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Sample records for pressure sores formation

  1. Pressure Sores

    MedlinePlus

    Pressure sores are areas of damaged skin caused by staying in one position for too long. They ... wheelchair, or are unable to change your position. Pressure sores can cause serious infections, some of which ...

  2. Skin (Pressure) Sores

    MedlinePlus

    ... Treatments and Side Effects Managing Cancer-related Side Effects Skin Problems Pressure Sores A skin or pressure sore ... Content Usage Policy . Skin Problems Dry Skin Itching Skin Color Changes Pressure Sores Scars ... and Paying for Treatment Treatments and Side Effects Survivorship: During and After Treatment Caregivers and Family ...

  3. Practical Management of Pressure Sores

    PubMed Central

    Jordan, John M.

    1992-01-01

    Pressure sores are common in the debilitated elderly. Causal factors are unrelieved pressure, shearing forces, friction, and moisture. Preventive measures should be used for all high-risk patients, defined by general condition, mental status, degree of incontinence, amount of activity, and mobility. Principles of treating ulcers include pressure relief, reducing bacterial counts, debriding necrotic tissue, and providing a moist, clean environment. Imagesp2385-ap2389-ap2392-a PMID:21221298

  4. Pressure sore risk assessment in children.

    PubMed

    Waterlow, J A

    1997-07-01

    A multi-centred study was undertaken involving 300 children ranging from neonates to children aged 16 years. The purpose of the study was to investigate the possibility of designing a pressure sore risk assessment scoring system suitable for the paediatric area of care. It was found that the following conclusions can be drawn: (i) Children are at risk of developing pressure sores; (ii) A version of the adult Waterlow card was not appropriate, especially at the younger end of the scale; (iii) There are identifiable situations and treatments which do pose a risk of pressure sore development. Admission documentation and a care plan within a hospital policy is recommended as the best method of drawing nurses' attention to the risk factors involved and the measures which need to be taken to alleviate the risk of tissue damage.

  5. Taking Care of Pressure Sores

    MedlinePlus

    ... way, you will rebuild your skin pressure tolerance. University of Washington-operated SCI Clinics: Harborview Medical Center ... Spinal Cord Injury Clinic nurses: 206-744-5862. University of Washington Medical Center Rehabilitation Medicine Clinic 1959 ...

  6. Pressure-induced referred pain is expanded by persistent soreness.

    PubMed

    Doménech-García, V; Palsson, T S; Herrero, P; Graven-Nielsen, T

    2016-05-01

    Several chronic pain conditions are accompanied with enlarged referred pain areas. This study investigated a novel method for assessing referred pain. In 20 healthy subjects, pressure pain thresholds (PPTs) were recorded and pressure stimuli (120% PPT) were applied bilaterally for 5 and 60 seconds at the infraspinatus muscle to induce local and referred pain. Moreover, PPTs were measured bilaterally at the shoulder, neck, and leg before, during, and after hypertonic saline-induced referred pain in the dominant infraspinatus muscle. The pressure and saline-induced pain areas were assessed on drawings. Subsequently, delayed onset muscle soreness was induced using eccentric exercise of the dominant infraspinatus muscle. The day-1 assessments were repeated the following day (day 2). Suprathreshold pressure stimulations and saline injections into the infraspinatus muscle caused referred pain to the frontal aspect of the shoulder/arm in all subjects. The 60-second pressure stimulation caused larger referred pain areas compared with the 5-second stimulation (P < 0.01). Compared with pressure stimulation, the saline-induced referred pain area was larger (P < 0.02). After saline-induced pain, the PPTs at the infraspinatus and supraspinatus muscles were reduced (P < 0.05), and the 5-second pressure-induced referred pain area was larger than baseline. Pressure pain thresholds at the infraspinatus and supraspinatus muscles were reduced at day 2 in the delayed onset muscle soreness side (P < 0.05). Compared with day 1, larger pressure and saline-induced referred pain areas were observed on day 2 (P < 0.05). Referred pain to the shoulder/arm was consistently induced and enlarged after 1 day of muscle soreness, indicating that the referred pain area may be a sensitive biomarker for sensitization of the pain system.

  7. Development of a cushion to prevent ischial pressure sores.

    PubMed Central

    Bowker, P; Davidson, L M

    1979-01-01

    A study was carried out jointly by nursing staff and technologists in an attempt to develop a cushion based on scientific principles and measurement that might prevent pressure sores. At each stage in the development clinical trials were carried out, and using the results of these together with the opinions of medical staff and patients who used the cushion the design was suitably modified. Over four years a seat was evolved that was simple to construct and fulfilled the clinical requirements for a wide range of patients while providing maximum relief of high-pressure points. The design was subsequently taken up commercially. Images Fig 3 PMID:509176

  8. Prevention is better than cure. A survey of the use of Pegasus Airwave System in pressure sore treatment.

    PubMed

    Winman, G; Ashley, L

    1992-12-01

    Pressure relieving mattresses play an important role in pressure sore prevention and healing. This study describes the current use and reported effectiveness of the Pegasus Airwave System in pressure sore prevention.

  9. Nutritional status, pressure sores, and mortality in elderly patients with cancer.

    PubMed

    Waltman, N L; Bergstrom, N; Armstrong, N; Norvell, K; Braden, B

    1991-07-01

    This prospective study aimed to determine differences in nutritional status, incidence of pressure sores, and incidence of mortality between two groups, one composed of 33 elderly, institutionalized patients with cancer and the other a matched group of 33 patients without cancer. Subjects with cancer were paired with subjects without cancer based on age (mean = 78), sex, and pressure sore risk. Skin breakdown, dietary intake, and blood and serum indices of nutritional status were studied for 12 weeks. Of the subjects with cancer, 85% developed pressure sores, compared to 70% of the subjects without cancer. Hemoglobin (Hgb) (female), serum total protein, total lymphocyte count, serum albumin, serum total iron binding capacity, and serum transferrin were significantly lower in subjects with cancer with pressure sores than in subjects without cancer with pressure sores. Total lymphocyte count and serum total protein were significantly lower in subjects with cancer with pressure sores than in subjects with cancer without pressure sores. Kwashiorkor was found in 70% of the subjects with cancer, compared to 21% of the subjects without cancer. During the study, 39% of the subjects with cancer and 15% of the subjects without cancer died. All 13 of the subjects with cancer who died had kwashiorkor and pressure sores and had died an average of three weeks after developing pressure sores. These results implicate that elderly patients with cancer who have protein deficiencies should be considered to be at risk of pressure sore development. Frequent repositioning and mattress overlays that reduce pressure and increase comfort may delay development of pressure sores.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. [The Development of a Care Protocol for Postoperative Pressure Sore Prevention].

    PubMed

    Huang, Yu-Ling; Lin, Hui-Ling; Wang, Fang; Wu, Shu-Fang Vivienne

    2015-12-01

    Pressure sores are a common complication caused by long periods of bed rest following major surgery. These sores may increase patient postoperative pain, increase the risk of infections, lengthen the pe-riod of hospitalization, and increase the duration and costs of nursing care. Therefore, maintaining the skin integrity of surgical patients is an important responsibility for operating room nurses and an indicator of nursing care quality. While pressure-sore risk assessment tools and interoperative strategies are available and used in foreign countries, there has been little related research conducted in Taiwan. After examining the relevant literature and considering the current postoperative pressure sore situation in Taiwan, the author developed a postoperative pressure sore care protocol as a reference for clinical staff. Protocol procedures include major breakthrough developments in areas such as post-survey risk assessment for pressure ulcers, pressure ulcer prevention strategies that take surgery-related risk factors into consideration, extra care and protection measures for surgical supine patients, and post-pressure sores. The developed postoperative pressure sore protocol may be incorporated into surgical care procedures during the post-surgical care period in order to effectively prevent the occurrence of post-surgery pressure ulcers. Furthermore, the developed protocol offers the potential to improve and strengthen the quality of surgical care in terms of both healthcare and post-surgical care.

  11. A new postoperative management scheme for preventing sacral pressure sores in patients with spinal cord injuries.

    PubMed

    Kato, H; Inoue, T; Torii, S

    1998-01-01

    Although the reliability of pressure sore surgery has improved with the advent of many different types of flaps, it is well known that the recurrence rate of pressure sores is still remarkably high in spinal cord-injured patients. This article reports the very low relapse rate of postsurgical pressure sores using air mattresses, which also helps relieve manpower requirements for care. We measured interface pressures at the sacrum for 18 spinal cord-injured patients with a ROHO air mattress (ROHO International, Inc, Belleville, IL). Based on the results, we used this mattress immediately after surgery for 19 spinal cord-injured patients with sacral pressure sores. Minimal repositioning was performed for each patient during the hospital stay. Minimal repositioning was similarly performed at home. All pressure sores healed, regardless of the type of surgical procedure, size, and degree of sore. No relapse has been found, with an average of 33.4 months after surgery. With this management, we could achieve a very low recurrence rate, require less manpower for postoperative management, as well as minimize stress for the patients.

  12. Detection and Isolation of Digital Dermatitis Treponemes from Bovine Pressure Sores.

    PubMed

    Clegg, S R; Crosby-Durrani, H E; Bell, J; Blundell, R; Blowey, R W; Carter, S D; Evans, N J

    2016-05-01

    Pressure sores cause severe pain and discomfort in hospitalized people and in farmed cattle and are often infected with unknown bacteria. Pressure sores occur on the upper legs of 6-10% of recumbent cattle and are generally considered to be caused by constant pressure, commonly on bony areas of the limbs. This study analyzed pressure sores taken from the upper limbs of 14 cattle using isolation in culture and nested polymerase chain reaction (PCR) to detect treponemes associated with digital dermatitis (DD). A 100% association of DD treponemes with the pressure sores was demonstrated, but treponemes were shown not to be part of the normal skin microbiota. Immunohistochemistry showed an association of DD treponemes with lesions and particularly with the hair follicles in lesions, identifying the bacteria deep within wounds, thereby suggesting that they could contribute to lesion pathogenesis. The bacteria isolated from the pressure sore lesions were similar or identical on analysis of the 16S rRNA gene to those found in DD foot lesions in cattle, suggesting the same bacteria can infect multiple lesions. Indeed, the results of this study suggest that these spirochaetal bacteria may be expanding in host range and in their ability to colonize different tissues and contribute to a range of disease manifestations in farm animals.

  13. An audit of pressure sores caused by intermittent compression devices used to prevent venous thromboembolism.

    PubMed

    Skillman, Joanna; Thomas, Sunil

    2011-12-01

    When intermittent compression devices (ICDs) are used to prevent venous thromboembolism (VTE) they can cause pressure sores in a selected group of women, undergoing long operations. A prospective audit pre and post intervention showed a reduced risk with an alternative device, without increasing the risk of VTE.

  14. Evaluating the effects of pentoxifylline administration on experimental pressure sores in rats by biomechanical examinations

    PubMed Central

    Velaei, Kobra; Torkman, Giti; Rezaie, Fatemealsadat; Amini, Abdollah; Noruzian, Mohsen; Tavassol, Azaedh; Bayat, Mehernoush

    2012-01-01

    This study used a biomechanical test to evaluate the effects of pentoxifylline administration on the wound healing process of an experimental pressure sore induced in rats. Under general anesthesia and sterile conditions, experimental pressure sores generated by no. 25 Halsted mosquito forceps were inflicted on 12 adult male rats. Pentoxifylline was injected intraperitoneally at a dose of 50 mg/kg daily from the day the pressure sore was generated, for a period of 20 days. At the end of 20 days, rats were sacrificed and skin samples extracted. Samples were biomechanically examined by a material testing instrument for maximum stress (N mm2), work up to maximum force (N), and elastic stiffness (N/mm). In the experimental group, maximum stress (2.05±0.15) and work up to maximum force (N/mm) (63.75±4.97) were significantly higher than the control group (1.3±0.27 and 43.3±14.96, P=0.002 and P=0.035, respectively). Pentoxifylline administration significantly accelerated the wound healing process in experimental rats with pressure sores, compared to that of the control group. PMID:23091522

  15. Multidisciplinary Approach to an Extended Pressure Sore at the Lumbosacral Area

    PubMed Central

    Yoon, Sehoon; Lázaro, Hudson Alex

    2016-01-01

    A pressure sore wound is often extensive or complicated by local infection involving adjacent soft tissue and bone. In this case, a regional flap after simple debridement is not adequate. Here, we present a case of an extensive pressure sore in the sacral area with deep tissue infection. A 43-year-old female patient with a complicated sore with deep tissue infection had a presacral abscess, an iliopsoas abscess, and an epidural abscess in the lumbar spine. After a multidisciplinary approach performed in stages, the infection had subsided and removal of the devitalized tissue was possible. The large soft tissue defect with significant depth was reconstructed with a free latissimus dorsi musculocutaneous flap, which was expected to act as a local barrier from vertical infection and provide tensionless skin coverage upon hip flexion. The extensive sacral sore was treated effectively without complication, and the deep tissue infection completely resolved. There was no evidence of donor site morbidity, and wheelchair ambulation was possible by a month after surgery. PMID:27896193

  16. [High-grade pressure sores in frail older high-risk persons. A retrospective postmortem case-control-study].

    PubMed

    Von Renteln-Kruse, W; Krause, T; Anders, J; Kühl, M; Heinemann, A; Püschel, K

    2004-04-01

    Some old persons at risk do develop, but others, at comparable risk, do not develop high-grade pressure sores. To evaluate potentially different risk factors, we performed a post mortem case-control study in old persons who developed high-grade pressure sores within six months until 14 days before death. Consecutive cases with pressure sores grade >/=3 and potential controls at comparably high risk for pressure sores were examined before cremation. After written informed consent had been obtained by the next relatives, all available nursing and medical records of the deceased were thoroughly evaluated. Cases and controls were matched according to age, gender, immobility, and cachexia.A total of 100 cases with 71 pressure sores grade 3 and 29 pressure sores grade 4 were compared to 100 controls with 27 pressure sores grade pressure sores in frail older high-risk persons. Sedative drug effects and impaired patient compliance with preventive and therapeutic measures may also be associated with the development of high-grade pressure sores in old persons at high risk.

  17. The safety and effect of topically applied recombinant basic fibroblast growth factor on the healing of chronic pressure sores.

    PubMed Central

    Robson, M C; Phillips, L G; Lawrence, W T; Bishop, J B; Youngerman, J S; Hayward, P G; Broemeling, L D; Heggers, J P

    1992-01-01

    The first randomized, blinded, placebo-controlled human trials of recombinant basic fibroblast growth factor (bFGF) for pressure sore treatment were performed. Three different concentrations of bFGF in five dosing schedules were tested for safety using hematology, serum chemistries, urinalysis, absorption, antibody formation, and signs of toxicity. Efficacy was evaluated by wound volumes, histology, and photography. No toxicity, significant serum absorption, or antibody formation occurred. In six of eight subgroups, there was a trend toward efficacy with bFGF treatment. When all subgroups were combined, comparison of the slopes of the regression curves of volume decrease over initial pressure sore volume demonstrated a greater healing effect for the bFGF-treated patients (p < 0.05). Histologically, bFGF-treated wound sections demonstrated increased fibroblasts and capillaries. More patients treated with bFGF achieved > 70% wound closure (p < 0.05). Blinded observers were able to distinguish differences in visual wound improvement between bFGF and placebo groups. These data suggest that bFGF may be effective in the treatment of chronic wounds. PMID:1417189

  18. Design and research on reliability-validity for 3S intraoperative risk assessment scale of pressure sore.

    PubMed

    Gao, Xing-lian; Hu, Juan-juan; Ma, Qiong; Wu, He-yu; Wang, Zeng-yan; Li, Ting-ting; Shen, Jian-hui; Yang, Ying

    2015-04-01

    The reliability and validity of risk assessment scale (RAS) of pressure sore during 3S surgery were investigated. RAS of pressure sore was designed independently during 3S surgery. Five operating room nursing experts were selected to consult and detect face validity. Convenient and purposive sampling of 707 samples was conducted. Cronbach's alpha was used to measure content reliability and evaluate the internal consistence of RAS. The structural reliability was investigated by exploratory factor analysis method. The results showed that the content validity index was 0.92, and Cronbach's alpha of content reliability was 0.71. Structural validity, detected by Bartlett sphericity test, was 135.3 for 707 samples with the difference being statistically significant (P<0.01). KMO value was 0.729. The accumulative variance contribution ratio of common factor was 64.63%. The exploratory factor analysis showed the factor load of every clause was larger than 0.596. It was concluded that RAS of pressure sore for 3S surgery has better validity and reliability, and it could be used for evaluating and screening the high risk patients with pressure sores during surgery in order to efficiently reduce the occurrence of pressure sore during surgery. RAS of pressure sore for 3S surgery is worth to be popularized.

  19. Dual-dermal-barrier fashion flaps for the treatment of sacral pressure sores.

    PubMed

    Hsiao, Yen-Chang; Chuang, Shiow-Shuh

    2015-02-01

    The sacral region is one of the most vulnerable sites for the development of pressure sores. Even when surgical reconstruction is performed, there is a high chance of recurrence. Therefore, the concept of dual-dermal-barrier fashion flaps for sacral pressure sore reconstruction was proposed. From September 2007 to June 2010, nine patients with grade IV sacral pressures were enrolled. Four patients received bilateral myocutaneous V-Y flaps, four patients received bilateral fasciocutaneous V-Y flaps, and one patient received bilateral rotation-advanced flaps for sacral pressure reconstruction. The flaps were designed based on the perforators of the superior gluteal artery in one patient's reconstructive procedure. All flaps' designs were based on dual-dermal-barrier fashion. The mean follow-up time was 16 months (range = 12-25). No recurrence was noted. Only one patient had a complication of mild dehiscence at the middle suture line, occurring 2 weeks after the reconstructive surgery. The dual-dermal fashion flaps are easily duplicated and versatile. The study has shown minimal morbidity and a reasonable outcome.

  20. Pressure Sores

    MedlinePlus

    ... Diet Plans Nutrients and Nutritional Info Sugar and Sugar Substitutes Exercise and Fitness Exercise Basics Sports Safety Injury ... Diet Plans Nutrients and Nutritional Info Sugar and Sugar Substitutes Exercise and Fitness Exercise Basics Sports Safety Injury ...

  1. Pressure-time cell death threshold for albino rat skeletal muscles as related to pressure sore biomechanics.

    PubMed

    Linder-Ganz, Eran; Engelberg, Santiego; Scheinowitz, Mickey; Gefen, Amit

    2006-01-01

    Deep pressure sores (DPS) are associated with inadequate soft tissue perfusion and excessive tissue deformation over critical time durations, as well as with ischemia-reperfusion cycles and deficiency of the lymphatic system. Muscle tissue shows the lowest tolerance to pressure injuries, compared with more superficial tissues. In this communication, we present new histopathology data for muscle tissue of albino (Sprague-Dawley) rats exposed to pressures for 15 or 30 min. These data are superimposed with an extensive literature review of all previous histopathology reported for albino rat skeletal muscles subjected to pressure. The pooled data enabled a new mathematical characterization of the pressure-time threshold for cell death in striated muscle of rats, in the form of a sigmoid pressure-time relation, which extends the previous pressure-time relation to the shorter exposure periods. We found that for pressure exposures shorter than 1 h, the magnitude of pressure is the important factor for causing cell death and the exposure time has little or no effect: even relatively short exposures (15 min - 1 h) to pressures greater than 32 kPa (240 mmHg) cause cell death in rat muscle tissue. For exposures of 2 h or over, again the magnitude of pressure is the important factor for causing cell death: pressures greater than 9 kPa (67 mmHg) applied for over 2 h consistently cause muscle cell death. For the intermediate exposures (between 1 and 2 h), the magnitude of cell-death-causing pressure strongly depends on the time of exposure, i.e., critical pressure levels drop from 32 to 9 kPa. The present sigmoidal pressure-time cell death threshold is useful for design of studies in albino rat models of DPS, and may also be helpful in numerical simulations of DPS development, where there is often a need to extrapolate from tissue pressures to biological damage.

  2. [A double blind randomised clinical trial to assess the efficacy of the treatments of the superficial pressure sores].

    PubMed

    Di Giulio, Paola; Saiani, Luisa; Laquintana, Dario; Palese, Alvisa; Perli, Serena; Andreatta, Mariarosa; Rosa, Federica; Chini, Patrizia; Soraperra, Francesca; Ventura, Ida; Suriani, Cinzia; Romani, Silvia; Zancarli, Miriam; Martini, Marta; Partel, Francesca; Bassetti, Serena; Kaisermann, Rita; Bortolotti, Chiara; Gianordoli, Mirta; Rizzoli, Ilaria; Nardelli, Roberta; Pellizzari, Enrico; Valduga, Edda; Castaman, Marta; Pordenon, Marta; Beltrame, Moira; Bertolo, Cecilia; Casasola, Eleonora; Del Pin, Patrizia; Giolo, Simonetta; Marcatti, Emanuele; Pecini, Dina; Rodaro, Marisa; Zanon, Cristina; Stefanon, Laura; Covre, Lidia; Babbo, Consuela; Martin, Irma; Roilo, Antonia; Zanutel, Marta; Sabbadin, Silvano; Boin, Laura; Caron, Alessia; Martignago, Egidio; Venturin, Valter; Greggio, Annalisa; Frigo, Paola; Lazzaron, Daniela; Tonietto, Annalisa; Zanin, Barbara; Zorzi, Silvano; Zuanon, Antonio; Salmaso, Daniele; Frison, Tiziana; Marin, Irene; Buosi, Antonella; Fiorese, Elena; Gasparin, Dino; Goat, Barbara; Saccardo, Graziella; Simonetto, Ornella; Gomiero, Silvio; Baccara, Nicoletta; Ghirardello, Lucia; Niolu, Marilena; Silvestri, Sabrina; Buffon, Maria Luisa; Casson, Paola; Santantonio, Rosy; Albore, Piersandro; Mazzorana, Elvira; Terziariol, Laura; Bulgarelli, Giuliana; Barani, Elisa; Gasparini, Patrizia; Migliori, Salvina; Sasso, Elisa; Marfisi, Rosa Maria; Tognoni, Gianni; Sgaroni, Guya; Noro, Gabriele; Mattiuzzo, Mara

    2004-01-01

    In spite of the progresses of knowledge and care, pressure sores continue to be a clinically relevant problem. A double blind randomised controlled trial was organised to assess the efficacy of triticum vulgaris (Fitostimoline) vs placebo in the re-epithelisation of superficial pressure sores. Patients with stage NPUAP II or superficial pressure sores, with an expected survival of more than 3 months and eligible for a follow-up up to 8 weeks were included, over a period of 2 years in 46 clinical sites. The protocol was approved by local ethical committees and informed consent was obtained before randomisation. Medications were performed by nurses if the patient was hospitalised and by nurses or properly instructed caregivers at home. Weekly follow-up controls were assumed by nurses. Out of the 294 randomised patients 270 were included in the analyses. The two groups are comparable for the main characteristics except for Norton Scale mean values, less severe in the group assigned to active treatment (10.1+/-3.7 vs 8.9+/-3.2). The mean follow-up was of 3.8 and 4.2 weeks with a mean duration of 26+/-18 and 29+/-18 days for the experimental group and controls respectively. Seventy-six patients in the treatment group and controls (58.0 and 54.7) had their lesions re-epithelized. Adjusting results for age, initial Norton and Push scores there are no differences between treated and controls (OR 0.99 95% IC 0.60-1.67). This multicentre study, sponsored by a research group of nurses, failed to support the hypothesis that triticum vulgaris, the active component of the product Fitostimoline, given on top of recommended treatment, provides a specific therapeutic advantage in terms of frequency and timing of re-epithelization in superficial pressure sores.

  3. Canker Sores

    MedlinePlus

    Canker sores are small, round sores in your mouth. They can be on the inside of your cheek, under your tongue, or in the back of your throat. They usually have a red edge and a gray center. They can be quite painful. They are ...

  4. Mouth Sores

    MedlinePlus

    ... contains fluoride. Note that whitening toothpastes may contain hydrogen peroxide, which can irritate sore mouths. Remove and clean ... mixed with 2 cups water or 1 teaspoon salt and 1 teaspoon baking soda mixed with 1 ...

  5. Cold Sore

    MedlinePlus

    ... packaged as pills to be swallowed. Others are creams to be applied to the sores several times ... In general, the pills work better than the creams. For very severe infections, some antiviral drugs can ...

  6. Old age, malnutrition, and pressure sores: an ill-fated alliance.

    PubMed

    Mathus-Vliegen, Elisabeth M H

    2004-04-01

    Wound healing is a complex, tightly regulated process, consisting of three distinct phases. In each phase of wound healing, energy and macronutrients are required. Moreover, animal studies have established a specific role for certain nutrients such as the amino acid arginine, the vitamins A, B, and C, and the elements selenium, manganese, zinc, and copper. Chronic wounds such as pressure ulcers have extensively been investigated as to the risk of development, prevention, and cure. Here, the combination of old age, malnutrition, and pressure ulcers is highly unfortunate. Energy and nutrients, such as proteins and vitamins B and C, being deficient at old age are needed in pressure ulcer healing. Malnutrition is associated with skin anergy and with immobility because of mental apathy and muscle wasting. Severe malnutrition, impaired oral intake, and the risk of pressure ulcer formation appear to be interrelated. Adequate nutrition may reverse the underfed state unless an underlying wasting disease was present and appeared to reduce the prevalence and incidence in cross-sectional and prospective observational studies. However, attempts to prevent pressure ulcers by nutritional intervention were divergent in outcome, reflecting the difficulties to meet the daily requirements in elderly persons and the lack of knowledge about true nutritional needs in wound healing. The consumption of a diet high in protein and energy may promote pressure ulcer healing. When considering nutritional support, oral supplementation should be weighted against tube feeding, as the associated morbidity of tube feeding, i.e., diarrhea, fecal incontinence, and restricted mobility being in themselves risk factors for pressure ulcers, might obscure the favorable effects of adequate nutrition. Despite the evidence in animal studies, none of the above-mentioned specific nutrients promoted the healing of pressure ulcers in humans. Therefore, the attention should be focused on early recognition of a

  7. Increased technetium uptake is not equivalent to muscle necrosis: scintigraphic, morphological and intramuscular pressure analyses of sore muscles after exercise

    NASA Technical Reports Server (NTRS)

    Crenshaw, A. G.; Friden, J.; Hargens, A. R.; Lang, G. H.; Thornell, L. E.

    1993-01-01

    A scintigraphic technique employing technetium pyrophosphate uptake was used to identify the area of skeletal muscle damage in the lower leg of four runners 24 h after an ultramarathon footrace (160 km). Most of the race had been run downhill which incorporated an extensive amount of eccentric work. Soreness was diffuse throughout the posterior region of the lower leg. In order to interpret what increased technetium uptake reflects and to express extreme endurance related damages, a biopsy was taken from the 3-D position of abnormal uptake. In addition, intramuscular pressures were determined in the deep posterior compartment. Scintigraphs revealed increased technetium pyrophosphate uptake in the medial portion of the gastrocnemius muscle. For 3698 fibres analysed, 33 fibres (1%) were necrotic, while a few other fibres were either atrophic or irregular shaped. A cluster of necrotic fibres occurred at the fascicular periphery for one subject and fibre type grouping occurred for another. Ultrastructural analysis revealed Z-line streaming near many capillaries and variously altered subsarcolemmal mitochondria including some with paracrystalline inclusions. The majority of the capillaries included thickened and irregular shaped endothelial cells. Intramuscular pressures of the deep posterior compartment were slightly elevated (12-15 mmHg) for three of the four subjects. Increased technetium uptake following extreme endurance running does not just reflect muscle necrosis but also subtle fibre abnormalities. Collectively, these pathological findings are attributed to relative ischaemia occurring during the race and during pre-race training, whereas, intramuscular pressure elevations associated with muscle soreness are attributed to mechanical stress caused by extensive eccentric work during the race.

  8. Comparison of fasciocutaneous V-Y and rotational flaps for defect coverage of sacral pressure sores: a critical single-centre appraisal.

    PubMed

    Djedovic, Gabriel; Metzler, Julia; Morandi, Evi M; Wachter, Tanja; Kühn, Shafreena; Pierer, Gerhard; Rieger, Ulrich M

    2017-03-06

    Pressure sore rates remain high in both nursing homes as well as in hospitals. Numerous surgical options are available for defect coverage in the sacral region. However, objective data is scarce as to whether a specific flap design is superior to another. Here, we aim to compare two fasciocutaneous flap designs for sacral defect coverage: the gluteal rotation flap and the gluteal V-Y flap. All primary sacral pressure sores of grades III-IV that were being covered with gluteal fasciocutaneous rotational or V-Y flaps between January 2008 and December 2014 at our institution were analysed. A total of 41 patients received a total of 52 flaps. Of these, 18 patients received 20 gluteal rotational flaps, and 23 patients received 32 V-Y flaps. Both groups were comparable with regards to demographics, comorbidities and complications. Significantly more V-Y flaps were needed to cover smaller defects. Mean length of hospital stay was significantly prolonged when surgical revision had to be carried out. Both flap designs have proven safe and reliable for defect coverage after sacral pressure sores. Gluteal rotational flaps appear to be more useful for larger defects. Both flap designs facilitate their reuse in case of pressure sore recurrence. Complication rates appear to be comparable in both designs and to the current literature.

  9. Progenitor cell therapy for sacral pressure sore: a pilot study with a novel human chronic wound model

    PubMed Central

    2014-01-01

    Introduction Chronic wounds are a major health-care issue, but research is limited by the complexity and heterogeneity in terms of wound etiology as well as patient-related factors. A suitable animal model that replicates the situation in humans is not available. Therefore, the aim of the present work is to present a standardized human wound model and the data of a pilot study of topically applied progenitor cells in a sacral pressure sore. Methods Three patients underwent cell harvest from the iliac crest at the time of the initial debridement. Forty-eight hours after bone marrow harvest and debridement, the CD34+ selected cell suspension was injected into the wound. With the aid of a laser scanner, three-dimensional analyses of wound morphometry were performed until the defect was reconstructed with a local flap 3 weeks after debridement. Results Decreases in volume to 60% ± 6% of baseline on the sham side and to 52% ± 3% of baseline on the cell side were measured. Histologic work-up revealed no signs of metaplastic, dysplastic, or neoplastic proliferation/differentiation after progenitor cell treatment. CD34+ cells were detected in the biopsies of day 0. Conclusions The pressure sore wound model allows investigation of the initial 3 weeks after cell-based therapy. Objective outcome analysis in terms of wound volume and histology can be performed without, or with, minimal additional morbidity, and the anatomy of the sacral area allows a control and study side in the same patient. Therefore, this model can serve as a standard for wound-healing studies. Trial registration ClinicalTrials.gov NCT00535548. PMID:24476740

  10. Cold Sores

    MedlinePlus

    ... causes oral herpes, or cold sores. Type 1 herpes virus infects more than half of the U.S. population by the time they reach their 20s. Type 2 usually affects the genital area Some people have no symptoms from the ...

  11. Doreen Norton OBE, MSc, SRN, FRCN (1922-2007): Pioneer who revolutionised pressure sore management and geriatric nursing to international acclaim.

    PubMed

    Denham, Michael J

    2016-05-01

    Doreen Norton was a delightful, widely respected nurse who devoted her life to improving the care of elderly people. She researched the neglected problem of pressure sores, revolutionised their nursing care, and thus achieved international fame. Her Pressure Sore Scale was established as a management tool and is still used today. She was a key member of the design team that produced the 'King's Fund Bed', researched equipment required on geriatric wards, assessed all geriatric long stay units in Scotland and established research as a valuable nursing tool within her profession and health authorities. She lectured extensively and her publications attracted worldwide acclamation. After her retirement, she was subsequently appointed to the world's first Chair of Gerontological Nursing in Cleveland, Ohio.

  12. Sore Throat: Treatment

    MedlinePlus

    Sore throat Treatment By Mayo Clinic Staff A sore throat caused by a viral infection usually lasts five to ... such children. Treating bacterial infections If your sore throat is caused by a bacterial infection, your doctor ...

  13. Bedsores (Pressure Sores)

    MedlinePlus

    ... possible to see how deep the wound is. Deep tissue injury A deep tissue injury may have the following characteristics: The ... a not-for-profit organization and proceeds from Web advertising help support our mission. Mayo Clinic does ...

  14. Preventing Pressure Sores

    MedlinePlus Videos and Cool Tools

    ... Question Videos by Family Relationship Videos by Experts Resources The Short List Government Programs Family and Caregiver ... by Family Relationship Videos by Spinal Cord Experts Resources Forums Peer Counseling Blog About Us Contact Donate ...

  15. Pressure induced polymerization of Formates

    NASA Astrophysics Data System (ADS)

    Tschauner, Oliver

    2004-03-01

    The discovery of pressure induced polymerization of CO2 inspired us to search for C-O based chain structures forming at high pressure. We used salts of carboxylic acids as starting materials and exposed them to pressures between 10 and 30 GPa. Upon heating to temperatures above 1800 K we observed deprotonation and significant changes in the Raman shifts of C-O streching modes. Structure analysis based on powder diffraction patterns collected at sector 16 of the APS showed formation of extended C-O chain structures with the cations of the salts residing in the interchain spaces. These new high pressure polymers are interesting by their mechanical strength and provide basic molecular patterns of organic metallic conductors.

  16. Pharyngitis - sore throat

    MedlinePlus

    Pharyngitis - bacterial; Sore throat ... caused by swelling in the back of the throat (pharynx) between the tonsils and the voice box (larynx). Most sore throats are caused by colds, the flu, coxsackie virus ...

  17. Sore Throat (For Parents)

    MedlinePlus

    ... 1- to 2-Year-Old First Aid: Sore Throat KidsHealth > For Parents > First Aid: Sore Throat A A A Sore throats are common at any age and can be ... They also can be caused by a strep throat infection, although this is rare in children younger ...

  18. Sore Throat (For Parents)

    MedlinePlus

    ... 1- to 2-Year-Old First Aid: Sore Throat KidsHealth > For Parents > First Aid: Sore Throat Print A A A Sore throats are common at any age and can be ... They also can be caused by a strep throat infection, although this is rare in children younger ...

  19. Heating tar sands formations while controlling pressure

    DOEpatents

    Stegemeier, George Leo [Houston, TX; Beer, Gary Lee [Houston, TX; Zhang, Etuan [Houston, TX

    2010-01-12

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

  20. Cold Sores (HSV-1)

    MedlinePlus

    ... A Week of Healthy Breakfasts Shyness Cold Sores (HSV-1) KidsHealth > For Teens > Cold Sores (HSV-1) A A A What's in this article? ... or around a person's lips, are caused by herpes simplex virus-1 (HSV-1) . But they don't ...

  1. Evaluation of the dynamic cutaneous post-ischaemic hyperaemia and thermal response in elderly subjects and in an area at risk for pressure sores.

    PubMed

    Schubert, V; Fagrell, B

    1991-03-01

    The response of skin blood cell flux (SBF) to locally applied pressure was evaluated with the laser-Doppler technique in the areas of the sacrum and the gluteus maximus muscle of geriatric patients and healthy young and elderly subjects. The SBF over the sacrum stopped at a lower external skin pressure than over the gluteus muscle in all groups studied (P less than 0.05-0.001). The SBF at rest was lower among geriatric patients and over the sacrum, with men showing the lowest value (P less than 0.001). The initial slope of the SBF curve and the peak SBF during the post-occlusive reactive hyperaemia (PRH) were lower among geriatric patients compared to younger healthy subjects (P less than 0.05-0.01) over both areas studied. During the last part of the PRH response rhythmic oscillations started, known as vasomotion. The mean skin temperature at rest was higher over the sacrum (P less than 0.001) than over the gluteus area, but no difference was found between the groups. The temperature increase during the PRH was larger over the gluteus muscle (P less than 0.01) than over the sacrum area in the healthy subjects. Among the patients the temperature increase was larger over the gluteus only during the first half of the PRH, after which the temperature increased most over the sacrum. It is concluded that SBF and skin temperature show different responses in microvascular reactivity to external pressure in elderly vs. younger subjects and also between sexes. The described technique may be useful in clinical practice for predicting the risk of pressure sores in different areas and subjects.

  2. Genital sores - female

    MedlinePlus

    ... painless sores. Less common infections such as chancroid , granuloma inguinale , molluscum contagiosum , and syphilis may also cause ... Elsevier; 2016:chap 16. Read More Chancroid Donovanosis (granuloma inguinale) Genital herpes Genital warts Melanoma Molluscum contagiosum ...

  3. Sore Throat: Symptoms and Causes

    MedlinePlus

    ... than two weeks Causes Viruses that cause the common cold and flu (influenza) also cause most sore throats. ... Viral illnesses that cause a sore throat include: Common cold Flu (influenza) Mononucleosis (mono) Measles Chickenpox Croup — a ...

  4. Canker Sores (For Parents)

    MedlinePlus

    ... open sores that have a white or yellowish coating and a red "halo" around them. They tend ... take you to a site outside of KidsHealth's control. About KidsHealth Nemours.org Reading BrightStart! Contact Us ...

  5. Canker Sores (For Parents)

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Canker ... > For Parents > Canker Sores Print A A A What's in ...

  6. Abnormally high formation pressures, Potwar Plateau, Pakistan

    USGS Publications Warehouse

    Law, B.E.; Shah, S.H.A.; Malik, M.A.

    1998-01-01

    Abnormally high formation pressures in the Potwar Plateau of north-central Pakistan are major obstacles to oil and gas exploration. Severe drilling problems associated with high pressures have, in some cases, prevented adequate evaluation of reservoirs and significantly increased drilling costs. Previous investigations of abnormal pressure in the Potwar Plateau have only identified abnormal pressures in Neogene rocks. We have identified two distinct pressure regimes in this Himalayan foreland fold and thrust belt basin: one in Neogene rocks and another in pre-Neogene rocks. Pore pressures in Neogene rocks are as high as lithostatic and are interpreted to be due to tectonic compression and compaction disequilibrium associated with high rates of sedimentation. Pore pressure gradients in pre-Neogene rocks are generally less than those in Neogene rocks, commonly ranging from 0.5 to 0.7 psi/ft (11.3 to 15.8 kPa/m) and are most likely due to a combination of tectonic compression and hydrocarbon generation. The top of abnormally high pressure is highly variable and doesn't appear to be related to any specific lithologic seal. Consequently, attempts to predict the depth to the top of overpressure prior to drilling are precluded.

  7. Factors in delayed onset muscular soreness of man.

    PubMed

    Bobbert, M F; Hollander, A P; Huijing, P A

    1986-02-01

    In this study 11 subjects performed exercise resulting in delayed onset muscular soreness in m. gastrocnemius with one leg, the experimental leg. The other leg served as control. Pre-exercise and 24, 48 and 72 h postexercise, soreness perception, resting EMG level of m. gastrocnemius, and volume and skin temperature of both legs were measured, and a leukocyte count was performed. Perception of soreness in m. gastrocnemius reported 24, 48, and 72 h postexercise was not accompanied by an increase in resting EMG level. This result indicates that soreness perception is not related to a tonic localized spasm in sore muscles. A rise in volume of the experimental leg relative to volume of the control leg was found 24, 48, and 72 h postexercise (P less than 0.05). It is suggested that the volume rise is due to edema formation in the experimental leg and that this edema formation is responsible for soreness perception. Since granulocytosis was not found, the hypothesis that edema formation reflects muscle inflammation is not substantiated.

  8. Factors in delayed muscle soreness.

    PubMed

    Abraham, W M

    1977-01-01

    The possible causes of delayed muscle soreness which occur 24 to 48 hr after exercise were examined from three different approaches, each designed to test an existing hypothesis. Surface electromyograms were used to evaluate the muscle spasm theory; the possibility of actual muscle cell damage was monitored by the presence of myoglobinuria, while the ratio of hydroxyproline/creatinine (OHP/Cr) in 24 hr urine collection was used as a marker for connective tissue involvement. In the first study, although all volunteers developed muscle soreness 24 and 48 hr after exercise, no change in the EMG activity of the sore muscles was observed. Myoglobin excretion was found in 88% of the subjects who developed soreness. However, in a second study, 92% of the subject who performed both moderate and heavy exercise but did not develop muscle soreness had myoglobinuria. In contrast, during a third experiment subjects on gelatin-free diets showed an increase (P less than .1) in the OHP/Cr between control (.020+/-.001) and 48 hr post-exercise (.002+/-.001, X+/-SE). Soreness resulted in all cases. When the OHP/Cr value is taken for the day of maximal soreness, the post-exercise mean increases to .024+/-.001 and the level of significance rises (P less than .005). These observations support the concept that exercise induced soreness may be related to disruption of the connective tissue elements in the muscle and/or their attachments.

  9. Herpes Simplex Virus (Cold Sores)

    MedlinePlus

    ... not always necessary. In these tests, a tissue scraping of the sores may be examined under the ... Academy of Pediatrics) The information contained on this Web site should not be used as a substitute ...

  10. Ram pressure induced star formation in Abell 3266

    NASA Astrophysics Data System (ADS)

    Bonsall, Brittany

    An X-ray observation of the merging galaxy cluster Abell 3266 was obtained via the ROSAT PSPC. This information, along with spectroscopic data from the WIde-field Nearby Galaxy-clusters Survey (i.e. WINGS), were used to investigate whether ram pressure is a mechanism that influences star formation. Galaxies exhibiting ongoing star formation are identified by the presence of strong Balmer lines (Hbeta), known to correspond to early type stars. Older galaxies where a rapid increase in star formation has recently ceased, known as E+A galaxies, are identified by strong Hbeta absorption coupled with little to no [OII] emission. The correlation between recent star formation and "high" ram pressure, as defined by Kapferer et al. (2009) as ≥ 5 x 10-11 dyn cm-2, was tested and lead to a contradiction of the previously held belief that ram pressure influences star formation on the global cluster scale.

  11. Basaltic Pressure Ridges: Formation and Relationship to Flow Emplacement

    NASA Technical Reports Server (NTRS)

    Theilig, E.

    1985-01-01

    Pressure ridges and pressure plateau are common but not ubiquitous surface features on terrestrial basaltic lava flows and may reflect a specific flow emplacement mechanism. Many of the ridges are large enough to be detected on high-resolution orbital images; therefore, understanding these features could provide a means for interpreting volcanic flows on the mechanism of pressure ridge formation and how their formation relates to flow emplacement. Results from detailed field studies indicate that pressure ridges and plateaus: (1) are emplaced as individual flow lobes, (2) can be composed of primary or secondary material, (3) are dependent on duration and volume of activity within the flow unit, (4) are penecontemporaneous in formation, and (5) are indicative of slowly advancing flows with numerous flow lobes continuously forming and overriding each other.

  12. Ozone formation in pulsed SDBD in a wide pressure range

    NASA Astrophysics Data System (ADS)

    Starikovskiy, Andrey; Nudnova, Maryia; mipt Team

    2011-10-01

    Ozone concentration in surface anode-directed DBD for wide pressure range (150 - 1300 torr) was experimentally measured. Voltage and pressure effect were investigated. Reduced electric field was measured for anode-directed and cathode-directed SDBD. E/n values in cathode-directed SDBD is higher than in cathode-directed on 50 percent at atmospheric pressure. E/n value increase leads to decrease the rate of oxygen dissociation and Ozone formation at lower pressures. Radiating region thickness of sliding discharge was measured. Typical thickness of radiating zone is 0.4-1.0 mm within pressure range 220-740 torr. It was shown that high-voltage pulsed nanosecond discharge due to high E/n value produces less Ozone with compare to other discharges. Kinetic model was proposed to describe Ozone formation in the pulsed nanosecond SDBD.

  13. Magnetically Orchestrated Formation of Diamond at Lower Temperatures and Pressures

    NASA Astrophysics Data System (ADS)

    Little, Reginald B.; Lochner, Eric; Goddard, Robert

    2005-01-01

    Man's curiosity and fascination with diamonds date back to ancient times. The knowledge of the many properties of diamond is recorded during Biblical times. Antoine Lavoisier determined the composition of diamond by burning in O2 to form CO2. With the then existing awareness of graphite as carbon, the race began to convert graphite to diamond. The selective chemical synthesis of diamond has been pursued by Cagniard, Hannay, Moisson and Parson. On the basis of the thermodynamically predicted equilibrium line of diamond and graphite, P W Bridgman attempted extraordinary conditions of high temperature (>2200°C) and pressure (>100,000 atm) for the allotropic conversion of graphite to diamond. H T Hall was the first to successfully form bulk diamond by realizing the kinetic restrictions to Bridgman's (thermodynamic) high pressure high temperature direct allotropic conversion. Moreover, Hall identified catalysts for the faster kinetics of diamond formation. H M Strong determined the import of the liquid catalyst during Hall's catalytic synthesis. W G Eversole discovered the slow metastable low pressure diamond formation by pyrolytic chemical vapor deposition with the molecular hydrogen etching of the rapidly forming stable graphitic carbon. J C Angus determined the import of atomic hydrogen for faster etching for faster diamond growth at low pressure. S Matsumoto has developed plasma and hot filament technology for faster hydrogen and carbon radical generations at low pressure for faster diamond formation. However the metastable low pressure chemical vapor depositions by plasma and hot filament are prone to polycrystalline films. From Bridgman to Hall to Eversole, Angus and Matsumoto, much knowledge has developed of the importance of pressure, temperature, transition metal catalyst, liquid state of metal (metal radicals atoms) and the carbon radical intermediates for diamond synthesis. Here we advance this understanding of diamond formation by demonstrating the external

  14. Pressure effect on soot formation in turbulent diffusion flames.

    PubMed

    Roditcheva, O V; Bai, X S

    2001-01-01

    Soot formation in a methane air turbulent jet diffusion flame is investigated numerically using a semi-empirical model. The temperature, density and species (the soot precursor C2H2) fields are calculated using detailed chemical kinetic mechanism based on the flamelet library approach. The influence of pressure on the soot formation and the behavior of the semi-empirical model in different flame situations are investigated. It is found that the flame shape and the flame temperature can be well predicted by the flamelet library approach. The calculated soot yield is mostly sensitive to the soot surface growth rate and the increase of pressure. The increase of pressure leads to the increase of soot surface growth rate and therefore to the increase of soot volume fraction. By adjusting a model constant in the soot surface growth rate, the soot emissions in both pressure p = 1 atm and p = 3 atm are properly simulated by the current semi-empirical soot model.

  15. How to care for pressure sores

    MedlinePlus

    ... blood flow, including diabetes or vascular disease Have Alzheimer disease or another condition that affects your mental state Have fragile skin Cannot control your bladder or bowels Do not get enough nutrition

  16. Pressure regimes and core formation in the accreting earth

    NASA Technical Reports Server (NTRS)

    Newsom, H. E.

    1992-01-01

    Recent work suggests that a large degree of melting is required to segregate metal from silicates, suggesting a connection with the formation of magma oceans. At low pressures metallic liquids do not wet silicate minerals, preventing the metal from aggregating into large masses that can sink. At high pressures, above 25 GPa, the dihedral angles of grains in contact with oxygen-rich metallic liquids may be reduced enough to allow percolation of metal, but this has not been confirmed. Physical models of core formation and accretion may therefore involve the formation of magma oceans and the segregation of metal at both high and low pressures. Models of core formation involving different pressure regimes are discussed as well as chemical evidence bearing on the models. Available geophysical data is ambiguous. The nature of the 670 km boundary (chemical difference or strictly phase change) between the upper and lower mantle is in doubt. There is some evidence that plumes are derived from the lower mantle, and seismic tomography strongly indicates that penetration of subducting oceanic crust into the lower mantle, but the tomography data also indicates that the 670 km discontinuity is a significant barrier to general mantle convection. The presence of the D' layer at the base of the lower mantle could be a reaction zone between the mantle and core indicating core-mantle disequilibrium, or D' layer could be subducted material. The abundance of the siderophile elements in the mantle could provide clues to the importance of high pressure processes in Earth, but partition coefficients at high pressures are only beginning to be measured.

  17. Radiolysis gas formation and pressure increase during a criticality excursion

    SciTech Connect

    Barbry, F.; Rozain, J.P.

    1989-01-01

    During a criticality excursion occurring in fissile solution, most of the energy released is transformed into thermal heating and the formation of gas by radiolytic decomposition of water. In addition, for fast kinetics excursions, a pressure increase in the internal solution is observed. This pressure increases and hydrogen generation can pose a safety concern. To understand and to model these phenomena, the Commissariat a l'Energie Atomique (CEA) Institute for Nuclear Protection and Safety has carried out specific experiments at the SILENE facility to: measure the pressure increase accompanying the power peak and determine the volume of radiolysis gas formed as a function of the energy and medium. These results are interrelated, and it should be possible to make use of pressure, energy, and radiolysis gas data to set up an equation of state of fissile solution and, consequently, to improve currently existing calculation models.

  18. Pressure regulates osteoclast formation and MCSF expression in marrow culture.

    PubMed

    Rubin, J; Biskobing, D; Fan, X; Rubin, C; McLeod, K; Taylor, W R

    1997-01-01

    One of the forces generated during skeletal loading is hydrostatic pressure. In the work presented here, the ability of increased pressure to influence recruitment of osteoclasts was evaluated. Murine marrow cultures, with pO2 and pCO2 kept constant, were subjected to either control (1.0 atm) or elevated (1.37 or 2.0 atm) hydrostatic pressure. As compared to control, cultures pressurized for 6 days at 1.37 atm formed less osteoclast-like cells (OCLC) (71 +/- 6% of control, P < 0.0001). A similar degree of inhibition occurred in cultures exposed to pressure during days 2-4 only (62 +/- 6%), while treatment during days 5-7 failed to inhibit the OCLC number relative to control (99 +/- 5%). Delivery of 2.0 atm pressure on days 2-4 generated 52 +/- 4% OCLC compared to control. Since macrophage colony stimulating factor (MCSF)-dependent proliferation of osteoclast precursors occurs during the pressure-sensitive period, semiquantitative RT-PCR for MCSF mRNA was performed after 3 days in 1.37 atm (days 2-4). As compared to controls, pressure caused a decrease in mRNA coding for the membrane bound form of MCSF (71.2 +/- 4% (n = 25, P < or = 0.05), while the MCSF RT-PCR product representing the secreted form showed no consistent change. This lack of response of the soluble MCSF RT-PCR product was expected, as levels of bioassayable MCSF were not altered by pressure. Extrapolating these data to in vivo conditions suggests that load-bearing will inhibit the formation of osteoclasts.

  19. Pressures in Tumuli: A Study of Tumuli Formation

    NASA Technical Reports Server (NTRS)

    Hansen, James E.

    2005-01-01

    Tumuli form via localized inflation in surface lava flows. These domed features have widths of 10-20 m, lengths of 10-150 m, and heights of 1-9 m. The axial fracture exposes a brittle crust overlying a ductilely deformed layer. The total crustal thickness is typically less than lm. Tumuli are observed on both terrestrial and martian lava flow surfaces, and provide insight on the flow formation processes and rates. Past studies have estimated the inflation pressure using a bending model for a circular, thin elastic plate, assuming small deflection (Rossi and Gudmundson, 1996). This formulation results in unrealistic pressures for some tumuli. We thus examine alternative models, including those with different shapes, bending of the ductile crust, large deflection, plastic deformation, and thick plate bending. Using the thickness of the ductile crust in the equations for thin, circular plates reduces most pressures to reasonable values. Alternative plate shapes do not cause a significant reduction in inflation pressure. Although the large deflection equations should be applicable based on the plate thickness to tumuli height ratios, they give even less realistic pressures. Tumuli with unrealistic pressures appear to have exceeded the critical bending moment, and have relatively thick crusts, requiring thick plate bending models.

  20. Interpreting fluid pressure anomalies in shallow intraplate argillaceous formations

    USGS Publications Warehouse

    Neuzil, Christopher E.

    2015-01-01

    Investigations have revealed several instances of apparently isolated highs or lows in pore fluid potential in shallow (< ~ 1 km depth) argillaceous formations in intraplate settings. Formations with the pressure anomalies are distinguished by (1) smaller ratios of hydraulic conductivity to formation thickness and (2) smaller hydraulic (or pressure) diffusivities than those without anomalies. This is consistent with transient Darcian flow caused by strain at rates of ~ 10−17 to 10-16 s-1, by significant perturbing events in the past 104 to 106 annum or by some combination of the two. Plausible causes include erosional downwasting, tectonic strain, and glaciation. In this conceptualization the anomalies provide constraints on formation-scale flow properties, flow history, and local geological forcing in the last 106 annum and in particular indicate zones of low permeability (10−19–10−22 m2) that could be useful for isolation of nuclear waste.

  1. Formation of silicon nanoparticles by a pressure induced nucleation mechanism

    NASA Astrophysics Data System (ADS)

    Kang, Myung-Koo; Kim, Si Joon; Kim, Hyun Jae

    2013-03-01

    Formation of silicon nanoparticles (SiNPs) was achieved using excimer laser crystallization of an amorphous Si (a-Si) thin film using a SiO2 capping layer (C/L) with improved thin-film transistor (TFT) performance due to the enlarged grain size of polycrystalline Si (poly-Si). After laser irradiation of an a-Si thin film covered with C/L, fluctuation in the surface morphology of the C/L was observed above the critical laser energy density (Ecr) with the formation of SiNPs. The grain size of the poly-Si layer after crystallization increased abruptly at the same time. A non-uniform pressure distribution beneath the SiO2 C/L was proposed for the initiation of nucleation, which is named pressure induced nucleation (PIN) mechanism. Following nucleation, the release of latent heat made it difficult for the remnant liquid Si to solidify and the volume increased due to the density difference between the liquid and solid Si. Consequently, the pressure on the liquid Si caused SiNPs to sprout through the SiO2 C/L as grains grew from the low temperature to high temperature point. This study offers not only a simple method to fabricate SiNPs with controllable size/density but also larger grain size with lower laser energy density, which leads to higher TFT performance.

  2. Neon-Bearing Ammonium Metal Formates: Formation and Behaviour under Pressure.

    PubMed

    Collings, Ines E; Bykova, Elena; Bykov, Maxim; Petitgirard, Sylvain; Hanfland, Michael; Paliwoda, Damian; Dubrovinsky, Leonid; Dubrovinskaia, Natalia

    2016-11-04

    The incorporation of noble gas atoms, in particular neon, into the pores of network structures is very challenging due to the weak interactions they experience with the network solid. Using high-pressure single-crystal X-ray diffraction, we demonstrate that neon atoms enter into the extended network of ammonium metal formates, thus forming compounds Nex [NH4 ][M(HCOO)3 ]. This phenomenon modifies the compressional and structural behaviours of the ammonium metal formates under pressure. The neon atoms can be clearly localised within the centre of [M(HCOO)3 ]5 cages and the total saturation of this site is achieved after ∼1.5 GPa. We find that by using argon as the pressure-transmitting medium, the inclusion inside [NH4 ][M(HCOO)3 ] is inhibited due to the larger size of the argon. This study illustrates the size selectivity of [NH4 ][M(HCOO)3 ] compounds between neon and argon insertion under pressure, and the effect of inclusion on the high-pressure behaviour of neon-bearing ammonium metal formates.

  3. FILAMENT FORMATION BY ESCHERICHIA COLI AT INCREASED HYDROSTATIC PRESSURES1

    PubMed Central

    Zobell, Claude E.; Cobet, Andre B.

    1964-01-01

    ZoBell, Claude E. (University of California, La Jolla), and Andre B. Cobet. Filament formation by Escherichia coli at increased hydrostatic pressures. J. Bacteriol. 87:710–719. 1964.—The reproduction as well as the growth of Escherichia coli is retarded by hydrostatic pressures ranging from 200 to 500 atm. Reproduction was indicated by an increase in the number of cells determined by plating on EMB Agar as well as by direct microscopic counts. Growth, which is not necessarily synonymous with reproduction, was indicated by increase in dry weight and protein content of the bacterial biomass. At increased pressures, cells of three different strains of E. coli tended to form long filaments. Whereas most normal cells of E. coli that developed at 1 atm were only about 2 μ long, the mean length of those that developed at 475 atm was 2.93 μ for strain R4, 3.99 μ for strain S, and 5.82 μ for strain B cells. Nearly 90% of the bacterial biomass produced at 475 atm by strain B was found in filaments exceeding 5 μ in length; 74.7 and 16.4% of the biomass produced at 475 atm by strains S and R4, respectively, occurred in such filaments. Strain R4 formed fewer and shorter (5 to 35 μ) filaments than did the other two strains, whose filaments ranged in length from 5 to >100 μ. The bacterial biomass produced at all pressures had approximately the same content of protein and nucleic acids. But at increased pressures appreciably more ribonucleic acid (RNA) and proportionately less deoxyribonucleic acid (DNA) was found per unit of biomass. Whereas the RNA content per cell increased with cell length, the amount of DNA was nearly the same in long filaments formed at increased pressure as in cells of normal length formed at 1 atm. The inverse relationship between the concentration of DNA and cell length in all three strains of E. coli suggests that the failure of DNA to replicate at increased pressure may be responsible for a repression of cell division and consequent filament

  4. Fluid pressure and reaction zone formation at a lithological interface

    NASA Astrophysics Data System (ADS)

    Malvoisin, Benjamin; Podladchikov, Yuri

    2014-05-01

    Chemical composition variations in reaction zones between two distinct lithologies are generally interpreted in terms of chemical potential gradients and diffusion process. Concentration profiles can then be used to quantify the species diffusion coefficients or the time scale of geological events. However, chemical potential gradients are also functions of temperature and pressure and local variations of these parameters can thus potentially modify the diffusion process. In northern Corsica, a centimeter scale reaction zone formed under blueschist conditions at a serpentinite - marble contact of sedimentary origin. Three sub-zones having chemical compositions evolving from one rock end-member to another divide the reaction zone along sharp interfaces. At the reaction zone - marble interface, marble decarbonation occurs to form wollastonite and carbonaceous matter. Thermodynamic calculations for this reaction and the respective increase in density of 25 % and 7 % in the bulk rock and in the garnet minerals are interpreted as records of a pressure gradient during reaction zone formation. Moreover, the formation of a volatile-free sub-zone in the reaction zone from reaction between the H2O-bearing serpentinite and the CO2-bearing marble released fluids at the contact. The impact of such a release on the fluid pressure was modelled by considering the effects of both the rock compaction and the transport of fluid by hydraulic diffusion. Modelling results indicates that > 0.5 GPa fluid overpressure can be generated at the contact if devolatilization rates are of the order of the one experimentally measured (> 10-5 kg of fluid/m3 of rock/s). The resulting pressure gradient is of the order of magnitude of the one necessary to counter-balance the effect on chemical potential of the chemical composition variations across the contact. Finally, after the reaction has run to completion, the model predicts that fluid rapidly diffuses away from the interface which thus stops

  5. Electrical characteristics and formation mechanism of atmospheric pressure plasma jet

    SciTech Connect

    Liu, Lijuan; Zhang, Yu; Tian, Weijing; Meng, Ying; Ouyang, Jiting

    2014-06-16

    The behavior of atmospheric pressure plasma jet produced by a coplanar dielectric barrier discharge in helium in external electrostatic and magnetic field is investigated. Net negative charges in the plasma jet outside the tube were detected. The deflection of the plume in the external field was observed. The plasma jet is suggested to be formed by the electron beam from the temporal cathode which is accelerated by a longitudinal field induced by the surface charges on the dielectric tube or interface between the helium and ambient air. The helium flow is necessary for the jet formation in the surrounding air.

  6. [Delayed post effort muscle soreness].

    PubMed

    Coudreuse, J M; Dupont, P; Nicol, C

    2004-08-01

    Muscle intolerance to exercise may result from different processes. Diagnosis involves confirming first the source of pain, then potential pathological myalgia. Delayed-onset muscle soreness (DOMS), commonly referred as tiredness, occurs frequently in sport. DOMS usually develops 12-48 h after intensive and/or unusual eccentric muscle action. Symptoms usually involve the quadriceps muscle group but may also affect the hamstring and triceps surae groups. The muscles are sensitive to palpation, contraction and passive stretch. Acidosis, muscle spasm and microlesions in both connective and muscle tissues may explain the symptoms. However, inflammation appears to be the most common explanation. Interestingly, there is strong evidence that the progression of the exercise-induced muscle injury proceeds no further in the absence of inflammation. Even though unpleasant, DOMS should not be considered as an indicator of muscle damage but, rather, a sign of the regenerative process, which is well known to contribute to the increased muscle mass. DOMS can be associated with decreased proprioception and range of motion, as well as maximal force and activation. DOMS disappears 2-10 days before complete functional recovery. This painless period is ripe for additional joint injuries. Similarly, if some treatments are well known to attenuate DOMS, none has been demonstrated to accelerate either structural or functional recovery. In terms of the role of the inflammatory process, these treatments might even delay overall recovery.

  7. SPECIFIC AND CROSS OVER EFFECTS OF MASSAGE FOR MUSCLE SORENESS: RANDOMIZED CONTROLLED TRIAL

    PubMed Central

    Sundstrup, Emil; Søndergaard, Stine D.; Behm, David; Brandt, Mikkel; Særvoll, Charlotte A.; Jakobsen, Markus D.; Andersen, Lars L.

    2014-01-01

    Purpose/Background: Muscle soreness can negatively interfere with the activities of daily living as well as sports performance. In the working environment, a common problem is muscle tenderness, soreness and pain, especially for workers frequently exposed to unilateral high repetitive movements tasks. The aim of the study is therefore to investigate the acute effect of massage applied using a simple device Thera‐band roller Massager on laboratory induced hamstring muscle soreness, and the potential cross over effect to the non‐massaged limb. Methods: 22 healthy untrained men (Mean age 34 +/− 7 years; mean height 181.7 +/− 6.9 cm; mean weight 80.6 +/− 6.4 kg; BMI: 24.5 +/− 1.3) with no prior history of knee, low back or neck injury or other adverse health issues were recruited. Participants visited the researchers on two separate occasions, separated by 48 hours, each time providing a soreness rating (modified visual analog scale 0‐10), and being tested for pressure pain threshold (PPT) and active range of motion (ROM) of the hamstring muscles. During the first visit, delayed onset muscular soreness of the hamstring muscles was induced by 10 x 10 repetitions of the stiff‐legged dead‐lift. On the second visit participants received either 1) 10 minutes of roller massage on one leg, while the contralateral leg served as a cross over control, or 2) Resting for 10 minutes with no massage at all. Measurement of soreness, PPT and ROM were taken immediately before and at 0, 10, 30 and 60 min. after treatment. Results: There was a significant group by time interaction for soreness (p < 0.0001) and PPT (p = 0.0007), with the massage group experiencing reduced soreness and increasing PPT compared with the control group. There was no group by time interaction for ROM (p = 0.18). At 10 min. post massage there was a significant reduction in soreness of the non‐massaged limb in the cross over control group compared to controls but this effect was lost 30

  8. Rare complication after VAC-therapy in the treatment of deep sore ulcers in a paraplegic patient.

    PubMed

    Citak, Mustafa; Backhaus, Manuel; Meindl, Renate; Muhr, Gert; Fehmer, Tobias

    2010-12-01

    The VAC-therapy is a safe, easy, and effective therapy for the management of chronic wounds. Known advantages of the VAC technique are the quicker wound healing by stimulating the blood flow, the formation of granulation tissue, angiogenesis, and cell proliferation. The use of negative pressure treatment can decrease the number of dressing changes and length of hospital stay. However, some related complications after and during VAC therapy have been described. We here describe a rare complication during the treatment of severe os ischium sore with VAC therapy, which has not been reported in the literature yet. We report about a 43-year-old paraplegic patient, referred to our clinic from a regional hospital where he had been admitted 2 months earlier, presenting with a necrotizing fasciitis after VAC therapy during the treatment of fourth grade os ischium sore. After operative debridement and long-term antibiotics with Ciprofloxacin soft tissue closure was performed using a myocutaneous tensor fascia lata flap. Temporary stabilization was achieved by a triangle external fixateur attached to the right femur and the pelvis. After 1 week the tapping point of the muscle flap could be covered with local skin mesh-graft from the right calf as a donor site. The patient was mobilized in a wheelchair and was discharged home 3 months after admission. The VAC technique is a safe, easy, and effective means in chronic wound care management. However, the described rare complication should be kept in mind. The clinical management of VAC therapy requires a distinct indication and close clinical monitoring by experienced medical professionals. The use of VAC therapy in fourth grade sores may have deleterious consequences for the patient.

  9. Perceived Muscle Soreness in Recreational Female Runners

    PubMed Central

    Burnett, D.; Smith, K.; Smeltzer, C.; Young, K.; Burns, S.

    2010-01-01

    The purpose of this study was to determine if rating of perceived exertion correlated with perceived muscle soreness during delayed onset muscle soreness (DOMS) in female runners. This study examined the pre and post running economy measures and perceived muscle soreness before and after a 30-min downhill run (DHR) at −15% grade and 70% of the subjects predetermined maximum oxygen uptake (VO2 peak). Six female recreational runners (mean age = 24.5) performed level running at 65%, 75%, and 85% of their VO2 peak prior to DHR (baseline economy runs), as well as, immediately following and 4 successive days after the DHR. Results: Subjective response related to perceived muscle soreness increased significantly from a mean of 2 (pre DHR) to 62 (2 days post DHR) on a scale of 1–100. Creatine kinase levels and oxygen consumption increased post DHR compared to pre DHR. Rating of perceived exertion did not change between the economy runs performed prior to or at any point after the DHR. Conclusion: Perceived muscle soreness is a better tool than the RPE scale to monitor exercise intensity for recreational female runners during periods of DOMS and running economy is adversely affected by DOMS. PMID:27182336

  10. The Role of Pressure in GMC Formation II: The H2-Pressure Relation

    NASA Astrophysics Data System (ADS)

    Blitz, Leo; Rosolowsky, Erik

    2006-10-01

    We show that the ratio of molecular to atomic gas in galaxies is determined by hydrostatic pressure and that the relation between the two is nearly linear. The pressure relation is shown to be good over 3 orders of magnitude for 14 galaxies, including dwarfs, H I-rich, and H2-rich galaxies, as well as the Milky Way. The sample spans a factor of 5 in mean metallicity. The rms scatter of individual points of the relation is only about a factor of 2 for all the galaxies, although some show much more scatter than others. Using these results, we propose a modified star formation prescription based on pressure determining the degree to which the ISM is molecular. The formulation is different in high- and low-pressure regimes, defined by whether the gas is primarily atomic or primarily molecular. This formulation can be implemented in simulations and provides a more appropriate treatment of the outer regions of spiral galaxies and molecule-poor systems, such as dwarf irregulars and damped Lyα systems.

  11. Carbon onions as nanoscopic pressure cells for diamond formation

    NASA Astrophysics Data System (ADS)

    Banhart, F.; Ajayan, P. M.

    1996-08-01

    SPHERICAL particles of carbon consisting of concentric graphite-like shells ('carbon onions') can be formed by electron irradiation of graphitic carbon materials1,2. Here we report that, when such particles are heated to ~700 °C and irradiated with electrons, their cores can be transformed to diamond. Under these conditions the spacing between layers in the carbon onions decreases from 0.31 in the outer shells (slightly less than the 0.34-nm layer spacing of graphite) to about 0.22 nm in the core, indicating considerable compression towards the particle centres. We find that this compression allows diamond to nucleate-in effect the carbon onions act as nanoscopic pressure cells for diamond formation.

  12. Carbonate formation in Wyoming montmorillonite under high pressure carbon dioxide

    SciTech Connect

    Hur, Tae-Bong; Baltrus, John P.; Howard, Bret H.; Harbert, William P.; Romanov, Vyacheslav N.

    2013-03-01

    Carbonation reaction with silicate minerals that are common components of the host rock and cap rock within geological storage reservoirs and the associated structural deformation were investigated for better understanding of the geochemical reactions associated with geologic CO2 storage. Exposure of a model expanding clay, Wyoming montmorillonite, SWy-2, to high-pressure CO2 resulted in the formation of a mineral carbonate phase via dry CO2–clay mineral interactions at two different temperatures. The experimental evidence suggests that the properties of CO2 fluid at 70 °C provide more favorable conditions for carbonate formation at the clay surface less accessible to CO2 at 22 °C. The carbonation reaction occurred predominantly within the first couple of days of exposure to the fluid and then proceeded slower with continuing exposure. As compared to the as-received clay under the same ambient conditions, the (0 0 1) basal spacing of the clay bearing carbonates (after the CO2 exposure) was slightly expanded at a relative humidity (RH) level of 12% but it was slightly collapsed at the RH level of 40%. Finally, experimental observations suggest that the carbonation reaction occurs at the external surface as well as internal surface (interlayer) of the clay particles.

  13. Controlling and assessing pressure conditions during treatment of tar sands formations

    DOEpatents

    Zhang, Etuan; Beer, Gary Lee

    2015-11-10

    A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the tar sands formation from a plurality of heaters located in the formation. Heat is allowed to transfer from the heaters to at least a portion of the formation. A pressure in the portion of the formation is controlled such that the pressure remains below a fracture pressure of the formation overburden while allowing the portion of the formation to heat to a selected average temperature of at least about 280.degree. C. and at most about 300.degree. C. The pressure in the portion of the formation is reduced to a selected pressure after the portion of the formation reaches the selected average temperature.

  14. Acute effects of massage or active exercise in relieving muscle soreness: randomized controlled trial.

    PubMed

    Andersen, Lars L; Jay, Kenneth; Andersen, Christoffer H; Jakobsen, Markus D; Sundstrup, Emil; Topp, Robert; Behm, David G

    2013-12-01

    Massage is commonly believed to be the best modality for relieving muscle soreness. However, actively warming up the muscles with exercise may be an effective alternative. The purpose of this study was to compare the acute effect of massage with active exercise for relieving muscle soreness. Twenty healthy female volunteers (mean age 32 years) participated in this examiner-blind randomized controlled trial (ClinicalTrials.gov NCT01478451). The participants performed eccentric contractions for the upper trapezius muscle on a Biodex dynamometer. Delayed onset muscle soreness (DOMS) presented 48 hours later, at which the participants (a) received 10 minutes of massage of the trapezius muscle or (b) performed 10 minutes of active exercise (shoulder shrugs 10 × 10 reps) with increasing elastic resistance (Thera-Band). First, 1 treatment was randomly applied to 1 shoulder while the contralateral shoulder served as a passive control. Two hours later, the contralateral resting shoulder received the other treatment. The participants rated the intensity of soreness (scale 0-10), and a blinded examiner took measures of pressure pain threshold (PPT) of the upper trapezius immediately before treatment and 0, 10, 20, and 60 minutes after treatment 48 hours posteccentric exercise. Immediately before treatment, the intensity of soreness was 5.0 (SD 2.2) and PPT was 138 (SD 78) kPa. In response to treatment, a significant treatment by time interaction was found for the intensity of soreness (p < 0.001) and PPT (p < 0.05). Compared with control, both active exercise and massage significantly reduced the intensity of soreness and increased PPT (i.e., reduced pain sensitivity). For both types of treatment, the greatest effect on perceived soreness occurred immediately after treatment, whereas the effect on PPT peaked 20 minutes after treatment. In conclusion, active exercise using elastic resistance provides similar acute relief of muscle soreness as compared with that using massage

  15. Delayed Onset Muscle Soreness After Inspiratory Threshold Loading in Healthy Adults

    PubMed Central

    Mathur, Sunita; Sheel, A. William; Road, Jeremy D.; Reid, W. Darlene

    2010-01-01

    Purpose: Skeletal muscle damage occurs following high-intensity or unaccustomed exercise; however, it is difficult to monitor damage to the respiratory muscles, particularly in humans. The aim of this study was to use clinical measures to investigate the presence of skeletal muscle damage in the inspiratory muscles. Methods: Ten healthy subjects underwent 60 minutes of voluntary inspiratory threshold loading (ITL) at 70% of maximal inspiratory pressure. Maximal inspiratory and expiratory mouth pressures, delayed onset muscle soreness on a visual analogue scale and plasma creatine kinase were measured prior to ITL, and at repeated time points after ITL (4, 24 and 48 hours post-ITL). Results: Delayed onset muscle soreness was present in all subjects 24 hours following ITL (intensity = 22 ± 6 mm; significantly higher than baseline p = 0.02). Muscle soreness was reported primarily in the anterior neck region, and was correlated to the amount of work done by the inspiratory muscles during ITL (r = 0.72, p = 0.02). However, no significant change was observed in maximal inspiratory or expiratory pressures or creatine kinase. Conclusions: These findings suggest that an intense bout of ITL results in muscle soreness primarily in the accessory muscles of inspiration, however, may be insufficient to cause significant muscle damage in healthy adults. PMID:20467514

  16. Vibration Therapy in Management of Delayed Onset Muscle Soreness (DOMS)

    PubMed Central

    Imtiyaz, Shagufta

    2014-01-01

    Both athletic and nonathletic population when subjected to any unaccustomed or unfamiliar exercise will experience pain 24-72 hours postexercise. This exercise especially eccentric in nature caused primarily by muscle damage is known as delayed-onset muscle soreness (DOMS). This damage is characterized by muscular pain, decreased muscle force production, reduce range of motion and discomfort experienced. DOMS is due to microscopic muscle fiber tears. The presence of DOMS increases risk of injury. A reduced range of motion may lead to the incapability to efficiently absorb the shock that affect physical activity. Alterations to mechanical motion may increase strain placed on soft tissue structures. Reduced force output may signal compensatory recruitment of muscles, thus leading to unaccustomed stress on musculature. Differences in strength ratios may also cause excessive strain on unaccustomed musculature. A range of interventions aimed at decreasing symptoms of DOMS have been proposed. Although voluminous research has been done in this regard, there is little consensus among the practitioners regarding the most effective way of treating DOMS. Mechanical oscillatory motion provided by vibration therapy. Vibration could represent an effective exercise intervention for enhancing neuromuscular performance in athletes. Vibration has shown effectiveness in flexibility and explosive power. Vibration can apply either local area or whole body vibration. Vibration therapy improves muscular strength, power development, kinesthetic awareness, decreased muscle sore, increased range of motion, and increased blood flow under the skin. VT was effective for reduction of DOMS and regaining full ROM. Application of whole body vibration therapy in postexercise demonstrates less pressure pain threshold, muscle soreness along with less reduction maximal isometric and isokinetic voluntary strength and lower creatine kinase levels in the blood. PMID:25121012

  17. Vibration Therapy in Management of Delayed Onset Muscle Soreness (DOMS).

    PubMed

    Veqar, Zubia; Imtiyaz, Shagufta

    2014-06-01

    Both athletic and nonathletic population when subjected to any unaccustomed or unfamiliar exercise will experience pain 24-72 hours postexercise. This exercise especially eccentric in nature caused primarily by muscle damage is known as delayed-onset muscle soreness (DOMS). This damage is characterized by muscular pain, decreased muscle force production, reduce range of motion and discomfort experienced. DOMS is due to microscopic muscle fiber tears. The presence of DOMS increases risk of injury. A reduced range of motion may lead to the incapability to efficiently absorb the shock that affect physical activity. Alterations to mechanical motion may increase strain placed on soft tissue structures. Reduced force output may signal compensatory recruitment of muscles, thus leading to unaccustomed stress on musculature. Differences in strength ratios may also cause excessive strain on unaccustomed musculature. A range of interventions aimed at decreasing symptoms of DOMS have been proposed. Although voluminous research has been done in this regard, there is little consensus among the practitioners regarding the most effective way of treating DOMS. Mechanical oscillatory motion provided by vibration therapy. Vibration could represent an effective exercise intervention for enhancing neuromuscular performance in athletes. Vibration has shown effectiveness in flexibility and explosive power. Vibration can apply either local area or whole body vibration. Vibration therapy improves muscular strength, power development, kinesthetic awareness, decreased muscle sore, increased range of motion, and increased blood flow under the skin. VT was effective for reduction of DOMS and regaining full ROM. Application of whole body vibration therapy in postexercise demonstrates less pressure pain threshold, muscle soreness along with less reduction maximal isometric and isokinetic voluntary strength and lower creatine kinase levels in the blood.

