201 results on '"Strauss, J."'
Search Results
2. GLUT4 localisation with the plasma membrane is unaffected by an increase in plasma free fatty acid availability.
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Barrett, J. S., Strauss, J. A., Chow, L. S., Shepherd, S. O., Wagenmakers, A. J. M., and Wang, Y.
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CELL membranes ,FREE fatty acids ,SKELETAL muscle - Abstract
Background: Insulin-stimulated glucose uptake into skeletal muscle occurs via translocation of GLUT4 from intracellular storage vesicles to the plasma membrane. Elevated free fatty acid (FFA) availability via a lipid infusion reduces glucose disposal, but this occurs in the absence of impaired proximal insulin signalling. Whether GLUT4 localisation to the plasma membrane is subsequently affected by elevated FFA availability is not known. Methods: Trained (n = 11) and sedentary (n = 10) individuals, matched for age, sex and body mass index, received either a 6 h lipid or glycerol infusion in the setting of a concurrent hyperinsulinaemic-euglycaemic clamp. Sequential muscle biopsies (0, 2 and 6 h) were analysed for GLUT4 membrane localisation and microvesicle size and distribution using immunofluorescence microscopy. Results: At baseline, trained individuals had more small GLUT4 spots at the plasma membrane, whereas sedentary individuals had larger GLUT4 spots. GLUT4 localisation with the plasma membrane increased at 2 h (P = 0.04) of the hyperinsulinemic-euglycemic clamp, and remained elevated until 6 h, with no differences between groups or infusion type. The number of GLUT4 spots was unchanged at 2 h of infusion. However, from 2 to 6 h there was a decrease in the number of small GLUT4 spots at the plasma membrane (P = 0.047), with no differences between groups or infusion type. Conclusion: GLUT4 localisation with the plasma membrane increases during a hyperinsulinemic-euglycemic clamp, but this is not altered by elevated FFA availability. GLUT4 appears to disperse from small GLUT4 clusters located at the plasma membrane to support glucose uptake during a hyperinsulinaemic-euglycaemic clamp. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. 590 Roles of translesion DNA polymerases in poledependent mutagenesis.
- Author
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Strauss, J, Kay, A, Vassalotti, A, Ellis, A, Haddad, S, and Pursell, Z
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- 2025
- Full Text
- View/download PDF
4. Subsea permafrost organic carbon stocks are large and of dominantly low reactivity.
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Miesner, F., Overduin, P. P., Grosse, G., Strauss, J., Langer, M., Westermann, S., Schneider von Deimling, T., Brovkin, V., and Arndt, S.
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CARBON cycle ,PERMAFROST ,ORGANIC compounds ,CARBON - Abstract
Subsea permafrost carbon pools below the Arctic shelf seas are a major unknown in the global carbon cycle. We combine a numerical model of sedimentation and permafrost evolution with simplified carbon turnover to estimate accumulation and microbial decomposition of organic matter on the pan-Arctic shelf over the past four glacial cycles. We find that Arctic shelf permafrost is a globally important long-term carbon sink storing 2822 (1518–4982) Pg OC, double the amount stored in lowland permafrost. Although currently thawing, prior microbial decomposition and organic matter aging limit decomposition rates to less than 48 Tg OC/yr (25–85) constraining emissions due to thaw and suggesting that the large permafrost shelf carbon pool is largely insensitive to thaw. We identify an urgent need to reduce uncertainty in rates of microbial decomposition of organic matter in cold and saline subaquatic environments. Large emissions of methane more likely derive from older and deeper sources than from organic matter in thawing permafrost. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. Regenerative agriculture v. conservation agriculture: potential effects on soil quality, crop productivity and whole-farm economics in Mediterranean-climate regions.
- Author
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Musto, G. A., Swanepoel, P. A., and Strauss, J. A.
- Abstract
Small-grain farming systems in Mediterranean climatic regions are characterized by poor quality soils, high climate variability, and resulting heavy agrochemical reliance. The adoption of Conservation Agriculture, based on minimum tillage, permanent soil cover, and crop rotations, has improved soil quality, enhanced crop productivity, and help mitigate financial risk. However, emerging issues that threaten sustainability, such as herbicide resistance, inputs costs rising disproportionately to product prices, and increasing climate variability and unpredictability, drive the need for innovation in small-grain Mediterranean-based CA systems. The aim of the review was to evaluate a set of agroecological practices which constitute a Regenerative Agriculture (RA) concept, for their potential to address these challenges from a soil quality, crop productivity and whole-farm economics perspective. Organic soil amendments derived from agro-wastes, offer promising perspectives for supplying appropriate quantities of nutrients to reduce or replace mineral fertilisers and offset their economic and agroecological costs. Although the viability of microbial bioeffectors in small-grain agroecosystems was largely under question, non-microbial bioeffectors and certain combination options represent more efficient and cost-effective uses of this technology. Their widely reported abiotic stress priming functions and crop productivity enhancement under poor growing conditions may improve yield stability and financial resilience in small-grain Mediterranean CA systems. Finally, multi-species cover crops subjected to adaptive multi-paddock (AMP) grazing as a phase within the crop rotation may reduce weed pressure, enhance soil multi-functionality, and resilience against environmental stresses. To validate the potential of these technologies in Mediterranean small-grain systems, more long-term and context-specific research is called for. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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6. Biological lability of terrestrial DOM increases CO2 outgassing across Arctic shelves.
- Author
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Polimene, Luca, Torres, R., Powley, H. R., Bedington, M., Juhls, B., Palmtag, J., Strauss, J., and Mann, P. J.
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DISSOLVED organic matter ,CLIMATE feedbacks ,ARCTIC climate ,OUTGASSING ,TERRITORIAL waters ,SEA ice - Abstract
Arctic shelf seas receive greater quantities of river runoff than any other ocean region and are experiencing increased freshwater loads and associated terrestrial matter inputs since recent decades. Amplified terrestrial permafrost thaw and coastal erosion is exposing previously frozen organic matter, enhancing its mobilization and release to nearshore regions. Changing terrestrial dissolved organic matter (terr-DOM) loads and composition may alter shelf primary productivity and respiration, ultimately affecting net regional CO
2 air–sea fluxes. However, the future evolution of Arctic Ocean climate feedbacks are highly dependent upon the biological degradability of terr-DOM in coastal waters, a factor often omitted in modelling studies. Here, we assess the sensitivity of CO2 air–sea fluxes from East Siberian Arctic Shelf (ESAS) waters to changing terr-DOM supply and degradability using a biogeochemical model explicitly accounting for bacteria dynamics and shifting terr-DOM composition. We find increasing terr-DOM loads and degradability trigger a series of biogeochemical and ecological processes shifting ESAS waters from a net sink to a net source of CO2 , even after accounting for strengthening coastal productivity by additional land-derived nutrients. Our results suggest that future projected inputs of labile terr-DOM from peat and permafrost thaw may strongly increase the CO2 efflux from the Arctic shelf sea, causing currently unquantified positive feedback to climate change. [ABSTRACT FROM AUTHOR]- Published
- 2022
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7. 579 - Translesion synthesis polymerases affect mutagenesis and response to DNA damaging agents in mutant POLE cells.
- Author
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Strauss, J, Kay, A, Vassalotti, A, Ellis, A, Williams, L, and Pursell, Z
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- 2024
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8. A solar resource classification algorithm for global horizontal irradiance time series based on frequency domain analysis.
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Lewis, C., Strauss, J. M., and Rix, A. J.
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FREQUENCY-domain analysis ,CLASSIFICATION algorithms ,TIME series analysis ,ZENITH distance ,ALGORITHMS ,FOURIER transforms - Abstract
A novel daily and 15-min period solar resource classification algorithm, based only on the Fourier transform of global horizontal irradiance (GHI) and calculable parameters, is presented. These methods can identify GHI series that are not attenuated by clouds, whether the clouds may or may not be visible. Additional sky condition classes are also adopted in which the representative conditions of the remaining days or periods are classified. Although the proposed day classification is too conservative to be widely applicable, the 15-min period classification is generally in good agreement with the Perez sky clearness index while providing greater sensitivity to turbid conditions and algorithm flexibility. It is shown, however, that the adoption of the clearness index in the proposed 15-min period method less successfully distinguished between clear and constant overcast conditions under winter continental conditions due to relatively large solar zenith angles. It is also shown that the proposed 15-min period and Reno and Hansen statistical methods are generally in good agreement on the detection of clear conditions under temperate conditions. The classification results of the proposed method are further shown in comparison to high-resolution sky images to elucidate the character of each class and the classification algorithm flexibility. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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9. Neuromuscular fatigue and recovery after strenuous exercise depends on skeletal muscle size and stem cell characteristics.
