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1.
Crit Rev Biotechnol ; 39(6): 835-859, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31185749

RESUMEN

Microalgae have been exploited for biofuel generation in the current era due to its enormous energy content, fast cellular growth rate, inexpensive culture approaches, accumulation of inorganic compounds, and CO2 sequestration. Currently, research is ongoing towards the advancement of the microalgae cultivation parameters to enhance the biomass yield. The main objective of this study was to delineate the progress of physicochemical parameters for microalgae cultivation such as gaseous transfer, mixing, light demand, temperature, pH, nutrients and the culture period. This review demonstrates the latest research trends on mass transfer coefficient of different microalgae culturing reactors, gas velocity optimization, light intensity, retention time, and radiance effects on microalgae cellular growth, temperature impact on chlorophyll production, and nutrient dosage ratios for cellulosic metabolism to avoid nutrient deprivation. Besides that, cultivation approaches for microalgae associated with mathematical modeling for different parameters, mechanisms of microalgal growth rate and doubling time have been elaborately described. Along with that, this review also documents potential lipid-carbohydrate-protein enriched microalgae candidates for biofuel, biomass productivity, and different cultivation conditions including open-pond cultivation, closed-loop cultivation, and photobioreactors. Various photobioreactor types, the microalgae strain, productivity, advantages, and limitations were tabulated. In line with microalgae cultivation, this study also outlines in detail numerous biofuels from microalgae.


Asunto(s)
Biocombustibles , Biotecnología , Microalgas , Biomasa , Fenómenos Químicos , Fotobiorreactores
2.
FASEB J ; 29(2): 684-95, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25392266

RESUMEN

Ingestion of a commensal bacteria, Lactobacillus rhamnosus JB-1, has potent immunoregulatory effects, and changes nerve-dependent colon migrating motor complexes (MMCs), enteric nerve function, and behavior. How these alterations occur is unknown. JB-1 microvesicles (MVs) are enriched for heat shock protein components such as chaperonin 60 heat-shock protein isolated from Escherichia coli (GroEL) and reproduce regulatory and neuronal effects in vitro and in vivo. Ingested labeled MVs were detected in murine Peyer's patch (PP) dendritic cells (DCs) within 18 h. After 3 d, PP and mesenteric lymph node DCs assumed a regulatory phenotype and increased functional regulatory CD4(+)25(+)Foxp3+ T cells. JB-1, MVs, and GroEL similarly induced phenotypic change in cocultured DCs via multiple pathways including C-type lectin receptors specific intercellular adhesion molecule-3 grabbing non-integrin-related 1 and Dectin-1, as well as TLR-2 and -9. JB-1 and MVs also decreased the amplitude of neuronally dependent MMCs in an ex vivo model of peristalsis. Gut epithelial, but not direct neuronal application of, MVs, replicated functional effects of JB-1 on in situ patch-clamped enteric neurons. GroEL and anti-TLR-2 were without effect in this system, suggesting the importance of epithelium neuron signaling and discrimination between pathways for bacteria-neuron and -immune communication. Together these results offer a mechanistic explanation of how Gram-positive commensals and probiotics may influence the host's immune and nervous systems.


Asunto(s)
Sistema Nervioso Entérico/fisiología , Tracto Gastrointestinal/inervación , Sistema Inmunológico/fisiología , Lacticaseibacillus rhamnosus/inmunología , Animales , Células de la Médula Ósea/citología , Linfocitos T CD4-Positivos/citología , Chaperonina 60/metabolismo , Técnicas de Cocultivo , Células Dendríticas/citología , Células Dendríticas/microbiología , Factores de Transcripción Forkhead/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/metabolismo , Ganglios Linfáticos/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Neuronas/metabolismo , Peristaltismo , Ganglios Linfáticos Agregados/microbiología , Fenotipo , Probióticos , Proteómica , Transducción de Señal
3.
Ann Gen Psychiatry ; 13(1): 31, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25422670

