bluuebunny/crossref_metadata_2025 huggingface dataset:
Efeitos macroeconômicos do e-commerce na América Latina
Authors: Zagari-Forte Francisco , Serrano-Orellana Karen , Tenesaca-Serrano Karla
Published: February 2024

O artigo examina como o e-commerce, impulsionado pela tecnologia e pela globalização, está transformando a economia global. Atuando como um motor de crescimento, expande as redes de comércio e abre novas oportunidades de desenvolvimento, embora também gere mudanças nos mercados de trabalho, exigindo novas habilidades. O crescimento do e-commerce está alinhado com indicadores econômicos-chave como o PIB e o emprego, e está intimamente vinculado ao aumento do número de usuários da Internet e à velocidade da banda larga, o que impulsiona o consumo e as vendas online. Destaca-se a necessidade de investimento estratégico em infraestrutura e modernização tecnológica, em particular na América Latina, para fomentar o desenvolvimento. Além disso, o aumento do comércio eletrônico transfronteiriço está remodelando as estruturas comerciais tradicionais e enfrenta desafios como a incerteza nos tempos de entrega e a confiança do consumidor. O artigo conclui que o e-commerce é uma força transformadora na economia e na sociedade, com um impacto ainda em processo de descoberta. As economias maiores se beneficiam mais desta abertura comercial, enquanto a revolução se reflete na logística e nas cadeias de suprimentos. Ressalta-se a importância da segurança cibernética e da colaboração entre governos e o setor privado para um desenvolvimento econômico equitativo e sustentável.
Palavras-chave:
E-commerce, globalização, desenvolvimento econômico, infraestrutura digital, mercado de trabalho.
 
ABSTRACT
The article examines how e-commerce, driven by technology and globalization, is transforming the global economy. Acting as a growth engine, it expands trade networks and opens up new development opportunities, although it also generates changes in labor markets, requiring new skills. The growth of e-commerce is aligned with key economic indicators such as GDP and employment, and is closely linked to the increase in the number of Internet users and broadband speeds, which drive consumption and online sales. The need for strategic investment in infrastructure and technological modernization stands out, particularly in Latin America, to foster development. Additionally, the rise of cross-border e-commerce is reshaping traditional commercial structures and faces challenges such as uncertainty in delivery times and consumer confidence. The article concludes that e-commerce is a transformative force in the economy and society, with an impact still in the process of being discovered. Larger economies benefit most from this trade opening, while the revolution is reflected in logistics and supply chains. The importance of cybersecurity and collaboration between governments and the private sector for equitable and sustainable economic development is highlighted.
Keywords:
E-commerce, globalization, economic development, digital infrastructure, job market.
Número completo (Enero-abril)
Authors: León-González PhD. Jorge Luis
Published: February 2024

Editorial
PhD. Yanary Emelina Carvallo-Monsalve
 
Leadership in Cuban construction companies
Francisca María Ramírez-Rodríguez, Dayamí Danyelis Gelabert-Veliz, Enaidy Reynosa-Navarro
 
Enfoque de marca a través de la Sociedad de las Singularidades de Reckwitz
Alex Bustos-Romero, María José Pérez-Espinoza, Adriana Plata-García
 
Reimagining entrepreneurship in the digital age
Emanuel Ferreira-Leite, Javier Solano-Solano, Gloria Ramírez-Elías
 
Breve revisión de la literatura del comercio electrónico y sus implicaciones económicas en el Ecuador
Adriana Santamaría-Mendoza, Carolina Uzcátegui-Sánchez, Paola Vélez-Yaguana
 
Mystery Shopping, revelando a magia da Compra Misteriosa
Ioanna Dimitrakaki, Jean Palomeque-Jaramillo, Izabele Sousa-Barros
 
Clima organizacional en empresas: conceptualización y variables para su evaluación.
José Javier Del Toro-Prada, Fernando Teófilo Fernández-Rodríguez, Reol Zayas-Batista
 
Actions to strengthen logistics in Cuban companies
Carlos Verdecia-Barbié, Yamilka Pino-Sera, Ana de Lourdes Torralbas-Blazquez
 
Efeitos macroeconômicos do e-commerce na América Latina
Francisco Zagari-Forte, Karen Serrano-Orellana, Karla Tenesaca-Serrano
Comparison of Clinical and Radiographic Healing of Periapical Lesions Using MTA or Conventional Filling Materials: Randomized Controlled Clinical Trial
Authors: SÜMBÜLLÜ Meltem , DOĞANAY YILDIZ Ezgi , ÜNLÜ Mehmet Ali , ARSLAN Hakan
Published: February 2024

Objectives The aim of this study was to compare the effect of MTA versus conventional filling materials on the healing of teeth with periapical lesions.
Materials and methods Sixty-four teeth with periapical lesions of greater than 5 mm were divided into two groups; G1) MTA (ProRoot MTA; Dentsply Maillefer, Ballaigues, Switzerland) filling, G2) conventional filling materials (n = 32/group). In MTA group, the apical portion of the root canal was filled with ProRoot MTA and the middle and coronal thirds of the root canal were filled with injectable thermoplasticized gutta-percha system. Patients were followed for 15 months. The data were statistically analyzed with Mann-Whitney U and chi-square test (P = 0.05).
Results With a follow-up rate of 89.06% of all patients for 15 months, favorable outcomes were obtained in 100% in ProRoot MTA and 83.3% in conventional technique. (P < 0.05).
Conclusions ProRoot MTA showed better results compared to conventional filling materials in teeth with periapical radiolucency.
The Effects of Home and Over-The-Counter Whitening Agents on Surface Roughness and Microhardness of High Aesthetic Composites
Authors: KILIÇ DÖNMEZ Elif İpek , HUBBEZOĞLU İhsan
Published: February 2024

