Vibrations of viscoelastically damped laminated structures.

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COVID-19 Disrupts U.S. Higher Education Industry Reimagining the Future

As people and businesses around the world enter the new year, businesses, economists, policy makers and risk management specialists begin to develop a list of existing and new sources of global risks. Ringing in “Year 2020” was no different. But the possibility that, COVID-19 would turn into global pandemic did not make the list. The World Health Organization (WHO) labeled the new virus a pandemic in the beginning of year 2020. China recognized this highly contagious and dangerous virus in December 2019. As we welcomed year 2020, the coronavirus crisis (COVID-19) began to upend the economies, industries as well as the lives of people around the world. Using secondary research sources, I will present the challenges that HEI will face in years to come in the aftermath of COVID-19

Structural dynamic modification using additive damping

In order to control dynamic response in structures and machines, modifications using additive viscoelastic damping materials are highlighted. The techniques described for analysis include analytical methods for structural elements, FEM and perturbation methods for reanalysis or structural dynamic modification for complex structures. Optimisation techniques used for damping effectiveness include multi-parameter optimisation techniques and a technique using dynamic sensitivity analysis and structural dynamic modification. These have been applied for optimum dynamic design of structures incorporating viscoelastic damping. Some current trends for vibration control are also discussed

The Impact of Palatal Expansion on Airway and Breathing

Mini-implant assisted rapid palatal expansion (MARPE) is used to correct transverse maxillary deficiencies in orthodontics. While MARPE\u27s influence on occlusal stability and maxillary expansion is recognized, its impact on facial aesthetics, soft tissue morphology, and nasal airway function requires further examination. Our study analyzed the changes in facial soft tissue and airway dimensions in patients undergoing MARPE treatment

Multisystem inflammatory syndrome in children (MIS-C) and neonates (MIS-N) associated with COVID-19: optimizing definition and management

During the SARS-CoV-2-associated infection (COVID-19), pandemic initial reports suggested relative sparing of children inversely related to their age. Children and neonates have a decreased incidence of SARS-CoV-2 infection, and if infected they manifested a less severe phenotype, in part due to enhanced innate immune response. However, a multisystem inflammatory syndrome in children (MIS-C) or paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 emerged involving coronary artery aneurysms, cardiac dysfunction, and multiorgan inflammatory manifestations. MIS-C has many similarities to Kawasaki disease and other inflammatory conditions and may fit within a spectrum of inflammatory conditions based on immunological results. More recently neonates born to mothers with SARS-CoV-2 infection during pregnancy demonstrated evidence of a multisystem inflammatory syndrome with raised inflammatory markers and multiorgan, especially cardiac dysfunction that has been described as multisystem inflammatory syndrome in neonates (MIS-N). However, there is a variation in definitions and management algorithms for MIS-C and MIS-N. Further understanding of baseline immunological responses to allow stratification of patient groups and accurate diagnosis will aid prognostication, and inform optimal immunomodulatory therapies. IMPACT: Multisystem inflammatory system in children and neonates (MIS-C and MIS-N) post COVID require an internationally recognized consensus definition and international datasets to improve management and plan future clinical trials. This review incorporates the latest review of pathophysiology, clinical information, and management of MIS-C and MIS-N. Further understanding of the pathophysiology of MIS-C and MIS-N will allow future targeted therapies to prevent and limit clinical sequelae

Topical treatments to reduce severity of radiation dermatitis in breast cancer patients-a systematic review

open access journalBreast cancer (BC) patients are likely to undergo radiotherapy (RT) treatment which may lead to the development of the skin toxicity, radiodermatitis (RD). The purpose of this systematic review is to evaluate the effectiveness of topical interventions in reducing the severity of RD in females BC patients. Appropriate clinical studies were independently identified through a bibliographic search in PubMed and clinicaltrials.gov. Nine randomised, controlled clinical trials (RCTs) which stated a clear inclusion and exclusion criteria, were included in this review. The studies included in this review were conducted in the last 10 years and researched the effectiveness of only topical therapies on female BC patients. The severity of RD starting at baseline 0 to endpoint was measured using the Radiation Therapy Oncology Group (RTOG) scale, and results show most patients experienced a RTOG score change of 0-1 or 0-2. A significant relationship between results obtained from 0-1 and 0-2 was shown (p < 0.00001). Results suggest Radioskin 1&2 cream is the most effective topical treatment for RD as 95% of patients experienced a RTOG score change of 0-1 compared to 5% experiencing 0-2. However, controlled treatments like general care and Aqua Cream seem to be the least effective, as 1.9% of patients administrating general care experienced a RTOG score change of 0-1 compared to 41.9% experiencing 0-2

