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1.
J Microsc ; 294(2): 203-214, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38511469

RESUMEN

Low-vacuum scanning electron microscopy (low-vacuum SEM) is widely used for different applications, such as the investigation of noncoated specimen or the observation of biological materials, which are not stable to high vacuum. In this study, the combination of mineral building materials (concrete or clay plaster) with a biological composite (fungal mycelium composite) by using low-vacuum SEM was investigated. Fungal biotechnology is increasingly gaining prominence in addressing the challenges of sustainability transformation. The construction industry is one of the biggest contributors to the climate crises and, therefore, can highly profit from applications based on regenerative fungal materials. In this work, a fungal mycelium composite is used as alternative to conventional insulating materials like Styrofoam. However, to adapt bio-based products to the construction industry, investigations, optimisations and adaptations to existing solutions are needed. This paper examines the compatibility between fungal mycelium materials with mineral-based materials to demonstrate basic feasibility. For this purpose, fresh and hardened concrete specimens as well as clay plaster samples are combined with growing mycelium from the tinder fungus Fomes fomentarius. The contact zone between the mycelium composite and the mineral building materials is examined by scanning electron microscopy (SEM). The combination of these materials proves to be feasible in general. The use of hardened concrete or clay with living mycelium composite appears to be the favoured variant, as the hyphae can grow into the surface of the building material and thus a layered structure with a stable connection is formed. In order to work with the combination of low-density organic materials and higher-density inorganic materials simultaneously, low-vacuum SEM offers a suitable method to deliver results with reduced effort in preparation while maintaining high capture and magnification quality. Not only are image recordings possible with SE and BSE, but EDX measurements can also be carried out quickly without the influence of a coating. Depending on the signal used, as well as the magnification, image-recording strategies must be adapted. Especially when using SE, an image-integration method was used to reduce the build-up of point charges from the electron beam, which damages the mycelial hyphae. Additionally using different signals during image capture is recommended to confirm acquired information, avoiding misinterpretations.


Asunto(s)
Minerales , Micelio , Microscopía Electrónica de Rastreo , Vacio , Arcilla , Micelio/química , Minerales/análisis , Materiales de Construcción
2.
Cell Mol Biol (Noisy-le-grand) ; 70(4): 29-34, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678631

RESUMEN

We hypothesized that the combined effect of vacuum packaging and Juniperi fructus essential oil addition would increase shelf life. Six different treatments were tested. The effects of the different concentrations of J. fructus essential oil (0%, 0.3% and 0.6%) and packing method (non-vacuum and vacuum) on the fish (Oncorhynchus mykiss) fillets of stored 4±1 °C were investigated in terms of its microbiological (mesophilic aerobic bacteria and yeast-mold), chemical (pH,  total volatile alkaline nitrogen (TVB-N), thiobarbituric acid (TBA value)) and sensory quality. The results showed that J. fructus essential oil had a positive significant effect on quality parameters (p<0.05). In conclusion, based primarily on sensory, TVB-N and mesophilic bacteria data the shelf-life of fresh rainbow trout was 4 days (non-vacuum packaged), 13 days (vacuum packaged), 19 and 28 days treated with J. fructus oil (0.3 and 0.6%, v/w) under vacuum packaged, respectively. J. fructus essential oil application and vacuum packaging; extended the shelf life of fish fillets by an average of 15 days. The combined use of J. fructus essential oil and packaging techniques could form the basis for new studies.


Asunto(s)
Embalaje de Alimentos , Conservación de Alimentos , Almacenamiento de Alimentos , Juniperus , Aceites Volátiles , Oncorhynchus mykiss , Animales , Aceites Volátiles/farmacología , Vacio , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Oncorhynchus mykiss/microbiología , Juniperus/química , Conservación de Alimentos/métodos , Concentración de Iones de Hidrógeno
3.
Environ Res ; 250: 118363, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38331141

RESUMEN

The widespread existence of antibiotics in the environment has attracted growing concerns regarding the potential adverse effects on aquatic organisms, ecosystems, and human health even at low concentrations. Extensive efforts have been devoted to developing new methods for effective elimination of antibiotics from wastewater. Herein, a novel process of Fe2+ catalytically enhanced vacuum ultraviolet (VUV) irradiation was proposed as a promising approach for the removal of antibiotic trimethoprim (TMP) in water. Compared with UVC photolysis, VUV photolysis, and UVC/Fe2+, VUV/Fe2+ could increase the pseudo-first-order reaction rate constant of TMP removal by 6.6-38.4 times and the mineralization rate by 36.5%-59.9%. The excellent performance might originate from the synergistic effect of VUV and Fe2+, i.e., VUV irradiation could effectively split water and largely accelerate the Fe3+/Fe2+ cycle to generate more reactive oxygen species (ROS). EPR results indicated that •OH and O2•- were identified as the main ROS in the UVC/Fe2+ and VUV/Fe2+ processes, while •OH, O2•-, and 1O2 were involved in the VUV process. The operating parameters, such as Fe2+ dosage and initial TMP contents, were evaluated and optimized. Up to 8 aromatic intermediates derived from hydroxylation, demethylation, carbonylation, and methylene group cleavage were identified by UPLC-QTOF-MS/MS technique, the possible pathways of TMP degradation were proposed. Finally, the acute and chronic toxicity of intermediates formed during TMP degradation in the VUV/Fe2+ process were also evaluated.


