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1.
Eur J Oral Sci ; 132(2): e12977, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369878

RESUMO

Although dry mouth is a relatively common condition, salivary flow is not routinely measured in dental clinical practice. Moreover, existing data regarding the use of the modified Schirmer test (MST) for the screening of dry mouth has not been summarized. This systematic review and meta-analysis, conducted in accordance with the PRISMA guidelines, aimed to determine whether the modified Schirmer test can be used to identify dry mouth. The databases of PubMed, Scopus, ScienceDirect, and CENTRAL (CRD42023393843) were systematically searched to retrieve articles published until 9th November 2023. Among the 343 original articles retrieved, six met the inclusion criteria. A total of 1150 patients, comprising 710 (61.7%) women and 440 (38.3%) men (mean age, 47.1 ± 7.3 years), were included. The meta-analysis revealed a weak correlation coefficient of r ¯ $\bar{r}$  = 0.42 (95% Cl: 0.29-0.55) between MST and the unstimulated salivary flow rate. Therefore, while the MST might offer a simple and accessible alternative for initial screening in the future, especially in non-specialized settings, its variability in sensitivity and specificity, along with an actual lack of standardization, necessitates cautious interpretation. Further studies are necessary before recommending the test in clinical routine.


Assuntos
Xerostomia , Humanos , Xerostomia/diagnóstico , Xerostomia/fisiopatologia , Saliva/química , Glândulas Salivares/fisiopatologia , Salivação/fisiologia , Feminino , Sensibilidade e Especificidade
2.
Electrophoresis ; 41(10-11): 852-859, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31054174

RESUMO

The pressure-driven device is designed and the flow rates of the microfluidic systems can be supplied by the pressure-driven flows, which can significantly reduce the flow-rate fluctuations coming from the pump source. For pressure-driven flows, the flow rates of the fluids can be predicted by measuring the pressure drop along a polytetrafluoroethylene (PTFE) tubing. Especially, by varying the geometrical parameters of the PTFE tubing, the predicted flow rates of the fluids are compared with the experimental measurements, and the testing precision of the pressure-driven flows can be obtained. Meanwhile, the dynamic characteristics of the open-loop and closed-loop control pressure-driven device are comparatively studied. Particularly, a proportional and integral (PI) controller is integrated with the closed-loop control pressure-driven device, and the effects of the parameters of the PI controller on the dynamic characteristics of the pressure-driven devices are mainly discussed. Most importantly, by improving the dynamic characteristics of the pressure-driven devices, precise measurement and control of the pressure-driven flows can be achieved for microfluidic systems.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Desenho de Equipamento , Pressão , Viscosidade
3.
Clin Oral Investig ; 24(11): 4123-4131, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32436164

RESUMO

OBJECTIVES: The aim of this study was to analyze the influence of dietary fatty acids (FAs) and the time elapsed from their intake on FA tissue profile of rat submandibular gland (SG) and on its salivary flow rate (SFR). Do dietary FAs depending on the intake time modify their profile in SG and consequently the SFR? MATERIALS AND METHODS: Thirty-six adult male Wistar rats were fed on control diet (corn oil, CD, 18:2 n-6 FA) for 7 days and then divided into CD and two groups with replacement of corn oil by olive (OD, 18:1 n-9 FA) or chia (ChD, 18:3 n-3 FA) oils (1 and 30 day intake). Submandibular ducts were canalized to collect saliva for 20 min (µL/min). SG were examined (optical/electron microscopy; ImageJ 1.48 software). RESULTS: SFR values were 6.18 ± 0.34 (CD1), 6.04 ± 0.31 (OD1), and 6.00 ± 0.50 (ChD1) (p > 0.05). At 30-day intake, higher SFR values in ChD (7.82 ± 0.7) with respect to CD (4.68 ± 0.44; p < 0.001) and OD (6.08 ± 0.2; p = 0.038) were found. ChD30 showed a higher serous acinous area percentage than CD30 and OD30, whereas mucous acinous density was greater in CD30 than in OD30 and ChD30 (p < 0.05). α-Linolenic (ALA) and eicosapentaenoic and docosahexaenoic acid levels were only detected in SG of ChD30, while arachidonic acid was lower in this group as compared with CD30 and OD30 (p < 0.05). CONCLUSIONS: SG FA composition and its SFR appear to be modulated by dietary FAs and the time elapsed from their consumption. SFR is highest with n-3 ALA-rich ChD at 30-day intake. CLINICAL RELEVANCE: Diet could contribute to improve secretory dysfunctions.


