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Information storage, reflecting the capability of a dynamical system to keep predictable information during its evolution over time, is a key element of intrinsic distributed computation, useful for the description of the dynamical complexity of several physical and biological processes. Here we introduce a parametric approach which allows one to compute information storage across multiple timescales in stochastic processes displaying both short-term dynamics and long-range correlations (LRC). Our analysis is performed in the popular framework of multiscale entropy, whereby a time series is first "coarse grained" at the chosen timescale through low-pass filtering and downsampling, and then its complexity is evaluated in terms of conditional entropy. Within this framework, our approach makes use of linear fractionally integrated autoregressive (ARFI) models to derive analytical expressions for the information storage computed at multiple timescales. Specifically, we exploit state space models to provide the representation of lowpass filtered and downsampled ARFI processes, from which information storage is computed at any given timescale relating the process variance to the prediction error variance. This enhances the practical usability of multiscale information storage, as it enables a computationally reliable quantification of a complexity measure which incorporates the effects of LRC together with that of short-term dynamics. The proposed measure is first assessed in simulated ARFI processes reproducing different types of autoregressive dynamics and different degrees of LRC, studying both the theoretical values and the finite sample performance. We find that LRC alter substantially the complexity of ARFI processes even at short timescales, and that reliable estimation of complexity can be achieved at longer timescales only when LRC are properly modeled. Then, we assess multiscale information storage in physiological time series measured in humans during resting state and postural stress, revealing unprecedented responses to stress of the complexity of heart period and systolic arterial pressure variability, which are related to the different role played by LRC in the two conditions.

In this work, we report on a comparison among graphene field-effect transistors (GFETs) employing different dielectrics as gate layers to evaluate their microwave response. In particular, aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), and hafnium oxide (HfO 2 ) have been tested. GFETs have been fabricated on a single chip and a statistical analysis has been performed on a set of 24 devices for each type of oxide. Direct current and microwave measurements have been carried out on such GFETs and short circuit current gain and maximum available gain have been chosen as quality factors to evaluate their microwave performance. Our results show that all of the devices belonging to a specific group (i.e., with the same oxide) have a well-defined performance curve and that the choice of hafnium oxide represents the best trade-off in terms of dielectric properties. Graphene transistors employing HfO 2 as the dielectric layer, in fact, exhibit the best performance in terms of both the cutoff frequency and the maximum frequency of oscillation., Competing Interests: The authors declare no competing financial interest.

The gold standard method to monitor heart rate variability (HRV) comprises measuring the time series of interbeat interval durations from electrocardiographic (ECG) recordings. However, due to the widespread use, simplicity and usability of photoplethysmographic (PPG) techniques, monitoring pulse rate variability (PRV) from pulse wave recordings has become a viable alternative to standard HRV analysis. The present study investigates the accuracy of PRV, measured as a surrogate of HRV, for the quantification of descriptive indexes computed in the time domain (mean, variance), frequency domain (low-to-high frequency power ratio LF/HF, HF band central frequency) and information domain (entropy, conditional entropy). We analyze short time series (300 intervals) of HRV measured from the ECG and of PRV acquired from Finometer device in 76 subjects monitored in the resting supine position (SU) and in the upright position during head-up tilt (HUT). Time, frequency and information domain indexes are computed for each HRV and PRV series and, for each index, the comparison between the two approaches is performed through statistical comparison of the distributions across subjects, robust linear regression, and Bland-Altman plots. Results of the comparison indicate an overall good agreement between PRV-based and HRV-based indexes, with an accuracy that is slightly lower during HUT than during SU, and for the band-power ratio and conditional entropy. These results suggest the feasibility of PRV-based assessment of HRV descriptive indexes, and suggest to further investigate the agreement in conditions of physiological stress.

