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1.
Environ Res ; 249: 118320, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38331148

RESUMEN

In a global context, trace element pollution assessment in complex multi-aquifer groundwater systems is important, considering the growing concerns about water resource quality and sustainability worldwide. This research addresses multiple objectives by integrating spatial, chemometric, and indexical study approaches, for assessing trace element pollution in the multi-aquifer groundwater system of the Al-Hassa Oasis, Saudi Arabia. Groundwater sampling and analysis followed standard methods. For this purpose, the research employed internationally recognized protocols for groundwater sampling and analysis, including standardized techniques outlined by regulatory bodies such as the United States Environmental Protection Agency (USEPA) and the World Health Organization (WHO). Average values revealed that Cr (0.041) and Fe (2.312) concentrations surpassed the recommended limits for drinking water quality, posing serious threats to groundwater usability by humans. The trace elemental concentrations were ranked as: Li < Mn < Co < As < Mo < Zn < Al < Ba < Se < V < Ni < Cr < Cu < B < Fe < Sr. Various metal(loid) pollution indices, including degree of contamination, heavy metal evaluation index, heavy metal pollution index, and modified heavy metal index, indicated low levels of groundwater pollution. Similarly, low values of water pollution index and weighted arithmetic water quality index were observed for all groundwater points, signifying excellent groundwater quality for drinking and domestic purposes. Spatial distribution analysis showed diverse groundwater quality across the study area, with the eastern and western parts displaying a less desirable quality, while the northern has the best, making water users in the former more vulnerable to potential pollution effects. Thus, the zonation maps hinted the necessity for groundwater quality enhancement from the western to the northern parts. Chemometric analysis identified both human activities and geogenic factors as contributors to groundwater pollution, with human activities found to have more significant impacts. This research provides the scientific basis and insights for protecting the groundwater system and ensuring efficient water management.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Oligoelementos , Contaminantes Químicos del Agua , Agua Subterránea/análisis , Agua Subterránea/química , Arabia Saudita , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Oligoelementos/análisis
2.
Sensors (Basel) ; 24(4)2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38400361

RESUMEN

Poor alertness levels and related changes in cognitive efficiency are common when performing monotonous tasks such as extended driving. Recent studies have investigated driver alertness decrement and possible strategies for modulating alertness with the goal of improving reaction times to safety critical events. However, most studies rely on subjective measures in assessing alertness changes, while the use of olfactory stimuli, which are known to be strong modulators of cognitive states, has not been commensurately explored in driving alertness settings. To address this gap, in the present study we investigated the effectiveness of olfactory stimuli in modulating the alertness state of drivers and explored the utility of electroencephalography (EEG) in developing objective brain-based tools for assessing the resulting changes in cortical activity. Olfactory stimulation induced a significant differential effect on braking reaction time. The corresponding effect to the cortical activity was characterized using EEG-derived metrics and the devised machine learning framework yielded a high discriminating accuracy (92.1%). Furthermore, neural activity in the alpha frequency band was found to be significantly associated with the observed drivers' behavioral changes. Overall, our results demonstrate the potential of olfactory stimuli to modulate the alertness state and the efficiency of EEG in objectively assessing the resulting cognitive changes.


Asunto(s)
Conducción de Automóvil , Dispositivos Electrónicos Vestibles , Conducción de Automóvil/psicología , Atención/fisiología , Tiempo de Reacción/fisiología , Electroencefalografía/métodos
3.
Arch Microbiol ; 204(12): 707, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36378329

