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2.
J Mater Chem B ; 12(16): 3996-4003, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38563677

RESUMO

Encapsulation of enzymes within porous materials has shown great promise for protecting enzymes from denaturation, increasing their tolerance to harsh environments and promoting their industrialization. However, controlling the conformational freedom of the encapsulated enzymes to enhance their catalytic performance remains a great challenge. To address this issue, herein, following immobilization of GOx and HRP on a thermo-responsive porous poly(styrene-maleic-anhydride-N-isopropylacrylamide) (PSMN) membrane, a GOx-HRP@PSMN@HZIF-8 composite was fabricated by encapsulating GOx-HRP@PSMN in hollow ZIF-8 (HZIF-8) with liposome (L) as the sacrificial template. The improved conformational freedom for enzymes arising from the hollow cavity formed in ZIF-8 through the removal of L enhanced the mass transfer and dramatically promoted the catalytic activity of the composite. Interestingly, at high temperature, the coiled PN moiety in PSMN provided the confinement effect for GOx-HRP, which also significantly boosted the catalytic performance of the composites. Compared to the maximum catalytic reaction rates (Vmax) of GOx-HRP@PSMN@LZIF-8, the free enzyme and GOx-HRP@ZIF-8, the Vmax of the GOx-HRP@PSMN@HZIF-8 composite exhibited an impressive 17.8-fold, 10.8-fold and 6.0-fold enhancement at 37 °C, respectively. The proposed composites successfully demonstrated their potential as catalytic platforms for the colorimetric detection of glucose in a cascade reaction. This study paves a new way for overcoming the current limitations of immobilizing enzymes in porous materials and the use of smart polymers for the potential fabrication of enzyme@polymer@MOF composites with tunable conformational freedom and confinement effect.


Assuntos
Enzimas Imobilizadas , Glucose Oxidase , Estruturas Metalorgânicas , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Polímeros/química , Propriedades de Superfície , Porosidade , Tamanho da Partícula , Catálise , Biocatálise , Poliestirenos/química
3.
ACS Nano ; 18(18): 11978-11987, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652759

RESUMO

The interplay between strong Coulomb interactions and kinetic energy leads to intricate many-body competing ground states owing to quantum fluctuations in 2D electron and hole gases. However, the simultaneous observation of quantum critical phenomena in both electron and hole regimes remains elusive. Here, we utilize anisotropic black phosphorus (BP) to show density-driven metal-insulator transition with a critical conductance ∼e2/h which highlights the significant role of quantum fluctuations in both hole and electron regimes. We observe a T-linear resistivity from the deep metallic phase to the metal-insulator boundary at moderate temperatures, while it turns to Fermi liquid behavior in the deep metallic phase at low temperatures in both regimes. An analysis of the resistivity suggests that disorder-dominated transport leads to T-linear behavior in the hole regime, while in the electron regime, the T-linear resistivity results from strong Coulomb interactions, suggestive of strange-metal behavior. Successful scaling collapse of the resistivity in the T-linear region demonstrates the link between quantum criticality and the T-linear resistivity in both regimes. Our study provides compelling evidence that ambipolar BP could serve as an exciting testbed for investigating exotic states and quantum critical phenomena in hole and electron regimes of 2D semiconductors.

4.
J Pharm Bioallied Sci ; 16(Suppl 1): S753-S756, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595546

RESUMO

Objective: The present study aimed to conduct an assessment of parents' knowledge, attitudes, and practices toward methamphetamine "shabu" abuse among youth and its risk factors. Materials and Methods: The present cross-sectional descriptive study was conducted on a sample of 1179 parents. Parents were assured that questionnaire content would stay classified and was given anonymously. It had 20 demographic, drug use, and addiction treatment questions. Statistical Package for Social Sciences v. 24 and Chi-Square test were used to examine the data after evaluating and coding it. Results: Out of a total of 1179 participants, only 11% had not heard about shabu, about 38% did not know the main symptoms of crystal addiction, and 46% did not know the long side effects of crystal addiction. The majority of participants mentioned that shabu is available in powder format (57%) or liquid (13%), while 27% did not know its form. Most of the participants (97%) think that the drug of shabu or crystal or ice is dangerous; about 60% of participants mentioned that there is an addict in the family. Conclusion: Parents have good knowledge levels regarding different aspects of methamphetamine or shabu abuse, symptoms, and its risk factors. Further in-depth studies are needed at whole Saudi Arabia.

