分类： 其他 提交时间： 2024-06-13
摘要： 本文总结了1例丹毒患者的中西医结合治疗临床护理经验，常规抗生素(首选青霉素)治疗，同时给予中药塌渍的中医特色技术治疗及护理干预措施，7—10 d后治愈。中西医结合治疗下肢丹毒见效快，配合护理干预有助于促进患者早日康复，减少复发风险。
分类： 其他 分类： 其他 提交时间： 2024-06-11
摘要： 本文总结了1例耳穴贴压联合穴位贴敷治疗急性阑尾炎术后肠胀气患者的护理经验。本案例通过给予腹腔镜阑尾切除术后肠胀气患者耳穴贴压联合穴位贴敷治疗的干预措施，有效改善了患者胀气的症状。
分类： 地球科学 >> 空间物理学 分类： 其他 提交时间： 2024-06-08
摘要： 469219 Kamo`oalewa is selected as one of the primary targets of Tianwen-2 mission, which is currently believed to be the most stable quasi-satellite of Earth. Here we derive a weak detection of the Yarkovsky effect for Kamo`oalewa, giving $A_2 = -1.075 pm0.447 times 10^{-13} rm{au/d}^2$, with the available ground-based optical observations from Minor Planet Center and a relatively conservative weighting scheme. Due to the quasi-satellite resonance with Earth, we show that the detection of Yarkovsky effect by orbital fitting with astrometric observations becomes difficult as its orbital drift shows a slow oscillatory growth resulting from the Yarkovsky effect. In addition, we extensively explore the characteristics of orbital uncertainty propagation and find that the positional uncertainty mainly arises from the geocentric radial direction in 2010-2020, and then concentrates in the heliocentric transverse direction in 2020-2030. Furthermore, the heliocentric transverse uncertainty is clearly monthly dependent, which can arrive at a minimum around January and a maximum around July as the orbit moves towards the leading and trailing edges, respectively, in 2025-2027. Finally, we investigate a long-term uncertainty propagation in the quasi-satellite regime, implying that the quasi-satellite resonance with Earth may play a crucial role in constraining the increase of uncertainty over time. Such interesting feature further implies that the orbital precision of Kamo`oalewa is relatively stable at its quasi-satellite phase, which may also be true for other quasi-satellites of Earth.
分类： 地球科学 >> 空间物理学 分类： 其他 分类： 其他 分类： 其他 提交时间： 2024-06-03
摘要： The Closeby Habitable Exoplanet Survey (CHES) is dedicated to the astrometric exploration for habitable-zone Earth-like planets orbiting solar-type stars in close proximity, achieving unprecedented micro-arcsecond precision. Given the elevated precision, thorough consideration of photocenter jitters induced by stellar activity becomes imperative. This study endeavors to model the stellar activity of solar-type stars, compute astrometric noise, and delineate the detection limits of habitable planets within the astrometric domain. Simulations were conducted for identified primary targets of CHES, involving the generation of simulated observed data for astrometry and photometry, accounting for the impact of stellar activity. Estimation of activity levels in our samples was achieved through chromospheric activity indices, revealing that over 90% of stars exhibited photocenter jitters below 1 $ mu mathrm{as}$. Notably, certain proximate stars, such as $ alpha$ Cen A and B, displayed more discernible noise arising from stellar activity. Subsequent tests were performed to evaluate detection performance, unveiling that stellar activity tends to have a less pronounced impact on planetary detectability for the majority of stars. Approximately 95% of targets demonstrated a detection efficiency exceeding 80%. However, for several cold stars, e.g., HD 32450 and HD 21531, with the habitable zones close to the stars, a reduction in detection efficiency was observed. These findings offer invaluable insights into the intricate interplay between stellar activity and astrometric precision, significantly advancing our understanding in the search for habitable planets.
