425 research outputs found
Impact differences among the landing phases of a drop vertical jump in soccer players
The aim of this study was to examine the differences of landing phase biomechanics between the players who had anterior cruciate ligament (ACL) reconstruction and healthy participants during single leg drop vertical jump. In this study, 11 soccer players who had anterior cruciate ligament reconstruction (aged 23.0±3.6 years, height 177±5.0 cm, weight 83.8±11.7 kg) and 9 healthy soccer players( aged 22.2±2.4 years, height 178±3.0 cm, weight 74.3±6.1 kg) participated voluntarily. During the data collection phase three high speed cameras synchronized to each other and force plate were used. Visual analysis programme and MATLAB were used to calculate kinetic and kinematic variables. Landing techniques of the subjects' were examined by flexion angle of knee, ground reaction force and moment parameters. The statistical analyses of the measured results were performed by t-test and Pearson Correlation analysis. According to the results, it was determined that peak vertical ground reaction force exhibited significant phase differences (p=0.00, and p=0.00, respectively) between the groups. Obtained results can be explained with "quadriceps avoidance" motion pattern which is characterized by decreased quadriceps activity and lower external knee flexion moment in an effort to control anterior translation of the tibia in subjects with ACL reconstruction. A better understanding of the different phases during single-leg landings can shed a light on mechanism of non-contact anterior crucaite ligament injuries therefore future researches should assess how phase differences affect drop vertical jump performance. © 2018 Montenegrin Sports Academy. All rights reserved
UnSplit: Data-Oblivious Model Inversion, Model Stealing, and Label Inference Attacks Against Split Learning
Training deep neural networks often forces users to work in a distributed or
outsourced setting, accompanied with privacy concerns. Split learning aims to
address this concern by distributing the model among a client and a server. The
scheme supposedly provides privacy, since the server cannot see the clients'
models and inputs. We show that this is not true via two novel attacks. (1) We
show that an honest-but-curious split learning server, equipped only with the
knowledge of the client neural network architecture, can recover the input
samples and obtain a functionally similar model to the client model, without
being detected. (2) We show that if the client keeps hidden only the output
layer of the model to "protect" the private labels, the honest-but-curious
server can infer the labels with perfect accuracy. We test our attacks using
various benchmark datasets and against proposed privacy-enhancing extensions to
split learning. Our results show that plaintext split learning can pose serious
risks, ranging from data (input) privacy to intellectual property (model
parameters), and provide no more than a false sense of security.Comment: Proceedings of the 21st Workshop on Privacy in the Electronic Society
(WPES '22), November 7, 2022, Los Angeles, CA, US
Trehalose loading through the mitochondrial permeability transition pore enhances desiccation tolerance in rat liver mitochondria
AbstractTrehalose has extensively been used to improve the desiccation tolerance of mammalian cells. To test whether trehalose improves desiccation tolerance of mammalian mitochondria, we introduced trehalose into the matrix of isolated rat liver mitochondria by reversibly permeabilizing the inner membrane using the mitochondrial permeability transition pore (MPTP). Measurement of the trehalose concentration inside mitochondria using high performance liquid chromatography showed that the sugar permeated rapidly into the matrix upon opening the MPTP. The concentration of intra-matrix trehalose reached 0.29 mmol/mg protein (∼190 mM) in 5 min. Mitochondria, with and without trehalose loaded into the matrix, were desiccated in a buffer containing 0.25 M trehalose by diffusive drying. After re-hydration, the inner membrane integrity was assessed by measurement of mitochondrial membrane potential with the fluorescent probe JC-1. The results showed that following drying to similar water contents, the mitochondria loaded with trehalose had significantly higher inner membrane integrity than those without trehalose loading. These findings suggest the presence of trehalose in the mitochondrial matrix affords improved desiccation tolerance to the isolated mitochondria
Temporal variations of the fractal properties of seismicity in the western part of the north Anatolian fault zone: possible artifacts due to improvements in station coverage