  18. A ram-pressure threshold for star formation

    NASA Astrophysics Data System (ADS)

    Whitworth, A. P.

    2016-05-01

    In turbulent fragmentation, star formation occurs in condensations created by converging flows. The condensations must be sufficiently massive, dense and cool to be gravitationally unstable, so that they start to contract; and they must then radiate away thermal energy fast enough for self-gravity to remain dominant, so that they continue to contract. For the metallicities and temperatures in local star-forming clouds, this second requirement is only met robustly when the gas couples thermally to the dust, because this delivers the capacity to radiate across the full bandwidth of the continuum, rather than just in a few discrete spectral lines. This translates into a threshold for vigorous star formation, which can be written as a minimum ram pressure PCRIT ˜ 4 × 10-11 dyne. PCRIT is independent of temperature, and corresponds to flows with molecular hydrogen number density n_{{H_2.FLOW}} and velocity vFLOW satisfying n_{{H_2.FLOW}} v_{FLOW}^2≳ 800 cm^{-3} (km s^{-1})^2. This in turn corresponds to a minimum molecular hydrogen column density for vigorous star formation, N_{{H_2.CRIT}} ˜ 4 × 10^{21} cm^{-2} (ΣCRIT ˜ 100 M⊙ pc-2), and a minimum visual extinction AV, CRIT ˜ 9 mag. The characteristic diameter and line density for a star-forming filament when this threshold is just exceeded - a sweet spot for local star formation regions - are 2RFIL ˜ 0.1 pc and μFIL ˜ 13 M⊙ pc-2. The characteristic diameter and mass for a prestellar core condensing out of such a filament are 2RCORE ˜ 0.1 pc and MCORE ˜ 1 M⊙. We also show that fragmentation of a shock-compressed layer is likely to commence while the convergent flows creating the layer are still ongoing, and we stress that, under this circumstance, the phenomenology and characteristic scales for fragmentation of the layer are fundamentally different from those derived traditionally for pre-existing layers.

  19. Formation of xenon-nitrogen compounds at high pressure

    PubMed Central

    Howie, Ross T.; Turnbull, Robin; Binns, Jack; Frost, Mungo; Dalladay-Simpson, Philip; Gregoryanz, Eugene

    2016-01-01

    Molecular nitrogen exhibits one of the strongest known interatomic bonds, while xenon possesses a closed-shell electronic structure: a direct consequence of which renders both chemically unreactive. Through a series of optical spectroscopy and x-ray diffraction experiments, we demonstrate the formation of a novel van der Waals compound formed from binary Xe-N2 mixtures at pressures as low as 5 GPa. At 300 K and 5 GPa Xe(N2)2-I is synthesised, and if further compressed, undergoes a transition to a tetragonal Xe(N2)2-II phase at 14 GPa; this phase appears to be unexpectedly stable at least up to 180 GPa even after heating to above 2000 K. Raman spectroscopy measurements indicate a distinct weakening of the intramolecular bond of the nitrogen molecule above 60 GPa, while transmission measurements in the visible and mid-infrared regime suggest the metallisation of the compound at ~100 GPa. PMID:27748357

  20. Delayed onset muscle soreness: is massage effective?

    PubMed

    Nelson, Nicole

    2013-10-01

    Despite the widespread occurrence of delayed onset muscle soreness (DOMS), there is little consensus as to the exact cause or which treatments may be most effective at alleviating symptoms. Greater understanding of DOMS can give sports medicine and fitness professionals an opportunity to help prevent or speed recovery of this performance limiting condition. This article will review the DOMS literature, including the potential role of psychosocial factors and explore studies which involve massage therapy as a treatment modality. Articles from PubMed, MEDLINE, Google Scholar, and references from articles are included in this review. Search words and phrases included delayed onset muscle soreness, repeated bout effect, massage effectiveness, exercise induced muscle damage, and eccentric exercise.

  1. Managing Sore Throat: Theory Versus Practice

    PubMed Central

    Wong, Thomas; Tiessen, Esther

    1989-01-01

    The authors address the reliability of clinical impression in the management of sore throat. Five primary care family physicians in rural Ontario examined 222 patients with sore throats. The clinical impression of either Group A β-hemolytic streptococcal (GABHS) or non-GABHS pharyngitis was recorded and throat cultures were ordered in each case. The physicians predicted that 50% of the cultures would be positive for GABHS, whereas only 13.5% actually had positive results. The initial clinical diagnosis of “strep throat” was correct only one in five times. Without cultures, at least 112 patients would have been treated with antibiotics, 87 unnecessarily. The authors conclude that the clinical prediction of GABHS is inaccurate and can lead to unnecessary use of antibiotics. PMID:21249054

  2. Delayed onset muscle soreness: mechanisms and management.

    PubMed

    Cleak, M J; Eston, R G

    1992-08-01

    This review describes the phenomenon of delayed onset muscle soreness (DOMS), concentrating upon the types of muscle contraction most likely to produce DOMS and the theories underlying the physiological mechanisms of DOMS. Ways of attempting to reduce the effects of DOMS are also summarized, including the application of physical and pharmacological therapies to reduce the effects of DOMS and training for reduction or prevention of DOMS.

  3. Nimbus 3 alternating-pressure replacement mattress.

    PubMed

    Young, T

    Alternating-pressure surfaces have been shown to reduce the incidence of pressure sores compared with standard hospital mattresses and pressure-reducing (constant low-pressure) surfaces. Huntleigh Healthcare has recently introduced the Nimbus 3 to its range of alternating-pressure mattress replacement systems. This product has been developed according to new medical device regulations and is indicated for the treatment of patients with all grades of pressure sores and for prevention in patients who are at very high risk of developing pressure sores.

  4. HEADCO: a program for converting observed water levels and pressure measurements to formation pressure and standard hydraulic head

    SciTech Connect

    Spane, F.A. Jr.; Mercer, R.B.

    1985-10-01

    Static water-level and fluid pressure measurements are commonly converted in hydrologic studies to formation pressure and hydraulic head, which are used to determine groundwater flow characteristics of aquifer systems. While the direct use of field measurements is usually adequate for determining formation pressure and hydraulic head for shallow flow systems (i.e., <1000 ft), corrections and conversion parameters must be used to properly account for fluid-column density effects, which commonly occur with deep systems. This report presents a program, HEADCO, for converting static water-level and pressure measurements to formation pressure and standard hydraulic head. The HEADCO program corrects field measurements for the effects of fluid-density variation and selected external stresses. Factors that affect density of the fluid column, in which field measurements are made, include temperature, pressure, salinity, suspended solids, and multiphase conditions. External stresses examined in HEADCO include barometric and earth tide fluctuations, and gravitational acceleration variation. A program description and procedures for converting field measurements obtained using field test arrangements commonly employed in the Basalt Waste Isolation Project field program are provided in this report. The report includes user instructions and an illustrative test example. Results of a field example comparison are also provided. This comparison examines observed and HEADCO-calculated pressures for 30 pressure probes recently calibrated in a laboratory and tested under field conditions at borehole DC-8. The test case and field example comparisons indicate that HEADCO provides accurate estimates of formation pressure and standard hydraulic head that are well within the accuracy range of downhole pressure-measuring instrumentation. 44 refs., 14 figs., 8 tabs.

  5. A pressure-induced, magnetic transition in pyrrhotite: Implications for the formation pressure of meteorites and diamonds

    NASA Astrophysics Data System (ADS)

    Gilder, S. A.; Egli, R.; Hochleitner, R.; Roud, S. C.; Volk, M. W. R.; Le Goff, M.; de Wit, M.

    2012-04-01

    Meteorites and diamonds encounter high pressures during their formation or subsequent evolution. These materials sometimes contain magnetic inclusions of pyrrhotite. Because magnetic properties are sensitive to strain, pyrrhotite can potentially record the shock or formation pressures of its host. Moreover, pyrrhotite undergoes a pressure-induced phase transition between 1.6 and 6.2 GPa, but the magnetic signature of this transition is poorly known. Here we report room temperature magnetic measurements on multi- and single domain pyrrhotite under non-hydrostatic pressure up to 4.5 GPa. We find that the ratio of magnetic coercivity and remanence follows a logarithmic law with respect to pressure, which can potentially be used as a geobarometer. Due to the greater thermal expansion of pyrrhotite with respect to diamond, pyrrhotite inclusions in diamond experience a confining pressure at the Earth's surface. Applying our experimentally derived magnetic geobarometer to pyrrhotite-bearing diamonds from Botswana and the Central African Republic suggests the pressures of the pyrrhotite inclusions in the diamonds range from 1.3 to 2.1 GPa. These overpressures constrain the mantle source pressures from 5.4 to 9.5 GPa, depending on which bulk modulus and thermal expansion coefficients of the two phases are used. We are now trying to develop magnetic barometers on other magnetic phases to apply to meteorites, ultimately to constrain the minimum pressure in which the meteorite formed and, hence, information regarding the planetesmal's size, and/or depth, in which the meteorite was derived.

  6. Fuel Structure and Pressure Effects on the Formation of Soot Particles in Diffusion Flames

    DTIC Science & Technology

    1990-05-01

    higher values of the pressure power dependence appear to be related to fuel structure effects , the direct nature of which remains to be understood...61102F 2308 A2 11. TITLE (Include Security Classification) "Fuel Structure and Pressure Effects on the Formation of Soot Particlesin Diffusion Flames...block number) Studies emphasizing the effects of fuel concentration and operating pressure on the formation of soot particles have been conducted in a

  7. The effects of ice massage on delayed muscle soreness.

    PubMed

    Yackzan, L; Adams, C; Francis, K T

    1984-01-01

    The following hypotheses were tested in the present study: (1) cryotherapy would reduce delayed muscle soreness (DMS) in eccentrically exercised muscles; (2) early cold treatment would reduce this soreness more than later postexercise treatment times; and (3) joint range of motion (ROM) would be inversely related to the subjective soreness ratings. Subjective sensations of muscular soreness and changes in elbow joint ROM were assessed in 30 subjects at 0, 24, 48, and 72 hours following eccentric-biased exercise in the elbow flexors. Cold treatments were applied immediately, 24 or 48 hours following a single exercise session. In response to the eccentric exercise, significant muscle soreness increases and elbow ROM decreases were observed in all exercised muscles from 24 to 48 hours postexercise. No differences in muscle soreness or elbow ROM changes were observed between treated and untreated arms except for one. Subjects treated at 24 hours postexercise reported greater soreness in their arms compared to untreated arms just prior to treatment (24 hour postexercise). The results do not support the efficacy of cold in reducing DMS. A negative correlation between muscle soreness and elbow ROM at 48 and 72 hours postexercise indicated that an increase in soreness was associated with a decrease in ROM.

  8. Theoretical assessment of bonaccordite formation in pressurized water reactors

    DOE PAGES

    Rak, Zsolt; O'Brien, Chris; Shin, Dongwon; ...

    2016-03-04

    The free energy of formation of bonaccordite (Ni2FeBO5) as a function of temperature has been calculated using a technique that combines first principles calculations with experimental free energies of formation of aqueous species. The results suggest that bonaccordite formation from aqueous metal ions (Ni2+ andFe3+) and boric acid is thermodynamically favorable at elevated temperature and pH that have been predicted to exist at the CRUD-clad interface in deposits thicker than 60 μm.

  9. Theoretical assessment of bonaccordite formation in pressurized water reactors

    SciTech Connect

    Rak, Zsolt; O'Brien, Chris; Shin, Dongwon; Andersson, Anders David; Stanek, Christopher; Brenner, Donald

    2016-03-04

    The free energy of formation of bonaccordite (Ni2FeBO5) as a function of temperature has been calculated using a technique that combines first principles calculations with experimental free energies of formation of aqueous species. The results suggest that bonaccordite formation from aqueous metal ions (Ni2+ andFe3+) and boric acid is thermodynamically favorable at elevated temperature and pH that have been predicted to exist at the CRUD-clad interface in deposits thicker than 60 μm.

  10. Theoretical assessment of bonaccordite formation in pressurized water reactors

    NASA Astrophysics Data System (ADS)

    Rak, Zs; O'Brien, C. J.; Shin, D.; Andersson, A. D.; Stanek, C. R.; Brenner, D. W.

    2016-06-01

    The free energy of formation of bonaccordite (Ni2FeBO5) as a function of temperature has been calculated using a technique that combines first principles calculations with experimental free energies of formation of aqueous species. The results suggest that bonaccordite formation from aqueous metal ions (Ni2+ andFe3+) and boric acid is thermodynamically favorable at elevated temperature and pH that have been predicted to exist at the CRUD-clad interface in deposits thicker than 60 μm.

  11. Carbon Onions as Nanoscopic Pressure Cells for Diamond Formation

    NASA Astrophysics Data System (ADS)

    Banhart, Florian

    1997-03-01

    Concentric-shell carbon onions form under electron irradiation of different carbon precursors in an electron microscope. Carbon onions under irradiation at high temperature are in a state of high compression with a considerable decrease of the c-plane spacing towards the centre. Under prolonged irradiation at temperatures around 900 K the cores of the graphitic onions transform into diamond crystals (F. Banhart and P.M. Ajayan, Nature 382), 433 (1996). Hence, carbon onions can be thought of as nanoscopic pressure cells for the directly observable nucleation and growth of diamond from graphitic material. The diamond crystals grow under further irradiation until the whole graphitic particles have transformed to diamond. Apparently the conversion of the graphitic structure to diamond starts at high pressure and proceeds at decreasing, possibly even at zero pressure. The experiment is carried out in a transmission electron microscope which enables us to monitor this phase transformation in-situ on an atomic scale.

  12. Pressure-driven formation and stabilization of superconductive chromium hydrides

    NASA Astrophysics Data System (ADS)

    Yu, Shuyin; Jia, Xiaojing; Frapper, Gilles; Li, Duan; Oganov, Artem R.; Zeng, Qingfeng; Zhang, Litong

    2015-12-01

    Chromium hydride is a prototype stoichiometric transition metal hydride. The phase diagram of Cr-H system at high pressures remains largely unexplored due to the challenges in dealing with the high activation barriers and complications in handing hydrogen under pressure. We have performed an extensive structural study on Cr-H system at pressure range 0 ˜ 300 GPa using an unbiased structure prediction method based on evolutionary algorithm. Upon compression, a number of hydrides are predicted to become stable in the excess hydrogen environment and these have compositions of Cr2Hn (n = 2-4, 6, 8, 16). Cr2H3, CrH2 and Cr2H5 structures are versions of the perfect anti-NiAs-type CrH with ordered tetrahedral interstitial sites filled by H atoms. CrH3 and CrH4 exhibit host-guest structural characteristics. In CrH8, H2 units are also identified. Our study unravels that CrH is a superconductor at atmospheric pressure with an estimated transition temperature (T c) of 10.6 K, and superconductivity in CrH3 is enhanced by the metallic hydrogen sublattice with T c of 37.1 K at 81 GPa, very similar to the extensively studied MgB2.

  13. Pressure-driven formation and stabilization of superconductive chromium hydrides

    PubMed Central

    Yu, Shuyin; Jia, Xiaojing; Frapper, Gilles; Li, Duan; Oganov, Artem R.; Zeng, Qingfeng; Zhang, Litong

    2015-01-01

    Chromium hydride is a prototype stoichiometric transition metal hydride. The phase diagram of Cr-H system at high pressures remains largely unexplored due to the challenges in dealing with the high activation barriers and complications in handing hydrogen under pressure. We have performed an extensive structural study on Cr-H system at pressure range 0 ∼ 300 GPa using an unbiased structure prediction method based on evolutionary algorithm. Upon compression, a number of hydrides are predicted to become stable in the excess hydrogen environment and these have compositions of Cr2Hn (n = 2–4, 6, 8, 16). Cr2H3, CrH2 and Cr2H5 structures are versions of the perfect anti-NiAs-type CrH with ordered tetrahedral interstitial sites filled by H atoms. CrH3 and CrH4 exhibit host-guest structural characteristics. In CrH8, H2 units are also identified. Our study unravels that CrH is a superconductor at atmospheric pressure with an estimated transition temperature (T c) of 10.6 K, and superconductivity in CrH3 is enhanced by the metallic hydrogen sublattice with T c of 37.1 K at 81 GPa, very similar to the extensively studied MgB2. PMID:26626579

  14. Anatomy of a pressure-induced, ferromagnetic-to-paramagnetic transition in pyrrhotite: Implications for the formation pressure of diamonds

    NASA Astrophysics Data System (ADS)

    Gilder, Stuart A.; Egli, Ramon; Hochleitner, Rupert; Roud, Sophie C.; Volk, Michael W. R.; Le Goff, Maxime; de Wit, Maarten

    2011-10-01

    Meteorites and diamonds encounter high pressures during their formation or subsequent evolution. These materials commonly contain magnetic inclusions of pyrrhotite. Because magnetic properties are sensitive to strain, pyrrhotite can potentially record the shock or formation pressures of its host. Moreover, pyrrhotite undergoes a pressure-induced phase transition between 1.6 and 6.2 GPa, but the magnetic signature of this transition is poorly known. Here we report room temperature magnetic measurements on multidomain and single-domain pyrrhotite under nonhydrostatic pressure. Magnetic remanence in single-domain pyrrhotite is largely insensitive to pressure until 2 GPa, whereas the remanence of multidomain pyrrhotite increases 50% over that of initial conditions by 2 GPa, and then decreases until only 33% of the original remanence remains by 4.5 GPa. In contrast, magnetic coercivity increases with increasing pressure to 4.5 GPa. Below ˜1.5 GPa, multidomain pyrrhotite obeys Néel theory with a positive correlation between coercivity and remanence; above ˜1.5 GPa, it behaves single domain-like yet distinctly different from uncompressed single-domain pyrrhotite. The ratio of magnetic coercivity and remanence follows a logarithmic law with respect to pressure, which can potentially be used as a geobarometer. Owing to the greater thermal expansion of pyrrhotite with respect to diamond, pyrrhotite inclusions in diamonds experience a confining pressure at Earth's surface. Applying our experimentally derived magnetic geobarometer to pyrrhotite-bearing diamonds from Botswana and the Central African Republic suggests the pressures of the pyrrhotite inclusions in the diamonds range from 1.3 to 2.1 GPa. These overpressures constrain the mantle source pressures from 5.4 to 9.5 GPa, depending on which bulk modulus and thermal expansion coefficients of the two phases are used.

  15. Sore Throat - Multiple Languages: MedlinePlus

    MedlinePlus

    ... gov/languages/sorethroat.html Other topics A-Z A B C D E F G H I J K L M N O P Q R S T U V W XYZ List of All Topics All Sore Throat - Multiple Languages To use the sharing features on this page, please enable JavaScript. Chinese - Traditional (繁體中文) French (français) Hindi (हिन्दी) Japanese (日本語) Korean (한국어) ...

  16. Does Postexercise Static Stretching Alleviate Delayed Muscle Soreness?

    ERIC Educational Resources Information Center

    Buroker, Katherine C.; Schwane, James A.

    1989-01-01

    Because many experts recommend stretching after exercise to relieve muscle soreness, 23 subjects performed a 30-minute step test to induce delayed muscle soreness. There was neither temporary relief of pain immediately after stretching nor a reduction in pain during the 3-day postexercise period. (Author/SM)

  17. Laser homeostatics on delayed onset muscle soreness

    NASA Astrophysics Data System (ADS)

    Liu, T. C. Y.; Fu, D. R.; Liu, X. G.; Tian, Z. X.

    2011-01-01

    Delayed onset muscle soreness (DOMS) and its photobiomodulation were reviewed from the viewpoint of function-specific homeostasis (FSH) in this paper. FSH is a negative-feedback response of a biosystem to maintain the function-specific fluctuations inside the biosystem so that the function is perfectly performed. A stressor may destroy a FSH. A stress is a response of a biosystem to a stressor and may also be in stress-specific homeostasis (StSH). A low level light (LLL) is so defined that it has no effects on a function in its FSH or a stress in its StSH, but it modulate a function far from its FSH or a stress far from its StSH. For DOMS recovery, protein metabolism in the Z-line streaming muscular cell is the essential process, but the inflammation, pain and soreness are non-essential processes. For many DOMS phenomena, protein metabolism in the Z-line streaming muscular cell is in protein metabolism-specific homeostasis (PmSH) so that there are no effects of LLL although the inflammation can be inhibited and the pain can be relieved. An athlete or animal in the dysfunctional conditions such as blood flow restriction and exercise exhaustion is far from PmSH and the protein metabolism can be improved with LLL.

  18. A pressure-induced, magnetic transition in pyrrhotite: Implications for the formation pressure of meteorites and diamonds

    NASA Astrophysics Data System (ADS)

    Gilder, S. A.; Egli, R.; Hochleitner, R.; Roud, S. C.; Volk, M.; Le Goff, M.; de Wit, M.

    2010-12-01

    Meteorites and diamonds encounter high-pressures during their geologic histories. These materials commonly contain magnetic inclusions of pyrrhotite, and because magnetic properties are sensitive to strain, pyrrhotite can potentially record the shock or formation pressures of its host. Moreover, pyrrhotite undergoes a pressure-induced phase transition between 1.6 and 6.2 GPa, but the magnetic signature of this transition is poorly known. Here we report magnetic measurements performed at high-pressures on single and multi-domain pyrrhotite. A magnetic hysteresis model based on our observations suggests that multidomain pyrrhotite transforms into single domain-like material, and once in the single domain state, hysteresis loops become progressively squarer and then squatter with increasing pressure, until they ultimately collapse approaching the paramagnetic state at the transition. The ratio of the bulk magnetic coercive force to magnetic remanence for pure pyrrhotite is reversible with pressure and follows a logarithmic law as a function of pressure, which can be used as a magnetic barometer for natural systems.

  19. Predicted formation of superconducting platinum-hydride crystals under pressure in the presence of molecular hydrogen.

    PubMed

    Kim, Duck Young; Scheicher, Ralph H; Pickard, Chris J; Needs, R J; Ahuja, R

    2011-09-09

    Noble metals adopt close-packed structures at ambient pressure and rarely undergo structural transformation at high pressures. Platinum (Pt) is normally considered to be unreactive and is therefore not expected to form hydrides under pressure. We predict that platinum hydride (PtH) has a lower enthalpy than its constituents solid Pt and molecular hydrogen at pressures above 21.5 GPa. PtH transforms to a hexagonal close-packed or face-centered cubic (fcc) structure between 70 and 80 GPa. Linear response calculations indicate that PtH is a superconductor at these pressures with a critical temperature of about 10-25 K. These findings help to shed light on recent observations of pressure-induced metallization and superconductivity in hydrogen-rich materials. We show that the formation of fcc noble metal hydrides under pressure is common and examine the possibility of superconductivity in these materials.

  20. Formation of an Apokampic Discharge Under Atmospheric Pressure Conditions

    NASA Astrophysics Data System (ADS)

    Skakun, V. S.; Panarin, V. A.; Pechenitsyn, D. S.; Sosnin, É. A.; Tarasenko, V. F.

    2016-09-01

    A new phenomenon is observed in a spark discharge developing under normal conditions in air in a discharge circuit with a capacitive decoupling. It consists in the current channel bending becoming a source of a 4-6 cm long plasma jet directed across the channel. The phenomenon is termed an apokampic discharge or an apokamp. Its emission spectrum contains the bands of electron-vibration transitions from the second positive group of molecular nitrogen. The conditions of formation of an apokamp are experimentally determined. A conclusion is drawn that in order construct a physical model of an apokamp, one has to take into account: 1) the presence of a local gas overheating in the site of the current channel bending, 2) the similarity of the current and voltage time dependences in the corona discharge and in the current channel (becoming a source of an apokamp), and 3) the length of the apokamp plasma jet.

  1. Prediction of subsidence: Relationship between lowering of formation pressure and subsidence due to fluid withdrawal

    SciTech Connect

    Serebryakov, V.A.; Chilingar, G.V.

    2000-06-01

    Abnormally low formation pressures develop in petroleum reservoirs during intensive oil and gas production or in aquifers as a result of water extraction. A simple method is presented for calculating (predicting) the amount of compaction (and resulting subsidence) from the pressure drop in formation due to production, i.e., the increase in the effective pressure p{sub e} (p{sub e} = p{sub t} {minus} p{sub p}, where p{sub t} is the total overburden pressure and p{sub p} is the fluid or pore pressure). This work is based on extensive data collected in Russia. For example, large petroliferous areas in Western Siberia became marshlands as a result of fluid withdrawal. One should remember that sophisticated methods, such as FSMT (direct measurement of rock compaction by wireline tools in situ) and GPS (measurement of surface subsidence by satellite microwave Doppler techniques), are not yet available in many areas of the world.

  2. Blood pressure changes in spontaneously hypertensive rats correlate with aortic prostacyclin formation.

    PubMed Central

    Fahr, A.; Förster, W.; Taube, C.

    1983-01-01

    1 The relationship between the blood pressure fall, induced by antihypertensive drugs or bleeding, and the formation of prostacyclin (PGI2)-like activity in the thoracic aorta of spontaneously hypertensive rats has been investigated. Inhibition of ADP-induced platelet aggregation was used to assess PGI2-like activity. 2 The decreases in blood pressure produced by clonidine, dihydralazine and prazosin were associated with increases of PGI2-like activity of 50-80%. The increase in PGI2-like activity correlated well with the blood pressure decrease, independently of the mechanism of the fall in blood pressure. PMID:6347301

  3. Pregame Sore Throat, Postgame Intensive Care Unit.

    PubMed

    Stork, Natalie C; Smoot, M Kyle

    2016-05-01

    A collegiate football athlete presented, on game day, with an acute onset of sore throat. He was afebrile, speaking in full sentences, without signs of respiratory distress. His examination was negative for lymphadenopathy or tonsillar enlargement or exudate. Twelve hours after initial presentation, he developed acute epiglottitis. He underwent urgent fiberoptic intubation and was empirically treated with broad-spectrum antibiotics and corticosteroids. Currently, there are no published reports of acute epiglottitis in athletes. Consequently, there is no evidence to guide return to play decisions. Return to play, following acute epiglottitis, should include resolution of symptoms and a graded return to play, taking into consideration the level of deconditioning the athlete experienced from hospitalization.

  4. JET FORMATION FROM MASSIVE YOUNG STARS: MAGNETOHYDRODYNAMICS VERSUS RADIATION PRESSURE

    SciTech Connect

    Vaidya, Bhargav; Porth, Oliver; Fendt, Christian; Beuther, Henrik E-mail: fendt@mpia.de

    2011-11-20

    Observations indicate that outflows from massive young stars are more collimated during their early evolution compared to later stages. Our paper investigates various physical processes that impact the outflow dynamics, i.e., its acceleration and collimation. We perform axisymmetric magnetohydrodynamic (MHD) simulations particularly considering the radiation pressure exerted by the star and the disk. We have modified the PLUTO code to include radiative forces in the line-driving approximation. We launch the outflow from the innermost disk region (r < 50 AU) by magnetocentrifugal acceleration. In order to disentangle MHD effects from radiative forces, we start the simulation in pure MHD and later switch on the radiation force. We perform a parameter study considering different stellar masses (thus luminosity), magnetic flux, and line-force strength. For our reference simulation-assuming a 30 M{sub Sun} star-we find substantial de-collimation of 35% due to radiation forces. The opening angle increases from 20 Degree-Sign to 32 Degree-Sign for stellar masses from 20 M{sub Sun} to 60 M{sub Sun }. A small change in the line-force parameter {alpha} from 0.60 to 0.55 changes the opening angle by {approx}8 Degree-Sign . We find that it is mainly the stellar radiation that affects the jet dynamics. Unless the disk extends very close to the star, its force is too small to have much impact. Essentially, our parameter runs with different stellar masses can be understood as a proxy for the time evolution of the star-outflow system. Thus, we have shown that when the stellar mass (thus luminosity) increases with age, the outflows become less collimated.

  5. Time course of muscle soreness following different types of exercise

    PubMed Central

    Vickers, Andrew J

    2001-01-01

    Background Post-exercise muscle soreness is a dull, aching sensation that follows unaccustomed muscular exertion. Primarily on the basis of previous laboratory-based research on eccentric exercise, soreness is usually said to follow an inverted U-shaped curve over time, peaking 24 – 48 hours after exercise. As such, it is often described as "delayed-onset" muscle soreness. In a study of long-distance runners, soreness seemed to peak immediately and then reduce gradually over time. The study is a secondary analysis of clinical trial data that aims to determine whether the time course of soreness following a natural exercise, long-distance running, is different from that following a laboratory-based exercise, bench-stepping. Methods This is a reanalysis of data from three previous clinical trials. The trials included 400 runners taking part in long-distance races and 82 untrained volunteers performing a bench-stepping test. Subjects completed a Likert scale of muscle soreness every morning and evening for the five days following their exercise. Results Interaction between trial and time is highly significant, suggesting a different time course of soreness following running and bench-stepping. 45% of subjects in the bench-stepping trial experienced peak soreness at the third or fourth follow-up (approximately 36 – 48 hours after exercise) compared to only 14% of those in the running trial. The difference between groups is robust to multivariate analysis incorporating possible confounding variables. Conclusion Soreness in runners following long-distance running follows a different time course to that in untrained individuals undertaking bench-stepping. Research on exercise taking place in the laboratory context does not necessarily generalize to exercise undertaken by trained athletes when engaged in their chosen sport. PMID:11701094

  6. A NEW MECHANISM FOR MASS ACCRETION UNDER RADIATION PRESSURE IN MASSIVE STAR FORMATION

    SciTech Connect

    Tanaka, Kei E. I.; Nakamoto, Taishi

    2010-05-01

    During the formation of a massive star, strong radiation pressure from the central star acts on the dust sublimation front and tends to halt the accretion flow. To overcome this strong radiation pressure, it has been considered that a strong ram pressure produced by a high-mass accretion rate of 10{sup -3} M{sub sun} yr{sup -1} or more is needed. We reinvestigated the necessary condition to overcome the radiation pressure and found a new mechanism for overcoming it. Accumulated mass in a stagnant flow near the dust sublimation front helps the mass accretion by its weight. This mechanism relaxes the condition for the massive star formation. We call this mechanism the 'OMOSHI effect', where OMOSHI is an acronym for 'One Mechanism for Overcoming Stellar High radiation pressure by weIght'. Additionally, in Japanese, OMOSHI is a noun meaning a weight that is put on something to prevent it from moving. We investigate the generation of the OMOSHI effect using local one-dimensional radiation hydrodynamics simulations. The radiation pressure and the gravitational force are connected through the gas pressure, and to sum up, the radiation pressure is balanced or overcome by the gravitational force. We also discuss the global structure and temporal variation of the accretion flow.

  7. Can You Get Genital Herpes from a Cold Sore?

    MedlinePlus

    ... Lucy* Yes — it is possible to get genital herpes from oral sex. Genital herpes is caused by the herpes ... Genital herpes is usually caused by HSV-2; oral herpes (cold sores) is usually caused by HSV-1. ...

  8. High pressure rheometer for in situ formation and characterization of methane hydrates

    NASA Astrophysics Data System (ADS)

    Webb, Eric B.; Rensing, Patrick J.; Koh, Carolyn A.; Dendy Sloan, E.; Sum, Amadeu K.; Liberatore, Matthew W.

    2012-01-01

    We present a novel setup for a high pressure rheometer operating with concentric cylinders geometry for in situ studies of hydrate formation and rheological characterization. The apparatus uses an external high pressure mixing cell to saturate water-in-oil emulsions with methane gas. The capability of mixing combined with a true rheometer design make this apparatus unique in terms of setup and sample formation. We have used the apparatus to form gas hydrates in situ from water-in-oil emulsions and characterize suspension rheological properties such as yield stress and shear-thinning behavior.

  9. Guideline for the management of acute sore throat.

    PubMed

    Pelucchi, C; Grigoryan, L; Galeone, C; Esposito, S; Huovinen, P; Little, P; Verheij, T

    2012-04-01

    The European Society for Clinical Microbiology and Infectious Diseases established the Sore Throat Guideline Group to write an updated guideline to diagnose and treat patients with acute sore throat. In diagnosis, Centor clinical scoring system or rapid antigen test can be helpful in targeting antibiotic use. The Centor scoring system can help to identify those patients who have higher likelihood of group A streptococcal infection. In patients with high likelihood of streptococcal infections (e.g. 3-4 Centor criteria) physicians can consider the use of rapid antigen test (RAT). If RAT is performed, throat culture is not necessary after a negative RAT for the diagnosis of group A streptococci. To treat sore throat, either ibuprofen or paracetamol are recommended for relief of acute sore throat symptoms. Zinc gluconate is not recommended to be used in sore throat. There is inconsistent evidence of herbal treatments and acupuncture as treatments for sore throat. Antibiotics should not be used in patients with less severe presentation of sore throat, e.g. 0-2 Centor criteria to relieve symptoms. Modest benefits of antibiotics, which have been observed in patients with 3-4 Centor criteria, have to be weighed against side effects, the effect of antibiotics on microbiota, increased antibacterial resistance, medicalisation and costs. The prevention of suppurative complications is not a specific indication for antibiotic therapy in sore throat. If antibiotics are indicated, penicillin V, twice or three times daily for 10 days is recommended. At the present, there is no evidence enough that indicates shorter treatment length.

  10. Effects of Fish Oil Supplementation on Postresistance Exercise Muscle Soreness.

    PubMed

    Tinsley, Grant M; Gann, Joshua J; Huber, Stefan R; Andre, Thomas L; La Bounty, Paul M; Bowden, Rodney G; Gordon, Paul M; Grandjean, Peter W

    2016-07-21

    The aim of this study was to examine the effects of fish oil supplementation on the magnitude and time-course of postresistance exercise muscle soreness. This study was a randomized, placebo-controlled, double-blind trial. Nonresistance trained females were randomized into one of two groups: fish oil supplementation (6 g/day; 5:1 eicosapentaenoic acid to docosahexaenoic acid (EPA:DHA)) or placebo (6 g/day corn/soy oil). After consuming the supplements for one week, participants underwent a single bout of resistance exercise consisting of 10 sets to failure of elbow flexion and leg extension machines. Muscle soreness was measured daily over the next week via grounded visual analog scale while participants continued to consume their assigned supplement. At 48 hours and one week postexercise, soreness during functional movements and limb circumferences were measured. The fish oil group perceived less static and functional muscle soreness than placebo, although the differences were not statistically significant. Effect sizes for resistance exercise-induced static and functional soreness responses were 33 to 42% lower in fish oil versus placebo without changes in upper arm and thigh circumferences. Supplementing the diet with 6 g per day of fish oil may alleviate muscle soreness experienced after resistance training in young untrained females.

  11. Design and Development of Portable Support Surface and Multilayered Fabric Cover for Bed Sore Prevention.

    PubMed

    Kandha Vadivu, P

    2015-12-01

    Pressure ulcers are serious and common health concern affecting about 1.5-3 million adults and is a serious health concern for elders. Pressure ulcers or bed sores seem to be one of the most challenging inflicts to the doctors and may result in significant morbidity and mortality and are associated with high cost in terms of human sufferings, cost of treatment, and possible litigation. Though modern medical science has launched a variety of treatment methods, prevention is the best way to get rid of it. Pressure sores are best prevented by using support surfaces that are volatile in nature-like water mattress, variable pressure mattress, etc. In this research work, a portable support surface has been designed and developed for preventing bedsore. It consists of four individual components for the body part such as bodice back, hip, elbow, and heel which are likely to be affected by bedsores. Each component has volatile surface provisions in them with refilling and cleaning facility. The portable support surface is easy to wear and remove and also cheaper. Above all, the kit is user-friendly with no side effects and preferred and guaranteed by the doctors.

  12. Tracking CO2 Plume in Deep Saline Formations Utilizing a Time-lapse Pressure Tomography Approach

    NASA Astrophysics Data System (ADS)

    Hu, L.; Bayer, P.; Brauchler, R.

    2015-12-01

    CO2 storage in deep saline formations is considered as an attractive option to cut down greenhouse gas emissions. Among the major challenges is the development of efficient technologies for controlling and monitoring the evolution of CO2 plumes during and after injection in the underground. As an alternative to the most commonly used geophysical approaches for subsurface characterization, we propose a pressure-based tomographical approach to track CO2 plume history. By taking into account the direct relationship between saturation and flow properties, pressure tomography has the potential not only to detect a plume but also to estimate the saturation of CO2. The experimental set-up of pressure tomography involves injection of brine or CO2 at variable depths (sources). We use a time-lapse approach, considering first the CO2-free formation, and then the multi-phase CO2-brine system. By applying a rapid eikonal-based inversion technique, pressure fluctuations at observation locations (receivers) are utilized to reconstruct the spatial distribution of the apparent single-phase and mixed-phase diffusivity. Evolution of the plume shape is then delineated by comparison of diffusivity tomograms derived from different times. Finally, an integrated value of CO2 saturation within the plume is obtained by means of a single-phase proxy. Applicability of this novel approach is evaluated in different virtual formations. The time-lapse pressure tomographic investigation revealed that knowledge about the spatial heterogeneity of permeability has a remarkable impact on proper characterization of plume shape.

  13. Glass formation and cluster evolution in the rapidly solidified monatomic metallic liquid Ta under high pressure

    NASA Astrophysics Data System (ADS)

    Jiang, Dejun; Wen, Dadong; Tian, Zean; Liu, Rangsu

    2016-12-01

    Molecular dynamics (MD) simulations have been performed to examine the glass formation and cluster evolution during the rapid solidification of monatomic metallic liquid Ta under high pressure. The atomic structures in the systems are characterized by the radical distribution function (RDF), Honeycutt-Anderson (H-A) bond-type index method and cluster-type index method (CTIM). It is observed that the defective icosahedra play the critical role in the formation of Ta monatomic metallic glasses (MGs) rather than (12 0 12 0) perfect icosahedra, which have been identified as the basic local atomic units in many multi-component MGs. With the increase of pressure P, the fraction of icosahedral type clusters decreases remarkably in Ta MGs, while the fraction of bcc type clusters rises evidently. The evolution of vitrification degree (DSRO or DMRO) of the rapidly cooled metal Ta system further reveals that a higher pressure P is disadvantageous to the formation of Ta monatomic MGs. The weaker glass forming ability (GFA) of liquid metal Ta obtained under higher pressure P can be contributed to the decrease of DSRO or DMRO which is induced by increasing high pressure P to some extent.

  14. Experimental modeling of pressurized subglacial water flow: Implications for tunnel valley formation

    NASA Astrophysics Data System (ADS)

    Lelandais, Thomas; Mourgues, Régis; Ravier, Édouard; Pochat, Stéphane; Strzerzynski, Pierre; Bourgeois, Olivier

    2016-11-01

    Tunnel valleys are elongated hollows commonly found in formerly glaciated areas and interpreted as resulting from subglacial meltwater erosion beneath ice sheets. Over the past two decades, the number of studies of terrestrial tunnel valleys has continuously increased, and their existence has been hypothesized also on Mars, but their formation mechanisms remain poorly understood. We introduce here an innovative experimental approach to examine erosion by circulation of pressurized meltwater within the substratum and at the ice/substratum interface. We used a permeable substratum (sand) partially covered by a viscous, impermeable, and transparent cap (silicon putty), below which we applied a central injection of pure water. Low water pressures led to groundwater circulation in the substratum only, while water pressures exceeding a threshold that is larger than the sum of the glaciostatic and lithostatic pressures led to additional water circulation and formation of drainage landforms at the cap/substratum interface. The formation of these drainage landforms was monitored through time, and their shapes were analyzed from digital elevation models obtained by stereo-photogrammetry. The experimental landforms include valleys that are similar to natural tunnel valleys in their spatial organization and in a number of diagnostic morphological criteria, such as undulating longitudinal profiles and "tunnel" shapes. These results are consistent with the hypothesis that overpressurized subglacial water circulation controls the formation of tunnel valleys.

  15. Pressure-dependent formation of i-motif and G-quadruplex DNA structures.

    PubMed

    Takahashi, S; Sugimoto, N

    2015-12-14

    Pressure is an important physical stimulus that can influence the fate of cells by causing structural changes in biomolecules such as DNA. We investigated the effect of high pressure on the folding of duplex, DNA i-motif, and G-quadruplex (G4) structures; the non-canonical structures may be modulators of expression of genes involved in cancer progression. The i-motif structure was stabilized by high pressure, whereas the G4 structure was destabilized. The melting temperature of an intramolecular i-motif formed by 5'-dCGG(CCT)10CGG-3' increased from 38.8 °C at atmospheric pressure to 61.5 °C at 400 MPa. This effect was also observed in the presence of 40 wt% ethylene glycol, a crowding agent. In the presence of 40 wt% ethylene glycol, the G4 structure was less destabilized than in the absence of the crowding agent. P-T stability diagrams of duplex DNA with a telomeric sequence indicated that the duplex is more stable than G4 and i-motif structures under low pressure, but the i-motif dominates the structural composition under high pressure. Under crowding conditions, the P-T diagrams indicated that the duplex does not form under high pressure, and i-motif and G4 structures dominate. Our findings imply that temperature regulates the formation of the duplex structure, whereas pressure triggers the formation of non-canonical DNA structures like i-motif and G4. These results suggest that pressure impacts the function of nucleic acids by stabilizing non-canonical structures; this may be relevant to deep sea organisms and during evolution under prebiotic conditions.

  16. Rogue wave formation under the action of quasi-stationary pressure

    NASA Astrophysics Data System (ADS)

    Abrashkin, A. A.; Oshmarina, O. E.

    2016-05-01

    The process of rogue wave formation on deep water is considered. A wave of extreme amplitude is born against the background of uniform waves (Gerstner waves) under the action of external pressure on free surface. The pressure distribution has a form of a quasi-stationary "pit". The fluid motion is supposed to be a vortex one and is described by an exact solution of equations of 2D hydrodynamics for an ideal fluid in Lagrangian coordinates. Liquid particles are moving around circumferences of different radii in the absence of drift flow. Values of amplitude and wave steepness optimal for rogue wave formation are found numerically. The influence of vorticity distribution and pressure drop on parameters of the fluid is investigated.

  17. Effects of hydrogen partial pressure on autotrophic growth and product formation of Acetobacterium woodii.

    PubMed

    Kantzow, Christina; Weuster-Botz, Dirk

    2016-08-01

    Low aqueous solubility of the gases for autotrophic fermentations (e.g., hydrogen gas) results in low productivities in bioreactors. A frequently suggested approach to overcome mass transfer limitation is to increase the solubility of the limiting gas in the reaction medium by increasing the partial pressure in the gas phase. An increased inlet hydrogen partial pressure of up to 2.1 bar (total pressure of 3.5 bar) was applied for the autotrophic conversion of hydrogen and carbon dioxide with Acetobacterium woodii in a batch-operated stirred-tank bioreactor with continuous gas supply. Compared to the autotrophic batch process with an inlet hydrogen partial pressure of 0.4 bar (total pressure of 1.0 bar) the final acetate concentration after 3.1 days was reduced to 50 % (29.2 g L(-1) compared to 59.3 g L(-1)), but the final formate concentration was increased by a factor of 18 (7.3 g L(-1) compared to 0.4 g L(-1)). Applying recombinant A. woodii strains overexpressing either genes for enzymes in the methyl branch of the Wood-Ljungdahl pathway or the genes phosphotransacetylase and acetate kinase at an inlet hydrogen partial pressure of 1.4 bar reduced the final formate concentration by up to 40 % and increased the final dry cell mass and acetate concentrations compared to the wild type strain. Solely the overexpression of the two genes for ATP regeneration at the end of the Wood-Ljungdahl pathway resulted in an initial switch off of formate production at increased hydrogen partial pressure until the maximum of the hydrogen uptake rate was reached.

  18. Nipple care, sore nipples, and breastfeeding: a randomized trial.

    PubMed

    Centuori, S; Burmaz, T; Ronfani, L; Fragiacomo, M; Quintero, S; Pavan, C; Davanzo, R; Cattaneo, A

    1999-06-01

    Sore and cracked nipples are common and may represent an obstacle to successful breastfeeding. In Italy, it is customary for health professionals to prescribe some type of ointment to prevent or treat sore and cracked nipples. The efficacy of these ointments is insufficiently documented. The incidence of sore and cracked nipples was compared between mothers given routine nipple care, including an ointment (control group), and mothers instructed to avoid the use of nipple creams and other products (intervention group). Breastfeeding duration was also compared between the two groups. Eligible mothers were randomly assigned, after informed consent, to one of the two groups. No difference was found between the control (n = 96) and the intervention group (n = 123) in the incidence of sore and cracked nipples and in breastfeeding duration. However, several factors were associated with sore nipples and with breastfeeding duration. The use of a pacifier and of a feeding bottle in the hospital were both associated with sore nipples at discharge (p = 0.02 and p = 0.03, respectively). Full breastfeeding up to 4 months postpartum was significantly associated with the following early practices: breastfeeding on demand, rooming-in at least 20 hours/day, non-use of formula and pacifier, no test-weighing at each breastfeed. The incidence of sore and cracked nipples and the duration of breastfeeding were not influenced by the use of a nipple ointment. Other interventions, such as providing the mother with guidance and support on positioning and latching, and modifications of hospital practices may be more effective in reducing nipple problems.

  19. The effect of caffeine ingestion on delayed onset muscle soreness.

    PubMed

    Hurley, Caitlin F; Hatfield, Disa L; Riebe, Deborah A

    2013-11-01

    The beneficial effects of caffeine on aerobic activity and resistance training performance are well documented. However, less is known concerning caffeine's potential role in reducing perception of pain and soreness during exercise. In addition, there is no information regarding the effects of caffeine on delayed onset muscle soreness (DOMS). The primary purpose of this study was to examine the effect of caffeine ingestion on muscle soreness, blood enzyme activity, and performance after a bout of elbow flexion/extension exercise. Nine low-caffeine-consuming males (body mass: 76.68 ± 8.13 kg; height: 179.18 ± 9.35 cm; age: 20 ± 1 year) were randomly assigned to ingest either caffeine or placebo 1 hour before completing 4 sets of 10 bicep curls on a preacher bench, followed by a fifth set in which subjects completed as many repetitions as possible. Soreness and soreness on palpation intensity were measured using three 0-10 visual analog scales before exercise, and 24, 48, 72, 96, and 120 hours after exercise. After a washout period, subjects crossed over to the other treatment group. Caffeine ingestion resulted in significantly (p ≤ 0.05) lower levels of soreness on day 2 and day 3 compared with placebo. Total repetitions in the final set of exercise increased with caffeine ingestion compared with placebo. This study demonstrates that caffeine ingestion immediately before an upper-body resistance training out enhances performance. A further beneficial effect of sustained caffeine ingestion in the days after the exercise bout is an attenuation of DOMS. This decreased perception of soreness in the days after a strenuous resistance training workout may allow individuals to increase the number of training sessions in a given time period.

  20. Silicon nitride-aluminum oxide solid solution (SiAION) formation and densification by pressure sintering

    NASA Technical Reports Server (NTRS)

    Yeh, H. C.; Sanders, W. A.; Fiyalko, J. L.

    1975-01-01

    Stirred-ball-mill-blended Si3N4 and Al2O3 powders were pressure sintered in order to investigate the mechanism of solid solution formation and densification in the Si3N4-Al2O3 system. Powder blends with Si3N4:Al2O3 mole ratios of 4:1, 3:2, and 2:3 were pressure sintered at 27.6-MN/sq m pressure at temperatures to 17000 C (3090 F). The compaction behavior of the powder blends during pressure sintering was determined by observing the density of the powder compact as a function of temperature and time starting from room temperature. This information, combined with the results of X-ray diffraction and metallographic analyses regarding solutioning and phase transformation phenomena in the Si3N4-Al2O3 system, was used to describe the densification behavior.

  1. Formation mechanisms of rapid pressure recovery around a laminar separation bubble

    NASA Astrophysics Data System (ADS)

    Lee, Donghwi; Nonomura, Taku; Oyama, Akira; Fujii, Kozo

    2016-11-01

    Large-eddy simulations around 5 % thickness flat plate are conducted at Rec = 5 , 000 , 8 , 000 and 20 , 000 and formation mechanisms of rapid pressure recovery in the surface pressure distribution around laminar separation bubbles are analyzed. Three analyses are applied to investigate the mechanisms of rapid pressure recovery. First, by using the Reynolds averaged streamwise pressure gradient equation, it is confirmed that the "overall Reynolds stress diffusion (ORSD)" is an important factor for inducing rapid pressure recovery. Second, we decompose the ORSD into the "normal Reynolds stress diffusion in the streamwise direction" and the "tangential Reynolds stress diffusion (TRSD) in the wall-normal direction". We show that the TRSD in the wall-normal direction, which corresponds to the momentum transfer in the same direction, is the main contributor to the ORSD. Third, the TRSD in the wall-normal direction is decomposed into two- and three-dimensional components. The results indicate that the rapid pressure recovery is strongly affected by the presence of Reynolds stress rather than by the type of physical phenomena that creates the Reynolds stress. In other words, the three-dimensional turbulent structures are not a necessary condition for the rapid pressure recovery. Grain-in-Aid for JSPS Fellows.

  2. Does Pressure Accentuate General Relativistic Gravitational Collapse and Formation of Trapped Surfaces?

    NASA Astrophysics Data System (ADS)

    Mitra, Abhas

    2013-04-01

    It is widely believed that though pressure resists gravitational collapse in Newtonian gravity, it aids the same in general relativity (GR) so that GR collapse should eventually be similar to the monotonous free fall case. But we show that, even in the context of radiationless adiabatic collapse of a perfect fluid, pressure tends to resist GR collapse in a manner which is more pronounced than the corresponding Newtonian case and formation of trapped surfaces is inhibited. In fact there are many works which show such collapse to rebound or become oscillatory implying a tug of war between attractive gravity and repulsive pressure gradient. Furthermore, for an imperfect fluid, the resistive effect of pressure could be significant due to likely dramatic increase of tangential pressure beyond the "photon sphere." Indeed, with inclusion of tangential pressure, in principle, there can be static objects with surface gravitational redshift z → ∞. Therefore, pressure can certainly oppose gravitational contraction in GR in a significant manner in contradiction to the idea of Roger Penrose that GR continued collapse must be unstoppable.

  3. Formation of chemical bonds and morphological studies of a-CNx : Effects of PECVD deposition pressure

    NASA Astrophysics Data System (ADS)

    Purhanudin, Noorain; Awang, Rozidawati

    2016-11-01

    We report the structural difference and film properties of amorphous carbon nitride (a-CNx) thin films as a function of PECVD deposition pressure using precursor gases of ethane (C2H6) and nitrogen (N2). The Fourier transform infra-red (FTIR) spectra reveal peaks of single C-N (1100 cm-1), double C=C (1500 cm-1), double C=N (1670 cm-1) and triple C≡N (2340 cm-1). A systematic change in the preferential peaks correspond to the C=N and C≡N triple bonds were found to increase as deposition pressure increased. Field emission scanning electron microscopy (FESEM) provides morphological structure of the film. From the samples prepare at low deposition pressure, the particles tend to agglomerate into clusters with non-homogenous grains distributed over the surface. Higher deposition pressure results in coalescence process of the film, reflecting the formation of grains evenly distributed on the film. The film morphology is increased in voids structure with increase in deposition pressure. Finally, the samples were successfully prepared by PECVD technique with deposition pressure in varied, and the effect of deposition pressure on the chemical bonding and the morphology of the films had been studied.

  4. Pressure Propagation and Brine Displacement in CO2 Storage Formations: The Role of Sealing Units

    NASA Astrophysics Data System (ADS)

    Tsang, C.; Birkholzer, J. T.; Zhou, Q.

    2007-12-01

    If carbon dioxide capture and storage technologies are implemented on a large scale, enormous amounts of CO2 will be injected and sequestered underground, which means that large volumes of native brines will be displaced. Provided that there is hydraulic communication to shallow formations, such brine displacement from deep storage reservoirs may impact the hydrologic conditions in fresh-water aquifers, for example affecting groundwater table levels or discharge and recharge zones. In some cases, brines or brackish water may also be displaced into the capture zone of fresh-water wells. To explore the conditions important for pressure propagation and brine displacement, we conduct a simulation study investigating the multiphase processes resulting from CO2 injection into a large multi-layer geologic system comprising of a storage formation and the confining low- permeability sealing units. The pressure changes and transport patterns within the storage formation are evaluated as a function of time and distance from the injection point. We are particularly interested in the role of pressure mitigation and vertical brine flow through the upper and lower sealing units. Several sensitivity cases are therefore considered varying the permeability of the upper and lower sealing units within reasonable ranges. Our results suggest that seal conductivities on the order of 0.1 to 0.001 millidarcy may allow for considerable pressure attenuation in the storage formation by interlayer brine migration, while still providing an effective barrier to CO2 leakage (since they serve as capillary and permeability seals). It is thus important to fully understand the multi-layer characteristics of a storage site if the possible environmental impacts of CO2 injection on fresh-water aquifers are to be investigated. In addition to conducting detailed simulations of the multi-phase processes, we also investigate whether existing analytical solutions for well drawdown in leaky aquifers can

  5. TURBULENCE SETS THE INITIAL CONDITIONS FOR STAR FORMATION IN HIGH-PRESSURE ENVIRONMENTS

    SciTech Connect

    Rathborne, J. M.; Contreras, Y.; Longmore, S. N.; Bastian, N.; Jackson, J. M.; Kruijssen, J. M. D.; Alves, J. F.; Bally, J.; Foster, J. B.; Garay, G.; Testi, L.; Walsh, A. J.

    2014-11-10

    Despite the simplicity of theoretical models of supersonically turbulent, isothermal media, their predictions successfully match the observed gas structure and star formation activity within low-pressure (P/k < 10{sup 5} K cm{sup –3}) molecular clouds in the solar neighborhood. However, it is unknown whether or not these theories extend to clouds in high-pressure (P/k > 10{sup 7} K cm{sup –3}) environments, like those in the Galaxy's inner 200 pc central molecular zone (CMZ) and in the early universe. Here, we present Atacama Large Millimeter/submillimeter Array 3 mm dust continuum emission within a cloud, G0.253+0.016, which is immersed in the high-pressure environment of the CMZ. While the log-normal shape and dispersion of its column density probability distribution function (PDF) are strikingly similar to those of solar neighborhood clouds, there is one important quantitative difference: its mean column density is one to two orders of magnitude higher. Both the similarity and difference in the PDF compared to those derived from solar neighborhood clouds match predictions of turbulent cloud models given the high-pressure environment of the CMZ. The PDF shows a small deviation from log-normal at high column densities confirming the youth of G0.253+0.016. Its lack of star formation is consistent with the theoretically predicted, environmentally dependent volume density threshold for star formation which is orders of magnitude higher than that derived for solar neighborhood clouds. Our results provide the first empirical evidence that the current theoretical understanding of molecular cloud structure derived from the solar neighborhood also holds in high-pressure environments. We therefore suggest that these theories may be applicable to understand star formation in the early universe.

  6. The effects of massage on delayed onset muscle soreness

    PubMed Central

    Hilbert, J; Sforzo, G; Swensen, T

    2003-01-01

    Objectives: The purpose of this study was to investigate the physiological and psychological effects of massage on delayed onset muscle soreness (DOMS). Methods: Eighteen volunteers were randomly assigned to either a massage or control group. DOMS was induced with six sets of eight maximal eccentric contractions of the right hamstring, which were followed 2 h later by 20 min of massage or sham massage (control). Peak torque and mood were assessed at 2, 6, 24, and 48 h postexercise. Range of motion (ROM) and intensity and unpleasantness of soreness were assessed at 6, 24, and 48 h postexercise. Neutrophil count was assessed at 6 and 24 h postexercise. Results: A two factor ANOVA (treatment v time) with repeated measures on the second factor showed no significant treatment differences for peak torque, ROM, neutrophils, unpleasantness of soreness, and mood (p > 0.05). The intensity of soreness, however, was significantly lower in the massage group relative to the control group at 48 h postexercise (p < 0.05). Conclusions: Massage administered 2 h after exercise induced muscle injury did not improve hamstring function but did reduce the intensity of soreness 48 h after muscle insult. PMID:12547748

  7. Pressure-temperature evolution of Neoproterozoic metamorphism in the Welayati Formation (Kabul Block), Afghanistan

    NASA Astrophysics Data System (ADS)

    Collett, Stephen; Faryad, Shah Wali

    2015-11-01

    The Welayati Formation, consisting of alternating layers of mica-schist and quartzite with lenses of amphibolite, unconformably overlies the Neoarchean Sherdarwaza Formation of the Kabul Block that underwent Paleoproterozoic granulite-facies and Neoproterozoic amphibolite-facies metamorphic events. To analyze metamorphic history of the Welayati Formation and its relations to the underlying Sherdarwaza Formation, petrographic study and pressure-temperature (P-T) pseudosection modeling were applied to staurolite- and kyanite-bearing mica-schists, which crop out to the south of Kabul City. Prograde metamorphism, identified by inclusion trails and chemical zonation in garnet from the micaschists indicates that the rocks underwent burial from around 6.2 kbar at 525 °C to maximum pressure conditions of around 9.5 kbar at temperatures of around 650 °C. Decompression from peak pressures under isothermal or moderate heating conditions are indicated by formation of biotite and plagioclase porphyroblasts which cross-cut and overgrow the dominant foliation. The lack of sillimanite and/or andalusite suggests that cooling and further decompression occurred in the kyanite stability field. The results of this study indicate a single amphibolite-facies metamorphism that based on P-T conditions and age dating correlates well with the Neoproterozoic metamorphism in the underlying Sherdarwaza Formation. The rocks lack any paragenetic evidence for a preceding granulite-facies overprint or subsequent Paleozoic metamorphism. Owing to the position of the Kabul Block, within the India-Eurasia collision zone, partial replacement of the amphibolite-facies minerals in the micaschist could, in addition to retrogression of the Neoproterozoic metamorphism, relate to deformation associated with the Alpine orogeny.

  8. The formation of chondrules at high gas pressures in the solar nebula.

    PubMed

    Galy, A; Young, E D; Ash, R D; O'Nions, R K

    2000-12-01

    High-precision magnesium isotope measurements of whole chondrules from the Allende carbonaceous chondrite meteorite show that some aluminum-rich Allende chondrules formed at or near the time of formation of calcium-aluminum-rich inclusions and that some others formed later and incorporated precursors previously enriched in magnesium-26. Chondrule magnesium-25/magnesium-24 correlates with [magnesium]/[aluminum] and size, the aluminum-rich, smaller chondrules being the most enriched in the heavy isotopes of magnesium. These relations imply that high gas pressures prevailed during chondrule formation in the solar nebula.

  9. Formation processes of nanometer sized particles in low pressure Ar/CH{sub 4} rf plasmas

    SciTech Connect

    Beckers, J.; Vacaresse, G. D. G. J.; Stoffels, W. W.

    2008-09-07

    In this paper, formation and growth processes of nanometer and micrometer sized dust particles in low pressure Ar/CH{sub 4} rf (13.56 MHz) plasmas are investigated as function of temperature in the range 25-100 deg. C. During experiments the pressure was typically 0.8 mbar and the forward power to the plasma was {approx}70 Watt. Measuring the fundamental voltage, current and phase angle together with their harmonics (up to the fourth) gives a good method to monitor the creation and growth of these dust particles in time. Furthermore, laser light scattering measurements are performed to give information about the dust particle density. It has been shown that dust particle formation in these conditions depends greatly on temperature.

  10. Pressure dependence of the compressibility of a micelle and a protein: insights from cavity formation analysis

    NASA Astrophysics Data System (ADS)

    Pereira, Brian; Jain, Sandeep; Sarupria, Sapna; Yang, Lu; Garde, Shekhar

    We present results from molecular dynamics simulations of a spherical micelle comprising 80 non-ionic C8E5 surfactants in water, a protein staphylococcal nuclease in water, and bulk n-hexane and water liquids over a range of hydrostatic pressures. We focus specifically on the pressure dependence of the volumetric properties - the partial molar volume and partial molar compressibility - of the micelle, the protein, and bulk liquids. We find that the micelle interior displays properties similar to liquid alkanes over a range of pressures and has a compressibility of ˜100-110×10-6 bar-1 under ambient conditions, which is more than twice that of liquid water. In contrast, the pressure dependence of the protein interior resembles that of solid organic polymeric materials and has a compressibility of ˜ 5-10×10-6 bar-1. We performed extensive analysis of cavity formation in all systems. Interestingly, it is not the average cavity size but the width of the cavity size distribution in a given medium that correlates with the compressibility of that medium over a broad range of pressures up to several kilobars. Correspondingly, the cavity size distribution is most sharply defined in protein interiors and is broadest in the micelle interior and in n-hexane. To explore the correlation between cavity formation and compressibility, we present preliminary calculations using the information theory approach in the bulk water phase. Analysis of cavity formation and, especially, the nature of the cavity size distribution may provide a sensitive probe of the compressibility and flexibility of local molecular environments in inhomogeneous condensed media.

  11. Prediction of Fracture Initiation Pressure and Fracture Geometries in Elastic Isotropic and Anisotropic Formations

    NASA Astrophysics Data System (ADS)

    Li, H.; Zou, Y. S.; Liu, S.; Liu, G. Q.; Jing, Y. Z.; Ehlig-Economides, C. A.

    2017-03-01

    Laminated formation structures in shale formations may have elastic anisotropic properties, including Young's modulus and Poisson's ratio, that impact hydraulic fracturing treatment execution. Fracture initiation pressures and geometries are affected by these properties, especially in cased and in perforated horizontal wells. After initiation, stress concentration around the wellbore may cause the creation of longitudinal fractures (LFs) in the near-wellbore zone that reorient to transverse fractures (TFs) beyond this region. In this case, severe fracture kinking may occur that may hinder the transport of proppants and reduce well productivity. We developed an analytical model based on linear fracture mechanics theory to study the effect of perforation geometries on the initiation fracture pattern. Elastic anisotropy and well deviations were incorporated into simulations. Our simulation results show that when the perforation depth is in a specific range under normal fault regime, the initiation pressures for LFs can be smaller than the maximum horizontal stress σH. This behavior is significant for a smaller σH /σv ratio, but it vanishes for a larger σH /σv ratio. With increasing formation elastic anisotropy (K_{aniso}), the initiation pressures for both LFs and TFs increase, and the critical perforation depth is decreased. Considering the well deviation, the well azimuth and inclination angles affect initiation pressures for both longitudinal and transverse fractures. Results show how perforation depth, shale elastic anisotropy, and well orientation affect fracture initiation patterns. This paper provides a framework for well completion designs and well orientation designs to minimize the fracture kinking in the near-wellbore region in shale formations.

  12. Delayed onset muscle soreness and perceived exertion following blood flow restriction exercise.

    PubMed

    Brandner, Christopher R; Warmington, Stuart A

    2017-01-11

    The purpose of this study was to determine the perceptual responses to resistance exercise with either heavy-loads (80% 1 repetition maximum [1-RM]), light-loads (20% 1-RM), or light-loads in combination with blood flow restriction (BFR). Despite the use of light-loads, it has been suggested that the adoption of BFR resistance exercise may be limited due to increases in delayed onset muscle soreness (DOMS) and perceived exertion. Seventeen healthy untrained males participated in this balanced, randomized cross-over study. Following four sets of elbow-flexion exercise, participants reported ratings of perceived exertion (RPE), with DOMS also recorded for seven days following each trial. DOMS was significantly greater for low-pressure continuous BFR (until 48 h post-exercise) and high-pressure intermittent BFR (until 72 h post-exercise) compared with traditional heavy-load and light-load resistance exercise. In addition, RPE was higher for heavy-load resistance exercise and high-pressure intermittent BFR compared with low-pressure continuous BFR, with all trials greater than light-load resistance exercise. For practitioners working with untrained participants, this study provides evidence to suggest that in order to minimize the perception of effort and post-exercise muscle soreness associated with BFR resistance exercise, continuous low-pressure application may be more preferential compared with intermittent high-pressure application. Importantly, these perceptual responses are relatively short-lived (∼2 days) and have previously been shown to subside after a few exercise sessions. Combined with smaller initial training volumes (set x repetitions) this may limit RPE and DOMS to strengthen uptake and adherence, and assist in program progression for muscle hypertrophy and gains in strength.

  13. Polymorphism and Formation Mechanism of Nanobipods in Manganese Sulfide Nanocrystals Induced by Temperature or Pressure

    SciTech Connect

    Yang, Xinyi; Wang, Yingnan; Wang, Kai; Sui, Yongming; Zhang, Meiguang; Li, Bing; Ma, Yanming; Liu, Bingbing; Zou, Guangtian; Zou, Bo

    2012-03-15

    Manganese sulfide (MnS) nanocrystals (NCs) with three different phases were synthesized by one-pot solvent thermal approach. The crystal structures and morphologies were investigated using powder X-ray diffraction, transmission electron microscopy, and high-resolution transmission electron microscopy. We found that the crystal structure and morphology of MnS NCs could be controlled by simply varying the reaction temperature. The detailed growth process of MnS nanobipods, including the zinc blende (ZB)-core formation and wurtzite (WZ)-arms growth, provides direct experimental evidence for the polymorphism model. Furthermore, we have studied the stability of metastable ZB- and WZ-MnS NCs under high pressure and found that ZB-nanoparticles and ZB/WZ-nanobipods are stable below their critical pressure, 5.3 and 2.9 GPa, respectively. When pressures exceed the critical point, all these metastable MnS NCs directly convert to the stable rock salt MnS.

  14. Effect of Saturation Pressure Difference on Metal–Silicide Nanopowder Formation in Thermal Plasma Fabrication

    PubMed Central

    Shigeta, Masaya; Watanabe, Takayuki

    2016-01-01

    A computational investigation using a unique model and a solution algorithm was conducted, changing only the saturation pressure of one material artificially during nanopowder formation in thermal plasma fabrication, to highlight the effects of the saturation pressure difference between a metal and silicon. The model can not only express any profile of particle size–composition distribution for a metal–silicide nanopowder even with widely ranging sizes from sub-nanometers to a few hundred nanometers, but it can also simulate the entire growth process involving binary homogeneous nucleation, binary heterogeneous co-condensation, and coagulation among nanoparticles with different compositions. Greater differences in saturation pressures cause a greater time lag for co-condensation of two material vapors during the collective growth of the metal–silicide nanopowder. The greater time lag for co-condensation results in a wider range of composition of the mature nanopowder.

  15. Explicit modelling of SOA formation from α-pinene photooxidation: sensitivity to vapour pressure estimation

    NASA Astrophysics Data System (ADS)

    Valorso, R.; Aumont, B.; Camredon, M.; Raventos-Duran, T.; Mouchel-Vallon, C.; Ng, N. L.; Seinfeld, J. H.; Lee-Taylor, J.; Madronich, S.

    2011-07-01

    The sensitivity of the formation of secondary organic aerosol (SOA) to the estimated vapour pressures of the condensable oxidation products is explored. A highly detailed reaction scheme was generated for α-pinene photooxidation using the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A). Vapour pressures (Pvap) were estimated with three commonly used structure activity relationships. The values of Pvap were compared for the set of secondary species generated by GECKO-A to describe α-pinene oxidation. Discrepancies in the predicted vapour pressures were found to increase with the number of functional groups borne by the species. For semi-volatile organic compounds (i.e. organic species of interest for SOA formation), differences in the predicted Pvap range between a factor of 5 to 200 on average. The simulated SOA concentrations were compared to SOA observations in the Caltech chamber during three experiments performed under a range of NOx conditions. While the model captures the qualitative features of SOA formation for the chamber experiments, SOA concentrations are systematically overestimated. For the conditions simulated, the modelled SOA speciation appears to be rather insensitive to the Pvap estimation method.

  16. Explicit modelling of SOA formation from α-pinene photooxidation: sensitivity to vapour pressure estimation

    NASA Astrophysics Data System (ADS)

    Valorso, R.; Aumont, B.; Camredon, M.; Raventos-Duran, T.; Mouchel-Vallon, C.; Ng, N. L.; Seinfeld, J. H.; Lee-Taylor, J.; Madronich, S.

    2011-03-01

    The sensitivity of the formation of secondary organic aerosol (SOA) to the estimated vapour pressures of the condensable oxidation products is explored. A highly detailed reaction scheme was generated for α-pinene photooxidation using the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A). Vapour pressures (Pvap) were estimated with three commonly used structure activity relationships. The values of Pvap were compared for the set of secondary species generated by GECKO-A to describe α-pinene oxidation. Discrepancies in the predicted vapour pressures were found to increase with the number of functional groups borne by the species. For semi-volatile organic compounds (i.e. organic species of interest for SOA formation), differences in the predicted Pvap range between a factor of 5 to 200 in average. The simulated SOA concentrations were compared to SOA observations in the Caltech chamber during three experiments performed under a range of NOx conditions. While the model captures the qualitative features of SOA formation for the chamber experiments, SOA concentrations are systematically overestimated. For the conditions simulated, the modelled SOA speciation appears to be rather insensitive to the Pvap estimation method.

  17. Post-Intubation Sore Throat and Menstruation Cycles

    PubMed Central

    Orandi, Amirali; Orandi, Amirhossein; Najafi, Atabak; Hajimohammadi, Fatemeh; Soleimani, Sara; Zahabi, Somayeh

    2013-01-01

    Background Postoperative sore throat is one of the most common complications of general anesthesia and intubation with prevalence of 18%-65% in different studies. Several risk factors including female gender, postoperative nausea and vomiting and so on have been mentioned. Objectives The aim of this study was to evaluate the incidence of postoperative sore throat in females and its association with menstrual cycles. Patients and Methods One hundred females between 18-45 years old with ASA class I or II without predicted difficult airway that were candidate for operation in supine position were enrolled in study. Patients who had pulmonary disease, smoking, common cold within two weeks prior to the operation, previous traumatic intubation history, removable dentures, any congenital or acquired deformity in face, neck, mouth and airway, any known pathology in mouth like aphthous and mouth ulcer,pregnant women, and patients with irregular cycles, and those taking oral contraceptive pills were excluded. By the same protocol general anesthesia was provided and the patients were asked to fill out a three-point scale questionnaire (Low, High, None) 1,6 and 24 hours following intubation to study and record the incidence and severity of sore throat, dysphagia and hoarseness. The date of last menstrual period had been recorded as well. Results Of 100 patients, in the first six hours, 51 patients had sore throat and 49 had no pain. During the first 6 hours, 33 patients (33%) had dysphagia and 13 patients had hoarseness at 6th postoperative hour. Age, weight, LMP, intubation time, operation and extubation time and coughing were compared to sore throat, dysphagia and hoarseness. The association between the incidence of coughing and bucking and sore throat was significant (P = 0.03). None of the parameters had a statistically meaningful association with dysphagia. Conclusions According to our results, by omitting probable risk factors of incidence of sore throat and evaluation

  18. Star formation in a high-pressure environment: An SMA view of the dust ridge

    NASA Astrophysics Data System (ADS)

    Walker, Daniel L.

    2017-01-01

    The star formation rate in the Central Molecular Zone is an order of magnitude lower than in the disk of the Galaxy, given the amount of dense gas there. Understanding why star formation is different in this region is crucial if we are to understand the environmental dependence of star formation. Here, we present the detection of high-mass cores in the CMZ's `dust ridge' that have been discovered with the Submillimeter Array. These cores range in mass from ~ 50 - 1800 M⊙ within radii of 0.1 - 0.25 pc. All are young (pre-UCHII), meaning that they are prime candidates for representing the initial conditions of high-mass stars and sub-clusters. We compare these with high-mass cores and clouds in the Galactic disk and find that they are very similar in terms of their masses and sizes, despite being subjected to external pressures that are several magnitudes greater (~ 108 K cm-3). The fact that > 80% of these cores do not show any signs of star-forming activity in such a high-pressure environment leads us to conclude that this is further evidence of the critical density for star formation being heightened in the CMZ due to turbulence.

  19. Ionized gas pressure correlates with star formation intensity in nearby starbursts

    NASA Astrophysics Data System (ADS)

    Jiang, Tianxing; Malhotra, Sangeeta; Yang, Huan

    2016-06-01

    We estimate the electron density of the ionized gas and thus the thermal pressure in HII regions; and compare that to the SFR (star formation rate) surface density for a combined sample of about 40 green peas and Lyman Break Analogs at z < 0.30. The electron density of the ionized gas is measured from sulfur line ratio ([SII] 6716 / 6731). We find that the SFR surface density is correlated with the electron density and the thermal pressure in HII regions for the star-forming galaxies with SFR surface density above a certain threshold. This work shows quantitatively the correlation between SFR surface density and electron density and that between SFR surface density and the thermal pressure in HII regions for the nearby starburst galaxies. This is consistent with theoretical models of disks (e.g. Kim et al. (2011) if we assume that the thermal pressure in HII regions is comparable to the total diffuse gas pressure at the midplane of the diffuse neutral gas. It is also in agreement with the results from star-forming galaxies at z ~ 2.5. We might infer that the starburst galaxies at low-redshift (z < 0.3) share similar physical properties to the galaxies at high redshift (z ~ 2.5).

  20. Pressure dependence of stabilized Criegee intermediate formation from a sequence of alkenes.

    PubMed

    Drozd, Greg T; Donahue, Neil M

    2011-05-05

    Ozonolysis is a key reaction in atmospheric chemistry, although important details of the behavior of the ozonolysis intermediates are not known. The key intermediate in ozonolysis, the Criegee intermeiate (CI), is known to quickly isomerize, with the favored unimolecular pathway depending on the relative barriers to isomerization. Stabilized Criegee intermediates (SCI), those with energy below any barriers to isomerization, may result from initial formation with low energy or collisional stabilization of high energy CI. Bimolecular reactions of SCI have been proposed to play a role in OH formation and nucleation of new particles, but unimolecular reactions of SCI may well be too fast for these to be significant. We present measurements of the pressure dependence of SCI formation for a set of alkenes utilizing a hexafluoroacetone scavenger. We studied four alkenes (2,3-dimethyl-2-butene (TME), trans-5-decene, cyclohexene, α-pinene) to characterize how size and cyclization (endo vs exo) affect the stability of Criegee intermediates formed in ozonolysis. SCI yields in ozonolysis were measured in a high pressure flow reactor within a range of 30-750 Torr. The linear alkenes show considerable stabilization with trans-5-decene showing 100% stabilization at ∼400 Torr and TME having 65% stabilization at 710 Torr. Extrapolation of the yields for linear alkenes to 0 Torr shows yields significantly above zero, indicating that a fraction of their CI are formed below the barrier to isomerization. CI from endocyclic alkenes show little to no stabilization and appear to have neglible stabilization at 0 Torr. Cyclohexene derived CI showed no stabilization even at 650 Torr, while α-pinene CI had ∼15% stabilization at 740 Torr. Our results show a strong dependence of SCI formation on carbon number; adding just 2 to 3 CI carbons in linear alkenes increases stabilization by a factor of 10. Stabilization for endocyclic alkenes, at atmospheric pressure, begins to occur at a carbon

  1. Direct measurement of the differential pressure during drop formation in a co-flow microfluidic device.

    PubMed

    Xu, Ke; Tostado, Chris P; Xu, Jian-Hong; Lu, Yang-Cheng; Luo, Guang-Sheng

    2014-04-07

    In this study, we developed a new method for the direct measurement of differential pressures in a co-flow junction microfluidic device using a Capillary Laplace Gauge (CLG). The CLG - used inside the microchannel device--was designed using a tapered glass-capillary set up in co-flow junction architecture with a three-phase liquid-liquid-gas system with two flowing liquid phases and an entrained gas phase. By taking advantage of the Laplace equation, basic geometric relations and an integrated image analysis program, the movement of the entrained gas phase with the flow of the liquid-phases is tracked and monitored, allowing the gauge to function as an ultra-sensitive, integrated, differential pressure sensor measuring fluctuations in the liquid-dispersed phase channel pressure as small as tens of Pascals caused by droplet formation. The gauge was used to monitor the drop formation and breakup process in a co-flow junction microfluidic device under different flow conditions across a large range (1 × 10(-3) to 2.0 × 10(-1)) of capillary numbers. In addition to being able to monitor short and long term dispersed phase pressure fluctuation trends for both single drop and large droplet populations, the gauge was also used to clearly identify a transition between the dripping and jetting flow regimes. Overall, the combination of a unique, integrated image analysis program with this new type of sensor serves as a powerful tool with great potential for a variety of different research and industrial applications requiring sensitive microchannel pressure measurements.

