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1.
Sci Rep ; 13(1): 14821, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684241

RESUMEN

The inverter is considered the core of the PV power plant. The inverter's failure leads to generation loss and decreases plant availability. So, it is required to investigate a clear Root Cause Analysis (RCA) to deduce the failure causes and implement the required corrective action in addition to the preventive action to avoid more inverter failure, hereby maintaining the plant available to a certain value. This paper discusses real-time mode operation data analysis of the PV grid-connected inverter due to real central inverter incidents in Benban solar park located in Egypt.The central inverter plays an important role in the Mega-Scale PV power plant. The main function of this inverter is to convert the DC power produced by the PV modules to AC power to be injected into the utility grid by considering specific characteristics based on the grid code. The availability of any PV power plant directly depends on the healthy inverter's operation. The more increases for the installed inverters, the less availability loss in the case of inverter partial or catastrophic failures. So, it is required to focus on the failure causes of the central inverter by implementing a technical analysis using the available operational data. The monitored data of the central inverter in the PV power plant is classified into two types. The first type is the continuous time data stored in the memory. It represents the waveforms of inverter outputs like voltage, current, frequency, …. etc. Unfortunately, in case of a catastrophic failure, the central inverter is completely charred, and the continuous time data is lost due to storage memory damage. The second type is the operation data that is recorded by the SCADA system (per one-minute interval). Hereby, the operation data is the sole data in the case of the completely charred inverter. The representation of the operational data in curves indicates symptoms that can be used for the RCA processes. The investigation outcomes include three results. The first result is detecting the signature of the IGBT thermal stress on the voltage balance of the DC link capacitor. The second result is verifying a scenario for the cause of the IGBT failure by implementing a technical mathematical model based on the detected symptoms that denote the fault signature which is considered the thread-tip for detecting the failure cause. The third result is the simulating scenario for the interpretation of a DC link capacitors explosion due to the short circuit fault that occurred due to IGBT failure. The investigation in this paper is performed based on operation data analysis of the PV grid-connected inverter (central type) due to a real incident. The analysis methodology is based on mathematical calculation for the IGBT junction temperature using the measured heatsink temperature. The study concludes that after the IGBT failure occurred, it was a short circuit for a while and closed the terminals of the DC link capacitors. So, the DC link capacitors exploded and produced heavy sparks that led to enough fire to burn the inverter container completely.

2.
Int J Biol Macromol ; 249: 126011, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37517763

RESUMEN

In the last decades, bio-based active food packaging materials have received much attention. It is known that the utilization of traditional materials for food packaging applications lack some critical characteristics such as resistance to the harmful microbes that cause a damage to the preserved foods. Therefore, the current study aimed to find an alternative packaging films comprises an efficient biopolymers. This research work was designed to prepare film mats using hydroxypropyl starch (HPS), polyvinyl alcohol (PVA), palmitic acid (PA) and biosynthesized zinc oxide nanoparticles (ZnONPs). The fabricated films were coded as 1H, 2H, 3H and 4H based on the utilized concentration of ZnONPs. The biosynthesized ZnONPs and the bio-based films loaded with ZnONPs were characterized. The results revealed that ZnONPs exhibited nearly spherical shape and size ∼40 nm. The surface structure of the produced bioactive packaging films exhibited smooth with homogeneous features, excellent mechanical and thermal stability properties. The prepared bioactive packaging film loaded with ZnONPs (4H) exhibited superior antibacterial activity among other films against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 with inhibition zones 15.1 ± 0.76 and 12.1 ± 0.71 mm respectively. Correspondingly, packing film 4H exhibited potential antifungal activity toward Aspergillus niger RCMB 02724, A. flavus RCMB 02782, Penicillium expansum IMI 89372 and Fusarium oxysporum RCMB 001004 with inhibition zones (16 ± 1.0, 22 ± 0.90, 18.0 ± 1.1 and12.3 ± 0.57 mm respectively). Moreover, all prepared films did not show cytotoxicity on the normal cell line (Wi38) and recorded biodegradability properties that reached around 85 % after four weeks in soil. Based on these results, the antimicrobial films comprising HPS/PVA and loaded with the biosynthesized ZnONPs can be considered as a suitable film for food packaging purposes.


