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1.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(7): 813-817, 2024 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-39013817

RESUMO

Objective: To explore the method of preventing heat steam induced skin damage in robotic nipple-sparing mastectomy and immediate breast reconstruction (R-NSM-IBR) using Da Vinci Robots. Methods: A clinical data of 128 female patients with breast cancer, who were treated with R-NSM-IBR between September 2022 and December 2023 and met the selection criteria, was retrospectively analyzed. During robotic nipple-sparing mastectomy, the breasts were covered with gauze cooled by ice water to reduce skin temperature in 99 cases (group A) and were not treated in 29 cases (group B). There was no significant difference in the age, affected side, body mass index, pathological type of breast cancer, and constituent ratios of adjuvant chemotherapy and neoadjuvant chemotherapy between the two groups ( P>0.05). Intraoperative breast skin temperature, unilateral robotic nipple-sparing mastectomy time, and the incidence of complications of breast heat steam induced skin damage were recorded. Results: The time for unilateral robotic nipple-sparing mastectomy was (77.18±9.23) minutes in group A and (76.38±12.88) minutes in group B, with significant difference between the two groups ( P<0.05). The intraoperative breast skin temperature was significantly lower in group A than in group B [(25.61±0.91)℃ vs (33.38±1.14)℃; P<0.05]. Seven cases of heat steam skin damage occurred during operation, including 2 cases (2.0%) in group A and 5 cases (17.2%) in group B, with a significant difference in incidence between the two groups ( P<0.05). Among them, 1 patient in group B had a vesication rupture and infection, which eventually led to the removal of the implant; the rest of the patients were treated with postoperative interventions for skin recovery. Conclusion: The use of breast covered with gauze cooled by ice water during R-NSM-IBR can effectively reduce the risk of heat steam induced skin damage.


Assuntos
Neoplasias da Mama , Mamoplastia , Mamilos , Procedimentos Cirúrgicos Robóticos , Humanos , Feminino , Neoplasias da Mama/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Estudos Retrospectivos , Mamoplastia/métodos , Vapor , Temperatura Alta , Pele , Temperatura Cutânea , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Mastectomia/métodos , Mastectomia/efeitos adversos , Pessoa de Meia-Idade
2.
Bioresour Technol ; 406: 131058, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971389

RESUMO

Previous research on Char reactions with gas phase compounds under micro-thermogravimetry systems shows that hydrogen inhibits heterogeneous char reactions. However, its impact on larger gasification systems with evolving hydrogen profiles remains largely unexplored. This study examines a macro-scale wood char bed to understand the influence of in situ evolving hydrogen on char reactions. When subjected to a specific steam flux, carbon conversion and pore morphology changes are mainly confined to the bed's upstream, with the downstream char retaining its original characteristics. Numerical investigations reveal over 75 % of species production and consumption occurs within the initial 20 % of bed height. Fourier-transform infrared spectroscopy confirms hydrogen-induced inhibition in downstream segments, showing a shift from C-OH to C-H bonds. Particle-scale analysis indicates significantly higher rates of hydrogen diffusion and adsorption compared to H2O, impeding downstream C+H2O reactions. Increased temperature, higher reactant concentrations, or reduced residence time can overcome this inhibition, enhancing conversion rates. These findings are critical for optimizing steam-to-biomass ratios in oxy-steam gasification systems for generating hydrogen-rich syngas.


Assuntos
Carbono , Hidrogênio , Água , Madeira , Hidrogênio/química , Madeira/química , Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Carvão Vegetal/química , Vapor , Temperatura
3.
Proc Natl Acad Sci U S A ; 121(30): e2400425121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012818

RESUMO

In the centuries following Christopher Columbus's 1492 voyage to the Americas, transoceanic travel opened unprecedented pathways in global pathogen circulation. Yet no biological transfer is a single, discrete event. We use mathematical modeling to quantify historical risk of shipborne pathogen introduction, exploring the respective contributions of journey time, ship size, population susceptibility, transmission intensity, density dependence, and pathogen biology. We contextualize our results using port arrivals data from San Francisco, 1850 to 1852, and from a selection of historically significant voyages, 1492 to 1918. We offer numerical estimates of introduction risk across historically realistic ranges of journey time and ship population size, and show that both steam travel and shipping regimes that involved frequent, large-scale movement of people substantially increased risk of transoceanic pathogen circulation.


