932 resultados para Defense and Security Studies
Resumo:
In a post-Cold War, post-9/11 world, the advent of US global supremacy resulted in the installation, perpetuation, and dissemination of an Absolutist Security Agenda (hereinafter, ASA). The US ASA explicitly and aggressively articulates and equates US national security interests with the security of all states in the international system, and replaced the bipolar, Cold War framework that defined international affairs from 1945-1992. Since the collapse of the USSR and the 11 September 2001 terrorist attacks, the US has unilaterally defined, implemented, and managed systemic security policy. The US ASA is indicative of a systemic category of knowledge (security) anchored in variegated conceptual and material components, such as morality, philosophy, and political rubrics. The US ASA is based on a logic that involves the following security components: 1., hyper militarization, 2., intimidation, 3., coercion, 4., criminalization, 5., panoptic surveillance, 6., plenary security measures, and 7., unabashed US interference in the domestic affairs of select states. Such interference has produced destabilizing tensions and conflicts that have, in turn, produced resistance, revolutions, proliferation, cults of personality, and militarization. This is the case because the US ASA rests on the notion that the international system of states is an extension, instrument of US power, rather than a system and/or society of states comprised of functionally sovereign entities. To analyze the US ASA, this study utilizes: 1., official government statements, legal doctrines, treaties, and policies pertaining to US foreign policy; 2., militarization rationales, budgets, and expenditures; and 3., case studies of rogue states. The data used in this study are drawn from information that is publicly available (academic journals, think-tank publications, government publications, and information provided by international organizations). The data supports the contention that global security is effectuated via a discrete set of hegemonic/imperialistic US values and interests, finding empirical expression in legal acts (USA Patriot ACT 2001) and the concept of rogue states. Rogue states, therefore, provide test cases to clarify the breadth, depth, and consequentialness of the US ASA in world affairs vis-a-vis the relationship between US security and global security.
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The proliferation of weapons of mass destruction (WMD), nuclear, biological and chemical (NBC) is one of the main security challenges facing the international community today. However the new Global Security Strategy of 2016 raises the question of non-proliferation of WMD only as an incidental matter, not addressing directly the threat, a fundamental threat in the regional and global security. This is a clear step backwards for the European common security.
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The present thesis describes the development of heterogeneous catalytic methodologies using metal−organic frameworks (MOFs) as porous matrices for supporting transition metal catalysts. A wide spectrum of chemical reactions is covered. Following the introductory section (Chapter 1), the results are divided between one descriptive part (Chapter 2) and four experimental parts (Chapters 3–6). Chapter 2 provides a detailed account of MOFs and their role in heterogeneous catalysis. Specific synthesis methods and characterization techniques that may be unfamiliar to organic chemists are illustrated based on examples from this work. Pd-catalyzed heterogeneous C−C coupling and C−H functionalization reactions are studied in Chapter 3, with focus on their practical utility. A vast functional group tolerance is reported, allowing access to substrates of relevance for the pharmaceutical industry. Issues concerning the recyclability of MOF-supported catalysts, leaching and operation under continuous flow are discussed in detail. The following chapter explores puzzling questions regarding the nature of the catalytically active species and the pathways of deactivation for Pd@MOF catalysts. These questions are addressed through detailed mechanistic investigations which include in situ XRD and XAS data acquisition. For this purpose a custom reaction cell is also described in Chapter 4. The scope of Pd@MOF-catalyzed reactions is expanded in Chapter 5. A strategy for boosting the thermal and chemical robustness of MOF crystals is presented. Pd@MOF catalysts are coated with a protecting SiO2 layer, which improves their mechanical properties without impeding diffusion. The resulting nanocomposite is better suited to withstand the harsh conditions of aerobic oxidation reactions. In this chapter, the influence of the nanoparticles’ geometry over the catalyst’s selectivity is also investigated. While Chapters 3–5 dealt with Pd-catalyzed processes, Chapter 6 introduces hybrid materials based on first-row transition metals. Their reactivity is explored towards light-driven water splitting. The heterogenization process leads to stabilized active sites, facilitating the spectroscopic probing of intermediates in the catalytic cycle.
