scholarly journals Some Contributions for Antenna 3D Far Field Characterization at Terahertz

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1438
Author(s):  
Laurent Le Coq ◽  
Nicolas Mézières ◽  
Paul Leroy ◽  
Benjamin Fuchs
Keyword(s):  
Three Dimensional ◽  
Far Field ◽  
Compact Antenna ◽  
Field Patterns ◽  
Millimeter Wave Range ◽  
Before And After ◽  
Wave Range ◽  
Terahertz Frequencies ◽  
The Impact

The three-dimensional (3D) characterization of antenna far field patterns at terahertz frequencies is addressed. This task is challenging, because the phase of the electric field is difficult to measure accurately and reliably. From the sub-millimeter wave range, the small wavelength indeed significantly increases the impact of mechanical and electrical errors. Models and procedures to estimate these errors are proposed to mitigate their effects. The 3D far field patterns of a circularly polarized horn measured at 300 GHz and a multibeam pillbox antenna at 270 GHz are shown. The agreement between the 3D measurements and the two-dimensional (2D) patterns of reference as well as the radiated pattern before and after correction demonstrates the interest of the proposed approach and experimentally validate the proposed error estimation procedures. The methodology can be applied to direct far field measurement facilities as well as compact antenna test ranges.

scholarly journals Importance of physiotherapy/nursing multidisciplinary integration about update newborn position in the neonatal intensive care unit

2015 ◽  
Vol 28 (3) ◽  
pp. 437-445 ◽  
Author(s):  
Vanessa da Silva Neves Moreira Arakaki ◽  
Alana Monteiro de Oliveira ◽  
Trícia Bogossian ◽  
Viviane Saraiva de Almeida ◽  
Gustavo Dias da Silva ◽  
...  
Keyword(s):  
Intensive Care ◽  
Neonatal Intensive Care ◽  
Physical Therapist ◽  
Body Position ◽  
Effective Care ◽  
Before And After ◽  
Student’S T ◽  
The Impact ◽  
Clinical Stability

AbstractIntroduction The high-risk newborns may require long periods of hospitalization until they reach clinical stability for hospital discharge. Avoiding babies to be in only one body position may be an effective way to cause respiratory and neuro-psycho-motor benefits, comfort and preventing pressure ulcers.Objectives This study investigated the impact of physiotherapy/nursing integration in update on body positioning of the newborn in the Neonatal Intensive Care Unit.Methods A questionnaire was administered to nurses and nursing technicians of the neonatal unit of Maternity School of UFRJ and nurses of the Advanced Course in Neonatal Nursing from the same institution. Two classes were taught by the physical therapist of the sector and the questions answered before and after these lessons. It was also a brief characterization of professional participants of the study. We used the Student's t test to compare the correct answers before (PRE) and after (POST) the classes, considering p < 0.05.Results There was a significant increase in the degree of knowledge of nurses and nursing technicians when compared the responses before (nurses: 68.8%; technicians: 70.1%) and after classes (nurses: 78.4 %; technicians: 88.9%). The nurses were less than five years of graduated (45%) and little time of professional experience in neonatology (60%). Forty-seven percent of technicians had less than five years of training and 82% had less than 10 years of experience.Conclusion The use of training by the nursing staff was significant, showing the importance of multidisciplinary approach and the integration of knowledge in the search for a humanized and effective care.

scholarly journals Susceptibility of protein therapeutics to spontaneous chemical modifications by oxidation, cyclization, and elimination reactions

Amino Acids ◽  
2019 ◽  
Vol 51 (10-12) ◽  
pp. 1409-1431 ◽  
Author(s):  
Luigi Grassi ◽  
Chiara Cabrele
Keyword(s):  
Small Molecules ◽  
Three Dimensional ◽  
Drug Market ◽  
Structure And Function ◽  
Dimensional Structure ◽  
Chemical Modifications ◽  
Small Molecule Drugs ◽  
And Function ◽  
The Impact

Abstract Peptides and proteins are preponderantly emerging in the drug market, as shown by the increasing number of biopharmaceutics already approved or under development. Biomolecules like recombinant monoclonal antibodies have high therapeutic efficacy and offer a valuable alternative to small-molecule drugs. However, due to their complex three-dimensional structure and the presence of many functional groups, the occurrence of spontaneous conformational and chemical changes is much higher for peptides and proteins than for small molecules. The characterization of biotherapeutics with modern and sophisticated analytical methods has revealed the presence of contaminants that mainly arise from oxidation- and elimination-prone amino-acid side chains. This review focuses on protein chemical modifications that may take place during storage due to (1) oxidation (methionine, cysteine, histidine, tyrosine, tryptophan, and phenylalanine), (2) intra- and inter-residue cyclization (aspartic and glutamic acid, asparagine, glutamine, N-terminal dipeptidyl motifs), and (3) β-elimination (serine, threonine, cysteine, cystine) reactions. It also includes some examples of the impact of such modifications on protein structure and function.

