Sensory processing and world modeling for an active ranging device

In this project, we studied world modeling and sensory processing for laser range data. World Model data representation and operation were defined. Sensory processing algorithms for point processing and linear feature detection were designed and implemented. The interface between world modeling and sensory processing in the Servo and Primitive levels was investigated and implemented. In the primitive level, linear features detectors for edges were also implemented, analyzed and compared. The existing world model representations is surveyed. Also presented is the design and implementation of the Y-frame model, a hierarchical world model. The interfaces between the world model module and the sensory processing module are discussed as well as the linear feature detectors that were designed and implemented

Cell cycle protein expression in AIDS-related and classical Kaposi's sarcoma

Kaposi�s sarcoma (KS) is a peculiar vascular neoplasm that occurs mainly in elderly Mediterranean men and patients with acquired immunodeficiency syndrome (AIDS). The current literature indicates that KS is initiated by the human herpes virus 8 (HHV8) as a reactive polyclonal process but with deregulation of oncogene and tumour suppressor genes, it can progress to a true malignancy with monoclonality. Clinically, classical KS often presents as an indolent disease affecting mainly the lower extremities whereas AIDS-related KS has no site predilection and can progress rapidly with systemic involvement. Histologically, KS can be classified into patch, plaque and nodular stages. Interestingly, classical and AIDS-related KS are indistinguishable histologically and this suggests that AIDS-related KS and classical KS might be initiated by a common aetiology but given their different clinical courses, they may progress through different mechanisms. In view of the importance of the cell cycle proteins in the development and progression of many human malignancies, this thesis aims to examine the role of these proteins in the progression of the two main clinical subtypes of KS. The cell cycle protein expressions in a cohort of 47 patients with KS with welldocumented clinical and histological features were studied. Using a monclonal antibody against the latent nuclear antigen-1 molecule of HHV8, HHV8 was detected in 78% of the cases. The more advanced nodular lesions were found to have a higher level of proliferative activity as measured by the proliferation x marker, Ki-67. This suggests it is valid to use the histological specimens as a tumour progression model of KS. The role of the Rb/cyclin D1/p16 pathway was examined. The more advanced nodular stage KS lesions were more likely to be positive for cyclin D1, suggesting that cyclin D1 is important in the progression from patch stage to nodular stage. p16 acts as a tumour suppressor and it has an inhibitory effect on cyclin D1. The p16 expression rate was low in early stage KS but high in the more advanced lesions. It seems that reduced p16 expression occurs early in KS and may be important in its development. The rate of Rb expression, on the other hand, did not differ significantly among the histological subtypes. The results revealed the significant role of the Rb/cyclin D1/p16 pathway in the progression of KS. Of the mitotic cyclins examined, cyclin A expression was correlated with the advanced tumor stage. The rate of p34cdc2 expression was high in the lesions and there was no correlation with histological stage. This suggests that p34cdc2 is important in the early development of the tumour but not necessarily in its progression. Along the p53-apoptotic pathway, mutant p53 expression was significantly more common in the nodular stage. The cyclin G1 (a protooncogene, one of the target genes of p53) expression also paralleled that of mutant p53 with the majority of the KS lesions showing cyclin G1 expression and significant xi correlation between advanced histological stage and increasing rate of cyclin G1 expression. These findings suggest that progression along the p53 pathway may be important in the advanced stage development of KS. On the other hand, expression of the CDK inhibitor, p27, a protein that normally negatively regulates cyclin G1, was reduced in nodular KS. These findings suggest that some KS lesions may progress through a deregulated or abnormal p53 pathway. There were correlations between cyclin D1, cyclin A, cyclin G1, mutant p53 and negative HIV status. The findings suggest that components of both the Rb/cyclin D1/p16 and p53-apoptotic pathways are important in the progression of classical KS. Rb protein was the only cell cycle protein whose rate of expression correlated significantly with HHV8 status in KS. The majority of HHV8 positive lesions were also positive for Rb protein, unlike HHV8 negative lesions. This suggests that some of the HHV8 negative lesions can progress through a defective Rb pathway whereas the role of Rb in the progression may not be as important in the HHV8 positive lesions. This was an unexpected finding given that one of the postulated mechanisms of tumour initiation by the HHV8 virus is via the viral cyclin it produces. The viral cyclin produced by HHV8 acts through the Rb pathway much the same as cyclin D1 and one would have expected that HHV8 positive cases are less likely to be positive for the Rb protein. In summary, the majority of the KS lesions examined in this thesis show HHV8 infection. The Rb/cyclin D1/p16 pathway appears to be important in the progression of the different stages of KS and expression of the proteins involved in the p53 pathway were found to be important in the advanced stages of the development of KS. There were differential expressions of cell cycle proteins between AIDS-related and classical KS, and between HHV8 positive and HHV8 negative lesions. The findings also provided some clues to the possible mechanisms of development in KS lesions that were not initiated by HHV8

