Reducing congestion in obstructed highways with traffic data dissemination using adhoc vehicular networks

Vehicle-to-vehicle communications can be used effectively for intelligent transport systems (ITSs) and location-aware services. The ability to disseminate information in an ad hoc fashion allows pertinent information to propagate faster through a network. In the realm of ITS, the ability to spread warning information faster and further is of great advantage to receivers. In this paper we propose and present a message-dissemination procedure that uses vehicular wireless protocols to influence vehicular flow, reducing congestion in road networks. The computational experiments we present show how a car-following model and lane-change algorithm can be adapted to “react” to the reception of information. This model also illustrates the advantages of coupling together with vehicular flow modelling tools and network simulation tools

Neutral organic radical formation by chemisorption on metal surfaces

Organic radical monolayers (r-MLs) bonded to metal surfaces are potential materials for the development of molecular (spin)electronics. Typically, stable radicals bearing surface anchoring groups are used to generate r-MLs. Following a recent theoretical proposal based on a model system, we report the first experimental realization of a metal surface-induced r-ML, where a rationally chosen closed-shell precursor 3,5-dichloro-4-[bis(2,4,6-trichlorophenyl)methylen]cyclohexa-2,5-dien-1-one (1) transforms into a stable neutral open-shell species () via chemisorption on the Ag(111) surface. X-ray photoelectron spectroscopy reveals that the >C=O group of 1 reacts with the surface, forming a C-O-Ag linkage that induces an electronic rearrangement that transforms 1 to . We further show that surface reactivity is an important factor in this process whereby Au(111) is inert towards 1, whereas the Cu(111) surface leads to dehalogenation reactions. The radical nature of the Ag(111)-bound monolayer was further confirmed by angle-resolved photoelectron spectroscopy and electronic structure calculations, which provide evidence of the emergence of the singly occupied molecular orbital (SOMO) of 1

Radial Photonic Crystal for detection of frequency and position of radiation sources

