scholarly journals Taphonomy of marine vertebrates of the Pisco Formation (Miocene, Peru): Insights into the origin of an outstanding Fossil-Lagerstätte

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254395
Author(s):  
Giulia Bosio ◽  
Alberto Collareta ◽  
Claudio Di Celma ◽  
Olivier Lambert ◽  
Felix G. Marx ◽  
...  
Keyword(s):  
Comprehensive Overview ◽  
Exceptional Preservation ◽  
The Past ◽  
Bite Marks ◽  
Shark Teeth ◽  
Pisco Formation ◽  
Carbonate Concretions ◽  
Anoxic Events ◽  
Low Levels ◽  
Taphonomic Processes

The Miocene Pisco Formation, broadly exposed in the Ica Desert of southern Peru, is among the most outstanding Cenozoic marine Fossil-Lagerstätten worldwide. It is renowned for its exceptional preservation and abundance of vertebrate fossils, including a rich assemblage of whales and dolphins (Cetacea). Here, we integrate taphonomic data on 890 marine vertebrate fossils, gathered through 16 different localities. Our observations range from the taxonomic distribution, articulation, completeness, disposition and orientation of skeletons, to the presence of bite marks, associations with shark teeth and macro-invertebrates, bone and soft tissue preservation, and the formation of attendant carbonate concretions and sedimentary structures. We propose that the exceptional preservation characterising many Pisco vertebrates, as well as their exceptionally high abundance, cannot be ascribed to a single cause like high sedimentation rates (as proposed in the past), but rather to the interplay of several favourable factors including: (i) low levels of dissolved oxygen at the seafloor (with the intervention of seasonal anoxic events); (ii) the early onset of mineralisation processes like apatite dissolution/recrystallisation and carbonate mineral precipitation; (iii) rapid burial of carcasses in a soupy substrate and/or a novel mechanism involving scour-induced self-burial; and (iv) original biological richness. Collectively, our observations provide a comprehensive overview of the taphonomic processes that shaped one of South America’s most important fossil deposits, and suggest a model for the formation of other marine vertebrate Fossil-Lagerstätten.

scholarly journals The emergence of coercive federal Australian labour law, 1901–2020

2021 ◽  
pp. 002218562110039
Author(s):  
Eugene Schofield-Georgeson
Keyword(s):  
Industrial Relations ◽  
High Volume ◽  
Union Power ◽  
Labour Law ◽  
Industrial Environment ◽  
The Past ◽  
Low Levels ◽  
Labour Legislation ◽  
Employment Legislation

Over the past two decades, industrial relations scholarship has observed a trend towards an increasingly punitive industrial environment along with the ‘re-regulation’ of labour law. Absent from much of this literature, however, has been an empirical and historical measurement or comparison of the scale and quality of this systemic change. By surveying coercive and penal federal industrial legislation over the period 1901–2020, this study shows empirically that over the last 40 years, there has been a steep increase in the amount of coercive federal labour legislation in Australia. It further measures and compares the volume of coercive labour legislation enacted specifically against ‘labour’ and ‘capital’ or both throughout the same period (1901–2020). Analysis reveals a correlation between a high volume of coercive labour legislation with low levels of trade union power and organisation. Argued here is that coercive labour legislation has been crucial to transitioning from a liberal conciliation and arbitration model of Australian industrial relations towards a neoliberal framework of employment legislation. In the former, regulation was more collective, informal and egalitarian (embodied by the sociological concept of ‘associative democracy’). Under a neoliberal framework, regulation is now more individualised, technical, punitive and rarely enforced, resulting in less equal material outcomes.

scholarly journals Flying Free: A Research Overview of Deep Learning in Drone Navigation Autonomy

Drones ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 52
Author(s):  
Thomas Lee ◽  
Susan Mckeever ◽  
Jane Courtney
Keyword(s):  
Deep Learning ◽  
Research Work ◽  
Learning Approaches ◽  
Clear Definition ◽  
Top Down ◽  
Research Activity ◽  
Comprehensive Overview ◽  
The Past ◽  
Computer Vision Applications ◽  
Definition Of

