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1.
Adv Sci (Weinh) ; : e2403379, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940419

ABSTRACT

Traditional anti-impact armors and shields are normally made of stiff and hard materials and therefore deficient in flexibility. This greatly limits their applications in protecting objects with complex geometries or significant deformability. Flexible armors can be developed with the application of hard platelets and soft materials, but the lower rigidity of the flexible armors renders them incapable of providing sufficient resistance against impact attacks. To address the inherent conflict between flexibility and impact resistance in traditional armors, here, a composite is developed by hybridizing a shear-stiffening gel as the matrix and chemically-strengthened ultrathin glass sheets (CSGS) as the reinforcement. The resulting laminate, termed PCCL, exhibits both high flexibility and high impact resistance. Specifically, at low strain rates, the high ductility of the gel combined with the high flexural strength of the CSGS enables the PCCL to undergo considerable deformation; at high strain rates, on the other hand, the shear stiffening behavior of the gel matrix endows the PCCL with excellent impact resistance manifested by its high performance in energy absorption and high rigidity. With the combination of high flexibility and high impact resistance, the PCCL is demonstrated to be an ideal armor for protecting curved vulnerable objects from impact attacks.

2.
Nat Commun ; 14(1): 592, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36737606

ABSTRACT

The great challenge for the growth of non-centrosymmetric 2D single crystals is to break the equivalence of antiparallel grains. Even though this pursuit has been partially achieved in boron nitride and transition metal dichalcogenides (TMDs) growth, the key factors that determine the epitaxy of non-centrosymmetric 2D single crystals are still unclear. Here we report a universal methodology for the epitaxy of non-centrosymmetric 2D metal dichalcogenides enabled by accurate time sequence control of the simultaneous formation of grain nuclei and substrate steps. With this methodology, we have demonstrated the epitaxy of unidirectionally aligned MoS2 grains on a, c, m, n, r and v plane Al2O3 as well as MgO and TiO2 substrates. This approach is also applicable to many TMDs, such as WS2, NbS2, MoSe2, WSe2 and NbSe2. This study reveals a robust mechanism for the growth of various 2D single crystals and thus paves the way for their potential applications.

3.
Front Cardiovasc Med ; 9: 910288, 2022.
Article in English | MEDLINE | ID: mdl-36324742

ABSTRACT

Introduction: Degos disease, also known as malignant atrophic papulosis (MAP), is a rare systemic obstructive vascular disease with unknown pathophysiology, which can affect multiple systems, especially gastrointestinal tract and central nervous system. Intestinal perforations with MAP is associated with high mortality rate and ambiguous treatment outcomes. Case presentation: Here we report a missed-opportunity case of Degos disease characterized by generalized skin eruption and multiple intestinal perforations. Definite diagnosis of Degos disease was finally concluded after two exploratory laparotomy operations and skin biopsies. Due to the delayed diagnosis and treatment, the patient died after being discharged automatically in spite of application of aspirin and low-dose subcutaneous heparin. In view of such circumstances, we searched the Pubmed using "Degos [Title] OR Malignant Atrophic Papulosis [Title]" AND "perforation [Title] OR perforations [Title]" and make a detailed analysis of the result. Conclusions: Degos disease is a rare systemic obstructive vascular disease with unknown pathologic mechanism and unavailable treatment methods. Diagnosis is usually based on the presence of pathognomonic skin lesions and tissue biopsy. Gastrointestinal involvement can cause serious and lethal conditions with high mortality. Currently, how to achieve a satisfying prognosis of MAP with intestinal perforations becomes the most urgent problem in front of medical staff.

4.
Front Vet Sci ; 9: 923449, 2022.
Article in English | MEDLINE | ID: mdl-36061115

ABSTRACT

The 3D musculoskeletal motion of animals is of interest for various biological studies and can be derived from X-ray fluoroscopy acquisitions by means of image matching or manual landmark annotation and mapping. While the image matching method requires a robust similarity measure (intensity-based) or an expensive computation (tomographic reconstruction-based), the manual annotation method depends on the experience of operators. In this paper, we tackle these challenges by a strategic approach that consists of two building blocks: an automated 3D landmark extraction technique and a deep neural network for 2D landmarks detection. For 3D landmark extraction, we propose a technique based on the shortest voxel coordinate variance to extract the 3D landmarks from the 3D tomographic reconstruction of an object. For 2D landmark detection, we propose a customized ResNet18-based neural network, BoneNet, to automatically detect geometrical landmarks on X-ray fluoroscopy images. With a deeper network architecture in comparison to the original ResNet18 model, BoneNet can extract and propagate feature vectors for accurate 2D landmark inference. The 3D poses of the animal are then reconstructed by aligning the extracted 2D landmarks from X-ray radiographs and the corresponding 3D landmarks in a 3D object reference model. Our proposed method is validated on X-ray images, simulated from a real piglet hindlimb 3D computed tomography scan and does not require manual annotation of landmark positions. The simulation results show that BoneNet is able to accurately detect the 2D landmarks in simulated, noisy 2D X-ray images, resulting in promising rigid and articulated parameter estimations.