Asunto(s)
Antiinfecciosos , Nanopartículas , Óxido de Zinc , Alcohol Polivinílico/química , Embalaje de Alimentos/métodos , Óxido de Zinc/química , Almidón/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/química , Nanopartículas/química
3.
Heliyon ; 9(4): e14695, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37025775

RESUMEN

Fluorescence is well-known nowadays as one of the most efficient anti-counterfeiting techniques. Zinc oxide quantum dots (ZnOQds) are exceptionally fluorescence when exposed to ultraviolet (UV) light, which makes them a candidate for anti-counterfeiting printing. The resulting anti-counterfeiting papers are sustainable and resistance against organic dyes. In this work, ZnOQds were prepared via a green method and characterized under UV-visible spectroscopy, along with microscopic observations by transmission electron microscopy (TEM) and crystallography by X-ray diffraction (XRD). Formation of ZnOQds nanocrystals with an average partials size of 7.3 nm was approved. Additionally, double-layers sheets were prepared at two loading concentrations of ZnOQds, namely 0.5 and 1 (wt./v) and underwent characterization using a topographical surface study via field emission scanning electron microscopy (FE-SEM). Hybrid sheets were mechanically more stable compared to single-layer paper and likewise polymer film. Moreover, aging simulation approved a high stability for hybrid sheets. Particularly, the photoluminescence emission affirmed anti-aging character of hybrid paper for more than 25 years. The hybrid sheets also showed a broad range of antimicrobial activity.

4.
Poult Sci ; 102(4): 102544, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36867921

RESUMEN

This study evaluated effects of feeding low-bush wild blueberry (LBP) and organic American cranberry (CRP) pomaces without or with multienzyme supplement (ENZ) on growth performance, organ weight and plasma metabolites in broiler chickens. Nonenzyme-fed (no-ENZ: n = 1,575) and enzyme-fed (ENZ: n = 1,575) day-old male Cobb500 broilers were placed in floor pens (45 chicks/pen) and allocated to five corn-soybean meal-based diets: a basal diet supplemented with either bacitracin methylene disalicylate (BMD, 55 mg/kg), 0.5 or 1% of CRP or LBP in a 2 × 5 factorial design for 35-day experiment. Body weight (BW), feed intake (FI) and mortality were recorded whereas BW gain (BWG) and feed conversion ratio (FCR) were calculated. Birds were sampled at days 21 and 35 for organ weights and plasma metabolites. There were no interactions between diet and ENZ on any parameter (P > 0.05) and no effect of ENZ on overall (d 0-35) growth performance and organ weights (P > 0.05). Birds fed BMD were heavier (P < 0.05) at d 35 and had better overall FCR than berry-supplemented birds. Birds fed 1% LBP had poor FCR than birds fed 0.5% CRP. Birds fed LBP exhibited heavier liver (P < 0.05) than birds fed BMD or 1% CRP. The highest plasma concentrations of aspartate transaminase (AST), creatine kinase (CK) at d 28 and gamma-glutamyl transferase (GGT) at d 35 were found in ENZ-fed birds (P < 0.05). At d 28, birds fed 0.5% LBP showed higher plasma AST and CK concentrations (P < 0.05). However, CRP feeding resulted in a lower plasma CK level compared with BMD feeding (P < 0.05). The lowest cholesterol level was detected in 1% CRP-fed birds. In conclusion, this study showed no ENZ effects to potentiate berry pomaces on the overall growth performance of broilers (P < 0.05. However, plasma profiles revealed the potential of ENZ to modulate the metabolism of pomace-fed broilers. LBP increased BW during the starter phase, while CRP increased BW during the grower phase.