RESUMEN

Microbial adhesion and transport are significantly influenced by their hydrophobicity. Various domains, such as biofouling, bioremediation, wastewater treatment, oil recovery, pathogenesis, implant infections, and several other microbial disciplines, make use of hydrophobicity assessment. One easy assay for assessing the microbial surface hydrophobicity is the microbial adhesion to hydrocarbons (MATH) test which works on the differential partitioning of microbes at a hydrocarbon-aqueous interface. Unfortunately, a standard protocol for this test is still unavailable, even though it has been widely studied and it is known that the results are sensitive to the operating parameters used. This study has been envisaged to investigate the effects of variations in the MATH test parameters on the hydrophobicity results. For this purpose, six different test parameters (vortex duration, phase separation period, hydrocarbon-aqueous phase volume ratio, hydrocarbon selection, absorbance wavelength, and suspension medium) were varied. Four different Gram-negative bacteria were used for experimentation. It was observed that except for phase separation period, all other test parameters significantly influenced the hydrophobicity results. Furthermore, the hydrocarbon saturation of the suspension medium was a critical factor for growth medium suspensions. This study is expected to guide researchers in selecting the appropriate values of test parameters for MATH tests and enhance our understanding of this technique and pave the way for developing a standardized protocol.


Asunto(s)
Adhesión Bacteriana , Hidrocarburos , Interacciones Hidrofóbicas e Hidrofílicas , Bacterias , Biodegradación Ambiental , Agua
4.
Langmuir ; 34(40): 11925-11932, 2018 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-30208711

RESUMEN

Silicon oxide substrates underwent gas-phase functionalization with various aminosilanes, and the resulting surfaces were evaluated for their suitability as a solid support for solid phase peptide synthesis (SPPS). APTES (3-aminopropyltriethoxysilane), APDEMS (3-aminopropyldiethoxymethylsilane), and APDIPES (3-aminopropyldiisopropylethoxysilane) were individually applied to thermal oxide-terminated silicon substrates via gas-phase deposition. Coated surfaces were characterized by spectroscopic ellipsometry (SE), contact angle goniometry, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and spectrophotometry. Model oligopeptides with 16 residues were synthesized on the amino surfaces, and the chemical stabilities of the resulting surfaces were evaluated against a stringent side chain deprotection (SCD) step, which contained trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFMSA). Functionalized surface thickness loss during SCD was most acute for APDIPES and the observed relative stability order was APTES > APDEMS > APDIPES. Amino surfaces were evaluated for compatibility with stepwise peptide synthesis where complete deprotection and coupling cycles are paramount. Model trimer syntheses indicated that routine capping of unreacted amines with acetic anhydride significantly increased purity as measured by MALDI-MS. An inverse correlation between the amine loading density and peptide purity was observed. In general, peptide purity was highest for the lowest amine density APDIPES surface.

5.
Environ Sci Pollut Res Int ; 31(27): 39077-39097, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38102425

RESUMEN

The concept of "smart rotor" is an evolving advancement in wind turbine which enables an intelligent active flow control in rotor. The deformable trailing edge flap (DTEF) is a part of smart rotor concept which implements a customized active load control. The trailing edge flap actuator effectively replaces the tedious blade pitch actuation and conserves the actuation energy required for pitching the entire blade. The DTEFs require a fast computing, anticipatory controller for optimally tuning the flap angle with minimal power compromise. This work analyzes the performance of advanced control strategies like model predictive control (MPC), adaptive MRAC control, and DQ controllers. The MRAC controller is found to reduce the fatigue stress by 40% and the MPC controller damps up to 70% more efficiently than the typical feedback controller. The control strategies are aided by the LiDAR-based preview wind data for the active manipulation of trailing edge flap angle ( θ flap ) control. The validation of proposed controller is done using power analysis curve and the component fatigue lifetime analysis using MLIFE software. The above analyses are done in NREL Onshore 5-MW FAST wind turbine model which could be interfaced with MATLAB with modified AeroDyn code for active flap deflection.


Asunto(s)
Viento , Modelos Teóricos
6.
Org Lett ; 25(51): 9170-9175, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38100382

RESUMEN

We report herein an organocatalyzed enantioselective spirocyclization strategy to access valuable C2-spiroindoline scaffolds bearing a quaternary stereocenter via an aza-Michael addition reaction, wherein the acid additive plays the role of dual functionality. The substrates for this key step were put together by an exo-selective, Pd-catalyzed γ-arylation of silyldienol ethers of the corresponding cyclohexenones. A close alliance between a low catalyst loading and a slow reaction rate yields C2-spiroindolines with good enantioselectivity.

