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1.
Healthcare (Basel) ; 12(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38727437

ABSTRACT

Rhodotorula mucilaginosa fungemia is rare and highly resistant to antifungal therapy. We herein report a case involving a 31-year-old male admitted after a high-velocity road traffic accident. He sustained a grade IV liver injury with right hepatic vein thrombosis, which necessitated an urgent laparotomy. Post-operatively, repeated imaging of the abdomen revealed the presence of a biloma. Percutaneous subdiaphragmatic drainage was carried out but appeared ineffective, prompting a second surgery for an urgent hemi-hepatectomy. The patient was then nursed in the intensive care unit (ICU); however, during his stay in the ICU, he became more sepsis, which was evident by worsening ventilatory support and a rise in septic parameters from the biochemistry parameters. Despite intravenous piperacillin-tazobactam and fluconazole, his septic parameters did not improve and a full septic workup was conducted and was found to be positive for Rhodotorula mucilaginosa from the blood cultures. After discussion with the infectious disease physicians and clinical microbiologists, it was decided to initiate a course of intravenous meropenem and amphotericin B based on minimum inhibitory concentration (MIC) values, considering the patient's extended ICU stay and catheter use. Eventually, after successfully weaning off mechanical ventilation, the patient was discharged from ICU care. This case underscores the necessity of individualized approaches, combining timely imaging, appropriate drainage techniques, and tailored treatments to optimize outcomes for such intricate post-traumatic complications.

2.
PLoS One ; 19(5): e0296909, 2024.
Article in English | MEDLINE | ID: mdl-38753667

ABSTRACT

The time fractional Schrödinger equation contributes to our understanding of complex quantum systems, anomalous diffusion processes, and the application of fractional calculus in physics and cubic B-spline is a versatile tool in numerical analysis and computer graphics. This paper introduces a numerical method for solving the time fractional Schrödinger equation using B-spline functions and the Atangana-Baleanu fractional derivative. The proposed method employs a finite difference scheme to discretize the fractional derivative in time, while a θ-weighted scheme is used to discretize the space directions. The efficiency of the method is demonstrated through numerical results, and error norms are examined at various values of the non-integer parameter, temporal directions, and spatial directions.


Subject(s)
Algorithms , Models, Theoretical , Quantum Theory , Computer Simulation
3.
Sci Rep ; 14(1): 6410, 2024 03 17.
Article in English | MEDLINE | ID: mdl-38494490

ABSTRACT

The present research investigates the double-chain deoxyribonucleic acid model, which is important for the transfer and retention of genetic material in biological domains. This model is composed of two lengthy uniformly elastic filaments, that stand in for a pair of polynucleotide chains of the deoxyribonucleic acid molecule joined by hydrogen bonds among the bottom combination, demonstrating the hydrogen bonds formed within the chain's base pairs. The modified extended Fan sub equation method effectively used to explain the exact travelling wave solutions for the double-chain deoxyribonucleic acid model. Compared to the earlier, now in use methods, the previously described modified extended Fan sub equation method provide more innovative, comprehensive solutions and are relatively straightforward to implement. This method transforms a non-linear partial differential equation into an ODE by using a travelling wave transformation. Additionally, the study yields both single and mixed non-degenerate Jacobi elliptic function type solutions. The complexiton, kink wave, dark or anti-bell, V, anti-Z and singular wave shapes soliton solutions are a few of the creative solutions that have been constructed utilizing modified extended Fan sub equation method that can offer details on the transversal and longitudinal moves inside the DNA helix by freely chosen parameters. Solitons propagate at a consistent rate and retain their original shape. They are widely used in nonlinear models and can be found everywhere in nature. To help in understanding the physical significance of the double-chain deoxyribonucleic acid model, several solutions are shown with graphics in the form of contour, 2D and 3D graphs using computer software Mathematica 13.2. All of the requisite constraint factors that are required for the completed solutions to exist appear to be met. Therefore, our method of strengthening symbolic computations offers a powerful and effective mathematical tool for resolving various moderate nonlinear wave problems. The findings demonstrate the system's potentially very rich precise wave forms with biological significance. The fundamentals of double-chain deoxyribonucleic acid model diffusion and processing are demonstrated by this work, which marks a substantial development in our knowledge of double-chain deoxyribonucleic acid model movements.


