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Secure network-index code equivalence: extension to non-zero error and leakage
No full textA linear code equivalence between index coding and network coding was shown by El Rouayheb et al., which establishes that for any index-coding instance, there exists a network-coding instance for which any index code can be mapped to a suitable network code, and vice versa. Similarly, for any network-coding instance, there exists an index-coding instance for which a similar code equivalence can be constructed. Effros et al. extended the equivalence to include non-linear codes. Subsequently, we extended the code equivalence to the secure communication setting in the presence of an eavesdropper, in which we impose perfect decodability and secrecy. In this paper,
we generalise the equivalence between secure index coding and secure network coding to include non-zero decoding error and non-zero leakage
Identification of regulatory genes controlling cell wall invertase expression in Arabidopsis reproductive organs
No full textIn higher plants, sucrose (Suc) is synthesised in source leaves for translocation through phloem to non-photosynthetic organs (sinks). Upon reaching sink cells, Suc is often hydrolysed by cell wall invertase (CWIN) into glucose (Glc) and fructose (Fru), as building blocks, energy source and signalling molecules for growth and development. Despite the central roles of CWIN in assimilate partitioning, the upstream molecular machineries that control CWIN expression remain largely unknown. This PhD project therefore aims to identify the ‘master’ regulatory genes controlling CWIN expression in reproductive organs using Arabidopsis as a model. We hypothesised that CWIN gene expression is possibly regulated by some transcription factors (TFs) and small RNAs (sRNAs). As the first step, a suite of bioinformatics tools was employed to search for candidate genes controlling the expression of CWIN2 and CWIN4, which are predominantly expressed in Arabidopsis reproductive organs. The analyses identify 18 TF genes and one microRNA (miRNA) as putative regulators of CWIN2 or CWIN4. Among them, MYB21, ARF6, ARF8, AP3 and CRC were confirmed to be regulators for CWIN gene expression based on the finding that their mutants exhibited reduced mRNA level of CWIN2 or CWIN4. One miRNA, miR3932, displayed an inverse expression pattern and an imperfect sequence match with CWIN2, indicating its possible involvement in degrading CWIN2 RNA. Due to time constraint, further studies were focused on examining the roles of candidate TFs in modulating the expression of the CWIN genes. Measurement of GUS signal in the mutants of the confirmed TF genes transformed with ProCWIN2/4:GUS revealed that MYB21, ARF6 and ARF8 mainly control CWIN2 expression in anthers/pollen, whereas MYB21, ARF6, ARF8, AP3 and CRC appear to regulate CWIN4 expression in nectaries and/or petals. Indeed, over-expression of AP3 increased CWIN2 and CWIN4 expression in the inflorescence, Furthermore, increasing the expression of CWIN4 driven by ARF8, promoter partially recovered arf8-3 short silique phenotype. Finally, transient expression of ARF6 and CRC induced CWIN2 and CWIN4 transcript levels, respectively, in Arabidopsis leaf protoplasts. Based on the results obtained, we proposed a model on the molecular network controlling CWIN2 and CWIN4 expression by MYB21, ARF6, ARF8, AP3, CRC and possible hormone pathways. Understanding the regulatory mechanisms controlling CWIN gene expression fills a major knowledge gap in the area. It also provides an opportunity to genetically modify the expression of CWIN2 and/or CWIN4 or related genes in reproductive organs by manipulating their regulatory genes. This approach has the potential to significantly improve the partitioning of assimilates towards plant reproductive organs for achieving high crop yield
Data-driven modeling of a coupled electric drives system using regularized basis function Volterra kernels
No full textIn this paper, we consider the problem of data-driven modeling for systems containing nonlinear sensors. The issue is explored via an established nonlinear benchmark in the system identification community, referred to as the “coupled electric drives.” In the benchmark system, nonlinearity emerges in the pulse transducer used to measure the angular velocity of a pulley, which is invariant to the direction of rotation. In order to model the nonlinear dynamics without the use of extensive prior knowledge, we estimate a nonparametric Volterra series model using a regularized basis function approach. While the Volterra series is typically an impractical modeling tool due to the large number of parameters required, we obtain accurate models using only a short estimation dataset, by directly regularizing the basis function expansions of each Volterra kernel in a Bayesian framework