5.
Chem Sci ; 13(30): 8759-8765, 2022 Aug 04.
Article in English | MEDLINE | ID: mdl-35975149

ABSTRACT

Herein, we report a novel fluorous-tag assisted two-directional oligosaccharide assembly strategy, which maintained the high coupling efficiency of solution-phase synthesis and featured the advantage of an easy purification process comparable to solid-phase synthesis. A well-designed fluorous tag was decorated on the latent anomeric leaving group in interrupted Pummerer reaction mediated (IPRm) glycosylation. The high efficiency of the in-solution phase glycosylation and the unique affinity of the fluorous tag towards polytetrafluoroethylene (PTFE) particles allowed flexible assembly from the reducing end to the non-reducing end and fast purification by PTFE-assisted filtration. Moreover, the fluorous-tagged latent anomeric leaving group could be activated by oxidation and cleaved by IPRm glycosylation, thus enabling the elongation of the carbohydrate chain from the non-reducing end to the reducing end as well as the recovery of the fluorous tag. The present two-directional synthetic strategy is used to assemble the repeating unit of Streptococcus pneumoniae type 14 capsular polysaccharide.

6.
Nano Lett ; 22(12): 4661-4668, 2022 Jun 22.
Article in English | MEDLINE | ID: mdl-35640103

ABSTRACT

Confined nanospaces provide a new platform to promote catalytic reactions. However, the mechanism of catalytic enhancement in the nanospace still requires insightful exploration due to the lack of direct visualization. Here, we report operando investigations on the etching and growth of graphene in a two-dimensional (2D) confined space between graphene and a Cu substrate. We observed that the graphene layer between the Cu and top graphene layer was surprisingly very active in etching (more than 10 times faster than the etching of the top graphene layer). More strikingly, at a relatively low temperature (∼530 °C), the etched carbon radicals dissociated from the bottom layer, in turn feeding the growth of the top graphene layer with a very high efficiency. Our findings reveal the in situ dynamics of the anomalous confined catalytic processes in 2D confined spaces and thus pave the way for the design of high-efficiency catalysts.

7.
Nat Nanotechnol ; 17(1): 33-38, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34782776

ABSTRACT

The growth of wafer-scale single-crystal two-dimensional transition metal dichalcogenides (TMDs) on insulating substrates is critically important for a variety of high-end applications1-4. Although the epitaxial growth of wafer-scale graphene and hexagonal boron nitride on metal surfaces has been reported5-8, these techniques are not applicable for growing TMDs on insulating substrates because of substantial differences in growth kinetics. Thus, despite great efforts9-20, the direct growth of wafer-scale single-crystal TMDs on insulating substrates is yet to be realized. Here we report the successful epitaxial growth of two-inch single-crystal WS2 monolayer films on vicinal a-plane sapphire surfaces. In-depth characterizations and theoretical calculations reveal that the epitaxy is driven by a dual-coupling-guided mechanism, where the sapphire plane-WS2 interaction leads to two preferred antiparallel orientations of the WS2 crystal, and sapphire step edge-WS2 interaction breaks the symmetry of the antiparallel orientations. These two interactions result in the unidirectional alignment of nearly all the WS2 islands. The unidirectional alignment and seamless stitching of WS2 islands are illustrated via multiscale characterization techniques; the high quality of WS2 monolayers is further evidenced by a photoluminescent circular helicity of ~55%, comparable to that of exfoliated WS2 flakes. Our findings offer the opportunity to boost the production of wafer-scale single crystals of a broad range of two-dimensional materials on insulators, paving the way to applications in integrated devices.

