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1.
Entropy (Basel) ; 25(8)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37628175

RESUMEN

The general delay Hopfield neural network is studied. We consider the case of time-varying delay, continuously distributed delays, time-varying coefficients, and a special type of a Riemann-Liouville fractional derivative (GRLFD) with an exponential kernel. The kernels of the fractional integral and the fractional derivative in this paper are Sonine kernels and satisfy the first and the second fundamental theorems in calculus. The presence of delays and GRLFD in the model require a special type of initial condition. The applied GRLFD also requires a special definition of the equilibrium of the model. A constant equilibrium of the model is defined. An inequality for Lyapunov type of convex functions with the applied GRLFD is proved. It is combined with the Razumikhin method to study stability properties of the equilibrium of the model. As a partial case we apply quadratic Lyapunov functions. We prove some comparison results for Lyapunov function connected deeply with the applied GRLFD and use them to obtain exponential bounds of the solutions. These bounds are satisfied for intervals excluding the initial time. Also, the convergence of any solution of the model to the equilibrium at infinity is proved. An example illustrating the importance of our theoretical results is also included.

2.
Arch Gynecol Obstet ; 306(4): 1321-1327, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35821525

RESUMEN

PURPOSE: To determine if blastocyst trophectoderm biopsy for PGT-A is associated with an increased rate of live birth per embryo in good prognosis IVF patients at a single center. METHODS: We performed a retrospective cohort study of good prognosis embryo transfer cycles at a single center from 1/1/2017 to 12/31/2019. We evaluated the rate of live birth per embryo with and without PGT-A for transfer of embryos in two groups of good prognosis patients: embryos from donor oocytes and embryos from autologous oocytes with maternal age less than 35 years at oocyte retrieval. Two-sided Fisher's exact tests were used for comparisons between groups. RESULTS: After transfer of embryos created from donor oocytes the live birth rate per euploid embryo was 70.6% (24/34) compared to 34.3% (35/102) for untested embryos for a rate difference of 36.3% (95% CI 18.4-54.1%, p < 0.01). After transfer of embryos created from autologous oocytes with maternal age less than 35 years at oocyte retrieval the live birth rate per euploid embryo was 70.0% (49/70) compared to 52.5% (53/101) for untested embryos for a rate difference of 17.5% (95% CI 3.0-32.0%, p = 0.03). CONCLUSIONS: In good prognosis patients at our center the live birth rate per euploid blastocyst was higher than for untested blastocysts.


Asunto(s)
Tasa de Natalidad , Diagnóstico Preimplantación , Aneuploidia , Biopsia , Blastocisto/patología , Femenino , Fertilización In Vitro , Humanos , Nacimiento Vivo , Embarazo , Pronóstico , Estudios Retrospectivos
3.
Entropy (Basel) ; 24(3)2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-35327883

RESUMEN

A model of gene regulatory networks with generalized proportional Caputo fractional derivatives is set up, and stability properties are studied. Initially, some properties of absolute value Lyapunov functions and quadratic Lyapunov functions are discussed, and also, their application to fractional order systems and the advantage of quadratic functions are pointed out. The equilibrium of the generalized proportional Caputo fractional model and its generalized exponential stability are defined, and sufficient conditions for the generalized exponential stability and asymptotic stability of the equilibrium are obtained. As a special case, the stability of the equilibrium of the Caputo fractional model is discussed. Several examples are provided to illustrate our theoretical results and the influence of the type of fractional derivative on the stability behavior of the equilibrium.