Asunto(s)
Fotólisis , Trimetoprim , Rayos Ultravioleta , Contaminantes Químicos del Agua , Trimetoprim/química , Trimetoprim/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Cinética , Antibacterianos/química , Antibacterianos/toxicidad , Hierro/química , Vacio , Catálisis , Animales
4.
Appl Microbiol Biotechnol ; 108(1): 359, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38836885

RESUMEN

Vacuum foam drying (VFD) has been shown to improve the thermostability and long-term shelf life of Newcastle Disease Virus (NDV). This study optimized the VFD process to improve the shelf life of NDV at laboratory-scale and then tested the optimized conditions at pilot-scale. The optimal NDV to T5 formulation ratio was determined to be 1:1 or 3:2. Using the 1:1 virus to formulation ratio, the optimal filling volumes were determined to be 13-17% of the vial capacity. The optimized VFD process conditions were determined to be at a shelf temperature of 25℃ with a minimum overall drying time of 44 h. The vaccine samples prepared using these optimized conditions at laboratory-scale exhibited virus titer losses of ≤ 1.0 log10 with residual moisture content (RMC) below 3%. Furthermore, these samples were transported for 97 days around China at ambient temperature without significant titer loss, thus demonstrating the thermostability of the NDV-VFD vaccine. Pilot-scale testing of the NDV-VFD vaccine at optimized conditions showed promising results for up-scaling the process as the RMC was below 3%. However, the virus titer loss was slightly above 1.0 log10 (approximately 1.1 log10). Therefore, the NDV-VFD process requires further optimization at pilot scale to obtain a titer loss of ≤ 1.0 log10. Results from this study provide important guidance for possible industrialization of NDV-VFD vaccine in the future. KEY POINTS: • The process optimization and scale-up test of thermostable NDV vaccine prepared through VFD is reported for the first time in this study. • The live attenuated NDV-VFD vaccine maintained thermostability for 97 days during long distance transportation in summer without cold chain conditions. • The optimized NDV-VFD vaccine preparations evaluated at pilot-scale maintained acceptable levels of infectivity after preservation at 37℃ for 90 days, which demonstrated the feasibility of the vaccine for industrialization.


Asunto(s)
Enfermedad de Newcastle , Virus de la Enfermedad de Newcastle , Temperatura , Vacunas Virales , Virus de la Enfermedad de Newcastle/inmunología , Virus de la Enfermedad de Newcastle/química , Proyectos Piloto , Enfermedad de Newcastle/prevención & control , Enfermedad de Newcastle/virología , Vacunas Virales/química , Vacunas Virales/inmunología , Vacio , Animales , Pollos , Desecación , China , Estabilidad de Medicamentos , Carga Viral
5.
Langenbecks Arch Surg ; 409(1): 86, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441680

RESUMEN

PURPOSE: Endoluminal vacuum sponge therapy has dramatically improved the treatment of anastomotic leaks in esophageal surgery. However, the blind insertion of vacuum sponge kits like Eso-Sponge® via an overtube and a pusher can be technically difficult. METHODS: We therefore insert our sponges under direct visual control by a nonstandard "piggyback" technique that was initially developed for the self-made sponge systems preceding these commercially available kits. RESULTS: Using this technique, we inserted or changed 56 Eso-Sponges® in seven patients between 2018 and 2023. Apart from one secondary sponge dislocation, no intraprocedural complications were encountered. One patient died due to unrelated reasons. In all others, the defects healed and they were dismissed from the hospital. Long-term follow-up showed three strictures that were successfully treated by dilatation. CONCLUSION: We conclude that sponge placement via piggyback technique is a fast, safe, and successful alternative to the standard method of insertion.


