1,559 research outputs found
New long-lived particle searches in heavy-ion collisions at the LHC
We show that heavy-ion collisions at the LHC provide a promising environment to search for signatures with displaced vertices in well-motivated new physics scenarios. Compared to proton collisions, they offer several advantages: (i) the number of parton level interactions per collision is larger, (ii) there is no pileup, (iii) the lower instantaneous luminosity compared to proton collisions allows one to operate the LHC experiments with very loose triggers, and (iv) there are new production mechanisms that are absent in proton collisions We focus on the third point and show that the modification of the triggers alone can increase the number of observable events by orders of magnitude if the long-lived particles are predominantly produced with low transverse momentum. Our results show that collisions of ions lighter than lead are well motivated from the viewpoint of searches for new physics. We illustrate this for the example of heavy neutrinos in the Neutrino Minimal Standard Model
Cytotoxic effect of acetogenins and sesquiterpenes obtained from the Red alga Laurencia majuscula
Purpose: To evaluate the cytotoxicity of n-hexane extract and its metabolites obtained from the red alga, Laurencia majuscula, against three cancer cell lines HCT-116 (colon cancer), PC-3 (prostate cancer) and HepG2 (liver cancer) cells; and to identify the phytochemical compound(s) involved.
Methods: Solvent extraction, thin layer chromatography, aluminum oxide column chromatography, and preparative thin layer chromatography (PTLC) were employed for isolating pure compounds from nhexane extract of Laurencia majuscula. Nuclear magnetic resonance (NMR) and mass spectrometry (MS) measurements were used for structural elucidation of the compounds. The cytotoxicity of the nonpolar extract and isolated compounds were evaluated against HCT, PC-3, and HepG2 cells using MTT assay, relative to the standard cytotoxic drug (cisplatin).
Results: Three sesquiterpenes (1, 2 and 8), and five acetogenins (3-7) were isolated from the n-hexane extract. The n-hexane extract showed higher potent cytotoxic effect than sesquiterpenes and the acetogenins (3-7).
Conclusion: These results indicate that the n-hexane extract of Laurencia majuscula exerts significant cytotoxicity against HCT-116, PC-3 and HepG2 cell lines, thus suggesting that the plant extract may be effective chemotherapeutic agents for the management of colon, postrate and liver cancer.
Keywords: Red Sea alga, Rhodomelaceae, Polyketides, Terpenes, Anticance
Local āBattlegroundsā. Relocating multi-level and multi-actor governance of immigration
The multi-level governance (MLG) approach is widely used to understand the complex processes of immigration policymaking. In this literature review, we consider both (i) the vertical dimension of MLG: the local, regional, national, European, or even global level; and (ii) the horizontal dimension of MLG: the relations between public and non-public actors. While focusing on the local level, this review identifies a trend regarding, on the one hand, local processes of bordering, and local policies of inclusion on the other. Furthermore, the article reviews how civil society has responded to the arrival of refugees. It identifies how this literature pays insufficient attention to dimensions of conflict and, more specifically, to how local borders can be challenged. Moreover, it shows a lack of attention to anti-migrant responses, and to the interaction between migrants and civil society regarding immigration governance. Concluding, the paper argues for the adoption of a ābattlegroundā perspective as a more dynamic basis for the MLG approach.Lāapproche theĢorique de la gouvernance multi-niveaux (GMN) est largement utiliseĢe pour comprendre les processus complexes dāeĢlaboration des politiques migratoires. Dans cet article, nous proposons, sous la forme dāun eĢtat de lāart, une analyse de la dimension verticale (niveau local, reĢgional, national, europeĢen ou mondial) et horizontale (relations entre acteurs publics et non publics) de la GMN. CentreĢ sur le niveau local et sur les questions dāasile, cet article identifie une tendance concernant, dāune part, les processus locaux de deĢfinition des frontieĢres, et dāautre part, les politiques locales dāinclusion. En outre, nous examinons comment la socieĢteĢ civile a reĢagi face aux arriveĢes de reĢfugieĢs. Lāarticle montre que la litteĢrature sur la GMN nāa pas accordeĢ assez dāattention aĢ la question du conflit et aĢ la façon dont celui-ci peut deĢplacer les frontieĢres sociales au niveau local. La litteĢrature a insuffisamment abordeĢ les mobilisations anti-migrants et les interactions entre migrants et socieĢteĢ civile. En conclusion, nous ajoutons que le concept de Ā« champ de bataille Ā» (Battlegrounds) permet une compreĢhension plus dynamique de la GMN.La gobernanza multinivel (MLG por su acroĢnimo ingleĢs) es un enfoque ampliamente utilizado para comprender los complejos procesos de formulacioĢn de poliĢticas puĢblicas en torno al tema de la inmigracioĢn. Esta revisioĢn de la literatura analiza tanto la dimensioĢn vertical de la MLG: el nivel local, regional, nacional, europeo o incluso