Assuntos
Ácidos Graxos Ômega-3 , Glândula Submandibular , Animais , Dieta , Ácidos Graxos , Masculino , Óleos de Plantas , Ratos , Ratos Wistar
4.
Artigo em Inglês | MEDLINE | ID: mdl-32432966

RESUMO

In this study, a newly developed liquid-phase plasma discharge (LPPD) process was evaluated for removing methylene blue (MB) in water. Three independent variables, i.e., liquid flow rate (LF), air flow rate (AF), and MB concentration in water, were all tested at five levels (37, 68, 81, 94, and 103 mL/min for LF; 1, 2, 3, 4, and 5 L/min for AF; and 10, 30, 50, 70, and 90 mg/L for MB) using Central Composite Design (CCD) and Response Surface Methodology (RSM) to optimize the operation for the plasma reactor. The results showed that the regression model produced by the CCD/RSM analysis could adequately predict the MB removal rate of the LPPD process with a model p value of less than 0.0001. The uncertainty analysis further confirmed the error range for the regression model was from -3.93% to 0.63% in predicting the MB removal rate within the ranges of the three independent variables tested. The removal rates were all above *Address correspondence to Dr. Sarah Wu, Department of Biological Engineering, University of Idaho, 875 Perimeter Drive MS 0904, Moscow, ID 83844-0904. 99% for the MB concentrations experimented at LF 68 mL/min and AF 4 L/min. The results concluded that the novel LPPD process was effective in removing MB from dye wastewater.


Assuntos
Técnicas Eletroquímicas/métodos , Azul de Metileno/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Modelos Teóricos , Gases em Plasma/química
5.
Crit Care ; 23(1): 395, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806045

RESUMO

BACKGROUND: Expiratory flow limitation (EFL) is characterised by a markedly reduced expiratory flow insensitive to the expiratory driving pressure. The presence of EFL can influence the respiratory and cardiovascular function and damage the small airways; its occurrence has been demonstrated in different diseases, such as COPD, asthma, obesity, cardiac failure, ARDS, and cystic fibrosis. Our aim was to evaluate the prevalence of EFL in patients requiring mechanical ventilation for acute respiratory failure and to determine the main clinical characteristics, the risk factors and clinical outcome associated with the presence of EFL. METHODS: Patients admitted to the intensive care unit (ICU) with an expected length of mechanical ventilation of 72 h were enrolled in this prospective, observational study. Patients were evaluated, within 24 h from ICU admission and for at least 72 h, in terms of respiratory mechanics, presence of EFL through the PEEP test, daily fluid balance and followed for outcome measurements. RESULTS: Among the 121 patients enrolled, 37 (31%) exhibited EFL upon admission. Flow-limited patients had higher BMI, history of pulmonary or heart disease, worse respiratory dyspnoea score, higher intrinsic positive end-expiratory pressure, flow and additional resistance. Over the course of the initial 72 h of mechanical ventilation, additional 21 patients (17%) developed EFL. New onset EFL was associated with a more positive cumulative fluid balance at day 3 (103.3 ml/kg) compared to that of patients without EFL (65.8 ml/kg). Flow-limited patients had longer duration of mechanical ventilation, longer ICU length of stay and higher in-ICU mortality. CONCLUSIONS: EFL is common among ICU patients and correlates with adverse outcomes. The major determinant for developing EFL in patients during the first 3 days of their ICU stay is a positive fluid balance. Further studies are needed to assess if a restrictive fluid therapy might be associated with a lower incidence of EFL.


Assuntos
Ventilação Pulmonar/fisiologia , Insuficiência Respiratória/etiologia , Adulto , Asma/complicações , Asma/fisiopatologia , Cuidados Críticos/métodos , Cuidados Críticos/tendências , Fibrose Cística/complicações , Fibrose Cística/fisiopatologia , Feminino , Humanos , Pulmão/anatomia & histologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Prevalência , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/fisiopatologia , Insuficiência Respiratória/fisiopatologia , Mecânica Respiratória/fisiologia , Fatores de Risco , Escore Fisiológico Agudo Simplificado
6.
Neurourol Urodyn ; 37(6): 1913-1924, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29664182