5.
Heliyon ; 10(3): e25471, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322963

RESUMO

In traditional statistics, all research endeavors revolve around utilizing precise, crisp data for the predictive estimation of population mean in survey sampling, when the supplementary information is accessible. However, these types of estimates often suffer from bias. The major aim is to uncover the most accurate estimates for the unknown value of the population mean while minimizing the mean square error (MSE). We have employed the neutrosophic approach, which is the extension of classical statistics that deals with the uncertain, vague, and indeterminate information, and proposed a neutrosophic predictive estimator of finite population mean using the kernel regression. The proposed estimator does not yield a single numerical value but instead provides an interval range within which the population parameter is likely to exist. This approach enhances the efficiency of the estimators by offering an estimated interval that encompasses the unknown value of the population mean with the least possible mean squared error (MSE). The simulation-based efficiency of the proposed estimator is discussed using the Sine, Bump and real-time temperature data set of Islamabad by using symmetric (Gaussian) kernel. The proposed non-parametric neutrosophic estimator has shown more effective results under the various bandwidth selectors than the adapted neutrosophic estimators.

6.
Small ; : e2310946, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38229536

RESUMO

Owing to their extraordinary photophysical properties, organometal halide perovskites are emerging as a new material class for X-ray detection. However, the existence of toxic lead makes their commercialization questionable and should readily be replaced. Accordingly, several lead alternatives have been introduced into the framework of conventional perovskites, resulting in various new perovskite dimensionalities. Among these, Pb-free lower dimensional perovskites (LPVKs) not only show promising X-ray detecting properties due to their higher ionic migration energy, wider and tunable energy bandgap, smaller dark currents, and structural versatility but also exhibit extended environmental stability. Herein, first, the structural organization of the PVKs (including LPVKs) is summarized. In the context of X-ray detectors (XDs), the outstanding properties of the LPVKs and active layer synthesis routes are elaborated afterward. Subsequently, their applications in direct XDs are extensively discussed and the device performance, in terms of the synthesis method, device architecture, active layer size, figure of merits, and device stability are tabulated. Finally, the review is concluded with an in-depth outlook, thoroughly exploring the present challenges to LPVKs XDs, proposing innovative solutions, and future directions. This review provides valuable insights into optimizing non-toxic Pb-free perovskite XDs, paving the way for future advancements in the field.

7.
Pak J Med Sci ; 40(1Part-I): 20-25, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38196467

RESUMO

Objective: The current study was designed to explore the relationship of TIMI and SYNTAX risk score to predict the CAD extent and severity in STEMI patients. Methods: For this cross-sectional study, 304 STEMI patients undergoing PPCI were enrolled at Department of Interventional Cardiology NICVD Karachi from September 2021 to January 2022. and the TIMI risk score was determined at enrolment. Based on these scorings, the patients were grouped as low, intermediate, and high risk, i.e., a score of ≤ 3, 4 to 7, and ≥ 8, respectively. The SYNTAX scores were utilized to assess the extent of CAD. Results: Statistically significant difference was found in symptoms to balloon time (p=0.001), history of diabetes (p=0.006), angina (p=0.011), obesity (p=0.048), STEMI type (p=0.003), Killip classes (p=0.000), Infarct-Related Artery (p=0.006), number of diseased vessels (p<0.01), LMS > 50% (p=0.000), PCI type (p<0.01), collateral circulation (p<0.01), In-hospital mortality (p<0.01), LV support (p<0.01), and post-procedural TIMI flow (p=0.013), among the three TIMI risk groups. Significant correlation was found among TIMI risk score and SYNTAX score. Conclusion: It is observed that the TIMI risk scores are highly correlated with the SYNTAX Score in predicting the CAD severity in STEMI patients.

