 0.435–0.923) were achieved for the DECT cohort and AUC = 1.000 (CI = 1.000–1.000) for the radiomics feature cohort to stratify visually unequivocal lymphomatous lymph nodes. The performance of the radiomics model was significantly (p= 0.011, DeLong) superior to the DECT model. Conclusions: Radiomics may have the potential to objectively stratify visually unequivocal nodal lymphoma versus benign lymph nodes. Radiomics seems superior to spectral DECT material decomposition in this use case. Therefore, artificial intelligence methodologies may not be restricted to centers with DECT equipment.

The research article was carried out with the objective of studying the genetic variation on the resilience of buffaloes to negative energy balance—NEB (measured by changes in body weight in early lactation)—as well as investigating genomic regions of interest for this trait. A model of reaction norms was used, considering milk production as the trait to be analyzed and solutions of the contemporary groups to weight changes as environmental gradient. In this methodology, the genetic value of the slope represents the measure of resilience of the animals. After the estimation step, a genome-wide association analysis was performed for the slope of the reaction norms model, to obtain a list of windows and associated genes. The heritability estimates for milk production over the resilience gradient ranged from 0.13 to 0.28, with lower values in the intermediate environmental groups. Regarding the productive resilience of dairy buffalo cows to NEB, the genomic windows with the highest contribution to the genetic variance were detected on chromosomes BBU 1, 2, 3, 4, 9, 12, 19, and 21. A functional analysis of the genes described in the selected windows indicated association with metabolic routes related to growth and immunity of the animals, with an emphasis on the STAT6 gene. The results presented indicate that there is for this trait genetic variation to be used as selection criteria, in addition to genomic regions that can increase the precision of the selection.

Clinically evident portal hypertension (CEPH) was previously identified as a prognostic factor for patients with hepatocellular carcinoma (HCC). However, little is known about the prognostic influence of CEPH on the long‐term outcome of patients with HCC undergoing transarterial chemoembolization (TACE), particularly in Western populations. This study investigated the prevalence and prognostic influence of CEPH in a Western population of patients with HCC undergoing TACE. This retrospective study included 349 treatment‐naïve patients that received initial TACE treatment at our tertiary care center between January 2010 and November 2020. CEPH was defined as a combination of ascites, esophageal/gastric varices, splenomegaly and a low platelet count. We assessed the influence of CEPH and its defining factors on median overall survival (OS) in HCC patients. We compared the effects of CEPH to those of well‐known prognostic factors. Of the 349 patients included, 304 (87.1%) patients had liver cirrhosis. CEPH was present in 241 (69.1%) patients. The median OS times were 10.6 months for patients with CEPH and 17.1 months for patients without CEPH (log rank p= 0.036). Median OS without a present surrogate was 17.1 months, while patients with one respectively more than two present CEPH surrogates had a median OS of 10.8 and 9.4 months (log rank p= 0.053). In multivariate analysis, CEPH was no significant risk factor for OS (p= 0.190). Of the CEPH‐defining factors, only ascites reached significance in a univariate analysis. CEPH was present in more than two thirds of the patients with HCC undergoing TACE in our cohort of Western patients. Patients with CEPH had a significantly impaired survival in univariate analysis. However, no significance was reached in multivariate analysis. Thus, when TACE treatment is deemed oncologically reasonable, patients should not be excluded from TACE treatment due to the presence of surrogates of portal hypertension alone.

Purpose: This paper aims to explore the changes imposed by the general data protection regulation (GDPR) on software engineering practices. The fundamental objective is to have a perception of the practices and phases that have experienced the greatest changes. Additionally, it aims to identify a set of good practices that can be adopted by software engineering companies. Design/methodology/approach: This study uses a qualitative methodology through four case studies involving Portuguese software engineering companies. Two of these companies are small and medium enterprises (SMEs) while the other remaining two are micro-companies. The thematic analysis is adopted to identify patterns in the performed interviews. Findings: The findings indicate that significant changes have occurred at all stages of software development. In particular, the initial stages of identifying requirements and modeling processes were the stages that experienced the greatest changes. On the opposite, the technical development phase has not noticeably changed but, nevertheless, it is necessary to look at the importance of training software developers for GDPR rules and practices. Research limitations/implications: Two relevant limitations were identified as follows: only four case studies involving micro-companies and SMEs were considered, and only the traditional software development methodology was considered. The use of agile methodologies was not explored in this study and the findings can only be mainly applied to the waterfall model. Originality/value: This study offers mainly practical contributions by identifying a set of challenges that are posed to software engineering companies by the implementation of GDPR. Through their knowledge, it is expected to help these companies to better prepare themselves and anticipate the challenges they will necessarily face.

