2,769 research outputs found
Characterising carbon cycle perturbations in the Cenomanian western interior seaway of North America
No full textAs current global temperatures continue to rise at an accelerated pace, it is becoming increasingly important to examine how the planet has responded to previous periods of global warming in order to gain valuable insights into how the Earth system may react in the future. The mid-Cretaceous (~101-91 Ma) provides an excellent case study of a prolonged greenhouse climatic state, where high rates of oceanic crust production and enhanced large igneous province-related volcanism released vast quantities of greenhouse gases into the atmosphere. Consequently, global temperatures reached their highest level for the past 450 Myr during the Cenomanian to Turonian stages, and peak sea levels led to the development of epeiric seas such as the Western Interior Seaway (WIS), which extended southwards from the northern Boreal Ocean, across central North America, and into the Tethys Ocean. Superimposed upon this greenhouse climate were a series of even more extreme climate perturbations, of which Oceanic Anoxic Event 2 (OAE 2), spanning the Cenomanian-Turonian boundary (94.1 Ma), was the most prominent, globally widespread, extreme climatic event of the Late Cretaceous. OAE 2 represents a major global carbon cycle perturbation, during which enhanced marine productivity coupled with the expansion of oxygen minimum zones across global oceans led to the extensive deposition of organic-rich black shale deposits. An earlier Mid-Cenomanian Event (MCE I; ~96.5 Ma) is taken to be a precursor to OAE 2, as it marks the beginning of a ~2 Myr oceanographic reorganisation during which bottom waters started to become increasingly oxygen-depleted. MCE I is identified on a global scale by a distinct dual-peaked positive carbon isotope excursion. However, with little evidence of widespread organic-rich mudrock deposition, most studies of MCE I are from carbonate-rich successions, thus limiting the range of analyses that can be undertaken. Here, a high-resolution, integrated organic and inorganic multi-proxy study of the Rebecca K Bounds-1 core from western Kansas has been undertaken in order to elucidate environmental and oceanographic changes during MCE I and the interval leading up to OAE 2 in the central-eastern WIS. MCE I is identified in an organic-rich sequence through a dual-peaked, positive organic carbon isotope excursion (MCE 1a and MCE 1b, respectively), and is determined to coincide with the establishment of a fully connected seaway that extended from the northern Boreal Ocean to the Tethyan Ocean in the south via the WIS in the mid-Cenomanian, as evidenced by diversified palynological, foraminiferal, and geochemical changes between MCE 1a and MCE 1b. Periodically enhanced planktic productivity is linked to ~50 kyr obliquity cycles across MCE I through cyclostratigraphic analysis. This heightened productivity is attributed to the strengthening of meridional winds during obliquity maxima, which may have increased upwelling-related nutrient input into Tethyan surface waters in equatorial regions. Palynological, redox-sensitive trace metal, lipid biomarker, and sedimentological data reveal that a complex dynamic oceanographic system prevailed in the central region of the WIS, with mixed early Cenomanian Tethyan-Boreal waters eventually being replaced by a northward migrating Tethyan water mass in the mid- to late Cenomanian. This situation prevailed until OAE 2 set in, when a rapid southward incursion of Boreal waters extended as far as the southern margin of the seaway. This multi-faceted study provides a new in-depth, high-resolution example of how Earth systems and environmental conditions reacted to periods of stressed, greenhouse climatic conditions
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The IAAF’s hyperandrogenism regulations suspended
No full textOn 27 July, the Court of Arbitration for Sport (‘CAS’) delivered a landmark ruling on the regulation of gender in sport. The decision explores how the categorisation of sport on the basis of sex can be best reconciled with the “biological reality” that human sex cannot necessarily be divided so clearly. Dr. Seema Patel, Senior Lecturer at Nottingham Trent University, Deputy Director of the Centre for Sports Law and author of ‘Inclusion and Exclusion in Competitive Sport: Socio-Legal and Regulatory Perspectives,’ reviews the case and suggests that sport regulation must be cautious of traditional criteria to determine eligibility in sports
Author interview: Q and A with Dr Ian Sanjay Patel on we’re here because you were there: immigration and the end of empire
No full textIn this author interview, we speak to Dr Ian Sanjay Patel about his new book, We’re Here Because You Were There: Immigration and the End of Empire, which explores post-war immigration laws, the afterlives of British imperial citizenship and related attempts to reimagine and rejuvenate British imperialism after 1945. Contributing to transnational histories of decolonisation, the book also explores the interconnections between human rights, post-war migration and international diplomacy. Author Interview with Dr Ian Sanjay Patel, author of We’re Here Because You Were There: Immigration and the End of Empire. Verso. 2021
