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The Jaynes-Cummings-Hubbard (JCH) model is a fundamental many-body model for light-matter interaction. As a leading platform for quantum simulation, the trapped ion system has realized the JCH model for two to three ions. Here, we report the quantum simulation of the JCH model using up to 32 ions. We verify the simulation results even for large ion numbers by engineering low excitations and thus low effective dimensions; then we extend to 32 excitations for an effective dimension of 2^{77}, which is difficult for classical computers. By regarding the phonon modes as baths, we explore Markovian or non-Markovian spin dynamics in different parameter regimes of the JCH model, similar to quantum emitters in a structured photonic environment. We further examine the dependence of the non-Markovian dynamics on the effective Hilbert space dimension. Our Letter demonstrates the trapped ion system as a powerful quantum simulator for many-body physics and open quantum systems.

回顾性分析1例原发于椎管内硬脊膜的黏液型孤立性纤维性肿瘤（SFT）的临床病理学特点、诊断、鉴别诊断及临床预后等。患者女，39岁。右侧背部疼痛、右小腿麻木伴行走不稳3个月；磁共振成像（MRI）提示胸椎椎管内占位，考虑神经鞘瘤可能，手术完整切除病灶。显微镜下于黏液背景中见肿瘤细胞弥漫性生长，瘤细胞体积中等大小，呈短梭形或星芒状，胞质淡染，细胞核轻微不规则；间质内可见薄壁、扩张的血管。免疫组织化学染色肿瘤细胞表达STAT6和CD34，不表达脑膜瘤标志物SSTR2，不表达神经鞘瘤标志物S-100蛋白、SOX10和脊索瘤标志物Brachyury，Ki-67阳性指数约5%。二代测序检测提示其存在NAB2基因的第6号外显子和STAT6基因的第17号外显子融合。术后随访1年无肿瘤复发和转移。中枢神经系统黏液型SFT罕见，预后较好，诊断过程中需注意与黏液样神经鞘瘤、脊索瘤、脊索样脑（脊）膜瘤、原发或者转移性黏液样单相型滑膜肉瘤以及原发或者转移性低度恶性纤维黏液样肉瘤等疾病相鉴别。.

Quantum simulation provides important tools in studying strongly correlated many-body systems with controllable parameters. As a hybrid of two fundamental models in quantum optics and in condensed matter physics, the Rabi-Hubbard model demonstrates rich physics through the competition between local spin-boson interactions and long-range boson hopping. Here we report an experimental realization of the Rabi-Hubbard model using up to $16$ trapped ions and present a controlled study of its equilibrium properties and quantum dynamics. We observe the ground-state quantum phase transition by slowly quenching the coupling strength, and measure the quantum dynamical evolution in various parameter regimes. With the magnetization and the spin-spin correlation as probes, we verify the prediction of the model Hamiltonian by comparing theoretical results in small system sizes with experimental observations. For larger-size systems of $16$ ions and $16$ phonon modes, the effective Hilbert space dimension exceeds $2^{57}$, whose dynamics is intractable for classical supercomputers., 6 pages, 3 figures + 13 pages, 10 figures

The chondroitin sulfate (CS)/sodium alginate (SA)/chitosan nanoparticles were prepared by electrostatic spraying technology. Laser particle size analyzer measurements indicated that the size of the particles is strongly affected by the weight ratio of raw materials, receiver rotation speed, injection rate, and so on. The size increased and size distribution moved towards the direction of large particle size with the decrease of applied voltage and increased with the increase of the flow rate and weight ratio of SA to CS; there is an optimal value for the effect of stirring rate on particle size and particle size distribution. The effect of different weight ratios of raw materials and pH on the sustained release rate of the product was investigated using a UV-visible spectrophotometer. Results showed the cumulative release rate of these particles was weight ratio of SA to CS and pH-dependent. The cumulative release rate of the CS/SA/chitosan composite nanoparticles with a weight ratio of SA to CS of 2 : 1 was higher at pH 6.8 than that at pH 1.2. By optimizing the process parameters, the CS/SA/chitosan composite particles were prepared, in which most of CS could pass through the stomach and release in the intestinal tract.

