bluuebunny/crossref_metadata_2025 huggingface dataset:
Infezione cronica da HBV: prevalenza e impatto di mutazioni escape sulla risposta alla terapia antivirale.
Authors: Ambra Nicolini Laura , al. et
Published: March 2022

Il virus dell’epatite B (HBV) rappresenta un importante problema sanitario, con 1.5 milioni di nuove infezioni ogni anno. L’infezione da HBV può essere prevenuta dalla vaccinazione con l’antigene HBV ricombinante (HBsAg). mutazioni escape nel “a-determinant” di HBsAg possono causare un cambio conformazionale di HBsAg, che potrebbe evadere la diagnosi di HBV e la seroprotezione indotta dal vaccino.
In questo studio, abbiamo voluto valutare la prevalenza e l’impatto clinico delle mutazioni escape in una coorte retrospettiva di pazienti con infezione cronica da HBV.
Sono stati valutati tutti i pazienti con infezione cronica da HBV, seguiti presso l’Unità di Malattie Infettive del Policlinico San Martino dal 2014 al 2018, con sequenziamento di HBV. Sono state raccolte anche le informazioni sulla coinfezione da HIV e HCV, nonché lo status per HBeAg, il genotipo di HBV e la presenza di mutazioni dei geni S e RT. La risposta virologica era definita da HBV-DNA non rilevabile entro 12 mesi dall’inizio del trattamento, secondo le linee guida EASL.
Complessivamente, sono stati valutati 143 pazienti con HBV, 54 (37.8%) dei quali inclusi nel presente studio. La maggioranza presentava HBV con genotipo D (36/54, 66.6%) e genotipo A (11/54, 20.4%). Nove (16.6%) presentavano almeno una mutazione escape.
Otto pazienti presentavano la mutazione escape prima di iniziare il trattamento per HBV, mentre nell’ultimo il sequenziamento è stato effettuato solo dopo l’inizio del trattamento con entecavir.
Tutti i soggetti con mutazione escape erano negativi per HBeAg prima di iniziare il trattamento per HBV (p=0.04). D’altro canto, le mutazioni escape non erano associate al genotipo D dell’infezione (4/36, 11%, in genotipo D vs. 5/18, 27.7%, p=0.14, in genotipi non-D). La risposta virologica è stata raggiunta in 39 pazienti (72%) e non era associata alle mutazioni escape al basale (p=0.7), alle mutazioni RT (p=0.46) e al genotipo HBV (p=0.33).
Nella nostra coorte, la prevalenza di mutazioni escape era 16-6%. La risposta virologica non era influenzata dalla presenza delle mutazioni.
La reforma del Reglamento Bruselas I bis. Posibilidades y perspectivas
Authors: Hess Burkhard
Published: March 2022

De acuerdo con el artículo 79 del Reglamento (UE) 1215/2012, la Comisión de la UE presentará un informe sobre la aplicación del Reglamento Ibis a más tardar el 11 de enero de 2022. Este documento pretende abrir el debate sobre la situación actual y los ajustes necesarios. del Reglamento. Aunque no es necesario cambiar su estructura básica, debe revisarse la relación del Reglamento Ibis con otros instrumentos de la UE (como el Reglamento general de protección de datos). También es necesario abordar las relaciones con terceros Estados, así como el recurso colectivo transfronterizo. El trabajo aborda además varias inconsistencias dentro del presente Reglamento evidenciadas por la jurisprudencia del TJUE, como el concepto de contrato (artículo 7.1), el lugar del daño (artículo 7.2), la protección de la privacidad y el concepto de consumidor. (artículos 17 a 19). Por último, propone la armonización de algunas normas procesales de ejecución de los Estados miembros de la UE: sobre la evaluación de la propia competencia por los tribunales nacionales, sobre la comunicación judicial y sobre los plazos procesales. En general, la próxima revisión del Reglamento Ibis abre una oportunidad para mejorar aún más un instrumento central y ampliamente aceptado del derecho procesal civil europeo.
La armonización de legislaciones, mercado interior y medio ambiente
Authors: Sadeleer N.  de
Published: March 2022

Este trabajo expone cómo las nuevas propuestas normativas previstas por la Comisión Europea en el marco del Green Deal para alcanzar la neutralidad climática en 2050 se adoptarán sobre la base jurídica medioambiental genuina (artículo 192 del TFUE), o gracias a la base jurídica del mercado interior (artículo 114 del TFUE).
Acerca de los derechos sucesorios del cónyuge viudo
Authors: Vives Velo de Antelo María Patricia
Published: March 2022

Este trabajo pretende realizar un análisis crítico de los derechos sucesorios que el ordenamiento jurídico español concede al cónyuge viudo desde una perspectiva comparada con el Derecho italiano y en el contexto de la realidad social actual. Específicamente se plantea que el deseo de proteger al cónyuge supérstite no debería ir en detrimento de la libertad de testar del causante.
Alegación y prueba del Derecho extranjero: comentario a la sentencia del Tribunal Supremo de 21 de julio de 2021
Authors: Alomar Martín Carmen Dolores
Published: March 2022