Objectives: The aim of this in-vitro study is to compare the effect of the newly released peroxide-free over-the-counter whitening products and the home bleaching material containing carbamide peroxide, on high aesthetic composites.
Materials and methods: In our study, 4 different composites were used: supra-nano(Tokuyama Estelite Asteria), submicron hybrid(Brilliant Ever Glow), nanofil(Filtek Universal Restorative) and finally nano-ceramic(Ceram.x SphereTEC one). A total of 200 disc-shaped composite specimens with 2 mm thickness and 8 mm diameter were prepared using metal molds(n=10). One surface of the samples was polished using Sof-Lex™ XT discs. Composite groups were divided into 5 subgroups as 4 experimental and 1 control groups. Four bleaching products, namely Opalascence Home Type, Mr. Blanc, I-White, Cali White, were used in the experimental groups. It was kept in a drying oven at 37°C to imitate the temperature of the mouth on certain days and hours in accordance with the instructions written in the whitening products prospectus. The surface roughness of the samples was measured with a profilometer and the microhardness values were measured with a fully automatic Micro Hardness Tester. The surfaces were examined with a Scanning Electron Microscopy. Data were evaluated with two-way Variance Analysis and Tukey Test as statistical methods.
Results: According to the surface roughness data, Filtek Universal Restorative's I-White subgroup showed the highest average surface roughness value, and Tokuyama Estelite Asteria's I-White subgroup showed the lowest value. There was a meaningful difference between the composite main groups and the experimental subgroups(p<0.05). According to microhardness data, I-White subgroup of Tokuyama Estelite Asteria showed the highest average microhardness value and the lowest value was Brilliant Ever Glow's I-White subgroup. A meaningful difference was observed between the composite main groups and the experimental subgroups(p<0.05). Although OTC bleaching products did not significantly change the surface roughness and microhardness values of composite resins, when SEM analyzes were examined, it was observed that all OTC bleaching products caused more cleft, crack and defect-like changes on the composite surfaces compared to Opalescence home bleaching agent.
Conclusions: It can be stated that Filtek Universal Restorative material is the composite that is most negatively affected by whitening materials, while Tokuyama Estelite Asteria composite is the least affected.
Scripts homosexuels et sport en contexte postcolonial : expériences sportives « au pays » d’hommes gays originaires d’Afrique francophone et demandant l’asile en France
Authors: Bouchet-Mayer Cyriac , Ferez Sylvain
Published: February 2024

À partir d’entretiens sociobiographiques auprès d’hommes demandant l’asile en France au motif de leur orientation sexuelle ou de leur identité de genre, ou des deux à la fois, les auteurs explorent, dans cet article, le rôle pluriel des pratiques ludo-sportives dans les processus de socialisation sexuelle et genrée. Ils donnent à voir la manière dont les expériences sportives sont tantôt le lieu d’imposition d’un script culturel hétérosexiste hérité de la période coloniale et renforcé depuis, tantôt le lieu de construction de scripts interpersonnels et intrapsychiques homosexuels. Ces deux mouvements, a priori contradictoires, peuvent coexister et s’alimenter réciproquement. Ils sont subis ou maîtrisés par les enquêtés en fonction de leurs dispositions individuelles.
La catégorisation homme-femme en athlétisme à l’heure des droits humains des minorités sexuées et genrées1
Authors: Mascarenhas Elena , Moron-Puech Benjamin
Published: February 2024

Au prisme des droits humains européens, les autaires analysent les catégories sportives de « sexe » à travers la règlementation d’athlétisme de World Athletics et de l’affaire Caster Semenya. Les règlements les prévoyant sont-ils discriminatoires (article 14 CEDH)? Conduisent-ils à des actes de torture et à d’autres traitements inhumains et dégradants (article 3)? Violent-ils la vie privée (article 8)? Comment inclure les personnes intersexuées, transgenres, notamment non binaires, dans les compétitions internationales?

Après avoir montré que la bicatégorisation telle qu’elle est imposée par le règlement de World Athletics est contraire aux droits humains, les autaires envisagent des modifications et des alternatives inspirées d’autres espaces sportifs.
La course à pied dans une association de la communauté lesbienne, gaie, bisexuelle et trans* (LGBT) : inclusivité ou homonormativité?1
Authors: Piau Matthieu
Published: February 2024

Le mouvement sportif de la communauté lesbienne, gaie, bisexuelle et trans* (LGBT) français, institutionnalisé et reconnu par diverses organisations politiques, militantes et sportives, fait la promotion d’une inclusion de toutes les personnes dans des espaces sécuritaires (safe). L’étude d’une des associations historiques de ce mouvement permet cependant de constater la reproduction de hiérarchies sociales et l’absence de remise en question des normes et des catégories du champ sportif. La volonté masculine hégémonique d’intégration et d’adaptation aux normes hétérosexistes et l’apolitisme revendiqué par cette association construisent en réalité une absence de politisation de l’« identité LGBT » affichée, de sorte que les espaces sportifs et sociaux de l’association ne sont pas accessibles également à toutes et à tous.
Représentations télévisuelles des basketteuses lors des championnats du monde et des Jeux olympiques : une incarnation de la nation contextuelle et ambivalente
Authors: Lapeyroux Natacha
Published: February 2024

