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Brain fluid clearance by pathways including the recently described paravascular glymphatic system is a critical homeostatic mechanism by which metabolic products, toxins, and other wastes are removed from the brain. Brain fluid clearance may be especially important after traumatic brain injury (TBI), when blood, neuronal debris, inflammatory cells, and other substances can be released and/or deposited. Using a non-invasive dynamic positron emission tomography (PET) method that models the rate at which an intravenously injected radiolabeled molecule (in this case 11C-flumazenil) is cleared from ventricular cerebrospinal fluid (CSF), we estimated the overall efficiency of brain fluid clearance in humans who had experienced complicated-mild or moderate TBI 3?6 months before neuroimaging (n?=?7) as compared to healthy controls (n?=?9). While there was no significant difference in ventricular clearance between TBI subjects and controls, there was a significant group difference in dependence of ventricular clearance upon tracer delivery/blood flow to the ventricles. Specifically, in controls, ventricular clearance was highly, linearly dependent upon blood flow to the ventricle, but this relation was disrupted in TBI subjects. When accounting for blood flow and group-specific alterations in blood flow, ventricular clearance was slightly (non-significantly) increased in TBI subjects as compared to controls. Current results contrast with past studies showing reduced glymphatic function after TBI and are consistent with possible differential effects of TBI on glymphatic versus non-glymphatic clearance mechanisms. Further study using multi-modal methods capable of assessing and disentangling blood flow and different aspects of fluid clearance is needed to clarify clearance alterations after TBI.

Abstract Background Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer’s disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. Methods 24 cognitively normal subjects (≥ 65 years) were dynamically PET imaged for 60 min. using [1-11C]-Butanol. Imaging with either [11C]-PiB or [18F]-FBB identified 8 amyloid PET positive (Aβ+) and 16 Aβ- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. Results LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the Aβ+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. Conclusion The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease.

Abstract There are no models for assessing the factors that determine moderate to poor performance status in patients with cancer after chemotherapy. This study investigated the influencing factors and identified the best model for predicting moderate–poor performance status. A convenience sampling method was used. Demographic and clinical data and evaluation results for fatigue, pain, quality of life and Eastern Cooperative Oncology Group status were collected three days after the end of chemotherapy. Decision tree, random forest and logistic regression models were constructed. Ninety-four subjects in the case group had moderate to poor performance status, and 365 subjects in the control group had no or mild activity disorders. The random forest model was the most accurate model. Physical function, total protein, general quality of life within one week before chemotherapy, hemoglobin, pain symptoms and globulin were the main factors. Total protein and hemoglobin levels reflect nutritional status, and globulin levels are an index of liver function. Therefore, physical function, nutritional status, general quality of life and pain symptoms within one week before chemotherapy and liver function can be used to predict moderate–poor performance status. Nurses should pay more attention to patients with poor physical function, poor nutritional status, lower quality of life and pain symptoms after chemotherapy.

In this paper, we present a novel approach to radiometric normalization for aerial images, effectively addressing both intra- and inter-image color and illumination inconsistencies caused by varying sensor technologies, atmospheric conditions, and ground reflection. We introduce a comprehensive mathematical model for radiance transfer, which addresses brightness inhomogeneities resulting from the Bidirectional Reflectance Distribution Function (BRDF) effect and vignetting effect, alongside color inconsistencies due to atmospheric and illumination variations. To enhance the model's efficiency and stability for solutions, we employ a strategy that leverages multiple polynomial models for approximation, significantly simplifying the complexity of rigorous solutions. Our efficient and robust solution leverages advanced radiometric triangulation theories, enabling effective radiometric normalization of aerial images. We validate the efficacy of our method with extensive testing on three large datasets, each containing over two hundred aerial images. The experimental results showcase our method's superiority over state-of-the-art methods, as evidenced by enhanced visual quality and improved quantitative performance in statistical assessments.

In order to study changes in the characteristic flavor of ultra-high temperature sterilized (UHT) milk under the influence of storage temperature and light, headspace solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to detect the volatile flavor components of the product. Descriptive sensory evaluation, orthogonal partial least squares-discriminant analysis (OPLS-DA) and entropy weight method were used to determine the relationship between major characteristic flavors and characteristic substances. The effects of temperature and light flux on the flavor changes of different formulations of UHT milk were analyzed, and a model for comprehensive analysis of the characteristic flavors of UHT milk was developed based on the effects of initial unsaturated fatty acid content, temperature and light flux. The results of this research provide support for the quality control of different formulations of UHT milk.

In order to clarify the effect of total pressure on the corrosion behavior of steel in the CO2/H2S/O2 system, the high temperature and high pressure reaction vessel, scanning electron microscope and its accompanying energy spectrometer, X-ray diffractometer, 3D optical profiler, and other instruments were employed to research the effect of the different total pressur on the corrosion behavior of L360NS steel in CO2/H2S/O2 system. Results showed that when the total pressure changed within the range of 0.2~1.5 MPa, the uniform corrosion rate of L360NS steel increased with the increase of total pressure. The reason might be that the increase in total pressure led to an increase in gas content in the solution, which accelerated the corrosion reaction kinetics and exacerbated corrosion. Moreover, the bottom of the corrosion product film was a mixture of wedge-shaped and granular products, while the surface was granular. The product composition was FeCO3, Fe2O3, FeS, and FeS2. Besides, with increasing the total pressure, the number of corrosion pits increased in the form of vertical and horizontal extension, and the local corrosion degree became deeper, which was due to the uneven protection of the substrate by corrosion products such as FeCO3, Fe sulfides, and Fe2O3 oxides.

