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BACKGROUND: Octreotide (SMS) is a somatostatin analogue utilized in patients with short bowel syndrome (SBS) to decrease output. It may inhibit small bowel adaptation by blocking the secretion of trophic hormones such as epidermal growth factor (EGF). This study delineates the effects of SMS and EGF on nutrient transport in SBS. METHODS: One week after 70% jejunoileal resection, 20 New Zealand White rabbits (2 kg) received subcutaneous infusions of saline or EGF (1.5 [mu]g/kg/hr) and injections of saline or SMS s.q. b.i.d. The study groups were EGF/saline, saline/saline, saline/SMS, and EGF/SMS. After 7 days of infusion, intestinal brush border membrane vesicles were prepared and nutrient transport measured. RESULTS: SMS reduced active nutrient transport. Kinetics confirmed this was secondary to a reduction in functional carriers in the brush border membrane, without a change in carrier affinity. The coinfusion of EGF ameliorated this effect. On an individual basis, EGF alone did not significantly increase nutrient transport, but when taken as a group, nutrients transport was upregulated 26%. CONCLUSIONS: SMS is detrimental to small bowel adaptation. EGF reverses this effect and may benefit patients with SBS who require SMS to control high intestinal output. Am J Surg. 1996; 171:267-271.

Systolic blood pressure of more than 185 mm Hg is a contraindication to thrombolytic treatment with intravenous alteplase in patients with acute ischaemic stroke, but the target systolic blood pressure for optimal outcome is uncertain. We assessed intensive blood pressure lowering compared with guideline-recommended blood pressure lowering in patients treated with alteplase for acute ischaemic stroke.

Ammonium perchlorate (AP) is commonly used as an oxidant in composite solid propellants (CSPs). The thermal behavior of AP has a significant impact on CSP combustion. This study investigates the thermal behavior of Al-AP-Fe2O3and Al@AP-Fe2O3particles, which were produced using a recrystallization method, under various pressures. The ability of Fe2O3to regulate the decomposition rate of AP and the reasons for the reduced ignition delay under enhanced Fe2O3catalysis are also explored by using density functional theory (DFT) calculations. The results indicate that Fe2O3with a large catalytic contact area has a strong ability to regulate the decomposition rate of AP. The decreasing trend of the temperature difference between low- and high-temperature decomposition peaks belonging to the Al@AP-Fe2O3(32 °C (0.1 MPa) → 19 °C (1.0 MPa) → 14 °C (4.0 MPa)) is weaker than that of the Al-AP-Fe2O3(60 °C (0.1 MPa) → 25 °C (1.0 MPa) → 0 °C (4.0 MPa)) under various pressures. Additionally, the low activation energy of ∗NH4ClO4→ ∗NH3 + ∗H (∗O3b) + ∗ClO4(300 °C: 0.207 eV) is the main reason for the initial decomposition of AP to accelerate and the ignition delay to be reduced under the more adequate α-Fe2O3catalysis. Furthermore, the catalysis of α-Fe2O3with a large contact area can further facilitate or control the oxidation of NH3under various pressures or temperatures, influencing the decomposition of AP and enabling its regulation. This study therefore highlights the importance of understanding the catalytic properties of Fe2O3for improving the performance of CSPs and optimizing their combustion behavior.

