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This chapter describes the phenomenon of Raman scattering from the point of view of classical electrodynamics and quantum mechanics. Raman scattering is a type of inelastic scattering of light by molecules that changes the energy of a photon by the energy equal to a vibrational transition of that molecule. The symmetry of vibrational modes and the activity of vibrational modes in Raman spectra is discussed via group theory for molecules and minerals. The chapter describes how the information gleaned from Raman spectra can be used to identify structural information about a given sample and how this information can be useful to Earth and planetary scientists. The principal components of laboratory and remote Raman instrumentation are defined, including excitation sources, spectrographs, and detectors, and the ways in which recent advances in technology have facilitated the application of Raman spectroscopy for Earth and planetary science are discussed. Some technological advances include the development of reliable continuous wave (CW) and pulsed lasers at a variety of wavelengths, the advancement of multichannel detectors such as two-dimensional charge-coupled devices and photodiode arrays, and the coupling of optical accessories such as microscopes and telescopes. The applications of these advanced Raman systems in the fields of Earth and planetary science are highlighted.
To assess the effect of tranexamic acid in head and neck surgical procedures.
A prospective, double-blind and randomised, parallel group, placebo-controlled clinical trial was conducted. Ninety-two patients undergoing various head and neck surgical procedures were randomised. Subjects received seven infusions of coded drugs (tranexamic acid or normal saline) starting at the time of skin closure. Haematological, biochemical, blood loss and other parameters were observed by the staff, who were blinded to patients’ group allocation (case or control).
Patients were analysed on the basis of type of surgery. Fifty patients who had undergone surgical procedures, including total thyroidectomy, total parotidectomy, and various neck dissections with or without primary tumour excision, were included in the first group. The second group comprised 41 patients who had undergone hemithyroidectomy, lobectomy or superficial parotidectomy. There was no statistical difference in blood parameters between both groups. There was a reduction in post-operative drain volume, but this was not significant.
Although this prospective, randomised, placebo-controlled clinical trial found a reduction in post-operative drain volume in tranexamic acid groups, the difference was not statistically significant between the various head and neck surgical procedure groups.
The design of high energy Li-ion batteries (LIBs) by coupling high voltage LiNi0.5Mn1.5O4 (LNMO) cathode and Li4Ti5O12 (LTO) anode ensures effective and safe energy-storage. LTO–LNMO full-cells (FCs) with difference in electrode grain sizes and presence of excess Mn3+ in cathode were studied using micron-sized commercial LTO, nanostructured LTO donuts (LTOd), P4332 LNMO nanopowders, and nanostructured Fd3m LNMO caterpillars (LNMOcplr). Among the studied FCs, LTOd–LNMOcplr was detected with a stable capacity of 69 mA h/g (1C rate), 99% coulombic efficiency, and 87% capacity retention under 200 cycles of continuous charge–discharge studies. The superior electrochemical performance observed in LTOd–LNMOcplr FC was due to the low charge transfer resistance, which is corroborated to the effect of grain sizes and the longer retention of Mn3+ in the electrodes. An effective and simple FC design incorporating both nanostructuring and in situ conductivity in electrode materials would aid in developing future high-performance LIBs.
To study 2D and 3D dosimetric values for bladder and rectum, and the influence of bladder volume on bladder dose in high dose rate (HDR) intracavitary brachytherapy (ICBT). The large patient data incorporated in this study would better represent the inherent variations in many parameters affecting dosimetry in HDR-ICBT.
Material and Methods:
We prospectively collected data for 103 consecutive cervical cancer patients (over 310 HDR fractions) undergoing CT-based HDR-ICBT at our centre. Correlation among bladder and rectum maximum volume doses and corresponding International Commission on Radiation Units and Measurement (ICRU) point doses were estimated and analysed. Impact of bladder volume on bladder maximum dose was assessed.
The ICRU point doses to bladder and rectum varied from the volumetric doses to these organs. Further, bladder volume poorly correlated with bladder maximum dose for volume variations encountered in the clinical practice at our centre.
ICRU point doses to bladder and rectum are less likely to correlate with long-term toxicities to these organs. Further, in clinical practice where inter-fraction bladder volume does not vary widely there is no correlation between bladder volume and bladder dose.
