Three LNA-based mercaptoacetamido-linked nonionic nucleoside dimers T
L
-S-T, T-S-T
L
, and T
L
-S-T
L
have been synthesized by HOBT and HBTU catalyzed condensation of silyl-protected 2-S-(thymidin-5 ...′-yl)mercaptoacetic acid or 2-S-(2 ′-O,4 ′-C-methylenethymidin-5 ′-yl)mercaptoacetic acid with 3 ′-amino-3 ′-deoxy-5 ′-O-DMT-2 ′-O,4 ′-C-methylenethymidine or with 3 ′-amino-3 ′-deoxy-5 ′-O-DMT-β-thymidine followed by desilylation of the protected dimers. The 3 ′-O-phosphoramidite derivative of one of the nucleoside dimers was successfully prepared by condensation with P(-Cl)(-OCH
2
CH
2
CN)-N(iPr)
2
} in DCM in the presence of N,N-diisopropylethylamine (DIPEA), which is a building block for the preparation of mercaptoacetamido-linked oligonucleotides of therapeutic applications.
This study evaluated face, content, construct validity, and reliability of Thiel embalmed cadavers (TEC) as a training tool for transperitoneal laparoscopic nephrectomy (TLN).
The study participants ...were prospectively recruited through an advanced laparoscopic renal resection teaching skill course. The participants were grouped into: nonexperts (performed fewer than 50 TLNs) and experts (performed more than 50 TLNs). All the participants performed TLN on TEC, which was video recorded. All participants rated their overall experience of performing TLN on TEC with emphasis on realism (face validity). The participants were asked to rate the appropriateness of TEC for training in TLN (content training). Two experienced laparoscopic surgeons, using validated modified Objective Structured Assessment of Technical Skills, assessed the individual videos. The parameters studied were: Respect for tissues, time and motion, and instrument handling for each step of laparoscopic nephrectomy (LN) (construct validity). Test-retest and interrater reliability was also evaluated.
Twenty-four participants (4 experts and 20 nonexperts) took part in this study. The mean overall rating for the experience of TLN on TEC was 4.5 (Face Validity). The mean score for the appropriateness of TEC as a training tool for TLN was 4.6 (content validity) when evaluated by the four experts. The mean scores for the nonexperts and experts using video recordings for various variables were: Respect for tissue-1.74 (standard deviation SD-0.62) vs 3.63 (SD-1.06), (P<0.01), time and motion-1.74 (SD-0.58) vs 4 (SD-0.76), (P<0.01), and instrument handling-1.84 (SD-0.61) vs 4.25 (SD-0.71), (P<0.01) (construct validity). The study also suggested test-retest and interrater reliability.
This study suggests face, content, and constructs validity and reliability of the TEC as a training tool for TLN.
In this study, the structural and magnetodielectric properties of gadolinium (Gd3+) substituted yttrium iron garnet (Y2GdFe5O12) are investigated. The hydrothermal synthesis method is used to prepare ...the powders. The prepared powders are sintered at three different temperatures. X‐ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) are used to characterize the structural and morphological properties of the sintered samples. The dielectric properties are measured over a frequency range of 100 Hz–1 MHz. A vibration sample magnetometer (VSM) is used to determine the magnetic parameters of the samples and it is observed that the magnetic properties of the samples depend on the sintering temperature. The thermal change in magnetization parameter and the transition temperature of the samples are measured using the pulse magnetometer by applying 5kOe magnetic field. The collected results are analyzed and discussed using various theories.
Abstract 2D topological insulators promise novel approaches towards electronic, spintronic, and quantum device applications. This is owing to unique features of their electronic band structure, in ...which bulk-boundary correspondences enforces the existence of 1D spin–momentum locked metallic edge states—both helical and chiral—surrounding an electrically insulating bulk. Forty years since the first discoveries of topological phases in condensed matter, the abstract concept of band topology has sprung into realization with several materials now available in which sizable bulk energy gaps—up to a few hundred meV—promise to enable topology for applications even at room-temperature. Further, the possibility of combining 2D TIs in heterostructures with functional materials such as multiferroics, ferromagnets, and superconductors, vastly extends the range of applicability beyond their intrinsic properties. While 2D TIs remain a unique testbed for questions of fundamental condensed matter physics, proposals seek to control the topologically protected bulk or boundary states electrically, or even induce topological phase transitions to engender switching functionality. Induction of superconducting pairing in 2D TIs strives to realize non-Abelian quasiparticles, promising avenues towards fault-tolerant topological quantum computing. This roadmap aims to present a status update of the field, reviewing recent advances and remaining challenges in theoretical understanding, materials synthesis, physical characterization and, ultimately, device perspectives.
The Essential Surgical Skills Course (ESSC) is a multi-specialty induction "boot camp" style course that has been run successfully for five years. The aim of the current paper is to create an ...accurate guide for the replication of the course by other teams and assess the course's fitness for purpose, through the survey feedback provided by trainees.
The course's fitness for purpose was assessed through cumulative five-year survey feedback from trainees. This observational study describes the design and process of content adjustment according to feedback.
