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This paper examines the growing adoption of laser communication (lasercom) in space missions and payloads for identifying emerging trends and key technology drivers of future optical communications satellite systems. It also presents a comprehensive overview of commercially available and custom-designed lasercom terminals, outlining their characteristics and specifications to meet the evolving demands of global satellite networks. The analysis explores the technical considerations and challenges associated with integrating lasercom terminals into LEO constellations and the Inter-satellite communications service provision in LEO due to their power, size, and weight constraints. By analyzing advancements in CubeSat lasercom technology designed to cater for the emergence of future mega constellations of interacting small satellites, the paper underscores its promising role in establishing high-performance satellite communication networks for future space exploration and data transmission. In addition, a brief overview of our ALIGN planned mission is provided, which highlights the main key operational features in terms of PAT and link budget analysis. [ABSTRACT FROM AUTHOR]

Precision beam pointing plays a critical role in free-space optical communications terminals in uplink, downlink and inter-satellite link scenarios. Among the various methods of beam steering, the use of fast steering mirrors (FSM) is widely adopted, with many commercial solutions employing diverse technologies, particularly focusing on small, high-bandwidth mirrors. This paper introduces a method using lightweight, commercial off-the-shelf components to construct a custom closed-loop steering mirror platform, suitable for mirror apertures exceeding 100 mm. The approach involves integrating optical encoders into two off-the-shelf open-loop actuators. These encoders read the signal reflected on purposefully diamond-machined knurled screw knobs, providing maximum contrast between light and dark lines. The resulting steering mirror has the potential to complement or replace FSM in applications requiring a larger stroke, at the expense of motion speed. In the presented setup, the mirror tilt resolution achieved based on the encoder closed-loop signal feedback is 45 μ rad, with a mean slew rate of 1.5 mrad/s. Importantly, the steering assembly is self-locking, requiring no power to maintain a steady pointing angle. Using the mirror to actively correct for a constantly moving incoming beam, a 5-fold increase in concentration of the beam spot on the center of the detector was obtained compared to a fixed position mirror, demonstrating the mirrors ability to correct for satellite platform jitter and drift. [ABSTRACT FROM AUTHOR]

Partially automated assessment is implemented via the ‘Printable worksheet’ mode in the Numbas e-assessment system to create a mathematical modelling worksheet which is individualised with random parameters but completed and marked as if it were a non-automated piece of coursework, preserving validity while reducing the risk of academic misconduct via copying and collusion. A simple modelling scenario is used for this demonstration. A cylindrical tank of water is draining through a small hole in its base, with the size of the tank, size of the hole and initial volume of water randomised so that the details are different for each student. Students are guided through deriving a model of the movement of water out of their version of the tank, asked to compute the expected time for it to empty and asked to discuss some aspects of the model and their findings in a discursive narrative report. [ABSTRACT FROM AUTHOR]

As programming has become a common feature of undergraduate mathematics degrees, there has been an increasing focus on how to teach and assess the subject to mathematicians. The potential benefits of e-assessment of basic programming exercises have many parallels with assessment in mathematics where e-assessment tools are widely used: the chance to give instant feedback to students offers an opportunity to allow students to work at their own pace, accommodating the disparate background in programming that often exists in undergraduate mathematics cohorts. And the randomisation of question content not only offers a powerful tool for practice, with students able to repeat similar problems over and over, it also can offer some protection against plagiarism in a subject where, just like a solution to some mathematical problems, student answers to identical problems are likely to be very similar. This paper considers an extension to Numbas to automatically assess programming exercises and the successful implementation of the resource in undergraduate modules using the programming languages R and Python. [ABSTRACT FROM AUTHOR]