Based on the concepts of artificially microstructured materials, i.e. metamaterials, we present here the first practical realization of a radial wave crystal. This type of device was introduced as a theoretical proposal in the field of acoustics, and can be briefly defined as a structured medium with radial symmetry, where the constitutive parameters are invariant under radial geometrical translations. Our practical demonstration is realized in the electromagnetic microwave spectrum, because of the equivalence between the wave problems in both fields. A device has been designed, fabricated and experimentally characterized. It is able to perform beam shaping of punctual wave sources, and also to sense position and frequency of external radiators. Owing to the flexibility offered by the design concept, other possible applications are discussed.This work was supported in part by the Spanish Ministry of Science and Innovation under Grants TEC 2010-19751 and CSD2008-00066 (Consolider program) and by the U.S. Office of Naval Research under Grant N000140910554.Carbonell Olivares, J.; Díaz Rubio, A.; Torrent Martí, D.; Cervera Moreno, FS.; Kirleis, MA.; Pique, A.; Sánchez-Dehesa Moreno-Cid, J. (2012). Radial Photonic Crystal for detection of frequency and position of radiation sources. Scientific Reports. 2(558):1-8. https://doi.org/10.1038/srep00558S182558Pendry, J., Schurig, D. & Smith, D. Controlling electromagnetic fields. Science 312, 1780–1782 (2006).Leonhardt, U. Optical conformal mapping. Science 312, 1777–1780 (2006).Smith, D., Padilla, W., Vier, D., Nemat-Nasser, S. & Schultz, S. Composite medium with simultaneously negative permeability and permittivity. Phys. Rev. Lett. 84, 4184–4187 (2000).Pendry, J. B. Negative refraction makes a perfect lens. Phys. Rev. Lett. 85, 3966–3969 (2000).Schurig, D. et al. Metamaterial electromagnetic cloak at microwave frequencies. Science 314, 977–980 (2006).Narimanov, E. E. & Kildishev, A. V. Optical black hole: Broadband omnidirectional light absorber. Appl. Phys. Lett. 95, 041106 (2009).Grbic, A. & Eleftheriades, G. Overcoming the diffraction limit with a planar left-handed transmission-line lens. Phys. Rev. Lett. 92, 117403 (2004).Ma, H. F. & Cui, T. J. Three-dimensional broadband ground-plane cloak made of metamaterials. Nature Communications 1, 21 (2010).Engheta, N., Salandrino, A. & Alu, A. Circuit elements at optical frequencies: Nanoinductors, nanocapacitors and nanoresistors. Phys. Rev. Lett. 95, 095504 (2005).Zhang, F. et al. Negative-Zero-Positive Refractive Index in a Prism-Like Omega-Type Metamaterial. IEEE Trans. Microwave Theory Tech. 56, 2566–2573 (2008).Baena, J., Marques, R., Medina, F. & Martel, J. Artificial magnetic metamaterial design by using spiral resonators. Phys. Rev. B 69, 014402 (2004).Carbonell, J., Torrent, D., Diaz-Rubio, A. & Sanchez-Dehesa, J. Multidisciplinary approach to cylindrical anisotropic metamaterials. New J. Phys. 13, 103034 (2011).Torrent, D. & Sanchez-Dehesa, J. Radial Wave Crystals: Radially Periodic Structures from Anisotropic Metamaterials for Engineering Acoustic or Electromagnetic Waves. Phys. Rev. Lett. 103, 064301 (2009).Torrent, D. & Sanchez-Dehesa, J. Acoustic resonances in two-dimensional radial sonic crystal shells. New J. Phys. 12, 073034 (2010).Kurs, A. et al. Wireless power transfer via strongly coupled magnetic resonances. Science 317, 83–86 (2007).Marques, R., Medina, F. & Rafii-El-Idrissi, R. Role of bianisotropy in negative permeability and left-handed metamaterials. Phys. Rev. B 65, 144440 (2002).Pendry, J. B., Holden, A. J., Robbins, D. J. & Stewart, W. J. Magnetism from conductors and enhanced nonlinear phenomena. IEEE Trans. Microwave Theory Tech. 47, 2075–2084 (1999).Pollock, J. G. & Iyer, A. K. Effective-Medium Properties of Cylindrical Transmission-Line Metamaterials. IEEE Antennas and Wireless Propagation Letters 10, 1491–1494 (2011).Comsol, A. B. (Sweden). Comsol Multiphysics (v. 4.1). (2010).Ansoft. High Frequency Structure Simulator (HFSS), v.14. (2012).Smith, D. R., Vier, D. C., Koschny, T. & Soukoulis, C. M. Electromagnetic parameter retrieval from inhomogeneous metamaterials. Phys. Rev. E 71, 036617 (2005).Yang, Y. et al. Optofluidic waveguide as a transformation optics device for lightwave bending and manipulation. Nature Communications 3, 651 (2012).Liu, R. et al. Broadband Ground-Plane Cloak. Science 323, 366–369 (2009).Cheng, Q., Cui, T. J., Jiang, W. X. & Cai, B. G. An omnidirectional electromagnetic absorber made of metamaterials. New J. Phys. 12, 063006 (2010)