RESUMEN

BACKGROUND: Despite substantial research on the comorbidity of anxiety disorders including posttraumatic stress disorder (PTSD) and chronic pain, little is known about the mechanisms underlying these conditions that might be potentially similar. Evoked pain sensitivity is one factor that has been associated with several pain conditions which might also have relevance to anxiety disorders and PTSD. The aim of this preliminary study was to examine evoked pain sensitivity in PTSD compared to other anxiety disorders and in control participants. METHOD: The study used a cross-sectional case-control design in which participants completed a battery of questionnaires and structured interview and underwent cold pressor testing. RESULTS: Of 61 total participants, those in the PTSD (n =16) and other anxiety groups (n =12) endorsed significantly higher levels of psychological symptoms and poorer health functioning than control participants (n =33). The linear trend across baseline, threshold, and tolerance pain ratings from the cold pressor task significantly differed between participants with PTSD and the other anxiety and control groups suggesting lower pain sensitivity to a standardized stimulus of pain in individuals with PTSD. CONCLUSIONS: These findings are similar to some of the prior research and suggest that individuals with PTSD may exhibit lower cold pain sensitivity compared to those with other anxiety disorders. There is a need for future research to determine explanatory mechanisms.

4.
Cureus ; 16(5): e60101, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38860087

RESUMEN

Meige syndrome (MS) is a cranial dystonia that involves blepharospasm and oromandibular dystonia. It can also evolve to include other adjacent muscle groups in the cervical region. It typically presents in middle-aged females, and while the disorder is relatively uncommon, its exact prevalence varies. Diagnosis is typically made with a thorough history and physical and workup to rule out other causes. Treatment options include medical management with gamma-aminobutyric acid (GABA) antagonists, dopamine antagonists, and anticholinergics for short-term management. Long-term treatment options are Botox and deep brain stimulation. This case report presents a 56-year-old female with a complex presentation of MS; the patient's symptoms progressed from isolated blepharospasms to involve orofacial and cervical musculature. A distinctive aspect of this case was the simultaneous presence of upper motor neuron (UMN) signs in the patient alongside acute to subacute compression fractures of the superior endplate of C7 and T3, as revealed by cervical spine imaging. Treatment with clonazepam led to significant symptomatic improvement, highlighting the importance of a multimodal approach in managing MS. This case underscores the need for careful clinical evaluation, collaboration with movement disorder specialists, and ongoing research efforts to enhance understanding and treatment of MS.

