Linear correlation between fractal dimension of EEG signal and handgrip force

Fractal dimension (FD) has been proved useful in quantifying the complexity of dynamical signals in biology and medicine. In this study, we measured FDs of human electroencephalographic (EEG) signals at different levels of handgrip forces. EEG signals were recorded from five major motor-related cortical areas in eight normal healthy subjects. FDs were calculated using three different methods. The three physiological periods of handgrip (command preparation, movement and holding periods) were analyzed and compared. The results showed that FDs of the EEG signals during the movement and holding periods increased linearly with handgrip force, whereas FD during the preparation period had no correlation with force. The results also demonstrated that one method (Katz’s) gave greater changes in FD, and thus, had more power in capturing the dynamic changes in the signal. The linear increase of FD, together with results from other EEG and neuroimaging studies, suggest that under normal conditions the brain recruits motor neurons at a linear progress when increasing the force.     

Primary care and abortion legislation in Chile: A failed point of entry

While Chile's partial decriminalization of abortion in 2017 was a long overdue recognition of women's sexual and reproductive rights, nearly four years later the caseload remains well below expectations. This pattern is the product of standing barriers in access to abortion-related health services, especially at the primary care point of entry. This study seeks to identify and describe these barriers. The findings presented here were obtained through a qualitative, exploratory study based on 19 semi-structured interviews with relevant actors identified through non-random sampling and snowballing techniques. Coding was inductive and complemented by semantic content analysis. The authors find that the key barriers in primary care to accessing legal abortion are unfamiliarity with the law, insufficient practitioner training, intersectoral discrimination, and the stigma surrounding abortion. They conclude that the government needs to exercise its constitutional mandate as guarantor of public health and act promptly to safeguard and guarantee the abortion rights of Chilean women.     

EMG signal amplitude normalization technique in stretch-shortening cycle movements

Analysis of functional movements using surface electromyography (EMG) often involves recording both eccentric and concentric muscle activity during a stretch-shorten cycle (SSC). The techniques used for amplitude normalization are varied and are independent of the type of muscle activity involved. The purpose of this study was: (i) to determine the effect of 11 amplitude normalization techniques on the coefficient of variation (CV) during the eccentric and concentric phases of the SSC; and (ii) to establish the effect of the normalization techniques on the EMG signal under variable load and velocity. The EMG signal of the biceps brachii of eight normal subjects was recorded under four SSC conditions and three levels of isometric contraction. The 11 derived normalization values were total rms, mean rms and peak rms (100 ms time constant) for the isometric contractions and the mean rms and peak rms values of the ensemble values for each set of isotonic contractions. Normalization using maximal voluntary isometric contractions (MVIC), irrespective of rms processing (total, mean or peak), demonstrated greater CV above the raw data for both muscle actions. Mean ensemble values and submaximal isometric recordings reduced the CV of concentric data. No amplitude normalization technique reduced the CV for eccentric data under loaded conditions. An ANOVA demonstrated significant (P < 0.01) main effects for load and velocity on concentric raw data and an interaction (P < 0.05) for raw eccentric data. No significant effects were demonstrated for changes in velocity when the data were normalized using mean rms values. The reduction of the CV should not be at the expense of true biological variance and current normalization techniques poorly serve the analysis of eccentric muscle activity during the SSC.     

Ventilatory conditioning by self-stimulation in rats: A pilot study

This article describes an experimental attempt to condition breathing pattern in rats. In this experiment, a freely moving rat was first rewarded by an electrical stimulation of the medial forebrain bundle whenever inspiratory duration (TI) exceeded 300 ms. A bidirectional control was then used: TIs longer than 400 ms were rewarded, and then TIs shorter than 300 ms were rewarded. The frequency of TIs longer than 300 ms increased when this event was rewarded, further increased when TIs above 400 ms were rewarded, and decreased during reversal conditioning (TI < 300 ms). At the beginning of the experiment, stimulation caused increased arousal and motor activity, but after prolonged conditioning, the brain stimulation was associated with quiet wakefulness. Although the general procedure appears to be well-suited to the experimental study of voluntary breathing, some possible improvements are suggested for further, more extensive investigations.We are grateful to Professor Claude Gaultier and to Professor Vincent Bloch for their support, to Pascale Leblanc for her invaluable assistance, and to Gerard Dutrieux and Michel Vigouroux for their technical contribution. This work was supported by the Université de Paris-Sud (Grant AI-9023) and by the Institut National de la Sante et de la Recherche Médicale (CJF 89-09).     

Talking with the Donkey: Cooperative Approaches to Environmental Protection

In recent years, governments throughout the world have expressed growing interest in cooperative approaches to environmental protection, including negotiated rulemaking, flexible approaches t o enforcement, and voluntary codes and agreements. It is often argued that cooperative approaches are more cost effective, more conducive t o innovation, and better able t o promote fundamental attitudinal change than traditional "command and control" regulation. However, the overly broad term "cooperative approaches" fails t o acknowledge fundamental differences among these novel po I icies, including distinct ions between mandatory and voluntary programs and between those that involve bipartite negotiations between government and business and those that invite participation by a broader range of interests. This article analyzes these cooperative approaches first by offering a framework to distinguish among various cooperative policy instruments. Second, the article critically examines theoretical arguments and empirical evidence concerning one class o f cooperative approaches, voluntary challenges and agreements. The most striking finding is how little we know about the effectiveness of voluntary approaches. This is a function not only of the quite recent experience with these approaches, but also of more fundamental inattention t o program evaluation and obstacles to evaluation inherent in voluntary programs. The article concludes with a call for a more rigorous program of research to examine the effectiveness of the new policy instruments and t o compare them with traditional regulation and market-based incentives.     