Subject(s)
Biological Science Disciplines , Nonlinear Dynamics , Base Pairing , Hydrogen Bonding , DNA/chemistry
4.
PLoS One ; 18(12): e0295525, 2023.
Article in English | MEDLINE | ID: mdl-38100449

ABSTRACT

Splines are piecewise polynomials that are as smooth as they can be without forming a single polynomial. They are linked at specific points known as knots. Splines are useful for a variety of problems in numerical analysis and applied mathematics because they are simple to store and manipulate on a computer. These include, for example, numerical quadrature, function approximation, data fitting, etc. In this study, cubic B-spline (CBS) functions are used to numerically solve the time fractional diffusion wave equation (TFDWE) with Caputo-Fabrizio derivative. To discretize the spatial and temporal derivatives, CBS with θ-weighted scheme and the finite difference approach are utilized, respectively. Convergence analysis and stability of the presented method are analyzed. Some examples are used to validate the suggested scheme, and they show that it is feasible and fairly accurate.


Subject(s)
Algorithms , Diffusion
5.
Heliyon ; 9(10): e20852, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37916109

ABSTRACT

The analytical soliton solutions place a lot of value on birefringent fibres. The major goal of this study is to generate novel forms of soliton solutions for the Radhakrishnan-Kundu-Lakshmanan equation, which depicts unstable optical solitons that arise from optical propagations using birefringent fibres. The (presumably new) extended direct algebraic (EDA) technique is used here to extract a large number of solutions for RKLE. It gives soliton solutions up to thirty-seven, which essentially correspond to all soliton families. This method's ability to determine many sorts of solutions through a single process is one of its key advantages. Additionally, it is simple to infer that the technique employed in this study is really straightforward yet one of the quite effective approaches to solving nonlinear partial differential equations so, this novel extended direct algebraic (EDA) technique may be regarded as a comprehensive procedure. The resulting solutions are found to be hyperbolic, periodic, trigonometric, bright and dark, combined bright-dark, and W-shaped soliton, and these solutions are visually represented by means of 2D, 3D, and density plots. The present study can be extended to investigate several other nonlinear systems to understand the physical insights of the optical propagations through birefringent fibre.

6.
Heliyon ; 9(9): e19307, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37810099

ABSTRACT

Spline curves are very prominent in the mathematics due to their simple construction, accuracy of assessment and ability to approximate complicated structures into interactive curved designs. A spline is a smooth piece-wise polynomial function. The primary goal of this study is to use extended cubic B-spline (ExCuBS) functions with a new second order derivative approximation to obtain the numerical solution of the weakly singular kernel (SK) non-linear fractional partial integro-differential equation (FPIDE). The spatial and temporal fractional derivatives are discretized by ExCuBS and the Caputo finite difference scheme, respectively. The present study found that it is stable and convergent. The validity of the current approach is examined on a few test problems, and the obtained outcomes are compared with those that have previously been reported in the literature.

