Design and fabrication of densely integrated silicon quantum dots using a VLSI compatible hydrogen silsesquioxane electron beam lithography process

Hydrogen silsesquioxane (HSQ) is a high resolution negative-tone electron beam resist allowing for direct transfer of nanostructures into silicon-on-insulator. Using this resist for electron beam lithography, we fabricate high density lithographically defined Silicon double quantum dot (QD) transistors. We show that our approach is compatible with very large scale integration, allowing for parallel fabrication of up to 144 scalable devices. HSQ process optimisation allowed for realisation of reproducible QD dimensions of 50 nm and tunnel junction down to 25 nm. We observed that 80% of the fabricated devices had dimensional variations of less than 5 nm. These are the smallest high density double QD transistors achieved to date. Single electron simulations combined with preliminary electrical characterisations justify the reliability of our device and process

Heterologous murine and bovine IVF using bottlenose dolphin (Tursiops truncatus) spermatozoa

Assisted reproductive technologies are of great importance for increasing the genetic diversity in captive animals. The use of bovine or murine oocytes in heterologous IVF provides advantages compared to homologous IVF in nondomestic animals, such as the accessibility to oocytes and the availability of well-developed in vitro maturation systems. The aim of this study was to determine the heterologous IVF parameters using cryopreserved dolphin spermatozoa and zona-intact bovine or murine oocytes and to examine the nuclear chromatin status of the dolphin spermatozoa. All the processes involved in the fertilization including embryo cleavage were observed by confocal microscopy and hybrid embryo formation was confirmed by polymerase chain reaction. Heterologous bovine IVF showed no polyspermy, lower percentages of pronuclear formation, and a lower cleavage rate compared to homologous IVF group (34.8% vs. 89.3%). Heterologous murine IVF showed a lower cleavage rate than homologous IVF (9.6% vs. 77.1%). With respect to dolphin sperm chromatin, it was more stable, i.e. more resistant to EDTA-SDS decondensation than the bovine sperm chromatin. This study revealed the stability of the dolphin sperm chromatin and the ability of the dolphin spermatozoa to penetrate zona-intact bovine and murine oocytes, leading to hybrid embryo formation

Contrasts in chemical composition and oxidative potential in PM10 near flares in oil extraction and refining areas in Ecuador

International audienceFor decades, oil extraction in rural sites in the North Amazon Region (NAR) in Ecuador, have generated mixtures of potentially toxic compounds, such as polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s. The main national refinery and the thermal power plant located in Esmeraldas, on the North Pacific Coast (NPC), are also considered as important sources of air contamination. Particulate matter (PM10) emitted at both sites could induce the formation of reactive oxygen species (ROS) in the lungs upon inhalation and could be associated with respiratory diseases. In this study, PM10 mass composition was monitored over a two-year period in both regions: NAR (close to oil platforms and open flares) and NPC (in a public school close to the refinery). PM10 composition was assessed in terms of metal(loid)s, organic and elementary carbon (OC, EC), monosaccharides (levoglucosan, mannosan, galactosan), glucose, polyols (sorbitol, mannitol, arabitol), water soluble ions and polycyclic aromatic compounds (PAHs, oxy-PAHs and nitro-PAHs). Additionally, three complementary biochemical and acellular tests were performed to evaluate the oxidative potential (OP).Results show that the PM10 mass and elemental concentrations were higher in NPC than in NAR. Barium and Mo concentrations, commonly used in oil operations, were up to 1000-fold higher than values recorded in other regions of Ecuador. OC/EC ratios and polyols concentrations were higher in NAR than in NPC, indicating a larger biogenic contribution to the PM mass in this region. In NAR, the main sources associated with ROS burden were biogenic emissions and oil production, as indicated by positive correlations between OP, sugars, Ba, some PAHs and oxy-PAHs. On the other hand, in NPC, associations between NH4+, Ba, As and Ni imply that oil refining and industrial activities are the main contributors to the OP of PM10

Realization of Al FinFET Single electron turnstile co-integrated with a close proximity electrometer SET

This paper presents a novel fabrication process to realize high density silicon based quantum dot devices with close proximity Al and Si gates on ultrathin silicon-on-insulator for spin qubit applications. Al FinFET gates surrounding a Si nanowire channel can adjust tunnelling barrier height electrically, while Si plunger side gates enable precise control of the quantum dots potential. This device is fabricated using a multi-layer electron beam lithography process that is fully compatible with metal oxide semiconductor technology. Low temperature electrical measurements and coulomb oscillation characteristics have demonstrated the capability of this structure to electrostatically define two coupled single electron transistors, one to be used as a turnstile device and the other as an electrometer