We present and discuss the role of nanoparticles size and stoichiometry over the local atomic environment of nanostructured VOx films. The samples have been characterized in situ using X-ray absorption near-edge structure (XANES) spectroscopy identifying the stoichiometry-dependent fingerprints of disordered atomic arrangement. In vanadium oxides, the ligand atoms arrange according to a distorted octahedral geometry depending on the oxidation state, e.g. trigonal distortion in V2O3 and tetragonal distortion in bulk VO2. We demonstrate, taking VO2 as a case study, that as a consequence of the nanometric size of the nanoparticles, the original ligands symmetry of the bulk is broken resulting in the coexistence of a continuum of distorted atomic conformations. The resulting modulation of the electronic structure of the nanostructured VOx as a function of the oxygen content reveals a stoichiometry-dependent increase of disorder in the ligands matrix. This work shows the possibility to produce VOx nanostructured films accessing new disordered phases and provides a unique tool to investigate the complex matter.

This paper focuses on removal niobium from Nb-bearing hot metal by bottom blown-CO2 gas at flow rate of 1,0×103 Nm3/h, 1,5×10-3 Nm3/h at 1350 °C and 1 450 °C in a medium induction furnace. The results show that Nb and P are oxidized and the ratio of Nb to P in Nb-bearing slag at blowing termination reaches to 46,66 at 1350 °C and CO2 flow rate of 1,5m3/h, which is more than that in the other condition; it improves to remove more Nb from hot metal with bottom-blown CO2 at 1 350 °C than at 1450 °C; Nb starts to oxidize by CO2 to form slag when Si content in molten iron decreases to low 0,1 wt. %.

VO2 is a strongly correlated material, which undergoes a reversible metal insulator transition (MIT) coupled to a structural phase transition upon heating (T = 67 degrees C). Since its discovery, the nature of the insulating state has long been debated and different solid-state mechanisms have been proposed to explain its nature: Mott-Hubbard correlation, Peierls distortion, or a combination of both. Moreover, still now, there is a lack of consensus on the interplay between the different degrees of freedom: charge, lattice, orbital, and how they contribute to the MIT. In this manuscript, we will investigate across the MIT the orbital evolution induced by a tensile strain applied to thin VO2 films. The strained films allowed to study the interplay between orbital and lattice degrees of freedom and to clarify MIT properties.

OBJECTIVE: To evaluate the barrier effect of an absorbable barrier membrane made by small intestinal submucosa (SIS) compared with Bio-Gide collagen membrane. METHODS: 12 healthy New Zealand male white rabbits were randomly assigned. A or B round bone defects with a depth of 2 mm and a diameter of 5 mm or 8 mm was made in each rabbit’s mandibular. The following treatments were given respectively: covered with SIS membrane (S), covered with Bio-Gide membrane (G) and blank control (O). Then we got six groups: AS, AG, AO, BS, BG, and BO (n=4). After 4 weeks, the rabbits were sacrificed. The specimens were examined by naked-eye observation, new bone percentage (BV/TV) and bone mineralized density (BMD), which were measured and analyzed by Micro-CT. The data were analyzed with one-way ANOVA. RESULTS: After 4 weeks, Bio-Gide membranes were fused with the surrounding tissue while SIS membranes held the form with no significant degradation. In the AS, BS and AG groups, the absorbable membranes smoothly covered on the new bone. While in the BG group, Bio-Gide membranes collapsed to the center of the bone defects. The 3D reconstruction of Micro-CT showed that a large number of newly formed trabeculae were found in the four groups of AS, BS, AG, and BG. In the central subsidence area of the BG group, the newly formed trabeculae were sparse. However only a small amount of new bone trabecula appeared at the bottom of the defects in groups AO and BO. Micro-CT quantitative results showed that BV/TV (39.10%±0.79%) and BMD [(517.73±11.22) mg/cm(3)] of AS group were significantly higher than those of AO group [26.67%±1.12%, (319.81±8.00) mg/cm(3)] (P < 0.05), and there was no significant difference between AS group and AG group [38.15%±0.91%, (518.65±7.48) mg/cm(3)] (P>0.05). BV/TV (34.90%±1.35%) and BMD [(409.09±8.14) mg/cm(3)] of BS group were significantly higher than those of BO group [23.63%±2.07%, (171.00±16.24) mg/cm(3)] (P < 0.05). Meanwhile, there was no significant difference between BS and BG groups [33.40%±1.06%, (412.70±8.6) mg/cm(3)] (P > 0.05). HE staining analysis revealed that significant bone formation was achieved in the AS, AG, BS and BG groups, and trabecular bone of AS and AG groups were thicker and denser. In AO and BO group, there were scattered new bone tissues in edges of host bone, and no coarse trabecular bone formed. CONCLUSION: In the early healing of two sizes bone defects in rabbit mandibular, SIS membrane and Bio-Gide membrane have a similar barrier effect in guided bone regeneration. And SIS membrane's ability to maintain space for bone regeneration seems to be better.