Les médias reproduisent les stéréotypes de genre dans le sport en sous-médiatisant le spectacle sportif des femmes et en discréditant les sportives qui ne sont pas conformes à la norme (Montañola 2011). À rebours de ces constats, les basketteuses participent aux compétitions dans des tenues qui ne laissent pas apparaître les courbes de leur corps (short et tee-shirt large, hormis quelques exceptions) et se mettent en scène dans des situations de rivalité où le contact physique est la norme. Afin d’analyser les représentations des basketteuses de haut niveau en France, l’auteure a effectué une analyse socio-sémiotique à partir d’un corpus de retransmissions de compétitions sportives des championnats du monde et des Jeux olympiques sur une période de dix années, de 2005 à 2015, de manière diachronique pour saisir les moments de ruptures et les discontinuités (Foucault 1969). Elle montrera que, de 2005 à 2008, les basketteuses françaises étaient trivialisées par les commentateurs sportifs. Puis, de 2009 à 2012, en raison de résultats sportifs décrits comme étant historiques lors des retransmissions de compétitions des Jeux olympiques, les performances sportives des basketteuses françaises ont été reconnues, et cette équipe a été présentée comme incarnant la nation. Enfin, entre 2013 et 2015, n’ayant pas accompli d’exploits sportifs exceptionnels, ces athlètes n’étaient plus dépeintes de façon aussi élogieuse.
Les représentations des corps féminins et vieillissants sous le Troisième Reich
Authors: Malenfant Émilie
Published: February 2024

Au sein de la communauté du peuple (Volksgemeinschaft) nazie, chaque corps joue un rôle déterminé par son identité biologique, notamment sexuelle. Par conséquent, l’historiographie s’est beaucoup intéressée aux corps des femmes sous le nazisme et aux politiques ayant cherché à les contrôler. Pourtant, le corps féminin disparaît des études lorsqu’il atteint un âge avancé. Mobilisant des publications sur la ménopause et un corpus de publicités pour des produits anti-âge destinés aux femmes, l’auteure propose d’observer les représentations du corps des femmes vieillissantes sous le régime nazi et démontre que l’image d’une féminité « problématique » se prolonge jusque dans la vieillesse.
Partisans de la laïcité de droite au Japon
Authors: Date Kiyonobu
Published: February 2024

Cet article a pour but de présenter les caractéristiques des partisans de ce que nous appelons la laïcité de droite au Japon, en se focalisant sur les mouvements populaires de droite voire d’extrême droite, dont notamment celui de la Conférence du Japon (Nippon Kaigi). Dans un premier temps, nous allons rappeler le contexte historique et culturel de ce pays où le shintoïsme tend à échapper à l’application stricte de la séparation du religieux et du politique, prônée par les partisans de la laïcité de gauche. Ensuite, nous retracerons l’histoire des mouvements populaires de droite de l’après-guerre, et étudierons les stratégies dont les lobbyistes de droite se servent pour s’imposer dans la société civile et dans le monde politique. Enfin, en analysant leurs idées sur la séparation des Églises et de l’État, mais aussi sur la famille impériale, les droits de l’homme, la révision de la Constitution et la question du genre, nous arguerons que les valeurs qu’ils défendent ont des affinités avec celles du Parti libéral-démocrate.
La laïcité aux urgences : les obligations religieuses dans le quotidien hospitalier
Authors: Lavoie Bertrand
Published: February 2024

L’objectif de cet article est de présenter des réponses concrètes offertes par des soignants aux manifestations d’obligations religieuses exprimées par des patients dans une salle d’urgence. Il y existe ce que l’on peut nommer une « harmonisation pratique » du pluralisme religieux, en ce sens que les soignants semblent prêts à accommoder un nombre important d’obligations religieuses, ayant pour principales limites des contraintes pratiques, telles que les ressources matérielles, temporelles et humaines disponibles. Bien qu’il puisse exister des oppositions de valeurs aux demandes liées aux obligations religieuses, les fins de non-recevoir ne sont pas usuelles. Le présent article repose sur une étude ethnographique de deux années, commencée à l’automne 2018 et terminée à l’automne 2020, réalisée en collaboration avec les équipes soignantes de quatre salles d’urgence à Montréal et en Estrie, et réunissant un total de 50 participants.
Efficiency of labour duties performance by civil servants: world experience and prospects in Ukraine
Authors: Kulish Anatolii , Myrhorod-Karpova Valeriia , Kiselyova Elena , Kysil Liudmila , Isaieva Nataliia
Published: February 2024

The purpose of this study is to examine the operation of the control mechanism that regulates the alignment of expenditure and income among civil servants and evaluate the effectiveness of their responsibilities. The study utilizes a blend of theoretical and empirical approaches. Theoretical methods encompass various approaches such as analysis, synthesis, concretization, generalization, the method of analogy and modelling. Empirical methods encompass the scrutiny of civil service practices in Ukraine and other nations, an assessment of legal and scientific literature pertaining to the topic and the production of scientific research and findings. The study uncovers inherent deficiencies in anti-corruption mechanisms pertaining to the civil service and the execution of civil servants’ responsibilities, both domestically in Ukraine and on a global scale. It focuses on analysing the functioning and efficacy of the National Agency for the Prevention of Corruption and the authorized units tasked with the prevention and detection of corruption. The authors assert that Ukraine needs a streamlined system to electronically declare the direct expenses of civil servants. The importance of these findings lies in their capacity to guide future revisions to Ukraine’s current legislation regulating civil service operations. The study establishes a basis for suggesting modifications that can improve the efficiency and efficacy of civil service in the context of anti-corruption efforts.
A transmission bottleneck for malaria? Quantification of sporozoite expelling by Anopheles mosquitoes infected with laboratory and naturally circulating P. falciparum gametocytes
Authors: Andolina Chiara , Graumans Wouter , Guelbeogo Moussa , Jan van Gemert Geert , Ramjith Jordache , Harouna Soré , Soumanaba Zongo , Stoter Rianne , Vegte-Bolmer Marga , Pangos Martina , Sinnis Photini , Collins Katharine , Staedke Sarah G , Tiono Alfred B , Drakeley Chris , Lanke Kjerstin , Bousema Teun
Published: February 2024

