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This article has been withdrawn due to a publisher error that caused the article to be duplicated. The definitive version of this article is published under DOI https://doi.org/10.1093/pnasnexus/pgad075.

Post-yield softening (PYS) plays an important role in guiding the design of high-performance energy-absorbing lattice materials. PYS is usually restricted to lattice materials that are stretching dominated according to the Gibson–Ashby model. Contrary to this long-held assumption, this work shows that PYS can also occur in various bending-dominated Ti-6Al-4V lattices with increasing relative density. The underlying mechanism for this unusual property is elucidated using the Timoshenko beam theory. It is attributed to the increase in stretching and shear deformation with increasing relative density, thereby increasing the tendency towards PYS. The finding of this work extends perspectives on PYS for the design of high-performance energy-absorbing lattice materials.

患儿8月龄起病以脾脏、淋巴结和腮腺肿大为突出表现，伴反复发热、窦肺感染、贫血和血小板减少，外周血多克隆性B细胞增殖。基因检出半胱天冬酶募集结构域11基因第5外显子新发杂合变异（c.368CT，p.G123D），父母为野生型，诊断NF-κB相关B细胞增殖和T细胞失能性疾病。经10年利妥昔单抗治疗，淋巴增殖控制良好。.

The fatigue strength deterioration in Ti–6Al–4V specimens impacted by steel sphere was experimentally investigated. Based on the test data of Peterson’s formula and the fatigue notch factor, the relationships linking the fatigue notch factor, fatigue strength, injury notch size, and stress ratio were derived. The effect of the notch dimension, residual stress, and stress ratio on the fatigue strength is discussed. The main conclusion is that the impact damage-induced reduction of the fatigue strength depends on the ratio between notch depth and notch radius: the greater the ratio, the more pronounced the reduction. Furthermore, the greater the stress ratio, the less id the reduction. These findings have a certain reference value for blade protection design against foreign object damage, the standard-setting, and maintenance guidelines.

Two recent studies of the evolution of the isoscalar giant monopole resonance (ISGMR) within the calcium isotope chain report conflicting results. One study suggests that the monopole resonance energy, and thus the incompressibility of the nucleus $K_{A}$ increase with mass, which implies that $K_{\tau}$, the asymmetry term in the nuclear incompressibility, has a positive value. The other study reports a weak decreasing trend of the energy moments, resulting in a generally accepted negative value for $K_{\tau}$. An independent measurement of the central region of the ISGMR in the Ca isotope chain is provided to gain a better understanding of the origin of possible systematic trends. Inelastically scattered $\alpha$ particles from a range of calcium targets ($\mathrm{^{40,42,44,48}Ca}$), observed at small scattering angles including 0$^\circ$, were momentum analyzed in the K600 magnetic spectrometer at iThemba LABS, South Africa. Monopole strengths spanning an excitation-energy range between 9.5 and 25.5 MeV were obtained using the difference-of-spectra (DoS) technique. The structure of the $E0$ strength distributions of $^{40,42,44}$Ca agrees well with the results from the previous measurement that supports a weak decreasing trend of the energy moments, while no two datasets agree in the case of $^{48}$Ca. Despite the variation in the structural character of $E0$ strength distribution from different studies, we find for all datasets that the moment ratios, calculated from the ISGMR strength in the excitation-energy range that defines the main resonance region, display at best only a weak systematic sensitivity to a mass increase. Different trends observed in the nuclear incompressibility are caused by contributions to the $E0$ strength outside of the main resonance region, and in particular for high excitation energies., Comment: 11 pages, 11 figures, submitted to Physical Review C

Free and fixed plate blade root states were simulated with finite element analysis to reveal the crack effect on the natural vibration frequency of the blade. Natural vibration frequencies are obtained for blades with different crack locations and lengths. The crack is found to reduce the blade stiffness and to affect its natural vibration frequency. The longer the crack, the greater the change of the stiffness, and the more the natural vibration frequency decreases. In the free state, the effect of the cracks of the same length on the natural vibration frequency is basically identical when it lies between the two nodal lines of first-order bending vibrations. The crack effect at a height of one-half the blade in the free state on natural frequencies is very close to that of the cracks of the same length at a height of one-eighth the blade in the fixed state. Practical guidelines for the detection of fracture cracks are given and the crack length and location were evaluated by frequency variations.