  2. The Pegasus Overture alternating-pressure mattress overlay.

    PubMed

    Fox, C

    Pressure sores affect approximately 10% of the adult population and occur in various hospitals and community settings (Department of Health, 1992). It is therefore essential to adopt a logical approach when selecting the optimum piece of equipment for patients at risk of pressure sore development. Alternating-pressure mattresses have been used for many years in both hospitals and community environments to prevent and treat pressure sores. In September 1995, Pegasus Airwave Limited launched a new alternating-pressure mattress overlay, the Overture. It is designed for use with patients who have mobility problems and are at low to medium risk of developing pressure sores or have superficial tissue damage. This article describes the features of the Overture and its suitability for use in different care settings.

  3. When a Sore Throat Is a More Serious Infection

    MedlinePlus

    ... on her hands and feet (often called Hand, Foot, and Mouth disease). Infectious mononucleosis can produce a sore throat, often with marked tonsillitis; however, most young children who are infected with the mononucleosis virus have few or no symptoms. Strep throat is ...

  4. The effects of three modalities on delayed onset muscle soreness.

    PubMed

    Weber, M D; Servedio, F J; Woodall, W R

    1994-11-01

    Delayed onset muscle soreness is a common problem that can interfere with rehabilitation as well as activities of daily living. The purpose of this study was to test the impact of therapeutic massage, upper body ergometry, or microcurrent electrical stimulation on muscle soreness and force deficits evident following a high-intensity eccentric exercise bout. Forty untrained, volunteer female subjects were randomly assigned to one of three treatment groups or to a control group. Exercise consisted of high-intensity eccentric contractions of the elbow flexors. Resistance was reduced as subjects fatigued, until they reached exhaustion. Soreness rating was determined using a visual analog scale. Force deficits were determined by measures of maximal voluntary isometric contraction at 90 degrees of elbow flexion and peak torque for elbow flexion at 60 degrees/sec on a Cybex II isokinetic dynamometer. Maximal voluntary isometric contraction and peak torque were determined at the 0 hour (before exercise) and again at 24 and 48 hours postexercise. Treatments were applied immediately following exercise and again at 24 hours after exercise. The control group subjects rested following their exercise bout. Statistical analysis showed significant increases in soreness rating and significant decreases in force generated when the 0 hour was compared with 24- and 48-hour measures. Further analysis indicated no statistically significant differences between massage, microcurrent electrical stimulation, upper body ergometry, and control groups.

  5. Hemispheric Asymmetry and Pun Comprehension: When Cowboys Have Sore Calves

    ERIC Educational Resources Information Center

    Coulson, Seana; Severens, Els

    2007-01-01

    Event-related potentials (ERPs) were recorded as healthy participants listened to puns such as ''During branding, cowboys have sore calves.'' To assess hemispheric differences in pun comprehension, visually presented probes that were either highly related (COW), moderately related (LEG), or unrelated, were presented in either the left or right…

  6. Recommendations for the Avoidance of Delayed-Onset Muscle Soreness.

    ERIC Educational Resources Information Center

    Szymanski, David J.

    2001-01-01

    Describes the possible causes of delayed-onset muscle soreness (DOMS), which include buildup of lactic acid in muscle, increased intracellular calcium concentration, increased intramuscular inflammation, and muscle fiber and connective tissue damage. Proposed methods to reduce DOMS include warming up before exercise and performing repeated bouts…

  7. Analysis of Pore Pressure and Stress Distribution around a Wellbore Drilled in Chemically Active Elastoplastic Formations

    NASA Astrophysics Data System (ADS)

    Roshan, Hamid; Rahman, S. S.

    2011-09-01

    Drilling in low-permeable reactive shale formations with water-based drilling mud presents significant challenges, particularly in high-pressure and high-temperature environments. In previous studies, several models were proposed to describe the thermodynamic behaviour of shale. Most shale formations under high pressure are expected to undergo plastic deformation. An innovative algorithm including work hardening is proposed in the framework of thermo-chemo-poroelasticity to investigate the effect of plasticity on stresses around the wellbore. For this purpose a finite-element model of coupled thermo-chemo-poro-elastoplasticity is developed. The governing equations are based on the concept of thermodynamics of irreversible processes in discontinuous systems. In order to solve the plastic problem, a single-step backward Euler algorithm containing a yield surface-correction scheme is used to integrate the plastic stress-strain relation. An initial stress method is employed to solve the non-linearity of the plastic equation. In addition, super convergent patch recovery is used to accurately evaluate the time-dependent stress tensor from nodal displacement. The results of this study reveal that thermal and chemical osmosis can significantly affect the fluid flow in low-permeable shale formations. When the salinity of drilling mud is higher than that of pore fluid, fluid is pulled out of the formation by chemical osmotic back flow. Similar results are observed when the temperature of drilling mud is lower than that of the formation fluid. It is found that linear elastic approaches to wellbore stability analysis appear to overestimate the tangential stress around the wellbore and produce more conservative stresses compared to the results of field observation. Therefore, the drilling mud properties obtained from the elastoplastic wellbore stability in shales provide a safer mud weight window and reduce drilling cost.

  8. High-pressure soot formation and diffusion flame extinction characteristics of gaseous and liquid fuels

    NASA Astrophysics Data System (ADS)

    Karatas, Ahmet Emre

    High-pressure soot formation and flame stability characteristics were studied experimentally in laminar diffusion flames. For the former, radially resolved soot volume fraction and temperature profiles were measured in axisymmetric co-flow laminar diffusion flames of pre-vaporized n-heptane-air, undiluted ethylene-air, and nitrogen and carbon dioxide diluted ethylene-air at elevated pressures. Abel inversion was used to re-construct radially resolved data from the line-of-sight spectral soot emission measurements. For the latter, flame extinction strain rate was measured in counterflow laminar diffusion flames of C1-4 alcohols and hydrocarbon fuels of n-heptane, n-octane, iso-octane, toluene, Jet-A, and biodiesel. The luminous flame height, as marked by visible soot radiation, of the nitrogen- and helium-diluted n-heptane and nitrogen- and carbon dioxide-diluted ethylene flames stayed constant at all pressures. In pure ethylene flames, flame heights initially increased with pressure, but changed little above 5 atm. The maximum soot yield as a function of pressure in nitrogen-diluted n-heptane diffusion flames indicate that n-heptane flames are slightly more sensitive to pressure than gaseous alkane hydrocarbon flames at least up to 7 atm. Ethylene's maximum soot volume fractions were much higher than those of ethane and n-heptane diluted with nitrogen (fuel to nitrogen mass flow ratio is about 0.5). Pressure dependence of the peak carbon conversion to soot, defined as the percentage of fuel's carbon content converted to soot, was assessed and compared to previous measurements with other gaseous fuels. Maximum soot volume fractions were consistently lower in carbon dioxide-diluted flames between 5 and 15 atm but approached similar values to those in nitrogen-diluted flames at 20 atm. This observation implies that the chemical soot suppression effect of carbon dioxide, previously demonstrated at atmospheric pressure, is also present at elevated pressures up to 15 atm

  9. Soot Formation in Laminar Acetylene/Air Diffusion Flames at Atmospheric Pressure. Appendix H

    NASA Technical Reports Server (NTRS)

    Xu, F.; Faeth, G. M.; Yuan, Z.-G. (Technical Monitor); Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2001-01-01

    The flame structure and soot-formation (soot nucleation and growth) properties of axisymmetric laminar coflowing jet diffusion flames were studied experimentally. Test conditions involved acetylene-nitrogen jets burning in coflowing air at atmospheric pressure. Measurements were limited to the axes of the flames and included soot concentrations, soot temperatures, soot structure, major gas species concentrations, radical species (H, OH, and O) concentrations, and gas velocities. The results show that as distance increases along the axes of the flames, detectable soot formation begins when significant H concentrations are present, and ends when acetylene concentrations become small. Species potentially associated with soot oxidation-O2, CO2, H2O, O, and OH-are present throughout the soot-formation region so that soot formation and oxidation proceed at the same time. Strong rates of soot growth compared to soot nucleation early in the soot-formation process, combined with increased rates of soot nucleation and oxidation as soot formation proceeds, causes primary soot particle diameters to reach a maximum relatively early in the soot-formation process. Aggregation of primary soot particles proceeds, however, until the final stages of soot oxidation. Present measurements of soot growth (corrected for soot oxidation) in laminar diffusion flames were consistent with earlier measurements of soot growth in laminar premixed flames and exhibited encouraging agreement with existing hydrogen-abstraction/carbon-addition (HACA) soot growth mechanisms in the literature that were developed based on measurements within laminar premixed flames. Measured primary soot particle nucleation rates in the present laminar diffusion flames also were consistent with corresponding rates measured in laminar premixed flames and yielded a crude correlation in terms of acetylene and H concentrations and the temperature.

  10. Soot Formation in Laminar Acetylene/Air Diffusion Flames at Atmospheric Pressure. Appendix J

    NASA Technical Reports Server (NTRS)

    Xu, F.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2001-01-01

    The flame structure and soot-formation (soot nucleation and growth) properties of axisymmetric laminar coflowing jet diffusion flames were studied experimentally. Test conditions involved acetylene-nitrogen jets burning in coflowing air at atmospheric pressure. Measurements were limited to the axes of the flames and included soot concentrations, soot temperatures, soot structure, major gas species concentrations, radical species (H, OH, and O) concentrations, and gas velocities. The results show that as distance increases along the axes of the flames, detectable soot formation begins when significant H concentrations are present, and ends when acetylene concentrations become small. Species potentially associated with soot oxidation--O2, CO2, H2O, O, and OH-are present throughout the soot-formation region so that soot formation and oxidation proceed at the same time. Strong rates of soot growth compared to soot nucleation early in the soot-formation process, combined with increased rates of soot nucleation and oxidation as soot formation proceeds, causes primary soot particle diameters to reach a maximum relatively early in the soot-formation process. Aggregation of primary soot particles proceeds, however, until the final stages of soot oxidation. Present measurements of soot growth (corrected for soot oxidation) in laminar diffusion flames were consistent with earlier measurements of soot growth in laminar premixed flames and exhibited encouraging agreement with existing hydrogen-abstraction/carbon-addition (HACA) soot growth mechanisms in the literature that were developed based on measurements within laminar premixed flames. Measured primary soot particle nucleation rates in the present laminar diffusion flames also were consistent with corresponding rates measured in laminar premixed flames and yielded a crude correlation in terms of acetylene and H concentrations and the temperature.

  11. Soot Formation in Laminar Acetylene/Air Diffusion Flames at Atmospheric Pressure. Appendix C

    NASA Technical Reports Server (NTRS)

    Xu, F.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2000-01-01

    The flame structure and soot-formation (soot nucleation and growth) properties of axisymmetric laminar coflowing jet diffusion flames were studied experimentally. Test conditions involved acetylene-nitrogen jets burning in coflowing air at atmospheric pressure. Measurements were limited to the axes of the flames and included soot concentrations, soot temperatures, soot structure, major gas species concentrations, radical species (H, OH, and O) concentrations, and gas velocities. The results show that as distance increases along the axes of the flames, detectable soot formation begins when significant H concentrations are present, and ends when acetylene concentrations become small. Species potentially associated with soot oxidation-O2, CO2, H2O, O, and OH-are present throughout the soot-formation region so that soot formation and oxidation proceed at the same time. Strong rates of soot growth compared to soot nucleation early in the soot-formation process, combined with increased rates of soot nucleation and oxidation as soot formation proceeds, causes primary soot particle diameters to reach a maximum relatively early in the soot-formation process. Aggregation of primary soot particles proceeds, however, until the final stages of soot oxidation. Present measurements of soot growth (corrected for soot oxidation) in laminar diffusion flames were consistent with earlier measurements of soot growth in laminar premixed flames and exhibited encouraging agreement with existing hydrogen-abstraction/carbon-addition (HACA) soot growth mechanisms in the literature that were developed based on measurements within laminar premixed flames. Measured primary soot particle nucleation rates in the present laminar diffusion flames also were consistent with corresponding rates measured in laminar premixed flames and yielded a crude correlation in terms of acetylene and H concentrations and the temperature.

  12. Formation and properties of water from quartz and hydrogen at high pressure and temperature

    NASA Astrophysics Data System (ADS)

    Futera, Zdenek; Yong, Xue; Pan, Yuanming; Tse, John S.; English, Niall J.

    2017-03-01

    Quartz, as the most stable low-pressure polymorph of silica (SiO2), is widely abundant in Earth's crust and mantle, exhibiting relatively high chemical stability. Although silica is only slightly soluble in water at ambient conditions, producing silicon-based weakly acidic compounds, Shinozaki et al. (2014) have shown recently that water itself can be formed by dissolution of SiO2 in H2 fluid under high- temperature and pressure conditions. Here, we have simulated this process via molecular-dynamics techniques based on a reactive force-field description of the Si O2 /H2 interface. Diffusion of the H2 fluid into the quartz crystal lattice was observed upon increasing temperature and pressure, followed by interaction of dissociated, atomic hydrogen with oxygen atoms in the SiO2 lattice, disrupting the lattice and leading to the formation of water. Interestingly, water is evolved in the subsurface region of the silica, and it remains confined there, isolated from the hydrogen fluid, which corresponds precisely to the ice-like spectroscopic patterns observed experimentally. The over-pressured water formed from quartz and H2 is a possible trigger for nucleating enigmatic deep earthquakes in the continental mantle lithosphere.

  13. Formation risk of toxic and other unwanted compounds in pressure-assisted thermally processed foods.

    PubMed

    Bravo, K Segovia; Ramírez, R; Durst, R; Escobedo-Avellaneda, Z J; Welti-Chanes, J; Sanz, P D; Torres, J A

    2012-01-01

    Consumers demand, in addition to excellent eating quality, high standards of microbial and chemical safety in shelf-stable foods. This requires improving conventional processing technologies and developing new alternatives such as pressure-assisted thermal processing (PATP). Studies in PATP foods on the kinetics of chemical reactions at temperatures (approximately 100 to 120 °C) inactivating bacterial spores in low-acid foods are severely lacking. This review focuses on a specific chemical safety risk in PATP foods: models predicting if the activation volume value (V(a) ) of a chemical reaction is positive or negative, and indicating if the reaction rate constant will decrease or increase with pressure, respectively, are not available. Therefore, the pressure effect on reactions producing toxic compounds must be determined experimentally. A recent model solution study showed that acrylamide formation, a potential risk in PATP foods, is actually inhibited by pressure (that is, its V(a) value must be positive). This favorable finding was not predictable and still needs to be confirmed in food systems. Similar studies are required for other reactions producing toxic compounds including polycyclic aromatic hydrocarbons, heterocyclic amines, N-nitroso compounds, and hormone like-peptides. Studies on PATP inactivation of prions, and screening methods to detect the presence of other toxicity risks of PATP foods, are also reviewed.

  14. Formation of carbon nanoparticle using Ar+CH4 high pressure nanosecond discharges

    NASA Astrophysics Data System (ADS)

    Koga, K.; Dong, X.; Iwashita, S.; Czarnetzki, U.; Shiratani, M.

    2014-06-01

    We have studied formation of carbon nanoparticles using Ar+CH4 high pressure nanosecond discharge non-thermal plasmas. Transition pressure from uniform glow discharges to filamentary ones was clarified to obtain conditions under which uniform glow discharges are sustained. We have produced nanoparticles using the glow discharges, and then we have collected nanoparticles on the grounded electrode by the filtered vacuum collection method. Size distribution analysis reveals that the CH4 concentration is an important parameter in controlling nanoparticle growth. We have also studied film deposition on the powered electrode and the grounded electrode. The deposition rate on the powered electrode is 7 times higher than that on the grounded electrode. Optical emission observations suggest that radical generation rate near the powered electrode is twice higher than that near the grounded electrode, leading to high deposition rate on the powered electrode.

  15. Mixing unmixables: Unexpected formation of Li-Cs alloys at low pressure.

    PubMed

    Desgreniers, Serge; Tse, John S; Matsuoka, Takahiro; Ohishi, Yasuo; Tse, Justin J

    2015-10-01

    Contrary to the empirical Miedema and Hume-Rothery rules and a recent theoretical prediction, we report experimental evidence on the formation of Li-Cs alloys at very low pressure (>0.1 GPa). We also succeeded in synthesizing a pure nonstoichiometric and ordered crystalline phase from an approximately equimolar mixture and resolved its structure using the maximum entropy method. The new alloy has a primitive cubic cell with the Li atom situated in the center and the Cs at the corners. This structure is stable to at least 10 GPa and has an anomalously high coefficient of thermal expansion at low pressure. Analysis of the valence charge density shows that electrons are donated from Cs to the Li "p"-orbitals, resulting in a rare formal oxidation state of -1 for Li. The observation indicates the diversity in the bonding of the seeming simple group I Li element.

  16. Combined V-Y Fasciocutaneous Advancement and Gluteus Maximus Muscle Rotational Flaps for Treating Sacral Sores

    PubMed Central

    Choi, Eun Jeong; Moon, Suk Ho; Lee, Yoon Jae

    2016-01-01

    The sacral area is the most common site of pressure sore in bed-ridden patients. Though many treatment methods have been proposed, a musculocutaneous flap using the gluteus muscles or a fasciocutaneous flap is the most popular surgical option. Here, we propose a new method that combines the benefits of these 2 methods: combined V-Y fasciocutaneous advancement and gluteus maximus muscle rotational flaps. A retrospective review was performed for 13 patients who underwent this new procedure from March 2011 to December 2013. Patients' age, sex, accompanying diseases, follow-up duration, surgical details, complications, and recurrence were documented. Computed tomography was performed postoperatively at 2 to 4 weeks and again at 4 to 6 months to identify the thickness and volume of the rotational muscle portion. After surgery, all patients healed within 1 month; 3 patients experienced minor complications. The average follow-up period was 13.6 months, during which time 1 patient had a recurrence (recurrence rate, 7.7%). Average thickness of the rotated muscle was 9.43 mm at 2 to 4 weeks postoperatively and 9.22 mm at 4 to 6 months postoperatively (p = 0.087). Muscle thickness had not decreased, and muscle volume was relatively maintained. This modified method is relatively simple and easy for reconstructing sacral sores, provides sufficient padding, and has little muscle donor-site morbidity. PMID:27366755

  17. Formation of the Yakuno ophiolite; accretionary subduction under medium-pressure-type metamorphic conditions

    NASA Astrophysics Data System (ADS)

    Osozawa, Soichi; Takeuchi, Hiroshi; Koitabashi, Toru

    2004-11-01

    The notion that the Yakuno ophiolite and overlying Maizuru Group represents an accretionary prism formed during the Permian evolution of Japan on the Yakuno eruptive sequence, association of hemipelagic mudstone with silicic tuff, exotic fossiliferous limestones derived from previously accreted sea-mounts, upward coarsening of sequences terrigenous sandstone and conglomerate, and mildly deformed Permian and Triassic forearc basin formations. The most important indicator, however, is the seaward imbrication and repetition observed in both the Maizuru Group and the ophiolite itself. D1 deformation structures include axial-planar foliations (pressure-solution cleavage for the Maizuru Group and granulite-amphibolite metamorphic layering in the ophiolite), flattening type strain, symmetric pressure shadows and fringes, and isoclinal folds showing axial-planar foliations and thrust faulting at their overturned limb. The exceptional asymmetry observed indicates seaward-directed shearing near the thrust, while D1 structures in the Maizuru zone are explained by off-scraping, above the basal decollement. The later Jurassic D2 kink fold structure includes a first-order asymmetric kink with a brittle thrust at its overturned limb, more-or-less coeval with M2 retrograde metamorphism. Medium-pressure M1 prograde metamorphism in the Yakuno ophiolite produced layering of granulite and amphibolite, and in the Maizuru Group, formation of illite along pressure-solution cleavage of mudstones. The metamorphic grade is controlled by the stratigraphic relationships and appears typical of that in ocean floor regions. However, there was only one episode of M1 prograde metamorphism which occurred contemporaneously with D1 off-scraping. Given that subduction zones are normally characterized by high P/ T metamorphic regimes, the observed P/ T history appears to reflect relatively unusual conditions. Such high thermal gradients may plausibly reflect the approach of a young, hot oceanic plate

  18. Equatorial disk formation around rotating stars due to ram pressure confinement by the stellar wind

    NASA Technical Reports Server (NTRS)

    Bjorkman, J. E.; Cassinelli, J. P.

    1993-01-01

    The axisymmetric 2D supersonic solution of a rotating, radiation-driven stellar wind presently obtained by a simple approximation predicts the formation of a dense equatorial disk, when the star's rotation rate lies above a threshold value that depends on the ratio of the wind's terminal speed to the escape speed of the star. The disk is formed because the trajectories of the wind leaving the stellar surface at high latitudes carry it down to the equatorial plane; there, the material passes through a standing oblique shock atop the disk; it is therefore the ram pressure of the polar wind that compresses and confines the disk.

  19. Subnanosecond processes in the stage of breakdown formation in gas at a high pressure

    NASA Astrophysics Data System (ADS)

    Korolev, Yu. D.; Bykov, N. M.; Ivanov, S. N.

    2008-12-01

    Results are presented from experimental studies of the prebreakdown stage of a discharge in nitrogen at pressures of a few tens of atmospheres, gap voltages higher than 140 kV, and a voltage rise time of about 1 ns. Breakdown occurs at the front of the voltage pulse; i.e., the time of breakdown formation is shorter than the front duration. It is shown that, in gaps with a nonuniform electric field, the breakdown formation time is mainly determined by the time of avalanche development to the critical number of charge carriers. The subsequent stages of breakdown (the development of the ionization wave and the buildup of the conductivity in the weakly conducting channel bridging the gap) turn out to be shorter than this time or comparable to it.

  20. Self-regulating galaxy formation. Part 1: HII disk and Lyman alpha pressure

    NASA Technical Reports Server (NTRS)

    Cox, D. P.

    1983-01-01

    Assuming a simple but physically based prototype for behavior of interstellar material during formation of a disk galaxy, coupled with the lowest order description of infall, a scenario is developed for self-regulated disk galaxy formation. Radiation pressure, particularly that of Lyman depha (from fluorescence conversion Lyman continuum), is an essential component, maintaining an inflated disk and stopping infall when only a small fraction of the overall perturbation has joined the disk. The resulting galaxies consist of a two dimensional family whose typical scales and surface density are expressable in terms of fundamental constants. The model leads naturally to galaxies with a rich circumgalactic environment and flat rotation curves (but is weak in its analysis of the subsequent evolution of halo material).

  1. Periodic seepage face formation and water pressure distribution along a vertical boundary of an aquifer

    NASA Astrophysics Data System (ADS)

    Jazayeri Shoushtari, Seyed Mohammad Hossein; Nielsen, Peter; Cartwright, Nick; Perrochet, Pierre

    2015-04-01

    Detailed measurements of the piezometric head from sand flume experiments of an idealised coastal aquifer forced by a simple harmonic boundary condition across a vertical boundary are presented. The measurements focus on the pore pressures very close to the interface (x = 0.01m) and throw light on the details of the boundary condition, particularly with respect to meniscus suction and seepage face formation during the falling tide. Between the low and the mean water level, the response is consistent with meniscus suction free models in terms of both the vertical mean head and oscillation amplitude profiles and is consistent with the observation that this area of the interface was generally within the seepage face. Above the mean water level, the influence of meniscus formation is significant with the mean pressure head being less than that predicted by capillary free theory and oscillation amplitudes decaying faster than predicted by suction free models. The reduced hydraulic conductivity in this area due to partial drainage of pores on the falling tide also causes a delay in the response to the rising tide. The combined influence of seepage face formation, meniscus suction and reduced hydraulic conductivity generate higher harmonics with amplitudes of up to 26% of the local main harmonic. To model the influence of seepage face formation and meniscus suction a numerical solution of the Richards' equation was developed and evaluated against the data. The model-data comparison shows a good agreement with the behaviour high above the water table sensitive to the choice of moisture retention parameters.

  2. Significant Enhancement of H2 Formation in Disk Galaxies under Strong Ram Pressure

    NASA Astrophysics Data System (ADS)

    Henderson, Benjamin; Bekki, Kenji

    2016-05-01

    We show for the first time that H2 formation on dust grains can be enhanced in disk galaxies under strong ram pressure (RP). We numerically investigate how the time evolution of H i and H2 components in disk galaxies orbiting a group/cluster of galaxies can be influenced by the hydrodynamical interaction between the gaseous components of the galaxies and the hot intracluster medium. We find that compression of H i caused by RP increases H2 formation in disk galaxies before RP rapidly strips H i, cutting off the fuel supply and causing a drop in H2 density. We also find that the level of this H2 formation enhancement in a disk galaxy under RP depends on the mass of its host cluster dark matter halo, the initial positions and velocities of the disk galaxy, and the disk inclination angle with respect to the orbital plane. We demonstrate that dust growth is a key factor in the evolution of the H i and H2 mass in disk galaxies under strong RP. We discuss how the correlation between H2 fractions and surface gas densities of disk galaxies evolves with time in the galaxies under RP. We also discuss whether galaxy-wide star formation rates (SFRs) in cluster disk galaxies can be enhanced by RP if the SFRs depend on H2 densities.

  3. Sore throat: effective communication delivers improved diagnosis, enhanced self-care and more rational use of antibiotics.

    PubMed

    van der Velden, A W; Bell, J; Sessa, A; Duerden, M; Altiner, A

    2013-11-01

    The majority of throat infections are of viral origin and resolve without antibiotic treatment. Despite this, antibiotic use for sore throat infections remains high, partly because it is difficult to determine when antibiotics may be useful, on the basis of physical findings alone. Antibiotics may be beneficial in bacterial throat infections under certain clinical and epidemiological circumstances; however, even many of those infections in which bacteria play a role do resolve just as quickly without antibiotics. Furthermore, non-medical factors such as patient expectations and patient pressure are also important drivers of antibiotic use. To address these issues, a behavioural change is required that can be facilitated by improved communication between primary healthcare providers and patients. In this article, we provide doctors, nurses and pharmacy staff, working in primary care or in the community, with a structured approach to sore throat management, with the aim of educating and empowering patients to self-manage their condition. The first component of this approach involves identifying and addressing patients' expectations and concerns with regard to their sore throat and eliciting their opinion on antibiotics. The second part is dedicated to a pragmatic assessment of the severity of the condition, with attention to red-flag symptoms and risk factors for serious complications. Rather than just focusing on the cause (bacterial or viral) of the upper respiratory tract infections as a rationale for antibiotic use, healthcare providers should instead consider the severity of the patient's condition and whether they are at high risk of complications. The third part involves counselling patients on effective self-management options and providing information on the expected clinical course. Such a structured approach to sore throat management, using empathetic, non-paternalistic language, combined with written patient information, will help to drive patient

  4. A Computational, Tissue-Realistic Model of Pressure Ulcer Formation in Individuals with Spinal Cord Injury.

    PubMed

    Ziraldo, Cordelia; Solovyev, Alexey; Allegretti, Ana; Krishnan, Shilpa; Henzel, M Kristi; Sowa, Gwendolyn A; Brienza, David; An, Gary; Mi, Qi; Vodovotz, Yoram

    2015-06-01

    People with spinal cord injury (SCI) are predisposed to pressure ulcers (PU). PU remain a significant burden in cost of care and quality of life despite improved mechanistic understanding and advanced interventions. An agent-based model (ABM) of ischemia/reperfusion-induced inflammation and PU (the PUABM) was created, calibrated to serial images of post-SCI PU, and used to investigate potential treatments in silico. Tissue-level features of the PUABM recapitulated visual patterns of ulcer formation in individuals with SCI. These morphological features, along with simulated cell counts and mediator concentrations, suggested that the influence of inflammatory dynamics caused simulations to be committed to "better" vs. "worse" outcomes by 4 days of simulated time and prior to ulcer formation. Sensitivity analysis of model parameters suggested that increasing oxygen availability would reduce PU incidence. Using the PUABM, in silico trials of anti-inflammatory treatments such as corticosteroids and a neutralizing antibody targeted at Damage-Associated Molecular Pattern molecules (DAMPs) suggested that, at best, early application at a sufficiently high dose could attenuate local inflammation and reduce pressure-associated tissue damage, but could not reduce PU incidence. The PUABM thus shows promise as an adjunct for mechanistic understanding, diagnosis, and design of therapies in the setting of PU.

  5. Preparation of monodisperse microspheres from the Laplace pressure induced droplet formation in micromolds

    NASA Astrophysics Data System (ADS)

    Choi, Chang-Hyung; Kim, Jongmin; Kang, Sung-Min; Lee, Jinkee; Lee, Chang-Soo

    2013-03-01

    Monodisperse microspheres play critical roles in many applications such as micro-electromechanical systems (MEMS), chemical release systems, optical materials and various biological applications. Although microfluidic systems have been developed for producing monodisperse microspheres, it still definitely requires pressure driven flow for continuous fluid injection as well as use of surfactant to achieve their uniformity. Here, we present a novel molding method that generates monodisperse microspheres through surface-tension-induced flow. Two immiscible fluids that consist of photocurable monomer and hydrophobic oil are sequentially applied onto the mold. The mold geometry results in Laplace pressure induced droplet formation, and these droplets formed are individually localized into each micromold. Photopolymerization of the droplets allow for the formation of polymer microspheres with narrow size distribution (CV =1.9%). We obtain the microspheres with diameter ranging from 20 to 300 μm by modulating mold dimensions. We provide a synthesis method to produce microspheres in micromolds for various reaction schemes: UV-polymerization, sol-gel reactions and colloidal assemblies.

  6. Low-pressure clathrate-hydrate formation in amorphous astrophysical ice analogs

    NASA Technical Reports Server (NTRS)

    Blake, D. F.; Allamandola, L. J.; Sandford, S.; Hudgins, D.; Freund, F.

    1991-01-01

    In modeling cometary ice, the properties of clathrate hydrates were used to explain anomalous gas release at large radial distances from the Sun, and the retention of particular gas inventories at elevated temperatures. Clathrates may also have been important early in solar system history. However, there has never been a reasonable mechanism proposed for clathrate formation under the low pressures typical of these environments. For the first time, it was shown that clathrate hydrates can be formed by warming and annealing amorphous mixed molecular ices at low pressures. The complex microstructures which occur as a result of clathrate formation from the solid state may provide an explanation for a variety of unexplained phenomena. The vacuum and imaging systems of an Hitachi H-500H Analytical Electron Microscope was modified to study mixed molecular ices at temperatures between 12 and 373 K. The resulting ices are characterized by low-electron dose Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED). The implications of these results for the mechanical and gas release properties of comets are discussed. Laboratory IR data from similar ices are presented which suggest the possibility of remotely observing and identifying clathrates in astrophysical objects.

  7. High Pressure and Temperature Core Formation as an Alternative to the "Late Veneer" Hypothesis

    NASA Technical Reports Server (NTRS)

    Righter, Kevin; Pando, K.; Humayun, M.; Danielson, L.

    2011-01-01

    The highly siderophile elements (HSE; Re, Au and the Platinum Group Elements - Pd Pt, Rh, Ru, Ir, Os) are commonly utilized to constrain accretion processes in terrestrial differentiated bodies due to their affinity for FeNi metal [1]. These eight elements exhibit highly siderophile behavior, but nonetheless have highly diverse metal-silicate partition coefficients [2]. Therefore the near chondritic relative concentrations of HSEs in the terrestrial and lunar mantles, as well as some other bodies, are attributed to late accretion rather than core formation [1]. Evaluation of competing theories, such as high pressure metal-silicate partitioning or magma ocean hypotheses has been hindered by a lack of relevant partitioning data for this group of eight elements. In particular, systematic studies isolating the effect of one variable (e.g. temperature or melt compositions) are lacking. Here we undertake new experiments on all eight elements, using Fe metal and FeO-bearing silicate melts at fixed pressure, but variable temperatures. These experiments, as well as some additional planned experiments should allow partition coefficients to be more accurately calculated or estimated at the PT conditions and compositions at which core formation is thought to have occurred.

  8. The collaborative effect of ram pressure and merging on star formation and stripping fraction

    NASA Astrophysics Data System (ADS)

    Bischko, J. C.; Steinhauser, D.; Schindler, S.

    2015-04-01

    Aims: We investigate the effect of ram pressure stripping (RPS) on several simulations of merging pairs of gas-rich spiral galaxies. We are concerned with the changes in stripping efficiency and the time evolution of the star formation rate. Our goal is to provide an estimate of the combined effect of merging and RPS compared to the influence of the individual processes. Methods: We make use of the combined N-body/hydrodynamic code GADGET-2. The code features a threshold-based statistical recipe for star formation, as well as radiative cooling and modeling of galactic winds. In our simulations, we vary mass ratios between 1:4 and 1:8 in a binary merger. We sample different geometric configurations of the merging systems (edge-on and face-on mergers, different impact parameters). Furthermore, we vary the properties of the intracluster medium (ICM) in rough steps: the speed of the merging system relative to the ICM between 500 and 1000 km s-1, the ICM density between 10-29 and 10-27 g cm-3, and the ICM direction relative to the mergers' orbital plane. Ram pressure is kept constant within a simulation time period, as is the ICM temperature of 107 K. Each simulation in the ICM is compared to simulations of the merger in vacuum and the non-merging galaxies with acting ram pressure. Results: Averaged over the simulation time (1 Gyr) the merging pairs show a negligible 5% enhancement in SFR, when compared to single galaxies under the same environmental conditions. The SFRs peak at the time of the galaxies first fly-through. There, our simulations show SFRs of up to 20 M⊙ yr-1 (compared to 3 M⊙ yr-1 of the non-merging galaxies in vacuum). In the most extreme case, this constitutes a short-term (<50 Myr) SFR increase of 50 % over the non-merging galaxies experiencing ram pressure. The wake of merging galaxies in the ICM typically has a third to half the star mass seen in the non-merging galaxies and 5% to 10% less gas mass. The joint effect of RPS and merging, according

  9. Isotope mass balances in deep formations: How to consider the influence of pressure, temperature and salinity

    NASA Astrophysics Data System (ADS)

    Becker, Veith; Myrttinen, Anssi; Barth, Johannes A. C.

    2010-05-01

    Stable carbon isotopes are a sensitive tool to trace migration and to quantify mixing of CO2 from different sources. This technique is well described for application at the surface and under close-to-surface conditions. However, in order to use isotope mass balances when monitoring the fate of CO2 at carbon storage sites, some distinctive characteristics of deep formations have to be considered. High pressures (from 30 to 200 bar), temperatures (up to over 120 ° C) and salinities (approx. 100 to 400 g/L) influence the carbonate equilibrium as activities, fugacities and the stoichiometric equilibrium constants (fCO2, Kcalcite*, K1*, K2*) change with these parameters. Furthermore, isotopic fractionation is also affected by these parameters. Various relations are published, describing these dependencies with approaches of different complexity and exactness. In this field of application, available sampling data is usually limited, so that averaging and interpolation of input data may lead to noticeable error ranges. Under these conditions, the most elaborated algorithms do not necessarily perform better than more simple ones with respect to the overall error of the calculations. This work therefore compares the available approaches to describe temperature, pressure and salinity dependence in carbonate equilibrium calculations, as well as carbon isotope fractionation in this process with respect to the best ratio of accuracy in carbon storage site monitoring applications. It stands out that the fugacity and the stoichiometric constants involved in DIC-speciation are heavily influenced by pressure, temperature and salinity in general, whereas the individual composition of the solution may be simplified, at least for NaCl-type brines. With respect to fractionation, temperature plays a key role; pressure and salinity variations contribute to the species distribution only to a small amount. This study was conducted as a part of the R&D programme CLEAN, which is funded by

  10. Volume and expansivity changes of micelle formation measured by pressure perturbation calorimetry.

    PubMed

    Fan, Helen Y; Nazari, Mozhgan; Chowdhury, Saria; Heerklotz, Heiko

    2011-03-01

    We present the application of pressure perturbation calorimetry (PPC) as a new method for the volumetric characterization of the micelle formation of surfactants. The evaluation is realized by a global fit of PPC curves at different surfactant concentration ranging, if possible, from below to far above the CMC. It is based on the knowledge of the temperature dependence of the CMC, which can for example be characterized by isothermal titration calorimetry. We demonstrate the new approach for decyl-β-maltopyranoside (DM). It shows a strong volume increase upon micelle formation of 16 ± 2.5 mL/mol (+4%) at 25 °C, and changes with temperature by -0.1 mL/(mol K). The apparent molar expansivity (E(S)) decreases upon micelle formation from 0.44 to 0.31 mL/(mol K) at 25 °C. Surprisingly, the temperature dependence of the expansivity of DM in solution (as compared with that of maltose) does not agree with the principal behavior described for polar (E(S)(T) decreasing) and hydrophobic (E(S)(T) increasing) solutes or moieties before. The results are discussed in terms of changes in hydration of the molecules and internal packing of the micelles and compared with the volumetric effects of transitions of proteins, DNA, lipids, and polymers.

  11. Ozone kinetics in low-pressure discharges: vibrationally excited ozone and molecule formation on surfaces

    NASA Astrophysics Data System (ADS)

    Marinov, Daniil; Guerra, Vasco; Guaitella, Olivier; Booth, Jean-Paul; Rousseau, Antoine

    2013-10-01

    A combined experimental and modeling investigation of the ozone kinetics in the afterglow of pulsed direct current discharges in oxygen is carried out. The discharge is generated in a cylindrical silica tube of radius 1 cm, with short pulse durations between 0.5 and 2 ms, pressures in the range 1-5 Torr and discharge currents ˜40-120 mA. Time-resolved absolute concentrations of ground-state atoms and ozone molecules were measured simultaneously in situ, by two-photon absorption laser-induced fluorescence and ultraviolet absorption, respectively. The experiments were complemented by a self-consistent model developed to interpret the results and, in particular, to evaluate the roles of vibrationally excited ozone and of ozone formation on surfaces. It is found that vibrationally excited ozone, O_3^{*} , plays an important role in the ozone kinetics, leading to a decrease in the ozone concentration and an increase in its formation time. In turn, the kinetics of O_3^{*} is strongly coupled with those of atomic oxygen and O2(a 1Δg) metastables. Ozone formation at the wall does not contribute significantly to the total ozone production under the present conditions. Upper limits for the effective heterogeneous recombination probability of O atoms into ozone are established.

  12. Salt stress induces the formation of a novel type of 'pressure wood' in two Populus species.

    PubMed

    Janz, Dennis; Lautner, Silke; Wildhagen, Henning; Behnke, Katja; Schnitzler, Jörg-Peter; Rennenberg, Heinz; Fromm, Jörg; Polle, Andrea

    2012-04-01

    • Salinity causes osmotic stress and limits biomass production of plants. The goal of this study was to investigate mechanisms underlying hydraulic adaptation to salinity. • Anatomical, ecophysiological and transcriptional responses to salinity were investigated in the xylem of a salt-sensitive (Populus × canescens) and a salt-tolerant species (Populus euphratica). • Moderate salt stress, which suppressed but did not abolish photosynthesis and radial growth in P. × canescens, resulted in hydraulic adaptation by increased vessel frequencies and decreased vessel lumina. Transcript abundances of a suite of genes (FLA, COB-like, BAM, XET, etc.) previously shown to be activated during tension wood formation, were collectively suppressed in developing xylem, whereas those for stress and defense-related genes increased. A subset of cell wall-related genes was also suppressed in salt-exposed P. euphratica, although this species largely excluded sodium and showed no anatomical alterations. Salt exposure influenced cell wall composition involving increases in the lignin : carbohydrate ratio in both species. • In conclusion, hydraulic stress adaptation involves cell wall modifications reciprocal to tension wood formation that result in the formation of a novel type of reaction wood in upright stems named 'pressure wood'. Our data suggest that transcriptional co-regulation of a core set of genes determines reaction wood composition.

  13. Ear Acupuncture for Acute Sore Throat: A Randomized Controlled Trial

    DTIC Science & Technology

    2014-09-26

    SEP 2014 2. REPORT TYPE Final 3. DATES COVERED 4. TITLE AND SUBTITLE Ear acupuncture for acute sore throat. A randomized controlled trial...Auncular Acupuncture is a low risk option for acute pain control •Battlefield acupuncture (BFA) IS a specific auncular acupuncture technique •BFA IS...Strengths: Prospect1ve RCT •Weaknesses Small sample stze. no sham acupuncture performed, patients not blinded to treatment •Th1s study represents an

  14. Modulation in voluntary neural drive in relation to muscle soreness

    PubMed Central

    Bringard, A.; Puchaux, K.; Noakes, T. D.; Perrey, S.

    2007-01-01

    The aim of this study was to investigate whether (1) spinal modulation would change after non-exhausting eccentric exercise of the plantar flexor muscles that produced muscle soreness and (2) central modulation of the motor command would be linked to the development of muscle soreness. Ten healthy subjects volunteered to perform a single bout of backward downhill walking exercise (duration 30 min, velocity 1 ms−1, negative grade −25%, load 12% of body weight). Neuromuscular test sessions [H-reflex, M-wave, maximal voluntary torque (MVT)] were performed before, immediately after, as well as 1–3 days after the exercise bout. Immediately after exercise there was a −15% decrease in MVT of the plantar flexors partly attributable to an alteration in contractile properties (−23% in electrically evoked mechanical twitch). However, MVT failed to recover before the third day whereas the contractile properties had significantly recovered within the first day. This delayed recovery of MVT was likely related to a decrement in voluntary muscle drive. The decrease in voluntary activation occurred in the absence of any variation in spinal modulation estimated from the H-reflex. Our findings suggest the development of a supraspinal modulation perhaps linked to the presence of muscle soreness. PMID:17978834

  15. Whole-Body Vibration and the Prevention and Treatment of Delayed-Onset Muscle Soreness

    PubMed Central

    Aminian-Far, Atefeh; Hadian, Mohammad-Reza; Olyaei, Gholamreza; Talebian, Saeed; Bakhtiary, Amir Hoshang

    2011-01-01

    Abstract Context: Numerous recovery strategies have been used in an attempt to minimize the symptoms of delayed-onset muscle soreness (DOMS). Whole-body vibration (WBV) has been suggested as a viable warm-up for athletes. However, scientific evidence to support the protective effects of WBV training (WBVT) on muscle damage is lacking. Objective: To investigate the acute effect of WBVT applied before eccentric exercise in the prevention of DOMS. Design: Randomized controlled trial. Setting: University laboratory. Patients or Other Participants: A total of 32 healthy, untrained volunteers were randomly assigned to either the WBVT (n  =  15) or control (n  =  17) group. Intervention(s): Volunteers performed 6 sets of 10 maximal isokinetic (60°/s) eccentric contractions of the dominant-limb knee extensors on a dynamometer. In the WBVT group, the training was applied using a vibratory platform (35 Hz, 5 mm peak to peak) with 100° of knee flexion for 60 seconds before eccentric exercise. No vibration was applied in the control group. Main Outcome Measure(s): Muscle soreness, thigh circumference, and pressure pain threshold were recorded at baseline and at 1, 2, 3, 4, 7, and 14 days postexercise. Maximal voluntary isometric and isokinetic knee extensor strength were assessed at baseline, immediately after exercise, and at 1, 2, 7, and 14 days postexercise. Serum creatine kinase was measured at baseline and at 1, 2, and 7 days postexercise. Results: The WBVT group showed a reduction in DOMS symptoms in the form of less maximal isometric and isokinetic voluntary strength loss, lower creatine kinase levels, and less pressure pain threshold and muscle soreness (P < .05) compared with the control group. However, no effect on thigh circumference was evident (P < .05). Conclusions: Administered before eccentric exercise, WBVT may reduce DOMS via muscle function improvement. Further investigation should be undertaken to ascertain the effectiveness of WBVT in

  16. Foam Rolling for Delayed-Onset Muscle Soreness and Recovery of Dynamic Performance Measures

    PubMed Central

    Pearcey, Gregory E. P.; Bradbury-Squires, David J.; Kawamoto, Jon-Erik; Drinkwater, Eric J.; Behm, David G.; Button, Duane C.

    2015-01-01

    Context: After an intense bout of exercise, foam rolling is thought to alleviate muscle fatigue and soreness (ie, delayed-onset muscle soreness [DOMS]) and improve muscular performance. Potentially, foam rolling may be an effective therapeutic modality to reduce DOMS while enhancing the recovery of muscular performance. Objective: To examine the effects of foam rolling as a recovery tool after an intense exercise protocol through assessment of pressure-pain threshold, sprint time, change-of-direction speed, power, and dynamic strength-endurance. Design: Controlled laboratory study. Setting: University laboratory. Patients or Other Participants: A total of 8 healthy, physically active males (age = 22.1 ± 2.5 years, height = 177.0 ± 7.5 cm, mass = 88.4 ± 11.4 kg) participated. Intervention(s): Participants performed 2 conditions, separated by 4 weeks, involving 10 sets of 10 repetitions of back squats at 60% of their 1-repetition maximum, followed by either no foam rolling or 20 minutes of foam rolling immediately, 24, and 48 hours postexercise. Main Outcome Measure(s): Pressure-pain threshold, sprint speed (30-m sprint time), power (broad-jump distance), change-of-direction speed (T-test), and dynamic strength-endurance. Results: Foam rolling substantially improved quadriceps muscle tenderness by a moderate to large amount in the days after fatigue (Cohen d range, 0.59 to 0.84). Substantial effects ranged from small to large in sprint time (Cohen d range, 0.68 to 0.77), power (Cohen d range, 0.48 to 0.87), and dynamic strength-endurance (Cohen d = 0.54). Conclusions: Foam rolling effectively reduced DOMS and associated decrements in most dynamic performance measures. PMID:25415413

  17. Effect of pressure on structure and NO sub X formation in CO-air diffusion flames

    NASA Technical Reports Server (NTRS)

    Maahs, H. G.; Miller, I. M.

    1979-01-01

    A study was made of nitric oxide formation in a laminar CO-air diffusion flame over a pressure range from 1 to 50 atm. The carbon monoxide (CO) issued from a 3.06 mm diameter port coaxially into a coflowing stream of air confined within a 20.5 mm diameter chimney. Nitric oxide concentrations from the flame were measured at two carbon monoxide (fuel) flow rates: 73 standard cubic/min and 146 sccm. Comparison of the present data with data in the literature for a methane-air diffusion flame shows that for flames of comparable flame height (8 to 10 mm) and pseudoequivalence ratio (0.162), the molar emission index of a CO-air flame is significantly greater than that of a methane-air flame.

  18. Detection of carbon dioxide leakage during injection in deep saline formations by pressure tomography

    NASA Astrophysics Data System (ADS)

    Hu, Linwei; Bayer, Peter; Brauchler, Ralf

    2016-07-01

    CO2 injected into storage formations may escape to the overlying permeable layers. Mixed-phase diffusivity, namely the ratio of hydraulic conductivity and specific storage of the phase mixture, declines with increasing CO2 saturation. Thus, it can be an indicator of CO2 leakage. In this study, we perform interference brine or CO2 injection tests in a synthetic model, including a storage reservoir, an above aquifer, and a caprock. Pressure transients derived from an observation well are utilized for a travel-time based inversion technique. Variations of diffusivity are resolved by inverting early travel time diagnostics, providing an insight of plume development. Results demonstrate that the evolution of CO2 leakage in the above aquifer can be inferred by interpreting and comparing the pressure observations, travel times, and diffusivity tomograms from different times. The extent of the plume in reservoir and upper aquifer are reconstructed by clustering the time-lapse data sets of the mixed-phase diffusivity, as the diffusivity cannot be exactly reproduced by the inversion. Furthermore, this approach can be used to address different leaky cases, especially for leakage occurring during the injection.

  19. Soot formation and temperature structure in small methane-oxygen diffusion flames at subcritical and supercritical pressures

    SciTech Connect

    Joo, Hyun I.; Guelder, Oemer L.

    2010-06-15

    An experimental study was conducted to examine the characteristics of laminar methane-oxygen diffusion flames up to 100 atmospheres. The influence of pressure on soot formation and on the structure of the temperature field was investigated over the pressure range of 10-90 atmospheres in a high-pressure combustion chamber using a non-intrusive, line-of-sight spectral soot emission diagnostic technique. Two distinct zones characterized the appearance of a methane and pure oxygen diffusion flame: an inner luminous zone similar to the methane-air diffusion flames, and an outer diffusion flame zone which is mostly blue. The flame height, marked by the visible soot radiation emission, was reduced by over 50% over the pressure range of 10-100 atmospheres. Between 10 and 40 atmospheres, the soot levels increased with increasing pressure; however, above 40 atmospheres the soot concentrations decreased with increasing pressure. (author)

  20. Soot Formation in Laminar Premixed Methane/Oxygen Flames at Atmospheric Pressure. Appendix H

    NASA Technical Reports Server (NTRS)

    Xu, F.; Lin, K.-C.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2001-01-01

    Flame structure and soot formation were studied within soot-containing laminar premixed methanefoxygen flames at atmospheric pressure. The following measurements were made: soot volume fractions by laser extinction, soot temperatures by multiline emission, gas temperatures (where soot was absent) by corrected fine-wire thermocouples, soot structure by thermophoretic sampling and transmission electron microscope (TEM), major gas species concentrations by sampling and gas chromatography, and gas velocities by laser velocimetry. Present measurements of gas species concentrations were in reasonably good agreement with earlier measurements due to Ramer et al. as well as predictions based on the detailed mechanisms of Frenklach and co-workers and Leung and Lindstedt; the predictions also suggest that H atom concentrations are in local thermodynamic equilibrium throughout the soot formation region. Using this information, it was found that measured soot surface growth rates could be correlated successfully by predictions based on the hydrogenabstraction/carbon-addition (HACA) mechanisms of both Frenklach and co-workers and Colket and Hall, extending an earlier assessment of these mechanisms for premixed ethylene/air flames to conditions having larger H/C ratios and acetylene concentrations. Measured primary soot particle nucleation rates were somewhat lower than the earlier observations for laminar premixed ethylene/air flames and were significantly lower than corresponding rates in laminar diffusion flames, for reasons that still must be explained.

  1. Soot Formation in Laminar Premixed Methane/Oxygen Flames at Atmospheric Pressure

    NASA Technical Reports Server (NTRS)

    Xu, F.; Lin, K.-C.; Faeth, G. M.

    1998-01-01

    Flame structure and soot formation were studied within soot-containing laminar premixed mc1hane/oxygen flames at atmospheric pressure. The following measurements were made: soot volume fractions by laser extinction, soot temperatures by multiline emission, gas temperatures (where soot was absent) by corrected fine-wire thermocouples, soot structure by thermophoretic sampling and transmission electron microscope (TEM), major gas species concentrations by sampling and gas chromatography, and gas velocities by laser velocimetry. Present measurements of gas species concentrations were in reasonably good agreement with earlier measurements due to Ramer et al. as well as predictions based on the detailed mechanisms of Frenklach and co-workers and Leung and Lindstedt: the predictions also suggest that H atom concentrations are in local thermodynamic equilibrium throughout the soot formation region. Using this information, it was found that measured soot surface growth rates could be correlated successfully by predictions based on the hydrogen-abstraction/carbon-addition (HACA) mechanisms of both Frenklach and co-workers and Colket and Hall, extending an earlier assessment of these mechanisms for premixed ethylene/air flames to conditions having larger H/C ratios and acetylene concentrations. Measured primary soot particle nucleation rates were somewhat lower than the earlier observations for laminar premixed ethylene/air flames and were significantly lower than corresponding rates in laminar diffusion flames. for reasons that still must be explained.

  2. Reducing Mechanical Formation Damage by Minimizing Interfacial Tension and Capillary Pressure in Tight Gas

    NASA Astrophysics Data System (ADS)

    Ahmed, Arshad; Talib Shuker, Muhannad; Rehman, Khalil; Bahrami, Hassan; Memon, Muhammad Khan

    2013-12-01

    Tight gas reservoirs incur problems and significant damage caused by low permeability during drilling, completion, stimulation and production. They require advanced improvement techniques to achieve flow gas at optimum rates. Water blocking damage (phase Trapping/retention of fluids) is a form of mechanical formation damage mechanism, which is caused by filtrate invasion in drilling operations mostly in fracturing. Water blocking has a noticeable impact on formation damage in gas reservoirs which tends to decrease relative permeability near the wellbore. Proper evaluation of damage and the factors which influence its severity is essential to optimize well productivity. Reliable data regarding interfacial tension between gas and water is required in order to minimize mechanical formation damage potential and to optimize gas production. This study was based on the laboratory experiments of interfacial tension by rising drop method between gas-brine, gas-condensate and gas-brine. The results showed gas condensate has low interfacial tension value 6 - 11 dynes/cm when compared to gas-brine and gas- diesel which were 44 - 58 dynes/cm and 14 - 19 dynes/cm respectively. In this way, the capillary pressure of brine-gas system was estimated as 0.488 psi, therefore diesel-gas system was noticed about 0.164 psi and 0.098 psi for condensate-gas system. A forecast model was used by using IFT values to predict the phase trapping which shows less severe phase trapping damage in case of condensate than diesel and brine. A reservoir simulation study was also carried out in order to better understand the effect of hysteresis on well productivity and flow efficiency affected due to water blocking damage in tight gas reservoirs.

  3. Heterogeneous Earth Accretion and Incomplete Metal-Silicate Reequilibration at High Pressure During Core Formation

    NASA Astrophysics Data System (ADS)

    Rubie, D. C.; Mann, U.; Frost, D. J.; Kegler, P.; Holzheid, A.; Palme, H.

    2007-12-01

    We present a new model of core formation, based on the partitioning of siderophile elements, that involves accreting the Earth through a series of collisions with smaller bodies that had already differentiated at low pressure. Each impact results in a magma ocean in which the core of the impactor reequilibrates with silicate liquid at high pressure before merging with the Earth's protocore. The oxygen contents of the chondritic compositions of the proto-Earth and impactors can be varied. The compositions of coexisting metal and silicate are determined through mass balance combined with partitioning equations for Ni, FeO, Si and other siderophile elements. The oxygen fugacity is fixed by the partitioning of FeO and is a function of P, T and bulk oxygen content. An important constraint for core formation is that core-mantle partition coefficients for Ni and Co must both converge to values of 23-28. Based on a recent study of the partitioning of Ni and Co over a wide P-T range (Kegler et al., EPSL, submitted) together with other published data, this constraint is not satisfied by a single- stage core formation model at any conditions because the partition coefficients converge at values that are much too low. In the present multi-stage model, the correct values can be reached if only part of each impactor core reequilibrates with silicate liquid in the magma ocean (as proposed by previous models based on Hf-W isotope studies). Physically, this would mean that impactor cores fail to emulsify completely as they sink through the magma ocean. Incorporating other elements (e.g. V and Cr) in the model requires, in addition, that the bulk composition of the impactors changes during accretion from reduced (FeO-poor) to oxidised FeO-rich). Then, with the resulting increase in fO2, incomplete reequilibration of the cores during the final 20-30% of Earth accretion is required to satisfy the Ni-Co constraint. In addition, this model enables the concentrations of O and Si in the

  4. Possible mechanism underlying high-pressure unfolding of proteins: formation of a short-period high-density hydration shell.

    PubMed

    Sumi, Tomonari; Sekino, Hideo

    2011-09-21

    Hydration effects on high-pressure unfolding of a hydrophobic polymer chain are investigated through a multiscale simulation based on density-functional theory. The results strongly suggest the following: a thermodynamic origin for high-pressure denaturation, i.e., the decrease in volume due to the unfolding can be explained by the formation of a short-period high-density hydration shell.

  5. The nursing rounds system: effect of patient's call light use, bed sores, fall and satisfaction level.

    PubMed

    Saleh, Bassem S; Nusair, Hussam; Al Zubadi, Nariman; Al Shloul, Shams; Saleh, Usama

    2011-06-01

    The nursing round system (NRS) means checking patients on an hourly basis during the A (0700-2200 h) shift and once every 2 h during the B (2200-0700 h) by the assigned nursing staff. The overall goal of this prospective study is to implement an NRS in a major rehabilitation centre-Sultan Bin Abdulaziz Humanitarian City-in the Riyadh area of the Kingdom of Saudi Arabia. The purposes of this study are to measure the effect of the NRS on: (i) the use of patient call light; (ii) the number of incidences of patients' fall; (iii) the number of incidences of hospital-acquired bed sores; and (iv) the level of patients' satisfaction. All patients hospitalized in the male stroke unit will be involved in this study. For the period of 8 weeks (17 December 2009-17 February 2010) All Nursing staff on the unit will record each call light and the patient's need. Implementation of the NRS would start on 18 February 2010 and last for 8 weeks, until 18 April 2010. Data collected throughout this period will be compared with data collected during the 8 weeks period immediately preceding the implementation of the NRS (17 December 2009-17 February 2010) in order to measure the impact of the call light use. The following information were collected on all subjects involved in the study: (i) the Demographic Information Form; (ii) authors' developed NRS Audit Form; (iii) Patient Call Light Audit Form; (iv) Patient Fall Audit Record; (v) Hospital-Acquired Bed Sores Audit Form; and (vi) hospital developed Patient Satisfaction Records. The findings suggested that a significant reduction on the use of call bell (P < 0.001), a significant reduction of fall incidence (P < 0.01) while pressure ulcer reduced by 50% before and after the implementation of NRS. Also, the implementation of NRS increased patient satisfaction by 7/5 (P < 0.05).

  6. Effect of Microcurrent Stimulation on Delayed-Onset Muscle Soreness: A Double-Blind Comparison

    PubMed Central

    Allen, Jennifer D.; Mattacola, Carl G.; Perrin, David H.

    1999-01-01

    Objective: To examine the efficacy of microcurrent electrical neuromuscular stimulation (MENS) treatment on pain and loss of range of motion (ROM) associated with delayed-onset muscle soreness (DOMS). Design and Setting: We assigned subjects to 1 of 2 groups. Group 1 received treatment with microcurrent stimulation (200 μA, 30 Hz, for 10 minutes, then 100 μA, 0.3 Hz, for 10 minutes) 24, 48, and 72 hours after DOMS induction. Group 2 served as a sham group and was treated using a machine altered by the manufacturer so that no current could flow through the electrodes. Subjects: DOMS was induced in the biceps brachii of the nondominant arm of 18 subjects (3 males, 15 females: age = 20.33 ± 2.3 years, ht = 170.81 ± 7.3 cm, wt = 69.61 ± 13.1 kg). Dominance was defined as the arm used by the subject to throw a ball. Measurements: Subjective pain and active elbow extension ROM were evaluated before and after treatment each day. Two methods were used to assess pain: constant pressure using a weighted Orthoplast sphere and full elbow extension to the limit of pain tolerance. Subjective pain was measured with a graphic rating scale and active elbow extension ROM using a standard, plastic, double-armed goniometer. Three repeated-measures ANOVAs (between-subjects variable was group, within- subjects variables were day and test) were used to assess ROM and pain scores for the 2 groups. Results: We found no significant difference in the measurement of subjective pain scores or elbow extension ROM when the MENS group was compared with the sham group. Conclusions: Our results indicate that the MENS treatment, within the parameters used for this experiment, was not effective in reducing the pain or loss of ROM associated with delayed-onset muscle soreness. PMID:16558582

  7. Acute sinusitis and sore throat in primary care.

    PubMed

    Del Mar, Chris

    2016-08-01

    Sore throat and acute sinusitis are not straightforward diagnoses. Trying to guess the responsible pathogen may not be the best approach. Being guided by empirical evidence may be more useful. It suggests some, but very few, benefits for antibiotics. This has to be balanced with some, but few, harms from antibiotics, including diarrhoea, rash and thrush. Prescribers should also be aware of the risk of antibiotic resistance for the individual, as well as for the population as a whole. GPs should explain the evidence for the benefits and the harms of antibiotics to patients within a shared decision-making framework.

  8. The anatomy of a star-forming galaxy: pressure-driven regulation of star formation in simulated galaxies

    NASA Astrophysics Data System (ADS)

    Benincasa, S. M.; Wadsley, J.; Couchman, H. M. P.; Keller, B. W.

    2016-11-01

    We explore the regulation of star formation in star-forming galaxies through a suite of high-resolution isolated galaxy simulations. We use the smoothed particle hydrodynamics code GASOLINE, including photoelectric heating and metal cooling, which produces a multi-phase interstellar medium (ISM). We show that representative star formation and feedback sub-grid models naturally lead to a weak, sub-linear dependence between the amount of star formation and changes to star formation parameters. We incorporate these sub-grid models into an equilibrium pressure-driven regulation framework. We show that the sub-linear scaling arises as a consequence of the non-linear relationship between scaleheight and the effective pressure generated by stellar feedback. Thus, simulated star formation regulation is sensitive to how well vertical structure in the ISM is resolved. Full galaxy discs experience density waves which drive locally time-dependent star formation. We develop a simple time-dependent, pressure-driven model that reproduces the response extremely well.

  9. Electrohydrodynamic pressure enhanced by free space charge for electrically induced structure formation with high aspect ratio.

    PubMed

    Tian, Hongmiao; Wang, Chunhui; Shao, Jinyou; Ding, Yucheng; Li, Xiangming

    2014-10-28

    Electrically induced structure formation (EISF) is an interesting and unique approach for generating a microstructured duplicate from a rheological polymer by a spatially modulated electric field induced by a patterned template. Most of the research on EISF have so far used various dielectric polymers (with an electrical conductivity smaller than 10(-10) S/m that can be considered a perfect dielectric), on which the electric field induces a Maxwell stress only due to the dipoles (or bounded charges) in the polymer molecules, leading to a structure with a small aspect ratio. This paper presents a different approach for improving the aspect ratio allowed in EISF by doping organic salt into the perfect dielectric polymer, i.e., turning the perfect dielectric into a leaky dielectric, considering the fact that the free space charges enriched in the leaky dielectric polymer can make an additional contribution to the Maxwell stress, i.e., electrohydrodynamic pressure, which is desirable for high aspect ratio structuring. Our numerical simulations and experimental tests have shown that a leaky dielectric polymer, with a small conductivity comparable to that of deionized water, can be much more effective at being electrohydrodynamically deformed into a high aspect ratio in comparison with a perfect dielectric polymer when both of them have roughly the same dielectric constant.

  10. Formation and characteristics of patterns in atmospheric-pressure radio-frequency dielectric barrier discharge plasma

    NASA Astrophysics Data System (ADS)

    Yang, Lizhen; Liu, Zhongwei; Mao, Zhiguo; Li, Sen; Chen, Qiang

    2017-01-01

    The patterns in radio-frequency dielectric barrier discharge (RF DBD) are studied at atmospheric pressure of argon (Ar) or helium (He) mixed with nitrogen (N2) gas. When a small amount of N2 is mixed with He or Ar gas, discharge patterns are formed. In a N2/He gas mixture, besides the filament discharge that forms patterns, a glow background discharge is also observed, whereas only the filament discharge forms patterns in a N2/Ar gas mixture. The resolution of the hexagonal pattern as a function of applied power and gas flow rate is then explored. On the basis of spatial-temporal images taken using an intensified charge-coupled device (ICCD), we find that there is no interleaving of two transient hexagon sublattices in N2/Ar or N2/He plasma in RF DBD patterns, which are totally different from those in which surface charges dominated in the mid-frequency DBD plasma. This supports our hypothesis that the bulk charges dominate the pattern formation in RF DBD.

  11. Cold sore susceptibility gene-1 genotypes affect the expression of herpes labialis in unrelated human subjects.

    PubMed

    Kriesel, John D; Bhatia, Amiteshwar; Thomas, Alun

    2014-01-01

    Our group has recently described a gene on human chromosome 21, the Cold Sore Susceptibility Gene-1 (CSSG-1, also known as C21orf91), which may confer susceptibility to frequent cold sores in humans. We present here a genotype-phenotype analysis of CSSG-1 in a new, unrelated human population. Seven hundred fifty-eight human subjects were enrolled in a case/control Cold Sore Study. CSSG-1 genotyping, herpes simplex virus 1 (HSV1) serotyping, demographic and phenotypic data was available from 622 analyzed subjects. Six major alleles (H1-H6) were tested for associations with each of the self-reported phenotypes. The statistical analysis was adjusted for age, sex and ethnicity. Genotype-phenotype associations were analyzed from 388 HSV1-seropositive subjects. There were significant CSSG-1 haplotype effects on annual cold sore outbreaks (P=0.006), lifetime cold sores (P=0.012) and perceived cold sore severity (P=0.012). There were relatively consistent trends toward protection from frequent and severe cold sores among those with the H3 or H5/6 haplotypes, whereas those with H1, H2, and H4 haplotypes tended to have more frequent and more severe episodes. Different alleles of the newly described gene CSSG-1 affect the expression of cold sore phenotypes in this new, unrelated human population, confirming the findings of the previous family-based study.

  12. 21 CFR 201.315 - Over-the-counter drugs for minor sore throats; suggested warning.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Over-the-counter drugs for minor sore throats... AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Specific Labeling Requirements for Specific Drug Products § 201.315 Over-the-counter drugs for minor sore throats; suggested warning. The Food...

  13. 21 CFR 201.315 - Over-the-counter drugs for minor sore throats; suggested warning.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Over-the-counter drugs for minor sore throats... AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Specific Labeling Requirements for Specific Drug Products § 201.315 Over-the-counter drugs for minor sore throats; suggested warning. The Food...

  14. Isomekes: A fundamental tool to determine the formation pressure for diamond-inclusion pairs

    NASA Astrophysics Data System (ADS)

    Alvaro, Matteo; Angel, Ross; Mazzucchelli, Mattia; Nestola, Fabrizio; Domeneghetti, Chiara

    2014-05-01

    Because diamond is almost chemically pure carbon and extremely chemically inert, the structure and chemistry of diamond reveals very little about its conditions of formation. Much of what is believed about the genesis and distribution of diamond in the Earth's mantle has therefore been deduced indirectly from the characterisation of its mineral inclusions. The possible depths of entrapment of an inclusion within a host phase (and hence the depth of growth of the host diamond) can be determined if (1) the final pressure of the inclusion can be measured, (2) the Equations of State (EoS) of the host and inclusion phases are known, and (3) the elastic interaction between the host and inclusion can be calculated without gross assumptions. Given knowledge of all three, an isomeke line in P-T space (from the Greek "equal" and "length", Adams et al. 1975) can be calculated. The isomeke defines the conditions at which the host and inclusion would have had the same P, T and volume, and thus represents possible entrapment conditions. The recent application (Nestola et al. 2011; Howell et al. 2012) of in-situ diffraction techniques to the measurement of entrapped inclusions provides accurate final inclusion pressures. We have reformulated the elasticity problem so that, unlike previous work, these calculations can be performed with any form of equation of state and thermal expansion, and are not restricted to linear elasticity or just invertible EoS. This alone has significant advantages in the precision of the calculated depths of formation. Numerical calculations have been performed with a new module of EoS routines (Angel et al. 2014) that has been added to the publicly-available CrysFML library. The question remains as to what uncertainties in calculated depths of formation arise from uncertainties in experimentally-determined EoS. We will present two geologically-relevant examples, for olivine and garnet in diamond. Our calculations show that there is still a clear need

  15. Diagenesis, compaction, and fluid chemistry modeling of a sandstone near a pressure seal: Lower Tuscaloosa Formation, Gulf Coast

    USGS Publications Warehouse

    Weedman, S.D.; Brantley, S.L.; Shiraki, R.; Poulson, S.R.

    1996-01-01

    Petrographic, isotopic, and fluid-inclusion evidence from normally and overpressured sandstones of the lower Tuscaloosa Formation (Upper Cretaceous) in the Gulf Coast documents quartz-overgrowth precipitation at 90??C or less, calcite cement precipitation at approximately 100?? and 135??C, and prismatic quartz cement precipitation at about 125??C. Textural evidence suggests that carbonate cement dissolution occurred before the second phases of calcite and quartz precipitation, and was followed by precipitation of grain-rimming chlorite and pore-filling kaolinite. Geochemical calculations demonstrate that present-day lower Tuscaloosa Formation water from 5500 m depth could either dissolve or precipitate calcite cements in model simulations of upward water flow. Calcite dissolution or precipitation depends on PCO2 variability with depth (i.e., whether there is one or two-phase flow) or on the rate of generation of CO2 with depth. Calculations suggest that 105-106 rock volumes of water are required to flow through the section to precipitate 1-10% calcite cement. Compaction analysis suggests that late-stage compaction occurred in normally pressured sandstones after dissolution of carbonate cements, but was hindered in overpressured sandstones despite the presence of high porosity. These results document the inhibition of compaction by overpressured fluids and constrain the timing of pressure seal formation. Modeling results demonstrate that the proposed paragenesis used to constrain timing of pressure seal formation is feasible, and that most of the cement diagenesis occurred before the pressure seal became effective as a permeability barrier.

  16. Homoeopathy for delayed onset muscle soreness: a randomised double blind placebo controlled trial.

    PubMed Central

    Vickers, A J; Fisher, P; Smith, C; Wyllie, S E; Lewith, G T

    1997-01-01

    OBJECTIVE: To pilot a model for determining whether a homoeopathic medicine is superior to placebo for delayed onset muscle soreness (DOMS). DESIGN: Randomised double blind placebo controlled trial. SETTING: Physiotherapy department of a homoeopathic hospital. SUBJECTS: Sixty eight healthy volunteers (average age 30; 41% men) undertook a 10 minute period of bench stepping carrying a small weight and were randomised to a homoeopathic medicine or placebo. OUTCOME MEASURES: Mean muscle soreness in the five day period after the exercise test, symptom free days, maximum soreness score, days to no soreness, days on medication. RESULTS: The difference between group means was 0.17 in favour of placebo with 95% confidence intervals +/- 0.50. Similar results were found for other outcome measures. CONCLUSION: The study did not find benefit of the homoeopathic remedy in DOMS. Bench stepping may not be an appropriate model to evaluate the effects of a treatment on DOMS because of wide variation between subject soreness scores. PMID:9429007

  17. Pressure-driven assembly of spherical nanoparticles and formation of 1D nanostructure arrays.

    SciTech Connect

    Wu, Huimeng

    2010-08-01

    External pressure was used to engineer nanoparticle assembly. Reversible manipulation of the unit-cell dimensions of a 3D ordered nanoparticle array under a hydrostatic pressure field enabled the fine-tuning of the interparticle distance. Under a uniaxial pressure field, nanoparticles were forced to contact and coalesce into nanorods or nanowires and ordered ultrahigh-density arrays (see picture; small arrows denote pressure).

  18. The effects of game and training loads on perceptual responses of muscle soreness in Australian football.

    PubMed

    Montgomery, Paul G; Hopkins, Will G

    2013-05-01

    Australian Football is an intense team sport played over ~120 min on a weekly basis. To determine the effects of game and training load on muscle soreness and the time frame of soreness dissipation, 64 elite Australian Football players (age 23.8 ± 1.8 y, height 183.9 ± 3.8 cm, weight 83.2 ± 5.0 kg; mean ± SD) recorded perceptions of muscle soreness, game intensity, and training intensity on scales of 1-10 on most mornings for up to 3 competition seasons. Playing and training times were also recorded in minutes. Data were analyzed with a mixed linear model, and magnitudes of effects on soreness were evaluated by standardization. All effects had acceptably low uncertainty. Game and training-session loads were 790 ± 182 and 229 ± 98 intensity-minutes (mean ± SD), respectively. General muscle soreness was 4.6 ± 1.1 units on d 1 postgame and fell to 1.9 ± 1.0 by d 6. There was a small increase in general muscle soreness (0.22 ± 0.07-0.50 ± 0.13 units) in the 3 d after high-load games relative to low-load games. Other soreness responses showed similar timelines and magnitudes of change. Training sessions made only small contributions to soreness over the 3 d after each session. Practitioners should be aware of these responses when planning weekly training and recovery programs, as it appears that game-related soreness dissipates after 3 d regardless of game load and increased training loads in the following week produce only small increases in soreness.

  19. Soot volume fraction measurement in low-pressure methane flames by combining laser-induced incandescence and cavity ring-down spectroscopy: Effect of pressure on soot formation

    SciTech Connect

    Desgroux, P.; Mercier, X.; Lefort, B.; Lemaire, R.; Therssen, E.; Pauwels, J.F.

    2008-10-15

    Soot volume fraction (f{sub v}) profiles are recorded in low-pressure methane/oxygen/nitrogen flat flames using laser-induced incandescence (LII). Experiments are performed from 20 to 28 kPa in flames having the same equivalence ratio (2.32). Calibration is performed by cavity ring-down spectroscopy (CRDS) and indicates a very weak soot volume fraction (0.066 ppb at 21.33 kPa and 0.8 ppb at 26.66 kPa in the burnt gases). Soot volume fraction is found to increase continuously after a given distance above the burner (HAB) and tends to level off in the burnt gases. The reaction time resolution available in low-pressure flames makes it possible to examine the early steps of soot formation. The variation of the LII signal with laser energy before the LII ''plateau'' region is much weaker at the beginning of soot formation than after a given reaction time. The LII time decays are nearly constant within the first millimetres, whereas an increase in the decay, correlated with the growth of the primary soot particle, is observed later. The growth of soot volume fraction is then analysed by considering the variation of the derivative function df{sub v}/dt with f{sub v}. Three regimes having respectively a positive slope, a constant slope, and a negative slope are observed and are interpreted with respect to the soot inception process. Finally, a very important sensitivity of f{sub v} with pressure P (at 30 mm HAB) is observed, leading to a power law, f{sub v}=KP{sup 11}, confirmed by extinction measurements (by CRDS). The observed dependence of f{sub v} with pressure could be a result of the prominence of the early soot inception process in the investigated low-pressure flames. (author)

  20. Soot Formation in Laminar Premixed Ethylene/Air Flames at Atmospheric Pressure. Appendix G

    NASA Technical Reports Server (NTRS)

    Xu, F.; Sunderland, P. B.; Faeth, G. M.; Urban, D. L. (Technical Monitor)

    2001-01-01

    Soot formation was studied within laminar premixed ethylene/air flames (C/O ratios of 0.78-0.98) stabilized on a flat-flame burner operating at atmospheric pressure. Measurements included soot volume fractions by both laser extinction and gravimetric methods, temperatures by multiline emission, soot structure by thermophoretic sampling and transmission electron microscopy, major gas species concentrations by sampling and gas chromatography, concentrations of condensable hydrocarbons by gravimetric sampling. and velocities by laser velocimetry. These data were used to find soot surface growth rates and primary soot particle nucleation rates along the axes of the flames. Present measurements of soot surface growth rates were correlated successfully by predictions based on typical hydrogen-abstraction/carbon-addition (HACA) mechanisms of Frenklach and co-workers and Colket and Hall. These results suavest that reduced soot surface growth rates with increasing residence time seen in the present and other similar flames were mainly caused by reduced rates of surface activation due to reduced H atom concentrations as temperatures decrease as a result of radiative heat losses. Primary soot particle nucleation rates exhibited variations with temperature and acetylene concentrations that were similar to recent observations for diffusion flames; however, nucleation rates in the premixed flames were significantly lower than in, the diffusion flames for reasons that still must be explained. Finally, predictions of yields of major gas species based on mechanisms from both Frenklach and co-workers and Leung and Lindstedt were in good agreement with present measurements and suggest that H atom concentrations (relevant to HACA mechanisms) approximate estimates based on local thermodynamic equilibrium in the present flames.