8.
Chem Rec ; 24(1): e202300247, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37933973

RESUMO

The high-temperature solid oxide fuel cells (SOFCs) are the most efficient and green conversion technology for electricity generation from hydrogen-based fuel as compared to conventional thermal power plants. Many efforts have been made to reduce the high operating temperature (>800 °C) to intermediate/low operating temperature (400 °C

9.
J Chromatogr A ; 1714: 464595, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38141483

RESUMO

Fabricating polymeric coatings that are responsive to multiple/dual stimuli is crucial and remains a major challenge in the development of highly efficient open tubular capillary electrochromatography (OT-CEC). In this study, a pH and temperature-responsive block copolymer, poly(styrene-maleic anhydride 2-dimethylamino ethyl methacrylate), P(St-MAn-DMAEMA), was designed and synthesized. Using P(St-MAn-DMAEMA) as the coating, an OT-CEC protocol was constructed for the analysis of chromones. The morphology and hydrophobicity-hydrophilicity of the polymeric coating could change via varying the environmental conditions, affecting the separation efficiency of OT-CEC. Interestingly, the best performance of OT-CEC was achieved at pH 9.7 and 45 °C via tuning the interactions between the coating and the analytes. Additionally, the proposed OT-CEC method exhibited a good linear range for the detection of the three test chromones from 10.0 to 100.0 µM, with all correlation coefficients (R2) >0.997. The coatings also had good stability and reusability. This work provides an approach for the preparation of new multiple-stimuli-responsive polymeric coatings for the establishment of OT-CEC systems.


Assuntos
Eletrocromatografia Capilar , Polímeros , Humanos , Polímeros/química , Eletrocromatografia Capilar/métodos , Metacrilatos
10.
Mol Biotechnol ; 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37839042

RESUMO

The economic exploration of renewable energy resources has hot fundamentals among the countries besides dwindling energy resources and increasing public pressure. Cellulose accumulation is a major bio-natural resource from agricultural waste. Cellulases are the most potential enzymes that systematically degrade cellulosic biomass into monomers which could be further processed into several efficient value-added products via chemical and biological reactions including useful biomaterial for human benefits. This could lower the environmental risks problems followed by an energy crisis. Cellulases are mainly synthesized by special fungal genotypes. The strain Trichoderma orientalis could highly express cellulases and was regarded as an ideal strain for further research, as the genetic tools have found compatibility for cellulose breakdown by producing effective cellulose-degrading enzymes. This strain has found a cellulase production of about 35 g/L that needs further studies for advancement. The enzyme activity of strain Trichoderma orientalis needed to be further improved from a molecular level which is one of the important methods. Considering synthetic biological approaches to unveil the genetic tools will boost the knowledge about commercial cellulases bioproduction. Several genetic transformation methods were significantly cited in this study. The transformation approaches that are currently researchers are exploring is transcription regulatory factors that are deeply explained in this study, that are considered essential regulators of gene expression.

11.
Micromachines (Basel) ; 14(9)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37763840

RESUMO

Multilayer piezocomposite transducers are widely used in many applications where broad bandwidth is required for tracking and detection purposes. However, it is difficult to operate these multilayer transducers efficiently under frequencies of 100 kHz. Therefore, this work presents the modeling and optimization of a five-layer piezocomposite transducer with ten variables of nonuniform layer thicknesses and different volume fractions by exploiting the strength of the genetic algorithm (GA) with a one-dimensional model (ODM). The ODM executes matrix manipulation by resolving wave equations and produces mechanical output in the form of pressure and electrical impedance. The product of gain and bandwidth is the required function to be maximized in this multi-objective and multivariate optimization problem, which is a challenging task having ten variables. Converting it into the minimization problem, the reciprocal of the gain-bandwidth product is considered. The total thickness is adjusted to keep the central frequency at approximately 50-60 kHz. Piezocomposite transducers with three active materials, PZT5h, PZT4d, PMN-PT, and CY1301 polymer, as passive materials were designed, simulated, and statistically evaluated. The results show significant improvement in gain bandwidth compared to previous existing techniques.

12.
BMJ Case Rep ; 16(6)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37399348

RESUMO

A patient in her early 20s presented with blood-stained sputum and shortness of breath. Initially, she was treated for pneumonia. Later, upon exacerbation of symptoms, further investigations were done which exhibited a left atrial mass causing compression of contralateral atrium. She underwent surgical resection of the mass, which was initially mistaken as myxoma. However, histopathological correlation revealed spindle cell sarcoma with focal myogenic differentiation. This case report highlights the role of Radiation Therapy in adjuvant setting with promising impact on improving local control after R2 resection. Cardiac spindle cell sarcoma, being one of the rarest cardiac tumours reported to date, warrants establishment of a Rare Tumour Multidisciplinary Team for management of such malignancies.


