Absorption distribution of an optical beam focused into a turbid medium

The focusing of light into a turbid medium was studied with Monte Carlo simulations. Focusing was found to have a significant effect on the absorption distribution in turbid media when the depth of the focal point (the distance between the focal point and the surface of the turbid media) was less than or comparable with the transport mean free path. Focusing could significantly increase the peak absorption and narrow the absorption distribution. As the depth of the focal point increased, the peak absorption decreased, and the depth of peak absorption increased initially but quickly reached a plateau that was less than the transport mean free path. A refractive-index-mismatched boundary between the ambient medium and the turbid medium deteriorated the focusing effect, increased the absorption near the boundary, lowered the peak absorption, and broadened the absorption distribution

Absorption distribution of an optical beam focused into a turbid medium

The focusing of light into a turbid medium was studied with Monte Carlo simulations. Focusing was found to have a significant effect on the absorption distribution in turbid media when the depth of the focal point (the distance between the focal point and the surface of the turbid media) was less than or comparable with the transport mean free path. Focusing could significantly increase the peak absorption and narrow the absorption distribution. As the depth of the focal point increased, the peak absorption decreased, and the depth of peak absorption increased initially but quickly reached a plateau that was less than the transport mean free path. A refractive-index-mismatched boundary between the ambient medium and the turbid medium deteriorated the focusing effect, increased the absorption near the boundary, lowered the peak absorption, and broadened the absorption distribution

Differential effects of partial and complete loss of TREM2 on microglial injury response and tauopathy.

Alzheimer's disease (AD), the most common form of dementia, is characterized by the abnormal accumulation of amyloid plaques and hyperphosphorylated tau aggregates, as well as microgliosis. Hemizygous missense variants in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) are associated with elevated risk for developing late-onset AD. These variants are hypothesized to result in loss of function, mimicking TREM2 haploinsufficiency. However, the consequences of TREM2 haploinsufficiency on tau pathology and microglial function remain unknown. We report the effects of partial and complete loss of TREM2 on microglial function and tau-associated deficits. In vivo imaging revealed that microglia from aged TREM2-haploinsufficient mice show a greater impairment in their injury response compared with microglia from aged TREM2-KO mice. In transgenic mice expressing mutant human tau, TREM2 haploinsufficiency, but not complete loss of TREM2, increased tau pathology. In addition, whereas complete TREM2 deficiency protected against tau-mediated microglial activation and atrophy, TREM2 haploinsufficiency elevated expression of proinflammatory markers and exacerbated atrophy at a late stage of disease. The differential effects of partial and complete loss of TREM2 on microglial function and tau pathology provide important insights into the critical role of TREM2 in AD pathogenesis

ZIC1 Is Downregulated through Promoter Hypermethylation, and Functions as a Tumor Suppressor Gene in Colorectal Cancer

The transcription factor, Zinc finger of the cerebellum (ZIC1), plays a crucial role in vertebrate development. Recently, ZIC1 has also been found to participate in the progression of human cancers, including medulloblastomas, endometrial cancers, and mesenchymal neoplasms. However, the function of ZIC1 in colon cancer progression has not been defined. In this study, we demonstrate ZIC1 to be silenced or significantly downregulated in colon cancer cell lines. These effects were reversed by demethylation treatment with 5-aza-2′-deoxycytidine (Aza). ZIC1 expression is also significantly downregulated in primary colorectal cancer tissues relative to adjacent non-tumor tissues (p = 0.0001). Furthermore, methylation of ZIC1 gene promoter is frequently detected in primary tumor tissues (85%, 34/40), but not in adjacent non-tumor tissues. Ectopic expression of ZIC1 suppresses cell proliferation and induces apoptosis, which is associated with MAPK and PI3K/Akt pathways, as well as the Bcl-xl/Bad/Caspase3 cascade. To identify target candidates of ZIC1, we employed cDNA microarray and found that 337 genes are downregulated and 95 genes upregulated by ectopic expression of ZIC1, which were verified by 10 selected gene expressions by qRT-PCR. Taken together, our results suggest that ZIC1 may potentially function as a tumor suppressor gene, which is downregulated through promoter hypermethylation in colorectal cancers

Evaluation of City–Industry Integration Development and Regional Differences under the New Urbanization: A Case Study of Sichuan

