1,641 research outputs found
The Economics of a Centralized Judiciary: Uniformity, Forum Shopping and the Federal Circuit
In 1982, the US Congress established the Court of Appeals for the Federal Circuit (CAFC) as the sole appellate court for patent cases. Ostensibly, this court was created to eliminate inconsistencies in the application and interpretation of patent law across federal courts, and thereby mitigate the incentives of patentees and alleged infringers to "forum shop" for a preferred venue. We perform the first econometric study of the extent of non-uniformity and forum shopping in the pre-CAFC era and of the CAFC's impact on these phenomena. We find that in patentee-plaintiff cases the pre-CAFC era was indeed characterized by significant non-uniformity in patent validity rates across circuits and by forum shopping on the basis of validity rates. We find weak evidence that the CAFC has increased uniformity of validity rates and strong evidence that forum shopping on the basis of validity rates ceased several years prior to the CAFC's establishment. In patentee-defendant cases, we find that validity rates are lower on average, but do not find either significant non-uniformity of validity rates across circuits or significant forum shopping.
Biochar: an improver of nutrient and soil water availability - what is the evidence?
Biochar has consistently been proposed as a way of improving soil fertility by increasing nutrient and soil water availability. This review critically investigates recent literature, focussing particularly on these agronomic aspects of biochar. We clarify the differences between biochar made from plant (plant derived biochar, PDB) and animal feedstock (animal derived biochar, ADB) and show how pyrolysis temperature affects biochar properties. We also tabulate crop yield data against production variables using recent field and greenhouse studies. We find evidence to suggest that ADB supplies many more nutrients than PDB and that, in general, biochar can improve nutrient availability indirectly through changes in pH, CEC, soil structure, improved fertiliser efficiency, decreased nutrient leaching and may effect nutrient availability by changing nitrogenous gas release and by changing the soil microbial community, which under some circumstances translates into short term, increased crop yield. Few studies however show complete nutrient, especially N budgets and elaborate on the underlying mechanisms of interaction, especially with regards to microbial induced changes. Also the longevity of the different beneficial effects is questionable as most studies are less than a year long. A synopsis of the literature concludes that biochar application promotes soil water availability, particularly in soils which are degraded or of low quality. Despite this conclusion it is hard to find studies that have adopted methodologies which are fully appropriate to support this notion such as available water capacity and how this changes in response to crop uptake and soil drying. We conclude that the variability in biochar due to variable feedstock and pyrolysis process, as well as particle size and application method, necessitates and also enables production of specific purposeādriven biochars to benefit particular aspects of crop production
The Strong Maximum Circulation Algorithm: A New Method for Aggregating Preference Rankings
We present a new optimization-based method for aggregating preferences in
settings where each decision maker, or voter, expresses preferences over pairs
of alternatives. The challenge is to come up with a ranking that agrees as much
as possible with the votes cast in cases when some of the votes conflict. Only
a collection of votes that contains no cycles is non-conflicting and can induce
a partial order over alternatives. Our approach is motivated by the observation
that a collection of votes that form a cycle can be treated as ties. The method
is then to remove unions of cycles of votes, or circulations, from the vote
graph and determine aggregate preferences from the remainder.
We introduce the strong maximum circulation which is formed by a union of
cycles, the removal of which guarantees a unique outcome in terms of the
induced partial order. Furthermore, it contains all the aggregate preferences
remaining following the elimination of any maximum circulation. In contrast,
the well-known, optimization-based, Kemeny method has non-unique output and can
return multiple, conflicting rankings for the same input. In addition, Kemeny's
method requires solving an NP-hard problem, whereas our algorithm is efficient,
based on network flow techniques, and runs in strongly polynomial time,
independent of the number of votes.
