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High-energy and high-peak-power nanosecond pulse generation with beam quality control in 200-microm core highly multimode Yb-doped fiber amplifiers.

We explored high-energy and high-peak-power pulse generation in large-core multimode fiber amplifiers, achieving what is to our knowledge the highest reported energies, up to 82 mJ for 500-ns pulses, 27 mJ for 50-ns pulses, and 2.4-MW peak power for 4-ns pulses at 1064 nm, using 200-microm-diameter and 0.062-N.A. core Yb-doped double-clad fiber amplifiers. The highly multimode nature of the fiber core was mitigated by use of a coiling-induced mode-filtering effect to yield a significant improvement in output-beam quality from M2 = 25 from an uncoiled fiber to M2 = 6.5 from a properly coiled fiber, with the corresponding reduction in number of propagating transverse modes from > or = 200 to < or = 20.

Journal Article↗

Elastic fibers in scar tissue.

The capacity of the skin to be stretched and to return to its resting position is correlated to the quantity and to the quality of the elastic fiber network. Although elastic fibers have been demonstrated in scars, the time course of their appearance in scars and their role in scar elasticity has not been elucidated. A study was therefore undertaken to evaluate the elastic fiber network in scars. The scars studied were from re-excision specimens following a biopsy performed for a benign or a malignant process. A total of 182 scars were evaluated in patients of different age groups. Miller's elastic tissue stain, considered to be superior to Verhoeff's van Giesen stain, was used. No elastic fibers were detected in any of 116 scars which were of less than 3 months' duration. In 66 scars present for over 3 months, a progressive increase in elastic fibers was present, first as focal and thin fibers, then as diffuse and thicker fibers. For scars of the same duration, a regional difference was noted in that scars from the back contained more and thicker elastic fibers than those from the cheek. When patients were stratified according to age, no appreciable difference was noted in the density of elastic fibers in both new and old scars between the different age groups. These results show that the synthesis of elastic tissue fibers in scars is a function of duration and site of the scar.

Adolescent↗

Nutritional and physicochemical characteristics of dietary fiber enriched pasta.

The relationship between pasta texture and physicostructural characteristics was determined in relation to potential starch degradation and subsequent glucose release. Pastas with added soluble and insoluble dietary fiber ingredients were evaluated in relation to biochemical composition, cooking properties, and textural characteristics. Results show that both the type and amount of added fiber influence the overall quality of both raw and cooked pasta. Glucose release may be significantly reduced by the addition of soluble dietary fiber.

Cooking↗

Combinations of starch and digestible fiber in supplements for steers consuming a low-quality bromegrass hay diet.

Five steers (690 kg) with ruminal and duodenal cannulas were fed 100% bromegrass hay or 60% bromegrass hay:40% concentrate at 90% of their ad libitum DMI. The concentrate consisted of ground corn (GC) and(or) soybean hulls (SBH): 1) 100% SBH; 2) 66% SBH/33% GC; 3) 33% SBH/66% GC; or 4) 100% GC. Increasing level of corn inclusion decreased (linear, P < .01) DM and OM digestion (corrected for microbial DM and OM flow) in the rumen. Neutral detergent fiber digestion decreased in the rumen (quadratic, P = .05) and total tract (linear, P = .06) with increasing level of corn. Ruminal NDF digestion (quadratic, P = .05) and duodenal microbial N flow (quadratic, P < .01) were greatest for 66% SBH/33% GC, whereas total N flow to the duodenum was similar (P > .10) among treatments. Microbial efficiency increased (quadratic, P = .10) as the level of corn inclusion increased. Molar percentage of ruminal acetate decreased (linear, P < .01) with increasing level of corn, whereas molar percentage of butyrate increased (linear, P < .10). Carboxymethylcellulase activity was greatest (quadratic, P = .08) for 66% SBH/33% GC and paralleled NDF digestion in the rumen. Increasing level of corn decreased (linear, P < .07) in situ DM digestibility of SBH after 4, 8, and 12 h of incubation.

Ammonia↗

Production process of a new cellulosic fiber with antimicrobial properties.

