In the A2 experiment at the Mainz microtron (MAMI) electron accelerator, the production of nucleon resonances and light mesons off protons and nuclei using energy-tagged bremsstrahlung photons is ...studied. Decay products are measured with two electromagnetic calorimeters: Crystal Ball (CB), whose 672 NaI crystals cover almost the entire solid angle, and TAPS, which consists of 366 BaF2 and 72 PbWO4 crystals in the forward direction. Here, we report on the current performance and status of both detectors after 10 years of operation in Mainz. In addition, we present the new CB high-voltage system, a new fast readout scheme for TAPS, and the planned upgrade of the CB data-acquisition system.
Optical absorption detection is the most common detection mode in capillary-based separation systems such as capillary liquid chromatography or capillary electrophoresis (CE). The peak-to-peak noise ...levels of presently available commercial absorbance detectors usable for on-column detection is of the range 1 × 10
−5 − 5 × 10
−5 absorbance units (10–50 μAU). Currently there is widespread interest in CE because of its simplicity and exceptional separation power. The most expensive item in a home-made CE set-up is the optical absorption detector. Herein we present a simple, versatile and inexpensive design for an on-column optical absorbance detector that is comparable in performance to commercial units in both ultraviolet and visible regions. The detector has been tested with Zn, Cd, and Hg lamps and a visible-light-emitting diode as the sources. Detector response is linear over several orders of magnitude. Noise levels are somewhat higher for the Hg lamp and ~15 μAU for the others for on-column detection through a 75 μm bore, 142 μm-diameter capillary. In actual CE experiments, the limit of detection for test solutes ranged from sub- to low-femtomole quantities.
Over the past years, antibiotic growth promoter had been restricted in animal husbandry production in many countries because of antimicrobial resistance and foodborne antibiotic residues. However, ...the problems of poor intestinal health and low growth efficiency of piglets have not been solved completely in an antibiotic-free diet, and it is urgent to explore alternatives to antimicrobial growth promoters.
Here, a total of 532 weaned pigs were assigned to one of 4 treatments, the low amino acid (AA) level diet (d 1 to d 14 is 1.35%, d 15 to d 42 is 1.25%) (Low AA), the low AA level diet supplementation with a carvacrol-thymol blend (50 mg carvacrol and 50 mg thymol/kg of diet) (CB) (Low AA+CB), the high AA level diet (d 1 to d 14 is 1.50%, d 15 to d 42 is 1.40%) (High AA), and the high AA level diet supplementation with a CB (High AA+CB), respectively. Then we measured growth performance and intestinal health indicators of weaned pigs.
Results showed that high AA level significantly reduced plasma urea nitrogen, plasma Interleukin-6 (IL-6) and fecal lipocalin-2 contents (P < 0.05), significantly increased the relative abundance of fecal Lactobacillus and Enterococcus, and had a trend to increase the fecal secretory immunoglobulin A (sIgA) and mucin 2 (MUC 2) contents (P < 0.05) in piglets, thereby alleviating the diarrhea of piglets and reducing the feed conversion ratio (FCR) of piglets during d 1~14 after weaning. Dietary supplementation with CB significantly increased the activity of plasma antioxidant enzymes T-SOD and GSH-px (P < 0.05), while significantly reduced plasma malondialdehyde (MDA), plasma interleukin-1β (IL-1β), plasma endotoxin and D-lactic acid contents (P < 0.05). Meanwhile, CB significantly decreased fecal lipocalin-2 contents and the abundance of fecal Escherichia coli (P < 0.05). Thus, we hypothesis that dietary supplementation with CB significantly increased the average daily gain (ADG) of piglets (P < 0.05) during d 1~14 after weaning through promoting intestinal health.
These results suggest that high AA level and dietary supplementation with CB improved the growth performance of weaned pigs in an antibiotic-free diet by improving AA metabolism and intestinal antioxidant capacity.
The SP2 high-performance switch STUNKEL, C. B; SHEA, D. G; STUCKE, R. F ...
IBM systems journal,
01/1995, Letnik:
34, Številka:
2
Journal Article
Recenzirano
The heart of an IBM SP2 system is the High-Performance Switch, which is a low-latency, high-bandwidth switching network that binds together RISC System/6000 processors. The switch incorporates a ...unique combination of topology and architectural features to scale aggregate bandwidth, enhance reliability, and simplify cabling. It is a bidirectional multistage interconnect subsystem driven by a common oscillator, and delivers both data and service packets over the same links. Switching elements contain a dynamically allocated shared buffer for storing blocked packet flits. The switch is constructed primarily from switching elements and adapters. The SP2 communication adapter uses a variety of techniques to improve bandwidth and offload communication tasks from the node processor.
The efficient activation and selective high-valent metal-oxo (HVMO) species generation remain challenging for peroxymonosulfate (PMS)-based advanced oxidation processes (PMS-AOPs) in water ...purification. The underlying mechanism of the activation pathway is ambiguous, leading to a massive dilemma in the control and regulation of HVMO species generation. Herein, bioinspired by the bio-oxidase structure of cytochrome P450, the axial coordination strategy was adopted to tailor a single-atom cobalt catalyst (CoN4S-CB) with an axial S coordination. CoN4S-CB high-selectively generated high-valent Co-Oxo species (Co(IV)=O) via PMS activation. Co(IV)=O demonstrated an ingenious oxygen atom transfer (OAT) reaction to achieve the efficient degradation of sulfamethoxazole (SMX), and this allowed robust operation in various complex environments. The axial S coordination modulated the 3d orbital electron distribution of the Co atom. Density functional theory (DFT) calculation revealed that the axial S coordination decreased the energy barrier for PMS desorption and lowered the free energy change (ΔG) for Co(IV)=O generation. CoN4S-PMS* had a narrow d-band close to the Fermi level, which enhanced charge transfer to accelerate the cleavage of O-O and O-H bonds in PMS. This work provides a broader perspective on the activator design with natural enzyme structure-like active sites to efficient activate PMS for selective HVMO species generation.