It is currently unknown whether all
Plasmodium falciparum
infected mosquitoes are equally infectious. We assessed sporogonic development using cultured gametocytes in the Netherlands and naturally circulating strains in Burkina Faso. We quantified the number of sporozoites expelled into artificial skin in relation to intact oocysts, ruptured oocysts, and residual salivary gland sporozoites. Sporozoites were quantified by highly sensitive qPCR; intact and ruptured oocysts by fluorescence microscopy following antibody staining of circumsporozoite protein. In laboratory conditions, higher total sporozoite burden in mosquitoes was associated with a shorter duration of sporogony (p<0.001). Overall, 53% (116/216) of
P. falciparum
infected
An. stephensi
mosquitoes expelled sporozoites into artificial skin. The geometric means of expelled and residual salivary gland sporozoites were 116 (interquartile range (IQR: 33-501) and 21,016 (IQR: 9127-78,380), respectively. There was a strong positive correlation between ruptured oocyst number and salivary gland sporozoite load (ρ=0.8; p<0.0001) and a weaker positive correlation between salivary gland sporozoite load and the number of sporozoites expelled (ρ=0.35; p=0.0002). In Burkina Faso,
An. coluzzii
mosquitoes were infected by natural gametocyte carriers. Among mosquitoes that were salivary gland sporozoite positive, 97.2% (36/37) expelled sporozoites with a geometric mean of 420 expelled sporozoites (IQR: 116-2,779) and harbored a geometric mean of 35,149 residual salivary gland sporozoites (IQR: 20,310-164,900). Again, we observed a strong correlation between ruptured oocyst number and salivary gland sporozoite load (ρ=0.9; p<0.0001) and a positive correlation between salivary gland sporozoite load and the number of sporozoites expelled (ρ=0.7; p<0.0001). Mosquito salivary glands in Burkina Faso harbored 1-3 distinct parasite clones; several mosquitoes expelled multiple parasite clones during probing.Whilst sporozoite expelling was regularly observed from mosquitoes with low infection burdens, our findings indicate that mosquito infection burden is associated with the number of expelled sporozoites. Future work is required to determine the direct implications of these findings for transmission potential.
The mTOR pathway genes mTOR, Rheb, Depdc5, Pten, and Tsc1 have convergent and divergent impacts on cortical neuron development and function
Authors: Nguyen Lena H. , Xu Youfen , Nair Maanasi , Bordey Angelique
Published: February 2024

Brain somatic mutations in various components of the mTOR complex 1 (mTORC1) pathway have emerged as major causes of focal malformations of cortical development and intractable epilepsy. While these distinct gene mutations converge on excessive mTORC1 signaling and lead to common clinical manifestations, it remains unclear whether they cause similar cellular and synaptic disruptions underlying cortical network hyperexcitability. Here, we show that
in utero
activation of the mTORC1 activators,
Rheb
or
mTOR
, or biallelic inactivation of the mTORC1 repressors,
Depdc5
,
Tsc1
, or
Pten
in mouse medial prefrontal cortex leads to shared alterations in pyramidal neuron morphology, positioning, and membrane excitability but different changes in excitatory synaptic transmission. Our findings suggest that, despite converging on mTORC1 signaling, mutations in different mTORC1 pathway genes differentially impact cortical excitatory synaptic activity, which may confer gene-specific mechanisms of hyperexcitability and responses to therapeutic intervention.
Structural mechanisms for VMAT2 inhibition by tetrabenazine
Authors: Dalton Michael P. , Cheng Mary Hongying , Bahar Ivet , Coleman Jonathan A.
Published: February 2024

The vesicular monoamine transporter 2 (VMAT2) is a proton-dependent antiporter responsible for loading monoamine neurotransmitters into synaptic vesicles. Dysregulation of VMAT2 can lead to several neuropsychiatric disorders including Parkinson’s disease and schizophrenia. Furthermore, drugs such as amphetamine and MDMA are known to act on VMAT2, exemplifying its role in the mechanisms of actions for drugs of abuse. Despite VMAT2’s importance, there remains a critical lack of mechanistic understanding, largely driven by a lack of structural information. Here we report a 3.1 Å resolution cryo-EM structure of VMAT2 complexed with tetrabenazine (TBZ), a non-competitive inhibitor used in the treatment of Huntington’s chorea. We find TBZ interacts with residues in a central binding site, locking VMAT2 in an occluded conformation and providing a mechanistic basis for non-competitive inhibition. We further identify residues critical for cytosolic and lumenal gating, including a cluster of hydrophobic residues which are involved in a lumenal gating strategy. Our structure also highlights three distinct polar networks that may determine VMAT2 conformational dynamics and play a role in proton transduction. The structure elucidates mechanisms of VMAT2 inhibition and transport, providing insights into VMAT2 architecture, function, and the design of small-molecule therapeutics.
A Myelin Map of Trunk Folds in the Elephant Trigeminal Nucleus
Authors: Reveyaz Noémie , Schneeweiß Undine , Heise Olivia , Gerhardt Ben , Gui Andreea M , Kaufmann Lena V , Alfken Jette , Reichmann Jakob , Salditt Tim , Hildebrandt Thomas , Brecht Michael
Published: February 2024

Elephants have elaborate trunk skills and large, but poorly understood brains. Here we study trunk representations in elephant trigeminal nuclei, which form large protrusions on the ventral brainstem. These ventral brainstem protrusions have previously been referred to as inferior olive, but a delineation of the olivo-cerebellar tract reveals these (trigeminal) nuclei are not connected to the cerebellum via climbing fibers. In contrast, the olivo-cerebellar tract connects to a large dorsolateral nucleus with a serrated cellular architecture, the putative elephant inferior olive. Dense vascularization and intense cytochrome-oxidase reactivity distinguish several elongated trigeminal putative trunk modules, which repeat in the anterior-posterior direction. We focus on the most anterior and largest of these units, the putative nucleus principalis trunk module. Module neuron density is low and non-neural cells outnumber neurons by ∼108:1. Dendritic trees are elongated along the axis of axon bundles (myelin stripes) transversing the trunk module. Synchrotron X-ray-phase-contrast tomography suggests myelin-stripe-axons transverse the trunk module. We show a remarkable correspondence of trunk module myelin stripes and trunk folds. Myelin stripes show little relation to trigeminal neurons and stripe-axons appear to often go nowhere; we suggest that myelin stripes might serve to separate trunk-fold domains rather than to connect neurons. Myelin-stripes-to-folds mapping allowed to determine neural magnification factors, which changed from 1000:1 proximally to 5:1 in the trunk finger. Asian elephants have fewer (∼640,000) trunk-module neurons than Africans (∼740,000) and show enlarged representations of trunk parts involved in object wrapping. The elephant trigeminal trunk module is exquisitely organized into trunk-fold-related units.
مقدمه
Authors: پانیری جولیانا , استیلر ریو متیو , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