Transparent Gradient-Index Lens for Underwater Sound Based on Phase Advance

Spatial gradients in a refractive index are used extensively in acoustic metamaterial applications to control wave propagation through phase delay. This study reports the design and experimental realization of an acoustic gradient-index lens using a sonic crystal lattice that is impedance matched to water over a broad bandwidth. In contrast to previous designs, the underlying lattice features refractive indices that are lower than the water background, which facilitates propagation control based on a phase advance as opposed to a delay. The index gradient is achieved by varying the filling fraction of hollow, air-filled aluminum tubes that individually exhibit a higher sound speed than water and matched impedance. Acoustic focusing is observed over a broad bandwidth of frequencies in the homogenization limit of the lattice, with intensity magnifications in excess of 7 dB. An anisotropic lattice design facilitates a flat-faceted geometry with low backscattering at 18 dB below the incident sound-pressure level. A three-dimensional Rayleigh-Sommerfeld integration that accounts for the anisotropic refraction is used to accurately predict the experimentally measured focal patterns.This work is supported by the Office of Naval Research.Martin, TP.; Naify, C.; Skerritt, E.; Layman, C.; Nicholas, M.; Calvo, D.; Orris, GJ.... (2015). Transparent Gradient-Index Lens for Underwater Sound Based on Phase Advance. Physical Review Applied. 4(3):034003-1-034003-8. doi:10.1103/PhysRevApplied.4.034003S034003-1034003-843Naify, C. J., Martin, T. P., Layman, C. N., Nicholas, M., Thangawng, A. L., Calvo, D. C., & Orris, G. J. (2014). Underwater acoustic omnidirectional absorber. Applied Physics Letters, 104(7), 073505. doi:10.1063/1.4865480Li, R.-Q., Zhu, X.-F., Liang, B., Li, Y., Zou, X.-Y., & Cheng, J.-C. (2011). A broadband acoustic omnidirectional absorber comprising positive-index materials. Applied Physics Letters, 99(19), 193507. doi:10.1063/1.3659690Climente, A., Torrent, D., & Sánchez-Dehesa, J. (2012). Omnidirectional broadband acoustic absorber based on metamaterials. Applied Physics Letters, 100(14), 144103. doi:10.1063/1.3701611Martin, T. P., Layman, C. N., Moore, K. M., & Orris, G. J. (2012). Elastic shells with high-contrast material properties as acoustic metamaterial components. Physical Review B, 85(16). doi:10.1103/physrevb.85.161103Titovich, A. S., & Norris, A. N. (2014). Tunable cylindrical shell as an element in acoustic metamaterial. The Journal of the Acoustical Society of America, 136(4), 1601-1609. doi:10.1121/1.4894723Zhang, B., Chan, T., & Wu, B.-I. (2010). Lateral Shift Makes a Ground-Plane Cloak Detectable. Physical Review Letters, 104(23). doi:10.1103/physrevlett.104.233903Yin, M., Yong Tian, X., Xue Han, H., & Chen Li, D. (2012). Free-space carpet-cloak based on gradient index photonic crystals in metamaterial regime. Applied Physics Letters, 100(12), 124101. doi:10.1063/1.3696040Torrent, D., & Sánchez-Dehesa, J. (2007). Acoustic metamaterials for new two-dimensional sonic devices. New Journal of Physics, 9(9), 323-323. doi:10.1088/1367-2630/9/9/323Climente, A., Torrent, D., & Sánchez-Dehesa, J. (2010). Sound focusing by gradient index sonic lenses. Applied Physics Letters, 97(10), 104103. doi:10.1063/1.3488349Martin, T. P., Nicholas, M., Orris, G. J., Cai, L.-W., Torrent, D., & Sánchez-Dehesa, J. (2010). Sonic gradient index lens for aqueous applications. Applied Physics Letters, 97(11), 113503. doi:10.1063/1.3489373Peng, S., He, Z., Jia, H., Zhang, A., Qiu, C., Ke, M., & Liu, Z. (2010). Acoustic far-field focusing effect for two-dimensional graded negative refractive-index sonic crystals. Applied Physics Letters, 96(26), 263502. doi:10.1063/1.3457447Sanchis, L., Yánez, A., Galindo, P. L., Pizarro, J., & Pastor, J. M. (2010). Three-dimensional acoustic lenses with axial symmetry. Applied Physics Letters, 97(5), 054103. doi:10.1063/1.3474616Zigoneanu, L., Popa, B.-I., & Cummer, S. A. (2011). Design and measurements of a broadband two-dimensional acoustic lens. Physical Review B, 84(2). doi:10.1103/physrevb.84.024305Lin, S.