2,781 research outputs found
Evaluation of the users value of salts against apple scab and powdery mildew for fruit production
The research was aimed at finding anti resistance strategies for Integrated fruit growing.
As the salts tested may be approvable for organic farming, the trial results are also of
value for the development of scab an mildew control strategies for organic fruit growing. As
new fungicides are mainly unisite action fungicides, the problem of fungicide resistance
development is becoming more important every year. Combining chemical fungicides,
which is the best anti-resistance strategy, is not always possible or recommended in the
case when the number of available chemical fungicides are limited or a reduction in
fungicide use is asked for. Therefore the use of salts as an anti-resistance strategy was
looked upon. The salts evaluated were K(HCO3), KH2PO3, KHPO4 and K2SiO3. When
using these salts as an anti-resistance strategy the efficacy obtained when spraying the
compounds alone was often to low to be used in rotation with chemical fungicides. Only
with K(HCO3)2 a good efficacy can be observed in some years. The variation in efficacy
with K(HCO3)2 observed is higher for powdery mildew. K(HCO3)2 can be considered as a
ideal product for scab control in organic orchards at moments of low infection risk
Therapie chronischer Wunden mit wassergefiltertem Infrarot A (wIRA)
The central portion of chronic wounds is often hypoxic and relatively hypothermic, representing a deficient energy supply of the tissue, which impedes wound healing or even makes it impossible. Water-filtered infrared-A (wIRA) is a special form of heat radiation with a high tissue penetration and a low thermal load to the skin surface. wIRA produces a therapeutically usable field of heat and increases temperature, oxygen partial pressure and perfusion of the tissue. These three factors are decisive for a sufficient tissue supply with energy and oxygen and consequently as well for wound healing, especially in chronic wounds, and infection defense. wIRA acts both by thermal and thermic as well as by non-thermal and non-thermic effects. wIRA can advance wound healing or improve an impaired wound healing process and can especially enable wound healing in non-healing chronic wounds. wIRA can considerably alleviate the pain and diminish wound exudation and inflammation and can show positive immunomodulatory effects.
In a prospective, randomized, controlled study of 40 patients with chronic venous stasis ulcers of the lower legs irradiation with wIRA and visible light (VIS) accelerated the wound healing process (on average 18 vs. 42 days until complete wound closure, residual ulcer area after 42 days 0.4 cm² vs. 2.8 cm²) and led to a reduction of the required dose of pain medication in comparison to the control group of patients treated with the same standard care (wound cleansing, wound dressing with antibacterial gauze, and compression garment therapy) without the concomitant irradiation.
Another prospective study of 10 patients with non-healing chronic venous stasis ulcers of the lower legs included extensive thermographic investigation. Therapy with wIRA(+VIS) resulted in a complete or almost complete wound healing in 7 patients and a marked reduction of the ulcer size in another 2 of the 10 patients, a clear reduction of pain and required dose of pain medication, and a normalization of the thermographic image.
In a current prospective, randomized, controlled, blinded study patients with non-healing chronic venous stasis ulcers of the lower legs are treated with compression garment therapy, wound cleansing, wound dressings and 30 minutes irradiation five times per week over 9 weeks. A preliminary analysis of the first 23 patients of this study has shown in the group with wIRA(+VIS) compared to a control group with VIS an advanced wound healing, an improved granulation and in the later phase of treatment a decrease of the bacterial burden.
Some case reports have demonstrated that wIRA can also be used for mixed arterial-venous ulcers or arterial ulcers, if irradiation intensity is chosen appropriately low and if irradiation is monitored carefully. wIRA can be used concerning decubital ulcers both in a preventive and in a therapeutic indication. wIRA can improve the resorption of topically applied substances also on wounds.
An irradiation with VIS and wIRA presumably acts with endogenous protoporphyrin IX (or protoporphyrin IX of bacteria) virtually similar as a mild photodynamic therapy (endogenous PDT-like effect). This could lead to improved cell regeneration and wound healing and to antibacterial effects.
