Progress Towards Untethered Autonomous Flight of Northeastern University Aerobat

State estimation and control is a well-studied problem in conventional aerial vehicles such as multi-rotors. But multi-rotors, while versatile, are not suitable for all applications. Due to turbulent airflow from ground effects, multi-rotors cannot fly in confined spaces. Flapping wing micro aerial vehicles have gained research interest in recent years due to their lightweight structure and ability to fly in tight spaces. Further, their soft deformable wings also make them relatively safer to fly around humans. This thesis will describe the progress made towards developing state estimation and controls on Northeastern University's Aerobat, a bio-inspired flapping wing micro aerial vehicle, with the goal of achieving untethered autonomous flight. Aerobat has a total weight of about 40g and an additional payload capacity of 40g, precluding the use of large processors or heavy sensors. With limited computation resources, this report discusses the challenges in achieving perception on such a platform and the steps taken towards untethered autonomous flight.Comment: Accepted as final report for Master's thesis towards a Master of Science in Robotic

How Strong a Kick Should be to Topple Northeastern's Tumbling Robot?

Rough terrain locomotion has remained one of the most challenging mobility questions. In 2022, NASA's Innovative Advanced Concepts (NIAC) Program invited US academic institutions to participate NASA's Breakthrough, Innovative \& Game-changing (BIG) Idea competition by proposing novel mobility systems that can negotiate extremely rough terrain, lunar bumpy craters. In this competition, Northeastern University won NASA's top Artemis Award award by proposing an articulated robot tumbler called COBRA (Crater Observing Bio-inspired Rolling Articulator). This report briefly explains the underlying principles that made COBRA successful in competing with other concepts ranging from cable-driven to multi-legged designs from six other participating US institutions

Autopathogenic T Helper Cell Type 1 (Th1) and Protective Th2 Clones Differ in Their Recognition of the Autoantigenic Peptide of Myelin Proteolipid Protein

We previously generated a panel of T helper cell 1 (Th1) clones specific for an encephalitogenic peptide of myelin proteolipid protein (PLP) peptide 139–151 (HSLGKWLGHPDKF) that induces experimental autoimmune encephalomyelitis (EAE) upon adoptive transfer. In spite of the differences in their T cell receptor (TCR) gene usage, all these Th1 clones required W144 as the primary and most critical TCR contact residue for the activation. In this study, we determined the TCR contact residues of a panel of Th2/Th0 clones specific for the PLP peptide 139–151 generated either by immunization with the PLP 139–151 peptide with anti– B7-1 antibody or by immunization with an altered peptide Q144. Using alanine-substituted peptide analogues of the native PLP peptide, we show that the Th2 clones have shifted their primary contact residue to the NH2-terminal end of the peptide. These Th2 cells do not show any dependence on the W144, but show a critical requirement for L141/G142 as their major TCR contact residue. Thus, in contrast with the Th1 clones that did not proliferate to A144-substituted peptide, the Th2 clones tolerated a substitution at position 144 and proliferated to A144 peptide. This alternative A144 reactive repertoire appears to have a critical role in the regulation of autoimmune response to PLP 139–151 because preimmunization with A144 to expand the L141/G142-reactive repertoire protects mice from developing EAE induced with the native PLP 139–151 peptide. These data suggest that a balance between two different T cell repertoires specific for same autoantigenic epitope can determine disease phenotype, i.e., resistance or susceptibility to an autoimmune disease

Positive psychology and Indian psychology: Birds of the same feather

Positive psychology and Indian psychology share similar concerns regarding human life. But Indian psychology has more to offer towards our understanding of happiness and well-being than what Positive psychology can at this point of time, because of latter�s paradigmatic limitations. This commentary draws attention to certain shortcomings of the target article: (a) in presenting the contemporary Positive psychology perspective; (b) in conceptualizing IP with reference to its epistemological position; (c) and in equating certain concepts from PP and IP and their implications

Bisphosphonates, Menopausal Hormone Therapy and Risk Factors for Breast Cancer in Australia