GaN films have been grown on SiC substrates with an AlN nucleation layer by using a metal organic chemical vapor deposition technique. Micro-cracking of the GaN films has been observed in some of the grown samples. In order to investigate the micro-cracking and microstructure, the samples have been studied using various characterization techniques such as optical microscopy, atomic force microscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy (TEM). The surface morphology of the AlN nucleation layer is related to the stress evolution in subsequent overgrown GaN epilayers. It is determined via TEM evidence that, if the AlN nucleation layer has a rough surface morphology, this leads to tensile stresses in the GaN films, which finally results in cracking. Raman spectroscopy results also suggest this, by showing the existence of considerable tensile residual stress in the AlN nucleation layer. Based on these various observations and results, conclusions or propositions relating to the microstructure are presented.
In this paper, we present and implement a novel approach for position-based visual servoing. The challenge of controlling the mobile robot while simultaneously estimating the camera to mobile robot transformation is solved. This is achieved using gradient descent (GD)-based estimation and the sliding-mode approach. The GD approach allows online parameter estimation for controlling the robot to achieve a desired position and orientation. The adaptive nature of the parameters demonstrates the robustness of the system. In contrast to existing work, the proposed technique achieves both estimation and control tasks in a single experiment. Simulation and experimental results are provided to validate the performance of the proposed scheme.
The evidence base for the use of ECT in children and adolescents aged under 18 years (hereafter referred to as ‘paediatric ECT’) consists of individual case reports, case series and retrospective chart reviews, but no Randomised Controlled Trials (RCTs). This limited evidence base alongside concerns about the effects of ECT on the developing brain may help explain the infrequent use of ECT by child and adolescent psychiatrists. This chapter provides a summary of the issues and considerations pertaining to use of paediatric ECT within the British Isles (United Kingdom and Republic of Ireland). Although legal aspects relating to ECT are covered in Chapter 28, some reference specific to paediatric use is made here.
Biochar has received attention due to its potential for mitigating climate change through carbon sequestration in soil and improving soil quality and crop productivity. This study evaluated the effects of rice straw biochar (RSB) and rice husk ash (RHA) each applied at 5 Mg ha−1 and four N levels (0, 40, 80, and 120 kg ha−1) on soil fertility, growth, and yield of rice and wheat for three consecutive rice–wheat rotations. RSB significantly increased electrical conductivity, dehydrogenase activity, and P and K contents when compared to control (no amendment) up to 7.5 cm soil depth. Both RSB and RHA did not influence shoot N concentration in wheat plant but significantly increased P and K concentrations at 60 days after sowing. Grain yields of both rice and wheat were significantly higher in RSB as compared to control (no amendment) and RHA treatments. While the highest grain yields of rice and wheat were observed at 120 kg N ha−1 in RHA and no biochar-treated plots, a significant increase in grain yields was observed at 80 kg N ha−1 in RSB treatment, thereby saving 40 kg N ha−1 in each crop. Both agronomic and recovery N efficiencies in rice and wheat were significantly higher in RSB-amended soil compared to control. Significant positive correlations were observed between soil N, P, and K concentrations and total N, P, and K concentrations in aboveground biomass of wheat at 60 days after sowing. This study showed the potential benefits of applying RSB for improving soil fertility and yields of rice and wheat in a rice–wheat system.
Background: Biallelic variants in POLR1C are associated with POLR3-related leukodystrophy (POLR3-HLD), or 4H leukodystrophy (Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism), and Treacher Collins syndrome (TCS). The clinical spectrum of POLR3-HLD caused by variants in this gene has not been described. Methods: A cross-sectional observational study involving 25 centers worldwide was conducted between 2016 and 2018. The clinical, radiologic and molecular features of 23 unreported and previously reported cases of POLR3-HLD caused by POLR1C variants were reviewed. Results: Most participants presented between birth and age 6 years with motor difficulties. Neurological deterioration was seen during childhood, suggesting a more severe phenotype than previously described. The dental, ocular and endocrine features often seen in POLR3-HLD were not invariably present. Five patients (22%) had a combination of hypomyelinating leukodystrophy and abnormal craniofacial development, including one individual with clear TCS features. Several cases did not exhibit all the typical radiologic characteristics of POLR3-HLD. A total of 29 different pathogenic variants in POLR1C were identified, including 13 new disease-causing variants. Conclusions: Based on the largest cohort of patients to date, these results suggest novel characteristics of POLR1C-related disorder, with a spectrum of clinical involvement characterized by hypomyelinating leukodystrophy with or without abnormal craniofacial development reminiscent of TCS.
