Expanding Our Grasp: Causal Knowledge and the Problem of Unconceived Alternatives

I argue that scientific realism, insofar as it is only committed to those scientific posits of which we have causal knowledge, is immune to Kyle Stanford’s argument from unconceived alternatives. This causal strategy (previously introduced, but not worked out in detail, by Anjan Chakravartty) is shown not to repeat the shortcomings of previous realist responses to Stanford’s argument. Furthermore, I show that the notion of causal knowledge underlying it can be made sufficiently precise by means of conceptual tools recently introduced into the debate on scientific realism. Finally, I apply this strategy to the case of Jean Perrin’s experimental work on the atomic hypothesis, disputing Stanford’s claim that the problem of unconceived alternatives invalidates a realist interpretation of this historical episode.

Estimating the number of motor units using random sums with independently thinned terms

The problem of estimating the numbers of motor units N in a muscle is embedded in a general stochastic model using the notion of thinning from point process theory. In the paper a new moment type estimator for the numbers of motor units in a muscle is denned, which is derived using random sums with independently thinned terms. Asymptotic normality of the estimator is shown and its practical value is demonstrated with bootstrap and approximative confidence intervals for a data set from a 31-year-old healthy right-handed, female volunteer. Moreover simulation results are presented and Monte-Carlo based quantiles, means, and variances are calculated for N in{300,600,1000}.

[The incidence of Dicrocoelium dendriticum in Emmental]

A cross-sectional field study on the prevalence of Dicrocoelium dendriticum was performed in the Emmental. The study included 211 bovines, 170 equines, 20 ovines, 46 caprines and 23 rabbits (from 119 farms). In addition, laboratory routine diagnostic data obtained from 2.840 animals--all originating from the same area of investigation--were assessed in the same way. The infection extent concerning the different animal species were the following: bovines 46%, equines 12%, ovines 30%, caprines 48% and rabbits 9%. Univariate analyses of baseline epidemiological data identified no significant risk factors, with the exception of the type of stable used. Bovines kept in a modern free ranging stable had a significantly lower chance of infection with D. dendriticum than cattle in conventional tie stalls. The epidemiological data characterizing the area of investigation suggest the following procedure to reduce the problem of dicrocoeliosis: Pasturing animals of all ages should be regularly dewormed (e.g. every six week during pasture) using a compound effective against D. dendriticum. A treatment is especially indicated at the time after pasture in autumn or before housing the animals in winter. In spring, only animals having pastured the year before need to be treated prior to pasture in the new year. However, it is recommended to perform an economic analysis comparing costs of treatment versus putative costs of damage prior to the initiation of a strategic campaign: animal welfare aspects have to be considered. The laboratory routine diagnostic data showed infection extent similar to those of the cross-sectional study: bovines 60%, equines 24%, ovines 26%, caprines 31%, rabbits 32%. Atypical hosts such as dogs and cats exhibited low infection extent (3% and 1%, respectively), rather reflecting a gastro-intestinal passage of parasite eggs ingested by consumption of infected livers or by coprophagy of ruminant faeces.

The exchange of radiotherapy data as part of an electronic patient-referral system

PURPOSE: To describe the implementation and use of an electronic patient-referral system as an aid to the efficient referral of patients to a remote and specialized treatment center. METHODS AND MATERIALS: A system for the exchange of radiotherapy data between different commercial planning systems and a specially developed planning system for proton therapy has been developed through the use of the PAPYRUS diagnostic image standard as an intermediate format. To ensure the cooperation of the different TPS manufacturers, the number of data sets defined for transfer has been restricted to the three core data sets of CT, VOIs, and three-dimensional dose distributions. As a complement to the exchange of data, network-wide application-sharing (video-conferencing) technologies have been adopted to provide methods for the interactive discussion and assessment of treatments plans with one or more partner clinics. RESULTS: Through the use of evaluation plans based on the exchanged data, referring clinics can accurately assess the advantages offered by proton therapy on a patient-by-patient basis, while the practicality or otherwise of the proposed treatments can simultaneously be assessed by the proton therapy center. Such a system, along with the interactive capabilities provided by video-conferencing methods, has been found to be an efficient solution to the problem of patient assessment and selection at a specialized treatment center, and is a necessary first step toward the full electronic integration of such centers with their remotely situated referral centers.