This paper focuses on oxidationS behavior of C, Si, Mn, P, Nb in Nb-bearing hot metal during bottom-blowing oxygen in a vacuum-induction furnace. This blowing process was carried out separately with and without slag at the flow rate of 0,4 m2/min to 0,6 m2/min. The results show that niobium is massively removed from the hot metal while silicon content in hot metal is decreased to lower than 0,01wt. % with adding slag , P content keeps unchanged, and sulfur content is decreased in hot metal at the beginning of blowing stage while it increased in hot metal with the extension of smelting time.

The dynamic compression properties of two aluminum alloys 7A62 and 7085 were tested using Split Hopkinson Pressure Bar (SHPB ) technique. The effects of strain rate on yield stress and dynamic energy absorption characteristics of the two materials were analyzed. The critical strain rate and the maximum energy absorbed before shear failure occurred of the two materials were given. The results showed that both the two materials show a strong strain rate dependence effect, and the yield stress increased with increasing strain rate. The aluminum alloy 7085 has a lower yield stress than 7A62 under the same strain rate level. But it has a better energy absorption characteristic than 7A62 for its good plasticity.

To evaluate the bonding ability of one representative self-etch adhesive system by applying the micro-shear bond strength test method with different concentrations of carbodiimide [1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, EDC] ethanol solution pretreatment.Extracted sound human third molars were collected from patients ranging 18 to 40 years. In the study, 80 molars were first sectioned to prepare a flat middle coronal dentin surface and then were randomly divided into 5 groups (n=16) according to without/with different surface treatments [blank control; 80% (volume fraction) ethanol control; EDC ethanol solution of three concentrations (0.01 mol/L, 0.3 mol/L and 0.5 mol/L)]. Each specimen underwent a micro-shear bond strength test and failure mode observation. The data collected were subjected to statistical analysis using one-way ANOVA and post hoc Tukey's test to analyze the difference of the micro-shear bond strength, and chi-square test/Fisher's exact test for the failure mode frequency of the micro-shear bond strength test specimens at a significance level of P=0.05.The micro-shear bond strength of the three concentration EDC treatments were (35.29±8.97) MPa (0.01 mol/L EDC treatment group), (40.24±9.68) MPa (0.3 mol/L EDC treatment group), (37.38±9.66) MPa (0.5 mol/L EDC treatment group) separately; and that of the 80% ethanol group was (37.49±7.76) MPa. All micro-shear bond strength value of the above four groups was statistically higher than that of the blank control group [(33.81±7.98) MPa]. The immediate micro-shear bond strength and failure mode was of no statistically significant difference among all the groups. It was noticed that the immediate micro-shear bond strength of 0.3 mol/L was higher than that of all the other groups, especially higher than that of the 80% ethanol pretreatment group despite that there was no significant difference among all the groups. And the test of failure mode indicated that the cohesive failure was more common, while the frequency of adhesive failure was rare in each experimental group.EDC pretreatment had no adverse effect on the immediate micro-shear bond strengths of Clearfil SE Bond. Meanwhile, EDC treatment did not cause more adhesive failure in immediate micro-shear test, which had further denoted what was said above. However, it needs more research to illustrate the anti-enzymatic role of EDC in dentin bonding.

The plasma screening effect on electron-impact excitation is studied by using the relativistic distorted-wave description and exemplified by the excitation of Ti21+ ion. The total and differential cross sections for the 1s–2s and 1s–2p excitations are calculated in the energy range from threshold to 5 times threshold energy, and the magnetic sublevel cross sections are also given. Comparison of present calculations with other results, when available, is made.