Presumed choroidal metastasis from soft tissue myoepithelial carcinoma

Purpose: To report a case of presumed choroidal metastasis from soft tissue myoepithelial carcinoma and highlight challenges in its diagnosis. Observations: A 52-year-old man was referred with a two-week history of photopsia in his left eye. His background medical history included known soft tissue myoepithelial carcinoma metastatic to his bone, lung, liver and chest wall. A large, raised, yellow choroidal lesion was identified nasal to and abutting the optic disc. This lesion demonstrated growth 1 month after presentation. The patient died with widespread metastatic disease 5 months after initial presentation. Conclusion and importance: Soft tissue myoepithelial carcinoma can rarely metastasise to the choroid and present as a rapidly-growing, yellow, echodense tumour with serous retinal detachment. MRI brain can assist in tumour evaluation and monitoring progression, while immunoperoxidase stains and molecular testing can assist with diagnosis. The condition has an aggressive natural history and poor prognosi

Economics of neuraminidase inhibitor stock piling for pandemic influenza, Singapore.

We compared strategies for stock piling neuraminidase inhibitors to treat and prevent influenza in Singapore. Cost-benefit and cost-effectiveness analyses, with Monte Carlo simulations, were used to determine economic outcomes. A pandemic in a population of 4.2 million would result in an estimated 525-1,775 deaths, 10,700-38,600 hospitalization days, and economic costs of 0.7 dollars to 2.2 billion Singapore dollars. The treatment-only strategy had optimal economic benefits: stock piles of antiviral agents for 40% of the population would save an estimated 418 lives and 414 million dollars, at a cost of 52.6 million dollars per shelf-life cycle of the stock pile. Prophylaxis was economically beneficial in high-risk subpopulations, which account for 78% of deaths, and in pandemics in which the death rate was >0.6%. Prophylaxis for pandemics with a 5% case-fatality rate would save 50,000 lives and 81 billion dollars. These models can help policymakers weigh the options for pandemic planning

A new topology of the HK97-like fold revealed in Bordetella bacteriophage by cryoEM at 3.5 A resolution.

Bacteriophage BPP-1 infects and kills Bordetella species that cause whooping cough. Its diversity-generating retroelement (DGR) provides a naturally occurring phage-display system, but engineering efforts are hampered without atomic structures. Here, we report a cryo electron microscopy structure of the BPP-1 head at 3.5 Å resolution. Our atomic model shows two of the three protein folds representing major viral lineages: jellyroll for its cement protein (CP) and HK97-like ('Johnson') for its major capsid protein (MCP). Strikingly, the fold topology of MCP is permuted non-circularly from the Johnson fold topology previously seen in viral and cellular proteins. We illustrate that the new topology is likely the only feasible alternative of the old topology. β-sheet augmentation and electrostatic interactions contribute to the formation of non-covalent chainmail in BPP-1, unlike covalent inter-protein linkages of the HK97 chainmail. Despite these complex interactions, the termini of both CP and MCP are ideally positioned for DGR-based phage-display engineering. DOI: http://dx.doi.org/10.7554/eLife.01299.001

Management of Worsening Aortic Dilation and Insufficiency in a 20-Week Pregnant Woman: A Case Report

Preexisting aortic disease can worsen during pregnancy as physiologic hemodynamic changes evolve. At a large academic institution, a patient with a remote history of vasculitis presented with a second trimester pregnancy with increasing aortic dilatation and aortic insufficiency. Extensive obstetric discussions encompassed maternal cardiac risks from continuing the pregnancy and fetal risks from maternal cardiac intervention. This patient desired termination of pregnancy to avoid further complications and to expedite surgical aortic repair

Effects of Tai Chi on the quality of life, mental wellbeing, and physical function of adults with chronic diseases: Protocol for a single-blind, two-armed, randomised controlled trial