Assuntos
Navios , Viagem , Humanos , Vapor , Modelos Teóricos , São Francisco/epidemiologia , História do Século XX , História do Século XIX
4.
J Food Sci ; 89(7): 4345-4358, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38853294

RESUMO

Freezing is a crucial step in the process of frozen foods. In this study, the effects of different freezing methods, including liquid nitrogen immersion freezing (LF), quick-freezing machine freezing (QF), packaging immersion freezing (PF), and ultralow temperature refrigerator freezing (UF), and freezing time (0, 15, 30, and 60 days) on the textural properties, dynamic rheological properties, water distribution, and structure of dough and the quality of end steamed bread were evaluated. Freezing resulted in a decline in the physicochemical properties of dough. UF- and QF-doughs had higher storage modulus and loss modulus, compared with PF- and LF-doughs. LF enhanced the textural attributes of the dough, resulting in reduced hardness and increased springiness. At 15 days of freezing, QF- and LF-doughs exhibited a compact and continuous structure with a smooth surface. Additionally, the correlation analysis elucidated that the weight loss rate and the bound water content of the dough had discernible impacts on the texture of both the dough and the resulting steamed bread. Overall, LF demonstrated a relatively high freezing efficiency and effectively maintained the quality of the dough for up to 15 days of freezing. These results offer valuable insights for the applications of freezing methods and time in frozen foods.


Assuntos
Pão , Farinha , Manipulação de Alimentos , Congelamento , Reologia , Pão/análise , Manipulação de Alimentos/métodos , Farinha/análise , Água/análise , Vapor , Dureza
5.
Int J Biol Macromol ; 273(Pt 1): 132918, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38844282

RESUMO

Manufacturing biodegradable lignocellulosic films from spent coffee grounds (SCG) as an alternative to commercial plastics is a viable solution to address plastic pollution. Here, the biodegradable lignocellulosic films from SCG were fabricated via a sequential alkaline treatment and ionic liquid-based dissolution process. The alkaline treatment process could swell the cell wall of SCG, change its carbohydrates and lignin contents, and enhance its solubility in ionic liquids. The prepared SCG films with different lignin contents exhibited outstanding UV blocking capability (42.07-99.99 % for UVB and 20.96-99.99 % for UVA) and light scattering properties, good surface hydrophobicity (water contact angle = 63.2°-88.7°), enhanced water vapor barrier property (2.28-6.79 × 10-12 g/m·s·Pa), and good thermal stability. Moreover, the SCG films exhibit excellent mechanical strength (50.10-81.56 MPa, tensile strength) and biodegradability (fully degraded within 30 days when buried in soil) compared to commercial plastic. The SCG films represent a promising alternative that can replace non-biodegradable plastics.


Assuntos
Café , Lignina , Plásticos , Lignina/química , Café/química , Plásticos/química , Interações Hidrofóbicas e Hidrofílicas , Resistência à Tração , Biodegradação Ambiental , Solubilidade , Permeabilidade , Plásticos Biodegradáveis/química , Vapor , Resíduos
6.
Int J Biol Macromol ; 273(Pt 2): 132956, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848838

RESUMO

Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively. The inclusion of glycerol exerted a plasticizing influence on the mechanical properties of the films, while keeping their transparency. Hydrodynamic and barrier properties were assessed through water uptake and water vapor/oxygen transmission rates, respectively, and obtained values were consistent with those of other cellulose-based materials. Furthermore, overall migration levels were below European regulation limits, as stated by using Tenax® as a dry food simulant. In addition, these bioplastics demonstrated good greaseproof performance, particularly at high glycerol content, and potential as packaging materials for bakery products. Biodegradability assessments were carried out by measuring the biological oxygen demand in seawater and high biodegradation rates induced by glycerol were observed.