7.
Medicine (Baltimore) ; 102(19): e33721, 2023 May 12.
Article in English | MEDLINE | ID: mdl-37171298

ABSTRACT

BACKGROUND: Shivering is described as an involuntary, repetitive activity of the skeletal muscles that can have deleterious effects on anaesthetized patients. This study aimed to evaluate the effectiveness of phenylephrine infusion in preventing perioperative shivering in patients undergoing lower segment cesarean section under spinal anesthesia and to observe the change in the patient's core temperature between the study and control groups. METHODS: A total of 118 patients scheduled for elective lower segment cesarean section under spinal anesthesia were recruited for this prospective, double-blind, randomized controlled study. The patients were randomized into 2 groups with 59 patients per group. The phenylephrine Group received phenylephrine infusion at a rate of 0.5 mcg/kg/minutes, while the Control Group received normal saline at an equivalent rate. Systolic and diastolic blood pressure, heart rate, core temperature, and the presence and intensity of shivering were recorded before induction and every 15 minutes intraoperatively and postoperatively. RESULTS: The incidence of intraoperative shivering was significantly lower in the Phenylephrine Group compared to control group (29.1% vs 47.5% respectively; P = .044). Postoperatively, the Phenylephrine Group also had a lower incidence of shivering (34.5% vs 42.4%), but the difference was not statistically significant (P value = 0.391). There were no significant differences in the intensity of shivering between the 2 groups perioperatively, as well as in the systolic and diastolic blood pressure and core temperature. The phenylephrine Group showed a significantly lower heart rate at 15, 30, and 45 minutes after spinal block (P value = .005, .000, and .008, respectively), and at 0 and 30 minutes (P value = .004 and .020 respectively) in the recovery room. There were no significant differences in perioperative adverse events such as hypotension, hypertension, and bradycardia. CONCLUSION: Phenylephrine infusion reduces the incidence of perioperative shivering in lower segment cesarean sections under spinal anesthesia.


Subject(s)
Anesthesia, Obstetrical , Anesthesia, Spinal , Hypotension , Humans , Pregnancy , Female , Phenylephrine/therapeutic use , Vasoconstrictor Agents/therapeutic use , Cesarean Section/adverse effects , Prospective Studies , Shivering , Hypotension/etiology , Anesthesia, Spinal/adverse effects , Double-Blind Method , Anesthesia, Obstetrical/adverse effects
8.
Heliyon ; 9(5): e15717, 2023 May.
Article in English | MEDLINE | ID: mdl-37206045

ABSTRACT

In this study, the compatible extensions of the (G'/G)-expansion approach and the generalized (G'/G)-expansion scheme are proposed to generate scores of radical closed-form solutions of nonlinear fractional evolution equations. The originality and improvements of the extensions are confirmed by their application to the fractional space-time paired Burgers equations. The application of the proposed extensions highlights their effectiveness by providing dissimilar solutions for assorted physical forms in nonlinear science. In order to explain some of the wave solutions geometrically, we represent them as two- and three-dimensional graphs. The results demonstrate that the techniques presented in this study are effective and straightforward ways to address a variety of equations in mathematical physics with conformable derivative.

9.
Chaos Solitons Fractals ; : 113722, 2023 Jun 26.
Article in English | MEDLINE | ID: mdl-38620099

ABSTRACT

The global impact of COVID-19 has led to the development of numerous mathematical models to understand and control the pandemic. However, these models have not fully captured how the disease's dynamics are influenced by both within-host and between-host factors. To address this, a new mathematical model is proposed that links these dynamics and incorporates immune response. The model is compartmentalized with a fractional derivative in the sense of Caputo-Fabrizio, and its properties are studied to show a unique solution. Parameter estimation is carried out by fitting real-life data, and sensitivity analysis is conducted using various methods. The model is then numerically implemented to demonstrate how the dynamics within infected hosts drive human-to-human transmission, and various intervention strategies are compared based on the percentage of averted deaths. The simulations suggest that a combination of medication to boost the immune system, prevent infected cells from producing the virus, and adherence to COVID-19 protocols is necessary to control the spread of the virus since no single intervention strategy is sufficient.

10.
Front Med (Lausanne) ; 9: 1058121, 2022.
Article in English | MEDLINE | ID: mdl-36569164

ABSTRACT

Pseudomonas putida is a rare pathogen leading to nosocomial and central nervous system infections. Despite having a low virulence and being a rare organism to cause bacteremia, it can evolve into a multidrug-resistant organism and lead to mortality and morbidity in the intensive care setting. A 64-year-old male gardener was presented with extensive acute subarachnoid hemorrhage with intraventricular extension causing hydrocephalus requiring embolization and coiling following a cerebral angiogram, which showed bilateral posterior circulation aneurysm and left anterior circulation aneurysm. External ventricular drain (EVD) was inserted given the worsening hydrocephalus. During his stay in the intensive care unit (ICU), he was becoming more septic and a full septic workup including a cerebral spinal fluid culture taken from the indwelling catheter of the EVD and was found to be positive for a ceftazidime-sensitive strain of P. putida. Following the treatment with intravenous ceftazidime for 1 week and a revision of the EVD on day 32 of admission, he continued to recover well and showed an improvement in his Glasgow Coma Scale (GCS) and septic parameters. Eventually, he was able to wean off mechanical ventilation. He was discharged from ICU care to the neurosurgical ward with supplemental oxygen on day 42 of admission. It is necessary to be aware of the possibility of nosocomial P. putida infection, especially in patients with indwelling catheters, and to consider the early initiation of appropriate antibiotic regimens once detected as well as strict precautions in hygiene during the management of these patients to avoid further development of multi-drug resistant (MDR) strains.