Asunto(s)
Fuga Anastomótica , Humanos , Fuga Anastomótica/cirugía , Vacio , Constricción Patológica
6.
Skin Res Technol ; 30(4): e13687, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38566505

RESUMEN

BACKGROUND: The physical appearance of an individual plays a primary role as it influences the opinion of the viewer. For this reason, orthodontic therapy to improve perceived aesthetics is in high demand among patients. This factor, combined with the increase in the number of non-invasive facial aesthetic treatments, has led to the need to understand potential risk factors in the application of medical devices to the perioral skin in patients with fixed orthodontic appliances. The aim of this study was to evaluate in vitro heating of the orthodontic bracket following electromagnetic fields and negative pressure (V-EMF) used as an anti-aging treatment. METHODS: Two different types of titanium alloy wires, one made of "beta-Titanium" alloy and the other "Ni-Ti" (DW Lingual Systems GmbH-Bad Essen-Germany) were used. The orthodontic wires and brackets mounted on a resin mouth were covered with porcine muscle tissue, then subjected to anti-aging therapy with a Bi-one LifeTouchTherapy medical device (Expo Italia Srl-Florence-Italy) which generates a combination of vacuum and electromagnetic fields (V-EMF) already adopted for antiaging therapy. During administration of the therapy, the orthodontic brackets and porcine tissue were thermally monitored using a Wavetek Materman TMD90 thermal probe (Willtek Communications GmbH-Germany). In total 20 orthodontic mouths were used, 10 with Beta Titanium wires and 10 with Nickel Titanium wires. RESULTS: A temperature increase of about 1°C was recorded in each group. The outcome of the present research shows that the absolute temperatures measured on orthodontic appliances, which, despite having a slightly different curve, both show an increase in temperature of 1.1°C at the end of the session, thus falling well within the safety range of 2°C as specified by the standard CENELEC EN 45502-1. Therefore, V-EMF therapy can be considered safe for the entire dental system and for metal prostheses, which tend to heat up at most as much as biological tissue (+0.9°C/1.1°C vs. 1.1°C/1.1°C). CONCLUSION: In conclusion, anti-aging therapy with V-EMF causes a thermal increase on orthodontic brackets that is not harmful to pulp health.


Asunto(s)
Campos Electromagnéticos , Níquel , Titanio , Humanos , Animales , Porcinos , Vacio , Calefacción , Alambres para Ortodoncia , Aleaciones , Ensayo de Materiales
7.
BMC Pediatr ; 24(1): 173, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461230

RESUMEN

BACKGROUND: Pectus excavatum, the most common chest wall deformity, is frequently treated with Nuss procedure. Here we will describe non-invasive procedure and analyze the variables associated vacuum bell therapy for patients with pectus excavatum. METHODS: Retrospective case-control study in a single center between July 2018 and February 2022, including patients with pectus excavatum treated with vacuum bell. Follow-up was continued to September 2022. The Haller index and Correction index was calculated before and after treatment to analysis the effectiveness of vacuum bell therapy. RESULTS: There were 98 patients enrolled in the treatment group, with 72 available for analysis, and the follow-up period ranged from 1.1 to 4.4 years (mean 3.3 years). When analyzing with the Haller Index, 18 patients (25.0%) showed excellent correction, 13 patients (18.1%) achieved good correction, and 4 patients (5.6%) had fair correction. The remaining patients had a poor outcome. Characteristics predicting a non-poor prognosis included initial age ≤ 11 years (OR = 3.94, p = 0.013) and patients with use over 24 consecutive months (OR = 3.95, p = 0.013). A total of 9 patients (12.5%) achieved a CI reduction below 10. Patients who started vacuum bell therapy at age > 11 had significantly less change compared to those who started at age ≤ 11 (P < 0.05). Complications included chest pain (5.6%), swollen skin (6.9%), chest tightness (1.4%) and erythema (15.3%). CONCLUSIONS: A certain percentage of patients with pectus excavatum can achieve excellent correction when treated with pectus excavatum therapy. Variables predicting better outcome including initial age ≤ 11 years both in HI and CI and vacuum bell use over 24 consecutive months in HI. In summary, pectus excavatum is an emerging non-invasive therapy for pectus excavatum and will be widely performed in a certain group of patients.


