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This article discusses a case report of a 20-year-old patient with cervical agenesis and upper third vaginal atresia. The patient experienced cyclical pelvic pain and was previously diagnosed with partial vaginal atresia. Preoperative imaging revealed various abnormalities, including a thick transverse vaginal septum, a partial septate uterus, and a completely obstructed uterine outflow tract. Intraoperative ultrasound was used to confirm the absence of the cervix and guide the surgical management, which involved a laparoscopic hysterectomy with bilateral salpingectomy. The article highlights the value of intraoperative ultrasound in improving the characterization of complex congenital abnormalities. [Extracted from the article]

The present work is motivated by recent experiments aimed to measure the propagation velocity of bound electromagnetic (EM) field (Missevitch, et al. in EPL 93:64004, 2011; de Sangro et al. in Eur Phys J C 75:137, 2015) that reveal no retardation in the absence of EM radiation. We show how these findings can be incorporated into the mathematical structure of special relativity theory that allows us to reconsider some selected problems of classical and quantum electrodynamics. In particular, we come to the conclusion that the total four-momentum for a classical system "particles plus fields" ought to be a present state function of moving charges if EM radiation is negligible. In quantum domain, we analyze novel definition of the momentum operator recently suggested in the study of quantum phase effects (Kholmetskii et al. in Sci. Rep. 8:11937, 2018). It implies that bound EM field energy and momentum are to be present state functions, too. Being in agreement with reported experiments, these conclusions suggest the necessity to carry out more precise experimental verifications for additional and independent determination of propagation properties of bound EM fields. A scheme of a possible experiment on this subject is also proposed. [ABSTRACT FROM AUTHOR]

We start with the general approach based on conventional solutions to Maxwell’s equations and show that in the near zone of macroscopic electromagnetic sources the electromotive force produced in receiving loop antenna is intimately linked to the fundamental structure as well as to causal properties of the classical electromagnetic field as a superposition of bound and radiation components. As a consequence, we propose and implement a direct experimental procedure for the correct identification of retarded positions of bound field contributions on the oscilloscope time scale as a function of a distance from the emitting loop antenna. It provides unambiguous empirical information on causal characteristics of bound electromagnetic fields. According to the observation of no retardation inside the near zone of the emitting loop antenna, the experimental evidence for nonlocal properties of bound electromagnetic fields is reported. [ABSTRACT FROM AUTHOR]

We start with the fact that the actual consensus on the empirical verification of the standard retardation condition does not take into account the complex structure of the whole electromagnetic field in the near zone. The most rigorous and methodologically consistent way to the empirical test of the causal behavior of the whole EM field should be based on testing causal properties for each component—velocity dependent (bound) and acceleration dependent (radiation)—taken separately. Preliminary discussions on the relative contribution of bound and radiation terms for an idealized magnetic dipole provided us with a methodological approach to causal characteristics of bound fields. In view of practical implementation of this method, we made an analysis of the finite size loop antennas. The use of multisection loop antennas was fully justified by a substantial rise of the ratio of bound-to-radiation field strength. Finally, we effected numerical calculations, taking into account particular experimental settings. Comparison with the experimentally obtained data showed considerable discrepancy with the predictions of the standard electromagnetic theory. A possible interpretation in terms of nonlocal properties of bound fields in near zone is proposed. [ABSTRACT FROM AUTHOR]

Aging and disease-related malnutrition are well associated with loss of muscle mass and function. Muscle mass loss may lead to increased health complications and associated increase in health care costs, especially in hospitalized individuals. High protein oral nutritional supplements enriched with β-hydroxy-β-methylbutyrate (HP-ONS+HMB) have been suggested to provide benefits such as improving body composition, maintaining muscle mass and function and even decreasing mortality rates. The present review aimed to examine current evidence on the effect of HP-ONS+HMB on muscle-related clinical outcomes both in community and peri-hospitalization patients. Overall, current evidence suggests that therapeutic nutrition such as HP-ONS+HMB seems to be a promising tool to mitigate the decline in muscle mass and preserve muscle function, especially during hospital rehabilitation and recovery. [ABSTRACT FROM AUTHOR]