Draft genome sequence of microbacterium esteraromaticum MM1, a bacterium that hydrolyzes the organophosphorus pesticide fenamiphos, isolated from golf course soil
No full textIn this study, we report the first draft genome sequence of Microbacterium esteraromaticum MM1, isolated from golf course soil in South Australia. The genome possesses genes for the hydrolysis of organophosphorus (OP) pesticides and polycyclic aromatic hydrocarbon (PAH) degradation
Resveratrol supplementation reduces pain experience by postmenopausal women
No full textObjective: Pain is a common complaint among postmenopausal women. It has been postulated that vascular dysfunction caused by estrogen decline at menopause plays a key role in the initiation and progression of degradative joint disease, namely age-related osteoarthritis. We evaluated whether supplementation with resveratrol, a phytoestrogen, could improve aspects of well-being such as chronic pain that is commonly experienced by postmenopausal women. Methods: A 14-week randomized, double-blind, placebo-controlled intervention with trans-resveratrol (75mg, twice daily) was conducted in 80 healthy postmenopausal women. Aspects of well-being, including pain, menopausal symptoms, sleep quality, depressive symptoms, mood states, and quality of life were assessed by Short form-36 at baseline and at the end of treatment. Rating scales were averaged to provide a composite score representing overall well-being. Cerebral vasodilator responsiveness to hypercapnia was also assessed as a surrogate marker for cerebrovascular function. Results: Compared with placebo treatment, there was a significant reduction in pain and an improvement in total well-being after resveratrol supplementation. Both benefits, including measures of quality of life, correlated with improvements in cerebrovascular function. Conclusions: Our preliminary findings indicate potential for resveratrol treatment to reduce chronic pain in age-related osteoarthritis. Resveratrol consumption may also boost perceptions of well-being in postmenopausal women. Further investigation to elucidate underlying mechanisms is warranted
Family involvement in ownership, control, management and firm performance: empirical evidence from Viet Nam
No full textThe question of how family affects firm performance remains open for debate. Despite growing attention to family business research, results are mixed regarding the effects of of family involvement on family firm performance. The dissertation adopts various theoretical paradigms to reconcile empirical inconsistencies by examining both negative and positive effects of family involvement. The adopted paradigms include the familiness perspective constructed from the resource- based view; the socioemotional wealth perspective, an emerging construct with a potential to become a dominating theory of family firms; agency and stewardship theories. Using proxy data for 198 family firms listed on Ho Chi Minh City and Ha Noi stock exchange markets, multiple quadratic regressions are employed to assess the nonlinear effects of family involvement components on firm performance as measured by ROA and Tobin’s Q. Consistent with the author's conjecture, the study finds that the relationships between family involvement in ownership, board of directors and firm performance are curvilinear. The study also reveals the excessive family involvement on the board of directors is negatively related to firm performance. These findings suggest that unchallenged control might lead to expropriation for the private benefit of controlling families, and family firms' best performances are associated with moderate levels of ownership and optimal board structures with the involvement of both family and nonfamily members. Contrary to the author's predictions, the research results reject a curvilinear relationship between family involvement in management and firm performance. The results also reject moderation effects of multi-generational and family Chair/CEO spousal involvement on the influence of family involvement in ownership on firm performance. However, the study finds family involvement in management and multi-generational involvement are negatively associated with firm value. These findings shed light on the effects of family management; and familial altruism and complexity in multi-generation family firms.