Asunto(s)
Tórax en Embudo , Pared Torácica , Humanos , Niño , Tórax en Embudo/terapia , Estudios Retrospectivos , Estudios de Casos y Controles , Vacio
8.
Childs Nerv Syst ; 40(4): 1213-1219, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38157046

RESUMEN

PURPOSE: The management of depressed skull fractures in infants can be either conservative or surgical. This study aimed to examine the outcomes of management with a negative-pressure vacuum device on depressed skull fractures in newborns. METHODS: Twenty-eight patients (aged 1-6 days) with simple depressed skull fractures underwent skull elevation using negative-pressure vacuum devices. A protocol for nonsurgical management was adopted for infants with such fractures between 2010 and 2023. All patients were initially evaluated with neurological examination and complementary assessments-hematological and coagulation studies, transfontanel transcranial ultrasound, skull radiography, and computed tomography scanning with three-dimensional reconstruction-according to availability and clinical needs. Gentle (negative) extraction pressure was applied with one of several devices (according to institutional availability) for a maximum duration of 60 s; this was performed as soon as possible after diagnosis, preferably within 72 h. Follow-up data, available in the clinical records, were reported. RESULTS: All patients exhibited satisfactory elevation of the depressed bone without associated injuries, except one patient who presented with an associated cephalohematoma which prevented optimal device coupling to generate sufficient vacuum pressure for correction. Neither neurological deficits nor development of epilepsy was noted; normal neurological assessment and oral alimentation tolerance were confirmed within 24 h post procedure. CONCLUSIONS: According to our data, ping-pong skull fracture elevation using the vacuum method is a safe and satisfactory treatment in the neonatal period. Early treatment allows for quick resolution, and in our opinion is the strategy of choice for depressed skull fractures in newborns.


Asunto(s)
Fractura Craneal Deprimida , Fracturas Craneales , Lactante , Humanos , Recién Nacido , Vacio , Cráneo , Cabeza
9.
Childs Nerv Syst ; 40(6): 1833-1838, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38411706

RESUMEN

PURPOSE: Depressed ("ping-pong") skull fractures can be treated by different means, including observation, non-surgical treatments, or surgical intervention. The authors describe their experience with vacuum-assisted elevation of ping-pong skull fractures and evaluate variables associated with surgical outcomes. METHODS: The authors present a retrospective review of all ping-pong skull fractures treated with vacuum-assisted elevation at the Children's Hospital of Orange County in 2021-2022. Variables included patient age, mechanism of injury, fracture depth, bone thickness at the fracture site, and degree of elevation. RESULTS: Seven patients underwent vacuum-assisted elevation of ping-pong fractures at the bedside without the use of anesthesia. Fractures caused by birth-related trauma were deeper than those caused by falls (p < 0.001). There was no significant difference between groups in bone thickness at the fracture site (2.10 mm vs 2.16 mm, n.s). Six of the seven patients experienced significant improvement in fracture site depression, with four displaying a complete fracture reduction and two displaying a significant reduction. The degree of fracture reduction was modestly related to the depth of fracture, with the two deepest fractures failing to achieve full reduction. Age appeared to be related to fracture reduction, with the lowest reduction observed in one of the oldest patients in this sample. No complications were observed in any patient other than temporary mild swelling at the suction site, and no re-treatment or surgery for the fractures was required. CONCLUSION: Vacuum-assisted elevation of ping-pong skull fractures is a safe and effective noninvasive treatment option for infants that can be used under certain circumstances. The procedure can be done safely at the bedside and is a relatively quick procedure. It avoids the need for open surgical intervention, anesthesia, or hospital admission, and can lead to excellent outcomes.


Asunto(s)
Fractura Craneal Deprimida , Humanos , Masculino , Femenino , Estudios Retrospectivos , Lactante , Preescolar , Fractura Craneal Deprimida/cirugía , Fractura Craneal Deprimida/diagnóstico por imagen , Niño , Vacio , Resultado del Tratamiento
10.
Orthod Craniofac Res ; 27(3): 485-493, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38226739

RESUMEN

OBJECTIVE: To compare the clinical effectiveness of V-bend bonded retainers (BR) versus vacuum-formed retainers (VFR) regarding their capacity to maintain treatment stability and survival rates after 12 months. MATERIALS AND METHODS: Patients finishing orthodontic treatment were randomly allocated into two groups. The BR group received maxillary and mandibular BRs in the lingual surfaces of the anterior teeth. The VFR group received VFRs right after fixed appliances removal. The patients were evaluated at four time-points: at fixed appliances removal (T0), after 3 (T1), 6 (T2) and 12 months (T3). In each time-point digital models were obtained and analysed with the OrthoAnalyzer™ software. Treatment stability based on occlusal outcomes and retainers' survival rates were evaluated. Intergroup comparisons were performed using Mann-Whitney U-tests. The Kaplan-Meier survival plot and the log-rank test were employed to assess the retainers' survival. RESULTS: Both BR and VFR groups included 25 patients. The groups were comparable regarding their baseline characteristics. Up to 6 months, both retainers were equally effective; however, after 12 months, BRs were more effective in maintaining the incisors' alignment in the maxilla and the mandible compared to the VFRs. No differences were noticed in the intercanine and intermolar widths, overjet and overbite. There were no differences regarding the retainers' survivability in both arches. CONCLUSIONS: BRs were more effective in maintaining the alignment of the incisors in the maxilla and mandible compared to VFRs after 12 months. Both retainers presented the same survival rates after the same period.