8.
Opt Express ; 29(3): 3438-3457, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33770942

ABSTRACT

Laboratory based X-ray micro-CT is a non-destructive testing method that enables three dimensional visualization and analysis of the internal and external morphology of samples. Although a wide variety of commercial scanners exist, most of them are limited in the number of degrees of freedom to position the source and detector with respect to the object to be scanned. Hence, they are less suited for industrial X-ray imaging settings that require advanced scanning modes, such as laminography, conveyor belt scanning, or time-resolved imaging (4DCT). We introduce a new X-ray scanner FleXCT that consists of a total of ten motorized axes, which allow a wide range of non-standard XCT scans such as tiled and off-centre scans, laminography, helical tomography, conveyor belt, dynamic zooming, and X-ray phase contrast imaging. Additionally, a new software tool 'FlexRayTools' was created that enables reconstruction of non-standard XCT projection data of the FleXCT instrument using the ASTRA Toolbox, a highly efficient and open source set of tools for tomographic projection and reconstruction.

9.
BMC Surg ; 20(1): 312, 2020 Dec 02.
Article in English | MEDLINE | ID: mdl-33267803

ABSTRACT

BACKGROUND: The common complications of radical hysterectomy and pelvic lymphadenectomy usually include wound infection, hemorrhage or hematomas, lymphocele, uretheral injury, ileus and incisional hernias. However, internal hernia secondary to the orifice associated with the uncovered vessels after pelvic lymphadenectomy is very rare. CASE PRESENTATION: We report a case of internal hernia with intestinal perforation beneath the superior vesical artery that occurred one month after laparoscopic pelvic lymphadenectomy for cervical cancer. A partial ileum resection was performed and the right superior vesical artery was transected to prevent recurrence of the internal hernia. CONCLUSIONS: Retroperitonealization after the pelvic lymphadenectomy should be considered in patients with tortuous, elongated arteries which could be causal lesions of an internal hernia.


Subject(s)
Hysterectomy/adverse effects , Internal Hernia/etiology , Laparoscopy/adverse effects , Lymph Node Excision/adverse effects , Uterine Cervical Neoplasms/surgery , Female , Herniorrhaphy , Humans , Iliac Artery , Intestinal Perforation/etiology , Intestinal Perforation/surgery , Male , Neoplasm Recurrence, Local , Postoperative Complications , Treatment Outcome , Umbilical Arteries
10.
J Gene Med ; 22(7): e3179, 2020 07.
Article in English | MEDLINE | ID: mdl-32119160

ABSTRACT

BACKGROUND: The present study aimed to investigated the expression pattern of long noncoding RNA LINC00858 (LINC00858) in gastric cancer (GC) patients and its feasibility as a new prognostic biomarker. METHODS: We examined LINC00858 expression in GC tissues and matched normal tissues from 189 patients using a quantitative reverse transcription-polymerase chain reaction. The correlations of LINC00858 levels in GC patients with clinicopathologic features were analyzed using a chi-squared test. The influence of LINC00858 on the overall survival rate of GC patients was precisely calculated using Kaplan-Meier methods (log rank tests). Multivariate Cox regression assays were carried out for the identification of the independent risk factors for GC. RESULTS: We observed that LINC00858 was distinctly up-regulated in GC tissues compared to adjacent non-tumor specimens (p < 0.01). Higher expression of LINC00858 in GC was found to be associated with TNM stage (p = 0.003) and lymphatic metastasis (p = 0.007). Using Kaplan-Meier assays, we found that patients with high expression levels of LINC00858 had a distinctly poor overall survival and disease-free survival compared to those with low expression levels of LINC00858 (p = 0.0102). Multivariate analyses confirmed that LINC00858 (p < 0.05) was an independent prognosis factor for GC patients. CONCLUSIONS: The data obtained in our study indicate that LINC00858 may be used as a novel prognostic indicator in GC patients.


Subject(s)
RNA, Long Noncoding/genetics , Stomach Neoplasms/genetics , Up-Regulation , Biomarkers, Tumor/genetics , Disease Progression , Female , Gene Expression Regulation, Neoplastic , Humans , Lymphatic Metastasis/genetics , Male , Middle Aged , Neoplasm Staging , Prognosis , Real-Time Polymerase Chain Reaction , Stomach Neoplasms/diagnosis
11.
Bioengineered ; 11(1): 70-80, 2020 12.
Article in English | MEDLINE | ID: mdl-31884893