Time quantification of Monte Carlo steps is studied by the implementation of a new technique which takes into account the realistic size of thermal fluctuations of magnetization along with Landau–Lifshitz–Gilbert dynamic correlations. The computational model has been specifically developed for an ensemble of isolated single-domain particles. The numerical results have been compared with Langevin dynamics calculations and theoretically predicted Brown’s asymptotes for relaxation time of single spin system. In addition we demonstrated that real time quantification of Monte Carlo steps is also possible for different time scales. Implementation of real time scales into Monte Carlo calculations for different sizes of time steps is shown to be convergent to the expected value if the Monte Carlo acceptance rate is taken into account. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Human milk oligosaccharides (HMO) are involved in many biological functions influencing infant health. Although HMO act locally at the intestine, recent evidence has demonstrated that HMO are partially incorporated into the systemic circulation of breast-fed infants. In the last few years, a large amount of research has been conducted using preclinical models to uncover new biological functions of HMO. The aim of this study was to evaluate the absorption and urine excretion of HMO in rats. We administered a single oral dose of the following HMO: 2'-fucosyllactose (2'-FL), 6'-sialyllactose and lacto-N-neotetraose at different concentrations to adult rats. The time course of absorption of HMO into the bloodstream and their appearance in urine was studied. Our results showed that rats, similar to human infants, are able to effectively absorb a portion of HMO from the intestine into plasma and to excrete them in urine. On the basis of this, we also conducted a specific kinetic absorption study with 2'-FL, the most predominant HMO in human milk, in 9–11-d-old rat pups. Our results confirmed that a significant amount of 2'-FL was absorbed into the systemic circulation and subsequently excreted in urine during lactation in rats in a dose-depended manner. We also found basal levels of these HMO in plasma and urine of adult rats as well as rat pups as a natural result of nursing. Our data suggest that the rat may be a useful preclinical model that provides new insights into the metabolism and functions of HMO. [ABSTRACT FROM PUBLISHER]

Examines the relaxation behavior of systems with high structure homogeneity and reduced dimensionality and the behavior of simple systems as isolated particles. Analysis of the relaxation behavior of single-particle-type systems; Description of the relaxation behavior of polycrystalline-type systems with distributed anisotropy easy axes; How the relaxation curves in the systems were obtained.

Examines the thermally activated demagnetization behavior of a 1D model polycrystalline material having distributed local easy axes directions. Evaluation of the time dependence of the magnetization under different constant demagnetizing fields as basis of analysis.

Presents a study which focused on the relaxation of simple and magnetic systems. Description of the model; Results and discussion; Conclusion.

Copyright of Revista Facultad Nacional de Salud Pública is the property of Universidad de Antioquia, Facultad Nacional de Salud Publica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main objective of the present work was to develop a method to determine β-hydroxymethylbutyrate (HMB) and leucine (Leu) in culture media and brain microdialysates. An accurate, selective, and cost-effective method, based on the use of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), was developed for the identification and quantification of both compounds. The method consisted of sample dilution, direct injection onto the chromatographic equipment, and quantification with a triple quadrupole mass spectrometer using an electrospray ionization interface in positive mode. The procedure and the UHPLC-MS/MS parameters were accurately optimized to achieve the highest recoveries and to enhance the analytical characteristics of the method. For chromatographic separation, an Acquity UPLC BEH Hilic column using acetonitrile-water gradient with formic acid as additive was employed. The total run time was 4 min. The limits of detection (LODs) obtained ranged from 0.01 to 0.04 μg mL, and the limits of quantification (LOQs) ranged from 0.04 to 0.12 μg mL. Precision (expressed as relative standard deviation) was lower than 15 %, and the determination coefficient ( R) was higher than 99.0 % with a residual deviation for each calibration point lower than ±25 %. Mean recoveries were between 85 and 115 %. The method was successfully applied to the analysis of both compounds, HMB and Leu, in samples obtained from an experiment of blood-brain barrier (BBB) passage in vitro and to an experiment of brain microdialysis in rats in vivo after an oral challenge with HMB to detect its appearance in the brain. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work is motivated by our recent experimental results [2-4] that indicate on anomalously small retardation of bound (or velocity-dependent) electromagnetic (EM) fields in the near zone of an emitter, whereas in the far zone the retardation tends to the standard value determined by the velocity of light c. Such anomaly is specific only for bound field component, while EM radiation has the constant propagation velocity c in the entire space. One possible explanation of these experimental results can be linked to our earlier finding [6, 8] that conventional EM energy-momentum (EMEM) tensor describes bound and radiative EM fields only in spatial regions free of charges and currents. In this work we show that an additional term has to be included into the standard EMEM tensor in order to make viable the description of the whole system of \charges plus fields". Such approach to the EMEM tensor actually admits anomalously small retardation of bound EM fields in regions very close to a field source, providing the standard propagation in the far zone. Some special implications are also discussed. [ABSTRACT FROM AUTHOR]

