The Henstock-Kurzweil-Pettis integrals and existence theorems for the Cauchy problem

summary:In this paper we prove an existence theorem for the Cauchy problem $$x^{\prime }(t) = f(t, x(t)), \quad x(0) = x_0, \quad t \in I_{\alpha } = [0, \alpha ]$$ using the Henstock-Kurzweil-Pettis integral and its properties. The requirements on the function $f$ are not too restrictive: scalar measurability and weak sequential continuity with respect to the second variable. Moreover, we suppose that the function $f$ satisfies some conditions expressed in terms of measures of weak noncompactness

Developmental parallelism in primates

The authors examined a large random sample of skulls from two species of macaques: rhesus monkeys and cynomolgus monkeys. The skulls were measured, divided into age and sex groups and thoroughly analysed using statistical methods. The analysis shows that skulls of young rhesuses are considerably more domed, i.e. have better-developed neurocrania, than their adult counterparts. Male and female skulls, on the other hand, were found to be very similar, which means that sexual dimorphism of the rhesus macaque was suppressed. Both of these patterns are known from the human evolutionary pattern. No such parallelism to the development of Homo sapiens was found in the cynomolgus monkeys. The authors conclude that mosaic hominisation trends may have featured in the evolution of all primates. This would mean that apes were not a necessary step on the evolutionary way leading to the development of Homo sapiens, who may have started to evolve at an earlier stage of monkeys

Front-face fluorescence spectroscopy and chemometrics for quality control of cold-pressed rapeseed oil during storage

The aim of this study was to test the usability of fluorescence spectroscopy to evaluate the stability of cold-pressed rapeseed oil during storage. Freshly-pressed rapeseed oil was stored in colorless and green glass bottles exposed to light, and in darkness for a period of 6 months. The quality deterioration of oils was evaluated on the basis of several chemical parameters (peroxide value, acid value, K232 and K270, polar compounds, tocopherols, carotenoids, pheophytins, oxygen concentration) and fluorescence. Parallel factor analysis (PARAFAC) of oil excitation-emission matrices revealed the presence of four fluorophores that showed different evolution throughout the storage period. The fluorescence study provided direct information about tocopherol and pheophytin degradation and revealed formation of a new fluorescent product. Principal component analysis (PCA) performed on analytical and fluorescence data showed that oxidation was more advanced in samples exposed to light due to the photo-induced processes; only a very minor effect of the bottle color was observed. Multiple linear regression (MLR) and partial least squares regression (PLSR) on the PARAFAC scores revealed a quantitative relationship between fluorescence and some of the chemical parameters.Funding Agency Ministry of Science and Higher Education, Poland NN312428239 Poznan University of Economics and Businessinfo:eu-repo/semantics/publishedVersio

Fluorescence spectroscopy for characterization and differentiation of beers

Total luminescence and synchronous scanning fluorescence spectroscopic techniques were applied for characterization of the intrinsic fluorescence of eight different beers. Spectra were measured using different geometries to reveal the presence of similar fluorescent components. The total luminescence and synchronous fluorescence spectra exhibit a relatively intense short-wavelength emission ascribed to aromatic amino acids and less intense emission in the long-wavelength region, which may originate from B vitamins. Classification of beers based on their synchronous fluorescence spectra was performed using non-parametrical k nearest neighbours method and linear discriminant analysis. Very good discrimination was obtained in both methods with a low classification error. The results demonstrate the potential of fluorescence techniques to characterize and differentiate beers

Pain as a mediator in the temperament-alexithymia relationship in individuals suffering from rheumatoid arthritis