The course its five-year span offered twelve different procedural skills in four different specialties. Feedback for each session was persistently >8/10. Key themes identified as beneficial include teacher-to-trainee ratio (often 1:1), teaching style, course structure and responsiveness.
The ESSC was found to be fit for purpose for the induction of trainees into surgical training. The key factors contributing to the success of the course include the structured method of curriculum design, outstanding teaching delivery methods, teacher-to-trainee ratio, the availability of appropriate faculty and infrastructure and the willingness to learn from trainee feedback and adjust the content of the course accordingly. It acts as a paradigm for courses aimed to prepare surgical trainees for a "step-up" in their careers.
In this present study, Li
2
O–Al
2
O
3
–B
2
O
3
glass matrix doped with a small percentage of TiO
2
(ranging from 0 to 1 mol%) was prepared and characterized by X-Ray Diffraction (XRD), FTIR and ...Differential Scanning Calorimetric (DSC) techniques. After that, Optical Absorption (OA), Photo Luminescence (PL), Electron Paramagnetic Resonance (EPR) and Second Harmonic Generation (SHG) have been performed as a function of TiO
2
concentration. The outcome of these studies spelled out different oxidation states of Ti ions. However, sample containing up to about 0.8 mol% of the TiO
2
, mostly will be in the state of Ti
4+
with substitutional octahedral arrangement in the glass chain and is responsible for PL. Beyond this percentage, it is noticed that some parts of Ti ions reduced Ti
4+
to Ti
3+
state. The results of Photo-Induced Second Harmonic Generation (PSHG) together with other spectroscopic studies were discussed for all chosen samples and indicated that the Photo-Induced Birefringence (PIB) of sample with 0.8 mol% TiO
2
is the most suitable for NLO (non-linear optics) devices.
We report optical transmission measurements through a single crystal of the Weyl semimetal TaAs at terahertz frequencies. The measurements were performed at T=1.6 K using intense coherent light from ...a free-electron laser in high magnetic fields. We detected small but measurable changes in the sample’s transparency upon applying dc voltage (current) to the sample. In a constant magnetic field, the sign of the transmission change depends on the current direction. The effect disappears in zero magnetic field. These observations are qualitatively consistent with theory predictions for optical signatures of the chiral anomaly in a Weyl semimetal.
► Ninety-four traditional Indian medicinal herbs have been reviewed for carbohydrates. ► Fructans, Mannans, Arabinogalactans and xylans as immunomodulators in herbs. ► Antitumor properties and role ...of plant carbohydrates are assessed. ► Prognosis for medical application of polysaccharides from Rasayana plants. ► Carbohydrates play major role in bringing physiological homeostasis.
Rasayana constitutes a very important class of Ayurvedic herbs, which acts as rejuvenators and tonic. Despite intensive research on evaluating the medicinal basis for the purported medical benefits of Rasayana herbs, still a specific chemical guiding principle for the characterization of these herbs in one single category is unclear. Here we explore the possibility that polysaccharides play a key role in Rasayana properties exhibited by medicinal plants. Further on this could be a possible field for exploration for a common factor present in some of the Ayurvedic herbs. The present review covers a literature spanning from 1956 to 2011. Some translations of traditional Ayurvedic texts dating back to the first century AD have been referred to as well. In our assessment of the present literature and studies carried out it is presupposed that the presence of benevolent plant polysaccharides must be one of the important features symbolizing a common effectiveness in most of the Ayurvedic Rasayana herbs. Of the many plant metabolites polysaccharides have not so far been considered and studied effectively compared to other secondary metabolites like saponins, alkaloids, etc. Although all the results reported until now suggest a major contribution of polysaccharide towards the maintenance of physiological homeostasis, which is the guiding principle of Rasayana therapy. The present review is an attempt to find a connective link between the concept of Rasayana and well-being; and the role of plant polysaccharides. Lack of clinical information on number of polysaccharides showing promise is a limiting factor for a complete understanding. It is also important to carry out a molecular interaction study to understand the behavior of polysaccharides discussed in the present review.
Cementitious structures exhibit high compression strength but suffer from inherent brittleness. Conversely, nature creates structures using mostly brittle phases that overcome the strength-toughness ...trade-off, mainly through internalized packaging of brittle phases with soft organic binders. Here, we develop complex architectures of cementitious materials using an inverse replica approach where a soft polymer phase emerges as an external conformal coating. Architected polymer templates are printed, cement pastes are molded into these templates, and cementitious structures with thin polymer surface coating are achieved after the solubilization of sacrificial templates. These polymer-coated architected cementitious structures display unusual mechanical behavior with considerably higher toughness compared to conventional non-porous structures. They resist catastrophic failure through delayed damage propagation. Most interestingly, the architected structures show significant deformation recovery after releasing quasi-static loading, atypical in conventional cementitious structures. This approach allows a simple strategy to build more deformation resilient cementitious structures than their traditional counterparts.
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•A polymer-coated architected cementitious structure is developed•Catastrophic failure is prevented through delayed damage propagation mechanisms•Significant structural recovery is observed after releasing compression loading
Mechanical property; materials structure; materials mechanics
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