این جزوه شامل ۱۶ بزنامه درسی میان رشته ای و ایده است که الهام بخش یادگیری درباره ی اقیانوس و ارتباط با آن از طریق حس ها است. همه طرح های درسی در یک پروژه تحقیقاتی به نام پیشرفت دانش در مورد متان در قطب شمال (پروژه آکما شماره 287869) توسعه داده شده است.
سمفونی تراوش سرد
Authors: لوسلبن لیزا کاترین , کلریچی مونیکا , هولم ویلادز , پانیری جولیانا , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

تمرکز: برای گوش دادن به صداهای اقیانوس منجمد شمالی و یادگیری در مورد تنوع زیستی اقیانوس منجمد شمالی، به ویژه در نزدیکی تراوشات سرد. ما با ایجاد عبارات صوتی جدید با الهام از اقیانوس آزمایش هایی انجام خواهیم داد. برای دانش‌آموزان مبتلا به اختلال شنوایی، دانش آموز‌ها می‌توانند بیانی بدنی از این موضوع ایجاد کنند و یا از وسایلی استفاده کنند که با آن راحت هستند.

 

اهداف آموزشی: با این فعالیت، دانش آموزان شروع به درک موارد زیر خواهند کرد:

- انبوهی از صداهای قابل شنیدن در اقیانوس و نزدیک به تراوش سرد در بستر دریا.

- اینکه اقیانوس ها، از جمله اقیانوس منجمد شمالی، دارای تنوع زیستی زیادی هستند.

- کشتی اقیانوس شناسی چیست و صداهای انسانی مرتبط با آن.

 

کلیدواژه: تحقیق اقیانوس، اکتشاف، رابطه انسانی یا غیر انسانی در اقیانوس، صداها، مکان، سر و صدا.
زیست نگار کف اقیانوس
Authors: ماریچ فیلیپ , پوتو مارگریتا پائولا , زیمرمن هایکه جین , پانیری جولیانا , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

تمرکز

برای تثبیت یادگیری دانش آموزان در مورد کف اقیانوس به روشی خلاقانه و سرگرم کننده. از طریق ایجاد یک زیست نگار، دانش آموزان به این فکر می کنند که کف اقیانوس چگونه به نظر می رسد و چه گونه هایی در آنجا زندگی می کنند.

 

اهداف یادگیری

در این فعالیت، دانش‌آموزان طراحی، طبقه‌بندی و مکانی برای همه عناصر و شخصیت‌هایی که کف اقیانوس و تنوع زیستی را تشکیل می‌دهند پیدا می‌کنند
تأثیر انسان: ردپای اکولوژیکی
Authors: ماریچ فیلیپ , پوتو مارگریتا پائولا , پانیری جولیانا , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

تمرکز

درک معنای ردپای اکولوژیکی انسان. دانش‌آموزان به سؤالاتی فکر می‌کنند مانند اینکه اعمال ما (به عنوان مثال، تحقیق) چگونه بر محیط اطراف ما تأثیر می‌گذارد و برای کاهش تأثیر انسان بر اقیانوس‌ها چه کاری می‌توانیم انجام دهیم؟

 

اهداف آموزشی

در این فعالیت، دانش‌آموزان یاد می‌گیرند که درک درستی از رابطه خود با اقیانوس‌ها و محیط ‌زیست دریایی ایجاد کنند و امیدواریم برای تبدیل دانش خود به عمل الهام بگیرند.

 

کلیدواژه

تأثیر انسانی، رد پا، عمل.
Anatomical Variations of Pancreas Divisum in Magnetic Resonance Cholangiopancreatography: A Cross-sectional Study
Authors: Choudhury Pradipta Ray , Baruah Prabahita , Agarwal Sushant , Pal Sudipto , Biswas Krishna Kanta , Baro Abhamoni , Sandalylya Bikash , Das Gautam Chandra
Published: February 2024

Introduction: Pancreas divisum is the most common congenital anomaly of the pancreas. It occurs due to failure of fusion of the dorsal and ventral pancreatic buds in the 7th week of intrauterine life, and leads to the formation of a large dorsal pancreatic duct and a small ventral pancreatic duct. Different types of pancreas divisum had been reported in the literature due to varying patterns of fusion of the dorsal and ventral pancreatic ducts. Aim: The present study had been performed to find out the anatomical variations of pancreas divisum, pancreatic ducts and associated congenital anomalies. Materials and Methods: The present cross-sectional retrospective study was carried out in the Department of Radiology, Gauhati Medical College and Hospital, Guwahati, Assam from January 2022 to March 2023. The Magnetic Resonance Cholangiopancreatography (MRCP) plates of 159 patients were collected and studied for variations of pancreas divisum, pancreatic ducts and associated congenital anomalies. Results: In the present study, 34 (29.8%) cases had Type-1 (classical), 5 (4.4%) cases had Type-2 and 75 (65.9%) cases had Type-3 pancreas divisum. Also, 105 (66.03%) cases had Type-1 pancreatic duct and 34 (21.4%) cases had Type-4 pancreatic duct. Four (21%) cases had associated Komi Type- 2A, a choledochal cyst. Conclusion: In the present study, Type-3 pancreas divisum was most common. Also, most cases had Type-1 Major Pancreatic Duct (MPD). Choledochal cysts were found to be mostly associated with pancreas divisum.
Onset and Progression of Urogenital Symptoms after Surgical Menopause: A Prospective Cohort Study
Authors: Anjana C , Resmy CR , Ismail Jisha
Published: February 2024