International audienceSeismically-active fault zones are complex natural systems exhibiting scale-invariant or fractal correlation between earthquakes in space and time, and a power-law scaling of fault length or earthquake source dimension consistent with the exponent b of the Gutenberg-Richter frequency-magnitude relation. The fractal dimension of seismicity is a measure of the degree of both the heterogeneity of the process (whether fixed or self-generated) and the clustering of seismic activity. Temporal variations of the b-value and the two-point fractal (correlation) dimension Dc have been related to the preparation process for natural earthquakes and rock fracture in the laboratory These statistical scaling properties of seismicity may therefore have the potential at least to be sensitive short- term predictors of major earthquakes. The North Anatolian Fault Zone (NAFZ) is a seismicallyactive dextral strike slip fault zone which forms the northern boundary of the westward moving Anatolian plate. It is splayed into three branches at about 31oE and continues westward toward the northern Aegean sea. In this study, we investigate the temporal variation of Dc and the Gutenberg-Richter b-value for seismicity in the western part of the NAFZ (including the northern Aegean sea) for earthquakes of Ms > 4.5 occurring in the period between 1900 and 1992. b ranges from 0.6-1.6 and Dc from 0.6 to 1.4. The b-value is found to be weakly negatively correlated with Dc (r=-0.56). However the (log of) event rate N is positively correlated with b, with a similar degree of statistical significance (r=0.42), and negatively correlated with Dc (r=-0.48). Since N increases dramatically with improved station coverage since 1970, the observed negative correlation between b and Dc is therefore more likely to be due to this effect than any underlying physical process in this case. We present this as an example of how man-made artefacts of recording can have similar statistical effects to underlying processes
SplitGuard: Detecting and Mitigating Training-Hijacking Attacks in Split Learning
Distributed deep learning frameworks, such as split learning, have recently been proposed to enable a group of participants to collaboratively train a deep neural network without sharing their raw data. Split learning in particular achieves this goal by dividing a neural network between a client and a server so that the client computes the initial set of layers, and the server computes the rest. However, this method introduces a unique attack vector for a malicious server attempting to steal the client\u27s private data: the server can direct the client model towards learning a task of its choice. With a concrete example already proposed, such training-hijacking attacks present a significant risk for the data privacy of split learning clients.
In this paper, we propose SplitGuard, a method by which a split learning client can detect whether it is being targeted by a training-hijacking attack or not. We experimentally evaluate its effectiveness, and discuss in detail various points related to its use. We conclude that SplitGuard can effectively detect training-hijacking attacks while minimizing the amount of information recovered by the adversaries
Experimental analysis of refrigerated truck thermal behaviour
Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.This study mainly focuses on experimental investigation of
ceiling-slot ventilated enclosures for determining the airflow
and thermal characteristics. The experimental prototype has the
dimensions of 8.33 m (length) x 2.50 m (height) x 2.46 m
(width) and the cooled air is injected into the container through
a half-width slot positioned at the centre of front surface and
close to the ceiling. The prototype is positioned inside of a
climatic test chamber having dimensions of 14 m (length) x 5 m
(width) x 6.5 m (height). The temperature and the relative
humidity of the test chamber may be varied within limits of (-
20°C and +50°C), and (5% and 95%) respectively. The air
velocity at the slot exit is varied by changing the fan speed so
that two different Reynolds numbers 4.3x105 and 7.86x105 are
studied in the analysis. In experiments, the system at specified
inside, outside and airflow conditions is approximately run for
two hours to establish steady-state conditions. In recording
data, the system data is divided into two groups: 1. The cooling
unit data that includes refrigerant side volumetric flow rate, the
pressure and temperature at the inlet and outlet of compressor,
condenser and evaporator. Additionally, temperature and
volumetric flow rate of air through the condenser, and the fuel
consumption of the engine are also recorded. 2. The container
data covers air velocity at the slot exit, and a total of 110
thermocouples measure the surface temperatures of all surfaces
(inside and outside) of the container and local temperature
variation of the airflow. Measurements carried out at both sides
(air side and refrigerant side) to validate the data with an
accuracy band ±6.5% of the air side measurements. The
thermal performance of ventilation in the container is measured
by a non-dimensional temperature distribution, θx at a particular
cross-section. As a result of measured data, conventional COP
of the system and f COP based on fuel consumption rate are
also presented.dc201
Evaluation of Fescue (Festuca arundinacea Schreb. and Festuca rubra L.) Populations Grown under Aegean Region Conditions