  1. High positive end-expiratory pressure: only a dam against oedema formation?

    PubMed Central

    2013-01-01

    Introduction Healthy piglets ventilated with no positive end-expiratory pressure (PEEP) and with tidal volume (VT) close to inspiratory capacity (IC) develop fatal pulmonary oedema within 36 h. In contrast, those ventilated with high PEEP and low VT, resulting in the same volume of gas inflated (close to IC), do not. If the real threat to the blood-gas barrier is lung overinflation, then a similar damage will occur with the two settings. If PEEP only hydrostatically counteracts fluid filtration, then its removal will lead to oedema formation, thus revealing the deleterious effects of overinflation. Methods Following baseline lung computed tomography (CT), five healthy piglets were ventilated with high PEEP (volume of gas around 75% of IC) and low VT (25% of IC) for 36 h. PEEP was then suddenly zeroed and low VT was maintained for 18 h. Oedema was diagnosed if final lung weight (measured on a balance following autopsy) exceeded the initial one (CT). Results Animals were ventilated with PEEP 18 ± 1 cmH2O (volume of gas 875 ± 178 ml, 89 ± 7% of IC) and VT 213 ± 10 ml (22 ± 5% of IC) for the first 36 h, and with no PEEP and VT 213 ± 10 ml for the last 18 h. On average, final lung weight was not higher, and actually it was even lower, than the initial one (284 ± 62 vs. 347 ± 36 g; P = 0.01). Conclusions High PEEP (and low VT) do not merely impede fluid extravasation but rather preserve the integrity of the blood-gas barrier in healthy lungs. PMID:23844622

  2. Methane hydrate synthesis from ice: Influence of pressurization and ethanol on optimizing formation rates and hydrate yield

    USGS Publications Warehouse

    Chen, Po-Chun.; Huang, Wuu-Liang; Stern, Laura A.

    2010-01-01

    Polycrystalline methane gas hydrate (MGH) was synthesized using an ice-seeding method to investigate the influence of pressurization and ethanol on the hydrate formation rate and gas yield of the resulting samples. When the reactor is pressurized with CH4 gas without external heating, methane hydrate can be formed from ice grains with yields up to 25% under otherwise static conditions. The rapid temperature rise caused by pressurization partially melts the granular ice, which reacts with methane to form hydrate rinds around the ice grains. The heat generated by the exothermic reaction of methane hydrate formation buffers the sample temperature near the melting point of ice for enough time to allow for continuous hydrate growth at high rates. Surprisingly, faster rates and higher yields of methane hydrate were found in runs with lower initial temperatures, slower rates of pressurization, higher porosity of the granular ice samples, or mixtures with sediments. The addition of ethanol also dramatically enhanced the formation of polycrystalline MGH. This study demonstrates that polycrystalline MGH with varied physical properties suitable for different laboratory tests can be manufactured by controlling synthesis procedures or parameters. Subsequent dissociation experiments using a gas collection apparatus and flowmeter confirmed high methane saturation (CH 4·2O, with n = 5.82 ± 0.03) in the MGH. Dissociation rates of the various samples synthesized at diverse conditions may be fitted to different rate laws, including zero and first order.

  3. In Situ Formation and Evolution of Gas Hydrates in Water-in-Oil Emulsions Using Pressure Rheometry

    NASA Astrophysics Data System (ADS)

    Rensing, P. J.; Liberatore, M. W.; Tonmukayakul, N.; Koh, C. A.; Sloan, E. D.

    2008-07-01

    In oil and gas production and transportation a major concern is the formation of gas hydrates (crystalline gas-water inclusion compounds that are stable at high pressures and low temperatures). Gas hydrates have a tenacious ability to plug pipelines, and may lead to unscheduled shut downs. The successful operation of pipeline transport with gas hydrates particles will depend on the ability to control gas hydrate agglomerations and depositions. Gas hydrates can be thermodynamically inhibited but this is proving cost ineffective and environmentally unfriendly. For this reason the oil/gas industry is moving to hydrate management rather than traditional methods of thermodynamic inhibition. One intriguing possibility would be to convert the water in the pipelines to non-agglomerating gas hydrates and then flow the slurry. However, this cannot be reliably achieved until basic understanding of hydrate slurry rheology is gained. To develop this fundamental understanding, in situ pressurized gas hydrate formation and rheological measurements from a water-in-oil emulsion have been conducted. In this work, small amplitude oscillatory and steady shear techniques have been used to characterize the rheological properties of these systems. The results demonstrate that hydrate formation can be detected in steady shear and oscillatory measurements, where a large viscosity (and elastic modulus) increase coincides with hydrate formation. Since temperature and pressure affect the thermodynamic stability of hydrates these are particular key variables that need to be tuned for this system.

  4. Delayed onset muscle soreness : treatment strategies and performance factors.

    PubMed

    Cheung, Karoline; Hume, Patria; Maxwell, Linda

    2003-01-01

    Delayed onset muscle soreness (DOMS) is a familiar experience for the elite or novice athlete. Symptoms can range from muscle tenderness to severe debilitating pain. The mechanisms, treatment strategies, and impact on athletic performance remain uncertain, despite the high incidence of DOMS. DOMS is most prevalent at the beginning of the sporting season when athletes are returning to training following a period of reduced activity. DOMS is also common when athletes are first introduced to certain types of activities regardless of the time of year. Eccentric activities induce micro-injury at a greater frequency and severity than other types of muscle actions. The intensity and duration of exercise are also important factors in DOMS onset. Up to six hypothesised theories have been proposed for the mechanism of DOMS, namely: lactic acid, muscle spasm, connective tissue damage, muscle damage, inflammation and the enzyme efflux theories. However, an integration of two or more theories is likely to explain muscle soreness. DOMS can affect athletic performance by causing a reduction in joint range of motion, shock attenuation and peak torque. Alterations in muscle sequencing and recruitment patterns may also occur, causing unaccustomed stress to be placed on muscle ligaments and tendons. These compensatory mechanisms may increase the risk of further injury if a premature return to sport is attempted.A number of treatment strategies have been introduced to help alleviate the severity of DOMS and to restore the maximal function of the muscles as rapidly as possible. Nonsteroidal anti-inflammatory drugs have demonstrated dosage-dependent effects that may also be influenced by the time of administration. Similarly, massage has shown varying results that may be attributed to the time of massage application and the type of massage technique used. Cryotherapy, stretching, homeopathy, ultrasound and electrical current modalities have demonstrated no effect on the alleviation of

  5. Cenosphere formation from heavy fuel oil: a numerical analysis accounting for the balance between porous shells and internal pressure

    NASA Astrophysics Data System (ADS)

    Reddy, Vanteru M.; Rahman, Mustafa M.; Gandi, Appala N.; Elbaz, Ayman M.; Schrecengost, Robert A.; Roberts, William L.

    2016-01-01

    Heavy fuel oil (HFO) as a fuel in industrial and power generation plants ensures the availability of energy at economy. Coke and cenosphere emissions from HFO combustion need to be controlled by particulate control equipment such as electrostatic precipitators, and collection effectiveness is impacted by the properties of these particulates. The cenosphere formation is a function of HFO composition, which varies depending on the source of the HFO. Numerical modelling of the cenosphere formation mechanism presented in this paper is an economical method of characterising cenosphere formation potential for HFO in comparison to experimental analysis of individual HFO samples, leading to better control and collection. In the present work, a novel numerical model is developed for understanding the global cenosphere formation mechanism. The critical diameter of the cenosphere is modelled based on the balance between two pressures developed in an HFO droplet. First is the pressure (Prpf) developed at the interface of the liquid surface and the inner surface of the accumulated coke due to the flow restriction of volatile components from the interior of the droplet. Second is the pressure due to the outer shell strength (PrC) gained from van der Walls energy of the coke layers and surface energy. In this present study it is considered that when PrC ≥ Prpf the outer shell starts to harden. The internal motion in the shell layer ceases and the outer diameter (DSOut) of the shell is then fixed. The entire process of cenosphere formation in this study is analysed in three phases: regression, shell formation and hardening, and post shell hardening. Variations in pressures during shell formation are analysed. Shell (cenosphere) dimensions are evaluated at the completion of droplet evaporation. The rate of fuel evaporation, rate of coke formation and coke accumulation are analysed. The model predicts shell outer diameters of 650, 860 and 1040 µm, and inner diameters are 360, 410

  6. Ultrasound Findings of Delayed-Onset Muscle Soreness.

    PubMed

    Longo, Victor; Jacobson, Jon A; Fessell, David P; Mautner, Kenneth

    2016-11-01

    The purpose of this series was to retrospectively characterize the ultrasound findings of delayed-onset muscle soreness (DOMS). The Institutional Review Board approved our study, and informed consent was waived. A retrospective search of radiology reports using the key phrase "delayed-onset muscle soreness" and key word "DOMS" from 2001 to 2015 and teaching files was completed to identify cases. The sonograms were reviewed by 3 fellowship-trained musculoskeletal radiologists by consensus. Sonograms were retrospectively characterized with respect to echogenicity (hypoechoic, isoechoic, or hyperechoic), distribution of muscle involvement, and intramuscular pattern (focal versus diffuse and well defined versus poorly defined). Images were also reviewed for muscle enlargement, fluid collection, muscle fiber disruption, and increased flow on color or power Doppler imaging. There were a total of 6 patients identified (5 male and 1 female). The average age was 22 years (range, 7-44 years). Of the 6 patients, there were a total of 11 affected muscles in 7 extremities (1 bilateral case). The involved muscles were in the upper extremity: triceps brachii in 27% (3 of 11), biceps brachii in 18% (2 of 11), brachialis in 18% (2 of 11), brachioradialis in 18% (2 of 11), infraspinatus in 9% (1 of 11), and deltoid in 9% (1 of 11). On ultrasound imaging, the abnormal muscle was hyperechoic in 100% (11 of 11), well defined in 73% (8 of 11), poorly defined in 27% (3 of 11), diffuse in 73% (8 of 11), and focal in 27% (3 of 11). Increased muscle size was found in 82% (9 of 11) and minimal hyperemia in 87.5% (7 of 8). The ultrasound findings of DOMS include hyperechoic involvement of an upper extremity muscle, most commonly appearing well defined and diffuse with increased muscle size and minimal hyperemia.

  7. Moist Heat or Dry Heat for Delayed Onset Muscle Soreness

    PubMed Central

    Petrofsky, Jerrold; Berk, Lee; Bains, Gurinder; Khowailed, Iman Akef; Hui, Timothy; Granado, Michael; Laymon, Mike; Lee, Haneul

    2013-01-01

    Background Heat is commonly used in physical therapy following exercise induced delayed onset muscle soreness (DOMS). Most heat modalities used in a clinical setting for DOMS are only applied for 5 to 20 minutes. This minimal heat exposure causes little, if any, change in deep tissue temperature. For this reason, long duration dry chemical heat packs are used at home to slowly and safely warm tissue and reduce potential heat damage while reducing pain associated from DOMS. Clinically, it has been shown that moist heat penetrates deep tissue faster than dry heat. Therefore, in home use chemical moist heat may be more efficacious than dry heat to provide pain relief and reduce tissue damage following exercise DOMS. However, chemical moist heat only lasts for 2 hours compared to the 8 hours duration of chemical dry heat packs. The purpose of this study was to compare the beneficial effect of dry heat versus moist heat on 100 young subjects after exercise induce DOMS. Methods One hundred subjects exercised for 15 minutes accomplishing squats. Before and for 3 days after, strength, muscle soreness, tissue resistance, and the force to passively move the knee were recorded. Heat and moist heat were applied in different groups either immediately after exercise or 24 hours later. Results The research results of this study showed that immediate application of heat, either dry (8 hours application) or moist (2 hours application), had a similar preservation of quadriceps muscle strength and muscle activity. Results also revealed that the greatest pain reduction was shown after immediate application of moist heat. Never the less, immediate application of dry heat had a similar effect but to a lesser extent. Conclusion It should be noted that moist heat had not only similar benefits of dry heat but in some cases enhanced benefits, and with only 25% of the time of application of the dry heat. PMID:24171053

  8. Interpretation of in-situ pressure and flow measurements of the Salado Formation at the Waste Isolation Pilot Plant

    SciTech Connect

    Howarth, S.M.; Peterson, E.W.; Lagus, P.L.; Lie, K.; Finley, S.J.; Nowak, E.J.

    1991-01-01

    This paper describes preliminary interpretation of in-situ pressure and flow measurements of the Salado Formation at the Waste Isolation Pilot Plant (WIPP). The WIPP facility is located 660 m underground in the Salado, a bedded salt deposit. Shut-in pressure tests were conducted prior to, and subsequent to, the mining of a circular drift in order to evaluate excavation effects on pore pressure, permeability, and host rock heterogeneity. Borehole deformation was measured during these tests and used to correct for changes in the test region volume due to salt creep effects. Preliminary pre-excavation results indicate that the flow properties of this layered host rock are heterogeneous. Resulting pore pressures range from 1 to 14 MPa and permeabilities range from below measurable to about 1 nanodarcy. Normalized borehole diameter change rates were between {minus}4 and 63 microstrains/day. Shut-in pressures and borehole diameters in all test boreholes were affected by the excavation of Room Q coincident with the advances of the boring machine. Preliminary results from post-excavation test results show decreased pore pressures compared to pre-excavation values.

  9. Biogenic amines formation in high-pressure processed pike flesh (Esox lucius) during storage.

    PubMed

    Křížek, Martin; Matějková, Kateřina; Vácha, František; Dadáková, Eva

    2014-05-15

    The effects of vacuum packaging followed by high pressure processing on the shelf-life of fillets of pike (Esox lucius) were examined. Samples were pressure-treated at 300 and 500 MPa and stored at 3.5 and 12 °C for up to 70 days. The content of eight biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine, tryptamine and phenylethylamine) were determined. Putrescine showed very good correspondence with the level of applied pressure and organoleptic properties. Polyamines spermidine and spermine did not show statistically significant changes with the level of applied pressure and the time of storage. Increased cadaverine and tyramine contents were found in samples with good sensory signs, stored for longer time and/or kept at 12 °C, thus indicating the loss of freshness. Tryptamine and phenylethylamine were not detected in pressure-treated samples kept at 3.5 °C. Histamine was not detected in samples of good quality.

  10. "Real-time" core formation experiments using X-ray tomography at high pressure and temperature

    NASA Astrophysics Data System (ADS)

    Watson, H. C.; Anzures, B.; Yu, T.; Wang, Y.

    2015-12-01

    The process of differentiation is a defining moment in a planet's history. Direct observation of this process at work is impossible in our solar system because it was complete within the first few tens of millions of years. Geochemical and geophysical evidence points to magma ocean scenarios to explain differentiation of large planets such as Earth. Smaller planets and planetesimals likely never achieved the high temperatures necessary for wide scale melting. In these smaller bodies, silicates may have only partially melted, or not melted at all. Furthermore, isotopic signatures in meteorites suggest that some planetesimals differentiated within just a few million years. Achieving efficient core segregation on this rapid timescale is difficult, particularly in a solid or semi-solid silicate matrix. Direct measurements of metallic melt migration velocities have been difficult due to experimental limitations and most previous work has relied on geometric models based on 2-D observations in quenched samples. We have employed a relatively new technique of in-situ, high pressure, high temperature, X-ray micro-tomography coupled with 3-D numerical simulations to evaluate the efficiency of melt percolation in metal/silicate systems. From this, we can place constraints on the timing of core formation in early solar system bodies. Mixtures of olivine and KLB-1 peridotite and up to 12 vol% FeS were pre-synthesized to achieve an initial equilibrium microstructure of silicate and sulfide. The samples were then were then pressed again to ~2GPa, and heated to ~1300°C to collect X-ray tomography images as the partially molten samples were undergoing shear deformation. The reconstructed 3-D images of melt distribution were used as the input for lattice Boltzmann simulations of fluid flow through the melt network and calculations of permeability and melt migration velocity. Our in-situ x-ray tomography results are complemented by traditional 2-D image analysis and high

  11. A custom-made silicon mold for pressure therapy to ear keloids.

    PubMed

    Yigit, B; Yazar, M; Alyanak, A; Guven, E

    2009-11-01

    Keloids are raised reddish nodules that develop at the site of an injury. They are characterized histologically by an abundance of fibroblasts, thick collagen bundles, and ground substance. Auricular keloid formation is a known complication of ear piercing. Many types of treatments have been described for auricular keloids.Pressure therapy in combination with surgery, corticosteroid injection, or both is widely used to manage and prevent hypertrophic scarring. Many pressure devices and procedures have been developed. However, all of them are designed for the earlobe region. If a keloid grows in the posterior auricular region, none of the devices described in the literature will be effective. The authors developed a custom-made silicon ear mold that covers whole ear. With this mold, pressure can be applied homogeneously to the lobule and cartilaginous region, which the other devices described in the literature cannot affect. The preparation technique includes making the negative cast mold of the patient's ear, creating the positive cast mold from the negative cast mold, and forming the negative silicon mold from the positive cast. After all the processes, a silicon sheet has been designed according to the region needing to be pressurized. The designed silicon sheet is applied to the region, followed by placement of the silicon mold. A simple tennis head band can be used to stabilize the silicon cast. If the keloid extends to the posterior auricular region, pressurizing with clips or other devices described previously will be difficult. Application of pressure to the cartilaginous auricle needs custom-made devices. At this point, a pressure sore caused by a device applied to the ear is the most important problem. To prevent the ear from developing a pressure sore, the device should press to whole area homogeneously. For this reason, the device applied for pressure therapy to the ear must be custom made.

  12. On Porosity Formation in Metal Matrix Composites Made with Dual-Scale Fiber Reinforcements Using Pressure Infiltration Process

    NASA Astrophysics Data System (ADS)

    Etemadi, Reihaneh; Pillai, Krishna M.; Rohatgi, Pradeep K.; Hamidi, Sajad Ahmad

    2015-05-01

    This is the first such study on porosity formation phenomena observed in dual-scale fiber preforms during the synthesis of metal matrix composites (MMCs) using the gas pressure infiltration process. In this paper, different mechanisms of porosity formation during pressure infiltration of Al-Si alloys into Nextel™ 3D-woven ceramic fabric reinforcements (a dual-porosity or dual-scale porous medium) are studied. The effect of processing conditions on porosity content of the ceramic fabric infiltrated by the alloys through the gas PIP (PIP stands for "Pressure Infiltration Process" in which liquid metal is injected under pressure into a mold packed with reinforcing fibers.) is investigated. Relative density (RD), defined as the ratio of the actual MMC density and the density obtained at ideal 100 pct saturation of the preform, was used to quantify the overall porosity. Increasing the infiltration temperature led to an increase in RD due to reduced viscosity of liquid metal and enhanced wettability leading to improved feedability of the liquid metal. Similarly, increasing the infiltration pressure led to enhanced penetration of fiber tows and resulted in higher RD and reduced porosity. For the first time, the modified Capillary number ( Ca*), which is found to predict formation of porosity in polymer matrix composites quite well, is employed to study porosity in MMCs made using PIP. It is observed that in the high Ca* regime which is common in PIP, the overall porosity shows a strong downward trend with increasing Ca*. In addition, the effect of matrix shrinkage on porosity content of the samples is studied through using a zero-shrinkage Al-Si alloy as the matrix; usage of this alloy as the matrix led to a reduction in porosity content.

  13. 21 CFR 880.5550 - Alternating pressure air flotation mattress.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... body pressure. The device is used to prevent and treat decubitus ulcers (bed sores). (b) Classification... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alternating pressure air flotation mattress. 880... Personal Use Therapeutic Devices § 880.5550 Alternating pressure air flotation mattress. (a)...

  14. Double negative pressure for seroma treatment in trocanteric area.

    PubMed

    Calderon, Wilfredo L; Llanos, Sergio; Leniz, Patricio; Danilla, Stefan; Vielma, Rodrigo; Calderon, Daniel

    2009-12-01

    We report the use of topic negative pressure for seromas resulting from mobilization of tensor fascia lata miocutaneous flap in the trochanteric areas for pressure sores. In 5 consecutive patients we successfully treated seroma with the use of external and internal topic subatmospheric pressure.

  15. Influence of ambient pressure on the hole formation in laser deep drilling

    NASA Astrophysics Data System (ADS)

    Döring, S.; Richter, S.; Heisler, F.; Ullsperger, T.; Tünnermann, A.; Nolte, S.

    2013-09-01

    We investigate the temporal evolution of the hole depth and shape for percussion drilling at different ambient pressure conditions. Deep drilling is performed in silicon as target material by ultrashort laser pulses at 1030 nm and a duration of 8 ps. Simultaneously, the backlit silhouette of the hole is imaged perpendicular to the drilling direction. While typical process phases like depth development and shape evolution are very similar for atmospheric pressure down to vacuum conditions (10-2 mbar), the ablation rate in the initial process phase is significantly increased for reduced pressure. The number of pulses till the stop of the drilling process also increases by a pressure reduction and exceeds drilling at atmospheric conditions by two orders of magnitude for a pressure of ca. 10-2 mbar. Accordingly, the maximum achievable hole depth is more than doubled. We attribute this behavior to an enlarged mean free path for ablation products at reduced pressure and therefore lower or no deposition of particles inside the hole capillary under vacuum conditions while debris fills the hole already after a few thousand pulses at atmospheric pressure. This is supported by scanning electron cross section images of the holes.

  16. The effect of ram-pressure stripping and starvation on the star formation properties of cluster galaxies

    NASA Astrophysics Data System (ADS)

    Boselli, A.; Boissier, S.; Cortese, L.; Gavazzi, G.

    2009-12-01

    We have combined UV to radio centimetric observations of resolved galaxies in the Virgo cluster with multizone, chemo-spectrophotometric models of galaxy evolution especially tailored to take into account the effects of the cluster environment (ram pressure stripping and starvation). This exercise has shown that anemic spirals with truncated radial profiles of the gas component and of the young stellar populations, typical in rich clusters of galaxies, have been perturbed by a recent (˜100 Myr) ram pressure stripping event induced by their interaction with the cluster intergalactic medium. Starvation is not able to reproduce the observed truncated radial profiles. Both ram pressure and starvation induce a decrease of the stellar surface brightness of the perturbed disc, and thus can hardly be invoked to explain the formation of lenticular galaxies inhabiting rich clusters, which are characterised by higher surface brightnesses than early type spirals of similar luminosity. In dwarfs the ram pressure stripping event is so efficient to totally remove their gas thus stopping on short time scales (<2 Gyr) their star formation activity. Low luminosity star forming discs can be transformed in dE galaxies.

  17. Buffer arrangement with back flushing of a quartz pressure transducer in a formation testing device

    SciTech Connect

    Gilbert, G.J.

    1993-08-03

    For use with a pressure sensor located in a sensor chamber in a sonde wherein the pressure sensor forms measurements of ambient pressure, an apparatus is described which comprises an elongate flow path from said sensor chamber to a source of fluid to be measured and wherein said fluid flow path comprises a passage within the threads of first and second threaded sonde components threaded together to define a helical flow path, wherein said helical flow path comprises first and second helical flow path segments serially connected.

  18. Durability of SRP Waste Glass - Effects of Pressure and Formation of Surface Layers

    SciTech Connect

    Wicks, G.G.

    2001-10-17

    This report discusses results of an assessment of pressure at anticipated storage temperature on the chemical durability of Savannah River Plant waste glass. Surface interactions were also examined and corrosion mechanisms discussed.

  19. Barometric pressure transient testing applications at the Nevada Test Site: formation permeability analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1984-12-01

    The report evaluates previous investigations of the gas permeability of the rock surrounding emplacement holes at the Nevada Test Site. The discussion sets the framework from which the present uncertainty in gas permeability can be overcome. The usefulness of the barometric pressure testing method has been established. Flow models were used to evaluate barometric pressure transients taken at NTS holes U2fe, U19ac and U20ai. 31 refs., 103 figs., 18 tabs. (ACR)

  20. Active CO2 Reservoir Management: A Strategy for Controlling Pressure, CO2 and Brine Migration in Saline-Formation CCS

    NASA Astrophysics Data System (ADS)

    Buscheck, T. A.; Sun, Y.; Hao, Y.; Court, B.; Celia, M. A.; Wolery, T.; Tompson, A. F.; Aines, R. D.; Friedmann, J.

    2010-12-01

    CO2 capture and sequestration (CCS) in deep geological formations is regarded as a promising means of lowering the amount of CO2 emitted to the atmosphere and thereby mitigate global warming. The most promising systems for CCS are depleted oil reservoirs, particularly those suited to CO2-based Enhanced Oil Recovery (CCS-EOR), and deep saline formations, both of which are well separated from the atmosphere. For conventional, industrial-scale, saline-formation CCS, pressure buildup can have a limiting effect on CO2 storage capacity. To address this concern, we analyze Active CO2 Reservoir Management (ACRM), which combines brine extraction and residual-brine reinjection with CO2 injection, comparing it with conventional saline-formation CCS. We investigate the influence of brine extraction on pressure response and CO2 and brine migration using the NUFT code. By extracting brine from the lower portion of the storage formation, from locations progressively further from the center of injection, we can counteract buoyancy that drives CO2 to the top of the formation, which is useful in dipping formations. Using “push-pull” manipulation of the CO2 plume, we expose less of the caprock seal to CO2 and more of the storage formation to CO2, with more of the formation utilized for trapping mechanisms. Plume manipulation can also counteract the influence of heterogeneity. We consider the impact of extraction ratio, defined as net extracted brine volume (extraction minus reinjection) divided by injected CO2 volume. Pressure buildup is reduced with increasing extraction ratio, which reduces CO2 and brine migration, increases CO2 storage capacity, and reduces other risks, such as leakage up abandoned wells, caprock fracturing, fault activation, and induced seismicity. For a 100-yr injection period, a 10-yr delay in brine extraction does not diminish the magnitude of pressure reduction. Moreover, it is possible to achieve pressure management with just a few brine-extraction wells

  1. Polymerization of cyanoacetylene under pressure: Formation of carbon nitride polymers and bulk structures

    NASA Astrophysics Data System (ADS)

    Khazaei, Mohammad; Liang, Yunye; Venkataramanan, Natarajan S.; Kawazoe, Yoshiyuki

    2012-02-01

    High-pressure phase transitions of polar and nonpolar molecular structures of cyanoacetylene (HC3N) are studied by using first-principles simulations at constant pressure. In both polar and nonpolar crystals, at pressure ˜20 GPa, the cyanoacetylene molecules are interconnected together and form polyacrylonitrile (PA) polymers. At pressure ˜30 GPa, PA polymers are transformed to polymers with fused pyridine rings (FPR's). The individual geometrical structures of PA and FPR polymers obtained from polar and nonpolar molecular crystals of cyanoacetylene are identical, but their stacking is different. At pressures above 40 GPa, the FPR polymers are interconnected together and new three-dimensional (3D) carbon nitride systems are formed. At ambient pressure, the long-length PA and FPR polymers are metallic, and the created 3D structures are an insulator with energy band gaps around 2.85 eV. The electron transport characteristics of FPR polymers with different lengths are investigated at finite biases by using the nonequilibrium Green's function technique combined with density functional theory (DFT) by connecting the polymers to gold electrodes. The results show that FPR polymers have negative differential resistance behavior. Our time-dependent DFT calculations reveal that FPR polymers can absorb light in the visible region. From our results, it is expected that the FPR polymers will be a good material for optoelectronic applications.

  2. Abiotic Formation of Valine Peptides Under Conditions of High Temperature and High Pressure

    NASA Astrophysics Data System (ADS)

    Furukawa, Yoshihiro; Otake, Tsubasa; Ishiguro, Takato; Nakazawa, Hiromoto; Kakegawa, Takeshi

    2012-12-01

    We investigated the oligomerization of solid valine and the stabilities of valine and valine peptides under conditions of high temperature (150-200 °C) and high pressure (50-150 MPa). Experiments were performed under non-aqueous condition in order to promote dehydration reaction. After prolonged exposure of monomeric valine to elevated temperatures and pressures, the products were analyzed by liquid chromatography mass spectrometry comparing their retention times and masses. We identified linear peptides that ranged in size from dimer to hexamer, as well as a cyclic dimer. Previous studies that attempted abiotic oligomerization of valine in the absence of a catalyst have never reported valine peptides larger than a dimer. Increased reaction temperature increased the dissociative decomposition of valine and valine peptides to products such as glycine, β-alanine, ammonia, and amines by processes such as deamination, decarboxylation, and cracking. The amount of residual valine and peptide yields was greater at higher pressures at a given temperature, pressure, and reaction time. This suggests that dissociative decomposition of valine and valine peptides is reduced by pressure. Our findings are relevant to the investigation of diagenetic processes in prebiotic marine sediments where similar pressures occur under water-poor conditions. These findings also suggest that amino acids, such as valine, could have been polymerized to peptides in deep prebiotic marine sediments within a few hundred million years.

  3. Effects of ibuprofen on exercise-induced muscle soreness and indices of muscle damage.

    PubMed Central

    Donnelly, A E; Maughan, R J; Whiting, P H

    1990-01-01

    Thirty-two volunteers participated in a two-period crossover study in which ibuprofen was tested against an identical placebo for its effectiveness in reducing muscle soreness and damage after two bouts of downhill running. Subjective soreness, quadriceps isometric strength and isometric endurance time at 50 percent of maximum strength, serum activities of creatine kinase, lactate dehydrogenase and aspartate transaminase and serum levels of creatinine and urea were recorded at intervals up to 72 hours after exercise. Each downhill run produced muscle soreness, and a decline in muscle strength and 50 percent endurance time, although these parameters were unaffected by ibuprofen treatment. All serum parameters measured increased after both runs, but for the three enzymes this increase was smaller after the second run. Serum creatine kinase and urea levels were higher in the ibuprofen group after both runs. These results indicate that ibuprofen is not an appropriate treatment for delayed onset muscle soreness and damage. PMID:2078806

  4. The effects of land vs. aquatic plyometrics on power, torque, velocity, and muscle soreness in women.

    PubMed

    Robinson, Leah E; Devor, Steven T; Merrick, Mark A; Buckworth, Janet

    2004-02-01

    The purpose of this study was to compare changes in performance indicators (power, torque, and velocity) and muscle soreness between plyometric training on land and in water. Thirty-two college age women were randomly assigned to 8 weeks of an identical plyometric training program on land or in an aquatic setting. Performance indicators were assessed pretraining, midtraining, and posttraining. Muscle soreness (ordinal scale) and pain sensitivity (palpation) were assessed after a training bout (0, 48, and 96 hours) during the first week of training and when training intensity was increased (weeks 3 and 6). Performance indictors increased for both groups (pretraining < midtraining < posttraining, p < or = 0.001). Muscle soreness was significantly greater in the land compared to the aquatic plyometric training group at baseline and each time training intensity was increased, p = 0.01. Aquatic plyometrics provided the same performance enhancement benefits as land plyometrics with significantly less muscle soreness.

  5. Pilot Study on the Effect of Grounding on Delayed-Onset Muscle Soreness

    PubMed Central

    Brown, Dick; Hill, Michael

    2010-01-01

    Abstract Objectives The purpose of this pilot study was to determine whether there are markers that can be used to study the effects of grounding on delayed-onset muscle soreness (DOMS). Design and subjects Eight (8) healthy subjects were exposed to an eccentric exercise that caused DOMS in gastrocnemius muscles of both legs. Four (4) subjects were grounded with electrode patches and patented conductive sheets connected to the earth. Four (4) control subjects were treated identically, except that the grounding systems were not connected to the earth. Outcome measures Complete blood counts, blood chemistry, enzyme chemistry, serum and saliva cortisols, magnetic resonance imaging and spectroscopy and pain levels were taken at the same time of day before the eccentric exercise and 24, 48, and 72 hours afterwards. Parameters consistently differing by 10% or more, normalized to baseline, were considered worthy of further study. Results Parameters that differed by these criteria included white blood cell counts, bilirubin, creatine kinase, phosphocreatine/inorganic phosphate ratios, glycerolphosphorylcholine, phosphorylcholine, the visual analogue pain scale, and pressure measurements on the right gastrocnemius. Conclusions In a pilot study, grounding the body to the earth alters measures of immune system activity and pain. Since this is the first intervention that appears to speed recovery from DOMS, the pilot provides a basis for a larger study. PMID:20192911

  6. Whole-Body Vibration While Squatting and Delayed-Onset Muscle Soreness in Women

    PubMed Central

    Dabbs, Nicole C.; Black, Christopher D.; Garner, John

    2015-01-01

    Context  Research into alleviating muscle pain and symptoms in individuals after delayed-onset muscle soreness (DOMS) has been inconsistent and unsuccessful in demonstrating a useful recovery modality. Objective  To investigate the effects of short-term whole-body vibration (WBV) on DOMS over a 72-hour period after a high-intensity exercise protocol. Design  Randomized controlled clinical trial. Setting  University laboratory. Patients or Other Participants  Thirty women volunteered to participate in 4 testing sessions and were assigned randomly to a WBV group (n = 16; age = 21.0 ± 1.9 years, height = 164.86 ± 6.73 cm, mass = 58.58 ± 9.32 kg) or a control group (n = 14; age = 22.00 ± 1.97 years, height = 166.65 ± 8.04 cm, mass = 58.69 ± 12.92 kg). Intervention(s)  Participants performed 4 sets to failure of single-legged split squats with 40% of their body weight to induce muscle soreness in the quadriceps. The WBV or control treatment was administered each day after DOMS. Main Outcome Measure(s)  Unilateral pressure-pain threshold (PPT), range of motion (ROM), thigh circumference, and muscle-pain ratings of the quadriceps were collected before and for 3 days after high-intensity exercise. Each day, we collected 3 sets of measures, consisting of 1 measure before the WBV or control treatment protocol (pretreatment) and 2 sets of posttreatment measures. Results  We observed no interactions for PPT, thigh circumference, and muscle pain (P > .05). An interaction was found for active ROM (P = .01), with the baseline pretreatment measure greater than the measures at baseline posttreatment 1 through 48 hours posttreatment 2 in the WBV group. For PPT, a main effect for time was revealed (P < .05), with the measure at baseline pretreatment greater than at 24 hours pretreatment and all other time points for the vastus medialis, greater than 24 hours pretreatment through 48 hours posttreatment 2 for the vastus lateralis, and greater than 24 hours

  7. Hybrid equation/agent-based model of ischemia-induced hyperemia and pressure ulcer formation predicts greater propensity to ulcerate in subjects with spinal cord injury.

    PubMed

    Solovyev, Alexey; Mi, Qi; Tzen, Yi-Ting; Brienza, David; Vodovotz, Yoram

    2013-01-01

    Pressure ulcers are costly and life-threatening complications for people with spinal cord injury (SCI). People with SCI also exhibit differential blood flow properties in non-ulcerated skin. We hypothesized that a computer simulation of the pressure ulcer formation process, informed by data regarding skin blood flow and reactive hyperemia in response to pressure, could provide insights into the pathogenesis and effective treatment of post-SCI pressure ulcers. Agent-Based Models (ABM) are useful in settings such as pressure ulcers, in which spatial realism is important. Ordinary Differential Equation-based (ODE) models are useful when modeling physiological phenomena such as reactive hyperemia. Accordingly, we constructed a hybrid model that combines ODEs related to blood flow along with an ABM of skin injury, inflammation, and ulcer formation. The relationship between pressure and the course of ulcer formation, as well as several other important characteristic patterns of pressure ulcer formation, was demonstrated in this model. The ODE portion of this model was calibrated to data related to blood flow following experimental pressure responses in non-injured human subjects or to data from people with SCI. This model predicted a higher propensity to form ulcers in response to pressure in people with SCI vs. non-injured control subjects, and thus may serve as novel diagnostic platform for post-SCI ulcer formation.

  8. Effects of stretching before and after exercising on muscle soreness and risk of injury: systematic review

    PubMed Central

    Herbert, Rob D; Gabriel, Michael

    2002-01-01

    Objective To determine the effects of stretching before and after exercising on muscle soreness after exercise, risk of injury, and athletic performance. Method Systematic review. Data sources Randomised or quasi-randomised studies identified by searching Medline, Embase, CINAHL, SPORTDiscus, and PEDro, and by recursive checking of bibliographies. Main outcome measures Muscle soreness, incidence of injury, athletic performance. Results Five studies, all of moderate quality, reported sufficient data on the effects of stretching on muscle soreness to be included in the analysis. Outcomes seemed homogeneous. Stretching produced small and statistically non-significant reductions in muscle soreness. The pooled estimate of reduction in muscle soreness 24 hours after exercising was only 0.9 mm on a 100 mm scale (95% confidence interval −2.6 mm to 4.4 mm). Data from two studies on army recruits in military training show that muscle stretching before exercising does not produce useful reductions in injury risk (pooled hazard ratio 0.95, 0.78 to 1.16). Conclusions Stretching before or after exercising does not confer protection from muscle soreness. Stretching before exercising does not seem to confer a practically useful reduction in the risk of injury, but the generality of this finding needs testing. Insufficient research has been done with which to determine the effects of stretching on sporting performance. What is already known on this topicReviews of the effects of stretching before exercising have drawn conflicting conclusionsThe literature on effects of stretching before and after exercising on muscle soreness and risk of injury has not been systematically reviewedWhat this study addsStretching before and after exercising does not confer protection from muscle soreness and stretching before exercise does not seem to confer a practically useful reduction in the risk of injury PMID:12202327

  9. Investigation Of Adhesion Formation In New Stainless Steel Trim Spring Operated Pressure Relief Valves

    SciTech Connect

    Gross, Robert E.; Bukowski, Julia V.; Goble, William M.

    2013-04-16

    Examination of proof test data for new (not previously installed) stainless steel (SS) trim spring operated pressure relief valves (SOPRV) reveals that adhesions form between the seat and disc in about 46% of all such SOPRV. The forces needed to overcome these adhesions can be sufficiently large to cause the SOPRV to fail its proof test (FPT) prior to installation. Furthermore, a significant percentage of SOPRV which are found to FPT are also found to ''fail to open'' (FTO) meaning they would not relief excess pressure in the event of an overpressure event. The cases where adhesions result in FTO or FPT appear to be confined to SOPRV with diameters < 1 in and set pressures < 150 psig and the FTO are estimated to occur in 0.31% to 2.00% of this subpopulation of SS trim SOPRV. The reliability and safety implications of these finding for end-users who do not perform pre-installation testing of SOPRV are discussed.

  10. Dissociation of CH4 at high pressures and temperatures: diamond formation in giant planet interiors?

    PubMed

    Benedetti, L R; Nguyen, J H; Caldwell, W A; Liu, H; Kruger, M; Jeanloz, R

    1999-10-01

    Experiments using laser-heated diamond anvil cells show that methane (CH4) breaks down to form diamond at pressures between 10 and 50 gigapascals and temperatures of about 2000 to 3000 kelvin. Infrared absorption and Raman spectroscopy, along with x-ray diffraction, indicate the presence of polymeric hydrocarbons in addition to the diamond, which is in agreement with theoretical predictions. Dissociation of CH4 at high pressures and temperatures can influence the energy budgets of planets containing substantial amounts of CH4, water, and ammonia, such as Uranus and Neptune.

  11. Pulsed Ultrasound Fails To Diminish Delayed-Onset Muscle Soreness Symptoms

    PubMed Central

    Stay, Jeffrey C.; Richard, Mark D.; Draper, David O.; Schulthies, Shane S.; Durrant, Earlene

    1998-01-01

    Objective: We investigated the effects of pulsed ultrasound on swelling, muscle soreness perception, relaxed-elbow extension angle, and muscular strength. Design and Setting: Eight sets of concentric and eccentric actions induced delayed-onset muscle soreness of the elbow flexors. Group 1 received 20% pulsed ultrasound treatments (1-MHz, 7 minutes, 1.5 W/ cm2 temporal peak intensity) twice a day immediately after postexercise assessments and at 3, 24, 27, 48, 51, 72, and 75 hours postexercise. Group 2 received sham treatments immediately after postexercise assessments and at 3,27, 51, and 75 hours postexercise and true treatments of pulsed ultrasound at 24, 48, and 72 hours postexercise. Group 3 received sham treatments of no ultrasonic output immediately after postexercise assessments and at 3, 24, 27, 48, 51, 72, and 75 hours postexercise. Subjects: Thirty-six college-age females. Measurements: We recorded upper-arm circumference, perceived soreness, relaxed-elbow extension angle, and elbow-flexion strength before (pretest), immediately postexercise, and at 24, 48, 72, and 96 hours postexercise. Results: We noted differences over time but no treatment effect between groups or interactions between time and group for upper-arm circumference, perceived soreness, relaxed-elbow extension angle, or elbow-flexion strength. Conclusions: Pulsed ultrasound as used in this study did not significantly diminish the effects of delayed-onset muscle soreness on soreness perception, swelling, relaxed-elbow extension angle, and strength. PMID:16558532

  12. Enhancing Magnesite Formation at Low Temperature and High CO2 Pressure: The Impact of Seed Crystals and Minor Components

    SciTech Connect

    Felmy, Andrew R.; Qafoku, Odeta; Arey, Bruce W.; Kovarik, Libor; Liu, Jia; Perea, Daniel E.; Ilton, Eugene S.

    2015-02-24

    The formation of magnesite was followed in aqueous solution containing initially added Mg(OH)2 equilibrated with supercritical carbon dioxide (90 atm pressure, 50°C) in the presence of introduced magnesite particles and minor components, Co(II). As expected, the introduction of magnesite particles accelerated the formation of magnesite from solution. However, the formation rate of magnesite was even greater when small concentrations of Co(II) were introduced, indicating that the increased rate of magnesite formation in the presence of Co(II) was not solely due to the addition of a growth promoting surface. Detailed analysis of the magnesite particles by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and atom probe tomography (APT) revealed that the originally added Co(II) was concentrated in the center but also present throughout the growing magnesite particles. Addition of the Co(II) in different chemical forms (i.e. as solid phase CoCO3 or Co(OH)2) could alter the growth rate of magnesite depending upon the addition of bicarbonate to the starting solution. Geochemical modeling calculations indicate that this difference is related to the thermodynamic stability of these different phases in the initial solutions. More broadly, these results indicate that the presence of even small concentrations of foreign ions that form carbonate compounds with a similar structure as magnesite can be incorporated into the magnesite lattice, accelerating the formation of anhydrous carbonates in natural environments.

  13. First Evidence of Rh Nano-Hydride Formation at Low Pressure.

    PubMed

    Zlotea, Claudia; Oumellal, Yassine; Msakni, Mariem; Bourgon, Julie; Bastide, Stéphane; Cachet-Vivier, Christine; Latroche, Michel

    2015-07-08

    Rh-based nanoparticles supported on a porous carbon host were prepared with tunable average sizes ranging from 1.3 to 3.0 nm. Depending on the vacuum or hydrogen environment during thermal treatment, either Rh metal or hydride is formed at nanoscale, respectively. In contrast to bulk Rh that can form a hydride phase under 4 GPa pressure, the metallic Rh nanoparticles (∼2.3 nm) absorb hydrogen and form a hydride phase at pressure below 0.1 MPa, as evidenced by the presence of a plateau pressure in the pressure-composition isotherm curves at room temperature. Larger metal nanoparticles (∼3.0 nm) form only a solid solution with hydrogen under similar conditions. This suggests a nanoscale effect that drastically changes the Rh-H thermodynamics. The nanosized Rh hydride phase is stable at room temperature and only desorbs hydrogen above 175 °C. Within the present hydride particle size range (1.3-2.3 nm), the hydrogen desorption is size-dependent, as proven by different thermal analysis techniques.

  14. Magnesite formation from MgO and CO2 at the pressures and temperatures of Earth's mantle

    SciTech Connect

    Scott, Henry P.; Doczy, Vincent M.; Frank, Mark R.; Hasan, Maggie; Lin, Jung-Fu; Yang, Jing

    2013-08-02

    Magnesite (MgCO3) is an important phase for the carbon cycle in and out of the Earth’s mantle. Its comparably large P-T stability has been inferred for several years based on the absence of its decomposition in experiments. Here we report the first experimental evidence for synthesis of magnesite out of its oxide components (MgO and CO2) at P-T conditions relevant to the Earth’s mantle. Magnesite formation was observed in situ using synchrotron X-ray diffraction, coupled with laser-heated diamond-anvil cells (DACs), at pressures and temperatures of Earth’s mantle. Despite the existence of multiple high-pressure CO2 polymorphs, the magnesite-forming reaction was observed to proceed at pressures ranging from 5 to 40 GPa and temperatures between 1400 and 1800 K. No other pressure-quenchable materials were observed to form via the MgO + CO2 = MgCO3 reaction. This work further strengthens the notion that magnesite may indeed be the primary host phase for oxidized carbon in the deep Earth.

  15. Prophylactic effect of dexamethasone in reducing postoperative sore throat

    PubMed Central

    Park, Sun-young; Lee, Ae-ri; Cho, Sung-Hwan; Chae, Won Seok; Jin, Hee Cheol; Lee, Jeong Seok; Kim, Yong Ik

    2010-01-01

    Background This study was performed to compare the effectiveness of prophylactic dexamethasone and postintubation dexamethasone in reducing the incidence and severity of postoperative sore throat (POST). Methods This was a prospective, randomized, double-blind clinical trial. The study population consisted of 70 patients between 20 and 60 years old who were classified as American Society of Anesthesiologists I-II and were scheduled for elective laparoscopic cholecystectomy. The patients were divided randomly into two groups. Patients in the prophylactic and postintubation groups received intravenous injection of 10 mg of dexamethasone 30 min before or after tracheal intubation, respectively. The patients were interviewed 1, 6, and 24 h after the operation. The incidence and severity of POST were recorded. Results The severity scores of POST at 1 and 6 h after the operation were significantly lower in the prophylactic group than in the postintubation group. There were no significant differences in the incidence of POST during the 24 h after the operation between the two groups (22/32 in the prophylactic group vs. 27/34 in the postintubation group, P = 0.403). Conclusions Intravenous injection of 10 mg of dexamethasone was more effective in reducing the severity of POST when administered before tracheal intubation compared with after tracheal intubation. PMID:20498806

  16. Delayed onset muscle soreness: Involvement of neurotrophic factors.

    PubMed

    Mizumura, Kazue; Taguchi, Toru

    2016-01-01

    Delayed-onset muscle soreness (DOMS) is quite a common consequence of unaccustomed strenuous exercise, especially exercise containing eccentric contraction (lengthening contraction, LC). Its typical sign is mechanical hyperalgesia (tenderness and movement related pain). Its cause has been commonly believed to be micro-damage of the muscle and subsequent inflammation. Here we present a brief historical overview of the damage-inflammation theory followed by a discussion of our new findings. Different from previous observations, we have observed mechanical hyperalgesia in rats 1-3 days after LC without any apparent microscopic damage of the muscle or signs of inflammation. With our model we have found that two pathways are involved in inducing mechanical hyperalgesia after LC: activation of the B2 bradykinin receptor-nerve growth factor (NGF) pathway and activation of the COX-2-glial cell line-derived neurotrophic factor (GDNF) pathway. These neurotrophic factors were produced by muscle fibers and/or satellite cells. This means that muscle fiber damage is not essential, although it is sufficient, for induction of DOMS, instead, NGF and GDNF produced by muscle fibers/satellite cells play crucial roles in DOMS.

  17. Effects of topical dexamethasone in postoperative sore throat

    PubMed Central

    Kim, Soo Bin; Lee, Wonjin; Ki, Seunghee; Kim, Myoung-Hun; Cho, Kwangrae; Lim, Se Hun; Lee, Kun Moo; Choi, Deul-Nyuck; Oh, Minkyung

    2017-01-01

    Background Postoperative sore throat (POST) is a complication that undermines patient satisfaction and increases discomfort in the postoperative period. The present study examined the effects of dexamethasone gargle and endotracheal tube cuff soaking on the incidence and severity of POST. Methods Ninety patients undergoing laparoscopic cholecystectomy were randomly allocated into three groups: 0.9% normal saline gargling and tube soaking (group C), 0.05% dexamethasone solution gargling and 0.9% normal saline tube soaking (group G), 0.9% normal saline gargling and 0.05% dexamethasone tube soaking (group S). The incidence and severity of POST were then assessed and recorded at 24 hours after surgery. Results The total incidence of POST was significantly different among the groups (P < 0.05), and group S exhibited a significantly lower incidence of POST than group C (P < 0.0167). In addition, the POST intensity of group G and group S was less severe than those of group C (Both P < 0.0167). Conclusions Among patients undergoing laparoscopic cholecystectomy, those who gargled with 0.05% dexamethasone solution exhibited lower severity of POST than the control group, and those whose endotracheal tube cuff was soaked in the dexamethasone solution before intubation exhibited significantly lower incidence and severity of POST than the control group. PMID:28184268

  18. Influence of flowing helium gas on plasma plume formation in atmospheric pressure plasma

    SciTech Connect

    Yambe, Kiyoyuki; Konda, Kohmei; Ogura, Kazuo

    2015-05-15

    We have studied atmospheric pressure plasma generated using a quartz tube, helium gas, and a foil electrode by applying RF high voltage. The atmospheric pressure plasma in the form of a bullet is released as a plume into the atmosphere. The helium gas flowing out of quartz tube mixes with air, and the flow channel is composed of the regions of flowing helium gas and air. The plasma plume length is equivalent to the reachable distance of flowing helium gas. Although the amount of helium gas on the flow channel increases by increasing the inner diameter of quartz tube at the same gas flow velocity, the plasma plume length peaks at around 8 m/s of gas flow velocity, which is the result that a flow of helium gas is balanced with the amount of gas. The plasma plume is formed at the boundary region where the flow of helium gas is kept to the wall of the air.

  19. Kinetics of microstructure formation of high-pressure induced gel from a whey protein isolate

    NASA Astrophysics Data System (ADS)

    He, Jin-Song; Yang, Hongwei; Zhu, Wanpeng; Mu, Tai-Hua

    2010-03-01

    The kinetic process of pressure-induced gelation of whey protein isolate (WPI) solutions was studied using in situ light scattering. The relationship of the logarithm of scattered light intensity (I) versus time (t) was linear after the induced time and could be described by the Cahn-Hilliard linear theory. With increasing time, the scattered intensity deviated from the exponential relationship, and the time evolution of the scattered light intensity maximum Im and the corresponding wavenumber qm could be described in terms of the power-law relationship as Im~fβ and qm~f-α, respectively. These results indicated that phase separation occurred during the gelation of WPI solutions under high pressure.

  20. Selective Formation of Trimethylene Carbonate (TMC): Atmospheric Pressure Carbon Dioxide Utilization

    PubMed Central

    Buckley, Benjamin R; Patel, Anish P; Wijayantha, K G Upul

    2015-01-01

    Carbon dioxide utilisation (CDU) is currently gaining increased interest due to the abundance of CO2 and its possible application as a C1 building block. We herein report the first example of atmospheric pressure carbon dioxide incorporation into oxetane to selectively form trimethylene carbonate (TMC), which is a significant challenge as TMC is thermodynamically less favoured than its corresponding co-polymer. PMID:26213485

  1. Rapid Association Reactions at Low Pressure: Impact on the Formation of Hydrocarbons on Titan

    NASA Astrophysics Data System (ADS)

    Vuitton, V.; Yelle, R. V.; Lavvas, P.; Klippenstein, S. J.

    2012-01-01

    Photochemical models of Titan's atmosphere predict that three-body association reactions are the main production route for several major hydrocarbons. The kinetic rate constants of these reactions strongly depend on density and are therefore only important in Titan's lower atmosphere. However, radiative association reactions do not depend on pressure. The possible existence of large rates at low density suggests that association reactions could significantly affect the chemistry of Titan's upper atmosphere and better constraints for them are required. The kinetic parameters of these reactions are extremely difficult to constrain by experimental measurements as the low pressure of Titan's upper atmosphere cannot be reproduced in the laboratory. However, in the recent years, theoretical calculations of kinetics parameters have become more and more reliable. We therefore calculated several radical-radical and radical-molecule association reaction rates using transition state theory. The calculations indicate that association reactions are fast even at low pressure for adducts having as few as four C atoms. These drastic changes have however only moderate consequences for Titan's composition. Locally, mole fractions can vary by as much as one order of magnitude but the column-integrated production and condensation rates of hydrocarbons change only by a factor of a few. We discuss the impact of these results for the organic chemistry. It would be very interesting to check the impact of these new rate constants on other environments, such as giant and extrasolar planets as well as the interstellar medium.

  2. RAPID ASSOCIATION REACTIONS AT LOW PRESSURE: IMPACT ON THE FORMATION OF HYDROCARBONS ON TITAN

    SciTech Connect

    Vuitton, V.; Klippenstein, S. J. E-mail: yelle@lpl.arizona.edu E-mail: sjk@anl.gov

    2012-01-01

    Photochemical models of Titan's atmosphere predict that three-body association reactions are the main production route for several major hydrocarbons. The kinetic rate constants of these reactions strongly depend on density and are therefore only important in Titan's lower atmosphere. However, radiative association reactions do not depend on pressure. The possible existence of large rates at low density suggests that association reactions could significantly affect the chemistry of Titan's upper atmosphere and better constraints for them are required. The kinetic parameters of these reactions are extremely difficult to constrain by experimental measurements as the low pressure of Titan's upper atmosphere cannot be reproduced in the laboratory. However, in the recent years, theoretical calculations of kinetics parameters have become more and more reliable. We therefore calculated several radical-radical and radical-molecule association reaction rates using transition state theory. The calculations indicate that association reactions are fast even at low pressure for adducts having as few as four C atoms. These drastic changes have however only moderate consequences for Titan's composition. Locally, mole fractions can vary by as much as one order of magnitude but the column-integrated production and condensation rates of hydrocarbons change only by a factor of a few. We discuss the impact of these results for the organic chemistry. It would be very interesting to check the impact of these new rate constants on other environments, such as giant and extrasolar planets as well as the interstellar medium.

  3. Experimental study of fractal clusters formation from nanoparticles synthesized by atmospheric pressure plasma-enhanced chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Mishin, Maxim V.; Protopopova, Vera S.; Alexandrov, Sergey E.

    2014-11-01

    This paper presents the experimental results from the fractal structures formation from nanoparticles of silicone dioxide deposited on the silicon substrate surface. Nanoparticles are synthesized by atmospheric pressure plasma-enhanced chemical vapor deposition with the use of capacitively coupled radio frequency (13.56 MHz) discharge sustained in helium atmosphere. Tetraethoxysilane is chosen as the test precursor. Correlation between the morphology of obtained deposits and the process parameters is found. The capability of nanoparticles movement along the deposit surface in local near-surface electric field is demonstrated. The empirical model that satisfactorily explained the mechanism of fractal clusters formation from nanoparticles on the substrate surface is developed. The model indicates that the dynamics of deposit morphology variations is determined by two competing processes: electrical charge transfer by nanoparticles to the deposit surface and electrical charge running off over the surface under conditions of changeable conductivity of the deposit surface.

  4. Surface pressure affects B-hordein network formation at the air-water interface in relation to gastric digestibility.

    PubMed

    Yang, Jingqi; Huang, Jun; Zeng, Hongbo; Chen, Lingyun

    2015-11-01

    Protein interfacial network formation under mechanical pressure and its influence on degradation was investigated at molecular level using Langmuir-Blodgett B-hordein monolayer as a 2D model. Surface properties, such as surface pressure, dilatational and shear rheology and the surface pressure--area (π-A) isotherm, of B-hordein at air-water interface were analyzed by tensiometer, rheometer and a Langmuir-Blodgett trough respectively. B-Hordein conformation and orientation under different surface pressures were determined by polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS). The interfacial network morphology was observed by atomic force microscopy (AFM). B-Hordein could reduce the air-water surface tension rapidly to ∼ 45 mN/m and form a solid-like network with high rheological elasticity and compressibility at interface, which could be a result of interactions developed by intermolecular β-sheets. The results also revealed that B-hordein interfacial network switched from an expanded liquid phase to a solid-like film with increasing compression pressure. The orientation of B-hordein was parallel to the surface when in expended liquid phase, whereas upon compression, the hydrophobic repetitive region tilted away from water phase. When compressed to 30 mN/m, a strong elastic network was formed at the interface, and it was resistant to a harsh gastric-like environment of low pH and pepsin. This work generated fundamental knowledge, which suggested the potential to design B-hordein stabilized emulsions and encapsulations with controllable digestibility for small intestine targeted delivery of bioactive compounds.

  5. Soot Formation and Destruction in High-Pressure Flames with Real Fuels

    DTIC Science & Technology

    2013-08-18

    Optical investigations on soot forming methane - oxygen flames,‟ Combust. Sci. Tech. 5, 263 (1972). D‟Anna, D. and Kent, J.H., „Aromatic formation...07/31/2013 8.00 Wei Jing, William L. Roberts, Tiegang Fang. Effects of Temperature and Oxygen on Spray and Combustion Characteristics of Diesel and...Temperature and Oxygen Concentration on Diesel Spray Combustion Using a Single-Nozzle Injector in a Constant Volume Combustion Chamber, Combustion

  6. Carbon dioxide storage in marine sediments - dissolution, transport and hydrate formation kinetics from high-pressure experiments

    NASA Astrophysics Data System (ADS)

    Bigalke, N. K.; Savy, J. P.; Pansegrau, M.; Aloisi, G.; Kossel, E.; Haeckel, M.

    2009-12-01

    By satisfying thermodynamic framework conditions for CO2 hydrate formation, pressures and temperatures of the deep marine environment are unique assets for sequestering CO2 in clathrates below the seabed. However, feasibility and safety of this storage option require an accurate knowledge of the rate constants governing the speed of physicochemical reactions following the injection of the liquefied gas into the sediments. High-pressure experiments designed to simulate the deep marine environment open the possibility to obtain the required parameters for a wide range of oceanic conditions. In an effort to constrain mass transfer coefficients and transport rates of CO2 in(to) the pore water of marine sediments first experiments were targeted at quantifying the rate of CO2 uptake by de-ionized water and seawater across a two-phase interface. The nature of the interface was controlled by selecting p and T to conditions within and outside the hydrate stability field (HSF) while considering both liquid and gaseous CO2. Concentration increase and hydrate growth were monitored by Raman spectroscopy. The experiments revealed anomalously fast transport rates of dissolved CO2 at conditions both inside and outside the HSF. While future experiments will further elucidate kinetics of CO2 transport and hydrate formation, these first results could have major significance to safety-related issues in the discussion of carbon storage in the marine environment.

  7. Formation and stability of D-limonene organogel-based nanoemulsion prepared by a high-pressure homogenizer.

    PubMed

    Zahi, Mohamed Reda; Wan, Pingyu; Liang, Hao; Yuan, Qipeng

    2014-12-31

    D-limonene organogel-based nanoemulsion was prepared by high-pressure homogenization technology. The organogelator type had a major role on the formation of the formulations, in which stearic acid has given nanoemulsions with the smallest droplet size. The surfactant type and concentration also had an appreciable effect on droplet formation, with Tween 80 giving a mean droplet diameter (d ≈ 112 nm) among a range of non-ionic surfactants (Tween 20, 40, 60, 80, and 85). In addition, high-pressure homogenization conditions played a key role in the nanoemulsion preparation. The stability of d-limonene organogel-based nanoemulsion was also investigated under two different temperatures (4 and 28 °C) through 2 weeks of storage. Results showed a good stability of the formulations, which is maybe due to the incorporation of D-limonene into the organogel prior to homogenization. This study may have a valuable contribution for the design and use of organogel-based nanoemulsion as a delivery system in food.

  8. Formation and characterization of hydrophobic glass surface treated by atmospheric pressure He/CH4 plasma

    NASA Astrophysics Data System (ADS)

    Noh, Sooryun; Youn Moon, Se

    2014-01-01

    Atmospheric pressure helium plasmas, generated in the open air by 13.56 MHz rf power, were applied for the glass surface wettability modification. The plasma gas temperature, measured by the spectroscopic method, was under 400 K which is low enough to treat the samples without thermal damages. The hydrophobicity of the samples determined by the water droplet contact angle method was dependent on the methane gas content and the plasma exposure time. Adding the methane gas by a small amount of 0.25%, the contact angle was remarkably increased from 10° to 83° after the 10 s plasma treatment. From the analysis of the treated surface and the plasma, it was shown that the deposition of alkane functional groups such as C-H stretch, CH2 bend, and CH3 bend was one of the contributing factors for the hydrophobicity development. In addition, the hydrophobic properties lasted over 2 months even after the single treatment. From the results, the atmospheric pressure plasma treatment promises the fast and low-cost method for the thermally-weak surface modification.

  9. Microfluidic EDGE emulsification: the importance of interface interactions on droplet formation and pressure stability

    NASA Astrophysics Data System (ADS)

    Sahin, Sami; Bliznyuk, Olesya; Rovalino Cordova, Ana; Schroën, Karin

    2016-05-01

    The fact that interactions of components with interfaces can influence processes is well-known; e.g. deposit accumulation on heat exchangers and membrane fouling lead to additional resistances against heat and mass transfer, respectively. In microfluidic emulsification, the situation is even more complex. Component accumulation at the liquid/liquid interface is necessary for emulsion stability, while undesired at the solid/liquid interface where it may change wettability. For successful emulsification both aspects need to be controlled, and that is investigated in this paper for o/w emulsification with microfluidic EDGE devices. These devices were characterised previously, and can be used to detect small wettability changes through e.g. the pressure stability of the device. We used various oil/emulsifier combinations (alkanes, vegetable oil, surfactants and proteins) and related droplet size and operational pressure stability to component interactions with the solid surface and liquid interface. Surfactants with a strong interaction with glass always favour emulsification, while surfactants that have week interactions with the surface can be replaced by vegetable oil that interacts strongly with glass, resulting in loss of emulsification. Our findings clearly show that an appropriate combination of construction material and emulsion components is needed to achieve successful emulsification in microfluidic EDGE devices.

  10. Microfluidic EDGE emulsification: the importance of interface interactions on droplet formation and pressure stability

    PubMed Central

    Sahin, Sami; Bliznyuk, Olesya; Rovalino Cordova, Ana; Schroën, Karin

    2016-01-01

    The fact that interactions of components with interfaces can influence processes is well-known; e.g. deposit accumulation on heat exchangers and membrane fouling lead to additional resistances against heat and mass transfer, respectively. In microfluidic emulsification, the situation is even more complex. Component accumulation at the liquid/liquid interface is necessary for emulsion stability, while undesired at the solid/liquid interface where it may change wettability. For successful emulsification both aspects need to be controlled, and that is investigated in this paper for o/w emulsification with microfluidic EDGE devices. These devices were characterised previously, and can be used to detect small wettability changes through e.g. the pressure stability of the device. We used various oil/emulsifier combinations (alkanes, vegetable oil, surfactants and proteins) and related droplet size and operational pressure stability to component interactions with the solid surface and liquid interface. Surfactants with a strong interaction with glass always favour emulsification, while surfactants that have week interactions with the surface can be replaced by vegetable oil that interacts strongly with glass, resulting in loss of emulsification. Our findings clearly show that an appropriate combination of construction material and emulsion components is needed to achieve successful emulsification in microfluidic EDGE devices. PMID:27230981

  11. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

    PubMed

    Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

    2013-01-01

    Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ(13)Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate.

  12. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

    PubMed Central

    Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

    2013-01-01

    Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0–100 MPa) and temperature (0–70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ13Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate. PMID

  13. Transdermal deferoxamine prevents pressure-induced diabetic ulcers.

    PubMed

    Duscher, Dominik; Neofytou, Evgenios; Wong, Victor W; Maan, Zeshaan N; Rennert, Robert C; Inayathullah, Mohammed; Januszyk, Michael; Rodrigues, Melanie; Malkovskiy, Andrey V; Whitmore, Arnetha J; Walmsley, Graham G; Galvez, Michael G; Whittam, Alexander J; Brownlee, Michael; Rajadas, Jayakumar; Gurtner, Geoffrey C

    2015-01-06

    There is a high mortality in patients with diabetes and severe pressure ulcers. For example, chronic pressure sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia inducible factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-induced and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a pressure-induced ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation.

  14. Transdermal deferoxamine prevents pressure-induced diabetic ulcers

    PubMed Central

    Duscher, Dominik; Neofytou, Evgenios; Wong, Victor W.; Maan, Zeshaan N.; Rennert, Robert C.; Januszyk, Michael; Rodrigues, Melanie; Malkovskiy, Andrey V.; Whitmore, Arnetha J.; Galvez, Michael G.; Whittam, Alexander J.; Brownlee, Michael; Rajadas, Jayakumar; Gurtner, Geoffrey C.

    2015-01-01

    There is a high mortality in patients with diabetes and severe pressure ulcers. For example, chronic pressure sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia inducible factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-induced and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a pressure-induced ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation. PMID:25535360

  15. Prophylactic tolperisone for post-exercise muscle soreness causes reduced isometric force--a double-blind randomized crossover control study.

    PubMed

    Bajaj, Prem; Arendt-Nielsen, Lars; Madeleine, Pascal; Svensson, Peter

    2003-01-01

    The role of tolperisone hydrochloride, a centrally acting muscle relaxant in relieving painful muscle spasm is recently being discussed. The present study hypothesizes that the prophylactic use of tolperisone hydrochloride may effectively relieve post-exercise muscle soreness, based on the spasm theory of exercise pain. Twenty male volunteers, aged 25.2 +/- 0.82 years (mean +/- SEM) participated in 10 sessions in which they received oral treatment with placebo or the centrally acting muscle relaxant tolperisone hydrochloride (150 mg) three times daily for 8 days, in randomized crossover double-blind design. Time course assessments were made for pressure pain threshold, Likert's pain score (0-5), pain areas, range of abduction, isometric force, and electromyography (EMG) root mean square (RMS) during maximum voluntary isometric force on day 1 and 6, immediately after an eccentric exercise of first dorsal interosseous muscle, and 24 and 48 h after the exercise. Treatment with placebo or tolperisone hydrochloride was initiated immediately after the assessments on the first day baseline assessments. On the sixth day baseline investigations were repeated and then the subjects performed six bouts of standardized intense eccentric exercise of first dorsal interosseous muscle for provocation of post-exercise muscle soreness (PEMS). Perceived intensity of warmth, tiredness, soreness and pain during the exercise bouts were recorded on a 10 cm visual analogue pain scale. VAS scores and pressure pain thresholds did not differ between tolperisone and placebo treatment. All VAS scores increased during the exercise bouts 2, 3, 4, 5 and 6 as compared to bout 1. Increased pain scores and pain areas were reported immediately after, 24 and 48 h after exercise. Pressure pain thresholds were reduced at 24 and 48 h after the exercise in the exercised hand. Range of abduction of the index finger was reduced immediately after the exercise and was still reduced at 24 h as compared to the

  16. Diagnostics and active species formation in an atmospheric pressure helium sterilization plasma source

    NASA Astrophysics Data System (ADS)

    Simon, A.; Anghel, S. D.; Papiu, M.; Dinu, O.

    2009-01-01

    Systematic spectroscopic studies and diagnostics of an atmospheric pressure radiofrequency (13.56 MHz) He plasma is presented. The discharge is an intrinsic part of the resonant circuit of the radiofrequency oscillator and was obtained using a monoelectrode type torch, at various gas flow-rates (0.1-6.0 l/min) and power levels (0-2 W). As function of He flow-rate and power the discharge has three developing stages: point-like plasma, spherical plasma and ellipsoidal plasma. The emission spectra of the plasma were recorded and investigated as function of developing stages, flow-rates and plasma power. The most important atomic and molecular components were identified and their evolution was studied as function of He flow-rate and plasma power towards understanding basic mechanisms occurring in this type of plasma. The characteristic temperatures (vibrational Tvibr, rotational Trot and excitation Texc) and the electron number density (ne) were determined.

  17. Formation of hydrocarbons on Titan: Impact of rapid association reactions at low pressure

    NASA Astrophysics Data System (ADS)

    Vuitton, V.; Yelle, R. V.; Lavvas, P.; Klippenstein, S. J.

    2011-10-01

    In the 1980's, Voyager revealed that complex organic molecules were present in Titan's atmosphere but the actual mechanisms leading to this rich chemistry were largely unknown. The recent Cassini results indicate that the chemistry ocurring in Titan's upper atmosphere is far more complex than anticipated. The detection of heavy positive and negative ions [13] reveals that much of the molecular growth occurs in the upper atmosphere rather than at lower altitudes [5, 12]. Photochemical models predict that three-body association reactions (A + B + M!AB + M) are the main production route for several hydrocarbons, including alkanes [2, 3]. The kinetic parameters of these reactions strongly depend on density and are therefore extremely difficult to constrain by experimental measurements as the low pressure of Titan's upper atmosphere cannot be reproduced in the laboratory. As a consequence, they have to be extrapolated outside the range of measurements, leading to high uncertainties. According to these extrapolations, three-body association reactions are only efficient in Titan's lower atmosphere. However, radiative association reactions (A + B ! AB + h) do not depend on pressure and can therefore still be efficient in the upper atmosphere. Unfortunately, they are largely uncharacterized and have consequently been neglected in photochemical models so far. Because of their potential importance at higher altitude, association reactions can have an important contribution to our understanding of molecular growth and better constraints for them are required. In the recent years, theoretical calculations of kinetics parameters have become more and more reliable [7]. We therefore performed ab initio transition state theory based master equation calculations for several radical-radical and radical-molecule association reactions. The computed kinetics parameters were included in our photochemical model of Titan. We present here the main results and discuss their impact for the

  18. The treatment of Staphyloccocus aureus infected sore nipples: a randomized comparative study.

    PubMed

    Livingstone, V; Stringer, L J

    1999-09-01

    Sore, cracked nipples are commonly experienced by breastfeeding mothers. We have previously reported a strong correlation between sore, cracked nipples and S. aureus colonization. A prospective, randomized clinical trial was performed to compare four treatment regimes for S. aureus infected sore nipples. Eighty-four breastfeeding mothers were enrolled in the study. After 5 days to 7 days of treatment, only 8% of mothers showed improvement in the "optimal breastfeeding technique alone" group, 16% improved with topical mupiricin, 29% improved with topical fusidic acid, yet 79% improved with oral antibiotics (p < .0001). Optimal breastfeeding techniques and topical antibiotics ointment failed to heal most infected, sore, cracked nipples. Mastitis developed in 12% to 35% of mothers not treated with systemic antibiotics compared to 5% of mothers treated with systemic antibiotics (p < .005). In conclusion, S. aureus infected sore, cracked nipples should be diagnosed as a potentially widespread impetigo vulgaris and treated aggressively with systemic antibiotics in order to improve healing and decrease the risk of developing mastitis due to an ascending lactiferous duct bacterial infection.

  19. Ketorolac Tromethamine Spray Prevents Postendotracheal-Intubation-Induced Sore Throat after General Anesthesia

    PubMed Central

    Yang, H. L.; Tsai, S. C.; Tsay, P. K.; Lin, H. T.

    2016-01-01

    Background. Postoperative sore throat is one of the major complaints of general anesthesia in the postanesthesia care unit. This prospective study investigated the preventive effect of ketorolac tromethamine spray in postendotracheal-intubation-induced sore throat after general anesthesia. Methods. Surgical patients undergoing general anesthesia with endotracheal intubation were recruited from a medical center. Patients were randomly assigned to group K (treated with 5% ketorolac tromethamine spray) or group D (treated with distilled water spray). Before intubation, each endotracheal tube was sprayed with the appropriate solution by physicians over the 20 cm length of the cuff. Each group comprised 95 patients fitting the inclusion and exclusion criteria for whom complete data sets were collected. The intensity of the sore throat was measured at 1, 3, 6, and 24 h after surgery, and data were compared. Results. The two groups had similar characteristics. Postoperative sore throat was significantly less frequent in group K than in group D (p < 0.001) and the pain intensity was significantly lower in group K than in group D at each time point (all p < 0.001). Conclusions. This study demonstrated that preanesthesia 5% ketorolac tromethamine spray could effectively decrease postendotracheal-intubation-induced sore throat in patients undergoing general anesthesia. PMID:28025646

  20. Three dimensional simulations of pattern formation during high-pressure, freely localized microwave breakdown in air

    SciTech Connect

    Kourtzanidis, K. Boeuf, J. P.; Rogier, F.

    2014-12-15

    Recent experiments have demonstrated that a freely localized 100 GHz microwave discharge can propagate towards the microwave source with high speed, forming a complex pattern of self-organized filaments. We present three-dimensional simulations of the formation and propagation of such patterns that reveal more information on their nature and interaction with the electromagnetic waves. The developed three-dimensional Maxwell-plasma solver permits the study of different forms of incident field polarization. Results for linear and circular polarization of the wave are presented and comparisons with recent experiments show a good overall agreement. The three dimensional simulations provide a quantitative analysis of the parameters controlling the time and length scales of the strongly non-linear plasma dynamics and could be useful for potential microwave plasma applications such as aerodynamic flow and combustion control.

  1. Dynamics of plasma expansion and shockwave formation in femtosecond laser-ablated aluminum plumes in argon gas at atmospheric pressures

    SciTech Connect

    Miloshevsky, Alexander; Harilal, Sivanandan S.; Miloshevsky, Gennady Hassanein, Ahmed

    2014-04-15

    Plasma expansion with shockwave formation during laser ablation of materials in a background gasses is a complex process. The spatial and temporal evolution of pressure, temperature, density, and velocity fields is needed for its complete understanding. We have studied the expansion of femtosecond (fs) laser-ablated aluminum (Al) plumes in Argon (Ar) gas at 0.5 and 1 atmosphere (atm). The expansion of the plume is investigated experimentally using shadowgraphy and fast-gated imaging. The computational fluid dynamics (CFD) modeling is also carried out. The position of the shock front measured by shadowgraphy and fast-gated imaging is then compared to that obtained from the CFD modeling. The results from the three methods are found to be in good agreement, especially during the initial stage of plasma expansion. The computed time- and space-resolved fields of gas-dynamic parameters have provided valuable insights into the dynamics of plasma expansion and shockwave formation in fs-pulse ablated Al plumes in Ar gas at 0.5 and 1 atm. These results are compared to our previous data on nanosecond (ns) laser ablation of Al [S. S. Harilal et al., Phys. Plasmas 19, 083504 (2012)]. It is observed that both fs and ns plumes acquire a nearly spherical shape at the end of expansion in Ar gas at 1 atm. However, due to significantly lower pulse energy of the fs laser (5 mJ) compared to pulse energy of the ns laser (100 mJ) used in our studies, the values of pressure, temperature, mass density, and velocity are found to be smaller in the fs laser plume, and their time evolution occurs much faster on the same time scale. The oscillatory shock waves clearly visible in the ns plume are not observed in the internal region of the fs plume. These experimental and computational results provide a quantitative understanding of plasma expansion and shockwave formation in fs-pulse and ns-pulse laser ablated Al plumes in an ambient gas at atmospheric pressures.