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Baumert, Philipp, Temple, S., Stanley, J. M., Cocks, M., Strauss, J. A., Shepherd, S. O., Drust, B., Lake, M. J., Stewart, C. E., and Erskine, R. M.
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NEUROMUSCULAR diseases ,EXERCISE ,SKELETAL muscle ,STEM cells ,FIBROBLASTS - Abstract
Hamstring muscle injury is highly prevalent in sports involving repeated maximal sprinting. Although neuromuscular fatigue is thought to be a risk factor, the mechanisms underlying the fatigue response to repeated maximal sprints are unclear. Here, we show that repeated maximal sprints induce neuromuscular fatigue accompanied with a prolonged strength loss in hamstring muscles. The immediate hamstring strength loss was linked to both central and peripheral fatigue, while prolonged strength loss was associated with indicators of muscle damage. The kinematic changes immediately after sprinting likely protected fatigued hamstrings from excess elongation stress, while larger hamstring muscle physiological cross-sectional area and lower myoblast:fibroblast ratio appeared to protect against fatigue/damage and improve muscle recovery within the first 48 h after sprinting. We have therefore identified novel mechanisms that likely regulate the fatigue/damage response and initial recovery following repeated maximal sprinting in humans. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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10. Short-term, but not acute, intake of New Zealand blackcurrant extract improves insulin sensitivity and free-living postprandial glucose excursions in individuals with overweight or obesity.
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Nolan, A., Brett, R., Strauss, J. A., Stewart, C. E., and Shepherd, S. O.
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OBESITY treatment ,THERAPEUTIC use of plant extracts ,FLAVONOIDS ,INGESTION ,BLOOD sugar ,DIETARY supplements ,RANDOMIZED controlled trials ,DESCRIPTIVE statistics ,BLIND experiment ,INSULIN resistance - Abstract
Impaired postprandial glucose handling and low-grade systemic inflammation are risk factors for developing insulin resistance in individuals with overweight or obesity. Acute ingestion of anthocyanins improves postprandial glucose responses to a single carbohydrate-rich meal under strictly controlled conditions. Purpose: Examine whether acute and short-term supplementation with anthocyanin-rich New Zealand blackcurrant (NZBC) extract can improve postprandial glucose responses to mixed-macronutrient meals. Methods: Twenty-five overweight (BMI > 25 kg m
2 ) sedentary individuals participated in one of the following double-blinded, randomised controlled trials: (1) ingestion of 600 mg NZBC extract or placebo prior to consumption of a high-carbohydrate, high-fat liquid meal (n = 12); (2) 8-days supplementation with NZBC extract (600 mg day−1 ) or placebo, with insulin sensitivity and markers of inflammation assessed on day-7, and free-living postprandial glucose (continuous glucose monitoring) assessed on day-8 (n = 13). Results: A single dose of NZBC extract had no effect on 3 h postprandial glucose, insulin or triglyceride responses. However, in response to short-term NZBC extract supplementation insulin sensitivity was improved (+ 22%; P = 0.011), circulating C-reactive protein concentrations decreased (P = 0.008), and free-living postprandial glucose responses to both breakfast and lunch meals were reduced (− 9% and − 8%, respectively; P < 0.05), compared to placebo. Conclusion: These novel results indicate that repeated intake, rather than a single dose of NZBC extract, is required to induce beneficial effects on insulin sensitivity and postprandial glucose handling in individuals with overweight or obesity. Continuous glucose monitoring enabled an effect of NZBC extract to be observed under free-living conditions and highlights the potential of anthocyanin-rich supplements as a viable strategy to reduce insulin resistance. [ABSTRACT FROM AUTHOR]- Published
- 2021
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11. A 7‐day high‐fat, high‐calorie diet induces fibre‐specific increases in intramuscular triglyceride and perilipin protein expression in human skeletal muscle.
- Author
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Whytock, K. L., Parry, S. A., Turner, M. C., Woods, R. M., James, L. J., Ferguson, R. A., Ståhlman, M., Borén, J., Strauss, J. A., Cocks, M., Wagenmakers, A. J. M., Hulston, C. J., and Shepherd, S. O.
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HIGH-calorie diet ,SKELETAL muscle ,PROTEIN expression ,CHOLESTEROL content of food ,EPICATECHIN ,MUSCLE proteins ,VASTUS lateralis ,REDUCING diets ,ORTHOKERATOLOGY - Abstract
Key points: We have recently shown that a high‐fat, high‐calorie (HFHC) diet decreases whole body glucose clearance without impairing skeletal muscle insulin signalling, in healthy lean individuals.These diets are also known to increase skeletal muscle IMTG stores, but the effect on lipid metabolites leading to skeletal muscle insulin resistance has not been investigated.This study measured the effect of 7 days' HFHC diet on (1) skeletal muscle concentration of lipid metabolites, and (2) potential changes in the perilipin (PLIN) content of the lipid droplets storing intramuscular triglyceride (IMTG).The HFHC diet increased PLIN3 protein expression and redistributed PLIN2 to lipid droplet stores in type I fibres.The HFHC diet increased IMTG content in type I fibres, while lipid metabolite concentrations remained the same. The data suggest that the increases in IMTG stores assists in reducing the accumulation of lipid metabolites known to contribute to skeletal muscle insulin resistance. A high‐fat, high‐calorie (HFHC) diet reduces whole body glucose clearance without impairing skeletal muscle insulin signalling in healthy lean individuals. HFHC diets also increase skeletal muscle lipid stores. However, unlike certain lipid metabolites, intramuscular triglyceride (IMTG) stored within lipid droplets (LDs) does not directly contribute to skeletal muscle insulin resistance. Increased expression of perilipin (PLIN) proteins and colocalisation to LDs has been shown to assist in IMTG storage. We aimed to test the hypothesis that 7 days on a HFHC diet increases IMTG content while minimising accumulation of lipid metabolites known to disrupt skeletal muscle insulin signalling in sedentary and obese individuals. We also aimed to identify changes in expression and subcellular distribution of proteins involved in IMTG storage. Muscle biopsies were obtained from the m. vastus lateralis of 13 (11 males, 2 females) healthy lean individuals (age: 23 ± 2.5 years; body mass index: 24.5 ± 2.4 kg m−2), following an overnight fast, before and after consuming a high‐fat (64% energy), high‐calorie (+47% kcal) diet for 7 days. After the HFHC diet, IMTG content increased in type I fibres only (+101%; P < 0.001), whereas there was no change in the concentration of either total diacylglycerol (P = 0.123) or total ceramides (P = 0.150). Of the PLINs investigated, only PLIN3 content increased (+50%; P < 0.01) solely in type I fibres. LDs labelled with PLIN2 increased (+80%; P < 0.01), also in type I fibres only. We propose that these adaptations of LDs support IMTG storage and minimise accumulation of lipid metabolites to protect skeletal muscle insulin signalling following 7 days' HFHC diet. Key points: We have recently shown that a high‐fat, high‐calorie (HFHC) diet decreases whole body glucose clearance without impairing skeletal muscle insulin signalling, in healthy lean individuals.These diets are also known to increase skeletal muscle IMTG stores, but the effect on lipid metabolites leading to skeletal muscle insulin resistance has not been investigated.This study measured the effect of 7 days' HFHC diet on (1) skeletal muscle concentration of lipid metabolites, and (2) potential changes in the perilipin (PLIN) content of the lipid droplets storing intramuscular triglyceride (IMTG).The HFHC diet increased PLIN3 protein expression and redistributed PLIN2 to lipid droplet stores in type I fibres.The HFHC diet increased IMTG content in type I fibres, while lipid metabolite concentrations remained the same. The data suggest that the increases in IMTG stores assists in reducing the accumulation of lipid metabolites known to contribute to skeletal muscle insulin resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
12. Significance of number of positive lymph nodes and size as prognostic factors of recurrence and overall survival in cervical cancer patients.
- Author
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Attiah, D. G., Helenowski, I., Refaat, T., Strauss, J. B., Shahabi, S., Lurain, J., Pineda, M., Nieves-Neira, W., Matei, D., and Donnelly, E. D.