Embedded in the Body: the Poetry, History and Politics of Migritude with Shailja Patel (2021-02-25)
No full textOnline discussion, reading and Q&A; Thursday, February 25 at 4:00PM CST; Shailja Patel is the bestselling author of Migritude, taught in over 100 colleges and universities worldwide. Patel's poems have been translated into 17 languages, and been featured in the Smithsonian. The Nobel Women's Initiative honored her with a Global Feminist Spotlight. She is currently a Research Associate at Five College Women's Studies Research Center.Women, Gender & Sexuality Studies program; Alworth Institute for International Studies; Department of Anthropology, Sociology & Criminology; English program; Writing Studies programPatel, Shailja. (2021). Embedded in the Body: the Poetry, History and Politics of Migritude with Shailja Patel (2021-02-25). Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/220654
The Patel trials: further evidence of the need to reform the Griffith Codes
No full textThis article argues that the two trials of Dr Jayant Patel for criminal medical negligence under s 288 of the Criminal Code 1899 Act (Qld) highlight the inadequacies of the duty provisions in the Griffith Codes of Queensland and Western Australia. The difficulties with these duty provisions extend beyond causation and go to the heart of the construction of the Griffith Codes. The fundamental problem lies in the wording of s 23 of both the Queensland and
the Western Australia Codes, the principal section dealing with criminal responsibility, which allows a prosecution for criminal negligence under two alternative routes with different standards of proof, and the importation of
common law criminal negligence into the duty provisions in the absence of a specified fault element in the relevant Code sections. It is further contended that other criminal law jurisdictions in Australia, such as the Criminal Code
1995 (Cth), offer a better model for the prosecution of criminal negligence cases that flow from breach of a specified duty. The article has greatly benefited from comments provided to the author by Justice HG Fryberg, who
conducted the second Patel trial
Yogesh Prajapat 1.pmd
No full textABSTRACT Chalones, 2,4-bis-(4'-flurophenylamino)-6-[4'-{3"-(substituted phenyl/2"'-furanyl)-2"-propenon-1"-yl} phenylamino] s-triazine (6a-e) have been prepared from ketone (5) on treatment with different aromatic/hetarocyclic aldehydes. These chalcones on cyclisation with guandiine nitrate in presence of alkali and malononitrile in presence of ammonium acetate give the corresponding aminopyrimidine (7a-e) and cyanopyridine (8a-e) derivatives respectively. All the synthesized compounds have been screened for their antibacterial activity against S. aureus (MTCC 96), B. subtilis (MTCC 441), E. coli (MTCC 443) and S. paratyphi-B. (MTCC 733). The structure of the synthesized compounds have been established on the basis of their elemental analysis and spectral studies
dc121p-patel
No full textAbstract Researchers have used machine learning algorithms to solve hard problems in a variety of domains, enabling exciting, new applications of computing. However, research results have not transferred to software solutions. In part, this is because developing software with machine learning algorithms is itself difficult. My dissertation work aims to understand why using machine learning is difficult and to create tools that lower the bar so that more developers can effectively use machine learning
Numerical simulation and modeling of microdroplet evaporation
No full textSubmission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-11 without embargo termsThe student, Ankit Patel, accepted the attached license on 2022-04-20 at 15:06.The student, Ankit Patel, submitted this Thesis for approval on 2022-04-20 at 15:10.This Thesis was approved for publication on 2022-04-27 at 16:12.DSpace SAF Submission Ingestion Package generated from Vireo submission #17858 on 2022-11-11 at 13:42:36The ability to understand and quantify droplet evaporation and its associated heat and mass transport is extremely valuable to a variety of industries such as, and not limited to, combustion, energy systems, computer technology, thermal management systems, and advanced manufacturing. The primary reason for this value is derived from the ability for droplets to absorb high heat fluxes across relatively small length scales and efficiently transport that energy by using their latent heat of vaporization. With this intrinsic value proposition, it is imperative to be able to numerically model and predict this complex phenomenon to design and invent solutions that will help drive a variety of industries forward. In this thesis, a numerical model is developed which is capable of prediction evaporation of liquid microdroplets. Using previously established and verified experimental results, various numerical models and simulation approaches were investigated and the results ultimately compared to determine the most optimal numerical modeling methodology. Ultimately, the work completed within this thesis serves as a foundation for future studies into the complex physical mechanisms governing evaporation and condensation at the liquid-vapor interfaces
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