La alegación y prueba del Derecho extranjero ha dado lugar a una ingente cantidad de pronunciamientos por parte de nuestros juzgados y tribunales, así como a numerosas aportaciones doctrinales. Si bien, siguen suscitándose los mismos problemas, especialmente los relativos a la carga de la prueba y el papel que deben desempeñar los órganos jurisdiccionales en esta materia. En este trabajo se aborda la sentencia del Tribunal Supremo de 20 de julio de 2021, en la que se mantiene el carácter facultativo de la intervención de los órganos jurisdiccionales en la prueba del Derecho extranjero, al tiempo que nos ofrece unas consideraciones acerca de los medios probatorios, especialmente del informe pericial, que conducen casi inexorablemente a la aplicación de la lex fori.
Restitución de menor a Chile
Authors: Pérez de Colosía y Lázaro Gloria
Published: March 2022

La sustracción o traslado de menores o su retención ilícita por parte de un progenitor o persona que tenga otorgada la guarda por resolución administrativa o judicial, en contra de la voluntad del otro progenitor y en ausencia de una autorización judicial que lo permita constituye un delito castigado por la legislación. Los tiempos de actuación para procurar el inmediato retorno del menor sustraído deben ser muy rápidos y para ello la cooperación internacional, con los instrumentos legales existentes, es indispensable. Crear tratados y convenios internacionales para los Estados que no forman parte de los ya existentes, es imprescindible.
On the applicable law to detrimental acts, third party payments and “assignment” of claims in cross border insolvency proceedings
Authors: Ruiz Martín Anna María
Published: March 2022

In this preliminary ruling (C-73/20), the Court of Justice of the European Union (CJEU) faces again (as did in former case law), the issue of what law is applicable to detrimental acts within the course of a cross border insolvency proceeding. On this occasion, the CJEU analyses how and when, –according to the EU Private International Law (EU PIL) at hand for those proceedings, i.e.: the lex spe-cialis (articles 4 and 13 Insolvency Regulation) and the lex generalis (article 12 para 1 lit a Rome I Re-gulation)–, which one is of application to determine the law applicable to acts which can be considered as “detrimental” to all the creditors. With other words, whether it would be applicable to the detrimental act, the lex concursus which governs the insolvency proceedings as a whole or the lex contractus which governs the law to the contract which led in these detrimental acts. However, the particularity of this case which is highly significant is grounded in the different relationships of the parties as a consequence of an “alleged” assignment between the insolvent company, the original debtor and an outsider creditor to this cross-border insolvency proceeding. Something that the CJEU did not pore it over as expected.
C-581/20, TOTO
Authors: Santaló Goris Carlos
Published: March 2022

In C-581/20, TOTO, the CJEU was asked about two key aspects of the Brussels I bis Regulation jurisdictional regime for interim proceedings. One is whether it is possible to apply for the same provisional measure before the courts of two Member States. The other is whether access to interim measures throughout Article 35 is subject to a European autonomous regime of prerequisites. To the first point, and against the Advocate General Opinion, the CJEU replies that such practice is allowed. Concerning the second point, the CJEU does not even clarify whether there is an autonomous regime of prerequisites exists or not. The CJEU’s answers are less ambitious than the expectations generated by the preliminary reference. This paper offers a comprehensive analysis of the judgment TOTO, evaluating its impact on the interpretation of the Brussels I bis Regulation.
The evolution of the position of Italian Case law concerning public policy in transnational family matters, in view of some recent judgments of the Italian Court of Cassation and Constitutional Court
Authors: Marongiu Buonaiuti Fabrizio
Published: March 2022

The position held by the Italian case law concerning public policy in transnational family law matters has recently experienced some interesting developments, showing an enduring ambiguity between two different notions of public policy for the purposes of private international law, between a “truly international” conception of public policy, whereby it should be considered as purely limited to internationally shared legal principles, concerning especially the protection of fundamental rights, and a more traditional notion. According to the latter notion, public policy for the purposes of private international law shall be considered as embodying mostly national principles, identifying the fundamental attitude of the country at the relevant time, as reflected non only by its constitutional rules, but also by the rules embodied in domestic legislation, insofar as these translate into concrete rules the general principles embodied in the national constitution. Some recent judgments by the Italian Court of Cassation and Constitutional Court concerning topical issues of family law, with particular regard to surrogate motherhood, full adoption by same-sex couples, and repudiation, are particularly telling of this state of affairs. As the author proposes, the dichotomy between the said two notions of public policy for the purposes of private international law is likely to be overcome by suggesting a more flexible reading of the traditional notion, likely to encompass within its scope also those internationally shared legal principles concerning fundamental rights, embodied in the different notion mentioned above, with particular regard to the protection of the best interest of the child, as well as of gender equality.
Recognition of a status acquired abroad in the EU. – A challenge for national laws from evolving traditional methods to new forms of acceptance and bypassing alternatives
Authors: Gössl Susanne , Melcher Martina
Published: March 2022

In view of the ECJ and ECtHR case law on the recognition of names, same-sex marriages and parent-child relationships established abroad, this paper explores how various Member States conform with the resulting obligations. We compared 16 EU jurisdictions and their implementation of the aforementioned case law. Overall, a general tendency in favor of the recognition of a status acquired abroad can be observed; be it by the re-shaping of procedural recognition and private international law rules, or the application of new techniques, or an increasing restraint to reject recognition due to public policy reasons. Irrespective of the technique, however, a methodological struggle to comply with the European obligations is evident. Consequently, the mere registration of a status acquired abroad proves to be of increasing importance in practice.
CESÁREO GUTIÉRREZ ESPADA. De la alargada sombra del ‘ius cogens’
Authors: Calvo Caravaca Alfonso-Luis
Published: March 2022