7.
Ann Oper Res ; : 1-20, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-37361100

RESUMEN

Due to the COVID-19 outbreak, industries have gained a thrust on contactless processing for computing technologies and industrial automation. Cloud of Things (CoT) is one of the emerging computing technologies for such applications. CoT combines the most emerging cloud computing and the Internet of Things. The development in industrial automation made them highly interdependent because the cloud computing works like a backbone in IoT technology. This supports the data storage, analytics, processing, commercial application development, deployment, and security compliances. Now amalgamation of cloud technologies with IoT is making utilities more useful, smart, service-oriented, and secure application for sustainable development of industrial processes. As the pandemic has increased access to computing utilities remotely, cyber-attacks have been increased exponentially. This paper reviews the CoT's contribution to industrial automation and the various security features provided by different tools and applications used for the circular economy. The in-depth analysis of security threats, availability of different features corresponding the security issues in traditional and non-traditional CoT platforms used in industrial automation have been analysed. The security issues and challenges faced by IIoT and AIoT in industrial automation have also been addressed.

8.
Environ Sci Pollut Res Int ; 30(60): 125328-125346, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37535288

RESUMEN

Nano-additives are being employed in successive generations of biodiesels to increase the performance characteristics and output of diesel engines. In this study, the impact of mixing carbon nanotubes (CNT) with three different generations of biodiesel in a diesel engine is assessed. With 100 ppm of CNT nanoparticles mixed together, pure biodiesels made from first-generation oil (soybean), second-generation oil (neem), and third-generation oil (Nannochloropsis oculata microalgae) are used for the analysis. With an engine load ranging from 0 to 100%, a one-cylinder, four-stroke, direct injection diesel engine is employed. The engine has a water-cooling system, a compression ratio of 17.5:1, and a fuel injection angle of 23° before TDC. The evaluated engines' improved performance and lower emissions serve as proof of the outcomes. The results are evidenced by the lower emissions and higher performance of the tested engines. The biodiesel containing CNT nanoparticles enhanced the cylinder pressure by 0.8-10.69%, the heat release rate (HRR) by 6.38-21.69%, and the brake thermal efficiency (BTE) by 0.32-1.62%. Subsequently, it reduced the brake-specific fuel consumption (BSFC) by 2.53-8.13%, the brake-specific energy consumption (BSEC) by 1.07-3.77%, the smoke opacity (BSN) by 6.26-12.85%, the particulate matter (PM) emissions by 11.04-18.33%, and the carbon dioxide (CO2) emissions by 2.53-8.14% at full engine load. However, an increase in 13.62-18.37% nitrogen emissions (NOx) emissions is also observed with the addition of CNT at 100% load. The investigation supports the use of CNT nano-additives in diesel engines for improved performance and reduced emissions.


Asunto(s)
Gasolina , Nanotubos de Carbono , Biocombustibles , Monóxido de Carbono/análisis , Emisiones de Vehículos
9.
Int Orthop ; 36(9): 1813-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22648556

RESUMEN

PURPOSE: Optimal positioning of acetabular components is crucial for maintaining stability of THA. Postoperative assessment of acetabular anteversion is a vital but difficult task. Various methods have been devised with good results for measuring anteversion on plain radiographs but these methods are either too complicated or require special objects like scientific calculators, special protectors, tables, etc. A new simplified method of measuring anteversion on plain radiographs was created based on basic geometry. METHODS: Anteversion of acetabular components was estimated on computer generated images of the acetabular cup by our method and compared with two previously established methods of Liaw and Pradhan. Measurement was done at 400 different positions of acetabular cup and compared with actual values. Another analysis was done after adding the femoral head to the acetabular component, thus obscuring some of the acetabular rim. RESULTS: Mean and standard deviation of error for our method was 0.77° ± 0.75° as compared to 0.93° ± 0.86° and 0.72° ± 0.68° for the methods of Liaw and Pardhan, respectively, with no significant differences from actual values. Maximal errors for our method, Liaw's and Pradhan's method were 3°, 4°, and 2.91°, respectively. On analysis, after the adding femoral head, there was a significant error of measurement with Liaw's method, while our method as well as Pardhan's remained accurate. All methods showed high inter- and intraobserver reliability. CONCLUSION: Our new simplified method of measuring acetabular anteversion on plain radiographs is acceptable in comparision to other established methods and requires only routinely used goniometer and calliper.