In conclusion, these results indicate that wIRA generally should be considered for the treatment of chronic wounds.Das Zentrum von chronischen Wunden ist oft hypoxisch und relativ hypotherm. Dies entspricht einer defizitären Energiebereitstellung im Gewebe, die die Wundheilung behindert oder unmöglich macht. Wassergefiltertes Infrarot A (wIRA) ist eine spezielle Form der Wärmestrahlung mit hohem Eindringvermögen in das Gewebe bei geringer thermischer Oberflächenbelastung. wIRA erzeugt ein therapeutisch nutzbares Wärmefeld und steigert Temperatur, Sauerstoffpartialdruck sowie die Durchblutung im Gewebe. Diese drei Faktoren sind entscheidend für eine ausreichende Versorgung des Gewebes mit Energie und Sauerstoff und deshalb auch für die Wundheilung, speziell bei chronischen Wunden, und die Infektionsabwehr. wIRA wirkt sowohl über thermische und temperaturabhängige als auch über nicht-thermische und temperaturunabhängige Effekte. wIRA kann die Wundheilung beschleunigen oder einen stagnierenden Wundheilungsprozess verbessern und insbesondere bei nicht-heilenden chronischen Wunden eine Wundheilung ermöglichen. wIRA vermag Schmerzen deutlich zu mindern und die Wundsekretion sowie Entzündung zu reduzieren sowie positive immunmodulierende Effekte zu zeigen.
In einer prospektiven, randomisierten, kontrollierten Studie mit 40 Patienten mit chronischen venösen Unterschenkelulzera führte eine Bestrahlung mit wIRA und sichtbarem Licht (VIS) zu einer schnelleren Wundheilung (im Durchschnitt 18 vs. 42 Tage bis zum kompletten Wundschluss, Restulkusfläche nach 42 Tagen 0,4 cm² vs. 2,8 cm²) und einem geringeren Schmerzmittelverbrauch gegenüber einer in gleicher Form (Wundsäuberung, antibakterielle Wundauflagen und Kompressionstherapie) therapierten, aber nicht bestrahlten Kontrollgruppe.
Eine weitere prospektive Studie mit 10 Patienten mit aufwändiger thermographischer Verlaufskontrolle ergab unter Therapie mit wIRA(+VIS) eine vollständige oder fast vollständige Abheilung therapierefraktärer chronischer Unterschenkelulzera bei 7 sowie eine deutliche Ulkusverkleinerung bei 2 weiteren der 10 Patienten, eine ausgeprägte Minderung der Schmerzen und des Schmerzmittelverbrauchs und eine Normalisierung des thermographischen Bildes.
In einer laufenden prospektiven, randomisierten, kontrollierten, verblindeten Studie werden Patienten mit nicht-heilenden chronischen venösen Unterschenkelulzera mit Kompressionstherapie, Wundsäuberung und nicht-adhäsiven Wundauflagen sowie 30 Minuten Bestrahlung fünfmal pro Woche über 9 Wochen behandelt. Eine vorläufige Auswertung der ersten 23 Patienten zeigte, dass die Gruppe mit wIRA(+VIS) verglichen mit einer Kontrollgruppe mit VIS eine schnellere Wundheilung, eine bessere Granulation und in der späteren Phase der Behandlung eine Abnahme der bakteriellen Last der Wunden aufwies.
Einige Fallberichte haben gezeigt, dass wIRA selbst bei gemischt arteriell-venösen Ulzera oder arteriellen Ulzera eingesetzt werden kann, wenn die Bestrahlungsstärke angemessen niedrig gewählt und die Bestrahlung sorgfältig überwacht wird. wIRA kann bei Dekubitalulzera sowohl präventiv als auch therapeutisch eingesetzt werden. wIRA kann die Resorption topisch applizierter Substanzen auch auf Wunden verbessern.
