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An important issue in power distribution nowadays is the need to optimize medium-voltage networks serving urban areas. This paper shows how an evolutionary algorithm can be used as the basis for the type of efficient algorithm such optimization demands. The search for an optimal network solution will be restricted to a graph defined from the urban map, so each graph branch represents a trench. The solution space (networks) is assumed with "loop feeder circuits": networks with two electrical paths from the hv/mv substations to the customers. In the optimization process, the investment and loss load costs are considered taking into account the constraints of conductor capacities and voltage drop. The investment costs will take into account that some cables can be lying in the same trench. The process was applied for a Spanish city of 200,000 inhabitants. [ABSTRACT FROM PUBLISHER]

The purpose of this paper is to establish algorithms in the design of rural low-voltage (lv) distribution networks. Planning of rural lv distribution networks involves the optimal design of radial configuration and location of mv/lv substations considering cost functions. In this work both goals are considered by taking into account different conductors, voltage drop constraints, power losses in lines, and deterministic loads. The algorithms developed in this paper are based on dynamic programming and were implemented on large-scale rural lv distribution networks, but they could also be used for other network optimization. [ABSTRACT FROM PUBLISHER]

Design of optimal layout for medium-voltage (MV) power networks is a common issue in electrical distribution planning. Technical constraints (radial structure, voltage drops, and equipment capacity) and reliability limits must be fulfilled. The function for minimizing includes investments, power losses, and quality of supply costs. We present an improved algorithm based on a branch exchange technique to solve large-scale problems. A heuristic algorithm for solving a Euclidean Steiner problem is used to improve the network by including transshipment nodes. [ABSTRACT FROM PUBLISHER]

Whether cirrhotic patients with Streptococcus bovis bacteremia have an increased risk of colorectal neoplasm is uncertain. A multicentric retrospective cohort study was conducted investigating associations between S. bovis biotype and species, cirrhosis, and colorectal neoplasm. Out of 779 patients with S. bovis bacteremia, 69 (8.7%) had cirrhosis. No differences were found in the prevalence of colorectal neoplasm between cirrhotic and non-cirrhotic patients undergoing colonoscopy. Among cirrhotic patients, prevalence of colorectal neoplasms was higher in S. bovis biotype I (S. gallolyticus) bacteremia (80%) than in S. bovis biotype II (33.3%; p < 0.007). In conclusion, risk of colorectal neoplasm is high among cirrhotic patients with S. gallolyticus bacteremia., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Nanoconfinement is one of the most intriguing nanoscale effects and affects several physical and chemical properties of molecules and materials, including viscosity, reaction kinetics, and glass transition temperature. In this work, liquid nuclear magnetic resonance (NMR) was used to analyze the behavior of 2,4-pentadienone in ordered mesoporous materials with a pore diameter of between 3 and 10 nm. The liquid NMR results showed meaningful changes in the hydrogen chemical shift and the keto-enol chemical equilibrium, which were associated with the pore diameter, allowing the authors to observe the effects of nanoconfinement. An interesting phenomenon was observed where the chemical equilibria of 2,4-pentadienone confined in a mesoporous material with a pore diameter of 3.5 nm was similar to that obtained with free (bulk) 2,4-pentadienone in larger pore materials. Another interesting result was observed for the enthalpy and entropy of the tautomeric equilibria of 2,4-pentadienone confined in mesoporous materials with a 5.5 nm pore diameter being -7.9 kJ mol -1 and -15.9 J mol -1 .K. These values are similar to those obtained by dimethyl sulfoxide. This phenomenon indicates the possible use of ordered mesoporous materials as a reaction substitute in organic solvents. It was further observed that while the values of enthalpy (ΔH) and entropy (ΔS) had been modified by confinement, the Gibbs free energy (ΔG) value remained closer to that observed in free (bulk) 2,4-pentadienone. It is expected that this study will help in understanding the effects of nanoconfinement and provide a simple method to employ NMR techniques to analyze these phenomena.

Herein we describe NMR experiments and structural modifications of 4-methyl-2-phenylpyrimidine-N-acylhydrazone compounds (aryl-NAH) in order to discover if duplication of some signals in their ¹H- and ¹³C-NMR spectra was related to a mixture of imine double bond stereoisomers (E/Z) or CO-NH bond conformers (syn and anti-periplanar). NMR data from NOEdiff, 2D-NOESY and ¹H-NMR spectra at different temperatures, and also the synthesis of isopropylidene hydrazone revealed the nature of duplicated signals of a 4-methyl-2-phenylpyrimidine-N-acylhydrazone derivative as a mixture of two conformers in solution. Further we investigated the stereoelectronic influence of substituents at the ortho position on the pyrimidine ring with respect to the carbonyl group, as well as the electronic effects of pyrimidine by changing it to phenyl. The conformer equilibrium was attributed to the decoplanarization of the aromatic ring and carbonyl group (generated by an ortho-alkyl group) and/or the electron withdrawing character of the pyrimidine ring. Both effects increased the rotational barrier of the C-N amide bond, as verified by the DG(≠) values calculated from dynamic NMR. As far as we know, it is the first description of aryl-NAH compounds presenting two CO-NH bond- related conformations.

