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1.
Plast Reconstr Surg Glob Open ; 12(2): e5633, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38415103

RESUMEN

Background: Alveolar periosteoplasty during primary repair of cleft lip is still a topic of debate due to the fear exacerbating maxillary retrusion. The authors present their experience with early closure of alveolar clefts. The study aims to analyze gingivoperiosteoplasty (GPP) by comparing the use of locoregional flaps versus distant grafts for reconstruction of the lower layer of the primary palate cleft. Methods: Seventeen infants underwent 22 alveolar cleft repairs. After nasal floor repair by nasal mucoperiosteum, the oral layer was repaired by maxillary or gingival periosteal flaps in seven patients with alveolar clefts less than or equal to 6 mm wide, and tibial or pericranial periosteal grafts in 10 patients with wider clefts. At teenage years, crossbites in three flap-GPP and three graft-GPP patients were compared with nine older adolescents without primary GPP. Results: Alveolar clefts were perfectly sealed. Radiographs during the early 3 postoperative years showed new bone formation more posteriorly extended in patients who underwent graft-GPP. Teeth eruption and alveolar rigidity at the mixed dentition age eliminated the need for secondary bone grafting. The anterior crossbites in adolescent patients ranged between -2 and -14 mm; crossing was relatively smaller in patients with a younger age and without cleft palate. The mean crossbite was 7.2 mm in the six teenagers and 9.6 mm in the control cases. Conclusions: Graft-GPP may be a good alternative to flap-GPP, particularly for wide alveolar cleft repair. Maxillary retrusion is aggravated in patients with cleft palate and older age at assessment. GPP may not increase crossbite.

2.
Appl Opt ; 63(3): 762-771, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38294389

RESUMEN

In this work, the fixed right shift (FRS) code is utilized for the optical code division multiple access (OCDMA) technique in an underwater optical wireless communication (UOWC) system. Additionally, in this system, a 532 nm laser diode (LD) source is employed to generate optical signals. The investigation encompasses an analysis of five distinct Jerlov water types, each exhibiting diverse chlorophyll concentrations. The performance of the proposed system is evaluated when each channel that is assigned a unique FRS code sequence carries different data rates (2.5, 5, and 10 Gbps). Underwater (UW) ranges, bit error rate (BER), eye diagrams, and quality factor (Q-factor) are the performance metrics used to evaluate the system performance. The proposed UOWC-FRS/OCDMA system is simulated, and the obtained results show that the eye diagram openings close, the BER increases, and the Q-factor decreases as the data rate per each channel increases from 2.5 to 10 Gbps, and the attenuation of water becomes higher. Moreover, the lower attenuation values caused by the Jerlov type I (JI) waterbody allow each channel to carry 10 Gbps of data to propagate longer UW for a range of 35 m with a log(BER) ≤-6.33 and Q-factor greater than 4.9. On the other hand, at the same values of BER and Q-factor, the shortest ranges of 12 and 5.15 m are obtained for JII and JIII waters, respectively, where their attenuation coefficient values are 0.5297 (JII) and 1.8998 m -1 (JIII). Furthermore, as our model uses three channels, the overall achieved capacity is 3×10G b p s=30G b p s.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123759, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38198997

RESUMEN

A new series of coordinated metal (Fe(III), Co(II) and Cu(II)) and charge transfer complexes of Schiff base isonicotinic acid (2-hydroxy acetophenonylidene) hydrazide (L) have been synthesized. The ligand (L), its metals and CT complexes were characterized by UV-Vis spectra, FT-IR, 1HNMR and elemental analysis as well as conductance measurements. The pKa of L was determined in universal buffer solutions (20% v/v EtOH-H2O) with varying pH's values. The molar conductivity measurements prove the non-electrolytic nature of all metal complexes. Furthermore, the thermogravimetry (TG) and differential thermal analysis (DTA) of the synthesized complexes were carried out in the range of 30-1000 °C. In addition, interaction of (L) as an electron donor with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as π-type electron acceptor has been studied and characterized. The observed new band at 585 nm might be assigned as charge transfer (CT) absorption band. The electronic absorption spectrum of L-DDQ interaction is found to be dependent on time. The IR spectra of L with the coordinated metals and CT-complexes revealed new main IR bands, which strongly support the formation of complexes. The stoichiometry of the complexes was determined from photometric titration methods which are in accordance with the results of elemental analyses. The ratio were found to be 1:2 (metal:L) and 1:1 (L:DDQ). The spectra of L, its coordinated metals and CT complexes are fully discussed.