Asunto(s)
Pollos , Zea mays , Animales , Masculino , Frutas , Tamaño de los Órganos , Glycine max , Harina , Suplementos Dietéticos/análisis , Dieta/veterinaria , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales
5.
Sci Rep ; 12(1): 19197, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357465

RESUMEN

This study deals with the production of natural fiber plastic composites (NFPCs) to reduce environmental pollution with agricultural and plastic waste. Where the NFPCs were prepared from waste/pure polyethylene (WPE) (pure polyethylene (50%)/recycled polyethylene (50%)) and modified sunflower waste via an eco-friendly and economic biological process. The sunflower fibers (SF) were treated via whole selective fungal isolate, namely, Rhizopus oryzae (acc no. OM912662) using two different incubation conditions; submerged (Sub), and solid-state fermentation (SSF) to enhance the fibers' compatibility with WPE. The treated and untreated fibers were added to WPE with various concentrations (10 and 20 wt%). The morphology and structure of fibers were characterised by a scanning electron microscope (SEM) and attenuated total reflection-Fourier transform infrared (ATR-FTIR). Furthermore, the mechanical properties, morphology, biodegradation and water vapour transmission rate (WVTR) for the prepared NFPCs were investigated. The results showed that compatibility, mechanical properties and biodegradation of NFPCs were improved by the addition of sunflower fibers treated by SSF conditions.


Asunto(s)
Plásticos , Madera , Reciclaje/métodos , Agricultura , Polietileno
6.
Ultrasound Med Biol ; 48(8): 1397-1409, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35667977

RESUMEN

Because of the insidious character and variations in presenting symptoms, Charcot-Marie-Tooth (CMT) disease is challenging to diagnose in children. Diagnosis is based on clinical and nerve conduction studies, as well as genetic examination. Therefore, competent nerve imaging techniques and non-invasive alternatives to nerve conduction studies are a necessity, especially in children. We performed a systematic review and meta-analysis to evaluate the current evidence and effectiveness of ultrasound in investigating nerve cross-sectional area (CSA) in those with CMT compared with healthy controls and to pool the CSA measurements. We included studies published in international peer-reviewed journals that measured nerve CSA by ultrasound in patients with CMT. We implemented double-arm meta-analyses to compare the mean CSA of nerves between patients with CMT and healthy controls by calculating the pooled mean difference in CSA. Moreover, we performed subgroup analyses by stratifying the studies according to the site of CSA measurement and examined the difference in nerve CSA between CMT1A and other CMT types. The included studies provide measurements of 12 nerve roots and nerves (vagus, C3, C4, C5, C6, greater auricular, phrenic, median, ulnar, fibular, tibial and sural nerves) in 628 patients with CMT and 586 healthy controls with a total of 6061 measured nerves. Meta-analyses of sonographic nerve CSA are provided to express nerve ultrasonography in the diagnosis of CMT patient.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Enfermedad de Charcot-Marie-Tooth/diagnóstico por imagen , Enfermedad de Charcot-Marie-Tooth/genética , Niño , Humanos , Nervios Periféricos/diagnóstico por imagen , Nervio Sural , Ultrasonografía/métodos
7.
Pediatr Dermatol ; 39(2): 182-186, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35178737

RESUMEN

INTRODUCTION: Community health workers (CHWs), or promotora de salud, have an important role in healthcare education and advocacy in the Latin American community. We aimed to determine the impact of a promotora de salud program on attitudes and beliefs regarding AD management among Latin American caregivers of pediatric patients with atopic dermatitis. METHODS: This is a sub-study of an ongoing randomized, investigator-blinded, placebo-controlled trial. Mann-Whitney U tests compared questionnaire responses in the standard education group to the promotora group. RESULTS: Caregivers in the promotora group were more likely to state that they knew how to apply wet wraps and use bleach (sodium hypochlorite) baths at 1 month (wet wraps p = .027, bleach baths p = .005) and 3 months (wet wraps p = .005, bleach baths p < .001) demonstrating greater self-efficacy, defined as an individual's belief in their capacity to execute a certain behavior to achieve a desired outcome, compared with the standard education group. CONCLUSIONS: Culturally competent and language concordant educational interventions may improve confidence in utilizing wet wraps and bleach baths among Latin-American caregivers of children with atopic dermatitis, which may improve AD outcomes in the Latin-American community.