scholarly journals The impact of contrast-enhanced spectral mammogram (CESM) and three-dimensional breast ultrasound (3DUS) on the characterization of the disease extend in cancer patients

2018 ◽  
pp. 20170977 ◽  
Author(s):  
Maha Hussien Helal ◽  
Sahar Mahmoud Mansour ◽  
Lamia Adel Salaleldin ◽  
Basma Mohamed Alkalaawy ◽  
Dorria Saleh Salem ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Three Dimensional ◽  
Breast Ultrasound ◽  
Contrast Enhanced ◽  
The Impact

scholarly journals Expression, purification and crystallization of a protein resulting from the inversion of the amino-acid sequence of a helical bundle

2017 ◽  
Vol 73 (1) ◽  
pp. 51-53
Author(s):  
Aikaterini Kefala ◽  
Dina Kotsifaki ◽  
Mary Providaki ◽  
Maria Amprazi ◽  
Michael Kokkinidis
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Three Dimensional ◽  
Unfolded Proteins ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Helical Bundle ◽  
Sequence Inversion ◽  
The Impact

Earlier studies have found that the occurrence of inverse sequence identity in proteins is not indicative of three-dimensional similarity, but rather leads to different folds or unfolded proteins. Short helices, however, frequently keep their conformations when their sequences are inverted. To explore the impact of sequence inversion on long helices, revRM6, with the inverse amino-acid sequence relative to RM6, a highly stable variant of the ColE1 Rop protein, was engineered. RM6 is a highly regular four-α-helical bundle that serves as a model system for protein-folding studies. Here, the crystallization and preliminary crystallographic characterization of revRM6 are reported. The protein was overexpressed inEscherichia coli, purified to homogeneity and crystallized. The crystals belonged to space groupP41212, with unit-cell parametersa=b= 44.98,c= 159.74 Å, and diffracted to a resolution of 3.45 Å.

scholarly journals MR ENTEROGRAPHY: AN EMERGENT TECHNIQUE FOR CHARACTERIZATION OF SMALL BOWEL LESIONS IN ONCOLOGICAL AND NON-ONCOLOGY DISEASES

2018 ◽  
Vol 4 (4) ◽  
Author(s):  
Waqas Ahmad ◽  
Iram Zaheer ◽  
Imran Khalid Niazi ◽  
Khurram Aftab Mufti
Keyword(s):  
Small Bowel ◽  
Imaging Technique ◽  
Contrast Material ◽  
Three Dimensional ◽  
Mr Enterography ◽  
Breath Hold ◽  
Diffusion Weighted Images ◽  
Before And After ◽  
Computed Tomography Enterography

Small bowel is not easily accessed by endoscope and diagnosis of its pathology relies on clinical assessment and imaging. Traditional contrast studies have the disadvantage of not including the mural and extramural details. This is best seen with magnetic resonance enterography (MRE) which is rapidly replacing computed tomography enterography due to better soft tissue resolution and lack of ionizing radiation. Comprehensive MRE requires axial and coronal T1- and T2-WI, high-resolution diffusion-weighted images, fat-suppressed three-dimensional T1-W breath-hold gradient-echo images of the abdomen, and pelvis before and after intravenous gadolinium-based contrast material administration. MRE is the preferred imaging technique for small bowel pathology due to its ability to show mural and extramural details which allow differentiation in acute, active, and chronicity of changes. Being radiation free, there is no age limitation for its use.

scholarly journals Using AlphaFold to predict the impact of single mutations on protein stability and function

2021 ◽  
Author(s):  
Marina A Pak ◽  
Karina A Markhieva ◽  
Mariia S Novikova ◽  
Dmitry S Petrov ◽  
Ilya S Vorobyev ◽  
...  
Keyword(s):  
Protein Folding ◽  
Protein Stability ◽  
Structure Prediction ◽  
Large Scale ◽  
3D Structure ◽  
Three Dimensional ◽  
Single Mutation ◽  
Before And After ◽  
And Function ◽  
The Impact