With the rise of Deep Learning approaches in computer vision applications, significant strides have been made towards vehicular autonomy. Research activity in autonomous drone navigation has increased rapidly in the past five years, and drones are moving fast towards the ultimate goal of near-complete autonomy. However, while much work in the area focuses on specific tasks in drone navigation, the contribution to the overall goal of autonomy is often not assessed, and a comprehensive overview is needed. In this work, a taxonomy of drone navigation autonomy is established by mapping the definitions of vehicular autonomy levels, as defined by the Society of Automotive Engineers, to specific drone tasks in order to create a clear definition of autonomy when applied to drones. A top–down examination of research work in the area is conducted, focusing on drone navigation tasks, in order to understand the extent of research activity in each area. Autonomy levels are cross-checked against the drone navigation tasks addressed in each work to provide a framework for understanding the trajectory of current research. This work serves as a guide to research in drone autonomy with a particular focus on Deep Learning-based solutions, indicating key works and areas of opportunity for development of this area in the future.

Hierarchical Reinforcement Learning

2021 ◽  
Vol 54 (5) ◽  
pp. 1-35
Author(s):  
Shubham Pateria ◽  
Budhitama Subagdja ◽  
Ah-hwee Tan ◽  
Chai Quek
Keyword(s):  
Reinforcement Learning ◽  
Future Research ◽  
Comprehensive Overview ◽  
Open Problems ◽  
Practical Applications ◽  
Hierarchical Reinforcement Learning ◽  
The Past ◽  
Agent Learning ◽  
Multi Agent ◽  
Supplementary Material

Hierarchical Reinforcement Learning (HRL) enables autonomous decomposition of challenging long-horizon decision-making tasks into simpler subtasks. During the past years, the landscape of HRL research has grown profoundly, resulting in copious approaches. A comprehensive overview of this vast landscape is necessary to study HRL in an organized manner. We provide a survey of the diverse HRL approaches concerning the challenges of learning hierarchical policies, subtask discovery, transfer learning, and multi-agent learning using HRL. The survey is presented according to a novel taxonomy of the approaches. Based on the survey, a set of important open problems is proposed to motivate the future research in HRL. Furthermore, we outline a few suitable task domains for evaluating the HRL approaches and a few interesting examples of the practical applications of HRL in the Supplementary Material.

scholarly journals Glioblastoma Multiforme—A Look at the Past and a Glance at the Future

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1053
Author(s):  
Jasmine L. King ◽  
Soumya Rahima Benhabbour
Keyword(s):  
Glioblastoma Multiforme ◽  
Immune Surveillance ◽  
Standard Of Care ◽  
Current Standard ◽  
Comprehensive Overview ◽  
Therapeutic Delivery ◽  
The Past ◽  
Adults And Children ◽  
The Central Nervous System ◽  
Delivery Strategies

Gliomas are the most common type of brain tumor that occur in adults and children. Glioblastoma multiforme (GBM) is the most common, aggressive form of brain cancer in adults and is universally fatal. The current standard-of-care options for GBM include surgical resection, radiotherapy, and concomitant and/or adjuvant chemotherapy. One of the major challenges that impedes success of chemotherapy is the presence of the blood–brain barrier (BBB). Because of the tightly regulated BBB, immune surveillance in the central nervous system (CNS) is poor, contributing to unregulated glioma cell growth. This review gives a comprehensive overview of the latest advances in treatment of GBM with emphasis on the significant advances in immunotherapy and novel therapeutic delivery strategies to enhance treatment for GBM.

Breeding and Mating Systems of Australian Proteaceae

1998 ◽  
Vol 46 (4) ◽  
pp. 421 ◽  
Author(s):  
Ross L. Goldingay ◽  
Susan M. Carthew
Keyword(s):  
Fruit Development ◽  
Mating Systems ◽  
Pollen Deposition ◽  
Genetic Studies ◽  
The Past ◽  
Wide Range ◽  
The Family ◽  
Self Compatibility ◽  
Low Levels ◽  
Key Events