Asunto(s)
Dermatitis Atópica , Actitud , Cuidadores , Niño , Agentes Comunitarios de Salud , Dermatitis Atópica/terapia , Humanos , Lenguaje
8.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-977519

RESUMEN

Aims@#Potatoes are considered one of the most strategic vegetable crops all over the world. Alternaria alternata has recently contaminated certain potatoes farms in different regions in Egypt. Among thirteen samples from fifteen regions were studied in a precedent study. Our study was aimed to investigate the effect of Bacillus thuringiensis subsp. Kurosaki suspension on inhibiting the growth of the three tested isolates of A. alternata and minimizing their mycotoxins production in vitro using three isolates with three levels of highly, moderate and low pathogenicity with unequal amounts of dual mycotoxins production.@*Methodology and results@#Three isolates of A. alternata from three regions, Kom Hamada (KH3), Alamin (Alam1) and Nobaria (NO3), which were determined as a producer of tenuazonic acid (TeA) and alternariol monomethyl ether (AME) toxins. Bacillus thuringiensis (Bt) use as commercial fungicide was applied with three suspension concentrations (75, 150 and 300 μg/mL) as inhibitor for the two mycotoxins. Our results illustrated that the three tested isolates recorded high TeA and AME inhibition efficacies by increasing the Bt suspension concentration. The highest inhibitory concentration of Bt was at concentration 75 μg/mL for isolated from Nobaria third region (NO3) and Alam1 it was (99.83 and 99.74%) for mycotoxin (AME) while, TeA mycotoxin had the most inhibition percentage (99.58%) at concentration 150 μg/mL for the isolate (NO3).@*Conclusion, significance and impact of study@#The preliminary results of the study suggest that B. thuringiensis spores’ suspension with different concentrations can be used as anti-mycotoxigenic agents to inhibit the (TeA) and (AME) mycotoxins produced by Alternaria alternata.


Asunto(s)
Bacillus thuringiensis , Solanum tuberosum
9.
Regen Med ; 16(11): 975-988, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34596433

RESUMEN

Background: Cell therapy is a promising method for improving healing in chronic ulcers through delivery of isolated adipose-derived stromal vascular fraction. Objectives: This study investigates the autologous stem cell yield of adipose tissue and its efficacy in chronic ulcers compared with conventional methods. Methods: This study was a randomized controlled trial. After the study design and protocol were established and ethical committee approval was obtained, we enrolled 100 patients divided into study and control groups. In the study group, we performed debridement and autologous stem cell injection every 3 weeks. The control group was treated with debridement and conventional dressing. Assessments included clinical and histological parameters. Results: The study group showed improved healing. Conclusion: Using autologous adipose-derived stromal vascular fraction cells is an effective treatment method for chronic ulcers. This study was registered on the Pan-African Clinical Trial Registry and the number of the registry was PACTR201709002519185.


Asunto(s)
Úlcera , Cicatrización de Heridas , Tejido Adiposo , Vendajes , Humanos , Células del Estroma , Resultado del Tratamiento
10.
Int J Pharm ; 607: 121010, 2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34391852

RESUMEN

Cytomegalovirus (CMV) retinitisis a vision-threatening disease that principally afflicts immunosuppressed patients. For the management of the disease, Ganciclovir (GCV) is usually administered systemically, where patients may suffer severe untoward effects. The ocularly-applied alternatives are either the intravitreal injections, which are frequently administered due to GCV short half-life, or the sustained-release implants, which require surgical removal upon drug depletion. Both therapies are invasive and should be completed by a medical expert. The objective of this research was to formulate a non-invasive alternative represented in GCV loaded ultra-fluidic glycerosomes (UFGs), which are glycerosomes containing sodium taurocholate as an edge activator (EA), then incorporating the optimal UFGs in polylactic acid (PLA)-based 3D printed ocusert to prolong the release of GCV. The experimental design, the statistical analysis, and the optimization were performed via Design-Expert® software. The optimal formulation (UFGs 6; composed of 600 mg Phosphatidylcholine (PC), 20 mg cholesterol, 0.1:1 weight molar ratio of EA: PC and 1 gm glycerol) possessed nanovesicles (441.70 ± 1.13 nm) that entrapped 69.33 ± 0.28 % of GCV, with zeta potential value of -37.00 ± 0.42 mV and deformability index value of 74.68 ± 0.71. The confocal microscopy results showed the supreme penetration power of UFGs through the rabbit's cornea, compared to edge-activated vesicles and conventional glycerosomes from the laden ocusert. Moreover, the topical application of the ocusert laden with the optimal GCV loaded UFGs to the rabbits' eyes evidenced their safety as per the histopathological findings. Furthermore, a pharmacokinetic study in the rabbit's aqueous humor demonstrated the sustained release of GCV from the ocusert laden with the optimal GCV loaded UFGs over 5 days. Inclusively, the ocusert laden with UFGs could be considered as a non-invasive sustaining drug delivery system of GCV for the management of CMV retinitis.