Este artículo reseña: Cesáreo Gutiérrez Espada. De la alargada sombra del ‘ius cogens’. Granada,Comares, Colección Derecho Transnacional, nº 18, 2021, XIV-198 pp. ISBN: 978-84-1369-220-3
FABRIZIO MARRELLA. Manuale di Diritto del commercio internazionale
Authors: Carrascosa González Javier
Published: March 2022

Este artículo reseña:  Fabrizio Marrella, Manuale di Diritto. Del commercio internazionale. SecondaEdizione, Cedam, Milano, 2020, 936 pp. ISBN 9788813373672
Trastorno de conducta alimentaria durante la pandemia del SARS-CoV-2
Authors: Huete Cordova Maria Antonieta
Published: March 2022

Los pacientes con trastorno de conducta alimentaria (TCA) constituyen una población vulnerable en el contexto de la pandemia por COVID-19. Algunos estudios describen su efecto negativo en los pacientes y sus cuidadores. El presente artículo efectúa una revisión narrativa del impacto de la pandemia en este tipo de pacientes. Se identifican síntomas depresivos, ansiosos, riesgo de autoagresiones y suicidio. La intervención y el manejo tempranos de pacientes con TCA es un gran desafío para la continuidad de tratamiento, detección de comorbilidades y prevención de recaídas.
Prevalencia de los principales trastornos mentales durante la pandemia por COVID-19.
Authors: Mejía-Zambrano Henry , Ramos-Calsín Livia
Published: March 2022

Objetivo: Determinar la prevalencia de los principales trastornos mentales en los trabajadores de la salud y población general, en el contexto de la pandemia por coronavirus 19 (COVID-19). Material y Métodos: El presente artículo sigue las normas de la guía PRISMA para revisiones sistemáticas. Se realizó una búsqueda bibliográfica en PubMed / MEDLINE desde marzo 2020 hasta el 24 de marzo de 2021, con evaluación de las estrategias de búsqueda basada en el programa del Manual Cochrane. Se utilizó asimismo el programa Mendeley para calificar las referencias bibliográficas y eliminar artículos duplicados. Resultados: Se incluyeron22 estudios en el análisis, con un total de 24 593 participantes. En la población general, la ansiedad tuvo una prevalencia de 36,4%; depresión, 26,6%; estrés, 44,2% y trastorno por estrés postraumático (TEPT), 5,9%. Las mujeres presentaron con mayor frecuencia, síntomas de ansiedad y depresión, en tanto que los hombres manifestaron en mayoría, síntomas de estrés. Entre los profesionales de la salud, estrés y alteraciones del sueño fueron los problemas dominantes, ambos con una prevalencia de 43%. Conclusión: La salud mental de los profesionales y trabajadores de salud laborando en primera línea, así como la de la población general se ha visto seriamente comprometida en tiempos de la pandemia COVID-19, con ansiedad, depresión, estrés, insomnio y TEPT como los cuadros más prevalentes.
Ustavnopravna zaštita nacionalnih manjina
Authors: Kuzelj Valentino , Kvartuč Domeniko , Petričušić Antonija
Published: March 2022

Formalni pozitivno-pravni okvir zaštite prava nacionalnih manjina u Republici‎ Hrvatskoj na visokoj je razini uzimajući u obzir odredbe Ustava Republike‎ Hrvatske i Ustavnog zakona o pravima nacionalnih manjina (sa snagom organskog‎ zakona), prihvaćenih i potvrđenih međunarodnih ugovora, te drugih zakona ‎i podzakonskih akata. Dodatno, iz ustavnosudske prakse proizlazi spremnost ‎na zaštitu prava nacionalnih manjina, što je apostrofirano potvrdom‎ st. 2. Izvorišnih osnova, čl. 1. i čl. 3. (iz kojih proizlazi prihvaćanje tzv. političkog‎ ili građanskog koncepta naroda), te čl. 15, st. 4. (individualno pravo pripadnika ‎nacionalnih manjina na služenje svojim jezikom i pismom) dijelom‎ hrvatskog ustavnog identiteta. Stoga je razloge problema u ostvarivanju prava nacionalnih ‎manjina potrebno tražiti u nedostatnom stupnju razvoja društvene i političke kulture.‎
Otvorit ili zatvorit (granice), to je pitanje!
Authors: Popović Nella
Published: March 2022

Rad se bavi pitanjem ulaska radnih migranata u suvremenoj političkoj teoriji ‎i analizira kako tom pitanju pristupaju kozmopolitizam i komunitarizam kao‎ dvije suprotstavljene političko-teorijske struje mišljenja. Cilj rada je pokazati‎ da su ta dva pristupa u nekim točkama pomirljivi unatoč dihotomiji u njihovim ‎temeljnim teorijskim postavkama. U tu svrhu autorica najprije analizira ‎kozmopolitski pristup kroz etiku diskursa i argumente u prilog otvorenijim‎ granicama s pozicije etičkog univerzalizma i jednake moralne vrijednosti svih ‎ljudskih bića. Oni se potom suprotstavljaju komunitarističkim argumentima ‎u prilog ograničavanju prava na useljenje migranata iz perspektive ontoloških,‎ deontoloških, društveno-političkih, pravno-političkih i etičkih argumenata kojima ‎zajednica opravdava svoje pravo na zatvaranje granica. Rad uočava dodirne‎ točke između kozmopolitizma i komunitarizma u načinu određivanja pravila ‎ulaska, te u nužnosti obrazlaganja isključivanja onima kojima je ulazak ograničen ‎ili zabranjen. U zaključnom razmatranju rad promišlja kako uočene teorijske‎ podudarnosti mogu biti važne za položaj radnih migranata na zakonodavnoj ‎i javno-političkoj razini.‎
Study on CerAMfacturing of Novel Alumina Aerospike Nozzles by Lithography-based Ceramic Vat Photopolymerization (CerAM VPP)
Authors: Schwarzer-Fischer Eric , Sieder-Katzmann Jan , Abel Johannes , Propst Martin , Bach Christian , Scheithauer Uwe , Michaelis Alexander
Published: March 2022