Herein, we describe the synthesis and pharmacological evaluation of novel N-phenylpyrazolyl-N-glycinyl-hydrazone derivatives that were designed as novel prototypes of p38 mitogen-activated protein kinase (MAPK) inhibitors. All of the novel synthesized compounds described in this study were evaluated for their in vitro capacity to inhibit tumor necrosis factor α (TNF-α production in cultured macrophages) and in vitro MAPK p38α inhibition. The two most active anti-TNF-α derivatives, (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N'-((4-(2-morpholinoethoxy)naphthalen-1-yl)methylene)acetohydrazide (4a) and (E)-2-(3-tert-butyl-1-phenyl-1H-pyrazol-5-ylamino)-N'-(4-chlorobenzylidene)acetohydrazide (4f), were evaluated to determine their in vivo anti-hyperalgesic profiles in carrageenan-induced thermal hypernociception model in rats. Both compounds showed anti-inflammatory and antinociceptive properties comparable to SB-203580 used as a standard drug, by oral route at a dose of 100 µmol/kg. This bioprofile is correlated with the ability of NAH derivatives (4a) and (4f) suppressing TNF-α levels in vivo by 57.3 and 55.8%, respectively.

Objectives: We sought to evaluate the clinical use of linezolid for the treatment of neurosurgical infections., Methods: Retrospective observational study of a cohort of hospitalized patients who received linezolid for a culture-positive neurosurgical infection from July 2004 to February 2009 in a tertiary hospital in Spain., Results: Seventeen patients were included in the study. Main comorbidities among these patients included one or more of the following: subarachnoidal or intraventricular hemorrhage (n=8), solid neurological cancer (n=7), corticosteroids(n=9) and hydrocephalus (n=6). Eight patients underwent a craniotomy and fourteen patients had an external ventricular drainage (EVD) as predisposing factors for infection. Meningitis was the most common infection (11; 64.7%), followed by ventriculitis (4; 23.5%) and brain abscesses (2;11.8%). The main causative organisms were coagulase-negative Staphylococcus spp. (13; 76.5%). Linezolid was used as the initial therapy in 8 episodes, after therapy failure in 6 and for other reasons in 3. The oral route was used in 9 (52.9%) episodes; linezolid was initiated orally in 2 cases. The mean duration of treatment was 26.5 days (range 15-58). No adverse events were reported. Sixteen (94.1%) patients were considered cured.There was one recurrence. The mean length of hospital stay was 45.6 (range 15-112) days and the mean duration of follow-up was 7.2 (range 0.4-32) months. No related deaths occurred during active episodes., Conclusions: Linezolid was mainly indicated in post-neurosurgical EVD-associated infections due to coagulase-negative Staphylococcus spp. It was used as initial therapy in most cases. A high rate of clinical cure was observed and no related adverse events were reported. More than half of the patients were benefited by the advantages of the oral route of administration.

Interesting anisotropic effects were observed for phenylglyoxamides and their respective mandelamides. Such effects were observed in experimental (1)H and (13)C NMR (in CDCl(3), CD(3)OD, and DMSO-d(6) solvents) and in some cases with good correlation to theoretical (1)H and (13)C NMR DFT-GIAO (B3LYP/6-311++G**//B3LYP/6-31G*) calculations. A systematic conformational analysis of these compounds was performed in a two-step methodology, using PM3 and DFT (B3LYP/6-31G*) calculations; with good accomplishment and computational time economy. It was observed that intramolecular hydrogen bonding plays a significant role in the conformation of such compounds. Finally, a geminal nonequivalence of an N-CH(2) moiety, in one of the alkyl side chain (R1 = R2), was found for the tertiary mandelamides studied., (2008 John Wiley & Sons, Ltd.)

Fusarium polyphialidicum caused a corneal ulcer in a Spanish man. Diagnosis was established by a histopathological study and repeated cultures. The isolate was clearly resistant in vitro to the antifungal agents tested. This is the first case of human or animal mycosis by this rare fungus.

We hereby report the case of a 22-year-old patient with a final diagnosis of type II cystic adenomatoid malformation, who was hospitalized due to repeated pulmonary infections. The radiographic study demonstrated a worrying image of a pulmonary mass. The different studies performed, did not put forward the diagnosis, so at last the patient was proposed a thoracotomy for diagnostic and therapeutic purposes.

Background: We present a case of infected atrial myxoma simulating bacterial endocarditis., Material and Methods: A 75 year old male, without any antecedents of interest, with fever an evolution a month, and a cardiac murmur. Blood cultures were practiced by BACTEC N.R. 730 system. The diagnosis was performed by the bidimensional and transesophageal echo, and confirmed with the resection from surgery. The method of bibliographical review used, has been the data base of comprehensive Medline, cvc since 1987 up June 1992 and the Oncodise's Concerlit archive from the year 1985 up to june 1992 the date base of the IME (Indice Médico Español) was also review up to April 1992., Results: The blood cultures were positive, 7/7 Streptococcus viridans and 3/7 a Staphylococcus epidermidis resistant to meticiline, we them with the same antibiogram. Echocardiography and angiography show a lef atrial mass, surgical resection of the mass, confirmed the hystological diagnostic of the myxoma and signs of infection., Conclusions: This is the first case in our country, with shows the rarity of it. We analyze the differential diagnosis with the non infected myxoma and the bacterial endocarditis. We think that there should be an early surgical treatment, together with antibiotic therapy, due to the high incidence of embolism in theses patients.