4.
Sci Rep ; 13(1): 18432, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891357

RESUMEN

Transform-domain audio watermarking systems are more robust than time-domain systems. However, the main weakness of these systems is their high computational cost, especially for long-duration audio signals. Therefore, they are not desirable for real-time security applications where speed is a critical factor. In this paper, we propose a fast watermarking system for audio signals operating in the hybrid transform domain formed by the fractional Charlier transform (FrCT) and the dual-tree complex wavelet transform (DTCWT). The central idea of the proposed algorithm is to parallelize the intensive and repetitive steps in the audio watermarking system and then implement them simultaneously on the available physical cores on an embedded systems cluster. In order to have a low power consumption and a low-cost cluster with a large number of physical cores, four Raspberry Pis 4B are used where the communication between them is ensured using the Message Passing Interface (MPI). The adopted Raspberry Pi cluster is also characterized by its portability and mobility, which are required in watermarking-based smart city applications. In addition to its resistance to any possible manipulation (intentional or unintentional), high payload capacity, and high imperceptibility, the proposed parallel system presents a temporal improvement of about 70%, 80%, and 90% using 4, 8, and 16 physical cores of the adopted cluster, respectively.

5.
Sci Rep ; 13(1): 17490, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37840064

RESUMEN

Hydroxyapatite (HA) can be used in odontology and orthopedic grafts to restore damaged bone due to its stable chemical characteristics, composition, and crystal structural affinity for human bone. A three-step hydrothermal method was used for the extraction of biogenic calcined HA from the buffalo waste bones at 700 °C (HA-700) and 1000 °C (HA-1000). Extracts were analyzed by thermogravimetric analysis, differential scanning calorimetry, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and in vivo examination of HA xenografts for femoral lesions in experimental rats. Crystallinity, purity, and morphology patterns showed that the HA main phase purity was 84.68% for HA-700 and 88.99% for HA-1000. Spherical HA nanoparticles were present for calcined HA-700 samples in the range 57-423 nm. Rats with critical bone lesions of 3 mm in diameter in the left femur treated with calcined HA-700 nanoparticles healed significantly (p < 0.001) faster than rats treated with HA-1000 or negative controls. These findings showed that spherical biogenic HA-700 NPs with a bud-like structure have the potential to stimulate both osteoconduction and bone remodeling, leading to greater bone formation potential in vivo. Thus, the calcined biogenic HA generated from buffalo waste bones may be a practical tool for biomedical applications.


Asunto(s)
Durapatita , Nanopartículas , Humanos , Animales , Ratas , Durapatita/química , Xenoinjertos , Huesos/diagnóstico por imagen , Nanopartículas/química , Osteogénesis , Difracción de Rayos X , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier
6.
J Pers Med ; 13(5)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37240918

RESUMEN

Full thickness cartilage defects in cases of knee osteoarthritis are challenging in nature and are difficult to treat. The implantation of three-dimensional (3D) biofabricated grafts into the defect site can be a promising biological one-stage solution for such lesions that can avoid different disadvantages of the alternative surgical treatment options. In this study, the short-term clinical outcome of a novel surgical technique that uses a 3D bioprinted micronized adipose tissue (MAT) graft for knee cartilage defects is assessed and the degree of incorporation of such graft types is evaluated via arthroscopic and radiological analyses. Ten patients received 3D bioprinted grafts consisting of MAT with an allogenic hyaline cartilage matrix on a mold of polycaprolactone, with or without adjunct high tibial osteotomy, and they were monitored until 12 months postoperatively. Clinical outcomes were examined with patient-reported scoring instruments that consisted of the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score and the Knee Injury and Osteoarthritis Outcome Score (KOOS). The graft incorporation was assessed using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. At 12 months follow-up, cartilage tissue biopsy samples were taken from patients and underwent histopathological examination. In the results, at final follow-up, the WOMAC and KOOS scores were 22.39 ± 7.7 and 79.16 ± 5.49, respectively. All scores were significantly increased at final follow-up (p < 0.0001). MOCART scores were also improved to a mean of 82.85 ± 11.49, 12 months after operation, and we observed a complete incorporation of the grafts with the surrounding cartilage. Together, this study suggests a novel regeneration technique for the treatment of knee osteoarthritis patients, with less rejection response and better efficacy.