Asunto(s)
Diseño de Aparato Ortodóncico , Retenedores Ortodóncicos , Humanos , Femenino , Masculino , Vacio , Adolescente , Recubrimiento Dental Adhesivo/métodos , Resultado del Tratamiento , Maloclusión/terapia , Adulto Joven , Incisivo
11.
Eur Spine J ; 33(5): 2014-2021, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38416194

RESUMEN

PURPOSE: Intra-Discal Vacuum phenomenon (IDVP) is well-recognised, yet poorly visualised and poorly understood radiological finding in disc degeneration, particularly with regard to its role in spinal alignment. CT analysis of the lumbar spine in an aging population aims to identify patterns associated with IDVP including lumbopelvic morphology and associated spinal diagnoses. METHODS: An analysis was performed of an over-60s population sample of 2020 unrelated abdominal CT scans, without acute spinal presentations. Spinal analysis included sagittal lumbopelvic reconstructions to assess for IDVP and pelvic incidence (PI). Subjects with degenerative pathologies, including previous vertebral fractures, auto-fusion, transitional vertebrae, and listhesis, were also selected out and analysed separately. RESULTS: The prevalence of lumbar spine IDVP was 50.3% (955/1898) and increased with age (125 exclusions). This increased in severity towards the lumbosacral junction (L1L2 8.3%, L2L3 10.9%, L3L4 11.5%, L4L5 23.9%, and L5S1 46.3%). A lower PI yielded a higher incidence of IDVP, particularly at L5S1 (p < 0.01). A total of 292 patients had IDVP with additional degenerative pathologies, which were more likely to occur at the level of isthmic spondylolisthesis, adjacent to a previous fracture or suprajacent to a lumbosacral transitional vertebra (p < 0.05). CONCLUSIONS: This study identified the prevalence and severity of IDVP in an aging population. Sagittal patterns that influence the pattern of IVDP, such as pelvic incidence and degenerative pathologies, provide novel insights into the function of aging spines.


Asunto(s)
Degeneración del Disco Intervertebral , Vértebras Lumbares , Humanos , Vértebras Lumbares/diagnóstico por imagen , Anciano , Masculino , Femenino , Degeneración del Disco Intervertebral/epidemiología , Degeneración del Disco Intervertebral/diagnóstico por imagen , Persona de Mediana Edad , Anciano de 80 o más Años , Envejecimiento/patología , Envejecimiento/fisiología , Vacio , Tomografía Computarizada por Rayos X , Prevalencia
12.
Eur Spine J ; 33(3): 1013-1020, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38267734

RESUMEN

PURPOSE: Intervertebral vacuum phenomenon (IVP) and paraspinal muscular atrophy are age-related changes in the lumbar spine. The relationship between both parameters has not been investigated. We aimed to analyze the correlation between IVP and paraspinal muscular atrophy in addition to describing the lumbar vacuum severity (LVS) scale, a new parameter to estimate lumbar degeneration. METHODS: We analyzed patients undergoing spine surgery between 2014 and 2016. IVP severity was assessed utilizing CT scans. The combination of vacuum severity on each lumbar level was used to define the LVS scale, which was classified into mild, moderate and severe. MRIs were used to evaluate paraspinal muscular fatty infiltration of the multifidus and erector spinae. The association of fatty infiltration with the severity of IVP at each lumbar level was assessed with a univariable and multivariable ordinal regression model. RESULTS: Two hundred and sixty-seven patients were included in our study (128 females and 139 males) with a mean age of 62.6 years (55.1-71.2). Multivariate analysis adjusted for age, BMI and sex showed positive correlations between LVS-scale severity and fatty infiltration in the multifidus and erector spinae, whereas no correlation was observed in the psoas muscle. CONCLUSION: IVP severity is positively correlated with paraspinal muscular fatty infiltration. This correlation was stronger for the multifidus than the erector spinae. No correlations were observed in the psoas muscle. The lumbar vacuum severity scale was significantly correlated with advanced disc degeneration with vacuum phenomenon.