Ege Bölgesine uyumlu tür ve populasyonları belirlemek için kamışsı yumak (Festuca arundinacea Schreb.) ve kırmızı yumak (Festuca rubra L.) türlerine ait toplam 43 adet populasyon 2002 ve 2004 yılları arasında Ege Tarımsal Araştırma Enstitiüsü (ETAE) deneme tarlasında gözlemlendi. Populasyonlar 2001 yılında multipodlarda çimlendirildikten sonar 2002 yılının ilkbaharında 1m x1 m aralıkla tarlaya aktarıldı. İncelenen özellikler; kardeşlenme, ilkbahar büyüme hızı, yüzde elli başaklanma, başaklanma durumu, başaklanmada bitki gelişim özelliği, bitki boyu, biçimden sonra büyüme hızı, kuru madde ve tohum verimi olmuştur. İncelenen karakterler açısından populasyonlar arasında önemli farklılıklar gözlenmiştir. Kamışsı yumak populasyonlarından daha fazla kuru madde verimi alınmıştır. İlkbahar gelişim hızları açısından populasyonlar arası önemli farklılıklar tespit edilmiştir. Kamışsı yumak populasyonları daha yüksek ilkbahar gelişme hızı göstermişlerdir. Yüzde elli başaklanma türler ve populasyonlar arsında erkenciden geççiye kadar değişim göstermiştir. Genel olarak kırmızı yumak populasyonları daha erkenci başaklanma özelliğine ve daha yüksek başaklanma potansiyeline sahip olmuşlardır. Biçim sonrası büyüme açısından da populasyonlar arasında önemli farklılıklar bulunmuştur. Kamışsı yumak populasyonları daha yüksek büyüme potansiyeli göstermiştir. Kamışsı ve kırmızı yumak türlerinin bu çalışma ile Ege Bölgesinde farklı amaçlar için kullanılabileceği tesbit edilmiştir.A total of 43 materials of tall fescue (Festuca arundinacea Schreb.) and red fescue (Festuca rubra L.) were examined at experimental fields of Aegean Agricultural Research Institute (AARI) in the years of 2002 and 2004 in order to determine adaptation of species, populations and high yielding cultivars adapting to Aegean region. Populations were sown in multipods in 2001 and transferred to field with 1x1 m spacing in the spring of 2002. Characteristics observed were tillering, spring growth rate, time of 50 % inflorescence, abundance of inflorence, vegetative growth habit at inflorence, plant height, growth rate after cutting, dry matter yield and seed yield. Significant differences were observed between populations in terms of characters investigated. Dry matter yield was higher in tall fescue. There were significant differences between the populations in terms of spring growth. Tall fescue populations had higher spring growth rates. Flowering time of 50 % inflorescence of species and populations varied from early to late. In general, populations of red fescue had early 50% inflorescence time and also higher potential for abundance of inflorence. Significant differences were also found between populations in terms of their growth rate after cutting. Tall fescue populations showed higher growth potential. It was found that tall fescue and red fescue could be used with various purposes at Aegean Region
Les ressources génétiques forestières dans le bassin méditerranéen
Ce texte est le rapport du Groupe FAO d'experts des ressources génétiques forestières, pour la Méditerranée. Il a été présenté par Michel Bariteau, membre de ce groupe, lors de la 12e Session de la FAO à Rome, du 21 au 23 novembre 2001. Il fait le point sur l'état actuel des ressources génétiques forestières dans l'ensemble des pays du bassin méditerranéen
Spring cleaning as a safety risk: results of a population-based study in two consecutive years
<p>Abstract</p> <p>Background</p> <p>Spring cleaning is a popular tradition in Iran as well as in many other countries. The purpose of our study was to determine the pattern and compare the incidence of spring cleaning related injuries in Tehran, in the years 2007 and 2008.</p> <p>Methods</p> <p>In the year 2007, a household survey was performed in Tehran by random cluster sampling. The survey was repeated in May 2008 with the same clusters and starting points, but different households. The incidence of spring cleaning related injuries, the age and sex of injured person(s), the mechanism, type and cost of injuries were recorded through semi-structured interviews. The incidence rates of injuries and injuries leading to health visits (severe) according to sex and age groups were calculated. Data were analyzed using SPSS and STATA statistical softwares.</p> <p>Results</p> <p>The incidence of all and severe spring cleaning related injuries were 3.8 (3.0 - 4.8) and 1.6 (1.1-2.3) per 1000, respectively. The most common mechanisms of injuries were falls, followed by cutting and lifting heavy objects or overexertion. Falls were also the main mechanism of severe injuries. The most common injuries were open wounds, followed by superficial injuries (including contusions) and sprain and strain. Among severe injuries, the most frequent injuries were open wounds and contusions, followed by dislocations. The injuries were most common among women with an incidence of about 8.4 per 1000 in women older than 18 years of age (severe injuries: 3.4 per 1000 (2.2-5.1)).</p> <p>Conclusion</p> <p>The incidence of spring cleaning related injuries is high enough to raise concern in health system authorities. It could be estimated that about 23,927 to 38,283 persons get injured during the spring cleaning in Tehran at the beginning of every Persian new year. In addition, about 8,773-18,344 of these cases are expected to be severe enough to lead to medical attention (considering 7,975,679 as the population of Tehran at the time of study). Improving awareness of families, especially young women, regarding the scope and importance of spring cleaning safety can be suggested as the first population-based strategy to decrease the incidence of these injuries.</p
- …