Resumo:
Synthetic cannabinoid receptor agonists or more commonly known as synthetic cannabinoids (SCs) were originally created to obtain the medicinal value of THC but they are an emerging social problem. SCs are mostly produced coated on herbal materials or in powder form and marketed under a variety of brand names, e.g. “Spice”, “K2”. Despite many SCs becoming controlled under drug legislation, many of them remain legal in some countries around the world. In Scotland, SCs are controlled under the Misuse of Drugs Act 1971 and Psychoactive Substances Act 2016 that only cover a few early SCs. In Saudi Arabia, even fewer are controlled. The picture of the SCs-problem in Scotland is vague due to insufficient prevalence data, particularly that using biological samples. Whilst there is evidence of increasing use of SCs throughout the world, in Saudi Arabia, there is currently no data regarding the use of products containing SCs among Saudi people. Several studies indicate that SCs may cause serious toxicity and impairment to health therefore it is important to understand the scale of use within society. A simple and sensitive method was developed for the simultaneous analysis of 10 parent SCs (JWH-018, JWH-073, JWH-250, JWH-200, AM-1248, UR-144, A-796260, AB-FUBINACA, 5F-AKB-48 and 5F-PB-22) in whole blood and 8 corresponding metabolites (JWH-018 4-OH pentyl, JWH-073 3-OH butyl, JWH-250 4-OH pentyl, AM-2201 4-OH pentyl, JWH-122 5-OH pentyl, JWH-210 5-OH pentyl, 5F-AKB-48 (N-4 OH pentyl), 5F-PB-22 3-carboxyindole)in urine using LLE and LC-MS/MS. The method was validated according to the standard practices for method validation in forensic toxicology (SWGTOX, May 2013). All analytes gave acceptable precision, linearity and recovery for analysing blood and urine samples. The method was applied to 1,496 biological samples, a mixture of whole blood and urine. Blood and/or urine samples were analysed from 114 patients presenting at Accident and Emergency in Glasgow Royal Infirmary, in spring 2014 and JuneDecember 2015. 5F-AKB-48, 5F-PB-22 and MDMB-CHMICA were detected in 9, 7 and 9 cases respectively. 904 urine samples from individuals admitted to/liberated from Scottish prisons over November 2013 were tested for the presence of SCs. 5F-AKB-48 (N-4 OH pentyl) was detected in 10 cases and 5F-PB-22 3-carboxyindole in 3 cases. Blood and urine samples from two post-mortem cases in Scotland with suspected ingestion of SCs were analysed. Both cases were confirmed positive for 5F-AKB-48. A total of 463 urine samples were collected from personnel who presented to the Security Forces Hospital in Ryiadh for workplace drug testing as a requirement for their job during July 2014. The results of the analysis found 2 samples to be positive for 5F-PB-22 3carboxyindole. A further study in Saudi Arabia using a questionnaire was carried out among 3 subpopulations: medical professionals, members of the public in and around smoking cafes and known drug users. With regards to general awareness of Spice products, 16%, 11% and 22% of those participants of medical professionals, members of the public in and around smoking cafes and known drug users, respectively, were aware of the existence of SCs or Spice products. The respondents had an overall average of 4.5% who had a friend who used these Spice products. It is clear from the results obtained in both blood and urine testing and surveys that SCs are being used in both Scotland and Saudi Arabia. The extent of their use is not clear and the data presented here is an initial look into their prevalence. Blood and urine findings suggest changing trends in SC use, moving away from JWH and AM SCs to the newer 5F-AKB-48, 5-F-PB-22 and MDMBCHMICA compounds worldwide. In both countries 5F-PB-22 was detected. These findings clarify how the SCs phenomenon is a worldwide problem and how the information of every country regarding what SCs are seized can help and is not specific for that country. The analytes included in the method were selected due to their apparent availability in both countries, however it is possible that some newer analytes have been used and these would not have been detected. For this reason it is important that methods for testing SCs are updated regularly and evolve with the ever-changing availability of these drugs worldwide. In addition, there is little published literature regarding the concentrations of these drugs found in blood and urine samples and this work goes some way towards understanding these.
Resumo:
The aim of this special issue is to widen the existing debates on security privatization by looking at how and why an increasing number of private actors beyond private military and/or security companies (PMSCs) have come to perform various security related functions. While PMSCs produce security for profit, most other private sector actors make profit by selling goods and services that were originally not connected with security in the traditional understanding of the term. However, due to the continuous introduction of new legal and technical regulations by public authorities, many non- security related private businesses nowadays have to perform at least some security functions. Little research, however, has been done thus far, both in terms of security practices of non- security related private businesses and their impact on security governance. This introduction explains how this special issue contributes to closing this glaring gap by 1) extending the conceptual and theoretical arguments in the existing body of literature; and 2) offering a range of original case studies on the specific roles of non- security related private companies of all sizes, areas of businesses, and geographic origin.