Advanced ceramics are recognized as key enabling materials possessing combinations of properties not achievable in other material classes. They are characterized by very high thermal, chemical and mechanical resistance and also usually have a lower density than metals. These properties predestine ceramics for many different applications, especially space applications.In the aerospace sector aerospike nozzles promise performance and application advantages compared to classic bell nozzles but are also inherently more complex to manufacture due to their shape. AM methods drastically simplify or even enable the fabrication of those complex structures while minimising the number of individual parts. The applicability of ceramic AM (“CerAMfacturing”) on rocket engines and especially nozzles is consequently investigated in the frame of the “MACARONIS” project, a cooperation of the Institute of Aerospace Engineering at Technische Universität Dresden and the Fraunhofer Institute for Ceramic Technologies and Systems (IKTS) in Dresden. The goal is to develop novel large size aerospike thrust nozzles including areas of highest resolution and fineness. Finding a suitable AM process that enables the realisation of both aspects is extremely challenging. One possibility could be the hybridization of shaping methods, in that case CerAM VPP (ceramic additive manufacturing via vat photopolymerization) and CerAM FFF (ceramic additive manufacturing via fused filament fabrication) in combination with sinter joining. This contribution focuses on the high resolution CerAM VPP process, in particular the development, characterization and testing of a new photoreactive Al2O3 suspension validated by AM of novel aerospike nozzles.
Galaxies in Timeline Order
Authors: Buglyó Sándor
Published: March 2022

Here, I present an alternate solution for the dark matter problem. I show that the stars of a galaxy’s arm attract each other with a force other than gravity, producing a chain of stars. We already have an abundance of data (ring and multiring galaxies) as proof for the existence of this strong stars’ chain. This attraction force does not end at the galaxy’s boundaries but gets deeper into the cosmos, and it may explain the dark-energy problem. This attraction force affects only stars and seems to have no effect on planets. I also offer a novel timeline order for the well-known galaxies using Hubble classification. I nominate entangled particles for the role that causes this phenomenon.
Impact of COVID-19 on Local Markets: An Application of Garch and Markov-Switching Dynamic Regression
Authors: Abimbola Olawale , Ogbekile Chukwudi , Oseghale Ehizokhale
Published: March 2022

COVID-19, a global health crisis, occurred unexpectedly and has led to global transformation over all countries in the world today. While COVID-19 had claimed lives and led to an economic crisis, the impacts on the financial market cannot be overemphasized. Considering the previous financial crisis, which occurred due to poor regulations and unchecked misconduct by financial market stakeholders, COVID-19 is the first to mention an indirect crisis that almost has no direct relationship to the financial system. Thus, this paper explores the impacts of COVID-19 from a stochastic approach on Local markets by applying the GARCH model to measure the level of volatility of two (2) US stock indexes (NASDAQ and NYSE) and a Europe index (EURONEXT). Our results show that volatility existed before COVID-19, but the volatility rate increased after COVID-19, possibly due to the COVID-19 shock. We also explore the Markov-Switching Dynamic Regression (MSDR) model to corroborate our findings. We validated that there is a very high persistent volatility for all the considered local markets at the early stage COVID-19 period.
Exploring the Association between Misinformation Endorsement, Opinions on the Government Response, Risk Perception, and COVID-19 Vaccine Hesitancy in the US, Canada, and Italy
Authors: Savoia Elena , Harriman Nigel Walsh , Piltch-Loeb Rachael , Bonetti Marco , Toffolutti Veronica , Testa Marcia A.
Published: March 2022

The COVID-19 pandemic has highlighted the adverse consequences created by an infodemic specifically on compliance with public health guidance and vaccine uptake. COVID-19 vaccine hesitancy is a complex construct that is related to health beliefs, misinformation exposure, and perceptions of governmental institutions. This study draws on theoretical models and current data on the COVID-19 infodemic to explore the association between perceived risk of COVID-19, levels of misinformation endorsement, and opinions about the government response on vaccine uptake. We surveyed a sample of 2,697 respondents from the US, Canada, and Italy using a mobile platform between 21-28 May, 2021. Using multivariate regression, we found that country of residence, risk perception of contracting and spreading COVID-19, perception of government response and transparency, and misinformation endorsement was associated with the odds of vaccine hesitancy. Higher perceived risk was associated with lower odds of hesitancy, while lower perceptions of government response, and higher misinformation endorsement were associated with higher hesitancy.
Transição da idade de casos, internações e óbitos em internações por Covid-19 no município do Rio de Janeiro
Authors: Brito dos Santos Cleber Vinicius , Cavalcante João Roberto , Pungartnik Paula Cristina , Guimarães Raphael Mendonça
Published: March 2022