Asunto(s)
Degeneración del Disco Intervertebral , Músculos Paraespinales , Masculino , Femenino , Humanos , Persona de Mediana Edad , Músculos Paraespinales/diagnóstico por imagen , Músculos Paraespinales/patología , Vacio , Atrofia Muscular/diagnóstico por imagen , Atrofia Muscular/etiología , Atrofia Muscular/patología , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/patología , Imagen por Resonancia Magnética , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Vértebras Lumbares/patología
13.
Food Microbiol ; 119: 104448, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38225050

RESUMEN

We aimed to evaluate the bacterial growth and diversity in vacuum-packed beef bags stored at different temperatures and to monitor blown-pack spoilage. We used culture-based methods and high-throughput sequencing to study the development of the main bacterial groups naturally present in beef stored at 4 and 15 °C for 28 days. The growth of sulfite-reducing clostridium (SRC) was impaired in beef bags stored at 4 °C; significant differences among SRC counts were observed in beef bags stored at 4 and 15 °C on days 14, 21, and 28 (P = 0.001). Blown pack was observed in most beef bags stored at 15 °C, from day 14 to day 28, but not in beef bags stored at 4 °C. A storage temperature of 4 °C was able to maintain a stable bacterial microbiota (most prevalent: Photobacterium, Hafnia-Obesumbacterium, and Lactococcus). Remarkable changes in microbial abundance occurred at 15 °C from day 14 to day 28, with a predominance of strict anaerobes (Bacteroides) and the presence of Clostridium spp. The relative frequencies of strict anaerobes and Clostridium were statistically higher in the beef bags stored at 15 °C (P < 0.001 and P = 0.004, respectively). The temperature influenced the microbial counts and relative abundance of spoilage bacteria, leading to blown pack spoilage.


Asunto(s)
Embalaje de Alimentos , Microbiota , Animales , Bovinos , Embalaje de Alimentos/métodos , Carne/microbiología , Temperatura , Vacio , Bacterias/genética , Clostridium , Microbiología de Alimentos
14.
J Dairy Sci ; 107(3): 1778-1787, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37806627

RESUMEN

We investigated the suitability of the quarter mouthpiece chamber vacuum (MPCV) as an indicator for cessation of quarter milk flow to potentially adjust the teat end vacuum at a quarter level. We tested the hypothesis that a MPCV increase is a clear indicator of quarter milk flow cessation. In addition, we tested if a quarter-individual vacuum reduction at MPCV increase reduces the mechanical effect on the teat. Ten dairy cows were milked twice daily with a quarter-specific vacuum supply with continuously high (51 kPa; TRT51) or low vacuum setting (41 kPa; TRT41), or high vacuum setting combined with a quarter-specific vacuum reduction by 10 kPa immediately after the quarter-specific MPCV increase (TRT51/41). Whole udder milk flow was continuously recorded. Each treatment was repeated at 4 subsequent milkings. The high vacuum settings (TRT51; TRT51/41) reached higher values in peak flow rate and average milk flow and consequently shorter machine-on time. The time from start of milking until the steep increase of the MPCV was shorter in front than rear quarters, and hence the time from start of MPCV increase until end of milking was longer in front than rear teats. Teat condition of the right front teats was measured for teat wall diameter by ultrasound and teat tissue thickness by cutimeter at 5 and 20 min after each experimental milking. The teat measurements were taken at the teat tip (distal barrel) and 2 cm above the teat tip (proximal barrel). The proximal teat wall diameter tended to be higher in TRT51 than in TRT41, both 5 and 20 min after milking. The distal teat wall diameter at 5 min was greater in TRT51 than in TRT41. In TRT51/41 the teat wall diameter at both locations was intermediate, not significantly different from either TRT51 or TRT41. The distal teat tissue thickness was greater in TRT51 than in TRT41, and tended to be greater in TRT51/41 than in TRT41 at 5 min. The proximal teat tissue thickness at 5 min was higher in TRT51 and TRT51/41 than in TRT41. The teat tissue thickness decreased from 5 to 20 min only in the proximal barrel. The quarter-individual MPCV increase appears to be a suitable indicator of the cessation of milk flow. The lack of a significant reduction of mechanical effect on the teat by a reduced vacuum of 41 kPa indicates that the vacuum level chosen may be still too high under conditions of a separate vacuum supply for each quarter, which prevents a vacuum drop caused by the whole udder milk flow.


Asunto(s)
Glándulas Mamarias Animales , Leche , Animales , Bovinos , Femenino , Vacio , Extremidad Inferior , Pezones
15.
J Dairy Sci ; 107(2): 774-789, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37769946

RESUMEN

Traditional ways to preserve cream involve processing it into butter, butter oil, or frozen storage. These technologies do not preserve the unique functionality of cream with respect to whipping or processing into butter. In this work, microwave vacuum drying (MVD) was investigated as a method to manufacture dehydrated cream. Dehydrated cream microstructure, color, and free fat were evaluated using scanning electron microscopy, colorimetry, and solvent extraction, respectively. Effects of homogenization on reconstituted cream microstructure and functionality were investigated using confocal laser scanning microscopy, color, particle sizing, and texture analysis of whipped cream. Reconstituted MVD cream whipped faster, and the whipped cream was more cohesive and firmer when 2-step homogenization at 3.5/7 MPa was used. Fat globules in reconstituted MVD cream were covered by phospholipids, explaining MVD cream's similar functionality compared with pasteurized cream. These results may foster the development of novel shelf stable and highly functional dairy products using MVD.