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CERVICAL cancer ,LYMPH nodes ,PROGNOSTIC tests ,RADIOISOTOPE brachytherapy ,RADIATION - Abstract
Objectives: Although not included in the formal staging of cervical cancer, lymph node status is a known prognostic factor that greatly impacts survival. The aim of this study was to investigate the number and size of positive lymph nodes as independent prognostic factors of disease recurrence and overall survival (OS) in cervical cancer patients undergoing definitive chemo-radiation therapy (CRT). Materials and Methods: The present authors reviewed the clinical data of eligible women with loco-regionally confined, Stages IB1 through IVA, intact cervical cancer who received definitive CRT at Northwestern Memorial Hospital between January 1997 and September 2009. All women underwent definitive CRT with combined external beam radiation and brachytherapy. Probabilities for risk of recurrence were calculated relative to clinico-pathological variables. OS rates were obtained via the Kaplan-Meier method and differences between groups were analyzed using the log-rank test. Results: The authors identified 109 women during the study period with cervical cancer Stages IB1 through IVA treated definitively with CRT who met all inclusion criteria. The incidence of positive lymph nodes in the entire patient population was 42% (46 out of 109 cases). Advanced tumor stage was significantly associated with an increase in number of metastatic nodes (p = 0.02) and lymph node size (p = 0.04). The number of positive lymph nodes at the time of diagnosis was found to significantly impact risk of recurrence (p = 0.03). The present analysis revealed that patients with only one positive lymph node had a significantly lower risk of recurrence than those with >1 nodes, 25% vs. 58% (p = 0.04). Comparatively, lymph node size had no significant influence on recurrence (p = 0.45). Conclusion: Incremental increases in metastatic lymph node number at time of diagnosis correlated with worsening loco-regional control and OS. On the contrary, lymph node size was not found to be an independent prognostic factor for recurrence or survival. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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13. Seed-Drill Opener Type and Crop Residue Load Affect Canola Establishment, but Only Residue Load Affects Yield.
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Swanepoel, P. A., le Roux, P. J. G., Agenbag, G. A., Strauss, J. A., and MacLaren, C.
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CROP residues ,CANOLA ,MEDITERRANEAN climate ,PLANT populations ,GRAIN yields ,OILSEEDS ,CROP rotation - Abstract
Handling crop residue during planting operations is a challenge to conservation agriculture (CA) farmers worldwide. It remains unclear which tools are most effective in which conditions. Canola (Brassica napus L.), an oilseed crop widely used in rotation with cereals, is particularly sensitive to seedbed conditions, and thus may be influenced by residue loads and the choice of seed-drill openers. To identify optimal planting practices, this study compared the performance of disc and tine openers on canola establishment, growth, and yield under differing residue loads in a Mediterranean-type climate region. First, soil disturbance caused by disc and tine openers was evaluated to assess their effect on seedbed conditions; and second, the interacting effects of the openers with different residue loads was investigated. Tine openers and low crop residue loads resulted in the best (P < 0.05) canola establishment. However, canola at reduced plant populations compensated in both biomass and grain yield, so that no yield differences resulted from different opener types, and only small yield differences occurred between residue loads (P > 0.05). [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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14. An Analytic Model of the Hasp Execution Task Monitor.
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Strauss, J. C.
- Subjects
COMPUTER systems ,COMPUTER storage devices ,MATHEMATICAL models ,RANDOM access memory ,COMPUTER monitors ,COMPUTER terminals - Abstract
The HASP Execution Task Monitor periodically rearranges the OS/360 dispatching chain to give tasks preemptive execution priority in inverse order to that of their cpu utilization history. The effect is to keep the I/O bound tasks active and to prevent cpu bound tasks from locking out other tasks. This paper develops a simple model of the Execution Task Monitor and employs it to study the effectiveness of the monitor in improving system performance. A modified strategy for monitor control is investigated for the case of task execution in a memory heirarchy of varying speeds. [ABSTRACT FROM AUTHOR]
- Published
- 1974
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15. LETTERS.
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KROGER, DON, CONLON, JHON P., PAPROCKI, JOSEPH S., ROBERTS, CARL M., KIPLEY, MAXINE, GORMLEY, M. K., DOOLEY, G. K., DUNN, J. NORTON, DETLEFSEN, HAROLD H., Clark Jr, Harvey, MICHAEL, HAROLD L., REDMAN, CHARLES B., ROTH, ROBERT B., DE NOBRIGA, FRANK H., WALLACE, H. O., STEVENSON, FRED L., PORTER, CHARLES H., and STRAUSS, J. M.
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LETTERS to the editor ,LIQUORS ,DISABILITY laws - Abstract
Several letters to the editor are presented in response to articles in previous issues including one about liquor and Pearl Harbor in the August 20, 1951 issue, another about the disability bill in the August 27, 1951 issue, and the article "The Case Against Ike" in the August 20, 1951 issue.
- Published
- 1951
16. Training alters the distribution of perilipin proteins in muscle following acute free fatty acid exposure.
- Author
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Shepherd, S. O., Strauss, J. A., Wang, Q., Dube, J. J., Goodpaster, B., Mashek, D. G., and Chow, L. S.
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PERILIPIN ,FREE fatty acids ,GLYCEROLIPIDS ,GLUCOSE clamp technique ,LIPIDOSES - Abstract
Key points The lipid droplet (LD)-associated perilipin (PLIN) proteins promote intramuscular triglyceride (IMTG) storage, although whether the abundance and association of the PLIN proteins with LDs is related to the diverse lipid storage in muscle between trained and sedentary individuals is unknown., We show that lipid infusion augments IMTG content in type I fibres of both trained and sedentary individuals. Most importantly, despite there being no change in PLIN protein content, lipid infusion did increase the number of LDs connected with PLIN proteins in trained individuals only., We conclude that trained individuals are able to redistribute the pre-existing pool of PLIN proteins to an expanded LD pool during lipid infusion and, via this adaptation, may support the storage of fatty acids in IMTG., Abstract Because the lipid droplet (LD)-associated perilipin (PLIN) proteins promote intramuscular triglyceride (IMTG) storage, we investigated the hypothesis that differential protein content of PLINs and their distribution with LDs may be linked to the diverse lipid storage in muscle between trained and sedentary individuals. Trained ( n = 11) and sedentary ( n = 10) subjects, matched for age, sex and body mass index, received either a 6 h lipid or glycerol infusion in the setting of a concurrent hyperinsulinaemic-euglycaemic clamp. Sequential muscle biopsies (0, 2 and 6 h) were analysed using confocal immunofluorescence microscopy for fibre type-specific IMTG content and PLIN associations with LDs. In both groups, lipid infusion increased IMTG content in type I fibres (trained: +62%, sedentary: +79%; P < 0.05) but did not affect PLIN protein content. At baseline, PLIN2 (+65%), PLIN3 (+105%) and PLIN5 (+53%; all P < 0.05) protein content was higher in trained compared to sedentary individuals. In trained individuals, lipid infusion increased the number of LDs associated with PLIN2 (+27%), PLIN3 (+73%) and PLIN5 (+40%; all P < 0.05) in type I fibres. By contrast, in sedentary individuals, lipid infusion only increased the number of LDs not associated with PLIN proteins. Acute free fatty acid elevation therefore induces a redistribution of PLIN proteins to an expanded LD pool in trained individuals only and this may be part of the mechanism that enables fatty acids to be stored in IMTG. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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17. Evolutionary diversification of the auditory organ sensilla in Neoconocephalus katydids (Orthoptera: Tettigoniidae) correlates with acoustic signal diversification over phylogenetic relatedness and life history.
- Author
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Strauß, J., Alt, J. A., Ekschmitt, K., Schul, J., and Lakes‐Harlan, R.
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EVOLUTION of the ear ,ACOUSTIC signal detection ,SEXUAL selection ,TYMPANAL organ ,TETTIGONIIDAE ,INSECTS - Abstract
Neoconocephalus Tettigoniidae are a model for the evolution of acoustic signals as male calls have diversified in temporal structure during the radiation of the genus. The call divergence and phylogeny in Neoconocephalus are established, but in tettigoniids in general, accompanying evolutionary changes in hearing organs are not studied. We investigated anatomical changes of the tympanal hearing organs during the evolutionary radiation and divergence of intraspecific acoustic signals. We compared the neuroanatomy of auditory sensilla ( crista acustica) from nine Neoconocephalus species for the number of auditory sensilla and the crista acustica length. These parameters were correlated with differences in temporal call features, body size, life histories and different phylogenetic positions. By this, adaptive responses to shifting frequencies of male calls and changes in their temporal patterns can be evaluated against phylogenetic constraints and allometry. All species showed well-developed auditory sensilla, on average 32-35 between species. Crista acustica length and sensillum numbers correlated with body size, but not with phylogenetic position or life history. Statistically significant correlations existed also with specific call patterns: a higher number of auditory sensilla occurred in species with continuous calls or slow pulse rates, and a longer crista acustica occurred in species with double pulses or slow pulse rates. The auditory sensilla show significant differences between species despite their recent radiation, and morphological and ecological similarities. This indicates the responses to natural and sexual selection, including divergence of temporal and spectral signal properties. Phylogenetic constraints are unlikely to limit these changes of the auditory systems. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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18. Diagnostische und interventionelle Eingriffe im Kindesalter : Anästhesiologisches Management.
