4,147 research outputs found
Pricing Excess-of-loss Reinsurance Contracts Against Catastrophic Loss
This paper develops a pricing methodology and pricing estimates for the proposed Federal excess-of- loss (XOL) catastrophe reinsurance contracts. The contracts, proposed by the Clinton Administration, would provide per-occurrence excess-of-loss reinsurance coverage to private insurers and reinsurers, where both the coverage layer and the fixed payout of the contract are based on insurance industry losses, not company losses. In financial terms, the Federal government would be selling earthquake and hurricane catastrophe call options to the insurance industry to cover catastrophic losses in a loss layer above that currently available in the private reinsurance market. The contracts would be sold annually at auction, with a reservation price designed to avoid a government subsidy and ensure that the program would be self supporting in expected value. If a loss were to occur that resulted in payouts in excess of the premiums collected under the policies, the Federal government would use its ability to borrow at the risk-free rate to fund the losses. During periods when the accumulated premiums paid into the program exceed the losses paid, the buyers of the contracts implicitly would be lending money to the Treasury, reducing the costs of government debt. The expected interest on these "loans" offsets the expected financing (borrowing) costs of the program as long as the contracts are priced appropriately. By accessing the Federal government's superior ability to diversify risk inter-temporally, the contracts could be sold at a rate lower than would be required in conventional reinsurance markets, which would potentially require a high cost of capital due to the possibility that a major catastrophe could bankrupt some reinsurers. By pricing the contacts at least to break even, the program would provide for eventual private-market "crowding out" through catastrophe derivatives and other innovative catastrophic risk financing mechanisms. We develop prices for the contracts using two samples of catastrophe losses: (1) historical catastrophic loss experience over the period 1949-1994 as reported by Property Claim Services; and (2) simulated catastrophe losses based on an engineering simulation analysis conducted by Risk Management Solutions. We used maximum likelihood estimation techniques to fit frequency and severity probability distributions to the catastrophic loss data, and then used the distributions to estimate expected losses under the contracts. The reservation price would be determined by adding an administrative expense charge and a risk premium to the expected losses for the specified layer of coverage. We estimate the expected loss component of the government's reservation price for proposed XOL contracts covering the entire U.S., California, Florida, and the Southeast. We used a loss layer of $25-50 billion for illustrative purposes.
What am I gonna do with my life?: Exploring the transitional experiences of former Division 1 Black, male, first-generation college basketball and football student-athletes into the world of work
The transition into the world of work for Division 1 student-athletes is important because there are slim chances to achieve a professional athletic playing career. This research study aims to explore the career transitional experiences of former Division 1 Black, male, first-generation college basketball and football student-athletes as they hold overrepresented identities in Division 1 basketball and football. Specifically, the research aims to address these questions: (1) What factors affect how former Division 1 Black, male, first-generation college basketball and football student-athletes navigate their transition from sport into sport-related careers not involving competitive athletic play? (2) What factors affect how former Division 1 Black, male, first-generation college basketball and football student-athletes navigate their transition from sport into nonsport- related careers? Data collection occurred through 70- to 110-minute semi-structured interviews with 7 former Division 1 Black, male, first-generation college basketball and football student-athletes. Interviews shared during college and after college experiences that shaped their transition into sport-related and non-sport-related careers. Findings from this study presented five emergent themes addressing the research questions: (1) Athletic Identity Reinforcement, (2) Lack of Self-Directed Choices, (3) Connection through Identifiable Spaces, (4) Village-Based Support, and (5) Career Decision-Making Difficulties. These findings illustrate the complications of pursuing career planning while participating in Division 1 basketball and football.Includes bibliographical references
Futility, appropriate care, and orders not to resuscitate: Who makes decisions and how?
