The Complicated Nature of Somatic mtDNA Mutations in Aging

Mitochondria are the main source of energy used to maintain cellular homeostasis. This aspect of mitochondrial biology underlies their putative role in age-associated tissue dysfunction. Proper functioning of the electron transport chain (ETC), which is partially encoded by the extra-nuclear mitochondrial genome (mtDNA), is key to maintaining this energy production. The acquisition of de novo somatic mutations that interrupt the function of the ETC have long been associated with aging and common diseases of the elderly. Yet, despite over 30 years of study, the exact role(s) mtDNA mutations play in driving aging and its associated pathologies remains under considerable debate. Furthermore, even fundamental aspects of age-related mtDNA mutagenesis, such as when mutations arise during aging, where and how often they occur across tissues, and the specific mechanisms that give rise to them, remain poorly understood. In this review, we address the current understanding of the somatic mtDNA mutations, with an emphasis of when, where, and how these mutations arise during aging. Additionally, we highlight current limitations in our knowledge and critically evaluate the controversies stemming from these limitations. Lastly, we highlight new and emerging technologies that offer potential ways forward in increasing our understanding of somatic mtDNA mutagenesis in the aging process.

From Automata to Multiautomata via Theory of Hypercompositional Structures

In this paper, we study two important problems related to quasi-multiautomata: the complicated nature of verification of the GMAC condition for systems of quasi-multiautomata, and the fact that the nature of quasi-multiautomata has deviated from the original nature of automata as seen by the theory of formal languages. For the former problem, we include several new conditions that simplify the procedure. For the latter problem, we close this gap by presenting a construction of quasi-multiautomata, which corresponds to deterministic automata of the theory of formal languages and is based on the operation of concatenation.

Can One Hear a Matrix? Recovering a Real Symmetric Matrix from Its Spectral Data

The spectrum of a real and symmetric $$N\times N$$ N × N matrix determines the matrix up to unitary equivalence. More spectral data is needed together with some sign indicators to remove the unitary ambiguities. In the first part of this work, we specify the spectral and sign information required for a unique reconstruction of general matrices. More specifically, the spectral information consists of the spectra of the N nested main minors of the original matrix of the sizes $$1,2,\ldots ,N$$ 1 , 2 , … , N . However, due to the complicated nature of the required sign data, improvements are needed in order to make the reconstruction procedure feasible. With this in mind, the second part is restricted to banded matrices where the amount of spectral data exceeds the number of the unknown matrix entries. It is shown that one can take advantage of this redundancy to guarantee unique reconstruction of generic matrices; in other words, this subset of matrices is open, dense and of full measure in the set of real, symmetric and banded matrices. It is shown that one can optimize the ratio between redundancy and genericity by using the freedom of choice of the spectral information input. We demonstrate our constructions in detail for pentadiagonal matrices.

Studying Sex to Understand Sexual Assault

This book review explores Sexual Citizens: A Landmark Study of Sex, Power, and Assault on Campus by Jennifer S. Hirsch and Shamus Khan, and describes the complicated nature of sexual experiences as an undergraduate.

LeukoSegmenter: A Double Encoder-decoder Based Network for Leukocyte Segmentation From Blood Smear Images

Segmentation of blood cells is a prerequisite step in automated morphological analysis of blood smear images, cell count determination and diagnosis of various diseases such as leukemia. It is extremely challenging due to different sizes, shapes, morphological characteristics and overlapping of blood cells. Due to its complicated nature, it is generally performed as a sequence of steps. However, sequential segmentation results in restricted accuracy due to cascading of errors that creep during each stage. On the contrary, pixel-wise segmentation of blood cells is a single step task and gives promising results. In this paper, we propose LeukoSegmenter, a double encoder-decoder for precise pixel-wise segmentation of leukocytes from blood smear images. It uses pre-trained ResNet18 based encoders and U-Net based decoders. Feature maps obtained from the first network are utilised as attention maps. These are used as input in conjunction with the original 3-channel image to obtain final mask from the second network. This mechanism allows the latter encoder-decoder pair to focus explicitly on leukocytes and ignore other blood cells and debris, thus improving the segmentation accuracy. Experiments on ALL-IDB1 dataset show that the proposed LeukoSegmenter achieves intersection-over-union score of 94.6827% and Dice score of 97.1987% which is superior than that of state-of-the-art methods.

[Un]blurring the Challenges Facing Post-Graduate Students in South African Universities: An Afrocentric Youth Perspective

South African senior academics do not accentuate the importance of the “publish or perish” mantra as required for young emerging scholars. This continued unfair and/or unjust practice is perpetuated further by a lack of attention to the problem, including less interest in research country-wide by some senior academics. It is in this context that—where this injustice is reported—it is often undermined and/or side-lined, or even critiqued. This paper is revisiting all of the various challenges faced by young emerging scholars in South African universities. Due to the complicated nature of the conduct of research in South African universities, the author did not pin-point any university by name, as this is the practical thorn that is evident country-wide and has been a systemic, strategic instigation to side-line emerging scholars in producing knowledge through various methods of gate-keeping. It is also delaying post-graduate students in the system for them to not see the importance of the continuation of post-graduate studies. Afrocentricity has been deployed as a theoretical lens, together with unstructured interviews and document reviews to collect data.

