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Using a combination of static precompression and laser-driven shock compression, shock temperature and reflectivity of H2O have been measured up to 350 GPa and 2.1 × 104 K. Here, two calibration standards were applied to enhance temperature measurement reliability. Additionally, in temperature calculations, the discrepancy in reflectivity between active probe beam wavelength and self-emission wavelength has been taken into account to improve the data’s precision. Precompressed water’s temperature–pressure data are in very good agreement with our quantum molecular dynamics model, suggesting a superionic conductor of H2O in the icy planets’ deep interior. A sluggish slope gradually approaching Dulong–Petit limit at high temperature was found at a specific heat capacity. Also, high reflectivity and conductivity were observed at the same state. By analyzing the temperature–pressure diagram, reflectivity, conductivity and specific heat comprehensively at conditions simulating the interior of planets in this work, we found that as the pressure rises, a change in ionization appears; it is supposedly attributed to energetics of bond-breaking in the H2O as it transforms from a bonded molecular fluid to an ionic state. Such molecular dissociation in H2O is associated with the conducting transition because the dissociated hydrogen atoms contribute to electrical properties. [ABSTRACT FROM AUTHOR]

We calculated the harmonic spectra generated from the asymmetric molecules of HD and HeH. It is found that HDproduces only odd harmonics, while HeH produces both odd and even harmonics. Further analysis reveals that for both HD and HeH, the nuclear dipole acceleration can generate even harmonics, but it is three orders of magnitude lower than that of the electron. Hence, the electronic dipole acceleration dominates the harmonic generation. For HD, the electronic dipole acceleration only contributes to the generation of odd harmonics, but for HeH it contributes to the generation of both odd and even harmonics. Besides, one concept of the broken degree of system-symmetry is proposed to explain the different odd-even property between the harmonic spectra of HD and HeH. [ABSTRACT FROM AUTHOR]

The wavelength dependence of electron localization of and its isotopomers in the ultraviolet pump-probe scheme is investigated by numerically solving the time-dependent Schrödinger equation. By combining with a semiclassical method, an effective analytical formula expressed in the adiabatic representation is established to describe the localization probability with several zero crossings. A stable zone with respect to the laser intensity and carrier envelope phase is found at a relatively long probe wavelength. Finally, the critical probe wavelengths to reach at the stable zone are derived by using the three-dimensional model. Slower nuclear motion of heavier isotopomers leads to a longer critical wavelength. [ABSTRACT FROM AUTHOR]

In the title compound, C19H15Cl4NO3, the isoindole unit is planar and the oxazino ring adopts a twist-boat conformation. The dihedral angle between the isoindole unit and the phenyl ring is 50.46 (13)°. The molecules are linked via intermolecular O—H...O hydrogen bonds and weak C—H...O and C—H...Cl interactions, forming a three-dimensional network. [ABSTRACT FROM AUTHOR]

The title compound, C5H15NO6P2, exists as a zwitterion. The N atom of the amino group is protonated and one of the phospho­nic acid groups is deprotonated. The mol­ecules form hydrogen-bonded (202) layers. [ABSTRACT FROM AUTHOR]

As the most common histological subtype of primary lung cancer, lung adenocarcinoma (LUAD) causes enormous cancer deaths worldwide. Radiotherapy has been frequently used in LUAD cases, and radiosensitivity is vital for LUAD therapy. This research sought to explore the genetic factors affecting radiosensitivity in LUAD and inner mechanisms. LINC00511, miR-497-5p, and SMAD3 expression in LUAD cells were detected via qRT-PCR and western blot. CCK-8 assays, colony formation, and flow cytometry assays were employed to explore the cell viability, apoptosis, and radiosensitivity in PC-9 and A549 cells. The targeting relationship between LINC00511, miR-497-5p, and SMAD3 was verified by dual luciferase reporter assay. Furthermore, xenograft experiments were performed for the in vivo verification. In conclusion, LINC00511 was overexpressed in LUAD cells, which downregulated downstream miR-497-5p expression and mediately led to SMAD3 activation. LINC00511 downregulation suppressed cell viability while enhanced apoptosis rate in LUAD cells. Also, LINC00511 and SMAD3 were overexpressed, while miR-497-5p was downregulated in LUAD cells exposed to 4Gy irradiation treatment. Moreover, LINC00511 inhibition could block SMAD3 expression and promoted the radiosensitivity both in vitro and in vivo. These findings uncover LINC00511 knockdown promoted miR-497-5p expression and subsequently led to lower SMAD3 level, which enhanced radiosensitivity in LUAD cells. LINC00511/miR-497-5p/SMAD3 axis could be of considerable potential to enhance radiosensitivity in LUAD. [ABSTRACT FROM AUTHOR]

