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Solute Trapping of Group III, IV, and V Elements in Silicon by an Aperiodic Stepwise Growth Mechanism
With rapid solidification following pulsed laser melting, we have measured the dependence on
interface orientation of the amount of solute trapping of several group III, IV, and V elements (As,
Ga, Ge, In, Sb, Sn) in Si. The aperiodic stepwise growth model of Goldman and Aziz accurately fits
both the velocity and orientation dependence of solute trapping of all of these solutes except Ge. The
success of the model implies a ledge structure for the crystal/melt interface and a step-flow
mechanism for growth from the melt. In addition, we have observed an empirical inverse correlation
between the two free parameters (-“diffusive speeds”) in this model and the equilibrium solute
partition coefficient of a system. This correlation may be used to estimate values of these free
parameters for other systems in which solute trapping has not or cannot be measured. The possible
microscopic origin of such a correlation is discussed.Engineering and Applied Science
Oral Bacterial Microbiota in Digestive Cancer Patients: A Systematic Review
The relation between the gut microbiota and human health is increasingly recognized.
Recently, some evidence suggested that dysbiosis of the oral microbiota may be involved in the
development of digestive cancers. A systematic review was conducted according to the PRISMA
guidelines to investigate the association between the oral microbiota and digestive cancers. Several
databases including Medline, Scopus, and Embase were searched by three independent reviewers,
without date restriction. Over a total of 1654 records initially identified, 28 studies (2 prospective
cohort studies and 26 case-controls) were selected. They investigated oral microbiota composition
in patients with esophageal squamous cell carcinoma (n = 5), gastric cancer (n = 5), colorectal
cancer (n = 9), liver carcinoma (n = 2), and pancreatic cancer (n = 7). In most of the studies, oral
microbiota composition was found to be different between digestive cancer patients and controls.
Particularly, oral microbiota dysbiosis and specific bacteria, such as Fusobacterium nucleatum and
Porphyromonas gingivalis, appeared to be associated with colorectal cancers. Current evidence suggests
that differences exist in oral microbiota composition between patients with and without digestive
cancers. Further studies are required to investigate and validate oral–gut microbial transmission
patterns and their role in digestive cancer carcinogenesis
What is the best surgical option for the resection of transverse colon cancer?
Transverse colon is an infrequent localization of colon cancer and it is burdened by a poor prognosis. The principle of oncological radicality includes primary tumor resection with adequate lymphadenectomy. To date, there is still no consensus on which type of surgical resection perform in case of transverse colon cancer (TCC). Lymphatic drainage and vascularization of this section of the colon is highly variable presenting with different anatomical variants. Moreover, mobilization of the transverse colon can be particularly challenging in comparison to other colon tracts. Despite a lack of standardized definitions, three main surgical options are proposed: segmental colectomy of the transverse colon [transverse colectomy (TC)], extended right colectomy (ERC) and subtotal colectomy (STC). The aim of the present review is to describe the outcomes, limitations and advantages of TC, ERC, and STC for TCC in order to identify possible trends in the current literature suggesting which is the best treatment option in both elective and emergency settings
Improving natural risk management by means of virtual surveys through hazardous volcanic contexts by using Augmented and Virtual Reality
To ensure an efficient natural risk management, we need an in-depth understanding and assessment of risk as well as the adoption of effective prevention measures. Modern techniques such as Augmented Reality (AR) and Virtual Reality (VR) offer the opportunity to explore our environment for professional as well as educational purposes, conveying useful information not only to scientists, but also to at-risk populations. “Virtual navigation on volcanoes by Augmented Reality and 3D-headset” was a geoevent we organized in the framework of the 6th edition of the Italian “Settimana del Pianeta Terra” (Week of Planet Earth) in October 2018. The geoevent featured AR and Virtual Reality exhibits, highlighting the benefits of these tools in applications for Earth monitoring, also with positive contributions in mitigation actions to reduce the impact of natural hazards. We proposed virtual 3D models of volcanic regions in Iceland and Italy (at Etna volcano), which guided the visitors in a virtual survey through hazardous contexts like landslide prone areas and fault zones. The event was supported as part of the 3DTeLC project funded through the Erasmus+ Key Action 2 Strategic Partnerships for Higher Education scheme (Project Reference: 2017-1-UK01-KA203-036719).3DTeLC project funded through the Erasmus+ Key Action 2 Strategic Partnerships for Higher Education scheme (Project Reference: 2017-1-UK01-KA203-036719)PublishedVienna, Austria1TM. Formazion
Analogue modelling of basin inversion: a review and future perspectives
Basin inversion involves the reversal of subsidence in a basin due to compressional tectonic forces, leading to uplift of the basin's sedimentary infill. Detailed knowledge of basin inversion is of great importance for scientific, societal, and economic reasons, spurring continued research efforts to better understand the processes involved. Analogue tectonic modelling forms a key part of these efforts, and analogue modellers have conducted numerous studies of basin inversion. In this review paper we recap the advances in our knowledge of basin inversion processes acquired through analogue modelling studies, providing an up-to-date summary of the state of analogue modelling of basin inversion. We describe the different definitions of basin inversion that are being applied by researchers, why basin inversion has been historically an important research topic and what the general mechanics involved in basin inversion are. We subsequently treat the wide range of different experimental approaches used for basin inversion modelling, with attention to the various materials, set-ups, and techniques used for model monitoring and analysing the model results. Our new systematic overviews of generalized model results reveal the diversity of these results, which depend greatly on the chosen set-up, model layering and (oblique) kinematics of inversion, and 3D along-strike structural and kinematic variations in the system. We show how analogue modelling results are in good agreement with numerical models, and how these results help researchers to better understand natural examples of basin inversion. In addition to reviewing the past efforts in the field of analogue modelling, we also shed light on future modelling challenges and identify a number of opportunities for follow-up research. These include the testing of force boundary conditions, adding geological processes such as sedimentation, transport, and erosion; applying state-of-the-art modelling and quantification techniques; and establishing best modelling practices. We also suggest expanding the scope of basin inversion modelling beyond the traditional upper crustal "North Sea style " of inversion, which may contribute to the ongoing search for clean energy resources. It follows that basin inversion modelling can bring valuable new insights, providing a great incentive to continue our efforts in this field. We therefore hope that this review paper will form an inspiration for future analogue modelling studies of basin inversion
Colombia: Doctoral Excursion, Earth Sciences Department ETH Zurich, August 21 – September 5, 2018
Field guide of Doctoral Excursion to Colombia, co-organized by Luz M. Mejia, R.Ott, L. Echeverria-Pazos, E. Erlanger.