Synthesis of 6-deoxy-5-thio- -glucose

Three routes were investigated for the conversion of -glucose into the title compound. In the first approach, reduction of the 5,6-thürane ring of 5,6-dideoxy-5,6-epithio-1,2-O-isopropylidene α- -glucofuranose (17) as well as that of its 3-O-allyl derivative (13) with lithium aluminium hydride was investigated; 17 afforded the corresponding 6-deoxy derivative besides di-, tri-, and poly-mers, whereas only polymers were formed from 13. In the second approach, the oxirane ring of

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was reduced by sodium borohydride and the resulting 6-deoxy derivative was converted into the 5-thiobenzoate; the corresponding hex-4-enofuranose was formed as a byproduct. In the third approach partial mesylation of methyl 5-thio-α- -glucopyranoside was attempted, but the 6-mesylate 27 could be isolated only in modest yield (28%) together with rearranged 2,5-thioanhydromannofuranoside derivatives. The mechanism of this rearrangement is discussed in detail. The 6-mesylate 27 was converted via the 6-iodo derivative into the title compound.     

Torque-onset determination: Unintended consequences of the threshold method

Background: Compared with visual torque-onset-detection (TOD), threshold-based TOD produces onset bias, which increases with lower torques or rates of torque development (RTD). Purpose: To compare the effects of differential TOD-bias on common contractile parameters in two torque-disparate groups. Methods: Fifteen boys and 12 men performed maximal, explosive, isometric knee-extensions. Torque and EMG were recorded for each contraction. Best contractions were selected by peak torque (MVC) and peak RTD. Visual-TOD-based torque-time traces, electromechanical delays (EMD), and times to peak RTD (tRTD) were compared with corresponding data derived from fixed 4-N m- and relative 5%MVC-thresholds. Results: The 5%MVC TOD-biases were similar for boys and men, but the corresponding 4-N m-based biases were markedly different (40.3 ± 14.1 vs. 18.4 ± 7.1 ms, respectively; p < 0.001). Boys–men EMD differences were most affected, increasing from 5.0 ms (visual) to 26.9 ms (4 N m; p < 0.01). Men’s visually-based torque kinetics tended to be faster than the boys’ (NS), but the 4-N m-based kinetics erroneously depicted the boys as being much faster to any given %MVC (p < 0.001). Conclusions: When comparing contractile properties of dissimilar groups, e.g., children vs. adults, threshold-based TOD methods can misrepresent reality and lead to erroneous conclusions. Relative-thresholds (e.g., 5% MVC) still introduce error, but group-comparisons are not confounded.     

Voluntary exercise increases IgA concentration and polymeric Ig receptor expression in the rat submandibular gland

Salivary IgA—a primary factor in local immunity of the oral cavity—plays an important role in maintaining local immune function in the oral cavity and prevent upper respiratory tract infections. Oral IgA levels are known to fluctuate in an exercise-dependent manner; thus, we investigated the effects of voluntary exercise on salivary IgA secretion in rats to better understand the mechanism by which this occurs. Six-week-old male Wistar rats were placed in individual cages with or without access to exercise wheels for three weeks. Notably, animals who engaged in voluntary exercise demonstrated significant increases in IgA concentration in saliva and submandibular gland tissue, as well as a markedly higher salivary IgA flow rate. Moreover, active rats also exhibited elevated polymeric Ig receptor (pIgR) mRNA expression in submandibular gland tissue. Collectively, these results suggest that voluntary exercise may increase salivary IgA concentration and boost immune function in the oral cavity.     

Ethnic and immigrant politics vs. mainstream politics: the role of ethnic organizations in shaping the political participation of immigrant-origin individuals in Europe

Previous scholarship has reported contradictory results regarding the impact of involvement by immigrant-origin individuals (IOIs) in ethnic organizations on political participation. In this article, we assess the effect of involvement in different types of organizations (ethnic, pan-immigrant and native) on participation in various types of political activities. We use cross-national micro-data from a population survey undertaken in 2004–2008 to IOIs in nine European cities. Our findings indicate that ethnic organizations perform an integrative function for IOIs in the political sphere, but they mainly affect participation linked to immigration-related issues concerning specific ethnic groups and IOIs. Moreover, most effects of involvement in ethnic organizations on the different types of political participation examined are similar in closed and in open political opportunity structures (POS). We only find evidence that involvement in ethnic organizations depresses conventional political action in open POS settings while it increases political action in closed POS settings.     

Mobilising mosques? The role of service attendance for political participation of Turkish and Moroccan minorities in the Netherlands

Religious service attendance has been identified as an important source of political participation among Christians and Muslims in the USA. In Europe, where religion is seen as a barrier rather than a bridge to Muslims’ integration, the role of mosque attendance for the political participation of Muslims remains understudied. This study asks whether the politically mobilizing role of service attendance extends to Muslim minorities in Europe. We examine direct and indirect effects of the frequency of religious service attendance on organizational participation, political trust and voting intentions among large nationwide samples of Turkish and Moroccan minorities in the Netherlands using multi-group structural equation modelling. Our results show that service attendance relates positively to engagement in both co-ethnic and mainstream organizations. These two forms of civic engagement translate into a greater intention to vote among Turks, but not Moroccans.