4.
BMC Pregnancy Childbirth ; 21(1): 651, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34560839

RESUMEN

BACKGROUND: Diabetes Mellitus (DM) is a major cause of maternal, fetal, and neonatal morbidities. Our objective was to estimate the effect of both pre-pregnancy and gestational DM on the growth parameters of newborns in the Qatari population. METHODS: In this population-based cohort study, we compared the data of neonates born to Qatari women with both pre-pregnancy and gestational diabetes mellitus in 2017 with neonates of healthy non-diabetic Qatari women. RESULTS: Out of a total of 17020 live births in 2017, 5195 newborns were born to Qatari women. Of these, 1260 were born to women with GDM, 152 were born to women with pre-pregnancy DM and 3783 neonates were born to healthy non-diabetic (control) women. The prevalence of GDM in the Qatari population in 2017 was 24.25%. HbA1C% before delivery was significantly higher in women with pre-pregnancy DM (mean 6.19 ± 1.15) compared to those with GDM (mean 5.28 ± 0.43) (P <0.0001). The mean birth weight in grams was 3066.01 ± 603.42 in the control group compared to 3156.73 ± 577.88 in infants born to women with GDM and 3048.78 ± 677.98 in infants born to women with pre-pregnancy DM (P <0.0001). There was no statistically significant difference regarding the mean length (P= 0.080), head circumference (P= 0.514), and rate of major congenital malformations (P= 0.211). Macrosomia (Birth weight > 4000 gm) was observed in 2.7% of the control group compared to 4.8% in infants born to women with GDM, and 4.6% in infants born to women with pre-pregnancy DM (P= 0.001). Multivariate logistic regression analysis demonstrated that higher maternal age (adjusted OR 2.21, 95% CI 1.93, 2.52, P<0.0001), obesity before pregnancy (adjusted OR 1.71, 95% CI 1.30, 2.23, P<0.0001), type of delivery C-section (adjusted OR 1.25, 95% CI 1.09, 1.44, P=0.002), and body weight to gestational age LGA (adjusted OR 2.30, 95% CI 1.64, 2.34, P<0.0001) were significantly associated with increased risk of GDM. CONCLUSION: Despite the multi-disciplinary antenatal diabetic care management, there is still an increased birth weight and an increased prevalence of macrosomia among the infants of diabetic mothers. More efforts should be addressed to improve the known modifiable factors such as women's adherence to the diabetic control program. Furthermore, pre-pregnancy BMI was found to be significantly associated with gestational DM, and this is a factor that can be addressed during pre-conceptional counseling.


Asunto(s)
Diabetes Mellitus/epidemiología , Diabetes Gestacional/epidemiología , Recién Nacido/crecimiento & desarrollo , Embarazo en Diabéticas/epidemiología , Adulto , Peso al Nacer , Índice de Masa Corporal , Cesárea/estadística & datos numéricos , Estudios de Cohortes , Anomalías Congénitas/epidemiología , Estudios Transversales , Femenino , Macrosomía Fetal/epidemiología , Edad Gestacional , Hemoglobina Glucada , Humanos , Masculino , Edad Materna , Embarazo , Qatar/epidemiología , Estudios Retrospectivos
5.
Cardiol Young ; 31(3): 358-370, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33191897

RESUMEN

OBJECTIVES: Ductal stents, right ventricular outflow tract stents, and aortopulmonary shunts are used to palliate newborns and infants with reduced pulmonary blood flow. Current long-term outcomes of these palliations from resource-restricted countries are unknown. METHODS: This single-centre, retrospective, observational study analysed the technical success, immediate and late mortality, re-interventions, and length of palliation in infants ≤5 kg who underwent aortopulmonary shunts, ductal, and pulmonary outflow stents. Patients were grouped by their anatomy. RESULTS: There were 69 infants who underwent one of the palliations. Technical success was 90% for aortopulmonary shunts (n = 10), 91% for pulmonary outflow stents (n = 11) and 100% for ductal stents (n = 48). Early mortality within 30 days in 12/69 patients was observed in 20% after shunts, 9% after pulmonary outflow stents, and 19% after ductal stents. Late mortality in 11 patients was seen in 20% after shunts, 18% after outflow stents, and 15% after ductal stents. Seven patients needed re-interventions; two following shunts, one following outflow stent, and four following ductal stents for hypoxia. Among the anatomical groups, 10/12 patients with pulmonary atresia, intact ventricular septum survived after valvotomy and ductal stenting. Survival to Glenn shunt after ductal stent for pulmonary atresia, intact ventricular septum and diminutive right ventricle was very low in two out of eight patients, but very good (100%) for other univentricular hearts. Among 35 patients with biventricular lesions, 22 survived to the next stage. CONCLUSIONS: Cyanotic infants, despite undergoing technically successful palliation had a high inter-stage mortality irrespective of the type of palliation. Duct stenting in univentricular hearts and in pulmonary atresia with an intact ventricular septum and adequate sized right ventricle tended to have low mortality and better long-term outcome. Completion of biventricular repair after palliation was achieved only in 63% of patients, reflecting unique challenges in developing countries despite advances in intensive care and interventions.


