Bibliometric Analysis on Pennisetum Sinese Roxb. in China during 2006-2016

The development prospect of Pennisetum Sinese Roxb. is receiving much concern of domestic researchers. In this paper,literature of Pennisetum Sinese Roxb. was taken as basis,and bibliometric analysis method was used to make statistics of distribution of years,research institutions,authors,and research fields. The results showed that research fields of Pennisetum Sinese Roxb. in China were mainly ecological restoration,accounting for 13. 27% of the total literature; the research took on dynamic and diversified cooperation trend. In recent 5 years,the number of papers significantly increased,accounting for 93. 04% of the total literature. The distribution of authors and regions were relatively concentrated,but the overall level of research is low.

Two-photon absorption and stimulated emission in poly-crystalline Zinc Selenide with femtosecond laser excitation

The optical nonlinearity in polycrystalline zinc selenide(ZnSe),excited with 775 nm,1 kHz femtosecond laser pulses was investigated via the nonlinear transmission with material thickness and the Z scan technique.The measured two photon absorption coefficientβwas intensity dependent,inferring that reverse saturated absorption(RSA)is also relevant dur-ing high intensity excitation in ZnSe.At low peak intensity I<5 GW cm^(-2),we findβ=3.5 cm GW^(-1) at 775 nm.The spec-tral properties of the broad blueish two-photon induced fluorescence(460 nm-500 nm)was studied,displaying self-ab-sorption near the band edge while the upper state lifetime was measured to be τ_(e)~3.3 ns.Stimulated emission was ob-served when pumping a 0.5 mm thick polycrystalline ZnSe sample within an optical cavity,confirmed by significant line narrowing fromΔλ=11 nm(cavity blocked)toΔλ=2.8 nm at peak wavelength λ_(p)=475 nm while the upper state life-time also decreased.These results suggest that with more optimum pumping conditions and crystal cooling,polycrystal-line ZnSe might reach lasing threshold via two-photon pumping atλ=775 nm.

表皮生长因子受体在人头颈部鳞状细胞癌中的作用研究进展

头颈部鳞状细胞癌(head and neck squamous cell carcinoma,HNSCC)是常见的恶性肿瘤,恶性程度较高,患者常出现复发和转移。表皮生长因子受体(epidermal growth factor receptor,EGFR)是重要的癌基因,在头颈鳞癌中广泛过表达,且与HNSCC患者的预后呈负相关,是重要的治疗靶点。但HNSCC中的EGFR靶向治疗效果却不如在非小细胞肺癌治疗中那么有效。近几年的研究发现,EGFR促进肿瘤细胞对治疗耐受的机制可能与其过表达、突变、单核苷酸多态性、入核和自噬有关。本文将就这几个方面进行综述,并探讨如何在HNSCC的治疗中更有效地利用EGFR这一靶点,为探索HNSCC的治疗策略提供新的方向。

Abnormal interfacial bonding mechanisms of multi-material additive-manufactured tungsten-stainless steel sandwich structure

Tungsten(W)and stainless steel(SS)are well known for the high melting point and good corrosion resistance respectively.Bimetallic W-SS structures would offer potential applications in extreme environments.In this study,a SS→W→SS sandwich structure is fabricated via a special laser powder bed fusion(LPBF)method based on an ultrasonic-assisted powder deposition mechanism.Material characterization of the SS→W interface and W→SS interface was conducted,including microstructure,element distribution,phase distribution,and nano-hardness.A coupled modelling method,combining computational fluid dynamics modelling with discrete element method,simulated the melt pool dynamics and solidification at the material interfaces.The study shows that the interface bonding of SS→W(SS printed on W)is the combined effect of solid-state diffusion with different elemental diffusion rates and grain boundary diffusion.The keyhole mode of the melt pool at the W→SS(W printed on SS)interface makes the pre-printed SS layers repeatedly remelted,causing the liquid W to flow into the sub-surface of the pre-printed SS through the keyhole cavities realizing the bonding of the W→SS interface.The above interfacial bonding behaviours are significantly different from the previously reported bonding mechanism based on the melt pool convection during multiple material LPBF.The abnormal material interfacial bonding behaviours are reported for the first time.