Since the outbreak, COVID-19 has spread rapidly across the globe due to its high infectivity and lethality. Age appears to be one of the key factors influencing the status and progression of SARS-CoV-2 infection, as multiple reports indicated that the majority of COVID-19 infections and severe cases are elderly. Most people simply assume that the elderly are more susceptible to SARS-CoV-2 than the young, but the mechanism behind it is still open to question. The older and younger people are at similar risk of infection because their infection process is the same and they must be exposed to the virus first. However, whether they will get sick after exposure to the virus and how their disease progresses depend on their immune mechanisms. In older populations, inflammation and immune aging reduce their ability to resist SARS-CoV-2 infection. Meanwhile, under the influence of comorbidities, ACE2 receptor and various cytokines undergo corresponding changes, thus accelerating the entry, replication, and transmission of SARS-CoV-2 in the body, promoting disease progression, and leading to severe illness and even death. In addition, the relatively fragile mental state of the elderly can also affect their timely recovery from COVID-19. Therefore, once older people are infected with SARS-CoV-2, they are more prone to severe illness and death with a poor prognosis, and they should strengthen protection to avoid exposure to the virus. [ABSTRACT FROM AUTHOR]

Wild tomatoes (Solanum peruvianum) are important genomic resources for tomato research and breeding. Development of a foreign DNA-free clustered regularly interspaced short palindromic repeat (CRISPR)-Cas delivery system has potential to mitigate public concern about genetically modified organisms. Here, we established a DNA-free CRISPR-Cas9 genome editing system based on an optimized protoplast regeneration protocol of S. peruvianum, an important resource for tomato introgression breeding. We generated mutants for genes involved in small interfering RNAs biogenesis, RNA-DEPENDENT RNA POLYMERASE 6 (SpRDR6), and SUPPRESSOR OF GENE SILENCING 3 (SpSGS3); pathogen-related peptide precursors, PATHOGENESIS-RELATED PROTEIN-1 (SpPR-1) and PROSYSTEMIN (SpProSys); and fungal resistance (MILDEW RESISTANT LOCUS O, SpMlo1) using diploid or tetraploid protoplasts derived from in vitro-grown shoots. The ploidy level of these regenerants was not affected by PEG-Ca2+-mediated transfection, CRISPR reagents, or the target genes. By karyotyping and whole genome sequencing analysis, we confirmed that CRISPR-Cas9 editing did not introduce chromosomal changes or unintended genome editing sites. All mutated genes in both diploid and tetraploid regenerants were heritable in the next generation. spsgs3 null T0 regenerants and sprdr6 null T1 progeny had wiry, sterile phenotypes in both diploid and tetraploid lines. The sterility of the spsgs3 null mutant was partially rescued, and fruits were obtained by grafting to wild-type (WT) stock and pollination with WT pollen. The resulting seeds contained the mutated alleles. Tomato yellow leaf curl virus proliferated at higher levels in spsgs3 and sprdr6 mutants than in the WT. Therefore, this protoplast regeneration technique should greatly facilitate tomato polyploidization and enable the use of CRISPR-Cas for S. peruvianum domestication and tomato breeding. [ABSTRACT FROM AUTHOR]