ABSTRACT

Non-small-cell lung cancer (NSCLC) is the main pathological type of lung cancer and has a low overall five-year survival rate. miR-187 has been reported to play major roles in various tumor types. In this study, we explored the impact of miR-187 on NSCLC. qRT-PCR results demonstrated that miR-187 expression is lower in NSCLC and cancer cells than normal tissues and normal lung cells. miR-187 expression levels are associated with tumor size, TNM stage and overall survival rate. MTS and colony formation assays showed that high miR-187 expression inhibits NSCLC cell proliferation and colony formation ability, and flow cytometry showed that miR-187 overexpression induces cell cycle arrest at the G0/G1 phase. A luciferase reporter assay showed that FGF9 is a target of miR-187. miR-187 overexpression reduces the expression of FGF9, cyclin D1 CDK4 and CDK6. Therefore, miR-187 may present a new NSCLC treatment target by regulates cyclins-related protein expression.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Cell Proliferation , Fibroblast Growth Factor 9/genetics , Lung Neoplasms/genetics , MicroRNAs/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/physiopathology , Cell Line, Tumor , Cyclin D1/genetics , Cyclin D1/metabolism , Cyclin-Dependent Kinase 6/genetics , Cyclin-Dependent Kinase 6/metabolism , Fibroblast Growth Factor 9/metabolism , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/physiopathology , MicroRNAs/metabolism
12.
Zhonghua Wei Chang Wai Ke Za Zhi ; 21(7): 814-818, 2018 Jul 25.
Article in Chinese | MEDLINE | ID: mdl-30051452

ABSTRACT

OBJECTIVE: To examine the association between the genotype (LL, LS and SS) of serotonin transporter promoter gene polymorphism(5-HTTLPR) and clinicopathological factors, and to investigate the effect of 5-HTTLPR on the prognosis of colorectal cancer patients. METHODS: Data of peripheral blood samples of 161 colorectal cancer patients at the Second Affiliated Hospital of Guangzhou Medical University from October 2009 to January 2014 were collected retrospectively. The genotyping of 5-HTTLPR was determined by PCR and agarose gel electrophoresis. Coincidence Chi-square test was used to examine the 5-HTTLPR genotype with Hardy-Weinberg law. Chi-square test and Cox multifactor model were used to analyze the association of 5-HTTLPR genotype with clinicopathology and prognosis. All the patients were informed and agreed to participate in the study. This study was approved by the Hospital Ethics Committee (2015056). RESULTS: Of 161 colorectal cancer patients, 89 were male and 72 were female; the median age was 64 (25-85) years; 86 (53.5%) cases were colon cancer and 75 (46.5%) were rectal cancer. Genotype was LL in 12 cases, LS in 59 cases and SS in 90 cases, which complied with the law of Hardy-Weinberg genetic balance (χ²=0.288, P=0.592). Univariate analysis showed that 5-HTTLPR gene polymorphism was only associated with lymph node metastasis [lymph node metastasis rate: LL and LS genotype 21.1% (15/71);SS genotype 40.0% (36/90), χ²= 6.532, P=0.011]. The 3-year and 5-year overall survival rates of whole patients were 71% and 63% respectively. Multivariate analysis revealed that the SS genotype was an independent risk factor affecting the overall survival of colorectal cancer patients(HR=1.933, 95%CI:1.090-3.428, P=0.024). CONCLUSION: Among genotypes of 5-HTTLPR gene, colorectal cancer patients with SS genotype have higher risk of lymph node metastasis and poorer prognosis.


Subject(s)
Colorectal Neoplasms/genetics , Genotype , Serotonin Plasma Membrane Transport Proteins/genetics , Adult , Aged , Aged, 80 and over , Colorectal Neoplasms/pathology , Female , Humans , Male , Middle Aged , Polymorphism, Genetic , Prognosis , Retrospective Studies
13.
Cancer Biomark ; 20(4): 627-635, 2017 Dec 06.
Article in English | MEDLINE | ID: mdl-28800321