Assuntos
Celulose , Embalagem de Alimentos , Glicerol , Embalagem de Alimentos/métodos , Glicerol/química , Celulose/química , Plásticos/química , Plastificantes/química , Vapor , Água/química , Biodegradação Ambiental , Plásticos Biodegradáveis/química
7.
Int J Biol Macromol ; 273(Pt 2): 132951, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848851

RESUMO

The current work focuses on developing nanocomposite films using taro starch and cellulose nanofibers extracted from the root's peel. Films were prepared using mixtures of starch, cellulose nanofibers (0 %, 5 %, 10 %, and 15 % w/w), glycerol, and water. Results showed that the addition of cellulose nanofibers increased film thickness, opacity, UV-light barrier capacity, and water swelling percentage. All films showed a typical B-type X-ray diffraction pattern characteristic of semicrystalline materials. FTIR analysis confirmed chemical interactions between the starch chains and the nanofibers, which probably interact through hydrogen bonds. Nanocomposite films exhibited increased tensile strength and reduced strain at break compared to control materials. Films with cellulose nanofibers showed an increase in Young's modulus compared to control ones, with no differences observed between films with cellulose nanofibers at 10 % and 15 %. Furthermore, films with cellulose nanofibers at 5 % and 10 % exhibited lower water vapor permeability than control samples, while those with cellulose nanofibers at 15 % showed an increase in this parameter compared to other materials. These results suggest that incorporating taro cellulose nanofibers is a promising alternative for obtaining taro starch nanocomposites films with improved properties.


Assuntos
Celulose , Nanocompostos , Nanofibras , Permeabilidade , Amido , Nanofibras/química , Nanocompostos/química , Celulose/química , Amido/química , Resistência à Tração , Vapor , Água/química , Difração de Raios X
8.
Int J Biol Macromol ; 273(Pt 1): 133056, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862058

RESUMO

Solar steam generation (SSG) offers a sustainable approach to fresh water production. Herein, a novel dual-functional natural rubber/carbon black composite foam evaporator is presented for a cost-efficient SSG system that both produces fresh water and eliminates heavy metals present in the water. The composite foam is produced using the Dunlop process, and in its optimized form, it absorbed >96 % of sunlight. The foam evaporator exhibited a thermal conductivity of 0.052 W/m⋅K, a water evaporation rate of 1.40 kg/m2/h, converted 83.38 % of light to heat under 1 sun irradiation, and showed outstanding stability. The technology required to produce this composite foam is already available to make large-scale production feasible, while the natural raw materials are abundant. On the basis of its performance qualities, the rubber foam composite appears to be an excellent candidate for application as a viable solar absorber for SSG to produce fresh, clean water for commercial purposes.


Assuntos
Metais Pesados , Borracha , Luz Solar , Borracha/química , Metais Pesados/química , Látex/química , Purificação da Água/métodos , Água/química , Descontaminação/métodos , Vapor , Poluentes Químicos da Água/química , Fuligem/química
9.
Int J Biol Macromol ; 273(Pt 2): 133110, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38876230

RESUMO

In food packaging, sodium lignosulfonate nanoparticles (SLS NPs) showed significant antibacterial properties, antioxidant and UV barrier activities. Herein, the SLS NPs were synthesized via a sustainable green method and were added into egg albumin/sodium alginate mixture (EA/SA) to fabricate a safe, edible EA/SA/SNPs food packaging. A composite film EA/SA/SNP was examined microstructurally and physicochemically. The mechanical characteristics, UV protection, water resistance, and the composite film's thermal stability were all enhanced by the inclusion of SLS NPs, and water vapor permeability reduced by 44 %. This composite film exhibited robust antioxidative properties with DPPH and ABTS free radical scavenging rates reaching 76.84 % and 92.56 %, and effective antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with antibacterial rates reaching 98.25 % and 97.13 % for the positively charged nanoparticles interacting with the cell membrane. Freshness tests showed that the EA/SA/SNPs packaging film could delay the quality deterioration of fresh tomatoes. This composite film can slow down spoilage bacteria proliferation and prolongs food's preservation period by eight days at ambient temperature.