Asunto(s)
Acetábulo/diagnóstico por imagen , Artroplastia de Reemplazo de Cadera/métodos , Anteversión Ósea/diagnóstico , Luxación de la Cadera/diagnóstico , Prótesis de Cadera , Ajuste de Prótesis/métodos , Acetábulo/anatomía & histología , Humanos , Variaciones Dependientes del Observador , Complicaciones Posoperatorias/prevención & control , Radiografía , Reproducibilidad de los Resultados
10.
Injury ; 53(10): 3361-3364, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36031439

RESUMEN

INTRODUCTION: Open reduction and internal fixation of acetabular fracture is associated with significant blood loss. Although Tranexamic acid (TXA) infusion effectively reduces perioperative blood loss and transfusion requirements in elective orthopedic surgery, its efficacy in major orthopedic trauma surgery is controversial. MATERIAL AND METHODS: Sixty-three patients undergoing open reduction and internal fixation of acetabular fracture were randomized into either TXA (n = 36) or placebo (n = 27) group. TXA group received a bolus dose of TXA (10 mg/kg) 15 min prior to incision, followed by another similar dose after 3 h of surgery. The placebo group received the same volume of normal saline similarly. All patients were operated on by a single pelviacetabular surgeon with a uniform perioperative protocol. The intraoperative blood loss, drain output, the number of blood transfusions, postoperative hemoglobin (Hb) drop, and hematocrit (Hct) drop were calculated. RESULTS: Both groups were similar in relation to age, sex, BMI, preoperative Hb, the timing of surgery, fracture pattern, operative time, and surgical approaches. The mean postoperative Hb was 10.35 ± 1.36 gm% in TXA group and 9.74 ± 1.98 gm% in placebo group (p-value 0.158). There were no differences in intraoperative blood loss (438.11 ml vs. 442.81, p=.947), drain output (131.94 ml vs. 129.63, p=.870), and blood transfusion (8 patients vs. five patients, p=.719) between the groups. The drop in Hb and Hct in the postoperative period was also statistically not significant between the groups. CONCLUSION: There is no significant reduction in blood loss and blood transfusion with the use of intravenous Tranexamic acid in open reduction and internal fixation of acetabular fractures.


Asunto(s)
Antifibrinolíticos , Fracturas de Cadera , Traumatismos del Cuello , Fracturas de la Columna Vertebral , Ácido Tranexámico , Antifibrinolíticos/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Fijación Interna de Fracturas/métodos , Hemoglobinas , Fracturas de Cadera/cirugía , Humanos , Estudios Prospectivos , Solución Salina , Ácido Tranexámico/uso terapéutico
11.
Indian J Orthop ; 56(9): 1601-1612, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36052394