The toxicity of dietary acrylamide (AA) depends on its biotransformation pathways, in which phase I cytochrome P-450 enzymes transform AA into glycidamide. The phase II enzyme glutathione&#95;S&#95;transferase (GST) catalyses the conjugation of AA with glutathione (GSH). GST induction by phytochemicals like sulforaphane (SFN) plays a role in chemoprevention. Here, the effect of SFN on the detoxification of AA through GSH conjugation was studied in Caco-2 cells. GSH adducts with AA and SFN were synthesized, identified by NMR and quantified by LC-MS/MS. Caco-2 cells were treated with either 2.5 mM AA, 10 microM SFN or the combination of both for 24 h. Concentrations of GSH conjugates (GSH-AA, GSH-SFN, SFN-GSH-AA), AA and SFN were analysed by LC-MS/MS. GSH contents and GST activity were determined photometrically. GST activity was increased after treatment of the cells with SFN (38+/-6%, p< or =0.05) or AA (25+/-4%, p< or =0.05). GSH concentrations decreased after all treatments. Quantitative data of GSH adduct formation showed that the reaction between GSH and SFN is favoured over that between GSH and AA. The data suggest that SFN might impair the GSH-dependent detoxification of AA by SFN-GSH adduct formation and, thus, lower the GSH concentrations available for its reaction with AA.

A number of international studies have highlighted family caregivers' (FCGs') dissatisfaction with their relationship with mental health professionals (MHPs) when providing care for mentally ill family members. However, few studies have explored the mental health professionals' perspective of this relationship. This study explored both FCGs' and MHPs' perspectives. Semi-structured interviews were conducted with seven FCGs and seven MHPs from two different geographical areas of New Zealand. Thematic analysis of these interviews revealed four distinct MHP themes and five FCG themes. The themes illuminate incongruence between MHPs' intentions to form a positive working relationship with families and the FCGs' mainly negative experiences of this relationship.

Aims: To report findings on employment, duration of residence and mental health from a longitudinal study of 107 skilled immigrants to New Zealand from the People's Republic of China, India and South Africa., Methods: Demographic and employment data were collected by face-to-face interviews using a structured questionnaire that included (as the mental health instrument) the General Health Questionnaire 12 (GHQ-12). The initial interview took place after the immigrants had been resident in New Zealand for an average of five months. Four subsequent interviews were conducted annually (1999-2002) on or about the anniversary of the first interview., Results and Conclusion: Rather than an initial euphoric period followed by a mental health crisis, the results indicated poor mental health status in the first two years irrespective of employment status. Thereafter, mental health slightly improved as did employment rates. A surprising result was that although the South Africans had the highest employment rate, there were neither substantial mental health differences among the three groups nor was there a significant improvement during the course of the longitudinal study.

Two pigmented wheat genotypes (blue and purple) and two black barley genotypes were fractionated in bran and flour fractions, examined, and compared for their free radical scavenging properties against 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (Trolox equivalent antioxidant capacity, TEAC), ferric reducing antioxidant power (FRAP), total phenolic content (TPC), phenolic acid composition, carotenoid composition, and total anthocyanin content. The results showed that fractionation has a significant influence on the antioxidant properties, TPC, anthocyanin and carotenoid contents, and phenolic acid composition. Bran fractions had the greatest antioxidant activities (1.9-2.3 mmol TEAC/100 g) in all four grain genotypes and were 3-5-fold higher than the respective flour fractions (0.4-0.7 mmol TEAC/100 g). Ferulic acid was the predominant phenolic acid in wheat genotypes (bran fractions) while p-coumaric acid was the predominant phenolic acid in the bran fractions of barley genotypes. High-performance liquid chromatography analysis detected the presence of lutein and zeaxanthin in all fractions with different distribution patterns within the genotypes. The highest contents of anthocyanins were found in the middlings of black barley genotypes or in the shorts of blue and purple wheat. These data suggest the possibility to improve the antioxidant release from cereal-based food through selection of postharvest treatments.