Resumo:
Historical evidence shows that chemical, process, and Oil&Gas facilities where dangerous substances are stored or handled are target of deliberate malicious attacks (security attacks) aiming at interfering with normal operations. Physical attacks and cyber-attacks may generate events with consequences on people, property, and the surrounding environment that are comparable to those of major accidents caused by safety-related causes. The security aspects of these facilities are commonly addressed using Security Vulnerability/Risk Assessment (SVA/SRA) methodologies. Most of these methodologies are semi-quantitative and non-systematic approaches that strongly rely on expert judgment, leading to security assessments that are not reproducible. Moreover, they do not consider the synergies with the safety domain. The present 3-year research is aimed at filling the gap outlined by providing knowledge on security attacks, as well as rigorous and systematic methods supporting existing SVA/SRA studies suitable for the chemical, process, and Oil&Gas industry. The different nature of cyber and physical attacks resulted in the development of different methods for the two domains. The first part of the research was devoted to the development and statistical analysis of security databases that allowed to develop new knowledge and lessons learnt on security threats. Based on the obtained background, a Bow-Tie based procedure and two reverse-HazOp based methodologies were developed as hazard identification approaches for physical and cyber threats respectively. To support the quantitative estimation of the security risk, a quantitative procedure based on the Bayesian Network was developed allowing to calculate the probability of success of physical security attacks. All the developed methods have been applied to case studies addressing chemical, process and Oil&Gas facilities (offshore and onshore) proving the quality of the results that can be achieved in improving site security. Furthermore, the outcomes achieved allow to step forward in developing synergies and promoting integration among safety and security management.
Resumo:
Despite the ecological and economic importance of passion fruit (Passiflora spp.), molecular markers have only recently been utilized in genetic studies of this genus. In addition, both basic genetic researches related to population studies and pre-breeding programs of passion fruit remain scarce for most Passiflora species. Considering the number of Passiflora species and the increasing use of these species as a resource for ornamental, medicinal, and food purposes, the aims of this review are the following: (i) to present the current condition of the passion fruit crop; (ii) to quantify the applications and effects of using molecular markers in studies of Passiflora; (iii) to present the contributions of genetic engineering for passion fruit culture; and (iv) to discuss the progress and perspectives of this research. Thus, the present review aims to summarize and discuss the relationship between historical and current progress on the culture, breeding, and molecular genetics of passion fruit.
Resumo:
Hypobromous acid (HOBr) is an inorganic acid produced by the oxidation of the bromide anion (Br(-)). The blood plasma level of Br(-) is more than 1,000-fold lower than that of chloride anion (Cl(-)). Consequently, the endogenous production of HOBr is also lower compared to hypochlorous acid (HOCl). Nevertheless, there is much evidence of the deleterious effects of HOBr. From these data, we hypothesized that the reactivity of HOBr could be better associated with its electrophilic strength. Our hypothesis was confirmed, since HOBr was significantly more reactive than HOCl when the oxidability of the studied compounds was not relevant. For instance: anisole (HOBr, k2=2.3×10(2)M(-1)s(-1), HOCl non-reactive); dansylglycine (HOBr, k2=7.3×10(6)M(-1)s(-1), HOCl, 5.2×10(2)M(-1)s(-1)); salicylic acid (HOBr, k2=4.0×10(4)M(-1)s(-1), non-reactive); 3-hydroxybenzoic acid (HOBr, k2=5.9×10(4)M(-1)s(-1), HOCl, k2=1.1×10(1)M(-1)s(-1)); uridine (HOBr, k2=1.3×10(3)M(-1)s(-1), HOCl non-reactive). The compounds 4-bromoanisole and 5-bromouridine were identified as the products of the reactions between HOBr and anisole or uridine, respectively, i.e. typical products of electrophilic substitutions. Together, these results show that, rather than an oxidant, HOBr is a powerful electrophilic reactant. This chemical property was theoretically confirmed by measuring the positive Mulliken and ChelpG charges upon bromine and chlorine. In conclusion, the high electrophilicity of HOBr could be behind its well-established deleterious effects. We propose that HOBr is the most powerful endogenous electrophile.