RESUMEN

Introduction: There is no distinct classification system to evaluate the bone defect in previously managed acetabular fractures. We propose a new classification system for bone defect evaluation in a previously managed acetabular fracture that will be helpful for total hip arthroplasty (THA). Materials and Methods: The preoperative pelvis radiographs of 99 THA patients with previous acetabular fractures with at least 2 years of follow-up were evaluated by 10 experienced surgeons (Paprosky and new classification systems). As per the new classification system, the five types of bone defects are circumferential, posterior wall, posterior column, both column defect, and anterior column. The interobserver and intraobserver reliability was calculated, and a consensus management plan based on the recommendation of the observers was formulated. Results: There was fair interobserver reliability for Paprosky classification (alpha coefficient 0.39) and substantial interobserver reliability for the new classification (alpha co-efficient 0.71). There was a substantial intraobserver agreement for the new classification (kappa value 0.80) and moderate intraobserver agreement for Paprosky classification (kappa value 0.55). Sixty-nine patients who were treated as per the management plan of the observers reported significant improvement in modified Harris hip score (improved from 25 to 85.88, p < 0.001). 89.7% of patients reported good to excellent outcomes. Overall best health as per EQ-5D VAS was obtained in THA following anterior column fracture (EQ-5D VAS 97.5), and relatively poor health was obtained after THA of posterior column nonunion (EQ-FD VAS 80). Conclusions:  The new classification system for bone defect evaluation in previously treated acetabular fractures is valid and reliable. The proposed surgical plan for the management of bone defects in THA provided good to excellent outcomes.

12.
Indian J Orthop ; 56(5): 918-926, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35547347

RESUMEN

Introduction: Recently, the patient-reported outcome measures (PROMs) have been considered as the most important assessment tool for surgical outcome evaluation in arthroplasty. However, no study from the Indian subcontinent has evaluated the PROM in the total hip (THA) and knee (TKA) arthroplasties. Materials and Methods: This cross-sectional study evaluated the health-related quality of life (HRQoL) of 1244 North Indian patients following primary THA and TKA who had at least one-year follow-up. This study included 617 patients with 664 THA and 627 patients with 1152 TKA. The patients were asked to answer the EQ-5D-5L questionnaires and EQ-VAS in their own languages. The EQ-5D-5L values were used to derive level frequency scores (LFS) with validated Indian norms of EuroQoL. Results: Ninety percent of THA and 82% of TKA patients rated excellent HRQoL using EQ-VAS. The regression analysis revealed age, gender, etiology and brand of prosthesis had a significant impact on EQ-5D-5L following THA. However, gender and simultaneous bilateral surgery were found to be important predictors of outcome in TKA. The mean value of LFS for THA was 0.95 ± 0.12 and TKA was 0.88 + 0.24 (p < 0.001). However, There was no difference in LFS between THA and TKA when only elderly patients (> 60 years) were considered (p = 0.168). Conclusion: THA patients reported better HRQoL than TKA in the Indian subcontinent. One of the factors for a better outcome in hip arthroplasty was the relatively younger age of the patients. Patients above 60 years of age reported similar levels of statisfactior in both THA and TKA. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-021-00589-x.

13.
Front Genet ; 13: 886487, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36212140

RESUMEN

Epigenetic modifications are inherited differences in cellular phenotypes, such as cell gene expression alterations, that occur during somatic cell divisions (also, in rare circumstances, in germ line transmission), but no alterations to the DNA sequence are involved. Histone alterations, polycomb/trithorax associated proteins, short non-coding or short RNAs, long non-coding RNAs (lncRNAs), & DNA methylation are just a few biological processes involved in epigenetic events. These various modifications are intricately linked. The transcriptional potential of genes is closely conditioned by epigenetic control, which is crucial in normal growth and development. Epigenetic mechanisms transmit genomic adaptation to an environment, resulting in a specific phenotype. The purpose of this systematic review is to glance at the roles of Estrogen signalling, polycomb/trithorax associated proteins, DNA methylation in breast cancer progression, as well as epigenetic mechanisms in breast cancer therapy, with an emphasis on functionality, regulatory factors, therapeutic value, and future challenges.

