Seismic Bearing Capacity of Strip Footing Resting on Reinforced Earth Bed

With an increase in demand for construction the use of poor soils becomes imperative. Soil bearing capacity and settlement play an important role in the design of foundations. Seismicity of the site is another important parameter in the design of the foundation for a structure. Hence seismic bearing capacity of soil becomes an important component in the design. In weak soils often deep foundations are recommended on account of the low soil bearing capacity available. In poor soils, ground improvement techniques are commonly used to improve the soil bearing capacity. Reinforcing earth with geo synthetic is one such technique adopted in practice. This is preferred due to its cost effectiveness as in most of the engineering projects economy plays an important role. If the weak soil is improved by using geo synthetic, then it becomes feasible to use shallow foundations instead of deep foundations for the same structure, thus effecting economy. Shallow foundations still remain the most used foundation type in construction due to its economy and ease in construction. In this paper an attempt has been made to develop an analytical approach to obtain the seismic bearing capacity of a strip footing resting on reinforced earth. The approach is based on the analysis proposed by Binquet and Lee (1975b) for a strip footing subjected to static load. Both vertical and horizontal accelerations have been considered in terms of seismic coefficients, αh and αv. Results have been presented in the form of non - dimensional charts from which seismic bearing capacity can be obtained, conveniently. Both rupture strength and frictional resistance criteria, have been taken into account in preparing these charts. Charts incorporate horizontal seismic acceleration coefficient, αh = 0.0 and 0.10. The value of vertical seismic acceleration coefficient, αv, is taken as 2/3αh. An illustrative example has been included for a lucid understanding

Clinicopathological and immunohistochemical analysis of Sarcomatoid carcinoma of head and neck mucosal region: a retrospective analysis

Background: Sarcomatoid carcinoma is a biphasic tumour comprising both of malignant epithelial and mesenchymal elements derived monoclonally from same stem cells. These are unusual variants of squamous cell carcinoma and constitute less than 1% of the head and neck mucosal tumors. Only few studies have been published and needs more understanding to establish treatment guidelines. The aim of this study was to review the cases of carcinosarcoma arising from mucosal sites of head and neck and study their clinical, histological and Immunohistochemical features.Methods: Retrospective data and slides of histologically proven sarcomatoid carcinoma over a period of thirty -four months between January 2016 - October 2018 were retrieved and evaluated for various clinical and histopathological parameters.Results: Total of 22 cases were included in the study and the mean age of presentation was 58years with male: female ration 2:1. Most of the patients (81.8%) presented with a mass lesion of less than 6 months duration. The most common site was oral cavity (68.1%) followed by larynx (22.7%). Clinical stage was known in eleven cases. One case presented with pulmonary metastasis. Histopathologically, epithelial differentiation was identified in nine cases (41%) on morphology and in thirteen cases could be highlighted by cytokeratin positivity. The Mesenchymal component was arranged in sheets (63.7%) and fascicles (31.8%). Marked anaplasia and brisk mitosis wereseen in 54.5% and 19.3% respectively.  On immunohistochemistry all 22 cases were positive for Vimentin, twenty cases were positive for cytokeratin/EMA and aberrant mesenchymal markers were expressed in 10% of cases.  Follow up was available in eighteen cases out of which fourteen cases died within one year of diagnosis.Conclusions: Diagnosis of sarcomatoid carcinoma is challenging especially on small biopsy because of overlapping features with other spindle cell tumors. Understanding the clinicopathological features facilitates their diagnosis and effective clinical management

Prospective Home-use Study on Non-invasive Neuromodulation Therapy for Essential Tremor.

