2,418 research outputs found

    Generalized Q Models for Investment

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    We extend the Q theory of investment to allow for adjustment costs for labor, under the additional assumption that the firm is a monopolistic competitor in the output market. The issue of nonconstant returns to scale is also discussed. We show that the standard Q model is a special case of a more general model involving testable parameter restrictions. Estimates for the U.S. manufacturing sector suggest that the departure from the assumption of perfect competition and lack of adjustment costs for labor receive empirical support in the data

    Toleration as the Balance between Liberty and Security

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    Traditionally, an adequate strategy to deal with the tension between liberty and security has been toleration, for the latter allows the maximization of individual liberty without endangering security, since it embraces the limits set by the harm principle and the principle of self-defense of the liberal order. The area outside the boundary clearly requires repressive measures to protect the security and the rights of all. In this paper, we focus on the balance of liberty and security aforded by toleration, analyzing how this strategy works in highly confictual contexts and sorting out the diferent sets of reason that might motivate individual to assume a tolerant attitude. We contend that toleration represents a reliable political solution to conficts potentially threatening social security when it is coupled with social tolerance. Hence, we examine the reasons the agents may have for endorsing toleration despite disagreement and disapproval. In the range of these reasons, we argue that the right reasons are those preserving the moral and epistemic integrity of the agent. The right reasons are however not accessible to everyone, as for example is the case with (nonviolent) religious fundamentalists. Only prudential reasons for toleration seem to be available to them. And yet, we argue that an open and inclusive democracy should in principle be hospitable towards prudential and pragmatic reasons as well, which may potentially lay the grounds for future cooperation. We conclude therefore that the tolerant society has room for the fundamentalists, granted that they do not resort to violence

    Recent advances in analytical approaches for the standardization and quality of polyphenols of propolis

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    Analytical approaches utilized for the characterization of polyphenols from propolis useful for the determination of its quality is investigated in this study. A qualitative and quantitative evaluation of propolis bioactive molecules is of interest in medicine and nutraceuticals. Recent powerful analytical techniques are of great utility to separate and quantify polyphenols in extracts and finished products due to their capacity to produce typical fingerprints and a reliable identification of many components. According to this, an HPLC-UV-MS procedure was validated and applied for the characterization and quantification of bioactive substances in propolis and for an accurate assessment of their content in extract samples. By using this analytical approach, we obtained specific compositions related to brown propolis acquired from different geographic areas (and preparations and treatment). This is more important by considering the scientific opinion of European Food Safety Authority (EFSA) which provided a negative response related to health claims of propolis and its polyphenols. These results prove that HPLC-MS is an attractive tool for the standardization and quality control of propolis and may be realistically applied to screen raw material and to evaluate finished commercial preparations and nutraceutical benefits

    Chemical Composition and Antioxidant Activity of Propolis Prepared in Different Forms and in Different Solvents Useful for Finished Products

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    Different products from a unique propolis extract obtained by using various solvents such as hydroalcoholic, glycolic (98% propylene glycol), and glyceric solutions, and oil, as well as in powder form, named ESIT12, were prepared. The molecular composition of the different preparations was evaluated and their antioxidant activity determined. All the preparations showed a quite similar polyphenol composition and comparable percentage even if ESIT12 was found to be richer in phenolic acids (caffeic, coumaric, ferulic, and isoferulic). Overall, flavones and flavonols ranged from ~20% up to ~36% in the glyceric extract, while flavanones and diidroflavonols were between ~28% and ~41%. Besides their quite similar composition, glycolic and hydroalcoholic extracts were found to be richer in the total polyphenols content. When the antioxidant properties were determined for the four preparations, the activity was similar among them, thus revealing that it is strictly related to the polyphenols content for propolis products whose composition is quite comparable. To date, very few data are available on propolis composition in glyceric and glycolic extracts and information has never been published on propolis in oil. This study could be of interest to the food and nutraceutical industries to choose suitable solvents and conditions to produce propolis preparations useful for active finished products

    Lavender (Lavandula angustifolia Mill.) Essential Oil Alleviates Neuropathic Pain in Mice With Spared Nerve Injury

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    Low treatment efficacy represents an important unmet need in neuropathic pain patients and there is an urgent need to develop a more effective pharmacotherapy. An increasing number of patients choose complementary medicine to relieve pain. Lavender essential oil (LEO) is approved by the European Medicines Agency as herbal medicine to relieve anxiety and stress. However, the capability of LEO to relieve other nervous system disorders such as neuropathic pain has never been established. Our work aimed to evaluate the antineuropathic properties of lavender on a spared nerve injury (SNI) model of neuropathic pain in mice. An acute oral administration of LEO (100 mg/kg) alleviated SNI-induced mechanical allodynia, evaluated in the von Frey test, with an intensity comparable to the reference drug pregabalin. Investigations into the mechanism of action showed that LEO markedly decreased the phosphorylation of ERK1, ERK2, and JNK1, and decreased the levels of iNOS in the spinal cord; involvement of the endocannabinoid system was also detected using in vitro inhibition of the FAAH and MALG enzymes as well as in vivo experiments with the CB1 antagonist. Conversely, no effect on P38 phosphorylation and NF-kB activation was detected. These antihyperalgesic effects appeared at the same dose able to induce antidepressant-like, anxiolytic-like, and anorexic effects. In addition, gavage with LEO did not significantly alter animals'' gross behavior, motor coordination, or locomotor activity, nor impaired memory functions. Oral administration of LEO could represent a therapeutic approach in the management of neuropathic pain states

