ABSTRACT
Multimessenger searches for binary neutron star (BNS) and neutron star-black hole (NSBH) mergers are currently one of the most exciting areas of astronomy. The search for joint electromagnetic and neutrino counterparts to gravitational wave (GW)s has resumed with ALIGO's, AdVirgo's and KAGRA's fourth observing run (O4). To support this effort, public semiautomated data products are sent in near real-time and include localization and source properties to guide complementary observations. In preparation for O4, we have conducted a study using a simulated population of compact binaries and a mock data challenge (MDC) in the form of a real-time replay to optimize and profile the software infrastructure and scientific deliverables. End-toend performance was tested, including data ingestion, running online search pipelines, performing annotations, and issuing alerts to the astrophysics community. We present an overview of the low-latency infrastructure and the performance of the data products that are now being released during O4 based on the MDC. We report the expected median latency for the preliminary alert of full bandwidth searches (29.5 s) and show consistency and accuracy of released data products using the MDC. We report the expected median latency for triggers from early warning searches (-3.1 s), which are new in O4 and target neutron star mergers during inspiral phase. This paper provides a performance overview for LIGO-Virgo-KAGRA (LVK) low-latency alert infrastructure and data products using theMDCand serves as a useful reference for the interpretation of O4 detections.
ABSTRACT
Plantar taping has been used in clinical settings as a short-term conservative treatment for plantar heel pain and related pathologies. The rise of at-home taping methods may offer patients more independence, but effectiveness has not been established. The purpose of this study was to evaluate the effects of plantar taping on foot mechanics during gait. We hypothesized that material compliance would drive mechanical effectiveness, with longitudinally inelastic tape reducing medial longitudinal arch (MLA) motion and anterior/posterior (A/P) plantar tissue spreading forces, and laterally inelastic tape reducing medial/lateral (M/L) tissue spreading. We also hypothesized that these effects would be influenced by foot structure. Fifteen healthy participants were tested in a randomized cross-over study design. Barefoot (BF) plus four taping methods were evaluated, including two inelastic tapes (Low-Dye, LD, and FasciaDerm, FD) along with longitudinally elastic kinesiology tape (KT) and a novel laterally elastic kinesiology tape (FAST, FS). Participants' arch height and flexibility were measured followed by instrumented gait analysis with a multi-segment foot model. Ankle eversion and MLA drop/rise were calculated from rearfoot and forefoot reference frames, while plantar tissue spreading was calculated from shear stresses. ANOVAs with Holm pairwise tests evaluated tape effects while correlations connected arch structure and taping effectiveness (α = 0.05). The three longitudinally inelastic tapes (LD, FD, FS) reduced MLA drop by 11-15% compared with KT and BF. In late stance, these tapes also inhibited MLA rise (LD by 29%, FD and FS by 10-15%). FS and FD reduced A/P spreading forces, while FD reduced M/L spreading forces compared with all other conditions. Arch height had a moderately strong correlation (r = -0.67) with the difference in MLA drop between BF and FS. At-home plantar taping can affect the mechanical function of the foot, but tape elasticity direction matters. Longitudinally elastic kinesiology tape has little effect on mechanics, while inelastic tapes control MLA drop but also restrict MLA rise in late stance. Lateral elasticity does not limit tissue spreading and may increase comfort without sacrificing MLA control. At-home taping has the potential to broaden conservative treatment of plantar heel pain, flat foot deformity, and related pathologies, but additional studies are needed to connect mechanics with symptom relief.
