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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.
At GE Research, we are combining “physics” with artificial intelligence and machine learning to advance manufacturing design, processing, and inspection, turning innovative technologies into real products and solutions across our industrial portfolio. This article provides a snapshot of how this physical plus digital transformation is evolving at GE.
To compare round window niche visibility as seen endoscopically during cochlear implant surgery with pre-operative high-resolution computed tomography of the temporal bone.
Nineteen patients scheduled for cochlear implantation, aged 2–20 years, were referred for computed tomography from October 2016 to March 2018. Angles were measured between the lines passing through the mid-sagittal plane and cochlear basal turn on the scans. Endoscopic round window niche visibility during posterior tympanotomy was categorised as: type I = 100 per cent, type IIa = more than 50 per cent, type IIb = less than 50 per cent or type III = 0 per cent. Pre-operative computed tomography measurements were used to predict round window niche visibility before surgery and correlated with intra-operative findings.
The mean (range) of pre-operative angles on computed tomography for endoscopic visibility types I, IIa and IIb, were 64.06° (61.16–69.37°), 63.81° (58.61–71.35°) and 56.48° (50.37–59.05°), respectively, a statistically significant finding (one-way analysis of variance test, p = 0.016).
Pre-operative high-resolution temporal bone computed tomography measurements are useful in predicting round window niche visualisation as viewed endoscopically during posterior tympanotomy. The angle was more acute in type IIb compared to type I.
A mother's nutritional choices while pregnant may have a great influence on her baby's development in the womb and during infancy. There is evidence that what a mother eats during pregnancy interacts with her genes to affect her child's susceptibility to poor health outcomes including childhood obesity, pre-diabetes, allergy and asthma. Furthermore, after what an infant eats can change his or her intestinal bacteria, which can further influence the development of these poor outcomes. In the present paper, we review the importance of birth cohorts, the formation and early findings from a multi-ethnic birth cohort alliance in Canada and summarise our future research directions for this birth cohort alliance. We summarise a method for harmonising collection and analysis of self-reported dietary data across multiple cohorts and provide examples of how this birth cohort alliance has contributed to our understanding of gestational diabetes risk; ethnic and diet-influences differences in the healthy infant microbiome; and the interplay between diet, ethnicity and birth weight. Ongoing work in this birth cohort alliance will focus on the use of metabolomic profiling to measure dietary intake, discovery of unique diet–gene and diet–epigenome interactions, and qualitative interviews with families of children at risk of metabolic syndrome. Our findings to-date and future areas of research will advance the evidence base that informs dietary guidelines in pregnancy, infancy and childhood, and will be relevant to diverse and high-risk populations of Canada and other high-income countries.
Fifth generation (5G) is the current hot topic of the world's leading telecommunication companies. The compact designs of antennas made it possible for them to resonate at higher frequencies, thus to enable the devices to attain higher data rate as compared to 4G technology. Data rate of 5G technology for low mobility users is expected to be 50.0 Gbps and for high mobility users it is 5.0 Gbps. On the other hand, International telecommunication union's objective for 5G is 3 times more spectrally efficient thanlong-term evolution (LTE). The paper has carried out meticulous study over the impact of 5G antennas on the size of antenna, size/type of substrate, gain, efficiency, and isolation, etc. Also, different arrays andmultiple input multiple outputs (MIMOs) with patch antenna, magneto electric-dipole, microstrip grid array antenna, folded dipole, series-fed array, connected antenna array, MIMO are studied. The paper also includes the existing technology i.e 4G LTE and their isolation enhancement approaches. Many of the designs used the reflector plates to reduce the back lobe radiation problem in MIMO/array antennas to increase front-to-back ratio. The gain in 5G antennas can be increased by using balun, parasitic element as directors, multiple notch structures, three identical slot sub-arrays, etc. Mathematical equations of multi-element/port antennas are included to model the designed antennas. The beam steering is also included for the 5G technology in this paper.
A non-perturbative nonlinear theory for moderately dense gas–solid suspensions is outlined within the framework of the Boltzmann–Enskog equation by extending the work of Saha & Alam (J. Fluid Mech., vol. 833, 2017, pp. 206–246). A linear Stokes’ drag law is adopted for gas–particle interactions, and the viscous dissipation due to hydrodynamic interactions is incorporated in the second-moment equation via a density-corrected Stokes number. For the homogeneous shear flow, the present theory provides a unified treatment of dilute to dense suspensions of highly inelastic particles, encompassing the high-Stokes-number rapid granular regime (
) and its small-Stokes-number counterpart, with quantitative agreement for all transport coefficients. It is shown that the predictions of the shear viscosity and normal-stress differences based on existing theories deteriorate markedly with increasing density as well as with decreasing Stokes number and restitution coefficient.