Carbon burning is a key step in the evolution of massive stars, Type 1a supernovae and superbursts in x-ray binary systems. Determining the ^{12}C+^{12}C fusion cross section at relevant energies by extrapolation of direct measurements is challenging due to resonances at and below the Coulomb barrier. A study of the ^{24}Mg(α,α^{'})^{24}Mg reaction has identified several 0^{+} states in ^{24}Mg, close to the ^{12}C+^{12}C threshold, which predominantly decay to ^{20}Ne(ground state)+α. These states were not observed in ^{20}Ne(α,α_{0})^{20}Ne resonance scattering suggesting that they may have a dominant ^{12}C+^{12}C cluster structure. Given the very low angular momentum associated with sub-barrier fusion, these states may play a decisive role in ^{12}C+^{12}C fusion in analogy to the Hoyle state in helium burning. We present estimates of updated ^{12}C+^{12}C fusion reaction rates.

The necrotrophic pathogen

Background: Nuclei in the $sd$ shell demonstrate a remarkable interplay of cluster and mean-field phenomena. The $N=Z$ nuclei, such as $^{24}\mathrm{Mg}$ and $^{28}\mathrm{Si}$, have been the focus of the theoretical study of both phenomena in the past. A variety of different cluster structures in these nuclei are predicted, characterized by isoscalar dipole and monopole transitions. For example, low-energy isoscalar vortical dipole states were predicted in $^{24}\mathrm{Mg}$. The cluster and vortical mean-field phenomena can be probed by excitation of isoscalar monopole and dipole states in scattering of isoscalar particles such as deuterons or $\ensuremath{\alpha}$ particles.Purpose: We investigate, both experimentally and theoretically, the isoscalar dipole $IS1$ and monopole $IS0$ strengths in three essentially different light nuclei with different properties: stiff prolate $^{24}\mathrm{Mg}$, soft prolate $^{26}\mathrm{Mg}$, and soft oblate $^{28}\mathrm{Si}$. We analyze possible manifestations of clustering and vorticity in these nuclei.Methods: Inelastically scattered $\ensuremath{\alpha}$ particles were momentum analyzed in the K600 magnetic spectrometer at iThemba LABS, Cape Town, South Africa. The scattered particles were detected in two multiwire drift chambers and two plastic scintillators placed at the focal plane of the K600. In the theoretical discussion, the Skyrme quasiparticle random-phase approximation (QRPA) and antisymmetrized molecular dynamics $+$ generator coordinate method ($\mathrm{AMD}+\mathrm{GCM}$) were used.Results: A number of isoscalar monopole and dipole transitions were observed in the nuclei studied. Using this information, suggested structural assignments have been made for the various excited states. $IS1$ and $IS0$ strengths obtained within QRPA and $\mathrm{AMD}+\mathrm{GCM}$ are compared with the experimental data. The QRPA calculations lead us to conclude that (i) the mean-field vorticity appears mainly in dipole states with $K=1$, (ii) the dipole (monopole) states should have strong deformation-induced octupole (quadrupole) admixtures, and (iii) near the $\ensuremath{\alpha}$-particle threshold there should exist a collective state with $K=0$ for prolate nuclei and $K=1$ for oblate nuclei, with an impressive octupole strength. The results of the $\mathrm{AMD}+\mathrm{GCM}$ calculations suggest that some observed states may have a mixed (mean-field $+$ cluster) character or correspond to particular cluster configurations.Conclusion: A tentative correspondence between observed states and theoretical states from QRPA and $\mathrm{AMD}+\mathrm{GCM}$ was established. The QRPA and $\mathrm{AMD}+\mathrm{GCM}$ analysis shows that low-energy isoscalar dipole states combine cluster and mean-field properties. The QRPA calculations show that the low-energy vorticity is well localized in $^{24}\mathrm{Mg}$, fragmented in $^{26}\mathrm{Mg}$, and absent in $^{28}\mathrm{Si}$.

