半透射高光谱多指标同时检测马铃薯内外部缺陷

目的应用半透射高光谱成像技术结合支持向量机(support vector machine,SVM)模型实现马铃薯内外部缺陷多指标同时检测。方法采集310个马铃薯样本半透射高光谱图像,并分别采用标准正态变量变换(standard normalized variate,SNV)、归一化(normalize)和平滑处理(smoothing)对光谱信息进行预处理。进一步采用竞争性自适应重加权算法结合无信息变量消除法(competitive adaptive reweighed sampling algorithm,uninformative variable elimination,CARS-UVE)进行特征波长选择,提高模型识别率。结果原始光谱信息经归一化预处理和竞争性自适应重加权算法结合无信息变量消除法(CARS-UVE)降维后所建的支持向量机(SVM)模型识别结果最优,该方法对合格、绿皮和黑心马铃薯样本预测结果分别为90.7%、88.9%、95.7%,混合识别率为91.3%。结论采用半透射高光谱成像技术结合CARS-UVE方法所建SVM模型能够实现马铃薯内外部缺陷多指标同时检测。     

Very fast ultracentrifugation of serum lipoproteins: influence on lipoprotein separation and composition

A very short run time and small sample volumes in the separation of lipoproteins by preparative ultracentrifugation are needed for several investigations. Recently, a very fast sequential separation method was described that needs only 100 min for one run in a centrifugal field of 625,000 x g. We studied the influence of centrifugal fields of this dimension on lipoprotein separation and lipoprotein particle integrity using a Beckman Optima TLX ultracentrifuge with a TLA-120.2 rotor. Rotor speed (120/90/60/30.10(3) rev./min) and run time (100 min/3 h/6.7 h/27 h) were selected in such a way that the product of centrifugal field and run time remained constant. The first conditions correspond to the very fast ultracentrifugation (VFU) procedure with a centrifugal field of 625,000 x g. Thirty different plasma samples covering a wide range of lipid and protein concentrations were separated in the course of two centrifugal runs at densities of 1.006 and 1.063 kg/l which yielded very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL), and the subnatant of low-density lipoproteins, including high-density lipoproteins (HDL) and concomitant sedimented plasma proteins. The major lipid components of the lipoproteins, triacylglycerols, free and esterified cholesterol, phospholipids and the apolipoproteins B and A-I, were estimated considering the masses of the tube contents after a slicing procedure. Measurements of lipids and proteins showed a very good recovery of better than 94% and 91%, respectively, and precision-within-series (coefficient of variation) of better than 4.2% and 6.5%, respectively. The effects of the rotor speed on the lipoprotein structure appeared to be weak. With increasing rotor speed, VLDL and LDL lipid constituents principally tended to decrease, whereas they increased in the subnatant of the LDL-run. The mean lipoprotein mass composition, considering the mass percentage of each measured particle constituent, did not show significant alterations. Total protein decreased in VLDL and in LDL and increased in the subnatant of the LDL-run. As checked by an enzyme-linked immunosorbent assay (ELISA) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), the protein effects were due to nearly complete disappearance of contaminating plasma proteins, especially albumin as the major contamination of VLDL and LDL. The apolipoproteins (apo) B-100, A-I, E and C-I to C-III remained nearly unaffected. The main advantages of VFU were the very short run time (cumulative flotation time is 3.4 h) and the elemination of albumin without repeated runs. The procedure was suitable for the assessment of lipid and protein constituents in lipoproteins from very small plasma samples (500 microliters).     

Highly efficient Er3+: Pr3+-codoped CW fluorozirconate fiber laser operating at 2.7 µm

We report highly efficient CW fiber lasers at 2.7µm in an Er³⁺-doped and weakly Pr³⁺-codoped fluorozirconate fiber. The fiber lasers were pumped in three pump wavelength ranges around 650, 795 and 980 nm. Higher output powers of nearly 30 mW and a broader potential tuning range of 180 nm compared to Er³⁺ singly doped fiber lasers are demonstrated. Laser efficiencies of more than 13% were achieved. It is shown that the fiber laser can be tuned to longer wavelengths by increasing the pump power or, in certain cases, by increasing the pump wavelength. Furthermore, we present the wavelength tuning of the Er³⁺:Pr³⁺-codoped system by an external grating. The relationships between laser wavelength and pump rates are described, and the reasons for the improvements with Pr³⁺-codoping are given.     