Introduction: Surgical menopause is the cessation of menstruation resulting from the surgical removal of the uterus and bilateral ovaries, which leads to a sudden decrease in oestrogen levels and its subsequent effects. Urogenital symptoms are chronic and progressive, but only a few women seek medical care for these symptoms, which are often overlooked during routine follow-ups. Aim: To investigate the onset and progression of various urogenital symptoms after surgical menopause. Materials and Methods: A prospective cohort study was conducted in the Department of Obstetrics and Gynaecology at Government Medical College, Thrissur, Kerala, India from January 2020 to December 2020. A total of 110 women who underwent Total Abdominal Hysterectomy (TAH) and Bilateral Salpingo-Oophorectomy (BSO) for benign conditions were included in the study. The women were asked about the onset of urogenital symptoms at six weeks and 12 weeks after surgery. They were required to indicate whether they experienced four urogenital symptoms (vaginal dryness, frequent urination, urinary incontinence, and reduced sexual desire) using a menopause rating scale. The severity of symptoms was categorised as none (0), mild (1), moderate (2), severe (3), or very severe (4). The progression of symptom severity from three months to six months of follow-up was analysed using Chi-square tests. Results: Urogenital symptoms that developed after surgery included vaginal dryness, dyspareunia, bladder symptoms, and reduced sexual desire. At least one of these symptoms developed in 95 (86.4%) women by 12 weeks. Vaginal dryness was reported by 40 subjects (36.4%) at six weeks, with 36 (32.7%) reporting mild symptoms, 4 (3.6%) reporting moderate symptoms, and none reporting severe or very severe symptoms. At 12 weeks, vaginal dryness was reported by 61 subjects (55.5%), with 21 (19.1%) reporting mild symptoms, 18 (16.4%) reporting moderate symptoms, 20 (18.2%) reporting severe symptoms, and 2 (1.8%) reporting very severe symptoms (p-value<0.05). Other symptoms showed a similar pattern of progression. Conclusion: Urogenital symptoms can start as early as six week
Flux tubes, surface magnetism, and the solar dynamo: constraints and open problems
Authors: Schüssler M.
Published: March 2005

The flux‐tube paradigm has proven to be a remarkably useful tool to understand the connection between the dynamo process in the solar interior and its observable manifestations at the surface. After a brief review of the justification of this approach and of its successes, we discuss in some detail its loose ends and the remaining open questions – and attempt to provide some tentative answers. This includes the origin of fields much stronger than the dynamical equipartition value, the structure of the stored magnetic flux (flux tubes versus a magnetic layer) and the importance of convective pumping, as well as processes connected with flux emergence and the subsequent development of the magnetic flux. It is argued that the observations of the surface field indicate a dynamical disconnection of the emerged flux from its roots in the deep convection zone. Based on the ‘explosion’ of magnetic flux tubes, a scenario and an illustrative model for the disconnection process are suggested. In the last part of the paper, the significance of observed properties of the surface magnetism for constraining solar dynamo models a critically discussed. It is shown that some properties of the butterfly diagram do neither confirm nor refute specific dynamo models. Furthermore, the observed phase relationship between the average toroidal and poloidal magnetic field components is shown to result from the tilt angle of bipolar magnetic regions, so that it imposes no constraint for models of the deep‐seated solar dynamo. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quiet sun magnetic fields vs. polar faculae – local vs. global dynamo?
Authors: Okunev O. V. , Domínguez Cerdeña I. , Puschmann K. G. , Kneer F. , Sánchez Almeida J.
Published: March 2005

Quiet Sun magnetic fields in the internetwork are almost ubiquitous. Simultaneous observations in infra‐red and visible lines and high spatial resolution (<0.5″) data in visible lines show that their field strengths range from below few hundred Gauss to kilo‐Gauss. Most of the flux is contained in small‐scale, strong‐field features located mainly in intergranular lanes. The average unsigned flux density exceeds 20 Gauss. The new detections are confirmed by recent quiet Sun observations in the G band. The generation of the strong fields in the internetwork, which may be due to a local dynamo, poses a challenging problem. – Polar faculae (PFe) are small‐scale magnetic features at the polar caps of the Sun. They take part in the solar cycle and are thus likely to be rooted deeply in the solar interior. They are the result of the global dynamo at the solar poles. PFe also possess kilo‐Gauss magnetic fields which have the same polarity as the global magnetic field. The rôle of quiet Sun magnetic field structures and of PFe for the dynamics of the corona and for the solar wind are addressed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cellular dynamo in a rotating spherical shell
Authors: Getling A. V. , Simitev R. D. , Busse F. H.
Published: March 2005

Magnetoconvection in a rotating spherical shell is simulated numerically using a code developed by Tilgner and Busse. The thermal stratification is convectively unstable in the outer part and stable in the inner part of the shell. Regimes are found in which the convective flow is weakly affected by rotation and preserves its cellular structure. The dipolar component of the large‐scale magnetic field exhibits undamped oscillations. It appears that convection cells slightly modified by rotation can be building blocks of the global dynamo. The generation of the magnetic field is thus due to regular “macroscopic” flows, and their structure itself may ensure the presence of the α effect responsible for the action of the dynamo. Such dynamos can be called deterministic, in contrast to those in which the maintenance of the magnetic field is related to the statistical predominance of a certain sign of helicity in the turbulent velocity field. Investigation of conditions under which dynamos of this sort can operate could suggest a more definite answer to the question of the origin of solar and stellar magnetic fields. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stellar activity cycles: observing the dynamo?
Authors: Strassmeier K. G.
Published: March 2005