  2. Under pressure: quenching star formation in low-mass satellite galaxies via stripping

    NASA Astrophysics Data System (ADS)

    Fillingham, Sean P.; Cooper, Michael C.; Pace, Andrew B.; Boylan-Kolchin, Michael; Bullock, James S.; Garrison-Kimmel, Shea; Wheeler, Coral

    2016-12-01

    Recent studies of galaxies in the local Universe, including those in the Local Group, find that the efficiency of environmental (or satellite) quenching increases dramatically at satellite stellar masses below ˜108 M⊙. This suggest a physical scale where quenching transitions from a slow `starvation' mode to a rapid `stripping' mode at low masses. We investigate the plausibility of this scenario using observed H I surface density profiles for a sample of 66 nearby galaxies as inputs to analytic calculations of ram-pressure and turbulent viscous stripping. Across a broad range of host properties, we find that stripping becomes increasingly effective at M* ≲ 108 - 9 M⊙, reproducing the critical mass scale observed. However, for canonical values of the circumgalactic medium density (nhalo < 10-3.5 cm-3), we find that stripping is not fully effective; infalling satellites are, on average, stripped of only ≲ 40-60 per cent of their cold gas reservoir, which is insufficient to match observations. By including a host halo gas distribution that is clumpy and therefore contains regions of higher density, we are able to reproduce the observed H I gas fractions (and thus the high quenched fraction and short quenching time-scale) of Local Group satellites, suggesting that a host halo with clumpy gas may be crucial for quenching low-mass systems in Local Group-like (and more massive) host haloes.

  3. Formation of hydroxyl and water layers on MgO films studied with ambient pressure XPS

    NASA Astrophysics Data System (ADS)

    Newberg, John T.; Starr, David E.; Yamamoto, Susumu; Kaya, Sarp; Kendelewicz, Tom; Mysak, Erin R.; Porsgaard, Soeren; Salmeron, Miquel B.; Brown, Gordon E., Jr.; Nilsson, Anders; Bluhm, Hendrik

    2011-01-01

    To understand the interaction of water with MgO(100), a detailed quantitative assessment of the interfacial chemistry is necessary. We have used ambient pressure X-ray photoelectron spectroscopy (XPS) to measure molecular (H 2O) and dissociative (OH) water adsorption on a 4 monolayer (ML) thick MgO(100)/Ag(100) film under ambient conditions. Since the entire 4 ML metal oxide (Ox) film is probed by XPS, the reaction of the MgO film with water can be quantitatively studied. Using a multilayer model (Model 1) that measures changes in Ox thickness from O 1s (film) and Ag 3d (substrate) spectra, it is shown that the oxide portion of the MgO film becomes thinner upon hydroxylation. A reaction mechanism is postulated in which the top-most layer of MgO converts to Mg(OH) 2 upon dissociation of water. Based on this mechanism a second model (Model 2) is developed to calculate Ox and OH thickness changes based on OH/Ox intensity ratios from O 1s spectra measured in situ, with the known initial Ox thickness prior to hydroxylation. Models 1 and 2 are applied to a 0.15 Torr isobar experiment, yielding similar results for H 2O, OH and Ox thickness changes as a function of relative humidity.

  4. Formation of Hydroxyl and Water Layers on MgO Films Studied with Ambient Pressure XPS

    SciTech Connect

    Newberg, J.T.; Starr, D.; Yamamoto, S.; Kaya, S.; Kendelewicz, T.; Mysak, E.R.; Porsgaard, S.; Salmeron, M.B.; Brown Jr., G.E.; Nilsson, A.; Bluhm, H.

    2011-01-01

    To understand the interaction of water with MgO(100), a detailed quantitative assessment of the interfacial chemistry is necessary. We have used ambient pressure X-ray photoelectron spectroscopy (XPS) to measure molecular (H{sub 2}O) and dissociative (OH) water adsorption on a 4 monolayer (ML) thick MgO(100)/Ag(100) film under ambient conditions. Since the entire 4 ML metal oxide (Ox) film is probed by XPS, the reaction of the MgO film with water can be quantitatively studied. Using a multilayer model (Model 1) that measures changes in Ox thickness from O 1s (film) and Ag 3d (substrate) spectra, it is shown that the oxide portion of the MgO film becomes thinner upon hydroxylation. A reaction mechanism is postulated in which the top-most layer of MgO converts to Mg(OH)2 upon dissociation of water. Based on this mechanism a second model (Model 2) is developed to calculate Ox and OH thickness changes based on OH/Ox intensity ratios from O 1s spectra measured in situ, with the known initial Ox thickness prior to hydroxylation. Models 1 and 2 are applied to a 0.15 Torr isobar experiment, yielding similar results for H{sub 2}O, OH and Ox thickness changes as a function of relative humidity.

  5. Prophylactic Effects of Sauna on Delayed-Onset Muscle Soreness of the Wrist Extensors

    PubMed Central

    Khamwong, Peanchai; Paungmali, Aatit; Pirunsan, Ubon; Joseph, Leonard

    2015-01-01

    Background: High-intensity of exercise or unaccustomed eccentric exercise can cause the phenomenon of Exercise-Induced Muscle Damage (EIMD) which usually results in cramps, muscle strain, impaired muscle function and delayed-onset muscle soreness. Objectives: This study investigated the prophylactic effects of sauna towards the symptoms associated with muscle damage from eccentric exercises of wrist extensor muscle group. Patients and Methods: A total of twenty-eight subjects (mean age 20.9 years old, SD = 1.6) were randomly divided into the sauna group (n = 14) and the control group (n = 14). In the sauna group, subjects received sauna before eccentric exercise of the wrist extensor. The eccentric exercises were conducted on the non-dominant arm by using an isokinetic dynamometer. Pain Intensity (PI), Pressure Pain Threshold (PPT) and passive range of motion of wrist flexion (PF-ROM) and extension (PE-ROM) were measured as pain variables. Grip Strength (GS) and Wrist Extension Strength (WES) were measured as variables of wrist extensor muscle function. All the measurements were performed at baseline, immediately after and from 1st to 8th days after the exercise-induced muscle damage. Results: The sauna group significantly demonstrated a lower deficit in ROM (passive flexion and passive extension), GS and WES following exercise than that of the control group (P < 0.05). Conclusions: Sauna application prior to the exercise-induced muscle damage demonstrated effectiveness in reduction of sensory impairment (PF-ROM and PE-ROM) and improvement of muscle functions (GS, and WES) in wrist extensor muscle group. PMID:26446307

  6. Influence of vibration on delayed onset of muscle soreness following eccentric exercise

    PubMed Central

    Bakhtiary, Amir H; Safavi‐Farokhi, Ziaeddin; Aminian‐Far, Atefeh

    2007-01-01

    Delayed onset muscle soreness (DOMS), which may occur after eccentric exercise, may cause some reduction in ability in sport activities. For this reason, several studies have been designed on preventing and controlling DOMS. As vibration training (VT) may improve muscle performance, we designed this study to investigate the effect of VT on controlling and preventing DOMS after eccentric exercise. Methods Fifty healthy non‐athletic volunteers were assigned randomly into two experimental, VT (n = 25) and non‐VT (n = 25) groups. A vibrator was used to apply 50 Hz vibration on the left and right quadriceps, hamstring and calf muscles for 1 min in the VT group, while no vibration was applied in the non‐VT group. Then, both groups walked downhill on a 10° declined treadmill at a speed of 4 km/hour. The measurements included the isometric maximum voluntary contraction force (IMVC) of left and right quadriceps muscles, pressure pain threshold (PPT) 5, 10 and 15 cm above the patella and mid‐line of the calf muscles of both lower limbs before and the day after treadmill walking. After 24 hours, the serum levels of creatine‐kinase (CK), and DOMS level by visual analogue scale were measured. Results The results showed decreased IMVC force (P = 0.006), reduced PPT (P = 0.0001) and significantly increased mean of DOMS and CK levels in the non‐VT group, compared to the VT group (P = 0.001). Conclusion A comparison by experimental groups indicates that VT before eccentric exercise may prevent and control DOMS. Further studies should be undertaken to ascertain the stability and effectiveness of VT in athletics. PMID:17138635

  7. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

    NASA Astrophysics Data System (ADS)

    Ohtomo, Y.; Ijiri, A.; Ikegawa, Y.; Tsutsumi, M.; Imachi, H.; Uramoto, G.; Hoshino, T.; Morono, Y.; Tanikawa, W.; Hirose, T.; Inagaki, F.

    2013-12-01

    The geological CO2 sequestration into subsurface unmineable oil/gas fields and coal formations has been considered as one of the possible ways to reduce dispersal of anthropogenic greenhouse gasses into the atmosphere. However, feasibility of CO2 injection largely depends on a variety of geological and economical settings, and its ecological consequences have remained largely unpredictable. To address these issues, we developed a new flow-through-type CO2 injection system designated as the 'geobio-reactor system' to examine possible geophysical, geochemical and microbiological impact caused by CO2 injection under in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. In this study, we investigated Eocene bituminous coal-sandstones in the northwestern Pacific coast, Hokkaido, Japan, using the geobio-reactor system. Anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 mL/min, respectively) were continuously supplemented into the coal-sand column under the pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. Molecular analysis of bacterial 16S rRNA genes showed that predominant bacterial components were physically dispersed from coal to sand as the intact form during experiment. Cultivation experiments from sub-sampling fluids indicated that some terrestrial microbes could preserve their survival in subsurface condition. Molecular analysis of archaeal 16S rRNA genes also showed that no methanogens were activated during experiment. We also anaerobically incubated the coal sample using conventional batch-type cultivation technique with a medium for methanogens. After one year of the batch incubation at 20°C, methane could be detected from the cultures except for the acetate-fed culture. The sequence of archaeal 16S rRNA genes via PCR amplification obtained from the H2 plus formate-fed culture was affiliated with a hydrogenotrophic methanogen within the genus Methanobacterium, whereas the methanol plus trimethylamine culture

  8. Acute thoracic aortic dissection presenting as sore throat: report of a case.

    PubMed Central

    Liu, Wen-Pin; Ng, Kim-Choy

    2004-01-01

    Acute dissection of the aorta can be one of the most dramatic of cardiovascular emergencies. Its symptoms can occur abruptly and progress rapidly. Prompt recognition and appropriate intervention is crucial. However, not all aortic dissections present with classic symptoms of abrupt chest, back, or abdominal pain, and the diagnosis may be missed. Aortic dissection presenting as a sore throat is quite unusual. A 53-year-old man presented with sore throat as the early symptom of an acute thoracic aortic dissection. Unfortunately, the diagnosis was delayed, and the patient died. Given the high morbidity and mortality after delayed recognition or misdiagnosis, aortic dissection should be considered in the differential diagnosis of a patient presenting with sore throat and normal findings of neck and throat, even when there is no classic symptoms. PMID:15829145

  9. Pain and soreness associated with a percutaneous electrical stimulation muscle cramping protocol.

    PubMed

    Miller, Kevin C; Knight, Kenneth L

    2007-11-01

    Muscle cramps are difficult to study scientifically because of their spontaneity and unpredictability. Various laboratory techniques to induce muscle cramps have been explored but the best technique for inducing cramps is unclear. Electrical stimulation appears to be the most reliable, but there is a perception that it is extremely painful. Data to support this perception are lacking. We hypothesized that electrical stimulation is a tolerable method of inducing cramps with few side effects. We measured cramp frequency (HZ), pain during electrical stimulation, and soreness before, at 5 s, and 30, 60, and 90 min after cramp induction using a 100-mm visual analog scale. Group 1 received tibial nerve stimulation on 5 consecutive days; Group 2 received it on alternate days for five total treatments. Pain and soreness were mild. The highest ratings occurred on Day 1 and decreased thereafter. Intersession reliability was high. Our study showed that electrical stimulation causes little pain or soreness and is a reliable method for inducing cramps.

  10. An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation.

    PubMed

    Gorbanev, Yury; Soriano, Robert; O'Connell, Deborah; Chechik, Victor

    2016-11-03

    Non-thermal atmospheric pressure ('cold') plasmas have received increased attention in recent years due to their significant biomedical potential. The reactions of cold plasma with the surrounding atmosphere yield a variety of reactive species, which can define its effectiveness. While efficient development of cold plasma therapy requires kinetic models, model benchmarking needs empirical data. Experimental studies of the source of reactive species detected in aqueous solutions exposed to plasma are still scarce. Biomedical plasma is often operated with He or Ar feed gas, and a specific interest lies in investigation of the reactive species generated by plasma with various gas admixtures (O2, N2, air, H2O vapor, etc.) Such investigations are very complex due to difficulties in controlling the ambient atmosphere in contact with the plasma effluent. In this work, we addressed common issues of 'high' voltage kHz frequency driven plasma jet experimental studies. A reactor was developed allowing the exclusion of ambient atmosphere from the plasma-liquid system. The system thus comprised the feed gas with admixtures and the components of the liquid sample. This controlled atmosphere allowed the investigation of the source of the reactive oxygen species induced in aqueous solutions by He-water vapor plasma. The use of isotopically labelled water allowed distinguishing between the species originating in the gas phase and those formed in the liquid. The plasma equipment was contained inside a Faraday cage to eliminate possible influence of any external field. The setup is versatile and can aid in further understanding the cold plasma-liquid interactions chemistry.

  11. An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation

    PubMed Central

    Gorbanev, Yury; Soriano, Robert; O'Connell, Deborah; Chechik, Victor

    2016-01-01

    Non-thermal atmospheric pressure ('cold') plasmas have received increased attention in recent years due to their significant biomedical potential. The reactions of cold plasma with the surrounding atmosphere yield a variety of reactive species, which can define its effectiveness. While efficient development of cold plasma therapy requires kinetic models, model benchmarking needs empirical data. Experimental studies of the source of reactive species detected in aqueous solutions exposed to plasma are still scarce. Biomedical plasma is often operated with He or Ar feed gas, and a specific interest lies in investigation of the reactive species generated by plasma with various gas admixtures (O2, N2, air, H2O vapor, etc.) Such investigations are very complex due to difficulties in controlling the ambient atmosphere in contact with the plasma effluent. In this work, we addressed common issues of 'high' voltage kHz frequency driven plasma jet experimental studies. A reactor was developed allowing the exclusion of ambient atmosphere from the plasma-liquid system. The system thus comprised the feed gas with admixtures and the components of the liquid sample. This controlled atmosphere allowed the investigation of the source of the reactive oxygen species induced in aqueous solutions by He-water vapor plasma. The use of isotopically labelled water allowed distinguishing between the species originating in the gas phase and those formed in the liquid. The plasma equipment was contained inside a Faraday cage to eliminate possible influence of any external field. The setup is versatile and can aid in further understanding the cold plasma-liquid interactions chemistry. PMID:27842375

  12. Analysis of formation pressure test results in the Mount Elbert methane hydrate reservoir through numerical simulation

    USGS Publications Warehouse

    Kurihara, M.; Sato, A.; Funatsu, K.; Ouchi, H.; Masuda, Y.; Narita, H.; Collett, T.S.

    2011-01-01

    Targeting the methane hydrate (MH) bearing units C and D at the Mount Elbert prospect on the Alaska North Slope, four MDT (Modular Dynamic Formation Tester) tests were conducted in February 2007. The C2 MDT test was selected for history matching simulation in the MH Simulator Code Comparison Study. Through history matching simulation, the physical and chemical properties of the unit C were adjusted, which suggested the most likely reservoir properties of this unit. Based on these properties thus tuned, the numerical models replicating "Mount Elbert C2 zone like reservoir" "PBU L-Pad like reservoir" and "PBU L-Pad down dip like reservoir" were constructed. The long term production performances of wells in these reservoirs were then forecasted assuming the MH dissociation and production by the methods of depressurization, combination of depressurization and wellbore heating, and hot water huff and puff. The predicted cumulative gas production ranges from 2.16??106m3/well to 8.22??108m3/well depending mainly on the initial temperature of the reservoir and on the production method.This paper describes the details of modeling and history matching simulation. This paper also presents the results of the examinations on the effects of reservoir properties on MH dissociation and production performances under the application of the depressurization and thermal methods. ?? 2010 Elsevier Ltd.

  13. Effects of the homeopathic remedy arnica on attenuating symptoms of exercise-induced muscle soreness

    PubMed Central

    Plezbert, Julie A.; Burke, Jeanmarie R.

    2005-01-01

    Abstract Objective To evaluate the clinical efficacy of Arnica at a high potency (200c), on moderating delayed onset muscle soreness and accompanying symptoms of muscle dysfunction. Methods Twenty subjects completed a maximal eccentric exercise protocol with the non-dominate elbow flexors to induce delayed onset muscle soreness. Either Arnica or placebo tablets were administered in a random, double- blinded fashion immediately after exercise and at 24 hours and 72 hours after exercise. Before exercise, immediately post-exercise, and at 24, 48, 72, and 96 hours post-exercise, assessments of delayed onset muscle soreness and muscle function included: 1) muscle soreness and functional impairment; 2) maximum voluntary contraction torque; 3) muscle swelling; and 4) range of motion tests to document spontaneous muscle shortening and muscle shortening ability. Blood samples drawn before exercise and at 24, 48, and 96 hours after exercise were used to measure muscle enzymes as indirect indices of muscle damage. Results Regardless of the intervention, the extent of delayed onset muscle soreness and elevations in muscle enzymes were similar on the days following the eccentric exercise protocol. The post-exercise time profiles of decreases in maximum voluntary contraction torque and muscle shortening ability and increases in muscle swelling and spontaneous muscle shortening were similar for each treatment intervention. Conclusions The results of this study did not substantiate the clinical efficacy of Arnica at a high potency on moderating delayed onset muscle soreness and accompanying symptoms of muscle dysfunction. Despite the findings of this study, future investigations on the clinical efficacy of homeopathic interventions should consider incorporating research strategies that emphasize differential therapeutics for each patient rather than treating a specific disease or symptom complex, such as DOMS, with a single homeopathic remedy. PMID:19674657

  14. Initial stages of oxide formation on the Zr surface at low oxygen pressure: An in situ FIM and XPS study

    PubMed Central

    Bespalov, I.; Datler, M.; Buhr, S.; Drachsel, W.; Rupprechter, G.; Suchorski, Y.

    2015-01-01

    An improved methodology of the Zr specimen preparation was developed which allows fabrication of stable Zr nanotips suitable for FIM and AP applications. Initial oxidation of the Zr surface was studied on a Zr nanotip by FIM and on a polycrystalline Zr foil by XPS, both at low oxygen pressure (10−8–10−7 mbar). The XPS data reveal that in a first, fast stage of oxidation, a Zr suboxide interlayer is formed which contains three suboxide components (Zr+1, Zr+2 and Zr+3) and is located between the Zr surface and a stoichiometric ZrO2 overlayer that grows in a second, slow oxidation stage. The sole suboxide layer has been observed for the first time at very early states of the oxidation (oxygen exposure ≤4 L). The Ne+ FIM observations are in accord with a two stage process of Zr oxide formation. PMID:25766998

  15. Mechanisms of a novel anticancer therapeutic strategy involving atmospheric pressure plasma-mediated apoptosis and DNA strand break formation.

    PubMed

    Chung, Woo-Hyun

    2016-01-01

    Atmospheric pressure plasma has been developed for a variety of biomedical applications due to its chemically reactive components. Recently, the plasma has emerged as a promising novel cancer therapy based on its ability to selectively ablate cancer cells while leaving normal cells essentially unaffected. The therapeutic effect of plasma is attributed to intracellular generation of reactive oxygen/nitrogen species (ROS/RNS) leading to mitochondria-mediated apoptosis and to activation of the DNA damage checkpoint signaling pathway via severe DNA strand break formation. However, the biochemical mechanisms responsible for appropriate activation of these physiological events and which pathway is more crucial for plasma-mediated cytotoxicity have not been clarified. Understanding the molecular link between ROS/RNS-mediated apoptosis and DNA damage-involved chromosome instability is critical for the development of more efficacious therapeutic strategies for selective killing of diverse cancer cells.

  16. Studies on the tempo of bubble formation in recently cavitated vessels: a model to predict the pressure of air bubbles.

    PubMed

    Wang, Yujie; Pan, Ruihua; Tyree, Melvin T

    2015-06-01

    A cavitation event in a vessel replaces water with a mixture of water vapor and air. A quantitative theory is presented to argue that the tempo of filling of vessels with air has two phases: a fast process that extracts air from stem tissue adjacent to the cavitated vessels (less than 10 s) and a slow phase that extracts air from the atmosphere outside the stem (more than 10 h). A model was designed to estimate how water tension (T) near recently cavitated vessels causes bubbles in embolized vessels to expand or contract as T increases or decreases, respectively. The model also predicts that the hydraulic conductivity of a stem will increase as bubbles collapse. The pressure of air bubbles trapped in vessels of a stem can be predicted from the model based on fitting curves of hydraulic conductivity versus T. The model was validated using data from six stem segments each of Acer mono and the clonal hybrid Populus 84 K (Populus alba × Populus glandulosa). The model was fitted to results with root mean square error less than 3%. The model provided new insight into the study of embolism formation in stem tissue and helped quantify the bubble pressure immediately after the fast process referred to above.

  17. Modification of polypropylene foils by low pressure oxygen plasma and its influence on the formation of titanium dioxide films

    NASA Astrophysics Data System (ADS)

    Sadowski, Rafal; Macyk, Wojciech

    2014-10-01

    Commercially available polypropylene foils were pre-treated with low pressure, room temperature radio frequency (RF) oxygen plasma at constant power and pressure. Various durations of pre-treatment process were applied. Afterwards the samples were covered with titanium dioxide thin film by dip-coating technique and photosensitized by titanium(IV) surface complexes formed upon impregnation with catechol-like ligands. Optical emission spectroscopy (OES) measurements were used for determining plasma species. The surface properties before and after plasma treatment were characterized by contact angle measurements, FTIR-ATR, UV-Vis, and X-ray photoelectron spectroscopy (XPS). Titanium dioxide thin films were characterized by scanning electron microscopy (SEM) and UV-Vis spectroscopy. The photoactivity of TiO2 films was tested by photocurrent measurements. It was shown that plasma pre-treatment is essential for oxygen groups formation which contribute to titanium dioxide binding to polymer surface. The support from National Science Centre within the DEC-2012/05/N/ST5/01497 grant is highly acknowledged.

  18. The Role of Carbides in Formation of Surface Layer on Steel X153CrMoV12 Due to Low-Pressure Nitriding (Vacuum Nitriding)

    NASA Astrophysics Data System (ADS)

    Januszewicz, B.; Wołowiec, E.; Kula, P.

    2015-05-01

    The mechanism of formation of surface layer on steel X153CrMoV12 in the process of vacuum nitriding (low-pressure nitriding) in a universal vacuum furnace in an atmosphere of dissociated ammonia at a pressure of 30 × 102 Pa (30 mbar) is studied by the methods of light microscopy and measurement of microhardness. The chemical composition of the nitrided layers is determined.

  19. Interleukin-6 and Delayed Onset Muscle Soreness Do Not Vary during the Menstrual Cycle

    ERIC Educational Resources Information Center

    Chaffin, Morgan E.; Berg, Kris E.; Meendering, Jessica R.; Llewellyn, Tamra L.; French, Jeffrey A.; Davis, Jeremy E.

    2011-01-01

    The purpose of this study was to determine if a difference in interleukin-6 (IL-6) and delayed onset muscles soreness (DOMS) exists in two different phases of the menstrual cycle. Nine runners performed one 75-min high-intensity interval running session during the early follicular (EF) phase and once during the midluteal (ML) phase of the…

  20. The experience of a sore mouth and associated symptoms in patients with cancer receiving outpatient chemotherapy.

    PubMed

    Brown, Carlton G; McGuire, Deborah B; Peterson, Douglas E; Beck, Susan L; Dudley, William N; Mooney, Kathleen H

    2009-01-01

    This study aimed to describe sore mouth (SM) severity and distress, associated symptoms, and consequences in cancer chemotherapy outpatients. Secondary analysis was used in this study. A total of 223 patients in 4 treatment centers participated in the study. Data from an intervention study using a computer-based telephone communication system to assess patients' daily symptom experience were analyzed to obtain highest, average, and lowest ratings of severity and distress for SM, fatigue, trouble sleeping, feeling down/blue, and feeling anxious. Consequence data included oral intake, time spent lying down, ability to work, and daily activity. Approximately 51% reported SM, with a mean highest, average, and lowest severity score of 3.1 in cycle 2 and 3.09 in cycle 3. Sore mouth severity was correlated with severity of fatigue, feeling down/blue, feeling anxious, and trouble sleeping. Sore mouth distress was correlated with the same symptoms. Sore mouth severity was correlated with the number of 8-oz glasses of liquid consumed, effect on daily activity, time spent lying down, but not with ability to work. Half of patients experienced SM, which was associated with several other symptoms and led to specific consequences. Understanding the complex symptom experience of patients with SM, including consequences, will assist nurses in developing more comprehensive clinical assessments and interventions. In addition, the association of multiple symptoms with SM will provide a foundation for further research investigation in oral mucositis.

  1. Effects of whole-body vibration after eccentric exercise on muscle soreness and muscle strength recovery.

    PubMed

    Timon, Rafael; Tejero, Javier; Brazo-Sayavera, Javier; Crespo, Carmen; Olcina, Guillermo

    2016-06-01

    [Purpose] The aim of this study was to investigate whether or not a single whole-body vibration treatment after eccentric exercise can reduce muscle soreness and enhance muscle recovery. [Subjects and Methods] Twenty untrained participants were randomly assigned to two groups: a vibration group (n=10) and control group (n=10). Participants performed eccentric quadriceps training of 4 sets of 5 repetitions at 120% 1RM, with 4 min rest between sets. After that, the vibration group received 3 sets of 1 min whole body vibration (12 Hz, 4 mm) with 30 s of passive recovery between sets. Serum creatine kinase, blood urea nitrogen, muscle soreness (visual analog scale) and muscle strength (peak isometric torque) were assessed. [Results] Creatine kinase was lower in the vibration group than in the control group at 24 h (200.2 ± 8.2 vs. 300.5 ± 26.1 U/L) and at 48 h (175.2 ± 12.5 vs. 285.2 ± 19.7 U/L) post-exercise. Muscle soreness decreased in vibration group compared to control group at 48 h post-exercise (34.1 ± 11.4 vs. 65.2 ± 13.2 mm). [Conclusion] Single whole-body vibration treatment after eccentric exercise reduced delayed onset muscle soreness but it did not affect muscle strength recovery.

  2. Effects of Varying Recovery Periods on Muscle Enzymes, Soreness, and Performance in Baseball Pitchers

    PubMed Central

    Potteiger, Jeffrey A.; Blessing, Daniel L.; Wilson, G. Dennis

    1992-01-01

    In this study we examined the effects of varied recovery time on serum creatine kinase (CK), serum lactate dehydrogenase (LDH), muscle soreness, and pitch velocity in baseball pitchers. Ten males who had pitching experience participated in the study. After an 18-day training period, subjects pitched three simulated games. Game A and Game B were separated by four days of rest, while Game B and Game C were separated by two days of rest. CK, LDH, and muscle soreness were evaluated at the following times: before and immediately after exercise, and six, 24, 48, and 72 hours after exercise. Muscle performance was evaluated by measuring pitch velocity during the games. The CK level was elevated after each game (Game A - 249 U/l; Game B - 243 U/l; and Game C - 240 U/l); then it dropped toward baseline (p≤0.01). CK post-exercise values were not different among games A, B, and C. LDH displayed a response similar to CK; however, there was a reduction over the span of the games (p≤0.05). Muscle soreness was significantly elevated immediately after exercise (p≤0.01) compared to all other measurement times. Pitch velocity was not different among games A, B, and C. Results indicate that muscle damage, as evidenced by CK release, occurs in response to baseball pitching. However CK values, muscle soreness, and pitch velocity are not significantly affected by changes in the amount of recovery time typically scheduled between games. PMID:16558126

  3. Effect of Whirlpool Therapy on the Signs and Symptoms of Delayed-Onset Muscle Soreness

    PubMed Central

    Kuligowski, Lori A.; Lephart, Scott M.; Giannantonio, Frank P.; Blanc, Rob O.

    1998-01-01

    Objective: To determine the efficacy of warm whirlpool, cold whirlpool, and contrast therapy in the treatment of delayed-onset muscle soreness. Design and Setting: Subjects performed eccentric contractions of the elbow flexors and received 4 treatments: immediately postexercise and 24, 48, and 72 hours postexercise. Treatments consisted of 24-minute treatments with warm whirlpool, cold whirlpool, contrast therapy, or no treatment. Subjects: Fifty-six sex-matched volunteers from the University of Pittsburgh. Measurements: Measurements were taken at 5 assessment times: pre-exercise (0 hours); prior to treatment at 24, 48, and 72 hours postexercise; and at 96 hours postexercise. Dependent variables were degrees of resting elbow flexion, active elbow flexion, and extension; perceived soreness values on a Graphic Pain Rating Scale; and maximal voluntary isometric contraction. A repeated-measures analysis of variance (group by time) and Tukey post hoc analysis were used to determine which treatment groups differed significantly in returning subjects to pre-exercise values. Results: Cold whirlpool and contrast therapy were found to return subjects to baseline values of resting elbow flexion and perceived soreness significantly more than warm whirlpool or no treatment (P < .01). Additionally, warm whirlpool was found to be more effective than no treatment in the return of resting elbow flexion (P < .01). Conclusions: These results suggest that cold whirlpool and contrast therapy are more effective than warm whirlpool or no treatment in alleviating delayed-onset muscle soreness in the elbow flexors. PMID:16558514

  4. Effects of whole-body vibration after eccentric exercise on muscle soreness and muscle strength recovery

    PubMed Central

    Timon, Rafael; Tejero, Javier; Brazo-Sayavera, Javier; Crespo, Carmen; Olcina, Guillermo

    2016-01-01

    [Purpose] The aim of this study was to investigate whether or not a single whole-body vibration treatment after eccentric exercise can reduce muscle soreness and enhance muscle recovery. [Subjects and Methods] Twenty untrained participants were randomly assigned to two groups: a vibration group (n=10) and control group (n=10). Participants performed eccentric quadriceps training of 4 sets of 5 repetitions at 120% 1RM, with 4 min rest between sets. After that, the vibration group received 3 sets of 1 min whole body vibration (12 Hz, 4 mm) with 30 s of passive recovery between sets. Serum creatine kinase, blood urea nitrogen, muscle soreness (visual analog scale) and muscle strength (peak isometric torque) were assessed. [Results] Creatine kinase was lower in the vibration group than in the control group at 24 h (200.2 ± 8.2 vs. 300.5 ± 26.1 U/L) and at 48 h (175.2 ± 12.5 vs. 285.2 ± 19.7 U/L) post-exercise. Muscle soreness decreased in vibration group compared to control group at 48 h post-exercise (34.1 ± 11.4 vs. 65.2 ± 13.2 mm). [Conclusion] Single whole-body vibration treatment after eccentric exercise reduced delayed onset muscle soreness but it did not affect muscle strength recovery. PMID:27390415

  5. Neutrophilia and an Anti-Inflammatory Drug as Markers of Inflammation in Delayed Muscle Soreness.

    ERIC Educational Resources Information Center

    Smith, Lucille L.; And Others

    This study reexamined the concept that delayed muscle soreness (DMS) is a form of inflammatory pain. This was accomplished by having 32 male volunteers perform exercise known to induce DMS and then assess the total and differential white blood cell changes. In addition, an anti-inflammatory drug, idomethacin, was administered to determine whether…

  6. Formation of As-As Interlayer Bonding in the collapsed tetragonal phase of NaFe2As2 under pressure

    PubMed Central

    Stavrou, Elissaios; Chen, Xiao-Jia; Oganov, Artem R.; Wang, A. F.; Yan, Y. J.; Luo, X. G.; Chen, X. H.; Goncharov, Alexander F.

    2015-01-01

    NaFe2As2 is investigated experimentally using powder x-ray diffraction and Raman spectroscopy at pressures up to 23 GPa at room temperature and using ab-initio calculations. The results reveal a pressure-induced structural modification at 4 GPa from the starting tetragonal to a collapsed tetragonal phase. We determined the changes in interatomic distances under pressure that allowed us to connect the structural changes and superconductivity. The transition is related to the formation of interlayer As-As bonds at the expense of weakening of Fe-As bonds in agreement with recent theoretical predictions. PMID:26014105

  7. Effect of Negative Pressure on Proliferation, Virulence Factor Secretion, Biofilm Formation, and Virulence-Regulated Gene Expression of Pseudomonas aeruginosa In Vitro

    PubMed Central

    Wang, Guo-Qi; Li, Tong-Tong; Li, Zhi-Rui; Zhang, Li-Cheng

    2016-01-01

    Objective. To investigate the effect of negative pressure conditions induced by NPWT on P. aeruginosa. Methods. P. aeruginosa was cultured in a Luria–Bertani medium at negative pressure of −125 mmHg for 24 h in the experimental group and at atmospheric pressure in the control group. The diameters of the colonies of P. aeruginosa were measured after 24 h. ELISA kit, orcinol method, and elastin-Congo red assay were used to quantify the virulence factors. Biofilm formation was observed by staining with Alexa Fluor® 647 conjugate of concanavalin A (Con A). Virulence-regulated genes were determined by quantitative RT-PCR. Results. As compared with the control group, growth of P. aeruginosa was inhibited by negative pressure. The colony size under negative pressure was significantly smaller in the experimental group than that in the controls (p < 0.01). Besides, reductions in the total amount of virulence factors were observed in the negative pressure group, including exotoxin A, rhamnolipid, and elastase. RT-PCR results revealed a significant inhibition in the expression level of virulence-regulated genes. Conclusion. Negative pressure could significantly inhibit the growth of P. aeruginosa. It led to a decrease in the virulence factor secretion, biofilm formation, and a reduction in the expression level of virulence-regulated genes. PMID:28074188

  8. The pressure is on: midwives and decubitus ulcers.

    PubMed

    Prior, Jenny

    2002-05-01

    Research regarding pressure area care and management in nursing extends back many years, but remains relevant and cited today. With relevant knowledge, midwives can help prevent the development of pressure sores in the maternity setting. Clinical governance and risk management should ensure that the incidence and occurrence of pressure sores in the midwifery arena is reported and fed into appropriate audit analysis at local, regional and national levels. Midwives need to seriously consider the implications of modern midwifery care and management in relation to the development of pressure sores in our population. Labour suite, high dependency, ward and community areas should include guidelines for the prevention, treatment and management of pressure sores, including mattress policies. Prophylactic measures and assessment scores could be incorporated into partogram documentation in the labour suite and as part of postoperative documentation in the ward environment for women who have undergone caesarean section. Trusts may find that a link midwife liasing with tissue viability nurses proves beneficial. Community midwives should forge links with the district nursing services in their Primary Care Trust areas with regard to developing or adapting tools. Knowledge of pathophysiology, prophylaxis and subsequent management of decubitus ulcers in maternity care is sadly lacking in midwifery textbooks. Future authors and editors should include this subject and it should feature more prominently in midwifery education curricula. It is clear that there is much work to be done in this area, both educationally and clinically. Further research is required to evaluate pressure prevention strategies in the midwifery arena, including the increasing provision of one-to-one care in labour suite units. Improvements in the appropriate prevention and subsequent treatment and management of pressure sores will benefit women and help save the NHS hundreds of thousands of pounds in treatment

  9. Immediate and short-term effects of the combination of dry needling and percutaneous TENS on post-needling soreness in patients with chronic myofascial neck pain

    PubMed Central

    León-Hernández, Jose V.; Martín-Pintado-Zugasti, Aitor; Frutos, Laura G.; Alguacil-Diego, Isabel M.; de la Llave-Rincón, Ana I.; Fernandez-Carnero, Josue

    2016-01-01

    ABSTRACT Background Dry needling (DN) and percutaneous electrical nerve stimulation (PENS) are widely used techniques in the treatment of myofascial pain. Objective To investigate the immediate and short-term effects of the combination of DN and PENS compared to DN alone on the upper trapezius muscle. Method This is a 72-hour follow-up single-blinded randomized controlled trial. Sixty-two volunteer patients with chronic myofascial neck pain with active Myofascial Trigger Points (MTrPs) in the upper trapezius muscle were recruited. Randomization was performed, and 31 patients received DN treatment (DN group) and 31 received DN and PENS (DN+PENS group). The primary outcomes were neck disability index (NDI) and visual analog scale for pain for both post-needling soreness (PNS) and neck pain intensity (NPI). Pressure pain threshold (PPT) and cervical range of motion (CROM) were the secondary outcomes. Results We detected between-group differences in NPI and PNS in favor of the DN+PENS group immediately after treatment. No between-group differences in NDI were observed. Conclusion PENS application after dry needling treatment is more effective than dry needling alone for decreasing soreness in the short term and improving neck pain intensity immediately in patients with myofascial chronic neck pain. PMID:27410163

  10. Multi-wavelength studies of spectacular ram-pressure stripping of a galaxy. II. Star formation in the tail

    SciTech Connect

    Yagi, Masafumi; Gu, Liyi; Nakazawa, Kazuhiro; Makishima, Kazuo; Fujita, Yutaka; Akahori, Takuya; Hattori, Takashi; Yoshida, Michitoshi

    2013-12-01

    With multiband photometric data in public archives, we detected four intracluster star-forming regions in the Virgo Cluster. Two of them were at a projected distance of 35 kpc from NGC 4388 and the other two were 66 kpc away. Our new spectroscopic observations revealed that their recessional velocities were comparable to the ram-pressure-stripped tail of NGC 4388 and confirmed the association. The stellar mass of the star-forming regions ranged from 10{sup 4} to 10{sup 4.5} M {sub ☉} except for that of the faintest one, which was <10{sup 3} M {sub ☉}. The metallicity was comparable to a solar abundance and the age of the stars was ∼10{sup 6.8} yr. Their young stellar age meant that the star formation should have started after the gas was stripped from NGC 4388. This implied in situ condensation of the stripped gas. We also found that two star-forming regions were located near the leading edge of a filamentary dark cloud. The extinction of the filament was smaller than that derived from the Balmer decrement of the star-forming regions, implying that the dust in the filament would be locally dense around the star-forming regions.

  11. Electron ranaway and ion-ion plasma formation in afterglow low-pressure plasma of oxygen-containing gas mixtures

    NASA Astrophysics Data System (ADS)

    Kudryavtsev, Anatoly; Bogdanov, Eugene; Kosykh, Nikolay; Gutsev, Sergey

    2012-10-01

    Experimental investigation of temporal evolution of charged plasma species in afterglow plasma of oxygen-containing mixtures have been investigated. The probe VAC and the time dependence of the saturation positive and negative particles currents to a probe in a fixed bias voltage were performed. The decay of afterglow low-pressure electronegative gas plasmas take place in two distinct stages (the electron-ion stage, and the ion-ion stage) as it was shown in [1] for pure oxygen. In the first stage, the negative ions are locked within a discharge volume and plasma is depleted of electrons and positive ions. The electron density decay is faster, than exponential, and practically all electrons leave plasma volume during finite time followed by the ion--ion (electron-free) plasma formation. The decay of the ion-ion plasma depends on the presence of detachment. With a large content of electronegative gas (oxygen) in a mixture, when there is a ``detachment particles,'' a small fraction of the electrons appearing as a result of the detachment continue to hold all negative ions in the discharge volume. In this case, the densities of all charged plasma components decay according to the same exponential law with a characteristic detachment time. At a low oxygen content in the gas mixture there is no detachment and plasma decays by an ion--ion ambipolar diffusion mechanism.[4pt][1]. S.A.Gutsev, A.A.Kudryavtsev, V.A.Romanenko. Tech.Phys. 40, 1131, (1995).

  12. Partitioning of Pd Between Fe-S-C and Mantle Liquids at High Pressure and Temperature: Implications for Core Formation

    NASA Technical Reports Server (NTRS)

    Righter, K.; Humayun, M.; Danielson, L.

    2007-01-01

    One of the most elusive geochemical aspects of the early Earth has been explaining the near chondritic relative abundances of the highly siderophile elements (HSE; Au, Re and the platinum group elements) in Earth's primitive upper mantle (PUM). Perhaps they were delivered to the Earth after core formation, by late addition of carbonaceous chondrite material. However, the recognition that many moderately siderophile elements can be explained by high pressure and temperature (PT) metal-silicate equilibrium, leads to the question whether high PT equilibrium can also explain the HSE concentrations. Answers to this question have been slowed by experimental difficulties (nugget effect and very low solubilities). But two different perspectives have emerged from recent studies. One perspective is that D(M/S) for HSE at high PT are not low enough to explain terrestrial mantle depletions of these elements (for Pd and Pt). A second perspective is D(M/S) are reduced substantially at high PT and even low enough to explain terrestrial mantle depletions (for Au and Pt). Issues complicating interpretation of all experiments include use of MgO- and FeO-free silicate melts, and S-free and FeNi metal-free systems. In addition, conclusions for Pt rest on an interpretation that the tiny metallic nuggets plaguing many such experiments, were formed upon quench. There is not agreement on this issue, and the general question of HSE solubility at high PT remains unresolved

  13. Effects of Massage on Delayed-Onset Muscle Soreness, Swelling, and Recovery of Muscle Function

    PubMed Central

    Zainuddin, Zainal; Newton, Mike; Sacco, Paul; Nosaka, Kazunori

    2005-01-01

    Context: Delayed-onset muscle soreness (DOMS) describes muscle pain and tenderness that typically develop several hours postexercise and consist of predominantly eccentric muscle actions, especially if the exercise is unfamiliar. Although DOMS is likely a symptom of eccentric-exercise–induced muscle damage, it does not necessarily reflect muscle damage. Some prophylactic or therapeutic modalities may be effective only for alleviating DOMS, whereas others may enhance recovery of muscle function without affecting DOMS. Objective: To test the hypothesis that massage applied after eccentric exercise would effectively alleviate DOMS without affecting muscle function. Design: We used an arm-to-arm comparison model with 2 independent variables (control and massage) and 6 dependent variables (maximal isometric and isokinetic voluntary strength, range of motion, upper arm circumference, plasma creatine kinase activity, and muscle soreness). A 2-way repeated-measures analysis of variance and paired t tests were used to examine differences in changes of the dependent variable over time (before, immediately and 30 minutes after exercise, and 1, 2, 3, 4, 7, 10, and 14 days postexercise) between control and massage conditions. Setting: University laboratory. Patients or Other Participants: Ten healthy subjects (5 men and 5 women) with no history of upper arm injury and no experience in resistance training. Intervention(s): Subjects performed 10 sets of 6 maximal isokinetic (90°·s−1) eccentric actions of the elbow flexors with each arm on a dynamometer, separated by 2 weeks. One arm received 10 minutes of massage 3 hours after eccentric exercise; the contralateral arm received no treatment. Main Outcome Measure(s): Maximal voluntary isometric and isokinetic elbow flexor strength, range of motion, upper arm circumference, plasma creatine kinase activity, and muscle soreness. Results: Delayed-onset muscle soreness was significantly less for the massage condition for peak

  14. Thermal decomposition of gaseous ammonium nitrate at low pressure: kinetic modeling of product formation and heterogeneous decomposition of nitric acid.

    PubMed

    Park, J; Lin, M C

    2009-12-03

    The thermal decomposition of ammonium nitrate, NH(4)NO(3) (AN), in the gas phase has been studied at 423-56 K by pyrolysis/mass spectrometry under low-pressure conditions using a Saalfeld reactor coated with boric acid. The sublimation of NH(4)NO(3) at 423 K was proposed to produce equal amounts of NH(3) and HNO(3), followed by the decomposition reaction of HNO(3), HNO(3) + M --> OH + NO(2) + M (where M = third-body and reactor surface). The absolute yields of N(2), N(2)O, H(2)O, and NH(3), which can be unambiguously measured and quantitatively calibrated under a constant pressure at 5-6.2 torr He are kinetically modeled using the detailed [H,N,O]-mechanism established earlier for the simulation of NH(3)-NO(2) (Park, J.; Lin, M. C. Technologies and Combustion for a Clean Environment. Proc. 4th Int. Conf. 1997, 34-1, 1-5) and ADN decomposition reactions (Park, J.; Chakraborty, D.; Lin, M. C. Proc. Combust. Inst. 1998, 27, 2351-2357). Since the homogeneous decomposition reaction of HNO(3) itself was found to be too slow to account for the consumption of reactants and the formation of products, we also introduced the heterogeneous decomposition of HNO(3) in our kinetic modeling. The heterogeneous decomposition rate of HNO(3), HNO(3) + (B(2)O(3)/SiO(2)) --> OH + NO(2) + (B(2)O(3)/SiO(2)), was determined by varying its rate to match the modeled result to the measured concentrations of NH(3) and H(2)O; the rate could be represented by k(2b) = 7.91 x 10(7) exp(-12 600/T) s(-1), which appears to be consistent with those reported by Johnston and co-workers (Johnston, H. S.; Foering, L.; Tao, Y.-S.; Messerly, G. H. J. Am. Chem. Soc. 1951, 73, 2319-2321) for HNO(3) decomposition on glass reactors at higher temperatures. Notably, the concentration profiles of all species measured could be satisfactorily predicted by the existing [H,N,O]-mechanism with the heterogeneous initiation process.

  15. Thermal Decomposition of Gaseous Ammonium Nitrate at Low Pressure: Kinetic Modeling of Product Formation and Heterogeneous Decomposition of Nitric Acid

    NASA Astrophysics Data System (ADS)

    Park, J.; Lin, M. C.

    2009-10-01

    The thermal decomposition of ammonium nitrate, NH4NO3 (AN), in the gas phase has been studied at 423-56 K by pyrolysis/mass spectrometry under low-pressure conditions using a Saalfeld reactor coated with boric acid. The sublimation of NH4NO3 at 423 K was proposed to produce equal amounts of NH3 and HNO3, followed by the decomposition reaction of HNO3, HNO3 + M → OH + NO2 + M (where M = third-body and reactor surface). The absolute yields of N2, N2O, H2O, and NH3, which can be unambiguously measured and quantitatively calibrated under a constant pressure at 5-6.2 torr He are kinetically modeled using the detailed [H,N,O]-mechanism established earlier for the simulation of NH3-NO2 (Park, J.; Lin, M. C. Technologies and Combustion for a Clean Environment. Proc. 4th Int. Conf. 1997, 34-1, 1-5) and ADN decomposition reactions (Park, J.; Chakraborty, D.; Lin, M. C. Proc. Combust. Inst. 1998, 27, 2351-2357). Since the homogeneous decomposition reaction of HNO3 itself was found to be too slow to account for the consumption of reactants and the formation of products, we also introduced the heterogeneous decomposition of HNO3 in our kinetic modeling. The heterogeneous decomposition rate of HNO3, HNO3 + (B2O3/SiO2) → OH + NO2 + (B2O3/SiO2), was determined by varying its rate to match the modeled result to the measured concentrations of NH3 and H2O; the rate could be represented by k2b = 7.91 × 107 exp(-12 600/T) s-1, which appears to be consistent with those reported by Johnston and co-workers (Johnston, H. S.; Foering, L.; Tao, Y.-S.; Messerly, G. H. J. Am. Chem. Soc. 1951, 73, 2319-2321) for HNO3 decomposition on glass reactors at higher temperatures. Notably, the concentration profiles of all species measured could be satisfactorily predicted by the existing [H,N,O]-mechanism with the heterogeneous initiation process.

  16. Optimal heating condition of mouthguard sheet in vacuum-pressure formation: part 2 Olefin-based thermoplastic elastomer.

    PubMed

    Takahashi, Mutsumi; Koide, Kaoru

    2016-04-01

    The purposes of this study were to clarify the suitable heating conditions during vacuum-pressure formation of olefin copolymer sheets and to examine the sheet temperature at molding and the thickness of the molded mouthguard. Mouthguards were fabricated using 4.0-mm-thick olefin copolymer sheets utilizing a vacuum-pressure forming device, and then, 10 s of vacuum forming and 2 min of compression molding were applied. Three heating conditions were investigated. They were, defined by the degree of sagging observed at the center of the softened sheet (10, 15, or 20 mm lower than the clamp (H-10, H-15, or H-20, respectively)). The working model was trimmed to the height of 20 mm at the maxillary central incisor and 15 mm at the mesiobuccal cusp of the maxillary first molar. The temperature on both the directly heated and the non-heated surfaces of the mouthguard sheet was measured by the radiation thermometer for each condition. The thickness of mouthguard sheets after fabrication was determined for the incisal portion (incisal edge and labial surface) and molar portion (cusp and buccal surface), and dimensional measurements were obtained using a measuring device. Differences in the thickness due to the heating condition of the sheets were analyzed by one-way analysis of variance and Bonferroni's multiple comparison tests. The temperature difference between the heated and non-heated surfaces was highest under H-10. Sheet temperature under H-15 and H-20 was almost the same. The thickness differences were noted at incisal edge, cusp, and buccal surface, and H-15 was the greatest. This study demonstrated that heating of the sheet resulting in sag of 15 mm or more was necessary for sufficient softening of the sheet and that the mouthguard thickness decreased with increased sag. In conclusion, sag of 15 mm can be recommended as a good indicator of appropriate molding timing for this material.

  17. The Effect of Warm-Up and Cool-Down Exercise on Delayed Onset Muscle Soreness in the Quadriceps Muscle: a Randomized Controlled Trial

    PubMed Central

    Olsen, Olav; Sjøhaug, Mona; van Beekvelt, Mireille; Mork, Paul Jarle

    2012-01-01

    The aim of the present study was to investigate the effect of warm-up and cool-down exercise on delayed onset of muscle soreness at the distal and central parts of rectus femoris following leg resistance exercise. Thirty-six volunteers (21 women, 15 men) were randomly assigned to the warm-up (20 min ergometer cycling prior to the resistance exercise), cool-down (20 min cycling after the resistance exercise), or control group performing resistance exercise only. The resistance exercise consisted of front lunges (10×5 repetitions/sets) with external loading of 40% (women) and 50% (men) of body mass. Primary outcomes were pressure pain threshold along rectus femoris and maximal isometric knee extension force. Data were recorded before the resistance exercise and on the two consecutive days. Pressure pain threshold at the central muscle belly was significantly reduced for the control group on both day 2 and 3 (p≤0.003) but not for the warm-up group (p≥0.21). For the cool-down group, pressure pain threshold at the central muscle belly was significantly reduced on day 2 (p≤0.005) and was also lower compared to the warm-up group (p=0.025). Force was significantly reduced on day 2 and 3 for all groups (p<0.001). This study indicates that aerobic warm-up exercise performed prior to resistance exercise may prevent muscle soreness at the central but not distal muscle regions, but it does not prevent loss of muscle force. PMID:23486850

  18. Application of Formation Testing While Drilling (GeoTap) for acquiring formation pressure data from the Azeri, Chirag and Guneshli wells which were drilled in the Khazarian-Caspian Sea of the Azerbaijan Republic

    NASA Astrophysics Data System (ADS)

    Amirov, Elnur

    2016-04-01

    A new technology to acquire wireline quality pressure tests using a Logging While Drilling approach has been successfully implemented few years ago in Azeri, Chirag and Guneshli wells which were drilled in the Khazarian-Caspian Sea of the Azerbaijan Republic. The Formation Tester While Drilling tool (GeoTap) uses a testing sequence similar to wireline tools. A single probe is extended to the borehole wall and a small pretest volume withdrawn from the formation. The resulting pressure transient is then analyzed for formation pressure, formation permeability and mobility information. Up-link and down-link capabilities have been added to achieve test control and quality feedback. An efficient downlink algorithm is used downhole to analyze the data. The parameters and pressure data are transmitted to the surface in real-time for continuous monitoring of the test. More detailed pressure data is recorded and retrieved after returning to surface. Use of a quartz gauge allows excellent accuracy. Azeri, Chirag and Guneshli fields consist of layered sand reservoirs alternation with shale sequences and detailed pressure data is acquired on a high percentage of wells in order to understand lateral and vertical continuity of different flow units. The formation tester can be utilized with the 'triple combo' Logging While Drilling string which eliminates the need to rig up wireline on many wells. Wireline formation tester runs are time consuming - particularly if high deviation or high overbalance conditions are encountered requiring pipe conveyed techniques. Non-Productive Time is high when the wireline tools are stuck and fishing operations are required. The Sperry Drilling GeoTap formation pressure tester service provides real-time formation pressure measurements. It bridges the critical gap between drilling safety and optimization, by providing early and reliable measurements of key reservoir properties, while improving reservoir understanding and completion design in real

  19. Dysphagia, dysphonia and sore throat following cerebral infarction: an unexpected cause.

    PubMed

    Slade, Peter Michael Edward; Larsen, Matthew Peter

    2015-07-06

    A 75-year-old woman presented with left-sided weakness. There was no speech disturbance or reported swallowing difficulties. CT of the head revealed infarction in the territory of the right middle cerebral artery. The patient was transferred to the acute stroke unit and a nasogastric tube was placed following a failed swallow screening test. The following day, on assessment, there was considerable pain on swallowing. The tone and quality of the patient's voice had deteriorated and there was significant dysphagia. Seven days later a plastic item, later identified as the patient's denture, was expectorated. Following this, the dysphagia, dysphonia and sore throat rapidly resolved. The case highlights the importance of considering foreign body in the differential, and oral cavity examination in the assessment of a patient with dysphagia and sore throat is essential.

  20. Grapevine species from varied native habitats exhibit differences in embolism formation/repair associated with leaf gas exchange and root pressure.

    PubMed

    Knipfer, Thorsten; Eustis, Ashley; Brodersen, Craig; Walker, Andrew M; McElrone, Andrew J

    2015-08-01

    Drought induces xylem embolism formation, but grapevines can refill non-functional vessels to restore transport capacity. It is unknown whether vulnerability to embolism formation and ability to repair differ among grapevine species. We analysed in vivo embolism formation and repair using x-ray computed microtomography in three wild grapevine species from varied native habitats (Vitis riparia, V. arizonica, V. champinii) and related responses to measurements of leaf gas exchange and root pressure. Vulnerability to embolism formation was greatest in V. riparia, intermediate in V. arizonica and lowest in V. champinii. After re-watering, embolism repair was rapid and pronounced in V. riparia and V. arizonica, but limited or negligible in V. champinii even after numerous days. Similarly, root pressure measured after re-watering was positively correlated with drought stress severity for V. riparia and V. arizonica (species exhibiting embolism repair) but not for V. champinii. Drought-induced reductions in transpiration were greatest for V. riparia and least in V. champinii. Recovery of transpiration after re-watering was delayed for all species, but was greatest for V. champinii and most rapid in V. arizonica. These species exhibit varied responses to drought stress that involve maintenance/recovery of xylem transport capacity coordinated with root pressure and gas exchange responses.

  1. Group A streptococcal sore throat in a periurban population of northern India: a one-year prospective study.

    PubMed Central

    Nandi, S.; Kumar, R.; Ray, P.; Vohra, H.; Ganguly, N. K.

    2001-01-01

    OBJECTIVE: To estimate the incidence and risk factors of group A streptococcus (GAS) sore throat among school-aged children living in a periurban slum area of Chandigarh, North India. METHODS: A total of 536 children aged 5-15 years from 261 families identified by a systematic random selection method were enrolled in the study. Episodes of sore throat were recorded through fortnightly home visits over a one-year period. The local vernacular (Hindi) terms gala kharab (bad throat) and khansi jukam (cough and cold) were used to identify symptoms of sore throat, and throat swab specimens were collected from children who had these symptoms on the day of the home visit. Bacterial culture was carried out and the isolation of GAS was confirmed using group-A-specific antiserum. FINDINGS: The incidences of sore throat and GAS sore throat were, respectively, 7.05 and 0.95 episodes per child-year. The incidence was higher in the following situations: among 11-year-olds, during the winter (November to January) and rainy (August) months (a bimodal peak), among children living in houses where there was no separate room for the kitchen, and in homes that included a tobacco smoker. CONCLUSION: The results show that the incidence of GAS sore throat was related to age, season, and indoor air pollution. PMID:11436474

  2. Effects of a non-steroidal anti-inflammatory drug on delayed onset muscle soreness and indices of damage.

    PubMed Central

    Donnelly, A E; McCormick, K; Maughan, R J; Whiting, P H; Clarkson, P M

    1988-01-01

    Twenty untrained male volunteers were required to run downhill for 45 minutes on a motor driven treadmill to induce muscle soreness. The volunteers took diclofenac or placebo before and for 72 hours after two runs 10 weeks apart, in a randomised double blind crossover design. Subjective soreness was assessed before and at intervals up to 72 hours after each run; venous blood samples, collected at the same time intervals, were used to estimate serum activities of creatine kinase, lactate dehydrogenase and aspartate aminotransferase and serum concentrations of creatinine and urea. Subjective soreness and the biochemical parameters increased after both runs, although the serum enzyme response to the second run was reduced. Diclofenac had no influence on the serum biochemical response to downhill running. Although overall soreness was not affected by diclofenac, individual soreness measurements were reduced by diclofenac at the first period of the study. These results suggest that diclofenac does not influence muscle damage, but may slightly reduce the associated soreness. PMID:3370401

  3. The Combined Effect of High Hydrostatic Pressure and Calcium Salts on the Stability, Solubility and Gel Formation of β-Lactoglobulin

    PubMed Central

    Saalfeld, Daniel; Riegel, Ina; Kulozik, Ulrich; Gebhardt, Ronald

    2015-01-01

    Stability, aggregation and gelation of β-Lactoglobulin are affected by high pressure and salts of the Hofmeister series. Little is known about their combined effects on structure formation processes of β-Lactoglobulin, mainly because many salts of the series are not suitable for use in food. Here, we investigate the effect of calcium salts on the strength of pressure-induced gels, inspired by the fact that high pressure and salts change the water structure in a similar way. We find that the larger the applied pressures, the higher the strength of the gels. In addition to pressure, there is a significant influence by the type of anions and the amount of added calcium salts. Gel strength increases in the order CaCl2 < Ca (NO3)2 < CaI2. This trend correlates with the position of the salts in the Hofmeister series. The results are explained by analogy with the thermal aggregate formation by taking reaction rates for unfolding and aggregation, as well as specific/non-specific salts effect into consideration. PMID:28231200

  4. The prophylactic effect of dexamethasone on postoperative sore throat in prone position surgery

    PubMed Central

    Lee, Sang Ho; Lee, Yoon Chan; Choi, So Ron; Lee, Seung-Cheol; Lee, Jong Hwan; Chung, Chan Jong

    2016-01-01

    Background Sore throat and hoarseness are common complications after general anesthesia with tracheal intubation. The position for patients can affect the incidence of postoperative sore throat (POST) by causing displacement of the endotracheal tube. This study investigated the prophylactic effect of dexamethasone in prone position surgeries. Methods One hundred-fifty patients undergoing lumbar spine surgery (18-75 yr) were randomly allocated into the normal saline group (group P, n = 50), dexamethasone 0.1 mg/kg group (group D1, n = 50) or dexamethasone 0.2 mg/kg group (group D2, n = 50). The incidence and severity of POST, hoarseness, and cough were measured using direct interview at 1, 6, and 24 h after tracheal extubation. The severity of POST, hoarseness, and cough were graded using a 4-point scale. Results At 1, 6, and 24 h after extubation, the incidence of sore throat was significantly lower in group D1 (1 h; P = 0.015, 6 h; P < 0.001, 24 h; P = 0.038) and group D2 (1 h; P < 0.001, 6 h; P < 0.001, 24 h; P = 0.017) compared to group P. There were less number of patients in the groups D1 and D2 than group P suffering from moderate grade of POST at 1, 24 h after extubation. The incidence of hoarseness at 1, 6, and 24 h after extubation was significantly lower in groups D2 than group P (P < 0.001). There were no significant differences in the incidence of cough among the three groups. Conclusions The prophylactic use of dexamethasone 0.1 mg/kg and 0.2 mg/kg in prone surgery reduces the incidence of postoperative sore throat and dexamethasone 0.2 mg/kg decreases the incidence of hoarseness. PMID:27274371

  5. Postexercise protein supplementation improves health and muscle soreness during basic military training in Marine recruits.

    PubMed

    Flakoll, Paul J; Judy, Tom; Flinn, Kim; Carr, Christopher; Flinn, Scott

    2004-03-01

    Elevated postexercise amino acid availability has been demonstrated to enhance muscle protein synthesis acutely, but the long-term impact of postexercise protein supplementation on variables such as health, muscle soreness, and function are unclear. Healthy male US Marine recruits from six platoons (US Marine Corps Base, Parris Island, SC; n = 387; 18.9 +/- 0.1 yr, 74.7 +/- 1.1 kg, 13.8 +/- 0.4% body fat) were randomly assigned to three treatments within each platoon. Nutrients supplemented immediately postexercise during the 54-day basic training were either placebo (0 g carbohydrate, 0 g protein, 0 g fat), control (8, 0, 3), or protein supplement (8, 10, 3). Subjects and observers making measurements and data analysis were blinded to subject groupings. Compared with placebo and control groups, the protein-supplemented group had an average of 33% fewer total medical visits, 28% fewer visits due to bacterial/viral infections, 37% fewer visits due to muscle/joint problems, and 83% fewer visits due to heat exhaustion. Recruits experiencing heat exhaustion had greater body mass, lean, fat, and water losses. Muscle soreness immediately postexercise was reduced by protein supplementation vs. placebo and control groups on both days 34 and 54. Postexercise protein supplementation may not only enhance muscle protein deposition but it also has significant potential to positively impact health, muscle soreness, and tissue hydration during prolonged intense exercise training, suggesting a potential therapeutic approach for the prevention of health problems in severely stressed exercising populations.

  6. The Affect on Delayed Onset Muscle Soreness Recovery for Ultrasound with Bee Venom

    PubMed Central

    Kim, Seung Kyun; Kim, Myung Chul

    2014-01-01

    [Purpose] The purpose of this study was to evaluate whether ultrasound alone or ultrasound with bee venom is effective in treating delayed onset muscle soreness of the biceps brachii muscle, using the visual analogue scale, range of motion test (flexion and extension), and serum creatine kinase level. [Subjects] Twenty women participated in this study. [Methods] Repeated eccentric contractions were used to induce delayed onset muscle soreness in the elbow flexor of the subjects. The subjects were randomized to be treated with ultrasound alone or ultrasound with bee venom. We evaluated the effects of treatments in the 2 groups. Individual subjects were assessed using the visual analogue scale, range of motion test, and serum creatine kinase level. The assessment parameters were evaluated 4 times: before exercise and 24, 48, and 72 hours after exercise. [Results] The visual analogue scale scores were significantly different before and after the experiment in both the group treated with ultrasound and the group treated with ultrasound and bee venom. The difference in elbow flexion and extension before and after the experiment was significantly different in both groups. No significant difference was found in the serum creatine kinase levels before and after the experiment. [Conclusion] Treatment with ultrasound and bee venom is effective for managing delayed onset muscle soreness. PMID:25276027

  7. The affect on delayed onset muscle soreness recovery for ultrasound with bee venom.

    PubMed

    Kim, Seung Kyun; Kim, Myung Chul

    2014-09-01

    [Purpose] The purpose of this study was to evaluate whether ultrasound alone or ultrasound with bee venom is effective in treating delayed onset muscle soreness of the biceps brachii muscle, using the visual analogue scale, range of motion test (flexion and extension), and serum creatine kinase level. [Subjects] Twenty women participated in this study. [Methods] Repeated eccentric contractions were used to induce delayed onset muscle soreness in the elbow flexor of the subjects. The subjects were randomized to be treated with ultrasound alone or ultrasound with bee venom. We evaluated the effects of treatments in the 2 groups. Individual subjects were assessed using the visual analogue scale, range of motion test, and serum creatine kinase level. The assessment parameters were evaluated 4 times: before exercise and 24, 48, and 72 hours after exercise. [Results] The visual analogue scale scores were significantly different before and after the experiment in both the group treated with ultrasound and the group treated with ultrasound and bee venom. The difference in elbow flexion and extension before and after the experiment was significantly different in both groups. No significant difference was found in the serum creatine kinase levels before and after the experiment. [Conclusion] Treatment with ultrasound and bee venom is effective for managing delayed onset muscle soreness.

  8. Microstructure development, compositional/physical gradient formation and related mechanical properties of gas-pressure-sintered silicon nitride ceramics

    NASA Astrophysics Data System (ADS)

    Tiegs, Terry Norman

    Three inter-related aspects in the fabrication of silicon nitride ceramics were performed for the thesis work. The topics included: (1) an analysis of the composition and physical gradients in bulk silicon nitride, (2) the effect of sintering parameters on microstructure development and the resulting mechanical properties, and (3) an investigation of ss-Sisb3Nsb4 nucleation and initial stage microstructure development. The composition and physical gradients in bulk silicon nitride are due to the furnace conditions and the environment adjacent to the samples. Loss of SiO from the exposed surfaces results in the formation of nitrogen-rich phases, such as melilite on the as-sintered surfaces. The high nitrogen concentration in the near-surface region promotes ss-Sisb3Nsb4 grain growth. Along with the compositional gradients, mechanical property differences also exist between the as-sintered surfaces and the bulk materials. For example, the strengths of as-sintered surfaces of Sisb3Nsb4-Ysb2Osb3-Alsb2Osb3 were observed to be reduced by more than 30% compared to the bulk material. Gas-pressure sintering (GPS) was used to densify silicon nitride two types of sintering additives: Sisb3Nsb4-6% Ysb2Osb3-2% Alsb2Osb3 and Sisb3Nsb4-Srsb2Lasb4Ybsb4(SiOsb4)sb6Osb2. For both compositions a lower densification temperature (1900sp°C in the present tests) was the most significant factor affecting the fracture toughness and promoting a bimodal grain structure. The low significance of the other process parameters implies the microstructure (and therefore properties) are essentially 'locked-in' during the densification stage. The kinetics of the alpha-to-ss Sisb3Nsb4 transformation are dependent on several characteristics of the starting silicon nitride powder. Most importantly, are the silicon nitride powder surface area and initial ss-Sisb3Nsb4 content which both tend to increase the transformation rate. Other factors, such as lattice oxygen or carbon contents, appear to contribute

  9. Effect of Caffeine on Perceived Soreness and Functionality Following an Endurance Cycling Event.

    PubMed

    Caldwell, Aaron R; Tucker, Matthew A; Butts, Cory L; McDermott, Brendon P; Vingren, Jakob L; Kunces, Laura J; Lee, Elaine C; Munoz, Colleen X; Williamson, Keith H; Armstrong, Lawrence E; Ganio, Matthew S

    2017-03-01

    Caldwell, AR, Tucker, MA, Butts, CL, McDermott, BP, Vingren, JL, Kunces, LJ, Lee, EC, Munoz, CX, Williamson, KH, Armstrong, LE, and Ganio, MS. Effect of caffeine on perceived soreness and functionality following an endurance cycling event. J Strength Cond Res 31(3): 638-643, 2017-Caffeine can reduce muscle pain during exercise; however, the efficacy of caffeine in improving muscle soreness and recovery from a demanding long-duration exercise bout has not been established. The purpose of this study was to investigate the effects of caffeine intake on ratings of perceived muscle soreness (RPMS) and perceived lower extremity functionality (LEF) following the completion of a 164-km endurance cycling event. Before and after cycling RPMS (1-to-6; 6 = severe soreness) and LEF (0-to-80; 80 = full functionality) were assessed by questionnaires. Subjects ingested 3 mg/kg body mass of caffeine or placebo pills in a randomized, double-blind fashion immediately after the ride and for the next 4 mornings (i.e., ∼800 hours) and 3 afternoons (i.e., ∼1200 hours). Before each ingestion, RPMS and LEF were assessed. Afternoon ratings of LEF were greater with caffeine ingestion the first day postride (65.0 ± 6.1 vs. 72.3 ± 6.7; for placebo and caffeine, respectively; p = 0.04), but at no other time points (p > 0.05). The caffeine group tended to have lower overall RPMS in the afternoon versus placebo (i.e., main effect of group; 1.1 ± 0.2 vs. 0.5 ± 0.2; p = 0.09). Afternoon RPMS for the legs was significantly lower in the caffeine group (main effect of caffeine; 1.3 ± 0.2 vs. 0.5 ± 0.3; p = 0.05). In conclusion, ingesting caffeine improved RPMS for the legs, but not LEF in the days following an endurance cycling event. Athletes may benefit from ingesting caffeine in the days following an arduous exercise bout to relieve feelings of soreness and reduced functionality.

  10. Pomegranate Supplementation Accelerates Recovery of Muscle Damage and Soreness and Inflammatory Markers after a Weightlifting Training Session

    PubMed Central

    Ammar, Achraf; Turki, Mouna; Chtourou, Hamdi; Hammouda, Omar; Trabelsi, Khaled; Kallel, Choumous; Abdelkarim, Osama; Hoekelmann, Anita; Bouaziz, Mohamed; Ayadi, Fatma; Driss, Tarak; Souissi, Nizar

    2016-01-01

    Purpose The aim of this study was to investigate the effect of natural Pomegranate juice supplementation on performance and acute and delayed responses of muscle soreness and biomarkers of muscle damage after a weightlifting training session. Methods Nine elite weightlifters (21±0.5 years) performed two Olympic-Weightlifting-sessions after either placebo (PLA) or natural pomegranate juice (POMj) supplementations. Heart rate, blood pressure and blood samples (hematological parameters, muscle damage and C-reactive protein (CRP)) were collected at rest, 3min and 48h after each session. Weightlifting performance, RPE, and DOMS were also assessed after each training session. Results T-test showed higher performance (+8.30%) and lower RPE values (-4.37%) using POMj supplementation (p<0.05) in comparison with PLA. For the DOMS values, a significant improvement (13.4%) was shown only for the knee extensors (p<0.01) using the POMj. Compared to PLA condition, POMj attenuated the acute (i.e., 3min) increase of systolic blood pressure (SBP), HR, CK and LDH (p<0.05; -4.46%, -1.81%, -8.75%, -1.64%, respectively) and blunted the significant increase of ASAT, PAL and CRP (p>0.05). Additionally, during the 48h following the training session, POMj improved the recovery kinetic of SBP (p<0.01, 7.97%), CK (p<0.001, 11.34%), LDH (p<0.05, 7.30%) and ASAT (p<0.05, 6.77%). Indeed, the present study showed that 48h of recovery associated to natural POMj supplementation was sufficient to reach the resting values of the selected muscle damage markers after intensive training session. Conclusion Natural POMj seems to ameliorate the capacity to adhere to an intensive training program. Therefore, elite weightlifters are advised to use natural POMj during intensive training program and competition to accelerate muscle recovery. Trial Registration ClinicalTrials.gov NCT02697903 PMID:27764091

  11. Formation pressure testing at the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Operational summary, history matching, and interpretations

    USGS Publications Warehouse

    Anderson, B.; Hancock, S.; Wilson, S.; Enger, C.; Collett, T.; Boswell, R.; Hunter, R.

    2011-01-01

    In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), and the U.S. Geological Survey, collected open-hole pressure-response data, as well as gas and water sample collection, in a gas hydrate reservoir (the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well) using Schlumberger's Modular Dynamics Formation Tester (MDT) wireline tool. Four such MDT tests, ranging from six to twelve hours duration, and including a series of flow, sampling, and shut-in periods of various durations, were conducted. Locations for the testing were selected based on NMR and other log data to assure sufficient isolation from reservoir boundaries and zones of excess free water. Test stages in which pressure was reduced sufficiently to mobilize free water in the formation (yet not cause gas hydrate dissociation) produced readily interpretable pressure build-up profiles. Build-ups following larger drawdowns consistently showed gas-hydrate dissociation and gas release (as confirmed by optical fluid analyzer data), as well as progressive dampening of reservoir pressure build-up during sequential tests at a given MDT test station.History matches of one multi-stage, 12-h test (the C2 test) were accomplished using five different reservoir simulators: CMG-STARS, HydrateResSim, MH21-HYDRES, STOMP-HYD, and TOUGH. +. HYDRATE. Simulations utilized detailed information collected across the reservoir either obtained or determined from geophysical well logs, including thickness (11.3. m, 37 ft.), porosity (35%), hydrate saturation (65%), both mobile and immobile water saturations, intrinsic permeability (1000 mD), pore water salinity (5 ppt), and formation temperature (3.3-3.9 ??C). This paper will present the approach and preliminary results of the history-matching efforts, including estimates of initial formation permeability and analyses of the various unique features exhibited by the MDT results. ?? 2010 Elsevier Ltd.

  12. Stretching Before and After Exercise: Effect on Muscle Soreness and Injury Risk

    PubMed Central

    Andersen, J. C

    2005-01-01

    Reference: Herbert RD, Gabriel M. Effects of stretching before and after exercise on muscle soreness and risk of injury: systematic review. BMJ. 2002;325:468. Clinical Question: Among physically active individuals, does stretching before and after exercise affect muscle soreness and risk of injury? Data Sources: Studies were identified by searching MEDLINE (1966–February 2000), EMBASE (1988–February 2000), CINAHL (1982–1999), SPORT Discus (1949–1999), and PEDro (to February 2000). I searched the reference lists of identified studies manually until no further studies were identified. The search terms stretch, exercise, warm-up, and cool down were used in all databases except MEDLINE. In MEDLINE, an optimized OVID search strategy was used. This strategy included the terms searched in the other databases as well as terms such as flexibility, athletic injuries, sports, soreness, and muscle. Study Selection: The search was limited to English-language articles obtained from the electronic searches and the subsequent manual searches. This review included randomized or quasirandomized investigations that studied the effects of any stretching technique, before or after exercise, on delayed-onset muscle soreness, risk of injury, or athletic performance. Studies were included only if stretching occurred immediately before or after exercising. Data Extraction: Data extraction and assessment of study quality were well described. The principal outcome measures were measurements of muscle soreness and indices of injury risk. Results from the soreness studies were pooled by converting the numeric scores to percentages of the maximum possible score. These data were then reported as millimeters on a 100-mm visual analogue scale. Results of comparable studies were pooled using a fixed-effects model meta-analysis. Survival analysis using a Cox regression model was calculated on the time-to-event (injury) data. Main Results: The total number of articles identified using the

  13. Effect of inlet-air humidity, temperature, pressure, and reference Mach number on the formation of oxides of nitrogen in a gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

    1973-01-01

    Tests were conducted to determine the effect of inlet air humidity on the formation of oxides of nitrogen (NOx) from a gas turbine combustor. Combustor inlet air temperature ranged from 506 K (450 F) to 838 K (1050 F). The tests were primarily run at a constant pressure of 6 atmospheres and reference Mach number of 0.065. The NOx emission index was found to decrease with increasing inlet air humidity at a constant exponential rate: NOx = NOx0e-19H (where H is the humidity and the subscript 0 denotes the value at zero humidity). the emission index increased exponentially with increasing normalized inlet air temperature to the 1.14 power. Additional tests made to determine the effect of pressure and reference Mach number on NOx showed that the NOx emission index varies directly with pressure to the 0.5 power and inversely with reference Mach number.

  14. [Comparative study between benzydamine hydrochloride gel, lidocaine 5% gel and lidocaine 10% spray on endotracheal tube cuff as regards postoperative sore throat].

    PubMed

    Mekhemar, Nashwa Abdallah; El-Agwany, Ahmed Samy; Radi, Wafaa Kamel; El-Hady, Sherif Mohammed

    2016-01-01

    Postoperative sore throat is a common complication after endotracheal intubation. After tracheal intubation, the incidence of sore throat varies from 14.4% to 50%. The aim of the study was to compare between benzydamine hydrochloride gel, lidocaine 5% gel and lidocaine 10% spray on the endotracheal tube cuff as regards postoperative sore throat. The present study was carried out on 124 patients admitted to Alexandria university hospitals for lumbar fixation surgery requiring general anesthesia. Patients were randomly allocated into 4 groups. Benzydamine hydrochloride gel, 5% lidocaine hydrochloride gel, 10% lidocaine hydrochloride spray, or normal saline were applied on endotracheal tube cuffs before endotracheal intubation. The patients were examined for sore throat (none, mild, moderate, or severe) at 0, 1, 6, 12, and 24h after extubation. The results were collected, analyzed and presented in table and figure. The highest incidence of postoperative sore throat occurred at 6h after extubation in all groups. There was a significantly lower incidence of postoperative sore throat in the benzydamine group than 5% lidocaine gel, 10% lidocaine spray, and normal saline groups. The benzydamine group had significantly decreased severity of postoperative sore throat compared with the 10% lidocaine, 5% lidocaine, and normal saline groups at observation time point. Compared with the 5% lidocaine the 10% lidocaine group had significantly increased incidence and severity of postoperative sore throat after extubation. Compared with normal saline the 10% lidocaine group had increased incidence of postoperative sore throat. There were no significant differences among groups in local or systemic side effects. So in conclusion, benzydamine hydrochloride gel on the endotracheal tube cuff is a simple and effective method to reduce the incidence and severity of postoperative sore throat. Application of 10% lidocaine spray should be avoided because of worsening of postoperative sore

  15. Comparative study between benzydamine hydrochloride gel, lidocaine 5% gel and lidocaine 10% spray on endotracheal tube cuff as regards postoperative sore throat.