Highlights: This prospective study is one of the largest clinical trials in essential tremor to date. Study findings suggest that individualized non-invasive neuromodulation therapy used repeatedly at home over three months results in safe and effective hand tremor reduction and improves quality of life for many essential tremor patients. Background: Two previous randomized, controlled, single-session trials demonstrated efficacy of non-invasive neuromodulation therapy targeting the median and radial nerves for reducing hand tremor. This current study evaluated efficacy and safety of the therapy over three months of repeated home use. Methods: This was a prospective, open-label, post-clearance, single-arm study with 263 patients enrolled across 26 sites. Patients were instructed to use the therapy twice daily for three months. Pre-specified co-primary endpoints were improvements on clinician-rated Tremor Research Group Essential Tremor Rating Assessment Scale (TETRAS) and patient-rated Bain & Findley Activities of Daily Living (BF-ADL) dominant hand scores. Other endpoints included improvement in the tremor power detected by an accelerometer on the therapeutic device, Clinical and Patient Global Impression scores (CGI-I, PGI-I), and Quality of Life in Essential Tremor (QUEST) survey. Results: 205 patients completed the study. The co-primary endpoints were met (p≪0.0001), with 62% (TETRAS) and 68% (BF-ADL) of \u27severe\u27 or \u27moderate\u27 patients improving to \u27mild\u27 or \u27slight\u27. Clinicians (CGI-I) reported improvement in 68% of patients, 60% (PGI-I) of patients reported improvement, and QUEST improved (p = 0.0019). Wrist-worn accelerometer recordings before and after 21,806 therapy sessions showed that 92% of patients improved, and 54% of patients experienced ≥50% improvement in tremor power. Device-related adverse events (e.g., wrist discomfort, skin irritation, pain) occurred in 18% of patients. No device-related serious adverse events were reported. Discussion: This study suggests that non-invasive neuromodulation therapy used repeatedly at home over three months results in safe and effective hand tremor reduction in many essential tremor patients

Biochemical and structural characterization of mycobacterial aspartyl-tRNA synthetase AspS, a promising TB drug target.

The human pathogen Mycobacterium tuberculosis is the causative agent of pulmonary tuberculosis (TB), a disease with high worldwide mortality rates. Current treatment programs are under significant threat from multi-drug and extensively-drug resistant strains of M. tuberculosis, and it is essential to identify new inhibitors and their targets. We generated spontaneous resistant mutants in Mycobacterium bovis BCG in the presence of 10× the minimum inhibitory concentration (MIC) of compound 1, a previously identified potent inhibitor of mycobacterial growth in culture. Whole genome sequencing of two resistant mutants revealed in one case a single nucleotide polymorphism in the gene aspS at 535GAC>535AAC (D179N), while in the second mutant a single nucleotide polymorphism was identified upstream of the aspS promoter region. We probed whole cell target engagement by overexpressing either M. bovis BCG aspS or Mycobacterium smegmatis aspS, which resulted in a ten-fold and greater than ten-fold increase, respectively, of the MIC against compound 1. To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. Finally, to aid hit-to-lead optimization, the crystal structure of apo M. smegmatis AspS was determined to a resolution of 2.4 Å

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Multi-dimensional modeling of natural gas ignition, combustion and pollutant formation in direct injection engines.

Models for describing ignition, combustion and pollutant formation in direct injection (DI) natural gas engines are developed in this work. These models are coupled with a multi-dimensional reactive flow code KIVA-3 to study the energy conversion process in DI engines. Emphasis is placed on gaining a fundamental understanding of each of these processes by studying them in detail individually. Ignition of natural gas injected under compression ignition conditions is simulated by using a detailed chemical kinetic mechanism for natural gas oxidation (consisting of 22 species and 104 elementary reactions) in conjunction with KIVA-3. The mechanism is chosen after a systematic study of its predictive capabilities under typical end-of-compression conditions in DI engines. It is shown that the choice of a suitable detailed kinetic mechanism is essential to account for all the thermodynamic and fuel composition related factors that affect the ignition process in DI natural gas engines. Calculations of ignition delay of different blends of natural gas in a combustion bomb compare very well with measurements. The coupled detailed kinetics-multi-dimensional flow model is also used to investigate the effect of parameters like chemical additives, injection rate and fuel temperature on ignition delay and ignition location. It is established that a specified mass of fuel burned is a more consistent criterion to detect the length of the ignition delay period than pressure rise while comparing different natural gas blends over a range of temperatures and pressures. After ignition occurs, combustion of injected fuel with air is described using a mixing controlled model. Fuel and air are assumed to burn in stoichiometric proportions at a rate proportional to the rate of mixing. Transition from detailed kinetics to the combustion model is assumed to occur when 4% of the total injected fuel has burned. Pollutant formation is modeled by implementing the extended Zeldovich kinetic mechanism for thermal nitric oxide formation in KIVA-3. Finally, calculations are done using the geometry of a medium size heavy-duty diesel engine with pure methane as fuel. It is shown that operating parameters like engine speed and load, coupled with different strategies for injection timing and level of boost, can have a significant impact on engine output. The tradeoffs between performance and emissions are discussed in terms of variation in engine operating conditions and injection strategies.Ph.D.Applied SciencesAutomotive engineeringMechanical engineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/131157/2/9840494.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/131157/4/Agarwal_Open Access 2 Ph.D. dissertation (9840494).pd