There has been a significant increase in the number of studies investigating plant breeding and mating systems over the past 10 years. The family Proteaceae, in particular, has dominated such research conducted in Australia. Thus it is now timely to present a critical review of the breeding and mating systems of the Australian Proteaceae. It is hoped that this will stimulate further research. The review covers key events between pollen deposition on stigmas through to fruit set. The genus Banksia, although not the most diverse of the family, has received a disproportionate amount of attention. It has featured in nine published studies of self-compatibility compared to 13 studies spanning the other 45 genera and has featured in eight genetic studies of the mating system compared to just two on other genera. Few studies have assessed the timing of stigma receptivity despite the intriguing situation in most Proteaceae of auto-deposition of self-pollen on or near stigmas at anthesis. Studies suggest that stigmas are not receptive until 0.5–4 days after anthesis. Banksia species appear to show low levels of self-compatibility although one subspecies shows high levels of selfing and evidence of selective fruit development. Self-compatibility may be more common in other genera, although a dearth of studies precludes generalisation. Assessment of mating systems indicates almost complete outcrossing for most species, lending support to the idea of selective fruit development. It is clear that many further studies of all topics are required but particularly across a wide range of genera because many have not been studied at all.

Returns to education in Russia: Nowhere below?

2021 ◽  
pp. 37-68
Author(s):  
R. I. Kapeliushnikov
Keyword(s):  
Returns To Education ◽  
Tertiary Education ◽  
Economic Value ◽  
Short Cycle ◽  
The Past ◽  
Monitoring Survey ◽  
Low Levels ◽  
Alternative Sources ◽  
Using Data ◽  
Russian Education

The paper presents a wide set of estimates for returns to education in Russia, introducing a number of new sources of microdata that previosly remained unused by both Russian and foreign researchers. Until now virtually all available estimates for Russia were based on data from a single source — The Russia Longitudinal Monitoring Survey — Higher School of Economics (RLMS-HSE). According to these data, since the mid-2000s returns to education rapidly declined and have dropped to abnormally low levels. The paper tests the thesis of ultra-low economic value of Russian education using data from three alternative representative surveys regularly conducted by Rosstat. The analysis shows that currently returns to education in Russia reach 12—13%, which is much higher than the standard RLMS estimates. University-type tertiary education almost doubles earnings (its premium approaches to 100%), and even short-cycle tertiary education provides a premium of about 20—30%. Alternative sources also indicate that over the past 15 years, returns to education in Russia remained stable and, therefore, no decreasing trend in the economic value of education has been observed. This makes it possible to reject the currently popular thesis about abnormally low returns to education in Russia.

Is There Population with Tertiary Education in Romania Still Interested in Research?

2015 ◽  
Vol 4 (4) ◽  
pp. 54-66
Author(s):  
Radu Serban Zaharia ◽  
Marian Zaharia ◽  
Alecu Alexandra
Keyword(s):  
Negative Impact ◽  
Tertiary Education ◽  
Government Policies ◽  
Total Employment ◽  
The Past ◽  
Education And Health ◽  
Material Basis ◽  
Labour Costs ◽  
Low Levels ◽  
The Government

In the past 25 years, in Romania, the intensity of R & D activities has declined significantly in most industries. This trend was driven primarily by the lower attention of the government policies of governments after 1990, resulting in particularly low share of research spending in GDP. This had a double negative impact. On one side was affected material basis of research, while on the other side salary levels of researchers along with education and health, remained at very low levels. Based on these considerations the paper examines the evolution of percentage of researchers in total employment in correlation with factors as: the percentage of population with tertiary educational attainment level, the percentage of total intramural R&D expenditure in GDP, the percentage of R&D labour costs in GDP in Romania, compared to Bulgaria, Czech Republic, France, Hungary and Poland. Unfortunately, in what concerns us, the answer is negative.

scholarly journals Tuberculosis Problem In Dakahlia Governorate, Egypt

2013 ◽  
Vol 10 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Amina Mostafa Abdel Aal ◽  
Noha El-Mashad ◽  
Dalia Magdi
Keyword(s):  
Age Groups ◽  
Public Health Problem ◽  
The Body ◽  
World Health ◽  
Tuberculosis Control ◽  
Important Public Health Problem ◽  
The Past ◽  
Chest Disease ◽  
Low Levels ◽  
Compliance To Treatment

