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1.
J Chem Phys ; 160(2)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38193555

RESUMEN

We present a comprehensive study using dissipative particle dynamics simulations to investigate phase separation kinetics (PSK) in three-dimensional (3d) polymeric fluids under random photo-illumination. We consider two scenarios: polymer blends with active radicals at one end of each immiscible chain and block copolymer (BCP) melts with photosensitive bonds linking incompatible blocks. The phase separation (PS) is induced by temperature quench of the initial homogeneously mixed system. Simultaneously, the system experiences random photo-illumination, simulated by two concurrent random events: (a) the recombination of active radicals in polymer blends and (b) the breaking of photosensitive bonds in BCP chains. Variations in the bond-breaking probability, Pb, mimic the change in light intensity. The length scale follows power law growth, R(t) ∼ tϕ, where ϕ represents the growth exponent. Increasing Pb results in a gradual transition in growth kinetics from micro-PS to macro-PS, accompanied by corresponding transition probabilities for both systems. Micro-PSK dominates the evolution process at low Pb values. The scaling functions exhibit data overlap for most scaled distances, indicating the statistical self-similarity of evolving patterns. Our study enhances the understanding of PSK in polymeric fluids, revealing the impact of photosensitive bonds and active radicals. Furthermore, it suggests the potential for designing novel polymeric materials with desired properties.

2.
J Shoulder Elbow Surg ; 33(3): e109-e115, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37898417

RESUMEN

BACKGROUND: Glenohumeral osteoarthritis is one of the most common causes of shoulder pain. As such, the American Academy of Orthopaedic Surgeons (AAOS) has developed clinical practice guidelines (CPGs) to address the management of glenohumeral osteoarthritis. These CPG recommendations stem from the findings of randomized controlled trials (RCTs), which have been shown to influence clinical decision making and health policy. Therefore, it is essential that trial outcomes, including harms data (ie, adverse events), are adequately reported. We intend to evaluate the reporting quality of harms-related data in orthopedic literature specifically relating to AAOS CPG recommendations on the management of glenohumeral osteoarthritis. METHODS: We adhered to the Preferred Reporting Items for Systematic Reviews (PRISMA) as well as guidance for reporting meta-research. The AAOS CPGs for glenohumeral osteoarthritis were obtained from orthoguidelines.org, and 2 authors independently screened the guidelines for the RCTs referenced. A total of 14 studies were identified. Data were extracted from the 14 included studies independently by the same 2 authors. Adherence to the Consolidated Standards of Reporting Trials (CONSORT) Extension for Harms Checklist was assessed using an 18-item scoring chart, with 1 point being awarded for meeting a checklist item and 0 points being awarded for not meeting a checklist item. Descriptive statistics, such as frequencies, percentages, and 95% confidence intervals were used to summarize RCT adherence to the CONSORT checklist. RESULTS: The average score among the studies included was 7.36/18 items (39% adherence). No study adhered to all criteria, with the highest-performing study meeting 11 of 18 items (58%) and the lowest meeting 3 of 18 items (16%). A positive correlation between checklist score and year of publication was observed, with studies published more recently receiving a higher score on the CONSORT checklist (P < .05). Studies that disclosed funding information received a higher score than those that did not (P < .05), but there was no significant difference when the different funding sources were compared. Finally, double-blinded studies scored higher on the checklist than those with lower levels of blinding (single or no blinding, P < .05). CONCLUSION: Adverse events are poorly reported amongst RCTs cited as supporting evidence for AAOS Management of Glenohumeral Osteoarthritis CPGs, evidenced by a CONSORT checklist compliance rate of only 41% in this study. We recommend the development of an updated checklist with information that makes it easier for authors to recognize, evaluate, and report on harms data. Additionally, we encourage authors to include information about adverse events or negative outcomes in the abstract.


Asunto(s)
Ortopedia , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Lista de Verificación , Cirujanos Ortopédicos , Guías de Práctica Clínica como Asunto , Articulación del Hombro/cirugía , Osteoartritis/cirugía
3.
J Chem Phys ; 159(20)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37991159

RESUMEN

We present the phase separation dynamics of a binary (AB), simple fluid (SF), and amphiphilic polymer (AP) mixture using dissipative particle dynamics simulation at d = 3. We study the effect of different AP topologies, including block copolymers, ring block copolymers (RCP), and miktoarm star polymers, on the evolution morphologies, dynamic scaling functions, and length scale of the AB mixture. Our results demonstrate that the presence of APs leads to significantly different evolution morphologies in SF. However, the deviation from dynamical scaling is prominent, mainly for RCP. Typically, the characteristic length scale for SF follows the power law R(t) ∼ tϕ, where ϕ is the growth exponent. In the presence of high AP, we observe diffusive growth (ϕ → 1/3) at early times, followed by saturation in length scale (ϕ → 0) at late times. The extent of saturation varies with constraints imposed on the APs, such as topology, composition ratio, chain length, and stiffness. At lower composition ratios, the system exhibits inertial hydrodynamic growth (ϕ → 2/3) at asymptotic times without clearly exhibiting the viscous hydrodynamic regime (ϕ → 1) at earlier times in our simulations. Our results firmly establish the existence of hydrodynamic growth regimes in low surfactant-influenced phase separation kinetics of binary fluids and settle the related ambiguity in d = 3 systems.

