Predictability of bitcoin returns

This paper comprehensively examines the performance of a host of popular variables to predict Bitcoin returns. We show that time-series momentum, economic policy uncertainty, and financial uncertainty outperform other predictors in all in-sample, out-of-sample, and asset allocation tests. Bitcoin returns have no exposure to common stock and bond market factors but rather are affected by Bitcoin-specific and external uncertainty factors

Predictability of bitcoin returns

This paper comprehensively examines the performance of a host of popular variables to predict Bitcoin returns. We show that time-series momentum, economic policy uncertainty, and financial uncertainty outperform other predictors in all in-sample, out-of-sample, and asset allocation tests. Bitcoin returns have no exposure to common stock and bond market factors but rather are affected by Bitcoin-specific and external uncertainty factors

Commuting tillage operations of HRP under hydraulic cylinder movements on plough-breast performance

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Design of Novel S-Shaped Quad-Band Antenna for MedRadio/WMTS/ISM Implantable Biotelemetry Applications

A novel S-shaped quad-band planar inverted-F antenna (PIFA) is proposed for implantable biotelemetry in the Medical Device Radiocommunications Service (MedRadio) band (401–406 MHz), Wireless Medical Telemetry Service (WMTS) band (1427–1432 MHz), and industrial, scientific, and medical (ISM) bands (433-434 MHz and 2.4–2.4835 GHz). The proposed antenna reveals compact dimension of 254 mm3 (10×10×2.45 mm3) and is composed of three substrates and a superstrate, which are constructed from an S-shaped radiator (layer 1) and two twin radiators of spiral structures (layer 2 and layer 3). The optimal antenna characteristics were measured in the ground pork skin, and the measured bandwidths are 150 MHz for the MedRadio and ISM bands (433 MHz), 52 MHz for the WMTS band, and 102 MHz for the ISM band (2.4 GHz), respectively. The characteristics of proposed antenna are enough to support the applications of implantable body area networks (BAN) for biotelemetry and can completely cover main available frequency bands of BAN for biotelemetry below 3 GHz

(Z)-4-(2-Hy­droxy­benzyl­idene)-1-methyl-2-phenyl-1H-imidazol-5(4H)-one

In the title compound, C17H14N2O2, the asymmetric unit comprises two mol­ecules that are comformationally similar [the dihedral angles between the phenyl rings in each are 46.35 (2) and 48.04 (3)°], with the conformation stabilized by intra­molecular O—H⋯N hydrogen bonds, which generate S(7) rings. In the crystal, inversion-related mol­ecules are linked by pairs of weak C—H⋯O hydrogen bonds, forming dimers with an R 2 2(16) graph-set motif. Weak inter-ring π–π stacking is observed in the structure, the shortest centroid-to-centroid distance being 3.7480 (13) Å

Tillage condition effects on soil/plow-breast flow interaction of a horizontally reversible plow

Abstract : The horizontally reversible plow (HRP) is commonly utilized because of higher performances than the regular mold-board plow. Soil/plow surface flow interaction during HRP tillage trends to incur so severe pressure on the plow-breast as to reduce the plow life. This paper numerically characterized the soil/plow-breast flow interaction and subsequently assessed tillage-condition effects on the plow-breast surface. These tillage conditions herein involved tool speed and operation-al depth. The simulations showed that for either tool speed or operational depth the maximum pressure appeared at the plow-shank of the plow-breast and that the soil pressures were increased with them. The computational fluid dynamics (CFD) based predictions qualitatively agreed with the preliminary experimental results at the identified settings with scanning electronic microscopy. Once again, CFD analysis is demonstrated to be feasible and effective enough to provide insight into improve the horizontally reversible plow by predicting real soil behaviors

In situ reconstruction of septic aortic pseudoaneurysm due to Salmonella or Streptococcus microbial aortitis: long-term follow-up

AbstractObjectiveThis study was undertaken to illustrate the safety of in situ reconstruction of septic aortic pseudoaneurysm (SAP) secondary to microbial aortitis, with or without long-term antibiotic treatment.MethodsData for patients with SAP (11 abdominal, 4 thoracic) operated on between 1993 and 1999 were reviewed. Computed tomography and aortography showed septic pseudoaneurysm in all patients before surgery. After diagnosis of SAP, all patients underwent aneurysm resection and extensive debridement, with in situ prosthetic grafting or patch repair angioplasty. The graft in 10 of the 11 patients with abdominal SAP was also wrapped with an omental pedicle. In vitro active parenteral antibiotic therapy was prescribed for all patients for at least 2 to 8 weeks after surgery.ResultsAll 15 patients had positive preoperative blood cultures or intraoperative tissue cultures for Salmonella spp (n = 12), viridans Streptococcus (n = 1), group G Streptococcus (n = 1), or Streptococcus pneumoniae (n = 1). There were two perioperative deaths (13.3%), one 6 days after surgery and the other 19 days after surgery, and two late deaths, at 8 and 10 months after surgery, neither of which was related to aortic repair. One patient was unavailable for follow-up. The other 10 patients have been regularly followed up with abdominal ultrasound or computed tomography (mean, 84 months; range, 47-118 months). To date, there has been no graft infection, thrombosis, false aneurysm, or subsequent aortic surgery in these 10 patients.ConclusionSAP due to Salmonella and streptococcal microbial arortitis can be successfully treated with resection of the aneurysm and extensive debridement, followed by in situ prosthetic graft interposition or patch repair aortoplasty. This is a safe and effective treatment that may result in complete remission of SAP. Postoperative parenteral antibiotic therapy should be continued for 2 to 8 weeks. Although usually recommended, lifelong suppressive antibiotic therapy appears to be nonessential with this approach