Adaptive point cloud acquisition and upsampling for automotive lidar.

One of the crucial factors in achieving a higher level of autonomy of self-driving vehicles is a sensor capable of acquiring accurate and robust information about the environment and other participants in traffic. In the past few decades, various types of sensors have been used for this purpose, such as cameras registering visible, near-infrared, and thermal parts of the spectrum, as well as radars, ultrasonic sensors, and lidar. Due to their high range, accuracy, and robustness, lidars are gaining popularity in numerous applications. However, in many cases, their spatial resolution does not meet the requirements of the application. To solve this problem, we propose a strategy for better utilization of the available points. In particular, we propose an adaptive paradigm that scans the objects of interest with increased resolution, while the background is scanned using a lower point density. Initial region proposals are generated using an object detector that relies on an auxiliary camera. Such a strategy improves the quality of the representation of the object, while retaining the total number of projected points. The proposed method shows improvements compared to regular sampling in terms of the quality of upsampled point clouds.

Identifying a Neuromedin U Receptor 2 Splice Variant and Determining Its Roles in the Regulation of Signaling and Tumorigenesis In Vitro.

Neuromedin U (NMU) activates two G protein-coupled receptors, NMUR1 and NMUR2; this signaling not only controls many physiological responses but also promotes tumorigenesis in diverse tissues. We recently identified a novel truncated NMUR2 derived by alternative splicing, namely NMUR2S, from human ovarian cancer cDNA. Sequence analysis, cell surface ELISA and immunocytochemical staining using 293T cells indicated that NMUR2S can be expressed well on the cell surface as a six-transmembrane protein. Receptor pull-down and fluorescent resonance energy transfer assays demonstrated that NMUR1, NMUR2 and this newly discovered NMUR2S can not only form homomeric complexes but also heteromeric complexes with each other. Although not activated by NMU itself, functional assay in combination with receptor quantification and radio-ligand binding in 293T cells indicated that NMUR2S does not alter the translocation and stability of NMUR1 or NMUR2, but rather effectively dampens their signaling by blocking their NMU binding capability through receptor heterodimerization. We further demonstrated that NMU signaling is significantly up-regulated in human ovarian cancers, whereas expression of NMUR2S can block endogenous NMU signaling and further lead to suppression of proliferation in SKOV-3 ovarian cancer cells. In contrast, in monocytic THP-1 cells that express comparable levels of NMUR1 and NMUR2S, depletion of NMUR2S restored both the signaling and effect of NMU. Thus, these results not only reveal the presence of previously uncharacterized heteromeric relationships among NMU receptors but also provide NMUR2S as a potential therapeutic target for the future treatment of NMU signaling-mediated cancers.

Ovarian regulation of neuromedin U and its local actions in the ovary, mediated through neuromedin U receptor 2.

Neuromedin U (NMU) was originally identified as an anorexigenic peptide that modulates appetite as well as energy homeostasis through the brain-gut axis. Although growing evidence has linked NMU activity with the development of female reproductive organs, no direct expression of and function for NMU in these organs has been pinpointed. Using a superovulated rat model, we found that NMU is directly expressed in the ovary, where its transcript level is tightly regulated by gonadotropins. Ovarian microdissection and immunohistochemical staining showed clearly that NMU is expressed mainly in theca/interstitial cells and to a moderate extent in granulosa cells. Primary cell studies together with reporter assays indicated the Nmu mRNA level in these cells is strongly induced via cAMP signaling, whereas this increase in expression can be reversed by the degradation message residing within its 3'-untranslated region, which recruits cis-acting mRNA degradation mechanisms, such as the gonadotropin-induced zinc finger RNA-binding protein Zfp36l1. This study also demonstrated that NMUR2, but not NMUR1, is the dominant NMU receptor in the ovary, where its expression is restricted to theca/interstitial cells. Treatment with NMU led to induction of the early response c-Fos gene, phosphorylation of extracellular signal-regulated kinase 1/2, and promotion of progesterone production in both developing and mature theca/interstitial cells. Taken as a whole, this study demonstrates that NMU and NMU receptor 2 compose a novel autocrine system in theca/interstitial cells in which the intensity of signaling is tightly controlled by gonadotropins.

CXCL17, an orphan chemokine, acts as a novel angiogenic and anti-inflammatory factor.

Chemokines play pivotal roles in the recruitment of various immune cells to diverse tissues in both physiological and pathological conditions. CXCL17 is an orphan chemokine preliminarily found to be involved in tumor angiogenesis. However, its protein nature, as well as its endogenous bioactivity, has not been well clarified. Using real-time PCR, immunohistochemical staining, and Western blotting, we found that CXCL17 is highly expressed in both a constitutive and inducible manner in the rat gastric mucosa, where it undergoes endoproteolysis during protein maturation. The mature CXCL17 exhibited strong chemoattractant abilities targeting monocytes and macrophages, potentially through ERK1/2 and p38 but not JNK signaling. CXCL17 also induced the production of proangiogenic factors such as vascular endothelial growth factor A from treated monocytes. Furthermore, in contrast to other CXC chemokines that accelerate inflammatory responses, CXCL17 showed novel anti-inflammatory effects on LPS-activated macrophages. Therefore, our data suggest that CXCL17 in the gastric lamina propria may play an important role in tissue repair and anti-inflammation, both of which help to maintain the integrity of the gastric mucosa.

50 fs soliton compression of optical clock pulse recovered from NRZ data injected SOAFL.

Mode-locking of semiconductor optical amplifier fiber laser (SOAFL) with 50 fs pulses by extracting the clock of an optical non-return-to-zero (NRZ) data injection is demonstrated. The efficiency of mode-locking in the SOAFL is improved by increasing the seeding power of the large-duty-cycle NRZ data from 3 to 8 dBm into the SOA driven at biased current of 350 mA. After linear dispersion compensation, the mode-locked SOAFL pulsewidth can be further shortened from 20 to 3 ps by increasing the DCF length up to 110 m. By using a booster the EDFA to enlarge the average power of mode-locked SOAFL pulse to 1.3 W, the shortest soliton pulse is occurred after propagating through a 12-m-long SMF. The amplified SOAFL pulse can be compressed to 50 fs after nonlinear compression with its spectral linewidth broadening to 64 nm. Nearly transform-limited time-bandwidth product of 0.436 and the maximum pulse compressing ratio of 400 are reported to date.