11.
Cureus ; 14(9): e29425, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36299949

ABSTRACT

Background Postpartum depression has been linked to undesirable outcomes for mother-infant dyads, interfering with childcare and breastfeeding practices. This study aimed to determine the prevalence of depressive symptoms among mothers during the postpartum period and its association with breastfeeding and postpartum experiences. Methodology This cross-sectional study involved mothers of hospitalized infants (n = 219) at two tertiary hospitals in Klang Valley, Malaysia. Mothers were screened for postpartum depression using the Edinburgh Postnatal Depression Scale with a cut-off of ≥12 for positive screening for depression. Mothers were asked to complete questionnaires on breastfeeding experience, which included breastfeeding self-efficacy and challenges. The questionnaires also collected information on postnatal experiences, including birth outcomes, anxiety and stress levels, and social support. Multiple linear regression was used to ascertain the association of postpartum depression levels with breastfeeding and postnatal experiences. Results Overall, 30% of mothers in this study screened positive for depression. Based on multiple linear regression, a higher score of postpartum depression was significantly associated with unpleasant breastfeeding and postnatal experiences reflected by increased scores of anxiety and stress, lower infant birth weight, increased breastfeeding problems, and lower level of social support (p < 0.005). Conclusions Maternal emotions, birth outcomes, breastfeeding issues, and social support were associated with postpartum depression. Efforts should be made to increase maternal support, and screening for maternal depression during infant hospital stays should be encouraged.

12.
BMJ Paediatr Open ; 5(1): e001149, 2021.
Article in English | MEDLINE | ID: mdl-34595358

ABSTRACT

Objectives: To determine a 10-year trend of survival, morbidities and care practices, and predictors of in-hospital mortality in very preterm neonates (VPTN, gestation 22 to <32 weeks) in the Malaysian National Neonatal Registry. Design: Retrospective cohort study. Setting: 43 Malaysian neonatal intensive care units. Patients: 29 010 VPTN (without major malformations) admitted between 1 January 2009 and 31 December 2018. Main outcome measures: Care practices, survival, admission hypothermia (AH, <36.5°C), late-onset sepsis (LOS), pneumothorax, necrotising enterocolitis grade 2 or 3 (NEC), severe intraventricular haemorrhage (sIVH, grade 3 or 4) and bronchopulmonary dysplasia (BPD). Results: During this 10-year period, there was increased use of antenatal steroid (ANS), lower segment caesarean section (LSCS) and early continuous positive airway pressure (eCPAP); but decreased use of surfactant therapy. Survival had increased from 72% to -83.9%. The following morbidities had decreased: LOS (from 27.9% to 7.1%), pneumothorax (from 6.0% to 2.7%), NEC (from 8.1% to 4.7%) and sIVH (from 12.2% to 7.5%). However, moderately severe AH (32.0°C-35.9°C) and BPD had increased. Multiple logistic regression analyses showed that lower birth weight, no ANS, no LSCS, admission to neonatal intensive care unit with <100 VPTN admissions/year, no surfactant therapy, no eCPAP, moderate and severe AH, LOS, pneumothorax, NEC and sIVH were significant predictors of mortality. Conclusion: Survival and major morbidities had improved modestly. Failure to use ANS, LSCS, eCPAP and surfactant therapy, and failure to prevent AH and LOS increased risk of mortality.