RESUMO

OBJECTIVE: Our hypothesis was to confirm whether an idealized voider flow equation (IVFE) that we created is more accurate than trying to rely on estimated flow rates in the same patient in two consecutive voids. We also looked to confirm whether flow index (FI) can be a proxy for voiding efficiency and to identify which FI was best; those based off our own IVFE equations or those derived from the commonly used power equations. STUDY DESIGN: We used data from a previous study and calculated flow rates using our IVFE and the power equations. Descriptive statistics and non-parametric tests were performed along with error analysis using Bland Altman (BA) and accuracy analysis (AA). RESULTS: Bland Altman (BA) analysis revealed that flows obtained from normal voiders voiding between 100 and 200 cc as well as from 50 cc to 115% of EBC are comparable and tend to be reproducible in subsequent voids. FI derived from the IVFE exhibit less bias than Qmax making it a better way to compare these voids. A comparison of Qmax and flow index for different combinations of volumes and PVR's was done utilizing BA and accuracy measures both indicating that FI was more reproducible. CONCLUSION: The data support both of our hypothesis that flow index is a good measure of voiding efficiency. We have also shown that IVFE is a better and more accurate measure of calculating a flow index than the power equations regardless of the volume and PVR scenarios that are presented.


Assuntos
Algoritmos , Micção/fisiologia , Urodinâmica , Criança , Pré-Escolar , Correlação de Dados , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes
7.
Inhal Toxicol ; 30(11-12): 416-428, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30618352

RESUMO

Regional deposition of inhaled aerosols is essential for assessing health risks from toxic exposure. Upper airway physiology plays a significant role in respiratory defense by filtering micrometer particles, whose deposition mechanism is predominantly inertial impaction and is mainly controlled by airflow characteristics. The monkey is commonly used in tests that study inhalation toxicity as well as in preclinical tests as human surrogates due to their anatomical similarities to humans. Therefore, accurate predictions and an understanding of the inhaled particles and their distribution in monkeys are essential for extrapolating laboratory animal data to humans. The study goals were as follows: (1) to predict the particle deposition based on aerodynamic diameters (1-10 µm) and various steady inspiratory flow rates in computational models of monkey and human upper airways; and (2) to investigate potential differences in inhalation flow and particle deposition between humans and monkeys by comparing numerical simulation results with similar in-vitro and in-vivo measurements from recent literature. The deposition fractions of the monkey's numerical airway model agreed well with in-vitro and human model data when equivalent Stokes numbers were compared, based on the minimum cross-sectional area as representative of length scale. Vestibule removal efficiencies were predicted to be higher in the monkey model compared with the human model. Our results revealed that the particle transportations were sensitive to the anatomical structure, airway geometry, airflow rates, inflow boundary conditions and particle size.


Assuntos
Modelos Anatômicos , Modelos Biológicos , Material Particulado/farmacocinética , Sistema Respiratório/metabolismo , Administração por Inalação , Adulto , Aerossóis , Animais , Simulação por Computador , Humanos , Exposição por Inalação , Macaca fascicularis , Masculino , Tamanho da Partícula
8.
Am J Emerg Med ; 36(5): 739-740, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29079377

RESUMO

BACKGROUND: Poiseuille's law states flow rates are directly proportional to the radius to the 4th power and indirectly proportional to the length of a tube. Because of this property, large bore catheters are commonly used in the resuscitation of the critically ill patient. However, there are no studies comparing simultaneous use of all three lumens of a triple lumen (TL) central venous catheter (CVC) with other catheter types. Our objective was to compare the flow rates of normal saline (NS) through various resuscitation catheters against a TL CVC using all 3 ports. METHODS: We performed a blinded prospective observational study of flow rates utilizing multiple resuscitation catheters. Each catheter type was attached to a 1l bag of NS using standard saline tubing and mean time to infuse 1l of normal saline was determined. Three trials each were completed with and without pressure bags. RESULTS: Simultaneous infusion of NS through all ports of a TL CVC demonstrated no statistically significant difference compared to the following catheters: 16ga peripheral venous catheter (PVC) and 6 Fr CVC with pressure bag. The 14 g PVC and 8.5Fr CVC had statistically significant faster flow rates than the TL CVC both with and without a pressure bag. The 6Fr CVC showed significantly faster flow rates than the TL CVC without a pressure bag. CONCLUSIONS: Simultaneous use of all 3 ports of a TL CVC generates flow rates comparable to many other commonly used resuscitation catheters.


