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Purpose: Phyllospheric microorganisms are among the most vital factors that influence the flavor and taste of coffee (Coffea arabica). Little is known about the relationship between bean properties in C. arabicaand phyllospheric microorganisms. The study was carried out to assess bean morphology and biochemical compositions in Coffea arabicacultivars and correlation analysis between them and phyllospheric microorganisms. Materials: Ten C. arabicaaccessions were collected to assess the factor affecting coffee quality. An extensive variation was determined in terms of the bean morphological and biochemical compositions traits examined between the ten C. arabicaaccessions. Results: Correlation analysis demonstrated that the hundred-grain weight had strong positive correlation with transverse diameter (r= 0.80***) and longitudinal diameter (r= 0.61***). Additionally, strong positive correlation was determined between chlorogenic acid and longitudinal diameter (r= 0.69***), between caffeine and neochlorogenic acid (r= 1.00***), and between isochlorogenic acid B and isochlorogenic acid C (r= 0.74***). Furthermore, among four C. arabicacultivars, highly significant differences for the alpha and beta diversity indices of the pyllospheric bacterial and fungal communities were observed. Besides, T test indicated that the relative abundance of top five phyllospheric bacterial and fungal phyla exhibited significant different enrichment among the four C. arabicavarieties. Conclusion: The redundancy analysis revealed that Proteobacteria were the most correlated with transverse diameter, caffeine, and trigonelline for dominant fungal phylum, and strong correlations were detected between Ascomycota and two bean biochemical compositions (isochlorogenic acid C and crude oil). This study may be useful for promoting the quality and yield of C. arabica.

Pseudo threshold pressure gradient (PTPG) is one of the main factors affecting the oil recovery of heterogeneous low-permeability and tight reservoirs. When the pressure gradient between the supply boundary and the bottom hole is less than PTPG, the crude oil in the formation cannot flow. In order to accurately measure the relationship between PTPG and permeability, a novel experimental device has been designed and a series of core flooding experiments using brine and oil have been carried out. The new experimental device eliminates the influence of rubber sleeve in core holder and core end-effect on the results, and greatly improves the accuracy of pressure measurement. The experimental results show the PTPG has a power function relationship with permeability, and has no obvious relationship with the viscosity of the fluid. Based on the equation for PTPG and permeability of crude oil and brine fitted by the experimental data, a new heterogeneous reservoir mathematical model considering PTPG were established. The influence of the coefficient of permeability variation, average permeability, and the production rate on oil recovery factor have been studied by this model. The results clearly show that the coefficient of permeability variation has the greatest influence on oil recovery factor, which represents inhomogeneity in low-permeability and tight reservoirs. Also, when the coefficient of permeability variation is less than a certain value (about 0.2 when average permeability is 1mD, in our model), there is only a slight decline in oil recovery factor, and when coefficient of permeability variation is larger than this value, the oil recovery factor decreases rapidly. The finding is consistent with oil field production and helpful to determine whether to take EOR(enhanced oil recovery) measures for a low-permeability heterogeneous reservoirs.

Alkali/surfactant/polymer (ASP) combines the advantages of each of the chemical in the blend. ASP has shown to be an effective and practical method to enhance oil recovery. Compared with vertical wells, fluid flooding by using horizontal wells is believed to be infeasible due to easier fluid breakthrough and subsequent low sweeping efficiency. However, good responses observed in field applications (Daqing oil field, China) show the promising future of ASP flooding using horizontal wells. In this study, a combination of laboratory-scale core displacement experiments and reservoir-scale numerical simulations was used to study the performances of ASP flooding by using horizontal injection/production wells and vertical injection/production wells to reveal the mechanisms responsible for the favorable responses observed in the field. Firstly, displacement experiments in evaluation of ASP flooding using vertical wells and horizontal wells were conducted. The effects of well type on ASP flooding performances were further evaluated by numerical simulation based on a realistic reservoir. The results show that, horizontal well injection/production pattern facilitates a better oil displacement performance due to the higher sweeping volume. This is because horizontal injection/production pattern weakens both the effects of surface heterogeneity and vertical inter-layer heterogeneity during ASP flooding performance. Although horizontal injection/production well pattern is not suitable for water flooding due to the higher chances for water breakthrough, the profile-control characteristic of ASP system blocks the high permeable channels to some extent, providing a better performance in combination with horizontal injection/production well pattern. This work systematically studied the effects of well type on ASP flooding performance at core scale and reservoir scale, and it provides theoretical and practical implications for the application of ASP flooding in enhancing oil recovery for high water cut reservoirs.