Ethical issues in resuscitation arose once life-prolonging interventions advanced to the point where short-term cardiac resuscitation became plausible in patients in cases where imminent death was irreversible. The authors argue that ethical dilemmas arise from disputes over continued treatment when stakeholders either disagree about the meaning of appropriate care as a result of differing beliefs on the meaning of an acceptable outcome and/or the extent of a treatmentâs probable efficacy. The authors conclude that even though communication and transparency can help prevent these ethical dilemmas, unavoidable conflict over proper interventions should be resolved through a decision-making process grounded in both medical reality and the principles of patient self-determination. Thoughtful regulatory guidance can aid the understanding of rights and responsibilities when the desirability, efficacy, and medical indication of life-prolonging interventions are in dispute. The authors outline such a process. The authors suggest that seeking clear regulation in this arena is a worthwhile ethical and practical objective for physicians to reduce both the likelihood of conflicts and the burden of unavoidable conflicts despite transparency and communication
Revisiting N\'eel 60 years on: the magnetic anisotropy of FeNi (tetrataenite)
The magnetocrystalline anisotropy energy of atomically ordered
FeNi (the meteoritic mineral tetrataenite) is studied within a
first-principles electronic structure framework. Two compositions are examined:
equiatomic FeNi and an Fe-rich composition,
FeNi. It is confirmed that, for the single crystals modelled
in this work, the leading-order anisotropy coefficient dominates the
higher-order coefficients and . To enable comparison with
experiment, the effects of both imperfect atomic long-range order and finite
temperature are included. While our computational results initially appear to
undershoot the measured experimental values for this system, careful scrutiny
of the original analysis due to N\'{e}el et al. [J. Appl. Phys. 35, 873 (1964)]
suggests that our computed value of is, in fact, consistent with
experimental values, and that the noted discrepancy has its origins in the
nanoscale polycrystalline, multivariant nature of experimental samples, that
yields much larger values of and than expected a priori. These
results provide fresh insight into the existing discrepancies in the literature
regarding the value of tetrataenite's uniaxial magnetocrystalline anisotropy in
both natural and synthetic samples.Comment: 9 pages, 3 figures, 2 table
The effects of river flooding on dioxin and PCBs in beef
In 2008-2010, samples of meat from 40 beef cattle, along with grass, soil and commercial feed, taken from ten matched pairs of flood-prone and control farms, were analysed for PCDD/Fs and PCBs. Concentrations were higher in soil and grass from flood-prone farms. The beef samples from flood-prone farms had total TEQ levels about 20% higher than on control farms. A majority of flood-prone farms (7/10) had higher median levels in beef than on the corresponding control farm. This first controlled investigation into PCDD/F and PCB contamination in beef produced on flood-prone land, presents robust evidence that flooding is a contaminant transfer mechanism to cattle raised on river catchments with a history of urbanisation and industrialisation. PCDD/F and PCB sources in these river systems are likely to be a result of the legacy of contamination from previous industrialisation, as well as more recent combustion activity or pollution events. Crow
Integrated ab initio modelling of atomic order and magnetic anisotropy for rare-earth-free magnet design: effects of alloying additions in FeNi
We describe an integrated modelling approach to accelerate the search for
novel, single-phase, multicomponent materials with high magnetocrystalline
anisotropy (MCA). For a given system we predict the nature of atomic ordering,
its dependence on the magnetic state, and then proceed to describe the
consequent MCA. Crucially, within our modelling framework, the same ab initio
description of the material's electronic structure determines both aspects. We
demonstrate this holistic method by studying the effects of alloying additions
in FeNi, examining systems with the general stoichiometry FeNi,
including Pt, Pd, Al, and Co. The atomic ordering behaviour predicted on
adding these elements, fundamental for determining a material's MCA, is rich
and varied. Equiatomic FeNi has been reported to require ferromagnetic order to
establish the tetragonal order suited for significant MCA. Our
results show that when alloying additions are included in this material,
annealing in an applied magnetic field and/or below a material's Curie
temperature may also promote tetragonal order, along with an appreciable effect