The enormous complexity of the atmospheric structure observed on the Sun makes it very difficult to compare the Sun with “solar‐type stars”. Clearly, we need to identify parameters that can be observed on the Sun as well as on other stars which can be interpreted unambiguously. The most widely accepted dynamo signature is the presence of an activity cycle, well documented for the Sun and for main‐sequence stars due to the Mount Wilson Ca II H&K project. Only recently have we detected spatial information, differential rotation and possibly meridional flows on other stars and thereby adding another constraint for its interpretation within a dynamo theory. Again, the picture is not complete yet, despite that there is just a single main ingredient that acts as the driving mechanism for activity in all atmospheric layers and the convective envelope of a solar‐type star: the dynamo‐related magnetic field. I stress the importance of mapping stellar surfaces as fingerprints of the underlying dynamo action over long periods of time. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Line formation in turbulent magnetic atmospheres
Authors: Carroll T. A. , Staude J.
Published: March 2005

We present a stochastic formulation of the polarized radiative transfer in an atmosphere permeated by a random magnetic field. On the basis of a Markov process we describe the line formation as a stochastic process which allows us to account for a finite correlation length of the fluctuating structures. The resulting stochastic master equation describes the evolution of the expectation value of the Stokes vector (the macroscopic observable) through the atmosphere. As the correlation length (mean structural length scale of the fluctuating or turbulent elements) appears explicitly in the stochastic transport equation it can be used as a diagnostic parameter from which an estimation of the underlying structural length scale is possible. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
What did William Hunter know about bone?
Authors: McDonald Stuart W. , Russell David
Published: March 2005

This article examines William Hunter's specimens on bone in the Anatomy Museum at the University of Glasgow. By referring to students' notes taken at Hunter's lectures and to the Manuscript Catalogue of his anatomical specimens, we attempt to answer the question, “What did William Hunter know about bone?” Hunter seems to have been particularly interested in the relationship between vascularisation and ossification and many of the specimens illustrate this. He provided his students with reasoned arguments on a number of issues: that the marrow serves as a fat store and not to produce synovial fluid or to keep bones supple; the periosteum serves as an attachment for tendons and ligaments; the rationale for the presence of epiphyses is not readily defined; that bones form by intramembranous and endochondral ossification and that, in the latter, cartilage is replaced by bone. William Hunter narrowly failed to realise that in long bones new bone is laid down by the periosteum and at the epiphysial plates, and is remodeled. These discoveries were to be made by his brother, John. Clin. Anat. 18:155–163, 2005. © 2005 Wiley‐Liss, Inc.
Homochiral Oligopeptides Generated by Induced “Mirror Symmetry Breaking” Lattice‐Controlled Polymerizations in Racemic Crystals of Phenylalanine N‐Carboxyanhydride
Authors: Nery Jose Geraldo , Bolbach Gerard , Weissbuch Isabelle , Lahav Meir
Published: March 2005

The formation of diastereoisomeric libraries of oligopeptides through the heterogeneous polymerization of racemic crystals of phenylalanine N‐carboxyanhydride (PheNCA) is reported. The diastereoisomeric compositions of the oligopeptides formed on polymerization of (R,S) crystals incorporating the deuterium‐tagged S enantiomer were determined by MALDI‐TOF mass spectrometry. The racemic mixtures of the oligopeptides longer than pentamers are represented primarily by diastereoisomers of homochiral sequence and with peptides containing only one heterochiral repeating unit. A mechanism comprising the following three sequential steps to account for this unusual observation is proposed: 1) formation of dimers and trimers at a partially damaged liquid/solid interface, 2) chain propagation that takes place within the bulk of the crystal through a lattice‐controlled “zipper‐like” mechanism between homochiral molecules arranged in a head‐to‐tail motif to yield crystalline antiparallel β‐sheets of alternating oligopeptide chains of homochiral sequence of opposite handedness, and 3) enantiomeric cross‐inhibition that results in chain termination. Induced desymmetrization of the racemic mixtures of the formed peptides was achieved by the polymerization of the mixed quasi‐racemic crystals of (R)‐PheNCA, ((S)‐PheNCA), and (S)‐ThieNCA (3‐(2‐thienyl)‐alanine N‐carboxyanhydride) of various compositions. These experiments resulted in the formation of nonracemic libraries of oligopeptides composed of homochiral chains of (R)‐Phe and copolymers of randomly distributed (S)‐Phe and (S)‐Thie sequences. From these findings, we propose a stochastic model for the generation of libraries of nonracemic mixtures of oligopeptides from the polymerization of host (R,S)‐PheNCA with racemic mixtures of other guest NCA amino acids dissolved in limited quantities in the crystal.
Three‐Dimensional Organization of Helices: Design Principles for Nucleobase‐Functionalized β‐Peptides
Authors: Chakraborty Pradip , Diederichsen Ulf
Published: March 2005