Realization of Al tri-gate single electron turnstile co-integrated with a close proximity electrometer SET

This paper presents a novel fabrication process to realize high density silicon based quantum dot devices with close proximity Al and Si gates on ultrathin silicon-on-insulator for spin qubit applications. Al gates surrounding a Si nanowire channel can adjust tunnelling barrier height electrically, while Si plunger side gates enable precise control of the quantum dots potential. This device is fabricated using a multi-layer electron beam lithography process that is fully compatible with metal oxide semiconductor technology. Low temperature electrical measurements and Coulomb oscillation characteristics have demonstrated the capability of this structure to electrostatically define two coupled single electron transistors, one to be used as a turnstile device and the other as an electrometer

Latiné Futures Convening: Collaborating for a Thriving and Engaged Community

Participants were invited to record a 30-second response to the convening discussion prompts. To gather a representative sample of the community, an invitation list was curated to include student scholars, education practitioners, governmental representatives, nonprofit executives, business owners, and community leaders. The convening was by invitation only. Those unable to attend were encouraged to send a delegate. DISCUSSION PROMPTS AND FRAMING How do you think climate change is most likely to impact the future of our city - and what are the supports/tools communities most need to prepare for it? How do we ensure Latiné student success, educational attainment, and workforce training that adequately prepares our students for a changing workforce? Technology is significantly changing the way we work. What do we need to prepare our communities? What is the role of technology and tech justice in the future of a healthy, positive Portland? What do you feel is necessary to create faith in community institutions (including voting and democracy)? Where do you think community engagement is strongest in Portland? Where is it less strong? Why? What could be most helpful to change that

#4Corners4Health Social Media Cancer Prevention Campaign for Emerging Adults: Protocol for a Randomized Stepped-Wedge Trial

BackgroundMany emerging adults (EAs) are prone to making unhealthy choices, which increase their risk of premature cancer morbidity and mortality. In the era of social media, rigorous research on interventions to promote health behaviors for cancer risk reduction among EAs delivered over social media is limited. Cancer prevention information and recommendations may reach EAs more effectively over social media than in settings such as health care, schools, and workplaces, particularly for EAs residing in rural areas. ObjectiveThis pragmatic randomized trial aims to evaluate a multirisk factor intervention using a social media campaign designed with community advisers aimed at decreasing cancer risk factors among EAs. The trial will target EAs from diverse backgrounds living in rural counties in the Four Corners states of Arizona, Colorado, New Mexico, and Utah. MethodsWe will recruit a sample of EAs (n=1000) aged 18 to 26 years residing in rural counties (Rural-Urban Continuum Codes 4 to 9) in the Four Corners states from the Qualtrics’ research panel and enroll them in a randomized stepped-wedge, quasi-experimental design. The inclusion criteria include English proficiency and regular social media engagement. A social media intervention will promote guideline-related goals for increased physical activity, healthy eating, and human papillomavirus vaccination and reduced nicotine product use, alcohol intake, and solar UV radiation exposure. Campaign posts will cover digital and media literacy skills, responses to misinformation, communication with family and friends, and referral to community resources. The intervention will be delivered over 12 months in Facebook private groups and will be guided by advisory groups of community stakeholders and EAs and focus groups with EAs. The EAs will complete assessments at baseline and at 12, 26, 39, 52, and 104 weeks after randomization. Assessments will measure 6 cancer risk behaviors, theoretical mediators, and participants’ engagement with the social media campaign. ResultsThe trial is in its start-up phase. It is being led by a steering committee. Team members are working in 3 subcommittees to optimize community engagement, the social media intervention, and the measures to be used. The Stakeholder Organization Advisory Board and Emerging Adult Advisory Board were formed and provided initial input on the priority of cancer risk factors to target, social media use by EAs, and community resources available. A framework for the social media campaign with topics, format, and theoretical mediators has been created, along with protocols for campaign management. ConclusionsSocial media can be used as a platform to counter misinformation and improve reliable health information to promote health behaviors that reduce cancer risks among EAs. Because of the popularity of web-based information sources among EAs, an innovative, multirisk factor intervention using a social media campaign has the potential to reduce their cancer risk behaviors. Trial RegistrationClinicalTrials.gov NCT05618158; https://classic.clinicaltrials.gov/ct2/show/NCT05618158 International Registered Report Identifier (IRRID)PRR1-10.2196/5039