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The paper describes the theory and practice associated with the torsional quartz-crystal viscometer for the measurement of the viscosity of Newtonian Fluids. It is an instrument that has been less often used than its quality merits, but it has the distinct advantages, shared with the vibrating-wire device, that it involves no bulk motion of fluid or a solid and that all measurements can be electrical. The temperature range that can be covered by the instrument is from 2 to 650 K and pressures have reached as much as 100 MPa. The review summarizes the most recent theory of the instrument and carefully sets out all of the many conditions that have to be satisfied by design so that a practical instrument conforms to the theory. Most of the conditions are readily satisfied. Two working equations are presented that could be used to evaluate the viscosity using the frequency at resonance of the crystal and the bandwidth of that resonance when the crystal is immersed in the fluid and in vacuo. It is explained that at present only one of these equations should be used for the evaluation. Several configurations of instruments that have been employed for measurements over a wide range of conditions are briefly described as well as the corrections necessary to operate the instrument with the highest accuracy. The overall relative uncertainty attainable with the instrument ranges from 0.005 to 0.02 at a 95% confidence level, depending upon the fluid density. [ABSTRACT FROM AUTHOR]

The influence of metal ions on the structure of amyloid- β (Aβ) protofibril models was studied through molecular dynamics to explore the molecular mechanisms underlying metal-induced Aβ aggregation relevant in Alzheimer's disease (AD). The models included 36-, 48-, and 188-mers of the Aβ42 sequence and two disease-modifying variants. Primary structural effects were observed at the N-terminal domain, as it became susceptible to the presence of cations. Specially when β-sheets predominate, this motif orients N-terminal acidic residues toward one single face of the β-sheet, resulting in the formation of an acidic region that attracts cations from the media and promotes the folding of the N-terminal region, with implications in amyloid aggregation. The molecular phenotype of the protofibril models based on Aβ variants shows that the AD-causative D7N mutation promotes the formation of N-terminal β-sheets and accumulates more Zn2+, in contrast to the non-amyloidogenic rodent sequence that hinders the β-sheets and is more selective for Na+ over Zn2+ cations. It is proposed that forming an acidic β-sheet domain and accumulating cations is a plausible molecular mechanism connecting the elevated affinity and concentration of metals in Aβ fibrils to their high content of β-sheet structure at the N-terminal sequence. [ABSTRACT FROM AUTHOR]

Oscillating-body viscometers have been used in the past to measure, in an absolute way, the viscosity of molten materials at high temperatures, from salts, metals, alloys, and semiconductors. However, the simultaneous use of basic or incomplete mathematical models, to mimic the experiment, and less careful engineering solutions for the design and operation of the instruments, led in the past to high discrepancies between the data obtained in several laboratories. This was caused by the incorrect use of the method's theory, less accurate solutions of the complex solutions, that involve solid state and fluid mechanics, and unreal instrument design. From these types of viscometers, oscillating-cup instruments have had the most success in measuring viscosity at high temperatures, and they will be the object of this paper. It was written as a resource for workers interested in transport properties of materials when considering its use for the absolute measurement of fluids viscosity in their work, or in judging the results of others' work when comparing data with their own. The paper starts with the most accurate theory of the method's description, followed by a discussion of its validity, application to instrument design, and consequent operation. Several constraints were identified and recommendations were made to minimize the effects of failing to satisfy them. Finally, a discussion about the uncertainty budget calculations for a real experiment is made. If all these points are followed in the design and operation of the instrument, results in global uncertainties Ur(η) between 0.02 and 0.04 are possible to obtain, up to high temperatures. If these constraints are not satisfied, erroneous measurements can be made, making comparisons and quality assessment difficult. [ABSTRACT FROM AUTHOR]

We propose a spectral collocation method to approximate the exact boundary control of the wave equation in a square domain. The idea is to introduce a suitable approximate control problem that we solve in the finite-dimensional space of polynomials of degree N ∈ N in space. We prove that we can choose a sequence of controls f N associated with the approximate control problem in such a way that they converge, as N → ∞ , to a control of the continuous wave equation. Unlike other numerical approximations tried in the literature, this one does not require regularization techniques and can be easily adapted to other equations and systems where the controllability of the continuous model is known. The method is illustrated with several examples in 1-d and 2-d in a square domain. We also give numerical evidence of the highly accurate approximation inherent to spectral methods. [ABSTRACT FROM AUTHOR]

Biomolecular systems are dependent on a complex interplay of forces. Modern force spectroscopy techniques provide means of interrogating these forces, but they are not optimized for studies in constrained environments as they require attachment to micron-scale probes such as beads or cantilevers. Nanomechanical devices are a promising alternative, but this requires versatile designs that can be tuned to respond to a wide range of forces. We investigate the properties of a nanoscale force sensitive DNA origami device which is highly customizable in geometry, functionalization, and mechanical properties. The device, referred to as the NanoDyn, has a binary (open or closed) response to an applied force by undergoing a reversible structural transition. The transition force is tuned with minor alterations of 1 to 3 DNA oligonucleotides and spans tens of picoNewtons (pN). The DNA oligonucleotide design parameters also strongly influence the efficiency of resetting the initial state, with higher stability devices (≳10 pN) resetting more reliably during repeated force-loading cycles. Finally, we show the opening force is tunable in real time by adding a single DNA oligonucleotide. These results establish the potential of the NanoDyn as a versatile force sensor and provide fundamental insights into how design parameters modulate mechanical and dynamic properties. [ABSTRACT FROM AUTHOR]

The need for new heat transfer agent for many applications, namely in the consumer electronics industry, requires materials, liquids at room temperature, with high thermal conductivity. From the different possibilities, Galinstan, a eutectic alloy of Gallium, Indium, and Tin with a melting point (Tm = 283.4 K) has been proposed for many applications, namely for replacing the toxic mercury element, used for many years. It is the purpose of this paper to report thermal conductivity measurements of Galinstan, product name Gallium/Indium/Tin Eutectic (NL-011), Ga68.4In21.5Sn10. The method used was the transient hot strip (THS), using a platinum metal-film sensor, produced by PVD in ceramic substrates, and electrically insulated with a heat-shrinkable coating. The details of the data acquisition system and measuring procedure are reported. Measurements were performed between 28 °C and 103 °C (301 K to 376 K), at atmospheric pressure, with an estimated uncertainty of 6%, and compared with available literature. Data were correlated for linear interpolation. This type of sensor is applied to molten metals for the first time, proofing to concept to future applications in molten metals and molten salts at higher temperatures. [ABSTRACT FROM AUTHOR]

