Experimental ship motion and load measurements in head and beam seas

This contribution looks at experimental ship motion and load measurements in head and beam sea

Assessing normative cut points through differential item functioning analysis: An example from the adaptation of the Middlesex Elderly Assessment of Mental State (MEAMS) for use as a cognitive screening test in Turkey

BACKGROUND: The Middlesex Elderly Assessment of Mental State (MEAMS) was developed as a screening test to detect cognitive impairment in the elderly. It includes 12 subtests, each having a 'pass score'. A series of tasks were undertaken to adapt the measure for use in the adult population in Turkey and to determine the validity of existing cut points for passing subtests, given the wide range of educational level in the Turkish population. This study focuses on identifying and validating the scoring system of the MEAMS for Turkish adult population. METHODS: After the translation procedure, 350 normal subjects and 158 acquired brain injury patients were assessed by the Turkish version of MEAMS. Initially, appropriate pass scores for the normal population were determined through ANOVA post-hoc tests according to age, gender and education. Rasch analysis was then used to test the internal construct validity of the scale and the validity of the cut points for pass scores on the pooled data by using Differential Item Functioning (DIF) analysis within the framework of the Rasch model. RESULTS: Data with the initially modified pass scores were analyzed. DIF was found for certain subtests by age and education, but not for gender. Following this, pass scores were further adjusted and data re-fitted to the model. All subtests were found to fit the Rasch model (mean item fit 0.184, SD 0.319; person fit -0.224, SD 0.557) and DIF was then found to be absent. Thus the final pass scores for all subtests were determined. CONCLUSION: The MEAMS offers a valid assessment of cognitive state for the adult Turkish population, and the revised cut points accommodate for age and education. Further studies are required to ascertain the validity in different diagnostic groups

Equality of averaged and quenched large deviations for random walks in random environments in dimensions four and higher

We consider large deviations for nearest-neighbor random walk in a uniformly elliptic i.i.d. environment. It is easy to see that the quenched and the averaged rate functions are not identically equal. When the dimension is at least four and Sznitman's transience condition (T) is satisfied, we prove that these rate functions are finite and equal on a closed set whose interior contains every nonzero velocity at which the rate functions vanish.Comment: 17 pages. Minor revision. In particular, note the change in the title of the paper. To appear in Probability Theory and Related Fields

What to expect from the hydrodynamic energy saving devices

Many retrofitting technologies have been proposed to improve the hydrodynamic performance of existing fleets with the aim of reducing the fuel consumption and consequently CO2 emission. The magnitudes of savings predicted by manufacturers are very promising however ship owners are often still doubtful whether they can achieve what is claimed in operations. This study evaluates the performance of four energy saving devices (ESDs) at ship scale with the aim of assisting ship owners with the decision of selecting suitable devices for their ships. Due to the uncertainties associated with extrapolation of viscous flows from model to full scale it is proposed that investigations must be carried out at full scale; hence a full-scale com putational model was adopted as the only feasible method at the design stage. Two vessels representing di fferent types of ship were selected: a gas carrier and a container ship. Various retrofitting technologies to reduce resistance or to improve the propulsive efficiency were considered. The latter group is subdivided into devices located before, at and aft of the propeller. The resistance induced by large openings on the hull, such as a bow thruster tunnel was quantified and several devices designed to streamline the flow in this region were evaluated. Pre-swirl fins technology was the ESD investigated from preswirl devices. The existing propeller of the gas carrier was replaced with a new type profile propeller which improved the propulsive efficiency. Twisted rudder was the technology investigated from post-swirl ESDs. The level of savings obtained from these technologies was generally less than the values published in the literature. It was concluded that this discrepancy arose for one of three reasons: either the metric used to evaluate the savings was inappropriate, or that the method used to quantify the measure was in accurate, or finally, because the designs examined in the case studies were not suitable optimised. However if some of these devices did not deliver the expected savings because the designs considered in this study were not sufficiently optimised, then the question arises as to whether these devices must be optimised for a specific operational conditions and how well these ESDs behave when the vessel is not operating in the design conditions

Revision of the Upper Cretaceous ammonite fauna of the Bakony Mountains (Hungary)

A revision of the ammonites from the Bakony Mountains (Hungaty) based on collections of the Geological Institute of Hungary (MAFI) in Budapest, revealed the following sequence of faunas. The youngest Campanian ammonites from the South Bakony are three specimens ofPachydiscus (P.)praecolligatus COLLIGNON, 1955 from the Siimeg area; this is a typical Campanian species. Two specimens of former "Lower Maastrichtian Pachydiscus neubergicus (HAUER)" from Haraszt quany have been re-determined as Early Campanian Eupachydiscus levyi (GROSS OUVRE, 1894). The fragmentary specimen of Mortoniceras sp. has been determined as Texanites (Texanites) sp. from the Upper Santonian. Two ammonite zones can be recognised for these sequences: Texanites sp. (Santonian) and Eupachydiscus levyi (Lower Campanian)