Assuntos
Alginatos , Antibacterianos , Antioxidantes , Embalagem de Alimentos , Lignina , Nanopartículas , Alginatos/química , Alginatos/farmacologia , Embalagem de Alimentos/métodos , Nanopartículas/química , Antioxidantes/farmacologia , Antioxidantes/química , Antibacterianos/farmacologia , Antibacterianos/química , Lignina/química , Lignina/análogos & derivados , Lignina/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Permeabilidade , Vapor
10.
Int J Biol Macromol ; 273(Pt 2): 133196, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38885865

RESUMO

Gum arabic finds extensive application and typically undergoes sterilization prior to utilization in the food industry. This study explored the impact of steam sterilization temperature and duration on the physicochemical and emulsification characteristics of gum arabic, accompanied by proposed mechanisms elucidating observed effects. The results showed that when gum arabic was treated with high temperature sterilization (110 °C âˆ¼ 140 °C), the emulsion prepared turned unstable. The interfacial tension decreased from 8.26 mN/m to 6.77 mN/m after sterilization, while the elastic modulus decreased from 23.65 mN/m to 16.16 mN/m. Moreover, the circular dichroic chromatographic results indicated that the arabinogalactan protein (AGP) structure of gum arabic was more relaxed after high temperature treatment with ß-sheets content decreased from 36.2 % to 29.8 % and random coil content increased from 41.3 % to 51.8 %. Quartz crystal microbalance with dissipation (QCM-D) results demonstrated that emulsion surface film thickness and toughness decreased after sterilization treatment of gum arabic. The study indicates that high temperature sterilization may change protein structure in gum arabic and reduce the stability of prepared emulsions.


Assuntos
Emulsões , Goma Arábica , Vapor , Goma Arábica/química , Emulsões/química , Fenômenos Químicos , Proteínas de Plantas/química , Temperatura , Mucoproteínas/química , Esterilização/métodos , Tensão Superficial
11.
Food Res Int ; 190: 114661, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945592

RESUMO

Chinese steamed bread (CSB) is an important staple of the Chinese people, and its flavor profile is mostly affected by wheat varieties among others. This study selected wheat flour made from three different wheat varieties and investigated their contribution to the CSB flavor profile in terms of metabolism. Thirteen aroma-active compounds identified by GC-O were determined as the main contributors to the different aroma profiles of three CSBs. 350 sensory trait-related metabolites were obtained from five key modules via weighted gene co-expression network analysis. It was found that the sensory characteristics of CSBs made of different wheat flour were significantly different. The higher abundance of lipids in Yongliang No.4 (YL04) wheat flour was converted to large number of fatty acids in fermented dough, which led to the bitterness of CSB. Besides, the abundance in organic acids and fatty acids contributed to the sour, milky, wetness and roughness attributes of YL04-CSB. More fatty amides and flavonoids in Jiangsu Red Durum wheat flour contributed to the fermented and winey attributes of CSB. Carbohydrates with higher abundance in Canadian wheat flour was involved in sugar-amine reaction and glucose conversion, which enhanced the sweetness of CSB. In addition, fatty acids, organic acids, amino acids, and glucose were crucial metabolites which can further formed into various characteristic compounds such as hexanal, hexanol, 2,3-butanediol, acetoin, and 2,3-butanedione and thus contributed to the winey, fresh sweet, and green aroma properties. This study is conductive to better understand the evolution of the compounds that affect the quality and aroma of CSBs.


Assuntos
Pão , Farinha , Odorantes , Paladar , Triticum , Pão/análise , China , Ácidos Graxos/análise , Fermentação , Farinha/análise , Odorantes/análise , Vapor , Triticum/química , Compostos Orgânicos Voláteis/análise
12.
World J Urol ; 42(1): 383, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904777