Recent studies revealed a negative association between acculturation and sun-safe behaviors, possibly mediated by education level, health status, and social networks. We sought to elucidate this relationship by exploring the moderating effects of gender and health insurance on each mediated path. We used data from 496 Latino respondents to the 2005 Health Information National Trends Survey. Acculturation, assessed by a four-item index, was the primary predictor; use of sunscreen and protective clothing were the primary outcomes, assessed by frequency scales. Moderated mediation was tested with an established causal moderation method. The mediated association between acculturation, education level and sunscreen use might be stronger among women than men ( P < 0.08). We found no evidence of moderated mediation for use of protective clothing. The findings suggest ways of refining the theoretical and empirical rationale for sun safety research and interventions with Latinos. Studies should replicate these models with longitudinal data. [ABSTRACT FROM AUTHOR]

Background: The goal of this study was to develop an animal model of intestinal injury induced by 5-fluorouracil (5-FU) in pigs. Methods: Six domestic pigs were used as control (healthy group) and another 6 malnourished pigs orally received 5-FU (treated group). After 4 weeks of treatment, pigs were sacrificed and jejunum, ileum and colon were isolated for histological, immunological and biochemical analyses. Results: 5-FU caused a decrease in the intestinal mass. Disaccharidase, and phosphate alkaline activities, and glutathione redox cycle were disrupted by 5-FU. Histopathological alterations in the crypts and villous were greater in the small intestine than in the colon. 5-FU decreased the number of peripheral and intestinal leukocytes, promoting an increase in T-cytotoxic cells and a decrease in T-helper and B cells. Conclusion: This pig model of intestinal dysfunction closely mimics the common side effects of cancer chemotherapy in humans, and provides a useful tool for evaluating novel antimucotoxic agents. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Close insight into mathematical and conceptual structure of classical field theories shows serious inconsistencies in their common basis. In other words, we claim in this work to have come across two severe mathematical blunders in the very foundations of theoretical hydrodynamics. One of the defects concerns the traditional treatment of time derivatives in Eulerian hydrodynamic description. The other one resides in the conventional demonstration of the so-called Convection Theorem. Both approaches are thought to be necessary for cross-verification of the standard differential form of continuity equation. Any revision of these fundamental results might have important implications for all classical field theories. Rigorous reconsideration of time derivatives in Eulerian description shows that it evokes Minkowski metric for any flow field domain without any previous postulation. Mathematical approach is developed within the framework of congruences for general four-dimensional differentiable manifold and the final result is formulated in form of a theorem. A modified version of the Convection Theorem provides a necessary cross-verification for a reconsidered differential form of continuity equation. Although the approach is developed for one-component (scalar) flow field, it can be easily generalized to any tensor field. Some possible implications for classical electrodynamics are also explored. [ABSTRACT FROM AUTHOR]

The historical background of the 19th century electromagnetic theory is revisited from the standpoint of the opposition between alternative approaches in respect to the problem of interactions. The 19th century electrodynamics became the battle-field of a paramount importance to test existing conceptions of interactions. Hertz’s experiments were designed to bring a solid experimental evidence in favor of one of them. The modern scientific method applied to analyze Hertz’s experimental approach as well as the analysis of his laboratory notes, dairy and private letters show that Hertz’s ‘‘crucial’’ experiments cannot be considered as conclusive at many points as it is generally implied. We found that alternative Helmholtz’s electrodynamics did not contradict any of Hertz’s experimental observations of transverse components as Maxwell’s theory predicted. Moreover, as we now know from recently published Hertz’s dairy and private notes, his first experimental results indicated clearly on infinite rate of propagation. Nevertheless, Hertz’s experiments provided no further explicit information on non-local longitudinal components which were such an essential feature of Helmholtz’s theory. Necessary and sufficient conditions for a decisive choice on the adequate account of electromagnetic interactions are discussed from the position of modern scientific method. [ABSTRACT FROM AUTHOR]