Clinical Outcomes Of Descemet Membrane Endothelial Keratoplasty (DMEK) Cases At A Tertiary Care Hospital In North India

Abstract Purpose: To analyze the clinical outcomes of DMEK in 200 cases. Methods: Prospective interventional study of cases of endothelial dysfunction (different etiologies) operated by a single surgeon. Endothelial Cell Density of the Donor cornea was > 2500 cells /mm2 and donor corneal scroll was prepared by surgeon at the time of surgery. Postoperative Best Corrected Visual Acuity (BCVA), Endothelial Cell Density and complications were analyzed till one year postoperatively. Results: The indications were Bullous Keratopathy in 128 eyes (64%), Previous Failed Graft in 36 (18%), Fuch’s endothelial corneal dystrophy (FECD) in 34 (17%) and Congenital Hereditary Endothelial Dystrophy (CHED) in 2(1%) cases. In phakic eyes with cataract 18 (9%), DMEK was combined with cataract surgery. BCVA of 6/6 was achieved in 8 (4%) eyes, 6/9 – 6/12 in 110 (55%) eyes, 6/18 – 6/36 in 53 (26.5%) eyes, 6/60 – 4/60 in 20 (10%) eyes and <3/60 in 9 (4.5%) eyes at the end of one year. Mean Endothelial Cell Density (ECD) decreased from 2674±158 (Before Surgery) to 2125±271 & 1940±275 at 6 months and 1 year respectively. The commonest complication was Descemet Membrane(DM) detachment in 22 eyes (11%) eyes of which 9 eyes required rebubbling. 4 eyes had primary graft failure. Conclusion: DMEK is a effective procedure in endothelial diseases with encouraging clinical outcomes & less complications . Keywords: Clinical,outcome,hospita

Ghosal hematodiaphyseal dysplasia – A remediable cause of refractory anemia: A case report

Background: The cardinal features of Ghosal hematodiaphyseal dysplasia (GHDD) include severe myelopathic anemia with increased density of long bones with or without deformities. Early diagnosis helps in the institution of corticosteroid therapy, improving hematological parameters and bone changes. Case report: We report a 6-year-old girl of consanguineous birth who presented with progressive anemia and thrombocytopenia without bony deformities, lymphadenopathy, or organomegaly. The skeletal survey was normal. Bone marrow was severely hypocellular. She had a homozygous point mutation in exon 12 of the TBXAS1 gene and was diagnosed with GHDD. She was started on oral corticosteroids and is on follow-up, with reduced transfusion needs. Conclusion: GHDD, although rare, must be considered a differential diagnosis for difficult-to-treat anemia as it is simple to diagnose and easy to treat. Even without an obvious abnormality in the skeletal survey, one needs to keep this possibility in mind

Comparative evaluation of sealing ability of light cure glass ionomer cement and light cure composite as coronal sealing material: An in vitro study

Aim: To compare and evaluate the sealing ability of light cure composite and light cure GIC as coronal sealing materials. Materials and Methods: 30 extracted human teeth were divided into three experimental groups of 10 teeth each. The teeth in group I are obturated without coronal seal, teeth in group II are obturated with light cure GIC (3M ESPE VITREMER) as coronal seal and teeth in group III are obturated with light cure composite(3M ESPE filtek z250) as coronal seal, after removing 2mm of coronal gutta percha. These teeth (crown portion) are then suspended in methylene blue, sealed and kept for 72 hours, to observe the amount of dye penetration. After 72 hours teeth were removed, washed under running water, dried and sectioned longitudinally, separating buccal and lingual halves. The linear extent of dye penetration was measured from cavosurface margin of the access cavity to the most apical extent of dye penetration point. The length from the cavosurface margin to the apex of the tooth was also measured and percentage linear micro leakage was estimated. Statistical Analysis: Data was statistically analyzed using one-way ANOVA followed by Post-Hoc Multiple comparison (Bonferroni). Results: In the present study specimens in group I showed the maximum percentage of linear microleakage of 31.51 percent. The specimens in group II showed the minimal amount of linear micro leakage of 6.49 percent. Conclusion: It can be concluded coronal seal reduces the micro leakage, and light cure GIC has better coronal sealing ability