The Lyocell process (system: cellulose-water-N-methylmorpholine oxide) of Zimmer AG offers special advantages for the production of cellulose fibers. The process excels by dissolving the most diverse cellulose types as these are optimally adjusted to the process by applying different pretreatment methods. Based on this stable process, Zimmer AG's objective is to impart to the Lyocell fiber additional value to improve quality of life and thus to tap new markets for the product. Thanks to the specific incorporation of seaweed, the process allows to produce cellulose Lyocell fibers with additional and new features. They are activated in a further step - by specific charging with metal ions - in order to obtain antibacterial properties. The favorable textile properties of fibers produced by the Lyocell process are not adversely affected by the incorporation of seaweed material or by activation to obtain an antibacterial fiber so that current textile products can be made from the fibers thus produced. The antibacterial effect is achieved by metal ion activation of the Lyocell fibers with incorporated seaweed, which contrasts with the antibacterial fibers known so far. Antibacterial fibers produced by conventional methods are in part only surface finished with antibacterially active chemicals or else they are produced by incorporating organic substances with antibacterial and fungicidal effects. Being made from cellulose, the antibacterial Lyocell fiber Sea Cell Active as the basis for quality textiles exhibits a special wear comfort compared to synthetic fibers with antibacterial properties and effects. This justifies the conclusion that the Zimmer Lyocell process provides genuine value added and that it is a springboard for further applications.

Anti-Infective Agents↗

Optimal dietary habits for the prevention of stroke.

Diet may influence stroke risk via several mechanisms, but the optimal dietary habits for stroke prevention are not well established. We reviewed English-language MEDLINE publications from January 1979 through November 2004 for experimental, observational, and clinical studies of dietary factors (minerals, fats, cholesterol, fish, animal protein, fiber, whole grains, carbohydrate quality, fruits and vegetables, antioxidants, B vitamins, dietary patterns) and risk of stroke or hypertension, the principal modifiable stroke risk factor. A total of 121 publications were selected based on relevance and quality of design and methods. Diets low in sodium and high in potassium lower blood pressure which will likely reduce stroke risk. Consumption of fruits and vegetables, whole grains, folate, and fatty fish are each likely to reduce stroke risk. A prudent or traditional Mediterranean dietary pattern, which incorporates these individual dietary components as well as intake of legumes and olive oil, may also prevent stroke. Evidence is limited or inconsistent regarding optimal levels of dietary magnesium, calcium, antioxidants, total fat, other fat subtypes, cholesterol, carbohydrate quality, or animal protein for stroke prevention. A diet low in sodium, high in potassium, and rich in fruits, vegetables, whole grains, cereal fiber, and fatty fish will likely reduce the incidence of stroke. Further research is needed regarding the possible effects of other major dietary factors on stroke risk.

Animals↗

Skin aging: lessons from cutis laxa and elastoderma.

Several lines of evidence suggest that elastic fibers provide resilience to normal human skin, and that abnormalities in elastin may be the primary event leading to the clinical appearance of aged skin. Innately aged skin exhibits a paucity and fragmentation of elastic fibers, while actinically damaged skin consists of an abnormal accumulation of elastotic material within the dermis. Cutis laxa and elastoderma are two cutaneous diseases that manifest as selective alterations in elastic fibers. Clinical and histopathologic findings in these diseases are similar to those found in cutaneous aging. Thus, it appears that alterations in the quantity and/or quality of the elastic fibers may contribute to age-associated cutaneous changes.

Adolescent↗

Responses of rat chorda tympani fibers to electrical stimulation of the tongue.

Responses of rat chorda tympani fibers to stimulations of the tongue with linearly rising anodal currents of varying rise rates and intensities, cathodal currents and chemical solutions representing the four basic taste qualities were obtained. Single fibers were classified into four types according to their response patterns to anodal and cathodal current stimulations of the tongue. Type A1 fibers responded only to an anodal current with both transient and steady response phases. Type A2 fibers responded only to an anodal current with only a steady response phase. Type B fibers responded to both anodal and cathodal currents. Type C fibers responded only to a cathodal current. Sensitivity to the rate f anodal current rise varied widely among individual chorda tympani fibers. The NaCl-sensitive fibers were most sensitive, the tartaric acid-sensitive fibers next, and the sucrose-sensitive fibers least. Fibers responding to cathodal current were sensitive to quinine hydrochloride. Fibers which showed rhythmic bursts of discharges in response to chemical stimuli also gave a similar discharge pattern in response to electrical stimulation.