    Attenuation of anxiety-like behavior by helichrysum stoechas (L.) moench methanolic extract through up-regulation of erk signaling pathways in noradrenergic neurons

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    The long-term use of anxiolytic and antidepressant drugs can cause a plethora of side effects and the use of complementary and alternative medicine, which is generally considered safer than conventional medicine, is consistently increasing. Helichrysum stoechas (L.) Moench methanolic extract (HSE) has shown MAO-A inhibitory properties in previous studies. With the aim of obtaining innovative and safer therapies for mood disorders, this study investigated the potential activity of HSE in the management of anxiety-and depression-related symptoms. HSE showed dose-dependent (30–100 mg/kg p.o.) anxiolytic-like activity in the light dark box and marble burying tests, without any antidepressant-like activity, as shown by the results of the tail suspension test. Additionally, HSE did not have any effect on the modulation of pain, which highlights its selectivity in the control of anxiety-related behavior. At active doses, HSE did not produce any sedative effect or result in impaired motor coordination and memory functions. Western blotting experiments showed the ability of HSE to counteract the reduction in the phosphorylation of ERK44/42, to restore brain-derived neurotrophic factor (BDNF) expression and to return cyclic AMP response element binding (CREB) levels to basal levels in noradrenergic hippocampal neurons of mice exposed to an anxiety-related environment, which indicates a protective role against anxiety behavior. These results suggest that oral administration of HSE might represent an interesting opportunity for the management of anxiety disorders

    PURIFICATION OF PROPOLIS FROM POLYCYCLIC AROMATIC HYDROCARBONS AND PRESERVATION OF ACTIVE POLYPHENOL COMPONENT.

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    Organic pollutants have become an increasing concern due to their potential of mutagenicity, carcinogenicity, teratogenicity and high bioaccumulation. The adverse effects on health and environment caused by specific organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) have been considered as critical problems. The European Food Safety Authority (EFSA) has defined 16 priority PAH that are both genotoxic and carcinogenic and identified eight (PAH8) or four (PAH4) priority PAH as good indicators of the toxicity and occurrence of PAH in food. Several available techniques (photocatalytic degradation, combined photo-fenton and ultrasound, advanced oxidation, aerobic degradation, filtration, ozonation, coagulation, flocculation, distillation, extraction, precipitation, and adsorption, etc.) have been developed for PAH removal. Food supplements containing propolis were also found to show relatively high PAHs. As a consequence, a main goal is to adopt purification procedures to remove PAH from propolis and preserve its polyphenol components before its use in finished products. Here we report an extractive procedure (M.E.D., Multi Dynamic Extraction) able to purify propolis from a great content of PAH by using a balanced mixture of organic and water solvents. Obtained propolis extracts are still rich in polyphenols and glycosylated derivatives showing PAH8 and specific benzo[a]pyrene content below limits recommended by EFSA

    Trigeminal sensory pathway function in patients with SUNCT

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    [IF 2.64] Objective: Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) is a rare primary headache whose origins are unclear. To seek information on its pathophysiology, we studied the trigeminal Ab and Ad pathways by recording trigeminal reflexes and laser evoked potentials (LEPs) in patients with SUNCT. Methods: Trigeminal reflexes and LEPs were recorded in 11 consecutive patients. Ten patients had neuroimaging evidence documenting idiopathic SUNCT and one had a posterior fossa tumour that compressed the trigeminal nerve thus causing symptomatic SUNCT. Results: Whereas the patients with idiopathic SUNCT had normal trigeminal reflex and LEP responses, the patient with symptomatic SUNCT had abnormal responses. Conclusions: Our neurophysiological findings show that idiopathic SUNCT spares the trigeminal sensory pathways whereas symptomatic SUNCT does not. Significance: Neurophysiological testing can easily differentiate the idiopathic and symptomatic forms of SUNCT. It also suggests that the two forms are pathophysiologically distinct entities

    Analysis of normal levels of free glycosaminoglycans in urine and plasma in adults

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    Plasma and urine glycosaminoglycans (GAGs) are long, linear sulfated polysaccharides that have been proposed as potential noninvasive biomarkers for several diseases. However, owing to the analytical complexity associated with the measurement of GAG concentration and disaccharide composition (the so-called GAGome), a reference study of the normal healthy GAGome is currently missing. Here, we prospectively enrolled 308 healthy adults and analyzed their free GAGomes in urine and plasma using a standardized ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry method together with comprehensive demographic and blood chemistry biomarker data. Of 25 blood chemistry biomarkers, we mainly observed weak correlations between the free GAGome and creatinine in urine and hemoglobin or erythrocyte counts in plasma. We found a higher free GAGome concentration - but not a more diverse composition - in males. Partitioned by gender, we also established reference intervals for all detectable free GAGome features in urine and plasma. Finally, we carried out a transference analysis in healthy individuals from two distinct geographical sites, including data from the Lifelines Cohort Study, which validated the reference intervals in urine. Our study is the first large-scale determination of normal free GAGomes reference intervals in plasma and urine and represents a critical resource for future physiology and biomarker research
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