Subject(s)
Infant, Extremely Premature , Infant, Premature, Diseases , Cesarean Section , Female , Humans , Infant, Newborn , Infant, Premature, Diseases/epidemiology , Morbidity , Pregnancy , Registries , Retrospective Studies
13.
Int J Appl Comput Math ; 7(3): 67, 2021.
Article in English | MEDLINE | ID: mdl-33898652

ABSTRACT

To understand the dynamics of COVID-19 in Nigeria, a mathematical model which incorporates the key compartments and parameters regarding COVID-19 in Nigeria is formulated. The basic reproduction number is obtained which is then used to analyze the stability of the disease-free equilibrium solution of the model. The model is calibrated using data obtained from Nigeria Centre for Disease Control and key parameters of the model are estimated. Sensitivity analysis is carried out to investigate the influence of the parameters in curtailing the disease. Using Pontryagin's maximum principle, time-dependent intervention strategies are optimized in order to suppress the transmission of the virus. Numerical simulations are then used to explore various optimal control solutions involving single and multiple controls. Our results suggest that strict intervention effort is required for quick suppression of the disease.

14.
Plants (Basel) ; 10(4)2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33917172

ABSTRACT

Labisia pumila is a precious herb in Southeast Asia that is traditionally used as a health supplement and has been extensively commercialized due to its claimed therapeutic properties in boosting a healthy female reproductive system. Indigenous people used these plants by boiling the leaves; however, in recent years it has been marketed as powdered or capsuled products. Accordingly, accuracy in determination of the authenticity of these modern herbal products has faced great challenges. Lack of authenticity is a public health risk because incorrectly used herbal species can cause adverse effects. Hence, any measures that may aid product authentication would be beneficial. Given the widespread use of Labisia herbal products, the current study focuses on authenticity testing via an integral approach of DNA barcoding and qualitative analysis using HPLC. This study successfully generated DNA reference barcodes (ITS2 and rbcL) for L. pumila var. alata and pumila. The DNA barcode that was generated was then used to identify species of Labisia pumila in herbal medicinal products, while HPLC was utilized to determine their quality. The findings through the synergistic approach (DNA barcode and HPLC) implemented in this study indicate the importance of both methods in providing the strong evidence required for the identification of true species and to examine the authenticity of such herbal medicinal products.

15.
Chaos Solitons Fractals ; 152: 111427, 2021 Nov.
Article in English | MEDLINE | ID: mdl-36569784

ABSTRACT

In this work, a mathematical model consisting of a compartmentalized coupled nonlinear system of fractional order differential equations describing the transmission dynamics of COVID-19 is studied. The fractional derivative is taken in the Atangana-Baleanu-Caputo sense. The basic dynamic properties of the fractional model such as invariant region, existence of equilibrium points as well as basic reproduction number are briefly discussed. Qualitative results on the existence and uniqueness of solutions via a fixed point argument as well as stability of the model solutions in the sense of Ulam-Hyers are furnished. Furthermore, the model is fitted to the COVID-19 data circulated by Nigeria Centre for Disease Control and the two-step Adams-Bashforth method incorporating the noninteger order parameter is used to obtain an iterative scheme from which numerical results for the model can be generated. Numerical simulations for the proposed model using Adams-Bashforth iterative scheme are presented to describe the behaviors at distinct values of the fractional index parameter for of each of the system state variables. It was shown numerically that the value of fractional index parameter has a significant effect on the transmission behavior of the disease however, the infected population (the exposed, the asymptomatic infectious, the symptomatic infectious) shrinks with time when the basic reproduction number is less than one irrespective of the value of fractional index parameter.