Tuberculosis (TB) is a potentially fatal contagious disease that can affect almost any part of the body but is mainly an infection of the lungs. It has been present in humans since antiquity. In the past, tuberculosis has been called consumption, because it seemed to consume people from within, with a bloody cough, fever, pallor, and long relentless wasting. In Egypt, TB constitutes the second most important public health problem after schistosomiasis. Although Egypt has relatively low levels of TB according to data from the World Health of Organization, 2005:66% of TB cases occur among the socially and economically productive age groups of 15 to 54 years. According to Ministry of Health and Population (MOHP), Egypt; tuberculosis control is carried out through 111 chest centers and 39 chest disease hospitals. Treatment failure accounts for 3%–5%of the treatment outcome of new smear positive cases and 13%–17% of retreated cases and this is due to non-compliance to treatment, defi cient health education to the patient, poor patient knowledge regarding the disease and diabetes mellitus as co-morbid. The incidence and prevalence of tuberculosis in Egypt has been declining due to increased efforts of the MOHP. Prevalence dropped from 88/100,000 population in 1990 to 24 in 2008, according to data from WHO. SAARC Journal of Tuberculosis, Lung Diseases & HIV/AIDS; 2013; X(1); 43-49 DOI: http://dx.doi.org/10.3126/saarctb.v10i1.8677

scholarly journals Shark–Cetacean trophic interaction, Duinefontein, Koeberg, (5 Ma), South Africa

2015 ◽  
Vol Volume 111 (Number 11/12) ◽  
Author(s):  
Romala Govender ◽  
Keyword(s):  
South Africa ◽  
Cause Of Death ◽  
West Coast ◽  
Trophic Interaction ◽  
The West ◽  
Carcharodon Carcharias ◽  
Inverted Position ◽  
Bite Marks ◽  
Shark Teeth ◽  
Long Time

Abstract This study forms part of a larger project to reconstruct the Mio-Pliocene marine palaeoenvironment along South Africa’s west coast. It documents the shark–cetacean trophic interaction during the Zanclean (5 Ma) at Duinefontein (Koeberg). The damage described on the fragmentary cetacean bones was compared with similar damage observed on fossils from Langebaanweg, a Mio-Pliocene site on the west coast of South Africa, and data present in the literature. This comparison showed that the damage was the result of shark bites. The state of preservation makes it difficult to determine if the shark bite marks were the cause of death or as a result of scavenging. The presence of the bite marks on the bone would, however, indicate some degree of skeletonisation. Bite marks on some cranial fragments would suggest that the cetacean’s body was in an inverted position typical of a floating carcass. The preservation of the material suggests that the bones were exposed to wave action resulting in their fragmentation as well as abrasion, polishing and rolling. It also suggests that the cetacean skeletons were exposed for a long time prior to burial. The morphology of the bites suggests that the damage was inflicted by sharks with serrated and unserrated teeth. Shark teeth collected from the deposit include megalodon (Carcharodon megalodon), white (Carcharodon carcharias) as well as mako (Isurus sp. and Cosmopolitodus hastalis) sharks, making these sharks the most likely predators/scavengers.

Interpreting Sensor Data Using Continuous Wavelet Transformations

2004 ◽  
Author(s):  
Stephanie A. Wimmer ◽  
Virginia G. DeGiorgi
Keyword(s):  
Wavelet Transformation ◽  
Sensor Data ◽  
Structural Performance ◽  
Continuous Wavelet ◽  
Performance Parameters ◽  
Element Analysis ◽  
Health Monitoring System ◽  
The Past ◽  
Time Histories ◽  
Low Levels

Structural monitoring systems consist of a method to measure the structure’s performance at a given point in time to produce raw sensor data and the interpretation of this data in terms of presence and location of damage. This work focuses on the interpretation. The raw sensor data needs to be examined to indicate when further inspection is necessary, prior to the degradation of key structural performance parameters. Finding low levels of damage is critical to the development of a health monitoring system. This paper describes the use of the continuous wavelet transformation in the identification of damaged plates. Strain time histories are used in the algorithm. The strain histories are measured experimentally. In the past the authors have used finite element analysis to generate virtual sensor data. The authors track how the wavelet maximas change as damage accumulates. Various excitations are used to determine their affect.

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