Influential Article Review -Investment Choices Under Unpredictability on LNG-Powered Vessels

This paper examines investment. We present insights from a highly influential paper. Here are the highlights from this paper: The shipping industry is investigating alternative fuels for ships, in order to comply with stricter emission requirements implemented by International Maritime Organization (IMO). Liquefied Natural Gas (LNG) is a promising alternative since it could reduce emissions substantially and offer potential fuel cost savings. But the investment in LNG fuelled vessels is currently facing a high degree of uncertainty, such as the differential between the prices of LNG and conventional maritime fuels, the availability of LNG and the reliability of its supply chain. This paper makes an attempt to study the possibility of investing in LNG powered vessels under uncertainty. A deferral option model is proposed to quantify the value of flexibility for deferral based on multi-variables following specified stochastic processes. By exploiting the stochastic processes, it is possible to determine the value of deferral by solving a dynamic program using a least squares Monte Carlo simulation. The model is tested on an investment of a new chemical vessel with 19,000 dwt powered by LNG. Empirical analysis may suggest different investment strategies based on the probabilities of exercising an option and related option values each year. It indicates further that the attractiveness of LNG as ship fuel is dominated by a couple of parameters: difference of ship prices between a LNG powered vessel and a reference one, the price differential between LNG and conventional fuel prices, the share of the sailing time inside Emission Control Areas (ECAs), and the supply cost of LNG. For our overseas readers, we then present the insights from this paper in Spanish, French, Portuguese, and German

Synthetic lethal analysis of Caenorhabditis elegans posterior embryonic patterning genes identifies conserved genetic interactions

Phenotypic robustness is evidenced when single-gene mutations do not result in an obvious phenotype. It has been suggested that such phenotypic stability results from 'buffering' activities of homologous genes as well as non-homologous genes acting in parallel pathways. One approach to characterizing mechanisms of phenotypic robustness is to identify genetic interactions, specifically, double mutants where buffering is compromised. To identify interactions among genes implicated in posterior patterning of the Caenorhabditis elegans embryo, we measured synthetic lethality following RNA interference of 22 genes in 15 mutant strains. A pair of homologous T-box transcription factors (tbx-8 and tbx-9) is found to interact in both C. elegans and C. briggsae, indicating that their compensatory function is conserved. Furthermore, a muscle module is defined by transitive interactions between the MyoD homolog hlh-1, another basic helix-loop-helix transcription factor, hnd-1, and the MADS-box transcription factor unc-120. Genetic interactions within a homologous set of genes involved in vertebrate myogenesis indicate broad conservation of the muscle module and suggest that other genetic modules identified in C. elegans will be conserved

Détresse psychologique chez les personnes atteintes du VIH à Montréal

Le présent article décrit les préoccupations psychologiques reliées au VIH dans un échantillon montréalais de 128 personnes atteintes du virus, qui ont participé à une enquête nationale plus large sur les besoins et les services en santé mentale en rapport avec cette infection au Canada. Nous avons examiné les problèmes psychologiques causés par le VIH à Montréal, en comparaison d'autres villes du Canada, et dans divers sous-groupes définis selon le sexe, l'âge, le diagnostic et le facteur de risque. Les résultats montrent que même si l'infection au VIH a de fortes et profondes incidences sur la santé mentale, il existe des différences dans les genres de préoccupations et de problèmes qui affligent des groupes particuliers de répondants montréalais. L'incertitude de l'avenir et l'incapacité de réaliser ses buts dans la vie, ainsi que des sentiments d'impuissance et de peur face aux conséquences neurologiques virtuelles du VIH, étaient des sources majeures de détresse psychologique. Les sentiments de dépression, d'anxiété et de colère, de même que les inquiétudes soulevées par une détérioration physique croissante, la douleur, le danger d'infecter autrui, la confidentialité et la situation financière, étaient des sujets d'angoisse prédominants parmi les sous-groupes étudiés. Les différences entre les répondants en termes de sources de revenu, d'âge et de sexe et, dans une moindre mesure, de diagnostic et de facteur de risque, étaient associées à des niveaux variables de détresse psychologique. Bien que les répondants de Montréal (et de Vancouver) étaient moins angoissés que ceux de Toronto et de Halifax, cette divergence semblait tenir principalement à des différences d'âge et de revenu. Les données de l'enquête pourront servir aux décideurs et aux planificateurs du domaine de la santé à mettre au point les services nécessaires pour répondre aux besoins psychologiques des adultes atteints du VIH.This paper describes the HIV-related mental health concerns of a sample of 128 persons with HIV infection in Montréal who participated in a larger national survey of HIV-related mental health needs and services in Canada. We examined mental health distress in persons with HIV infection in Montréal compared to other cities in Canada, and in subgroups of HIV-infected Montrealers defined on the basis of sex, age, diagnosis, and risk factor status. Results demonstrate that although HIV infection has a strong and far reaching impact on mental health, there are differences in the types of concerns and issues that are distressing to specific groups of Montréal respondents. Uncertainty about the future and not being able to realize life goals, as well as feelings of helplessness and fears about potential adverse neurological consequences of HIV disease, were major sources of psychological distress. Feelings of depression, anxiety, and anger, as well as concerns about increasing physical disability, pain, infecting others, confidentiality, and finances were predominant concerns among specific subgroups. Differences between respondents in terms of source of income, age, and sex, and to a lesser extent diagnosis and risk factor status, were associated with varying levels of mental health distress. Although respondents in Montréal (and Vancouver) were more distressed than respondents in Toronto and Halifax, these differences appear to be due primarily to differences in age and source of income. Findings from this study will be useful to policy makers and health planners in developing services to meet the mental health needs of HIV infected adults