global; como la dimensioĢn horizontal de la misma: las relaciones entre actores puĢblicos y no puĢblicos. CentraĢndose en el nivel local y particularmente en el tema del asilo, esta revisioĢn bibliograĢfica identifica una tendencia con respecto a los procesos locales de frontera por un lado, y las poliĢticas locales de inclusioĢn por el otro. Las dimensiones del conflicto y el coĢmo se desafiĢan las fronteras locales no se tratan exhaustivamente en este documento. Sin embargo, a este respecto revisamos coĢmo la sociedad civil ha respondido a la llegada de refugiados. Esta literatura no ha otorgado suficiente atencioĢn a las respuestas anti-inmigrantes, y a coĢmo la sociedad civil y los migrantes interactuĢan en relacioĢn a la gobernanza de la inmigracioĢn. Concluimos elaborando sobre la manera en la que un marco conceptual en teĢrminos de Ā«campo de batallaĀ» (Battlegrounds) permite aplicar una perspectiva dinaĢmica al entendimiento de la gobernanza multinivel o MLG
āWhen I look at this van, itās not only a vanā: symbolic objects in the policing of migration
The āGo Home Vanā was the centrepiece of the UK governmentās 2013 immigration enforcement campaign. Vehicles were driven around ethnically diverse London neighbourhoods clad with giant posters offering irregular migrants a choice between āvoluntary departureā and criminal arrest. Abandoned shortly afterwards in response to complaints, the GHV nonetheless had a significant impact on migrants. Through interviews and focus groups, this article investigates what was conveyed by the van, and the means by which it achieved these effects. We find that the GHV communicated meanings about the illegitimacy and criminality of migrants, with its material characteristics (visibility and mobility) as important as the words and pictures on its surface. Migrants sought to resist the van through hiding, while support organisations rejected dominant meanings and crafted alternatives. The article establishes a research agenda around the wider role of symbolic objects, in the context of the global migration crisis
Adequate Levels of Adherence with Controller Medication Is Associated with Increased Use of Rescue Medication in Asthmatic Children
Peer reviewedPublisher PD
Synthesis and characterization of biocompatible methacrylated Kefiran hydrogels: towards tissue engineering applications
Hydrogel application feasibility is still limited mainly due to their low mechanical strength and fragile nature. Therefore, several physical and chemical cross-linking modifications are being used to improve their properties. In this research, methacrylated Kefiran was synthesized by reacting Kefiran with methacrylic anhydride (MA). The developed MA-Kefiran was physicochemically characterized, and its biological properties evaluated by different techniques. Chemical modification of MA-Kefiran was confirmed by 1H-NMR and FTIR and GPC-SEC showed an average Mw of 793 kDa (PDI 1.3). The mechanical data obtained revealed MA-Kefiran to be a pseudoplastic fluid with an extrusion force of 11.21 ± 2.87 N. Moreover, MA-Kefiran 3D cryogels were successfully developed and fully characterized. Through micro-CT and SEM, the scaffolds revealed high porosity (85.53 ± 0.15%) and pore size (33.67 ± 3.13 μm), thick pore walls (11.92 ± 0.44 μm) and a homogeneous structure. Finally, MA-Kefiran revealed to be biocompatible by presenting no hemolytic activity and an improved cellular function of L929 cells observed through the AlamarBlue® assay. By incorporating methacrylate groups in the Kefiran polysaccharide chain, a MA-Kefiran product was developed with remarkable physical, mechanical, and biological properties, resulting in a promising hydrogel to be used in tissue engineering and regenerative medicine applications.H. Radhouani and C. Goncalveswere supported by the Foundation for Science and Technology (FCT) fromPortugal, with references CEECIND/00111/2017 and SFRH/BPD/94277/2013, respectively. S. Correia and this work were funded by the R&D Project KOAT-Kefiran Exopolysaccharide: Promising Biopolymer for Use in Regenerative Medicine and Tissue Engineering, with reference PTDC/BTMMAT/29760/2017 (POCI-01-0145-FEDER-029760), financed by FCT and co-financed by FEDER and POCI. We also thank Duarte N. Carvalho for input on the schematic representation of the process
Impact of kefiran exopolysaccharide extraction on its applicability for tissue engineering and regenerative medicine
Kefiran is an exopolysaccharide produced by the microflora of kefir grains used to produce the fermented milk beverage kefir. The health-promoting and physicochemical properties of kefiran led to its exploration for a range of applications, mainly in the food industry and biomedical fields. Aiming to explore its potential for tissue engineering and regenerative medicine (TERM) applications, the kefiran biopolymer obtained through three different extraction methodologies was fully characterized and compared. High-quality kefiran polysaccharides were recovered with suitable yield through different extraction protocols. The methods consisted of heating the kefir grains prior to recovering kefiran by centrifugation and differed mainly in the precipitation steps included before lyophilization. Then, kefiran scaffolds