In the area of goodness-of-fit there is a clear distinction between the problem of testing the fit of a continuous distribution and that of testing a discrete distribution. In all continuous problems the data is recorded with a limited number of decimals, so in theory one could say that the problem is always of a discrete nature, but it is a common practice to ignore discretization and proceed as if the data is continuous. It is therefore an interesting question whether in a given problem of test of fit, the “limited resolution” in the observed recorded values may be or may be not of concern, if the analysis done ignores this implied discretization. In this article, we address the problem of testing the fit of a continuous distribution with data recorded with a limited resolution. A measure for the degree of discretization is proposed which involves the size of the rounding interval, the dispersion in the underlying distribution and the sample size. This measure is shown to be a key characteristic which allows comparison, in different problems, of the amount of discretization involved. Some asymptotic results are given for the distribution of the EDF (empirical distribution function) statistics that explicitly depend on the above mentioned measure of degree of discretization. The results obtained are illustrated with some simulations for testing normality when the parameters are known and also when they are unknown. The asymptotic distributions are shown to be an accurate approximation for the true finite n distribution obtained by Monte Carlo. A real example from image analysis is also discussed. The conclusion drawn is that in the cases where the value of the measure for the degree of discretization is not “large”, the practice of ignoring discreteness is of no concern. However, when this value is “large”, the effect of ignoring discreteness leads to an exceded number of rejections of the distribution tested, as compared to what would be the number of rejections if no rounding is taking into account. The error made in the number of rejections might be huge. [ABSTRACT FROM AUTHOR]

It is generally accepted that solutions of so called 'free' Maxwell equations for ϱ = 0 (null charge density at every point of the whole space) describe a free electromagnetic field for which flux lines neither begin nor end in a charge). In order to avoid ambiguities and unacceptable approximation which have place in the conventional approach in respect to the free field concept, we explicitly consider three possible types of space regions: ( i) 'isolated charge-free' region, where a resultant electric field with the flux lines which either begin or end in a charge is zero in every point, for example, inside a hollow conductor of any shape or in a free-charge universe; ( ii) 'non-isolated charge-free' region, where this electric [see ( i)] field is not zero in every point; and ( iii) 'charge-neutral' region, where point charges exist but their algebraic sum is zero. According to these definitions a strict mathematical interpretation of Maxwell's equations gives following conclusions: (1) In 'isolated charge-free' regions electric free field cannot be unconditionally understood neither as a direct consequence of Maxwell's equations nor as a valid approximation: it may be introduced only as a postulate; nevertheless, this case is compatible is the existence of a time-independent background magnetic field. (2) In both 'charge-neutral' and 'non-isolated charge-free' regions, where the condition ϱ = δ function or ϱ = 0 respectively holds, Maxwell's equation for the total electric field have non-zero solutions, as in the conventional approach. However, these solution cannot be strictly identified with the electric free field. This analysis gives rise to the reconsideration of the free-electromagnetic field concept and leads to the simplest implications in respect to charge-neutral universe. [ABSTRACT FROM AUTHOR]

A charge q moving in a reference laboratory system with constant velocity V in the X-axis produces in the Z-axis a longitudinal, phase-free, vacuum magnetic field which is identified as the radiated B (3) field of Evans, Vigier and others. [ABSTRACT FROM AUTHOR]

We discuss, in terms of 1D and 2D micromagnetic models, the basic characteristics of the demagnetization mechanisms acting in hard magnetic materials. This includes the study of the hysteretic and relaxational processes and, particularly, the investigation of the temperature dependence of coercivity. From our results we conclude that, even in highly anisotropic materials, demagnetization should be described in terms of nucleation and propagation of finite magnetic moment structures of the domain wall type. [ABSTRACT FROM PUBLISHER]

Presents a study which developed an integrated numerical approach for the simulation of magnetic relaxation. Use of Monte Carlo technique with correlations and quantified time steps in the simulation; Results and discussion; Conclusions.

Discusses the relaxation properties of a hard magnetic system with distributed easy axis directions. Description of the micromagnetic model; Discussion of the results.

This work addresses the problem of energy consumption time series forecasting. In our approach, a set of time series containing energy consumption data is used to train a single, parameterised prediction model that can be used to predict future values for all the input time series. As a result, the proposed method is able to learn the common behaviour of all time series in the set (i.e., a fingerprint) and use this knowledge to perform the prediction task, and to explain this common behaviour as an algebraic formula. To that end, we use symbolic regression methods trained with both single- and multi-objective algorithms. Experimental results validate this approach to learn and model shared properties of different time series, which can then be used to obtain a generalised regression model encapsulating the global behaviour of different energy consumption time series. [ABSTRACT FROM AUTHOR]