Sighting the apu: A GIS Analysis of Wari Imperialism and the Worship of Mountain Peaks

Abstract: In the Andes, prominent mountains are revered as earthly spirits that protect, but may also punish, their human constituents. These apu were often linked to distant ancestors and are considered the most important local deities. During the phase of the earliest highland Andean expansive states (ad 600-1000), the Wari and Tiwanaku utilized mountain worship as a means of establishing hegemony over local peoples who considered these mountains as places of ancestral origins. By usurping the apu, or including them in the pantheon of imperial deities, the expansive state effectively held these sacred places hostage and incorporated local belief systems into an imperial ideology. Recent research has yielded new clues to the worship of mountain peaks, including the usurpation of a unique geological mesa formation at Cerro Baúl as the basis for the Wari colonization of its southern frontier. Furthermore, research on the mountain summit has revealed architectural complexes oriented to, and presumably dedicated for, rites of veneration to the higher snowcapped volcanic peaks visible from this mountain summit

Conceptualización y análisis psicológico del error humano en la conducción de vehículos a partir de los desarrollos recientes del modelo de habilidades, reglas y conocimientos

The Skills, Rules and Knowledge model (Rasmussen, 1987, 1986, 1983) is a theoretical-conceptual model that falls within the framework of information processing of cognitive psychology, and constitutes one of the principal models within which the performance of tasks that form part of complex activities such as driving motor vehicles have been researched both theoretically and empirically. Within this theoretical framework, driving behavior is explained in tems of cognitive information processing: the notions of cognitive control in the perfonnance of tasks and the distinction between automatic and controlled processing constitute the basis of this explanation. This explanation also includes the functioning of basic psychological factors and processes that underlie driving behavior: attention, complex leaming (perceptional, attentional, motor), experience, memory, perceptive-motorprocesses, etc. During the 90's along these same lines and within this theoretic framework, errors in human behavior that precede trafic accidents were studied. In this way, the theoretical-conceptual basis of this model -and the perspective of cogrtitive information processing in general- has guided the greater part of the theoretical and empirical research that is conducted in order to prevent human errors and accidents within the field of Trafic and Road Safety Psychology today. Based on recent developments related to the Skills, Rules and Knowledge model (Reason, 1994, 1990, 1987), a theory of considerable complexity has been elaborated which provides un explanation for the occurrence of human errors in driving (especially unintentional errors) and, to a large extent, sheds light on the functioning of some basic psychological factors and processes that underlie such errors. The objective of this paper is to study these psychological factors and processes, as well as to provide a conceptual analysis and an analysis of the categories of human error in driving that are included within this theoretical framework.El modelo de habilidades, reglas y conocimientos (Rasmussen, 1987, 1986, 1983) es un modelo teórico-conceptual que se encuadra en el marco psicológico cognitivo del procesamiento de la información, y constituye uno de los principales modelos desde los cuales se ha investigado teórica y empíricamente la ejecución de las tareas que forman parte de actividades complejas como es la conducción de vehículos automóviles. Desde este marco teórico, el comportamiento humuno en la conducción se explica en términos cognitivos del procesamiento de la información: las nociones sobre control cognitivo en la ejecución de tareas y la distinción entre procesamiento automático y controlado constituyen la base de dicha explicación: ésta, además, se articula en tomo al funcionamiento de los factores procesos psicológicos básicos que subyacen al comportamiento humano en la conducción: atención, aprendizajes complejos (perceptivo, atencional y motor), experiencia, memoria, procesos perceptiva-motores, etc. De la misma manera, y a partir de planteamientos similares, en los aiios 90 se ha investigado desde este marco teórico el comportamiento humano erróneo que precede a los accidentes de tráfico, de manera que los planteamientos teórico-conceptuales de este modelo -y, en general, de la perspectiva cognitiva del procesamiento de la información- han guiado buena parte de la investigación teórica y empírica que se lleva a cabo actualmente para la prevención de los errores humanos y de la accidentalidad desde el ámbito de la Psicología del Tráfico y Seguridad Vial. Asi, desde los desarrollos recientes del modelo de habilidades, reglas y conocimientos (Reason, 1994, 1990, 1987) se ha llevado a cabo un planteamiento con un grado de elaboración considerable que permite explicar la ocurrencia de los errores humanos (no intencionales) en la conducción y esclarecer en buena medida el funcionamiento de algunos de los factores y procesos psicológicos búsicos que están detrás de tales errores. El estudio de dichos factores y procesos psicológicos, así como el análisis conceptual y de las categorizaciones del error humano en la conducción que se plantean desde este marco teórico, constituyen los objetivos básicos del presente trabajo