were successfully produced from each extract by cryogelation and freeze-drying. In all extracts, it was possible to identify the molecular structure of the kefiran polysaccharide throughĆĀ 1H-NMR and FTIR spectra. The kefiran from extraction 1 showed the highest molecular weight (~3000 kDa) and the best rheological properties, showing a pseudoplastic behavior; its scaffold presented the highest value of porosity (93.2% Ʊ 2), and wall thickness (85.8 Ƶm Ʊ 16.3). All extracts showed thermal stability, good injectability and desirable viscoelastic properties; the developed scaffolds demonstrated mechanical stability, elastic behavior, and pore size comprised between 98Ć¢ 94 Ƶm. Additionally, all kefiran products proved to be non-cytotoxic over L929 cells. The interesting structural, physicochemical, and biological properties showed by the kefiran extracts and cryogels revealed their biomedical potential and suitability for TERM applications.H. Radhouani and C. GonƧalves were supported by the Foundation for Science
and Technology (FCT) from Portugal, with references CEECIND/00111/2017 and SFRH/BPD/94277/
2013, respectively. S. Correia and this work were funded by the R&D Project KOATāKefiran
Exopolysaccharide: Promising Biopolymer for Use in Regenerative Medicine and Tissue Engineering,
with reference PTDC/BTMMAT/29760/2017 (POCI-01-0145-FEDER-029760), financed by FCT and
co-financed by FEDER and POCI, and by the Project āHEALTH-UNORTE: Setting-up biobanks and
regenerative medicine strategies to boost research in cardiovascular, musculoskeletal, neurological,
oncological, immunological and infectious diseasesā, ref. NORTE-01-0145-FEDER-000039 funded
under the program NORTE-45-2020-20āSistema de Apoio Ć Investigação CientĆfica e Tecnológicaā
āProjetos Estruturados de I&D&Iā UNorte. We also thank Duarte N. Carvalho for input on the
schematic representation of the process
Algal Remediation of Wastewater Produced from Hydrothermally Treated Septage
Hydrothermal carbonization (HTC) is a promising technology to convert wet wastes like septic tank wastes, or septage, to valuable platform chemical, fuels, and materials. However, the byproduct of HTC, process liquid, often contains large amount of nitrogen species (up to 2 g/L of nitrogen), phosphorus, and a variety of organic carbon containing compounds. Therefore, the HTC process liquid is not often treated at wastewater treatment plant. In this study, HTC process liquid was treated with algae as an alternative to commercial wastewater treatment. The HTC process liquid was first diluted and then used to grow Chlorella sp. over a short period of time (15 days). It was found that the algae biomass concentration increased by 644 mg/L over the course of 10 days, and which subsequently removed a majority of the nutrients in the HTC process liquid. Around 600 mg/L of algal biomass was collected in the process liquid at the end of treatment (day 15). Meanwhile, chemical oxygen demand (COD), total phosphorous, total Kheldjal nitrogen, and ammonia were reduced by 70.0, 77.7, 82.2, and 99.0% by fifteen days compared to the untreated wastewater, respectively. This study demonstrates that HTC process liquid can be treated by growing algae creating a potential replacement for expensive synthetic nutrient feeds for algal production
Effects of a tannin-rich legume (Onobrychis viciifolia) on in vitro ruminal biohydrogenation and fermentation
There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH) of fatty acids (FA) and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia), on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents). Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations) showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (ā17, ā23 and ā11%, respectively). Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies
Social behavioral impairments in SYNGAP1-related intellectual disability
IntroductionDevelopmental synaptopathies are neurodevelopmental disorders caused by genetic mutations disrupting the development and function of neuronal synapses.MethodsWe administered the validated Social Responsiveness Scale, Second Edition (SRS-2) to investigate the phenotypic presentation of social-behavioral impairments for the developmental synaptopathyāSYNGAP1-related Intellectual Disability (SYNGAP1-ID) (nā=ā32) compared with a phenotypically similar disorder Phelan-McDermid syndrome (PMD) (nā=ā27) and healthy controls (nā=ā43). A short form SRS-2 analysis (nā=ā85) was also conducted.ResultsBoth SYNGAP1-ID and PMD had significantly elevated total and subcategory T-scores, with no significant score differences between SYNGAP1-ID and PMD, consistent between the full and short form. Mild to severe deficiencies in reciprocal social behavior were found in 100% of PMD individuals and 87.1% of SYNGAP1-ID individuals. Surprisingly, a positive correlation between age and total score was discovered for SYNGAP1-ID participants and not found in individuals with PMD or healthy controls.DiscussionThe short form demonstrated greater utility for SYNGAP1-ID participants due to lower item-omission rates. In conclusion, significant impairment in reciprocal social behaviors is highly prevalent in SYNGAP1-ID
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