O presente trabalho objetiva analisar a evolução de casos, internações e óbitos por Covid-19 no município do Rio de Janeiro por faixas etárias entre março de 2020 e abril de 2021. Foram calculadas as frequências absolutas e relativas de casos e óbitos por Covid-19 para faixas etárias decenais das semanas epidemiológicas (SE) 13 de 2020 a 21 de 2021 e intervalos de valores esperados por grupo etário e SE. Os resultados mostram que a maior carga de casos correspondeu às faixas etárias de 20 a 29 e 30 a 39 anos. Internações e óbitos se concentraram nos grupos de 60 a 69, 70 a 79 e 80 anos ou mais, com uma marcante tendência de rejuvenescimento da carga de óbitos a partir da SE 10 de 2021. Conclui-se que há uma transição da idade da pandemia no Rio de Janeiro, possivelmente pelo progresso da vacinação, mostrando, portanto, o sucesso desta medida. Reforçamos a necessidade de aceleração do processo de imunização da população para controle e prevenção da Covid-19.
Accuracy of Stereovision-Updated Versus Preoperative CT-Based Image Guidance in Multilevel Lumbar Pedicle Screw Placement
Authors: Fan Xiaoyao , Mirza Sohail K. , Li Chen , Evans Linton T. , Ji Songbai , Paulsen Keith D.
Published: March 2022

Background:

Change in vertebral position between preoperative imaging and the surgical procedure reduces the accuracy of image-guided spinal surgery, requiring repeated imaging and surgical field registration, a process that takes time and exposes patients to additional radiation. We developed a handheld, camera-based, deformable registration system (intraoperative stereovision, iSV) to register the surgical field automatically and compensate for spinal motion during surgery without further radiation exposure.

Methods:

We measured motion-induced errors in image-guided lumbar pedicle screw placement in 6 whole-pig cadavers using state-of-the-art commercial spine navigation (StealthStation; Medtronic) and iSV registration that compensates for intraoperative vertebral motion. We induced spinal motion by using preoperative computed tomography (pCT) of the lumbar spine performed in the supine position with accentuated lordosis and performing surgery with the animal in the prone position. StealthStation registration of pCT occurred using metallic fiducial markers implanted in each vertebra, and iSV data were acquired to perform a deformable registration between pCT and the surgical field. Sixty-eight pedicle screws were placed in 6 whole-pig cadavers using iSV and StealthStation registrations in random order of vertebral level, relying only on image guidance without invoking the surgeon’s judgment. The position of each pedicle screw was assessed with post-procedure CT and confirmed via anatomical dissection. Registration errors were assessed on the basis of implanted fiducials.

Results:

The frequency and severity of pedicle screw perforation were lower for iSV registration compared with StealthStation (97% versus 68% with Grade 0 medial perforation for iSV and StealthStation, respectively). Severe perforation occurred only with StealthStation (18% versus 0% for iSV). The overall time required for iSV registration (computational efficiency) was ∼10 to 15 minutes and was comparable with StealthStation registration (∼10 min). The mean target registration error was smaller for iSV relative to StealthStation (2.81 ± 0.91 versus 8.37 ± 1.76 mm).

Conclusions:

Pedicle screw placement was more accurate with iSV registration compared with state-of-the-art commercial navigation based on preoperative CT when alignment of the spine changed during surgery.

Clinical Relevance:

The iSV system compensated for intervertebral motion, which obviated the need for repeated vertebral registration while providing efficient, accurate, radiation-free navigation during open spinal surgery.
RESPONSE OF THE OLIGO-MIOCENE BIVALVE FAUNA OF THE KUTCH BASIN (WESTERN INDIA) TO REGIONAL TECTONIC EVENTS
Authors: DUTTA SAURAV , CHATTOPADHYAY DEVAPRIYA
Published: March 2022

Tectonic changes have influenced the evolution of the marine community by changing the land and seaway configuration through time. Two such events during the Oligo-Miocene—the closure of the Tethyan seaway due to development of the Gomphotherium Landbridge leading to separation of the Arabian Sea from proto-Mediterranean Sea (∼ 19 Ma) and significant uplift of the Tibetan Plateau marking the initiation of the monsoon (∼ 16 Ma)—represent a classic case of tectonic shift influencing the regional environment of the Indian subcontinent. We investigated the taxonomic and body-size related response of the shallow marine fauna to this regional change using bivalves from 11 time-constrained shellbeds of the Kutch Basin (western India) from three formations—Maniyara Fort (Chattian), Khari Nadi (Aquitanian) and Chhasra (Burdigalian-Langian) representing a time span of ∼ 9 Ma (24.4–15 Ma).

Our collection of over 2000 individuals represents a total of 15 families and 61 morphospecies. The fossils are predominantly calcitic in nature and families of aragonitic composition are often preserved as molds indicating a potential negative effect of diagenesis. The taphonomic nature, however, does not vary substantially across shellbeds and hence, less likely produced a temporal pattern. The five most abundant species, Ostrea latimarginata, Ostrea angulata, Talochlamys articulata, Anomia primaeva, and Placuna lamellata occur in all the formations. The species composition of the Maniyara Fort Formation is substantially different from those of the younger formations, implying the possible effect of biogeographic separation. The absence of proto-Mediterranean taxa in Oligocene shellbeds supports limited faunal exchange between the Mediterranean-Iranian Province (MIP) and the western Indian Province (WIP) as early as ∼ 24.4 Ma (Chattian). Faunal exchange, however, continued between the WIP and the adjacent Eastern African-Arabian Province (EAAP). Formation-specific evenness shows a monotonic decrease from the Maniyara Fort to the Chhasra Formation. However, shellbed-specific analyses of diversity and body size do not show a strong directional trend through time and supports the stasis model. Although it is difficult to rule out the negative influence of taphonomy on the diversity of the studied fauna, the Oligo-Miocene marine bivalve fauna of the Kutch Basin demonstrates little or no influence of the Tethyan closure and Himalayan upliftment on the diversity through time.
An Iranian Worldview: The Strategic Culture of the Islamic Republic
Authors: Parchami Ali
Published: March 2022