Asunto(s)
Retinitis por Citomegalovirus , Ganciclovir , Animales , Antivirales , Retinitis por Citomegalovirus/tratamiento farmacológico , Humanos , Pilocarpina , Impresión Tridimensional , Conejos
11.
J Dermatolog Treat ; 32(2): 242-249, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31180258

RESUMEN

OBJECTIVES: To explore the impact of using topical stem cell-conditioned medium (SC-CM) after fractional carbon dioxide laser (FCL) vs. combined FCL and platelet-rich plasma (PRP) or FCL alone in treatment of atrophic acne scars. METHODS: Thirty-three patients were randomly divided into two split-face groups. Group I (n = 17) received FCL plus topical SC-CM on one side or FCL plus saline on the other. Group II (n = 16) received FCL plus topical PRP or SC-CM. All patients had three monthly sessions. Clinical assessment was done at each visit, with a final assessment after 3 months. Skin biopsies were obtained for histological and quantitative molecular analysis after treatment. RESULTS: No significant difference in clinical improvement of acne scars was observed between the FCL/SC-CM and FCL only sides (p = .63), while better and faster improvement was detected on FCL/PRP side compared to FCL/SC-CM side (p = .006). There was no significant difference in downtime or adverse effects between the treated sides in either group. Dermal collagen was increased and procollagen type I gene was upregulated in both FCL/PRP and FCL/SC-CM sides compared to FCL only sides (p = .001 and p = .041, respectively). CONCLUSIONS: Topical SC-CM could potentially enhance the efficacy of FCL. However, PRP seems to be a better alternative.


Asunto(s)
Acné Vulgar/patología , Cicatriz/terapia , Medios de Cultivo Condicionados/química , Láseres de Gas/uso terapéutico , Plasma Rico en Plaquetas/química , Acné Vulgar/complicaciones , Adyuvantes Inmunológicos , Adulto , Cicatriz/etiología , Femenino , Humanos , Terapia por Luz de Baja Intensidad , Masculino , Satisfacción del Paciente , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Células Madre/citología , Células Madre/metabolismo , Resultado del Tratamiento , Adulto Joven
12.
Expert Opin Drug Saf ; 20(4): 467-474, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33337920

RESUMEN

Background: Erenumab has recently been approved as a pharmacological treatment for the prevention of migraine. However, the incidence estimates of adverse drug reactions (ADRs) were not consistent among studies. Consequently, pooled measures of the incidences of ADRs that accounts for inter-study heterogeneity are desirable. In addition, little is known on the factors leading to such heterogeneity.Research design and methods: Clinical trials evaluating the occurrence of ADRs related to erenumab in migraine patients were searched with Ovid MEDLINE until April 2020. Random intercept models were used to estimate the pooled incidence of the ADRs reported at least in 5 different study populations. To examine whether specific factors correlated with the pooled incidence, we performed random-effects meta-regression.Results: Of 138 retrieved references, 8 clinical trials were included in the meta-analysis. We observed a significant heterogeneity of the incidence estimates of back pain, influenza, nasopharyngitis, and upper respiratory tract infection (URTI). Most of the observed heterogeneity is ascribed to treatment duration for back pain (p = 0.045), influenza (p < 0.001) and URTI (p < 0.001), and significantly attributed to Body Mass Index (BMI) for nasopharyngitis (p < 0.001).Conclusions: Back pain, influenza, nasopharyngitis and URTI showed a significant heterogeneity of incidence estimates.