The research makes an important contribution to the growing knowledge of components of family involvement in the family business, further understanding of familiness and socioemotional wealth constructs. The findings suggest corporate governance mechanisms should promote a balanced board of directors and top management team with representation of family and nonfamily members to enhance the value of family businesses
Measuring the progress of a recovery process after an earthquake: the case of L'aquila, Italy
No full textAfter the earthquake in 2009, L'Aquila (Italy) began a recovery process characterized by a delay in the reconstruction of the city center. Between 2010 and 2014 a recovery index was formulated based on spatial indicators, such as building condition and building use, to measure the progress of the recovery process in L'Aquila. Eight years after the earthquake, the work presented in this paper was used to update the recovery index, not only by measuring the progress of the recovery in L'Aquila but also by validating the usefulness of the proposed recovery index. To achieve this objective, the current research considered the same set of spatial indicators that were used to determine the progress of the recovery in L'Aquila by 2010, 2012, and 2014 in the revaluation of the expert criteria. It was found that in 2016 the number of reconstructed buildings and buildings under ongoing construction had significantly increased and the number of buildings with residential and commercial use had increased along the main roads. While progress was observed in the overall building condition, there was no significant progress in the building use. This poses several questions about how the recovery process can contribute to the return of the inhabitants to the city center of L'Aquila. The paper concludes that the proposed recovery index is useful for identifying the spatial pattern of the recovery process in an urban area affected by an earthquake. At the same time, this recovery index allows the recovery progress to be quantified based on indicators
Sufficient conditions for graphs to be maximally 4-restricted edge connected
No full textFor a subset S of edges in a connected graph G, the set S is a k-restricted edge cut if G − S is disconnected and every component of G − S has at least k vertices. The k-restricted edge connectivity of G, denoted by λk(G), is defined as the cardinality of a minimum k-restricted edge cut. A connected graph G is said to be λk-connected if G has a k-restricted edge cut. Let ξk(G) = min{|[X, ̅X ]| : |X| = k, G[X] is connected},
where ̅X = V (G)X. A graph G is said to be maximally k-restricted
edge connected if λk(G) = ξk(G). In this paper we show that if G is a λ₄-connected graph with λ₄(G) ≤ ξ₄(G) and the girth satisfies g(G) ≥ 8, and there do not exist six vertices u₁, u₂, u₃, v₁, v₂ and v₃ in G such that the distance d(ui, vj) ≥ 3, (1 ≤ i, j ≤ 3), then G is maximally 4-restricted
edge connected
Single P and As dopants in the Si(001) surface
No full textUsing first-principles density functional theory, we discuss doping of the Si(001) surface by a single substitutional phosphorus or arsenic atom. We show that there are two competing atomic structures for isolated Si–P and Si–As heterodimers, and that the donor electron is delocalized over the surface. We also show that the Si atom dangling bond of one of these heterodimer structures can be progressively charged by additional electrons. It is predicted that surface charge accumulation as a result of tip-induced band bending leads to structural and electronic changes of the Si–P and Si–As heterodimers which could be observed experimentally. Scanning tunneling microscopy (STM) measurements of the Si–P heterodimer on a n-type Si(001) surface reveal structural characteristics and a bias-voltage dependent appearance, consistent with these predictions. STM measurements for the As:Si(001) system are predicted to exhibit similar behavior to P:Si(001)
Cumulative incidence of admission to permanent residential aged care for Australian women - A competing risk analysis
No full textObjective: To provide a direct estimate of the risk of admission to permanent residential aged care among older women while accounting for death, according to housing type and other variables. Methods: A competing risk analysis from 8,867 Australian women born 1921¿26, using linked data from the Australian Longitudinal Study on Women's Health (ALSWH), Residential Aged Care (RAC), and the Australian National Death Index. Results: After accounting for deaths, around 35% of women will be admitted to RAC between ages 73 and 90. The conditional cumulative incidence of admission to RAC was 26.9% if living in a house, compared to 36.0% from an apartment, 43.6% within a retirement village, and 37.1% if living in a mobile home. Each one-year increase in age was associated with a relative 17% increased risk of RAC. Conclusions: Around one-third of women will enter RAC between age 73 and 90. Living in a house had the lowest risk of entering residential aged care over time. Implications for public health: These findings have important implications for planning for aged care services, including the role of housing in delaying admission to residential aged care, and the need for residential care by a high proportion of women towards the end of life