Three concepts for the application of multi-extreme conditions under in situ neutron scattering are described here. The first concept is a neutron diamond anvil cell made from a non-magnetic alloy. It is shrunk in size to fit existing magnets and future magnet designs and is designed for best pressure stability upon cooling. This will allow for maximum pressures above 10 GPa to be applied simultaneously with (steady-state) high magnetic field and (ultra-)low temperature. Additionally, an implementation of miniature coils for neutron diamond cells is presented for pulsed-field applications. The second concept presents a set-up for laser-heating a neutron diamond cell using a defocused CO2 laser. Cell, anvil, and gasket stability will be achieved through stroboscopic measurements and maximum temperatures of 1500 K are anticipated at pressures to the megabar. The third concept presents a hybrid levitator to enable measurements of solids and liquids at temperatures in excess of 4000 K. This will be accomplished by a combination of bulk induction and surface laser heating and hyperbaric conditions to reduce evaporation rates. The potential for deployment of these multi-extreme environments within this first instrument suite of the Second Target Station is described with a special focus on VERDI, PIONEER, CENTAUR, and CHESS. Furthermore, considerations for deployment on future instruments, such as the one proposed as TITAN, are discussed. Overall, the development of these multi-extremes at the Second Target Station, but also beyond, will be highly advantageous for future experimentation and will give access to parameter space previously not possible for neutron scattering.

Background: Inelastic proton scattering at energies of a few hundred MeV and very-forward angles including $0^\circ$ has been established as a tool to study electric-dipole strength distributions in nuclei. The present work reports a systematic investigation of the chain of stable even-mass Nd isotopes representing a transition from spherical to quadrupole-deformed nuclei. Purpose: Extraction of the equivalent photo-absorption cross sections and analysis of their fine structure in the energy region of the IsoVector Giant Dipole Resonance (IVGDR). Method: Proton inelastic scattering reactions of 200 MeV protons were measured at iThemba LABS in Cape Town, South Africa. The scattering products were momentum-analysed by the K600 magnetic spectrometer positioned at $\theta_{\mathrm{Lab}}=0^\circ$. Using dispersion-matching techniques, energy resolutions of $\Delta E \approx 40 - 50$ keV were obtained. After subtraction of background and contributions from other multipoles, the spectra were converted to photo-absorption cross sections using the equivalent virtual-photon method. Results: Wavelet-analysis techniques are used to extract characteristic energy scales of the fine structure of the IVGDR from the experimental data. Comparisons with the Quasiparticle-Phonon Model (QPM) and Skyrme Separable Random Phase Approximation (SSRPA) predictions provide insight into the role of different giant resonance damping mechanisms. Conclusions: Fine structure is observed even for the most deformed nuclei studied. Fragmentation of the one particle-one hole ($1p1h$) strength seems to be the main source of fine structure in both spherical and deformed nuclei. Some impact of the spreading due to coupling of the two particle-two hole ($2p2h$) states to the $1p1h$ doorway states is seen in the spherical/transitional nuclei, where calculations beyond the $1p1h$ level are available.

幼年型复发性腮腺炎是一种儿童期少见的腮腺非阻塞性炎症性疾病，选择性IgA缺陷是一种抗体缺陷的原发性免疫缺陷病。本文报告1例幼年型复发性腮腺炎合并选择性IgA缺陷病例。.

目的 探讨利妥昔单抗联合短疗程、高强度方案治疗成人Burkitt白血病患者的疗效和安全性。 方法 收集2006年1月30日至2018年9月12日中国医学科学院血液病医院收治的11例Burkitt白血病患者病例资料，分析统计患者的临床特征、完全缓解（CR）率、总生存率、无复发生存率及不良事件。 结果 11例患者中位年龄34（15~54）岁，其中男6例，女5例。发病时中位WBC 12.28（2.21~48.46）×109/L，HGB 113（74~147）g/L，PLT 35（13~172）×109/L，乳酸脱氢酶2 721（803~17 370）U/L，外周血中位原始细胞比例0.40（0.03~0.76），骨髓中位原始细胞比例0.840（0.295~0.945）。10例患者接受利妥昔单抗联合短疗程、高强度化疗，其中2例患者巩固化疗后行自体造血干细胞移植。所有治疗患者1个疗程CR率为100%，4年总生存率为90%，4年无复发生存率为90%。所有治疗患者中，只有1例患者在诱导化疗中出现肿瘤溶解综合征，经血液透析等治疗后肾功能恢复。无治疗相关性死亡病例。 结论 利妥昔单抗联合短疗程、高强度方案治疗成人Burkitt白血病疗效及安全性均较为理想。