The construction and molecular recognition of various three‐dimensional biomimetic structures is based on the predictable de novo design of artificial molecules. In this regard β‐peptides are especially interesting, since stable secondary structures are obtained already with short sequences; one of them is the 14‐helix in which every third residue has the same orientation. The covalent functionalization of every third 14‐helix side chain with nucleobases was used for a reversible organization of two helices based on nucleobase pairing. A series of β‐peptides with various nucleobase sequences was synthesized and the stability of double strand formation was investigated. As few as four nucleobases are sufficient for considerable duplex stability. The stability of base pairing was examined by temperature‐dependent UV spectroscopy and the formation of the 14‐helix was confirmed by circular dichroism (CD) spectroscopy. The preferred strand orientation of complementary‐nucleobase‐modified β‐peptide helices was investigated as well as the influence of helix content on the duplex stability. The preorganization of a 14‐helix in regard to double‐strand recognition was tuned by the sequential order of polar β‐amino acids or by the amount of 2‐aminocyclohexanecarboxylic acid units incorporated, which are known to facilitate 14‐helix formation, respectively.
Low Temperature Neutron Diffraction Data for CeCo0.86Ge2.
Authors: Gil A. , Penc B. , Hernandez‐Velasco J. , Wawrzynska E. , Szytula A.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Crystal Structures of the Compounds Ln3CuSe6 (Ln: Gd, Tb and Dy) and TbCu0.34Te2.
Authors: Gulay L. D. , Olekseyuk I. D.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Hydrogen Desorption Exceeding Ten Weight Percent from the New Quaternary Hydride Li3BN2H8.
Authors: Pinkerton Frederick E. , Meisner Gregory P. , Meyer Martin S. , Balogh Michael P. , Kundrat Matthew D.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Fluorodihydroxysulfonium Hexafluoroantimonate [FS(OH)2]+[SbF6]‐.
Authors: Kornath Andreas , Seelbinder Raphael , Minkwitz Rolf
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Structural Diversity of Low‐Dimensional Compounds in [M(en)2]2+/ [Re6Q8(CN)6]4‐ Systems (M: Mn, Ni, Cu).
Authors: Brylev Konstantin A. , Pilet Guillaume , Naumov Nikolai G. , Perrin Andre , Fedorov Vladimir E.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Ruthenium‐Catalyzed Enyne Cycloisomerizations. Effect of Allylic Silyl Ether on Regioselectivity.
Authors: Trost Barry M. , Surivet Jean‐Philippe , Toste F. Dean
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Fused Polycycles by 1,4‐Palladium Migration Chemistry.
Authors: Huang Qinhua , Campo Marino A. , Yao Tuanli , Tian Qingping , Larock Richard C.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Selective and Effective Fluorination of Organic Compounds in Water Using Selectfluor F‐TEDA‐BF4.
Authors: Stavber Gaj , Zupan Marko , Jereb Marjan , Stavber Stojan
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Molecular Complex 3‐Methyl‐2,4‐dinitrothiophene 1,1‐Dioxide—Pyridine in Reactions with Amines.
Authors: Efremova I. E. , Lapshina L. V. , Berkova G. A. , Berestovitskaya V. M.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of α‐Hydrazino Ketones via Regio‐ and Stereoselective Electrophilic Amination of Manganese Enolates and Enamines.
Authors: Dessole Gabriella , Bernardi Luca , Bonini Bianca F. , Capito Elena , Fochi Mariafrancesca , Herrera Raquel P. , Ricci Alfredo , Cahiez Gerard
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
A Highly Efficient and Recyclable Silica‐Based Scandium(III) Interphase Catalyst for Cyanosilylation of Carbonyl Compounds.
Authors: Karimi Babak , Ma'Mani Leila
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Reactions of Primary Amines with Tetracyanoethylene.
Authors: Ladilina E. Yu. , Semenov V. V. , Kurskii Yu. A. , Khorshev S. Ya. , Domrachev G. A.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Skeletal Reorganization of Enynes into 1‐Vinylcycloalkenes in Ionic Liquids.
Authors: Miyanohana Yuhei , Inoue Hiroki , Chatani Naoto
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
A New Route for the Convenient Synthesis of 3‐Aminomethyl‐3,5,5‐trimethyl‐cyclohexanol.
Authors: Pandey Satish C. , Singh Sudhir S. , Patro Balaram , Ghosh Anil C.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of New Liquid Crystalline Compounds Containing a β‐Hydroxyketone Fragment in the Side Chain.
Authors: Bezborodov V. S. , Kovganko V. N.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of β‐Monosubstituted α,β‐Unsaturated Amides with Z‐Selectivity Using Diphenylphosphonoacetamides.
Authors: Kojima Satoshi , Hidaka Tsugihiko , Ohba Yuko
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Pharmacological Evaluation of Some DL‐Dichlorophenyl Alcohol Amides Anticonvulsants.
Authors: Meza‐Toledo Sergio E. , Olea‐Gomez Arturo , Mora‐Ramirez Erika Y. , Peralta‐Cruz Javier , Nogueron‐Chirinos Jaisel B.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
An Efficient Synthesis of Biaryls via Noncatalyzed Anionic Coupling of an Arylsodium with Haloarenes.
Authors: Becht Jean‐Michel , Gissot Arnaud , Wagner Alain , Mioskowski Charles
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Stereoconservative Negishi Arylation and Alkynylation as an Efficient Approach to Enantiopure 2,2′‐Diarylated 1,1′‐Binaphthyls.
Authors: Krascsenicsova Katarina , Walla Peter , Kasak Peter , Uray Georg , Kappe C. Oliver , Putala Martin
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis of the Naphthalene‐Derived Inhibitors Against Cdc25A Dual‐Specificity Protein Phosphatase and Their Biological Activity.
Authors: Shimbashi Akiko , Tsuchiya Ayako , Imoto Masaya , Nishiyama Shigeru
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Catalytic Cyclization of o‐Alkynylbenzaldehyde Acetals and Thioacetals. Unprecedented Activation of the Platinum Catalyst of Olefins. Scope and Mechanism of the Reaction.
Authors: Nakamura Itaru , Bajracharya Gan B. , Wu Huanyou , Oishi Kengo , Mizushima Yuya , Gridnev Ilya D. , Yamamoto Yoshinori
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Specific Features of Mesomorphic Behavior of New Polysubstituted Triphenylenes.
Authors: Zemtsova O. V. , Zheleznov K. N.
Published: March 2005

For Abstract see ChemInform Abstract in Full Text.