Three-point compound sine plate offers cost and weight savings

Work piece adjustment fixture reduces size, weight and set-up complexity of alignment platforms used in metal blank machining. Design benefits designers and manufacturers of machine tools and measuring equipment

Experience Implementing a Performant Category-Theory Library in Coq

We describe our experience implementing a broad category-theory library in Coq. Category theory and computational performance are not usually mentioned in the same breath, but we have needed substantial engineering effort to teach Coq to cope with large categorical constructions without slowing proof script processing unacceptably. In this paper, we share the lessons we have learned about how to represent very abstract mathematical objects and arguments in Coq and how future proof assistants might be designed to better support such reasoning. One particular encoding trick to which we draw attention allows category-theoretic arguments involving duality to be internalized in Coq's logic with definitional equality. Ours may be the largest Coq development to date that uses the relatively new Coq version developed by homotopy type theorists, and we reflect on which new features were especially helpful.Comment: The final publication will be available at link.springer.com. This version includes a full bibliography which does not fit in the Springer version; other than the more complete references, this is the version submitted as a final copy to ITP 201

Land Law in Burundi: Legal and Social Ordering of Land Tenure in Historical and Contemporary Burundi.

The thesis deals with Burundi land tenure (i) historically, with an analysis of reports, recorded cases and oral accounts relating to the colonial era, and (ii) contemporaneously with a description of selected land disputes. These data form the basis of an appraisal of Governmental ideas on land law reform. In Burundi rights in land may originate either in written or customary law or in instruments established by administrative authorities. The main objective of written law enacted during the colonial period was to regulate the relationships between Africans, the State and colonists concerning land, ensuring the security of tenure of the colonists through a system of leases and freeholds. After Independence most colonial Acts were kept in force. At present, only a minute part of the territory, mostly in urban areas, is governed by written law, whereas most land is still held according to customary law which defines with great precision the various interests individuals and groups may have in land. Finally, in urban areas and in rural settlement schemes, colonial and Burundi administrative authorities have granted interests in land known as "droits d'occupation". In 1978, the Government devised a project of land law reform based on the view that all forms of tenure should be converted to tenure under written law as organized by the Civil Code. This project represents a form of cultural alienation. Colonial law was enacted to fit the colonial situation; the first step to land law reform is therefore not the conversion of tenure, but a rethinking of the relationships between men regarding land in contemporary Burundi, leading to the enactment of new rules which will take into account the various existing systems of land tenure, the various social and economic functions of land, and the development objectives of the Government

Isolated Late Metastasis of a Renal Cell Cancer Treated by Radical Distal Pancreatectomy

A 53–year-old man underwent right nephrectomy for a locally advanced renal cell carcinoma with concomitant resection of a solitary metastasis in the right lung. Ten years later, he presented with haematochezia caused by a tumour in the tail of pancreas, invading the transverse colon and the greater curvature of the stomach. The tumour was radically resected, and histological examination revealed a solitary metastasis of the previous renal cell carcinoma. This case illustrates a rare indication for pancreatic resection because of pancreatic metastasis

The dynamics of unsteady frictional slip pulses

Self-healing slip pulses are major spatiotemporal failure modes of frictional systems, featuring a characteristic size $L(t)$ and a propagation velocity $c_{\rm p}(t)$ ($t$ is time). Here, we develop a theory of slip pulses in realistic rate-and-state dependent frictional systems. We show that slip pulses are intrinsically unsteady objects, yet their dynamical evolution is closely related to their unstable steady-state counterparts. In particular, we show that each point along the time-independent L^{\mbox{{(0)}}}\!(\tau_{\rm d})\!-\!c^{\mbox{{(0)}}}_{\rm p}\!(\tau_{\rm d}) line, obtained from a family of steady-state pulse solutions parameterized by the driving shear stress $\tau_{\rm d}$, is unstable. Nevertheless, and remarkably, the c^{\mbox{{(0)}}}_{\rm p}[L^{\mbox{{(0)}}}] line is a dynamic attractor such that the unsteady dynamics of slip pulses -- whether growing ($\dot{L}(t)\!>\!0$) or decaying ($\dot{L}(t)\!<\!0$) -- reside on the steady-state line. The unsteady dynamics along the line are controlled by a single slow unstable mode. The slow dynamics of growing pulses, manifested by $\dot{L}(t)/c_{\rm p}(t)\!\ll\!1$, explain the existence of sustained pulses, i.e.~pulses that propagate many times their characteristic size without appreciably changing their properties. Our theoretical picture of unsteady frictional slip pulses is quantitatively supported by large-scale, dynamic boundary-integral method simulations.Comment: 6 pages, 4 figures + Supplemental Material