The homeodomain protein PAL-1 specifies a lineage-specific regulatory network in the C. elegans embryo

Maternal and zygotic activities of the homeodomain protein PAL-1 specify the identity and maintain the development of the multipotent C blastomere lineage in the C. elegans embryo. To identify PAL-1 regulatory target genes, we used microarrays to compare transcript abundance in wild-type embryos with mutant embryos lacking a C blastomere and to mutant embryos with extra C blastomeres. pal-1-dependent C-lineage expression was verified for select candidate target genes by reporter gene analysis, though many of the target genes are expressed in additional lineages as well. The set of validated target genes includes 12 transcription factors, an uncharacterized wingless ligand and five uncharacterized genes. Phenotypic analysis demonstrates that the identified PAL-1 target genes affect specification, differentiation and morphogenesis of C-lineage cells. In particular, we show that cell fate-specific genes (or tissue identity genes) and a posterior HOX gene are activated in lineage-specific fashion. Transcription of targets is initiated in four temporal phases, which together with their spatial expression patterns leads to a model of the regulatory network specified by PAL-1

A timeseries analysis of the fracture callus extracellular matrix proteome during bone fracture healing.

While most bones fully self-heal, certain diseases require bone allograft to assist with fracture healing. Bone allografts offer promise as treatments for such fractures due to their osteogenic properties. However, current bone allografts made of decellularized bone extracellular matrix (ECM) have high failure rates, and thus grafts which improve fracture healing outcomes are needed. Understanding specific changes to the ECM proteome during normal fracture healing would enable the identification of key proteins that could be used enhance osteogenicity of bone allograft. Here, we performed a timeseries analysis of the fracture callus in mice to investigate proteomic and mineralization changes to the ECM at key stages of fracture healing. We found that changes to the ECM proteome largely coincide with the distinct phases of fracture healing. Basement membrane proteins (AGRN, COL4, LAMA), cartilage proteins (COL2A1, ACAN), and collagen crosslinking enzymes (LOXL, PLOD, ITIH) were initially upregulated, followed by bone specific proteoglycans and collagens (IBSP, COL1A1). Various tissue proteases (MMP2, 9, 13, 14; CTSK, CTSG, ELANE) were expressed at different levels throughout fracture healing. These changes coordinated with mineralization of the fracture callus, which increased steeply during the initial stages of healing. Interestingly the later timepoint was characterized by a response to wound healing and high expression of clotting factors (F2, 7, 9, 10). We identified ELANE and ITIH2 as tissue remodeling enzymes having no prior known involvement with fracture healing. This data can be further mined to identify regenerative proteins for enhanced bone graft design