Asunto(s)
Cardiopatías Congénitas , Atresia Pulmonar , Cateterismo Cardíaco , Países en Desarrollo , Cardiopatías Congénitas/cirugía , Humanos , Lactante , Recién Nacido , Cuidados Paliativos , Atresia Pulmonar/cirugía , Estudios Retrospectivos , Stents , Resultado del Tratamiento
6.
J Craniofac Surg ; 32(5): 1955-1965, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34319684

RESUMEN

ABSTRACT: Conditions that affect dental and periodontal structures receive sparse coverage in the plastic surgery literature, yet a working knowledge of this subject matter is important in certain areas of clinical practice and a fundamental understanding is part of plastic surgery competency tested on the in-service and written board examinations. This 4-part series was written to provide plastic surgeons with a working knowledge of dental topics that may be relevant to their clinical practice. This section, Part IV, covers common dental cyst and tumors of the jaw.


Asunto(s)
Quistes , Neoplasias Maxilomandibulares , Procedimientos de Cirugía Plástica , Cirujanos , Cirugía Plástica , Humanos , Neoplasias Maxilomandibulares/cirugía
7.
Entropy (Basel) ; 23(4)2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33920402

RESUMEN

As an effective tool to unify discrete and continuous analysis, time scale calculus have been widely applied to study dynamic systems in both theoretical and practical aspects. In addition to such a classical role of unification, the dynamic equations on time scales have their own unique features which the difference and differential equations do not possess and these advantages have been highlighted in describing some complicated dynamical behavior in the hybrid time process. In this review article, we conduct a survey of abstract analysis and applied dynamic equations on hybrid time scales, some recent main results and the related developments on hybrid time scales will be reported and the future research related to this research field is discussed. The results presented in this article can be extended and generalized to study both pure mathematical analysis and real applications such as mathematical physics, biological dynamical models and neural networks, etc.

8.
Entropy (Basel) ; 23(2)2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33498158

RESUMEN

The objective of this paper is to study oscillation of fourth-order neutral differential equation. By using Riccati substitution and comparison technique, new oscillation conditions are obtained which insure that all solutions of the studied equation are oscillatory. Our results complement some known results for neutral differential equations. An illustrative example is included.

9.
Entropy (Basel) ; 23(7)2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34356412

RESUMEN

In this work, we establish some integral inequalities involving metrics. Moreover, some applications to partial metric spaces are given. Our results are extension of previous obtained metric inequalities in the discrete case.

10.
Entropy (Basel) ; 23(8)2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34441226

RESUMEN

This research article is dedicated to solving fractional-order parabolic equations using an innovative analytical technique. The Adomian decomposition method is well supported by natural transform to establish closed form solutions for targeted problems. The procedure is simple, attractive and is preferred over other methods because it provides a closed form solution for the given problems. The solution graphs are plotted for both integer and fractional-order, which shows that the obtained results are in good contact with the exact solution of the problems. It is also observed that the solution of fractional-order problems are convergent to the solution of integer-order problem. In conclusion, the current technique is an accurate and straightforward approximate method that can be applied to solve other fractional-order partial differential equations.

11.
J Food Sci Technol ; 57(8): 3040-3050, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32624606

RESUMEN

This work explores the efficacy and potential of four different blends of essential oils as bio-preservative for enhancement of shelf life of emulsion based ready-to-eat chicken sausages. Pre-optimized levels of four different blends of essential oils: 0.25% each of B-1, B-2, B-3 and 0.125% of B-4, were tried in the chicken sausages. Four different treatments along with control were then aerobically packaged and stored under refrigerated (4 ± 1 °C) conditions. An increase in pH and TBARS value was found to be significantly lower in the case of B-2 products. Significantly higher values for DPPH activity (% inhibition) and total phenolic content (µg/g) were also observed for B-2 products which indicated that B-2 products had better oxidative stability. Further, B-1 and B-2 products were observed with significantly lower microbial count; however, B-4 products received slightly higher sensory scores than B-2. It was found that B-1, 2 and 3 (each at 0.25%) and B-4 (0.125%) enhanced the shelf life of chicken sausages by 13-14 days, 16-17 days, 10-11 days and 6-7 days, respectively under refrigerated (4 ± 1 °C) storage.

