Direct Causation: A New Approach to an Old Question

Causative constructions come in lexical and periphrastic variants, exemplified in English by Sam killed Lee and Sam caused Lee to die. While use of the former, the lexical causative, entails the truth of the latter, an entailment in the other direction does not hold. The source of this asymmetry is commonly ascribed to the lexical causative having an additional prerequisite of “direct causation , such that the causative relation holds between a contiguous cause and effect (Fodor 1970, Katz 1970). However, this explanation encounters both empirical and theoretical problems (Nelleman & van der Koot 2012). To explain the source of the directness inferences (as well as other longstanding puzzles), we propose a formal analysis based on the framework of Structural Equation Models (SEMs) (Pearl 2000) which provides the necessary background for licensing causal inferences. Specifically, we provide a formalization of a \u27sufficient set of conditions\u27 within a model and demonstrate its role in the selectional parameters of causative descriptions. We argue that “causal sufficiency” is not a property of singular conditions, but rather sets of conditions, which are individually necessary but only sufficient when taken together (a view originally motivated in the philosophical literature by Mackie 1965). We further introduce the notion of a “completion event” of a sufficient set, which is critical to explain the particular inferential profile of lexical causatives

Impact of wolf (Canis lupus) on animal husbandry in an Apennine province

Predation has always been an important problem in extensive sheep farms, causing serious economic losses to the farmers. In the Province of Lucca, the presence of reproductive wolf packs has already been confirmed in natural reserves, but occasional signs of presence of the predator have been reported also in neighbouring areas. The present research has been carried out in this Province (between the Orecchiella Natural Reserve and the medium Serchio Valley), in order to obtain more complete information on the location of the wolf (with transects, wolf- howling and snow-tracking), and to verify the real impact and risk factors of predation on live- stock (by means of on-farm surveys carried out in 42 semi-extensive farms) in this area. The presence of wolf was confirmed in the study area with a minimum of four adult individuals and at least one pup: this pack lives around the peaks of the Apennines in the municipalities covered by this investigation. A growing conflict between the wolf and the sheep and goat farms was observed: since 2007 there have been 25 attacks and three farms can be considered subject to chronic predation. The major risk factors are high altitude, large flock size and lack of fences and of guardian dogs. An accurate knowledge of wolf presence and the identification of the farms mostly at risk can be useful for future planning of interventions aimed at prevention and support of farmers, in order to mitigate the conflict caused by predation

The classical theory of calculus of variations for generalized functions

We present an extension of the classical theory of calculus of variations to generalized functions. The framework is the category of generalized smooth functions, which includes Schwartz distributions, while sharing many nonlinear properties with ordinary smooth functions. We prove full connections between extremals and Euler-Lagrange equations, classical necessary and sufficient conditions to have a minimizer, the necessary Legendre condition, Jacobi's theorem on conjugate points and Noether's theorem. We close with an application to low regularity Riemannian geometry

Impact of wolf (Canis lupus) on animal husbandry in an Apennine province

Predation has always been an important problem in extensive sheep farms, causing serious economic losses to the farmers. In the Province of Lucca, the presence of reproductive wolf packs has already been confirmed in natural reserves, but occasional signs of presence of the predator have been reported also in neighbouring areas. The present research has been carried out in this Province (between the Orecchiella Natural Reserve and the medium Serchio Valley), in order to obtain more complete information on the location of the wolf (with transects, wolfhowling and snow-tracking), and to verify the real impact and risk factors of predation on livestock (by means of on-farm surveys carried out in 42 semi-extensive farms) in this area. The presence of wolf was confirmed in the study area with a minimum of four adult individuals and at least one pup: this pack lives around the peaks of the Apennines in the municipalities covered by this investigation. A growing conflict between the wolf and the sheep and goat farms was observed: since 2007 there have been 25 attacks and three farms can be considered subject to chronic predation. The major risk factors are high altitude, large flock size and lack of fences and of guardian dogs. An accurate knowledge of wolf presence and the identification of the farms mostly at risk can be useful for future planning of interventions aimed at prevention and support of farmers, in order to mitigate the conflict caused by predation

A mixed-valence diruthenium(ii,iii) complex endowed with high stability: from experimental evidence to theoretical interpretation