ABSTRACT

BACKGROUND AND OBJECTIVE: The association of chemotherapy-associated hemoglobin and survival of colorectal cancer (CRC) receiving adjuvant chemotherapy is uncertain. We sought to explore the prognostic value of chemotherapy-associated hemoglobin in CRC receiving adjuvant chemotherapy and the best cut point affecting prognosis. METHODS: Three hundred and twenty stage II and III CRC patients receiving adjuvant FOLFOX chemotherapy from March 2003 to March 2012 were enrolled. The associations between chemotherapy-associated hemoglobin (the absolute levels of post-chemotherapy) or chemotherapy-associated hemoglobin change (change between the pre- and post-chemotherapy hemoglobins) and disease free survival (DFS) or overall survival (OS) of CRC, and the best cut point were investigated. RESULTS: Log rank test showed the best cut points for chemotherapy-associated hemoglobin and chemotherapy-associated hemoglobin change were respectively 90 g/L, 30 g/L. Cox regression model showed chemotherapy-associated hemoglobin < 90 g/L was the independent prognostic factor for DFS (HR, 2.221; 95% CI = 1.157-4.262), OS (HR, 2.058; 95% CI = 1.009-4.197), respectively, but no association of chemotherapy-associated hemoglobin change ⩾ 30g/L and DFS (HR, 2.063; 95% CI = 0.929-4.583), OS (HR, 1.386; 95% CI = 0.553-3.471) was found. CONCLUSIONS: Chemotherapy-associated hemoglobin < 90 g/L has a significant prognostic value in CRC receiving adjuvant chemotherapy, which is a significant biomarker in the individualized management and may suggest the simple indication for the treatment of anemia in adjuvant chemotherapy in CRC.


Subject(s)
Colorectal Neoplasms/blood , Colorectal Neoplasms/mortality , Hemoglobins , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers , Chemotherapy, Adjuvant , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Erythrocyte Indices , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Staging , Prognosis , Young Adult
14.
J Breast Cancer ; 19(3): 231-241, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27721872

ABSTRACT

PURPOSE: Cell-in-cell structures are created by one living cell entering another homotypic or heterotypic living cell, which usually leads to the death of the internalized cell, specifically through caspase-dependent cell death (emperitosis) or lysosome-dependent cell death (entosis). Although entosis has attracted great attention, its occurrence is controversial, because one cell line used in its study (MCF-7) is deficient in caspase-3. METHODS: We investigated this issue using MCF-7 and A431 cell lines, which often display cell-in-cell invasion, and have different levels of caspase-3 expression. Cell-in-cell death morphology, microstructures, and signaling pathways were compared in the two cell lines. RESULTS: Our results confirmed that MCF-7 cells are caspase-3 deficient with a partial deletion in the CASP-3 gene. These cells underwent cell death that lacked typical apoptotic properties after staurosporine treatment, whereas caspase-3-sufficient A431 cells displayed typical apoptosis. The presence of caspase-3 was related neither to the lysosome-dependent nor to the caspase-dependent cell-in-cell death pathway. However, the existence of caspase-3 was associated with a switch from lysosome-dependent cell-in-cell death to the apoptotic cell-in-cell death pathway during entosis. Moreover, cellular hypoxia, mitochondrial swelling, release of cytochrome C, and autophagy were observed in internalized cells during entosis. CONCLUSION: The occurrence of caspase-independent entosis is not a cell-specific process. In addition, entosis actually represents a cellular self-repair system, functioning through autophagy, to degrade damaged mitochondria resulting from cellular hypoxia in cell-in-cell structures. However, sustained autophagy-associated signal activation, without reduction in cellular hypoxia, eventually leads to lysosome-dependent intracellular cell death.

15.
Med Phys ; 43(3): 1563-75, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26936739

ABSTRACT

PURPOSE: Mathematical model observers commonly used for diagnostic image-quality assessments in x-ray imaging research are generally constrained to relatively simple detection tasks due to their need for statistical prior information. Visual-search (VS) model observers that employ morphological features in sequential search and analysis stages have less need for such information and fewer task constraints. The authors compared four VS observers against human observers and an existing scanning model observer in a pilot study that quantified how mass detection and localization in simulated digital breast tomosynthesis (DBT) can be affected by the number P of acquired projections. METHODS: Digital breast phantoms with embedded spherical masses provided single-target cases for a localization receiver operating characteristic (LROC) study. DBT projection sets based on an acquisition arc of 60° were generated for values of P between 3 and 51. DBT volumes were reconstructed using filtered backprojection with a constant 3D Butterworth postfilter; extracted 2D slices were used as test images. Three imaging physicists participated as observers. A scanning channelized nonprewhitening (CNPW) observer had knowledge of the mean lesion-absent images. The VS observers computed an initial single-feature search statistic that identified candidate locations as local maxima of either a template matched-filter (MF) image or a gradient-template MF (GMF) image. Search inefficiencies that modified the statistic were also considered. Subsequent VS candidate analyses were carried out with (i) the CNPW statistical discriminant and (ii) the discriminant computed from GMF training images. These location-invariant discriminants did not utilize covariance information. All observers read 36 training images and 108 study images per P value. Performance was scored in terms of area under the LROC curve. RESULTS: Average human-observer performance was stable for P between 7 and 35. In the absence of search inefficiencies, the VS models based on the GMF analysis provided the best correlation (Pearson ρ ≥ 0.62) with the human results. The CNPW-based VS observers deviated from the humans primarily at lower values of P. In this limited study, search inefficiencies allowed for good quantitative agreement with the humans for most of the VS observers. CONCLUSIONS: The computationally efficient training requirements for the VS observer are suitable for high-resolution imaging, indicating that the observer framework has the potential to overcome important task limitations of current model observers for x-ray applications.