Aluminum (Al) surfaces with ultra-repellency as well as desirable robustness were designed and fabricated. With photolithographic patterning of a thick SU-8 layer and sputtering of a thin Al film, re-entrant micro-pillar textured Al surfaces were prepared. After derivatization with perfluoroalkyl phosphoric acid (FPA), the textured Al surfaces showed ultra-repellency for a wide variety of liquids. The contact angles (CAs) of deionized (DI) water, hexadecane and dodecane were larger than 150°, and those of methanol and ethanol were larger than 100°. The sliding angles (SAs) of DI water, hexadecane and dodecane were 5°, 10°, and 10°, respectively, showing excellent superamphiphobicity. The SAs of methanol and ethanol were in the range of 20°–30°. The robustness of the ultra-repellent Al surface was evaluated by three parameters: robust height (H*), robust angle (T*) and robust factor (A*). For the DI water probing, the values of the parameters are H*≈ 403, T*≈ 119 and A*≈ 92, respectively, indicative of a desirable robustness. We clarified that only re-entrant structures can support composite liquid–solid–vapor interfaces when the corresponding Young’s CAs are smaller than 90°, and the function of the nanometer structures of the hierarchical textures which were widely adopted to fabricate superamphiphobic surfaces is to help construct re-entrant structures. FPA derivatization is effective in lowering the surface energy of Al surfaces, combining with re-entrant textures to provide a simple and high throughput approach to ultra-repellency for a wide variety of liquids.

A completely randomized 3 × 3 + 1 factorial experiment was conducted to evaluate the effects of sources and concentrations of Zn on growth performance, nutrient digestibility, serum biochemical endpoints, and fur quality in growing–furring female black mink. One hundred fifty healthy 15-wk-old female mink were randomly allocated to 10 dietary treatments (n= 15/group) for a 60-d trial. Animals in the control group were fed a basal diet, which consisted of mainly corn, soybean oil, meat and bone meal, and fish meal, with no Zn supplementation. Mink in the other 9 treatments were fed the basal diet supplemented with Zn from either zinc sulfate (ZnSO4), zinc glycinate (ZnGly), or Zn pectin oligosaccharides (ZnPOS) at concentrations of either 100, 300, or 900 mg Zn/kg DM. The results showed that mink in the ZnPOS groups had higher ADG than those in the ZnSO4groups (main effect, P< 0.05). The addition of Zn reduced the G:F (P< 0.05). In addition, CP and crude fat digestibility were linearly increased with Zn supplementation (P< 0.05) and N retention tended to increase with Zn addition (P= 0.08). Dietary Zn supplementation increased the concentration of serum albumin and activity of alkaline phosphatase (P< 0.05). There was a linear effect of dietary Zn on the concentration of tibia Zn and pancreatic Zn (P< 0.05). For fur quality characteristics, the fur density and hair color of mink were improved by dietary Zn concentration (P< 0.05). Compared with ZnSO4(100%), relative bioavailability values of ZnGly were 115 and 118%, based on tibia and pancreatic Zn, respectively, and relative bioavailability values of ZnPOS were 152 and 142%, respectively. In conclusion, this study demonstrates that Zn supplementation can promote growth and increase nutrient digestibility and fur quality and that ZnPOS is more bioavailable than ZnSO4and ZnGly in growing–furring female mink.

Organophosphonic acid derivatisation on aluminium surfaces had been demonstrated to be effective for surface energy control. By following the surface energy control strategy, surperhydrophobic Al surfaces had been achieved via microcolumn pattern and dodecylphosphonic acid (DDPA) derivatisation. The water contact and sliding angles of the superhydrophobic Al surfaces were respectively 156 and 5°. Measurements confirmed that the linkage between DDPA and Al are mainly bidentate P–O–Al. The wetting properties as well as the mechanical durability of the superhydrophobic Al surfaces were tested and discussed.