To study the corrosion behavior of three commonly used steels in associated gas pipelines in the three-gas coexistence system of H2S-CO2-O2 can provide guidance for the corrosion prevention and control of associated gas pipelines in Tahe oilfield.Based on the typical corrosion working conditions in Tahe oilfield and taking 20 steel，L245NS steel and 3Cr steel as the research objects，the corrosion rates and corrosion products of the three steels under typical working conditions in H2S - CO2- O2 coexistence system were studied through high -temperature and high-pressure reactor experiment.Results showed that the corrosion rate of 20＃ steel was the highest，followed by L245NS steel，and the corrosion rate of 3Cr steel was the lowest.The corrosion products of the three pipes were mainly Fe，FeS，FeCO3 and Fe2O3.The corrosion resistance behaviors of four typical internal anti-corrosion coatings in Tahe oilfield were studied through an adhesion test and the weight gain method that involved the measuring of the weight gain before and after corrosion，and the results indicated that coating 2 possessed the optimal corrosion resistance and adhesion.Considering the cost performance，“L245NS+coating 2”was finally selected as the anti-corrosion measure for the associated gas pipelines in Tahe Oilfield.

For clarifying the growth characteristics of sulfate reducing bacteria in shale gas pipelines, water samples were collected from a shale gas-gathering pipeline, and the sulfate reducing bacteria(SRB) in the samples were enriched and purified. The DNA of SRB was extracted, and then the gene amplification technology(Polymerase Chain Reaction, PCR) was utilized to describe the characteristics of SRB community. Furthermore, the growth characteristics of SRB in dissolved oxygen environment were quantitatively tested. Results showed that the SRB in shale gas gathering pipeline were mainly Bacteroidota, Firmicutes and Desulfobacterota. The concentration of dissolved oxygen had an impact on the growth and metabolism of SRB. Under a dissolved oxygen concentration of 0~2.5 mg/L, SRB could still grow and reproduce in large quantities. Furthermore, under a dissolved oxygen concentration of 4.5 mg/L and above, the growth and metabolism of SRB were completely inhibited, indicating that SRB were able to grow and reproduce under low O2 concentration in the shale gas gathering pipeline.

Abstract In rodents, hypothalamic inflammation plays a critical role in aging and age-related diseases. Hypothalamic inflammation has not previously been assessed in vivo in humans. We used Positron Emission Tomography (PET) with a radiotracer sensitive to the translocator protein (TSPO) expressed by activated microglia, to assess correlations between age and regional brain TSPO in a group of healthy subjects (n = 43, 19 female, aged 23–78), focusing on hypothalamus. We found robust age-correlated TSPO expression in thalamus but not hypothalamus in the combined group of women and men. This pattern differs from what has been described in rodents. Prominent age-correlated TSPO expression in thalamus in humans, but in hypothalamus in rodents, could reflect evolutionary changes in size and function of thalamus versus hypothalamus, and may be relevant to the appropriateness of using rodents to model human aging. When examining TSPO PET results in women and men separately, we found that only women showed age-correlated hypothalamic TSPO expression. We suggest this novel result is relevant to understanding a stark sex difference in human aging: that only women undergo loss of fertility—menopause—at mid-life. Our finding of age-correlated hypothalamic inflammation in women could have implications for understanding and perhaps altering reproductive aging in women.

To make an effective correlation analysis on the factors influencing the corrosion and perforation of high sulfur associated gas pipeline in Tahe Oilfield, the pipeline flow parameters were calculated using multiphase flow transient model, and a method combining Pearson correlation coefficient with Apriori association rule mining algorithm was proposed to determine the associativity rules that affecting corrosion perforation. Results showed that the multiphase flow transient model revealed the variation laws of pipeline temperature, pressure, flow rate, and liquid holdup along the pipeline. Meanwhile, the degrees of influences of medium parameters and flow parameters on corrosion were as follow: liquid holdup (0.732) > temperature (0.696) > pressure (0.677) =CO2 partial pressure (0.677) = H2S partial pressure (0.677) > gas flow rate (0.618) = gas wall shear force (0.618) > pipe inclination (0.577). The strong correlation rules between the corrosion rate and H2S partial pressure, temperature, liquid holdup, flow rate and pipeline inclination were determined. Besides, the correctness of the association rules was further verified by the high temperature and high pressure dynamic reactor experiment.