Chapter 11: Climate Change Effects on Colombian Biodiversity written by Luz M. Mejia and B. Revels
Solute trapping of group III, IV, and V elements in silicon by an aperiodic stepwise growth mechanism
Augmented Reality applications as dissemination tools for the mitigation of non-structural damage from earthquakes
Mt. Etna covers a region prone to earthquakes with low to moderate magnitude in southern Italy. Nevertheless, its seismicity can yield serious non-structural damage due to the superficial seismic foci. For this reason, it is necessary an effective prevention activity of education and preparedness to seismic hazard for the local populations.
One of the fundamental tasks of the European KnowRISK project (Know your city, Reduce seISmic risK through non-structural elements) is the dissemination of information to reduce non-structural damage from earthquakes in three pilot areas (Portugal, Iceland, and Italy). Focusing on tools that can convey such a useful information among laypersons and students, we choose Augmented Reality (AR) for its interactivity, simplicity and efficacy.
AR enhances the user's perception of and interaction with the real world. It has inspired the “Intelligence Amplification” concept (Brooks, 1996) in which computers are tools to make easier human being life. Elements that “increase” reality are visible using a mobile device, such as a smartphone, through a video camera on board on a tablet, or any new wearable devices.
We tested our first AR application during ScienzAperta in May 2016, an open-door event organized at INGV in Catania, and addressed to pupils and students who live in the Etna region. For that application, we referred to Wikitude trade mark framework provided by Wikitude GmbH (www.wikitude.com), under Android OS version 4+. Throughout ScienzAperta, all visitors were astonished by the AR experience, as the majority of them never heard before about AR applications.
What’s happened after the Pokémon Go! revolution? Actually, the worldwide success of the game makes easy to understand the potential impact of AR, which is not only useful for games. This new video game experience represents indeed a milestone for the future of AR:
“the success of AR games such as Pokémon Go!, which was downloaded more than 100 million times in its first month, reportedly earning $10m per day at the height of its popularity, has attracted widespread attention and investment” (The Gardian, 2016).
As mobile devices (like glasses, smartwatches, etc.) will be even wearable in the next future, many important groups among the biggest technology communities are working hard to create some amazing smart devices (Fig. 1). This will increase the great success of AR technology among the “digital native” generation, raising our motivation to use this new way of communication to disseminate a better culture of safety.Co-financed by European Commissions's Humanitarian Aid and Civil Protection, Grant agreement ECHO/SUB/2015/718655/PREV28PublishedCatania, Italy3T. Pericolosità sismica e contributo alla definizione del rischioope
Awareness on Seismic Risk: How can Augmented Reality help?
To communicate the importance of knowing the risk of non-structural damage caused by earthquakes, we developed applications based on Augmented Reality (AR) features. These applications run on mobile devices, such as tablets and smartphones, by using their video camera and other on-board sensors, such as GPS, accelerometer, and gyrocompass, from which AR users do take advantage. Combined with a specifically designed exhibit, our AR applications can contribute to increase the common awareness on seismic risk, providing useful information on how to have safer homes in case of an earthquake. Building codes do not take into account non-structural elements, leaving communities at risk of injuries, blocking escapes and even causing deaths. In this framework, the personal preparedness is of paramount importance. The development of our AR applications is supported by the European project KnowRISK (Know your city, Reduce seISmic risK through non-structural elements).PublishedReykjavik, Iceland2TM. Divulgazione Scientific
Awareness on Seismic Risk: How can Augmented Reality help?
To communicate the importance of knowing the risk of non-structural
damage caused by earthquakes, we developed applications based on Augmented
Reality (AR) features. These applications run on mobile devices, such as tablets and
smartphones, by using their video camera and other on-board sensors, such as GPS,
accelerometer, and gyrocompass, from which AR users do take advantage. Combined
with a specifically designed exhibit, our AR applications can contribute to
increase the common awareness on seismic risk, providing useful information on
how to have safer homes in case of an earthquake. Building codes do not take into
account non-structural elements, leaving communities at risk of injuries, blocking
escapes and even causing deaths. In this framework, the personal preparedness is of
paramount importance. The development of our AR applications is supported by the
European project KnowRISK (Know your city, Reduce seISmic risK through
non-structural elements).Published485-4922TM. Divulgazione Scientific