Bronchial circulation after experimental lung transplantation: the effect of direct revascularization of a bronchial artery

Direct revascularization of a bronchial artery has been proposed as a measure to alleviate the problem of bronchial ischemia after lung transplantation. To assess the effect of restoration of arterial blood flow to the transplanted bronchus, bronchial mucosal blood flow was measured in a model of modified unilateral lung transplantation in pigs. Laser Doppler velocimetry (LDV) and radioisotope studies using radio-labeled erythrocytes (RI) were used to measure blood flow at the donor main carina (DC) and upper lobe carina (DUC) after 3 h of reperfusion. The recipient carina was used as a reference point; values obtained by LDV and RI were expressed as percentage of blood flow at the recipient carina. Two groups of animals were studied. In group 1 (n = 6) standard unilateral transplantation was performed; in group 2 (n = 6) a left bronchial artery was reimplanted into the descending thoracic aorta of the recipient. No differences were observed between the two groups with respect to preoperative or postoperative gas exchange or hemodynamics. In group 1, bronchial blood flow at the DC was 37.6 +/- 2.2% (LDV) and 44.1 +/- 14.8% (RI) of reference blood flow. At the DUC, blood flow was 54.9 +/- 7.7% (LDV) and 61.6 +/- 25.7% (RI) of normal flow. In group 2, blood flow was increased at the DC as measured by LDV (55.3 +/- 17.1%; p less than 0.05) and by RI (60.8 +/- 25.3%; p less than 0.2). A similar increase was found at the DUC (LDV: 81.8 +/- 19.3%; p less than 0.05; RI: 88.6 +/- 31.0%; p less than 0.2). It is concluded that there is a significant gradient of blood flow from intra- to extrapulmonary airways after lung transplantation. Reimplantation of a bronchial artery results in significant improvement of graft bronchial blood flow. Restoration of bronchial perfusion to normal levels, however, cannot be achieved, suggesting a possible defect in the microcirculation of the donor airways.

Investigation on the evolution of an indoor robotic localization system based on wireless networks

This work addresses the evolution of an artificial neural network (ANN) to assist in the problem of indoor robotic localization. We investigate the design and building of an autonomous localization system based on information gathered from wireless networks (WN). The article focuses on the evolved ANN, which provides the position of a robot in a space, as in a Cartesian coordinate system, corroborating with the evolutionary robotic research area and showing its practical viability. The proposed system was tested in several experiments, evaluating not only the impact of different evolutionary computation parameters but also the role of the transfer functions on the evolution of the ANN. Results show that slight variations in the parameters lead to significant differences on the evolution process and, therefore, in the accuracy of the robot position.

Does ‘better’ discounting lead to ‘worse’ outcomes in long-run decisions? The dilemma of hyperbolic discounting

The shortcomings of conventional discounting, especially in the context of long-run environmental problems, have been extensively discussed in the literature. Recently, hyperbolic discounting, i. e. discounting at declining instead of constant discount rates, has attracted a lot of interest among both scientists and politicians. Although there are compelling arguments for employing hyperbolic discounting, there are also pitfalls, which have to be pointed out. In this paper I show that the problem of time-inconsistency, an inherent characteristics of hyperbolic discounting, leads to a potential clash between economic efficiency and intergenerational equity. As an example, I refer to the weak progress in the controlling of greenhouse gas emissions under the Kyoto protocol. As the problem of time-inconsistency cannot be solved on economic grounds alone, there is a need for an intergenerational moral commitment.

The use of unmanned aerial vehicles and wireless sensor networks for spraying pesticides

The application of pesticides and fertilizers in agricultural areas is of crucial importance for crop yields. The use of aircrafts is becoming increasingly common in carrying out this task mainly because of their speed and effectiveness in the spraying operation. However, some factors may reduce the yield, or even cause damage (e.g., crop areas not covered in the spraying process, overlapping spraying of crop areas, applying pesticides on the outer edge of the crop). Weather conditions, such as the intensity and direction of the wind while spraying, add further complexity to the problem of maintaining control. In this paper, we describe an architecture to address the problem of self-adjustment of the UAV routes when spraying chemicals in a crop field. We propose and evaluate an algorithm to adjust the UAV route to changes in wind intensity and direction. The algorithm to adapt the path runs in the UAV and its input is the feedback obtained from the wireless sensor network (WSN) deployed in the crop field. Moreover, we evaluate the impact of the number of communication messages between the UAV and the WSN. The results show that the use of the feedback information from the sensors to make adjustments to the routes could significantly reduce the waste of pesticides and fertilizers.