12.
Crit Care Nurs Q ; 41(4): 413-425, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30153186

RESUMEN

Intra-hospital transport (IHT) of intensive care unit (ICU) patients is associated with a 30% to 60% incidence of adverse events (AEs). This prospective observational study collected data from 200 patient transports from a 24-bed cardiovascular intensive care unit (ICU) between July 2017 and December 2017. Phase 1 of the study focused on identifying and correcting deficiencies in nurses' knowledge regarding IHT. Phase 2 observed the occurrence and type of AEs during the IHT of ICU patients with and without physician accompaniment. The preeducation mean nursing knowledge score was 30.8 ± 10.2 (scale 0-100), and postcurriculum test mean score was 80 ± 20.2 (p < .001). In a series of 200 ICU transports, the incidence of AEs was 21.5% (n = 43). In patients who were unstable prior to transport, there was no difference in complications with or without a physician present (p = 0.40, χ = 0.696, odds ratio = 0.643, 95% confidence interval: 0.245-1.96). Patient needs during transport were met with preexisting orders or treatment orders received telephonically. Nurses' knowledge of transport standards improved significantly with education. Physician presence did not affect outcomes. The interventions needed to respond to complications did not require physician presence. In this cohort, there was no statistically significant benefit from physician attendance in transport.


Asunto(s)
Enfermedades Cardiovasculares/terapia , Cuidados Críticos/normas , Enfermedad Crítica/terapia , Transporte de Pacientes , Enfermería de Cuidados Críticos , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Phys Rev Lett ; 118(10): 105901, 2017 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-28339274

RESUMEN

Most substitutional solutes in solids diffuse via vacancies. However, widely used analytic models for diffusivity make uncontrolled approximations in the relations between atomic jump rates that reduce accuracy. Symmetry analysis of the hexagonal close packed crystal identifies more distinct vacancy transitions than prior models, and a Green function approach computes diffusivity exactly for solutes in magnesium. We find large differences for the solute drag of Al, Zn, and rare earth solutes, and improved diffusion activation energies-highlighting the need for exact analytic transport models.

14.
J Nanosci Nanotechnol ; 17(2): 1068-075, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29676551

RESUMEN

In this paper, experimental results on thermal conductivity of TiO2-Water, TiO2-Ethylene Glycol and TiO2-Engine Oil nanofluids in concentration range between 0.25 to 2 volume percent and temperature range of 10­70 °C is presented. Results show that thermal conductivity of nanofluids increases with increasing concentration and lower enhancement is observed with temperature as compared with concentration. Maximum enhancements are 9.3%, 15% and 8.9% for 2% volume of TiO2 nanoparticles at 70 °C for TiO2-Water, TiO2-Ethylene Glycol and TiO2-Engine Oil nanofluids respectively. 4-input and 1-output Artificial Neural Network (ANN) approach is used to predict thermal conductivity of nanofluids. Experimental results obtained were compared with some theoretical models and ANN approach. It is observed that ANN approach gives better predictions and is in good agreement with experimental results.