A comparative slaughter trial was conducted to estimate the trace element concentrations and distributions in the main body tissues and the net requirements for maintenance and growth of Dorper × Hu crossbred lambs. Thirty-five lambs of each gender (19.2 ± 0.36 kg initial BW) were used. Seven lambs of each gender were randomly chosen and slaughtered at approximately 20 kg BW as the baseline group for measuring initial body composition. Another 7 lambs of each gender were also randomly chosen and offered a pelleted mixed diet for ad libitum intake and slaughtered at approximately 28 kg BW. The remaining 21 sheep of each gender were randomly divided into 3 groups with 7 sheep each and assigned to ad libitum or 40 or 70% of ad libitum intake of a pelleted mixed diet (42:58 concentrate:roughage, DM basis). The 3 groups of each gender were slaughtered when the sheep fed ad libitum reached approximately 35 kg BW. Empty body (head + feet, hide, viscera + blood, and carcass) trace element contents were determined after slaughter. The results showed that the trace elements were mainly distributed in viscera (blood included), except for Zn, which was mainly distributed in the muscle and bone tissues. The net requirements were calculated using the comparative slaughter technique. For males and females, the daily net trace element requirements for maintenance were 356.1 and 164.1 μg Fe, 4.3 and 3.4 μg Mn, 42.0 and 29.8 μg Cu, and 83.5 and 102.0 μg Zn per kilogram empty body weight (EBW), respectively. Net requirements for growth decreased from 65.67 to 57.27 mg Fe, 0.35 to 0.25 mg Mn, and 3.45 to 2.82 mg Cu and increased from 26.36 to 26.65 mg Zn per kilogram EBW gain (EBWG) for males. Net requirements for growth decreased from 30.66 to 22.14 mg Fe, 0.43 to 0.32 mg Mn, 2.86 to 2.18 mg Cu, and 27.71 to 25.83 mg Zn per kilogram EBWG for females from 20 to 35 kg BW. This study indicated that the net trace element requirements for Dorper × Hu crossbred lambs may be different from those of purebred or other genotypes, and more data are needed for sheep in general.

The effects of poling state and pores on the fracture toughness of Pb(Zr0·95Ti0·05)O3(PZT 95/5) ferroelectric ceramics were investigated. X-ray diffraction analysis and piezoelectric constant measurements reveal that the phase structures of PZT 95/5 ceramics change with the poling state, which significantly affects the fracture toughness. The poled PZT 95/5 ceramics demonstrate higher fracture toughness than the unpoled ceramics, and their fracture toughness significantly increases after the pressure depoling. As the porosity of ceramics increases with addition of poreformer during preparation, their fracture toughnesses all decrease accordingly either in poled state or unpoled state. The effect of pore size on the fracture toughness is subtle for the poled ceramics, but for the hydrostatic pressure depoled porous PZT 95/5 ceramics, their fracture toughness increases with the increase in pore size. A new stress model is proposed to explain the pore size effect on the fracture toughness of hydrostatic pressure depoled PZT 95/5 ceramics.

In livestock, the ovarian reserve of follicles is established during the fetal stage. However, at least two-thirds of the oocytes present in the reserve die because of apoptosis before birth. Notably, mitochondria have been reported to play a crucial role in the fate (life/death) of oocytes. In this study, mitochondrial regulators nuclear respiratory factor-1 (NRF-1) and PPAR γ coactivator-1 alpha (PGC-1α) were examined during this period of follicle development to investigate their effects on follicular development and apoptosis. Fetal and neonatal Capra haimenwere used, ranging in age from 60 d postcoitum (dpc) to 30 d postpartum (dpp). Our data demonstrated that egg nests were the earliest recognizable gamete cells in ovaries of fetal and neonatal doelings. Proportions of egg nests decreased from 92.68 to 25.08% whereas single follicles increased from 7.32 to 74.92% between 60 and 120 dpc. Subsequently, between 90 and 120 dpc, the proportion of primordial follicles increased from 9.98 to 61.56% (P< 0.01). However, it did not change between 1 and 30 dpp (P= 0.12). The proportion of primary follicles increased from 1.23 to 37.93% between 90 dpc to 1 dpp (P= 0.01) but did not change between 1 and 30 dpp (P= 0.11). Meanwhile, proportions of secondary and tertiary follicles increased in an age-dependent manner. In addition, results of this study suggested that NRF-1 and PGC-1α proteins are mainly localized in germ cells of egg nests, cytoplasm of oocytes, and granulosa cells of follicles ranging from primordial to tertiary follicles. The transcript abundance of NRF-1mRNA was up-regulated in 60-dpc-old ovaries compared with 1-dpp-old ovaries (P< 0.05), but the PGC-1α mRNA expression pattern did not change (P= 0.05). Nevertheless, the number of terminal deoxynucleotidyltransferase UTP nick-end labeling (TUNEL) positive cells and caspase-3 activity in 60-dpc-old ovaries was less than those in 1-dpp-old ovaries (P< 0.01, P= 0.01). In conclusion, our results demonstrate that the key stage of primordial follicle formation is between 90 and 120 dpc in Capra haimen. Also, this study suggests that NRF-1 and PGC-1α might have roles in cell apoptosis during ovarian development of fetal and neonatal Capra haimen. These results improve our understanding of apoptotic mechanisms in oogenesis and folliculogenesis.