In Australian women, breast cancer is the second most commonly diagnosed cancer after non-melanoma skin cancers. The use of Menopausal Hormone Therapy (MHT) is an important breast cancer risk factor in postmenopausal women. Prior to findings from large-scale studies on the benefits and harms of MHT, it was used widely, and often, for the management of chronic conditions attributed to menopause, along with its primary use for menopausal symptoms. However, following the availability of such evidence from the Women’s Health Initiative (WHI) trial and other studies in 2002-2003, recommendations for MHT use became more specific and a substantial drop in MHT prescribing was noted in many settings. Although MHT use in Australia dropped substantially after 2002, a significant proportion of women continue to use MHT. Quantifying the breast cancer risks associated with this potentially modifiable risk factor using contemporaneous data in Australian women constitutes an important part of this thesis. Furthermore, a number of other reproductive and lifestyle factors have been found to be associated with breast cancer risk, but these may have differing associations with breast cancer in pre- and postmenopausal women. As an important background to the assessment of MHTassociated risk, these other risk factor associations were quantified in Australian women. Menopause accelerates age-related bone loss which often leads to osteoporosis. Although MHT prevents fracture, because of its generally unfavourable risk profile, when used long-term, it is not recommended first-line for prevention or management of osteoporosis. Bisphosphonates (a class of anti-bone resorptive drugs) are the recommended first-line therapy for osteoporosis. Concurrent with the drop in MHT use after 2002, a substantial increase in bisphosphonate prescribing was noted in many settings. These data raised the possibility that bisphosphonates were replacing MHT, probably as an indirect effect of the WHI trial findings and subsequent revisions to recommendations which restricted its use primarily for short-term menopausal symptom relief. However, among postmenopausal women, evidence-based guidelines and health technology assessments suggest somewhat different target age groups for these two groups of medications. MHT is recommended for relief from vasomotor symptoms around the time of menopause, whereas bisphosphonate use is recommended to women who are at a significant risk of osteoporosis-related fractures, which usually occur a couple of decades after menopause. This thesis examines changes in MHT and bisphosphonate prescribing, in postmenopausal Australian women and a comparable group of women from Manitoba, Canada. The main aims of this thesis are to 1) quantify the relationship between reproductive and lifestyle factors, and breast cancer risk in pre- and postmenopausal Australian women, 2) quantify breast cancer risks associated with MHT use, and to test for this association for specific subtypes of breast cancer, in postmenopausal Australian women and 3) investigate changes in prescribing of MHT and bisphosphonates in women over the age of 50 from Australia and Manitoba, Canada, in relation to the age of the users and the recommendations for use in both settings, over the period 1996-2008. To address Aims 1 and 2, a review of the literature was performed to inform multivariable breast cancer risk factor analyses, which were carried out separately in premenopausal (523 cases/176 controls) and postmenopausal (1276 cases/865 controls) Australian women. Odds ratios for breast cancer associated with MHT use and other risk factors were obtained through multivariable regression analyses using data from an all cancer case-spouse control study-The NSW Cancer Lifestyle and EvAluation of Risk (CLEAR) study. Pathology data on hormone and epidermal growth factor receptor status for a subset of the breast cancer cases (n= 419) was obtained and used to estimate MHTassociated risks for specific breast cancer subtypes. For Aim 3, overall and age-specific MHT and bisphosphonate prescribing patterns in women aged ≥ 50 years, from Australia and Manitoba, Canada were described. In premenopausal women, increased age and family history of breast cancer were found to be associated with increased breast cancer risk, whereas breastfeeding was associated with a reduction in risk. Although limited by sample size, my findings for other factors were generally compatible with the literature. In postmenopausal women, reproductive factors such as nulliparity and increased age at first birth, and increased BMI were found to be associated with increased breast cancer risk. Current use of MHT was found to be associated with a doubling of breast cancer risk; risks were generally higher in users of oestrogen-progestagen combination therapy compared to oestrogen-only MHT, although heterogeneity by type of preparation was not evident. MHT use was associated specifically with an increased risk of developing oestrogen- and progesterone- receptor - positive breast cancers, consistent with the hypothesis that the hormone effects are receptor-mediated. The analyses using ecological data on dispensed medications confirmed that concurrent and substantial drops in MHT prescribing and increases in bisphosphonate prescribing occurred in Australia and Manitoba, Canada, but they occurred in different age-groups of postmenopausal women, in both settings. The drop in MHT prescribing which occurred in women in their fifties and sixties is in agreement with the post-2002 recommendations for more specific and targeted use. The increase in bisphosphonate prescribing in women in their seventies and eighties suggest that their use was generally consistent with recommendations, during the time period studied. A total of 13% of Australian women aged 50-69 currently use MHT with ~75% of them using MHT for ≥ 5 years. The MHT-associated risks estimated in this study provide important information to Australian women and provide additional support to the current guidance by regulatory authorities which recommend that MHT use should be limited to the shortest time possible, in women with moderate to severe menopausal symptoms, who are aware of the risks and benefits

An Epidemiologicial overview of the relationship between hormone replacement therapy and breast cancer.

