PERENCANAAN KEBUTUHAN MATERIAL (PKM) PADA PRODUKSI KINCIR ANGIN KAPASITAS 100 WATT

Banda Ace

Local Suppression of T Cell Responses by Arginase-Induced L-Arginine Depletion in Nonhealing Leishmaniasis

The balance between T helper (Th) 1 and Th2 cell responses is a major determinant of the outcome of experimental leishmaniasis, but polarized Th1 or Th2 responses are not sufficient to account for healing or nonhealing. Here we show that high arginase activity, a hallmark of nonhealing disease, is primarily expressed locally at the site of pathology. The high arginase activity causes local depletion of L-arginine, which impairs the capacity of T cells in the lesion to proliferate and to produce interferon-γ, while T cells in the local draining lymph nodes respond normally. Healing, induced by chemotherapy, resulted in control of arginase activity and reversal of local immunosuppression. Moreover, competitive inhibition of arginase as well as supplementation with L-arginine restored T cell effector functions and reduced pathology and parasite growth at the site of lesions. These results demonstrate that in nonhealing leishmaniasis, arginase-induced L-arginine depletion results in impaired T cell responses. Our results identify a novel mechanism in leishmaniasis that contributes to the failure to heal persistent lesions and suggest new approaches to therapy

Attunement to haptic information helps skilled performers select implements for striking a ball in cricket

This study examined the perceptual attunement of relatively skilled individuals to the physical properties of striking implements in the sport of cricket. We also sought to assess whether utilizing bats with different physical properties would influence performance of a specific striking action: the front foot straight drive. Eleven skilled male cricketers (mean age = 16.6 ± 0.3 years) from an elite school cricket development program consented to participate in the study. While blindfolded, participants wielded six bats exhibiting different mass and moment of inertia (MOI) characteristics and were asked to identify the three bats they preferred the most for hitting a ball to a maximum distance by performing a front foot straight drive (a common shot in cricket). Next, participants actually attempted to hit balls projected from a ball machine using each of the six bat configurations to enable kinematic analysis of front foot straight drive performance with each implement. Results revealed that, on first choice, the two bats with the smallest mass and MOI values (1 and 2) were most preferred by almost two thirds (63.7 %) of the participants. Kinematic analysis of movement patterns revealed that bat velocity, step length, and bat-ball contact position measures significantly differed between bats. Data revealed how skilled youth cricketers were attuned to the different bat characteristics and harnessed movement system degeneracy to perform this complex interceptive action