Creophilus maxillosus (L., 1758) is a common and widely distributed beetle species found on corpses, and its development duration is far longer than species belonging to the genus Calliphoridae and ...Sarcophagidae. Therefore, C. maxillosus can be used as a supplementary indicator to estimate minimum postmortem interval (PMImin), and could greatly extend the range of PMImin when the primary colonizers are no longer associated with the corpse or have emerged from pupae. Better descriptions of C. maxillosus development are needed to apply this species for forensic investigations. In this study, the development of C. maxillosus at seven constant temperatures ranging from 17.5–32.5 °C was studied. Through regression analyses, the simulation equations of larval body length variation with time after hatching were obtained. Isomegalen diagrams of the changes of larval body length over time at specific temperatures, and the isomorphen diagrams on the duration of different developmental milestones at specific temperatures were generated. In addition, thermal summation models of different developmental stages and the overall development process of C. maxillosus were generated through regression analysis, by estimating the development threshold temperatures (D0) and the thermal summation constants (K). These results provide important tools for forensic investigations to generate a long-range of PMImin estimation based on the development of C. maxillosus.
The quantum entangled J/ψ→Σ^{+}Σover ¯^{-} pairs from (1.0087±0.0044)×10^{10} J/ψ events taken by the BESIII detector are used to study the nonleptonic two-body weak decays Σ^{+}→nπ^{+} and Σover ...¯^{-}→nover ¯π^{-}. The CP-odd weak decay parameters of the decays Σ^{+}→nπ^{+} (α_{+}) and Σover ¯^{-}→nover ¯π^{-} (αover ¯_{-}) are determined to be 0.0481±0.0031_{stat}±0.0019_{syst} and -0.0565±0.0047_{stat}±0.0022_{syst}, respectively. The decay parameter αover ¯_{-} is measured for the first time, and the accuracy of α_{+} is improved by a factor of 4 compared to the previous results. The simultaneously determined decay parameters allow the first precision CP symmetry test for any hyperon decay with a neutron in the final state with the measurement of A_{CP}=(α_{+}+αover ¯_{-})/(α_{+}-αover ¯_{-})=-0.080±0.052_{stat}±0.028_{syst}. Assuming CP conservation, the average decay parameter is determined as ⟨α_{+}⟩=(α_{+}-αover ¯_{-})/2=-0.0506±0.0026_{stat}±0.0019_{syst}, while the ratios α_{+}/α_{0} and αover ¯_{-}/αover ¯_{0} are -0.0490±0.0032_{stat}±0.0021_{syst} and -0.0571±0.0053_{stat}±0.0032_{syst}, where α_{0} and αover ¯_{0} are the decay parameters of the decays Σ^{+}→pπ^{0} and Σover ¯^{-}→pover ¯π^{0}, respectively.
Abstract
Pulsating ultraluminous X-ray sources (PULXs) are accreting pulsars with apparent X-ray luminosity exceeding 10
39
erg s
−1
. We perform Monte Carlo simulations to investigate whether a high ...collimation effect (or strong beaming effect) is dominant in the presence of accretion outflows, for the fan beam emission of the accretion column of the neutron stars in PULXs. We show that the three nearby PULXs (RX J0209.6−7427, Swift J0243.6+6124, and SMC X-3), namely, the Three Musketeers here, have their main pulsed emission not strongly collimated even if strong outflows exist. This conclusion can be extended to the current sample of extragalactic PULXs, if accretion outflows are commonly produced from them. This means that the observed high luminosity of PULXs is indeed intrinsic, which can be used to infer the existence of very strong surface magnetic fields of ∼10
13–14
G, possibly multipole fields. However, if strong outflows are launched from the accretion disks in PULXs as a consequence of disk spherization by radiation pressure, regular dipole magnetic fields of ∼10
12
G may be required, comparable to that of the Three Musketeers, which have experienced large luminosity changes from well below their Eddington limit (2 × 10
38
erg s
−1
for an NS) to super-Eddington and whose maximum luminosity fills the luminosity gap between Galactic pulsars and extragalactic PULXs.
The oxidation in 1 atm O2 of two Co-20Ni-yAl (y = 3,5 wt%), two Co-20Ni-xCr (x = 8,15 wt%) and a Co-20Ni alloy was studied at 800–900 °C. Except for Co-20Ni-15Cr oxidized at 900 °C, all the ternary ...alloys oxidized more rapidly than the binary alloy Co-20Ni at both temperatures. A thin protective oxide layer formed only on the surface of the ternary alloy Co-20Ni-15Cr by oxidation at 900 °C. In all the other cases the scales contained an outer layer of Co-Ni oxide plus an inner layer of Co-Ni oxide mixed with spinels and a zone of internal oxidation.
•All Co-20Ni-R alloys, except Co-20Ni-15Cr at 900 °C, oxidize more rapidly than the binary Co-20Ni alloy at both temperatures.•All ternary alloys, except Co-20Ni-15Cr at 900 °C, form duplex external scales of Co-Ni oxides and spinels plus IOZ.•15 wt.% Cr in the Co-20Ni-Cr alloys is sufficient to form protective external chromia scales by oxidation at 900 °C.•Ni is beneficial for the oxidation of ternary Co-20Ni-based alloys compared to the corresponding Ni-free binary Co-base alloys.
Context.
A link has finally been established between magnetars and fast radio burst (FRB) sources. Within this context, a major issue that remains unresolved pertains to whether sources of ...extragalactic FRBs exhibit X/
γ
-ray outbursts and whether this is correlated with radio activity. If so, the subsequent goal is to identify these sources.
