95 research outputs found
Morphology and seed protein profile for a new species of the genus Cleome L. (Cleomaceae) from Pakistan
A new species of the genus Cleome L. from Pakistan is described and illustrated. The new species is described under the name C. karachiensis sp. nov. and compared with two closely related species i.e., Cleome brachycarpa and C. viscosa in terms of morphology, palynology, seed morphology and seed protein profile. A key to the species of genus Cleome L. from Pakistan is also provided
Heat induction in two-dimensional grapheneâFe3O4 nanohybrids for magnetic hyperthermia applications with artificial neural network modeling
We report the synthesis and characterization of graphene functionalized with iron (Fe3+) oxide (G-Fe3O4) nanohybrids for radio-frequency magnetic hyperthermia application. We adopted the wet chemical procedure, using various contents of Fe3O4 (magnetite) from 0â100% for making two-dimensional grapheneâFe3O4 nanohybrids. The homogeneous dispersal of Fe3O4 nanoparticles decorated on the graphene surface combined with their biocompatibility and high thermal conductivity make them an excellent material for magnetic hyperthermia. The morphological and magnetic properties of the nanohybrids were studied using scanning electron microscopy (SEM) and a vibrating sample magnetometer (VSM), respectively. The smart magnetic platforms were exposed to an alternating current (AC) magnetic field of 633 kHz and of strength 9.1 mT for studying their hyperthermic performance. The localized antitumor effects were investigated with artificial neural network modeling. A neural net time-series model was developed for the assessment of the best nanohybrid composition to serve the purpose with an accuracy close to 100%. Six Nonlinear Autoregressive with External Input (NARX) models were obtained, one for each of the components. The assessment of the accuracy of the predicted results has been done on the basis of Mean Squared Error (MSE). The highest Mean Squared Error value was obtained for the nanohybrid containing 45% magnetite and 55% graphene (F45G55) in the training phase i.e., 0.44703, which is where the model achieved optimal results after 71 epochs. The F45G55 nanohybrid was found to be the best for hyperthermia applications in low dosage with the highest specific absorption rate (SAR) and mean squared error values
EFFECT OF SUPPLEMENTAL IRRIGATION ON WHEAT WATER PRODUCTIVITY UNDER RAINFED ECOLOGY OF POTHOHAR, PAKISTAN
For rainfed ecology, water is the most limiting natural resource and its effective utilization is indispensable in order to optimize crop water productivity. A field study on wheat crop was carried out to asses the impact of different irrigation depths through sprinkler irrigation system at three phonological stages viz. tilleing, anthesis and grain filling. Randomized Complete Block Design (RCBD) was used in the trail and had three repeats. ĂÂ The area under study received 195 mm seasonal rainfall. Supplemental irrigation depths at three phonological stages, using small quantities of water through sprinkler irrigation system, significantly promoted the crop growth. The irrigation depth 25 mm gave the maximum output for biological yield (6504 ), grain yield (2030 ), thousand grain weight (28), plant height (87 ) and spike length (10 ). The highest water productivity of 0.97 kg/m3 was achieved with 25 mm supplemental irrigation depth when applied at tillering and anthesis stages
Strengthening Food Security in Pakistan During the Covid-19 Pandemic
Pakistan is facing numerous socioeconomic impacts of the Covid-19 pandemic, including on food security. Food insecurity, which is a long-standing issue, has become more visible since the pandemic. Covid-19 Responses for Equity (CORE) partner the Sustainable Development Policy Institute (SDPI) â a leading policy research thinktank â has been supporting the Government of Pakistan to maintain essential economic activity and protect workers and small producers during the pandemic. One notable contribution has been the development of a Food Security Portal, which is being used by the government to better manage food security in the country. It is the first track and trace system from farm to fork for essential food items
Recommended from our members
Novel acridine-based thiosemicarbazones as âturn-on' chemosensors for selective recognition of fluoride anion: a spectroscopic and theoretical study
New thiosemicarbazide-linked acridines 3aâc were prepared and investigated as chemosensors for the detection of biologically and environmentally important anions. The compounds 3aâc were found selective for fluoride (Fâ) with no affinity for other anions, i.e. âOAc, Brâ, Iâ, HSO4â, SO42â, PO43â, ClO3â, ClO4â, CNâ and SCNâ. Further, upon the gradual addition of a fluoride anion (Fâ) source (tetrabutylammonium fluoride), a well-defined change in colour of the solution of probes 3aâc was observed. The anion-sensing process was studied in detail via UVâvisible absorption, fluorescence and 1H-NMR experiments. Moreover, during the synthesis of acridine probes 3aâc nickel fluoride (NiF2), a rarely explored transition metal fluoride salt, was used as the catalyst. Theoretical studies via density functional theory were also carried out to further investigate the sensing and anion (Fâ) selectivity pattern of these probes
Untypeable hepatitis C virus subtypes in Pakistan: A neglected section
Diagnostically untypeable subtypes contribute a considerable percent of hepatitis C virus (HCV) subtypes in Pakistan. In the present study, chronically infected HCV patients with known viremia were subjected to HCV genotyping. Among the total retrieved samples, 92.7% (64/69) were found typeable while 7.24% (5/69) were diagnostically untypeable. In conclusion, the presence of large number of untypeable HCV subtypes emphasizes the need of an updated type-specific genotyping assay and consideration of primers for proportionally rare subtypes to minimize the number of untypeable HCV subtypes
Charge Crowding in Graphene-Silicon Diodes
The performance of nanoscale electronic devices based on a two-three
dimensional (2D-3D) interface is significantly affected by the electrical
contacts that interconnect these materials with external circuitry. This work
investigates charge transport effects at the 2D-3D ohmic contact coupled with
the thermionic injection model for graphene/Si Schottky junction. Here, w e
focus on the intrinsic properties of graphene-metal contacts, paying particular
attention to the nature of the contact failure mechanism under high electrical
stress. According to our findings, severe current crowding (CC) effects in
highly conductive electrical contact significantly affect device failure that
can be reduced by spatially varying the contact properties and geometry. The
impact of electrical breakdown on material degradation is systematically
analyzed by atomic force, Raman, scanning electron, and energy dispersive X-ray
spectroscopies. Our devices withstand high electrostatic discharge spikes over
a longer period, manifesting high robustness and operational stability. This
research paves the way towards a highly robust and reliable graphene/Si
heterostructure in futuristic on-chip integration in dynamic switching. The
methods we employed here can be extended for other nanoscale electronic devices
based on 2D-3D interface
- âŠ