Worth the wait: effects of age of onset of marijuana use on white matter and impulsivity

Rationale: Marijuana (MJ) use continues to rise, and as the perceived risk of using MJ approaches an all-time historic low, initiation of MJ use is occurring at even younger ages. As adolescence is a critical period of neuromaturation, teens and emerging adults are at greater risk for experiencing the negative effects of MJ on the brain. In particular, MJ use has been shown to be associated with alterations in frontal white matter microstructure, which may be related to reports of increased levels of impulsivity in this population. Objectives: The aim of this study was to examine the relationship between age of onset of MJ use, white matter microstructure, and reported impulsivity in chronic, heavy MJ smokers. Methods: Twenty-five MJ smokers and 18 healthy controls underwent diffusion tensor imaging and completed the Barratt Impulsiveness Scale. MJ smokers were also divided into early onset (regular use prior to age 16) and late onset (age 16 or later) groups in order to clarify the impact of age of onset of MJ use on these variables. Results: MJ smokers exhibited significantly reduced fractional anisotropy (FA) relative to controls, as well as higher levels of impulsivity. Earlier MJ onset was also associated with lower levels of FA. Interestingly, within the early onset group, higher impulsivity scores were correlated with lower FA, a relationship that was not observed in the late onset smokers. Conclusions: MJ use is associated with white matter development and reported impulsivity, particularly in early onset smokers

Creation and implementation of an emergency medicine education and training program in Turkey: An effective educational intervention to address the practitioner gap

Background The specialty of Emergency Medicine has enjoyed recognition for nearly 20 years in Turkey. However, the majority of underserved and rural Turkish emergency departments are staffed by general practitioners who lack formal training in the specialty and have few opportunities to increase emergency medicine-specific knowledge and skills. Methods To address this “practitioner gap,” the authors developed a four-phase comprehensive emergency medicine education and training program for general practitioners practicing in government hospitals in Turkey. Results From April 2006 until June 2009, 42 courses were taught by 62 trainers across seven regions in Turkey. A total of 2,262 physicians were trained. The mean course pre-test score for all regions was 42.3 (95% CI 39.8 to 44.7). The mean course post-test score was 70.1 (95% CI 67.2 to 72.9). The difference between the mean scores was 27.8 (95% CI 25.3 to 30.4, P \u3c0.0001), reflecting an improvement of 65.7%. Conclusions A partnership between an academic emergency medicine department and an emergency medicine society to implement country-wide training of physicians practicing in public emergency departments can serve as a successful model for capacity-building global emergency medicine endeavors

A Note on Projective Klingenberg Planes over Rings of Plural Numbers

This paper deals with a certain class of projective Klingenberg planes over the local ring F[eta]/lteta^{m}gt with F an arbitrary field, known as the plural algebra of order m. In particular addition and multiplication of points on a line is defined geometrically and interpreted algebraically, by using the coordinate ring

Yönlendirmeli Filtreler Yardımıyla Konya Bölgesi Civarındaki Gömülü Fayların Tespiti

In this paper, steerable filters are used in the evaluation of geophysical data. Steerable filters are band-pass filters having direction property. In extraction of directional properties, input data is passed through various directed band pass filters and then grouped into sub-bands. Here, to present the performance of steerable filters, we have chosen synthetic examples having various direction properties and tried to find out the borders of these samples. As a field study, we have used gravity anomaly map of Konya region. The anomalies caused by buried faults are evaluated for different angles and obtained fault map of the region is compared to previous geological results.Bu makalede, yönlendirmeli filtreler jeofizik verilerin değerlendirilmesinde kullanılmışlardır. Yönlendirmeli filtreler belirli bir doğrultuda band geçiren filtrelerdir. Yönlendirmeli filtreler de, giriş görüntüsündeki farklı yönlerdeki kenarların elde edilmesi için, görüntü ilk önce farklı yönlere sahip temel filtrelerden geçirilir ve daha sonra yönelim alt-bandlarına ayrılır. Bu çalışmada, yönlendirmeli filtrelerin başarımını görebilmek için, çeşitli açılara sahip sentetik datalar ele alınmış ve kenar belirlemesi yapılmıştır. Arazi çalışması olarak, Konya bölgesinin gravite anomali haritasını kullandık. Gömülü durumda bulunan fayların oluşturduğu anomaliler farklı yönler için incelenmiş ve bölgenin oluşturulan fay haritası jeolojik bilgilerle karşılaştırılmıştır