RESUMO

PURPOSE: To investigate safety and feasibility of performing water vapor thermal therapy (WVTT; Rezum, Boston Scientific, Marlborough, MA, USA) without postoperative catheterization among men with benign prostatic hyperplasia. METHODS: This is a prospective, single arm, unblinded pilot study of 20 consecutive male patients ages 40-80 who underwent WVTT at a single academic institution. All patients underwent 1 injection per lobe at the point of maximal obstruction based on visualization. Primary outcome was evaluation of voiding parameters, symptom scores, and need for catheterization at 3 day, 1, 3, and 6 month follow up compared to baseline visit 30 days prior to surgery. RESULTS: Mean age was 65 years (range 55-75). Mean prostate volume and PVR were 43 cc (range 30-68) and 89 cc, with 30% (n = 6) having median lobes. Patients received 2-3 treatments based on presence of bilobar versus trilobar hyperplasia. One patient (55 cc prostate, no median lobe) required catheterization for acute urinary retention on postoperative day 2. No patients required antibiotics for urinary tract infection or inpatient readmission within 30 days. Qmax significantly increased from 6 mL/s to 8, 13, 12, and 14 at 3 days, 1, 3, and 6 months (p < 0.05). IPSS decreased from 17 preoperatively to 10, 6, 7, and 8 (p < 0.05). No significant differences were noted in PVR, IIEF, MSHQ-EjD, or SF-12. CONCLUSIONS: In well-selected men, catheter-free WVTT is feasible and improved voiding parameters and symptom scores. No changes in sexual function, infectious complications, or readmission were noted. Only 1 patient (5%) required postoperative catheterization within 30 days.


Assuntos
Estudos de Viabilidade , Hiperplasia Prostática , Vapor , Humanos , Masculino , Hiperplasia Prostática/terapia , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Projetos Piloto , Resultado do Tratamento , Idoso de 80 Anos ou mais , Adulto , Hipertermia Induzida/métodos
13.
Biomed Mater ; 19(4)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38898715

RESUMO

This study investigated the potential of ethanolic garlic extract-loaded chitosan hydrogel film for burn wound healing in an animal model. The ethanolic garlic extract was prepared by macerating fresh ground garlic cloves in ethanol for 24 h, followed by filtration and concentration using a rotary evaporator. Hydrogels were then prepared by casting a chitosan solution with garlic extract added at varying concentrations for optimization and, following drying, subjected to various characterization tests, including moisture adsorption (MA), water vapor transmission rate (WVTR), and water vapor permeability rate (WVPR), erosion, swelling, tensile strength, vibrational, and thermal analysis, and surface morphology. The optimized hydrogel (G2) was then analyzedin vivofor its potential for healing 2nd degree burn wounds in rats, and histological examination of skin samples on day 14 of the healing period. Results showed optimized hydrogel (G2; chitosan: 2 g, garlic extract: 1 g) had MA of 56.8% ± 2.7%, WVTR and WVPR of 0.00074 ± 0.0002, and 0.000 498 946 ± 0.0001, eroded up to 11.3% ± 0.05%, 80.7% ± 0.04% of swelling index, and tensile strength of 16.6 ± 0.9 MPa, which could be attributed to the formation of additional linkages between formulation ingredients and garlic extract constituents at OH/NH and C=O, translating into an increase in transition melting temperature and enthalpy (ΔT= 238.83 °C ± 1.2 °C, ΔH= 4.95 ± 0.8 J g-1) of the chitosan moieties compared with blank. Animal testing revealed G2 formulation significantly reduced the wound size within 14 d of the experiment (37.3 ± 6.8-187.5 ± 21.5 mm2) and had significantly higher reepithelization (86.3 ± 6.8-26.8 ± 21.5 and 38.2% ± 15.3%) compared to untreated and blank groups by hastening uniform and compact deposition of collagen fibers at the wound site, cementing developed formulation a promising platform for skin regeneration.


Assuntos
Queimaduras , Quitosana , Alho , Hidrogéis , Extratos Vegetais , Pele , Resistência à Tração , Cicatrização , Animais , Quitosana/química , Cicatrização/efeitos dos fármacos , Ratos , Alho/química , Queimaduras/terapia , Queimaduras/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Pele/patologia , Masculino , Hidrogéis/química , Etanol/química , Regeneração/efeitos dos fármacos , Permeabilidade , Vapor , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Metilgalactosídeos
14.
Urol Pract ; 11(4): 727-734, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38899675