In addition to the rapid, global spread of SARS-CoV-2, new and comparatively more contagious variants are of considerable concern. These emerging mutations have become a threat to the global public health, creating COVID-19 surges in different countries. However, information on these emerging variants is limited and scattered. In this review, we discuss new variants that have emerged worldwide and identify several variants of concern, such as B.1.1.7, B.1.351, P.1, B.1.617.2 and B.1.1.529, and their basic characteristics. Other significant variants such as C.37, B.1.621, B.1.525, B.1.526, AZ.5, C.1.2, and B.1.617.1 are also discussed. This review highlights the clinical characteristics of these variants, including transmissibility, pathogenicity, susceptible population, and re-infectivity. It provides the latest information on the recent variants of SARS-CoV-2. The summary of this information will help researchers formulate reasonable strategies to curb the ongoing COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Deep learning techniques can automatically learn features from a large number of image data set. Automatic vegetable image classification is the base of many applications. This paper proposed a high performance method for vegetable images classification based on deep learning framework. The AlexNet network model in Caffe was used to train the vegetable image data set. The vegetable image data set was obtained from ImageNet and divided into training data set and test data set. The output function of the AlexNet network adopted the Rectified Linear Units (ReLU) instead of the traditional sigmoid function and the tanh function, which can speed up the training of the deep learning network. The dropout technology was used to improve the generalization of the model. The image data extension method was used to reduce overfitting in the learning process. With AlexNet network model used for training different number of vegetable image data set, the experimental results showed that the classification accuracy decreases as the number of data set decreases. The experimental verification indicated that the accuracy rate of the deep learning method in the test data set reached as high as 92.1%, which was greatly improved compared with BP neural network (78%) and SVM classifier (80.5%) methods. [ABSTRACT FROM AUTHOR]

Two lanthanide mercury complexes were synthesized. They display red or ultraviolet photoluminescence which come from the characteristic emissions of the 4 G 5/2 → 6 H J (J = 7/2, 9/2 and 11/2 of Sm3+ ions) and the 6 P 7/2 → 8 S 7/2 of Gd3+ ions. The CIE chromaticity coordinates are (0.6597, 0.34). The semiconductor bandgaps are 5.01 eV and 2.77 eV. [Display omitted] • It reports two new lanthanide mercury isonicotinic acid complexes. • They display red or ultraviolet photoluminescence. • The photoluminescence come from the emission of 4 G 5/2 → 6 H J and 6 P 7/2 → 8 S 7/2 of lanthanide ions. • The semiconductor bandgaps are 5.01 eV and 2.77 eV. Two new lanthanide mercury isonicotinic acid complexes [Sm(IA) 3 (H 2 O) 2 ] 2 n 2 n (HgCl 4)·3 n Cl·7 n H 3 O·2 n H 2 O (1 ; IA = isonicotinic acid anion) and {[Gd(IA) 3 (H 3 O) 2 ] 2 (Hg 3 Br 8)} n (n HgBr 2)·2 n NO 3 (2 ; IA = isonicotinic acid anion) were synthesized. The crystal structures are characterized by single-crystal X-ray diffraction. Complex 1 is characteristic of a one-dimensional (1-D) chain-like structure, while complex 2 features a two-dimensional (2-D) layer-like structure. The photophysical properties of in solid state have been investigated by photoluminescence and solid-state UV/Vis diffuse reflectance spectra. The photoluminescence reveals that they display red or ultraviolet photoluminescence and, the photoluminescence are resulted from the characteristic emissions of the 4 f electron intrashell transitions of the 4 G 5/2 → 6 H J (J = 7/2, 9/2 and 11/2 of the Sm3+ ions in 1) and the 6 P 7/2 → 8 S 7/2 of the Gd3+ ions in 2. The CIE (Commission Internationale de I'Éclairage) chromaticity coordinates for 1 are (0.6597, 0.34) and its CCT (Correlated Color Temperature) is 12853 K. The solid-state UV/Vis diffuse reflectance spectra reveal that the semiconductor bandgaps are 5.01 eV and 2.77 eV. [ABSTRACT FROM AUTHOR]

The behavioral patterns of crabs affect the quality and quantity of their production. Currently there are no methods to track behavioral patterns using imaging-based algorithms. This study provides a precise pathway tracking method for the research of the relationship between behavioral patterns of crabs and their living environment. The Particle Filter algorithm is an appropriate framework to handle non-Gaussian movement, the biological constraints are used to decrease the computational complexity and improve the accuracy of tracking the crabs' pathways and a biological probe is utilized to determine the area of movement. Then, this newly determined area replaces the entire image frame as the search space to reduce the complexity of the computation. In the resampling step, a traditional Gaussian particle distribution is substituted by a fusiform particle distribution, which better matches the crab's biological motion patterns, to represent the probability of the crab movement. This strategy allows the crab positions to be covered using fewer particles, which is more accurate for analyzing abrupt motion or long-term stationary situations than traditional particle distributions. To determine the robustness and accuracy of the results, 3000 and 12,000 frames were used, respectively. The coverage ratio and accuracy increased by 28.79% and 5.75%, respectively, compared with the color histogram-based particle filter (CHPF) and by 69.57% and 37.66% compared with the fission bootstrap particle filter (FBPF). The experimental results show that the proposed tracking method is feasible and can be used as an efficient tool to get the pathway of crabs under water. [ABSTRACT FROM AUTHOR]