    PubMed

    Mekhemar, Nashwa Abdallah; El-Agwany, Ahmed Samy; Radi, Wafaa Kamel; El-Hady, Sherif Mohammed

    2016-01-01

    Postoperative sore throat is a common complication after endotracheal intubation. After tracheal intubation, the incidence of sore throat varies from 14.4% to 50%. The aim of the study was to compare between benzydamine hydrochloride gel, lidocaine 5% gel and lidocaine 10% spray on the endotracheal tube cuff as regards postoperative sore throat. The present study was carried out on 124 patients admitted to Alexandria university hospitals for lumbar fixation surgery requiring general anesthesia. Patients were randomly allocated into 4 groups. Benzydamine hydrochloride gel, 5% lidocaine hydrochloride gel, 10% lidocaine hydrochloride spray, or normal saline were applied on endotracheal tube cuffs before endotracheal intubation. The patients were examined for sore throat (none, mild, moderate, or severe) at 0, 1, 6, 12, and 24h after extubation. The results were collected, analyzed and presented in table and figure. The highest incidence of postoperative sore throat occurred at 6h after extubation in all groups. There was a significantly lower incidence of postoperative sore throat in the benzydamine group than 5% lidocaine gel, 10% lidocaine spray, and normal saline groups. The benzydamine group had significantly decreased severity of postoperative sore throat compared with the 10% lidocaine, 5% lidocaine, and normal saline groups at observation time point. Compared with the 5% lidocaine the 10% lidocaine group had significantly increased incidence and severity of postoperative sore throat after extubation. Compared with normal saline the 10% lidocaine group had increased incidence of postoperative sore throat. There were no significant differences among groups in local or systemic side effects. So in conclusion, benzydamine hydrochloride gel on the endotracheal tube cuff is a simple and effective method to reduce the incidence and severity of postoperative sore throat. Application of 10% lidocaine spray should be avoided because of worsening of postoperative sore

  16. A Differential Pressure Laminar Flow Reactor Supports Osteogenic Differentiation and Extracellular Matrix Formation from Adipose Mesenchymal Stem Cells in a Macroporous Ceramic Scaffold

    PubMed Central

    Kasper, Cornelia; Israelowitz, Meir; Gille, Christoph; von Schroeder, Herbert P.; Reimers, Kerstin; Vogt, Peter M.

    2012-01-01

    Abstract We present a laminar flow reactor for bone tissue engineering that was developed based on a computational fluid dynamics model. The bioreactor design permits a laminar flow field through its specific internal shape. An integrated bypass system that prevents pressure build-up through bypass openings for pressure release allows for a constant pressure environment during the changing of permeability values that are caused by cellular growth within a porous scaffold. A macroporous ceramic scaffold, composed of zirconium dioxide, was used as a test biomaterial that studies adipose stem cell behavior within a controlled three-dimensional (3D) flow and pressure environment. The topographic structure of the material provided a basis for stem cell proliferation and differentiation toward the osteogenic lineage. Dynamic culture conditions in the bioreactor supported cell viability during long-term culture and induced cell cluster formation and extra-cellular matrix deposition within the porous scaffold, though no complete closure of the pores with new-formed tissue was observed. We postulate that our system is suitable for studying fluid shear stress effects on stem cell proliferation and differentiation toward bone formation in tissue-engineered 3D constructs. PMID:23515420

  17. A high-pressure premixed flat-flame burner for chemical process studies. [of pollutant formation in hydrocarbon flames

    NASA Technical Reports Server (NTRS)

    Miller, I. M.

    1978-01-01

    A premixed flat-flame burner was designed and tested with methane-air mixtures at pressures from 1.1 to 20 atm and equivalence ratios from 0.7 to 1.1. Reactant velocity in the burner mixing chamber was used to characterize the range of stable flames at each pressure-equivalence-ratio condition. Color photographs of the flames were used to determine flame zone thickness and flame height. The results show that this burner can be used for chemical process studies in premixed high pressure methane-air flames up to 20 atm.

  18. Season-long increases in perceived muscle soreness in professional rugby league players: role of player position, match characteristics and playing surface.

    PubMed

    Fletcher, Ben D; Twist, Craig; Haigh, Julian D; Brewer, Clive; Morton, James P; Close, Graeme L

    2016-01-01

    Rugby League (RL) is a high-impact collision sport characterised by repeated sprints and numerous high-speed impacts and consequently players often report immediate and prolonged muscle soreness in the days after a match. We examined muscle soreness after matches during a full season to understand the extent to which match characteristics influence soreness. Thirty-one elite Super League players provided daily measures of muscle soreness after each of the 26 competitive fixtures of the 2012 season. Playing position, phase of the season, playing surface and match characteristics were recorded from each match. Muscle soreness peaked at day 1 and was still apparent at day 4 post-game with no attenuation in the magnitude of muscle soreness over the course of the season. Neither playing position, phase of season or playing surface had any effects on the extent of muscle soreness. Playing time and total number of collisions were significantly correlated with higher ratings of muscle soreness, especially in the forwards. These data indicate the absence "contact adaptations" in elite rugby players with soreness present throughout the entire season. Strategies must now be implemented to deal with the physical and psychological consequences of prolonged feeling of pain.

  19. The gaseous enthalpy of formation of the ionic liquid 1-butyl-3-methylimidazolium dicyanamide from combustion calorimetry, vapor pressure measurements, and ab initio calculations.

    PubMed

    Emel'yanenko, Vladimir N; Verevkin, Sergey P; Heintz, Andreas

    2007-04-04

    Ionic liquids are attracting growing interest as alternatives to conventional molecular solvents. Experimental values of vapor pressure, enthalpy of vaporization, and enthalpy of formation of ionic liquids are the key thermodynamic quantities, which are required for the validation and development of the molecular modeling and ab initio methods toward this new class of solvents. In this work, the molar enthalpy of formation of the liquid 1-butyl-3-methylimidazolium dicyanamide, 206.2 +/- 2.5 kJ.mol-1, was measured by means of combustion calorimetry. The molar enthalpy of vaporization of 1-butyl-3-methylimidazolium dicyanamide, 157.2 +/- 1.1 kJ.mol-1, was obtained from the temperature dependence of the vapor pressure measured using the transpiration method. The latter method has been checked with measurements of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide, where data are available from the effusion technique. The first experimental determination of the gaseous enthalpy of formation of the ionic liquid 1-butyl-3-methylimidazolium dicyanamide, 363.4 +/- 2.7 kJ.mol-1, from thermochemical measurements (combustion and transpiration) is presented. Ab initio calculations of the enthalpy of formation in the gaseous phase have been performed for 1-butyl-3-methylimidazolium dicyanamide using the G3MP2 theory. Excellent agreement with experimental results has been observed. The method developed opens a new way to obtain thermodynamic properties of ionic liquids which have not been available so far.

  20. Maximal force, voluntary activation and muscle soreness after eccentric damage to human elbow flexor muscles.

    PubMed

    Prasartwuth, O; Taylor, J L; Gandevia, S C

    2005-08-15

    Muscle damage reduces voluntary force after eccentric exercise but impaired neural drive to the muscle may also contribute. To determine whether the delayed-onset muscle soreness, which develops approximately 1 day after exercise, reduces voluntary activation and to identify the possible site for any reduction, voluntary activation of elbow flexor muscles was examined with both motor cortex and motor nerve stimulation. We measured maximal voluntary isometric torque (MVC), twitch torque, muscle soreness and voluntary activation in eight subjects before, immediately after, 2 h after, 1, 2, 4 and 8 days after eccentric exercise. Motor nerve stimulation and motor cortex stimulation were used to derive twitch torques and measures of voluntary activation. Eccentric exercise immediately reduced the MVC by 38 +/- 3% (mean +/- s.d., n = 8). The resting twitch produced by motor nerve stimulation fell by 82 +/- 6%, and the estimated resting twitch by cortical stimulation fell by 47 +/- 15%. While voluntary torque recovered after 8 days, both measures of the resting twitch remained depressed. Muscle tenderness occurred 1-2 days after exercise, and pain during contractions on days 1-4, but changes in voluntary activation did not follow this time course. Voluntary activation assessed with nerve stimulation fell 19 +/- 6% immediately after exercise but was not different from control values after 2 days. Voluntary activation assessed by motor cortex stimulation was unchanged by eccentric exercise. During MVCs, absolute increments in torque evoked by nerve and cortical stimulation behaved differently. Those to cortical stimulation decreased whereas those to nerve stimulation tended to increase. These findings suggest that reduced voluntary activation contributes to the early force loss after eccentric exercise, but that it is not due to muscle soreness. The impairment of voluntary activation to nerve stimulation but not motor cortical stimulation suggests that the activation

  1. Supplementation with a polyphenolic blend improves post-exercise strength recovery and muscle soreness

    PubMed Central

    Herrlinger, Kelli A.; Chirouzes, Diana M.; Ceddia, Michael A.

    2015-01-01

    Background Exercise can initiate a cascade of inflammatory and oxidative stress–related events leading to delayed onset muscle soreness. Polyphenols possess antioxidant and anti-inflammatory properties. Objective The current study examined the effects of a proprietary polyphenolic blend (PB), containing catechins and theaflavins, on exercise performance and recovery following an eccentric exercise challenge. Design Male participants (18–35 years of age) received placebo or PB at a low dose (PB-L, 1,000 mg/d) or high dose (PB-H, 2,000 mg/d) for 13 weeks. During the 13th week of supplementation, participants completed an eccentric exercise (40 min downhill treadmill run) followed by a strength assessment (peak torque on isokinetic leg extensions) pre-exercise, and 24, 48, and 96 h post-exercise. Muscle soreness (subjective questionnaire), markers of muscle stress (cortisol and creatine phosphokinase [CK]), and antioxidant capacity (ferric reducing ability of plasma [FRAP]) were also assessed. Results PB-H attenuated the decrease in peak torque observed in the placebo group from pre-exercise to 48 h (p=0.012) and 96 h (p=0.003) post-exercise. At 48 h post-exercise, PB-H reduced whole body and hamstring soreness (p=0.029) versus placebo. Chronic consumption of PB improved serum FRAP (p=0.039). As expected, serum cortisol and CK increased from pre- to post-exercise in all groups; however, by 96 h, cortisol and CK levels returned to pre-exercise levels following PB supplementation. At 96 h, the change in cortisol from pre- to post-exercise was significantly greater in placebo versus PB-H (p=0.039). Conclusion These findings show that chronic consumption of PB improved antioxidant status, reduced markers of muscle stress, and promoted strength recovery post-exercise. PMID:26689317

  2. Maximal force, voluntary activation and muscle soreness after eccentric damage to human elbow flexor muscles

    PubMed Central

    Prasartwuth, O; Taylor, JL; Gandevia, SC

    2005-01-01

    Muscle damage reduces voluntary force after eccentric exercise but impaired neural drive to the muscle may also contribute. To determine whether the delayed-onset muscle soreness, which develops ∼1 day after exercise, reduces voluntary activation and to identify the possible site for any reduction, voluntary activation of elbow flexor muscles was examined with both motor cortex and motor nerve stimulation. We measured maximal voluntary isometric torque (MVC), twitch torque, muscle soreness and voluntary activation in eight subjects before, immediately after, 2 h after, 1, 2, 4 and 8 days after eccentric exercise. Motor nerve stimulation and motor cortex stimulation were used to derive twitch torques and measures of voluntary activation. Eccentric exercise immediately reduced the MVC by 38 ± 3% (mean ±s.d., n = 8). The resting twitch produced by motor nerve stimulation fell by 82 ± 6%, and the estimated resting twitch by cortical stimulation fell by 47 ± 15%. While voluntary torque recovered after 8 days, both measures of the resting twitch remained depressed. Muscle tenderness occurred 1–2 days after exercise, and pain during contractions on days 1–4, but changes in voluntary activation did not follow this time course. Voluntary activation assessed with nerve stimulation fell 19 ± 6% immediately after exercise but was not different from control values after 2 days. Voluntary activation assessed by motor cortex stimulation was unchanged by eccentric exercise. During MVCs, absolute increments in torque evoked by nerve and cortical stimulation behaved differently. Those to cortical stimulation decreased whereas those to nerve stimulation tended to increase. These findings suggest that reduced voluntary activation contributes to the early force loss after eccentric exercise, but that it is not due to muscle soreness. The impairment of voluntary activation to nerve stimulation but not motor cortical stimulation suggests that the activation deficit lies in the

  3. The Effect of Eccentric Exercise-Induced Delayed-Onset Muscle Soreness on Positioning Sense and Shooting Percentage in Wheelchair Basketball Players

    PubMed Central

    Serinken, Mehmet Akif; Gençoğlu, Celal; Kayatekin, Berkant Muammer

    2013-01-01

    Background: Eccentric exercise is defined as a type of exercise in which the muscle produces power by extending. In contrast to isometric and concentric exercises, eccentric muscle activity is much more effective mechanically; however, it may expose the muscle to soreness. Delayed-Onset Muscle Soreness (DOMS) emerges a couple of hours after an eccentric activity, especially in individuals who are not used to this kind of exercise, and causes a temporary decrease in muscle performance, joint movement angle and muscle power, and also a temporary increase in the blood creatine kinase (CK) activity. Aims: This study investigates the effect of DOMS on the upper extremities motor performance by conducting an eccentric exercise load on the elbow flexor muscles. Study design: Cross sectional study. Methods: The study included 10 wheelchair basketball players. First, the participants underwent blood CK activity, positioning sense, muscle pain, shooting performance measurements tests at the base, and after 30 minutes and 24 and 48 hours. Then, one week later, the one-repetition-maximums of biceps curls were determined in order to define the intensity of the eccentric exercise. An eccentric exercise protocol which would cause DOMS was applied to all players. All tests were replaced with acute exhaustive eccentric exercise; the same tests were repeated in the same order after the exercise. Blood CK activity was measured by taking an earlobe capillary blood sample. The muscle pain level was measured by using a Visual Analogue Scale (VAS). Positioning sense loss was assessed via goniometer at 30º, 60° and 90° degrees horizontally. Results: The study found a statistically significant increase in blood CK activity and positioning sense loss, and a decrease in the pressure-pain threshold, as well as the shooting percentages in the exercise group when compared with the control. Conclusion: These findings suggest that DOMS negatively affects the upper extremities motor performance

  4. Generation of field-aligned current (FAC) and convection through the formation of pressure regimes: Correction for the concept of Dungey's convection

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Watanabe, M.; Den, M.; Fujita, S.; Ebihara, Y.; Kikuchi, T.; Hashimoto, K. K.; Kataoka, R.

    2016-09-01

    In this paper, we try to elucidate the generation mechanism of the field-aligned current (FAC) and coexisting convection. From the comparison between the theoretical prediction and the state of numerical solution from the high-resolution global simulation, we obtain the following conclusions about the distribution of dynamo, the magnetic field structure along the flow path that diverges Poynting flux, and energy conversion promoting the generation of electromagnetic energy. The dynamo for the region 1 FAC, which is in the high-latitude-side cusp-mantle region, has a structure in which magnetic field is compressed along the convection path by the slow mode motion. The dynamo for the region 2 FAC is in the ring current region at the inner edge of the plasma sheet, and has a structure in which magnetic field is curved outward along the convection path. Under these structures, electromagnetic energy is generated from the work done by pressure gradient force, in both dynamos for the region 1 and region 2 FACs. In these generation processes of the FACs, the excitation of convection and the formation of pressure regimes occur as interdependent processes. This structure leads to a modification in the way of understanding the Dungey's convection. Generation of the FAC through the formation of pressure regimes is essential even for the case of substorm onset.

  5. Nonrheumatic myopericarditis post acute streptococcal pharyngitis: An uncommon cause of sore throat with ST segment elevation.

    PubMed

    Pourmand, Ali; Gelman, Daniel; Davis, Steven; Shokoohi, Hamid

    2016-12-08

    Nonrheumatic myopericarditis is an uncommon complication of acute pharyngitis caused by Group A Streptococcal infection (GAS). While the natural history of carditis complicating acute rheumatic fever is well established, the incidence, pathophysiology and clinical course of nonrheumatic myopericarditis are ill defined. Advances in rapid bedside testing for both myocardial injury and GAS pharyngitis have allowed for increasing recognition of this uncommon complication in patients presenting with a sore throat with associated chest discomfort. We describe a case of a 34years old man with GAS pharyngitis complicated by acute myopericarditis who presented with chest pain, ST segment elevation on electrocardiogram, and elevated cardiac biomarkers.

  6. The Use of Thermal Infra-Red Imaging to Detect Delayed Onset Muscle Soreness

    PubMed Central

    Al-Nakhli, Hani H.; Petrofsky, Jerrold S.; Laymon, Michael S.; Berk, Lee S.

    2012-01-01

    Delayed onset muscle soreness (DOMS), also known as exercise induced muscle damage (EIMD), is commonly experienced in individuals who have been physically inactive for prolonged periods of time, and begin with an unexpected bout of exercise1-4, but can also occur in athletes who exercise beyond their normal limits of training5. The symptoms associated with this painful phenomenon can range from slight muscle tenderness, to severe debilitating pain1,3,5. The intensity of these symptoms and the related discomfort increases within the first 24 hours following the termination of the exercise, and peaks between 24 to 72 hours post exercise1,3. For this reason, DOMS is one of the most common recurrent forms of sports injury that can affect an individual’s performance, and become intimidating for many1,4. For the last 3 decades, the DOMS phenomenon has gained a considerable amount of interest amongst researchers and specialists in exercise physiology, sports, and rehabilitation fields6. There has been a variety of published studies investigating this painful occurrence in regards to its underlying mechanisms, treatment interventions, and preventive strategies1-5,7-12. However, it is evident from the literature that DOMS is not an easy pathology to quantify, as there is a wide amount of variability between the measurement tools and methods used to quantify this condition6. It is obvious that no agreement has been made on one best evaluation measure for DOMS, which makes it difficult to verify whether a specific intervention really helps in decreasing the symptoms associated with this type of soreness or not. Thus, DOMS can be seen as somewhat ambiguous, because many studies depend on measuring soreness using a visual analog scale (VAS)10,13-15, which is a subjective rather than an objective measure. Even though needle biopsies of the muscle, and blood levels of myofibre proteins might be considered a gold standard to some6, large variations in some of these blood

  7. Anionic chemistry of noble gases: formation of Mg-NG (NG = Xe, Kr, Ar) compounds under pressure.

    PubMed

    Miao, Mao-Sheng; Wang, Xiao-Li; Brgoch, Jakoah; Spera, Frank; Jackson, Matthew G; Kresse, Georg; Lin, Hai-Qing

    2015-11-11

    While often considered to be chemically inert, the reactivity of noble gas elements at elevated pressures is an important aspect of fundamental chemistry. The discovery of Xe oxidation transformed the doctrinal boundary of chemistry by showing that a complete electron shell is not inert to reaction. However, the reductive propensity, i.e., gaining electrons and forming anions, has not been proposed or examined for noble gas elements. In this work, we demonstrate, using first-principles electronic structure calculations coupled to an efficient structure prediction method, that Xe, Kr, and Ar can form thermodynamically stable compounds with Mg at high pressure (≥125, ≥250, and ≥250 GPa, respectively). The resulting compounds are metallic and the noble gas atoms are negatively charged, suggesting that chemical species with a completely filled shell can gain electrons, filling their outermost shell(s). Moreover, this work indicates that Mg2NG (NG = Xe, Kr, Ar) are high-pressure electrides with some of the electrons localized at interstitial sites enclosed by the surrounding atoms. Previous predictions showed that such electrides only form in Mg and its compounds at very high pressures (>500 GPa). These calculations also demonstrate strong chemical interactions between the Xe 5d orbitals and the quantized interstitial quasiatom (ISQ) orbitals, including the strong chemical bonding and electron transfer, revealing the chemical nature of the ISQ.

  8. Effects of the nozzle design on the properties of plasma jet and formation of YSZ coatings under low pressure conditions

    NASA Astrophysics Data System (ADS)

    Sun, Chengqi; Gao, Yang; Yang, Deming; Fu, Yingqing

    2016-09-01

    How to control the quality of the coatings has become a major problem during the plasma spraying. Because nozzle contour has a great influence on the characteristic of the plasma jet, two kinds of plasma torches equipped with a standard cylindrical nozzle and a converging-diverging nozzle are designed for low pressure plasma spraying(LPPS) and very low pressure plasma spraying(VLPPS). Yttria stabilized zirconia(YSZ) coatings are obtained in the reducing pressure environment. The properties of the plasma jet without or with powder injection are analyzed by optical emission spectroscopy, and the electron temperature is calculated based on the ratio of the relative intensity of two Ar I spectral lines. The results show that some of the YSZ powder can be vaporized in the low pressure enlarged plasma jet, and the long anode nozzle may improve the characteristics of the plasma jet. The coatings deposited by LPPS are mainly composed of the equiaxed grains and while the unmelted powder particles and large scalar pores appear in the coatings made by VLPPS. The long anode nozzle could improve the melting of the powders and deposition efficiency, and enhance the coatings' hardness. At the same time, the long anode nozzle could lead to a decrease in the overspray phenomenon. Through the comparison of the two different size's nozzle, the long anode is much more suitable for making the YSZ coatings.

  9. Pressure increases, the formation of chromite seams, and the development of the ultramafic series in the Stillwater Complex, Montana

    USGS Publications Warehouse

    Lipin, B.R.

    1993-01-01

    This paper explores the hypothesis that chromate seams in the Stillwater Complex formed in response to periodic increases in total pressure in the chamber. Total pressure increased because of the positive ??V of nucleation of CO2 bubbles in the melt and their subsequent rise through the magma chamber, during which the bubbles increased in volume by a factor of 4-6. By analogy with the pressure changes in the summit chambers of Kilauea and Krafla volcanoes, the maximum variation was 0.2-0.25 kbar, or 5-10% of the total pressure in the Stillwater chamber. An evaluation of the likelihood of fountaining and mixing of a new, primitive liquid that entered the chamber with the somewhat more evolved liquid already in the chamber is based upon calculations using observed and inferred velocities and flow rates of basaltic magmas moving through volcanic fissures. The calculations indicate that hot, dense magma would have oozed, rather than fountained into the chamber, and early mixing of the new and residual magmas that could have resulted in chromite crystallizing alone did not take place. -from Author

  10. On the Experimental and Theoretical Investigations of Lean Partially Premixed Combustion, Burning Speed, Flame Instability and Plasma Formation of Alternative Fuels at High Temperatures and Pressures

    NASA Astrophysics Data System (ADS)

    Askari, Omid

    This dissertation investigates the combustion and injection fundamental characteristics of different alternative fuels both experimentally and theoretically. The subjects such as lean partially premixed combustion of methane/hydrogen/air/diluent, methane high pressure direct-injection, thermal plasma formation, thermodynamic properties of hydrocarbon/air mixtures at high temperatures, laminar flames and flame morphology of synthetic gas (syngas) and Gas-to-Liquid (GTL) fuels were extensively studied in this work. These subjects will be summarized in three following paragraphs. The fundamentals of spray and partially premixed combustion characteristics of directly injected methane in a constant volume combustion chamber have been experimentally studied. The injected fuel jet generates turbulence in the vessel and forms a turbulent heterogeneous fuel-air mixture in the vessel, similar to that in a Compressed Natural Gas (CNG) Direct-Injection (DI) engines. The effect of different characteristics parameters such as spark delay time, stratification ratio, turbulence intensity, fuel injection pressure, chamber pressure, chamber temperature, Exhaust Gas recirculation (EGR) addition, hydrogen addition and equivalence ratio on flame propagation and emission concentrations were analyzed. As a part of this work and for the purpose of control and calibration of high pressure injector, spray development and characteristics including spray tip penetration, spray cone angle and overall equivalence ratio were evaluated under a wide range of fuel injection pressures of 30 to 90 atm and different chamber pressures of 1 to 5 atm. Thermodynamic properties of hydrocarbon/air plasma mixtures at ultra-high temperatures must be precisely calculated due to important influence on the flame kernel formation and propagation in combusting flows and spark discharge applications. A new algorithm based on the statistical thermodynamics was developed to calculate the ultra-high temperature plasma

  11. Effect of Low-Pressurized Perfusion with Different Concentration of Elastase on the Aneurysm Formation Rate in the Abdominal Aortic Aneurysm Model in Rabbits.

    PubMed

    Nie, Maoxiao; Yan, Yunfeng; Li, Xinhe; Feng, Tingting; Zhao, Xin; Zhang, Mingduo; Zhao, Quanming

    2016-01-01

    Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 μL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5-146.8%, and 241.5-255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate.

  12. Effect of Low-Pressurized Perfusion with Different Concentration of Elastase on the Aneurysm Formation Rate in the Abdominal Aortic Aneurysm Model in Rabbits

    PubMed Central

    Nie, Maoxiao; Yan, Yunfeng

    2016-01-01

    Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 μL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5–146.8%, and 241.5–255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate. PMID:27965979

  13. The inviscid pressure field on the tip of a semi-infinite wing and its application to the formation of a tip vortex

    NASA Technical Reports Server (NTRS)

    Hall, G. F.; Shamroth, S. J.; Mcdonald, H.; Briley, W. R.

    1976-01-01

    A method was developed for determining the aerodynamic loads on the tip of an infinitely thin, swept, cambered semi-infinite wing at an angle of attack which is operating subsonically in an inviscid medium and is subjected to a sinusoidal gust. Under the assumption of linearized aerodynamics, the loads on the tip are obtained by superposition of the steady aerodynamic results for angle of attack and camber, and the unsteady results for the response to the sinusoidal gust. The near field disturbance pressures in the fluid surrounding the tip are obtained by assuming a dipole representation for the loading on the tip and calculating the pressures accordingly. The near field pressures are used to drive a reduced form of the Navier-Stokes equations which yield the tip vortex formation. The combined viscid-inviscid analysis is applied to determining the pressures and examining the vortex rollup in the vicinity of an unswept, uncambered wing moving steadily at a Mach number of 0.2 at an angle of attack of 0.1 rad. The viscous tip flow calculation shows features expected in the tip flow such as the qualitatively proper development of boundary layers on both the upper and lower airfoil surfaces. In addition, application of the viscous solution leads to the generation of a circular type flow pattern above the airfoil suction surface.

  14. 08FFL-0020Influence of High Fuel Rail Pressure and Urea Selective Catalytic Reduction on PM Formation in an Off-Highway Heavy-Duty Diesel Engine

    SciTech Connect

    Kass, Michael D; Domingo, Norberto; Storey, John Morse; Lewis Sr, Samuel Arthur

    2008-01-01

    The influence of fuel rail pressure (FRP) and urea-selective catalytic reduction (SCR) on particulate matter (PM) formation is investigated in this paper along with notes regarding the NOx and other emissions. Increasing FRP was shown to reduce the overall soot and total PM mass for four operating conditions. These conditions included two high speed conditions (2400 rpm at 540 and 270 Nm of torque) and two moderated speed conditions (1400 rpm at 488 and 325 Nm). The concentrations of CO2 and NOx increased with fuel rail pressure and this is attributed to improved fuel-air mixing. Interestingly, the level of unburned hydrocarbons remained constant (or increased slightly) with increased FRP. PM concentration was measured using an AVL smoke meter and scanning mobility particle sizer (SMPS); and total PM was collected using standard gravimetric techniques. These results showed that the smoke number and particulate concentrations decrease with increasing FRP. However the decrease becomes more gradual as very high rail pressures. Additionally, the total PM decreased with increasing FRP; however, the soluble organic fraction (SOF) reaches a maximum after which it declines with higher rail pressure. The total PM was collected for the two 1400 rpm conditions downstream of the engine, diesel oxidation catalyst, and a urea-SCR catalyst. The results show that significant PM reduction occurs in the SCR catalyst even during high rates of urea dosage. Analysis of the PM indicates that residual SOF is burned up in the SCR catalyst.

  15. The Effect of Green Tea Gargle Solution on Sore Throat After Coronary Artery Bypass Grafting: A Randomized Clinical Trial

    PubMed Central

    Jafari, Hedayat; Ariaeifar, Mohammad Reza; Yazdani Charati, Jamshid; Soleimani, Aria; Nasiri Formi, Ebrahim

    2016-01-01

    Background Tracheal intubation is an essential method of keeping the airway open in patients under general anesthesia. Sore throat is a prevalent complication after endotracheal intubation. Objectives The aim of this study was to investigate the effect of green tea gargling on sore throat after coronary artery bypass grafting (CABG). Patients and Methods This was a single-blind, randomized clinical trial, in which 121 patients who had undergone CABG were divided into two groups: those who gargled distilled water and those who gargled a green tea solution. An hour after extubation, the patients of the intervention group were asked to gargle 30 cc of green tea, and the patients of the control group were asked to gargle 30 cc of distilled water, every 6 hours for up to 24 hours (four times per patient). A sore throat questionnaire was filled out 6, 12, and 24 hours after endotracheal extubation. Results The results showed that there were no significant differences between the two groups with regard to patient age, sex, body mass index, smoking background, and duration of anesthesia. There was no significant difference between the two groups in terms of sore throat before the intervention (P = 0.461) and 6 hours after the intervention (P = 0.901). However, a significant difference was observed between the two groups in terms of sore throat 12 hours (P = 0.047) and 24 hours (P < 0.001) after removing the endotracheal tube. Conclusions Gargling a green tea solution, an anti-inflammatory, natural, and harmless substance, can reduce the pain of sore throat in patients after endotracheal extubation. PMID:27642569

  16. Influence of Ginger and Cinnamon Intake on Inflammation and Muscle Soreness Endued by Exercise in Iranian Female Athletes

    PubMed Central

    Mashhadi, Nafiseh Shokri; Ghiasvand, Reza; Askari, Gholamreza; Feizi, Awat; Hariri, Mitra; Darvishi, Leila; Barani, Azam; Taghiyar, Maryam; Shiranian, Afshin; Hajishafiee, Maryam

    2013-01-01

    Background: Ginger rhizomes (rich in gingerols, shogaols, paradols and zingerone) have been used in Asia for the treatment of asthma, diabetes, and pain, and have shown potent anti-inflammatory attributes. Common spices such as Cinnamon (including cinnamic aldehyde and cinnamyl aldehydeis) are used in food and many studies have focused on its anti-inflammatory components. Intense exercise can result in an inflammatory response to cell damage and also muscle soreness. The efficacy of dietary ginger and cinnamon as anti-inflammatory agents and their effectiveness in reducing muscle soreness has been investigated in limited studies on humans. Therefore, we have studied the effects of dietary ginger and cinnamon on inflammation and muscle soreness in Iranian female taekwondo players. Methods: Sixty healthy, trained women, aged 13-25 years, were enrolled in the six-week investigation and randomly categorized into three groups (cinnamon, ginger or placebo) and received 3 g of ginger, cinnamon or placebo powder each day, depending on the group they belonged to. The IL-6 level and Likert Scale of Muscle Soreness were evaluated at the beginning and the end of the study and compared among the groups. Results: Forty-nine of the participants completed the six-week intervention. There were no significant changes in the IL-6 cinnamon and ginger group when compared with the placebo group, whereas, there was a significant fall in muscle soreness in the cinnamon group and placebo (P < 0.1) and ginger group and placebo (P < 0.01). Conclusions: Administration of ginger and cinnamon in athlete women for six weeks did not show any significant change in the IL-6 level, but showed a decrease in muscle soreness in the cinnamon and ginger groups. PMID:23717759

  17. In Situ Visualization of the Dynamics in Xylem Embolism Formation and Removal in the Absence of Root Pressure: A Study on Excised Grapevine Stems1[OPEN

    PubMed Central

    Knipfer, Thorsten; Cuneo, Italo F.; Brodersen, Craig R.; McElrone, Andrew J.

    2016-01-01

    Gas embolisms formed during drought can disrupt long-distance water transport through plant xylem vessels, but some species have the ability to remove these blockages. Despite evidence suggesting that embolism removal is linked to the presence of vessel-associated parenchyma, the underlying mechanism remains controversial and is thought to involve positive pressure generated by roots. Here, we used in situ x-ray microtomography on excised grapevine stems to determine if embolism removal is possible without root pressure, and if the embolism formation/removal affects vessel functional status after sample excision. Our data show that embolism removal in excised stems was driven by water droplet growth and was qualitatively identical to refilling in intact plants. When stem segments were rehydrated with H2O after excision, vessel refilling occurred rapidly (<1 h). The refilling process was substantially slower when polyethylene glycol was added to the H2O source, thereby providing new support for an osmotically driven refilling mechanism. In contrast, segments not supplied with H2O showed no refilling and increased embolism formation. Dynamic changes in liquid/wall contact angles indicated that the processes of embolism removal (i.e. vessel refilling) by water influx and embolism formation by water efflux were directly linked to the activity of vessel-associated living tissue. Overall, our results emphasize that root pressure is not required as a driving force for vessel refilling, and care should be taken when performing hydraulics measurements on excised plant organs containing living vessel-associated tissue, because the vessel behavior may not be static. PMID:27208267

  18. Studies of the mechanism of the cluster formation in a thermally sampling atmospheric pressure ionization mass spectrometer

    SciTech Connect

    Albrecht, Sascha Stroh, Fred; Klopotowski, Sebastian Derpmann, Valerie Klee, Sonja Brockmann, Klaus J. Benter, Thorsten

    2014-01-15

    In this study a thermally sampling atmospheric pressure ionization mass spectrometer is described and characterized. The ion transfer stage offers the capability to sample cluster ions at thermal equilibrium and during this transfer fundamental processes possibly affecting the cluster distribution are also readily identified. Additionally, the transfer stage combines optional collision-induced dissociation (CID) analysis of the cluster composition with thermal equilibrium sampling of clusters. The performance of the setup is demonstrated with regard to the proton-bound water cluster system. The benefit of the studied processes is that they can help to improve future transfer stages and to understand cluster ion reactions in ion mobility tubes and high-pressure ion sources. In addition, the instrument allows for the identification of fragmentation and protonation reactions caused by CID.

  19. Pressure dependent low temperature kinetics for CN + CH3CN: competition between chemical reaction and van der Waals complex formation.

    PubMed

    Sleiman, Chantal; González, Sergio; Klippenstein, Stephen J; Talbi, Dahbia; El Dib, Gisèle; Canosa, André

    2016-06-01

    The gas phase reaction between the CN radical and acetonitrile CH3CN was investigated experimentally, at low temperatures, with the CRESU apparatus and a slow flow reactor to explore the temperature dependence of its rate coefficient from 354 K down to 23 K. Whereas a standard Arrhenius behavior was found at T > 200 K, indicating the presence of an activation barrier, a dramatic increase in the rate coefficient by a factor of 130 was observed when the temperature was decreased from 168 to 123 K. The reaction was found to be pressure independent at 297 K unlike the experiments carried out at 52 and 132 K. The work was complemented by ab initio transition state theory based master equation calculations using reaction pathways investigated with highly accurate thermochemical protocols. The role of collisional stabilization of a CNCH3CN van der Waals complex and of tunneling induced H atom abstractions were also considered. The experimental pressure dependence at 52 and 132 K is well reproduced by the theoretical calculations provided that an anharmonic state density is considered for the van der Waals complex CH3CNCN and its Lennard-Jones radius is adjusted. Furthermore, these calculations indicate that the experimental observations correspond to the fall-off regime and that tunneling remains small in the low-pressure regime. Hence, the studied reaction is essentially an association process at very low temperature. Implications for the chemistry of interstellar clouds and Titan are discussed.

  20. Formation of the -N(NO)N(NO)- polymer at high pressure and stabilization at ambient conditions.

    PubMed

    Xiao, Hai; An, Qi; Goddard, William A; Liu, Wei-Guang; Zybin, Sergey V

    2013-04-02

    A number of exotic structures have been formed through high-pressure chemistry, but applications have been hindered by difficulties in recovering the high-pressure phase to ambient conditions (i.e., one atmosphere and 300 K). Here we use dispersion-corrected density functional theory [PBE-ulg (Perdew-Burke-Ernzerhof flavor of DFT with the universal low gradient correction for long range London dispersion)] to predict that above 60 gigapascal (GPa) the most stable form of N2O (the laughing gas in its molecular form) is a one-dimensional polymer with an all-nitrogen backbone analogous to cis-polyacetylene in which alternate N are bonded (ionic covalent) to O. The analogous trans-polymer is only 0.03∼0.10 eV/molecular unit less stable. Upon relaxation to ambient conditions, both polymers relax below 14 GPa to the same stable nonplanar trans-polymer. The predicted phonon spectrum and dissociation kinetics validates the stability of this trans-poly-NNO at ambient conditions, which has potential applications as a type of conducting nonlinear optical polymer with all-nitrogen chains and as a high-energy oxidizer for rocket propulsion. This work illustrates in silico materials discovery particularly in the realm of extreme conditions (very high pressure or temperature).

  1. Formation of the –N(NO)N(NO)– polymer at high pressure and stabilization at ambient conditions

    PubMed Central

    Xiao, Hai; An, Qi; Goddard, William A.; Liu, Wei-Guang; Zybin, Sergey V.

    2013-01-01

    A number of exotic structures have been formed through high-pressure chemistry, but applications have been hindered by difficulties in recovering the high-pressure phase to ambient conditions (i.e., one atmosphere and 300 K). Here we use dispersion-corrected density functional theory [PBE-ulg (Perdew-Burke-Ernzerhof flavor of DFT with the universal low gradient correction for long range London dispersion)] to predict that above 60 gigapascal (GPa) the most stable form of N2O (the laughing gas in its molecular form) is a one-dimensional polymer with an all-nitrogen backbone analogous to cis-polyacetylene in which alternate N are bonded (ionic covalent) to O. The analogous trans-polymer is only 0.03∼0.10 eV/molecular unit less stable. Upon relaxation to ambient conditions, both polymers relax below 14 GPa to the same stable nonplanar trans-polymer. The predicted phonon spectrum and dissociation kinetics validates the stability of this trans-poly-NNO at ambient conditions, which has potential applications as a type of conducting nonlinear optical polymer with all-nitrogen chains and as a high-energy oxidizer for rocket propulsion. This work illustrates in silico materials discovery particularly in the realm of extreme conditions (very high pressure or temperature). PMID:23503849

  2. Mechanisms of exercise-induced delayed onset muscular soreness: a brief review.

    PubMed

    Armstrong, R B

    1984-12-01

    Delayed-onset muscular soreness (DOMS), the sensation of pain and stiffness in the muscles that occurs from 1 to 5 d following unaccustomed exercise, can adversely affect muscular performance, both from voluntary reduction of effort and from inherent loss of capacity of the muscles to produce force. This reduction in performance is temporary; permanent impairment does not occur. A number of clinical correlates are associated with DOMS, including elevations in plasma enzymes, myoglobinemia, and abnormal muscle histology and ultrastructure; exertional rhabdomyolysis appears to be the extreme form of DOMS. Presently, the best treatment for DOMS appears to be muscular activity, although the sensation again returns following the exercise. Training for the specific contractile activity that causes DOMS reduces the soreness response. The etiology and cellular mechanisms of DOMS are not known, but a number of hypotheses exist to explain the phenomenon. The following model may be proposed: 1) high tensions (particularly those associated with eccentric exercise) in the contractile/elastic system of the muscle result in structural damage; 2) cell membrane damage leads to disruption of Ca++ homeostasis in the injured fibers, resulting in necrosis that peaks about 2 d post-exercise; and 3) products of macrophage activity and intracellular contents accumulate in the interstitium, which in turn stimulate free nerve endings of group-IV sensory neurons in the muscles leading to the sensation of DOMS.

  3. Effects of Inter-electrode Distance on Delayed Onset Muscle Soreness in Microcurrent Therapy.

    PubMed

    Lee, Jeong-Woo; Kang, Ji-Sun; Park, Soo-Ji; Yoon, Se-Won; Jeong, Seong-Kwan; Heo, Myoung

    2013-11-01

    [Purpose] This study examined the effect of the distance between the two electrodes on delayed onset muscle soreness during microcurrent therapy. [Methods] In this study 24 healthy women who hadn't exercised regularly for six months were selected and randomly divided into two groups. Delayed onset muscle soreness (DOMS) was induced and experimental Group 1 were given microcurrent treatment with the electrodes attached at a close distance evaluated. Experimental Group 2 received the same treatment with the electrodes attached at a greater distance apart. Visual analogue scale pain and the RIII reflex were evaluated after inducing DOMS and after one day, two days, three days and four days of microcurrent treatment. [Results] The visual analogue scale and amplitude of RIII amplitude only showed significant differences with the length of time of the treatment. [Conclusion] This study found that difference of interelectrode distance has no influence on VAS pain and the RIII reflex of DOMS. Although there were no significant differences in RIII amplitude, we suspect that it may be influenced by current parameters such as frequency and intensity.

  4. Muscle soreness, swelling, stiffness and strength loss after intense eccentric exercise.

    PubMed

    Cleak, M J; Eston, R G

    1992-12-01

    High-intensity eccentric contractions induce performance decrements and delayed onset muscle soreness. The purpose of this investigation was to study the magnitude and time course of such decrements and their interrelationships in 26 young women of mean(s.d.) age 21.4(3.3) years. Subjects performed 70 maximal eccentric contractions of the elbow flexors on a pulley system, specially designed for the study. The non-exercised arm acted as the control. Measures of soreness, tenderness, swelling (SW), relaxed elbow joint angle (RANG) and isometric strength (STR) were taken before exercise, immediately after exercise (AE), analysis of variance and at 24-h intervals for 11 days. There were significant (P < 0.01, analysis of variance) changes in all factors. Peak effects were observed between 24 and 96 h AE. With the exception of STR, which remained lower (P < 0.01), all variables returned to baseline levels by day 11. A non-significant correlation between pain and STR indicated that pain was not a major factor in strength loss. Also, although no pain was evident, RANG was decreased immediately AE. There was no relationship between SW, RANG and pain. The prolonged nature of these symptoms indicates that repair to damaged soft tissue is a slow process. Strength loss is considered particularly important as it continues when protective pain and tenderness have disappeared. This has implications for the therapeutic management of patients with myopathologies and those receiving eccentric exercise for rehabilitation.

  5. Muscle soreness, swelling, stiffness and strength loss after intense eccentric exercise.

    PubMed Central

    Cleak, M J; Eston, R G

    1992-01-01

    High-intensity eccentric contractions induce performance decrements and delayed onset muscle soreness. The purpose of this investigation was to study the magnitude and time course of such decrements and their interrelationships in 26 young women of mean(s.d.) age 21.4(3.3) years. Subjects performed 70 maximal eccentric contractions of the elbow flexors on a pulley system, specially designed for the study. The non-exercised arm acted as the control. Measures of soreness, tenderness, swelling (SW), relaxed elbow joint angle (RANG) and isometric strength (STR) were taken before exercise, immediately after exercise (AE), analysis of variance and at 24-h intervals for 11 days. There were significant (P < 0.01, analysis of variance) changes in all factors. Peak effects were observed between 24 and 96 h AE. With the exception of STR, which remained lower (P < 0.01), all variables returned to baseline levels by day 11. A non-significant correlation between pain and STR indicated that pain was not a major factor in strength loss. Also, although no pain was evident, RANG was decreased immediately AE. There was no relationship between SW, RANG and pain. The prolonged nature of these symptoms indicates that repair to damaged soft tissue is a slow process. Strength loss is considered particularly important as it continues when protective pain and tenderness have disappeared. This has implications for the therapeutic management of patients with myopathologies and those receiving eccentric exercise for rehabilitation. PMID:1490222

  6. Effects of therapeutic massage on gait and pain after delayed onset muscle soreness

    PubMed Central

    Han, Jun-Ho; Kim, Min-Jeong; Yang, Hyuk-Jin; Lee, Yu-Jin; Sung, Yun-Hee

    2014-01-01

    Unfamiliar or sudden exercise can induce delayed onset muscle soreness (DOMS) within 12–24 h. So, several researchers have reported various interventions to treat DOMS. Massage is generally known to eliminate muscle fatigue. However, effect of massage after DOMS is still not clear. We investigated whether the massage is effective on pain and gait after DOMS. The participants were divided into a control group (n= 10) with DOMS and an experimental group (n= 11) with the massage treated after DOMS. We induced DOMS by taking isotonic exercise with going up and down 20 times in 5-story building. We applied the massage and assessment on gastrocnemius of dominant foot. The change of gait and pain was assessed using gaitrite and algometer. In the present results, the massage on gastrocnemius after DOMS showed significant difference in pain (P< 0.05). Also, there was a significant difference in gait (P< 0.05), especially, spatial parameters (distance, step length, stride length) and temporal parameters (ambulation, heel on off time, stride velocity). Moreover, the pain relief after massage-treated in DOMS correlated with gait. These results suggest that the massage on gastrocnemius after DOMS has influence on pain and gait performance. Therefore, massage can be applied as intervention for delayed onset muscle soreness. PMID:24877051

  7. Effects of Inter-electrode Distance on Delayed Onset Muscle Soreness in Microcurrent Therapy

    PubMed Central

    Lee, Jeong-Woo; Kang, Ji-Sun; Park, Soo-Ji; Yoon, Se-Won; Jeong,, Seong-Kwan; Heo, Myoung

    2013-01-01

    [Purpose] This study examined the effect of the distance between the two electrodes on delayed onset muscle soreness during microcurrent therapy. [Methods] In this study 24 healthy women who hadn’t exercised regularly for six months were selected and randomly divided into two groups. Delayed onset muscle soreness (DOMS) was induced and experimental Group 1 were given microcurrent treatment with the electrodes attached at a close distance evaluated. Experimental Group 2 received the same treatment with the electrodes attached at a greater distance apart. Visual analogue scale pain and the RIII reflex were evaluated after inducing DOMS and after one day, two days, three days and four days of microcurrent treatment. [Results] The visual analogue scale and amplitude of RIII amplitude only showed significant differences with the length of time of the treatment. [Conclusion] This study found that difference of interelectrode distance has no influence on VAS pain and the RIII reflex of DOMS. Although there were no significant differences in RIII amplitude, we suspect that it may be influenced by current parameters such as frequency and intensity. PMID:24396208

  8. Timing influence of carbohydrate-protein ingestion on muscle soreness and next-day running performance.

    PubMed

    Greer, Beau Kjerulf; Price, Anna; Jones, Brett

    2014-06-01

    The present study investigates timing effects of a carbohydrate-protein (CHO-PROT) beverage on indicators of muscle damage and next day running performance. Nine trained subjects completed three trials of a 30 min downhill run, followed by a 1.5 mile treadmill running time trial 24 hr later in a blinded, crossover design. Either a CHO-PROT or noncaloric placebo beverage was given 30 and 5 min prior to, at the 15 min mark during, immediately after, and 30 min after the downhill running protocol. In the first treatment (T1), a total of 360 kilocalories were given 30 and 5 min prior to downhill running, as well as at the 15 min mark, with placebos used at other time points. In the second treatment (T2), an isocaloric amount was given but only immediately after and 30 min after downhill running, with placebos used at other time points. In the placebo treatment, a placebo was given at all time points. There were no significant differences in the 1.5 mile time trial or soreness between trials (p > .05). Regardless of timing, the ingestion of a CHO-PROT beverage had no effect on next day running performance or muscular soreness versus a placebo.

  9. Efficacy of massage on muscle soreness, perceived recovery, physiological restoration and physical performance in male bodybuilders.

    PubMed

    Kargarfard, Mehdi; Lam, Eddie T C; Shariat, Ardalan; Shaw, Ina; Shaw, Brandon S; Tamrin, Shamsul B M

    2016-01-01

    It is believed that sport massage after intensive exercise might improve power and perceptual recovery in athletes. However, few studies have been done in this area. This study aimed to examine the effect of massage on the performance of bodybuilders. Thirty experienced male bodybuilders were randomly assigned to either a massage group (n = 15) or a control group (n = 15). Both groups performed five repetition sets at 75-77% of 1RM of knee extensor and flexor muscle groups. The massage group then received a 30-min massage after the exercise protocol while the control group maintained their normal passive recovery. Criteria under investigation included: plasma creatine kinase (CK) level, agility test, vertical jump test, isometric torque test, and perception of soreness. All variables were measured over 6 time periods: baseline, immediately after the DOMS inducing protocol, right after the massage, and 24, 48, and 72 h after the massage. Both groups showed significant (P < .001) decreases in jumping, agility performance, and isometric torque, but significant (P < .001) increases in CK and muscle soreness levels. The massage group in general demonstrated a better recovery rate. As such, a post-exercise massage session can improve the exercise performance and recovery rate in male bodybuilders after intensive exercise.

  10. Fish oil supplementation reduces markers of oxidative stress but not muscle soreness after eccentric exercise.

    PubMed

    Gray, Patrick; Chappell, Andrew; Jenkinson, Alison McE; Thies, Frank; Gray, Stuart R

    2014-04-01

    Due to the potential anti-inflammatory properties of fish-derived long chain n-3 fatty acids, it has been suggested that athletes should regularly consume fish oils-although evidence in support of this recommendation is not clear. While fish oils can positively modulate immune function, it remains possible that, due to their high number of double bonds, there may be concurrent increases in lipid peroxidation. The current study aims to investigate the effect of fish oil supplementation on exercise-induced markers of oxidative stress and muscle damage. Twenty males underwent a 6-week double-blind randomized placebo-controlled supplementation trial involving two groups (fish oil or placebo). After supplementation, participants undertook 200 repetitions of eccentric knee contractions. Blood samples were taken presupplementation, postsupplementation, immediately, 24, 48, and 72 hr postexercise and muscle soreness/maximal voluntary contraction (MVC) assessed. There were no differences in creatine kinase, protein carbonyls, endogenous DNA damage, muscle soreness or MVC between groups. Plasma thiobarbituric acid reactive substances (TBARS) were lower (p < .05) at 48 and 72 hr post exercise and H2O2 stimulated DNA damage was lower (p < .05) immediately postexercise in the fish oil, compared with the control group. The current study demonstrates that fish oil supplementation reduces selected markers of oxidative stress after a single bout of eccentric exercise.

  11. Effects of therapeutic massage on gait and pain after delayed onset muscle soreness.

    PubMed

    Han, Jun-Ho; Kim, Min-Jeong; Yang, Hyuk-Jin; Lee, Yu-Jin; Sung, Yun-Hee

    2014-04-01

    Unfamiliar or sudden exercise can induce delayed onset muscle soreness (DOMS) within 12-24 h. So, several researchers have reported various interventions to treat DOMS. Massage is generally known to eliminate muscle fatigue. However, effect of massage after DOMS is still not clear. We investigated whether the massage is effective on pain and gait after DOMS. The participants were divided into a control group (n= 10) with DOMS and an experimental group (n= 11) with the massage treated after DOMS. We induced DOMS by taking isotonic exercise with going up and down 20 times in 5-story building. We applied the massage and assessment on gastrocnemius of dominant foot. The change of gait and pain was assessed using gaitrite and algometer. In the present results, the massage on gastrocnemius after DOMS showed significant difference in pain (P< 0.05). Also, there was a significant difference in gait (P< 0.05), especially, spatial parameters (distance, step length, stride length) and temporal parameters (ambulation, heel on off time, stride velocity). Moreover, the pain relief after massage-treated in DOMS correlated with gait. These results suggest that the massage on gastrocnemius after DOMS has influence on pain and gait performance. Therefore, massage can be applied as intervention for delayed onset muscle soreness.

  12. The Effects of Eccentric Contraction Duration on Muscle Strength, Power Production, Vertical Jump, and Soreness.

    PubMed

    Mike, Jonathan N; Cole, Nathan; Herrera, Chris; VanDusseldorp, Trisha; Kravitz, Len; Kerksick, Chad M

    2017-03-01

    Mike, JN, Cole, N, Herrera, C, VanDusseldorp, T, Kravitz, L, and Kerksick, CM. The effects of eccentric contraction duration on muscle strength, power production, vertical jump, and soreness. J Strength Cond Res 31(3): 773-786, 2017-Previous research has investigated the effects of either eccentric-only training or comparing eccentric and concentric exercise on changes related to strength and power expression, but no research to date has investigated the impact of altering the duration of either the concentric or the eccentric component on these parameters. Therefore, the purpose of this study was to assess the duration of eccentric (i.e., 2-second, 4-second vs. 6-second) muscle contractions and their effect on muscle strength, power production, vertical jump, and soreness using a plate-loaded barbell Smith squat exercise. Thirty college-aged men (23 ± 3.5 years, 178 ± 6.8 cm, 82 ± 12 kg, and 11.6 ± 5.1% fat) with 3.0 ± 1.0 years of resistance training experience and training frequency of 4.3 ± 0.9 days per week were randomized and assigned to 1 of 3 eccentric training groups that incorporated different patterns of contraction. For every repetition, all 3 groups used 2-second concentric contractions and paused for 1 second between the concentric and eccentric phases. The control group (2S) used 2-second eccentric contractions, whereas the 4S group performed 4-second eccentric contractions and the 6S group performed 6-second eccentric contractions. All repetitions were completed using the barbell Smith squat exercise. All participants completed a 4-week training protocol that required them to complete 2 workouts per week using their prescribed contraction routine for 4 sets of 6 repetitions at an intensity of 80-85% one repetition maximum (1RM). For all performance data, significant group × time (G × T) interaction effects were found for average power production across all 3 sets of a squat jump protocol (p = 0.04) while vertical jump did not reach

  13. Volatilization of low vapor pressure--volatile organic compounds (LVP-VOCs) during three cleaning products-associated activities: Potential contributions to ozone formation.

    PubMed

    Shin, Hyeong-Moo; McKone, Thomas E; Bennett, Deborah H

    2016-06-01

    There have been many studies to reduce ozone formation mostly from volatile organic compound (VOC) sources. However, the role of low vapor pressure (LVP)-VOCs from consumer products remains mostly unexplored and unaddressed. This study explores the impact of high production volume LVP-VOCs on ozone formation from three cleaning products-associated activities (dishwashing, clothes washing, and surface cleaning). We develop a model framework to account for the portion available for ozone formation during the use phase and from the down-the-drain disposal. We apply experimental studies that measured emission rates or models that were developed for estimating emission rates of organic compounds during the use phase. Then, the fraction volatilized (fvolatilized) and the fraction disposed down the drain (fdown-the-drain) are multiplied by the portion available for ozone formation for releases to the outdoor air (fO3|volatilized) and down-the-drain (fO3|down-the-drain), respectively. Overall, for chemicals used in three specific cleaning-product uses, fvolatilized is less than 0.6% for all studied LVP-VOCs. Because greater than 99.4% of compounds are disposed of down the drain during the use phase, when combined with fO3|volatilized and fO3|down-the-drain, the portion available for ozone formation from the direct releases to outdoor air and the down-the-drain disposal is less than 0.4% and 0.2%, respectively. The results from this study indicate that the impact of the studied LVP-VOCs on ozone formation is very sensitive to what occurs during the use phase and suggest the need for future research on experimental work at the point of use.

  14. Morphology transition of raft-model membrane induced by osmotic pressure: Formation of double-layered vesicle similar to an endo- and/or exocytosis

    NASA Astrophysics Data System (ADS)

    Onai, Teruaki; Hirai, Mitsuhiro

    2010-10-01

    The effect of osmotic pressure on the structure of large uni-lamellar vesicle (LUV) of the lipid mixtures of monosialoganglioside (GM1)-cholesterol-dioleoyl-phosphatidylcholine (DOPC) was studies by using wide-angle X-ray scattering (WAXS) method. The molar ratios of the mixtures were 0.1/0.1/1, 0/0.1/1, and 0/0/1. The ternary lipid mixture is a model of lipid rafts. The value of osmotic pressure was varied from 0 to 4.16×105 N/m2 by adding the polyvinylpyrrolidone (PVP) in the range from 0 to 25 % w/v. In the case of the mixtures without GM1, the rise of the osmotic pressure just enhances the multi-lamellar stacking with deceasing the inter-lamellar spacing. On the other hand, the mixture containing GM1 shows the structural transition from a uni-lamellar vesicle to a double-layered vesicle (a liposome including a smaller one inside) by the rise of osmotic pressure. In this morphology transition the total surface area of the double-layered vesicle is mostly as same as that of the LUV at the initial state. The polar head region of GM1 is bulky and highly hydrophilic due to the oligosaccharide chain containing a sialic acid residue. Then, the present results suggest that the existence of GM1 in the outer-leaflet of the LUV is essentially important for such a double-layered vesicle formation. Alternatively, a phenomenon similar to an endo- and/or exocytosis in cells can be caused simply by a variation of osmotic pressure.

  15. Sore Throats

    MedlinePlus

    ... close quarters such as a child care center, classroom, office, prison, or military installation, you are at ... written permission. Throat Get Involved Professional Development Practice Management ENT Careers Marketplace Privacy Policy Terms of Use © ...

  16. Vaginal Sores

    MedlinePlus

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  17. Canker Sores

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  20. Canker sore

    MedlinePlus

    ... which can irritate the area more.) Apply a mixture of half hydrogen peroxide and half water directly ... times a day. Rinse your mouth with a mixture of half Milk of Magnesia and half Benadryl ...

  1. Mouth sores

    MedlinePlus

    ... up to 6 weeks. The following steps can make you feel better: Avoid hot beverages and foods, spicy and salty foods, and citrus. Gargle with salt water or cool water. Eat fruit-flavored ice pops. This is helpful if you have a ...

  2. Canker Sore

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  3. Cold Sores

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  4. Canker Sores

    MedlinePlus

    ... SLS is a foaming agent found in most toothpastes and mouthwashes. Finally, not getting the right nutrition, ... you brush your teeth . Brush and rinse with toothpastes and mouthwashes that don't contain sodium lauryl ...

  5. Sore Throat

    MedlinePlus

    ... 1998familydoctor.org editorial staffProcedures & DevicesAttention-Deficit Hyperactivity Disorder (ADHD)March 2017April 1997familydoctor.org editorial staffInfants and ToddlersCytomegalovirusMarch ...

  6. Effect of total pressure on the formation and size evolution of silicon quantum dots in silicon nitride films

    SciTech Connect

    Rezgui, B.; Sibai, A.; Nychyporuk, T.; Lemiti, M.; Bremond, G.; Maestre, D.; Palais, O.

    2010-05-03

    The size of silicon quantum dots (Si QDs) embedded in silicon nitride (SiN{sub x}) has been controlled by varying the total pressure in the plasma-enhanced chemical vapor deposition (PECVD) reactor. This is evidenced by transmission electron microscopy and results in a shift in the light emission peak of the quantum dots. We show that the luminescence in our structures is attributed to the quantum confinement effect. These findings give a strong indication that the quality (density and size distribution) of Si QDs can be improved by optimizing the deposition parameters which opens a route to the fabrication of an all-Si tandem solar cell.

  7. Discontinuous phase formation and selective attack of SiC materials exposed to low oxygen partial pressure environments

    SciTech Connect

    Butt, D.P.; Tressler, R.E.; Spear, K.E.

    1993-09-01

    Three SiC materials were exposed to gas mixtures containing N{sub 2}, H{sub 2}, and CO at 1000-1300C, 1-740 torr for a few to 1000 h. Kinetic and thermodynamic studies indicate that CO is the predominant oxidizing species. A variety of corrosion processes were observed, including surface and internal pit formation, needle growth, grain boundary attack, and attack of impurities and surrounding material. In the case of a siliconized SiC, impurities such as Ca, Al, and Fe diffused rapidly through the Si matrix forming complex calcium aluminosilicates on the surface, leaving behind internal voids. Evaluation of the mechanical properties, including fractography, revealed a variety of degradative phenomena. Efforts to identify causes of pit formation suggested that the overall process was complex. Pits formed during attack of grain boundaries and regions containing transition metal impurities. Studies of single crystals showed preferential attack near impurities and crystalline defects, indicating that damaged crystals or certain crystal orientations in the polycrystalline materials are susceptible to attack. In addition, under some conditions where pit formation was observed, the strength of certain materials increased apparently due to flaw healing. It is suggested that flaws can heal in the absence of mechanical stress due to their high surface energy. However, second phases observed within partially healed surface cracks suggest impurities also contribute to the flaw healing processes.

  8. Synthesis, Direct Formation under High Pressure, Structure, and Electronic Properties of LiNbO3-type Oxide PbZnO3.

    PubMed

    Mori, Daisuke; Tanaka, Kie; Saitoh, Hiroyuki; Kikegawa, Takumi; Inaguma, Yoshiyuki

    2015-12-07

    A novel LiNbO3-type (LN-type) lead zinc oxide, PbZnO3, was successfully synthesized under high pressure and temperature. Rietveld structure refinement using synchrotron powder X-ray diffraction (XRD) data demonstrated that LN-type PbZnO3 crystallized into a trigonal structure with a polar space group (R3c). The bond valence sum estimated from the interatomic distances indicated that the sample possesses a Pb(4+)Zn(2+)O3 valence state. Polarization could evolve as a result of the repulsion between constituent cations because PbZnO3 does not contain a stereochemical 6s(2) cation or a Jahn-Teller active d(0) cation. Distortion of ZnO6 octahedra resulting from cation shift is comparable with that of d(0) TiO6 in ZnTiO3 and MnTiO3 with LN-type oxides, which leads to stabilization of the polar structure. PbZnO3 exhibited metallic behavior and temperature-independent diamagnetic character. In situ XRD measurement revealed that the formation of LN-type PbZnO3 occurred directly without the formation of a perovskite phase, which is unusual among LN-type materials obtained by high-pressure synthesis.

  9. Dimethylamine, trimethylamine, and biogenic amine formation in high-pressure processed semidried squid (Todarodes pacificius) during refrigerated storage.

    PubMed

    Gou, Jingyu; Choi, Kun-Pyo; He, Xinlong; Ahn, Juhee

    2010-09-01

    The quality properties of semidried squid treated with high-pressure processing (HPP) were investigated during refrigerated storage. The vacuum-packed semidried squid samples were subjected to 500 MPa for 0 min (HPP-0), 5 min (HPP-5), and 10 min (HPP-10) by using a custom-made high-pressure processor and stored at a refrigerated temperature for 28 d. The populations of indigenous psychrotrophic and mesophilic bacteria were effectively reduced by approximately 1 and 2 log CFU/g at the HPP-10 treatment, respectively. Compared to the control, the bacterial counts in HPP-treated semidried squid samples were maintained at low levels throughout the storage period. The increase in the amounts of dimethylamine (DMA) and trimethylamine (TMA) was more pronounced at the unpressurized control than at the HPP treatments. The production of biogenic amines (BAs) varied with HPP treatment during refrigerated storage. Therefore, the application of HPP may provide a significant improvement in the safety and quality of semidried squid.

  10. Phase formation in the (1-y)BiFeO3-yBiScO3 system under ambient and high pressure

    NASA Astrophysics Data System (ADS)

    Salak, A. N.; Khalyavin, D. D.; Pushkarev, A. V.; Radyush, Yu. V.; Olekhnovich, N. M.; Shilin, A. D.; Rubanik, V. V.

    2017-03-01

    Formation and thermal stability of perovskite phases in the BiFe1-yScyO3 system (0≤y≤0.70) were studied. When the iron-to-scandium substitution rate does not exceed about 15 at%, the single-phase perovskite ceramics with the rhombohedral R3c symmetry (as that of the parent compound, BiFeO3) can be prepared from the stoichiometric mixture of the respective oxides at ambient pressure. Thermal treatment of the oxide mixtures with a higher content of scandium results in formation of two main phases, namely a BiFeO3-like R3c phase and a cubic (I23) sillenite-type phase based on γ-Bi2O3. Single-phase perovskite ceramics of the BiFe1-yScyO3 composition were synthesized under high pressure from the thermally treated oxide mixtures. When y is between 0 and 0.25 the high-pressure prepared phase is the rhombohedral R3c with the √2ap×√2ap×2√3ap superstructure (ap 4 Å is the pseudocubic perovskite unit-cell parameter). The orthorhombic Pnma phase (√2ap×4ap×2√2ap) was obtained in the range of 0.30≤y≤0.60, while the monoclinic C2/c phase (√6ap×√2ap×√6ap) is formed when y=0.70. The normalized unit-cell volume drops at the crossover from the rhombohedral to the orthorhombic composition range. The perovskite BiFe1-yScyO3 phases prepared under high pressure are metastable regardless of their symmetry. At ambient pressure, the phases with the compositions in the ranges of 0.20≤y≤0.25, 0.30≤y<0.50 and 0.50≤y≤0.70 start to decompose above 970, 920 and 870 K, respectively.

  11. First-principles high-pressure unreacted equation of state and heat of formation of crystal 2,6-diamino-3, 5-dinitropyrazine-1-oxide (LLM-105)

    SciTech Connect

    Manaa, M. Riad Kuo, I-Feng W.; Fried, Laurence E.

    2014-08-14

    We report dispersion-corrected density functional theoretical calculations of the unreacted equation of state (EOS) of crystal 2,6-diamino-3, 5-dinitropyrazine-1-oxide (LLM-105) under hydrostatic compression of up to 45 GPa. Convergence tests for k-points sampling in the Brillouin zone show that a 3 × 1 × 2 mesh is required to reproduce the X-ray crystal structure at ambient conditions, and we confirm our finding with a separate supercell calculation. Our high-pressure EOS yields a bulk modulus of 19.2 GPa, and indicates a tendency towards anisotropic compression along the b lattice vector due to molecular orientations within the lattice. We find that the electronic energy band gap decreases from a semiconductor type of 1.3 eV at 0 GPa to quasi-metallic type of 0.6 eV at 45 GPa. The extensive intermolecular hydrogen bonds involving the oxide (–NO) and dioxide (–NO{sub 2}) interactions with the amine (–NH{sub 2}) group showed enhanced interactions with increasing pressure that should be discernible in the mid IR spectral region. We do not find evidence for structural phase transitions or chemically induced transformations within the pressure range of our study. The gas phase heat of formation is calculated at the G4 level of theory to be 22.48 kcal/mol, while we obtain 25.92 kcal/mol using the ccCA-PS3 method. Density functional theory calculations of the crystal and the gas phases provided an estimate for the heat of sublimation of 32.4 kcal/mol. We thus determine the room-temperature solid heat of formation of LLM-105 to be −9.9 or −6.5 kcal/mol based on the G4 or ccCA-PS3 methods, respectively.

  12. First-principles high-pressure unreacted equation of state and heat of formation of crystal 2,6-diamino-3, 5-dinitropyrazine-1-oxide (LLM-105).

    PubMed

    Manaa, M Riad; Kuo, I-Feng W; Fried, Laurence E

    2014-08-14

    We report dispersion-corrected density functional theoretical calculations of the unreacted equation of state (EOS) of crystal 2,6-diamino-3, 5-dinitropyrazine-1-oxide (LLM-105) under hydrostatic compression of up to 45 GPa. Convergence tests for k-points sampling in the Brillouin zone show that a 3 × 1 × 2 mesh is required to reproduce the X-ray crystal structure at ambient conditions, and we confirm our finding with a separate supercell calculation. Our high-pressure EOS yields a bulk modulus of 19.2 GPa, and indicates a tendency towards anisotropic compression along the b lattice vector due to molecular orientations within the lattice. We find that the electronic energy band gap decreases from a semiconductor type of 1.3 eV at 0 GPa to quasi-metallic type of 0.6 eV at 45 GPa. The extensive intermolecular hydrogen bonds involving the oxide (-NO) and dioxide (-NO2) interactions with the amine (-NH2) group showed enhanced interactions with increasing pressure that should be discernible in the mid IR spectral region. We do not find evidence for structural phase transitions or chemically induced transformations within the pressure range of our study. The gas phase heat of formation is calculated at the G4 level of theory to be 22.48 kcal/mol, while we obtain 25.92 kcal/mol using the ccCA-PS3 method. Density functional theory calculations of the crystal and the gas phases provided an estimate for the heat of sublimation of 32.4 kcal/mol. We thus determine the room-temperature solid heat of formation of LLM-105 to be -9.9 or -6.5 kcal/mol based on the G4 or ccCA-PS3 methods, respectively.

  13. New Insights into the Formation of Viable but Nonculturable Escherichia coli O157:H7 Induced by High-Pressure CO2

    PubMed Central

    Zhao, Feng; Wang, Yongtao; An, Haoran; Hu, Xiaosong

    2016-01-01

    ABSTRACT The formation of viable but nonculturable (VBNC) Escherichia coli O157:H7 induced by high-pressure CO2 (HPCD) was investigated using RNA sequencing (RNA-Seq) transcriptomics and isobaric tag for relative and absolute quantitation (iTRAQ) proteomic methods. The analyses revealed that 97 genes and 56 proteins were significantly changed upon VBNC state entry. Genes and proteins related to membrane transport, central metabolisms, DNA replication, and cell division were mainly downregulated in the VBNC cells. This caused low metabolic activity concurrently with a division arrest in cells, which may be related to VBNC state formation. Cell division repression and outer membrane overexpression were confirmed to be involved in VBNC state formation by homologous expression of z2046 coding for transcriptional repressor and ompF encoding outer membrane protein F. Upon VBNC state entry, pyruvate catabolism in the cells shifted from the tricarboxylic acid (TCA) cycle toward the fermentative route; this led to a low level of ATP. Combating the low energy supply, ATP production in the VBNC cells was compensated by the degradation of l-serine and l-threonine, the increased AMP generation, and the enhanced electron transfer. Furthermore, tolerance of the cells with respect to HPCD-induced acid, oxidation, and high CO2 stresses was enhanced by promoting the production of ammonia and NADPH and by reducing CO2 production during VBNC state formation. Most genes and proteins related to pathogenicity were downregulated in the VBNC cells. This would decrease the cell pathogenicity, which was confirmed by adhesion assays. In conclusion, the decreased metabolic activity, repressed cell division, and enhanced survival ability in E. coli O157:H7 might cause HPCD-induced VBNC state formation. PMID:27578754

  14. Cochrane review: Whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults.

    PubMed

    Costello, Joseph T; Baker, Philip Ra; Minett, Geoffrey M; Bieuzen, Francois; Stewart, Ian B; Bleakley, Chris

    2016-01-14

    Delayed-onset muscle soreness, or 'DOMS', affects many people after exercise and can impair future performance. It usually peaks one to four days after exercise and several strategies are used to overcome it. The effectiveness and safety of many of these strategies applied and promoted is unknown. This article is protected by copyright. All rights reserved.

  15. Towards a fully kinetic 3D electromagnetic particle-in-cell model of streamer formation and dynamics in high-pressure electronegative gases

    NASA Astrophysics Data System (ADS)

    Rose, D. V.; Welch, D. R.; Clark, R. E.; Thoma, C.; Zimmerman, W. R.; Bruner, N.; Rambo, P. K.; Atherton, B. W.

    2011-09-01

    Streamer and leader formation in high pressure devices is dynamic process involving a broad range of physical phenomena. These include elastic and inelastic particle collisions in the gas, radiation generation, transport and absorption, and electrode interactions. Accurate modeling of these physical processes is essential for a number of applications, including high-current, laser-triggered gas switches. Towards this end, we present a new 3D implicit particle-in-cell simulation model of gas breakdown leading to streamer formation in electronegative gases. The model uses a Monte Carlo treatment for all particle interactions and includes discrete photon generation, transport, and absorption for ultra-violet and soft x-ray radiation. Central to the realization of this fully kinetic particle treatment is an algorithm that manages the total particle count by species while preserving the local momentum distribution functions and conserving charge [D. R. Welch, T. C. Genoni, R. E. Clark, and D. V. Rose, J. Comput. Phys. 227, 143 (2007)]. The simulation model is fully electromagnetic, making it capable of following, for example, the evolution of a gas switch from the point of laser-induced localized breakdown of the gas between electrodes through the successive stages of streamer propagation, initial electrode current connection, and high-current conduction channel evolution, where self-magnetic field effects are likely to be important. We describe the model details and underlying assumptions used and present sample results from 3D simulations of streamer formation and propagation in SF6.

  16. Leucine-enriched essential amino acids attenuate muscle soreness and improve muscle protein synthesis after eccentric contractions in rats.

    PubMed

    Kato, Hiroyuki; Suzuki, Hiromi; Mimura, Masako; Inoue, Yoshiko; Sugita, Mayu; Suzuki, Katsuya; Kobayashi, Hisamine

    2015-06-01

    Eccentric exercise results in prolonged muscle weakness and muscle soreness, which are typical symptoms of muscle damage. Recovery from muscle damage is related to mammalian target of rapamycin (mTOR) activity. Leucine-enriched essential amino acids (LEAAs) stimulate muscle protein synthesis via activation of the mTOR pathway. Therefore, we investigated the effect of LEAAs on muscle protein synthesis and muscle soreness after eccentric contractions (EC). Male Sprague-Dawley rats (9-11 weeks old) were administered an LEAA solution (AminoL40; containing 40 % leucine and 60 % other essential amino acids) at 1 g/kg body weight or distilled water (control) 30 min before and 10 min after EC. Tibialis anterior (TA) muscle was exposed to 500 EC by electrical stimulation under anesthesia. The fractional synthesis rate (FSR; %/h) in the TA muscle was measured by incorporating L-[ring-(2)H5] phenylalanine into skeletal muscle protein. Muscle soreness was evaluated by the paw withdrawal threshold using the Randal-Selitto test with some modifications from 1 to 3 days after EC. The FSR in the EC-control group (0.147 ± 0.016 %/h) was significantly lower than in the sedentary group (0.188 ± 0.016 %/h, p < 0.05). AminoL40 administration significantly mitigated the EC-induced impairment of the FSR (0.172 ± 0.018 %/h). EC decreased the paw withdrawal threshold at 1 and 2 days after EC, which indicated that EC induced muscle soreness. Furthermore, AminoL40 administration alleviated the decreased paw withdrawal threshold. These findings suggest that LEAA supplementation improves the rate of muscle protein synthesis and ameliorates muscle soreness after eccentric exercise.

  17. The Effect of Gender and Menstrual Phase on Serum Creatine Kinase Activity and Muscle Soreness Following Downhill Running

    PubMed Central

    Oosthuyse, Tanja; Bosch, Andrew N.

    2017-01-01

    Serum creatine kinase (CK) activity reflects muscle membrane disruption. Oestrogen has antioxidant and membrane stabilising properties, yet no study has compared the CK and muscle soreness (DOMS) response to unaccustomed exercise between genders when all menstrual phases are represented in women. Fifteen eumenorrhoeic women (early follicular, EF (n = 5); late follicular, LF (n = 5); mid-luteal, ML (n = 5) phase) and six men performed 20 min of downhill running (−10% gradient) at 9 km/h. Serum CK activity and visual analogue scale rating of perceived muscle soreness were measured before, immediately, 24-h, 48-h and 72-h after exercise. The 24-h peak CK response (relative to pre-exercise) was similar between women and men (mean change (95% confidence interval): 58.5 (25.2 to 91.7) IU/L; 68.8 (31.3 to 106.3) IU/L, respectively). However, serum CK activity was restored to pre-exercise levels quicker in women (regardless of menstrual phase) than men; after 48-h post exercise in women (16.3 (−4.4 to 37.0) IU/L; 56.3 (37.0 to 75.6) IU/L, respectively) but only after 72-h in men (14.9 (−14.8 to 44.6) IU/L). Parallel to the CK response, muscle soreness recovered by 72-h in men. Conversely, the women still reported muscle soreness at 72-h despite CK levels being restored by 48-h; delayed recovery of muscle soreness appeared mainly in EF and LF. The CK and DOMS response to downhill running is gender-specific. The CK response recovers quicker in women than men. The CK and DOMS response occur in concert in men but not in women. The DOMS response in women is prolonged and may be influenced by menstrual phase. PMID:28241459

  18. The impact of a pre-loaded multi-ingredient performance supplement on muscle soreness and performance following downhill running.