Hintergrund: Der Hype um künstliche Intelligenz (KI) in der Radiologie ist ungebrochen, und die Anzahl an zugelassenen KI-Tools wächst stetig. Trotz des großen Potenzials bleibt die Integration in die radiologische Routine aktuell limitiert. Zudem bildet die Vielzahl an Einzelanwendungen eine Herausforderung für die klinische Routine, da für verschiedene Fragestellungen und Organsysteme einzelne Anwendungen angewählt werden müssen, was die Komplexität und den Zeitaufwand erhöht. Ziel der Arbeit: In dieser Übersichtsarbeit soll der aktuelle Stand der Validierung und Implementierung von KI-Tools in die klinische Routine mit den aktuellen Limitationen aufgezeigt werden. Außerdem sollen mögliche Lösungsansätze für eine verbesserte Evaluation der Generalisierbarkeit von Ergebnissen der KI-Tools diskutiert werden. Material und Methoden: Für diese Übersichtsarbeit wurde eine Recherche in verschiedenen Literatur- und Produktdatenbanken sowie in Veröffentlichungen, Positionspapieren und Berichten von verschiedenen Interessensgruppen durchgeführt. Ergebnisse: Für nur wenige kommerzielle KI-Tools sind wissenschaftliche Evidenz und unabhängige Validierungsstudien vorhanden. Zudem bleibt häufig die Generalisierbarkeit der Ergebnisse fraglich. Diskussion: Ein Problem besteht in der Vielzahl an Angeboten für einzelne, spezifische Anwendungsgebiete durch eine Vielzahl an Herstellern und die dadurch erschwerte Integration in die bestehende standortindividuelle IT-Infrastruktur. Ein weiteres Problem ist die fehlende wirtschaftliche Vergütung für den Einsatz von KI-Tools in der klinischen Routine durch die Krankenkassen in Deutschland. Für eine Vergütung muss jedoch zunächst der klinische Nutzen neuer Anwendungen nachgewiesen werden. Ein solcher Nachweis wiederum fehlt für die meisten Applikationen.

ABSTRACTIn this study, we evaluated the chemical composition and the in vitroanthelmintic efficacy of the essential oils (EOs) of the plants Aloysia triphylla, Adenocalymna alliaceum, Allium sativum, Croton cajucara(white and red morphotypes), Curcuma longa, Lippia gracilis, Lippia origanoides, Ocimum gratissimum, Mentha arvensis, and Piper aduncumagainst the Acantocephalan Neoechinorhynchus buttnerae. The in vitroviability of worms was observed after 24 h-exposure to nine concentrations of EOs from each plant. Lower EC50values were obtained for M. arvensis, L. origanoides, L. gracilis, C. cajucara(red and white morphotypes), O. gratissimum, and P. aduncum. All EOs showed 100% anthelmintic efficacy in vitroin 24 h. In regard to damage to the integument of helminths, edema in the lacunar spaces with formation of bubbles in the subcuticle, body swelling, increased volume of the pseudocelomatic cavity and degeneration of the reproductive organs were observed after exposure to A. triphyllaOE.

There is strong evidence that portal vein tumor thrombosis (PVTT) is associated with poor survival in patients with hepatocellular carcinoma (HCC). However, data regarding the clinical significance of hepatic vein tumor thrombosis (HVTT) is rare, particularly in Western patients. To determine the HVTT prevalence in a Western patient population and its impact on survival. We included 1310 patients with HCC treated in our tertiary referral center between January 2005 and December 2016. HVTT and PVTT were diagnosed with contrast‐enhanced cross‐sectional imaging. Overall survival (OS) was calculated starting from the initial HCC diagnosis, and in a second step, starting from the first appearance of vascular invasion. We observed macrovascular invasion (MVI) in 519 patients who suffered from either isolated HVTT (n= 40), isolated PVTT (n= 352), or both combined (HVTT + PVTT) (n= 127). Calculated from the initial HCC diagnosis, the median OS for patients with isolated HVTT was significantly shorter than that of patients without MVI (13.3 vs. 32.5 months, p< 0.001). Calculated from the first appearance of MVI, the median OS was similar among patients with isolated HVTT (6.5 months), isolated PVTT (5 months), and HVTT + PVTT (5 months). Multivariate analysis confirmed HVTT as an independent risk factor for poor survival. HVTT may be more common than typically reported. In most patients, it was accompanied by PVTT. Isolated HVTT occurred less frequently and later than isolated PVTT; however, once developed, it had the same deleterious impact on survival. Therefore, patients with HVTT should be classified as advanced stage of HCC.