To propose a new classification of inner-ear anomalies that is more clinically oriented and surgically relevant: the SMS (Sawai Man Singh) classification of cochleovestibular malformations.
A retrospective multicentric study was conducted of 436 cochlear implantations carried out in 3 Indian tertiary care institutes. Patients with anomalous anatomy were included and classified, as per the new SMS classification, into cochleovestibular malformation types I, II, III and IV, based on cochlear morphology, modiolus and lamina cribrosa.
There were 19, 23, 8 and 4 patients with cochleovestibular malformation types I, II, III and IV, respectively. Two-year post-operative Meaningful Auditory Integration Scale scores were statistically analysed.
This new classification for inner-ear anomalies is a simpler, more practical, outcome-oriented classification that can be used to better plan the surgery. These merits make it a more uniform classification for recording results.
Introduction: Abdominal pain is one of the most frequent reasons for an emergency department (ED) visit. Most cases are functional and no therapy has proven effective. Our objective was to determine if hyoscine butylbromide (HBB) (BuscopanTM) is effective for children who present to the ED with functional abdominal pain. Methods: We conducted a randomized, blinded, superiority trial comparing HBB 10 mg plus acetaminophen placebo to oral acetaminophen 15 mg/kg (max 975 mg) plus HBB placebo using a double-dummy approach. We included children 8-17 years presenting to the ED at London Health Sciences Centre with colicky abdominal pain rated >40 mm on a 100 mm visual analog scale (VAS). The primary outcome was VAS pain score at 80 minutes post-administration. Secondary outcomes included adverse effects; caregiver satisfaction with pain management using a five-item Likert scale; recidivism and missed surgical diagnoses within 24-hours of discharge. Analysis was based on intention to treat. Results: We analyzed 225 participants (112 acetaminophen; 113 HBB). The mean (SD) age was 12.4 (3.0) years and 148/225 (65.8%) were females. Prior to enrollment, the median (IQR) duration of pain prior was 2 (4.5) hours and analgesia was provided to 101/225 (44.9%) of participants. The mean (SD) pre-intervention pain scores in the acetaminophen and HBB groups were 62.7 (15.9) mm and 60.3 (17.3) mm, respectively. At 80 minutes, the mean (SD) pain scores in the acetaminophen and HBB groups were 30.1 (28.8) mm and 29.4 (26.4) mm, respectively and there were no significant differences adjusting for pre-intervention scores (p = 0.96). The median (IQR) caregiver satisfaction was high in the acetaminophen [5 (2)] and HBB [5 (1)] groups (p = 0.79). The median (IQR) length of stay between acetaminophen [235 (101)] and HBB [234 (103)] was not significantly different (p = 0.53). The proportion of participants with a return visit for abdominal pain was 4/112 (3.5%) in the acetaminophen group and 6/113 (5.3%) in the HBB group. The most common adverse effect was nausea (9% in each group) and there were no significant differences in adverse effects between acetaminophen (26/112, 23.2%) and HBB (31/113, 27.4%) (p = 0.52). There were no missed surgical diagnoses. Conclusion: For children with presumed functional abdominal pain who present to the ED, both acetaminophen and HBB produce a clinically important (VAS < 30 mm) reduction in pain and should be routinely considered in this clinical setting.