    PubMed

    Ormsbee, Michael J; Ward, Emery G; Bach, Christopher W; Arciero, Paul J; McKune, Andrew J; Panton, Lynn B

    2015-01-01

    The effects of multi-ingredient performance supplements (MIPS) on perceived soreness, strength, flexibility and vertical jump performance following eccentric exercise are unknown. The purpose of this study was to determine the impact of MIPS (NO-Shotgun®) pre-loaded 4 weeks prior to a single bout of downhill running (DHR) on muscle soreness and performance. Trained male runners (n = 20) were stratified by VO2max, strength, and lean mass into two groups; MIPS (n = 10) ingested one serving daily of NO-Shotgun® for 28 days and 30 min prior to all post-testing visits, Control (CON; n = 10) consumed an isocaloric maltodextrin placebo in an identical manner as MIPS. Perceived soreness and performance measurements (strength, flexibility, and jump height) were tested on 6 occasions; 28 days prior to DHR, immediately before DHR (PRE), immediately post (POST) DHR, 24, 48, and 72 hr post-DHR. Perceived soreness significantly increased (p < 0.05) post DHR compared to PRE at all time-points, with no difference between groups. Creatine kinase (CK) and lactate dehydrogenase (LDH) increased over time (p < 0.001) with no group x time interactions (p = 0.236 and p = 0.535, respectively). Significant time effects were measured for strength (p = 0.001), flexibility (p = 0.025) and vertical jump (p < 0.001). There were no group x time interactions for any performance measurements. Consumption of MIPS for 4 weeks prior to a single bout of DHR did not affect perceived soreness, muscle damage, strength, flexibility, or jump performance compared to an isocaloric placebo in trained male runners following a single bout of DHR.

  19. The Effect of Gender and Menstrual Phase on Serum Creatine Kinase Activity and Muscle Soreness Following Downhill Running.

    PubMed

    Oosthuyse, Tanja; Bosch, Andrew N

    2017-02-23

    Serum creatine kinase (CK) activity reflects muscle membrane disruption. Oestrogen has antioxidant and membrane stabilising properties, yet no study has compared the CK and muscle soreness (DOMS) response to unaccustomed exercise between genders when all menstrual phases are represented in women. Fifteen eumenorrhoeic women (early follicular, EF (n = 5); late follicular, LF (n = 5); mid-luteal, ML (n = 5) phase) and six men performed 20 min of downhill running (-10% gradient) at 9 km/h. Serum CK activity and visual analogue scale rating of perceived muscle soreness were measured before, immediately, 24-h, 48-h and 72-h after exercise. The 24-h peak CK response (relative to pre-exercise) was similar between women and men (mean change (95% confidence interval): 58.5 (25.2 to 91.7) IU/L; 68.8 (31.3 to 106.3) IU/L, respectively). However, serum CK activity was restored to pre-exercise levels quicker in women (regardless of menstrual phase) than men; after 48-h post exercise in women (16.3 (-4.4 to 37.0) IU/L; 56.3 (37.0 to 75.6) IU/L, respectively) but only after 72-h in men (14.9 (-14.8 to 44.6) IU/L). Parallel to the CK response, muscle soreness recovered by 72-h in men. Conversely, the women still reported muscle soreness at 72-h despite CK levels being restored by 48-h; delayed recovery of muscle soreness appeared mainly in EF and LF. The CK and DOMS response to downhill running is gender-specific. The CK response recovers quicker in women than men. The CK and DOMS response occur in concert in men but not in women. The DOMS response in women is prolonged and may be influenced by menstrual phase.

  20. Submaximal delayed-onset muscle soreness: correlations between MR imaging findings and clinical measures

    NASA Technical Reports Server (NTRS)

    Evans, G. F.; Haller, R. G.; Wyrick, P. S.; Parkey, R. W.; Fleckenstein, J. L.; Blomqvist, C. G. (Principal Investigator)

    1998-01-01

    PURPOSE: To assess correlations between muscle edema on magnetic resonance (MR) images and clinical indexes of muscle injury in delayed-onset muscle soreness (DOMS) produced by submaximal exercise protocols. MATERIALS AND METHODS: Sixteen subjects performed 36 elbow flexions ("biceps curls") at one of two submaximal workloads that emphasized eccentric contractions. Changes in MR imaging findings, plasma levels of creatine kinase, and pain scores were correlated. RESULTS: Both exercise protocols produced DOMS in all subjects. The best correlation was between change in creatine kinase level and volume of muscle edema on MR images, regardless of the workload. Correlations tended to be better with the easier exercise protocol. CONCLUSION: Whereas many previous studies of DOMS focused on intense exercise protocols to ensure positive results, the present investigation showed that submaximal workloads are adequate to produce DOMS and that correlations between conventionally measured indexes of injury may be enhanced at lighter exercise intensities.

  1. Does post-exercise massage treatment reduce delayed onset muscle soreness? A systematic review

    PubMed Central

    Ernst, E.

    1998-01-01

    BACKGROUND: Delayed onset muscle soreness (DOMS) is a frequent problem after unaccustomed exercise. No universally accepted treatment exists. Massage therapy is often recommended for this condition but uncertainty exists about its effectiveness. AIM: To determine whether post-exercise massage alleviates the symptoms of DOMS after a bout of strenuous exercise. METHOD: Various computerised literature searches were carried out and located seven controlled trials. RESULTS: Most of the trials were burdened with serious methodological flaws, and their results are far from uniform. However, most suggest that post-exercise massage may alleviate symptoms of DOMS. CONCLUSIONS: Massage therapy may be a promising treatment for DOMS. Definitive studies are warranted. 


 PMID:9773168

  2. Effects of vibratory stimulations on maximal voluntary isometric contraction from delayed onset muscle soreness.

    PubMed

    Koh, Hyung-Woo; Cho, Sung-Hyoun; Kim, Cheol-Yong; Cho, Byung-Jun; Kim, Jin-Woo; Bo, Kak Hwang

    2013-09-01

    [Purpose] The aim of this study was to investigate the effect of vibratory stimulation on maximal voluntary isometric contraction (MVIC) from delayed onset muscle soreness (DOMS). [Subjects] Sixty healthy adults participated in this study. The exclusion criteria were orthopedic or neurologic disease. [Methods] The researchers induced DOMS in the musculus extensor carpi radialis longus of each participant. Subjects in the control group received no treatment. The ultrasound group received ultrasound treatment (intensity, 1.0 W/cm(2;) frequency 1 MHz; time, 10 minutes). The vibration group received vibration stimulation (frequency, 20 MHz; time, 10 minutes). Maximal voluntary isometric contraction (MVIC) was recorded at baseline, immediately after exercise, and 24, 48, and 72 hours after exercise. [Results] MVIC measurements showed statistically significant differences in the vibration group compared with the control group. [Conclusion] Vibratory stimulation had a positive effect on recovery of muscle function from DOMS.

  3. Effects of Vibratory Stimulations on Maximal Voluntary Isometric Contraction from Delayed Onset Muscle Soreness

    PubMed Central

    Koh, Hyung-Woo; Cho, Sung-Hyoun; Kim, Cheol-Yong; Cho, Byung-Jun; Kim, Jin-Woo; Bo, Kak Hwang

    2013-01-01

    [Purpose] The aim of this study was to investigate the effect of vibratory stimulation on maximal voluntary isometric contraction (MVIC) from delayed onset muscle soreness (DOMS). [Subjects] Sixty healthy adults participated in this study. The exclusion criteria were orthopedic or neurologic disease. [Methods] The researchers induced DOMS in the musculus extensor carpi radialis longus of each participant. Subjects in the control group received no treatment. The ultrasound group received ultrasound treatment (intensity, 1.0 W/cm2; frequency 1 MHz; time, 10 minutes). The vibration group received vibration stimulation (frequency, 20 MHz; time, 10 minutes). Maximal voluntary isometric contraction (MVIC) was recorded at baseline, immediately after exercise, and 24, 48, and 72 hours after exercise. [Results] MVIC measurements showed statistically significant differences in the vibration group compared with the control group. [Conclusion] Vibratory stimulation had a positive effect on recovery of muscle function from DOMS. PMID:24259922

  4. Effects of tender point acupuncture on delayed onset muscle soreness (DOMS) – a pragmatic trial

    PubMed Central

    Itoh, Kazunori; Ochi, Hideki; Kitakoji, Hiroshi

    2008-01-01

    Background Acupuncture is used to reduce inflammation and decrease pain in delayed onset muscle soreness (DOMS). This study investigates the efficacy of acupuncture on the symptoms of DOMS. Methods Thirty subjects were assigned randomly to there groups, namely the control, non-tender point and tender point groups. Measurement of pain with full elbow flexion was used as indices of efficacy. Measurements were taken before and after exercise, immediately after treatment and seven days after treatment. Results Significant differences in visual analog scores for pain were found between the control group and tender point group immediately after treatment and three days after exercise (P < 0.05, Dunnetts multiple test). Conclusion The results show that tender point acupuncture relieves muscle pain of DOMS. PMID:19032777

  5. Formation of Metal-Adducted Analyte Ions by Flame-Induced Atmospheric Pressure Chemical Ionization Mass Spectrometry.

    PubMed

    Cheng, Sy-Chyi; Wang, Chin-Hsiung; Shiea, Jentaie

    2016-05-17

    A flame-induced atmospheric pressure chemical ionization (FAPCI) source, consisting of a miniflame, nebulizer, and heated tube, was developed to ionize analytes. The ionization was performed by reacting analytes with a charged species generated in a flame. A stainless steel needle deposited with saturated alkali chloride solution was introduced into the mini oxyacetylene flame to generate alkali ions, which were reacted with analytes (M) generated in a heated nebulizer. The alkali-adducted 18-crown-6 ether ions, including (M + Li)(+), (M + Na)(+), (M + K)(+), (M + Rb)(+), and (M + Cs)(+), were successfully detected on the FAPCI mass spectra when the corresponding alkali chloride solutions were separately introduced to the flame. When an alkali chloride mixture was introduced, all alkali-adducted analyte ions were simultaneously detected. Their intensity order was as follows: (M + Cs)(+) > (M + Rb)(+) > (M + K)(+) > (M + Na)(+) > (M + Li)(+), and this trend agreed with the lattice energies of alkali chlorides. Besides alkali ions, other transition metal ions such as Ni(+), Cu(+), and Ag(+) were generated in a flame for analyte ionization. Other than metal ions, the reactive species generated in the fossil fuel flame could also be used to ionize analytes, which formed protonated analyte ions (M + H)(+) in positive ion mode and deprotonated analyte ions (M - H)(-) in negative ion mode.

  6. The formation of supersaturated solid solutions in Fe–Cu alloys deformed by high-pressure torsion

    PubMed Central

    Bachmaier, A.; Kerber, M.; Setman, D.; Pippan, R.

    2012-01-01

    Fully dense bulk nanocomposites have been obtained by a novel two-step severe plastic deformation process in the immiscible Fe–Cu system. Elemental micrometer-sized Cu and Fe powders were first mixed in different compositions and subsequently high-pressure-torsion-consolidated and deformed in a two-step deformation process. Scanning electron microscopy, X-ray diffraction and atom probe investigations were performed to study the evolving far-from-equilibrium nanostructures which were observed at all compositions. For lower and higher Cu contents complete solid solutions of Cu in Fe and Fe in Cu, respectively, are obtained. In the near 50% regime a solid solution face-centred cubic and solid solution body-centred cubic nanograined composite has been formed. After an annealing treatment, these solid solutions decompose and form two-phase nanostructured Fe–Cu composites with a high hardness and an enhanced thermal stability. The grain size of the composites retained nanocrystalline up to high annealing temperatures. PMID:22368454

  7. Formation of carbonaceous nano-layers under high interfacial pressures during lubrication with mineral and bio-based oils

    SciTech Connect

    Baltrus, John P.

    2014-01-01

    In order to better protect steel surfaces against wear under high loads, understanding of chemical reactions between lubricants and metal at high interfacial pressures and elevated temperatures needs to be improved. Solutions at 5 to 20 wt. % of zinc di-2-ethylhexyl dithio phosphate (ZDDP) and chlorinated paraffins (CP) in inhibited paraffinic mineral oil (IPMO) and inhibited soy bean oil (ISBO) were compared on a Twist Compression Tribotester (TCT) at 200 MPa. Microscopy of wear tracks after 10 seconds tribotesting showed much smoother surface profiles than those of unworn areas. X-ray photoelectron spectroscopy (XPS) coupled with Ar-ion sputtering demonstrated that additive solutions in ISBO formed 2–3 times thicker carbon-containing nano-layers compared to IPMO. The amounts of Cl, S or P were unexpectedly low and detectable only on the top surface with less than 5 nm penetration. CP blends in IPMO formed more inorganic chlorides than those in ISBO. It can be concluded that base oils are primarily responsible for the thickness of carbonaceous nano-layers during early stages of severe boundary lubrication, while CP or ZDDP additive contributions are important, but less significant.

  8. Soreness-related changes in three-dimensional running biomechanics following eccentric knee extensor exercise.

    PubMed

    Paquette, Max R; Peel, Shelby A; Schilling, Brian K; Melcher, Dan A; Bloomer, Richard J

    2017-06-01

    Runners often experience delayed onset muscle soreness (DOMS), especially of the knee extensors, following prolonged running. Sagittal knee joint biomechanics are altered in the presence of knee extensor DOMS but it is unclear how muscle soreness affects lower limb biomechanics in other planes of motion. The purpose of this study was to assess the effects of knee extensor DOMS on three-dimensional (3D) lower limb biomechanics during running. Thirty-three healthy men (25.8 ± 6.8 years; 84.1 ± 9.2 kg; 1.77 ± 0.07 m) completed an isolated eccentric knee extensor damaging protocol to elicit DOMS. Biomechanics of over-ground running at a set speed of 3.35 m s(-1)±5% were measured before eccentric exercise (baseline) and, 24 h and 48 h following exercise in the presence of knee extensor DOMS. Knee flexion ROM was reduced at 48 h (P = 0.01; d = 0.26), and peak knee extensor moment was reduced at 24 h (P = 0.001; d = 0.49) and 48 h (P < 0.001; d = 0.68) compared to baseline. Frontal and transverse plane biomechanics were unaffected by the presence of DOMS (P > 0.05). Peak positive ankle and knee joint powers and, peak negative knee joint power were all reduced from baseline to 24 h and 48 h (P < 0.05). These findings suggest that knee extensor DOMS greatly influences sagittal knee joint angular kinetics and, reduces sagittal power production at the ankle joint. However, knee extensor DOMS does not affect frontal and transverse plane lower limb joint biomechanics during running.

  9. The efficacy of frequency specific microcurrent therapy on delayed onset muscle soreness.

    PubMed

    Curtis, Denise; Fallows, Stephen; Morris, Michael; McMakin, Carolyn

    2010-07-01

    This study compared the effects of frequency specific microcurrent (FSM) therapy versus sham therapy in delayed onset muscle soreness (DOMS) in order to determine whether specific frequencies on two channels would produce better results than single channel single frequency microcurrent therapy which has been shown to be ineffective as compared to sham treatment in DOMS. 18 male and 17 female healthy participants (mean age 32+/-4.2 years) were recruited. Following a 15-min treadmill warm-up and 5 sub-maximal eccentric muscle contractions, participants performed 5 sets of 15 maximal voluntary eccentric muscle contractions, with a 1-min rest between sets, on a seated leg curl machine. Post-exercise, participants had one of their legs assigned to a treatment (T) regime (20 min of frequency specific microcurrent stimulation), while the participant's other leg acted as control (NT). Soreness was rated for each leg at baseline and at 24, 48 and 72 h post-exercise on a visual analogue scale (VAS), which ranged from 0 (no pain) to 10 (worst pain ever). No significant difference was noted at baseline p=1.00. Post-exercise there was a significant difference at 24h (T=1.3+/-1.0, NT=5.2+/-1.3, p=0.0005), at 48 h (T=1.2+/-1.1, NT=7.0+/-1.1, p=0.0005) and at 72 h (T=0.7+/-0.6, NT=4.0+/-1.6, p=0.0005). FSM therapy provided significant protection from DOMS at all time points tested.

  10. Effects of sensory-level high-volt pulsed electrical current ondelayed-onset muscle soreness.

    PubMed

    Tourville, Timothy W; Connolly, Declan A J; Reed, Brian V

    2006-09-01

    Ten healthy males and ten healthy females aged 21.5 +/- 3.2 years (mean +/- s) participated in the study, which was designed to evaluate the effectiveness of sensory level-high volt pulsed electrical current (HVPC) on delayed-onset muscle soreness (DOMS). Arm discomfort, elbow extension range of motion and isometric elbow flexion strength were obtained as baseline measurements. Delayed-onset muscle soreness was induced in the participants' dominant or non-dominant arm using two sets of 20 maximal eccentric elbow flexion contractions. After the induction of DOMS, the participants were randomly divided into an experimental condition (HVPC) or a placebo condition. The experimental condition consisted of 20 min of HVPC immediately after the induction of DOMS, and 20 min every 24 h for three consecutive days thereafter. The participants in the placebo condition received an intervention similar in design; however, no electrical current was administered. Baseline measurements were reevaluated at 24, 48, 72 and 96 h after the induction of DOMS. Three weeks later, the participants returned and the protocol was repeated on the contralateral limb, using the opposite intervention (HVPC or placebo). Repeated-measures analysis of variance revealed a significant increase in overall arm discomfort, decrease in elbow extension and decrease in isometric strength for both conditions over time. No significant main effect of treatment, or time-by-treatment interaction, was found for the HVPC condition when compared with the placebo condition for any variable. Sensory-level HVPC, as utilized in our application, was ineffective in reducing the measured variables associated with DOMS.

  11. Acute effects of ginger extract on biochemical and functional symptoms of delayed onset muscle soreness

    PubMed Central

    Hoseinzadeh, Khadijeh; Daryanoosh, Farhad; Baghdasar, Parvin Javad; Alizadeh, Hamid

    2015-01-01

    Background: Inflammation and pain induced by delayed onset muscle soreness (DOMS) as a result of eccentric exercise (EE) or unaccustomed activity cause some difficulties in exercise for athletes. The purpose of this study was to survey the effect of ginger extract on biochemical and functional symptom of delayed onset muscle soreness. Methods: In a quasi-experimental study, 36 healthy female subjects, who were recruited by intra dormitory calls, randomly divided into 3 groups, including: ginger intake 1 hour before exercise (GIBE), ginger intake immediately after exercise (GIAE) and placebo group (PL). Subjects consumed capsules contain 60 mg of ginger extract (equivalent of 2 g dried ginger powder) or placebo before and after exercise. The exercise protocol consisted of a 20 minute step test using a 46cm step at a rate of 15 steps per minute. The blood samples were taken before, 1, 24 and 48 hour after exercise to assay creatine kinase (CK) and interleukin-6 (IL-6). Muscle pain scores, isometric strength and circumference of thigh muscle, and hip range of motion were recorded at mentioned times. The analysis of variance (ANOVA) with repeated measure was used to determine the differences between groups. Results: The results showed a significant reduction of pain in GIBE compared to GIAE after 24 and 48h of EE and GIAE compared to PL (p<0.05). IL-6 changed significantly in GIBE compared to PL (p<0.05) after 1, 24, and 48h after EE. The other factors didn’t change meaningfully. Conclusion: The finding of this study suggests that 2 grams of ginger may have anti-inflammation and analgesic effect on DOMS. PMID:26793652

  12. The Effects of High-Volt Pulsed Current Electrical Stimulation on Delayed-Onset Muscle Soreness

    PubMed Central

    Butterfield, David Lynn; Draper, David O.; Ricard, Mark D.; Myrer, J. William; Schulthies, Shane S.; Durrant, Earlene

    1997-01-01

    Objective: We investigated three 30-minute high-volt pulsed current electrical stimulation (HVPC) treatments of 125 pps to reduce pain, restore range of motion (ROM), and recover strength loss associated with delayed-onset muscle soreness (DOMS). Design and Setting: Randomized, masked comparison of three 30-minute treatment and sham HVPC regimens over a 48-hour period. Subjects: Twenty-eight college students. Measurements: Subjects performed concentric and eccentric knee extensions with the right leg to induce muscle soreness. Assessments were made before and after the exercise bout and each treatment at 24, 48, and 72 hours postexercise. Results: Three separate 2 × 3 × 2 ANOVAs were used to determine significant differences (p < .05) between days, treatments, and pre-post treatment effects and significant interaction among these variables. Scheffe post hoc tests showed no significant reduction in pain perception or improvement in loss of function at 24, 48, and 72 hours postexercise. Mean pain perception assessments (0 = no pain, 10 = severe pain) for the HVPC group were 2.9, 4.5, and 3.5 and for the sham group 3.8, 4.8, and 3.5). Mean ROM losses for the HVPC group were 9.0°, 22.3°, and 26.2°, and for the sham group were 9.5°, 23.1°, and 23.0°. Mean strength losses (1RM) for the HVPC group were 25.9, 25.7, and 20.8 lbs and for the sham group were 22.3, 22.3, and 13.8 lbs. Conclusions: HVPC as we studied it was ineffective in providing lasting pain reduction and at reducing ROM and strength losses associated with DOMS. PMID:16558426

  13. Concomitant formation of different nature clusters and hardening in reactor pressure vessel steels irradiated by heavy ions

    NASA Astrophysics Data System (ADS)

    Fujii, K.; Fukuya, K.; Hojo, T.

    2013-11-01

    Specimens of A533B steels containing 0.04, 0.09 and 0.21 wt%Cu were irradiated at 290 °C to 3 dpa with 3 MeV Fe ions and subjected to atom probe analyses, transmission electron microscopy observations and hardness measurements. The atom probe analysis results showed that two types of solute clusters were formed: Cu-enriched clusters containing Mn, Ni and Si atoms as irradiation-enhanced solute atom clusters and Mn/Ni/Si-enriched clusters as irradiation-induced solute atom clusters. Both cluster types occurred in the highest Cu-content steel and the ratio of Mn/Ni/Si-enriched clusters to Cu-enriched clusters increased with irradiation doses. It was confirmed that the cluster formation was a key factor in the microstructure evolution until the high dose irradiation was reached even in the low Cu content steels though the dislocation loops with much lower density than that of the clusters were observed as matrix damage. The difference in the hardening efficiency due to the difference in the nature of the clusters was small. The irradiation-induced clustering of undersized Si atoms suggested that a clustering driving force other than vacancy-driven diffusion, probably an interstitial mechanism, may become important at higher dose rates.

  14. Effects of alloying elements on radiation hardening based on loop formation of electron-irradiated light water reactor pressure vessel model steels

    NASA Astrophysics Data System (ADS)

    Nishi, Takakuni; Hashimoto, N.; Ohnuki, S.; Yamamoto, T.; Odette, G. R.

    2011-10-01

    Electron irradiations using a high voltage electron microscope were conducted on several reactor pressure vessel model alloys in order to investigate the effects of alloying elements on the formation and development of defect clusters. In addition, the effects of alloying elements on yield stress change after irradiation were considered, comparing the mean size and number density of dislocation loops with the irradiation-induced hardening. High Cu alloys formed Cu and Mn-Ni-Si rich clusters, and these are important in determining the yield stress increase. High Ni alloys formed a high density of small dislocation loops and probably Mn-Ni-Si rich cluster, which have the effect of increasing the yield stress. High P enhanced radiation-induced segregation on grain boundary, helping prevent dislocation movement.

  15. Assessment of pH shock as a method for controlling sulfide and methane formation in pressure main sewer systems.

    PubMed

    Gutierrez, Oriol; Sudarjanto, Gatut; Ren, Guo; Ganigué, Ramon; Jiang, Guangming; Yuan, Zhiguo

    2014-01-01

    Caustic dosing to raise pH above 10.0 for short periods (hours) is often used by water utilities for controlling sulfide formation in sewers. However the effectiveness of this strategy is rarely reported and the impact of pH level and exposure time on the effectiveness is largely unknown. The effectiveness of this strategy under various pH levels (10.5-12.5) and exposure time (0.5-6.0 h) in controlling sulfide and methane production was evaluated in laboratory scale anaerobic sewer reactors and then in a real sewer system. Laboratory studies showed that the sulfide production rate of the laboratory sewer biofilm was reduced by 70-90% upon the completion of the pH shock, while the methane production rate decreased by 95-100%. It took approximately one week for the sulfate-reducing activity to recover to normal levels. In comparison, the methanogenic activities recovered to only about 10% in 4 weeks. The slow recovery is explained by the substantially loss of cell viability upon pH shocks, which recovered slowly after the shocks. Laboratory studies further revealed that a pH level of 10.5 for 1-2 h represent cost-effective conditions for the pH shock treatment. However, field trials showed a higher pH (11.5) and larger dosing times are needed due to the pH decreases along the sewer line and at the two ends of the caustic-receiving wastewater slugs due to dilution. To have effective sulfide and methane control, it is important to ensure effective conditions (pH > 10.5 and duration >1-2 h) for the entire sewer line.

  16. The isolated and combined effects of selected physical activity and ibuprofen on delayed-onset muscle soreness.

    PubMed

    Rahnama, N; Rahmani-Nia, F; Ebrahim, K

    2005-08-01

    Delayed-onset muscle soreness refers to the skeletal muscle pain that is experienced following eccentric exercise. The aim of the present study was to examine the physiological effects of physical activity with or without ibuprofen on delayed onset muscle soreness. Forty-four non-athletic male volunteers (age 24.3 +/- 2.4 years) were randomly assigned to one of four groups: physical activity (n = 11), ibuprofen (n = 11), physical activity and ibuprofen (combination, n = 11), or control (n = 11). The physical activity programme comprised 5 min of walking and jogging, 10 min of static stretching of the hands and shoulder girdle, and 5 min of concentric movements with sub-maximal contractions. The total amount of ibuprofen consumed by a single individual was 2800 mg; this was taken from 1 h before the eccentric actions up to 48 h after it. Delayed onset muscle soreness was induced by performing 70 eccentric contractions of the biceps muscle of the non-dominant side on a modified arm curl machine. Perceived muscle soreness, maximal eccentric contraction, creatine kinase enzyme activity and elbow range of motion were assessed 1 h before and 1, 24 and 48 h after the eccentric actions. The results indicated that, after the eccentric actions, soreness increased (P < 0.001) across time in all groups, with the highest values being recorded at 24 h. At 24 and 48 h, greater soreness (P < 0.001) was observed in the control group than in the physical activity and combination groups. After the eccentric actions, creatine kinase increased and was elevated (P < 0.001) compared with baseline in all groups, with values returning to baseline in the physical activity and combination groups by 48 h. However, creatine kinase in the control and ibuprofen groups was still significantly higher than at baseline after 48 h. Creatine kinase was higher (P < 0.001) in the control group than in physical activity and combination groups at 24 and 48 h. There was also a reduction (P < 0.001) in

  17. Studies on the Tempo of Bubble Formation in Recently Cavitated Vessels: A Model to Predict the Pressure of Air Bubbles1

    PubMed Central

    Wang, Yujie; Pan, Ruihua; Tyree, Melvin T.

    2015-01-01

    A cavitation event in a vessel replaces water with a mixture of water vapor and air. A quantitative theory is presented to argue that the tempo of filling of vessels with air has two phases: a fast process that extracts air from stem tissue adjacent to the cavitated vessels (less than 10 s) and a slow phase that extracts air from the atmosphere outside the stem (more than 10 h). A model was designed to estimate how water tension (T) near recently cavitated vessels causes bubbles in embolized vessels to expand or contract as T increases or decreases, respectively. The model also predicts that the hydraulic conductivity of a stem will increase as bubbles collapse. The pressure of air bubbles trapped in vessels of a stem can be predicted from the model based on fitting curves of hydraulic conductivity versus T. The model was validated using data from six stem segments each of Acer mono and the clonal hybrid Populus 84K (Populus alba × Populus glandulosa). The model was fitted to results with root mean square error less than 3%. The model provided new insight into the study of embolism formation in stem tissue and helped quantify the bubble pressure immediately after the fast process referred to above. PMID:25907963

  18. Defect formation in aqueous environment: Theoretical assessment of boron incorporation in nickel ferrite under conditions of an operating pressurized-water nuclear reactor (PWR)

    NASA Astrophysics Data System (ADS)

    Rák, Zs.; Bucholz, E. W.; Brenner, D. W.

    2015-06-01

    A serious concern in the safety and economy of a pressurized water nuclear reactor is related to the accumulation of boron inside the metal oxide (mostly NiFe2O4 spinel) deposits on the upper regions of the fuel rods. Boron, being a potent neutron absorber, can alter the neutron flux causing anomalous shifts and fluctuations in the power output of the reactor core. This phenomenon reduces the operational flexibility of the plant and may force the down-rating of the reactor. In this work an innovative approach is used to combine first-principles calculations with thermodynamic data to evaluate the possibility of B incorporation into the crystal structure of NiFe2O4 , under conditions typical to operating nuclear pressurized water nuclear reactors. Analyses of temperature and pH dependence of the defect formation energies indicate that B can accumulate in NiFe2O4 as an interstitial impurity and may therefore be a major contributor to the anomalous axial power shift observed in nuclear reactors. This computational approach is quite general and applicable to a large variety of solids in equilibrium with aqueous solutions.

  19. Management of post-ethmoidectomy crust formation: randomized single-blind clinical trial comparing pressurized seawater versus antiseptic/mucolytic saline.

    PubMed

    Pigret, D; Jankowski, R

    1996-03-01

    This study compared the efficacy of mechanical nasal lavages with pressurized seawater versus nasal irrigations with saline plus benzododecinium (antiseptic) plus oleosorbate (mucolytic). Twenty patients agreed to participate in a randomized, single-blind clinical trial. All patients underwent endoscopic endonasal ethmoidectomy for nasal polyps. The packing was removed after 48 h and patients were asked to start the same day nasal lavages three times a day. Clinical evaluations were performed: (1) by weighing residual nasal crusts and secretions after 21 +/- 2 days; and (2) by using visual analogue scales to daily record symptom scores. Data are presented as mean +/- SEM. T-test statistics for two independent groups were applied. The mean residual crust and secretion weights were 1,756 +/- 688 mg and 1,033 +/- 422 mg in the pressurized seawater group, 932 +/- 414 mg and 1,222 +/- 435 mg in the antiseptic-mucolytic saline group. No statistical differences were found. Sample size calculations showed that 100 subjects in each group would be necessary to confirm a 700-mg reduction in residual crusts in the antiseptic/mucolytic saline group (power = 0.80; two-sided type-I error = 0.05). Daily symptom score curves were similar in both groups and allowed us to give a description of post-operative complaints. The role of antiseptic, mucolytic and mechanical lavages in preventing post-ethmoidectomy crust formation is discussed.

  20. Contribution of low vapor pressure-volatile organic compounds (LVP-VOCs) from consumer products to ozone formation in urban atmospheres

    NASA Astrophysics Data System (ADS)

    Shin, Hyeong-Moo; McKone, Thomas E.; Bennett, Deborah H.

    2015-05-01

    Because recent laboratory testing indicates that some low vapor pressure-volatile organic compounds (LVP-VOC) solvents readily evaporate at ambient conditions, LVP-VOCs used in some consumer product formulations may contribute to ozone formation. The goal of this study is to determine the fraction of LVP-VOCs available for ozone formation from the use of consumer products for two hypothetical emissions. This study calculates and compares the fraction of consumed product available for ozone formation as a result of (a) volatilization to air during use and (b) down-the-drain disposal. The study also investigates the impact of different modes of releases on the overall fraction available in ambient air for ozone formation. For the portion of the LVP-VOCs volatilized to air during use, we applied a multi-compartment mass-balance model to track the fate of emitted LVP-VOCs in a multimedia urban environment. For the portion of the LVP-VOCs disposed down the drain, we used a wastewater treatment plant (WWTP) fate model to predict the emission rates of LVP-VOCs to ambient air at WWTPs or at the discharge zone of the facilities and then used these results as emissions in the multimedia urban environment model. In a WWTP, the LVP-VOCs selected in this study are primarily either biodegraded or removed via sorption to sludge depending on the magnitude of the biodegradation half-life and the octanol-water partition coefficient. Less than 0.2% of the LVP-VOCs disposed down the drain are available for ozone formation. In contrast, when the LVP-VOC in a consumer product is volatilized from the surface to which it has been applied, greater than 90% is available for photochemical reactions either at the source location or in the downwind areas. Comparing results from these two modes of releases allows us to understand the importance of determining the fraction of LVP-VOCs volatilized versus disposed down the drain when the product is used by consumers. The results from this study

  1. Deformation microstructures and mechanisms in the high-pressure granulites of the Bacariza Formation (Cabo Ortegal, NW Spain): going up to the surface

    NASA Astrophysics Data System (ADS)

    Puelles, P.; Abalos, B.

    2009-04-01

    The Cabo Ortegal complex is a nappe stack formed by fragments of subducted continental and oceanic lithosphere emplaced onto the Gondwana edge during the Variscan orogeny. The nappe units of Cabo Ortegal were metamorphosed under different high-pressure (HP) conditions and currently are separated by ductile tectonic contacts. They include mappable ultramafic massifs, N-MORB eclogites, metagabbros, metaserpentinites, metaperidotites, ortho- and paragneisses, and the Bacariza Formation granulites. The primary structure consists of the ultramafic massifs tectonically resting on top of the granulites of the Bacariza Formation, which overlie eclogites and HP gneisses with eclogite boudins. Granulites of the Bacariza Formation are mainly basic to intermediate in composition, although granulitic, carbonate-rich or mineralogically more exotic varieties also exist. On the basis of modal variations in the abundance of mafic and felsic mineral several lithotypes have been differentiated in order of decreasing outcrop area: (G1) plagio-pyrigarnites or common mafic granulites, (G2) intermediate to felsic, plagioclase-rich granulites, (G3) Mg-rich mafic granulites, (G4) pyrigarnite, or plagioclase-poor ultramafic granulites, and (G5) granulitic orthogneisses. The Bacariza Formation recorded a high-pressure metamorphic event. This event was polyphasic and two deformational phases are differentiated, D1 and D2, namely. D2 is associated to amalgamation of eclogite, high-pressure granulitic rocks and ultramafic sheets in deep portions of a subduction channel during the initial exhumation of the complex. As a result, transposition of the previous D1 fabrics took place due to the development of spectacular shear zones at the contacts with the bounding units. Pressure and temperature conditions estimated from the D2 mineral assemblage in equilibrium yield values of ca. 1.4 GPa and 740 °C, respectively. In this work we present a detailed study of a D2 shear zone located at the contact

  2. Managing Pressures Ulcers in a Resource Constrained Situation: A Holistic Approach

    PubMed Central

    Dam, Abhijit; Datta, Nivedita; Mohanty, Usha Rani; Bandhopadhyay, Chandreyi

    2011-01-01

    Managing pressure ulcers remain a challenge and call for a multidisciplinary team approach to care. Even more daunting is the management of such patients in remote locations and in resource constrained situations. The management of pressure sores in a patient with progressive muscular atrophy has been discussed using resources that were locally available, accessible, and affordable. Community participation was encouraged. A holistic approach to care was adopted. PMID:22346055

  3. Linear and nonlinear analyses of multi-channel mechanomyographic recordings reveal heterogeneous activation of wrist extensors in presence of delayed onset muscle soreness.

    PubMed

    Madeleine, Pascal; Hansen, Ernst A; Samani, Afshin

    2014-12-01

    In this study, we applied multi-channel mechanomyographic (MMG) recordings in combination with linear and nonlinear analyses to investigate muscular and musculotendinous effects of high intensity eccentric exercise. Twelve accelerometers arranged in a 3 × 4 matrix over the dominant elbow muscles were used to detect MMG activity in 12 healthy participants. Delayed onset muscle soreness was induced by repetitive high intensity eccentric contractions of the wrist extensor muscles. Average rectified values (ARV) as well as percentage of recurrence (%REC) and percentage of determinism (%DET) extracted from recurrence quantification analysis were computed from data obtained during static-dynamic contractions performed before exercise, immediately after exercise, and in presence of muscle soreness. A linear mixed model was used for the statistical analysis. The ARV, %REC, and %DET maps revealed heterogeneous MMG activity over the wrist extensor muscles before, immediately after, and in presence of muscle soreness (P<0.01). The ARVs were higher while the %REC and %DET were lower in presence of muscle soreness compared with before exercise (P<0.05). The study provides new key information on linear and nonlinear analyses of multi-channel MMG recordings of the wrist extensor muscles following eccentric exercise that results in muscle soreness. Recurrence quantification analysis can be suggested as a tool for detection of MMG changes in presence of muscle soreness.

  4. Various Treatment Techniques on Signs and Symptoms of Delayed Onset Muscle Soreness

    PubMed Central

    Gulick, Dawn T.; Kimura, Iris F.; Sitler, Michael; Paolone, Albert; Kelly, John D.

    1996-01-01

    Eccentric activities are an important component of physical conditioning and everyday activities. Delayed onset muscle soreness (DOMS) can result from strenuous eccentric tasks and can be a limiting factor in motor performance for several days after exercise. An efficacious method of treatment for DOMS would enhance athletic performance and hasten the return to activities of daily living. The purpose of this study was to identify a treatment method which could assist in the recovery of DOMS. In the selection of treatment methods, emphasis was directed toward treatments that could be rendered independently by an individual, therefore making the treatment valuable to an athletic trainer in team setting. DOMS was induced in 70 untrained volunteers via 15 sets of 15 eccentric contractions of the forearm extensor muscles on a Lido isokinetic dynamometer. All subjects performed a pilot exercise bout for a minimum of 9 weeks before data collection to assure that DOMS would be produced. Data were collected on 15 dependent variables: active and passive wrist flexion and extension, forearm girth, limb volume, visual analogue pain scale, muscle soreness index, isometric strength, concentric and eccentric wrist total work, concentric and eccentric angle of peak torque. Data were collected on six occasions: pre- and post-induced DOMS, 20 minutes after treatment, and 24, 48, and 72 hours after treatment. Subjects were randomly assigned to 1 of 7 groups (6 treatment and 1 control). Treatments included a nonsteroidal anti-inflammatory drug, high velocity concentric muscle contractions on an upper extremity ergometer, ice massage, 10-minute static stretching, topical Amica montana ointment, and sublingual A. montana pellets. A 7 × 6 ANOVA with repeated measures on time was performed on the delta values of each of the 15 dependent variables. Significant main effects (p < .05) were found for all of the dependent variables on time only. There were no significant differences between

  5. Marine oil dietary supplementation reduces delayed onset muscle soreness after a 30 km run

    PubMed Central

    Baum, Klaus; Telford, Richard D; Cunningham, Ross B

    2013-01-01

    Objective Runners are prone to delayed onset muscle soreness (DOMS) during long distance training. This especially holds for unaccustomed training volumes at moderate to high intensities. We investigated the effects of a marine oil complex, PCSO-524®, derived from the New Zealand green-lipped mussel (formulated as Lyprinol® and Omega XL®) on DOMS after a 30 km training run. Methods Initially, peak oxygen uptake of 32 distance runners (4 female, 28 male; median age 45 years, range 28–53) was measured on a treadmill with a 1.5 km hour−1 increase every 4 minutes starting from 8.5 km hour−1. At least 1-week after this initial test, they participated in a 30 km road run at a speed corresponding to about 70% of their individual peak oxygen uptake on a flat terrain. Before and after (0, 24, and 48 hours) the run, blood concentration of creatine kinase (CK) were measured and pain sensation was determined (pain scale from 0 = no pain to 10 = extremely painful). Runners were then matched in pairs based on maximal CK and peak oxygen uptake, and allocated randomly into two different groups. One group was supplemented with 400 mg per day of PCSO-524® for 11 weeks, the other group with an olive oil placebo. After that period, CK and pain sensations were remeasured following a second 30 km run at the same speed and on the same terrain. Results The general pattern of soreness in the PCSO-524® supplemented group was reduced by 1.1 units (standard error 0.41) compared to the placebo (P < 0.05), the effects being greater in lesser trained runners (P < 0.05). CK levels were positively associated with pain sensation (P < 0.05), but trends toward lower CK in the PCSO-524® group, which were also more pronounced in the lesser trained runners, were not statistically significant. Conclusion Pain sensations experienced by distance runners following a 30 km run were reduced by supplementation with the marine oil complex PCSO-524®, an effect which was greater in lesser trained

  6. Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat

    PubMed Central

    Morokutti-Kurz, Martina; Graf, Christine; Prieschl-Grassauer, Eva

    2017-01-01

    Up to 80% of sore throats are caused by viruses. Several over the counter products are available which provide symptomatic, not causal relief. For such lozenges, containing the antiseptics and local anesthetics amylmetacresol (AMC) and 2,4-dichlorobenzyl alcohol (DCBA) or hexylresorcinol (HR), recently an additional virucidal effect was published. Therefore, we tested a set of Strepsils® lozenges, containing either HR (Max [#2]) or AMC/DCBA (Original [#3], Extra Strong [#4], Warm [#5], Orange and Vitamin C [#6], Sugar free Lemon [#7], Children/Strawberry [#8] and Soothing Honey and Lemon [#9]) for their antiviral efficiency against representatives of respiratory viruses known to cause sore throat: human rhinovirus (HRV) 1a, HRV8, influenza virus A H1N1n, Coxsackievirus A10, and human coronavirus (hCoV) OC43. The lozenges were tested head to head with Coldamaris® lozenges (#1), which contain the patented antiviral iota-carrageenan. None of the tested AMC/DCBA or HR containing lozenges shows any antiviral effectiveness against HRV8 at the tested concentrations, whereas all are moderately active against HRV1a. Only lozenge #5 shows any activity against hCoV OC43 and Coxsackievirus A10 at the tested concentrations. Similarly, only lozenge #3 is moderately active against influenza A H1N1n virus. The data indicates that neither the isolated effect of the active ingredients nor the pH but rather one or more of the excipients of the specific formulations are responsible for the antiviral effect of some of the AMC/DCBA or HR containing lozenges. In contrast, carrageenan-containing lozenges are highly active against all viruses tested. In another experiment, we showed that binding and inactivation of virus particles by iota-carrageenan are fast and highly effective. During the residence time of the lozenge in the mouth, the viral titer is reduced by 85% and 91% for influenza A virus and hCoV OC43, respectively. Carrageenan-containing lozenges are, therefore, suitable as

  7. A clinical score to reduce unnecessary antibiotic use in patients with sore throat

    PubMed Central

    McIsaac, W J; White, D; Tannenbaum, D; Low, D E

    1998-01-01

    OBJECTIVE: To validate a score based on clinical symptoms and signs for the identification of group A Streptococcus (GAS) infection in general practice patients with score throat. DESIGN: A single throat swab was used as the gold standard for diagnosing GAS infection. Clinical information was recorded by experienced family physicians on standardized encounter forms. Score criteria were identified by means of logistic regression modelling of data from patients enrolled in the first half of the study. The score was then validated among the remaining patients. SETTING: University-affiliated family medicine centre in Toronto. PATIENTS: A total of 521 patients aged 3 to 76 years presenting with a new upper respiratory tract infection from December 1995 to February 1997. OUTCOME MEASURES: Sensitivity, specificity and likelihood ratios for identification of GAS infection with the score approach compared with throat culture. Proportion of patients prescribed antibiotics, throat culture use, and sensitivity and specificity with usual physician care and with score-based recommendations were compared. RESULTS: A score was developed ranging in value from 0 to 4. The sensitivity of the score for identifying GAS infection was 83.1%, compared with 69.4% for usual physician care (p = 0.06); the specificity values of the 2 approaches were similar. Among patients aged 3 to 14 years, the sensitivity of the score approach was higher than that of usual physician care (96.9% v. 70.6%) (p < 0.05). The proportion of patients receiving initial antibiotic prescriptions would have been reduced 48% by following score-based recommendations compared with observed physician prescribing (p < 0.001), without any increase in throat culture use. CONCLUSIONS: An age-appropriate sore throat score identified GAS infection in children and adults with sore throat better than usual care by family physicians, with significant reductions in unnecessary prescribing of antibiotics. A randomized trial

  8. Efficacy and safety of ambroxol lozenges in the treatment of acute uncomplicated sore throat. EBM-based clinical documentation.

    PubMed

    de Mey, Christian; Peil, Hubertus; Kölsch, Stephan; Bubeck, Jürgen; Vix, Jean-Michel

    2008-01-01

    Sore throat is the hallmark of acute pharyngitis. Although usually caused by viral infections, it is frequently treated with antibiotics. Such inappropriate use of antibiotics might best be challenged by offering efficacious and safe symptomatic pain relief instead. However, there is need for robust evidence to support such alternatives. Presently, the evidence from randomised, placebo-controlled, double-blind clinical trials (RCT) with the local anaesthetic ambroxol (CAS 23828-92-4) in the treatment of sore throat is being reviewed. This relates to five RCT in 1,772 patients; 1,713 were evaluable with regard to efficacy. Treatment with ambroxol lozenges was statistically significantly superior to placebo in reducing sore throat pain intensity with a high level of consistency of the estimated effect across the different studies. The effect had an early onset and lasted up to at least 3 h after a single first lozenge. The pain relief was associated with a statistically superior regression of pharyngeal redness and inflammation; with ambroxol, the overall efficacy was more frequently rated as at least "good". Treatment with the ambroxol lozenges was well tolerated. There was heterogeneity in reporting adverse events: in one later study with less severe baseline pain intensity there was more frequent reporting of hypoaesthesia of the oral cavity and tongue as an untoward phenomenon. In patients with more severe baseline pain this reflection of the medication's pharmacological action was only rarely reported as untoward. It is concluded that lozenges containing 20 mg ambroxol are a safe and efficacious treatment for acute uncomplicated sore throat of recent onset in adult patients.

  9. Echinacea/sage or chlorhexidine/lidocaine for treating acute sore throats: a randomized double-blind trial

    PubMed Central

    2009-01-01

    Background The aim of this trial was to assess the relative efficacy of a sage/echinacea spray and a chlorhexidine/lidocaine spray in the treatment of acute sore throats. Methods This was a multicenter, randomized, double-blind, double-dummy controlled trial carried out in eleven general practices in Switzerland. A total of 154 patients (133 analyzed in per protocol collective) at least 12 years old with acute sore throat present for not more than 72 hours prior to inclusion and with a throat score ≥6 participated in the study. They used either an echinacea/sage spray or a chlorhexidine/lidocaine spray with two puffs every 2 hours, in a double-dummy blinded manner, up to 10 times daily until they were symptom-free, for a maximum of 5 days. The main outcome measures was the comparison of response rates during the first three days. A response was defined as a decrease of at least 50% of the total symptoms compared to baseline. Results The echinacea/sage treatment exhibited similar efficacy to the chlorhexidine/lidocaine treatment in reducing sore throat symptoms during the first 3 days (P(x < Y) = .5083). Response rates after 3 days were 63.8% in the echinacea/sage group and 57.8% in the chlorhexidine/lidocaine group. For all secondary parameters, such as time to becoming symptom free, throat pain, and global assessments of efficacy by the physician and patient, no difference between the two treatments was seen. They were both very well tolerated. Conclusion An echinacea/sage preparation is as efficacious and well tolerated as a chlorhexidine/lidocaine spray in the treatment of acute sore throats. PMID:19748859

  10. A COMPARISON OF TOPICAL MENTHOL TO ICE ON PAIN, EVOKED TETANIC AND VOLUNTARY FORCE DURING DELAYED ONSET MUSCLE SORENESS

    PubMed Central

    Johar, Pramod; Grover, Varun; Topp, Robert

    2012-01-01

    Purpose/Background: Pain can adversely affect muscle functioning by inhibiting muscle contractions. Delayed onset muscle soreness was used as a tool to ascertain whether a topical menthol-based analgesic or ice was more effective at reducing pain and permitting greater muscular voluntary and evoked force. Methods: Sixteen subjects were randomized to receive either a topical gel containing 3.5% menthol or topical application of ice to the non-dominant elbow flexors two days following the performance of an exercise designed to induce muscle soreness. Two days later, DOMS discomfort was treated with a menthol based analgesic or ice. Maximum voluntary contractions and evoked tetanic contractions of the non-dominant elbow flexors were measured at baseline prior to inducing muscle soreness (T1), two days following inducing DOMS after 20 (T2), 25 (T3) and 35 (T4) minutes of either menthol gel or ice therapy. Pain perception using a 10-point visual analog scale was also measured at these four data collection points. Treatment analysis included a 2 way repeated measures ANOVA (2 × 4). Results: Delayed onset muscle soreness decreased (p = 0.04) voluntary force 17.1% at T2 with no treatment effect. Tetanic force was 116.9% higher (p<0.05) with the topical analgesic than ice. Pain perception at T2 was significantly (p=0.02) less with the topical analgesic versus ice. Conclusions: Compared to ice, the topical menthol-based analgesic decreased perceived discomfort to a greater extent and permitted greater tetanic forces to be produced. Level of Evidence: Level 2b PMID:22666646

  11. The effect of a prophylactic dose of flurbiprofen on muscle soreness and sprinting performance in trained subjects.

    PubMed

    Semark, A; Noakes, T D; St Clair Gibson, A; Lambert, M I

    1999-03-01

    The aim of this study was to examine the effects of a prophylactic dose of a local, transcutaneously administered, non-steroidal anti-inflammatory drug on muscle soreness, muscle damage and sprinting performance in young trained males. Twenty-five subjects aged 19+/-3 years, actively participating in rugby union and field hockey, were familiarized with the test procedure and then divided at random into an experimental group (n = 13) and a control group (n = 12). The experimental group received two patches, each containing 40 mg flurbiprofen (TransAct LAT), 12 h before an exercise bout designed to produce delayed-onset soreness (DOMS). The control group received identical non-medicated placebo patches at the same time. Delayed-onset muscle soreness was induced by an exercise protocol consisting of drop jumps (seven sets of 10 repetitions). Serum creatine kinase activity, muscle soreness, muscle girth and acceleration in a maximal sprint over 30 m were measured before the induction of DOMS and at 12, 24, 48 and 72 h thereafter. Plasma lactate concentration was measured 3 min after the 30-m sprint tests. Subjects in both groups had significantly more pain at 24 and 48 h compared with at 12 and 72 h (P < 0.05; Friedman two-way analysis of variance). Thigh girth and serum creatine kinase did not change throughout the experiment. Although plasma lactate concentrations were elevated after the 30-m sprint, there were no differences between groups or as a result of DOMS. The greatest acceleration occurred between 5 and 10 m. This was not affected by the anti-inflammatory drug or DOMS. In conclusion, the aetiology of the DOMS induced in the trained subjects in this study seems to be independent of inflammatory processes or, more specifically, of increases in prostaglandin synthesis in the muscles.

  12. The effect of kinesio taping versus stretching techniques on muscle soreness, and flexibility during recovery from nordic hamstring exercise.

    PubMed

    Ozmen, Tarik; Yagmur Gunes, Gokce; Dogan, Hanife; Ucar, Ilyas; Willems, Mark

    2017-01-01

    The purpose of this study was to examine the effects of static stretching, proprioceptive neuromuscular facilitation (PNF) stretching, or kinesio taping (KT) on muscle soreness and flexibility during recovery from exercise. Sixty-five females were randomly assigned to four groups: PNF stretching (n = 15), static stretching (n = 16), KT (n = 17), and control (n = 17). All participants performed nordic hamstring exercise (5 sets of 8 repetitions). In all groups, hamstring flexibility at 24 h and 48 h was not changed from baseline (p > .05). The muscle soreness was measured higher at 48 h post-exercise compared with baseline in the control group (p = .04) and at 24 h post-exercise compared with baseline in the PNF group (p < .01). No significant differences were found for intervention groups compared with control group in all measurements (p > .05). The KT application and pre-exercise stretching have no contribute to flexibility at 24 h and 48 h after exercise, but may attenuate muscle soreness.

  13. Resveratrol exerts no effect on inflammatory response and delayed onset muscle soreness after a marathon in male athletes.

    PubMed Central

    Laupheimer, M W; Perry, M; Benton, S; Malliaras, P; Maffulli, N

    2014-01-01

    Objective We investigated whether the inflammatory response and delayed onset of muscle soreness after a marathon are altered by resveratrol, a natural polyphenolic flavonoid antioxidant. Design: Double blind placebo-controlled randomised pilot study. Setting: London Marathon. Participants: Marathon race participants Interventions: 7 healthy male athletes were randomised to receive Resveratrol (600 mg Resveratrol daily for 7 days immediately before the marathon) or a placebo. Main Outcome Measurements: Blood samples taken 48 hours before and 18–32 hours after the marathon were analysed for white blood cell count (WBC) and C-reactive protein (CRP). A VAS score was taken at the same times as the blood samples to assess delayed onset muscle soreness. Results: There were no significant differences between the two groups in terms of changes occurring between pre- and post- tests for WBC, CRP or VAS. Conclusions: There were no differences in immune response or delayed onset muscle soreness between resveratrol and placebo after a marathon. Further investigations are needed with longer treatment time and higher doses, analysing additional parameters such interleukins for a possible effect of resveratrol on the inflammatory response due to extensive exercise. To avoid a type II error, 17 subjects in each group would be required. PMID:25147765

  14. The influence of an artificial playing surface on injury risk and perceptions of muscle soreness in elite Rugby Union.

    PubMed

    Williams, S; Trewartha, G; Kemp, S P T; Michell, R; Stokes, K A

    2016-01-01

    This prospective cohort study investigated the influence of an artificial playing surface on injury risk and perceptions of muscle soreness in elite English Premiership Rugby Union players. Time loss (from 39.5 matches) and abrasion (from 27 matches) injury risk was compared between matches played on artificial turf and natural grass. Muscle soreness was reported over the 4 days following one match played on each surface by 95 visiting players (i.e., normally play on natural grass surfaces). There was a likely trivial difference in the overall injury burden relating to time-loss injuries between playing surfaces [rate ratio = 1.01, 90% confidence interval (CI): 0.73-1.38]. Abrasions were substantially more common on artificial turf (rate ratio = 7.92, 90% CI: 4.39-14.28), although the majority of these were minor and only two resulted in any reported time loss. Muscle soreness was consistently higher over the 4 days following a match on artificial turf in comparison with natural grass, although the magnitude of this effect was small (effect sizes ranging from 0.26 to 0.40). These results suggest that overall injury risk is similar for the two playing surfaces, but further surveillance is required before inferences regarding specific injury diagnoses and smaller differences in overall injury risk can be made.

  15. Control of scabies, skin sores and haematuria in children in the Solomon Islands: another role for ivermectin.

    PubMed Central

    Lawrence, Gregor; Leafasia, Judson; Sheridan, John; Hills, Susan; Wate, Janet; Wate, Christine; Montgomery, Janet; Pandeya, Nirmala; Purdie, David

    2005-01-01

    OBJECTIVE: To assess the effects of a 3-year programme aimed at controlling scabies on five small lagoon islands in the Solomon Islands by monitoring scabies, skin sores, streptococcal skin contamination, serology and haematuria in the island children. METHODS: Control was achieved by treating almost all residents of each island once or twice within 2 weeks with ivermectin (160-250 microg/kg), except for children who weighed less than 15 kg and pregnant women, for whom 5% permethrin cream was used. Reintroduction of scabies was controlled by treating returning residents and visitors, whether or not they had evident scabies. FINDINGS: Prevalence of scabies dropped from 25% to less than 1% (P < 0.001); prevalence of sores from 40% to 21% (P < 0.001); streptococcal contamination of the fingers in those with and without sores decreased significantly (P = 0.02 and 0.047, respectively) and anti-DNase B levels decreased (P = 0.002). Both the proportion of children with haematuria and its mean level fell (P = 0.002 and P < 0.001, respectively). No adverse effects of the treatments were seen. CONCLUSION: The results show that ivermectin is an effective and practical agent in the control of scabies and that control reduces the occurrence of streptococcal skin disease and possible signs of renal damage in children. Integrating community-based control of scabies and streptococcal skin disease with planned programmes for controlling filariasis and intestinal nematodes could be both practical and produce great health benefits. PMID:15682247

  16. Melting in the FeOsbnd SiO2 system to deep lower-mantle pressures: Implications for subducted Banded Iron Formations

    NASA Astrophysics Data System (ADS)

    Kato, Chie; Hirose, Kei; Nomura, Ryuichi; Ballmer, Maxim D.; Miyake, Akira; Ohishi, Yasuo

    2016-04-01

    Banded iron formations (BIFs), consisting of layers of iron oxide and silica, are far denser than normal mantle material and should have been subducted and sunk into the deep lower mantle. We performed melting experiments on Fe2SiO4 from 26 to 131 GPa in a laser-heated diamond-anvil cell (DAC). The textural and chemical characterization of a sample recovered from the DAC revealed that SiO2 is the liquidus phase for the whole pressure range examined in this study. The chemical compositions of partial melts are very rich in FeO, indicating that the eutectic melt compositions in the FeOsbnd SiO2 binary system are very close to the FeO end-member. The eutectic temperature is estimated to be 3540 ± 150 K at the core-mantle boundary (CMB), which is likely to be lower than the temperature at the top of the core at least in the Archean and Paleoproterozoic eons, suggesting that subducted BIFs underwent partial melting in a thermal boundary layer above the CMB. The FeO-rich melts formed by partial melting of the BIFs were exceedingly dense and therefore migrated downward. We infer that such partial melts have caused iron enrichment in the bottom part of the mantle, which may have contributed to the formation of ultralow velocity zones (ULVZs) observed today. On the other hand, solid residues left after the segregation of the FeO-rich partial melts have been almost pure SiO2, and therefore buoyant in the deep lower mantle to be entrained in mantle upwellings. They have likely been stretched and folded repeatedly by mantle flow, forming SiO2 streaks within the mantle "marble cake". Mantle packages enhanced by SiO2 streaks may be the origin of seismic scatterers in the mid-lower mantle.

  17. Herbs and natural supplements in the prevention and treatment of delayed-onset muscle soreness

    PubMed Central

    Meamarbashi, Abbas

    2017-01-01

    Objective: Unaccustomed and intense eccentric exercise is a common cause of delayed-onset muscle soreness (DOMS). There are multiple remedies for the treatment of DOMS, but its clinical and laboratory pieces of evidence are scarce. Currently, the treatments proposed for DOMS are numerous and include pharmaceuticals, herbal remedies, stretching, massage, nutritional supplements, and other alternatives. To find a holistic treatment with effective pain relief and minimum side effects, complementary and alternative medicine, including herbal therapies, plays a main role. Methods: In this review, the existing published studies investigating the efficacy of herbal and natural supplementation therapies for the prevention or treatment of side effects, symptoms, and signs of DOMS are summarized. Results: Previous studies have documented the efficacy of herbal therapies to treat pain, inflammation, as well as laboratory and clinical side effects of DOMS. Conclusion: The use of herbs in DOMS seems safer and has lower side effects than pharmacotherapy. However, the potential for side effects and drug interactions should be considered. PMID:28265543

  18. Stress and body condition in a population of largemouth bass: implications for red-sore disease

    SciTech Connect

    Esch, G.W.; Hazen, T.C.

    1980-09-01

    The body conditions, K = 10/sup 5/(weight, g)/(standard length)/sup 3/, and various hematological characters were examined for largemouth bass (Micropterus salmoides) taken from Par Pond, a reservoir heated by effluent from a nuclear production reactor at the Savannah River Plant near Aiken, South Carolina. Largemouth bass with K less than 2.0 had significantly lower (P < 0.05) hematocrits, hemoglobin concentrations, total red blood cell counts, total white blood cell counts, and lymphocyte fractions, and significantly higher granulocyte fractions and cortisol concentrations, than those with K greater than 2.0; monocyte, thrombocyte, and reticulocyte fractions were not different between the two K-factor groupings. When data were pooled, all blood variables except the reticulocyte fraction were significantly correlated with K. Hematocrit, the lymphocyte fraction, and cortisol concentration account for 20.5% of the variation in K. These data support a previous hypothesis that elevated water temperature promotes stress. Stress within the Par Pond largemouth bass population may play an important role in the epizootiology of red-sore disease caused by the gram-negative bacterium, Aeromonas hydrophila.

  19. A review of nutritional intervention on delayed onset muscle soreness. Part I.

    PubMed

    Kim, Jooyoung; Lee, Joohyung

    2014-12-01

    This review is focused on the effect of nutritional intervention on delayed onset muscle soreness (DOMS) that occurs after exercise. In general, high force eccentric contractions and/or unaccustomed exercise result in DOMS attributed to reduction in performance such as muscle strength and range of motion (ROM) for both athletes and non-athletes. Nutritional intervention is one of the preventive or therapeutic ways to reduce DOMS. Previous research studies have suggested the following nutrition intervention: caffeine, omega-3 fatty acids, taurine, polyphenols, and so on. Nutritional intervention with these nutrients before and after exercise was reported to be effective in reducing DOMS. These nutritional interventions have also been reported to affect inflammatory responses and oxidative stress leading to DOMS reduction. However, other studies have reported that these nutritional interventions have no effect on DOMS. It is suggested that intake of proper nutrition intervention can effectively reduce DOMS after exercise and quickly help an athlete return to exercise or training program. In addition, nutritional intervention may help both athletes and non-athletes who engage in physical therapy or rehabilitative programs after surgery or any injurious events.

  20. Influence of fatigue, stress, muscle soreness and sleep on perceived exertion during submaximal effort.

    PubMed

    Haddad, Monoem; Chaouachi, Anis; Wong, Del P; Castagna, Carlo; Hambli, Mourad; Hue, Olivier; Chamari, Karim

    2013-07-02

    The aim of this study was to assess the effects of the Hooper's Index variations (i.e., self-ratings of fatigue, stress, delayed onset muscle soreness (DOMS), and sleep) on rating of perceived exertion during a 10 min submaximal exercise training session (RPE-10 min) and then check the stability and the internal consistency of RPE-10 min. Seventeen junior soccer players took part in this study. The individual Hooper's indices taken before each training session were correlated with RPE-10 min during a constant intensity and duration effort (10 min) using Pearson product moment correlation. Intraclass correlation (ICC) was used to assess the internal consistency of the RPE-10 min. All individual correlations between RPE-10 min and quality of sleep and quantity of fatigue, stress, and DOMS were non-significant (p>0.05). No significant correlations were resulted between RPE-10 min and Hooper's Index in all athletes. The ICC of RPE-10 min was 0.77 thus demonstrating internal consistency. The results of the present study demonstrated the objectivity and utility of RPE as a psychological tool for monitoring training during traditional soccer training. Therefore, the results of the present study suggest that fatigue, stress, DOMS and sleep are not major contributors of perceived exertion during traditional soccer training without excessive training loads. It seems that psychobiological factors other than fatigue, stress, DOMS and sleep may have mediated the 10 min exercise perceptual intensity.

  1. Central Projection of Pain Arising from Delayed Onset Muscle Soreness (DOMS) in Human Subjects

    PubMed Central

    Zimmermann, Katharina; Leidl, Caroline; Kaschka, Miriam; Carr, Richard W.; Terekhin, Pavel; Handwerker, Hermann O.; Forster, Clemens

    2012-01-01

    Delayed onset muscle soreness (DOMS) is a subacute pain state arising 24–48 hours after a bout of unaccustomed eccentric muscle contractions. Functional magnetic resonance imaging (fMRI) was used to examine the patterns of cortical activation arising during DOMS-related pain in the quadriceps muscle of healthy volunteers evoked by either voluntary contraction or physical stimulation. The painful movement or physical stimulation of the DOMS-affected thigh disclosed widespread activation in the primary somatosensory and motor (S1, M1) cortices, stretching far beyond the corresponding areas somatotopically related to contraction or physical stimulation of the thigh; activation also included a large area within the cingulate cortex encompassing posteroanterior regions and the cingulate motor area. Pain-related activations were also found in premotor (M2) areas, bilateral in the insular cortex and the thalamic nuclei. In contrast, movement of a DOMS-affected limb led also to activation in the ipsilateral anterior cerebellum, while DOMS-related pain evoked by physical stimulation devoid of limb movement did not. PMID:23056613

  2. A review of nutritional intervention on delayed onset muscle soreness. Part I

    PubMed Central

    Kim, Jooyoung; Lee, Joohyung

    2014-01-01

    This review is focused on the effect of nutritional intervention on delayed onset muscle soreness (DOMS) that occurs after exercise. In general, high force eccentric contractions and/or unaccustomed exercise result in DOMS attributed to reduction in performance such as muscle strength and range of motion (ROM) for both athletes and non-athletes. Nutritional intervention is one of the preventive or therapeutic ways to reduce DOMS. Previous research studies have suggested the following nutrition intervention: caffeine, omega-3 fatty acids, taurine, polyphenols, and so on. Nutritional intervention with these nutrients before and after exercise was reported to be effective in reducing DOMS. These nutritional interventions have also been reported to affect inflammatory responses and oxidative stress leading to DOMS reduction. However, other studies have reported that these nutritional interventions have no effect on DOMS. It is suggested that intake of proper nutrition intervention can effectively reduce DOMS after exercise and quickly help an athlete return to exercise or training program. In addition, nutritional intervention may help both athletes and non-athletes who engage in physical therapy or rehabilitative programs after surgery or any injurious events. PMID:25610818

  3. Gargling with sodium azulene sulfonate reduces the postoperative sore throat after intubation of the trachea.

    PubMed

    Ogata, Junchi; Minami, Kouichiro; Horishita, Takafumi; Shiraishi, Munehiro; Okamoto, Takashi; Terada, Tadanori; Sata, Takeyoshi

    2005-07-01

    Postoperative sore throat (POST) is a complication that remains to be resolved in patients undergoing endotracheal intubation. In this study, we investigated whether preoperative gargling with sodium 1,4-dimethyl-7-isopropylazulene-3-sulfonate monohydrate (sodium azulene sulfonate, Azunol) reduces POST after endotracheal intubation. Forty patients scheduled for elective surgery under general anesthesia were randomized into Azunol and control groups. In the Azunol group, patients gargled with 4 mg Azunol diluted with 100 mL tap water (40 microg/mL). In the control group, patients gargled with 100 mL of tap water. After emergence from general anesthesia, the patients with POST were counted and POST was evaluated using a verbal analog pain scale. There were no significant differences between the two groups by age, height, body weight, gender distribution, or duration of anesthesia and surgery. In the control group, 13 patients (65%) complained of POST, which remained 24 h later in nine patients (45%). In the Azunol group, five patients (25%) also complained of POST, which completely disappeared by 24 h later. The incidence of POST and verbal analog pain scale scores in the Azunol group decreased significantly compared with the control group. We demonstrated that gargling with Azunol effectively attenuated POST with no adverse reactions.

  4. The Influence of Oral L-Glutamine Supplementation on Muscle Strength Recovery and Soreness Following Unilateral Knee Extension Eccentric Exercise.

    PubMed

    Legault, Zachary; Bagnall, Nicholas; Kimmerly, Derek S

    2015-10-01

    The study aimed to examine the effects that L-glutamine supplementation has on quadriceps muscle strength and soreness ratings following eccentric exercise. It was hypothesized that glutamine ingestion would quicken the recovery rate of peak force production and decrease muscle soreness ratings over a 72-hr recovery period. Sixteen healthy participants (8♀/8♂; 22 ± 4 years) volunteered in a double-blind, randomized, placebo-controlled crossover study. Supplement conditions consisted of isoenergetic placebo (maltodextrin, 0.6 g·kg-1·day-1) and L-glutamine (0.3 g·kg-1·day-1 + 0.3 g·kg-1·day-1 maltodextrin) ingestion once per day over 72 hr. Knee extensor peak torque at 0°, 30°, and 180° per second and muscle soreness were measured before, immediately following, 24, 48, and 72 hr posteccentric exercise. Eccentric exercise consisted of 8 sets (10 repetitions/set) of unilateral knee extension at 125% maximum concentric force with 2-min rest intervals. L-glutamine resulted in greater relative peak torque at 180°/sec both immediately after (71 ± 8% vs. 66 ± 9%), and 72 hr (91 ± 8% vs. 86 ± 7%) postexercise (all, p < .01). In men, L-glutamine produced greater (p < .01) peak torques at 30°/ sec postexercise. Men also produced greater normalized peak torques at 30°/sec (Nm/kg) in the L-glutamine condition than women (all, p < .05). In the entire sample, L-glutamine resulted in lower soreness ratings at 24 (2.8 ± 1.2 vs. 3.4 ± 1.2), 48 (2.6 ± 1.4 vs. 3.9 ± 1.2), and 72 (1.7 ± 1.2 vs. 2.9 ± 1.3) hr postexercise (p < .01). The L-glutamine supplementation resulted in faster recovery of peak torque and diminished muscle soreness following eccentric exercise. The effect of L-glutamine on muscle force recovery may be greater in men than women.

  5. Diamond formation in the deep lower mantle: a high-pressure reaction of MgCO3 and SiO2

    PubMed Central

    Maeda, Fumiya; Ohtani, Eiji; Kamada, Seiji; Sakamaki, Tatsuya; Hirao, Naohisa; Ohishi, Yasuo

    2017-01-01

    Diamond is an evidence for carbon existing in the deep Earth. Some diamonds are considered to have originated at various depth ranges from the mantle transition zone to the lower mantle. These diamonds are expected to carry significant information about the deep Earth. Here, we determined the phase relations in the MgCO3-SiO2 system up to 152 GPa and 3,100 K using a double sided laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction. MgCO3 transforms from magnesite to the high-pressure polymorph of MgCO3, phase II, above 80 GPa. A reaction between MgCO3 phase II and SiO2 (CaCl2-type SiO2 or seifertite) to form diamond and MgSiO3 (bridgmanite or post-perovsktite) was identified in the deep lower mantle conditions. These observations suggested that the reaction of the MgCO3 phase II with SiO2 causes formation of super-deep diamond in cold slabs descending into the deep lower mantle. PMID:28084421

  6. The effect of pressure and excitation energy on the isotopic fractionation in the formation of ozone by discharge of O2. [in meteorites

    NASA Technical Reports Server (NTRS)

    Yang, Jongmann; Epstein, Samuel

    1987-01-01

    Isotopic fractionation processes in the formation of O3 by discharge (at 20 kV and 3 MHz) of O2 in a fused silica container at 77 K are investigated experimentally, with a focus on the effects of changes in the isotopic abundances in the predischarge O2, the O2 pressure, and the excitation energy on the isotope abundances in the postdischarge O2 and O3. The results are presented in extensive tables and graphs and characterized in detail, and good general agreement is found with data obtained using 60-kHz excitation (Yang and Epstein, 1987). It is shown that O-17 and O-18 enrichment of the residual O2 (when the predischarge gas is enriched) or of the O3 (when atmospheric isotope abundances are used) can occur independently of one another. It is inferred that the rate of anharmonic predissociation of vibrationally hot O3 depends on the symmetry and mass of the O3 molecules. The significance of the present findings for studies of anomalous oxygen isotope abundances in meteorites is indicated.

  7. Diamond formation in the deep lower mantle: a high-pressure reaction of MgCO3 and SiO2

    NASA Astrophysics Data System (ADS)

    Maeda, Fumiya; Ohtani, Eiji; Kamada, Seiji; Sakamaki, Tatsuya; Hirao, Naohisa; Ohishi, Yasuo

    2017-01-01

    Diamond is an evidence for carbon existing in the deep Earth. Some diamonds are considered to have originated at various depth ranges from the mantle transition zone to the lower mantle. These diamonds are expected to carry significant information about the deep Earth. Here, we determined the phase relations in the MgCO3-SiO2 system up to 152 GPa and 3,100 K using a double sided laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction. MgCO3 transforms from magnesite to the high-pressure polymorph of MgCO3, phase II, above 80 GPa. A reaction between MgCO3 phase II and SiO2 (CaCl2-type SiO2 or seifertite) to form diamond and MgSiO3 (bridgmanite or post-perovsktite) was identified in the deep lower mantle conditions. These observations suggested that the reaction of the MgCO3 phase II with SiO2 causes formation of super-deep diamond in cold slabs descending into the deep lower mantle.

  8. Compression Garments and Exercise: No Influence of Pressure Applied

    PubMed Central

    Beliard, Samuel; Chauveau, Michel; Moscatiello, Timothée; Cros, François; Ecarnot, Fiona; Becker, François

    2015-01-01

    Compression garments on the lower limbs are increasingly popular among athletes who wish to improve performance, reduce exercise-induced discomfort, and reduce the risk of injury. However, the beneficial effects of compression garments have not been clearly established. We performed a review of the literature for prospective, randomized, controlled studies, using quantified lower limb compression in order to (1) describe the beneficial effects that have been identified with compression garments, and in which conditions; and (2) investigate whether there is a relation between the pressure applied and the reported effects. The pressure delivered were measured either in laboratory conditions on garments identical to those used in the studies, or derived from publication data. Twenty three original articles were selected for inclusion in this review. The effects of wearing compression garments during exercise are controversial, as most studies failed to demonstrate a beneficial effect on immediate or performance recovery, or on delayed onset of muscle soreness. There was a trend towards a beneficial effect of compression garments worn during recovery, with performance recovery found to be improved in the five studies in which this was investigated, and delayed-onset muscle soreness was reportedly reduced in three of these five studies. There is no apparent relation between the effects of compression garments worn during or after exercise and the pressures applied, since beneficial effects were obtained with both low and high pressures. Wearing compression garments during recovery from exercise seems to be beneficial for performance recovery and delayed-onset muscle soreness, but the factors explaining this efficacy remain to be elucidated. Key points We observed no relationship between the effects of compression and the pressures applied. The pressure applied at the level of the lower limb by compression garments destined for use by athletes varies widely between

  9. Liquid-liquid miscibility gaps and hydrate formation in drug-water binary systems: pressure-temperature phase diagram of lidocaine and pressure-temperature-composition phase diagram of the lidocaine-water system.

    PubMed

    Ceolin, René; Barrio, Maria; Tamarit, Josep-Lluis; Veglio, Nestor; Perrin, Marc-Antoine; Espeau, Philippe

    2010-06-01

    The pressure-temperature (P-T) melting curve of lidocaine was determined (dP/dT = 3.56 MPa K(-1)), and the lidocaine-water system was investigated as a function of temperature and pressure. The lidocaine-water system exhibits a monotectic equilibrium at 321 K (ordinary pressure) whose temperature increases as the pressure increases until the two liquids become miscible. A hydrate, unstable at ordinary pressure, was shown to form, on increasing the pressure, from about 70 MPa at low temperatures (200-300 K). The thermodynamic conditions of its stability were inferred from the location of the three-phase equilibria involving the hydrate in the lidocaine-water pressure-temperature-mole fraction (P-T-x) diagram.

  10. Advanced Technologies for Monitoring CO2 Saturation and Pore Pressure in Geologic Formations: Linking the Chemical and Physical Effects to Elastic and Transport Properties

    SciTech Connect

    Mavko, G.; Vanorio, T.; Vialle, S.; Saxena, N.