Background: The advent of next-generation computed tomography (CT)- and magnetic resonance imaging (MRI) opened many new perspectives in the evaluation of tumor characteristics. An increasing body of evidence suggests the incorporation of quantitative imaging biomarkers into clinical decision-making to provide mineable tissue information. The present study sought to evaluate the diagnostic and predictive value of a multiparametric approach involving radiomics texture analysis, dual-energy CT-derived iodine concentration (DECT-IC), and diffusion-weighted MRI (DWI) in participants with histologically proven pancreatic cancer. Methods: In this study, a total of 143 participants (63 years ± 13, 48 females) who underwent third-generation dual-source DECT and DWI between November 2014 and October 2022 were included. Among these, 83 received a final diagnosis of pancreatic cancer, 20 had pancreatitis, and 40 had no evidence of pancreatic pathologies. Data comparisons were performed using chi-square statistic tests, one-way ANOVA, or two-tailed Student’s t-test. For the assessment of the association of texture features with overall survival, receiver operating characteristics analysis and Cox regression tests were used. Results: Malignant pancreatic tissue differed significantly from normal or inflamed tissue regarding radiomics features (overall P&lt; .001, respectively) and iodine uptake (overall P&lt; .001, respectively). The performance for the distinction of malignant from normal or inflamed pancreatic tissue ranged between an AUC of ≥ 0.995 (95% CI, 0.955–1.0; P&lt; .001) for radiomics features, ≥ 0.852 (95% CI, 0.767–0.914; P&lt; .001) for DECT-IC, and ≥ 0.690 (95% CI, 0.587–0.780; P= .01) for DWI, respectively. During a follow-up of 14 ± 12 months (range, 10–44 months), the multiparametric approach showed a moderate prognostic power to predict all-cause mortality (c-index = 0.778 [95% CI, 0.697–0.864], P= .01). Conclusions: Our reported multiparametric approach allowed for accurate discrimination of pancreatic cancer and revealed great potential to provide independent prognostic information on all-cause mortality.

Pedrolide (1), a diterpenoid with an unprecedented carbon skeleton, pedrolane, containing a bicycle[2.2.1]heptane system, is reported. This structural feature is hypothesized to involve an intramolecular cyclization, via Michael addition, and a ring contraction, via 1,2-alkyl shift or a Pinacol rearrangement of rings A and B, from a tigliane-type 5/7/6/3-tetracyclic ring precursor. The structure of 1was established using spectroscopic techniques, single-crystal X-ray diffraction, and ab initiocalculations. Pedrolide reversed multidrug resistance mediated by P-glycoprotein.

Supplemental Digital Content is available in the text.

Supplemental digital content is available in the text.

One of the most startling mathematical discoveries of the nineteen century was the existence of plane-filling curves. As is well known, the first example of such a curve was given by the Italian mathematician Giuseppe Peano in 1890. Subsequently, other examples of plane-filling curves appeared, with some of them having n-dimensional analogues. However, the expressions of the coordinates of the Peano curve are not easily extendable to arbitrary ndimensions. In fact, the only known extension of the Peano curve to an n-dimensional space-filling curve, made by Stephen Milne in 1982, is rather geometric and makes it difficult to establish basic properties of these curves, such as continuity and nowhere differentiability, as well as more advanced properties, such as uniform distribution of the coordinate functions. Here, we will introduce in a completely analytical way the n-dimensional version of the Peano curve. More precisely, for a given integer  n≥2,we will define (by means of identities) the  ncoordinate functions of a continuous and surjective map from a closed interval to the unit n-dimensional cube of  Rn,which, for the particular case  n=2,agrees with the original Peano curve. With this description, as we shall see, one can establish all the properties we mentioned above, and also calculate the Hausdorff dimension of the graphs of the coordinate functions of this curve.

An experimental investigation was carried out to study the convection heat transfer and pressure drop of oil-based multi-walled carbon nanotube nanofluids. The necessary data were acquired for laminar flow in the thermal entrance region. Nanofluids were produced at different mass concentrations (0.005%, 0.010% and 0.015%) using the two-step method. The thermophysical properties of nanofluids, thermal conductivity, viscosity and density, were experimentally measured. A surface treatment of the nanoparticles using oleic acid was performed. The stability of nanofluids was estimated with a UV–VIS spectrophotometer. The results of the heat transfer coefficient revealed increments with the presence of carbon nanotubes. Regarding the pressure drop, the experimental results suggested slight increases with the addition of particles. The results of UV–VIS spectrophotometry demonstrate that nanofluids with surface treatment of nanoparticles have better stability when compared to nanofluids without surface treatment. Finally, a figure of merit was proposed to evaluate the results obtained, which relates the increase in heat transfer as a function of the increase in pumping power.

Supplemental digital content is available in the text.