The difference in the defect structures produced by different ion masses in a tungsten lattice is investigated using 80 MeV Au7+ ions and 10 MeV B3+ ions. The details of the defects produced by ions in recrystallized tungsten foil samples are studied using transmission electron microscopy. Dislocations of type b = 1/2 and  were observed in the analysis. While highly energetic gold ion produced small clusters of defects with very few dislocation lines, boron has produced large and sparse clusters with numerous dislocation lines. The difference in the defect structures could be due to the difference in separation between primary knock-on atoms produced by gold and boron ions.
Introduction: Individualizing risk for stroke following a transient ischemic attack (TIA) is a topic of intense research, as existing scores are context-dependent or have not been well validated. The Canadian TIA Score stratifies risk of subsequent stroke into low, moderate and high risk. Our objective was to prospectively validate the Canadian TIA Score in a new cohort of emergency department (ED) patients. Methods: We conducted a prospective cohort study in 14 Canadian EDs over 4 years. We enrolled consecutive adult patients with an ED visit for TIA or nondisabling stroke. Treating physicians recorded standardized clinical variables onto data collection forms. Given the ability of prompt emergency carotid endarterectomy (CEA) to prevent stroke (NNT = 3) in high risk patients, our primary outcome was the composite of subsequent stroke or CEA ≤7 days. We conducted telephone follow-up using the validated Questionnaire for Verifying Stroke Free Status at 7 and 90 days. Outcomes were adjudicated by panels of 3 local stroke experts, blinded to the index ED data collection form. Based on prior work, we estimated a sample size of 5,004 patients including 93 subsequent strokes, would yield 95% confidence bands of +/− 10% for sensitivity and likelihood ratio (LR). Our analyses assessed interval LRs (iLR) with 95% CIs. Results: We prospectively enrolled 7,569 patients with mean 68.4 +/−14.7 years and 52.4% female, of whom 107 (1.4%) had a subsequent stroke and 74 (1.0%) CEA ≤7 days (total outcomes = 181). We enrolled 81.2% of eligible patients; missed patients were similar to enrolled. The Canadian TIA Score stratified the stroke/CEA ≤7days risk as: Low (probability <0.2%, iLR 0.20 [95%CI 0.091-0.44]; Moderate (probability 1.3%, iLR 0.79 [0.68-0.92]; High (probability 2.6%, iLR 2.2 [1.9-2.6]. Sensitivity analysis for just stroke ≤7 days yielded similar results: Low iLR 0.17 [95%CI 0.056-0.52], Medium iLR 0.89 [0.75-1.1], High iLR 2.0 [1.6-2.4]. Conclusion: The Canadian TIA Score accurately identifies TIA patients risk for stroke/CEA ≤7 days. Patients classified as low risk can be safely discharged following a careful ED assessment with elective follow-up. Patients at moderate risk can undergo additional testing in the ED, have antithrombotic therapy optimized, and be offered early stroke specialist follow-up. Patients at high risk should in most cases be fully investigated and managed ideally in consultation with a stroke specialist during their index ED visit.
Dicationic cobalt(II) complexes of the type [Co(fterpy)2]c(X)2·nH2O·mCH3OH (fterpy = 4′-(2-furyl)-2,2′:6′,2″-terpyridine; 1: X = PF6-, n = 1.5, m = 0; 2: X = ClO4-, n = 1, m = 1) have been isolated using self-assembly method and characterized by various spectroscopic techniques. In crystalline states both compounds exhibit gradual and incomplete spin crossover (SCO) behaviour in the temperature range 2-320 K. Various spin states of cobalt(II) in 1 have been confirmed by crystallographic evidences at 150 K and 293 K. A variation in counter anions and solvent molecules from 1 to 2 substantially improves the cooperativity among the spin active metal centres and thereby changing the nature of SCO behaviour.