We study the numerical approximation of the inverse scattering problem in the two-dimensional homogeneous isotropic linear elasticity with an unknown linear load given by a square matrix. For both backscattering data and fixed-angle scattering data, we show how to obtain numerical approximations of the so-called Born approximations and propose new iterative algorithms that provide sequences of approximations to the unknown load. Numerical evidences of the convergence for not too large loads are also given. [ABSTRACT FROM AUTHOR]

This paper aims to study the jump problem for monogenic functions in fractal hypersurfaces of Euclidean spaces. The notion of the Marcinkiewicz exponent has been taken into consideration. A new solvability condition is obtained, basing the work on specific properties of the Teodorescu transform in Clifford analysis. It is shown that this condition improves those involving the Minkowski dimension. [ABSTRACT FROM AUTHOR]

Mechanical characterization of dynamic DNA nanodevices is essential to facilitate their use in applications like molecular diagnostics, force sensing, and nanorobotics that rely on device reconfiguration and interactions with other materials. A common approach to evaluate the mechanical properties of dynamic DNA nanodevices is by quantifying conformational distributions, where the magnitude of fluctuations correlates to the stiffness. This is generally carried out through manual measurement from experimental images, which is a tedious process and a critical bottleneck in the characterization pipeline. While many tools support the analysis of static molecular structures, there is a need for tools to facilitate the rapid characterization of dynamic DNA devices that undergo large conformational fluctuations. Here, we develop a data processing pipeline based on Deep Neural Networks (DNNs) to address this problem. The YOLOv5 and Resnet50 network architecture were used for the two key subtasks: particle detection and pose (i.e. conformation) estimation. We demonstrate effective network performance (F1 score 0.85 in particle detection) and good agreement with experimental distributions with limited user input and small training sets (~ 5 to 10 images). We also demonstrate this pipeline can be applied to multiple nanodevices, providing a robust approach for the rapid characterization of dynamic DNA devices. [ABSTRACT FROM AUTHOR]

Aim: To explore the existing salivary, gingival crevicular fluid (GCF), blood, and serum biomarkers associated with grade C molar-incisor pattern (C/MIP) periodontitis in systemically healthy children and young adults. Materials and methods: Cross-sectional, case–control, and cohort studies on stage III grade C periodontitis or former equivalent diagnosis with analysis of molecular biomarkers in saliva, GCF, blood, or serum were retrieved from six databases and screened based on the eligibility criteria. The risk of bias in included studies was evaluated. Meta-analysis was planned for biomarkers assessed using the same detection methods and sample type in at least two papers. Results: Out of 5621 studies identified at initial screening, 28 papers were included in the qualitative analysis of which 2 were eligible for meta-analysis for IgG in serum samples. Eighty-seven biomarkers were assessed with the majority being higher in cases than in controls. Only the meta-analysis of total serum IgG with low heterogeneity value revealed a significant increase in its levels in C/MIPs compared to controls (standardised mean difference: 1.08; 95% CI: 0.76, 1.40). Conclusion: There is a paucity of data on biomarkers associated with molar-incisor pattern periodontitis. Although serum IgG levels are raised, other more specific biomarkers in saliva, GCF, and blood/serum may be promising but require further investigation. [ABSTRACT FROM AUTHOR]

The development of yogurt with functional characteristics from bioactive compounds such as fiber, antioxidants, and probiotics represents a novel strategy in designing value-added dairy beverages. However, biotechnological challenges are present in these bioprocesses, such as the selection of probiotic strains, as well as the correlation with the physicochemical characteristics of the fermentative metabolism of probiotic microorganisms. Therefore, yogurt could be a vehicle for including probiotic bacteria, bioactive compounds, and phytochemicals that allow synergistic effects in the development of bioprocesses with potential benefits for the host's health. Therefore, this article aims to review the current conditions of bio-yogurt production, discuss the physicochemical and bioactive composition (sugars, fiber, vitamins), and include phytochemicals from carrots to establish synergistic relationships with probiotic microorganisms to obtain a functional dairy beverage. [ABSTRACT FROM AUTHOR]

Background: Clinical studies suggest that female sex plays a protective role in the development and progression of kidney disease. Recent experimental studies indicate that in male rats early nephron loss under ongoing nephrogenesis is accompanied by severe long-term sequelae. In humans, nephron formation occurs mainly in the third trimester, ceasing with 36 weeks of gestation. Due to perinatal complications, preterm infants delivered during this vulnerable period may undergo acute nephron loss. In rats nephrogenesis persists until postnatal day 10, reflecting the situation of human preterms with persisting nephrogenesis. In our animal model of neonatal uninephrectomy, female and male rats were uninephrectomized at day 1 of life. Hypothesizing sex-dependent differences, long-term renal outcome was assessed after 1 year. Results: In both sexes, neonatal uninephrectomy was not followed by arterial hypertension at 1 year of age. Compensatory weight gain and glomerular hypertrophy of the remaining kidney occurred in uninephrectomized female and male animals. Selected markers of interstitial inflammation and fibrosis were regulated sex-dependently. The expression of monocyte chemoattractant protein-1 was increased in females, while tubulointerstitial infiltration by M1 macrophages was significantly higher in males after neonatal uninephrectomy. Neonatally uninephrectomized male rats had more glomerulosclerosis and podocyte damage compared to females, which was assessed by a semiquantitative score and desmin staining. RT-PCR revealed that after neonatal uninephrectomy in the remaining contralateral kidney of female rats the expression of candidate genes of renal development and function, i.e., wt-1, nephrin, synaptopodin, gdnf, and itga8 was higher than in males. Conclusions: Based on these observations we conclude that female sex is protective in the long-term response of the kidney to acute nephron loss under active nephrogenesis. [ABSTRACT FROM AUTHOR]