50 wt.‐% of Ce0.8Sm0.2O2(SDC) is added to La0.85Sr0.15Cr0.9Ni0.1O3(LSCN) to investigate its use as an alternative anode for solid oxide fuel cells, especially for hydrocarbon fuels. When LSCN is mixed and sintered together with SDC or YSZ at 1,500 °C for 12 h, no obvious second phase is observed from the XRD patterns. Although the conductivity of LSCN‐SDC is lower than LSCN, the polarization overpotential is reduced by a factor of 10. The mixed electronic‐ionic conductivity of SDC enlarges the reaction zone and improves the catalytic activity of the anode. The interface bonding between LSCN and the YSZ electrolyte is also modified by the nanometer SDC. An improved output performance on a self supported SOFC (LSCN‐SDC/YSZ/PSM‐YSZ) is obtained with H2fuel compared with CH4fuel.

In this paper, time-of-flight secondary ion mass spectrometry (ToF−SIMS) under static conditions was used to investigate self-assembled monolayers (SAMs) of octadecylphosphonic acid (OPA) formed on freshly cleaved muscovite mica substrates. The coverage of OPA on mica ranged from 20 to 100%, with a film thickness of 1.7 ± 0.2 nm, which was determined by atomic force microscopy (AFM) imaging. The relative intensity of the specific secondary ion species associated with the OPA and with the exposed mica substrate exhibited good correlation with surface coverage. An excellent correlation was also observed (R2 0.98) between the relative SIMS OPA-H-intensity and the surface carbon concentration (OPA C 1s, in atomic %) from XPS at the prescribed surface coverage. The observation of positive and negative OPA molecular attachment of secondary ions involving the substrate species is discussed in terms of the chemical affinity of the OPA phosphonate headgroup for the cleaved mica surface as well as the sampling depth. In addition, the OPA molecular attachment species formed with the potassium ions on the cleaved mica substrate dominated the positive secondary ion mass spectrum in the high-mass range. A temperature-dependent, ToF−SIMS study employing in situ heating of a 100% coverage OPA monolayer revealed that the molecules begin to diffuse above ∼80 °C, resulting in a decrease in the relative secondary ion yield of the OPA-specific secondary ions. This observation is hypothesized to be due to a decrease in the effective coverage of the substrate by the OPA molecules, which in turn could be due to the formation of multilayers upon heating in an effort to minimize the energy of the system. The interesting behavior of the novel OPA dimer species as a function of temperature is also reported. It was observed that the relative intensity of OPA and the mica-specific secondary ion peak intensities to that of Si (mica substrate) provides an effective means to estimate the change in coverage at elevated temperatures.

As determined by scratch tests, self-assembled monolayers (SAMs) of octadecylphosphonic acid (OPA) on a muscovite mica substrate were found to be mechanically robust and to serve as a lubricant to protect the underlying mica substrate. For comparison purposes, three polymer films were subjected to scratch tests under the same conditions. The scratch tests were conducted using a diamond-tipped stylus, and the resultant scratches were examined using atomic force microscopy. The excellent mechanical strength of OPA SAMs is supported by analysis with time-of-flight secondary ion mass spectrometry, which suggests that the headgroup of the OPA is strongly bonded to the substrate atoms. The molecular lubrication provided by OPA SAMs suggests that the interaction between the headgroup and the substrate is sufficiently strong to endure significant shear force and that the hydrocarbon chains are able to dissipate shear energy.