As an important focus of China’s new urbanization construction, the policy of “city–industry integration” has played a key role in promoting the sustainable development of urban construction. This paper integrates the three major elements of social service, ecology and environment, and science and technology into the traditional indicator system of “industry, city, and people”. Firstly, the PSO-AHP-EM model was constructed to empower the indicators subjectively and objectively, and the degree of city–industry integration was sorted by the GRA-TOPSIS model. Secondly, the Gini coefficient and Theil index were used to further explore the non-equilibrium of city–industry integration development. Finally, an empirical study was conducted on 18 prefecture-level cities in Sichuan Province from 2010 to 2019, and their development laws were analyzed. The results show that: (1) The weights obtained by the PSO-AHP solution were better than the weights obtained by AHP. (2) The level of city–industry integration in Sichuan was not high, and most cities need to be further developed. (3) The regional difference of city–industry integration was relatively small, and the main source of the difference was Chengdu Plain Economic Zone. This paper puts forward some suggestions to provide scientific support for the evaluation of city–industry integration

Analysis of the nicotinamide phosphoribosyltransferase family provides insight into vertebrate adaptation to different oxygen levels during the water-to-land transition

One of the most important events in vertebrate evolutionary history is the water-to-land transition, during which some morphological and physiological changes occurred in concert with the loss of specific genes in tetrapods. However, the molecular mechanisms underlying this transition have not been well explored. To explore vertebrate adaptation to different oxygen levels during the water-to-land transition, we performed comprehensive bioinformatics and experimental analysis aiming to investigate the NAMPT family in vertebrates. NAMPT, a rate-limiting enzyme in the salvage pathway of NAD+ biosynthesis, is critical for cell survival in a hypoxic environment, and a high level of NAMPT significantly augments oxidative stress in normoxic environments. Phylogenetic analysis showed that NAMPT duplicates arose from a second round whole-genome duplication event. NAMPTA existed in all classes of vertebrates, whereas NAMPTB was only found in fishes and not tetrapods. Asymmetric evolutionary rates and purifying selection were the main evolutionary forces involved. Although functional analysis identified several functionally divergent sites during NAMPT family evolution, invitro experimental data demonstrated that NAMPTA and NAMPTB were functionally conserved for NAMPT enzymatic function in the NAD+ salvage pathway. Insitu hybridization revealed broad NAMPTA and NAMPTB expression patterns, implying regulatory functions over a wide range of developmental processes. The morpholino-mediated knockdown data demonstrated that NAMPTA was more essential than NAMPTB for vertebrate embryo development. We propose that the retention of NAMPTB in water-breathing fishes and its loss in air-breathing tetrapods resulted from vertebrate adaptation to different oxygen levels during the water-to-land transition

Shale formation environment and comprehensive evaluation of shale oil potential of the Lower First Member of Shahejie Formation in Qikou Sag

Bohai Bay Basin is one of the main exploitation areas of continental shale oil resources in China.Qikou Sag, located in the hinterland of the basin, is one of the typical oil and gas rich depressions in Bohai Bay Basin.This paper selects the organic rich shale in the Lower First Member of Shahejie Formation in Qikou Sag as the research object, and comprehensively uses geochemical logging technology and hydrocarbon generation and expulsion simulation technology to describe the shale sedimentary characteristics and comprehensive evaluation of shale oil potential in the Lower First Member of Shahejie Formation in Qikou Sag.The results show that the Lower First Member of Shahejie Formation in Qikou Sag was deposited in the reduction strong reduction environment with high water salinity, rich nutrients, hot and humid climate, suitable for biological mass reproduction and high productivity.Combined with the hydrocarbon generation and expulsion simulation experiment results, the Lower First Member of Shahejie Formation shale in the study area has strong hydrocarbon generation capacity, high hydrocarbon generation efficiency and low oil discharge rate.Most of the generated crude oil is still left in the shale, which has good exploration potential.The Lower First Member of Shahejie Formation shale in the study area contains an appropriate amount of carbonate minerals, which improves the reservoir conditions during diagenesis and provides a good reservoir site for shale oil.The occurrence of transgression in the southwest margin of Qikou Sag affects the enrichment of organic matter in the Lower First Member of Shahejie Formation from the aspects of sedimentary environment, paleoproductivity and its impact on diagenesis.The enrichment of organic matter, high hydrocarbon generation intensity and good reservoir conditions control the large-area distribution of shale oil in the Lower First Member of Shahejie Formation.Shale oil reservoirs in the Lower First Member of Shahejie Formation in the study area can be divided into carbonate rocks and mixed sedimentary rocks.After synthesizing the oil-bearing characteristics of the two reservoirs, it is found that the mineral content and brittleness index of carbonate rocks have a great impact on shale oil-bearing properties.In the process of further exploration, oil reservoirs can be found in the wide and gentle slope area conducive to the formation of structural fractures and the area with high degree of dolomitization in the study area.The favorable exploration intervals are dolomite, dolomitic shale and calcareous shale with developed pores and micro fractures.The research results provide guidance for the exploration and development of shale oil in Qikou Sag