    2014-03-31

    advection: because of an efficient mass transfer of reactants and products, the fluid remains acidic, far from thermodynamical equilibrium and the dissolution of calcite is important. These conclusions are consistent with the lab observations. Sandstones from the Tuscaloosa formation in Mississippi were also subjected to injection under representative in situ stress and pore pressure conditions. Again, both P- and S-wave velocities decreased with injection. Time-lapse SEM images indicated permanent changes induced in the sandstone microstructure by chamosite dissolution upon injection of CO2-rich brine. After injection, the sandstone showed an overall cleaner microstructure. Two main changes are involved: (a) clay dissolution between grains and at the grain contact and (b) rearrangement of grains due to compaction under pressure Theoretical and empirical models were developed to quantify the elastic changes associated with injection. Permanent changes to the rock frame resulted in seismic velocity-porosity trends that mimic natural diagenetic changes. Hence, when laboratory measurments are not available for a candidate site, these trends can be estimated from depth trends in well logs. New theoretical equations were developed to predict the changes in elastic moduli upon substitution of pore-filling material. These equations reduce to Gassmann’s equations for the case of constant frame properties, low seismic frequencies, and fluid changes in the pore space. The new models also predict the change dissolution or precipitation of mineral, which cannot be described with the conventional Gassmann theory.

  11. Inflation pressure effect on performance of air-filled wheelchair cushions.

    PubMed

    Krouskop, T A; Williams, R; Noble, P; Brown, J

    1986-02-01

    Air-filled wheelchair cushions are frequently used in the prevention of pressure sores. Their effectiveness in reducing interface pressures and in redistributing body weight (BW) appears dependent on their internal inflation pressure. This pilot study examines and defines this relationship. Interface pressures were measured with the TIPE (Texas Interface Pressure Evaluator) system for 14 subjects while sitting on each of three commercially available air-filled wheelchair cushions. This relationship between interface pressure and internal pressure was then determined for each of the three body-build categories. In each category the interface pressure displayed a higher degree of sensitivity to underinflation than to overinflation. A high correlation found between BW and internal air pressure (IAP), may be useful in the design of a customized pressure indicator system. The study documents the influence of IAP on seating pressure and supports the need for further research in the development of an indicator system that alerts users to under- or overinflation of the cushion.

  12. Alternating pressure mattresses: comfort and quality of sleep.

    PubMed

    Grindley, A; Acres, J

    Comfort is particularly important for patients with terminal illness where the priority is to maximize quality of life. Equally important is effective pressure area care, as such patients are at high risk of developing pressure sores because of their poor general condition (Bale and Regnard, 1995). The present randomized controlled study set in a hospice focused on the development of methodology for assessing patient comfort and quality of sleep and used this to compare two widely used, alternating air pressure mattresses (the Nimbus II and the Pegasus Airwave). The Nimbus II mattress performed consistently better than the Pegasus Airwave in terms of patient comfort and quality of sleep. Features of the Nimbus II that may explain its better performance include less extreme changes in pressure, lower peak inflation pressures and the ability to automatically vary the pressure to suit the patient's position and weight.

  13. The Effects of Pre-Exercise Ginger Supplementation on Muscle Damage and Delayed Onset Muscle Soreness.

    PubMed

    Matsumura, Melissa D; Zavorsky, Gerald S; Smoliga, James M

    2015-06-01

    Ginger possesses analgesic and pharmacological properties mimicking non-steroidal antiinflammatory drugs. We aimed to determine if ginger supplementation is efficacious for attenuating muscle damage and delayed onset muscle soreness (DOMS) following high-intensity resistance exercise. Following a 5-day supplementation period of placebo or 4 g ginger (randomized groups), 20 non-weight trained participants performed a high-intensity elbow flexor eccentric exercise protocol to induce muscle damage. Markers associated with muscle damage and DOMS were repeatedly measured before supplementation and for 4 days following the exercise protocol. Repeated measures analysis of variance revealed one repetition maximum lift decreased significantly 24 h post-exercise in both groups (p < 0.005), improved 48 h post-exercise only in the ginger group (p = 0.002), and improved at 72 (p = 0.021) and 96 h (p = 0.044) only in the placebo group. Blood creatine kinase significantly increased for both groups (p = 0.015) but continued to increase only in the ginger group 72 (p = 0.006) and 96 h (p = 0.027) post-exercise. Visual analog scale of pain was significantly elevated following eccentric exercise (p < 0.001) and was not influenced by ginger. In conclusion, 4 g of ginger supplementation may be used to accelerate recovery of muscle strength following intense exercise but does not influence indicators of muscle damage or DOMS.

  14. Phytochemical, Antimicrobial, and Toxicological Evaluation of Traditional Herbs Used to Treat Sore Throat

    PubMed Central

    Mehreen, Arifa; Waheed, Muzzamil; Liaqat, Iram; Arshad, Najma

    2016-01-01

    The in vitro antibacterial activities of 29 traditional medicinal plants used in respiratory ailments were assessed on multidrug resistant Gram-positive and Gram-negative bacteria isolated from the sore throat patients and two reference strains. The methanolic, n-hexane, and aqueous extracts were screened by the agar well diffusion assay. Bioactive fractions of effective extracts were identified on TLC coupled with bioautography, while their toxicity was determined using haemolytic assay against human erythrocytes. Qualitative and quantitative phytochemical analysis of effective extracts was also performed. Methanolic extract of 18 plants showed antimicrobial activity against test strains. Adhatoda vasica (ZI = 17–21 mm, MIC: 7.12–62.5 μg/mL), Althaea officinalis (ZI = 16–20 mm, MIC: 15.62–31.25 μg/mL), Cordia latifolia (ZI = 16–20 mm, MIC: 12.62–62.5 μg/mL), Origanum vulgare (ZI = 20–22 mm, MIC: 3–15.62 μg/mL), Thymus vulgaris (ZI = 21–25 mm, MIC: 7.81–31.25 μg/mL), and Ziziphus jujuba (ZI = 14–20 mm, MIC: 7.81–31.25 μg/mL) showed significant antibacterial activity. Alkaloid fractions of Adhatoda vasica, Cordia latifolia, and Origanum vulgare and flavonoid fraction of the Althaea officinalis, Origanum vulgare, Thymus Vulgaris, and Ziziphus jujuba exhibited antimicrobial activity. Effective plant extracts show 0.93–0.7% erythrocyte haemolysis. The results obtained from this study provide a scientific rationale for the traditional use of these herbs and laid the basis for future studies to explore novel antimicrobial compounds. PMID:27429983

  15. Ice‐water immersion and delayed‐onset muscle soreness: a randomised controlled trial

    PubMed Central

    Sellwood, Kylie Louise; Brukner, Peter; Williams, David; Nicol, Alastair; Hinman, Rana

    2007-01-01

    Objective To determine if ice‐water immersion after eccentric quadriceps exercise minimises the symptoms of delayed‐onset muscle soreness (DOMS). Design A prospective randomised double‐blind controlled trial was undertaken. 40 untrained volunteers performed an eccentric loading protocol with their non‐dominant leg. Interventions Participants were randomised to three 1‐min immersions in either ice water (5±1°C) or tepid water (24°C). Main outcome measures Pain and tenderness (visual analogue scale), swelling (thigh circumference), function (one‐legged hop for distance), maximal isometric strength and serum creatine kinase (CK) recorded at baseline, 24, 48 and 72 h after exercise. Changes in outcome measures over time were compared to determine the effect of group allocation using independent t tests or Mann–Whitney U tests. Results No significant differences were observed between groups with regard to changes in most pain parameters, tenderness, isometric strength, swelling, hop‐for‐distance or serum CK over time. There was a significant difference in pain on sit‐to‐stand at 24 h, with the intervention group demonstrating a greater increase in pain than the control group (median change 8.0 vs 2.0 mm, respectively, p = 0.009). Conclusions The protocol of ice‐water immersion used in this study was ineffectual in minimising markers of DOMS in untrained individuals. This study challenges the wide use of this intervention as a recovery strategy by athletes. PMID:17261562

  16. Manual therapy ameliorates delayed-onset muscle soreness and alters muscle metabolites in rats.

    PubMed

    Urakawa, Susumu; Takamoto, Kouichi; Nakamura, Tomoya; Sakai, Shigekazu; Matsuda, Teru; Taguchi, Toru; Mizumura, Kazue; Ono, Taketoshi; Nishijo, Hisao

    2015-02-01

    Delayed-onset muscle soreness (DOMS) can be induced by lengthening contraction (LC); it can be characterized by tenderness and movement-related pain in the exercised muscle. Manual therapy (MT), including compression of exercised muscles, is widely used as physical rehabilitation to reduce pain and promote functional recovery. Although MT is beneficial for reducing musculoskeletal pain (i.e. DOMS), the physiological mechanisms of MT remain unclear. In the present study, we first developed an animal model of MT in DOMS; LC was applied to the rat gastrocnemius muscle under anesthesia, which induced mechanical hyperalgesia 2-4 days after LC. MT (manual compression) ameliorated mechanical hyperalgesia. Then, we used capillary electrophoresis time-of-flight mass spectroscopy (CE-TOFMS) to investigate early effects of MT on the metabolite profiles of the muscle experiencing DOMS. The rats were divided into the following three groups; (1) normal controls, (2) rats with LC application (LC group), and (3) rats undergoing MT after LC (LC + MT group). According to the CE-TOFMS analysis, a total of 171 metabolites were detected among the three groups, and 19 of these metabolites were significant among the groups. Furthermore, the concentrations of eight metabolites, including branched-chain amino acids, carnitine, and malic acid, were significantly different between the LC + MT and LC groups. The results suggest that MT significantly altered metabolite profiles in DOMS. According to our findings and previous data regarding metabolites in mitochondrial metabolism, the ameliorative effects of MT might be mediated partly through alterations in metabolites associated with mitochondrial respiration.

  17. Delayed-onset muscle soreness: a pilot study to assess analgesic study design features.

    PubMed

    Singla, Neil; Desjardins, Paul J; Cosca, Evelyn B; Parulan, Cherri; Arriaga, Anne; Poole, Kelly C; Batz, Dan M; Chang, Phoebe D

    2015-06-01

    Based on a thorough review of the available literature in the delayed-onset muscle soreness (DOMS) model, we identified multiple study design characteristics that are considered to be normative in acute pain research but have not been followed in a majority of published DOMS experiments. We designed an analgesic investigation using the DOMS model that both complied with current scientifically accepted standards for the conduct of analgesic studies and demonstrated reasonable assay sensitivity. This randomized, double-blind, placebo-controlled within-subject study compared the efficacy of topical diclofenac sodium 1% with a matching placebo in reducing pain associated with DOMS. After exercise, subjects reporting DOMS received topical diclofenac sodium gel 1% (DSG 1%) applied to one leg and placebo to the other every 6 hours for 48 hours. Pain intensity was assessed at rest, upon standing, and when walking in the 48 hours after initial drug application (T0). The primary end point was the reduction in pain intensity (SPID 24) on walking. Subjects receiving DSG 1% had less pain while walking compared with those receiving placebo at 24 hours (SPID 24 = 34.9 [22.9] and 23.6 [19.4], respectively; P = 0.032). This investigation used experimental techniques that have been vetted in the field of exercise physiology and superimposed techniques that are considered to be best practice in the field of analgesic research. Over time and with the help of colleagues in both fields of study, similar investigations will validate design features that impact the assay sensitivity of analgesic end points in DOMS models. In addition, the study confirmed the analgesic efficacy of topical DSG 1% over placebo in subjects experiencing DOMS.

  18. Temporal Pattern of the Repeated Bout Effect of Eccentric Exercise on Delayed-Onset Muscle Soreness

    PubMed Central

    Cleary, Michelle A.; Kimura, Iris F.; Sitler, Michael R.; Kendrick, Zebulon V.

    2002-01-01

    Objective: To determine the temporal pattern of the repeated bout effect of eccentric exercise on perceived pain and muscular tenderness associated with delayed-onset muscle soreness (DOMS). Design and Setting: Subjects completed 2 identical eccentric exercise bouts separated by 6, 7, 8, or 9 weeks. The experiment was conducted in a biokinetics research laboratory. Subjects: Sixteen male and 15 female untrained subjects (age = 24.59 ± 4.42 years, height = 171.71 ± 7.81 cm, weight = 73.00 ± 11.20 kg). Measurements: Two physiologic characteristics of DOMS were measured immediately before and 0, 24, 48, and 72 hours after each eccentric exercise bout. Perceived pain was measured using a visual analog scale (VAS), and muscular tenderness was measured using a punctate tenderness gauge (PTG). Results: Two 4 × 2 × 5 (group × bout × time) analyses of variance with repeated measures on the bout and time factors were performed on the VAS and PTG data. Significant (P < .05) main effects were found for group, bout, and time for the VAS and the PTG data. No significant interactions were detected. Post hoc analysis revealed significantly less perceived pain for the 9-week group than the 8-week group. The 7-week group had significantly less and the 8-week group had significantly more muscular tenderness than any other group. Perceived pain and muscular tenderness were significantly less after exercise bout 2 than after exercise bout 1. All subjects had significantly less perceived pain and muscular tenderness pre-exercise than 0 and 24 hours after the eccentric exercise bouts. Conclusions: An effective prophylaxis for perceived pain and muscular tenderness associated with DOMS is the performance of an eccentric exercise bout 6 to 9 weeks before a similar exercise bout. PMID:12937441

  19. COLD VRS HEAT AFTER EXERCISE- IS THERE A CLEAR WINNER FOR MUSCLE SORENESS.

    PubMed

    Petrofsky, Jerrold; Khowailed, Iman Akef; Lee, Haneul; Berk, Lee; Bains, Gurinder; Akerkar, Siddhesh; Shah, Jinal; Al-Dabbak, Fuad; Laymon, Mike

    2015-08-14

    Due to the differences in the exercise type, temperature and timing of the use of cold and heat after exercise in different studies, there is no clear conclusion as to the efficacy of either modality on reducing delayed onset muscle soreness. One hundred subjects at similar fitness levels were examined. They accomplished leg squats for 15 minutes and heat and cold were applied after or 24 hours after exercise using ThermaCare heat or cold wraps. Measurements obtained were strength, the force to passively move the knee, analog visual pain scales, and blood myoglobin. Control subjects lost 24% strength after exercise. Subjects with heat or cold just after exercise only lost 4% strength (p<0.01). Cold applied after 24 hours was better than heat at 24 for strength recovery. Heat or cold applied after exercise was significantly better to prevent elastic tissue damage (p<0.01) while heat and cold immediate after exercise caused no loss in muscle myoglobin whereas heat or cold after 24 hours showed no less muscle damage from myoglobin than control subjects. Myoglobin in the control and heat and cold 24 groups averaged 135.1% of the baseline data but averaged 106.1% of baseline in the heat and cold immediate groups. For reducing pain, control subjects showed a significant amount of pain the days after exercise. But cold immediately after exercise or 24 hours later was superior to heat in reducing pain. In conclusion, both cold and heat appear to be efficacious in reducing muscle damage after exercise.

  20. TRPV1 and TRPV4 play pivotal roles in delayed onset muscle soreness.

    PubMed

    Ota, Hiroki; Katanosaka, Kimiaki; Murase, Shiori; Kashio, Makiko; Tominaga, Makoto; Mizumura, Kazue

    2013-01-01

    Unaccustomed strenuous exercise that includes lengthening contraction (LC) often causes tenderness and movement related pain after some delay (delayed-onset muscle soreness, DOMS). We previously demonstrated that nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) are up-regulated in exercised muscle through up-regulation of cyclooxygenase (COX)-2, and they sensitized nociceptors resulting in mechanical hyperalgesia. There is also a study showing that transient receptor potential (TRP) ion channels are involved in DOMS. Here we examined whether and how TRPV1 and/or TRPV4 are involved in DOMS. We firstly evaluated a method to measure the mechanical withdrawal threshold of the deep tissues in wild-type (WT) mice with a modified Randall-Selitto apparatus. WT, TRPV1-/- and TRPV4-/- mice were then subjected to LC. Another group of mice received injection of murine NGF-2.5S or GDNF to the lateral gastrocnemius (LGC) muscle. Before and after these treatments the mechanical withdrawal threshold of LGC was evaluated. The change in expression of NGF, GDNF and COX-2 mRNA in the muscle was examined using real-time RT-PCR. In WT mice, mechanical hyperalgesia was observed 6-24 h after LC and 1-24 h after NGF and GDNF injection. LC induced mechanical hyperalgesia neither in TRPV1-/- nor in TRPV4-/- mice. NGF injection induced mechanical hyperalgesia in WT and TRPV4-/- mice but not in TRPV1-/- mice. GDNF injection induced mechanical hyperalgesia in WT but neither in TRPV1-/- nor in TRPV4-/- mice. Expression of NGF and COX-2 mRNA was significantly increased 3 h after LC in all genotypes. However, GDNF mRNA did not increase in TRPV4-/- mice. These results suggest that TRPV1 contributes to DOMS downstream (possibly at nociceptors) of NGF and GDNF, while TRPV4 is located downstream of GDNF and possibly also in the process of GDNF up-regulation.

  1. Cold Vs. Heat After Exercise-Is There a Clear Winner for Muscle Soreness.

    PubMed

    Petrofsky, Jerrold S; Khowailed, Iman Akef; Lee, Haneul; Berk, Lee; Bains, Gurinder S; Akerkar, Siddhesh; Shah, Jinal; Al-Dabbak, Fuad; Laymon, Mike S

    2015-11-01

    Because of the differences in the exercise type, temperature, and timing of the use of cold and heat after exercise in different studies, there is no clear conclusion as to the efficacy of either modality on reducing delayed onset muscle soreness. One hundred subjects at similar fitness levels were examined. They accomplished leg squats for 15 minutes and heat and cold were applied after or 24 hours after exercise using ThermaCare heat or cold wraps. Measurements obtained were strength, the force to passively move the knee, analog visual pain scales, and blood myoglobin. Control subjects lost 24% strength after exercise. Subjects with heat or cold just after exercise only lost 4% strength (p < 0.01). For strength recovery, cold applied after 24 hours was better than heat at 24 hours. Heat or cold applied after exercise was significantly better to prevent elastic tissue damage (p < 0.01), whereas heat and cold immediately after exercise caused no loss in muscle myoglobin and heat or cold after 24 hours showed no less muscle damage from myoglobin than in control subjects. Myoglobin in the control and heat and cold 24-hour groups averaged 135.1% of the baseline data but averaged 106.1% of baseline in the immediate heat and cold groups. For reducing pain, control subjects showed a significant amount of pain the days after exercise. But cold immediately after exercise or 24 hours later was superior to heat in reducing pain. In conclusion, both cold and heat appear to be efficacious in reducing muscle damage after exercise.

  2. Manual therapy ameliorates delayed-onset muscle soreness and alters muscle metabolites in rats

    PubMed Central

    Urakawa, Susumu; Takamoto, Kouichi; Nakamura, Tomoya; Sakai, Shigekazu; Matsuda, Teru; Taguchi, Toru; Mizumura, Kazue; Ono, Taketoshi; Nishijo, Hisao

    2015-01-01

    Delayed-onset muscle soreness (DOMS) can be induced by lengthening contraction (LC); it can be characterized by tenderness and movement-related pain in the exercised muscle. Manual therapy (MT), including compression of exercised muscles, is widely used as physical rehabilitation to reduce pain and promote functional recovery. Although MT is beneficial for reducing musculoskeletal pain (i.e. DOMS), the physiological mechanisms of MT remain unclear. In the present study, we first developed an animal model of MT in DOMS; LC was applied to the rat gastrocnemius muscle under anesthesia, which induced mechanical hyperalgesia 2–4 days after LC. MT (manual compression) ameliorated mechanical hyperalgesia. Then, we used capillary electrophoresis time-of-flight mass spectroscopy (CE-TOFMS) to investigate early effects of MT on the metabolite profiles of the muscle experiencing DOMS. The rats were divided into the following three groups; (1) normal controls, (2) rats with LC application (LC group), and (3) rats undergoing MT after LC (LC + MT group). According to the CE-TOFMS analysis, a total of 171 metabolites were detected among the three groups, and 19 of these metabolites were significant among the groups. Furthermore, the concentrations of eight metabolites, including branched-chain amino acids, carnitine, and malic acid, were significantly different between the LC + MT and LC groups. The results suggest that MT significantly altered metabolite profiles in DOMS. According to our findings and previous data regarding metabolites in mitochondrial metabolism, the ameliorative effects of MT might be mediated partly through alterations in metabolites associated with mitochondrial respiration. PMID:25713324

  3. Delayed-onset muscle soreness: a pilot study to assess analgesic study design features

    PubMed Central

    Singla, Neil; Desjardins, Paul J.; Cosca, Evelyn B.; Parulan, Cherri; Arriaga, Anne; Poole, Kelly C.; Batz, Dan M.; Chang, Phoebe D.

    2015-01-01

    Abstract Based on a thorough review of the available literature in the delayed-onset muscle soreness (DOMS) model, we identified multiple study design characteristics that are considered to be normative in acute pain research but have not been followed in a majority of published DOMS experiments. We designed an analgesic investigation using the DOMS model that both complied with current scientifically accepted standards for the conduct of analgesic studies and demonstrated reasonable assay sensitivity. This randomized, double-blind, placebo-controlled within-subject study compared the efficacy of topical diclofenac sodium 1% with a matching placebo in reducing pain associated with DOMS. After exercise, subjects reporting DOMS received topical diclofenac sodium gel 1% (DSG 1%) applied to one leg and placebo to the other every 6 hours for 48 hours. Pain intensity was assessed at rest, upon standing, and when walking in the 48 hours after initial drug application (T0). The primary end point was the reduction in pain intensity (SPID 24) on walking. Subjects receiving DSG 1% had less pain while walking compared with those receiving placebo at 24 hours (SPID 24 = 34.9 [22.9] and 23.6 [19.4], respectively; P = 0.032). This investigation used experimental techniques that have been vetted in the field of exercise physiology and superimposed techniques that are considered to be best practice in the field of analgesic research. Over time and with the help of colleagues in both fields of study, similar investigations will validate design features that impact the assay sensitivity of analgesic end points in DOMS models. In addition, the study confirmed the analgesic efficacy of topical DSG 1% over placebo in subjects experiencing DOMS. PMID:25633158

  4. [Are antioxidant supplements effective in reducing delayed onset muscle soreness? A systematic review].

    PubMed

    Candia-Luján, Ramón; De Paz Fernández, José Antonio; Costa Moreira, Osvaldo

    2014-10-05

    Introducción: En los últimos años los suplementos antioxidantes han cobrado popularidad para contrarrestar los efectos de los radicales libres y los síntomas del daño muscular, entre los que se encuentra el dolor muscular tardío (DMT). Objetivo: realizar una revisión sistemática en diferentes bases de datos para conocer los efectos de los suplementos antioxidantes sobre el DMT. Método: Se llevó a cabo una búsqueda en las bases de datos; Cochrane Library, Pubmed, Scopus y SportDiscus y la Web Of Science (WOS). Las palabras y acrónimos usados fueron; Delayed onset muscle soreness, exercise induced muscle damage, DOMS, EIMD, antioxidant y oxidative stress. Resultados: Se identificaron 54 artículos de los cuales se recuperaron 48, todos ellos en inglés, 17 relacionados con la vitamina C y E, catorce corresponden a suplementos polifenòlicos, once a otros suplementos antioxidantes y seis a suplementos comerciales todos ellos usados para combatir, entre otras variables, el DMT. Conclusiones: Tanto las vitaminas como los suplementos comerciales presentan baja efectividad en la disminución del DMT, mientras que los polifenoles y otros suplementos antioxidantes muestran entre moderada y buena efectividad en el combate al DMT. Sin embargo, gran parte de los estudios presentan efectividad en la disminución de otros síntomas del daño muscular además de ayudar en la recuperación postejercicio.

  5. Basic Equations in Statics and Kinetics of Protein Polymerization and the Mechanism of the Formation and Dissociation of Amyloid Fibrils Revealed by Pressure Perturbation.

    PubMed

    Tachibana, Hideki

    2015-01-01

    Studies of the pressure-dissociation of several amyloid or amyloid-like fibrils have shown that the fibril state is considerably voluminous. Quantitative characterization of the protein fibrillation reaction with respect to volumetric parameters is necessary to elucidate mechanisms of amyloid fibrillation in molecular terms such as protein cavity and hydration. Here we discuss, firstly, basic equations in statics and kinetics of protein polymerization as employed to obtain thermodynamic, volumetric, and kinetic parameters. Equilibrium treatment of the reactions with the scheme such as one-step polymerization, linear-association polymerization, or nucleation-dependent polymerization, and kinetic treatment of seeded linear-polymerization or spontaneous nucleation-elongation polymerization are described. In particular we will detail kinetics of the dissociation of fibrils which have been produced under the linear-association mechanism and therefore the length-distribution of which conforms to a geometric sequence in the degree of polymerization with a common ratio r, which is less than, and usually very close to, unity. In this case, an observed macroscopic rate of dissociation is shown to be a product of the microscopic elementary dissociation rate constant and a factor (1-r), extremely reduced compared with the intrinsic elementary rate. Secondly, we discuss protein conformational states in fibrillogenesis with molecular and volumetric observations reported, such as the unfolded state responsible for the association with seeds and the extension of amyloid fibrils, the transition state in which protein cavity formation and dehydration occur to intermediate levels, and the fibril state in which they occur to final respective levels which, in some cases, depend on the maturity of the fibril.

  6. The effects of ice massage, ice massage with exercise, and exercise on the prevention and treatment of delayed onset muscle soreness.

    PubMed

    Isabell, W K; Durrant, E; Myrer, W; Anderson, S

    1992-01-01

    We investigated the effects of ice massage, ice massage with exercise, and exercise on the prevention and treatment of delayed onset muscle soreness (DOMS). Twenty-two subjects were randomly assigned to one of four groups. Preexercise measures were recorded for range of motion (ROM), strength, perceived soreness, and serum creatine kinase (CK) levels. Subjects performed up to 300 concentric/eccentric contractions of the elbow flexors with 90% of their 10 repetition maximum to induce muscle soreness. Dependent variables were assessed at 2, 4, 6, 24, 48, 72, 96, and 120 hours postexercise. Significant differences occurred in all variables with respect to time (ANOVA(p<.05)). However, no significant mode of treatment, or mode of treatment/assessment time interaction was present. Decreases in range of motion and flexion strength correspond with increases in perceived soreness. The nonsignificant mode of treatment/assessment time interaction suggests that the use of ice massage, ice massage with exercise, or exercise alone is not effective in significantly reducing the symptoms of delayed onset muscle soreness. In fact, though not statistically significant, the pattern of the data suggested the use of ice in the treatment of DOMS may be contraindicated. Further investigation is recommended.

  7. [Home visiting nursing care for a terminal stage cancer patient with bed sore--coordination through exchanging of advice request memo as a useful tool].

    PubMed

    Sugihara, Sachiko; Yamada, Mai; Tayoshi, Mayumi; Kitamikado, Hatsue; Nakajima, Kazuyo; Konno, Hitomi; Akaeda, Kazuko; Yagishita, Toshiyuki; Oka, Yoichi

    2010-12-01

    Visiting nursing care service was provided to a 40s female patient, who had a terminal cancer with bed sore around the sacred bones. We started the nursing service when the patient was still cared at hospital. The nursing service we provided was coordinated by the certified nurse specialized in skin and excrement care and home visiting nurse. A smooth home care transition was resulted because of the coordination provided by the two nurses. We started coaching the family while the patient was still at the hospital with a home care instruction manual until the patient was discharged. All in all, the patient and her family were at ease with two nurses' coordinated efforts. Since the patient was cared at home, her bed sore problem got worse due to an absence of caregiver. In order to solve the bed sore problem, the visiting nurse took pictures of peeled adhesive patch and the bed sore around the sacred bones to show and consult with the certified nurse. With the advice from the certified nurse, the home visiting nurse was able to care the bed sore problem manageable in size. From this experience, we learned that a proper communication channel, in this case an advice request memo exchange, between the certified nurse and visiting nurse was a useful tool for both sides in order to properly assess the patient's medical care needs.

  8. The Effects of Ice Massage, Ice Massage with Exercise, and Exercise on the Prevention and Treatment of Delayed Onset Muscle Soreness

    PubMed Central

    Isabell, William Kirk; Durrant, Earlene; Myrer, William; Anderson, Shauna

    1992-01-01

    We investigated the effects of ice massage, ice massage with exercise, and exercise on the prevention and treatment of delayed onset muscle soreness (DOMS). Twenty-two subjects were randomly assigned to one of four groups. Preexercise measures were recorded for range of motion (ROM), strength, perceived soreness, and serum creatine kinase (CK) levels. Subjects performed up to 300 concentric/eccentric contractions of the elbow flexors with 90% of their 10 repetition maximum to induce muscle soreness. Dependent variables were assessed at 2, 4, 6, 24, 48, 72, 96, and 120 hours postexercise. Significant differences occurred in all variables with respect to time (ANOVA(p<.05)). However, no significant mode of treatment, or mode of treatment/assessment time interaction was present. Decreases in range of motion and flexion strength correspond with increases in perceived soreness. The nonsignificant mode of treatment/assessment time interaction suggests that the use of ice massage, ice massage with exercise, or exercise alone is not effective in significantly reducing the symptoms of delayed onset muscle soreness. In fact, though not statistically significant, the pattern of the data suggested the use of ice in the treatment of DOMS may be contraindicated. Further investigation is recommended. PMID:16558163

  9. Comparing the effect of ketamine and benzydamine gargling with placebo on post-operative sore throat: A randomized controlled trial

    PubMed Central

    Faiz, Seyed Hamid Reza; Rahimzadeh, Poupak; Poornajafian, Alireza; Nikzad, Naghme

    2014-01-01

    Background: Air way intubation for general anesthesia usually leads to sore throat after surgery. Ketamine plays an important role to block a number of receptors related to pain. Benzydamine hydrochloride is a non-steroidal anti-inflammatory drug that has been used to improve oropharyngeal disorders. In this study, it was intended to compare the effect of gargling different solutions before the surgery on post-operative sore throat (POST) in patients who underwent general anesthesia for hysterectomy. Materials and Methods: A total of 60 patients who underwent the elective hysterectomy were entered to the randomized controlled trial regarding to the eligibility criteria. Patients were simply randomly allocated to three groups and received one code. Every code was representative for a specific drug: 20 cc normal saline (control group) or 1.5 mg benzydamine in 20 cc solution or 20 mg ketamine in 20 cc solutions. All the research teams were blinded to the received solutions. POST was evaluated with numerical rating scale. The data were entered to SPSS software and analysis of variance (ANOVA) and Kruskal-Wallis one-way analysis of variance test, were performed. Results: The mean ages of ketamine, benzydamine, and normal saline recipients were not significantly different. The trend of the severity of sore throat during the first 24 h after the operation in ketamine recipients was significantly lower than the other two groups (P < 0.001). Conclusion: The pain scale after surgery was reduced by using both ketamine and benzydamine, but the ketamine effect was more noticeable. PMID:25371873

  10. Effects of winter military training on energy balance, whole-body protein balance, muscle damage, soreness, and physical performance.

    PubMed

    Margolis, Lee M; Murphy, Nancy E; Martini, Svein; Spitz, Marissa G; Thrane, Ingjerd; McGraw, Susan M; Blatny, Janet-Martha; Castellani, John W; Rood, Jennifer C; Young, Andrew J; Montain, Scott J; Gundersen, Yngvar; Pasiakos, Stefan M

    2014-12-01

    Physiological consequences of winter military operations are not well described. This study examined Norwegian soldiers (n = 21 males) participating in a physically demanding winter training program to evaluate whether short-term military training alters energy and whole-body protein balance, muscle damage, soreness, and performance. Energy expenditure (D2(18)O) and intake were measured daily, and postabsorptive whole-body protein turnover ([(15)N]-glycine), muscle damage, soreness, and performance (vertical jump) were assessed at baseline, following a 4-day, military task training phase (MTT) and after a 3-day, 54-km ski march (SKI). Energy intake (kcal·day(-1)) increased (P < 0.01) from (mean ± SD (95% confidence interval)) 3098 ± 236 (2985, 3212) during MTT to 3461 ± 586 (3178, 3743) during SKI, while protein (g·kg(-1)·day(-1)) intake remained constant (MTT, 1.59 ± 0.33 (1.51, 1.66); and SKI, 1.71 ± 0.55 (1.58, 1.85)). Energy expenditure increased (P < 0.05) during SKI (6851 ± 562 (6580, 7122)) compared with MTT (5480 ± 389 (5293, 5668)) and exceeded energy intake. Protein flux, synthesis, and breakdown were all increased (P < 0.05) 24%, 18%, and 27%, respectively, during SKI compared with baseline and MTT. Whole-body protein balance was lower (P < 0.05) during SKI (-1.41 ± 1.11 (-1.98, -0.84) g·kg(-1)·10 h) than MTT and baseline. Muscle damage and soreness increased and performance decreased progressively (P < 0.05). The physiological consequences observed during short-term winter military training provide the basis for future studies to evaluate nutritional strategies that attenuate protein loss and sustain performance during severe energy deficits.

  11. Grapevine species from varied native habitats exhibit differences in embolism formation/repair associated with leaf gas exchange and root pressure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drought induces xylem embolism formation, but grapevines can refill blocked conduits to restore transport capacity. It is unknown whether vulnerability to embolism formation and ability to repair differ among grapevine species. We analyzed in vivo embolism formation and repair using x-ray microtomog...

  12. Ascorbic acid supplementation does not attenuate post-exercise muscle soreness following muscle-damaging exercise but may delay the recovery process.

    PubMed

    Close, Graeme L; Ashton, Tony; Cable, Tim; Doran, Dominic; Holloway, Chris; McArdle, Frank; MacLaren, Don P M

    2006-05-01

    Exercise involving lengthening muscle actions, such as downhill running, results in delayed onset muscle soreness (DOMS), which may be attributable to reactive oxygen species (ROS). Although exercise causes oxidative stress, any link between ROS and DOMS remains speculative. There is emerging evidence to suggest that ROS play an important physiological role, assisting in the recovery process and protecting the cell from future damage; however, this has not been fully established. Despite this uncertainty as to the precise role of ROS, attempts to prevent post-exercise ROS production through antioxidant intervention are still common. The study investigated the effects of ascorbic acid supplementation on ROS production and DOMS following downhill running. Subjects were assigned to two groups. The ascorbic acid group (group AA) received 1 g ascorbic acid 2 h pre-, and for 14 d post-downhill running, whilst the placebo group (Pl group) received a placebo. Blood samples were drawn pre-supplement, pre- and post-exercise, and then 1, 2, 3, 4, 7 and 14 d post-exercise for analysis of ascorbate, malonaldehyde and total glutathione. DOMS was assessed using a visual analogue scale and pressure algometry. Muscle function was assessed using isokinetic dynamometry. Plasma ascorbate was elevated throughout in group AA compared with the Pl group. Downhill running resulted in DOMS in both groups. Muscle function was impaired post-exercise in both groups, although a delayed recovery was noted in group AA. Malonaldehyde increased 4 d post-exercise in the Pl group only. Ascorbic acid supplementation attenuates ROS production following downhill running, without affecting DOMS. Furthermore, ascorbic acid supplementation may inhibit the recovery of muscle function.

  13. Dehydration and Symptoms of Delayed-Onset Muscle Soreness in Normothermic Men

    PubMed Central

    Cleary, Michelle A; Sitler, Michael R; Kendrick, Zebulon V

    2006-01-01

    Context: A dehydrated individual who performs eccentric exercise may exacerbate skeletal muscle damage, leading to structural, contractile, and enzymatic protein denaturation, in addition to the myofiber and connective damage resulting from the eccentric muscle tension. Objective: To identify the effects of dehydration on 5 physiologic characteristics of delayed-onset muscle soreness (DOMS) in normothermic men after an eccentric exercise perturbation. Design: Randomized group test-retest design. Setting: Laboratory. Patients or Other Participants: Ten healthy male volunteers randomly assigned to either a euhydration (age = 26.2 ± 4.9 years, height = 174.1 ± 6.0 cm, mass = 86.5 ± 15.3 kg) or dehydration (age = 25.8 ± 2.2 years, height = 177.2 ± 3.1 cm, mass = 84.4 ± 3.8 kg) group. Intervention(s): Subjects performed treadmill walking for 45 minutes in either a thermoneutral (euhydration) or a hot, humid (dehydration) environment. After a rest period to allow for return to the normothermic condition, DOMS was induced with a 45-minute downhill run. Main Outcome Measures: We assessed 5 physiologic characteristics of DOMS before and at intervals after the eccentric exercise. The characteristics were perceived pain of the bilateral quadriceps and overall body, bilateral punctate tenderness of the superficial quadriceps muscles, bilateral knee-flexion passive range of motion, bilateral thigh circumference, and bilateral isometric quadriceps muscle strength. Thermoregulatory and cardiovascular measures were obtained to monitor participants' heat load during exercise. Results: The experimental protocol produced a 0.9% increase in body mass of the euhydration group and a significant 2.7% decrease in body mass of the dehydration group. The downhill-running exercise perturbation induced DOMS in both the euhydrated and dehydrated participants, based on increased bilateral quadriceps and overall body perceived pain and punctate tenderness of the bilateral vastus medialis

  14. TRPV1 and TRPV4 Play Pivotal Roles in Delayed Onset Muscle Soreness

    PubMed Central

    Ota, Hiroki; Katanosaka, Kimiaki; Murase, Shiori; Kashio, Makiko; Tominaga, Makoto; Mizumura, Kazue

    2013-01-01

    Unaccustomed strenuous exercise that includes lengthening contraction (LC) often causes tenderness and movement related pain after some delay (delayed-onset muscle soreness, DOMS). We previously demonstrated that nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) are up-regulated in exercised muscle through up-regulation of cyclooxygenase (COX)-2, and they sensitized nociceptors resulting in mechanical hyperalgesia. There is also a study showing that transient receptor potential (TRP) ion channels are involved in DOMS. Here we examined whether and how TRPV1 and/or TRPV4 are involved in DOMS. We firstly evaluated a method to measure the mechanical withdrawal threshold of the deep tissues in wild-type (WT) mice with a modified Randall-Selitto apparatus. WT, TRPV1−/− and TRPV4−/− mice were then subjected to LC. Another group of mice received injection of murine NGF-2.5S or GDNF to the lateral gastrocnemius (LGC) muscle. Before and after these treatments the mechanical withdrawal threshold of LGC was evaluated. The change in expression of NGF, GDNF and COX-2 mRNA in the muscle was examined using real-time RT-PCR. In WT mice, mechanical hyperalgesia was observed 6–24 h after LC and 1–24 h after NGF and GDNF injection. LC induced mechanical hyperalgesia neither in TRPV1−/− nor in TRPV4−/− mice. NGF injection induced mechanical hyperalgesia in WT and TRPV4−/− mice but not in TRPV1−/− mice. GDNF injection induced mechanical hyperalgesia in WT but neither in TRPV1−/− nor in TRPV4−/− mice. Expression of NGF and COX-2 mRNA was significantly increased 3 h after LC in all genotypes. However, GDNF mRNA did not increase in TRPV4−/− mice. These results suggest that TRPV1 contributes to DOMS downstream (possibly at nociceptors) of NGF and GDNF, while TRPV4 is located downstream of GDNF and possibly also in the process of GDNF up-regulation. PMID:23799042

  15. Dehydration and Symptoms of Delayed-Onset Muscle Soreness in Hyperthermic Males

    PubMed Central

    Cleary, Michelle A; Sweeney, Lori A; Kendrick, Zebulon V; Sitler, Michael R

    2005-01-01

    Context: Exercise in the heat produces cellular conditions that may leave skeletal muscle susceptible to exercise-induced microdamage. Delayed-onset muscle soreness (DOMS) is a clinical model of contraction-induced skeletal muscle injury. Objective: To determine whether thermoregulation during exercise heat stress adversely affects muscle injury and the accompanying DOMS. Design: Randomized group test-retest design. Setting: Laboratory. Patients or Other Participants: Ten healthy male volunteers were randomly assigned to either the euhydration/hyperthermic or dehydration/hyperthermic group. Intervention(s): Participants were randomly assigned to treadmill walking in a hot, humid environmental chamber (40°C and 75% relative humidity) with either oral rehydration (euhydration/hyperthermic) or fluid restriction (dehydration/hyperthermic). Immediately after heat exposure and while hyperthermic, participants performed an eccentrically biased downhill run to induce DOMS. Main Outcome Measure(s): We measured DOMS characteristics pre-exercise and at 0.5, 24, 48, 72, and 96 hours postexercise. Results: Treadmill exercise and exposure to the hot ambient environment elicited a 0.9% body mass loss for the euhydrated/ hyperthermic (mean rectal temperature after 60 minutes of heat-stress trial = 38.2 ± 0.4°C) and 3.3% body mass loss for the dehydrated/hyperthermic participants (mean rectal temperature after 60 minutes of heat-stress trial = 38.1 ± 0.4°C). Quadriceps perceived pain was significantly higher (F5,40 = 18.717, P ≤ .001) than baseline at 24 and 48 hours postexercise, following the classic pattern of DOMS. Overall lower extremity perceived pain was significantly higher for the dehydration/hyperthermia group than the euhydration/hyperthermia group (F1,8 = 6.713, P = .032). Punctate tenderness of the vastus lateralis for the dehydration/hyperthermic group was 6.9% higher (F5,40 = 4.462, P = .003) than for the euhydration/ hyperthermic group. No clinically

  16. Myocellular enzyme leakage, polymorphonuclear neutrophil activation and delayed onset muscle soreness induced by isokinetic eccentric exercise.

    PubMed

    Croisier, J L; Camus, G; Deby-Dupont, G; Bertrand, F; Lhermerout, C; Crielaard, J M; Juchmès-Ferir, A; Deby, C; Albert, A; Lamy, M

    1996-01-01

    To address the question of whether delayed onset muscular soreness (DOMS) following intense eccentric muscle contraction could be due to increased production of the arachidonic acid derived product prostaglandin E2 (PGE2). 10 healthy male subjects were submitted to eccentric and concentric isokinetic exercises on a Kin Trex device at 60 degrees/s angular velocity. Exercise consisted of 8 stages of 5 maximal contractions of the knee extensor and flexor muscle groups of both legs separated by 1 min rest phases. There was an interval of at least 30 days between eccentric and concentric testing, and the order of the two exercise sessions was randomly assigned. The subjective presence and intensity of DOMS was evaluated using a visual analogue scale, immediately, following 24 h and 48 h after each test. Five blood samples were drawn from an antecubital vein: at rest before exercise, immediately after, after 30 min recovery, 24 h and 48 h after the tests. The magnitude of the acute inflammatory response to exercise was assessed by measuring plasma levels of polymorphonuclear elastase ([EL]), myeloperoxidase ([MPO]) and PGE2 ([PGE2]). Using two way analysis of variance, it appeared that only eccentric exercise significantly increased [EL] and DOMS, especially of the hamstring muscles. Furthermore, a significant decrease in eccentric peak torque of this muscle group only was observed on day 2 after eccentric work (- 21%; P < 0.002). Serum activity of creatine kinase and serum concentration of myoglobin increased significantly 24 and 48 h after both exercise tests. However, these variables reached significantly higher values following eccentric contractions 48 h after exercise. Mean [PGE2] in the two exercise modes remained unchanged over time and were practically equal at each time point. On the basis of these findings, we conclude that the magnitude of polymorphonuclear (PMN) activation, muscle damage, and DOMS are greater after eccentric than after concentric muscle

  17. Electron Tomographic Analysis of Somatic Cell Plate Formation in Meristematic Cells of Arabidopsis Preserved by High-Pressure FreezingW⃞

    PubMed Central

    Seguí-Simarro, José M.; Austin, Jotham R.; White, Erin A.; Staehelin, L. Andrew

    2004-01-01

    We have investigated the process of somatic-type cytokinesis in Arabidopsis (Arabidopsis thaliana) meristem cells with a three-dimensional resolution of ∼7 nm by electron tomography of high-pressure frozen/freeze-substituted samples. Our data demonstrate that this process can be divided into four phases: phragmoplast initials, solid phragmoplast, transitional phragmoplast, and ring-shaped phragmoplast. Phragmoplast initials arise from clusters of polar microtubules (MTs) during late anaphase. At their equatorial planes, cell plate assembly sites are formed, consisting of a filamentous ribosome-excluding cell plate assembly matrix (CPAM) and Golgi-derived vesicles. The CPAM, which is found only around growing cell plate regions, is suggested to be responsible for regulating cell plate growth. Virtually all phragmoplast MTs terminate inside the CPAM. This association directs vesicles to the CPAM and thereby to the growing cell plate. Cell plate formation within the CPAM appears to be initiated by the tethering of vesicles by exocyst-like complexes. After vesicle fusion, hourglass-shaped vesicle intermediates are stretched to dumbbells by a mechanism that appears to involve the expansion of dynamin-like springs. This stretching process reduces vesicle volume by ∼50%. At the same time, the lateral expansion of the phragmoplast initials and their CPAMs gives rise to the solid phragmoplast. Later arriving vesicles begin to fuse to the bulbous ends of the dumbbells, giving rise to the tubulo-vesicular membrane network (TVN). During the transitional phragmoplast stage, the CPAM and MTs disassemble and then reform in a peripheral ring phragmoplast configuration. This creates the centrifugally expanding peripheral cell plate growth zone, which leads to cell plate fusion with the cell wall. Simultaneously, the central TVN begins to mature into a tubular network, and ultimately into a planar fenestrated sheet (PFS), through the removal of membrane via clathrin

  18. PHYSICAL PROPERTIES OF DENSE CORES IN THE {rho} OPHIUCHI MAIN CLOUD AND A SIGNIFICANT ROLE OF EXTERNAL PRESSURES IN CLUSTERED STAR FORMATION

    SciTech Connect

    Maruta, Hajime; Nishi, Ryoichi; Nakamura, Fumitaka; Ikeda, Norio; Kitamura, Yoshimi

    2010-05-01

    Using the archive data of the H{sup 13}CO{sup +} (J = 1-0) line emission taken with the Nobeyama 45 m radio telescope with a spatial resolution of {approx} 0.01 pc, we have identified 68 dense cores in the central dense region of the {rho} Ophiuchi main cloud. The H{sup 13}CO{sup +} data also indicate that the fractional abundance of H{sup 13}CO{sup +} relative to H{sub 2} is roughly inversely proportional to the square root of the H{sub 2} column density with a mean of 1.72 x 10{sup -11}. The mean radius, FWHM line width, and LTE mass of the identified cores are estimated to be 0.045 {+-} 0.011 pc, 0.49 {+-} 0.14 km s{sup -1}, and 3.4 {+-} 3.6 M{sub sun}, respectively. The majority of the identified cores have subsonic internal motions. The virial ratio, the ratio of the virial mass to the LTE mass, tends to decrease with increasing LTE mass and about 60% of the cores have virial ratios smaller than 2, indicating that these cores are not transient structures but self-gravitating. The detailed virial analysis suggests that the surface pressure often dominates over the self-gravity and thus plays a crucial role in regulating core formation and evolution. By comparing the {rho} Oph cores with those in the Orion A molecular cloud observed with the same telescope, we found that the statistical properties of the core physical quantities are similar between the two clouds if the effect of the different spatial resolutions is corrected. The line widths of the {rho} Oph cores appear to be nearly independent of the core radii over the range of 0.01-0.1 pc and deviate upward from the Heyer and Brunt relation. This may be evidence that turbulent motions are driven by protostellar outflows in the cluster environment.

  19. Evaluation of siderite and magnetite formation in BIFs by pressure-temperature experiments of Fe(III) minerals and microbial biomass

    NASA Astrophysics Data System (ADS)

    Halama, Maximilian; Swanner, Elizabeth D.; Konhauser, Kurt O.; Kappler, Andreas

    2016-09-01

    Anoxygenic phototrophic Fe(II)-oxidizing bacteria potentially contributed to the deposition of Archean banded iron formations (BIFs), before the evolution of cyanobacterially-generated molecular oxygen (O2), by using sunlight to oxidize aqueous Fe(II) and precipitate Fe(III) (oxyhydr)oxides. Once deposited at the seafloor, diagenetic reduction of the Fe(III) (oxyhydr)oxides by heterotrophic bacteria produced secondary Fe(II)-bearing minerals, such as siderite (FeCO3) and magnetite (Fe3O4), via the oxidation of microbial organic carbon (i.e., cellular biomass). During deeper burial at temperatures above the threshold for life, thermochemical Fe(III) reduction has the potential to form BIF-like minerals. However, the role of thermochemical Fe(III) reduction of primary BIF minerals during metamorphism, and its impact on mineralogy and geochemical signatures in BIFs, is poorly understood. Consequently, we simulated the metamorphism of the precursor and diagenetic iron-rich minerals (ferrihydrite, goethite, hematite) at low-grade metamorphic conditions (170 °C, 1.2 kbar) for 14 days by using (1) mixtures of abiotically synthesized Fe(III) minerals and either microbial biomass or glucose as a proxy for biomass, and (2) using biogenic minerals formed by phototrophic Fe(II)-oxidizing bacteria. Mössbauer spectroscopy and μXRD showed that thermochemical magnetite formation was limited to samples containing ferrihydrite and glucose, or goethite and glucose. No magnetite was formed from Fe(III) minerals when microbial biomass was present as the carbon and electron sources for thermochemical Fe(III) reduction. This could be due to biomass-derived organic molecules binding to the mineral surfaces and preventing solid-state conversion to magnetite. Mössbauer spectroscopy revealed siderite contents of up to 17% after only 14 days of incubation at elevated temperature and pressure for all samples with synthetic Fe(III) minerals and biomass, whereas 6% of the initial Fe(III) was

  20. Nanosize-induced drastic drop in equilibrium hydrogen pressure for hydride formation and structural stabilization in Pd-Rh solid-solution alloys.

    PubMed

    Kobayashi, Hirokazu; Morita, Hitoshi; Yamauchi, Miho; Ikeda, Ryuichi; Kitagawa, Hiroshi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki; Toh, Shoichi; Matsumura, Syo

    2012-08-01

    We have synthesized and characterized homogeneous solid-solution alloy nanoparticles of Pd and Rh, which are immiscible with each other in the equilibrium bulk state at around room temperature. The Pd-Rh alloy nanoparticles can absorb hydrogen at ambient pressure and the hydrogen pressure of Pd-Rh alloys for hydrogen storage is dramatically decreased by more than 4 orders of magnitude from the corresponding pressure in the metastable bulk state. The solid-solution state is still maintained in the nanoparticles even after hydrogen absorption/desorption, in contrast to the metastable bulks which are separated into Pd and Rh during the process.

  1. Wellbore pressure transducer

    DOEpatents

    Shuck, Lowell Z.

    1979-01-01

    Subterranean earth formations containing energy values are subjected to hydraulic fracturing procedures to enhance the recovery of the energy values. These fractures are induced in the earth formation by pumping liquid into the wellbore penetrating the earth formation until the pressure of the liquid is sufficient to fracture the earth formation adjacent to the wellbore. The present invention is directed to a transducer which is positionable within the wellbore to generate a signal indicative of the fracture initiation useful for providing a timing signal to equipment for seismic mapping of the fracture as it occurs and for providing a measurement of the pressure at which the fracture is initiated.

  2. Influence of the reactive atmosphere on the formation of nanoparticles in the plasma plume induced by nanosecond pulsed laser irradiation of metallic targets at atmospheric pressure and high repetition rate

    NASA Astrophysics Data System (ADS)

    Girault, M.; Le Garrec, J.-L.; Mitchell, J. B. A.; Jouvard, J.-M.; Carvou, E.; Menneveux, J.; Yu, J.; Ouf, F.-X.; Carles, S.; Potin, V.; Pillon, G.; Bourgeois, S.; Perez, J.; Marco de Lucas, M. C.; Lavisse, L.

    2016-06-01

    The influence of a reactive atmosphere on the formation of nanoparticles (NPs) in the plasma plume generated by nanosecond pulsed laser irradiation of metal targets (Ti, Al, Ag) was probed in situ using Small Angle X-ray Scattering (SAXS). Air and different O2-N2 gas mixtures were used as reactive gas within atmospheric pressure. SAXS results showed the formation of NPs in the plasma-plume with a mean radius varying in the 2-5 nm range. A decrease of the NPs size with increasing the O2 percentage in the O2-N2 gas mixture was also showed. Ex situ observations by transmission electron microscopy and structural characterizations by X-ray diffraction and Raman spectroscopy were also performed for powders collected in experiments done using air as ambient gas. The stability of the different metal oxides is discussed as being a key parameter influencing the formation of NPs in the plasma-plume.

  3. Pressure-Induced Amorphization of Small Pore Zeolites—the Role of Cation-H2O Topology and Anti-glass Formation

    PubMed Central

    Chan Hwang, Gil; Joo Shin, Tae; Blom, Douglas A.; Vogt, Thomas; Lee, Yongjae

    2015-01-01

    Systematic studies of pressure-induced amorphization of natrolites (PIA) containing monovalent extra-framework cations (EFC) Li+, Na+, K+, Rb+, Cs+ allow us to assess the role of two different EFC-H2O configurations within the pores of a zeolite: one arrangement has H2O molecules (NATI) and the other the EFC (NATII) in closer proximity to the aluminosilicate framework. We show that NATI materials have a lower onset pressure of PIA than the NATII materials containing Rb and Cs as EFC. The onset pressure of amorphization (PA) of NATII materials increases linearly with the size of the EFC, whereas their initial bulk moduli (P1 phase) decrease linearly. Only Cs- and Rb-NAT reveal a phase separation into a dense form (P2 phase) under pressure. High-Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM) imaging shows that after recovery from pressures near 25 and 20 GPa long-range ordered Rb-Rb and Cs-Cs correlations continue to be present over length scales up to 100 nm while short-range ordering of the aluminosilicate framework is significantly reduced—this opens a new way to form anti-glass structures. PMID:26455345

  4. Method of fracturing a geological formation

    DOEpatents

    Johnson, James O.

    1990-01-01

    An improved method of fracturing a geological formation surrounding a well bore is disclosed. A relatively small explosive charge is emplaced in a well bore and the bore is subsequently hydraulically pressurized to a pressure less than the formation breakdown pressure and preferably greater than the fracture propagation pressure of the formation. The charge is denoted while the bore is so pressurized, resulting in the formation of multiple fractures in the surrounding formation with little or no accompanying formation damage. Subsequent hydraulic pressurization can be used to propagate and extend the fractures in a conventional manner. The method is useful for stimulating production of oil, gas and possibly water from suitable geologic formations.

  5. Submarine rescue decompression procedure from hyperbaric exposures up to 6 bar of absolute pressure in man: effects on bubble formation and pulmonary function.

    PubMed

    Blatteau, Jean-Eric; Hugon, Julien; Castagna, Olivier; Meckler, Cédric; Vallée, Nicolas; Jammes, Yves; Hugon, Michel; Risberg, Jan; Pény, Christophe

    2013-01-01

    Recent advances in submarine rescue systems have allowed a transfer under pressure of crew members being rescued from a disabled submarine. The choice of a safe decompression procedure for pressurised rescuees has been previously discussed, but no schedule has been validated when the internal submarine pressure is significantly increased i.e. exceeding 2.8 bar absolute pressure. This study tested a saturation decompression procedure from hyperbaric exposures up to 6 bar, the maximum operating pressure of the NATO submarine rescue system. The objective was to investigate the incidence of decompression sickness (DCS) and clinical and spirometric indices of pulmonary oxygen toxicity. Two groups were exposed to a Nitrogen-Oxygen atmosphere (pO2 = 0.5 bar) at either 5 bar (N = 14) or 6 bar (N = 12) for 12 h followed by 56 h 40 min resp. 60 h of decompression. When chamber pressure reached 2.5 bar, the subjects breathed oxygen intermittently, otherwise compressed air. Repeated clinical examinations, ultrasound monitoring of venous gas embolism and spirometry were performed during decompression. During exposures to 5 bar, 3 subjects had minor subjective symptoms i.e. sensation of joint discomfort, regressing spontaneously, and after surfacing 2 subjects also experienced joint discomfort disappearing without treatment. Only 3 subjects had detectable intravascular bubbles during decompression (low grades). No bubbles were detected after surfacing. About 40% of subjects felt chest tightness when inspiring deeply during the initial phase of decompression. Precordial burning sensations were reported during oxygen periods. During decompression, vital capacity decreased by about 8% and forced expiratory flow rates decreased significantly. After surfacing, changes in the peripheral airways were still noticed; Lung Diffusion for carbon monoxide was slightly reduced by 1% while vital capacity was normalized. The procedure did not result in serious symptoms of DCS or

  6. Initial diagnosis of anemia from sore mouth and improved classification of anemias by MCV and RDW in 30 patients.

    PubMed

    Lu, Shin-Yu; Wu, Hong-Cheng

    2004-12-01

    Thirty patients with a wide range of sore mouth that led to the diagnosis of iron deficiency in 12 patients, pernicious anemia in 8 patients, combined deficiency of iron and vitamin B12 in 2 patients, and anemia of chronic disease in 8 patients were investigated. The oral signs and symptoms included glossitis, glossodynia, angular cheilitis, recurrent oral ulcer, oral candidosis, diffuse erythematous mucositis, and pale oral mucosa. The values of hemoglobin in 30 patients varied from normal to severe life-threatening levels, but none had developed generalized symptoms sufficiently advanced to arouse suspicions of anemia before they visited the Oral Medicine Clinic. The aim of this paper is to describe a retrospective study of 30 patients with oral changes as the initial manifestation of nutritional deficiency or anemia of chronic diseases. Improved diagnosis and classification of anemia based on the mean and heterogeneity of red cell size will be discussed.

  7. Tolerability of ibuprofen, aspirin and paracetamol for the treatment of cold and flu symptoms and sore throat pain.

    PubMed

    Moore, N; Le Parc, J M; van Ganse, E; Wall, R; Schneid, H; Cairns, R

    2002-12-01

    This double-blind randomised study compared the tolerability of ibuprofen (up to 1.2 g daily), aspirin and paracetamol (both up to 3 g daily) for up to seven days, in patients with mild to moderate pain resulting from cold/flu symptoms or sore throat (CF/ST) (n = 2,815). The main outcome was the rate of significant adverse events (SGAE). Rates of SGAE for ibuprofen, aspirin and paracetamol were respectively 12.0%, 15.7% and 12.3%. Ibuprofen was significantly better tolerated than aspirin (p = 0.02) and had comparable tolerability with paracetamol. The latter was also true for total digestive system events and for abdominal pain and dyspepsia. In conclusion, in patients with CF/ST, ibuprofen used at over-the-counter doses is as well tolerated as paracetamol and much better tolerated than aspirin.

  8. Ultrafine aerosol size distributions and sulfuric acid vapor pressures: Implications for new particle formation in the atmosphere. Year 2 progress report

    SciTech Connect

    McMurry, P.H.

    1993-07-01

    This project has two components: (1) measurement of H{sub 2}SO{sub 4} vapor pressures in air under temperature/relative humidity conditions similar to atmospheric, and (2) measurement of ultrafine aerosol size distributions. During Year 2, more effort was put on size distribution measurements. 4 figs.

  9. Revealing the Formation Mechanism and Effect of Pressure on the Magnetic Order of Multiferroic BiMn2O5 Through Neutron Powder Diffraction

    NASA Astrophysics Data System (ADS)

    Dang, N. T.; Kozlenko, D. P.; Kichanov, S. E.; Jabarov, S. G.; Mammadov, A. I.; Mekhtieva, R. Z.; Phan, T. L.; Smotrakov, V. G.; Eremkin, V. V.; Savenko, B. N.

    2017-02-01

    The crystal and magnetic structures of the strong magnetoelectric BiMn2O5 have been studied as a function of pressure up to 5.7 GPa in the temperature range from 10 K to 60 K by means of neutron powder diffraction. The results reveal that the Pbam orthorhombic crystal structure remains unchanged in the investigated thermodynamic range. At ambient pressure, a long-range commensurate antiferromagnetic (AFM) phase with propagation vector q = (1/2, 0, 1/2) formed below T N = 41(2) K, accompanied by anomalies in the temperature dependence of structural parameters including the lattice parameters, interatomic distances, and bond angles. This AFM phase remained stable in the studied pressure range, and the relevant pressure coefficient of the Néel temperature was determined to be 3.0(4) K/GPa. No incommensurate AFM phase was detected. The magnetic properties of BiMn2O5 and their difference from most other RMn2O5 compounds were analyzed in terms of competing exchange interactions.

  10. The Effects of Proprioceptive Neuromuscular Facilitation Stretching on Post-Exercise Delayed Onset Muscle Soreness in Young Adults.

    PubMed

    McGRATH, Ryan P; Whitehead, James R; Caine, Dennis J

    Until recently, the scientific community believed that post-exercise stretching could reduce delayed onset muscle soreness (DOMS), but recent reviews of studies on the topic have concluded that pre- or post-exercise static stretching has no effect on mitigating DOMS. However, the effect of proprioceptive neuromuscular facilitation (PNF) post-exercise stretching on preventing DOMS has not been adequately studied. The purpose of this study was to determine the effect of post-exercise PNF stretching on DOMS. Young adult participants (N=57) were randomly assigned to a PNF stretching group (n=19), a static stretching group (n=20), and to a no-stretching control group (n=18). All participants completed exercise designed to induce DOMS prior to post-exercise experimental stretching protocols. Participants rated their soreness level on a pain scale 24 and 48 hours post-exercise. A 3 × 2 mixed ANOVA showed there was an effect for time (p<.01). Post hoc testing revealed that DOMS pain significantly decreased (p<.05) from 24 to 48 hours post-exercise for the PNF and control groups, but not for the static stretching group. Other analyses revealed a significant correlation (r=.61, p<.01) between the pre- and post-exercise stretch scores and the 48 hour post-exercise pain score for the PNF group. Consistent with the results of previous research on post-exercise static stretching, these results indicate that post-exercise PNF stretching also does not prevent DOMS. However, the correlation analysis suggests it is possible the pre-stretch muscle contractions of the post-exercise PNF protocol may have placed a load on an already damaged muscle causing more DOMS for some participants.

  11. The Effects of Proprioceptive Neuromuscular Facilitation Stretching on Post-Exercise Delayed Onset Muscle Soreness in Young Adults

    PubMed Central

    McGRATH, RYAN P.; WHITEHEAD, JAMES R.; CAINE, DENNIS J.

    2014-01-01

    Until recently, the scientific community believed that post-exercise stretching could reduce delayed onset muscle soreness (DOMS), but recent reviews of studies on the topic have concluded that pre- or post-exercise static stretching has no effect on mitigating DOMS. However, the effect of proprioceptive neuromuscular facilitation (PNF) post-exercise stretching on preventing DOMS has not been adequately studied. The purpose of this study was to determine the effect of post-exercise PNF stretching on DOMS. Young adult participants (N=57) were randomly assigned to a PNF stretching group (n=19), a static stretching group (n=20), and to a no-stretching control group (n=18). All participants completed exercise designed to induce DOMS prior to post-exercise experimental stretching protocols. Participants rated their soreness level on a pain scale 24 and 48 hours post-exercise. A 3 × 2 mixed ANOVA showed there was an effect for time (p<.01). Post hoc testing revealed that DOMS pain significantly decreased (p<.05) from 24 to 48 hours post-exercise for the PNF and control groups, but not for the static stretching group. Other analyses revealed a significant correlation (r=.61, p<.01) between the pre- and post-exercise stretch scores and the 48 hour post-exercise pain score for the PNF group. Consistent with the results of previous research on post-exercise static stretching, these results indicate that post-exercise PNF stretching also does not prevent DOMS. However, the correlation analysis suggests it is possible the pre-stretch muscle contractions of the post-exercise PNF protocol may have placed a load on an already damaged muscle causing more DOMS for some participants. PMID:27182398

  12. Boundary pressure of inter-connection of Fe-Ni-S melt in olivine based on in-situ X-ray tomography: Implication to core formation in asteroids

    NASA Astrophysics Data System (ADS)

    Terasaki, H.; Urakawa, S.; Uesugi, K.; Nakatsuka, A.; Funakoshi, K.; Ohtani, E.

    2011-12-01

    Interconnectivity of Fe-alloy melt in crystalline silicates is important property for the core formation mechanism in planetary interior. In previous studies, the interconnectivity of Fe-alloy melt has been studied based on textural observation of recovered samples from high pressure and temperature. However, there is no observation under high pressure and temperature. We have developed 80-ton uni-axial press for X-ray computed micro-tomography (X-CT) and performed X-CT measurement under high pressure (Urakawa et al. 2010). Here we report X-CT measurement of Fe-Ni-S melt in crystalline olivine and interconnectivity of the melt up to 3.5 GPa and 1273 K. X-CT measurements were carried out at BL20B2 beamline, SPring-8 synchrotron facility. The sample was powder mixture of Fe-Ni-S and olivine, which was enclosed in graphite capsule. Heating was performed using a cylindrical graphite furnace. Pressure was generated using opposed toroidal-shape WC anvil. The uni-axial press was set on the rotational stage and X-ray radiography image of the sample was collected using CCD camera from 0°to 180°with 0.3° step. 3-D image of the sample was obtained by reconstructing the 2-D radiography image. The 3-D CT image shows that the size of the Fe-Ni-S melt increased significantly compared to that before melting below 2.5 GPa, suggesting that the melt was interconnected in olivine crystals. On the other hand, 3-D texture of the sample at 3.5 GPa did not show difference from that before melting. Therefore, the boundary of inter-connection of Fe-Ni-S melt is likely to locate between 2.5 and 3.5 GPa. This result is important application for the core formation mechanism especially in small bodies, such as differentiated asteroids.

  13. Influence of the oxygen concentration on the formation of crystalline phases of TiO2 during the low-pressure arc-discharge plasma synthesis

    NASA Astrophysics Data System (ADS)

    Ushakov, A. V.; Karpov, I. V.; Lepeshev, A. A.

    2016-02-01

    The synthesis of titanium dioxide (TiO2) nanoparticles with different percentage of anatase and rutile phases is investigated. The synthesis is performed by controlling the oxygen percentage in the gas mixture in the plasmachemical evaporation-condensation process employing a low-pressure arc discharge. In all our experiments, the pressure in the plasmachemical reactor and the average size of particles remain constant and are 60 Pa and 6 nm, respectively. The crystal structure of synthesized TiO2 is studied using X-ray diffraction; the morphology of the particles is analyzed employing transmission electron microscopy. Using X-ray phase analysis, it is established that the concentration of the TiO2 anatase phase decreases upon a decrease in the oxygen concentration in the gas mixture. It is shown that the TiO2 anatase phase is more efficient for photocatalytic decomposition of methylene blue than the rutile phase.

  14. Effect of pressure on the formation of superelastic hard particles in a metal-fullerene system and the tribological properties of composite materials reinforced with such particles

    NASA Astrophysics Data System (ADS)

    Chernogorova, O. P.; Drozdova, E. I.; Blinov, V. M.; Ovchinnikova, I. N.

    2011-03-01

    Raman spectroscopy, X-ray diffraction, and microhardness and modulus of elasticity measurements are used to study the influence of compacting pressure (5, 8 GPa) on the structure and properties of the phases prepared from fullerene soot extract (mixture of C60 and C70 crystallites) in a mixture with a cobalt powder. Carbon particles synthesized during high-temperature treatment at a pressure of 5 or 8 GPa and reinforcing composite samples have a universal hardness H u (hardness measured from the total (elastic and plastic) strain under loading) of 12 or 25 GPa, respectively. After heating of samples to 900°C, the values of H u of the particles decrease to 9-11 GPa at elastic recovery of the phase more than 85%. The dry friction coefficients of iron- and cobalt-based composite materials in contact with tool steel are 0.08 and 0.04, respectively.

  15. In situ TEM observation of the Boudouard reaction: multi-layered graphene formation from CO on cobalt nanoparticles at atmospheric pressure.

    PubMed

    Bremmer, G Marien; Zacharaki, Eirini; Sjåstad, Anja O; Navarro, Violeta; Frenken, Joost W M; Kooyman, Patricia J

    2017-02-09

    Using a MEMS nanoreactor in combination with a specially designed in situ Transmission Electron Microscope (TEM) holder and gas supply system, we imaged the formation of multiple layers of graphene encapsulating a cobalt nanoparticle, at 1 bar CO : N2 (1 : 1) and 500 °C. The cobalt nanoparticle was imaged live in a TEM during the Boudouard reaction. The in situ/operando TEM studies give insight into the behaviour of the catalyst at the nanometer-scale, under industrially relevant conditions. When switching from Fischer-Tropsch syngas conditions (CO : H2 : N2 1 : 2 : 3 at 1 bar) to CO-rich conditions (CO : N2 1 : 1 at 1 bar), we observed the formation of multi-layered graphene on Co nanoparticles at 500 °C. Due to the high temperature, the surface of the Co nanoparticles facilitated the Boudouard reaction, causing CO dissociation and the formation of layers of graphene. After the formation of the first patches of graphene at the surface of the nanoparticle, more and more layers grew over the course of about 40 minutes. In its final state, around 10 layers of carbon capped the nanoparticle. During this process, the carbon shell caused mechanical stress in the nanoparticle, inducing permanent deformation.

  16. Pressure ulcers: Back to the basics

    PubMed Central

    Agrawal, Karoon; Chauhan, Neha

    2012-01-01

    Pressure ulcer in an otherwise sick patient is a matter of concern for the care givers as well as the medical personnel. A lot has been done to understand the disease process. So much so that USA and European countries have established advisory panels in their respective continents. Since the establishment of these organizations, the understanding of the pressure ulcer has improved significantly. The authors feel that the well documented and well publicized definition of pressure ulcer is somewhat lacking in the correct description of the disease process. Hence, a modified definition has been presented. This disease is here to stay. In the process of managing these ulcers the basic pathology needs to be understood well. Pressure ischemia is the main reason behind the occurrence of ulceration. Different extrinsic and intrinsic factors have been described in detail with review of literature. There are a large number of risk factors causing ulceration. The risk assessment scales have eluded the surgical literature and mostly remained in nursing books and websites. These scales have been reproduced for completion of the basics on decubitus ulcer. The classification of the pressure sores has been given in a comparative form to elucidate that most of the classifications are the same except for minor variations. The management of these ulcers is ever evolving but the age old saying of “prevention is better than cure” suits this condition the most. PMID:23162223

  17. Effect of solvent, temperature and pressure on the stability of chiral and perovskite metal formate frameworks of [NH2NH3][M(HCOO)3] (M = Mn, Fe, Zn).

    PubMed

    Mączka, Mirosław; Pasińska, Katarzyna; Ptak, Maciej; Paraguassu, Waldeci; da Silva, Tercio Almeida; Sieradzki, Adam; Pikul, Adam

    2016-11-23

    We report the synthesis, crystal structure, and thermal, Raman, infrared and magnetic properties of [NH2NH3][M(HCOO)3] (HyM) compounds (M = Mn, Zn, Fe). Our results show that synthesis from methanol solution leads to perovskite polymorphs while that from 1-methyl-2-pyrrolidinone or its mixture with methanol allows obtaining chiral polymorphs. Perovskite HyFe, chiral HyFe and chiral HyMn undergo phase transitions at 347, 336 and 296 K, respectively, with symmetry changes from Pnma to Pna21, P63 to P212121 and P63 to P21. X-ray diffraction and Raman studies show that the phase transitions are governed by dynamics of the hydrazinium ions. Low-temperature magnetic studies show that these compounds exhibit magnetic ordering below 9-12.5 K. Since the low-temperature structures of chiral HyMn and perovskite HyFe are polar, these compounds are possible multiferroic materials. We also report high-pressure Raman scattering studies of chiral and perovskite HyZn, which show much larger stiffness of the latter phase. These studies also show that the ambient pressure polar phases are stable up to at least 1.4 and 4.1 GPa for the chiral and perovskite phase, respectively. Between 1.4 and 2.0 GPa (for chiral HyZn) and 4.1 and 5.2 GPa (for perovskite HyZn) pressure-induced transitions are observed associated with changes in the zinc-formate framework. Strong broadening of Raman bands and the decrease in their number for the high-pressure phase of chiral HyZn suggest that this phase is disordered and has higher symmetry than the ambient pressure one.

  18. The Evidence-Based Principles of Negative Pressure Wound Therapy in Trauma & Orthopedics

    PubMed Central

    A, Novak; Khan, Wasim S; J, Palmer

    2014-01-01

    Negative pressure wound therapy is a popular treatment for the management of both acute and chronic wounds. Its use in trauma and orthopedics is diverse and includes the acute traumatic setting as well as chronic troublesome wounds associated with pressure sores and diabetic foot surgery. Efforts have been made to provide an evidence base to guide its use however this has been limited by a lack of good quality evidence. The following review article explores the available evidence and describes future developments for its use in trauma and orthopaedic practice. PMID:25067971

  19. Abundant molecular gas and inefficient star formation in intracluster regions: ram pressure stripped tail of the Norma galaxy ESO137-001

    SciTech Connect

    Jáchym, Pavel; Combes, Françoise; Cortese, Luca; Sun, Ming; Kenney, Jeffrey D. P.

    2014-09-01

    For the first time, we reveal large amounts of cold molecular gas in a ram-pressure-stripped tail, out to a large 'intracluster' distance from the galaxy. With the Actama Pathfinder EXperiment (APEX) telescope, we have detected {sup 12}CO(2-1) emission corresponding to more than 10{sup 9} M {sub ☉} of H{sub 2} in three Hα bright regions along the tail of the Norma cluster galaxy ESO 137-001, out to a projected distance of 40 kpc from the disk. ESO 137-001 has an 80 kpc long and bright X-ray tail associated with a shorter (40 kpc) and broader tail of numerous star forming H II regions. The amount of ∼1.5 × 10{sup 8} M {sub ☉} of H{sub 2} found in the most distant region is similar to molecular masses of tidal dwarf galaxies, though the standard Galactic CO-to-H{sub 2} factor could overestimate the H{sub 2} content. Along the tail, we find the amount of molecular gas to drop, while masses of the X-ray-emitting and diffuse ionized components stay roughly constant. Moreover, the amounts of hot and cold gas are large and similar, and together nearly account for the missing gas from the disk. We find a very low SFE (τ{sub dep} > 10{sup 10} yr) in the stripped gas in ESO 137-001 and suggest that this is due to a low average gas density in the tail, or turbulent heating of the interstellar medium that is induced by a ram pressure shock. The unprecedented bulk of observed H{sub 2} in the ESO 137-001 tail suggests that some stripped gas may survive ram pressure stripping in the molecular phase.

  20. Feasibility of observing small differences in friction mean effective pressure between different lubricating oil formations using small, single-cylinder motored engine rig

    DOE PAGES

    Rohr, William F.; Nguyen, Ke; Bunting, Bruce G.; ...

    2015-09-01

    Here, the feasibility of using a motored single-cylinder 517 cc diesel engine to observe small frictional differences between oil formulations is investigated. Friction mean effective pressure (FMEP) is measured and compared for an SAE 10W-30 and an SAE 5W-20 oil in three stages of production: base oil, commercial oil without a friction and wear reducing additive, and fully formulated commercial oil. In addition, a commercial SAE 5W-30 engine oil is investigated. Friction mean effective pressure is plotted versus oil dynamic viscosity to compare the lubricant FMEP at a given viscosity. Linear regressions and average friction mean effective pressure are usedmore » as a secondary means of comparing FMEP for the various oil formulations. Differences between the oils are observed with the base oil having higher friction at a given viscosity but a lower average FMEP due to the temperature distribution of the test and lower viscosities reached by the base oil. The commercial oil is shown to have both a higher FMEP at a given viscosity and a higher average FMEP than the commercial oil without a friction and wear reducing additive. The increase in friction for the oil without a friction and wear reduction additive indicates that the operational regime of the engine may be out of the bounds of the optimal regime for the additive or that the additive is more optimized for wear reduction. Results show that it is feasible to observe small differences in FMEP between lubricating oil formulations using a small, single-cylinder motored engine.« less