Summary The Green’s function is derived for the bending problem of an unsymmetrical laminated infinite plate with bending-extension coupling. The plate contains a traction-free elliptic hole and is subjected to concentrated loads, particularly a normal point force. The modified complex-potential approach developed earlier for unsymmetrical laminated plates is applied in the investigation. The techniques of conformal mappings and Cauchy integral over the boundaries are used to derive the closed-form complex stress function.

The kinetics of the disorder−order transition (ODT) in a triblock of polystyrene (PS) and poly(ethylene-co-butylene) (PEB), in mineral oil, a selective solvent for the middle PEB block, was followed by time-resolved SAXS using both temperature ramp and rapid temperature quench techniques. Data analysis, using the Percus−Yevick interacting hard-sphere model plus Gaussians for the Bragg peaks in the ordered body-centered-cubic (bcc) state, shows that the core radius Rc, the hard-sphere volume fraction φ, and their interaction radius Rhs increased with decreasing temperature in the disordered state. At the ODT, φ reaches a maximum and Rc and φ change on ordering. The kinetics exhibits two stages corresponding to temperature equilibration and supercooling of the micellar fluid followed by nucleation and growth of the ordered state. The induction time for the onset of the second stage shows a minimum around the glass transition of the polystyrene cores.

We have used small‐angle x‐ray scattering (SAXS), and small‐angle neutron scattering (SANS) to study the micelle structure of a polystyrene‐block‐poly(ethene‐co‐butene)‐block‐polystyrene triblock copolymer in dilute ‐ semidilute solutions in solvents selective for either the outer styrene block (dioxane) or for the middle block (heptane or tetradecane). Measurements of equilibrium structure factors showed that micelles were formed in both types of selective solvents. In the case of dioxane, the micelles are isolated whereas in the case of heptane or tetradecane, a bridged micellar structure may be formed at higher copolymer concentrations. In both cases we observed an ordered cubic structure of insoluble domains (micellar cores) at high concentrations (> 8 %). The micellar scattering function was fit to the Percus‐Yevick interacting hard‐sphere model. The temperature dependence of the core radius, the hard‐sphere interaction radius and the volume fraction of hard spheres were obtained. We also used synchrotron‐based time‐resolved SAXS to examine the kinetics of ordering of the micelles on a cubic lattice for many different temperature jumps into the ordered cubic phase starting from the disordered micellar fluid phase in different solvents at different concentrations. The time evolution of the structure changes was determined by fitting the data with Gaussians to describe the structure factor of the ordered Bragg peaks and the Percus‐Yevick structure factor was used to describe the micellar fluid. The time dependence of the peak intensities and widths as well as of the micellar parameters will be presented. The results showing the kinetics of the transformation from the fluid to the ordered phase were analyzed using the Mehl‐Johnson‐Avrami theory of nucleation.

The morphology of a surface imaged by dynamic force mode atomic force microscopy is obtained through an interaction between the probe tip and surface features. When the tip is contaminated and the size of the contaminant is comparable to the size of the features on the sample surface, artifacts attributable to the contaminant are observed to dominate the image. To reduce the possibility of effects from such artifacts, the tip performance should be checked by scanning a reference sample of known surface morphology. We demonstrate a simple and effective method of evaluating tip performance by the imaging of a commercially available biaxially oriented polypropylene (BOPP) film, which contains nanometer-scale-sized fibers. This sample is appropriate for use as a reference because a contaminated tip will not detect the fiberlike network structure. In addition, BOPP has a soft, highly hydrophobic surface of low surface energy, thus ensuring that the tip will not be damaged or contaminated during the evaluation process.