分类： 其他 提交时间： 2024-05-10
摘要： 核素空气比释动能率常数Γa是评估剂量和屏蔽计算中非常重要的数据，Γa的计算需要用到通量到空气比释动能率的转换系数Ka/Φ以及核素衰变光子信息。2020年国际辐射与测量委员会ICRU发布了95号报告，该报告推荐了新的Ka/Φ。为了验证基础数据更新后核素 数值的变化，基于理论和蒙特卡洛方法对医学、工业、农业中常用的39种核素空气比释动能率常数进行了计算，并对不同插值方法及阈值选取做了对比分析。得到以下结论：三次样条、对数-对数拉格朗日插值、线性-对数拉格朗日插值插值方法对Γa的计算影响较小；阈值选取对Γa的计算非常重要，部分核素在不同阈值情况下计算差异较大，推荐核医学剂量估算建议使用10 keV阈值，其他情况阈值选取20 keV；理论计算和MCNP模拟计算差异较小，都可用于常数的计算。
分类： 其他 提交时间： 2024-05-07
摘要： 互补型金属氧化物半导体（Complementary Metal Oxide Semiconductor, CMOS）图像传感器有着体积小，质量轻，功耗低，高集成度等特点正逐步取代CCD图像传感器，在空间辐射环境中有着质子，重粒子，γ射线，电子等大量的高能粒子，CMOS图像传感器会受到重离子的辐射效应并对其有着永久损伤的影响。本文主要是针对CMV4000在重离子辐照下的永久损伤机制。CMV4000在经过重离子辐照过后其图像有着明显的热像素（暗电流尖峰高于其他像素暗电流尖峰数倍通常表现为该像素的灰度值是其他正常像素的数倍），在下一帧图像以及后续图像中热像素也并不会消失，因此热像素并不是暂时的。本文还将考虑 CMOS图像传感器在辐照前后各像参数的对比并揭示各项参数的退化机理。
分类： 其他 分类： 其他 提交时间： 2024-04-25
摘要： The Australia Telescope Large Area Survey (ATLAS) and the VLA survey in the XMM-LSS/VIDEO deep field provide deep ($\approx 15$ ${\mu}$Jybeam$^{-1}$) and high-resolution ($\approx$ 4.5--8 arcsec) radio coverage of the three XMM-SERVS fields (W-CDF-S, ELAIS-S1, and XMM-LSS). These data cover a total sky area of 11.3 deg$^2$ and contain $\approx 11000$ radio components. Furthermore, about 3~deg$^2$ of the XMM-LSS field also has deeper MIGHTEE data that achieve a median RMS of 5.6 ${\mu}$Jy beam$^{-1}$ and detect more than 20000 radio sources. We analyze all these radio data and find source counterparts at other wavebands utilizing deep optical and IR surveys. The nature of these radio sources is studied using radio-band properties (spectral slope and morphology), and the IR-radio correlation. %and spectral energy distribution. Radio AGNs are selected and compared with those selected using other methods (e.g. X-ray). We found 1656 new AGNs that were not selected using X-ray and/or MIR methods. We constrain the FIR-to-UV SEDs of radio AGNs using {\sc cigale} and investigate the dependence of radio AGN fraction upon galaxy stellar mass and star-formation rate.
分类： 其他 分类： 其他 提交时间： 2024-04-25
摘要： We present X-ray spectral and long-term variability analyses of an unbiased sample of 361 optically selected radio-loud quasars (RLQs) utilizing sensitive serendipitous X-ray data from the Chandra and XMM-Newton archives. The spectral and temporal properties of RLQs are compared with those of radio-quiet quasars (RQQs) matched in $L_\mathrm{2500A}$ and $z$. The median power-law photon index ($\Gamma$) of RLQs is $1.84^{+0.01}_{-0.01}$, which is close to that of matched RQQs ($1.90^{+0.02}_{-0.01}$). No significant correlations between $\Gamma$ and radio-loudness, $L_\mathrm{x}/L_\mathrm{x,rqq}$ (the X-ray luminosity over that expected from the $L_\mathrm{x}$-$L_\mathrm{uv}$ relation for RQQs), redshift, or Eddington ratio are found for our RLQs. The stacked X-ray spectra of our RLQs show strong iron-line emission and a possible Compton-reflection hump. The intrinsic X-ray variability amplitude is $\approx40$% for RLQs on timescales of months-to-years in the rest frame, which is somewhat smaller than for the matched RQQs ($\approx60$%) on similar timescales, perhaps due to the larger black-hole masses and lower Eddington ratios in our RLQ sample. The X-ray spectral and variability results for our RLQs generally support the idea that the X-ray emission of typical RLQs is dominated by the disk/corona, as is also indicated by a recent luminosity correlation study.