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Becke K, Landsleitner B, Reinhold P, Schmitz B, Strauss J, Philippi-Höhne C, Becke, K, Landsleitner, B, Reinhold, P, Schmitz, B, Strauss, J, and Philippi-Höhne, C
- Abstract
Diagnostic and interventional procedures in children often need to be performed under sedation. This prevents pain and stress in children and provides optimal examination conditions. For complete immobilization and stress shielding the depth of sedation often corresponds with general anesthesia. Therefore, established safety standards need to be observed and a fundamental precondition is implementation by a skilled anesthesiologist who can handle the anesthesiology procedure and its possible complications. Organization, schedule, medication, equipment, monitoring and post-anesthesiology care should be institutionally defined. A professional anesthesiology management of pediatric patients is an important factor to increase the quality of care, patient safety and patient satisfaction. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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19. Microbial lipid signatures and substrate potential of organic matter in permafrost deposits: Implications for future greenhouse gas production.
- Author
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Stapel, J. G., Schirrmeister, L., Overduin, P. P., Wetterich, S., Strauss, J., Horsfield, B., and Mangelsdorf, K.
- Published
- 2016
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20. Targeting the microenvironment of pancreatic cancer: overcoming treatment barriers and improving local immune responses.
- Author
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Strauss, J., Alewine, C., Figg, W., and Duffy, A.
- Abstract
Historically, patients diagnosed with metastatic pancreatic cancer have faced a grim prognosis. The survival benefit seen with systemic chemotherapies and even combinations thereof have been disappointing. However, growing data suggest that the microenvironment of pancreatic cancer may be contributing to this poor prognosis. This microenvironment has a dense fibrotic stroma, and is hypoxic and highly immunosuppressive, all of which pose barriers to treatment. Newer strategies looking to disrupt the fibrotic stroma, target hypoxic areas, and improve local immune responses in the tumor microenvironment are currently undergoing clinical evaluation and seem to offer great promise. In addition to these therapies, preclinical work evaluating novel cytotoxic agents including nanoparticles has also been encouraging. While much research still needs to be done, these strategies offer new hope for patients with pancreatic cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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21. Observation-based modelling of permafrost carbon fluxes with accounting for deep carbon deposits and thermokarst activity.
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von Deimling, T. Schneider, Grosse, G., Strauss, J., Schirrmeister, L., Morgenstern, A., Schaphoff, S., Meinshausen, M., and Boike, J.
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PERMAFROST ,THERMOKARST ,SLACKWATER deposits ,CARBON dioxide & the environment ,METHANE & the environment ,ATMOSPHERIC temperature - Abstract
High-latitude soils store vast amounts of perennially frozen and therefore inert organic matter. With rising global temperatures and consequent permafrost degradation, a part of this carbon stock will become available for microbial decay and eventual release to the atmosphere. We have developed a simplified, two-dimensional multi-pool model to estimate the strength and timing of future carbon dioxide (CO
2 ) and methane (CH4 ) fluxes from newly thawed permafrost carbon (i.e. carbon thawed when temperatures rise above pre-industrial levels). We have especially simulated carbon release from deep deposits in Yedoma regions by describing abrupt thaw under newly formed thermokarst lakes. The computational efficiency of our model allowed us to run large, multi-centennial ensembles under various scenarios of future warming to express uncertainty inherent to simulations of the permafrost carbon feedback. Under moderate warming of the representative concentration pathway (RCP) 2.6 scenario, cumulated CO2 fluxes from newly thawed permafrost carbon amount to 20 to 58 peta-grams of carbon (Pg-C) (68 % range) by the year 2100 and reach 40 to 98 Pg-C in 2300. The much larger permafrost degradation under strong warming (RCP8.5) results in cumulated CO2 release of 42 to 141 Pg-C and 157 to 313 Pg-C (68% ranges) in the years 2100 and 2300, respectively. Our estimates only consider fluxes from newly thawed permafrost, not from soils already part of the seasonally thawed active layer under pre-industrial climate. Our simulated CH4 fluxes contribute a few percent to total permafrost carbon release yet they can cause up to 40 % of total permafrost-affected radiative forcing in the 21st century (upper 68% range). We infer largest CH4 emission rates of about 50 Tg-CH4 per year around the middle of the 21st century when simulated thermokarst lake extent is at its maximum and when abrupt thaw under thermokarst lakes is taken into account. CH4 release from newly thawed carbon in wetland-affected deposits is only discernible in the 22nd and 23rd century because of the absence of abrupt thaw processes. We further show that release from organic matter stored in deep deposits of Yedoma regions crucially affects our simulated circumpolar CH4 fluxes. The additional warming through the release from newly thawed permafrost carbon proved only slightly dependent on the pathway of anthropogenic emission and amounts to about 0.03-0.14 °C (68 % ranges) by end of the century. The warming increased further in the 22nd and 23rd century and was most pronounced under the RCP6.0 scenario, adding 0.16 to 0.39 °C (68% range) to simulated global mean surface air temperatures in the year 2300. [ABSTRACT FROM AUTHOR]- Published
- 2015
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22. Organic-matter quality of deep permafrost carbon -- a study from Arctic Siberia.
- Author
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Strauss, J., Schirrmeister, L., Mangelsdorf, K., Eichhorn, L., Wetterich, S., and Herzschuh, U.
- Subjects
PERMAFROST ,ORGANIC compounds ,CARBON ,PLEISTOCENE Epoch ,HOLOCENE Epoch - Abstract
The organic-carbon (OC) pool accumulated in Arctic permafrost (perennially frozen ground) equals the carbon stored in the modern atmosphere. To give an idea of how Yedoma region permafrost could respond under future climatic warming, we conducted a study to quantify the organic-matter quality (here defined as the intrinsic potential to be further transformed, decomposed, and mineralized) of late Pleistocene (Yedoma) and Holocene (thermokarst) deposits on the Buor-Khaya Peninsula, northeast Siberia. The objective of this study was to develop a stratigraphic classified organic-matter quality characterization. For this purpose the degree of organic-matter decomposition was estimated by using a multiproxy approach. We applied sedimentological (grain-size analyses, bulk density, ice content) and geochemical parameters (total OC, stable carbon isotopes (δ
13 C), total organic carbon : nitrogen (C/ N) ratios) as well as lipid biomarkers (n-alkanes, n-fatty acids, hopanes, triterpenoids, and biomarker indices, i.e., average chain length, carbon preference index (CPI), and higher-plant fatty-acid index (HPFA)). Our results show that the Yedoma and thermokarst organic-matter qualities for further decomposition exhibit no obvious degradation--depth trend. Relatively, the C/ N and (δ13 C values and the HPFA index show a significantly better preservation of the organic matter stored in thermokarst deposits compared to Yedoma deposits. The CPI data suggest less degradation of the organic matter from both deposits, with a higher value for Yedoma organic matter. As the interquartile ranges of the proxies mostly overlap, we interpret this as indicating comparable quality for further decomposition for both kinds of deposits with likely better thermokarst organic-matter quality. Supported by principal component analyses, the sediment parameters and quality proxies of Yedoma and thermokarst deposits could not be unambiguously separated from each other. This revealed that the organic-matter vulnerability is heterogeneous and depends on different decomposition trajectories and the previous decomposition and preservation history. Elucidating this was one of the major new contributions of our multiproxy study. With the addition of biomarker data, it was possible to show that permafrost organic-matter degradation likely occurs via a combination of (uncompleted) degradation cycles or a cascade of degradation steps rather than as a linear function of age or sediment facies. We conclude that the amount of organic matter in the studied sediments is high for mineral soils and of good quality and therefore susceptible to future decomposition. The lack of depth trends shows that permafrost acts like a giant freezer, preserving the constant quality of ancient organic matter. When undecomposed Yedoma organic matter is mobilized via thermokarst processes, the fate of this carbon depends largely on the environmental conditions; the carbon could be preserved in an undecomposed state till refreezing occurs. If modern input has occurred, thermokarst organic matter could be of a better quality for future microbial decomposition than that found in Yedoma deposits. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
23. Perioperative Hämotherapie bei Neugeborenen und Kindern.
- Author
-
Strauß, J.