Background: The rise of major complex public health problems, such as vaccination hesitancy and access to vaccination, requires innovative, open, and transdisciplinary approaches. Yet, institutional silos and lack of participation on the part of nonacademic citizens in the design of solutions hamper efforts to meet these challenges. Against this background, new solutions have been explored, with participatory research, citizen science, hackathons, and challenge-based approaches being applied in the context of public health. Objective: Our aim was to develop a program for creating citizen science and open innovation projects that address the contemporary challenges of vaccination in France and around the globe. Methods: We designed and implemented Co-Immune, a program created to tackle the question of vaccination hesitancy and access to vaccination through an online and offline challenge-based open innovation approach. The program was run on the open science platform Just One Giant Lab. Results: Over a 6-month period, the Co-Immune program gathered 234 participants of diverse backgrounds and 13 partners from the public and private sectors. The program comprised 10 events to facilitate the creation of 20 new projects, as well as the continuation of two existing projects, to address the issues of vaccination hesitancy and access, ranging from app development and data mining to analysis and game design. In an open framework, the projects made their data, code, and solutions publicly available. Conclusions: Co-Immune highlights how open innovation approaches and online platforms can help to gather and coordinate noninstitutional communities in a rapid, distributed, and global way toward solving public health issues. Such initiatives can lead to the production and transfer of knowledge, creating novel solutions in the public health sector. The example of Co-Immune contributes to paving the way for organizations and individuals to collaboratively tackle future global challenges. [ABSTRACT FROM AUTHOR]

GLO:KPD/11may21:hyp14112-fig-0002.jpg PHOTO (COLOR): 2 The Maimai experimental catchments showing the M8 catchment (in its 4.5 ha, post 1988 configuration) and general location within New Zealand and within the Maimai valley. Keywords: isotope tracing; rainfall-runoff processes; runoff modeling; steep hillslopes; subsurface stormflow EN isotope tracing rainfall-runoff processes runoff modeling steep hillslopes subsurface stormflow 1 8 8 05/29/21 20210511 NES 210511 INTRODUCTION Many of our legacy research and observation catchments were developed during the First International Hydrological Decade (IHD) (1965-1974) - a period of intense catchment gauging/instrumentation and arguably the beginning of serious process hydrology. The work by Kavetski and Fenicia (2011) included M8 in a comparison of suitable model representations for different catchments and showed that hydrograph dynamics of the Maimai catchment were adequately captured by a single reservoir non-linear model, consistent with earlier model descriptions of the site that described the system, as "strikingly simple" (Vaché & McDonnell, 2006). Uchida, McDonnell, and Asano (2005) and Uchida, Tromp-van Meerveld, and McDonnell (2005) performed a functional intercomparison of water sources, flowpaths, and MTT of the Maimai site compared to several Japanese sites; and how lateral pipe flow compared to trenched Japanese hillslopes. [Extracted from the article]

Precise patterning within the three-dimensional context of tissues, organs and embryos implies that cells can sense their relative position. During preimplantation development, outside and inside cells rely on apicobasal polarity and the Hippo pathway to choose their fate. Despite recent findings suggesting that mechanosensing might be central to this process, the relationship between blastomere geometry (i.e. shape and position) and the Hippo pathway effector YAP remains unknown. We used a highly quantitative approach to analyse information on the geometry and YAP localisation of individual blastomeres of mouse and human embryos. We identified the proportion of exposed cell surface area as most closely correlating with the nuclear localisation of YAP. To test this relationship, we developed several hydrogel-based approaches to alter blastomere geometry in cultured embryos. Unbiased clustering analyses of blastomeres from such embryos revealed that this relationship emerged during compaction. Our results therefore pinpoint the time during early embryogenesis when cells acquire the ability to sense changes in geometry and provide a new framework for how cells might integrate signals from different membrane domains to assess their relative position within the embryo. [ABSTRACT FROM AUTHOR]