4.
Soft Matter ; 19(34): 6433-6445, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37403605

RESUMEN

This paper investigates the phase separation kinetics of ternary fluid mixtures composed of a polymeric component (C) and two simple fluids (A and B) using dissipative particle dynamics simulations with a system dimensionality of d = 3. We model the affinities between the components to enable the settling of the polymeric component at the interface of fluids A and B. Thus, the system evolves to form polymer coated morphologies, enabling alteration of the fluids' interfacial properties. This manipulation can be utilized across various disciplines, such as the stabilization of emulsions and foams, rheological control, biomimetic design, and surface modification. We probe the effects of various parameters, such as the polymeric concentration, chain stiffness, and length, on the phase separation kinetics of the system. The simulation results show that changes in the concentration of flexible polymers exhibit perfect dynamic scaling for coated morphologies. The growth rate decreases as the polymeric composition is increased due to reduced surface tension and restricted connectivity between A- and B-rich clusters. Variations in the polymer chain rigidity at fixed composition ratios and degrees of polymerization slow the evolution kinetics of AB fluids marginally, although the effect is more pronounced for perfectly rigid chains. Whereas flexible polymer chain lengths at fixed composition ratios slow down the segregation kinetics of AB fluids slightly, varying the chain lengths of perfectly rigid polymers leads to a significant deviation in the length scale and dynamic scaling for the evolved coated morphologies. The characteristic length scale follows a power-law growth with a growth exponent ϕ that shows a crossover from the viscous to the inertial hydrodynamic regime, where the values of ϕ depend on the constraints imposed on the system.

5.
Sultan Qaboos Univ Med J ; 23(Spec Iss): 59-62, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38161754

RESUMEN

Appearance of unexpected masses in the chambers of the heart during cardiac surgery can be intriguing. We report the case of a mass in the left ventricle that appeared at the time of separation from cardiopulmonary bypass in a child after a complex intracardiac repair. The child presented for surgery to a tertiary care hospital in Muscat, Oman, in 2022. Prior to the surgical repair the mass was not appreciated by echocardiography. An intraventricular baffle was used to divert left ventricular blood flow towards the outflow tract, after which an intraventricular "mass" was observed. Intraoperative transoesophageal echocardiography identified the mass as a portion of the interventricular septum that was located between the inlet and outlet ventricular septal defects.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Defectos del Tabique Interventricular , Niño , Humanos , Corazón , Defectos del Tabique Interventricular/diagnóstico por imagen , Defectos del Tabique Interventricular/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Ecocardiografía
8.
Phys Sportsmed ; 49(3): 271-277, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34010095

RESUMEN

Background: Achilles tendon ruptures are devastating injuries for National Basketball Association (NBA) players: prior studies have demonstrated decreased performance following return-to-play, but none have evaluated the effect of injury on rate-adjusted contextual statistics to assess the true change in performance. Additionally, there exists a paucity of data on the independent impact on defensive performance following return.Hypothesis: Compared to both control-matched peers and preoperative careers, we hypothesize that player production based on rate-adjusted contextual statistics will significantly decline following Achilles tendon rupture.Study design: Retrospective Cohort StudyMethods: Publicly available NBA injury data on Achilles tendon rupture were reviewed from the 1996 -1997 to the 2016-2017 seasons. Controls were matched based on height, position, age, and rate-adjusted statistics. Extracted data included Value over Replacement Player Rating, Box Plus-Minus, Win Shares, offensive rating, defensive rating, and time to return-to-play, and was collected for the season before and two seasons following injury.Results: Twenty-five NBA players with surgically treated complete Achilles ruptures met inclusion and exclusion criteria. The return-to-play rate from Achilles tendon ruptures from 1996-1997 to 2016-2017 was 80%, with a mean recovery period of 311.0 ± 100.9 days. After 2 years, performance significantly declined for Value over Replacement Player Rating, Box Plus-Minus, and offensive rating compared to controls and cases. However, there was no significant effect on defensive rating (P = 0.38). After two seasons, returning players had a Value over Replacement Player Rating that was 24.1% below pre-injury levels, contributed 1.4 fewer points per 100 possessions by Box Plus-Minus, and yielded 2.4 fewer wins by Win Shares.Conclusions: Achilles tendon rupture results in significant decreases in offensive production and career longevity. The injury does not have a significant impact on defensive production.Clinical relevance: Achilles tendon ruptures significantly affect basketball players ability to return-to-play, and their in-game performance.Level of evidence: 3.


