The principles of helium exploration

Commercial helium systems have been found to date as a serendipitous by-product of petroleum exploration. There are nevertheless significant differences in the source and migration properties of helium compared with petroleum. An understanding of these differences enables prospects for helium gas accumulations to be identified in regions where petroleum exploration would not be tenable. Here we show how the basic petroleum exploration playbook (source, primary migration from the source rock, secondary longer distance migration, trapping) can be modified to identify helium plays. Plays are the areas occupied by a prospective reservoir and overlying seal associated with a mature helium source. This is the first step in identifying the detail of helium prospects (discrete pools of trapped helium). We show how these principles, adapted for helium, can be applied using the Rukwa Basin in the Tanzanian section of the East African Rift as a case study. Thermal hiatus caused by rifting of the continental basement has resulted in a surface expression of deep crustal gas release in the form of high-nitrogen gas seeps containing up to 10% 4He. We calculate the total likely regional source rock helium generative capacity, identify the role of the Rungwe volcanic province in releasing the accumulated crustal helium, and show the spatial control of helium concentration dilution by the associated volcanic CO2. Nitrogen, both dissolved and as a free gas phase, plays a key role in the primary and secondary migration of crustal helium and its accumulation into what might become a commercially viable gas pool. This too is examined. We identify and discuss evidence that structures and seals suitable for trapping hydrocarbon and CO2 gases will likely also be efficient for helium accumulation on the timescale of the Rukwa basin activity.The Rukwa Basin prospective recoverable P50 resources of helium have been independently estimated to be about 138 billion standard cubic feet (2.78 x 109 m3 at STP). If this volume is confirmed it would represent about 25% of the current global helium reserve. Two exploration wells Tai 1 and Tai 2 completed by August 2021 have proved the presence of seal and reservoir horizons with the reservoirs containing significant helium shows.This article is part of the Energy Geoscience Series available at https://www.lyellcollection.org/cc/energy-geoscience-series

Ethical and Bioethical Aspects in the Use of Stem Cells in Chronic Spinal Cord Injuries

One of the fundamental dogmas maintained in neuroscience until the last century held that regeneration of the nervous system cannot occur in stages of adult life. However, it has been shown in several species during the postnatal stage and throughout life, that new neurons continue to be generated in some places in the human body. Objectives: The research was: to evaluate ethical and bioethical aspects in patients who were treated with an autologous stem cell implant in chronic spinal cord injuries. Method. An analysis is made of the ethical aspects that accompany the implantation of autologous stem cells in chronic spinal cord injuries. The results are evaluated at the "Enrique Cabrera" Surgical Clinical Teaching Hospital. Results: Ethical dilemmas are expressed and that have, among their relevant principles, the inviolability of human life. In higher animals, stem cells according to their evolutionary state can be embryonic and somatic or adult. Currently there is an extraordinary controversy about which stem cells to use from embryonic or adult ones, a debate in which both scientific, ethical, religious, social and political aspects have been included. One aspect of the scientific debate is related to the generative capacity of tumors by embryonic cells. From the ethical point of view, it has been argued that the use of human embryonic stem cells implies the destruction of embryos and it has been considered that life begins at the same moment of the union of the sperm with the ovum and that this would be equivalent to the destruction of a human life which would not be justifiable. Others do not agree with these criteria and argue that their use to save lives through research or therapy would be justified. Conclusions The physical disability produced by a chronic spinal cord injury raises an ethical dilemma about the use of stem cells, anticipating that the main controversy about this action has to do fundamentally with the way in which they are obtained.

Variation in mild context-sensitivity

Aravind Joshi famously hypothesized that natural language syntax was characterized (in part) by mildly context-sensitive generative power. Subsequent work in mathematical linguistics over the past three decades has revealed surprising convergences among a wide variety of grammatical formalisms, all of which can be said to be mildly context-sensitive. But this convergence is not absolute. Not all mildly context-sensitive formalisms can generate exactly the same stringsets (i.e. they are not all weakly equivalent), and even when two formalisms can both generate a certain stringset, there might be differences in the structural descriptions they use to do so. It has generally been difficult to find cases where such differences in structural descriptions can be pinpointed in a way that allows linguistic considerations to be brought to bear on choices between formalisms, but in this paper we present one such case. The empirical pattern of interest involves wh-movement dependencies in languages that do not enforce the wh-island constraint. This pattern draws attention to two related dimensions of variation among formalisms: whether structures grow monotonically from one end to another, and whether structure-building operations are conditioned by only a finite amount of derivational state. From this perspective, we show that one class of formalisms generates the crucial empirical pattern using structures that align with mainstream syntactic analysis, and another class can only generate that same string pattern in a linguistically unnatural way. This is particularly interesting given that (i) the structurally-inadequate formalisms are strictly more powerful than the structurally-adequate ones from the perspective of weak generative capacity, and (ii) the formalism based on derivational operations that appear on the surface to align most closely with the mechanisms adopted in contemporary work in syntactic theory (merge and move) are the formalisms that fail to align with the analyses proposed in that work when the phenomenon is considered in full generality.