A single and multiple dose bioavailability study with carbamazepine 400 mg retard tablets with reference to enzyme autoinduction and circadian time differences

Both single and multiple dose bioequivalence studies are required to assess the quality of modified release formulations of drugs. In bioequivalence studies of drugs with enzyme autoinducing properties such as carbamazepine (CBZ), the standard multiple dose study design must be modified to guarantee equivalence of drug elimination. This problem was considered with regard to carbamazepine 400 retard AWD (test) whose bioavailability relative to a listed reference (Tegretal 400 retard) was studied in 2 randomized, open, crossover studies both with 18 healthy volunteers of Caucasian origin (20-36 years, 61.5-92 kg, 172-195 cm). The single dose study was done with 400 mg CBZ. Serum concentration time profiles of CBZ and its active metabolite CBZ-10,11-epoxide were determined until 144 h after administration. The multiple dose study was performed with 400 mg CBZ b.i.d. for 15 days (first 2 days: 200 mg b.i.d.) followed by a 7-day study with the alternative investigational product. 24-hour serum concentration time profiles of CBZ and its metabolite were measured on days 15 and 22 of the study. The quantitative drug analysis was done with an HPLC method the quality of which fulfilled the requirements of bioequivalence studies. Test was considered bioequivalent to reference with regard to the extent of absorption, if the 90% confidence intervals of the AUC0-infinity ratio (single dose) and AUC0-24h ratio (multiple dose) were within the range of 0.80-1.25, and with regard to rate of absorption if the 90% confidence intervals of the Cmax/AUC ratio (single dose) or AUCF0-24h ratio were within 0.70-1.43. The point estimators (90% confidence limits) of the AUC ratio (test/reference) of CBZ were 0.979 (0.94, 1.02) for the single and 1.01 (0.947, 1.076) for the multiple dose comparison. The point estimator (90% confidence limits) of the Cmax/AUC ratio was 0.989 (0.959, 1.020) and of the AUCF0-24h ratio 1.066 (0.937, 1.212). There were no circadian time differences in any pharmacokinetic parameter. In conclusion: Carbamazepine 400 retard AWD tablets were bioequivalent to reference with regard to extent and rate of absorption after both single and multiple dose administration.     

Binding of Zinc to Apple Fiber, Wheat Bran, and Fiber Components

Zinc ion binding to commercial brans, fiber, and fiber components was studied by equilibrium dialysis. Maximum initial concentration of zinc bound by 50 ma of apple fiber (AF) and wheat bran (WB) at pH 7.2 was 220 μg. AF and WB binding capacities were significantly lower for soluble fractions than for unfractionated materials. The water-soluble fraction's binding capacity was 90% lower for AF than for WB. Hemicellulase and phytase slightly increased AF binding capacity but reduced WB capacity. Pectinase increased both AF and WB capacity slightly. Binding capacities of commercially available individual fiber components decreased in the order: lignin > polypectin > pectin > gum > cellulose. Zinc-binding capacities of various dietary fiber types differ, accounting for different zinc bioavailabilties of some foods.     

Signal transduction mechanisms involved in angiotensin-(1-7)-stimulated arachidonic acid release and prostanoid synthesis in rabbit aortic smooth muscle cells