Asunto(s)
Productos Lácteos , Microondas , Animales , Vacio , Productos Lácteos/análisis , Mantequilla/análisis
16.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38474897

RESUMEN

On-farm milk flow meter technology facilitates real-time assessment of individual cow milking observations and could be used to detect milking liner slips during machine milking of dairy cows. Here, we compared the accuracy of on-farm milk flow meters for detecting milking liner slips with that of audible detection and that of a portable vacuum recording system. Compared to audible detection methods, the on-farm milk flow meter facilitated the detection of milking liner slips with moderate accuracy. Using the vacuum recording system as the gold standard, the milk flow meter system failed to detect most of the liner slips, leading to poor agreement between the two devices. We conclude that the on-farm milk flow meter system tested here compared well with audible detection; however, when vacuum recordings were considered, we found significant levels of under-detection. Taken together, dairy operators may use the on-farm milk flow meter system to inform adjustments of the milking machine settings and monitor milking routine performance. However, the system is not suitable for monitoring short-duration vacuum fluctuations. Future research is warranted to optimize the sensor-based detection of milking liner slips.


Asunto(s)
Lactancia , Leche , Animales , Femenino , Bovinos , Industria Lechera/métodos , Glándulas Mamarias Animales , Vacio
17.
J Orthop Sci ; 29(2): 472-479, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36697335

RESUMEN

INTRODUCTION: Preoperative difference in lumbar lordosis (DiLL) was associated with surgical outcomes after single-level transforaminal lumbar interbody fusion (TLIF). Patients with DiLL>0 (DiLL (+)) tended to show worse clinical outcomes and postoperative greater restoration of lumbar lordosis (LL). However, some patients with DiLL (+) showed relatively good outcomes and no postoperative LL restration. This study aimed to elucidate whether the lumbar intervertebral disc vacuum phenomenon (VP) influences clinical course after single-level TLIF in patients with DiLL (+) and DiLL (-). METHODS: Patients with lumbar spinal stenosis and degenerative spondylolisthesis treated with single-level TLIF were included. Pre- and postoperative LL were measured, and postoperative LL improvement was calculated. Preoperative DiLL was calculated as preoperative supine LL minus standing LL. Severity of VP at the non-fused discs (SVP (non-FS)) was evaluated using preoperative reconstructed computed tomography imaging. Clinical outcomes were assessed using the Oswestry disability index, visual analogue scale (VAS; low back pain (LBP), lower-extremity pain, numbness, and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Patients were stratified by the median preoperative SVP (non-FS) score into severe and mild VP groups in patients with DiLL (+) or DiLL (-), and their surgical outcomes were compared. RESULTS: Overall, 89 patients were included. In patients with DiLL (+) (n = 37), patients with severe VP showed worse clinical outcomes, particulary for LBP and DiLL (+) patients with mild VP showed greater LL improvement (6.5° ± 10.0°). In patients with DiLL(-) (n = 52), patients with severe VP showed worse clinical outcomes, particularly for LBP and no differences in preoperative, postoperative, and improvement of LL were observed between two groups. CONCLUSION: Patients with DiLL (+) and DiLL (-) showed different clinical courses depending on VP severity at the non-fused discs after single-level TLIF.


Asunto(s)
Lordosis , Dolor de la Región Lumbar , Fusión Vertebral , Espondilolistesis , Humanos , Lordosis/diagnóstico por imagen , Lordosis/cirugía , Fusión Vertebral/métodos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Vacio , Dolor de Espalda/etiología , Dolor de la Región Lumbar/cirugía , Dolor de la Región Lumbar/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/cirugía , Espondilolistesis/complicaciones
18.
Radiol Med ; 129(5): 767-775, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38512628