分类： 其他 分类： 其他 提交时间： 2024-04-25
摘要： Radio-loud quasars (RLQs) are known to produce excess X-ray emission, compared to radio-quiet quasars (RQQs) of the same luminosity, commonly attributed to jet-related emission. Recently, we found that the HeII EW and $\alpha_{\rm{ox}}$ in RQQs are strongly correlated, which suggests that their extreme-ultraviolet (EUV) and X-ray emission mechanisms are tightly related. Using 48 RLQs, we show that steep-spectrum radio quasars (SSRQs) and low radio-luminosity ($L_{\rm R}$) flat-spectrum radio quasars (FSRQs) follow the $\alpha_{\rm ox}$--HeII EW relation of RQQs. This suggests that the X-ray and EUV emission mechanisms in these types of RLQs is the same as in RQQs, and is not jet related. High-$L_{\rm R}$ FSRQs show excess X-ray emission given their HeII EW by a factor of $\approx$ 3.5, which suggests that only in this type of RLQ is the X-ray production likely jet related.
分类： 其他 分类： 其他 提交时间： 2024-04-25
摘要： Radio-loud quasars (RLQs) are more X-ray luminous than predicted by the X-ray-optical/UV relation (i.e. $L_\mathrm{x}\propto L_\mathrm{uv}^\gamma$) for radio-quiet quasars (RQQs). The excess X-ray emission depends on the radio-loudness parameter ($R$) and radio spectral slope ($\alpha_\mathrm{r}$). We construct a uniform sample of 729 optically selected RLQs with high fractions of X-ray detections and $\alpha_\mathrm{r}$ measurements.We find that steep-spectrum radio quasars (SSRQs; $\alpha_\mathrm{r}\le-0.5$) follow a quantitatively similar $L_\mathrm{x}\propto L_\mathrm{uv}^\gamma$ relation as that for RQQs, suggesting a common coronal origin for the X-ray emission of both SSRQs and RQQs. However, the corresponding intercept of SSRQs is larger than that for RQQs and increases with $R$, suggesting a connection between the radio jets and the configuration of the accretion flow. Flat-spectrum radio quasars (FSRQs; $\alpha_\mathrm{r}>-0.5$) are generally more X-ray luminous than SSRQs at given $L_\mathrm{uv}$ and $R$, likely involving more physical processes. The emergent picture is different from that commonly assumed where the excess X-ray emission of RLQs is attributed to the jets. We thus perform model selection to comparecritically these different interpretations, which prefers the coronal scenario with a corona-jet connection. A distinct jet component is likely important for only a small portion of FSRQs.The corona-jet, disk-corona, and disk-jet connections of RLQs are likely driven by independent physical processes. Furthermore, the corona-jet connection implies that small-scale processesin the vicinity of SMBHs, probably associated with the magnetic flux/topology instead of black-hole spin, are controlling the radio-loudness of quasars.
分类： 其他 提交时间： 2024-04-25
摘要： We have investigated the jet-linked \mbox{X-ray} emission from highly radio-loud quasars (HRLQs; $\log R>2.5$) at high redshift. We studied the X-ray properties of 15 HRLQs at $z>4$, using new {\it Chandra} observations for six objects and archival {\it XMM-Newton} and {\it Swift} observations for the other nine. We focused on testing the apparent enhancement of jet-linked \mbox{X-ray} emission from HRLQs at $z>4$. Utilizing an enlarged (24 objects) optically flux-limited sample with complete X-ray coverage, we confirmed that HRLQs at $z>4$ have enhanced X-ray emission relative to that of HRLQs at $z\approx$ 1--2 with matched UV/optical and radio luminosity, at a \mbox{4.0--4.6}~$\sigma$ level; the X-ray enhancements are confirmed considering both two-point spectral indices and inspection of broad-band spectral energy distributions. The typical factor of enhancement is revised to $1.9^{+0.5}_{-0.4}$, which is smaller than but consistent with previous results. A fractional IC/CMB model can still explain our results at high redshift, which puts tighter constraints on the fraction of IC/CMB X-rays at lower redshifts, assuming the physical properties of quasar jets do not have a strong redshift dependence. A dominant IC/CMB model is inconsistent with our data.