Highlighting the nexus between the Islamic Republic’s strategic culture and behavior, this article argues that Iran’s clerical leadership is ideological in its orientation but has always demonstrated tactical nous and pragmatism. Domestically, it pursues Islamification in conformity with Khomeinism. Regionally, it fosters conditions that might force the United States and its European allies out of the Middle East and oblige local governments to seek accommodation. Its network of regional affiliates and proxies are primarily tools of deterrence to safeguard the regime. Nevertheless, Tehran has a penchant for opportunistically promoting regional instability and arming substate actors to ensnare adversaries in protracted conflicts. Its interventionist proclivities are also borne out of domestic exigencies. Paradoxically, the regime compensates for its diminishing legitimacy by becoming even more aggressive at home and adventurous abroad. There are growing signs, however, that the Islamic Republic’s strategic culture may be its undoing.
Lord’s Resistance Army Culture Provides Opening to Prevent Attacks and Advance Humanitarian Efforts
Authors: Matheson Emilee
Published: March 2022

A recent increase in defections from the Lord’s Resistance Army (LRA)—a Central Africa-based religious militia—has resulted in a rise in violent, survival-motivated lootings of local villages and nongovernmental organization (NGO) outposts perpetrated by former LRA members who are deterred from rejoining their home communities by perceived resentment and hostility among local community members. These ongoing hostilities have compounded an existing humanitarian crisis in Central Africa and intensified regional instability. Cultural data show that if NGOs partnered with local leaders, reintegrated LRA defectors, and tailored their reintegration narratives to appeal to LRA cultural biases, they are more likely to preserve NGO resources through a sustainable decrease in attacks and an increase in successful reintegration efforts.
Synthesis and Application of a Low Formation Damage Clay Stabilizer
Authors: Liang Lei , Wang Yanling , Liu Bin , Li Yongfei , Tang Longhao , Bai Baojun , Zhang Ye
Published: March 2022

To develop a low formation damage clay stabilizer, a kind of organic polyether amine clay stabilizer (OPACS) was synthesized. Compared with the commercial clay stabilizers, the application performance of the OPACS was investigated.

OPACS was synthesized with 1, 2-propanediol, 2-(chloromethyl)oxirane and ammonia as main raw materials. The molecular structure of OPACS were characterized by FTIR and NMR, and its anti-swelling performance was tested by centrifugation. Other performance, including its temperature resistance, acid and alkali resistance, elution resistance and etc., were also researched. Different permeability cores were used to test the formation damage of OPACS, and its anti-swelling mechanism was studied by SEM.

The FTIR and NMR spectra showed that the expected product structure was synthesized. When the clay stabilizer was adding with 2.0 wt.%, the anti-swelling rate of OPACS was over 90% which was better than the commercial clay stabilizers (about 80%) we bought. At the temperature range of 20 °C-120 °C and the pH range of 2-12, the anti-swelling rate of OPACS changed less than 2.5%. In the long-term efficacy test, the elution recovery rate of OPACS was higher than 92% within the concentration between 0.5 wt.%-3.0 wt.%. Natural cores with different permeability were selected for core flow experiments. The test results showed that the permeability recovery rate of cores were more than 95% treated with OPACS, which meant the formation damage value was less than 5%. From the SEM of clay treated with different clay stabilizers, we could find out the structure of clay treated with OPACS was more compact than those treated with other stabilizers we bought. These results have shown that OPACS can effectively inhibit the water absorption swelling of clay and recovery formation damage, which are helpful to the EOR and friendly to the environment.
Leveraging 3D High Resolution PSDM Data Volumes for Early Geohazard Detection
Authors: Lagomarsino Daniela , Fornari Matteo , Barbieri Chiara , Ciccarone Tommaso , Lomartire Alessandro , Norelli Emilio , Rosa Dario
Published: March 2022

The exploiting of High Resolution (HR) Pre Stack Depth Migration (PSDM) 3D seismic volumes, normally used for Oil & Gas exploration, has been pushed forward in geomorphological and geohazard risk evaluation. The novel approach proposed here allows to carry out such activities very early in respect of the standard work flow. Early awareness of critical areas turns out to be crucial in fast-tracking projects and allows a design to cost optimization.

The 3D HR PSDM outputs are processed in order to generate a detailed imaging of the shallower portion of the seismic volumes. The volumes are processed at a 2 meters depth interval and converted in time (DTT). Finally, a dedicated post migration time processing sequence, followed by time-to-depth conversion, is applied to generate a Higher Resolution Volume (HRV) in depth domain. The resulting 3D volume is then analyzed to study the seabed and the sub-bottom from a geomorphological standpoint. The analyses focus on the identification and mapping of the distribution of the "areas of instability" eventually classified according to a specific KPI (Safety Factor Index in static conditions), providing a quantitative slope stability assessment of the area.

The new approach has been validated comparing the DTM (Digital Topographic Model) derived from the 3D HR PSDM volume and the available MBES (Multi Beam Echo Sounder) bathymetry.