-C. S., Tittmann, B. R., & Huang, T. J. (2012). Design of acoustic beam aperture modifier using gradient-index phononic crystals. Journal of Applied Physics, 111(12), 123510. doi:10.1063/1.4729803Chang, T. M., Dupont, G., Enoch, S., & Guenneau, S. (2012). Enhanced control of light and sound trajectories with three-dimensional gradient index lenses. New Journal of Physics, 14(3), 035011. doi:10.1088/1367-2630/14/3/035011Hladky-Hennion, A.-C., Vasseur, J. O., Haw, G., Croënne, C., Haumesser, L., & Norris, A. N. (2013). Negative refraction of acoustic waves using a foam-like metallic structure. Applied Physics Letters, 102(14), 144103. doi:10.1063/1.4801642Ren, C., Xiang, Z., & Cen, Z. (2010). Design of acoustic devices with isotropic material via conformal transformation. Applied Physics Letters, 97(4), 044101. doi:10.1063/1.3467852Layman, C. N., Martin, T. P., Moore, K. M., Calvo, D. C., & Orris, G. J. (2011). Designing acoustic transformation devices using fluid homogenization of an elastic substructure. Applied Physics Letters, 99(16), 163503. doi:10.1063/1.3652914Maldovan, M. (2013). Sound and heat revolutions in phononics. Nature, 503(7475), 209-217. doi:10.1038/nature12608Kadic, M., Bückmann, T., Schittny, R., & Wegener, M. (2013). Metamaterials beyond electromagnetism. Reports on Progress in Physics, 76(12), 126501. doi:10.1088/0034-4885/76/12/126501Torrent, D., & Sánchez-Dehesa, J. (2008). Anisotropic mass density by two-dimensional acoustic metamaterials. New Journal of Physics, 10(2), 023004. doi:10.1088/1367-2630/10/2/023004Parazzoli, C. G., Koltenbah, B. E. C., Greegor, R. B., Lam, T. A., & Tanielian, M. H. (2006). Eikonal equation for a general anisotropic or chiral medium: application to a negative-graded index-of-refraction lens with an anisotropic material. Journal of the Optical Society of America B, 23(3), 439. doi:10.1364/josab.23.000439Ward, G. P., Lovelock, R. K., Murray, A. R. J., Hibbins, A. P., Sambles, J. R., & Smith, J. D. (2015). Boundary-Layer Effects on Acoustic Transmission Through Narrow Slit Cavities. Physical Review Letters, 115(4). doi:10.1103/physrevlett.115.044302Guild, M. D., García-Chocano, V. M., Kan, W., & Sánchez-Dehesa, J. (2015). Acoustic metamaterial absorbers based on multilayered sonic crystals. Journal of Applied Physics, 117(11), 114902. doi:10.1063/1.4915346Reyes-Ayona, E., Torrent, D., & Sánchez-Dehesa, J. (2012). Homogenization theory for periodic distributions of elastic cylinders embedded in a viscous fluid. The Journal of the Acoustical Society of America, 132(4), 2896-2908. doi:10.1121/1.4744933Molerón, M., Serra-Garcia, M., & Daraio, C. (2014). Acoustic Fresnel lenses with extraordinary transmission. Applied Physics Letters, 105(11), 114109. doi:10.1063/1.4896276Li, Y., Yu, G., Liang, B., Zou, X., Li, G., Cheng, S., & Cheng, J. (2014). Three-dimensional Ultrathin Planar Lenses by Acoustic Metamaterials. Scientific Reports, 4(1). doi:10.1038/srep06830Gao, Y., Liu, J., Zhang, X., Wang, Y., Song, Y., Liu, S., & Zhang, Y. (2012). Analysis of focal-shift effect in planar metallic nanoslit lenses. Optics Express, 20(2), 1320. doi:10.1364/oe.20.001320Born, M., Wolf, E., Bhatia, A. B., Clemmow, P. C., Gabor, D., Stokes, A. R., … Wilcock, W. L. (1999). Principles of Optics. doi:10.1017/cbo9781139644181Shen, C., Xu, J., Fang, N. X., & Jing, Y. (2014). Anisotropic Complementary Acoustic Metamaterial for Canceling out Aberrating Layers. Physical Review X, 4(4). doi:10.1103/physrevx.4.041033Dubois, M., Farhat, M., Bossy, E., Enoch, S., Guenneau, S., & Sebbah, P. (2013). Flat lens for pulse focusing of elastic waves in thin plates. Applied Physics Letters, 103(7), 071915. doi:10.1063/1.4818716Dubois, M., Bossy, E., Enoch, S., Guenneau, S., Lerosey, G., & Sebbah, P. (2015). Time-Driven Superoscillations with Negative Refraction. Physical Review Letters, 114(1). doi:10.1103/physrevlett.114.013902Kock, W. E., & Harvey, F. K. (1949). Refracting Sound Waves. The Journal of the Acoustical Society of America, 21(5), 471-481. doi:10.1121/1.1906536Liang, Z., & Li, J. (2012). Extreme Acoustic Metamaterial by Coiling Up Space. Physical Review Letters, 108(11). doi:10.1103/physrevlett.108.114301Xie, Y., Konneker, A., Popa, B.-I., & Cummer, S. A. (2013). Tapered labyrinthine acoustic metamaterials for broadband impedance matching. 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Lesion Index Titration Using Contact-Force Technology Enables Safe and Effective Radiofrequency Lesion Creation at the Root of the Aorta and Pulmonary Artery