7.
Nervenarzt ; 94(10): 934-943, 2023 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-37140605

RESUMEN

BACKGROUND: Malignant middle cerebral artery infarction is a potentially life-threatening disease. Decompressive hemicraniectomy constitutes an evidence-based treatment practice, especially in patients under 60 years of age; however, recommendations with respect to postoperative management and particularly duration of postoperative sedation lack standardization. OBJECTIVE: This survey study aimed to analyze the current situation of patients with malignant middle cerebral artery infarction following hemicraniectomy in the neurointensive care setting. MATERIAL AND METHODS: From 20 September 2021 to 31 October 2021, 43 members of the initiative of German neurointensive trial engagement (IGNITE) network were invited to participate in a standardized anonymous online survey. Descriptive data analysis was performed. RESULTS: Out of 43 centers 29 (67.4%) participated in the survey, including 24 university hospitals. Of the hospitals 21 have their own neurological intensive care unit. While 23.1% favored a standardized approach regarding postoperative sedation, the majority utilized individual criteria (e.g., intracranial pressure increase, weaning parameters, complications) to assess the need and duration. The timing of targeted extubation varied widely between hospitals (≤ 24 h 19.2%, ≤ 3 days in 30.8%, ≤ 5 days in 19.2%, > 5 days in 15.4%). Early tracheotomy (≤ 7 days) is performed in 19.2% and 80.8% of the centers aim for tracheotomy within 14 days. Hyperosmolar treatment is used on a regular basis in 53.9% and 22 centers (84.6%) agreed to participate in a clinical trial addressing the duration of postoperative sedation and ventilation. CONCLUSION: The results of this nationwide survey among neurointensive care units in Germany reflect a remarkable heterogeneity in the treatment practices of patients with malignant middle cerebral artery infarction undergoing hemicraniectomy, especially with respect to the duration of postoperative sedation and ventilation. A randomized trial in this matter seems warranted.


Asunto(s)
Craniectomía Descompresiva , Infarto de la Arteria Cerebral Media , Humanos , Infarto de la Arteria Cerebral Media/cirugía , Craniectomía Descompresiva/métodos , Encuestas y Cuestionarios , Hospitales Universitarios , Traqueotomía , Resultado del Tratamiento
8.
Sensors (Basel) ; 23(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37177567

RESUMEN

In the fireworks industry (FI), many accidents and explosions frequently happen due to human error (HE). Human factors (HFs) always play a dynamic role in the incidence of accidents in workplace environments. Preventing HE is a main challenge for safety and precautions in the FI. Clarifying the relationship between HFs can help in identifying the correlation between unsafe behaviors and influential factors in hazardous chemical warehouse accidents. This paper aims to investigate the impact of HFs that contribute to HE, which has caused FI disasters, explosions, and incidents in the past. This paper investigates why and how HEs contribute to the most severe accidents that occur while storing and using hazardous chemicals. The impact of fireworks and match industry disasters has motivated the planning of mitigation in this proposal. This analysis used machine learning (ML) and recommends an expert system (ES). There were many significant correlations between individual behaviors and the chance of HE to occur. This paper proposes an ML-based prediction model for fireworks and match work industries in Sivakasi, Tamil Nadu. For this study analysis, the questionnaire responses are reviewed for accuracy and coded from 500 participants from the fireworks and match industries in Tamil Nadu who were chosen to fill out a questionnaire. The Chief Inspectorate of Factories in Chennai and the Training Centre for Industrial Safety and Health in Sivakasi, Tamil Nadu, India, significantly contributed to the collection of accident datasets for the FI in Tamil Nadu, India. The data are analyzed and presented in the following categories based on this study's objectives: the effect of physical, psychological, and organizational factors. The output implemented by comparing ML models, support vector machine (SVM), random forest (RF), and Naïve Bayes (NB) accuracy is 86.45%, 91.6%, and 92.1%, respectively. Extreme Gradient Boosting (XGBoost) has the optimal classification accuracy of 94.41% of ML models. This research aims to create a new ES to mitigate HE risks in the fireworks and match work industries. The proposed ES reduces HE risk and improves workplace safety in unsafe, uncertain workplaces. Proper safety management systems (SMS) can prevent deaths and injuries such as fires and explosions.