Men with type 2 diabetes (T2D) and obesity are often characterised by low testosterone (T). We aimed to determine whether exenatide (EXE) combined metformin (MET) treatment has a better effect on serum total testosterone (TT) levels than glimepiride (GLI) combined MET treatment in men with T2D and obesity. In a multicentre, 12-week observational study, 176 obese T2D men with failed glycaemic control were included in the study: ninety men (mean age, 43.00 ± 8.50 years) in EXE + MET group and 86 men (mean age, 44.00 ± 7.00 years) in GLI + MET group. Serum TT levels were more significantly increased in EXE + MET group than GLI + MET group (121.72 ± 56.73 ng/dl versus 34.67 ± 16.30 ng/dl). The increasement of TT levels in those patients who lost body weight ≥5% was significantly greater than those who lost weight

A target composition scheme to optimize the combined proton acceleration regime is presented and verified by two-dimensional particle-in-cell (2D PIC) simulations by using an ultra-intense circularly-polarized (CP) laser pulse irradiating an overdense hydrocarbon (CH) target, instead of a pure hydrogen (H) one. The combined acceleration regime is a two-stage proton acceleration scheme combining the radiation pressure dominated acceleration (RPDA) stage and the laser wakefield acceleration (LWFA) stage sequentially together. With an ultra-intense CP laser pulse irradiating an overdense CH target, followed by an underdense tritium plasma gas, protons with higher energies (from about $20$ GeV up to about $30$ GeV) and lower energy spreads (from about $18\%$ down to about $5\%$ in full-width at half-maximum, or FWHM) are generated, as compared to the use of a pure H target. It is because protons can be more stably pre-accelerated in the first RPDA stage when using CH targets. With the increase of the carbon-to-hydrogen density ratio, the energy spread is lower and the maximum proton energy is higher. It also shows that for the same laser intensity around $10^{22}$ $Wcm^{-2}$, using the CH target will lead to a higher proton energy, as compared to the use of a pure H target. Additionally, proton energy can be further increased by employing a longitudinally negative gradient of a background plasma density., Comment: 16 pages, 8 figures

Nine types of muffins made with three levels of β-glucan and three amylose-amylopectin ratios were prepared at the Beltsville Human Nutrition Research Center, United States Department of Agriculture. They were fed to human subjects to study effects of starch composition and dietary fiber content on the carbohydrate and lipid metabolism in normal and overweight women. The main objective of this study was to determine resistant starch (RS) and total dietary fiber (TDF) content of the muffins 1) using AACC Approved Method 32-07 and AOAC method 991.43, incorporating a pretreatment step with dimethyl sulfoxide (DMSO) before enzyme incubation, 2) with pretreatment at 100 and 121°C before incubation with amyloglucosidase, and 3) using samples chewed by human subjects before incubation with pancreatin and amyloglucosidase. For method 1, on an as-eaten basis, TDF content was 2.81 to 9.64 g/100 g for samples without DMSO pretreatment and 1.66 to 4.06 g/100 g with DMSO pretreatment. RS content was 0.30 to 1...

Fuzzy clustering based on fuzzy relations is improved and the concept of weighted clustering is introduced in this paper. To make the process more efficient, the clustering and grading are fulfilled simultaneously. This model is applied in the overall programming process in some regions of China.

Based upon R.R. Yager's concept of bags [1], a definition of fuzzy bags and corresponding operations such as peak value, grade of concentration as well as the relative cardinality is introduced here. Several examples are also given to show the usefulness of fuzzy bags.

In the reference [E. Zienicke, B.W. Li, A. Thess, A. Kratzschmar, P. Terhoeven, Stability Analysis of the Liquid Metal Pinch Using the Shallow Water Approximation, in Fifth International pamir Conference on Fundamental and Applied MHD, Ramatuelle, France-2002, Vol. 1, p.I-51~I-56], a simple physical model for a cylindrical jet of liquid metal passed through by an axial electrical current is introduced and its corresponding mathematical model based on shallow water approximation is deduced. In this paper, the MHD pinch instability is analyzed and compared with results from reference, and hence to guide the application of MHD pinch in construction of electric current switch. Besides this a pseudo spectral method is used to successfully simulate the time evolution of the pinch process. The numerical calculations showed that the nonlinear phase of the pinch process is very short. It starts approximately with a relative perturbation about 1/10 and needs around 0.2ms for GaInSn with a radius of R0 = 1cm and an overload factor of 10 above the critical current density. The shortness of the nonlinear phase is due to a strong self—acceleration of the pinch. If one wants to use the shortness of the nonlinear pinch phase the geometrical design of the switch has to give an initial narrowing of the current path by at least one tenth of the radius.