- Published
- 2014
- Full Text
- View/download PDF
24. Optimisation of a transverse flux linear oscillating generator by transient 3D finite element analysis.
- Author
-
Joubert, L. H. and Strauss, J. M.
- Published
- 2014
- Full Text
- View/download PDF
25. Design optimisation of a transverse flux, short stroke, linear generator.
- Author
-
Joubert, L. H., Schutte, J., Strauss, J. M., and Dobson, R. T.
- Abstract
This study entails the design optimisation of a tubular, transverse flux, reciprocating linear electric generator for short stroke, high frequency applications — more specifically with resonant free-piston Stirling engines. Gradient-based iterative dimensional optimisation was performed using a static three-dimensional finite element analysis in order to determine the most suitable design. The electromagnetically active mass of the generator was minimised while maintaining certain power output and efficiency levels. Three consecutive optimisations were performed with increasing degrees of freedom to investigate the influence thereof on the mass of the generator. The final design is considered to be an improvement on previous efforts. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
26. Constrained optimisation of a transverse flux PM linear generator.
- Author
-
Schutte, J., Joubert, L. H., and Strauss, J. M.
- Abstract
This article reports on a finite element analysis assisted optimisation strategy for a moving magnet, transverse flux, short stroke linear generator for free-piston Stirling engine applications. The optimisation goal was to maximise the power-to-weight ratio while maintaining pre-set power and efficiency levels. The topology and the implementation of the optimisation strategy are discussed, followed by a comparison between simulated and measured results for a 3 kW prototype. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
27. Comparison of surgical procedures for degenerative lumbar spinal stenosis: a meta-analysis of the literature from 1975 to 1995.
- Author
-
Niggemeyer, O., Strauss, J., Schulitz, K., Strauss, J M, and Schulitz, K P
- Abstract
Therapy for spinal stenosis remains difficult. The possibilities for conservative management are limited and not satisfactory in the more severe cases. Various surgical procedures are possible, such as decompression, decompression and fusion without instrumentation and decompression and fusion with instrumentation. The aim of our meta-analysis was to compare the postoperative results of these three surgical techniques in the literature and, thus, to establish a treatment of choice for degenerative lumbar spinal stenosis. Via Medline, 30 articles met the inclusion criteria for our study, leading to a total number of 1668 cases being included in the meta-analysis. The evaluation was made according to our own definition of outcomes, based on criteria most commonly used in the studies reviewed. We found that in patients suffering degenerative spinal stenosis for up to 8 years, decompression without fusion showed the best results. For a duration of symptoms of 15 years or more, decompression with instrumented fusion had the best results. Analysing all postoperative outcomes, decompression is the surgical procedure with the highest rate of success and the fewest complications, followed by decompression with instrumented fusion. In surgery for degenerative lumbar spinal stenosis, decompression and fusion without instrumentation was the least successful procedure. As patients suffering from a degenerative spinal stenosis often are elderly, operations are risky and place a strain on them. This review of the literature shows that the least invasive surgical procedure can obtain the best results if the correct diagnosis is made and if the operation is carried out within the first years of the disease. [ABSTRACT FROM AUTHOR]
- Published
- 1997
- Full Text
- View/download PDF
28. Shoulder joint stability after arthroscopic subacromial decompression.
- Author
-
Schneider, T., Strauss, J., Hoffstetter, I., Jerosch, J., and Strauss, J M
- Abstract
In 55 patients with type I or type II impingement lesions we performed arthroscopic subacromial decompression. Fifty-two patients are followed up 1 year postoperatively. In all patients the condition of the affected shoulder before and after decompression was documented using a 100-point shoulder score (pain on activity, 15 points; pain without activity, 15 points; function, 20 points; weight lifting, 10 points; muscle strength, 15 points; range of motion, 25 points). At follow-up we also documented the extent of passive inferior shift of the humeral head by ultrasound. The mean score preoperatively was 60.9 (+/- 13.8). Postoperatively there was a significant increase to 84.7 (+/- 12.5). The average postoperative hospital stay was 8.8 days (+/- 2.1). In 12 patients (23%) the postoperative score was less than 85 points, and in these the treatment was considered to have failed. Comparison of these patients as a group with those in whom the treatment was successful revealed no difference in age, a small but not significant difference in the preoperative duration of shoulder complaints, and no difference in the postoperative length of stay in hospital. However, there was a significant difference in the extent of passive inferior shift of the humeral head: in the failure group the mean inferior shift was 4.6 +/- 1.9 mm, while in the other patients the shift was only 2.7 +/- 1.0 mm. This difference was statistically highly significant. There was a statistical highly significant negative Pearson correlation coefficient of -5.56 between postoperative score and inferior shift of the humeral head. We conclude that patients with subacromial pathology and hypermobile glenohumeral joints may not be good candidates for subacromial decompression. [ABSTRACT FROM AUTHOR]
- Published
- 1994
- Full Text
- View/download PDF
29. MyNet: A Platform for Secure P2P Personal and Social Networking Services.
- Author
-
Kalofonos, D.N., Antoniou, Z., Reynolds, F.D., Van-Kleek, M., Strauss, J., and Wisner, P.
- Published
- 2008
- Full Text
- View/download PDF
30. A new wafer level coating technique to reduce the color distribution of LEDs.
- Author
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Braune, B., Petersen, K., Strauss, J., Kromotis, P., and Kaempf, M.
- Published
- 2007
- Full Text
- View/download PDF
31. Simplified Shadow Volumes using Silhouette Level-of-Detail.
- Author
-
Strauss, J. and Datta, A.
- Published
- 2007
- Full Text
- View/download PDF
32. Insulator pollution monitoring program for Namibia.
- Author
-
Vosloo, W.L., Engelbrecht, F., Heger, N., Holtzhausen, J.P., and Strauss, J.
- Published
- 2007
- Full Text
- View/download PDF
33. Light conversion in opto semiconductor devices: from the development of luminous materials to products with customized colors.
- Author
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Braune, B., Brunner, H., Strauss, J., and Petersen, K.
- Published
- 2005
- Full Text
- View/download PDF
34. Improved UMTS base station transmitter featuring high efficiency and integrated analogue parts.
- Author
-
Bitzer, T., Bohn, T., Jacob, G., Jacnecke, P., Luger, J., Pascht, A., Schaepperle, J., Schwoerer, G., and Strauss, J.
- Published
- 2004
- Full Text
- View/download PDF
35. Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps.
- Author
-
Hugelius, G., Strauss, J., Zubrzycki, S., Harden, J. W., Schuur, E. A. G., Ping, C.-L., Schirrmeister, L., Grosse, G., Michaelson, G. J., Koven, C. D., O'Donnell, J. A., Elberling, B., Mishra, U., Camill, P., Yu, Z., Palmtag, J., and Kuhry, P.
- Subjects
PERMAFROST ecosystems ,CARBON in soils ,SOIL heating ,QUANTITATIVE research ,THERMOKARST - Abstract
Soils and other unconsolidated deposits in the northern circumpolar permafrost region store large amounts of soil organic carbon (SOC). This SOC is potentially vulnerable to remobilization following soil warming and permafrost thaw, but SOC stock estimates were poorly constrained and quantitative error estimates were lacking. This study presents revised estimates of permafrost SOC stocks, including quantitative uncertainty estimates, in the 0-3 m depth range in soils as well as for sediments deeper than 3 m in deltaic deposits of major rivers and in the Yedoma region of Siberia and Alaska. Revised estimates are based on significantly larger databases compared to previous studies. Despite this there is evidence of significant remaining regional data gaps. Estimates remain particularly poorly constrained for soils in the High Arctic region and physiographic regions with thin sedimentary overburden (mountains, highlands and plateaus) as well as for deposits below 3 m depth in deltas and the Yedoma region. While some components of the revised SOC stocks are similar in magnitude to those previously reported for this region, there are substantial differences in other components, including the fraction of perennially frozen SOC. Upscaled based on regional soil maps, estimated permafrost region SOC stocks are 217 ± 12 and 472 ± 27 Pg for the 0-0.3 and 0-1 m soil depths, respectively (±95 % confidence intervals). Storage of SOC in 0-3 m of soils is estimated to 1035 ± 150 Pg. Of this, 34 ± 16PgC is stored in poorly developed soils of the High Arctic. Based on generalized calculations, storage of SOC below 3 m of surface soils in deltaic alluvium of major Arctic rivers is estimated as 91±52 Pg. In the Yedoma region, estimated SOC stocks below 3mdepth are 181±54 Pg, of which 74±20 Pg is stored in intact Yedoma (late Pleistocene ice- and organic-rich silty sediments) with the remainder in refrozen thermokarst deposits. Total estimated SOC storage for the permafrost region is ~ 1300 Pg with an uncertainty range of ~ 1100 to 1500 Pg. Of this, ~ 500 Pg is in non-permafrost soils, seasonally thawed in the active layer or in deeper taliks, while ~ 800 Pg is perennially frozen. This represents a substantial ~ 300 Pg lowering of the estimated perennially frozen SOC stock compared to previous estimates. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
36. Observation-based modelling of permafrost carbon fluxes with accounting for deep carbon deposits and thermokarst activity.