Introduction: Acute aortic syndrome (AAS) is a time sensitive aortic catastrophe that is often misdiagnosed. There are currently no Canadian guidelines to aid in diagnosis. Our goal was to adapt the existing American Heart Association (AHA) and European Society of Cardiology (ESC) diagnostic algorithms for AAS into a Canadian evidence based best practices algorithm targeted for emergency medicine physicians. Methods: We chose to adapt existing high-quality clinical practice guidelines (CPG) previously developed by the AHA/ESC using the GRADE ADOLOPMENT approach. We created a National Advisory Committee consisting of 21 members from across Canada including academic, community and remote/rural emergency physicians/nurses, cardiothoracic and cardiovascular surgeons, cardiac anesthesiologists, critical care physicians, cardiologist, radiologists and patient representatives. The Advisory Committee communicated through multiple teleconference meetings, emails and a one-day in person meeting. The panel prioritized questions and outcomes, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. The algorithm was prepared and revised through feedback and discussions and through an iterative process until consensus was achieved. Results: The diagnostic algorithm is comprised of an updated pre test probability assessment tool with further testing recommendations based on risk level. The updated tool incorporates likelihood of an alternative diagnosis and point of care ultrasound. The final best practice diagnostic algorithm defined risk levels as Low (0.5% no further testing), Moderate (0.6-5% further testing required) and High ( >5% computed tomography, magnetic resonance imaging, trans esophageal echocardiography). During the consensus and feedback processes, we addressed a number of issues and concerns. D-dimer can be used to reduce probability of AAS in an intermediate risk group, but should not be used in a low or high-risk group. Ultrasound was incorporated as a bedside clinical examination option in pre test probability assessment for aortic insufficiency, abdominal/thoracic aortic aneurysms. Conclusion: We have created the first Canadian best practice diagnostic algorithm for AAS. We hope this diagnostic algorithm will standardize and improve diagnosis of AAS in all emergency departments across Canada.
Since the measurement of residual stress by X-ray diffraction techniques is dependent on the difference in angle of a diffraction peak maximum when the sample is examined consecutively with its surface at two different angles to the diffracting planes, it is important that these diffraction angles be obtained precisely, preferably with an accuracy of ± 0.01 deg. 2θ. Similar accuracy is desired in precise lattice parameter determination. In such measurements, it is imperative that the diffractometer be well-aligned. It is in the context of diffractometer alignment with the aid of a silicon powder standard free of residual stress that the diffraction peak analysis techniques described here have been developed, preparatory to residual stress determinations.
To recount experience with cerebrospinal fluid otorrhoea and temporal bone meningoencephalocele repair in a tertiary care hospital.
A retrospective review was conducted of 16 cerebrospinal fluid otorrhoea and meningoencephalic herniation patients managed surgically from 1991 to 2016.
Aetiology was: congenital (n = 3), post-traumatic (n = 2), spontaneous (n = 1) or post-mastoidectomy (n = 10). Surgical repair was undertaken by combined middle cranial fossa and transmastoid approach in 3 patients, transmastoid approach in 2, oval window plugging in 1, and subtotal petrosectomy with middle-ear obliteration in 10. All patients had successful long-term outcomes, except one, who experienced recurrence after primary stage oval window plugging, but has been recurrence-free after second-stage subtotal petrosectomy with middle-ear obliteration.
Dural injury or exposure in mastoidectomy may lead to cerebrospinal fluid otorrhoea or meningoencephalic herniation years later. Congenital, spontaneous and traumatic temporal bone defects may present similarly. Middle cranial fossa dural repair, transmastoid multilayer closure and subtotal petrosectomy with middle-ear obliteration were successful procedures. Subtotal petrosectomy with middle-ear obliteration offers advantages over middle cranial fossa dural repair alone; soft tissue closure is more robust and is preferred in situations where hearing preservation is not a priority.
We report the synthesis and optical properties of pure ZnS and Ag doped ZnS nanostructures. ZnS(Ag) was synthesized by using the hydrothermal technique and later annealed at different temperatures under vacuum conditions. It was observed that the photoluminescence (PL) emission from the ZnS(Ag) nanostructures can be easily tuned from the blue (445 nm) to green (530 nm) region of visible light by varying the annealing temperature. This tunability has been attributed to the introduction of excess sulfur vacancy states, which is evident from the PL excitation spectra. This observed change in the PL emission wavelength can be highly beneficial in the imaging screens where ZnS is regularly used and can be easily interfaced with the silicon photodiodes showing maximum sensitivity at 550 nm.
A variety of paediatric tracheostomy tubes are available. This article reviews the tubes in current use at Great Ormond Street Hospital for Children and Evelina London Children's Hospital.
This paper outlines our current preferences, and the particular indications for different tracheostomy tubes, speaking valves and other attachments.
Our preferred types of tubes have undergone significant design changes. This paper also reports further experience with certain tubes that may be useful in particular circumstances. An updated sizing chart is included for reference purposes.
The choice of a paediatric tracheostomy tube remains largely determined by individual clinical requirements. Although we still favour a small range of tubes for use in the majority of our patients, there are circumstances in which other varieties are indicated.