Assuntos
Cateterismo Venoso Central/instrumentação , Cateteres de Demora , Cateteres Venosos Centrais , Ressuscitação/normas , Estado Terminal , Desenho de Equipamento , Humanos , Bombas de Infusão , Teste de Materiais , Estudos Prospectivos , Método Simples-Cego
10.
Neurourol Urodyn ; 35(7): 836-46, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26175192

RESUMO

PURPOSE: We hypothesized that by correcting for volume and creating a flow index (FI) we could develop a reproducible and reliable means to estimate flows in children without the use of a flow nomogram. Our second hypothesis was that this volume corrected FI could define objective parameters for the different flow curves that are described in the ICCS document. METHODS: Uroflowmetry curves of 1,268 healthy children were analyzed. Quadratic equations using nonlinear regression for both sexes were generated for each set of presumed normal voiders (learning data) (NV). The NV test data were used to verify the equations. Linear regression analysis was used to compare the variance between actual and estimated flow rates. A FI (Actual Qavg/Estimated Qavg) was created and ROC analysis for all flow types was performed. Sensitivity and specificity analysis was performed on all voids to validate the accuracy of the FI to predict flow pattern. RESULTS: Analysis of the FI from the first void to the second confirmed the accuracy and reproducibility in both males and females using various means of analysis. ROC analysis shows that there are very strong AUC's for Bell, plateau, and tower flow patterns. Sensitivity and specificity analysis reveals that defined FI parameters are able to predict the flow patterns. CONCLUSION: Our predictive formulas allow for direct comparison of one flow to the next in a single patient when the FI is used. Utilizing the FI, we can predict the type of flow pattern removing subjectivity from the analysis of uroflow patterns. Neurourol. Urodynam. 35:836-846, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Micção/fisiologia , Urodinâmica/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Nomogramas , Valores de Referência , Reprodutibilidade dos Testes
11.
Biomed Eng Online ; 15(Suppl 2): 149, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-28155688

RESUMO

BACKGROUND: Mechanical load-induced intraosseous pressure gradients may result in some fluid stimuli effects, such as fluid flow and fluid shear stress (FSS), which may enable bone cells to detect external mechanical signals. Interstitial bone fluid flow is known to occur in lacunar-canalicular porosity (PLC). METHODS: In order to characterize lacunar-canalicular fluid flow behavior, a hierarchical osteon system is developed. The osteon is modeled as a poroelastic annular cylinder with two types of impermeable boundary cases considered on its outer wall: one is elastic restrained (Case I), whereas the other is displacement confined (Case II). Analytical solutions such as canalicular fluid velocity, pressure, fluid flow rate (FFR), and shear stress are obtained. RESULTS: Results show that the amplitudes of FFR and FSS are proportional to strain amplitude and frequency. However, the key loading factor governing canalicular fluid flow behavior is the strain rate. The larger canalicular radius is, the larger amplitudes of FFR and FSS generalized, especially, the FSS amplitude is proportional to canalicular radius. In addition, both FFR and FSS amplitudes produced in case II are larger than those of case I. CONCLUSION: Strain rate can be acted as a representative loading parameter governing the canalicular fluid flow behavior under a physiological state. This model can facilitate better understanding the load induced the fluid permeation in the PLC. The approach can also be used to analyze the structure of the proteoglycan matrix in the fluid space surrounding the osteocytic process in the canaliculus.


Assuntos
Osso e Ossos/fisiologia , Ósteon/fisiologia , Resistência ao Cisalhamento , Fenômenos Biomecânicos , Elasticidade , Humanos , Hidrodinâmica , Modelos Biológicos , Modelos Estatísticos , Porosidade , Reologia , Estresse Mecânico
12.
Bull Environ Contam Toxicol ; 96(6): 750-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27022936

RESUMO

Drainage systems are integral parts of agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental agricultural drainage ditches during a simulated summer runoff event. Study objectives were to examine the influence of routine mowing of vegetated ditches on nutrient mitigation and to assess spatial transformation of nutrients along ditch length. Both mowed and unmowed ditch treatments decreased NO3 (-)-N by 79 % and 94 % and PO4 (3-) by 95 % and 98 %, respectively, with no significant difference in reduction capacities between the two treatments. This suggests occasional ditch mowing as a management practice would not undermine nutrient mitigation capacity of vegetated drainage ditches.