Asunto(s)
Accidentes , Sustancias Peligrosas , Humanos , Teorema de Bayes , India , Aprendizaje Automático
9.
Appl Opt ; 62(1): 142-152, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36606859

RESUMEN

Currently, free space optics (FSO) transmission has gained attention due to its capability to deliver high data rates with a high level of security. In addition, using multiplexing techniques with FSO makes it capable of handling the excessive increase in traffic data and supporting the 5G and 6G wireless network requirements. Accordingly, in this paper, a novel, to the best of our knowledge, FSO system integrating three multiplexing techniques-orbital angular momentum (OAM) (four OAM beams are used) polarization-division multiplexing (two polarization states are used), and optical code division multiple access (four channels assigned with permutation vector codes are used)-is proposed. Additionally, the effects of rainy, foggy, dusty weather and the real weather for four different Indian cities that have different geographical locations are studied and investigated. The system performance is evaluated based on the bit error rate (BER), quality factor (Q-factor), maximum FSO range, and eye diagram opening. The simulation results show successful transmission of 320 Gbps overall capacity with a maximum achievable FSO range of 7 km under clear weather. On the other hand, the shortest FSO range of 0.105 km is achieved when there are heavy dust storms. As for the Indian cities, Srinagar (hilly area of India) achieves the shortest FSO link, which is 4.2 km while the largest range of 7 km is observed for Chennai city (coastal area of India). All these ranges are evaluated for a log(BER) value <-7. Consequently, this proposed transmission model is suggested for use in 6G applications of FSO communication systems.

10.
Saudi J Biol Sci ; 30(1): 103507, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36458096

RESUMEN

This study aimed to assess the impact of Moringa oleifera (M. oleifera) leaf extract against the poisoning of lead acetate; therefore, sixty mice were allocated into 4 groups with 15 in each, as G1) blank control, G2) supplied with 300 mg/kg body weight (BWT). M. oleifera extract, G3) supplied with 60 mg/kg BWT of lead acetate [Pb(C2H3O2)2], and G4) supplied with extract of M. oleifera + lead acetate. The liver enzymes were elevated post-treatment with Pb(C2H3O2)2, which then lowered to almost the normal level when M. oleifera was supplied to mice previously treated with Pb(C2H3O2)2. The values in (G3) decreased when compared with G1 (92.33 ± 12.99, 21.67 ± 2.91 and 98.00 ± 13.20 U/L, respectively. Also, the cholesterol and low-density lipoprotein levels were elevated post-supplementation with M. oleifera and Pb(C2H3O2)2. Pb(C2H3O2)2 improves the lipid profile, whereas M. oleifera pretreatment reduced cholesterol (CHOL), high density low cholesterol (HDL-c), and low-density low cholesterol (LDL-c) levels in animals fed Pb(C2H3O2)2. Pb(C2H3O2)2 elevates the total protein but lowers the total bilirubin and triglycerides post M. oleifera treatment and Pb(C2H3O2)2 when contrasted with G1. The protective effect of M. oleifera was caused by the fact that it lowered triglycerides (TG) and total bilirubin (TBIL) and raised total protein (TP). After administration of Pb(C2H3O2)2, the histological examination revealed alterations in the hepatocytes and kidneys of G3. Also, the liver and kidney cells in mice supplied with M. oleifera after Pb(C2H3O2)2 poisoning recovered. In conclusion, Pb is toxic, and the usage of M. oleifera partially enhances the negative impacts induced by Pb(C2H3O2)2.