分类： 其他 提交时间： 2024-04-25
摘要： Rapid flares from blazars in very high energy (VHE) $\gamma$-rays challenge the common understanding of jets of active galactic nuclei (AGNs). The same population of ultra-relativistic electrons is often thought to be responsible for both X-ray and VHE emission. We thus systematically searched for X-ray flares at sub-hour timescales of TeV blazars in the entire Rossi X-ray Timing Explorer archival database. We found rapid flares from PKS 2005-489 and S5 0716+714, and a candidate rapid flare from 1ES 1101-232. In particular, the characteristic rise timescale of PKS 2005-489 is less than half a minute, which, to our knowledge, is the shortest among known AGN flares at any wavelengths. The timescales of these rapid flares indicate that the size of the central supermassive black hole is not a hard lower limit on the physical size of the emission region of the flare. PKS 2005-489 shows possible hard lags in its flare, which could be attributed to particle acceleration (injection), its flaring component has the hardest spectrum when it first appears. For all flares, the flaring components show similar hard spectra with $\Gamma=1.7-1.9$, and we estimate the magnetic field strength $B\sim$ 0.1--1.0 G by assuming synchrotron cooling. These flares could be caused by inhomogeneity of the jets. Models that can only produce rapid $\gamma$-ray flares but little synchrotron activity are less favorable.
分类： 其他 分类： 其他 分类： 其他 提交时间： 2024-04-25
摘要： Fluxes emitted at different wavebands from active galactic nuclei (AGNs) fluctuate at both long and short timescales. The variation can typically be characterized by a broadband power spectrum, which exhibits a red-noise process at high frequencies. The standard method of estimating power spectral density (PSD) of AGN variability is easily affected by systematic biases such as red-noise leakage and aliasing, in particular, when the observation spans a relatively short period and is gapped. Focusing on the high-frequency PSD that is strongly distorted due to red-noise leakage and usually not significantly affected by aliasing, we develop a novel and observable normalized leakage spectrum (NLS), which describes sensitively the effects of leaked red-noise power on the PSD at different temporal frequencies. Using Monte Carlo simulations, we demonstrate how an AGN underlying PSD sensitively determines the NLS when there is severe red-noise leakage and thereby how the NLS can be used to effectively constrain the underlying PSD.