Proton inelastic scattering experiments at energy E_p = 200 MeV and a spectrometer scattering angle of 0 degree were performed on 144,146,148,150Nd and 152Sm exciting the IsoVector Giant Dipole Resonance (IVGDR). Comparison with results from photo-absorption experiments reveals a shift of resonance maxima towards higher energies for vibrational and transitional nuclei. The extracted photo-absorption cross sections in the most deformed nuclei, 150Nd and 152Sm, exhibit a pronounced asymmetry rather than a distinct double-hump structure expected as a signature of K-splitting. This behaviour can be related to the proximity of these nuclei to the critical point of the phase shape transition from vibrators to rotors with a soft quadrupole deformation potential. Self-consistent random-phase approximation (RPA) calculations using the SLy6 Skyrme force provide a relevant description of the IVGDR shapes deduced from the present data, Comment: 8 pages, 4 figures

In this work, an electroactive polyimide (EPI) coating with biomimetic surface structure of rose petal used in anticorrosion application was first presented. First of all, amino-capped aniline trimer (ACAT) was synthesized by oxidative coupling reaction, followed by characterized through Fourier transform infrared spectroscooy (FTIR), liquid chromatography – mass spcerometry (LC-MS) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. Subsequently, as-prepared ACAT was reacted with isopropylidenediphenoxy-bis(phthalic anhydride) (BPADA) to give electroactive poly(amic acid) (EPAA). Moreover, poly(dimethylsiloxane) (PDMS) was used to be the soft negative template for pattern transfer from the surface of rose petal to the surface of polymer coating. The EPI coating with biomimetic structure was obtained by programmed heating the EPAA slurry casting onto the negative PDMS template. The anticorrosive performance of as-prepared biomimetic EPI coating was demonstrated by performing a series of electrochemical measurements (Tafel, Nyquist, and Bode plots) upon cold-rolled steel (CRS) electrode in a NaCl aqueous solution. It should be noted that the biomimetic EPI coating with rose petal-like structure was found to exhibit better anticorrosion than that of EPI without biomimetic structure. Moreover, the surface contact angle of water droplets for biomimetic EPI coating was found to be ~150°, which is significantly higher than that of EPI coating with smooth structure (~87°), indicating that the EPI coating with biomimetic structure reveals better hydrophobicity. The apparent mechanism for improved anticorrosive properties is twofold: (1) the biomimetic structure of EPI coating can repel water droplets. (2) electroactivity of EPI coating promotes the formation of densely passive layer of metal oxide on metallic surface.

目的 探讨急性早幼粒细胞白血病（APL）患者继发治疗相关性髓系肿瘤（t-MN）的临床特点、诊断、治疗及预后。 方法 回顾性分析中国医学科学院血液病医院2012年10月至2019年1月收治的4例APL继发t-MN患者的临床资料，并进行相关文献复习。 结果 4例APL继发t-MN患者均为女性，中位年龄42（40~53）岁，3例接受了以维甲酸（ATRA）+亚砷酸（ATO）为基础联合蒽环/蒽醌类药物±阿糖胞苷的前期诱导缓解及巩固治疗方案，1例采用了ATRA联合蒽环/蒽醌类药物±阿糖胞苷的治疗方案，均没有使用烷化剂。在APL获得完全缓解（CR）后40~43个月出现t-MN，其中治疗相关性骨髓增生异常综合征（t-MDS）1例，治疗相关性急性髓系白血病（t-AML）3例，出现t-MN时PML-RARα融合基因均为阴性。3例t-AML患者接受了2~4个疗程再诱导治疗，其中有1例t-AML患者在获得CR后行异基因造血干细胞移植（allo-HSCT），1例t-MDS患者接受了去甲基化治疗。中位随访54.5（48~62）个月，2例t-AML患者死亡，出现t-MN后中位生存期为12（5~18）个月。1989至2018年文献共报道63例APL继发t-MN病例，与本次报道的4例汇总分析，67例患者中男27例，女40例；中位年龄为52.5（15~76）岁；中位潜伏期39（12~168）个月，确诊t-MN后中位生存时间为10（1~39）个月。 结论 APL继发t-MN较为少见，目前缺乏有效的防治措施，预后不佳，在随访过程中（尤其是获得CR后39个月左右）若出现病情变化，应警惕t-MN的发生，对此类患者应尽快明确疾病的变化，给予合理的治疗。