The generative capacity of probabilistic protein sequence models

Potts models and variational autoencoders (VAEs) have recently gained popularity as generative protein sequence models (GPSMs) to explore fitness landscapes and predict mutation effects. Despite encouraging results, current model evaluation metrics leave unclear whether GPSMs faithfully reproduce the complex multi-residue mutational patterns observed in natural sequences due to epistasis. Here, we develop a set of sequence statistics to assess the “generative capacity” of three current GPSMs: the pairwise Potts Hamiltonian, the VAE, and the site-independent model. We show that the Potts model’s generative capacity is largest, as the higher-order mutational statistics generated by the model agree with those observed for natural sequences, while the VAE’s lies between the Potts and site-independent models. Importantly, our work provides a new framework for evaluating and interpreting GPSM accuracy which emphasizes the role of higher-order covariation and epistasis, with broader implications for probabilistic sequence models in general.

Between Subjectivity and Flourishing: Creativity and Game Design as Existential Meaning

This article explores how the process of designing videogames may be meaningful–that is, accomplish a larger existential fulfilment or purpose. We use a reflective methodology which triangulates the creative practice of making a videogame with reflections both during and post-practice against philosophical ideas of meaningfulness. Two ideas of meaningfulness emerged. The first is the generative capacity of subjectivity, where meaningfulness is anchored to our investment as creators, as well as in the intertwining of personal histories, experiences and memories between reflection and action. The second is the flourishing of the self in terms of inner growth and self-discovery out of journeying inherent in the game design process. The significance of our enquiry is three-fold: to more holistically understand videogames as being meaningful, to present a reflective methodology to facilitate such understanding, and to more broadly consider videogames as an instantiation of how media is itself existential.

House as Autobiography: An Architectural (Mis)Translation of My Kitchen

<p><b>This research unravels and reconstructs the all-enveloping, surreal-slowness of my kitchen during Level-4 lockdown; through the intimate familiarity of the line, and the tactility of paper. In a time and place defined by the assimilation of our public and private lives, physical boundaries that ordinarily served to separate and structure, were dissolved. Within this physically smaller world, the kitchen felt relatively larger. </b></p> <p>Architecture and the kitchen (and equally, food and cooking) have long since existed within one another, both physically (in space) and etymologically. Isodore de Seville postulated that architecture first emerged in the dining hall, where the first building was made for eating. Equally, cooking and eating rely on a more-or-less solid and spatial framework.</p> <p>Within the “pseudo-fastness” of the architectural industry, drawing is a comparatively slow and contemplative practice, cultivating an attention to detail, and embodying the capacity to enhance social and historic values. Equally, the generative capacity of drawing makes it uniquely capable of creating something new, from something else. </p> <p>Just as lockdown was a recluse from the pace of everyday life, drawing is a recluse from the pace of normative architectural practice. The outcome of the research is a series of autobiographic houses, equally symptoms of the introspective experience of lockdown, and the introspective practice of drawing. </p> <p>By exploiting the subtle parallels that transcend architectural practice, language, and the kitchen (and cooking); this research makes a sensitive proposition for a design practice deeply implicated by the composition of temporal and spatial conditions from which it is conceived.</p>