Subject(s)
Mammography/methods , Radiographic Image Enhancement/methods , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Observer Variation , Phantoms, Imaging , Quality Control , ROC Curve
16.
Zhonghua Wei Chang Wai Ke Za Zhi ; 18(12): 1261-4, 2015 Dec.
Article in Chinese | MEDLINE | ID: mdl-26704012

ABSTRACT

OBJECTIVE: To analyze the impact of platelet count on the prognosis of stage II-III colorectal cancer receiving adjuvant chemotherapy. METHODS: Clinical and follow-up data of 286 patients with stage II-III colorectal cancer receiving adjuvant FOLFOX chemotherapy from March 2003 to October 2011 were analyzed retrospectively. Associations of baseline blood platelet count before chemotherapy and nadir blood platelet count during chemotherapy with relapse and death after adjuvant chemotherapy were analyzed by ROC curve and the optimal cutoff was selected. The association of the blood platelet count and the prognosis was analyzed by Kaplan-Meier and Cox regression model. RESULTS: ROC curve showed the baseline blood platelet count was associated with recurrence (AUC=0.588, P=0.034). The optimal cutoff affecting recurrence was 276×10(9)/L. Kaplan-Meier showed those with baseline platelet count >276×10(9)/L receiving adjuvant chemotherapy had worse disease free survival (DFS) than those with baseline platelet count ≤276×10(9)/L, whose 5-year disease free survival(DFS) was 66% and 80% respectively (P=0.013). Cox regression analysis revealed baseline platelet count >276×10(9)/L was an independent unfavorable factor for DFS of adjuvant chemotherapy in colorectal cancer (HR=1.865, 95% CI: 1.108-3.141, P=0.019). CONCLUSION: Colorectal cancer patients receiving adjuvant chemotherapy with baseline platelet count >276×10(9)/L have worse prognosis.


Subject(s)
Colonic Neoplasms , Platelet Count , Antineoplastic Combined Chemotherapy Protocols , Chemotherapy, Adjuvant , Colorectal Neoplasms , Disease-Free Survival , Fluorouracil , Humans , Leucovorin , Neoplasm Staging , Organoplatinum Compounds , Prognosis , Recurrence , Retrospective Studies
17.
Opt Lett ; 39(21): 6343-6, 2014 Nov 01.
Article in English | MEDLINE | ID: mdl-25361350

ABSTRACT

In this Letter, we propose the first single-shot, noninterferometric x-ray imaging method for simultaneous retrieval of absorption, phase, and differential-phase imagery with quantitative accuracy. Our method utilizes a photon-counting spectral x-ray detector in conjunction with a simplified transport-of-intensity equation for coded-aperture phase-contrast imaging to efficiently solve the retrieval problem. This method can utilize an incoherent and polychromatic (clinical or laboratory) x-ray tube and can enable retrieval for a wide range and composition of material properties. The proposed method has been validated via computer simulations and is expected to significantly benefit applications that are sensitive to complexity of measurement, radiation dose and imaging time.


Subject(s)
Absorption, Radiation , Optical Imaging/methods , X-Rays
18.
Opt Lett ; 39(18): 5395-8, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-26466281

ABSTRACT

Transport-of-intensity equations (TIEs) allow better understanding of image formation and assist in simplifying the "phase problem" associated with phase-sensitive x-ray measurements. In this Letter, we present for the first time to our knowledge a simplified form of TIE that models x-ray differential phase-contrast (DPC) imaging with coded-aperture (CA) geometry. The validity of our approximation is demonstrated through comparison with an exact TIE in numerical simulations. The relative contributions of absorption, phase, and differential phase to the acquired phase-sensitive intensity images are made readily apparent with the approximate TIE, which may prove useful for solving the inverse phase-retrieval problem associated with these CA geometry based DPC.