RESUMEN

PURPOSE: Breast magnetic resonance imaging (MRI) can detect some malignant lesions that are not visible on mammography (MX) or ultrasound (US). If a targeted, second-look fails, MRI-guided breast biopsy is the only available tool to obtain a tissue sample and pathological proof of these "MRI-only lesions". The aim of this study is to report the performance and underestimation rate of 9G MRI-guided vacuum-assisted breast biopsy (VABB) over 12 years at a single center. MATERIAL AND METHODS: All 9G MRI-VABB procedures performed from January 2010 to December 2021 were retrospectively reviewed. Two MRI scanners (1.5 T and 3 T) were used with the same image resolution and contrast media. All suspicious lesions detected only by breast MRI underwent biopsy. Reference standard was histological diagnosis or at least 1-year negative follow-up. All malignant and atypical lesions underwent surgery, which was used as the reference standard. RESULTS: A total of 293 biopsies were retrospectively reviewed. Histopathological VABB results revealed 142/293 (48.4%) benign lesions, 77/293 (26.2%) high-risk lesions, and 74/293 (25.2%) malignant lesions. No significant complications were observed. Surgical pathology results allowed for the reclassification of n = 7/48 B3b lesions: n = 4 were ductal carcinoma in situ, while n = 3 presented invasive features at surgical histology (2 IDC; 1 ILC). B3b underestimation occurred overall in 14.6% of B3 cases. Breast follow-up was achieved for all benign VABB results, and only one false-negative case was observed. CONCLUSION: Our results confirm that 1.5 T and 3 T MRI-guided VABB is an accurate and safe procedure for histopathologic final diagnosis of MRI-only lesions. Critical issues remain the potential high-risk underestimation rate of B3b VABB results and management of follow-up of benign lesions.


Asunto(s)
Neoplasias de la Mama , Biopsia Guiada por Imagen , Humanos , Femenino , Estudios Retrospectivos , Neoplasias de la Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Persona de Mediana Edad , Biopsia Guiada por Imagen/métodos , Adulto , Vacio , Anciano , Mama/diagnóstico por imagen , Mama/patología , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética Intervencional/métodos , Anciano de 80 o más Años
19.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38612506

RESUMEN

Positronium (Ps) is a valuable probe to investigate nanometric or sub-nanometric cavities in non-metallic materials, where Ps can be confined. Accessible experimental measurements concern the lifetime of trapped Ps, which is largely influenced by pick-off processes, depending on the size of the cavity as well as on the density of the electrons belonging to the surface of the host trap. Another relevant physical quantity is the contact density, that is the electron density at the positron position, which is usually found to be well below the vacuum value. Here, we review the principal models that have been formulated to account and explain for these physical properties of confined Ps. Starting with models, treating Ps as a single particle formulated essentially to study pick-off, we go on to describe more refined two-particle models because a two-body model is the simplest approach able to describe any change in the contact density, observed in many materials. Finally, we consider a theory of Ps annihilation in nanometric voids in which the exchange correlations between the electron of Ps and the outer electrons play a fundamental role. This theory is not usually taken into account in the literature, but it has to be considered for a correct theory of pick-off annihilation processes.


Asunto(s)
Nanoporos , Ligando de CD40 , Electrones , Vacio
20.
J Environ Manage ; 351: 119785, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38081086

RESUMEN

Membrane fouling induced by natural organic matter (NOM) has seriously affected the further extensive application of ultrafiltration (UF). Herein, a simple, green and robust vacuum ultraviolet (VUV) technology was adopted as pretreatment before UF and ultraviolet (UV) technology was used for comparison. The results showed that control effect of VUV pretreatment on membrane fouling was better than that of UV pretreatment, as evidenced by the increase of normalized flux from 0.27 to 0.38 and 0.73 after 30 min UV or VUV pretreatment, respectively. This is related to the fact that VUV pretreatment exhibited stronger NOM degradation ability than UV pretreatment owing to the formation of HO•. The steady-state concentration of HO• was calculated as 3.04 × 10-13 M and the cumulative exposure of HO• reached 5.52 × 10-10 M s after 30 min of VUV irradiation. And the second-order rate constant between NOM and HO• was determined as 1.36 × 104 L mg-1 s-1. Furthermore, fluorescence EEM could be applied to predict membrane fouling induced by humic-enriched water. Standard blocking and cake filtration were major fouling mechanisms. Moreover, extension of UV pretreatment time increased the disinfection by-products (DBPs) formation, the DBPs concentration was enhanced from 322.36 to 1187.80 µg/L after 210 min pretreatment. However, VUV pretreatment for 150 min reduced DBPs content to 282.57 µg/L, and DBPs content continued to decrease with the extension of pretreatment time, revealing that VUV pretreatment achieved effective control of DBPs. The variation trend of cytotoxicity and health risk of DBPs was similar to that of DBPs concentration. In summary, VUV pretreatment exhibited excellent effect on membrane fouling alleviation, NOM degradation and DBPs control under a certain pretreatment time.


Asunto(s)
Desinfección , Purificación del Agua , Purificación del Agua/métodos , Ultrafiltración/métodos , Vacio , Rayos Ultravioleta , Membranas Artificiales
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