5.
J Geriatr Oncol ; 14(8): 101601, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37597295

RESUMEN

INTRODUCTION: Differences in symptom distress among older (age 65-74) and very old (age 75+) patients with cancer, compared to younger patients, remain to be well explored. These differences are important to understand given the heterogeneity of older populations and may have implications for age-appropriate symptom detection and management. MATERIALS AND METHODS: We examined routinely collected Edmonton Symptom Assessment System Revised (ESAS-r) scores from 9,143 patients age 40+ initiating chemotherapy for solid malignancies at a single academic cancer centre, between September 2011 and May 2019. We used multivariable logistic regression models to determine associations between the most common symptoms and age group (ages 40-64, 65-74, 75-84, and 85+), cancer site, clinical stage, sex, and income levels. We focused our findings on patients with the five most common cancers, breast (n = 1,532), prostate (n = 923), lung (n = 889), pancreatic (n = 429), and colorectal (n = 368), prior to receiving treatment. RESULTS: Within our sample, 58.0% were age 40-64, 27.3% age 65-74, 11.8% age 75-84, and 2.9% age 85+. Among the nine symptoms in the ESAS-r (anxiety, depression, tiredness, wellbeing, nausea, pain, drowsiness, appetite, and shortness of breath), the most common symptoms overall were anxiety (moderate-severe scores [ESAS-r 4 or higher] were reported by 33.8% of patients), lack of well-being (38.3%), and tiredness (38.3%). Older age was associated with lower odds of moderate/severe anxiety (odds ratio [OR] 0.81, 95% confidence interval [CI] 0.73-0.90 for age 65-74; OR 0.81, 95%CI 0.70-0.93 for age 75-84; OR 0.62, 95%CI 0.47-0.82 for age 85+; referent is 40-64-year-olds for all analyses), and increased odds of tiredness (OR 1.00, 95%CI 0.90-1.11 for age 65-74; OR 1.19, 95%CI 1.04-1.37 for age 75-84; and OR 1.34, 95%CI 1.04-1.72 for age 85+). Advanced stage, female sex, and lower income levels were associated with higher odds of moderate/severe tiredness, anxiety, and lack of well-being in adjusted models. Patients with pancreatic and lung cancers reported worse scores for these three symptoms than patients with other cancers. DISCUSSION: Older age was associated with differences in symptom experiences such as increased tiredness and reduced anxiety. Supportive care interventions and future research should focus on addressing these symptoms to improve patient quality of life.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Masculino , Humanos , Femenino , Anciano , Anciano de 80 o más Años , Calidad de Vida , Depresión/epidemiología , Depresión/diagnóstico , Neoplasias/terapia , Dolor , Ansiedad/epidemiología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/complicaciones , Fatiga/epidemiología , Fatiga/etiología , Cuidados Paliativos
6.
Environ Sci Pollut Res Int ; 30(25): 66800-66811, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37099113

RESUMEN

In this study, PDMS incorporated with SWCNTs have been fabricated via solution casting method for industrial applications and characterized by the analyses of SEM, FTIR, TGA, AFM, and MST. The modified membranes were further analyzed for CO2, O2, and N2 gas permeability. The strategic membranes have five different weight ratios (0.013, 0.025, 0.038, 0.050, 0.063) compared to neat PDMS membranes. The even distribution of SWCNTs in PDMS provided results that showed improvement in thermal stability. However, mechanical strength has been weakened with increased concentration of nanofiller because of the increase in the number of SWCNTs by increases that imperfections become more severe. The designed polymeric membranes with good thermal stability and adequate mechanical strength can be used for the selectivity and permeability of CO2, O2, and N2 gases. The effect of the PDMS-SWCNTs on gas permeability has been studied. 0.063 wt.% SWCNTs presented the maximum permeability of CO2 gas while maximum O2 and N2 gas permeability have been obtained by 0.013 wt.% SWCNTs. The ideal selectivity of mixed (50:50) gas conditions has been tested. The maximum CO2/N2 ideal selectivity was obtained by 0.050 and 0.063 wt.% SWCNTs while maximum O2/N2 ideal selectivity obtained by 0.050 wt.% SWCNTs. Therefore, the fabrication of this novel SWCNTs-PDMS membrane may lead to separating the industrial exhaust and be used as a potential membrane for environmental remediation in the future.


Asunto(s)
Dióxido de Carbono , Nanotubos de Carbono , Dimetilpolisiloxanos , Gases , Permeabilidad
7.
Environ Sci Pollut Res Int ; 30(13): 36646-36662, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36550251

RESUMEN

Energy sustainability plays a crucial role in the development of any country. With the booming economy of Turkey, it is necessary to ensure energy sustainability in every sector. The residential sector plays a vital role in energy consumption in Turkey and improving sustainability in this sector can foster Turkey's development. This study introduced first-time sustainability indicators of Turkey's residential sector to determine the energy and exergy analyses through a thermodynamics-derived approach based on the data from 2000 to 2017. Monte Carlo simulations have been performed for energy source variation. Possible distribution uncertainties show that natural gas (0.78-0.76), biofuels, and waste (0.39-0.43) are dominant parameters for energy and exergy. Improvement of biofuels and waste, renewable-based energy sources can be a feasible solution for fossil fuel replacement. In Turkey's residential sector, energy efficiency varies from 27.51 to 35.65%, while exergy efficiency ranges from 25.85 to 34.06%. The sustainability index for Turkey ranges from 1.34 to 1.51. In Turkey, around 65.93 to 74.14% of fossil fuel has been depleted in the last 18 years, which leads to lesser exergetic sustainability. Inefficient cooking, heating appliances, and lighting devices lead to higher exergy loss. Therefore, this study demonstrates the exergy analysis and prediction of the upcoming consequences of this analysis. In the future, Turkey can use higher efficient devices, especially in heating, lighting, and mechanical energy-related appliances, and electricity can be used to attain higher exergetic efficiency. Performed analysis and uncertainties of parameters will assist policymakers in selecting suitable alternative strategies in Turkey's residential sector for sustainable decision-making.