We aimed to improve the outcome of t(8;21) acute myeloid leukemia (AML) in the first complete remission (CR1) by applying risk-directed therapy based on minimal residual disease (MRD) determined by RUNX1/RUNX1T1 transcript levels. Risk-directed therapy included recommending allogeneic hematopoietic stem cell transplantation (allo-HSCT) for high-risk patients and chemotherapy/autologous-HSCT (auto-HSCT) for low-risk patients. Among 116 eligible patients, MRD status after the second consolidation rather than induction or first consolidation could discriminate high-risk relapse patients (P = .001). Allo-HSCT could reduce relapse and improve survival compared with chemotherapy for high-risk patients (cumulative incidence of relapse [CIR]: 22.1% vs 78.9%, P < .0001; disease-free survival [DFS]: 61.7% vs 19.6%, P = .001), whereas chemotherapy/auto-HSCT achieved a low relapse rate (5.3%) and high DFS (94.7%) for low-risk patients. - Multivariate analysis revealed that MRD status and treatment choice were independent prognostic factors for relapse, DFS, and OS. We concluded that MRD status after the second consolidation may be the best timing for treatment choice. MRD-directed risk stratification treatment may improve the outcome of t(8;21) AML in CR1. [ABSTRACT FROM AUTHOR]

The title compound, [Co2(HO3PCH2CH2COO)2(C10H8N2)2(H2O)2], was obtained by a hydrothermal method. Two six-coordinate cobalt(II) ions are linked by two 2-carboxyethylphosphonate ligands, forming a centrosymmetric dimer. The dimers are further interlinked by O—H...O hydrogen bonds and π–π stacking [centroid–centroid distance = 4.2975 (5) Å] to form a three-dimensional supramolecular structure. The compound is isostructural with the analogous zinc(II) complex reported recently [Ying, Li, Chen, Liu & Liu (2007). Acta Cryst. E 63, m555–m557]. [ABSTRACT FROM AUTHOR]

A visible-light-promoted reduction of nitrobenzenes using formate salts as the reductant was developed. A wide range of nitrobenzenes can be converted into aniline products in a transition metal free fashion. Mechanistic studies revealed that radical species (carbon dioxide radical anion and thiol radical) are key intermediates for the transformation. We anticipate that this method will provide a valuable and green strategy for the reduction of nitrobenzenes., (© 2024 Wiley-VCH GmbH.)

Common cuttlefish is mainly distributed in the eastern North Atlantic and the coastal waters of Africa, which is an important fishing target for trawl fisheries and the most important commercial species in the Atlantic sepia family. In this study, based on the cuttlefish samples collected from the west Africa coast in July-August 2015, we measured the outer morphological parameters of 283 cuttlebones. Combined with the age information of cuttlebones, we examined the growth characteristics of cuttlefish of different genders. The results showed that there were significant differences in body length and body weight between different genders. The dominant age group of female and male was both 80-100 days. Among the fitting functions of the outer shape of cuttlebone and the age, the logistic function was the best one. The females' maximum likelihood estimates of the outer morphological parameters of cuttlebone were larger than that of males. The absolute and instantaneous relative growth rates of the cuttlebone length and width of male and female cuttlefish peaked at 110-120 days and 100-110 days, respectively. The age of males and females at first sexual maturity was 111 days and 104 days, respectively. The growth difference between genders might be related to environment.