Extracellular matrix (ECM) provides both physical support and bioactive signals such as growth factors and cytokines to cells at their microenvironment or niche. Engineering the matrix niche becomes an important approach to study or manipulate cellular fate. This work presents an overview on the reconstitution of the ECM niche through a wide range of approaches ranging from coating culture dish with ECM molecules to decellularization of native tissues. In particular, we focused on reconstituting the complex ECM niche through cell-derived matrix (CDM) by reviewing the methodological approaches used in our group to derive ECM from mature cells such as chondrocytes and nucleus pulposus cells (NPCs), undifferentiated stem cells such as mesenchymal stem cells (MSCs), as well as MSCs undergoing chondrogenic and osteogenic differentiation, in 2D or 3D models. Specific attention has also been given to key factors that should be considered in various applications and challenges in relation to the CDM. Last but not the least, a few future perspectives and their significance have been proposed.

目的 探讨符合WHO（2016）诊断分型标准的骨髓增生异常综合征（MDS）5q−综合征患者的临床特征、来那度胺（LEN）疗效和生存情况。 方法 回顾性分析2008年1月至2018年4月于中国医学科学院血液病医院就诊的77例符合WHO（2016）诊断分型标准的MDS 5q−综合征患者临床资料，比较单纯5q−与5q−伴1个非−7/7q−的其他染色体异常（ACA）患者临床特征、疗效及生存情况，并比较LEN与非LEN药物治疗的疗效与生存情况。 结果 77例患者中，单纯5q−者64例，5q−伴ACA者13例，确诊时5q−伴ACA患者的中位年龄显著低于单纯5q−患者[58（29~64）岁对63（31~82）岁，z=2.164，P=0.030]。5q−伴ACA患者CD41免疫组化染色小巨核细胞（直径≤40 µm）检出率（91.7%，11/12）显著高于单纯5q−患者（60.0%，33/55）（P=0.046）。可评估LEN疗效的29例患者中，单纯5q−患者（19例）与5q−伴ACA患者（10例）血液学总反应率（78.9%对80.0%）、血液学完全缓解（CR）率（57.9%对60.0%）、细胞遗传学反应（CyR）率[69.2%（9/13）对66.7%（4/6）]、完全细胞遗传学反应（CCyR）率[61.5%（8/13）对33.3%（2/6）]相当。单纯5q−与5q−伴ACA患者中位总生存（OS）时间差异无统计学意义（62个月对78个月，P=0.313）。29例LEN组患者的血液学总反应率（79.3%对36.0%）、CR率（58.6%对8.0%）、CyR率[68.4%（13/19）对11.1%（1/9）]、CCyR率[52.6%（10/19）对0（0/9）]均高于非LEN组患者（25例），但两组患者中位OS时间差异无统计学意义（78个月对62个月，P=0.297）。 结论 单纯5q−与5q−伴ACA患者临床特征大体相似，两组患者LEN疗效、中位OS时间无明显差异。LEN治疗5q−综合征患者的疗效肯定，优于非LEN药物。

目的 研究免疫表型分析及分子遗传学在急性早幼粒细胞白血病（APL）诊断中的应用价值。 方法 对2012年5月–2017年12月门诊或住院的798例APL患者的流式细胞术（FCM）免疫分型、染色体核型及染色体荧光原位杂交（FISH）进行回顾性分析，并深入研究FCM免疫表型及分子遗传学在APL诊断中的应用价值。 结果 FCM诊断APL敏感性为91.9%，特异性为98.7%。APL具有独特免疫表型特点：典型APL的表型为侧向（SSC）偏大，CD34和HLA-DR表达缺失，表达或强表达CD33，均一表达CD13、CD9、CD123，可伴有CD56、CD7、CD2的表达。约10%的患者为非典型APL表型，一般伴有CD34和（或）HLA-DR表达，SSC减小，经常伴有CD2表达，而FCM免疫分型很难明确诊断为APL，需要依赖遗传学或者分子生物学检查结果。约1/3的患者除存在t（15;17）（q22;q21）外，还存在额外染色体异常；伴有t（15；17）的复杂核型、变异易位或者t（11;17）、t（5;17）等变异型的APL，FCM表型与单纯t（15；17）APL差异无统计学意义（P>0.05）。 结论 FCM能够快速诊断APL，伴有额外染色体异常患者和单纯t（15；17）患者FCM免疫表型没有明显差异。遗传学是诊断APL的金标准，免疫分型中约10%的患者依赖于分子遗传学来确诊。