House as Autobiography: An Architectural Mis(Translation) of My Kitchen

<p><b>This research unravels and reconstructs the all-enveloping, surreal-slowness of my kitchen during Level-4 lockdown; through the intimate familiarity of the line, and the tactility of paper. In a time and place defined by the assimilation of our public and private lives, physical boundaries that ordinarily served to separate and structure, were dissolved. Within this physically smaller world, the kitchen felt relatively larger. </b></p> <p>Architecture and the kitchen (and equally, food and cooking) have long since existed within one another, both physically (in space) and etymologically. Isodore de Seville postulated that architecture first emerged in the dining hall, where the first building was made for eating. Equally, cooking and eating rely on a more-or-less solid and spatial framework.</p> <p>Within the “pseudo-fastness” of the architectural industry, drawing is a comparatively slow and contemplative practice, cultivating an attention to detail, and embodying the capacity to enhance social and historic values. Equally, the generative capacity of drawing makes it uniquely capable of creating something new, from something else. </p> <p>Just as lockdown was a recluse from the pace of everyday life, drawing is a recluse from the pace of normative architectural practice. The outcome of the research is a series of autobiographic houses, equally symptoms of the introspective experience of lockdown, and the introspective practice of drawing. </p> <p>By exploiting the subtle parallels that transcend architectural practice, language, and the kitchen (and cooking); this research makes a sensitive proposition for a design practice deeply implicated by the composition of temporal and spatial conditions from which it is conceived.</p>

House as Autobiography: An Architectural Mis(Translation) of My Kitchen

<p><b>This research unravels and reconstructs the all-enveloping, surreal-slowness of my kitchen during Level-4 lockdown; through the intimate familiarity of the line, and the tactility of paper. In a time and place defined by the assimilation of our public and private lives, physical boundaries that ordinarily served to separate and structure, were dissolved. Within this physically smaller world, the kitchen felt relatively larger. </b></p> <p>Architecture and the kitchen (and equally, food and cooking) have long since existed within one another, both physically (in space) and etymologically. Isodore de Seville postulated that architecture first emerged in the dining hall, where the first building was made for eating. Equally, cooking and eating rely on a more-or-less solid and spatial framework.</p> <p>Within the “pseudo-fastness” of the architectural industry, drawing is a comparatively slow and contemplative practice, cultivating an attention to detail, and embodying the capacity to enhance social and historic values. Equally, the generative capacity of drawing makes it uniquely capable of creating something new, from something else. </p> <p>Just as lockdown was a recluse from the pace of everyday life, drawing is a recluse from the pace of normative architectural practice. The outcome of the research is a series of autobiographic houses, equally symptoms of the introspective experience of lockdown, and the introspective practice of drawing. </p> <p>By exploiting the subtle parallels that transcend architectural practice, language, and the kitchen (and cooking); this research makes a sensitive proposition for a design practice deeply implicated by the composition of temporal and spatial conditions from which it is conceived.</p>

On the generative capacity of matrix insertion-deletion systems of small sum-norm

A matrix insertion-deletion system (or matrix ins-del system) is described by a set of insertion-deletion rules presented in matrix form, which demands all rules of a matrix to be applied in the given order. These systems were introduced to model very simplistic fragments of sequential programs based on insertion and deletion as elementary operations as can be found in biocomputing. We are investigating such systems with limited resources as formalized in descriptional complexity. A traditional descriptional complexity measure of such a matrix ins-del system is its size $$s=(k;n,i',i'';m,j',j'')$$ s = ( k ; n , i ′ , i ′ ′ ; m , j ′ , j ′ ′ ) , where the parameters from left to right represent the maximal matrix length, maximal insertion string length, maximal length of left contexts in insertion rules, maximal length of right contexts in insertion rules; the last three are deletion counterparts of the previous three parameters. We call the sum $$n+i'+i''+m+j'+j''$$ n + i ′ + i ′ ′ + m + j ′ + j ′ ′ the sum-norm of s. We show that matrix ins-del systems of sum-norm 4 and sizes (3; 1, 0, 0; 1, 2, 0), (3; 1, 0, 0; 1, 0, 2), (2; 1, 2, 0; 1, 0, 0), (2; 1, 0, 2; 1, 0, 0), and (2; 1, 1, 1; 1, 0, 0) describe the recursively enumerable languages. Moreover, matrix ins-del systems of sizes (3; 1, 1, 0; 1, 0, 0), (3; 1, 0, 1; 1, 0, 0), (2; 2, 1, 0; 1, 0, 0) and (2; 2, 0, 1; 1, 0, 0) can describe at least the regular closure of the linear languages. In fact, we show that if a matrix ins-del system of size s can describe the class of linear languages $$\mathrm {LIN}$$ LIN , then without any additional resources, matrix ins-del systems of size s also describe the regular closure of $$\mathrm {LIN}$$ LIN . Finally, we prove that matrix ins-del systems of sizes (2; 1, 1, 0; 1, 1, 0) and (2; 1, 0, 1; 1, 0, 1) can describe at least the regular languages.