Context: Several descriptors from conceptual density functional theory (cDFT) and the quantum theory of atoms in molecules (QTAIM) were utilized in Random Forest (RF), LASSO, Ridge, Elastic Net (EN), and Support Vector Machines (SVM) methods to predict the toxicity (LD50) of sixty-two organothiophosphate compounds. The A-RF-G1 and A-RF-G2 models were obtained using the RF method, yielding statistically significant parameters with good performance, as indicated by R2 values for the training set (R2Train) and R2 values for the test set (R2Test), around 0.90. Methods: The molecular structure of all organothiophosphates was optimized via the range-separated hybrid functional ωB97XD with the 6–311 + + G** basis set. Seven hundred and eighty-seven descriptors have been processed using a variety of machine learning algorithms: RF LASSO, Ridge, EN and SVM to generate a predictive model. The properties were obtained with Multiwfn, AIMALL and VMD programs. Docking simulations were performed by using AutoDock 4.2 and LigPlot + programs. All the calculations in this work are carried out in Gaussian 16 program package. [ABSTRACT FROM AUTHOR]

In most urban cities, the correct design of the bus routes network is a critical task to design a successful transportation system. Thus, network designers rely on solving the Urban Transit Routing Problem (UTRP) to find a set of bus routes that minimises users travelling time and system operator costs. Most UTRP instances lack real-life demand data information, are very small w.r.t. typical scenarios or standards, or are randomly generated. Moreover, state-of-the-art dimensional reduction techniques use inherent features of urban transportation systems; therefore, they cannot significantly reduce the order of magnitude in complex cases. This article proposes a framework for generating UTRP instances that shrink the complexity of substantial real-life scenarios through well-known clustering algorithms and geographic database applications. The generated instances preserve the original demand behaviour and road structure by connecting central and periphery locations. We discuss and validate this proposal by applying it in a complex study case, the RED system from Santiago of Chile. [ABSTRACT FROM AUTHOR]

Enhancing CRISPR-mediated site-specific transgene insertion efficiency by homology-directed repair (HDR) using high concentrations of double-stranded DNA (dsDNA) with Cas9 target sequences (CTSs) can be toxic to primary cells. Here, we develop single-stranded DNA (ssDNA) HDR templates (HDRTs) incorporating CTSs with reduced toxicity that boost knock-in efficiency and yield by an average of around two- to threefold relative to dsDNA CTSs. Using small-molecule combinations that enhance HDR, we could further increase knock-in efficiencies by an additional roughly two- to threefold on average. Our method works across a variety of target loci, knock-in constructs and primary human cell types, reaching HDR efficiencies of >80–90%. We demonstrate application of this approach for both pathogenic gene variant modeling and gene-replacement strategies for IL2RA and CTLA4 mutations associated with Mendelian disorders. Finally, we develop a good manufacturing practice (GMP)-compatible process for nonviral chimeric antigen receptor-T cell manufacturing, with knock-in efficiencies (46–62%) and yields (>1.5 × 109 modified cells) exceeding those of conventional approaches. Combinations of single-stranded DNA repair templates and small molecules markedly enhance genome editing. [ABSTRACT FROM AUTHOR]

This study developed and evaluated an in vitro rumen incubation (IVRI) method to describe the exsheathment kinetics of Haemonchus contortus third-stage infective larvae (L3) in ruminal liquor (RL). The specific objectives were (i) to standardize the IVRI method to facilitate the contact between L3 and RL as well as the larval recovery, and (ii) to apply the IVRI method to describe the exsheathment kinetics of H. contortus and to select the best fitting nonlinear model. Incubation devices containing H. contortus larvae were incubated according to the IVRI technique in cattle RL or PBS. The incubation conditions included RL mixed with a nitrogen-rich media, maintained at 39 °C, with pH = 7.0, vented with CO2 and manual agitation. The larvae were recovered after 0, 1, 3, 6, 9, 12, and 24 h. The exsheathed and ensheathed larvae were counted to estimate the exsheathment (%) in RL or PBS. Exsheathment in RL was analyzed with nonlinear regression models: Exponential, Gompertz, Logistic, Log-Logistic, and Weibull. The models' fit was compared to select the one that best described the exsheathment kinetics. The exsheathment in RL reached 6.52%, 20.65%, 58.22%, 69.24%, 73.08%, and 77.20% in 1, 3, 6, 9, 12, and 24 h, respectively. Although the Gompertz, Weibull, and Logistic models were adequate to describe the observed exsheathment, the Log-Logistic model had the best fit. The IVRI method using bovine RL represents a suitable tool for the study of the in vitro exsheathment kinetics of H. contortus L3. [ABSTRACT FROM AUTHOR]

Current approaches for single molecule force spectroscopy are typically constrained by low throughput and high instrumentation cost. Herein, a low-cost, high throughput technique is demonstrated using microfluidics for multiplexed mechanical manipulation of up to ~4000 individual molecules via molecular fluid loading on-a-chip (FLO-Chip). The FLO-Chip consists of serially connected microchannels with varying width, allowing for simultaneous testing at multiple loading rates. Molecular force measurements are demonstrated by dissociating Biotin-Streptavidin and Digoxigenin-AntiDigoxigenin interactions along with unzipping of double stranded DNA of varying sequence under different dynamic loading rates and solution conditions. Rupture force results under varying loading rates and solution conditions are in good agreement with prior studies, verifying a versatile approach for single molecule biophysics and molecular mechanobiology. FLO-Chip enables straightforward, rapid, low-cost, and portable mechanical testing of single molecules that can be implemented on a wide range of microscopes to broaden access and may enable new applications of molecular force spectroscopy. Single molecule force spectroscopy methods are often low throughput and have high instrument cost. Here the authors report FLO-Chip, a low-cost, high throughput technique using microfluidics for multiplexed mechanical manipulation of many individual molecules via molecular fluid loading on-a-chip. [ABSTRACT FROM AUTHOR]