We herein report the synthesis and multi-technique characterization of [Ru2Cl((2-phenylindol-3-yl)glyoxyl-l-leucine-l-phenylalanine)4], a novel diruthenium(ii,iii) complex obtained by reacting [Ru2(μ-O2CCH3)4Cl] with a dual indolylglyoxylyl dipeptide anticancer agent. We soon realised that the compound is very stable under several different conditions including aqueous buffers or organic solvents. It is also completely unreactive toward proteins. The high stability is also suggested by cellular experiments in a glioblastoma cell line. Indeed, while the parent ligand exerts high cytotoxic effects in the low μM range, the complex is completely non-cytotoxic against the same line, most probably because of the lack of ligand release. To investigate the reasons for such high stability, we carried out DFT calculations that are fully consistent with the experimental findings. The results highlight that the stability of [Ru2Cl((2-phenylindol-3-yl)glyoxyl-l-leucine-l-phenylalanine)4] relies on the nature of the ligand, including its steric hindrance that prevents the reaction of any nucleophilic group with the Ru2 core. Ligand displacement is the key step to allow reactivity with the biological targets of metal-based prodrugs. Accordingly, we discuss the implications of some important aspects that should be considered when active molecules are chosen as ligands for the synthesis of paddle-wheel-like complexes with medicinal applications. This journal i

Hypernatural Numbers as Ultrafilters

In this paper we present a use of nonstandard methods in the theory of ultrafilters and in related applications to combinatorics of numbers

Use of bivalirudin for heparin-induced thrombocytopaenia after thrombolysis in massive pulmonary embolism: a case report

A 68-year-old man was referred to the emergency department 6 h after onset of sudden acute dyspnoea. Immediate ECG showed sinus tachycardia with the typical S1-Q3-T3 pattern and incomplete right bundle branch block. The echocardiogram showed the presence of mobile thrombus in the right atrium, a distended right ventricle with free wall hypokinesia and displacement of the interventricular septum towards the left ventricle. Lung spiral computed tomography (CT) showed bilateral pulmonary involvement and confirmed the picture of a thrombotic system in the right atrium and caval vein. Thrombolytic treatment with recombinant tissue plasminogen activator (rt-PA) and heparin (alteplase 10 mg bolus, then 90 mg over 2 h) was administered. Six hours after thrombolysis bleeding gums and significant reduction in platelet count (around 50,000) were observed. Heparin was discontinued and bivalirudin (0.1 mg/kg bolus and 1.75 mg/kg per h infusion) plus warfarin was initiated and continued for 5 days until the international normalised ratio (INR) was within the therapeutic range (2.0–3.0) for 2 consecutive days, with concomitant platelet count normalisation. Lung spiral and lower abdominal CT before discharge did not show the presence of clots in the pulmonary arteries of the right and left lung. This case suggests that bivalirudin could offer promise for use in patients with heparin-induced thrombocytopaenia (HIT) after thrombolysis for massive pulmonary embolism

In-stent thrombosis after 68 months of implantation inspite of continuous dual antiplatelet therapy: a case report

Lately, there has been an increased incidence of late stent thrombosis; especially following Drug eluting stent (DES) implantation. Several factors are associated with an increased risk of stent thrombosis, including the procedure itself, patient and lesion characteristics, stent design, and premature cessation of anti-platelet drugs. We present a case of late stent thrombosis (LST) following DES implantation after a period of 68 months, making it the longest reported case of LST reported in the literature, despite the use of dual anti-platelet therapy

Spread pattern of the first dengue epidemic in the city of Salvador, Brazil

<p>Abstract</p> <p>Background</p> <p>The explosive epidemics of dengue that have been occurring in various countries have stimulated investigation into new approaches to improve understanding of the problem and to develop new strategies for controlling the disease. The objective of this study was to evaluate the characteristics of diffusion of the first dengue epidemic that occurred in the city of Salvador in 1995.</p> <p>Methods</p> <p>The epidemiological charts and records of notified cases of dengue in Salvador in 1995 constituted the source of data. The cases of the disease were georeferenced according to census areas (spatial units) and epidemiological weeks (temporal unit). Kernel density estimation was used to identify the pattern of spatial diffusion using the R-Project computer software program.</p> <p>Results</p> <p>Of the 2,006 census areas in the city, 1,400 (70%) registered cases of dengue in 1995 and the spatial distribution of these records revealed that by the end of 1995 practically the entire city had been affected by the virus, with the largest concentration of cases occurring in the western region, composed of census areas with a high population density and predominantly horizontal residences compared to the eastern region of the city, where there is a predominance of vertical residential buildings.</p> <p>Conclusion</p> <p>The pattern found in this study shows the characteristics of the classic process of spreading by contagion that is common to most infectious diseases. It was possible to identify the epicenter of the epidemic from which centrifugal waves of the disease emanated. Our results suggest that, if a more agile control instrument existed that would be capable of rapidly reducing the vector population within a few days or of raising the group immunity of the population by means of a vaccine, it would theoretically be possible to adopt control actions around the epicenter of the epidemic and consequently reduce the incidence of the disease in the city. This finding emphasizes the need for further research to improve the technology available for the prevention of this disease.</p