Animals↗

Quality control analysis of the potential for asbestos contamination during tissue processing in pathology laboratories.

CONTEXT: Various quality assurance procedures are applied in pathology and analytical microscopy laboratories to ensure accurate results. OBJECTIVE: To assess the potential of cross-contamination of tissue with asbestos fibers and asbestos bodies during the fixation and washing process. DESIGN: Lung tissue from 10 patients with potential asbestos-related disease was evaluated. Samples of fixative, water, and lung tissue from each case were evaluated by light and analytical transmission electron microscopy for asbestos bodies and uncoated asbestos fibers. RESULTS: The lung samples tested contained a range of asbestos bodies and uncoated asbestos fibers. One wash water sample contained one asbestos body. No asbestos bodies or uncoated asbestos fibers were found in any other water or fixative samples. CONCLUSIONS: The absence of uncoated asbestos fibers in wash water or fixative samples argues that the fixation process stabilizes asbestos fibers within tissue and the protocol used in this pathology laboratory protects against cross-contamination of tissue. The finding of one asbestos body in one water sample further supports the efficiency of the protective controls used in the testing methods, since this asbestos body was in the external solution that was being discarded before tissue sampling occurred.

Aged↗

Reinforcement of tendons and ligaments with carbon fibers. Four years, 1300 cases.

Carbon fibers have a remarkable quality of compatibility with the ability to induce collagenous tissue, but the growth cannot be controlled and may be troublesome if excessive. Replacement of tendons and ligaments by carbon fibers requires a minimum of three months of immobilization, the time necessary for the newly formed tissue to be effective. It is possible if there is no other choice, as, for example, in surgery of old Achilles tendon ruptures, or in reconstruction of ligaments if all autogenous material has been used in previous operations. The author currently uses carbon fibers not to replace tendons or ligaments but to reinforce some weakness of their surgery. The technique of the reinforcement in surgery of the medical collateral ligament of the knee, in reconstruction of the medial patellar retinaculum, and in surgery of tendinitis of Achilles tendon or patellar ligament has been developed in the treatment of more than 1300 cases.

Achilles Tendon↗

Variation in output power of laser prostatectomy fibers: a need for power measurements.

OBJECTIVES: The aim of this study was the assessment of the quality of side-firing fibers that are being used for laser prostatectomy, either by a laser light transmission measurement or by visual inspection. METHODS: A power meter (Aquarius) was developed to measure the actual power transmitted through a side-firing fiber and delivered to the prostatic tissue. The power measurements were performed under clinical conditions, that is, under water and at relatively high input power. Furthermore, a protocol was developed for visual inspection of the fibers. Eight types of side-firing fibers were measured before use. Before and after a procedure, three fiber types were measured: ProLase II (28 samples), UltraLine (23 samples), and UroLase (44 samples). All these fibers were used in standard treatment protocols. RESULTS: At 60 W the transmission of new fibers (not used) ranged between 49% and 83% when compared to a bare fiber. After use, a large variation was found in transmitted power between different samples of one device. A correlation with total transmitted power was not present. At higher power input, vapor bubbles are generated at the tip of the fibers. Depending on the fiber design, these bubbles have a major impact on the transmission. Only for the UroLase fiber was there a significant correlation between visual inspection and the transmission of used samples at 10, 20, and 40 W. CONCLUSIONS: The transmission strongly varies between fibers and between different samples of one fiber during clinical use. Moreover, the transmission does not correlate with visual inspection. A power measurement during a clinical treatment will contribute to a more controlled procedure and to a better comparison of clinical laser prostatectomy studies.

Biophysical Phenomena↗

Soil quality: a review of the science and experiences in the USA.