Background: Acute appendicitis is an infrequent pathology in children under 4 years of age, and its diagnosis is a clinical challenge that can lead to late detection. The intention of this study is to describe the clinical and surgical findings and to explore factors and outcomes associated with appendiceal perforation in patients under 4 years of age with histologically confirmed acute appendicitis. Cross-sectional study of historical data is on patients with a pathologic diagnosis of appendicitis. Clinical, surgical, and pathological variables were described. The relationship between the presence of perforation and associated factors and outcomes was explored using odds ratios (OR) and 95% confidence intervals. Results: Seventy-five patients were found between 2013 and 2019. Seventy-four cases presented with pain on palpation, 56 (75%) with signs of peritoneal irritation, and 70 (93%) with sepsis on admission to the emergency room. An ultrasound was done on 57 patients (76%), and only 26 (45%) were suggestive of appendicitis. Forty-one (55%) cases were operated on by open surgery and 34 (45%) by laparoscopy. In 61 (81%), they were perforated, and 48 (64%) presented peritonitis. Perforation was associated with increased hospital days (OR = 2.54 [1.60−4.03]), days of antibiotics (OR = 4.40 [2.09−9.25]), and admission to intensive care (OR = 9.65 [1.18−78.57]). Conclusions: Abdominal pain reported by parents, pain on abdominal palpation, and clinical criteria of sepsis on admission to the emergency room are common features. Acute appendicitis complicated by perforation leads to high morbidity due to longer antibiotic treatment, hospitalization days, admission to PICU, and postoperative ileus. [ABSTRACT FROM AUTHOR]

Purpose: Human milk (HM) composition is influenced by factors, like maternal diet and body stores, among other factors. For evaluating the influence of maternal fatty acid (FA) status on milk FA composition, the correlation between FA content in HM and in maternal plasma, erythrocytes, and adipose tissue was investigated. Methods: 223 European women who delivered at term, provided HM samples over first four months of lactation. Venous blood and adipose tissue (only from mothers who consented and underwent a C-section delivery) were sampled at delivery. FAs were assessed in plasma, erythrocytes, adipose tissue, and HM. Evolution of HM FAs over lactation and correlations between FA content in milk and tissues and between mother's blood and cord blood were established. Results: During lactation, arachidonic acid (ARA) and docosahexaenoic acid (DHA) significantly decreased, while linoleic acid (LA), alpha-linolenic acid (ALA), and eicosapentaenoic acid (EPA) remained stable. Positive correlations were observed between HM and adipose tissue for palmitic, stearic, oleic, and polyunsaturated fatty acids (PUFAs). Correlations were found between milk and plasma for oleic, LA, ARA, ALA, DHA, monounsaturated fatty acids (MUFAs), and PUFAs. No correlation was observed between erythrocytes and HM FAs. LA and ALA were more concentrated in maternal blood than in infant blood, contrary to ARA and DHA, supporting that biomagnification of LCPUFAs may have occurred during pregnancy. Conclusions: These data show that maternal adipose tissue rather than erythrocytes may serve as reservoir of PUFAs and LCPUFAs for human milk. Plasma also supplies PUFAs and LCPUFAs to maternal milk. If both, adipose tissue and plasma PUFAs, are reflection of dietary intake, it is necessary to provide PUFAs and LCPUFAs during pregnancy or even before conception and lactation to ensure availability for mothers and enough supply for the infant via HM. [ABSTRACT FROM AUTHOR]

In malignant hypertension, far more severe kidney injury occurs than in the "benign" form of the disease. The role of high blood pressure and the renin–angiotensin–aldosterone system is well recognized, but the pathogenesis of the renal injury of malignant hypertension (MH) remains incompletely understood. Using the rat model of two-kidney, one-clip renovascular hypertension in which some but not all animals develop MH, we performed a transcriptomic analysis of gene expression by RNA sequencing to identify transcriptional changes in the kidney cortex specific for MH. Differential gene expression was assessed in three groups: MH, non-malignant hypertension (NMH), and normotensive, sham-operated controls. To distinguish MH from NMH, we considered two factors: weight loss and typical renovascular lesions. Mean blood pressure measured intraarterially was elevated in MH (220 ± 6.5 mmHg) as well as in NMH (192 ± 6.4 mmHg), compared to controls (119 ± 1.7 mmHg, p < 0.05). Eight hundred eighty-six genes were exclusively regulated in MH only. Principal component analysis revealed a separated clustering of the three groups. The data pointed to an upregulation of many inflammatory mechanisms in MH including pathways which previously attracted relatively little attention in the setting of hypertensive kidney injury: Transcripts from all three complement activation pathways were upregulated in MH compared to NMH but not in NMH compared with controls; immunohistochemistry confirmed complement deposition in MH exclusively. The expression of chemokines attracting neutrophil granulocytes (CXCL6) and infiltration of myeloperoxidase-positive cells were increased only in MH rats. The data suggest that these pathways, especially complement deposition, may contribute to kidney injury under MH. Key messages: The most severe hypertension-induced kidney injury occurs in malignant hypertension. In a rat model of malignant hypertension, we assessed transcriptional responses in the kidney exposed to high blood pressure. A broad stimulation of inflammatory mechanisms was observed, but a few specific pathways were activated only in the malignant form of the disease, notably activation of the complement cascades. Complement inhibitors may alleviate the thrombotic microangiopathy of malignant hypertension even in the absence of primary complement abnormalities. [ABSTRACT FROM AUTHOR]