RESUMO

INTRODUCTION: Water vapor thermal therapy (WVTT) is a minimally invasive therapy designed to treat lower urinary tract symptoms associated with benign prostatic hyperplasia. Long-term outcomes with large (>80 cc) and small (<30 cc) prostate volumes (PVs) remain limited. We report 48-month outcomes for a multiethnic cohort of WVTT-treated men, stratified by PV. METHODS: In this single-center retrospective study, patients were stratified by PV: < 30 cc, 30 to 80 cc, or > 80 cc. Outcome measures, including International Prostate Symptom Score, quality of life, International Index of Erectile Function, medication usage, and adverse events, were analyzed at baseline and at 1-, 3-, 6-, 12-, 24-, 36-, and/or 48-month follow-up. RESULTS: Two hundred fifty-two patients met inclusion; 35 (13.9%) had PVs < 30 cc, 196 (77.8%) had PVs 30 to 80 cc, and 21 (8.3%) had PVs > 80 cc. Most patients were Asian (33.7%) or non-Hispanic Black (29.4%). International Prostate Symptom Score and quality of life improved in all cohorts from baseline at all follow-ups (all P < .05), with no differences between cohorts. International Index of Erectile Function-Orgasmic Function and -Erectile Function domains improved in 30 to 80 cc patients at 48 months. Alpha blocker and/or 5-alpha reductase inhibitor usage decreased at all follow-ups in < 30 cc and 30 to 80 cc patients and remained durable to only 6 months for > 80 cc patients. No significant differences in adverse events or reoperation rates were observed between cohorts. CONCLUSIONS: Our study suggests WVTT to be efficacious, durable, and safe in managing lower urinary tract symptoms across PVs, although PV > 80 cc patients may require benign prostatic hyperplasia medication at long-term follow-up. Further research is desired to clarify WVTT's role regarding sexual function and in treating men with larger PVs.


Assuntos
Próstata , Hiperplasia Prostática , Vapor , Humanos , Masculino , Hiperplasia Prostática/terapia , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Próstata/patologia , Tamanho do Órgão , Sintomas do Trato Urinário Inferior/terapia , Qualidade de Vida , Fatores de Tempo , Hipertermia Induzida/métodos
15.
Bioresour Technol ; 405: 130932, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838831

RESUMO

The first comparative pre-treatment study of Miscanthus (Mxg) and sugarcane bagasse (SCB) using steam explosion (SE) and pressurised disc refining (PDR) pretreatment to optimise xylose and xylo-oligosaccharide release is described. The current investigation aimed to 1) Develop optimised batch-wise steam explosion parameters for Mxg and SCB, 2) Scale from static batch steam explosion to dynamic continuous pressurised disc refining, 3) Identify, understand, and circumvent scale-up production hurdles. Optimised SE parameters released 82% (Mxg) and 100% (SCB) of the available xylan. Scaling to PDR, Miscanthus yielded 85% xylan, highlighting how robust scouting assessments for boundary process parameters can result in successful technical transfer. In contrast, SCB technical transfer was not straightforward, with significant differences observed between the two processes, 100% (SE) and 58% (PDR). This report underlines the importance of feedstock-specific pretreatment strategies to underpin process development, scale-up, and optimisation of carbohydrate release from biomass.


Assuntos
Celulose , Oligossacarídeos , Poaceae , Saccharum , Vapor , Xilose , Saccharum/química , Celulose/química , Projetos Piloto , Biotecnologia/métodos , Xilanos , Glucuronatos
16.
Med Sci Monit ; 30: e944502, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857196

