Phoenix: A CubeSat Mission to Study the Impact of Urban Heat Islands Within the U.S.

Phoenix is a student-led CubeSat mission, developed at Arizona State University (ASU), to study the effects of Urban Heat Islands in several U.S. cities through infrared remote sensing and educate students on space mission design. The spacecraft is designed using commercial off-the-shelf components (COTS) and several custom support boards developed by the student team. As such, the student team was responsible for the design, test, and validation of the spacecraft to demonstrate the capability of using COTS hardware to conduct high-fidelity science. This paper details the mission’s concept of operations, as well as the spacecraft and ground system design that was developed to complete the mission objective. In addition, it details the mission’s current status now that Phoenix has entered the operations phase, along with resources which have proved beneficial to the team while working with the spacecraft in orbit

Distinct cardiovascular phenotypes are associated with prognosis in systemic sclerosis: a cardiovascular magnetic resonance study

AIMS: Cardiovascular involvement in systemic sclerosis (SSc) is heterogeneous and ill-defined. This study aimed to: (i) discover cardiac phenotypes in SSc by cardiovascular magnetic resonance (CMR); (ii) provide a CMR-based algorithm for phenotypic classification; and (iii) examine for associations between phenotypes and mortality. METHODS AND RESULTS: A retrospective, single-centre, observational study of 260 SSc patients who underwent clinically indicated CMR including native myocardial T1 and T2 mapping from 2016 to 2019 was performed. Agglomerative hierarchical clustering using only CMR variables revealed five clusters of SSc patients with shared CMR characteristics: dilated right hearts with right ventricular failure (RVF); biventricular failure dilatation and dysfunction (BVF); and normal function with average cavity (NF-AC), normal function with small cavity (NF-SC), and normal function with large cavity (NF-LC) sizes. Phenotypes did not co-segregate with clinical or antibody classifications. A CMR-based decision tree for phenotype classification was created. Sixty-three (24%) patients died during a median follow-up period of 3.4 years. After adjustment for age and presence of pulmonary hypertension (PH), independent CMR predictors of all-cause mortality were native T1 (P  0.14). Hazard ratios (HR) were statistically significant for RVF (HR = 8.9, P < 0.001), BVF (HR = 5.2, P = 0.006), and NF-LC (HR = 4.9, P = 0.002) groups. The NF-LC group remained significantly predictive of mortality after adjusting for RVEF, native T1, and PH diagnosis (P = 0.0046). CONCLUSION: We identified five CMR-defined cardiac SSc phenotypes that did not co-segregate with clinical data and had distinct outcomes, offering opportunities for a more precision-medicine based management approach

Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration, Contents identical with the version published in Pramana - J. Physic

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Design and dynamic simulation of mobile manipulators incorporating tribological analysis of 16MnCr5 and EN19 steels.

Search and Rescue (SAR) robotics is a growing research area in spite of which reports show that heavy equipment like excavators are still used in SAR operations despite their unsuitability. Literature reveals the need for new designs for application-specific manipulators in time-critical SAR operations. To this end, the Computer Aided Design (CAD)-Multibody dynamics (MBD) simulation technique was applied instead of traditional numerical modelling and roofs-of-concept for two types for manipulators, i.e. anthropoid and complex closed-loop manipulators are presented. The combined friction model (CFM) was incorporated into this simulation considering the importance of friction as a tribological component affecting the dynamic performance of such mobile manipulators. To surmount the limitations of friction models, scaled-down tribological experiments were conducted to determine the coefficient of friction (COF) for two contact geometries - sliding cylinder and sliding pin, selected as approximations of manipulator joint contact. Oil lubricant was used to generate reference COF characteristics against which COF of grease-lubricated contacts were compared, and oil-lubrication showed better COF than grease-lubrication. However, oil is a fluid and it cannot be used in the application environment. Subsequently, the effect of nickel alumina nanocomposite coating on COF deposited on 16MnCr5 specimens using pulse electrodeposition (PED) was analysed. The results showed that this coating only reduced the COF by 3.1% compared to uncoated specimens in sliding cylindrical contacts, while in the case of sliding pin contacts the coating proved to be detrimental with a 22.1% increase in COF. The values of COF were used in a linear model for computing joint torque. Results of surface characterisation carried out using white light interferometry, digital microscopy and scanning electron microscopy substantiate the COF measurements. Microhardness of the surface was also analysed and showed that coatings improved the surface hardness by 19.7% to 55.9%. Therefore, this work contributes to the SAR robotics through design and simulation, and tribology

ANALYSIS OF GREASE LUBRICATED ISOVISCOUS-ELASTIC POINT CONTACTS

ABSTRACT Greases generally behave as shear-thinning or pseudo-plastic fluids-their viscosity reduces under shear i.e. with sufficient shear the viscosity of grease approaches that of the base lubricant. By this behaviour grease may be considered as a plastic fluid. Numerical solution of the modified Reynolds equation for grease for point contacts remains challenging, despite the advent of powerful computational techniques and platforms. Grease lubricated concentrated point contacts are analysed under isothermal conditions. Grease is seen to provide better lubrication in comparison with oil lubricant, thus protracting the life of the contact conjunction. Operating conditions have been defined by dimensionless control parameters. The asymptotic behaviour of grease allows for the development of film thickness equations. From the results of the numerical method, extrapolated equations for grease film thickness in iso-viscous elastic regime lubrication is developed using the dimensionless parameters

State of the art in excavators

Survey of literature has revealed research on excavators in trajectory analysis, modeling, control, soil-tool interaction, energy efficiency, and simulators. Kinematics of excavators has largely remained unchanged over time. Dynamic models of 3 degree of freedom (DOF) manipulator have been applied in literature. Soil-tool interaction models are becoming computationally less demanding and more accurate, for predicting interaction forces of end effector or bucket. Control of excavators through adaptive/robust control and high level behavioral control may fully automate such systems. Simulators provide platforms for testing and operator training and require dynamically accurate models. Even though much research has occurred in different areas of excavators, still fully automated excavators are rare. This paper investigates the state of art in excavators and reports the recent progress. The aim of this paper is to identify gaps in existing technology and the demands on excavators with the idea of suggesting future trends in research and as a reference for new research

Benign metastasizing leiomyoma causing spinal cord compression

Background: Leiomyoma as a cause of cord compression is extremely rare. To our knowledge this is the first report of a dural-based leiomyoma and second report of a leiomyoma causing cord compression. Case description: A 38-year-old female renal transplant recipient presented with features of cervical cord compression. On imaging and at surgery, the tumor was mistaken for a neurofibroma. A cervical laminectomy and near total excision of the tumor was done. She did well in the postoperative period but presented 5 months later with thoracic empyema leading to septicemia and her demise. Ultrasound examination and autopsy showed leiomyomas in many other sites including the uterus. Conclusions: The presence of extrauterine and uterine leiomyomas is a curious condition termed as "benign metastasizing leiomyoma." As our patient was on immunosuppressant therapy following a renal transplant, it might have predisposed her to this rare condition with multifocal tumors