Resumo:
The XX male syndrome - Testicular Disorder of Sexual Differentiation (DSD) is a rare condition characterized by a spectrum of clinical presentations, ranging from ambiguous to normal male genitalia. We report hormonal, molecular and cytogenetic evaluations of a boy presenting with this syndrome. Examination of the genitalia at age of 16 months, showed: penis of 3.5 cm, proximal hypospadia and scrotal testes. Pelvic ultrasound did not demonstrate Mullerian duct structures. Karyotype was 46,XX. Gonadotrophin stimulation test yielded insufficient testosterone production. Gonadal biopsy showed seminiferous tubules without evidence of Leydig cells. Molecular studies revealed that SRY and TSPY genes and also DYZ3 sequences were absent. In addition, the lack of deletions or duplications of SOX9, NR5A1, WNT4 and NROB1 regions was verified. The infant was heterozygous for all microsatellites at the 9p region, including DMRT1 gene, investigated. Only 10% of the patients are SRY-negative and usually they have ambiguous genitalia, as the aforementioned patient. The incomplete masculinization suggests gain of function mutation in one or more genes downstream to SRY gene.
Resumo:
We report magnetic and EPR (electron paramagnetic resonance) spectroscopy studies of [Cu2(flu)4(dmf)2] (flu = flufenamate and dmf = dimethylformamide), which has CuII ions in tetracarboxylate "paddle wheel" dinuclear units. Susceptibility measurements at 10 < T < 275 K allowed the evaluation of an antiferromagnetic intradinuclear exchange coupling J0 = -294 ± 5 cm-1 between CuII ions (Hex = "J0 S1·S2). EPR experiments at 300 K in powder and single-crystals at 9.5 and 34.4 GHz indicated g// = 2.373, g⊥ = 2.073 and zero field splitting parameters D = (-0.334 ± 0.001) cm"1 and E ca. 0. EPR signal intensity measurements at X-band in the range 4 < T < 295 K indicated that J0 = "283 ± 5 cm"1. A higher limit |J´| < 5×10-3 cm-1 for the interdinuclear exchange coupling between neighbor units at ca.14.24 Å was estimated from the angular variation of the single crystal spectra around the magic angles. The results are discussed in terms of the structure of the dinuclear unit and the bridges connecting CuII ions and compared with values reported for similar compounds.
Resumo:
Chemical reactivity, photolability, and computational studies of the ruthenium nitrosyl complex with a substituted cyclam, fac-[Ru(NO)Cl(2)(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl center dot H(2)O ((1-carboxypropyl) cyclam = 3-(1,4,8,11-tetraazacyclotetradecan-1-yl) propionic acid)), (I) are described. Chloride ligands do not undergo aquation reactions (at 25 degrees C, pH 3). The rate of nitric oxide (NO) dissociation (k(obs-NO)) upon reduction of I is 2.8 s(-1) at 25 +/- 1 degrees C (in 0.5 mol L(-1) HCl), which is close to the highest value found for related complexes. The uncoordinated carboxyl of I has a pK(a) of similar to 3.3, which is close to that of the carboxyl of the non coordinated (1-carboxypropyl) cyclam (pK(a) = 3.4). Two additional pK(a) values were found for I at similar to 8.0 and similar to 11.5. Upon electrochemical reduction or under irradiation with light (lambda(irr) = 350 or 520 nm; pH 7.4), I releases NO in aqueous solution. The cyclam ring N bound to the carboxypropyl group is not coordinated, resulting in a fac configuration that affects the properties and chemical reactivities of I, especially as NO donor, compared with analogous trans complexes. Among the computational models tested, the B3LYP/ECP28MDF, cc-pVDZ resulted in smaller errors for the geometry of I. The computational data helped clarify the experimental acid-base equilibria and indicated the most favourable site for the second deprotonation, which follows that of the carboxyl group. Furthermore, it showed that by changing the pH it is possible to modulate the electron density of I with deprotonation. The calculated NO bond length and the Ru/NO charge ratio indicated that the predominant canonical structure is [Ru(III)NO], but the Ru-NO bond angles and bond index (b.i.) values were less clear; the angles suggested that [Ru(II)NO(+)] could contribute to the electronic structure of I and b.i. values indicated a contribution from [Ru(IV)NO(-)]. Considering that some experimental data are consistent with a [Ru(II)NO(+)] description, while others are in agreement with [Ru(III)NO], the best description for I would be a linear combination of the three canonical forms, with a higher weight for [Ru(II)NO(+)] and [Ru(III)NO].