The Sikkim–Tibet Convention of 1890 and the Younghusband Mission of 1904

The controversy surrounding the Simla Conference of 1913–1914 and the legality of the McMahon line, which was produced by the Conference, has been at the centre of the boundary dispute between India and China. Amidst the diverging opinions amongst scholars and political commentators, the main issue rest on the unresolved question of Tibet’s political status. Was Lhasa authorised to sign treaties for Tibet? Was China the sovereign over Tibet? The answers to such questions are murky and complicated, made more so by the politics and conflicts in the post colonial period. This study attempts to highlight the complicated nature of political authority in Tibet through a study of British policy in Tibet towards the end of 19th and early 20th centuries. The signing of the 1890 Convention with China and the 1904 Convention with Tibet represents two extremes in British foreign policy which attest to the confounding situation presented before the British and the diverging opinions within the British official circles. The period between these two conventions provides a glimpse of the historical background in which the relations between British India, China and Tibet developed subsequently.

Multifaceted Asylum Triangle: Does Fragmentation of the Right to Asylum and the Non-Refoulement Rule Deters the Functioning of Equitable and Predictable Burden- and Responsibility-Sharing Mechanism on Refugees?

The global refugee protection system is founded on two core values, assuring a safe and dignified life away from violent regimes and conflicts: the right to asylum and the non-refoulement rule. While there are no internationally agreed definitions for these concepts, their fragmentation affects the equitable and predictable burden- and responsibility-sharing, and subsequently, successful international cooperation in refugee matters. By analysing the right to asylum in legal theory and examining its application in the jurisprudence of international human rights monitoring bodies, this article seeks to explore the complexity of heterogeneous approaches with regard to refugees. Furthermore, the impediments to the functioning of the current refugee protection regime is identified by analysing the complicated nature of its umbrella maxim - the non-refoulement rule. The article examines how the lack of clarity on the contents of the right to asylum and the non-refoulement rule causes different, sometimes contradictory, approaches regarding the corresponding international obligations of states. It further explores how the diversified understanding of these foundational principles makes it difficult to identify common protection needs and the responsibilities of states with regard to international cooperation and burden- and responsibility-sharing on refugee matters. Eventually, the fragmentation of these core values threatens their unequivocal application and results in failing refugee protection regimes. Consequently, this article argues that a common understanding on the right to asylum and non-refoulement rule represents a condicio sine qua non for securing equitable and predictable burden- and responsibility-sharing mechanism in refugee matters.

Observing silent, smooth and striated space: The case of Indian national curriculum policy 2009

The paper employs the assemblage approach to unfold India’s 2009 education policy, the National Curriculum Framework, in order to uncover its multiple international, national or other links. In doing so, a deconstruction approach (as strategy, not as rationale) is applied, in order to uncover the policy text and what is identified as a construction and reconstruction of meaning. The contested notion of student-centred learning and its perspective is proposed as a solution to deal with the professionalism problem of Indian teachers and the criteria to develop teachers’ professional skills are closely analysed. As a result, it is not only student-centred learning that is apprised to be part of the National Curriculum Framework, but also its multiple versions, linked to local and global policy studies. In turn, this highlights the complicated nature of the policy. The multifaceted and manifold versions of student-centred learning are further unfolded through the assemblage rationale. Silent spaces (e.g. teachers’ voices, teaching evaluation methods, etc.) are observed in the policy text to accommodate the emergence of student-centred learning.

Trending approaches on demulsification of crude oil in the petroleum industry

The complicated nature of crude oil emulsions is part of the major setbacks associated with the postulation of methods for phase separation and demulsification in the oil industry. Despite the increasing efforts in generating efficient and dependable demulsification methods, the majority of emulsions cannot be shattered in reduced times. This review examines the trending techniques of crude oil demulsification in the petroleum industry. Several approaches have been examined to discover the best method of demulsification. Hence, this reports reviewed the past studies on the emulsion, formation of oil emulsions, methods of demulsification, characteristics of demulsifier, mechanism of demulsification, kinetics in demulsification, operating parameters influencing the demulsification processes, the structure of demulsifier, and formulations that are involved in the demulsification. The formulations of crude oil demulsification have been investigated to unveil adequate demulsifiers for crude oil. Therefore, demulsification approaches have several applications due to wider varieties of crude oil, separation equipment, brines, chemical demulsifiers, the method in which demulsifiers is been formulated, and product specifications.