To breed new varieties of Biantiao ginseng for high yield and fine quality.Systemic breeding methods were applied. About 3,000 outstanding Biantiao ginseng roots were selected and planted in breeding field, and self-crossed for four generations. During the course, inferior lines or plants were rejected. Then strain comparison, identification of resistance to black-speck disease, and analysis of active compositions were carried out."Biantiao 1" (BT1), the first new variety of Biantiao ginseng, with green stems and thick, long, elegant roots and median resistance to black-speck disease, has been harvested since 20 years. The percentage of Biantiao ginseng roots and yield were 15% and 30% higher than the control's respectively. The content of total ginsenosides and the main monomers was 1.8%-2.5% higher than the control's. The characteristics of overground part and root of BT1 were uniform and stable.BT1, a new excellent ginseng variety, has a good potential value to be generalized in ginseng production.

Visual motion perception is one of the most prominent functions performed by the mammalian cerebral cortex. The moving images are commonly considered to be processed in two stages. The first-stage neurons are sensitive to the motion of one-dimensional orientated components, and their outputs are combined at the second stage to perceive the global motion of the whole pattern. Alternatively, the pattern motion may be signalled by monitoring a distinctive feature of the image, such as a line-end or a corner. In the present study, a series of 'random-line' patterns were used to measure the direction-tuning responses of 138 neurons in the posteromedial lateral suprasylvian area of the cat. The novel stimuli comprised identical thin line segments, with a length : width ratio no less than 10 : 1, which were moved perpendicularly or obliquely to their common orientation during the recordings. When the component lines were much shorter than the size of receptive field, the majority of cells were selective to the direction of pattern motion while only a small subset was sensitive to the direction of component motion. However, the response profiles of most cells became more component-motion selective with the increment of orientation element in stimulus by elongating the component lines in the patterns. These findings imply that the two-stage theory might be incomplete for modelling the visual motion analysis. Even at relatively low levels of the visual system, some kind of nonorientation-based processing may coexist with the orientation-sensitive processing in a dynamic competition, where one rises as the other falls depending upon the strength of the orientation element in the stimulus, so that under some circumstances it becomes possible to signal the veridical direction of pattern motion.

The processing of optic flow information has been extensively investigated in the medial superior temporal area (MST) of the macaque. In the cat, the posteromedial area and the posterolateral area in the lateral suprasylvian cortex (PMLS and PLLS, respectively) have been suggested as likely participants according to their direction preferences to moving objects. In the present study, 203 PMLS and 123 PLLS neurons were tested with simulated optic flow patterns composed of random dots (including expansion and contraction, clockwise and counter-clockwise rotation, and translation) and moving bar stimuli. About 90% of the neurons were found to be excited by the optic flow stimuli and most of them were multiple-responsive to different flow patterns. Only 20-25% of the cells were selective to different optic flow modes, and in general, the direction preference was fairly modest. The selective cells showed stronger directionality to both flow field and moving bar than nonselective cells. However, the optic flow response properties in the PMLS and PLLS were not well correlated with the direction preference to moving bars. In accordance with previous findings, the PMLS was analogous to the middle temporal area of the macaque in many respects. As for the PLLS cells, they were sensitive to fewer types of stimuli, but responded better and more selectively to radial motion. All these results suggest that the two lateral suprasylvian areas are unlikely to be specialized for the analysis or discrimination of different flow patterns, but may play some kind of relay role in optic flow information processing.