Purpose: Some agroindustrial by-products could be used as nutraceutical materials for small ruminants helping with their nutrition while controlling their gastrointestinal nematodes. This study evaluated the potential in vitro nutraceutical value of pod husks and leaves of three varieties of Theobroma cacao using two Haemonchus contortus isolates with different polyphenol susceptibility. Methods: Leaves and husks from three T. cacao varieties (AZT, CAL and CEY) were evaluated for their bromatological composition, in vitro dry matter digestibility and polyphenol content. Acetone:water extracts (70:30) of each plant variety were evaluated using the egg hatch and larval exsheathment inhibition tests, using two isolates (FESC and PARAISO) of H. contortus. Effective concentrations 50% (EC50) were determined for both tests. The role of polyphenols was confirmed using polyvinylpolypyrrolidone. L3 exposed to CAL leaf extract were submitted to transmission electron microscopy. Results: Both plant materials showed a good nutritional value to complement protein-rich diets for small ruminants. Extracts inhibited exsheathment of H. contortus L3 more effectively than the egg hatching, and the leaf extracts were more active than husk extracts in the L3 exsheathment inhibition. The FESC isolate was more sensitive to extracts. Polyphenols blocked exsheathment inhibition of leaf extracts. Structural damage was observed in the sheath and muscles of L3 exposed to CAL leaf extracts. Conclusion: The two T. cacao materials tested showed their potential to be used as ruminant feeds. Extracts affected H. contortus by blocking L3 exsheathment, particularly with the leaf extracts. The in vivo nutraceutical value should be confirmed in small ruminants. [ABSTRACT FROM AUTHOR]

In this paper, we mainly consider the Riemann boundary value problems for lower dimensional non-commutative Clifford algebras valued monogenic functions. The solutions are given in an explicit way and concrete examples are presented to illustrate the results. [ABSTRACT FROM AUTHOR]

An electric utility has as an objective to guarantee the continuity and quality of the service provided. In order to enforce an increase in the quality of service, the ANEEL (Portuguese for The Brazilian National Electric Energy Agency) introduced penalties in contracts with public electricity transmission utilities in case transmission facilities are taken out of service due to accidents, failures or scheduled maintenance. Traditional maintenance approaches to electric power transmission systems are based on actions taken periodically. Although these approaches aim to improve the performance of these systems, usually they do not accurately assess the impact of maintenance actions on their reliability related to the resources employed, as well as the resulting legal penalties. This paper proposes an approach for addressing this problem based on reliability/cost to find the best strategies for performing maintenance on electric power transmission equipment (assets), with a mathematical model that provides a feasible maintenance calendar while respecting the constraints of the electrical system operation. The proposed method consists of a combination of a constructive heuristic with dynamic programming, to find the best solutions for a given planning horizon. [ABSTRACT FROM AUTHOR]

Although the transition to renewable energies will intensify the global competition for land, the potential impacts driven by solar energy remain unexplored. In this work, the potential solar land requirements and related land use change emissions are computed for the EU, India, Japan and South Korea. A novel method is developed within an integrated assessment model which links socioeconomic, energy, land and climate systems. At 25–80% penetration in the electricity mix of those regions by 2050, we find that solar energy may occupy 0.5–5% of total land. The resulting land cover changes, including indirect effects, will likely cause a net release of carbon ranging from 0 to 50 gCO2/kWh, depending on the region, scale of expansion, solar technology efficiency and land management practices in solar parks. Hence, a coordinated planning and regulation of new solar energy infrastructures should be enforced to avoid a significant increase in their life cycle emissions through terrestrial carbon losses. [ABSTRACT FROM AUTHOR]

Objective: To characterize the pediatric patients presenting at the two pediatric centers in Bogotá, with first isolate urine culture of community-acquired extended-spectrum β-lactamase (ESBL)-producing enterobacteriaceae. Methods: Review of microbiological data of children between January, 2012 and December, 2018, obtained using the WHONET software. Results: A total of 2657 Escherichia coli, Klebsiella spp and Proteus mirabilis — positive urine cultures were obtained within a 6-year period; data of 132 patients were finally selected. Frequency of ESBL-producing bacteria infections in community-acquired urinary tract infections (UTI) was 5%: 123 E. coli (93.2%), 7 K. pneumoniae (5.2%), 1 K. oxytoca (0.8%), and 1 P. mirabilis (0.8%). Conclusion: A predominance of female sex, preschool children, and lower tract urinary infections were found, as well as a low frequency of comorbidities. Adequate sensitivity to amikacin and nitrofurantoin was found in this study. [ABSTRACT FROM AUTHOR]

Purpose: Labor is a complex process involving multiple para-, auto- and endocrine cascades. The interaction of cortisol, corticotropin-releasing hormone (CRH) and progesterone is essential. The action of cortisol on the human feto-placental unit is regulated by 11beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2/HSD11B2) that converts cortisol into inactive cortisone. The majority of studies on the assessment of placental 11β-HSD2 function determined indirect activity parameters. It remains elusive if indirect measurements correlate with enzymatic function and if these parameters are affected by potential confounders (e.g., mode of delivery). Thus, we compared determinants of indirect 11β-HSD2 tissue activity with its direct enzymatic turnover rate in placental samples from spontaneous births and cesarean (C)-sections. Methods: Using LC–MS/MS, we determined CRH, cortisol, cortisone, progesterone and 17-hydroxy(OH)-progesterone in human term placentas (spontaneous birth vs. C-section, n = 5 each) and measured the enzymatic glucocorticoid conversion rates in placental microsomes. Expression of HSD11B1, 2 and CRH was determined via qRT-PCR in the same samples. Results: Cortisol–cortisone ratio correlated with direct microsomal enzymatic turnover. While this observation seemed independent of sampling site, a strong influence of mode of delivery on tissue steroids was observed. The mRNA expression of HSD11B2 correlated with indirect and direct cortisol turnover rates in C-section placentas only. In contrast to C-sections, CRH, cortisol and cortisone levels were significantly increased in placental samples following spontaneous birth. Conclusion: Labor involves a series of complex hormonal processes including activation of placental CRH and glucocorticoid metabolism. This has to be taken into account when selecting human cohorts for comparative analysis of placental steroids. [ABSTRACT FROM AUTHOR]