[Abstract] OBJECTIVE: The study aims to establish a relationship between temperament traits, symptoms of alexithymia, and pain intensity in rheumatoid arthritis. Despite the significant progress seen in the area of RA treatment, pain, often life-long, remains the predominant symptom. This constant pain and progressing disability, as well as dependence upon other people cause RA patients to experience psychological stress that can be modified by individual patient traits. Recently, several authors have underlined the need to relate personality and temperament constructs to neurobiological processes that may underlie individual differences. It seems then that patient characteristics may play a significant role in the course of the disease. PATIENTS AND METHODS: The study was performed on a group of patients (N=317) with rheumatoid arthritis diagnosed according to the current criteria of the American-European Consensus of 2010. All patients expressed voluntary consent to participate, and the study protocol was approved by the Local Ethics Committee. This was a survey-based study. It involved the application of the adult version of the Buss and Plomin EAS Temperament Questionnaire (EAS-D), which tests 3 main temperament domains: sociability, activity, and emotionality. The pain was measured on the Visual Analogue Scale (VAS). VAS is used to measure pain intensity. The level of alexithymia was tested using the Toronto Alexithymia Scale-20. The scale consists of 20 statements and includes 3 subscales that measure difficulty in describing feelings/emotions, difficulty in identifying feelings/emotions, and operational externally oriented thinking. RESULTS: The analysis revealed that alexithymia is positively correlated only with one dimension of temperament, i.e., emotionality, and with pain intensity. Moreover, high emotionality was positively correlated with pain. A simple mediation analysis revealed that pain intensity functioned as a mediator in the emotionality-alexithymia relationship. CONCLUSIONS: The observed correlations indicate that RA patients with a high level of emotionality exhibit high alexithymia as they perceive pain related to the disease symptoms more intensely. The observed mediation is partial, meaning that there are also other mediating factors in this relationship

A five-year hedonic price breakdown for desktop personal computer attributes in Brazil

The purpose of this article is to identify the attributes that discriminate the prices of personal desktop computers. We employ the hedonic price method in evaluating such characteristics. This approach allows market prices to be expressed as a function, a set of attributes present in the products and services offered. Prices and characteristics of up to 3,779 desktop personal computers offered in the IT pages of one of the main Brazilian newspapers were collected from January 2003 to December 2007. Several specifications for the hedonic (multivariate) linear regression were tested. In this particular study, the main attributes were found to be hard drive capacity, screen technology, main board brand, random memory size, microprocessor brand, video board memory, digital video and compact disk recording devices, screen size and microprocessor speed. These results highlight the novel contribution of this study: the manner and means in which hedonic price indexes may be estimated in Brazil

Screening of antioxidant properties of the apple juice using the front-face synchronous fluorescence and chemometrics

Fluorescence spectroscopy is gaining increasing attention in food analysis due to its higher sensitivity and selectivity as compared to other spectroscopic techniques. Synchronous scanning fluorescence technique is particularly useful in studies of multi-fluorophoric food samples, providing a further improvement of selectivity by reduction in the spectral overlapping and suppressing light-scattering interferences. Presently, we study the feasibility of the prediction of the total phenolics, flavonoids, and antioxidant capacity using front-face synchronous fluorescence spectra of apple juices. Commercial apple juices from different product ranges were studied. Principal component analysis (PCA) applied to the unfolded synchronous fluorescence spectra was used to compare the fluorescence of the entire sample set. The regression analysis was performed using partial least squares (PLS1 and PLS2) methods on the unfolded total synchronous and on the single-offset synchronous fluorescence spectra. The best calibration models for all of the studied parameters were obtained using the PLS1 method for the single-offset synchronous spectra. The models for the prediction of the total flavonoid content had the best performance; the optimal model was obtained for the analysis of the synchronous fluorescence spectra at Delta lambda = 110 nm (R (2) = 0.870, residual predictive deviation (RPD) = 2.7). The optimal calibration models for the prediction of the total phenolic content (Delta lambda = 80 nm, R (2) = 0.766, RPD = 2.0) and the total antioxidant capacity (Delta lambda = 70 nm, R (2) = 0.787, RPD = 2.1) had only an approximate predictive ability. These results demonstrate that synchronous fluorescence could be a useful tool in fast semi-quantitative screening for the antioxidant properties of the apple juices.info:eu-repo/semantics/publishedVersio