This study investigated the signal transduction mechanisms of angiotensin-(1-7) [Ang-(1-7)]- and Ang II-stimulated arachidonic acid (AA) release for prostaglandin (PG) production in rabbit aortic vascular smooth muscle cells. Ang II and Ang-(1-7) enhanced AA release in cells prelabeled with [3H]AA. However, 6-keto-PGF1 alpha synthesis produced by Ang II was much less than that caused by Ang-(1-7). In the presence of the lipoxygenase inhibitor baicalein, Ang II enhanced production of 6-keto-PGF1 alpha to a greater degree than Ang-(1-7). Angiotensin type (AT)1 receptor antagonist DUP-753 inhibited only Ang II-induced [3H]AA release, whereas the AT2 receptor antagonist PD-123319 inhibited both Ang II- and Ang-(1-7)-induced [3H]AA release. Ang-(1-7), receptor antagonist D-Ala7-Ang-(1-7) inhibited the effect of Ang-(1-7), but not of Ang II. In cells transiently transfected with cytosolic phospholipase A2 (cPLA2), mitogen-activated protein (MAP) kinase or Ca(++)-/cal-modulin-dependent protein (CAM) kinase II antisense oligonucleotides, Ang-(1-7)- and Ang II-induced [3H]AA release was attenuated. The CaM kinase II inhibitor KN-93 and the MAP kinase kinase inhibitor PD-98059 attenuated both Ang-(1-7)- and Ang II-induced cPLA2 activity and [3H]AA release. Ang-(1-7) and Ang II also increased CaM kinase II and MAP kinase activities. Although KN-93 attenuated MAP kinase activity, PD-98059 did not affect CaM kinase II activity. Both Ang II and Ang-(1-7) caused translocation of cytosolic PLA2 to the nuclear envelope. These data show that Ang-(1-7) and Ang II stimulate AA release and prostacyclin synthesis via activation of distinct types of AT receptors. Both peptides appear to stimulate CaM kinase II, which in turn, via MAP kinase activation, enhances cPLA2 activity and release of AA for PG synthesis.     

Numerical Analysis of Distortion due to Inhomogeneous Distribution of Martensite Start Temperature within SAE 52100 Bearing Rings

This paper reports about numerical investigations regarding the spatial distribution of martensite start temperature (M_s) within bearing rings made out of SAE 52100 (100Cr6). Out‐of‐roundness values due to inhomogeneous M_s distribution are calculated by means of FE simulations. In a first step the distribution of M_s is modelled with simple trigonometric functions with different wavelengths and amplitudes of M_s. In addition, more complex distributions of M_s are investigated by means of superposition of different trigonometric functions. Simulations with the commercial FE simulation program SYSWELD^® yield dependencies of out‐of‐roundness values of bearing rings on wavelength and amplitude of M_s. The numerical study is supplemented by experimental investigations concerning the distribution of M_s. Typical scatter‐bands of M_s within a work piece were found to be ± 10 K. Concerning this scatter‐band, different possible distributions of M_s are analysed by Fourier transformation. With the resulting trigonometric functions the out‐of‐roundness values are calculated and compared with experimental data.     

An immunohistochemical assessment of cathepsin D in gastric carcinoma: its impact on clinical prognosis

Immunohistochemical staining of normal and cancerous ovarian tissues has demonstrated that both IL-1 alpha and IL-1 beta are more strongly expressed in cancerous than in normal tissues and are secreted mainly by epithelial cells. We have shown by bioassay and immunoassay that cancerous, but not normal ovarian tissues constitutively secrete IL-1 in vitro. Activation of cancerous ovarian tissues by lipopolysaccharide (LPS) increased its capacity to secrete IL-1. Normal ovarian tissues secreted low amounts of IL-1 only after prolonged stimulation (72-96 h) by high doses of LPS (10-100 micrograms/ml). On the other hand, constitutive IL-1 was detected in homogenates of normal ovarian tissues and stimulation by LPS increased its capacity to produce IL-1. IL-1 beta was the main type of IL-1 secreted by cancerous ovarian tissues. IL-1 alpha was detected at lower levels. In contrast, in normal tissues similar amounts of both IL-1 alpha and IL-1 beta were detected in the supernatants. The levels of both types of IL-1, and also the bioactivity of IL-1 were significantly higher in cancerous than in normal ovarian tissues. Established primary cell lines from normal ovarian tissues did not secrete IL-1 into supernatants but did express it at very low levels. Stimulation with LPS did not affect the capacity of these cell lines to secrete IL-1 but it increased their capacity to express it. In contrast, primary established epithelial cell lines from cancerous ovarian tissues did secrete and express high levels of IL-1 and these levels were increased under stimulation with LPS. Cancerous ovarian tissues did not only secrete higher levels of both IL-1 alpha and beta than normal ovarian tissues, but also the mechanism controlling the secretion of these factors in cancerous ovarian tissues seemed to be different from that found in normal ovarian tissues. Our results suggest that paracrine/autocrine factors may be involved in the regulation of both types of IL-1 secreted by ovarian tissues. These cytokines may play a role in regulating the physiological, pathophysiological and oncogenic processes of the ovary.     