Assuntos
Agricultura/métodos , Meio Ambiente
13.
J Surg Oncol ; 110(8): 970-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25171494

RESUMO

BACKGROUND/OBJECTIVES: Heated intraperitoneal chemotherapy (HIPEC) kills cancer cells via thermal injury and improved chemotherapeutic cytotoxicity. We hypothesize that higher HIPEC flow rates improve peritoneal heating and HIPEC efficacy. METHODS: (1) A HIPEC-model (30.8 L cooler with attached extracorporeal pump) was filled with 37°C water containing a suspended 1 L saline bag (SB) wrapped in a cooling sleeve, creating a constant heat sink. (2) HIPECs were performed in a swine model. Inflow, outflow, and peritoneal temperatures were monitored as flow rates varied. (3) Flow rates and temperatures during 20 HIPECs were reviewed. RESULTS: Higher flow rates decreased time required to increase water bath (WB) and SB temperature to 43°C. With a constant heat sink, the minimum flow rate required to reach 43°C in the WB was 1.75 L/min. Higher flow rates lead to greater temperature gradients between the WB and SB. In the swine model, the minimum flow rate required to reach 43°C outflow was 2.5-3.0 L/min. Higher flows led to more rapid heating of the peritoneum and greater peritoneal/outflow temperature gradients. Increased flow during clinical HIPEC suggested improved peritoneal heating with lower average visceral temperatures. CONCLUSIONS: There is a minimum flow rate required to reach goal temperature during HIPEC. Flow rate is an important variable in achieving and maintaining goal temperatures during HIPEC.


Assuntos
Antineoplásicos/administração & dosagem , Hipertermia Induzida/métodos , Neoplasias Peritoneais/terapia , Animais , Terapia Combinada , Humanos , Injeções Intraperitoneais , Suínos
14.
Saudi J Anaesth ; 18(3): 388-394, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149724

RESUMO

Introduction: In the backdrop of escalating healthcare costs and an increasing focus on resource optimization, this audit study delves into the realm of anesthesia management, specifically exploring the application of low-flow anesthesia (LFA). The primary objective was to assess adherence to hospital standards and evaluate the economic implications of LFA (<1 L/min). Materials and Methods: This retrospective audit focused on 700 adult patients undergoing elective surgeries with general anesthesia. Data sources included anesthesia records, electronic recording systems, and audits by a dedicated team. Fresh gas flow rates (FGFRs), minimum alveolar concentration (MAC), and volatile anesthetic consumption were analyzed. Cost comparisons between low-flow and high-flow anesthesia were conducted, employing specific cost per milliliter metrics. Results: The average FGFR during the maintenance phase was found to be 0.45 ± 0.88 L/min. Adherence to hospital standards was notably high, with 94.29% of patients being maintained on low-flow gas rates. The differences in anesthetic consumption between low-flow and high-flow FGFR were statistically significant for both desflurane (12.17 ± 10.84 ml/MAC hour versus 43.12 ± 27.25 ml/MAC hour) and sevoflurane (3.48 ± 7.22 ml/MAC hour versus 5.20 ± 5.20 ml/MAC hour, P < 0.001). The calculated savings per patient with low-flow desflurane and sevoflurane anesthesia compared to high flow were found to be 109.25 AED and 6.74 AED, respectively. Conclusion: This audit advocates for the widespread adoption of LFA as a standard practice. Beyond aligning with hospital standards, the study highlights the multi-faceted benefits of LFA, encompassing economic savings, environmental safety, and enhanced patient care.