Assuntos
Neoplasias Cardíacas , Mixoma , Sarcoma , Feminino , Humanos , Sarcoma/radioterapia , Sarcoma/cirurgia , Sarcoma/diagnóstico , Átrios do Coração/patologia , Neoplasias Cardíacas/radioterapia , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico
13.
J Pak Med Assoc ; 73(6): 1297-1301, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37427635

RESUMO

Synovial Sarcoma (SS) is a rare soft-tissue malignant tumour. Its presentation in the head and neck region is uncommon. Because of the complex anatomy of the head and neck region, surgery with clear margins is not achievable. In such cases, a multi-modality approach is required as there is no established standard of care. In this report, we share the case of a girl who presented with nasal obstruction. Imaging revealed a mass involving the left nasal cavity, paranasal sinuses without intracranial extension. It was diagnosed as synovial sarcoma. She underwent surgical excision and adjuvant radiation therapy (RT) to the tumour bed, followed by an incomplete course of chemotherapy. Later on, she developed systemic disease. Considering the rarity of this case and lack of guidelines for standard treatment, we report on this case to share our experience with management and treatment outcome.


Assuntos
Seios Paranasais , Sarcoma Sinovial , Feminino , Humanos , Sarcoma Sinovial/diagnóstico por imagem , Sarcoma Sinovial/cirurgia , Pescoço , Resultado do Tratamento , Cabeça/patologia
14.
Comput Biol Med ; 164: 107278, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37478713

RESUMO

Blood flow in stenosed arteries is a common cause of cardiovascular diseases, leading to serious health problems. The present study aims to investigate the unsteady Womersley blood flow in a stenosed, porous saturated artery under the influence of acceleration and magnetic fields. The study utilizes a Carreau constitutive equation to model blood rheology and employs the finite difference technique to compute the governing equations under the assumption of unsteady, unidirectional, and laminar flow. The importance of this study lies in its potential to provide a better understanding of the complex behavior of hemodynamic flow in the presence of external fields and porous media, which has significant implications for the control and management of cardiovascular diseases. In particular, the study analyses the impacts of non-dimensional parameters, such as magnetic field, channel permeability, acceleration field, Weissenberg number, and stenosis amplitude, on critical flow variables, such as velocity, resistivity, wall shear stress, and flow rate. Our calculations suggest that a magnetic field is an effective instrument for regulating hemodynamic flow because it increases resistance by up to 8.31% while decreasing flow by up to 8.44%. Channel permeability, on the other hand, improves blood velocity by up to 33.35% while eliminating resistance by up to 23.43%. Furthermore, greater acceleration fields decrease resistivity while increasing velocity, flow rate, and wall shear stress. Additionally, the severity of the stenosis and the Weissenberg number substantially affect flow factors. By raising the stenosis amplitude, resistivity rises, and other flow characteristics diminish, whereas modifying the Weissenberg number causes the reverse effect.


Assuntos
Doenças Cardiovasculares , Humanos , Porosidade , Constrição Patológica , Simulação por Computador , Hemodinâmica/fisiologia , Artérias , Campos Magnéticos , Aceleração , Estresse Mecânico , Modelos Cardiovasculares , Velocidade do Fluxo Sanguíneo/fisiologia
15.
Medicine (Baltimore) ; 102(22): e33793, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37266647

RESUMO

Malaria is a major health problem in Southwestern Saudi Arabia. This study aimed to measure the level of community understanding of malaria transmission, protection, and treatment. A questionnaire-based cross-sectional study enrolled 1070 participants from 2 districts with different malaria prevalence rates in Jazan Province. The response rate was 97.27%. Of the 1070 total; 754 (70.5%) had heard about malaria. Sixty-seven percentage know that fever was the main symptom. Approximately 59.8% did not know that stagnant water is one of the most important locations for mosquito breeding. Nevertheless, we found that 50% of the participants knew that mosquitoes bite at night and 96.9% confirmed that mosquitoes did not bite during the day. The most effective sources of information were distributed leaflets (41.8%) and video awareness (31.9%). The most significant factors affecting participants knowledge were gender, residence, family members, income, and education (P < .05). Knowledge levels were satisfactory in this study, and the majority of participants exhibited adequate attitudes and practices related to malaria prevention. However, knowledge differences were observed with regard to the place of residence. Greater emphasis should be directed towards education programs in malaria-endemic areas to ensure complete eradication of malaria.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Malária , Animais , Humanos , Estudos Transversais , Malária/epidemiologia , Malária/prevenção & controle , Inquéritos e Questionários , Habitação
16.
Ecancermedicalscience ; 17: 1545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377680