Localized shear deformation of biaxially oriented polypropylene (PP) film using a stylus force of 0.4 mN results in a reorientation of polymer strands in the shear-force direction, which appears as a striped region. This change in surface structure, which was observed by atomic force microscopy (AFM), resulted in an increase in the adhesion force as determined from the interaction between the AFM tip and the sample surface. This increase in adhesion force results from an increase in surface energy, which is thought to be caused by an increase in density and closer ordering of the polymer strands on the film surface. We demonstrate that the surface energy of PP film can be increased either by this mechanical scratching on the surface or by adding oxidation-induced chemical functional groups to the surface. The increase in surface energy from mechanical scratching of the PP surface is comparable to that introduced by surface oxidation of the unscratched PP surface after 1-min UV/ozone exposure.

The effects of subsampling and of the variation within and among sampling stations on the accuracy of the estimates of mean population densities for copepods and cladocerans are examined. For the computation of the coefficient of variation in the mean, the sample variance of log transformed data is appropriate. Accuracy is primarily influenced by variation between sampling stations and to a lesser extent by the variation within a sampling station, while subsampling variation has only a minor effect on the accuracy as long as more than 25 individuals per subsample are counted.

Resistance to virus infections in higher vertebrates is mediated in part through catalysis of RNA decay by the, interferon-regulated 2-5A system. A functional 2-5A system requires two enzymes, a 2-5A synthetase that produces 5'-phosphorylated, 2',5'-linked oligoadenylates (2-5A) in response to double-stranded RNA, and the 2-5A-dependent RNase L. We have coexpressed these human enzymes in transgenic tobacco plants by using a single plasmid containing the cDNAs for both human RNase L and a low molecular weight form of human 2-5A synthetase under control of different, constitutive promoters. Expression of the human cDNAs in the transgenic plants was demonstrated from Northern blots, by specific enzyme assays, and by immunodetection (for RNase L). Infection of leaves, detached or in planta, of the coexpressing transgenic plants by tobacco mosaic virus, alfalfa [correction of alfafa] mosaic virus, or tobacco etch virus resulted in necrotic lesions. In contrast, leaves expressing 2-5A synthetase or RNase L alone and leaves containing the plasmid vector alone produced typical systemic infections. While alfalfa mosaic virus produced lesions only in the inoculated leaves regardless of the concentration of virus in the inoculum, high, but not low, levels of tobacco etch virus inoculum resulted in escape of virus to uninoculated leaves. Nevertheless, there was a substantial reduction of tobacco etch virus yield as measured by ELISA assay in the coexpressing transgenic plants. These results indicate that expression of a mammalian 2-5A system in plants provides resistance to virus infections.

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The stomach contents of 517 eels were analysed during 1979. In that particular year the diet consisted predominantly of chironomids, but large bivalve molluscs were of secondary importance. The meaning of this observation is discussed in relation to food conditions and the food preference of the eel.

The influence of thermal discharge from a 640 MW steam electric power station on the Bergumermeer (shallow, eutrophic lake) was investigated. The temperature of the thermal effluent did not exceed 30 °C. The lake was sampled extensively from 1975 to 1978. Zooplankton densities at different depths in the heated and non-heated parts of the lake were compared. A vital staining technique was used to assess entrainment mortality of cladocerans. The entrainment mortalities for the most abundant cladocerans were only 2 to 3% but for Leptodora kindtii 19% and about 25% for Diaphanosoma brachyurum, Ceriodaphnia pulchella and the cyclopoid nauplii. The ecological consequences for the lake ecosystem are discussed.

N,N‘-Diarylureas were prepared, and the structure−activity relationship relative to the CXCR2 receptor was examined. This led to the identification of a potent and highly selective CXCR2 antagonist, which in addition was shown to be functionally active both in vitro against human neutrophils and in vivo in rabbit models of ear edema and neutropenia.

A resonant-cavity pin photodiode with two quantum dot absorbing regions is described. Each absorbing region consists of a stack of five self-assembled, quantum-dot layers, that are formed by the deposition of six monolayers of In0.5Ga0.5As, with GaAs spacer layers. To optimise the responsivity, the quantum dot stacks are placed at the antinodes of the cavity. The peak efficiency is 65% at 1.06 µm with a spectral bandwidth of 1.3 nm.

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