Today's livestock producers face increasing public scrutiny because animal agriculture is often cited as a major contributor to greenhouse gas (GHG) emissions. However, this negative perception does not take into account the carbon (C) sequestration benefits of grazing livestock nor that grazing lands account for 25% of the global soil sequestration potential of soil C storage. Grazing beef cattle and bison are key to healthy grassland ecosystems and provide the most nutrient dense source of protein available for human consumption. Beef and bison producers who graze their livestock are widely recognized as environmental stewards because they use sustainable grazing practices that maintain grassland health. These practices are considered climate-smart agriculture (CSA) because they promote soil C sequestration and resilience to increased climate variability. Yet, these same producers are generally overlooked in GHG reduction and C sequestration incentives because of a relative lack of cost-effective methods to measure C and GHG sinks and sources. Emerging technologies are beginning to bridge that gap by paving the way to develop, implement, and monitor CSA practices. Furthermore, rangelands in the U.S. dedicated to supporting forage-based livestock production amount to nearly 940 million acres. This is more than double the acres dedicated to row crops and represents enormous potential to contribute to U.S. climate change commitments. Successful implementation and monitoring of CSA land management practices creates potential to develop climate-smart livestock commodities that sustainably provide economic incentives to producers operating resilient livestock grazing systems. Recently, South Dakota State University, along with ten external partners, was awarded a CSA commodity development grant by the USDA and NRCS focused on CSA-raised grazing beef cattle and bison in the Northern Great Plains. Specific objectives include: 1) developing and implementing existing and novel CSA practices alongside custom grazing plans; 2) measuring, monitoring, reporting, and verifying CSA practice impacts on GHG emissions, C sequestration, and ecosystem biodiversity of plants, arthropods, and wildlife; and 3) creating sustainable, value-added market opportunities for producers using CSA practices. To achieve these objectives, the project team is partnering with producers throughout the Northern Great Plains and beyond and will provide incentives for CSA practice implementation. Additionally, emerging and novel technologies will be used to collect large-scale data across producer operations and test sites to determine and refine GHG and C sequestration estimates associated with range beef cattle and bison systems. The long-term goal of this project is to provide CSA beef and bison producers with sustainable, value-added market opportunities that align with consumer preferences and demand. [ABSTRACT FROM AUTHOR]

This case study discusses the use of the Numbas e-assessment system to assess computing skills across several modules in a mathematics undergraduate degree programme. The modules include basic computing, quantitative analysis of data, and numerical methods. Several approaches are discussed which fit with the teaching of SPSS, R and MATLAB, including randomised data files and questions which can replicate, and therefore mark, calculations made with R data frames and numerical algorithms, such as root finding and curve fitting. In each case, Numbas offers the opportunity to automatically mark and offer immediate feedback to the student. The application of questions inside a computing module is discussed, with a positive response from students to both practice material and hybrid tests, which include some automatic marking alongside submission of the students' code for manual review. There is clear rationale for using an e-assessment system which is already familiar to students, with features such as adaptive marking and the scaffolding of questions, however limitations to the use of Numbas for this purpose are also discussed. [ABSTRACT FROM AUTHOR]

This paper describes an optical phase lock loop (OPLL) implemented as an ultraselective optical frequency comb line filter. The OPLL is based on a photonic integrated circuit (PIC) fabricated for the first time through a generic foundry approach. The PIC contains a distributed Bragg reflector (DBR) laser whose frequency and phase are stabilized by reference to an optical frequency comb generator. The OPLL output is a single-mode DBR laser line; other comb lines and noise at the output of the OPLL filter are attenuated by >58 dB below the peak power of the OPLL-filter output line. The OPLL bandwidth is up to 200 MHz, giving a filter quality factor greater than 1,000,000. The DBR laser can be tuned over 1 THz (8 nm), enabling different comb lines to be selected. Locking to a comb line with a frequency offset precisely selectable between 4 and 12 GHz is also possible. The coherence between the DBR laser and the comb lines is demonstrated by measurements of the heterodyne signal residual phase noise level, which is below −100 dBc/Hz at 5 kHz offset from the carrier. The OPLL-filter output can be up to 6 dB higher than the peak power of the comb line to be isolated by the filter. This optical gain is a unique characteristic which can significantly improve the SNR of communication or spectroscopy systems. This OPLL is envisaged to be used for high purity, tuneable microwave, millimetre-wave, and THz generation. [ABSTRACT FROM AUTHOR]