Resumo:
Objectives: To evaluate the effect of laser irradiation (LI) on the glycemic state and the histological and ionic parameters of the parotid and submandibular glands in rats with diabetes. Methods: One hundred twenty female rats were divided into eight groups. Diabetes was induced by administration of streptozotocin and confirmed later according to results of glycemia testing. Twenty-nine days after the induction, the parotid and submandibular glands of the rats were irradiated with 5, 10, and 20 J/cm(2) using a laser diode (660nm/100mW) (without diabetes: C5, C10, and C20; with diabetes: D5, D10, and D20, respectively). On the following day, the rats were euthanized, and blood glucose determined. Histological and ionic analyses were performed. Results: Rats with diabetes without irradiation (D0) showed lipid droples accumulation in the parotid gland, but accumulation decreased after 5, 10, and 20 J/cm(2) of laser irradiation. A decrease in fasting glycemia level from 358.97 +/- 56.70 to 278.33 +/- 87.98mg/dL for D5 and from 409.50 +/- 124.41 to 231.80 +/- 120.18 mg/dL for D20 (p < 0.05) was also observed. Conclusion: LI should be explored as an auxiliary therapy for control of complications of diabetes because it can alter the carbohydrate and lipid metabolism of rats with diabetes.
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The structure of laser glasses in the system (Y(2)O(3))(0.2){(Al(2)O(3))(x))(B(2)O(3))(0.8-x)} (0.15 <= x <= 0.40) has been investigated by means of (11)B, (27)Al, and (89)Y solid state NMR as well as electron spin echo envelope modulation (ESEEM) of Yb-doped samples. The latter technique has been applied for the first time to an aluminoborate glass system. (11)B magic-angle spinning (MAS)-NMR spectra reveal that, while the majority of the boron atoms are three-coordinated over the entire composition region, the fraction of three-coordinated boron atoms increases significantly with increasing x. Charge balance considerations as well as (11)B NMR lineshape analyses suggest that the dominant borate species are predominantly singly charged metaborate (BO(2/2)O(-)), doubly charged pyroborate (BO(1/2)(O(-))(2)), and (at x = 0.40) triply charged orthoborate groups. As x increases along this series, the average anionic charge per trigonal borate group increases from 1.38 to 2.91. (27)Al MAS-NMR spectra show that the alumina species are present in the coordination states four, five and six, and the fraction of four-coordinated Al increases markedly with increasing x. All of the Al coordination states are in intimate contact with both the three-and the four-coordinate boron species and vice versa, as indicated by (11)B/(27)Al rotational echo double resonance (REDOR) data. These results are consistent with the formation of a homogeneous, non-segregated glass structure. (89)Y solid state NMR spectra show a significant chemical shift trend, reflecting that the second coordination sphere becomes increasingly ""aluminate-like'' with increasing x. This conclusion is supported by electron spin echo envelope modulation (ESEEM) data of Yb-doped glasses, which indicate that both borate and aluminate species participate in the medium range structure of the rare-earth ions, consistent with a random spatial distribution of the glass components.
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In this work we present a complete characterization and magnetic study of vanadium oxide/hexadecylamine nanotubes (VO(x)/Hexa NT's) doped with Co(2)+ and Ni(2+) ions. The morphology of the NT's has been characterized by transmission electron microscopy, while the metallic elements have been quantified by the instrumental neutron activation analysis technique. The static and dynamic magnetic properties were studied by collecting data of magnetization as a function of magnetic field and temperature and by electron paramagnetic resonance. At difference of the majority reports in the literature, we do not observe magnetic dimers in vanadium oxide nanotubes. Also, we observed that the incorporation of metallic ions (Co(2+), S = 3/2 and Ni(2+), S = 1) decreases notably the amount of V(4+) ions in the system, from 14-16% (nondoped case) to 2%-4%, with respect to the total vanadium atoms (fact corroborated by XPS experiments) anyway preserving the tubular nanostructure. The method to decrease the amount of V(4+) in the nanotubes improves considerably their potential technological applications as Li-ion batteries cathodes. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3580252]
Resumo:
Oxidation of ethanol on ruthenium-modified Pt(775) and Pt(332) stepped electrodes has been studied using electrochemical and FTIR techniques. It has been found that the oxidation of ethanol on these electrodes takes place preferentially on the step sites yielding CO(2) as the major final product. The cleavage of the C-C bond, which is the required step to yield CO(2), occurs only on this type of site. The presence of low ruthenium coverages on the step sites promotes the complete oxidation of ethanol since it facilitates the oxidation of CO formed on the step from the cleavage of the C-C bond. However, high ruthenium coverages have an important inhibiting effect since the adatoms block the step sites, which are required for the cleavage of the C-C bond. Under these conditions, the oxidation current diminishes and the major product in the oxidation process is acetic acid, which is the product formed preferentially on the (111) terrace sites.