The proposed approach leads to a dramatic improvement in the detection capability, highlighting the major critical structures such as: canyon flanks, buried slides, creeps and tension cracks on the shelf break, boulders and compacted sediments, sediment banks and sediment waves reshaped by bottom currents, pockmark areas and fluid escapes, turbidity mass movements and furrows due to tectonic activities. The approach matches perfectly the detection capability of a traditional MBES approach.

The described workflow is potentially highly beneficial for early de-risking assets and operations, especially for facilities installation. The proposed innovative approach allows a detailed planning of dedicated data acquisition campaigns, restricted to the most critical areas, with a tangible reduction in the turnaround times and cost savings crucial for project economics.
A Comprehensive Analysis of Water Alternating Gas Recovery Mechanisms in a Giant Middle East Field
Authors: Schreiber Pierre-Edouard , Osorio Ochoa Andrea , Hild Jean-Claude , Prinet Catherine , Bourgeois Marcel , Kumar Amit , Bartolome Pablo
Published: March 2022

This paper is based on a study performed on an offshore Middle East field. The field is a giant complex mostly carbonate oil field, which is characterized by a thin oil column, a low permeability associated with fractures, a large transition zone and a lateral variation in fluid properties. Even after an extensive and efficient water-flood development, there are substantial amounts of oil remaining in the reservoir due to the highly oil-wet nature of the rock. Various Enhanced Oil Recovery (EOR) techniques have been envisaged to enhance oil production. The most mature one is the immiscible hydrocarbon Water Alternating Gas (WAG) injection. This High Pressure (HP)-WAG project started in September 2012 after the encouraging results of the continuous Low Pressure (LP) gas injection trial performed in 2008.

This paper presents the latest analysis of the performances of this HP-WAG project. The HP-WAG project performances is evaluated through (i) the oil gain (versus a water-flood baseline), (ii) the water injectivity evolution over the WAG cycles, (iii) the gas management and (iv) the well and surface integrity. The paper also aims to share the methodology for analyzing the contribution of the main mechanisms occurring over the WAG cycles: the oil-gas interaction mechanisms and the desaturation mechanisms. The oil-gas interactions that occur in immiscible gas injection cases lead to significant long-lasting WAG effects thanks to both the swelling effects that continue even once the oil is saturated and a permanent mobility ratio improvement. The contribution of both macroscopic and microscopic oil desaturation is also described and quantified in this paper.

The work presented in this paper has evidenced the HP-WAG technique benefits and has improved the understanding of the impacts of the main mechanism occurring in the reservoir. This knowledge paved the way towards more extensive WAG deployment on the field. It also emphasized the need of laboratory experiments to calibrate the three-phase models and the absolute need of compositional models to capture the entire WAG benefits even in immiscible gas injection cases.
Recent Advances of Polymer Flooding in China
Authors: Guo Hu , Lyu Xiuqin , Xu Yang , Liu Shaopeng , Zhang Yuxuan , Zhao Fengxiang , Wang Zhengbo , Tang Engao , Yang Zhaopeng , Liu Huifeng , Song Kaoping
Published: March 2022

Polymer flooding is one of the most promising chemical enhanced oil recovery (EOR) techniques which have high incremental oil recovery factor (IORF), low cost and wide reservoir applicability. The first field test of polymer flooding was reported in the United States in 1960s. The first large commercial polymer flooding in China started in Daqing oilfield, which has been remained the largest application in the world. However, encouraged by the conventional field applications and new findings of polymer's viscoelasticity effect on residual oil saturation (ROS) reduction, some high concentration high molecular weight polymer flooding (HCHMW) field tests have been conducted and reported. Although some field tests were well documented, subsequent progress was seldom reported. According to a recent review of latest polymer flooding projects in China, it is found that HCHMW have only very limited application in Daqing. This is not in agreement with the expectations especially that viscoelastivity of synthetic partically hydrolyzed polyacrylamide (HPAM) is drawing much attention recently. This paper explains why HCHMW is not widely used at present. Different opinions on polymer's viscoelasticity effect on ROS reduction are also critically reviewed. Other field progress of salt-tolerance polymer flooding tests and new amphiphilic polymer tests in Daqing were summarized. Associative polymer (APs) commercial application in offshore reservoirs and some new polymers used in China were also involved. Risk of high polymer injection pressure, optimum viscosity ratio, blocking mechanism, and capillary number theory are discussed. Learnings from many polymer flooding field applications has been given. In the end, quaternary recovery practices in post-polymer flooding reservoirs were compared. This paper helps to clarify some misleading ideas in polymer flooding implementations based on theory and practices of polymer flooding in China.
Interpretation of the Alkaline-Surfactant-Polymer Pilot in West Salym Using Tracers
Authors: Karpan Volodimir , de Reus Jasper , van Batenburg Diederik , Mikhaylenko Egor
Published: March 2022

An Alkaline-Surfactant-Polymer (ASP) pilot was executed in the West Salym oil field in the Russian West-Siberian oil province. To successfully interpret the project outcome an extensive surveillance plan was put in place. A tracer program formed an important, stand-alone part of the plan. Tracers injection was designed and executed to evaluate the incremental oil production due to ASP injection by using A) change in volume swept between the pilot wells and B) change in oil saturations due to ASP flooding. This paper focusses on the practical aspects of the tracer program execution and how the tracer program results were used for the interpretation of the pilot.