This study investigates the phenomenon of targeted energy transfer (TET) from a linear oscillator to a nonlinear attachment behaving as a nonlinear energy sink for both transient and stochastic excitations. First, the dynamics of the underlying Hamiltonian system under deterministic transient loading is studied. Assuming that the transient dynamics can be partitioned into slow and fast components, the governing equations of motion corresponding to the slow flow dynamics are derived and the behaviour of the system is analysed. Subsequently, the effect of noise on the slow flow dynamics of the system is investigated. The Itô stochastic differential equations for the noisy system are derived and the corresponding Fokker–Planck equations are numerically solved to gain insights into the behaviour of the system on TET. The effects of the system parameters as well as noise intensity on the optimal regime of TET are studied. The analysis reveals that the interaction of nonlinearities and noise enhances the optimal TET regime as predicted in deterministic analysis.
To ascertain the feasibility of endoscopic (4 mm) stapedotomy, and compare intra- and post-operative variations with microscopic stapedotomies.
Forty otosclerosis patients were scheduled for microscopic or endoscopic stapedotomy. Intra-operative variables compared were: incision, canalplasty, canal wall curettage for ossicular assessment, chorda tympani manipulation, ability to perform stapes footplate perforation before its supra-structure removal, and operative time. Post-operative variables compared were ear pain and hearing improvement.
Of the 20 microscopy patients, 4 required endaural incision and canalplasty because of canal overhangs, and 7 required canal wall curettage for ossicular assessment. None of the 20 endoscopy patients required these procedures. Chorda tympani was manipulated in 13 and 6 patients in the microscopy and endoscopy groups respectively, while the stapes footplate could be perforated in 5 and 11 patients respectively. Mean operative time was 50.25 and 76.05 minutes in the microscopy and endoscopy groups respectively. In the endoscopy group, mean air–bone gap was 37.12 and 10.73 dB pre- and post-operation respectively; in the microscopy group, these values were 35.95 and 13.81 dB.
Endoscopic stapedotomy has comparable hearing outcomes. Sinonasal endoscope serves as a better tool for: minimal incision, canalplasty avoidance, less chorda tympani mobilisation, and stapes footplate perforation ability.
To evaluate the survival outcomes and toxicities experienced by non-metastatic head and neck cancer (HNC) patients receiving modulated radiotherapy (RT).
Materials and methods
A total of 608 HNC patients treated consecutively from March 2010 to December 2014 with common subsites (oral cavity, oropharynx, hypopharynx, larynx and nasopharynx) of HNCs formed the study group. Eligible patients included those treated with radical or postoperative RT between March 2010 and December 2014. More than 90% patients received modulated RT [intensity-modulated radiotherapy (IMRT) or volumetric-modulated arc therapy (VMAT)] with concurrent chemotherapy as per stage guidelines. Demographic parameters and disease-related factors were analysed. Disease-free survival (DFS) was calculated from end date of RT till last follow-up or last date of disease control. Overall survival (OS) was calculated from date of registration to last follow-up date if alive. The primary endpoint was survival. The statistical analyses were performed using SPSS version 20.0 and Kaplan–Meier method was used for calculation survival.
Among the evaluable patients, the median age was 60 years (range: 16–93) with male preponderance (male:female – 513:95). Majority were squamous cell carcinoma 93·4% (568/608). The subsites treated were oral cavity 36·8% (224). oropharynx 26·4% (161), larynx 19·7% (120), hypopharynx 10% (62) and nasopharynx 6·4% (41). RT intent was radical in 63·5% (386) and postoperative in 36·5% (222), with 59·5% (362) receiving concurrent chemotherapy. At last follow-up, 348 (57·2%) patients were alive, 169 (27·7%) patients had succumbed to disease and 120 (24·6%) patients had recurrent disease. Out of 120 recurrent cases loco-regional recurrence, nodal recurrence and distant metastases were seen in 62 (51·7%), 25 (20·8%), 33 (27·5%), respectively. In the entire study cohort at 2 year OS and DFS was 80 and 79% whereas 3 years OS and DFS was 70 and 75%, respectively.
In our study, 2 years and 3 years OS and DFS rates are found comparable to the international data with acceptable toxicity profile with the use of modulated RT. It seems to be possible because of stringent departmental protocols and good medical physics support. Our data re-validates need and benefit of advanced RT techniques like IG-IMRT and VMAT for both postoperative and radical HNC treatment at the cost of minimal long-term side effects. Future stringent follow-up and quality of life issues are being considered in a prospective manner.