11.
Bioengineering (Basel) ; 9(12)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36550994

RESUMEN

In this research, a one-dimensional (1D) photonic structure was employed to study the nature of both enamel and dentine teeth at the signal of 1.8 THz. A simple three layer one-dimensional crystal is chosen to avoid fabrication intricacy. The materials and methods for sample preparations are discussed. The principle of investigation of caries in the teeth relies on the amount of reflected signal from the structure. Similarly, reflectance is a function of refractive indices and thickness of each layer, the nature of both substrate and infiltrated materials, and the configuration of the structure. Apart from this, the fabrication process of one-dimensional structure and experimental set-up was proposed in this article. The numerical treatment is explained here to obtain reflectance, and subsequently, the output potential. Comparison studies on output potential between enamel and dentine are also shown through graphical representation. The output result in terms of milli-Volt (mV) were obtained at the output end and collected at the photodiode. Interesting results were also observed at the photodetector. For example; the output potential of the reflected signal is around 0.18 mV for both enamel and dentine teeth whereas the potential is more than 0.26 mV and 0.31 mV for caries in dentine and enamel, respectively. Finally, it was inferred that the nature of teeth pertaining to the caries in the enamel and dentine teeth can be investigated by identifying the amount of potential at the output end.

12.
Commun Biol ; 5(1): 934, 2022 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-36085302

RESUMEN

There is need for a reliable in vitro system that can accurately replicate the cardiac physiological environment for drug testing. The limited availability of human heart tissue culture systems has led to inaccurate interpretations of cardiac-related drug effects. Here, we developed a cardiac tissue culture model (CTCM) that can electro-mechanically stimulate heart slices with physiological stretches in systole and diastole during the cardiac cycle. After 12 days in culture, this approach partially improved the viability of heart slices but did not completely maintain their structural integrity. Therefore, following small molecule screening, we found that the incorporation of 100 nM tri-iodothyronine (T3) and 1 µM dexamethasone (Dex) into our culture media preserved the microscopic structure of the slices for 12 days. When combined with T3/Dex treatment, the CTCM system maintained the transcriptional profile, viability, metabolic activity, and structural integrity for 12 days at the same levels as the fresh heart tissue. Furthermore, overstretching the cardiac tissue induced cardiac hypertrophic signaling in culture, which provides a proof of concept for the ability of the CTCM to emulate cardiac stretch-induced hypertrophic conditions. In conclusion, CTCM can emulate cardiac physiology and pathophysiology in culture for an extended time, thereby enabling reliable drug screening.


Asunto(s)
Biomimética , Corazón , Cardiomegalia , Medios de Cultivo , Humanos , Sístole
13.
Opt Lett ; 47(11): 2887-2890, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35648956

RESUMEN

Optical space communication has been proven to be a reliable relay satellite transmission system. The difficulty that occurs in RF satellite communication (SatCom) can be alleviated by using free-space optical (FSO) or laser SatCom. In this work, we analyze a proposed laser downlink relay SatCom model with existing channel turbulence employing intensity modulation and direct detection (IM/DD), and amplify-and-forward (AF) technology and compare it with the optical direct link SatCom. Accounting for atmospheric attenuation and turbulence, the effect of model parameters such as zenith angle, receiver aperture radius, best number of optical ground stations (OGSs), and end-to-end operating wavelength on system performance is investigated for different OGS height scenarios. We provide exact closed-form expressions for the proposed model and optimize system performance by selecting the best number of OGSs using a selective diversity technique that can boost the system signal-to-noise (SNR) by up to 37 dB (99.9%).

14.
Opt Lett ; 47(9): 2133-2136, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35486742

RESUMEN

Visible light communication (VLC) has shown significant growth in recent years. VLC simultaneously offers illumination and communication. In VLC systems, dimming control is used to handle the lighting and energy consumption constraints. In this paper, a new, to the best of our knowledge, adaptive digital dimming optical-orthogonal frequency division multiplexing (ADDO-OFDM) based on pulse width modulation is proposed to combine enhanced asymmetrically clipped DC biased optical OFDM (EADO-OFDM) and negative EADO-OFDM (ENADO-OFDM). It exploits the performance benefits of EADO-OFDM and ENADO-OFDM. The proposed ADDO-OFDM controls the dimming level in a vast range with an acceptable bit error rate with a favorable data length.