Hydrolysis of dietary fiber polysaccharides (DFP) is an integral part of any enzymatic-chemical method for dietary fiber analysis. Residues obtained after enzyme treatments of fiber-containing foods are usually suspended in 12 M sulfuric acid and kept at or slightly above ambient temperature for at least 1 h, and then the mixtures are diluted with deionized water to a final concentration of 1 M or 2 M acid, followed by heating at 100 degrees C in a water bath or convection oven for 1 or 2 h. Under these hydrolytic conditions, some degradation of the released monosaccharides generally takes place over the duration of hydrolysis. We investigated the feasibility of using microwave energy as a heat source to reduce time and minimize degradation. Preliminary tests were done on the well-characterized soy polysaccharide Fibrim. With a microwave digestion system equipped with temperature and pressure monitors and control lines, optimum settings of power (5%, 75%), time (up to 3 min and 30 s), temperature (35 degrees-55 degrees C), and pressure (45-65 psi) were determined for different foods depending on the residue weight and volume of acid. Results were comparable for microwave oven and convection oven hydrolysis of DFP from 5 foods with good correlations for neutral sugar values; r2 = 0.997 for arabinose, 0.925 for galactose, 0.981 for glucose, 0.969 for mannose, and 0.990 for xylose.

To explore therapeutic mechanism of Shengyi Xieli Mixture (SYXLM) on malignant tumor.Chemotherapy, radiotherapy and different doses of SYXLM were used to treat tumor mice [correction of rats].SYXLM could enhance the nature killer (NK) cell activities of the tumor mice [correction of rats], and this effect was dose dependent (control group 52.70 +/- 6.01, SYXLM No. 1 group 59.01 +/- 10.00, SYXLM No. 2 group 78.33 +/- 10.90, P0.01). The NK cell activities of the tumor mice [correction of rats] were inhibited in the chemotherapy group alone, but they were enhanced in the group of chemotherapy combined with SYXLM (P0.05), the results were the same in the radiotherapy group alone and the group of radiotherapy combined with SYXLM (P0.05). The response of lymphocyte of the tumor mice [correction of rats] to IL-2 was enhanced significantly in SYXLM group compared with the control group. This response was enhanced insignificantly in the group in which radiotherapy combined with the SYXLM.The SYXLM could enhance the function of immune system of the tumor mice [correction of rats] and diminish or reduce the side effect of radiotherapy, chemotherapy to the immune system of the tumor mice [correction of rats].

Three extraction methods were used to remove lipid materials from 8 edible nuts and seeds before analysis for their total dietary fiber (TDF) and nonstarch polysaccharide (NSP) contents. Portions of ground materials were extracted by: n-hexane, followed by 80% methanol, n-hexane-acetic acid (95 + 5, v/v), and supercritical carbon dioxide. Defatted samples were gelatinized in water and incubated with amyloglucosidase; 95% ethanol was added to the hydrolyzates, and the residues were collected on tared glass crucibles. TDF was calculated according to a simplified enzymatic-gravimetric method developed in our laboratory, and NSP was determined as described by Englyst and coworkers. Dietary fiber values obtained with any of the extraction methods range from 3.47 g/100 g for cashews to 28.56 g/100 g for sunflower seeds. Nonstarch polysaccharide values range from 2.43 g/100 g for pecans to 5.56 g/100 g for peanuts. With the exception of sunflower seeds, samples extracted with supercritical carbon dioxide had lower TDF contents but similar amounts of NSP compared with samples extracted by the other 2 methods.

In this Letter, we use the nanoindentation technique and vary the testing temperature to above and below critical values to study the nanomechanical features of a strong Pb-free piezoelectric Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-0.5BCT) thin film across its piezoelectric-optimal morphotropic phase boundary. The mechanisms responsible for the Young's modulus and hardness evolution are then discussed. An X-ray diffraction method that can detect the d(110) variation associated with the change in the inclination angle ψ of the (110) plane was developed to quantify the residual stress in the BZT-0.5BCT films.