Nanoemulsion formulation of vitamin D3 have been shown to have better bioavailability than the coarse emulsion preparation in vitro and in vivo animal studies. In the absence of randomised trial in humans, comparing the efficacy of nanotechnology-based miscellised vitamin D3 over conventional vitamin D3, we undertook this study. A total of 180 healthy adults were randomised to receive either micellised (DePura, group A) or conventional vitamin D3 (Calcirol, group B) at a monthly dose of 60 000 IU (1500μg) for 6 months. The outcome parameters were serum 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH), Ca, phosphate, alkaline phosphatase and urinary Ca:creatinine ratio. A total of eighty-nine subjects in group A and seventy-seven in group B completed the trial. Subjects in both the groups had a significant increase in their serum 25(OH)D levels following supplementation (group A: 21·5 (sd 10·9) to 76·7 (sd 18·8) nmol/l (P<0·001); group B: 22·8 (sd 10·4) to 57·8 (sd 16·0) nmol/l (P<0·001)). Participants in micellised group had an additional increase of 20·2 (95 % CI 14·0, 26·4) nmol/l in serum 25(OH)D levels (P<0·001). The difference between the groups was 17·5 (95 % CI 11·8, 23·1) nmol/l, which remained statistically significant (P<0·001) even after adjustment for age and sex. Significant decline in mean serum PTH was observed in both the groups. No hypercalcaemia or hypercalciuria was noted. Although supplementation with both the preparations resulted in a significant rise in serum 25(OH)D levels, micellised vitamin D3 appeared to be more efficacious in achieving higher levels of serum 25(OH)D.
A novel series of nanocrystalline AlCuCrFeMnWx (x = 0, 0.05, 0.1, 0.5) high-entropy alloys (HEAs) were synthesized by mechanical alloying followed by spark plasma sintering. The phase evolution of the current HEAs was studied using X-ray diffraction (XRD), transmission electron microscopy, and selected area electron diffraction. The XRD of the AlCuCrFeMn sintered HEA shows evolution of ordered B2 phase (AlFe type), sigma phase (Cr rich), and FeMn phase. AlCuCrFeMnWx (x = 0.05, 0.1, 0.5 mol) shows formation of ordered B2 phases, sigma phases, FeMn phases, and BCC phases. Micro-hardness of the AlCuCrFeMnWx samples was measured by Vickers microindentation and the maximum value observed is 780 ± 12 HV. As the tungsten content increases, the fracture strength under compression increases from 1010 to 1510 MPa. Thermodynamic parameters of present alloys confirm the crystalline phase formation, and finally structure–property relationship was proposed by conventional strengthening mechanisms.
The behavior of electron and hole transport in semiconductor materials is influenced by lattice-mismatch at the interface. It is well known that carrier scattering in a confined region is dramatically reduced. In this work, we studied the effects of coupling both the strain and confinement simultaneously. We report on the fabrication and characterization of nanoscale planar, wall-like, and wire-like Si/SiO2 structures. As the Si nanostructure dimensions were scaled down to the quantum regime by thermal oxidation of the Si, changes to the band structure and carrier effective mass were observed by both optical and electrical techniques. Transient-time response measurements were performed to examine the carrier generation and recombination behavior as a function of scaling. Signal rise times decreased for both carrier types by an order of magnitude as Si dimensions were reduced from 200 to 10 nm, meaning that the carrier velocity is increasing with smaller scale structures. This result is indicative of decreased Si bandgap energy and carrier effective mass. Photoluminescence measurements taken at 50K showed changes in the PL response peak energies, which illustrates changes in the band structure, as the Si/SiO2 dimensions are scaled.
We report the development of a sensitive and a label-free electrochemical immunosensing platform for the detection of cardiac biomarker troponin I (cTnI) using tungsten trioxide nanorods (WO3 NRs). The low-temperature hydrothermal technique was employed for the controlled synthesis of WO3 NRs. Thin films of 3-aminopropyltriethoxy saline (APTES)-functionalized WO3 NRs were deposited on indium tin oxide (ITO)-coated glass substrate (0.5 cm × 1 cm) using electrophoretic deposition technique. The covalent immobilization of cTnI antibody onto functionalized WO3 NRs electrode was accomplished using EDC-NHS [1-(3-(dimethylamino)-propyl)-3-ethylcarbodiimide hydrochloride and N-hydroxysulfosuccinimide] chemistry. The structural and morphological characterizations of WO3 NRs and functionalized WO3 NRs were studied using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and electrochemical techniques. The impedimetric response study of the proposed immunosensor demonstrates high sensitivity [6.81 KΩ mL·cm2)] in a linear detection range of 0.01–10 ng/mL. The excellent selectivity, good reproducibility, and long-term stability of the proposed immunosensing platform indicate WO3 NRs as a suitable platform for the development of a point-of-care biosensing device for cardiac detection.