15.
Water Sci Technol ; 84(12): 3833-3858, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34928847

RESUMEN

Water pollution is one of the problems that threaten humanity, and to confront it with only experimental procedures is not enough. It is necessary to integrate both practical methods and theoretical calculations to achieve decontamination with the most accurate interpretation. Hence, discussing the experimental mechanism study of Malachite Green (MG) dye adsorption with the help of the application of density functional theory (DFT) calculations is the main goal of this article. The experimental results affirmed that the preparation of γ-Al2O3 by precipitation method using (NH4)2CO3 improved the porosity, the surface capability, and the adsorbent capacities (qmax = 210 mg/g) at optimum condition compared with the previous studies. Kinetic and equilibrium studies showed that the adsorption follows the pseudo-second-order model and Freundlich isotherm model, respectively. Also, the calculated and observed thermodynamic parameters exerted positive values of ΔH° and ΔS°, which translates into an endothermic process with increasing disorder of the system. Theoretical calculations at DFT- B3LYP/6-31G (d,P) level of theory were calculated to show the selectivity of using the cationic form of MG in the experimental measurements to find the interaction mechanism. The electronic structure and intramolecular charge transfer of MG, its cationic form and the complex of MG-Al were investigated theoretically at the B3LYP/6-31 G (d,p) level of theory. The equilibrium geometries of MG, its cationic form and the complex of MG-Al were determined, and it was found that these geometries are non-planar. The EHOMO and ELUMO energies can be used to calculate the global properties; chemical hardness (η), softness (S) and electronegativity (χ). The calculated non-linear optical parameters (NLO) of the studied compounds, the electronic dipole moment (µ), first-order hyperpolarizability (ß), the hyper-Rayleigh scattering (ßHRS) and the depolarization ratio (DR), showed promising optical properties. Finally, the computational and the experimental results indicated that the adsorption efficiency of MG from wastewater was directly associated with the dye electrophilicity power.


Asunto(s)
Colorantes de Rosanilina , Aguas Residuales , Adsorción , Porosidad
16.
Opt Quantum Electron ; 53(11): 625, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34658489

RESUMEN

To handle the massive high-speed internet traffic, free space optics (FSO) or single-mode fiber (SMF) based fiber optic communication is being used everywhere across the world. These technologies are capable of providing huge bandwidth and transmitting the data at very high speed with low energy consumption. FSO is a very convenient technology to quickly expand the legacy network in the adverse geographical areas. However, its link performance is highly dependent of inconsistent weather conditions. SMF based fiber optic link has a very low loss and its performance is almost independent on the weather conditions. Though, the installation and maintenance of fibers are quite complex and costly. Individually, FSO or SMF links have their limitations and have to be integrated to leverage their benefits. In this paper, we integrated FSO/SMF links and compared the performance of the proposed architecture which is capable of providing high-speed dual-rate data transmission. The proposed architecture transmits data over either FSO or SMF or both links simultaneously and has 100% more reliability against any one of the link failures. In case of operational link failure (FSO/SMF), data may be switched to the alternative working link (SMF/FSO), simply by tuning the transmitted signal by 50 GHz. The proposed architecture is also reliable against the optical line terminal transceiver (TRx) failure as each user located in the network can be served by two transceivers (1 Gbps and 10 Gbps). The proposed architecture also supports the wavelength division multiplexing overlay transmission for broadcasting the common signal to all the available users in the networks. The architecture reduces ~ 27% of the energy consumption by utilizing the appropriate link of hybrid architecture and TRx according to weather conditions and traffic load. The integrated architecture looks attractive for providing energy-efficient, high speed, and reliable internet coverage to the areas where there is a difficulty of laying fibers and has frequent fiber faults. The architecture is useful for strengthening and boosting rural and urban development.

17.
Appl Opt ; 60(24): 7279-7289, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34613016

RESUMEN

The preinstalled white light emitting diodes (WLEDs) inside buildings can be exploited as an optical source in visible light communications (VLC) motivated by high optical efficiency and low cost. One of the main challenges for VLC is LED nonlinear distortion, which has a detrimental effect on system performance. Estimation and compensation of the LED nonlinear behavior can be accomplished using predistortion or postdistortion techniques. Three compensation techniques are adopted to mitigate the effect of LED nonlinearity on layered asymmetrically clipped optical, orthogonal frequency division multiplexing. Their performance and efficiency are discussed and compared with the aid of error vector magnitude and bit error rate (BER) in an additive white Gaussian noise channel. The obtained results reveal that polynomial-based predistorters and postdistorters can overcome the LED nonlinear behavior with extra SNR of only 0.25 dB at BER of 10-3. Furthermore, the look-up-table-based predistorter can provide the same BER with lower SNR penalty than the previous two systems.