15.
Crit Care Explor ; 6(4): e1065, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38533293

RESUMO

OBJECTIVES: In 2020, cefiderocol became the first Food and Drug Administration-approved medication with continuous renal replacement therapy (CRRT) dosing recommendations based on effluent flow rates (QE). We aimed to evaluate the magnitude and frequency of factors that may influence these recommendations, that is, QE intrapatient variability and residual renal function. DESIGN: Retrospective observational cohort study. SETTING: ICUs within Hartford Hospital (890-bed, acute-care hospital) in Connecticut from 2017 to 2023. PATIENTS: Adult ICU patients receiving CRRT for greater than 72 hours. MEASUREMENTS AND MAIN RESULTS: CRRT settings including QE and urine output (UOP) were extracted from the time of CRRT initiation (0 hr) and trends were assessed. To assess the impact on antibiotic dosing, cefiderocol doses were assigned to 0 hour, 24 hours, 48 hours, and 72 hours QE values per product label, and the proportion of antibiotic dose changes required as a result of changes in inpatient's QE was evaluated. Among the 380 ICU patients receiving CRRT for greater than 72 hours, the median (interquartile range) 0 hour QE was 2.96 (2.35-3.29) L/hr. Approximately 9 QE values were documented per patient per 24-hour window. QE changes of greater than 0.75 L/hr were observed in 21.6% of patients over the first 24 hours and in 7.9% (24-48 hr) and 5.8% (48-72 hr) of patients. Approximately 40% of patients had UOP greater than 500 mL at 24 hours post-CRRT initiation. Due to QE changes within 24 hours of CRRT initiation, a potential cefiderocol dose adjustment would have been warranted in 38% of patients (increase of 21.3%; decrease of 16.6%). QE changes were less common after 24 hours, warranting cefiderocol dose adjustments in less than 15% of patients. CONCLUSIONS: Results highlight the temporal and variable dynamics of QE and prevalence of residual renal function. Data also demonstrate a risk of antibiotic under-dosing in the first 24 hours of CRRT initiation due to increases in QE. For antibiotics with QE-based dosing recommendations, empiric dose escalation may be warranted in the first 24 hours of CRRT initiation.

16.
Environ Sci Pollut Res Int ; 30(2): 4603-4616, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35974272

RESUMO

The investment of solar energy in life applications has become mandatory to maintain a clean environment and reduce the use of fossil fuels. This work aimed to improve the performance of solar air heater (SAH) by using evacuated tube solar collectors ETSC integrated with nano-enhancer phase change material (NE-PCM). To achieve this purpose, a system consisting of 5 linked collecting panels was designed, fabricated, and experimentally investigated. Each panel included a glass-evacuated tube with two concentric aluminum pipes installed inside. NE-PCM was placed between the inlet and outlet air paths inside the evacuated tube to enhance the heat transfer rate. The performance was investigated with and without NE-PCM at five mass flow rates (0.006, 0.008, 0.01, 0.03, and 0.05 kg/s). Experimental results revealed that the highest temperature was 116, 108, 102, 95, and 93 °C, respectively, for the above mass flow rates without adding NE-PCM. The outlet temperature was decreased by 6-15 °C when using NE-PCM. The SAH efficiency was increased by 29.62% compared to the system without NE-PCM at 0.05 kg/s. The maximum thermal efficiency for the system with NE-PCM was 62.66% at 0.05 kg/s, and the pressure drop was 6.79 kPa under the same conditions. As well known, the hot air is used for a variety of purposes including space heating, food processing, drying of fruit, vegetables, dairy, and solar cooking.


Assuntos
Parafina , Energia Solar , Luz Solar , Temperatura , Óxidos
17.
Eur J Obstet Gynecol Reprod Biol ; 284: 105-109, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36966588

RESUMO

OBJECTIVE (S): To compare non-invasive urodynamic findings in women with and without pelvic floor distress and to investigate the patient characteristics affecting maximum flow rates. STUDY DESIGN: This is a retrospective study including data derived from a prospective cohort study evaluating free uroflowmetry findings in asymptomatic and symptomatic women with urinary dysfunction attending the gynecology outpatient clinic for routine annual control, infertility, abnormal uterine bleeding and pelvic floor dysfunction. Data regarding baseline characteristics, questionnaires, urogynecologic examination findings and free uroflowmetry results were retrieved. Women were grouped according to the Turkish validated Pelvic Floor Distress Inventory (PFDI-20); women who scored 0 or 1 points for each item ("no" or "not at all") were considered as asymptomatic in terms of pelvic floor dysfunction, and women who scored 2 or more points to any item were accepted as symptomatic. Baseline characteristics, clinical examination findings and free uroflowmetry data were compared among the groups using Student's-t or Mann-Whitney U tests, Chi-square test or Fisher's exact tests, where appropriate. Correlations and their significance, and patient characteristics affecting Qmax were investigated using the Pearson test. A multiple linear regression model was used to identify independent factors affecting Qmax. RESULTS: The study population (n = 186) comprised asymptomatic (n = 70, 37.6%) and symptomatic (n = 116, 62.4%) women according to the scores of the PFDI-20. Corrected Qmax, TQmax, Tvv and PVR were found significantly lower in asymptomatic women (p ≤ 0.001). In asymptomatic women, PVR was <100 mL in 98.5%, and <50 mL in 80%. In multivariate linear regression analysis parity, obstructive subscale score of the UDI-6, previous mid-urethral sling surgery and hysterectomy were found to affect Qmax negatively, whereas VV was found to affect Qmax positively. CONCLUSION(S): Although significantly different, overlapping wide ranges of non-invasive urodynamic findings have been observed in women with and without pelvic floor distress in the present study population. Maximum urinary flow rates were significantly affected by patient characteristics such as parity, obstructive symptoms, prior incontinence surgery and hysterectomy. There is need for further larger studies considering all possible factors that may affect voiding.