Asunto(s)
Biocombustibles , Fuentes Generadoras de Energía , Turquía , Termodinámica , Combustibles Fósiles
9.
Biotechnol Adv ; 57: 107933, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35257785

RESUMEN

Recent advances in microalgae to biohythane (bio-H2 and bio-CH4) conversion have achieved growing attention due to their eco-friendly and energy-efficient nature. Although microalgae are considered a potential 3rd - 4th generation biomass, their low C/N ratio and cell-wall biopolymers are challenging for biohythane production. This study emphasizes the solutions to mitigate the adverse effects of microalgae-based biohythane production using co-digestion with wastewater sludge. Wastewater sludge, an emerging environmental concern, is reviewed to be an effective co-substrate with microalgae to establish a biorefinery approach. The future trends and prospects of this biorefinery approach is critically reviewed to attain a profitable process. This study also reviewed the advantages of microalgae-wastewater co-cultivation and the application of activated sludge for bio-flocculation as a cost-effective solution for microalgae cultivation and harvesting. Microalgae-wastewater co-cultivation is also recommended to be effective for biohythane purification. The liquid digestate is suggested to be used as a culture media to enhance microalgal growth; whereas, the solid digestate could be transformed into resources through hydrothermal processes as a solution of digestate management. A practical biorefinery approach combining the synergistic benefits of microalgae-wastewater sludge and its biological conversion to biohythane would be an adjoining link to the beginning of a sustainable future.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Digestión , Aguas del Alcantarillado , Aguas Residuales
10.
Chemosphere ; 291(Pt 3): 132760, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34740697

RESUMEN

Major agricultural solid waste, rice husk (RH)-based mesoporous materials were prepared by potassium hydroxide (KOH) treatment of RH and RH hydrochar (RHH) produced at 180 °C with 20 min reaction time. In this study, RH was treated with three different methods: RH activation by KOH (KOH-RH), RH activation by KOH-aqueous silver (Ag)-shell nanoparticle (AgNP) incorporation followed calcination at 550 °C for 2 h (AgNP-KOH-RH) and hydrothermally carbonized RH activation by KOH (KOH-RHH). The main objective of this study was to determine the effect of KOH activation with different synthesis approaches and compare the characterization results of RH based porous material to identify the potential adsorbent application for wastewater treatment. Therefore, after activation in different methods, all interactive properties such as elemental, chemical, structural, morphological, and thermal analyses were investigated comprehensively for all samples. The crystallinity peak intensity around 22°λ at the angle of diffraction of 2θ confirmed the presence of silica, higher stability of the material, and removal of organic components during the KOH activation. AgNP-KOH-RH and KOH-RHH presented high porosity on the outer surface. The presence of negligible volatile matter in KOH-RHH by TGA demonstrated the decomposition of organic compound. Very high ratio of aromatic carbon and lignin content by FTIR and XPS analysis in both AgNP-KOH-RH and KOH-RHH showed these two samples have improved stability. Very high negative surface charge (zeta potential) in AgNP-KOH-RH (-43.9 mV) and KOH-RHH (-43.1 mV) indicated the enhanced water holding capacity. Surface area for all experimented porous materials has been enhanced after KOH activation, where KOH-RHH demonstrated the maximum surface area value, 27.87 m2/g. However, AgNP-KOH-RH presented maximum pore diameter, 18.16 nm, and pore volume, 0.12 cm3/g. Hence, it can be concluded that both KOH-RHH and AgNP-KOH-RH have the potential to be implemented as wastewater adsorbents.