Introduction Quality of life (QoL), mental wellbeing, and physical function are often diminished among people with chronic disease. Tai Chi is a moderate form of exercise that may be effective in improving chronic disease management. This protocol paper outlines a trial to determine the therapeutic effects of a Tai Chi program on chronic disease management. Methods and analysis This study will be a pilot, interventional, single-blind, two-armed, randomised, parallel, and controlled trial involving a 12-week Tai Chi program for Australian adults. Forty people aged 18 years and older, diagnosed with one or more chronic disease from general community will be recruited. All participants will be randomised to either a 12-week Tai Chi program or a waiting list control group. The Tai Chi program will involve 12 weeks of group Tai Chi sessions, with 45 minutes per session, twice a week. The primary outcome will be QoL as measured by mean scores on the 12-item Short Form Health Survey (SF-12v2) and the EuroQoL (EQ-5D). The secondary outcomes will include anxiety as measured by mean score on the generalised anxiety disorder 7 (GAD-7) survey; depression as measured by mean score on the patient health questionnaire (PHQ-9); work productivity and activity assessment (WPAI:SHP); pain (if any) as measured by mean scores on the visual analogue scale (VAS) and the McGill pain questionnaire (MPQ). These primary and secondary outcomes will be self-administered via two online assessments prior to (T0) and post-intervention (T1). Objective measures as additional secondary outcomes, will also be carried out by the research team including flexibility as measured by the finger to floor distance (FFD); obesity as measured by mean scores on body mass index (BMI); vital signs (blood pressure, heart rate, respiratory rate, temperate, and oxygen saturation) as measured by a blood pressure monitor, tympanic, and pulse oximetry device, and these outcomes will be measured at T0 and T1 in the ECU Holistic Health Research Clinic. People diagnosed with pre-diabetes or diabetes, their glycosylated haemoglobin (HbA1C) and fasting (before breakfast) blood glucose level (BGL) will also be measured via test kits at T0 and T1 in the clinic. Linear mixed modelling will be conducted to assess changes in outcomes. Statistical significance will be set at an alpha level of 0.05 with a medium effect size. All analyses will be conducted using R version 4.1. Qualitative data will be analysed using template thematic analysis. Ethics and dissemination Ethical approval has been obtained from the Edith Cowan University (ECU) Human Research Ethics Committee (2021-03042-WANG). Research findings will be disseminated to the public, health professionals, researchers, and healthcare providers through conference presentations, lay summaries, and peer-reviewed publications. This study will provide an updated evidence on a safe, sustainable, and inexpensive non-pharmacological approach in the management of chronic disease, the number one burden of disease in Australia

INVESTIGATING THE POSSIBILITY FOR IS/IT TO SUPPORT THE DELIVERY OF CHINESE MEDICINE

As Chinese medicine (CM) has increased in popularity globally it now becomes imperative to investigate ways in which safe, efficient, effective and evidence-based approaches might be adopted into CM practice. In the case of western or more traditional healthcare delivery practice, IS/IT is often adopted and employed to assist in this regard and thus this paper examines how IS/IT might be used to support the delivery of CM. In particular, the paper investigates how IS/IT tools and techniques might be used in supporting CM clinics daily processes and thereby bring greater value to a country’s healthcare. In doing so, this paper studies the current global CM situation and provides a solid foundation for how to design and develop an enterprise wide CM clinical management system

Assessing Glucose Uptake through the Yeast Hexose Transporter 1 (Hxt1)

The transport of glucose across the plasma membrane is mediated by members of the glucose transporter family. In this study, we investigated glucose uptake through the yeast hexose transporter 1 (Hxt1) by measuring incorporation of 2-NBDG, a non-metabolizable, fluorescent glucose analog, into the yeast Saccharomyces cerevisiae. We find that 2-NBDG is not incorporated into the hxt null strain lacking all glucose transporter genes and that this defect is rescued by expression of wild type Hxt1, but not of Hxt1 with mutations at the putative glucose-binding residues, inferred from the alignment of yeast and human glucose transporter sequences. Similarly, the growth defect of the hxt null strain on glucose is fully complemented by expression of wild type Hxt1, but not of the mutant Hxt1 proteins. Thus, 2-NBDG, like glucose, is likely to be transported into the yeast cells through the glucose transport system. Hxt1 is internalized and targeted to the vacuole for degradation in response to glucose starvation. Among the mutant Hxt1 proteins, Hxt1N370A and HXT1W473A are resistant to such degradation. Hxt1N370A, in particular, is able to neither uptake 2-NBDG nor restore the growth defect of the hxt null strain on glucose. These results demonstrate 2-NBDG as a fluorescent probe for glucose uptake in the yeast cells and identify N370 as a critical residue for the stability and function of Hxt1

Using IS/IT to Support the Delivery of Chinese Medicine: The Design of a Chinese Medicine Clinic System

Using Information System/Information Technology (IS/IT) in Chinese Medicine (CM) has not been discussed much, if at all, in the literature. This is unlike the numerous references to the role for IS/IT to support various aspects of western medicine practice. Though the diagnosis and treatments between western medicine and CM are different, the clinical processes are similar. Thus, we believe that by implementing IS/IT system solutions, CM practice can also enjoy many benefits. CM practice relies on expert knowledge, hence applying knowledge management (KM) concepts to any proposed Chinese Medicine Clinic System (CMCS) is a necessary critical factor in the design of suitable IS/IT solutions in this context. This paper serves to identify a role for IS/IT in assisting CM clinic daily key processes as well as identify key system features and functions for a suitable CMCS