15.
J Oral Maxillofac Surg ; 75(8): 1591-1600, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28419843

RESUMEN

PURPOSE: We performed a retrospective review of in-office removal of complex mandibular third molars with a dynamic image navigation system (DINS). MATERIALS AND METHODS: A retrospective review was conducted of cases completed from 2010 to 2014 by a single oral and maxillofacial surgeon. The average age of the patients was 47 years (range, 27 to 72 years). Extraction complexity was classified with Juodzbalys and Daugela's classification system. The included study cases had complexity scores of 9 or greater. Each patient received custom intraoral splints to secure the tracking array and underwent cone beam computed tomography image acquisition. All surgical procedures were performed with a precalibrated tracking straight handpiece under dynamic navigation. RESULTS: All 25 cases were treated successfully with the use of the DINS. Twelve of these cases were associated with pathologic lesions. Three patients were noted to have inferior alveolar nerve paresthesia. One patient sustained a pathologic fracture at week 2. Postoperative infections were noted in 7 cases, 2 of which had a pre-existing infection. One patient reported temporary limitation of mouth opening. A coronectomy was performed in 1 case. CONCLUSIONS: We present results using a new technology, the DINS, for removal of complex mandibular third molars. Potential advantages are 1) improved visualization and localization of anatomic structures such as the inferior alveolar nerve, lingual cortical plate, and adjacent roots; 2) improved control during osteotomy; 3) decreased surgical access requirements and reduction in overall bone removal; 4) ability to perform complex procedures successfully in an in-office setting; 5) decreased surgical time resulting from improved visualization; and 6) potential use as a teaching tool. Possible limitations of the use of an in-office DINS include increased cost, increased time attributed to presurgical planning, initial learning curve, and optical array interference by the surgeon or assistants during surgery.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/instrumentación , Procedimientos Quirúrgicos Ambulatorios/métodos , Tercer Molar/cirugía , Cirugía Asistida por Computador/instrumentación , Cirugía Asistida por Computador/métodos , Extracción Dental/instrumentación , Extracción Dental/métodos , Adulto , Anciano , Tomografía Computarizada de Haz Cónico , Equipo Dental de Alta Velocidad , Diseño de Equipo , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Modelos Dentales , Tercer Molar/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Impresión Tridimensional
16.
J Food Sci Technol ; 54(2): 279-292, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28242927

RESUMEN

The present study was undertaken to evaluate antimicrobial and antioxidant effect of essential oils on the quality of fresh (raw, ready to cook) chicken sausages. Several preliminary trials were carried out to optimize the level of four essential oils viz., clove oil, holybasil oil, thyme oil and cassia oil and these essential oils were incorporated at 0.25, 0.125, 0.25 and 0.125%, respectively in fresh chicken sausages. Quality evaluation and detailed storage stability studies were carried out for fresh chicken sausages for 20 days at refrigeration temperature (4 ± 1 °C). Refrigerated storage studies revealed that TBARS of control was significantly higher than treatment products whereas, total phenolics and DPPH activity was significantly lower in control. Among treatments, clove oil products had significantly lower TBARS but higher total phenolic content and DPPH activity followed by cassia oil, thyme oil and holybasil oil products. Microbial count of essential oil incorporated products were significantly lower than control and remained well below the permissible limit of fresh meat products (log107 cfu/g). Cassia oil products were observed with better anti-microbial characteristics than clove oil products at 0.25% level of incorporation, whereas, thyme oil products were better than holy basil oil products at 0.125% level. Storage studies revealed that clove oil (0.25%), holy basil oil (0.125%), cassia oil (0.25%) and thyme oil (0.125%) incorporated aerobically packaged and refrigerated fresh chicken sausages had approx. 4-5, 2-3, 5-6 and 2-3 days longer shelf life than control, respectively.

19.
J Calif Dent Assoc ; 42(5): 327-30, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25087351

RESUMEN

Preservation of space after premature loss of the second primary molar is essential to prevent mesial drifting of the permanent first molar. Various modifications of distal shoe space maintainers, which have been documented, are all nonfunctional in nature. This paper describes an innovative design of a functional distal shoe space maintainer that is intended to overcome the disadvantages of conventional non-functional space maintainers and that does not hamper the periodontal status of the abutment tooth.


Asunto(s)
Diente Molar/patología , Diseño de Aparato Ortodóncico , Mantenimiento del Espacio en Ortodoncia/instrumentación , Pérdida de Diente/terapia , Diente Primario/patología , Preescolar , Caries Dental/terapia , Estudios de Seguimiento , Humanos , Masculino , Soportes Ortodóncicos , Alambres para Ortodoncia , Pulpitis/terapia , Mantenimiento del Espacio en Ortodoncia/métodos , Extracción Dental , Movilidad Dentaria/terapia
20.
Neural Netw ; 170: 506-520, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38043371

RESUMEN

The objective of this study is to investigate the synchronization criteria under the sampled-data control method for multi-agent systems (MASs) with state quantization and time-varying delay. Currently, a looped Lyapunov-Krasovskii Functional (LKF) has been developed, which integrates information from the sampling interval to ensure that the leader system synchronizes with the follower system, resulting in a specific condition in the form of Linear Matrix Inequalities (LMIs). The LMIs can be easily solved using the LMI Control toolbox in Matlab. Finally, the proposed approach's feasibility and effectiveness are demonstrated through numerical simulations and comparative results.


Asunto(s)
Redes Neurales de la Computación , Factores de Tiempo
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