BACKGROUND: Ablation of some myocardial substrates requires catheter-based radiofrequency delivery at the root of a great artery. We studied the safety and efficacy parameters associated with catheter-based radiofrequency delivery at the root of the aorta and pulmonary artery. METHODS: Thirty-six pigs underwent in-vivo catheter-based ablation under continuous contact-force and lesion index (power, contact-force, and time) monitoring during 60-s radiofrequency delivery with an open-irrigated tip catheter. Twenty-eight animals were allocated to groups receiving 40 W (n=9), 50 W (n=10), or 60 W (n=9) radiofrequency energy, and acute (n=22) and chronic (n=6) arterial wall damage was quantified by multiphoton microscopy in ex vivo samples. Adjacent myocardial lesions were quantified in parallel samples. The remaining 8 pigs were used to validate safety and efficacy parameters. RESULTS: Acute collagen and elastin alterations were significantly associated with radiofrequency power, although chronic assessment revealed vascular wall recovery in lesions without steam pop. The main parameters associated with steam pops were median peak temperature >42°C and impedance falls >23 ohms. Unlike other parameters, lesion index values of 9.1 units (interquartile range, 8.7-9.8) were associated with the presence of adjacent myocardial lesions in both univariate ( P=0.03) and multivariate analyses ( P=0.049; odds ratio, 1.99; 95% CI, 1.02-3.98). In the validation group, lesion index values using 40 W over a range of contact-forces correlated with the size of radiofrequency lesions (R2=0.57; P=0.03), with no angiographic or histopathologic signs of coronary artery damage. CONCLUSIONS: Lesion index values obtained during 40 W radiofrequency applications reliably monitor safe and effective lesion creation at the root of the great arteries.This study was supported by the Fundación Interhospitalaria para la Investigación Cardiovascular (FIC) and the Heart Rhythm Section of the Spanish Society of Cardiology. The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Ministry of Science, Innovation and Universities and the Pro CNIC Foundation. The CNIC is a Severo Ochoa Center of Excellence (SEV-2015- 0505). This study was supported by grants from Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish Ministry of Science, Innovation and Universities (SAF2016-80324-R).S