Asunto(s)
Tendón Calcáneo , Traumatismos en Atletas/epidemiología , Rendimiento Atlético , Baloncesto , Volver al Deporte , Tendón Calcáneo/lesiones , Baloncesto/lesiones , Humanos , Estudios Retrospectivos , Rotura
9.
Soft Matter ; 17(7): 1802-1813, 2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33399613

RESUMEN

Using a dissipative particle dynamics (DPD) simulation method, we study the phase separation dynamics in block copolymer (BCP) melts in d = 3, subjected to external stimuli such as light. An initial homogeneous BCP melt is rapidly quenched to a temperature T < Tc, where Tc is the critical temperature. We then allow the system to undergo alternate light "on" and "off" cycles. An on-cycle breaks the stimuli-sensitive bonds connecting both the blocks A and B in the BCP melt, and during the off-cycle, the broken bonds recombine. By simulating the effect of light, we isolate scenarios where phase separation begins with the light off (set 1); the cooperative interactions within the system allow it to undergo microphase separation. When the phase separation starts with the light on (set 2), the system undergoes macrophase separation due to bond breaking. Here, we report the role of alternate cycles on domain morphology by varying the bond-breaking probability for both set 1 and set 2, respectively. We observe that the scaling functions depend upon the conditions mentioned above that change the time scale of the evolving morphologies in various cycles. However, in all the cases, the average domain size respects the power-law growth: R(t) ∼tφ at late times, where φ is the dynamic growth exponent. After a short-lived diffusive growth (φ∼ 1/3) at early times, φ illustrates a crossover from the viscous hydrodynamic (φ∼ 1) to the inertial hydrodynamic (φ∼ 2/3) regimes at late times.

10.
Environ Sci Pollut Res Int ; 26(22): 22464-22471, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31161542

RESUMEN

A field experiment was conducted to study the persistence and dissipation pattern of a new molecule tetraniliprole on tomato fruits and soil. Tetraniliprole was sprayed at the rate of 60 g a.i. ha-1 and 120 g a.i. ha-1on the tomato crop. Tomato fruit samples were analyzed as per the method described by Bosta and Nageswara (Asian J Res Chem 8:383-388, 2015). The residues of tetraniliprole and its metabolite chinazolinon were estimated on HPLC equipped with RP C18 column and photo diode array detector. Initial deposits of tetraniliprole were 0.865 and 1.747 mg kg-1 on fruits and 0.092 and 0.177 mg kg-1 in the soil, respectively, from the two treatments at the rate 60 g a.i. ha-1 and 120 g a.i. ha-1. The residues on fruits dissipated to half in 2.7 and 3.49 days, respectively. Based on the persistence studies, a waiting period of 15 days is suggested on tomato fruit from consumer's safety point of view. The pesticide residues, left to a variable extent in the tomato after harvesting, are beyond the control of consumers and have deleterious effects on human health; hence, their residues reduction by various culinary processes were highlighted. Treated tomato fruit samples collected at 1, 3, and 5 days after application were also subjected to common household practices. Washing of tomato fruits by tap, lukewarm, and saline water reduce tetraniliprole residues up to 37.63, 44.67, and 61.49%, respectively. Microwave cooking of tomato provided >12% better relief from tetraniliprole residues in comparison with open pan cooking of 72.21%. Chinazolinon residues, a metabolite of tetraniliprole, were not detected in any analyzed processed tomato fruit sample.


Asunto(s)
Frutas/química , Residuos de Plaguicidas/análisis , Suelo/química , Solanum lycopersicum/metabolismo , Cromatografía Líquida de Alta Presión , Culinaria , Semivida , Humanos , India , Insecticidas/análisis , Solanum lycopersicum/química
11.
Environ Sci Pollut Res Int ; 25(27): 27594-27605, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30054838