In complexity theory, there is a widely studied grouping of optimization problems that belongs to the non-deterministic polynomial-time hard set. One of them is the set covering problem, known as one of Karp's 21 NP -complete problems, and it consists of finding a subset of decision variables for satisfying a set of constraints at the minimum feasible cost. However, due to the nature of the problem, this cannot be solved using traditional complete algorithms for hard instances. In this work, we present an improved binary version of the monkey search algorithm for solving the set covering problem. Originally, this approximate method was naturally inspired by the cognitive behavior of monkeys for climbing mountains. We propose a new climbing process with a better exploratory capability and a new cooperation procedure to reduce the number of unfeasible solutions. For testing this approach, we present a detailed computational results section, where we illustrate how this variation of the monkey search algorithm is capable of reaching various global optimums for a well-known instance set from the Beasley's OR-Library and how it outperforms many other heuristics and meta-heuristics addressed in the literature. Moreover, we add a complete statistical analysis to show the effectiveness of the proposed approach with respect to the original version. [ABSTRACT FROM AUTHOR]

The sugarcane agroindustry covers 10,184,340 ha of arable land in Brazil. Harvesting this crop requires increasingly sophisticated equipment and sugarcane uses a basal cutting system with knives. These knives deteriorate rapidly due to abrasion with silica in the soil, which makes hard coating feasible for these components. Hard coatings generally involve the addition of chromium to increase the service life of agricultural machinery parts. The need to reduce the levels of chemical elements harmful to humans and animals in agricultural soils requires a study of alternatives to substitute chromium in hard metal alloys. Based on that, this work is aimed to investigate an alternative this respect; the present study proposes a change in coating from tungsten carbide paste (WC), which contains chromium, to a titanium carbide–based coating without chromium. To this end, FCAW (flux-cored arc welding) welding process was used, with self-shielding flux-cored wire containing alloy elements that increase resistance to abrasion, thereby extending the service life of the component. Simultaneous optimization of multiple responses was used to determine proposed welding parameters. For validation purposes, abrasion wear tests with a rubber wheel and dry sand were conducted to compare resistance to abrasion between the proposed material and that used in commercial knives. Results from accelerated wear tests showed FCAW higher performance (around 48%) compared to the WC coating. This demonstrates technical feasibility of the proposed hard metal deposition process using FCAW welding aimed to increase the service life of basal cutting knives without chromium. [ABSTRACT FROM AUTHOR]

This study aimed to compare growth and slaughter performance of layer-type slow-growing Rhode Island Red male chickens grown with and without access to an area with vegetation in the tropics. Raised until 115 days of age, a total of 156, 1-day-old birds were randomly allocated to two treatments: total confinement (TC) and partial confinement (PC), with 6 replicates of 13 birds each. Birds grown under TC conditions reached a live weight of 2016.68 g while those raised with access to outdoors attained 1981.07 g, without statistical differences. Feed intake and daily feed intake were higher (P < 0.05) in birds farmed with TC management, during the last 17 days of the trial. Treatments did not significantly (P > 0.05) affect bird's other productive parameters and carcass traits. Results from this study suggested that slow-growing Rhode Island Red males may be raised with access to outdoors without any adverse effect on productive performance and carcass quality in the Mexican Tropic. Based on the results of this study, a rearing period of 84 days of age is recommended for Rhode Island Red male chickens raised in both TC and PC production systems. [ABSTRACT FROM AUTHOR]

Colloidal drug delivery systems are one of the most promising tools for the treatment of several diseases. We present a synthesis route based on four steps involving mesoporous silica-coated magnetite nanoparticles (MNPs) capped by polyelectrolyte (PE) assembling. The morphology and physical properties of the different components of the system were investigated. The magnetite phase of the iron oxide nanoparticles was identified by X-ray diffraction before their incorporation into the mesoporous silica matrix by a sol–gel process. A MCM-41-like organized hexagonal mesoporous (≈4.2 nm) structure was achieved, as ensured by the αS-plot model. Polyethylenimine PEI and sodium alginate (ALG) PE layer-by-layer capping were successfully performed by simple successive dispersions of nanoparticles in the PE solution bath. TEM images confirmed a well-organized structure, as also supported by DLS and XPS analyses, which present an increase in diameter size and distinct chemical surface composition after each step of the synthesis. The two successive coatings of the MNPs induced a significative decrease of the magnetic susceptibility but kept sufficient intensity for drug delivery assisted by an external magnetic field. To validate the system as drug delivery, in vitro tetracycline hydrochloride (TCH) loading and release studies were performed in PBS solution for 48 h. It was found that the TCH-loaded uncapped mesoporous silica NPs released more than 90% of TCH after 48 h. Meanwhile, when capped by the PEs, only 30% of the total drug amount was released, due to a hindrance of the drug diffusion by the PE layer. The present work suggests that the combination of the low cost and non-toxic hybrid system proposed has potential use in nanomedicine as a drug delivery vehicle. [ABSTRACT FROM AUTHOR]

Bioactive plant peptides have received considerable interest as potential antihypertensive agents with potentially fewer side effects than antihypertensive drugs. Here, the blood pressure-lowering effects of the Bowman-Birk protease inhibitor, BTCI, and its derived peptides, PepChy and PepTry, were investigated using normotensive (Wistar-WR) and spontaneously hypertensive rats (SHR). BTCI inhibited the proteases trypsin and chymotrypsin, respectively, at 6 µM and 40 µM, a 10-fold greater inhibition than observed with PepTry (60 µM) and PepChy (400 µM). These molecules also inhibited angiotensin converting enzyme (ACE) with IC50 values of 54.6 ± 2.9; 24.7 ± 1.1; and 24.4 ± 1.1 µM, respectively, occluding its catalytic site, as indicated by molecular docking simulation, mainly for PepChy and PepTry. Gavage administration of BTCI and the peptides promoted a decrease of systolic and diastolic blood pressure and an increase of renal and aortic vascular conductance. These effects were more expressive in SHR than in WR. Additionally, BTCI, PepChy and PepTry promoted coronary vasodilation and negative inotropic effects in isolated perfused hearts. The nitric oxide synthase inhibitor blunted the BTCI and PepChy, with no cardiac effects on PepTry. The findings of this study indicate a therapeutic potential of BTCI and its related peptides in the treatment of hypertension. [ABSTRACT FROM AUTHOR]