B cell responses to a peptide epitope. X. Epitope selection in a primary response is thermodynamically regulated

We examine the etiological basis of hierarchical immunodominance of B cell epitopes on a multideterminant Ag. A model T-dependant immunogen, containing a single immunodominant B cell epitope, was used. The primary IgM response to this peptide included Abs directed against diverse determinants presented by the peptide. Interestingly, affinity of individual monomeric IgM Abs segregated around epitope recognized and was independent of their clonal origins. Furthermore, affinity of Abs directed against the immunodominant epitope were markedly higher than that of the alternate specificities. These studies suggested that the affinity of an epitope-specific primary response, and variations therein, may be determined by the chemical composition of epitope. This inference was supported by thermodynamic analyses of monomer IgM binding to Ag, which revealed that this interaction occurs at the expense of unfavorable entropy changes. Permissible binding required compensation by net enthalpic changes. Finally, the correlation between chemical composition of an epitope, the resultant affinity of the early primary humoral response, and its eventual influence on relative immunogenicity could be experimentally verified. This was achieved by examining the effect of various amino-terminal substitutions on immunogenicity of a, hitherto cryptic, amino-terminal determinant. Such experiments permitted delineation of a hierarchy of individual amino acid residues based on their influence; which correlated well with calculated Gibbs-free energy changes that individual residue side chains were expected to contribute in a binding interaction. Thus, maturation of a T-dependant humoral response is initiated by a step that is under thermodynamic control

B cell responses to a peptide epitope. VIII. Immune complex-mediated regulation of memory B cell generation within germinal centers

Using an in vivo reconstitution assay, we examine here the role of immune complexes in both formation of germinal centers (GC) and processes that occur subsequently within. The presence of Ag, as immune complexes, was found not to constitute a limiting requirement for the initiation of GC formation. No detrimental effect either on numbers or sizes of the resulting GC was observed when Ag-containing immune complexes were omitted during reconstitution. Thus, both recruitment and proliferation of Ag-activated B cells within GC appear not to be limited by Ag concentrations. In contrast, the presence of immune complexes was observed to be obligatory for the generation of Ag-specific memory B cells. This optimally required immune complexes to be constituted by IgG-class Abs with epitope specificities that were homologous to those of the GC B cells. The GC reaction was also found to be characterized by an enhancement of Ab specificity for the homologous epitope. Although some improvement in specificity was noted in recall responses from immune complex-deficient GC, the presence of appropriate immune complexes served to further optimize the outcome. Here again, isotype and epitope-specificity of the Ab constituent in immune complexes proved to be important

SYNTHESIS, CHARECTERIZATION AND ANTI-MICROBIAL ACTIVITY OF SUBSTITUTED 5-(5-SULFANYL-1,3,4-OXADIAZOL-2-YL)BENZENE- 1,2,3-TRIOL DERIVATIVES

A solution of propyl gallate(0.01 mol) in ethanol and hydrazine hydrate (0.01 mol) was refluxed for 4 hours. The excess solvent was distilled off under reduced pressure. The cooled residual mass was washed with distilled water. It was filtered and dried. The crude product was recrystallised from methanol to yield galloylhydrazide, Carbon disulfide (2 ml) was added drop wise to an ice cooled solution of KOH (2g) in ethanol (20 ml) containing the acid hydrazide 4 (0.02 mole), then the reaction mixture was stirred at room temperature 2h . After dilution with ethanol the solid precipitated was washed twice with ether. To the solid obtained (1 g), 10% KOH (20 ml) was added then the reaction mixture was refluxed for 4 hr, cooled, acidified with conc. HCl. The resulting solid was filtered washed with water, dried and crystallized. A mixture of (0.97g, 0.005mol) of 5-(5-sulfanyl- 1,3,4-oxadiazol-2-yl)benzene-1,2,3-triol and (0.005mol) of different aryl or alkyl&nbsp; halides were refluxed in 25ml of pyridine solution for 3.5 hours. The resultant mixture was cooled and poured into crushed ice. The solid mass is thus separated out was dried and recrystallized from ethanol. Synthesized derivatives purity were checked by TLC, Melting point &amp; characterized by FT-IR, Mass, NMR spectroscopic techniques. Synthesized derivatives were evaluated for anti-microbial activity. Keywords: Oxadiazole, Oxadiazole derivatives, Anti-microbial activity