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•A bioinspired single-atom cobalt catalyst with an axial S coordination was prepared.•CoN4S-CB effectively activated PMS for selective Co(IV)=O generation.•Co(IV)=O demonstrated robust SMX degradation performance via OAT reaction.•The axial S coordination modulated the electron distribution of the Co 3d orbital.•Low energy barrier and high charge transfer favored O-O and O-H cleavage in PMS.
Diarylethene (DTE) has been widely used in fluorescence probes, molecular logic gates, optical data‐storage devices owing to the excellent photochromic property, while constructing high‐performance ...photochromic DTE in aqueous media remains a big challenge. Herein we present several host‐guest systems formed between cucurbitnuril (CBn, n=7, 8, 10) and two water‐soluble DTE derivatives 1 and 2. It was found that host‐guest interactions not only affect the photophysical properties of photochromic guests, but also make great differences on the photoreaction process. Different host‐guest binding behaviors also lead to different effects on the photochromic properties of guests. In the presence of CBn, both 1 and 2 showed enhanced emission and higher fluorescence quenching ratio at photostationary state. Besides, CB10⋅1 exhibited faster response rate in cyclization reaction and better photofatigue resistance than free 1 in aqueous solution, while the supramolecular assembly of (CB8)n⋅(2)n showed slower response rate in both directions of the reversible photoreaction. Besides, the photofatigue resistance of 2 can be greatly improved through binding with CB7. Our results suggest that host‐guest interactions could be an efficient way to improve photochromic properties of DTE in aqueous solution.
In the presence of CBn host, the photophysical and photochemical properties of diarylethene derivatives (DTEs) were significantly affected. With suitable CBn, DTEs showed faster response rate, better fatigue resistance, and higher fluorescence quenching ratio, suggesting that high‐performance photochromic system in aqueous solution can be constructed through CBn‐based host‐guest interactions.
Switch-based interconnects are used in a number of application domains, including parallel system interconnects, local area networks, and wide area networks. However, very few switches have been ...designed that are suitable for more than one of these application domains. Such a switch must offer both extremely low latency and very high throughput for a variety of different message sizes. While some architectures with output queuing have been shown to perform extremely well in terms of throughput, their performance can suffer when used in systems where a significant portion of the packets are extremely small. On the other hand, architectures with input queuing offer limited throughput or require fairly complex and centralized arbitration that increases latency. In this paper, we present a new input queue-based switch architecture called HIPIQS (HIgh-Performance Input-Queued Switch). It offers low latency for a range of message sizes and provides throughput comparable to that of output queuing approaches. Furthermore, it allows simple and distributed arbitration. HIPIQS uses a dynamically allocated multiqueue organization, pipelined access to multibank input buffers, and small cross-point buffers to deliver high performance. Our simulation results show that HIPIQS can deliver performance close to that of output queuing approaches over a range of message sizes, system sizes, and traffic. The switch architecture can therefore be used to build high performance switches that are useful for both parallel system interconnects and for building computer networks.
The objective of this study was to determine the effect of high stearic acid (SA) diets versus high polyunsaturated fatty acid (PUFA) diets on several measures of lipid peroxidation in vivo. ...Sprague-Dawley rats were fed diets that differed only in the fat source (8% by weight) for 19 weeks. High SA fats were beef tallow (BT) and cocoa butter (CB), high PUFA fats were soybean oil (SO) and menhaden oil (MO). Urine was analyzed for lipophilic aldehydes, the secondary products of lipid peroxidation, by HPLC. Decreases (P<0.05) were found for 4 nonpolar lipophilic aldehydes and related carbonyl compounds (NPC) and 4 polar lipophilic aldehydes and related carbonyl compounds (PC) when the BT-fed group was compared to the SO-fed group. Decreases were also found to be significant for total NPC (P<0.01) and total PC (P<0.05) between BT and SO-fed groups. Serum increase in resistance to oxidation (P<0.01) was found in the BT group when compared to the SO group. The differences in urine and serum measurements in the present experiment indicate lower level of lipid peroxidation in vivo due to the consumption of high SA containing BT diet compared to high PUFA containing SO diet without raising serum triglycerides and cholesterol levels significantly for the BT-fed groups.
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A facile and expandable methodology was successfully developed to fabricate laser-induced graphene from novel pristine aminated polyethersulfone (amPES) membranes. The as-prepared ...materials were applied as flexible electrodes for microsupercapacitors. The doping of amPES membranes with various weight percentages of carbon black (CB) microparticles was then performed to improve their energy storage performance. The lasing process allowed the formation of sulfur- and nitrogen-codoped graphene electrodes. The effect of electrolyte on the electrochemical performance of as-prepared electrodes was investigated and the specific capacitance was significantly enhanced in 0.5 M HClO4. Remarkably, the highest areal capacitance of 47.3 mF·cm−2 was achieved at a current density of 0.25 mA·cm−2. This capacitance is approximately 12.3 times higher than the average value for commonly used polyimide membranes. Furthermore, the energy and power densities were as high as 9.46 µWh·cm−2 and 0.3 mW·cm−2 at 0.25 mA·cm−2, respectively. The galvanostatic charge–discharge experiments confirmed the excellent performance and stability of amPES membranes during 5,000 cycles, where more than 100% of capacitance retention was achieved and the coulombic efficiency was improved up to 96.67%. Consequently, the fabricated CB-doped PES membranes offer several advantages including low carbon fingerprint, cost-effectiveness, high electrochemical performance and potential applications in wearable electronic systems.
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