- Author
-
von Deimling, T. Schneider, Grosse, G., Strauss, J., Schirrmeister, L., Morgenstern, A., Schaphoff, S., Meinshausen, M., and Boike, J.
- Subjects
CARBON ,THERMOKARST ,ORGANIC compounds ,BIODEGRADATION ,TEMPERATURE effect ,ESTIMATION theory ,FLUX (Energy) - Abstract
High-latitude soils store vast amounts of perennially frozen and therefore inert organic matter. With rising global temperatures and consequent permafrost degradation, a part of this carbon store will become available for microbial decay and eventual release to the atmosphere. We have developed a simplified, two-dimensional multi-pool model to estimate the strength and timing of future carbon dioxide (CO
2 ) and methane (CH4 ) fluxes from newly thawed permafrost carbon (i.e. carbon thawed when temperatures rise above pre-industrial levels). We have especially simulated carbon release from deep deposits in Yedoma regions by describing abrupt thaw under thermokarst lakes. The computational efficiency of our model allowed us to run large, multi-centennial ensembles under various scenarios of future warming to express uncertainty inherent to simulations of the permafrost-carbon feedback. Under moderate warming of the representative concentration pathway (RCP) 2.6 scenario, cumulated CO2 fluxes from newly thawed permafrost carbon amount to 20 to 58 petagrammes of carbon (Pg-C) (68% range) by the year 2100 and reach 40 to 98 Pg-C in 2300. The much larger permafrost degradation under strong warming (RCP8.5) results in cumulated CO2 release of 42-141 and 157-313 Pg-C (68% ranges) in the years 2100 and 2300, respectively. Our estimates do only consider fluxes from newly thawed permafrost but not from soils already part of the seasonally thawed active layer under preindustrial climate. Our simulated methane fluxes contribute a few percent to total permafrost carbon release yet they can cause up to 40 % of total permafrost-affected radiative forcing in the 21st century (upper 68% range). We infer largest methane emission rates of about 50Tg-CH4 year-1 around the mid of the 21st century when simulated thermokarst lake extent is at its maximum and when abrupt thaw under thermokarst lakes is accounted for. CH4 release from newly thawed carbon in wetland-affected deposits is only discernible in the 22nd and 23rd century because of the absence of abrupt thaw processes. We further show that release from organic matter stored in deep deposits of Yedoma regions does crucially affect our simulated circumpolar methane fluxes. The additional warming through the release from newly thawed permafrost carbon proved only slightly dependent on the pathway of anthropogenic emission and amounts about 0.03-0.14°C (68% ranges) by end of the century. The warming increased further in the 22nd and 23rd century and was most pronounced under the RCP6.0 scenario with adding 0.16-0.39°C (68% range) to simulated global mean surface air temperatures in the year 2300. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
37. Organic matter quality of deep permafrost carbon -- a study from Arctic Siberia.
- Author
-
Strauss, J., Schirrmeister, L., Mangelsdorf, K., Eichhorn, L., Wetterich, S., and Herzschuh, U.
- Subjects
ORGANIC compounds ,PERMAFROST ,ATMOSPHERE ,GLOBAL warming ,CLIMATE change ,PLEISTOCENE Epoch - Abstract
The organic carbon (OC) pool accumulated in Arctic permafrost (perennially frozen ground) equals the carbon stored in the recent atmosphere. To give an idea of how Yedoma region permafrost could respond under future climatic warming, we conducted a study to quantify the organic matter quality for future decomposition of late Pleistocene (Yedoma) and Holocene (thermokarst) deposits on the Buor Khaya Peninsula, northeast Siberia. The objective of this study was to develop a stratigraphic classified organic matter quality characterization. For this purpose the degree of organic matter decomposition was estimated by using a multiproxy approach. We applied sedimentological (grain-size analyses, bulk density, ice content) and geochemical parameters (total OC, stable carbon isotopes (δ
13 C), carbon : nitrogen (C/N) ratios) as well as lipid biomarkers (n-alkanes, n-fatty acids, hopanes, triterpenoids, and biomarker proxies/indices: average chain length, carbon preference index (CPI), and higher plant fatty acid index (HPFA)). Our results show that the Yedoma and thermokarst organic matter qualities exhibit no obvious degradation -- depth trend. The C/N, δ13 C, and hop-17(21)-ene values and the HPFA index show a better quality of the organic matter stored in thermokarst deposits compared to Yedoma deposits, but the CPI points in the other direction. As the ranges of the proxies mostly overlap, we interpret this as to indicate similar quality for both kind of deposits with perhaps slightly better thermokarst organic matter quality. Supported by principal component analyses, the sediment parameters and quality proxies of Yedoma and thermokarst deposits could not be clearly separated from each other. This lack of clear quality differences revealed that the organic matter vulnerability is heterogeneous, independent from radiocarbon age and depends on different decomposition trajectories and the previous decomposition and preservation history. Elucidating this was one of the major novelties of our multiproxy study. With the addition of biomarker data, it was possible to show that permafrost organic matter degradation likely occurs via a combination of (uncompleted) degradation cycles or a cascade of degradation steps rather than as a linear function of age or sediment facies. We conclude that the amount of organic matter in the studied sediments is high for mineral soils and of good quality and therefore susceptible to future decomposition. The missing depth trends reveal that permafrost acts like a giant freezer, preserving the constant quality of ancient organic matter independently from its age. When unde-composed Yedoma organic matter is mobilized via thermokarst processes, the fate of this carbon depends largely on the environmental conditions; the carbon could be preserved in an undecomposed state till refreezing occurs. If recent input has occurred, thermokarst organic matter could be of a better quality than that found in Yedoma deposits. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
38. Improved estimates show large circumpolar stocks of permafrost carbon while quantifying substantial uncertainty ranges and identifying remaining data gaps.
- Author
-
Hugelius, G., Strauss, J., Zubrzycki, S., Harden, J. W., Schuur, E. A. G., Ping, C. L., Schirrmeister, L., Grosse, G., Michaelson, G. J., Koven, C. D., O'Donnell, J. A., Elberling, B., Mishra, U., Camill, P., Yu, Z., Palmtag, J., and Kuhry, P.
- Subjects
PERMAFROST ,DATA analysis ,ORGANIC compound content of soils ,SOIL heating ,GEOMORPHOLOGY ,LAND use - Abstract
Soils and other unconsolidated deposits in the northern circumpolar permafrost region store large amounts of soil organic carbon (SOC). This SOC is potentially vulnerable to remobilization following soil warming and permafrost thaw, but stock estimates are poorly constrained and quantitative error estimates were lacking. This study presents revised estimates of the permafrost SOC pool, including quantitative uncertainty estimates, in the 0-3m depth range in soils as well as for deeper sediments (> 3 m) in deltaic deposits of major rivers and in the Yedoma region of Siberia and Alaska. The revised estimates are based on significantly larger databases compared to previous studies. Compared to previous studies, the number of individual sites/pedons has increased by a factor x 8-11 for soils in the 1-3 m depth range,, a factor x 8 for deltaic alluvium and a factor x 5 for Yedoma region deposits. Upscaled based on regional soil maps, estimated permafrost region SOC stocks are 217 ± 15 and 472 ± 34 Pg for the 0-0.3 m and 0-1 m soil depths, respectively (±95% confidence intervals). Depending on the regional subdivision used to upscale 1-3 m soils (following physiography or continents), estimated 0-3 m SOC storage is 1034 ± 183 Pg or 1104 ± 133 Pg. Of this, 34 ± 16 Pg C is stored in thin soils of the High Arctic. Based on generalised calculations, storage of SOC in deep deltaic alluvium (>3m to ≤60 m depth) of major Arctic rivers is estimated to 91 ± 39 Pg (of which 69 ± 34 Pg is in permafrost). In the Yedoma region, estimated >3m SOC stocks are 178+140/-146 Pg, of which 74+54/-57 Pg is stored in intact, frozen Yedoma (late Pleistocene ice- and organic-rich silty sediments) with the remainder in refrozen thermokarst deposits (±16/84th percentiles of bootstrapped estimates). A total estimated mean storage for the permafrost region of ca. 1300-1370 Pg with an uncertainty range of 930-1690 Pg encompasses the combined revised estimates. Of this, ≤819-836 Pg is perennially frozen. While some components of the revised SOC stocks are similar in magnitude to those previously reported for this region, there are also substantial differences in individual components. There is evidence of remaining regional data-gaps. Estimates remain particularly poorly constrained for soils in the High Arctic region and physiographic regions with thin sedimentary overburden (mountains, highlands and plateaus) as well as for >3m depth deposits in deltas and the Yedoma region. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
39. Sensory evolution of hearing in tettigoniids with differing communication systems.
- Author
-
Strauß, J., Lehmann, A. W., and Lehmann, G. U. C.