Bathymetry (seafloor depth), is a critical parameter providing the geospatial context for a multitude of marine scientific studies. Since 1997, the International Bathymetric Chart of the Arctic Ocean (IBCAO) has been the authoritative source of bathymetry for the Arctic Ocean. IBCAO has merged its efforts with the Nippon Foundation-GEBCO-Seabed 2030 Project, with the goal of mapping all of the oceans by 2030. Here we present the latest version (IBCAO Ver. 4.0), with more than twice the resolution (200 × 200 m versus 500 × 500 m) and with individual depth soundings constraining three times more area of the Arctic Ocean (∼19.8% versus 6.7%), than the previous IBCAO Ver. 3.0 released in 2012. Modern multibeam bathymetry comprises ∼14.3% in Ver. 4.0 compared to ∼5.4% in Ver. 3.0. Thus, the new IBCAO Ver. 4.0 has substantially more seafloor morphological information that offers new insights into a range of submarine features and processes; for example, the improved portrayal of Greenland fjords better serves predictive modelling of the fate of the Greenland Ice Sheet. Measurement(s) depth Technology Type(s) digital curation Factor Type(s) geographic location Sample Characteristic - Environment ocean floor Sample Characteristic - Location Arctic Ocean Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12369314 [ABSTRACT FROM AUTHOR]

In this paper sufficient conditions for continuous and compact embeddings of generalized higher order Lipschitz classes on a compact subset of n-dimensional real Euclidean spaces are obtained. [ABSTRACT FROM AUTHOR]

The search for new drugs remains an important focus for the safe and effective treatment of cardiovascular diseases. Previous evidence has shown that choline analogs can offer therapeutic benefit for cardiovascular complications. The current study investigates the effects of 2-(4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazin-1-yl)ethan-1-ol (LQFM032) on cardiovascular function and cholinergic-nitric oxide signaling. Synthesized LQFM032 (0.3, 0.6, or 1.2 mg/kg) was administered by intravenous and intracerebroventricular routes to evaluate the potential alteration of mean arterial pressure, heart rate, and renal sympathetic nerve activity of normotensive and hypertensive rats. Vascular function was further evaluated in isolated vessels, while pharmacological antagonists and computational studies of nitric oxide synthase and muscarinic receptors were performed to assess possible mechanisms of LQFM032 activity. The intravenous and intracerebroventricular administration of LQFM032 elicited a temporal reduction in mean arterial pressure, heart rate, and renal sympathetic nerve activity of rats. The cumulative addition of LQFM032 to isolated endothelium-intact aortic rings reduced vascular tension and elicited a concentration-dependent relaxation. Intravenous pretreatment with L-NAME (nitric oxide synthase inhibitor), atropine (nonselective muscarinic receptor antagonist), pirenzepine, and 4-DAMP (muscarinic M1 and M3 subtype receptor antagonist, respectively) attenuated the cardiovascular effects of LQFM032. These changes may be due to a direct regulation of muscarinic signaling as docking data shows an interaction of choline analog with M1 and M3 but not nitric oxide synthase. Together, these findings demonstrate sympathoinhibitory, hypotensive, and antihypertensive effects of LQFM032 and suggest the involvement of muscarinic receptors. [ABSTRACT FROM AUTHOR]

Despite demonstrating exciting potential for applications such as drug delivery and biosensing, the development of nanodevices for practical applications and broader use in research and education are still hindered by the time, effort, and cost associated with DNA origami fabrication. Simple and robust methods to perform and scale the DNA origami self-assembly process are critical to facilitate broader use and translation to industrial or clinical applications. We report a simple approach to fold DNA origami nanostructures that is fast, robust, and scalable. We demonstrate fabrication at scales approximately 100–1,500-fold higher than typical scales. We further demonstrate an approach we termed low-cost efficient annealing (LEAN) self-assembly involving initial heating at 65 °C for 10 min, then annealing at 51 °C for 2 h, followed by brief quenching at 4 °C that leads to effective assembly of a range of DNA origami structures tested. In contrast to other methods for scaling DNA origami assembly, this approach can be carried out using cheap and widely available equipment (e.g., hot plates, water baths, and laboratory burners) and uses standard recipes and materials so is readily applied to any existing or new DNA origami designs. We envision these methods can facilitate device development for commercial applications and facilitate broader use of DNA origami in research and education. [ABSTRACT FROM AUTHOR]

The objective of this paper is to develop a computational model of the fission yeast (Schizosaccharomyces pombe) cell cycle using agent-based modeling (ABM), to study the sequence of states of the proteins and time of the cell cycle phases, under the action of proteins that regulate its cell cycle. The model relies only on the conceptual model of the yeast cell cycle regulatory network, where each protein has been represented as an agent with a property called activity that represents its biological function and a stochastic Brownian movement. The results indicate that the simulated phase time did have similar results in comparison with other models using mathematical approaches. Similarly, the correct sequence of states was achieved, and the model was run under different initial states to understand its emergent behaviors. The cell reached the G1 stationary state 94% of the times when running the model under biological initial conditions and 87% of the times when running the model through all the different combinations of initial states. Such results imply that the cell was capable to fix toward the biological expected phenomena. These results show that ABM is a suitable technique to study protein-protein interactions without using, often unavailable, kinetic parameters, or differential equations. This model sets as a base for further studies that involve the cell cycle of the fission yeast, with a special attention to studies and development of drug treatments for specific types of cancer. [ABSTRACT FROM AUTHOR]