Assuntos
Diafragma da Pelve , Incontinência Urinária , Humanos , Feminino , Masculino , Urodinâmica , Estudos Retrospectivos , Estudos Prospectivos
18.
Pharmaceutics ; 15(8)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631345

RESUMO

In this work, a non-isothermal pore network (PN) model with quasi-steady vapor transport and transient heat transfer is presented for the first time for the application of primary freeze drying. The pore-scale resolved model is physically based and allows for the investigation of correlations between spatially distributed structure and transport conditions. The studied examples were regular PN lattices with a significantly different structure, namely a spatially homogeneous PN, also denoted as monomodal PN, and a PN with significant structure variation, referred to as bimodal PN because of its bimodal pore size distribution. The material properties selected for the solid skeleton in this study are equivalent to those of maltodextrin. The temperature ranges applied here were -28 °C to -18 °C in the PN and -42 °C in the surrounding environment. The environmental vapor pressure was 10 Pa. The PNs were dried with constant temperature boundary conditions, and heat was transferred at the top side by the vapor leaving the PN. It is shown how the structural peculiarities affect the local heat and mass transfer conditions and result in a significant widening of the sublimation front in the case of the bimodal PN. The possibility of spatially and temporally resolved front structures is a unique feature of the PN model and allows the study of situations that are not yet described by classical continuum approaches, namely heterogeneous frozen porous materials. As demonstrated by the thin layers studied here, the pore-scale simulations are of particular interest for such situations, such as in lyomicroscopes or collagen scaffolds, where a length-scale separation between dry and ice-saturated regions is not possible.

19.
Healthcare (Basel) ; 10(3)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35326976

RESUMO

Xerostomia plays a major role in higher interdialytic weight gain (IDWG), which causes cardiovascular complications in patients who undergo hemodialysis. However, few studies have determined a method to manage xerostomia. This study determines the effect of transcutaneous electrical acupoint stimulation (TEAS) on hemodialysis patients with xerostomia and the percentage of IDWG. The study was a single-blind and quasi-experimental study. There are 75 participants: 37 in the TEAS group and 38 in the contrast group. The TEAS group used 250 µs and 50 Hz and the contrast group used 50 µs and 2 Hz three times a week for 3 weeks to stimulate ST 6 and TE17 acupoints. The salivary flow rates, dry mouth, and %IDWG were determined before, during and one week after the program. Compared with the contrast group, the TEAS group showed a significantly improved salivary flow rate (mL/min) (F (2, 123) = 15.28, p < 0.0001), and patients recovered their normal salivary flow rate. However, the results show that both groups showed significant improvement in dry mouth after treatment. The TEAS group demonstrated no effect in terms of %IDWG, as expected. The results show that a TEAS program is an effective means of symptom management for xerostomia patients who undergo hemodialysis. A TEAS program can be used to manage symptoms for xerostomia patients who undergo hemodialysis.

20.
Int J Occup Saf Ergon ; 28(1): 62-67, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34162316

RESUMO

This article presents paraffin oil mist penetration tests of commercially available air-purifying respirators of different construction conducted using the method described by Standard No. ISO 16900-3:2012, which incorporates flow rates (up to 255 l/min) of test aerosol. The testing method reflects differences in work intensity during the use of respirators. Moreover, the experimental stand, designed according to the international specifications, is described. The results show that the higher the paraffin oil mist flow rate, the higher the penetration index, irrespective of the testing method used and the type of respirator investigated. While at high flow rates, filtering half masks of the first protection class (FFP1) met the requirements of their protection class according to European Standard No. EN 149:20001+A1:2009, filtering half masks of the second and the third protection class (FFP2 and FFP3) did not.


Assuntos
Dispositivos de Proteção Respiratória , Aerossóis , Humanos , Óleos , Parafina
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