Asunto(s)
Anticuerpos Monoclonales Humanizados/efectos adversos , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/efectos adversos , Trastornos Migrañosos/prevención & control , Anticuerpos Monoclonales Humanizados/administración & dosificación , Índice de Masa Corporal , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina/administración & dosificación , Humanos , Análisis de Regresión
13.
Science ; 368(6493): 889-892, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32439794

RESUMEN

Optical atomic clocks are poised to redefine the Système International (SI) second, thanks to stability and accuracy more than 100 times better than the current microwave atomic clock standard. However, the best optical clocks have not seen their performance transferred to the electronic domain, where radar, navigation, communications, and fundamental research rely on less stable microwave sources. By comparing two independent optical-to-electronic signal generators, we demonstrate a 10-gigahertz microwave signal with phase that exactly tracks that of the optical clock phase from which it is derived, yielding an absolute fractional frequency instability of 1 × 10-18 in the electronic domain. Such faithful reproduction of the optical clock phase expands the opportunities for optical clocks both technologically and scientifically for time dissemination, navigation, and long-baseline interferometric imaging.

14.
Gland Surg ; 8(5): 527-536, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31741883

RESUMEN

BACKGROUND: Breast conserving surgery (BCS) followed by radiotherapy has gained great popularity in the treatment of breast cancer over the past years. However, radiation therapy can lead to many unfavourable aesthetic outcomes including significant volume/skin deficiency, nipple areola complex distortion and skin contraction. We present our experience in using pedicled perforator flaps to tackle the resultant partial breast defects or deformities. METHODS: A retrospective data analysis study on Thirty patients with post breast conserving surgery (BCS) partial breast defects who were managed with pedicled per-forator flaps including muscle sparing latissimus dorsi muscle flap (MSLD), thoraco-dorsal artery perforator flap (TDAP) and intercostal artery perforator flap (ICAP) in the period between December 2008 and December 2018. RESULTS: Defects were in all quadrants apart from the upper inner quadrant. The reconstructive techniques included TDAP flap 6/30 (20%), MSLD flap 20/30 (66.7%), AICAP flap 4/30 (13.3%). Age ranges 22-35 (mean 29). All flaps showed complete survival, one nipple areola complex superficial epidermolysis was experienced, and one patient presented with fat necrosis. No resultant donor site morbidity apart from scar revision for excess skin at the axillary fold in one patient. The overall satisfaction reached 94% with only 8 patients who required lipofilling to maximize the cosmetic outcome. CONCLUSIONS: The availability of a range of reliable techniques including thoracodorsal/intercostal artery perforator flap (TAP/ICAP) and muscle sparing lattissimus dorsi flap (MSLD) allow optimum results to be achieved in the treatment of partial breast defects following breast conserving surgery.

15.
Case Rep Orthop ; 2018: 7532358, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30034899

RESUMEN

BACKGROUND: Pigmented villonodular synovitis is a rare pathology causing hyperplasia of the synovium. It mostly affects young populations and most commonly the knee joint. It rarely affects the posterior compartment of the knee as the case presented in this study. Open surgery is usually used to treat this condition; however, in our case it was excised arthroscopically despite the anatomical challenges of the posterior knee compartment. CASE PRESENTATION: This case presents a female patient with a complaint of posterior-region pain of her left knee post direct trauma post fall. This was directly followed by knee joint blockage for 1-week duration before presentation to the hospital. On MRI, she was found to have a multiloculated hemosiderin-containing structure of synovial origin within the femoral notch, extending beyond the joint capsule displacing the popliteal vessels. The patient underwent arthroscopic resection of the lesion, which was found to be pigmented villonodular synovitis on anatomopathological examination. On 6-month follow-up, the patient showed good clinical evolution with the absence of symptoms and back-to-normal daily activities. CONCLUSION: This is a rare case of PVNS affecting the posterior knee joint compartment of a middle-aged woman, which was successfully excised arthroscopically, with no residual affected tissue or recurrence on 6-month follow-up.