RESUMEN

The persistence of chlorpyrifos, fluopyram, and tebuconazole was estimated in green pods, matured seeds, and soil of French beans using dispersive QuEChERS. Three foliar applications each of chlorpyrifos and a combination fungicide fluopyram + tebuconazole (Luna experience, 400 SC) were applied at 600 and 125 + 125 as a standard dose and 1200 and 250 + 250 g a.i. ha-1 as a double dose, respectively, were applied at an interval of 10 days and treated pods were picked up at regular intervals. Dried mature seeds and soil were also monitored at harvest. The initial deposits of chlorpyrifos on bean pods were 3.083 and 6.017 mg kg-1 with a half-life of 1.86 and 2.29 days, at respective doses. Foliar application of a combi product Luna experience yielded 3.396 and 5.772 mg kg-1 residues of fluopyram and 3.613 and 5.887 mg kg-1 of tebuconazole in green pods at standard and double dose with almost same half-lives of 3.4 and 3.8-3.9 days. Residues declined below the limit of quantitation (LOQ) of 0.05 mg kg-1 in green beans after 15 and 25 days after the application of double dose of chlorpyrifos and Luna experience, respectively. However, the residues in dry bean seeds and soil reached below the LOQ of 0.05 mg kg-1 at the time of harvest. A pre-harvest interval of 5, 10, and 7 days has been proposed for chlorpyrifos, fluopyram, and tebuconazole, respectively, in beans. HQ < 1 and TMDI < MPI in all test chemicals. Hence, it was concluded that a waiting period of 5 days for chlorpyrifos and 7-10 days in Luna experience will be safer to consumers. This data generated will be useful for regulatory agency for fixing MRLs.


Asunto(s)
Benzamidas/análisis , Cloropirifos/análisis , Fungicidas Industriales/análisis , Residuos de Plaguicidas/análisis , Phaseolus/crecimiento & desarrollo , Piridinas/análisis , Contaminantes del Suelo/análisis , Triazoles/análisis , Benzamidas/toxicidad , Cloropirifos/toxicidad , Fungicidas Industriales/toxicidad , Semivida , India , Residuos de Plaguicidas/toxicidad , Phaseolus/química , Piridinas/toxicidad , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/toxicidad , Triazoles/toxicidad
12.
Contemp Clin Dent ; 4(1): 54-61, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23853453

RESUMEN

AIM: The aim of this study was to evaluate the effects of hyaluronan (HA) and chlorhexidine (CHX) gels as adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis. MATERIALS AND METHODS: Sixty patients within the age group of 30-65 years recruited to participate in the study were randomly equally divided into three groups. Complete SRP and subgingival debridement were performed within 6 h in all the patients. For control (Group I) patients, SRP was the only treatment modality given; for Group II and III patients, at least 8 teeth with 4-8 mm probing pocket depth (PPD) were selected for subgingival application of HA gel and CHX gel, respectively. Clinical periodontal parameters such as gingival index, PPD, and clinical attachment level (CAL) were recorded at baseline and 3 months, whereas plaque index was recorded at baseline, 1 month, and 3 months. For measuring systemic/hematological parameters, blood samples for laboratory tests for total leucocyte count (TLC), differential leucocyte count (DLC), and C-reactive protein (CRP) were obtained using standard 2-mL syringe from each subject in all the three groups at baseline, 24 h, and on the 1 month and 3 months post-baseline. RESULTS: In all the three groups, a significant reduction in PPD and gain in CAL were observed between baseline and 3 months follow-up (P< 0.05); however, at 3 months, change in PPD and CAL was more in Group II than Group III, but the difference was non-significant, and Group I (control) showed less changes in PPD and CAL than both experimental groups. Only one patient revealed positive value for CRP at baseline only, and hence could not be statistically analyzed. In all the three groups, the peak values for TLC count were observed at 24 h. At 1-month and 3-month intervals, a significant improvement in TLC and DLC counts was observed among the experimental (HA gel/SRP and Xan-CHX gel) groups as compared to control group (SRP alone).

13.
J Sep Sci ; 27(4): 275-83, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15334914

RESUMEN

The growing importance of analyzing the human genome to detect hereditary and infectious diseases associated with specific DNA sequences has motivated us to develop automated devices to integrate sample preparation, real-time PCR, and microchannel electrophoresis (MCE). In this report, we present results from an optimized compact system capable of processing a raw sample of blood, extracting the DNA, and performing a multiplexed PCR reaction. Finally, an innovative electrophoretic separation was performed on the post-PCR products using a unique MCE system. The sample preparation system extracted and lysed white blood cells (WBC) from whole blood, producing DNA of sufficient quantity and quality for a polymerase chain reaction (PCR). Separation of multiple amplicons was achieved in a microfabricated channel 30 microm x 100 microm in cross section and 85 mm in length filled with a replaceable methyl cellulose matrix operated under denaturing conditions at 50 degrees C. By incorporating fluorescent-labeled primers in the PCR, the amplicons were identified by a two-color (multiplexed) fluorescence detection system. Two base-pair resolution of single-stranded DNA (PCR products) was achieved. We believe that this integrated system provides a unique solution for DNA analysis.


Asunto(s)
ADN/aislamiento & purificación , Genoma Humano , Automatización , Secuencia de Bases , ADN/sangre , ADN/genética , Cartilla de ADN , Electroforesis/instrumentación , Electroforesis/métodos , Diseño de Equipo , Humanos , Miniaturización/métodos , Reacción en Cadena de la Polimerasa
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