We address the construction of a ranking from the partial order and show that
rankings based on a convex relaxation of Kemeny's model are consistent with our
partial order. We then study the properties of removing a maximal circulation
versus a maximum circulation and establish that, while maximal circulations
will in general identify a larger number of aggregate preferences, the partial
orders induced by the removal of different maximal circulations are not unique
and may be conflicting. Moreover, finding a minimum maximal circulation is an
NP-hard problem.Comment: 22 pages, 4 figure
An investigation of minimisation criteria
Minimisation can be used within treatment trials to ensure that prognostic factors are evenly distributed between treatment groups. The technique is relatively straightforward to apply but does require running tallies of patient recruitments to be made and some simple calculations to be performed prior to each allocation. As computing facilities have become more widely available, minimisation has become a more feasible option for many. Although the technique has increased in popularity, the mode of application is often poorly reported and the choice of input parameters not justified in any logical way
Symptoms of anxiety and depression in school-aged children with active epilepsy: A population-based study
Children (5-15 years) with active epilepsy were screened using the parent-report (n=69) and self-report (n=48) versions of the Spence Children's Anxiety Scale (SCAS) and the self-report version of the Children's Depression Inventory (CDI) (n=48) in a population-based sample. A total of 32.2% of children (self-report) and 15.2% of children (parent-report) scored ā„1 SD above the mean on the SCAS total score. The subscales where most difficulty were reported on parent-report were Physical Injury and Separation Anxiety. There was less variation on self-report. On the CDI, 20.9% of young people scored ā„1 SD above the mean. Children reported significantly more symptoms of anxiety on the SCAS total score and three of the subscales (p<.05). There was a significant effect on the SCAS total score of respondents by seizure type interaction, suggesting higher scores on SCAS for children with generalized seizures on self- but not parent-report. Higher CDI scores were significantly associated with generalized seizures (p>.05).Symptoms of anxiety were more common based on self-report compared with parent-report. Children with generalized seizures reported more symptoms of depression and anxiety
Child and parental sleep in young children with epilepsy: A population-based case-control study
Objective:
To determine the prevalence of parentāreported sleep problems in young children with epilepsy and their parents, and to compare findings with those in a nonāepilepsyārelated neurodisability (neurodevelopmental/neurological difficulties) group.
Method:
Parents of young children (1ā7 years) with epilepsy (n = 48 [91% ascertainment]) completed the Child Sleep Habits Questionnaire (CSHQ). Parents (mothers and fathers) also completed the Pittsburgh Sleep Quality Index (PSQI) and the Iowa Fatigue Scale (IFS) in relation to their own functioning. The responses of parents of children with epilepsy were compared with parents of developmentalā, ageā, and genderāmatched children with nonepilepsyārelated neurodisability (n = 48).
Results:
There was not a significant difference in the proportion of children with epilepsy and the children with neurodisability scoring in the atārisk range on the CSHQ (81% vs. 71% respectively) (p = 0.232). 62% of mothers and 44% of fathers of children with epilepsy had āpoor quality sleepā on the PSQI; there was not a significant difference between mothers of children with epilepsy and those of children with neurodisability (p = 0.526) or IFS (p = 0.245) total scores. However, mothers of children with epilepsy had significantly more difficulties on the productivity subscale of the IFS (p = 0.004). There were no significant differences between fathersā scores on either measure. In the epilepsy group, child behavioral problems (p = 0.001) were independently associated with child sleep difficulties and maternal mental health problems were associated with parental sleep difficulties (p = 0.04) and fatigue (p = 0.018).
Significance:
Young children with epilepsy and their parents have a high rate of sleep difficulties. There is a need to develop effective interventions for this population, taking into consideration of the role of child behavioral problems and parental mental health difficulties
Workshop on Environmental Research Needs in Support of Potential Virginia Offshore Oil and Gas Activities
The MMS, a bureau within the Department of the Interior, sponsored a workshop on the environmental research needs in support of potential Virginia offshore oil and gas activities 3 and 4 December 2008, in Williamsburg, Virginia. The focus of the workshop was to assess the existing scientific knowledgebase along the Virginia Coast and the information gaps that need to 2 be addressed should a lease sale for oil and gas activities be held for the Virginia outer continental shelf. This report summarizes the outcome of the workshop
The UK Environmental Change Network datasets ā integrated and co-located data for long-term environmental research (1993ā2015)
Long-term datasets of integrated environmental variables, co-located together, are relatively rare. The UK Environmental Change Network (ECN) was launched in 1992 and provides the UK with its only long-term integrated environmental monitoring and research network for the assessment of the causes and consequences of environmental change. Measurements, covering a wide range of physical, chemical, and biological ādriverā and āresponseā variables are made in close proximity at ECN terrestrial sites using protocols incorporating standard quality control procedures. This paper describes the datasets (there are 19 published ECN datasets) for these co-located measurements, containing over 20 years of data (1993ā2015). The data and supporting documentation are freely available from the NERC Environmental Information Data Centre under the terms of the Open Government Licence (see paper for DOIs)
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