Asunto(s)
Nanopartículas del Metal , Oryza , Purificación del Agua , Hidróxidos , Porosidad , Compuestos de Potasio , Plata
11.
Sci Total Environ ; 811: 152295, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-34896490

RESUMEN

COVID-19 pandemic-borne wastes imposed a severe threat to human lives as well as the total environment. Improper handling of these wastes increases the possibility of future transmission. Therefore, immediate actions are required from both local and international authorities to mitigate the amount of waste generation and ensure proper disposal of these wastes, especially for low-income and developing countries where solid waste management is challenging. In this study, an attempt is made to estimate healthcare waste generated during the COVID-19 pandemic in Bangladesh. This study includes infected, ICU, deceased, isolated and quarantined patients as the primary sources of medical waste. Results showed that COVID-19 medical waste from these patients was 658.08 tons in March 2020 and increased to 16,164.74 tons in April 2021. A top portion of these wastes was generated from infected and quarantined patients. Based on survey data, approximate daily usage of face masks and hand gloves is also determined. Probable waste generation from COVID-19 confirmatory tests and vaccination has been simulated. Finally, several guidelines are provided to ensure the country's proper disposal and management of COVID-related wastes.


Asunto(s)
COVID-19 , Eliminación de Residuos Sanitarios , Residuos Sanitarios , Administración de Residuos , Bangladesh/epidemiología , Atención a la Salud , Humanos , Pandemias , SARS-CoV-2
12.
Materials (Basel) ; 15(12)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35744201

RESUMEN

The purpose of this study was to measure the strength of various bamboo fibres and their epoxy composites based on the bamboo ages and harvesting seasons. Three representative samples of 1-3-year-old bamboo plants were collected in November and February. Bamboo fibres and their epoxy composites had the highest tensile strength and Young's modulus at 2 years old and in November. The back-calculated tensile strengths using the "rule of mixture" of Injibara, Kombolcha, and Mekaneselam bamboo-fibre-reinforced epoxy composites were 548 ± 40-422 ± 33 MPa, 496 ± 16-339 ± 30 MPa, and 541 ± 21-399 ± 55 MPa, whereas the back-calculated Young's moduli using the "rule of mixture" were 48 ± 5-37 ± 3 GPa, 36 ± 4-25 ± 3 GPa, and 44 ± 2-40 ± 2 GPa, respectively. The tensile strengths of the Injibara, Kombolcha, and Mekaneselam bamboo-fibre-reinforced epoxy composites were 227 ± 14-171 ± 22 MPa, 255 ± 18-129 ± 15 MPa, and 206 ± 19-151 ± 11 MPa, whereas Young's moduli were 21 ± 2.9-16 ± 4.24 GPa, 18 ± 0.8-11 ± 0.51 GPa, and 18 ± 0.85-16 ± 0.82 GPa respectively. The highest to the lowest tensile strengths and Young's moduli of bamboo fibres and their epoxy composites were Injibara, Mekaneselam, and Kombolcha, which were the local regional area names from these fibres were extracted. The intended functional application of the current research study is the automobile industries of headliners, which substitute the conventional materials of glass fibres.