16.
BMC Cancer ; 20(1): 721, 2020 Aug 03.
Article in English | MEDLINE | ID: mdl-32746799

ABSTRACT

BACKGROUND: Hematopoietic cell transplantation (HCT) is a curative option for a growing number of patients with hematologic diseases and malignancies. However, HCT-related factors, such as total body irradiation used for conditioning, graft-versus-host disease, and prolonged exposure to immunosuppressive therapy, result in very high risk for melanoma and non-melanoma skin cancer (NMSC). In fact, skin cancer is the most common subsequent neoplasm in HCT survivors, tending to develop at a time when survivors' follow-up care has largely transitioned to the primary care setting. The goal of this study is to increase skin cancer screening rates among HCT survivors through patient-directed activation alone or in combination with physician-directed activation. The proposed intervention will identify facilitators of and barriers to risk-based screening in this population and help reduce the burden of cancer-related morbidity after HCT. METHODS/DESIGN: 720 HCT survivors will be enrolled in this 12-month randomized controlled trial. This study uses a comparative effectiveness design comparing (1) patient activation and education (PAE, N = 360) including text messaging and print materials to encourage and motivate skin examinations; (2) PAE plus primary care physician activation (PAE + Phys, N = 360) adding print materials for the physician on the HCT survivors' increased risk of skin cancer and importance of conducting a full-body skin exam. Patients on the PAE + Phys arm will be further randomized 1:1 to the teledermoscopy (PAE + Phys+TD) adding physician receipt of a portable dermatoscope to upload images of suspect lesions for review by the study dermatologist and an online course with descriptions of dermoscopic images for skin cancers. DISCUSSION: When completed, this study will provide much-needed information regarding strategies to improve skin cancer detection in other high-risk (e.g. radiation-exposed) cancer survivor populations, and to facilitate screening and management of other late effects (e.g. cardiovascular, endocrine) in HCT survivors. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04358276 . Registered 24 April 2020.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Physical Examination , Skin Neoplasms/diagnosis , Cancer Survivors , Costs and Cost Analysis , Hematopoietic Stem Cell Transplantation/methods , Hematopoietic Stem Cell Transplantation/statistics & numerical data , Humans , Patient Education as Topic , Physical Examination/methods , Physicians, Primary Care , Self-Examination/methods , Skin Neoplasms/etiology
17.
Genome ; 61(5): 371-378, 2018 May.
Article in English | MEDLINE | ID: mdl-29425468

ABSTRACT

rRNAs are non-coding RNAs present in all prokaryotes and eukaryotes. In eukaryotes there are four rRNAs: 18S, 5.8S, 28S, originating from a common precursor (45S), and 5S. We have recently discovered the existence of two distinct developmental types of rRNA: a maternal-type, present in eggs and a somatic-type, expressed in adult tissues. Lately, next-generation sequencing has allowed the discovery of new small-RNAs deriving from longer non-coding RNAs, including small-RNAs from rRNAs (srRNAs). Here, we systemically investigated srRNAs of maternal- or somatic-type 18S, 5.8S, 28S, with small-RNAseq from many zebrafish developmental stages. We identified new srRNAs for each rRNA. For 5.8S, we found srRNA consisting of the 5' or 3' halves, with only the latter having different sequence for the maternal- and somatic-types. For 18S, we discovered 21 nt srRNA from the 5' end of the 18S rRNA with a striking resemblance to microRNAs; as it is likely processed from a stem-loop precursor and present in human and mouse Argonaute-complexed small-RNA. For 28S, an abundant 80 nt srRNA from the 3' end of the 28S rRNA was found. The expression levels during embryogenesis of these srRNA indicate they are not generated from rRNA degradation and might have a role in the zebrafish development.


Subject(s)
Argonaute Proteins/genetics , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 5.8S/genetics , RNA, Small Untranslated/genetics , Zebrafish/genetics , Animals , Argonaute Proteins/metabolism , Base Sequence , Embryo, Nonmammalian/metabolism , Embryonic Development/genetics , Gene Expression Regulation, Developmental , High-Throughput Nucleotide Sequencing , Nucleic Acid Conformation , Protein Binding , RNA, Ribosomal, 18S/metabolism , RNA, Ribosomal, 28S/metabolism , RNA, Ribosomal, 5.8S/metabolism , RNA, Small Untranslated/metabolism , Zebrafish/growth & development , Zebrafish/metabolism , Zygote/growth & development , Zygote/metabolism
18.
AIP Conf Proc ; 1660(1): 050007, 2015 May 15.
Article in English | MEDLINE | ID: mdl-32255874

ABSTRACT

Human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) is pandemic. It has affected nearly 60 million people since the detection of the disease in 1981 to date. In this paper basic deterministic HIV/AIDS model with mass action incidence function are developed. Stability analysis is carried out. And the disease free equilibrium of the basic model was found to be locally asymptotically stable whenever the threshold parameter (RO) value is less than one, and unstable otherwise. The model is extended by introducing two optimal control strategies namely, CD4 counts and treatment for the infective using optimal control theory. Numerical simulation was carried out in order to illustrate the analytic results.