A general scheme has been developed to determine sugars, starches, and total dietary fiber (TDF) in half-gram freeze-dried subsamples of various foods (or wet samples containing about 0.5 g dry matter). Duplicate subsamples are extracted for free sugars with 80% methanol, dried, derivatized to their trimethylsilylated oximes or ethers, and quantitated by gas-liquid chromatography (GLC). Residues after 80% methanol extraction are incubated with a solution containing amyloglucosidase in acetate buffer. Hydrolyzates are centrifuged, and duplicate aliquots are removed for glucose determination by GLC. Starch content is calculated as glucose (g/100 g) x 0.9. Remaining hydrolyzates are diluted with 4 volumes of 95% ethanol, left at room temperature for 1 h, and then filtered through glass crucibles matted with Celite filter aid. The weight of dry residues are corrected for residual crude protein and ash, and the resulting values are taken to be the TDF content of a sample. A variety of high-consumption foods selected by the Nutrient Data Laboratory of the Agricultural Research Service were analyzed for carbohydrate fractions by this method. Values for total sugar and dietary fiber were compared with those obtained by a commercial laboratory using different methods.

A simplified enzymatic-gravimetric method for total dietary fiber (TDF) determination has been published and used in the Food Composition Laboratory of the U.S. Department of Agriculture since 1988. THis method gives comparable results to AOAC Official Methods 985.29 and 991.43 but the AOAC methods use 100 degrees C (water bath) to gelatinize the sample and a combination of alpha-amylase and an amyloglucosidase to hydrolyze starches, whereas the simplified method incorporates an autoclaving step (121 degrees C) for gelatinization followed by incubation with only amyloglucosidase. The simplified method omits protease hydrolysis and does not require any pH adjustment. Overall, the simplified method cuts cost and is less labor intensive. An interlaboratory study was conducted to validate this method. Blind duplicates of six sample (baked beans, corn bran, roasted peanuts, cooked potatoes, white bread with reduced calories, and cooked white rice) were sent to 11 laboratories. The reproducibility relative standard deviations of the TDF values (without outliers) ranged from 3.46 to 27.6%. The repeatability standard deviations ranged from 0.91 to 14.6%.

Although Lyme disease is commonly seen in the southcentral United States, the epidemiology of the disease is poorly defined there. The purpose of this study was to document the presence of Borrelia burgdorferi in ticks collected in southeastern Missouri and around the city of St. Louis. Spirochetes were detected and identified as B. burgdorferi by immunofluorescent antibody (IFA) tests using the monoclonal antibody H5332 in 1.9% of Amblyomma americanum and 2.0% of Dermacentor variabilis ticks collected. The identity of IFA-positive organisms was verified by polymerase chain reactions (PCRs) with two different sets of B. burgdorferi-specific primers followed by Southern blotting. The DNA sequences of amplified 371-basepair PCR products from two positive Missouri ticks showed 97-98% identity with that obtained by the same method for the B31 strain of B. burgdorferi. These results confirm that B. burgdorferi is present in questing D. variabilis and A. americanum ticks in areas of Missouri where Lyme disease occurs. Additional studies are needed to determine the role of these ticks in the epidemiology of Lyme disease in Missouri and neighboring states.

A collaborative study was conducted to validate a nonenzymatic-gravimetric method for the determination of total dietary fiber (TDF) of samples containing little or no starch such as most fruits, and vegetables and many purified polysaccharides. This simple procedure involves suspension of freeze-dried, ground samples in deionized water and incubation at 37 degrees C for 90 min, followed by precipitation with 4 volumes of 95% ethanol. The weight of the dilute alcohol-insoluble residues after correcting for crude protein and ash corresponds to the TDF content of the sample. Six samples in blind duplicate (apples, apricots, cabbage, carrots, onions, and soy fiber) were sent with Celite to 10 laboratories. The reproducibility relative standard deviation (RSDR) of the TDF values for 9 laboratories ranged from 2.92 to 6.25%. The repeatability standard deviation (RSDr) for the 9 laboratories ranged from 1.50 to 2.70%. The method has been adopted first action by AOAC INTERNATIONAL.