16.
Case Rep Orthop ; 2018: 5401634, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29666736

RESUMEN

Medial epicondyle entrapment after an acute fracture dislocation of the elbow is a common finding in the pediatric population, but a rare finding in adults. We present a case of an adult patient diagnosed with a traumatic fracture dislocation of the elbow joint with intra-articular entrapment of the medial epicondyle. After initial evaluation, closed reduction was done. Stability testing after reduction showed an unstable joint; thus, open reduction and internal fixation was decided.

17.
ACS Omega ; 3(3): 2757-2764, 2018 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-31458552

RESUMEN

A range of microporous, imide-based polymers were newly synthesized using two-step poly-condensation reactions of bis(carboxylic anhydride) and various aromatic diamines for CO2 gas capture and storage applications. In this report, we attempted to assess the relative significance of molecular structural aspects through the manipulation of the conformational characteristics of the building blocks of the polymeric structures, the spiro-containing acid anhydride and the aromatic amines, to induce greater intrinsic microporosity and higher surface areas for the resulting solids. Results obtained from this study were thus used to outline a working relationship between the structural diversity of the constructed porous solids and their performance as CO2 sorbents.

18.
Beilstein J Org Chem ; 13: 558-563, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28405235

RESUMEN

Conjugated microporous polymers (CMPs) are materials of low density and high intrinsic porosity. This is due to the use of rigid building blocks consisting only of lightweight elements. These materials are usually stable up to temperatures of 400 °C and are chemically inert, since the networks are highly crosslinked via strong covalent bonds, making them ideal candidates for demanding applications in hostile environments. However, the high stability and chemical inertness pose problems in the processing of the CMP materials and their integration in functional devices. Especially the application of these materials for membrane separation has been limited due to their insoluble nature when synthesized as bulk material. To make full use of the beneficial properties of CMPs for membrane applications, their synthesis and functionalization on surfaces become increasingly important. In this respect, we recently introduced the solid liquid interfacial layer-by-layer (LbL) synthesis of CMP-nanomembranes via Cu catalyzed azide-alkyne cycloaddition (CuAAC). However, this process featured very long reaction times and limited scalability. Herein we present the synthesis of surface grown CMP thin films and nanomembranes via light induced thiol-yne click reaction. Using this reaction, we could greatly enhance the CMP nanomembrane synthesis and further broaden the variability of the LbL approach.

19.
Chem Commun (Camb) ; 52(81): 12032-12035, 2016 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-27711365

RESUMEN

A one-pot, bottom-up assembly of a pyrimidine-containing porous-organic polymer (PyPOP) was conducted to homogenously deposit the PyPOP atop unmodified graphene sheets, affording a composite material PyPOP@G. The PyPOP demonstrated an appreciable affinity toward CO2 capture but was found to be largely insulating, hindering its usage in potential electrochemical conversion of CO2. However, its composite with graphene was found to be microporous, with maintained affinity toward CO2 and furthermore demonstrated significant electrochemical activity toward CO2 reduction (5 mA cm-2 at -1.6 V), not observed in either of its two components separately.

20.
ACS Appl Mater Interfaces ; 8(31): 19994-20002, 2016 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-27428561

RESUMEN

A number of permanently porous polymers containing Ru(bpy)n photosensitizer or a cobaloxime complex, as a proton-reduction catalyst, were constructed via one-pot Sonogashira-Hagihara (SH) cross-coupling reactions. This process required minimal workup to access porous platforms with control over the apparent surface area, pore volume, and chemical functionality from suitable molecular building blocks (MBBs) containing the Ru or Co complexes, as rigid and multitopic nodes. The cobaloxime molecular building block, generated through in situ metalation, afforded a microporous solid that demonstrated noticeable catalytic activity toward hydrogen-evolution reaction (HER) with remarkable recyclability. We further demonstrated, in two cases, the ability to affect the excited-state lifetime of the covalently immobilized Ru(bpy)3 complex attained through deliberate utilization of the organic linkers of variable dimensions. Overall, this approach facilitates construction of tunable porous solids, with hybrid composition and pronounced chemical and physical stability, based on the well-known Ru(bpy)nor the cobaloxime complexes.

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