An increasing human population is placing greater demand on soil resources, and as a result degradation is taking place in many regions of the world. This is critical because soils perform a number of essential processes including supporting food and fiber production, influencing air quality through interaction with the atmosphere, and serving as a medium for storage and purification of water. The soil quality concept was introduced to complement soil science research by making our understanding of soils more complete and helping guide the use and allocation of labor, energy, fiscal, and other inputs as agriculture intensifies and expands to meet increasing world demands. Soil quality thus provides a unifying concept for educating professionals, producers, and the public about the important processes that soils perform. It also provides an assessment tool for evaluating current management practices and comparing alternative management practices. Soil attributes comprising a minimum data set have been identified, and both laboratory and field methods have been developed for measuring them. A soil quality index is being developed to normalize measured soil quality indicator data and generate a numeric value that can be used to compare various management practices or to assess management-induced changes over time. Using previously published data, we evaluated the soil quality index as a tool to assess a wide range of management practices in the Northern Great Plains. The index ranked the treatments: grazed fertilized tame pasture > moderately grazed > ungrazed > heavily grazed > annual cropping with no-tillage > conventionally tilled crop-fallow which agrees with the way they were subjectively ranked in the publications. The soil quality index shows potential for use as a management assessment tool.

Agriculture↗

The addition of oat fiber and natural alternative sweeteners in the manufacture of plain yogurt.

Calorie-reduced yogurts that were fortified with 1.32% oat fiber were prepared from lactose-hydrolyzed milk, alone and supplemented with 2 and 4% sucrose or with 1.6, 3.6, and 5.5% fructose. Treated samples were compared with unsweetened yogurt and with yogurts sweetened with 2, 4, and 6% sucrose. Addition of 5.5% fructose increased fermentation time by 60%, slowing down the production of lactic, pyruvic, acetic, and propionic acids and the consumption of hippuric and orotic acids. Lactose hydrolysis had an inhibitory effect on starter activity at the beginning of fermentation and a stimulatory effect at the end of fermentation. Fiber addition led to increases in concentrations of acetic and propionic acid. Lactobacilli counts were lower in samples treated with fructose. The use of hydrolyzed milk had a stimulatory effect on total bacteria and lactobacilli counts throughout the cold storage period. After 28 d of storage, lactobacilli counts were consistently higher in fiber-fortified yogurts, but total bacteria counts were lower. Apparent viscosity increased with the addition of sweetener and fiber. Lactose-hydrolyzed and fructose yogurts had the highest viscosity values. Samples sweetened with sucrose received the highest scores for flavor. Fiber addition decreased overall flavor quality. The lactose-hydrolyzed yogurts received the highest flavor scores, independent of fiber fortification. Fiber addition improved the body and texture of unsweetened yogurts but lowered overall scores for body and texture in yogurts sweetened with sucrose.

Animals↗

Gustatory responsiveness of fibers in the hamster glossopharyngeal nerve.

1. Mammalian taste receptors are distributed within separate subpopulations, innervated by branches of cranial nerves VII, IX, and X. Most gustatory electrophysiology has focused on input from the fungiform papillae on the anterior portion of the tongue, carried by the chorda tympani branch of the VIIth nerve. However, only a small percentage of the taste buds are located in the fungiform papillae (approximately 18% in the hamster). There have been no studies on the hamster's IXth nerve, which innervates greater than 50% of its taste buds, and most other studies of IXth nerve function have employed only whole-nerve recording. 2. Action potentials were recorded from 83 individual fibers in the IXth nerve of the hamster. Stimuli were five concentrations each of sucrose, NaCl, HCl, and quinine hydrochloride (QHCl), all presented to every fiber at 37 degrees C. Responses were quantified as the number of impulses in 10 s minus the preceding 10 s of spontaneous activity. 3. Across these concentration series, HCl and QHCl were by far the most excitatory stimuli, with mean responses across all cells three to four times greater than those evoked by sucrose or NaCl. The order of effectiveness of the stimuli was H greater than Q much greater than N greater than S. 4. Of the 83 fibers, 56 were stimulated via the foliate papillae and 27 via the single vallate papilla. No fibers responded to both of these fields. There were generally no differences in the sensitivity of these two subpopulations of taste buds, except that QHCl was more effective when applied to the foliates. 5. A "total" response measure was derived by summing the excitatory responses to each stimulus across the entire concentration series. The fibers were then classified according to the best total response, resulting in 52 HCl-, 19 QHCl-, 8 sucrose- and 4 NaCl-best cells. Considering the slope of the concentration-response functions as a criterion for classification produced very similar results. The fiber classification varied somewhat with concentration, with more fibers categorized as HCl- and QHCl-best at the higher concentration levels. 6. Breadth of responsiveness was measured using the equation developed by Smith and Travers. At the concentrations used to examine hamster chorda tympani fibers, IXth nerve fibers were not very responsive and were quite narrowly tuned to the four taste qualities. At higher concentrations the fibers became more broadly responsive across the four stimuli.(ABSTRACT TRUNCATED AT 400 WORDS)