13.
Chemosphere ; 301: 134711, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35487351

RESUMEN

Bacterial contamination is one of the leading causes of water pollution. Antibacterial polyurethane/cellulose acetate membranes modified by functionalized TiO2 nanoparticles were processed and studied. TiO2 nanoparticles were prepared and ultraviolet (UV) irradiated to activate their photocatalytic activity against Escherichia coli (E. Coil) and Methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Functionalized TiO2 nanoparticles were incorporated in flat-sheet mixed matrix membranes (MMMs). These membranes were characterized for their different properties such as morphology, thermal stability, mechanical strength, surface wettability, water retention, salt rejection, water flux, and their antibacterial performance against E. Coil and MRSA was also tested. The activity of nanoparticles against MRSA and E. coli was analyzed using three different concentrations, 0.5 wt%, 1.0 wt% and 1.5 wt% of nanoparticles and 0.5 wt% of TiO2 nanoparticles showed maximum growth of bacteria. The maximum inhibition was observed in membranes with maximum nanoparticles when compared with other membranes. All these characteristics were strongly affected by increasing the concentration of TiO2 nanoparticles in the prepared membranes and the duration of their UV exposure. Hence, it was proved from this analysis that these TiO2 modified membranes exhibit substantial antibacterial properties. The results are supporting the utilization of these materials for water purification purposes.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Purificación del Agua , Antibacterianos/farmacología , Celulosa/análogos & derivados , Escherichia coli , Poliuretanos , Titanio/farmacología
14.
Materials (Basel) ; 15(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35888483

RESUMEN

Ethiopia has a large coverage of bamboo plants that are used for furniture making and house building. So far, researchers have not studied the strength of Ethiopian bamboo fibers, which are utilized for composite applications. The current study measured the strength of bamboo fibers based on various testing lengths and calculated the predictive tensile strength using a modified Weibull distribution. Moreover, the quality of the extraction machine is evaluated based on shape and sensitivity parameters. This research paper incorporates the coefficient of variation of the fiber diameters, considering the defects distribution through the length for measuring the predictive strength of the fibers. The fiber diameters were calculated using the area weight methods, which had its density measured using a Pycnometer. It has been examined that as the testing gauge length and coefficient variation of fiber diameter simultaneously increased, the tensile strength of the bamboo fibers decreased. The shape parameter, sensitivity parameter, and characteristic strength of Injibara bamboo (Y. alpina) are 6.02-7.83, 0.63, and 459-642 MPa, whereas Kombolcha bamboo (B. oldhamii) are 5.87-10.21, 0.33, and 408-638 MPa, as well as Mekaneselam bamboo (Y. alpina) are 5.86-9.63, 0.33 and 488-597 MPa, respectively.

15.
Materials (Basel) ; 15(13)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35806551

RESUMEN

Special attention is required when joining two materials with distinct chemical, physical and thermal properties in order to make the joint bond robust and rigid. The goal of this study was to see how significantly different tungsten inert gas (TIG) welding process parameters (welding current, gas flow rate, root gap, and filler materials) affect mechanical properties (tensile, hardness, and flexural strength), as well as the bead width and microstructural properties, of dissimilar welds In comparison to SS 316 and AISI 1020 low-carbon steel. TIG welding parameters were optimized in this study using a Taguchi-based desirability function analysis (DFA). From the experimental results, it was observed that welded samples employing ER-309L filler wires had a microstructure consisting of a delta ferrite network in an austenite matrix. The tensile strength experimental results revealed that welding current, followed by GFR, was a highly influential parameter on tensile strength. Weld metals had higher hardness and flexural strength than stainless steel and carbon steel base metals. This was supported by the fact that the results of our tests had hardness ratings greater than a base for the FZ and HAZ, and that no crack was observed in the weld metal following U-shape flexural bending. Welding current has a significant impact on the bead width of welded specimens, followed by root gap. Furthermore, the dissimilar welded sample responses were optimized with a composite desirability percentage improvement of 22.90% by using a parametric setting of (A2B4C4D2). Finally, the validation of the experiment was validated by our confirmation test results, which agreed with the predictive optimum parameter settings.