Regular consumption of tomatoes has been associated with decreased risk of chronic degenerative diseases. Epidemiological findings confirm the observed health effects are due to the presence of different antioxidant molecules such as carotenoids, particularly lycopene, ascorbic acid, vitamin E and phenol compounds, particularly flavonoids. In this work, eight components contributing to the healthy quality of tomato (i. e. lycopene, beta-carotene, other carotenoids, flavonoids, phenolic acids, vitamins C and E, dry residue) were studied in the framework of breeding programs aiming to develop nutritional superior genotypes. Twelve tomato advanced breeding lines and six open pollinated cultivars were grown in strictly controlled conditions and analysed for their content of antioxidants. Among the 18 genotypes analysed, 10 showed a high level of total carotenoids, 6 high level of beta-carotene, 9 high lycopene levels, 15 high flavonoids and 2 relevant concentration of vitamin E. Based on such data and on a literature survey on tomato composition, an index, called index of antioxidant nutritional quality (I(QUAN)), was proposed as a tool to address the breeding programs in selecting tomato genotypes with antioxidant nutritional qualities.

In earlier experiments, the MDR (multidrug resistance)-reversal activities of Anastasia Black (Russian black sweet pepper) extracts had been analysed. Recently, the most effective MDR reversing extracts and fractions have been separated by HPLC (high-performance liquid chromatography, for carotenoids) and LC-MS-MS (HPLC combined with mass spectrometry, for phenolic compounds) methods. As a result of the analytical studies, the following flavonoids had been identified: feruloyl glucopyranoside, quercetin rhamnopyranoside glucopyranoside, luteolin glucopyranoside arabinopyranoside, apigenin glucopyranoside arabinopyranoside, quercetin rhamnopyranoside, luteolin arabinopyranoside diglucopy-ranoside, hesperidine and luteolin glucuronide. According to the literature, the aglycones of these phenolic compounds exhibit MDR-reversal activity in vitro, and the connection between the phenolic content of Anastasia Black and MDR-reversal action was therefore studied by different analytical methods. The results of this study revealed that the identified flavonoids of Anastasia Black may be only partially responsible for the modulation of the MDR of mouse lymphoma cells. Other lipophilic compounds, most probably carotenoids, present in Russian black sweet pepper may act as inhibitors of MDR reversal.

Several demographic and post-immigration factors related to self-reported symptoms of anxiety and depression of immigrants in New Zealand were examined in a study involving a sample of 129 Southeast Asian refugees, 57 Pacific Island immigrants, and 63 British immigrants to New Zealand. A questionnaire and the Hopkins Symptom Checklist-25 (HSCL-25) in English and in three Southeast Asian translations were administered, followed by an interview in English or with an interpreter. The findings suggest that demographic characteristics are not associated with symptom level. Post-immigration factors, such as experiencing discrimination in New Zealand, not having close friends, being unemployed, and spending most of one's time with one's own ethnic group affected anxiety and depression scores.

Sluzki's 1986 mental health model of the migratory process was tested with migrants (both refugees and immigrants), to New Zealand. Its central feature, suggesting an initial symptom free and euphoric phase after arrival in the country of settlement, followed by a crisis stage, was examined for 129 Southeast Asian refugees, 57 Pacific Island immigrants and 63 British immigrants. A questionnaire and the Hopkins Symptom Checklist-25, in English and in three Southeast Asian language translations, were administered face-to-face. All respondents had arrived in New Zealand within the last 15 years. The findings did not support Sluzki's model. Refugees and immigrants in the group with less than six months of residence were not symptom free. Neither did the group with six months to six years residence demonstrate a deterioration in mental health. However, mean depression levels were slightly lower for those who had lived in New Zealand for over six years, suggesting that mental health may improve the longer both refugees and immigrants reside in the host country.

This study investigated and compared mental health levels among refugees and immigrants living in New Zealand. One hundred and twenty-nine Indochinese refugees, 57 Pacific Island immigrants and 63 British immigrants to New Zealand were surveyed. A questionnaire and the Hopkins Symptom Checklist-25 (HSCL-25) in English and in three Indochinese translations, were administered face-to-face. The hypothesis that migrant status (being a refugee or immigrant) affects mental health and that refugees experience more emotional distress than immigrants was only supported by the comparison with British immigrants. Both Indochinese refugees and Pacific Island immigrants experienced relatively low levels of mental health. However, the incidence of clinical depression and clinical total emotional distress tended to be higher among Indochinese refugees than in either immigrant group. In contrast clinical anxiety occurred most often among Pacific Islanders.