In recent years, a growing interest has been observed on the static and dynamic behavior of multi-stable structures. In this paper, a shallow bistable regular pyramidal truss composed of n equally spaced bars is investigated, allowing a deeper understanding of the static and dynamic buckling of several shallow structures, from carbon nanostructures to large geodesic domes. First an exact formulation, considering large displacements, is presented and the nonlinear equations of motion for a nodal load acting along a generic oblique direction are derived. Based on this formulation, the parametric buckling analysis of the truss under vertical static load as a function of the shallowness parameter is conducted and the equations of motion of the preloaded structure are derived. Then, the fundamental vibration frequency and nonlinear frequency-amplitude relations are obtained as a function of the static preload. The structure exhibits a two-well potential function whose geometry controls the dynamics of the preloaded structure. A detailed parametric analysis of the preloaded truss under harmonic excitation is then conducted. Emphasis is placed on the influence of the load and geometric parameters on the coexisting stable and unstable dynamic responses associated with the two-well potential function. Detailed bifurcations analyses using continuation techniques show the existence of several in-well and cross-well stable and unstable coexisting solutions. Also they permit the identification of the stability boundaries under different loading conditions. These coexisting solutions lead to topologically involved portraits of the attractor-basin response. Thus, an analysis of the evolution and erosion of the basins of attraction is performed. In a dynamic environment excitation, noise has a palpable influence on the system response. So, in the last part of the paper the influence of random noise on the topology of the coexisting basins of attraction of the system is investigated. Notwithstanding the complex nonlinear dynamics of this class of bistable structures, the analysis of the truss global dynamics may provide hints for safe structural design and novel applications of multi-stable structures. [ABSTRACT FROM AUTHOR]

In this paper is presented a novel and simple synthetic pathway for obtaining new protected and unprotected N-glucosyl amino acids from 2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl amine and Fmoc-l-amino acids. Three methodologies were evaluated, using the coupling reagents: N,N,N′,N′-Tetramethyl-O-(benzotriazol-1-yl)uronium tetrafluoroborate, diisopropylcarbodiimide and propylphosphonic acid cyclic anhydride. The obtained products using propylphosphonic acid cyclic anhydride showed less undesired species, easy purification and higher yields than the other two methodologies. Deprotection strategies widely used in solid phase peptide synthesis were applied to develop the synthetic pathway reported and achieve the final products. The protected and unprotected N-glucosyl amino acids were purified using solid phase extraction chromatography and characterized by high performance liquid Chromatography and nuclear magnetic resonance spectroscopy. Different amino acids (Fmoc-l-Asp(OtBu)OH, Fmoc-l-Phe(OH) and Fmoc-l-Lys(Boc)-OH) have been employed to demonstrate the simple and reproducible coupling methodology using propylphosphonic acid cyclic anhydride. The results showed that new protected and unprotected N-glucosyl amino acids can be obtained with high purity and the methodology could be used with any Fmoc-amino acid. The methodology developed could be considered as a synthetic tool for obtaining building blocks for glycopeptide synthesis and potential drugs candidates based on glycoconjugates. [ABSTRACT FROM AUTHOR]

Structural and electronic properties of a series of 25 phosphonate derivatives were analyzed applying density functional theory, with the exchange-correlation functional PBEPBE in combination with the 6-311++G** basis set for all atoms. The chemical reactivity of these derivatives has been interpreted using quantum descriptors such as frontier molecular orbitals (HOMO, LUMO), Hirshfeld charges, molecular electrostatic potential, and the dual descriptor [Δf(r)]. These descriptors are directly related to experimental median lethal dose (LD50), expressed as its decimal logarithm [Aobs=log10(LD50)] through a multiple linear regression equation. The proposed model predicts the toxicity of phosphonates in function of the volume (V), the load of the most electronegative atom of the molecule (q), and the eigenvalue of the molecular orbital HOMO (EHOMO). The obtained values in the internal validation of the model are: R2=82.71%, RADJ2=80.24%, F=33.5, δK=0.169, δQ=0.011, RP=0.423, RN=-0.025(-0.311), and Qboot2=75.45%. The toxicity of nine phosphonate derivatives used as test molecules was adequately predicted by the model. The theoretical results indicate that the oxygen atom of the O=P group plays an important role in the interaction mechanism between the phosphonate and the acetylcholinesterase enzyme, inhibiting the removal of the proton of the ser-200 residue by the his-440 residue. [ABSTRACT FROM AUTHOR]

DNA nanotechnology has enabled complex nanodevices, but the ability to directly manipulate systems with fast response times remains a key challenge. Current methods of actuation are relatively slow and only direct devices into one or two target configurations. Here we report an approach to control DNA origami assemblies via externally applied magnetic fields using a low-cost platform that enables actuation into many distinct configurations with sub-second response times. The nanodevices in these assemblies are manipulated via mechanically stiff micron-scale lever arms, which rigidly couple movement of a micron size magnetic bead to reconfiguration of the nanodevice while also enabling direct visualization of the conformation. We demonstrate control of three assemblies—a rod, rotor, and hinge—at frequencies up to several Hz and the ability to actuate into many conformations. This level of spatiotemporal control over DNA devices can serve as a foundation for real-time manipulation of molecular and atomic systems. [ABSTRACT FROM AUTHOR]

Scaffolded DNA origami has proven to be a powerful and efficient technique to fabricate functional nanomachines by programming the folding of a single-stranded DNA template strand into three-dimensional (3D) nanostructures, designed to be precisely motioncontrolled. Although two-dimensional (2D) imaging of DNA nanomachines using transmission electron microscopy and atomic force microscopy suggested these nanomachines are dynamic in 3D, geometric analysis based on 2D imaging was insufficient to uncover the exact motion in 3D. Here we use the individual-particle electron tomography method and reconstruct 129 density maps from 129 individual DNA origami Bennett linkage mechanisms at ~ 6-14 nm resolution. The statistical analyses of these conformations lead to understanding the 3D structural dynamics of Bennett linkage mechanisms. Moreover, our effort provides experimental verification of a theoretical kinematics model of DNA origami, which can be used as feedback to improve the design and control of motion via optimized DNA sequences and routing. [ABSTRACT FROM AUTHOR]

The multidimensional knapsack problem (MKP) is one of the widely known integer programming problems. The MKP has received significant attention from the operational research community for its large number of applications. Solving this NP-hard problem remains a very interesting challenge, especially when the number of constraints increases. In this paper we present a k-means transition ranking (KMTR) framework to solve the MKP. This framework has the property to binarize continuous population-based metaheuristics using a data mining k-means technique. In particular we binarize a Cuckoo Search and Black Hole metaheuristics. These techniques were chosen by the difference between their iteration mechanisms. We provide necessary experiments to investigate the role of key ingredients of the framework. Finally to demonstrate the efficiency of our proposal, MKP benchmark instances of the literature show that KMTR competes with the state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]