- Subjects
SENSORY evaluation ,BIOLOGICAL evolution ,HEARING disorders ,TETTIGONIIDAE ,ANIMAL communication ,PHONOTACTICS ,GAME calling (Hunting) ,AUDITORY perception - Abstract
In Tettigoniidae ( Orthoptera: Ensifera), hearing organs are essential in mate detection. Male tettigoniids usually produce calling songs by tegminal stridulation, whereas females approach the males phonotactically. This unidirectional communication system is the most common one among tettigoniids. In several tettigoniid lineages, females have evolved acoustic replies to the male calling song which constitutes a bidirectional communication system. The genus Poecilimon ( Tettigoniidae: Phaneropterinae) is of special interest because the ancestral state of bidirectional communication, with calling males and responding females, has been reversed repeatedly to unidirectional communication. Acoustic communication is mediated by hearing organs that are adapted to the conspecific signals. Therefore, we analyse the auditory system in the Tettigoniidae genus Poecilimon for functional adaptations in three characteristics: (i) dimension of sound-receiving structures (tympanum and acoustic spiracle), (ii) number of auditory sensilla and (iii) hearing sensitivity. Profound differences in the auditory system correlate with uni- or bidirectional communication. Among the sound-receiving structures, the tympana scale with body size, whereas the acoustic spiracle, the major sound input structure, was drastically reduced in unidirectional communicating species. In the unidirectional P. ampliatus group, auditory sensilla are severely reduced in numbers, but not in the unidirectional P. propinquus group. Within the P. ampliatus group, the number of auditory sensilla is further reduced in P. intermedius which lost acoustic signalling due to parthenogenesis. The auditory sensitivity correlated with the size of the acoustic spiracle, as hearing sensitivity was better with larger spiracles, especially in the ultrasonic range. Our results show a significant reduction in auditory structures, shaped by the differing sex roles during mate detection. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
40. The impact of temperature on marine phytoplankton resource allocation and metabolism.
- Author
-
Toseland, A., Moulton, V., Daines, S. J., Clark, J. R., Lenton, T. M., Kirkham, A., Strauss, J., Mock, T., Uhlig, C., Valentin, K., and Pearson, G. A.
- Subjects
MARINE phytoplankton ,EFFECT of temperature on plants ,BIOGEOCHEMICAL cycles ,RESOURCE allocation ,METABOLISM - Abstract
Marine phytoplankton are responsible for ∼50% of the CO
2 that is fixed annually worldwide, and contribute massively to other biogeochemical cycles in the oceans. Their contribution depends significantly on the interplay between dynamic environmental conditions and the metabolic responses that underpin resource allocation and hence biogeochemical cycling in the oceans. However, these complex environment-biome interactions have not been studied on a larger scale. Here we use a set of integrative approaches that combine metatranscriptomes, biochemical data, cellular physiology and emergent phytoplankton growth strategies in a global ecosystems model, to show that temperature significantly affects eukaryotic phytoplankton metabolism with consequences for biogeochemical cycling under global warming. In particular, the rate of protein synthesis strongly increases under high temperatures even though the numbers of ribosomes and their associated rRNAs decreases. Thus, at higher temperatures, eukaryotic phytoplankton seem to require a lower density of ribosomes to produce the required amounts of cellular protein. The reduction of phosphate-rich ribosomes in warmer oceans will tend to produce higher organismal nitrogen (N) to phosphate (P) ratios, in turn increasing demand for N with consequences for the marine carbon cycle due to shifts towards N-limitation. Our integrative approach suggests that temperature plays a previously unrecognized, critical role in resource allocation and marine phytoplankton stoichiometry, with implications for the biogeochemical cycles that they drive. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
41. Ex-utero-intrapartum-treatment-Manöver.
- Author
-
Lehmann, S., Blödow, A., Flügel, W., Renner-Lützkendorf, H., Isbruch, A., Siegling, F., Untch, M., Strauß, J., and Bloching, M.B.
- Abstract
Copyright of HNO is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2013
- Full Text
- View/download PDF
42. A new data set for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region.
- Author
-
Hugelius, G., Bockheim, J. G., Camill, P., Elberling, B., Grosse, G., Harden, J. W., Johnson, K., Jorgenson, T., Koven, C. D., Kuhry, P., Michaelson, G., Mishra, U., Palmtag, J., Ping, C.-L., O'Donnell, J., Schirrmeister, L., Schuur, E. A. G., Y. Sheng, Smith, L. C., and Strauss, J.
- Subjects
CARBON cycle ,CARBON in soils ,PERMAFROST ecosystems ,GEOGRAPHIC information systems ,GROUND ice - Abstract
The article presents research on a data set for the estimation of organic carbon storage in soils up to a depth of three meters in the northern circumpolar permafrost region. Topics include the role of high-latitude terrestrial ecosystems in the global carbon cycle, the use of the Northern Circumpolar Soil Carbon Database (NCSCD) geographical information system (GIS) to quantify soil organic carbon (SOC) levels, and soil classification through GIS mapping.
- Published
- 2013
- Full Text
- View/download PDF
43. Pädiatrische Ertrinkungsunfälle unter verschiedenen äußeren Bedingungen mit unterschiedlichem Outcome.
- Author
-
Heyder-Musolf, J., Simmank, V., and Strauß, J.
- Abstract
Copyright of Notfall & Rettungsmedizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2013
- Full Text
- View/download PDF
44. Anästhetikainduzierte Neurotoxizität : Stellungnahme der Wissenschaftlichen Arbeitskreise Kinderanästhesie und Neuroanästhesie.
- Author
-
Becke, K, Schreiber, M, Philippi-Höhne, C, Strauß, J, Engelhard, K, and Sinner, B
- Published
- 2013
- Full Text
- View/download PDF
45. Anästhetikainduzierte Neurotoxizität.
- Author
-
Becke, K., Schreiber, M., Philippi-Höhne, C., Strauß, J., Engelhard, K., and Sinner, B.
- Subjects
ANESTHESIA ,NEUROTOXICOLOGY ,BRAIN damage ,NEURAL development ,ANIMAL models in research ,APOPTOSIS - Published
- 2013
- Full Text
- View/download PDF
46. Germ cell-specific disruption of the Meig1 gene causes impaired spermiogenesis in mice.
- Author
-
Teves, M. E., Jha, K. N., Song, J., Nagarkatti‐Gude, D. R., Herr, J. C., Foster, J. A., Strauss, J. F., and Zhang, Z.