RESUMO

BACKGROUND Before insertion, chairside adjustment kits are heat sterilized for positioning and polishing dental restorations. This study aimed to evaluate the effects of 2 steam sterilization cycles on the efficacy of polishing highly translucent monolithic zirconia (HTMLZ) dental restoration material. MATERIAL AND METHODS 100 HTMLZ disc-shaped specimens were adjusted (grinding, finishing, polishing) with EVE Diacera kit. Two steam sterilization techniques [standard (Gp S), immediate/flash (Gp (F)] of CAK were further subgrouped based on number of sterilization cycles [cycle 1 (control), cycle 5, 10, 15, and 20 (experimental)] (n=10 each). Each subgroup accordingly was evaluated for average surface roughness (Ra) and root mean square roughness (Rq) using a profilometer. Mean and standard deviation of 5 subgroups were statistically analyzed using one-way ANOVA/post hoc Tukey's test. Scanning electron microscopy complemented Ra, Rq measurements. Statistical differences of P≤0.05 were considered significant. RESULTS HTMLZ specimens in both groups showed increased (Ra/Rq) values after repeated sterilization of EVE Diacera kit, with Gp F showing lesser increase than Gp S (20 cycles). Gp F at 10 cycles and Gp S at 15 cycles showed clinically unacceptable roughness threshold (0.25 µm). Differences between subgroups for Ra and Rq values were significant (P≤0.05) with less differences within groups observed in early cycles (1, 10). Results validate the manufacturer's recommendations of using flash sterilization/10 cycles for EVE Diacera kit. CONCLUSIONS Repeated sterilization reduces efficacy of chairside adjustment kit to produce smooth surfaces on HTMLZ. This study recommends flash sterilization to a maximum of 10 times to get the clinically acceptable results of Ra and Rq.


Assuntos
Materiais Dentários , Polimento Dentário , Vapor , Esterilização , Propriedades de Superfície , Zircônio , Esterilização/métodos , Humanos , Polimento Dentário/métodos , Teste de Materiais/métodos , Restauração Dentária Permanente/métodos , Microscopia Eletrônica de Varredura/métodos
17.
Sci Rep ; 14(1): 13693, 2024 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871956

RESUMO

The present study utilized response surface methodology (RSM) to investigate the impact of varying concentrations of carboxymethyl cellulose (CMC: 0.75-1.75 wt%), Commiphora mukul polysaccharide (CMP: 0-1 wt%), and Chitosan Nanofiber (CHNF: 0-1 wt%) on the physical and antimicrobial characteristics of nanocomposite films based on CMC. The optimization process aimed to enhance ultimate tensile strength (UTS), strain at break (SAB), and antibacterial activity, while minimizing water vapor permeability (WVP), solubility, swelling, moisture content, opacity, and total color difference (ΔE). The results revealed that both CMP and CHNF had a positive influence on reducing moisture content, WVP, and increasing UTS. However, higher concentrations of CMP and CHNF had a divergent effect on SAB, ΔE, and swelling. The incorporation of CMP led to increased opacity and solubility, while the inclusion of CHNF resulted in decreased opacity and solubility. Notably, only CHNF addition significantly improved the antibacterial properties of the films. By applying the optimization procedure utilizing RSM, the formulation containing CMC (1.5 wt%), CMP (0.25 wt%), and CHNF (0.75 wt%) demonstrated superior physical, mechanical, and antibacterial properties in the biodegradable film matrix. These findings highlight the potential of utilizing these components to enhance the performance of CMC-based nanocomposite films.


Assuntos
Carboximetilcelulose Sódica , Quitosana , Nanocompostos , Nanofibras , Resistência à Tração , Quitosana/química , Carboximetilcelulose Sódica/química , Nanofibras/química , Nanocompostos/química , Antibacterianos/farmacologia , Antibacterianos/química , Gomas Vegetais/química , Polissacarídeos/química , Solubilidade , Commiphora/química , Permeabilidade , Vapor , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana
18.
Int J Biol Macromol ; 272(Pt 1): 132813, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825276

RESUMO

Bionanocomposite films of three biopolymers including chitosan, gelatin, and pectin incorporated with rosemary essential oil (REO) were developed and characterized in terms of their physical, structural, mechanical, morphological, antioxidant, and antimicrobial properties. Incorporation of REO showed an increased hydrophobic nature thus, improved water vapor transmission rate (WVTR), tensile strength (TS), elongation-at-break (EAB), and thermal stability significantly (P ≤ 0.05) as compared to the control films. The addition of REO leads to more opaque films with relatively increased microstructural heterogeneity, resulting in an increase in film opacity. Fourier transform infrared spectroscopy (FTIR) and particle size revealed that REO incorporation exhibits high physicochemical stability in chitosan, gelatin, and pectin bionanocomposite films. Incorporation of REO exhibited the highest inhibitory activity against the tested pathogenic strains (Bacillus subtilis and Escherichia coli). Furthermore, the addition of REO increased the inhibitory activity of films against ABTS and DPPH free radicals. Therefore, chitosan, gelatin, and pectin-based bionanocomposite films containing REO as food packaging could act as a potential barrier to extending food shelf life.