19.
Water Res ; 50: 350-8, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24210505

ABSTRACT

Silver nanoparticles (nanosilver or AgNPs) have excellent antimicrobial properties. Because of their increasing use, there is a concern about the potential impact of AgNPs in wastewater treatment systems. This study investigated the long-term effects of AgNPs (continuous loading for more than 60 days) on membrane bioreactor (MBR) activated sludge performance. At the influent AgNP concentration of 0.10 mg Ag/L, there was no significant difference in effluent water quality or bacterial activities before and after AgNP exposure. Nitrifying bacterial community structure was relatively stable before and after the long-term AgNP loading. Both ammonia-oxidizing bacteria (AOB) Nitrosomonas spp. and Nitrosospira spp. were present while Nitrospira spp. was the dominant nitrite-oxidizing bacterial species throughout this study. Abundance of silver resistance gene silE in the MBR, however, increased by 50-fold 41 days after the AgNP exposure, and then decreased with continuous AgNP exposure. The long-term nanosilver exposure did not change the membrane fouling rate although extracellular polymeric substances (EPS) concentration increased significantly after nanosilver dosing. The results suggest that AgNPs at the influent concentrations of 0.10 mg/L and below have almost no impact on activated sludge wastewater treatment performance, as activated sludge can effectively reduce nanosilver toxicity by adsorbing or precipitating AgNPs and silver ions (Ag(+)) released from the dissolution of AgNPs.


Subject(s)
Bacteria/drug effects , Bioreactors/microbiology , Membranes, Artificial , Metal Nanoparticles/chemistry , Sewage/microbiology , Silver/pharmacology , Aerobiosis/drug effects , Ammonia/metabolism , Autotrophic Processes/drug effects , Bacteria/metabolism , Biopolymers/analysis , Heterotrophic Processes/drug effects , Nitrification/drug effects , Nitrogen/analysis , Oxidation-Reduction/drug effects , Polymorphism, Restriction Fragment Length , Pressure , Silver/analysis , Time Factors , Waste Disposal, Fluid , Water Quality
20.
Water Environ Res ; 83(8): 722-30, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21905409

ABSTRACT

Efficient nutrient removal in decentralized wastewater treatment systems is a challenging task. To improve the removal of organic matter and nitrogen from wastewater, two types of bioreactors using membrane-aerated biofilm reactor (MABR) and microbial fuel cell (MFC) techniques were evaluated. During more than 250 days of continuous-flow reactor operation, both reactors showed consistently high chemical oxygen demand removal (>86%). At an influent ammonium-nitrogen (NH4(+)-N) concentration of 30 mg N/L, the average effluent NH4(+)-N concentrations were 6.2 and 0.5 mg N/L for the MABR and MFC reactor, respectively, while the effluent nitrate-nitrogen (NO3(-)-N) concentrations were 5.4 mg/ L in the MABR and 19.2 mg/L in the MFC-based reactor. The overall total inorganic nitrogen removal efficiencies were 64% and 36% for the MABR and MFC reactor, respectively. At the measured dissolved oxygen concentrations of 5.2 and 0.23 mg/L in the aerobic/anoxic zone of the MFC and MABR, respectively, a specific oxygen uptake rate of 0.1 g O2/g VSS-d, resulting from ammonia oxidation, was detected in the settled sludge of the MFC, while no nitrifying activity of the sludge from the MABR was detected. Molecular microbial analysis demonstrated a link between the bacterial community structure and nitrifying activity. The relatively high abundance of Nitrosomonas europaea was associated with its detectable nitrification activity in the settled sludge of the MFC. The results suggest that MABR and MFC techniques have the potential to improve organic and nitrogen removal in decentralized wastewater systems.


Subject(s)
Bacteria/classification , Bioreactors , Nitrogen/metabolism , Waste Disposal, Fluid/methods , Water Purification/methods , Bacteria/isolation & purification , Bacteria/metabolism , Bacterial Physiological Phenomena , Biodegradation, Environmental , Biodiversity , Bioelectric Energy Sources , Biofilms , Biological Oxygen Demand Analysis , Nitrosomonas europaea/metabolism , Quaternary Ammonium Compounds/metabolism , Sewage/chemistry , Sewage/microbiology
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