Mental health and wellbeing, including addressing impacts of historical trauma and substance use among young people, has been identified as a key priority by Indigenous communities and leaders across Canada and globally. Yet, research to understand mental health among young Indigenous people who have used drugs is limited.
To examine longitudinal risk and strengths-based factors associated with psychological distress among young Indigenous people who use drugs.
The Cedar Project is an ongoing cohort study involving young Indigenous people who use drugs in Vancouver, Prince George, and Chase, British Columbia, Canada. This study included participants who completed the Symptom Checklist-90-Revised, returned for follow-up between 2010 and 2012, and completed the Childhood Trauma Questionnaire. Adjusted linear mixed-effects models estimated effects of study variables on changes in area T-scores of psychological distress.
Of 202 eligible participants, 53% were women and the mean age was 28 years. Among men, childhood maltreatment (emotional abuse, physical abuse, sexual abuse, physical neglect), any drug use, blackouts from drinking, and sex work were associated with increased distress. Among women, childhood maltreatment (emotional abuse, physical abuse, physical neglect), blackouts from drinking, and sexual assault were associated with increased distress, while having attempted to quit using drugs was associated with reduced distress. Marginal associations were observed between speaking their traditional language and living by traditional culture with lower distress among men.
Culturally safe mental wellness interventions are urgently needed to address childhood trauma and harmful coping strategies that exacerbate distress among young Indigenous people who use drugs.
This paper addresses the finite amplitude instability of stably stratified non-isothermal parallel flow in a vertical channel filled with a highly permeable porous medium. A cubic Landau equation is derived to study the limiting value of growth of instabilities under nonlinear effects. The non-Darcy model is considered to describe the flow instabilities in a porous medium. The nonlinear results are presented for air as well as water. The analysis is carried out in the vicinity of as well as away from the critical point (bifurcation point). It is found that when the medium is saturated by water then supercritical bifurcation is the only type of bifurcation at and beyond the bifurcation point. However, for air, depending on the strength of the flow and permeability of the medium, both supercritical and subcritical bifurcations are observed. The influence of nonlinear interaction of different harmonics on the heat transfer rate, friction coefficient, nonlinear kinetic energy spectrum and disturbance flow is also studied in both supercritical as well as subcritical regimes. The variation of neutral stability curves of parallel mixed convection flow of air with wavenumber reveals that a bifurcation that is supercritical for some wavenumber may be subcritical or vice versa at other nearby wavenumbers. The analysis of the nonlinear kinetic energy spectrum of the fundamental disturbance also supports the existence of supercritical/subcritical bifurcation at and away from the critical point. The effect of different harmonics on the pattern of secondary flow, based on linear stability theory, is also studied and a significant influence is found, especially in the subcritical regime.
Oscillating two-stream instability (OTSI) of a high amplitude laser or a plasma wave is investigated in plasmas with strongly coupled ions. It is shown that in some parameter regime, the pressure of strongly coupled ions becomes negative, which leads to enhance the bunching of ion and concomitant destabilization of OTSI. Applications of these results to ion accelerator and inertial confinement fusion experiments are discussed.
This study examined the hypothesis that xanthosine (XS) treatment would promote mammary-specific gene expression and stem cell transcripts and have a positive influence on milk yield of dairy goats. Seven primiparous Beetal goats were assigned to the study. Five days after kidding, one gland (either left or right) was infused with XS (TRT) twice daily for 3 d and the other gland with no XS infusion served as a control (CON). Mammary biopsies were collected at 10 d and RNA was isolated. Gene expression analysis of milk synthesis genes, mammary stem/progenitor cell markers, cell proliferation and differentiation markers were performed using real time quantitative PCR (RT-qPCR). Results showed that the transcripts of milk synthesis genes (BLG4, CSN2, LALBA, FABP3, CD36) and mammary stem/progenitor cell markers (ALDH1 and NR5A2) were increased in as a result of XS treatment. Average milk yield in TRT glands was increased marginally (approximately ~2% P = 0·05, paired t-test) per gland relative to CON gland until 7 wk. After 7 wk, milk yield of TRT and CON glands did not differ. Analysis of milk composition revealed that protein, lactose, fat and solids-not-fat percentages remained the same in TRT and CON glands. These results suggest that XS increases expression of milk synthesis genes, mammary stem/progenitor cells and has a small effect on milk yield.