Large-scale randomized clinical trials and observational studies have consistently found thatt use of hormone replacement therapy (HRT) increases the risk of breast cancer. More recently, ecological studies have shown correlations between dramatic reductions in use of HRT in many countries, and declines in the rates of breast cancer in older women. Meta-analyses of data from the trials and observational studies show that the increase in breast cancer risk is greater for combined estrogen-progestin therapies compared with estrogen alone; that for both types of preparation, breast cancer risk increases with duration of use; and that the risks decerase relatively quickly after cessation of use. For both estorgen-only and combined therapies, the risk of breast cancer is higher if therapy is initiated close to the time of menopause, relative to the risks in women starting HRT later. Most drug regulatory authorities currently recommend that HRT be prescribed only to fully informed women who have moderate-to-servere menopausal symptomes, for the shortest duraction possible; and it is recommended that the need for therapy be reviewed at least every 6-12 months

Factorial hypercube designs for spatial correlation regression

The problem of generating a good experimental design for spatial correlation regression is studied in this paper. The quality of fit generated by random designs, Latin hypercube designs and factorial designs is studied for a particular response surface that arises in inkjet printhead design. These studies indicate that the quality of fit generated by spatial correlation models is highly dependent on the choice of design. A design strategy that we call 'factorial hypercubes' is introduced as a new method. This method can be thought of as an example of a more general class of hybrid designs. The quality of fit generated by these designs is compared with those of other methods. These comparisons indicate a better fit and less numerical problems with factorial hypercubes.

Menopausal hormone therapy: a systematic review of cost-effectiveness evaluations

Abstract Background Several evaluations of the cost-effectiveness (CE) of menopausal hormone therapy (MHT) have been reported. The aim of this study was to systematically and critically review economic evaluations of MHT since 2002, after the Women’s Health Initiative (WHI) trial results on MHT were published. Methods The inclusion criteria for the review were: CE analyses of MHT versus no treatment, published from 2002-2016, in healthy women, which included both symptom relief outcomes and a range of longer term health outcomes (breast cancer, coronary heart disease, stroke, fractures and colorectal cancer). Included economic models had outcomes expressed in cost per quality-adjusted life year or cost per life year saved. MEDLINE, EMBASE, Evidence-Based Medicine Reviews databases and the Cost-Effectiveness Analysis Registry were searched. CE evaluations were assessed in regard to (i) reporting standards using the CHEERS checklist and Drummond checklist; (ii) data sources for the utility of MHT with respect to menopausal symptom relief; (iii) cost derivation; (iv) outcomes considered in the models; and (v) the comprehensiveness of the models with respect to factors related to MHT use that impact long term outcomes, using breast cancer as an example outcome. Results Five studies satisfying the inclusion criteria were identified which modelled cohorts of women aged 50 and older who used combination or estrogen-only MHT for 5-15 years. For women 50-60 years of age, all evaluations found MHT to be cost-effective and below the willingness-to-pay threshold of the country for which the analysis was conducted. However, 3 analyses based the quality of life (QOL) benefit for symptom relief on one small primary study. Examination of costing methods identified a need for further clarity in the methodology used to aggregate costs from sources. Using breast cancer as an example outcome, risks as measured in the WHI were used in the majority of evaluations. Apart from the type and duration of MHT use, other effect modifiers for breast cancer outcomes (for example body mass index) were not considered. Conclusions This systematic review identified issues which could impact the outcome of MHT CE analyses and the generalisability of their results. The estimated CE of MHT is driven largely by estimates of QOL improvements associated with symptom relief but data sources on these utility weights are limited. Future analyses should carefully consider data sources and the evidence on the long term risks of MHT use in terms of chronic disease. This review highlights the considerable difficulties in conducting cost-effectiveness analyses in situations where short term benefits of an intervention must be evaluated in the context of long term health outcomes.Cancer Council NS