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Bread wheat varieties as influenced by different nitrogen levels 总被引:2,自引:2,他引:2
INTRODUCTION Dera Ismail Khan lies in Pakistan’s arid zone (71.07° longitude, 31.57° latitude and 500 m above sea level). This zone is in the extreme south of (NWFP) Pakistan at the bank of the River Indus. Dera Ismail Khan is bounded by Sulaiman Range to the West, the Indus River on the East, Marwat and Bhit- tani Ranges on the North and Vehowa Nala (Punjab) on the South. Besides certain local variability the area is comprised of four basic divisions viz mountains, a series … 相似文献
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This study examines impact of the educational use of Facebook group on the high school students’ proper usage of language. The study included thirty students who attend 11th grade in a high school in Trabzon, Turkey. Firstly, preliminary data about Facebook usage of students were obtained to understand the factors that motivate students to use Facebook and whether they use them for the educational purpose or not. Then, a Facebook group was created, in which a literature teacher was assigned as the guide of the group. This study lasted twelve weeks. The students’ assignments such as compositions, poems, and vignettes, discussions, the teacher’s views and observation, data from the interviews with participants were analyzed in this study. Results from this study indicated that that Facebook group was effective on issues such as development of writing abilities of students, communication and cooperation between teacher and students, and cooperation and communication among students. The original idea for this research was to determine that proper usage of language can be improved in social context if Facebook group is created as a flexible online community with interactive and reflective activities, effective tool of sharing and communication. This study demonstrates how Facebook can successfully be used in educational environment appropriately. 相似文献
85.
Nadeem Hera Malan Pieter Khan Amir Asif Mohd Ahmad Siddiqui Mansoor Tuhafeni Angombe Simon Ahmad Faheem 《Journal of Zhejiang University. Science. B》2021,22(7):563-574
This study focused, for the first time, on the effect of ultrasonic features on the extraction efficiency of secondary metabolites in mustard seed cake(MSC). The nematostatic potential of sonicated seed cake was examined against the second-stage juveniles(J2 s) of root-knot nematode, Meloidogyne javanica. The results show that a 35 ppm(parts per million) concentration of a sonicated extract(SE) sample of MSC caused 65% J2 s mortality at 18 h exposure period in vitro. It also significantly suppressed the root-knot index(RKI=0.94) in tomato roots. The lethal concentration values for SE were 51.76, 29.79, and 13.34 ppm,respectively, at 6, 12, and 18 h of the exposure period, and the lethal concentration values for the non-sonicated extract(NSE)sample were 116.95, 76.38, and 55.59 ppm, respectively, at similar exposure time. Sinapine and gluconapin were identified as the major compounds in ultrasonic-assisted MSC. Because of the high extraction efficiency of metabolites in the SE, all treatments of SE were shown to be antagonistic to J2 s. Thus, this study of ultrasonication activity-based profiling of MSC may help generate target-based compounds at a scale relevant to the control of disease caused by nematodes in economic crops. 相似文献
86.
Justine E. Hoch Ori Ossmy Whitney G. Cole Shohan Hasan Karen E. Adolph 《Child development》2021,92(4):1337-1353
Pre-mobile infants and caregivers spontaneously engage in a sequence of contingent facial expressions and vocalizations that researchers have referred to as a social “dance.” Does this dance continue when both partners are free to move across the floor? Locomotor synchrony was assessed in 13- to 19-month-old infant–mother dyads (N = 30) by tracking each partner’s step-to-step location during free play. Although infants moved more than mothers, dyads spontaneously synchronized their locomotor activity. For 27 dyads, the spatiotemporal path of one partner uniquely identified the path of the other. Clustering analyses revealed two patterns of synchrony (mother-follow and yo-yo), and infants were more likely than mothers to lead the dance. Like face-to-face synchrony, locomotor synchrony scaffolds infants’ interactions with the outside world. 相似文献
87.
Theodor Schwann, the German physiologist who first propounded the cell theory with M Schieiden, had diverse interests. He
was not only the first to isolate the enzyme pepsin, but also investigated muscle contraction and nerve structure. In the
mid nineteenth century Schwann discovered that a sheath made up of myelin covered the axons of neurons in the peripheral nervous
system (PNS). The cells that form the myelin are today called Schwann cells after him. Today, we know that the Schwann cells
not only form the myelin sheath around neurons, but also regulate several neuronal functions and are an indispensable part
of the PNS. 相似文献
88.
Brain type natriuretic peptide (BNP)—A marker of new millennium in diagnosis of congestive heart failure 总被引:1,自引:0,他引:1
Arun Raizada Suman Bhandari Muzaiyan Ahmed Khan Harsh Vardhan Singh Sherin Thomas Vikram Sarabhai Neelima Singh Naresh Trehan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):4-9
The burden of disease in patients with congestive heart failure is high. The future of BNP looks promising as it may be a
better diagnostic tool for the diagnosis of CHF in developing countries in new millennium. Natriuretic peptide hormones, a
family of vasoactive peptides with many favourable physiological properties, have emerged as important contenders for development
of diagnostic tools and therapeutic agents in cardiovascular disease. Measurement of B-type natriuretic peptide has become
as an easy-to-perform bedside test. The clinical and diagnostic significance of the measurement of plasma Nt-proBNP in the
diseases of the cardiovascular system with particular emphasis on the assessment of patients with heart failure and their
effects on predicting survival rate. The plasma levels of Nt-proBrain Natriuretic peptide responds more vigorously after myocardial
infarction than those of other natriuretic peptides. This article is an attempt to give a short overview on the utility of
BNP-blood levels for the diagnosis and treatment of heart failure 相似文献
89.
S. Khan 《Educational technology research and development : ETR & D》2008,56(4):423-447
This research assessed the value of case study methodology in the design of an educational computer simulation. Three sources
of knowledge were compared to assess the value of case study: practitioner and programmer knowledge, disciplinary knowledge,
and knowledge obtained from a case study of teacher practice. A retrospective analysis revealed that the case study was the
source of 16 out of 23 design decisions and therefore was the most significant influence on the design of the simulation.
The case study was particularly effective in sensitizing the design team to the classroom context, identifying common and
uncommon teacher practices, revealing unexpected dimensions of interactions in the classroom, and generating constructive
changes to the design of the simulation. Case studies can significantly enrich the design of educational software and are
a promising methodological choice for design teams.
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S. KhanEmail: |
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