TZC: Efficient Inter-Process Communication for Robotics Middleware with Partial Serialization

Inter-process communication (IPC) is one of the core functions of modern robotics middleware. We propose an efficient IPC technique called TZC (Towards Zero-Copy). As a core component of TZC, we design a novel algorithm called partial serialization. Our formulation can generate messages that can be divided into two parts. During message transmission, one part is transmitted through a socket and the other part uses shared memory. The part within shared memory is never copied or serialized during its lifetime. We have integrated TZC with ROS and ROS2 and find that TZC can be easily combined with current open-source platforms. By using TZC, the overhead of IPC remains constant when the message size grows. In particular, when the message size is 4MB (less than the size of a full HD image), TZC can reduce the overhead of ROS IPC from tens of milliseconds to hundreds of microseconds and can reduce the overhead of ROS2 IPC from hundreds of milliseconds to less than 1 millisecond. We also demonstrate the benefits of TZC by integrating with TurtleBot2 that are used in autonomous driving scenarios. We show that by using TZC, the braking distance can be shortened by 16% than ROS

DCNS: Automated Detection of Conservative Non-Sleep Defects in the Linux Kernel

International audienceFor waiting, the Linux kernel offers both sleep-able and non-sleep operations. However, only non-sleep operations can be used in atomic context. Detecting the possibility of execution in atomic context requires a complete inter-procedural flow analysis, often involving function pointers. Developers may thus conservatively use non-sleep operations even outside of atomic context, which may damage system performance, as such operations unproductively monopolize the CPU. Until now, no systematic approach has been proposed to detect such conservative non-sleep (CNS) defects. In this paper, we propose a practical static approach, named DCNS, to automatically detect conservative non-sleep defects in the Linux kernel. DCNS uses a summary-based analysis to effectively identify the code in atomic context and a novel file-connection-based alias analysis to correctly identify the set of functions referenced by a function pointer. We evaluate DCNS on Linux 4.16, and in total find 1629 defects. We manually check 943 defects whose call paths are not so difficult to follow, and find that 890 are real. We have randomly selected 300 of the real defects and sent them to kernel developers, and 251 have been confirmed

A Genetic Basis for Mechanosensory Traits in Humans

Hearing and touch are genetically related, and people with excellent hearing are more likely to have a fine sense of touch and vice versa

Mitochondrial Function and Dysfunction in Dilated Cardiomyopathy

Cardiac tissue requires a persistent production of energy in order to exert its pumping function. Therefore, the maintenance of this function relies on mitochondria that represent the "powerhouse" of all cardiac activities. Mitochondria being one of the key players for the proper functioning of the mammalian heart suggests continual regulation and organization. Mitochondria adapt to cellular energy demands via fusion-fission events and, as a proof-reading ability, undergo mitophagy in cases of abnormalities. Ca2+ fluxes play a pivotal role in regulating all mitochondrial functions, including ATP production, metabolism, oxidative stress balance and apoptosis. Communication between mitochondria and others organelles, especially the sarcoplasmic reticulum is required for optimal function. Consequently, abnormal mitochondrial activity results in decreased energy production leading to pathological conditions. In this review, we will describe how mitochondrial function or dysfunction impacts cardiac activities and the development of dilated cardiomyopathy

The kallikrein–kinin system in diabetic nephropathy

Diabetic nephropathy is the major cause of end-stage renal disease worldwide. Although the renin-angiotensin system has been implicated in the pathogenesis of diabetic nephropathy, angiotensin I-converting enzyme (ACE) inhibitors have a beneficial effect on diabetic nephropathy independently of their effects on blood pressure and plasma angiotensin II levels. This suggests that the kallikrein-kinin system (KKS) is also involved in the disease. To study the role of the KKS in diabetic nephropathy, mice lacking either the bradykinin B1 receptor (B1R) or the bradykinin B2 receptor (B2R) have been commonly used. However, because absence of either receptor causes enhanced expression of the other, it is difficult to determine the precise functions of each receptor. This difficulty has recently been overcome by comparing mice lacking both receptors with mice lacking each receptor. Deletion of both B1R and B2R reduces nitric oxide (NO) production and aggravates renal diabetic phenotypes, relevant to either lack of B1R or B2R, demonstrating that both B1R and B2R exert protective effects on diabetic nephropathy presumably via NO. Here, we review previous epidemiological and experimental studies, and discuss novel insights regarding the therapeutic implications of the importance of the KKS in averting diabetic nephropathy

Large meta-analysis of genome-wide association studies identifies five loci for lean body mass

Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 x 10(-8)) or suggestively genome wide (p < 2.3 x 10(-6)). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/ near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/ near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass

Pterocymbium R. Br (Sterculioideae, Malvaceae), a genus new to China and suggestions for conservation

The genus Pterocymbium R. Br. is new to China, and the remarkable discovery is reported in the present study. P. macranthum Kosterm., a winged-boot tree published in 1962, has recently been spotted in the border regions of China and Laos. The main detailed anatomical characteristics of the flower are photographed, and supplementary descriptions of the species are made based on fresh materials, herbarium collections, and available literature. Historically, the tree is only recorded in Southcentral Myanmar to Northern and Southwestern Thailand. The new record in the present study extends the known geographical range of P. macranthum to the northern edge of the Asian tropics and contributes to the knowledge of the tree flora both in China and Southeast Asia. Aided by drones, the population size of China has been rapidly assessed, and ca. 1000 individuals were recognized from high-resolution photos in ca. 2000 ha area. Herbaria were prepared and deposited in the herbarium of Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences (HITBC)