Malnutrition in the era of DRG

Malnutrition in hospital patients is of important medical and economic significance. The adverse consequences of malnutrition on quality of life and many more factors such as morbidity, mortality, tolerance of treatments and length of hospital stay are well documented in the medical literature. Nevertheless, the effects of malnutrition are still often underestimated and hence malnutrition is not recognised as a distinct diagnosis. Moreover, malnutrition is rarely documented in medical reports and often not adequately treated with adverse effects. The reason for this neglectfulness are diverse, e. g. inadequate training of doctors and nurses in clinical nutrition and lack of sensibilisation of the hospital staff for the problem of malnutrition. Therefore, a systematic screening for malnutrition is rarely undertaken in Swiss hospitals. The introduction of the Swiss-DRG system (DRG, diagnosis related groups) in January 2012 gave the chance to boost recording and to document malnutrition in a standardised way in the patient history, and to code precisely malnutrition as a distinct diagnosis. Moreover, this approach allowed to document the specific nutritional therapy. Here, we describe the way of documenting and coding malnutrition in the Swiss-DRG system and the medical and economic consequences of this procedure.

The Jurisprudence of the World Trade Organization 2014

In 2014, the Dispute Settlement Body (DSB) of the World Trade Organization (WTO) adopted seven panel reports and six Appellate Body rulings. Two of the cases relate to anti-dumping measures. Three cases, comprising five complaints, are of particular interest and these are summarized and discussed below. China – Rare Earths further refines the relationship between protocols of accession and the general provisions of WTO agreements, in particular the exceptions of Article XX GATT. Recourse to that provision is no longer excluded but depends on a careful case-by-case analysis. While China failed to comply with the conditions for export restrictions, the case reiterates the problem of insufficiently developed disciplines on export restrictions on strategic minerals and other commodities in WTO law. EC – Seals Products is a landmark case for two reasons. Firstly, it limits the application of the Agreement on Technical Barriers to Trade (TBT Agreement) resulting henceforth in a narrow reading of technical regulations. Normative rules prescribing conditions for importation are to be dealt with under the rules of the General Agreement on Tariffs and Trade (GATT) instead. Secondly, the ruling permits recourse to public morals in justifying import restrictions essentially on the basis of process and production methods (PPMs). Meanwhile, the more detailed implications for extraterritorial application of such rules and for the concept of PPMs remain open as these key issues were not raised by the parties to the case. Peru – Agricultural Products adds to the interpretation of the Agreement on Agriculture (AoA), but most importantly, it confirms the existing segregation of WTO law and the law of free trade agreements. The case is of particular importance for Switzerland in its relations with the European Union (EU). The case raises, but does not fully answer, the question whether in a bilateral agreement, Switzerland or the EU can, as a matter of WTO law, lawfully waive their right of lodging complaints against each other under WTO law within the scope of their bilateral agreement, for example the Agreement on Agriculture where such a clause exists.

Methodological issues in quantifying the magnitude of the tuberculosis problem in a prison population

SETTING: Correctional settings and remand prisons. OBJECTIVE: To critically discuss calculations for epidemiological indicators of the tuberculosis (TB) burden in prisons and to provide recommendations to improve study comparability. METHODS: A hypothetical data set illustrates issues in determining incidence and prevalence. The appropriate calculation of the incidence rate is presented and problems arising from cross-sectional surveys are clarifi ed. RESULTS: Cases recognized during the fi rst 3 months should be classifi ed as prevalent at entry and excluded from any incidence rate calculation. The numerator for the incidence rate includes persons detected as having developed TB during a specifi ed period of time subsequent to the initial 3 months. The denominator is persontime at risk from 3 months onward to the end point (TB or end of the observation period). Preferably, entry time, exit time and event time are known for each inmate to determine person-time at risk. Failing that, an approximation consists of the sum of monthly head counts, excluding prevalent cases and those persons no longer at risk from both the numerator and the denominator. CONCLUSIONS: The varying durations of inmate incarceration in prisons pose challenges for quantifying the magnitude of the TB problem in the inmate population. Recommendations are made to measure incidence and prevalence.