Beaconing Approaches in Vehicular Ad Hoc Networks: A Survey

A Vehicular Ad hoc Network (VANET) is a type of wireless ad hoc network that facilitates ubiquitous connectivity between vehicles in the absence of fixed infrastructure. Beaconing approaches is an important research challenge in high mobility vehicular networks with enabling safety applications. In this article, we perform a survey and a comparative study of state-of-the-art adaptive beaconing approaches in VANET, that explores the main advantages and drawbacks behind their design. The survey part of the paper presents a review of existing adaptive beaconing approaches such as adaptive beacon transmission power, beacon rate adaptation, contention window size adjustment and Hybrid adaptation beaconing techniques. The comparative study of the paper compares the representatives of adaptive beaconing approaches in terms of their objective of study, summary of their study, the utilized simulator and the type of vehicular scenario. Finally, we discussed the open issues and research directions related to VANET adaptive beaconing approaches.Ghafoor, KZ.; Lloret, J.; Abu Bakar, K.; Sadiq, AS.; Ben Mussa, SA. (2013). Beaconing Approaches in Vehicular Ad Hoc Networks: A Survey. Wireless Personal Communications. 73(3):885-912. doi:10.1007/s11277-013-1222-9S885912733ITS-Standards (1996) Intelligent transportation systems, U.S. Department of Transportation, http://www.standards.its.dot.gov/about.aspCheng, L., Henty, B., Stancil, D., Bai, F., & Mudalige, P. (2005). Mobile vehicle-to-vehicle narrow-band channel measurement and characterization of the 5.9 Ghz dedicated short range communication (DSRC) frequency band. IEEE Transactions on Selected Areas in Communications, 25(8), 1501–1516.van Eenennaam, E., Wolterink, K., Karagiannis, G., & Heijenk, G. (2009). Exploring the solution space of beaconing in vanets. In Proceedings of the 2009 IEEE international vehicular networking conference, Tokyo (pp. 1–8).Torrent-Moreno, M. 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IEEE Network, 24(1), 14–19.Ghafoor, K., Bakar, K., van Eenennaam, E., Khokhar, R., Gonzalez, A. A fuzzy logic approach to beaconing for vehicular ad hoc networks, Accepted for publication in Telecommunication Systems Journal.Ghafoor, K., & Bakar, K. (2010). A novel delay and reliability aware inter vehicle routing protocol. Network Protocols and Algorithms, 2(2), 66–88.Mittag, J., Thomas, F., Härri, J., & Hartenstein, H. (2009). A comparison of single-and multi-hop beaconing in vanets. In Proceedings of the 2009 ACM international workshop on vehicular internetworking, Beijing (pp. 69–78).Sommer, C., Tonguz, O., & Dressler, F. (2010). Adaptive beaconing for delay-sensitive and congestion-aware traffic information systems. In Proceedings of the 2010 IEEE international vehicular networking conference (VNC), New Jersey (pp. 1–8).Guan, X., Sengupta, R., Krishnan, H., & Bai, F. (2007). A feedback-based power control algorithm design for vanet. 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Opposite cannabis-cognition associations in psychotic patients depending on family history

The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis

Accuracy and Survival Outcomes after National Implementation of Sentinel Lymph Node Biopsy in Early Stage Endometrial Cancer

Background. Sentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease. Patients and Methods. A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics. Results. A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC. Conclusions. In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC

Advances in Vehicular Ad-hoc Networks (VANETs): challenges and road-map for future development

Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of vehicular ad-hoc networks (VANETs) over the past few years. A vehicular network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of intelligent transportation system (ITS). Hence, governments, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well as the ways forward to achieving the long awaited ITS

Chemotherapy or allogeneic transplantation in high-risk Philadelphia chromosome–negative adult lymphoblastic leukemia

The need for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in adults with Philadelphia chromosome–negative (Ph−) acute lymphoblastic leukemia (ALL) with high-risk (HR) features and adequate measurable residual disease (MRD) clearance remains unclear. The aim of the ALL-HR-11 trial was to evaluate the outcomes of HR Ph− adult ALL patients following chemotherapy or allo-HSCT administered based on end-induction and consolidation MRD levels. Patients aged 15 to 60 years with HR-ALL in complete response (CR) and MRD levels (centrally assessed by 8-color flow cytometry) <0.1% after induction and <0.01% after early consolidation were assigned to receive delayed consolidation and maintenance therapy up to 2 years in CR. The remaining patients were allocated to allo-HSCT. CR was attained in 315/348 patients (91%), with MRD <0.1% after induction in 220/289 patients (76%). By intention-to-treat, 218 patients were assigned to chemotherapy and 106 to allo-HSCT. The 5-year (±95% confidence interval) cumulative incidence of relapse (CIR), overall survival (OS), and event-free survival probabilities for the whole series were 43% ± 7%, 49% ± 7%, and 40% ± 6%, respectively, with CIR and OS rates of 45% ± 8% and 59% ± 9% for patients assigned to chemotherapy and of 40% ± 12% and 38% ± 11% for those assigned to allo-HSCT, respectively. Our results show that avoiding allo-HSCT does not hamper the outcomes of HR Ph− adult ALL patients up to 60 years with adequate MRD response after induction and consolidation. Better postremission alternative therapies are especially needed for patients with poor MRD clearance