The role of chemotherapy in the treatment of myxofibrosarcoma is unclear. There are no randomized clinical trials evaluating the therapeutic effect of chemotherapy on myxofibrosarcoma. We report, to the best of our knowledge, the first case of myxofibrosarcoma successfully treated with mesna, pirarubicin, ifosfamide and dacarbazine (modified MAID) regimen. The patient achieved complete remission evaluated according to Response Evaluation Criteria in Solid Tumours (RECIST).

Various survival scoring systems have been developed to help surgeons select the best candidates for appropriate therapies in patients with metastatic spinal disease. This study aims to discuss the current status and future directions of scoring systems for the prediction of survival prognosis in these patients. The search terms “spine metastases,” “metastatic spinal disease,” and “metastatic spinal cord compression” were combined with “survival prognosis,” “scoring system,” and “score” to elicit relevant literatures in PubMed and Embase databases. As a result, 159 articles were selected from PubMed, and 246 articles were extracted from Embase. After reviewing each article, we carefully included and analyzed 74 articles about the development and evaluation of scoring systems for predicting survival prognosis in spine metastases. In this review, those scoring systems were stratified into the historic scoring systems and the modern scoring systems on the basis of the proposed time. The historic scoring systems, including the original/revised Tokuhashi scoring system, the Bauer scoring system, the Tomita scoring system, and the Linden scoring system, and the modern scoring systems, such as the Lei scoring system, the Bartels scoring system, the Mizumoto scoring system, the Bollen scoring system, the Rades scoring system, Oswestry Spinal Risk Index, and the Choi risk calculator, were introduced and discussed in this review. Besides, the clinical effectiveness and pitfalls of the existing systems and the future directions of the next generation of scoring systems were also addressed and discussed. We recommended these scoring systems as preferable reference tools to help doctors to select surgical candidates. In patients with long-term life expectancy, radical surgery, such as wide or marginal excision, can be considered in patients with neurological deficits, spine instability, or severe back pain. Besides, with the advancement and improvement of medical technologies, surgical procedures are changing, which can affect surgical indications such as vertebroplasty, minimal invasive surgery, and percutaneous stabilization, which can also be used in patients with spine instability or severe back pain, and do not require much recovery; hence, they can even be used in patients with relative short-term life expectancy. However, the decision about the treatment of patients with metastatic spinal disease is so complicated and should never rely on prognostic scores alone. The final therapeutic decision should be made by interdisciplinary corporations of oncologists, radiologists, and spinal surgeons. Besides, individual intentions should be respected.

The effectiveness of various surfactants in improving crude oil displacement efficiency was evaluated using one-dimensional homogeneous core and three-dimensional heterogeneous models. Emulsification of the crude oil was simulated using an ultrasonic instrument, and the emulsification degree was evaluated based on droplet dispersion, droplet number density, interfacial tension, external phase viscosity, internal phase volume, and demulsification time. Six surfactants could be divided into five emulsifying types: non-emulsification, emulsification inversion, early emulsification, late emulsification, and whole process emulsification. The results showed that the surfactants had varying levels of effectiveness in improving displacement efficiency. The whole process emulsification system can effectively start the residual oil in the pore throat and reduce the free-state and bound-state residual oil saturation. The area of the mainstream zone between the injection and production wells was significantly expanded after the whole process emulsification system was injected. The whole process emulsification is more important than interfacial tension for enhancing oil recovery.

Stress sensitivity phenomenon is an important property in low-permeability and tight reservoirs and has a large impact on the productivity of production wells, which is defined as the effect of effective stress on the reservoir parameters such as permeability, threshold pressure gradient, and rock compressibility change accordingly. Most of the previous works are focused on the effect of effective stress on permeability and threshold pressure gradient, while rock compressibility is critical of stress sensitivity but rarely noticed. A series of rock compressibility measurement experiments have been conducted, and the quantitative relationship between effective stress and rock compressibility is accurately described in this paper. In the experiment, the defects in previous experiments were eliminated by using a new-type core holder. The results show that as the effective stress increases, the rock compressibility becomes lower. Then, a stress sensitivity model that considers the effect of effective stress on rock compressibility is established due to the experimental results. The well performance of a vertical well estimated by this model shows when considering the effect of effective stress on the rock compressibility, the production rate and recovery factor are larger than those without considering it. Moreover, the effect of porosity and confining pressure on the productivity of a vertical well is also studied and discussed in this paper. The results show that the productivity of a vertical well decreases with the increase in overburden pressure, and increases with the increase in the porosity.