Action Potentials↗

[Types of coaptation of nerve fiber bundles and effectiveness of the nerve suture].

Experiments in 26 dogs were carried out in order to analyze the quality of comparing the nerve fiber bundles, morphometrical and functional parameters of regeneration after the restoration of the nerve with a standard epineural microsurgical suture and by an original method including the coaptation of the freshened ends by a relaxation transneural suture followed by epiperineural microneurorrhaphy. Five variants of the comparison of the nerve fiber bundles in the suture zone are described. The results of expert assessments and computed morphometry allowed to register higher indices of regeneration and differentiation of nerve fibers.

Animals↗

High-fiber diet in HIV-positive men is associated with lower risk of developing fat deposition.

BACKGROUND: Lipodystrophy has been described with increasing frequency in patients infected with HIV. This study focused on the identification of dietary components that may predispose HIV-positive patients to the development of fat deposition. OBJECTIVE: We evaluated differences in past dietary intake between men with HIV who developed fat deposition and those who did not. DESIGN: This nested case-control study consisted of 47 cases and 47 controls from the Nutrition for Healthy Living cohort. Food records from 6 to 24 mo before development of fat deposition in cases were analyzed and compared with food records from controls by using t tests for normally distributed nutrients and Wilcoxon rank-sum tests for nutrients with skewed distributions. RESULTS: HIV-positive patients without fat deposition had greater overall energy intakes (kcal/kg; P = 0.03) and greater intakes of total protein (P = 0.01), total dietary fiber (P = 0.01), soluble dietary fiber (P = 0.01), insoluble dietary fiber (P = 0.03), and pectin (P = 0.02) than did HIV-positive patients with fat deposition. Those without fat deposition also tended to currently perform more resistance training (P = 0.05) and to not be current smokers (P = 0.05). CONCLUSION: Our results indicate that an overall high-quality diet, rich in fiber and adequate in energy and protein, may be beneficial in preventing the development of fat deposition in persons infected with HIV. The results of this study further emphasize that a healthy lifestyle, including exercise and avoidance of unhealthy behaviors such as smoking, may also be similarly beneficial.

Adult↗

An analysis of hamster afferent taste nerve response functions.

Sensitivities to moderately intense stimuli representing four taste qualities to man were determined for 79 hamster chorda tympani fibers. Some fibers were very sensitive to sucrose, sodium chloride, or hydrochloric acid, but none were very sensitive to quinine. These sensitivities were not randomly distributed among fibers: the sucrose sensitivity was separated from and negatively correlated with the other sensitivities which were associated and positively correlated with each other. Moreover, there were a limited number of sensitivity patterns: (a) fibers responding best to sucrose responded second-best to salt, less to acid, not to quinine; (b) fibers responding best to salt either responded second-best to sucrose and not to acid or quinine; or second-best to acid, less to quinine, and not to sucrose; and (c) fibers responding best to acid responded second-best to salt, more to quinine, and less to sucrose than other fibers. Therefore, if four stimuli of different taste qualities are ordered from acceptable to unacceptable, neural response functions of most hamster chorda tympani taste fibers peak at one point. Sensitivities to nine other moderately intense stimuli which vary in quality to man were also determined for 46-49 of the fibers. Sensitivities to sweet stimuli were always associated with each other and separated from sensitivities to nonsweet stimuli. Sensitivities to nonsweet stimuli were all associated with each other; however, the strongest correlations were between sensitivities to stimuli of like quality, e.g., the three acids or the two sodium salts.

Animals↗