RESUMO

Objective: To investigate the compliance and clinical efficacy of vaginal dilators (VDs) as an educational intervention in patients receiving pelvic radiation therapy (RT) for endometrial and cervical malignancies. Material and methods: This is a single institution, retrospective chart review. Patients undergoing pelvic RT for endometrial or cervical cancer at our center were educated about the use of a VD starting 1 month after completion of RT. The patients were assessed after 3 months of prescribing VD. The demographic details and physical examination findings were extracted from medical records. Results: We identified 54 female patients at our institution during the 6-month duration. The median mean age of patients was 54 ± 9.9 years. Twenty-four (44.4%) had endometrial cancers and 30 (55.6%) were diagnosed with cervical cancers. All patients received external beam RT, 38 (70.4%) received a dose of 45 Gy, and 16 (29.6%) patients received 50.4 Gy. Brachytherapy was also received by all patients, 28 (51.9%) received 5 Gy × 2 fractions, 4 (7.4%) received 7 Gy × 3 fractions and 22 (40.7%) received 8 Gy × 3 fractions. The compliance with VD use was 36 (66.6%) patients. Twenty-two (40.7%) used 2-3 times a week, 8 (14.8%) used <2 times per week and 6 (11.9%) used only once a month, and 18 (33.3%) did not use the VD post-treatment. Per vaginal (PV) examination findings of the patient's vagina with normal mucosa were evaluated in 32 (59.3%) and adhesions were found in 20 (37.0%) and 2 (3.7%) were unable to examine due to dense adhesions. During examination 12 (22.2%) had bleeding PV, however, the majority of the patients, 42 (77.8%) experienced no bleeding PV. Out of the 36 patients who used a VD, it was found to be efficacious in 29 (80.6%) of patients. Upon stratification of efficacy with a frequency of VD, 72.4% (n = 21) efficacy was seen in patients using frequent VD as prescribed 2-3 times per week. Conclusion: The compliance and efficacy of VD use after radiation to pelvic in cervical and endometrial cancers at 3 months follow-up were found to be 66.6% and 80.6%, respectively. This shows that VD therapy is an effective interventional tool and patients should receive specialist education about vaginal stenosis as toxicity at the outset of treatment.

17.
Langmuir ; 39(20): 7109-7121, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37156095

RESUMO

One of the main objectives in wastewater treatment and sustainable energy production is to find photocatalysts that are favorably efficient and cost-effective. Transition-metal dichalcogenides (TMDs) are promising photocatalytic materials; out of all, MoS2 is extensively studied as a cocatalyst in the TMD library due to its exceptional photocatalytic activity for the degradation of organic dyes due to its distinctive morphology, adequate optical absorption, and rich active sites. However, sulfur ions on the active edges facilitate the catalytic activity of MoS2. On the basal planes, sulfur ions are catalytically inactive. Injecting metal atoms into the MoS2 lattice is a handy approach for triggering the surface of the basal planes and enriching catalytically active sites. Effective band gap engineering, sulfur edges, and improved optical absorption of Mn-doped MoS2 nanostructures are promising for improving their charge separation and photostimulated dye degradation activity. The percentage of dye degradation of MB under visible-light irradiations was found to be 89.87 and 100% for pristine and 20% Mn-doped MoS2 in 150 and 90 min, respectively. However, the degradation of MB dye was increased when the doping concentration in MoS2 increased from 5 to 20%. The kinetic study showed that the first-order kinetic model described the photodegradation mechanism well. After four cycles, the 20% Mn-doped MoS2 catalysts maintained comparable catalytic efficacy, indicating its excellent stability. The results demonstrated that the Mn-doped MoS2 nanostructures exhibit exceptional visible-light-driven photocatalytic activity and could perform well as a catalyst for industrial wastewater treatment.