AlphaFold changed the field of structural biology by achieving three-dimensional (3D) structure prediction from protein sequence at experimental quality. The astounding success even led to claims that the protein folding problem is "solved". However, protein folding problem is more than just structure prediction from sequence. Presently, it is unknown if the AlphaFold-triggered revolution could help to solve other problems related to protein folding. Here we assay the ability of AlphaFold to predict the impact of single mutations on protein stability (ΔΔG) and function. To study the question we extracted metrics from AlphaFold predictions before and after single mutation in a protein and correlated the predicted change with the experimentally known ΔΔG values. Additionally, we correlated the AlphaFold predictions on the impact of a single mutation on structure with a large scale dataset of single mutations in GFP with the experimentally assayed levels of fluorescence. We found a very weak or no correlation between AlphaFold output metrics and change of protein stability or fluorescence. Our results imply that AlphaFold cannot be immediately applied to other problems or applications in protein folding.

scholarly journals Super Secondary Structures of Proteins with Post-Translational Modifications in Colon Cancer

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3144
Author(s):  
Dmitry Tikhonov ◽  
Liudmila Kulikova ◽  
Arthur Kopylov ◽  
Kristina Malsagova ◽  
Alexander Stepanov ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Control Cell ◽  
Three Dimensional ◽  
Vitamin D Binding Protein ◽  
High Throughput Analysis ◽  
Post Translational Modifications ◽  
New Strategy ◽  
The Impact ◽  
Identification And Characterization

New advances in protein post-translational modifications (PTMs) have revealed a complex layer of regulatory mechanisms through which PTMs control cell signaling and metabolic pathways, contributing to the diverse metabolic phenotypes found in cancer. Using conformational templates and the three-dimensional (3D) environment investigation of proteins in patients with colorectal cancer, it was demonstrated that most PTMs (phosphorylation, acetylation, and ubiquitination) are localized in the supersecondary structures (helical pairs). We showed that such helical pairs are represented on the outer surface of protein molecules and characterized by a largely accessible area for the surrounding solvent. Most promising and meaningful modifications were observed on the surface of vitamin D-binding protein (VDBP), complement C4-A (CO4A), X-ray repair cross-complementing protein 6 (XRCC6), Plasma protease C1 inhibitor (IC1), and albumin (ALBU), which are related to colorectal cancer developing. Based on the presented data, we propose the impact of the observed modifications in immune response, inflammatory reaction, regulation of cell migration, and promotion of tumor growth. Here, we suggest a computational approach in which high-throughput analysis for identification and characterization of PTM signature, associated with cancer metabolic reprograming, can be improved to prognostic value and bring a new strategy to the targeted therapy.

Dry Effect of Cementitious Materials on Testing Results of X-Ray CT

2012 ◽  
Vol 450-451 ◽  
pp. 187-192 ◽  
Author(s):  
Jian De Han ◽  
Wei Sun ◽  
Gang Hua Pan
Keyword(s):  
Cement Paste ◽  
Three Dimensional ◽  
Cementitious Materials ◽  
Drying Process ◽  
X Ray ◽  
Before And After ◽  
X Ray Computed ◽  
The Mean ◽  
The Impact ◽  
Gray Values

In this study three-dimensional X-ray computed tomography (X-ray CT) is used to investigate the testing results differences of cement paste and mortar before and after drying. It can be found that the mean gray values of paste and mortar before drying are bigger than after drying, and the impact of drying on cement paste is more serious than mortar. In addition, the porosity of non-drying cement paste and mortar is 1.10% and 0.43%, while that of drying cement paste and mortar is 1.55% and 0.70%, respectively. So, the porosity of paste and mortar markedly increases after drying process. The numbers of pores of paste and mortar sharply increase after drying process in particular between 0.01mm3 and 0.1mm3. The impact of drying on smaller pores is more serious than bigger pores.

THE GEOMETRICAL CHARACTERIZATION OF NEURAL ACTIVITY DISPLAYS A SENSITIVITY TO CONVULSANTS

1991 ◽  
Vol 01 (01) ◽  
pp. 253-259 ◽  
Author(s):  
I. D. ZIMMERMAN ◽  
P. E. RAPP ◽  
A. I. MEES
Keyword(s):  
Interspike Interval ◽  
Three Dimensional ◽  
Interval Data ◽  
Time Intervals ◽  
Geometrical Characterization ◽  
Single Nerve ◽  
Before And After ◽  
The Mean ◽  
Standard Techniques

Direct application of a drop of penicillin to the brain's surface can elicit brain electrical activity similar to that seen in some forms of epilepsy. The procedure has therefore become one of the standard techniques in the experimental investigation of epilepsy. The time intervals between action potentials, called the interspike intervals, were measured from single nerve cells in the cerebral cortex of the rat before and after local administration of penicillin. The resulting interspike interval data were examined by elementary statistical procedures and by embedding the data in two- and three-dimensional spaces. The mean interspike interval did not change significantly in response to penicillin. In contrast, the geometrical characterization displayed a dramatic sensitivity to the drug.

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