Microbial characterisation and stability of a farmhouse natural fermented milk from Spain

This work reports the microbial characterisation of a farmhouse natural fermented milk (NFM) with good sensorial properties produced in Spain. Culturing and denaturing gradient gel electrophoresis (DGGE) analyses showed thatLactococcus lactissubsp.lactis and L. lactissubsp.cremoris(approximate levels of 10⁹ cfu/mL) were dominant in this NFM, whileLactobacillus plantarumappeared at a lower level (10⁶–10⁷ cfu/mL). Repetitive extragenic palindromic (REP)‐PCR typing of the isolates identified single strains each ofLc. lactissubsp.lactis, Lc. lactissubsp.cremorisandLb. plantarum. These three strains formed a stable microbial association which has been maintained for at least some decades.     

ADAPTIVE PREDICTIVE CONTROL: LIMITS OF STABILITY

This paper summarizes the stability results already derived for predictive and adaptive predictive control, discusses them from an intuitive and practical implementation perspective and, from the same perspective, illustrates them by means of two simulated examples. In this way it recalls the limits of stability when applying predictive control and how they are related to the modelling errors, which may change as the process dynamics changes. Also it recalls how, by adding adaptation to the predictive scheme, this source of instability may be compensated for. Already within the adaptive predictive formulation it considers the limits of stability for different scenarios, particularly when a reduced-order adaptive predictive model cannot account for unmodelled process dynamics. © 1997 John Wiley & Sons, Ltd.     

基于知识推理的导向器类零件精铸模具单元体智能切分

导向器类零件分体式精铸的关键技术之一是切分得到蜡模模具设计的内、外环及叶片单元体即如何实现分割面的生成。应用数学推理表达经验知识,得到参数化分割面,为快捷准确的设计与制造导向器类零件精铸模具奠定了基础。     

航空复杂件精铸蜡模数控成型新工艺研究

提出采用NC多轴数控铣削加工工艺直接得到适合精度要求的航空复杂件的精密铸造用蜡模,克服了有模蜡模制造周期长、成本高及无模蜡模快速成型精度低的缺点,实现了航空复杂件精铸蜡模的无模快速精确成型,更好地满足了新机研制对于航空复杂件少量、快速、高精度的要求,对于航空工业的发展意义重大.     

Titanium diffusion in shinbone of rats with osseointegrated implants

Dental implants are composed of commercially pure Ti (which is actually an alloy of titanium, and minor or trace components such as aluminium and vanadium). When the implant is inserted, its surface undergoes a number of chemical and mechanical processes, releasing particles of titanium to the medium. The metabolism of free ions of titanium is uncertain; the uptaking processes in the body are not well known, nor their toxic dose. In addition, physical properties of newly formed bone, such as diffusivity and activation energy, are scarce and rarely studied. In this study, we analysed the diffusion of titanium in the titanium‐implanted shinbones of six adult male Wistar rats by spatially resolved micro x‐ray fluorescence. The measurements were carried out at the microfluorescence station of the x‐ray fluorescence (XRF) beamline of the Brazilian synchrotron facility LNLS (from Portuguese ‘Laboratorio Nacional de Luz Sincrotron’). For each sample, XRF spectra were taken by linear scanning in area near the new bone formed around the Ti implant. The scanning line shows a clear effect of titanium diffusion whereas calcium intensity presents a different behaviour. Moreover, a clear correlation among the different structures of bones is observed in the Ti and Ca intensities. The results obtained in these measurements may allow determining quantitatively the parameters of diffusion rates and other physical properties of new bone like diffusion coefficients.     

<i>In Silico</i> analysis and linking of metabolism-related genes with the immune landscape in head and neck squamous cell carcinoma

Metabolic reprogramming and immunologic suppression are two critical characteristics promoting the progression of head and neck squamous cell carcinoma (HNSCC). The integrative analysis of all the metabolism-related genes (MRGs) in HNSCC is lacking and the interaction between the metabolism and the immune characteristics also requires more exploration to uncover the potential mechanisms. Therefore, this study was designed to establish a prognostic signature based on all the MRGs in HNSCC. Genes of HNSCC samples were available from the TCGA and GEO databases while the MRGs were retrieved from a previous study. Ultimately 4 prognostic MRGs were selected to construct a model possessing robust prognostic value and accuracy in TCGA cohorts. The favorable reproducibility of this model was confirmed in validation cohorts from GEO databases. The risk score calculated by this model was an independent prognostic factor that further classified these HNSCC patients into high-/low-risk groups. GSEA analyses and somatic mutations indicated the low-risk group could activate several anti-tumor pathways and possessed lower TP53 mutation. The results of ESTIMATE, single-sample GSEA, CIBERSORT, and some immune-related molecules analyses suggested the low-risk group exhibited lower metabolic activities and higher immune characteristics. The Spearman correlation test implied most metabolic pathways with tumor-promoting function were negatively correlated with the immune activity, indicating a plausible approach of combining the anti-metabolism and the immunotherapy drugs in the high-risk group to enhance therapeutic effects than applied separately. In conclusion, this prognostic signature linking MRGs with the immune landscape could promote the individualized treatment for HNSCC patients.     

Synthesis and chemical etching of Te/C nanocables

In this paper, Te/C nanocables were fabricated by a hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). The products were characterized in detail by multiform techniques: transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray analysis and Fourier transform infrared (FTIR) spectroscopy. The results showed that the products were nanocables with lengths of several microns, core about 20 nm in diameter, and a surrounding sheath of about 60–80 nm in thickness. Te/C nanocables were tailored freely by chemical etching. Carbonaceous nanotubes and Te/C nanocables with fragmentary Te core were obtained by adjusting time of chemical etching.     

基于博弈视角的交通信息提供与道路收费联合定价模型

针对信息提供和拥堵收费两种交通管制策略, 研究了两种策略联合作用下的定价机制。首先构建了政府、信息提供商决策空间, 在分析出行者路径选择行为的基础上, 给出了交通信息市场占有率计算模型; 然后提出了弹性条件下具有/不具有交通信息的混合交通网络均衡分配模型, 得到了出行者的决策空间, 在此基础上提出了基于博弈视角的交通信息提供与道路收费联合定价模型, 设计了求解算法; 最后, 以一个算例对模型进行了分析。结论表明, 社会收益水平及交通信息的质量都会对交通信息及道路收费价格产生显著的影响。此外, 模型的算例结果还与经验较为吻合, 表明模型的实用性和合理性。