Phagocytosis of rod outer segments by human iris pigment epithelial cells in vitro

BACKGROUND: We set out to evaluate the growth potential of human iris pigment epithelial (hIPE) cells in vitro, to establish whether these cells acquire the ability to phagocytose rod outer segments (ROS) and to compare the phagocytic activity of hIPE to that of human retinal pigment epithelial (hRPE) cells. METHODS: hIPE and hRPE cells were isolated and cultured from human donor eyes and surgical specimens and growth characteristics were analyzed. HIPE and hRPE of an eye of a 46-year-old donor were used for the phagocytosis assay. Phagocytosis was evaluated by adding ROS isolated from porcine retina to cultures of hIPE and hRPE, which had been labeled with the pH-sensitive fluorescent dye, carboxy-SNAFL. After 4 h the number of ingested ROS was counted with a light microscope. For each cell type phagosomes in 500 cells were counted. The epithelial characteristics of the cells used in this study were evidenced by their morphology. RESULTS: Morphologically cultured hIPE are indistinguishable from the hRPE cultured from the same donor eye and show a similar pattern of cytokeratin distribution. Cultured hIPE acquire the ability to phagocytose ROS at a level slightly lower than hRPE; hIPE contained 0.76 phagosomes per cell, hRPE 0.99 phagosomes per cell. CONCLUSION: The morphology of hIPE in culture and the acquisition of the phagocytic phenotype indicate that these cells have the ability to differentiate into cells that have characteristics in common with hRPE. The acquisition of phagocytic activity suggests that it is feasible to culture hIPE from surgical iridectomies and that these cultured cells can be transplanted into the subretinal space in individuals with retinal degenerations.     

Value of B-image ultrasound in diagnosis of paranasal sinus diseases in comparison with computerized tomography

BACKGROUND: In diagnostic imaging of the paranasal sinuses, the A-mode technique is increasingly being substituted by B-mode ultrasonography. To assess the value of B-mode sonography we compared in a double-blind study computed tomography with our ultrasound findings. PATIENTS AND METHODS: Seventy-eight patients were examined by CT and subsequently by ultrasound, two-thirds before endonasal surgery and one-third for diagnosis of serious facial pain and swelling. RESULTS: Among 114 pathological maxillary sinus tomograms, 83 findings could also be diagnosed by ultrasound (sensitivity 72.8%). In the frontal sinuses only 12 of 52 of pathological findings could be detected (23.1%) and only 9 of 80 in the frontal ethmoid (11.3%). Except for circumscribed polyps and moderate general swelling of the mucosa, the detection rate by sonography was 97.4% for the maxillary sinuses, 31.5% for the frontal and 18% for the ethmoid sinuses. CONCLUSIONS: Ultrasound usually only demonstrates the presence of absence or unspecific findings. Differential diagnosis between tumors and sinusitis is generally difficult. The healthy individual is correctly assessed as healthy due to the total reflection of the air-filled healthy sinus. According to our findings ultrasound has a certain value in the diagnosis of maxillary sinuses. It can be used to obtain a preliminary diagnosis and as a screening method although a negative result never excludes a disease of the sinuses. As it does not involve radiation exposure, ultrasonography can be recommended as first step in diagnosis for children, pregnant women, and young women especially in acute sinusitis, because in acute sinusitis the maxillary sinuses are generally affected.