Aims.
We aim to constrain possible X/
γ
-ray burst activity from one of the nearest extragalactic FRB sources currently known. This is to be done over a broad energy range by looking for bursts over a range of timescales and energies that are compatible with those of powerful flares from extragalactic magnetars.
Methods.
We followed up on the observation of the as-yet nearest extragalactic FRB source, located at a mere 149 Mpc distance, namely, the periodic repeater
FRB 180916.J0158+65
. This took place during the active phase between 4 and 7 February 2020, using the Insight–Hard X-ray Modulation Telescope (Insight–HXMT). By taking advantage of the combination of broad-band wavelengths, a large effective area, and several independent detectors at our disposal, we searched for bursts over a set of timescales from 1 ms to 1.024 s with a sensitive algorithm that had been previously characterised and optimised. Moreover, through simulations, we studied the sensitivity of our technique in the released energy-duration phase space for a set of synthetic flares and assuming a range of different energy spectra.
Results.
We constrain the possible occurrence of flares in the 1−100 keV energy band to
E
< 10
46
erg for durations Δ
t
< 0.1 s over several tens of ks exposure.
Conclusions.
We can rule out the occurrence of giant flares similar to the ones that were observed in the few cases of Galactic magnetars. The absence of reported radio activity during our observations prevents us from making any determinations regarding the possibility of simultaneous high-energy emission.
To define the equivalent cut-off values of Bath ankylosing Spondylitis Disease Activity Index (BASDAI) for discriminating disease activity corresponding to Ankylosing Spondylitis Disease Activity ...Score (ASDAS) cut-off values, and to determine the equivalent change units for determining the clinically improvement between ΔBASDAI and ΔASDAS-CRP.
475 patients with axial spondyloarthritis (axSpA) whose data on BASDAI and ASDAS were available were included. Among them, 154 (32.4%) patients whose data on ΔBASDAI and ΔASDAS-CRP were available. Receiver-operator curve (ROC) with area under curve (AUC) was used to determine the BASDAI cut-off values that best corresponded to ASDAS-CRP. The Cohen's kappa was utilised to assess the degree of agreement between disease activity states based on BASDAI and ASDAS cut-off values, and clinically improvement between ΔBASDAI and ΔASDAS-CRP.
According to the ASDAS-CRP, 88 (18.6%), 130 (27.4%), 191 (40.1%) and 66 (13.9%) patients were classified as inactive, moderate, high and very high disease activities, respectively. ROC revealed that BASDAI values 1.6 (AUC: 0.948), 2.9 (AUC: 0.790) and 3.8 (AUC: 0.875) best corresponded to ASDAS-CRP values 1.3, 2.1 and 3.5, respectively. The degree of agreement between them was moderate (kappa: 0.527). The ΔBASDAI 1.6 (AUC: 0.745) and 2.0 (AUC: 0.708) best corresponded to the ΔASDAS-CRP 1.1 (minimal clinically important improvement) and 2.0 (major improvement), respectively. The degree of agreement was good (kappa: 0.685).
The BASDAI values 1.6, 2.9 and 3.8 correspond to ASDAS-CRP values 1.3, 2.1 and 3.5, respectively. The ΔBASDAI 1.6 and 2.0 best correspond to the ΔASDAS-CRP 1.1 and 2.0, respectively.
ABSTRACT
RX J0440.9+4431, a Be/X-ray binary, had its brightest outburst in 2022 since its discovery, with a peak X-ray flux of 2.25 Crab (as recorded by Swift/BAT, 15–50 keV). We analyze the timing ...properties of this giant outburst using data from Insight-Hard X-ray Modulation Telescope and Neutron Star Interior Composition Exlporer, focusing on the evolution of the pulse profile and pulse fraction. We observe that when the luminosity reached around ~$3\times 10^{37}\ {\rm erg\ \rm s^{-1}}$, a transition from double-peaked to single-peaked pulse profiles occurred across the energy range, with the peak of the low-energy profile aligning gradually with the peak of the high-energy profile. This change indicates a transition from subcritical to supercritical accretion. Additionally, we found a concave in the pulse fraction as a function of energy around 20–30 keV throughout the entire outburst period. Compared to the low luminosity, the concave becomes weaker in high luminosities, and overall, the pulse fraction is higher. We propose that this concave could be caused by the scattering of high-energy photons by the atmosphere of a neutron star, leading to a dilution of the pulse fraction. As the accretion reaches the supercritical state, the accretion column height increases, resulting in a larger direct component of strongly beamed X-ray flux, and an elevated pulse fraction.
In this paper, 3-D numerical simulations were performed for laminar heat transfer and fluid flow characteristics of wavy fin-and-tube heat exchanger by body-fitted coordinates system. The effect of ...four factors were examined:
Reynolds number, fin pitch, wavy angle and tube row number. The Reynolds number based on the tube diameter varied from 500 to 5000, the fin pitch from 0.4 to 5.2
mm, the wavy angle from 0° to 50°, and the tube row range from 1 to 4. The numerical results were compared with experiments and good agreement was obtained. The numerical results show that with the increasing of wavy angles, decreasing of the fin pitch and tube row number, the heat transfer of the finned tube bank are enhanced with some penalty in pressure drop. The effects of the four factors were also analyzed from the view point of field synergy principle which says that the reduction of the intersection angle between velocity and fluid temperature gradient is the basic mechanism for enhance convective heat transfer. It is found that the effects of the four factors on the heat transfer performance of the wavy fin-and-tube exchangers can be well described by the field synergy principle.
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