The growing demands for material longevity in marine environments necessitate the development of highly efficient, low-cost, and durable corrosion-protective coatings. Although magnesium alloys are widely used in the automotive and aerospace industries, severe corrosion issues still hinder their long-term service in naval architecture. In the present work, an epoxy composite coating containing sericite nanosheets is prepared on the AZ31B Mg alloy using a one-step electrophoretic deposition method to improve corrosion resistance. Due to the polyetherimide (PEI) modification, positively charged sericite nanosheets can be highly orientated in an epoxy coating under the influence of an electric field. The sericite-incorporated epoxy coating prepared in the emulsion with 4 wt.% sericite exhibits the highest corrosion resistance, with its corrosion current density being 6 orders of magnitude lower than that of the substrate. Electrochemical measurements and immersion tests showed that the highly orientated sericite nanosheets in the epoxy coating have an excellent barrier effect against corrosive media, thus significantly improving the long-term anti-corrosion performance of the epoxy coating. This work provides new insight into the design of lamellar filler/epoxy coatings with superior anticorrosion performance and shows promise in the corrosion protection of magnesium alloys.

X65 carbon steel is widely used in subsea gathering and transportation pipelines. In the gathering and transportation process, the natural gas medium is complex and often contains corrosive gases such as H2S and CO2. Due to the use of wet gas transportation, condensate water was formed, resulting in serious corrosion perforation accidents of pipelines. In this work, through the experiments of high - temperature and high - pressure reactor, the corrosion mechanism of gas phase, liquid phase and gas - liquid interface were analyzed, which provided a basis for the formulation of corrosion prevention and control measures for X65 steel wet gas gathering and transmission pipeline. Moreover, high - temperature and high - pressure reactor experiments were carried out with X65 steel in the presence of CO2, H2S and Cl - respectively. Each experiment was carried out for 7 d for gas - liquid interface corrosion, and the characteristics of corrosion products were analyzed by surface analysis technologies, such as scanning electron microscope (SEM) and X - ray diffraction (XRD). Results showed that with the injection of CO2 and H2S, the local corrosion rate increased in three regions of gas phase, liquid phase, and gas - liquid interface. In the presence of CO2 and H2S, the order of corrosion rate was liquid phase corrosion rate > gas phase corrosion rate > interface corrosion rate. Under the condition of gas - liquid interface, X65 steel formed anode below the interface and cathode above the interface, so that the local corrosion rate of liquid phase was faster.

For determining the corrosion behavior of L320 steel at different flow rates in CO2/O2 environments, the flow state of the target pipeline was simulated through the multiphase flow transient simulation software, and the flow velocity range of the indoor simulation experiment was determined. The L320 steel was selected for the high temperature and high pressure dynamic reactor experiment with different flow rates under the CO2/O2 coexistence systems, and the corrosion products were studied by scanning electron microscope and X - ray diffractometer for the microscopic morphology observation and composition analysis. Results showed that the temperature and pressure showed a downward trend with increasing mileage, and the gas flow rate and wall shear force of the pipeline exhibited a gradually increasing trend with the increase of the mileage. Based on the Pearson correlation coefficient method, it was determined that the flow velocity was the main controlling factor affecting the corrosion rate. With the increase of flow rate, the uniform corrosion rate of L320 under the condition of CO2/O2 coexistence gradually increased. The corrosion products of the CO2/O2 coexistence systems were Fe2O3, FeOOH, Fe(OH)3, Fe3O4, FeCO3, etc. The research conclusions could provide reference for the protection of L320 steel in CO2/O2 coexistence environment at different flow rates.

Summary: Bone cancer pain is a common symptom in cancer patients with bone metastases and its underlying mechanisms remain unknown. Here, we report that Runx1 directly upregulates the transcriptional activity of P2X3 receptor (P2X3R) gene promoter in PC12 cells. Knocking down Runx1 in dorsal root ganglion (DRG) neurons suppresses the functional upregulation of P2X3R, attenuates neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats, whereas overexpressing Runx1 promotes P2X3R gene transcription in DRG neurons, induces neuronal hyperexcitability and pain hypersensitivity in naïve rats. Activation of GDNF-GFRα1-Ret-ERK signaling is required for Runx1-mediated P2X3R gene transcription in DRG neurons, and contributes to neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats. These findings indicate that the Runx1-mediated P2X3R gene transcription resulted from activation of GDNF-GFRα1-Ret-ERK signaling contributes to the sensitization of DRG neurons and pathogenesis of bone cancer pain. Our findings identify a potentially targetable mechanism that may cause bone metastasis-associated pain in cancer patients.

Neural circuits that control aversion are essential for motivational regulation and survival in animals. The nucleus accumbens (NAc) plays an important role in predicting aversive events and translating motivations into actions. However, the NAc circuits that mediate aversive behaviors remain elusive. Here, we report that tachykinin precursor 1 (Tac1) neurons in the NAc medial shell regulate avoidance responses to aversive stimuli. We show that NAcTac1 neurons project to the lateral hypothalamic area (LH) and that the NAcTac1→LH pathway contributes to avoidance responses. Moreover, the medial prefrontal cortex (mPFC) sends excitatory inputs to the NAc, and this circuit is involved in the regulation of avoidance responses to aversive stimuli. Overall, our study reveals a discrete NAc Tac1 circuit that senses aversive stimuli and drives avoidance behaviors.