14.
Comput Intell Neurosci ; 2022: 5882144, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35909858

RESUMEN

Chronic diseases are the most severe health concern today, and heart disease is one of them. Coronary artery disease (CAD) affects blood flow to the heart, and it is the most common type of heart disease which causes a heart attack. High blood pressure, high cholesterol, and smoking significantly increase the risk of heart disease. To estimate the risk of heart disease is a complex process because it depends on various input parameters. The linear and analytical models failed due to their assumptions and limited dataset. The existing studies have used medical data for classification purposes, which help to identify the exact condition of the patient, but no one has developed any correlation equation which can be directly used to identify the patients. In this paper, mathematical models have been developed using the medical database of patients suffering from heart disease. Curve fitting and artificial neural network (ANN) have been applied to model the condition of patients to find out whether the patient is suffering from heart disease or not. The developed curve fitting model can identify the cardiac patient with accuracy, having a coefficient of determination (R 2-value) of 0.6337 and mean absolute error (MAE) of 0.293 at a root mean square error (RMSE) of 0.3688, and the ANN-based model can identify the cardiac patient with accuracy having a coefficient of determination (R 2-value) of 0.8491 and MAE of 0.20 at RMSE of 0.267, it has been found that ANN provides superior mathematical modeling than curve fitting method in identifying the heart disease patients. Medical professionals can utilize this model to identify heart patients without any angiography or computed tomography angiography test.


Asunto(s)
Cardiopatías , Aprendizaje Automático , Bases de Datos Factuales , Cardiopatías/diagnóstico , Humanos , Modelos Teóricos , Redes Neurales de la Computación
15.
Chem Commun (Camb) ; 57(14): 1693-1714, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33492315

RESUMEN

A tremendous upsurge has been seen in the recent decade for the proximal and remote functionalization of activated and unactivated substrates via palladium redox pathways. This feature article discusses some of the recent reports on direct as well as indirect C(sp3)-H functionalization via cross-coupling reactions under palladium catalysis. Activated substrates (possessing acidic C(sp3)-H) including enones, ketones, aldehydes, silylenol ethers, esters, silyl ketene acetals, amides, cyano, α-amino esters, and O-carbamates, capable of undergoing cross-coupling reactions at the α-, ß-, γ-, δ- and ε-positions, will be discussed. To overcome the challenging task of achieving regioselectivity, a variety of innovative modifications have been reported. The reports of C-H activations based on directing group, and as native functionality have been illustrated at the ß-, γ- and δ-positions. Substrates such as α-amino esters, carbonyls, carboxylic acids and their derivatives, afford site-selective C(sp3)-H functionalization via varied-sized reactive metallacycles and are a unique class of substrates whose C(sp3)-H functionalizations were earlier considered as very difficult.

16.
Anal Chem ; 82(11): 4448-56, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20446670

RESUMEN

We report the formation of core-shell diamond particles for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) made by layer-by-layer (LbL) deposition. Their synthesis begins with the amine functionalization of microdiamond by its immersion in an aqueous solution of a primary amine-containing polymer (polyallylamine (PAAm)). The amine-terminated microdiamond is then immersed in an aqueous suspension of nanodiamond, which leads to adsorption of the nanodiamond. Alternating (self-limiting) immersions in the solutions of the amine-containing polymer and the suspension of nanodiamond are continued until the desired number of nanodiamond layers is formed around the microdiamond. Finally, the core-shell particles are cross-linked with 1,2,5,6-diepoxycyclooctane or reacted with 1,2-epoxyoctadecane. Layer-by-layer deposition of PAAm and nanodiamond is also studied on planar Si/SiO(2) surfaces, which were characterized by scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS), and nuclear reaction analysis (NRA). Core-shell particles are characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), environmental scanning electron microscopy (ESEM), and Brunauer-Emmett-Teller (BET) surface area and pore size measurements. Larger (ca. 50 microm) core-shell diamond particles have much higher surface areas and analyte loading capacities in SPE than nonporous solid diamond particles. Smaller (ca. 3 microm), normal and reversed-phase, core-shell diamond particles have been used for HPLC, with 36,300 plates/m for mesitylene in a separation of benzene and alkyl benzenes and 54,800 plates/m for diazinon in a similar separation of two pesticides on a C(18) adsorbent.