General Survey of Soil Seed Bank in China

Soil seed bank refers to the sum of upper litter decay and all survival seeds in the soil. It plays a unique role in restoring the surface vegetation and protecting biodiversity. Chinese scholars have carried out extensive researches on the soil seed bank,and have obtained considerable achievements. On the basis of reading extensive literature,this paper summarized the current research results and found that the research contents of soil seed bank in China mainly involve the following aspects:( i) research method of soil seed bank;( ii) classification system of soil seed bank;( iii) spatial pattern of soil seed bank;( iv) relationship between soil seed bank and surface vegetation;( v) dynamic characteristic and seedling replanting of soil seed bank;( vi) application of soil seed bank in vegetation restoration. On the basis of the above summary,it came up with existing problems and future research direction of China's soil seed bank from system construction,field observation,disciplinary combination,interference factors,and community succession.

Modeling and analyzing dynamics of malaria transmission with host immunity

In this paper,we investigate a compart mental model for malaria transmission,where the host individuals are distributed according to their immune status.The acquired immu nity of malaria is usually booted upon each exposure and gradually declines between the consecutive bouts of the disease.It is assumed that the recovered host individuals may be reinfected due to the immunity waning over time.The existence and stability of equilibria in the system,and the effect of the immunity status on dynamics of the system,are investigated,respectively.The phenomena of multiple endemic equilibria in our model are also observed.Our obtained results show that malaria may keep recurring under the first lower prevalence,however,when malaria is spreading in a population,it may remain at a different endemic level under suitable control strategies.

Realising high aspect ratio 10 nm feature size in laser materials processing in air at 800 nm wavelength in the far-field by creating a high purity longitudinal light field at focus

In semiconductor and data storage device manufacturing,it is desirable to produce feature sizes less than 30 nm with a high depth-to-width aspect ratio on the target material rapidly at a low cost.However,optical diffraction limits the smallest focused laser beam diameter to around half of the laser wavelength(λ/2).The existing approach to achieving nanoscale fabrication is mainly based on costly extreme ultraviolet(EUV)technology operating within the diffraction limit.In this paper,a new method is shown to achieve materials processing resolution down to 10 nm(λ/80)at an infrared laser wavelength of around 800 nm in the far-field,in air,well beyond the optical diffraction limit.A highquality longitudinal field with a purity of 94.7% is generated to realise this super-resolution.Both experiments and theoretical modelling have been carried out to verify and understand the findings.The ablation craters induced on polished silicon,copper,and sapphire are compared for different types of light fields.Holes of 10-30 nm in diameter are produced on sapphire with a depth-to-width aspect ratio of over 16 and a zero taper with a single pulse at 100-120 nJ pulse energy.Such high aspect ratio sub-50 nm holes produced with single pulse laser irradiation are rarely seen in laser processing,indicating a new material removal mechanism with the longitudinal field.The working distance(lens to target)is around 170μm,thus the material processing is in the far field.Tapered nano-holes can also be produced by adjusting the lens to the target distance.

Cancer-associated fibroblasts in breast cancer:Challenges and opportunities

The tumor microenvironment is proposed to contribute substantially to the progression of cancers,including breast cancer.Cancer-associated fibroblasts(CAFs)are the most abundant components of the tumor microenvironment.Studies have revealed that CAFs in breast cancer originate from several types of cells and promote breast cancer malignancy by secreting factors,generating exosomes,releasing nutrients,reshaping the extracellular matrix,and suppressing the function of immune cells.CAFs are also becoming therapeutic targets for breast cancer due to their specific distribution in tumors and their unique biomarkers.Agents interrupting the effect of CAFs on surrounding cells have been developed and applied in clinical trials.Here,we reviewed studies examining the heterogeneity of CAFs in breast cancer and expression patterns of CAF markers in different subtypes of breast cancer.We hope that summarizing CAFrelated studies from a historical perspective will help to accelerate the development of CAF-targeted therapeutic strategies for breast cancer.

Mechanical properties and microstructure characteristics of lattice-surfaced PEEK cage fabricated by high-temperature laser powder bed fusion

Porous structure design on the contact surface is crucial to promote the osseointegration of the intervertebral cage while preventing subsidence and displacement.However,the stress response will undergo significant changes for the current random porous cages,which can directly affect the mechanical properties and long-term usability.Here,this paper proposed a newly designed polyetheretherketone(PEEK)cage with the triply periodic minimal surface(TPMS)-structured lattice surfaces to provide tailored 3 D microporosity and studied the mechanical performance,stress/strain responses,and microstructure changes in depth.The lattice-surfaced PEEK cage mainly exhibits a multiple-point-plane stress transfer mechanism.The compression modulus and elastic limit can be adjusted by controlling the area of the Diamond TPMS surface while the energy absorption efficiency remains stable.The microstructure of high-strength PEEK is featured by the radial pattern morphology.Meanwhile,the double-stranded orthorhombic phase is more ordered,and the benzene plane subunit and lattice volume become more expanded.