分类： 其他 提交时间： 2024-04-25
摘要： 观察耳穴贴压联合耳尖放血治疗一例外感咳嗽病患者的疗效。选取1例外感咳嗽患者，通过耳穴贴压对针对性穴位进行按摩，结合耳尖放血的治疗手法，达到有效改善平衡阴阳、调整脏腑、疏通经络、扶正祛邪、活血止痛，有效缓解患者咳嗽咳痰症状，从而缓解病情，促进康复，临床效果良好，无明显不良反应。
分类： 其他 提交时间： 2024-04-07
摘要： 本文总结1例面肌痉挛患者行火龙罐综合灸治疗的效果观察及护理经验。基于中医辨证施护理论基础上，给予火龙罐综合灸治疗并进行动态观察，同时配合情志护理、生活起居护理等常规护理措施，有效改善了患者的临床症状，缓解患者焦虑，提高了患者的舒适度及生活质量。
分类： 其他 分类： 其他 提交时间： 2024-03-11
摘要： 目的 通过随机对照试验评估中西医结合护理路径对呆病患者效果。方法 选取90名符合入选标准的患者，随机分为试验组（接受中西医结合护理）和对照组（接受常规护理）。在基线、干预第四周和出院后第四周测量MMSE、PSQI、ADL、MNA，进行组间比较。结果 ①MMSE：试验组在干预第四周和随访第四周明显提高（P＜0.05），且显著优于对照组（P＜0.05）。②PSQI：试验组在干预第四周和随访第四周明显下降（P＜0.05），对照组在干预第四周也下降（P＜0.05），试验组明显更佳（P＜0.05）。③ADL：两组无显著差异（P＞0.05）。④MNA：干预第四周两组无显著差异（P＞0.05），试验组随访第四周明显改善（P＜0.05）。结论 中西医结合护理路径对呆病患者病情干预效果较常规护理明显更佳。
分类： 其他 分类： 其他 提交时间： 2024-02-12
摘要： The technical evolution of domestic multi-functional electricity meter is deeply discussed. With the rapid development of the domestic power market and the continuous innovation of technology, the domestic multi-functional electricity meters have experienced the transformation from simple billing to complex multi-functional, from a single application to a wide range of fields. This transformation has not only driven the rapid development of electricity meter technology, but also met the increasing power demand and management requirements. This paper expounds the concept of multi-function meter, the working principle and algorithm of digital multiplier, the initiation and evolution of multi-function electricity meter standard, and the initiation and evolution of domestic multi-function electricity meter products. Although the domestic independent production of multi-functional meter has made great achievements in performance, but in the reliability and key process technology still need to be improved. In addition, the development of communication technology also provides a new opportunity for the progress of electricity meter technology. The application of the new technology provides a more convenient and efficient way for the data transmission and remote management of electricity meters. Domestic multi-functional electricity meters have made remarkable achievements in technology evolution and application and expansion, but they still face some challenges and opportunities. In the future, with the continuous development of the power market and the promotion of smart grid construction, domestic multi-functional electricity meters need to continue to strengthen technological innovation and product research and development, improve the reliability and competitiveness of products, in order to meet higher application needs and market requirements.
分类： 其他 提交时间： 2024-01-23
摘要： 本文总结手指点穴联合艾条灸中医特色技术治疗了一例顽固性呃逆患者的护理体会，在中西医结合治疗基础上辅以中医外治法，通过辨证论治，辨证施护，根据病症选取特殊穴位、采用特殊手法，在整体治疗中起到顺气解郁，和胃降逆的重要作用，其疗效显著，患者呃逆症状消失，创伤小，安全无副作用，为临床提供借鉴。
分类： 其他 分类： 其他 提交时间： 2024-01-22
摘要： 本文总结1例中药水罐疗法治疗气滞血瘀型腰痛患者疼痛的临床疗效。根据该例患者住院期间出现的腰部疼痛症状，通过采用中医护理特色水罐治疗技术，治疗患者腰部疼痛的症状疗效显著，从而提高了患者的生活质量。
分类： 其他 提交时间： 2024-01-07
摘要： 目的 探讨改良固定法在难固定部位自制负压引流中的应用。方法 选取我科2020年4月-2021年5月收治腋肩部、骶尾部、臀部、会阴部、腘窝等难固定部位行自制负压治疗的慢性创面患者34例，为对照组；选取我科2021年7月-2022年8月收治腋肩部、骶尾部、臀部、会阴部、腘窝等难固定部位行自制负压治疗的慢性创面患者34例，为观察组。对照组：自制负压中采用传统透明贴膜固定；观察组：自制负压中采用改良固定法固定。比较两组患者贴膜卷边发生率、负压渗漏发生率、负压更换频次、周围皮肤张力性损伤发生率。结果 观察组贴膜卷边发生率、负压渗漏发生率、负压更换频次、周围皮肤张力性损伤发生率均低于对照组，差异有统计学意义（P＜0.05）。结论 在难固定部位自制负压引流技术中,改良固定法较传统固定更稳妥、有效降低周围皮肤张力性损伤发生率，保证负压的有效性，减少负压的更换频次及治疗费用，减轻病人因换药带来的疼痛，提高患者的满意度。
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