Eine Bestrahlung mit VIS und wIRA wirkt vermutlich in Verbindung mit endogenem Protoporphyrin IX (oder Protoporphyrin IX von Bakterien) quasi ähnlich wie eine milde photodynamische Therapie (endogener PDT-ähnlicher Effekt). Dies kann die Zellregeneration und Wundheilung fördern und antibakteriell wirken.
Zusammengefasst zeigen die Ergebnisse, dass wIRA generell für die Behandlung chronischer Wunden erwogen werden sollte
Bulk-driven non-equilibrium phase transitions in a mesoscopic ring
We study a periodic one-dimensional exclusion process composed of a driven
and a diffusive part. In a mesoscopic limit where both dynamics compete we
identify bulk-driven phase transitions. We employ mean-field theory
complemented by Monte-Carlo simulations to characterize the emerging
non-equilibrium steady states. Monte-Carlo simulations reveal interesting
correlation effects that we explain phenomenologically.Comment: 4 pages, 3 figure
Strontium isotope fractionation in the marine realm: first application for a <sup>87</sup>Sr/<sup>84</sup>Sr-double-spike
Bacteria and fungi respond differently to multifactorial climate change in a temperate heathland, traced with <sup>13</sup>C-Glycine and FACE CO<sub>2</sub>
It is vital to understand responses of soil microorganisms to predicted climate changes, as these directly control soil carbon (C) dynamics. The rate of turnover of soil organic carbon is mediated by soil microorganisms whose activity may be affected by climate change. After one year of multifactorial climate change treatments, at an undisturbed temperate heathland, soil microbial community dynamics were investigated by injection of a very small concentration (5.12 µg C g(-1) soil) of (13)C-labeled glycine ((13)C2, 99 atom %) to soils in situ. Plots were treated with elevated temperature (+1°C, T), summer drought (D) and elevated atmospheric carbon dioxide (510 ppm [CO2]), as well as combined treatments (TD, TCO2, DCO2 and TDCO2). The (13)C enrichment of respired CO2 and of phospholipid fatty acids (PLFAs) was determined after 24 h. (13)C-glycine incorporation into the biomarker PLFAs for specific microbial groups (Gram positive bacteria, Gram negative bacteria, actinobacteria and fungi) was quantified using gas chromatography-combustion-stable isotope ratio mass spectrometry (GC-C-IRMS). Gram positive bacteria opportunistically utilized the freshly added glycine substrate, i.e. incorporated (13)C in all treatments, whereas fungi had minor or no glycine derived (13)C-enrichment, hence slowly reacting to a new substrate. The effects of elevated CO2 did suggest increased direct incorporation of glycine in microbial biomass, in particular in G(+) bacteria, in an ecosystem subjected to elevated CO2. Warming decreased the concentration of PLFAs in general. The FACE CO2 was (13)C-depleted (δ(13)C = 12.2‰) compared to ambient (δ(13)C = ∼-8‰), and this enabled observation of the integrated longer term responses of soil microorganisms to the FACE over one year. All together, the bacterial (and not fungal) utilization of glycine indicates substrate preference and resource partitioning in the microbial community, and therefore suggests a diversified response pattern to future changes in substrate availability and climatic factors
Magnetic fullerenes inside single-wall carbon nanotubes
C59N magnetic fullerenes were formed inside single-wall carbon nanotubes by
vacuum annealing functionalized C59N molecules encapsulated inside the tubes. A
hindered, anisotropic rotation of C59N was deduced from the temperature
dependence of the electron spin resonance spectra near room temperature.
Shortening of spin-lattice relaxation time, T_1, of C59N indicates a reversible
charge transfer toward the host nanotubes above K. Bound C59N-C60
heterodimers are formed at lower temperatures when C60 is co-encapsulated with
the functionalized C59N. In the 10-300 K range, T_1 of the heterodimer shows a
relaxation dominated by the conduction electrons on the nanotubes
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