Assuntos
Antioxidantes , Quitosana , Embalagem de Alimentos , Gelatina , Nanocompostos , Óleos Voláteis , Pectinas , Quitosana/química , Pectinas/química , Gelatina/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Nanocompostos/química , Antioxidantes/química , Antioxidantes/farmacologia , Embalagem de Alimentos/métodos , Resistência à Tração , Vapor , Bacillus subtilis/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Int J Biol Macromol ; 272(Pt 1): 132817, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38834126

RESUMO

Multifunctional smart biopolymeric films were fabricated using rose petal anthocyanin (RPA) and carrageenan (CAR) doped with rose petal-derived carbon dots (RP-CDs). Response surface-optimized RPA showed the highest total anthocyanins and radical scavenging ability. Produced RP-CD exhibited UV absorption and high fluorescence with antibacterial/antioxidant abilities. Enrichment with 2 % RP-CD and 5 % RPA in the CAR matrix results in improved physicochemical, i.e., water contact angle, water vapor permeability, and UV-blocking properties of the fabricated material. Results showed that nanocomposite films scavenged radicals better than the neat CAR films. Zeta potential, FTIR, SEM, and XPS suggested improved compatibility/stability and enhanced elemental configuration of RP-CDs/RPA additives in the CAR polymer matrix. Perishable food packaging (minced pork and shrimp) demonstrated that nanocomposite films work efficiently and non-destructively and are promising tools for monitoring real-time freshness through interpretable visual changes from red to yellow. The CAR/RP-CDs/RPA-based nanocomposite indicator films are expected to be applied as various smart packaging materials. These films possess the ability to promptly detect changes in quality, preserve the quality, and prolong the shelf life of packaged foods.


Assuntos
Antocianinas , Carbono , Carragenina , Embalagem de Alimentos , Rosa , Embalagem de Alimentos/métodos , Antocianinas/química , Carragenina/química , Rosa/química , Carbono/química , Nanocompostos/química , Flores/química , Permeabilidade , Vapor , Antioxidantes/química , Pontos Quânticos/química , Antibacterianos/química , Antibacterianos/farmacologia
20.
J Environ Manage ; 365: 121588, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941851

RESUMO

There have been notable changes in precipitation patterns on the Loess Plateau (LP) of China in recent decades, and numerous attribution studies have focused on sea surface temperature anomalies and atmospheric circulation changes induced by aerosols and greenhouse gases emission. However, the influences of global land use and land cover change (LULCC) as an important forcing factor in the climate system on regional precipitation remains poorly understood. In this study, we quantified the impacts of LULCC on precipitation and the water vapor budget in the LP region, utilizing data from LULCC forcing experiments conducted by the sixth phase of the Coupled Model Intercomparison Project (CMIP6). Although global LULCC forcing exerted a negative effect on long-term mean precipitation on the LP region from 1850 to 2014, the different response characteristics were detected during different time periods. The global LULCC caused a decrease of 14 mm in annual precipitation during the period of 1850-1960. Conversely, from 1961 to 2014, it led to an increase of 6.4 mm, which is largely attributed to the enhanced water vapor transport along the southern boundary and westerly belt of the LP region. Moreover, from the perspective of the net water vapor balance of the entire LP, although LULCC caused net water vapor export during both periods 1850-1960 and 1961-2014, the export during the latter period (0.20 × 104 kg s-1) was smaller than that during the former period (0.28 × 104 kg s-1), indicating that the global expansion of grassland and cropland, along with the continuous rise in the leaf area index from 1961 to 2014, contributed to retaining more water vapor within the LP, which in turn was more favorable for precipitation. These findings provide valuable insights into the reasons behind precipitation variations in the LP region, emphasizing that global vegetation restoration and greening play a significant role in improving precipitation in ecologically fragile areas.


Assuntos
Vapor , China , Mudança Climática , Chuva
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