Objective Many physiological and pathological conditions, including cyanotic congenital heart diseases (CCHD), are accompanied by chronic hypoxia, which might interfere with the transcription process. However, the transcriptome profile in peripheral blood under hypoxia is still unidentified. The present work aimed to explore the transcriptional profile alteration of peripheral blood in chronic hypoxia. Methods The present study used a chronic hypoxia rat model to simulate the hypoxic state of CCHD patients. Two groups of Sprague-Dawley rats ( n =6 per group) were either exposed to hypoxia (10% O 2 ) or normoxia (21% O 2 ) for 3 weeks. Body weight was measured weekly. Peripheral blood was collected and total RNA was extracted for RNA-Seq at the end of the hypoxia treatment. After quality assessment, the library was sequenced by the Illumina Hiseq platform. The differentially expressed genes were screened (false discovery rate<0.05 and fold change>2). The functional annotation analysis and cluster analysis of differentially expressed genes were performed based on the adjusted P -value (padj<0.05). Results Compared with the control group, the body weight of the rats in the hypoxia group was significantly lowered ( P <0.01). RNA-Seq results showed that the transcriptome patterns of the two groups had significant differences. In total, 872 genes were identified as differentially expressed. Among all, 803 genes were down-regulated, while only 69 genes were up-regulated in the hypoxia group. The functional enrichment analysis of the 872 genes showed that multiple biological processes involved, such as porphyrin-containing compound metabolic process, hemoglobin complex and oxygen transporter activity. Conclusions Our study demonstrated the transcriptional profile alteration in peripheral blood of chronic hypoxia rat model. This study provided basic data and directions to further understand the physiological and pathological changes in patients with CCHD.

A green and convenient solid-state method assisted by mechanical energy is employed for the synthesis of boron (B) and nitrogen (N) co-doped porous carbons (B,N-Cs). Glutamic acid (Glu) and boric acid (H 3 BO 3 ) are used as the N-containing carbon precursor and boron source, respectively. This method is easy to perform and proved to be efficient towards co-doping B and N into the carbon matrix with high contents of B (7 atom %) and N (10 atom %). By adjusting the molar ratio of H 3 BO 3 to Glu, the surface chemical states of B and N could be readily modulated. When increasing H 3 BO 3 dosage, the pore size of B,N-Cs could be tuned ranging from micropores to mesopores with a Brunauer-Emmett-Teller (BET) surface area up to 940 m 2  g -1 . Finally, the B,N-Cs were applied as metal-free catalysts for the cycloaddition of CO 2 to epoxides, which outperform the N-doped carbon catalyst (NC-900) and the physically mixed catalyst of NC-900/B 4 C. The enhanced activity is attributed to the cooperative effect between B and N sites. X-ray photoelectron spectroscopy (XPS) analysis reveals that BN 3 in the B,N-Cs serves as a critical active site for the cooperative catalysis., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To study outcomes of concurrent chemoradiotherapy (CCRT) or radiotherapy (RT) alone followed by radical surgery in patients with local advanced cervical cancer., Methods: A retrospective approach was carried out in 174 Chinese patients with International Federation of Obstetricians and Gynaecologists stage IB2-IIIB cervical carcinoma. A total of 121 patients were treated with CCRT, while the remaining 53 patients received RT alone, and the regimen of chemotherapy was weekly cisplatin (40 mg/m2). Pathological response, overall survival (OS), progression-free survival (PFS), and complications were analyzed., Results: The median age was 45 years and the mean primary tumor diameter was 4.8 ± 1.0 cm. Pathological complete response (CR) was achieved in 53 patients (30.5%). The CR rate was relatively higher in the CCRT group (31.4% vs 28.3%, P = 0.724), particularly when tumor diameter was less than 5 cm (38.2% vs 30.8%, P = 0.623). With median follow-up of 24 months, patients with CR had improved 3-year OS (100% vs 83.6%, P = 0.018) and 3-year PFS (93.1% vs 83.2%, P = 0.035) compared to patients with residual disease. CCRT was associated with significantly improved 3-year PFS (92.0% vs 76.5%, P = 0.032) compared to RT alone in patients with tumor diameter less than 5 cm. Thirty-seven patients (21.3%) experienced more than grade 2 toxicity, and one patient (0.6%) developed grade 3 uronephrosis. Data thus indicated that pathologic response, tumor size, and lymph-node involvement were highly correlated with clinical outcomes of the local advanced cervical disease., Conclusion: Preoperative CCRT achieved outcomes superior to RT alone, depending on the pathologic response, tumor size and lymph-node involvement as major prognostic factors.