18.
CVIR Endovasc ; 4(1): 60, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34269932

RESUMEN

PURPOSE: Visceral artery pseudoaneurysms (VAPAs) are uncommon in clinical practice but may have serious clinical outcomes up to death. Endovascular management is a safe effective alternative option to traditional surgical procedures. This study assesses the outcome of different embolic materials and techniques used in the endovascular management of VAPAs. MATERIALS AND METHODS: This is a two-center retrospective analysis of endovascular embolisation of 46 VAPAs, with a mean pseudoaneurysm size of 13 ± 11.35 mm, that were urgently managed between July 2018 and March 2020. Patients' presentations were GIT hemorrhage, intrabdominal hemorrhage, hematuria, and abdominal pain in 34.78%, 30.43%, 23.91%, and 10.87% respectively. Management using coils only was done in 28/46 patients (60.87%), NBCA glue only in 16/46 patients (34.78%), combined coils and NBCA glue in 1/46 patient (2.17%), and Amplatzer plugs only in 1 patient (2.17%). The management techniques were sac packing in 9/46 patients (19.57%), inflow occlusion in 28/46 patients (60.87%) and trapping in 9/46 patients (19.57%). All patients were followed-up for 1 year after the procedure. RESULTS: The overall clinical success and periprocedural complication rates were 93.48%, and 15.22% respectively, and 30-day mortality was zero. Clinical success was 92.86% in the coil subgroup (n = 28), and 93.75% in the NBCA glue subgroup (n = 16). The technical success rate was 100%. Effectiveness of the procedures during the follow-up was 97.83%. Target lesion re-intervention rate was 2.17%. CONCLUSION: Transarterial embolisation can provide high technical and clinical success rates with low periprocedural complication and re-intervention rates, as well as satisfactory procedure effectiveness in the management of VAPAs.

19.
J Genet Eng Biotechnol ; 19(1): 109, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34322776

RESUMEN

BACKGROUND: Insulin-like growth factor-1 (IGF-1) is required for normal intrauterine and postnatal growth, and this action is mediated through IGF1 receptor (IGF1R). IGF1R copy number variants (CNVs) can cause pre- and postnatal growth restriction, affecting an individual's height. In this study, we used multiplex ligation-dependent probe amplification (MLPA) to detect CNVs in IGF1R, IGFALS, and IGFBP3 genes in the diagnostic workup of short stature for 40 Egyptian children with short stature. RESULTS: We detected a heterozygous deletion of IGF1R (exons 4 through 21) in 1 out of the 40 studied children (2.5%). Meanwhile, we did not detect any CNVs in either IGFALS or IGFBP3. CONCLUSION: The diagnostic workup of short stature using MLPA for CNVs of IGF1R and other recognized height-related genes, such as SHOX and GH, in non-syndromic short stature children can be a fast and inexpensive diagnostic tool to recognize a subcategory of patients in which growth hormone treatment can be considered.

20.
J Surg Case Rep ; 2021(4): rjab089, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33897996

RESUMEN

Post-thyroidectomy bleeding is a fortunately rare but potentially life-threatening complication that may increase postoperative morbidity and hospital stay. In this case series, we demonstrate the relation between the measurement of neck circumference and haemorrhage following thyroid surgery and the value of this measurement in predicting post-thyroidectomy haemorrhage. Currently, there is no simple and reliable method available for the early detection of post-thyroidectomy bleeding. Continuous pressure measurement could be a potential tool for the early detection of haemorrhage but is invasive, and more data are required to recommend threshold values for revision surgery. Early recognition and prompt surgical intervention are key to the management of cervical haematoma. Measurement of the neck circumference is a valuable adjunct tool in the early recognition of post-thyroidectomy bleeding. In this case series, we concluded that a 4-cm increase in neck circumference may trigger the clinical decision for cervical exploration.

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