The tobacco industry's past role in weight control related to smoking

Background: Smoking is thought to produce an appetite-suppressing effect by many smokers. Thus, the fear of body weight gain often outweighs the perception of health benefits associated with smoking cessation, particularly in adolescents. We examined whether the tobacco industry played a role in appetite and body weight control related to smoking and smoking cessation. Methods: We performed a systematic search within the archives of six major US and UK tobacco companies (American Tobacco, Philip Morris, RJ Reynolds, Lorillard, Brown & Williamson and British American Tobacco) that were Defendants in tobacco litigation settled in 1998. Findings are dated from 1949 to 1999. Results: The documents revealed the strategies planned and used by the industry to enhance effects of smoking on weight and appetite, mostly by chemical modifications of cigarettes contents. Appetite-suppressant molecules, such as tartaric acid and 2-acetylpyridine were added to some cigarettes. Conclusion: These tobacco companies played an active and not disclaimed role in the anti-appetite effects of smoking, at least in the past, by adding appetite-suppressant molecules into their cigarette

Bayesian estimation of tobramycin exposure in cystic fibrosis

Fixed tobramycin (mg/kg) dosing is often inappropriate in patients with cystic fibrosis (CF), as pharmacokinetics are highly variable. The area under the concentration-time curve (AUC) is an exposure metric suited to monitoring in this population. Bayesian strategies to estimate AUC have been available for over 20 years but are not standard practice in the clinical setting. To assess their suitability for use in clinical practice, three AUC estimation methods using limited sampling were compared to measured true exposure by using intensive sampling tobramycin data. Adults prescribed once daily intravenous tobramycin had eight concentrations taken over 24 h. An estimate of true exposure within one dosing interval was calculated using the trapezoidal method and compared to three alternate estimates determined using (i) a two-sample log-linear regression (LLR) method (local hospital practice); (ii) a Bayesian estimate using one concentration (AUC(1)); and (iii) a Bayesian estimate using two concentrations (AUC(2)). Each method was evaluated against the true measured exposure by a Bland-Altman analysis. Twelve patients with a median (range) age and weight of 25 (18 to 36) years and 66.5 (51 to 76) kg, respectively, were recruited. There was good agreement between the true exposure and the three alternate estimates of AUC, with a mean AUC bias of < 10 mg/liter center dot h in each case, i.e., -8.2 (LLR), 3.8 (AUC(1)), and 1.0 (AUC(2)). Bayesian analysis-based and LLR estimation methods of tobramycin AUC are equivalent to true exposure estimation. All three methods may be suitable for use in the clinical setting; however, a one-sample Bayesian method may be most useful in ambulatory patients for which coordinating blood samples is difficult. Suitably powered, randomized clinical trials are required to assess patient outcomes

Experimental calibration of Mn incorporation in foraminiferal calcite

International audienc

Black Vulture Conflict and Management in the United States: Damage Trends, Management Overview, and Research Needs

Contrary to rapid declines of many vulture (Accipitridae, Cathartidea) species worldwide, black vulture (Coragyps atratus) populations are increasing and expanding their range in North America. Vultures exhibit complex behaviors and can adapt to any human-dominated landscape or land use. These traits, combined with population growth and range expansion, have contributed to increased human–vulture conflicts. Our goal was to summarize the current status and trends in human–black vulture conflicts (hereafter human–vulture conflicts), review available management strategies, identify knowledge gaps, and provide recommendations to enhance management and understanding of this species and the associated conflicts. We found human–vulture conflicts are increasing in agriculture (livestock), private and public property (both personal and infrastructure-based), and threats to human health and safety. The greatest increases in conflicts were reported in agriculture and private and public property damage. Regarding livestock depredation, good progress has been made toward assessing producer perceptions of the conflicts, including estimates of economic damage and mitigation strategies, but a basic understanding of the underlying mechanism driving the conflict and advancing strategies to mitigate damage is lacking. For damaged property, little information is available regarding economic losses and perceptions of stakeholders who are experiencing the damage, and most of the tools recommended for mitigating this damage have not been rigorously evaluated. Regarding human health and safety, recent research quantifying flight behavior of black vultures has direct implications for reducing aircraft collision risks. However, it is unclear what factors influence roost site selection and the most effective means to leverage the sensory ecology of the species to mitigate risks. We identify additional knowledge gaps and research needs that if addressed could increase managers’ understanding of black vulture ecology and facilitate enhanced management of this species while simultaneously allowing for the species to provide valuable ecosystem services