Regular and chaotic vibration in a piezoelectric energy harvester

We examine regular and chaotic responses of a vibrational energy harvester composed of a vertical beam and a tip mass. The beam is excited horizontally by a harmonic inertial force while mechanical vibrational energy is converted to electrical power through a piezoelectric patch. The mechanical resonator can be described by single or double well potentials depending on the gravity force from the tip mass. By changing the tip mass we examine bifurcations from single well oscillations, to regular and chaotic vibrations between the potential wells. The appearance of chaotic responses in the energy harvesting system is illustrated by the bifurcation diagram, the corresponding Fourier spectra, the phase portraits, and is confirmed by the 0–1 test. The appearance of chaotic vibrations reduces the level of harvested energy

Malignant inflammation in cutaneous T-cell lymphoma: a hostile takeover

Cutaneous T-cell lymphomas (CTCL) are characterized by the presence of chronically inflamed skin lesions containing malignant T cells. Early disease presents as limited skin patches or plaques and exhibits an indolent behavior. For many patients, the disease never progresses beyond this stage, but in approximately one third of patients, the disease becomes progressive, and the skin lesions start to expand and evolve. Eventually, overt tumors develop and the malignant T cells may disseminate to the blood, lymph nodes, bone marrow, and visceral organs, often with a fatal outcome. The transition from early indolent to progressive and advanced disease is accompanied by a significant shift in the nature of the tumor-associated inflammation. This shift does not appear to be an epiphenomenon but rather a critical step in disease progression. Emerging evidence supports that the malignant T cells take control of the inflammatory environment, suppressing cellular immunity and anti-tumor responses while promoting a chronic inflammatory milieu that fuels their own expansion. Here, we review the inflammatory changes associated with disease progression in CTCL and point to their wider relevance in other cancer contexts. We further define the term "malignant inflammation" as a pro-tumorigenic inflammatory environment orchestrated by the tumor cells and discuss some of the mechanisms driving the development of malignant inflammation in CTCL

Status of alfalfa witches’ broom phytoplasma disease in Iran

Alfalfa witches’ broom (AWB) is one of the most important and destructive diseases of alfalfa in Iran. Based on characteristic disease symptoms and direct and nested polymerase chain reactions, the status of AWB disease was evaluated in different growing areas of Iran. Restriction fragment length polymorphism was used to identify AWB disease associated phytoplasmas. Furthermore, infection rate, disease severity, death rate of infected plant in the summer and winter and overwintering of disease vector were assessed. Based on the results, AWB disease was reported on different alfalfa cultivars in Yazd, Fars, Sistan-Va-Baluchestan, Kerman, Hormozgan, Bushehr, Esfahan, Chaharmahal-Va-Bakthiari, South Khorasan and Khuzestan provinces of Iran. Phytoplasmas associated with AWB in these areas were identified as ‘Candidatus Phytoplasma aurantifolia’, belonging to peanut witches’ broom (16SrII) group. In Abarkooh and Ashkezar (Yazd province) and Bondarooz (Bushehr province) the recorded disease incidence was up to 100%. The highest disease severity was found in Rezvan Shahr (Ashkezar, Yazd province) in 3 years old alfalfa fields. The highest death rate of infected plants in summer and winter were recorded as 26% and 13% in Ashkezar and Abarkooh in Yazd province, respectively. Different nymph stages of the insect vector, Orosius albicinctus, were identified on tamarisk (Tamarix aphylla) and saxaul (Haloxylon persicum and H. aphyllum) in the winter. The highest population ofO. albicinctus, observed on tamarisk plants adjacent to the infected alfalfa fields in Milleshbar (Ardakan, Yazd province), suggested this as a possible source of natural spread of AWB

Status of sesame phyllody and its control methods in Yazd, Iran

Phyllody is one of the most important diseases of sesame in Iran. During 2008-10, to evaluate disease status, a survey was carried out in sesame fields in Yazd province. Occurrence of sesame phyllody was observed in all the sesame growing fields in Yazd, but whole infection of fields was observed in Rezvan Shahr (Ashkezar, Yazd province). On the basis of RFLP analysis sesame phyllody phytoplasma was identified as a member of peanut witches’ broom (16SrII) group. No differences were observed in plant heights of infected and healthy plants. Total seed yield was reduced by 55.07% in infected plants and 1,000 seed weight showed a 21.49% decrease in infected plants. Wrinkled seeds increased in diseased plants up to 56.07%. Results of variance analysis of control methods showed that sowing date and spraying have significant effects on infection. Mean comparison of infection percent with LSD tests showed that delay in sowing date reduced sesame phyllody up to 31%. Spraying with Confidor reduced disease incidence at the first and second sowing date by 18.8 and 7.8% respectively but no differences were observed in yields. Seed treatment with Gaucho has no effect on disease incidence. Collectively, sowing of sesame straight after wheat harvesting in May needed spraying to reduce disease incidence, but delay in the sowing date to July 5 can reduce disease incidence without any significant differences in seed yield. Delay in sowing date is dependent on weather and needs to be determined for each area