Vaccination with irradiated infective larvae induces partial protective immunity to infection with the filarial nematode Brugia malayi in jirds. Prior studies have shown that such immunization stimulates a much stronger antibody response to recombinant and native filarial paramyosin than that seen after normal infection. To determine whether vaccination with recombinant paramyosin could induce protective immunity to larval challenge, jirds were immunized with either B. malayi paramyosin and maltose binding protein (BM5-MBP) (fusion protein of B. malayi paramyosin and maltose-binding protein), MBP alone, or recombinant Dirofilaria immitis paramyosin. Animals were challenged with 100 infective larvae s.c. 8 wk after the second immunization. Necropsies were performed 16 wk after challenge. Vaccination with BM5-MBP induced significant protective immunity; adult worm recoveries, worm lengths, and blood microfilaria counts were reduced in the BM5-MBP group relative to the MBP control group. The reductions in adult worm recoveries (43%) and female worm lengths (10%) were statistically significant (p0.05). Interestingly, protective immunity was not induced by immunization with D. immitis paramyosin. Additional studies are needed to identify mechanisms involved in protective immunity induced by BM5-MBP and to understand the differential activity of the two closely related recombinant paramyosin proteins in this model.

The genomic DNA of the two lung flukes (P. westermani and P. skrjabini) from six areas was digested separately by three restriction endonucleases BamHI, Hae III and Hind III, followed by agarose gel electrophoresis. Repetitive DNA were visualized as distinct bands in stained gels. Restriction fragment length differences were detected between the two species. The majority of bands of repetitive DNA were similar with minor differences within the same species collected from different areas, upon digestion with certain restriction endonucleases. The results demonstrated that the technique for demonstrating the band pattern of repetitive DNA with three restriction endonucleases can be used for the identification of P. westermani and P. skrjabini and the geographic relationship of the same species from different areas (Figs. 1-3).

Genomic DNA were prepared from 5 sibling species of Anopheles hyrcanus group including An. sinensis (ASS), An. anthropophagus (ALA), An. liangshanensis (ALS), An. crawfordi (ACW) and An. xiaokuanus (AXK). High molecular weight DNA from each species were cut with three restriction endonucleases (Bgl II, Hae III and Pst I) and the DNA fragments analysed by agarose gel electrophoresis and ethidium bromide staining. Three enzymes (Bgl II, Hae III and Pst I) produced unique fragments in all sibling species tested. A diagnostic restriction fragment length of DNA from 5 sibling species of An. hyrcanus group may be derived from a single restriction enzyme pattern (i.e. Bgl II). The results demonstrated that the restriction fragment length differences of repetitive DNA could used as a tool to distinguish sibling species of An. hyrcanus group.

Total DNA was extracted from three geographical strains of Anopheles sinensis and two geographical strains of Anopheles anthropophagus and digested respectively with three restriction endonucleases (Bgl II, Hae III and Pst I). The restriction fragment length differences (RFLDs) of repetitive DNA detected after agarose gel electrophoretic separation and ethidium bromide staining were compared among the above-mentioned geographical strains of both An. sinensis and An. anthropohagus. The results indicated that the band patterns are species- specific and strain-specific, their main bands being similar while their minor bands being distinctly different. Pst I digestion produced unique fragments for three geographical strains of An. sinensis while Bgl II digestion produced unique fragments for two geographical strains of An. anthropophagus. In view of the variation in repetitive DNA of different geographical strains of both An. sinensis and An. anthropophagus presented, the RFLDs could be used as a means to distinguish various closely related geographical strains of anopheline mosquitoes.

An electron with an appropriate initial velocity injected into an oncoming, ultraintense circularly polarized laser pulse can execute a circular relativistic motion at the peak of the laser pulse. The circulating electron then radiates in the same manner as that in the storage ring of a conventional synchrotron source. Owing to the extremely small orbit radius, the laser-field synchrotron radiation thus generated can be a compact source of radiation pulses at short wavelength and short duration.

The sugar contents of 186 samples of 11 different juices from a nation-wide sampling were determined by the use of a total sugar analyzer (TSA), a gas-liquid chromatograph (GLC) or both. Values for total sugar ranged from 15% in some lemonades on a ready-to-serve basis. Agreement between the two methods was satisfactory.

Trimethylsilylated oximes (TMS-oximes) of arabinose, fucose, galactose, glucose, mannose, rhamnose, xylose, glucuronic acid, and galacturonic acid were prepared using a two-step derivatization procedure. The TMS-oximes were separated and quantitated by gas-liquid chromatography using a 25-m fused-silica capillary column coated with crosslinked methylsilicone stationary phase. Starting with dried sugar extract, the entire procedure can be accomplished within 2 hours.