17.
J Clin Orthop Trauma ; 11(6): 1072-1081, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33192011

RESUMEN

INTRODUCTION: The management of acetabulum fractures in osteoporotic elderly, as well as comminuted fractures in younger patients is likely to be difficult. These fractures need specific fixation techniques especially when the quadrilateral plate is involved. Standard implants may not be able to adequately support the fixation, so newer pre-shaped fixation plates have been proposed with some of these already in use. The concept of anatomic plates has come up for many fracture locations for providing a better buttress effect to the comminuted fragments. There has been a need to look for an anatomic buttress plates being developed for acetabulum fractures involving the quadrilateral surface. MATERIALS AND METHODS: The literature has been reviewed to find the various newer designs that have been used for buttressing the quadrilateral surface in comminuted acetabular fractures. An attempt has been made to study their design characteristics and clinical outcomes. The review also includes the analysis of Anatomic Quadrilateral plate (AQP) used in fixation of acetabulum fracture involving quadrilateral surface in a series of 33 patients. RESULTS: There has been few anatomical plates developed for the stabilization of acetabular quadrilateral surface fractures. Some of these plates have been successfully used in management of acetabular fractures primarily in young patients. Issues however remain in their application and outcomes in osteoporotic fractures of the acetabulum, as these plates support the pelvic brim fragments either from superior or medial surface. The newer development i.e. 'Anatomical Quadrilateral Plate' is optimized to counter the displacement forces due to its positioning on the pelvic brim rather than its superior or medial surface. Other special features include the possibility of longer screws across bone due to oblique position of holes, the typical location of a locking hole on the plate beam which permits dual cortical compression fixation either by using a bigger screw or a specially designed screw in screw construct across the supra-acetabular corridor. The option of using hybrid fixation of both locking and unlocked screws in AQP allows proper stress distribution on the underlying bone, aiding both primary as well as secondary stability. The minimum of one year post surgery outcome of patients having acetabular fixation using this Anatomic quadrilateral plate has been analyzed in 33 patients. Twenty three of these were aged more than 50 years and 28 out of total 33 were males. Associated injuries included Ipsilateral lower limb injury in 2 patients and distal radius fracture in 5 patients. The fracture pattern included 'Anterior column posterior hemi-transverse' in 10 patients,' Associated Both Column' injury in 9 and 'T type' acetabular fractures in 8 patients. Isolated 'Anterior column' was fractured in 6 patients. The surgical approach was 'Anterior Intra-pelvic' (AIP) in 23 patients and 'Modified Ileo-femoral' in other 10 patients. One patient had additional K L approach. Among the implants, the AQP plate was used without its pubic arm in 6 patients. The post-operative x rays showed anatomical reduction in 28 patients, while other 5 had gaps and/or steps up to 2 mm size. In subsequent car, one of these patients needed hip arthroplasty for problem arising due to collapse in fixation within six months. EQ 5D 5L telephonic score was used to know the outcome at minimum of one year follow up in 33 patients. As per this score, only 3 patients had an issue with mobility, with only one having problem in self-care activity. Six patients complained of minor limitations in carrying out their usual activities and only one patient had anxiety affecting him. In their self-assessment of overall health status, 22 patients marked it 100, 7 made it 90, 3 as 80 and 1 had marked it as 70 in a score range of 0-100. Considering the predominant elderly profile in this series of patients, the acetabular reconstruction using 'Anatomic quadrilateral plate' has shown encouraging results. CONCLUSION: For stabilization of acetabular fractures involving quadrilateral surface area and pelvic brim, various new implants have been used. The Anatomic quadrilateral plate due to its anatomical shape, the various options in fracture fixation is best optimized for management of comminuted acetabulum fractures especially in poor quality bones. It has been successful in achieving good outcome in elderly group of patients having these complex injuries.