The West Salym reservoir is a sandstone formation with 83°C temperature, 2 cP crude oil viscosity, permeabilities ranging from 10 to 250 mD and porosity ranging from 18 to 22%. The field is operated as a mature waterflood, with oil production having peaked in 2011. To increase the recovery factor, a tertiary oil recovery technique (ASP) was selected. A confined five spot well pattern was chosen for conducting the ASP field trial. Due to low remaining oil saturation after the waterflood (executed also as a pre-flush for the ASP flood) the production watercut reverse due to the ASP injection changed only from 98% to 88-90%. Hence, it was important to evaluate the efficiency of ASP flooding using several independent approaches. In addition to field injection/production data, analytical and modelling techniques, the tracer data interpretation became a valuable source of information.

Four tracer injection stages were conducted during West Salym ASP pilot. Passive and partitioning tracer injection/production data were analyzed using Shook's analytical method and supported by the reservoir modelling. Analytical analysis of field data was complicated by the production and injection upsets, as well as the changes in injected viscosities. Even though the requirement for steady state conditions were not fully met, the passive tracer recovery data provided an important input to the history matching of pilot dynamic model helping to determine the sweep increase due to injection of viscous chemical solutions. The partitioning tracer recovery data in the water post-flush were used to confirm the low residual oil saturation after ASP flooding.
X-Ray Computed Tomography Assisted Investigation of Flow Behaviour of Miscible CO2 to Enhance Oil Recovery in Layered Sandstone Porous Media
Authors: Al-bayati Duraid , Saeedi Ali , Ktao Ipek , Myers Matthew , White Cameron , Mousavi Ali , Xie Quan , Lagat Christopher
Published: March 2022

Reservoir heterogeneity reflected by permeability variation in the vertical direction is expected to significantly impact on the subsurface multiphase flow behaviour. In this context, we have shown previously that during immiscible flooding the crossflow between low and high permeability zones plays a significant role in determining the reservoir performance in terms of the hydrocarbon yield. In this manuscript, the contribution of crossflow to oil recovery in layered sandstone porous media during miscible CO2 flooding is explored. We conducted core flooding experiments using a core sample constructed by attaching two axially split half sandstone plugs each with a different permeability (0.008 and 0.1 (μm)2). The crossflow between the two layers was controlled by placing either a lint-free tissue paper or an impermeable Teflon sheet to represent a layered heterogeneity with and without communication, respectively. Additionally, to better understand the underpinning mechanisms influencing the flood performance, we imaged the samples during flooding using a high-resolution medical X-Ray computed tomography (XCT) scanner.

Our results show that core-scale heterogeneity would indeed play an important role in determining the spatial distribution of the injected CO2during miscible flooding, consequently the oil recovery factor. For instance, our results confirm that permeability heterogeneity in vertical direction would lead to CO2 establishing a prefrential flow path through the high permeability layer leading to its early breakthrough. The above-mentioned CO2 channeling is clearly evident from the X-ray images captured during flooding. However, a reasonble amount of CO2 would still enter the low permeability layer contributing positively to the ultimate oil recovery factor. In fact, the post-processing of the XCT data confirmed the above to take place when cross-layer communication was allowed. The diversion of CO2 from the high to low permeablity layer is believed to be due to the crossflow phenomenon (induced by the viscous and dispersion forces) resulting in a subtle increase (i.e. 1.7%) in the ultimate oil recovery. In a similar study we have done about immiscible flooding, the contribution of crossflow to the overall recovery was found to be about 5%. The less pronounced effect of crossflow under miscible conditions is believed to be due to the absence of capillarity as a more effective driving force behind crossflow. To the best of our knowledge, our core-flooding results as presented in this manuscript and backed by X-ray CT visualisation, are the first set of their kind. They are insightful and would be of interest to the scientific community in revealing how crossflow may control flow behaviour in heterogeneous sandstone reservoirs, with important implications for numerical modelling of CO2 injection.
Challenges & Mitigations in a Matured Gas Field in the Sultanate of Oman
Authors: Yahyaai Faisal , Lawati Basayir , Abri Sara , Salmi Maryam , Razvi Mohamed , Mahruqi Salha , Winchester Arlene , Maartje Koning
Published: March 2022

The SN-Deep field is located in the central area of the Sultanate of Oman, 20 km west of the Qarn Alam (QA) station and is operated by the Gas Directorate. The field consists of three deep sandstone reservoirs with rich and lean gas fluids. 50% of GIIP has been produced resulting in significant pressure depletion. This paper will:

Illustrate the WRFM approaches used to manage some of the late life of the field challenges such as sand production, water breakthrough, and scale formation, which were not predicted during the fields’ development phase. Enhanced field production recovery through new technologies to unlock additional reserves.

Extensive well, reservoir, and field management (WRFM) interventions have reduced the field's production decline and sustained the production performance through the following:

Water producing wells – analytical techniques are used to predict water production and forecast which wells are expected to reach critical rates. Resources are therefore allocated yearly for wells expected to show significant water production, limiting well down time. In addition, velocity strings with water shut-off are deployed to minimize deferment and cost. During interventions, wells with additional behind casing reserves volumes are also produced. Foam assisted lift (FAL) and permanent installation has been used as secondary means to reduce additional hydrostatic heads for wells with high water production. A trial with FAL on some wells showed sustainable gas rate with high WGR after foam injection. Scaling and salting – to prevent declining production potentials, proactive fresh water bull heading is used to treat symptomatic wells. The technique and the frequent well interventions were able to reduce the deferment and the need for other expensive resources. Solids production – sand production in the field is managed via implementing an integrated sand management strategy that covered all aspects related to required investigation, arresting, and control monitoring.