on the predicted MCA.Comment: 13 pages, 6 figures, 3 table
Novel pyrrolobenzodiazepine benzofused hybrid molecules inhibit NF-ÎșB activity and synergise with bortezomib and ibrutinib in hematological cancers
Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are incurable hematological malignancies that are pathologically linked with aberrant NF-ÎșB activation. In this study, we identified a group of novel C8-linked benzofused Pyrrolo[2,1-c][1,4]benzodiazepines (PBD) monomeric hybrids capable of sequence-selective inhibition of NF-ÎșB with low nanomolar LD50 values in CLL (n=46) and MM cell lines (n=5). The lead compound, DC-1-192, significantly inhibited NF-ÎșB DNA binding after just 4h exposure and demonstrating inhibitory effects on both canonical and non-canonical NF-ÎșB subunits. In primary CLL cells, sensitivity to DC-1-192 was inversely correlated with RelA subunit expression (r2=0.2) and samples with BIRC3 or NOTCH1 mutations showed increased sensitivity (P=0.001). RNA-sequencing and gene set enrichment analysis confirmed the over-representation of NF-ÎșB regulated genes in the down-regulated gene list. Furthermore, In vivo efficacy studies in NOD/SCID mice, using a systemic RPMI 8226 human multiple myeloma xenograft model, showed that DC-1-192 significantly prolonged survival (P=0.017). In addition, DC1-192 showed synergy with bortezomib and ibrutinib; synergy with ibrutinib was enhanced when CLL cells were co-cultured on CD40L-expressing fibroblasts in order to mimic the cytoprotective lymph node microenvironment (P = 0.01). Given that NF-ÎșB plays a role in both bortezomib and ibrutinib resistance mechanisms, these data provide a strong rationale for the use of DC-1-192 in the treatment of NF-ÎșB-driven cancers, particularly in the context of relapsed/refractory disease
Origin of the thiopyrone CTP-431 âunexpectedlyâ isolated from the marine sponge Cacospongia mycofijiensis
An intriguing hypothesis that latrunculin A, a well-known natural product, might have undergone transformation into the unprecedented thiopyrone CTP-431 upon long-term storage in methanol is advanced. Thus opening of the hemiacetal of latrunculin A, followed by E1CB elimination, and dehydration would give a polyene that could undergo intramolecular Diels-Alder reaction, followed by methanolysis of the thiazolidinone ring and ring closure by intramolecular thiol addition to an enone. Experimental evidence that the novel thiazolidinone to thiopyrone rearrangement can occur is presented.The marine sponge Cacospongia mycofijiensis, found in the ocean surrounding Fiji, is a source of several polyketide natural products with interesting biological properties,1 including the tubulin binding macrolide fijianolide B (also known as laulimalide),2,3 the HIF1 signal inhibitor mycothiazole,4,5 and the macrolide latrunculins (Figure 1).6 The thiazolidinone-containing latruculins are of mixed polyketide synthesis (PKS) and non-ribosomal peptide synthesis (NRPS) origin, and latrunculin A 1 disrupts microfilament assembly to such an extent that it is the most widely used chemical tool to study actin binding
Interplay between magnetism and short-range order in medium- and high-entropy alloys: CrCoNi, CrFeCoNi, and CrMnFeCoNi
The impact of magnetism on predicted atomic short-range order in three
medium- and high-entropy alloys is studied using a first-principles,
all-electron, Landau-type linear response theory, coupled with lattice-based
atomistic modelling. We perform two sets of linear-response calculations: one
in which the paramagnetic state is modelled within the disordered local moment
picture, and one in which systems are modelled in a magnetically ordered state,
which is ferrimagnetic for the alloys considered in this work. We show that the
treatment of magnetism can have significant impact both on the predicted
temperature of atomic ordering and also the nature of atomic order itself. In
CrCoNi, we find that the nature of atomic order changes from being
-like when modelled in the paramagnetic state to MoPt-like
when modelled assuming the system has magnetically ordered. In CrFeCoNi, atomic
correlations between Fe and the other elements present are dramatically
strengthened when we switch from treating the system as magnetically disordered
to magnetically ordered. Our results show it is necessary to consider the
magnetic state when modelling multicomponent alloys containing mid- to
late- elements. Further, we suggest that there may be high-entropy alloy
compositions containing transition metals that will exhibit specific
atomic short-range order when thermally treated in an applied magnetic field.
This has the potential to provide a route for tuning physical and mechanical
properties in this class of materials.Comment: 26 pages, 4 figures, 2 table
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