Comparative study of thulium fiber laser versus holmium:yttrium-aluminum-garnet laser for ureteric stone management with semi-rigid ureteroscopy: A prospective, single-center study

Objective:To compare the efficacy and safety of thulium fiber laser(TFL)and holmium:yttrium-aluminum-garnet(Ho:YAG)laser for ureteric stone management with semi-rigid ureteroscopy.Methods:In a prospective study from January 2020 to December 2021,we compared 40 patients in each group who underwent semi-rigid ureteroscopic lithotripsy with TFL and that with Ho:YAG laser.Stone volume,stone density,stone fragmentation rates,total lasing time,total operative time,endoscopic vision,retropulsion and stone free rates were analyzed in both groups and compared.Results:Mean stone volume was comparable in the TFL group and the Ho:YAG laser group(282.45[standard deviation,SD 139.79]mm3 vs.279.49[SD 312.52]mm3;p=0.964).Mean stone density was also comparable in the TFL group and the Ho:YAG laser group(1135.30[SD 317.04]Hounsfield unit vs.1131.75[SD 283.03]Hounsfield unit;p=0.959).The mean stone fragmentation rates calculated as stone volume divided by lasing time were 25.85(SD 10.61)mm3/min and 21.37(SD 14.13)mm3/min in the TFL group and the Ho:YAG laser group,respectively(p=0.113).The mean total lasing time(10.15[SD]4.69 min vs.11.43[SD 4.56]min;p=0.222),mean operative time(25.13[SD 9.51]min vs.25.54[SD 10.32]min;p=0.866),and mean total hospital stay(2.62[SD 0.77]days vs.2.61[SD 0.84]days;p=0.893)were comparable in the TFL group and in the Ho:YAG group.The vision was better and retropulsion was less in the TFL group.The stone-free rate at 1 month postoperatively was slightly better in the TFL group(100%vs.90%;p=0.095).

Pharmacognostic evaluation of Cayratia trifolia (Linn.)leaf

Objective:To present a detailed pharmacognostic study of the leaf of Cayratia trifolia(C.trifolia)Linn.(Vitaceae),an important plant in the Indian system of medicine.Methods:The macroscopy,microscopy,physiochemical analysis,preliminary testing,fluorescence analysis of powder of the plant and other WHO recommended methods for standardization were investigated.Results:Leaves are trifoliolated with petioles(2-3 cm)long.Leaflets are ovate to oblong-ovate,(2-8 cm)long,(1.5-5 cm)wide,pointed at the tip.The leaf surface shows the anisocytic type stomata covered with guard cells followed by epidermis layer.Leaf surface contents including veins.vein islet and vein termination were also determined.Transverse section of leaf shows the epidermis layer followed by cuticle layer and vascular bandies(xylem and phloem).The mesophyll is differentiated into palisade and spongy parenchyma.Abundant covering trichomes emerge from the upper epidermis.Trichomes are uniseriate and multicellular.Strips of collenchyma are present below and upper layer of epidermis.Conclusions:It can be concluded that the pharmacognostic profile of the C.trifolia is helpful in developing standards for quality,purity and sample identification.

On the mechanistic origins of maximum strength in nanocrystalline metals

The maximum strength of polycrystalline metals/alloys has been suggested to occur at nanoscale grain sizes where the governing deformation mechanism transitions from dislocation plasticity to grain boundary mediated deformation.Despite tremendous progress recently uncovering links between transitions in nanoscale mechanisms and peak strength,the scientific literature is mostly devoid of any quantitative support,owing to the difficulty in measuring the resolved contribution of individual mechanisms to microstructural strain accommodation.In this study,the contribution of individual nanoscale mechanisms to the overall deformation of nanocrystalline Ni is calculated from atomistic simulations leveraging continuum-based kinematic metrics to compute mechanistic contributions to microstructural strain.