16.
Materials (Basel) ; 15(13)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35806552

RESUMEN

The output of the latent heat storage devices (LHSDs), based on some phase change materials (PCMs), depends upon the thermophysical properties of the phase change material used. In this study, a paraffin-based nanofluid, blended with aluminum oxide (Al2O3) nanoparticles, is used as PCM for performance evaluation. A three-dimensional (3D) numerical model of regenerative type shell-and-tube LHSD is prepared using COMSOL Multiphysics® 4.3a software to estimate the percentage of melt and the average temperature of the analyzed nanofluids. The results of this study are in close agreement with those reported in the literature, thereby ensuring the validation of the numerically predicted results. The effects of adding the nanoparticles on the rate of melting, as well as solidification and rate of stored/liberated energy, are studied. The results revealed that, by adding 10% nanoparticles of Al2O3, the melting rate of pure-paraffin-based LHSD improved by about 2.25 times. In addition, the rate of solidification was enhanced by 1.8 times. On the other hand, the heat of fusion and specific heat capacities were reduced, which, in turn, reduced the latent and sensible heat-storing capabilities. From the outcomes of the present research, it can be inferred that combining LHSD with a solar water heater may be used in technologies such as biogas generation.

17.
Polymers (Basel) ; 14(13)2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35808778

RESUMEN

The current studies aim to measure the mechanical strength based on age, harvesting season and bamboo species in Ethiopia. The bamboo fibres are extracted using a roll milling machine, which was developed by the author. The age groups (1, 2 and 3 years), harvesting months (February and November), and bamboo species (Yushania alpina and Bambusa oldhamii) are the parameters of the current research studies. Prepregs and composites were produced from bamboo fibres and polypropylene. The mechanical properties of bamboo fibres and their composites in Ethiopia have not been investigated by researchers for the composite application so far. The tensile strength, Young's modulus, and impact strength of injibara (Y. alpina) bamboo fibres reinforced PP composites from the ages of 1- 3 years old in November is 111 ± 9-125 ± 8 MPa, 15 ± 0.9-25 ± 0.72 GPa, and 47 ± 5 KJ/m2-57 ± 6 KJ/m2, whereas, in February, it is 86 ± 3.86-116 ± 10 MPa, 11 ± 0.71-23 ± 1.5 GPa, and 34 ± 4-52 ± 6 KJ/m2, respectively. Moreover, Kombolcha (B. oldhamii), bamboo fibres reinforced PP composites in November are 93 ± 7-111 ± 8 MPa, 7 ± 0.51-17 ± 2.56 GPa, and 39 ± 4-44 ± 5 KJ/m2, whereas, in February, it is 60 ± 5-104 ± 10 MPa, 12 ± 0.95-14 ± 0.92 GPa, and 26 ± 3 KJ/m2-38 ± 4 KJ/m2, respectively. Furthermore, Mekaneselam (Y. alpina) bamboo fibres reinforced PP composites in November are 99 ± 8-120 ± 11 MPa, 9 ± 0.82-16 ± 1.85 GPa, and 37 ± 4 KJ/m2-46 ± 5 KJ/m2, whereas, in February, it is 91 ± 8-110 ± 9 MPa, 8 ± 0.75-14 ± 1.86 GPa, and 34 ± 3 KJ/m2-40 ± 4 KJ/m2, respectively. At two years, November and Injibara bamboo have recorded the highest mechanical properties in the current research studies. Bamboo fiber strength in Ethiopia is comparable to the previous study of bamboo fibres and glass fibres used for composite materials in the automotive industry.

18.
Curr Oncol ; 29(2): 853-868, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-35200572

RESUMEN

BACKGROUND: There are no guidelines available for what assessment tools to use in a patient's self-completed online geriatric assessment (GA) with management recommendations. Therefore, we used a modified Delphi approach with Canadian expert clinicians to develop a consensus online GA plus recommendations tool. METHODS: The panel consisted of experts in geriatrics, oncology, nursing, and pharmacy. Experts were asked to rate the importance and feasibility of assessments and interventions to be included in an online GA for patients. The items included in the first round were based on guidelines for in-person GA and literature review. The first two rounds were conducted using an online survey. A virtual 2 h meeting was held to discuss the items where no consensus was reached and then voted on in the final round. RESULTS: 34 experts were invited, and 32 agreed to participate. In round 1, there were 85 items; in round 2, 50 items; and in round 3, 25 items. The final tool consists of fall history, assistive device use, weight loss, medication review, need help taking medication, social supports, depressive symptoms, self-reported vision and hearing, and current smoking status and alcohol use. CONCLUSION: This first multidisciplinary consensus on online GA will benefit research and clinical care for older adults with cancer.