In the present paper wheat flag leaves were collected during the tasseling period, and then 1 mmol x L(-1) hydrogen peroxide was added to induce oxidative stress on leaves. In comparison, the detached leaves were also kept under drought or darkness condition for 24 h for the same purpose. Following the preparation of chloroplasts, polarization fluorescence spectroscopic method was utilized to measure fluorescence emission spectra and fluorescence excitation spectra of chloroplasts in the case of VV, VH, HV and HH, where V and H is representative of vertical polarization and horizontal polarization, respectively. Gaussian deconvolution was done on emission spectra, and the fitting data revealed that no matter whether Chla or Chlb molecules were excited upon excitation at 436 nm or 475 nm, the ratio of fluorescence peak area at 684 nm and 720 nm, i. e. A684/ A720, tends to increase slightly after oxidative stress. In addition, some useful information was available from polarization excitation spectra, where it was observed that the treatment of oxidative stress gave rise to higher ratio of excitation peak intensity between 436 nm and 475 nm (E436/E475), indicating that Chla made more contribution to PSII fluorescence emission than Chlb did. Simultaneously, the ratio of 475 nm and 600 nm (E475/E600), representing the energy transfer efficiency from Car to Chlb, was also found to be higher after the detached leaves were treated. In addition, both fluorescence polarization and viscosity were calculated in this paper, and the data showed that oxidative stress should be responsible for higher fluorescence polarization at 680 nm and higher viscosity in microenviroment. The above-mentioned phenomenon is consistent with the lipid peroxidation of unsaturated fatty acids. It also provides a simple and feasible method to study oxidative stress.

Objective: To explore a method for the treatment of the skin defects at the distal phalanges of 2-5th fingers., Methods: The island flap at the dorsum of the middle phalange was designed with the pedicle of dorsal branches from the digital proper artery. When the flap was used to repair defect at finger pulp, the dorsal branch of the digital proper nerve in the flap was kept to be anastomosed to the digital proper nerve at the recipient finger. From Feb. 2005 to May. 2010, 54 cases with skin defects at the distal phalanges of 61 fingers were treated with the flap, including 35 defects at finger pulp and 26 defects at finger tip., Results: The maximum size of defects and flaps was 2.2 cm x 2.5 cm and 2.4 cm x 2.7 cm, respectively. 61 flaps survived completely. Blister was happened in 3 flaps 2 days after operation, which healed spontaneously without necrosis. 54 cases were followed up for 5 to 22 months (average, 11 months). The flaps had good texture and color match with normal sensation (grade S4). The 2-point discrimination distance was 6-9 mm. The interphalangeal joint had normal movement., Conclusions: The island flap at the dorsum of the middle phalange is an ideal method for the skin defect at the distal phalange of finger.

The objective of study was to observe the efficacy and adverse events of modified CAG regimen in treating patients with relapsed acute myeloid leukemia. CAG regimen with prolongation of aclarubicin up to 7 days were used to treat 17 cases of relapsed acute myeloid. After 1 course of chemotherapy, the efficacy and adverse events were evaluated, patients who did not achieve remission were excluded from this regimen, patients who achieved remission were continuously given 1 course of CAG regimen. The results showed that out of 17 case 8 patients achieved complete remission (CR, 47.06%) and 5 patients achieved partial remission (PR, 29.14%). Most of these cases had slight adverse events which mainly were marrow suppression that could be tolerated, overall survival was 76.47%. In conclusion, treatment for relapsed acute myeloid leukemia with modified CAG regiment is safe and effective, and can provide conditions for allo-hematopoietic stem cell transplantation, but its long term efficacy needs to further study.

The title complex, [Mn(C(6)H(5)N(2)O(4))(2)(H(2)O)(2)], was obtained by hydro-thermal synthesis. The Mn(II) atom, which lies on an inversion centre, displays a slightly distorted octa-hedral geometry. In the crystal packing, complex mol-ecules are linked by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds to form a three-dimensional supramolecular structure. The title complex is isostructural with the corresponding cadmium(II) complex [Nie, Wen, Wu, Liu & Liu (2007 ▶). Acta Cryst. E63, m753-m755].

Computed tomography of diffraction enhanced imaging (DEI-CT) is a novel x-ray phase-contrast computed tomography which is applied to inspect weakly absorbing low-Z samples. Refraction-angle images which are extracted from a series of raw DEI images measured in different positions of the rocking curve of the analyser can be regarded as projections of DEI-CT. Based on them, the distribution of refractive index decrement in the sample can be reconstructed according to the principles of CT. How to combine extraction methods and reconstruction algorithms to obtain the most accurate reconstructed results is investigated in detail in this paper. Two kinds of comparison, the comparison of different extraction methods and the comparison between "two-step" algorithms and the Hilbert filtered backprojection (HFBP) algorithm, draw the conclusion that the HFBP algorithm based on the maximum refraction-angle (MRA) method may be the best combination at present. Though all current extraction methods including the MRA method are approximate methods and cannot calculate very large refraction-angle values, the HFBP algorithm based on the MRA method is able to provide quite acceptable estimations of the distribution of refractive index decrement of the sample. The conclusion is proved by the experimental results at the Beijing Synchrotron Radiation Facility.