19.
PLoS One ; 8(5): e64618, 2013.
Article in English | MEDLINE | ID: mdl-23741355

ABSTRACT

The generalized and improved (G'/G)-expansion method is a powerful and advantageous mathematical tool for establishing abundant new traveling wave solutions of nonlinear partial differential equations. In this article, we investigate the higher dimensional nonlinear evolution equation, namely, the (3+1)-dimensional modified KdV-Zakharov-Kuznetsev equation via this powerful method. The solutions are found in hyperbolic, trigonometric and rational function form involving more parameters and some of our constructed solutions are identical with results obtained by other authors if certain parameters take special values and some are new. The numerical results described in the figures were obtained with the aid of commercial software Maple.


Subject(s)
Algorithms , Nonlinear Dynamics , Software , Computer Graphics , Computer Simulation
20.
Paediatr Anaesth ; 23(1): 58-67, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23167288

ABSTRACT

AIM: To determine if the addition of adrenaline, clonidine, or their combination altered the pharmacokinetic profile of levobupivacaine administered via the caudal epidural route in children. METHODS: Children aged <18 years old scheduled to undergo sub-umbilical surgery were administered caudal levobupivacaine plain 2.5 mg · ml(-1) or with adjuvants adrenaline 5 mcg · ml(-1) or clonidine 2 mcg · ml(-1) or their combination. Covariate analysis included weight and postnatal age (PNA). Time-concentration profile analysis was undertaken using nonlinear mixed effects models. A one-compartment linear disposition model with first-order input and first-order elimination was used to describe the data. The effect of either clonidine or adrenaline on absorption was investigated using a scaling parameter (Fabs(CLON), Fabs(ADR)) applied to the absorption half-life (Tabs). RESULTS: There were 240 children (median weight 11.0, range 1.9-56.1 kg; median postnatal age 16.7, range 0.6-167.6 months). Absorption of levobupivacaine was faster when mixed with clonidine (Fabs(CLON) 0.60; 95%CI 0.44, 0.83) but slower when mixed with adrenaline (Fabs(ADR) 2.12; 95%CI 1.45, 3.08). The addition of adrenaline to levobupivacaine resulted in a bifid absorption pattern. While initial absorption was unchanged (Tabs 0.15 h 95%CI 0.12, 0.18 h), there was a late absorption peak characterized by a Tabs(LATE) 2.34 h (95%CI 1.44, 4.97 h). The additional use of clonidine with adrenaline had minimal effect on the bifid absorption profile observed with adrenaline alone. Neither clonidine nor adrenaline had any effect on clearance. The population parameter estimate for volume of distribution was 157 l 70 kg(-1). Clearance was 6.5 l · h(-1) 70 kg(-1) at 1-month PNA and increased with a maturation half-time of 1.6 months to reach 90% of the mature value (18.5 l · h(-1) 70 kg(-1)) by 5 months PNA. CONCLUSIONS: The addition of adrenaline decreases the rate of levobupivacaine systemic absorption, reducing peak concentration by half. Levobupivacaine concentrations with adrenaline adjuvant were reduced compared to plain levobupivacaine for up to 3.5 hours. Clonidine as an adjuvant results in faster systemic absorption of levobupivacaine and similar concentration time profile to levobupivacaine alone. Adding adrenaline with clonidine does not alter the concentration profile observed with adrenaline alone.


Subject(s)
Adrenergic alpha-Agonists/pharmacokinetics , Anesthesia, Epidural/methods , Anesthetics, Local/pharmacokinetics , Clonidine/pharmacokinetics , Epinephrine/pharmacokinetics , Adolescent , Adrenergic alpha-2 Receptor Agonists/pharmacokinetics , Age Factors , Anesthetics, Combined/pharmacokinetics , Bupivacaine/analogs & derivatives , Bupivacaine/pharmacokinetics , Child , Drug Interactions , Female , Half-Life , Humans , Levobupivacaine , Male
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