Asunto(s)
Evaluación Geriátrica , Oncología Médica , Anciano , Canadá , Consenso , Técnica Delphi , Humanos
19.
Chemosphere ; 288(Pt 2): 132450, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34624353

RESUMEN

Biodiesel commercialization is questionable due to poor brake thermal efficiency. Biodiesel utilization should be improved with the addition of fuel additives. Hydrogen peroxide is a potential fuel additive due to extra hydrogen and oxygen content, which improves the combustion process. In this experimental study, biodiesel has been produced from Jatropha oil employing catalyzed transesterification homogeneously to examine its influence on the performance and emissions at engine loads with 1500 rpm utilizing a four-stroke single-cylinder diesel engine. D60B40 (having 60% diesel and 40% biodiesel) and D60B30A10 (60% diesel, 30% biodiesel and 10% hydrogen peroxide (H2O2)), are the fuel mixtures in the current study. The addition of H2O2 reduces emissions and enhances the combustion process. This effect occurred due to the micro-explosion of the injected fuel particles (which increases in-cylinder pressure and heat release rate (HRR)). An increase of 20% in BTE and 25% reduction in BSFC for D60B30A10 was observed compared to D60B40. Significant reduction in emissions of HC up to 17.54%, smoke by 24.6% CO2 by 3.53%, and an increase in NOx was noticed when the engine is operated with D60B30A10. The HRR increased up to 18.6%, ID reduced by 10.82%, and in-cylinder pressure increased by 8.5%. Test runs can be minimized as per Taguchi's design of experiments. It is possible to provide the estimates for the full factorial design of experiments. Exhaust gas temperature standards are evaluated and examined for all fuel blends.


Asunto(s)
Biocombustibles , Peróxido de Hidrógeno , Proyectos de Investigación
20.
J Am Geriatr Soc ; 70(4): 1268-1279, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34902156

RESUMEN

BACKGROUND: With the development of electronic geriatric assessment (GA), recommendations for self-management can be provided to patients without the presence of health care providers. Our research question was to identify what self-management interventions can be used by patients to address issues identified in GA and to determine their effect on patient-centered outcomes such as quality of life, health, mood, cognition, and functional status. METHODS: Searches were conducted on July 13, 2021, by a health sciences librarian in Medline, Embase, CINAHL, PsycInfo, and the Cochrane Library. A combination of database-specific subject headings and text word searches was used such as self-management, a key word for each of the geriatric assessment domains and older adults. Two independent reviewers reviewed abstracts and full texts for inclusion and abstracted data. Narrative synthesis was used to summarize findings. RESULTS: Among 28,520 abstracts reviewed, 34 randomized controlled trials were included. The most frequently studied geriatric domains were mood (n = 13 studies), mobility/falls (n = 12), quality of life (n = 11), and functional status (n = 7). The majority of studies demonstrated positive effects on mobility/falls (9 of 12), pain (3 of 5), comorbidity (4 of 4), and medication management (4 of 4). Most studies were of low to moderate quality. All geriatric domains were targeted in at least one study. CONCLUSIONS: Low- to moderate-quality studies show a variety of effective self-efficacy-targeted interventions exist for older adults to improve several important geriatric domains and related outcomes. However, long-term effects, validation, and scalability of these interventions remain largely unknown.


Asunto(s)
Automanejo , Anciano , Humanos , Evaluación de Resultado en la Atención de Salud , Calidad de Vida
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