18.
J Clin Orthop Trauma ; 11(Suppl 2): S201-S205, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32189940

RESUMEN

OBJECTIVE: Although accurate measurement of cup anteversion in hip replacement requires CT scans, however, its routine application, especially during follow-up, remains economically and ethically unreasonable. Thus, several methods have been devised for making this measurement on plain radiographs. In recent years, several ways have been adopted using software on digital radiographs. We present one such method which uses open access mathematical software GeoGebra. METHODS: Anteversion was measured on 72 radiographs (36 cemented; 36 uncemented) by three different observers using this software. One observer repeated measurements at three weeks interval. RESULTS: The intraclass correlation coefficient for interobserver variability and intraobserver variability was 0.982 (0.973-0.989) and 0.986 (0.978-0.991) respectively. There was a significant difference in the reliability of the method for cemented and uncemented cups with higher reliability for cemented cups (p < 0.001). CONCLUSION: GeoGebra software can be used as a reliable alternative for measuring acetabular cup anteversion on good quality well centred digital radiographs of the pelvis.

19.
Environ Sci Pollut Res Int ; 27(33): 41524-41539, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32686045

RESUMEN

In recent decades, various conventional techniques have been formulated around the world to evaluate the overall water quality (WQ) at particular locations. In the present study, back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS), support vector regression (SVR), and one multilinear regression (MLR) are considered for the prediction of water quality index (WQI) at three stations, namely Nizamuddin, Palla, and Udi (Chambal), across the Yamuna River, India. The nonlinear ensemble technique was proposed using the neural network ensemble (NNE) approach to improve the performance accuracy of the single models. The observed WQ parameters were provided by the Central Pollution Control Board (CPCB) including dissolved oxygen (DO), pH, biological oxygen demand (BOD), ammonia (NH3), temperature (T), and WQI. The performance of the models was evaluated by various statistical indices. The obtained results indicated the feasibility of the developed data intelligence models for predicting the WQI at the three stations with the superior modelling results of the NNE. The results also showed that the minimum values for root mean square (RMS) varied between 0.1213 and 0.4107, 0.003 and 0.0367, and 0.002 and 0.0272 for Nizamuddin, Palla, and Udi (Chambal), respectively. ANFIS-M3, BPNN-M4, and BPNN-M3 improved the performance with regard to an absolute error by 41%, 4%, and 3%, over other models for Nizamuddin, Palla, and Udi (Chambal) stations, respectively. The predictive comparison demonstrated that NNE proved to be effective and can therefore serve as a reliable prediction approach. The inferences of this paper would be of interest to policymakers in terms of WQ for establishing sustainable management strategies of water resources.


Asunto(s)
Lógica Difusa , Calidad del Agua , India , Inteligencia , Aprendizaje Automático , Ríos
20.
Lab Chip ; 9(12): 1789-96, 2009 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-19495464

RESUMEN

The selective adsorption of reagents is often essential for bioarray and lab-on-a-chip type devices. As the starting point for a bioarray, alkyl monolayer terminated silicon shards were photopatterned in a few nanoseconds with thousands of wells (spots) using an optical element, a microlens array. Polyallylamine (PAAm), a primary amine containing polymer, adsorbed with little selectivity to the spots, i.e., silicon oxide, over the hydrophobic background. However, at appropriate concentrations, addition of a cationic surfactant to the PAAm deposition solution, cetyltrimethylammonium chloride, prevented the nonspecific adsorption of PAAm onto the hydrophobic monolayer, while directing it effectively to the active spots on the device. A nonionic surfactant was less effective in preventing the nonspecific adsorption of PAAm onto the hydrophobic monolayer. The localized reactions/interactions of adsorbed PAAm with four species that are useful for bioconjugate chemistry: glutaric anhydride, phenylenediisothiocyanate, biotin NHS ester, and an oligonucleotide (DNA) were shown in the spots of an array. The reactivity of PAAm was further demonstrated with an isocyanate. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) played an important role in confirming selective surface reactivity and adsorption. X-ray photoelectron spectroscopy (XPS), spectroscopic ellipsometry, and wetting confirmed PAAm reactivity on planar substrates.


Asunto(s)
Análisis por Micromatrices/métodos , Microtecnología/métodos , Poliaminas/química , Silicio/química , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Análisis por Micromatrices/instrumentación , Dióxido de Silicio/química , Análisis Espectral , Propiedades de Superficie
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