- Subjects
MEIOSIS ,SPERMIOGENESIS in animals ,GERM cells ,GENE expression ,ANTI-Mullerian hormone ,SERTOLI cells - Abstract
Meiosis expressed gene 1 (Meig1) was originally identified in a search for mammalian genes potentially involved in meiosis. Seven mouse Meig1 transcripts with the same coding region, but different 5'-UTRs, have been identified. These transcripts have different tissue distributions, two are only present in the testis. In the testis, Meig1 is present in germ cells and Sertoli cells. A Meig1 conditional knockout model has been generated. When Meig1 was inactivated globally by crossing with Cmv-Cre transgenic mice, the Meig1-deficient males were sterile due to severe spermiogenic defects, and had no obvious defects in meiosis. To further study its role in individual cell types in the testis, the Meig1
flox mice were crossed with Hsp2a-Cre, Prm-Cre, and Amh-Cre mice, in which the Cre recombinase is driven by the heat shock protein 2 (Hsp2a) gene promoter (expressed in spermatocytes), the protamine 1 gene promoter (expressed in post-meiotic spermatids) and the anti-Mullerian hormone (Amh) gene promoter (expressed in Sertoli cells) respectively. Both Meig1 mRNA and protein were undetectable in testis of the Hsp2a-Cre; Meig1flox/flox mice and all the mutant adult males tested were sterile. This phenotype mirrors that of the Cmv-Cre; Meig1flox/flox mice. Even though the total testicular Meig1 mRNA and protein expression levels were dramatically reduced in testis of the Prm-Cre; Meig1flox/flox males, all the mice tested were fertile, and there was no significant difference in sperm count and sperm motility compared with age-matched Meig1flox/flox male mice. Disruption of Meig1 in the Sertoli cells did not affect the MEIG1 protein expression. Amh-Cre; Meig1flox/flox males were fertile, and produced the same amount of spermatozoa as age-matched Meig1flox/flox mice. The testicular histology was also normal. Our results indicate that MEIG1 regulates spermiogenesis through effects in germ cells alone, and that the Meig1 gene must be active during a discrete period in spermatogenesis after which it is dispensable. [ABSTRACT FROM AUTHOR]- Published
- 2013
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47. Impact of FTO genotypes on BMI and weight in polycystic ovary syndrome: a systematic review and meta-analysis.
- Author
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Wojciechowski, P., Lipowska, A., Rys, P., Ewens, K., Franks, S., Tan, S., Lerchbaum, E., Vcelak, J., Attaoua, R., Straczkowski, M., Azziz, R., Barber, T., Hinney, A., Obermayer-Pietsch, B., Lukasova, P., Bendlova, B., Grigorescu, F., Kowalska, I., Goodarzi, M., and Strauss, J.
- Abstract
Aims/hypothesis: FTO gene single nucleotide polymorphisms (SNPs) have been shown to be associated with obesity-related traits and type 2 diabetes. Several small studies have suggested a greater than expected effect of the FTO rs9939609 SNP on weight in polycystic ovary syndrome (PCOS). We therefore aimed to examine the impact of FTO genotype on BMI and weight in PCOS. Methods: A systematic search of medical databases (PubMed, EMBASE and Cochrane CENTRAL) was conducted up to the end of April 2011. Seven studies describing eight distinct PCOS cohorts were retrieved; seven were genotyped for SNP rs9939609 and one for SNP rs1421085. The per allele effect on BMI and body weight increase was calculated and subjected to meta-analysis. Results: A total of 2,548 women with PCOS were included in the study; 762 were TT homozygotes, 1,253 had an AT/CT genotype, and 533 were AA/CC homozygotes. Each additional copy of the effect allele (A/C) increased the BMI by a mean of 0.19 z score units (95% CI 0.13, 0.24; p = 2.26 × 10) and body weight by a mean of 0.20 z score units (95% CI 0.14, 0.26; p = 1.02 × 10). This translated into an approximately 3.3 kg/m increase in BMI and an approximately 9.6 kg gain in body weight between TT and AA/CC homozygotes. The association between FTO genotypes and BMI was stronger in the cohorts with PCOS than in the general female populations from large genome-wide association studies. Deviation from an additive genetic model was observed in heavier populations. Conclusions/interpretation: The effect of FTO SNPs on obesity-related traits in PCOS seems to be more than two times greater than the effect found in large population-based studies. This suggests an interaction between FTO and the metabolic context or polygenic background of PCOS. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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48. Preoperative administration of etoricoxib in patients undergoing hip replacement causes inhibition of inflammatory mediators and pain relief.
- Author
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Renner, B., Walter, G., Strauss, J., Fromm, M.F., Zacher, J., and Brune, K.
- Abstract
Objective Administering cyclooxygenase-2 inhibitors preoperatively appears attractive since these drugs reduce post-operative pain, but do not increase the risk of post-operative bleeds, asthmatic attacks and stress-related gastrointestinal ulcers. In a former investigation, we could show that post-operative administration of etoricoxib reduces prostaglandin production in wound fluid, but the onset of action is variable due to delayed post-operative absorption. Methods In this study, we investigated the preoperative administration of etoricoxib in patients undergoing hip replacement. They received 120 mg etoricoxib or placebo 2 h before surgery and 1 day after in a double-blinded, randomized, parallel group design. Results A total of 11 patients were randomized (placebo n = 5; verum n = 6). We found high and constant levels of the drug in blood, central nervous system and wound fluid already at the end of surgery (t
max < 2 h). This was accompanied by inhibition of prostaglandin production in the wound tissue (treatment p < 0.05), suppression of interleukin 6 increase in plasma (treatment p < 0.01), and - despite existing standard pain relief procedures - higher satisfaction with analgesics (time vs. treatment p < 0.05) and less demand for opioids (treatment p < 0.01) and intrathecal bupivacaine (treatment p = 0.05) administration. Conclusion Administration of etoricoxib 2 h before surgery allows for an effective drug concentration in critical tissues, a reduction of the production of pro-inflammatory mediators and for better pain relief. [ABSTRACT FROM AUTHOR]- Published
- 2012
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49. A multi-tissue analysis identifies HLA complex group 9 gene methylation differences in bipolar disorder.
- Author
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Kaminsky, Z, Tochigi, M, Jia, P, Pal, M, Mill, J, Kwan, A, Ioshikhes, I, Vincent, J B, Kennedy, J L, Strauss, J, Pai, S, Wang, S-C, and Petronis, A
- Subjects
EPIGENETICS ,DNA methylation ,HLA histocompatibility antigens ,BIPOLAR disorder ,NUCLEOTIDE sequence - Abstract
Epigenetic studies of DNA and histone modifications represent a new and important activity in molecular investigations of human disease. Our previous epigenome-wide scan identified numerous DNA methylation differences in post-mortem brain samples from individuals affected with major psychosis. In this article, we present the results of fine mapping DNA methylation differences at the human leukocyte antigen (HLA) complex group 9 gene (HCG9) in bipolar disorder (BPD). Sodium bisulfite conversion coupled with pyrosequencing was used to interrogate 28 CpGs spanning ∼700 bp region of HCG9 in 1402 DNA samples from post-mortem brains, peripheral blood cells and germline (sperm) of bipolar disease patients and controls. The analysis of nearly 40 000 CpGs revealed complex relationships between DNA methylation and age, medication as well as DNA sequence variation (rs1128306). Two brain tissue cohorts exhibited lower DNA methylation in bipolar disease patients compared with controls at an extended HCG9 region (P=0.026). Logistic regression modeling of BPD as a function of rs1128306 genotype, age and DNA methylation uncovered an independent effect of DNA methylation in white blood cells (odds ratio (OR)=1.08, P=0.0077) and the overall sample (OR=1.24, P=0.0011). Receiver operating characteristic curve A prime statistics estimated a 69-72% probability of correct BPD prediction from a case vs control pool. Finally, sperm DNA demonstrated a significant association (P=0.018) with BPD at one of the regions demonstrating epigenetic changes in the post-mortem brain and peripheral blood samples. The consistent multi-tissue epigenetic differences at HCG9 argue for a causal association with BPD. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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50. Thoracoscopic repair of congenital diaphragmatic hernia by inflation-assisted bowel reduction, in a resuscitated neonate: a better access?
- Author
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Schaarschmidt, K., Strauß, J., Kolberg-Schwerdt, A., Lempe, M., Schlesinger, F., Jaeschke, U., and Strauss, J
- Subjects
DIAPHRAGMATIC hernia ,HUMAN abnormalities ,NEONATAL diseases ,ENDOSCOPIC surgery ,NEONATAL surgery - Abstract
Elective endoscopic diaphragmatic hernia repairs have been reported. But endoscopic surgery was regarded unsuitable for emergency repair of diaphragmatic hernia in ventilated newborn children in bad general condition. We report a new method for inflation-assisted reduction and thoracoscopic repair of congenital diaphragmatic hernia diaphragmatic in a vitally endangered neonate. From three 2.7 mm to 5 mm accesses warmed low-pressure, low-volume CO2 was inflated into the thorax at 100 ml/min and 2 mm mercury. This allowed spontaneous reduction of the thoracic viscera into the abdomen and diaphragmatic suture with minimal handling. The 65-min procedure was tolerated well without perioperative deterioration. The baby was weaned off the respirator and breast-fed within 2 days, mediastinal shift normalized in 6 days. In suitable infants thoracoscopic repair and inflation-assisted reduction of thoracic contents is a more physiological access to congenital diaphragmatic hernia than laparoscopy or laparotomy. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
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