18.
ACS Appl Mater Interfaces ; 15(10): 13299-13306, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36856371

RESUMO

The existence of a novel phenomenon, such as the metal-insulator transition (MIT) in two-dimensional (2D) systems, affords emerging functional properties that provide new aspects for future electronics and optoelectronics. Here, we report the observation of the MIT in black phosphorus field effect transistors by tuning the carrier density (n) controlled by back-gate bias. We find that the conductivity follows an n dependence as σ(n) ∝ nα with α ∼ 1, which indicates the presence of screened Coulomb impurity scattering at high carrier densities in the temperature range of 10-300 K. As n decreases, the screened Coulomb impurity scattering breaks down, developing strong charge density inhomogeneity leading to a percolation-based transition at the critical carrier density (nC). At low carrier densities (n < nC), the system is in the insulating regime, which is expressed by Mott variable range hopping that demonstrates the role of disorder in the system. In addition, the extracted average values of critical exponent δ are ∼1.29 ± 0.01 and ∼1.14 ± 0.01 for devices A and B, respectively, consistent with the 2D percolation exponent of 4/3, confirming the 2D percolation-based MIT in BP devices. Our findings strongly suggest that the 2D MIT observed in BP is a classical percolation-based transition caused by charge inhomogeneity induced by screened Coulomb charge impurity scattering around a transition point controlled by n through back-gate bias.

19.
J Chromatogr A ; 1694: 463926, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36948087

RESUMO

Stimuli-responsive block copolymers have exhibited their feasibility for drug delivery and analysis of biomolecules. However, study of the electrophoretic behavior of antibiotics by open tubular capillary electrochromatography (OT-CEC) based on smart block copolymers coatings is still a substantial challenge. Herein, we reported an OT-CEC protocol for analysis of cephalosporin antibiotics with pH-responsive block copolymers as coatings. By using the reversible addition-fragmentation chain-transfers radical polymerisation technique, the smart poly(styrene-maleic anhydride-acrylic acid) (P(St-MAn-AA)) was synthesized and subsequently chemical bonded onto the inner walls of amino-grafted capillaries. The pH induced changes in the stretch/curl states of P(St-MAn-AA) chains were used to generate an adjustable hydrophobic/hydrophilic interaction and hydrogen bonds between the polymer coatings and the analytes. The OT-CEC performance was evaluated by varying the monomer ratios, polymer coating amounts and layers, buffer concentrations and pH values. Baseline separation of the three-test antibiotics was achieved at pH 8.0. The proposed OT-CEC technique was further applied to the determination of rat serum antibiotics in the metabolic processes. The present work demonstrates an enhancement in antibiotics separation efficiency, and shows a great potential for the preparation of stimuli-responsive block copolymers coatings and in OT-CEC analysis of real samples in living bio-systems.


Assuntos
Eletrocromatografia Capilar , Concentração de Íons de Hidrogênio , Polímeros/química , Estrutura Molecular , Cefalosporinas/química , Cefalosporinas/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Animais , Ratos
20.
Comput Biol Med ; 153: 106386, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36587569

RESUMO

It is hypothesized that gliding bacteria move by producing waves on their own surface and leave an adhesive slime trail. Slime is basically a viscoelastic slippery material. Based on these observations, we use a mathematical model (of undulating sheet) to examine the locomotion of gliding bacteria over a layer of non-Newtonian slime. The constitutive equations of FENE-P model are employed to characterize the rheological behavior of the non-Newtonian slime. Moreover, substratum beneath the slime is approximated by a multi-sinusoidal sheet. A hybrid computational technique to solve the second order DE with a system of algebraic equations is presented. The speed of organism, flow rate and energy loss at larger values of the involved parameters are simulated using bvp5c in conjunction with a modified Newton-Raphson technique (MNRT). The comparison of soft and rigid substrate, slip and no-slip boundary conditions, Newtonian and non-Newtonian slime is displayed in several figures. Streamlines pattern and velocity of the slime are also drawn for the realistic pairs of speed and flow rate and are thoroughly explained.


Assuntos
Bactérias , Locomoção , Modelos Teóricos
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