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The pore structure of rocks can affect fluid migration and the remaining hydrocarbon distribution. To understand the impacts of the base-level cycle on the pore structure of mouth bar sand bodies in a continental rift lacustrine basin, the pore structure of the mouth bar sand bodies in the ZVC (ZV4 + ZV5) of the Guan195 area was studied using pressure-controlled mercury injection (PMI), casting sheet image and scanning electron microscopy (SEM). The results show that three types of pores exist in ZVC, including intergranular pores, dissolution pores, and micro fractures. The porosity is generally between 1.57% and 44.6%, with a mean value of 19.05%. The permeability is between 0.06 μm2 and 3611 μm2, with a mean value of 137.56 μm2. The pore structure heterogeneity of a single mouth bar sand body in the early stage of the falling period of short-term base-level is stronger than that in the late stage. During the falling process of the middle-term base level, the pore structure heterogeneity of a late single mouth bar sand body is weaker than that of an early single mouth bar sand body. In the long-term base-level cycle, the pore structure heterogeneity of mouth bar sand bodies becomes weaker with the falling of the base-level.

A number of nonlinear acoustic sensing methods exist or are being developed for diverse areas ranging from oceanic sensing of ecosystems, gas bubbles, and submerged objects to medical sensing of the human body. Our approach is to use primary frequency incident waves to generate second order nonlinear sum or difference frequency fields that carry information about an object to be sensed. Here we show that in general nonlinear sensing of an object, many complicated and potentially unexpected mechanisms can lead to sum or difference frequency fields. Some may contain desired information about the object, others may not, even when the intention is simply to probe an object by linear scattering of sum and difference frequency incident waves generated by a parametric array. Practical examples illustrating this in ocean, medical, air and solid earth sensing are given. To demonstrate this, a general and complete second-order theory of nonlinear acoustics in the presence of an object is derived and shown to be consistent with experimental measurements. The total second-order field occurs at sum or difference frequencies of the primary fields and naturally breaks into (A) nonlinear waves generated by wave-wave interactions, and (B) second order waves from scattering of incident wave-wave fields, boundary advection, and wave-force-induced centroidal motion. Wave-wave interactions are analytically shown to always dominate the total second-order field at sufficiently large range and carry only primary frequency response information about the object. As range decreases, the dominant mechanism is shown to vary with object size, object composition, and frequencies making it possible for sum or difference frequency response information about the object to be measured from second-order fields in many practical scenarios. It is also shown by analytic proof that there is no scattering of sound by sound outside the region of compact support intersection of finite-duration plane waves at sum or difference frequencies, to second-order. Analytic expressions for second-order fields due to combinations of planar and far-field wave-wave interactions are also derived as are conditions for when wave-wave interactions will dominate the second order field.

The aim of the study is to investigate the radioprotective effect of polysaccharide extract from Sipunculus nudus (SNP). Beagle dogs were randomly divided into the following six groups. Group-1: Un-treated and un-irradiated controls. Group-2: Exposed to a single acute dose of 2 Gy γ-radiation alone. Groups-3, 4 and 5: Oral administration of SNP at 50, 100 or 200 mg/kg body weight once a day for 7 days followed by a single acute whole body exposure to 2 Gy γ-radiation. The same doses of SNP were administered for further 27 days. Group-6: Positive controls treated with 1.6 mg/kg Nilestriol by gavage after radiation. Blood parameters including white/red cells and platelet counts, as well as hemoglobin level, were assessed every other day for 34 days (7 days before and 27 days of experiment). Serum separated from aliquots of the same blood sample was used to estimate enzyme activity of antioxidant superoxide-dismutase, and to determine levels of free radical, nitric oxide, hydroxyl and superoxide anion. At the end of the experiment, all dogs were euthanized to weigh the organs for organ co-efficient calculation. Pathological changes were assessed in the bone marrow. The results showed that the dogs exposed to γ-radiation alone exhibited a typical hematopoietic syndrome. In contrast, at the end of 27 days experiment, dogs received oral administration of SNP+γ-radiation showed: (i) a much improved blood picture as indicated by shorter duration of leucopenia, neutropenia, thrombocytopenia (platelet counts), as well as hemoglobin levels, (ii) significantly improved hematopoietic activity in the bone marrow, (iii) substantial decrease in nitric oxide levels, and notable increase in activity of antioxidant superoxide dismutase. The results suggested that oral administration of SNP in Beagle dogs was effective in facilitating the recovery of hematopoietic bone marrow damage induced by γ-radiation.

Background: Mortality in cancer patients is directly attributable to the ability of cancer cells to metastasize to distant sites from the primary tumor. This migration of tumor cells begins with a remodeling of the local tumor microenvironment, including changes to the extracellular matrix and the recruitment of stromal cells, both of which facilitate invasion of tumor cells into the bloodstream. In breast cancer, it has been proposed that the alignment of collagen fibers surrounding tumor epithelial cells can serve as a quantitative image-based biomarker for survival of invasive ductal carcinoma patients. Specific types of collagen alignment have been identified for their prognostic value and now these tumor associated collagen signatures (TACS) are central to several clinical specimen imaging trials. Here, we implement the semi-automated acquisition and analysis of this TACS candidate biomarker and demonstrate a protocol that will allow consistent scoring to be performed throughout large patient cohorts. Methods: Using large field of view high resolution microscopy techniques, image processing and supervised learning methods, we are able to quantify and score features of collagen fiber alignment with respect to adjacent tumor-stromal boundaries. Results: Our semi-automated technique produced scores that have statistically significant correlation with scores generated by a panel of three human observers. In addition, our system generated classification scores that accurately predicted survival in a cohort of 196 breast cancer patients. Feature rank analysis reveals that TACS positive fibers are more well-aligned with each other, are of generally lower density, and terminate within or near groups of epithelial cells at larger angles of interaction. Conclusion: These results demonstrate the utility of a supervised learning protocol for streamlining the analysis of collagen alignment with respect to tumor stromal boundaries.