Objective: To study the therapeutic effect of collapsed and comminuted distal radius fracture., Methods: Twenty-six patients with collapsed and comminuted distal radius fracture were hospitalized from July 1998 to June 2003. All fractures were treated by the methods of open reduction, sustained bone grafting and passing joint external fixator to restore the anatomic shape of distal radius., Results: All 26 cases were followed up, and the results showed that the fractures have been united radiographically. The joint surfaces were intact and there was no length discrepancy occurred in patient's radius. The average volar tilt was 6 to 15 degrees and the average ulnar tilt was 18 to 25 degrees. According to the Dieust criterion, 19 cases were rated as excellent and 7 as good., Conclusions: The method that applying passing joint external fixator and bone grafting for the treatment of collapsed and comminuted distal radius fracture could maintain the stability of fracture and restore the length of radius and the intact of joint surface.

To investigate the clinical features and outcome of severe pneumonia after allogeneic hematopoietic stem cell transplantation for malignant hematological disease, the clinical features of severe pneumonia, including symptoms, signs, blood-gas analysis and thoracic X-ray change were observed, the clinical therapeutical outcome is also evaluated. The results showed that after treatment with antibiotics or antibiotics + antiviral drugs or antibiotics + antiviral drugs + glucocorticosteroids, as well as mechanical ventilation, pulmonary changes in 17 patients with sever pneumonia completely disappeared, 1 case died. In conclusion, early diagnosis and proper treatment for complicated pneumonia after allogeneic hematopoietic stem cell transplantation can decrease the mortality.

Aim: To establish a luciferase reporter cell line that responds dioxin-like chemicals (DLCs) and on this basis to evaluate its characteristics and application in the determination of DLCs., Methods: A recombinant luciferase reporter plasmid was constructed by inserting dioxin-responsive element (DREs) and MMTV promoter segments into the pGL(3)-promoter plasmid immediately upstream of the luciferase gene, which was structurally demonstrated by fragment mapping analysis in gel electrophoresis and transfected into the human hepatoma cell line HepG(2), both transiently and stably, to identify the inducible expression of luciferase by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD). The time course, responsive period, sensitivity, structure-inducibility and dose-effect relationships of inducible luciferase expression to DLCs was dynamically observed in HepG(2) cells stably transfected by the recombinant vector (HepG(2)-Luc) and compared with that assayed by ethoxyresorufin-O-deethylase (EROD) in non-transfected HepG(2) cells (HepG(2)-wt)., Results: The inducible luciferase expression of HepG(2)-Luc cells was noted in a time-, dose-, and AhR-dependent manner, which peaked at 4 h and then decreased to a stable level at 14 h after TCDD treatment. The responsiveness of HepG(2)-Luc cells to TCDD induction was decreased with culture time and became undetectable at 10th month of HepG(2)-Luc cell formation. The fact that luciferase activity induced by 3, 3', 4, 4'-PCB in HepG(2)-Luc cells was much less than that induced by TCDD suggests a structure-inducibility relationship existing among DLCs. Within the concentrations from 3.5 x 10(-12) to 5 x 10(-9) mol/L, significant correlations between TCDD doses and EROD activities were observed in both HepG(2)-luc and HepG(2)-wt cells. The correlation between TCDD doses from 1.1 x 10(-13) to 1 x 10(-8) mol/L and luciferase activities was also found to be significant in HepG(2)-luc cells (r=0.997, P<0.001), but not in their HepG(2)-wt counterparts. For the comparison of the enzyme responsiveness between cell lines to TCDD, the luciferase sensitivity and reproducibility in HepG(2)-luc cells were both better than that of EROD in HepG(2)-wt cells, the former was at 1.1 x 10(-13) mol/L and 3.5 x 10(-12) mol/L, and the coefficients of variation (CV) of the latter was 15-30 % and 22-38 %, respectively., Conclusion: The luciferase expression of HepG(2)-luc cells established in the present study could sensitively respond to the DLCs stimulation and might be a prospective tool for the determination of DLCs.